1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003 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);
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 int list_eq (tree, tree);
104 static tree get_class_bindings (tree, tree, tree);
105 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
106 static void tsubst_enum (tree, tree, tree);
107 static tree add_to_template_args (tree, tree);
108 static tree add_outermost_template_args (tree, tree);
109 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
110 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
111 static int type_unification_real (tree, tree, tree, tree,
112 int, unification_kind_t, int, int);
113 static void note_template_header (int);
114 static tree convert_nontype_argument (tree, tree);
115 static tree convert_template_argument (tree, tree, tree,
116 tsubst_flags_t, int, tree);
117 static tree get_bindings_overload (tree, tree, tree);
118 static int for_each_template_parm (tree, tree_fn_t, void*, htab_t);
119 static tree build_template_parm_index (int, int, int, tree, tree);
120 static int inline_needs_template_parms (tree);
121 static void push_inline_template_parms_recursive (tree, int);
122 static tree retrieve_specialization (tree, tree);
123 static tree retrieve_local_specialization (tree);
124 static tree register_specialization (tree, tree, tree);
125 static void register_local_specialization (tree, tree);
126 static tree reduce_template_parm_level (tree, tree, int);
127 static tree build_template_decl (tree, tree);
128 static int mark_template_parm (tree, void *);
129 static int template_parm_this_level_p (tree, void *);
130 static tree tsubst_friend_function (tree, tree);
131 static tree tsubst_friend_class (tree, tree);
132 static int can_complete_type_without_circularity (tree);
133 static tree get_bindings (tree, tree, tree);
134 static tree get_bindings_real (tree, tree, tree, int, int, int);
135 static int template_decl_level (tree);
136 static int check_cv_quals_for_unify (int, tree, tree);
137 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
138 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
139 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
140 static void regenerate_decl_from_template (tree, tree);
141 static tree most_specialized (tree, tree, tree);
142 static tree most_specialized_class (tree, tree);
143 static int template_class_depth_real (tree, int);
144 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
145 static tree tsubst_decl (tree, tree, tree, tsubst_flags_t);
146 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
147 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
148 static void check_specialization_scope (void);
149 static tree process_partial_specialization (tree);
150 static void set_current_access_from_decl (tree);
151 static void check_default_tmpl_args (tree, tree, int, int);
152 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
153 static tree get_template_base_recursive (tree, tree, tree, tree, tree, int);
154 static tree get_template_base (tree, tree, tree, tree);
155 static int verify_class_unification (tree, tree, tree);
156 static tree try_class_unification (tree, tree, tree, tree);
157 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
159 static tree determine_specialization (tree, tree, tree *, int);
160 static int template_args_equal (tree, tree);
161 static void tsubst_default_arguments (tree);
162 static tree for_each_template_parm_r (tree *, int *, void *);
163 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
164 static void copy_default_args_to_explicit_spec (tree);
165 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
166 static int eq_local_specializations (const void *, const void *);
167 static bool dependent_type_p_r (tree);
168 static tree tsubst (tree, tree, tsubst_flags_t, tree);
169 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
170 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
172 /* Make the current scope suitable for access checking when we are
173 processing T. T can be FUNCTION_DECL for instantiated function
174 template, or VAR_DECL for static member variable (need by
175 instantiate_decl). */
178 push_access_scope (tree t)
180 my_friendly_assert (TREE_CODE (t) == FUNCTION_DECL
181 || TREE_CODE (t) == VAR_DECL,
184 if (DECL_CLASS_SCOPE_P (t))
185 push_nested_class (DECL_CONTEXT (t));
187 push_to_top_level ();
189 if (TREE_CODE (t) == FUNCTION_DECL)
191 saved_access_scope = tree_cons
192 (NULL_TREE, current_function_decl, saved_access_scope);
193 current_function_decl = t;
197 /* Restore the scope set up by push_access_scope. T is the node we
201 pop_access_scope (tree t)
203 if (TREE_CODE (t) == FUNCTION_DECL)
205 current_function_decl = TREE_VALUE (saved_access_scope);
206 saved_access_scope = TREE_CHAIN (saved_access_scope);
209 if (DECL_CLASS_SCOPE_P (t))
212 pop_from_top_level ();
215 /* Do any processing required when DECL (a member template
216 declaration) is finished. Returns the TEMPLATE_DECL corresponding
217 to DECL, unless it is a specialization, in which case the DECL
218 itself is returned. */
221 finish_member_template_decl (tree decl)
223 if (decl == error_mark_node)
224 return error_mark_node;
226 my_friendly_assert (DECL_P (decl), 20020812);
228 if (TREE_CODE (decl) == TYPE_DECL)
232 type = TREE_TYPE (decl);
233 if (IS_AGGR_TYPE (type)
234 && CLASSTYPE_TEMPLATE_INFO (type)
235 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
237 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
238 check_member_template (tmpl);
243 else if (TREE_CODE (decl) == FIELD_DECL)
244 error ("data member `%D' cannot be a member template", decl);
245 else if (DECL_TEMPLATE_INFO (decl))
247 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
249 check_member_template (DECL_TI_TEMPLATE (decl));
250 return DECL_TI_TEMPLATE (decl);
256 error ("invalid member template declaration `%D'", decl);
258 return error_mark_node;
261 /* Returns the template nesting level of the indicated class TYPE.
271 A<T>::B<U> has depth two, while A<T> has depth one.
272 Both A<T>::B<int> and A<int>::B<U> have depth one, if
273 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
276 This function is guaranteed to return 0 if passed NULL_TREE so
277 that, for example, `template_class_depth (current_class_type)' is
281 template_class_depth_real (tree type, int count_specializations)
286 type && TREE_CODE (type) != NAMESPACE_DECL;
287 type = (TREE_CODE (type) == FUNCTION_DECL)
288 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
290 if (TREE_CODE (type) != FUNCTION_DECL)
292 if (CLASSTYPE_TEMPLATE_INFO (type)
293 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
294 && ((count_specializations
295 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
296 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
301 if (DECL_TEMPLATE_INFO (type)
302 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
303 && ((count_specializations
304 && DECL_TEMPLATE_SPECIALIZATION (type))
305 || uses_template_parms (DECL_TI_ARGS (type))))
313 /* Returns the template nesting level of the indicated class TYPE.
314 Like template_class_depth_real, but instantiations do not count in
318 template_class_depth (tree type)
320 return template_class_depth_real (type, /*count_specializations=*/0);
323 /* Returns 1 if processing DECL as part of do_pending_inlines
324 needs us to push template parms. */
327 inline_needs_template_parms (tree decl)
329 if (! DECL_TEMPLATE_INFO (decl))
332 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
333 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
336 /* Subroutine of maybe_begin_member_template_processing.
337 Push the template parms in PARMS, starting from LEVELS steps into the
338 chain, and ending at the beginning, since template parms are listed
342 push_inline_template_parms_recursive (tree parmlist, int levels)
344 tree parms = TREE_VALUE (parmlist);
348 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
350 ++processing_template_decl;
351 current_template_parms
352 = tree_cons (size_int (processing_template_decl),
353 parms, current_template_parms);
354 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
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);
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);
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 if (current_namespace
735 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
737 pedwarn ("specializing `%#T' in different namespace", type);
738 cp_pedwarn_at (" from definition of `%#D'",
739 CLASSTYPE_TI_TEMPLATE (type));
741 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
742 if (processing_template_decl)
743 push_template_decl (TYPE_MAIN_DECL (type));
745 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
746 error ("specialization of `%T' after instantiation", type);
748 else if (CLASS_TYPE_P (type)
749 && !CLASSTYPE_USE_TEMPLATE (type)
750 && CLASSTYPE_TEMPLATE_INFO (type)
751 && context && CLASS_TYPE_P (context)
752 && CLASSTYPE_TEMPLATE_INFO (context))
754 /* This is for an explicit specialization of member class
755 template according to [temp.expl.spec/18]:
757 template <> template <class U> class C<int>::D;
759 The context `C<int>' must be an implicit instantiation.
760 Otherwise this is just a member class template declared
763 template <> class C<int> { template <class U> class D; };
764 template <> template <class U> class C<int>::D;
766 In the first case, `C<int>::D' is a specialization of `C<T>::D'
767 while in the second case, `C<int>::D' is a primary template
768 and `C<T>::D' may not exist. */
770 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
771 && !COMPLETE_TYPE_P (type))
775 if (current_namespace
776 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
778 pedwarn ("specializing `%#T' in different namespace", type);
779 cp_pedwarn_at (" from definition of `%#D'",
780 CLASSTYPE_TI_TEMPLATE (type));
783 /* Check for invalid specialization after instantiation:
785 template <> template <> class C<int>::D<int>;
786 template <> template <class U> class C<int>::D; */
788 for (t = DECL_TEMPLATE_INSTANTIATIONS
789 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
790 t; t = TREE_CHAIN (t))
791 if (TREE_VALUE (t) != type
792 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
793 error ("specialization `%T' after instantiation `%T'",
794 type, TREE_VALUE (t));
796 /* Mark TYPE as a specialization. And as a result, we only
797 have one level of template argument for the innermost
799 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
800 CLASSTYPE_TI_ARGS (type)
801 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
804 else if (processing_specialization)
805 error ("explicit specialization of non-template `%T'", type);
808 /* Retrieve the specialization (in the sense of [temp.spec] - a
809 specialization is either an instantiation or an explicit
810 specialization) of TMPL for the given template ARGS. If there is
811 no such specialization, return NULL_TREE. The ARGS are a vector of
812 arguments, or a vector of vectors of arguments, in the case of
813 templates with more than one level of parameters. */
816 retrieve_specialization (tree tmpl, tree args)
820 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
822 /* There should be as many levels of arguments as there are
823 levels of parameters. */
824 my_friendly_assert (TMPL_ARGS_DEPTH (args)
825 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
828 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
831 if (comp_template_args (TREE_PURPOSE (s), args))
832 return TREE_VALUE (s);
837 /* Like retrieve_specialization, but for local declarations. */
840 retrieve_local_specialization (tree tmpl)
842 tree spec = htab_find_with_hash (local_specializations, tmpl,
843 htab_hash_pointer (tmpl));
844 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
847 /* Returns nonzero iff DECL is a specialization of TMPL. */
850 is_specialization_of (tree decl, tree tmpl)
854 if (TREE_CODE (decl) == FUNCTION_DECL)
858 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
864 my_friendly_assert (TREE_CODE (decl) == TYPE_DECL, 0);
866 for (t = TREE_TYPE (decl);
868 t = CLASSTYPE_USE_TEMPLATE (t)
869 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
870 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
877 /* Register the specialization SPEC as a specialization of TMPL with
878 the indicated ARGS. Returns SPEC, or an equivalent prior
879 declaration, if available. */
882 register_specialization (tree spec, tree tmpl, tree args)
886 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
888 if (TREE_CODE (spec) == FUNCTION_DECL
889 && uses_template_parms (DECL_TI_ARGS (spec)))
890 /* This is the FUNCTION_DECL for a partial instantiation. Don't
891 register it; we want the corresponding TEMPLATE_DECL instead.
892 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
893 the more obvious `uses_template_parms (spec)' to avoid problems
894 with default function arguments. In particular, given
897 template <class T> void f(T t1, T t = T())
899 the default argument expression is not substituted for in an
900 instantiation unless and until it is actually needed. */
903 /* There should be as many levels of arguments as there are
904 levels of parameters. */
905 my_friendly_assert (TMPL_ARGS_DEPTH (args)
906 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
909 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
913 tree fn = TREE_VALUE (s);
915 /* We can sometimes try to re-register a specialization that we've
916 already got. In particular, regenerate_decl_from_template
917 calls duplicate_decls which will update the specialization
918 list. But, we'll still get called again here anyhow. It's
919 more convenient to simply allow this than to try to prevent it. */
922 else if (comp_template_args (TREE_PURPOSE (s), args))
924 if (DECL_TEMPLATE_SPECIALIZATION (spec))
926 if (DECL_TEMPLATE_INSTANTIATION (fn))
929 || DECL_EXPLICIT_INSTANTIATION (fn))
931 error ("specialization of %D after instantiation",
937 /* This situation should occur only if the first
938 specialization is an implicit instantiation,
939 the second is an explicit specialization, and
940 the implicit instantiation has not yet been
941 used. That situation can occur if we have
942 implicitly instantiated a member function and
943 then specialized it later.
945 We can also wind up here if a friend
946 declaration that looked like an instantiation
947 turns out to be a specialization:
949 template <class T> void foo(T);
950 class S { friend void foo<>(int) };
951 template <> void foo(int);
953 We transform the existing DECL in place so that
954 any pointers to it become pointers to the
957 If there was a definition for the template, but
958 not for the specialization, we want this to
959 look as if there is no definition, and vice
961 DECL_INITIAL (fn) = NULL_TREE;
962 duplicate_decls (spec, fn);
967 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
969 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
970 /* Dup decl failed, but this is a new
971 definition. Set the line number so any errors
972 match this new definition. */
973 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
981 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
982 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
987 /* Unregister the specialization SPEC as a specialization of TMPL.
988 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
989 if the SPEC was listed as a specialization of TMPL. */
992 reregister_specialization (tree spec, tree tmpl, tree new_spec)
996 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
998 s = &TREE_CHAIN (*s))
999 if (TREE_VALUE (*s) == spec)
1002 *s = TREE_CHAIN (*s);
1004 TREE_VALUE (*s) = new_spec;
1011 /* Compare an entry in the local specializations hash table P1 (which
1012 is really a pointer to a TREE_LIST) with P2 (which is really a
1016 eq_local_specializations (const void *p1, const void *p2)
1018 return TREE_VALUE ((tree) p1) == (tree) p2;
1021 /* Hash P1, an entry in the local specializations table. */
1024 hash_local_specialization (const void* p1)
1026 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1029 /* Like register_specialization, but for local declarations. We are
1030 registering SPEC, an instantiation of TMPL. */
1033 register_local_specialization (tree spec, tree tmpl)
1037 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1038 htab_hash_pointer (tmpl), INSERT);
1039 *slot = build_tree_list (spec, tmpl);
1042 /* Print the list of candidate FNS in an error message. */
1045 print_candidates (tree fns)
1049 const char *str = "candidates are:";
1051 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1055 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1056 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
1061 /* Returns the template (one of the functions given by TEMPLATE_ID)
1062 which can be specialized to match the indicated DECL with the
1063 explicit template args given in TEMPLATE_ID. The DECL may be
1064 NULL_TREE if none is available. In that case, the functions in
1065 TEMPLATE_ID are non-members.
1067 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1068 specialization of a member template.
1070 The template args (those explicitly specified and those deduced)
1071 are output in a newly created vector *TARGS_OUT.
1073 If it is impossible to determine the result, an error message is
1074 issued. The error_mark_node is returned to indicate failure. */
1077 determine_specialization (tree template_id,
1080 int need_member_template)
1084 tree explicit_targs;
1085 tree candidates = NULL_TREE;
1086 tree templates = NULL_TREE;
1088 *targs_out = NULL_TREE;
1090 if (template_id == error_mark_node)
1091 return error_mark_node;
1093 fns = TREE_OPERAND (template_id, 0);
1094 explicit_targs = TREE_OPERAND (template_id, 1);
1096 if (fns == error_mark_node)
1097 return error_mark_node;
1099 /* Check for baselinks. */
1100 if (BASELINK_P (fns))
1101 fns = BASELINK_FUNCTIONS (fns);
1103 if (!is_overloaded_fn (fns))
1105 error ("`%D' is not a function template", fns);
1106 return error_mark_node;
1109 for (; fns; fns = OVL_NEXT (fns))
1111 tree fn = OVL_CURRENT (fns);
1113 if (TREE_CODE (fn) == TEMPLATE_DECL)
1115 tree decl_arg_types;
1117 /* DECL might be a specialization of FN. */
1119 /* Adjust the type of DECL in case FN is a static member. */
1120 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1121 if (DECL_STATIC_FUNCTION_P (fn)
1122 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1123 decl_arg_types = TREE_CHAIN (decl_arg_types);
1125 /* Check that the number of function parameters matches.
1127 template <class T> void f(int i = 0);
1128 template <> void f<int>();
1129 The specialization f<int> is invalid but is not caught
1130 by get_bindings below. */
1132 if (list_length (TYPE_ARG_TYPES (TREE_TYPE (fn)))
1133 != list_length (decl_arg_types))
1136 /* See whether this function might be a specialization of this
1138 targs = get_bindings (fn, decl, explicit_targs);
1141 /* We cannot deduce template arguments that when used to
1142 specialize TMPL will produce DECL. */
1145 /* Save this template, and the arguments deduced. */
1146 templates = tree_cons (targs, fn, templates);
1148 else if (need_member_template)
1149 /* FN is an ordinary member function, and we need a
1150 specialization of a member template. */
1152 else if (TREE_CODE (fn) != FUNCTION_DECL)
1153 /* We can get IDENTIFIER_NODEs here in certain erroneous
1156 else if (!DECL_FUNCTION_MEMBER_P (fn))
1157 /* This is just an ordinary non-member function. Nothing can
1158 be a specialization of that. */
1160 else if (DECL_ARTIFICIAL (fn))
1161 /* Cannot specialize functions that are created implicitly. */
1165 tree decl_arg_types;
1167 /* This is an ordinary member function. However, since
1168 we're here, we can assume it's enclosing class is a
1169 template class. For example,
1171 template <typename T> struct S { void f(); };
1172 template <> void S<int>::f() {}
1174 Here, S<int>::f is a non-template, but S<int> is a
1175 template class. If FN has the same type as DECL, we
1176 might be in business. */
1178 if (!DECL_TEMPLATE_INFO (fn))
1179 /* Its enclosing class is an explicit specialization
1180 of a template class. This is not a candidate. */
1183 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1184 TREE_TYPE (TREE_TYPE (fn))))
1185 /* The return types differ. */
1188 /* Adjust the type of DECL in case FN is a static member. */
1189 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1190 if (DECL_STATIC_FUNCTION_P (fn)
1191 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1192 decl_arg_types = TREE_CHAIN (decl_arg_types);
1194 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1197 candidates = tree_cons (NULL_TREE, fn, candidates);
1201 if (templates && TREE_CHAIN (templates))
1207 It is possible for a specialization with a given function
1208 signature to be instantiated from more than one function
1209 template. In such cases, explicit specification of the
1210 template arguments must be used to uniquely identify the
1211 function template specialization being specialized.
1213 Note that here, there's no suggestion that we're supposed to
1214 determine which of the candidate templates is most
1215 specialized. However, we, also have:
1219 Partial ordering of overloaded function template
1220 declarations is used in the following contexts to select
1221 the function template to which a function template
1222 specialization refers:
1224 -- when an explicit specialization refers to a function
1227 So, we do use the partial ordering rules, at least for now.
1228 This extension can only serve to make invalid programs valid,
1229 so it's safe. And, there is strong anecdotal evidence that
1230 the committee intended the partial ordering rules to apply;
1231 the EDG front-end has that behavior, and John Spicer claims
1232 that the committee simply forgot to delete the wording in
1233 [temp.expl.spec]. */
1234 tree tmpl = most_specialized (templates, decl, explicit_targs);
1235 if (tmpl && tmpl != error_mark_node)
1237 targs = get_bindings (tmpl, decl, explicit_targs);
1238 templates = tree_cons (targs, tmpl, NULL_TREE);
1242 if (templates == NULL_TREE && candidates == NULL_TREE)
1244 cp_error_at ("template-id `%D' for `%+D' does not match any template declaration",
1246 return error_mark_node;
1248 else if ((templates && TREE_CHAIN (templates))
1249 || (candidates && TREE_CHAIN (candidates))
1250 || (templates && candidates))
1252 cp_error_at ("ambiguous template specialization `%D' for `%+D'",
1254 chainon (candidates, templates);
1255 print_candidates (candidates);
1256 return error_mark_node;
1259 /* We have one, and exactly one, match. */
1262 /* It was a specialization of an ordinary member function in a
1264 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1265 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1268 /* It was a specialization of a template. */
1269 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1270 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1272 *targs_out = copy_node (targs);
1273 SET_TMPL_ARGS_LEVEL (*targs_out,
1274 TMPL_ARGS_DEPTH (*targs_out),
1275 TREE_PURPOSE (templates));
1278 *targs_out = TREE_PURPOSE (templates);
1279 return TREE_VALUE (templates);
1282 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1283 but with the default argument values filled in from those in the
1287 copy_default_args_to_explicit_spec_1 (tree spec_types,
1290 tree new_spec_types;
1295 if (spec_types == void_list_node)
1296 return void_list_node;
1298 /* Substitute into the rest of the list. */
1300 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1301 TREE_CHAIN (tmpl_types));
1303 /* Add the default argument for this parameter. */
1304 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1305 TREE_VALUE (spec_types),
1309 /* DECL is an explicit specialization. Replicate default arguments
1310 from the template it specializes. (That way, code like:
1312 template <class T> void f(T = 3);
1313 template <> void f(double);
1316 works, as required.) An alternative approach would be to look up
1317 the correct default arguments at the call-site, but this approach
1318 is consistent with how implicit instantiations are handled. */
1321 copy_default_args_to_explicit_spec (tree decl)
1326 tree new_spec_types;
1330 tree object_type = NULL_TREE;
1331 tree in_charge = NULL_TREE;
1332 tree vtt = NULL_TREE;
1334 /* See if there's anything we need to do. */
1335 tmpl = DECL_TI_TEMPLATE (decl);
1336 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1337 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1338 if (TREE_PURPOSE (t))
1343 old_type = TREE_TYPE (decl);
1344 spec_types = TYPE_ARG_TYPES (old_type);
1346 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1348 /* Remove the this pointer, but remember the object's type for
1350 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1351 spec_types = TREE_CHAIN (spec_types);
1352 tmpl_types = TREE_CHAIN (tmpl_types);
1354 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1356 /* DECL may contain more parameters than TMPL due to the extra
1357 in-charge parameter in constructors and destructors. */
1358 in_charge = spec_types;
1359 spec_types = TREE_CHAIN (spec_types);
1361 if (DECL_HAS_VTT_PARM_P (decl))
1364 spec_types = TREE_CHAIN (spec_types);
1368 /* Compute the merged default arguments. */
1370 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1372 /* Compute the new FUNCTION_TYPE. */
1376 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1381 /* Put the in-charge parameter back. */
1382 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1383 TREE_VALUE (in_charge),
1386 new_type = build_cplus_method_type (object_type,
1387 TREE_TYPE (old_type),
1391 new_type = build_function_type (TREE_TYPE (old_type),
1393 new_type = build_type_attribute_variant (new_type,
1394 TYPE_ATTRIBUTES (old_type));
1395 new_type = build_exception_variant (new_type,
1396 TYPE_RAISES_EXCEPTIONS (old_type));
1397 TREE_TYPE (decl) = new_type;
1400 /* Check to see if the function just declared, as indicated in
1401 DECLARATOR, and in DECL, is a specialization of a function
1402 template. We may also discover that the declaration is an explicit
1403 instantiation at this point.
1405 Returns DECL, or an equivalent declaration that should be used
1406 instead if all goes well. Issues an error message if something is
1407 amiss. Returns error_mark_node if the error is not easily
1410 FLAGS is a bitmask consisting of the following flags:
1412 2: The function has a definition.
1413 4: The function is a friend.
1415 The TEMPLATE_COUNT is the number of references to qualifying
1416 template classes that appeared in the name of the function. For
1419 template <class T> struct S { void f(); };
1422 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1423 classes are not counted in the TEMPLATE_COUNT, so that in
1425 template <class T> struct S {};
1426 template <> struct S<int> { void f(); }
1427 template <> void S<int>::f();
1429 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1430 invalid; there should be no template <>.)
1432 If the function is a specialization, it is marked as such via
1433 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1434 is set up correctly, and it is added to the list of specializations
1435 for that template. */
1438 check_explicit_specialization (tree declarator,
1443 int have_def = flags & 2;
1444 int is_friend = flags & 4;
1445 int specialization = 0;
1446 int explicit_instantiation = 0;
1447 int member_specialization = 0;
1448 tree ctype = DECL_CLASS_CONTEXT (decl);
1449 tree dname = DECL_NAME (decl);
1452 tsk = current_tmpl_spec_kind (template_count);
1457 if (processing_specialization)
1460 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1462 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1465 /* This could be something like:
1467 template <class T> void f(T);
1468 class S { friend void f<>(int); } */
1472 /* This case handles bogus declarations like template <>
1473 template <class T> void f<int>(); */
1475 error ("template-id `%D' in declaration of primary template",
1482 case tsk_invalid_member_spec:
1483 /* The error has already been reported in
1484 check_specialization_scope. */
1485 return error_mark_node;
1487 case tsk_invalid_expl_inst:
1488 error ("template parameter list used in explicit instantiation");
1494 error ("definition provided for explicit instantiation");
1496 explicit_instantiation = 1;
1499 case tsk_excessive_parms:
1500 error ("too many template parameter lists in declaration of `%D'",
1502 return error_mark_node;
1506 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1508 member_specialization = 1;
1513 case tsk_insufficient_parms:
1514 if (template_header_count)
1516 error("too few template parameter lists in declaration of `%D'",
1520 else if (ctype != NULL_TREE
1521 && !TYPE_BEING_DEFINED (ctype)
1522 && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype)
1525 /* For backwards compatibility, we accept:
1527 template <class T> struct S { void f(); };
1528 void S<int>::f() {} // Missing template <>
1530 That used to be valid C++. */
1533 ("explicit specialization not preceded by `template <>'");
1535 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1540 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1542 /* This case handles bogus declarations like template <>
1543 template <class T> void f<int>(); */
1545 if (uses_template_parms (declarator))
1546 error ("partial specialization `%D' of function template",
1549 error ("template-id `%D' in declaration of primary template",
1554 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1555 /* This is a specialization of a member template, without
1556 specialization the containing class. Something like:
1558 template <class T> struct S {
1559 template <class U> void f (U);
1561 template <> template <class U> void S<int>::f(U) {}
1563 That's a specialization -- but of the entire template. */
1571 if (specialization || member_specialization)
1573 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1574 for (; t; t = TREE_CHAIN (t))
1575 if (TREE_PURPOSE (t))
1578 ("default argument specified in explicit specialization");
1581 if (current_lang_name == lang_name_c)
1582 error ("template specialization with C linkage");
1585 if (specialization || member_specialization || explicit_instantiation)
1587 tree tmpl = NULL_TREE;
1588 tree targs = NULL_TREE;
1590 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1591 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1595 my_friendly_assert (TREE_CODE (declarator) == IDENTIFIER_NODE, 0);
1600 /* If there is no class context, the explicit instantiation
1601 must be at namespace scope. */
1602 my_friendly_assert (DECL_NAMESPACE_SCOPE_P (decl), 20030625);
1604 /* Find the namespace binding, using the declaration
1606 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1609 declarator = lookup_template_function (fns, NULL_TREE);
1612 if (declarator == error_mark_node)
1613 return error_mark_node;
1615 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1617 if (!explicit_instantiation)
1618 /* A specialization in class scope. This is invalid,
1619 but the error will already have been flagged by
1620 check_specialization_scope. */
1621 return error_mark_node;
1624 /* It's not valid to write an explicit instantiation in
1627 class C { template void f(); }
1629 This case is caught by the parser. However, on
1632 template class C { void f(); };
1634 (which is invalid) we can get here. The error will be
1641 else if (ctype != NULL_TREE
1642 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1645 /* Find the list of functions in ctype that have the same
1646 name as the declared function. */
1647 tree name = TREE_OPERAND (declarator, 0);
1648 tree fns = NULL_TREE;
1651 if (constructor_name_p (name, ctype))
1653 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1655 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1656 : !TYPE_HAS_DESTRUCTOR (ctype))
1658 /* From [temp.expl.spec]:
1660 If such an explicit specialization for the member
1661 of a class template names an implicitly-declared
1662 special member function (clause _special_), the
1663 program is ill-formed.
