------------------------------------------------------------------------------
--                                                                          --
--                         GNAT COMPILER COMPONENTS                         --
--                                                                          --
--                              P R J . P R O C                             --
--                                                                          --
--                                 B o d y                                  --
--                                                                          --
--          Copyright (C) 2001-2005, 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 Err_Vars; use Err_Vars;
with Namet;    use Namet;
with Opt;
with Osint;    use Osint;
with Output;   use Output;
with Prj.Attr; use Prj.Attr;
with Prj.Err;  use Prj.Err;
with Prj.Ext;  use Prj.Ext;
with Prj.Nmsc; use Prj.Nmsc;
with Sinput;   use Sinput;
with Snames;

with GNAT.Case_Util; use GNAT.Case_Util;
with GNAT.HTable;

package body Prj.Proc is

   Error_Report : Put_Line_Access := null;

   package Processed_Projects is new GNAT.HTable.Simple_HTable
     (Header_Num => Header_Num,
      Element    => Project_Id,
      No_Element => No_Project,
      Key        => Name_Id,
      Hash       => Hash,
      Equal      => "=");
   --  This hash table contains all processed projects

   procedure Add (To_Exp : in out Name_Id; Str : Name_Id);
   --  Concatenate two strings and returns another string if both
   --  arguments are not null string.

   procedure Add_Attributes
     (Project : Project_Id;
      In_Tree : Project_Tree_Ref;
      Decl    : in out Declarations;
      First   : Attribute_Node_Id);
   --  Add all attributes, starting with First, with their default
   --  values to the package or project with declarations Decl.

   procedure Check
     (In_Tree         : Project_Tree_Ref;
      Project         : in out Project_Id;
      Follow_Links    : Boolean;
      When_No_Sources : Error_Warning);
   --  Set all projects to not checked, then call Recursive_Check for the
   --  main project Project. Project is set to No_Project if errors occurred.

   procedure Copy_Package_Declarations
     (From    : Declarations;
      To      : in out Declarations;
      New_Loc : Source_Ptr;
      In_Tree : Project_Tree_Ref);
   --  Copy a package declaration From to To for a renamed package. Change the
   --  locations of all the attributes to New_Loc.

   function Expression
     (Project                : Project_Id;
      In_Tree                : Project_Tree_Ref;
      From_Project_Node      : Project_Node_Id;
      From_Project_Node_Tree : Project_Node_Tree_Ref;
      Pkg                    : Package_Id;
      First_Term             : Project_Node_Id;
      Kind                   : Variable_Kind) return Variable_Value;
   --  From N_Expression project node From_Project_Node, compute the value
   --  of an expression and return it as a Variable_Value.

   function Imported_Or_Extended_Project_From
     (Project   : Project_Id;
      In_Tree   : Project_Tree_Ref;
      With_Name : Name_Id) return Project_Id;
   --  Find an imported or extended project of Project whose name is With_Name

   function Package_From
     (Project   : Project_Id;
      In_Tree   : Project_Tree_Ref;
      With_Name : Name_Id) return Package_Id;
   --  Find the package of Project whose name is With_Name

   procedure Process_Declarative_Items
     (Project                : Project_Id;
      In_Tree                : Project_Tree_Ref;
      From_Project_Node      : Project_Node_Id;
      From_Project_Node_Tree : Project_Node_Tree_Ref;
      Pkg                    : Package_Id;
      Item                   : Project_Node_Id);
   --  Process declarative items starting with From_Project_Node, and put them
   --  in declarations Decl. This is a recursive procedure; it calls itself for
   --  a package declaration or a case construction.

   procedure Recursive_Process
     (In_Tree                : Project_Tree_Ref;
      Project                : out Project_Id;
      From_Project_Node      : Project_Node_Id;
      From_Project_Node_Tree : Project_Node_Tree_Ref;
      Extended_By            : Project_Id);
   --  Process project with node From_Project_Node in the tree.
   --  Do nothing if From_Project_Node is Empty_Node.
   --  If project has already been processed, simply return its project id.
   --  Otherwise create a new project id, mark it as processed, call itself
   --  recursively for all imported projects and a extended project, if any.
   --  Then process the declarative items of the project.

   procedure Recursive_Check
     (Project         : Project_Id;
      In_Tree         : Project_Tree_Ref;
      Follow_Links    : Boolean;
      When_No_Sources : Error_Warning);
   --  If Project is not marked as checked, mark it as checked, call
   --  Check_Naming_Scheme for the project, then call itself for a
   --  possible extended project and all the imported projects of Project.

   ---------
   -- Add --
   ---------

   procedure Add (To_Exp : in out Name_Id; Str : Name_Id) is
   begin
      if To_Exp = Types.No_Name or else To_Exp = Empty_String then

         --  To_Exp is nil or empty. The result is Str

         To_Exp := Str;

      --  If Str is nil, then do not change To_Ext

      elsif Str /= No_Name and then Str /= Empty_String then
         declare
            S : constant String := Get_Name_String (Str);

         begin
            Get_Name_String (To_Exp);
            Add_Str_To_Name_Buffer (S);
            To_Exp := Name_Find;
         end;
      end if;
   end Add;

   --------------------
   -- Add_Attributes --
   --------------------

   procedure Add_Attributes
     (Project : Project_Id;
      In_Tree : Project_Tree_Ref;
      Decl    : in out Declarations;
      First   : Attribute_Node_Id)
   is
      The_Attribute  : Attribute_Node_Id := First;

   begin
      while The_Attribute /= Empty_Attribute loop
         if Attribute_Kind_Of (The_Attribute) = Single then
            declare
               New_Attribute : Variable_Value;

            begin
               case Variable_Kind_Of (The_Attribute) is

                  --  Undefined should not happen

                  when Undefined =>
                     pragma Assert
                       (False, "attribute with an undefined kind");
                     raise Program_Error;

                  --  Single attributes have a default value of empty string

                  when Single =>
                     New_Attribute :=
                       (Project  => Project,
                        Kind     => Single,
                        Location => No_Location,
                        Default  => True,
                        Value    => Empty_String,
                        Index    => 0);

                  --  List attributes have a default value of nil list

                  when List =>
                     New_Attribute :=
                       (Project  => Project,
                        Kind     => List,
                        Location => No_Location,
                        Default  => True,
                        Values   => Nil_String);

               end case;

               Variable_Element_Table.Increment_Last
                 (In_Tree.Variable_Elements);
               In_Tree.Variable_Elements.Table
                 (Variable_Element_Table.Last
                   (In_Tree.Variable_Elements)) :=
                 (Next  => Decl.Attributes,
                  Name  => Attribute_Name_Of (The_Attribute),
                  Value => New_Attribute);
               Decl.Attributes := Variable_Element_Table.Last
                 (In_Tree.Variable_Elements);
            end;
         end if;

         The_Attribute := Next_Attribute (After => The_Attribute);
      end loop;
   end Add_Attributes;

   -----------
   -- Check --
   -----------

   procedure Check
     (In_Tree         : Project_Tree_Ref;
      Project         : in out Project_Id;
      Follow_Links    : Boolean;
      When_No_Sources : Error_Warning)
   is
   begin
      --  Make sure that all projects are marked as not checked

      for Index in Project_Table.First ..
                   Project_Table.Last (In_Tree.Projects)
      loop
         In_Tree.Projects.Table (Index).Checked := False;
      end loop;

      Recursive_Check (Project, In_Tree, Follow_Links, When_No_Sources);
   end Check;

   -------------------------------
   -- Copy_Package_Declarations --
   -------------------------------

   procedure Copy_Package_Declarations
     (From    : Declarations;
      To      : in out Declarations;
      New_Loc : Source_Ptr;
      In_Tree : Project_Tree_Ref)
   is
      V1  : Variable_Id := From.Attributes;
      V2  : Variable_Id := No_Variable;
      Var : Variable;
      A1  : Array_Id := From.Arrays;
      A2  : Array_Id := No_Array;
      Arr : Array_Data;
      E1  : Array_Element_Id;
      E2  : Array_Element_Id := No_Array_Element;
      Elm : Array_Element;

   begin
      --  To avoid references in error messages to attribute declarations in
      --  an original package that has been renamed, copy all the attribute
      --  declarations of the package and change all locations to New_Loc,
      --  the location of the renamed package.

