1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
37 #include "tree-inline.h"
46 /* The type of functions taking a tree, and some additional data, and
48 typedef int (*tree_fn_t) (tree, void*);
50 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
51 instantiations have been deferred, either because their definitions
52 were not yet available, or because we were putting off doing the work.
53 The TREE_PURPOSE of each entry is either a DECL (for a function or
54 static data member), or a TYPE (for a class) indicating what we are
55 hoping to instantiate. The TREE_VALUE is not used. */
56 static GTY(()) tree pending_templates;
57 static GTY(()) tree last_pending_template;
59 int processing_template_parmlist;
60 static int template_header_count;
62 static GTY(()) tree saved_trees;
63 static GTY(()) varray_type inline_parm_levels;
64 static size_t inline_parm_levels_used;
66 static GTY(()) tree current_tinst_level;
68 static GTY(()) tree saved_access_scope;
70 /* A map from local variable declarations in the body of the template
71 presently being instantiated to the corresponding instantiated
73 static htab_t local_specializations;
75 #define UNIFY_ALLOW_NONE 0
76 #define UNIFY_ALLOW_MORE_CV_QUAL 1
77 #define UNIFY_ALLOW_LESS_CV_QUAL 2
78 #define UNIFY_ALLOW_DERIVED 4
79 #define UNIFY_ALLOW_INTEGER 8
80 #define UNIFY_ALLOW_OUTER_LEVEL 16
81 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
82 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
83 #define UNIFY_ALLOW_MAX_CORRECTION 128
85 #define GTB_VIA_VIRTUAL 1 /* The base class we are examining is
86 virtual, or a base class of a virtual
88 #define GTB_IGNORE_TYPE 2 /* We don't need to try to unify the current
89 type with the desired type. */
91 static void push_access_scope (tree);
92 static void pop_access_scope (tree);
93 static int resolve_overloaded_unification (tree, tree, tree, tree,
94 unification_kind_t, int);
95 static int try_one_overload (tree, tree, tree, tree, tree,
96 unification_kind_t, int, bool);
97 static int unify (tree, tree, tree, tree, int);
98 static void add_pending_template (tree);
99 static void reopen_tinst_level (tree);
100 static tree classtype_mangled_name (tree);
101 static char* mangle_class_name_for_template (const char *, tree, tree);
102 static tree tsubst_initializer_list (tree, tree);
103 static tree get_class_bindings (tree, tree, tree);
104 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
105 static void tsubst_enum (tree, tree, tree);
106 static tree add_to_template_args (tree, tree);
107 static tree add_outermost_template_args (tree, tree);
108 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
109 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
110 static int type_unification_real (tree, tree, tree, tree,
111 int, unification_kind_t, int, int);
112 static void note_template_header (int);
113 static tree convert_nontype_argument (tree, tree);
114 static tree convert_template_argument (tree, tree, tree,
115 tsubst_flags_t, int, tree);
116 static tree get_bindings_overload (tree, tree, tree);
117 static int for_each_template_parm (tree, tree_fn_t, void*, htab_t);
118 static tree build_template_parm_index (int, int, int, tree, tree);
119 static int inline_needs_template_parms (tree);
120 static void push_inline_template_parms_recursive (tree, int);
121 static tree retrieve_specialization (tree, tree);
122 static tree retrieve_local_specialization (tree);
123 static tree register_specialization (tree, tree, tree);
124 static void register_local_specialization (tree, tree);
125 static tree reduce_template_parm_level (tree, tree, int);
126 static tree build_template_decl (tree, tree);
127 static int mark_template_parm (tree, void *);
128 static int template_parm_this_level_p (tree, void *);
129 static tree tsubst_friend_function (tree, tree);
130 static tree tsubst_friend_class (tree, tree);
131 static int can_complete_type_without_circularity (tree);
132 static tree get_bindings (tree, tree, tree);
133 static tree get_bindings_real (tree, tree, tree, int, int, int);
134 static int template_decl_level (tree);
135 static int check_cv_quals_for_unify (int, tree, tree);
136 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
137 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
138 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
139 static void regenerate_decl_from_template (tree, tree);
140 static tree most_specialized (tree, tree, tree);
141 static tree most_specialized_class (tree, tree);
142 static int template_class_depth_real (tree, int);
143 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
144 static tree tsubst_decl (tree, tree, tree, tsubst_flags_t);
145 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
146 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
147 static void check_specialization_scope (void);
148 static tree process_partial_specialization (tree);
149 static void set_current_access_from_decl (tree);
150 static void check_default_tmpl_args (tree, tree, int, int);
151 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
152 static tree get_template_base_recursive (tree, tree, tree, tree, tree, int);
153 static tree get_template_base (tree, tree, tree, tree);
154 static int verify_class_unification (tree, tree, tree);
155 static tree try_class_unification (tree, tree, tree, tree);
156 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
158 static tree determine_specialization (tree, tree, tree *, int);
159 static int template_args_equal (tree, tree);
160 static void tsubst_default_arguments (tree);
161 static tree for_each_template_parm_r (tree *, int *, void *);
162 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
163 static void copy_default_args_to_explicit_spec (tree);
164 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
165 static int eq_local_specializations (const void *, const void *);
166 static bool dependent_type_p_r (tree);
167 static tree tsubst (tree, tree, tsubst_flags_t, tree);
168 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
169 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
171 /* Make the current scope suitable for access checking when we are
172 processing T. T can be FUNCTION_DECL for instantiated function
173 template, or VAR_DECL for static member variable (need by
174 instantiate_decl). */
177 push_access_scope (tree t)
179 my_friendly_assert (TREE_CODE (t) == FUNCTION_DECL
180 || TREE_CODE (t) == VAR_DECL,
183 if (DECL_CLASS_SCOPE_P (t))
184 push_nested_class (DECL_CONTEXT (t));
186 push_to_top_level ();
188 if (TREE_CODE (t) == FUNCTION_DECL)
190 saved_access_scope = tree_cons
191 (NULL_TREE, current_function_decl, saved_access_scope);
192 current_function_decl = t;
196 /* Restore the scope set up by push_access_scope. T is the node we
200 pop_access_scope (tree t)
202 if (TREE_CODE (t) == FUNCTION_DECL)
204 current_function_decl = TREE_VALUE (saved_access_scope);
205 saved_access_scope = TREE_CHAIN (saved_access_scope);
208 if (DECL_CLASS_SCOPE_P (t))
211 pop_from_top_level ();
214 /* Do any processing required when DECL (a member template
215 declaration) is finished. Returns the TEMPLATE_DECL corresponding
216 to DECL, unless it is a specialization, in which case the DECL
217 itself is returned. */
220 finish_member_template_decl (tree decl)
222 if (decl == error_mark_node)
223 return error_mark_node;
225 my_friendly_assert (DECL_P (decl), 20020812);
227 if (TREE_CODE (decl) == TYPE_DECL)
231 type = TREE_TYPE (decl);
232 if (IS_AGGR_TYPE (type)
233 && CLASSTYPE_TEMPLATE_INFO (type)
234 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
236 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
237 check_member_template (tmpl);
242 else if (TREE_CODE (decl) == FIELD_DECL)
243 error ("data member `%D' cannot be a member template", decl);
244 else if (DECL_TEMPLATE_INFO (decl))
246 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
248 check_member_template (DECL_TI_TEMPLATE (decl));
249 return DECL_TI_TEMPLATE (decl);
255 error ("invalid member template declaration `%D'", decl);
257 return error_mark_node;
260 /* Returns the template nesting level of the indicated class TYPE.
270 A<T>::B<U> has depth two, while A<T> has depth one.
271 Both A<T>::B<int> and A<int>::B<U> have depth one, if
272 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
275 This function is guaranteed to return 0 if passed NULL_TREE so
276 that, for example, `template_class_depth (current_class_type)' is
280 template_class_depth_real (tree type, int count_specializations)
285 type && TREE_CODE (type) != NAMESPACE_DECL;
286 type = (TREE_CODE (type) == FUNCTION_DECL)
287 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
289 if (TREE_CODE (type) != FUNCTION_DECL)
291 if (CLASSTYPE_TEMPLATE_INFO (type)
292 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
293 && ((count_specializations
294 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
295 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
300 if (DECL_TEMPLATE_INFO (type)
301 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
302 && ((count_specializations
303 && DECL_TEMPLATE_SPECIALIZATION (type))
304 || uses_template_parms (DECL_TI_ARGS (type))))
312 /* Returns the template nesting level of the indicated class TYPE.
313 Like template_class_depth_real, but instantiations do not count in
317 template_class_depth (tree type)
319 return template_class_depth_real (type, /*count_specializations=*/0);
322 /* Returns 1 if processing DECL as part of do_pending_inlines
323 needs us to push template parms. */
326 inline_needs_template_parms (tree decl)
328 if (! DECL_TEMPLATE_INFO (decl))
331 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
332 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
335 /* Subroutine of maybe_begin_member_template_processing.
336 Push the template parms in PARMS, starting from LEVELS steps into the
337 chain, and ending at the beginning, since template parms are listed
341 push_inline_template_parms_recursive (tree parmlist, int levels)
343 tree parms = TREE_VALUE (parmlist);
347 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
349 ++processing_template_decl;
350 current_template_parms
351 = tree_cons (size_int (processing_template_decl),
352 parms, current_template_parms);
353 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
355 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
357 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
359 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
360 my_friendly_assert (DECL_P (parm), 0);
362 switch (TREE_CODE (parm))
371 /* Make a CONST_DECL as is done in process_template_parm.
372 It is ugly that we recreate this here; the original
373 version built in process_template_parm is no longer
375 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
377 DECL_ARTIFICIAL (decl) = 1;
378 TREE_CONSTANT (decl) = TREE_READONLY (decl) = 1;
379 DECL_INITIAL (decl) = DECL_INITIAL (parm);
380 SET_DECL_TEMPLATE_PARM_P (decl);
391 /* Restore the template parameter context for a member template or
392 a friend template defined in a class definition. */
395 maybe_begin_member_template_processing (tree decl)
400 if (inline_needs_template_parms (decl))
402 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
403 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
405 if (DECL_TEMPLATE_SPECIALIZATION (decl))
408 parms = TREE_CHAIN (parms);
411 push_inline_template_parms_recursive (parms, levels);
414 /* Remember how many levels of template parameters we pushed so that
415 we can pop them later. */
416 if (!inline_parm_levels)
417 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
418 if (inline_parm_levels_used == inline_parm_levels->num_elements)
419 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
420 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
421 ++inline_parm_levels_used;
424 /* Undo the effects of begin_member_template_processing. */
427 maybe_end_member_template_processing (void)
431 if (!inline_parm_levels_used)
434 --inline_parm_levels_used;
436 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
439 --processing_template_decl;
440 current_template_parms = TREE_CHAIN (current_template_parms);
445 /* Returns nonzero iff T is a member template function. We must be
448 template <class T> class C { void f(); }
450 Here, f is a template function, and a member, but not a member
451 template. This function does not concern itself with the origin of
452 T, only its present state. So if we have
454 template <class T> class C { template <class U> void f(U); }
456 then neither C<int>::f<char> nor C<T>::f<double> is considered
457 to be a member template. But, `template <class U> void
458 C<int>::f(U)' is considered a member template. */
461 is_member_template (tree t)
463 if (!DECL_FUNCTION_TEMPLATE_P (t))
464 /* Anything that isn't a function or a template function is
465 certainly not a member template. */
468 /* A local class can't have member templates. */
469 if (decl_function_context (t))
472 return (DECL_FUNCTION_MEMBER_P (DECL_TEMPLATE_RESULT (t))
473 /* If there are more levels of template parameters than
474 there are template classes surrounding the declaration,
475 then we have a member template. */
476 && (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
477 template_class_depth (DECL_CONTEXT (t))));
481 /* Returns nonzero iff T is a member template class. See
482 is_member_template for a description of what precisely constitutes
483 a member template. */
486 is_member_template_class (tree t)
488 if (!DECL_CLASS_TEMPLATE_P (t))
489 /* Anything that isn't a class template, is certainly not a member
493 if (!DECL_CLASS_SCOPE_P (t))
494 /* Anything whose context isn't a class type is surely not a
498 /* If there are more levels of template parameters than there are
499 template classes surrounding the declaration, then we have a
501 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
502 template_class_depth (DECL_CONTEXT (t)));
506 /* Return a new template argument vector which contains all of ARGS,
507 but has as its innermost set of arguments the EXTRA_ARGS. */
510 add_to_template_args (tree args, tree extra_args)
517 extra_depth = TMPL_ARGS_DEPTH (extra_args);
518 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
520 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
521 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
523 for (j = 1; j <= extra_depth; ++j, ++i)
524 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
529 /* Like add_to_template_args, but only the outermost ARGS are added to
530 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
531 (EXTRA_ARGS) levels are added. This function is used to combine
532 the template arguments from a partial instantiation with the
533 template arguments used to attain the full instantiation from the
534 partial instantiation. */
537 add_outermost_template_args (tree args, tree extra_args)
541 /* If there are more levels of EXTRA_ARGS than there are ARGS,
542 something very fishy is going on. */
543 my_friendly_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args),
546 /* If *all* the new arguments will be the EXTRA_ARGS, just return
548 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
551 /* For the moment, we make ARGS look like it contains fewer levels. */
552 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
554 new_args = add_to_template_args (args, extra_args);
556 /* Now, we restore ARGS to its full dimensions. */
557 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
562 /* Return the N levels of innermost template arguments from the ARGS. */
565 get_innermost_template_args (tree args, int n)
571 my_friendly_assert (n >= 0, 20000603);
573 /* If N is 1, just return the innermost set of template arguments. */
575 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
577 /* If we're not removing anything, just return the arguments we were
579 extra_levels = TMPL_ARGS_DEPTH (args) - n;
580 my_friendly_assert (extra_levels >= 0, 20000603);
581 if (extra_levels == 0)
584 /* Make a new set of arguments, not containing the outer arguments. */
585 new_args = make_tree_vec (n);
586 for (i = 1; i <= n; ++i)
587 SET_TMPL_ARGS_LEVEL (new_args, i,
588 TMPL_ARGS_LEVEL (args, i + extra_levels));
593 /* We've got a template header coming up; push to a new level for storing
597 begin_template_parm_list (void)
599 /* We use a non-tag-transparent scope here, which causes pushtag to
600 put tags in this scope, rather than in the enclosing class or
601 namespace scope. This is the right thing, since we want
602 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
603 global template class, push_template_decl handles putting the
604 TEMPLATE_DECL into top-level scope. For a nested template class,
607 template <class T> struct S1 {
608 template <class T> struct S2 {};
611 pushtag contains special code to call pushdecl_with_scope on the
612 TEMPLATE_DECL for S2. */
613 begin_scope (sk_template_parms, NULL);
614 ++processing_template_decl;
615 ++processing_template_parmlist;
616 note_template_header (0);
619 /* This routine is called when a specialization is declared. If it is
620 invalid to declare a specialization here, an error is reported. */
623 check_specialization_scope (void)
625 tree scope = current_scope ();
629 An explicit specialization shall be declared in the namespace of
630 which the template is a member, or, for member templates, in the
631 namespace of which the enclosing class or enclosing class
632 template is a member. An explicit specialization of a member
633 function, member class or static data member of a class template
634 shall be declared in the namespace of which the class template
636 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
637 error ("explicit specialization in non-namespace scope `%D'",
642 In an explicit specialization declaration for a member of a class
643 template or a member template that appears in namespace scope,
644 the member template and some of its enclosing class templates may
645 remain unspecialized, except that the declaration shall not
646 explicitly specialize a class member template if its enclosing
647 class templates are not explicitly specialized as well. */
648 if (current_template_parms)
649 error ("enclosing class templates are not explicitly specialized");
652 /* We've just seen template <>. */
655 begin_specialization (void)
657 begin_scope (sk_template_spec, NULL);
658 note_template_header (1);
659 check_specialization_scope ();
662 /* Called at then end of processing a declaration preceded by
666 end_specialization (void)
669 reset_specialization ();
672 /* Any template <>'s that we have seen thus far are not referring to a
673 function specialization. */
676 reset_specialization (void)
678 processing_specialization = 0;
679 template_header_count = 0;
682 /* We've just seen a template header. If SPECIALIZATION is nonzero,
683 it was of the form template <>. */
686 note_template_header (int specialization)
688 processing_specialization = specialization;
689 template_header_count++;
692 /* We're beginning an explicit instantiation. */
695 begin_explicit_instantiation (void)
697 my_friendly_assert (!processing_explicit_instantiation, 20020913);
698 processing_explicit_instantiation = true;
703 end_explicit_instantiation (void)
705 my_friendly_assert(processing_explicit_instantiation, 20020913);
706 processing_explicit_instantiation = false;
709 /* The TYPE is being declared. If it is a template type, that means it
710 is a partial specialization. Do appropriate error-checking. */
713 maybe_process_partial_specialization (tree type)
715 /* TYPE maybe an ERROR_MARK_NODE. */
716 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
718 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
720 /* This is for ordinary explicit specialization and partial
721 specialization of a template class such as:
723 template <> class C<int>;
727 template <class T> class C<T*>;
729 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
731 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
732 && !COMPLETE_TYPE_P (type))
734 tree tpl_ns = decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type));
735 if (is_associated_namespace (current_namespace, tpl_ns))
736 /* Same or super-using namespace. */;
739 pedwarn ("specializing `%#T' in different namespace", type);
740 cp_pedwarn_at (" from definition of `%#D'",
741 CLASSTYPE_TI_TEMPLATE (type));
743 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
744 if (processing_template_decl)
745 push_template_decl (TYPE_MAIN_DECL (type));
747 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
748 error ("specialization of `%T' after instantiation", type);
750 else if (CLASS_TYPE_P (type)
751 && !CLASSTYPE_USE_TEMPLATE (type)
752 && CLASSTYPE_TEMPLATE_INFO (type)
753 && context && CLASS_TYPE_P (context)
754 && CLASSTYPE_TEMPLATE_INFO (context))
756 /* This is for an explicit specialization of member class
757 template according to [temp.expl.spec/18]:
759 template <> template <class U> class C<int>::D;
761 The context `C<int>' must be an implicit instantiation.
762 Otherwise this is just a member class template declared
765 template <> class C<int> { template <class U> class D; };
766 template <> template <class U> class C<int>::D;
768 In the first case, `C<int>::D' is a specialization of `C<T>::D'
769 while in the second case, `C<int>::D' is a primary template
770 and `C<T>::D' may not exist. */
772 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
773 && !COMPLETE_TYPE_P (type))
777 if (current_namespace
778 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
780 pedwarn ("specializing `%#T' in different namespace", type);
781 cp_pedwarn_at (" from definition of `%#D'",
782 CLASSTYPE_TI_TEMPLATE (type));
785 /* Check for invalid specialization after instantiation:
787 template <> template <> class C<int>::D<int>;
788 template <> template <class U> class C<int>::D; */
790 for (t = DECL_TEMPLATE_INSTANTIATIONS
791 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
792 t; t = TREE_CHAIN (t))
793 if (TREE_VALUE (t) != type
794 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
795 error ("specialization `%T' after instantiation `%T'",
796 type, TREE_VALUE (t));
798 /* Mark TYPE as a specialization. And as a result, we only
799 have one level of template argument for the innermost
801 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
802 CLASSTYPE_TI_ARGS (type)
803 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
806 else if (processing_specialization)
807 error ("explicit specialization of non-template `%T'", type);
810 /* Retrieve the specialization (in the sense of [temp.spec] - a
811 specialization is either an instantiation or an explicit
812 specialization) of TMPL for the given template ARGS. If there is
813 no such specialization, return NULL_TREE. The ARGS are a vector of
814 arguments, or a vector of vectors of arguments, in the case of
815 templates with more than one level of parameters. */
818 retrieve_specialization (tree tmpl, tree args)
822 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
824 /* There should be as many levels of arguments as there are
825 levels of parameters. */
826 my_friendly_assert (TMPL_ARGS_DEPTH (args)
827 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
830 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
833 if (comp_template_args (TREE_PURPOSE (s), args))
834 return TREE_VALUE (s);
839 /* Like retrieve_specialization, but for local declarations. */
842 retrieve_local_specialization (tree tmpl)
844 tree spec = htab_find_with_hash (local_specializations, tmpl,
845 htab_hash_pointer (tmpl));
846 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
849 /* Returns nonzero iff DECL is a specialization of TMPL. */
852 is_specialization_of (tree decl, tree tmpl)
856 if (TREE_CODE (decl) == FUNCTION_DECL)
860 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
866 my_friendly_assert (TREE_CODE (decl) == TYPE_DECL, 0);
868 for (t = TREE_TYPE (decl);
870 t = CLASSTYPE_USE_TEMPLATE (t)
871 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
872 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
879 /* Returns nonzero iff DECL is a specialization of friend declaration
880 FRIEND according to [temp.friend]. */
883 is_specialization_of_friend (tree decl, tree friend)
885 bool need_template = true;
888 my_friendly_assert (TREE_CODE (decl) == FUNCTION_DECL, 0);
890 /* For [temp.friend/6] when FRIEND is an ordinary member function
891 of a template class, we want to check if DECL is a specialization
893 if (TREE_CODE (friend) == FUNCTION_DECL
894 && DECL_TEMPLATE_INFO (friend)
895 && !DECL_USE_TEMPLATE (friend))
897 friend = DECL_TI_TEMPLATE (friend);
898 need_template = false;
901 /* There is nothing to do if this is not a template friend. */
902 if (TREE_CODE (friend) != TEMPLATE_DECL)
905 if (is_specialization_of (decl, friend))
909 A member of a class template may be declared to be a friend of a
910 non-template class. In this case, the corresponding member of
911 every specialization of the class template is a friend of the
912 class granting friendship.
914 For example, given a template friend declaration
916 template <class T> friend void A<T>::f();
918 the member function below is considered a friend
920 template <> struct A<int> {
924 For this type of template friend, TEMPLATE_DEPTH below will be
925 nonzero. To determine if DECL is a friend of FRIEND, we first
926 check if the enclosing class is a specialization of another. */
928 template_depth = template_class_depth (DECL_CONTEXT (friend));
930 && DECL_CLASS_SCOPE_P (decl)
931 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
932 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
934 /* Next, we check the members themselves. In order to handle
935 a few tricky cases like
937 template <class T> friend void A<T>::g(T t);
938 template <class T> template <T t> friend void A<T>::h();
940 we need to figure out what ARGS is (corresponding to `T' in above
941 examples) from DECL for later processing. */
943 tree context = DECL_CONTEXT (decl);
944 tree args = NULL_TREE;
945 int current_depth = 0;
946 while (current_depth < template_depth)
948 if (CLASSTYPE_TEMPLATE_INFO (context))
950 if (current_depth == 0)
951 args = TYPE_TI_ARGS (context);
953 args = add_to_template_args (TYPE_TI_ARGS (context), args);
956 context = TYPE_CONTEXT (context);
959 if (TREE_CODE (decl) == FUNCTION_DECL)
964 tree friend_args_type;
967 /* Make sure that both DECL and FRIEND are templates or
969 is_template = DECL_TEMPLATE_INFO (decl)
970 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
971 if (need_template ^ is_template)
973 else if (is_template)
975 /* If both are templates, check template parameter list. */
977 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
979 if (!comp_template_parms
980 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
984 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
987 decl_type = TREE_TYPE (decl);
989 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
991 if (friend_type == error_mark_node)
994 /* Check if return types match. */
995 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
998 /* Check if function parameter types match, ignoring the
1000 friend_args_type = TYPE_ARG_TYPES (friend_type);
1001 decl_args_type = TYPE_ARG_TYPES (decl_type);
1002 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1003 friend_args_type = TREE_CHAIN (friend_args_type);
1004 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1005 decl_args_type = TREE_CHAIN (decl_args_type);
1006 if (compparms (decl_args_type, friend_args_type))
1013 /* Register the specialization SPEC as a specialization of TMPL with
1014 the indicated ARGS. Returns SPEC, or an equivalent prior
1015 declaration, if available. */
1018 register_specialization (tree spec, tree tmpl, tree args)
1022 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
1024 if (TREE_CODE (spec) == FUNCTION_DECL
1025 && uses_template_parms (DECL_TI_ARGS (spec)))
1026 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1027 register it; we want the corresponding TEMPLATE_DECL instead.
1028 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1029 the more obvious `uses_template_parms (spec)' to avoid problems
1030 with default function arguments. In particular, given
1031 something like this:
1033 template <class T> void f(T t1, T t = T())
1035 the default argument expression is not substituted for in an
1036 instantiation unless and until it is actually needed. */
1039 /* There should be as many levels of arguments as there are
1040 levels of parameters. */
1041 my_friendly_assert (TMPL_ARGS_DEPTH (args)
1042 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
1045 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1049 tree fn = TREE_VALUE (s);
1051 /* We can sometimes try to re-register a specialization that we've
1052 already got. In particular, regenerate_decl_from_template
1053 calls duplicate_decls which will update the specialization
1054 list. But, we'll still get called again here anyhow. It's
1055 more convenient to simply allow this than to try to prevent it. */
1058 else if (comp_template_args (TREE_PURPOSE (s), args))
1060 if (DECL_TEMPLATE_SPECIALIZATION (spec))
1062 if (DECL_TEMPLATE_INSTANTIATION (fn))
1065 || DECL_EXPLICIT_INSTANTIATION (fn))
1067 error ("specialization of %D after instantiation",
1073 /* This situation should occur only if the first
1074 specialization is an implicit instantiation,
1075 the second is an explicit specialization, and
1076 the implicit instantiation has not yet been
1077 used. That situation can occur if we have
1078 implicitly instantiated a member function and
1079 then specialized it later.
1081 We can also wind up here if a friend
1082 declaration that looked like an instantiation
1083 turns out to be a specialization:
1085 template <class T> void foo(T);
1086 class S { friend void foo<>(int) };
1087 template <> void foo(int);
1089 We transform the existing DECL in place so that
1090 any pointers to it become pointers to the
1091 updated declaration.
1093 If there was a definition for the template, but
1094 not for the specialization, we want this to
1095 look as if there were no definition, and vice
1097 DECL_INITIAL (fn) = NULL_TREE;
1098 duplicate_decls (spec, fn);
1103 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1105 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
1106 /* Dup decl failed, but this is a new
1107 definition. Set the line number so any errors
1108 match this new definition. */
1109 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1117 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1118 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1123 /* Unregister the specialization SPEC as a specialization of TMPL.
1124 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1125 if the SPEC was listed as a specialization of TMPL. */
1128 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1132 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1134 s = &TREE_CHAIN (*s))
1135 if (TREE_VALUE (*s) == spec)
1138 *s = TREE_CHAIN (*s);
1140 TREE_VALUE (*s) = new_spec;
1147 /* Compare an entry in the local specializations hash table P1 (which
1148 is really a pointer to a TREE_LIST) with P2 (which is really a
1152 eq_local_specializations (const void *p1, const void *p2)
1154 return TREE_VALUE ((tree) p1) == (tree) p2;
1157 /* Hash P1, an entry in the local specializations table. */
1160 hash_local_specialization (const void* p1)
1162 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1165 /* Like register_specialization, but for local declarations. We are
1166 registering SPEC, an instantiation of TMPL. */
1169 register_local_specialization (tree spec, tree tmpl)
1173 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1174 htab_hash_pointer (tmpl), INSERT);
1175 *slot = build_tree_list (spec, tmpl);
1178 /* Print the list of candidate FNS in an error message. */
1181 print_candidates (tree fns)
1185 const char *str = "candidates are:";
1187 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1191 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1192 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
1197 /* Returns the template (one of the functions given by TEMPLATE_ID)
1198 which can be specialized to match the indicated DECL with the
1199 explicit template args given in TEMPLATE_ID. The DECL may be
1200 NULL_TREE if none is available. In that case, the functions in
1201 TEMPLATE_ID are non-members.
1203 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1204 specialization of a member template.
1206 The template args (those explicitly specified and those deduced)
1207 are output in a newly created vector *TARGS_OUT.
1209 If it is impossible to determine the result, an error message is
1210 issued. The error_mark_node is returned to indicate failure. */
1213 determine_specialization (tree template_id,
1216 int need_member_template)
1220 tree explicit_targs;
1221 tree candidates = NULL_TREE;
1222 tree templates = NULL_TREE;
1224 *targs_out = NULL_TREE;
1226 if (template_id == error_mark_node)
1227 return error_mark_node;
1229 fns = TREE_OPERAND (template_id, 0);
1230 explicit_targs = TREE_OPERAND (template_id, 1);
1232 if (fns == error_mark_node)
1233 return error_mark_node;
1235 /* Check for baselinks. */
1236 if (BASELINK_P (fns))
1237 fns = BASELINK_FUNCTIONS (fns);
1239 if (!is_overloaded_fn (fns))
1241 error ("`%D' is not a function template", fns);
1242 return error_mark_node;
1245 for (; fns; fns = OVL_NEXT (fns))
1247 tree fn = OVL_CURRENT (fns);
1249 if (TREE_CODE (fn) == TEMPLATE_DECL)
1251 tree decl_arg_types;
1253 /* DECL might be a specialization of FN. */
1255 /* Adjust the type of DECL in case FN is a static member. */
1256 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1257 if (DECL_STATIC_FUNCTION_P (fn)
1258 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1259 decl_arg_types = TREE_CHAIN (decl_arg_types);
1261 /* Check that the number of function parameters matches.
1263 template <class T> void f(int i = 0);
1264 template <> void f<int>();
1265 The specialization f<int> is invalid but is not caught
1266 by get_bindings below. */
1268 if (list_length (TYPE_ARG_TYPES (TREE_TYPE (fn)))
1269 != list_length (decl_arg_types))
1272 /* See whether this function might be a specialization of this
1274 targs = get_bindings (fn, decl, explicit_targs);
1277 /* We cannot deduce template arguments that when used to
1278 specialize TMPL will produce DECL. */
1281 /* Save this template, and the arguments deduced. */
1282 templates = tree_cons (targs, fn, templates);
1284 else if (need_member_template)
1285 /* FN is an ordinary member function, and we need a
1286 specialization of a member template. */
1288 else if (TREE_CODE (fn) != FUNCTION_DECL)
1289 /* We can get IDENTIFIER_NODEs here in certain erroneous
1292 else if (!DECL_FUNCTION_MEMBER_P (fn))
1293 /* This is just an ordinary non-member function. Nothing can
1294 be a specialization of that. */
1296 else if (DECL_ARTIFICIAL (fn))
1297 /* Cannot specialize functions that are created implicitly. */
1301 tree decl_arg_types;
1303 /* This is an ordinary member function. However, since
1304 we're here, we can assume it's enclosing class is a
1305 template class. For example,
1307 template <typename T> struct S { void f(); };
1308 template <> void S<int>::f() {}
1310 Here, S<int>::f is a non-template, but S<int> is a
1311 template class. If FN has the same type as DECL, we
1312 might be in business. */
1314 if (!DECL_TEMPLATE_INFO (fn))
1315 /* Its enclosing class is an explicit specialization
1316 of a template class. This is not a candidate. */
1319 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1320 TREE_TYPE (TREE_TYPE (fn))))
1321 /* The return types differ. */
1324 /* Adjust the type of DECL in case FN is a static member. */
1325 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1326 if (DECL_STATIC_FUNCTION_P (fn)
1327 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1328 decl_arg_types = TREE_CHAIN (decl_arg_types);
1330 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1333 candidates = tree_cons (NULL_TREE, fn, candidates);
1337 if (templates && TREE_CHAIN (templates))
1343 It is possible for a specialization with a given function
1344 signature to be instantiated from more than one function
1345 template. In such cases, explicit specification of the
1346 template arguments must be used to uniquely identify the
1347 function template specialization being specialized.
1349 Note that here, there's no suggestion that we're supposed to
1350 determine which of the candidate templates is most
1351 specialized. However, we, also have:
1355 Partial ordering of overloaded function template
1356 declarations is used in the following contexts to select
1357 the function template to which a function template
1358 specialization refers:
1360 -- when an explicit specialization refers to a function
1363 So, we do use the partial ordering rules, at least for now.
1364 This extension can only serve to make invalid programs valid,
1365 so it's safe. And, there is strong anecdotal evidence that
1366 the committee intended the partial ordering rules to apply;
1367 the EDG front-end has that behavior, and John Spicer claims
1368 that the committee simply forgot to delete the wording in
1369 [temp.expl.spec]. */
1370 tree tmpl = most_specialized (templates, decl, explicit_targs);
1371 if (tmpl && tmpl != error_mark_node)
1373 targs = get_bindings (tmpl, decl, explicit_targs);
1374 templates = tree_cons (targs, tmpl, NULL_TREE);
1378 if (templates == NULL_TREE && candidates == NULL_TREE)
1380 cp_error_at ("template-id `%D' for `%+D' does not match any template declaration",
1382 return error_mark_node;
1384 else if ((templates && TREE_CHAIN (templates))
1385 || (candidates && TREE_CHAIN (candidates))
1386 || (templates && candidates))
1388 cp_error_at ("ambiguous template specialization `%D' for `%+D'",
1390 chainon (candidates, templates);
1391 print_candidates (candidates);
1392 return error_mark_node;
1395 /* We have one, and exactly one, match. */
1398 /* It was a specialization of an ordinary member function in a
1400 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1401 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1404 /* It was a specialization of a template. */
1405 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1406 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1408 *targs_out = copy_node (targs);
1409 SET_TMPL_ARGS_LEVEL (*targs_out,
1410 TMPL_ARGS_DEPTH (*targs_out),
1411 TREE_PURPOSE (templates));
1414 *targs_out = TREE_PURPOSE (templates);
1415 return TREE_VALUE (templates);
1418 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1419 but with the default argument values filled in from those in the
1423 copy_default_args_to_explicit_spec_1 (tree spec_types,
1426 tree new_spec_types;
1431 if (spec_types == void_list_node)
1432 return void_list_node;
1434 /* Substitute into the rest of the list. */
1436 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1437 TREE_CHAIN (tmpl_types));
1439 /* Add the default argument for this parameter. */
1440 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1441 TREE_VALUE (spec_types),
1445 /* DECL is an explicit specialization. Replicate default arguments
1446 from the template it specializes. (That way, code like:
1448 template <class T> void f(T = 3);
1449 template <> void f(double);
1452 works, as required.) An alternative approach would be to look up
1453 the correct default arguments at the call-site, but this approach
1454 is consistent with how implicit instantiations are handled. */
1457 copy_default_args_to_explicit_spec (tree decl)
1462 tree new_spec_types;
1466 tree object_type = NULL_TREE;
1467 tree in_charge = NULL_TREE;
1468 tree vtt = NULL_TREE;
1470 /* See if there's anything we need to do. */
1471 tmpl = DECL_TI_TEMPLATE (decl);
1472 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1473 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1474 if (TREE_PURPOSE (t))
1479 old_type = TREE_TYPE (decl);
1480 spec_types = TYPE_ARG_TYPES (old_type);
1482 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1484 /* Remove the this pointer, but remember the object's type for
1486 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1487 spec_types = TREE_CHAIN (spec_types);
1488 tmpl_types = TREE_CHAIN (tmpl_types);
1490 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1492 /* DECL may contain more parameters than TMPL due to the extra
1493 in-charge parameter in constructors and destructors. */
1494 in_charge = spec_types;
1495 spec_types = TREE_CHAIN (spec_types);
1497 if (DECL_HAS_VTT_PARM_P (decl))
1500 spec_types = TREE_CHAIN (spec_types);
1504 /* Compute the merged default arguments. */
1506 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1508 /* Compute the new FUNCTION_TYPE. */
1512 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1517 /* Put the in-charge parameter back. */
1518 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1519 TREE_VALUE (in_charge),
1522 new_type = build_method_type_directly (object_type,
1523 TREE_TYPE (old_type),
1527 new_type = build_function_type (TREE_TYPE (old_type),
1529 new_type = cp_build_type_attribute_variant (new_type,
1530 TYPE_ATTRIBUTES (old_type));
1531 new_type = build_exception_variant (new_type,
1532 TYPE_RAISES_EXCEPTIONS (old_type));
1533 TREE_TYPE (decl) = new_type;
1536 /* Check to see if the function just declared, as indicated in
1537 DECLARATOR, and in DECL, is a specialization of a function
1538 template. We may also discover that the declaration is an explicit
1539 instantiation at this point.
