1 /* Handle the hair of processing (but not expanding) inline functions.
2 Also manage function and variable name overloading.
3 Copyright (C) 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
4 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
5 Free Software Foundation, Inc.
6 Contributed by Michael Tiemann (tiemann@cygnus.com)
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
25 /* Handle method declarations. */
28 #include "coretypes.h"
37 #include "common/common-target.h"
38 #include "tree-pass.h"
39 #include "diagnostic.h"
43 /* Various flags to control the mangling process. */
49 /* The thing we are presently mangling is part of a template type,
50 rather than a fully instantiated type. Therefore, we may see
51 complex expressions where we would normally expect to see a
52 simple integer constant. */
53 mf_maybe_uninstantiated = 1,
54 /* When mangling a numeric value, use the form `_XX_' (instead of
55 just `XX') if the value has more than one digit. */
56 mf_use_underscores_around_value = 2
59 typedef enum mangling_flags mangling_flags;
61 static void do_build_copy_assign (tree);
62 static void do_build_copy_constructor (tree);
63 static tree make_alias_for_thunk (tree);
65 /* Called once to initialize method.c. */
73 /* Return a this or result adjusting thunk to FUNCTION. THIS_ADJUSTING
74 indicates whether it is a this or result adjusting thunk.
75 FIXED_OFFSET and VIRTUAL_OFFSET indicate how to do the adjustment
76 (see thunk_adjust). VIRTUAL_OFFSET can be NULL, but FIXED_OFFSET
77 never is. VIRTUAL_OFFSET is the /index/ into the vtable for this
78 adjusting thunks, we scale it to a byte offset. For covariant
79 thunks VIRTUAL_OFFSET is the virtual binfo. You must post process
80 the returned thunk with finish_thunk. */
83 make_thunk (tree function, bool this_adjusting,
84 tree fixed_offset, tree virtual_offset)
89 gcc_assert (TREE_CODE (function) == FUNCTION_DECL);
90 /* We can have this thunks to covariant thunks, but not vice versa. */
91 gcc_assert (!DECL_THIS_THUNK_P (function));
92 gcc_assert (!DECL_RESULT_THUNK_P (function) || this_adjusting);
94 /* Scale the VIRTUAL_OFFSET to be in terms of bytes. */
95 if (this_adjusting && virtual_offset)
97 = size_binop (MULT_EXPR,
100 TYPE_SIZE_UNIT (vtable_entry_type)));
102 d = tree_low_cst (fixed_offset, 0);
104 /* See if we already have the thunk in question. For this_adjusting
105 thunks VIRTUAL_OFFSET will be an INTEGER_CST, for covariant thunks it
107 for (thunk = DECL_THUNKS (function); thunk; thunk = DECL_CHAIN (thunk))
108 if (DECL_THIS_THUNK_P (thunk) == this_adjusting
109 && THUNK_FIXED_OFFSET (thunk) == d
110 && !virtual_offset == !THUNK_VIRTUAL_OFFSET (thunk)
113 ? tree_int_cst_equal (THUNK_VIRTUAL_OFFSET (thunk),
115 : THUNK_VIRTUAL_OFFSET (thunk) == virtual_offset)))
118 /* All thunks must be created before FUNCTION is actually emitted;
119 the ABI requires that all thunks be emitted together with the
120 function to which they transfer control. */
121 gcc_assert (!TREE_ASM_WRITTEN (function));
122 /* Likewise, we can only be adding thunks to a function declared in
123 the class currently being laid out. */
124 gcc_assert (TYPE_SIZE (DECL_CONTEXT (function))
125 && TYPE_BEING_DEFINED (DECL_CONTEXT (function)));
127 thunk = build_decl (DECL_SOURCE_LOCATION (function),
128 FUNCTION_DECL, NULL_TREE, TREE_TYPE (function));
129 DECL_LANG_SPECIFIC (thunk) = DECL_LANG_SPECIFIC (function);
130 cxx_dup_lang_specific_decl (thunk);
131 DECL_THUNKS (thunk) = NULL_TREE;
133 DECL_CONTEXT (thunk) = DECL_CONTEXT (function);
134 TREE_READONLY (thunk) = TREE_READONLY (function);
135 TREE_THIS_VOLATILE (thunk) = TREE_THIS_VOLATILE (function);
136 TREE_PUBLIC (thunk) = TREE_PUBLIC (function);
137 SET_DECL_THUNK_P (thunk, this_adjusting);
138 THUNK_TARGET (thunk) = function;
139 THUNK_FIXED_OFFSET (thunk) = d;
140 THUNK_VIRTUAL_OFFSET (thunk) = virtual_offset;
141 THUNK_ALIAS (thunk) = NULL_TREE;
143 DECL_INTERFACE_KNOWN (thunk) = 1;
144 DECL_NOT_REALLY_EXTERN (thunk) = 1;
145 DECL_COMDAT (thunk) = DECL_COMDAT (function);
146 DECL_SAVED_FUNCTION_DATA (thunk) = NULL;
147 /* The thunk itself is not a constructor or destructor, even if
148 the thing it is thunking to is. */
149 DECL_DESTRUCTOR_P (thunk) = 0;
150 DECL_CONSTRUCTOR_P (thunk) = 0;
151 DECL_EXTERNAL (thunk) = 1;
152 DECL_ARTIFICIAL (thunk) = 1;
153 /* The THUNK is not a pending inline, even if the FUNCTION is. */
154 DECL_PENDING_INLINE_P (thunk) = 0;
155 DECL_DECLARED_INLINE_P (thunk) = 0;
156 /* Nor is it a template instantiation. */
157 DECL_USE_TEMPLATE (thunk) = 0;
158 DECL_TEMPLATE_INFO (thunk) = NULL;
160 /* Add it to the list of thunks associated with FUNCTION. */
161 DECL_CHAIN (thunk) = DECL_THUNKS (function);
162 DECL_THUNKS (function) = thunk;
167 /* Finish THUNK, a thunk decl. */
170 finish_thunk (tree thunk)
173 tree fixed_offset = ssize_int (THUNK_FIXED_OFFSET (thunk));
174 tree virtual_offset = THUNK_VIRTUAL_OFFSET (thunk);
176 gcc_assert (!DECL_NAME (thunk) && DECL_THUNK_P (thunk));
177 if (virtual_offset && DECL_RESULT_THUNK_P (thunk))
178 virtual_offset = BINFO_VPTR_FIELD (virtual_offset);
179 function = THUNK_TARGET (thunk);
180 name = mangle_thunk (function, DECL_THIS_THUNK_P (thunk),
181 fixed_offset, virtual_offset);
183 /* We can end up with declarations of (logically) different
184 covariant thunks, that do identical adjustments. The two thunks
185 will be adjusting between within different hierarchies, which
186 happen to have the same layout. We must nullify one of them to
187 refer to the other. */
188 if (DECL_RESULT_THUNK_P (thunk))
192 for (cov_probe = DECL_THUNKS (function);