      --  First single attributes

      while V1 /= No_Variable loop

         --  Copy the attribute

         Var := In_Tree.Variable_Elements.Table (V1);
         V1  := Var.Next;

         --  Remove the Next component

         Var.Next := No_Variable;

         --  Change the location to New_Loc

         Var.Value.Location := New_Loc;
         Variable_Element_Table.Increment_Last (In_Tree.Variable_Elements);

         --  Put in new declaration

         if To.Attributes = No_Variable then
            To.Attributes :=
              Variable_Element_Table.Last (In_Tree.Variable_Elements);

         else
            In_Tree.Variable_Elements.Table (V2).Next :=
              Variable_Element_Table.Last (In_Tree.Variable_Elements);
         end if;

         V2 := Variable_Element_Table.Last (In_Tree.Variable_Elements);
         In_Tree.Variable_Elements.Table (V2) := Var;
      end loop;

      --  Then the associated array attributes

      while A1 /= No_Array loop

         --  Copy the array

         Arr := In_Tree.Arrays.Table (A1);
         A1  := Arr.Next;

         --  Remove the Next component

         Arr.Next := No_Array;

         Array_Table.Increment_Last (In_Tree.Arrays);

         --  Create new Array declaration
         if To.Arrays = No_Array then
            To.Arrays := Array_Table.Last (In_Tree.Arrays);

         else
            In_Tree.Arrays.Table (A2).Next :=
              Array_Table.Last (In_Tree.Arrays);
         end if;

         A2 := Array_Table.Last (In_Tree.Arrays);

         --  Don't store the array, as its first element has not been set yet

         --  Copy the array elements of the array

         E1 := Arr.Value;
         Arr.Value := No_Array_Element;

         while E1 /= No_Array_Element loop

            --  Copy the array element

            Elm := In_Tree.Array_Elements.Table (E1);
            E1 := Elm.Next;

            --  Remove the Next component

            Elm.Next := No_Array_Element;

            --  Change the location

            Elm.Value.Location := New_Loc;
            Array_Element_Table.Increment_Last (In_Tree.Array_Elements);

            --  Create new array element

            if Arr.Value = No_Array_Element then
               Arr.Value := Array_Element_Table.Last (In_Tree.Array_Elements);
            else
               In_Tree.Array_Elements.Table (E2).Next :=
                 Array_Element_Table.Last (In_Tree.Array_Elements);
            end if;

            E2 := Array_Element_Table.Last (In_Tree.Array_Elements);
            In_Tree.Array_Elements.Table (E2) := Elm;
         end loop;

         --  Finally, store the new array

         In_Tree.Arrays.Table (A2) := Arr;
      end loop;
   end Copy_Package_Declarations;

   ----------------
   -- Expression --
   ----------------

   function Expression
     (Project                : Project_Id;
      In_Tree                : Project_Tree_Ref;
      From_Project_Node      : Project_Node_Id;
      From_Project_Node_Tree : Project_Node_Tree_Ref;
      Pkg                    : Package_Id;
      First_Term             : Project_Node_Id;
      Kind                   : Variable_Kind) return Variable_Value
   is
      The_Term : Project_Node_Id := First_Term;
      --  The term in the expression list

      The_Current_Term : Project_Node_Id := Empty_Node;
      --  The current term node id

      Result : Variable_Value (Kind => Kind);
      --  The returned result

      Last : String_List_Id := Nil_String;
      --  Reference to the last string elements in Result, when Kind is List

   begin
      Result.Project := Project;
      Result.Location := Location_Of (First_Term, From_Project_Node_Tree);

      --  Process each term of the expression, starting with First_Term

      while The_Term /= Empty_Node loop
         The_Current_Term := Current_Term (The_Term, From_Project_Node_Tree);

         case Kind_Of (The_Current_Term, From_Project_Node_Tree) is

            when N_Literal_String =>

               case Kind is

                  when Undefined =>

                     --  Should never happen

                     pragma Assert (False, "Undefined expression kind");
                     raise Program_Error;

                  when Single =>
                     Add (Result.Value,
                          String_Value_Of
                            (The_Current_Term, From_Project_Node_Tree));
                     Result.Index :=
                       Source_Index_Of
                         (The_Current_Term, From_Project_Node_Tree);

                  when List =>

                     String_Element_Table.Increment_Last
                       (In_Tree.String_Elements);

                     if Last = Nil_String then

                        --  This can happen in an expression like () & "toto"

                        Result.Values := String_Element_Table.Last
                          (In_Tree.String_Elements);

                     else
                        In_Tree.String_Elements.Table
                          (Last).Next := String_Element_Table.Last
                                       (In_Tree.String_Elements);
                     end if;

                     Last := String_Element_Table.Last
                       (In_Tree.String_Elements);
                     In_Tree.String_Elements.Table (Last) :=
                       (Value    =>
                          String_Value_Of
                            (The_Current_Term,
                             From_Project_Node_Tree),
                        Index    =>
                          Source_Index_Of
                            (The_Current_Term, From_Project_Node_Tree),
                        Display_Value => No_Name,
                        Location      =>
                          Location_Of
                            (The_Current_Term,
                             From_Project_Node_Tree),
                        Flag     => False,
                        Next     => Nil_String);
               end case;

            when N_Literal_String_List =>

               declare
                  String_Node : Project_Node_Id :=
                                  First_Expression_In_List
                                    (The_Current_Term,
                                     From_Project_Node_Tree);

                  Value : Variable_Value;

               begin
                  if String_Node /= Empty_Node then

                     --  If String_Node is nil, it is an empty list,
                     --  there is nothing to do

                     Value := Expression
                       (Project                => Project,
                        In_Tree                => In_Tree,
                        From_Project_Node      => From_Project_Node,
                        From_Project_Node_Tree => From_Project_Node_Tree,
                        Pkg                    => Pkg,
                        First_Term             =>
                          Tree.First_Term
                            (String_Node, From_Project_Node_Tree),
                        Kind                   => Single);
                     String_Element_Table.Increment_Last
                       (In_Tree.String_Elements);

                     if Result.Values = Nil_String then

                        --  This literal string list is the first term
                        --  in a string list expression

                        Result.Values :=
                          String_Element_Table.Last (In_Tree.String_Elements);

                     else
                        In_Tree.String_Elements.Table
                          (Last).Next :=
                          String_Element_Table.Last (In_Tree.String_Elements);
                     end if;

                     Last :=
                       String_Element_Table.Last (In_Tree.String_Elements);

                     In_Tree.String_Elements.Table (Last) :=
                       (Value    => Value.Value,
                        Display_Value => No_Name,
                        Location => Value.Location,
                        Flag     => False,
                        Next     => Nil_String,
                        Index    => Value.Index);

                     loop
                        --  Add the other element of the literal string list
                        --  one after the other

                        String_Node :=
                          Next_Expression_In_List
                            (String_Node, From_Project_Node_Tree);

                        exit when String_Node = Empty_Node;

                        Value :=
                          Expression
                            (Project                => Project,
                             In_Tree                => In_Tree,
                             From_Project_Node      => From_Project_Node,
                             From_Project_Node_Tree => From_Project_Node_Tree,
                             Pkg                    => Pkg,
                             First_Term             =>
                               Tree.First_Term
                                 (String_Node, From_Project_Node_Tree),
                             Kind                   => Single);

                        String_Element_Table.Increment_Last
                          (In_Tree.String_Elements);
                        In_Tree.String_Elements.Table
                          (Last).Next := String_Element_Table.Last
                                        (In_Tree.String_Elements);
                        Last := String_Element_Table.Last
                          (In_Tree.String_Elements);
                        In_Tree.String_Elements.Table (Last) :=
                          (Value    => Value.Value,
                           Display_Value => No_Name,
                           Location => Value.Location,
                           Flag     => False,
                           Next     => Nil_String,
                           Index    => Value.Index);
                     end loop;
                  end if;
               end;

            when N_Variable_Reference | N_Attribute_Reference =>

               declare
                  The_Project     : Project_Id  := Project;
                  The_Package     : Package_Id  := Pkg;
                  The_Name        : Name_Id     := No_Name;
                  The_Variable_Id : Variable_Id := No_Variable;
                  The_Variable    : Variable_Value;
                  Term_Project    : constant Project_Node_Id :=
                    Project_Node_Of
                      (The_Current_Term, From_Project_Node_Tree);
                  Term_Package    : constant Project_Node_Id :=
                    Package_Node_Of
                      (The_Current_Term, From_Project_Node_Tree);
                  Index           : Name_Id   := No_Name;

               begin
                  if Term_Project /= Empty_Node and then
                     Term_Project /= From_Project_Node
                  then
                     --  This variable or attribute comes from another project

                     The_Name :=
                       Name_Of (Term_Project, From_Project_Node_Tree);
                     The_Project := Imported_Or_Extended_Project_From
                                      (Project   => Project,
                                       In_Tree   => In_Tree,
                                       With_Name => The_Name);
                  end if;

                  if Term_Package /= Empty_Node then

                     --  This is an attribute of a package

                     The_Name :=
                       Name_Of (Term_Package, From_Project_Node_Tree);
                     The_Package := In_Tree.Projects.Table
                                      (The_Project).Decl.Packages;

                     while The_Package /= No_Package
                       and then In_Tree.Packages.Table
                                  (The_Package).Name /= The_Name
                     loop
                        The_Package :=
                          In_Tree.Packages.Table
                            (The_Package).Next;
                     end loop;

                     pragma Assert
                       (The_Package /= No_Package,
                        "package not found.");

                  elsif Kind_Of (The_Current_Term, From_Project_Node_Tree) =
                          N_Attribute_Reference
                  then
                     The_Package := No_Package;
                  end if;

                  The_Name :=
                    Name_Of (The_Current_Term, From_Project_Node_Tree);

                  if Kind_Of (The_Current_Term, From_Project_Node_Tree) =
                       N_Attribute_Reference
                  then
                     Index :=
                       Associative_Array_Index_Of
                         (The_Current_Term, From_Project_Node_Tree);
                  end if;

