| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S E M _ C H 3 -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1992-2006, Free Software Foundation, Inc. -- |
| -- -- |
| -- GNAT is free software; you can redistribute it and/or modify it under -- |
| -- terms of the GNU General Public License as published by the Free Soft- -- |
| -- ware Foundation; either version 2, or (at your option) any later ver- -- |
| -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- |
| -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- |
| -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- |
| -- for more details. You should have received a copy of the GNU General -- |
| -- Public License distributed with GNAT; see file COPYING. If not, write -- |
| -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, -- |
| -- Boston, MA 02110-1301, USA. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| with Atree; use Atree; |
| with Checks; use Checks; |
| with Elists; use Elists; |
| with Einfo; use Einfo; |
| with Errout; use Errout; |
| with Eval_Fat; use Eval_Fat; |
| with Exp_Ch3; use Exp_Ch3; |
| with Exp_Dist; use Exp_Dist; |
| with Exp_Tss; use Exp_Tss; |
| with Exp_Util; use Exp_Util; |
| with Freeze; use Freeze; |
| with Itypes; use Itypes; |
| with Layout; use Layout; |
| with Lib; use Lib; |
| with Lib.Xref; use Lib.Xref; |
| with Namet; use Namet; |
| with Nmake; use Nmake; |
| with Opt; use Opt; |
| with Restrict; use Restrict; |
| with Rident; use Rident; |
| with Rtsfind; use Rtsfind; |
| with Sem; use Sem; |
| with Sem_Case; use Sem_Case; |
| with Sem_Cat; use Sem_Cat; |
| with Sem_Ch6; use Sem_Ch6; |
| with Sem_Ch7; use Sem_Ch7; |
| with Sem_Ch8; use Sem_Ch8; |
| with Sem_Ch13; use Sem_Ch13; |
| with Sem_Disp; use Sem_Disp; |
| with Sem_Dist; use Sem_Dist; |
| with Sem_Elim; use Sem_Elim; |
| with Sem_Eval; use Sem_Eval; |
| with Sem_Mech; use Sem_Mech; |
| with Sem_Res; use Sem_Res; |
| with Sem_Smem; use Sem_Smem; |
| with Sem_Type; use Sem_Type; |
| with Sem_Util; use Sem_Util; |
| with Sem_Warn; use Sem_Warn; |
| with Stand; use Stand; |
| with Sinfo; use Sinfo; |
| with Snames; use Snames; |
| with Targparm; use Targparm; |
| with Tbuild; use Tbuild; |
| with Ttypes; use Ttypes; |
| with Uintp; use Uintp; |
| with Urealp; use Urealp; |
| |
| package body Sem_Ch3 is |
| |
| ----------------------- |
| -- Local Subprograms -- |
| ----------------------- |
| |
| procedure Add_Interface_Tag_Components |
| (N : Node_Id; Typ : Entity_Id); |
| -- Ada 2005 (AI-251): Add the tag components corresponding to all the |
| -- abstract interface types implemented by a record type or a derived |
| -- record type. |
| |
| procedure Build_Derived_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id; |
| Is_Completion : Boolean; |
| Derive_Subps : Boolean := True); |
| -- Create and decorate a Derived_Type given the Parent_Type entity. N is |
| -- the N_Full_Type_Declaration node containing the derived type definition. |
| -- Parent_Type is the entity for the parent type in the derived type |
| -- definition and Derived_Type the actual derived type. Is_Completion must |
| -- be set to False if Derived_Type is the N_Defining_Identifier node in N |
| -- (ie Derived_Type = Defining_Identifier (N)). In this case N is not the |
| -- completion of a private type declaration. If Is_Completion is set to |
| -- True, N is the completion of a private type declaration and Derived_Type |
| -- is different from the defining identifier inside N (i.e. Derived_Type /= |
| -- Defining_Identifier (N)). Derive_Subps indicates whether the parent |
| -- subprograms should be derived. The only case where this parameter is |
| -- False is when Build_Derived_Type is recursively called to process an |
| -- implicit derived full type for a type derived from a private type (in |
| -- that case the subprograms must only be derived for the private view of |
| -- the type). |
| |
| -- ??? These flags need a bit of re-examination and re-documentation: |
| -- ??? are they both necessary (both seem related to the recursion)? |
| |
| procedure Build_Derived_Access_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id); |
| -- Subsidiary procedure to Build_Derived_Type. For a derived access type, |
| -- create an implicit base if the parent type is constrained or if the |
| -- subtype indication has a constraint. |
| |
| procedure Build_Derived_Array_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id); |
| -- Subsidiary procedure to Build_Derived_Type. For a derived array type, |
| -- create an implicit base if the parent type is constrained or if the |
| -- subtype indication has a constraint. |
| |
| procedure Build_Derived_Concurrent_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id); |
| -- Subsidiary procedure to Build_Derived_Type. For a derived task or pro- |
| -- tected type, inherit entries and protected subprograms, check legality |
| -- of discriminant constraints if any. |
| |
| procedure Build_Derived_Enumeration_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id); |
| -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration |
| -- type, we must create a new list of literals. Types derived from |
| -- Character and Wide_Character are special-cased. |
| |
| procedure Build_Derived_Numeric_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id); |
| -- Subsidiary procedure to Build_Derived_Type. For numeric types, create |
| -- an anonymous base type, and propagate constraint to subtype if needed. |
| |
| procedure Build_Derived_Private_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id; |
| Is_Completion : Boolean; |
| Derive_Subps : Boolean := True); |
| -- Subsidiary procedure to Build_Derived_Type. This procedure is complex |
| -- because the parent may or may not have a completion, and the derivation |
| -- may itself be a completion. |
| |
| procedure Build_Derived_Record_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id; |
| Derive_Subps : Boolean := True); |
| -- Subsidiary procedure for Build_Derived_Type and |
| -- Analyze_Private_Extension_Declaration used for tagged and untagged |
| -- record types. All parameters are as in Build_Derived_Type except that |
| -- N, in addition to being an N_Full_Type_Declaration node, can also be an |
| -- N_Private_Extension_Declaration node. See the definition of this routine |
| -- for much more info. Derive_Subps indicates whether subprograms should |
| -- be derived from the parent type. The only case where Derive_Subps is |
| -- False is for an implicit derived full type for a type derived from a |
| -- private type (see Build_Derived_Type). |
| |
| procedure Complete_Subprograms_Derivation |
| (Partial_View : Entity_Id; |
| Derived_Type : Entity_Id); |
| -- Ada 2005 (AI-251): Used to complete type derivation of private tagged |
| -- types implementing interfaces. In this case some interface primitives |
| -- may have been overriden with the partial-view and, instead of |
| -- re-calculating them, they are included in the list of primitive |
| -- operations of the full-view. |
| |
| function Inherit_Components |
| (N : Node_Id; |
| Parent_Base : Entity_Id; |
| Derived_Base : Entity_Id; |
| Is_Tagged : Boolean; |
| Inherit_Discr : Boolean; |
| Discs : Elist_Id) return Elist_Id; |
| -- Called from Build_Derived_Record_Type to inherit the components of |
| -- Parent_Base (a base type) into the Derived_Base (the derived base type). |
| -- For more information on derived types and component inheritance please |
| -- consult the comment above the body of Build_Derived_Record_Type. |
| -- |
| -- N is the original derived type declaration |
| -- |
| -- Is_Tagged is set if we are dealing with tagged types |
| -- |
| -- If Inherit_Discr is set, Derived_Base inherits its discriminants |
| -- from Parent_Base, otherwise no discriminants are inherited. |
| -- |
| -- Discs gives the list of constraints that apply to Parent_Base in the |
| -- derived type declaration. If Discs is set to No_Elist, then we have |
| -- the following situation: |
| -- |
| -- type Parent (D1..Dn : ..) is [tagged] record ...; |
| -- type Derived is new Parent [with ...]; |
| -- |
| -- which gets treated as |
| -- |
| -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...]; |
| -- |
| -- For untagged types the returned value is an association list. The list |
| -- starts from the association (Parent_Base => Derived_Base), and then it |
| -- contains a sequence of the associations of the form |
| -- |
| -- (Old_Component => New_Component), |
| -- |
| -- where Old_Component is the Entity_Id of a component in Parent_Base |
| -- and New_Component is the Entity_Id of the corresponding component |
| -- in Derived_Base. For untagged records, this association list is |
| -- needed when copying the record declaration for the derived base. |
| -- In the tagged case the value returned is irrelevant. |
| |
| procedure Build_Discriminal (Discrim : Entity_Id); |
| -- Create the discriminal corresponding to discriminant Discrim, that is |
| -- the parameter corresponding to Discrim to be used in initialization |
| -- procedures for the type where Discrim is a discriminant. Discriminals |
| -- are not used during semantic analysis, and are not fully defined |
| -- entities until expansion. Thus they are not given a scope until |
| -- initialization procedures are built. |
| |
| function Build_Discriminant_Constraints |
| (T : Entity_Id; |
| Def : Node_Id; |
| Derived_Def : Boolean := False) return Elist_Id; |
| -- Validate discriminant constraints, and return the list of the |
| -- constraints in order of discriminant declarations. T is the |
| -- discriminated unconstrained type. Def is the N_Subtype_Indication node |
| -- where the discriminants constraints for T are specified. Derived_Def is |
| -- True if we are building the discriminant constraints in a derived type |
| -- definition of the form "type D (...) is new T (xxx)". In this case T is |
| -- the parent type and Def is the constraint "(xxx)" on T and this routine |
| -- sets the Corresponding_Discriminant field of the discriminants in the |
| -- derived type D to point to the corresponding discriminants in the parent |
| -- type T. |
| |
| procedure Build_Discriminated_Subtype |
| (T : Entity_Id; |
| Def_Id : Entity_Id; |
| Elist : Elist_Id; |
| Related_Nod : Node_Id; |
| For_Access : Boolean := False); |
| -- Subsidiary procedure to Constrain_Discriminated_Type and to |
| -- Process_Incomplete_Dependents. Given |
| -- |
| -- T (a possibly discriminated base type) |
| -- Def_Id (a very partially built subtype for T), |
| -- |
| -- the call completes Def_Id to be the appropriate E_*_Subtype. |
| -- |
| -- The Elist is the list of discriminant constraints if any (it is set to |
| -- No_Elist if T is not a discriminated type, and to an empty list if |
| -- T has discriminants but there are no discriminant constraints). The |
| -- Related_Nod is the same as Decl_Node in Create_Constrained_Components. |
| -- The For_Access says whether or not this subtype is really constraining |
| -- an access type. That is its sole purpose is the designated type of an |
| -- access type -- in which case a Private_Subtype Is_For_Access_Subtype |
| -- is built to avoid freezing T when the access subtype is frozen. |
| |
| function Build_Scalar_Bound |
| (Bound : Node_Id; |
| Par_T : Entity_Id; |
| Der_T : Entity_Id) return Node_Id; |
| -- The bounds of a derived scalar type are conversions of the bounds of |
| -- the parent type. Optimize the representation if the bounds are literals. |
| -- Needs a more complete spec--what are the parameters exactly, and what |
| -- exactly is the returned value, and how is Bound affected??? |
| |
| procedure Build_Underlying_Full_View |
| (N : Node_Id; |
| Typ : Entity_Id; |
| Par : Entity_Id); |
| -- If the completion of a private type is itself derived from a private |
| -- type, or if the full view of a private subtype is itself private, the |
| -- back-end has no way to compute the actual size of this type. We build |
| -- an internal subtype declaration of the proper parent type to convey |
| -- this information. This extra mechanism is needed because a full |
| -- view cannot itself have a full view (it would get clobbered during |
| -- view exchanges). |
| |
| procedure Check_Access_Discriminant_Requires_Limited |
| (D : Node_Id; |
| Loc : Node_Id); |
| -- Check the restriction that the type to which an access discriminant |
| -- belongs must be a concurrent type or a descendant of a type with |
| -- the reserved word 'limited' in its declaration. |
| |
| procedure Check_Delta_Expression (E : Node_Id); |
| -- Check that the expression represented by E is suitable for use |
| -- as a delta expression, i.e. it is of real type and is static. |
| |
| procedure Check_Digits_Expression (E : Node_Id); |
| -- Check that the expression represented by E is suitable for use as |
| -- a digits expression, i.e. it is of integer type, positive and static. |
| |
| procedure Check_Initialization (T : Entity_Id; Exp : Node_Id); |
| -- Validate the initialization of an object declaration. T is the |
| -- required type, and Exp is the initialization expression. |
| |
| procedure Check_Or_Process_Discriminants |
| (N : Node_Id; |
| T : Entity_Id; |
| Prev : Entity_Id := Empty); |
| -- If T is the full declaration of an incomplete or private type, check |
| -- the conformance of the discriminants, otherwise process them. Prev |
| -- is the entity of the partial declaration, if any. |
| |
| procedure Check_Real_Bound (Bound : Node_Id); |
| -- Check given bound for being of real type and static. If not, post an |
| -- appropriate message, and rewrite the bound with the real literal zero. |
| |
| procedure Constant_Redeclaration |
| (Id : Entity_Id; |
| N : Node_Id; |
| T : out Entity_Id); |
| -- Various checks on legality of full declaration of deferred constant. |
| -- Id is the entity for the redeclaration, N is the N_Object_Declaration, |
| -- node. The caller has not yet set any attributes of this entity. |
| |
| procedure Convert_Scalar_Bounds |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id; |
| Loc : Source_Ptr); |
| -- For derived scalar types, convert the bounds in the type definition |
| -- to the derived type, and complete their analysis. Given a constraint |
| -- of the form: |
| -- .. new T range Lo .. Hi; |
| -- Lo and Hi are analyzed and resolved with T'Base, the parent_type. |
| -- The bounds of the derived type (the anonymous base) are copies of |
| -- Lo and Hi. Finally, the bounds of the derived subtype are conversions |
| -- of those bounds to the derived_type, so that their typing is |
| -- consistent. |
| |
| procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id); |
| -- Copies attributes from array base type T2 to array base type T1. |
| -- Copies only attributes that apply to base types, but not subtypes. |
| |
| procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id); |
| -- Copies attributes from array subtype T2 to array subtype T1. Copies |
| -- attributes that apply to both subtypes and base types. |
| |
| procedure Create_Constrained_Components |
| (Subt : Entity_Id; |
| Decl_Node : Node_Id; |
| Typ : Entity_Id; |
| Constraints : Elist_Id); |
| -- Build the list of entities for a constrained discriminated record |
| -- subtype. If a component depends on a discriminant, replace its subtype |
| -- using the discriminant values in the discriminant constraint. |
| -- Subt is the defining identifier for the subtype whose list of |
| -- constrained entities we will create. Decl_Node is the type declaration |
| -- node where we will attach all the itypes created. Typ is the base |
| -- discriminated type for the subtype Subt. Constraints is the list of |
| -- discriminant constraints for Typ. |
| |
| function Constrain_Component_Type |
| (Comp : Entity_Id; |
| Constrained_Typ : Entity_Id; |
| Related_Node : Node_Id; |
| Typ : Entity_Id; |
| Constraints : Elist_Id) return Entity_Id; |
| -- Given a discriminated base type Typ, a list of discriminant constraint |
| -- Constraints for Typ and a component of Typ, with type Compon_Type, |
| -- create and return the type corresponding to Compon_type where all |
| -- discriminant references are replaced with the corresponding |
| -- constraint. If no discriminant references occur in Compon_Typ then |
| -- return it as is. Constrained_Typ is the final constrained subtype to |
| -- which the constrained Compon_Type belongs. Related_Node is the node |
| -- where we will attach all the itypes created. |
| |
| procedure Constrain_Access |
| (Def_Id : in out Entity_Id; |
| S : Node_Id; |
| Related_Nod : Node_Id); |
| -- Apply a list of constraints to an access type. If Def_Id is empty, it is |
| -- an anonymous type created for a subtype indication. In that case it is |
| -- created in the procedure and attached to Related_Nod. |
| |
| procedure Constrain_Array |
| (Def_Id : in out Entity_Id; |
| SI : Node_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id; |
| Suffix : Character); |
| -- Apply a list of index constraints to an unconstrained array type. The |
| -- first parameter is the entity for the resulting subtype. A value of |
| -- Empty for Def_Id indicates that an implicit type must be created, but |
| -- creation is delayed (and must be done by this procedure) because other |
| -- subsidiary implicit types must be created first (which is why Def_Id |
| -- is an in/out parameter). The second parameter is a subtype indication |
| -- node for the constrained array to be created (e.g. something of the |
| -- form string (1 .. 10)). Related_Nod gives the place where this type |
| -- has to be inserted in the tree. The Related_Id and Suffix parameters |
| -- are used to build the associated Implicit type name. |
| |
| procedure Constrain_Concurrent |
| (Def_Id : in out Entity_Id; |
| SI : Node_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id; |
| Suffix : Character); |
| -- Apply list of discriminant constraints to an unconstrained concurrent |
| -- type. |
| -- |
| -- SI is the N_Subtype_Indication node containing the constraint and |
| -- the unconstrained type to constrain. |
| -- |
| -- Def_Id is the entity for the resulting constrained subtype. A value |
| -- of Empty for Def_Id indicates that an implicit type must be created, |
| -- but creation is delayed (and must be done by this procedure) because |
| -- other subsidiary implicit types must be created first (which is why |
| -- Def_Id is an in/out parameter). |
| -- |
| -- Related_Nod gives the place where this type has to be inserted |
| -- in the tree |
| -- |
| -- The last two arguments are used to create its external name if needed. |
| |
| function Constrain_Corresponding_Record |
| (Prot_Subt : Entity_Id; |
| Corr_Rec : Entity_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id) return Entity_Id; |
| -- When constraining a protected type or task type with discriminants, |
| -- constrain the corresponding record with the same discriminant values. |
| |
| procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id); |
| -- Constrain a decimal fixed point type with a digits constraint and/or a |
| -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity. |
| |
| procedure Constrain_Discriminated_Type |
| (Def_Id : Entity_Id; |
| S : Node_Id; |
| Related_Nod : Node_Id; |
| For_Access : Boolean := False); |
| -- Process discriminant constraints of composite type. Verify that values |
| -- have been provided for all discriminants, that the original type is |
| -- unconstrained, and that the types of the supplied expressions match |
| -- the discriminant types. The first three parameters are like in routine |
| -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation |
| -- of For_Access. |
| |
| procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id); |
| -- Constrain an enumeration type with a range constraint. This is identical |
| -- to Constrain_Integer, but for the Ekind of the resulting subtype. |
| |
| procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id); |
| -- Constrain a floating point type with either a digits constraint |
| -- and/or a range constraint, building a E_Floating_Point_Subtype. |
| |
| procedure Constrain_Index |
| (Index : Node_Id; |
| S : Node_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id; |
| Suffix : Character; |
| Suffix_Index : Nat); |
| -- Process an index constraint in a constrained array declaration. The |
| -- constraint can be a subtype name, or a range with or without an |
| -- explicit subtype mark. The index is the corresponding index of the |
| -- unconstrained array. The Related_Id and Suffix parameters are used to |
| -- build the associated Implicit type name. |
| |
| procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id); |
| -- Build subtype of a signed or modular integer type |
| |
| procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id); |
| -- Constrain an ordinary fixed point type with a range constraint, and |
| -- build an E_Ordinary_Fixed_Point_Subtype entity. |
| |
| procedure Copy_And_Swap (Priv, Full : Entity_Id); |
| -- Copy the Priv entity into the entity of its full declaration |
| -- then swap the two entities in such a manner that the former private |
| -- type is now seen as a full type. |
| |
| procedure Decimal_Fixed_Point_Type_Declaration |
| (T : Entity_Id; |
| Def : Node_Id); |
| -- Create a new decimal fixed point type, and apply the constraint to |
| -- obtain a subtype of this new type. |
| |
| procedure Complete_Private_Subtype |
| (Priv : Entity_Id; |
| Full : Entity_Id; |
| Full_Base : Entity_Id; |
| Related_Nod : Node_Id); |
| -- Complete the implicit full view of a private subtype by setting the |
| -- appropriate semantic fields. If the full view of the parent is a record |
| -- type, build constrained components of subtype. |
| |
| procedure Derive_Interface_Subprograms |
| (Derived_Type : Entity_Id); |
| -- Ada 2005 (AI-251): Subsidiary procedure to Build_Derived_Record_Type. |
| -- Traverse the list of implemented interfaces and derive all their |
| -- subprograms. |
| |
| procedure Derived_Standard_Character |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id); |
| -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles |
| -- derivations from types Standard.Character and Standard.Wide_Character. |
| |
| procedure Derived_Type_Declaration |
| (T : Entity_Id; |
| N : Node_Id; |
| Is_Completion : Boolean); |
| -- Process a derived type declaration. This routine will invoke |
| -- Build_Derived_Type to process the actual derived type definition. |
| -- Parameters N and Is_Completion have the same meaning as in |
| -- Build_Derived_Type. T is the N_Defining_Identifier for the entity |
| -- defined in the N_Full_Type_Declaration node N, that is T is the derived |
| -- type. |
| |
| procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id); |
| -- Insert each literal in symbol table, as an overloadable identifier. Each |
| -- enumeration type is mapped into a sequence of integers, and each literal |
| -- is defined as a constant with integer value. If any of the literals are |
| -- character literals, the type is a character type, which means that |
| -- strings are legal aggregates for arrays of components of the type. |
| |
| function Expand_To_Stored_Constraint |
| (Typ : Entity_Id; |
| Constraint : Elist_Id) return Elist_Id; |
| -- Given a Constraint (i.e. a list of expressions) on the discriminants of |
| -- Typ, expand it into a constraint on the stored discriminants and return |
| -- the new list of expressions constraining the stored discriminants. |
| |
| function Find_Type_Of_Object |
| (Obj_Def : Node_Id; |
| Related_Nod : Node_Id) return Entity_Id; |
| -- Get type entity for object referenced by Obj_Def, attaching the |
| -- implicit types generated to Related_Nod |
| |
| procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id); |
| -- Create a new float, and apply the constraint to obtain subtype of it |
| |
| function Has_Range_Constraint (N : Node_Id) return Boolean; |
| -- Given an N_Subtype_Indication node N, return True if a range constraint |
| -- is present, either directly, or as part of a digits or delta constraint. |
| -- In addition, a digits constraint in the decimal case returns True, since |
| -- it establishes a default range if no explicit range is present. |
| |
| function Is_Valid_Constraint_Kind |
| (T_Kind : Type_Kind; |
| Constraint_Kind : Node_Kind) return Boolean; |
| -- Returns True if it is legal to apply the given kind of constraint to the |
| -- given kind of type (index constraint to an array type, for example). |
| |
| procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id); |
| -- Create new modular type. Verify that modulus is in bounds and is |
| -- a power of two (implementation restriction). |
| |
| procedure New_Concatenation_Op (Typ : Entity_Id); |
| -- Create an abbreviated declaration for an operator in order to |
| -- materialize concatenation on array types. |
| |
| procedure Ordinary_Fixed_Point_Type_Declaration |
| (T : Entity_Id; |
| Def : Node_Id); |
| -- Create a new ordinary fixed point type, and apply the constraint to |
| -- obtain subtype of it. |
| |
| procedure Prepare_Private_Subtype_Completion |
| (Id : Entity_Id; |
| Related_Nod : Node_Id); |
| -- Id is a subtype of some private type. Creates the full declaration |
| -- associated with Id whenever possible, i.e. when the full declaration |
| -- of the base type is already known. Records each subtype into |
| -- Private_Dependents of the base type. |
| |
| procedure Process_Incomplete_Dependents |
| (N : Node_Id; |
| Full_T : Entity_Id; |
| Inc_T : Entity_Id); |
| -- Process all entities that depend on an incomplete type. There include |
| -- subtypes, subprogram types that mention the incomplete type in their |
| -- profiles, and subprogram with access parameters that designate the |
| -- incomplete type. |
| |
| -- Inc_T is the defining identifier of an incomplete type declaration, its |
| -- Ekind is E_Incomplete_Type. |
| -- |
| -- N is the corresponding N_Full_Type_Declaration for Inc_T. |
| -- |
| -- Full_T is N's defining identifier. |
| -- |
| -- Subtypes of incomplete types with discriminants are completed when the |
| -- parent type is. This is simpler than private subtypes, because they can |
| -- only appear in the same scope, and there is no need to exchange views. |
| -- Similarly, access_to_subprogram types may have a parameter or a return |
| -- type that is an incomplete type, and that must be replaced with the |
| -- full type. |
| |
| -- If the full type is tagged, subprogram with access parameters that |
| -- designated the incomplete may be primitive operations of the full type, |
| -- and have to be processed accordingly. |
| |
| procedure Process_Real_Range_Specification (Def : Node_Id); |
| -- Given the type definition for a real type, this procedure processes |
| -- and checks the real range specification of this type definition if |
| -- one is present. If errors are found, error messages are posted, and |
| -- the Real_Range_Specification of Def is reset to Empty. |
| |
| procedure Record_Type_Declaration |
| (T : Entity_Id; |
| N : Node_Id; |
| Prev : Entity_Id); |
| -- Process a record type declaration (for both untagged and tagged |
| -- records). Parameters T and N are exactly like in procedure |
| -- Derived_Type_Declaration, except that no flag Is_Completion is needed |
| -- for this routine. If this is the completion of an incomplete type |
| -- declaration, Prev is the entity of the incomplete declaration, used for |
| -- cross-referencing. Otherwise Prev = T. |
| |
| procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id); |
| -- This routine is used to process the actual record type definition |
| -- (both for untagged and tagged records). Def is a record type |
| -- definition node. This procedure analyzes the components in this |
| -- record type definition. Prev_T is the entity for the enclosing record |
| -- type. It is provided so that its Has_Task flag can be set if any of |
| -- the component have Has_Task set. If the declaration is the completion |
| -- of an incomplete type declaration, Prev_T is the original incomplete |
| -- type, whose full view is the record type. |
| |
| procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id); |
| -- Subsidiary to Build_Derived_Record_Type. For untagged records, we |
| -- build a copy of the declaration tree of the parent, and we create |
| -- independently the list of components for the derived type. Semantic |
| -- information uses the component entities, but record representation |
| -- clauses are validated on the declaration tree. This procedure replaces |
| -- discriminants and components in the declaration with those that have |
| -- been created by Inherit_Components. |
| |
| procedure Set_Fixed_Range |
| (E : Entity_Id; |
| Loc : Source_Ptr; |
| Lo : Ureal; |
| Hi : Ureal); |
| -- Build a range node with the given bounds and set it as the Scalar_Range |
| -- of the given fixed-point type entity. Loc is the source location used |
| -- for the constructed range. See body for further details. |
| |
| procedure Set_Scalar_Range_For_Subtype |
| (Def_Id : Entity_Id; |
| R : Node_Id; |
| Subt : Entity_Id); |
| -- This routine is used to set the scalar range field for a subtype given |
| -- Def_Id, the entity for the subtype, and R, the range expression for the |
| -- scalar range. Subt provides the parent subtype to be used to analyze, |
| -- resolve, and check the given range. |
| |
| procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id); |
| -- Create a new signed integer entity, and apply the constraint to obtain |
| -- the required first named subtype of this type. |
| |
| procedure Set_Stored_Constraint_From_Discriminant_Constraint |
| (E : Entity_Id); |
| -- E is some record type. This routine computes E's Stored_Constraint |
| -- from its Discriminant_Constraint. |
| |
| ----------------------- |
| -- Access_Definition -- |
| ----------------------- |
| |
| function Access_Definition |
| (Related_Nod : Node_Id; |
| N : Node_Id) return Entity_Id |
| is |
| Anon_Type : Entity_Id; |
| Desig_Type : Entity_Id; |
| |
| begin |
| if Is_Entry (Current_Scope) |
| and then Is_Task_Type (Etype (Scope (Current_Scope))) |
| then |
| Error_Msg_N ("task entries cannot have access parameters", N); |
| end if; |
| |
| -- Ada 2005: for an object declaration the corresponding anonymous |
| -- type is declared in the current scope. |
| |
| if Nkind (Related_Nod) = N_Object_Declaration then |
| Anon_Type := |
| Create_Itype |
| (E_Anonymous_Access_Type, Related_Nod, |
| Scope_Id => Current_Scope); |
| |
| -- For the anonymous function result case, retrieve the scope of |
| -- the function specification's associated entity rather than using |
| -- the current scope. The current scope will be the function itself |
| -- if the formal part is currently being analyzed, but will be the |
| -- parent scope in the case of a parameterless function, and we |
| -- always want to use the function's parent scope. |
| |
| elsif Nkind (Related_Nod) = N_Function_Specification |
| and then Nkind (Parent (N)) /= N_Parameter_Specification |
| then |
| Anon_Type := |
| Create_Itype |
| (E_Anonymous_Access_Type, Related_Nod, |
| Scope_Id => Scope (Defining_Unit_Name (Related_Nod))); |
| |
| else |
| -- For access formals, access components, and access |
| -- discriminants, the scope is that of the enclosing declaration, |
| |
| Anon_Type := |
| Create_Itype |
| (E_Anonymous_Access_Type, Related_Nod, |
| Scope_Id => Scope (Current_Scope)); |
| end if; |
| |
| if All_Present (N) |
| and then Ada_Version >= Ada_05 |
| then |
| Error_Msg_N ("ALL is not permitted for anonymous access types", N); |
| end if; |
| |
| -- Ada 2005 (AI-254): In case of anonymous access to subprograms |
| -- call the corresponding semantic routine |
| |
| if Present (Access_To_Subprogram_Definition (N)) then |
| Access_Subprogram_Declaration |
| (T_Name => Anon_Type, |
| T_Def => Access_To_Subprogram_Definition (N)); |
| |
| if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then |
| Set_Ekind |
| (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type); |
| else |
| Set_Ekind |
| (Anon_Type, E_Anonymous_Access_Subprogram_Type); |
| end if; |
| |
| return Anon_Type; |
| end if; |
| |
| Find_Type (Subtype_Mark (N)); |
| Desig_Type := Entity (Subtype_Mark (N)); |
| |
| Set_Directly_Designated_Type |
| (Anon_Type, Desig_Type); |
| Set_Etype (Anon_Type, Anon_Type); |
| Init_Size_Align (Anon_Type); |
| Set_Depends_On_Private (Anon_Type, Has_Private_Component (Anon_Type)); |
| |
| -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs |
| -- from Ada 95 semantics. In Ada 2005, anonymous access must specify |
| -- if the null value is allowed. In Ada 95 the null value is never |
| -- allowed. |
| |
| if Ada_Version >= Ada_05 then |
| Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N)); |
| else |
| Set_Can_Never_Be_Null (Anon_Type, True); |
| end if; |
| |
| -- The anonymous access type is as public as the discriminated type or |
| -- subprogram that defines it. It is imported (for back-end purposes) |
| -- if the designated type is. |
| |
| Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type))); |
| |
| -- Ada 2005 (AI-50217): Propagate the attribute that indicates that the |
| -- designated type comes from the limited view (for back-end purposes). |
| |
| Set_From_With_Type (Anon_Type, From_With_Type (Desig_Type)); |
| |
| -- Ada 2005 (AI-231): Propagate the access-constant attribute |
| |
| Set_Is_Access_Constant (Anon_Type, Constant_Present (N)); |
| |
| -- The context is either a subprogram declaration, object declaration, |
| -- or an access discriminant, in a private or a full type declaration. |
| -- In the case of a subprogram, if the designated type is incomplete, |
| -- the operation will be a primitive operation of the full type, to be |
| -- updated subsequently. If the type is imported through a limited_with |
| -- clause, the subprogram is not a primitive operation of the type |
| -- (which is declared elsewhere in some other scope). |
| |
| if Ekind (Desig_Type) = E_Incomplete_Type |
| and then not From_With_Type (Desig_Type) |
| and then Is_Overloadable (Current_Scope) |
| then |
| Append_Elmt (Current_Scope, Private_Dependents (Desig_Type)); |
| Set_Has_Delayed_Freeze (Current_Scope); |
| end if; |
| |
| -- Ada 2005: if the designated type is an interface that may contain |
| -- tasks, create a Master entity for the declaration. This must be done |
| -- before expansion of the full declaration, because the declaration |
| -- may include an expression that is an allocator, whose expansion needs |
| -- the proper Master for the created tasks. |
| |
| if Nkind (Related_Nod) = N_Object_Declaration |
| and then Expander_Active |
| and then Is_Interface (Desig_Type) |
| and then Is_Limited_Record (Desig_Type) |
| then |
| Build_Class_Wide_Master (Anon_Type); |
| end if; |
| |
| return Anon_Type; |
| end Access_Definition; |
| |
| ----------------------------------- |
| -- Access_Subprogram_Declaration -- |
| ----------------------------------- |
| |
| procedure Access_Subprogram_Declaration |
| (T_Name : Entity_Id; |
| T_Def : Node_Id) |
| is |
| Formals : constant List_Id := Parameter_Specifications (T_Def); |
| Formal : Entity_Id; |
| D_Ityp : Node_Id; |
| |
| Desig_Type : constant Entity_Id := |
| Create_Itype (E_Subprogram_Type, Parent (T_Def)); |
| |
| begin |
| -- Associate the Itype node with the inner full-type declaration |
| -- or subprogram spec. This is required to handle nested anonymous |
| -- declarations. For example: |
| |
| -- procedure P |
| -- (X : access procedure |
| -- (Y : access procedure |
| -- (Z : access T))) |
| |
| D_Ityp := Associated_Node_For_Itype (Desig_Type); |
| while Nkind (D_Ityp) /= N_Full_Type_Declaration |
| and then Nkind (D_Ityp) /= N_Procedure_Specification |
| and then Nkind (D_Ityp) /= N_Function_Specification |
| and then Nkind (D_Ityp) /= N_Object_Declaration |
| and then Nkind (D_Ityp) /= N_Object_Renaming_Declaration |
| and then Nkind (D_Ityp) /= N_Formal_Type_Declaration |
| loop |
| D_Ityp := Parent (D_Ityp); |
| pragma Assert (D_Ityp /= Empty); |
| end loop; |
| |
| Set_Associated_Node_For_Itype (Desig_Type, D_Ityp); |
| |
| if Nkind (D_Ityp) = N_Procedure_Specification |
| or else Nkind (D_Ityp) = N_Function_Specification |
| then |
| Set_Scope (Desig_Type, Scope (Defining_Unit_Name (D_Ityp))); |
| |
| elsif Nkind (D_Ityp) = N_Full_Type_Declaration |
| or else Nkind (D_Ityp) = N_Object_Declaration |
| or else Nkind (D_Ityp) = N_Object_Renaming_Declaration |
| or else Nkind (D_Ityp) = N_Formal_Type_Declaration |
| then |
| Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp))); |
| end if; |
| |
| if Nkind (T_Def) = N_Access_Function_Definition then |
| if Nkind (Result_Definition (T_Def)) = N_Access_Definition then |
| Set_Etype |
| (Desig_Type, |
| Access_Definition (T_Def, Result_Definition (T_Def))); |
| else |
| Analyze (Result_Definition (T_Def)); |
| Set_Etype (Desig_Type, Entity (Result_Definition (T_Def))); |
| end if; |
| |
| if not (Is_Type (Etype (Desig_Type))) then |
| Error_Msg_N |
| ("expect type in function specification", |
| Result_Definition (T_Def)); |
| end if; |
| |
| else |
| Set_Etype (Desig_Type, Standard_Void_Type); |
| end if; |
| |
| if Present (Formals) then |
| New_Scope (Desig_Type); |
| Process_Formals (Formals, Parent (T_Def)); |
| |
| -- A bit of a kludge here, End_Scope requires that the parent |
| -- pointer be set to something reasonable, but Itypes don't have |
| -- parent pointers. So we set it and then unset it ??? If and when |
| -- Itypes have proper parent pointers to their declarations, this |
| -- kludge can be removed. |
| |
| Set_Parent (Desig_Type, T_Name); |
| End_Scope; |
| Set_Parent (Desig_Type, Empty); |
| end if; |
| |
| -- The return type and/or any parameter type may be incomplete. Mark |
| -- the subprogram_type as depending on the incomplete type, so that |
| -- it can be updated when the full type declaration is seen. |
| |
| if Present (Formals) then |
| Formal := First_Formal (Desig_Type); |
| while Present (Formal) loop |
| if Ekind (Formal) /= E_In_Parameter |
| and then Nkind (T_Def) = N_Access_Function_Definition |
| then |
| Error_Msg_N ("functions can only have IN parameters", Formal); |
| end if; |
| |
| if Ekind (Etype (Formal)) = E_Incomplete_Type then |
| Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal))); |
| Set_Has_Delayed_Freeze (Desig_Type); |
| end if; |
| |
| Next_Formal (Formal); |
| end loop; |
| end if; |
| |
| if Ekind (Etype (Desig_Type)) = E_Incomplete_Type |
| and then not Has_Delayed_Freeze (Desig_Type) |
| then |
| Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type))); |
| Set_Has_Delayed_Freeze (Desig_Type); |
| end if; |
| |
| Check_Delayed_Subprogram (Desig_Type); |
| |
| if Protected_Present (T_Def) then |
| Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type); |
| Set_Convention (Desig_Type, Convention_Protected); |
| else |
| Set_Ekind (T_Name, E_Access_Subprogram_Type); |
| end if; |
| |
| Set_Etype (T_Name, T_Name); |
| Init_Size_Align (T_Name); |
| Set_Directly_Designated_Type (T_Name, Desig_Type); |
| |
| -- Ada 2005 (AI-231): Propagate the null-excluding attribute |
| |
| Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def)); |
| |
| Check_Restriction (No_Access_Subprograms, T_Def); |
| end Access_Subprogram_Declaration; |
| |
| ---------------------------- |
| -- Access_Type_Declaration -- |
| ---------------------------- |
| |
| procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is |
| S : constant Node_Id := Subtype_Indication (Def); |
| P : constant Node_Id := Parent (Def); |
| |
| Desig : Entity_Id; |
| -- Designated type |
| |
| begin |
| -- Check for permissible use of incomplete type |
| |
| if Nkind (S) /= N_Subtype_Indication then |
| Analyze (S); |
| |
| if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then |
| Set_Directly_Designated_Type (T, Entity (S)); |
| else |
| Set_Directly_Designated_Type (T, |
| Process_Subtype (S, P, T, 'P')); |
| end if; |
| |
| else |
| Set_Directly_Designated_Type (T, |
| Process_Subtype (S, P, T, 'P')); |
| end if; |
| |
| if All_Present (Def) or Constant_Present (Def) then |
| Set_Ekind (T, E_General_Access_Type); |
| else |
| Set_Ekind (T, E_Access_Type); |
| end if; |
| |
| if Base_Type (Designated_Type (T)) = T then |
| Error_Msg_N ("access type cannot designate itself", S); |
| |
| -- In Ada 2005, the type may have a limited view through some unit |
| -- in its own context, allowing the following circularity that cannot |
| -- be detected earlier |
| |
| elsif Is_Class_Wide_Type (Designated_Type (T)) |
| and then Etype (Designated_Type (T)) = T |
| then |
| Error_Msg_N |
| ("access type cannot designate its own classwide type", S); |
| |
| -- Clean up indication of tagged status to prevent cascaded errors |
| |
| Set_Is_Tagged_Type (T, False); |
| end if; |
| |
| Set_Etype (T, T); |
| |
| -- If the type has appeared already in a with_type clause, it is |
| -- frozen and the pointer size is already set. Else, initialize. |
| |
| if not From_With_Type (T) then |
| Init_Size_Align (T); |
| end if; |
| |
| Set_Is_Access_Constant (T, Constant_Present (Def)); |
| |
| Desig := Designated_Type (T); |
| |
| -- If designated type is an imported tagged type, indicate that the |
| -- access type is also imported, and therefore restricted in its use. |
| -- The access type may already be imported, so keep setting otherwise. |
| |
| -- Ada 2005 (AI-50217): If the non-limited view of the designated type |
| -- is available, use it as the designated type of the access type, so |
| -- that the back-end gets a usable entity. |
| |
| declare |
| N_Desig : Entity_Id; |
| |
| begin |
| if From_With_Type (Desig) |
| and then Ekind (Desig) /= E_Access_Type |
| then |
| Set_From_With_Type (T); |
| |
| if Ekind (Desig) = E_Incomplete_Type then |
| N_Desig := Non_Limited_View (Desig); |
| |
| else pragma Assert (Ekind (Desig) = E_Class_Wide_Type); |
| if From_With_Type (Etype (Desig)) then |
| N_Desig := Non_Limited_View (Etype (Desig)); |
| else |
| N_Desig := Etype (Desig); |
| end if; |
| end if; |
| |
| pragma Assert (Present (N_Desig)); |
| Set_Directly_Designated_Type (T, N_Desig); |
| end if; |
| end; |
| |
| -- Note that Has_Task is always false, since the access type itself |
| -- is not a task type. See Einfo for more description on this point. |
| -- Exactly the same consideration applies to Has_Controlled_Component. |
| |
| Set_Has_Task (T, False); |
| Set_Has_Controlled_Component (T, False); |
| |
| -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant |
| -- attributes |
| |
| Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def)); |
| Set_Is_Access_Constant (T, Constant_Present (Def)); |
| end Access_Type_Declaration; |
| |
| ---------------------------------- |
| -- Add_Interface_Tag_Components -- |
| ---------------------------------- |
| |
| procedure Add_Interface_Tag_Components |
| (N : Node_Id; |
| Typ : Entity_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| Elmt : Elmt_Id; |
| Ext : Node_Id; |
| L : List_Id; |
| Last_Tag : Node_Id; |
| Comp : Node_Id; |
| |
| procedure Add_Tag (Iface : Entity_Id); |
| -- Comment required ??? |
| |
| ------------- |
| -- Add_Tag -- |
| ------------- |
| |
| procedure Add_Tag (Iface : Entity_Id) is |
| Decl : Node_Id; |
| Def : Node_Id; |
| Tag : Entity_Id; |
| Offset : Entity_Id; |
| |
| begin |
| pragma Assert (Is_Tagged_Type (Iface) |
| and then Is_Interface (Iface)); |
| |
| Def := |
| Make_Component_Definition (Loc, |
| Aliased_Present => True, |
| Subtype_Indication => |
| New_Occurrence_Of (RTE (RE_Interface_Tag), Loc)); |
| |
| Tag := Make_Defining_Identifier (Loc, New_Internal_Name ('V')); |
| |
| Decl := |
| Make_Component_Declaration (Loc, |
| Defining_Identifier => Tag, |
| Component_Definition => Def); |
| |
| Analyze_Component_Declaration (Decl); |
| |
| Set_Analyzed (Decl); |
| Set_Ekind (Tag, E_Component); |
| Set_Is_Limited_Record (Tag); |
| Set_Is_Tag (Tag); |
| Init_Component_Location (Tag); |
| |
| pragma Assert (Is_Frozen (Iface)); |
| |
| Set_DT_Entry_Count (Tag, |
| DT_Entry_Count (First_Entity (Iface))); |
| |
| if No (Last_Tag) then |
| Prepend (Decl, L); |
| else |
| Insert_After (Last_Tag, Decl); |
| end if; |
| |
| Last_Tag := Decl; |
| |
| -- If the ancestor has discriminants we need to give special support |
| -- to store the offset_to_top value of the secondary dispatch tables. |
| -- For this purpose we add a supplementary component just after the |
| -- field that contains the tag associated with each secondary DT. |
| |
| if Typ /= Etype (Typ) |
| and then Has_Discriminants (Etype (Typ)) |
| then |
| Def := |
| Make_Component_Definition (Loc, |
| Subtype_Indication => |
| New_Occurrence_Of (RTE (RE_Storage_Offset), Loc)); |
| |
| Offset := |
| Make_Defining_Identifier (Loc, New_Internal_Name ('V')); |
| |
| Decl := |
| Make_Component_Declaration (Loc, |
| Defining_Identifier => Offset, |
| Component_Definition => Def); |
| |
| Analyze_Component_Declaration (Decl); |
| |
| Set_Analyzed (Decl); |
| Set_Ekind (Offset, E_Component); |
| Init_Component_Location (Offset); |
| Insert_After (Last_Tag, Decl); |
| Last_Tag := Decl; |
| end if; |
| end Add_Tag; |
| |
| -- Start of processing for Add_Interface_Tag_Components |
| |
| begin |
| if Ekind (Typ) /= E_Record_Type |
| or else No (Abstract_Interfaces (Typ)) |
| or else Is_Empty_Elmt_List (Abstract_Interfaces (Typ)) |
| or else not RTE_Available (RE_Interface_Tag) |
| then |
| return; |
| end if; |
| |
| if Present (Abstract_Interfaces (Typ)) then |
| |
| -- Find the current last tag |
| |
| if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then |
| Ext := Record_Extension_Part (Type_Definition (N)); |
| else |
| pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition); |
| Ext := Type_Definition (N); |
| end if; |
| |
| Last_Tag := Empty; |
| |
| if not (Present (Component_List (Ext))) then |
| Set_Null_Present (Ext, False); |
| L := New_List; |
| Set_Component_List (Ext, |
| Make_Component_List (Loc, |
| Component_Items => L, |
| Null_Present => False)); |
| else |
| if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then |
| L := Component_Items |
| (Component_List |
| (Record_Extension_Part |
| (Type_Definition (N)))); |
| else |
| L := Component_Items |
| (Component_List |
| (Type_Definition (N))); |
| end if; |
| |
| -- Find the last tag component |
| |
| Comp := First (L); |
| while Present (Comp) loop |
| if Is_Tag (Defining_Identifier (Comp)) then |
| Last_Tag := Comp; |
| end if; |
| |
| Next (Comp); |
| end loop; |
| end if; |
| |
| -- At this point L references the list of components and Last_Tag |
| -- references the current last tag (if any). Now we add the tag |
| -- corresponding with all the interfaces that are not implemented |
| -- by the parent. |
| |
| pragma Assert (Present |
| (First_Elmt (Abstract_Interfaces (Typ)))); |
| |
| Elmt := First_Elmt (Abstract_Interfaces (Typ)); |
| while Present (Elmt) loop |
| Add_Tag (Node (Elmt)); |
| Next_Elmt (Elmt); |
| end loop; |
| end if; |
| end Add_Interface_Tag_Components; |
| |
| ----------------------------------- |
| -- Analyze_Component_Declaration -- |
| ----------------------------------- |
| |
| procedure Analyze_Component_Declaration (N : Node_Id) is |
| Id : constant Entity_Id := Defining_Identifier (N); |
| T : Entity_Id; |
| P : Entity_Id; |
| |
| function Contains_POC (Constr : Node_Id) return Boolean; |
| -- Determines whether a constraint uses the discriminant of a record |
| -- type thus becoming a per-object constraint (POC). |
| |
| function Is_Known_Limited (Typ : Entity_Id) return Boolean; |
| -- Check whether enclosing record is limited, to validate declaration |
| -- of components with limited types. |
| -- This seems a wrong description to me??? |
| -- What is Typ? For sure it can return a result without checking |
| -- the enclosing record (enclosing what???) |
| |
| ------------------ |
| -- Contains_POC -- |
| ------------------ |
| |
| function Contains_POC (Constr : Node_Id) return Boolean is |
| begin |
| case Nkind (Constr) is |
| when N_Attribute_Reference => |
| return Attribute_Name (Constr) = Name_Access |
| and |
| Prefix (Constr) = Scope (Entity (Prefix (Constr))); |
| |
| when N_Discriminant_Association => |
| return Denotes_Discriminant (Expression (Constr)); |
| |
| when N_Identifier => |
| return Denotes_Discriminant (Constr); |
| |
| when N_Index_Or_Discriminant_Constraint => |
| declare |
| IDC : Node_Id; |
| |
| begin |
| IDC := First (Constraints (Constr)); |
| while Present (IDC) loop |
| |
| -- One per-object constraint is sufficient |
| |
| if Contains_POC (IDC) then |
| return True; |
| end if; |
| |
| Next (IDC); |
| end loop; |
| |
| return False; |
| end; |
| |
| when N_Range => |
| return Denotes_Discriminant (Low_Bound (Constr)) |
| or else |
| Denotes_Discriminant (High_Bound (Constr)); |
| |
| when N_Range_Constraint => |
| return Denotes_Discriminant (Range_Expression (Constr)); |
| |
| when others => |
| return False; |
| |
| end case; |
| end Contains_POC; |
| |
| ---------------------- |
| -- Is_Known_Limited -- |
| ---------------------- |
| |
| function Is_Known_Limited (Typ : Entity_Id) return Boolean is |
| P : constant Entity_Id := Etype (Typ); |
| R : constant Entity_Id := Root_Type (Typ); |
| |
| begin |
| if Is_Limited_Record (Typ) then |
| return True; |
| |
| -- If the root type is limited (and not a limited interface) |
| -- so is the current type |
| |
| elsif Is_Limited_Record (R) |
| and then |
| (not Is_Interface (R) |
| or else not Is_Limited_Interface (R)) |
| then |
| return True; |
| |
| -- Else the type may have a limited interface progenitor, but a |
| -- limited record parent. |
| |
| elsif R /= P |
| and then Is_Limited_Record (P) |
| then |
| return True; |
| |
| else |
| return False; |
| end if; |
| end Is_Known_Limited; |
| |
| -- Start of processing for Analyze_Component_Declaration |
| |
| begin |
| Generate_Definition (Id); |
| Enter_Name (Id); |
| |
| if Present (Subtype_Indication (Component_Definition (N))) then |
| T := Find_Type_Of_Object |
| (Subtype_Indication (Component_Definition (N)), N); |
| |
| -- Ada 2005 (AI-230): Access Definition case |
| |
| else |
| pragma Assert (Present |
| (Access_Definition (Component_Definition (N)))); |
| |
| T := Access_Definition |
| (Related_Nod => N, |
| N => Access_Definition (Component_Definition (N))); |
| Set_Is_Local_Anonymous_Access (T); |
| |
| -- Ada 2005 (AI-254) |
| |
| if Present (Access_To_Subprogram_Definition |
| (Access_Definition (Component_Definition (N)))) |
| and then Protected_Present (Access_To_Subprogram_Definition |
| (Access_Definition |
| (Component_Definition (N)))) |
| then |
| T := Replace_Anonymous_Access_To_Protected_Subprogram (N, T); |
| end if; |
| end if; |
| |
| -- If the subtype is a constrained subtype of the enclosing record, |
| -- (which must have a partial view) the back-end does not properly |
| -- handle the recursion. Rewrite the component declaration with an |
| -- explicit subtype indication, which is acceptable to Gigi. We can copy |
| -- the tree directly because side effects have already been removed from |
| -- discriminant constraints. |
| |
| if Ekind (T) = E_Access_Subtype |
| and then Is_Entity_Name (Subtype_Indication (Component_Definition (N))) |
| and then Comes_From_Source (T) |
| and then Nkind (Parent (T)) = N_Subtype_Declaration |
| and then Etype (Directly_Designated_Type (T)) = Current_Scope |
| then |
| Rewrite |
| (Subtype_Indication (Component_Definition (N)), |
| New_Copy_Tree (Subtype_Indication (Parent (T)))); |
| T := Find_Type_Of_Object |
| (Subtype_Indication (Component_Definition (N)), N); |
| end if; |
| |
| -- If the component declaration includes a default expression, then we |
| -- check that the component is not of a limited type (RM 3.7(5)), |
| -- and do the special preanalysis of the expression (see section on |
| -- "Handling of Default and Per-Object Expressions" in the spec of |
| -- package Sem). |
| |
| if Present (Expression (N)) then |
| Analyze_Per_Use_Expression (Expression (N), T); |
| Check_Initialization (T, Expression (N)); |
| |
| if Ada_Version >= Ada_05 |
| and then Is_Access_Type (T) |
| and then Ekind (T) = E_Anonymous_Access_Type |
| then |
| -- Check RM 3.9.2(9): "if the expected type for an expression is |
| -- an anonymous access-to-specific tagged type, then the object |
| -- designated by the expression shall not be dynamically tagged |
| -- unless it is a controlling operand in a call on a dispatching |
| -- operation" |
| |
| if Is_Tagged_Type (Directly_Designated_Type (T)) |
| and then |
| Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type |
| and then |
| Ekind (Directly_Designated_Type (Etype (Expression (N)))) = |
| E_Class_Wide_Type |
| then |
| Error_Msg_N |
| ("access to specific tagged type required ('R'M 3.9.2(9))", |
| Expression (N)); |
| end if; |
| |
| -- (Ada 2005: AI-230): Accessibility check for anonymous |
| -- components |
| |
| if Type_Access_Level (Etype (Expression (N))) > |
| Type_Access_Level (T) |
| then |
| Error_Msg_N |
| ("expression has deeper access level than component " & |
| "('R'M 3.10.2 (12.2))", Expression (N)); |
| end if; |
| end if; |
| end if; |
| |
| -- The parent type may be a private view with unknown discriminants, |
| -- and thus unconstrained. Regular components must be constrained. |
| |
| if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then |
| if Is_Class_Wide_Type (T) then |
| Error_Msg_N |
| ("class-wide subtype with unknown discriminants" & |
| " in component declaration", |
| Subtype_Indication (Component_Definition (N))); |
| else |
| Error_Msg_N |
| ("unconstrained subtype in component declaration", |
| Subtype_Indication (Component_Definition (N))); |
| end if; |
| |
| -- Components cannot be abstract, except for the special case of |
| -- the _Parent field (case of extending an abstract tagged type) |
| |
| elsif Is_Abstract (T) and then Chars (Id) /= Name_uParent then |
| Error_Msg_N ("type of a component cannot be abstract", N); |
| end if; |
| |
| Set_Etype (Id, T); |
| Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N))); |
| |
| -- The component declaration may have a per-object constraint, set |
| -- the appropriate flag in the defining identifier of the subtype. |
| |
| if Present (Subtype_Indication (Component_Definition (N))) then |
| declare |
| Sindic : constant Node_Id := |
| Subtype_Indication (Component_Definition (N)); |
| |
| begin |
| if Nkind (Sindic) = N_Subtype_Indication |
| and then Present (Constraint (Sindic)) |
| and then Contains_POC (Constraint (Sindic)) |
| then |
| Set_Has_Per_Object_Constraint (Id); |
| end if; |
| end; |
| end if; |
| |
| -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry |
| -- out some static checks. |
| |
| if Ada_Version >= Ada_05 |
| and then Can_Never_Be_Null (T) |
| then |
| Null_Exclusion_Static_Checks (N); |
| end if; |
| |
| -- If this component is private (or depends on a private type), flag the |
| -- record type to indicate that some operations are not available. |
| |
| P := Private_Component (T); |
| |
| if Present (P) then |
| |
| -- Check for circular definitions |
| |
| if P = Any_Type then |
| Set_Etype (Id, Any_Type); |
| |
| -- There is a gap in the visibility of operations only if the |
| -- component type is not defined in the scope of the record type. |
| |
| elsif Scope (P) = Scope (Current_Scope) then |
| null; |
| |
| elsif Is_Limited_Type (P) then |
| Set_Is_Limited_Composite (Current_Scope); |
| |
| else |
| Set_Is_Private_Composite (Current_Scope); |
| end if; |
| end if; |
| |
| if P /= Any_Type |
| and then Is_Limited_Type (T) |
| and then Chars (Id) /= Name_uParent |
| and then Is_Tagged_Type (Current_Scope) |
| then |
| if Is_Derived_Type (Current_Scope) |
| and then not Is_Known_Limited (Current_Scope) |
| then |
| Error_Msg_N |
| ("extension of nonlimited type cannot have limited components", |
| N); |
| |
| if Is_Interface (Root_Type (Current_Scope)) then |
| Error_Msg_N |
| ("\limitedness is not inherited from limited interface", N); |
| Error_Msg_N |
| ("\add LIMITED to type indication", N); |
| end if; |
| |
| Explain_Limited_Type (T, N); |
| Set_Etype (Id, Any_Type); |
| Set_Is_Limited_Composite (Current_Scope, False); |
| |
| elsif not Is_Derived_Type (Current_Scope) |
| and then not Is_Limited_Record (Current_Scope) |
| and then not Is_Concurrent_Type (Current_Scope) |
| then |
| Error_Msg_N |
| ("nonlimited tagged type cannot have limited components", N); |
| Explain_Limited_Type (T, N); |
| Set_Etype (Id, Any_Type); |
| Set_Is_Limited_Composite (Current_Scope, False); |
| end if; |
| end if; |
| |
| Set_Original_Record_Component (Id, Id); |
| end Analyze_Component_Declaration; |
| |
| -------------------------- |
| -- Analyze_Declarations -- |
| -------------------------- |
| |
| procedure Analyze_Declarations (L : List_Id) is |
| D : Node_Id; |
| Next_Node : Node_Id; |
| Freeze_From : Entity_Id := Empty; |
| |
| procedure Adjust_D; |
| -- Adjust D not to include implicit label declarations, since these |
| -- have strange Sloc values that result in elaboration check problems. |
| -- (They have the sloc of the label as found in the source, and that |
| -- is ahead of the current declarative part). |
| |
| -------------- |
| -- Adjust_D -- |
| -------------- |
| |
| procedure Adjust_D is |
| begin |
| while Present (Prev (D)) |
| and then Nkind (D) = N_Implicit_Label_Declaration |
| loop |
| Prev (D); |
| end loop; |
| end Adjust_D; |
| |
| -- Start of processing for Analyze_Declarations |
| |
| begin |
| D := First (L); |
| while Present (D) loop |
| |
| -- Complete analysis of declaration |
| |
| Analyze (D); |
| Next_Node := Next (D); |
| |
| if No (Freeze_From) then |
| Freeze_From := First_Entity (Current_Scope); |
| end if; |
| |
| -- At the end of a declarative part, freeze remaining entities |
| -- declared in it. The end of the visible declarations of package |
| -- specification is not the end of a declarative part if private |
| -- declarations are present. The end of a package declaration is a |
| -- freezing point only if it a library package. A task definition or |
| -- protected type definition is not a freeze point either. Finally, |
| -- we do not freeze entities in generic scopes, because there is no |
| -- code generated for them and freeze nodes will be generated for |
| -- the instance. |
| |
| -- The end of a package instantiation is not a freeze point, but |
| -- for now we make it one, because the generic body is inserted |
| -- (currently) immediately after. Generic instantiations will not |
| -- be a freeze point once delayed freezing of bodies is implemented. |
| -- (This is needed in any case for early instantiations ???). |
| |
| if No (Next_Node) then |
| if Nkind (Parent (L)) = N_Component_List |
| or else Nkind (Parent (L)) = N_Task_Definition |
| or else Nkind (Parent (L)) = N_Protected_Definition |
| then |
| null; |
| |
| elsif Nkind (Parent (L)) /= N_Package_Specification then |
| if Nkind (Parent (L)) = N_Package_Body then |
| Freeze_From := First_Entity (Current_Scope); |
| end if; |
| |
| Adjust_D; |
| Freeze_All (Freeze_From, D); |
| Freeze_From := Last_Entity (Current_Scope); |
| |
| elsif Scope (Current_Scope) /= Standard_Standard |
| and then not Is_Child_Unit (Current_Scope) |
| and then No (Generic_Parent (Parent (L))) |
| then |
| null; |
| |
| elsif L /= Visible_Declarations (Parent (L)) |
| or else No (Private_Declarations (Parent (L))) |
| or else Is_Empty_List (Private_Declarations (Parent (L))) |
| then |
| Adjust_D; |
| Freeze_All (Freeze_From, D); |
| Freeze_From := Last_Entity (Current_Scope); |
| end if; |
| |
| -- If next node is a body then freeze all types before the body. |
| -- An exception occurs for expander generated bodies, which can |
| -- be recognized by their already being analyzed. The expander |
| -- ensures that all types needed by these bodies have been frozen |
| -- but it is not necessary to freeze all types (and would be wrong |
| -- since it would not correspond to an RM defined freeze point). |
| |
| elsif not Analyzed (Next_Node) |
| and then (Nkind (Next_Node) = N_Subprogram_Body |
| or else Nkind (Next_Node) = N_Entry_Body |
| or else Nkind (Next_Node) = N_Package_Body |
| or else Nkind (Next_Node) = N_Protected_Body |
| or else Nkind (Next_Node) = N_Task_Body |
| or else Nkind (Next_Node) in N_Body_Stub) |
| then |
| Adjust_D; |
| Freeze_All (Freeze_From, D); |
| Freeze_From := Last_Entity (Current_Scope); |
| end if; |
| |
| D := Next_Node; |
| end loop; |
| end Analyze_Declarations; |
| |
| ---------------------------------- |
| -- Analyze_Incomplete_Type_Decl -- |
| ---------------------------------- |
| |
| procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is |
| F : constant Boolean := Is_Pure (Current_Scope); |
| T : Entity_Id; |
| |
| begin |
| Generate_Definition (Defining_Identifier (N)); |
| |
| -- Process an incomplete declaration. The identifier must not have been |
| -- declared already in the scope. However, an incomplete declaration may |
| -- appear in the private part of a package, for a private type that has |
| -- already been declared. |
| |
| -- In this case, the discriminants (if any) must match |
| |
| T := Find_Type_Name (N); |
| |
| Set_Ekind (T, E_Incomplete_Type); |
| Init_Size_Align (T); |
| Set_Is_First_Subtype (T, True); |
| Set_Etype (T, T); |
| |
| -- Ada 2005 (AI-326): Minimum decoration to give support to tagged |
| -- incomplete types. |
| |
| if Tagged_Present (N) then |
| Set_Is_Tagged_Type (T); |
| Make_Class_Wide_Type (T); |
| Set_Primitive_Operations (T, New_Elmt_List); |
| end if; |
| |
| New_Scope (T); |
| |
| Set_Stored_Constraint (T, No_Elist); |
| |
| if Present (Discriminant_Specifications (N)) then |
| Process_Discriminants (N); |
| end if; |
| |
| End_Scope; |
| |