1665 Similar language is found in [temp.explicit]. */
1666 error ("specialization of implicitly-declared special member function");
1667 return error_mark_node;
1670 name = is_constructor ? ctor_identifier : dtor_identifier;
1673 if (!DECL_CONV_FN_P (decl))
1675 idx = lookup_fnfields_1 (ctype, name);
1677 fns = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (ctype), idx);
1683 /* For a type-conversion operator, we cannot do a
1684 name-based lookup. We might be looking for `operator
1685 int' which will be a specialization of `operator T'.
1686 So, we find *all* the conversion operators, and then
1687 select from them. */
1690 methods = CLASSTYPE_METHOD_VEC (ctype);
1692 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1693 idx < TREE_VEC_LENGTH (methods); ++idx)
1695 tree ovl = TREE_VEC_ELT (methods, idx);
1697 if (!ovl || !DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1698 /* There are no more conversion functions. */
1701 /* Glue all these conversion functions together
1702 with those we already have. */
1703 for (; ovl; ovl = OVL_NEXT (ovl))
1704 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1708 if (fns == NULL_TREE)
1710 error ("no member function `%D' declared in `%T'",
1712 return error_mark_node;
1715 TREE_OPERAND (declarator, 0) = fns;
1718 /* Figure out what exactly is being specialized at this point.
1719 Note that for an explicit instantiation, even one for a
1720 member function, we cannot tell apriori whether the
1721 instantiation is for a member template, or just a member
1722 function of a template class. Even if a member template is
1723 being instantiated, the member template arguments may be
1724 elided if they can be deduced from the rest of the
1726 tmpl = determine_specialization (declarator, decl,
1728 member_specialization);
1730 if (!tmpl || tmpl == error_mark_node)
1731 /* We couldn't figure out what this declaration was
1733 return error_mark_node;
1736 tree gen_tmpl = most_general_template (tmpl);
1738 if (explicit_instantiation)
1740 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
1741 is done by do_decl_instantiation later. */
1743 int arg_depth = TMPL_ARGS_DEPTH (targs);
1744 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
1746 if (arg_depth > parm_depth)
1748 /* If TMPL is not the most general template (for
1749 example, if TMPL is a friend template that is
1750 injected into namespace scope), then there will
1751 be too many levels of TARGS. Remove some of them
1756 new_targs = make_tree_vec (parm_depth);
1757 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
1758 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
1759 = TREE_VEC_ELT (targs, i);
1763 return instantiate_template (tmpl, targs, tf_error);
1766 /* If we thought that the DECL was a member function, but it
1767 turns out to be specializing a static member function,
1768 make DECL a static member function as well. We also have
1769 to adjust last_function_parms to avoid confusing
1770 start_function later. */
1771 if (DECL_STATIC_FUNCTION_P (tmpl)
1772 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1774 revert_static_member_fn (decl);
1775 last_function_parms = TREE_CHAIN (last_function_parms);
1778 /* If this is a specialization of a member template of a
1779 template class. In we want to return the TEMPLATE_DECL,
1780 not the specialization of it. */
1781 if (tsk == tsk_template)
1783 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
1784 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
1787 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
1788 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
1789 = DECL_SOURCE_LOCATION (decl);
1794 /* Set up the DECL_TEMPLATE_INFO for DECL. */
1795 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
1797 /* Inherit default function arguments from the template
1798 DECL is specializing. */
1799 copy_default_args_to_explicit_spec (decl);
1801 /* This specialization has the same protection as the
1802 template it specializes. */
1803 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
1804 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
1806 if (is_friend && !have_def)
1807 /* This is not really a declaration of a specialization.
1808 It's just the name of an instantiation. But, it's not
1809 a request for an instantiation, either. */
1810 SET_DECL_IMPLICIT_INSTANTIATION (decl);
1811 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
1812 /* This is indeed a specialization. In case of constructors
1813 and destructors, we need in-charge and not-in-charge
1814 versions in V3 ABI. */
1815 clone_function_decl (decl, /*update_method_vec_p=*/0);
1817 /* Register this specialization so that we can find it
1819 decl = register_specialization (decl, gen_tmpl, targs);
1826 /* TYPE is being declared. Verify that the use of template headers
1827 and such is reasonable. Issue error messages if not. */
1830 maybe_check_template_type (tree type)
1832 if (template_header_count)
1834 /* We are in the scope of some `template <...>' header. */
1837 = template_class_depth_real (TYPE_CONTEXT (type),
1838 /*count_specializations=*/1);
1840 if (template_header_count <= context_depth)
1841 /* This is OK; the template headers are for the context. We
1842 are actually too lenient here; like
1843 check_explicit_specialization we should consider the number
1844 of template types included in the actual declaration. For
1847 template <class T> struct S {
1848 template <class U> template <class V>
1854 template <class T> struct S {
1855 template <class U> struct I;
1858 template <class T> template <class U.
1863 else if (template_header_count > context_depth + 1)
1864 /* There are two many template parameter lists. */
1865 error ("too many template parameter lists in declaration of `%T'", type);
1869 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
1870 parameters. These are represented in the same format used for
1871 DECL_TEMPLATE_PARMS. */
1873 int comp_template_parms (tree parms1, tree parms2)
1878 if (parms1 == parms2)
1881 for (p1 = parms1, p2 = parms2;
1882 p1 != NULL_TREE && p2 != NULL_TREE;
1883 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
1885 tree t1 = TREE_VALUE (p1);
1886 tree t2 = TREE_VALUE (p2);
1889 my_friendly_assert (TREE_CODE (t1) == TREE_VEC, 0);
1890 my_friendly_assert (TREE_CODE (t2) == TREE_VEC, 0);
1892 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
1895 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
1897 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
1898 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
1900 if (TREE_CODE (parm1) != TREE_CODE (parm2))
1903 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
1905 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
1910 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
1911 /* One set of parameters has more parameters lists than the
1918 /* Complain if DECL shadows a template parameter.
1920 [temp.local]: A template-parameter shall not be redeclared within its
1921 scope (including nested scopes). */
1924 check_template_shadow (tree decl)
1928 /* If we're not in a template, we can't possibly shadow a template
1930 if (!current_template_parms)
1933 /* Figure out what we're shadowing. */
1934 if (TREE_CODE (decl) == OVERLOAD)
1935 decl = OVL_CURRENT (decl);
1936 olddecl = IDENTIFIER_VALUE (DECL_NAME (decl));
1938 /* If there's no previous binding for this name, we're not shadowing
1939 anything, let alone a template parameter. */
1943 /* If we're not shadowing a template parameter, we're done. Note
1944 that OLDDECL might be an OVERLOAD (or perhaps even an
1945 ERROR_MARK), so we can't just blithely assume it to be a _DECL
1947 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
1950 /* We check for decl != olddecl to avoid bogus errors for using a
1951 name inside a class. We check TPFI to avoid duplicate errors for
1952 inline member templates. */
1954 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
1957 cp_error_at ("declaration of `%#D'", decl);
1958 cp_error_at (" shadows template parm `%#D'", olddecl);
1961 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
1962 ORIG_LEVEL, DECL, and TYPE. */
1965 build_template_parm_index (int index,
1971 tree t = make_node (TEMPLATE_PARM_INDEX);
1972 TEMPLATE_PARM_IDX (t) = index;
1973 TEMPLATE_PARM_LEVEL (t) = level;
1974 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
1975 TEMPLATE_PARM_DECL (t) = decl;
1976 TREE_TYPE (t) = type;
1977 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
1978 TREE_READONLY (t) = TREE_READONLY (decl);
1983 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
1984 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
1985 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
1986 new one is created. */
1989 reduce_template_parm_level (tree index, tree type, int levels)
1991 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
1992 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
1993 != TEMPLATE_PARM_LEVEL (index) - levels))
1995 tree orig_decl = TEMPLATE_PARM_DECL (index);
1998 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
1999 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2000 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2001 DECL_ARTIFICIAL (decl) = 1;
2002 SET_DECL_TEMPLATE_PARM_P (decl);
2004 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2005 TEMPLATE_PARM_LEVEL (index) - levels,
2006 TEMPLATE_PARM_ORIG_LEVEL (index),
2008 TEMPLATE_PARM_DESCENDANTS (index) = t;
2010 /* Template template parameters need this. */
2011 DECL_TEMPLATE_PARMS (decl)
2012 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2015 return TEMPLATE_PARM_DESCENDANTS (index);
2018 /* Process information from new template parameter NEXT and append it to the
2019 LIST being built. */
2022 process_template_parm (tree list, tree next)
2030 my_friendly_assert (TREE_CODE (parm) == TREE_LIST, 259);
2031 defval = TREE_PURPOSE (parm);
2032 parm = TREE_VALUE (parm);
2033 is_type = TREE_PURPOSE (parm) == class_type_node;
2037 tree p = TREE_VALUE (tree_last (list));
2039 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2040 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2042 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2050 my_friendly_assert (TREE_CODE (TREE_PURPOSE (parm)) == TREE_LIST, 260);
2051 /* is a const-param */
2052 parm = grokdeclarator (TREE_VALUE (parm), TREE_PURPOSE (parm),
2054 SET_DECL_TEMPLATE_PARM_P (parm);
2058 The top-level cv-qualifiers on the template-parameter are
2059 ignored when determining its type. */
2060 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2062 /* A template parameter is not modifiable. */
2063 TREE_READONLY (parm) = TREE_CONSTANT (parm) = 1;
2064 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2065 TREE_TYPE (parm) = void_type_node;
2066 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2067 TREE_CONSTANT (decl) = TREE_READONLY (decl) = 1;
2068 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2069 = build_template_parm_index (idx, processing_template_decl,
2070 processing_template_decl,
2071 decl, TREE_TYPE (parm));
2076 parm = TREE_VALUE (parm);
2078 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2080 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2081 /* This is for distinguishing between real templates and template
2082 template parameters */
2083 TREE_TYPE (parm) = t;
2084 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2089 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2090 /* parm is either IDENTIFIER_NODE or NULL_TREE */
2091 decl = build_decl (TYPE_DECL, parm, t);
2094 TYPE_NAME (t) = decl;
2095 TYPE_STUB_DECL (t) = decl;
2097 TEMPLATE_TYPE_PARM_INDEX (t)
2098 = build_template_parm_index (idx, processing_template_decl,
2099 processing_template_decl,
2100 decl, TREE_TYPE (parm));
2102 DECL_ARTIFICIAL (decl) = 1;
2103 SET_DECL_TEMPLATE_PARM_P (decl);
2105 parm = build_tree_list (defval, parm);
2106 return chainon (list, parm);
2109 /* The end of a template parameter list has been reached. Process the
2110 tree list into a parameter vector, converting each parameter into a more
2111 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2115 end_template_parm_list (tree parms)
2119 tree saved_parmlist = make_tree_vec (list_length (parms));
2121 current_template_parms
2122 = tree_cons (size_int (processing_template_decl),
2123 saved_parmlist, current_template_parms);
2125 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2127 next = TREE_CHAIN (parm);
2128 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2129 TREE_CHAIN (parm) = NULL_TREE;
2132 --processing_template_parmlist;
2134 return saved_parmlist;
2137 /* end_template_decl is called after a template declaration is seen. */
2140 end_template_decl (void)
2142 reset_specialization ();
2144 if (! processing_template_decl)
2147 /* This matches the pushlevel in begin_template_parm_list. */
2150 --processing_template_decl;
2151 current_template_parms = TREE_CHAIN (current_template_parms);
2154 /* Given a template argument vector containing the template PARMS.
2155 The innermost PARMS are given first. */
2158 current_template_args (void)
2161 tree args = NULL_TREE;
2162 int length = TMPL_PARMS_DEPTH (current_template_parms);
2165 /* If there is only one level of template parameters, we do not
2166 create a TREE_VEC of TREE_VECs. Instead, we return a single
2167 TREE_VEC containing the arguments. */
2169 args = make_tree_vec (length);
2171 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2173 tree a = copy_node (TREE_VALUE (header));
2176 TREE_TYPE (a) = NULL_TREE;
2177 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2179 tree t = TREE_VEC_ELT (a, i);
2181 /* T will be a list if we are called from within a
2182 begin/end_template_parm_list pair, but a vector directly
2183 if within a begin/end_member_template_processing pair. */
2184 if (TREE_CODE (t) == TREE_LIST)
2188 if (TREE_CODE (t) == TYPE_DECL
2189 || TREE_CODE (t) == TEMPLATE_DECL)
2192 t = DECL_INITIAL (t);
2193 TREE_VEC_ELT (a, i) = t;
2198 TREE_VEC_ELT (args, --l) = a;
2206 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2207 template PARMS. Used by push_template_decl below. */
2210 build_template_decl (tree decl, tree parms)
2212 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2213 DECL_TEMPLATE_PARMS (tmpl) = parms;
2214 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2215 if (DECL_LANG_SPECIFIC (decl))
2217 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2218 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2219 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2220 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2221 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2222 if (DECL_OVERLOADED_OPERATOR_P (decl))
2223 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2224 DECL_OVERLOADED_OPERATOR_P (decl));
2230 struct template_parm_data
2232 /* The level of the template parameters we are currently
2236 /* The index of the specialization argument we are currently
2240 /* An array whose size is the number of template parameters. The
2241 elements are nonzero if the parameter has been used in any one
2242 of the arguments processed so far. */
2245 /* An array whose size is the number of template arguments. The
2246 elements are nonzero if the argument makes use of template
2247 parameters of this level. */
2248 int* arg_uses_template_parms;
2251 /* Subroutine of push_template_decl used to see if each template
2252 parameter in a partial specialization is used in the explicit
2253 argument list. If T is of the LEVEL given in DATA (which is
2254 treated as a template_parm_data*), then DATA->PARMS is marked
2258 mark_template_parm (tree t, void* data)
2262 struct template_parm_data* tpd = (struct template_parm_data*) data;
2264 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2266 level = TEMPLATE_PARM_LEVEL (t);
2267 idx = TEMPLATE_PARM_IDX (t);
2271 level = TEMPLATE_TYPE_LEVEL (t);
2272 idx = TEMPLATE_TYPE_IDX (t);
2275 if (level == tpd->level)
2277 tpd->parms[idx] = 1;
2278 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2281 /* Return zero so that for_each_template_parm will continue the
2282 traversal of the tree; we want to mark *every* template parm. */
2286 /* Process the partial specialization DECL. */
2289 process_partial_specialization (tree decl)
2291 tree type = TREE_TYPE (decl);
2292 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2293 tree specargs = CLASSTYPE_TI_ARGS (type);
2294 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2295 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2296 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2297 int nargs = TREE_VEC_LENGTH (inner_args);
2298 int ntparms = TREE_VEC_LENGTH (inner_parms);
2300 int did_error_intro = 0;
2301 struct template_parm_data tpd;
2302 struct template_parm_data tpd2;
2304 /* We check that each of the template parameters given in the
2305 partial specialization is used in the argument list to the
2306 specialization. For example:
2308 template <class T> struct S;
2309 template <class T> struct S<T*>;
2311 The second declaration is OK because `T*' uses the template
2312 parameter T, whereas
2314 template <class T> struct S<int>;
2316 is no good. Even trickier is:
2327 The S2<T> declaration is actually invalid; it is a
2328 full-specialization. Of course,
2331 struct S2<T (*)(U)>;
2333 or some such would have been OK. */
2334 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2335 tpd.parms = alloca (sizeof (int) * ntparms);
2336 memset (tpd.parms, 0, sizeof (int) * ntparms);
2338 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2339 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2340 for (i = 0; i < nargs; ++i)
2342 tpd.current_arg = i;
2343 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2344 &mark_template_parm,
2348 for (i = 0; i < ntparms; ++i)
2349 if (tpd.parms[i] == 0)
2351 /* One of the template parms was not used in the
2353 if (!did_error_intro)
2355 error ("template parameters not used in partial specialization:");
2356 did_error_intro = 1;
2360 TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2363 /* [temp.class.spec]
2365 The argument list of the specialization shall not be identical to
2366 the implicit argument list of the primary template. */
2367 if (comp_template_args
2369 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2371 error ("partial specialization `%T' does not specialize any template arguments", type);
2373 /* [temp.class.spec]
2375 A partially specialized non-type argument expression shall not
2376 involve template parameters of the partial specialization except
2377 when the argument expression is a simple identifier.
2379 The type of a template parameter corresponding to a specialized
2380 non-type argument shall not be dependent on a parameter of the
2382 my_friendly_assert (nargs == DECL_NTPARMS (maintmpl), 0);
2384 for (i = 0; i < nargs; ++i)
2386 tree arg = TREE_VEC_ELT (inner_args, i);
2387 if (/* These first two lines are the `non-type' bit. */
2389 && TREE_CODE (arg) != TEMPLATE_DECL
2390 /* This next line is the `argument expression is not just a
2391 simple identifier' condition and also the `specialized
2392 non-type argument' bit. */
2393 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2395 if (tpd.arg_uses_template_parms[i])
2396 error ("template argument `%E' involves template parameter(s)", arg);
2399 /* Look at the corresponding template parameter,
2400 marking which template parameters its type depends
2403 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2408 /* We haven't yet initialized TPD2. Do so now. */
2409 tpd2.arg_uses_template_parms
2410 = alloca (sizeof (int) * nargs);
2411 /* The number of parameters here is the number in the
2412 main template, which, as checked in the assertion
2414 tpd2.parms = alloca (sizeof (int) * nargs);
2416 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2419 /* Mark the template parameters. But this time, we're
2420 looking for the template parameters of the main
2421 template, not in the specialization. */
2422 tpd2.current_arg = i;
2423 tpd2.arg_uses_template_parms[i] = 0;
2424 memset (tpd2.parms, 0, sizeof (int) * nargs);
2425 for_each_template_parm (type,
2426 &mark_template_parm,
2430 if (tpd2.arg_uses_template_parms [i])
2432 /* The type depended on some template parameters.
2433 If they are fully specialized in the
2434 specialization, that's OK. */
2436 for (j = 0; j < nargs; ++j)
2437 if (tpd2.parms[j] != 0
2438 && tpd.arg_uses_template_parms [j])
2440 error ("type `%T' of template argument `%E' depends on template parameter(s)",
2450 if (retrieve_specialization (maintmpl, specargs))
2451 /* We've already got this specialization. */
2454 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2455 = tree_cons (inner_args, inner_parms,
2456 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2457 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2461 /* Check that a template declaration's use of default arguments is not
2462 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2463 nonzero if DECL is the thing declared by a primary template.
2464 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2467 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2470 int last_level_to_check;
2475 A default template-argument shall not be specified in a
2476 function template declaration or a function template definition, nor
2477 in the template-parameter-list of the definition of a member of a
2480 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2481 /* You can't have a function template declaration in a local
2482 scope, nor you can you define a member of a class template in a
2486 if (current_class_type
2487 && !TYPE_BEING_DEFINED (current_class_type)
2488 && DECL_LANG_SPECIFIC (decl)
2489 /* If this is either a friend defined in the scope of the class
2490 or a member function. */
2491 && (DECL_FUNCTION_MEMBER_P (decl)
2492 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2493 : DECL_FRIEND_CONTEXT (decl)
2494 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2496 /* And, if it was a member function, it really was defined in
2497 the scope of the class. */
2498 && (!DECL_FUNCTION_MEMBER_P (decl)
2499 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2500 /* We already checked these parameters when the template was
2501 declared, so there's no need to do it again now. This function
2502 was defined in class scope, but we're processing it's body now
2503 that the class is complete. */
2508 If a template-parameter has a default template-argument, all
2509 subsequent template-parameters shall have a default
2510 template-argument supplied. */
2511 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2513 tree inner_parms = TREE_VALUE (parm_level);
2514 int ntparms = TREE_VEC_LENGTH (inner_parms);
2515 int seen_def_arg_p = 0;
2518 for (i = 0; i < ntparms; ++i)
2520 tree parm = TREE_VEC_ELT (inner_parms, i);
2521 if (TREE_PURPOSE (parm))
2523 else if (seen_def_arg_p)
2525 error ("no default argument for `%D'", TREE_VALUE (parm));
2526 /* For better subsequent error-recovery, we indicate that
2527 there should have been a default argument. */
2528 TREE_PURPOSE (parm) = error_mark_node;
2533 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2534 /* For an ordinary class template, default template arguments are
2535 allowed at the innermost level, e.g.:
2536 template <class T = int>
2538 but, in a partial specialization, they're not allowed even
2539 there, as we have in [temp.class.spec]:
2541 The template parameter list of a specialization shall not
2542 contain default template argument values.
2544 So, for a partial specialization, or for a function template,
2545 we look at all of them. */
2548 /* But, for a primary class template that is not a partial
2549 specialization we look at all template parameters except the
2551 parms = TREE_CHAIN (parms);
2553 /* Figure out what error message to issue. */
2554 if (TREE_CODE (decl) == FUNCTION_DECL)
2555 msg = "default template arguments may not be used in function templates";
2556 else if (is_partial)
2557 msg = "default template arguments may not be used in partial specializations";
2559 msg = "default argument for template parameter for class enclosing `%D'";
2561 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2562 /* If we're inside a class definition, there's no need to
2563 examine the parameters to the class itself. On the one
2564 hand, they will be checked when the class is defined, and,
2565 on the other, default arguments are valid in things like:
2566 template <class T = double>
2567 struct S { template <class U> void f(U); };
2568 Here the default argument for `S' has no bearing on the
2569 declaration of `f'. */
2570 last_level_to_check = template_class_depth (current_class_type) + 1;
2572 /* Check everything. */
2573 last_level_to_check = 0;
2575 for (parm_level = parms;
2576 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2577 parm_level = TREE_CHAIN (parm_level))
2579 tree inner_parms = TREE_VALUE (parm_level);
2583 ntparms = TREE_VEC_LENGTH (inner_parms);
2584 for (i = 0; i < ntparms; ++i)
2585 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2593 /* Clear out the default argument so that we are not
2595 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2598 /* At this point, if we're still interested in issuing messages,
2599 they must apply to classes surrounding the object declared. */
2601 msg = "default argument for template parameter for class enclosing `%D'";
2605 /* Worker for push_template_decl_real, called via
2606 for_each_template_parm. DATA is really an int, indicating the
2607 level of the parameters we are interested in. If T is a template
2608 parameter of that level, return nonzero. */
2611 template_parm_this_level_p (tree t, void* data)
2613 int this_level = *(int *)data;
2616 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2617 level = TEMPLATE_PARM_LEVEL (t);
2619 level = TEMPLATE_TYPE_LEVEL (t);
2620 return level == this_level;
2623 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2624 parameters given by current_template_args, or reuses a
2625 previously existing one, if appropriate. Returns the DECL, or an
2626 equivalent one, if it is replaced via a call to duplicate_decls.