193 cov_probe; cov_probe = DECL_CHAIN (cov_probe))
194 if (DECL_NAME (cov_probe) == name)
196 gcc_assert (!DECL_THUNKS (thunk));
197 THUNK_ALIAS (thunk) = (THUNK_ALIAS (cov_probe)
198 ? THUNK_ALIAS (cov_probe) : cov_probe);
203 DECL_NAME (thunk) = name;
204 SET_DECL_ASSEMBLER_NAME (thunk, name);
207 static GTY (()) int thunk_labelno;
209 /* Create a static alias to target. */
212 make_alias_for (tree target, tree newid)
214 tree alias = build_decl (DECL_SOURCE_LOCATION (target),
215 TREE_CODE (target), newid, TREE_TYPE (target));
216 DECL_LANG_SPECIFIC (alias) = DECL_LANG_SPECIFIC (target);
217 cxx_dup_lang_specific_decl (alias);
218 DECL_CONTEXT (alias) = NULL;
219 TREE_READONLY (alias) = TREE_READONLY (target);
220 TREE_THIS_VOLATILE (alias) = TREE_THIS_VOLATILE (target);
221 TREE_PUBLIC (alias) = 0;
222 DECL_INTERFACE_KNOWN (alias) = 1;
223 if (DECL_LANG_SPECIFIC (alias))
225 DECL_NOT_REALLY_EXTERN (alias) = 1;
226 DECL_USE_TEMPLATE (alias) = 0;
227 DECL_TEMPLATE_INFO (alias) = NULL;
229 DECL_EXTERNAL (alias) = 0;
230 DECL_ARTIFICIAL (alias) = 1;
231 DECL_TEMPLATE_INSTANTIATED (alias) = 0;
232 if (TREE_CODE (alias) == FUNCTION_DECL)
234 DECL_SAVED_FUNCTION_DATA (alias) = NULL;
235 DECL_DESTRUCTOR_P (alias) = 0;
236 DECL_CONSTRUCTOR_P (alias) = 0;
237 DECL_PENDING_INLINE_P (alias) = 0;
238 DECL_DECLARED_INLINE_P (alias) = 0;
239 DECL_INITIAL (alias) = error_mark_node;
240 DECL_ARGUMENTS (alias) = copy_list (DECL_ARGUMENTS (target));
243 TREE_STATIC (alias) = 1;
244 TREE_ADDRESSABLE (alias) = 1;
245 TREE_USED (alias) = 1;
246 SET_DECL_ASSEMBLER_NAME (alias, DECL_NAME (alias));
247 TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias)) = 1;
252 make_alias_for_thunk (tree function)
257 targetm.asm_out.generate_internal_label (buf, "LTHUNK", thunk_labelno);
260 alias = make_alias_for (function, get_identifier (buf));
262 if (!flag_syntax_only)
264 struct cgraph_node *funcn, *aliasn;
265 funcn = cgraph_get_node (function);
266 gcc_checking_assert (funcn);
267 aliasn = cgraph_same_body_alias (funcn, alias, function);
268 DECL_ASSEMBLER_NAME (function);
269 gcc_assert (aliasn != NULL);
275 /* Emit the definition of a C++ multiple inheritance or covariant
276 return vtable thunk. If EMIT_P is nonzero, the thunk is emitted
280 use_thunk (tree thunk_fndecl, bool emit_p)
282 tree a, t, function, alias;
284 HOST_WIDE_INT fixed_offset, virtual_value;
285 bool this_adjusting = DECL_THIS_THUNK_P (thunk_fndecl);
286 struct cgraph_node *funcn, *thunk_node;
288 /* We should have called finish_thunk to give it a name. */
289 gcc_assert (DECL_NAME (thunk_fndecl));
291 /* We should never be using an alias, always refer to the
293 gcc_assert (!THUNK_ALIAS (thunk_fndecl));
295 if (TREE_ASM_WRITTEN (thunk_fndecl))
298 function = THUNK_TARGET (thunk_fndecl);
299 if (DECL_RESULT (thunk_fndecl))
300 /* We already turned this thunk into an ordinary function.
301 There's no need to process this thunk again. */
304 if (DECL_THUNK_P (function))
305 /* The target is itself a thunk, process it now. */
306 use_thunk (function, emit_p);
308 /* Thunks are always addressable; they only appear in vtables. */
309 TREE_ADDRESSABLE (thunk_fndecl) = 1;
311 /* Figure out what function is being thunked to. It's referenced in
312 this translation unit. */
313 TREE_ADDRESSABLE (function) = 1;
314 mark_used (function);
318 if (TARGET_USE_LOCAL_THUNK_ALIAS_P (function))
319 alias = make_alias_for_thunk (function);
323 fixed_offset = THUNK_FIXED_OFFSET (thunk_fndecl);
324 virtual_offset = THUNK_VIRTUAL_OFFSET (thunk_fndecl);
329 virtual_offset = BINFO_VPTR_FIELD (virtual_offset);
330 virtual_value = tree_low_cst (virtual_offset, /*pos=*/0);
331 gcc_assert (virtual_value);
336 /* And, if we need to emit the thunk, it's used. */
337 mark_used (thunk_fndecl);
338 /* This thunk is actually defined. */
339 DECL_EXTERNAL (thunk_fndecl) = 0;
340 /* The linkage of the function may have changed. FIXME in linkage
342 TREE_PUBLIC (thunk_fndecl) = TREE_PUBLIC (function);
343 DECL_VISIBILITY (thunk_fndecl) = DECL_VISIBILITY (function);
344 DECL_VISIBILITY_SPECIFIED (thunk_fndecl)
345 = DECL_VISIBILITY_SPECIFIED (function);
346 DECL_COMDAT (thunk_fndecl) = DECL_COMDAT (function);
347 DECL_WEAK (thunk_fndecl) = DECL_WEAK (function);
349 if (flag_syntax_only)
351 TREE_ASM_WRITTEN (thunk_fndecl) = 1;
355 push_to_top_level ();
357 if (TARGET_USE_LOCAL_THUNK_ALIAS_P (function)
358 && targetm_common.have_named_sections)
360 resolve_unique_section (function, 0, flag_function_sections);
362 if (DECL_SECTION_NAME (function) != NULL && DECL_ONE_ONLY (function))
364 resolve_unique_section (thunk_fndecl, 0, flag_function_sections);
366 /* Output the thunk into the same section as function. */
367 DECL_SECTION_NAME (thunk_fndecl) = DECL_SECTION_NAME (function);
371 /* Set up cloned argument trees for the thunk. */
373 for (a = DECL_ARGUMENTS (function); a; a = DECL_CHAIN (a))
375 tree x = copy_node (a);
377 DECL_CONTEXT (x) = thunk_fndecl;
378 SET_DECL_RTL (x, NULL);
379 DECL_HAS_VALUE_EXPR_P (x) = 0;
380 TREE_ADDRESSABLE (x) = 0;
384 DECL_ARGUMENTS (thunk_fndecl) = a;
385 TREE_ASM_WRITTEN (thunk_fndecl) = 1;
386 funcn = cgraph_get_node (function);
387 gcc_checking_assert (funcn);
388 thunk_node = cgraph_add_thunk (funcn, thunk_fndecl, function,
389 this_adjusting, fixed_offset, virtual_value,
390 virtual_offset, alias);
391 if (DECL_ONE_ONLY (function))
392 cgraph_add_to_same_comdat_group (thunk_node, funcn);
395 || !targetm.asm_out.can_output_mi_thunk (thunk_fndecl, fixed_offset,
396 virtual_value, alias))
398 /* If this is a covariant thunk, or we don't have the necessary