| -- If the type has discriminants, non-trivial subtypes may be be |
| -- declared before the full view of the type. The full views of those |
| -- subtypes will be built after the full view of the type. |
| |
| Set_Private_Dependents (T, New_Elmt_List); |
| Set_Is_Pure (T, F); |
| end Analyze_Incomplete_Type_Decl; |
| |
| ----------------------------------- |
| -- Analyze_Interface_Declaration -- |
| ----------------------------------- |
| |
| procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is |
| begin |
| Set_Is_Tagged_Type (T); |
| |
| Set_Is_Limited_Record (T, Limited_Present (Def) |
| or else Task_Present (Def) |
| or else Protected_Present (Def) |
| or else Synchronized_Present (Def)); |
| |
| -- Type is abstract if full declaration carries keyword, or if |
| -- previous partial view did. |
| |
| Set_Is_Abstract (T); |
| Set_Is_Interface (T); |
| |
| Set_Is_Limited_Interface (T, Limited_Present (Def)); |
| Set_Is_Protected_Interface (T, Protected_Present (Def)); |
| Set_Is_Synchronized_Interface (T, Synchronized_Present (Def)); |
| Set_Is_Task_Interface (T, Task_Present (Def)); |
| Set_Abstract_Interfaces (T, New_Elmt_List); |
| Set_Primitive_Operations (T, New_Elmt_List); |
| end Analyze_Interface_Declaration; |
| |
| ----------------------------- |
| -- Analyze_Itype_Reference -- |
| ----------------------------- |
| |
| -- Nothing to do. This node is placed in the tree only for the benefit of |
| -- back end processing, and has no effect on the semantic processing. |
| |
| procedure Analyze_Itype_Reference (N : Node_Id) is |
| begin |
| pragma Assert (Is_Itype (Itype (N))); |
| null; |
| end Analyze_Itype_Reference; |
| |
| -------------------------------- |
| -- Analyze_Number_Declaration -- |
| -------------------------------- |
| |
| procedure Analyze_Number_Declaration (N : Node_Id) is |
| Id : constant Entity_Id := Defining_Identifier (N); |
| E : constant Node_Id := Expression (N); |
| T : Entity_Id; |
| Index : Interp_Index; |
| It : Interp; |
| |
| begin |
| Generate_Definition (Id); |
| Enter_Name (Id); |
| |
| -- This is an optimization of a common case of an integer literal |
| |
| if Nkind (E) = N_Integer_Literal then |
| Set_Is_Static_Expression (E, True); |
| Set_Etype (E, Universal_Integer); |
| |
| Set_Etype (Id, Universal_Integer); |
| Set_Ekind (Id, E_Named_Integer); |
| Set_Is_Frozen (Id, True); |
| return; |
| end if; |
| |
| Set_Is_Pure (Id, Is_Pure (Current_Scope)); |
| |
| -- Process expression, replacing error by integer zero, to avoid |
| -- cascaded errors or aborts further along in the processing |
| |
| -- Replace Error by integer zero, which seems least likely to |
| -- cause cascaded errors. |
| |
| if E = Error then |
| Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0)); |
| Set_Error_Posted (E); |
| end if; |
| |
| Analyze (E); |
| |
| -- Verify that the expression is static and numeric. If |
| -- the expression is overloaded, we apply the preference |
| -- rule that favors root numeric types. |
| |
| if not Is_Overloaded (E) then |
| T := Etype (E); |
| |
| else |
| T := Any_Type; |
| |
| Get_First_Interp (E, Index, It); |
| while Present (It.Typ) loop |
| if (Is_Integer_Type (It.Typ) |
| or else Is_Real_Type (It.Typ)) |
| and then (Scope (Base_Type (It.Typ))) = Standard_Standard |
| then |
| if T = Any_Type then |
| T := It.Typ; |
| |
| elsif It.Typ = Universal_Real |
| or else It.Typ = Universal_Integer |
| then |
| -- Choose universal interpretation over any other |
| |
| T := It.Typ; |
| exit; |
| end if; |
| end if; |
| |
| Get_Next_Interp (Index, It); |
| end loop; |
| end if; |
| |
| if Is_Integer_Type (T) then |
| Resolve (E, T); |
| Set_Etype (Id, Universal_Integer); |
| Set_Ekind (Id, E_Named_Integer); |
| |
| elsif Is_Real_Type (T) then |
| |
| -- Because the real value is converted to universal_real, this is a |
| -- legal context for a universal fixed expression. |
| |
| if T = Universal_Fixed then |
| declare |
| Loc : constant Source_Ptr := Sloc (N); |
| Conv : constant Node_Id := Make_Type_Conversion (Loc, |
| Subtype_Mark => |
| New_Occurrence_Of (Universal_Real, Loc), |
| Expression => Relocate_Node (E)); |
| |
| begin |
| Rewrite (E, Conv); |
| Analyze (E); |
| end; |
| |
| elsif T = Any_Fixed then |
| Error_Msg_N ("illegal context for mixed mode operation", E); |
| |
| -- Expression is of the form : universal_fixed * integer. Try to |
| -- resolve as universal_real. |
| |
| T := Universal_Real; |
| Set_Etype (E, T); |
| end if; |
| |
| Resolve (E, T); |
| Set_Etype (Id, Universal_Real); |
| Set_Ekind (Id, E_Named_Real); |
| |
| else |
| Wrong_Type (E, Any_Numeric); |
| Resolve (E, T); |
| |
| Set_Etype (Id, T); |
| Set_Ekind (Id, E_Constant); |
| Set_Never_Set_In_Source (Id, True); |
| Set_Is_True_Constant (Id, True); |
| return; |
| end if; |
| |
| if Nkind (E) = N_Integer_Literal |
| or else Nkind (E) = N_Real_Literal |
| then |
| Set_Etype (E, Etype (Id)); |
| end if; |
| |
| if not Is_OK_Static_Expression (E) then |
| Flag_Non_Static_Expr |
| ("non-static expression used in number declaration!", E); |
| Rewrite (E, Make_Integer_Literal (Sloc (N), 1)); |
| Set_Etype (E, Any_Type); |
| end if; |
| end Analyze_Number_Declaration; |
| |
| -------------------------------- |
| -- Analyze_Object_Declaration -- |
| -------------------------------- |
| |
| procedure Analyze_Object_Declaration (N : Node_Id) is |
| Loc : constant Source_Ptr := Sloc (N); |
| Id : constant Entity_Id := Defining_Identifier (N); |
| T : Entity_Id; |
| Act_T : Entity_Id; |
| |
| E : Node_Id := Expression (N); |
| -- E is set to Expression (N) throughout this routine. When |
| -- Expression (N) is modified, E is changed accordingly. |
| |
| Prev_Entity : Entity_Id := Empty; |
| |
| function Build_Default_Subtype return Entity_Id; |
| -- If the object is limited or aliased, and if the type is unconstrained |
| -- and there is no expression, the discriminants cannot be modified and |
| -- the subtype of the object is constrained by the defaults, so it is |
| -- worthwhile building the corresponding subtype. |
| |
| function Count_Tasks (T : Entity_Id) return Uint; |
| -- This function is called when a library level object of type is |
| -- declared. It's function is to count the static number of tasks |
| -- declared within the type (it is only called if Has_Tasks is set for |
| -- T). As a side effect, if an array of tasks with non-static bounds or |
| -- a variant record type is encountered, Check_Restrictions is called |
| -- indicating the count is unknown. |
| |
| --------------------------- |
| -- Build_Default_Subtype -- |
| --------------------------- |
| |
| function Build_Default_Subtype return Entity_Id is |
| Constraints : constant List_Id := New_List; |
| Act : Entity_Id; |
| Decl : Node_Id; |
| Disc : Entity_Id; |
| |
| begin |
| Disc := First_Discriminant (T); |
| |
| if No (Discriminant_Default_Value (Disc)) then |
| return T; -- previous error. |
| end if; |
| |
| Act := Make_Defining_Identifier (Loc, New_Internal_Name ('S')); |
| while Present (Disc) loop |
| Append ( |
| New_Copy_Tree ( |
| Discriminant_Default_Value (Disc)), Constraints); |
| Next_Discriminant (Disc); |
| end loop; |
| |
| Decl := |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Act, |
| Subtype_Indication => |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Occurrence_Of (T, Loc), |
| Constraint => |
| Make_Index_Or_Discriminant_Constraint |
| (Loc, Constraints))); |
| |
| Insert_Before (N, Decl); |
| Analyze (Decl); |
| return Act; |
| end Build_Default_Subtype; |
| |
| ----------------- |
| -- Count_Tasks -- |
| ----------------- |
| |
| function Count_Tasks (T : Entity_Id) return Uint is |
| C : Entity_Id; |
| X : Node_Id; |
| V : Uint; |
| |
| begin |
| if Is_Task_Type (T) then |
| return Uint_1; |
| |
| elsif Is_Record_Type (T) then |
| if Has_Discriminants (T) then |
| Check_Restriction (Max_Tasks, N); |
| return Uint_0; |
| |
| else |
| V := Uint_0; |
| C := First_Component (T); |
| while Present (C) loop |
| V := V + Count_Tasks (Etype (C)); |
| Next_Component (C); |
| end loop; |
| |
| return V; |
| end if; |
| |
| elsif Is_Array_Type (T) then |
| X := First_Index (T); |
| V := Count_Tasks (Component_Type (T)); |
| while Present (X) loop |
| C := Etype (X); |
| |
| if not Is_Static_Subtype (C) then |
| Check_Restriction (Max_Tasks, N); |
| return Uint_0; |
| else |
| V := V * (UI_Max (Uint_0, |
| Expr_Value (Type_High_Bound (C)) - |
| Expr_Value (Type_Low_Bound (C)) + Uint_1)); |
| end if; |
| |
| Next_Index (X); |
| end loop; |
| |
| return V; |
| |
| else |
| return Uint_0; |
| end if; |
| end Count_Tasks; |
| |
| -- Start of processing for Analyze_Object_Declaration |
| |
| begin |
| -- There are three kinds of implicit types generated by an |
| -- object declaration: |
| |
| -- 1. Those for generated by the original Object Definition |
| |
| -- 2. Those generated by the Expression |
| |
| -- 3. Those used to constrained the Object Definition with the |
| -- expression constraints when it is unconstrained |
| |
| -- They must be generated in this order to avoid order of elaboration |
| -- issues. Thus the first step (after entering the name) is to analyze |
| -- the object definition. |
| |
| if Constant_Present (N) then |
| Prev_Entity := Current_Entity_In_Scope (Id); |
| |
| -- If homograph is an implicit subprogram, it is overridden by the |
| -- current declaration. |
| |
| if Present (Prev_Entity) |
| and then Is_Overloadable (Prev_Entity) |
| and then Is_Inherited_Operation (Prev_Entity) |
| then |
| Prev_Entity := Empty; |
| end if; |
| end if; |
| |
| if Present (Prev_Entity) then |
| Constant_Redeclaration (Id, N, T); |
| |
| Generate_Reference (Prev_Entity, Id, 'c'); |
| Set_Completion_Referenced (Id); |
| |
| if Error_Posted (N) then |
| |
| -- Type mismatch or illegal redeclaration, Do not analyze |
| -- expression to avoid cascaded errors. |
| |
| T := Find_Type_Of_Object (Object_Definition (N), N); |
| Set_Etype (Id, T); |
| Set_Ekind (Id, E_Variable); |
| return; |
| end if; |
| |
| -- In the normal case, enter identifier at the start to catch premature |
| -- usage in the initialization expression. |
| |
| else |
| Generate_Definition (Id); |
| Enter_Name (Id); |
| |
| T := Find_Type_Of_Object (Object_Definition (N), N); |
| |
| if Error_Posted (Id) then |
| Set_Etype (Id, T); |
| Set_Ekind (Id, E_Variable); |
| return; |
| end if; |
| end if; |
| |
| -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry |
| -- out some static checks |
| |
| if Ada_Version >= Ada_05 |
| and then Can_Never_Be_Null (T) |
| then |
| -- In case of aggregates we must also take care of the correct |
| -- initialization of nested aggregates bug this is done at the |
| -- point of the analysis of the aggregate (see sem_aggr.adb) |
| |
| if Present (Expression (N)) |
| and then Nkind (Expression (N)) = N_Aggregate |
| then |
| null; |
| |
| else |
| declare |
| Save_Typ : constant Entity_Id := Etype (Id); |
| begin |
| Set_Etype (Id, T); -- Temp. decoration for static checks |
| Null_Exclusion_Static_Checks (N); |
| Set_Etype (Id, Save_Typ); |
| end; |
| end if; |
| end if; |
| |
| Set_Is_Pure (Id, Is_Pure (Current_Scope)); |
| |
| -- If deferred constant, make sure context is appropriate. We detect |
| -- a deferred constant as a constant declaration with no expression. |
| -- A deferred constant can appear in a package body if its completion |
| -- is by means of an interface pragma. |
| |
| if Constant_Present (N) |
| and then No (E) |
| then |
| if not Is_Package_Or_Generic_Package (Current_Scope) then |
| Error_Msg_N |
| ("invalid context for deferred constant declaration ('R'M 7.4)", |
| N); |
| Error_Msg_N |
| ("\declaration requires an initialization expression", |
| N); |
| Set_Constant_Present (N, False); |
| |
| -- In Ada 83, deferred constant must be of private type |
| |
| elsif not Is_Private_Type (T) then |
| if Ada_Version = Ada_83 and then Comes_From_Source (N) then |
| Error_Msg_N |
| ("(Ada 83) deferred constant must be private type", N); |
| end if; |
| end if; |
| |
| -- If not a deferred constant, then object declaration freezes its type |
| |
| else |
| Check_Fully_Declared (T, N); |
| Freeze_Before (N, T); |
| end if; |
| |
| -- If the object was created by a constrained array definition, then |
| -- set the link in both the anonymous base type and anonymous subtype |
| -- that are built to represent the array type to point to the object. |
| |
| if Nkind (Object_Definition (Declaration_Node (Id))) = |
| N_Constrained_Array_Definition |
| then |
| Set_Related_Array_Object (T, Id); |
| Set_Related_Array_Object (Base_Type (T), Id); |
| end if; |
| |
| -- Special checks for protected objects not at library level |
| |
| if Is_Protected_Type (T) |
| and then not Is_Library_Level_Entity (Id) |
| then |
| Check_Restriction (No_Local_Protected_Objects, Id); |
| |
| -- Protected objects with interrupt handlers must be at library level |
| |
| -- Ada 2005: this test is not needed (and the corresponding clause |
| -- in the RM is removed) because accessibility checks are sufficient |
| -- to make handlers not at the library level illegal. |
| |
| if Has_Interrupt_Handler (T) |
| and then Ada_Version < Ada_05 |
| then |
| Error_Msg_N |
| ("interrupt object can only be declared at library level", Id); |
| end if; |
| end if; |
| |
| -- The actual subtype of the object is the nominal subtype, unless |
| -- the nominal one is unconstrained and obtained from the expression. |
| |
| Act_T := T; |
| |
| -- Process initialization expression if present and not in error |
| |
| if Present (E) and then E /= Error then |
| Analyze (E); |
| |
| -- In case of errors detected in the analysis of the expression, |
| -- decorate it with the expected type to avoid cascade errors |
| |
| if No (Etype (E)) then |
| Set_Etype (E, T); |
| end if; |
| |
| -- If an initialization expression is present, then we set the |
| -- Is_True_Constant flag. It will be reset if this is a variable |
| -- and it is indeed modified. |
| |
| Set_Is_True_Constant (Id, True); |
| |
| -- If we are analyzing a constant declaration, set its completion |
| -- flag after analyzing the expression. |
| |
| if Constant_Present (N) then |
| Set_Has_Completion (Id); |
| end if; |
| |
| if not Assignment_OK (N) then |
| Check_Initialization (T, E); |
| end if; |
| |
| Set_Etype (Id, T); -- may be overridden later on |
| Resolve (E, T); |
| Check_Unset_Reference (E); |
| |
| if Compile_Time_Known_Value (E) then |
| Set_Current_Value (Id, E); |
| end if; |
| |
| -- Check incorrect use of dynamically tagged expressions. Note |
| -- the use of Is_Tagged_Type (T) which seems redundant but is in |
| -- fact important to avoid spurious errors due to expanded code |
| -- for dispatching functions over an anonymous access type |
| |
| if (Is_Class_Wide_Type (Etype (E)) or else Is_Dynamically_Tagged (E)) |
| and then Is_Tagged_Type (T) |
| and then not Is_Class_Wide_Type (T) |
| then |
| Error_Msg_N ("dynamically tagged expression not allowed!", E); |
| end if; |
| |
| Apply_Scalar_Range_Check (E, T); |
| Apply_Static_Length_Check (E, T); |
| end if; |
| |
| -- If the No_Streams restriction is set, check that the type of the |
| -- object is not, and does not contain, any subtype derived from |
| -- Ada.Streams.Root_Stream_Type. Note that we guard the call to |
| -- Has_Stream just for efficiency reasons. There is no point in |
| -- spending time on a Has_Stream check if the restriction is not set. |
| |
| if Restrictions.Set (No_Streams) then |
| if Has_Stream (T) then |
| Check_Restriction (No_Streams, N); |
| end if; |
| end if; |
| |
| -- Abstract type is never permitted for a variable or constant. |
| -- Note: we inhibit this check for objects that do not come from |
| -- source because there is at least one case (the expansion of |
| -- x'class'input where x is abstract) where we legitimately |
| -- generate an abstract object. |
| |
| if Is_Abstract (T) and then Comes_From_Source (N) then |
| Error_Msg_N ("type of object cannot be abstract", |
| Object_Definition (N)); |
| |
| if Is_CPP_Class (T) then |
| Error_Msg_NE ("\} may need a cpp_constructor", |
| Object_Definition (N), T); |
| end if; |
| |
| -- Case of unconstrained type |
| |
| elsif Is_Indefinite_Subtype (T) then |
| |
| -- Nothing to do in deferred constant case |
| |
| if Constant_Present (N) and then No (E) then |
| null; |
| |
| -- Case of no initialization present |
| |
| elsif No (E) then |
| if No_Initialization (N) then |
| null; |
| |
| elsif Is_Class_Wide_Type (T) then |
| Error_Msg_N |
| ("initialization required in class-wide declaration ", N); |
| |
| else |
| Error_Msg_N |
| ("unconstrained subtype not allowed (need initialization)", |
| Object_Definition (N)); |
| end if; |
| |
| -- Case of initialization present but in error. Set initial |
| -- expression as absent (but do not make above complaints) |
| |
| elsif E = Error then |
| Set_Expression (N, Empty); |
| E := Empty; |
| |
| -- Case of initialization present |
| |
| else |
| -- Not allowed in Ada 83 |
| |
| if not Constant_Present (N) then |
| if Ada_Version = Ada_83 |
| and then Comes_From_Source (Object_Definition (N)) |
| then |
| Error_Msg_N |
| ("(Ada 83) unconstrained variable not allowed", |
| Object_Definition (N)); |
| end if; |
| end if; |
| |
| -- Now we constrain the variable from the initializing expression |
| |
| -- If the expression is an aggregate, it has been expanded into |
| -- individual assignments. Retrieve the actual type from the |
| -- expanded construct. |
| |
| if Is_Array_Type (T) |
| and then No_Initialization (N) |
| and then Nkind (Original_Node (E)) = N_Aggregate |
| then |
| Act_T := Etype (E); |
| |
| else |
| Expand_Subtype_From_Expr (N, T, Object_Definition (N), E); |
| Act_T := Find_Type_Of_Object (Object_Definition (N), N); |
| end if; |
| |
| Set_Is_Constr_Subt_For_U_Nominal (Act_T); |
| |
| if Aliased_Present (N) then |
| Set_Is_Constr_Subt_For_UN_Aliased (Act_T); |
| end if; |
| |
| Freeze_Before (N, Act_T); |
| Freeze_Before (N, T); |
| end if; |
| |
| elsif Is_Array_Type (T) |
| and then No_Initialization (N) |
| and then Nkind (Original_Node (E)) = N_Aggregate |
| then |
| if not Is_Entity_Name (Object_Definition (N)) then |
| Act_T := Etype (E); |
| Check_Compile_Time_Size (Act_T); |
| |
| if Aliased_Present (N) then |
| Set_Is_Constr_Subt_For_UN_Aliased (Act_T); |
| end if; |
| end if; |
| |
| -- When the given object definition and the aggregate are specified |
| -- independently, and their lengths might differ do a length check. |
| -- This cannot happen if the aggregate is of the form (others =>...) |
| |
| if not Is_Constrained (T) then |
| null; |
| |
| elsif Nkind (E) = N_Raise_Constraint_Error then |
| |
| -- Aggregate is statically illegal. Place back in declaration |
| |
| Set_Expression (N, E); |
| Set_No_Initialization (N, False); |
| |
| elsif T = Etype (E) then |
| null; |
| |
| elsif Nkind (E) = N_Aggregate |
| and then Present (Component_Associations (E)) |
| and then Present (Choices (First (Component_Associations (E)))) |
| and then Nkind (First |
| (Choices (First (Component_Associations (E))))) = N_Others_Choice |
| then |
| null; |
| |
| else |
| Apply_Length_Check (E, T); |
| end if; |
| |
| elsif (Is_Limited_Record (T) |
| or else Is_Concurrent_Type (T)) |
| and then not Is_Constrained (T) |
| and then Has_Discriminants (T) |
| then |
| if No (E) then |
| Act_T := Build_Default_Subtype; |
| else |
| -- Ada 2005: a limited object may be initialized by means of an |
| -- aggregate. If the type has default discriminants it has an |
| -- unconstrained nominal type, Its actual subtype will be obtained |
| -- from the aggregate, and not from the default discriminants. |
| |
| Act_T := Etype (E); |
| end if; |
| |
| Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc)); |
| |
| elsif Present (Underlying_Type (T)) |
| and then not Is_Constrained (Underlying_Type (T)) |
| and then Has_Discriminants (Underlying_Type (T)) |
| and then Nkind (E) = N_Function_Call |
| and then Constant_Present (N) |
| then |
| -- The back-end has problems with constants of a discriminated type |
| -- with defaults, if the initial value is a function call. We |
| -- generate an intermediate temporary for the result of the call. |
| -- It is unclear why this should make it acceptable to gcc. ??? |
| |
| Remove_Side_Effects (E); |
| end if; |
| |
| if T = Standard_Wide_Character or else T = Standard_Wide_Wide_Character |
| or else Root_Type (T) = Standard_Wide_String |
| or else Root_Type (T) = Standard_Wide_Wide_String |
| then |
| Check_Restriction (No_Wide_Characters, Object_Definition (N)); |
| end if; |
| |
| -- Now establish the proper kind and type of the object |
| |
| if Constant_Present (N) then |
| Set_Ekind (Id, E_Constant); |
| Set_Never_Set_In_Source (Id, True); |
| Set_Is_True_Constant (Id, True); |
| |
| else |
| Set_Ekind (Id, E_Variable); |
| |
| -- A variable is set as shared passive if it appears in a shared |
| -- passive package, and is at the outer level. This is not done |
| -- for entities generated during expansion, because those are |
| -- always manipulated locally. |
| |
| if Is_Shared_Passive (Current_Scope) |
| and then Is_Library_Level_Entity (Id) |
| and then Comes_From_Source (Id) |
| then |
| Set_Is_Shared_Passive (Id); |
| Check_Shared_Var (Id, T, N); |
| end if; |
| |
| -- Case of no initializing expression present. If the type is not |
| -- fully initialized, then we set Never_Set_In_Source, since this |
| -- is a case of a potentially uninitialized object. Note that we |
| -- do not consider access variables to be fully initialized for |
| -- this purpose, since it still seems dubious if someone declares |
| |
| -- Note that we only do this for source declarations. If the object |
| -- is declared by a generated declaration, we assume that it is not |
| -- appropriate to generate warnings in that case. |
| |
| if No (E) then |
| if (Is_Access_Type (T) |
| or else not Is_Fully_Initialized_Type (T)) |
| and then Comes_From_Source (N) |
| then |
| Set_Never_Set_In_Source (Id); |
| end if; |
| end if; |
| end if; |
| |
| Init_Alignment (Id); |
| Init_Esize (Id); |
| |
| if Aliased_Present (N) then |
| Set_Is_Aliased (Id); |
| |
| if No (E) |
| and then Is_Record_Type (T) |
| and then not Is_Constrained (T) |
| and then Has_Discriminants (T) |
| then |
| Set_Actual_Subtype (Id, Build_Default_Subtype); |
| end if; |
| end if; |
| |
| Set_Etype (Id, Act_T); |
| |
| if Has_Controlled_Component (Etype (Id)) |
| or else Is_Controlled (Etype (Id)) |
| then |
| if not Is_Library_Level_Entity (Id) then |
| Check_Restriction (No_Nested_Finalization, N); |
| else |
| Validate_Controlled_Object (Id); |
| end if; |
| |
| -- Generate a warning when an initialization causes an obvious ABE |
| -- violation. If the init expression is a simple aggregate there |
| -- shouldn't be any initialize/adjust call generated. This will be |
| -- true as soon as aggregates are built in place when possible. |
| |
| -- ??? at the moment we do not generate warnings for temporaries |
| -- created for those aggregates although Program_Error might be |
| -- generated if compiled with -gnato. |
| |
| if Is_Controlled (Etype (Id)) |
| and then Comes_From_Source (Id) |
| then |
| declare |
| BT : constant Entity_Id := Base_Type (Etype (Id)); |
| |
| Implicit_Call : Entity_Id; |
| pragma Warnings (Off, Implicit_Call); |
| -- ??? what is this for (never referenced!) |
| |
| function Is_Aggr (N : Node_Id) return Boolean; |
| -- Check that N is an aggregate |
| |
| ------------- |
| -- Is_Aggr -- |
| ------------- |
| |
| function Is_Aggr (N : Node_Id) return Boolean is |
| begin |
| case Nkind (Original_Node (N)) is |
| when N_Aggregate | N_Extension_Aggregate => |
| return True; |
| |
| when N_Qualified_Expression | |
| N_Type_Conversion | |
| N_Unchecked_Type_Conversion => |
| return Is_Aggr (Expression (Original_Node (N))); |
| |
| when others => |
| return False; |
| end case; |
| end Is_Aggr; |
| |
| begin |
| -- If no underlying type, we already are in an error situation. |
| -- Do not try to add a warning since we do not have access to |
| -- prim-op list. |
| |
| if No (Underlying_Type (BT)) then |
| Implicit_Call := Empty; |
| |
| -- A generic type does not have usable primitive operators. |
| -- Initialization calls are built for instances. |
| |
| elsif Is_Generic_Type (BT) then |
| Implicit_Call := Empty; |
| |
| -- If the init expression is not an aggregate, an adjust call |
| -- will be generated |
| |
| elsif Present (E) and then not Is_Aggr (E) then |
| Implicit_Call := Find_Prim_Op (BT, Name_Adjust); |
| |
| -- If no init expression and we are not in the deferred |
| -- constant case, an Initialize call will be generated |
| |
| elsif No (E) and then not Constant_Present (N) then |
| Implicit_Call := Find_Prim_Op (BT, Name_Initialize); |
| |
| else |
| Implicit_Call := Empty; |
| end if; |
| end; |
| end if; |
| end if; |
| |
| if Has_Task (Etype (Id)) then |
| Check_Restriction (No_Tasking, N); |
| |
| if Is_Library_Level_Entity (Id) then |
| Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id))); |
| else |
| Check_Restriction (Max_Tasks, N); |
| Check_Restriction (No_Task_Hierarchy, N); |
| Check_Potentially_Blocking_Operation (N); |
| end if; |
| |
| -- A rather specialized test. If we see two tasks being declared |
| -- of the same type in the same object declaration, and the task |
| -- has an entry with an address clause, we know that program error |
| -- will be raised at run-time since we can't have two tasks with |
| -- entries at the same address. |
| |
| if Is_Task_Type (Etype (Id)) and then More_Ids (N) then |
| declare |
| E : Entity_Id; |
| |
| begin |
| E := First_Entity (Etype (Id)); |
| while Present (E) loop |
| if Ekind (E) = E_Entry |
| and then Present (Get_Attribute_Definition_Clause |
| (E, Attribute_Address)) |
| then |
| Error_Msg_N |
| ("?more than one task with same entry address", N); |
| Error_Msg_N |
| ("\?Program_Error will be raised at run time", N); |
| Insert_Action (N, |
| Make_Raise_Program_Error (Loc, |
| Reason => PE_Duplicated_Entry_Address)); |
| exit; |
| end if; |
| |
| Next_Entity (E); |
| end loop; |
| end; |
| end if; |
| end if; |
| |
| -- Some simple constant-propagation: if the expression is a constant |
| -- string initialized with a literal, share the literal. This avoids |
| -- a run-time copy. |
| |
| if Present (E) |
| and then Is_Entity_Name (E) |
| and then Ekind (Entity (E)) = E_Constant |
| and then Base_Type (Etype (E)) = Standard_String |
| then |
| declare |
| Val : constant Node_Id := Constant_Value (Entity (E)); |
| begin |
| if Present (Val) |
| and then Nkind (Val) = N_String_Literal |
| then |
| Rewrite (E, New_Copy (Val)); |
| end if; |
| end; |
| end if; |
| |
| -- Another optimization: if the nominal subtype is unconstrained and |
| -- the expression is a function call that returns an unconstrained |
| -- type, rewrite the declaration as a renaming of the result of the |
| -- call. The exceptions below are cases where the copy is expected, |
| -- either by the back end (Aliased case) or by the semantics, as for |
| -- initializing controlled types or copying tags for classwide types. |
| |
| if Present (E) |
| and then Nkind (E) = N_Explicit_Dereference |
| and then Nkind (Original_Node (E)) = N_Function_Call |
| and then not Is_Library_Level_Entity (Id) |
| and then not Is_Constrained (Underlying_Type (T)) |
| and then not Is_Aliased (Id) |
| and then not Is_Class_Wide_Type (T) |
| and then not Is_Controlled (T) |
| and then not Has_Controlled_Component (Base_Type (T)) |
| and then Expander_Active |
| then |
| Rewrite (N, |
| Make_Object_Renaming_Declaration (Loc, |
| Defining_Identifier => Id, |
| Access_Definition => Empty, |
| Subtype_Mark => New_Occurrence_Of |
| (Base_Type (Etype (Id)), Loc), |
| Name => E)); |
| |
| Set_Renamed_Object (Id, E); |
| |
| -- Force generation of debugging information for the constant and for |
| -- the renamed function call. |
| |
| Set_Needs_Debug_Info (Id); |
| Set_Needs_Debug_Info (Entity (Prefix (E))); |
| end if; |
| |
| if Present (Prev_Entity) |
| and then Is_Frozen (Prev_Entity) |
| and then not Error_Posted (Id) |
| then |
| Error_Msg_N ("full constant declaration appears too late", N); |
| end if; |
| |
| Check_Eliminated (Id); |
| end Analyze_Object_Declaration; |
| |
| --------------------------- |
| -- Analyze_Others_Choice -- |
| --------------------------- |
| |
| -- Nothing to do for the others choice node itself, the semantic analysis |
| -- of the others choice will occur as part of the processing of the parent |
| |
| procedure Analyze_Others_Choice (N : Node_Id) is |
| pragma Warnings (Off, N); |
| begin |
| null; |
| end Analyze_Others_Choice; |
| |
| -------------------------------- |
| -- Analyze_Per_Use_Expression -- |
| -------------------------------- |
| |
| procedure Analyze_Per_Use_Expression (N : Node_Id; T : Entity_Id) is |
| Save_In_Default_Expression : constant Boolean := In_Default_Expression; |
| begin |
| In_Default_Expression := True; |
| Pre_Analyze_And_Resolve (N, T); |
| In_Default_Expression := Save_In_Default_Expression; |
| end Analyze_Per_Use_Expression; |
| |
| ------------------------------------------- |
| -- Analyze_Private_Extension_Declaration -- |
| ------------------------------------------- |
| |
| procedure Analyze_Private_Extension_Declaration (N : Node_Id) is |
| T : constant Entity_Id := Defining_Identifier (N); |
| Indic : constant Node_Id := Subtype_Indication (N); |
| Parent_Type : Entity_Id; |
| Parent_Base : Entity_Id; |
| |
| begin |
| -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces |
| |
| if Is_Non_Empty_List (Interface_List (N)) then |
| declare |
| Intf : Node_Id; |
| T : Entity_Id; |
| |
| begin |
| Intf := First (Interface_List (N)); |
| while Present (Intf) loop |
| T := Find_Type_Of_Subtype_Indic (Intf); |
| |
| if not Is_Interface (T) then |
| Error_Msg_NE ("(Ada 2005) & must be an interface", Intf, T); |
| end if; |
| |
| Next (Intf); |
| end loop; |
| end; |
| end if; |
| |
| Generate_Definition (T); |
| Enter_Name (T); |
| |
| Parent_Type := Find_Type_Of_Subtype_Indic (Indic); |
| Parent_Base := Base_Type (Parent_Type); |
| |
| if Parent_Type = Any_Type |
| or else Etype (Parent_Type) = Any_Type |
| then |
| Set_Ekind (T, Ekind (Parent_Type)); |
| Set_Etype (T, Any_Type); |
| return; |
| |
| elsif not Is_Tagged_Type (Parent_Type) then |
| Error_Msg_N |
| ("parent of type extension must be a tagged type ", Indic); |
| return; |
| |
| elsif Ekind (Parent_Type) = E_Void |
| or else Ekind (Parent_Type) = E_Incomplete_Type |
| then |
| Error_Msg_N ("premature derivation of incomplete type", Indic); |
| return; |
| end if; |
| |
| -- Perhaps the parent type should be changed to the class-wide type's |
| -- specific type in this case to prevent cascading errors ??? |
| |
| if Is_Class_Wide_Type (Parent_Type) then |
| Error_Msg_N |
| ("parent of type extension must not be a class-wide type", Indic); |
| return; |
| end if; |
| |
| if (not Is_Package_Or_Generic_Package (Current_Scope) |
| and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration) |
| or else In_Private_Part (Current_Scope) |
| |
| then |
| Error_Msg_N ("invalid context for private extension", N); |
| end if; |
| |
| -- Set common attributes |
| |
| Set_Is_Pure (T, Is_Pure (Current_Scope)); |
| Set_Scope (T, Current_Scope); |
| Set_Ekind (T, E_Record_Type_With_Private); |
| Init_Size_Align (T); |
| |
| Set_Etype (T, Parent_Base); |
| Set_Has_Task (T, Has_Task (Parent_Base)); |
| |
| Set_Convention (T, Convention (Parent_Type)); |
| Set_First_Rep_Item (T, First_Rep_Item (Parent_Type)); |
| Set_Is_First_Subtype (T); |
| Make_Class_Wide_Type (T); |
| |
| if Unknown_Discriminants_Present (N) then |
| Set_Discriminant_Constraint (T, No_Elist); |
| end if; |
| |
| Build_Derived_Record_Type (N, Parent_Type, T); |
| |
| if Limited_Present (N) then |
| Set_Is_Limited_Record (T); |
| |
| if not Is_Limited_Type (Parent_Type) |
| and then |
| (not Is_Interface (Parent_Type) |
| or else not Is_Limited_Interface (Parent_Type)) |
| then |
| Error_Msg_NE ("parent type& of limited extension must be limited", |
| N, Parent_Type); |
| end if; |
| end if; |
| end Analyze_Private_Extension_Declaration; |
| |
| --------------------------------- |
| -- Analyze_Subtype_Declaration -- |
| --------------------------------- |
| |
| procedure Analyze_Subtype_Declaration (N : Node_Id) is |
| Id : constant Entity_Id := Defining_Identifier (N); |
| T : Entity_Id; |
| R_Checks : Check_Result; |
| |
| begin |
| Generate_Definition (Id); |
| Set_Is_Pure (Id, Is_Pure (Current_Scope)); |
| Init_Size_Align (Id); |
| |
| -- The following guard condition on Enter_Name is to handle cases where |
| -- the defining identifier has already been entered into the scope but |
| -- the declaration as a whole needs to be analyzed. |
| |
| -- This case in particular happens for derived enumeration types. The |
| -- derived enumeration type is processed as an inserted enumeration type |
| -- declaration followed by a rewritten subtype declaration. The defining |
| -- identifier, however, is entered into the name scope very early in the |
| -- processing of the original type declaration and therefore needs to be |
| -- avoided here, when the created subtype declaration is analyzed. (See |
| -- Build_Derived_Types) |
| |
| -- This also happens when the full view of a private type is derived |
| -- type with constraints. In this case the entity has been introduced |
| -- in the private declaration. |
| |
| if Present (Etype (Id)) |
| and then (Is_Private_Type (Etype (Id)) |
| or else Is_Task_Type (Etype (Id)) |
| or else Is_Rewrite_Substitution (N)) |
| then |
| null; |
| |
| else |
| Enter_Name (Id); |
| end if; |
| |
| T := Process_Subtype (Subtype_Indication (N), N, Id, 'P'); |
| |
| -- Inherit common attributes |
| |
| Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T))); |
| Set_Is_Volatile (Id, Is_Volatile (T)); |
| Set_Treat_As_Volatile (Id, Treat_As_Volatile (T)); |
| Set_Is_Atomic (Id, Is_Atomic (T)); |
| Set_Is_Ada_2005 (Id, Is_Ada_2005 (T)); |
| |
| -- In the case where there is no constraint given in the subtype |
| -- indication, Process_Subtype just returns the Subtype_Mark, so its |
| -- semantic attributes must be established here. |
| |
| if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then |
| Set_Etype (Id, Base_Type (T)); |
| |
| case Ekind (T) is |
| when Array_Kind => |
| Set_Ekind (Id, E_Array_Subtype); |
| Copy_Array_Subtype_Attributes (Id, T); |
| |
| when Decimal_Fixed_Point_Kind => |
| Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype); |
| Set_Digits_Value (Id, Digits_Value (T)); |
| Set_Delta_Value (Id, Delta_Value (T)); |
| Set_Scale_Value (Id, Scale_Value (T)); |
| Set_Small_Value (Id, Small_Value (T)); |
| Set_Scalar_Range (Id, Scalar_Range (T)); |
| Set_Machine_Radix_10 (Id, Machine_Radix_10 (T)); |
| Set_Is_Constrained (Id, Is_Constrained (T)); |
| Set_RM_Size (Id, RM_Size (T)); |
| |
| when Enumeration_Kind => |
| Set_Ekind (Id, E_Enumeration_Subtype); |
| Set_First_Literal (Id, First_Literal (Base_Type (T))); |
| Set_Scalar_Range (Id, Scalar_Range (T)); |
| Set_Is_Character_Type (Id, Is_Character_Type (T)); |
| Set_Is_Constrained (Id, Is_Constrained (T)); |
| Set_RM_Size (Id, RM_Size (T)); |
| |
| when Ordinary_Fixed_Point_Kind => |
| Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype); |
| Set_Scalar_Range (Id, Scalar_Range (T)); |
| Set_Small_Value (Id, Small_Value (T)); |
| Set_Delta_Value (Id, Delta_Value (T)); |
| Set_Is_Constrained (Id, Is_Constrained (T)); |
| Set_RM_Size (Id, RM_Size (T)); |
| |
| when Float_Kind => |
| Set_Ekind (Id, E_Floating_Point_Subtype); |
| Set_Scalar_Range (Id, Scalar_Range (T)); |
| Set_Digits_Value (Id, Digits_Value (T)); |
| Set_Is_Constrained (Id, Is_Constrained (T)); |
| |
| when Signed_Integer_Kind => |
| Set_Ekind (Id, E_Signed_Integer_Subtype); |
| Set_Scalar_Range (Id, Scalar_Range (T)); |
| Set_Is_Constrained (Id, Is_Constrained (T)); |
| Set_RM_Size (Id, RM_Size (T)); |
| |
| when Modular_Integer_Kind => |
| Set_Ekind (Id, E_Modular_Integer_Subtype); |
| Set_Scalar_Range (Id, Scalar_Range (T)); |
| Set_Is_Constrained (Id, Is_Constrained (T)); |
| Set_RM_Size (Id, RM_Size (T)); |
| |
| when Class_Wide_Kind => |
| Set_Ekind (Id, E_Class_Wide_Subtype); |
| Set_First_Entity (Id, First_Entity (T)); |
| Set_Last_Entity (Id, Last_Entity (T)); |
| Set_Class_Wide_Type (Id, Class_Wide_Type (T)); |
| Set_Cloned_Subtype (Id, T); |
| Set_Is_Tagged_Type (Id, True); |
| Set_Has_Unknown_Discriminants |
| (Id, True); |
| |
| if Ekind (T) = E_Class_Wide_Subtype then |
| Set_Equivalent_Type (Id, Equivalent_Type (T)); |
| end if; |
| |
| when E_Record_Type | E_Record_Subtype => |
| Set_Ekind (Id, E_Record_Subtype); |
| |
| if Ekind (T) = E_Record_Subtype |
| and then Present (Cloned_Subtype (T)) |
| then |
| Set_Cloned_Subtype (Id, Cloned_Subtype (T)); |
| else |
| Set_Cloned_Subtype (Id, T); |
| end if; |
| |
| Set_First_Entity (Id, First_Entity (T)); |
| Set_Last_Entity (Id, Last_Entity (T)); |
| Set_Has_Discriminants (Id, Has_Discriminants (T)); |
| Set_Is_Constrained (Id, Is_Constrained (T)); |
| Set_Is_Limited_Record (Id, Is_Limited_Record (T)); |
| Set_Has_Unknown_Discriminants |
| (Id, Has_Unknown_Discriminants (T)); |
| |
| if Has_Discriminants (T) then |
| Set_Discriminant_Constraint |
| (Id, Discriminant_Constraint (T)); |
| Set_Stored_Constraint_From_Discriminant_Constraint (Id); |
| |
| elsif Has_Unknown_Discriminants (Id) then |
| Set_Discriminant_Constraint (Id, No_Elist); |
| end if; |
| |
| if Is_Tagged_Type (T) then |
| Set_Is_Tagged_Type (Id); |
| Set_Is_Abstract (Id, Is_Abstract (T)); |
| Set_Primitive_Operations |
| (Id, Primitive_Operations (T)); |
| Set_Class_Wide_Type (Id, Class_Wide_Type (T)); |
| end if; |
| |
| when Private_Kind => |
| Set_Ekind (Id, Subtype_Kind (Ekind (T))); |
| Set_Has_Discriminants (Id, Has_Discriminants (T)); |
| Set_Is_Constrained (Id, Is_Constrained (T)); |
| Set_First_Entity (Id, First_Entity (T)); |
| Set_Last_Entity (Id, Last_Entity (T)); |
| Set_Private_Dependents (Id, New_Elmt_List); |
| Set_Is_Limited_Record (Id, Is_Limited_Record (T)); |
| Set_Has_Unknown_Discriminants |
| (Id, Has_Unknown_Discriminants (T)); |
| |
| if Is_Tagged_Type (T) then |
| Set_Is_Tagged_Type (Id); |
| Set_Is_Abstract (Id, Is_Abstract (T)); |
| Set_Primitive_Operations |
| (Id, Primitive_Operations (T)); |
| Set_Class_Wide_Type (Id, Class_Wide_Type (T)); |
| end if; |
| |
| -- In general the attributes of the subtype of a private type |
| -- are the attributes of the partial view of parent. However, |
| -- the full view may be a discriminated type, and the subtype |
| -- must share the discriminant constraint to generate correct |
| -- calls to initialization procedures. |
| |
| if Has_Discriminants (T) then |
| Set_Discriminant_Constraint |
| (Id, Discriminant_Constraint (T)); |
| Set_Stored_Constraint_From_Discriminant_Constraint (Id); |
| |
| elsif Present (Full_View (T)) |
| and then Has_Discriminants (Full_View (T)) |
| then |
| Set_Discriminant_Constraint |
| (Id, Discriminant_Constraint (Full_View (T))); |
| Set_Stored_Constraint_From_Discriminant_Constraint (Id); |
| |
| -- This would seem semantically correct, but apparently |
| -- confuses the back-end (4412-009). To be explained ??? |
| |
| -- Set_Has_Discriminants (Id); |
| end if; |
| |
| Prepare_Private_Subtype_Completion (Id, N); |
| |
| when Access_Kind => |
| Set_Ekind (Id, E_Access_Subtype); |
| Set_Is_Constrained (Id, Is_Constrained (T)); |
| Set_Is_Access_Constant |
| (Id, Is_Access_Constant (T)); |
| Set_Directly_Designated_Type |
| (Id, Designated_Type (T)); |
| Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T)); |
| |
| -- A Pure library_item must not contain the declaration of a |
| -- named access type, except within a subprogram, generic |
| -- subprogram, task unit, or protected unit (RM 10.2.1(16)). |
| |
| if Comes_From_Source (Id) |
| and then In_Pure_Unit |
| and then not In_Subprogram_Task_Protected_Unit |
| then |
| Error_Msg_N |
| ("named access types not allowed in pure unit", N); |
| end if; |
| |
| when Concurrent_Kind => |
| Set_Ekind (Id, Subtype_Kind (Ekind (T))); |
| Set_Corresponding_Record_Type (Id, |
| Corresponding_Record_Type (T)); |
| Set_First_Entity (Id, First_Entity (T)); |
| Set_First_Private_Entity (Id, First_Private_Entity (T)); |
| Set_Has_Discriminants (Id, Has_Discriminants (T)); |
| Set_Is_Constrained (Id, Is_Constrained (T)); |
| Set_Last_Entity (Id, Last_Entity (T)); |
| |
| if Has_Discriminants (T) then |
| Set_Discriminant_Constraint (Id, |
| Discriminant_Constraint (T)); |
| Set_Stored_Constraint_From_Discriminant_Constraint (Id); |
| end if; |
| |
| -- If the subtype name denotes an incomplete type an error was |
| -- already reported by Process_Subtype. |
| |
| when E_Incomplete_Type => |
| Set_Etype (Id, Any_Type); |
| |
| when others => |
| raise Program_Error; |
| end case; |
| end if; |
| |
| if Etype (Id) = Any_Type then |
| return; |
| end if; |
| |
| -- Some common processing on all types |
| |
| Set_Size_Info (Id, T); |
| Set_First_Rep_Item (Id, First_Rep_Item (T)); |
| |
| T := Etype (Id); |
| |
| Set_Is_Immediately_Visible (Id, True); |
| Set_Depends_On_Private (Id, Has_Private_Component (T)); |
| |
| if Present (Generic_Parent_Type (N)) |
| and then |
| (Nkind |
| (Parent (Generic_Parent_Type (N))) /= N_Formal_Type_Declaration |
| or else Nkind |
| (Formal_Type_Definition (Parent (Generic_Parent_Type (N)))) |
| /= N_Formal_Private_Type_Definition) |
| then |
| if Is_Tagged_Type (Id) then |
| if Is_Class_Wide_Type (Id) then |
| Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T)); |
| else |
| Derive_Subprograms (Generic_Parent_Type (N), Id, T); |
| end if; |
| |
| elsif Scope (Etype (Id)) /= Standard_Standard then |
| Derive_Subprograms (Generic_Parent_Type (N), Id); |
| end if; |
| end if; |
| |
| if Is_Private_Type (T) |
| and then Present (Full_View (T)) |
| then |
| Conditional_Delay (Id, Full_View (T)); |
| |
| -- The subtypes of components or subcomponents of protected types |
| -- do not need freeze nodes, which would otherwise appear in the |
| -- wrong scope (before the freeze node for the protected type). The |
| -- proper subtypes are those of the subcomponents of the corresponding |
| -- record. |
| |
| elsif Ekind (Scope (Id)) /= E_Protected_Type |
| and then Present (Scope (Scope (Id))) -- error defense! |
| and then Ekind (Scope (Scope (Id))) /= E_Protected_Type |
| then |
| Conditional_Delay (Id, T); |
| end if; |
| |
| -- Check that constraint_error is raised for a scalar subtype |
| -- indication when the lower or upper bound of a non-null range |
| -- lies outside the range of the type mark. |
| |
| if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then |
| if Is_Scalar_Type (Etype (Id)) |
| and then Scalar_Range (Id) /= |
| Scalar_Range (Etype (Subtype_Mark |
| (Subtype_Indication (N)))) |
| then |
| Apply_Range_Check |
| (Scalar_Range (Id), |
| Etype (Subtype_Mark (Subtype_Indication (N)))); |
| |
| elsif Is_Array_Type (Etype (Id)) |
| and then Present (First_Index (Id)) |
| then |
| -- This really should be a subprogram that finds the indications |
| -- to check??? |
| |
| if ((Nkind (First_Index (Id)) = N_Identifier |
| and then Ekind (Entity (First_Index (Id))) in Scalar_Kind) |
| or else Nkind (First_Index (Id)) = N_Subtype_Indication) |
| and then |
| Nkind (Scalar_Range (Etype (First_Index (Id)))) = N_Range |
| then |
| declare |
| Target_Typ : constant Entity_Id := |
| Etype |
| (First_Index (Etype |
| (Subtype_Mark (Subtype_Indication (N))))); |
| begin |
| R_Checks := |
| Range_Check |
| (Scalar_Range (Etype (First_Index (Id))), |
| Target_Typ, |
| Etype (First_Index (Id)), |
| Defining_Identifier (N)); |
| |
| Insert_Range_Checks |
| (R_Checks, |
| N, |
| Target_Typ, |
| Sloc (Defining_Identifier (N))); |
| end; |
| end if; |
| end if; |
| end if; |
| |
| Check_Eliminated (Id); |
| end Analyze_Subtype_Declaration; |
| |
| -------------------------------- |
| -- Analyze_Subtype_Indication -- |
| -------------------------------- |
| |
| procedure Analyze_Subtype_Indication (N : Node_Id) is |
| T : constant Entity_Id := Subtype_Mark (N); |
| R : constant Node_Id := Range_Expression (Constraint (N)); |
| |
| begin |
| Analyze (T); |
| |
| if R /= Error then |
| Analyze (R); |
| Set_Etype (N, Etype (R)); |
| else |
| Set_Error_Posted (R); |
| Set_Error_Posted (T); |
| end if; |
| end Analyze_Subtype_Indication; |
| |
| ------------------------------ |
| -- Analyze_Type_Declaration -- |
| ------------------------------ |
| |
| procedure Analyze_Type_Declaration (N : Node_Id) is |
| Def : constant Node_Id := Type_Definition (N); |
| Def_Id : constant Entity_Id := Defining_Identifier (N); |
| T : Entity_Id; |
| Prev : Entity_Id; |
| |
| Is_Remote : constant Boolean := |
| (Is_Remote_Types (Current_Scope) |
| or else Is_Remote_Call_Interface (Current_Scope)) |
| and then not (In_Private_Part (Current_Scope) |
| or else |
| In_Package_Body (Current_Scope)); |
| |
| procedure Check_Ops_From_Incomplete_Type; |
| -- If there is a tagged incomplete partial view of the type, transfer |
| -- its operations to the full view, and indicate that the type of the |
| -- controlling parameter (s) is this full view. |
| |
| ------------------------------------ |
| -- Check_Ops_From_Incomplete_Type -- |
| ------------------------------------ |
| |
| procedure Check_Ops_From_Incomplete_Type is |
| Elmt : Elmt_Id; |
| Formal : Entity_Id; |
| Op : Entity_Id; |
| |
| begin |
| if Prev /= T |
| and then Ekind (Prev) = E_Incomplete_Type |
| and then Is_Tagged_Type (Prev) |
| and then Is_Tagged_Type (T) |
| then |
| Elmt := First_Elmt (Primitive_Operations (Prev)); |
| while Present (Elmt) loop |
| Op := Node (Elmt); |
| Prepend_Elmt (Op, Primitive_Operations (T)); |
| |
| Formal := First_Formal (Op); |
| while Present (Formal) loop |
| if Etype (Formal) = Prev then |
| Set_Etype (Formal, T); |
| end if; |
| |
| Next_Formal (Formal); |
| end loop; |
| |
| if Etype (Op) = Prev then |
| Set_Etype (Op, T); |
| end if; |
| |
| Next_Elmt (Elmt); |
| end loop; |
| end if; |
| end Check_Ops_From_Incomplete_Type; |
| |
| -- Start of processing for Analyze_Type_Declaration |
| |
| begin |
| Prev := Find_Type_Name (N); |
| |
| -- The full view, if present, now points to the current type |
| |
| -- Ada 2005 (AI-50217): If the type was previously decorated when |
| -- imported through a LIMITED WITH clause, it appears as incomplete |
| -- but has no full view. |
| |
| if Ekind (Prev) = E_Incomplete_Type |
| and then Present (Full_View (Prev)) |
| then |
| T := Full_View (Prev); |
| else |
| T := Prev; |
| end if; |
| |
| Set_Is_Pure (T, Is_Pure (Current_Scope)); |
| |
| -- We set the flag Is_First_Subtype here. It is needed to set the |
| -- corresponding flag for the Implicit class-wide-type created |
| -- during tagged types processing. |
| |
| Set_Is_First_Subtype (T, True); |
| |
| -- Only composite types other than array types are allowed to have |
| -- discriminants. |
| |
| case Nkind (Def) is |
| |
| -- For derived types, the rule will be checked once we've figured |
| -- out the parent type. |
| |
| when N_Derived_Type_Definition => |
| null; |
| |
| -- For record types, discriminants are allowed |
| |
| when N_Record_Definition => |
| null; |
| |
| when others => |
| if Present (Discriminant_Specifications (N)) then |
| Error_Msg_N |
| ("elementary or array type cannot have discriminants", |
| Defining_Identifier |
| (First (Discriminant_Specifications (N)))); |
| end if; |
| end case; |
| |
| -- Elaborate the type definition according to kind, and generate |
| -- subsidiary (implicit) subtypes where needed. We skip this if |
| -- it was already done (this happens during the reanalysis that |
| -- follows a call to the high level optimizer). |
| |
| if not Analyzed (T) then |
| Set_Analyzed (T); |
| |
| case Nkind (Def) is |
| |
| when N_Access_To_Subprogram_Definition => |
| Access_Subprogram_Declaration (T, Def); |
| |
| -- If this is a remote access to subprogram, we must create |
| -- the equivalent fat pointer type, and related subprograms. |
| |
| if Is_Remote then |
| Process_Remote_AST_Declaration (N); |
| end if; |
| |
| -- Validate categorization rule against access type declaration |
| -- usually a violation in Pure unit, Shared_Passive unit. |
| |
| Validate_Access_Type_Declaration (T, N); |
| |
| when N_Access_To_Object_Definition => |
| Access_Type_Declaration (T, Def); |
| |
| -- Validate categorization rule against access type declaration |
| -- usually a violation in Pure unit, Shared_Passive unit. |
| |
| Validate_Access_Type_Declaration (T, N); |
| |
| -- If we are in a Remote_Call_Interface package and define |
| -- a RACW, Read and Write attribute must be added. |
| |
| if Is_Remote |
| and then Is_Remote_Access_To_Class_Wide_Type (Def_Id) |
| then |
| Add_RACW_Features (Def_Id); |
| end if; |
| |
| -- Set no strict aliasing flag if config pragma seen |
| |
| if Opt.No_Strict_Aliasing then |
| Set_No_Strict_Aliasing (Base_Type (Def_Id)); |
| end if; |
| |
| when N_Array_Type_Definition => |
| Array_Type_Declaration (T, Def); |
| |
| when N_Derived_Type_Definition => |
| Derived_Type_Declaration (T, N, T /= Def_Id); |
| |
| when N_Enumeration_Type_Definition => |
| Enumeration_Type_Declaration (T, Def); |
| |
| when N_Floating_Point_Definition => |
| Floating_Point_Type_Declaration (T, Def); |
| |
| when N_Decimal_Fixed_Point_Definition => |
| Decimal_Fixed_Point_Type_Declaration (T, Def); |
| |
| when N_Ordinary_Fixed_Point_Definition => |
| Ordinary_Fixed_Point_Type_Declaration (T, Def); |
| |
| when N_Signed_Integer_Type_Definition => |
| Signed_Integer_Type_Declaration (T, Def); |
| |
| when N_Modular_Type_Definition => |
| Modular_Type_Declaration (T, Def); |
| |
| when N_Record_Definition => |
| Record_Type_Declaration (T, N, Prev); |
| |
| when others => |
| raise Program_Error; |
| |
| end case; |
| end if; |
| |
| if Etype (T) = Any_Type then |
| return; |
| end if; |
| |
| -- Some common processing for all types |
| |
| Set_Depends_On_Private (T, Has_Private_Component (T)); |
| Check_Ops_From_Incomplete_Type; |
| |
| -- Both the declared entity, and its anonymous base type if one |
| -- was created, need freeze nodes allocated. |
| |
| declare |
| B : constant Entity_Id := Base_Type (T); |
| |
| begin |
| -- In the case where the base type is different from the first |
| -- subtype, we pre-allocate a freeze node, and set the proper link |
| -- to the first subtype. Freeze_Entity will use this preallocated |
| -- freeze node when it freezes the entity. |
| |
| if B /= T then |
| Ensure_Freeze_Node (B); |
| Set_First_Subtype_Link (Freeze_Node (B), T); |
| end if; |
| |
| if not From_With_Type (T) then |
| Set_Has_Delayed_Freeze (T); |
| end if; |
| end; |
| |
| -- Case of T is the full declaration of some private type which has |
| -- been swapped in Defining_Identifier (N). |
| |
| if T /= Def_Id and then Is_Private_Type (Def_Id) then |
| Process_Full_View (N, T, Def_Id); |
| |
| -- Record the reference. The form of this is a little strange, |
| -- since the full declaration has been swapped in. So the first |
| -- parameter here represents the entity to which a reference is |
| -- made which is the "real" entity, i.e. the one swapped in, |
| -- and the second parameter provides the reference location. |
| |
| Generate_Reference (T, T, 'c'); |
| Set_Completion_Referenced (Def_Id); |
| |
| -- For completion of incomplete type, process incomplete dependents |
| -- and always mark the full type as referenced (it is the incomplete |
| -- type that we get for any real reference). |
| |
| elsif Ekind (Prev) = E_Incomplete_Type then |
| Process_Incomplete_Dependents (N, T, Prev); |
| Generate_Reference (Prev, Def_Id, 'c'); |
| Set_Completion_Referenced (Def_Id); |
| |
| -- If not private type or incomplete type completion, this is a real |
| -- definition of a new entity, so record it. |
| |
| else |
| Generate_Definition (Def_Id); |
| end if; |
| |
| Check_Eliminated (Def_Id); |
| end Analyze_Type_Declaration; |
| |
| -------------------------- |
| -- Analyze_Variant_Part -- |
| -------------------------- |
| |
| procedure Analyze_Variant_Part (N : Node_Id) is |
| |
| procedure Non_Static_Choice_Error (Choice : Node_Id); |
| -- Error routine invoked by the generic instantiation below when |
| -- the variant part has a non static choice. |
| |
| procedure Process_Declarations (Variant : Node_Id); |
| -- Analyzes all the declarations associated with a Variant. |
| -- Needed by the generic instantiation below. |
| |
| package Variant_Choices_Processing is new |
| Generic_Choices_Processing |
| (Get_Alternatives => Variants, |
| Get_Choices => Discrete_Choices, |
| Process_Empty_Choice => No_OP, |
| Process_Non_Static_Choice => Non_Static_Choice_Error, |
| Process_Associated_Node => Process_Declarations); |
| use Variant_Choices_Processing; |
| -- Instantiation of the generic choice processing package |
| |
| ----------------------------- |
| -- Non_Static_Choice_Error -- |
| ----------------------------- |
| |
| procedure Non_Static_Choice_Error (Choice : Node_Id) is |
| begin |
| Flag_Non_Static_Expr |
| ("choice given in variant part is not static!", Choice); |
| end Non_Static_Choice_Error; |
| |
| -------------------------- |
| -- Process_Declarations -- |
| -------------------------- |
| |
| procedure Process_Declarations (Variant : Node_Id) is |
| begin |
| if not Null_Present (Component_List (Variant)) then |
| Analyze_Declarations (Component_Items (Component_List (Variant))); |
| |
| if Present (Variant_Part (Component_List (Variant))) then |
| Analyze (Variant_Part (Component_List (Variant))); |
| end if; |
| end if; |
| end Process_Declarations; |
| |
| -- Variables local to Analyze_Case_Statement |
| |
| Discr_Name : Node_Id; |
| Discr_Type : Entity_Id; |
| |
| Case_Table : Choice_Table_Type (1 .. Number_Of_Choices (N)); |
| Last_Choice : Nat; |
| Dont_Care : Boolean; |
| Others_Present : Boolean := False; |
| |
| -- Start of processing for Analyze_Variant_Part |
| |
| begin |
| Discr_Name := Name (N); |
| Analyze (Discr_Name); |
| |
| if Ekind (Entity (Discr_Name)) /= E_Discriminant then |
| Error_Msg_N ("invalid discriminant name in variant part", Discr_Name); |
| end if; |
| |
| Discr_Type := Etype (Entity (Discr_Name)); |
| |
| if not Is_Discrete_Type (Discr_Type) then |
| Error_Msg_N |
| ("discriminant in a variant part must be of a discrete type", |
| Name (N)); |
| return; |
| end if; |
| |
| -- Call the instantiated Analyze_Choices which does the rest of the work |
| |
| Analyze_Choices |
| (N, Discr_Type, Case_Table, Last_Choice, Dont_Care, Others_Present); |
| end Analyze_Variant_Part; |
| |
| ---------------------------- |
| -- Array_Type_Declaration -- |
| ---------------------------- |
| |
| procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is |
| Component_Def : constant Node_Id := Component_Definition (Def); |
| Element_Type : Entity_Id; |
| Implicit_Base : Entity_Id; |
| Index : Node_Id; |
| Related_Id : Entity_Id := Empty; |
| Nb_Index : Nat; |
| P : constant Node_Id := Parent (Def); |
| Priv : Entity_Id; |
| |
| begin |
| if Nkind (Def) = N_Constrained_Array_Definition then |
| Index := First (Discrete_Subtype_Definitions (Def)); |
| else |
| Index := First (Subtype_Marks (Def)); |
| end if; |
| |
| -- Find proper names for the implicit types which may be public. |
| -- in case of anonymous arrays we use the name of the first object |
| -- of that type as prefix. |
| |
| if No (T) then |
| Related_Id := Defining_Identifier (P); |
| else |
| Related_Id := T; |
| end if; |
| |
| Nb_Index := 1; |
| while Present (Index) loop |
| Analyze (Index); |
| Make_Index (Index, P, Related_Id, Nb_Index); |
| Next_Index (Index); |
| Nb_Index := Nb_Index + 1; |
| end loop; |
| |
| if Present (Subtype_Indication (Component_Def)) then |
| Element_Type := Process_Subtype (Subtype_Indication (Component_Def), |
| P, Related_Id, 'C'); |
| |
| -- Ada 2005 (AI-230): Access Definition case |
| |
| else pragma Assert (Present (Access_Definition (Component_Def))); |
| Element_Type := Access_Definition |
| (Related_Nod => Related_Id, |
| N => Access_Definition (Component_Def)); |
| Set_Is_Local_Anonymous_Access (Element_Type); |
| |
| -- Ada 2005 (AI-230): In case of components that are anonymous |
| -- access types the level of accessibility depends on the enclosing |
| -- type declaration |
| |
| Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230) |
| |
| -- Ada 2005 (AI-254) |
| |
| declare |
| CD : constant Node_Id := |
| Access_To_Subprogram_Definition |
| (Access_Definition (Component_Def)); |
| begin |
| if Present (CD) and then Protected_Present (CD) then |
| Element_Type := |
| Replace_Anonymous_Access_To_Protected_Subprogram |
| (Def, Element_Type); |
| end if; |
| end; |
| end if; |
| |
| -- Constrained array case |
| |
| if No (T) then |
| T := Create_Itype (E_Void, P, Related_Id, 'T'); |
| end if; |
| |
| if Nkind (Def) = N_Constrained_Array_Definition then |
| |
| -- Establish Implicit_Base as unconstrained base type |
| |
| Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B'); |
| |
| Init_Size_Align (Implicit_Base); |
| Set_Etype (Implicit_Base, Implicit_Base); |
| Set_Scope (Implicit_Base, Current_Scope); |
| Set_Has_Delayed_Freeze (Implicit_Base); |
| |
| -- The constrained array type is a subtype of the unconstrained one |
| |
| Set_Ekind (T, E_Array_Subtype); |
| Init_Size_Align (T); |
| Set_Etype (T, Implicit_Base); |
| Set_Scope (T, Current_Scope); |
| Set_Is_Constrained (T, True); |
| Set_First_Index (T, First (Discrete_Subtype_Definitions (Def))); |
| Set_Has_Delayed_Freeze (T); |
| |
| -- Complete setup of implicit base type |
| |
| Set_First_Index (Implicit_Base, First_Index (T)); |
| Set_Component_Type (Implicit_Base, Element_Type); |
| Set_Has_Task (Implicit_Base, Has_Task (Element_Type)); |
| Set_Component_Size (Implicit_Base, Uint_0); |
| Set_Has_Controlled_Component |
| (Implicit_Base, Has_Controlled_Component |
| (Element_Type) |
| or else |
| Is_Controlled (Element_Type)); |
| Set_Finalize_Storage_Only |
| (Implicit_Base, Finalize_Storage_Only |
| (Element_Type)); |
| |
| -- Unconstrained array case |
| |
| else |
| Set_Ekind (T, E_Array_Type); |
| Init_Size_Align (T); |
| Set_Etype (T, T); |
| Set_Scope (T, Current_Scope); |
| Set_Component_Size (T, Uint_0); |
| Set_Is_Constrained (T, False); |
| Set_First_Index (T, First (Subtype_Marks (Def))); |
| Set_Has_Delayed_Freeze (T, True); |
| Set_Has_Task (T, Has_Task (Element_Type)); |
| Set_Has_Controlled_Component (T, Has_Controlled_Component |
| (Element_Type) |
| or else |
| Is_Controlled (Element_Type)); |
| Set_Finalize_Storage_Only (T, Finalize_Storage_Only |
| (Element_Type)); |
| end if; |
| |
| Set_Component_Type (Base_Type (T), Element_Type); |
| |
| if Aliased_Present (Component_Definition (Def)) then |
| Set_Has_Aliased_Components (Etype (T)); |
| end if; |
| |
| -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the |
| -- array type to ensure that objects of this type are initialized. |
| |
| if Ada_Version >= Ada_05 |
| and then Can_Never_Be_Null (Element_Type) |
| then |
| Set_Can_Never_Be_Null (T); |
| |
| if Null_Exclusion_Present (Component_Definition (Def)) |
| and then Can_Never_Be_Null (Element_Type) |
| |
| -- No need to check itypes because in their case this check |
| -- was done at their point of creation |
| |
| and then not Is_Itype (Element_Type) |
| then |
| Error_Msg_N |
| ("(Ada 2005) already a null-excluding type", |
| Subtype_Indication (Component_Definition (Def))); |
| end if; |
| end if; |
| |
| Priv := Private_Component (Element_Type); |
| |
| if Present (Priv) then |
| |
| -- Check for circular definitions |
| |
| if Priv = Any_Type then |
| Set_Component_Type (Etype (T), Any_Type); |
| |
| -- There is a gap in the visibility of operations on the composite |
| -- type only if the component type is defined in a different scope. |
| |
| elsif Scope (Priv) = Current_Scope then |
| null; |
| |
| elsif Is_Limited_Type (Priv) then |
| Set_Is_Limited_Composite (Etype (T)); |
| Set_Is_Limited_Composite (T); |
| else |
| Set_Is_Private_Composite (Etype (T)); |
| Set_Is_Private_Composite (T); |
| end if; |
| end if; |
| |
| -- Create a concatenation operator for the new type. Internal |
| -- array types created for packed entities do not need such, they |
| -- are compatible with the user-defined type. |
| |
| if Number_Dimensions (T) = 1 |
| and then not Is_Packed_Array_Type (T) |
| then |
| New_Concatenation_Op (T); |
| end if; |
| |
| -- In the case of an unconstrained array the parser has already |
| -- verified that all the indices are unconstrained but we still |
| -- need to make sure that the element type is constrained. |
| |
| if Is_Indefinite_Subtype (Element_Type) then |
| Error_Msg_N |
| ("unconstrained element type in array declaration", |
| Subtype_Indication (Component_Def)); |
| |
| elsif Is_Abstract (Element_Type) then |
| Error_Msg_N |
| ("the type of a component cannot be abstract", |
| Subtype_Indication (Component_Def)); |
| end if; |
| |
| end Array_Type_Declaration; |
| |
| ------------------------------------------------------ |
| -- Replace_Anonymous_Access_To_Protected_Subprogram -- |
| ------------------------------------------------------ |
| |
| function Replace_Anonymous_Access_To_Protected_Subprogram |
| (N : Node_Id; |
| Prev_E : Entity_Id) return Entity_Id |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| |
| Curr_Scope : constant Scope_Stack_Entry := |
| Scope_Stack.Table (Scope_Stack.Last); |
| |
| Anon : constant Entity_Id := |
| Make_Defining_Identifier (Loc, |
| Chars => New_Internal_Name ('S')); |
| |
| Acc : Node_Id; |
| Comp : Node_Id; |
| Decl : Node_Id; |
| P : Node_Id; |
| |
| begin |
| Set_Is_Internal (Anon); |
| |
| case Nkind (N) is |
| when N_Component_Declaration | |
| N_Unconstrained_Array_Definition | |
| N_Constrained_Array_Definition => |
| Comp := Component_Definition (N); |