2628 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2631 push_template_decl_real (tree decl, int is_friend)
2639 int new_template_p = 0;
2641 /* See if this is a partial specialization. */
2642 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2643 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2644 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2646 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2649 /* For a friend, we want the context of the friend function, not
2650 the type of which it is a friend. */
2651 ctx = DECL_CONTEXT (decl);
2652 else if (CP_DECL_CONTEXT (decl)
2653 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2654 /* In the case of a virtual function, we want the class in which
2656 ctx = CP_DECL_CONTEXT (decl);
2658 /* Otherwise, if we're currently defining some class, the DECL
2659 is assumed to be a member of the class. */
2660 ctx = current_scope ();
2662 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2665 if (!DECL_CONTEXT (decl))
2666 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2668 /* See if this is a primary template. */
2669 primary = template_parm_scope_p ();
2673 if (current_lang_name == lang_name_c)
2674 error ("template with C linkage");
2675 else if (TREE_CODE (decl) == TYPE_DECL
2676 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2677 error ("template class without a name");
2678 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2679 && CLASS_TYPE_P (TREE_TYPE (decl)))
2680 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx))
2681 || TREE_CODE (decl) == FUNCTION_DECL)
2684 error ("template declaration of `%#D'", decl);
2687 /* Check to see that the rules regarding the use of default
2688 arguments are not being violated. */
2689 check_default_tmpl_args (decl, current_template_parms,
2690 primary, is_partial);
2693 return process_partial_specialization (decl);
2695 args = current_template_args ();
2698 || TREE_CODE (ctx) == FUNCTION_DECL
2699 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
2700 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
2702 if (DECL_LANG_SPECIFIC (decl)
2703 && DECL_TEMPLATE_INFO (decl)
2704 && DECL_TI_TEMPLATE (decl))
2705 tmpl = DECL_TI_TEMPLATE (decl);
2706 /* If DECL is a TYPE_DECL for a class-template, then there won't
2707 be DECL_LANG_SPECIFIC. The information equivalent to
2708 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2709 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
2710 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2711 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2713 /* Since a template declaration already existed for this
2714 class-type, we must be redeclaring it here. Make sure
2715 that the redeclaration is valid. */
2716 redeclare_class_template (TREE_TYPE (decl),
2717 current_template_parms);
2718 /* We don't need to create a new TEMPLATE_DECL; just use the
2719 one we already had. */
2720 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2724 tmpl = build_template_decl (decl, current_template_parms);
2727 if (DECL_LANG_SPECIFIC (decl)
2728 && DECL_TEMPLATE_SPECIALIZATION (decl))
2730 /* A specialization of a member template of a template
2732 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2733 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
2734 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
2740 tree a, t, current, parms;
2743 if (TREE_CODE (decl) == TYPE_DECL)
2745 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
2746 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
2747 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2748 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2749 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2752 error ("`%D' does not declare a template type", decl);
2756 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
2758 error ("template definition of non-template `%#D'", decl);
2762 tmpl = DECL_TI_TEMPLATE (decl);
2764 if (is_member_template (tmpl)
2765 && DECL_FUNCTION_TEMPLATE_P (tmpl)
2766 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
2767 && DECL_TEMPLATE_SPECIALIZATION (decl))
2771 /* The declaration is a specialization of a member
2772 template, declared outside the class. Therefore, the
2773 innermost template arguments will be NULL, so we
2774 replace them with the arguments determined by the
2775 earlier call to check_explicit_specialization. */
2776 args = DECL_TI_ARGS (decl);
2779 = build_template_decl (decl, current_template_parms);
2780 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
2781 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
2782 DECL_TI_TEMPLATE (decl) = new_tmpl;
2783 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
2784 DECL_TEMPLATE_INFO (new_tmpl)
2785 = tree_cons (tmpl, args, NULL_TREE);
2787 register_specialization (new_tmpl,
2788 most_general_template (tmpl),
2793 /* Make sure the template headers we got make sense. */
2795 parms = DECL_TEMPLATE_PARMS (tmpl);
2796 i = TMPL_PARMS_DEPTH (parms);
2797 if (TMPL_ARGS_DEPTH (args) != i)
2799 error ("expected %d levels of template parms for `%#D', got %d",
2800 i, decl, TMPL_ARGS_DEPTH (args));
2803 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
2805 a = TMPL_ARGS_LEVEL (args, i);
2806 t = INNERMOST_TEMPLATE_PARMS (parms);
2808 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
2810 if (current == decl)
2811 error ("got %d template parameters for `%#D'",
2812 TREE_VEC_LENGTH (a), decl);
2814 error ("got %d template parameters for `%#T'",
2815 TREE_VEC_LENGTH (a), current);
2816 error (" but %d required", TREE_VEC_LENGTH (t));
2819 /* Perhaps we should also check that the parms are used in the
2820 appropriate qualifying scopes in the declarator? */
2822 if (current == decl)
2825 current = TYPE_CONTEXT (current);
2829 DECL_TEMPLATE_RESULT (tmpl) = decl;
2830 TREE_TYPE (tmpl) = TREE_TYPE (decl);
2832 /* Push template declarations for global functions and types. Note
2833 that we do not try to push a global template friend declared in a
2834 template class; such a thing may well depend on the template
2835 parameters of the class. */
2836 if (new_template_p && !ctx
2837 && !(is_friend && template_class_depth (current_class_type) > 0))
2838 tmpl = pushdecl_namespace_level (tmpl);
2842 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
2843 if (DECL_CONV_FN_P (tmpl))
2845 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2847 /* It is a conversion operator. See if the type converted to
2848 depends on innermost template operands. */
2850 if (for_each_template_parm (TREE_TYPE (TREE_TYPE (tmpl)),
2851 template_parm_this_level_p,
2854 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
2858 info = tree_cons (tmpl, args, NULL_TREE);
2860 if (DECL_IMPLICIT_TYPEDEF_P (decl))
2862 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
2863 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
2864 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2865 /* Don't change the name if we've already set it up. */
2866 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
2867 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
2869 else if (DECL_LANG_SPECIFIC (decl))
2870 DECL_TEMPLATE_INFO (decl) = info;
2872 return DECL_TEMPLATE_RESULT (tmpl);
2876 push_template_decl (tree decl)
2878 return push_template_decl_real (decl, 0);
2881 /* Called when a class template TYPE is redeclared with the indicated
2882 template PARMS, e.g.:
2884 template <class T> struct S;
2885 template <class T> struct S {}; */
2888 redeclare_class_template (tree type, tree parms)
2894 if (!TYPE_TEMPLATE_INFO (type))
2896 error ("`%T' is not a template type", type);
2900 tmpl = TYPE_TI_TEMPLATE (type);
2901 if (!PRIMARY_TEMPLATE_P (tmpl))
2902 /* The type is nested in some template class. Nothing to worry
2903 about here; there are no new template parameters for the nested
2907 parms = INNERMOST_TEMPLATE_PARMS (parms);
2908 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
2910 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
2912 cp_error_at ("previous declaration `%D'", tmpl);
2913 error ("used %d template parameter%s instead of %d",
2914 TREE_VEC_LENGTH (tmpl_parms),
2915 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
2916 TREE_VEC_LENGTH (parms));
2920 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
2922 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
2923 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
2924 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
2925 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
2927 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm))
2929 cp_error_at ("template parameter `%#D'", tmpl_parm);
2930 error ("redeclared here as `%#D'", parm);
2934 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
2936 /* We have in [temp.param]:
2938 A template-parameter may not be given default arguments
2939 by two different declarations in the same scope. */
2940 error ("redefinition of default argument for `%#D'", parm);
2941 error ("%H original definition appeared here",
2942 &DECL_SOURCE_LOCATION (tmpl_parm));
2946 if (parm_default != NULL_TREE)
2947 /* Update the previous template parameters (which are the ones
2948 that will really count) with the new default value. */
2949 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
2950 else if (tmpl_default != NULL_TREE)
2951 /* Update the new parameters, too; they'll be used as the
2952 parameters for any members. */
2953 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
2957 /* Attempt to convert the non-type template parameter EXPR to the
2958 indicated TYPE. If the conversion is successful, return the
2959 converted value. If the conversion is unsuccessful, return
2960 NULL_TREE if we issued an error message, or error_mark_node if we
2961 did not. We issue error messages for out-and-out bad template
2962 parameters, but not simply because the conversion failed, since we
2963 might be just trying to do argument deduction. By the time this
2964 function is called, neither TYPE nor EXPR may make use of template
2968 convert_nontype_argument (tree type, tree expr)
2970 tree expr_type = TREE_TYPE (expr);
2972 /* A template-argument for a non-type, non-template
2973 template-parameter shall be one of:
2975 --an integral constant-expression of integral or enumeration
2978 --the name of a non-type template-parameter; or
2980 --the name of an object or function with external linkage,
2981 including function templates and function template-ids but
2982 excluding non-static class members, expressed as id-expression;
2985 --the address of an object or function with external linkage,
2986 including function templates and function template-ids but
2987 excluding non-static class members, expressed as & id-expression
2988 where the & is optional if the name refers to a function or
2991 --a pointer to member expressed as described in _expr.unary.op_. */
2993 /* An integral constant-expression can include const variables or
2994 enumerators. Simplify things by folding them to their values,
2995 unless we're about to bind the declaration to a reference
2997 if (INTEGRAL_TYPE_P (expr_type)
2998 && TREE_CODE (type) != REFERENCE_TYPE)
2999 expr = decl_constant_value (expr);
3001 if (is_overloaded_fn (expr))
3002 /* OK for now. We'll check that it has external linkage later.
3003 Check this first since if expr_type is the unknown_type_node
3004 we would otherwise complain below. */
3006 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3008 if (TREE_CODE (expr) != PTRMEM_CST)
3011 else if (TYPE_PTR_P (expr_type)
3012 || TREE_CODE (expr_type) == ARRAY_TYPE
3013 || TREE_CODE (type) == REFERENCE_TYPE
3014 /* If expr is the address of an overloaded function, we
3015 will get the unknown_type_node at this point. */
3016 || expr_type == unknown_type_node)
3022 if (TREE_CODE (expr_type) == ARRAY_TYPE
3023 || (TREE_CODE (type) == REFERENCE_TYPE
3024 && TREE_CODE (e) != ADDR_EXPR))
3028 if (TREE_CODE (e) != ADDR_EXPR)
3031 error ("`%E' is not a valid template argument", expr);
3032 if (TYPE_PTR_P (expr_type))
3034 if (TREE_CODE (TREE_TYPE (expr_type)) == FUNCTION_TYPE)
3035 error ("it must be the address of a function with external linkage");
3037 error ("it must be the address of an object with external linkage");
3039 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3040 error ("it must be a pointer-to-member of the form `&X::Y'");
3045 referent = TREE_OPERAND (e, 0);
3046 STRIP_NOPS (referent);
3049 if (TREE_CODE (referent) == STRING_CST)
3051 error ("string literal %E is not a valid template argument because it is the address of an object with static linkage",
3056 if (TREE_CODE (referent) == SCOPE_REF)
3057 referent = TREE_OPERAND (referent, 1);
3059 if (is_overloaded_fn (referent))
3060 /* We'll check that it has external linkage later. */
3062 else if (TREE_CODE (referent) != VAR_DECL)
3064 else if (!DECL_EXTERNAL_LINKAGE_P (referent))
3066 error ("address of non-extern `%E' cannot be used as template argument", referent);
3067 return error_mark_node;
3070 else if (INTEGRAL_TYPE_P (expr_type) || TYPE_PTR_TO_MEMBER_P (expr_type))
3072 if (! TREE_CONSTANT (expr))
3075 error ("non-constant `%E' cannot be used as template argument",
3083 error ("type '%T' cannot be used as a value for a non-type "
3084 "template-parameter", expr);
3085 else if (DECL_P (expr))
3086 error ("invalid use of '%D' as a non-type template-argument", expr);
3088 error ("invalid use of '%E' as a non-type template-argument", expr);
3093 switch (TREE_CODE (type))
3098 /* For a non-type template-parameter of integral or enumeration
3099 type, integral promotions (_conv.prom_) and integral
3100 conversions (_conv.integral_) are applied. */
3101 if (!INTEGRAL_TYPE_P (expr_type))
3102 return error_mark_node;
3104 /* It's safe to call digest_init in this case; we know we're
3105 just converting one integral constant expression to another. */
3106 expr = digest_init (type, expr, (tree*) 0);
3108 if (TREE_CODE (expr) != INTEGER_CST)
3109 /* Curiously, some TREE_CONSTANT integral expressions do not
3110 simplify to integer constants. For example, `3 % 0',
3111 remains a TRUNC_MOD_EXPR. */
3120 /* For a non-type template-parameter of type pointer to data
3121 member, qualification conversions (_conv.qual_) are
3123 e = perform_qualification_conversions (type, expr);
3124 if (TREE_CODE (e) == NOP_EXPR)
3125 /* The call to perform_qualification_conversions will
3126 insert a NOP_EXPR over EXPR to do express conversion,
3127 if necessary. But, that will confuse us if we use
3128 this (converted) template parameter to instantiate
3129 another template; then the thing will not look like a
3130 valid template argument. So, just make a new
3131 constant, of the appropriate type. */
3132 e = make_ptrmem_cst (type, PTRMEM_CST_MEMBER (expr));
3138 tree type_pointed_to = TREE_TYPE (type);
3140 if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE)
3142 /* For a non-type template-parameter of type pointer to
3143 function, only the function-to-pointer conversion
3144 (_conv.func_) is applied. If the template-argument
3145 represents a set of overloaded functions (or a pointer to
3146 such), the matching function is selected from the set
3151 if (TREE_CODE (expr) == ADDR_EXPR)
3152 fns = TREE_OPERAND (expr, 0);
3156 fn = instantiate_type (type_pointed_to, fns, tf_none);
3158 if (fn == error_mark_node)
3159 return error_mark_node;
3161 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3163 if (really_overloaded_fn (fns))
3164 return error_mark_node;
3169 expr = build_unary_op (ADDR_EXPR, fn, 0);
3171 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3177 /* For a non-type template-parameter of type pointer to
3178 object, qualification conversions (_conv.qual_) and the
3179 array-to-pointer conversion (_conv.array_) are applied.
3180 [Note: In particular, neither the null pointer conversion
3181 (_conv.ptr_) nor the derived-to-base conversion
3182 (_conv.ptr_) are applied. Although 0 is a valid
3183 template-argument for a non-type template-parameter of
3184 integral type, it is not a valid template-argument for a
3185 non-type template-parameter of pointer type.]
3187 The call to decay_conversion performs the
3188 array-to-pointer conversion, if appropriate. */
3189 expr = decay_conversion (expr);
3191 if (expr == error_mark_node)
3192 return error_mark_node;
3194 return perform_qualification_conversions (type, expr);
3199 case REFERENCE_TYPE:
3201 tree type_referred_to = TREE_TYPE (type);
3203 /* If this expression already has reference type, get the
3204 underling object. */
3205 if (TREE_CODE (expr_type) == REFERENCE_TYPE)
3207 my_friendly_assert (TREE_CODE (expr) == ADDR_EXPR, 20000604);
3208 expr = TREE_OPERAND (expr, 0);
3209 expr_type = TREE_TYPE (expr);
3212 if (TREE_CODE (type_referred_to) == FUNCTION_TYPE)
3214 /* For a non-type template-parameter of type reference to
3215 function, no conversions apply. If the
3216 template-argument represents a set of overloaded
3217 functions, the matching function is selected from the
3218 set (_over.over_). */
3221 fn = instantiate_type (type_referred_to, expr, tf_none);
3223 if (fn == error_mark_node)
3224 return error_mark_node;
3226 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3228 if (really_overloaded_fn (expr))
3229 /* Don't issue an error here; we might get a different
3230 function if the overloading had worked out
3232 return error_mark_node;
3237 my_friendly_assert (same_type_p (type_referred_to,
3245 /* For a non-type template-parameter of type reference to
3246 object, no conversions apply. The type referred to by the
3247 reference may be more cv-qualified than the (otherwise
3248 identical) type of the template-argument. The
3249 template-parameter is bound directly to the
3250 template-argument, which must be an lvalue. */
3251 if (!same_type_p (TYPE_MAIN_VARIANT (expr_type),
3252 TYPE_MAIN_VARIANT (type_referred_to))
3253 || !at_least_as_qualified_p (type_referred_to,
3255 || !real_lvalue_p (expr))
3256 return error_mark_node;
3259 cxx_mark_addressable (expr);
3260 return build1 (ADDR_EXPR, type, expr);
3266 my_friendly_assert (TYPE_PTRMEMFUNC_P (type), 20010112);
3268 /* For a non-type template-parameter of type pointer to member
3269 function, no conversions apply. If the template-argument
3270 represents a set of overloaded member functions, the
3271 matching member function is selected from the set
3274 if (!TYPE_PTRMEMFUNC_P (expr_type) &&
3275 expr_type != unknown_type_node)
3276 return error_mark_node;
3278 if (TREE_CODE (expr) == PTRMEM_CST)
3280 /* A ptr-to-member constant. */
3281 if (!same_type_p (type, expr_type))
3282 return error_mark_node;
3287 if (TREE_CODE (expr) != ADDR_EXPR)
3288 return error_mark_node;
3290 expr = instantiate_type (type, expr, tf_none);
3292 if (expr == error_mark_node)
3293 return error_mark_node;
3295 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3302 /* All non-type parameters must have one of these types. */
3307 return error_mark_node;
3310 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3311 template template parameters. Both PARM_PARMS and ARG_PARMS are
3312 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3315 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3316 the case, then extra parameters must have default arguments.
3318 Consider the example:
3319 template <class T, class Allocator = allocator> class vector;
3320 template<template <class U> class TT> class C;
3322 C<vector> is a valid instantiation. PARM_PARMS for the above code
3323 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3324 T and Allocator) and OUTER_ARGS contains the argument that is used to
3325 substitute the TT parameter. */
3328 coerce_template_template_parms (tree parm_parms,
3330 tsubst_flags_t complain,
3334 int nparms, nargs, i;
3337 my_friendly_assert (TREE_CODE (parm_parms) == TREE_VEC, 0);
3338 my_friendly_assert (TREE_CODE (arg_parms) == TREE_VEC, 0);
3340 nparms = TREE_VEC_LENGTH (parm_parms);
3341 nargs = TREE_VEC_LENGTH (arg_parms);
3343 /* The rule here is opposite of coerce_template_parms. */
3346 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3349 for (i = 0; i < nparms; ++i)
3351 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3352 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3354 if (arg == NULL_TREE || arg == error_mark_node
3355 || parm == NULL_TREE || parm == error_mark_node)
3358 if (TREE_CODE (arg) != TREE_CODE (parm))
3361 switch (TREE_CODE (parm))
3367 /* We encounter instantiations of templates like
3368 template <template <template <class> class> class TT>
3371 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3372 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3374 if (!coerce_template_template_parms
3375 (parmparm, argparm, complain, in_decl, outer_args))
3381 /* The tsubst call is used to handle cases such as
3382 template <class T, template <T> class TT> class D;
3383 i.e. the parameter list of TT depends on earlier parameters. */
3385 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3397 /* Convert the indicated template ARG as necessary to match the
3398 indicated template PARM. Returns the converted ARG, or
3399 error_mark_node if the conversion was unsuccessful. Error and
3400 warning messages are issued under control of COMPLAIN. This
3401 conversion is for the Ith parameter in the parameter list. ARGS is
3402 the full set of template arguments deduced so far. */
3405 convert_template_argument (tree parm,
3408 tsubst_flags_t complain,
3414 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3416 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3418 if (TREE_CODE (arg) == TREE_LIST
3419 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3421 /* The template argument was the name of some
3422 member function. That's usually
3423 invalid, but static members are OK. In any
3424 case, grab the underlying fields/functions
3425 and issue an error later if required. */
3426 arg = TREE_VALUE (arg);
3427 TREE_TYPE (arg) = unknown_type_node;
3430 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3431 requires_type = (TREE_CODE (parm) == TYPE_DECL
3432 || requires_tmpl_type);
3434 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3435 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3436 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3437 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3440 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3441 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3442 arg = TYPE_STUB_DECL (arg);
3444 is_type = TYPE_P (arg) || is_tmpl_type;
3446 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3447 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3449 pedwarn ("to refer to a type member of a template parameter, use `typename %E'", arg);
3451 arg = make_typename_type (TREE_OPERAND (arg, 0),
3452 TREE_OPERAND (arg, 1),
3453 complain & tf_error);
3456 if (is_type != requires_type)
3460 if (complain & tf_error)
3462 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3465 error (" expected a constant of type `%T', got `%T'",
3467 (is_tmpl_type ? DECL_NAME (arg) : arg));
3468 else if (requires_tmpl_type)
3469 error (" expected a class template, got `%E'", arg);
3471 error (" expected a type, got `%E'", arg);
3474 return error_mark_node;
3476 if (is_tmpl_type ^ requires_tmpl_type)
3478 if (in_decl && (complain & tf_error))
3480 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3483 error (" expected a type, got `%T'", DECL_NAME (arg));
3485 error (" expected a class template, got `%T'", arg);
3487 return error_mark_node;
3492 if (requires_tmpl_type)
3494 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3495 /* The number of argument required is not known yet.
3496 Just accept it for now. */
3497 val = TREE_TYPE (arg);
3500 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3501 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3503 if (coerce_template_template_parms (parmparm, argparm,
3509 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3511 if (val != error_mark_node
3512 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3513 val = TREE_TYPE (val);
3517 if (in_decl && (complain & tf_error))
3519 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3521 error (" expected a template of type `%D', got `%D'", parm, arg);
3524 val = error_mark_node;
3529 val = groktypename (arg);
3533 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3535 if (invalid_nontype_parm_type_p (t, complain))
3536 return error_mark_node;
3538 if (!uses_template_parms (arg) && !uses_template_parms (t))
3539 /* We used to call digest_init here. However, digest_init
3540 will report errors, which we don't want when complain
3541 is zero. More importantly, digest_init will try too
3542 hard to convert things: for example, `0' should not be
3543 converted to pointer type at this point according to
3544 the standard. Accepting this is not merely an
3545 extension, since deciding whether or not these
3546 conversions can occur is part of determining which
3547 function template to call, or whether a given explicit
3548 argument specification is valid. */
3549 val = convert_nontype_argument (t, arg);
3553 if (val == NULL_TREE)
3554 val = error_mark_node;
3555 else if (val == error_mark_node && (complain & tf_error))
3556 error ("could not convert template argument `%E' to `%T'",
3563 /* Convert all template arguments to their appropriate types, and
3564 return a vector containing the innermost resulting template
3565 arguments. If any error occurs, return error_mark_node. Error and
3566 warning messages are issued under control of COMPLAIN.
3568 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3569 provided in ARGLIST, or else trailing parameters must have default
3570 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3571 deduction for any unspecified trailing arguments. */
3574 coerce_template_parms (tree parms,
3577 tsubst_flags_t complain,
3578 int require_all_arguments)
3580 int nparms, nargs, i, lost = 0;
3583 tree new_inner_args;
3585 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3586 nargs = NUM_TMPL_ARGS (inner_args);
3587 nparms = TREE_VEC_LENGTH (parms);
3591 && require_all_arguments
3592 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3594 if (complain & tf_error)
3596 error ("wrong number of template arguments (%d, should be %d)",
3600 cp_error_at ("provided for `%D'", in_decl);
3603 return error_mark_node;
3606 new_inner_args = make_tree_vec (nparms);
3607 new_args = add_outermost_template_args (args, new_inner_args);
3608 for (i = 0; i < nparms; i++)
3613 /* Get the Ith template parameter. */
3614 parm = TREE_VEC_ELT (parms, i);
3616 /* Calculate the Ith argument. */
3617 if (inner_args && TREE_CODE (inner_args) == TREE_LIST)
3619 arg = TREE_VALUE (inner_args);
3620 inner_args = TREE_CHAIN (inner_args);
3623 arg = TREE_VEC_ELT (inner_args, i);
3624 else if (require_all_arguments)
3625 /* There must be a default arg in this case. */
3626 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
3631 my_friendly_assert (arg, 20030727);
3632 if (arg == error_mark_node)
3633 error ("template argument %d is invalid", i + 1);
3635 arg = convert_template_argument (TREE_VALUE (parm),
3636 arg, new_args, complain, i,
3639 if (arg == error_mark_node)
3641 TREE_VEC_ELT (new_inner_args, i) = arg;
3645 return error_mark_node;
3647 return new_inner_args;
3650 /* Returns 1 if template args OT and NT are equivalent. */
3653 template_args_equal (tree ot, tree nt)
3658 if (TREE_CODE (nt) == TREE_VEC)
3659 /* For member templates */
3660 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
3661 else if (TYPE_P (nt))
3662 return TYPE_P (ot) && same_type_p (ot, nt);
3663 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
3666 return cp_tree_equal (ot, nt);
3669 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
3670 of template arguments. Returns 0 otherwise. */
3673 comp_template_args (tree oldargs, tree newargs)
3677 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
3680 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
3682 tree nt = TREE_VEC_ELT (newargs, i);
3683 tree ot = TREE_VEC_ELT (oldargs, i);
3685 if (! template_args_equal (ot, nt))
3691 /* Given class template name and parameter list, produce a user-friendly name
3692 for the instantiation. */
3695 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
3697 static struct obstack scratch_obstack;
3698 static char *scratch_firstobj;
3701 if (!scratch_firstobj)
3702 gcc_obstack_init (&scratch_obstack);
3704 obstack_free (&scratch_obstack, scratch_firstobj);
3705 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
3707 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
3708 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
3712 nparms = TREE_VEC_LENGTH (parms);
3713 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
3714 my_friendly_assert (nparms == TREE_VEC_LENGTH (arglist), 268);
3715 for (i = 0; i < nparms; i++)
3717 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3718 tree arg = TREE_VEC_ELT (arglist, i);
3723 if (TREE_CODE (parm) == TYPE_DECL)
3725 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
3728 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3730 if (TREE_CODE (arg) == TEMPLATE_DECL)
3732 /* Already substituted with real template. Just output
3733 the template name here */
3734 tree context = DECL_CONTEXT (arg);
3737 /* The template may be defined in a namespace, or
3738 may be a member template. */
3739 my_friendly_assert (TREE_CODE (context) == NAMESPACE_DECL
3740 || CLASS_TYPE_P (context),
3742 cat(decl_as_string (DECL_CONTEXT (arg), TFF_PLAIN_IDENTIFIER));
3745 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
3748 /* Output the parameter declaration */
3749 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
3753 my_friendly_assert (TREE_CODE (parm) == PARM_DECL, 269);
3755 if (TREE_CODE (arg) == TREE_LIST)
3757 /* New list cell was built because old chain link was in
3759 my_friendly_assert (TREE_PURPOSE (arg) == NULL_TREE, 270);
3760 arg = TREE_VALUE (arg);
3762 /* No need to check arglist against parmlist here; we did that
3763 in coerce_template_parms, called from lookup_template_class. */
3764 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
3767 char *bufp = obstack_next_free (&scratch_obstack);
3769 while (bufp[offset - 1] == ' ')
3771 obstack_blank_fast (&scratch_obstack, offset);
3773 /* B<C<char> >, not B<C<char>> */
3774 if (bufp[offset - 1] == '>')
3779 return (char *) obstack_base (&scratch_obstack);
3783 classtype_mangled_name (tree t)
3785 if (CLASSTYPE_TEMPLATE_INFO (t)
3786 /* Specializations have already had their names set up in
3787 lookup_template_class. */
3788 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
3790 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
3792 /* For non-primary templates, the template parameters are
3793 implicit from their surrounding context. */
3794 if (PRIMARY_TEMPLATE_P (tmpl))
3796 tree name = DECL_NAME (tmpl);
3797 char *mangled_name = mangle_class_name_for_template
3798 (IDENTIFIER_POINTER (name),
3799 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
3800 CLASSTYPE_TI_ARGS (t));
3801 tree id = get_identifier (mangled_name);
3802 IDENTIFIER_TEMPLATE (id) = name;
3807 return TYPE_IDENTIFIER (t);
3811 add_pending_template (tree d)
3813 tree ti = (TYPE_P (d)
3814 ? CLASSTYPE_TEMPLATE_INFO (d)
3815 : DECL_TEMPLATE_INFO (d));
3819 if (TI_PENDING_TEMPLATE_FLAG (ti))
3822 /* We are called both from instantiate_decl, where we've already had a
3823 tinst_level pushed, and instantiate_template, where we haven't.