399 code for efficient thunks, generate a thunk function that
400 just makes a call to the real function. Unfortunately, this
401 doesn't work for varargs. */
403 if (varargs_function_p (function))
404 error ("generic thunk code fails for method %q#D which uses %<...%>",
408 pop_from_top_level ();
411 /* Code for synthesizing methods which have default semantics defined. */
413 /* True iff CTYPE has a trivial SFK. */
416 type_has_trivial_fn (tree ctype, special_function_kind sfk)
420 case sfk_constructor:
421 return !TYPE_HAS_COMPLEX_DFLT (ctype);
422 case sfk_copy_constructor:
423 return !TYPE_HAS_COMPLEX_COPY_CTOR (ctype);
424 case sfk_move_constructor:
425 return !TYPE_HAS_COMPLEX_MOVE_CTOR (ctype);
426 case sfk_copy_assignment:
427 return !TYPE_HAS_COMPLEX_COPY_ASSIGN (ctype);
428 case sfk_move_assignment:
429 return !TYPE_HAS_COMPLEX_MOVE_ASSIGN (ctype);
431 return !TYPE_HAS_NONTRIVIAL_DESTRUCTOR (ctype);
437 /* Note that CTYPE has a non-trivial SFK even though we previously thought
441 type_set_nontrivial_flag (tree ctype, special_function_kind sfk)
445 case sfk_constructor:
446 TYPE_HAS_COMPLEX_DFLT (ctype) = true;
448 case sfk_copy_constructor:
449 TYPE_HAS_COMPLEX_COPY_CTOR (ctype) = true;
451 case sfk_move_constructor:
452 TYPE_HAS_COMPLEX_MOVE_CTOR (ctype) = true;
454 case sfk_copy_assignment:
455 TYPE_HAS_COMPLEX_COPY_ASSIGN (ctype) = true;
457 case sfk_move_assignment:
458 TYPE_HAS_COMPLEX_MOVE_ASSIGN (ctype) = true;
461 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (ctype) = true;
468 /* True iff FN is a trivial defaulted member function ([cd]tor, op=). */
471 trivial_fn_p (tree fn)
473 if (!DECL_DEFAULTED_FN (fn))
476 /* If fn is a clone, get the primary variant. */
477 fn = DECL_ORIGIN (fn);
478 return type_has_trivial_fn (DECL_CONTEXT (fn), special_function_p (fn));
481 /* Generate code for default X(X&) or X(X&&) constructor. */
484 do_build_copy_constructor (tree fndecl)
486 tree parm = FUNCTION_FIRST_USER_PARM (fndecl);
487 bool move_p = DECL_MOVE_CONSTRUCTOR_P (fndecl);
488 bool trivial = trivial_fn_p (fndecl);
490 parm = convert_from_reference (parm);
493 && is_empty_class (current_class_type))
494 /* Don't copy the padding byte; it might not have been allocated
495 if *this is a base subobject. */;
498 tree t = build2 (INIT_EXPR, void_type_node, current_class_ref, parm);
499 finish_expr_stmt (t);
503 tree fields = TYPE_FIELDS (current_class_type);
504 tree member_init_list = NULL_TREE;
505 int cvquals = cp_type_quals (TREE_TYPE (parm));
507 tree binfo, base_binfo;
509 VEC(tree,gc) *vbases;
511 /* Initialize all the base-classes with the parameter converted
512 to their type so that we get their copy constructor and not
513 another constructor that takes current_class_type. We must
514 deal with the binfo's directly as a direct base might be
515 inaccessible due to ambiguity. */
516 for (vbases = CLASSTYPE_VBASECLASSES (current_class_type), i = 0;
517 VEC_iterate (tree, vbases, i, binfo); i++)
519 init = build_base_path (PLUS_EXPR, parm, binfo, 1);
524 build_tree_list (NULL_TREE, init),
528 for (binfo = TYPE_BINFO (current_class_type), i = 0;
529 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
531 if (BINFO_VIRTUAL_P (base_binfo))
534 init = build_base_path (PLUS_EXPR, parm, base_binfo, 1);
538 = tree_cons (base_binfo,
539 build_tree_list (NULL_TREE, init),
543 for (; fields; fields = DECL_CHAIN (fields))
548 if (TREE_CODE (field) != FIELD_DECL)
551 expr_type = TREE_TYPE (field);
552 if (DECL_NAME (field))
554 if (VFIELD_NAME_P (DECL_NAME (field)))
557 else if (ANON_AGGR_TYPE_P (expr_type) && TYPE_FIELDS (expr_type))
558 /* Just use the field; anonymous types can't have
559 nontrivial copy ctors or assignment ops or this
560 function would be deleted. */;
564 /* Compute the type of "init->field". If the copy-constructor
565 parameter is, for example, "const S&", and the type of
566 the field is "T", then the type will usually be "const
567 T". (There are no cv-qualified variants of reference
569 if (TREE_CODE (expr_type) != REFERENCE_TYPE)
573 if (DECL_MUTABLE_P (field))
574 quals &= ~TYPE_QUAL_CONST;
575 quals |= cp_type_quals (expr_type);
576 expr_type = cp_build_qualified_type (expr_type, quals);
579 init = build3 (COMPONENT_REF, expr_type, parm, field, NULL_TREE);
580 if (move_p && TREE_CODE (expr_type) != REFERENCE_TYPE)
582 init = build_tree_list (NULL_TREE, init);
584 member_init_list = tree_cons (field, init, member_init_list);
586 finish_mem_initializers (member_init_list);
591 do_build_copy_assign (tree fndecl)
593 tree parm = DECL_CHAIN (DECL_ARGUMENTS (fndecl));
595 bool move_p = move_fn_p (fndecl);
596 bool trivial = trivial_fn_p (fndecl);
597 int flags = LOOKUP_NORMAL | LOOKUP_NONVIRTUAL | LOOKUP_DEFAULTED;
599 compound_stmt = begin_compound_stmt (0);
600 parm = convert_from_reference (parm);
603 && is_empty_class (current_class_type))
604 /* Don't copy the padding byte; it might not have been allocated
605 if *this is a base subobject. */;
608 tree t = build2 (MODIFY_EXPR, void_type_node, current_class_ref, parm);
609 finish_expr_stmt (t);
614 int cvquals = cp_type_quals (TREE_TYPE (parm));
616 tree binfo, base_binfo;
618 /* Assign to each of the direct base classes. */
619 for (binfo = TYPE_BINFO (current_class_type), i = 0;
620 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
623 VEC(tree,gc) *parmvec;
625 /* We must convert PARM directly to the base class
626 explicitly since the base class may be ambiguous. */
627 converted_parm = build_base_path (PLUS_EXPR, parm, base_binfo, 1);
629 converted_parm = move (converted_parm);