| Acc := Access_Definition (Component_Definition (N)); |
| |
| when N_Discriminant_Specification => |
| Comp := Discriminant_Type (N); |
| Acc := Discriminant_Type (N); |
| |
| when N_Parameter_Specification => |
| Comp := Parameter_Type (N); |
| Acc := Parameter_Type (N); |
| |
| when others => |
| raise Program_Error; |
| end case; |
| |
| Decl := Make_Full_Type_Declaration (Loc, |
| Defining_Identifier => Anon, |
| Type_Definition => |
| Copy_Separate_Tree (Access_To_Subprogram_Definition (Acc))); |
| |
| Mark_Rewrite_Insertion (Decl); |
| |
| -- Insert the new declaration in the nearest enclosing scope |
| |
| P := Parent (N); |
| while Present (P) and then not Has_Declarations (P) loop |
| P := Parent (P); |
| end loop; |
| |
| pragma Assert (Present (P)); |
| |
| if Nkind (P) = N_Package_Specification then |
| Prepend (Decl, Visible_Declarations (P)); |
| else |
| Prepend (Decl, Declarations (P)); |
| end if; |
| |
| -- Replace the anonymous type with an occurrence of the new declaration. |
| -- In all cases the rewritten node does not have the null-exclusion |
| -- attribute because (if present) it was already inherited by the |
| -- anonymous entity (Anon). Thus, in case of components we do not |
| -- inherit this attribute. |
| |
| if Nkind (N) = N_Parameter_Specification then |
| Rewrite (Comp, New_Occurrence_Of (Anon, Loc)); |
| Set_Etype (Defining_Identifier (N), Anon); |
| Set_Null_Exclusion_Present (N, False); |
| else |
| Rewrite (Comp, |
| Make_Component_Definition (Loc, |
| Subtype_Indication => New_Occurrence_Of (Anon, Loc))); |
| end if; |
| |
| Mark_Rewrite_Insertion (Comp); |
| |
| -- Temporarily remove the current scope from the stack to add the new |
| -- declarations to the enclosing scope |
| |
| Scope_Stack.Decrement_Last; |
| Analyze (Decl); |
| Scope_Stack.Append (Curr_Scope); |
| |
| Set_Original_Access_Type (Anon, Prev_E); |
| return Anon; |
| end Replace_Anonymous_Access_To_Protected_Subprogram; |
| |
| ------------------------------- |
| -- Build_Derived_Access_Type -- |
| ------------------------------- |
| |
| procedure Build_Derived_Access_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id) |
| is |
| S : constant Node_Id := Subtype_Indication (Type_Definition (N)); |
| |
| Desig_Type : Entity_Id; |
| Discr : Entity_Id; |
| Discr_Con_Elist : Elist_Id; |
| Discr_Con_El : Elmt_Id; |
| Subt : Entity_Id; |
| |
| begin |
| -- Set the designated type so it is available in case this is |
| -- an access to a self-referential type, e.g. a standard list |
| -- type with a next pointer. Will be reset after subtype is built. |
| |
| Set_Directly_Designated_Type |
| (Derived_Type, Designated_Type (Parent_Type)); |
| |
| Subt := Process_Subtype (S, N); |
| |
| if Nkind (S) /= N_Subtype_Indication |
| and then Subt /= Base_Type (Subt) |
| then |
| Set_Ekind (Derived_Type, E_Access_Subtype); |
| end if; |
| |
| if Ekind (Derived_Type) = E_Access_Subtype then |
| declare |
| Pbase : constant Entity_Id := Base_Type (Parent_Type); |
| Ibase : constant Entity_Id := |
| Create_Itype (Ekind (Pbase), N, Derived_Type, 'B'); |
| Svg_Chars : constant Name_Id := Chars (Ibase); |
| Svg_Next_E : constant Entity_Id := Next_Entity (Ibase); |
| |
| begin |
| Copy_Node (Pbase, Ibase); |
| |
| Set_Chars (Ibase, Svg_Chars); |
| Set_Next_Entity (Ibase, Svg_Next_E); |
| Set_Sloc (Ibase, Sloc (Derived_Type)); |
| Set_Scope (Ibase, Scope (Derived_Type)); |
| Set_Freeze_Node (Ibase, Empty); |
| Set_Is_Frozen (Ibase, False); |
| Set_Comes_From_Source (Ibase, False); |
| Set_Is_First_Subtype (Ibase, False); |
| |
| Set_Etype (Ibase, Pbase); |
| Set_Etype (Derived_Type, Ibase); |
| end; |
| end if; |
| |
| Set_Directly_Designated_Type |
| (Derived_Type, Designated_Type (Subt)); |
| |
| Set_Is_Constrained (Derived_Type, Is_Constrained (Subt)); |
| Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type)); |
| Set_Size_Info (Derived_Type, Parent_Type); |
| Set_RM_Size (Derived_Type, RM_Size (Parent_Type)); |
| Set_Depends_On_Private (Derived_Type, |
| Has_Private_Component (Derived_Type)); |
| Conditional_Delay (Derived_Type, Subt); |
| |
| -- Ada 2005 (AI-231). Set the null-exclusion attribute |
| |
| if Null_Exclusion_Present (Type_Definition (N)) |
| or else Can_Never_Be_Null (Parent_Type) |
| then |
| Set_Can_Never_Be_Null (Derived_Type); |
| end if; |
| |
| -- Note: we do not copy the Storage_Size_Variable, since |
| -- we always go to the root type for this information. |
| |
| -- Apply range checks to discriminants for derived record case |
| -- ??? THIS CODE SHOULD NOT BE HERE REALLY. |
| |
| Desig_Type := Designated_Type (Derived_Type); |
| if Is_Composite_Type (Desig_Type) |
| and then (not Is_Array_Type (Desig_Type)) |
| and then Has_Discriminants (Desig_Type) |
| and then Base_Type (Desig_Type) /= Desig_Type |
| then |
| Discr_Con_Elist := Discriminant_Constraint (Desig_Type); |
| Discr_Con_El := First_Elmt (Discr_Con_Elist); |
| |
| Discr := First_Discriminant (Base_Type (Desig_Type)); |
| while Present (Discr_Con_El) loop |
| Apply_Range_Check (Node (Discr_Con_El), Etype (Discr)); |
| Next_Elmt (Discr_Con_El); |
| Next_Discriminant (Discr); |
| end loop; |
| end if; |
| end Build_Derived_Access_Type; |
| |
| ------------------------------ |
| -- Build_Derived_Array_Type -- |
| ------------------------------ |
| |
| procedure Build_Derived_Array_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| Tdef : constant Node_Id := Type_Definition (N); |
| Indic : constant Node_Id := Subtype_Indication (Tdef); |
| Parent_Base : constant Entity_Id := Base_Type (Parent_Type); |
| Implicit_Base : Entity_Id; |
| New_Indic : Node_Id; |
| |
| procedure Make_Implicit_Base; |
| -- If the parent subtype is constrained, the derived type is a |
| -- subtype of an implicit base type derived from the parent base. |
| |
| ------------------------ |
| -- Make_Implicit_Base -- |
| ------------------------ |
| |
| procedure Make_Implicit_Base is |
| begin |
| Implicit_Base := |
| Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B'); |
| |
| Set_Ekind (Implicit_Base, Ekind (Parent_Base)); |
| Set_Etype (Implicit_Base, Parent_Base); |
| |
| Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base); |
| Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base); |
| |
| Set_Has_Delayed_Freeze (Implicit_Base, True); |
| end Make_Implicit_Base; |
| |
| -- Start of processing for Build_Derived_Array_Type |
| |
| begin |
| if not Is_Constrained (Parent_Type) then |
| if Nkind (Indic) /= N_Subtype_Indication then |
| Set_Ekind (Derived_Type, E_Array_Type); |
| |
| Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type); |
| Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type); |
| |
| Set_Has_Delayed_Freeze (Derived_Type, True); |
| |
| else |
| Make_Implicit_Base; |
| Set_Etype (Derived_Type, Implicit_Base); |
| |
| New_Indic := |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Derived_Type, |
| Subtype_Indication => |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Reference_To (Implicit_Base, Loc), |
| Constraint => Constraint (Indic))); |
| |
| Rewrite (N, New_Indic); |
| Analyze (N); |
| end if; |
| |
| else |
| if Nkind (Indic) /= N_Subtype_Indication then |
| Make_Implicit_Base; |
| |
| Set_Ekind (Derived_Type, Ekind (Parent_Type)); |
| Set_Etype (Derived_Type, Implicit_Base); |
| Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type); |
| |
| else |
| Error_Msg_N ("illegal constraint on constrained type", Indic); |
| end if; |
| end if; |
| |
| -- If parent type is not a derived type itself, and is declared in |
| -- closed scope (e.g. a subprogram), then we must explicitly introduce |
| -- the new type's concatenation operator since Derive_Subprograms |
| -- will not inherit the parent's operator. If the parent type is |
| -- unconstrained, the operator is of the unconstrained base type. |
| |
| if Number_Dimensions (Parent_Type) = 1 |
| and then not Is_Limited_Type (Parent_Type) |
| and then not Is_Derived_Type (Parent_Type) |
| and then not Is_Package_Or_Generic_Package |
| (Scope (Base_Type (Parent_Type))) |
| then |
| if not Is_Constrained (Parent_Type) |
| and then Is_Constrained (Derived_Type) |
| then |
| New_Concatenation_Op (Implicit_Base); |
| else |
| New_Concatenation_Op (Derived_Type); |
| end if; |
| end if; |
| end Build_Derived_Array_Type; |
| |
| ----------------------------------- |
| -- Build_Derived_Concurrent_Type -- |
| ----------------------------------- |
| |
| procedure Build_Derived_Concurrent_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id) |
| is |
| D_Constraint : Node_Id; |
| Disc_Spec : Node_Id; |
| Old_Disc : Entity_Id; |
| New_Disc : Entity_Id; |
| |
| Constraint_Present : constant Boolean := |
| Nkind (Subtype_Indication (Type_Definition (N))) |
| = N_Subtype_Indication; |
| |
| begin |
| Set_Stored_Constraint (Derived_Type, No_Elist); |
| |
| if Is_Task_Type (Parent_Type) then |
| Set_Storage_Size_Variable (Derived_Type, |
| Storage_Size_Variable (Parent_Type)); |
| end if; |
| |
| if Present (Discriminant_Specifications (N)) then |
| New_Scope (Derived_Type); |
| Check_Or_Process_Discriminants (N, Derived_Type); |
| End_Scope; |
| |
| elsif Constraint_Present then |
| |
| -- Build constrained subtype and derive from it |
| |
| declare |
| Loc : constant Source_Ptr := Sloc (N); |
| Anon : constant Entity_Id := |
| Make_Defining_Identifier (Loc, |
| New_External_Name (Chars (Derived_Type), 'T')); |
| Decl : Node_Id; |
| |
| begin |
| Decl := |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Anon, |
| Subtype_Indication => |
| New_Copy_Tree (Subtype_Indication (Type_Definition (N)))); |
| Insert_Before (N, Decl); |
| Rewrite (Subtype_Indication (Type_Definition (N)), |
| New_Occurrence_Of (Anon, Loc)); |
| Analyze (Decl); |
| Set_Analyzed (Derived_Type, False); |
| Analyze (N); |
| return; |
| end; |
| end if; |
| |
| -- All attributes are inherited from parent. In particular, |
| -- entries and the corresponding record type are the same. |
| -- Discriminants may be renamed, and must be treated separately. |
| |
| Set_Has_Discriminants |
| (Derived_Type, Has_Discriminants (Parent_Type)); |
| Set_Corresponding_Record_Type |
| (Derived_Type, Corresponding_Record_Type (Parent_Type)); |
| |
| if Constraint_Present then |
| if not Has_Discriminants (Parent_Type) then |
| Error_Msg_N ("untagged parent must have discriminants", N); |
| |
| elsif Present (Discriminant_Specifications (N)) then |
| |
| -- Verify that new discriminants are used to constrain old ones |
| |
| D_Constraint := |
| First |
| (Constraints |
| (Constraint (Subtype_Indication (Type_Definition (N))))); |
| |
| Old_Disc := First_Discriminant (Parent_Type); |
| New_Disc := First_Discriminant (Derived_Type); |
| Disc_Spec := First (Discriminant_Specifications (N)); |
| while Present (Old_Disc) and then Present (Disc_Spec) loop |
| if Nkind (Discriminant_Type (Disc_Spec)) /= |
| N_Access_Definition |
| then |
| Analyze (Discriminant_Type (Disc_Spec)); |
| |
| if not Subtypes_Statically_Compatible ( |
| Etype (Discriminant_Type (Disc_Spec)), |
| Etype (Old_Disc)) |
| then |
| Error_Msg_N |
| ("not statically compatible with parent discriminant", |
| Discriminant_Type (Disc_Spec)); |
| end if; |
| end if; |
| |
| if Nkind (D_Constraint) = N_Identifier |
| and then Chars (D_Constraint) /= |
| Chars (Defining_Identifier (Disc_Spec)) |
| then |
| Error_Msg_N ("new discriminants must constrain old ones", |
| D_Constraint); |
| else |
| Set_Corresponding_Discriminant (New_Disc, Old_Disc); |
| end if; |
| |
| Next_Discriminant (Old_Disc); |
| Next_Discriminant (New_Disc); |
| Next (Disc_Spec); |
| end loop; |
| |
| if Present (Old_Disc) or else Present (Disc_Spec) then |
| Error_Msg_N ("discriminant mismatch in derivation", N); |
| end if; |
| |
| end if; |
| |
| elsif Present (Discriminant_Specifications (N)) then |
| Error_Msg_N |
| ("missing discriminant constraint in untagged derivation", |
| N); |
| end if; |
| |
| if Present (Discriminant_Specifications (N)) then |
| Old_Disc := First_Discriminant (Parent_Type); |
| while Present (Old_Disc) loop |
| |
| if No (Next_Entity (Old_Disc)) |
| or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant |
| then |
| Set_Next_Entity (Last_Entity (Derived_Type), |
| Next_Entity (Old_Disc)); |
| exit; |
| end if; |
| |
| Next_Discriminant (Old_Disc); |
| end loop; |
| |
| else |
| Set_First_Entity (Derived_Type, First_Entity (Parent_Type)); |
| if Has_Discriminants (Parent_Type) then |
| Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type)); |
| Set_Discriminant_Constraint ( |
| Derived_Type, Discriminant_Constraint (Parent_Type)); |
| end if; |
| end if; |
| |
| Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type)); |
| |
| Set_Has_Completion (Derived_Type); |
| end Build_Derived_Concurrent_Type; |
| |
| ------------------------------------ |
| -- Build_Derived_Enumeration_Type -- |
| ------------------------------------ |
| |
| procedure Build_Derived_Enumeration_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| Def : constant Node_Id := Type_Definition (N); |
| Indic : constant Node_Id := Subtype_Indication (Def); |
| Implicit_Base : Entity_Id; |
| Literal : Entity_Id; |
| New_Lit : Entity_Id; |
| Literals_List : List_Id; |
| Type_Decl : Node_Id; |
| Hi, Lo : Node_Id; |
| Rang_Expr : Node_Id; |
| |
| begin |
| -- Since types Standard.Character and Standard.Wide_Character do |
| -- not have explicit literals lists we need to process types derived |
| -- from them specially. This is handled by Derived_Standard_Character. |
| -- If the parent type is a generic type, there are no literals either, |
| -- and we construct the same skeletal representation as for the generic |
| -- parent type. |
| |
| if Root_Type (Parent_Type) = Standard_Character |
| or else Root_Type (Parent_Type) = Standard_Wide_Character |
| or else Root_Type (Parent_Type) = Standard_Wide_Wide_Character |
| then |
| Derived_Standard_Character (N, Parent_Type, Derived_Type); |
| |
| elsif Is_Generic_Type (Root_Type (Parent_Type)) then |
| declare |
| Lo : Node_Id; |
| Hi : Node_Id; |
| |
| begin |
| Lo := |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_First, |
| Prefix => New_Reference_To (Derived_Type, Loc)); |
| Set_Etype (Lo, Derived_Type); |
| |
| Hi := |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Last, |
| Prefix => New_Reference_To (Derived_Type, Loc)); |
| Set_Etype (Hi, Derived_Type); |
| |
| Set_Scalar_Range (Derived_Type, |
| Make_Range (Loc, |
| Low_Bound => Lo, |
| High_Bound => Hi)); |
| end; |
| |
| else |
| -- If a constraint is present, analyze the bounds to catch |
| -- premature usage of the derived literals. |
| |
| if Nkind (Indic) = N_Subtype_Indication |
| and then Nkind (Range_Expression (Constraint (Indic))) = N_Range |
| then |
| Analyze (Low_Bound (Range_Expression (Constraint (Indic)))); |
| Analyze (High_Bound (Range_Expression (Constraint (Indic)))); |
| end if; |
| |
| -- Introduce an implicit base type for the derived type even |
| -- if there is no constraint attached to it, since this seems |
| -- closer to the Ada semantics. Build a full type declaration |
| -- tree for the derived type using the implicit base type as |
| -- the defining identifier. The build a subtype declaration |
| -- tree which applies the constraint (if any) have it replace |
| -- the derived type declaration. |
| |
| Literal := First_Literal (Parent_Type); |
| Literals_List := New_List; |
| while Present (Literal) |
| and then Ekind (Literal) = E_Enumeration_Literal |
| loop |
| -- Literals of the derived type have the same representation as |
| -- those of the parent type, but this representation can be |
| -- overridden by an explicit representation clause. Indicate |
| -- that there is no explicit representation given yet. These |
| -- derived literals are implicit operations of the new type, |
| -- and can be overridden by explicit ones. |
| |
| if Nkind (Literal) = N_Defining_Character_Literal then |
| New_Lit := |
| Make_Defining_Character_Literal (Loc, Chars (Literal)); |
| else |
| New_Lit := Make_Defining_Identifier (Loc, Chars (Literal)); |
| end if; |
| |
| Set_Ekind (New_Lit, E_Enumeration_Literal); |
| Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal)); |
| Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal)); |
| Set_Enumeration_Rep_Expr (New_Lit, Empty); |
| Set_Alias (New_Lit, Literal); |
| Set_Is_Known_Valid (New_Lit, True); |
| |
| Append (New_Lit, Literals_List); |
| Next_Literal (Literal); |
| end loop; |
| |
| Implicit_Base := |
| Make_Defining_Identifier (Sloc (Derived_Type), |
| New_External_Name (Chars (Derived_Type), 'B')); |
| |
| -- Indicate the proper nature of the derived type. This must |
| -- be done before analysis of the literals, to recognize cases |
| -- when a literal may be hidden by a previous explicit function |
| -- definition (cf. c83031a). |
| |
| Set_Ekind (Derived_Type, E_Enumeration_Subtype); |
| Set_Etype (Derived_Type, Implicit_Base); |
| |
| Type_Decl := |
| Make_Full_Type_Declaration (Loc, |
| Defining_Identifier => Implicit_Base, |
| Discriminant_Specifications => No_List, |
| Type_Definition => |
| Make_Enumeration_Type_Definition (Loc, Literals_List)); |
| |
| Mark_Rewrite_Insertion (Type_Decl); |
| Insert_Before (N, Type_Decl); |
| Analyze (Type_Decl); |
| |
| -- After the implicit base is analyzed its Etype needs to be changed |
| -- to reflect the fact that it is derived from the parent type which |
| -- was ignored during analysis. We also set the size at this point. |
| |
| Set_Etype (Implicit_Base, Parent_Type); |
| |
| Set_Size_Info (Implicit_Base, Parent_Type); |
| Set_RM_Size (Implicit_Base, RM_Size (Parent_Type)); |
| Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type)); |
| |
| Set_Has_Non_Standard_Rep |
| (Implicit_Base, Has_Non_Standard_Rep |
| (Parent_Type)); |
| Set_Has_Delayed_Freeze (Implicit_Base); |
| |
| -- Process the subtype indication including a validation check |
| -- on the constraint, if any. If a constraint is given, its bounds |
| -- must be implicitly converted to the new type. |
| |
| if Nkind (Indic) = N_Subtype_Indication then |
| declare |
| R : constant Node_Id := |
| Range_Expression (Constraint (Indic)); |
| |
| begin |
| if Nkind (R) = N_Range then |
| Hi := Build_Scalar_Bound |
| (High_Bound (R), Parent_Type, Implicit_Base); |
| Lo := Build_Scalar_Bound |
| (Low_Bound (R), Parent_Type, Implicit_Base); |
| |
| else |
| -- Constraint is a Range attribute. Replace with the |
| -- explicit mention of the bounds of the prefix, which must |
| -- be a subtype. |
| |
| Analyze (Prefix (R)); |
| Hi := |
| Convert_To (Implicit_Base, |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Last, |
| Prefix => |
| New_Occurrence_Of (Entity (Prefix (R)), Loc))); |
| |
| Lo := |
| Convert_To (Implicit_Base, |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_First, |
| Prefix => |
| New_Occurrence_Of (Entity (Prefix (R)), Loc))); |
| end if; |
| end; |
| |
| else |
| Hi := |
| Build_Scalar_Bound |
| (Type_High_Bound (Parent_Type), |
| Parent_Type, Implicit_Base); |
| Lo := |
| Build_Scalar_Bound |
| (Type_Low_Bound (Parent_Type), |
| Parent_Type, Implicit_Base); |
| end if; |
| |
| Rang_Expr := |
| Make_Range (Loc, |
| Low_Bound => Lo, |
| High_Bound => Hi); |
| |
| -- If we constructed a default range for the case where no range |
| -- was given, then the expressions in the range must not freeze |
| -- since they do not correspond to expressions in the source. |
| |
| if Nkind (Indic) /= N_Subtype_Indication then |
| Set_Must_Not_Freeze (Lo); |
| Set_Must_Not_Freeze (Hi); |
| Set_Must_Not_Freeze (Rang_Expr); |
| end if; |
| |
| Rewrite (N, |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Derived_Type, |
| Subtype_Indication => |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc), |
| Constraint => |
| Make_Range_Constraint (Loc, |
| Range_Expression => Rang_Expr)))); |
| |
| Analyze (N); |
| |
| -- If pragma Discard_Names applies on the first subtype of the |
| -- parent type, then it must be applied on this subtype as well. |
| |
| if Einfo.Discard_Names (First_Subtype (Parent_Type)) then |
| Set_Discard_Names (Derived_Type); |
| end if; |
| |
| -- Apply a range check. Since this range expression doesn't have an |
| -- Etype, we have to specifically pass the Source_Typ parameter. Is |
| -- this right??? |
| |
| if Nkind (Indic) = N_Subtype_Indication then |
| Apply_Range_Check (Range_Expression (Constraint (Indic)), |
| Parent_Type, |
| Source_Typ => Entity (Subtype_Mark (Indic))); |
| end if; |
| end if; |
| end Build_Derived_Enumeration_Type; |
| |
| -------------------------------- |
| -- Build_Derived_Numeric_Type -- |
| -------------------------------- |
| |
| procedure Build_Derived_Numeric_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| Tdef : constant Node_Id := Type_Definition (N); |
| Indic : constant Node_Id := Subtype_Indication (Tdef); |
| Parent_Base : constant Entity_Id := Base_Type (Parent_Type); |
| No_Constraint : constant Boolean := Nkind (Indic) /= |
| N_Subtype_Indication; |
| Implicit_Base : Entity_Id; |
| |
| Lo : Node_Id; |
| Hi : Node_Id; |
| |
| begin |
| -- Process the subtype indication including a validation check on |
| -- the constraint if any. |
| |
| Discard_Node (Process_Subtype (Indic, N)); |
| |
| -- Introduce an implicit base type for the derived type even if there |
| -- is no constraint attached to it, since this seems closer to the Ada |
| -- semantics. |
| |
| Implicit_Base := |
| Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B'); |
| |
| Set_Etype (Implicit_Base, Parent_Base); |
| Set_Ekind (Implicit_Base, Ekind (Parent_Base)); |
| Set_Size_Info (Implicit_Base, Parent_Base); |
| Set_RM_Size (Implicit_Base, RM_Size (Parent_Base)); |
| Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base)); |
| Set_Parent (Implicit_Base, Parent (Derived_Type)); |
| |
| if Is_Discrete_Or_Fixed_Point_Type (Parent_Base) then |
| Set_RM_Size (Implicit_Base, RM_Size (Parent_Base)); |
| end if; |
| |
| Set_Has_Delayed_Freeze (Implicit_Base); |
| |
| Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base)); |
| Hi := New_Copy_Tree (Type_High_Bound (Parent_Base)); |
| |
| Set_Scalar_Range (Implicit_Base, |
| Make_Range (Loc, |
| Low_Bound => Lo, |
| High_Bound => Hi)); |
| |
| if Has_Infinities (Parent_Base) then |
| Set_Includes_Infinities (Scalar_Range (Implicit_Base)); |
| end if; |
| |
| -- The Derived_Type, which is the entity of the declaration, is a |
| -- subtype of the implicit base. Its Ekind is a subtype, even in the |
| -- absence of an explicit constraint. |
| |
| Set_Etype (Derived_Type, Implicit_Base); |
| |
| -- If we did not have a constraint, then the Ekind is set from the |
| -- parent type (otherwise Process_Subtype has set the bounds) |
| |
| if No_Constraint then |
| Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type))); |
| end if; |
| |
| -- If we did not have a range constraint, then set the range from the |
| -- parent type. Otherwise, the call to Process_Subtype has set the |
| -- bounds. |
| |
| if No_Constraint |
| or else not Has_Range_Constraint (Indic) |
| then |
| Set_Scalar_Range (Derived_Type, |
| Make_Range (Loc, |
| Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)), |
| High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type)))); |
| Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type)); |
| |
| if Has_Infinities (Parent_Type) then |
| Set_Includes_Infinities (Scalar_Range (Derived_Type)); |
| end if; |
| end if; |
| |
| -- Set remaining type-specific fields, depending on numeric type |
| |
| if Is_Modular_Integer_Type (Parent_Type) then |
| Set_Modulus (Implicit_Base, Modulus (Parent_Base)); |
| |
| Set_Non_Binary_Modulus |
| (Implicit_Base, Non_Binary_Modulus (Parent_Base)); |
| |
| elsif Is_Floating_Point_Type (Parent_Type) then |
| |
| -- Digits of base type is always copied from the digits value of |
| -- the parent base type, but the digits of the derived type will |
| -- already have been set if there was a constraint present. |
| |
| Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base)); |
| Set_Vax_Float (Implicit_Base, Vax_Float (Parent_Base)); |
| |
| if No_Constraint then |
| Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type)); |
| end if; |
| |
| elsif Is_Fixed_Point_Type (Parent_Type) then |
| |
| -- Small of base type and derived type are always copied from the |
| -- parent base type, since smalls never change. The delta of the |
| -- base type is also copied from the parent base type. However the |
| -- delta of the derived type will have been set already if a |
| -- constraint was present. |
| |
| Set_Small_Value (Derived_Type, Small_Value (Parent_Base)); |
| Set_Small_Value (Implicit_Base, Small_Value (Parent_Base)); |
| Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base)); |
| |
| if No_Constraint then |
| Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type)); |
| end if; |
| |
| -- The scale and machine radix in the decimal case are always |
| -- copied from the parent base type. |
| |
| if Is_Decimal_Fixed_Point_Type (Parent_Type) then |
| Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base)); |
| Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base)); |
| |
| Set_Machine_Radix_10 |
| (Derived_Type, Machine_Radix_10 (Parent_Base)); |
| Set_Machine_Radix_10 |
| (Implicit_Base, Machine_Radix_10 (Parent_Base)); |
| |
| Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base)); |
| |
| if No_Constraint then |
| Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base)); |
| |
| else |
| -- the analysis of the subtype_indication sets the |
| -- digits value of the derived type. |
| |
| null; |
| end if; |
| end if; |
| end if; |
| |
| -- The type of the bounds is that of the parent type, and they |
| -- must be converted to the derived type. |
| |
| Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc); |
| |
| -- The implicit_base should be frozen when the derived type is frozen, |
| -- but note that it is used in the conversions of the bounds. For fixed |
| -- types we delay the determination of the bounds until the proper |
| -- freezing point. For other numeric types this is rejected by GCC, for |
| -- reasons that are currently unclear (???), so we choose to freeze the |
| -- implicit base now. In the case of integers and floating point types |
| -- this is harmless because subsequent representation clauses cannot |
| -- affect anything, but it is still baffling that we cannot use the |
| -- same mechanism for all derived numeric types. |
| |
| if Is_Fixed_Point_Type (Parent_Type) then |
| Conditional_Delay (Implicit_Base, Parent_Type); |
| else |
| Freeze_Before (N, Implicit_Base); |
| end if; |
| end Build_Derived_Numeric_Type; |
| |
| -------------------------------- |
| -- Build_Derived_Private_Type -- |
| -------------------------------- |
| |
| procedure Build_Derived_Private_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id; |
| Is_Completion : Boolean; |
| Derive_Subps : Boolean := True) |
| is |
| Der_Base : Entity_Id; |
| Discr : Entity_Id; |
| Full_Decl : Node_Id := Empty; |
| Full_Der : Entity_Id; |
| Full_P : Entity_Id; |
| Last_Discr : Entity_Id; |
| Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type)); |
| Swapped : Boolean := False; |
| |
| procedure Copy_And_Build; |
| -- Copy derived type declaration, replace parent with its full view, |
| -- and analyze new declaration. |
| |
| -------------------- |
| -- Copy_And_Build -- |
| -------------------- |
| |
| procedure Copy_And_Build is |
| Full_N : Node_Id; |
| |
| begin |
| if Ekind (Parent_Type) in Record_Kind |
| or else |
| (Ekind (Parent_Type) in Enumeration_Kind |
| and then Root_Type (Parent_Type) /= Standard_Character |
| and then Root_Type (Parent_Type) /= Standard_Wide_Character |
| and then Root_Type (Parent_Type) /= Standard_Wide_Wide_Character |
| and then not Is_Generic_Type (Root_Type (Parent_Type))) |
| then |
| Full_N := New_Copy_Tree (N); |
| Insert_After (N, Full_N); |
| Build_Derived_Type ( |
| Full_N, Parent_Type, Full_Der, True, Derive_Subps => False); |
| |
| else |
| Build_Derived_Type ( |
| N, Parent_Type, Full_Der, True, Derive_Subps => False); |
| end if; |
| end Copy_And_Build; |
| |
| -- Start of processing for Build_Derived_Private_Type |
| |
| begin |
| if Is_Tagged_Type (Parent_Type) then |
| Build_Derived_Record_Type |
| (N, Parent_Type, Derived_Type, Derive_Subps); |
| return; |
| |
| elsif Has_Discriminants (Parent_Type) then |
| if Present (Full_View (Parent_Type)) then |
| if not Is_Completion then |
| |
| -- Copy declaration for subsequent analysis, to provide a |
| -- completion for what is a private declaration. Indicate that |
| -- the full type is internally generated. |
| |
| Full_Decl := New_Copy_Tree (N); |
| Full_Der := New_Copy (Derived_Type); |
| Set_Comes_From_Source (Full_Decl, False); |
| Set_Comes_From_Source (Full_Der, False); |
| |
| Insert_After (N, Full_Decl); |
| |
| else |
| -- If this is a completion, the full view being built is |
| -- itself private. We build a subtype of the parent with |
| -- the same constraints as this full view, to convey to the |
| -- back end the constrained components and the size of this |
| -- subtype. If the parent is constrained, its full view can |
| -- serve as the underlying full view of the derived type. |
| |
| if No (Discriminant_Specifications (N)) then |
| if Nkind (Subtype_Indication (Type_Definition (N))) = |
| N_Subtype_Indication |
| then |
| Build_Underlying_Full_View (N, Derived_Type, Parent_Type); |
| |
| elsif Is_Constrained (Full_View (Parent_Type)) then |
| Set_Underlying_Full_View (Derived_Type, |
| Full_View (Parent_Type)); |
| end if; |
| |
| else |
| -- If there are new discriminants, the parent subtype is |
| -- constrained by them, but it is not clear how to build |
| -- the underlying_full_view in this case ??? |
| |
| null; |
| end if; |
| end if; |
| end if; |
| |
| -- Build partial view of derived type from partial view of parent |
| |
| Build_Derived_Record_Type |
| (N, Parent_Type, Derived_Type, Derive_Subps); |
| |
| if Present (Full_View (Parent_Type)) |
| and then not Is_Completion |
| then |
| if not In_Open_Scopes (Par_Scope) |
| or else not In_Same_Source_Unit (N, Parent_Type) |
| then |
| -- Swap partial and full views temporarily |
| |
| Install_Private_Declarations (Par_Scope); |
| Install_Visible_Declarations (Par_Scope); |
| Swapped := True; |
| end if; |
| |
| -- Build full view of derived type from full view of parent which |
| -- is now installed. Subprograms have been derived on the partial |
| -- view, the completion does not derive them anew. |
| |
| if not Is_Tagged_Type (Parent_Type) then |
| |
| -- If the parent is itself derived from another private type, |
| -- installing the private declarations has not affected its |
| -- privacy status, so use its own full view explicitly. |
| |
| if Is_Private_Type (Parent_Type) then |
| Build_Derived_Record_Type |
| (Full_Decl, Full_View (Parent_Type), Full_Der, False); |
| else |
| Build_Derived_Record_Type |
| (Full_Decl, Parent_Type, Full_Der, False); |
| end if; |
| |
| else |
| -- If full view of parent is tagged, the completion |
| -- inherits the proper primitive operations. |
| |
| Set_Defining_Identifier (Full_Decl, Full_Der); |
| Build_Derived_Record_Type |
| (Full_Decl, Parent_Type, Full_Der, Derive_Subps); |
| Set_Analyzed (Full_Decl); |
| end if; |
| |
| if Swapped then |
| Uninstall_Declarations (Par_Scope); |
| |
| if In_Open_Scopes (Par_Scope) then |
| Install_Visible_Declarations (Par_Scope); |
| end if; |
| end if; |
| |
| Der_Base := Base_Type (Derived_Type); |
| Set_Full_View (Derived_Type, Full_Der); |
| Set_Full_View (Der_Base, Base_Type (Full_Der)); |
| |
| -- Copy the discriminant list from full view to the partial views |
| -- (base type and its subtype). Gigi requires that the partial |
| -- and full views have the same discriminants. |
| |
| -- Note that since the partial view is pointing to discriminants |
| -- in the full view, their scope will be that of the full view. |
| -- This might cause some front end problems and need |
| -- adjustment??? |
| |
| Discr := First_Discriminant (Base_Type (Full_Der)); |
| Set_First_Entity (Der_Base, Discr); |
| |
| loop |
| Last_Discr := Discr; |
| Next_Discriminant (Discr); |
| exit when No (Discr); |
| end loop; |
| |
| Set_Last_Entity (Der_Base, Last_Discr); |
| |
| Set_First_Entity (Derived_Type, First_Entity (Der_Base)); |
| Set_Last_Entity (Derived_Type, Last_Entity (Der_Base)); |
| Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type)); |
| |
| else |
| -- If this is a completion, the derived type stays private |
| -- and there is no need to create a further full view, except |
| -- in the unusual case when the derivation is nested within a |
| -- child unit, see below. |
| |
| null; |
| end if; |
| |
| elsif Present (Full_View (Parent_Type)) |
| and then Has_Discriminants (Full_View (Parent_Type)) |
| then |
| if Has_Unknown_Discriminants (Parent_Type) |
| and then Nkind (Subtype_Indication (Type_Definition (N))) |
| = N_Subtype_Indication |
| then |
| Error_Msg_N |
| ("cannot constrain type with unknown discriminants", |
| Subtype_Indication (Type_Definition (N))); |
| return; |
| end if; |
| |
| -- If full view of parent is a record type, Build full view as |
| -- a derivation from the parent's full view. Partial view remains |
| -- private. For code generation and linking, the full view must |
| -- have the same public status as the partial one. This full view |
| -- is only needed if the parent type is in an enclosing scope, so |
| -- that the full view may actually become visible, e.g. in a child |
| -- unit. This is both more efficient, and avoids order of freezing |
| -- problems with the added entities. |
| |
| if not Is_Private_Type (Full_View (Parent_Type)) |
| and then (In_Open_Scopes (Scope (Parent_Type))) |
| then |
| Full_Der := Make_Defining_Identifier (Sloc (Derived_Type), |
| Chars (Derived_Type)); |
| Set_Is_Itype (Full_Der); |
| Set_Has_Private_Declaration (Full_Der); |
| Set_Has_Private_Declaration (Derived_Type); |
| Set_Associated_Node_For_Itype (Full_Der, N); |
| Set_Parent (Full_Der, Parent (Derived_Type)); |
| Set_Full_View (Derived_Type, Full_Der); |
| Set_Is_Public (Full_Der, Is_Public (Derived_Type)); |
| Full_P := Full_View (Parent_Type); |
| Exchange_Declarations (Parent_Type); |
| Copy_And_Build; |
| Exchange_Declarations (Full_P); |
| |
| else |
| Build_Derived_Record_Type |
| (N, Full_View (Parent_Type), Derived_Type, |
| Derive_Subps => False); |
| end if; |
| |
| -- In any case, the primitive operations are inherited from |
| -- the parent type, not from the internal full view. |
| |
| Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type)); |
| |
| if Derive_Subps then |
| Derive_Subprograms (Parent_Type, Derived_Type); |
| end if; |
| |
| else |
| -- Untagged type, No discriminants on either view |
| |
| if Nkind (Subtype_Indication (Type_Definition (N))) = |
| N_Subtype_Indication |
| then |
| Error_Msg_N |
| ("illegal constraint on type without discriminants", N); |
| end if; |
| |
| if Present (Discriminant_Specifications (N)) |
| and then Present (Full_View (Parent_Type)) |
| and then not Is_Tagged_Type (Full_View (Parent_Type)) |
| then |
| Error_Msg_N |
| ("cannot add discriminants to untagged type", N); |
| end if; |
| |
| Set_Stored_Constraint (Derived_Type, No_Elist); |
| Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type)); |
| Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type)); |
| Set_Has_Controlled_Component |
| (Derived_Type, Has_Controlled_Component |
| (Parent_Type)); |
| |
| -- Direct controlled types do not inherit Finalize_Storage_Only flag |
| |
| if not Is_Controlled (Parent_Type) then |
| Set_Finalize_Storage_Only |
| (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type)); |
| end if; |
| |
| -- Construct the implicit full view by deriving from full view of |
| -- the parent type. In order to get proper visibility, we install |
| -- the parent scope and its declarations. |
| |
| -- ??? if the parent is untagged private and its completion is |
| -- tagged, this mechanism will not work because we cannot derive |
| -- from the tagged full view unless we have an extension |
| |
| if Present (Full_View (Parent_Type)) |
| and then not Is_Tagged_Type (Full_View (Parent_Type)) |
| and then not Is_Completion |
| then |
| Full_Der := |
| Make_Defining_Identifier (Sloc (Derived_Type), |
| Chars => Chars (Derived_Type)); |
| Set_Is_Itype (Full_Der); |
| Set_Has_Private_Declaration (Full_Der); |
| Set_Has_Private_Declaration (Derived_Type); |
| Set_Associated_Node_For_Itype (Full_Der, N); |
| Set_Parent (Full_Der, Parent (Derived_Type)); |
| Set_Full_View (Derived_Type, Full_Der); |
| |
| if not In_Open_Scopes (Par_Scope) then |
| Install_Private_Declarations (Par_Scope); |
| Install_Visible_Declarations (Par_Scope); |
| Copy_And_Build; |
| Uninstall_Declarations (Par_Scope); |
| |
| -- If parent scope is open and in another unit, and parent has a |
| -- completion, then the derivation is taking place in the visible |
| -- part of a child unit. In that case retrieve the full view of |
| -- the parent momentarily. |
| |
| elsif not In_Same_Source_Unit (N, Parent_Type) then |
| Full_P := Full_View (Parent_Type); |
| Exchange_Declarations (Parent_Type); |
| Copy_And_Build; |
| Exchange_Declarations (Full_P); |
| |
| -- Otherwise it is a local derivation |
| |
| else |
| Copy_And_Build; |
| end if; |
| |
| Set_Scope (Full_Der, Current_Scope); |
| Set_Is_First_Subtype (Full_Der, |
| Is_First_Subtype (Derived_Type)); |
| Set_Has_Size_Clause (Full_Der, False); |
| Set_Has_Alignment_Clause (Full_Der, False); |
| Set_Next_Entity (Full_Der, Empty); |
| Set_Has_Delayed_Freeze (Full_Der); |
| Set_Is_Frozen (Full_Der, False); |
| Set_Freeze_Node (Full_Der, Empty); |
| Set_Depends_On_Private (Full_Der, |
| Has_Private_Component (Full_Der)); |
| Set_Public_Status (Full_Der); |
| end if; |
| end if; |
| |
| Set_Has_Unknown_Discriminants (Derived_Type, |
| Has_Unknown_Discriminants (Parent_Type)); |
| |
| if Is_Private_Type (Derived_Type) then |
| Set_Private_Dependents (Derived_Type, New_Elmt_List); |
| end if; |
| |
| if Is_Private_Type (Parent_Type) |
| and then Base_Type (Parent_Type) = Parent_Type |
| and then In_Open_Scopes (Scope (Parent_Type)) |
| then |
| Append_Elmt (Derived_Type, Private_Dependents (Parent_Type)); |
| |
| if Is_Child_Unit (Scope (Current_Scope)) |
| and then Is_Completion |
| and then In_Private_Part (Current_Scope) |
| and then Scope (Parent_Type) /= Current_Scope |
| then |
| -- This is the unusual case where a type completed by a private |
| -- derivation occurs within a package nested in a child unit, |
| -- and the parent is declared in an ancestor. In this case, the |
| -- full view of the parent type will become visible in the body |
| -- of the enclosing child, and only then will the current type |
| -- be possibly non-private. We build a underlying full view that |
| -- will be installed when the enclosing child body is compiled. |
| |
| declare |
| IR : constant Node_Id := Make_Itype_Reference (Sloc (N)); |
| |
| begin |
| Full_Der := |
| Make_Defining_Identifier (Sloc (Derived_Type), |
| Chars (Derived_Type)); |
| Set_Is_Itype (Full_Der); |
| Set_Itype (IR, Full_Der); |
| Insert_After (N, IR); |
| |
| -- The full view will be used to swap entities on entry/exit |
| -- to the body, and must appear in the entity list for the |
| -- package. |
| |
| Append_Entity (Full_Der, Scope (Derived_Type)); |
| Set_Has_Private_Declaration (Full_Der); |
| Set_Has_Private_Declaration (Derived_Type); |
| Set_Associated_Node_For_Itype (Full_Der, N); |
| Set_Parent (Full_Der, Parent (Derived_Type)); |
| Full_P := Full_View (Parent_Type); |
| Exchange_Declarations (Parent_Type); |
| Copy_And_Build; |
| Exchange_Declarations (Full_P); |
| Set_Underlying_Full_View (Derived_Type, Full_Der); |
| end; |
| end if; |
| end if; |
| end Build_Derived_Private_Type; |
| |
| ------------------------------- |
| -- Build_Derived_Record_Type -- |
| ------------------------------- |
| |
| -- 1. INTRODUCTION |
| |
| -- Ideally we would like to use the same model of type derivation for |
| -- tagged and untagged record types. Unfortunately this is not quite |
| -- possible because the semantics of representation clauses is different |
| -- for tagged and untagged records under inheritance. Consider the |
| -- following: |
| |
| -- type R (...) is [tagged] record ... end record; |
| -- type T (...) is new R (...) [with ...]; |
| |
| -- The representation clauses of T can specify a completely different |
| -- record layout from R's. Hence the same component can be placed in |
| -- two very different positions in objects of type T and R. If R and T |
| -- are tagged types, representation clauses for T can only specify the |
| -- layout of non inherited components, thus components that are common |
| -- in R and T have the same position in objects of type R and T. |
| |
| -- This has two implications. The first is that the entire tree for R's |
| -- declaration needs to be copied for T in the untagged case, so that T |
| -- can be viewed as a record type of its own with its own representation |
| -- clauses. The second implication is the way we handle discriminants. |
| -- Specifically, in the untagged case we need a way to communicate to Gigi |
| -- what are the real discriminants in the record, while for the semantics |
| -- we need to consider those introduced by the user to rename the |
| -- discriminants in the parent type. This is handled by introducing the |
| -- notion of stored discriminants. See below for more. |
| |
| -- Fortunately the way regular components are inherited can be handled in |
| -- the same way in tagged and untagged types. |
| |
| -- To complicate things a bit more the private view of a private extension |
| -- cannot be handled in the same way as the full view (for one thing the |
| -- semantic rules are somewhat different). We will explain what differs |
| -- below. |
| |
| -- 2. DISCRIMINANTS UNDER INHERITANCE |
| |
| -- The semantic rules governing the discriminants of derived types are |
| -- quite subtle. |
| |
| -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new |
| -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART] |
| |
| -- If parent type has discriminants, then the discriminants that are |
| -- declared in the derived type are [3.4 (11)]: |
| |
| -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if |
| -- there is one; |
| |
| -- o Otherwise, each discriminant of the parent type (implicitly declared |
| -- in the same order with the same specifications). In this case, the |
| -- discriminants are said to be "inherited", or if unknown in the parent |
| -- are also unknown in the derived type. |
| |
| -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]: |
| |
| -- o The parent subtype shall be constrained; |
| |
| -- o If the parent type is not a tagged type, then each discriminant of |
| -- the derived type shall be used in the constraint defining a parent |
| -- subtype [Implementation note: this ensures that the new discriminant |
| -- can share storage with an existing discriminant.]. |
| |
| -- For the derived type each discriminant of the parent type is either |
| -- inherited, constrained to equal some new discriminant of the derived |
| -- type, or constrained to the value of an expression. |
| |
| -- When inherited or constrained to equal some new discriminant, the |
| -- parent discriminant and the discriminant of the derived type are said |
| -- to "correspond". |
| |
| -- If a discriminant of the parent type is constrained to a specific value |
| -- in the derived type definition, then the discriminant is said to be |
| -- "specified" by that derived type definition. |
| |
| -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES |
| |
| -- We have spoken about stored discriminants in point 1 (introduction) |
| -- above. There are two sort of stored discriminants: implicit and |
| -- explicit. As long as the derived type inherits the same discriminants as |
| -- the root record type, stored discriminants are the same as regular |
| -- discriminants, and are said to be implicit. However, if any discriminant |
| -- in the root type was renamed in the derived type, then the derived |
| -- type will contain explicit stored discriminants. Explicit stored |
| -- discriminants are discriminants in addition to the semantically visible |
| -- discriminants defined for the derived type. Stored discriminants are |
| -- used by Gigi to figure out what are the physical discriminants in |
| -- objects of the derived type (see precise definition in einfo.ads). |
| -- As an example, consider the following: |
| |
| -- type R (D1, D2, D3 : Int) is record ... end record; |
| -- type T1 is new R; |
| -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1); |
| -- type T3 is new T2; |
| -- type T4 (Y : Int) is new T3 (Y, 99); |
| |
| -- The following table summarizes the discriminants and stored |
| -- discriminants in R and T1 through T4. |
| |
| -- Type Discrim Stored Discrim Comment |
| -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R |
| -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1 |
| -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2 |
| -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3 |
| -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4 |
| |
| -- Field Corresponding_Discriminant (abbreviated CD below) allows us to |
| -- find the corresponding discriminant in the parent type, while |
| -- Original_Record_Component (abbreviated ORC below), the actual physical |
| -- component that is renamed. Finally the field Is_Completely_Hidden |
| -- (abbreviated ICH below) is set for all explicit stored discriminants |
| -- (see einfo.ads for more info). For the above example this gives: |
| |
| -- Discrim CD ORC ICH |
| -- ^^^^^^^ ^^ ^^^ ^^^ |
| -- D1 in R empty itself no |
| -- D2 in R empty itself no |
| -- D3 in R empty itself no |
| |
| -- D1 in T1 D1 in R itself no |
| -- D2 in T1 D2 in R itself no |
| -- D3 in T1 D3 in R itself no |
| |
| -- X1 in T2 D3 in T1 D3 in T2 no |
| -- X2 in T2 D1 in T1 D1 in T2 no |
| -- D1 in T2 empty itself yes |
| -- D2 in T2 empty itself yes |
| -- D3 in T2 empty itself yes |
| |
| -- X1 in T3 X1 in T2 D3 in T3 no |
| -- X2 in T3 X2 in T2 D1 in T3 no |
| -- D1 in T3 empty itself yes |
| -- D2 in T3 empty itself yes |
| -- D3 in T3 empty itself yes |
| |
| -- Y in T4 X1 in T3 D3 in T3 no |
| -- D1 in T3 empty itself yes |
| -- D2 in T3 empty itself yes |
| -- D3 in T3 empty itself yes |
| |
| -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES |
| |
| -- Type derivation for tagged types is fairly straightforward. if no |
| -- discriminants are specified by the derived type, these are inherited |
| -- from the parent. No explicit stored discriminants are ever necessary. |
| -- The only manipulation that is done to the tree is that of adding a |
| -- _parent field with parent type and constrained to the same constraint |
| -- specified for the parent in the derived type definition. For instance: |
| |
| -- type R (D1, D2, D3 : Int) is tagged record ... end record; |
| -- type T1 is new R with null record; |
| -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record; |
| |
| -- are changed into: |
| |
| -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record |
| -- _parent : R (D1, D2, D3); |
| -- end record; |
| |
| -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record |
| -- _parent : T1 (X2, 88, X1); |
| -- end record; |
| |
| -- The discriminants actually present in R, T1 and T2 as well as their CD, |
| -- ORC and ICH fields are: |
| |
| -- Discrim CD ORC ICH |
| -- ^^^^^^^ ^^ ^^^ ^^^ |
| -- D1 in R empty itself no |
| -- D2 in R empty itself no |
| -- D3 in R empty itself no |
| |
| -- D1 in T1 D1 in R D1 in R no |
| -- D2 in T1 D2 in R D2 in R no |
| -- D3 in T1 D3 in R D3 in R no |
| |
| -- X1 in T2 D3 in T1 D3 in R no |
| -- X2 in T2 D1 in T1 D1 in R no |
| |
| -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS |
| -- |
| -- Regardless of whether we dealing with a tagged or untagged type |
| -- we will transform all derived type declarations of the form |
| -- |
| -- type T is new R (...) [with ...]; |
| -- or |
| -- subtype S is R (...); |
| -- type T is new S [with ...]; |
| -- into |
| -- type BT is new R [with ...]; |
| -- subtype T is BT (...); |
| -- |
| -- That is, the base derived type is constrained only if it has no |
| -- discriminants. The reason for doing this is that GNAT's semantic model |
| -- assumes that a base type with discriminants is unconstrained. |
| -- |
| -- Note that, strictly speaking, the above transformation is not always |
| -- correct. Consider for instance the following excerpt from ACVC b34011a: |
| -- |
| -- procedure B34011A is |
| -- type REC (D : integer := 0) is record |
| -- I : Integer; |
| -- end record; |
| |
| -- package P is |
| -- type T6 is new Rec; |
| -- function F return T6; |
| -- end P; |
| |
| -- use P; |
| -- package Q6 is |
| -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F. |
| -- end Q6; |
| -- |
| -- The definition of Q6.U is illegal. However transforming Q6.U into |
| |
| -- type BaseU is new T6; |
| -- subtype U is BaseU (Q6.F.I) |
| |
| -- turns U into a legal subtype, which is incorrect. To avoid this problem |
| -- we always analyze the constraint (in this case (Q6.F.I)) before applying |
| -- the transformation described above. |
| |
| -- There is another instance where the above transformation is incorrect. |
| -- Consider: |
| |
| -- package Pack is |
| -- type Base (D : Integer) is tagged null record; |
| -- procedure P (X : Base); |
| |
| -- type Der is new Base (2) with null record; |
| -- procedure P (X : Der); |
| -- end Pack; |
| |
| -- Then the above transformation turns this into |
| |
| -- type Der_Base is new Base with null record; |
| -- -- procedure P (X : Base) is implicitly inherited here |
| -- -- as procedure P (X : Der_Base). |
| |
| -- subtype Der is Der_Base (2); |
| -- procedure P (X : Der); |
| -- -- The overriding of P (X : Der_Base) is illegal since we |
| -- -- have a parameter conformance problem. |
| |
| -- To get around this problem, after having semantically processed Der_Base |
| -- and the rewritten subtype declaration for Der, we copy Der_Base field |
| -- Discriminant_Constraint from Der so that when parameter conformance is |
| -- checked when P is overridden, no semantic errors are flagged. |
| |
| -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS |
| |
| -- Regardless of whether we are dealing with a tagged or untagged type |
| -- we will transform all derived type declarations of the form |
| |
| -- type R (D1, .., Dn : ...) is [tagged] record ...; |
| -- type T is new R [with ...]; |
| -- into |
| -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...]; |
| |
| -- The reason for such transformation is that it allows us to implement a |
| -- very clean form of component inheritance as explained below. |
| |
| -- Note that this transformation is not achieved by direct tree rewriting |
| -- and manipulation, but rather by redoing the semantic actions that the |
| -- above transformation will entail. This is done directly in routine |
| -- Inherit_Components. |
| |
| -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE |
| |
| -- In both tagged and untagged derived types, regular non discriminant |
| -- components are inherited in the derived type from the parent type. In |
| -- the absence of discriminants component, inheritance is straightforward |
| -- as components can simply be copied from the parent. |
| |
| -- If the parent has discriminants, inheriting components constrained with |
| -- these discriminants requires caution. Consider the following example: |
| |
| -- type R (D1, D2 : Positive) is [tagged] record |
| -- S : String (D1 .. D2); |
| -- end record; |
| |
| -- type T1 is new R [with null record]; |
| -- type T2 (X : positive) is new R (1, X) [with null record]; |
| |
| -- As explained in 6. above, T1 is rewritten as |
| -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record]; |
| -- which makes the treatment for T1 and T2 identical. |
| |
| -- What we want when inheriting S, is that references to D1 and D2 in R are |
| -- replaced with references to their correct constraints, ie D1 and D2 in |
| -- T1 and 1 and X in T2. So all R's discriminant references are replaced |
| -- with either discriminant references in the derived type or expressions. |
| -- This replacement is achieved as follows: before inheriting R's |
| -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is |
| -- created in the scope of T1 (resp. scope of T2) so that discriminants D1 |
| -- and D2 of T1 are visible (resp. discriminant X of T2 is visible). |
| -- For T2, for instance, this has the effect of replacing String (D1 .. D2) |
| -- by String (1 .. X). |
| |
| -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS |
| |
| -- We explain here the rules governing private type extensions relevant to |
| -- type derivation. These rules are explained on the following example: |
| |
| -- type D [(...)] is new A [(...)] with private; <-- partial view |
| -- type D [(...)] is new P [(...)] with null record; <-- full view |
| |
| -- Type A is called the ancestor subtype of the private extension. |
| -- Type P is the parent type of the full view of the private extension. It |
| -- must be A or a type derived from A. |
| |
| -- The rules concerning the discriminants of private type extensions are |
| -- [7.3(10-13)]: |
| |
| -- o If a private extension inherits known discriminants from the ancestor |
| -- subtype, then the full view shall also inherit its discriminants from |
| -- the ancestor subtype and the parent subtype of the full view shall be |
| -- constrained if and only if the ancestor subtype is constrained. |
| |
| -- o If a partial view has unknown discriminants, then the full view may |
| -- define a definite or an indefinite subtype, with or without |
| -- discriminants. |
| |
| -- o If a partial view has neither known nor unknown discriminants, then |
| -- the full view shall define a definite subtype. |
| |
| -- o If the ancestor subtype of a private extension has constrained |
| -- discriminants, then the parent subtype of the full view shall impose a |
| -- statically matching constraint on those discriminants. |
| |
| -- This means that only the following forms of private extensions are |
| -- allowed: |
| |
| -- type D is new A with private; <-- partial view |
| -- type D is new P with null record; <-- full view |
| |
| -- If A has no discriminants than P has no discriminants, otherwise P must |
| -- inherit A's discriminants. |
| |
| -- type D is new A (...) with private; <-- partial view |
| -- type D is new P (:::) with null record; <-- full view |
| |
| -- P must inherit A's discriminants and (...) and (:::) must statically |
| -- match. |
| |
| -- subtype A is R (...); |
| -- type D is new A with private; <-- partial view |
| -- type D is new P with null record; <-- full view |
| |
| -- P must have inherited R's discriminants and must be derived from A or |
| -- any of its subtypes. |
| |
| -- type D (..) is new A with private; <-- partial view |
| -- type D (..) is new P [(:::)] with null record; <-- full view |
| |
| -- No specific constraints on P's discriminants or constraint (:::). |
| -- Note that A can be unconstrained, but the parent subtype P must either |
| -- be constrained or (:::) must be present. |
| |
| -- type D (..) is new A [(...)] with private; <-- partial view |
| -- type D (..) is new P [(:::)] with null record; <-- full view |
| |
| -- P's constraints on A's discriminants must statically match those |
| -- imposed by (...). |
| |
| -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS |
| |
| -- The full view of a private extension is handled exactly as described |
| -- above. The model chose for the private view of a private extension is |
| -- the same for what concerns discriminants (ie they receive the same |
| -- treatment as in the tagged case). However, the private view of the |
| -- private extension always inherits the components of the parent base, |
| -- without replacing any discriminant reference. Strictly speaking this is |
| -- incorrect. However, Gigi never uses this view to generate code so this |
| -- is a purely semantic issue. In theory, a set of transformations similar |
| -- to those given in 5. and 6. above could be applied to private views of |
| -- private extensions to have the same model of component inheritance as |
| -- for non private extensions. However, this is not done because it would |
| -- further complicate private type processing. Semantically speaking, this |
| -- leaves us in an uncomfortable situation. As an example consider: |
| |
| -- package Pack is |
| -- type R (D : integer) is tagged record |
| -- S : String (1 .. D); |
| -- end record; |
| -- procedure P (X : R); |
| -- type T is new R (1) with private; |
| -- private |
| -- type T is new R (1) with null record; |
| -- end; |
| |
| -- This is transformed into: |
| |
| -- package Pack is |
| -- type R (D : integer) is tagged record |
| -- S : String (1 .. D); |
| -- end record; |
| -- procedure P (X : R); |
| -- type T is new R (1) with private; |
| -- private |
| -- type BaseT is new R with null record; |
| -- subtype T is BaseT (1); |
| -- end; |
| |
| -- (strictly speaking the above is incorrect Ada) |
| |
| -- From the semantic standpoint the private view of private extension T |
| -- should be flagged as constrained since one can clearly have |
| -- |
| -- Obj : T; |
| -- |
| -- in a unit withing Pack. However, when deriving subprograms for the |
| -- private view of private extension T, T must be seen as unconstrained |
| -- since T has discriminants (this is a constraint of the current |
| -- subprogram derivation model). Thus, when processing the private view of |
| -- a private extension such as T, we first mark T as unconstrained, we |
| -- process it, we perform program derivation and just before returning from |
| -- Build_Derived_Record_Type we mark T as constrained. |
| |
| -- ??? Are there are other uncomfortable cases that we will have to |
| -- deal with. |
| |
| -- 10. RECORD_TYPE_WITH_PRIVATE complications |
| |
| -- Types that are derived from a visible record type and have a private |
| -- extension present other peculiarities. They behave mostly like private |
| -- types, but if they have primitive operations defined, these will not |
| -- have the proper signatures for further inheritance, because other |
| -- primitive operations will use the implicit base that we define for |
| -- private derivations below. This affect subprogram inheritance (see |
| -- Derive_Subprograms for details). We also derive the implicit base from |
| -- the base type of the full view, so that the implicit base is a record |
| -- type and not another private type, This avoids infinite loops. |
| |
| procedure Build_Derived_Record_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id; |
| Derive_Subps : Boolean := True) |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| Parent_Base : Entity_Id; |
| Type_Def : Node_Id; |
| Indic : Node_Id; |
| Discrim : Entity_Id; |
| Last_Discrim : Entity_Id; |
| Constrs : Elist_Id; |
| |
| Discs : Elist_Id := New_Elmt_List; |
| -- An empty Discs list means that there were no constraints in the |
| -- subtype indication or that there was an error processing it. |
| |
| Assoc_List : Elist_Id; |
| New_Discrs : Elist_Id; |
| New_Base : Entity_Id; |
| New_Decl : Node_Id; |
| New_Indic : Node_Id; |
| |
| Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type); |
| Discriminant_Specs : constant Boolean := |
| Present (Discriminant_Specifications (N)); |
| Private_Extension : constant Boolean := |
| (Nkind (N) = N_Private_Extension_Declaration); |
| |
| Constraint_Present : Boolean; |
| Has_Interfaces : Boolean := False; |
| Inherit_Discrims : Boolean := False; |
| Tagged_Partial_View : Entity_Id; |
| Save_Etype : Entity_Id; |
| Save_Discr_Constr : Elist_Id; |
| Save_Next_Entity : Entity_Id; |
| |
| begin |
| if Ekind (Parent_Type) = E_Record_Type_With_Private |
| and then Present (Full_View (Parent_Type)) |
| and then Has_Discriminants (Parent_Type) |
| then |
| Parent_Base := Base_Type (Full_View (Parent_Type)); |
| else |
| Parent_Base := Base_Type (Parent_Type); |
| end if; |
| |
| -- Before we start the previously documented transformations, here is |
| -- a little fix for size and alignment of tagged types. Normally when |
| -- we derive type D from type P, we copy the size and alignment of P |
| -- as the default for D, and in the absence of explicit representation |
| -- clauses for D, the size and alignment are indeed the same as the |
| -- parent. |
| |
| -- But this is wrong for tagged types, since fields may be added, |
| -- and the default size may need to be larger, and the default |
| -- alignment may need to be larger. |
| |
| -- We therefore reset the size and alignment fields in the tagged |
| -- case. Note that the size and alignment will in any case be at |
| -- least as large as the parent type (since the derived type has |
| -- a copy of the parent type in the _parent field) |
| |
| if Is_Tagged then |
| Init_Size_Align (Derived_Type); |
| end if; |
| |
| -- STEP 0a: figure out what kind of derived type declaration we have |
| |
| if Private_Extension then |
| Type_Def := N; |
| Set_Ekind (Derived_Type, E_Record_Type_With_Private); |
| |
| else |
| Type_Def := Type_Definition (N); |
| |
| -- Ekind (Parent_Base) in not necessarily E_Record_Type since |
| -- Parent_Base can be a private type or private extension. However, |
| -- for tagged types with an extension the newly added fields are |
| -- visible and hence the Derived_Type is always an E_Record_Type. |
| -- (except that the parent may have its own private fields). |
| -- For untagged types we preserve the Ekind of the Parent_Base. |
| |
| if Present (Record_Extension_Part (Type_Def)) then |