3825 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
3828 push_tinst_level (d);
3830 pt = tree_cons (current_tinst_level, d, NULL_TREE);
3831 if (last_pending_template)
3832 TREE_CHAIN (last_pending_template) = pt;
3834 pending_templates = pt;
3836 last_pending_template = pt;
3838 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
3845 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
3846 ARGLIST. Valid choices for FNS are given in the cp-tree.def
3847 documentation for TEMPLATE_ID_EXPR. */
3850 lookup_template_function (tree fns, tree arglist)
3854 if (fns == error_mark_node || arglist == error_mark_node)
3855 return error_mark_node;
3857 if (fns == NULL_TREE)
3859 error ("non-template used as template");
3860 return error_mark_node;
3863 my_friendly_assert (TREE_CODE (fns) == TEMPLATE_DECL
3864 || TREE_CODE (fns) == OVERLOAD
3866 || TREE_CODE (fns) == IDENTIFIER_NODE,
3869 if (BASELINK_P (fns))
3871 BASELINK_FUNCTIONS (fns) = build (TEMPLATE_ID_EXPR,
3873 BASELINK_FUNCTIONS (fns),
3878 type = TREE_TYPE (fns);
3879 if (TREE_CODE (fns) == OVERLOAD || !type)
3880 type = unknown_type_node;
3882 return build (TEMPLATE_ID_EXPR, type, fns, arglist);
3885 /* Within the scope of a template class S<T>, the name S gets bound
3886 (in build_self_reference) to a TYPE_DECL for the class, not a
3887 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
3888 or one of its enclosing classes, and that type is a template,
3889 return the associated TEMPLATE_DECL. Otherwise, the original
3890 DECL is returned. */
3893 maybe_get_template_decl_from_type_decl (tree decl)
3895 return (decl != NULL_TREE
3896 && TREE_CODE (decl) == TYPE_DECL
3897 && DECL_ARTIFICIAL (decl)
3898 && CLASS_TYPE_P (TREE_TYPE (decl))
3899 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
3900 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
3903 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
3904 parameters, find the desired type.
3906 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
3907 (Actually ARGLIST may be either a TREE_LIST or a TREE_VEC. It will
3908 be a TREE_LIST if called directly from the parser, and a TREE_VEC
3911 IN_DECL, if non-NULL, is the template declaration we are trying to
3914 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
3915 the class we are looking up.
3917 Issue error and warning messages under control of COMPLAIN.
3919 If the template class is really a local class in a template
3920 function, then the FUNCTION_CONTEXT is the function in which it is
3921 being instantiated. */
3924 lookup_template_class (tree d1,
3929 tsubst_flags_t complain)
3931 tree template = NULL_TREE, parmlist;
3934 timevar_push (TV_NAME_LOOKUP);
3935 my_friendly_assert ((!arglist || TREE_CODE (arglist) == TREE_LIST)
3936 == ((complain & tf_user) != 0), 20030724);
3938 if (TREE_CODE (d1) == IDENTIFIER_NODE)
3940 if (IDENTIFIER_VALUE (d1)
3941 && DECL_TEMPLATE_TEMPLATE_PARM_P (IDENTIFIER_VALUE (d1)))
3942 template = IDENTIFIER_VALUE (d1);
3946 push_decl_namespace (context);
3947 template = lookup_name (d1, /*prefer_type=*/0);
3948 template = maybe_get_template_decl_from_type_decl (template);
3950 pop_decl_namespace ();
3953 context = DECL_CONTEXT (template);
3955 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
3957 tree type = TREE_TYPE (d1);
3959 /* If we are declaring a constructor, say A<T>::A<T>, we will get
3960 an implicit typename for the second A. Deal with it. */
3961 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
3962 type = TREE_TYPE (type);
3964 if (CLASSTYPE_TEMPLATE_INFO (type))
3966 template = CLASSTYPE_TI_TEMPLATE (type);
3967 d1 = DECL_NAME (template);
3970 else if (TREE_CODE (d1) == ENUMERAL_TYPE
3971 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
3973 template = TYPE_TI_TEMPLATE (d1);
3974 d1 = DECL_NAME (template);
3976 else if (TREE_CODE (d1) == TEMPLATE_DECL
3977 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
3980 d1 = DECL_NAME (template);
3981 context = DECL_CONTEXT (template);
3984 /* With something like `template <class T> class X class X { ... };'
3985 we could end up with D1 having nothing but an IDENTIFIER_VALUE.
3986 We don't want to do that, but we have to deal with the situation,
3987 so let's give them some syntax errors to chew on instead of a
3988 crash. Alternatively D1 might not be a template type at all. */
3991 if (complain & tf_error)
3992 error ("`%T' is not a template", d1);
3993 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
3996 if (TREE_CODE (template) != TEMPLATE_DECL
3997 /* Make sure it's a user visible template, if it was named by
3999 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4000 && !PRIMARY_TEMPLATE_P (template)))
4002 if (complain & tf_error)
4004 error ("non-template type `%T' used as a template", d1);
4006 cp_error_at ("for template declaration `%D'", in_decl);
4008 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4011 complain &= ~tf_user;
4013 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4015 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4016 template arguments */
4021 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4023 /* Consider an example where a template template parameter declared as
4025 template <class T, class U = std::allocator<T> > class TT
4027 The template parameter level of T and U are one level larger than
4028 of TT. To proper process the default argument of U, say when an
4029 instantiation `TT<int>' is seen, we need to build the full
4030 arguments containing {int} as the innermost level. Outer levels,
4031 available when not appearing as default template argument, can be
4032 obtained from `current_template_args ()'.
4034 Suppose that TT is later substituted with std::vector. The above
4035 instantiation is `TT<int, std::allocator<T> >' with TT at
4036 level 1, and T at level 2, while the template arguments at level 1
4037 becomes {std::vector} and the inner level 2 is {int}. */
4039 if (current_template_parms)
4040 arglist = add_to_template_args (current_template_args (), arglist);
4042 arglist2 = coerce_template_parms (parmlist, arglist, template,
4043 complain, /*require_all_args=*/1);
4044 if (arglist2 == error_mark_node
4045 || (!uses_template_parms (arglist2)
4046 && check_instantiated_args (template, arglist2, complain)))
4047 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4049 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4050 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4054 tree template_type = TREE_TYPE (template);
4057 tree found = NULL_TREE;
4061 int is_partial_instantiation;
4063 gen_tmpl = most_general_template (template);
4064 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4065 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4066 arg_depth = TMPL_ARGS_DEPTH (arglist);
4068 if (arg_depth == 1 && parm_depth > 1)
4070 /* We've been given an incomplete set of template arguments.
4073 template <class T> struct S1 {
4074 template <class U> struct S2 {};
4075 template <class U> struct S2<U*> {};
4078 we will be called with an ARGLIST of `U*', but the
4079 TEMPLATE will be `template <class T> template
4080 <class U> struct S1<T>::S2'. We must fill in the missing
4083 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4085 arg_depth = TMPL_ARGS_DEPTH (arglist);
4088 /* Now we should have enough arguments. */
4089 my_friendly_assert (parm_depth == arg_depth, 0);
4091 /* From here on, we're only interested in the most general
4093 template = gen_tmpl;
4095 /* Calculate the BOUND_ARGS. These will be the args that are
4096 actually tsubst'd into the definition to create the
4100 /* We have multiple levels of arguments to coerce, at once. */
4102 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4104 tree bound_args = make_tree_vec (parm_depth);
4106 for (i = saved_depth,
4107 t = DECL_TEMPLATE_PARMS (template);
4108 i > 0 && t != NULL_TREE;
4109 --i, t = TREE_CHAIN (t))
4111 tree a = coerce_template_parms (TREE_VALUE (t),
4113 complain, /*require_all_args=*/1);
4115 /* Don't process further if one of the levels fails. */
4116 if (a == error_mark_node)
4118 /* Restore the ARGLIST to its full size. */
4119 TREE_VEC_LENGTH (arglist) = saved_depth;
4120 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4123 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4125 /* We temporarily reduce the length of the ARGLIST so
4126 that coerce_template_parms will see only the arguments
4127 corresponding to the template parameters it is
4129 TREE_VEC_LENGTH (arglist)--;
4132 /* Restore the ARGLIST to its full size. */
4133 TREE_VEC_LENGTH (arglist) = saved_depth;
4135 arglist = bound_args;
4139 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4140 INNERMOST_TEMPLATE_ARGS (arglist),
4142 complain, /*require_all_args=*/1);
4144 if (arglist == error_mark_node
4145 || (!uses_template_parms (INNERMOST_TEMPLATE_ARGS (arglist))
4146 && check_instantiated_args (template,
4147 INNERMOST_TEMPLATE_ARGS (arglist),
4149 /* We were unable to bind the arguments. */
4150 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4152 /* In the scope of a template class, explicit references to the
4153 template class refer to the type of the template, not any
4154 instantiation of it. For example, in:
4156 template <class T> class C { void f(C<T>); }
4158 the `C<T>' is just the same as `C'. Outside of the
4159 class, however, such a reference is an instantiation. */
4160 if (comp_template_args (TYPE_TI_ARGS (template_type),
4163 found = template_type;
4165 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4169 for (ctx = current_class_type;
4171 ctx = TYPE_CONTEXT (ctx))
4173 if (TREE_CODE (ctx) == NAMESPACE_DECL)
4175 if (same_type_p (ctx, template_type))
4179 /* We're not in the scope of the class, so the
4180 TEMPLATE_TYPE is not the type we want after all. */
4186 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4188 for (tp = &DECL_TEMPLATE_INSTANTIATIONS (template);
4190 tp = &TREE_CHAIN (*tp))
4191 if (comp_template_args (TREE_PURPOSE (*tp), arglist))
4195 /* Use the move-to-front heuristic to speed up future
4197 *tp = TREE_CHAIN (*tp);
4199 = DECL_TEMPLATE_INSTANTIATIONS (template);
4200 DECL_TEMPLATE_INSTANTIATIONS (template) = found;
4202 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, TREE_VALUE (found));
4205 /* This type is a "partial instantiation" if any of the template
4206 arguments still involve template parameters. Note that we set
4207 IS_PARTIAL_INSTANTIATION for partial specializations as
4209 is_partial_instantiation = uses_template_parms (arglist);
4211 if (!is_partial_instantiation
4212 && !PRIMARY_TEMPLATE_P (template)
4213 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4215 found = xref_tag_from_type (TREE_TYPE (template),
4216 DECL_NAME (template),
4218 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4221 context = tsubst (DECL_CONTEXT (template), arglist,
4224 context = global_namespace;
4226 /* Create the type. */
4227 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4229 if (!is_partial_instantiation)
4231 set_current_access_from_decl (TYPE_NAME (template_type));
4232 t = start_enum (TYPE_IDENTIFIER (template_type));
4235 /* We don't want to call start_enum for this type, since
4236 the values for the enumeration constants may involve
4237 template parameters. And, no one should be interested
4238 in the enumeration constants for such a type. */
4239 t = make_node (ENUMERAL_TYPE);
4243 t = make_aggr_type (TREE_CODE (template_type));
4244 CLASSTYPE_DECLARED_CLASS (t)
4245 = CLASSTYPE_DECLARED_CLASS (template_type);
4246 CLASSTYPE_GOT_SEMICOLON (t) = 1;
4247 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4248 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4250 /* A local class. Make sure the decl gets registered properly. */
4251 if (context == current_function_decl)
4252 pushtag (DECL_NAME (template), t, 0);
4255 /* If we called start_enum or pushtag above, this information
4256 will already be set up. */
4259 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4261 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4262 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4263 TYPE_STUB_DECL (t) = type_decl;
4264 DECL_SOURCE_LOCATION (type_decl)
4265 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4268 type_decl = TYPE_NAME (t);
4270 TREE_PRIVATE (type_decl)
4271 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4272 TREE_PROTECTED (type_decl)
4273 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4275 /* Set up the template information. We have to figure out which
4276 template is the immediate parent if this is a full
4278 if (parm_depth == 1 || is_partial_instantiation
4279 || !PRIMARY_TEMPLATE_P (template))
4280 /* This case is easy; there are no member templates involved. */
4284 /* This is a full instantiation of a member template. Look
4285 for a partial instantiation of which this is an instance. */
4287 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4288 found; found = TREE_CHAIN (found))
4291 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4293 /* We only want partial instantiations, here, not
4294 specializations or full instantiations. */
4295 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4296 || !uses_template_parms (TREE_VALUE (found)))
4299 /* Temporarily reduce by one the number of levels in the
4300 ARGLIST and in FOUND so as to avoid comparing the
4301 last set of arguments. */
4302 TREE_VEC_LENGTH (arglist)--;
4303 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4305 /* See if the arguments match. If they do, then TMPL is
4306 the partial instantiation we want. */
4307 success = comp_template_args (TREE_PURPOSE (found), arglist);
4309 /* Restore the argument vectors to their full size. */
4310 TREE_VEC_LENGTH (arglist)++;
4311 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4322 /* There was no partial instantiation. This happens
4323 where C<T> is a member template of A<T> and it's used
4326 template <typename T> struct B { A<T>::C<int> m; };
4329 Create the partial instantiation.
4331 TREE_VEC_LENGTH (arglist)--;
4332 found = tsubst (template, arglist, complain, NULL_TREE);
4333 TREE_VEC_LENGTH (arglist)++;
4337 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4338 DECL_TEMPLATE_INSTANTIATIONS (template)
4339 = tree_cons (arglist, t,
4340 DECL_TEMPLATE_INSTANTIATIONS (template));
4342 if (TREE_CODE (t) == ENUMERAL_TYPE
4343 && !is_partial_instantiation)
4344 /* Now that the type has been registered on the instantiations
4345 list, we set up the enumerators. Because the enumeration
4346 constants may involve the enumeration type itself, we make
4347 sure to register the type first, and then create the
4348 constants. That way, doing tsubst_expr for the enumeration
4349 constants won't result in recursive calls here; we'll find
4350 the instantiation and exit above. */
4351 tsubst_enum (template_type, t, arglist);
4353 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4355 if (TREE_CODE (t) != ENUMERAL_TYPE)
4356 DECL_NAME (type_decl) = classtype_mangled_name (t);
4357 if (!is_partial_instantiation)
4359 /* For backwards compatibility; code that uses
4360 -fexternal-templates expects looking up a template to
4361 instantiate it. I think DDD still relies on this.
4362 (jason 8/20/1998) */
4363 if (TREE_CODE (t) != ENUMERAL_TYPE
4364 && flag_external_templates
4365 && CLASSTYPE_INTERFACE_KNOWN (TREE_TYPE (template))
4366 && ! CLASSTYPE_INTERFACE_ONLY (TREE_TYPE (template)))
4367 add_pending_template (t);
4370 /* If the type makes use of template parameters, the
4371 code that generates debugging information will crash. */
4372 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4374 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4376 timevar_pop (TV_NAME_LOOKUP);
4386 /* Called from for_each_template_parm via walk_tree. */
4389 for_each_template_parm_r (tree* tp, int* walk_subtrees, void* d)
4392 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4393 tree_fn_t fn = pfd->fn;
4394 void *data = pfd->data;
4397 /* If we have already visited this tree, there's no need to walk
4398 subtrees. Otherwise, add it to the visited table. */
4399 slot = htab_find_slot (pfd->visited, *tp, INSERT);
4408 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4409 return error_mark_node;
4411 switch (TREE_CODE (t))
4414 if (TYPE_PTRMEMFUNC_P (t))
4420 if (!TYPE_TEMPLATE_INFO (t))
4422 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4423 fn, data, pfd->visited))
4424 return error_mark_node;
4428 /* Since we're not going to walk subtrees, we have to do this
4430 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4432 return error_mark_node;
4436 /* Check the return type. */
4437 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4438 return error_mark_node;
4440 /* Check the parameter types. Since default arguments are not
4441 instantiated until they are needed, the TYPE_ARG_TYPES may
4442 contain expressions that involve template parameters. But,
4443 no-one should be looking at them yet. And, once they're
4444 instantiated, they don't contain template parameters, so
4445 there's no point in looking at them then, either. */
4449 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4450 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4452 return error_mark_node;
4454 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4455 want walk_tree walking into them itself. */
4461 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4463 return error_mark_node;
4468 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4469 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4471 return error_mark_node;
4476 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4477 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4479 return error_mark_node;
4480 if (DECL_CONTEXT (t)
4481 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4483 return error_mark_node;
4486 case BOUND_TEMPLATE_TEMPLATE_PARM:
4487 /* Record template parameters such as `T' inside `TT<T>'. */
4488 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4489 return error_mark_node;
4492 case TEMPLATE_TEMPLATE_PARM:
4493 case TEMPLATE_TYPE_PARM:
4494 case TEMPLATE_PARM_INDEX:
4495 if (fn && (*fn)(t, data))
4496 return error_mark_node;
4498 return error_mark_node;
4502 /* A template template parameter is encountered */
4503 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4504 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4505 return error_mark_node;
4507 /* Already substituted template template parameter */
4513 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4514 data, pfd->visited))
4515 return error_mark_node;
4519 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4520 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4521 (TREE_TYPE (t)), fn, data,
4523 return error_mark_node;
4528 /* If there's no type, then this thing must be some expression
4529 involving template parameters. */
4530 if (!fn && !TREE_TYPE (t))
4531 return error_mark_node;
4536 case REINTERPRET_CAST_EXPR:
4537 case CONST_CAST_EXPR:
4538 case STATIC_CAST_EXPR:
4539 case DYNAMIC_CAST_EXPR:
4543 case PSEUDO_DTOR_EXPR:
4545 return error_mark_node;
4549 /* If we do not handle this case specially, we end up walking
4550 the BINFO hierarchy, which is circular, and therefore
4551 confuses walk_tree. */
4553 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4555 return error_mark_node;
4562 /* We didn't find any template parameters we liked. */
4566 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4567 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4568 call FN with the parameter and the DATA.
4569 If FN returns nonzero, the iteration is terminated, and
4570 for_each_template_parm returns 1. Otherwise, the iteration
4571 continues. If FN never returns a nonzero value, the value
4572 returned by for_each_template_parm is 0. If FN is NULL, it is
4573 considered to be the function which always returns 1. */
4576 for_each_template_parm (tree t, tree_fn_t fn, void* data, htab_t visited)
4578 struct pair_fn_data pfd;
4585 /* Walk the tree. (Conceptually, we would like to walk without
4586 duplicates, but for_each_template_parm_r recursively calls
4587 for_each_template_parm, so we would need to reorganize a fair
4588 bit to use walk_tree_without_duplicates, so we keep our own
4591 pfd.visited = visited;
4593 pfd.visited = htab_create (37, htab_hash_pointer, htab_eq_pointer,
4595 result = walk_tree (&t,
4596 for_each_template_parm_r,
4602 htab_delete (pfd.visited);
4608 uses_template_parms (tree t)
4610 return for_each_template_parm (t, 0, 0, NULL);
4613 static int tinst_depth;
4614 extern int max_tinst_depth;
4615 #ifdef GATHER_STATISTICS
4618 static int tinst_level_tick;
4619 static int last_template_error_tick;
4621 /* We're starting to instantiate D; record the template instantiation context
4622 for diagnostics and to restore it later. */
4625 push_tinst_level (tree d)
4629 if (tinst_depth >= max_tinst_depth)
4631 /* If the instantiation in question still has unbound template parms,
4632 we don't really care if we can't instantiate it, so just return.
4633 This happens with base instantiation for implicit `typename'. */
4634 if (uses_template_parms (d))
4637 last_template_error_tick = tinst_level_tick;
4638 error ("template instantiation depth exceeds maximum of %d (use -ftemplate-depth-NN to increase the maximum) instantiating `%D'",
4639 max_tinst_depth, d);
4641 print_instantiation_context ();
4646 new = build_expr_wfl (d, input_filename, input_line, 0);
4647 TREE_CHAIN (new) = current_tinst_level;
4648 current_tinst_level = new;
4651 #ifdef GATHER_STATISTICS
4652 if (tinst_depth > depth_reached)
4653 depth_reached = tinst_depth;
4660 /* We're done instantiating this template; return to the instantiation
4664 pop_tinst_level (void)
4666 tree old = current_tinst_level;
4668 /* Restore the filename and line number stashed away when we started
4669 this instantiation. */
4670 input_line = TINST_LINE (old);
4671 input_filename = TINST_FILE (old);
4672 extract_interface_info ();
4674 current_tinst_level = TREE_CHAIN (old);
4679 /* We're instantiating a deferred template; restore the template
4680 instantiation context in which the instantiation was requested, which
4681 is one step out from LEVEL. */
4684 reopen_tinst_level (tree level)
4689 for (t = level; t; t = TREE_CHAIN (t))
4692 current_tinst_level = level;
4696 /* Return the outermost template instantiation context, for use with
4697 -falt-external-templates. */
4700 tinst_for_decl (void)
4702 tree p = current_tinst_level;
4705 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
4710 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4711 vector of template arguments, as for tsubst.
4713 Returns an appropriate tsubst'd friend declaration. */
4716 tsubst_friend_function (tree decl, tree args)
4719 location_t saved_loc = input_location;
4721 input_location = DECL_SOURCE_LOCATION (decl);
4723 if (TREE_CODE (decl) == FUNCTION_DECL
4724 && DECL_TEMPLATE_INSTANTIATION (decl)
4725 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
4726 /* This was a friend declared with an explicit template
4727 argument list, e.g.:
4731 to indicate that f was a template instantiation, not a new
4732 function declaration. Now, we have to figure out what
4733 instantiation of what template. */
4735 tree template_id, arglist, fns;
4738 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
4740 /* Friend functions are looked up in the containing namespace scope.
4741 We must enter that scope, to avoid finding member functions of the
4742 current cless with same name. */
4743 push_nested_namespace (ns);
4744 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
4745 tf_error | tf_warning, NULL_TREE);
4746 pop_nested_namespace (ns);
4747 arglist = tsubst (DECL_TI_ARGS (decl), args,
4748 tf_error | tf_warning, NULL_TREE);
4749 template_id = lookup_template_function (fns, arglist);
4751 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
4752 tmpl = determine_specialization (template_id, new_friend,
4754 /*need_member_template=*/0);
4755 new_friend = instantiate_template (tmpl, new_args, tf_error);
4759 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
4761 /* The NEW_FRIEND will look like an instantiation, to the
4762 compiler, but is not an instantiation from the point of view of
4763 the language. For example, we might have had:
4765 template <class T> struct S {
4766 template <class U> friend void f(T, U);
4769 Then, in S<int>, template <class U> void f(int, U) is not an
4770 instantiation of anything. */
4771 DECL_USE_TEMPLATE (new_friend) = 0;
4772 if (TREE_CODE (decl) == TEMPLATE_DECL)
4774 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
4775 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
4776 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
4779 /* The mangled name for the NEW_FRIEND is incorrect. The function
4780 is not a template instantiation and should not be mangled like
4781 one. Therefore, we forget the mangling here; we'll recompute it
4782 later if we need it. */
4783 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
4785 SET_DECL_RTL (new_friend, NULL_RTX);
4786 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
4789 if (DECL_NAMESPACE_SCOPE_P (new_friend))
4792 tree new_friend_template_info;
4793 tree new_friend_result_template_info;
4795 int new_friend_is_defn;
4797 /* We must save some information from NEW_FRIEND before calling
4798 duplicate decls since that function will free NEW_FRIEND if
4800 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
4801 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
4803 /* This declaration is a `primary' template. */
4804 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
4807 = DECL_INITIAL (DECL_TEMPLATE_RESULT (new_friend)) != NULL_TREE;
4808 new_friend_result_template_info
4809 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
4813 new_friend_is_defn = DECL_INITIAL (new_friend) != NULL_TREE;
4814 new_friend_result_template_info = NULL_TREE;
4817 /* Inside pushdecl_namespace_level, we will push into the
4818 current namespace. However, the friend function should go
4819 into the namespace of the template. */
4820 ns = decl_namespace_context (new_friend);
4821 push_nested_namespace (ns);
4822 old_decl = pushdecl_namespace_level (new_friend);
4823 pop_nested_namespace (ns);
4825 if (old_decl != new_friend)
4827 /* This new friend declaration matched an existing
4828 declaration. For example, given:
4830 template <class T> void f(T);
4831 template <class U> class C {
4832 template <class T> friend void f(T) {}
4835 the friend declaration actually provides the definition
4836 of `f', once C has been instantiated for some type. So,
4837 old_decl will be the out-of-class template declaration,
4838 while new_friend is the in-class definition.
4840 But, if `f' was called before this point, the
4841 instantiation of `f' will have DECL_TI_ARGS corresponding
4842 to `T' but not to `U', references to which might appear
4843 in the definition of `f'. Previously, the most general
4844 template for an instantiation of `f' was the out-of-class
4845 version; now it is the in-class version. Therefore, we
4846 run through all specialization of `f', adding to their
4847 DECL_TI_ARGS appropriately. In particular, they need a
4848 new set of outer arguments, corresponding to the
4849 arguments for this class instantiation.
4851 The same situation can arise with something like this:
4854 template <class T> class C {
4858 when `C<int>' is instantiated. Now, `f(int)' is defined
4861 if (!new_friend_is_defn)
4862 /* On the other hand, if the in-class declaration does
4863 *not* provide a definition, then we don't want to alter
4864 existing definitions. We can just leave everything
4869 /* Overwrite whatever template info was there before, if
4870 any, with the new template information pertaining to
4872 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
4874 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
4875 reregister_specialization (new_friend,
4876 most_general_template (old_decl),
4881 tree new_friend_args;
4883 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
4884 = new_friend_result_template_info;
4886 new_friend_args = TI_ARGS (new_friend_template_info);
4887 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
4891 tree spec = TREE_VALUE (t);
4894 = add_outermost_template_args (new_friend_args,
4895 DECL_TI_ARGS (spec));
4898 /* Now, since specializations are always supposed to
4899 hang off of the most general template, we must move
4901 t = most_general_template (old_decl);
4904 DECL_TEMPLATE_SPECIALIZATIONS (t)
4905 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
4906 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
4907 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
4912 /* The information from NEW_FRIEND has been merged into OLD_DECL
4913 by duplicate_decls. */
4914 new_friend = old_decl;
4917 else if (COMPLETE_TYPE_P (DECL_CONTEXT (new_friend)))
4919 /* Check to see that the declaration is really present, and,
4920 possibly obtain an improved declaration. */
4921 tree fn = check_classfn (DECL_CONTEXT (new_friend),
4929 input_location = saved_loc;
4933 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
4934 template arguments, as for tsubst.