630 /* Call the base class assignment operator. */
631 parmvec = make_tree_vector_single (converted_parm);
633 (build_special_member_call (current_class_ref,
634 ansi_assopname (NOP_EXPR),
638 tf_warning_or_error));
639 release_tree_vector (parmvec);
642 /* Assign to each of the non-static data members. */
643 for (fields = TYPE_FIELDS (current_class_type);
645 fields = DECL_CHAIN (fields))
647 tree comp = current_class_ref;
653 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
656 expr_type = TREE_TYPE (field);
658 if (CP_TYPE_CONST_P (expr_type))
660 error ("non-static const member %q#D, can%'t use default "
661 "assignment operator", field);
664 else if (TREE_CODE (expr_type) == REFERENCE_TYPE)
666 error ("non-static reference member %q#D, can%'t use "
667 "default assignment operator", field);
671 if (DECL_NAME (field))
673 if (VFIELD_NAME_P (DECL_NAME (field)))
676 else if (ANON_AGGR_TYPE_P (expr_type)
677 && TYPE_FIELDS (expr_type) != NULL_TREE)
678 /* Just use the field; anonymous types can't have
679 nontrivial copy ctors or assignment ops or this
680 function would be deleted. */;
684 comp = build3 (COMPONENT_REF, expr_type, comp, field, NULL_TREE);
686 /* Compute the type of init->field */
688 if (DECL_MUTABLE_P (field))
689 quals &= ~TYPE_QUAL_CONST;
690 expr_type = cp_build_qualified_type (expr_type, quals);
692 init = build3 (COMPONENT_REF, expr_type, init, field, NULL_TREE);
693 if (move_p && TREE_CODE (expr_type) != REFERENCE_TYPE)
696 if (DECL_NAME (field))
697 init = cp_build_modify_expr (comp, NOP_EXPR, init,
698 tf_warning_or_error);
700 init = build2 (MODIFY_EXPR, TREE_TYPE (comp), comp, init);
701 finish_expr_stmt (init);
704 finish_return_stmt (current_class_ref);
705 finish_compound_stmt (compound_stmt);
708 /* Synthesize FNDECL, a non-static member function. */
711 synthesize_method (tree fndecl)
713 bool nested = (current_function_decl != NULL_TREE);
714 tree context = decl_function_context (fndecl);
715 bool need_body = true;
717 location_t save_input_location = input_location;
718 int error_count = errorcount;
719 int warning_count = warningcount;
721 /* Reset the source location, we might have been previously
722 deferred, and thus have saved where we were first needed. */
723 DECL_SOURCE_LOCATION (fndecl)
724 = DECL_SOURCE_LOCATION (TYPE_NAME (DECL_CONTEXT (fndecl)));
726 /* If we've been asked to synthesize a clone, just synthesize the
727 cloned function instead. Doing so will automatically fill in the
728 body for the clone. */
729 if (DECL_CLONED_FUNCTION_P (fndecl))
730 fndecl = DECL_CLONED_FUNCTION (fndecl);
732 /* We may be in the middle of deferred access check. Disable
734 push_deferring_access_checks (dk_no_deferred);
737 push_to_top_level ();
739 push_function_context ();
741 input_location = DECL_SOURCE_LOCATION (fndecl);
743 start_preparsed_function (fndecl, NULL_TREE, SF_DEFAULT | SF_PRE_PARSED);
744 stmt = begin_function_body ();
746 if (DECL_OVERLOADED_OPERATOR_P (fndecl) == NOP_EXPR)
748 do_build_copy_assign (fndecl);
751 else if (DECL_CONSTRUCTOR_P (fndecl))
753 tree arg_chain = FUNCTION_FIRST_USER_PARMTYPE (fndecl);
754 if (arg_chain != void_list_node)
755 do_build_copy_constructor (fndecl);
757 finish_mem_initializers (NULL_TREE);
760 /* If we haven't yet generated the body of the function, just
761 generate an empty compound statement. */
765 compound_stmt = begin_compound_stmt (BCS_FN_BODY);
766 finish_compound_stmt (compound_stmt);
769 finish_function_body (stmt);
770 expand_or_defer_fn (finish_function (0));
772 input_location = save_input_location;
775 pop_from_top_level ();
777 pop_function_context ();
779 pop_deferring_access_checks ();
781 if (error_count != errorcount || warning_count != warningcount)
782 inform (input_location, "synthesized method %qD first required here ",
786 /* Build a reference to type TYPE with cv-quals QUALS, which is an
787 rvalue if RVALUE is true. */
790 build_stub_type (tree type, int quals, bool rvalue)
792 tree argtype = cp_build_qualified_type (type, quals);
793 return cp_build_reference_type (argtype, rvalue);
796 /* Build a dummy glvalue from dereferencing a dummy reference of type
800 build_stub_object (tree reftype)
802 tree stub = build1 (NOP_EXPR, reftype, integer_one_node);
803 return convert_from_reference (stub);
806 /* Determine which function will be called when looking up NAME in TYPE,
807 called with a single ARGTYPE argument, or no argument if ARGTYPE is
808 null. FLAGS and COMPLAIN are as for build_new_method_call.
810 Returns a FUNCTION_DECL if all is well.
811 Returns NULL_TREE if overload resolution failed.
812 Returns error_mark_node if the chosen function cannot be called. */
815 locate_fn_flags (tree type, tree name, tree argtype, int flags,
816 tsubst_flags_t complain)
818 tree ob, fn, fns, binfo, rval;
822 binfo = TYPE_BINFO (type);
826 type = BINFO_TYPE (binfo);
829 ob = build_stub_object (cp_build_reference_type (type, false));
830 args = make_tree_vector ();
833 tree arg = build_stub_object (argtype);
834 VEC_quick_push (tree, args, arg);
837 fns = lookup_fnfields (binfo, name, 0);
838 rval = build_new_method_call (ob, fns, &args, binfo, flags, &fn, complain);
840 release_tree_vector (args);
841 if (fn && rval == error_mark_node)
847 /* Locate the dtor of TYPE. */
850 get_dtor (tree type, tsubst_flags_t complain)
852 tree fn = locate_fn_flags (type, complete_dtor_identifier, NULL_TREE,
853 LOOKUP_NORMAL, complain);
854 if (fn == error_mark_node)
859 /* Locate the default ctor of TYPE. */
862 locate_ctor (tree type)
866 push_deferring_access_checks (dk_no_check);