| Set_Ekind (Derived_Type, E_Record_Type); |
| else |
| Set_Ekind (Derived_Type, Ekind (Parent_Base)); |
| end if; |
| end if; |
| |
| -- Indic can either be an N_Identifier if the subtype indication |
| -- contains no constraint or an N_Subtype_Indication if the subtype |
| -- indication has a constraint. |
| |
| Indic := Subtype_Indication (Type_Def); |
| Constraint_Present := (Nkind (Indic) = N_Subtype_Indication); |
| |
| -- Check that the type has visible discriminants. The type may be |
| -- a private type with unknown discriminants whose full view has |
| -- discriminants which are invisible. |
| |
| if Constraint_Present then |
| if not Has_Discriminants (Parent_Base) |
| or else |
| (Has_Unknown_Discriminants (Parent_Base) |
| and then Is_Private_Type (Parent_Base)) |
| then |
| Error_Msg_N |
| ("invalid constraint: type has no discriminant", |
| Constraint (Indic)); |
| |
| Constraint_Present := False; |
| Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic))); |
| |
| elsif Is_Constrained (Parent_Type) then |
| Error_Msg_N |
| ("invalid constraint: parent type is already constrained", |
| Constraint (Indic)); |
| |
| Constraint_Present := False; |
| Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic))); |
| end if; |
| end if; |
| |
| -- STEP 0b: If needed, apply transformation given in point 5. above |
| |
| if not Private_Extension |
| and then Has_Discriminants (Parent_Type) |
| and then not Discriminant_Specs |
| and then (Is_Constrained (Parent_Type) or else Constraint_Present) |
| then |
| -- First, we must analyze the constraint (see comment in point 5.) |
| |
| if Constraint_Present then |
| New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic); |
| |
| if Has_Discriminants (Derived_Type) |
| and then Has_Private_Declaration (Derived_Type) |
| and then Present (Discriminant_Constraint (Derived_Type)) |
| then |
| -- Verify that constraints of the full view conform to those |
| -- given in partial view. |
| |
| declare |
| C1, C2 : Elmt_Id; |
| |
| begin |
| C1 := First_Elmt (New_Discrs); |
| C2 := First_Elmt (Discriminant_Constraint (Derived_Type)); |
| while Present (C1) and then Present (C2) loop |
| if not |
| Fully_Conformant_Expressions (Node (C1), Node (C2)) |
| then |
| Error_Msg_N ( |
| "constraint not conformant to previous declaration", |
| Node (C1)); |
| end if; |
| |
| Next_Elmt (C1); |
| Next_Elmt (C2); |
| end loop; |
| end; |
| end if; |
| end if; |
| |
| -- Insert and analyze the declaration for the unconstrained base type |
| |
| New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B'); |
| |
| New_Decl := |
| Make_Full_Type_Declaration (Loc, |
| Defining_Identifier => New_Base, |
| Type_Definition => |
| Make_Derived_Type_Definition (Loc, |
| Abstract_Present => Abstract_Present (Type_Def), |
| Subtype_Indication => |
| New_Occurrence_Of (Parent_Base, Loc), |
| Record_Extension_Part => |
| Relocate_Node (Record_Extension_Part (Type_Def)))); |
| |
| Set_Parent (New_Decl, Parent (N)); |
| Mark_Rewrite_Insertion (New_Decl); |
| Insert_Before (N, New_Decl); |
| |
| -- Note that this call passes False for the Derive_Subps parameter |
| -- because subprogram derivation is deferred until after creating |
| -- the subtype (see below). |
| |
| Build_Derived_Type |
| (New_Decl, Parent_Base, New_Base, |
| Is_Completion => True, Derive_Subps => False); |
| |
| -- ??? This needs re-examination to determine whether the |
| -- above call can simply be replaced by a call to Analyze. |
| |
| Set_Analyzed (New_Decl); |
| |
| -- Insert and analyze the declaration for the constrained subtype |
| |
| if Constraint_Present then |
| New_Indic := |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Occurrence_Of (New_Base, Loc), |
| Constraint => Relocate_Node (Constraint (Indic))); |
| |
| else |
| declare |
| Constr_List : constant List_Id := New_List; |
| C : Elmt_Id; |
| Expr : Node_Id; |
| |
| begin |
| C := First_Elmt (Discriminant_Constraint (Parent_Type)); |
| while Present (C) loop |
| Expr := Node (C); |
| |
| -- It is safe here to call New_Copy_Tree since |
| -- Force_Evaluation was called on each constraint in |
| -- Build_Discriminant_Constraints. |
| |
| Append (New_Copy_Tree (Expr), To => Constr_List); |
| |
| Next_Elmt (C); |
| end loop; |
| |
| New_Indic := |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Occurrence_Of (New_Base, Loc), |
| Constraint => |
| Make_Index_Or_Discriminant_Constraint (Loc, Constr_List)); |
| end; |
| end if; |
| |
| Rewrite (N, |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Derived_Type, |
| Subtype_Indication => New_Indic)); |
| |
| Analyze (N); |
| |
| -- Derivation of subprograms must be delayed until the full subtype |
| -- has been established to ensure proper overriding of subprograms |
| -- inherited by full types. If the derivations occurred as part of |
| -- the call to Build_Derived_Type above, then the check for type |
| -- conformance would fail because earlier primitive subprograms |
| -- could still refer to the full type prior the change to the new |
| -- subtype and hence would not match the new base type created here. |
| |
| Derive_Subprograms (Parent_Type, Derived_Type); |
| |
| -- For tagged types the Discriminant_Constraint of the new base itype |
| -- is inherited from the first subtype so that no subtype conformance |
| -- problem arise when the first subtype overrides primitive |
| -- operations inherited by the implicit base type. |
| |
| if Is_Tagged then |
| Set_Discriminant_Constraint |
| (New_Base, Discriminant_Constraint (Derived_Type)); |
| end if; |
| |
| return; |
| end if; |
| |
| -- If we get here Derived_Type will have no discriminants or it will be |
| -- a discriminated unconstrained base type. |
| |
| -- STEP 1a: perform preliminary actions/checks for derived tagged types |
| |
| if Is_Tagged then |
| |
| -- The parent type is frozen for non-private extensions (RM 13.14(7)) |
| |
| if not Private_Extension then |
| Freeze_Before (N, Parent_Type); |
| end if; |
| |
| -- In Ada 2005 (AI-344), the restriction that a derived tagged type |
| -- cannot be declared at a deeper level than its parent type is |
| -- removed. The check on derivation within a generic body is also |
| -- relaxed, but there's a restriction that a derived tagged type |
| -- cannot be declared in a generic body if it's derived directly |
| -- or indirectly from a formal type of that generic. |
| |
| if Ada_Version >= Ada_05 then |
| if Present (Enclosing_Generic_Body (Derived_Type)) then |
| declare |
| Ancestor_Type : Entity_Id; |
| |
| begin |
| -- Check to see if any ancestor of the derived type is a |
| -- formal type. |
| |
| Ancestor_Type := Parent_Type; |
| while not Is_Generic_Type (Ancestor_Type) |
| and then Etype (Ancestor_Type) /= Ancestor_Type |
| loop |
| Ancestor_Type := Etype (Ancestor_Type); |
| end loop; |
| |
| -- If the derived type does have a formal type as an |
| -- ancestor, then it's an error if the derived type is |
| -- declared within the body of the generic unit that |
| -- declares the formal type in its generic formal part. It's |
| -- sufficient to check whether the ancestor type is declared |
| -- inside the same generic body as the derived type (such as |
| -- within a nested generic spec), in which case the |
| -- derivation is legal. If the formal type is declared |
| -- outside of that generic body, then it's guaranteed that |
| -- the derived type is declared within the generic body of |
| -- the generic unit declaring the formal type. |
| |
| if Is_Generic_Type (Ancestor_Type) |
| and then Enclosing_Generic_Body (Ancestor_Type) /= |
| Enclosing_Generic_Body (Derived_Type) |
| then |
| Error_Msg_NE |
| ("parent type of& must not be descendant of formal type" |
| & " of an enclosing generic body", |
| Indic, Derived_Type); |
| end if; |
| end; |
| end if; |
| |
| elsif Type_Access_Level (Derived_Type) /= |
| Type_Access_Level (Parent_Type) |
| and then not Is_Generic_Type (Derived_Type) |
| then |
| if Is_Controlled (Parent_Type) then |
| Error_Msg_N |
| ("controlled type must be declared at the library level", |
| Indic); |
| else |
| Error_Msg_N |
| ("type extension at deeper accessibility level than parent", |
| Indic); |
| end if; |
| |
| else |
| declare |
| GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type); |
| |
| begin |
| if Present (GB) |
| and then GB /= Enclosing_Generic_Body (Parent_Base) |
| then |
| Error_Msg_NE |
| ("parent type of& must not be outside generic body" |
| & " ('R'M 3.9.1(4))", |
| Indic, Derived_Type); |
| end if; |
| end; |
| end if; |
| end if; |
| |
| -- Ada 2005 (AI-251) |
| |
| if Ada_Version = Ada_05 |
| and then Is_Tagged |
| then |
| |
| -- "The declaration of a specific descendant of an interface type |
| -- freezes the interface type" (RM 13.14). |
| |
| declare |
| Iface : Node_Id; |
| begin |
| if Is_Non_Empty_List (Interface_List (Type_Def)) then |
| Iface := First (Interface_List (Type_Def)); |
| while Present (Iface) loop |
| Freeze_Before (N, Etype (Iface)); |
| Next (Iface); |
| end loop; |
| end if; |
| end; |
| end if; |
| |
| -- STEP 1b : preliminary cleanup of the full view of private types |
| |
| -- If the type is already marked as having discriminants, then it's the |
| -- completion of a private type or private extension and we need to |
| -- retain the discriminants from the partial view if the current |
| -- declaration has Discriminant_Specifications so that we can verify |
| -- conformance. However, we must remove any existing components that |
| -- were inherited from the parent (and attached in Copy_And_Swap) |
| -- because the full type inherits all appropriate components anyway, and |
| -- we do not want the partial view's components interfering. |
| |
| if Has_Discriminants (Derived_Type) and then Discriminant_Specs then |
| Discrim := First_Discriminant (Derived_Type); |
| loop |
| Last_Discrim := Discrim; |
| Next_Discriminant (Discrim); |
| exit when No (Discrim); |
| end loop; |
| |
| Set_Last_Entity (Derived_Type, Last_Discrim); |
| |
| -- In all other cases wipe out the list of inherited components (even |
| -- inherited discriminants), it will be properly rebuilt here. |
| |
| else |
| Set_First_Entity (Derived_Type, Empty); |
| Set_Last_Entity (Derived_Type, Empty); |
| end if; |
| |
| -- STEP 1c: Initialize some flags for the Derived_Type |
| |
| -- The following flags must be initialized here so that |
| -- Process_Discriminants can check that discriminants of tagged types |
| -- do not have a default initial value and that access discriminants |
| -- are only specified for limited records. For completeness, these |
| -- flags are also initialized along with all the other flags below. |
| |
| -- AI-419: limitedness is not inherited from an interface parent |
| |
| Set_Is_Tagged_Type (Derived_Type, Is_Tagged); |
| Set_Is_Limited_Record (Derived_Type, |
| Is_Limited_Record (Parent_Type) |
| and then not Is_Interface (Parent_Type)); |
| |
| -- STEP 2a: process discriminants of derived type if any |
| |
| New_Scope (Derived_Type); |
| |
| if Discriminant_Specs then |
| Set_Has_Unknown_Discriminants (Derived_Type, False); |
| |
| -- The following call initializes fields Has_Discriminants and |
| -- Discriminant_Constraint, unless we are processing the completion |
| -- of a private type declaration. |
| |
| Check_Or_Process_Discriminants (N, Derived_Type); |
| |
| -- For non-tagged types the constraint on the Parent_Type must be |
| -- present and is used to rename the discriminants. |
| |
| if not Is_Tagged and then not Has_Discriminants (Parent_Type) then |
| Error_Msg_N ("untagged parent must have discriminants", Indic); |
| |
| elsif not Is_Tagged and then not Constraint_Present then |
| Error_Msg_N |
| ("discriminant constraint needed for derived untagged records", |
| Indic); |
| |
| -- Otherwise the parent subtype must be constrained unless we have a |
| -- private extension. |
| |
| elsif not Constraint_Present |
| and then not Private_Extension |
| and then not Is_Constrained (Parent_Type) |
| then |
| Error_Msg_N |
| ("unconstrained type not allowed in this context", Indic); |
| |
| elsif Constraint_Present then |
| -- The following call sets the field Corresponding_Discriminant |
| -- for the discriminants in the Derived_Type. |
| |
| Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True); |
| |
| -- For untagged types all new discriminants must rename |
| -- discriminants in the parent. For private extensions new |
| -- discriminants cannot rename old ones (implied by [7.3(13)]). |
| |
| Discrim := First_Discriminant (Derived_Type); |
| while Present (Discrim) loop |
| if not Is_Tagged |
| and then No (Corresponding_Discriminant (Discrim)) |
| then |
| Error_Msg_N |
| ("new discriminants must constrain old ones", Discrim); |
| |
| elsif Private_Extension |
| and then Present (Corresponding_Discriminant (Discrim)) |
| then |
| Error_Msg_N |
| ("only static constraints allowed for parent" |
| & " discriminants in the partial view", Indic); |
| exit; |
| end if; |
| |
| -- If a new discriminant is used in the constraint, then its |
| -- subtype must be statically compatible with the parent |
| -- discriminant's subtype (3.7(15)). |
| |
| if Present (Corresponding_Discriminant (Discrim)) |
| and then |
| not Subtypes_Statically_Compatible |
| (Etype (Discrim), |
| Etype (Corresponding_Discriminant (Discrim))) |
| then |
| Error_Msg_N |
| ("subtype must be compatible with parent discriminant", |
| Discrim); |
| end if; |
| |
| Next_Discriminant (Discrim); |
| end loop; |
| |
| -- Check whether the constraints of the full view statically |
| -- match those imposed by the parent subtype [7.3(13)]. |
| |
| if Present (Stored_Constraint (Derived_Type)) then |
| declare |
| C1, C2 : Elmt_Id; |
| |
| begin |
| C1 := First_Elmt (Discs); |
| C2 := First_Elmt (Stored_Constraint (Derived_Type)); |
| while Present (C1) and then Present (C2) loop |
| if not |
| Fully_Conformant_Expressions (Node (C1), Node (C2)) |
| then |
| Error_Msg_N ( |
| "not conformant with previous declaration", |
| Node (C1)); |
| end if; |
| |
| Next_Elmt (C1); |
| Next_Elmt (C2); |
| end loop; |
| end; |
| end if; |
| end if; |
| |
| -- STEP 2b: No new discriminants, inherit discriminants if any |
| |
| else |
| if Private_Extension then |
| Set_Has_Unknown_Discriminants |
| (Derived_Type, |
| Has_Unknown_Discriminants (Parent_Type) |
| or else Unknown_Discriminants_Present (N)); |
| |
| -- The partial view of the parent may have unknown discriminants, |
| -- but if the full view has discriminants and the parent type is |
| -- in scope they must be inherited. |
| |
| elsif Has_Unknown_Discriminants (Parent_Type) |
| and then |
| (not Has_Discriminants (Parent_Type) |
| or else not In_Open_Scopes (Scope (Parent_Type))) |
| then |
| Set_Has_Unknown_Discriminants (Derived_Type); |
| end if; |
| |
| if not Has_Unknown_Discriminants (Derived_Type) |
| and then not Has_Unknown_Discriminants (Parent_Base) |
| and then Has_Discriminants (Parent_Type) |
| then |
| Inherit_Discrims := True; |
| Set_Has_Discriminants |
| (Derived_Type, True); |
| Set_Discriminant_Constraint |
| (Derived_Type, Discriminant_Constraint (Parent_Base)); |
| end if; |
| |
| -- The following test is true for private types (remember |
| -- transformation 5. is not applied to those) and in an error |
| -- situation. |
| |
| if Constraint_Present then |
| Discs := Build_Discriminant_Constraints (Parent_Type, Indic); |
| end if; |
| |
| -- For now mark a new derived type as constrained only if it has no |
| -- discriminants. At the end of Build_Derived_Record_Type we properly |
| -- set this flag in the case of private extensions. See comments in |
| -- point 9. just before body of Build_Derived_Record_Type. |
| |
| Set_Is_Constrained |
| (Derived_Type, |
| not (Inherit_Discrims |
| or else Has_Unknown_Discriminants (Derived_Type))); |
| end if; |
| |
| -- STEP 3: initialize fields of derived type |
| |
| Set_Is_Tagged_Type (Derived_Type, Is_Tagged); |
| Set_Stored_Constraint (Derived_Type, No_Elist); |
| |
| -- Ada 2005 (AI-251): Private type-declarations can implement interfaces |
| -- but cannot be interfaces |
| |
| if not Private_Extension |
| and then Ekind (Derived_Type) /= E_Private_Type |
| and then Ekind (Derived_Type) /= E_Limited_Private_Type |
| then |
| Set_Is_Interface (Derived_Type, Interface_Present (Type_Def)); |
| Set_Abstract_Interfaces (Derived_Type, No_Elist); |
| end if; |
| |
| -- Fields inherited from the Parent_Type |
| |
| Set_Discard_Names |
| (Derived_Type, Einfo.Discard_Names (Parent_Type)); |
| Set_Has_Specified_Layout |
| (Derived_Type, Has_Specified_Layout (Parent_Type)); |
| Set_Is_Limited_Composite |
| (Derived_Type, Is_Limited_Composite (Parent_Type)); |
| Set_Is_Limited_Record |
| (Derived_Type, |
| Is_Limited_Record (Parent_Type) |
| and then not Is_Interface (Parent_Type)); |
| Set_Is_Private_Composite |
| (Derived_Type, Is_Private_Composite (Parent_Type)); |
| |
| -- Fields inherited from the Parent_Base |
| |
| Set_Has_Controlled_Component |
| (Derived_Type, Has_Controlled_Component (Parent_Base)); |
| Set_Has_Non_Standard_Rep |
| (Derived_Type, Has_Non_Standard_Rep (Parent_Base)); |
| Set_Has_Primitive_Operations |
| (Derived_Type, Has_Primitive_Operations (Parent_Base)); |
| |
| -- Direct controlled types do not inherit Finalize_Storage_Only flag |
| |
| if not Is_Controlled (Parent_Type) then |
| Set_Finalize_Storage_Only |
| (Derived_Type, Finalize_Storage_Only (Parent_Type)); |
| end if; |
| |
| -- Set fields for private derived types |
| |
| if Is_Private_Type (Derived_Type) then |
| Set_Depends_On_Private (Derived_Type, True); |
| Set_Private_Dependents (Derived_Type, New_Elmt_List); |
| |
| -- Inherit fields from non private record types. If this is the |
| -- completion of a derivation from a private type, the parent itself |
| -- is private, and the attributes come from its full view, which must |
| -- be present. |
| |
| else |
| if Is_Private_Type (Parent_Base) |
| and then not Is_Record_Type (Parent_Base) |
| then |
| Set_Component_Alignment |
| (Derived_Type, Component_Alignment (Full_View (Parent_Base))); |
| Set_C_Pass_By_Copy |
| (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base))); |
| else |
| Set_Component_Alignment |
| (Derived_Type, Component_Alignment (Parent_Base)); |
| |
| Set_C_Pass_By_Copy |
| (Derived_Type, C_Pass_By_Copy (Parent_Base)); |
| end if; |
| end if; |
| |
| -- Set fields for tagged types |
| |
| if Is_Tagged then |
| Set_Primitive_Operations (Derived_Type, New_Elmt_List); |
| |
| -- All tagged types defined in Ada.Finalization are controlled |
| |
| if Chars (Scope (Derived_Type)) = Name_Finalization |
| and then Chars (Scope (Scope (Derived_Type))) = Name_Ada |
| and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard |
| then |
| Set_Is_Controlled (Derived_Type); |
| else |
| Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base)); |
| end if; |
| |
| Make_Class_Wide_Type (Derived_Type); |
| Set_Is_Abstract (Derived_Type, Abstract_Present (Type_Def)); |
| |
| if Has_Discriminants (Derived_Type) |
| and then Constraint_Present |
| then |
| Set_Stored_Constraint |
| (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs)); |
| end if; |
| |
| -- Ada 2005 (AI-251): Look for the partial view of tagged types |
| -- declared in the private part. This will be used 1) to check that |
| -- the set of interfaces in both views is equal, and 2) to complete |
| -- the derivation of subprograms covering interfaces. |
| |
| Tagged_Partial_View := Empty; |
| |
| if Has_Private_Declaration (Derived_Type) then |
| Tagged_Partial_View := Next_Entity (Derived_Type); |
| loop |
| exit when Has_Private_Declaration (Tagged_Partial_View) |
| and then Full_View (Tagged_Partial_View) = Derived_Type; |
| |
| Next_Entity (Tagged_Partial_View); |
| end loop; |
| end if; |
| |
| -- Ada 2005 (AI-251): Collect the whole list of implemented |
| -- interfaces. |
| |
| if Ada_Version >= Ada_05 then |
| Set_Abstract_Interfaces (Derived_Type, New_Elmt_List); |
| |
| if Nkind (N) = N_Private_Extension_Declaration then |
| Collect_Interfaces (N, Derived_Type); |
| else |
| Collect_Interfaces (Type_Definition (N), Derived_Type); |
| end if; |
| end if; |
| |
| else |
| Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base)); |
| Set_Has_Non_Standard_Rep |
| (Derived_Type, Has_Non_Standard_Rep (Parent_Base)); |
| end if; |
| |
| -- STEP 4: Inherit components from the parent base and constrain them. |
| -- Apply the second transformation described in point 6. above. |
| |
| if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims) |
| or else not Has_Discriminants (Parent_Type) |
| or else not Is_Constrained (Parent_Type) |
| then |
| Constrs := Discs; |
| else |
| Constrs := Discriminant_Constraint (Parent_Type); |
| end if; |
| |
| Assoc_List := |
| Inherit_Components |
| (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs); |
| |
| -- STEP 5a: Copy the parent record declaration for untagged types |
| |
| if not Is_Tagged then |
| |
| -- Discriminant_Constraint (Derived_Type) has been properly |
| -- constructed. Save it and temporarily set it to Empty because we |
| -- do not want the call to New_Copy_Tree below to mess this list. |
| |
| if Has_Discriminants (Derived_Type) then |
| Save_Discr_Constr := Discriminant_Constraint (Derived_Type); |
| Set_Discriminant_Constraint (Derived_Type, No_Elist); |
| else |
| Save_Discr_Constr := No_Elist; |
| end if; |
| |
| -- Save the Etype field of Derived_Type. It is correctly set now, |
| -- but the call to New_Copy tree may remap it to point to itself, |
| -- which is not what we want. Ditto for the Next_Entity field. |
| |
| Save_Etype := Etype (Derived_Type); |
| Save_Next_Entity := Next_Entity (Derived_Type); |
| |
| -- Assoc_List maps all stored discriminants in the Parent_Base to |
| -- stored discriminants in the Derived_Type. It is fundamental that |
| -- no types or itypes with discriminants other than the stored |
| -- discriminants appear in the entities declared inside |
| -- Derived_Type, since the back end cannot deal with it. |
| |
| New_Decl := |
| New_Copy_Tree |
| (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc); |
| |
| -- Restore the fields saved prior to the New_Copy_Tree call |
| -- and compute the stored constraint. |
| |
| Set_Etype (Derived_Type, Save_Etype); |
| Set_Next_Entity (Derived_Type, Save_Next_Entity); |
| |
| if Has_Discriminants (Derived_Type) then |
| Set_Discriminant_Constraint |
| (Derived_Type, Save_Discr_Constr); |
| Set_Stored_Constraint |
| (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs)); |
| Replace_Components (Derived_Type, New_Decl); |
| end if; |
| |
| -- Insert the new derived type declaration |
| |
| Rewrite (N, New_Decl); |
| |
| -- STEP 5b: Complete the processing for record extensions in generics |
| |
| -- There is no completion for record extensions declared in the |
| -- parameter part of a generic, so we need to complete processing for |
| -- these generic record extensions here. The Record_Type_Definition call |
| -- will change the Ekind of the components from E_Void to E_Component. |
| |
| elsif Private_Extension and then Is_Generic_Type (Derived_Type) then |
| Record_Type_Definition (Empty, Derived_Type); |
| |
| -- STEP 5c: Process the record extension for non private tagged types |
| |
| elsif not Private_Extension then |
| |
| -- Add the _parent field in the derived type |
| |
| Expand_Record_Extension (Derived_Type, Type_Def); |
| |
| -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the |
| -- implemented interfaces if we are in expansion mode |
| |
| if Expander_Active then |
| Add_Interface_Tag_Components (N, Derived_Type); |
| end if; |
| |
| -- Analyze the record extension |
| |
| Record_Type_Definition |
| (Record_Extension_Part (Type_Def), Derived_Type); |
| end if; |
| |
| End_Scope; |
| |
| if Etype (Derived_Type) = Any_Type then |
| return; |
| end if; |
| |
| -- Set delayed freeze and then derive subprograms, we need to do |
| -- this in this order so that derived subprograms inherit the |
| -- derived freeze if necessary. |
| |
| Set_Has_Delayed_Freeze (Derived_Type); |
| |
| if Derive_Subps then |
| |
| -- Ada 2005 (AI-251): Check if this tagged type implements abstract |
| -- interfaces |
| |
| Has_Interfaces := False; |
| |
| if Is_Tagged_Type (Derived_Type) then |
| declare |
| E : Entity_Id; |
| |
| begin |
| -- Handle private types |
| |
| if Present (Full_View (Derived_Type)) then |
| E := Full_View (Derived_Type); |
| else |
| E := Derived_Type; |
| end if; |
| |
| loop |
| if Is_Interface (E) |
| or else (Present (Abstract_Interfaces (E)) |
| and then |
| not Is_Empty_Elmt_List (Abstract_Interfaces (E))) |
| then |
| Has_Interfaces := True; |
| exit; |
| end if; |
| |
| exit when Etype (E) = E |
| |
| -- Handle private types |
| |
| or else (Present (Full_View (Etype (E))) |
| and then Full_View (Etype (E)) = E) |
| |
| -- Protect the frontend against wrong source |
| |
| or else Etype (E) = Derived_Type; |
| |
| -- Climb to the ancestor type handling private types |
| |
| if Present (Full_View (Etype (E))) then |
| E := Full_View (Etype (E)); |
| else |
| E := Etype (E); |
| end if; |
| end loop; |
| end; |
| end if; |
| |
| Derive_Subprograms (Parent_Type, Derived_Type); |
| |
| -- Ada 2005 (AI-251): Handle tagged types implementing interfaces |
| |
| if Is_Tagged_Type (Derived_Type) |
| and then Has_Interfaces |
| then |
| -- Ada 2005 (AI-251): If we are analyzing a full view that has |
| -- no partial view we derive the abstract interface Subprograms |
| |
| if No (Tagged_Partial_View) then |
| Derive_Interface_Subprograms (Derived_Type); |
| |
| -- Ada 2005 (AI-251): if we are analyzing a full view that has |
| -- a partial view we complete the derivation of the subprograms |
| |
| else |
| Complete_Subprograms_Derivation |
| (Partial_View => Tagged_Partial_View, |
| Derived_Type => Derived_Type); |
| end if; |
| |
| -- Ada 2005 (AI-251): In both cases we check if some of the |
| -- inherited subprograms cover interface primitives. |
| |
| declare |
| Iface_Subp : Entity_Id; |
| Iface_Subp_Elmt : Elmt_Id; |
| Prev_Alias : Entity_Id; |
| Subp : Entity_Id; |
| Subp_Elmt : Elmt_Id; |
| |
| begin |
| Iface_Subp_Elmt := |
| First_Elmt (Primitive_Operations (Derived_Type)); |
| while Present (Iface_Subp_Elmt) loop |
| Iface_Subp := Node (Iface_Subp_Elmt); |
| |
| -- Look for an abstract interface subprogram |
| |
| if Is_Abstract (Iface_Subp) |
| and then Present (Alias (Iface_Subp)) |
| and then Present (DTC_Entity (Alias (Iface_Subp))) |
| and then Is_Interface |
| (Scope (DTC_Entity (Alias (Iface_Subp)))) |
| then |
| -- Look for candidate primitive subprograms of the tagged |
| -- type that can cover this interface subprogram. |
| |
| Subp_Elmt := |
| First_Elmt (Primitive_Operations (Derived_Type)); |
| while Present (Subp_Elmt) loop |
| Subp := Node (Subp_Elmt); |
| |
| if not Is_Abstract (Subp) |
| and then Chars (Subp) = Chars (Iface_Subp) |
| and then Type_Conformant (Iface_Subp, Subp) |
| then |
| Prev_Alias := Alias (Iface_Subp); |
| |
| Check_Dispatching_Operation |
| (Subp => Subp, |
| Old_Subp => Iface_Subp); |
| |
| pragma Assert |
| (Alias (Iface_Subp) = Subp); |
| pragma Assert |
| (Abstract_Interface_Alias (Iface_Subp) |
| = Prev_Alias); |
| |
| -- Traverse the list of aliased subprograms to link |
| -- subp with its ultimate aliased subprogram. This |
| -- avoids problems with the backend. |
| |
| declare |
| E : Entity_Id; |
| |
| begin |
| E := Alias (Subp); |
| while Present (Alias (E)) loop |
| E := Alias (E); |
| end loop; |
| |
| Set_Alias (Subp, E); |
| end; |
| |
| Set_Has_Delayed_Freeze (Subp); |
| exit; |
| end if; |
| |
| Next_Elmt (Subp_Elmt); |
| end loop; |
| end if; |
| |
| Next_Elmt (Iface_Subp_Elmt); |
| end loop; |
| end; |
| end if; |
| end if; |
| |
| -- If we have a private extension which defines a constrained derived |
| -- type mark as constrained here after we have derived subprograms. See |
| -- comment on point 9. just above the body of Build_Derived_Record_Type. |
| |
| if Private_Extension and then Inherit_Discrims then |
| if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then |
| Set_Is_Constrained (Derived_Type, True); |
| Set_Discriminant_Constraint (Derived_Type, Discs); |
| |
| elsif Is_Constrained (Parent_Type) then |
| Set_Is_Constrained |
| (Derived_Type, True); |
| Set_Discriminant_Constraint |
| (Derived_Type, Discriminant_Constraint (Parent_Type)); |
| end if; |
| end if; |
| |
| -- Update the class_wide type, which shares the now-completed |
| -- entity list with its specific type. |
| |
| if Is_Tagged then |
| Set_First_Entity |
| (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type)); |
| Set_Last_Entity |
| (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type)); |
| end if; |
| |
| end Build_Derived_Record_Type; |
| |
| ------------------------ |
| -- Build_Derived_Type -- |
| ------------------------ |
| |
| procedure Build_Derived_Type |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id; |
| Is_Completion : Boolean; |
| Derive_Subps : Boolean := True) |
| is |
| Parent_Base : constant Entity_Id := Base_Type (Parent_Type); |
| |
| begin |
| -- Set common attributes |
| |
| Set_Scope (Derived_Type, Current_Scope); |
| |
| Set_Ekind (Derived_Type, Ekind (Parent_Base)); |
| Set_Etype (Derived_Type, Parent_Base); |
| Set_Has_Task (Derived_Type, Has_Task (Parent_Base)); |
| |
| Set_Size_Info (Derived_Type, Parent_Type); |
| Set_RM_Size (Derived_Type, RM_Size (Parent_Type)); |
| Set_Convention (Derived_Type, Convention (Parent_Type)); |
| Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type)); |
| |
| -- The derived type inherits the representation clauses of the parent. |
| -- However, for a private type that is completed by a derivation, there |
| -- may be operation attributes that have been specified already (stream |
| -- attributes and External_Tag) and those must be provided. Finally, |
| -- if the partial view is a private extension, the representation items |
| -- of the parent have been inherited already, and should not be chained |
| -- twice to the derived type. |
| |
| if Is_Tagged_Type (Parent_Type) |
| and then Present (First_Rep_Item (Derived_Type)) |
| then |
| -- The existing items are either operational items or items inherited |
| -- from a private extension declaration. |
| |
| declare |
| Rep : Node_Id; |
| Found : Boolean := False; |
| |
| begin |
| Rep := First_Rep_Item (Derived_Type); |
| while Present (Rep) loop |
| if Rep = First_Rep_Item (Parent_Type) then |
| Found := True; |
| exit; |
| else |
| Rep := Next_Rep_Item (Rep); |
| end if; |
| end loop; |
| |
| if not Found then |
| Set_Next_Rep_Item |
| (First_Rep_Item (Derived_Type), First_Rep_Item (Parent_Type)); |
| end if; |
| end; |
| |
| else |
| Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type)); |
| end if; |
| |
| case Ekind (Parent_Type) is |
| when Numeric_Kind => |
| Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type); |
| |
| when Array_Kind => |
| Build_Derived_Array_Type (N, Parent_Type, Derived_Type); |
| |
| when E_Record_Type |
| | E_Record_Subtype |
| | Class_Wide_Kind => |
| Build_Derived_Record_Type |
| (N, Parent_Type, Derived_Type, Derive_Subps); |
| return; |
| |
| when Enumeration_Kind => |
| Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type); |
| |
| when Access_Kind => |
| Build_Derived_Access_Type (N, Parent_Type, Derived_Type); |
| |
| when Incomplete_Or_Private_Kind => |
| Build_Derived_Private_Type |
| (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps); |
| |
| -- For discriminated types, the derivation includes deriving |
| -- primitive operations. For others it is done below. |
| |
| if Is_Tagged_Type (Parent_Type) |
| or else Has_Discriminants (Parent_Type) |
| or else (Present (Full_View (Parent_Type)) |
| and then Has_Discriminants (Full_View (Parent_Type))) |
| then |
| return; |
| end if; |
| |
| when Concurrent_Kind => |
| Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type); |
| |
| when others => |
| raise Program_Error; |
| end case; |
| |
| if Etype (Derived_Type) = Any_Type then |
| return; |
| end if; |
| |
| -- Set delayed freeze and then derive subprograms, we need to do this |
| -- in this order so that derived subprograms inherit the derived freeze |
| -- if necessary. |
| |
| Set_Has_Delayed_Freeze (Derived_Type); |
| if Derive_Subps then |
| Derive_Subprograms (Parent_Type, Derived_Type); |
| end if; |
| |
| Set_Has_Primitive_Operations |
| (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type)); |
| end Build_Derived_Type; |
| |
| ----------------------- |
| -- Build_Discriminal -- |
| ----------------------- |
| |
| procedure Build_Discriminal (Discrim : Entity_Id) is |
| D_Minal : Entity_Id; |
| CR_Disc : Entity_Id; |
| |
| begin |
| -- A discriminal has the same name as the discriminant |
| |
| D_Minal := |
| Make_Defining_Identifier (Sloc (Discrim), |
| Chars => Chars (Discrim)); |
| |
| Set_Ekind (D_Minal, E_In_Parameter); |
| Set_Mechanism (D_Minal, Default_Mechanism); |
| Set_Etype (D_Minal, Etype (Discrim)); |
| |
| Set_Discriminal (Discrim, D_Minal); |
| Set_Discriminal_Link (D_Minal, Discrim); |
| |
| -- For task types, build at once the discriminants of the corresponding |
| -- record, which are needed if discriminants are used in entry defaults |
| -- and in family bounds. |
| |
| if Is_Concurrent_Type (Current_Scope) |
| or else Is_Limited_Type (Current_Scope) |
| then |
| CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim)); |
| |
| Set_Ekind (CR_Disc, E_In_Parameter); |
| Set_Mechanism (CR_Disc, Default_Mechanism); |
| Set_Etype (CR_Disc, Etype (Discrim)); |
| Set_Discriminal_Link (CR_Disc, Discrim); |
| Set_CR_Discriminant (Discrim, CR_Disc); |
| end if; |
| end Build_Discriminal; |
| |
| ------------------------------------ |
| -- Build_Discriminant_Constraints -- |
| ------------------------------------ |
| |
| function Build_Discriminant_Constraints |
| (T : Entity_Id; |
| Def : Node_Id; |
| Derived_Def : Boolean := False) return Elist_Id |
| is |
| C : constant Node_Id := Constraint (Def); |
| Nb_Discr : constant Nat := Number_Discriminants (T); |
| |
| Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty); |
| -- Saves the expression corresponding to a given discriminant in T |
| |
| function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat; |
| -- Return the Position number within array Discr_Expr of a discriminant |
| -- D within the discriminant list of the discriminated type T. |
| |
| ------------------ |
| -- Pos_Of_Discr -- |
| ------------------ |
| |
| function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is |
| Disc : Entity_Id; |
| |
| begin |
| Disc := First_Discriminant (T); |
| for J in Discr_Expr'Range loop |
| if Disc = D then |
| return J; |
| end if; |
| |
| Next_Discriminant (Disc); |
| end loop; |
| |
| -- Note: Since this function is called on discriminants that are |
| -- known to belong to the discriminated type, falling through the |
| -- loop with no match signals an internal compiler error. |
| |
| raise Program_Error; |
| end Pos_Of_Discr; |
| |
| -- Declarations local to Build_Discriminant_Constraints |
| |
| Discr : Entity_Id; |
| E : Entity_Id; |
| Elist : constant Elist_Id := New_Elmt_List; |
| |
| Constr : Node_Id; |
| Expr : Node_Id; |
| Id : Node_Id; |
| Position : Nat; |
| Found : Boolean; |
| |
| Discrim_Present : Boolean := False; |
| |
| -- Start of processing for Build_Discriminant_Constraints |
| |
| begin |
| -- The following loop will process positional associations only. |
| -- For a positional association, the (single) discriminant is |
| -- implicitly specified by position, in textual order (RM 3.7.2). |
| |
| Discr := First_Discriminant (T); |
| Constr := First (Constraints (C)); |
| |
| for D in Discr_Expr'Range loop |
| exit when Nkind (Constr) = N_Discriminant_Association; |
| |
| if No (Constr) then |
| Error_Msg_N ("too few discriminants given in constraint", C); |
| return New_Elmt_List; |
| |
| elsif Nkind (Constr) = N_Range |
| or else (Nkind (Constr) = N_Attribute_Reference |
| and then |
| Attribute_Name (Constr) = Name_Range) |
| then |
| Error_Msg_N |
| ("a range is not a valid discriminant constraint", Constr); |
| Discr_Expr (D) := Error; |
| |
| else |
| Analyze_And_Resolve (Constr, Base_Type (Etype (Discr))); |
| Discr_Expr (D) := Constr; |
| end if; |
| |
| Next_Discriminant (Discr); |
| Next (Constr); |
| end loop; |
| |
| if No (Discr) and then Present (Constr) then |
| Error_Msg_N ("too many discriminants given in constraint", Constr); |
| return New_Elmt_List; |
| end if; |
| |
| -- Named associations can be given in any order, but if both positional |
| -- and named associations are used in the same discriminant constraint, |
| -- then positional associations must occur first, at their normal |
| -- position. Hence once a named association is used, the rest of the |
| -- discriminant constraint must use only named associations. |
| |
| while Present (Constr) loop |
| |
| -- Positional association forbidden after a named association |
| |
| if Nkind (Constr) /= N_Discriminant_Association then |
| Error_Msg_N ("positional association follows named one", Constr); |
| return New_Elmt_List; |
| |
| -- Otherwise it is a named association |
| |
| else |
| -- E records the type of the discriminants in the named |
| -- association. All the discriminants specified in the same name |
| -- association must have the same type. |
| |
| E := Empty; |
| |
| -- Search the list of discriminants in T to see if the simple name |
| -- given in the constraint matches any of them. |
| |
| Id := First (Selector_Names (Constr)); |
| while Present (Id) loop |
| Found := False; |
| |
| -- If Original_Discriminant is present, we are processing a |
| -- generic instantiation and this is an instance node. We need |
| -- to find the name of the corresponding discriminant in the |
| -- actual record type T and not the name of the discriminant in |
| -- the generic formal. Example: |
| -- |
| -- generic |
| -- type G (D : int) is private; |
| -- package P is |
| -- subtype W is G (D => 1); |
| -- end package; |
| -- type Rec (X : int) is record ... end record; |
| -- package Q is new P (G => Rec); |
| -- |
| -- At the point of the instantiation, formal type G is Rec |
| -- and therefore when reanalyzing "subtype W is G (D => 1);" |
| -- which really looks like "subtype W is Rec (D => 1);" at |
| -- the point of instantiation, we want to find the discriminant |
| -- that corresponds to D in Rec, ie X. |
| |
| if Present (Original_Discriminant (Id)) then |
| Discr := Find_Corresponding_Discriminant (Id, T); |
| Found := True; |
| |
| else |
| Discr := First_Discriminant (T); |
| while Present (Discr) loop |
| if Chars (Discr) = Chars (Id) then |
| Found := True; |
| exit; |
| end if; |
| |
| Next_Discriminant (Discr); |
| end loop; |
| |
| if not Found then |
| Error_Msg_N ("& does not match any discriminant", Id); |
| return New_Elmt_List; |
| |
| -- The following is only useful for the benefit of generic |
| -- instances but it does not interfere with other |
| -- processing for the non-generic case so we do it in all |
| -- cases (for generics this statement is executed when |
| -- processing the generic definition, see comment at the |
| -- beginning of this if statement). |
| |
| else |
| Set_Original_Discriminant (Id, Discr); |
| end if; |
| end if; |
| |
| Position := Pos_Of_Discr (T, Discr); |
| |
| if Present (Discr_Expr (Position)) then |
| Error_Msg_N ("duplicate constraint for discriminant&", Id); |
| |
| else |
| -- Each discriminant specified in the same named association |
| -- must be associated with a separate copy of the |
| -- corresponding expression. |
| |
| if Present (Next (Id)) then |
| Expr := New_Copy_Tree (Expression (Constr)); |
| Set_Parent (Expr, Parent (Expression (Constr))); |
| else |
| Expr := Expression (Constr); |
| end if; |
| |
| Discr_Expr (Position) := Expr; |
| Analyze_And_Resolve (Expr, Base_Type (Etype (Discr))); |
| end if; |
| |
| -- A discriminant association with more than one discriminant |
| -- name is only allowed if the named discriminants are all of |
| -- the same type (RM 3.7.1(8)). |
| |
| if E = Empty then |
| E := Base_Type (Etype (Discr)); |
| |
| elsif Base_Type (Etype (Discr)) /= E then |
| Error_Msg_N |
| ("all discriminants in an association " & |
| "must have the same type", Id); |
| end if; |
| |
| Next (Id); |
| end loop; |
| end if; |
| |
| Next (Constr); |
| end loop; |
| |
| -- A discriminant constraint must provide exactly one value for each |
| -- discriminant of the type (RM 3.7.1(8)). |
| |
| for J in Discr_Expr'Range loop |
| if No (Discr_Expr (J)) then |
| Error_Msg_N ("too few discriminants given in constraint", C); |
| return New_Elmt_List; |
| end if; |
| end loop; |
| |
| -- Determine if there are discriminant expressions in the constraint |
| |
| for J in Discr_Expr'Range loop |
| if Denotes_Discriminant (Discr_Expr (J), Check_Protected => True) then |
| Discrim_Present := True; |
| end if; |
| end loop; |
| |
| -- Build an element list consisting of the expressions given in the |
| -- discriminant constraint and apply the appropriate checks. The list |
| -- is constructed after resolving any named discriminant associations |
| -- and therefore the expressions appear in the textual order of the |
| -- discriminants. |
| |
| Discr := First_Discriminant (T); |
| for J in Discr_Expr'Range loop |
| if Discr_Expr (J) /= Error then |
| |
| Append_Elmt (Discr_Expr (J), Elist); |
| |
| -- If any of the discriminant constraints is given by a |
| -- discriminant and we are in a derived type declaration we |
| -- have a discriminant renaming. Establish link between new |
| -- and old discriminant. |
| |
| if Denotes_Discriminant (Discr_Expr (J)) then |
| if Derived_Def then |
| Set_Corresponding_Discriminant |
| (Entity (Discr_Expr (J)), Discr); |
| end if; |
| |
| -- Force the evaluation of non-discriminant expressions. |
| -- If we have found a discriminant in the constraint 3.4(26) |
| -- and 3.8(18) demand that no range checks are performed are |
| -- after evaluation. If the constraint is for a component |
| -- definition that has a per-object constraint, expressions are |
| -- evaluated but not checked either. In all other cases perform |
| -- a range check. |
| |
| else |
| if Discrim_Present then |
| null; |
| |
| elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration |
| and then |
| Has_Per_Object_Constraint |
| (Defining_Identifier (Parent (Parent (Def)))) |
| then |
| null; |
| |
| elsif Is_Access_Type (Etype (Discr)) then |
| Apply_Constraint_Check (Discr_Expr (J), Etype (Discr)); |
| |
| else |
| Apply_Range_Check (Discr_Expr (J), Etype (Discr)); |
| end if; |
| |
| Force_Evaluation (Discr_Expr (J)); |
| end if; |
| |
| -- Check that the designated type of an access discriminant's |
| -- expression is not a class-wide type unless the discriminant's |
| -- designated type is also class-wide. |
| |
| if Ekind (Etype (Discr)) = E_Anonymous_Access_Type |
| and then not Is_Class_Wide_Type |
| (Designated_Type (Etype (Discr))) |
| and then Etype (Discr_Expr (J)) /= Any_Type |
| and then Is_Class_Wide_Type |
| (Designated_Type (Etype (Discr_Expr (J)))) |
| then |
| Wrong_Type (Discr_Expr (J), Etype (Discr)); |
| end if; |
| end if; |
| |
| Next_Discriminant (Discr); |
| end loop; |
| |
| return Elist; |
| end Build_Discriminant_Constraints; |
| |
| --------------------------------- |
| -- Build_Discriminated_Subtype -- |
| --------------------------------- |
| |
| procedure Build_Discriminated_Subtype |
| (T : Entity_Id; |
| Def_Id : Entity_Id; |
| Elist : Elist_Id; |
| Related_Nod : Node_Id; |
| For_Access : Boolean := False) |
| is |
| Has_Discrs : constant Boolean := Has_Discriminants (T); |
| Constrained : constant Boolean |
| := (Has_Discrs |
| and then not Is_Empty_Elmt_List (Elist) |
| and then not Is_Class_Wide_Type (T)) |
| or else Is_Constrained (T); |
| |
| begin |
| if Ekind (T) = E_Record_Type then |
| if For_Access then |
| Set_Ekind (Def_Id, E_Private_Subtype); |
| Set_Is_For_Access_Subtype (Def_Id, True); |
| else |
| Set_Ekind (Def_Id, E_Record_Subtype); |
| end if; |
| |
| elsif Ekind (T) = E_Task_Type then |
| Set_Ekind (Def_Id, E_Task_Subtype); |
| |
| elsif Ekind (T) = E_Protected_Type then |
| Set_Ekind (Def_Id, E_Protected_Subtype); |
| |
| elsif Is_Private_Type (T) then |
| Set_Ekind (Def_Id, Subtype_Kind (Ekind (T))); |
| |
| elsif Is_Class_Wide_Type (T) then |
| Set_Ekind (Def_Id, E_Class_Wide_Subtype); |
| |
| else |
| -- Incomplete type. attach subtype to list of dependents, to be |
| -- completed with full view of parent type, unless is it the |
| -- designated subtype of a record component within an init_proc. |
| -- This last case arises for a component of an access type whose |
| -- designated type is incomplete (e.g. a Taft Amendment type). |
| -- The designated subtype is within an inner scope, and needs no |
| -- elaboration, because only the access type is needed in the |
| -- initialization procedure. |
| |
| Set_Ekind (Def_Id, Ekind (T)); |
| |
| if For_Access and then Within_Init_Proc then |
| null; |
| else |
| Append_Elmt (Def_Id, Private_Dependents (T)); |
| end if; |
| end if; |
| |
| Set_Etype (Def_Id, T); |
| Init_Size_Align (Def_Id); |
| Set_Has_Discriminants (Def_Id, Has_Discrs); |
| Set_Is_Constrained (Def_Id, Constrained); |
| |
| Set_First_Entity (Def_Id, First_Entity (T)); |
| Set_Last_Entity (Def_Id, Last_Entity (T)); |
| Set_First_Rep_Item (Def_Id, First_Rep_Item (T)); |
| |
| if Is_Tagged_Type (T) then |
| Set_Is_Tagged_Type (Def_Id); |
| Make_Class_Wide_Type (Def_Id); |
| end if; |
| |
| Set_Stored_Constraint (Def_Id, No_Elist); |
| |
| if Has_Discrs then |
| Set_Discriminant_Constraint (Def_Id, Elist); |
| Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id); |
| end if; |
| |
| if Is_Tagged_Type (T) then |
| |
| -- Ada 2005 (AI-251): In case of concurrent types we inherit the |
| -- concurrent record type (which has the list of primitive |
| -- operations). |
| |
| if Ada_Version >= Ada_05 |
| and then Is_Concurrent_Type (T) |
| then |
| Set_Corresponding_Record_Type (Def_Id, |
| Corresponding_Record_Type (T)); |
| else |
| Set_Primitive_Operations (Def_Id, Primitive_Operations (T)); |
| end if; |
| |
| Set_Is_Abstract (Def_Id, Is_Abstract (T)); |
| end if; |
| |
| -- Subtypes introduced by component declarations do not need to be |
| -- marked as delayed, and do not get freeze nodes, because the semantics |
| -- verifies that the parents of the subtypes are frozen before the |
| -- enclosing record is frozen. |
| |
| if not Is_Type (Scope (Def_Id)) then |
| Set_Depends_On_Private (Def_Id, Depends_On_Private (T)); |
| |
| if Is_Private_Type (T) |
| and then Present (Full_View (T)) |
| then |
| Conditional_Delay (Def_Id, Full_View (T)); |
| else |
| Conditional_Delay (Def_Id, T); |
| end if; |
| end if; |
| |
| if Is_Record_Type (T) then |
| Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T)); |
| |
| if Has_Discrs |
| and then not Is_Empty_Elmt_List (Elist) |
| and then not For_Access |
| then |
| Create_Constrained_Components (Def_Id, Related_Nod, T, Elist); |
| elsif not For_Access then |
| Set_Cloned_Subtype (Def_Id, T); |
| end if; |
| end if; |
| |
| end Build_Discriminated_Subtype; |
| |
| ------------------------ |
| -- Build_Scalar_Bound -- |
| ------------------------ |
| |
| function Build_Scalar_Bound |
| (Bound : Node_Id; |
| Par_T : Entity_Id; |
| Der_T : Entity_Id) return Node_Id |
| is |
| New_Bound : Entity_Id; |
| |
| begin |
| -- Note: not clear why this is needed, how can the original bound |
| -- be unanalyzed at this point? and if it is, what business do we |
| -- have messing around with it? and why is the base type of the |
| -- parent type the right type for the resolution. It probably is |
| -- not! It is OK for the new bound we are creating, but not for |
| -- the old one??? Still if it never happens, no problem! |
| |
| Analyze_And_Resolve (Bound, Base_Type (Par_T)); |
| |
| if Nkind (Bound) = N_Integer_Literal |
| or else Nkind (Bound) = N_Real_Literal |
| then |
| New_Bound := New_Copy (Bound); |
| Set_Etype (New_Bound, Der_T); |
| Set_Analyzed (New_Bound); |
| |
| elsif Is_Entity_Name (Bound) then |
| New_Bound := OK_Convert_To (Der_T, New_Copy (Bound)); |
| |
| -- The following is almost certainly wrong. What business do we have |
| -- relocating a node (Bound) that is presumably still attached to |
| -- the tree elsewhere??? |
| |
| else |
| New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound)); |
| end if; |
| |
| Set_Etype (New_Bound, Der_T); |
| return New_Bound; |
| end Build_Scalar_Bound; |
| |
| -------------------------------- |
| -- Build_Underlying_Full_View -- |
| -------------------------------- |
| |
| procedure Build_Underlying_Full_View |
| (N : Node_Id; |
| Typ : Entity_Id; |
| Par : Entity_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| Subt : constant Entity_Id := |
| Make_Defining_Identifier |
| (Loc, New_External_Name (Chars (Typ), 'S')); |
| |
| Constr : Node_Id; |
| Indic : Node_Id; |
| C : Node_Id; |
| Id : Node_Id; |
| |
| procedure Set_Discriminant_Name (Id : Node_Id); |
| -- If the derived type has discriminants, they may rename discriminants |
| -- of the parent. When building the full view of the parent, we need to |
| -- recover the names of the original discriminants if the constraint is |
| -- given by named associations. |
| |
| --------------------------- |
| -- Set_Discriminant_Name -- |
| --------------------------- |
| |
| procedure Set_Discriminant_Name (Id : Node_Id) is |
| Disc : Entity_Id; |
| |
| begin |
| Set_Original_Discriminant (Id, Empty); |
| |
| if Has_Discriminants (Typ) then |
| Disc := First_Discriminant (Typ); |
| while Present (Disc) loop |
| if Chars (Disc) = Chars (Id) |
| and then Present (Corresponding_Discriminant (Disc)) |
| then |
| Set_Chars (Id, Chars (Corresponding_Discriminant (Disc))); |
| end if; |
| Next_Discriminant (Disc); |
| end loop; |
| end if; |
| end Set_Discriminant_Name; |
| |
| -- Start of processing for Build_Underlying_Full_View |
| |
| begin |
| if Nkind (N) = N_Full_Type_Declaration then |
| Constr := Constraint (Subtype_Indication (Type_Definition (N))); |
| |
| elsif Nkind (N) = N_Subtype_Declaration then |
| Constr := New_Copy_Tree (Constraint (Subtype_Indication (N))); |
| |
| elsif Nkind (N) = N_Component_Declaration then |
| Constr := |
| New_Copy_Tree |
| (Constraint (Subtype_Indication (Component_Definition (N)))); |
| |
| else |
| raise Program_Error; |
| end if; |
| |
| C := First (Constraints (Constr)); |
| while Present (C) loop |
| if Nkind (C) = N_Discriminant_Association then |
| Id := First (Selector_Names (C)); |
| while Present (Id) loop |
| Set_Discriminant_Name (Id); |
| Next (Id); |
| end loop; |
| end if; |
| |
| Next (C); |
| end loop; |
| |
| Indic := |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Subt, |
| Subtype_Indication => |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Reference_To (Par, Loc), |
| Constraint => New_Copy_Tree (Constr))); |
| |
| -- If this is a component subtype for an outer itype, it is not |
| -- a list member, so simply set the parent link for analysis: if |
| -- the enclosing type does not need to be in a declarative list, |
| -- neither do the components. |
| |
| if Is_List_Member (N) |
| and then Nkind (N) /= N_Component_Declaration |
| then |
| Insert_Before (N, Indic); |
| else |
| Set_Parent (Indic, Parent (N)); |
| end if; |
| |
| Analyze (Indic); |
| Set_Underlying_Full_View (Typ, Full_View (Subt)); |
| end Build_Underlying_Full_View; |
| |
| ------------------------------- |
| -- Check_Abstract_Overriding -- |
| ------------------------------- |
| |
| procedure Check_Abstract_Overriding (T : Entity_Id) is |
| Op_List : Elist_Id; |
| Elmt : Elmt_Id; |
| Subp : Entity_Id; |
| Alias_Subp : Entity_Id; |
| Type_Def : Node_Id; |
| |
| begin |
| Op_List := Primitive_Operations (T); |
| |
| -- Loop to check primitive operations |
| |
| Elmt := First_Elmt (Op_List); |
| while Present (Elmt) loop |
| Subp := Node (Elmt); |
| Alias_Subp := Alias (Subp); |
| |
| -- Inherited subprograms are identified by the fact that they do not |
| -- come from source, and the associated source location is the |
| -- location of the first subtype of the derived type. |
| |
| -- Special exception, do not complain about failure to override the |
| -- stream routines _Input and _Output, as well as the primitive |
| -- operations used in dispatching selects since we always provide |
| -- automatic overridings for these subprograms. |
| |
| if (Is_Abstract (Subp) |
| or else (Has_Controlling_Result (Subp) |
| and then Present (Alias_Subp) |
| and then not Comes_From_Source (Subp) |
| and then Sloc (Subp) = Sloc (First_Subtype (T)))) |
| and then not Is_TSS (Subp, TSS_Stream_Input) |
| and then not Is_TSS (Subp, TSS_Stream_Output) |
| and then not Is_Abstract (T) |
| and then Chars (Subp) /= Name_uDisp_Asynchronous_Select |
| and then Chars (Subp) /= Name_uDisp_Conditional_Select |
| and then Chars (Subp) /= Name_uDisp_Get_Prim_Op_Kind |
| and then Chars (Subp) /= Name_uDisp_Timed_Select |
| then |
| if Present (Alias_Subp) then |
| |
| -- Only perform the check for a derived subprogram when the |
| -- type has an explicit record extension. This avoids |
| -- incorrectly flagging abstract subprograms for the case of a |
| -- type without an extension derived from a formal type with a |
| -- tagged actual (can occur within a private part). |
| |
| -- Ada 2005 (AI-391): In the case of an inherited function with |
| -- a controlling result of the type, the rule does not apply if |
| -- the type is a null extension (unless the parent function |
| -- itself is abstract, in which case the function must still be |
| -- be overridden). The expander will generate an overriding |
| -- wrapper function calling the parent subprogram (see |
| -- Exp_Ch3.Make_Controlling_Wrapper_Functions). |
| |
| Type_Def := Type_Definition (Parent (T)); |
| if Nkind (Type_Def) = N_Derived_Type_Definition |
| and then Present (Record_Extension_Part (Type_Def)) |
| and then |
| (Ada_Version < Ada_05 |
| or else not Is_Null_Extension (T) |
| or else Ekind (Subp) = E_Procedure |
| or else not Has_Controlling_Result (Subp) |
| or else Is_Abstract (Alias_Subp) |
| or else Is_Access_Type (Etype (Subp))) |
| then |
| Error_Msg_NE |
| ("type must be declared abstract or & overridden", |
| T, Subp); |
| |
| -- Traverse the whole chain of aliased subprograms to |
| -- complete the error notification. This is especially |
| -- useful for traceability of the chain of entities when the |
| -- subprogram corresponds with an interface subprogram |
| -- (which might be defined in another package) |
| |
| if Present (Alias_Subp) then |
| declare |
| E : Entity_Id; |
| |
| begin |
| E := Subp; |
| while Present (Alias (E)) loop |
| Error_Msg_Sloc := Sloc (E); |
| Error_Msg_NE ("\& has been inherited #", T, Subp); |
| E := Alias (E); |
| end loop; |
| |
| Error_Msg_Sloc := Sloc (E); |
| Error_Msg_NE |
| ("\& has been inherited from subprogram #", T, Subp); |
| end; |
| end if; |
| |
| -- Ada 2005 (AI-345): Protected or task type implementing |
| -- abstract interfaces. |
| |
| elsif Is_Concurrent_Record_Type (T) |
| and then Present (Abstract_Interfaces (T)) |
| then |
| Error_Msg_NE |
| ("interface subprogram & must be overridden", |
| T, Subp); |
| end if; |
| else |
| Error_Msg_NE |
| ("abstract subprogram not allowed for type&", |
| Subp, T); |
| Error_Msg_NE |
| ("nonabstract type has abstract subprogram&", |
| T, Subp); |
| end if; |
| end if; |
| |
| Next_Elmt (Elmt); |
| end loop; |
| end Check_Abstract_Overriding; |
| |
| ------------------------------------------------ |
| -- Check_Access_Discriminant_Requires_Limited -- |
| ------------------------------------------------ |
| |
| procedure Check_Access_Discriminant_Requires_Limited |
| (D : Node_Id; |
| Loc : Node_Id) |
| is |
| begin |
| -- A discriminant_specification for an access discriminant shall appear |
| -- only in the declaration for a task or protected type, or for a type |
| -- with the reserved word 'limited' in its definition or in one of its |
| -- ancestors. (RM 3.7(10)) |
| |
| if Nkind (Discriminant_Type (D)) = N_Access_Definition |
| and then not Is_Concurrent_Type (Current_Scope) |
| and then not Is_Concurrent_Record_Type (Current_Scope) |
| and then not Is_Limited_Record (Current_Scope) |
| and then Ekind (Current_Scope) /= E_Limited_Private_Type |
| then |
| Error_Msg_N |
| ("access discriminants allowed only for limited types", Loc); |
| end if; |
| end Check_Access_Discriminant_Requires_Limited; |
| |
| ----------------------------------- |
| -- Check_Aliased_Component_Types -- |
| ----------------------------------- |
| |
| procedure Check_Aliased_Component_Types (T : Entity_Id) is |
| C : Entity_Id; |
| |
| begin |
| -- ??? Also need to check components of record extensions, but not |
| -- components of protected types (which are always limited). |
| |
| -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such |
| -- types to be unconstrained. This is safe because it is illegal to |
| -- create access subtypes to such types with explicit discriminant |
| -- constraints. |
| |
| if not Is_Limited_Type (T) then |
| if Ekind (T) = E_Record_Type then |
| C := First_Component (T); |
| while Present (C) loop |
| if Is_Aliased (C) |
| and then Has_Discriminants (Etype (C)) |
| and then not Is_Constrained (Etype (C)) |
| and then not In_Instance_Body |
| and then Ada_Version < Ada_05 |
| then |
| Error_Msg_N |
| ("aliased component must be constrained ('R'M 3.6(11))", |
| C); |
| end if; |
| |
| Next_Component (C); |
| end loop; |
| |
| elsif Ekind (T) = E_Array_Type then |
| if Has_Aliased_Components (T) |
| and then Has_Discriminants (Component_Type (T)) |
| and then not Is_Constrained (Component_Type (T)) |
| and then not In_Instance_Body |
| and then Ada_Version < Ada_05 |
| then |
| Error_Msg_N |
| ("aliased component type must be constrained ('R'M 3.6(11))", |
| T); |
| end if; |
| end if; |
| end if; |
| end Check_Aliased_Component_Types; |
| |
| ---------------------- |
| -- Check_Completion -- |
| ---------------------- |
| |
| procedure Check_Completion (Body_Id : Node_Id := Empty) is |
| E : Entity_Id; |
| |
| procedure Post_Error; |
| -- Post error message for lack of completion for entity E |
| |
| ---------------- |
| -- Post_Error -- |
| ---------------- |
| |
| procedure Post_Error is |
| begin |
| if not Comes_From_Source (E) then |
| |
| if Ekind (E) = E_Task_Type |
| or else Ekind (E) = E_Protected_Type |
| then |
| -- It may be an anonymous protected type created for a |
| -- single variable. Post error on variable, if present. |
| |
| declare |
| Var : Entity_Id; |
| |
| begin |
| Var := First_Entity (Current_Scope); |
| while Present (Var) loop |
| exit when Etype (Var) = E |
| and then Comes_From_Source (Var); |
| |
| Next_Entity (Var); |
| end loop; |
| |
| if Present (Var) then |
| E := Var; |
| end if; |
| end; |
| end if; |
| end if; |
| |
| -- If a generated entity has no completion, then either previous |
| -- semantic errors have disabled the expansion phase, or else we had |
| -- missing subunits, or else we are compiling without expan- sion, |
| -- or else something is very wrong. |
| |
| if not Comes_From_Source (E) then |
| pragma Assert |
| (Serious_Errors_Detected > 0 |
| or else Configurable_Run_Time_Violations > 0 |
| or else Subunits_Missing |
| or else not Expander_Active); |
| return; |
| |
| -- Here for source entity |
| |
| else |
| -- Here if no body to post the error message, so we post the error |
| -- on the declaration that has no completion. This is not really |
| -- the right place to post it, think about this later ??? |
| |
| if No (Body_Id) then |
| if Is_Type (E) then |
| Error_Msg_NE |
| ("missing full declaration for }", Parent (E), E); |
| else |
| Error_Msg_NE |
| ("missing body for &", Parent (E), E); |
| end if; |
| |
| -- Package body has no completion for a declaration that appears |
| -- in the corresponding spec. Post error on the body, with a |
| -- reference to the non-completed declaration. |
| |
| else |
| Error_Msg_Sloc := Sloc (E); |
| |
| if Is_Type (E) then |
| Error_Msg_NE |
| ("missing full declaration for }!", Body_Id, E); |
| |
| elsif Is_Overloadable (E) |
| and then Current_Entity_In_Scope (E) /= E |
| then |
| -- It may be that the completion is mistyped and appears |
| -- as a distinct overloading of the entity. |
| |
| declare |
| Candidate : constant Entity_Id := |
| Current_Entity_In_Scope (E); |
| Decl : constant Node_Id := |
| Unit_Declaration_Node (Candidate); |
| |
| begin |
| if Is_Overloadable (Candidate) |
| and then Ekind (Candidate) = Ekind (E) |
| and then Nkind (Decl) = N_Subprogram_Body |
| and then Acts_As_Spec (Decl) |
| then |
| Check_Type_Conformant (Candidate, E); |
| |
| else |
| Error_Msg_NE ("missing body for & declared#!", |
| Body_Id, E); |
| end if; |
| end; |
| else |
| Error_Msg_NE ("missing body for & declared#!", |
| Body_Id, E); |
| end if; |
| end if; |
| end if; |
| end Post_Error; |
| |
| -- Start processing for Check_Completion |
| |
| begin |
| E := First_Entity (Current_Scope); |
| while Present (E) loop |
| if Is_Intrinsic_Subprogram (E) then |
| null; |
| |
| -- The following situation requires special handling: a child |
| -- unit that appears in the context clause of the body of its |
| -- parent: |
| |
| -- procedure Parent.Child (...); |
| |
| -- with Parent.Child; |
| -- package body Parent is |
| |
| -- Here Parent.Child appears as a local entity, but should not |
| -- be flagged as requiring completion, because it is a |
| -- compilation unit. |
| |
| elsif Ekind (E) = E_Function |
| or else Ekind (E) = E_Procedure |
| or else Ekind (E) = E_Generic_Function |
| or else Ekind (E) = E_Generic_Procedure |
| then |
| if not Has_Completion (E) |
| and then not Is_Abstract (E) |
| and then Nkind (Parent (Unit_Declaration_Node (E))) /= |
| N_Compilation_Unit |