                  --  If it is not an associative array attribute

                  if Index = No_Name then

                     --  It is not an associative array attribute

                     if The_Package /= No_Package then

                        --  First, if there is a package, look into the package

                        if Kind_Of (The_Current_Term, From_Project_Node_Tree) =
                             N_Variable_Reference
                        then
                           The_Variable_Id :=
                             In_Tree.Packages.Table
                               (The_Package).Decl.Variables;
                        else
                           The_Variable_Id :=
                             In_Tree.Packages.Table
                               (The_Package).Decl.Attributes;
                        end if;

                        while The_Variable_Id /= No_Variable
                          and then
                            In_Tree.Variable_Elements.Table
                              (The_Variable_Id).Name /= The_Name
                        loop
                           The_Variable_Id :=
                             In_Tree.Variable_Elements.Table
                               (The_Variable_Id).Next;
                        end loop;

                     end if;

                     if The_Variable_Id = No_Variable then

                        --  If we have not found it, look into the project

                        if Kind_Of (The_Current_Term, From_Project_Node_Tree) =
                             N_Variable_Reference
                        then
                           The_Variable_Id :=
                             In_Tree.Projects.Table
                               (The_Project).Decl.Variables;
                        else
                           The_Variable_Id :=
                             In_Tree.Projects.Table
                               (The_Project).Decl.Attributes;
                        end if;

                        while The_Variable_Id /= No_Variable
                          and then
                          In_Tree.Variable_Elements.Table
                            (The_Variable_Id).Name /= The_Name
                        loop
                           The_Variable_Id :=
                             In_Tree.Variable_Elements.Table
                               (The_Variable_Id).Next;
                        end loop;

                     end if;

                     pragma Assert (The_Variable_Id /= No_Variable,
                                      "variable or attribute not found");

                     The_Variable :=
                       In_Tree.Variable_Elements.Table
                                                    (The_Variable_Id).Value;

                  else

                     --  It is an associative array attribute

                     declare
                        The_Array   : Array_Id := No_Array;
                        The_Element : Array_Element_Id := No_Array_Element;
                        Array_Index : Name_Id := No_Name;

                     begin
                        if The_Package /= No_Package then
                           The_Array :=
                             In_Tree.Packages.Table
                               (The_Package).Decl.Arrays;
                        else
                           The_Array :=
                             In_Tree.Projects.Table
                               (The_Project).Decl.Arrays;
                        end if;

                        while The_Array /= No_Array
                          and then In_Tree.Arrays.Table
                                     (The_Array).Name /= The_Name
                        loop
                           The_Array := In_Tree.Arrays.Table
                                          (The_Array).Next;
                        end loop;

                        if The_Array /= No_Array then
                           The_Element := In_Tree.Arrays.Table
                                            (The_Array).Value;

                           Get_Name_String (Index);

                           if Case_Insensitive
                                (The_Current_Term, From_Project_Node_Tree)
                           then
                              To_Lower (Name_Buffer (1 .. Name_Len));
                           end if;

                           Array_Index := Name_Find;

                           while The_Element /= No_Array_Element
                             and then
                             In_Tree.Array_Elements.Table
                               (The_Element).Index /= Array_Index
                           loop
                              The_Element :=
                                In_Tree.Array_Elements.Table
                                  (The_Element).Next;
                           end loop;

                        end if;

                        if The_Element /= No_Array_Element then
                           The_Variable :=
                             In_Tree.Array_Elements.Table
                               (The_Element).Value;

                        else
                           if Expression_Kind_Of
                             (The_Current_Term, From_Project_Node_Tree) =
                                                                        List
                           then
                              The_Variable :=
                                (Project  => Project,
                                 Kind     => List,
                                 Location => No_Location,
                                 Default  => True,
                                 Values   => Nil_String);
                           else
                              The_Variable :=
                                (Project  => Project,
                                 Kind     => Single,
                                 Location => No_Location,
                                 Default  => True,
                                 Value    => Empty_String,
                                 Index    => 0);
                           end if;
                        end if;
                     end;
                  end if;

                  case Kind is

                     when Undefined =>

                        --  Should never happen

                        pragma Assert (False, "undefined expression kind");
                        null;

                     when Single =>

                        case The_Variable.Kind is

                           when Undefined =>
                              null;

                           when Single =>
                              Add (Result.Value, The_Variable.Value);

                           when List =>

                              --  Should never happen

                              pragma Assert
                                (False,
                                 "list cannot appear in single " &
                                 "string expression");
                              null;
                        end case;

                     when List =>
                        case The_Variable.Kind is

                           when Undefined =>
                              null;

                           when Single =>
                              String_Element_Table.Increment_Last
                                (In_Tree.String_Elements);

                              if Last = Nil_String then

                                 --  This can happen in an expression such as
                                 --  () & Var

                                 Result.Values :=
                                   String_Element_Table.Last
                                     (In_Tree.String_Elements);

                              else
                                 In_Tree.String_Elements.Table
                                   (Last).Next :=
                                     String_Element_Table.Last
                                       (In_Tree.String_Elements);
                              end if;

                              Last :=
                                String_Element_Table.Last
                                  (In_Tree.String_Elements);

                              In_Tree.String_Elements.Table (Last) :=
                                (Value         => The_Variable.Value,
                                 Display_Value => No_Name,
                                 Location      => Location_Of
                                                    (The_Current_Term,
                                                     From_Project_Node_Tree),
                                 Flag          => False,
                                 Next          => Nil_String,
                                 Index         => 0);

                           when List =>

                              declare
                                 The_List : String_List_Id :=
                                              The_Variable.Values;

                              begin
                                 while The_List /= Nil_String loop
                                    String_Element_Table.Increment_Last
                                      (In_Tree.String_Elements);

                                    if Last = Nil_String then
                                       Result.Values :=
                                         String_Element_Table.Last
                                           (In_Tree.
                                                String_Elements);

                                    else
                                       In_Tree.
                                         String_Elements.Table (Last).Next :=
                                         String_Element_Table.Last
                                           (In_Tree.
                                                String_Elements);

                                    end if;

                                    Last :=
                                      String_Element_Table.Last
                                        (In_Tree.String_Elements);

                                    In_Tree.String_Elements.Table (Last) :=
                                      (Value         =>
                                         In_Tree.String_Elements.Table
                                           (The_List).Value,
                                       Display_Value => No_Name,
                                       Location      =>
                                         Location_Of
                                           (The_Current_Term,
                                            From_Project_Node_Tree),
                                       Flag         => False,
                                       Next         => Nil_String,
                                       Index        => 0);

                                    The_List :=
                                      In_Tree. String_Elements.Table
                                        (The_List).Next;
                                 end loop;
                              end;
                        end case;
                  end case;
               end;

            when N_External_Value =>
               Get_Name_String
                 (String_Value_Of
                    (External_Reference_Of
                       (The_Current_Term, From_Project_Node_Tree),
                     From_Project_Node_Tree));

               declare
                  Name    : constant Name_Id  := Name_Find;
                  Default : Name_Id           := No_Name;
                  Value   : Name_Id           := No_Name;

                  Def_Var : Variable_Value;

                  Default_Node : constant Project_Node_Id :=
                    External_Default_Of
                      (The_Current_Term, From_Project_Node_Tree);

               begin
                  --  If there is a default value for the external reference,
                  --  get its value.

                  if Default_Node /= Empty_Node then
                     Def_Var := Expression
                       (Project                => Project,
                        In_Tree                => In_Tree,
                        From_Project_Node      => Default_Node,
                        From_Project_Node_Tree => From_Project_Node_Tree,
                        Pkg                    => Pkg,
                        First_Term             =>
                          Tree.First_Term
                            (Default_Node, From_Project_Node_Tree),
                        Kind                   => Single);

                     if Def_Var /= Nil_Variable_Value then
                        Default := Def_Var.Value;
                     end if;
                  end if;

                  Value := Prj.Ext.Value_Of (Name, Default);

                  if Value = No_Name then
                     if not Opt.Quiet_Output then
                        if Error_Report = null then
                           Error_Msg
                             ("?undefined external reference",
                              Location_Of
                                (The_Current_Term, From_Project_Node_Tree));
                        else
                           Error_Report
                             ("warning: """ & Get_Name_String (Name) &
                              """ is an undefined external reference",
                              Project, In_Tree);
                        end if;
                     end if;

                     Value := Empty_String;
                  end if;

                  case Kind is

                     when Undefined =>
                        null;

                     when Single =>
                        Add (Result.Value, Value);

                     when List =>
                        String_Element_Table.Increment_Last
                          (In_Tree.String_Elements);

                        if Last = Nil_String then
                           Result.Values := String_Element_Table.Last
                             (In_Tree.String_Elements);

                        else
                           In_Tree.String_Elements.Table
                             (Last).Next := String_Element_Table.Last
                                       (In_Tree.String_Elements);
                        end if;

                        Last := String_Element_Table.Last
                                  (In_Tree.String_Elements);
                        In_Tree.String_Elements.Table (Last) :=
                          (Value    => Value,
                           Display_Value => No_Name,
                           Location      =>
                             Location_Of
                               (The_Current_Term, From_Project_Node_Tree),
                           Flag     => False,
                           Next     => Nil_String,
                           Index    => 0);

                  end case;
               end;

            when others =>

               --  Should never happen

               pragma Assert
                 (False,
                  "illegal node kind in an expression");
               raise Program_Error;

         end case;

         The_Term := Next_Term (The_Term, From_Project_Node_Tree);
      end loop;

      return Result;
   end Expression;