867 fn = locate_fn_flags (type, complete_ctor_identifier, NULL_TREE,
868 LOOKUP_SPECULATIVE, tf_none);
869 pop_deferring_access_checks ();
870 if (fn == error_mark_node)
875 /* Likewise, but give any appropriate errors. */
878 get_default_ctor (tree type)
880 tree fn = locate_fn_flags (type, complete_ctor_identifier, NULL_TREE,
881 LOOKUP_NORMAL, tf_warning_or_error);
882 if (fn == error_mark_node)
887 /* Locate the copy ctor of TYPE. */
890 get_copy_ctor (tree type, tsubst_flags_t complain)
892 int quals = (TYPE_HAS_CONST_COPY_CTOR (type)
893 ? TYPE_QUAL_CONST : TYPE_UNQUALIFIED);
894 tree argtype = build_stub_type (type, quals, false);
895 tree fn = locate_fn_flags (type, complete_ctor_identifier, argtype,
896 LOOKUP_NORMAL, complain);
897 if (fn == error_mark_node)
902 /* Locate the copy assignment operator of TYPE. */
905 get_copy_assign (tree type)
907 int quals = (TYPE_HAS_CONST_COPY_ASSIGN (type)
908 ? TYPE_QUAL_CONST : TYPE_UNQUALIFIED);
909 tree argtype = build_stub_type (type, quals, false);
910 tree fn = locate_fn_flags (type, ansi_assopname (NOP_EXPR), argtype,
911 LOOKUP_NORMAL, tf_warning_or_error);
912 if (fn == error_mark_node)
917 /* Subroutine of synthesized_method_walk. Update SPEC_P, TRIVIAL_P and
918 DELETED_P or give an error message MSG with argument ARG. */
921 process_subob_fn (tree fn, bool move_p, tree *spec_p, bool *trivial_p,
922 bool *deleted_p, bool *constexpr_p,
923 const char *msg, tree arg)
925 if (!fn || fn == error_mark_node)
930 tree raises = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn));
931 *spec_p = merge_exception_specifiers (*spec_p, raises, fn);
934 if (!trivial_fn_p (fn))
938 if (TREE_CODE (arg) == FIELD_DECL
939 && TREE_CODE (DECL_CONTEXT (arg)) == UNION_TYPE)
944 error ("union member %q+D with non-trivial %qD", arg, fn);
948 if (move_p && !move_fn_p (fn) && !trivial_fn_p (fn))
957 /* If this is a specialization of a constexpr template, we need to
958 force the instantiation now so that we know whether or not it's
960 if (DECL_DECLARED_CONSTEXPR_P (fn) && DECL_TEMPLATE_INSTANTIATION (fn)
961 && !DECL_TEMPLATE_INSTANTIATED (fn))
962 instantiate_decl (fn, /*defer_ok*/false, /*expl_class*/false);
963 if (!DECL_DECLARED_CONSTEXPR_P (fn))
965 *constexpr_p = false;
968 inform (0, "defaulted constructor calls non-constexpr "
970 explain_invalid_constexpr_fn (fn);
982 /* Subroutine of synthesized_method_walk to allow recursion into anonymous
986 walk_field_subobs (tree fields, tree fnname, special_function_kind sfk,
987 int quals, bool copy_arg_p, bool move_p,
988 bool assign_p, tree *spec_p, bool *trivial_p,
989 bool *deleted_p, bool *constexpr_p, const char *msg,
990 int flags, tsubst_flags_t complain)
993 for (field = fields; field; field = DECL_CHAIN (field))
995 tree mem_type, argtype, rval;
997 if (TREE_CODE (field) != FIELD_DECL
998 || DECL_ARTIFICIAL (field))
1001 mem_type = strip_array_types (TREE_TYPE (field));
1005 if (CP_TYPE_CONST_P (mem_type) && !CLASS_TYPE_P (mem_type))
1008 error ("non-static const member %q#D, can%'t use default "
1009 "assignment operator", field);
1011 else if (TREE_CODE (mem_type) == REFERENCE_TYPE)
1014 error ("non-static reference member %q#D, can%'t use "
1015 "default assignment operator", field);
1020 if (bad && deleted_p)
1023 else if (sfk == sfk_constructor)
1026 if (CP_TYPE_CONST_P (mem_type)
1027 && (!CLASS_TYPE_P (mem_type)
1028 || !type_has_user_provided_default_constructor (mem_type)))
1031 error ("uninitialized non-static const member %q#D",
1034 else if (TREE_CODE (mem_type) == REFERENCE_TYPE)
1037 error ("uninitialized non-static reference member %q#D",
1043 if (bad && deleted_p)
1046 /* For an implicitly-defined default constructor to be constexpr,
1047 every member must have a user-provided default constructor. */
1048 /* FIXME will need adjustment for non-static data member
1050 if (constexpr_p && !CLASS_TYPE_P (mem_type))
1052 *constexpr_p = false;
1054 inform (0, "defaulted default constructor does not "
1055 "initialize %q+#D", field);
1059 if (!CLASS_TYPE_P (mem_type))
1062 if (ANON_AGGR_TYPE_P (mem_type))
1064 walk_field_subobs (TYPE_FIELDS (mem_type), fnname, sfk, quals,
1065 copy_arg_p, move_p, assign_p, spec_p, trivial_p,
1066 deleted_p, constexpr_p, msg, flags, complain);
1072 int mem_quals = cp_type_quals (mem_type) | quals;
1073 if (DECL_MUTABLE_P (field))
1074 mem_quals &= ~TYPE_QUAL_CONST;
1075 argtype = build_stub_type (mem_type, mem_quals, move_p);
1078 argtype = NULL_TREE;
1080 rval = locate_fn_flags (mem_type, fnname, argtype, flags, complain);
1082 process_subob_fn (rval, move_p, spec_p, trivial_p, deleted_p,
1083 constexpr_p, msg, field);
1087 /* The caller wants to generate an implicit declaration of SFK for CTYPE
1088 which is const if relevant and CONST_P is set. If spec_p, trivial_p and
1089 deleted_p are non-null, set their referent appropriately. If diag is
1090 true, we're either being called from maybe_explain_implicit_delete to
1091 give errors, or if constexpr_p is non-null, from
1092 explain_invalid_constexpr_fn. */
1095 synthesized_method_walk (tree ctype, special_function_kind sfk, bool const_p,
1096 tree *spec_p, bool *trivial_p, bool *deleted_p,
1097 bool *constexpr_p, bool diag)
1099 tree binfo, base_binfo, scope, fnname, rval, argtype;
1100 bool move_p, copy_arg_p, assign_p, expected_trivial, check_vdtor;
1101 VEC(tree,gc) *vbases;
1102 int i, quals, flags;
1103 tsubst_flags_t complain;
1108 *spec_p = (cxx_dialect >= cxx0x ? noexcept_true_spec : empty_except_spec);
1112 /* "The closure type associated with a lambda-expression has a deleted
1113 default constructor and a deleted copy assignment operator."