1541 Returns DECL, or an equivalent declaration that should be used
1542 instead if all goes well. Issues an error message if something is
1543 amiss. Returns error_mark_node if the error is not easily
1546 FLAGS is a bitmask consisting of the following flags:
1548 2: The function has a definition.
1549 4: The function is a friend.
1551 The TEMPLATE_COUNT is the number of references to qualifying
1552 template classes that appeared in the name of the function. For
1555 template <class T> struct S { void f(); };
1558 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1559 classes are not counted in the TEMPLATE_COUNT, so that in
1561 template <class T> struct S {};
1562 template <> struct S<int> { void f(); }
1563 template <> void S<int>::f();
1565 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1566 invalid; there should be no template <>.)
1568 If the function is a specialization, it is marked as such via
1569 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1570 is set up correctly, and it is added to the list of specializations
1571 for that template. */
1574 check_explicit_specialization (tree declarator,
1579 int have_def = flags & 2;
1580 int is_friend = flags & 4;
1581 int specialization = 0;
1582 int explicit_instantiation = 0;
1583 int member_specialization = 0;
1584 tree ctype = DECL_CLASS_CONTEXT (decl);
1585 tree dname = DECL_NAME (decl);
1588 tsk = current_tmpl_spec_kind (template_count);
1593 if (processing_specialization)
1596 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1598 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1601 /* This could be something like:
1603 template <class T> void f(T);
1604 class S { friend void f<>(int); } */
1608 /* This case handles bogus declarations like template <>
1609 template <class T> void f<int>(); */
1611 error ("template-id `%D' in declaration of primary template",
1618 case tsk_invalid_member_spec:
1619 /* The error has already been reported in
1620 check_specialization_scope. */
1621 return error_mark_node;
1623 case tsk_invalid_expl_inst:
1624 error ("template parameter list used in explicit instantiation");
1630 error ("definition provided for explicit instantiation");
1632 explicit_instantiation = 1;
1635 case tsk_excessive_parms:
1636 error ("too many template parameter lists in declaration of `%D'",
1638 return error_mark_node;
1642 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1644 member_specialization = 1;
1649 case tsk_insufficient_parms:
1650 if (template_header_count)
1652 error("too few template parameter lists in declaration of `%D'",
1656 else if (ctype != NULL_TREE
1657 && !TYPE_BEING_DEFINED (ctype)
1658 && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype)
1661 /* For backwards compatibility, we accept:
1663 template <class T> struct S { void f(); };
1664 void S<int>::f() {} // Missing template <>
1666 That used to be valid C++. */
1669 ("explicit specialization not preceded by `template <>'");
1671 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1676 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1678 /* This case handles bogus declarations like template <>
1679 template <class T> void f<int>(); */
1681 if (uses_template_parms (declarator))
1682 error ("partial specialization `%D' of function template",
1685 error ("template-id `%D' in declaration of primary template",
1690 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1691 /* This is a specialization of a member template, without
1692 specialization the containing class. Something like:
1694 template <class T> struct S {
1695 template <class U> void f (U);
1697 template <> template <class U> void S<int>::f(U) {}
1699 That's a specialization -- but of the entire template. */
1707 if (specialization || member_specialization)
1709 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1710 for (; t; t = TREE_CHAIN (t))
1711 if (TREE_PURPOSE (t))
1714 ("default argument specified in explicit specialization");
1717 if (current_lang_name == lang_name_c)
1718 error ("template specialization with C linkage");
1721 if (specialization || member_specialization || explicit_instantiation)
1723 tree tmpl = NULL_TREE;
1724 tree targs = NULL_TREE;
1726 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1727 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1731 my_friendly_assert (TREE_CODE (declarator) == IDENTIFIER_NODE, 0);
1736 /* If there is no class context, the explicit instantiation
1737 must be at namespace scope. */
1738 my_friendly_assert (DECL_NAMESPACE_SCOPE_P (decl), 20030625);
1740 /* Find the namespace binding, using the declaration
1742 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1745 declarator = lookup_template_function (fns, NULL_TREE);
1748 if (declarator == error_mark_node)
1749 return error_mark_node;
1751 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1753 if (!explicit_instantiation)
1754 /* A specialization in class scope. This is invalid,
1755 but the error will already have been flagged by
1756 check_specialization_scope. */
1757 return error_mark_node;
1760 /* It's not valid to write an explicit instantiation in
1763 class C { template void f(); }
1765 This case is caught by the parser. However, on
1768 template class C { void f(); };
1770 (which is invalid) we can get here. The error will be
1777 else if (ctype != NULL_TREE
1778 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1781 /* Find the list of functions in ctype that have the same
1782 name as the declared function. */
1783 tree name = TREE_OPERAND (declarator, 0);
1784 tree fns = NULL_TREE;
1787 if (constructor_name_p (name, ctype))
1789 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1791 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1792 : !TYPE_HAS_DESTRUCTOR (ctype))
1794 /* From [temp.expl.spec]:
1796 If such an explicit specialization for the member
1797 of a class template names an implicitly-declared
1798 special member function (clause _special_), the
1799 program is ill-formed.
1801 Similar language is found in [temp.explicit]. */
1802 error ("specialization of implicitly-declared special member function");
1803 return error_mark_node;
1806 name = is_constructor ? ctor_identifier : dtor_identifier;
1809 if (!DECL_CONV_FN_P (decl))
1811 idx = lookup_fnfields_1 (ctype, name);
1813 fns = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (ctype), idx);
1819 /* For a type-conversion operator, we cannot do a
1820 name-based lookup. We might be looking for `operator
1821 int' which will be a specialization of `operator T'.
1822 So, we find *all* the conversion operators, and then
1823 select from them. */
1826 methods = CLASSTYPE_METHOD_VEC (ctype);
1828 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1829 idx < TREE_VEC_LENGTH (methods); ++idx)
1831 tree ovl = TREE_VEC_ELT (methods, idx);
1833 if (!ovl || !DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1834 /* There are no more conversion functions. */
1837 /* Glue all these conversion functions together
1838 with those we already have. */
1839 for (; ovl; ovl = OVL_NEXT (ovl))
1840 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1844 if (fns == NULL_TREE)
1846 error ("no member function `%D' declared in `%T'",
1848 return error_mark_node;
1851 TREE_OPERAND (declarator, 0) = fns;
1854 /* Figure out what exactly is being specialized at this point.
1855 Note that for an explicit instantiation, even one for a
1856 member function, we cannot tell apriori whether the
1857 instantiation is for a member template, or just a member
1858 function of a template class. Even if a member template is
1859 being instantiated, the member template arguments may be
1860 elided if they can be deduced from the rest of the
1862 tmpl = determine_specialization (declarator, decl,
1864 member_specialization);
1866 if (!tmpl || tmpl == error_mark_node)
1867 /* We couldn't figure out what this declaration was
1869 return error_mark_node;
1872 tree gen_tmpl = most_general_template (tmpl);
1874 if (explicit_instantiation)
1876 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
1877 is done by do_decl_instantiation later. */
1879 int arg_depth = TMPL_ARGS_DEPTH (targs);
1880 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
1882 if (arg_depth > parm_depth)
1884 /* If TMPL is not the most general template (for
1885 example, if TMPL is a friend template that is
1886 injected into namespace scope), then there will
1887 be too many levels of TARGS. Remove some of them
1892 new_targs = make_tree_vec (parm_depth);
1893 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
1894 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
1895 = TREE_VEC_ELT (targs, i);
1899 return instantiate_template (tmpl, targs, tf_error);
1902 /* If we thought that the DECL was a member function, but it
1903 turns out to be specializing a static member function,
1904 make DECL a static member function as well. We also have
1905 to adjust last_function_parms to avoid confusing
1906 start_function later. */
1907 if (DECL_STATIC_FUNCTION_P (tmpl)
1908 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1910 revert_static_member_fn (decl);
1911 last_function_parms = TREE_CHAIN (last_function_parms);
1914 /* If this is a specialization of a member template of a
1915 template class. In we want to return the TEMPLATE_DECL,
1916 not the specialization of it. */
1917 if (tsk == tsk_template)
1919 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
1920 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
1923 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
1924 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
1925 = DECL_SOURCE_LOCATION (decl);
1930 /* Set up the DECL_TEMPLATE_INFO for DECL. */
1931 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
1933 /* Inherit default function arguments from the template
1934 DECL is specializing. */
1935 copy_default_args_to_explicit_spec (decl);
1937 /* This specialization has the same protection as the
1938 template it specializes. */
1939 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
1940 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
1942 if (is_friend && !have_def)
1943 /* This is not really a declaration of a specialization.
1944 It's just the name of an instantiation. But, it's not
1945 a request for an instantiation, either. */
1946 SET_DECL_IMPLICIT_INSTANTIATION (decl);
1947 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
1948 /* This is indeed a specialization. In case of constructors
1949 and destructors, we need in-charge and not-in-charge
1950 versions in V3 ABI. */
1951 clone_function_decl (decl, /*update_method_vec_p=*/0);
1953 /* Register this specialization so that we can find it
1955 decl = register_specialization (decl, gen_tmpl, targs);
1962 /* TYPE is being declared. Verify that the use of template headers
1963 and such is reasonable. Issue error messages if not. */
1966 maybe_check_template_type (tree type)
1968 if (template_header_count)
1970 /* We are in the scope of some `template <...>' header. */
1973 = template_class_depth_real (TYPE_CONTEXT (type),
1974 /*count_specializations=*/1);
1976 if (template_header_count <= context_depth)
1977 /* This is OK; the template headers are for the context. We
1978 are actually too lenient here; like
1979 check_explicit_specialization we should consider the number
1980 of template types included in the actual declaration. For
1983 template <class T> struct S {
1984 template <class U> template <class V>
1990 template <class T> struct S {
1991 template <class U> struct I;
1994 template <class T> template <class U.
1999 else if (template_header_count > context_depth + 1)
2000 /* There are two many template parameter lists. */
2001 error ("too many template parameter lists in declaration of `%T'", type);
2005 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2006 parameters. These are represented in the same format used for
2007 DECL_TEMPLATE_PARMS. */
2009 int comp_template_parms (tree parms1, tree parms2)
2014 if (parms1 == parms2)
2017 for (p1 = parms1, p2 = parms2;
2018 p1 != NULL_TREE && p2 != NULL_TREE;
2019 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2021 tree t1 = TREE_VALUE (p1);
2022 tree t2 = TREE_VALUE (p2);
2025 my_friendly_assert (TREE_CODE (t1) == TREE_VEC, 0);
2026 my_friendly_assert (TREE_CODE (t2) == TREE_VEC, 0);
2028 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2031 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2033 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2034 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2036 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2039 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2041 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2046 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2047 /* One set of parameters has more parameters lists than the
2054 /* Complain if DECL shadows a template parameter.
2056 [temp.local]: A template-parameter shall not be redeclared within its
2057 scope (including nested scopes). */
2060 check_template_shadow (tree decl)
2064 /* If we're not in a template, we can't possibly shadow a template
2066 if (!current_template_parms)
2069 /* Figure out what we're shadowing. */
2070 if (TREE_CODE (decl) == OVERLOAD)
2071 decl = OVL_CURRENT (decl);
2072 olddecl = IDENTIFIER_VALUE (DECL_NAME (decl));
2074 /* If there's no previous binding for this name, we're not shadowing
2075 anything, let alone a template parameter. */
2079 /* If we're not shadowing a template parameter, we're done. Note
2080 that OLDDECL might be an OVERLOAD (or perhaps even an
2081 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2083 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2086 /* We check for decl != olddecl to avoid bogus errors for using a
2087 name inside a class. We check TPFI to avoid duplicate errors for
2088 inline member templates. */
2090 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2093 cp_error_at ("declaration of `%#D'", decl);
2094 cp_error_at (" shadows template parm `%#D'", olddecl);
2097 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2098 ORIG_LEVEL, DECL, and TYPE. */
2101 build_template_parm_index (int index,
2107 tree t = make_node (TEMPLATE_PARM_INDEX);
2108 TEMPLATE_PARM_IDX (t) = index;
2109 TEMPLATE_PARM_LEVEL (t) = level;
2110 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2111 TEMPLATE_PARM_DECL (t) = decl;
2112 TREE_TYPE (t) = type;
2113 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2114 TREE_READONLY (t) = TREE_READONLY (decl);
2119 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2120 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2121 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2122 new one is created. */
2125 reduce_template_parm_level (tree index, tree type, int levels)
2127 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2128 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2129 != TEMPLATE_PARM_LEVEL (index) - levels))
2131 tree orig_decl = TEMPLATE_PARM_DECL (index);
2134 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2135 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2136 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2137 DECL_ARTIFICIAL (decl) = 1;
2138 SET_DECL_TEMPLATE_PARM_P (decl);
2140 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2141 TEMPLATE_PARM_LEVEL (index) - levels,
2142 TEMPLATE_PARM_ORIG_LEVEL (index),
2144 TEMPLATE_PARM_DESCENDANTS (index) = t;
2146 /* Template template parameters need this. */
2147 DECL_TEMPLATE_PARMS (decl)
2148 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2151 return TEMPLATE_PARM_DESCENDANTS (index);
2154 /* Process information from new template parameter NEXT and append it to the
2155 LIST being built. */
2158 process_template_parm (tree list, tree next)
2166 my_friendly_assert (TREE_CODE (parm) == TREE_LIST, 259);
2167 defval = TREE_PURPOSE (parm);
2168 parm = TREE_VALUE (parm);
2169 is_type = TREE_PURPOSE (parm) == class_type_node;
2173 tree p = TREE_VALUE (tree_last (list));
2175 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2176 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2178 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2186 my_friendly_assert (TREE_CODE (TREE_PURPOSE (parm)) == TREE_LIST, 260);
2187 /* is a const-param */
2188 parm = grokdeclarator (TREE_VALUE (parm), TREE_PURPOSE (parm),
2190 SET_DECL_TEMPLATE_PARM_P (parm);
2194 The top-level cv-qualifiers on the template-parameter are
2195 ignored when determining its type. */
2196 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2198 /* A template parameter is not modifiable. */
2199 TREE_READONLY (parm) = TREE_CONSTANT (parm) = 1;
2200 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2201 TREE_TYPE (parm) = void_type_node;
2202 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2203 TREE_CONSTANT (decl) = TREE_READONLY (decl) = 1;
2204 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2205 = build_template_parm_index (idx, processing_template_decl,
2206 processing_template_decl,
2207 decl, TREE_TYPE (parm));
2212 parm = TREE_VALUE (parm);
2214 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2216 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2217 /* This is for distinguishing between real templates and template
2218 template parameters */
2219 TREE_TYPE (parm) = t;
2220 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2225 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2226 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2227 decl = build_decl (TYPE_DECL, parm, t);
2230 TYPE_NAME (t) = decl;
2231 TYPE_STUB_DECL (t) = decl;
2233 TEMPLATE_TYPE_PARM_INDEX (t)
2234 = build_template_parm_index (idx, processing_template_decl,
2235 processing_template_decl,
2236 decl, TREE_TYPE (parm));
2238 DECL_ARTIFICIAL (decl) = 1;
2239 SET_DECL_TEMPLATE_PARM_P (decl);
2241 parm = build_tree_list (defval, parm);
2242 return chainon (list, parm);
2245 /* The end of a template parameter list has been reached. Process the
2246 tree list into a parameter vector, converting each parameter into a more
2247 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2251 end_template_parm_list (tree parms)
2255 tree saved_parmlist = make_tree_vec (list_length (parms));
2257 current_template_parms
2258 = tree_cons (size_int (processing_template_decl),
2259 saved_parmlist, current_template_parms);
2261 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2263 next = TREE_CHAIN (parm);
2264 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2265 TREE_CHAIN (parm) = NULL_TREE;
2268 --processing_template_parmlist;
2270 return saved_parmlist;
2273 /* end_template_decl is called after a template declaration is seen. */
2276 end_template_decl (void)
2278 reset_specialization ();
2280 if (! processing_template_decl)
2283 /* This matches the pushlevel in begin_template_parm_list. */
2286 --processing_template_decl;
2287 current_template_parms = TREE_CHAIN (current_template_parms);
2290 /* Given a template argument vector containing the template PARMS.
2291 The innermost PARMS are given first. */
2294 current_template_args (void)
2297 tree args = NULL_TREE;
2298 int length = TMPL_PARMS_DEPTH (current_template_parms);
2301 /* If there is only one level of template parameters, we do not
2302 create a TREE_VEC of TREE_VECs. Instead, we return a single
2303 TREE_VEC containing the arguments. */
2305 args = make_tree_vec (length);
2307 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2309 tree a = copy_node (TREE_VALUE (header));
2312 TREE_TYPE (a) = NULL_TREE;
2313 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2315 tree t = TREE_VEC_ELT (a, i);
2317 /* T will be a list if we are called from within a
2318 begin/end_template_parm_list pair, but a vector directly
2319 if within a begin/end_member_template_processing pair. */
2320 if (TREE_CODE (t) == TREE_LIST)
2324 if (TREE_CODE (t) == TYPE_DECL
2325 || TREE_CODE (t) == TEMPLATE_DECL)
2328 t = DECL_INITIAL (t);
2329 TREE_VEC_ELT (a, i) = t;
2334 TREE_VEC_ELT (args, --l) = a;
2342 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2343 template PARMS. Used by push_template_decl below. */
2346 build_template_decl (tree decl, tree parms)
2348 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2349 DECL_TEMPLATE_PARMS (tmpl) = parms;
2350 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2351 if (DECL_LANG_SPECIFIC (decl))
2353 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2354 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2355 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2356 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2357 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2358 if (DECL_OVERLOADED_OPERATOR_P (decl))
2359 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2360 DECL_OVERLOADED_OPERATOR_P (decl));
2366 struct template_parm_data
2368 /* The level of the template parameters we are currently
2372 /* The index of the specialization argument we are currently
2376 /* An array whose size is the number of template parameters. The
2377 elements are nonzero if the parameter has been used in any one
2378 of the arguments processed so far. */
2381 /* An array whose size is the number of template arguments. The
2382 elements are nonzero if the argument makes use of template
2383 parameters of this level. */
2384 int* arg_uses_template_parms;
2387 /* Subroutine of push_template_decl used to see if each template
2388 parameter in a partial specialization is used in the explicit
2389 argument list. If T is of the LEVEL given in DATA (which is
2390 treated as a template_parm_data*), then DATA->PARMS is marked
2394 mark_template_parm (tree t, void* data)
2398 struct template_parm_data* tpd = (struct template_parm_data*) data;
2400 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2402 level = TEMPLATE_PARM_LEVEL (t);
2403 idx = TEMPLATE_PARM_IDX (t);
2407 level = TEMPLATE_TYPE_LEVEL (t);
2408 idx = TEMPLATE_TYPE_IDX (t);
2411 if (level == tpd->level)
2413 tpd->parms[idx] = 1;
2414 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2417 /* Return zero so that for_each_template_parm will continue the
2418 traversal of the tree; we want to mark *every* template parm. */
2422 /* Process the partial specialization DECL. */
2425 process_partial_specialization (tree decl)
2427 tree type = TREE_TYPE (decl);
2428 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2429 tree specargs = CLASSTYPE_TI_ARGS (type);
2430 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2431 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2432 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2433 int nargs = TREE_VEC_LENGTH (inner_args);
2434 int ntparms = TREE_VEC_LENGTH (inner_parms);
2436 int did_error_intro = 0;
2437 struct template_parm_data tpd;
2438 struct template_parm_data tpd2;
2440 /* We check that each of the template parameters given in the
2441 partial specialization is used in the argument list to the
2442 specialization. For example:
2444 template <class T> struct S;
2445 template <class T> struct S<T*>;
2447 The second declaration is OK because `T*' uses the template
2448 parameter T, whereas
2450 template <class T> struct S<int>;
2452 is no good. Even trickier is:
2463 The S2<T> declaration is actually invalid; it is a
2464 full-specialization. Of course,
2467 struct S2<T (*)(U)>;
2469 or some such would have been OK. */
2470 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2471 tpd.parms = alloca (sizeof (int) * ntparms);
2472 memset (tpd.parms, 0, sizeof (int) * ntparms);
2474 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2475 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2476 for (i = 0; i < nargs; ++i)
2478 tpd.current_arg = i;
2479 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2480 &mark_template_parm,
2484 for (i = 0; i < ntparms; ++i)
2485 if (tpd.parms[i] == 0)
2487 /* One of the template parms was not used in the
2489 if (!did_error_intro)
2491 error ("template parameters not used in partial specialization:");
2492 did_error_intro = 1;
2496 TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2499 /* [temp.class.spec]
2501 The argument list of the specialization shall not be identical to
2502 the implicit argument list of the primary template. */
2503 if (comp_template_args
2505 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2507 error ("partial specialization `%T' does not specialize any template arguments", type);
2509 /* [temp.class.spec]
2511 A partially specialized non-type argument expression shall not
2512 involve template parameters of the partial specialization except
2513 when the argument expression is a simple identifier.
2515 The type of a template parameter corresponding to a specialized
2516 non-type argument shall not be dependent on a parameter of the
2518 my_friendly_assert (nargs == DECL_NTPARMS (maintmpl), 0);
2520 for (i = 0; i < nargs; ++i)
2522 tree arg = TREE_VEC_ELT (inner_args, i);
2523 if (/* These first two lines are the `non-type' bit. */
2525 && TREE_CODE (arg) != TEMPLATE_DECL
2526 /* This next line is the `argument expression is not just a
2527 simple identifier' condition and also the `specialized
2528 non-type argument' bit. */
2529 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2531 if (tpd.arg_uses_template_parms[i])
2532 error ("template argument `%E' involves template parameter(s)", arg);
2535 /* Look at the corresponding template parameter,
2536 marking which template parameters its type depends
2539 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2544 /* We haven't yet initialized TPD2. Do so now. */
2545 tpd2.arg_uses_template_parms
2546 = alloca (sizeof (int) * nargs);
2547 /* The number of parameters here is the number in the
2548 main template, which, as checked in the assertion
2550 tpd2.parms = alloca (sizeof (int) * nargs);
2552 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2555 /* Mark the template parameters. But this time, we're
2556 looking for the template parameters of the main
2557 template, not in the specialization. */
2558 tpd2.current_arg = i;
2559 tpd2.arg_uses_template_parms[i] = 0;
2560 memset (tpd2.parms, 0, sizeof (int) * nargs);
2561 for_each_template_parm (type,
2562 &mark_template_parm,
2566 if (tpd2.arg_uses_template_parms [i])
2568 /* The type depended on some template parameters.
2569 If they are fully specialized in the
2570 specialization, that's OK. */
2572 for (j = 0; j < nargs; ++j)
2573 if (tpd2.parms[j] != 0
2574 && tpd.arg_uses_template_parms [j])
2576 error ("type `%T' of template argument `%E' depends on template parameter(s)",
2586 if (retrieve_specialization (maintmpl, specargs))
2587 /* We've already got this specialization. */
2590 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2591 = tree_cons (inner_args, inner_parms,
2592 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2593 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2597 /* Check that a template declaration's use of default arguments is not
2598 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2599 nonzero if DECL is the thing declared by a primary template.
2600 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2603 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2606 int last_level_to_check;
2611 A default template-argument shall not be specified in a
2612 function template declaration or a function template definition, nor
2613 in the template-parameter-list of the definition of a member of a
2616 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2617 /* You can't have a function template declaration in a local
2618 scope, nor you can you define a member of a class template in a
2622 if (current_class_type
2623 && !TYPE_BEING_DEFINED (current_class_type)
2624 && DECL_LANG_SPECIFIC (decl)
2625 /* If this is either a friend defined in the scope of the class
2626 or a member function. */
2627 && (DECL_FUNCTION_MEMBER_P (decl)
2628 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2629 : DECL_FRIEND_CONTEXT (decl)
2630 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2632 /* And, if it was a member function, it really was defined in
2633 the scope of the class. */
2634 && (!DECL_FUNCTION_MEMBER_P (decl)
2635 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2636 /* We already checked these parameters when the template was
2637 declared, so there's no need to do it again now. This function
2638 was defined in class scope, but we're processing it's body now
2639 that the class is complete. */
2644 If a template-parameter has a default template-argument, all
2645 subsequent template-parameters shall have a default
2646 template-argument supplied. */
2647 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2649 tree inner_parms = TREE_VALUE (parm_level);
2650 int ntparms = TREE_VEC_LENGTH (inner_parms);
2651 int seen_def_arg_p = 0;
2654 for (i = 0; i < ntparms; ++i)
2656 tree parm = TREE_VEC_ELT (inner_parms, i);
2657 if (TREE_PURPOSE (parm))
2659 else if (seen_def_arg_p)
2661 error ("no default argument for `%D'", TREE_VALUE (parm));
2662 /* For better subsequent error-recovery, we indicate that
2663 there should have been a default argument. */
2664 TREE_PURPOSE (parm) = error_mark_node;
2669 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2670 /* For an ordinary class template, default template arguments are
2671 allowed at the innermost level, e.g.:
2672 template <class T = int>
2674 but, in a partial specialization, they're not allowed even
2675 there, as we have in [temp.class.spec]:
2677 The template parameter list of a specialization shall not
2678 contain default template argument values.
2680 So, for a partial specialization, or for a function template,
2681 we look at all of them. */
2684 /* But, for a primary class template that is not a partial
2685 specialization we look at all template parameters except the
2687 parms = TREE_CHAIN (parms);
2689 /* Figure out what error message to issue. */
2690 if (TREE_CODE (decl) == FUNCTION_DECL)
2691 msg = "default template arguments may not be used in function templates";
2692 else if (is_partial)
2693 msg = "default template arguments may not be used in partial specializations";
2695 msg = "default argument for template parameter for class enclosing `%D'";
2697 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2698 /* If we're inside a class definition, there's no need to
2699 examine the parameters to the class itself. On the one
2700 hand, they will be checked when the class is defined, and,
2701 on the other, default arguments are valid in things like:
2702 template <class T = double>
2703 struct S { template <class U> void f(U); };
2704 Here the default argument for `S' has no bearing on the
2705 declaration of `f'. */
2706 last_level_to_check = template_class_depth (current_class_type) + 1;
2708 /* Check everything. */
2709 last_level_to_check = 0;
2711 for (parm_level = parms;
2712 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2713 parm_level = TREE_CHAIN (parm_level))
2715 tree inner_parms = TREE_VALUE (parm_level);
2719 ntparms = TREE_VEC_LENGTH (inner_parms);
2720 for (i = 0; i < ntparms; ++i)
2721 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2729 /* Clear out the default argument so that we are not
2731 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2734 /* At this point, if we're still interested in issuing messages,
2735 they must apply to classes surrounding the object declared. */
2737 msg = "default argument for template parameter for class enclosing `%D'";
2741 /* Worker for push_template_decl_real, called via
2742 for_each_template_parm. DATA is really an int, indicating the
2743 level of the parameters we are interested in. If T is a template
2744 parameter of that level, return nonzero. */
2747 template_parm_this_level_p (tree t, void* data)
2749 int this_level = *(int *)data;
2752 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2753 level = TEMPLATE_PARM_LEVEL (t);
2755 level = TEMPLATE_TYPE_LEVEL (t);
2756 return level == this_level;
2759 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2760 parameters given by current_template_args, or reuses a
2761 previously existing one, if appropriate. Returns the DECL, or an
2762 equivalent one, if it is replaced via a call to duplicate_decls.
2764 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2767 push_template_decl_real (tree decl, int is_friend)
2775 int new_template_p = 0;
2777 if (decl == error_mark_node)
2780 /* See if this is a partial specialization. */
2781 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2782 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2783 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2785 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2788 /* For a friend, we want the context of the friend function, not
2789 the type of which it is a friend. */
2790 ctx = DECL_CONTEXT (decl);
2791 else if (CP_DECL_CONTEXT (decl)
2792 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2793 /* In the case of a virtual function, we want the class in which
2795 ctx = CP_DECL_CONTEXT (decl);
2797 /* Otherwise, if we're currently defining some class, the DECL
2798 is assumed to be a member of the class. */
2799 ctx = current_scope ();
2801 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2804 if (!DECL_CONTEXT (decl))
2805 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2807 /* See if this is a primary template. */
2808 primary = template_parm_scope_p ();
2812 if (current_lang_name == lang_name_c)
2813 error ("template with C linkage");
2814 else if (TREE_CODE (decl) == TYPE_DECL
2815 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2816 error ("template class without a name");
2817 else if (TREE_CODE (decl) == FUNCTION_DECL
2818 && DECL_DESTRUCTOR_P (decl))
2822 A destructor shall not be a member template. */
2823 error ("destructor `%D' declared as member template", decl);
2824 return error_mark_node;
2826 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2827 && CLASS_TYPE_P (TREE_TYPE (decl)))
2828 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx))
2829 || TREE_CODE (decl) == FUNCTION_DECL)
2833 error ("template declaration of `%#D'", decl);
2834 return error_mark_node;
2838 /* Check to see that the rules regarding the use of default
2839 arguments are not being violated. */
2840 check_default_tmpl_args (decl, current_template_parms,
2841 primary, is_partial);
2844 return process_partial_specialization (decl);
2846 args = current_template_args ();
2849 || TREE_CODE (ctx) == FUNCTION_DECL
2850 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
2851 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
2853 if (DECL_LANG_SPECIFIC (decl)
2854 && DECL_TEMPLATE_INFO (decl)
2855 && DECL_TI_TEMPLATE (decl))
2856 tmpl = DECL_TI_TEMPLATE (decl);
2857 /* If DECL is a TYPE_DECL for a class-template, then there won't
2858 be DECL_LANG_SPECIFIC. The information equivalent to
2859 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2860 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
2861 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2862 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2864 /* Since a template declaration already existed for this
2865 class-type, we must be redeclaring it here. Make sure
2866 that the redeclaration is valid. */
2867 redeclare_class_template (TREE_TYPE (decl),
2868 current_template_parms);
2869 /* We don't need to create a new TEMPLATE_DECL; just use the
2870 one we already had. */
2871 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2875 tmpl = build_template_decl (decl, current_template_parms);
2878 if (DECL_LANG_SPECIFIC (decl)
2879 && DECL_TEMPLATE_SPECIALIZATION (decl))
2881 /* A specialization of a member template of a template
2883 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2884 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
2885 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
2891 tree a, t, current, parms;
2894 if (TREE_CODE (decl) == TYPE_DECL)
2896 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
2897 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
2898 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2899 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2900 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2903 error ("`%D' does not declare a template type", decl);
2907 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
2909 error ("template definition of non-template `%#D'", decl);
2913 tmpl = DECL_TI_TEMPLATE (decl);
2915 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
2916 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
2917 && DECL_TEMPLATE_SPECIALIZATION (decl)
2918 && is_member_template (tmpl))
2922 /* The declaration is a specialization of a member
2923 template, declared outside the class. Therefore, the
2924 innermost template arguments will be NULL, so we
2925 replace them with the arguments determined by the
2926 earlier call to check_explicit_specialization. */
2927 args = DECL_TI_ARGS (decl);
2930 = build_template_decl (decl, current_template_parms);
2931 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
2932 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
2933 DECL_TI_TEMPLATE (decl) = new_tmpl;
2934 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
2935 DECL_TEMPLATE_INFO (new_tmpl)
2936 = tree_cons (tmpl, args, NULL_TREE);
2938 register_specialization (new_tmpl,
2939 most_general_template (tmpl),
2944 /* Make sure the template headers we got make sense. */
2946 parms = DECL_TEMPLATE_PARMS (tmpl);
2947 i = TMPL_PARMS_DEPTH (parms);
2948 if (TMPL_ARGS_DEPTH (args) != i)
2950 error ("expected %d levels of template parms for `%#D', got %d",
2951 i, decl, TMPL_ARGS_DEPTH (args));
2954 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
2956 a = TMPL_ARGS_LEVEL (args, i);
2957 t = INNERMOST_TEMPLATE_PARMS (parms);
2959 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
2961 if (current == decl)
2962 error ("got %d template parameters for `%#D'",
2963 TREE_VEC_LENGTH (a), decl);
2965 error ("got %d template parameters for `%#T'",
2966 TREE_VEC_LENGTH (a), current);
2967 error (" but %d required", TREE_VEC_LENGTH (t));
2970 /* Perhaps we should also check that the parms are used in the
2971 appropriate qualifying scopes in the declarator? */
2973 if (current == decl)
2976 current = TYPE_CONTEXT (current);
2980 DECL_TEMPLATE_RESULT (tmpl) = decl;
2981 TREE_TYPE (tmpl) = TREE_TYPE (decl);
2983 /* Push template declarations for global functions and types. Note
2984 that we do not try to push a global template friend declared in a
2985 template class; such a thing may well depend on the template
2986 parameters of the class. */
2987 if (new_template_p && !ctx
2988 && !(is_friend && template_class_depth (current_class_type) > 0))
2989 tmpl = pushdecl_namespace_level (tmpl);
2993 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
2994 if (DECL_CONV_FN_P (tmpl))
2996 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2998 /* It is a conversion operator. See if the type converted to
2999 depends on innermost template operands. */
3001 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3003 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3007 /* The DECL_TI_ARGS of DECL contains full set of arguments refering
3008 back to its most general template. If TMPL is a specialization,
3009 ARGS may only have the innermost set of arguments. Add the missing
3010 argument levels if necessary. */
3011 if (DECL_TEMPLATE_INFO (tmpl))
3012 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3014 info = tree_cons (tmpl, args, NULL_TREE);
3016 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3018 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3019 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3020 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3021 /* Don't change the name if we've already set it up. */
3022 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3023 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3025 else if (DECL_LANG_SPECIFIC (decl))
3026 DECL_TEMPLATE_INFO (decl) = info;
3028 return DECL_TEMPLATE_RESULT (tmpl);
3032 push_template_decl (tree decl)
3034 return push_template_decl_real (decl, 0);
3037 /* Called when a class template TYPE is redeclared with the indicated
3038 template PARMS, e.g.:
3040 template <class T> struct S;
3041 template <class T> struct S {}; */
3044 redeclare_class_template (tree type, tree parms)
3050 if (!TYPE_TEMPLATE_INFO (type))
3052 error ("`%T' is not a template type", type);
3056 tmpl = TYPE_TI_TEMPLATE (type);
3057 if (!PRIMARY_TEMPLATE_P (tmpl))
3058 /* The type is nested in some template class. Nothing to worry
3059 about here; there are no new template parameters for the nested
3063 parms = INNERMOST_TEMPLATE_PARMS (parms);
3064 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3066 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3068 cp_error_at ("previous declaration `%D'", tmpl);
3069 error ("used %d template parameter%s instead of %d",
3070 TREE_VEC_LENGTH (tmpl_parms),
3071 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
3072 TREE_VEC_LENGTH (parms));
3076 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3078 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3079 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3080 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3081 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3083 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm))
3085 cp_error_at ("template parameter `%#D'", tmpl_parm);
3086 error ("redeclared here as `%#D'", parm);
3090 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3092 /* We have in [temp.param]:
3094 A template-parameter may not be given default arguments
3095 by two different declarations in the same scope. */
3096 error ("redefinition of default argument for `%#D'", parm);
3097 error ("%J original definition appeared here", tmpl_parm);
3101 if (parm_default != NULL_TREE)
3102 /* Update the previous template parameters (which are the ones
3103 that will really count) with the new default value. */
3104 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3105 else if (tmpl_default != NULL_TREE)
3106 /* Update the new parameters, too; they'll be used as the
3107 parameters for any members. */
3108 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3112 /* Simplify EXPR if it is a non-dependent expression. Returns the
3113 (possibly simplified) expression. */
3116 fold_non_dependent_expr (tree expr)
3118 /* If we're in a template, but EXPR isn't value dependent, simplify
3119 it. We're supposed to treat:
3121 template <typename T> void f(T[1 + 1]);
3122 template <typename T> void f(T[2]);
3124 as two declarations of the same function, for example. */
3125 if (processing_template_decl
3126 && !type_dependent_expression_p (expr)
3127 && !value_dependent_expression_p (expr))
3129 HOST_WIDE_INT saved_processing_template_decl;
3131 saved_processing_template_decl = processing_template_decl;
3132 processing_template_decl = 0;
3133 expr = tsubst_copy_and_build (expr,
3136 /*in_decl=*/NULL_TREE,
3137 /*function_p=*/false);
3138 processing_template_decl = saved_processing_template_decl;
3143 /* Attempt to convert the non-type template parameter EXPR to the
3144 indicated TYPE. If the conversion is successful, return the
3145 converted value. If the conversion is unsuccessful, return
3146 NULL_TREE if we issued an error message, or error_mark_node if we
3147 did not. We issue error messages for out-and-out bad template
3148 parameters, but not simply because the conversion failed, since we
3149 might be just trying to do argument deduction. Both TYPE and EXPR
3150 must be non-dependent. */
3153 convert_nontype_argument (tree type, tree expr)
3157 /* If we are in a template, EXPR may be non-dependent, but still
3158 have a syntactic, rather than semantic, form. For example, EXPR
3159 might be a SCOPE_REF, rather than the VAR_DECL to which the
3160 SCOPE_REF refers. Preserving the qualifying scope is necessary
3161 so that access checking can be performed when the template is
3162 instantiated -- but here we need the resolved form so that we can
3163 convert the argument. */
3164 expr = fold_non_dependent_expr (expr);
3165 expr_type = TREE_TYPE (expr);
3167 /* A template-argument for a non-type, non-template
3168 template-parameter shall be one of:
3170 --an integral constant-expression of integral or enumeration
3173 --the name of a non-type template-parameter; or
3175 --the name of an object or function with external linkage,
3176 including function templates and function template-ids but
3177 excluding non-static class members, expressed as id-expression;
3180 --the address of an object or function with external linkage,
3181 including function templates and function template-ids but
3182 excluding non-static class members, expressed as & id-expression
3183 where the & is optional if the name refers to a function or
3186 --a pointer to member expressed as described in _expr.unary.op_. */
3188 /* An integral constant-expression can include const variables or
3189 . enumerators. Simplify things by folding them to their values,
3190 unless we're about to bind the declaration to a reference
3192 if (INTEGRAL_TYPE_P (expr_type) && TREE_CODE (type) != REFERENCE_TYPE)
3195 tree const_expr = decl_constant_value (expr);
3196 /* In a template, the initializer for a VAR_DECL may not be
3197 marked as TREE_CONSTANT, in which case decl_constant_value
3198 will not return the initializer. Handle that special case
3200 if (expr == const_expr
3201 && TREE_CODE (expr) == VAR_DECL
3202 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (expr)
3203 && CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (expr))
3204 /* DECL_INITIAL can be NULL if we are processing a
3205 variable initialized to an expression involving itself.