| and then Chars (E) /= Name_uSize |
| then |
| Post_Error; |
| end if; |
| |
| elsif Is_Entry (E) then |
| if not Has_Completion (E) and then |
| (Ekind (Scope (E)) = E_Protected_Object |
| or else Ekind (Scope (E)) = E_Protected_Type) |
| then |
| Post_Error; |
| end if; |
| |
| elsif Is_Package_Or_Generic_Package (E) then |
| if Unit_Requires_Body (E) then |
| if not Has_Completion (E) |
| and then Nkind (Parent (Unit_Declaration_Node (E))) /= |
| N_Compilation_Unit |
| then |
| Post_Error; |
| end if; |
| |
| elsif not Is_Child_Unit (E) then |
| May_Need_Implicit_Body (E); |
| end if; |
| |
| elsif Ekind (E) = E_Incomplete_Type |
| and then No (Underlying_Type (E)) |
| then |
| Post_Error; |
| |
| elsif (Ekind (E) = E_Task_Type or else |
| Ekind (E) = E_Protected_Type) |
| and then not Has_Completion (E) |
| then |
| Post_Error; |
| |
| -- A single task declared in the current scope is a constant, verify |
| -- that the body of its anonymous type is in the same scope. If the |
| -- task is defined elsewhere, this may be a renaming declaration for |
| -- which no completion is needed. |
| |
| elsif Ekind (E) = E_Constant |
| and then Ekind (Etype (E)) = E_Task_Type |
| and then not Has_Completion (Etype (E)) |
| and then Scope (Etype (E)) = Current_Scope |
| then |
| Post_Error; |
| |
| elsif Ekind (E) = E_Protected_Object |
| and then not Has_Completion (Etype (E)) |
| then |
| Post_Error; |
| |
| elsif Ekind (E) = E_Record_Type then |
| if Is_Tagged_Type (E) then |
| Check_Abstract_Overriding (E); |
| end if; |
| |
| Check_Aliased_Component_Types (E); |
| |
| elsif Ekind (E) = E_Array_Type then |
| Check_Aliased_Component_Types (E); |
| |
| end if; |
| |
| Next_Entity (E); |
| end loop; |
| end Check_Completion; |
| |
| ---------------------------- |
| -- Check_Delta_Expression -- |
| ---------------------------- |
| |
| procedure Check_Delta_Expression (E : Node_Id) is |
| begin |
| if not (Is_Real_Type (Etype (E))) then |
| Wrong_Type (E, Any_Real); |
| |
| elsif not Is_OK_Static_Expression (E) then |
| Flag_Non_Static_Expr |
| ("non-static expression used for delta value!", E); |
| |
| elsif not UR_Is_Positive (Expr_Value_R (E)) then |
| Error_Msg_N ("delta expression must be positive", E); |
| |
| else |
| return; |
| end if; |
| |
| -- If any of above errors occurred, then replace the incorrect |
| -- expression by the real 0.1, which should prevent further errors. |
| |
| Rewrite (E, |
| Make_Real_Literal (Sloc (E), Ureal_Tenth)); |
| Analyze_And_Resolve (E, Standard_Float); |
| end Check_Delta_Expression; |
| |
| ----------------------------- |
| -- Check_Digits_Expression -- |
| ----------------------------- |
| |
| procedure Check_Digits_Expression (E : Node_Id) is |
| begin |
| if not (Is_Integer_Type (Etype (E))) then |
| Wrong_Type (E, Any_Integer); |
| |
| elsif not Is_OK_Static_Expression (E) then |
| Flag_Non_Static_Expr |
| ("non-static expression used for digits value!", E); |
| |
| elsif Expr_Value (E) <= 0 then |
| Error_Msg_N ("digits value must be greater than zero", E); |
| |
| else |
| return; |
| end if; |
| |
| -- If any of above errors occurred, then replace the incorrect |
| -- expression by the integer 1, which should prevent further errors. |
| |
| Rewrite (E, Make_Integer_Literal (Sloc (E), 1)); |
| Analyze_And_Resolve (E, Standard_Integer); |
| |
| end Check_Digits_Expression; |
| |
| -------------------------- |
| -- Check_Initialization -- |
| -------------------------- |
| |
| procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is |
| begin |
| if (Is_Limited_Type (T) |
| or else Is_Limited_Composite (T)) |
| and then not In_Instance |
| and then not In_Inlined_Body |
| then |
| -- Ada 2005 (AI-287): Relax the strictness of the front-end in |
| -- case of limited aggregates and extension aggregates. |
| |
| if Ada_Version >= Ada_05 |
| and then (Nkind (Exp) = N_Aggregate |
| or else Nkind (Exp) = N_Extension_Aggregate) |
| then |
| null; |
| else |
| Error_Msg_N |
| ("cannot initialize entities of limited type", Exp); |
| Explain_Limited_Type (T, Exp); |
| end if; |
| end if; |
| end Check_Initialization; |
| |
| ------------------------------------ |
| -- Check_Or_Process_Discriminants -- |
| ------------------------------------ |
| |
| -- If an incomplete or private type declaration was already given for the |
| -- type, the discriminants may have already been processed if they were |
| -- present on the incomplete declaration. In this case a full conformance |
| -- check is performed otherwise just process them. |
| |
| procedure Check_Or_Process_Discriminants |
| (N : Node_Id; |
| T : Entity_Id; |
| Prev : Entity_Id := Empty) |
| is |
| begin |
| if Has_Discriminants (T) then |
| |
| -- Make the discriminants visible to component declarations |
| |
| declare |
| D : Entity_Id; |
| Prev : Entity_Id; |
| |
| begin |
| D := First_Discriminant (T); |
| while Present (D) loop |
| Prev := Current_Entity (D); |
| Set_Current_Entity (D); |
| Set_Is_Immediately_Visible (D); |
| Set_Homonym (D, Prev); |
| |
| -- Ada 2005 (AI-230): Access discriminant allowed in |
| -- non-limited record types. |
| |
| if Ada_Version < Ada_05 then |
| |
| -- This restriction gets applied to the full type here. It |
| -- has already been applied earlier to the partial view. |
| |
| Check_Access_Discriminant_Requires_Limited (Parent (D), N); |
| end if; |
| |
| Next_Discriminant (D); |
| end loop; |
| end; |
| |
| elsif Present (Discriminant_Specifications (N)) then |
| Process_Discriminants (N, Prev); |
| end if; |
| end Check_Or_Process_Discriminants; |
| |
| ---------------------- |
| -- Check_Real_Bound -- |
| ---------------------- |
| |
| procedure Check_Real_Bound (Bound : Node_Id) is |
| begin |
| if not Is_Real_Type (Etype (Bound)) then |
| Error_Msg_N |
| ("bound in real type definition must be of real type", Bound); |
| |
| elsif not Is_OK_Static_Expression (Bound) then |
| Flag_Non_Static_Expr |
| ("non-static expression used for real type bound!", Bound); |
| |
| else |
| return; |
| end if; |
| |
| Rewrite |
| (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0)); |
| Analyze (Bound); |
| Resolve (Bound, Standard_Float); |
| end Check_Real_Bound; |
| |
| ------------------------ |
| -- Collect_Interfaces -- |
| ------------------------ |
| |
| procedure Collect_Interfaces (N : Node_Id; Derived_Type : Entity_Id) is |
| Intf : Node_Id; |
| |
| procedure Add_Interface (Iface : Entity_Id); |
| -- Add one interface |
| |
| ------------------- |
| -- Add_Interface -- |
| ------------------- |
| |
| procedure Add_Interface (Iface : Entity_Id) is |
| Elmt : Elmt_Id; |
| |
| begin |
| Elmt := First_Elmt (Abstract_Interfaces (Derived_Type)); |
| while Present (Elmt) and then Node (Elmt) /= Iface loop |
| Next_Elmt (Elmt); |
| end loop; |
| |
| if No (Elmt) then |
| Append_Elmt (Node => Iface, |
| To => Abstract_Interfaces (Derived_Type)); |
| end if; |
| end Add_Interface; |
| |
| -- Start of processing for Collect_Interfaces |
| |
| begin |
| pragma Assert (False |
| or else Nkind (N) = N_Derived_Type_Definition |
| or else Nkind (N) = N_Record_Definition |
| or else Nkind (N) = N_Private_Extension_Declaration); |
| |
| -- Traverse the graph of ancestor interfaces |
| |
| if Is_Non_Empty_List (Interface_List (N)) then |
| Intf := First (Interface_List (N)); |
| while Present (Intf) loop |
| |
| -- Protect against wrong uses. For example: |
| -- type I is interface; |
| -- type O is tagged null record; |
| -- type Wrong is new I and O with null record; -- ERROR |
| |
| if Is_Interface (Etype (Intf)) then |
| |
| -- Do not add the interface when the derived type already |
| -- implements this interface |
| |
| if not Interface_Present_In_Ancestor (Derived_Type, |
| Etype (Intf)) |
| then |
| Collect_Interfaces |
| (Type_Definition (Parent (Etype (Intf))), |
| Derived_Type); |
| Add_Interface (Etype (Intf)); |
| end if; |
| end if; |
| |
| Next (Intf); |
| end loop; |
| end if; |
| end Collect_Interfaces; |
| |
| ------------------------------ |
| -- Complete_Private_Subtype -- |
| ------------------------------ |
| |
| procedure Complete_Private_Subtype |
| (Priv : Entity_Id; |
| Full : Entity_Id; |
| Full_Base : Entity_Id; |
| Related_Nod : Node_Id) |
| is |
| Save_Next_Entity : Entity_Id; |
| Save_Homonym : Entity_Id; |
| |
| begin |
| -- Set semantic attributes for (implicit) private subtype completion. |
| -- If the full type has no discriminants, then it is a copy of the full |
| -- view of the base. Otherwise, it is a subtype of the base with a |
| -- possible discriminant constraint. Save and restore the original |
| -- Next_Entity field of full to ensure that the calls to Copy_Node |
| -- do not corrupt the entity chain. |
| |
| -- Note that the type of the full view is the same entity as the type of |
| -- the partial view. In this fashion, the subtype has access to the |
| -- correct view of the parent. |
| |
| Save_Next_Entity := Next_Entity (Full); |
| Save_Homonym := Homonym (Priv); |
| |
| case Ekind (Full_Base) is |
| when E_Record_Type | |
| E_Record_Subtype | |
| Class_Wide_Kind | |
| Private_Kind | |
| Task_Kind | |
| Protected_Kind => |
| Copy_Node (Priv, Full); |
| |
| Set_Has_Discriminants (Full, Has_Discriminants (Full_Base)); |
| Set_First_Entity (Full, First_Entity (Full_Base)); |
| Set_Last_Entity (Full, Last_Entity (Full_Base)); |
| |
| when others => |
| Copy_Node (Full_Base, Full); |
| Set_Chars (Full, Chars (Priv)); |
| Conditional_Delay (Full, Priv); |
| Set_Sloc (Full, Sloc (Priv)); |
| end case; |
| |
| Set_Next_Entity (Full, Save_Next_Entity); |
| Set_Homonym (Full, Save_Homonym); |
| Set_Associated_Node_For_Itype (Full, Related_Nod); |
| |
| -- Set common attributes for all subtypes |
| |
| Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base))); |
| |
| -- The Etype of the full view is inconsistent. Gigi needs to see the |
| -- structural full view, which is what the current scheme gives: |
| -- the Etype of the full view is the etype of the full base. However, |
| -- if the full base is a derived type, the full view then looks like |
| -- a subtype of the parent, not a subtype of the full base. If instead |
| -- we write: |
| |
| -- Set_Etype (Full, Full_Base); |
| |
| -- then we get inconsistencies in the front-end (confusion between |
| -- views). Several outstanding bugs are related to this ??? |
| |
| Set_Is_First_Subtype (Full, False); |
| Set_Scope (Full, Scope (Priv)); |
| Set_Size_Info (Full, Full_Base); |
| Set_RM_Size (Full, RM_Size (Full_Base)); |
| Set_Is_Itype (Full); |
| |
| -- A subtype of a private-type-without-discriminants, whose full-view |
| -- has discriminants with default expressions, is not constrained! |
| |
| if not Has_Discriminants (Priv) then |
| Set_Is_Constrained (Full, Is_Constrained (Full_Base)); |
| |
| if Has_Discriminants (Full_Base) then |
| Set_Discriminant_Constraint |
| (Full, Discriminant_Constraint (Full_Base)); |
| |
| -- The partial view may have been indefinite, the full view |
| -- might not be. |
| |
| Set_Has_Unknown_Discriminants |
| (Full, Has_Unknown_Discriminants (Full_Base)); |
| end if; |
| end if; |
| |
| Set_First_Rep_Item (Full, First_Rep_Item (Full_Base)); |
| Set_Depends_On_Private (Full, Has_Private_Component (Full)); |
| |
| -- Freeze the private subtype entity if its parent is delayed, and not |
| -- already frozen. We skip this processing if the type is an anonymous |
| -- subtype of a record component, or is the corresponding record of a |
| -- protected type, since ??? |
| |
| if not Is_Type (Scope (Full)) then |
| Set_Has_Delayed_Freeze (Full, |
| Has_Delayed_Freeze (Full_Base) |
| and then (not Is_Frozen (Full_Base))); |
| end if; |
| |
| Set_Freeze_Node (Full, Empty); |
| Set_Is_Frozen (Full, False); |
| Set_Full_View (Priv, Full); |
| |
| if Has_Discriminants (Full) then |
| Set_Stored_Constraint_From_Discriminant_Constraint (Full); |
| Set_Stored_Constraint (Priv, Stored_Constraint (Full)); |
| |
| if Has_Unknown_Discriminants (Full) then |
| Set_Discriminant_Constraint (Full, No_Elist); |
| end if; |
| end if; |
| |
| if Ekind (Full_Base) = E_Record_Type |
| and then Has_Discriminants (Full_Base) |
| and then Has_Discriminants (Priv) -- might not, if errors |
| and then not Has_Unknown_Discriminants (Priv) |
| and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv)) |
| then |
| Create_Constrained_Components |
| (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv)); |
| |
| -- If the full base is itself derived from private, build a congruent |
| -- subtype of its underlying type, for use by the back end. For a |
| -- constrained record component, the declaration cannot be placed on |
| -- the component list, but it must nevertheless be built an analyzed, to |
| -- supply enough information for Gigi to compute the size of component. |
| |
| elsif Ekind (Full_Base) in Private_Kind |
| and then Is_Derived_Type (Full_Base) |
| and then Has_Discriminants (Full_Base) |
| and then (Ekind (Current_Scope) /= E_Record_Subtype) |
| then |
| if not Is_Itype (Priv) |
| and then |
| Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication |
| then |
| Build_Underlying_Full_View |
| (Parent (Priv), Full, Etype (Full_Base)); |
| |
| elsif Nkind (Related_Nod) = N_Component_Declaration then |
| Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base)); |
| end if; |
| |
| elsif Is_Record_Type (Full_Base) then |
| |
| -- Show Full is simply a renaming of Full_Base |
| |
| Set_Cloned_Subtype (Full, Full_Base); |
| end if; |
| |
| -- It is unsafe to share to bounds of a scalar type, because the Itype |
| -- is elaborated on demand, and if a bound is non-static then different |
| -- orders of elaboration in different units will lead to different |
| -- external symbols. |
| |
| if Is_Scalar_Type (Full_Base) then |
| Set_Scalar_Range (Full, |
| Make_Range (Sloc (Related_Nod), |
| Low_Bound => |
| Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)), |
| High_Bound => |
| Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base)))); |
| |
| -- This completion inherits the bounds of the full parent, but if |
| -- the parent is an unconstrained floating point type, so is the |
| -- completion. |
| |
| if Is_Floating_Point_Type (Full_Base) then |
| Set_Includes_Infinities |
| (Scalar_Range (Full), Has_Infinities (Full_Base)); |
| end if; |
| end if; |
| |
| -- ??? It seems that a lot of fields are missing that should be copied |
| -- from Full_Base to Full. Here are some that are introduced in a |
| -- non-disruptive way but a cleanup is necessary. |
| |
| if Is_Tagged_Type (Full_Base) then |
| Set_Is_Tagged_Type (Full); |
| Set_Primitive_Operations (Full, Primitive_Operations (Full_Base)); |
| Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base)); |
| |
| -- If this is a subtype of a protected or task type, constrain its |
| -- corresponding record, unless this is a subtype without constraints, |
| -- i.e. a simple renaming as with an actual subtype in an instance. |
| |
| elsif Is_Concurrent_Type (Full_Base) then |
| if Has_Discriminants (Full) |
| and then Present (Corresponding_Record_Type (Full_Base)) |
| and then |
| not Is_Empty_Elmt_List (Discriminant_Constraint (Full)) |
| then |
| Set_Corresponding_Record_Type (Full, |
| Constrain_Corresponding_Record |
| (Full, Corresponding_Record_Type (Full_Base), |
| Related_Nod, Full_Base)); |
| |
| else |
| Set_Corresponding_Record_Type (Full, |
| Corresponding_Record_Type (Full_Base)); |
| end if; |
| end if; |
| end Complete_Private_Subtype; |
| |
| ------------------------------------- |
| -- Complete_Subprograms_Derivation -- |
| ------------------------------------- |
| |
| procedure Complete_Subprograms_Derivation |
| (Partial_View : Entity_Id; |
| Derived_Type : Entity_Id) |
| is |
| Result : constant Elist_Id := New_Elmt_List; |
| Elmt_P : Elmt_Id; |
| Elmt_D : Elmt_Id; |
| Found : Boolean; |
| Prim_Op : Entity_Id; |
| E : Entity_Id; |
| |
| begin |
| -- Handle the case in which the full-view is a transitive |
| -- derivation of the ancestor of the partial view. |
| |
| -- type I is interface; |
| -- type T is new I with ... |
| |
| -- package H is |
| -- type DT is new I with private; |
| -- private |
| -- type DT is new T with ... |
| -- end; |
| |
| if Etype (Partial_View) /= Etype (Derived_Type) |
| and then Is_Interface (Etype (Partial_View)) |
| and then Is_Ancestor (Etype (Partial_View), Etype (Derived_Type)) |
| then |
| return; |
| end if; |
| |
| if Is_Tagged_Type (Partial_View) then |
| Elmt_P := First_Elmt (Primitive_Operations (Partial_View)); |
| else |
| Elmt_P := No_Elmt; |
| end if; |
| |
| -- Inherit primitives declared with the partial-view |
| |
| while Present (Elmt_P) loop |
| Prim_Op := Node (Elmt_P); |
| Found := False; |
| Elmt_D := First_Elmt (Primitive_Operations (Derived_Type)); |
| while Present (Elmt_D) loop |
| if Node (Elmt_D) = Prim_Op then |
| Found := True; |
| exit; |
| end if; |
| |
| Next_Elmt (Elmt_D); |
| end loop; |
| |
| if not Found then |
| Append_Elmt (Prim_Op, Result); |
| |
| -- Search for entries associated with abstract interfaces that |
| -- have been covered by this primitive |
| |
| Elmt_D := First_Elmt (Primitive_Operations (Derived_Type)); |
| while Present (Elmt_D) loop |
| E := Node (Elmt_D); |
| |
| if Chars (E) = Chars (Prim_Op) |
| and then Is_Abstract (E) |
| and then Present (Alias (E)) |
| and then Present (DTC_Entity (Alias (E))) |
| and then Is_Interface (Scope (DTC_Entity (Alias (E)))) |
| then |
| Remove_Elmt (Primitive_Operations (Derived_Type), Elmt_D); |
| end if; |
| |
| Next_Elmt (Elmt_D); |
| end loop; |
| end if; |
| |
| Next_Elmt (Elmt_P); |
| end loop; |
| |
| -- Append the entities of the full-view to the list of primitives |
| -- of derived_type. |
| |
| Elmt_D := First_Elmt (Result); |
| while Present (Elmt_D) loop |
| Append_Elmt (Node (Elmt_D), Primitive_Operations (Derived_Type)); |
| Next_Elmt (Elmt_D); |
| end loop; |
| end Complete_Subprograms_Derivation; |
| |
| ---------------------------- |
| -- Constant_Redeclaration -- |
| ---------------------------- |
| |
| procedure Constant_Redeclaration |
| (Id : Entity_Id; |
| N : Node_Id; |
| T : out Entity_Id) |
| is |
| Prev : constant Entity_Id := Current_Entity_In_Scope (Id); |
| Obj_Def : constant Node_Id := Object_Definition (N); |
| New_T : Entity_Id; |
| |
| procedure Check_Possible_Deferred_Completion |
| (Prev_Id : Entity_Id; |
| Prev_Obj_Def : Node_Id; |
| Curr_Obj_Def : Node_Id); |
| -- Determine whether the two object definitions describe the partial |
| -- and the full view of a constrained deferred constant. Generate |
| -- a subtype for the full view and verify that it statically matches |
| -- the subtype of the partial view. |
| |
| procedure Check_Recursive_Declaration (Typ : Entity_Id); |
| -- If deferred constant is an access type initialized with an allocator, |
| -- check whether there is an illegal recursion in the definition, |
| -- through a default value of some record subcomponent. This is normally |
| -- detected when generating init procs, but requires this additional |
| -- mechanism when expansion is disabled. |
| |
| ---------------------------------------- |
| -- Check_Possible_Deferred_Completion -- |
| ---------------------------------------- |
| |
| procedure Check_Possible_Deferred_Completion |
| (Prev_Id : Entity_Id; |
| Prev_Obj_Def : Node_Id; |
| Curr_Obj_Def : Node_Id) |
| is |
| begin |
| if Nkind (Prev_Obj_Def) = N_Subtype_Indication |
| and then Present (Constraint (Prev_Obj_Def)) |
| and then Nkind (Curr_Obj_Def) = N_Subtype_Indication |
| and then Present (Constraint (Curr_Obj_Def)) |
| then |
| declare |
| Loc : constant Source_Ptr := Sloc (N); |
| Def_Id : constant Entity_Id := |
| Make_Defining_Identifier (Loc, |
| New_Internal_Name ('S')); |
| Decl : constant Node_Id := |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => |
| Def_Id, |
| Subtype_Indication => |
| Relocate_Node (Curr_Obj_Def)); |
| |
| begin |
| Insert_Before_And_Analyze (N, Decl); |
| Set_Etype (Id, Def_Id); |
| |
| if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then |
| Error_Msg_Sloc := Sloc (Prev_Id); |
| Error_Msg_N ("subtype does not statically match deferred " & |
| "declaration#", N); |
| end if; |
| end; |
| end if; |
| end Check_Possible_Deferred_Completion; |
| |
| --------------------------------- |
| -- Check_Recursive_Declaration -- |
| --------------------------------- |
| |
| procedure Check_Recursive_Declaration (Typ : Entity_Id) is |
| Comp : Entity_Id; |
| |
| begin |
| if Is_Record_Type (Typ) then |
| Comp := First_Component (Typ); |
| while Present (Comp) loop |
| if Comes_From_Source (Comp) then |
| if Present (Expression (Parent (Comp))) |
| and then Is_Entity_Name (Expression (Parent (Comp))) |
| and then Entity (Expression (Parent (Comp))) = Prev |
| then |
| Error_Msg_Sloc := Sloc (Parent (Comp)); |
| Error_Msg_NE |
| ("illegal circularity with declaration for&#", |
| N, Comp); |
| return; |
| |
| elsif Is_Record_Type (Etype (Comp)) then |
| Check_Recursive_Declaration (Etype (Comp)); |
| end if; |
| end if; |
| |
| Next_Component (Comp); |
| end loop; |
| end if; |
| end Check_Recursive_Declaration; |
| |
| -- Start of processing for Constant_Redeclaration |
| |
| begin |
| if Nkind (Parent (Prev)) = N_Object_Declaration then |
| if Nkind (Object_Definition |
| (Parent (Prev))) = N_Subtype_Indication |
| then |
| -- Find type of new declaration. The constraints of the two |
| -- views must match statically, but there is no point in |
| -- creating an itype for the full view. |
| |
| if Nkind (Obj_Def) = N_Subtype_Indication then |
| Find_Type (Subtype_Mark (Obj_Def)); |
| New_T := Entity (Subtype_Mark (Obj_Def)); |
| |
| else |
| Find_Type (Obj_Def); |
| New_T := Entity (Obj_Def); |
| end if; |
| |
| T := Etype (Prev); |
| |
| else |
| -- The full view may impose a constraint, even if the partial |
| -- view does not, so construct the subtype. |
| |
| New_T := Find_Type_Of_Object (Obj_Def, N); |
| T := New_T; |
| end if; |
| |
| else |
| -- Current declaration is illegal, diagnosed below in Enter_Name |
| |
| T := Empty; |
| New_T := Any_Type; |
| end if; |
| |
| -- If previous full declaration exists, or if a homograph is present, |
| -- let Enter_Name handle it, either with an error, or with the removal |
| -- of an overridden implicit subprogram. |
| |
| if Ekind (Prev) /= E_Constant |
| or else Present (Expression (Parent (Prev))) |
| or else Present (Full_View (Prev)) |
| then |
| Enter_Name (Id); |
| |
| -- Verify that types of both declarations match, or else that both types |
| -- are anonymous access types whose designated subtypes statically match |
| -- (as allowed in Ada 2005 by AI-385). |
| |
| elsif Base_Type (Etype (Prev)) /= Base_Type (New_T) |
| and then |
| (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type |
| or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type |
| or else not Subtypes_Statically_Match |
| (Designated_Type (Etype (Prev)), |
| Designated_Type (Etype (New_T)))) |
| then |
| Error_Msg_Sloc := Sloc (Prev); |
| Error_Msg_N ("type does not match declaration#", N); |
| Set_Full_View (Prev, Id); |
| Set_Etype (Id, Any_Type); |
| |
| -- If so, process the full constant declaration |
| |
| else |
| -- RM 7.4 (6): If the subtype defined by the subtype_indication in |
| -- the deferred declaration is constrained, then the subtype defined |
| -- by the subtype_indication in the full declaration shall match it |
| -- statically. |
| |
| Check_Possible_Deferred_Completion |
| (Prev_Id => Prev, |
| Prev_Obj_Def => Object_Definition (Parent (Prev)), |
| Curr_Obj_Def => Obj_Def); |
| |
| Set_Full_View (Prev, Id); |
| Set_Is_Public (Id, Is_Public (Prev)); |
| Set_Is_Internal (Id); |
| Append_Entity (Id, Current_Scope); |
| |
| -- Check ALIASED present if present before (RM 7.4(7)) |
| |
| if Is_Aliased (Prev) |
| and then not Aliased_Present (N) |
| then |
| Error_Msg_Sloc := Sloc (Prev); |
| Error_Msg_N ("ALIASED required (see declaration#)", N); |
| end if; |
| |
| -- Check that placement is in private part and that the incomplete |
| -- declaration appeared in the visible part. |
| |
| if Ekind (Current_Scope) = E_Package |
| and then not In_Private_Part (Current_Scope) |
| then |
| Error_Msg_Sloc := Sloc (Prev); |
| Error_Msg_N ("full constant for declaration#" |
| & " must be in private part", N); |
| |
| elsif Ekind (Current_Scope) = E_Package |
| and then List_Containing (Parent (Prev)) |
| /= Visible_Declarations |
| (Specification (Unit_Declaration_Node (Current_Scope))) |
| then |
| Error_Msg_N |
| ("deferred constant must be declared in visible part", |
| Parent (Prev)); |
| end if; |
| |
| if Is_Access_Type (T) |
| and then Nkind (Expression (N)) = N_Allocator |
| then |
| Check_Recursive_Declaration (Designated_Type (T)); |
| end if; |
| end if; |
| end Constant_Redeclaration; |
| |
| ---------------------- |
| -- Constrain_Access -- |
| ---------------------- |
| |
| procedure Constrain_Access |
| (Def_Id : in out Entity_Id; |
| S : Node_Id; |
| Related_Nod : Node_Id) |
| is |
| T : constant Entity_Id := Entity (Subtype_Mark (S)); |
| Desig_Type : constant Entity_Id := Designated_Type (T); |
| Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod); |
| Constraint_OK : Boolean := True; |
| |
| function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean; |
| -- Simple predicate to test for defaulted discriminants |
| -- Shouldn't this be in sem_util??? |
| |
| --------------------------------- |
| -- Has_Defaulted_Discriminants -- |
| --------------------------------- |
| |
| function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is |
| begin |
| return Has_Discriminants (Typ) |
| and then Present (First_Discriminant (Typ)) |
| and then Present |
| (Discriminant_Default_Value (First_Discriminant (Typ))); |
| end Has_Defaulted_Discriminants; |
| |
| -- Start of processing for Constrain_Access |
| |
| begin |
| if Is_Array_Type (Desig_Type) then |
| Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P'); |
| |
| elsif (Is_Record_Type (Desig_Type) |
| or else Is_Incomplete_Or_Private_Type (Desig_Type)) |
| and then not Is_Constrained (Desig_Type) |
| then |
| -- ??? The following code is a temporary kludge to ignore a |
| -- discriminant constraint on access type if it is constraining |
| -- the current record. Avoid creating the implicit subtype of the |
| -- record we are currently compiling since right now, we cannot |
| -- handle these. For now, just return the access type itself. |
| |
| if Desig_Type = Current_Scope |
| and then No (Def_Id) |
| then |
| Set_Ekind (Desig_Subtype, E_Record_Subtype); |
| Def_Id := Entity (Subtype_Mark (S)); |
| |
| -- This call added to ensure that the constraint is analyzed |
| -- (needed for a B test). Note that we still return early from |
| -- this procedure to avoid recursive processing. ??? |
| |
| Constrain_Discriminated_Type |
| (Desig_Subtype, S, Related_Nod, For_Access => True); |
| return; |
| end if; |
| |
| if Ekind (T) = E_General_Access_Type |
| and then Has_Private_Declaration (Desig_Type) |
| and then In_Open_Scopes (Scope (Desig_Type)) |
| then |
| -- Enforce rule that the constraint is illegal if there is |
| -- an unconstrained view of the designated type. This means |
| -- that the partial view (either a private type declaration or |
| -- a derivation from a private type) has no discriminants. |
| -- (Defect Report 8652/0008, Technical Corrigendum 1, checked |
| -- by ACATS B371001). |
| -- Rule updated for Ada 2005: the private type is said to have |
| -- a constrained partial view, given that objects of the type |
| -- can be declared. |
| |
| declare |
| Pack : constant Node_Id := |
| Unit_Declaration_Node (Scope (Desig_Type)); |
| Decls : List_Id; |
| Decl : Node_Id; |
| |
| begin |
| if Nkind (Pack) = N_Package_Declaration then |
| Decls := Visible_Declarations (Specification (Pack)); |
| Decl := First (Decls); |
| while Present (Decl) loop |
| if (Nkind (Decl) = N_Private_Type_Declaration |
| and then |
| Chars (Defining_Identifier (Decl)) = |
| Chars (Desig_Type)) |
| |
| or else |
| (Nkind (Decl) = N_Full_Type_Declaration |
| and then |
| Chars (Defining_Identifier (Decl)) = |
| Chars (Desig_Type) |
| and then Is_Derived_Type (Desig_Type) |
| and then |
| Has_Private_Declaration (Etype (Desig_Type))) |
| then |
| if No (Discriminant_Specifications (Decl)) then |
| Error_Msg_N |
| ("cannot constrain general access type if " & |
| "designated type has constrained partial view", |
| S); |
| end if; |
| |
| exit; |
| end if; |
| |
| Next (Decl); |
| end loop; |
| end if; |
| end; |
| end if; |
| |
| Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod, |
| For_Access => True); |
| |
| elsif (Is_Task_Type (Desig_Type) |
| or else Is_Protected_Type (Desig_Type)) |
| and then not Is_Constrained (Desig_Type) |
| then |
| Constrain_Concurrent |
| (Desig_Subtype, S, Related_Nod, Desig_Type, ' '); |
| |
| else |
| Error_Msg_N ("invalid constraint on access type", S); |
| Desig_Subtype := Desig_Type; -- Ignore invalid constraint. |
| Constraint_OK := False; |
| end if; |
| |
| if No (Def_Id) then |
| Def_Id := Create_Itype (E_Access_Subtype, Related_Nod); |
| else |
| Set_Ekind (Def_Id, E_Access_Subtype); |
| end if; |
| |
| if Constraint_OK then |
| Set_Etype (Def_Id, Base_Type (T)); |
| |
| if Is_Private_Type (Desig_Type) then |
| Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod); |
| end if; |
| else |
| Set_Etype (Def_Id, Any_Type); |
| end if; |
| |
| Set_Size_Info (Def_Id, T); |
| Set_Is_Constrained (Def_Id, Constraint_OK); |
| Set_Directly_Designated_Type (Def_Id, Desig_Subtype); |
| Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id)); |
| Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T)); |
| |
| Conditional_Delay (Def_Id, T); |
| |
| -- AI-363 : Subtypes of general access types whose designated types have |
| -- default discriminants are disallowed. In instances, the rule has to |
| -- be checked against the actual, of which T is the subtype. In a |
| -- generic body, the rule is checked assuming that the actual type has |
| -- defaulted discriminants. |
| |
| if Ada_Version >= Ada_05 then |
| if Ekind (Base_Type (T)) = E_General_Access_Type |
| and then Has_Defaulted_Discriminants (Desig_Type) |
| then |
| Error_Msg_N |
| ("access subype of general access type not allowed", S); |
| Error_Msg_N ("\ when discriminants have defaults", S); |
| |
| elsif Is_Access_Type (T) |
| and then Is_Generic_Type (Desig_Type) |
| and then Has_Discriminants (Desig_Type) |
| and then In_Package_Body (Current_Scope) |
| then |
| Error_Msg_N ("access subtype not allowed in generic body", S); |
| Error_Msg_N |
| ("\ wben designated type is a discriminated formal", S); |
| end if; |
| end if; |
| end Constrain_Access; |
| |
| --------------------- |
| -- Constrain_Array -- |
| --------------------- |
| |
| procedure Constrain_Array |
| (Def_Id : in out Entity_Id; |
| SI : Node_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id; |
| Suffix : Character) |
| is |
| C : constant Node_Id := Constraint (SI); |
| Number_Of_Constraints : Nat := 0; |
| Index : Node_Id; |
| S, T : Entity_Id; |
| Constraint_OK : Boolean := True; |
| |
| begin |
| T := Entity (Subtype_Mark (SI)); |
| |
| if Ekind (T) in Access_Kind then |
| T := Designated_Type (T); |
| end if; |
| |
| -- If an index constraint follows a subtype mark in a subtype indication |
| -- then the type or subtype denoted by the subtype mark must not already |
| -- impose an index constraint. The subtype mark must denote either an |
| -- unconstrained array type or an access type whose designated type |
| -- is such an array type... (RM 3.6.1) |
| |
| if Is_Constrained (T) then |
| Error_Msg_N |
| ("array type is already constrained", Subtype_Mark (SI)); |
| Constraint_OK := False; |
| |
| else |
| S := First (Constraints (C)); |
| while Present (S) loop |
| Number_Of_Constraints := Number_Of_Constraints + 1; |
| Next (S); |
| end loop; |
| |
| -- In either case, the index constraint must provide a discrete |
| -- range for each index of the array type and the type of each |
| -- discrete range must be the same as that of the corresponding |
| -- index. (RM 3.6.1) |
| |
| if Number_Of_Constraints /= Number_Dimensions (T) then |
| Error_Msg_NE ("incorrect number of index constraints for }", C, T); |
| Constraint_OK := False; |
| |
| else |
| S := First (Constraints (C)); |
| Index := First_Index (T); |
| Analyze (Index); |
| |
| -- Apply constraints to each index type |
| |
| for J in 1 .. Number_Of_Constraints loop |
| Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J); |
| Next (Index); |
| Next (S); |
| end loop; |
| |
| end if; |
| end if; |
| |
| if No (Def_Id) then |
| Def_Id := |
| Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix); |
| Set_Parent (Def_Id, Related_Nod); |
| |
| else |
| Set_Ekind (Def_Id, E_Array_Subtype); |
| end if; |
| |
| Set_Size_Info (Def_Id, (T)); |
| Set_First_Rep_Item (Def_Id, First_Rep_Item (T)); |
| Set_Etype (Def_Id, Base_Type (T)); |
| |
| if Constraint_OK then |
| Set_First_Index (Def_Id, First (Constraints (C))); |
| else |
| Set_First_Index (Def_Id, First_Index (T)); |
| end if; |
| |
| Set_Is_Constrained (Def_Id, True); |
| Set_Is_Aliased (Def_Id, Is_Aliased (T)); |
| Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id)); |
| |
| Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T)); |
| Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T)); |
| |
| -- Build a freeze node if parent still needs one. Also, make sure |
| -- that the Depends_On_Private status is set (explanation ???) |
| -- and also that a conditional delay is set. |
| |
| Set_Depends_On_Private (Def_Id, Depends_On_Private (T)); |
| Conditional_Delay (Def_Id, T); |
| |
| end Constrain_Array; |
| |
| ------------------------------ |
| -- Constrain_Component_Type -- |
| ------------------------------ |
| |
| function Constrain_Component_Type |
| (Comp : Entity_Id; |
| Constrained_Typ : Entity_Id; |
| Related_Node : Node_Id; |
| Typ : Entity_Id; |
| Constraints : Elist_Id) return Entity_Id |
| is |
| Loc : constant Source_Ptr := Sloc (Constrained_Typ); |
| Compon_Type : constant Entity_Id := Etype (Comp); |
| |
| function Build_Constrained_Array_Type |
| (Old_Type : Entity_Id) return Entity_Id; |
| -- If Old_Type is an array type, one of whose indices is constrained |
| -- by a discriminant, build an Itype whose constraint replaces the |
| -- discriminant with its value in the constraint. |
| |
| function Build_Constrained_Discriminated_Type |
| (Old_Type : Entity_Id) return Entity_Id; |
| -- Ditto for record components |
| |
| function Build_Constrained_Access_Type |
| (Old_Type : Entity_Id) return Entity_Id; |
| -- Ditto for access types. Makes use of previous two functions, to |
| -- constrain designated type. |
| |
| function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id; |
| -- T is an array or discriminated type, C is a list of constraints |
| -- that apply to T. This routine builds the constrained subtype. |
| |
| function Is_Discriminant (Expr : Node_Id) return Boolean; |
| -- Returns True if Expr is a discriminant |
| |
| function Get_Discr_Value (Discrim : Entity_Id) return Node_Id; |
| -- Find the value of discriminant Discrim in Constraint |
| |
| ----------------------------------- |
| -- Build_Constrained_Access_Type -- |
| ----------------------------------- |
| |
| function Build_Constrained_Access_Type |
| (Old_Type : Entity_Id) return Entity_Id |
| is |
| Desig_Type : constant Entity_Id := Designated_Type (Old_Type); |
| Itype : Entity_Id; |
| Desig_Subtype : Entity_Id; |
| Scop : Entity_Id; |
| |
| begin |
| -- if the original access type was not embedded in the enclosing |
| -- type definition, there is no need to produce a new access |
| -- subtype. In fact every access type with an explicit constraint |
| -- generates an itype whose scope is the enclosing record. |
| |
| if not Is_Type (Scope (Old_Type)) then |
| return Old_Type; |
| |
| elsif Is_Array_Type (Desig_Type) then |
| Desig_Subtype := Build_Constrained_Array_Type (Desig_Type); |
| |
| elsif Has_Discriminants (Desig_Type) then |
| |
| -- This may be an access type to an enclosing record type for |
| -- which we are constructing the constrained components. Return |
| -- the enclosing record subtype. This is not always correct, |
| -- but avoids infinite recursion. ??? |
| |
| Desig_Subtype := Any_Type; |
| |
| for J in reverse 0 .. Scope_Stack.Last loop |
| Scop := Scope_Stack.Table (J).Entity; |
| |
| if Is_Type (Scop) |
| and then Base_Type (Scop) = Base_Type (Desig_Type) |
| then |
| Desig_Subtype := Scop; |
| end if; |
| |
| exit when not Is_Type (Scop); |
| end loop; |
| |
| if Desig_Subtype = Any_Type then |
| Desig_Subtype := |
| Build_Constrained_Discriminated_Type (Desig_Type); |
| end if; |
| |
| else |
| return Old_Type; |
| end if; |
| |
| if Desig_Subtype /= Desig_Type then |
| |
| -- The Related_Node better be here or else we won't be able |
| -- to attach new itypes to a node in the tree. |
| |
| pragma Assert (Present (Related_Node)); |
| |
| Itype := Create_Itype (E_Access_Subtype, Related_Node); |
| |
| Set_Etype (Itype, Base_Type (Old_Type)); |
| Set_Size_Info (Itype, (Old_Type)); |
| Set_Directly_Designated_Type (Itype, Desig_Subtype); |
| Set_Depends_On_Private (Itype, Has_Private_Component |
| (Old_Type)); |
| Set_Is_Access_Constant (Itype, Is_Access_Constant |
| (Old_Type)); |
| |
| -- The new itype needs freezing when it depends on a not frozen |
| -- type and the enclosing subtype needs freezing. |
| |
| if Has_Delayed_Freeze (Constrained_Typ) |
| and then not Is_Frozen (Constrained_Typ) |
| then |
| Conditional_Delay (Itype, Base_Type (Old_Type)); |
| end if; |
| |
| return Itype; |
| |
| else |
| return Old_Type; |
| end if; |
| end Build_Constrained_Access_Type; |
| |
| ---------------------------------- |
| -- Build_Constrained_Array_Type -- |
| ---------------------------------- |
| |
| function Build_Constrained_Array_Type |
| (Old_Type : Entity_Id) return Entity_Id |
| is |
| Lo_Expr : Node_Id; |
| Hi_Expr : Node_Id; |
| Old_Index : Node_Id; |
| Range_Node : Node_Id; |
| Constr_List : List_Id; |
| |
| Need_To_Create_Itype : Boolean := False; |
| |
| begin |
| Old_Index := First_Index (Old_Type); |
| while Present (Old_Index) loop |
| Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr); |
| |
| if Is_Discriminant (Lo_Expr) |
| or else Is_Discriminant (Hi_Expr) |
| then |
| Need_To_Create_Itype := True; |
| end if; |
| |
| Next_Index (Old_Index); |
| end loop; |
| |
| if Need_To_Create_Itype then |
| Constr_List := New_List; |
| |
| Old_Index := First_Index (Old_Type); |
| while Present (Old_Index) loop |
| Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr); |
| |
| if Is_Discriminant (Lo_Expr) then |
| Lo_Expr := Get_Discr_Value (Lo_Expr); |
| end if; |
| |
| if Is_Discriminant (Hi_Expr) then |
| Hi_Expr := Get_Discr_Value (Hi_Expr); |
| end if; |
| |
| Range_Node := |
| Make_Range |
| (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr)); |
| |
| Append (Range_Node, To => Constr_List); |
| |
| Next_Index (Old_Index); |
| end loop; |
| |
| return Build_Subtype (Old_Type, Constr_List); |
| |
| else |
| return Old_Type; |
| end if; |
| end Build_Constrained_Array_Type; |
| |
| ------------------------------------------ |
| -- Build_Constrained_Discriminated_Type -- |
| ------------------------------------------ |
| |
| function Build_Constrained_Discriminated_Type |
| (Old_Type : Entity_Id) return Entity_Id |
| is |
| Expr : Node_Id; |
| Constr_List : List_Id; |
| Old_Constraint : Elmt_Id; |
| |
| Need_To_Create_Itype : Boolean := False; |
| |
| begin |
| Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type)); |
| while Present (Old_Constraint) loop |
| Expr := Node (Old_Constraint); |
| |
| if Is_Discriminant (Expr) then |
| Need_To_Create_Itype := True; |
| end if; |
| |
| Next_Elmt (Old_Constraint); |
| end loop; |
| |
| if Need_To_Create_Itype then |
| Constr_List := New_List; |
| |
| Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type)); |
| while Present (Old_Constraint) loop |
| Expr := Node (Old_Constraint); |
| |
| if Is_Discriminant (Expr) then |
| Expr := Get_Discr_Value (Expr); |
| end if; |
| |
| Append (New_Copy_Tree (Expr), To => Constr_List); |
| |
| Next_Elmt (Old_Constraint); |
| end loop; |
| |
| return Build_Subtype (Old_Type, Constr_List); |
| |
| else |
| return Old_Type; |
| end if; |
| end Build_Constrained_Discriminated_Type; |
| |
| ------------------- |
| -- Build_Subtype -- |
| ------------------- |
| |
| function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is |
| Indic : Node_Id; |
| Subtyp_Decl : Node_Id; |
| Def_Id : Entity_Id; |
| Btyp : Entity_Id := Base_Type (T); |
| |
| begin |
| -- The Related_Node better be here or else we won't be able to |
| -- attach new itypes to a node in the tree. |
| |
| pragma Assert (Present (Related_Node)); |
| |
| -- If the view of the component's type is incomplete or private |
| -- with unknown discriminants, then the constraint must be applied |
| -- to the full type. |
| |
| if Has_Unknown_Discriminants (Btyp) |
| and then Present (Underlying_Type (Btyp)) |
| then |
| Btyp := Underlying_Type (Btyp); |
| end if; |
| |
| Indic := |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Occurrence_Of (Btyp, Loc), |
| Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C)); |
| |
| Def_Id := Create_Itype (Ekind (T), Related_Node); |
| |
| Subtyp_Decl := |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Def_Id, |
| Subtype_Indication => Indic); |
| |
| Set_Parent (Subtyp_Decl, Parent (Related_Node)); |
| |
| -- Itypes must be analyzed with checks off (see package Itypes) |
| |
| Analyze (Subtyp_Decl, Suppress => All_Checks); |
| |
| return Def_Id; |
| end Build_Subtype; |
| |
| --------------------- |
| -- Get_Discr_Value -- |
| --------------------- |
| |
| function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is |
| D : Entity_Id; |
| E : Elmt_Id; |
| G : Elmt_Id; |
| |
| begin |
| -- The discriminant may be declared for the type, in which case we |
| -- find it by iterating over the list of discriminants. If the |
| -- discriminant is inherited from a parent type, it appears as the |
| -- corresponding discriminant of the current type. This will be the |
| -- case when constraining an inherited component whose constraint is |
| -- given by a discriminant of the parent. |
| |
| D := First_Discriminant (Typ); |
| E := First_Elmt (Constraints); |
| while Present (D) loop |
| if D = Entity (Discrim) |
| or else Corresponding_Discriminant (D) = Entity (Discrim) |
| then |
| return Node (E); |
| end if; |
| |
| Next_Discriminant (D); |
| Next_Elmt (E); |
| end loop; |
| |
| -- The corresponding_Discriminant mechanism is incomplete, because |
| -- the correspondence between new and old discriminants is not one |
| -- to one: one new discriminant can constrain several old ones. In |
| -- that case, scan sequentially the stored_constraint, the list of |
| -- discriminants of the parents, and the constraints. |
| |
| if Is_Derived_Type (Typ) |
| and then Present (Stored_Constraint (Typ)) |
| and then Scope (Entity (Discrim)) = Etype (Typ) |
| then |
| D := First_Discriminant (Etype (Typ)); |
| E := First_Elmt (Constraints); |
| G := First_Elmt (Stored_Constraint (Typ)); |
| while Present (D) loop |
| if D = Entity (Discrim) then |
| return Node (E); |
| end if; |
| |
| Next_Discriminant (D); |
| Next_Elmt (E); |
| Next_Elmt (G); |
| end loop; |
| end if; |
| |
| -- Something is wrong if we did not find the value |
| |
| raise Program_Error; |
| end Get_Discr_Value; |
| |
| --------------------- |
| -- Is_Discriminant -- |
| --------------------- |
| |
| function Is_Discriminant (Expr : Node_Id) return Boolean is |
| Discrim_Scope : Entity_Id; |
| |
| begin |
| if Denotes_Discriminant (Expr) then |
| Discrim_Scope := Scope (Entity (Expr)); |
| |
| -- Either we have a reference to one of Typ's discriminants, |
| |
| pragma Assert (Discrim_Scope = Typ |
| |
| -- or to the discriminants of the parent type, in the case |
| -- of a derivation of a tagged type with variants. |
| |
| or else Discrim_Scope = Etype (Typ) |
| or else Full_View (Discrim_Scope) = Etype (Typ) |
| |
| -- or same as above for the case where the discriminants |
| -- were declared in Typ's private view. |
| |
| or else (Is_Private_Type (Discrim_Scope) |
| and then Chars (Discrim_Scope) = Chars (Typ)) |
| |
| -- or else we are deriving from the full view and the |
| -- discriminant is declared in the private entity. |
| |
| or else (Is_Private_Type (Typ) |
| and then Chars (Discrim_Scope) = Chars (Typ)) |
| |
| -- or we have a class-wide type, in which case make sure the |
| -- discriminant found belongs to the root type. |
| |
| or else (Is_Class_Wide_Type (Typ) |
| and then Etype (Typ) = Discrim_Scope)); |
| |
| return True; |
| end if; |
| |
| -- In all other cases we have something wrong |
| |
| return False; |
| end Is_Discriminant; |
| |
| -- Start of processing for Constrain_Component_Type |
| |
| begin |
| if Nkind (Parent (Comp)) = N_Component_Declaration |
| and then Comes_From_Source (Parent (Comp)) |
| and then Comes_From_Source |
| (Subtype_Indication (Component_Definition (Parent (Comp)))) |
| and then |
| Is_Entity_Name |
| (Subtype_Indication (Component_Definition (Parent (Comp)))) |
| then |
| return Compon_Type; |
| |
| elsif Is_Array_Type (Compon_Type) then |
| return Build_Constrained_Array_Type (Compon_Type); |
| |
| elsif Has_Discriminants (Compon_Type) then |
| return Build_Constrained_Discriminated_Type (Compon_Type); |
| |
| elsif Is_Access_Type (Compon_Type) then |
| return Build_Constrained_Access_Type (Compon_Type); |
| |
| else |
| return Compon_Type; |
| end if; |
| end Constrain_Component_Type; |
| |
| -------------------------- |
| -- Constrain_Concurrent -- |
| -------------------------- |
| |
| -- For concurrent types, the associated record value type carries the same |
| -- discriminants, so when we constrain a concurrent type, we must constrain |
| -- the corresponding record type as well. |
| |
| procedure Constrain_Concurrent |
| (Def_Id : in out Entity_Id; |
| SI : Node_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id; |
| Suffix : Character) |
| is |
| T_Ent : Entity_Id := Entity (Subtype_Mark (SI)); |
| T_Val : Entity_Id; |
| |
| begin |
| if Ekind (T_Ent) in Access_Kind then |
| T_Ent := Designated_Type (T_Ent); |
| end if; |
| |
| T_Val := Corresponding_Record_Type (T_Ent); |
| |
| if Present (T_Val) then |
| |
| if No (Def_Id) then |
| Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix); |
| end if; |
| |
| Constrain_Discriminated_Type (Def_Id, SI, Related_Nod); |
| |
| Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id)); |
| Set_Corresponding_Record_Type (Def_Id, |
| Constrain_Corresponding_Record |
| (Def_Id, T_Val, Related_Nod, Related_Id)); |
| |
| else |
| -- If there is no associated record, expansion is disabled and this |
| -- is a generic context. Create a subtype in any case, so that |
| -- semantic analysis can proceed. |
| |
| if No (Def_Id) then |
| Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix); |
| end if; |
| |
| Constrain_Discriminated_Type (Def_Id, SI, Related_Nod); |
| end if; |
| end Constrain_Concurrent; |
| |
| ------------------------------------ |
| -- Constrain_Corresponding_Record -- |
| ------------------------------------ |
| |
| function Constrain_Corresponding_Record |
| (Prot_Subt : Entity_Id; |
| Corr_Rec : Entity_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id) return Entity_Id |
| is |
| T_Sub : constant Entity_Id := |
| Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V'); |
| |
| begin |
| Set_Etype (T_Sub, Corr_Rec); |
| Init_Size_Align (T_Sub); |
| Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt)); |
| Set_Is_Constrained (T_Sub, True); |
| Set_First_Entity (T_Sub, First_Entity (Corr_Rec)); |
| Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec)); |
| |
| Conditional_Delay (T_Sub, Corr_Rec); |
| |
| if Has_Discriminants (Prot_Subt) then -- False only if errors. |
| Set_Discriminant_Constraint |
| (T_Sub, Discriminant_Constraint (Prot_Subt)); |
| Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub); |
| Create_Constrained_Components |
| (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub)); |
| end if; |
| |
| Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub)); |
| |
| return T_Sub; |
| end Constrain_Corresponding_Record; |
| |
| ----------------------- |
| -- Constrain_Decimal -- |
| ----------------------- |
| |
| procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is |
| T : constant Entity_Id := Entity (Subtype_Mark (S)); |
| C : constant Node_Id := Constraint (S); |
| Loc : constant Source_Ptr := Sloc (C); |
| Range_Expr : Node_Id; |
| Digits_Expr : Node_Id; |
| Digits_Val : Uint; |
| Bound_Val : Ureal; |
| |
| begin |
| Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype); |
| |
| if Nkind (C) = N_Range_Constraint then |
| Range_Expr := Range_Expression (C); |
| Digits_Val := Digits_Value (T); |
| |
| else |
| pragma Assert (Nkind (C) = N_Digits_Constraint); |
| Digits_Expr := Digits_Expression (C); |
| Analyze_And_Resolve (Digits_Expr, Any_Integer); |
| |
| Check_Digits_Expression (Digits_Expr); |
| Digits_Val := Expr_Value (Digits_Expr); |
| |
| if Digits_Val > Digits_Value (T) then |
| Error_Msg_N |
| ("digits expression is incompatible with subtype", C); |
| Digits_Val := Digits_Value (T); |
| end if; |
| |
| if Present (Range_Constraint (C)) then |
| Range_Expr := Range_Expression (Range_Constraint (C)); |
| else |
| Range_Expr := Empty; |
| end if; |
| end if; |
| |
| Set_Etype (Def_Id, Base_Type (T)); |
| Set_Size_Info (Def_Id, (T)); |
| Set_First_Rep_Item (Def_Id, First_Rep_Item (T)); |
| Set_Delta_Value (Def_Id, Delta_Value (T)); |
| Set_Scale_Value (Def_Id, Scale_Value (T)); |
| Set_Small_Value (Def_Id, Small_Value (T)); |
| Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T)); |
| Set_Digits_Value (Def_Id, Digits_Val); |
| |
| -- Manufacture range from given digits value if no range present |
| |
| if No (Range_Expr) then |
| Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T); |
| Range_Expr := |
| Make_Range (Loc, |
| Low_Bound => |
| Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))), |
| High_Bound => |
| Convert_To (T, Make_Real_Literal (Loc, Bound_Val))); |
| end if; |
| |
| Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T); |
| Set_Discrete_RM_Size (Def_Id); |
| |
| -- Unconditionally delay the freeze, since we cannot set size |
| -- information in all cases correctly until the freeze point. |
| |
| Set_Has_Delayed_Freeze (Def_Id); |
| end Constrain_Decimal; |
| |
| ---------------------------------- |
| -- Constrain_Discriminated_Type -- |
| ---------------------------------- |
| |
| procedure Constrain_Discriminated_Type |
| (Def_Id : Entity_Id; |
| S : Node_Id; |
| Related_Nod : Node_Id; |
| For_Access : Boolean := False) |
| is |
| E : constant Entity_Id := Entity (Subtype_Mark (S)); |
| T : Entity_Id; |
| C : Node_Id; |
| Elist : Elist_Id := New_Elmt_List; |
| |
| procedure Fixup_Bad_Constraint; |
| -- This is called after finding a bad constraint, and after having |
| -- posted an appropriate error message. The mission is to leave the |
| -- entity T in as reasonable state as possible! |
| |
| -------------------------- |
| -- Fixup_Bad_Constraint -- |
| -------------------------- |
| |
| procedure Fixup_Bad_Constraint is |
| begin |
| -- Set a reasonable Ekind for the entity. For an incomplete type, |
| -- we can't do much, but for other types, we can set the proper |
| -- corresponding subtype kind. |
| |
| if Ekind (T) = E_Incomplete_Type then |
| Set_Ekind (Def_Id, Ekind (T)); |
| else |
| Set_Ekind (Def_Id, Subtype_Kind (Ekind (T))); |
| end if; |
| |
| Set_Etype (Def_Id, Any_Type); |
| Set_Error_Posted (Def_Id); |
| end Fixup_Bad_Constraint; |
| |
| -- Start of processing for Constrain_Discriminated_Type |
| |
| begin |
| C := Constraint (S); |
| |
| -- A discriminant constraint is only allowed in a subtype indication, |
| -- after a subtype mark. This subtype mark must denote either a type |
| -- with discriminants, or an access type whose designated type is a |
| -- type with discriminants. A discriminant constraint specifies the |
| -- values of these discriminants (RM 3.7.2(5)). |
| |
| T := Base_Type (Entity (Subtype_Mark (S))); |
| |
| if Ekind (T) in Access_Kind then |
| T := Designated_Type (T); |
| end if; |
| |
| -- Check that the type has visible discriminants. The type may be |
| -- a private type with unknown discriminants whose full view has |
| -- discriminants which are invisible. |
| |
| if not Has_Discriminants (T) |
| or else |
| (Has_Unknown_Discriminants (T) |
| and then Is_Private_Type (T)) |
| then |
| Error_Msg_N ("invalid constraint: type has no discriminant", C); |
| Fixup_Bad_Constraint; |
| return; |
| |
| elsif Is_Constrained (E) |
| or else (Ekind (E) = E_Class_Wide_Subtype |
| and then Present (Discriminant_Constraint (E))) |
| then |
| Error_Msg_N ("type is already constrained", Subtype_Mark (S)); |
| Fixup_Bad_Constraint; |
| return; |
| end if; |
| |
| -- T may be an unconstrained subtype (e.g. a generic actual). |
| -- Constraint applies to the base type. |
| |
| T := Base_Type (T); |
| |
| Elist := Build_Discriminant_Constraints (T, S); |
| |
| -- If the list returned was empty we had an error in building the |
| -- discriminant constraint. We have also already signalled an error |
| -- in the incomplete type case |
| |
| if Is_Empty_Elmt_List (Elist) then |
| Fixup_Bad_Constraint; |
| return; |
| end if; |
| |
| Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access); |
| end Constrain_Discriminated_Type; |
| |
| --------------------------- |
| -- Constrain_Enumeration -- |
| --------------------------- |
| |
| procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is |
| T : constant Entity_Id := Entity (Subtype_Mark (S)); |
| C : constant Node_Id := Constraint (S); |
| |
| begin |
| Set_Ekind (Def_Id, E_Enumeration_Subtype); |
| |
| Set_First_Literal (Def_Id, First_Literal (Base_Type (T))); |
| |
| Set_Etype (Def_Id, Base_Type (T)); |
| Set_Size_Info (Def_Id, (T)); |
| Set_First_Rep_Item (Def_Id, First_Rep_Item (T)); |
| Set_Is_Character_Type (Def_Id, Is_Character_Type (T)); |
| |
| Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T); |
| |
| Set_Discrete_RM_Size (Def_Id); |
| end Constrain_Enumeration; |
| |
| ---------------------- |
| -- Constrain_Float -- |
| ---------------------- |
| |
| procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is |
| T : constant Entity_Id := Entity (Subtype_Mark (S)); |
| C : Node_Id; |
| D : Node_Id; |
| Rais : Node_Id; |
| |
| begin |
| Set_Ekind (Def_Id, E_Floating_Point_Subtype); |
| |
| Set_Etype (Def_Id, Base_Type (T)); |
| Set_Size_Info (Def_Id, (T)); |
| Set_First_Rep_Item (Def_Id, First_Rep_Item (T)); |
| |
| -- Process the constraint |
| |
| C := Constraint (S); |
| |
| -- Digits constraint present |
| |
| if Nkind (C) = N_Digits_Constraint then |
| Check_Restriction (No_Obsolescent_Features, C); |
| |
| if Warn_On_Obsolescent_Feature then |
| Error_Msg_N |
| ("subtype digits constraint is an " & |
| "obsolescent feature ('R'M 'J.3(8))?", C); |
| end if; |
| |
| D := Digits_Expression (C); |
| Analyze_And_Resolve (D, Any_Integer); |
| Check_Digits_Expression (D); |
| Set_Digits_Value (Def_Id, Expr_Value (D)); |
| |
| -- Check that digits value is in range. Obviously we can do this |
| -- at compile time, but it is strictly a runtime check, and of |
| -- course there is an ACVC test that checks this! |
| |
| if Digits_Value (Def_Id) > Digits_Value (T) then |
| Error_Msg_Uint_1 := Digits_Value (T); |
| Error_Msg_N ("?digits value is too large, maximum is ^", D); |
| Rais := |
| Make_Raise_Constraint_Error (Sloc (D), |
| Reason => CE_Range_Check_Failed); |
| Insert_Action (Declaration_Node (Def_Id), Rais); |
| end if; |
| |
| C := Range_Constraint (C); |
| |
| -- No digits constraint present |
| |
| else |
| Set_Digits_Value (Def_Id, Digits_Value (T)); |
| end if; |
| |
| -- Range constraint present |
| |
| if Nkind (C) = N_Range_Constraint then |
| Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T); |
| |
| -- No range constraint present |
| |
| else |
| pragma Assert (No (C)); |
| Set_Scalar_Range (Def_Id, Scalar_Range (T)); |
| end if; |
| |
| Set_Is_Constrained (Def_Id); |
| end Constrain_Float; |
| |
| --------------------- |
| -- Constrain_Index -- |
| --------------------- |
| |
| procedure Constrain_Index |
| (Index : Node_Id; |
| S : Node_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id; |
| Suffix : Character; |
| Suffix_Index : Nat) |
| is |
| Def_Id : Entity_Id; |
| R : Node_Id := Empty; |
| T : constant Entity_Id := Etype (Index); |
| |
| begin |
| if Nkind (S) = N_Range |
| or else |
| (Nkind (S) = N_Attribute_Reference |
| and then Attribute_Name (S) = Name_Range) |
| then |
| -- A Range attribute will transformed into N_Range by Resolve |
| |
| Analyze (S); |
| Set_Etype (S, T); |
| R := S; |
| |
| Process_Range_Expr_In_Decl (R, T, Empty_List); |
| |
| if not Error_Posted (S) |
| and then |
| (Nkind (S) /= N_Range |
| or else not Covers (T, (Etype (Low_Bound (S)))) |
| or else not Covers (T, (Etype (High_Bound (S))))) |
| then |
| if Base_Type (T) /= Any_Type |
| and then Etype (Low_Bound (S)) /= Any_Type |
| and then Etype (High_Bound (S)) /= Any_Type |
| then |
| Error_Msg_N ("range expected", S); |
| end if; |
| end if; |
| |
| elsif Nkind (S) = N_Subtype_Indication then |
| |
| -- The parser has verified that this is a discrete indication |
| |
| Resolve_Discrete_Subtype_Indication (S, T); |
| R := Range_Expression (Constraint (S)); |
| |
| elsif Nkind (S) = N_Discriminant_Association then |
| |
| -- Syntactically valid in subtype indication |
| |
| Error_Msg_N ("invalid index constraint", S); |
| Rewrite (S, New_Occurrence_Of (T, Sloc (S))); |
| return; |
| |
| -- Subtype_Mark case, no anonymous subtypes to construct |
| |
| else |
| Analyze (S); |
| |
| if Is_Entity_Name (S) then |
| if not Is_Type (Entity (S)) then |
| Error_Msg_N ("expect subtype mark for index constraint", S); |
| |
| elsif Base_Type (Entity (S)) /= Base_Type (T) then |
| Wrong_Type (S, Base_Type (T)); |
| end if; |
| |
| return; |
| |
| else |
| Error_Msg_N ("invalid index constraint", S); |
| Rewrite (S, New_Occurrence_Of (T, Sloc (S))); |
| return; |
| end if; |
| end if; |
| |
| Def_Id := |
| Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index); |
| |
| Set_Etype (Def_Id, Base_Type (T)); |
| |
| if Is_Modular_Integer_Type (T) then |
| Set_Ekind (Def_Id, E_Modular_Integer_Subtype); |
| |
| elsif Is_Integer_Type (T) then |
| Set_Ekind (Def_Id, E_Signed_Integer_Subtype); |
| |
| else |
| Set_Ekind (Def_Id, E_Enumeration_Subtype); |
| Set_Is_Character_Type (Def_Id, Is_Character_Type (T)); |
| end if; |
| |
| Set_Size_Info (Def_Id, (T)); |
| Set_RM_Size (Def_Id, RM_Size (T)); |
| Set_First_Rep_Item (Def_Id, First_Rep_Item (T)); |
| |
| Set_Scalar_Range (Def_Id, R); |
| |
| Set_Etype (S, Def_Id); |
| Set_Discrete_RM_Size (Def_Id); |
| end Constrain_Index; |
| |
| ----------------------- |
| -- Constrain_Integer -- |
| ----------------------- |
| |
| procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is |
| T : constant Entity_Id := Entity (Subtype_Mark (S)); |
| C : constant Node_Id := Constraint (S); |
| |
| begin |
| Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T); |
| |
| if Is_Modular_Integer_Type (T) then |
| Set_Ekind (Def_Id, E_Modular_Integer_Subtype); |
| else |
| Set_Ekind (Def_Id, E_Signed_Integer_Subtype); |
| end if; |
| |
| Set_Etype (Def_Id, Base_Type (T)); |
| Set_Size_Info (Def_Id, (T)); |
| Set_First_Rep_Item (Def_Id, First_Rep_Item (T)); |
| Set_Discrete_RM_Size (Def_Id); |
| end Constrain_Integer; |
| |
| ------------------------------ |
| -- Constrain_Ordinary_Fixed -- |
| ------------------------------ |
| |
| procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is |
| T : constant Entity_Id := Entity (Subtype_Mark (S)); |
| C : Node_Id; |
| D : Node_Id; |
| Rais : Node_Id; |
| |
| begin |
| Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype); |
| Set_Etype (Def_Id, Base_Type (T)); |
| Set_Size_Info (Def_Id, (T)); |
| Set_First_Rep_Item (Def_Id, First_Rep_Item (T)); |
| Set_Small_Value (Def_Id, Small_Value (T)); |
| |
| -- Process the constraint |
| |
| C := Constraint (S); |
| |
| -- Delta constraint present |
| |
| if Nkind (C) = N_Delta_Constraint then |
| Check_Restriction (No_Obsolescent_Features, C); |
| |
| if Warn_On_Obsolescent_Feature then |
| Error_Msg_S |
| ("subtype delta constraint is an " & |
| "obsolescent feature ('R'M 'J.3(7))?"); |
| end if; |
| |
| D := Delta_Expression (C); |
| Analyze_And_Resolve (D, Any_Real); |
| Check_Delta_Expression (D); |
| Set_Delta_Value (Def_Id, Expr_Value_R (D)); |
| |
| -- Check that delta value is in range. Obviously we can do this |
| -- at compile time, but it is strictly a runtime check, and of |
| -- course there is an ACVC test that checks this! |
| |
| if Delta_Value (Def_Id) < Delta_Value (T) then |
| Error_Msg_N ("?delta value is too small", D); |
| Rais := |
| Make_Raise_Constraint_Error (Sloc (D), |
| Reason => CE_Range_Check_Failed); |
| Insert_Action (Declaration_Node (Def_Id), Rais); |
| end if; |
| |
| C := Range_Constraint (C); |
| |
| -- No delta constraint present |
| |
| else |
| Set_Delta_Value (Def_Id, Delta_Value (T)); |
| end if; |
| |
| -- Range constraint present |
| |
| if Nkind (C) = N_Range_Constraint then |
| Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T); |
| |
| -- No range constraint present |
| |
| else |
| pragma Assert (No (C)); |
| Set_Scalar_Range (Def_Id, Scalar_Range (T)); |
| |
| end if; |
| |
| Set_Discrete_RM_Size (Def_Id); |
| |
| -- Unconditionally delay the freeze, since we cannot set size |
| -- information in all cases correctly until the freeze point. |
| |
| Set_Has_Delayed_Freeze (Def_Id); |
| end Constrain_Ordinary_Fixed; |
| |
| --------------------------- |
| -- Convert_Scalar_Bounds -- |
| --------------------------- |