1114 This is diagnosed in maybe_explain_implicit_delete. */
1115 if (LAMBDA_TYPE_P (ctype)
1116 && (sfk == sfk_constructor
1117 || sfk == sfk_copy_assignment))
1128 check_vdtor = false;
1131 case sfk_move_assignment:
1132 case sfk_copy_assignment:
1134 fnname = ansi_assopname (NOP_EXPR);
1137 case sfk_destructor:
1139 /* The synthesized method will call base dtors, but check complete
1140 here to avoid having to deal with VTT. */
1141 fnname = complete_dtor_identifier;
1144 case sfk_constructor:
1145 case sfk_move_constructor:
1146 case sfk_copy_constructor:
1148 fnname = complete_ctor_identifier;
1155 /* If that user-written default constructor would satisfy the
1156 requirements of a constexpr constructor (7.1.5), the
1157 implicitly-defined default constructor is constexpr. */
1159 *constexpr_p = ctor_p;
1164 case sfk_constructor:
1165 case sfk_destructor:
1169 case sfk_move_constructor:
1170 case sfk_move_assignment:
1172 case sfk_copy_constructor:
1173 case sfk_copy_assignment:
1181 expected_trivial = type_has_trivial_fn (ctype, sfk);
1183 *trivial_p = expected_trivial;
1185 /* The TYPE_HAS_COMPLEX_* flags tell us about constraints from base
1186 class versions and other properties of the type. But a subobject
1187 class can be trivially copyable and yet have overload resolution
1188 choose a template constructor for initialization, depending on
1189 rvalueness and cv-quals. So we can't exit early for copy/move
1190 methods in C++0x. The same considerations apply in C++98/03, but
1191 there the definition of triviality does not consider overload
1192 resolution, so a constructor can be trivial even if it would otherwise
1193 call a non-trivial constructor. */
1194 if (expected_trivial
1196 && (!copy_arg_p || cxx_dialect < cxx0x))
1198 if (constexpr_p && sfk == sfk_constructor)
1199 *constexpr_p = synthesized_default_constructor_is_constexpr (ctype);
1203 ++cp_unevaluated_operand;
1204 ++c_inhibit_evaluation_warnings;
1206 scope = push_scope (ctype);
1210 flags = LOOKUP_NORMAL|LOOKUP_SPECULATIVE|LOOKUP_DEFAULTED;
1211 complain = tf_warning_or_error;
1215 flags = LOOKUP_PROTECT|LOOKUP_SPECULATIVE|LOOKUP_DEFAULTED;
1220 quals = TYPE_QUAL_CONST;
1222 quals = TYPE_UNQUALIFIED;
1223 argtype = NULL_TREE;
1228 msg = ("base %qT does not have a move assignment operator or trivial "
1229 "copy assignment operator");
1231 msg = ("base %qT does not have a move constructor or trivial "
1232 "copy constructor");
1234 for (binfo = TYPE_BINFO (ctype), i = 0;
1235 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
1237 tree basetype = BINFO_TYPE (base_binfo);
1239 argtype = build_stub_type (basetype, quals, move_p);
1240 rval = locate_fn_flags (base_binfo, fnname, argtype, flags, complain);
1242 process_subob_fn (rval, move_p, spec_p, trivial_p, deleted_p,
1243 constexpr_p, msg, basetype);
1244 if (ctor_p && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype))
1246 /* In a constructor we also need to check the subobject
1247 destructors for cleanup of partially constructed objects. */
1248 rval = locate_fn_flags (base_binfo, complete_dtor_identifier,
1249 NULL_TREE, flags, complain);
1250 /* Note that we don't pass down trivial_p; the subobject
1251 destructors don't affect triviality of the constructor. */
1252 process_subob_fn (rval, false, spec_p, NULL,
1253 deleted_p, NULL, NULL,
1257 if (check_vdtor && type_has_virtual_destructor (basetype))
1259 rval = locate_fn_flags (ctype, ansi_opname (DELETE_EXPR),
1260 ptr_type_node, flags, complain);
1261 /* Unlike for base ctor/op=/dtor, for operator delete it's fine
1262 to have a null rval (no class-specific op delete). */
1263 if (rval && rval == error_mark_node && deleted_p)
1265 check_vdtor = false;
1269 vbases = CLASSTYPE_VBASECLASSES (ctype);
1270 if (vbases && assign_p && move_p)
1272 /* Should the spec be changed to allow vbases that only occur once? */
1274 error ("%qT has virtual bases, default move assignment operator "
1275 "cannot be generated", ctype);
1282 msg = ("virtual base %qT does not have a move constructor "
1283 "or trivial copy constructor");
1284 if (vbases && constexpr_p)
1285 *constexpr_p = false;
1286 FOR_EACH_VEC_ELT (tree, vbases, i, base_binfo)
1288 tree basetype = BINFO_TYPE (base_binfo);
1290 argtype = build_stub_type (basetype, quals, move_p);
1291 rval = locate_fn_flags (base_binfo, fnname, argtype, flags, complain);
1293 process_subob_fn (rval, move_p, spec_p, trivial_p, deleted_p,
1294 constexpr_p, msg, basetype);
1295 if (ctor_p && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype))
1297 rval = locate_fn_flags (base_binfo, complete_dtor_identifier,
1298 NULL_TREE, flags, complain);
1299 process_subob_fn (rval, false, spec_p, NULL,
1300 deleted_p, NULL, NULL,
1306 /* Leave msg null. */;
1308 msg = ("non-static data member %qD does not have a move "
1309 "assignment operator or trivial copy assignment operator");
1311 msg = ("non-static data member %qD does not have a move "
1312 "constructor or trivial copy constructor");
1313 walk_field_subobs (TYPE_FIELDS (ctype), fnname, sfk, quals,
1314 copy_arg_p, move_p, assign_p, spec_p, trivial_p,
1315 deleted_p, constexpr_p, msg, flags, complain);
1317 walk_field_subobs (TYPE_FIELDS (ctype), complete_dtor_identifier,
1318 sfk_destructor, TYPE_UNQUALIFIED, false,
1319 false, false, spec_p, NULL,
1321 NULL, flags, complain);
1325 --cp_unevaluated_operand;
1326 --c_inhibit_evaluation_warnings;
1329 /* DECL is a deleted function. If it's implicitly deleted, explain why and
1330 return true; else return false. */
1333 maybe_explain_implicit_delete (tree decl)
1335 /* If decl is a clone, get the primary variant. */
1336 decl = DECL_ORIGIN (decl);
1337 gcc_assert (DECL_DELETED_FN (decl));
1338 if (DECL_DEFAULTED_FN (decl))
1340 /* Not marked GTY; it doesn't need to be GC'd or written to PCH. */
1341 static struct pointer_set_t *explained;
1343 special_function_kind sfk;
1349 explained = pointer_set_create ();
1350 if (pointer_set_insert (explained, decl))
1353 sfk = special_function_p (decl);
1354 ctype = DECL_CONTEXT (decl);
1355 loc = input_location;
1356 input_location = DECL_SOURCE_LOCATION (decl);
1359 if (LAMBDA_TYPE_P (ctype))
1362 if (sfk == sfk_constructor)
1363 error ("a lambda closure type has a deleted default constructor");
1364 else if (sfk == sfk_copy_assignment)
1365 error ("a lambda closure type has a deleted copy assignment operator");
1371 tree parm_type = TREE_VALUE (FUNCTION_FIRST_USER_PARMTYPE (decl));
1372 bool const_p = CP_TYPE_CONST_P (non_reference (parm_type));
1373 tree scope = push_scope (ctype);
1374 error ("%qD is implicitly deleted because the default "
1375 "definition would be ill-formed:", decl);
1377 synthesized_method_walk (ctype, sfk, const_p,
1378 NULL, NULL, NULL, NULL, true);
1381 input_location = loc;
1387 /* DECL is a defaulted function which was declared constexpr. Explain why
1388 it can't be constexpr. */
1391 explain_implicit_non_constexpr (tree decl)
1393 tree parm_type = TREE_VALUE (FUNCTION_FIRST_USER_PARMTYPE (decl));
1394 bool const_p = CP_TYPE_CONST_P (non_reference (parm_type));
1396 synthesized_method_walk (DECL_CLASS_CONTEXT (decl),
1397 special_function_p (decl), const_p,
1398 NULL, NULL, NULL, &dummy, true);
1401 /* Implicitly declare the special function indicated by KIND, as a
1402 member of TYPE. For copy constructors and assignment operators,
1403 CONST_P indicates whether these functions should take a const
1404 reference argument or a non-const reference. Returns the
1405 FUNCTION_DECL for the implicitly declared function. */
1408 implicitly_declare_fn (special_function_kind kind, tree type, bool const_p)
1411 tree parameter_types = void_list_node;
1414 tree raises = empty_except_spec;
1415 tree rhs_parm_type = NULL_TREE;
1418 HOST_WIDE_INT saved_processing_template_decl;
1423 /* Because we create declarations for implicitly declared functions
1424 lazily, we may be creating the declaration for a member of TYPE
1425 while in some completely different context. However, TYPE will
1426 never be a dependent class (because we never want to do lookups
1427 for implicitly defined functions in a dependent class).