3206 We know it is initialized to a constant -- but not what
3208 && DECL_INITIAL (expr))
3209 const_expr = DECL_INITIAL (expr);
3210 if (expr == const_expr)
3212 expr = fold_non_dependent_expr (const_expr);
3215 if (is_overloaded_fn (expr))
3216 /* OK for now. We'll check that it has external linkage later.
3217 Check this first since if expr_type is the unknown_type_node
3218 we would otherwise complain below. */
3220 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3222 if (TREE_CODE (expr) != PTRMEM_CST)
3225 else if (TYPE_PTR_P (expr_type)
3226 || TREE_CODE (expr_type) == ARRAY_TYPE
3227 || TREE_CODE (type) == REFERENCE_TYPE
3228 /* If expr is the address of an overloaded function, we
3229 will get the unknown_type_node at this point. */
3230 || expr_type == unknown_type_node)
3236 if (TREE_CODE (expr_type) == ARRAY_TYPE
3237 || (TREE_CODE (type) == REFERENCE_TYPE
3238 && TREE_CODE (e) != ADDR_EXPR))
3242 if (TREE_CODE (e) != ADDR_EXPR)
3245 error ("`%E' is not a valid template argument", expr);
3246 if (TYPE_PTR_P (expr_type))
3248 if (TREE_CODE (TREE_TYPE (expr_type)) == FUNCTION_TYPE)
3249 error ("it must be the address of a function with external linkage");
3251 error ("it must be the address of an object with external linkage");
3253 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3254 error ("it must be a pointer-to-member of the form `&X::Y'");
3259 referent = TREE_OPERAND (e, 0);
3260 STRIP_NOPS (referent);
3263 if (TREE_CODE (referent) == STRING_CST)
3265 error ("string literal %E is not a valid template argument because it is the address of an object with static linkage",
3270 if (TREE_CODE (referent) == SCOPE_REF)
3271 referent = TREE_OPERAND (referent, 1);
3273 if (is_overloaded_fn (referent))
3274 /* We'll check that it has external linkage later. */
3276 else if (TREE_CODE (referent) != VAR_DECL)
3278 else if (!DECL_EXTERNAL_LINKAGE_P (referent))
3280 error ("address of non-extern `%E' cannot be used as template argument", referent);
3281 return error_mark_node;
3284 else if (INTEGRAL_TYPE_P (expr_type) || TYPE_PTR_TO_MEMBER_P (expr_type))
3286 if (! TREE_CONSTANT (expr))
3289 error ("non-constant `%E' cannot be used as template argument",
3297 error ("type '%T' cannot be used as a value for a non-type "
3298 "template-parameter", expr);
3299 else if (DECL_P (expr))
3300 error ("invalid use of '%D' as a non-type template-argument", expr);
3302 error ("invalid use of '%E' as a non-type template-argument", expr);
3307 switch (TREE_CODE (type))
3312 /* For a non-type template-parameter of integral or enumeration
3313 type, integral promotions (_conv.prom_) and integral
3314 conversions (_conv.integral_) are applied. */
3315 if (!INTEGRAL_TYPE_P (expr_type))
3316 return error_mark_node;
3318 /* It's safe to call digest_init in this case; we know we're
3319 just converting one integral constant expression to another. */
3320 expr = digest_init (type, expr, (tree*) 0);
3322 if (TREE_CODE (expr) != INTEGER_CST)
3323 /* Curiously, some TREE_CONSTANT integral expressions do not
3324 simplify to integer constants. For example, `3 % 0',
3325 remains a TRUNC_MOD_EXPR. */
3334 /* For a non-type template-parameter of type pointer to data
3335 member, qualification conversions (_conv.qual_) are
3337 e = perform_qualification_conversions (type, expr);
3338 if (TREE_CODE (e) == NOP_EXPR)
3339 /* The call to perform_qualification_conversions will
3340 insert a NOP_EXPR over EXPR to do express conversion,
3341 if necessary. But, that will confuse us if we use
3342 this (converted) template parameter to instantiate
3343 another template; then the thing will not look like a
3344 valid template argument. So, just make a new
3345 constant, of the appropriate type. */
3346 e = make_ptrmem_cst (type, PTRMEM_CST_MEMBER (expr));
3352 tree type_pointed_to = TREE_TYPE (type);
3354 if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE)
3356 /* For a non-type template-parameter of type pointer to
3357 function, only the function-to-pointer conversion
3358 (_conv.func_) is applied. If the template-argument
3359 represents a set of overloaded functions (or a pointer to
3360 such), the matching function is selected from the set
3365 if (TREE_CODE (expr) == ADDR_EXPR)
3366 fns = TREE_OPERAND (expr, 0);
3370 fn = instantiate_type (type_pointed_to, fns, tf_none);
3372 if (fn == error_mark_node)
3373 return error_mark_node;
3375 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3377 if (really_overloaded_fn (fns))
3378 return error_mark_node;
3383 expr = build_unary_op (ADDR_EXPR, fn, 0);
3385 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3391 /* For a non-type template-parameter of type pointer to
3392 object, qualification conversions (_conv.qual_) and the
3393 array-to-pointer conversion (_conv.array_) are applied.
3394 [Note: In particular, neither the null pointer conversion
3395 (_conv.ptr_) nor the derived-to-base conversion
3396 (_conv.ptr_) are applied. Although 0 is a valid
3397 template-argument for a non-type template-parameter of
3398 integral type, it is not a valid template-argument for a
3399 non-type template-parameter of pointer type.]
3401 The call to decay_conversion performs the
3402 array-to-pointer conversion, if appropriate. */
3403 expr = decay_conversion (expr);
3405 if (expr == error_mark_node)
3406 return error_mark_node;
3408 return perform_qualification_conversions (type, expr);
3413 case REFERENCE_TYPE:
3415 tree type_referred_to = TREE_TYPE (type);
3417 /* If this expression already has reference type, get the
3418 underlying object. */
3419 if (TREE_CODE (expr_type) == REFERENCE_TYPE)
3421 if (TREE_CODE (expr) == NOP_EXPR
3422 && TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR)
3424 my_friendly_assert (TREE_CODE (expr) == ADDR_EXPR, 20000604);
3425 expr = TREE_OPERAND (expr, 0);
3426 expr_type = TREE_TYPE (expr);
3429 if (TREE_CODE (type_referred_to) == FUNCTION_TYPE)
3431 /* For a non-type template-parameter of type reference to
3432 function, no conversions apply. If the
3433 template-argument represents a set of overloaded
3434 functions, the matching function is selected from the
3435 set (_over.over_). */
3438 fn = instantiate_type (type_referred_to, expr, tf_none);
3440 if (fn == error_mark_node)
3441 return error_mark_node;
3443 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3445 if (really_overloaded_fn (expr))
3446 /* Don't issue an error here; we might get a different
3447 function if the overloading had worked out
3449 return error_mark_node;
3454 my_friendly_assert (same_type_p (type_referred_to,
3462 /* For a non-type template-parameter of type reference to
3463 object, no conversions apply. The type referred to by the
3464 reference may be more cv-qualified than the (otherwise
3465 identical) type of the template-argument. The
3466 template-parameter is bound directly to the
3467 template-argument, which must be an lvalue. */
3468 if (!same_type_p (TYPE_MAIN_VARIANT (expr_type),
3469 TYPE_MAIN_VARIANT (type_referred_to))
3470 || !at_least_as_qualified_p (type_referred_to,
3472 || !real_lvalue_p (expr))
3473 return error_mark_node;
3476 cxx_mark_addressable (expr);
3477 return build_nop (type, build_address (expr));
3483 my_friendly_assert (TYPE_PTRMEMFUNC_P (type), 20010112);
3485 /* For a non-type template-parameter of type pointer to member
3486 function, no conversions apply. If the template-argument
3487 represents a set of overloaded member functions, the
3488 matching member function is selected from the set
3491 if (!TYPE_PTRMEMFUNC_P (expr_type) &&
3492 expr_type != unknown_type_node)
3493 return error_mark_node;
3495 if (TREE_CODE (expr) == PTRMEM_CST)
3497 /* A ptr-to-member constant. */
3498 if (!same_type_p (type, expr_type))
3499 return error_mark_node;
3504 if (TREE_CODE (expr) != ADDR_EXPR)
3505 return error_mark_node;
3507 expr = instantiate_type (type, expr, tf_none);
3509 if (expr == error_mark_node)
3510 return error_mark_node;
3512 if (!same_type_p (type, TREE_TYPE (expr)))
3513 return error_mark_node;
3520 /* All non-type parameters must have one of these types. */
3525 return error_mark_node;
3528 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3529 template template parameters. Both PARM_PARMS and ARG_PARMS are
3530 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3533 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3534 the case, then extra parameters must have default arguments.
3536 Consider the example:
3537 template <class T, class Allocator = allocator> class vector;
3538 template<template <class U> class TT> class C;
3540 C<vector> is a valid instantiation. PARM_PARMS for the above code
3541 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3542 T and Allocator) and OUTER_ARGS contains the argument that is used to
3543 substitute the TT parameter. */
3546 coerce_template_template_parms (tree parm_parms,
3548 tsubst_flags_t complain,
3552 int nparms, nargs, i;
3555 my_friendly_assert (TREE_CODE (parm_parms) == TREE_VEC, 0);
3556 my_friendly_assert (TREE_CODE (arg_parms) == TREE_VEC, 0);
3558 nparms = TREE_VEC_LENGTH (parm_parms);
3559 nargs = TREE_VEC_LENGTH (arg_parms);
3561 /* The rule here is opposite of coerce_template_parms. */
3564 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3567 for (i = 0; i < nparms; ++i)
3569 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3570 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3572 if (arg == NULL_TREE || arg == error_mark_node
3573 || parm == NULL_TREE || parm == error_mark_node)
3576 if (TREE_CODE (arg) != TREE_CODE (parm))
3579 switch (TREE_CODE (parm))
3585 /* We encounter instantiations of templates like
3586 template <template <template <class> class> class TT>
3589 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3590 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3592 if (!coerce_template_template_parms
3593 (parmparm, argparm, complain, in_decl, outer_args))
3599 /* The tsubst call is used to handle cases such as
3600 template <class T, template <T> class TT> class D;
3601 i.e. the parameter list of TT depends on earlier parameters. */
3603 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3615 /* Convert the indicated template ARG as necessary to match the
3616 indicated template PARM. Returns the converted ARG, or
3617 error_mark_node if the conversion was unsuccessful. Error and
3618 warning messages are issued under control of COMPLAIN. This
3619 conversion is for the Ith parameter in the parameter list. ARGS is
3620 the full set of template arguments deduced so far. */
3623 convert_template_argument (tree parm,
3626 tsubst_flags_t complain,
3632 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3634 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3636 if (TREE_CODE (arg) == TREE_LIST
3637 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3639 /* The template argument was the name of some
3640 member function. That's usually
3641 invalid, but static members are OK. In any
3642 case, grab the underlying fields/functions
3643 and issue an error later if required. */
3644 arg = TREE_VALUE (arg);
3645 TREE_TYPE (arg) = unknown_type_node;
3648 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3649 requires_type = (TREE_CODE (parm) == TYPE_DECL
3650 || requires_tmpl_type);
3652 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3653 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3654 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3655 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3658 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3659 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3660 arg = TYPE_STUB_DECL (arg);
3662 is_type = TYPE_P (arg) || is_tmpl_type;
3664 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3665 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3667 pedwarn ("to refer to a type member of a template parameter, use `typename %E'", arg);
3669 arg = make_typename_type (TREE_OPERAND (arg, 0),
3670 TREE_OPERAND (arg, 1),
3671 complain & tf_error);
3674 if (is_type != requires_type)
3678 if (complain & tf_error)
3680 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3683 error (" expected a constant of type `%T', got `%T'",
3685 (is_tmpl_type ? DECL_NAME (arg) : arg));
3686 else if (requires_tmpl_type)
3687 error (" expected a class template, got `%E'", arg);
3689 error (" expected a type, got `%E'", arg);
3692 return error_mark_node;
3694 if (is_tmpl_type ^ requires_tmpl_type)
3696 if (in_decl && (complain & tf_error))
3698 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3701 error (" expected a type, got `%T'", DECL_NAME (arg));
3703 error (" expected a class template, got `%T'", arg);
3705 return error_mark_node;
3710 if (requires_tmpl_type)
3712 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3713 /* The number of argument required is not known yet.
3714 Just accept it for now. */
3715 val = TREE_TYPE (arg);
3718 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3719 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3721 if (coerce_template_template_parms (parmparm, argparm,
3727 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3729 if (val != error_mark_node
3730 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3731 val = TREE_TYPE (val);
3735 if (in_decl && (complain & tf_error))
3737 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3739 error (" expected a template of type `%D', got `%D'", parm, arg);
3742 val = error_mark_node;
3747 val = groktypename (arg);
3751 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3753 if (invalid_nontype_parm_type_p (t, complain))
3754 return error_mark_node;
3756 if (!uses_template_parms (arg) && !uses_template_parms (t))
3757 /* We used to call digest_init here. However, digest_init
3758 will report errors, which we don't want when complain
3759 is zero. More importantly, digest_init will try too
3760 hard to convert things: for example, `0' should not be
3761 converted to pointer type at this point according to
3762 the standard. Accepting this is not merely an
3763 extension, since deciding whether or not these
3764 conversions can occur is part of determining which
3765 function template to call, or whether a given explicit
3766 argument specification is valid. */
3767 val = convert_nontype_argument (t, arg);
3771 if (val == NULL_TREE)
3772 val = error_mark_node;
3773 else if (val == error_mark_node && (complain & tf_error))
3774 error ("could not convert template argument `%E' to `%T'",
3781 /* Convert all template arguments to their appropriate types, and
3782 return a vector containing the innermost resulting template
3783 arguments. If any error occurs, return error_mark_node. Error and
3784 warning messages are issued under control of COMPLAIN.
3786 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3787 provided in ARGLIST, or else trailing parameters must have default
3788 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3789 deduction for any unspecified trailing arguments. */
3792 coerce_template_parms (tree parms,
3795 tsubst_flags_t complain,
3796 int require_all_arguments)
3798 int nparms, nargs, i, lost = 0;
3801 tree new_inner_args;
3803 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3804 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3805 nparms = TREE_VEC_LENGTH (parms);
3809 && require_all_arguments
3810 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3812 if (complain & tf_error)
3814 error ("wrong number of template arguments (%d, should be %d)",
3818 cp_error_at ("provided for `%D'", in_decl);
3821 return error_mark_node;
3824 new_inner_args = make_tree_vec (nparms);
3825 new_args = add_outermost_template_args (args, new_inner_args);
3826 for (i = 0; i < nparms; i++)
3831 /* Get the Ith template parameter. */
3832 parm = TREE_VEC_ELT (parms, i);
3834 /* Calculate the Ith argument. */
3836 arg = TREE_VEC_ELT (inner_args, i);
3837 else if (require_all_arguments)
3838 /* There must be a default arg in this case. */
3839 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
3844 my_friendly_assert (arg, 20030727);
3845 if (arg == error_mark_node)
3846 error ("template argument %d is invalid", i + 1);
3848 arg = convert_template_argument (TREE_VALUE (parm),
3849 arg, new_args, complain, i,
3852 if (arg == error_mark_node)
3854 TREE_VEC_ELT (new_inner_args, i) = arg;
3858 return error_mark_node;
3860 return new_inner_args;
3863 /* Returns 1 if template args OT and NT are equivalent. */
3866 template_args_equal (tree ot, tree nt)
3871 if (TREE_CODE (nt) == TREE_VEC)
3872 /* For member templates */
3873 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
3874 else if (TYPE_P (nt))
3875 return TYPE_P (ot) && same_type_p (ot, nt);
3876 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
3879 return cp_tree_equal (ot, nt);
3882 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
3883 of template arguments. Returns 0 otherwise. */
3886 comp_template_args (tree oldargs, tree newargs)
3890 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
3893 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
3895 tree nt = TREE_VEC_ELT (newargs, i);
3896 tree ot = TREE_VEC_ELT (oldargs, i);
3898 if (! template_args_equal (ot, nt))
3904 /* Given class template name and parameter list, produce a user-friendly name
3905 for the instantiation. */
3908 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
3910 static struct obstack scratch_obstack;
3911 static char *scratch_firstobj;
3914 if (!scratch_firstobj)
3915 gcc_obstack_init (&scratch_obstack);
3917 obstack_free (&scratch_obstack, scratch_firstobj);
3918 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
3920 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
3921 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
3925 nparms = TREE_VEC_LENGTH (parms);
3926 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
3927 my_friendly_assert (nparms == TREE_VEC_LENGTH (arglist), 268);
3928 for (i = 0; i < nparms; i++)
3930 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3931 tree arg = TREE_VEC_ELT (arglist, i);
3936 if (TREE_CODE (parm) == TYPE_DECL)
3938 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
3941 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3943 if (TREE_CODE (arg) == TEMPLATE_DECL)
3945 /* Already substituted with real template. Just output
3946 the template name here */
3947 tree context = DECL_CONTEXT (arg);
3950 /* The template may be defined in a namespace, or
3951 may be a member template. */
3952 my_friendly_assert (TREE_CODE (context) == NAMESPACE_DECL
3953 || CLASS_TYPE_P (context),
3955 cat(decl_as_string (DECL_CONTEXT (arg), TFF_PLAIN_IDENTIFIER));
3958 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
3961 /* Output the parameter declaration. */
3962 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
3966 my_friendly_assert (TREE_CODE (parm) == PARM_DECL, 269);
3968 /* No need to check arglist against parmlist here; we did that
3969 in coerce_template_parms, called from lookup_template_class. */
3970 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
3973 char *bufp = obstack_next_free (&scratch_obstack);
3975 while (bufp[offset - 1] == ' ')
3977 obstack_blank_fast (&scratch_obstack, offset);
3979 /* B<C<char> >, not B<C<char>> */
3980 if (bufp[offset - 1] == '>')
3985 return (char *) obstack_base (&scratch_obstack);
3989 classtype_mangled_name (tree t)
3991 if (CLASSTYPE_TEMPLATE_INFO (t)
3992 /* Specializations have already had their names set up in
3993 lookup_template_class. */
3994 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
3996 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
3998 /* For non-primary templates, the template parameters are
3999 implicit from their surrounding context. */
4000 if (PRIMARY_TEMPLATE_P (tmpl))
4002 tree name = DECL_NAME (tmpl);
4003 char *mangled_name = mangle_class_name_for_template
4004 (IDENTIFIER_POINTER (name),
4005 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4006 CLASSTYPE_TI_ARGS (t));
4007 tree id = get_identifier (mangled_name);
4008 IDENTIFIER_TEMPLATE (id) = name;
4013 return TYPE_IDENTIFIER (t);
4017 add_pending_template (tree d)
4019 tree ti = (TYPE_P (d)
4020 ? CLASSTYPE_TEMPLATE_INFO (d)
4021 : DECL_TEMPLATE_INFO (d));
4025 if (TI_PENDING_TEMPLATE_FLAG (ti))
4028 /* We are called both from instantiate_decl, where we've already had a
4029 tinst_level pushed, and instantiate_template, where we haven't.
4031 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4034 push_tinst_level (d);
4036 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4037 if (last_pending_template)
4038 TREE_CHAIN (last_pending_template) = pt;
4040 pending_templates = pt;
4042 last_pending_template = pt;
4044 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4051 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4052 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4053 documentation for TEMPLATE_ID_EXPR. */
4056 lookup_template_function (tree fns, tree arglist)
4060 if (fns == error_mark_node || arglist == error_mark_node)
4061 return error_mark_node;
4063 my_friendly_assert (!arglist || TREE_CODE (arglist) == TREE_VEC, 20030726);
4064 if (fns == NULL_TREE
4065 || TREE_CODE (fns) == FUNCTION_DECL)
4067 error ("non-template used as template");
4068 return error_mark_node;
4071 my_friendly_assert (TREE_CODE (fns) == TEMPLATE_DECL
4072 || TREE_CODE (fns) == OVERLOAD
4074 || TREE_CODE (fns) == IDENTIFIER_NODE,
4077 if (BASELINK_P (fns))
4079 BASELINK_FUNCTIONS (fns) = build (TEMPLATE_ID_EXPR,
4081 BASELINK_FUNCTIONS (fns),
4086 type = TREE_TYPE (fns);
4087 if (TREE_CODE (fns) == OVERLOAD || !type)
4088 type = unknown_type_node;
4090 return build (TEMPLATE_ID_EXPR, type, fns, arglist);
4093 /* Within the scope of a template class S<T>, the name S gets bound
4094 (in build_self_reference) to a TYPE_DECL for the class, not a
4095 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4096 or one of its enclosing classes, and that type is a template,
4097 return the associated TEMPLATE_DECL. Otherwise, the original
4098 DECL is returned. */
4101 maybe_get_template_decl_from_type_decl (tree decl)
4103 return (decl != NULL_TREE
4104 && TREE_CODE (decl) == TYPE_DECL
4105 && DECL_ARTIFICIAL (decl)
4106 && CLASS_TYPE_P (TREE_TYPE (decl))
4107 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4108 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4111 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4112 parameters, find the desired type.
4114 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4116 IN_DECL, if non-NULL, is the template declaration we are trying to
4119 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4120 the class we are looking up.
4122 Issue error and warning messages under control of COMPLAIN.
4124 If the template class is really a local class in a template
4125 function, then the FUNCTION_CONTEXT is the function in which it is
4126 being instantiated. */
4129 lookup_template_class (tree d1,
4134 tsubst_flags_t complain)
4136 tree template = NULL_TREE, parmlist;
4139 timevar_push (TV_NAME_LOOKUP);
4141 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4143 if (IDENTIFIER_VALUE (d1)
4144 && DECL_TEMPLATE_TEMPLATE_PARM_P (IDENTIFIER_VALUE (d1)))
4145 template = IDENTIFIER_VALUE (d1);
4149 push_decl_namespace (context);
4150 template = lookup_name (d1, /*prefer_type=*/0);
4151 template = maybe_get_template_decl_from_type_decl (template);
4153 pop_decl_namespace ();
4156 context = DECL_CONTEXT (template);
4158 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4160 tree type = TREE_TYPE (d1);
4162 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4163 an implicit typename for the second A. Deal with it. */
4164 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4165 type = TREE_TYPE (type);
4167 if (CLASSTYPE_TEMPLATE_INFO (type))
4169 template = CLASSTYPE_TI_TEMPLATE (type);
4170 d1 = DECL_NAME (template);
4173 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4174 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4176 template = TYPE_TI_TEMPLATE (d1);
4177 d1 = DECL_NAME (template);
4179 else if (TREE_CODE (d1) == TEMPLATE_DECL
4180 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4183 d1 = DECL_NAME (template);
4184 context = DECL_CONTEXT (template);
4187 /* With something like `template <class T> class X class X { ... };'
4188 we could end up with D1 having nothing but an IDENTIFIER_VALUE.
4189 We don't want to do that, but we have to deal with the situation,
4190 so let's give them some syntax errors to chew on instead of a
4191 crash. Alternatively D1 might not be a template type at all. */
4194 if (complain & tf_error)
4195 error ("`%T' is not a template", d1);
4196 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4199 if (TREE_CODE (template) != TEMPLATE_DECL
4200 /* Make sure it's a user visible template, if it was named by
4202 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4203 && !PRIMARY_TEMPLATE_P (template)))
4205 if (complain & tf_error)
4207 error ("non-template type `%T' used as a template", d1);
4209 cp_error_at ("for template declaration `%D'", in_decl);
4211 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4214 complain &= ~tf_user;
4216 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4218 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4219 template arguments */
4224 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4226 /* Consider an example where a template template parameter declared as
4228 template <class T, class U = std::allocator<T> > class TT
4230 The template parameter level of T and U are one level larger than
4231 of TT. To proper process the default argument of U, say when an
4232 instantiation `TT<int>' is seen, we need to build the full
4233 arguments containing {int} as the innermost level. Outer levels,
4234 available when not appearing as default template argument, can be
4235 obtained from `current_template_args ()'.
4237 Suppose that TT is later substituted with std::vector. The above
4238 instantiation is `TT<int, std::allocator<T> >' with TT at
4239 level 1, and T at level 2, while the template arguments at level 1
4240 becomes {std::vector} and the inner level 2 is {int}. */
4242 if (current_template_parms)
4243 arglist = add_to_template_args (current_template_args (), arglist);
4245 arglist2 = coerce_template_parms (parmlist, arglist, template,
4246 complain, /*require_all_args=*/1);
4247 if (arglist2 == error_mark_node
4248 || (!uses_template_parms (arglist2)
4249 && check_instantiated_args (template, arglist2, complain)))
4250 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4252 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4253 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4257 tree template_type = TREE_TYPE (template);
4260 tree found = NULL_TREE;
4264 int is_partial_instantiation;
4266 gen_tmpl = most_general_template (template);
4267 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4268 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4269 arg_depth = TMPL_ARGS_DEPTH (arglist);
4271 if (arg_depth == 1 && parm_depth > 1)
4273 /* We've been given an incomplete set of template arguments.
4276 template <class T> struct S1 {
4277 template <class U> struct S2 {};
4278 template <class U> struct S2<U*> {};
4281 we will be called with an ARGLIST of `U*', but the
4282 TEMPLATE will be `template <class T> template
4283 <class U> struct S1<T>::S2'. We must fill in the missing
4286 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4288 arg_depth = TMPL_ARGS_DEPTH (arglist);
4291 /* Now we should have enough arguments. */
4292 my_friendly_assert (parm_depth == arg_depth, 0);
4294 /* From here on, we're only interested in the most general
4296 template = gen_tmpl;
4298 /* Calculate the BOUND_ARGS. These will be the args that are
4299 actually tsubst'd into the definition to create the
4303 /* We have multiple levels of arguments to coerce, at once. */
4305 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4307 tree bound_args = make_tree_vec (parm_depth);
4309 for (i = saved_depth,
4310 t = DECL_TEMPLATE_PARMS (template);
4311 i > 0 && t != NULL_TREE;
4312 --i, t = TREE_CHAIN (t))
4314 tree a = coerce_template_parms (TREE_VALUE (t),
4316 complain, /*require_all_args=*/1);
4318 /* Don't process further if one of the levels fails. */
4319 if (a == error_mark_node)
4321 /* Restore the ARGLIST to its full size. */
4322 TREE_VEC_LENGTH (arglist) = saved_depth;
4323 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4326 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4328 /* We temporarily reduce the length of the ARGLIST so
4329 that coerce_template_parms will see only the arguments
4330 corresponding to the template parameters it is
4332 TREE_VEC_LENGTH (arglist)--;
4335 /* Restore the ARGLIST to its full size. */
4336 TREE_VEC_LENGTH (arglist) = saved_depth;
4338 arglist = bound_args;
4342 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4343 INNERMOST_TEMPLATE_ARGS (arglist),
4345 complain, /*require_all_args=*/1);
4347 if (arglist == error_mark_node)
4348 /* We were unable to bind the arguments. */
4349 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4351 /* In the scope of a template class, explicit references to the
4352 template class refer to the type of the template, not any
4353 instantiation of it. For example, in:
4355 template <class T> class C { void f(C<T>); }
4357 the `C<T>' is just the same as `C'. Outside of the
4358 class, however, such a reference is an instantiation. */
4359 if (comp_template_args (TYPE_TI_ARGS (template_type),
4362 found = template_type;
4364 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4368 for (ctx = current_class_type;
4369 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4371 ? TYPE_CONTEXT (ctx)
4372 : DECL_CONTEXT (ctx)))
4373 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4376 /* We're not in the scope of the class, so the
4377 TEMPLATE_TYPE is not the type we want after all. */
4383 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4385 for (tp = &DECL_TEMPLATE_INSTANTIATIONS (template);
4387 tp = &TREE_CHAIN (*tp))
4388 if (comp_template_args (TREE_PURPOSE (*tp), arglist))
4392 /* Use the move-to-front heuristic to speed up future
4394 *tp = TREE_CHAIN (*tp);
4396 = DECL_TEMPLATE_INSTANTIATIONS (template);
4397 DECL_TEMPLATE_INSTANTIATIONS (template) = found;
4399 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, TREE_VALUE (found));
4402 /* This type is a "partial instantiation" if any of the template
4403 arguments still involve template parameters. Note that we set
4404 IS_PARTIAL_INSTANTIATION for partial specializations as
4406 is_partial_instantiation = uses_template_parms (arglist);
4408 /* If the deduced arguments are invalid, then the binding
4410 if (!is_partial_instantiation
4411 && check_instantiated_args (template,
4412 INNERMOST_TEMPLATE_ARGS (arglist),
4414 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4416 if (!is_partial_instantiation
4417 && !PRIMARY_TEMPLATE_P (template)
4418 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4420 found = xref_tag_from_type (TREE_TYPE (template),
4421 DECL_NAME (template),
4423 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4426 context = tsubst (DECL_CONTEXT (template), arglist,
4429 context = global_namespace;
4431 /* Create the type. */
4432 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4434 if (!is_partial_instantiation)
4436 set_current_access_from_decl (TYPE_NAME (template_type));
4437 t = start_enum (TYPE_IDENTIFIER (template_type));
4440 /* We don't want to call start_enum for this type, since
4441 the values for the enumeration constants may involve
4442 template parameters. And, no one should be interested
4443 in the enumeration constants for such a type. */
4444 t = make_node (ENUMERAL_TYPE);
4448 t = make_aggr_type (TREE_CODE (template_type));
4449 CLASSTYPE_DECLARED_CLASS (t)
4450 = CLASSTYPE_DECLARED_CLASS (template_type);
4451 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4452 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4454 /* A local class. Make sure the decl gets registered properly. */
4455 if (context == current_function_decl)
4456 pushtag (DECL_NAME (template), t, 0);
4459 /* If we called start_enum or pushtag above, this information
4460 will already be set up. */
4463 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4465 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4466 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4467 TYPE_STUB_DECL (t) = type_decl;
4468 DECL_SOURCE_LOCATION (type_decl)
4469 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4472 type_decl = TYPE_NAME (t);
4474 TREE_PRIVATE (type_decl)
4475 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4476 TREE_PROTECTED (type_decl)
4477 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4479 /* Set up the template information. We have to figure out which
4480 template is the immediate parent if this is a full
4482 if (parm_depth == 1 || is_partial_instantiation
4483 || !PRIMARY_TEMPLATE_P (template))
4484 /* This case is easy; there are no member templates involved. */
4488 /* This is a full instantiation of a member template. Look
4489 for a partial instantiation of which this is an instance. */
4491 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4492 found; found = TREE_CHAIN (found))
4495 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4497 /* We only want partial instantiations, here, not
4498 specializations or full instantiations. */
4499 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4500 || !uses_template_parms (TREE_VALUE (found)))
4503 /* Temporarily reduce by one the number of levels in the
4504 ARGLIST and in FOUND so as to avoid comparing the
4505 last set of arguments. */
4506 TREE_VEC_LENGTH (arglist)--;
4507 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4509 /* See if the arguments match. If they do, then TMPL is
4510 the partial instantiation we want. */
4511 success = comp_template_args (TREE_PURPOSE (found), arglist);
4513 /* Restore the argument vectors to their full size. */
4514 TREE_VEC_LENGTH (arglist)++;
4515 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4526 /* There was no partial instantiation. This happens
4527 where C<T> is a member template of A<T> and it's used
4530 template <typename T> struct B { A<T>::C<int> m; };
4533 Create the partial instantiation.
4535 TREE_VEC_LENGTH (arglist)--;
4536 found = tsubst (template, arglist, complain, NULL_TREE);
4537 TREE_VEC_LENGTH (arglist)++;
4541 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4542 DECL_TEMPLATE_INSTANTIATIONS (template)
4543 = tree_cons (arglist, t,
4544 DECL_TEMPLATE_INSTANTIATIONS (template));
4546 if (TREE_CODE (t) == ENUMERAL_TYPE
4547 && !is_partial_instantiation)
4548 /* Now that the type has been registered on the instantiations
4549 list, we set up the enumerators. Because the enumeration
4550 constants may involve the enumeration type itself, we make
4551 sure to register the type first, and then create the
4552 constants. That way, doing tsubst_expr for the enumeration
4553 constants won't result in recursive calls here; we'll find
4554 the instantiation and exit above. */
4555 tsubst_enum (template_type, t, arglist);
4557 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4559 if (TREE_CODE (t) != ENUMERAL_TYPE)
4560 DECL_NAME (type_decl) = classtype_mangled_name (t);
4561 if (is_partial_instantiation)
4562 /* If the type makes use of template parameters, the
4563 code that generates debugging information will crash. */
4564 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4566 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4568 timevar_pop (TV_NAME_LOOKUP);
4578 /* Called from for_each_template_parm via walk_tree. */
4581 for_each_template_parm_r (tree* tp, int* walk_subtrees, void* d)
4584 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4585 tree_fn_t fn = pfd->fn;
4586 void *data = pfd->data;
4589 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4590 return error_mark_node;
4592 switch (TREE_CODE (t))
4595 if (TYPE_PTRMEMFUNC_P (t))
4601 if (!TYPE_TEMPLATE_INFO (t))
4603 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4604 fn, data, pfd->visited))
4605 return error_mark_node;
4609 /* Since we're not going to walk subtrees, we have to do this
4611 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4613 return error_mark_node;
4617 /* Check the return type. */
4618 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4619 return error_mark_node;
4621 /* Check the parameter types. Since default arguments are not
4622 instantiated until they are needed, the TYPE_ARG_TYPES may
4623 contain expressions that involve template parameters. But,
4624 no-one should be looking at them yet. And, once they're
4625 instantiated, they don't contain template parameters, so
4626 there's no point in looking at them then, either. */
4630 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4631 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4633 return error_mark_node;
4635 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4636 want walk_tree walking into them itself. */
4642 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4644 return error_mark_node;
4649 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4650 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4652 return error_mark_node;
4657 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4658 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4660 return error_mark_node;
4661 if (DECL_CONTEXT (t)
4662 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4664 return error_mark_node;
4667 case BOUND_TEMPLATE_TEMPLATE_PARM:
4668 /* Record template parameters such as `T' inside `TT<T>'. */
4669 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4670 return error_mark_node;
4673 case TEMPLATE_TEMPLATE_PARM:
4674 case TEMPLATE_TYPE_PARM:
4675 case TEMPLATE_PARM_INDEX:
4676 if (fn && (*fn)(t, data))
4677 return error_mark_node;
4679 return error_mark_node;
4683 /* A template template parameter is encountered. */
4684 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4685 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4686 return error_mark_node;
4688 /* Already substituted template template parameter */
4694 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4695 data, pfd->visited))
4696 return error_mark_node;
4700 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4701 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4702 (TREE_TYPE (t)), fn, data,
4704 return error_mark_node;
4709 /* If there's no type, then this thing must be some expression
4710 involving template parameters. */
4711 if (!fn && !TREE_TYPE (t))
4712 return error_mark_node;
4717 case REINTERPRET_CAST_EXPR:
4718 case CONST_CAST_EXPR:
4719 case STATIC_CAST_EXPR:
4720 case DYNAMIC_CAST_EXPR:
4724 case PSEUDO_DTOR_EXPR:
4726 return error_mark_node;
4730 /* If we do not handle this case specially, we end up walking
4731 the BINFO hierarchy, which is circular, and therefore
4732 confuses walk_tree. */
4734 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4736 return error_mark_node;
4743 /* We didn't find any template parameters we liked. */
4747 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4748 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4749 call FN with the parameter and the DATA.