4936 Returns an appropriate tsubst'd friend type or error_mark_node on
4940 tsubst_friend_class (tree friend_tmpl, tree args)
4946 context = DECL_CONTEXT (friend_tmpl);
4950 if (TREE_CODE (context) == NAMESPACE_DECL)
4951 push_nested_namespace (context);
4953 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
4956 /* First, we look for a class template. */
4957 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
4959 /* But, if we don't find one, it might be because we're in a
4960 situation like this:
4968 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
4969 for `S<int>', not the TEMPLATE_DECL. */
4970 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
4972 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
4973 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
4976 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
4978 /* The friend template has already been declared. Just
4979 check to see that the declarations match, and install any new
4980 default parameters. We must tsubst the default parameters,
4981 of course. We only need the innermost template parameters
4982 because that is all that redeclare_class_template will look
4984 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
4985 > TMPL_ARGS_DEPTH (args))
4988 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
4989 args, tf_error | tf_warning);
4990 redeclare_class_template (TREE_TYPE (tmpl), parms);
4993 friend_type = TREE_TYPE (tmpl);
4997 /* The friend template has not already been declared. In this
4998 case, the instantiation of the template class will cause the
4999 injection of this template into the global scope. */
5000 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5002 /* The new TMPL is not an instantiation of anything, so we
5003 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5004 the new type because that is supposed to be the corresponding
5005 template decl, i.e., TMPL. */
5006 DECL_USE_TEMPLATE (tmpl) = 0;
5007 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5008 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5010 /* Inject this template into the global scope. */
5011 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5016 if (TREE_CODE (context) == NAMESPACE_DECL)
5017 pop_nested_namespace (context);
5019 pop_nested_class ();
5025 /* Returns zero if TYPE cannot be completed later due to circularity.
5026 Otherwise returns one. */
5029 can_complete_type_without_circularity (tree type)
5031 if (type == NULL_TREE || type == error_mark_node)
5033 else if (COMPLETE_TYPE_P (type))
5035 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5036 return can_complete_type_without_circularity (TREE_TYPE (type));
5037 else if (CLASS_TYPE_P (type)
5038 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5045 instantiate_class_template (tree type)
5047 tree template, args, pattern, t, member;
5051 if (type == error_mark_node)
5052 return error_mark_node;
5054 if (TYPE_BEING_DEFINED (type)
5055 || COMPLETE_TYPE_P (type)
5056 || dependent_type_p (type))
5059 /* Figure out which template is being instantiated. */
5060 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5061 my_friendly_assert (TREE_CODE (template) == TEMPLATE_DECL, 279);
5063 /* Figure out which arguments are being used to do the
5065 args = CLASSTYPE_TI_ARGS (type);
5067 /* Determine what specialization of the original template to
5069 t = most_specialized_class (template, args);
5070 if (t == error_mark_node)
5072 const char *str = "candidates are:";
5073 error ("ambiguous class template instantiation for `%#T'", type);
5074 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5077 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5079 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5083 TYPE_BEING_DEFINED (type) = 1;
5084 return error_mark_node;
5088 pattern = TREE_TYPE (t);
5090 pattern = TREE_TYPE (template);
5092 /* If the template we're instantiating is incomplete, then clearly
5093 there's nothing we can do. */
5094 if (!COMPLETE_TYPE_P (pattern))
5097 /* If we've recursively instantiated too many templates, stop. */
5098 if (! push_tinst_level (type))
5101 /* Now we're really doing the instantiation. Mark the type as in
5102 the process of being defined. */
5103 TYPE_BEING_DEFINED (type) = 1;
5105 /* We may be in the middle of deferred access check. Disable
5107 push_deferring_access_checks (dk_no_deferred);
5109 maybe_push_to_top_level (uses_template_parms (type));
5113 /* This TYPE is actually an instantiation of a partial
5114 specialization. We replace the innermost set of ARGS with
5115 the arguments appropriate for substitution. For example,
5118 template <class T> struct S {};
5119 template <class T> struct S<T*> {};
5121 and supposing that we are instantiating S<int*>, ARGS will
5122 present be {int*} but we need {int}. */
5124 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5127 /* If there were multiple levels in ARGS, replacing the
5128 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5129 want, so we make a copy first. */
5130 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5132 args = copy_node (args);
5133 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5139 if (flag_external_templates)
5141 if (flag_alt_external_templates)
5143 CLASSTYPE_INTERFACE_ONLY (type) = interface_only;
5144 SET_CLASSTYPE_INTERFACE_UNKNOWN_X (type, interface_unknown);
5148 CLASSTYPE_INTERFACE_ONLY (type) = CLASSTYPE_INTERFACE_ONLY (pattern);
5149 SET_CLASSTYPE_INTERFACE_UNKNOWN_X
5150 (type, CLASSTYPE_INTERFACE_UNKNOWN (pattern));
5155 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5158 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5159 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5160 TYPE_OVERLOADS_CALL_EXPR (type) = TYPE_OVERLOADS_CALL_EXPR (pattern);
5161 TYPE_OVERLOADS_ARRAY_REF (type) = TYPE_OVERLOADS_ARRAY_REF (pattern);
5162 TYPE_OVERLOADS_ARROW (type) = TYPE_OVERLOADS_ARROW (pattern);
5163 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5164 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5165 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5166 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5167 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5168 TYPE_HAS_ABSTRACT_ASSIGN_REF (type) = TYPE_HAS_ABSTRACT_ASSIGN_REF (pattern);
5169 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5170 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5171 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5172 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5173 TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
5174 = TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (pattern);
5175 TYPE_USES_MULTIPLE_INHERITANCE (type)
5176 = TYPE_USES_MULTIPLE_INHERITANCE (pattern);
5177 TYPE_USES_VIRTUAL_BASECLASSES (type)
5178 = TYPE_USES_VIRTUAL_BASECLASSES (pattern);
5179 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5180 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5181 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5182 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5183 if (ANON_AGGR_TYPE_P (pattern))
5184 SET_ANON_AGGR_TYPE_P (type);
5186 pbinfo = TYPE_BINFO (pattern);
5188 if (BINFO_BASETYPES (pbinfo))
5190 tree base_list = NULL_TREE;
5191 tree pbases = BINFO_BASETYPES (pbinfo);
5192 tree paccesses = BINFO_BASEACCESSES (pbinfo);
5195 /* Substitute into each of the bases to determine the actual
5197 for (i = 0; i < TREE_VEC_LENGTH (pbases); ++i)
5203 pbase = TREE_VEC_ELT (pbases, i);
5204 access = TREE_VEC_ELT (paccesses, i);
5206 /* Substitute to figure out the base class. */
5207 base = tsubst (BINFO_TYPE (pbase), args, tf_error, NULL_TREE);
5208 if (base == error_mark_node)
5211 base_list = tree_cons (access, base, base_list);
5212 TREE_VIA_VIRTUAL (base_list) = TREE_VIA_VIRTUAL (pbase);
5215 /* The list is now in reverse order; correct that. */
5216 base_list = nreverse (base_list);
5218 /* Now call xref_basetypes to set up all the base-class
5220 xref_basetypes (type, base_list);
5223 /* Now that our base classes are set up, enter the scope of the
5224 class, so that name lookups into base classes, etc. will work
5225 correctly. This is precisely analogous to what we do in
5226 begin_class_definition when defining an ordinary non-template
5230 /* Now members are processed in the order of declaration. */
5231 for (member = CLASSTYPE_DECL_LIST (pattern);
5232 member; member = TREE_CHAIN (member))
5234 tree t = TREE_VALUE (member);
5236 if (TREE_PURPOSE (member))
5240 /* Build new CLASSTYPE_NESTED_UTDS. */
5243 tree name = TYPE_IDENTIFIER (tag);
5246 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5247 my_friendly_assert (newtag != error_mark_node, 20010206);
5248 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5250 if (TYPE_LANG_SPECIFIC (tag) && CLASSTYPE_IS_TEMPLATE (tag))
5251 /* Unfortunately, lookup_template_class sets
5252 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5253 instantiation (i.e., for the type of a member template
5254 class nested within a template class.) This behavior is
5255 required for maybe_process_partial_specialization to work
5256 correctly, but is not accurate in this case; the TAG is not
5257 an instantiation of anything. (The corresponding
5258 TEMPLATE_DECL is an instantiation, but the TYPE is not.) */
5259 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5261 /* Now, we call pushtag to put this NEWTAG into the scope of
5262 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5263 pushtag calling push_template_decl. We don't have to do
5264 this for enums because it will already have been done in
5267 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5268 pushtag (name, newtag, /*globalize=*/0);
5271 else if (TREE_CODE (t) == FUNCTION_DECL
5272 || DECL_FUNCTION_TEMPLATE_P (t))
5274 /* Build new TYPE_METHODS. */
5276 tree r = tsubst (t, args, tf_error, NULL_TREE);
5277 set_current_access_from_decl (r);
5278 grok_special_member_properties (r);
5279 finish_member_declaration (r);
5283 /* Build new TYPE_FIELDS. */
5285 if (TREE_CODE (t) != CONST_DECL)
5289 /* The the file and line for this declaration, to
5290 assist in error message reporting. Since we
5291 called push_tinst_level above, we don't need to
5293 input_location = DECL_SOURCE_LOCATION (t);
5295 if (TREE_CODE (t) == TEMPLATE_DECL)
5296 processing_template_decl++;
5297 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5298 if (TREE_CODE (t) == TEMPLATE_DECL)
5299 processing_template_decl--;
5300 if (TREE_CODE (r) == VAR_DECL)
5304 if (DECL_INITIALIZED_IN_CLASS_P (r))
5305 init = tsubst_expr (DECL_INITIAL (t), args,
5306 tf_error | tf_warning, NULL_TREE);
5310 finish_static_data_member_decl
5311 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5313 if (DECL_INITIALIZED_IN_CLASS_P (r))
5314 check_static_variable_definition (r, TREE_TYPE (r));
5316 else if (TREE_CODE (r) == FIELD_DECL)
5318 /* Determine whether R has a valid type and can be
5319 completed later. If R is invalid, then it is
5320 replaced by error_mark_node so that it will not be
5321 added to TYPE_FIELDS. */
5322 tree rtype = TREE_TYPE (r);
5323 if (can_complete_type_without_circularity (rtype))
5324 complete_type (rtype);
5326 if (!COMPLETE_TYPE_P (rtype))
5328 cxx_incomplete_type_error (r, rtype);
5329 r = error_mark_node;
5333 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5334 such a thing will already have been added to the field
5335 list by tsubst_enum in finish_member_declaration in the
5336 CLASSTYPE_NESTED_UTDS case above. */
5337 if (!(TREE_CODE (r) == TYPE_DECL
5338 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5339 && DECL_ARTIFICIAL (r)))
5341 set_current_access_from_decl (r);
5342 finish_member_declaration (r);
5349 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5351 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5353 tree friend_type = t;
5354 tree new_friend_type;
5356 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5357 new_friend_type = tsubst_friend_class (friend_type, args);
5358 else if (uses_template_parms (friend_type))
5359 new_friend_type = tsubst (friend_type, args,
5360 tf_error | tf_warning, NULL_TREE);
5361 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5362 new_friend_type = friend_type;
5365 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5367 /* The call to xref_tag_from_type does injection for friend
5369 push_nested_namespace (ns);
5371 xref_tag_from_type (friend_type, NULL_TREE, 1);
5372 pop_nested_namespace (ns);
5375 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5376 /* Trick make_friend_class into realizing that the friend
5377 we're adding is a template, not an ordinary class. It's
5378 important that we use make_friend_class since it will
5379 perform some error-checking and output cross-reference
5381 ++processing_template_decl;
5383 if (new_friend_type != error_mark_node)
5384 make_friend_class (type, new_friend_type);
5386 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5387 --processing_template_decl;
5390 /* Build new DECL_FRIENDLIST. */
5391 add_friend (type, tsubst_friend_function (t, args));
5395 /* Set the file and line number information to whatever is given for
5396 the class itself. This puts error messages involving generated
5397 implicit functions at a predictable point, and the same point
5398 that would be used for non-template classes. */
5399 typedecl = TYPE_MAIN_DECL (type);
5400 input_location = DECL_SOURCE_LOCATION (typedecl);
5402 unreverse_member_declarations (type);
5403 finish_struct_1 (type);
5404 CLASSTYPE_GOT_SEMICOLON (type) = 1;
5406 /* Clear this now so repo_template_used is happy. */
5407 TYPE_BEING_DEFINED (type) = 0;
5408 repo_template_used (type);
5410 /* Now that the class is complete, instantiate default arguments for
5411 any member functions. We don't do this earlier because the
5412 default arguments may reference members of the class. */
5413 if (!PRIMARY_TEMPLATE_P (template))
5414 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5415 if (TREE_CODE (t) == FUNCTION_DECL
5416 /* Implicitly generated member functions will not have template
5417 information; they are not instantiations, but instead are
5418 created "fresh" for each instantiation. */
5419 && DECL_TEMPLATE_INFO (t))
5420 tsubst_default_arguments (t);
5423 pop_from_top_level ();
5424 pop_deferring_access_checks ();
5427 if (TYPE_CONTAINS_VPTR_P (type))
5428 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5434 list_eq (tree t1, tree t2)
5436 if (t1 == NULL_TREE)
5437 return t2 == NULL_TREE;
5438 if (t2 == NULL_TREE)
5440 /* Don't care if one declares its arg const and the other doesn't -- the
5441 main variant of the arg type is all that matters. */
5442 if (TYPE_MAIN_VARIANT (TREE_VALUE (t1))
5443 != TYPE_MAIN_VARIANT (TREE_VALUE (t2)))
5445 return list_eq (TREE_CHAIN (t1), TREE_CHAIN (t2));
5449 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5455 else if (TYPE_P (t))
5456 r = tsubst (t, args, complain, in_decl);
5459 r = tsubst_expr (t, args, complain, in_decl);
5461 if (!uses_template_parms (r))
5463 /* Sometimes, one of the args was an expression involving a
5464 template constant parameter, like N - 1. Now that we've
5465 tsubst'd, we might have something like 2 - 1. This will
5466 confuse lookup_template_class, so we do constant folding
5467 here. We have to unset processing_template_decl, to fool
5468 tsubst_copy_and_build() into building an actual tree. */
5470 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5471 as simple as it's going to get, and trying to reprocess
5472 the trees will break. Once tsubst_expr et al DTRT for
5473 non-dependent exprs, this code can go away, as the type
5474 will always be set. */
5477 int saved_processing_template_decl = processing_template_decl;
5478 processing_template_decl = 0;
5479 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5480 tf_error, /*in_decl=*/NULL_TREE,
5481 /*function_p=*/false);
5482 processing_template_decl = saved_processing_template_decl;
5490 /* Substitute ARGS into the vector or list of template arguments T. */
5493 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5495 int is_list = !(t && TREE_CODE (t) == TREE_VEC);
5496 int len = is_list ? list_length (t) : TREE_VEC_LENGTH (t);
5497 int need_new = 0, i;
5499 tree *elts = alloca (len * sizeof (tree));
5501 for (i = 0; i < len; i++)
5504 tree new_arg = NULL_TREE;
5508 orig_arg = TREE_VALUE (position);
5509 position = TREE_CHAIN (position);
5513 orig_arg = TREE_VEC_ELT (t, i);
5514 if (TREE_CODE (orig_arg) == TREE_VEC)
5515 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5519 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5521 if (new_arg == error_mark_node)
5522 return error_mark_node;
5525 if (new_arg != orig_arg)
5537 t = tree_cons (NULL_TREE, elts[i], t);
5541 t = make_tree_vec (len);
5542 for (i = 0; i < len; i++)
5543 TREE_VEC_ELT (t, i) = elts[i];
5549 /* Return the result of substituting ARGS into the template parameters
5550 given by PARMS. If there are m levels of ARGS and m + n levels of
5551 PARMS, then the result will contain n levels of PARMS. For
5552 example, if PARMS is `template <class T> template <class U>
5553 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5554 result will be `template <int*, double, class V>'. */
5557 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5562 for (new_parms = &r;
5563 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5564 new_parms = &(TREE_CHAIN (*new_parms)),
5565 parms = TREE_CHAIN (parms))
5568 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5571 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5573 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5574 tree default_value = TREE_PURPOSE (tuple);
5575 tree parm_decl = TREE_VALUE (tuple);
5577 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5578 default_value = tsubst_template_arg (default_value, args,
5579 complain, NULL_TREE);
5581 tuple = build_tree_list (default_value, parm_decl);
5582 TREE_VEC_ELT (new_vec, i) = tuple;
5586 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
5587 - TMPL_ARGS_DEPTH (args)),
5588 new_vec, NULL_TREE);
5594 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5595 type T. If T is not an aggregate or enumeration type, it is
5596 handled as if by tsubst. IN_DECL is as for tsubst. If
5597 ENTERING_SCOPE is nonzero, T is the context for a template which
5598 we are presently tsubst'ing. Return the substituted value. */
5601 tsubst_aggr_type (tree t,
5603 tsubst_flags_t complain,
5610 switch (TREE_CODE (t))
5613 if (TYPE_PTRMEMFUNC_P (t))
5614 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
5616 /* else fall through */
5619 if (TYPE_TEMPLATE_INFO (t))
5625 /* First, determine the context for the type we are looking
5627 if (TYPE_CONTEXT (t) != NULL_TREE)
5628 context = tsubst_aggr_type (TYPE_CONTEXT (t), args,
5630 in_decl, /*entering_scope=*/1);
5632 context = NULL_TREE;
5634 /* Then, figure out what arguments are appropriate for the
5635 type we are trying to find. For example, given:
5637 template <class T> struct S;
5638 template <class T, class U> void f(T, U) { S<U> su; }
5640 and supposing that we are instantiating f<int, double>,
5641 then our ARGS will be {int, double}, but, when looking up
5642 S we only want {double}. */
5643 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
5645 if (argvec == error_mark_node)
5646 return error_mark_node;
5648 r = lookup_template_class (t, argvec, in_decl, context,
5649 entering_scope, complain);
5651 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
5654 /* This is not a template type, so there's nothing to do. */
5658 return tsubst (t, args, complain, in_decl);
5662 /* Substitute into the default argument ARG (a default argument for
5663 FN), which has the indicated TYPE. */
5666 tsubst_default_argument (tree fn, tree type, tree arg)
5668 /* This default argument came from a template. Instantiate the
5669 default argument here, not in tsubst. In the case of
5678 we must be careful to do name lookup in the scope of S<T>,
5679 rather than in the current class.
5681 ??? current_class_type affects a lot more than name lookup. This is
5682 very fragile. Fortunately, it will go away when we do 2-phase name
5683 binding properly. */
5685 /* FN is already the desired FUNCTION_DECL. */
5686 push_access_scope (fn);
5688 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
5689 tf_error | tf_warning, NULL_TREE);
5691 pop_access_scope (fn);
5693 /* Make sure the default argument is reasonable. */
5694 arg = check_default_argument (type, arg);
5699 /* Substitute into all the default arguments for FN. */
5702 tsubst_default_arguments (tree fn)
5707 tmpl_args = DECL_TI_ARGS (fn);
5709 /* If this function is not yet instantiated, we certainly don't need
5710 its default arguments. */
5711 if (uses_template_parms (tmpl_args))
5714 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
5716 arg = TREE_CHAIN (arg))
5717 if (TREE_PURPOSE (arg))
5718 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
5720 TREE_PURPOSE (arg));
5723 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
5724 (already computed) substitution of ARGS into TREE_TYPE (T), if
5725 appropriate. Return the result of the substitution. Issue error
5726 and warning messages under control of COMPLAIN. */
5729 tsubst_decl (tree t, tree args, tree type, tsubst_flags_t complain)
5731 location_t saved_loc;
5735 /* Set the filename and linenumber to improve error-reporting. */
5736 saved_loc = input_location;
5737 input_location = DECL_SOURCE_LOCATION (t);
5739 switch (TREE_CODE (t))
5743 /* We can get here when processing a member template function
5744 of a template class. */
5745 tree decl = DECL_TEMPLATE_RESULT (t);
5747 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
5749 if (!is_template_template_parm)
5751 /* We might already have an instance of this template.
5752 The ARGS are for the surrounding class type, so the
5753 full args contain the tsubst'd args for the context,
5754 plus the innermost args from the template decl. */
5755 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
5756 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
5757 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
5760 full_args = tsubst_template_args (tmpl_args, args,
5763 /* tsubst_template_args doesn't copy the vector if
5764 nothing changed. But, *something* should have
5766 my_friendly_assert (full_args != tmpl_args, 0);
5768 spec = retrieve_specialization (t, full_args);
5769 if (spec != NULL_TREE)
5776 /* Make a new template decl. It will be similar to the
5777 original, but will record the current template arguments.
5778 We also create a new function declaration, which is just
5779 like the old one, but points to this new template, rather
5780 than the old one. */
5782 my_friendly_assert (DECL_LANG_SPECIFIC (r) != 0, 0);
5783 TREE_CHAIN (r) = NULL_TREE;
5785 if (is_template_template_parm)
5787 tree new_decl = tsubst (decl, args, complain, in_decl);
5788 DECL_TEMPLATE_RESULT (r) = new_decl;
5789 TREE_TYPE (r) = TREE_TYPE (new_decl);
5794 = tsubst_aggr_type (DECL_CONTEXT (t), args,
5796 /*entering_scope=*/1);
5797 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
5799 if (TREE_CODE (decl) == TYPE_DECL)
5801 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
5802 TREE_TYPE (r) = new_type;
5803 CLASSTYPE_TI_TEMPLATE (new_type) = r;
5804 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
5805 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
5809 tree new_decl = tsubst (decl, args, complain, in_decl);
5810 if (new_decl == error_mark_node)
5811 return error_mark_node;
5813 DECL_TEMPLATE_RESULT (r) = new_decl;
5814 DECL_TI_TEMPLATE (new_decl) = r;
5815 TREE_TYPE (r) = TREE_TYPE (new_decl);
5816 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
5819 SET_DECL_IMPLICIT_INSTANTIATION (r);
5820 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
5821 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
5823 /* The template parameters for this new template are all the
5824 template parameters for the old template, except the
5825 outermost level of parameters. */
5826 DECL_TEMPLATE_PARMS (r)
5827 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
5830 if (PRIMARY_TEMPLATE_P (t))
5831 DECL_PRIMARY_TEMPLATE (r) = r;
5833 if (TREE_CODE (decl) != TYPE_DECL)
5834 /* Record this non-type partial instantiation. */
5835 register_specialization (r, t,
5836 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
5843 tree argvec = NULL_TREE;
5850 /* Nobody should be tsubst'ing into non-template functions. */
5851 my_friendly_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE, 0);
5853 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
5858 /* If T is not dependent, just return it. We have to
5859 increment PROCESSING_TEMPLATE_DECL because
5860 value_dependent_expression_p assumes that nothing is
5861 dependent when PROCESSING_TEMPLATE_DECL is zero. */
5862 ++processing_template_decl;
5863 dependent_p = value_dependent_expression_p (t);
5864 --processing_template_decl;
5868 /* Calculate the most general template of which R is a
5869 specialization, and the complete set of arguments used to
5871 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
5872 argvec = tsubst_template_args (DECL_TI_ARGS
5873 (DECL_TEMPLATE_RESULT (gen_tmpl)),
5874 args, complain, in_decl);
5876 /* Check to see if we already have this specialization. */
5877 spec = retrieve_specialization (gen_tmpl, argvec);
5885 /* We can see more levels of arguments than parameters if
5886 there was a specialization of a member template, like
5889 template <class T> struct S { template <class U> void f(); }
5890 template <> template <class U> void S<int>::f(U);
5892 Here, we'll be substituting into the specialization,
5893 because that's where we can find the code we actually
5894 want to generate, but we'll have enough arguments for
5895 the most general template.
5897 We also deal with the peculiar case:
5899 template <class T> struct S {
5900 template <class U> friend void f();
5902 template <class U> void f() {}
5904 template void f<double>();
5906 Here, the ARGS for the instantiation of will be {int,
5907 double}. But, we only need as many ARGS as there are
5908 levels of template parameters in CODE_PATTERN. We are
5909 careful not to get fooled into reducing the ARGS in
5912 template <class T> struct S { template <class U> void f(U); }
5913 template <class T> template <> void S<T>::f(int) {}
5915 which we can spot because the pattern will be a
5916 specialization in this case. */
5917 args_depth = TMPL_ARGS_DEPTH (args);
5919 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
5920 if (args_depth > parms_depth
5921 && !DECL_TEMPLATE_SPECIALIZATION (t))
5922 args = get_innermost_template_args (args, parms_depth);
5926 /* This special case arises when we have something like this:
5928 template <class T> struct S {
5929 friend void f<int>(int, double);
5932 Here, the DECL_TI_TEMPLATE for the friend declaration
5933 will be an IDENTIFIER_NODE. We are being called from
5934 tsubst_friend_function, and we want only to create a
5935 new decl (R) with appropriate types so that we can call
5936 determine_specialization. */
5937 gen_tmpl = NULL_TREE;
5940 if (DECL_CLASS_SCOPE_P (t))
5942 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
5946 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
5947 complain, t, /*entering_scope=*/1);
5952 ctx = DECL_CONTEXT (t);
5954 type = tsubst (type, args, complain, in_decl);
5955 if (type == error_mark_node)
5956 return error_mark_node;
5958 /* We do NOT check for matching decls pushed separately at this
5959 point, as they may not represent instantiations of this
5960 template, and in any case are considered separate under the
5963 DECL_USE_TEMPLATE (r) = 0;
5964 TREE_TYPE (r) = type;
5965 /* Clear out the mangled name and RTL for the instantiation. */
5966 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
5967 SET_DECL_RTL (r, NULL_RTX);
5969 DECL_CONTEXT (r) = ctx;
5971 if (member && DECL_CONV_FN_P (r))
5972 /* Type-conversion operator. Reconstruct the name, in
5973 case it's the name of one of the template's parameters. */
5974 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
5976 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
5978 DECL_RESULT (r) = NULL_TREE;
5980 TREE_STATIC (r) = 0;
5981 TREE_PUBLIC (r) = TREE_PUBLIC (t);
5982 DECL_EXTERNAL (r) = 1;
5983 DECL_INTERFACE_KNOWN (r) = 0;
5984 DECL_DEFER_OUTPUT (r) = 0;
5985 TREE_CHAIN (r) = NULL_TREE;
5986 DECL_PENDING_INLINE_INFO (r) = 0;
5987 DECL_PENDING_INLINE_P (r) = 0;
5988 DECL_SAVED_TREE (r) = NULL_TREE;
5990 if (DECL_CLONED_FUNCTION (r))
5992 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
5994 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
5995 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
5998 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
5999 this in the special friend case mentioned above where
6000 GEN_TMPL is NULL. */
6003 DECL_TEMPLATE_INFO (r)
6004 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6005 SET_DECL_IMPLICIT_INSTANTIATION (r);
6006 register_specialization (r, gen_tmpl, argvec);
6008 /* We're not supposed to instantiate default arguments
6009 until they are called, for a template. But, for a
6012 template <class T> void f ()
6013 { extern void g(int i = T()); }
6015 we should do the substitution when the template is
6016 instantiated. We handle the member function case in
6017 instantiate_class_template since the default arguments
6018 might refer to other members of the class. */
6020 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6021 && !uses_template_parms (argvec))
6022 tsubst_default_arguments (r);
6025 /* Copy the list of befriending classes. */
6026 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6028 friends = &TREE_CHAIN (*friends))
6030 *friends = copy_node (*friends);
6031 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6036 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6038 maybe_retrofit_in_chrg (r);
6039 if (DECL_CONSTRUCTOR_P (r))
6040 grok_ctor_properties (ctx, r);
6041 /* If this is an instantiation of a member template, clone it.