| |
| procedure Convert_Scalar_Bounds |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id; |
| Loc : Source_Ptr) |
| is |
| Implicit_Base : constant Entity_Id := Base_Type (Derived_Type); |
| |
| Lo : Node_Id; |
| Hi : Node_Id; |
| Rng : Node_Id; |
| |
| begin |
| Lo := Build_Scalar_Bound |
| (Type_Low_Bound (Derived_Type), |
| Parent_Type, Implicit_Base); |
| |
| Hi := Build_Scalar_Bound |
| (Type_High_Bound (Derived_Type), |
| Parent_Type, Implicit_Base); |
| |
| Rng := |
| Make_Range (Loc, |
| Low_Bound => Lo, |
| High_Bound => Hi); |
| |
| Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type)); |
| |
| Set_Parent (Rng, N); |
| Set_Scalar_Range (Derived_Type, Rng); |
| |
| -- Analyze the bounds |
| |
| Analyze_And_Resolve (Lo, Implicit_Base); |
| Analyze_And_Resolve (Hi, Implicit_Base); |
| |
| -- Analyze the range itself, except that we do not analyze it if |
| -- the bounds are real literals, and we have a fixed-point type. |
| -- The reason for this is that we delay setting the bounds in this |
| -- case till we know the final Small and Size values (see circuit |
| -- in Freeze.Freeze_Fixed_Point_Type for further details). |
| |
| if Is_Fixed_Point_Type (Parent_Type) |
| and then Nkind (Lo) = N_Real_Literal |
| and then Nkind (Hi) = N_Real_Literal |
| then |
| return; |
| |
| -- Here we do the analysis of the range |
| |
| -- Note: we do this manually, since if we do a normal Analyze and |
| -- Resolve call, there are problems with the conversions used for |
| -- the derived type range. |
| |
| else |
| Set_Etype (Rng, Implicit_Base); |
| Set_Analyzed (Rng, True); |
| end if; |
| end Convert_Scalar_Bounds; |
| |
| ------------------- |
| -- Copy_And_Swap -- |
| ------------------- |
| |
| procedure Copy_And_Swap (Priv, Full : Entity_Id) is |
| begin |
| -- Initialize new full declaration entity by copying the pertinent |
| -- fields of the corresponding private declaration entity. |
| |
| -- We temporarily set Ekind to a value appropriate for a type to |
| -- avoid assert failures in Einfo from checking for setting type |
| -- attributes on something that is not a type. Ekind (Priv) is an |
| -- appropriate choice, since it allowed the attributes to be set |
| -- in the first place. This Ekind value will be modified later. |
| |
| Set_Ekind (Full, Ekind (Priv)); |
| |
| -- Also set Etype temporarily to Any_Type, again, in the absence |
| -- of errors, it will be properly reset, and if there are errors, |
| -- then we want a value of Any_Type to remain. |
| |
| Set_Etype (Full, Any_Type); |
| |
| -- Now start copying attributes |
| |
| Set_Has_Discriminants (Full, Has_Discriminants (Priv)); |
| |
| if Has_Discriminants (Full) then |
| Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv)); |
| Set_Stored_Constraint (Full, Stored_Constraint (Priv)); |
| end if; |
| |
| Set_First_Rep_Item (Full, First_Rep_Item (Priv)); |
| Set_Homonym (Full, Homonym (Priv)); |
| Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv)); |
| Set_Is_Public (Full, Is_Public (Priv)); |
| Set_Is_Pure (Full, Is_Pure (Priv)); |
| Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv)); |
| |
| Conditional_Delay (Full, Priv); |
| |
| if Is_Tagged_Type (Full) then |
| Set_Primitive_Operations (Full, Primitive_Operations (Priv)); |
| |
| if Priv = Base_Type (Priv) then |
| Set_Class_Wide_Type (Full, Class_Wide_Type (Priv)); |
| end if; |
| end if; |
| |
| Set_Is_Volatile (Full, Is_Volatile (Priv)); |
| Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv)); |
| Set_Scope (Full, Scope (Priv)); |
| Set_Next_Entity (Full, Next_Entity (Priv)); |
| Set_First_Entity (Full, First_Entity (Priv)); |
| Set_Last_Entity (Full, Last_Entity (Priv)); |
| |
| -- If access types have been recorded for later handling, keep them in |
| -- the full view so that they get handled when the full view freeze |
| -- node is expanded. |
| |
| if Present (Freeze_Node (Priv)) |
| and then Present (Access_Types_To_Process (Freeze_Node (Priv))) |
| then |
| Ensure_Freeze_Node (Full); |
| Set_Access_Types_To_Process |
| (Freeze_Node (Full), |
| Access_Types_To_Process (Freeze_Node (Priv))); |
| end if; |
| |
| -- Swap the two entities. Now Privat is the full type entity and |
| -- Full is the private one. They will be swapped back at the end |
| -- of the private part. This swapping ensures that the entity that |
| -- is visible in the private part is the full declaration. |
| |
| Exchange_Entities (Priv, Full); |
| Append_Entity (Full, Scope (Full)); |
| end Copy_And_Swap; |
| |
| ------------------------------------- |
| -- Copy_Array_Base_Type_Attributes -- |
| ------------------------------------- |
| |
| procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is |
| begin |
| Set_Component_Alignment (T1, Component_Alignment (T2)); |
| Set_Component_Type (T1, Component_Type (T2)); |
| Set_Component_Size (T1, Component_Size (T2)); |
| Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2)); |
| Set_Finalize_Storage_Only (T1, Finalize_Storage_Only (T2)); |
| Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2)); |
| Set_Has_Task (T1, Has_Task (T2)); |
| Set_Is_Packed (T1, Is_Packed (T2)); |
| Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2)); |
| Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2)); |
| Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2)); |
| end Copy_Array_Base_Type_Attributes; |
| |
| ----------------------------------- |
| -- Copy_Array_Subtype_Attributes -- |
| ----------------------------------- |
| |
| procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is |
| begin |
| Set_Size_Info (T1, T2); |
| |
| Set_First_Index (T1, First_Index (T2)); |
| Set_Is_Aliased (T1, Is_Aliased (T2)); |
| Set_Is_Atomic (T1, Is_Atomic (T2)); |
| Set_Is_Volatile (T1, Is_Volatile (T2)); |
| Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2)); |
| Set_Is_Constrained (T1, Is_Constrained (T2)); |
| Set_Depends_On_Private (T1, Has_Private_Component (T2)); |
| Set_First_Rep_Item (T1, First_Rep_Item (T2)); |
| Set_Convention (T1, Convention (T2)); |
| Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2)); |
| Set_Is_Private_Composite (T1, Is_Private_Composite (T2)); |
| end Copy_Array_Subtype_Attributes; |
| |
| ----------------------------------- |
| -- Create_Constrained_Components -- |
| ----------------------------------- |
| |
| procedure Create_Constrained_Components |
| (Subt : Entity_Id; |
| Decl_Node : Node_Id; |
| Typ : Entity_Id; |
| Constraints : Elist_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (Subt); |
| Comp_List : constant Elist_Id := New_Elmt_List; |
| Parent_Type : constant Entity_Id := Etype (Typ); |
| Assoc_List : constant List_Id := New_List; |
| Discr_Val : Elmt_Id; |
| Errors : Boolean; |
| New_C : Entity_Id; |
| Old_C : Entity_Id; |
| Is_Static : Boolean := True; |
| |
| procedure Collect_Fixed_Components (Typ : Entity_Id); |
| -- Collect parent type components that do not appear in a variant part |
| |
| procedure Create_All_Components; |
| -- Iterate over Comp_List to create the components of the subtype |
| |
| function Create_Component (Old_Compon : Entity_Id) return Entity_Id; |
| -- Creates a new component from Old_Compon, copying all the fields from |
| -- it, including its Etype, inserts the new component in the Subt entity |
| -- chain and returns the new component. |
| |
| function Is_Variant_Record (T : Entity_Id) return Boolean; |
| -- If true, and discriminants are static, collect only components from |
| -- variants selected by discriminant values. |
| |
| ------------------------------ |
| -- Collect_Fixed_Components -- |
| ------------------------------ |
| |
| procedure Collect_Fixed_Components (Typ : Entity_Id) is |
| begin |
| -- Build association list for discriminants, and find components of the |
| -- variant part selected by the values of the discriminants. |
| |
| Old_C := First_Discriminant (Typ); |
| Discr_Val := First_Elmt (Constraints); |
| while Present (Old_C) loop |
| Append_To (Assoc_List, |
| Make_Component_Association (Loc, |
| Choices => New_List (New_Occurrence_Of (Old_C, Loc)), |
| Expression => New_Copy (Node (Discr_Val)))); |
| |
| Next_Elmt (Discr_Val); |
| Next_Discriminant (Old_C); |
| end loop; |
| |
| -- The tag, and the possible parent and controller components |
| -- are unconditionally in the subtype. |
| |
| if Is_Tagged_Type (Typ) |
| or else Has_Controlled_Component (Typ) |
| then |
| Old_C := First_Component (Typ); |
| while Present (Old_C) loop |
| if Chars ((Old_C)) = Name_uTag |
| or else Chars ((Old_C)) = Name_uParent |
| or else Chars ((Old_C)) = Name_uController |
| then |
| Append_Elmt (Old_C, Comp_List); |
| end if; |
| |
| Next_Component (Old_C); |
| end loop; |
| end if; |
| end Collect_Fixed_Components; |
| |
| --------------------------- |
| -- Create_All_Components -- |
| --------------------------- |
| |
| procedure Create_All_Components is |
| Comp : Elmt_Id; |
| |
| begin |
| Comp := First_Elmt (Comp_List); |
| while Present (Comp) loop |
| Old_C := Node (Comp); |
| New_C := Create_Component (Old_C); |
| |
| Set_Etype |
| (New_C, |
| Constrain_Component_Type |
| (Old_C, Subt, Decl_Node, Typ, Constraints)); |
| Set_Is_Public (New_C, Is_Public (Subt)); |
| |
| Next_Elmt (Comp); |
| end loop; |
| end Create_All_Components; |
| |
| ---------------------- |
| -- Create_Component -- |
| ---------------------- |
| |
| function Create_Component (Old_Compon : Entity_Id) return Entity_Id is |
| New_Compon : constant Entity_Id := New_Copy (Old_Compon); |
| |
| begin |
| if Ekind (Old_Compon) = E_Discriminant |
| and then Is_Completely_Hidden (Old_Compon) |
| then |
| |
| -- This is a shadow discriminant created for a discriminant of |
| -- the parent type that is one of several renamed by the same |
| -- new discriminant. Give the shadow discriminant an internal |
| -- name that cannot conflict with that of visible components. |
| |
| Set_Chars (New_Compon, New_Internal_Name ('C')); |
| end if; |
| |
| -- Set the parent so we have a proper link for freezing etc. This is |
| -- not a real parent pointer, since of course our parent does not own |
| -- up to us and reference us, we are an illegitimate child of the |
| -- original parent! |
| |
| Set_Parent (New_Compon, Parent (Old_Compon)); |
| |
| -- If the old component's Esize was already determined and is a |
| -- static value, then the new component simply inherits it. Otherwise |
| -- the old component's size may require run-time determination, but |
| -- the new component's size still might be statically determinable |
| -- (if, for example it has a static constraint). In that case we want |
| -- Layout_Type to recompute the component's size, so we reset its |
| -- size and positional fields. |
| |
| if Frontend_Layout_On_Target |
| and then not Known_Static_Esize (Old_Compon) |
| then |
| Set_Esize (New_Compon, Uint_0); |
| Init_Normalized_First_Bit (New_Compon); |
| Init_Normalized_Position (New_Compon); |
| Init_Normalized_Position_Max (New_Compon); |
| end if; |
| |
| -- We do not want this node marked as Comes_From_Source, since |
| -- otherwise it would get first class status and a separate cross- |
| -- reference line would be generated. Illegitimate children do not |
| -- rate such recognition. |
| |
| Set_Comes_From_Source (New_Compon, False); |
| |
| -- But it is a real entity, and a birth certificate must be properly |
| -- registered by entering it into the entity list. |
| |
| Enter_Name (New_Compon); |
| |
| return New_Compon; |
| end Create_Component; |
| |
| ----------------------- |
| -- Is_Variant_Record -- |
| ----------------------- |
| |
| function Is_Variant_Record (T : Entity_Id) return Boolean is |
| begin |
| return Nkind (Parent (T)) = N_Full_Type_Declaration |
| and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition |
| and then Present (Component_List (Type_Definition (Parent (T)))) |
| and then Present ( |
| Variant_Part (Component_List (Type_Definition (Parent (T))))); |
| end Is_Variant_Record; |
| |
| -- Start of processing for Create_Constrained_Components |
| |
| begin |
| pragma Assert (Subt /= Base_Type (Subt)); |
| pragma Assert (Typ = Base_Type (Typ)); |
| |
| Set_First_Entity (Subt, Empty); |
| Set_Last_Entity (Subt, Empty); |
| |
| -- Check whether constraint is fully static, in which case we can |
| -- optimize the list of components. |
| |
| Discr_Val := First_Elmt (Constraints); |
| while Present (Discr_Val) loop |
| if not Is_OK_Static_Expression (Node (Discr_Val)) then |
| Is_Static := False; |
| exit; |
| end if; |
| |
| Next_Elmt (Discr_Val); |
| end loop; |
| |
| New_Scope (Subt); |
| |
| -- Inherit the discriminants of the parent type |
| |
| Add_Discriminants : declare |
| Num_Disc : Int; |
| Num_Gird : Int; |
| |
| begin |
| Num_Disc := 0; |
| Old_C := First_Discriminant (Typ); |
| |
| while Present (Old_C) loop |
| Num_Disc := Num_Disc + 1; |
| New_C := Create_Component (Old_C); |
| Set_Is_Public (New_C, Is_Public (Subt)); |
| Next_Discriminant (Old_C); |
| end loop; |
| |
| -- For an untagged derived subtype, the number of discriminants may |
| -- be smaller than the number of inherited discriminants, because |
| -- several of them may be renamed by a single new discriminant. |
| -- In this case, add the hidden discriminants back into the subtype, |
| -- because otherwise the size of the subtype is computed incorrectly |
| -- in GCC 4.1. |
| |
| Num_Gird := 0; |
| |
| if Is_Derived_Type (Typ) |
| and then not Is_Tagged_Type (Typ) |
| then |
| Old_C := First_Stored_Discriminant (Typ); |
| |
| while Present (Old_C) loop |
| Num_Gird := Num_Gird + 1; |
| Next_Stored_Discriminant (Old_C); |
| end loop; |
| end if; |
| |
| if Num_Gird > Num_Disc then |
| |
| -- Find out multiple uses of new discriminants, and add hidden |
| -- components for the extra renamed discriminants. We recognize |
| -- multiple uses through the Corresponding_Discriminant of a |
| -- new discriminant: if it constrains several old discriminants, |
| -- this field points to the last one in the parent type. The |
| -- stored discriminants of the derived type have the same name |
| -- as those of the parent. |
| |
| declare |
| Constr : Elmt_Id; |
| New_Discr : Entity_Id; |
| Old_Discr : Entity_Id; |
| |
| begin |
| Constr := First_Elmt (Stored_Constraint (Typ)); |
| Old_Discr := First_Stored_Discriminant (Typ); |
| |
| while Present (Constr) loop |
| if Is_Entity_Name (Node (Constr)) |
| and then Ekind (Entity (Node (Constr))) = E_Discriminant |
| then |
| New_Discr := Entity (Node (Constr)); |
| |
| if Chars (Corresponding_Discriminant (New_Discr)) |
| /= Chars (Old_Discr) |
| then |
| |
| -- The new discriminant has been used to rename |
| -- a subsequent old discriminant. Introduce a shadow |
| -- component for the current old discriminant. |
| |
| New_C := Create_Component (Old_Discr); |
| Set_Original_Record_Component (New_C, Old_Discr); |
| end if; |
| end if; |
| |
| Next_Elmt (Constr); |
| Next_Stored_Discriminant (Old_Discr); |
| end loop; |
| end; |
| end if; |
| end Add_Discriminants; |
| |
| if Is_Static |
| and then Is_Variant_Record (Typ) |
| then |
| Collect_Fixed_Components (Typ); |
| |
| Gather_Components ( |
| Typ, |
| Component_List (Type_Definition (Parent (Typ))), |
| Governed_By => Assoc_List, |
| Into => Comp_List, |
| Report_Errors => Errors); |
| pragma Assert (not Errors); |
| |
| Create_All_Components; |
| |
| -- If the subtype declaration is created for a tagged type derivation |
| -- with constraints, we retrieve the record definition of the parent |
| -- type to select the components of the proper variant. |
| |
| elsif Is_Static |
| and then Is_Tagged_Type (Typ) |
| and then Nkind (Parent (Typ)) = N_Full_Type_Declaration |
| and then |
| Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition |
| and then Is_Variant_Record (Parent_Type) |
| then |
| Collect_Fixed_Components (Typ); |
| |
| Gather_Components ( |
| Typ, |
| Component_List (Type_Definition (Parent (Parent_Type))), |
| Governed_By => Assoc_List, |
| Into => Comp_List, |
| Report_Errors => Errors); |
| pragma Assert (not Errors); |
| |
| -- If the tagged derivation has a type extension, collect all the |
| -- new components therein. |
| |
| if Present |
| (Record_Extension_Part (Type_Definition (Parent (Typ)))) |
| then |
| Old_C := First_Component (Typ); |
| while Present (Old_C) loop |
| if Original_Record_Component (Old_C) = Old_C |
| and then Chars (Old_C) /= Name_uTag |
| and then Chars (Old_C) /= Name_uParent |
| and then Chars (Old_C) /= Name_uController |
| then |
| Append_Elmt (Old_C, Comp_List); |
| end if; |
| |
| Next_Component (Old_C); |
| end loop; |
| end if; |
| |
| Create_All_Components; |
| |
| else |
| -- If discriminants are not static, or if this is a multi-level type |
| -- extension, we have to include all components of the parent type. |
| |
| Old_C := First_Component (Typ); |
| while Present (Old_C) loop |
| New_C := Create_Component (Old_C); |
| |
| Set_Etype |
| (New_C, |
| Constrain_Component_Type |
| (Old_C, Subt, Decl_Node, Typ, Constraints)); |
| Set_Is_Public (New_C, Is_Public (Subt)); |
| |
| Next_Component (Old_C); |
| end loop; |
| end if; |
| |
| End_Scope; |
| end Create_Constrained_Components; |
| |
| ------------------------------------------ |
| -- Decimal_Fixed_Point_Type_Declaration -- |
| ------------------------------------------ |
| |
| procedure Decimal_Fixed_Point_Type_Declaration |
| (T : Entity_Id; |
| Def : Node_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (Def); |
| Digs_Expr : constant Node_Id := Digits_Expression (Def); |
| Delta_Expr : constant Node_Id := Delta_Expression (Def); |
| Implicit_Base : Entity_Id; |
| Digs_Val : Uint; |
| Delta_Val : Ureal; |
| Scale_Val : Uint; |
| Bound_Val : Ureal; |
| |
| -- Start of processing for Decimal_Fixed_Point_Type_Declaration |
| |
| begin |
| Check_Restriction (No_Fixed_Point, Def); |
| |
| -- Create implicit base type |
| |
| Implicit_Base := |
| Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B'); |
| Set_Etype (Implicit_Base, Implicit_Base); |
| |
| -- Analyze and process delta expression |
| |
| Analyze_And_Resolve (Delta_Expr, Universal_Real); |
| |
| Check_Delta_Expression (Delta_Expr); |
| Delta_Val := Expr_Value_R (Delta_Expr); |
| |
| -- Check delta is power of 10, and determine scale value from it |
| |
| declare |
| Val : Ureal; |
| |
| begin |
| Scale_Val := Uint_0; |
| Val := Delta_Val; |
| |
| if Val < Ureal_1 then |
| while Val < Ureal_1 loop |
| Val := Val * Ureal_10; |
| Scale_Val := Scale_Val + 1; |
| end loop; |
| |
| if Scale_Val > 18 then |
| Error_Msg_N ("scale exceeds maximum value of 18", Def); |
| Scale_Val := UI_From_Int (+18); |
| end if; |
| |
| else |
| while Val > Ureal_1 loop |
| Val := Val / Ureal_10; |
| Scale_Val := Scale_Val - 1; |
| end loop; |
| |
| if Scale_Val < -18 then |
| Error_Msg_N ("scale is less than minimum value of -18", Def); |
| Scale_Val := UI_From_Int (-18); |
| end if; |
| end if; |
| |
| if Val /= Ureal_1 then |
| Error_Msg_N ("delta expression must be a power of 10", Def); |
| Delta_Val := Ureal_10 ** (-Scale_Val); |
| end if; |
| end; |
| |
| -- Set delta, scale and small (small = delta for decimal type) |
| |
| Set_Delta_Value (Implicit_Base, Delta_Val); |
| Set_Scale_Value (Implicit_Base, Scale_Val); |
| Set_Small_Value (Implicit_Base, Delta_Val); |
| |
| -- Analyze and process digits expression |
| |
| Analyze_And_Resolve (Digs_Expr, Any_Integer); |
| Check_Digits_Expression (Digs_Expr); |
| Digs_Val := Expr_Value (Digs_Expr); |
| |
| if Digs_Val > 18 then |
| Digs_Val := UI_From_Int (+18); |
| Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr); |
| end if; |
| |
| Set_Digits_Value (Implicit_Base, Digs_Val); |
| Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val; |
| |
| -- Set range of base type from digits value for now. This will be |
| -- expanded to represent the true underlying base range by Freeze. |
| |
| Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val); |
| |
| -- Set size to zero for now, size will be set at freeze time. We have |
| -- to do this for ordinary fixed-point, because the size depends on |
| -- the specified small, and we might as well do the same for decimal |
| -- fixed-point. |
| |
| Init_Size_Align (Implicit_Base); |
| |
| -- If there are bounds given in the declaration use them as the |
| -- bounds of the first named subtype. |
| |
| if Present (Real_Range_Specification (Def)) then |
| declare |
| RRS : constant Node_Id := Real_Range_Specification (Def); |
| Low : constant Node_Id := Low_Bound (RRS); |
| High : constant Node_Id := High_Bound (RRS); |
| Low_Val : Ureal; |
| High_Val : Ureal; |
| |
| begin |
| Analyze_And_Resolve (Low, Any_Real); |
| Analyze_And_Resolve (High, Any_Real); |
| Check_Real_Bound (Low); |
| Check_Real_Bound (High); |
| Low_Val := Expr_Value_R (Low); |
| High_Val := Expr_Value_R (High); |
| |
| if Low_Val < (-Bound_Val) then |
| Error_Msg_N |
| ("range low bound too small for digits value", Low); |
| Low_Val := -Bound_Val; |
| end if; |
| |
| if High_Val > Bound_Val then |
| Error_Msg_N |
| ("range high bound too large for digits value", High); |
| High_Val := Bound_Val; |
| end if; |
| |
| Set_Fixed_Range (T, Loc, Low_Val, High_Val); |
| end; |
| |
| -- If no explicit range, use range that corresponds to given |
| -- digits value. This will end up as the final range for the |
| -- first subtype. |
| |
| else |
| Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val); |
| end if; |
| |
| -- Complete entity for first subtype |
| |
| Set_Ekind (T, E_Decimal_Fixed_Point_Subtype); |
| Set_Etype (T, Implicit_Base); |
| Set_Size_Info (T, Implicit_Base); |
| Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base)); |
| Set_Digits_Value (T, Digs_Val); |
| Set_Delta_Value (T, Delta_Val); |
| Set_Small_Value (T, Delta_Val); |
| Set_Scale_Value (T, Scale_Val); |
| Set_Is_Constrained (T); |
| end Decimal_Fixed_Point_Type_Declaration; |
| |
| --------------------------------- |
| -- Derive_Interface_Subprogram -- |
| --------------------------------- |
| |
| procedure Derive_Interface_Subprograms (Derived_Type : Entity_Id) is |
| |
| procedure Do_Derivation (T : Entity_Id); |
| -- This inner subprograms is used to climb to the ancestors. |
| -- It is needed to add the derivations to the Derived_Type. |
| |
| procedure Do_Derivation (T : Entity_Id) is |
| Etyp : constant Entity_Id := Etype (T); |
| AI : Elmt_Id; |
| |
| begin |
| if Etyp /= T |
| and then Is_Interface (Etyp) |
| then |
| Do_Derivation (Etyp); |
| end if; |
| |
| if Present (Abstract_Interfaces (T)) |
| and then not Is_Empty_Elmt_List (Abstract_Interfaces (T)) |
| then |
| AI := First_Elmt (Abstract_Interfaces (T)); |
| while Present (AI) loop |
| if not Is_Ancestor (Node (AI), Derived_Type) then |
| Derive_Subprograms |
| (Parent_Type => Node (AI), |
| Derived_Type => Derived_Type, |
| No_Predefined_Prims => True); |
| end if; |
| |
| Next_Elmt (AI); |
| end loop; |
| end if; |
| end Do_Derivation; |
| |
| begin |
| Do_Derivation (Derived_Type); |
| |
| -- At this point the list of primitive operations of Derived_Type |
| -- contains the entities corresponding to all the subprograms of all the |
| -- implemented interfaces. If N interfaces have subprograms with the |
| -- same profile we have N entities in this list because each one must be |
| -- allocated in its corresponding virtual table. |
| |
| -- Its alias attribute references its original interface subprogram. |
| -- When overridden, the alias attribute is later saved in the |
| -- Abstract_Interface_Alias attribute. |
| |
| end Derive_Interface_Subprograms; |
| |
| ----------------------- |
| -- Derive_Subprogram -- |
| ----------------------- |
| |
| procedure Derive_Subprogram |
| (New_Subp : in out Entity_Id; |
| Parent_Subp : Entity_Id; |
| Derived_Type : Entity_Id; |
| Parent_Type : Entity_Id; |
| Actual_Subp : Entity_Id := Empty) |
| is |
| Formal : Entity_Id; |
| New_Formal : Entity_Id; |
| Visible_Subp : Entity_Id := Parent_Subp; |
| |
| function Is_Private_Overriding return Boolean; |
| -- If Subp is a private overriding of a visible operation, the in- |
| -- herited operation derives from the overridden op (even though |
| -- its body is the overriding one) and the inherited operation is |
| -- visible now. See sem_disp to see the details of the handling of |
| -- the overridden subprogram, which is removed from the list of |
| -- primitive operations of the type. The overridden subprogram is |
| -- saved locally in Visible_Subp, and used to diagnose abstract |
| -- operations that need overriding in the derived type. |
| |
| procedure Replace_Type (Id, New_Id : Entity_Id); |
| -- When the type is an anonymous access type, create a new access type |
| -- designating the derived type. |
| |
| procedure Set_Derived_Name; |
| -- This procedure sets the appropriate Chars name for New_Subp. This |
| -- is normally just a copy of the parent name. An exception arises for |
| -- type support subprograms, where the name is changed to reflect the |
| -- name of the derived type, e.g. if type foo is derived from type bar, |
| -- then a procedure barDA is derived with a name fooDA. |
| |
| --------------------------- |
| -- Is_Private_Overriding -- |
| --------------------------- |
| |
| function Is_Private_Overriding return Boolean is |
| Prev : Entity_Id; |
| |
| begin |
| -- The visible operation that is overridden is a homonym of the |
| -- parent subprogram. We scan the homonym chain to find the one |
| -- whose alias is the subprogram we are deriving. |
| |
| Prev := Current_Entity (Parent_Subp); |
| while Present (Prev) loop |
| if Is_Dispatching_Operation (Parent_Subp) |
| and then Present (Prev) |
| and then Ekind (Prev) = Ekind (Parent_Subp) |
| and then Alias (Prev) = Parent_Subp |
| and then Scope (Parent_Subp) = Scope (Prev) |
| and then |
| (not Is_Hidden (Prev) |
| or else |
| |
| -- Ada 2005 (AI-251): Entities associated with overridden |
| -- interface subprograms are always marked as hidden; in |
| -- this case the field abstract_interface_alias references |
| -- the original entity (cf. override_dispatching_operation). |
| |
| (Atree.Present (Abstract_Interface_Alias (Prev)) |
| and then not Is_Hidden (Abstract_Interface_Alias (Prev)))) |
| then |
| Visible_Subp := Prev; |
| return True; |
| end if; |
| |
| Prev := Homonym (Prev); |
| end loop; |
| |
| return False; |
| end Is_Private_Overriding; |
| |
| ------------------ |
| -- Replace_Type -- |
| ------------------ |
| |
| procedure Replace_Type (Id, New_Id : Entity_Id) is |
| Acc_Type : Entity_Id; |
| IR : Node_Id; |
| Par : constant Node_Id := Parent (Derived_Type); |
| |
| begin |
| -- When the type is an anonymous access type, create a new access |
| -- type designating the derived type. This itype must be elaborated |
| -- at the point of the derivation, not on subsequent calls that may |
| -- be out of the proper scope for Gigi, so we insert a reference to |
| -- it after the derivation. |
| |
| if Ekind (Etype (Id)) = E_Anonymous_Access_Type then |
| declare |
| Desig_Typ : Entity_Id := Designated_Type (Etype (Id)); |
| |
| begin |
| if Ekind (Desig_Typ) = E_Record_Type_With_Private |
| and then Present (Full_View (Desig_Typ)) |
| and then not Is_Private_Type (Parent_Type) |
| then |
| Desig_Typ := Full_View (Desig_Typ); |
| end if; |
| |
| if Base_Type (Desig_Typ) = Base_Type (Parent_Type) then |
| Acc_Type := New_Copy (Etype (Id)); |
| Set_Etype (Acc_Type, Acc_Type); |
| Set_Scope (Acc_Type, New_Subp); |
| |
| -- Compute size of anonymous access type |
| |
| if Is_Array_Type (Desig_Typ) |
| and then not Is_Constrained (Desig_Typ) |
| then |
| Init_Size (Acc_Type, 2 * System_Address_Size); |
| else |
| Init_Size (Acc_Type, System_Address_Size); |
| end if; |
| |
| Init_Alignment (Acc_Type); |
| Set_Directly_Designated_Type (Acc_Type, Derived_Type); |
| |
| Set_Etype (New_Id, Acc_Type); |
| Set_Scope (New_Id, New_Subp); |
| |
| -- Create a reference to it |
| |
| IR := Make_Itype_Reference (Sloc (Parent (Derived_Type))); |
| Set_Itype (IR, Acc_Type); |
| Insert_After (Parent (Derived_Type), IR); |
| |
| else |
| Set_Etype (New_Id, Etype (Id)); |
| end if; |
| end; |
| |
| elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type) |
| or else |
| (Ekind (Etype (Id)) = E_Record_Type_With_Private |
| and then Present (Full_View (Etype (Id))) |
| and then |
| Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type)) |
| then |
| -- Constraint checks on formals are generated during expansion, |
| -- based on the signature of the original subprogram. The bounds |
| -- of the derived type are not relevant, and thus we can use |
| -- the base type for the formals. However, the return type may be |
| -- used in a context that requires that the proper static bounds |
| -- be used (a case statement, for example) and for those cases |
| -- we must use the derived type (first subtype), not its base. |
| |
| -- If the derived_type_definition has no constraints, we know that |
| -- the derived type has the same constraints as the first subtype |
| -- of the parent, and we can also use it rather than its base, |
| -- which can lead to more efficient code. |
| |
| if Etype (Id) = Parent_Type then |
| if Is_Scalar_Type (Parent_Type) |
| and then |
| Subtypes_Statically_Compatible (Parent_Type, Derived_Type) |
| then |
| Set_Etype (New_Id, Derived_Type); |
| |
| elsif Nkind (Par) = N_Full_Type_Declaration |
| and then |
| Nkind (Type_Definition (Par)) = N_Derived_Type_Definition |
| and then |
| Is_Entity_Name |
| (Subtype_Indication (Type_Definition (Par))) |
| then |
| Set_Etype (New_Id, Derived_Type); |
| |
| else |
| Set_Etype (New_Id, Base_Type (Derived_Type)); |
| end if; |
| |
| else |
| Set_Etype (New_Id, Base_Type (Derived_Type)); |
| end if; |
| |
| else |
| Set_Etype (New_Id, Etype (Id)); |
| end if; |
| end Replace_Type; |
| |
| ---------------------- |
| -- Set_Derived_Name -- |
| ---------------------- |
| |
| procedure Set_Derived_Name is |
| Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp); |
| begin |
| if Nm = TSS_Null then |
| Set_Chars (New_Subp, Chars (Parent_Subp)); |
| else |
| Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm)); |
| end if; |
| end Set_Derived_Name; |
| |
| -- Start of processing for Derive_Subprogram |
| |
| begin |
| New_Subp := |
| New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type)); |
| Set_Ekind (New_Subp, Ekind (Parent_Subp)); |
| |
| -- Check whether the inherited subprogram is a private operation that |
| -- should be inherited but not yet made visible. Such subprograms can |
| -- become visible at a later point (e.g., the private part of a public |
| -- child unit) via Declare_Inherited_Private_Subprograms. If the |
| -- following predicate is true, then this is not such a private |
| -- operation and the subprogram simply inherits the name of the parent |
| -- subprogram. Note the special check for the names of controlled |
| -- operations, which are currently exempted from being inherited with |
| -- a hidden name because they must be findable for generation of |
| -- implicit run-time calls. |
| |
| if not Is_Hidden (Parent_Subp) |
| or else Is_Internal (Parent_Subp) |
| or else Is_Private_Overriding |
| or else Is_Internal_Name (Chars (Parent_Subp)) |
| or else Chars (Parent_Subp) = Name_Initialize |
| or else Chars (Parent_Subp) = Name_Adjust |
| or else Chars (Parent_Subp) = Name_Finalize |
| then |
| Set_Derived_Name; |
| |
| -- If parent is hidden, this can be a regular derivation if the |
| -- parent is immediately visible in a non-instantiating context, |
| -- or if we are in the private part of an instance. This test |
| -- should still be refined ??? |
| |
| -- The test for In_Instance_Not_Visible avoids inheriting the derived |
| -- operation as a non-visible operation in cases where the parent |
| -- subprogram might not be visible now, but was visible within the |
| -- original generic, so it would be wrong to make the inherited |
| -- subprogram non-visible now. (Not clear if this test is fully |
| -- correct; are there any cases where we should declare the inherited |
| -- operation as not visible to avoid it being overridden, e.g., when |
| -- the parent type is a generic actual with private primitives ???) |
| |
| -- (they should be treated the same as other private inherited |
| -- subprograms, but it's not clear how to do this cleanly). ??? |
| |
| elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type))) |
| and then Is_Immediately_Visible (Parent_Subp) |
| and then not In_Instance) |
| or else In_Instance_Not_Visible |
| then |
| Set_Derived_Name; |
| |
| -- The type is inheriting a private operation, so enter |
| -- it with a special name so it can't be overridden. |
| |
| else |
| Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P')); |
| end if; |
| |
| Set_Parent (New_Subp, Parent (Derived_Type)); |
| Replace_Type (Parent_Subp, New_Subp); |
| Conditional_Delay (New_Subp, Parent_Subp); |
| |
| Formal := First_Formal (Parent_Subp); |
| while Present (Formal) loop |
| New_Formal := New_Copy (Formal); |
| |
| -- Normally we do not go copying parents, but in the case of |
| -- formals, we need to link up to the declaration (which is the |
| -- parameter specification), and it is fine to link up to the |
| -- original formal's parameter specification in this case. |
| |
| Set_Parent (New_Formal, Parent (Formal)); |
| |
| Append_Entity (New_Formal, New_Subp); |
| |
| Replace_Type (Formal, New_Formal); |
| Next_Formal (Formal); |
| end loop; |
| |
| -- If this derivation corresponds to a tagged generic actual, then |
| -- primitive operations rename those of the actual. Otherwise the |
| -- primitive operations rename those of the parent type, If the |
| -- parent renames an intrinsic operator, so does the new subprogram. |
| -- We except concatenation, which is always properly typed, and does |
| -- not get expanded as other intrinsic operations. |
| |
| if No (Actual_Subp) then |
| if Is_Intrinsic_Subprogram (Parent_Subp) then |
| Set_Is_Intrinsic_Subprogram (New_Subp); |
| |
| if Present (Alias (Parent_Subp)) |
| and then Chars (Parent_Subp) /= Name_Op_Concat |
| then |
| Set_Alias (New_Subp, Alias (Parent_Subp)); |
| else |
| Set_Alias (New_Subp, Parent_Subp); |
| end if; |
| |
| else |
| Set_Alias (New_Subp, Parent_Subp); |
| end if; |
| |
| else |
| Set_Alias (New_Subp, Actual_Subp); |
| end if; |
| |
| -- Derived subprograms of a tagged type must inherit the convention |
| -- of the parent subprogram (a requirement of AI-117). Derived |
| -- subprograms of untagged types simply get convention Ada by default. |
| |
| if Is_Tagged_Type (Derived_Type) then |
| Set_Convention (New_Subp, Convention (Parent_Subp)); |
| end if; |
| |
| Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp)); |
| Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp)); |
| |
| if Ekind (Parent_Subp) = E_Procedure then |
| Set_Is_Valued_Procedure |
| (New_Subp, Is_Valued_Procedure (Parent_Subp)); |
| end if; |
| |
| -- No_Return must be inherited properly. If this is overridden in the |
| -- case of a dispatching operation, then a check is made in Sem_Disp |
| -- that the overriding operation is also No_Return (no such check is |
| -- required for the case of non-dispatching operation. |
| |
| Set_No_Return (New_Subp, No_Return (Parent_Subp)); |
| |
| -- A derived function with a controlling result is abstract. If the |
| -- Derived_Type is a nonabstract formal generic derived type, then |
| -- inherited operations are not abstract: the required check is done at |
| -- instantiation time. If the derivation is for a generic actual, the |
| -- function is not abstract unless the actual is. |
| |
| if Is_Generic_Type (Derived_Type) |
| and then not Is_Abstract (Derived_Type) |
| then |
| null; |
| |
| elsif Is_Abstract (Alias (New_Subp)) |
| or else (Is_Tagged_Type (Derived_Type) |
| and then Etype (New_Subp) = Derived_Type |
| and then No (Actual_Subp)) |
| then |
| Set_Is_Abstract (New_Subp); |
| |
| -- Finally, if the parent type is abstract we must verify that all |
| -- inherited operations are either non-abstract or overridden, or |
| -- that the derived type itself is abstract (this check is performed |
| -- at the end of a package declaration, in Check_Abstract_Overriding). |
| -- A private overriding in the parent type will not be visible in the |
| -- derivation if we are not in an inner package or in a child unit of |
| -- the parent type, in which case the abstractness of the inherited |
| -- operation is carried to the new subprogram. |
| |
| elsif Is_Abstract (Parent_Type) |
| and then not In_Open_Scopes (Scope (Parent_Type)) |
| and then Is_Private_Overriding |
| and then Is_Abstract (Visible_Subp) |
| then |
| Set_Alias (New_Subp, Visible_Subp); |
| Set_Is_Abstract (New_Subp); |
| end if; |
| |
| New_Overloaded_Entity (New_Subp, Derived_Type); |
| |
| -- Check for case of a derived subprogram for the instantiation of a |
| -- formal derived tagged type, if so mark the subprogram as dispatching |
| -- and inherit the dispatching attributes of the parent subprogram. The |
| -- derived subprogram is effectively renaming of the actual subprogram, |
| -- so it needs to have the same attributes as the actual. |
| |
| if Present (Actual_Subp) |
| and then Is_Dispatching_Operation (Parent_Subp) |
| then |
| Set_Is_Dispatching_Operation (New_Subp); |
| if Present (DTC_Entity (Parent_Subp)) then |
| Set_DTC_Entity (New_Subp, DTC_Entity (Parent_Subp)); |
| Set_DT_Position (New_Subp, DT_Position (Parent_Subp)); |
| end if; |
| end if; |
| |
| -- Indicate that a derived subprogram does not require a body and that |
| -- it does not require processing of default expressions. |
| |
| Set_Has_Completion (New_Subp); |
| Set_Default_Expressions_Processed (New_Subp); |
| |
| if Ekind (New_Subp) = E_Function then |
| Set_Mechanism (New_Subp, Mechanism (Parent_Subp)); |
| end if; |
| end Derive_Subprogram; |
| |
| ------------------------ |
| -- Derive_Subprograms -- |
| ------------------------ |
| |
| procedure Derive_Subprograms |
| (Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id; |
| Generic_Actual : Entity_Id := Empty; |
| No_Predefined_Prims : Boolean := False) |
| is |
| Op_List : constant Elist_Id := |
| Collect_Primitive_Operations (Parent_Type); |
| Act_List : Elist_Id; |
| Act_Elmt : Elmt_Id; |
| Elmt : Elmt_Id; |
| Is_Predef : Boolean; |
| Subp : Entity_Id; |
| New_Subp : Entity_Id := Empty; |
| Parent_Base : Entity_Id; |
| |
| begin |
| if Ekind (Parent_Type) = E_Record_Type_With_Private |
| and then Has_Discriminants (Parent_Type) |
| and then Present (Full_View (Parent_Type)) |
| then |
| Parent_Base := Full_View (Parent_Type); |
| else |
| Parent_Base := Parent_Type; |
| end if; |
| |
| if Present (Generic_Actual) then |
| Act_List := Collect_Primitive_Operations (Generic_Actual); |
| Act_Elmt := First_Elmt (Act_List); |
| else |
| Act_Elmt := No_Elmt; |
| end if; |
| |
| -- Literals are derived earlier in the process of building the derived |
| -- type, and are skipped here. |
| |
| Elmt := First_Elmt (Op_List); |
| while Present (Elmt) loop |
| Subp := Node (Elmt); |
| |
| if Ekind (Subp) /= E_Enumeration_Literal then |
| Is_Predef := |
| Is_Dispatching_Operation (Subp) |
| and then Is_Predefined_Dispatching_Operation (Subp); |
| |
| if No_Predefined_Prims and then Is_Predef then |
| null; |
| |
| -- We don't need to derive alias entities associated with |
| -- abstract interfaces |
| |
| elsif Is_Dispatching_Operation (Subp) |
| and then Present (Alias (Subp)) |
| and then Present (Abstract_Interface_Alias (Subp)) |
| then |
| null; |
| |
| elsif No (Generic_Actual) then |
| Derive_Subprogram |
| (New_Subp, Subp, Derived_Type, Parent_Base); |
| |
| else |
| Derive_Subprogram (New_Subp, Subp, |
| Derived_Type, Parent_Base, Node (Act_Elmt)); |
| Next_Elmt (Act_Elmt); |
| end if; |
| end if; |
| |
| Next_Elmt (Elmt); |
| end loop; |
| end Derive_Subprograms; |
| |
| -------------------------------- |
| -- Derived_Standard_Character -- |
| -------------------------------- |
| |
| procedure Derived_Standard_Character |
| (N : Node_Id; |
| Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| Def : constant Node_Id := Type_Definition (N); |
| Indic : constant Node_Id := Subtype_Indication (Def); |
| Parent_Base : constant Entity_Id := Base_Type (Parent_Type); |
| Implicit_Base : constant Entity_Id := |
| Create_Itype |
| (E_Enumeration_Type, N, Derived_Type, 'B'); |
| |
| Lo : Node_Id; |
| Hi : Node_Id; |
| |
| begin |
| Discard_Node (Process_Subtype (Indic, N)); |
| |
| Set_Etype (Implicit_Base, Parent_Base); |
| Set_Size_Info (Implicit_Base, Root_Type (Parent_Type)); |
| Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type))); |
| |
| Set_Is_Character_Type (Implicit_Base, True); |
| Set_Has_Delayed_Freeze (Implicit_Base); |
| |
| -- The bounds of the implicit base are the bounds of the parent base. |
| -- Note that their type is the parent base. |
| |
| Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base)); |
| Hi := New_Copy_Tree (Type_High_Bound (Parent_Base)); |
| |
| Set_Scalar_Range (Implicit_Base, |
| Make_Range (Loc, |
| Low_Bound => Lo, |
| High_Bound => Hi)); |
| |
| Conditional_Delay (Derived_Type, Parent_Type); |
| |
| Set_Ekind (Derived_Type, E_Enumeration_Subtype); |
| Set_Etype (Derived_Type, Implicit_Base); |
| Set_Size_Info (Derived_Type, Parent_Type); |
| |
| if Unknown_RM_Size (Derived_Type) then |
| Set_RM_Size (Derived_Type, RM_Size (Parent_Type)); |
| end if; |
| |
| Set_Is_Character_Type (Derived_Type, True); |
| |
| if Nkind (Indic) /= N_Subtype_Indication then |
| |
| -- If no explicit constraint, the bounds are those |
| -- of the parent type. |
| |
| Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type)); |
| Hi := New_Copy_Tree (Type_High_Bound (Parent_Type)); |
| Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi)); |
| end if; |
| |
| Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc); |
| |
| -- Because the implicit base is used in the conversion of the bounds, |
| -- we have to freeze it now. This is similar to what is done for |
| -- numeric types, and it equally suspicious, but otherwise a non- |
| -- static bound will have a reference to an unfrozen type, which is |
| -- rejected by Gigi (???). |
| |
| Freeze_Before (N, Implicit_Base); |
| end Derived_Standard_Character; |
| |
| ------------------------------ |
| -- Derived_Type_Declaration -- |
| ------------------------------ |
| |
| procedure Derived_Type_Declaration |
| (T : Entity_Id; |
| N : Node_Id; |
| Is_Completion : Boolean) |
| is |
| Def : constant Node_Id := Type_Definition (N); |
| Iface_Def : Node_Id; |
| Indic : constant Node_Id := Subtype_Indication (Def); |
| Extension : constant Node_Id := Record_Extension_Part (Def); |
| Parent_Type : Entity_Id; |
| Parent_Scope : Entity_Id; |
| Taggd : Boolean; |
| |
| function Comes_From_Generic (Typ : Entity_Id) return Boolean; |
| -- Check whether the parent type is a generic formal, or derives |
| -- directly or indirectly from one. |
| |
| ------------------------ |
| -- Comes_From_Generic -- |
| ------------------------ |
| |
| function Comes_From_Generic (Typ : Entity_Id) return Boolean is |
| begin |
| if Is_Generic_Type (Typ) then |
| return True; |
| |
| elsif Is_Generic_Type (Root_Type (Parent_Type)) then |
| return True; |
| |
| elsif Is_Private_Type (Typ) |
| and then Present (Full_View (Typ)) |
| and then Is_Generic_Type (Root_Type (Full_View (Typ))) |
| then |
| return True; |
| |
| elsif Is_Generic_Actual_Type (Typ) then |
| return True; |
| |
| else |
| return False; |
| end if; |
| end Comes_From_Generic; |
| |
| -- Start of processing for Derived_Type_Declaration |
| |
| begin |
| Parent_Type := Find_Type_Of_Subtype_Indic (Indic); |
| |
| -- Ada 2005 (AI-251): In case of interface derivation check that the |
| -- parent is also an interface. |
| |
| if Interface_Present (Def) then |
| if not Is_Interface (Parent_Type) then |
| Error_Msg_NE ("(Ada 2005) & must be an interface", |
| Indic, Parent_Type); |
| |
| else |
| Iface_Def := Type_Definition (Parent (Parent_Type)); |
| |
| -- Ada 2005 (AI-251): Limited interfaces can only inherit from |
| -- other limited interfaces. |
| |
| if Limited_Present (Def) then |
| if Limited_Present (Iface_Def) then |
| null; |
| |
| elsif Protected_Present (Iface_Def) then |
| Error_Msg_N ("(Ada 2005) limited interface cannot" & |
| " inherit from protected interface", Indic); |
| |
| elsif Synchronized_Present (Iface_Def) then |
| Error_Msg_N ("(Ada 2005) limited interface cannot" & |
| " inherit from synchronized interface", Indic); |
| |
| elsif Task_Present (Iface_Def) then |
| Error_Msg_N ("(Ada 2005) limited interface cannot" & |
| " inherit from task interface", Indic); |
| |
| else |
| Error_Msg_N ("(Ada 2005) limited interface cannot" & |
| " inherit from non-limited interface", Indic); |
| end if; |
| |
| -- Ada 2005 (AI-345): Non-limited interfaces can only inherit |
| -- from non-limited or limited interfaces. |
| |
| elsif not Protected_Present (Def) |
| and then not Synchronized_Present (Def) |
| and then not Task_Present (Def) |
| then |
| if Limited_Present (Iface_Def) then |
| null; |
| |
| elsif Protected_Present (Iface_Def) then |
| Error_Msg_N ("(Ada 2005) non-limited interface cannot" & |
| " inherit from protected interface", Indic); |
| |
| elsif Synchronized_Present (Iface_Def) then |
| Error_Msg_N ("(Ada 2005) non-limited interface cannot" & |
| " inherit from synchronized interface", Indic); |
| |
| elsif Task_Present (Iface_Def) then |
| Error_Msg_N ("(Ada 2005) non-limited interface cannot" & |
| " inherit from task interface", Indic); |
| |
| else |
| null; |
| end if; |
| end if; |
| end if; |
| end if; |
| |
| -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor |
| -- interfaces |
| |
| if Is_Tagged_Type (Parent_Type) |
| and then Is_Non_Empty_List (Interface_List (Def)) |
| then |
| declare |
| Intf : Node_Id; |
| T : Entity_Id; |
| |
| begin |
| Intf := First (Interface_List (Def)); |
| while Present (Intf) loop |
| T := Find_Type_Of_Subtype_Indic (Intf); |
| |
| if not Is_Interface (T) then |
| Error_Msg_NE ("(Ada 2005) & must be an interface", Intf, T); |
| |
| elsif Limited_Present (Def) |
| and then not Is_Limited_Interface (T) |
| then |
| Error_Msg_NE |
| ("progenitor interface& of limited type must be limited", |
| N, T); |
| end if; |
| |
| Next (Intf); |
| end loop; |
| end; |
| end if; |
| |
| if Parent_Type = Any_Type |
| or else Etype (Parent_Type) = Any_Type |
| or else (Is_Class_Wide_Type (Parent_Type) |
| and then Etype (Parent_Type) = T) |
| then |
| -- If Parent_Type is undefined or illegal, make new type into a |
| -- subtype of Any_Type, and set a few attributes to prevent cascaded |
| -- errors. If this is a self-definition, emit error now. |
| |
| if T = Parent_Type |
| or else T = Etype (Parent_Type) |
| then |
| Error_Msg_N ("type cannot be used in its own definition", Indic); |
| end if; |
| |
| Set_Ekind (T, Ekind (Parent_Type)); |
| Set_Etype (T, Any_Type); |
| Set_Scalar_Range (T, Scalar_Range (Any_Type)); |
| |
| if Is_Tagged_Type (T) then |
| Set_Primitive_Operations (T, New_Elmt_List); |
| end if; |
| |
| return; |
| end if; |
| |
| -- Ada 2005 (AI-251): The case in which the parent of the full-view is |
| -- an interface is special because the list of interfaces in the full |
| -- view can be given in any order. For example: |
| |
| -- type A is interface; |
| -- type B is interface and A; |
| -- type D is new B with private; |
| -- private |
| -- type D is new A and B with null record; -- 1 -- |
| |
| -- In this case we perform the following transformation of -1-: |
| |
| -- type D is new B and A with null record; |
| |
| -- If the parent of the full-view covers the parent of the partial-view |
| -- we have two possible cases: |
| |
| -- 1) They have the same parent |
| -- 2) The parent of the full-view implements some further interfaces |
| |
| -- In both cases we do not need to perform the transformation. In the |
| -- first case the source program is correct and the transformation is |
| -- not needed; in the second case the source program does not fulfill |
| -- the no-hidden interfaces rule (AI-396) and the error will be reported |
| -- later. |
| |
| -- This transformation not only simplifies the rest of the analysis of |
| -- this type declaration but also simplifies the correct generation of |
| -- the object layout to the expander. |
| |
| if In_Private_Part (Current_Scope) |
| and then Is_Interface (Parent_Type) |
| then |
| declare |
| Iface : Node_Id; |
| Partial_View : Entity_Id; |
| Partial_View_Parent : Entity_Id; |
| New_Iface : Node_Id; |
| |
| begin |
| -- Look for the associated private type declaration |
| |
| Partial_View := First_Entity (Current_Scope); |
| loop |
| exit when No (Partial_View) |
| or else (Has_Private_Declaration (Partial_View) |
| and then Full_View (Partial_View) = T); |
| |
| Next_Entity (Partial_View); |
| end loop; |
| |
| -- If the partial view was not found then the source code has |
| -- errors and the transformation is not needed. |
| |
| if Present (Partial_View) then |
| Partial_View_Parent := Etype (Partial_View); |
| |
| -- If the parent of the full-view covers the parent of the |
| -- partial-view we have nothing else to do. |
| |
| if Interface_Present_In_Ancestor |
| (Parent_Type, Partial_View_Parent) |
| then |
| null; |
| |
| -- Traverse the list of interfaces of the full-view to look |
| -- for the parent of the partial-view and perform the tree |
| -- transformation. |
| |
| else |
| Iface := First (Interface_List (Def)); |
| while Present (Iface) loop |
| if Etype (Iface) = Etype (Partial_View) then |
| Rewrite (Subtype_Indication (Def), |
| New_Copy (Subtype_Indication |
| (Parent (Partial_View)))); |
| |
| New_Iface := Make_Identifier (Sloc (N), |
| Chars (Parent_Type)); |
| Append (New_Iface, Interface_List (Def)); |
| |
| -- Analyze the transformed code |
| |
| Derived_Type_Declaration (T, N, Is_Completion); |
| return; |
| end if; |
| |
| Next (Iface); |
| end loop; |
| end if; |
| end if; |
| end; |
| end if; |
| |
| -- Only composite types other than array types are allowed to have |
| -- discriminants. |
| |
| if Present (Discriminant_Specifications (N)) |
| and then (Is_Elementary_Type (Parent_Type) |
| or else Is_Array_Type (Parent_Type)) |
| and then not Error_Posted (N) |
| then |
| Error_Msg_N |
| ("elementary or array type cannot have discriminants", |
| Defining_Identifier (First (Discriminant_Specifications (N)))); |
| Set_Has_Discriminants (T, False); |
| end if; |
| |
| -- In Ada 83, a derived type defined in a package specification cannot |
| -- be used for further derivation until the end of its visible part. |
| -- Note that derivation in the private part of the package is allowed. |
| |
| if Ada_Version = Ada_83 |
| and then Is_Derived_Type (Parent_Type) |
| and then In_Visible_Part (Scope (Parent_Type)) |
| then |
| if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then |
| Error_Msg_N |
| ("(Ada 83): premature use of type for derivation", Indic); |
| end if; |
| end if; |
| |
| -- Check for early use of incomplete or private type |
| |
| if Ekind (Parent_Type) = E_Void |
| or else Ekind (Parent_Type) = E_Incomplete_Type |
| then |
| Error_Msg_N ("premature derivation of incomplete type", Indic); |
| return; |
| |
| elsif (Is_Incomplete_Or_Private_Type (Parent_Type) |
| and then not Comes_From_Generic (Parent_Type)) |
| or else Has_Private_Component (Parent_Type) |
| then |
| -- The ancestor type of a formal type can be incomplete, in which |
| -- case only the operations of the partial view are available in |
| -- the generic. Subsequent checks may be required when the full |
| -- view is analyzed, to verify that derivation from a tagged type |
| -- has an extension. |
| |
| if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then |
| null; |
| |
| elsif No (Underlying_Type (Parent_Type)) |
| or else Has_Private_Component (Parent_Type) |
| then |
| Error_Msg_N |
| ("premature derivation of derived or private type", Indic); |
| |
| -- Flag the type itself as being in error, this prevents some |
| -- nasty problems with subsequent uses of the malformed type. |
| |
| Set_Error_Posted (T); |
| |
| -- Check that within the immediate scope of an untagged partial |
| -- view it's illegal to derive from the partial view if the |
| -- full view is tagged. (7.3(7)) |
| |
| -- We verify that the Parent_Type is a partial view by checking |
| -- that it is not a Full_Type_Declaration (i.e. a private type or |
| -- private extension declaration), to distinguish a partial view |
| -- from a derivation from a private type which also appears as |
| -- E_Private_Type. |
| |
| elsif Present (Full_View (Parent_Type)) |
| and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration |
| and then not Is_Tagged_Type (Parent_Type) |
| and then Is_Tagged_Type (Full_View (Parent_Type)) |
| then |
| Parent_Scope := Scope (T); |
| while Present (Parent_Scope) |
| and then Parent_Scope /= Standard_Standard |
| loop |
| if Parent_Scope = Scope (Parent_Type) then |
| Error_Msg_N |
| ("premature derivation from type with tagged full view", |
| Indic); |
| end if; |
| |
| Parent_Scope := Scope (Parent_Scope); |
| end loop; |
| end if; |
| end if; |
| |
| -- Check that form of derivation is appropriate |
| |
| Taggd := Is_Tagged_Type (Parent_Type); |
| |
| -- Perhaps the parent type should be changed to the class-wide type's |
| -- specific type in this case to prevent cascading errors ??? |
| |
| if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then |
| Error_Msg_N ("parent type must not be a class-wide type", Indic); |
| return; |
| end if; |
| |
| if Present (Extension) and then not Taggd then |
| Error_Msg_N |
| ("type derived from untagged type cannot have extension", Indic); |
| |
| elsif No (Extension) and then Taggd then |
| |
| -- If this declaration is within a private part (or body) of a |
| -- generic instantiation then the derivation is allowed (the parent |
| -- type can only appear tagged in this case if it's a generic actual |
| -- type, since it would otherwise have been rejected in the analysis |
| -- of the generic template). |
| |
| if not Is_Generic_Actual_Type (Parent_Type) |
| or else In_Visible_Part (Scope (Parent_Type)) |
| then |
| Error_Msg_N |
| ("type derived from tagged type must have extension", Indic); |
| end if; |
| end if; |
| |
| Build_Derived_Type (N, Parent_Type, T, Is_Completion); |
| |
| -- AI-419: the parent type of an explicitly limited derived type must |
| -- be a limited type or a limited interface. |
| |
| if Limited_Present (Def) then |
| Set_Is_Limited_Record (T); |
| |
| if Is_Interface (T) then |
| Set_Is_Limited_Interface (T); |
| end if; |
| |
| if not Is_Limited_Type (Parent_Type) |
| and then |
| (not Is_Interface (Parent_Type) |
| or else not Is_Limited_Interface (Parent_Type)) |
| then |
| Error_Msg_NE ("parent type& of limited type must be limited", |
| N, Parent_Type); |
| end if; |
| end if; |
| end Derived_Type_Declaration; |
| |
| ---------------------------------- |
| -- Enumeration_Type_Declaration -- |
| ---------------------------------- |
| |
| procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is |
| Ev : Uint; |
| L : Node_Id; |
| R_Node : Node_Id; |
| B_Node : Node_Id; |
| |
| begin |
| -- Create identifier node representing lower bound |
| |
| B_Node := New_Node (N_Identifier, Sloc (Def)); |
| L := First (Literals (Def)); |
| Set_Chars (B_Node, Chars (L)); |
| Set_Entity (B_Node, L); |
| Set_Etype (B_Node, T); |
| Set_Is_Static_Expression (B_Node, True); |
| |
| R_Node := New_Node (N_Range, Sloc (Def)); |
| Set_Low_Bound (R_Node, B_Node); |
| |
| Set_Ekind (T, E_Enumeration_Type); |
| Set_First_Literal (T, L); |
| Set_Etype (T, T); |
| Set_Is_Constrained (T); |
| |
| Ev := Uint_0; |
| |
| -- Loop through literals of enumeration type setting pos and rep values |
| -- except that if the Ekind is already set, then it means that the |
| -- literal was already constructed (case of a derived type declaration |
| -- and we should not disturb the Pos and Rep values. |
| |
| while Present (L) loop |
| if Ekind (L) /= E_Enumeration_Literal then |
| Set_Ekind (L, E_Enumeration_Literal); |
| Set_Enumeration_Pos (L, Ev); |
| Set_Enumeration_Rep (L, Ev); |
| Set_Is_Known_Valid (L, True); |
| end if; |
| |
| Set_Etype (L, T); |
| New_Overloaded_Entity (L); |
| Generate_Definition (L); |
| Set_Convention (L, Convention_Intrinsic); |
| |
| if Nkind (L) = N_Defining_Character_Literal then |
| Set_Is_Character_Type (T, True); |
| end if; |
| |
| Ev := Ev + 1; |
| Next (L); |
| end loop; |
| |
| -- Now create a node representing upper bound |
| |
| B_Node := New_Node (N_Identifier, Sloc (Def)); |
| Set_Chars (B_Node, Chars (Last (Literals (Def)))); |
| Set_Entity (B_Node, Last (Literals (Def))); |
| Set_Etype (B_Node, T); |
| Set_Is_Static_Expression (B_Node, True); |
| |
| Set_High_Bound (R_Node, B_Node); |
| Set_Scalar_Range (T, R_Node); |
| Set_RM_Size (T, UI_From_Int (Minimum_Size (T))); |
| Set_Enum_Esize (T); |
| |
| -- Set Discard_Names if configuration pragma set, or if there is |
| -- a parameterless pragma in the current declarative region |
| |
| if Global_Discard_Names |
| or else Discard_Names (Scope (T)) |
| then |
| Set_Discard_Names (T); |
| end if; |
| |
| -- Process end label if there is one |
| |
| if Present (Def) then |
| Process_End_Label (Def, 'e', T); |
| end if; |
| end Enumeration_Type_Declaration; |
| |
| --------------------------------- |
| -- Expand_To_Stored_Constraint -- |
| --------------------------------- |
| |
| function Expand_To_Stored_Constraint |
| (Typ : Entity_Id; |
| Constraint : Elist_Id) return Elist_Id |
| is |
| Explicitly_Discriminated_Type : Entity_Id; |
| Expansion : Elist_Id; |
| Discriminant : Entity_Id; |
| |
| function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id; |
| -- Find the nearest type that actually specifies discriminants |
| |
| --------------------------------- |
| -- Type_With_Explicit_Discrims -- |
| --------------------------------- |
| |
| function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is |
| Typ : constant E := Base_Type (Id); |
| |
| begin |
| if Ekind (Typ) in Incomplete_Or_Private_Kind then |
| if Present (Full_View (Typ)) then |
| return Type_With_Explicit_Discrims (Full_View (Typ)); |
| end if; |
| |
| else |
| if Has_Discriminants (Typ) then |
| return Typ; |
| end if; |
| end if; |
| |
| if Etype (Typ) = Typ then |
| return Empty; |
| elsif Has_Discriminants (Typ) then |
| return Typ; |
| else |
| return Type_With_Explicit_Discrims (Etype (Typ)); |
| end if; |
| |
| end Type_With_Explicit_Discrims; |
| |
| -- Start of processing for Expand_To_Stored_Constraint |
| |
| begin |
| if No (Constraint) |
| or else Is_Empty_Elmt_List (Constraint) |
| then |
| return No_Elist; |
| end if; |
| |
| Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ); |
| |
| if No (Explicitly_Discriminated_Type) then |
| return No_Elist; |
| end if; |
| |
| Expansion := New_Elmt_List; |
| |
| Discriminant := |
| First_Stored_Discriminant (Explicitly_Discriminated_Type); |
| while Present (Discriminant) loop |
| Append_Elmt ( |
| Get_Discriminant_Value ( |
| Discriminant, Explicitly_Discriminated_Type, Constraint), |
| Expansion); |
| Next_Stored_Discriminant (Discriminant); |
| end loop; |
| |
| return Expansion; |
| end Expand_To_Stored_Constraint; |
| |
| -------------------- |
| -- Find_Type_Name -- |
| -------------------- |
| |
| function Find_Type_Name (N : Node_Id) return Entity_Id is |
| Id : constant Entity_Id := Defining_Identifier (N); |
| Prev : Entity_Id; |
| New_Id : Entity_Id; |
| Prev_Par : Node_Id; |
| |
| begin |
| -- Find incomplete declaration, if one was given |
| |
| Prev := Current_Entity_In_Scope (Id); |
| |
| if Present (Prev) then |
| |
| -- Previous declaration exists. Error if not incomplete/private case |
| -- except if previous declaration is implicit, etc. Enter_Name will |
| -- emit error if appropriate. |
| |
| Prev_Par := Parent (Prev); |
| |
| if not Is_Incomplete_Or_Private_Type (Prev) then |
| Enter_Name (Id); |
| New_Id := Id; |
| |
| elsif Nkind (N) /= N_Full_Type_Declaration |
| and then Nkind (N) /= N_Task_Type_Declaration |
| and then Nkind (N) /= N_Protected_Type_Declaration |
| then |
| -- Completion must be a full type declarations (RM 7.3(4)) |
| |
| Error_Msg_Sloc := Sloc (Prev); |
| Error_Msg_NE ("invalid completion of }", Id, Prev); |
| |
| -- Set scope of Id to avoid cascaded errors. Entity is never |
| -- examined again, except when saving globals in generics. |
| |
| Set_Scope (Id, Current_Scope); |
| New_Id := Id; |
| |
| -- Case of full declaration of incomplete type |
| |
| elsif Ekind (Prev) = E_Incomplete_Type then |
| |
| -- Indicate that the incomplete declaration has a matching full |
| -- declaration. The defining occurrence of the incomplete |
| -- declaration remains the visible one, and the procedure |
| -- Get_Full_View dereferences it whenever the type is used. |
| |
| if Present (Full_View (Prev)) then |
| Error_Msg_NE ("invalid redeclaration of }", Id, Prev); |
| end if; |
| |
| Set_Full_View (Prev, Id); |
| Append_Entity (Id, Current_Scope); |
| Set_Is_Public (Id, Is_Public (Prev)); |
| Set_Is_Internal (Id); |
| New_Id := Prev; |
| |
| -- Case of full declaration of private type |
| |
| else |
| if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then |
| if Etype (Prev) /= Prev then |
| |
| -- Prev is a private subtype or a derived type, and needs |
| -- no completion. |
| |
| Error_Msg_NE ("invalid redeclaration of }", Id, Prev); |
| New_Id := Id; |
| |
| elsif Ekind (Prev) = E_Private_Type |
| and then |
| (Nkind (N) = N_Task_Type_Declaration |
| or else Nkind (N) = N_Protected_Type_Declaration) |
| then |
| Error_Msg_N |
| ("completion of nonlimited type cannot be limited", N); |
| |
| elsif Ekind (Prev) = E_Record_Type_With_Private |
| and then |
| (Nkind (N) = N_Task_Type_Declaration |
| or else Nkind (N) = N_Protected_Type_Declaration) |
| then |
| if not Is_Limited_Record (Prev) then |