4750 If FN returns nonzero, the iteration is terminated, and
4751 for_each_template_parm returns 1. Otherwise, the iteration
4752 continues. If FN never returns a nonzero value, the value
4753 returned by for_each_template_parm is 0. If FN is NULL, it is
4754 considered to be the function which always returns 1. */
4757 for_each_template_parm (tree t, tree_fn_t fn, void* data, htab_t visited)
4759 struct pair_fn_data pfd;
4766 /* Walk the tree. (Conceptually, we would like to walk without
4767 duplicates, but for_each_template_parm_r recursively calls
4768 for_each_template_parm, so we would need to reorganize a fair
4769 bit to use walk_tree_without_duplicates, so we keep our own
4772 pfd.visited = visited;
4774 pfd.visited = htab_create (37, htab_hash_pointer, htab_eq_pointer,
4776 result = walk_tree (&t,
4777 for_each_template_parm_r,
4779 pfd.visited) != NULL_TREE;
4783 htab_delete (pfd.visited);
4788 /* Returns true if T depends on any template parameter. */
4791 uses_template_parms (tree t)
4794 int saved_processing_template_decl;
4796 saved_processing_template_decl = processing_template_decl;
4797 if (!saved_processing_template_decl)
4798 processing_template_decl = 1;
4800 dependent_p = dependent_type_p (t);
4801 else if (TREE_CODE (t) == TREE_VEC)
4802 dependent_p = any_dependent_template_arguments_p (t);
4803 else if (TREE_CODE (t) == TREE_LIST)
4804 dependent_p = (uses_template_parms (TREE_VALUE (t))
4805 || uses_template_parms (TREE_CHAIN (t)));
4808 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4809 || TREE_CODE (t) == OVERLOAD
4810 || TREE_CODE (t) == BASELINK
4811 || TREE_CODE_CLASS (TREE_CODE (t)) == 'c')
4812 dependent_p = (type_dependent_expression_p (t)
4813 || value_dependent_expression_p (t));
4814 else if (t == error_mark_node)
4815 dependent_p = false;
4818 processing_template_decl = saved_processing_template_decl;
4823 /* Returns true if T depends on any template parameter with level LEVEL. */
4826 uses_template_parms_level (tree t, int level)
4828 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4831 static int tinst_depth;
4832 extern int max_tinst_depth;
4833 #ifdef GATHER_STATISTICS
4836 static int tinst_level_tick;
4837 static int last_template_error_tick;
4839 /* We're starting to instantiate D; record the template instantiation context
4840 for diagnostics and to restore it later. */
4843 push_tinst_level (tree d)
4847 if (tinst_depth >= max_tinst_depth)
4849 /* If the instantiation in question still has unbound template parms,
4850 we don't really care if we can't instantiate it, so just return.
4851 This happens with base instantiation for implicit `typename'. */
4852 if (uses_template_parms (d))
4855 last_template_error_tick = tinst_level_tick;
4856 error ("template instantiation depth exceeds maximum of %d (use -ftemplate-depth-NN to increase the maximum) instantiating `%D'",
4857 max_tinst_depth, d);
4859 print_instantiation_context ();
4864 new = build_expr_wfl (d, input_filename, input_line, 0);
4865 TREE_CHAIN (new) = current_tinst_level;
4866 current_tinst_level = new;
4869 #ifdef GATHER_STATISTICS
4870 if (tinst_depth > depth_reached)
4871 depth_reached = tinst_depth;
4878 /* We're done instantiating this template; return to the instantiation
4882 pop_tinst_level (void)
4884 tree old = current_tinst_level;
4886 /* Restore the filename and line number stashed away when we started
4887 this instantiation. */
4888 input_line = TINST_LINE (old);
4889 input_filename = TINST_FILE (old);
4890 extract_interface_info ();
4892 current_tinst_level = TREE_CHAIN (old);
4897 /* We're instantiating a deferred template; restore the template
4898 instantiation context in which the instantiation was requested, which
4899 is one step out from LEVEL. */
4902 reopen_tinst_level (tree level)
4907 for (t = level; t; t = TREE_CHAIN (t))
4910 current_tinst_level = level;
4914 /* Return the outermost template instantiation context, for use with
4915 -falt-external-templates. */
4918 tinst_for_decl (void)
4920 tree p = current_tinst_level;
4923 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
4928 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4929 vector of template arguments, as for tsubst.
4931 Returns an appropriate tsubst'd friend declaration. */
4934 tsubst_friend_function (tree decl, tree args)
4937 location_t saved_loc = input_location;
4939 input_location = DECL_SOURCE_LOCATION (decl);
4941 if (TREE_CODE (decl) == FUNCTION_DECL
4942 && DECL_TEMPLATE_INSTANTIATION (decl)
4943 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
4944 /* This was a friend declared with an explicit template
4945 argument list, e.g.:
4949 to indicate that f was a template instantiation, not a new
4950 function declaration. Now, we have to figure out what
4951 instantiation of what template. */
4953 tree template_id, arglist, fns;
4956 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
4958 /* Friend functions are looked up in the containing namespace scope.
4959 We must enter that scope, to avoid finding member functions of the
4960 current cless with same name. */
4961 push_nested_namespace (ns);
4962 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
4963 tf_error | tf_warning, NULL_TREE);
4964 pop_nested_namespace (ns);
4965 arglist = tsubst (DECL_TI_ARGS (decl), args,
4966 tf_error | tf_warning, NULL_TREE);
4967 template_id = lookup_template_function (fns, arglist);
4969 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
4970 tmpl = determine_specialization (template_id, new_friend,
4972 /*need_member_template=*/0);
4973 new_friend = instantiate_template (tmpl, new_args, tf_error);
4977 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
4979 /* The NEW_FRIEND will look like an instantiation, to the
4980 compiler, but is not an instantiation from the point of view of
4981 the language. For example, we might have had:
4983 template <class T> struct S {
4984 template <class U> friend void f(T, U);
4987 Then, in S<int>, template <class U> void f(int, U) is not an
4988 instantiation of anything. */
4989 if (new_friend == error_mark_node)
4990 return error_mark_node;
4992 DECL_USE_TEMPLATE (new_friend) = 0;
4993 if (TREE_CODE (decl) == TEMPLATE_DECL)
4995 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
4996 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
4997 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5000 /* The mangled name for the NEW_FRIEND is incorrect. The function
5001 is not a template instantiation and should not be mangled like
5002 one. Therefore, we forget the mangling here; we'll recompute it
5003 later if we need it. */
5004 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5006 SET_DECL_RTL (new_friend, NULL_RTX);
5007 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5010 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5013 tree new_friend_template_info;
5014 tree new_friend_result_template_info;
5016 int new_friend_is_defn;
5018 /* We must save some information from NEW_FRIEND before calling
5019 duplicate decls since that function will free NEW_FRIEND if
5021 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5022 new_friend_is_defn =
5023 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5024 (template_for_substitution (new_friend)))
5026 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5028 /* This declaration is a `primary' template. */
5029 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5031 new_friend_result_template_info
5032 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5035 new_friend_result_template_info = NULL_TREE;
5037 /* Inside pushdecl_namespace_level, we will push into the
5038 current namespace. However, the friend function should go
5039 into the namespace of the template. */
5040 ns = decl_namespace_context (new_friend);
5041 push_nested_namespace (ns);
5042 old_decl = pushdecl_namespace_level (new_friend);
5043 pop_nested_namespace (ns);
5045 if (old_decl != new_friend)
5047 /* This new friend declaration matched an existing
5048 declaration. For example, given:
5050 template <class T> void f(T);
5051 template <class U> class C {
5052 template <class T> friend void f(T) {}
5055 the friend declaration actually provides the definition
5056 of `f', once C has been instantiated for some type. So,
5057 old_decl will be the out-of-class template declaration,
5058 while new_friend is the in-class definition.
5060 But, if `f' was called before this point, the
5061 instantiation of `f' will have DECL_TI_ARGS corresponding
5062 to `T' but not to `U', references to which might appear
5063 in the definition of `f'. Previously, the most general
5064 template for an instantiation of `f' was the out-of-class
5065 version; now it is the in-class version. Therefore, we
5066 run through all specialization of `f', adding to their
5067 DECL_TI_ARGS appropriately. In particular, they need a
5068 new set of outer arguments, corresponding to the
5069 arguments for this class instantiation.
5071 The same situation can arise with something like this:
5074 template <class T> class C {
5078 when `C<int>' is instantiated. Now, `f(int)' is defined
5081 if (!new_friend_is_defn)
5082 /* On the other hand, if the in-class declaration does
5083 *not* provide a definition, then we don't want to alter
5084 existing definitions. We can just leave everything
5089 /* Overwrite whatever template info was there before, if
5090 any, with the new template information pertaining to
5092 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5094 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5095 reregister_specialization (new_friend,
5096 most_general_template (old_decl),
5101 tree new_friend_args;
5103 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5104 = new_friend_result_template_info;
5106 new_friend_args = TI_ARGS (new_friend_template_info);
5107 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5111 tree spec = TREE_VALUE (t);
5114 = add_outermost_template_args (new_friend_args,
5115 DECL_TI_ARGS (spec));
5118 /* Now, since specializations are always supposed to
5119 hang off of the most general template, we must move
5121 t = most_general_template (old_decl);
5124 DECL_TEMPLATE_SPECIALIZATIONS (t)
5125 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5126 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5127 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5132 /* The information from NEW_FRIEND has been merged into OLD_DECL
5133 by duplicate_decls. */
5134 new_friend = old_decl;
5137 else if (COMPLETE_TYPE_P (DECL_CONTEXT (new_friend)))
5139 /* Check to see that the declaration is really present, and,
5140 possibly obtain an improved declaration. */
5141 tree fn = check_classfn (DECL_CONTEXT (new_friend),
5149 input_location = saved_loc;
5153 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5154 template arguments, as for tsubst.
5156 Returns an appropriate tsubst'd friend type or error_mark_node on
5160 tsubst_friend_class (tree friend_tmpl, tree args)
5166 context = DECL_CONTEXT (friend_tmpl);
5170 if (TREE_CODE (context) == NAMESPACE_DECL)
5171 push_nested_namespace (context);
5173 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5176 /* First, we look for a class template. */
5177 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5179 /* But, if we don't find one, it might be because we're in a
5180 situation like this:
5188 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5189 for `S<int>', not the TEMPLATE_DECL. */
5190 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5192 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5193 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5196 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5198 /* The friend template has already been declared. Just
5199 check to see that the declarations match, and install any new
5200 default parameters. We must tsubst the default parameters,
5201 of course. We only need the innermost template parameters
5202 because that is all that redeclare_class_template will look
5204 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5205 > TMPL_ARGS_DEPTH (args))
5208 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5209 args, tf_error | tf_warning);
5210 redeclare_class_template (TREE_TYPE (tmpl), parms);
5213 friend_type = TREE_TYPE (tmpl);
5217 /* The friend template has not already been declared. In this
5218 case, the instantiation of the template class will cause the
5219 injection of this template into the global scope. */
5220 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5222 /* The new TMPL is not an instantiation of anything, so we
5223 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5224 the new type because that is supposed to be the corresponding
5225 template decl, i.e., TMPL. */
5226 DECL_USE_TEMPLATE (tmpl) = 0;
5227 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5228 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5229 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5230 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5232 /* Inject this template into the global scope. */
5233 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5238 if (TREE_CODE (context) == NAMESPACE_DECL)
5239 pop_nested_namespace (context);
5241 pop_nested_class ();
5247 /* Returns zero if TYPE cannot be completed later due to circularity.
5248 Otherwise returns one. */
5251 can_complete_type_without_circularity (tree type)
5253 if (type == NULL_TREE || type == error_mark_node)
5255 else if (COMPLETE_TYPE_P (type))
5257 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5258 return can_complete_type_without_circularity (TREE_TYPE (type));
5259 else if (CLASS_TYPE_P (type)
5260 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5267 instantiate_class_template (tree type)
5269 tree template, args, pattern, t, member;
5273 if (type == error_mark_node)
5274 return error_mark_node;
5276 if (TYPE_BEING_DEFINED (type)
5277 || COMPLETE_TYPE_P (type)
5278 || dependent_type_p (type))
5281 /* Figure out which template is being instantiated. */
5282 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5283 my_friendly_assert (TREE_CODE (template) == TEMPLATE_DECL, 279);
5285 /* Figure out which arguments are being used to do the
5287 args = CLASSTYPE_TI_ARGS (type);
5289 /* Determine what specialization of the original template to
5291 t = most_specialized_class (template, args);
5292 if (t == error_mark_node)
5294 const char *str = "candidates are:";
5295 error ("ambiguous class template instantiation for `%#T'", type);
5296 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5299 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5301 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5305 TYPE_BEING_DEFINED (type) = 1;
5306 return error_mark_node;
5310 pattern = TREE_TYPE (t);
5312 pattern = TREE_TYPE (template);
5314 /* If the template we're instantiating is incomplete, then clearly
5315 there's nothing we can do. */
5316 if (!COMPLETE_TYPE_P (pattern))
5319 /* If we've recursively instantiated too many templates, stop. */
5320 if (! push_tinst_level (type))
5323 /* Now we're really doing the instantiation. Mark the type as in
5324 the process of being defined. */
5325 TYPE_BEING_DEFINED (type) = 1;
5327 /* We may be in the middle of deferred access check. Disable
5329 push_deferring_access_checks (dk_no_deferred);
5331 push_to_top_level ();
5335 /* This TYPE is actually an instantiation of a partial
5336 specialization. We replace the innermost set of ARGS with
5337 the arguments appropriate for substitution. For example,
5340 template <class T> struct S {};
5341 template <class T> struct S<T*> {};
5343 and supposing that we are instantiating S<int*>, ARGS will
5344 present be {int*} but we need {int}. */
5346 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5349 /* If there were multiple levels in ARGS, replacing the
5350 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5351 want, so we make a copy first. */
5352 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5354 args = copy_node (args);
5355 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5361 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5363 /* Set the input location to the template definition. This is needed
5364 if tsubsting causes an error. */
5365 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (pattern));
5367 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5368 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5369 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5370 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5371 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5372 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5373 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5374 TYPE_HAS_ABSTRACT_ASSIGN_REF (type) = TYPE_HAS_ABSTRACT_ASSIGN_REF (pattern);
5375 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5376 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5377 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5378 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5379 TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
5380 = TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (pattern);
5381 TYPE_USES_MULTIPLE_INHERITANCE (type)
5382 = TYPE_USES_MULTIPLE_INHERITANCE (pattern);
5383 TYPE_USES_VIRTUAL_BASECLASSES (type)
5384 = TYPE_USES_VIRTUAL_BASECLASSES (pattern);
5385 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5386 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5387 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5388 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5389 if (ANON_AGGR_TYPE_P (pattern))
5390 SET_ANON_AGGR_TYPE_P (type);
5392 pbinfo = TYPE_BINFO (pattern);
5394 #ifdef ENABLE_CHECKING
5395 if (DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5396 && ! COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5397 && ! TYPE_BEING_DEFINED (TYPE_CONTEXT (type)))
5398 /* We should never instantiate a nested class before its enclosing
5399 class; we need to look up the nested class by name before we can
5400 instantiate it, and that lookup should instantiate the enclosing
5405 if (BINFO_BASETYPES (pbinfo))
5407 tree base_list = NULL_TREE;
5408 tree pbases = BINFO_BASETYPES (pbinfo);
5409 tree paccesses = BINFO_BASEACCESSES (pbinfo);
5410 tree context = TYPE_CONTEXT (type);
5414 /* We must enter the scope containing the type, as that is where
5415 the accessibility of types named in dependent bases are
5417 pop_p = push_scope (context ? context : global_namespace);
5419 /* Substitute into each of the bases to determine the actual
5421 for (i = 0; i < TREE_VEC_LENGTH (pbases); ++i)
5427 pbase = TREE_VEC_ELT (pbases, i);
5428 access = TREE_VEC_ELT (paccesses, i);
5430 /* Substitute to figure out the base class. */
5431 base = tsubst (BINFO_TYPE (pbase), args, tf_error, NULL_TREE);
5432 if (base == error_mark_node)
5435 base_list = tree_cons (access, base, base_list);
5436 TREE_VIA_VIRTUAL (base_list) = TREE_VIA_VIRTUAL (pbase);
5439 /* The list is now in reverse order; correct that. */
5440 base_list = nreverse (base_list);
5442 /* Now call xref_basetypes to set up all the base-class
5444 xref_basetypes (type, base_list);
5447 pop_scope (context ? context : global_namespace);
5450 /* Now that our base classes are set up, enter the scope of the
5451 class, so that name lookups into base classes, etc. will work
5452 correctly. This is precisely analogous to what we do in
5453 begin_class_definition when defining an ordinary non-template
5457 /* Now members are processed in the order of declaration. */
5458 for (member = CLASSTYPE_DECL_LIST (pattern);
5459 member; member = TREE_CHAIN (member))
5461 tree t = TREE_VALUE (member);
5463 if (TREE_PURPOSE (member))
5467 /* Build new CLASSTYPE_NESTED_UTDS. */
5470 tree name = TYPE_IDENTIFIER (tag);
5473 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5474 if (newtag == error_mark_node)
5477 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5479 if (TYPE_LANG_SPECIFIC (tag) && CLASSTYPE_IS_TEMPLATE (tag))
5480 /* Unfortunately, lookup_template_class sets
5481 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5482 instantiation (i.e., for the type of a member
5483 template class nested within a template class.)
5484 This behavior is required for
5485 maybe_process_partial_specialization to work
5486 correctly, but is not accurate in this case;
5487 the TAG is not an instantiation of anything.
5488 (The corresponding TEMPLATE_DECL is an
5489 instantiation, but the TYPE is not.) */
5490 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5492 /* Now, we call pushtag to put this NEWTAG into the scope of
5493 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5494 pushtag calling push_template_decl. We don't have to do
5495 this for enums because it will already have been done in
5498 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5499 pushtag (name, newtag, /*globalize=*/0);
5502 else if (TREE_CODE (t) == FUNCTION_DECL
5503 || DECL_FUNCTION_TEMPLATE_P (t))
5505 /* Build new TYPE_METHODS. */
5508 if (TREE_CODE (t) == TEMPLATE_DECL)
5509 ++processing_template_decl;
5510 r = tsubst (t, args, tf_error, NULL_TREE);
5511 if (TREE_CODE (t) == TEMPLATE_DECL)
5512 --processing_template_decl;
5513 set_current_access_from_decl (r);
5514 grok_special_member_properties (r);
5515 finish_member_declaration (r);
5519 /* Build new TYPE_FIELDS. */
5521 if (TREE_CODE (t) != CONST_DECL)
5525 /* The the file and line for this declaration, to
5526 assist in error message reporting. Since we
5527 called push_tinst_level above, we don't need to
5529 input_location = DECL_SOURCE_LOCATION (t);
5531 if (TREE_CODE (t) == TEMPLATE_DECL)
5532 ++processing_template_decl;
5533 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5534 if (TREE_CODE (t) == TEMPLATE_DECL)
5535 --processing_template_decl;
5536 if (TREE_CODE (r) == VAR_DECL)
5540 if (DECL_INITIALIZED_IN_CLASS_P (r))
5541 init = tsubst_expr (DECL_INITIAL (t), args,
5542 tf_error | tf_warning, NULL_TREE);
5546 finish_static_data_member_decl
5547 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5549 if (DECL_INITIALIZED_IN_CLASS_P (r))
5550 check_static_variable_definition (r, TREE_TYPE (r));
5552 else if (TREE_CODE (r) == FIELD_DECL)
5554 /* Determine whether R has a valid type and can be
5555 completed later. If R is invalid, then it is
5556 replaced by error_mark_node so that it will not be
5557 added to TYPE_FIELDS. */
5558 tree rtype = TREE_TYPE (r);
5559 if (can_complete_type_without_circularity (rtype))
5560 complete_type (rtype);
5562 if (!COMPLETE_TYPE_P (rtype))
5564 cxx_incomplete_type_error (r, rtype);
5565 r = error_mark_node;
5569 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5570 such a thing will already have been added to the field
5571 list by tsubst_enum in finish_member_declaration in the
5572 CLASSTYPE_NESTED_UTDS case above. */
5573 if (!(TREE_CODE (r) == TYPE_DECL
5574 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5575 && DECL_ARTIFICIAL (r)))
5577 set_current_access_from_decl (r);
5578 finish_member_declaration (r);
5585 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5587 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5589 tree friend_type = t;
5590 tree new_friend_type;
5592 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5593 new_friend_type = tsubst_friend_class (friend_type, args);
5594 else if (uses_template_parms (friend_type))
5595 new_friend_type = tsubst (friend_type, args,
5596 tf_error | tf_warning, NULL_TREE);
5597 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5598 new_friend_type = friend_type;
5601 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5603 /* The call to xref_tag_from_type does injection for friend
5605 push_nested_namespace (ns);
5607 xref_tag_from_type (friend_type, NULL_TREE, 1);
5608 pop_nested_namespace (ns);
5611 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5612 /* Trick make_friend_class into realizing that the friend
5613 we're adding is a template, not an ordinary class. It's
5614 important that we use make_friend_class since it will
5615 perform some error-checking and output cross-reference
5617 ++processing_template_decl;
5619 if (new_friend_type != error_mark_node)
5620 make_friend_class (type, new_friend_type,
5621 /*complain=*/false);
5623 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5624 --processing_template_decl;
5628 /* Build new DECL_FRIENDLIST. */
5631 if (TREE_CODE (t) == TEMPLATE_DECL)
5632 ++processing_template_decl;
5633 r = tsubst_friend_function (t, args);
5634 if (TREE_CODE (t) == TEMPLATE_DECL)
5635 --processing_template_decl;
5636 add_friend (type, r, /*complain=*/false);
5641 /* Set the file and line number information to whatever is given for
5642 the class itself. This puts error messages involving generated
5643 implicit functions at a predictable point, and the same point
5644 that would be used for non-template classes. */
5645 typedecl = TYPE_MAIN_DECL (type);
5646 input_location = DECL_SOURCE_LOCATION (typedecl);
5648 unreverse_member_declarations (type);
5649 finish_struct_1 (type);
5651 /* Clear this now so repo_template_used is happy. */
5652 TYPE_BEING_DEFINED (type) = 0;
5653 repo_template_used (type);
5655 /* Now that the class is complete, instantiate default arguments for
5656 any member functions. We don't do this earlier because the
5657 default arguments may reference members of the class. */
5658 if (!PRIMARY_TEMPLATE_P (template))
5659 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5660 if (TREE_CODE (t) == FUNCTION_DECL
5661 /* Implicitly generated member functions will not have template
5662 information; they are not instantiations, but instead are
5663 created "fresh" for each instantiation. */
5664 && DECL_TEMPLATE_INFO (t))
5665 tsubst_default_arguments (t);
5668 pop_from_top_level ();
5669 pop_deferring_access_checks ();
5672 if (TYPE_CONTAINS_VPTR_P (type))
5673 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5679 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5685 else if (TYPE_P (t))
5686 r = tsubst (t, args, complain, in_decl);
5689 r = tsubst_expr (t, args, complain, in_decl);
5691 if (!uses_template_parms (r))
5693 /* Sometimes, one of the args was an expression involving a
5694 template constant parameter, like N - 1. Now that we've
5695 tsubst'd, we might have something like 2 - 1. This will
5696 confuse lookup_template_class, so we do constant folding
5697 here. We have to unset processing_template_decl, to fool
5698 tsubst_copy_and_build() into building an actual tree. */
5700 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5701 as simple as it's going to get, and trying to reprocess
5702 the trees will break. Once tsubst_expr et al DTRT for
5703 non-dependent exprs, this code can go away, as the type
5704 will always be set. */
5707 int saved_processing_template_decl = processing_template_decl;
5708 processing_template_decl = 0;
5709 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5710 tf_error, /*in_decl=*/NULL_TREE,
5711 /*function_p=*/false);
5712 processing_template_decl = saved_processing_template_decl;
5720 /* Substitute ARGS into the vector or list of template arguments T. */
5723 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5725 int len = TREE_VEC_LENGTH (t);
5726 int need_new = 0, i;
5727 tree *elts = alloca (len * sizeof (tree));
5729 for (i = 0; i < len; i++)
5731 tree orig_arg = TREE_VEC_ELT (t, i);
5734 if (TREE_CODE (orig_arg) == TREE_VEC)
5735 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5737 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5739 if (new_arg == error_mark_node)
5740 return error_mark_node;
5743 if (new_arg != orig_arg)
5750 t = make_tree_vec (len);
5751 for (i = 0; i < len; i++)
5752 TREE_VEC_ELT (t, i) = elts[i];
5757 /* Return the result of substituting ARGS into the template parameters
5758 given by PARMS. If there are m levels of ARGS and m + n levels of
5759 PARMS, then the result will contain n levels of PARMS. For
5760 example, if PARMS is `template <class T> template <class U>
5761 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5762 result will be `template <int*, double, class V>'. */
5765 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5770 for (new_parms = &r;
5771 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5772 new_parms = &(TREE_CHAIN (*new_parms)),
5773 parms = TREE_CHAIN (parms))
5776 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5779 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5781 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5782 tree default_value = TREE_PURPOSE (tuple);
5783 tree parm_decl = TREE_VALUE (tuple);
5785 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5786 default_value = tsubst_template_arg (default_value, args,
5787 complain, NULL_TREE);
5789 tuple = build_tree_list (default_value, parm_decl);
5790 TREE_VEC_ELT (new_vec, i) = tuple;
5794 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
5795 - TMPL_ARGS_DEPTH (args)),
5796 new_vec, NULL_TREE);
5802 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5803 type T. If T is not an aggregate or enumeration type, it is
5804 handled as if by tsubst. IN_DECL is as for tsubst. If
5805 ENTERING_SCOPE is nonzero, T is the context for a template which
5806 we are presently tsubst'ing. Return the substituted value. */
5809 tsubst_aggr_type (tree t,
5811 tsubst_flags_t complain,
5818 switch (TREE_CODE (t))
5821 if (TYPE_PTRMEMFUNC_P (t))
5822 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
5824 /* Else fall through. */
5827 if (TYPE_TEMPLATE_INFO (t))
5833 /* First, determine the context for the type we are looking
5835 context = TYPE_CONTEXT (t);
5837 context = tsubst_aggr_type (context, args, complain,
5838 in_decl, /*entering_scope=*/1);
5840 /* Then, figure out what arguments are appropriate for the
5841 type we are trying to find. For example, given:
5843 template <class T> struct S;
5844 template <class T, class U> void f(T, U) { S<U> su; }
5846 and supposing that we are instantiating f<int, double>,
5847 then our ARGS will be {int, double}, but, when looking up
5848 S we only want {double}. */
5849 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
5851 if (argvec == error_mark_node)
5852 return error_mark_node;
5854 r = lookup_template_class (t, argvec, in_decl, context,
5855 entering_scope, complain);
5857 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
5860 /* This is not a template type, so there's nothing to do. */
5864 return tsubst (t, args, complain, in_decl);
5868 /* Substitute into the default argument ARG (a default argument for
5869 FN), which has the indicated TYPE. */
5872 tsubst_default_argument (tree fn, tree type, tree arg)
5874 /* This default argument came from a template. Instantiate the
5875 default argument here, not in tsubst. In the case of
5884 we must be careful to do name lookup in the scope of S<T>,
5885 rather than in the current class.
5887 ??? current_class_type affects a lot more than name lookup. This is
5888 very fragile. Fortunately, it will go away when we do 2-phase name
5889 binding properly. */
5891 /* FN is already the desired FUNCTION_DECL. */
5892 push_access_scope (fn);
5894 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
5895 tf_error | tf_warning, NULL_TREE);
5897 pop_access_scope (fn);
5899 /* Make sure the default argument is reasonable. */
5900 arg = check_default_argument (type, arg);
5905 /* Substitute into all the default arguments for FN. */
5908 tsubst_default_arguments (tree fn)
5913 tmpl_args = DECL_TI_ARGS (fn);
5915 /* If this function is not yet instantiated, we certainly don't need
5916 its default arguments. */
5917 if (uses_template_parms (tmpl_args))
5920 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
5922 arg = TREE_CHAIN (arg))
5923 if (TREE_PURPOSE (arg))
5924 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
5926 TREE_PURPOSE (arg));
5929 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
5930 (already computed) substitution of ARGS into TREE_TYPE (T), if
5931 appropriate. Return the result of the substitution. Issue error
5932 and warning messages under control of COMPLAIN. */
5935 tsubst_decl (tree t, tree args, tree type, tsubst_flags_t complain)
5937 location_t saved_loc;
5941 /* Set the filename and linenumber to improve error-reporting. */
5942 saved_loc = input_location;
5943 input_location = DECL_SOURCE_LOCATION (t);
5945 switch (TREE_CODE (t))
5949 /* We can get here when processing a member template function
5950 of a template class. */
5951 tree decl = DECL_TEMPLATE_RESULT (t);
5953 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
5955 if (!is_template_template_parm)
5957 /* We might already have an instance of this template.
5958 The ARGS are for the surrounding class type, so the
5959 full args contain the tsubst'd args for the context,
5960 plus the innermost args from the template decl. */
5961 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
5962 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
5963 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
5966 full_args = tsubst_template_args (tmpl_args, args,
5969 /* tsubst_template_args doesn't copy the vector if
5970 nothing changed. But, *something* should have
5972 my_friendly_assert (full_args != tmpl_args, 0);
5974 spec = retrieve_specialization (t, full_args);
5975 if (spec != NULL_TREE)
5982 /* Make a new template decl. It will be similar to the
5983 original, but will record the current template arguments.
5984 We also create a new function declaration, which is just
5985 like the old one, but points to this new template, rather
5986 than the old one. */
5988 my_friendly_assert (DECL_LANG_SPECIFIC (r) != 0, 0);
5989 TREE_CHAIN (r) = NULL_TREE;
5991 if (is_template_template_parm)
5993 tree new_decl = tsubst (decl, args, complain, in_decl);
5994 DECL_TEMPLATE_RESULT (r) = new_decl;
5995 TREE_TYPE (r) = TREE_TYPE (new_decl);
6000 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6002 /*entering_scope=*/1);
6003 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6005 if (TREE_CODE (decl) == TYPE_DECL)
6007 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6008 if (new_type == error_mark_node)
6009 return error_mark_node;
6011 TREE_TYPE (r) = new_type;
6012 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6013 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6014 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6018 tree new_decl = tsubst (decl, args, complain, in_decl);
6019 if (new_decl == error_mark_node)
6020 return error_mark_node;
6022 DECL_TEMPLATE_RESULT (r) = new_decl;
6023 DECL_TI_TEMPLATE (new_decl) = r;
6024 TREE_TYPE (r) = TREE_TYPE (new_decl);
6025 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6028 SET_DECL_IMPLICIT_INSTANTIATION (r);
6029 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6030 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6032 /* The template parameters for this new template are all the
6033 template parameters for the old template, except the
6034 outermost level of parameters. */
6035 DECL_TEMPLATE_PARMS (r)
6036 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6039 if (PRIMARY_TEMPLATE_P (t))
6040 DECL_PRIMARY_TEMPLATE (r) = r;
6042 if (TREE_CODE (decl) != TYPE_DECL)
6043 /* Record this non-type partial instantiation. */
6044 register_specialization (r, t,
6045 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6052 tree argvec = NULL_TREE;
6059 /* Nobody should be tsubst'ing into non-template functions. */
6060 my_friendly_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE, 0);
6062 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6067 /* If T is not dependent, just return it. We have to
6068 increment PROCESSING_TEMPLATE_DECL because
6069 value_dependent_expression_p assumes that nothing is
6070 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6071 ++processing_template_decl;
6072 dependent_p = value_dependent_expression_p (t);
6073 --processing_template_decl;
6077 /* Calculate the most general template of which R is a
6078 specialization, and the complete set of arguments used to
6080 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6081 argvec = tsubst_template_args (DECL_TI_ARGS
6082 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6083 args, complain, in_decl);
6085 /* Check to see if we already have this specialization. */
6086 spec = retrieve_specialization (gen_tmpl, argvec);
6094 /* We can see more levels of arguments than parameters if
6095 there was a specialization of a member template, like
6098 template <class T> struct S { template <class U> void f(); }
6099 template <> template <class U> void S<int>::f(U);
6101 Here, we'll be substituting into the specialization,
6102 because that's where we can find the code we actually
6103 want to generate, but we'll have enough arguments for
6104 the most general template.