   ---------------------------------------
   -- Imported_Or_Extended_Project_From --
   ---------------------------------------

   function Imported_Or_Extended_Project_From
     (Project   : Project_Id;
      In_Tree   : Project_Tree_Ref;
      With_Name : Name_Id) return Project_Id
   is
      Data        : constant Project_Data :=
                      In_Tree.Projects.Table (Project);
      List        : Project_List          := Data.Imported_Projects;
      Result      : Project_Id := No_Project;
      Temp_Result : Project_Id := No_Project;

   begin
      --  First check if it is the name of an extended project

      if Data.Extends /= No_Project
        and then In_Tree.Projects.Table (Data.Extends).Name =
                   With_Name
      then
         return Data.Extends;

      else
         --  Then check the name of each imported project

         while List /= Empty_Project_List loop
            Result := In_Tree.Project_Lists.Table (List).Project;

            --  If the project is directly imported, then returns its ID

            if
              In_Tree.Projects.Table (Result).Name = With_Name
            then
               return Result;
            end if;

            --  If a project extending the project is imported, then keep
            --  this extending project as a possibility. It will be the
            --  returned ID if the project is not imported directly.

            declare
               Proj : Project_Id :=
                 In_Tree.Projects.Table (Result).Extends;
            begin
               while Proj /= No_Project loop
                  if In_Tree.Projects.Table (Proj).Name =
                       With_Name
                  then
                     Temp_Result := Result;
                     exit;
                  end if;

                  Proj := In_Tree.Projects.Table (Proj).Extends;
               end loop;
            end;

            List := In_Tree.Project_Lists.Table (List).Next;
         end loop;

         pragma Assert
           (Temp_Result /= No_Project,
           "project not found");

         return Temp_Result;
      end if;
   end Imported_Or_Extended_Project_From;

   ------------------
   -- Package_From --
   ------------------

   function Package_From
     (Project   : Project_Id;
      In_Tree   : Project_Tree_Ref;
      With_Name : Name_Id) return Package_Id
   is
      Data   : constant Project_Data :=
        In_Tree.Projects.Table (Project);
      Result : Package_Id := Data.Decl.Packages;

   begin
      --  Check the name of each existing package of Project

      while Result /= No_Package
        and then In_Tree.Packages.Table (Result).Name /= With_Name
      loop
         Result := In_Tree.Packages.Table (Result).Next;
      end loop;

      if Result = No_Package then

         --  Should never happen

         Write_Line ("package """ & Get_Name_String (With_Name) &
                     """ not found");
         raise Program_Error;

      else
         return Result;
      end if;
   end Package_From;

   -------------
   -- Process --
   -------------

   procedure Process
     (In_Tree                : Project_Tree_Ref;
      Project                : out Project_Id;
      Success                : out Boolean;
      From_Project_Node      : Project_Node_Id;
      From_Project_Node_Tree : Project_Node_Tree_Ref;
      Report_Error           : Put_Line_Access;
      Follow_Links           : Boolean := True;
      When_No_Sources        : Error_Warning := Error)
   is
      Obj_Dir    : Name_Id;
      Extending  : Project_Id;
      Extending2 : Project_Id;

   begin
      Error_Report := Report_Error;
      Success := True;

      --  Make sure there is no projects in the data structure

      Project_Table.Set_Last (In_Tree.Projects, No_Project);
      Processed_Projects.Reset;

      --  And process the main project and all of the projects it depends on,
      --  recursively

      Recursive_Process
        (Project                => Project,
         In_Tree                => In_Tree,
         From_Project_Node      => From_Project_Node,
         From_Project_Node_Tree => From_Project_Node_Tree,
         Extended_By            => No_Project);

      if Project /= No_Project then
         Check (In_Tree, Project, Follow_Links, When_No_Sources);
      end if;

      --  If main project is an extending all project, set the object
      --  directory of all virtual extending projects to the object directory
      --  of the main project.

      if Project /= No_Project
        and then Is_Extending_All (From_Project_Node, From_Project_Node_Tree)
      then
         declare
            Object_Dir : constant Name_Id :=
                           In_Tree.Projects.Table (Project).Object_Directory;
         begin
            for Index in
              Project_Table.First .. Project_Table.Last (In_Tree.Projects)
            loop
               if In_Tree.Projects.Table (Index).Virtual then
                  In_Tree.Projects.Table (Index).Object_Directory :=
                    Object_Dir;
               end if;
            end loop;
         end;
      end if;

      --  Check that no extending project shares its object directory with
      --  the project(s) it extends.

      if Project /= No_Project then
         for Proj in
           Project_Table.First .. Project_Table.Last (In_Tree.Projects)
         loop
            Extending := In_Tree.Projects.Table (Proj).Extended_By;

            if Extending /= No_Project then
               Obj_Dir := In_Tree.Projects.Table (Proj).Object_Directory;

               --  Check that a project being extended does not share its
               --  object directory with any project that extends it, directly
               --  or indirectly, including a virtual extending project.

               --  Start with the project directly extending it

               Extending2 := Extending;
               while Extending2 /= No_Project loop
                  if In_Tree.Projects.Table (Extending2).Ada_Sources_Present
                    and then
                      In_Tree.Projects.Table (Extending2).Object_Directory =
                                                                      Obj_Dir
                  then
                     if In_Tree.Projects.Table (Extending2).Virtual then
                        Error_Msg_Name_1 :=
                          In_Tree.Projects.Table (Proj).Display_Name;

                        if Error_Report = null then
                           Error_Msg
                             ("project { cannot be extended by a virtual " &
                              "project with the same object directory",
                              In_Tree.Projects.Table (Proj).Location);
                        else
                           Error_Report
                             ("project """ &
                              Get_Name_String (Error_Msg_Name_1) &
                              """ cannot be extended by a virtual " &
                              "project with the same object directory",
                              Project, In_Tree);
                        end if;

                     else
                        Error_Msg_Name_1 :=
                          In_Tree.Projects.Table (Extending2).Display_Name;
                        Error_Msg_Name_2 :=
                          In_Tree.Projects.Table (Proj).Display_Name;

                        if Error_Report = null then
                           Error_Msg
                             ("project { cannot extend project {",
                              In_Tree.Projects.Table (Extending2).Location);
                           Error_Msg
                             ("\they share the same object directory",
                              In_Tree.Projects.Table (Extending2).Location);

                        else
                           Error_Report
                             ("project """ &
                              Get_Name_String (Error_Msg_Name_1) &
                              """ cannot extend project """ &
                              Get_Name_String (Error_Msg_Name_2) & """",
                              Project, In_Tree);
                           Error_Report
                             ("they share the same object directory",
                              Project, In_Tree);
                        end if;
                     end if;
                  end if;

                  --  Continue with the next extending project, if any

                  Extending2 :=
                    In_Tree.Projects.Table (Extending2).Extended_By;
               end loop;
            end if;
         end loop;
      end if;

      Success := Total_Errors_Detected = 0;
   end Process;

   -------------------------------
   -- Process_Declarative_Items --
   -------------------------------

   procedure Process_Declarative_Items
     (Project                : Project_Id;
      In_Tree                : Project_Tree_Ref;
      From_Project_Node      : Project_Node_Id;
      From_Project_Node_Tree : Project_Node_Tree_Ref;
      Pkg                    : Package_Id;
      Item                   : Project_Node_Id)
   is
      Current_Declarative_Item : Project_Node_Id := Item;
      Current_Item             : Project_Node_Id := Empty_Node;

   begin
      --  For each declarative item

      while Current_Declarative_Item /= Empty_Node loop

         --  Get its data

         Current_Item :=
           Current_Item_Node
             (Current_Declarative_Item, From_Project_Node_Tree);

         --  And set Current_Declarative_Item to the next declarative item
         --  ready for the next iteration.

         Current_Declarative_Item :=
           Next_Declarative_Item
             (Current_Declarative_Item, From_Project_Node_Tree);

         case Kind_Of (Current_Item, From_Project_Node_Tree) is

            when N_Package_Declaration =>
               --  Do not process a package declaration that should be ignored

               if Expression_Kind_Of
                    (Current_Item, From_Project_Node_Tree) /= Ignored
               then
                  --  Create the new package

                  Package_Table.Increment_Last (In_Tree.Packages);

                  declare
                     New_Pkg         : constant Package_Id :=
                                         Package_Table.Last (In_Tree.Packages);
                     The_New_Package : Package_Element;

                     Project_Of_Renamed_Package :
                       constant Project_Node_Id :=
                         Project_Of_Renamed_Package_Of
                           (Current_Item, From_Project_Node_Tree);

                  begin
                     --  Set the name of the new package

                     The_New_Package.Name :=
                       Name_Of (Current_Item, From_Project_Node_Tree);

                     --  Insert the new package in the appropriate list

                     if Pkg /= No_Package then
                        The_New_Package.Next :=
                          In_Tree.Packages.Table (Pkg).Decl.Packages;
                        In_Tree.Packages.Table (Pkg).Decl.Packages :=
                          New_Pkg;
                     else
                        The_New_Package.Next :=
                          In_Tree.Projects.Table (Project).Decl.Packages;
                        In_Tree.Projects.Table (Project).Decl.Packages :=
                          New_Pkg;
                     end if;

                     In_Tree.Packages.Table (New_Pkg) :=
                       The_New_Package;

                     if Project_Of_Renamed_Package /= Empty_Node then

                        --  Renamed package

                        declare
                           Project_Name : constant Name_Id :=
                                            Name_Of
                                              (Project_Of_Renamed_Package,
                                               From_Project_Node_Tree);

                           Renamed_Project :
                             constant Project_Id :=
                               Imported_Or_Extended_Project_From
                               (Project, In_Tree, Project_Name);

                           Renamed_Package : constant Package_Id :=
                                               Package_From
                                                 (Renamed_Project, In_Tree,
                                                  Name_Of
                                                    (Current_Item,
                                                     From_Project_Node_Tree));

                        begin
                           --  For a renamed package, copy the declarations of
                           --  the renamed package, but set all the locations
                           --  to the location of the package name in the
                           --  renaming declaration.

