| /* Target support for C++ classes on Windows. |
| Contributed by Danny Smith (dannysmith@users.sourceforge.net) |
| Copyright (C) 2005 |
| Free Software Foundation, Inc. |
| |
| This file is part of GCC. |
| |
| GCC is free software; you can redistribute it and/or modify it under |
| the terms of the GNU General Public License as published by the Free |
| Software Foundation; either version 2, or (at your option) any later |
| version. |
| |
| GCC is distributed in the hope that it will be useful, but WITHOUT 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 |
| along with GCC; see the file COPYING. If not, write to |
| the Free Software Foundation, 51 Franklin Street, Fifth Floor, |
| Boston, MA 02110-1301, USA. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "tm.h" |
| #include "rtl.h" |
| #include "regs.h" |
| #include "hard-reg-set.h" |
| #include "output.h" |
| #include "tree.h" |
| #include "cp/cp-tree.h" /* this is why we're a separate module */ |
| #include "flags.h" |
| #include "tm_p.h" |
| #include "toplev.h" |
| #include "hashtab.h" |
| |
| bool |
| i386_pe_type_dllimport_p (tree decl) |
| { |
| gcc_assert (TREE_CODE (decl) == VAR_DECL |
| || TREE_CODE (decl) == FUNCTION_DECL); |
| |
| if (TARGET_NOP_FUN_DLLIMPORT && TREE_CODE (decl) == FUNCTION_DECL) |
| return false; |
| |
| /* We ignore the dllimport attribute for inline member functions. |
| This differs from MSVC behavior which treats it like GNUC |
| 'extern inline' extension. Also ignore for template |
| instantiations with linkonce semantics and artificial methods. */ |
| if (TREE_CODE (decl) == FUNCTION_DECL |
| && (DECL_DECLARED_INLINE_P (decl) |
| || DECL_TEMPLATE_INSTANTIATION (decl) |
| || DECL_ARTIFICIAL (decl))) |
| return false; |
| |
| /* Since we can't treat a pointer to a dllimport'd symbol as a |
| constant address, we turn off the attribute on C++ virtual |
| methods to allow creation of vtables using thunks. */ |
| else if (TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE |
| && DECL_VIRTUAL_P (decl)) |
| { |
| /* Even though we ignore the attribute from the start, warn if we later see |
| an out-of class definition, as we do for other member functions in |
| tree.c:merge_dllimport_decl_attributes. If this is the key method, the |
| definition may affect the import-export status of vtables, depending |
| on how we handle MULTIPLE_SYMBOL_SPACES in cp/decl2.c. */ |
| if (DECL_INITIAL (decl)) |
| { |
| warning (OPT_Wattributes, "%q+D redeclared without dllimport attribute: " |
| "previous dllimport ignored", decl); |
| #ifdef PE_DLL_DEBUG |
| if (decl == CLASSTYPE_KEY_METHOD (DECL_CONTEXT (decl))) |
| warning (OPT_Wattributes, "key method %q+D of dllimport'd class defined" |
| decl); |
| #endif |
| } |
| return false; |
| } |
| |
| /* Don't mark defined functions as dllimport. This code will only be |
| reached if we see a non-inline function defined out-of-class. */ |
| else if (TREE_CODE (decl) == FUNCTION_DECL |
| && (DECL_INITIAL (decl))) |
| return false; |
| |
| /* Don't allow definitions of static data members in dllimport class, |
| If vtable data is marked as DECL_EXTERNAL, import it; otherwise just |
| ignore the class attribute. */ |
| else if (TREE_CODE (decl) == VAR_DECL |
| && TREE_STATIC (decl) && TREE_PUBLIC (decl) |
| && !DECL_EXTERNAL (decl)) |
| { |
| if (!DECL_VIRTUAL_P (decl)) |
| error ("definition of static data member %q+D of " |
| "dllimport'd class", decl); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| |
| bool |
| i386_pe_type_dllexport_p (tree decl) |
| { |
| gcc_assert (TREE_CODE (decl) == VAR_DECL |
| || TREE_CODE (decl) == FUNCTION_DECL); |
| /* Avoid exporting compiler-generated default dtors and copy ctors. |
| The only artificial methods that need to be exported are virtual |
| and non-virtual thunks. */ |
| if (TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE |
| && DECL_ARTIFICIAL (decl) && !DECL_THUNK_P (decl)) |
| return false; |
| return true; |
| } |
| |
| static inline void maybe_add_dllimport (tree decl) |
| { |
| if (i386_pe_type_dllimport_p (decl)) |
| DECL_DLLIMPORT_P (decl) = 1; |
| } |
| |
| void |
| i386_pe_adjust_class_at_definition (tree t) |
| { |
| tree member; |
| |
| gcc_assert (CLASS_TYPE_P (t)); |
| |
| /* We only look at dllimport. The only thing that dllexport does is |
| add stuff to a '.drectiv' section at end-of-file, so no need to do |
| anything for dllexport'd classes until we generate RTL. */ |
| if (lookup_attribute ("dllimport", TYPE_ATTRIBUTES (t)) == NULL_TREE) |
| return; |
| |
| /* We don't actually add the attribute to the decl, just set the flag |
| that signals that the address of this symbol is not a compile-time |
| constant. Any subsequent out-of-class declaration of members wil |
| cause the DECL_DLLIMPORT_P flag to be unset. |
| (See tree.c: merge_dllimport_decl_attributes). |
| That is just right since out-of class declarations can only be a |
| definition. We recheck the class members at RTL generation to |
| emit warnings if this has happened. Definition of static data member |
| of dllimport'd class always causes an error (as per MS compiler). |
| */ |
| |
| /* Check static VAR_DECL's. */ |
| for (member = TYPE_FIELDS (t); member; member = TREE_CHAIN (member)) |
| if (TREE_CODE (member) == VAR_DECL) |
| maybe_add_dllimport (member); |
| |
| /* Check FUNCTION_DECL's. */ |
| for (member = TYPE_METHODS (t); member; member = TREE_CHAIN (member)) |
| if (TREE_CODE (member) == FUNCTION_DECL) |
| maybe_add_dllimport (member); |
| |
| /* Check vtables */ |
| for (member = CLASSTYPE_VTABLES (t); member; member = TREE_CHAIN (member)) |
| if (TREE_CODE (member) == VAR_DECL) |
| maybe_add_dllimport (member); |
| |
| /* We leave typeinfo tables alone. We can't mark TI objects as |
| dllimport, since the address of a secondary VTT may be needed |
| for static initialization of a primary VTT. VTT's of |
| dllimport'd classes should always be link-once COMDAT. */ |
| } |