6042 If it isn't, that'll be handled by
6043 clone_constructors_and_destructors. */
6044 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6045 clone_function_decl (r, /*update_method_vec_p=*/0);
6047 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6048 grok_op_properties (r, DECL_FRIEND_P (r));
6055 if (DECL_TEMPLATE_PARM_P (t))
6056 SET_DECL_TEMPLATE_PARM_P (r);
6058 TREE_TYPE (r) = type;
6059 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6061 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6062 DECL_INITIAL (r) = TREE_TYPE (r);
6064 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6067 DECL_CONTEXT (r) = NULL_TREE;
6069 if (!DECL_TEMPLATE_PARM_P (r))
6070 DECL_ARG_TYPE (r) = type_passed_as (type);
6072 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6073 complain, TREE_CHAIN (t));
6080 TREE_TYPE (r) = type;
6081 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6083 /* We don't have to set DECL_CONTEXT here; it is set by
6084 finish_member_declaration. */
6085 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6087 TREE_CHAIN (r) = NULL_TREE;
6088 if (VOID_TYPE_P (type))
6089 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6096 /* It is not a dependent using decl any more. */
6097 TREE_TYPE (r) = void_type_node;
6099 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6100 TREE_CHAIN (r) = NULL_TREE;
6105 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6106 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6108 /* If this is the canonical decl, we don't have to mess with
6109 instantiations, and often we can't (for typename, template
6110 type parms and such). Note that TYPE_NAME is not correct for
6111 the above test if we've copied the type for a typedef. */
6112 r = TYPE_NAME (type);
6120 tree argvec = NULL_TREE;
6121 tree gen_tmpl = NULL_TREE;
6123 tree tmpl = NULL_TREE;
6127 /* Assume this is a non-local variable. */
6130 if (TYPE_P (CP_DECL_CONTEXT (t)))
6131 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6133 in_decl, /*entering_scope=*/1);
6134 else if (DECL_NAMESPACE_SCOPE_P (t))
6135 ctx = DECL_CONTEXT (t);
6138 /* Subsequent calls to pushdecl will fill this in. */
6143 /* Check to see if we already have this specialization. */
6146 tmpl = DECL_TI_TEMPLATE (t);
6147 gen_tmpl = most_general_template (tmpl);
6148 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6149 spec = retrieve_specialization (gen_tmpl, argvec);
6152 spec = retrieve_local_specialization (t);
6161 if (TREE_CODE (r) == VAR_DECL)
6163 type = complete_type (type);
6164 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6165 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6167 else if (DECL_SELF_REFERENCE_P (t))
6168 SET_DECL_SELF_REFERENCE_P (r);
6169 TREE_TYPE (r) = type;
6170 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6171 DECL_CONTEXT (r) = ctx;
6172 /* Clear out the mangled name and RTL for the instantiation. */
6173 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6174 SET_DECL_RTL (r, NULL_RTX);
6176 /* Don't try to expand the initializer until someone tries to use
6177 this variable; otherwise we run into circular dependencies. */
6178 DECL_INITIAL (r) = NULL_TREE;
6179 SET_DECL_RTL (r, NULL_RTX);
6180 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6182 /* Even if the original location is out of scope, the newly
6183 substituted one is not. */
6184 if (TREE_CODE (r) == VAR_DECL)
6186 DECL_DEAD_FOR_LOCAL (r) = 0;
6187 DECL_INITIALIZED_P (r) = 0;
6192 /* A static data member declaration is always marked
6193 external when it is declared in-class, even if an
6194 initializer is present. We mimic the non-template
6196 DECL_EXTERNAL (r) = 1;
6198 register_specialization (r, gen_tmpl, argvec);
6199 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6200 SET_DECL_IMPLICIT_INSTANTIATION (r);
6203 register_local_specialization (r, t);
6205 TREE_CHAIN (r) = NULL_TREE;
6206 if (TREE_CODE (r) == VAR_DECL && VOID_TYPE_P (type))
6207 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6208 /* Compute the size, alignment, etc. of R. */
6217 /* Restore the file and line information. */
6218 input_location = saved_loc;
6223 /* Substitute into the ARG_TYPES of a function type. */
6226 tsubst_arg_types (tree arg_types,
6228 tsubst_flags_t complain,
6231 tree remaining_arg_types;
6234 if (!arg_types || arg_types == void_list_node)
6237 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6238 args, complain, in_decl);
6239 if (remaining_arg_types == error_mark_node)
6240 return error_mark_node;
6242 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6243 if (type == error_mark_node)
6244 return error_mark_node;
6245 if (VOID_TYPE_P (type))
6247 if (complain & tf_error)
6249 error ("invalid parameter type `%T'", type);
6251 cp_error_at ("in declaration `%D'", in_decl);
6253 return error_mark_node;
6256 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6257 top-level qualifiers as required. */
6258 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6260 /* Note that we do not substitute into default arguments here. The
6261 standard mandates that they be instantiated only when needed,
6262 which is done in build_over_call. */
6263 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6264 remaining_arg_types);
6268 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6269 *not* handle the exception-specification for FNTYPE, because the
6270 initial substitution of explicitly provided template parameters
6271 during argument deduction forbids substitution into the
6272 exception-specification:
6276 All references in the function type of the function template to the
6277 corresponding template parameters are replaced by the specified tem-
6278 plate argument values. If a substitution in a template parameter or
6279 in the function type of the function template results in an invalid
6280 type, type deduction fails. [Note: The equivalent substitution in
6281 exception specifications is done only when the function is instanti-
6282 ated, at which point a program is ill-formed if the substitution
6283 results in an invalid type.] */
6286 tsubst_function_type (tree t,
6288 tsubst_flags_t complain,
6295 /* The TYPE_CONTEXT is not used for function/method types. */
6296 my_friendly_assert (TYPE_CONTEXT (t) == NULL_TREE, 0);
6298 /* Substitute the return type. */
6299 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6300 if (return_type == error_mark_node)
6301 return error_mark_node;
6303 /* Substitute the argument types. */
6304 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6306 if (arg_types == error_mark_node)
6307 return error_mark_node;
6309 /* Construct a new type node and return it. */
6310 if (TREE_CODE (t) == FUNCTION_TYPE)
6311 fntype = build_function_type (return_type, arg_types);
6314 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6315 if (! IS_AGGR_TYPE (r))
6319 Type deduction may fail for any of the following
6322 -- Attempting to create "pointer to member of T" when T
6323 is not a class type. */
6324 if (complain & tf_error)
6325 error ("creating pointer to member function of non-class type `%T'",
6327 return error_mark_node;
6330 fntype = build_cplus_method_type (r, return_type, TREE_CHAIN
6333 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6334 fntype = build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6339 /* Substitute into the PARMS of a call-declarator. */
6342 tsubst_call_declarator_parms (tree parms,
6344 tsubst_flags_t complain,
6351 if (!parms || parms == void_list_node)
6354 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6355 args, complain, in_decl);
6357 /* Figure out the type of this parameter. */
6358 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6360 /* Figure out the default argument as well. Note that we use
6361 tsubst_expr since the default argument is really an expression. */
6362 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6364 /* Chain this parameter on to the front of those we have already
6365 processed. We don't use hash_tree_cons because that function
6366 doesn't check TREE_PARMLIST. */
6367 new_parms = tree_cons (defarg, type, new_parms);
6369 /* And note that these are parameters. */
6370 TREE_PARMLIST (new_parms) = 1;
6375 /* Take the tree structure T and replace template parameters used
6376 therein with the argument vector ARGS. IN_DECL is an associated
6377 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6378 Issue error and warning messages under control of COMPLAIN. Note
6379 that we must be relatively non-tolerant of extensions here, in
6380 order to preserve conformance; if we allow substitutions that
6381 should not be allowed, we may allow argument deductions that should
6382 not succeed, and therefore report ambiguous overload situations
6383 where there are none. In theory, we could allow the substitution,
6384 but indicate that it should have failed, and allow our caller to
6385 make sure that the right thing happens, but we don't try to do this
6388 This function is used for dealing with types, decls and the like;
6389 for expressions, use tsubst_expr or tsubst_copy. */
6392 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6396 if (t == NULL_TREE || t == error_mark_node
6397 || t == integer_type_node
6398 || t == void_type_node
6399 || t == char_type_node
6400 || TREE_CODE (t) == NAMESPACE_DECL)
6403 if (TREE_CODE (t) == IDENTIFIER_NODE)
6404 type = IDENTIFIER_TYPE_VALUE (t);
6406 type = TREE_TYPE (t);
6408 my_friendly_assert (type != unknown_type_node, 20030716);
6410 if (type && TREE_CODE (t) != FUNCTION_DECL
6411 && TREE_CODE (t) != TYPENAME_TYPE
6412 && TREE_CODE (t) != TEMPLATE_DECL
6413 && TREE_CODE (t) != IDENTIFIER_NODE
6414 && TREE_CODE (t) != FUNCTION_TYPE
6415 && TREE_CODE (t) != METHOD_TYPE)
6416 type = tsubst (type, args, complain, in_decl);
6417 if (type == error_mark_node)
6418 return error_mark_node;
6421 return tsubst_decl (t, args, type, complain);
6423 switch (TREE_CODE (t))
6428 return tsubst_aggr_type (t, args, complain, in_decl,
6429 /*entering_scope=*/0);
6432 case IDENTIFIER_NODE:
6444 if (t == integer_type_node)
6447 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6448 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6452 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6454 /* The array dimension behaves like a non-type template arg,
6455 in that we want to fold it as much as possible. */
6456 max = tsubst_template_arg (omax, args, complain, in_decl);
6457 if (!processing_template_decl)
6458 max = decl_constant_value (max);
6460 if (processing_template_decl
6461 /* When providing explicit arguments to a template
6462 function, but leaving some arguments for subsequent
6463 deduction, MAX may be template-dependent even if we're
6464 not PROCESSING_TEMPLATE_DECL. We still need to check for
6465 template parms, though; MAX won't be an INTEGER_CST for
6466 dynamic arrays, either. */
6467 || (TREE_CODE (max) != INTEGER_CST
6468 && uses_template_parms (max)))
6470 tree itype = make_node (INTEGER_TYPE);
6471 TYPE_MIN_VALUE (itype) = size_zero_node;
6472 TYPE_MAX_VALUE (itype) = build_min (MINUS_EXPR, sizetype, max,
6477 if (integer_zerop (omax))
6479 /* Still allow an explicit array of size zero. */
6481 pedwarn ("creating array with size zero");
6483 else if (integer_zerop (max)
6484 || (TREE_CODE (max) == INTEGER_CST
6485 && INT_CST_LT (max, integer_zero_node)))
6489 Type deduction may fail for any of the following
6492 Attempting to create an array with a size that is
6493 zero or negative. */
6494 if (complain & tf_error)
6495 error ("creating array with size zero (`%E')", max);
6497 return error_mark_node;
6500 return compute_array_index_type (NULL_TREE, max);
6503 case TEMPLATE_TYPE_PARM:
6504 case TEMPLATE_TEMPLATE_PARM:
6505 case BOUND_TEMPLATE_TEMPLATE_PARM:
6506 case TEMPLATE_PARM_INDEX:
6514 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6515 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6516 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6518 idx = TEMPLATE_TYPE_IDX (t);
6519 level = TEMPLATE_TYPE_LEVEL (t);
6523 idx = TEMPLATE_PARM_IDX (t);
6524 level = TEMPLATE_PARM_LEVEL (t);
6527 if (TREE_VEC_LENGTH (args) > 0)
6529 tree arg = NULL_TREE;
6531 levels = TMPL_ARGS_DEPTH (args);
6532 if (level <= levels)
6533 arg = TMPL_ARG (args, level, idx);
6535 if (arg == error_mark_node)
6536 return error_mark_node;
6537 else if (arg != NULL_TREE)
6539 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6541 my_friendly_assert (TYPE_P (arg), 0);
6542 return cp_build_qualified_type_real
6543 (arg, cp_type_quals (arg) | cp_type_quals (t),
6544 complain | tf_ignore_bad_quals);
6546 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6548 /* We are processing a type constructed from
6549 a template template parameter */
6550 tree argvec = tsubst (TYPE_TI_ARGS (t),
6551 args, complain, in_decl);
6552 if (argvec == error_mark_node)
6553 return error_mark_node;
6555 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6556 we are resolving nested-types in the signature of
6557 a member function templates.
6558 Otherwise ARG is a TEMPLATE_DECL and is the real
6559 template to be instantiated. */
6560 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
6561 arg = TYPE_NAME (arg);
6563 r = lookup_template_class (arg,
6566 /*entering_scope=*/0,
6568 return cp_build_qualified_type_real
6569 (r, TYPE_QUALS (t), complain);
6572 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
6580 /* This can happen during the attempted tsubst'ing in
6581 unify. This means that we don't yet have any information
6582 about the template parameter in question. */
6585 /* If we get here, we must have been looking at a parm for a
6586 more deeply nested template. Make a new version of this
6587 template parameter, but with a lower level. */
6588 switch (TREE_CODE (t))
6590 case TEMPLATE_TYPE_PARM:
6591 case TEMPLATE_TEMPLATE_PARM:
6592 case BOUND_TEMPLATE_TEMPLATE_PARM:
6593 if (cp_type_quals (t))
6595 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
6596 r = cp_build_qualified_type_real
6597 (r, cp_type_quals (t),
6598 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6599 ? tf_ignore_bad_quals : 0));
6604 TEMPLATE_TYPE_PARM_INDEX (r)
6605 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
6607 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
6608 TYPE_MAIN_VARIANT (r) = r;
6609 TYPE_POINTER_TO (r) = NULL_TREE;
6610 TYPE_REFERENCE_TO (r) = NULL_TREE;
6612 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6614 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
6616 if (argvec == error_mark_node)
6617 return error_mark_node;
6619 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
6620 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
6625 case TEMPLATE_PARM_INDEX:
6626 r = reduce_template_parm_level (t, type, levels);
6638 tree purpose, value, chain, result;
6640 if (t == void_list_node)
6643 purpose = TREE_PURPOSE (t);
6646 purpose = tsubst (purpose, args, complain, in_decl);
6647 if (purpose == error_mark_node)
6648 return error_mark_node;
6650 value = TREE_VALUE (t);
6653 value = tsubst (value, args, complain, in_decl);
6654 if (value == error_mark_node)
6655 return error_mark_node;
6657 chain = TREE_CHAIN (t);
6658 if (chain && chain != void_type_node)
6660 chain = tsubst (chain, args, complain, in_decl);
6661 if (chain == error_mark_node)
6662 return error_mark_node;
6664 if (purpose == TREE_PURPOSE (t)
6665 && value == TREE_VALUE (t)
6666 && chain == TREE_CHAIN (t))
6668 if (TREE_PARMLIST (t))
6670 result = tree_cons (purpose, value, chain);
6671 TREE_PARMLIST (result) = 1;
6674 result = hash_tree_cons (purpose, value, chain);
6678 if (type != NULL_TREE)
6680 /* A binfo node. We always need to make a copy, of the node
6681 itself and of its BINFO_BASETYPES. */
6685 /* Make sure type isn't a typedef copy. */
6686 type = BINFO_TYPE (TYPE_BINFO (type));
6688 TREE_TYPE (t) = complete_type (type);
6689 if (IS_AGGR_TYPE (type))
6691 BINFO_VTABLE (t) = TYPE_BINFO_VTABLE (type);
6692 BINFO_VIRTUALS (t) = TYPE_BINFO_VIRTUALS (type);
6693 if (TYPE_BINFO_BASETYPES (type) != NULL_TREE)
6694 BINFO_BASETYPES (t) = copy_node (TYPE_BINFO_BASETYPES (type));
6699 /* Otherwise, a vector of template arguments. */
6700 return tsubst_template_args (t, args, complain, in_decl);
6703 case REFERENCE_TYPE:
6705 enum tree_code code;
6707 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
6710 code = TREE_CODE (t);
6715 Type deduction may fail for any of the following
6718 -- Attempting to create a pointer to reference type.
6719 -- Attempting to create a reference to a reference type or
6720 a reference to void. */
6721 if (TREE_CODE (type) == REFERENCE_TYPE
6722 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
6724 static location_t last_loc;
6726 /* We keep track of the last time we issued this error
6727 message to avoid spewing a ton of messages during a
6728 single bad template instantiation. */
6729 if (complain & tf_error
6730 && (last_loc.line != input_line
6731 || last_loc.file != input_filename))
6733 if (TREE_CODE (type) == VOID_TYPE)
6734 error ("forming reference to void");
6736 error ("forming %s to reference type `%T'",
6737 (code == POINTER_TYPE) ? "pointer" : "reference",
6739 last_loc = input_location;
6742 return error_mark_node;
6744 else if (code == POINTER_TYPE)
6746 r = build_pointer_type (type);
6747 if (TREE_CODE (type) == METHOD_TYPE)
6748 r = build_ptrmemfunc_type (r);
6751 r = build_reference_type (type);
6752 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6754 if (r != error_mark_node)
6755 /* Will this ever be needed for TYPE_..._TO values? */
6762 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
6763 if (r == error_mark_node || !IS_AGGR_TYPE (r))
6767 Type deduction may fail for any of the following
6770 -- Attempting to create "pointer to member of T" when T
6771 is not a class type. */
6772 if (complain & tf_error)
6773 error ("creating pointer to member of non-class type `%T'", r);
6774 return error_mark_node;
6776 if (TREE_CODE (type) == REFERENCE_TYPE)
6778 if (complain & tf_error)
6779 error ("creating pointer to member reference type `%T'", type);
6781 return error_mark_node;
6783 my_friendly_assert (TREE_CODE (type) != METHOD_TYPE, 20011231);
6784 if (TREE_CODE (type) == FUNCTION_TYPE)
6786 /* This is really a method type. The cv qualifiers of the
6787 this pointer should _not_ be determined by the cv
6788 qualifiers of the class type. They should be held
6789 somewhere in the FUNCTION_TYPE, but we don't do that at
6790 the moment. Consider
6791 typedef void (Func) () const;
6793 template <typename T1> void Foo (Func T1::*);
6798 method_type = build_cplus_method_type (TYPE_MAIN_VARIANT (r),
6800 TYPE_ARG_TYPES (type));
6801 return build_ptrmemfunc_type (build_pointer_type (method_type));
6804 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
6814 fntype = tsubst_function_type (t, args, complain, in_decl);
6815 if (fntype == error_mark_node)
6816 return error_mark_node;
6818 /* Substitute the exception specification. */
6819 raises = TYPE_RAISES_EXCEPTIONS (t);
6822 tree list = NULL_TREE;
6824 if (! TREE_VALUE (raises))
6827 for (; raises != NULL_TREE; raises = TREE_CHAIN (raises))
6829 tree spec = TREE_VALUE (raises);
6831 spec = tsubst (spec, args, complain, in_decl);
6832 if (spec == error_mark_node)
6834 list = add_exception_specifier (list, spec, complain);
6836 fntype = build_exception_variant (fntype, list);
6842 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
6843 if (domain == error_mark_node)
6844 return error_mark_node;
6846 /* As an optimization, we avoid regenerating the array type if
6847 it will obviously be the same as T. */
6848 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
6851 /* These checks should match the ones in grokdeclarator.
6855 The deduction may fail for any of the following reasons:
6857 -- Attempting to create an array with an element type that
6858 is void, a function type, or a reference type. */
6859 if (TREE_CODE (type) == VOID_TYPE
6860 || TREE_CODE (type) == FUNCTION_TYPE
6861 || TREE_CODE (type) == REFERENCE_TYPE)
6863 if (complain & tf_error)
6864 error ("creating array of `%T'", type);
6865 return error_mark_node;
6868 r = build_cplus_array_type (type, domain);
6875 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6876 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
6878 if (e1 == error_mark_node || e2 == error_mark_node)
6879 return error_mark_node;
6881 return fold (build (TREE_CODE (t), TREE_TYPE (t), e1, e2));
6887 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6888 if (e == error_mark_node)
6889 return error_mark_node;
6891 return fold (build (TREE_CODE (t), TREE_TYPE (t), e));
6896 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
6897 in_decl, /*entering_scope=*/1);
6898 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
6901 if (ctx == error_mark_node || f == error_mark_node)
6902 return error_mark_node;
6904 if (!IS_AGGR_TYPE (ctx))
6906 if (complain & tf_error)
6907 error ("`%T' is not a class, struct, or union type",
6909 return error_mark_node;
6911 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
6913 /* Normally, make_typename_type does not require that the CTX
6914 have complete type in order to allow things like:
6916 template <class T> struct S { typename S<T>::X Y; };
6918 But, such constructs have already been resolved by this
6919 point, so here CTX really should have complete type, unless
6920 it's a partial instantiation. */
6921 ctx = complete_type (ctx);
6922 if (!COMPLETE_TYPE_P (ctx))
6924 if (complain & tf_error)
6925 cxx_incomplete_type_error (NULL_TREE, ctx);
6926 return error_mark_node;
6930 f = make_typename_type (ctx, f,
6931 (complain & tf_error) | tf_keep_type_decl);
6932 if (f == error_mark_node)
6934 if (TREE_CODE (f) == TYPE_DECL)
6936 complain |= tf_ignore_bad_quals;
6940 return cp_build_qualified_type_real
6941 (f, cp_type_quals (f) | cp_type_quals (t), complain);
6944 case UNBOUND_CLASS_TEMPLATE:
6946 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
6947 in_decl, /*entering_scope=*/1);
6948 tree name = TYPE_IDENTIFIER (t);
6950 if (ctx == error_mark_node || name == error_mark_node)
6951 return error_mark_node;
6953 return make_unbound_class_template (ctx, name, complain);
6958 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6959 if (e == error_mark_node)
6960 return error_mark_node;
6961 return make_pointer_declarator (type, e);
6966 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6967 if (e == error_mark_node)
6968 return error_mark_node;
6969 return make_reference_declarator (type, e);
6974 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6975 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
6976 if (e1 == error_mark_node || e2 == error_mark_node)
6977 return error_mark_node;
6979 return build_nt (ARRAY_REF, e1, e2, tsubst_expr);
6984 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6985 tree e2 = (tsubst_call_declarator_parms
6986 (CALL_DECLARATOR_PARMS (t), args, complain, in_decl));
6987 tree e3 = tsubst (CALL_DECLARATOR_EXCEPTION_SPEC (t), args,
6990 if (e1 == error_mark_node || e2 == error_mark_node
6991 || e3 == error_mark_node)
6992 return error_mark_node;
6994 return make_call_declarator (e1, e2, CALL_DECLARATOR_QUALS (t), e3);
6999 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7000 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7001 if (e1 == error_mark_node || e2 == error_mark_node)
7002 return error_mark_node;
7004 return build_nt (TREE_CODE (t), e1, e2);
7009 tree e1 = tsubst_expr (TYPE_FIELDS (t), args, complain, in_decl);
7010 if (e1 == error_mark_node)
7011 return error_mark_node;
7013 return cp_build_qualified_type_real (TREE_TYPE (e1),
7015 | cp_type_quals (TREE_TYPE (e1)),
7020 sorry ("use of `%s' in template",
7021 tree_code_name [(int) TREE_CODE (t)]);
7022 return error_mark_node;
7026 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7027 type of the expression on the left-hand side of the "." or "->"
7031 tsubst_baselink (tree baselink, tree object_type,
7032 tree args, tsubst_flags_t complain, tree in_decl)
7035 tree qualifying_scope;
7037 tree template_args = 0;
7038 bool template_id_p = false;
7040 /* A baselink indicates a function from a base class. The
7041 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7042 non-dependent types; otherwise, the lookup could not have
7043 succeeded. However, they may indicate bases of the template
7044 class, rather than the instantiated class.
7046 In addition, lookups that were not ambiguous before may be
7047 ambiguous now. Therefore, we perform the lookup again. */
7048 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7049 fns = BASELINK_FUNCTIONS (baselink);
7050 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7052 template_id_p = true;
7053 template_args = TREE_OPERAND (fns, 1);
7054 fns = TREE_OPERAND (fns, 0);
7055 template_args = tsubst_copy_and_build (template_args, args,
7057 /*function_p=*/false);
7059 name = DECL_NAME (get_first_fn (fns));
7060 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7061 if (BASELINK_P (baselink) && template_id_p)
7062 BASELINK_FUNCTIONS (baselink)
7063 = build_nt (TEMPLATE_ID_EXPR,
7064 BASELINK_FUNCTIONS (baselink),
7067 object_type = current_class_type;
7068 return adjust_result_of_qualified_name_lookup (baselink,
7073 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7074 true if the qualified-id will be a postfix-expression in-and-of
7075 itself; false if more of the postfix-expression follows the
7076 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7080 tsubst_qualified_id (tree qualified_id, tree args,
7081 tsubst_flags_t complain, tree in_decl,
7082 bool done, bool address_p)
7090 my_friendly_assert (TREE_CODE (qualified_id) == SCOPE_REF, 20030706);
7092 /* Figure out what name to look up. */
7093 name = TREE_OPERAND (qualified_id, 1);
7094 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7097 template_args = tsubst_copy_and_build (TREE_OPERAND (name, 1),
7098 args, complain, in_decl,
7099 /*function_p=*/false);
7100 name = TREE_OPERAND (name, 0);
7104 is_template = false;
7105 template_args = NULL_TREE;
7108 /* Substitute into the qualifying scope. When there are no ARGS, we
7109 are just trying to simplify a non-dependent expression. In that
7110 case the qualifying scope may be dependent, and, in any case,
7111 substituting will not help. */
7112 scope = TREE_OPERAND (qualified_id, 0);
7115 scope = tsubst (scope, args, complain, in_decl);
7116 expr = tsubst_copy (name, args, complain, in_decl);
7121 my_friendly_assert (!dependent_type_p (scope), 20030729);
7123 if (!BASELINK_P (name) && !DECL_P (expr))
7124 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7127 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7130 /* Remember that there was a reference to this entity. */
7134 if (!args && TREE_CODE (expr) == VAR_DECL)
7135 expr = DECL_INITIAL (expr);
7139 expr = lookup_template_function (expr, template_args);
7141 if (expr == error_mark_node && complain & tf_error)
7142 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1));
7143 else if (TYPE_P (scope))
7145 expr = (adjust_result_of_qualified_name_lookup
7146 (expr, scope, current_class_type));
7147 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7153 /* Like tsubst, but deals with expressions. This function just replaces
7154 template parms; to finish processing the resultant expression, use
7158 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7160 enum tree_code code;
7163 if (t == NULL_TREE || t == error_mark_node)
7166 code = TREE_CODE (t);
7171 r = retrieve_local_specialization (t);
7172 my_friendly_assert (r != NULL, 20020903);
7180 if (DECL_TEMPLATE_PARM_P (t))
7181 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7182 /* There is no need to substitute into namespace-scope
7184 if (DECL_NAMESPACE_SCOPE_P (t))
7187 /* Unfortunately, we cannot just call lookup_name here.