                           Copy_Package_Declarations
                             (From     =>
                                In_Tree.Packages.Table (Renamed_Package).Decl,
                              To      =>
                                In_Tree.Packages.Table (New_Pkg).Decl,
                              New_Loc =>
                                Location_Of
                                  (Current_Item, From_Project_Node_Tree),
                              In_Tree => In_Tree);
                        end;

                     --  Standard package declaration, not renaming

                     else
                        --  Set the default values of the attributes

                        Add_Attributes
                          (Project, In_Tree,
                           In_Tree.Packages.Table (New_Pkg).Decl,
                           First_Attribute_Of
                             (Package_Id_Of
                                (Current_Item, From_Project_Node_Tree)));

                        --  And process declarative items of the new package

                        Process_Declarative_Items
                          (Project                => Project,
                           In_Tree                => In_Tree,
                           From_Project_Node      => From_Project_Node,
                           From_Project_Node_Tree => From_Project_Node_Tree,
                           Pkg                    => New_Pkg,
                           Item                   =>
                             First_Declarative_Item_Of
                               (Current_Item, From_Project_Node_Tree));
                     end if;
                  end;
               end if;

            when N_String_Type_Declaration =>

               --  There is nothing to process

               null;

            when N_Attribute_Declaration      |
                 N_Typed_Variable_Declaration |
                 N_Variable_Declaration       =>

               if Expression_Of (Current_Item, From_Project_Node_Tree) =
                    Empty_Node
               then

                  --  It must be a full associative array attribute declaration

                  declare
                     Current_Item_Name : constant Name_Id :=
                       Name_Of (Current_Item, From_Project_Node_Tree);
                     --  The name of the attribute

                     New_Array  : Array_Id;
                     --  The new associative array created

                     Orig_Array : Array_Id;
                     --  The associative array value

                     Orig_Project_Name : Name_Id := No_Name;
                     --  The name of the project where the associative array
                     --  value is.

                     Orig_Project : Project_Id := No_Project;
                     --  The id of the project where the associative array
                     --  value is.

                     Orig_Package_Name : Name_Id := No_Name;
                     --  The name of the package, if any, where the associative
                     --  array value is.

                     Orig_Package : Package_Id := No_Package;
                     --  The id of the package, if any, where the associative
                     --  array value is.

                     New_Element : Array_Element_Id := No_Array_Element;
                     --  Id of a new array element created

                     Prev_Element : Array_Element_Id := No_Array_Element;
                     --  Last new element id created

                     Orig_Element : Array_Element_Id := No_Array_Element;
                     --  Current array element in the original associative
                     --  array.

                     Next_Element : Array_Element_Id := No_Array_Element;
                     --  Id of the array element that follows the new element.
                     --  This is not always nil, because values for the
                     --  associative array attribute may already have been
                     --  declared, and the array elements declared are reused.

                  begin
                     --  First, find if the associative array attribute already
                     --  has elements declared.

                     if Pkg /= No_Package then
                        New_Array := In_Tree.Packages.Table
                                       (Pkg).Decl.Arrays;

                     else
                        New_Array := In_Tree.Projects.Table
                                       (Project).Decl.Arrays;
                     end if;

                     while New_Array /= No_Array
                       and then In_Tree.Arrays.Table (New_Array).Name /=
                                                           Current_Item_Name
                     loop
                        New_Array := In_Tree.Arrays.Table (New_Array).Next;
                     end loop;

                     --  If the attribute has never been declared add new entry
                     --  in the arrays of the project/package and link it.

                     if New_Array = No_Array then
                        Array_Table.Increment_Last (In_Tree.Arrays);
                        New_Array := Array_Table.Last (In_Tree.Arrays);

                        if Pkg /= No_Package then
                           In_Tree.Arrays.Table (New_Array) :=
                             (Name  => Current_Item_Name,
                              Value => No_Array_Element,
                              Next  =>
                                In_Tree.Packages.Table (Pkg).Decl.Arrays);

                           In_Tree.Packages.Table (Pkg).Decl.Arrays :=
                             New_Array;

                        else
                           In_Tree.Arrays.Table (New_Array) :=
                             (Name  => Current_Item_Name,
                              Value => No_Array_Element,
                              Next  =>
                                In_Tree.Projects.Table (Project).Decl.Arrays);

                           In_Tree.Projects.Table (Project).Decl.Arrays :=
                             New_Array;
                        end if;
                     end if;

                     --  Find the project where the value is declared

                     Orig_Project_Name :=
                       Name_Of
                         (Associative_Project_Of
                              (Current_Item, From_Project_Node_Tree),
                          From_Project_Node_Tree);

                     for Index in Project_Table.First ..
                                  Project_Table.Last
                                    (In_Tree.Projects)
                     loop
                        if In_Tree.Projects.Table (Index).Name =
                                                           Orig_Project_Name
                        then
                           Orig_Project := Index;
                           exit;
                        end if;
                     end loop;

                     pragma Assert (Orig_Project /= No_Project,
                                    "original project not found");

                     if Associative_Package_Of
                          (Current_Item, From_Project_Node_Tree) = Empty_Node
                     then
                        Orig_Array :=
                          In_Tree.Projects.Table
                            (Orig_Project).Decl.Arrays;

                     else
                        --  If in a package, find the package where the
                        --  value is declared.

                        Orig_Package_Name :=
                          Name_Of
                            (Associative_Package_Of
                                 (Current_Item, From_Project_Node_Tree),
                             From_Project_Node_Tree);

                        Orig_Package :=
                          In_Tree.Projects.Table
                            (Orig_Project).Decl.Packages;
                        pragma Assert (Orig_Package /= No_Package,
                                       "original package not found");

                        while In_Tree.Packages.Table
                                (Orig_Package).Name /= Orig_Package_Name
                        loop
                           Orig_Package := In_Tree.Packages.Table
                                             (Orig_Package).Next;
                           pragma Assert (Orig_Package /= No_Package,
                                          "original package not found");
                        end loop;

                        Orig_Array :=
                          In_Tree.Packages.Table
                            (Orig_Package).Decl.Arrays;
                     end if;

                     --  Now look for the array

                     while Orig_Array /= No_Array and then
                     In_Tree.Arrays.Table (Orig_Array).Name /=
                                                         Current_Item_Name
                     loop
                        Orig_Array := In_Tree.Arrays.Table
                                        (Orig_Array).Next;
                     end loop;

                     if Orig_Array = No_Array then
                        if Error_Report = null then
                           Error_Msg
                             ("associative array value cannot be found",
                              Location_Of
                                (Current_Item, From_Project_Node_Tree));

                        else
                           Error_Report
                             ("associative array value cannot be found",
                              Project, In_Tree);
                        end if;

                     else
                        Orig_Element :=
                          In_Tree.Arrays.Table (Orig_Array).Value;

                        --  Copy each array element

                        while Orig_Element /= No_Array_Element loop

                           --  Case of first element

                           if Prev_Element = No_Array_Element then

                              --  And there is no array element declared yet,
                              --  create a new first array element.

                              if In_Tree.Arrays.Table (New_Array).Value =
                                                              No_Array_Element
                              then
                                 Array_Element_Table.Increment_Last
                                   (In_Tree.Array_Elements);
                                 New_Element := Array_Element_Table.Last
                                   (In_Tree.Array_Elements);
                                 In_Tree.Arrays.Table
                                   (New_Array).Value := New_Element;
                                 Next_Element := No_Array_Element;

                              --  Otherwise, the new element is the first

                              else
                                 New_Element := In_Tree.Arrays.
                                                  Table (New_Array).Value;
                                 Next_Element :=
                                   In_Tree.Array_Elements.Table
                                     (New_Element).Next;
                              end if;

                           --  Otherwise, reuse an existing element, or create
                           --  one if necessary.

                           else
                              Next_Element :=
                                In_Tree.Array_Elements.Table
                                  (Prev_Element).Next;

                              if Next_Element = No_Array_Element then
                                 Array_Element_Table.Increment_Last
                                   (In_Tree.Array_Elements);
                                 New_Element := Array_Element_Table.Last
                                   (In_Tree.Array_Elements);

                              else
                                 New_Element := Next_Element;
                                 Next_Element :=
                                   In_Tree.Array_Elements.Table
                                     (New_Element).Next;
                              end if;
                           end if;

                           --  Copy the value of the element

                           In_Tree.Array_Elements.Table
                             (New_Element) :=
                               In_Tree.Array_Elements.Table
                                 (Orig_Element);
                           In_Tree.Array_Elements.Table
                             (New_Element).Value.Project := Project;

                           --  Adjust the Next link

                           In_Tree.Array_Elements.Table
                             (New_Element).Next := Next_Element;

                           --  Adjust the previous id for the next element

                           Prev_Element := New_Element;

                           --  Go to the next element in the original array

                           Orig_Element :=
                             In_Tree.Array_Elements.Table
                               (Orig_Element).Next;
                        end loop;

                        --  Make sure that the array ends here, in case there
                        --  previously a greater number of elements.