1428 Furthermore, we must set PROCESSING_TEMPLATE_DECL to zero here
1429 because we only create clones for constructors and destructors
1430 when not in a template. */
1431 gcc_assert (!dependent_type_p (type));
1432 saved_processing_template_decl = processing_template_decl;
1433 processing_template_decl = 0;
1435 type = TYPE_MAIN_VARIANT (type);
1437 if (targetm.cxx.cdtor_returns_this () && !TYPE_FOR_JAVA (type))
1439 if (kind == sfk_destructor)
1440 /* See comment in check_special_function_return_type. */
1441 return_type = build_pointer_type (void_type_node);
1443 return_type = build_pointer_type (type);
1446 return_type = void_type_node;
1450 case sfk_destructor:
1452 name = constructor_name (type);
1455 case sfk_constructor:
1456 /* Default constructor. */
1457 name = constructor_name (type);
1460 case sfk_copy_constructor:
1461 case sfk_copy_assignment:
1462 case sfk_move_constructor:
1463 case sfk_move_assignment:
1466 if (kind == sfk_copy_assignment
1467 || kind == sfk_move_assignment)
1469 return_type = build_reference_type (type);
1470 name = ansi_assopname (NOP_EXPR);
1473 name = constructor_name (type);
1476 rhs_parm_type = cp_build_qualified_type (type, TYPE_QUAL_CONST);
1478 rhs_parm_type = type;
1479 move_p = (kind == sfk_move_assignment
1480 || kind == sfk_move_constructor);
1481 rhs_parm_type = cp_build_reference_type (rhs_parm_type, move_p);
1483 parameter_types = tree_cons (NULL_TREE, rhs_parm_type, parameter_types);
1490 synthesized_method_walk (type, kind, const_p, &raises, &trivial_p,
1491 &deleted_p, &constexpr_p, false);
1492 /* Don't bother marking a deleted constructor as constexpr. */
1494 constexpr_p = false;
1495 /* A trivial copy/move constructor is also a constexpr constructor. */
1496 else if (trivial_p && cxx_dialect >= cxx0x
1497 && (kind == sfk_copy_constructor
1498 || kind == sfk_move_constructor))
1499 gcc_assert (constexpr_p);
1501 if (!trivial_p && type_has_trivial_fn (type, kind))
1502 type_set_nontrivial_flag (type, kind);
1504 /* Create the function. */
1505 fn_type = build_method_type_directly (type, return_type, parameter_types);
1507 fn_type = build_exception_variant (fn_type, raises);
1508 fn = build_lang_decl (FUNCTION_DECL, name, fn_type);
1509 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (TYPE_NAME (type));
1510 if (kind == sfk_constructor || kind == sfk_copy_constructor
1511 || kind == sfk_move_constructor)
1512 DECL_CONSTRUCTOR_P (fn) = 1;
1513 else if (kind == sfk_destructor)
1514 DECL_DESTRUCTOR_P (fn) = 1;
1517 DECL_ASSIGNMENT_OPERATOR_P (fn) = 1;
1518 SET_OVERLOADED_OPERATOR_CODE (fn, NOP_EXPR);
1521 /* If pointers to member functions use the least significant bit to
1522 indicate whether a function is virtual, ensure a pointer
1523 to this function will have that bit clear. */
1524 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_pfn
1525 && DECL_ALIGN (fn) < 2 * BITS_PER_UNIT)
1526 DECL_ALIGN (fn) = 2 * BITS_PER_UNIT;
1528 /* Create the explicit arguments. */
1531 /* Note that this parameter is *not* marked DECL_ARTIFICIAL; we
1532 want its type to be included in the mangled function
1534 tree decl = cp_build_parm_decl (NULL_TREE, rhs_parm_type);
1535 TREE_READONLY (decl) = 1;
1536 retrofit_lang_decl (decl);
1537 DECL_PARM_INDEX (decl) = DECL_PARM_LEVEL (decl) = 1;
1538 DECL_ARGUMENTS (fn) = decl;
1540 /* Add the "this" parameter. */
1541 this_parm = build_this_parm (fn_type, TYPE_UNQUALIFIED);
1542 DECL_CHAIN (this_parm) = DECL_ARGUMENTS (fn);
1543 DECL_ARGUMENTS (fn) = this_parm;
1545 grokclassfn (type, fn, kind == sfk_destructor ? DTOR_FLAG : NO_SPECIAL);
1546 set_linkage_according_to_type (type, fn);
1547 rest_of_decl_compilation (fn, toplevel_bindings_p (), at_eof);
1548 DECL_IN_AGGR_P (fn) = 1;
1549 DECL_ARTIFICIAL (fn) = 1;
1550 DECL_DEFAULTED_FN (fn) = 1;
1551 if (cxx_dialect >= cxx0x)
1553 DECL_DELETED_FN (fn) = deleted_p;
1554 DECL_DECLARED_CONSTEXPR_P (fn) = constexpr_p;
1556 DECL_NOT_REALLY_EXTERN (fn) = 1;
1557 DECL_DECLARED_INLINE_P (fn) = 1;
1558 gcc_assert (!TREE_USED (fn));
1560 /* Restore PROCESSING_TEMPLATE_DECL. */
1561 processing_template_decl = saved_processing_template_decl;
1566 /* Gives any errors about defaulted functions which need to be deferred
1567 until the containing class is complete. */
1570 defaulted_late_check (tree fn)
1572 /* Complain about invalid signature for defaulted fn. */
1573 tree ctx = DECL_CONTEXT (fn);
1574 special_function_kind kind = special_function_p (fn);
1575 bool fn_const_p = (copy_fn_p (fn) == 2);
1576 tree implicit_fn = implicitly_declare_fn (kind, ctx, fn_const_p);
1578 if (!same_type_p (TREE_TYPE (TREE_TYPE (fn)),
1579 TREE_TYPE (TREE_TYPE (implicit_fn)))
1580 || !compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1581 TYPE_ARG_TYPES (TREE_TYPE (implicit_fn))))
1583 error ("defaulted declaration %q+D", fn);
1584 error_at (DECL_SOURCE_LOCATION (fn),
1585 "does not match expected signature %qD", implicit_fn);
1588 /* 8.4.2/2: If it is explicitly defaulted on its first declaration, it is
1589 implicitly considered to have the same exception-specification as if
1590 it had been implicitly declared. */
1591 if (DECL_DEFAULTED_IN_CLASS_P (fn))
1593 tree eh_spec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (implicit_fn));
1594 if (TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn)))
1596 maybe_instantiate_noexcept (fn);
1597 if (!comp_except_specs (TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn)),
1598 eh_spec, ce_normal))