6106 We also deal with the peculiar case:
6108 template <class T> struct S {
6109 template <class U> friend void f();
6111 template <class U> void f() {}
6113 template void f<double>();
6115 Here, the ARGS for the instantiation of will be {int,
6116 double}. But, we only need as many ARGS as there are
6117 levels of template parameters in CODE_PATTERN. We are
6118 careful not to get fooled into reducing the ARGS in
6121 template <class T> struct S { template <class U> void f(U); }
6122 template <class T> template <> void S<T>::f(int) {}
6124 which we can spot because the pattern will be a
6125 specialization in this case. */
6126 args_depth = TMPL_ARGS_DEPTH (args);
6128 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6129 if (args_depth > parms_depth
6130 && !DECL_TEMPLATE_SPECIALIZATION (t))
6131 args = get_innermost_template_args (args, parms_depth);
6135 /* This special case arises when we have something like this:
6137 template <class T> struct S {
6138 friend void f<int>(int, double);
6141 Here, the DECL_TI_TEMPLATE for the friend declaration
6142 will be an IDENTIFIER_NODE. We are being called from
6143 tsubst_friend_function, and we want only to create a
6144 new decl (R) with appropriate types so that we can call
6145 determine_specialization. */
6146 gen_tmpl = NULL_TREE;
6149 if (DECL_CLASS_SCOPE_P (t))
6151 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6155 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6156 complain, t, /*entering_scope=*/1);
6161 ctx = DECL_CONTEXT (t);
6163 type = tsubst (type, args, complain, in_decl);
6164 if (type == error_mark_node)
6165 return error_mark_node;
6167 /* We do NOT check for matching decls pushed separately at this
6168 point, as they may not represent instantiations of this
6169 template, and in any case are considered separate under the
6172 DECL_USE_TEMPLATE (r) = 0;
6173 TREE_TYPE (r) = type;
6174 /* Clear out the mangled name and RTL for the instantiation. */
6175 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6176 SET_DECL_RTL (r, NULL_RTX);
6177 DECL_INITIAL (r) = NULL_TREE;
6178 DECL_CONTEXT (r) = ctx;
6180 if (member && DECL_CONV_FN_P (r))
6181 /* Type-conversion operator. Reconstruct the name, in
6182 case it's the name of one of the template's parameters. */
6183 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6185 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6187 DECL_RESULT (r) = NULL_TREE;
6189 TREE_STATIC (r) = 0;
6190 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6191 DECL_EXTERNAL (r) = 1;
6192 DECL_INTERFACE_KNOWN (r) = 0;
6193 DECL_DEFER_OUTPUT (r) = 0;
6194 TREE_CHAIN (r) = NULL_TREE;
6195 DECL_PENDING_INLINE_INFO (r) = 0;
6196 DECL_PENDING_INLINE_P (r) = 0;
6197 DECL_SAVED_TREE (r) = NULL_TREE;
6199 if (DECL_CLONED_FUNCTION (r))
6201 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6203 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6204 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6207 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6208 this in the special friend case mentioned above where
6209 GEN_TMPL is NULL. */
6212 DECL_TEMPLATE_INFO (r)
6213 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6214 SET_DECL_IMPLICIT_INSTANTIATION (r);
6215 register_specialization (r, gen_tmpl, argvec);
6217 /* We're not supposed to instantiate default arguments
6218 until they are called, for a template. But, for a
6221 template <class T> void f ()
6222 { extern void g(int i = T()); }
6224 we should do the substitution when the template is
6225 instantiated. We handle the member function case in
6226 instantiate_class_template since the default arguments
6227 might refer to other members of the class. */
6229 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6230 && !uses_template_parms (argvec))
6231 tsubst_default_arguments (r);
6234 /* Copy the list of befriending classes. */
6235 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6237 friends = &TREE_CHAIN (*friends))
6239 *friends = copy_node (*friends);
6240 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6245 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6247 maybe_retrofit_in_chrg (r);
6248 if (DECL_CONSTRUCTOR_P (r))
6249 grok_ctor_properties (ctx, r);
6250 /* If this is an instantiation of a member template, clone it.
6251 If it isn't, that'll be handled by
6252 clone_constructors_and_destructors. */
6253 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6254 clone_function_decl (r, /*update_method_vec_p=*/0);
6256 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6257 grok_op_properties (r, DECL_FRIEND_P (r),
6258 (complain & tf_error) != 0);
6265 if (DECL_TEMPLATE_PARM_P (t))
6266 SET_DECL_TEMPLATE_PARM_P (r);
6268 TREE_TYPE (r) = type;
6269 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6271 if (DECL_INITIAL (r))
6273 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6274 DECL_INITIAL (r) = TREE_TYPE (r);
6276 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6280 DECL_CONTEXT (r) = NULL_TREE;
6282 if (!DECL_TEMPLATE_PARM_P (r))
6283 DECL_ARG_TYPE (r) = type_passed_as (type);
6285 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6286 complain, TREE_CHAIN (t));
6293 TREE_TYPE (r) = type;
6294 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6296 /* We don't have to set DECL_CONTEXT here; it is set by
6297 finish_member_declaration. */
6298 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6300 TREE_CHAIN (r) = NULL_TREE;
6301 if (VOID_TYPE_P (type))
6302 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6309 /* It is not a dependent using decl any more. */
6310 TREE_TYPE (r) = void_type_node;
6312 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6314 = tsubst_copy (DECL_NAME (t), args, complain, in_decl);
6315 TREE_CHAIN (r) = NULL_TREE;
6320 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6321 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6323 /* If this is the canonical decl, we don't have to mess with
6324 instantiations, and often we can't (for typename, template
6325 type parms and such). Note that TYPE_NAME is not correct for
6326 the above test if we've copied the type for a typedef. */
6327 r = TYPE_NAME (type);
6335 tree argvec = NULL_TREE;
6336 tree gen_tmpl = NULL_TREE;
6338 tree tmpl = NULL_TREE;
6342 /* Assume this is a non-local variable. */
6345 if (TYPE_P (CP_DECL_CONTEXT (t)))
6346 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6348 in_decl, /*entering_scope=*/1);
6349 else if (DECL_NAMESPACE_SCOPE_P (t))
6350 ctx = DECL_CONTEXT (t);
6353 /* Subsequent calls to pushdecl will fill this in. */
6358 /* Check to see if we already have this specialization. */
6361 tmpl = DECL_TI_TEMPLATE (t);
6362 gen_tmpl = most_general_template (tmpl);
6363 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6364 spec = retrieve_specialization (gen_tmpl, argvec);
6367 spec = retrieve_local_specialization (t);
6376 if (TREE_CODE (r) == VAR_DECL)
6378 type = complete_type (type);
6379 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6380 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6382 else if (DECL_SELF_REFERENCE_P (t))
6383 SET_DECL_SELF_REFERENCE_P (r);
6384 TREE_TYPE (r) = type;
6385 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6386 DECL_CONTEXT (r) = ctx;
6387 /* Clear out the mangled name and RTL for the instantiation. */
6388 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6389 SET_DECL_RTL (r, NULL_RTX);
6391 /* Don't try to expand the initializer until someone tries to use
6392 this variable; otherwise we run into circular dependencies. */
6393 DECL_INITIAL (r) = NULL_TREE;
6394 SET_DECL_RTL (r, NULL_RTX);
6395 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6397 /* Even if the original location is out of scope, the newly
6398 substituted one is not. */
6399 if (TREE_CODE (r) == VAR_DECL)
6401 DECL_DEAD_FOR_LOCAL (r) = 0;
6402 DECL_INITIALIZED_P (r) = 0;
6407 /* A static data member declaration is always marked
6408 external when it is declared in-class, even if an
6409 initializer is present. We mimic the non-template
6411 DECL_EXTERNAL (r) = 1;
6413 register_specialization (r, gen_tmpl, argvec);
6414 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6415 SET_DECL_IMPLICIT_INSTANTIATION (r);
6418 register_local_specialization (r, t);
6420 TREE_CHAIN (r) = NULL_TREE;
6421 if (TREE_CODE (r) == VAR_DECL && VOID_TYPE_P (type))
6422 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6423 /* Compute the size, alignment, etc. of R. */
6432 /* Restore the file and line information. */
6433 input_location = saved_loc;
6438 /* Substitute into the ARG_TYPES of a function type. */
6441 tsubst_arg_types (tree arg_types,
6443 tsubst_flags_t complain,
6446 tree remaining_arg_types;
6449 if (!arg_types || arg_types == void_list_node)
6452 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6453 args, complain, in_decl);
6454 if (remaining_arg_types == error_mark_node)
6455 return error_mark_node;
6457 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6458 if (type == error_mark_node)
6459 return error_mark_node;
6460 if (VOID_TYPE_P (type))
6462 if (complain & tf_error)
6464 error ("invalid parameter type `%T'", type);
6466 cp_error_at ("in declaration `%D'", in_decl);
6468 return error_mark_node;
6471 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6472 top-level qualifiers as required. */
6473 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6475 /* Note that we do not substitute into default arguments here. The
6476 standard mandates that they be instantiated only when needed,
6477 which is done in build_over_call. */
6478 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6479 remaining_arg_types);
6483 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6484 *not* handle the exception-specification for FNTYPE, because the
6485 initial substitution of explicitly provided template parameters
6486 during argument deduction forbids substitution into the
6487 exception-specification:
6491 All references in the function type of the function template to the
6492 corresponding template parameters are replaced by the specified tem-
6493 plate argument values. If a substitution in a template parameter or
6494 in the function type of the function template results in an invalid
6495 type, type deduction fails. [Note: The equivalent substitution in
6496 exception specifications is done only when the function is instanti-
6497 ated, at which point a program is ill-formed if the substitution
6498 results in an invalid type.] */
6501 tsubst_function_type (tree t,
6503 tsubst_flags_t complain,
6510 /* The TYPE_CONTEXT is not used for function/method types. */
6511 my_friendly_assert (TYPE_CONTEXT (t) == NULL_TREE, 0);
6513 /* Substitute the return type. */
6514 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6515 if (return_type == error_mark_node)
6516 return error_mark_node;
6518 /* Substitute the argument types. */
6519 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6521 if (arg_types == error_mark_node)
6522 return error_mark_node;
6524 /* Construct a new type node and return it. */
6525 if (TREE_CODE (t) == FUNCTION_TYPE)
6526 fntype = build_function_type (return_type, arg_types);
6529 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6530 if (! IS_AGGR_TYPE (r))
6534 Type deduction may fail for any of the following
6537 -- Attempting to create "pointer to member of T" when T
6538 is not a class type. */
6539 if (complain & tf_error)
6540 error ("creating pointer to member function of non-class type `%T'",
6542 return error_mark_node;
6545 fntype = build_method_type_directly (r, return_type,
6546 TREE_CHAIN (arg_types));
6548 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6549 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6554 /* Substitute into the PARMS of a call-declarator. */
6557 tsubst_call_declarator_parms (tree parms,
6559 tsubst_flags_t complain,
6566 if (!parms || parms == void_list_node)
6569 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6570 args, complain, in_decl);
6572 /* Figure out the type of this parameter. */
6573 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6575 /* Figure out the default argument as well. Note that we use
6576 tsubst_expr since the default argument is really an expression. */
6577 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6579 /* Chain this parameter on to the front of those we have already
6580 processed. We don't use hash_tree_cons because that function
6581 doesn't check TREE_PARMLIST. */
6582 new_parms = tree_cons (defarg, type, new_parms);
6584 /* And note that these are parameters. */
6585 TREE_PARMLIST (new_parms) = 1;
6590 /* Take the tree structure T and replace template parameters used
6591 therein with the argument vector ARGS. IN_DECL is an associated
6592 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6593 Issue error and warning messages under control of COMPLAIN. Note
6594 that we must be relatively non-tolerant of extensions here, in
6595 order to preserve conformance; if we allow substitutions that
6596 should not be allowed, we may allow argument deductions that should
6597 not succeed, and therefore report ambiguous overload situations
6598 where there are none. In theory, we could allow the substitution,
6599 but indicate that it should have failed, and allow our caller to
6600 make sure that the right thing happens, but we don't try to do this
6603 This function is used for dealing with types, decls and the like;
6604 for expressions, use tsubst_expr or tsubst_copy. */
6607 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6611 if (t == NULL_TREE || t == error_mark_node
6612 || t == integer_type_node
6613 || t == void_type_node
6614 || t == char_type_node
6615 || TREE_CODE (t) == NAMESPACE_DECL)
6618 if (TREE_CODE (t) == IDENTIFIER_NODE)
6619 type = IDENTIFIER_TYPE_VALUE (t);
6621 type = TREE_TYPE (t);
6623 my_friendly_assert (type != unknown_type_node, 20030716);
6625 if (type && TREE_CODE (t) != FUNCTION_DECL
6626 && TREE_CODE (t) != TYPENAME_TYPE
6627 && TREE_CODE (t) != TEMPLATE_DECL
6628 && TREE_CODE (t) != IDENTIFIER_NODE
6629 && TREE_CODE (t) != FUNCTION_TYPE
6630 && TREE_CODE (t) != METHOD_TYPE)
6631 type = tsubst (type, args, complain, in_decl);
6632 if (type == error_mark_node)
6633 return error_mark_node;
6636 return tsubst_decl (t, args, type, complain);
6638 switch (TREE_CODE (t))
6643 return tsubst_aggr_type (t, args, complain, in_decl,
6644 /*entering_scope=*/0);
6647 case IDENTIFIER_NODE:
6659 if (t == integer_type_node)
6662 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6663 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6667 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6669 /* The array dimension behaves like a non-type template arg,
6670 in that we want to fold it as much as possible. */
6671 max = tsubst_template_arg (omax, args, complain, in_decl);
6672 if (!processing_template_decl)
6673 max = decl_constant_value (max);
6675 if (integer_zerop (omax))
6677 /* Still allow an explicit array of size zero. */
6679 pedwarn ("creating array with size zero");
6681 else if (integer_zerop (max)
6682 || (TREE_CODE (max) == INTEGER_CST
6683 && INT_CST_LT (max, integer_zero_node)))
6687 Type deduction may fail for any of the following
6690 Attempting to create an array with a size that is
6691 zero or negative. */
6692 if (complain & tf_error)
6693 error ("creating array with size zero (`%E')", max);
6695 return error_mark_node;
6698 return compute_array_index_type (NULL_TREE, max);
6701 case TEMPLATE_TYPE_PARM:
6702 case TEMPLATE_TEMPLATE_PARM:
6703 case BOUND_TEMPLATE_TEMPLATE_PARM:
6704 case TEMPLATE_PARM_INDEX:
6712 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6713 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6714 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6716 idx = TEMPLATE_TYPE_IDX (t);
6717 level = TEMPLATE_TYPE_LEVEL (t);
6721 idx = TEMPLATE_PARM_IDX (t);
6722 level = TEMPLATE_PARM_LEVEL (t);
6725 if (TREE_VEC_LENGTH (args) > 0)
6727 tree arg = NULL_TREE;
6729 levels = TMPL_ARGS_DEPTH (args);
6730 if (level <= levels)
6731 arg = TMPL_ARG (args, level, idx);
6733 if (arg == error_mark_node)
6734 return error_mark_node;
6735 else if (arg != NULL_TREE)
6737 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6739 my_friendly_assert (TYPE_P (arg), 0);
6740 return cp_build_qualified_type_real
6741 (arg, cp_type_quals (arg) | cp_type_quals (t),
6742 complain | tf_ignore_bad_quals);
6744 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6746 /* We are processing a type constructed from
6747 a template template parameter. */
6748 tree argvec = tsubst (TYPE_TI_ARGS (t),
6749 args, complain, in_decl);
6750 if (argvec == error_mark_node)
6751 return error_mark_node;
6753 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6754 we are resolving nested-types in the signature of
6755 a member function templates.
6756 Otherwise ARG is a TEMPLATE_DECL and is the real
6757 template to be instantiated. */
6758 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
6759 arg = TYPE_NAME (arg);
6761 r = lookup_template_class (arg,
6764 /*entering_scope=*/0,
6766 return cp_build_qualified_type_real
6767 (r, TYPE_QUALS (t), complain);
6770 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
6778 /* This can happen during the attempted tsubst'ing in
6779 unify. This means that we don't yet have any information
6780 about the template parameter in question. */
6783 /* If we get here, we must have been looking at a parm for a
6784 more deeply nested template. Make a new version of this
6785 template parameter, but with a lower level. */
6786 switch (TREE_CODE (t))
6788 case TEMPLATE_TYPE_PARM:
6789 case TEMPLATE_TEMPLATE_PARM:
6790 case BOUND_TEMPLATE_TEMPLATE_PARM:
6791 if (cp_type_quals (t))
6793 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
6794 r = cp_build_qualified_type_real
6795 (r, cp_type_quals (t),
6796 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6797 ? tf_ignore_bad_quals : 0));
6802 TEMPLATE_TYPE_PARM_INDEX (r)
6803 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
6805 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
6806 TYPE_MAIN_VARIANT (r) = r;
6807 TYPE_POINTER_TO (r) = NULL_TREE;
6808 TYPE_REFERENCE_TO (r) = NULL_TREE;
6810 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6812 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
6814 if (argvec == error_mark_node)
6815 return error_mark_node;
6817 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
6818 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
6823 case TEMPLATE_PARM_INDEX:
6824 r = reduce_template_parm_level (t, type, levels);
6836 tree purpose, value, chain, result;
6838 if (t == void_list_node)
6841 purpose = TREE_PURPOSE (t);
6844 purpose = tsubst (purpose, args, complain, in_decl);
6845 if (purpose == error_mark_node)
6846 return error_mark_node;
6848 value = TREE_VALUE (t);
6851 value = tsubst (value, args, complain, in_decl);
6852 if (value == error_mark_node)
6853 return error_mark_node;
6855 chain = TREE_CHAIN (t);
6856 if (chain && chain != void_type_node)
6858 chain = tsubst (chain, args, complain, in_decl);
6859 if (chain == error_mark_node)
6860 return error_mark_node;
6862 if (purpose == TREE_PURPOSE (t)
6863 && value == TREE_VALUE (t)
6864 && chain == TREE_CHAIN (t))
6866 if (TREE_PARMLIST (t))
6868 result = tree_cons (purpose, value, chain);
6869 TREE_PARMLIST (result) = 1;
6872 result = hash_tree_cons (purpose, value, chain);
6876 if (type != NULL_TREE)
6878 /* A binfo node. We always need to make a copy, of the node
6879 itself and of its BINFO_BASETYPES. */
6883 /* Make sure type isn't a typedef copy. */
6884 type = BINFO_TYPE (TYPE_BINFO (type));
6886 TREE_TYPE (t) = complete_type (type);
6887 if (IS_AGGR_TYPE (type))
6889 BINFO_VTABLE (t) = TYPE_BINFO_VTABLE (type);
6890 BINFO_VIRTUALS (t) = TYPE_BINFO_VIRTUALS (type);
6891 if (TYPE_BINFO_BASETYPES (type) != NULL_TREE)
6892 BINFO_BASETYPES (t) = copy_node (TYPE_BINFO_BASETYPES (type));
6897 /* Otherwise, a vector of template arguments. */
6898 return tsubst_template_args (t, args, complain, in_decl);
6901 case REFERENCE_TYPE:
6903 enum tree_code code;
6905 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
6908 code = TREE_CODE (t);
6913 Type deduction may fail for any of the following
6916 -- Attempting to create a pointer to reference type.
6917 -- Attempting to create a reference to a reference type or
6918 a reference to void. */
6919 if (TREE_CODE (type) == REFERENCE_TYPE
6920 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
6922 static location_t last_loc;
6924 /* We keep track of the last time we issued this error
6925 message to avoid spewing a ton of messages during a
6926 single bad template instantiation. */
6927 if (complain & tf_error
6928 && (last_loc.line != input_line
6929 || last_loc.file != input_filename))
6931 if (TREE_CODE (type) == VOID_TYPE)
6932 error ("forming reference to void");
6934 error ("forming %s to reference type `%T'",
6935 (code == POINTER_TYPE) ? "pointer" : "reference",
6937 last_loc = input_location;
6940 return error_mark_node;
6942 else if (code == POINTER_TYPE)
6944 r = build_pointer_type (type);
6945 if (TREE_CODE (type) == METHOD_TYPE)
6946 r = build_ptrmemfunc_type (r);
6949 r = build_reference_type (type);
6950 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6952 if (r != error_mark_node)
6953 /* Will this ever be needed for TYPE_..._TO values? */
6960 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
6961 if (r == error_mark_node || !IS_AGGR_TYPE (r))
6965 Type deduction may fail for any of the following
6968 -- Attempting to create "pointer to member of T" when T
6969 is not a class type. */
6970 if (complain & tf_error)
6971 error ("creating pointer to member of non-class type `%T'", r);
6972 return error_mark_node;
6974 if (TREE_CODE (type) == REFERENCE_TYPE)
6976 if (complain & tf_error)
6977 error ("creating pointer to member reference type `%T'", type);
6979 return error_mark_node;
6981 my_friendly_assert (TREE_CODE (type) != METHOD_TYPE, 20011231);
6982 if (TREE_CODE (type) == FUNCTION_TYPE)
6984 /* This is really a method type. The cv qualifiers of the
6985 this pointer should _not_ be determined by the cv
6986 qualifiers of the class type. They should be held
6987 somewhere in the FUNCTION_TYPE, but we don't do that at
6988 the moment. Consider
6989 typedef void (Func) () const;
6991 template <typename T1> void Foo (Func T1::*);
6996 method_type = build_method_type_directly (TYPE_MAIN_VARIANT (r),
6998 TYPE_ARG_TYPES (type));
6999 return build_ptrmemfunc_type (build_pointer_type (method_type));
7002 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7012 fntype = tsubst_function_type (t, args, complain, in_decl);
7013 if (fntype == error_mark_node)
7014 return error_mark_node;
7016 /* Substitute the exception specification. */
7017 raises = TYPE_RAISES_EXCEPTIONS (t);
7020 tree list = NULL_TREE;
7022 if (! TREE_VALUE (raises))
7025 for (; raises != NULL_TREE; raises = TREE_CHAIN (raises))
7027 tree spec = TREE_VALUE (raises);
7029 spec = tsubst (spec, args, complain, in_decl);
7030 if (spec == error_mark_node)
7032 list = add_exception_specifier (list, spec, complain);
7034 fntype = build_exception_variant (fntype, list);
7040 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7041 if (domain == error_mark_node)
7042 return error_mark_node;
7044 /* As an optimization, we avoid regenerating the array type if
7045 it will obviously be the same as T. */
7046 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7049 /* These checks should match the ones in grokdeclarator.
7053 The deduction may fail for any of the following reasons:
7055 -- Attempting to create an array with an element type that
7056 is void, a function type, or a reference type, or [DR337]
7057 an abstract class type. */
7058 if (TREE_CODE (type) == VOID_TYPE
7059 || TREE_CODE (type) == FUNCTION_TYPE
7060 || TREE_CODE (type) == REFERENCE_TYPE)
7062 if (complain & tf_error)
7063 error ("creating array of `%T'", type);
7064 return error_mark_node;
7066 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7068 if (complain & tf_error)
7069 error ("creating array of `%T', which is an abstract class type",
7071 return error_mark_node;
7074 r = build_cplus_array_type (type, domain);
7081 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7082 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7084 if (e1 == error_mark_node || e2 == error_mark_node)
7085 return error_mark_node;
7087 return fold (build (TREE_CODE (t), TREE_TYPE (t), e1, e2));
7093 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7094 if (e == error_mark_node)
7095 return error_mark_node;
7097 return fold (build (TREE_CODE (t), TREE_TYPE (t), e));
7102 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7103 in_decl, /*entering_scope=*/1);
7104 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7107 if (ctx == error_mark_node || f == error_mark_node)
7108 return error_mark_node;
7110 if (!IS_AGGR_TYPE (ctx))
7112 if (complain & tf_error)
7113 error ("`%T' is not a class, struct, or union type",
7115 return error_mark_node;
7117 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7119 /* Normally, make_typename_type does not require that the CTX
7120 have complete type in order to allow things like:
7122 template <class T> struct S { typename S<T>::X Y; };
7124 But, such constructs have already been resolved by this
7125 point, so here CTX really should have complete type, unless
7126 it's a partial instantiation. */
7127 ctx = complete_type (ctx);
7128 if (!COMPLETE_TYPE_P (ctx))
7130 if (complain & tf_error)
7131 cxx_incomplete_type_error (NULL_TREE, ctx);
7132 return error_mark_node;
7136 f = make_typename_type (ctx, f,
7137 (complain & tf_error) | tf_keep_type_decl);
7138 if (f == error_mark_node)
7140 if (TREE_CODE (f) == TYPE_DECL)
7142 complain |= tf_ignore_bad_quals;
7146 return cp_build_qualified_type_real
7147 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7150 case UNBOUND_CLASS_TEMPLATE:
7152 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7153 in_decl, /*entering_scope=*/1);
7154 tree name = TYPE_IDENTIFIER (t);
7156 if (ctx == error_mark_node || name == error_mark_node)
7157 return error_mark_node;
7159 return make_unbound_class_template (ctx, name, complain);
7164 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7165 if (e == error_mark_node)
7166 return error_mark_node;
7167 return make_pointer_declarator (type, e);
7172 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7173 if (e == error_mark_node)
7174 return error_mark_node;
7175 return make_reference_declarator (type, e);
7180 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7181 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7182 if (e1 == error_mark_node || e2 == error_mark_node)
7183 return error_mark_node;
7185 return build_nt (ARRAY_REF, e1, e2);
7190 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7191 tree e2 = (tsubst_call_declarator_parms
7192 (CALL_DECLARATOR_PARMS (t), args, complain, in_decl));
7193 tree e3 = tsubst (CALL_DECLARATOR_EXCEPTION_SPEC (t), args,
7196 if (e1 == error_mark_node || e2 == error_mark_node
7197 || e3 == error_mark_node)
7198 return error_mark_node;
7200 return make_call_declarator (e1, e2, CALL_DECLARATOR_QUALS (t), e3);
7205 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7206 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7207 if (e1 == error_mark_node || e2 == error_mark_node)
7208 return error_mark_node;
7210 return build_nt (TREE_CODE (t), e1, e2);
7217 type = finish_typeof (tsubst_expr (TYPE_FIELDS (t), args, complain,
7219 return cp_build_qualified_type_real (type,
7221 | cp_type_quals (type),
7226 sorry ("use of `%s' in template",
7227 tree_code_name [(int) TREE_CODE (t)]);
7228 return error_mark_node;
7232 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7233 type of the expression on the left-hand side of the "." or "->"
7237 tsubst_baselink (tree baselink, tree object_type,
7238 tree args, tsubst_flags_t complain, tree in_decl)
7241 tree qualifying_scope;
7243 tree template_args = 0;
7244 bool template_id_p = false;
7246 /* A baselink indicates a function from a base class. The
7247 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7248 non-dependent types; otherwise, the lookup could not have
7249 succeeded. However, they may indicate bases of the template
7250 class, rather than the instantiated class.
7252 In addition, lookups that were not ambiguous before may be
7253 ambiguous now. Therefore, we perform the lookup again. */
7254 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7255 fns = BASELINK_FUNCTIONS (baselink);
7256 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7258 template_id_p = true;
7259 template_args = TREE_OPERAND (fns, 1);
7260 fns = TREE_OPERAND (fns, 0);
7262 template_args = tsubst_template_args (template_args, args,
7265 name = DECL_NAME (get_first_fn (fns));
7266 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7267 if (BASELINK_P (baselink) && template_id_p)
7268 BASELINK_FUNCTIONS (baselink)
7269 = build_nt (TEMPLATE_ID_EXPR,
7270 BASELINK_FUNCTIONS (baselink),
7273 object_type = current_class_type;
7274 return adjust_result_of_qualified_name_lookup (baselink,
7279 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7280 true if the qualified-id will be a postfix-expression in-and-of
7281 itself; false if more of the postfix-expression follows the
7282 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7286 tsubst_qualified_id (tree qualified_id, tree args,
7287 tsubst_flags_t complain, tree in_decl,
7288 bool done, bool address_p)
7296 my_friendly_assert (TREE_CODE (qualified_id) == SCOPE_REF, 20030706);
7298 /* Figure out what name to look up. */
7299 name = TREE_OPERAND (qualified_id, 1);
7300 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7303 template_args = TREE_OPERAND (name, 1);
7305 template_args = tsubst_template_args (template_args, args,
7307 name = TREE_OPERAND (name, 0);
7311 is_template = false;
7312 template_args = NULL_TREE;
7315 /* Substitute into the qualifying scope. When there are no ARGS, we
7316 are just trying to simplify a non-dependent expression. In that
7317 case the qualifying scope may be dependent, and, in any case,
7318 substituting will not help. */
7319 scope = TREE_OPERAND (qualified_id, 0);
7322 scope = tsubst (scope, args, complain, in_decl);
7323 expr = tsubst_copy (name, args, complain, in_decl);
7328 if (dependent_type_p (scope))
7329 return build_nt (SCOPE_REF, scope, expr);
7331 if (!BASELINK_P (name) && !DECL_P (expr))
7333 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7334 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7335 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7337 if (complain & tf_error)
7339 error ("dependent-name `%E' is parsed as a non-type, but "
7340 "instantiation yields a type", qualified_id);
7341 inform ("say `typename %E' if a type is meant", qualified_id);
7343 return error_mark_node;
7348 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7351 /* Remember that there was a reference to this entity. */
7356 expr = lookup_template_function (expr, template_args);
7358 if (expr == error_mark_node && complain & tf_error)
7359 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1));
7360 else if (TYPE_P (scope))
7362 expr = (adjust_result_of_qualified_name_lookup
7363 (expr, scope, current_class_type));
7364 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7370 /* Like tsubst, but deals with expressions. This function just replaces
7371 template parms; to finish processing the resultant expression, use
7375 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7377 enum tree_code code;
7380 if (t == NULL_TREE || t == error_mark_node)
7383 code = TREE_CODE (t);
7388 r = retrieve_local_specialization (t);
7389 my_friendly_assert (r != NULL, 20020903);
7398 if (DECL_TEMPLATE_PARM_P (t))
7399 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7400 /* There is no need to substitute into namespace-scope
7402 if (DECL_NAMESPACE_SCOPE_P (t))
7405 /* Unfortunately, we cannot just call lookup_name here.