                        In_Tree.Array_Elements.Table
                          (New_Element).Next := No_Array_Element;
                     end if;
                  end;

               --  Declarations other that full associative arrays

               else
                  declare
                     New_Value : constant Variable_Value :=
                       Expression
                         (Project                => Project,
                          In_Tree                => In_Tree,
                          From_Project_Node      => From_Project_Node,
                          From_Project_Node_Tree => From_Project_Node_Tree,
                          Pkg                    => Pkg,
                          First_Term             =>
                            Tree.First_Term
                              (Expression_Of
                                   (Current_Item, From_Project_Node_Tree),
                               From_Project_Node_Tree),
                          Kind                   =>
                            Expression_Kind_Of
                              (Current_Item, From_Project_Node_Tree));
                     --  The expression value

                     The_Variable : Variable_Id := No_Variable;

                     Current_Item_Name : constant Name_Id :=
                       Name_Of (Current_Item, From_Project_Node_Tree);

                  begin
                     --  Process a typed variable declaration

                     if Kind_Of (Current_Item, From_Project_Node_Tree) =
                          N_Typed_Variable_Declaration
                     then
                        --  Report an error for an empty string

                        if New_Value.Value = Empty_String then
                           Error_Msg_Name_1 :=
                             Name_Of (Current_Item, From_Project_Node_Tree);

                           if Error_Report = null then
                              Error_Msg
                                ("no value defined for %",
                                 Location_Of
                                   (Current_Item, From_Project_Node_Tree));

                           else
                              Error_Report
                                ("no value defined for " &
                                 Get_Name_String (Error_Msg_Name_1),
                                 Project, In_Tree);
                           end if;

                        else
                           declare
                              Current_String : Project_Node_Id :=
                                                 First_Literal_String
                                                   (String_Type_Of
                                                      (Current_Item,
                                                       From_Project_Node_Tree),
                                                    From_Project_Node_Tree);

                           begin
                              --  Loop through all the valid strings for the
                              --  string type and compare to the string value.

                              while Current_String /= Empty_Node
                                and then
                                  String_Value_Of
                                    (Current_String, From_Project_Node_Tree) /=
                                                               New_Value.Value
                              loop
                                 Current_String :=
                                   Next_Literal_String
                                     (Current_String, From_Project_Node_Tree);
                              end loop;

                              --  Report an error if the string value is not
                              --  one for the string type.

                              if Current_String = Empty_Node then
                                 Error_Msg_Name_1 := New_Value.Value;
                                 Error_Msg_Name_2 :=
                                   Name_Of
                                     (Current_Item, From_Project_Node_Tree);

                                 if Error_Report = null then
                                    Error_Msg
                                      ("value { is illegal for typed string %",
                                       Location_Of
                                         (Current_Item,
                                          From_Project_Node_Tree));

                                 else
                                    Error_Report
                                      ("value """ &
                                       Get_Name_String (Error_Msg_Name_1) &
                                       """ is illegal for typed string """ &
                                       Get_Name_String (Error_Msg_Name_2) &
                                       """",
                                       Project, In_Tree);
                                 end if;
                              end if;
                           end;
                        end if;
                     end if;

                     if Kind_Of (Current_Item, From_Project_Node_Tree) /=
                          N_Attribute_Declaration
                       or else
                         Associative_Array_Index_Of
                           (Current_Item, From_Project_Node_Tree) = No_Name
                     then
                        --  Case of a variable declaration or of a not
                        --  associative array attribute.

                        --  First, find the list where to find the variable
                        --  or attribute.

                        if Kind_Of (Current_Item, From_Project_Node_Tree) =
                             N_Attribute_Declaration
                        then
                           if Pkg /= No_Package then
                              The_Variable :=
                                In_Tree.Packages.Table
                                  (Pkg).Decl.Attributes;
                           else
                              The_Variable :=
                                In_Tree.Projects.Table
                                  (Project).Decl.Attributes;
                           end if;

                        else
                           if Pkg /= No_Package then
                              The_Variable :=
                                In_Tree.Packages.Table
                                  (Pkg).Decl.Variables;
                           else
                              The_Variable :=
                                In_Tree.Projects.Table
                                  (Project).Decl.Variables;
                           end if;

                        end if;

                        --  Loop through the list, to find if it has already
                        --  been declared.

                        while The_Variable /= No_Variable
                          and then
                            In_Tree.Variable_Elements.Table
                              (The_Variable).Name /= Current_Item_Name
                        loop
                           The_Variable :=
                             In_Tree.Variable_Elements.Table
                               (The_Variable).Next;
                        end loop;

                        --  If it has not been declared, create a new entry
                        --  in the list.

                        if The_Variable = No_Variable then

                           --  All single string attribute should already have
                           --  been declared with a default empty string value.

                           pragma Assert
                             (Kind_Of (Current_Item, From_Project_Node_Tree) /=
                                N_Attribute_Declaration,
                              "illegal attribute declaration");

                           Variable_Element_Table.Increment_Last
                             (In_Tree.Variable_Elements);
                           The_Variable := Variable_Element_Table.Last
                             (In_Tree.Variable_Elements);

                           --  Put the new variable in the appropriate list

                           if Pkg /= No_Package then
                              In_Tree.Variable_Elements.Table (The_Variable) :=
                                (Next    =>
                                   In_Tree.Packages.Table
                                     (Pkg).Decl.Variables,
                                 Name    => Current_Item_Name,
                                 Value   => New_Value);
                              In_Tree.Packages.Table
                                (Pkg).Decl.Variables := The_Variable;

                           else
                              In_Tree.Variable_Elements.Table (The_Variable) :=
                                (Next    =>
                                   In_Tree.Projects.Table
                                     (Project).Decl.Variables,
                                 Name    => Current_Item_Name,
                                 Value   => New_Value);
                              In_Tree.Projects.Table
                                (Project).Decl.Variables :=
                                  The_Variable;
                           end if;

                        --  If the variable/attribute has already been
                        --  declared, just change the value.

                        else
                           In_Tree.Variable_Elements.Table
                             (The_Variable).Value :=
                                New_Value;

                        end if;

                     else
                        --  Associative array attribute

                        --  Get the string index

                        Get_Name_String
                          (Associative_Array_Index_Of
                             (Current_Item, From_Project_Node_Tree));

                        --  Put in lower case, if necessary

                        if Case_Insensitive
                             (Current_Item, From_Project_Node_Tree)
                        then
                           GNAT.Case_Util.To_Lower
                                            (Name_Buffer (1 .. Name_Len));
                        end if;

                        declare
                           The_Array : Array_Id;

                           The_Array_Element : Array_Element_Id :=
                                                 No_Array_Element;

                           Index_Name : constant Name_Id := Name_Find;
                           --  The name id of the index

                        begin
                           --  Look for the array in the appropriate list

                           if Pkg /= No_Package then
                              The_Array := In_Tree.Packages.Table
                                             (Pkg).Decl.Arrays;

                           else
                              The_Array := In_Tree.Projects.Table
                                             (Project).Decl.Arrays;
                           end if;

                           while
                             The_Array /= No_Array
                             and then In_Tree.Arrays.Table
                                        (The_Array).Name /= Current_Item_Name
                           loop
                              The_Array := In_Tree.Arrays.Table
                                             (The_Array).Next;
                           end loop;

                           --  If the array cannot be found, create a new
                           --  entry in the list. As The_Array_Element is
                           --  initialized to No_Array_Element, a new element
                           --  will be created automatically later.

                           if The_Array = No_Array then
                              Array_Table.Increment_Last
                                (In_Tree.Arrays);
                              The_Array := Array_Table.Last
                                (In_Tree.Arrays);

                              if Pkg /= No_Package then
                                 In_Tree.Arrays.Table
                                   (The_Array) :=
                                   (Name  => Current_Item_Name,
                                    Value => No_Array_Element,
                                    Next  =>
                                      In_Tree.Packages.Table
                                        (Pkg).Decl.Arrays);

                                 In_Tree.Packages.Table
                                   (Pkg).Decl.Arrays :=
                                     The_Array;

                              else
                                 In_Tree.Arrays.Table
                                   (The_Array) :=
                                   (Name  => Current_Item_Name,
                                    Value => No_Array_Element,
                                    Next  =>
                                      In_Tree.Projects.Table
                                        (Project).Decl.Arrays);

                                 In_Tree.Projects.Table
                                   (Project).Decl.Arrays :=
                                     The_Array;
                              end if;

                           --  Otherwise, initialize The_Array_Element as the
                           --  head of the element list.

                           else
                              The_Array_Element :=
                                In_Tree.Arrays.Table
                                  (The_Array).Value;
                           end if;

                           --  Look in the list, if any, to find an element
                           --  with the same index.