1599 error ("function %q+D defaulted on its first declaration "
1600 "with an exception-specification that differs from "
1601 "the implicit declaration %q#D", fn, implicit_fn);
1603 TREE_TYPE (fn) = build_exception_variant (TREE_TYPE (fn), eh_spec);
1604 if (DECL_DECLARED_CONSTEXPR_P (implicit_fn))
1606 /* Hmm...should we do this for out-of-class too? Should it be OK to
1607 add constexpr later like inline, rather than requiring
1608 declarations to match? */
1609 DECL_DECLARED_CONSTEXPR_P (fn) = true;
1610 if (kind == sfk_constructor)
1611 TYPE_HAS_CONSTEXPR_CTOR (ctx) = true;
1615 if (!DECL_DECLARED_CONSTEXPR_P (implicit_fn)
1616 && DECL_DECLARED_CONSTEXPR_P (fn))
1618 if (!CLASSTYPE_TEMPLATE_INSTANTIATION (ctx))
1620 error ("explicitly defaulted function %q+D cannot be declared "
1621 "as constexpr because the implicit declaration is not "
1623 explain_implicit_non_constexpr (fn);
1625 DECL_DECLARED_CONSTEXPR_P (fn) = false;
1628 if (DECL_DELETED_FN (implicit_fn))
1629 DECL_DELETED_FN (fn) = 1;
1632 /* Returns true iff FN can be explicitly defaulted, and gives any
1633 errors if defaulting FN is ill-formed. */
1636 defaultable_fn_check (tree fn)
1638 special_function_kind kind = sfk_none;
1640 if (template_parm_scope_p ())
1642 error ("a template cannot be defaulted");
1646 if (DECL_CONSTRUCTOR_P (fn))
1648 if (FUNCTION_FIRST_USER_PARMTYPE (fn) == void_list_node)
1649 kind = sfk_constructor;
1650 else if (copy_fn_p (fn) > 0
1651 && (TREE_CHAIN (FUNCTION_FIRST_USER_PARMTYPE (fn))
1653 kind = sfk_copy_constructor;
1654 else if (move_fn_p (fn))
1655 kind = sfk_move_constructor;
1657 else if (DECL_DESTRUCTOR_P (fn))
1658 kind = sfk_destructor;
1659 else if (DECL_ASSIGNMENT_OPERATOR_P (fn)
1660 && DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR)
1663 kind = sfk_copy_assignment;
1664 else if (move_fn_p (fn))
1665 kind = sfk_move_assignment;
1668 if (kind == sfk_none)
1670 error ("%qD cannot be defaulted", fn);
1675 tree t = FUNCTION_FIRST_USER_PARMTYPE (fn);
1676 for (; t && t != void_list_node; t = TREE_CHAIN (t))
1677 if (TREE_PURPOSE (t))
1679 error ("defaulted function %q+D with default argument", fn);
1682 if (TYPE_BEING_DEFINED (DECL_CONTEXT (fn)))
1683 /* Defer checking. */;
1684 else if (!processing_template_decl)
1685 defaulted_late_check (fn);
1691 /* Add an implicit declaration to TYPE for the kind of function
1692 indicated by SFK. Return the FUNCTION_DECL for the new implicit
1696 lazily_declare_fn (special_function_kind sfk, tree type)
1699 /* Whether or not the argument has a const reference type. */
1700 bool const_p = false;
1704 case sfk_constructor:
1705 CLASSTYPE_LAZY_DEFAULT_CTOR (type) = 0;
1707 case sfk_copy_constructor:
1708 const_p = TYPE_HAS_CONST_COPY_CTOR (type);
1709 CLASSTYPE_LAZY_COPY_CTOR (type) = 0;
1711 case sfk_move_constructor:
1712 CLASSTYPE_LAZY_MOVE_CTOR (type) = 0;
1714 case sfk_copy_assignment:
1715 const_p = TYPE_HAS_CONST_COPY_ASSIGN (type);
1716 CLASSTYPE_LAZY_COPY_ASSIGN (type) = 0;
1718 case sfk_move_assignment:
1719 CLASSTYPE_LAZY_MOVE_ASSIGN (type) = 0;
1721 case sfk_destructor:
1722 CLASSTYPE_LAZY_DESTRUCTOR (type) = 0;
1728 /* Declare the function. */
1729 fn = implicitly_declare_fn (sfk, type, const_p);
1731 /* For move variants, rather than declare them as deleted we just
1732 don't declare them at all. */
1733 if (DECL_DELETED_FN (fn)
1734 && (sfk == sfk_move_constructor
1735 || sfk == sfk_move_assignment))
1738 /* A destructor may be virtual. */
1739 if (sfk == sfk_destructor
1740 || sfk == sfk_move_assignment
1741 || sfk == sfk_copy_assignment)
1742 check_for_override (fn, type);
1743 /* Add it to CLASSTYPE_METHOD_VEC. */
1744 add_method (type, fn, NULL_TREE);
1745 /* Add it to TYPE_METHODS. */
1746 if (sfk == sfk_destructor
1747 && DECL_VIRTUAL_P (fn)
1748 && abi_version_at_least (2))
1749 /* The ABI requires that a virtual destructor go at the end of the
1751 TYPE_METHODS (type) = chainon (TYPE_METHODS (type), fn);
1754 /* G++ 3.2 put the implicit destructor at the *beginning* of the
1755 TYPE_METHODS list, which cause the destructor to be emitted
1756 in an incorrect location in the vtable. */
1757 if (warn_abi && sfk == sfk_destructor && DECL_VIRTUAL_P (fn))
1758 warning (OPT_Wabi, "vtable layout for class %qT may not be ABI-compliant"
1759 "and may change in a future version of GCC due to "
1760 "implicit virtual destructor",
1762 DECL_CHAIN (fn) = TYPE_METHODS (type);
1763 TYPE_METHODS (type) = fn;
1765 maybe_add_class_template_decl_list (type, fn, /*friend_p=*/0);
1766 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn)
1767 || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn))
1768 /* Create appropriate clones. */
1769 clone_function_decl (fn, /*update_method_vec=*/true);
1774 /* Given a FUNCTION_DECL FN and a chain LIST, skip as many elements of LIST
1775 as there are artificial parms in FN. */
1778 skip_artificial_parms_for (const_tree fn, tree list)
1780 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
1781 list = TREE_CHAIN (list);
1785 if (DECL_HAS_IN_CHARGE_PARM_P (fn))
1786 list = TREE_CHAIN (list);
1787 if (DECL_HAS_VTT_PARM_P (fn))
1788 list = TREE_CHAIN (list);
1792 /* Given a FUNCTION_DECL FN and a chain LIST, return the number of
1793 artificial parms in FN. */
1796 num_artificial_parms_for (const_tree fn)
1800 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
1805 if (DECL_HAS_IN_CHARGE_PARM_P (fn))
1807 if (DECL_HAS_VTT_PARM_P (fn))
1813 #include "gt-cp-method.h"