7408 template <int I> int f() {
7410 struct S { void g() { E e = a; } };
7413 When we instantiate f<7>::S::g(), say, lookup_name is not
7414 clever enough to find f<7>::a. */
7416 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7417 /*entering_scope=*/0);
7419 for (v = TYPE_VALUES (enum_type);
7422 if (TREE_PURPOSE (v) == DECL_NAME (t))
7423 return TREE_VALUE (v);
7425 /* We didn't find the name. That should never happen; if
7426 name-lookup found it during preliminary parsing, we
7427 should find it again here during instantiation. */
7433 if (DECL_CONTEXT (t))
7437 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7438 /*entering_scope=*/1);
7439 if (ctx != DECL_CONTEXT (t))
7440 return lookup_field (ctx, DECL_NAME (t), 0, false);
7446 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7447 || local_variable_p (t))
7448 t = tsubst (t, args, complain, in_decl);
7453 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7456 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7457 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7458 args, complain, in_decl);
7459 else if (is_member_template (t))
7460 return tsubst (t, args, complain, in_decl);
7461 else if (DECL_CLASS_SCOPE_P (t)
7462 && uses_template_parms (DECL_CONTEXT (t)))
7464 /* Template template argument like the following example need
7467 template <template <class> class TT> struct C {};
7468 template <class T> struct D {
7469 template <class U> struct E {};
7474 We are processing the template argument `E' in #1 for
7475 the template instantiation #2. Originally, `E' is a
7476 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7477 have to substitute this with one having context `D<int>'. */
7479 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7480 return lookup_field (context, DECL_NAME(t), 0, false);
7483 /* Ordinary template template argument. */
7487 case REINTERPRET_CAST_EXPR:
7488 case CONST_CAST_EXPR:
7489 case STATIC_CAST_EXPR:
7490 case DYNAMIC_CAST_EXPR:
7493 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7494 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7498 case TRUTH_NOT_EXPR:
7501 case CONVERT_EXPR: /* Unary + */
7510 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7511 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7518 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7519 name = TREE_OPERAND (t, 1);
7520 if (TREE_CODE (name) == BIT_NOT_EXPR)
7522 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7524 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7526 else if (TREE_CODE (name) == SCOPE_REF
7527 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7529 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7531 name = TREE_OPERAND (name, 1);
7532 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7534 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7535 name = build_nt (SCOPE_REF, base, name);
7537 else if (TREE_CODE (name) == BASELINK)
7538 name = tsubst_baselink (name,
7539 non_reference (TREE_TYPE (object)),
7543 name = tsubst_copy (name, args, complain, in_decl);
7544 return build_nt (COMPONENT_REF, object, name);
7550 case TRUNC_DIV_EXPR:
7552 case FLOOR_DIV_EXPR:
7553 case ROUND_DIV_EXPR:
7554 case EXACT_DIV_EXPR:
7558 case TRUNC_MOD_EXPR:
7559 case FLOOR_MOD_EXPR:
7560 case TRUTH_ANDIF_EXPR:
7561 case TRUTH_ORIF_EXPR:
7562 case TRUTH_AND_EXPR:
7581 case PREDECREMENT_EXPR:
7582 case PREINCREMENT_EXPR:
7583 case POSTDECREMENT_EXPR:
7584 case POSTINCREMENT_EXPR:
7586 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7587 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7590 return build_nt (code,
7591 tsubst_copy (TREE_OPERAND (t, 0), args,
7593 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7598 /* This processing should really occur in tsubst_expr. However,
7599 tsubst_expr does not recurse into expressions, since it
7600 assumes that there aren't any statements inside them. So, we
7601 need to expand the STMT_EXPR here. */
7602 if (!processing_template_decl)
7604 tree stmt_expr = begin_stmt_expr ();
7606 tsubst_expr (STMT_EXPR_STMT (t), args,
7607 complain | tf_stmt_expr_cmpd, in_decl);
7608 return finish_stmt_expr (stmt_expr, false);
7615 case PSEUDO_DTOR_EXPR:
7618 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7619 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7620 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7627 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7628 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7629 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7630 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7637 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7638 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7639 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7640 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7644 case TEMPLATE_ID_EXPR:
7646 /* Substituted template arguments */
7647 tree fn = TREE_OPERAND (t, 0);
7648 tree targs = TREE_OPERAND (t, 1);
7650 fn = tsubst_copy (fn, args, complain, in_decl);
7652 targs = tsubst_template_args (targs, args, complain, in_decl);
7654 return lookup_template_function (fn, targs);
7659 tree purpose, value, chain;
7661 if (t == void_list_node)
7664 purpose = TREE_PURPOSE (t);
7666 purpose = tsubst_copy (purpose, args, complain, in_decl);
7667 value = TREE_VALUE (t);
7669 value = tsubst_copy (value, args, complain, in_decl);
7670 chain = TREE_CHAIN (t);
7671 if (chain && chain != void_type_node)
7672 chain = tsubst_copy (chain, args, complain, in_decl);
7673 if (purpose == TREE_PURPOSE (t)
7674 && value == TREE_VALUE (t)
7675 && chain == TREE_CHAIN (t))
7677 return tree_cons (purpose, value, chain);
7684 case TEMPLATE_TYPE_PARM:
7685 case TEMPLATE_TEMPLATE_PARM:
7686 case BOUND_TEMPLATE_TEMPLATE_PARM:
7687 case TEMPLATE_PARM_INDEX:
7689 case REFERENCE_TYPE:
7695 case UNBOUND_CLASS_TEMPLATE:
7698 return tsubst (t, args, complain, in_decl);
7700 case IDENTIFIER_NODE:
7701 if (IDENTIFIER_TYPENAME_P (t))
7703 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7704 return mangle_conv_op_name_for_type (new_type);
7711 r = build_constructor
7712 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7713 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7714 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7719 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7721 tsubst (TREE_TYPE (t), args, complain, in_decl));
7728 /* Like tsubst_copy for expressions, etc. but also does semantic
7732 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7735 tsubst_flags_t stmt_expr
7736 = complain & (tf_stmt_expr_cmpd | tf_stmt_expr_body);
7738 complain ^= stmt_expr;
7739 if (t == NULL_TREE || t == error_mark_node)
7742 if (!STATEMENT_CODE_P (TREE_CODE (t)))
7743 return tsubst_copy_and_build (t, args, complain, in_decl,
7744 /*function_p=*/false);
7746 switch (TREE_CODE (t))
7748 case CTOR_INITIALIZER:
7750 finish_mem_initializers (tsubst_initializer_list
7751 (TREE_OPERAND (t, 0), args));
7756 finish_return_stmt (tsubst_expr (RETURN_STMT_EXPR (t),
7757 args, complain, in_decl));
7766 r = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
7767 if (stmt_expr & tf_stmt_expr_body && !TREE_CHAIN (t))
7768 finish_stmt_expr_expr (r);
7770 finish_expr_stmt (r);
7776 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
7777 args, complain, in_decl));
7786 decl = DECL_STMT_DECL (t);
7787 if (TREE_CODE (decl) == LABEL_DECL)
7788 finish_label_decl (DECL_NAME (decl));
7789 else if (TREE_CODE (decl) == USING_DECL)
7791 tree scope = DECL_INITIAL (decl);
7792 tree name = DECL_NAME (decl);
7795 scope = tsubst_expr (scope, args, complain, in_decl);
7796 decl = lookup_qualified_name (scope, name,
7797 /*is_type_p=*/false,
7798 /*complain=*/false);
7799 if (decl == error_mark_node)
7800 qualified_name_lookup_error (scope, name);
7802 do_local_using_decl (decl, scope, name);
7806 init = DECL_INITIAL (decl);
7807 decl = tsubst (decl, args, complain, in_decl);
7808 if (decl != error_mark_node)
7811 DECL_INITIAL (decl) = error_mark_node;
7812 /* By marking the declaration as instantiated, we avoid
7813 trying to instantiate it. Since instantiate_decl can't
7814 handle local variables, and since we've already done
7815 all that needs to be done, that's the right thing to
7817 if (TREE_CODE (decl) == VAR_DECL)
7818 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7819 if (TREE_CODE (decl) == VAR_DECL
7820 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
7821 /* Anonymous aggregates are a special case. */
7822 finish_anon_union (decl);
7825 maybe_push_decl (decl);
7826 if (TREE_CODE (decl) == VAR_DECL
7827 && DECL_PRETTY_FUNCTION_P (decl))
7829 /* For __PRETTY_FUNCTION__ we have to adjust the
7831 const char *const name
7832 = cxx_printable_name (current_function_decl, 2);
7833 init = cp_fname_init (name, &TREE_TYPE (decl));
7836 init = tsubst_expr (init, args, complain, in_decl);
7837 cp_finish_decl (decl, init, NULL_TREE, 0);
7842 /* A DECL_STMT can also be used as an expression, in the condition
7843 clause of an if/for/while construct. If we aren't followed by
7844 another statement, return our decl. */
7845 if (TREE_CHAIN (t) == NULL_TREE)
7854 stmt = begin_for_stmt ();
7855 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
7856 finish_for_init_stmt (stmt);
7857 finish_for_cond (tsubst_expr (FOR_COND (t),
7858 args, complain, in_decl),
7860 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
7861 finish_for_expr (tmp, stmt);
7862 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
7863 finish_for_stmt (stmt);
7870 stmt = begin_while_stmt ();
7871 finish_while_stmt_cond (tsubst_expr (WHILE_COND (t),
7872 args, complain, in_decl),
7874 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
7875 finish_while_stmt (stmt);
7882 stmt = begin_do_stmt ();
7883 tsubst_expr (DO_BODY (t), args, complain, in_decl);
7884 finish_do_body (stmt);
7885 finish_do_stmt (tsubst_expr (DO_COND (t),
7886 args, complain, in_decl),
7894 stmt = begin_if_stmt ();
7895 finish_if_stmt_cond (tsubst_expr (IF_COND (t),
7896 args, complain, in_decl),
7899 if (tmp = THEN_CLAUSE (t), tmp)
7901 tsubst_expr (tmp, args, complain, in_decl);
7902 finish_then_clause (stmt);
7905 if (tmp = ELSE_CLAUSE (t), tmp)
7907 begin_else_clause ();
7908 tsubst_expr (tmp, args, complain, in_decl);
7909 finish_else_clause (stmt);
7919 if (COMPOUND_STMT_BODY_BLOCK (t))
7920 stmt = begin_function_body ();
7922 stmt = begin_compound_stmt (COMPOUND_STMT_NO_SCOPE (t));
7924 tsubst_expr (COMPOUND_BODY (t), args,
7925 complain | ((stmt_expr & tf_stmt_expr_cmpd) << 1),
7928 if (COMPOUND_STMT_BODY_BLOCK (t))
7929 finish_function_body (stmt);
7931 finish_compound_stmt (stmt);
7937 finish_break_stmt ();
7942 finish_continue_stmt ();
7950 stmt = begin_switch_stmt ();
7951 val = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
7952 finish_switch_cond (val, stmt);
7953 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
7954 finish_switch_stmt (stmt);
7960 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
7961 tsubst_expr (CASE_HIGH (t), args, complain,
7966 input_line = STMT_LINENO (t);
7967 finish_label_stmt (DECL_NAME (LABEL_STMT_LABEL (t)));
7971 input_filename = FILE_STMT_FILENAME (t);
7972 add_stmt (build_nt (FILE_STMT, FILE_STMT_FILENAME_NODE (t)));
7977 tmp = GOTO_DESTINATION (t);
7978 if (TREE_CODE (tmp) != LABEL_DECL)
7979 /* Computed goto's must be tsubst'd into. On the other hand,
7980 non-computed gotos must not be; the identifier in question
7981 will have no binding. */
7982 tmp = tsubst_expr (tmp, args, complain, in_decl);
7984 tmp = DECL_NAME (tmp);
7985 finish_goto_stmt (tmp);
7990 tmp = finish_asm_stmt
7992 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
7993 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
7994 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
7995 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
7996 ASM_INPUT_P (tmp) = ASM_INPUT_P (t);
8003 stmt = begin_try_block ();
8004 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8005 finish_cleanup_try_block (stmt);
8006 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8012 if (FN_TRY_BLOCK_P (t))
8013 stmt = begin_function_try_block ();
8015 stmt = begin_try_block ();
8017 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8019 if (FN_TRY_BLOCK_P (t))
8020 finish_function_try_block (stmt);
8022 finish_try_block (stmt);
8024 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8025 if (FN_TRY_BLOCK_P (t))
8026 finish_function_handler_sequence (stmt);
8028 finish_handler_sequence (stmt);
8037 stmt = begin_handler ();
8038 if (HANDLER_PARMS (t))
8040 decl = DECL_STMT_DECL (HANDLER_PARMS (t));
8041 decl = tsubst (decl, args, complain, in_decl);
8042 /* Prevent instantiate_decl from trying to instantiate
8043 this variable. We've already done all that needs to be
8045 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8049 finish_handler_parms (decl, stmt);
8050 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8051 finish_handler (stmt);
8057 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8064 return tsubst_expr (TREE_CHAIN (t), args, complain | stmt_expr, in_decl);
8067 /* T is a postfix-expression that is not being used in a function
8068 call. Return the substituted version of T. */
8071 tsubst_non_call_postfix_expression (tree t, tree args,
8072 tsubst_flags_t complain,
8075 if (TREE_CODE (t) == SCOPE_REF)
8076 t = tsubst_qualified_id (t, args, complain, in_decl,
8077 /*done=*/false, /*address_p=*/false);
8079 t = tsubst_copy_and_build (t, args, complain, in_decl,
8080 /*function_p=*/false);
8085 /* Like tsubst but deals with expressions and performs semantic
8086 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8089 tsubst_copy_and_build (tree t,
8091 tsubst_flags_t complain,
8095 #define RECUR(NODE) \
8096 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8100 if (t == NULL_TREE || t == error_mark_node)
8103 switch (TREE_CODE (t))
8108 case IDENTIFIER_NODE:
8112 tree qualifying_class;
8113 bool non_integral_constant_expression_p;
8114 const char *error_msg;
8116 if (IDENTIFIER_TYPENAME_P (t))
8118 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8119 t = mangle_conv_op_name_for_type (new_type);
8122 /* Look up the name. */
8123 decl = lookup_name (t, 0);
8125 /* By convention, expressions use ERROR_MARK_NODE to indicate
8126 failure, not NULL_TREE. */
8127 if (decl == NULL_TREE)
8128 decl = error_mark_node;
8130 decl = finish_id_expression (t, decl, NULL_TREE,
8133 /*integral_constant_expression_p=*/false,
8134 /*allow_non_integral_constant_expression_p=*/false,
8135 &non_integral_constant_expression_p,
8139 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8140 decl = unqualified_name_lookup_error (decl);
8144 case TEMPLATE_ID_EXPR:
8147 tree template = RECUR (TREE_OPERAND (t, 0));
8148 tree targs = TREE_OPERAND (t, 1);
8151 targs = tsubst_template_args (targs, args, complain, in_decl);
8153 if (TREE_CODE (template) == COMPONENT_REF)
8155 object = TREE_OPERAND (template, 0);
8156 template = TREE_OPERAND (template, 1);
8160 template = lookup_template_function (template, targs);
8163 return build (COMPONENT_REF, TREE_TYPE (template),
8170 return build_x_indirect_ref (RECUR (TREE_OPERAND (t, 0)), "unary *");
8173 return build_functional_cast
8174 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8175 RECUR (TREE_OPERAND (t, 0)));
8177 case REINTERPRET_CAST_EXPR:
8178 return build_reinterpret_cast
8179 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8180 RECUR (TREE_OPERAND (t, 0)));
8182 case CONST_CAST_EXPR:
8183 return build_const_cast
8184 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8185 RECUR (TREE_OPERAND (t, 0)));
8187 case DYNAMIC_CAST_EXPR:
8188 return build_dynamic_cast
8189 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8190 RECUR (TREE_OPERAND (t, 0)));
8192 case STATIC_CAST_EXPR:
8193 return build_static_cast
8194 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8195 RECUR (TREE_OPERAND (t, 0)));
8197 case POSTDECREMENT_EXPR:
8198 case POSTINCREMENT_EXPR:
8199 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8200 args, complain, in_decl);
8201 return build_x_unary_op (TREE_CODE (t), op1);
8203 case PREDECREMENT_EXPR:
8204 case PREINCREMENT_EXPR:
8208 case TRUTH_NOT_EXPR:
8209 case CONVERT_EXPR: /* Unary + */
8212 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8215 op1 = TREE_OPERAND (t, 0);
8216 if (TREE_CODE (op1) == SCOPE_REF)
8217 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8218 /*done=*/true, /*address_p=*/true);
8220 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8222 if (TREE_CODE (op1) == LABEL_DECL)
8223 return finish_label_address_expr (DECL_NAME (op1));
8224 return build_x_unary_op (ADDR_EXPR, op1);
8229 case TRUNC_DIV_EXPR:
8231 case FLOOR_DIV_EXPR:
8232 case ROUND_DIV_EXPR:
8233 case EXACT_DIV_EXPR:
8237 case TRUNC_MOD_EXPR:
8238 case FLOOR_MOD_EXPR:
8239 case TRUTH_ANDIF_EXPR:
8240 case TRUTH_ORIF_EXPR:
8241 case TRUTH_AND_EXPR:
8257 return build_x_binary_op
8259 RECUR (TREE_OPERAND (t, 0)),
8260 RECUR (TREE_OPERAND (t, 1)));
8263 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8264 /*address_p=*/false);
8267 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8270 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)));
8272 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8273 args, complain, in_decl);
8274 /* Remember that there was a reference to this entity. */
8277 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8281 op1 = TREE_OPERAND (t, 0);
8284 /* When there are no ARGS, we are trying to evaluate a
8285 non-dependent expression from the parser. Trying to do
8286 the substitutions may not work. */
8288 op1 = TREE_TYPE (op1);
8297 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8299 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8302 return build_x_modify_expr
8303 (RECUR (TREE_OPERAND (t, 0)),
8304 TREE_CODE (TREE_OPERAND (t, 1)),
8305 RECUR (TREE_OPERAND (t, 2)));
8308 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8309 args, complain, in_decl);
8310 /* Remember that there was a reference to this entity. */
8313 return build_x_arrow (op1);
8317 (RECUR (TREE_OPERAND (t, 0)),
8318 RECUR (TREE_OPERAND (t, 1)),
8319 RECUR (TREE_OPERAND (t, 2)),
8320 NEW_EXPR_USE_GLOBAL (t));
8323 return delete_sanity
8324 (RECUR (TREE_OPERAND (t, 0)),
8325 RECUR (TREE_OPERAND (t, 1)),
8326 DELETE_EXPR_USE_VEC (t),
8327 DELETE_EXPR_USE_GLOBAL (t));
8330 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8331 RECUR (TREE_OPERAND (t, 1)));
8340 function = TREE_OPERAND (t, 0);
8341 /* When we parsed the expression, we determined whether or
8342 not Koenig lookup should be performed. */
8343 koenig_p = KOENIG_LOOKUP_P (t);
8344 if (TREE_CODE (function) == SCOPE_REF)
8347 function = tsubst_qualified_id (function, args, complain, in_decl,
8349 /*address_p=*/false);
8353 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8354 && (TREE_CODE (TREE_OPERAND (function, 1))
8356 function = tsubst_copy_and_build (function, args, complain,
8359 if (BASELINK_P (function))
8363 call_args = RECUR (TREE_OPERAND (t, 1));
8365 /* We do not perform argument-dependent lookup if normal
8366 lookup finds a non-function, in accordance with the
8367 expected resolution of DR 218. */
8369 && (is_overloaded_fn (function)
8370 || TREE_CODE (function) == IDENTIFIER_NODE))
8371 function = perform_koenig_lookup (function, call_args);
8373 if (TREE_CODE (function) == IDENTIFIER_NODE)
8375 unqualified_name_lookup_error (function);
8376 return error_mark_node;
8379 /* Remember that there was a reference to this entity. */
8380 if (DECL_P (function))
8381 mark_used (function);
8383 function = convert_from_reference (function);
8385 if (TREE_CODE (function) == OFFSET_REF)
8386 return build_offset_ref_call_from_tree (function, call_args);
8387 if (TREE_CODE (function) == COMPONENT_REF)
8389 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8390 return finish_call_expr (function, call_args,
8391 /*disallow_virtual=*/false,
8392 /*koenig_p=*/false);
8394 return (build_new_method_call
8395 (TREE_OPERAND (function, 0),
8396 TREE_OPERAND (function, 1),
8397 call_args, NULL_TREE,
8398 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8400 return finish_call_expr (function, call_args,
8401 /*disallow_virtual=*/qualified_p,
8406 return build_x_conditional_expr
8407 (RECUR (TREE_OPERAND (t, 0)),
8408 RECUR (TREE_OPERAND (t, 1)),
8409 RECUR (TREE_OPERAND (t, 2)));
8411 case PSEUDO_DTOR_EXPR:
8412 return finish_pseudo_destructor_expr
8413 (RECUR (TREE_OPERAND (t, 0)),
8414 RECUR (TREE_OPERAND (t, 1)),
8415 RECUR (TREE_OPERAND (t, 2)));
8419 tree purpose, value, chain;
8421 if (t == void_list_node)
8424 purpose = TREE_PURPOSE (t);
8426 purpose = RECUR (purpose);
8427 value = TREE_VALUE (t);
8429 value = RECUR (value);
8430 chain = TREE_CHAIN (t);
8431 if (chain && chain != void_type_node)
8432 chain = RECUR (chain);
8433 if (purpose == TREE_PURPOSE (t)
8434 && value == TREE_VALUE (t)
8435 && chain == TREE_CHAIN (t))
8437 return tree_cons (purpose, value, chain);
8445 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8446 args, complain, in_decl);
8447 /* Remember that there was a reference to this entity. */
8448 if (DECL_P (object))
8451 member = TREE_OPERAND (t, 1);
8452 if (BASELINK_P (member))
8453 member = tsubst_baselink (member,
8454 non_reference (TREE_TYPE (object)),
8455 args, complain, in_decl);
8457 member = tsubst_copy (member, args, complain, in_decl);
8459 if (!CLASS_TYPE_P (TREE_TYPE (object)))
8461 if (TREE_CODE (member) == BIT_NOT_EXPR)
8462 return finish_pseudo_destructor_expr (object,
8464 TREE_TYPE (object));
8465 else if (TREE_CODE (member) == SCOPE_REF
8466 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8467 return finish_pseudo_destructor_expr (object,
8469 TREE_TYPE (object));
8471 else if (TREE_CODE (member) == SCOPE_REF
8472 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8477 /* Lookup the template functions now that we know what the
8479 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8480 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8481 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8482 /*is_type_p=*/false,
8483 /*complain=*/false);
8484 if (BASELINK_P (member))
8485 BASELINK_FUNCTIONS (member)
8486 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8490 qualified_name_lookup_error (TREE_TYPE (object), tmpl);
8491 return error_mark_node;
8494 else if (TREE_CODE (member) == FIELD_DECL)
8495 return finish_non_static_data_member (member, object, NULL_TREE);
8497 return finish_class_member_access_expr (object, member);
8502 (RECUR (TREE_OPERAND (t, 0)));
8508 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8511 /* digest_init will do the wrong thing if we let it. */
8512 if (type && TYPE_PTRMEMFUNC_P (type))
8516 /* We do not want to process the purpose of aggregate
8517 initializers as they are identifier nodes which will be
8518 looked up by digest_init. */
8519 purpose_p = !(type && IS_AGGR_TYPE (type));
8520 for (elts = CONSTRUCTOR_ELTS (t);
8522 elts = TREE_CHAIN (elts))
8524 tree purpose = TREE_PURPOSE (elts);
8525 tree value = TREE_VALUE (elts);
8527 if (purpose && purpose_p)
8528 purpose = RECUR (purpose);
8529 value = RECUR (value);
8530 r = tree_cons (purpose, value, r);
8533 r = build_constructor (NULL_TREE, nreverse (r));
8534 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8537 return digest_init (type, r, 0);
8543 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8544 if (TYPE_P (operand_0))
8545 return get_typeid (operand_0);
8546 return build_typeid (operand_0);
8550 return convert_from_reference (tsubst_copy (t, args, complain, in_decl));
8554 t = tsubst_copy (t, args, complain, in_decl);
8555 return convert_from_reference (t);
8558 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8559 tsubst_copy (TREE_TYPE (t), args, complain,
8563 return tsubst_copy (t, args, complain, in_decl);
8569 /* Verify that the instantiated ARGS are valid. For type arguments,
8570 make sure that the type's linkage is ok. For non-type arguments,
8571 make sure they are constants if they are integral or enumerations.
8572 Emit an error under control of COMPLAIN, and return TRUE on error. */
8575 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8577 int ix, len = DECL_NTPARMS (tmpl);
8578 bool result = false;
8580 for (ix = 0; ix != len; ix++)
8582 tree t = TREE_VEC_ELT (args, ix);
8586 /* [basic.link]: A name with no linkage (notably, the name
8587 of a class or enumeration declared in a local scope)
8588 shall not be used to declare an entity with linkage.
8589 This implies that names with no linkage cannot be used as
8590 template arguments. */
8591 tree nt = no_linkage_check (t);
8595 if (!(complain & tf_error))
8597 else if (TYPE_ANONYMOUS_P (nt))
8598 error ("`%T' uses anonymous type", t);
8600 error ("`%T' uses local type `%T'", t, nt);
8603 /* In order to avoid all sorts of complications, we do not
8604 allow variably-modified types as template arguments. */
8605 else if (variably_modified_type_p (t))
8607 if (complain & tf_error)
8608 error ("`%T' is a variably modified type", t);
8612 /* A non-type argument of integral or enumerated type must be a
8614 else if (TREE_TYPE (t)
8615 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8616 && !TREE_CONSTANT (t))
8618 if (complain & tf_error)
8619 error ("integral expression `%E' is not constant", t);
8623 if (result && complain & tf_error)
8624 error (" trying to instantiate `%D'", tmpl);
8628 /* Instantiate the indicated variable or function template TMPL with
8629 the template arguments in TARG_PTR. */
8632 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8638 if (tmpl == error_mark_node)
8639 return error_mark_node;
8641 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 283);
8643 /* If this function is a clone, handle it specially. */
8644 if (DECL_CLONED_FUNCTION_P (tmpl))
8646 tree spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8650 /* Look for the clone. */
8651 for (clone = TREE_CHAIN (spec);
8652 clone && DECL_CLONED_FUNCTION_P (clone);
8653 clone = TREE_CHAIN (clone))
8654 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8656 /* We should always have found the clone by now. */
8661 /* Check to see if we already have this specialization. */
8662 spec = retrieve_specialization (tmpl, targ_ptr);
8663 if (spec != NULL_TREE)
8666 gen_tmpl = most_general_template (tmpl);
8667 if (tmpl != gen_tmpl)
8669 /* The TMPL is a partial instantiation. To get a full set of
8670 arguments we must add the arguments used to perform the
8671 partial instantiation. */
8672 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
8675 /* Check to see if we already have this specialization. */
8676 spec = retrieve_specialization (gen_tmpl, targ_ptr);
8677 if (spec != NULL_TREE)
8681 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
8683 return error_mark_node;
8685 /* We are building a FUNCTION_DECL, during which the access of its
8686 parameters and return types have to be checked. However this
8687 FUNCTION_DECL which is the desired context for access checking
8688 is not built yet. We solve this chicken-and-egg problem by
8689 deferring all checks until we have the FUNCTION_DECL. */
8690 push_deferring_access_checks (dk_deferred);
8692 /* Substitute template parameters. */
8693 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
8694 targ_ptr, complain, gen_tmpl);
8696 /* Now we know the specialization, compute access previously
8698 push_access_scope (fndecl);
8699 perform_deferred_access_checks ();
8700 pop_access_scope (fndecl);
8701 pop_deferring_access_checks ();
8703 /* The DECL_TI_TEMPLATE should always be the immediate parent
8704 template, not the most general template. */
8705 DECL_TI_TEMPLATE (fndecl) = tmpl;
8707 /* If we've just instantiated the main entry point for a function,
8708 instantiate all the alternate entry points as well. We do this
8709 by cloning the instantiation of the main entry point, not by
8710 instantiating the template clones. */
8711 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
8712 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
8717 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8718 arguments that are being used when calling it. TARGS is a vector
8719 into which the deduced template arguments are placed.
8721 Return zero for success, 2 for an incomplete match that doesn't resolve
8722 all the types, and 1 for complete failure. An error message will be
8723 printed only for an incomplete match.
8725 If FN is a conversion operator, or we are trying to produce a specific
8726 specialization, RETURN_TYPE is the return type desired.
8728 The EXPLICIT_TARGS are explicit template arguments provided via a
8731 The parameter STRICT is one of:
8734 We are deducing arguments for a function call, as in
8738 We are deducing arguments for a conversion function, as in
8742 We are deducing arguments when doing an explicit instantiation
8743 as in [temp.explicit], when determining an explicit specialization
8744 as in [temp.expl.spec], or when taking the address of a function
8745 template, as in [temp.deduct.funcaddr].
8748 We are deducing arguments when calculating the partial
8749 ordering between specializations of function or class
8750 templates, as in [temp.func.order] and [temp.class.order].
8752 LEN is the number of parms to consider before returning success, or -1
8753 for all. This is used in partial ordering to avoid comparing parms for
8754 which no actual argument was passed, since they are not considered in
8755 overload resolution (and are explicitly excluded from consideration in
8756 partial ordering in [temp.func.order]/6). */
8759 fn_type_unification (tree fn,
8760 tree explicit_targs,
8764 unification_kind_t strict,
8771 my_friendly_assert (TREE_CODE (fn) == TEMPLATE_DECL, 0);
8773 fntype = TREE_TYPE (fn);
8778 The specified template arguments must match the template
8779 parameters in kind (i.e., type, nontype, template), and there
8780 must not be more arguments than there are parameters;
8781 otherwise type deduction fails.
8783 Nontype arguments must match the types of the corresponding
8784 nontype template parameters, or must be convertible to the
8785 types of the corresponding nontype parameters as specified in
8786 _temp.arg.nontype_, otherwise type deduction fails.
8788 All references in the function type of the function template
8789 to the corresponding template parameters are replaced by the
8790 specified template argument values. If a substitution in a
8791 template parameter or in the function type of the function
8792 template results in an invalid type, type deduction fails. */
8794 tree converted_args;
8798 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8799 explicit_targs, NULL_TREE, tf_none,
8800 /*require_all_arguments=*/0));
8801 if (converted_args == error_mark_node)
8804 /* Substitute the explicit args into the function type. This is
8805 necessary so that, for instance, explicitly declared function
8806 arguments can match null pointed constants. If we were given
8807 an incomplete set of explicit args, we must not do semantic
8808 processing during substitution as we could create partial
8810 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
8811 processing_template_decl += incomplete;
8812 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
8813 processing_template_decl -= incomplete;
8815 if (fntype == error_mark_node)
8818 /* Place the explicitly specified arguments in TARGS. */
8819 for (i = NUM_TMPL_ARGS (converted_args); i--;)
8820 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
8823 parms = TYPE_ARG_TYPES (fntype);
8824 /* Never do unification on the 'this' parameter. */
8825 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
8826 parms = TREE_CHAIN (parms);
8830 /* We've been given a return type to match, prepend it. */
8831 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
8832 args = tree_cons (NULL_TREE, return_type, args);
8837 /* We allow incomplete unification without an error message here
8838 because the standard doesn't seem to explicitly prohibit it. Our
8839 callers must be ready to deal with unification failures in any
8841 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8842 targs, parms, args, /*subr=*/0,
8843 strict, /*allow_incomplete*/1, len);
8846 /* All is well so far. Now, check:
8850 When all template arguments have been deduced, all uses of
8851 template parameters in nondeduced contexts are replaced with
8852 the corresponding deduced argument values. If the
8853 substitution results in an invalid type, as described above,
8854 type deduction fails. */
8855 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
8862 /* Adjust types before performing type deduction, as described in
8863 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
8864 sections are symmetric. PARM is the type of a function parameter
8865 or the return type of the conversion function. ARG is the type of
8866 the argument passed to the call, or the type of the value
8867 initialized with the result of the conversion function. */
8870 maybe_adjust_types_for_deduction (unification_kind_t strict,
8883 /* Swap PARM and ARG throughout the remainder of this
8884 function; the handling is precisely symmetric since PARM
8885 will initialize ARG rather than vice versa. */
8893 /* There is nothing to do in this case. */
8897 /* DR 214. [temp.func.order] is underspecified, and leads to no
8898 ordering between things like `T *' and `T const &' for `U *'.
8899 The former has T=U and the latter T=U*. The former looks more
8900 specialized and John Spicer considers it well-formed (the EDG
8901 compiler accepts it).
8903 John also confirms that deduction should proceed as in a function
8904 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
8905 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
8906 to an actual call can have such a type.
8908 If both ARG and PARM are REFERENCE_TYPE, we change neither.
8909 If only ARG is a REFERENCE_TYPE, we look through that and then
8910 proceed as with DEDUCE_CALL (which could further convert it). */
8911 if (TREE_CODE (*arg) == REFERENCE_TYPE)
8913 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8915 *arg = TREE_TYPE (*arg);
8922 if (TREE_CODE (*parm) != REFERENCE_TYPE)
8924 /* [temp.deduct.call]
8926 If P is not a reference type:
8928 --If A is an array type, the pointer type produced by the
8929 array-to-pointer standard conversion (_conv.array_) is
8930 used in place of A for type deduction; otherwise,
8932 --If A is a function type, the pointer type produced by
8933 the function-to-pointer standard conversion
8934 (_conv.func_) is used in place of A for type deduction;
8937 --If A is a cv-qualified type, the top level
8938 cv-qualifiers of A's type are ignored for type
8940 if (TREE_CODE (*arg) == ARRAY_TYPE)
8941 *arg = build_pointer_type (TREE_TYPE (*arg));
8942 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
8943 *arg = build_pointer_type (*arg);
8945 *arg = TYPE_MAIN_VARIANT (*arg);
8948 /* [temp.deduct.call]
8950 If P is a cv-qualified type, the top level cv-qualifiers
8951 of P's type are ignored for type deduction. If P is a
8952 reference type, the type referred to by P is used for
8954 *parm = TYPE_MAIN_VARIANT (*parm);
8955 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8957 *parm = TREE_TYPE (*parm);
8958 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
8961 /* DR 322. For conversion deduction, remove a reference type on parm
8962 too (which has been swapped into ARG). */
8963 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
8964 *arg = TREE_TYPE (*arg);
8969 /* Most parms like fn_type_unification.
8971 If SUBR is 1, we're being called recursively (to unify the
8972 arguments of a function or method parameter of a function
8976 type_unification_real (tree tparms,
8981 unification_kind_t strict,
8982 int allow_incomplete,
8987 int ntparms = TREE_VEC_LENGTH (tparms);
8989 int saw_undeduced = 0;
8993 my_friendly_assert (TREE_CODE (tparms) == TREE_VEC, 289);
8994 my_friendly_assert (xparms == NULL_TREE
8995 || TREE_CODE (xparms) == TREE_LIST, 290);
8996 my_friendly_assert (!xargs || TREE_CODE (xargs) == TREE_LIST, 291);
8997 my_friendly_assert (ntparms > 0, 292);
9002 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9003 | UNIFY_ALLOW_DERIVED);
9007 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9011 sub_strict = UNIFY_ALLOW_NONE;
9015 sub_strict = UNIFY_ALLOW_NONE;
9031 && parms != void_list_node
9033 && args != void_list_node)
9035 parm = TREE_VALUE (parms);
9036 parms = TREE_CHAIN (parms);
9037 arg = TREE_VALUE (args);
9038 args = TREE_CHAIN (args);
9040 if (arg == error_mark_node)
9042 if (arg == unknown_type_node)
9043 /* We can't deduce anything from this, but we might get all the
9044 template args from other function args. */
9047 /* Conversions will be performed on a function argument that
9048 corresponds with a function parameter that contains only
9049 non-deducible template parameters and explicitly specified
9050 template parameters. */
9051 if (!uses_template_parms (parm))
9056 type = TREE_TYPE (arg);
9060 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
9062 if (same_type_p (parm, type))
9066 /* It might work; we shouldn't check now, because we might
9067 get into infinite recursion. Overload resolution will
9076 my_friendly_assert (TREE_TYPE (arg) != NULL_TREE, 293);
9077 if (type_unknown_p (arg))
9079 /* [temp.deduct.type] A template-argument can be deduced from
9080 a pointer to function or pointer to member function
9081 argument if the set of overloaded functions does not
9082 contain function templates and at most one of a set of
9083 overloaded functions provides a unique match. */
9085 if (resolve_overloaded_unification
9086 (tparms, targs, parm, arg, strict, sub_strict)
9091 arg = TREE_TYPE (arg);
9092 if (arg == error_mark_node)
9097 int arg_strict = sub_strict;
9100 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9102 if (unify (tparms, targs, parm, arg, arg_strict))
9106 /* Are we done with the interesting parms? */
9110 /* Fail if we've reached the end of the parm list, and more args
9111 are present, and the parm list isn't variadic. */
9112 if (args && args != void_list_node && parms == void_list_node)
9114 /* Fail if parms are left and they don't have default values. */
9116 && parms != void_list_node
9117 && TREE_PURPOSE (parms) == NULL_TREE)
9122 for (i = 0; i < ntparms; i++)
9123 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
9125 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9127 /* If this is an undeduced nontype parameter that depends on
9128 a type parameter, try another pass; its type may have been
9129 deduced from a later argument than the one from which
9130 this parameter can be deduced. */
9131 if (TREE_CODE (tparm) == PARM_DECL
9132 && uses_template_parms (TREE_TYPE (tparm))
9133 && !saw_undeduced++)
9136 if (!allow_incomplete)
9137 error ("incomplete type unification");
9143 /* Subroutine of type_unification_real. Args are like the variables at the
9144 call site. ARG is an overloaded function (or template-id); we try
9145 deducing template args from each of the overloads, and if only one
9146 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9149 resolve_overloaded_unification (tree tparms,
9153 unification_kind_t strict,
9156 tree tempargs = copy_node (targs);
9160 if (TREE_CODE (arg) == ADDR_EXPR)
9162 arg = TREE_OPERAND (arg, 0);
9168 if (TREE_CODE (arg) == COMPONENT_REF)
9169 /* Handle `&x' where `x' is some static or non-static member
9171 arg = TREE_OPERAND (arg, 1);
9173 if (TREE_CODE (arg) == OFFSET_REF)
9174 arg = TREE_OPERAND (arg, 1);
9176 /* Strip baselink information. */
9177 if (BASELINK_P (arg))
9178 arg = BASELINK_FUNCTIONS (arg);
9180 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9182 /* If we got some explicit template args, we need to plug them into
9183 the affected templates before we try to unify, in case the
9184 explicit args will completely resolve the templates in question. */
9186 tree expl_subargs = TREE_OPERAND (arg, 1);
9187 arg = TREE_OPERAND (arg, 0);
9189 for (; arg; arg = OVL_NEXT (arg))
9191 tree fn = OVL_CURRENT (arg);
9194 if (TREE_CODE (fn) != TEMPLATE_DECL)
9197 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
9201 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9202 good += try_one_overload (tparms, targs, tempargs, parm,
9203 elem, strict, sub_strict, addr_p);
9207 else if (TREE_CODE (arg) == OVERLOAD
9208 || TREE_CODE (arg) == FUNCTION_DECL)
9210 for (; arg; arg = OVL_NEXT (arg))
9211 good += try_one_overload (tparms, targs, tempargs, parm,
9212 TREE_TYPE (OVL_CURRENT (arg)),
9213 strict, sub_strict, addr_p);
9218 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9219 to function or pointer to member function argument if the set of
9220 overloaded functions does not contain function templates and at most
9221 one of a set of overloaded functions provides a unique match.
9223 So if we found multiple possibilities, we return success but don't
9228 int i = TREE_VEC_LENGTH (targs);
9230 if (TREE_VEC_ELT (tempargs, i))
9231 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9239 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9240 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9241 different overloads deduce different arguments for a given parm.
9242 ADDR_P is true if the expression for which deduction is being
9243 performed was of the form "& fn" rather than simply "fn".
9245 Returns 1 on success. */
9248 try_one_overload (tree tparms,
9253 unification_kind_t strict,
9261 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9262 to function or pointer to member function argument if the set of
9263 overloaded functions does not contain function templates and at most
9264 one of a set of overloaded functions provides a unique match.
9266 So if this is a template, just return success. */
9268 if (uses_template_parms (arg))
9271 if (TREE_CODE (arg) == METHOD_TYPE)
9272 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9274 arg = build_pointer_type (arg);
9276 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9278 /* We don't copy orig_targs for this because if we have already deduced
9279 some template args from previous args, unify would complain when we
9280 try to deduce a template parameter for the same argument, even though
9281 there isn't really a conflict. */
9282 nargs = TREE_VEC_LENGTH (targs);
9283 tempargs = make_tree_vec (nargs);
9285 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9288 /* First make sure we didn't deduce anything that conflicts with
9289 explicitly specified args. */
9290 for (i = nargs; i--; )
9292 tree elt = TREE_VEC_ELT (tempargs, i);
9293 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9295 if (elt == NULL_TREE)
9297 else if (uses_template_parms (elt))
9299 /* Since we're unifying against ourselves, we will fill in template
9300 args used in the function parm list with our own template parms.