                           while The_Array_Element /= No_Array_Element
                             and then
                               In_Tree.Array_Elements.Table
                                 (The_Array_Element).Index /= Index_Name
                           loop
                              The_Array_Element :=
                                In_Tree.Array_Elements.Table
                                  (The_Array_Element).Next;
                           end loop;

                           --  If no such element were found, create a new
                           --  one and insert it in the element list, with
                           --  the propoer value.

                           if The_Array_Element = No_Array_Element then
                              Array_Element_Table.Increment_Last
                                (In_Tree.Array_Elements);
                              The_Array_Element := Array_Element_Table.Last
                                (In_Tree.Array_Elements);

                              In_Tree.Array_Elements.Table
                                (The_Array_Element) :=
                                (Index  => Index_Name,
                                 Src_Index =>
                                   Source_Index_Of
                                     (Current_Item, From_Project_Node_Tree),
                                 Index_Case_Sensitive =>
                                 not Case_Insensitive
                                   (Current_Item, From_Project_Node_Tree),
                                 Value  => New_Value,
                                 Next => In_Tree.Arrays.Table
                                           (The_Array).Value);
                              In_Tree.Arrays.Table
                                (The_Array).Value := The_Array_Element;

                           --  An element with the same index already exists,
                           --  just replace its value with the new one.

                           else
                              In_Tree.Array_Elements.Table
                                (The_Array_Element).Value := New_Value;
                           end if;
                        end;
                     end if;
                  end;
               end if;

            when N_Case_Construction =>
               declare
                  The_Project   : Project_Id      := Project;
                  --  The id of the project of the case variable

                  The_Package   : Package_Id      := Pkg;
                  --  The id of the package, if any, of the case variable

                  The_Variable  : Variable_Value  := Nil_Variable_Value;
                  --  The case variable

                  Case_Value    : Name_Id         := No_Name;
                  --  The case variable value

                  Case_Item     : Project_Node_Id := Empty_Node;
                  Choice_String : Project_Node_Id := Empty_Node;
                  Decl_Item     : Project_Node_Id := Empty_Node;

               begin
                  declare
                     Variable_Node : constant Project_Node_Id :=
                                       Case_Variable_Reference_Of
                                         (Current_Item,
                                          From_Project_Node_Tree);

                     Var_Id : Variable_Id := No_Variable;
                     Name   : Name_Id     := No_Name;

                  begin
                     --  If a project were specified for the case variable,
                     --  get its id.

                     if Project_Node_Of
                       (Variable_Node, From_Project_Node_Tree) /= Empty_Node
                     then
                        Name :=
                          Name_Of
                            (Project_Node_Of
                               (Variable_Node, From_Project_Node_Tree),
                             From_Project_Node_Tree);
                        The_Project :=
                          Imported_Or_Extended_Project_From
                            (Project, In_Tree, Name);
                     end if;

                     --  If a package were specified for the case variable,
                     --  get its id.

                     if Package_Node_Of
                       (Variable_Node, From_Project_Node_Tree) /= Empty_Node
                     then
                        Name :=
                          Name_Of
                            (Package_Node_Of
                               (Variable_Node, From_Project_Node_Tree),
                             From_Project_Node_Tree);
                        The_Package :=
                          Package_From (The_Project, In_Tree, Name);
                     end if;

                     Name := Name_Of (Variable_Node, From_Project_Node_Tree);

                     --  First, look for the case variable into the package,
                     --  if any.

                     if The_Package /= No_Package then
                        Var_Id := In_Tree.Packages.Table
                                    (The_Package).Decl.Variables;
                        Name :=
                          Name_Of (Variable_Node, From_Project_Node_Tree);
                        while Var_Id /= No_Variable
                          and then
                            In_Tree.Variable_Elements.Table
                              (Var_Id).Name /= Name
                        loop
                           Var_Id := In_Tree.Variable_Elements.
                                       Table (Var_Id).Next;
                        end loop;
                     end if;

                     --  If not found in the package, or if there is no
                     --  package, look at the project level.

                     if Var_Id = No_Variable
                        and then
                        Package_Node_Of
                          (Variable_Node, From_Project_Node_Tree) = Empty_Node
                     then
                        Var_Id := In_Tree.Projects.Table
                                    (The_Project).Decl.Variables;
                        while Var_Id /= No_Variable
                          and then
                            In_Tree.Variable_Elements.Table
                              (Var_Id).Name /= Name
                        loop
                           Var_Id := In_Tree.Variable_Elements.
                                       Table (Var_Id).Next;
                        end loop;
                     end if;

                     if Var_Id = No_Variable then

                        --  Should never happen, because this has already been
                        --  checked during parsing.

                        Write_Line ("variable """ &
                                    Get_Name_String (Name) &
                                    """ not found");
                        raise Program_Error;
                     end if;

                     --  Get the case variable

                     The_Variable := In_Tree.Variable_Elements.
                                       Table (Var_Id).Value;

                     if The_Variable.Kind /= Single then

                        --  Should never happen, because this has already been
                        --  checked during parsing.

                        Write_Line ("variable""" &
                                    Get_Name_String (Name) &
                                    """ is not a single string variable");
                        raise Program_Error;
                     end if;

                     --  Get the case variable value
                     Case_Value := The_Variable.Value;
                  end;

                  --  Now look into all the case items of the case construction

                  Case_Item :=
                    First_Case_Item_Of (Current_Item, From_Project_Node_Tree);
                  Case_Item_Loop :
                     while Case_Item /= Empty_Node loop
                        Choice_String :=
                          First_Choice_Of (Case_Item, From_Project_Node_Tree);

                        --  When Choice_String is nil, it means that it is
                        --  the "when others =>" alternative.

                        if Choice_String = Empty_Node then
                           Decl_Item :=
                             First_Declarative_Item_Of
                               (Case_Item, From_Project_Node_Tree);
                           exit Case_Item_Loop;
                        end if;

                        --  Look into all the alternative of this case item

                        Choice_Loop :
                           while Choice_String /= Empty_Node loop
                              if Case_Value =
                                String_Value_Of
                                  (Choice_String, From_Project_Node_Tree)
                              then
                                 Decl_Item :=
                                   First_Declarative_Item_Of
                                     (Case_Item, From_Project_Node_Tree);
                                 exit Case_Item_Loop;
                              end if;

                              Choice_String :=
                                Next_Literal_String
                                  (Choice_String, From_Project_Node_Tree);
                           end loop Choice_Loop;

                        Case_Item :=
                          Next_Case_Item (Case_Item, From_Project_Node_Tree);
                     end loop Case_Item_Loop;

                  --  If there is an alternative, then we process it

                  if Decl_Item /= Empty_Node then
                     Process_Declarative_Items
                       (Project                => Project,
                        In_Tree                => In_Tree,
                        From_Project_Node      => From_Project_Node,
                        From_Project_Node_Tree => From_Project_Node_Tree,
                        Pkg                    => Pkg,
                        Item                   => Decl_Item);
                  end if;
               end;

            when others =>

               --  Should never happen

               Write_Line ("Illegal declarative item: " &
                           Project_Node_Kind'Image
                             (Kind_Of
                                (Current_Item, From_Project_Node_Tree)));
               raise Program_Error;
         end case;
      end loop;
   end Process_Declarative_Items;

   ---------------------
   -- Recursive_Check --
   ---------------------

   procedure Recursive_Check
     (Project         : Project_Id;
      In_Tree         : Project_Tree_Ref;
      Follow_Links    : Boolean;
      When_No_Sources : Error_Warning)
   is
      Data                  : Project_Data;
      Imported_Project_List : Project_List := Empty_Project_List;

   begin
      --  Do nothing if Project is No_Project, or Project has already
      --  been marked as checked.

      if Project /= No_Project
        and then not In_Tree.Projects.Table (Project).Checked
      then
         --  Mark project as checked, to avoid infinite recursion in
         --  ill-formed trees, where a project imports itself.

         In_Tree.Projects.Table (Project).Checked := True;

         Data := In_Tree.Projects.Table (Project);

         --  Call itself for a possible extended project.
         --  (if there is no extended project, then nothing happens).