| Error_Msg_N |
| ("completion of nonlimited type cannot be limited", N); |
| |
| elsif No (Interface_List (N)) then |
| Error_Msg_N |
| ("completion of tagged private type must be tagged", |
| N); |
| end if; |
| end if; |
| |
| -- Ada 2005 (AI-251): Private extension declaration of a |
| -- task type. This case arises with tasks implementing interfaces |
| |
| elsif Nkind (N) = N_Task_Type_Declaration |
| or else Nkind (N) = N_Protected_Type_Declaration |
| then |
| null; |
| |
| elsif Nkind (N) /= N_Full_Type_Declaration |
| or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition |
| then |
| Error_Msg_N |
| ("full view of private extension must be an extension", N); |
| |
| elsif not (Abstract_Present (Parent (Prev))) |
| and then Abstract_Present (Type_Definition (N)) |
| then |
| Error_Msg_N |
| ("full view of non-abstract extension cannot be abstract", N); |
| end if; |
| |
| if not In_Private_Part (Current_Scope) then |
| Error_Msg_N |
| ("declaration of full view must appear in private part", N); |
| end if; |
| |
| Copy_And_Swap (Prev, Id); |
| Set_Has_Private_Declaration (Prev); |
| Set_Has_Private_Declaration (Id); |
| |
| -- If no error, propagate freeze_node from private to full view. |
| -- It may have been generated for an early operational item. |
| |
| if Present (Freeze_Node (Id)) |
| and then Serious_Errors_Detected = 0 |
| and then No (Full_View (Id)) |
| then |
| Set_Freeze_Node (Prev, Freeze_Node (Id)); |
| Set_Freeze_Node (Id, Empty); |
| Set_First_Rep_Item (Prev, First_Rep_Item (Id)); |
| end if; |
| |
| Set_Full_View (Id, Prev); |
| New_Id := Prev; |
| end if; |
| |
| -- Verify that full declaration conforms to incomplete one |
| |
| if Is_Incomplete_Or_Private_Type (Prev) |
| and then Present (Discriminant_Specifications (Prev_Par)) |
| then |
| if Present (Discriminant_Specifications (N)) then |
| if Ekind (Prev) = E_Incomplete_Type then |
| Check_Discriminant_Conformance (N, Prev, Prev); |
| else |
| Check_Discriminant_Conformance (N, Prev, Id); |
| end if; |
| |
| else |
| Error_Msg_N |
| ("missing discriminants in full type declaration", N); |
| |
| -- To avoid cascaded errors on subsequent use, share the |
| -- discriminants of the partial view. |
| |
| Set_Discriminant_Specifications (N, |
| Discriminant_Specifications (Prev_Par)); |
| end if; |
| end if; |
| |
| -- A prior untagged private type can have an associated class-wide |
| -- type due to use of the class attribute, and in this case also the |
| -- full type is required to be tagged. |
| |
| if Is_Type (Prev) |
| and then (Is_Tagged_Type (Prev) |
| or else Present (Class_Wide_Type (Prev))) |
| and then (Nkind (N) /= N_Task_Type_Declaration |
| and then Nkind (N) /= N_Protected_Type_Declaration) |
| then |
| -- The full declaration is either a tagged record or an |
| -- extension otherwise this is an error |
| |
| if Nkind (Type_Definition (N)) = N_Record_Definition then |
| if not Tagged_Present (Type_Definition (N)) then |
| Error_Msg_NE |
| ("full declaration of } must be tagged", Prev, Id); |
| Set_Is_Tagged_Type (Id); |
| Set_Primitive_Operations (Id, New_Elmt_List); |
| end if; |
| |
| elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then |
| if No (Record_Extension_Part (Type_Definition (N))) then |
| Error_Msg_NE ( |
| "full declaration of } must be a record extension", |
| Prev, Id); |
| Set_Is_Tagged_Type (Id); |
| Set_Primitive_Operations (Id, New_Elmt_List); |
| end if; |
| |
| else |
| Error_Msg_NE |
| ("full declaration of } must be a tagged type", Prev, Id); |
| |
| end if; |
| end if; |
| |
| return New_Id; |
| |
| else |
| -- New type declaration |
| |
| Enter_Name (Id); |
| return Id; |
| end if; |
| end Find_Type_Name; |
| |
| ------------------------- |
| -- Find_Type_Of_Object -- |
| ------------------------- |
| |
| function Find_Type_Of_Object |
| (Obj_Def : Node_Id; |
| Related_Nod : Node_Id) return Entity_Id |
| is |
| Def_Kind : constant Node_Kind := Nkind (Obj_Def); |
| P : Node_Id := Parent (Obj_Def); |
| T : Entity_Id; |
| Nam : Name_Id; |
| |
| begin |
| -- If the parent is a component_definition node we climb to the |
| -- component_declaration node |
| |
| if Nkind (P) = N_Component_Definition then |
| P := Parent (P); |
| end if; |
| |
| -- Case of an anonymous array subtype |
| |
| if Def_Kind = N_Constrained_Array_Definition |
| or else Def_Kind = N_Unconstrained_Array_Definition |
| then |
| T := Empty; |
| Array_Type_Declaration (T, Obj_Def); |
| |
| -- Create an explicit subtype whenever possible |
| |
| elsif Nkind (P) /= N_Component_Declaration |
| and then Def_Kind = N_Subtype_Indication |
| then |
| -- Base name of subtype on object name, which will be unique in |
| -- the current scope. |
| |
| -- If this is a duplicate declaration, return base type, to avoid |
| -- generating duplicate anonymous types. |
| |
| if Error_Posted (P) then |
| Analyze (Subtype_Mark (Obj_Def)); |
| return Entity (Subtype_Mark (Obj_Def)); |
| end if; |
| |
| Nam := |
| New_External_Name |
| (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T'); |
| |
| T := Make_Defining_Identifier (Sloc (P), Nam); |
| |
| Insert_Action (Obj_Def, |
| Make_Subtype_Declaration (Sloc (P), |
| Defining_Identifier => T, |
| Subtype_Indication => Relocate_Node (Obj_Def))); |
| |
| -- This subtype may need freezing, and this will not be done |
| -- automatically if the object declaration is not in declarative |
| -- part. Since this is an object declaration, the type cannot always |
| -- be frozen here. Deferred constants do not freeze their type |
| -- (which often enough will be private). |
| |
| if Nkind (P) = N_Object_Declaration |
| and then Constant_Present (P) |
| and then No (Expression (P)) |
| then |
| null; |
| else |
| Insert_Actions (Obj_Def, Freeze_Entity (T, Sloc (P))); |
| end if; |
| |
| -- Ada 2005 AI-406: the object definition in an object declaration |
| -- can be an access definition. |
| |
| elsif Def_Kind = N_Access_Definition then |
| T := Access_Definition (Related_Nod, Obj_Def); |
| Set_Is_Local_Anonymous_Access (T); |
| |
| -- comment here, what cases ??? |
| |
| else |
| T := Process_Subtype (Obj_Def, Related_Nod); |
| end if; |
| |
| return T; |
| end Find_Type_Of_Object; |
| |
| -------------------------------- |
| -- Find_Type_Of_Subtype_Indic -- |
| -------------------------------- |
| |
| function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is |
| Typ : Entity_Id; |
| |
| begin |
| -- Case of subtype mark with a constraint |
| |
| if Nkind (S) = N_Subtype_Indication then |
| Find_Type (Subtype_Mark (S)); |
| Typ := Entity (Subtype_Mark (S)); |
| |
| if not |
| Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S))) |
| then |
| Error_Msg_N |
| ("incorrect constraint for this kind of type", Constraint (S)); |
| Rewrite (S, New_Copy_Tree (Subtype_Mark (S))); |
| end if; |
| |
| -- Otherwise we have a subtype mark without a constraint |
| |
| elsif Error_Posted (S) then |
| Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S))); |
| return Any_Type; |
| |
| else |
| Find_Type (S); |
| Typ := Entity (S); |
| end if; |
| |
| if Typ = Standard_Wide_Character |
| or else Typ = Standard_Wide_Wide_Character |
| or else Typ = Standard_Wide_String |
| or else Typ = Standard_Wide_Wide_String |
| then |
| Check_Restriction (No_Wide_Characters, S); |
| end if; |
| |
| return Typ; |
| end Find_Type_Of_Subtype_Indic; |
| |
| ------------------------------------- |
| -- Floating_Point_Type_Declaration -- |
| ------------------------------------- |
| |
| procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is |
| Digs : constant Node_Id := Digits_Expression (Def); |
| Digs_Val : Uint; |
| Base_Typ : Entity_Id; |
| Implicit_Base : Entity_Id; |
| Bound : Node_Id; |
| |
| function Can_Derive_From (E : Entity_Id) return Boolean; |
| -- Find if given digits value allows derivation from specified type |
| |
| --------------------- |
| -- Can_Derive_From -- |
| --------------------- |
| |
| function Can_Derive_From (E : Entity_Id) return Boolean is |
| Spec : constant Entity_Id := Real_Range_Specification (Def); |
| |
| begin |
| if Digs_Val > Digits_Value (E) then |
| return False; |
| end if; |
| |
| if Present (Spec) then |
| if Expr_Value_R (Type_Low_Bound (E)) > |
| Expr_Value_R (Low_Bound (Spec)) |
| then |
| return False; |
| end if; |
| |
| if Expr_Value_R (Type_High_Bound (E)) < |
| Expr_Value_R (High_Bound (Spec)) |
| then |
| return False; |
| end if; |
| end if; |
| |
| return True; |
| end Can_Derive_From; |
| |
| -- Start of processing for Floating_Point_Type_Declaration |
| |
| begin |
| Check_Restriction (No_Floating_Point, Def); |
| |
| -- Create an implicit base type |
| |
| Implicit_Base := |
| Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B'); |
| |
| -- Analyze and verify digits value |
| |
| Analyze_And_Resolve (Digs, Any_Integer); |
| Check_Digits_Expression (Digs); |
| Digs_Val := Expr_Value (Digs); |
| |
| -- Process possible range spec and find correct type to derive from |
| |
| Process_Real_Range_Specification (Def); |
| |
| if Can_Derive_From (Standard_Short_Float) then |
| Base_Typ := Standard_Short_Float; |
| elsif Can_Derive_From (Standard_Float) then |
| Base_Typ := Standard_Float; |
| elsif Can_Derive_From (Standard_Long_Float) then |
| Base_Typ := Standard_Long_Float; |
| elsif Can_Derive_From (Standard_Long_Long_Float) then |
| Base_Typ := Standard_Long_Long_Float; |
| |
| -- If we can't derive from any existing type, use long_long_float |
| -- and give appropriate message explaining the problem. |
| |
| else |
| Base_Typ := Standard_Long_Long_Float; |
| |
| if Digs_Val >= Digits_Value (Standard_Long_Long_Float) then |
| Error_Msg_Uint_1 := Digits_Value (Standard_Long_Long_Float); |
| Error_Msg_N ("digits value out of range, maximum is ^", Digs); |
| |
| else |
| Error_Msg_N |
| ("range too large for any predefined type", |
| Real_Range_Specification (Def)); |
| end if; |
| end if; |
| |
| -- If there are bounds given in the declaration use them as the bounds |
| -- of the type, otherwise use the bounds of the predefined base type |
| -- that was chosen based on the Digits value. |
| |
| if Present (Real_Range_Specification (Def)) then |
| Set_Scalar_Range (T, Real_Range_Specification (Def)); |
| Set_Is_Constrained (T); |
| |
| -- The bounds of this range must be converted to machine numbers |
| -- in accordance with RM 4.9(38). |
| |
| Bound := Type_Low_Bound (T); |
| |
| if Nkind (Bound) = N_Real_Literal then |
| Set_Realval |
| (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound)); |
| Set_Is_Machine_Number (Bound); |
| end if; |
| |
| Bound := Type_High_Bound (T); |
| |
| if Nkind (Bound) = N_Real_Literal then |
| Set_Realval |
| (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound)); |
| Set_Is_Machine_Number (Bound); |
| end if; |
| |
| else |
| Set_Scalar_Range (T, Scalar_Range (Base_Typ)); |
| end if; |
| |
| -- Complete definition of implicit base and declared first subtype |
| |
| Set_Etype (Implicit_Base, Base_Typ); |
| |
| Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ)); |
| Set_Size_Info (Implicit_Base, (Base_Typ)); |
| Set_RM_Size (Implicit_Base, RM_Size (Base_Typ)); |
| Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ)); |
| Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ)); |
| Set_Vax_Float (Implicit_Base, Vax_Float (Base_Typ)); |
| |
| Set_Ekind (T, E_Floating_Point_Subtype); |
| Set_Etype (T, Implicit_Base); |
| |
| Set_Size_Info (T, (Implicit_Base)); |
| Set_RM_Size (T, RM_Size (Implicit_Base)); |
| Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base)); |
| Set_Digits_Value (T, Digs_Val); |
| end Floating_Point_Type_Declaration; |
| |
| ---------------------------- |
| -- Get_Discriminant_Value -- |
| ---------------------------- |
| |
| -- This is the situation: |
| |
| -- There is a non-derived type |
| |
| -- type T0 (Dx, Dy, Dz...) |
| |
| -- There are zero or more levels of derivation, with each derivation |
| -- either purely inheriting the discriminants, or defining its own. |
| |
| -- type Ti is new Ti-1 |
| -- or |
| -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y) |
| -- or |
| -- subtype Ti is ... |
| |
| -- The subtype issue is avoided by the use of Original_Record_Component, |
| -- and the fact that derived subtypes also derive the constraints. |
| |
| -- This chain leads back from |
| |
| -- Typ_For_Constraint |
| |
| -- Typ_For_Constraint has discriminants, and the value for each |
| -- discriminant is given by its corresponding Elmt of Constraints. |
| |
| -- Discriminant is some discriminant in this hierarchy |
| |
| -- We need to return its value |
| |
| -- We do this by recursively searching each level, and looking for |
| -- Discriminant. Once we get to the bottom, we start backing up |
| -- returning the value for it which may in turn be a discriminant |
| -- further up, so on the backup we continue the substitution. |
| |
| function Get_Discriminant_Value |
| (Discriminant : Entity_Id; |
| Typ_For_Constraint : Entity_Id; |
| Constraint : Elist_Id) return Node_Id |
| is |
| function Search_Derivation_Levels |
| (Ti : Entity_Id; |
| Discrim_Values : Elist_Id; |
| Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id; |
| -- This is the routine that performs the recursive search of levels |
| -- as described above. |
| |
| ------------------------------ |
| -- Search_Derivation_Levels -- |
| ------------------------------ |
| |
| function Search_Derivation_Levels |
| (Ti : Entity_Id; |
| Discrim_Values : Elist_Id; |
| Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id |
| is |
| Assoc : Elmt_Id; |
| Disc : Entity_Id; |
| Result : Node_Or_Entity_Id; |
| Result_Entity : Node_Id; |
| |
| begin |
| -- If inappropriate type, return Error, this happens only in |
| -- cascaded error situations, and we want to avoid a blow up. |
| |
| if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then |
| return Error; |
| end if; |
| |
| -- Look deeper if possible. Use Stored_Constraints only for |
| -- untagged types. For tagged types use the given constraint. |
| -- This asymmetry needs explanation??? |
| |
| if not Stored_Discrim_Values |
| and then Present (Stored_Constraint (Ti)) |
| and then not Is_Tagged_Type (Ti) |
| then |
| Result := |
| Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True); |
| else |
| declare |
| Td : constant Entity_Id := Etype (Ti); |
| |
| begin |
| if Td = Ti then |
| Result := Discriminant; |
| |
| else |
| if Present (Stored_Constraint (Ti)) then |
| Result := |
| Search_Derivation_Levels |
| (Td, Stored_Constraint (Ti), True); |
| else |
| Result := |
| Search_Derivation_Levels |
| (Td, Discrim_Values, Stored_Discrim_Values); |
| end if; |
| end if; |
| end; |
| end if; |
| |
| -- Extra underlying places to search, if not found above. For |
| -- concurrent types, the relevant discriminant appears in the |
| -- corresponding record. For a type derived from a private type |
| -- without discriminant, the full view inherits the discriminants |
| -- of the full view of the parent. |
| |
| if Result = Discriminant then |
| if Is_Concurrent_Type (Ti) |
| and then Present (Corresponding_Record_Type (Ti)) |
| then |
| Result := |
| Search_Derivation_Levels ( |
| Corresponding_Record_Type (Ti), |
| Discrim_Values, |
| Stored_Discrim_Values); |
| |
| elsif Is_Private_Type (Ti) |
| and then not Has_Discriminants (Ti) |
| and then Present (Full_View (Ti)) |
| and then Etype (Full_View (Ti)) /= Ti |
| then |
| Result := |
| Search_Derivation_Levels ( |
| Full_View (Ti), |
| Discrim_Values, |
| Stored_Discrim_Values); |
| end if; |
| end if; |
| |
| -- If Result is not a (reference to a) discriminant, return it, |
| -- otherwise set Result_Entity to the discriminant. |
| |
| if Nkind (Result) = N_Defining_Identifier then |
| pragma Assert (Result = Discriminant); |
| Result_Entity := Result; |
| |
| else |
| if not Denotes_Discriminant (Result) then |
| return Result; |
| end if; |
| |
| Result_Entity := Entity (Result); |
| end if; |
| |
| -- See if this level of derivation actually has discriminants |
| -- because tagged derivations can add them, hence the lower |
| -- levels need not have any. |
| |
| if not Has_Discriminants (Ti) then |
| return Result; |
| end if; |
| |
| -- Scan Ti's discriminants for Result_Entity, |
| -- and return its corresponding value, if any. |
| |
| Result_Entity := Original_Record_Component (Result_Entity); |
| |
| Assoc := First_Elmt (Discrim_Values); |
| |
| if Stored_Discrim_Values then |
| Disc := First_Stored_Discriminant (Ti); |
| else |
| Disc := First_Discriminant (Ti); |
| end if; |
| |
| while Present (Disc) loop |
| pragma Assert (Present (Assoc)); |
| |
| if Original_Record_Component (Disc) = Result_Entity then |
| return Node (Assoc); |
| end if; |
| |
| Next_Elmt (Assoc); |
| |
| if Stored_Discrim_Values then |
| Next_Stored_Discriminant (Disc); |
| else |
| Next_Discriminant (Disc); |
| end if; |
| end loop; |
| |
| -- Could not find it |
| -- |
| return Result; |
| end Search_Derivation_Levels; |
| |
| Result : Node_Or_Entity_Id; |
| |
| -- Start of processing for Get_Discriminant_Value |
| |
| begin |
| -- ??? This routine is a gigantic mess and will be deleted. For the |
| -- time being just test for the trivial case before calling recurse. |
| |
| if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then |
| declare |
| D : Entity_Id; |
| E : Elmt_Id; |
| |
| begin |
| D := First_Discriminant (Typ_For_Constraint); |
| E := First_Elmt (Constraint); |
| while Present (D) loop |
| if Chars (D) = Chars (Discriminant) then |
| return Node (E); |
| end if; |
| |
| Next_Discriminant (D); |
| Next_Elmt (E); |
| end loop; |
| end; |
| end if; |
| |
| Result := Search_Derivation_Levels |
| (Typ_For_Constraint, Constraint, False); |
| |
| -- ??? hack to disappear when this routine is gone |
| |
| if Nkind (Result) = N_Defining_Identifier then |
| declare |
| D : Entity_Id; |
| E : Elmt_Id; |
| |
| begin |
| D := First_Discriminant (Typ_For_Constraint); |
| E := First_Elmt (Constraint); |
| while Present (D) loop |
| if Corresponding_Discriminant (D) = Discriminant then |
| return Node (E); |
| end if; |
| |
| Next_Discriminant (D); |
| Next_Elmt (E); |
| end loop; |
| end; |
| end if; |
| |
| pragma Assert (Nkind (Result) /= N_Defining_Identifier); |
| return Result; |
| end Get_Discriminant_Value; |
| |
| -------------------------- |
| -- Has_Range_Constraint -- |
| -------------------------- |
| |
| function Has_Range_Constraint (N : Node_Id) return Boolean is |
| C : constant Node_Id := Constraint (N); |
| |
| begin |
| if Nkind (C) = N_Range_Constraint then |
| return True; |
| |
| elsif Nkind (C) = N_Digits_Constraint then |
| return |
| Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N))) |
| or else |
| Present (Range_Constraint (C)); |
| |
| elsif Nkind (C) = N_Delta_Constraint then |
| return Present (Range_Constraint (C)); |
| |
| else |
| return False; |
| end if; |
| end Has_Range_Constraint; |
| |
| ------------------------ |
| -- Inherit_Components -- |
| ------------------------ |
| |
| function Inherit_Components |
| (N : Node_Id; |
| Parent_Base : Entity_Id; |
| Derived_Base : Entity_Id; |
| Is_Tagged : Boolean; |
| Inherit_Discr : Boolean; |
| Discs : Elist_Id) return Elist_Id |
| is |
| Assoc_List : constant Elist_Id := New_Elmt_List; |
| |
| procedure Inherit_Component |
| (Old_C : Entity_Id; |
| Plain_Discrim : Boolean := False; |
| Stored_Discrim : Boolean := False); |
| -- Inherits component Old_C from Parent_Base to the Derived_Base. If |
| -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is |
| -- True, Old_C is a stored discriminant. If they are both false then |
| -- Old_C is a regular component. |
| |
| ----------------------- |
| -- Inherit_Component -- |
| ----------------------- |
| |
| procedure Inherit_Component |
| (Old_C : Entity_Id; |
| Plain_Discrim : Boolean := False; |
| Stored_Discrim : Boolean := False) |
| is |
| New_C : constant Entity_Id := New_Copy (Old_C); |
| |
| Discrim : Entity_Id; |
| Corr_Discrim : Entity_Id; |
| |
| begin |
| pragma Assert (not Is_Tagged or else not Stored_Discrim); |
| |
| Set_Parent (New_C, Parent (Old_C)); |
| |
| -- Regular discriminants and components must be inserted |
| -- in the scope of the Derived_Base. Do it here. |
| |
| if not Stored_Discrim then |
| Enter_Name (New_C); |
| end if; |
| |
| -- For tagged types the Original_Record_Component must point to |
| -- whatever this field was pointing to in the parent type. This has |
| -- already been achieved by the call to New_Copy above. |
| |
| if not Is_Tagged then |
| Set_Original_Record_Component (New_C, New_C); |
| end if; |
| |
| -- If we have inherited a component then see if its Etype contains |
| -- references to Parent_Base discriminants. In this case, replace |
| -- these references with the constraints given in Discs. We do not |
| -- do this for the partial view of private types because this is |
| -- not needed (only the components of the full view will be used |
| -- for code generation) and cause problem. We also avoid this |
| -- transformation in some error situations. |
| |
| if Ekind (New_C) = E_Component then |
| if (Is_Private_Type (Derived_Base) |
| and then not Is_Generic_Type (Derived_Base)) |
| or else (Is_Empty_Elmt_List (Discs) |
| and then not Expander_Active) |
| then |
| Set_Etype (New_C, Etype (Old_C)); |
| else |
| Set_Etype |
| (New_C, |
| Constrain_Component_Type |
| (Old_C, Derived_Base, N, Parent_Base, Discs)); |
| end if; |
| end if; |
| |
| -- In derived tagged types it is illegal to reference a non |
| -- discriminant component in the parent type. To catch this, mark |
| -- these components with an Ekind of E_Void. This will be reset in |
| -- Record_Type_Definition after processing the record extension of |
| -- the derived type. |
| |
| if Is_Tagged and then Ekind (New_C) = E_Component then |
| Set_Ekind (New_C, E_Void); |
| end if; |
| |
| if Plain_Discrim then |
| Set_Corresponding_Discriminant (New_C, Old_C); |
| Build_Discriminal (New_C); |
| |
| -- If we are explicitly inheriting a stored discriminant it will be |
| -- completely hidden. |
| |
| elsif Stored_Discrim then |
| Set_Corresponding_Discriminant (New_C, Empty); |
| Set_Discriminal (New_C, Empty); |
| Set_Is_Completely_Hidden (New_C); |
| |
| -- Set the Original_Record_Component of each discriminant in the |
| -- derived base to point to the corresponding stored that we just |
| -- created. |
| |
| Discrim := First_Discriminant (Derived_Base); |
| while Present (Discrim) loop |
| Corr_Discrim := Corresponding_Discriminant (Discrim); |
| |
| -- Corr_Discrim could be missing in an error situation |
| |
| if Present (Corr_Discrim) |
| and then Original_Record_Component (Corr_Discrim) = Old_C |
| then |
| Set_Original_Record_Component (Discrim, New_C); |
| end if; |
| |
| Next_Discriminant (Discrim); |
| end loop; |
| |
| Append_Entity (New_C, Derived_Base); |
| end if; |
| |
| if not Is_Tagged then |
| Append_Elmt (Old_C, Assoc_List); |
| Append_Elmt (New_C, Assoc_List); |
| end if; |
| end Inherit_Component; |
| |
| -- Variables local to Inherit_Component |
| |
| Loc : constant Source_Ptr := Sloc (N); |
| |
| Parent_Discrim : Entity_Id; |
| Stored_Discrim : Entity_Id; |
| D : Entity_Id; |
| Component : Entity_Id; |
| |
| -- Start of processing for Inherit_Components |
| |
| begin |
| if not Is_Tagged then |
| Append_Elmt (Parent_Base, Assoc_List); |
| Append_Elmt (Derived_Base, Assoc_List); |
| end if; |
| |
| -- Inherit parent discriminants if needed |
| |
| if Inherit_Discr then |
| Parent_Discrim := First_Discriminant (Parent_Base); |
| while Present (Parent_Discrim) loop |
| Inherit_Component (Parent_Discrim, Plain_Discrim => True); |
| Next_Discriminant (Parent_Discrim); |
| end loop; |
| end if; |
| |
| -- Create explicit stored discrims for untagged types when necessary |
| |
| if not Has_Unknown_Discriminants (Derived_Base) |
| and then Has_Discriminants (Parent_Base) |
| and then not Is_Tagged |
| and then |
| (not Inherit_Discr |
| or else First_Discriminant (Parent_Base) /= |
| First_Stored_Discriminant (Parent_Base)) |
| then |
| Stored_Discrim := First_Stored_Discriminant (Parent_Base); |
| while Present (Stored_Discrim) loop |
| Inherit_Component (Stored_Discrim, Stored_Discrim => True); |
| Next_Stored_Discriminant (Stored_Discrim); |
| end loop; |
| end if; |
| |
| -- See if we can apply the second transformation for derived types, as |
| -- explained in point 6. in the comments above Build_Derived_Record_Type |
| -- This is achieved by appending Derived_Base discriminants into Discs, |
| -- which has the side effect of returning a non empty Discs list to the |
| -- caller of Inherit_Components, which is what we want. This must be |
| -- done for private derived types if there are explicit stored |
| -- discriminants, to ensure that we can retrieve the values of the |
| -- constraints provided in the ancestors. |
| |
| if Inherit_Discr |
| and then Is_Empty_Elmt_List (Discs) |
| and then Present (First_Discriminant (Derived_Base)) |
| and then |
| (not Is_Private_Type (Derived_Base) |
| or else Is_Completely_Hidden |
| (First_Stored_Discriminant (Derived_Base)) |
| or else Is_Generic_Type (Derived_Base)) |
| then |
| D := First_Discriminant (Derived_Base); |
| while Present (D) loop |
| Append_Elmt (New_Reference_To (D, Loc), Discs); |
| Next_Discriminant (D); |
| end loop; |
| end if; |
| |
| -- Finally, inherit non-discriminant components unless they are not |
| -- visible because defined or inherited from the full view of the |
| -- parent. Don't inherit the _parent field of the parent type. |
| |
| Component := First_Entity (Parent_Base); |
| while Present (Component) loop |
| |
| -- Ada 2005 (AI-251): Do not inherit tags corresponding with the |
| -- interfaces of the parent |
| |
| if Ekind (Component) = E_Component |
| and then Is_Tag (Component) |
| and then RTE_Available (RE_Interface_Tag) |
| and then Etype (Component) = RTE (RE_Interface_Tag) |
| then |
| null; |
| |
| elsif Ekind (Component) /= E_Component |
| or else Chars (Component) = Name_uParent |
| then |
| null; |
| |
| -- If the derived type is within the parent type's declarative |
| -- region, then the components can still be inherited even though |
| -- they aren't visible at this point. This can occur for cases |
| -- such as within public child units where the components must |
| -- become visible upon entering the child unit's private part. |
| |
| elsif not Is_Visible_Component (Component) |
| and then not In_Open_Scopes (Scope (Parent_Base)) |
| then |
| null; |
| |
| elsif Ekind (Derived_Base) = E_Private_Type |
| or else Ekind (Derived_Base) = E_Limited_Private_Type |
| then |
| null; |
| |
| else |
| Inherit_Component (Component); |
| end if; |
| |
| Next_Entity (Component); |
| end loop; |
| |
| -- For tagged derived types, inherited discriminants cannot be used in |
| -- component declarations of the record extension part. To achieve this |
| -- we mark the inherited discriminants as not visible. |
| |
| if Is_Tagged and then Inherit_Discr then |
| D := First_Discriminant (Derived_Base); |
| while Present (D) loop |
| Set_Is_Immediately_Visible (D, False); |
| Next_Discriminant (D); |
| end loop; |
| end if; |
| |
| return Assoc_List; |
| end Inherit_Components; |
| |
| ----------------------- |
| -- Is_Null_Extension -- |
| ----------------------- |
| |
| function Is_Null_Extension (T : Entity_Id) return Boolean is |
| Full_Type_Decl : constant Node_Id := Parent (T); |
| Full_Type_Defn : constant Node_Id := Type_Definition (Full_Type_Decl); |
| Comp_List : Node_Id; |
| First_Comp : Node_Id; |
| |
| begin |
| if not Is_Tagged_Type (T) |
| or else Nkind (Full_Type_Defn) /= N_Derived_Type_Definition |
| then |
| return False; |
| end if; |
| |
| Comp_List := Component_List (Record_Extension_Part (Full_Type_Defn)); |
| |
| if Present (Discriminant_Specifications (Full_Type_Decl)) then |
| return False; |
| |
| elsif Present (Comp_List) |
| and then Is_Non_Empty_List (Component_Items (Comp_List)) |
| then |
| First_Comp := First (Component_Items (Comp_List)); |
| |
| return Chars (Defining_Identifier (First_Comp)) = Name_uParent |
| and then No (Next (First_Comp)); |
| |
| else |
| return True; |
| end if; |
| end Is_Null_Extension; |
| |
| ------------------------------ |
| -- Is_Valid_Constraint_Kind -- |
| ------------------------------ |
| |
| function Is_Valid_Constraint_Kind |
| (T_Kind : Type_Kind; |
| Constraint_Kind : Node_Kind) return Boolean |
| is |
| begin |
| case T_Kind is |
| when Enumeration_Kind | |
| Integer_Kind => |
| return Constraint_Kind = N_Range_Constraint; |
| |
| when Decimal_Fixed_Point_Kind => |
| return |
| Constraint_Kind = N_Digits_Constraint |
| or else |
| Constraint_Kind = N_Range_Constraint; |
| |
| when Ordinary_Fixed_Point_Kind => |
| return |
| Constraint_Kind = N_Delta_Constraint |
| or else |
| Constraint_Kind = N_Range_Constraint; |
| |
| when Float_Kind => |
| return |
| Constraint_Kind = N_Digits_Constraint |
| or else |
| Constraint_Kind = N_Range_Constraint; |
| |
| when Access_Kind | |
| Array_Kind | |
| E_Record_Type | |
| E_Record_Subtype | |
| Class_Wide_Kind | |
| E_Incomplete_Type | |
| Private_Kind | |
| Concurrent_Kind => |
| return Constraint_Kind = N_Index_Or_Discriminant_Constraint; |
| |
| when others => |
| return True; -- Error will be detected later |
| end case; |
| end Is_Valid_Constraint_Kind; |
| |
| -------------------------- |
| -- Is_Visible_Component -- |
| -------------------------- |
| |
| function Is_Visible_Component (C : Entity_Id) return Boolean is |
| Original_Comp : Entity_Id := Empty; |
| Original_Scope : Entity_Id; |
| Type_Scope : Entity_Id; |
| |
| function Is_Local_Type (Typ : Entity_Id) return Boolean; |
| -- Check whether parent type of inherited component is declared locally, |
| -- possibly within a nested package or instance. The current scope is |
| -- the derived record itself. |
| |
| ------------------- |
| -- Is_Local_Type -- |
| ------------------- |
| |
| function Is_Local_Type (Typ : Entity_Id) return Boolean is |
| Scop : Entity_Id; |
| |
| begin |
| Scop := Scope (Typ); |
| while Present (Scop) |
| and then Scop /= Standard_Standard |
| loop |
| if Scop = Scope (Current_Scope) then |
| return True; |
| end if; |
| |
| Scop := Scope (Scop); |
| end loop; |
| |
| return False; |
| end Is_Local_Type; |
| |
| -- Start of processing for Is_Visible_Component |
| |
| begin |
| if Ekind (C) = E_Component |
| or else Ekind (C) = E_Discriminant |
| then |
| Original_Comp := Original_Record_Component (C); |
| end if; |
| |
| if No (Original_Comp) then |
| |
| -- Premature usage, or previous error |
| |
| return False; |
| |
| else |
| Original_Scope := Scope (Original_Comp); |
| Type_Scope := Scope (Base_Type (Scope (C))); |
| end if; |
| |
| -- This test only concerns tagged types |
| |
| if not Is_Tagged_Type (Original_Scope) then |
| return True; |
| |
| -- If it is _Parent or _Tag, there is no visibility issue |
| |
| elsif not Comes_From_Source (Original_Comp) then |
| return True; |
| |
| -- If we are in the body of an instantiation, the component is visible |
| -- even when the parent type (possibly defined in an enclosing unit or |
| -- in a parent unit) might not. |
| |
| elsif In_Instance_Body then |
| return True; |
| |
| -- Discriminants are always visible |
| |
| elsif Ekind (Original_Comp) = E_Discriminant |
| and then not Has_Unknown_Discriminants (Original_Scope) |
| then |
| return True; |
| |
| -- If the component has been declared in an ancestor which is currently |
| -- a private type, then it is not visible. The same applies if the |
| -- component's containing type is not in an open scope and the original |
| -- component's enclosing type is a visible full type of a private type |
| -- (which can occur in cases where an attempt is being made to reference |
| -- a component in a sibling package that is inherited from a visible |
| -- component of a type in an ancestor package; the component in the |
| -- sibling package should not be visible even though the component it |
| -- inherited from is visible). This does not apply however in the case |
| -- where the scope of the type is a private child unit, or when the |
| -- parent comes from a local package in which the ancestor is currently |
| -- visible. The latter suppression of visibility is needed for cases |
| -- that are tested in B730006. |
| |
| elsif Is_Private_Type (Original_Scope) |
| or else |
| (not Is_Private_Descendant (Type_Scope) |
| and then not In_Open_Scopes (Type_Scope) |
| and then Has_Private_Declaration (Original_Scope)) |
| then |
| -- If the type derives from an entity in a formal package, there |
| -- are no additional visible components. |
| |
| if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) = |
| N_Formal_Package_Declaration |
| then |
| return False; |
| |
| -- if we are not in the private part of the current package, there |
| -- are no additional visible components. |
| |
| elsif Ekind (Scope (Current_Scope)) = E_Package |
| and then not In_Private_Part (Scope (Current_Scope)) |
| then |
| return False; |
| else |
| return |
| Is_Child_Unit (Cunit_Entity (Current_Sem_Unit)) |
| and then Is_Local_Type (Type_Scope); |
| end if; |
| |
| -- There is another weird way in which a component may be invisible |
| -- when the private and the full view are not derived from the same |
| -- ancestor. Here is an example : |
| |
| -- type A1 is tagged record F1 : integer; end record; |
| -- type A2 is new A1 with record F2 : integer; end record; |
| -- type T is new A1 with private; |
| -- private |
| -- type T is new A2 with null record; |
| |
| -- In this case, the full view of T inherits F1 and F2 but the private |
| -- view inherits only F1 |
| |
| else |
| declare |
| Ancestor : Entity_Id := Scope (C); |
| |
| begin |
| loop |
| if Ancestor = Original_Scope then |
| return True; |
| elsif Ancestor = Etype (Ancestor) then |
| return False; |
| end if; |
| |
| Ancestor := Etype (Ancestor); |
| end loop; |
| |
| -- LLVM local deleted unreachable line |
| end; |
| end if; |
| end Is_Visible_Component; |
| |
| -------------------------- |
| -- Make_Class_Wide_Type -- |
| -------------------------- |
| |
| procedure Make_Class_Wide_Type (T : Entity_Id) is |
| CW_Type : Entity_Id; |
| CW_Name : Name_Id; |
| Next_E : Entity_Id; |
| |
| begin |
| -- The class wide type can have been defined by the partial view in |
| -- which case everything is already done |
| |
| if Present (Class_Wide_Type (T)) then |
| return; |
| end if; |
| |
| CW_Type := |
| New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T'); |
| |
| -- Inherit root type characteristics |
| |
| CW_Name := Chars (CW_Type); |
| Next_E := Next_Entity (CW_Type); |
| Copy_Node (T, CW_Type); |
| Set_Comes_From_Source (CW_Type, False); |
| Set_Chars (CW_Type, CW_Name); |
| Set_Parent (CW_Type, Parent (T)); |
| Set_Next_Entity (CW_Type, Next_E); |
| Set_Has_Delayed_Freeze (CW_Type); |
| |
| -- Customize the class-wide type: It has no prim. op., it cannot be |
| -- abstract and its Etype points back to the specific root type. |
| |
| Set_Ekind (CW_Type, E_Class_Wide_Type); |
| Set_Is_Tagged_Type (CW_Type, True); |
| Set_Primitive_Operations (CW_Type, New_Elmt_List); |
| Set_Is_Abstract (CW_Type, False); |
| Set_Is_Constrained (CW_Type, False); |
| Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T)); |
| Init_Size_Align (CW_Type); |
| |
| if Ekind (T) = E_Class_Wide_Subtype then |
| Set_Etype (CW_Type, Etype (Base_Type (T))); |
| else |
| Set_Etype (CW_Type, T); |
| end if; |
| |
| -- If this is the class_wide type of a constrained subtype, it does |
| -- not have discriminants. |
| |
| Set_Has_Discriminants (CW_Type, |
| Has_Discriminants (T) and then not Is_Constrained (T)); |
| |
| Set_Has_Unknown_Discriminants (CW_Type, True); |
| Set_Class_Wide_Type (T, CW_Type); |
| Set_Equivalent_Type (CW_Type, Empty); |
| |
| -- The class-wide type of a class-wide type is itself (RM 3.9(14)) |
| |
| Set_Class_Wide_Type (CW_Type, CW_Type); |
| end Make_Class_Wide_Type; |
| |
| ---------------- |
| -- Make_Index -- |
| ---------------- |
| |
| procedure Make_Index |
| (I : Node_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id := Empty; |
| Suffix_Index : Nat := 1) |
| is |
| R : Node_Id; |
| T : Entity_Id; |
| Def_Id : Entity_Id := Empty; |
| Found : Boolean := False; |
| |
| begin |
| -- For a discrete range used in a constrained array definition and |
| -- defined by a range, an implicit conversion to the predefined type |
| -- INTEGER is assumed if each bound is either a numeric literal, a named |
| -- number, or an attribute, and the type of both bounds (prior to the |
| -- implicit conversion) is the type universal_integer. Otherwise, both |
| -- bounds must be of the same discrete type, other than universal |
| -- integer; this type must be determinable independently of the |
| -- context, but using the fact that the type must be discrete and that |
| -- both bounds must have the same type. |
| |
| -- Character literals also have a universal type in the absence of |
| -- of additional context, and are resolved to Standard_Character. |
| |
| if Nkind (I) = N_Range then |
| |
| -- The index is given by a range constraint. The bounds are known |
| -- to be of a consistent type. |
| |
| if not Is_Overloaded (I) then |
| T := Etype (I); |
| |
| -- If the bounds are universal, choose the specific predefined |
| -- type. |
| |
| if T = Universal_Integer then |
| T := Standard_Integer; |
| |
| elsif T = Any_Character then |
| |
| if Ada_Version >= Ada_95 then |
| Error_Msg_N |
| ("ambiguous character literals (could be Wide_Character)", |
| I); |
| end if; |
| |
| T := Standard_Character; |
| end if; |
| |
| else |
| T := Any_Type; |
| |
| declare |
| Ind : Interp_Index; |
| It : Interp; |
| |
| begin |
| Get_First_Interp (I, Ind, It); |
| while Present (It.Typ) loop |
| if Is_Discrete_Type (It.Typ) then |
| |
| if Found |
| and then not Covers (It.Typ, T) |
| and then not Covers (T, It.Typ) |
| then |
| Error_Msg_N ("ambiguous bounds in discrete range", I); |
| exit; |
| else |
| T := It.Typ; |
| Found := True; |
| end if; |
| end if; |
| |
| Get_Next_Interp (Ind, It); |
| end loop; |
| |
| if T = Any_Type then |
| Error_Msg_N ("discrete type required for range", I); |
| Set_Etype (I, Any_Type); |
| return; |
| |
| elsif T = Universal_Integer then |
| T := Standard_Integer; |
| end if; |
| end; |
| end if; |
| |
| if not Is_Discrete_Type (T) then |
| Error_Msg_N ("discrete type required for range", I); |
| Set_Etype (I, Any_Type); |
| return; |
| end if; |
| |
| if Nkind (Low_Bound (I)) = N_Attribute_Reference |
| and then Attribute_Name (Low_Bound (I)) = Name_First |
| and then Is_Entity_Name (Prefix (Low_Bound (I))) |
| and then Is_Type (Entity (Prefix (Low_Bound (I)))) |
| and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I)))) |
| then |
| -- The type of the index will be the type of the prefix, as long |
| -- as the upper bound is 'Last of the same type. |
| |
| Def_Id := Entity (Prefix (Low_Bound (I))); |
| |
| if Nkind (High_Bound (I)) /= N_Attribute_Reference |
| or else Attribute_Name (High_Bound (I)) /= Name_Last |
| or else not Is_Entity_Name (Prefix (High_Bound (I))) |
| or else Entity (Prefix (High_Bound (I))) /= Def_Id |
| then |
| Def_Id := Empty; |
| end if; |
| end if; |
| |
| R := I; |
| Process_Range_Expr_In_Decl (R, T); |
| |
| elsif Nkind (I) = N_Subtype_Indication then |
| |
| -- The index is given by a subtype with a range constraint |
| |
| T := Base_Type (Entity (Subtype_Mark (I))); |
| |
| if not Is_Discrete_Type (T) then |
| Error_Msg_N ("discrete type required for range", I); |
| Set_Etype (I, Any_Type); |
| return; |
| end if; |
| |
| R := Range_Expression (Constraint (I)); |
| |
| Resolve (R, T); |
| Process_Range_Expr_In_Decl (R, Entity (Subtype_Mark (I))); |
| |
| elsif Nkind (I) = N_Attribute_Reference then |
| |
| -- The parser guarantees that the attribute is a RANGE attribute |
| |
| -- If the node denotes the range of a type mark, that is also the |
| -- resulting type, and we do no need to create an Itype for it. |
| |
| if Is_Entity_Name (Prefix (I)) |
| and then Comes_From_Source (I) |
| and then Is_Type (Entity (Prefix (I))) |
| and then Is_Discrete_Type (Entity (Prefix (I))) |
| then |
| Def_Id := Entity (Prefix (I)); |
| end if; |
| |
| Analyze_And_Resolve (I); |
| T := Etype (I); |
| R := I; |
| |
| -- If none of the above, must be a subtype. We convert this to a |
| -- range attribute reference because in the case of declared first |
| -- named subtypes, the types in the range reference can be different |
| -- from the type of the entity. A range attribute normalizes the |
| -- reference and obtains the correct types for the bounds. |
| |
| -- This transformation is in the nature of an expansion, is only |
| -- done if expansion is active. In particular, it is not done on |
| -- formal generic types, because we need to retain the name of the |
| -- original index for instantiation purposes. |
| |
| else |
| if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then |
| Error_Msg_N ("invalid subtype mark in discrete range ", I); |
| Set_Etype (I, Any_Integer); |
| return; |
| |
| else |
| -- The type mark may be that of an incomplete type. It is only |
| -- now that we can get the full view, previous analysis does |
| -- not look specifically for a type mark. |
| |
| Set_Entity (I, Get_Full_View (Entity (I))); |
| Set_Etype (I, Entity (I)); |
| Def_Id := Entity (I); |
| |
| if not Is_Discrete_Type (Def_Id) then |
| Error_Msg_N ("discrete type required for index", I); |
| Set_Etype (I, Any_Type); |
| return; |
| end if; |
| end if; |
| |
| if Expander_Active then |
| Rewrite (I, |
| Make_Attribute_Reference (Sloc (I), |
| Attribute_Name => Name_Range, |
| Prefix => Relocate_Node (I))); |
| |
| -- The original was a subtype mark that does not freeze. This |
| -- means that the rewritten version must not freeze either. |
| |
| Set_Must_Not_Freeze (I); |
| Set_Must_Not_Freeze (Prefix (I)); |
| |
| -- Is order critical??? if so, document why, if not |
| -- use Analyze_And_Resolve |
| |
| Analyze (I); |
| T := Etype (I); |
| Resolve (I); |
| R := I; |
| |
| -- If expander is inactive, type is legal, nothing else to construct |
| |
| else |
| return; |
| end if; |
| end if; |
| |
| if not Is_Discrete_Type (T) then |
| Error_Msg_N ("discrete type required for range", I); |
| Set_Etype (I, Any_Type); |
| return; |
| |
| elsif T = Any_Type then |
| Set_Etype (I, Any_Type); |
| return; |
| end if; |
| |
| -- We will now create the appropriate Itype to describe the range, but |
| -- first a check. If we originally had a subtype, then we just label |
| -- the range with this subtype. Not only is there no need to construct |
| -- a new subtype, but it is wrong to do so for two reasons: |
| |
| -- 1. A legality concern, if we have a subtype, it must not freeze, |
| -- and the Itype would cause freezing incorrectly |
| |
| -- 2. An efficiency concern, if we created an Itype, it would not be |
| -- recognized as the same type for the purposes of eliminating |
| -- checks in some circumstances. |
| |
| -- We signal this case by setting the subtype entity in Def_Id |
| |
| if No (Def_Id) then |
| Def_Id := |
| Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index); |
| Set_Etype (Def_Id, Base_Type (T)); |
| |
| if Is_Signed_Integer_Type (T) then |
| Set_Ekind (Def_Id, E_Signed_Integer_Subtype); |
| |
| elsif Is_Modular_Integer_Type (T) then |
| Set_Ekind (Def_Id, E_Modular_Integer_Subtype); |
| |
| else |
| Set_Ekind (Def_Id, E_Enumeration_Subtype); |
| Set_Is_Character_Type (Def_Id, Is_Character_Type (T)); |
| Set_First_Literal (Def_Id, First_Literal (T)); |
| end if; |
| |
| Set_Size_Info (Def_Id, (T)); |
| Set_RM_Size (Def_Id, RM_Size (T)); |
| Set_First_Rep_Item (Def_Id, First_Rep_Item (T)); |
| |
| Set_Scalar_Range (Def_Id, R); |
| Conditional_Delay (Def_Id, T); |
| |
| -- In the subtype indication case, if the immediate parent of the |
| -- new subtype is non-static, then the subtype we create is non- |
| -- static, even if its bounds are static. |
| |
| if Nkind (I) = N_Subtype_Indication |
| and then not Is_Static_Subtype (Entity (Subtype_Mark (I))) |
| then |
| Set_Is_Non_Static_Subtype (Def_Id); |
| end if; |
| end if; |
| |
| -- Final step is to label the index with this constructed type |
| |
| Set_Etype (I, Def_Id); |
| end Make_Index; |
| |
| ------------------------------ |
| -- Modular_Type_Declaration -- |
| ------------------------------ |
| |
| procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is |
| Mod_Expr : constant Node_Id := Expression (Def); |
| M_Val : Uint; |
| |
| procedure Set_Modular_Size (Bits : Int); |
| -- Sets RM_Size to Bits, and Esize to normal word size above this |
| |
| ---------------------- |
| -- Set_Modular_Size -- |
| ---------------------- |
| |
| procedure Set_Modular_Size (Bits : Int) is |
| begin |
| Set_RM_Size (T, UI_From_Int (Bits)); |
| |
| if Bits <= 8 then |
| Init_Esize (T, 8); |
| |
| elsif Bits <= 16 then |
| Init_Esize (T, 16); |
| |
| elsif Bits <= 32 then |
| Init_Esize (T, 32); |
| |
| else |
| Init_Esize (T, System_Max_Binary_Modulus_Power); |
| end if; |
| end Set_Modular_Size; |
| |
| -- Start of processing for Modular_Type_Declaration |
| |
| begin |
| Analyze_And_Resolve (Mod_Expr, Any_Integer); |
| Set_Etype (T, T); |
| Set_Ekind (T, E_Modular_Integer_Type); |
| Init_Alignment (T); |
| Set_Is_Constrained (T); |
| |
| if not Is_OK_Static_Expression (Mod_Expr) then |
| Flag_Non_Static_Expr |
| ("non-static expression used for modular type bound!", Mod_Expr); |
| M_Val := 2 ** System_Max_Binary_Modulus_Power; |
| else |
| M_Val := Expr_Value (Mod_Expr); |
| end if; |
| |
| if M_Val < 1 then |
| Error_Msg_N ("modulus value must be positive", Mod_Expr); |
| M_Val := 2 ** System_Max_Binary_Modulus_Power; |
| end if; |
| |
| Set_Modulus (T, M_Val); |
| |
| -- Create bounds for the modular type based on the modulus given in |
| -- the type declaration and then analyze and resolve those bounds. |
| |
| Set_Scalar_Range (T, |
| Make_Range (Sloc (Mod_Expr), |
| Low_Bound => |
| Make_Integer_Literal (Sloc (Mod_Expr), 0), |
| High_Bound => |
| Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1))); |
| |
| -- Properly analyze the literals for the range. We do this manually |
| -- because we can't go calling Resolve, since we are resolving these |
| -- bounds with the type, and this type is certainly not complete yet! |
| |
| Set_Etype (Low_Bound (Scalar_Range (T)), T); |
| Set_Etype (High_Bound (Scalar_Range (T)), T); |
| Set_Is_Static_Expression (Low_Bound (Scalar_Range (T))); |
| Set_Is_Static_Expression (High_Bound (Scalar_Range (T))); |
| |
| -- Loop through powers of two to find number of bits required |
| |
| for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop |
| |
| -- Binary case |
| |
| if M_Val = 2 ** Bits then |
| Set_Modular_Size (Bits); |
| return; |
| |
| -- Non-binary case |
| |
| elsif M_Val < 2 ** Bits then |
| Set_Non_Binary_Modulus (T); |
| |
| if Bits > System_Max_Nonbinary_Modulus_Power then |
| Error_Msg_Uint_1 := |
| UI_From_Int (System_Max_Nonbinary_Modulus_Power); |
| Error_Msg_N |
| ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr); |
| Set_Modular_Size (System_Max_Binary_Modulus_Power); |
| return; |
| |
| else |
| -- In the non-binary case, set size as per RM 13.3(55) |
| |
| Set_Modular_Size (Bits); |
| return; |
| end if; |
| end if; |
| |
| end loop; |
| |
| -- If we fall through, then the size exceed System.Max_Binary_Modulus |
| -- so we just signal an error and set the maximum size. |
| |
| Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power); |
| Error_Msg_N ("modulus exceeds limit (2 '*'*^)", Mod_Expr); |
| |
| Set_Modular_Size (System_Max_Binary_Modulus_Power); |
| Init_Alignment (T); |
| |
| end Modular_Type_Declaration; |
| |
| -------------------------- |
| -- New_Concatenation_Op -- |
| -------------------------- |
| |
| procedure New_Concatenation_Op (Typ : Entity_Id) is |
| Loc : constant Source_Ptr := Sloc (Typ); |
| Op : Entity_Id; |
| |
| function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id; |
| -- Create abbreviated declaration for the formal of a predefined |
| -- Operator 'Op' of type 'Typ' |
| |
| -------------------- |
| -- Make_Op_Formal -- |
| -------------------- |
| |
| function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is |
| Formal : Entity_Id; |
| begin |
| Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P'); |
| Set_Etype (Formal, Typ); |
| Set_Mechanism (Formal, Default_Mechanism); |
| return Formal; |
| end Make_Op_Formal; |
| |
| -- Start of processing for New_Concatenation_Op |
| |
| begin |
| Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat); |
| |
| Set_Ekind (Op, E_Operator); |
| Set_Scope (Op, Current_Scope); |
| Set_Etype (Op, Typ); |
| Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat)); |
| Set_Is_Immediately_Visible (Op); |
| Set_Is_Intrinsic_Subprogram (Op); |
| Set_Has_Completion (Op); |
| Append_Entity (Op, Current_Scope); |
| |
| Set_Name_Entity_Id (Name_Op_Concat, Op); |
| |
| Append_Entity (Make_Op_Formal (Typ, Op), Op); |
| Append_Entity (Make_Op_Formal (Typ, Op), Op); |
| end New_Concatenation_Op; |
| |
| ------------------------------------------- |
| -- Ordinary_Fixed_Point_Type_Declaration -- |
| ------------------------------------------- |
| |
| procedure Ordinary_Fixed_Point_Type_Declaration |
| (T : Entity_Id; |
| Def : Node_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (Def); |
| Delta_Expr : constant Node_Id := Delta_Expression (Def); |
| RRS : constant Node_Id := Real_Range_Specification (Def); |
| Implicit_Base : Entity_Id; |
| Delta_Val : Ureal; |
| Small_Val : Ureal; |
| Low_Val : Ureal; |
| High_Val : Ureal; |
| |
| begin |
| Check_Restriction (No_Fixed_Point, Def); |
| |
| -- Create implicit base type |
| |
| Implicit_Base := |
| Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B'); |
| Set_Etype (Implicit_Base, Implicit_Base); |
| |
| -- Analyze and process delta expression |
| |
| Analyze_And_Resolve (Delta_Expr, Any_Real); |
| |
| Check_Delta_Expression (Delta_Expr); |
| Delta_Val := Expr_Value_R (Delta_Expr); |
| |
| Set_Delta_Value (Implicit_Base, Delta_Val); |
| |
| -- Compute default small from given delta, which is the largest power |
| -- of two that does not exceed the given delta value. |
| |
| declare |
| Tmp : Ureal; |
| Scale : Int; |
| |
| begin |
| Tmp := Ureal_1; |
| Scale := 0; |
| |
| if Delta_Val < Ureal_1 then |
| while Delta_Val < Tmp loop |
| Tmp := Tmp / Ureal_2; |
| Scale := Scale + 1; |
| end loop; |
| |
| else |
| loop |
| Tmp := Tmp * Ureal_2; |
| exit when Tmp > Delta_Val; |
| Scale := Scale - 1; |
| end loop; |
| end if; |
| |
| Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2); |
| end; |
| |
| Set_Small_Value (Implicit_Base, Small_Val); |
| |
| -- If no range was given, set a dummy range |
| |
| if RRS <= Empty_Or_Error then |
| Low_Val := -Small_Val; |
| High_Val := Small_Val; |
| |
| -- Otherwise analyze and process given range |
| |
| else |
| declare |
| Low : constant Node_Id := Low_Bound (RRS); |
| High : constant Node_Id := High_Bound (RRS); |
| |
| begin |
| Analyze_And_Resolve (Low, Any_Real); |
| Analyze_And_Resolve (High, Any_Real); |
| Check_Real_Bound (Low); |
| Check_Real_Bound (High); |
| |
| -- Obtain and set the range |
| |
| Low_Val := Expr_Value_R (Low); |
| High_Val := Expr_Value_R (High); |
| |
| if Low_Val > High_Val then |
| Error_Msg_NE ("?fixed point type& has null range", Def, T); |
| end if; |
| end; |
| end if; |
| |
| -- The range for both the implicit base and the declared first subtype |
| -- cannot be set yet, so we use the special routine Set_Fixed_Range to |
| -- set a temporary range in place. Note that the bounds of the base |
| -- type will be widened to be symmetrical and to fill the available |
| -- bits when the type is frozen. |
| |
| -- We could do this with all discrete types, and probably should, but |
| -- we absolutely have to do it for fixed-point, since the end-points |
| -- of the range and the size are determined by the small value, which |
| -- could be reset before the freeze point. |
| |
| Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val); |
| Set_Fixed_Range (T, Loc, Low_Val, High_Val); |
| |
| Init_Size_Align (Implicit_Base); |
| |
| -- Complete definition of first subtype |
| |
| Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype); |
| Set_Etype (T, Implicit_Base); |
| Init_Size_Align (T); |
| Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base)); |
| Set_Small_Value (T, Small_Val); |
| Set_Delta_Value (T, Delta_Val); |
| Set_Is_Constrained (T); |
| |
| end Ordinary_Fixed_Point_Type_Declaration; |
| |
| ---------------------------------------- |
| -- Prepare_Private_Subtype_Completion -- |
| ---------------------------------------- |
| |
| procedure Prepare_Private_Subtype_Completion |
| (Id : Entity_Id; |
| Related_Nod : Node_Id) |
| is |
| Id_B : constant Entity_Id := Base_Type (Id); |
| Full_B : constant Entity_Id := Full_View (Id_B); |
| Full : Entity_Id; |
| |
| begin |
| if Present (Full_B) then |
| |
| -- The Base_Type is already completed, we can complete the subtype |
| -- now. We have to create a new entity with the same name, Thus we |
| -- can't use Create_Itype. |
| |
| -- This is messy, should be fixed ??? |
| |
| Full := Make_Defining_Identifier (Sloc (Id), Chars (Id)); |
| Set_Is_Itype (Full); |
| Set_Associated_Node_For_Itype (Full, Related_Nod); |
| Complete_Private_Subtype (Id, Full, Full_B, Related_Nod); |
| end if; |
| |
| -- The parent subtype may be private, but the base might not, in some |
| -- nested instances. In that case, the subtype does not need to be |
| -- exchanged. It would still be nice to make private subtypes and their |
| -- bases consistent at all times ??? |
| |
| if Is_Private_Type (Id_B) then |
| Append_Elmt (Id, Private_Dependents (Id_B)); |
| end if; |
| |
| end Prepare_Private_Subtype_Completion; |
| |
| --------------------------- |
| -- Process_Discriminants -- |
| --------------------------- |
| |
| procedure Process_Discriminants |
| (N : Node_Id; |
| Prev : Entity_Id := Empty) |
| is |
| Elist : constant Elist_Id := New_Elmt_List; |
| Id : Node_Id; |
| Discr : Node_Id; |
| Discr_Number : Uint; |
| Discr_Type : Entity_Id; |
| Default_Present : Boolean := False; |
| Default_Not_Present : Boolean := False; |
| |
| begin |
| -- A composite type other than an array type can have discriminants. |
| -- Discriminants of non-limited types must have a discrete type. |
| -- On entry, the current scope is the composite type. |
| |
| -- The discriminants are initially entered into the scope of the type |
| -- via Enter_Name with the default Ekind of E_Void to prevent premature |
| -- use, as explained at the end of this procedure. |
| |
| Discr := First (Discriminant_Specifications (N)); |
| while Present (Discr) loop |
| Enter_Name (Defining_Identifier (Discr)); |
| |
| -- For navigation purposes we add a reference to the discriminant |
| -- in the entity for the type. If the current declaration is a |
| -- completion, place references on the partial view. Otherwise the |
| -- type is the current scope. |
| |
| if Present (Prev) then |
| |
| -- The references go on the partial view, if present. If the |
| -- partial view has discriminants, the references have been |
| -- generated already. |
| |
| if not Has_Discriminants (Prev) then |
| Generate_Reference (Prev, Defining_Identifier (Discr), 'd'); |
| end if; |
| else |
| Generate_Reference |
| (Current_Scope, Defining_Identifier (Discr), 'd'); |
| end if; |
| |
| if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then |
| Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr)); |
| |
| -- Ada 2005 (AI-230): Access discriminants are now allowed for |
| -- nonlimited types, and are treated like other components of |
| -- anonymous access types in terms of accessibility. |
| |
| if not Is_Concurrent_Type (Current_Scope) |
| and then not Is_Concurrent_Record_Type (Current_Scope) |
| and then not Is_Limited_Record (Current_Scope) |
| and then Ekind (Current_Scope) /= E_Limited_Private_Type |
| then |
| Set_Is_Local_Anonymous_Access (Discr_Type); |
| end if; |
| |
| -- Ada 2005 (AI-254) |
| |
| if Present (Access_To_Subprogram_Definition |
| (Discriminant_Type (Discr))) |
| and then Protected_Present (Access_To_Subprogram_Definition |
| (Discriminant_Type (Discr))) |
| then |
| Discr_Type := |
| Replace_Anonymous_Access_To_Protected_Subprogram |
| (Discr, Discr_Type); |
| end if; |
| |
| else |
| Find_Type (Discriminant_Type (Discr)); |
| Discr_Type := Etype (Discriminant_Type (Discr)); |
| |
| if Error_Posted (Discriminant_Type (Discr)) then |
| Discr_Type := Any_Type; |
| end if; |
| end if; |
| |
| if Is_Access_Type (Discr_Type) then |
| |
| -- Ada 2005 (AI-230): Access discriminant allowed in non-limited |
| -- record types |
| |
| if Ada_Version < Ada_05 then |
| Check_Access_Discriminant_Requires_Limited |
| (Discr, Discriminant_Type (Discr)); |
| end if; |
| |
| if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then |
| Error_Msg_N |
| ("(Ada 83) access discriminant not allowed", Discr); |
| end if; |
| |
| elsif not Is_Discrete_Type (Discr_Type) then |
| Error_Msg_N ("discriminants must have a discrete or access type", |
| Discriminant_Type (Discr)); |
| end if; |
| |
| Set_Etype (Defining_Identifier (Discr), Discr_Type); |
| |
| -- If a discriminant specification includes the assignment compound |
| -- delimiter followed by an expression, the expression is the default |
| -- expression of the discriminant; the default expression must be of |
| -- the type of the discriminant. (RM 3.7.1) Since this expression is |
| -- a default expression, we do the special preanalysis, since this |
| -- expression does not freeze (see "Handling of Default and Per- |
| -- Object Expressions" in spec of package Sem). |
| |
| if Present (Expression (Discr)) then |
| Analyze_Per_Use_Expression (Expression (Discr), Discr_Type); |
| |
| if Nkind (N) = N_Formal_Type_Declaration then |
| Error_Msg_N |
| ("discriminant defaults not allowed for formal type", |
| Expression (Discr)); |
| |
| -- Tagged types cannot have defaulted discriminants, but a |
| -- non-tagged private type with defaulted discriminants |
| -- can have a tagged completion. |
| |
| elsif Is_Tagged_Type (Current_Scope) |
| and then Comes_From_Source (N) |
| then |
| Error_Msg_N |
| ("discriminants of tagged type cannot have defaults", |
| Expression (Discr)); |
| |
| else |
| Default_Present := True; |
| Append_Elmt (Expression (Discr), Elist); |
| |
| -- Tag the defining identifiers for the discriminants with |
| -- their corresponding default expressions from the tree. |
| |
| Set_Discriminant_Default_Value |
| (Defining_Identifier (Discr), Expression (Discr)); |
| end if; |
| |
| else |
| Default_Not_Present := True; |
| end if; |
| |
| -- Ada 2005 (AI-231): Create an Itype that is a duplicate of |
| -- Discr_Type but with the null-exclusion attribute |
| |
| if Ada_Version >= Ada_05 then |
| |
| -- Ada 2005 (AI-231): Static checks |
| |
| if Can_Never_Be_Null (Discr_Type) then |
| Null_Exclusion_Static_Checks (Discr); |
| |
| elsif Is_Access_Type (Discr_Type) |
| and then Null_Exclusion_Present (Discr) |
| |
| -- No need to check itypes because in their case this check |
| -- was done at their point of creation |
| |
| and then not Is_Itype (Discr_Type) |
| then |
| if Can_Never_Be_Null (Discr_Type) then |
| Error_Msg_N |
| ("(Ada 2005) already a null-excluding type", Discr); |
| end if; |
| |
| Set_Etype (Defining_Identifier (Discr), |
| Create_Null_Excluding_Itype |
| (T => Discr_Type, |
| Related_Nod => Discr)); |
| end if; |
| |
| end if; |
| |
| Next (Discr); |
| end loop; |
| |
| -- An element list consisting of the default expressions of the |
| -- discriminants is constructed in the above loop and used to set |
| -- the Discriminant_Constraint attribute for the type. If an object |
| -- is declared of this (record or task) type without any explicit |
| -- discriminant constraint given, this element list will form the |
| -- actual parameters for the corresponding initialization procedure |
| -- for the type. |
| |
| Set_Discriminant_Constraint (Current_Scope, Elist); |
| Set_Stored_Constraint (Current_Scope, No_Elist); |
| |
| -- Default expressions must be provided either for all or for none |
| -- of the discriminants of a discriminant part. (RM 3.7.1) |
| |
| if Default_Present and then Default_Not_Present then |
| Error_Msg_N |
| ("incomplete specification of defaults for discriminants", N); |
| end if; |
| |
| -- The use of the name of a discriminant is not allowed in default |
| -- expressions of a discriminant part if the specification of the |
| -- discriminant is itself given in the discriminant part. (RM 3.7.1) |
| |
| -- To detect this, the discriminant names are entered initially with an |
| -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any |
| -- attempt to use a void entity (for example in an expression that is |
| -- type-checked) produces the error message: premature usage. Now after |
| -- completing the semantic analysis of the discriminant part, we can set |
| -- the Ekind of all the discriminants appropriately. |
| |
| Discr := First (Discriminant_Specifications (N)); |
| Discr_Number := Uint_1; |
| while Present (Discr) loop |
| Id := Defining_Identifier (Discr); |
| Set_Ekind (Id, E_Discriminant); |
| Init_Component_Location (Id); |
| Init_Esize (Id); |
| Set_Discriminant_Number (Id, Discr_Number); |
| |
| -- Make sure this is always set, even in illegal programs |
| |
| Set_Corresponding_Discriminant (Id, Empty); |
| |
| -- Initialize the Original_Record_Component to the entity itself. |
| -- Inherit_Components will propagate the right value to |
| -- discriminants in derived record types. |
| |
| Set_Original_Record_Component (Id, Id); |
| |
| -- Create the discriminal for the discriminant |
| |
| Build_Discriminal (Id); |
| |
| Next (Discr); |
| Discr_Number := Discr_Number + 1; |