7190 template <int I> int f() {
7192 struct S { void g() { E e = a; } };
7195 When we instantiate f<7>::S::g(), say, lookup_name is not
7196 clever enough to find f<7>::a. */
7198 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7199 /*entering_scope=*/0);
7201 for (v = TYPE_VALUES (enum_type);
7204 if (TREE_PURPOSE (v) == DECL_NAME (t))
7205 return TREE_VALUE (v);
7207 /* We didn't find the name. That should never happen; if
7208 name-lookup found it during preliminary parsing, we
7209 should find it again here during instantiation. */
7215 if (DECL_CONTEXT (t))
7219 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7220 /*entering_scope=*/1);
7221 if (ctx != DECL_CONTEXT (t))
7222 return lookup_field (ctx, DECL_NAME (t), 0, false);
7228 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7229 || local_variable_p (t))
7230 t = tsubst (t, args, complain, in_decl);
7235 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7238 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7239 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7240 args, complain, in_decl);
7241 else if (is_member_template (t))
7242 return tsubst (t, args, complain, in_decl);
7243 else if (DECL_CLASS_SCOPE_P (t)
7244 && uses_template_parms (DECL_CONTEXT (t)))
7246 /* Template template argument like the following example need
7249 template <template <class> class TT> struct C {};
7250 template <class T> struct D {
7251 template <class U> struct E {};
7256 We are processing the template argument `E' in #1 for
7257 the template instantiation #2. Originally, `E' is a
7258 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7259 have to substitute this with one having context `D<int>'. */
7261 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7262 return lookup_field (context, DECL_NAME(t), 0, false);
7265 /* Ordinary template template argument. */
7269 case REINTERPRET_CAST_EXPR:
7270 case CONST_CAST_EXPR:
7271 case STATIC_CAST_EXPR:
7272 case DYNAMIC_CAST_EXPR:
7275 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7276 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7280 case TRUTH_NOT_EXPR:
7283 case CONVERT_EXPR: /* Unary + */
7292 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7293 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7300 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7301 name = TREE_OPERAND (t, 1);
7302 if (TREE_CODE (name) == BIT_NOT_EXPR)
7304 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7306 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7308 else if (TREE_CODE (name) == SCOPE_REF
7309 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7311 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7313 name = TREE_OPERAND (name, 1);
7314 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7316 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7317 name = build_nt (SCOPE_REF, base, name);
7319 else if (TREE_CODE (name) == BASELINK)
7320 name = tsubst_baselink (name,
7321 non_reference (TREE_TYPE (object)),
7325 name = tsubst_copy (name, args, complain, in_decl);
7326 return build_nt (COMPONENT_REF, object, name);
7332 case TRUNC_DIV_EXPR:
7334 case FLOOR_DIV_EXPR:
7335 case ROUND_DIV_EXPR:
7336 case EXACT_DIV_EXPR:
7338 case BIT_ANDTC_EXPR:
7341 case TRUNC_MOD_EXPR:
7342 case FLOOR_MOD_EXPR:
7343 case TRUTH_ANDIF_EXPR:
7344 case TRUTH_ORIF_EXPR:
7345 case TRUTH_AND_EXPR:
7364 case PREDECREMENT_EXPR:
7365 case PREINCREMENT_EXPR:
7366 case POSTDECREMENT_EXPR:
7367 case POSTINCREMENT_EXPR:
7369 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7370 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7373 return build_nt (code,
7374 tsubst_copy (TREE_OPERAND (t, 0), args,
7376 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7381 /* This processing should really occur in tsubst_expr. However,
7382 tsubst_expr does not recurse into expressions, since it
7383 assumes that there aren't any statements inside them. So, we
7384 need to expand the STMT_EXPR here. */
7385 if (!processing_template_decl)
7387 tree stmt_expr = begin_stmt_expr ();
7389 tsubst_expr (STMT_EXPR_STMT (t), args,
7390 complain | tf_stmt_expr_cmpd, in_decl);
7391 return finish_stmt_expr (stmt_expr);
7398 case PSEUDO_DTOR_EXPR:
7401 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7402 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7403 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7410 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7411 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7412 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7413 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7420 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7421 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7422 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7423 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7427 case TEMPLATE_ID_EXPR:
7429 /* Substituted template arguments */
7430 tree fn = TREE_OPERAND (t, 0);
7431 tree targs = TREE_OPERAND (t, 1);
7433 fn = tsubst_copy (fn, args, complain, in_decl);
7434 targs = tsubst_template_args (targs, args, complain, in_decl);
7436 return lookup_template_function (fn, targs);
7441 tree purpose, value, chain;
7443 if (t == void_list_node)
7446 purpose = TREE_PURPOSE (t);
7448 purpose = tsubst_copy (purpose, args, complain, in_decl);
7449 value = TREE_VALUE (t);
7451 value = tsubst_copy (value, args, complain, in_decl);
7452 chain = TREE_CHAIN (t);
7453 if (chain && chain != void_type_node)
7454 chain = tsubst_copy (chain, args, complain, in_decl);
7455 if (purpose == TREE_PURPOSE (t)
7456 && value == TREE_VALUE (t)
7457 && chain == TREE_CHAIN (t))
7459 return tree_cons (purpose, value, chain);
7466 case TEMPLATE_TYPE_PARM:
7467 case TEMPLATE_TEMPLATE_PARM:
7468 case BOUND_TEMPLATE_TEMPLATE_PARM:
7469 case TEMPLATE_PARM_INDEX:
7471 case REFERENCE_TYPE:
7477 case UNBOUND_CLASS_TEMPLATE:
7480 return tsubst (t, args, complain, in_decl);
7482 case IDENTIFIER_NODE:
7483 if (IDENTIFIER_TYPENAME_P (t))
7485 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7486 return mangle_conv_op_name_for_type (new_type);
7493 r = build_constructor
7494 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7495 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7496 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7501 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7503 tsubst (TREE_TYPE (t), args, complain, in_decl));
7510 /* Like tsubst_copy for expressions, etc. but also does semantic
7514 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7517 tsubst_flags_t stmt_expr
7518 = complain & (tf_stmt_expr_cmpd | tf_stmt_expr_body);
7520 complain ^= stmt_expr;
7521 if (t == NULL_TREE || t == error_mark_node)
7524 if (processing_template_decl)
7525 return tsubst_copy (t, args, complain, in_decl);
7527 if (!STATEMENT_CODE_P (TREE_CODE (t)))
7528 return tsubst_copy_and_build (t, args, complain, in_decl,
7529 /*function_p=*/false);
7531 switch (TREE_CODE (t))
7533 case CTOR_INITIALIZER:
7535 finish_mem_initializers (tsubst_initializer_list
7536 (TREE_OPERAND (t, 0), args));
7541 finish_return_stmt (tsubst_expr (RETURN_STMT_EXPR (t),
7542 args, complain, in_decl));
7551 r = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
7552 if (stmt_expr & tf_stmt_expr_body && !TREE_CHAIN (t))
7553 finish_stmt_expr_expr (r);
7555 finish_expr_stmt (r);
7561 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
7562 args, complain, in_decl));
7571 decl = DECL_STMT_DECL (t);
7572 if (TREE_CODE (decl) == LABEL_DECL)
7573 finish_label_decl (DECL_NAME (decl));
7574 else if (TREE_CODE (decl) == USING_DECL)
7576 tree scope = DECL_INITIAL (decl);
7577 tree name = DECL_NAME (decl);
7580 scope = tsubst_expr (scope, args, complain, in_decl);
7581 decl = lookup_qualified_name (scope, name,
7582 /*is_type_p=*/0, /*complain=*/false);
7583 if (decl == error_mark_node)
7584 qualified_name_lookup_error (scope, name);
7586 do_local_using_decl (decl);
7590 init = DECL_INITIAL (decl);
7591 decl = tsubst (decl, args, complain, in_decl);
7592 if (decl != error_mark_node)
7595 DECL_INITIAL (decl) = error_mark_node;
7596 /* By marking the declaration as instantiated, we avoid
7597 trying to instantiate it. Since instantiate_decl can't
7598 handle local variables, and since we've already done
7599 all that needs to be done, that's the right thing to
7601 if (TREE_CODE (decl) == VAR_DECL)
7602 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7603 if (TREE_CODE (decl) == VAR_DECL
7604 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
7605 /* Anonymous aggregates are a special case. */
7606 finish_anon_union (decl);
7609 maybe_push_decl (decl);
7610 if (TREE_CODE (decl) == VAR_DECL
7611 && DECL_PRETTY_FUNCTION_P (decl))
7613 /* For __PRETTY_FUNCTION__ we have to adjust the
7615 const char *const name
7616 = cxx_printable_name (current_function_decl, 2);
7617 init = cp_fname_init (name);
7618 TREE_TYPE (decl) = TREE_TYPE (init);
7621 init = tsubst_expr (init, args, complain, in_decl);
7622 cp_finish_decl (decl, init, NULL_TREE, 0);
7627 /* A DECL_STMT can also be used as an expression, in the condition
7628 clause of an if/for/while construct. If we aren't followed by
7629 another statement, return our decl. */
7630 if (TREE_CHAIN (t) == NULL_TREE)
7639 stmt = begin_for_stmt ();
7640 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
7641 finish_for_init_stmt (stmt);
7642 finish_for_cond (tsubst_expr (FOR_COND (t),
7643 args, complain, in_decl),
7645 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
7646 finish_for_expr (tmp, stmt);
7647 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
7648 finish_for_stmt (stmt);
7655 stmt = begin_while_stmt ();
7656 finish_while_stmt_cond (tsubst_expr (WHILE_COND (t),
7657 args, complain, in_decl),
7659 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
7660 finish_while_stmt (stmt);
7667 stmt = begin_do_stmt ();
7668 tsubst_expr (DO_BODY (t), args, complain, in_decl);
7669 finish_do_body (stmt);
7670 finish_do_stmt (tsubst_expr (DO_COND (t),
7671 args, complain, in_decl),
7679 stmt = begin_if_stmt ();
7680 finish_if_stmt_cond (tsubst_expr (IF_COND (t),
7681 args, complain, in_decl),
7684 if (tmp = THEN_CLAUSE (t), tmp)
7686 tsubst_expr (tmp, args, complain, in_decl);
7687 finish_then_clause (stmt);
7690 if (tmp = ELSE_CLAUSE (t), tmp)
7692 begin_else_clause ();
7693 tsubst_expr (tmp, args, complain, in_decl);
7694 finish_else_clause (stmt);
7704 if (COMPOUND_STMT_BODY_BLOCK (t))
7705 stmt = begin_function_body ();
7707 stmt = begin_compound_stmt (COMPOUND_STMT_NO_SCOPE (t));
7709 tsubst_expr (COMPOUND_BODY (t), args,
7710 complain | ((stmt_expr & tf_stmt_expr_cmpd) << 1),
7713 if (COMPOUND_STMT_BODY_BLOCK (t))
7714 finish_function_body (stmt);
7716 finish_compound_stmt (stmt);
7722 finish_break_stmt ();
7727 finish_continue_stmt ();
7735 stmt = begin_switch_stmt ();
7736 val = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
7737 finish_switch_cond (val, stmt);
7738 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
7739 finish_switch_stmt (stmt);
7745 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
7746 tsubst_expr (CASE_HIGH (t), args, complain,
7751 input_line = STMT_LINENO (t);
7752 finish_label_stmt (DECL_NAME (LABEL_STMT_LABEL (t)));
7756 input_filename = FILE_STMT_FILENAME (t);
7757 add_stmt (build_nt (FILE_STMT, FILE_STMT_FILENAME_NODE (t)));
7762 tmp = GOTO_DESTINATION (t);
7763 if (TREE_CODE (tmp) != LABEL_DECL)
7764 /* Computed goto's must be tsubst'd into. On the other hand,
7765 non-computed gotos must not be; the identifier in question
7766 will have no binding. */
7767 tmp = tsubst_expr (tmp, args, complain, in_decl);
7769 tmp = DECL_NAME (tmp);
7770 finish_goto_stmt (tmp);
7775 tmp = finish_asm_stmt
7777 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
7778 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
7779 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
7780 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
7781 ASM_INPUT_P (tmp) = ASM_INPUT_P (t);
7788 stmt = begin_try_block ();
7789 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7790 finish_cleanup_try_block (stmt);
7791 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
7797 if (FN_TRY_BLOCK_P (t))
7798 stmt = begin_function_try_block ();
7800 stmt = begin_try_block ();
7802 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7804 if (FN_TRY_BLOCK_P (t))
7805 finish_function_try_block (stmt);
7807 finish_try_block (stmt);
7809 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
7810 if (FN_TRY_BLOCK_P (t))
7811 finish_function_handler_sequence (stmt);
7813 finish_handler_sequence (stmt);
7822 stmt = begin_handler ();
7823 if (HANDLER_PARMS (t))
7825 decl = DECL_STMT_DECL (HANDLER_PARMS (t));
7826 decl = tsubst (decl, args, complain, in_decl);
7827 /* Prevent instantiate_decl from trying to instantiate
7828 this variable. We've already done all that needs to be
7830 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7834 finish_handler_parms (decl, stmt);
7835 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
7836 finish_handler (stmt);
7842 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
7849 return tsubst_expr (TREE_CHAIN (t), args, complain | stmt_expr, in_decl);
7852 /* T is a postfix-expression that is not being used in a function
7853 call. Return the substituted version of T. */
7856 tsubst_non_call_postfix_expression (tree t, tree args,
7857 tsubst_flags_t complain,
7860 if (TREE_CODE (t) == SCOPE_REF)
7861 t = tsubst_qualified_id (t, args, complain, in_decl,
7862 /*done=*/false, /*address_p=*/false);
7864 t = tsubst_copy_and_build (t, args, complain, in_decl,
7865 /*function_p=*/false);
7870 /* Like tsubst but deals with expressions and performs semantic
7871 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
7874 tsubst_copy_and_build (tree t,
7876 tsubst_flags_t complain,
7880 #define RECUR(NODE) \
7881 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
7885 if (t == NULL_TREE || t == error_mark_node)
7888 switch (TREE_CODE (t))
7893 case IDENTIFIER_NODE:
7897 tree qualifying_class;
7898 bool non_constant_expression_p;
7899 const char *error_msg;
7901 if (IDENTIFIER_TYPENAME_P (t))
7903 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7904 t = mangle_conv_op_name_for_type (new_type);
7907 /* Look up the name. */
7908 decl = lookup_name (t, 0);
7910 /* By convention, expressions use ERROR_MARK_NODE to indicate
7911 failure, not NULL_TREE. */
7912 if (decl == NULL_TREE)
7913 decl = error_mark_node;
7915 decl = finish_id_expression (t, decl, NULL_TREE,
7918 /*constant_expression_p=*/false,
7919 /*allow_non_constant_expression_p=*/false,
7920 &non_constant_expression_p,
7924 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
7925 decl = unqualified_name_lookup_error (decl);
7929 case TEMPLATE_ID_EXPR:
7932 tree template = RECUR (TREE_OPERAND (t, 0));
7933 tree targs = RECUR (TREE_OPERAND (t, 1));
7935 if (TREE_CODE (template) == COMPONENT_REF)
7937 object = TREE_OPERAND (template, 0);
7938 template = TREE_OPERAND (template, 1);
7942 template = lookup_template_function (template, targs);
7945 return build (COMPONENT_REF, TREE_TYPE (template),
7952 return build_x_indirect_ref (RECUR (TREE_OPERAND (t, 0)), "unary *");
7955 return build_functional_cast
7956 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7957 RECUR (TREE_OPERAND (t, 0)));
7959 case REINTERPRET_CAST_EXPR:
7960 return build_reinterpret_cast
7961 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7962 RECUR (TREE_OPERAND (t, 0)));
7964 case CONST_CAST_EXPR:
7965 return build_const_cast
7966 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7967 RECUR (TREE_OPERAND (t, 0)));
7969 case DYNAMIC_CAST_EXPR:
7970 return build_dynamic_cast
7971 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7972 RECUR (TREE_OPERAND (t, 0)));
7974 case STATIC_CAST_EXPR:
7975 return build_static_cast
7976 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7977 RECUR (TREE_OPERAND (t, 0)));
7979 case POSTDECREMENT_EXPR:
7980 case POSTINCREMENT_EXPR:
7981 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
7982 args, complain, in_decl);
7983 return build_x_unary_op (TREE_CODE (t), op1);
7985 case PREDECREMENT_EXPR:
7986 case PREINCREMENT_EXPR:
7990 case TRUTH_NOT_EXPR:
7991 case CONVERT_EXPR: /* Unary + */
7994 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
7997 op1 = TREE_OPERAND (t, 0);
7998 if (TREE_CODE (op1) == SCOPE_REF)
7999 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8000 /*done=*/true, /*address_p=*/true);
8002 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8004 return build_x_unary_op (ADDR_EXPR, op1);
8009 case TRUNC_DIV_EXPR:
8011 case FLOOR_DIV_EXPR:
8012 case ROUND_DIV_EXPR:
8013 case EXACT_DIV_EXPR:
8015 case BIT_ANDTC_EXPR:
8018 case TRUNC_MOD_EXPR:
8019 case FLOOR_MOD_EXPR:
8020 case TRUTH_ANDIF_EXPR:
8021 case TRUTH_ORIF_EXPR:
8022 case TRUTH_AND_EXPR:
8038 return build_x_binary_op
8040 RECUR (TREE_OPERAND (t, 0)),
8041 RECUR (TREE_OPERAND (t, 1)));
8044 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8045 /*address_p=*/false);
8048 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8051 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)));
8053 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8054 args, complain, in_decl);
8055 /* Remember that there was a reference to this entity. */
8058 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8062 op1 = TREE_OPERAND (t, 0);
8065 /* When there are no ARGS, we are trying to evaluate a
8066 non-dependent expression from the parser. Trying to do
8067 the substitutions may not work. */
8069 op1 = TREE_TYPE (op1);
8077 if (TREE_CODE (t) == SIZEOF_EXPR)
8078 return finish_sizeof (op1);
8080 return finish_alignof (op1);
8083 return build_x_modify_expr
8084 (RECUR (TREE_OPERAND (t, 0)),
8085 TREE_CODE (TREE_OPERAND (t, 1)),
8086 RECUR (TREE_OPERAND (t, 2)));
8089 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8090 args, complain, in_decl);
8091 /* Remember that there was a reference to this entity. */
8094 return build_x_arrow (op1);
8098 (RECUR (TREE_OPERAND (t, 0)),
8099 RECUR (TREE_OPERAND (t, 1)),
8100 RECUR (TREE_OPERAND (t, 2)),
8101 NEW_EXPR_USE_GLOBAL (t));
8104 return delete_sanity
8105 (RECUR (TREE_OPERAND (t, 0)),
8106 RECUR (TREE_OPERAND (t, 1)),
8107 DELETE_EXPR_USE_VEC (t),
8108 DELETE_EXPR_USE_GLOBAL (t));
8111 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8112 RECUR (TREE_OPERAND (t, 1)));
8121 function = TREE_OPERAND (t, 0);
8122 /* To determine whether or not we should perform Koenig lookup
8123 we must look at the form of the FUNCTION. */
8124 koenig_p = !(/* Koenig lookup does not apply to qualified
8126 TREE_CODE (function) == SCOPE_REF
8127 /* Or to references to members of classes. */
8128 || TREE_CODE (function) == COMPONENT_REF
8129 /* If it is a FUNCTION_DECL or a baselink, then
8130 the name was already resolved when the
8131 template was parsed. */
8132 || TREE_CODE (function) == FUNCTION_DECL
8133 || TREE_CODE (function) == BASELINK);
8134 if (TREE_CODE (function) == SCOPE_REF)
8137 function = tsubst_qualified_id (function, args, complain, in_decl,
8139 /*address_p=*/false);
8143 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8144 && (TREE_CODE (TREE_OPERAND (function, 1))
8146 function = tsubst_copy_and_build (function, args, complain,
8151 call_args = RECUR (TREE_OPERAND (t, 1));
8153 if (BASELINK_P (function))
8157 && TREE_CODE (function) != TEMPLATE_ID_EXPR
8158 && (is_overloaded_fn (function)
8159 || DECL_P (function)
8160 || TREE_CODE (function) == IDENTIFIER_NODE))
8163 function = perform_koenig_lookup (function, call_args);
8164 else if (TREE_CODE (function) == IDENTIFIER_NODE)
8165 function = unqualified_name_lookup_error (function);
8168 /* Remember that there was a reference to this entity. */
8169 if (DECL_P (function))
8170 mark_used (function);
8172 function = convert_from_reference (function);
8174 if (TREE_CODE (function) == OFFSET_REF)
8175 return build_offset_ref_call_from_tree (function, call_args);
8176 if (TREE_CODE (function) == COMPONENT_REF)
8177 return (build_new_method_call
8178 (TREE_OPERAND (function, 0),
8179 TREE_OPERAND (function, 1),
8180 call_args, NULL_TREE,
8181 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8182 return finish_call_expr (function, call_args,
8183 /*disallow_virtual=*/qualified_p);
8187 return build_x_conditional_expr
8188 (RECUR (TREE_OPERAND (t, 0)),
8189 RECUR (TREE_OPERAND (t, 1)),
8190 RECUR (TREE_OPERAND (t, 2)));
8192 case PSEUDO_DTOR_EXPR:
8193 return finish_pseudo_destructor_expr
8194 (RECUR (TREE_OPERAND (t, 0)),
8195 RECUR (TREE_OPERAND (t, 1)),
8196 RECUR (TREE_OPERAND (t, 2)));
8200 tree purpose, value, chain;
8202 if (t == void_list_node)
8205 purpose = TREE_PURPOSE (t);
8207 purpose = RECUR (purpose);
8208 value = TREE_VALUE (t);
8210 value = RECUR (value);
8211 chain = TREE_CHAIN (t);
8212 if (chain && chain != void_type_node)
8213 chain = RECUR (chain);
8214 if (purpose == TREE_PURPOSE (t)
8215 && value == TREE_VALUE (t)
8216 && chain == TREE_CHAIN (t))
8218 return tree_cons (purpose, value, chain);
8226 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8227 args, complain, in_decl);
8228 /* Remember that there was a reference to this entity. */
8229 if (DECL_P (object))
8232 member = TREE_OPERAND (t, 1);
8233 if (BASELINK_P (member))
8234 member = tsubst_baselink (member,
8235 non_reference (TREE_TYPE (object)),
8236 args, complain, in_decl);
8238 member = tsubst_copy (member, args, complain, in_decl);
8240 if (!CLASS_TYPE_P (TREE_TYPE (object)))
8242 if (TREE_CODE (member) == BIT_NOT_EXPR)
8243 return finish_pseudo_destructor_expr (object,
8245 TREE_TYPE (object));
8246 else if (TREE_CODE (member) == SCOPE_REF
8247 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8248 return finish_pseudo_destructor_expr (object,
8250 TREE_TYPE (object));
8252 else if (TREE_CODE (member) == SCOPE_REF
8253 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8258 /* Lookup the template functions now that we know what the
8260 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8261 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8262 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8263 /*is_type=*/0, /*complain=*/false);
8264 if (BASELINK_P (member))
8265 BASELINK_FUNCTIONS (member)
8266 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8270 qualified_name_lookup_error (TREE_TYPE (object), tmpl);
8271 return error_mark_node;
8274 else if (TREE_CODE (member) == FIELD_DECL)
8275 return finish_non_static_data_member (member, object, NULL_TREE);
8277 return finish_class_member_access_expr (object, member);
8282 (RECUR (TREE_OPERAND (t, 0)));
8288 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8291 /* digest_init will do the wrong thing if we let it. */
8292 if (type && TYPE_PTRMEMFUNC_P (type))
8296 /* We do not want to process the purpose of aggregate
8297 initializers as they are identifier nodes which will be
8298 looked up by digest_init. */
8299 purpose_p = !(type && IS_AGGR_TYPE (type));
8300 for (elts = CONSTRUCTOR_ELTS (t);
8302 elts = TREE_CHAIN (elts))
8304 tree purpose = TREE_PURPOSE (elts);
8305 tree value = TREE_VALUE (elts);
8307 if (purpose && purpose_p)
8308 purpose = RECUR (purpose);
8309 value = RECUR (value);
8310 r = tree_cons (purpose, value, r);
8313 r = build_constructor (NULL_TREE, nreverse (r));
8314 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8317 return digest_init (type, r, 0);
8323 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8324 if (TYPE_P (operand_0))
8325 return get_typeid (operand_0);
8326 return build_typeid (operand_0);
8330 return convert_from_reference (tsubst_copy (t, args, complain, in_decl));
8334 t = tsubst_copy (t, args, complain, in_decl);
8336 /* If there are no ARGS, then we are evaluating a
8337 non-dependent expression. If the expression is
8338 non-dependent, the variable must be a constant. */
8339 t = DECL_INITIAL (t);
8340 return convert_from_reference (t);
8343 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8344 tsubst_copy (TREE_TYPE (t), args, complain,
8348 return tsubst_copy (t, args, complain, in_decl);
8354 /* Verify that the instantiated ARGS are valid. For type arguments,
8355 make sure that the type's linkage is ok. For non-type arguments,
8356 make sure they are constants if they are integral or enumerations.