         Recursive_Check
           (Data.Extends, In_Tree, Follow_Links, When_No_Sources);

         --  Call itself for all imported projects

         Imported_Project_List := Data.Imported_Projects;
         while Imported_Project_List /= Empty_Project_List loop
            Recursive_Check
              (In_Tree.Project_Lists.Table
                 (Imported_Project_List).Project,
               In_Tree, Follow_Links, When_No_Sources);
            Imported_Project_List :=
              In_Tree.Project_Lists.Table
                (Imported_Project_List).Next;
         end loop;

         if Opt.Verbose_Mode then
            Write_Str ("Checking project file """);
            Write_Str (Get_Name_String (Data.Name));
            Write_Line ("""");
         end if;

         Prj.Nmsc.Check
           (Project, In_Tree, Error_Report, Follow_Links, When_No_Sources);
      end if;
   end Recursive_Check;

   -----------------------
   -- Recursive_Process --
   -----------------------

   procedure Recursive_Process
     (In_Tree                : Project_Tree_Ref;
      Project                : out Project_Id;
      From_Project_Node      : Project_Node_Id;
      From_Project_Node_Tree : Project_Node_Tree_Ref;
      Extended_By            : Project_Id)
   is
      With_Clause : Project_Node_Id;

   begin
      if From_Project_Node = Empty_Node then
         Project := No_Project;

      else
         declare
            Processed_Data   : Project_Data     := Empty_Project (In_Tree);
            Imported         : Project_List     := Empty_Project_List;
            Declaration_Node : Project_Node_Id  := Empty_Node;
            Tref             : Source_Buffer_Ptr;
            Name             : constant Name_Id :=
                                 Name_Of
                                   (From_Project_Node, From_Project_Node_Tree);
            Location         : Source_Ptr :=
                                 Location_Of
                                   (From_Project_Node, From_Project_Node_Tree);

         begin
            Project := Processed_Projects.Get (Name);

            if Project /= No_Project then
               return;
            end if;

            Project_Table.Increment_Last (In_Tree.Projects);
            Project := Project_Table.Last (In_Tree.Projects);
            Processed_Projects.Set (Name, Project);

            Processed_Data.Name := Name;

            Get_Name_String (Name);

            --  If name starts with the virtual prefix, flag the project as
            --  being a virtual extending project.

            if Name_Len > Virtual_Prefix'Length
              and then Name_Buffer (1 .. Virtual_Prefix'Length) =
                         Virtual_Prefix
            then
               Processed_Data.Virtual := True;
               Processed_Data.Display_Name := Name;

            --  If there is no file, for example when the project node tree is
            --  built in memory by GPS, the Display_Name cannot be found in
            --  the source, so its value is the same as Name.

            elsif Location = No_Location then
               Processed_Data.Display_Name := Name;

            --  Get the spelling of the project name from the project file

            else
               Tref := Source_Text (Get_Source_File_Index (Location));

               for J in 1 .. Name_Len loop
                  Name_Buffer (J) := Tref (Location);
                  Location := Location + 1;
               end loop;

               Processed_Data.Display_Name := Name_Find;
            end if;

            Processed_Data.Display_Path_Name :=
              Path_Name_Of (From_Project_Node, From_Project_Node_Tree);
            Get_Name_String (Processed_Data.Display_Path_Name);
            Canonical_Case_File_Name (Name_Buffer (1 .. Name_Len));
            Processed_Data.Path_Name := Name_Find;

            Processed_Data.Location :=
              Location_Of (From_Project_Node, From_Project_Node_Tree);

            Processed_Data.Display_Directory :=
              Directory_Of (From_Project_Node, From_Project_Node_Tree);
            Get_Name_String (Processed_Data.Display_Directory);
            Canonical_Case_File_Name (Name_Buffer (1 .. Name_Len));
            Processed_Data.Directory := Name_Find;

            Processed_Data.Extended_By := Extended_By;

            Add_Attributes
              (Project, In_Tree, Processed_Data.Decl, Attribute_First);
            With_Clause :=
              First_With_Clause_Of (From_Project_Node, From_Project_Node_Tree);

            while With_Clause /= Empty_Node loop
               declare
                  New_Project : Project_Id;
                  New_Data    : Project_Data;

               begin
                  Recursive_Process
                    (In_Tree                => In_Tree,
                     Project                => New_Project,
                     From_Project_Node      =>
                       Project_Node_Of (With_Clause, From_Project_Node_Tree),
                     From_Project_Node_Tree => From_Project_Node_Tree,
                     Extended_By            => No_Project);
                  New_Data :=
                    In_Tree.Projects.Table (New_Project);

                  --  If we were the first project to import it,
                  --  set First_Referred_By to us.

                  if New_Data.First_Referred_By = No_Project then
                     New_Data.First_Referred_By := Project;
                     In_Tree.Projects.Table (New_Project) :=
                       New_Data;
                  end if;

                  --  Add this project to our list of imported projects

                  Project_List_Table.Increment_Last
                    (In_Tree.Project_Lists);
                  In_Tree.Project_Lists.Table
                    (Project_List_Table.Last
                       (In_Tree.Project_Lists)) :=
                    (Project => New_Project, Next => Empty_Project_List);

                  --  Imported is the id of the last imported project.
                  --  If it is nil, then this imported project is our first.

                  if Imported = Empty_Project_List then
                     Processed_Data.Imported_Projects :=
                       Project_List_Table.Last
                         (In_Tree.Project_Lists);

                  else
                     In_Tree.Project_Lists.Table
                       (Imported).Next := Project_List_Table.Last
                          (In_Tree.Project_Lists);
                  end if;

                  Imported := Project_List_Table.Last
                                (In_Tree.Project_Lists);

                  With_Clause :=
                    Next_With_Clause_Of (With_Clause, From_Project_Node_Tree);
               end;
            end loop;

            Declaration_Node :=
              Project_Declaration_Of
                (From_Project_Node, From_Project_Node_Tree);

            Recursive_Process
              (In_Tree                => In_Tree,
               Project                => Processed_Data.Extends,
               From_Project_Node      =>
                 Extended_Project_Of
                   (Declaration_Node, From_Project_Node_Tree),
               From_Project_Node_Tree => From_Project_Node_Tree,
               Extended_By            => Project);

            In_Tree.Projects.Table (Project) := Processed_Data;

            Process_Declarative_Items
              (Project                => Project,
               In_Tree                => In_Tree,
               From_Project_Node      => From_Project_Node,
               From_Project_Node_Tree => From_Project_Node_Tree,
               Pkg                    => No_Package,
               Item                   =>
                 First_Declarative_Item_Of
                   (Declaration_Node, From_Project_Node_Tree));

            --  If it is an extending project, inherit all packages
            --  from the extended project that are not explicitely defined
            --  or renamed. Also inherit the languages, if attribute Languages
            --  is not explicitely defined.

            if Processed_Data.Extends /= No_Project then
               Processed_Data := In_Tree.Projects.Table (Project);

               declare
                  Extended_Pkg : Package_Id :=
                                   In_Tree.Projects.Table
                                     (Processed_Data.Extends).Decl.Packages;
                  Current_Pkg : Package_Id;
                  Element     : Package_Element;
                  First       : constant Package_Id :=
                                  Processed_Data.Decl.Packages;
                  Attribute1  : Variable_Id;
                  Attribute2  : Variable_Id;
                  Attr_Value1 : Variable;
                  Attr_Value2  : Variable;

               begin
                  while Extended_Pkg /= No_Package loop
                     Element :=
                       In_Tree.Packages.Table (Extended_Pkg);

                     Current_Pkg := First;

                     loop
                        exit when Current_Pkg = No_Package
                          or else In_Tree.Packages.Table
                                    (Current_Pkg).Name = Element.Name;
                        Current_Pkg := In_Tree.Packages.Table
                                         (Current_Pkg).Next;
                     end loop;

                     if Current_Pkg = No_Package then
                        Package_Table.Increment_Last
                          (In_Tree.Packages);
                        Current_Pkg := Package_Table.Last
                          (In_Tree.Packages);
                        In_Tree.Packages.Table (Current_Pkg) :=
                          (Name   => Element.Name,
                           Decl   => Element.Decl,
                           Parent => No_Package,
                           Next   => Processed_Data.Decl.Packages);
                        Processed_Data.Decl.Packages := Current_Pkg;
                     end if;

                     Extended_Pkg := Element.Next;
                  end loop;

                  --  Check if attribute Languages is declared in the
                  --  extending project.

                  Attribute1 := Processed_Data.Decl.Attributes;
                  while Attribute1 /= No_Variable loop
                     Attr_Value1 := In_Tree.Variable_Elements.
                                      Table (Attribute1);
                     exit when Attr_Value1.Name = Snames.Name_Languages;
                     Attribute1 := Attr_Value1.Next;
                  end loop;

                  if Attribute1 = No_Variable or else
                     Attr_Value1.Value.Default
                  then
                     --  Attribute Languages is not declared in the extending
                     --  project. Check if it is declared in the project being
                     --  extended.

                     Attribute2 :=
                       In_Tree.Projects.Table
                         (Processed_Data.Extends).Decl.Attributes;

                     while Attribute2 /= No_Variable loop
                        Attr_Value2 := In_Tree.Variable_Elements.
                                         Table (Attribute2);
                        exit when Attr_Value2.Name = Snames.Name_Languages;
                        Attribute2 := Attr_Value2.Next;
                     end loop;

                     if Attribute2 /= No_Variable and then
                        not Attr_Value2.Value.Default
                     then
                        --  As attribute Languages is declared in the project
                        --  being extended, copy its value for the extending
                        --  project.

                        if Attribute1 = No_Variable then
                           Variable_Element_Table.Increment_Last
                             (In_Tree.Variable_Elements);
                           Attribute1 := Variable_Element_Table.Last
                             (In_Tree.Variable_Elements);
                           Attr_Value1.Next := Processed_Data.Decl.Attributes;
                           Processed_Data.Decl.Attributes := Attribute1;
                        end if;

                        Attr_Value1.Name := Snames.Name_Languages;
                        Attr_Value1.Value := Attr_Value2.Value;
                        In_Tree.Variable_Elements.Table
                          (Attribute1) := Attr_Value1;
                     end if;
                  end if;
               end;

               In_Tree.Projects.Table (Project) := Processed_Data;
            end if;
         end;
      end if;
   end Recursive_Process;

end Prj.Proc;