9302 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9305 else if (oldelt && ! template_args_equal (oldelt, elt))
9309 for (i = nargs; i--; )
9311 tree elt = TREE_VEC_ELT (tempargs, i);
9314 TREE_VEC_ELT (targs, i) = elt;
9320 /* Verify that nondeduce template argument agrees with the type
9321 obtained from argument deduction. Return nonzero if the
9326 struct A { typedef int X; };
9327 template <class T, class U> struct C {};
9328 template <class T> struct C<T, typename T::X> {};
9330 Then with the instantiation `C<A, int>', we can deduce that
9331 `T' is `A' but unify () does not check whether `typename T::X'
9332 is `int'. This function ensure that they agree.
9334 TARGS, PARMS are the same as the arguments of unify.
9335 ARGS contains template arguments from all levels. */
9338 verify_class_unification (tree targs, tree parms, tree args)
9340 parms = tsubst (parms, add_outermost_template_args (args, targs),
9341 tf_none, NULL_TREE);
9342 if (parms == error_mark_node)
9345 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9348 /* PARM is a template class (perhaps with unbound template
9349 parameters). ARG is a fully instantiated type. If ARG can be
9350 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9351 TARGS are as for unify. */
9354 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9358 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9359 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9360 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9363 /* We need to make a new template argument vector for the call to
9364 unify. If we used TARGS, we'd clutter it up with the result of
9365 the attempted unification, even if this class didn't work out.
9366 We also don't want to commit ourselves to all the unifications
9367 we've already done, since unification is supposed to be done on
9368 an argument-by-argument basis. In other words, consider the
9369 following pathological case:
9371 template <int I, int J, int K>
9374 template <int I, int J>
9375 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9377 template <int I, int J, int K>
9378 void f(S<I, J, K>, S<I, I, I>);
9387 Now, by the time we consider the unification involving `s2', we
9388 already know that we must have `f<0, 0, 0>'. But, even though
9389 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9390 because there are two ways to unify base classes of S<0, 1, 2>
9391 with S<I, I, I>. If we kept the already deduced knowledge, we
9392 would reject the possibility I=1. */
9393 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9395 /* If unification failed, we're done. */
9396 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9397 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9403 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
9404 have already discovered to be satisfactory. ARG_BINFO is the binfo
9405 for the base class of ARG that we are currently examining. */
9408 get_template_base_recursive (tree tparms,
9417 tree arg = BINFO_TYPE (arg_binfo);
9419 if (!(flags & GTB_IGNORE_TYPE))
9421 tree r = try_class_unification (tparms, targs,
9424 /* If there is more than one satisfactory baseclass, then:
9428 If they yield more than one possible deduced A, the type
9432 if (r && rval && !same_type_p (r, rval))
9433 return error_mark_node;
9438 binfos = BINFO_BASETYPES (arg_binfo);
9439 n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
9441 /* Process base types. */
9442 for (i = 0; i < n_baselinks; i++)
9444 tree base_binfo = TREE_VEC_ELT (binfos, i);
9447 /* Skip this base, if we've already seen it. */
9448 if (BINFO_MARKED (base_binfo))
9452 (flags & GTB_VIA_VIRTUAL) || TREE_VIA_VIRTUAL (base_binfo);
9454 /* When searching for a non-virtual, we cannot mark virtually
9457 BINFO_MARKED (base_binfo) = 1;
9459 rval = get_template_base_recursive (tparms, targs,
9463 GTB_VIA_VIRTUAL * this_virtual);
9465 /* If we discovered more than one matching base class, we can
9467 if (rval == error_mark_node)
9468 return error_mark_node;
9474 /* Given a template type PARM and a class type ARG, find the unique
9475 base type in ARG that is an instance of PARM. We do not examine
9476 ARG itself; only its base-classes. If there is no appropriate base
9477 class, return NULL_TREE. If there is more than one, return
9478 error_mark_node. PARM may be the type of a partial specialization,
9479 as well as a plain template type. Used by unify. */
9482 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9487 my_friendly_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)), 92);
9489 arg_binfo = TYPE_BINFO (complete_type (arg));
9490 rval = get_template_base_recursive (tparms, targs,
9495 /* Since get_template_base_recursive marks the bases classes, we
9496 must unmark them here. */
9497 dfs_walk (arg_binfo, dfs_unmark, markedp, 0);
9502 /* Returns the level of DECL, which declares a template parameter. */
9505 template_decl_level (tree decl)
9507 switch (TREE_CODE (decl))
9511 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9514 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9522 /* Decide whether ARG can be unified with PARM, considering only the
9523 cv-qualifiers of each type, given STRICT as documented for unify.
9524 Returns nonzero iff the unification is OK on that basis.*/
9527 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9529 int arg_quals = cp_type_quals (arg);
9530 int parm_quals = cp_type_quals (parm);
9532 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM)
9534 /* If the cvr quals of parm will not unify with ARG, they'll be
9535 ignored in instantiation, so we have to do the same here. */
9536 if (TREE_CODE (arg) == REFERENCE_TYPE)
9537 parm_quals &= ~(TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE);
9538 if (!POINTER_TYPE_P (arg) &&
9539 TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9540 parm_quals &= ~TYPE_QUAL_RESTRICT;
9543 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9544 && (arg_quals & parm_quals) != parm_quals)
9547 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9548 && (parm_quals & arg_quals) != arg_quals)
9554 /* Takes parameters as for type_unification. Returns 0 if the
9555 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9556 bitwise or of the following flags:
9559 Require an exact match between PARM and ARG.
9560 UNIFY_ALLOW_MORE_CV_QUAL:
9561 Allow the deduced ARG to be more cv-qualified (by qualification
9562 conversion) than ARG.
9563 UNIFY_ALLOW_LESS_CV_QUAL:
9564 Allow the deduced ARG to be less cv-qualified than ARG.
9565 UNIFY_ALLOW_DERIVED:
9566 Allow the deduced ARG to be a template base class of ARG,
9567 or a pointer to a template base class of the type pointed to by
9569 UNIFY_ALLOW_INTEGER:
9570 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9571 case for more information.
9572 UNIFY_ALLOW_OUTER_LEVEL:
9573 This is the outermost level of a deduction. Used to determine validity
9574 of qualification conversions. A valid qualification conversion must
9575 have const qualified pointers leading up to the inner type which
9576 requires additional CV quals, except at the outer level, where const
9577 is not required [conv.qual]. It would be normal to set this flag in
9578 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9579 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9580 This is the outermost level of a deduction, and PARM can be more CV
9581 qualified at this point.
9582 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9583 This is the outermost level of a deduction, and PARM can be less CV
9584 qualified at this point.
9585 UNIFY_ALLOW_MAX_CORRECTION:
9586 This is an INTEGER_TYPE's maximum value. Used if the range may
9587 have been derived from a size specification, such as an array size.
9588 If the size was given by a nontype template parameter N, the maximum
9589 value will have the form N-1. The flag says that we can (and indeed
9590 must) unify N with (ARG + 1), an exception to the normal rules on
9594 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9599 int strict_in = strict;
9601 /* I don't think this will do the right thing with respect to types.
9602 But the only case I've seen it in so far has been array bounds, where
9603 signedness is the only information lost, and I think that will be
9605 while (TREE_CODE (parm) == NOP_EXPR)
9606 parm = TREE_OPERAND (parm, 0);
9608 if (arg == error_mark_node)
9610 if (arg == unknown_type_node)
9611 /* We can't deduce anything from this, but we might get all the
9612 template args from other function args. */
9615 /* If PARM uses template parameters, then we can't bail out here,
9616 even if ARG == PARM, since we won't record unifications for the
9617 template parameters. We might need them if we're trying to
9618 figure out which of two things is more specialized. */
9619 if (arg == parm && !uses_template_parms (parm))
9622 /* Immediately reject some pairs that won't unify because of
9623 cv-qualification mismatches. */
9624 if (TREE_CODE (arg) == TREE_CODE (parm)
9626 /* It is the elements of the array which hold the cv quals of an array
9627 type, and the elements might be template type parms. We'll check
9629 && TREE_CODE (arg) != ARRAY_TYPE
9630 /* We check the cv-qualifiers when unifying with template type
9631 parameters below. We want to allow ARG `const T' to unify with
9632 PARM `T' for example, when computing which of two templates
9633 is more specialized, for example. */
9634 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9635 && !check_cv_quals_for_unify (strict_in, arg, parm))
9638 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9639 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9640 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9641 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9642 strict &= ~UNIFY_ALLOW_DERIVED;
9643 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9644 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9645 strict &= ~UNIFY_ALLOW_MAX_CORRECTION;
9647 switch (TREE_CODE (parm))
9651 case UNBOUND_CLASS_TEMPLATE:
9652 /* In a type which contains a nested-name-specifier, template
9653 argument values cannot be deduced for template parameters used
9654 within the nested-name-specifier. */
9657 case TEMPLATE_TYPE_PARM:
9658 case TEMPLATE_TEMPLATE_PARM:
9659 case BOUND_TEMPLATE_TEMPLATE_PARM:
9660 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9662 if (TEMPLATE_TYPE_LEVEL (parm)
9663 != template_decl_level (tparm))
9664 /* The PARM is not one we're trying to unify. Just check
9665 to see if it matches ARG. */
9666 return (TREE_CODE (arg) == TREE_CODE (parm)
9667 && same_type_p (parm, arg)) ? 0 : 1;
9668 idx = TEMPLATE_TYPE_IDX (parm);
9669 targ = TREE_VEC_ELT (targs, idx);
9670 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9672 /* Check for mixed types and values. */
9673 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9674 && TREE_CODE (tparm) != TYPE_DECL)
9675 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9676 && TREE_CODE (tparm) != TEMPLATE_DECL))
9679 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9681 /* ARG must be constructed from a template class or a template
9682 template parameter. */
9683 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9684 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9688 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9689 tree parmvec = TYPE_TI_ARGS (parm);
9690 tree argvec = TYPE_TI_ARGS (arg);
9692 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9695 /* The parameter and argument roles have to be switched here
9696 in order to handle default arguments properly. For example,
9697 template<template <class> class TT> void f(TT<int>)
9698 should be able to accept vector<int> which comes from
9699 template <class T, class Allocator = allocator>
9702 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9706 /* Deduce arguments T, i from TT<T> or TT<i>.
9707 We check each element of PARMVEC and ARGVEC individually
9708 rather than the whole TREE_VEC since they can have
9709 different number of elements. */
9711 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9713 tree t = TREE_VEC_ELT (parmvec, i);
9715 if (unify (tparms, targs, t,
9716 TREE_VEC_ELT (argvec, i),
9721 arg = TYPE_TI_TEMPLATE (arg);
9723 /* Fall through to deduce template name. */
9726 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9727 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9729 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9731 /* Simple cases: Value already set, does match or doesn't. */
9732 if (targ != NULL_TREE && template_args_equal (targ, arg))
9739 /* If PARM is `const T' and ARG is only `int', we don't have
9740 a match unless we are allowing additional qualification.
9741 If ARG is `const int' and PARM is just `T' that's OK;
9742 that binds `const int' to `T'. */
9743 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
9747 /* Consider the case where ARG is `const volatile int' and
9748 PARM is `const T'. Then, T should be `volatile int'. */
9749 arg = cp_build_qualified_type_real
9750 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
9751 if (arg == error_mark_node)
9754 /* Simple cases: Value already set, does match or doesn't. */
9755 if (targ != NULL_TREE && same_type_p (targ, arg))
9760 /* Make sure that ARG is not a variable-sized array. (Note
9761 that were talking about variable-sized arrays (like
9762 `int[n]'), rather than arrays of unknown size (like
9763 `int[]').) We'll get very confused by such a type since
9764 the bound of the array will not be computable in an
9765 instantiation. Besides, such types are not allowed in
9766 ISO C++, so we can do as we please here. */
9767 if (variably_modified_type_p (arg))
9771 TREE_VEC_ELT (targs, idx) = arg;
9774 case TEMPLATE_PARM_INDEX:
9775 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9777 if (TEMPLATE_PARM_LEVEL (parm)
9778 != template_decl_level (tparm))
9779 /* The PARM is not one we're trying to unify. Just check
9780 to see if it matches ARG. */
9781 return !(TREE_CODE (arg) == TREE_CODE (parm)
9782 && cp_tree_equal (parm, arg));
9784 idx = TEMPLATE_PARM_IDX (parm);
9785 targ = TREE_VEC_ELT (targs, idx);
9788 return !cp_tree_equal (targ, arg);
9790 /* [temp.deduct.type] If, in the declaration of a function template
9791 with a non-type template-parameter, the non-type
9792 template-parameter is used in an expression in the function
9793 parameter-list and, if the corresponding template-argument is
9794 deduced, the template-argument type shall match the type of the
9795 template-parameter exactly, except that a template-argument
9796 deduced from an array bound may be of any integral type.
9797 The non-type parameter might use already deduced type parameters. */
9798 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
9799 if (!TREE_TYPE (arg))
9800 /* Template-parameter dependent expression. Just accept it for now.
9801 It will later be processed in convert_template_argument. */
9803 else if (same_type_p (TREE_TYPE (arg), tparm))
9805 else if ((strict & UNIFY_ALLOW_INTEGER)
9806 && (TREE_CODE (tparm) == INTEGER_TYPE
9807 || TREE_CODE (tparm) == BOOLEAN_TYPE))
9809 else if (uses_template_parms (tparm))
9810 /* We haven't deduced the type of this parameter yet. Try again
9816 TREE_VEC_ELT (targs, idx) = arg;
9821 /* A pointer-to-member constant can be unified only with
9822 another constant. */
9823 if (TREE_CODE (arg) != PTRMEM_CST)
9826 /* Just unify the class member. It would be useless (and possibly
9827 wrong, depending on the strict flags) to unify also
9828 PTRMEM_CST_CLASS, because we want to be sure that both parm and
9829 arg refer to the same variable, even if through different
9830 classes. For instance:
9832 struct A { int x; };
9835 Unification of &A::x and &B::x must succeed. */
9836 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
9837 PTRMEM_CST_MEMBER (arg), strict);
9842 if (TREE_CODE (arg) != POINTER_TYPE)
9845 /* [temp.deduct.call]
9847 A can be another pointer or pointer to member type that can
9848 be converted to the deduced A via a qualification
9849 conversion (_conv.qual_).
9851 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
9852 This will allow for additional cv-qualification of the
9853 pointed-to types if appropriate. */
9855 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
9856 /* The derived-to-base conversion only persists through one
9857 level of pointers. */
9858 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
9860 return unify (tparms, targs, TREE_TYPE (parm),
9861 TREE_TYPE (arg), strict);
9864 case REFERENCE_TYPE:
9865 if (TREE_CODE (arg) != REFERENCE_TYPE)
9867 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9868 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9871 if (TREE_CODE (arg) != ARRAY_TYPE)
9873 if ((TYPE_DOMAIN (parm) == NULL_TREE)
9874 != (TYPE_DOMAIN (arg) == NULL_TREE))
9876 if (TYPE_DOMAIN (parm) != NULL_TREE
9877 && unify (tparms, targs, TYPE_DOMAIN (parm),
9878 TYPE_DOMAIN (arg), UNIFY_ALLOW_NONE) != 0)
9880 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9881 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9889 if (TREE_CODE (arg) != TREE_CODE (parm))
9892 if (TREE_CODE (parm) == INTEGER_TYPE
9893 && TREE_CODE (TYPE_MAX_VALUE (parm)) != INTEGER_CST)
9895 if (TYPE_MIN_VALUE (parm) && TYPE_MIN_VALUE (arg)
9896 && unify (tparms, targs, TYPE_MIN_VALUE (parm),
9897 TYPE_MIN_VALUE (arg), UNIFY_ALLOW_INTEGER))
9899 if (TYPE_MAX_VALUE (parm) && TYPE_MAX_VALUE (arg)
9900 && unify (tparms, targs, TYPE_MAX_VALUE (parm),
9901 TYPE_MAX_VALUE (arg),
9902 UNIFY_ALLOW_INTEGER | UNIFY_ALLOW_MAX_CORRECTION))
9905 /* We have already checked cv-qualification at the top of the
9907 else if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
9910 /* As far as unification is concerned, this wins. Later checks
9911 will invalidate it if necessary. */
9914 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
9915 /* Type INTEGER_CST can come from ordinary constant template args. */
9917 while (TREE_CODE (arg) == NOP_EXPR)
9918 arg = TREE_OPERAND (arg, 0);
9920 if (TREE_CODE (arg) != INTEGER_CST)
9922 return !tree_int_cst_equal (parm, arg);
9927 if (TREE_CODE (arg) != TREE_VEC)
9929 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
9931 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
9932 if (unify (tparms, targs,
9933 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
9941 if (TREE_CODE (arg) != TREE_CODE (parm))
9944 if (TYPE_PTRMEMFUNC_P (parm))
9946 if (!TYPE_PTRMEMFUNC_P (arg))
9949 return unify (tparms, targs,
9950 TYPE_PTRMEMFUNC_FN_TYPE (parm),
9951 TYPE_PTRMEMFUNC_FN_TYPE (arg),
9955 if (CLASSTYPE_TEMPLATE_INFO (parm))
9959 if (strict_in & UNIFY_ALLOW_DERIVED)
9961 /* First, we try to unify the PARM and ARG directly. */
9962 t = try_class_unification (tparms, targs,
9967 /* Fallback to the special case allowed in
9970 If P is a class, and P has the form
9971 template-id, then A can be a derived class of
9972 the deduced A. Likewise, if P is a pointer to
9973 a class of the form template-id, A can be a
9974 pointer to a derived class pointed to by the
9976 t = get_template_base (tparms, targs,
9979 if (! t || t == error_mark_node)
9983 else if (CLASSTYPE_TEMPLATE_INFO (arg)
9984 && (CLASSTYPE_TI_TEMPLATE (parm)
9985 == CLASSTYPE_TI_TEMPLATE (arg)))
9986 /* Perhaps PARM is something like S<U> and ARG is S<int>.
9987 Then, we should unify `int' and `U'. */
9990 /* There's no chance of unification succeeding. */
9993 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
9994 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
9996 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10001 case FUNCTION_TYPE:
10002 if (TREE_CODE (arg) != TREE_CODE (parm))
10005 if (unify (tparms, targs, TREE_TYPE (parm),
10006 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10008 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10009 TYPE_ARG_TYPES (arg), 1,
10010 DEDUCE_EXACT, 0, -1);
10013 if (TREE_CODE (arg) != OFFSET_TYPE)
10015 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10016 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10018 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10022 if (DECL_TEMPLATE_PARM_P (parm))
10023 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10024 if (arg != decl_constant_value (parm))
10029 case TEMPLATE_DECL:
10030 /* Matched cases are handled by the ARG == PARM test above. */
10034 if (tree_int_cst_equal (TREE_OPERAND (parm, 1), integer_one_node)
10035 && (strict_in & UNIFY_ALLOW_MAX_CORRECTION))
10037 /* We handle this case specially, since it comes up with
10038 arrays. In particular, something like:
10040 template <int N> void f(int (&x)[N]);
10042 Here, we are trying to unify the range type, which
10043 looks like [0 ... (N - 1)]. */
10045 t1 = TREE_OPERAND (parm, 0);
10046 t2 = TREE_OPERAND (parm, 1);
10048 t = fold (build (PLUS_EXPR, integer_type_node, arg, t2));
10050 return unify (tparms, targs, t1, t, strict);
10052 /* Else fall through. */
10055 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (parm))))
10058 /* We're looking at an expression. This can happen with
10062 void foo(S<I>, S<I + 2>);
10064 This is a "nondeduced context":
10068 The nondeduced contexts are:
10070 --A type that is a template-id in which one or more of
10071 the template-arguments is an expression that references
10072 a template-parameter.
10074 In these cases, we assume deduction succeeded, but don't
10075 actually infer any unifications. */
10077 if (!uses_template_parms (parm)
10078 && !template_args_equal (parm, arg))
10084 sorry ("use of `%s' in template type unification",
10085 tree_code_name [(int) TREE_CODE (parm)]);
10091 /* Called if RESULT is explicitly instantiated, or is a member of an
10092 explicitly instantiated class, or if using -frepo and the
10093 instantiation of RESULT has been assigned to this file. */
10096 mark_decl_instantiated (tree result, int extern_p)
10098 /* We used to set this unconditionally; we moved that to
10099 do_decl_instantiation so it wouldn't get set on members of
10100 explicit class template instantiations. But we still need to set
10101 it here for the 'extern template' case in order to suppress
10102 implicit instantiations. */
10104 SET_DECL_EXPLICIT_INSTANTIATION (result);
10106 /* If this entity has already been written out, it's too late to
10107 make any modifications. */
10108 if (TREE_ASM_WRITTEN (result))
10111 if (TREE_CODE (result) != FUNCTION_DECL)
10112 /* The TREE_PUBLIC flag for function declarations will have been
10113 set correctly by tsubst. */
10114 TREE_PUBLIC (result) = 1;
10116 /* This might have been set by an earlier implicit instantiation. */
10117 DECL_COMDAT (result) = 0;
10121 DECL_INTERFACE_KNOWN (result) = 1;
10122 DECL_NOT_REALLY_EXTERN (result) = 1;
10124 /* Always make artificials weak. */
10125 if (DECL_ARTIFICIAL (result) && flag_weak)
10126 comdat_linkage (result);
10127 /* For WIN32 we also want to put explicit instantiations in
10128 linkonce sections. */
10129 else if (TREE_PUBLIC (result))
10130 maybe_make_one_only (result);
10133 if (TREE_CODE (result) == FUNCTION_DECL)
10137 /* Given two function templates PAT1 and PAT2, return:
10139 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
10141 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10142 -1 if PAT2 is more specialized than PAT1.
10143 0 if neither is more specialized.
10145 LEN is passed through to fn_type_unification. */
10148 more_specialized (tree pat1, tree pat2, int deduce, int len)
10153 /* If template argument deduction succeeds, we substitute the
10154 resulting arguments into non-deduced contexts. While doing that,
10155 we must be aware that we may encounter dependent types. */
10156 ++processing_template_decl;
10157 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
10158 NULL_TREE, 0, deduce, len);
10162 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
10163 NULL_TREE, 0, deduce, len);
10166 --processing_template_decl;
10171 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10173 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10174 -1 if PAT2 is more specialized than PAT1.
10175 0 if neither is more specialized.
10177 FULL_ARGS is the full set of template arguments that triggers this
10178 partial ordering. */
10181 more_specialized_class (tree pat1, tree pat2, tree full_args)
10186 /* Just like what happens for functions, if we are ordering between
10187 different class template specializations, we may encounter dependent
10188 types in the arguments, and we need our dependency check functions
10189 to behave correctly. */
10190 ++processing_template_decl;
10191 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10192 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10196 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10197 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10200 --processing_template_decl;
10205 /* Return the template arguments that will produce the function signature
10206 DECL from the function template FN, with the explicit template
10207 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
10208 also match. Return NULL_TREE if no satisfactory arguments could be
10209 found. DEDUCE and LEN are passed through to fn_type_unification. */
10212 get_bindings_real (tree fn,
10214 tree explicit_args,
10219 int ntparms = DECL_NTPARMS (fn);
10220 tree targs = make_tree_vec (ntparms);
10222 tree decl_arg_types;
10225 /* Substitute the explicit template arguments into the type of DECL.
10226 The call to fn_type_unification will handle substitution into the
10228 decl_type = TREE_TYPE (decl);
10229 if (explicit_args && uses_template_parms (decl_type))
10232 tree converted_args;
10234 if (DECL_TEMPLATE_INFO (decl))
10235 tmpl = DECL_TI_TEMPLATE (decl);
10237 /* We can get here for some invalid specializations. */
10241 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10242 explicit_args, NULL_TREE,
10243 tf_none, /*require_all_arguments=*/0));
10244 if (converted_args == error_mark_node)
10247 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10248 if (decl_type == error_mark_node)
10252 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10253 /* Never do unification on the 'this' parameter. */
10254 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10255 decl_arg_types = TREE_CHAIN (decl_arg_types);
10257 i = fn_type_unification (fn, explicit_args, targs,
10259 (check_rettype || DECL_CONV_FN_P (fn)
10260 ? TREE_TYPE (decl_type) : NULL_TREE),
10269 /* For most uses, we want to check the return type. */
10272 get_bindings (tree fn, tree decl, tree explicit_args)
10274 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10277 /* But for resolve_overloaded_unification, we only care about the parameter
10281 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10283 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10286 /* Return the innermost template arguments that, when applied to a
10287 template specialization whose innermost template parameters are
10288 TPARMS, and whose specialization arguments are PARMS, yield the
10291 For example, suppose we have:
10293 template <class T, class U> struct S {};
10294 template <class T> struct S<T*, int> {};
10296 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10297 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10298 int}. The resulting vector will be {double}, indicating that `T'
10299 is bound to `double'. */
10302 get_class_bindings (tree tparms, tree parms, tree args)
10304 int i, ntparms = TREE_VEC_LENGTH (tparms);
10305 tree vec = make_tree_vec (ntparms);
10307 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10311 for (i = 0; i < ntparms; ++i)
10312 if (! TREE_VEC_ELT (vec, i))
10315 if (verify_class_unification (vec, parms, args))
10321 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10322 Pick the most specialized template, and return the corresponding
10323 instantiation, or if there is no corresponding instantiation, the
10324 template itself. If there is no most specialized template,
10325 error_mark_node is returned. If there are no templates at all,
10326 NULL_TREE is returned. */
10329 most_specialized_instantiation (tree instantiations)
10334 if (!instantiations)
10337 champ = instantiations;
10338 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10340 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10348 fn = TREE_CHAIN (fn);
10350 return error_mark_node;
10356 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10358 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10361 return error_mark_node;
10364 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10367 /* Return the most specialized of the list of templates in FNS that can
10368 produce an instantiation matching DECL, given the explicit template
10369 arguments EXPLICIT_ARGS. */
10372 most_specialized (tree fns, tree decl, tree explicit_args)
10374 tree candidates = NULL_TREE;
10377 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10379 tree candidate = TREE_VALUE (fn);
10381 args = get_bindings (candidate, decl, explicit_args);
10383 candidates = tree_cons (NULL_TREE, candidate, candidates);
10386 return most_specialized_instantiation (candidates);
10389 /* If DECL is a specialization of some template, return the most
10390 general such template. Otherwise, returns NULL_TREE.
10392 For example, given:
10394 template <class T> struct S { template <class U> void f(U); };
10396 if TMPL is `template <class U> void S<int>::f(U)' this will return
10397 the full template. This function will not trace past partial
10398 specializations, however. For example, given in addition:
10400 template <class T> struct S<T*> { template <class U> void f(U); };
10402 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10403 `template <class T> template <class U> S<T*>::f(U)'. */
10406 most_general_template (tree decl)
10408 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10409 an immediate specialization. */
10410 if (TREE_CODE (decl) == FUNCTION_DECL)
10412 if (DECL_TEMPLATE_INFO (decl)) {
10413 decl = DECL_TI_TEMPLATE (decl);
10415 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10416 template friend. */
10417 if (TREE_CODE (decl) != TEMPLATE_DECL)
10423 /* Look for more and more general templates. */
10424 while (DECL_TEMPLATE_INFO (decl))
10426 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10427 (See cp-tree.h for details.) */
10428 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10431 if (CLASS_TYPE_P (TREE_TYPE (decl))
10432 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10435 /* Stop if we run into an explicitly specialized class template. */
10436 if (!DECL_NAMESPACE_SCOPE_P (decl)
10437 && DECL_CONTEXT (decl)
10438 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10441 decl = DECL_TI_TEMPLATE (decl);
10447 /* Return the most specialized of the class template specializations
10448 of TMPL which can produce an instantiation matching ARGS, or
10449 error_mark_node if the choice is ambiguous. */
10452 most_specialized_class (tree tmpl, tree args)
10454 tree list = NULL_TREE;
10459 tmpl = most_general_template (tmpl);
10460 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10463 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10466 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10467 TREE_TYPE (list) = TREE_TYPE (t);
10476 t = TREE_CHAIN (t);
10477 for (; t; t = TREE_CHAIN (t))
10479 fate = more_specialized_class (champ, t, args);
10486 t = TREE_CHAIN (t);
10488 return error_mark_node;
10494 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10496 fate = more_specialized_class (champ, t, args);
10498 return error_mark_node;
10504 /* Explicitly instantiate DECL. */
10507 do_decl_instantiation (tree decl, tree storage)
10509 tree result = NULL_TREE;
10513 /* An error occurred, for which grokdeclarator has already issued
10514 an appropriate message. */
10516 else if (! DECL_LANG_SPECIFIC (decl))
10518 error ("explicit instantiation of non-template `%#D'", decl);
10521 else if (TREE_CODE (decl) == VAR_DECL)
10523 /* There is an asymmetry here in the way VAR_DECLs and
10524 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10525 the latter, the DECL we get back will be marked as a
10526 template instantiation, and the appropriate
10527 DECL_TEMPLATE_INFO will be set up. This does not happen for
10528 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10529 should handle VAR_DECLs as it currently handles
10531 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10532 if (!result || TREE_CODE (result) != VAR_DECL)
10534 error ("no matching template for `%D' found", decl);
10538 else if (TREE_CODE (decl) != FUNCTION_DECL)
10540 error ("explicit instantiation of `%#D'", decl);
10546 /* Check for various error cases. Note that if the explicit
10547 instantiation is valid the RESULT will currently be marked as an
10548 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10549 until we get here. */
10551 if (DECL_TEMPLATE_SPECIALIZATION (result))
10553 /* DR 259 [temp.spec].
10555 Both an explicit instantiation and a declaration of an explicit
10556 specialization shall not appear in a program unless the explicit
10557 instantiation follows a declaration of the explicit specialization.
10559 For a given set of template parameters, if an explicit
10560 instantiation of a template appears after a declaration of an
10561 explicit specialization for that template, the explicit
10562 instantiation has no effect. */
10565 else if (DECL_EXPLICIT_INSTANTIATION (result))
10569 No program shall explicitly instantiate any template more
10572 We check DECL_INTERFACE_KNOWN so as not to complain when the first
10573 instantiation was `extern' and the second is not, and EXTERN_P for
10574 the opposite case. If -frepo, chances are we already got marked
10575 as an explicit instantiation because of the repo file. */
10576 if (DECL_INTERFACE_KNOWN (result) && !extern_p && !flag_use_repository)
10577 pedwarn ("duplicate explicit instantiation of `%#D'", result);
10579 /* If we've already instantiated the template, just return now. */
10580 if (DECL_INTERFACE_KNOWN (result))
10583 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10585 error ("no matching template for `%D' found", result);
10588 else if (!DECL_TEMPLATE_INFO (result))
10590 pedwarn ("explicit instantiation of non-template `%#D'", result);
10594 if (storage == NULL_TREE)
10596 else if (storage == ridpointers[(int) RID_EXTERN])
10598 if (pedantic && !in_system_header)
10599 pedwarn ("ISO C++ forbids the use of `extern' on explicit instantiations");
10603 error ("storage class `%D' applied to template instantiation",
10606 SET_DECL_EXPLICIT_INSTANTIATION (result);
10607 mark_decl_instantiated (result, extern_p);
10608 repo_template_instantiated (result, extern_p);
10610 instantiate_decl (result, /*defer_ok=*/1);
10614 mark_class_instantiated (tree t, int extern_p)
10616 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10617 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10618 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10619 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10622 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10623 rest_of_type_compilation (t, 1);
10627 /* Called from do_type_instantiation through binding_table_foreach to
10628 do recursive instantiation for the type bound in ENTRY. */
10630 bt_instantiate_type_proc (binding_entry entry, void *data)
10632 tree storage = *(tree *) data;
10634 if (IS_AGGR_TYPE (entry->type)
10635 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10636 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10639 /* Perform an explicit instantiation of template class T. STORAGE, if
10640 non-null, is the RID for extern, inline or static. COMPLAIN is
10641 nonzero if this is called from the parser, zero if called recursively,
10642 since the standard is unclear (as detailed below). */
10645 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10651 if (TREE_CODE (t) == TYPE_DECL)
10654 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10656 error ("explicit instantiation of non-template type `%T'", t);
10662 if (!COMPLETE_TYPE_P (t))
10664 if (complain & tf_error)
10665 error ("explicit instantiation of `%#T' before definition of template",
10670 if (storage != NULL_TREE)
10672 if (pedantic && !in_system_header)
10673 pedwarn("ISO C++ forbids the use of `%s' on explicit instantiations",
10674 IDENTIFIER_POINTER (storage));
10676 if (storage == ridpointers[(int) RID_INLINE])
10678 else if (storage == ridpointers[(int) RID_EXTERN])
10680 else if (storage == ridpointers[(int) RID_STATIC])
10684 error ("storage class `%D' applied to template instantiation",
10690 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10692 /* DR 259 [temp.spec].
10694 Both an explicit instantiation and a declaration of an explicit
10695 specialization shall not appear in a program unless the explicit
10696 instantiation follows a declaration of the explicit specialization.
10698 For a given set of template parameters, if an explicit
10699 instantiation of a template appears after a declaration of an
10700 explicit specialization for that template, the explicit
10701 instantiation has no effect. */
10704 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10708 No program shall explicitly instantiate any template more
10711 If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation
10712 was `extern'. If EXTERN_P then the second is. If -frepo, chances
10713 are we already got marked as an explicit instantiation because of the
10714 repo file. All these cases are OK. */
10715 if (!CLASSTYPE_INTERFACE_ONLY (t) && !extern_p && !flag_use_repository
10716 && (complain & tf_error))
10717 pedwarn ("duplicate explicit instantiation of `%#T'", t);
10719 /* If we've already instantiated the template, just return now. */
10720 if (!CLASSTYPE_INTERFACE_ONLY (t))
10724 mark_class_instantiated (t, extern_p);
10725 repo_template_instantiated (t, extern_p);
10733 /* In contrast to implicit instantiation, where only the
10734 declarations, and not the definitions, of members are
10735 instantiated, we have here:
10739 The explicit instantiation of a class template specialization
10740 implies the instantiation of all of its members not
10741 previously explicitly specialized in the translation unit
10742 containing the explicit instantiation.
10744 Of course, we can't instantiate member template classes, since
10745 we don't have any arguments for them. Note that the standard
10746 is unclear on whether the instantiation of the members are
10747 *explicit* instantiations or not. We choose to be generous,
10748 and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow
10749 the explicit instantiation of a class where some of the members
10750 have no definition in the current translation unit. */
10753 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
10754 if (TREE_CODE (tmp) == FUNCTION_DECL
10755 && DECL_TEMPLATE_INSTANTIATION (tmp))
10757 mark_decl_instantiated (tmp, extern_p);
10758 repo_template_instantiated (tmp, extern_p);
10760 instantiate_decl (tmp, /*defer_ok=*/1);
10763 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
10764 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
10766 mark_decl_instantiated (tmp, extern_p);
10767 repo_template_instantiated (tmp, extern_p);
10769 instantiate_decl (tmp, /*defer_ok=*/1);
10772 if (CLASSTYPE_NESTED_UTDS (t))
10773 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
10774 bt_instantiate_type_proc, &storage);
10778 /* Given a function DECL, which is a specialization of TMPL, modify
10779 DECL to be a re-instantiation of TMPL with the same template
10780 arguments. TMPL should be the template into which tsubst'ing
10781 should occur for DECL, not the most general template.