| end loop; |
| |
| Set_Has_Discriminants (Current_Scope); |
| end Process_Discriminants; |
| |
| ----------------------- |
| -- Process_Full_View -- |
| ----------------------- |
| |
| procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is |
| Priv_Parent : Entity_Id; |
| Full_Parent : Entity_Id; |
| Full_Indic : Node_Id; |
| |
| procedure Collect_Implemented_Interfaces |
| (Typ : Entity_Id; |
| Ifaces : Elist_Id); |
| -- Ada 2005: Gather all the interfaces that Typ directly or |
| -- inherently implements. Duplicate entries are not added to |
| -- the list Ifaces. |
| |
| function Contain_Interface |
| (Iface : Entity_Id; |
| Ifaces : Elist_Id) return Boolean; |
| -- Ada 2005: Determine whether Iface is present in the list Ifaces |
| |
| function Find_Hidden_Interface |
| (Src : Elist_Id; |
| Dest : Elist_Id) return Entity_Id; |
| -- Ada 2005: Determine whether the interfaces in list Src are all |
| -- present in the list Dest. Return the first differing interface, |
| -- or Empty otherwise. |
| |
| ------------------------------------ |
| -- Collect_Implemented_Interfaces -- |
| ------------------------------------ |
| |
| procedure Collect_Implemented_Interfaces |
| (Typ : Entity_Id; |
| Ifaces : Elist_Id) |
| is |
| Iface : Entity_Id; |
| Iface_Elmt : Elmt_Id; |
| |
| begin |
| -- Abstract interfaces are only associated with tagged record types |
| |
| if not Is_Tagged_Type (Typ) |
| or else not Is_Record_Type (Typ) |
| then |
| return; |
| end if; |
| |
| -- Implementations of the form: |
| -- type Typ is new Iface ... |
| |
| if Is_Interface (Etype (Typ)) |
| and then not Contain_Interface (Etype (Typ), Ifaces) |
| then |
| Append_Elmt (Etype (Typ), Ifaces); |
| end if; |
| |
| -- Implementations of the form: |
| -- type Typ is ... and Iface ... |
| |
| if Present (Abstract_Interfaces (Typ)) then |
| Iface_Elmt := First_Elmt (Abstract_Interfaces (Typ)); |
| while Present (Iface_Elmt) loop |
| Iface := Node (Iface_Elmt); |
| |
| pragma Assert (Is_Interface (Iface)); |
| |
| if not Contain_Interface (Iface, Ifaces) then |
| Append_Elmt (Iface, Ifaces); |
| Collect_Implemented_Interfaces (Iface, Ifaces); |
| end if; |
| |
| Next_Elmt (Iface_Elmt); |
| end loop; |
| end if; |
| |
| -- Implementations of the form: |
| -- type Typ is new Parent_Typ and ... |
| |
| if Ekind (Typ) = E_Record_Type |
| and then Present (Parent_Subtype (Typ)) |
| then |
| Collect_Implemented_Interfaces (Parent_Subtype (Typ), Ifaces); |
| |
| -- Implementations of the form: |
| -- type Typ is ... with private; |
| |
| elsif Ekind (Typ) = E_Record_Type_With_Private |
| and then Present (Full_View (Typ)) |
| and then Etype (Typ) /= Full_View (Typ) |
| and then Etype (Typ) /= Typ |
| then |
| Collect_Implemented_Interfaces (Etype (Typ), Ifaces); |
| end if; |
| end Collect_Implemented_Interfaces; |
| |
| ----------------------- |
| -- Contain_Interface -- |
| ----------------------- |
| |
| function Contain_Interface |
| (Iface : Entity_Id; |
| Ifaces : Elist_Id) return Boolean |
| is |
| Iface_Elmt : Elmt_Id; |
| |
| begin |
| if Present (Ifaces) then |
| Iface_Elmt := First_Elmt (Ifaces); |
| while Present (Iface_Elmt) loop |
| if Node (Iface_Elmt) = Iface then |
| return True; |
| end if; |
| |
| Next_Elmt (Iface_Elmt); |
| end loop; |
| end if; |
| |
| return False; |
| end Contain_Interface; |
| |
| --------------------------- |
| -- Find_Hidden_Interface -- |
| --------------------------- |
| |
| function Find_Hidden_Interface |
| (Src : Elist_Id; |
| Dest : Elist_Id) return Entity_Id |
| is |
| Iface : Entity_Id; |
| Iface_Elmt : Elmt_Id; |
| |
| begin |
| if Present (Src) and then Present (Dest) then |
| Iface_Elmt := First_Elmt (Src); |
| while Present (Iface_Elmt) loop |
| Iface := Node (Iface_Elmt); |
| |
| if not Contain_Interface (Iface, Dest) then |
| return Iface; |
| end if; |
| |
| Next_Elmt (Iface_Elmt); |
| end loop; |
| end if; |
| |
| return Empty; |
| end Find_Hidden_Interface; |
| |
| -- Start of processing for Process_Full_View |
| |
| begin |
| -- First some sanity checks that must be done after semantic |
| -- decoration of the full view and thus cannot be placed with other |
| -- similar checks in Find_Type_Name |
| |
| if not Is_Limited_Type (Priv_T) |
| and then (Is_Limited_Type (Full_T) |
| or else Is_Limited_Composite (Full_T)) |
| then |
| Error_Msg_N |
| ("completion of nonlimited type cannot be limited", Full_T); |
| Explain_Limited_Type (Full_T, Full_T); |
| |
| elsif Is_Abstract (Full_T) and then not Is_Abstract (Priv_T) then |
| Error_Msg_N |
| ("completion of nonabstract type cannot be abstract", Full_T); |
| |
| elsif Is_Tagged_Type (Priv_T) |
| and then Is_Limited_Type (Priv_T) |
| and then not Is_Limited_Type (Full_T) |
| then |
| -- GNAT allow its own definition of Limited_Controlled to disobey |
| -- this rule in order in ease the implementation. The next test is |
| -- safe because Root_Controlled is defined in a private system child |
| |
| if Etype (Full_T) = Full_View (RTE (RE_Root_Controlled)) then |
| Set_Is_Limited_Composite (Full_T); |
| else |
| Error_Msg_N |
| ("completion of limited tagged type must be limited", Full_T); |
| end if; |
| |
| elsif Is_Generic_Type (Priv_T) then |
| Error_Msg_N ("generic type cannot have a completion", Full_T); |
| end if; |
| |
| if Ada_Version >= Ada_05 |
| and then Is_Tagged_Type (Priv_T) |
| and then Is_Tagged_Type (Full_T) |
| then |
| declare |
| Iface : Entity_Id; |
| Priv_T_Ifaces : constant Elist_Id := New_Elmt_List; |
| Full_T_Ifaces : constant Elist_Id := New_Elmt_List; |
| |
| begin |
| Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces); |
| Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces); |
| |
| -- Ada 2005 (AI-251): The partial view shall be a descendant of |
| -- an interface type if and only if the full type is descendant |
| -- of the interface type (AARM 7.3 (7.3/2). |
| |
| Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces); |
| |
| if Present (Iface) then |
| Error_Msg_NE ("interface & not implemented by full type " & |
| "('R'M'-2005 7.3 (7.3/2))", Priv_T, Iface); |
| end if; |
| |
| Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces); |
| |
| if Present (Iface) then |
| Error_Msg_NE ("interface & not implemented by partial view " & |
| "('R'M'-2005 7.3 (7.3/2))", Full_T, Iface); |
| end if; |
| end; |
| end if; |
| |
| if Is_Tagged_Type (Priv_T) |
| and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration |
| and then Is_Derived_Type (Full_T) |
| then |
| Priv_Parent := Etype (Priv_T); |
| |
| -- The full view of a private extension may have been transformed |
| -- into an unconstrained derived type declaration and a subtype |
| -- declaration (see build_derived_record_type for details). |
| |
| if Nkind (N) = N_Subtype_Declaration then |
| Full_Indic := Subtype_Indication (N); |
| Full_Parent := Etype (Base_Type (Full_T)); |
| else |
| Full_Indic := Subtype_Indication (Type_Definition (N)); |
| Full_Parent := Etype (Full_T); |
| end if; |
| |
| -- Check that the parent type of the full type is a descendant of |
| -- the ancestor subtype given in the private extension. If either |
| -- entity has an Etype equal to Any_Type then we had some previous |
| -- error situation [7.3(8)]. |
| |
| if Priv_Parent = Any_Type or else Full_Parent = Any_Type then |
| return; |
| |
| -- Ada 2005 (AI-251): Interfaces in the full-typ can be given in |
| -- any order. Therefore we don't have to check that its parent must |
| -- be a descendant of the parent of the private type declaration. |
| |
| elsif Is_Interface (Priv_Parent) |
| and then Is_Interface (Full_Parent) |
| then |
| null; |
| |
| -- Ada 2005 (AI-251): If the parent of the private type declaration |
| -- is an interface there is no need to check that it is an ancestor |
| -- of the associated full type declaration. The required tests for |
| -- this case case are performed by Build_Derived_Record_Type. |
| |
| elsif not Is_Interface (Base_Type (Priv_Parent)) |
| and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent) |
| then |
| Error_Msg_N |
| ("parent of full type must descend from parent" |
| & " of private extension", Full_Indic); |
| |
| -- Check the rules of 7.3(10): if the private extension inherits |
| -- known discriminants, then the full type must also inherit those |
| -- discriminants from the same (ancestor) type, and the parent |
| -- subtype of the full type must be constrained if and only if |
| -- the ancestor subtype of the private extension is constrained. |
| |
| elsif No (Discriminant_Specifications (Parent (Priv_T))) |
| and then not Has_Unknown_Discriminants (Priv_T) |
| and then Has_Discriminants (Base_Type (Priv_Parent)) |
| then |
| declare |
| Priv_Indic : constant Node_Id := |
| Subtype_Indication (Parent (Priv_T)); |
| |
| Priv_Constr : constant Boolean := |
| Is_Constrained (Priv_Parent) |
| or else |
| Nkind (Priv_Indic) = N_Subtype_Indication |
| or else Is_Constrained (Entity (Priv_Indic)); |
| |
| Full_Constr : constant Boolean := |
| Is_Constrained (Full_Parent) |
| or else |
| Nkind (Full_Indic) = N_Subtype_Indication |
| or else Is_Constrained (Entity (Full_Indic)); |
| |
| Priv_Discr : Entity_Id; |
| Full_Discr : Entity_Id; |
| |
| begin |
| Priv_Discr := First_Discriminant (Priv_Parent); |
| Full_Discr := First_Discriminant (Full_Parent); |
| while Present (Priv_Discr) and then Present (Full_Discr) loop |
| if Original_Record_Component (Priv_Discr) = |
| Original_Record_Component (Full_Discr) |
| or else |
| Corresponding_Discriminant (Priv_Discr) = |
| Corresponding_Discriminant (Full_Discr) |
| then |
| null; |
| else |
| exit; |
| end if; |
| |
| Next_Discriminant (Priv_Discr); |
| Next_Discriminant (Full_Discr); |
| end loop; |
| |
| if Present (Priv_Discr) or else Present (Full_Discr) then |
| Error_Msg_N |
| ("full view must inherit discriminants of the parent type" |
| & " used in the private extension", Full_Indic); |
| |
| elsif Priv_Constr and then not Full_Constr then |
| Error_Msg_N |
| ("parent subtype of full type must be constrained", |
| Full_Indic); |
| |
| elsif Full_Constr and then not Priv_Constr then |
| Error_Msg_N |
| ("parent subtype of full type must be unconstrained", |
| Full_Indic); |
| end if; |
| end; |
| |
| -- Check the rules of 7.3(12): if a partial view has neither known |
| -- or unknown discriminants, then the full type declaration shall |
| -- define a definite subtype. |
| |
| elsif not Has_Unknown_Discriminants (Priv_T) |
| and then not Has_Discriminants (Priv_T) |
| and then not Is_Constrained (Full_T) |
| then |
| Error_Msg_N |
| ("full view must define a constrained type if partial view" |
| & " has no discriminants", Full_T); |
| end if; |
| |
| -- ??????? Do we implement the following properly ????? |
| -- If the ancestor subtype of a private extension has constrained |
| -- discriminants, then the parent subtype of the full view shall |
| -- impose a statically matching constraint on those discriminants |
| -- [7.3(13)]. |
| |
| else |
| -- For untagged types, verify that a type without discriminants |
| -- is not completed with an unconstrained type. |
| |
| if not Is_Indefinite_Subtype (Priv_T) |
| and then Is_Indefinite_Subtype (Full_T) |
| then |
| Error_Msg_N ("full view of type must be definite subtype", Full_T); |
| end if; |
| end if; |
| |
| -- AI-419: verify that the use of "limited" is consistent |
| |
| declare |
| Orig_Decl : constant Node_Id := Original_Node (N); |
| begin |
| if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration |
| and then not Limited_Present (Parent (Priv_T)) |
| and then Nkind (Orig_Decl) = N_Full_Type_Declaration |
| and then Nkind |
| (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition |
| and then Limited_Present (Type_Definition (Orig_Decl)) |
| then |
| Error_Msg_N |
| ("full view of non-limited extension cannot be limited", N); |
| end if; |
| end; |
| |
| -- Ada 2005 AI-363: if the full view has discriminants with |
| -- defaults, it is illegal to declare constrained access subtypes |
| -- whose designated type is the current type. This allows objects |
| -- of the type that are declared in the heap to be unconstrained. |
| |
| if not Has_Unknown_Discriminants (Priv_T) |
| and then not Has_Discriminants (Priv_T) |
| and then Has_Discriminants (Full_T) |
| and then |
| Present |
| (Discriminant_Default_Value (First_Discriminant (Full_T))) |
| then |
| Set_Has_Constrained_Partial_View (Full_T); |
| Set_Has_Constrained_Partial_View (Priv_T); |
| end if; |
| |
| -- Create a full declaration for all its subtypes recorded in |
| -- Private_Dependents and swap them similarly to the base type. These |
| -- are subtypes that have been define before the full declaration of |
| -- the private type. We also swap the entry in Private_Dependents list |
| -- so we can properly restore the private view on exit from the scope. |
| |
| declare |
| Priv_Elmt : Elmt_Id; |
| Priv : Entity_Id; |
| Full : Entity_Id; |
| |
| begin |
| Priv_Elmt := First_Elmt (Private_Dependents (Priv_T)); |
| while Present (Priv_Elmt) loop |
| Priv := Node (Priv_Elmt); |
| |
| if Ekind (Priv) = E_Private_Subtype |
| or else Ekind (Priv) = E_Limited_Private_Subtype |
| or else Ekind (Priv) = E_Record_Subtype_With_Private |
| then |
| Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv)); |
| Set_Is_Itype (Full); |
| Set_Parent (Full, Parent (Priv)); |
| Set_Associated_Node_For_Itype (Full, N); |
| |
| -- Now we need to complete the private subtype, but since the |
| -- base type has already been swapped, we must also swap the |
| -- subtypes (and thus, reverse the arguments in the call to |
| -- Complete_Private_Subtype). |
| |
| Copy_And_Swap (Priv, Full); |
| Complete_Private_Subtype (Full, Priv, Full_T, N); |
| Replace_Elmt (Priv_Elmt, Full); |
| end if; |
| |
| Next_Elmt (Priv_Elmt); |
| end loop; |
| end; |
| |
| -- If the private view was tagged, copy the new Primitive |
| -- operations from the private view to the full view. |
| |
| if Is_Tagged_Type (Full_T) then |
| declare |
| Priv_List : Elist_Id; |
| Full_List : constant Elist_Id := Primitive_Operations (Full_T); |
| P1, P2 : Elmt_Id; |
| Prim : Entity_Id; |
| D_Type : Entity_Id; |
| |
| begin |
| if Is_Tagged_Type (Priv_T) then |
| Priv_List := Primitive_Operations (Priv_T); |
| |
| P1 := First_Elmt (Priv_List); |
| while Present (P1) loop |
| Prim := Node (P1); |
| |
| -- Transfer explicit primitives, not those inherited from |
| -- parent of partial view, which will be re-inherited on |
| -- the full view. |
| |
| if Comes_From_Source (Prim) then |
| P2 := First_Elmt (Full_List); |
| while Present (P2) and then Node (P2) /= Prim loop |
| Next_Elmt (P2); |
| end loop; |
| |
| -- If not found, that is a new one |
| |
| if No (P2) then |
| Append_Elmt (Prim, Full_List); |
| end if; |
| end if; |
| |
| Next_Elmt (P1); |
| end loop; |
| |
| else |
| -- In this case the partial view is untagged, so here we |
| -- locate all of the earlier primitives that need to be |
| -- treated as dispatching (those that appear between the two |
| -- views). Note that these additional operations must all be |
| -- new operations (any earlier operations that override |
| -- inherited operations of the full view will already have |
| -- been inserted in the primitives list and marked as |
| -- dispatching by Check_Operation_From_Private_View. Note that |
| -- implicit "/=" operators are excluded from being added to |
| -- the primitives list since they shouldn't be treated as |
| -- dispatching (tagged "/=" is handled specially). |
| |
| Prim := Next_Entity (Full_T); |
| while Present (Prim) and then Prim /= Priv_T loop |
| if Ekind (Prim) = E_Procedure |
| or else |
| Ekind (Prim) = E_Function |
| then |
| |
| D_Type := Find_Dispatching_Type (Prim); |
| |
| if D_Type = Full_T |
| and then (Chars (Prim) /= Name_Op_Ne |
| or else Comes_From_Source (Prim)) |
| then |
| Check_Controlling_Formals (Full_T, Prim); |
| |
| if not Is_Dispatching_Operation (Prim) then |
| Append_Elmt (Prim, Full_List); |
| Set_Is_Dispatching_Operation (Prim, True); |
| Set_DT_Position (Prim, No_Uint); |
| end if; |
| |
| elsif Is_Dispatching_Operation (Prim) |
| and then D_Type /= Full_T |
| then |
| |
| -- Verify that it is not otherwise controlled by |
| -- a formal or a return value of type T. |
| |
| Check_Controlling_Formals (D_Type, Prim); |
| end if; |
| end if; |
| |
| Next_Entity (Prim); |
| end loop; |
| end if; |
| |
| -- For the tagged case, the two views can share the same |
| -- Primitive Operation list and the same class wide type. |
| -- Update attributes of the class-wide type which depend on |
| -- the full declaration. |
| |
| if Is_Tagged_Type (Priv_T) then |
| Set_Primitive_Operations (Priv_T, Full_List); |
| Set_Class_Wide_Type |
| (Base_Type (Full_T), Class_Wide_Type (Priv_T)); |
| |
| -- Any other attributes should be propagated to C_W ??? |
| |
| Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T)); |
| |
| end if; |
| end; |
| end if; |
| end Process_Full_View; |
| |
| ----------------------------------- |
| -- Process_Incomplete_Dependents -- |
| ----------------------------------- |
| |
| procedure Process_Incomplete_Dependents |
| (N : Node_Id; |
| Full_T : Entity_Id; |
| Inc_T : Entity_Id) |
| is |
| Inc_Elmt : Elmt_Id; |
| Priv_Dep : Entity_Id; |
| New_Subt : Entity_Id; |
| |
| Disc_Constraint : Elist_Id; |
| |
| begin |
| if No (Private_Dependents (Inc_T)) then |
| return; |
| end if; |
| |
| -- Itypes that may be generated by the completion of an incomplete |
| -- subtype are not used by the back-end and not attached to the tree. |
| -- They are created only for constraint-checking purposes. |
| |
| Inc_Elmt := First_Elmt (Private_Dependents (Inc_T)); |
| while Present (Inc_Elmt) loop |
| Priv_Dep := Node (Inc_Elmt); |
| |
| if Ekind (Priv_Dep) = E_Subprogram_Type then |
| |
| -- An Access_To_Subprogram type may have a return type or a |
| -- parameter type that is incomplete. Replace with the full view. |
| |
| if Etype (Priv_Dep) = Inc_T then |
| Set_Etype (Priv_Dep, Full_T); |
| end if; |
| |
| declare |
| Formal : Entity_Id; |
| |
| begin |
| Formal := First_Formal (Priv_Dep); |
| while Present (Formal) loop |
| if Etype (Formal) = Inc_T then |
| Set_Etype (Formal, Full_T); |
| end if; |
| |
| Next_Formal (Formal); |
| end loop; |
| end; |
| |
| elsif Is_Overloadable (Priv_Dep) then |
| |
| -- A protected operation is never dispatching: only its |
| -- wrapper operation (which has convention Ada) is. |
| |
| if Is_Tagged_Type (Full_T) |
| and then Convention (Priv_Dep) /= Convention_Protected |
| then |
| |
| -- Subprogram has an access parameter whose designated type |
| -- was incomplete. Reexamine declaration now, because it may |
| -- be a primitive operation of the full type. |
| |
| Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T); |
| Set_Is_Dispatching_Operation (Priv_Dep); |
| Check_Controlling_Formals (Full_T, Priv_Dep); |
| end if; |
| |
| elsif Ekind (Priv_Dep) = E_Subprogram_Body then |
| |
| -- Can happen during processing of a body before the completion |
| -- of a TA type. Ignore, because spec is also on dependent list. |
| |
| return; |
| |
| -- Dependent is a subtype |
| |
| else |
| -- We build a new subtype indication using the full view of the |
| -- incomplete parent. The discriminant constraints have been |
| -- elaborated already at the point of the subtype declaration. |
| |
| New_Subt := Create_Itype (E_Void, N); |
| |
| if Has_Discriminants (Full_T) then |
| Disc_Constraint := Discriminant_Constraint (Priv_Dep); |
| else |
| Disc_Constraint := No_Elist; |
| end if; |
| |
| Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N); |
| Set_Full_View (Priv_Dep, New_Subt); |
| end if; |
| |
| Next_Elmt (Inc_Elmt); |
| end loop; |
| end Process_Incomplete_Dependents; |
| |
| -------------------------------- |
| -- Process_Range_Expr_In_Decl -- |
| -------------------------------- |
| |
| procedure Process_Range_Expr_In_Decl |
| (R : Node_Id; |
| T : Entity_Id; |
| Check_List : List_Id := Empty_List; |
| R_Check_Off : Boolean := False) |
| is |
| Lo, Hi : Node_Id; |
| R_Checks : Check_Result; |
| Type_Decl : Node_Id; |
| Def_Id : Entity_Id; |
| |
| begin |
| Analyze_And_Resolve (R, Base_Type (T)); |
| |
| if Nkind (R) = N_Range then |
| Lo := Low_Bound (R); |
| Hi := High_Bound (R); |
| |
| -- If there were errors in the declaration, try and patch up some |
| -- common mistakes in the bounds. The cases handled are literals |
| -- which are Integer where the expected type is Real and vice versa. |
| -- These corrections allow the compilation process to proceed further |
| -- along since some basic assumptions of the format of the bounds |
| -- are guaranteed. |
| |
| if Etype (R) = Any_Type then |
| |
| if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then |
| Rewrite (Lo, |
| Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo)))); |
| |
| elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then |
| Rewrite (Hi, |
| Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi)))); |
| |
| elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then |
| Rewrite (Lo, |
| Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo)))); |
| |
| elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then |
| Rewrite (Hi, |
| Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi)))); |
| end if; |
| |
| Set_Etype (Lo, T); |
| Set_Etype (Hi, T); |
| end if; |
| |
| -- If the bounds of the range have been mistakenly given as string |
| -- literals (perhaps in place of character literals), then an error |
| -- has already been reported, but we rewrite the string literal as a |
| -- bound of the range's type to avoid blowups in later processing |
| -- that looks at static values. |
| |
| if Nkind (Lo) = N_String_Literal then |
| Rewrite (Lo, |
| Make_Attribute_Reference (Sloc (Lo), |
| Attribute_Name => Name_First, |
| Prefix => New_Reference_To (T, Sloc (Lo)))); |
| Analyze_And_Resolve (Lo); |
| end if; |
| |
| if Nkind (Hi) = N_String_Literal then |
| Rewrite (Hi, |
| Make_Attribute_Reference (Sloc (Hi), |
| Attribute_Name => Name_First, |
| Prefix => New_Reference_To (T, Sloc (Hi)))); |
| Analyze_And_Resolve (Hi); |
| end if; |
| |
| -- If bounds aren't scalar at this point then exit, avoiding |
| -- problems with further processing of the range in this procedure. |
| |
| if not Is_Scalar_Type (Etype (Lo)) then |
| return; |
| end if; |
| |
| -- Resolve (actually Sem_Eval) has checked that the bounds are in |
| -- then range of the base type. Here we check whether the bounds |
| -- are in the range of the subtype itself. Note that if the bounds |
| -- represent the null range the Constraint_Error exception should |
| -- not be raised. |
| |
| -- ??? The following code should be cleaned up as follows |
| |
| -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it |
| -- is done in the call to Range_Check (R, T); below |
| |
| -- 2. The use of R_Check_Off should be investigated and possibly |
| -- removed, this would clean up things a bit. |
| |
| if Is_Null_Range (Lo, Hi) then |
| null; |
| |
| else |
| -- Capture values of bounds and generate temporaries for them |
| -- if needed, before applying checks, since checks may cause |
| -- duplication of the expression without forcing evaluation. |
| |
| if Expander_Active then |
| Force_Evaluation (Lo); |
| Force_Evaluation (Hi); |
| end if; |
| |
| -- We use a flag here instead of suppressing checks on the |
| -- type because the type we check against isn't necessarily |
| -- the place where we put the check. |
| |
| if not R_Check_Off then |
| R_Checks := Range_Check (R, T); |
| |
| -- Look up tree to find an appropriate insertion point. |
| -- This seems really junk code, and very brittle, couldn't |
| -- we just use an insert actions call of some kind ??? |
| |
| Type_Decl := Parent (R); |
| while Present (Type_Decl) and then not |
| (Nkind (Type_Decl) = N_Full_Type_Declaration |
| or else |
| Nkind (Type_Decl) = N_Subtype_Declaration |
| or else |
| Nkind (Type_Decl) = N_Loop_Statement |
| or else |
| Nkind (Type_Decl) = N_Task_Type_Declaration |
| or else |
| Nkind (Type_Decl) = N_Single_Task_Declaration |
| or else |
| Nkind (Type_Decl) = N_Protected_Type_Declaration |
| or else |
| Nkind (Type_Decl) = N_Single_Protected_Declaration) |
| loop |
| Type_Decl := Parent (Type_Decl); |
| end loop; |
| |
| -- Why would Type_Decl not be present??? Without this test, |
| -- short regression tests fail. |
| |
| if Present (Type_Decl) then |
| |
| -- Case of loop statement (more comments ???) |
| |
| if Nkind (Type_Decl) = N_Loop_Statement then |
| declare |
| Indic : Node_Id; |
| |
| begin |
| Indic := Parent (R); |
| while Present (Indic) and then not |
| (Nkind (Indic) = N_Subtype_Indication) |
| loop |
| Indic := Parent (Indic); |
| end loop; |
| |
| if Present (Indic) then |
| Def_Id := Etype (Subtype_Mark (Indic)); |
| |
| Insert_Range_Checks |
| (R_Checks, |
| Type_Decl, |
| Def_Id, |
| Sloc (Type_Decl), |
| R, |
| Do_Before => True); |
| end if; |
| end; |
| |
| -- All other cases (more comments ???) |
| |
| else |
| Def_Id := Defining_Identifier (Type_Decl); |
| |
| if (Ekind (Def_Id) = E_Record_Type |
| and then Depends_On_Discriminant (R)) |
| or else |
| (Ekind (Def_Id) = E_Protected_Type |
| and then Has_Discriminants (Def_Id)) |
| then |
| Append_Range_Checks |
| (R_Checks, Check_List, Def_Id, Sloc (Type_Decl), R); |
| |
| else |
| Insert_Range_Checks |
| (R_Checks, Type_Decl, Def_Id, Sloc (Type_Decl), R); |
| |
| end if; |
| end if; |
| end if; |
| end if; |
| end if; |
| |
| elsif Expander_Active then |
| Get_Index_Bounds (R, Lo, Hi); |
| Force_Evaluation (Lo); |
| Force_Evaluation (Hi); |
| end if; |
| end Process_Range_Expr_In_Decl; |
| |
| -------------------------------------- |
| -- Process_Real_Range_Specification -- |
| -------------------------------------- |
| |
| procedure Process_Real_Range_Specification (Def : Node_Id) is |
| Spec : constant Node_Id := Real_Range_Specification (Def); |
| Lo : Node_Id; |
| Hi : Node_Id; |
| Err : Boolean := False; |
| |
| procedure Analyze_Bound (N : Node_Id); |
| -- Analyze and check one bound |
| |
| ------------------- |
| -- Analyze_Bound -- |
| ------------------- |
| |
| procedure Analyze_Bound (N : Node_Id) is |
| begin |
| Analyze_And_Resolve (N, Any_Real); |
| |
| if not Is_OK_Static_Expression (N) then |
| Flag_Non_Static_Expr |
| ("bound in real type definition is not static!", N); |
| Err := True; |
| end if; |
| end Analyze_Bound; |
| |
| -- Start of processing for Process_Real_Range_Specification |
| |
| begin |
| if Present (Spec) then |
| Lo := Low_Bound (Spec); |
| Hi := High_Bound (Spec); |
| Analyze_Bound (Lo); |
| Analyze_Bound (Hi); |
| |
| -- If error, clear away junk range specification |
| |
| if Err then |
| Set_Real_Range_Specification (Def, Empty); |
| end if; |
| end if; |
| end Process_Real_Range_Specification; |
| |
| --------------------- |
| -- Process_Subtype -- |
| --------------------- |
| |
| function Process_Subtype |
| (S : Node_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id := Empty; |
| Suffix : Character := ' ') return Entity_Id |
| is |
| P : Node_Id; |
| Def_Id : Entity_Id; |
| Error_Node : Node_Id; |
| Full_View_Id : Entity_Id; |
| Subtype_Mark_Id : Entity_Id; |
| |
| May_Have_Null_Exclusion : Boolean; |
| |
| procedure Check_Incomplete (T : Entity_Id); |
| -- Called to verify that an incomplete type is not used prematurely |
| |
| ---------------------- |
| -- Check_Incomplete -- |
| ---------------------- |
| |
| procedure Check_Incomplete (T : Entity_Id) is |
| begin |
| if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type then |
| Error_Msg_N ("invalid use of type before its full declaration", T); |
| end if; |
| end Check_Incomplete; |
| |
| -- Start of processing for Process_Subtype |
| |
| begin |
| -- Case of no constraints present |
| |
| if Nkind (S) /= N_Subtype_Indication then |
| |
| Find_Type (S); |
| Check_Incomplete (S); |
| P := Parent (S); |
| |
| -- Ada 2005 (AI-231): Static check |
| |
| if Ada_Version >= Ada_05 |
| and then Present (P) |
| and then Null_Exclusion_Present (P) |
| and then Nkind (P) /= N_Access_To_Object_Definition |
| and then not Is_Access_Type (Entity (S)) |
| then |
| Error_Msg_N |
| ("(Ada 2005) the null-exclusion part requires an access type", |
| S); |
| end if; |
| |
| May_Have_Null_Exclusion := |
| Nkind (P) = N_Access_Definition |
| or else Nkind (P) = N_Access_Function_Definition |
| or else Nkind (P) = N_Access_Procedure_Definition |
| or else Nkind (P) = N_Access_To_Object_Definition |
| or else Nkind (P) = N_Allocator |
| or else Nkind (P) = N_Component_Definition |
| or else Nkind (P) = N_Derived_Type_Definition |
| or else Nkind (P) = N_Discriminant_Specification |
| or else Nkind (P) = N_Object_Declaration |
| or else Nkind (P) = N_Parameter_Specification |
| or else Nkind (P) = N_Subtype_Declaration; |
| |
| -- Create an Itype that is a duplicate of Entity (S) but with the |
| -- null-exclusion attribute |
| |
| if May_Have_Null_Exclusion |
| and then Is_Access_Type (Entity (S)) |
| and then Null_Exclusion_Present (P) |
| |
| -- No need to check the case of an access to object definition. |
| -- It is correct to define double not-null pointers. |
| -- Example: |
| -- type Not_Null_Int_Ptr is not null access Integer; |
| -- type Acc is not null access Not_Null_Int_Ptr; |
| |
| and then Nkind (P) /= N_Access_To_Object_Definition |
| then |
| if Can_Never_Be_Null (Entity (S)) then |
| case Nkind (Related_Nod) is |
| when N_Full_Type_Declaration => |
| if Nkind (Type_Definition (Related_Nod)) |
| in N_Array_Type_Definition |
| then |
| Error_Node := |
| Subtype_Indication |
| (Component_Definition |
| (Type_Definition (Related_Nod))); |
| else |
| Error_Node := |
| Subtype_Indication (Type_Definition (Related_Nod)); |
| end if; |
| |
| when N_Subtype_Declaration => |
| Error_Node := Subtype_Indication (Related_Nod); |
| |
| when N_Object_Declaration => |
| Error_Node := Object_Definition (Related_Nod); |
| |
| when N_Component_Declaration => |
| Error_Node := |
| Subtype_Indication (Component_Definition (Related_Nod)); |
| |
| when others => |
| pragma Assert (False); |
| Error_Node := Related_Nod; |
| end case; |
| |
| Error_Msg_N |
| ("(Ada 2005) already a null-excluding type", Error_Node); |
| end if; |
| |
| Set_Etype (S, |
| Create_Null_Excluding_Itype |
| (T => Entity (S), |
| Related_Nod => P)); |
| Set_Entity (S, Etype (S)); |
| end if; |
| |
| return Entity (S); |
| |
| -- Case of constraint present, so that we have an N_Subtype_Indication |
| -- node (this node is created only if constraints are present). |
| |
| else |
| |
| Find_Type (Subtype_Mark (S)); |
| |
| if Nkind (Parent (S)) /= N_Access_To_Object_Definition |
| and then not |
| (Nkind (Parent (S)) = N_Subtype_Declaration |
| and then Is_Itype (Defining_Identifier (Parent (S)))) |
| then |
| Check_Incomplete (Subtype_Mark (S)); |
| end if; |
| |
| P := Parent (S); |
| Subtype_Mark_Id := Entity (Subtype_Mark (S)); |
| |
| -- Explicit subtype declaration case |
| |
| if Nkind (P) = N_Subtype_Declaration then |
| Def_Id := Defining_Identifier (P); |
| |
| -- Explicit derived type definition case |
| |
| elsif Nkind (P) = N_Derived_Type_Definition then |
| Def_Id := Defining_Identifier (Parent (P)); |
| |
| -- Implicit case, the Def_Id must be created as an implicit type. |
| -- The one exception arises in the case of concurrent types, array |
| -- and access types, where other subsidiary implicit types may be |
| -- created and must appear before the main implicit type. In these |
| -- cases we leave Def_Id set to Empty as a signal that Create_Itype |
| -- has not yet been called to create Def_Id. |
| |
| else |
| if Is_Array_Type (Subtype_Mark_Id) |
| or else Is_Concurrent_Type (Subtype_Mark_Id) |
| or else Is_Access_Type (Subtype_Mark_Id) |
| then |
| Def_Id := Empty; |
| |
| -- For the other cases, we create a new unattached Itype, |
| -- and set the indication to ensure it gets attached later. |
| |
| else |
| Def_Id := |
| Create_Itype (E_Void, Related_Nod, Related_Id, Suffix); |
| end if; |
| end if; |
| |
| -- If the kind of constraint is invalid for this kind of type, |
| -- then give an error, and then pretend no constraint was given. |
| |
| if not Is_Valid_Constraint_Kind |
| (Ekind (Subtype_Mark_Id), Nkind (Constraint (S))) |
| then |
| Error_Msg_N |
| ("incorrect constraint for this kind of type", Constraint (S)); |
| |
| Rewrite (S, New_Copy_Tree (Subtype_Mark (S))); |
| |
| -- Set Ekind of orphan itype, to prevent cascaded errors |
| |
| if Present (Def_Id) then |
| Set_Ekind (Def_Id, Ekind (Any_Type)); |
| end if; |
| |
| -- Make recursive call, having got rid of the bogus constraint |
| |
| return Process_Subtype (S, Related_Nod, Related_Id, Suffix); |
| end if; |
| |
| -- Remaining processing depends on type |
| |
| case Ekind (Subtype_Mark_Id) is |
| when Access_Kind => |
| Constrain_Access (Def_Id, S, Related_Nod); |
| |
| when Array_Kind => |
| Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix); |
| |
| when Decimal_Fixed_Point_Kind => |
| Constrain_Decimal (Def_Id, S); |
| |
| when Enumeration_Kind => |
| Constrain_Enumeration (Def_Id, S); |
| |
| when Ordinary_Fixed_Point_Kind => |
| Constrain_Ordinary_Fixed (Def_Id, S); |
| |
| when Float_Kind => |
| Constrain_Float (Def_Id, S); |
| |
| when Integer_Kind => |
| Constrain_Integer (Def_Id, S); |
| |
| when E_Record_Type | |
| E_Record_Subtype | |
| Class_Wide_Kind | |
| E_Incomplete_Type => |
| Constrain_Discriminated_Type (Def_Id, S, Related_Nod); |
| |
| when Private_Kind => |
| Constrain_Discriminated_Type (Def_Id, S, Related_Nod); |
| Set_Private_Dependents (Def_Id, New_Elmt_List); |
| |
| -- In case of an invalid constraint prevent further processing |
| -- since the type constructed is missing expected fields. |
| |
| if Etype (Def_Id) = Any_Type then |
| return Def_Id; |
| end if; |
| |
| -- If the full view is that of a task with discriminants, |
| -- we must constrain both the concurrent type and its |
| -- corresponding record type. Otherwise we will just propagate |
| -- the constraint to the full view, if available. |
| |
| if Present (Full_View (Subtype_Mark_Id)) |
| and then Has_Discriminants (Subtype_Mark_Id) |
| and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id)) |
| then |
| Full_View_Id := |
| Create_Itype (E_Void, Related_Nod, Related_Id, Suffix); |
| |
| Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id)); |
| Constrain_Concurrent (Full_View_Id, S, |
| Related_Nod, Related_Id, Suffix); |
| Set_Entity (Subtype_Mark (S), Subtype_Mark_Id); |
| Set_Full_View (Def_Id, Full_View_Id); |
| |
| else |
| Prepare_Private_Subtype_Completion (Def_Id, Related_Nod); |
| end if; |
| |
| when Concurrent_Kind => |
| Constrain_Concurrent (Def_Id, S, |
| Related_Nod, Related_Id, Suffix); |
| |
| when others => |
| Error_Msg_N ("invalid subtype mark in subtype indication", S); |
| end case; |
| |
| -- Size and Convention are always inherited from the base type |
| |
| Set_Size_Info (Def_Id, (Subtype_Mark_Id)); |
| Set_Convention (Def_Id, Convention (Subtype_Mark_Id)); |
| |
| return Def_Id; |
| end if; |
| end Process_Subtype; |
| |
| ----------------------------- |
| -- Record_Type_Declaration -- |
| ----------------------------- |
| |
| procedure Record_Type_Declaration |
| (T : Entity_Id; |
| N : Node_Id; |
| Prev : Entity_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| Def : constant Node_Id := Type_Definition (N); |
| Inc_T : Entity_Id := Empty; |
| |
| Is_Tagged : Boolean; |
| Tag_Comp : Entity_Id; |
| |
| procedure Check_Anonymous_Access_Types (Comp_List : Node_Id); |
| -- Ada 2005 AI-382: an access component in a record declaration can |
| -- refer to the enclosing record, in which case it denotes the type |
| -- itself, and not the current instance of the type. We create an |
| -- anonymous access type for the component, and flag it as an access |
| -- to a component, so that accessibility checks are properly performed |
| -- on it. The declaration of the access type is placed ahead of that |
| -- of the record, to prevent circular order-of-elaboration issues in |
| -- Gigi. We create an incomplete type for the record declaration, which |
| -- is the designated type of the anonymous access. |
| |
| procedure Make_Incomplete_Type_Declaration; |
| -- If the record type contains components that include an access to the |
| -- current record, create an incomplete type declaration for the record, |
| -- to be used as the designated type of the anonymous access. This is |
| -- done only once, and only if there is no previous partial view of the |
| -- type. |
| |
| ---------------------------------- |
| -- Check_Anonymous_Access_Types -- |
| ---------------------------------- |
| |
| procedure Check_Anonymous_Access_Types (Comp_List : Node_Id) is |
| Anon_Access : Entity_Id; |
| Acc_Def : Node_Id; |
| Comp : Node_Id; |
| Decl : Node_Id; |
| Type_Def : Node_Id; |
| |
| function Mentions_T (Acc_Def : Node_Id) return Boolean; |
| -- Check whether an access definition includes a reference to |
| -- the enclosing record type. The reference can be a subtype |
| -- mark in the access definition itself, or a 'Class attribute |
| -- reference, or recursively a reference appearing in a parameter |
| -- type in an access_to_subprogram definition. |
| |
| ---------------- |
| -- Mentions_T -- |
| ---------------- |
| |
| function Mentions_T (Acc_Def : Node_Id) return Boolean is |
| Subt : Node_Id; |
| |
| begin |
| if No (Access_To_Subprogram_Definition (Acc_Def)) then |
| Subt := Subtype_Mark (Acc_Def); |
| |
| if Nkind (Subt) = N_Identifier then |
| return Chars (Subt) = Chars (T); |
| |
| -- A reference to the current type may appear as the prefix |
| -- of a 'Class attribute. |
| |
| elsif Nkind (Subt) = N_Attribute_Reference |
| and then Attribute_Name (Subt) = Name_Class |
| and then Is_Entity_Name (Prefix (Subt)) |
| then |
| return (Chars (Prefix (Subt))) = Chars (T); |
| else |
| return False; |
| end if; |
| |
| else |
| -- Component is an access_to_subprogram: examine its formals |
| |
| declare |
| Param_Spec : Node_Id; |
| |
| begin |
| Param_Spec := |
| First |
| (Parameter_Specifications |
| (Access_To_Subprogram_Definition (Acc_Def))); |
| while Present (Param_Spec) loop |
| if Nkind (Parameter_Type (Param_Spec)) |
| = N_Access_Definition |
| and then Mentions_T (Parameter_Type (Param_Spec)) |
| then |
| return True; |
| end if; |
| |
| Next (Param_Spec); |
| end loop; |
| |
| return False; |
| end; |
| end if; |
| end Mentions_T; |
| |
| -- Start of processing for Check_Anonymous_Access_Types |
| |
| begin |
| if No (Comp_List) then |
| return; |
| end if; |
| |
| Comp := First (Component_Items (Comp_List)); |
| while Present (Comp) loop |
| if Nkind (Comp) = N_Component_Declaration |
| and then |
| Present (Access_Definition (Component_Definition (Comp))) |
| and then |
| Mentions_T (Access_Definition (Component_Definition (Comp))) |
| then |
| Acc_Def := |
| Access_To_Subprogram_Definition |
| (Access_Definition (Component_Definition (Comp))); |
| |
| Make_Incomplete_Type_Declaration; |
| Anon_Access := |
| Make_Defining_Identifier (Loc, |
| Chars => New_Internal_Name ('S')); |
| |
| -- Create a declaration for the anonymous access type: either |
| -- an access_to_object or an access_to_subprogram. |
| |
| if Present (Acc_Def) then |
| if Nkind (Acc_Def) = N_Access_Function_Definition then |
| Type_Def := |
| Make_Access_Function_Definition (Loc, |
| Parameter_Specifications => |
| Parameter_Specifications (Acc_Def), |
| Result_Definition => Result_Definition (Acc_Def)); |
| else |
| Type_Def := |
| Make_Access_Procedure_Definition (Loc, |
| Parameter_Specifications => |
| Parameter_Specifications (Acc_Def)); |
| end if; |
| |
| else |
| Type_Def := |
| Make_Access_To_Object_Definition (Loc, |
| Subtype_Indication => |
| Relocate_Node |
| (Subtype_Mark |
| (Access_Definition |
| (Component_Definition (Comp))))); |
| end if; |
| |
| Decl := Make_Full_Type_Declaration (Loc, |
| Defining_Identifier => Anon_Access, |
| Type_Definition => Type_Def); |
| |
| Insert_Before (N, Decl); |
| Analyze (Decl); |
| |
| Rewrite (Component_Definition (Comp), |
| Make_Component_Definition (Loc, |
| Subtype_Indication => |
| New_Occurrence_Of (Anon_Access, Loc))); |
| Set_Ekind (Anon_Access, E_Anonymous_Access_Type); |
| Set_Is_Local_Anonymous_Access (Anon_Access); |
| end if; |
| |
| Next (Comp); |
| end loop; |
| |
| if Present (Variant_Part (Comp_List)) then |
| declare |
| V : Node_Id; |
| begin |
| V := First_Non_Pragma (Variants (Variant_Part (Comp_List))); |
| while Present (V) loop |
| Check_Anonymous_Access_Types (Component_List (V)); |
| Next_Non_Pragma (V); |
| end loop; |
| end; |
| end if; |
| end Check_Anonymous_Access_Types; |
| |
| -------------------------------------- |
| -- Make_Incomplete_Type_Declaration -- |
| -------------------------------------- |
| |
| procedure Make_Incomplete_Type_Declaration is |
| Decl : Node_Id; |
| H : Entity_Id; |
| |
| begin |
| -- If there is a previous partial view, no need to create a new one |
| -- If the partial view is incomplete, it is given by Prev. If it is |
| -- a private declaration, full declaration is flagged accordingly. |
| |
| if Prev /= T |
| or else Has_Private_Declaration (T) |
| then |
| return; |
| |
| elsif No (Inc_T) then |
| Inc_T := Make_Defining_Identifier (Loc, Chars (T)); |
| Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T); |
| |
| -- Type has already been inserted into the current scope. |
| -- Remove it, and add incomplete declaration for type, so |
| -- that subsequent anonymous access types can use it. |
| |
| H := Current_Entity (T); |
| |
| if H = T then |
| Set_Name_Entity_Id (Chars (T), Empty); |
| else |
| while Present (H) |
| and then Homonym (H) /= T |
| loop |
| H := Homonym (T); |
| end loop; |
| |
| Set_Homonym (H, Homonym (T)); |
| end if; |
| |
| Insert_Before (N, Decl); |
| Analyze (Decl); |
| Set_Full_View (Inc_T, T); |
| |
| if Tagged_Present (Def) then |
| Make_Class_Wide_Type (Inc_T); |
| Set_Class_Wide_Type (T, Class_Wide_Type (Inc_T)); |
| Set_Etype (Class_Wide_Type (T), T); |
| end if; |
| end if; |
| end Make_Incomplete_Type_Declaration; |
| |
| -- Start of processing for Record_Type_Declaration |
| |
| begin |
| -- These flags must be initialized before calling Process_Discriminants |
| -- because this routine makes use of them. |
| |
| Set_Ekind (T, E_Record_Type); |
| Set_Etype (T, T); |
| Init_Size_Align (T); |
| Set_Abstract_Interfaces (T, No_Elist); |
| Set_Stored_Constraint (T, No_Elist); |
| |
| -- Normal case |
| |
| if Ada_Version < Ada_05 |
| or else not Interface_Present (Def) |
| then |
| -- The flag Is_Tagged_Type might have already been set by |
| -- Find_Type_Name if it detected an error for declaration T. This |
| -- arises in the case of private tagged types where the full view |
| -- omits the word tagged. |
| |
| Is_Tagged := |
| Tagged_Present (Def) |
| or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T)); |
| |
| Set_Is_Tagged_Type (T, Is_Tagged); |
| Set_Is_Limited_Record (T, Limited_Present (Def)); |
| |
| -- Type is abstract if full declaration carries keyword, or if |
| -- previous partial view did. |
| |
| Set_Is_Abstract (T, Is_Abstract (T) |
| or else Abstract_Present (Def)); |
| |
| else |
| Is_Tagged := True; |
| Analyze_Interface_Declaration (T, Def); |
| end if; |
| |
| -- First pass: if there are self-referential access components, |
| -- create the required anonymous access type declarations, and if |
| -- need be an incomplete type declaration for T itself. |
| |
| Check_Anonymous_Access_Types (Component_List (Def)); |
| |
| if Ada_Version >= Ada_05 |
| and then Present (Interface_List (Def)) |
| then |
| declare |
| Iface : Node_Id; |
| Iface_Def : Node_Id; |
| Iface_Typ : Entity_Id; |
| |
| begin |
| Iface := First (Interface_List (Def)); |
| while Present (Iface) loop |
| Iface_Typ := Find_Type_Of_Subtype_Indic (Iface); |
| Iface_Def := Type_Definition (Parent (Iface_Typ)); |
| |
| if not Is_Interface (Iface_Typ) then |
| Error_Msg_NE ("(Ada 2005) & must be an interface", |
| Iface, Iface_Typ); |
| |
| else |
| -- "The declaration of a specific descendant of an |
| -- interface type freezes the interface type" RM 13.14 |
| |
| Freeze_Before (N, Iface_Typ); |
| |
| -- Ada 2005 (AI-345): Protected interfaces can only |
| -- inherit from limited, synchronized or protected |
| -- interfaces. |
| |
| if Protected_Present (Def) then |
| if Limited_Present (Iface_Def) |
| or else Synchronized_Present (Iface_Def) |
| or else Protected_Present (Iface_Def) |
| then |
| null; |
| |
| elsif Task_Present (Iface_Def) then |
| Error_Msg_N ("(Ada 2005) protected interface cannot" |
| & " inherit from task interface", Iface); |
| |
| else |
| Error_Msg_N ("(Ada 2005) protected interface cannot" |
| & " inherit from non-limited interface", Iface); |
| end if; |
| |
| -- Ada 2005 (AI-345): Synchronized interfaces can only |
| -- inherit from limited and synchronized. |
| |
| elsif Synchronized_Present (Def) then |
| if Limited_Present (Iface_Def) |
| or else Synchronized_Present (Iface_Def) |
| then |
| null; |
| |
| elsif Protected_Present (Iface_Def) then |
| Error_Msg_N ("(Ada 2005) synchronized interface " & |
| "cannot inherit from protected interface", Iface); |
| |
| elsif Task_Present (Iface_Def) then |
| Error_Msg_N ("(Ada 2005) synchronized interface " & |
| "cannot inherit from task interface", Iface); |
| |
| else |
| Error_Msg_N ("(Ada 2005) synchronized interface " & |
| "cannot inherit from non-limited interface", |
| Iface); |
| end if; |
| |
| -- Ada 2005 (AI-345): Task interfaces can only inherit |
| -- from limited, synchronized or task interfaces. |
| |
| elsif Task_Present (Def) then |
| if Limited_Present (Iface_Def) |
| or else Synchronized_Present (Iface_Def) |
| or else Task_Present (Iface_Def) |
| then |
| null; |
| |
| elsif Protected_Present (Iface_Def) then |
| Error_Msg_N ("(Ada 2005) task interface cannot" & |
| " inherit from protected interface", Iface); |
| |
| else |
| Error_Msg_N ("(Ada 2005) task interface cannot" & |
| " inherit from non-limited interface", Iface); |
| end if; |
| end if; |
| end if; |
| |
| Next (Iface); |
| end loop; |
| Set_Abstract_Interfaces (T, New_Elmt_List); |
| Collect_Interfaces (Def, T); |
| end; |
| end if; |
| |
| -- Records constitute a scope for the component declarations within. |
| -- The scope is created prior to the processing of these declarations. |
| -- Discriminants are processed first, so that they are visible when |
| -- processing the other components. The Ekind of the record type itself |
| -- is set to E_Record_Type (subtypes appear as E_Record_Subtype). |
| |
| -- Enter record scope |
| |
| New_Scope (T); |
| |
| -- If an incomplete or private type declaration was already given for |
| -- the type, then this scope already exists, and the discriminants have |
| -- been declared within. We must verify that the full declaration |
| -- matches the incomplete one. |
| |
| Check_Or_Process_Discriminants (N, T, Prev); |
| |
| Set_Is_Constrained (T, not Has_Discriminants (T)); |
| Set_Has_Delayed_Freeze (T, True); |
| |
| -- For tagged types add a manually analyzed component corresponding |
| -- to the component _tag, the corresponding piece of tree will be |
| -- expanded as part of the freezing actions if it is not a CPP_Class. |
| |
| if Is_Tagged then |
| |
| -- Do not add the tag unless we are in expansion mode |
| |
| if Expander_Active then |
| Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag); |
| Enter_Name (Tag_Comp); |
| |
| Set_Is_Tag (Tag_Comp); |
| Set_Is_Aliased (Tag_Comp); |
| Set_Ekind (Tag_Comp, E_Component); |
| Set_Etype (Tag_Comp, RTE (RE_Tag)); |
| Set_DT_Entry_Count (Tag_Comp, No_Uint); |
| Set_Original_Record_Component (Tag_Comp, Tag_Comp); |
| Init_Component_Location (Tag_Comp); |
| |
| -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the |
| -- implemented interfaces |
| |
| Add_Interface_Tag_Components (N, T); |
| end if; |
| |
| Make_Class_Wide_Type (T); |
| Set_Primitive_Operations (T, New_Elmt_List); |
| end if; |
| |
| -- We must suppress range checks when processing the components |
| -- of a record in the presence of discriminants, since we don't |
| -- want spurious checks to be generated during their analysis, but |
| -- must reset the Suppress_Range_Checks flags after having processed |
| -- the record definition. |
| |
| if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then |
| Set_Kill_Range_Checks (T, True); |
| Record_Type_Definition (Def, Prev); |
| Set_Kill_Range_Checks (T, False); |
| else |
| Record_Type_Definition (Def, Prev); |
| end if; |
| |
| -- Exit from record scope |
| |
| End_Scope; |
| |
| if Expander_Active |
| and then Is_Tagged |
| and then not Is_Empty_List (Interface_List (Def)) |
| then |
| -- Ada 2005 (AI-251): Derive the interface subprograms of all the |
| -- implemented interfaces and check if some of the subprograms |
| -- inherited from the ancestor cover some interface subprogram. |
| |
| Derive_Interface_Subprograms (T); |
| end if; |
| end Record_Type_Declaration; |
| |
| ---------------------------- |
| -- Record_Type_Definition -- |
| ---------------------------- |
| |
| procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is |
| Component : Entity_Id; |
| Ctrl_Components : Boolean := False; |
| Final_Storage_Only : Boolean; |
| T : Entity_Id; |
| |
| begin |
| if Ekind (Prev_T) = E_Incomplete_Type then |
| T := Full_View (Prev_T); |
| else |
| T := Prev_T; |
| end if; |
| |
| Final_Storage_Only := not Is_Controlled (T); |
| |
| -- Ada 2005: check whether an explicit Limited is present in a derived |
| -- type declaration. |
| |
| if Nkind (Parent (Def)) = N_Derived_Type_Definition |
| and then Limited_Present (Parent (Def)) |
| then |
| Set_Is_Limited_Record (T); |
| end if; |
| |
| -- If the component list of a record type is defined by the reserved |
| -- word null and there is no discriminant part, then the record type has |
| -- no components and all records of the type are null records (RM 3.7) |
| -- This procedure is also called to process the extension part of a |
| -- record extension, in which case the current scope may have inherited |
| -- components. |
| |
| if No (Def) |
| or else No (Component_List (Def)) |
| or else Null_Present (Component_List (Def)) |
| then |
| null; |
| |
| else |
| Analyze_Declarations (Component_Items (Component_List (Def))); |
| |
| if Present (Variant_Part (Component_List (Def))) then |
| Analyze (Variant_Part (Component_List (Def))); |
| end if; |
| end if; |
| |
| -- After completing the semantic analysis of the record definition, |
| -- record components, both new and inherited, are accessible. Set |
| -- their kind accordingly. |
| |
| Component := First_Entity (Current_Scope); |
| while Present (Component) loop |
| if Ekind (Component) = E_Void then |
| Set_Ekind (Component, E_Component); |
| Init_Component_Location (Component); |
| end if; |
| |
| if Has_Task (Etype (Component)) then |
| Set_Has_Task (T); |
| end if; |
| |
| if Ekind (Component) /= E_Component then |
| null; |
| |
| elsif Has_Controlled_Component (Etype (Component)) |
| or else (Chars (Component) /= Name_uParent |
| and then Is_Controlled (Etype (Component))) |
| then |
| Set_Has_Controlled_Component (T, True); |
| Final_Storage_Only := Final_Storage_Only |
| and then Finalize_Storage_Only (Etype (Component)); |
| Ctrl_Components := True; |
| end if; |
| |
| Next_Entity (Component); |
| end loop; |
| |
| -- A type is Finalize_Storage_Only only if all its controlled |
| -- components are so. |
| |
| if Ctrl_Components then |
| Set_Finalize_Storage_Only (T, Final_Storage_Only); |
| end if; |
| |
| -- Place reference to end record on the proper entity, which may |
| -- be a partial view. |
| |
| if Present (Def) then |
| Process_End_Label (Def, 'e', Prev_T); |
| end if; |
| end Record_Type_Definition; |
| |
| ------------------------ |
| -- Replace_Components -- |
| ------------------------ |
| |
| procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is |
| function Process (N : Node_Id) return Traverse_Result; |
| |
| ------------- |
| -- Process -- |
| ------------- |
| |
| function Process (N : Node_Id) return Traverse_Result is |
| Comp : Entity_Id; |
| |
| begin |
| if Nkind (N) = N_Discriminant_Specification then |
| Comp := First_Discriminant (Typ); |
| while Present (Comp) loop |
| if Chars (Comp) = Chars (Defining_Identifier (N)) then |
| Set_Defining_Identifier (N, Comp); |
| exit; |
| end if; |
| |
| Next_Discriminant (Comp); |
| end loop; |
| |
| elsif Nkind (N) = N_Component_Declaration then |
| Comp := First_Component (Typ); |
| while Present (Comp) loop |
| if Chars (Comp) = Chars (Defining_Identifier (N)) then |
| Set_Defining_Identifier (N, Comp); |
| exit; |
| end if; |
| |
| Next_Component (Comp); |
| end loop; |
| end if; |
| |
| return OK; |
| end Process; |
| |
| procedure Replace is new Traverse_Proc (Process); |
| |
| -- Start of processing for Replace_Components |
| |
| begin |
| Replace (Decl); |
| end Replace_Components; |
| |
| ------------------------------- |
| -- Set_Completion_Referenced -- |
| ------------------------------- |
| |
| procedure Set_Completion_Referenced (E : Entity_Id) is |
| begin |
| -- If in main unit, mark entity that is a completion as referenced, |
| -- warnings go on the partial view when needed. |
| |
| if In_Extended_Main_Source_Unit (E) then |
| Set_Referenced (E); |
| end if; |
| end Set_Completion_Referenced; |
| |
| --------------------- |
| -- Set_Fixed_Range -- |
| --------------------- |
| |
| -- The range for fixed-point types is complicated by the fact that we |
| -- do not know the exact end points at the time of the declaration. This |
| -- is true for three reasons: |
| |
| -- A size clause may affect the fudging of the end-points |
| -- A small clause may affect the values of the end-points |
| -- We try to include the end-points if it does not affect the size |
| |
| -- This means that the actual end-points must be established at the point |
| -- when the type is frozen. Meanwhile, we first narrow the range as |
| -- permitted (so that it will fit if necessary in a small specified size), |
| -- and then build a range subtree with these narrowed bounds. |
| |
| -- Set_Fixed_Range constructs the range from real literal values, and sets |
| -- the range as the Scalar_Range of the given fixed-point type entity. |
| |
| -- The parent of this range is set to point to the entity so that it is |
| -- properly hooked into the tree (unlike normal Scalar_Range entries for |
| -- other scalar types, which are just pointers to the range in the |
| -- original tree, this would otherwise be an orphan). |
| |
| -- The tree is left unanalyzed. When the type is frozen, the processing |
| -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not |
| -- analyzed, and uses this as an indication that it should complete |
| -- work on the range (it will know the final small and size values). |
| |
| procedure Set_Fixed_Range |
| (E : Entity_Id; |
| Loc : Source_Ptr; |
| Lo : Ureal; |
| Hi : Ureal) |
| is |
| S : constant Node_Id := |
| Make_Range (Loc, |
| Low_Bound => Make_Real_Literal (Loc, Lo), |
| High_Bound => Make_Real_Literal (Loc, Hi)); |
| |
| begin |
| Set_Scalar_Range (E, S); |
| Set_Parent (S, E); |
| end Set_Fixed_Range; |
| |
| ---------------------------------- |
| -- Set_Scalar_Range_For_Subtype -- |
| ---------------------------------- |
| |
| procedure Set_Scalar_Range_For_Subtype |
| (Def_Id : Entity_Id; |
| R : Node_Id; |
| Subt : Entity_Id) |
| is |
| Kind : constant Entity_Kind := Ekind (Def_Id); |
| |
| begin |
| Set_Scalar_Range (Def_Id, R); |
| |
| -- We need to link the range into the tree before resolving it so |
| -- that types that are referenced, including importantly the subtype |
| -- itself, are properly frozen (Freeze_Expression requires that the |
| -- expression be properly linked into the tree). Of course if it is |
| -- already linked in, then we do not disturb the current link. |
| |
| if No (Parent (R)) then |
| Set_Parent (R, Def_Id); |
| end if; |
| |
| -- Reset the kind of the subtype during analysis of the range, to |
| -- catch possible premature use in the bounds themselves. |
| |
| Set_Ekind (Def_Id, E_Void); |
| Process_Range_Expr_In_Decl (R, Subt); |
| Set_Ekind (Def_Id, Kind); |
| |
| end Set_Scalar_Range_For_Subtype; |
| |
| -------------------------------------------------------- |
| -- Set_Stored_Constraint_From_Discriminant_Constraint -- |
| -------------------------------------------------------- |
| |
| procedure Set_Stored_Constraint_From_Discriminant_Constraint |
| (E : Entity_Id) |
| is |
| begin |
| -- Make sure set if encountered during Expand_To_Stored_Constraint |
| |
| Set_Stored_Constraint (E, No_Elist); |
| |
| -- Give it the right value |
| |
| if Is_Constrained (E) and then Has_Discriminants (E) then |
| Set_Stored_Constraint (E, |
| Expand_To_Stored_Constraint (E, Discriminant_Constraint (E))); |
| end if; |
| end Set_Stored_Constraint_From_Discriminant_Constraint; |
| |
| ------------------------------------- |
| -- Signed_Integer_Type_Declaration -- |
| ------------------------------------- |
| |
| procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is |
| Implicit_Base : Entity_Id; |
| Base_Typ : Entity_Id; |
| Lo_Val : Uint; |
| Hi_Val : Uint; |
| Errs : Boolean := False; |
| Lo : Node_Id; |
| Hi : Node_Id; |
| |
| function Can_Derive_From (E : Entity_Id) return Boolean; |
| -- Determine whether given bounds allow derivation from specified type |
| |
| procedure Check_Bound (Expr : Node_Id); |
| -- Check bound to make sure it is integral and static. If not, post |
| -- appropriate error message and set Errs flag |
| |
| --------------------- |
| -- Can_Derive_From -- |
| --------------------- |
| |
| -- Note we check both bounds against both end values, to deal with |
| -- strange types like ones with a range of 0 .. -12341234. |
| |
| function Can_Derive_From (E : Entity_Id) return Boolean is |
| Lo : constant Uint := Expr_Value (Type_Low_Bound (E)); |
| Hi : constant Uint := Expr_Value (Type_High_Bound (E)); |
| begin |
| return Lo <= Lo_Val and then Lo_Val <= Hi |
| and then |
| Lo <= Hi_Val and then Hi_Val <= Hi; |
| end Can_Derive_From; |
| |
| ----------------- |
| -- Check_Bound -- |
| ----------------- |
| |
| procedure Check_Bound (Expr : Node_Id) is |
| begin |
| -- If a range constraint is used as an integer type definition, each |
| -- bound of the range must be defined by a static expression of some |
| -- integer type, but the two bounds need not have the same integer |
| -- type (Negative bounds are allowed.) (RM 3.5.4) |
| |
| if not Is_Integer_Type (Etype (Expr)) then |
| Error_Msg_N |
| ("integer type definition bounds must be of integer type", Expr); |
| Errs := True; |
| |
| elsif not Is_OK_Static_Expression (Expr) then |
| Flag_Non_Static_Expr |
| ("non-static expression used for integer type bound!", Expr); |
| Errs := True; |
| |
| -- The bounds are folded into literals, and we set their type to be |
| -- universal, to avoid typing difficulties: we cannot set the type |
| -- of the literal to the new type, because this would be a forward |
| -- reference for the back end, and if the original type is user- |
| -- defined this can lead to spurious semantic errors (e.g. 2928-003). |
| |
| else |
| if Is_Entity_Name (Expr) then |
| Fold_Uint (Expr, Expr_Value (Expr), True); |
| end if; |
| |
| Set_Etype (Expr, Universal_Integer); |
| end if; |
| end Check_Bound; |
| |
| -- Start of processing for Signed_Integer_Type_Declaration |
| |
| begin |
| -- Create an anonymous base type |
| |
| Implicit_Base := |
| Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B'); |
| |
| -- Analyze and check the bounds, they can be of any integer type |
| |
| Lo := Low_Bound (Def); |
| Hi := High_Bound (Def); |
| |
| -- Arbitrarily use Integer as the type if either bound had an error |
| |
| if Hi = Error or else Lo = Error then |
| Base_Typ := Any_Integer; |
| Set_Error_Posted (T, True); |
| |
| -- Here both bounds are OK expressions |
| |
| else |
| Analyze_And_Resolve (Lo, Any_Integer); |
| Analyze_And_Resolve (Hi, Any_Integer); |
| |
| Check_Bound (Lo); |
| Check_Bound (Hi); |
| |
| if Errs then |
| Hi := Type_High_Bound (Standard_Long_Long_Integer); |
| Lo := Type_Low_Bound (Standard_Long_Long_Integer); |
| end if; |
| |
| -- Find type to derive from |
| |
| Lo_Val := Expr_Value (Lo); |
| Hi_Val := Expr_Value (Hi); |
| |
| if Can_Derive_From (Standard_Short_Short_Integer) then |
| Base_Typ := Base_Type (Standard_Short_Short_Integer); |
| |
| elsif Can_Derive_From (Standard_Short_Integer) then |
| Base_Typ := Base_Type (Standard_Short_Integer); |
| |
| elsif Can_Derive_From (Standard_Integer) then |
| Base_Typ := Base_Type (Standard_Integer); |
| |
| elsif Can_Derive_From (Standard_Long_Integer) then |
| Base_Typ := Base_Type (Standard_Long_Integer); |
| |
| elsif Can_Derive_From (Standard_Long_Long_Integer) then |
| Base_Typ := Base_Type (Standard_Long_Long_Integer); |
| |
| else |
| Base_Typ := Base_Type (Standard_Long_Long_Integer); |
| Error_Msg_N ("integer type definition bounds out of range", Def); |
| Hi := Type_High_Bound (Standard_Long_Long_Integer); |
| Lo := Type_Low_Bound (Standard_Long_Long_Integer); |
| end if; |
| end if; |
| |
| -- Complete both implicit base and declared first subtype entities |
| |
| Set_Etype (Implicit_Base, Base_Typ); |
| Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ)); |
| Set_Size_Info (Implicit_Base, (Base_Typ)); |
| Set_RM_Size (Implicit_Base, RM_Size (Base_Typ)); |
| Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ)); |
| |
| Set_Ekind (T, E_Signed_Integer_Subtype); |
| Set_Etype (T, Implicit_Base); |
| |
| Set_Size_Info (T, (Implicit_Base)); |
| Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base)); |
| Set_Scalar_Range (T, Def); |
| Set_RM_Size (T, UI_From_Int (Minimum_Size (T))); |
| Set_Is_Constrained (T); |
| end Signed_Integer_Type_Declaration; |
| |
| end Sem_Ch3; |