10783 One reason for doing this is a scenario like this:
10786 void f(const T&, int i);
10788 void g() { f(3, 7); }
10791 void f(const T& t, const int i) { }
10793 Note that when the template is first instantiated, with
10794 instantiate_template, the resulting DECL will have no name for the
10795 first parameter, and the wrong type for the second. So, when we go
10796 to instantiate the DECL, we regenerate it. */
10799 regenerate_decl_from_template (tree decl, tree tmpl)
10801 /* The most general version of TMPL. */
10803 /* The arguments used to instantiate DECL, from the most general
10810 args = DECL_TI_ARGS (decl);
10811 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
10813 /* Unregister the specialization so that when we tsubst we will not
10814 just return DECL. We don't have to unregister DECL from TMPL
10815 because if would only be registered there if it were a partial
10816 instantiation of a specialization, which it isn't: it's a full
10818 gen_tmpl = most_general_template (tmpl);
10819 unregistered = reregister_specialization (decl, gen_tmpl,
10820 /*new_spec=*/NULL_TREE);
10822 /* If the DECL was not unregistered then something peculiar is
10823 happening: we created a specialization but did not call
10824 register_specialization for it. */
10825 my_friendly_assert (unregistered, 0);
10827 /* Make sure that we can see identifiers, and compute access
10829 push_access_scope (decl);
10831 /* Do the substitution to get the new declaration. */
10832 new_decl = tsubst (code_pattern, args, tf_error, NULL_TREE);
10834 if (TREE_CODE (decl) == VAR_DECL)
10836 /* Set up DECL_INITIAL, since tsubst doesn't. */
10837 if (!DECL_INITIALIZED_IN_CLASS_P (decl))
10838 DECL_INITIAL (new_decl) =
10839 tsubst_expr (DECL_INITIAL (code_pattern), args,
10840 tf_error, DECL_TI_TEMPLATE (decl));
10842 else if (TREE_CODE (decl) == FUNCTION_DECL)
10844 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
10846 DECL_INITIAL (new_decl) = error_mark_node;
10847 /* And don't complain about a duplicate definition. */
10848 DECL_INITIAL (decl) = NULL_TREE;
10851 pop_access_scope (decl);
10853 /* The immediate parent of the new template is still whatever it was
10854 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
10855 general template. We also reset the DECL_ASSEMBLER_NAME since
10856 tsubst always calculates the name as if the function in question
10857 were really a template instance, and sometimes, with friend
10858 functions, this is not so. See tsubst_friend_function for
10860 DECL_TI_TEMPLATE (new_decl) = DECL_TI_TEMPLATE (decl);
10861 COPY_DECL_ASSEMBLER_NAME (decl, new_decl);
10862 COPY_DECL_RTL (decl, new_decl);
10863 DECL_USE_TEMPLATE (new_decl) = DECL_USE_TEMPLATE (decl);
10865 /* Call duplicate decls to merge the old and new declarations. */
10866 duplicate_decls (new_decl, decl);
10868 /* Now, re-register the specialization. */
10869 register_specialization (decl, gen_tmpl, args);
10872 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
10873 substituted to get DECL. */
10876 template_for_substitution (tree decl)
10878 tree tmpl = DECL_TI_TEMPLATE (decl);
10880 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
10881 for the instantiation. This is not always the most general
10882 template. Consider, for example:
10885 struct S { template <class U> void f();
10886 template <> void f<int>(); };
10888 and an instantiation of S<double>::f<int>. We want TD to be the
10889 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
10890 while (/* An instantiation cannot have a definition, so we need a
10891 more general template. */
10892 DECL_TEMPLATE_INSTANTIATION (tmpl)
10893 /* We must also deal with friend templates. Given:
10895 template <class T> struct S {
10896 template <class U> friend void f() {};
10899 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
10900 so far as the language is concerned, but that's still
10901 where we get the pattern for the instantiation from. On
10902 other hand, if the definition comes outside the class, say:
10904 template <class T> struct S {
10905 template <class U> friend void f();
10907 template <class U> friend void f() {}
10909 we don't need to look any further. That's what the check for
10910 DECL_INITIAL is for. */
10911 || (TREE_CODE (decl) == FUNCTION_DECL
10912 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
10913 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
10915 /* The present template, TD, should not be a definition. If it
10916 were a definition, we should be using it! Note that we
10917 cannot restructure the loop to just keep going until we find
10918 a template with a definition, since that might go too far if
10919 a specialization was declared, but not defined. */
10920 my_friendly_assert (!(TREE_CODE (decl) == VAR_DECL
10921 && !DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl))),
10924 /* Fetch the more general template. */
10925 tmpl = DECL_TI_TEMPLATE (tmpl);
10931 /* Produce the definition of D, a _DECL generated from a template. If
10932 DEFER_OK is nonzero, then we don't have to actually do the
10933 instantiation now; we just have to do it sometime. */
10936 instantiate_decl (tree d, int defer_ok)
10938 tree tmpl = DECL_TI_TEMPLATE (d);
10945 int pattern_defined;
10947 location_t saved_loc = input_location;
10949 /* This function should only be used to instantiate templates for
10950 functions and static member variables. */
10951 my_friendly_assert (TREE_CODE (d) == FUNCTION_DECL
10952 || TREE_CODE (d) == VAR_DECL, 0);
10954 /* Variables are never deferred; if instantiation is required, they
10955 are instantiated right away. That allows for better code in the
10956 case that an expression refers to the value of the variable --
10957 if the variable has a constant value the referring expression can
10958 take advantage of that fact. */
10959 if (TREE_CODE (d) == VAR_DECL)
10962 /* Don't instantiate cloned functions. Instead, instantiate the
10963 functions they cloned. */
10964 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
10965 d = DECL_CLONED_FUNCTION (d);
10967 if (DECL_TEMPLATE_INSTANTIATED (d))
10968 /* D has already been instantiated. It might seem reasonable to
10969 check whether or not D is an explicit instantiation, and, if so,
10970 stop here. But when an explicit instantiation is deferred
10971 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
10972 is set, even though we still need to do the instantiation. */
10975 /* If we already have a specialization of this declaration, then
10976 there's no reason to instantiate it. Note that
10977 retrieve_specialization gives us both instantiations and
10978 specializations, so we must explicitly check
10979 DECL_TEMPLATE_SPECIALIZATION. */
10980 gen_tmpl = most_general_template (tmpl);
10981 gen_args = DECL_TI_ARGS (d);
10982 spec = retrieve_specialization (gen_tmpl, gen_args);
10983 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
10986 /* This needs to happen before any tsubsting. */
10987 if (! push_tinst_level (d))
10990 timevar_push (TV_PARSE);
10992 /* We may be in the middle of deferred access check. Disable it now. */
10993 push_deferring_access_checks (dk_no_deferred);
10995 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
10996 for the instantiation. */
10997 td = template_for_substitution (d);
10998 code_pattern = DECL_TEMPLATE_RESULT (td);
11000 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11001 || DECL_TEMPLATE_SPECIALIZATION (td))
11002 /* In the case of a friend template whose definition is provided
11003 outside the class, we may have too many arguments. Drop the
11004 ones we don't need. The same is true for specializations. */
11005 args = get_innermost_template_args
11006 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11010 if (TREE_CODE (d) == FUNCTION_DECL)
11011 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11013 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11015 input_location = DECL_SOURCE_LOCATION (d);
11017 if (pattern_defined)
11019 /* Let the repository code that this template definition is
11022 The repository doesn't need to know about cloned functions
11023 because they never actually show up in the object file. It
11024 does need to know about the clones; those are the symbols
11025 that the linker will be emitting error messages about. */
11026 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (d)
11027 || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (d))
11031 for (t = TREE_CHAIN (d);
11032 t && DECL_CLONED_FUNCTION_P (t);
11033 t = TREE_CHAIN (t))
11034 repo_template_used (t);
11037 repo_template_used (d);
11040 import_export_decl (d);
11045 /* Recheck the substitutions to obtain any warning messages
11046 about ignoring cv qualifiers. */
11047 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11048 tree type = TREE_TYPE (gen);
11050 /* Make sure that we can see identifiers, and compute access
11051 correctly. D is already the target FUNCTION_DECL with the
11053 push_access_scope (d);
11055 if (TREE_CODE (gen) == FUNCTION_DECL)
11057 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11058 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11059 tf_error | tf_warning, d);
11060 /* Don't simply tsubst the function type, as that will give
11061 duplicate warnings about poor parameter qualifications.
11062 The function arguments are the same as the decl_arguments
11063 without the top level cv qualifiers. */
11064 type = TREE_TYPE (type);
11066 tsubst (type, gen_args, tf_error | tf_warning, d);
11068 pop_access_scope (d);
11071 if (TREE_CODE (d) == VAR_DECL && DECL_INITIALIZED_IN_CLASS_P (d)
11072 && DECL_INITIAL (d) == NULL_TREE)
11073 /* We should have set up DECL_INITIAL in instantiate_class_template. */
11075 /* Reject all external templates except inline functions. */
11076 else if (DECL_INTERFACE_KNOWN (d)
11077 && ! DECL_NOT_REALLY_EXTERN (d)
11078 && ! (TREE_CODE (d) == FUNCTION_DECL
11079 && DECL_INLINE (d)))
11081 /* Defer all other templates, unless we have been explicitly
11082 forbidden from doing so. We restore the source position here
11083 because it's used by add_pending_template. */
11084 else if (! pattern_defined || defer_ok)
11086 input_location = saved_loc;
11088 if (at_eof && !pattern_defined
11089 && DECL_EXPLICIT_INSTANTIATION (d))
11092 The definition of a non-exported function template, a
11093 non-exported member function template, or a non-exported
11094 member function or static data member of a class template
11095 shall be present in every translation unit in which it is
11096 explicitly instantiated. */
11098 ("explicit instantiation of `%D' but no definition available", d);
11100 add_pending_template (d);
11104 need_push = !global_bindings_p ();
11106 push_to_top_level ();
11108 /* Mark D as instantiated so that recursive calls to
11109 instantiate_decl do not try to instantiate it again. */
11110 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11112 /* Regenerate the declaration in case the template has been modified
11113 by a subsequent redeclaration. */
11114 regenerate_decl_from_template (d, td);
11116 /* We already set the file and line above. Reset them now in case
11117 they changed as a result of calling
11118 regenerate_decl_from_template. */
11119 input_location = DECL_SOURCE_LOCATION (d);
11121 if (TREE_CODE (d) == VAR_DECL)
11123 /* Clear out DECL_RTL; whatever was there before may not be right
11124 since we've reset the type of the declaration. */
11125 SET_DECL_RTL (d, NULL_RTX);
11127 DECL_IN_AGGR_P (d) = 0;
11128 import_export_decl (d);
11129 DECL_EXTERNAL (d) = ! DECL_NOT_REALLY_EXTERN (d);
11131 if (DECL_EXTERNAL (d))
11133 /* The fact that this code is executing indicates that:
11135 (1) D is a template static data member, for which a
11136 definition is available.
11138 (2) An implicit or explicit instantiation has occurred.
11140 (3) We are not going to emit a definition of the static
11141 data member at this time.
11143 This situation is peculiar, but it occurs on platforms
11144 without weak symbols when performing an implicit
11145 instantiation. There, we cannot implicitly instantiate a
11146 defined static data member in more than one translation
11147 unit, so import_export_decl marks the declaration as
11148 external; we must rely on explicit instantiation.
11150 Reset instantiated marker to make sure that later
11151 explicit instantiation will be processed. */
11152 DECL_TEMPLATE_INSTANTIATED (d) = 0;
11156 /* This is done in analogous to `start_decl'. It is
11157 required for correct access checking. */
11158 push_nested_class (DECL_CONTEXT (d));
11160 (!DECL_INITIALIZED_IN_CLASS_P (d)
11161 ? DECL_INITIAL (d) : NULL_TREE),
11163 /* Normally, pop_nested_class is called by cp_finish_decl
11164 above. But when instantiate_decl is triggered during
11165 instantiate_class_template processing, its DECL_CONTEXT
11166 is still not completed yet, and pop_nested_class isn't
11168 if (!COMPLETE_TYPE_P (DECL_CONTEXT (d)))
11169 pop_nested_class ();
11172 else if (TREE_CODE (d) == FUNCTION_DECL)
11174 htab_t saved_local_specializations;
11179 /* Mark D as instantiated so that recursive calls to
11180 instantiate_decl do not try to instantiate it again. */
11181 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11183 /* Save away the current list, in case we are instantiating one
11184 template from within the body of another. */
11185 saved_local_specializations = local_specializations;
11187 /* Set up the list of local specializations. */
11188 local_specializations = htab_create (37,
11189 hash_local_specialization,
11190 eq_local_specializations,
11193 /* Set up context. */
11194 import_export_decl (d);
11195 start_function (NULL_TREE, d, NULL_TREE, SF_PRE_PARSED);
11197 /* Create substitution entries for the parameters. */
11198 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11199 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11200 spec_parm = DECL_ARGUMENTS (d);
11201 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11203 register_local_specialization (spec_parm, tmpl_parm);
11204 spec_parm = skip_artificial_parms_for (d, spec_parm);
11205 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11209 register_local_specialization (spec_parm, tmpl_parm);
11210 tmpl_parm = TREE_CHAIN (tmpl_parm);
11211 spec_parm = TREE_CHAIN (spec_parm);
11213 my_friendly_assert (!spec_parm, 20020813);
11215 /* Substitute into the body of the function. */
11216 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11217 tf_error | tf_warning, tmpl);
11219 /* We don't need the local specializations any more. */
11220 htab_delete (local_specializations);
11221 local_specializations = saved_local_specializations;
11223 /* Finish the function. */
11224 d = finish_function (0);
11225 expand_or_defer_fn (d);
11228 /* We're not deferring instantiation any more. */
11229 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11232 pop_from_top_level ();
11235 input_location = saved_loc;
11236 pop_deferring_access_checks ();
11237 pop_tinst_level ();
11239 timevar_pop (TV_PARSE);
11244 /* Run through the list of templates that we wish we could
11245 instantiate, and instantiate any we can. */
11248 instantiate_pending_templates (void)
11251 tree last = NULL_TREE;
11252 int instantiated_something = 0;
11254 location_t saved_loc = input_location;
11260 t = &pending_templates;
11263 tree instantiation = TREE_VALUE (*t);
11265 reopen_tinst_level (TREE_PURPOSE (*t));
11267 if (TYPE_P (instantiation))
11271 if (!COMPLETE_TYPE_P (instantiation))
11273 instantiate_class_template (instantiation);
11274 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11275 for (fn = TYPE_METHODS (instantiation);
11277 fn = TREE_CHAIN (fn))
11278 if (! DECL_ARTIFICIAL (fn))
11279 instantiate_decl (fn, /*defer_ok=*/0);
11280 if (COMPLETE_TYPE_P (instantiation))
11282 instantiated_something = 1;
11287 if (COMPLETE_TYPE_P (instantiation))
11288 /* If INSTANTIATION has been instantiated, then we don't
11289 need to consider it again in the future. */
11290 *t = TREE_CHAIN (*t);
11294 t = &TREE_CHAIN (*t);
11299 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11300 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11302 instantiation = instantiate_decl (instantiation,
11304 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11306 instantiated_something = 1;
11311 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11312 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11313 /* If INSTANTIATION has been instantiated, then we don't
11314 need to consider it again in the future. */
11315 *t = TREE_CHAIN (*t);
11319 t = &TREE_CHAIN (*t);
11323 current_tinst_level = NULL_TREE;
11325 last_pending_template = last;
11327 while (reconsider);
11329 input_location = saved_loc;
11330 return instantiated_something;
11333 /* Substitute ARGVEC into T, which is a list of initializers for
11334 either base class or a non-static data member. The TREE_PURPOSEs
11335 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11336 instantiate_decl. */
11339 tsubst_initializer_list (tree t, tree argvec)
11341 tree inits = NULL_TREE;
11343 for (; t; t = TREE_CHAIN (t))
11349 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11351 decl = expand_member_init (decl);
11352 if (decl && !DECL_P (decl))
11353 in_base_initializer = 1;
11355 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11359 else if (TREE_CODE (init) == TREE_LIST)
11360 for (val = init; val; val = TREE_CHAIN (val))
11361 TREE_VALUE (val) = convert_from_reference (TREE_VALUE (val));
11362 else if (init != void_type_node)
11363 init = convert_from_reference (init);
11365 in_base_initializer = 0;
11369 init = build_tree_list (decl, init);
11370 TREE_CHAIN (init) = inits;
11377 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11380 set_current_access_from_decl (tree decl)
11382 if (TREE_PRIVATE (decl))
11383 current_access_specifier = access_private_node;
11384 else if (TREE_PROTECTED (decl))
11385 current_access_specifier = access_protected_node;
11387 current_access_specifier = access_public_node;
11390 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11391 is the instantiation (which should have been created with
11392 start_enum) and ARGS are the template arguments to use. */
11395 tsubst_enum (tree tag, tree newtag, tree args)
11399 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11404 decl = TREE_VALUE (e);
11405 /* Note that in a template enum, the TREE_VALUE is the
11406 CONST_DECL, not the corresponding INTEGER_CST. */
11407 value = tsubst_expr (DECL_INITIAL (decl),
11408 args, tf_error | tf_warning,
11411 /* Give this enumeration constant the correct access. */
11412 set_current_access_from_decl (decl);
11414 /* Actually build the enumerator itself. */
11415 build_enumerator (DECL_NAME (decl), value, newtag);
11418 finish_enum (newtag);
11419 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11420 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11423 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11424 its type -- but without substituting the innermost set of template
11425 arguments. So, innermost set of template parameters will appear in
11429 get_mostly_instantiated_function_type (tree decl)
11437 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11438 targs = DECL_TI_ARGS (decl);
11439 tparms = DECL_TEMPLATE_PARMS (tmpl);
11440 parm_depth = TMPL_PARMS_DEPTH (tparms);
11442 /* There should be as many levels of arguments as there are levels
11444 my_friendly_assert (parm_depth == TMPL_ARGS_DEPTH (targs), 0);
11446 fn_type = TREE_TYPE (tmpl);
11448 if (parm_depth == 1)
11449 /* No substitution is necessary. */
11456 /* Replace the innermost level of the TARGS with NULL_TREEs to
11457 let tsubst know not to substitute for those parameters. */
11458 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11459 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11460 SET_TMPL_ARGS_LEVEL (partial_args, i,
11461 TMPL_ARGS_LEVEL (targs, i));
11462 SET_TMPL_ARGS_LEVEL (partial_args,
11463 TMPL_ARGS_DEPTH (targs),
11464 make_tree_vec (DECL_NTPARMS (tmpl)));
11466 /* Make sure that we can see identifiers, and compute access
11467 correctly. We can just use the context of DECL for the
11468 partial substitution here. It depends only on outer template
11469 parameters, regardless of whether the innermost level is
11470 specialized or not. */
11471 push_access_scope (decl);
11473 ++processing_template_decl;
11474 /* Now, do the (partial) substitution to figure out the
11475 appropriate function type. */
11476 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11477 --processing_template_decl;
11479 /* Substitute into the template parameters to obtain the real
11480 innermost set of parameters. This step is important if the
11481 innermost set of template parameters contains value
11482 parameters whose types depend on outer template parameters. */
11483 TREE_VEC_LENGTH (partial_args)--;
11484 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11486 pop_access_scope (decl);
11492 /* Return truthvalue if we're processing a template different from
11493 the last one involved in diagnostics. */
11495 problematic_instantiation_changed (void)
11497 return last_template_error_tick != tinst_level_tick;
11500 /* Remember current template involved in diagnostics. */
11502 record_last_problematic_instantiation (void)
11504 last_template_error_tick = tinst_level_tick;
11508 current_instantiation (void)
11510 return current_tinst_level;
11513 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11514 type. Return zero for ok, nonzero for disallowed. Issue error and
11515 warning messages under control of COMPLAIN. */
11518 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11520 if (INTEGRAL_TYPE_P (type))
11522 else if (POINTER_TYPE_P (type))
11524 else if (TYPE_PTR_TO_MEMBER_P (type))
11526 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11528 else if (TREE_CODE (type) == TYPENAME_TYPE)
11531 if (complain & tf_error)
11532 error ("`%#T' is not a valid type for a template constant parameter",
11537 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11538 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11541 dependent_type_p_r (tree type)
11547 A type is dependent if it is:
11549 -- a template parameter. Template template parameters are
11550 types for us (since TYPE_P holds true for them) so we
11551 handle them here. */
11552 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11553 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11555 /* -- a qualified-id with a nested-name-specifier which contains a
11556 class-name that names a dependent type or whose unqualified-id
11557 names a dependent type. */
11558 if (TREE_CODE (type) == TYPENAME_TYPE)
11560 /* -- a cv-qualified type where the cv-unqualified type is
11562 type = TYPE_MAIN_VARIANT (type);
11563 /* -- a compound type constructed from any dependent type. */
11564 if (TYPE_PTR_TO_MEMBER_P (type))
11565 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11566 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11568 else if (TREE_CODE (type) == POINTER_TYPE
11569 || TREE_CODE (type) == REFERENCE_TYPE)
11570 return dependent_type_p (TREE_TYPE (type));
11571 else if (TREE_CODE (type) == FUNCTION_TYPE
11572 || TREE_CODE (type) == METHOD_TYPE)
11576 if (dependent_type_p (TREE_TYPE (type)))
11578 for (arg_type = TYPE_ARG_TYPES (type);
11580 arg_type = TREE_CHAIN (arg_type))
11581 if (dependent_type_p (TREE_VALUE (arg_type)))
11585 /* -- an array type constructed from any dependent type or whose
11586 size is specified by a constant expression that is
11587 value-dependent. */
11588 if (TREE_CODE (type) == ARRAY_TYPE)
11590 if (TYPE_DOMAIN (type)
11591 && ((value_dependent_expression_p
11592 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11593 || (type_dependent_expression_p
11594 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11596 return dependent_type_p (TREE_TYPE (type));
11599 /* -- a template-id in which either the template name is a template
11601 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11603 /* ... or any of the template arguments is a dependent type or
11604 an expression that is type-dependent or value-dependent. */
11605 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11606 && (any_dependent_template_arguments_p
11607 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11610 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11611 expression is not type-dependent, then it should already been
11613 if (TREE_CODE (type) == TYPEOF_TYPE)
11616 /* The standard does not specifically mention types that are local
11617 to template functions or local classes, but they should be
11618 considered dependent too. For example:
11620 template <int I> void f() {
11625 The size of `E' cannot be known until the value of `I' has been
11626 determined. Therefore, `E' must be considered dependent. */
11627 scope = TYPE_CONTEXT (type);
11628 if (scope && TYPE_P (scope))
11629 return dependent_type_p (scope);
11630 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11631 return type_dependent_expression_p (scope);
11633 /* Other types are non-dependent. */
11637 /* Returns TRUE if TYPE is dependent, in the sense of
11638 [temp.dep.type]. */
11641 dependent_type_p (tree type)
11643 /* If there are no template parameters in scope, then there can't be
11644 any dependent types. */
11645 if (!processing_template_decl)
11648 /* If the type is NULL, we have not computed a type for the entity
11649 in question; in that case, the type is dependent. */
11653 /* Erroneous types can be considered non-dependent. */
11654 if (type == error_mark_node)
11657 /* If we have not already computed the appropriate value for TYPE,
11659 if (!TYPE_DEPENDENT_P_VALID (type))
11661 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11662 TYPE_DEPENDENT_P_VALID (type) = 1;
11665 return TYPE_DEPENDENT_P (type);
11668 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11671 dependent_scope_ref_p (tree expression, bool criterion (tree))
11676 my_friendly_assert (TREE_CODE (expression) == SCOPE_REF, 20030714);
11678 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11681 scope = TREE_OPERAND (expression, 0);
11682 name = TREE_OPERAND (expression, 1);
11686 An id-expression is type-dependent if it contains a
11687 nested-name-specifier that contains a class-name that names a
11689 /* The suggested resolution to Core Issue 2 implies that if the
11690 qualifying type is the current class, then we must peek
11693 && currently_open_class (scope)
11694 && !criterion (name))
11696 if (dependent_type_p (scope))
11702 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11703 [temp.dep.constexpr] */
11706 value_dependent_expression_p (tree expression)
11708 if (!processing_template_decl)
11711 /* A name declared with a dependent type. */
11712 if (TREE_CODE (expression) == IDENTIFIER_NODE
11713 || (DECL_P (expression)
11714 && type_dependent_expression_p (expression)))
11716 /* A non-type template parameter. */
11717 if ((TREE_CODE (expression) == CONST_DECL
11718 && DECL_TEMPLATE_PARM_P (expression))
11719 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11721 /* A constant with integral or enumeration type and is initialized
11722 with an expression that is value-dependent. */
11723 if (TREE_CODE (expression) == VAR_DECL
11724 && DECL_INITIAL (expression)
11725 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11726 && value_dependent_expression_p (DECL_INITIAL (expression)))
11728 /* These expressions are value-dependent if the type to which the
11729 cast occurs is dependent or the expression being casted is
11730 value-dependent. */
11731 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11732 || TREE_CODE (expression) == STATIC_CAST_EXPR
11733 || TREE_CODE (expression) == CONST_CAST_EXPR
11734 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11735 || TREE_CODE (expression) == CAST_EXPR)
11737 if (dependent_type_p (TREE_TYPE (expression)))
11739 /* A functional cast has a list of operands. */
11740 expression = TREE_OPERAND (expression, 0);
11741 if (TREE_CODE (expression) == TREE_LIST)
11745 if (value_dependent_expression_p (TREE_VALUE (expression)))
11747 expression = TREE_CHAIN (expression);
11749 while (expression);
11753 return value_dependent_expression_p (expression);
11755 /* A `sizeof' expression is value-dependent if the operand is
11757 if (TREE_CODE (expression) == SIZEOF_EXPR
11758 || TREE_CODE (expression) == ALIGNOF_EXPR)
11760 expression = TREE_OPERAND (expression, 0);
11761 if (TYPE_P (expression))
11762 return dependent_type_p (expression);
11763 return type_dependent_expression_p (expression);
11765 if (TREE_CODE (expression) == SCOPE_REF)
11766 return dependent_scope_ref_p (expression, value_dependent_expression_p);
11767 if (TREE_CODE (expression) == COMPONENT_REF)
11768 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
11769 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
11770 /* A constant expression is value-dependent if any subexpression is
11771 value-dependent. */
11772 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (expression))))
11774 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
11777 return (value_dependent_expression_p
11778 (TREE_OPERAND (expression, 0)));
11781 return ((value_dependent_expression_p
11782 (TREE_OPERAND (expression, 0)))
11783 || (value_dependent_expression_p
11784 (TREE_OPERAND (expression, 1))));
11788 for (i = 0; i < first_rtl_op (TREE_CODE (expression)); ++i)
11789 /* In some cases, some of the operands may be missing.
11790 (For example, in the case of PREDECREMENT_EXPR, the
11791 amount to increment by may be missing.) That doesn't
11792 make the expression dependent. */
11793 if (TREE_OPERAND (expression, i)
11794 && (value_dependent_expression_p
11795 (TREE_OPERAND (expression, i))))
11802 /* The expression is not value-dependent. */
11806 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11807 [temp.dep.expr]. */
11810 type_dependent_expression_p (tree expression)
11812 if (!processing_template_decl)
11815 if (expression == error_mark_node)
11818 /* An unresolved name is always dependent. */
11819 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11822 /* Some expression forms are never type-dependent. */
11823 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
11824 || TREE_CODE (expression) == SIZEOF_EXPR
11825 || TREE_CODE (expression) == ALIGNOF_EXPR
11826 || TREE_CODE (expression) == TYPEID_EXPR
11827 || TREE_CODE (expression) == DELETE_EXPR
11828 || TREE_CODE (expression) == VEC_DELETE_EXPR
11829 || TREE_CODE (expression) == THROW_EXPR)
11832 /* The types of these expressions depends only on the type to which
11833 the cast occurs. */
11834 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11835 || TREE_CODE (expression) == STATIC_CAST_EXPR
11836 || TREE_CODE (expression) == CONST_CAST_EXPR
11837 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11838 || TREE_CODE (expression) == CAST_EXPR)
11839 return dependent_type_p (TREE_TYPE (expression));
11841 /* The types of these expressions depends only on the type created
11842 by the expression. */
11843 if (TREE_CODE (expression) == NEW_EXPR
11844 || TREE_CODE (expression) == VEC_NEW_EXPR)
11846 /* For NEW_EXPR tree nodes created inside a template, either
11847 the object type itself or a TREE_LIST may appear as the
11849 tree type = TREE_OPERAND (expression, 1);
11850 if (TREE_CODE (type) == TREE_LIST)
11851 /* This is an array type. We need to check array dimensions
11853 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
11854 || value_dependent_expression_p
11855 (TREE_OPERAND (TREE_VALUE (type), 1));
11857 return dependent_type_p (type);
11860 if (TREE_CODE (expression) == SCOPE_REF
11861 && dependent_scope_ref_p (expression,
11862 type_dependent_expression_p))
11865 if (TREE_CODE (expression) == FUNCTION_DECL
11866 && DECL_LANG_SPECIFIC (expression)
11867 && DECL_TEMPLATE_INFO (expression)
11868 && (any_dependent_template_arguments_p
11869 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
11872 if (TREE_CODE (expression) == TEMPLATE_DECL
11873 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
11876 if (TREE_TYPE (expression) == unknown_type_node)
11878 if (TREE_CODE (expression) == ADDR_EXPR)
11879 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
11880 if (TREE_CODE (expression) == COMPONENT_REF
11881 || TREE_CODE (expression) == OFFSET_REF)
11883 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
11885 expression = TREE_OPERAND (expression, 1);
11886 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11890 if (TREE_CODE (expression) == BASELINK)
11891 expression = BASELINK_FUNCTIONS (expression);
11892 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
11894 if (any_dependent_template_arguments_p
11895 (TREE_OPERAND (expression, 1)))
11897 expression = TREE_OPERAND (expression, 0);
11899 if (TREE_CODE (expression) == OVERLOAD)
11903 if (type_dependent_expression_p (OVL_CURRENT (expression)))
11905 expression = OVL_NEXT (expression);
11912 return (dependent_type_p (TREE_TYPE (expression)));
11915 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
11916 contains a type-dependent expression. */
11919 any_type_dependent_arguments_p (tree args)
11923 tree arg = TREE_VALUE (args);
11925 if (type_dependent_expression_p (arg))
11927 args = TREE_CHAIN (args);
11932 /* Returns TRUE if the ARG (a template argument) is dependent. */
11935 dependent_template_arg_p (tree arg)
11937 if (!processing_template_decl)
11940 if (TREE_CODE (arg) == TEMPLATE_DECL
11941 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11942 return dependent_template_p (arg);
11943 else if (TYPE_P (arg))
11944 return dependent_type_p (arg);
11946 return (type_dependent_expression_p (arg)
11947 || value_dependent_expression_p (arg));
11950 /* Returns true if ARGS (a collection of template arguments) contains
11951 any dependent arguments. */
11954 any_dependent_template_arguments_p (tree args)
11962 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
11964 tree level = TMPL_ARGS_LEVEL (args, i + 1);
11965 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
11966 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
11973 /* Returns TRUE if the template TMPL is dependent. */
11976 dependent_template_p (tree tmpl)
11978 if (TREE_CODE (tmpl) == OVERLOAD)
11982 if (dependent_template_p (OVL_FUNCTION (tmpl)))
11984 tmpl = OVL_CHAIN (tmpl);
11989 /* Template template parameters are dependent. */
11990 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
11991 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
11993 /* So are qualified names that have not been looked up. */
11994 if (TREE_CODE (tmpl) == SCOPE_REF)
11996 /* So are member templates of dependent classes. */
11997 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
11998 return dependent_type_p (DECL_CONTEXT (tmpl));
12002 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12005 dependent_template_id_p (tree tmpl, tree args)
12007 return (dependent_template_p (tmpl)
12008 || any_dependent_template_arguments_p (args));
12011 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12012 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12013 can be found. Note that this function peers inside uninstantiated
12014 templates and therefore should be used only in extremely limited
12018 resolve_typename_type (tree type, bool only_current_p)
12026 my_friendly_assert (TREE_CODE (type) == TYPENAME_TYPE,
12029 scope = TYPE_CONTEXT (type);
12030 name = TYPE_IDENTIFIER (type);
12032 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12033 it first before we can figure out what NAME refers to. */
12034 if (TREE_CODE (scope) == TYPENAME_TYPE)
12035 scope = resolve_typename_type (scope, only_current_p);
12036 /* If we don't know what SCOPE refers to, then we cannot resolve the
12038 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12039 return error_mark_node;
12040 /* If the SCOPE is a template type parameter, we have no way of
12041 resolving the name. */
12042 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12044 /* If the SCOPE is not the current instantiation, there's no reason
12045 to look inside it. */
12046 if (only_current_p && !currently_open_class (scope))
12047 return error_mark_node;
12048 /* If SCOPE is a partial instantiation, it will not have a valid
12049 TYPE_FIELDS list, so use the original template. */
12050 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12051 /* Enter the SCOPE so that name lookup will be resolved as if we
12052 were in the class definition. In particular, SCOPE will no
12053 longer be considered a dependent type. */
12054 pop_p = push_scope (scope);
12055 /* Look up the declaration. */
12056 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12057 /* Obtain the set of qualifiers applied to the TYPE. */
12058 quals = cp_type_quals (type);
12059 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12060 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12062 type = error_mark_node;
12063 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12064 && TREE_CODE (decl) == TYPE_DECL)
12065 type = TREE_TYPE (decl);
12066 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12067 && DECL_CLASS_TEMPLATE_P (decl))
12071 /* Obtain the template and the arguments. */
12072 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12073 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12074 /* Instantiate the template. */
12075 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12076 /*entering_scope=*/0, tf_error | tf_user);
12079 type = error_mark_node;
12080 /* Qualify the resulting type. */
12081 if (type != error_mark_node && quals)
12082 type = cp_build_qualified_type (type, quals);
12083 /* Leave the SCOPE. */
12090 /* EXPR is an expression which is not type-dependent. Return a proxy
12091 for EXPR that can be used to compute the types of larger
12092 expressions containing EXPR. */
12095 build_non_dependent_expr (tree expr)
12097 /* Preserve null pointer constants so that the type of things like
12098 "p == 0" where "p" is a pointer can be determined. */
12099 if (null_ptr_cst_p (expr))
12101 /* Preserve OVERLOADs; the functions must be available to resolve
12103 if (TREE_CODE (expr) == OVERLOAD
12104 || TREE_CODE (expr) == FUNCTION_DECL
12105 || TREE_CODE (expr) == TEMPLATE_DECL)
12107 /* Preserve string constants; conversions from string constants to
12108 "char *" are allowed, even though normally a "const char *"
12109 cannot be used to initialize a "char *". */
12110 if (TREE_CODE (expr) == STRING_CST)
12112 /* Preserve arithmetic constants, as an optimization -- there is no
12113 reason to create a new node. */
12114 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12117 if (TREE_CODE (expr) == COND_EXPR)
12118 return build (COND_EXPR,
12120 TREE_OPERAND (expr, 0),
12121 (TREE_OPERAND (expr, 1)
12122 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12123 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12124 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12125 if (TREE_CODE (expr) == COMPOUND_EXPR
12126 && !COMPOUND_EXPR_OVERLOADED (expr))
12127 return build (COMPOUND_EXPR,
12129 TREE_OPERAND (expr, 0),
12130 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12132 /* Otherwise, build a NON_DEPENDENT_EXPR.
12134 REFERENCE_TYPEs are not stripped for expressions in templates
12135 because doing so would play havoc with mangling. Consider, for
12138 template <typename T> void f<T& g>() { g(); }
12140 In the body of "f", the expression for "g" will have
12141 REFERENCE_TYPE, even though the standard says that it should
12142 not. The reason is that we must preserve the syntactic form of
12143 the expression so that mangling (say) "f<g>" inside the body of
12144 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12146 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12149 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12150 Return a new TREE_LIST with the various arguments replaced with
12151 equivalent non-dependent expressions. */
12154 build_non_dependent_args (tree args)
12159 new_args = NULL_TREE;
12160 for (a = args; a; a = TREE_CHAIN (a))
12161 new_args = tree_cons (NULL_TREE,
12162 build_non_dependent_expr (TREE_VALUE (a)),
12164 return nreverse (new_args);
12167 #include "gt-cp-pt.h"