8357 Emit an error under control of COMPLAIN, and return TRUE on error. */
8360 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8362 int ix, len = DECL_NTPARMS (tmpl);
8363 bool result = false;
8365 for (ix = 0; ix != len; ix++)
8367 tree t = TREE_VEC_ELT (args, ix);
8371 /* [basic.link]: A name with no linkage (notably, the name
8372 of a class or enumeration declared in a local scope)
8373 shall not be used to declare an entity with linkage.
8374 This implies that names with no linkage cannot be used as
8375 template arguments. */
8376 tree nt = no_linkage_check (t);
8380 if (!(complain & tf_error))
8382 else if (TYPE_ANONYMOUS_P (nt))
8383 error ("`%T' uses anonymous type", t);
8385 error ("`%T' uses local type `%T'", t, nt);
8388 /* In order to avoid all sorts of complications, we do not
8389 allow variably-modified types as template arguments. */
8390 else if (variably_modified_type_p (t))
8392 if (complain & tf_error)
8393 error ("`%T' is a variably modified type", t);
8397 /* A non-type argument of integral or enumerated type must be a
8399 else if (TREE_TYPE (t)
8400 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8401 && !TREE_CONSTANT (t))
8403 if (complain & tf_error)
8404 error ("integral expression `%E' is not constant", t);
8408 if (result && complain & tf_error)
8409 error (" trying to instantiate `%D'", tmpl);
8413 /* Instantiate the indicated variable or function template TMPL with
8414 the template arguments in TARG_PTR. */
8417 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8423 if (tmpl == error_mark_node)
8424 return error_mark_node;
8426 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 283);
8428 /* If this function is a clone, handle it specially. */
8429 if (DECL_CLONED_FUNCTION_P (tmpl))
8431 tree spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8435 /* Look for the clone. */
8436 for (clone = TREE_CHAIN (spec);
8437 clone && DECL_CLONED_FUNCTION_P (clone);
8438 clone = TREE_CHAIN (clone))
8439 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8441 /* We should always have found the clone by now. */
8446 /* Check to see if we already have this specialization. */
8447 spec = retrieve_specialization (tmpl, targ_ptr);
8448 if (spec != NULL_TREE)
8451 gen_tmpl = most_general_template (tmpl);
8452 if (tmpl != gen_tmpl)
8454 /* The TMPL is a partial instantiation. To get a full set of
8455 arguments we must add the arguments used to perform the
8456 partial instantiation. */
8457 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
8460 /* Check to see if we already have this specialization. */
8461 spec = retrieve_specialization (gen_tmpl, targ_ptr);
8462 if (spec != NULL_TREE)
8466 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
8468 return error_mark_node;
8470 /* We are building a FUNCTION_DECL, during which the access of its
8471 parameters and return types have to be checked. However this
8472 FUNCTION_DECL which is the desired context for access checking
8473 is not built yet. We solve this chicken-and-egg problem by
8474 deferring all checks until we have the FUNCTION_DECL. */
8475 push_deferring_access_checks (dk_deferred);
8477 /* substitute template parameters */
8478 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
8479 targ_ptr, complain, gen_tmpl);
8481 /* Now we know the specialization, compute access previously
8483 push_access_scope (fndecl);
8484 perform_deferred_access_checks ();
8485 pop_access_scope (fndecl);
8486 pop_deferring_access_checks ();
8488 /* The DECL_TI_TEMPLATE should always be the immediate parent
8489 template, not the most general template. */
8490 DECL_TI_TEMPLATE (fndecl) = tmpl;
8492 if (flag_external_templates)
8493 add_pending_template (fndecl);
8495 /* If we've just instantiated the main entry point for a function,
8496 instantiate all the alternate entry points as well. We do this
8497 by cloning the instantiation of the main entry point, not by
8498 instantiating the template clones. */
8499 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
8500 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
8505 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8506 arguments that are being used when calling it. TARGS is a vector
8507 into which the deduced template arguments are placed.
8509 Return zero for success, 2 for an incomplete match that doesn't resolve
8510 all the types, and 1 for complete failure. An error message will be
8511 printed only for an incomplete match.
8513 If FN is a conversion operator, or we are trying to produce a specific
8514 specialization, RETURN_TYPE is the return type desired.
8516 The EXPLICIT_TARGS are explicit template arguments provided via a
8519 The parameter STRICT is one of:
8522 We are deducing arguments for a function call, as in
8526 We are deducing arguments for a conversion function, as in
8530 We are deducing arguments when doing an explicit instantiation
8531 as in [temp.explicit], when determining an explicit specialization
8532 as in [temp.expl.spec], or when taking the address of a function
8533 template, as in [temp.deduct.funcaddr].
8536 We are deducing arguments when calculating the partial
8537 ordering between specializations of function or class
8538 templates, as in [temp.func.order] and [temp.class.order].
8540 LEN is the number of parms to consider before returning success, or -1
8541 for all. This is used in partial ordering to avoid comparing parms for
8542 which no actual argument was passed, since they are not considered in
8543 overload resolution (and are explicitly excluded from consideration in
8544 partial ordering in [temp.func.order]/6). */
8547 fn_type_unification (tree fn,
8548 tree explicit_targs,
8552 unification_kind_t strict,
8559 my_friendly_assert (TREE_CODE (fn) == TEMPLATE_DECL, 0);
8561 fntype = TREE_TYPE (fn);
8566 The specified template arguments must match the template
8567 parameters in kind (i.e., type, nontype, template), and there
8568 must not be more arguments than there are parameters;
8569 otherwise type deduction fails.
8571 Nontype arguments must match the types of the corresponding
8572 nontype template parameters, or must be convertible to the
8573 types of the corresponding nontype parameters as specified in
8574 _temp.arg.nontype_, otherwise type deduction fails.
8576 All references in the function type of the function template
8577 to the corresponding template parameters are replaced by the
8578 specified template argument values. If a substitution in a
8579 template parameter or in the function type of the function
8580 template results in an invalid type, type deduction fails. */
8582 tree converted_args;
8586 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8587 explicit_targs, NULL_TREE, tf_none,
8588 /*require_all_arguments=*/0));
8589 if (converted_args == error_mark_node)
8592 /* Substitute the explicit args into the function type. This is
8593 necessary so that, for instance, explicitly declared function
8594 arguments can match null pointed constants. If we were given
8595 an incomplete set of explicit args, we must not do semantic
8596 processing during substitution as we could create partial
8598 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
8599 processing_template_decl += incomplete;
8600 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
8601 processing_template_decl -= incomplete;
8603 if (fntype == error_mark_node)
8606 /* Place the explicitly specified arguments in TARGS. */
8607 for (i = NUM_TMPL_ARGS (converted_args); i--;)
8608 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
8611 parms = TYPE_ARG_TYPES (fntype);
8612 /* Never do unification on the 'this' parameter. */
8613 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
8614 parms = TREE_CHAIN (parms);
8618 /* We've been given a return type to match, prepend it. */
8619 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
8620 args = tree_cons (NULL_TREE, return_type, args);
8625 /* We allow incomplete unification without an error message here
8626 because the standard doesn't seem to explicitly prohibit it. Our
8627 callers must be ready to deal with unification failures in any
8629 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8630 targs, parms, args, /*subr=*/0,
8631 strict, /*allow_incomplete*/1, len);
8634 /* All is well so far. Now, check:
8638 When all template arguments have been deduced, all uses of
8639 template parameters in nondeduced contexts are replaced with
8640 the corresponding deduced argument values. If the
8641 substitution results in an invalid type, as described above,
8642 type deduction fails. */
8643 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
8650 /* Adjust types before performing type deduction, as described in
8651 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
8652 sections are symmetric. PARM is the type of a function parameter
8653 or the return type of the conversion function. ARG is the type of
8654 the argument passed to the call, or the type of the value
8655 initialized with the result of the conversion function. */
8658 maybe_adjust_types_for_deduction (unification_kind_t strict,
8671 /* Swap PARM and ARG throughout the remainder of this
8672 function; the handling is precisely symmetric since PARM
8673 will initialize ARG rather than vice versa. */
8681 /* There is nothing to do in this case. */
8685 /* DR 214. [temp.func.order] is underspecified, and leads to no
8686 ordering between things like `T *' and `T const &' for `U *'.
8687 The former has T=U and the latter T=U*. The former looks more
8688 specialized and John Spicer considers it well-formed (the EDG
8689 compiler accepts it).
8691 John also confirms that deduction should proceed as in a function
8692 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
8693 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
8694 to an actual call can have such a type.
8696 If both ARG and PARM are REFERENCE_TYPE, we change neither.
8697 If only ARG is a REFERENCE_TYPE, we look through that and then
8698 proceed as with DEDUCE_CALL (which could further convert it). */
8699 if (TREE_CODE (*arg) == REFERENCE_TYPE)
8701 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8703 *arg = TREE_TYPE (*arg);
8710 if (TREE_CODE (*parm) != REFERENCE_TYPE)
8712 /* [temp.deduct.call]
8714 If P is not a reference type:
8716 --If A is an array type, the pointer type produced by the
8717 array-to-pointer standard conversion (_conv.array_) is
8718 used in place of A for type deduction; otherwise,
8720 --If A is a function type, the pointer type produced by
8721 the function-to-pointer standard conversion
8722 (_conv.func_) is used in place of A for type deduction;
8725 --If A is a cv-qualified type, the top level
8726 cv-qualifiers of A's type are ignored for type
8728 if (TREE_CODE (*arg) == ARRAY_TYPE)
8729 *arg = build_pointer_type (TREE_TYPE (*arg));
8730 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
8731 *arg = build_pointer_type (*arg);
8733 *arg = TYPE_MAIN_VARIANT (*arg);
8736 /* [temp.deduct.call]
8738 If P is a cv-qualified type, the top level cv-qualifiers
8739 of P's type are ignored for type deduction. If P is a
8740 reference type, the type referred to by P is used for
8742 *parm = TYPE_MAIN_VARIANT (*parm);
8743 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8745 *parm = TREE_TYPE (*parm);
8746 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
8749 /* DR 322. For conversion deduction, remove a reference type on parm
8750 too (which has been swapped into ARG). */
8751 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
8752 *arg = TREE_TYPE (*arg);
8757 /* Most parms like fn_type_unification.
8759 If SUBR is 1, we're being called recursively (to unify the
8760 arguments of a function or method parameter of a function
8764 type_unification_real (tree tparms,
8769 unification_kind_t strict,
8770 int allow_incomplete,
8775 int ntparms = TREE_VEC_LENGTH (tparms);
8777 int saw_undeduced = 0;
8781 my_friendly_assert (TREE_CODE (tparms) == TREE_VEC, 289);
8782 my_friendly_assert (xparms == NULL_TREE
8783 || TREE_CODE (xparms) == TREE_LIST, 290);
8784 my_friendly_assert (!xargs || TREE_CODE (xargs) == TREE_LIST, 291);
8785 my_friendly_assert (ntparms > 0, 292);
8790 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
8791 | UNIFY_ALLOW_DERIVED);
8795 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
8799 sub_strict = UNIFY_ALLOW_NONE;
8803 sub_strict = UNIFY_ALLOW_NONE;
8819 && parms != void_list_node
8821 && args != void_list_node)
8823 parm = TREE_VALUE (parms);
8824 parms = TREE_CHAIN (parms);
8825 arg = TREE_VALUE (args);
8826 args = TREE_CHAIN (args);
8828 if (arg == error_mark_node)
8830 if (arg == unknown_type_node)
8831 /* We can't deduce anything from this, but we might get all the
8832 template args from other function args. */
8835 /* Conversions will be performed on a function argument that
8836 corresponds with a function parameter that contains only
8837 non-deducible template parameters and explicitly specified
8838 template parameters. */
8839 if (! uses_template_parms (parm))
8844 type = TREE_TYPE (arg);
8851 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
8853 if (same_type_p (parm, type))
8857 /* It might work; we shouldn't check now, because we might
8858 get into infinite recursion. Overload resolution will
8867 my_friendly_assert (TREE_TYPE (arg) != NULL_TREE, 293);
8868 if (type_unknown_p (arg))
8870 /* [temp.deduct.type] A template-argument can be deduced from
8871 a pointer to function or pointer to member function
8872 argument if the set of overloaded functions does not
8873 contain function templates and at most one of a set of
8874 overloaded functions provides a unique match. */
8876 if (resolve_overloaded_unification
8877 (tparms, targs, parm, arg, strict, sub_strict)
8882 arg = TREE_TYPE (arg);
8883 if (arg == error_mark_node)
8888 int arg_strict = sub_strict;
8891 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
8893 if (unify (tparms, targs, parm, arg, arg_strict))
8897 /* Are we done with the interesting parms? */
8901 /* Fail if we've reached the end of the parm list, and more args
8902 are present, and the parm list isn't variadic. */
8903 if (args && args != void_list_node && parms == void_list_node)
8905 /* Fail if parms are left and they don't have default values. */
8907 && parms != void_list_node
8908 && TREE_PURPOSE (parms) == NULL_TREE)
8913 for (i = 0; i < ntparms; i++)
8914 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
8916 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
8918 /* If this is an undeduced nontype parameter that depends on
8919 a type parameter, try another pass; its type may have been
8920 deduced from a later argument than the one from which
8921 this parameter can be deduced. */
8922 if (TREE_CODE (tparm) == PARM_DECL
8923 && uses_template_parms (TREE_TYPE (tparm))
8924 && !saw_undeduced++)
8927 if (!allow_incomplete)
8928 error ("incomplete type unification");
8934 /* Subroutine of type_unification_real. Args are like the variables at the
8935 call site. ARG is an overloaded function (or template-id); we try
8936 deducing template args from each of the overloads, and if only one
8937 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
8940 resolve_overloaded_unification (tree tparms,
8944 unification_kind_t strict,
8947 tree tempargs = copy_node (targs);
8950 if (TREE_CODE (arg) == ADDR_EXPR)
8951 arg = TREE_OPERAND (arg, 0);
8953 if (TREE_CODE (arg) == COMPONENT_REF)
8954 /* Handle `&x' where `x' is some static or non-static member
8956 arg = TREE_OPERAND (arg, 1);
8958 if (TREE_CODE (arg) == OFFSET_REF)
8959 arg = TREE_OPERAND (arg, 1);
8961 /* Strip baselink information. */
8962 if (BASELINK_P (arg))
8963 arg = BASELINK_FUNCTIONS (arg);
8965 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
8967 /* If we got some explicit template args, we need to plug them into
8968 the affected templates before we try to unify, in case the
8969 explicit args will completely resolve the templates in question. */
8971 tree expl_subargs = TREE_OPERAND (arg, 1);
8972 arg = TREE_OPERAND (arg, 0);
8974 for (; arg; arg = OVL_NEXT (arg))
8976 tree fn = OVL_CURRENT (arg);
8979 if (TREE_CODE (fn) != TEMPLATE_DECL)
8982 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
8986 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
8987 if (TREE_CODE (elem) == METHOD_TYPE)
8988 elem = build_ptrmemfunc_type (build_pointer_type (elem));
8989 good += try_one_overload (tparms, targs, tempargs, parm, elem,
8990 strict, sub_strict);
8994 else if (TREE_CODE (arg) == OVERLOAD
8995 || TREE_CODE (arg) == FUNCTION_DECL)
8997 for (; arg; arg = OVL_NEXT (arg))
8999 tree type = TREE_TYPE (OVL_CURRENT (arg));
9000 if (TREE_CODE (type) == METHOD_TYPE)
9001 type = build_ptrmemfunc_type (build_pointer_type (type));
9002 good += try_one_overload (tparms, targs, tempargs, parm,
9004 strict, sub_strict);
9010 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9011 to function or pointer to member function argument if the set of
9012 overloaded functions does not contain function templates and at most
9013 one of a set of overloaded functions provides a unique match.
9015 So if we found multiple possibilities, we return success but don't
9020 int i = TREE_VEC_LENGTH (targs);
9022 if (TREE_VEC_ELT (tempargs, i))
9023 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9031 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9032 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9033 different overloads deduce different arguments for a given parm.
9034 Returns 1 on success. */
9037 try_one_overload (tree tparms,
9042 unification_kind_t strict,
9049 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9050 to function or pointer to member function argument if the set of
9051 overloaded functions does not contain function templates and at most
9052 one of a set of overloaded functions provides a unique match.
9054 So if this is a template, just return success. */
9056 if (uses_template_parms (arg))
9059 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9061 /* We don't copy orig_targs for this because if we have already deduced
9062 some template args from previous args, unify would complain when we
9063 try to deduce a template parameter for the same argument, even though
9064 there isn't really a conflict. */
9065 nargs = TREE_VEC_LENGTH (targs);
9066 tempargs = make_tree_vec (nargs);
9068 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9071 /* First make sure we didn't deduce anything that conflicts with
9072 explicitly specified args. */
9073 for (i = nargs; i--; )
9075 tree elt = TREE_VEC_ELT (tempargs, i);
9076 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9078 if (elt == NULL_TREE)
9080 else if (uses_template_parms (elt))
9082 /* Since we're unifying against ourselves, we will fill in template
9083 args used in the function parm list with our own template parms.
9085 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9088 else if (oldelt && ! template_args_equal (oldelt, elt))
9092 for (i = nargs; i--; )
9094 tree elt = TREE_VEC_ELT (tempargs, i);
9097 TREE_VEC_ELT (targs, i) = elt;
9103 /* Verify that nondeduce template argument agrees with the type
9104 obtained from argument deduction. Return nonzero if the
9109 struct A { typedef int X; };
9110 template <class T, class U> struct C {};
9111 template <class T> struct C<T, typename T::X> {};
9113 Then with the instantiation `C<A, int>', we can deduce that
9114 `T' is `A' but unify () does not check whether `typename T::X'
9115 is `int'. This function ensure that they agree.
9117 TARGS, PARMS are the same as the arguments of unify.
9118 ARGS contains template arguments from all levels. */
9121 verify_class_unification (tree targs, tree parms, tree args)
9123 parms = tsubst (parms, add_outermost_template_args (args, targs),
9124 tf_none, NULL_TREE);
9125 if (parms == error_mark_node)
9128 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9131 /* PARM is a template class (perhaps with unbound template
9132 parameters). ARG is a fully instantiated type. If ARG can be
9133 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9134 TARGS are as for unify. */
9137 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9141 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9142 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9143 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9146 /* We need to make a new template argument vector for the call to
9147 unify. If we used TARGS, we'd clutter it up with the result of
9148 the attempted unification, even if this class didn't work out.
9149 We also don't want to commit ourselves to all the unifications
9150 we've already done, since unification is supposed to be done on
9151 an argument-by-argument basis. In other words, consider the
9152 following pathological case:
9154 template <int I, int J, int K>
9157 template <int I, int J>
9158 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9160 template <int I, int J, int K>
9161 void f(S<I, J, K>, S<I, I, I>);
9170 Now, by the time we consider the unification involving `s2', we
9171 already know that we must have `f<0, 0, 0>'. But, even though
9172 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9173 because there are two ways to unify base classes of S<0, 1, 2>
9174 with S<I, I, I>. If we kept the already deduced knowledge, we
9175 would reject the possibility I=1. */
9176 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9178 /* If unification failed, we're done. */
9179 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9180 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9186 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
9187 have already discovered to be satisfactory. ARG_BINFO is the binfo
9188 for the base class of ARG that we are currently examining. */
9191 get_template_base_recursive (tree tparms,
9200 tree arg = BINFO_TYPE (arg_binfo);
9202 if (!(flags & GTB_IGNORE_TYPE))
9204 tree r = try_class_unification (tparms, targs,
9207 /* If there is more than one satisfactory baseclass, then:
9211 If they yield more than one possible deduced A, the type
9215 if (r && rval && !same_type_p (r, rval))
9216 return error_mark_node;
9221 binfos = BINFO_BASETYPES (arg_binfo);
9222 n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
9224 /* Process base types. */
9225 for (i = 0; i < n_baselinks; i++)
9227 tree base_binfo = TREE_VEC_ELT (binfos, i);
9230 /* Skip this base, if we've already seen it. */
9231 if (BINFO_MARKED (base_binfo))
9235 (flags & GTB_VIA_VIRTUAL) || TREE_VIA_VIRTUAL (base_binfo);
9237 /* When searching for a non-virtual, we cannot mark virtually
9240 BINFO_MARKED (base_binfo) = 1;
9242 rval = get_template_base_recursive (tparms, targs,
9246 GTB_VIA_VIRTUAL * this_virtual);
9248 /* If we discovered more than one matching base class, we can
9250 if (rval == error_mark_node)
9251 return error_mark_node;
9257 /* Given a template type PARM and a class type ARG, find the unique
9258 base type in ARG that is an instance of PARM. We do not examine
9259 ARG itself; only its base-classes. If there is no appropriate base
9260 class, return NULL_TREE. If there is more than one, return
9261 error_mark_node. PARM may be the type of a partial specialization,
9262 as well as a plain template type. Used by unify. */
9265 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9270 my_friendly_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)), 92);
9272 arg_binfo = TYPE_BINFO (complete_type (arg));
9273 rval = get_template_base_recursive (tparms, targs,
9278 /* Since get_template_base_recursive marks the bases classes, we
9279 must unmark them here. */
9280 dfs_walk (arg_binfo, dfs_unmark, markedp, 0);
9285 /* Returns the level of DECL, which declares a template parameter. */
9288 template_decl_level (tree decl)
9290 switch (TREE_CODE (decl))
9294 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9297 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9305 /* Decide whether ARG can be unified with PARM, considering only the
9306 cv-qualifiers of each type, given STRICT as documented for unify.
9307 Returns nonzero iff the unification is OK on that basis.*/
9310 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9312 int arg_quals = cp_type_quals (arg);
9313 int parm_quals = cp_type_quals (parm);
9315 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM)
9317 /* If the cvr quals of parm will not unify with ARG, they'll be
9318 ignored in instantiation, so we have to do the same here. */
9319 if (TREE_CODE (arg) == REFERENCE_TYPE)
9320 parm_quals &= ~(TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE);
9321 if (!POINTER_TYPE_P (arg) &&
9322 TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9323 parm_quals &= ~TYPE_QUAL_RESTRICT;
9326 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9327 && (arg_quals & parm_quals) != parm_quals)
9330 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9331 && (parm_quals & arg_quals) != arg_quals)
9337 /* Takes parameters as for type_unification. Returns 0 if the
9338 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9339 bitwise or of the following flags:
9342 Require an exact match between PARM and ARG.
9343 UNIFY_ALLOW_MORE_CV_QUAL:
9344 Allow the deduced ARG to be more cv-qualified (by qualification
9345 conversion) than ARG.
9346 UNIFY_ALLOW_LESS_CV_QUAL:
9347 Allow the deduced ARG to be less cv-qualified than ARG.
9348 UNIFY_ALLOW_DERIVED:
9349 Allow the deduced ARG to be a template base class of ARG,
9350 or a pointer to a template base class of the type pointed to by
9352 UNIFY_ALLOW_INTEGER:
9353 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9354 case for more information.
9355 UNIFY_ALLOW_OUTER_LEVEL:
9356 This is the outermost level of a deduction. Used to determine validity
9357 of qualification conversions. A valid qualification conversion must
9358 have const qualified pointers leading up to the inner type which
9359 requires additional CV quals, except at the outer level, where const
9360 is not required [conv.qual]. It would be normal to set this flag in
9361 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9362 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9363 This is the outermost level of a deduction, and PARM can be more CV
9364 qualified at this point.
9365 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9366 This is the outermost level of a deduction, and PARM can be less CV
9367 qualified at this point.
9368 UNIFY_ALLOW_MAX_CORRECTION:
9369 This is an INTEGER_TYPE's maximum value. Used if the range may
9370 have been derived from a size specification, such as an array size.
9371 If the size was given by a nontype template parameter N, the maximum
9372 value will have the form N-1. The flag says that we can (and indeed
9373 must) unify N with (ARG + 1), an exception to the normal rules on
9377 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9382 int strict_in = strict;
9384 /* I don't think this will do the right thing with respect to types.
9385 But the only case I've seen it in so far has been array bounds, where
9386 signedness is the only information lost, and I think that will be
9388 while (TREE_CODE (parm) == NOP_EXPR)
9389 parm = TREE_OPERAND (parm, 0);
9391 if (arg == error_mark_node)
9393 if (arg == unknown_type_node)
9394 /* We can't deduce anything from this, but we might get all the
9395 template args from other function args. */
9398 /* If PARM uses template parameters, then we can't bail out here,
9399 even if ARG == PARM, since we won't record unifications for the
9400 template parameters. We might need them if we're trying to
9401 figure out which of two things is more specialized. */
9402 if (arg == parm && !uses_template_parms (parm))
9405 /* Immediately reject some pairs that won't unify because of
9406 cv-qualification mismatches. */
9407 if (TREE_CODE (arg) == TREE_CODE (parm)
9409 /* It is the elements of the array which hold the cv quals of an array
9410 type, and the elements might be template type parms. We'll check
9412 && TREE_CODE (arg) != ARRAY_TYPE
9413 /* We check the cv-qualifiers when unifying with template type
9414 parameters below. We want to allow ARG `const T' to unify with
9415 PARM `T' for example, when computing which of two templates
9416 is more specialized, for example. */
9417 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9418 && !check_cv_quals_for_unify (strict_in, arg, parm))
9421 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9422 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9423 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9424 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9425 strict &= ~UNIFY_ALLOW_DERIVED;
9426 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9427 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9428 strict &= ~UNIFY_ALLOW_MAX_CORRECTION;
9430 switch (TREE_CODE (parm))
9434 case UNBOUND_CLASS_TEMPLATE:
9435 /* In a type which contains a nested-name-specifier, template
9436 argument values cannot be deduced for template parameters used
9437 within the nested-name-specifier. */
9440 case TEMPLATE_TYPE_PARM:
9441 case TEMPLATE_TEMPLATE_PARM:
9442 case BOUND_TEMPLATE_TEMPLATE_PARM:
9443 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9445 if (TEMPLATE_TYPE_LEVEL (parm)
9446 != template_decl_level (tparm))
9447 /* The PARM is not one we're trying to unify. Just check
9448 to see if it matches ARG. */
9449 return (TREE_CODE (arg) == TREE_CODE (parm)
9450 && same_type_p (parm, arg)) ? 0 : 1;
9451 idx = TEMPLATE_TYPE_IDX (parm);
9452 targ = TREE_VEC_ELT (targs, idx);
9453 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9455 /* Check for mixed types and values. */
9456 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9457 && TREE_CODE (tparm) != TYPE_DECL)
9458 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9459 && TREE_CODE (tparm) != TEMPLATE_DECL))
9462 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9464 /* ARG must be constructed from a template class or a template
9465 template parameter. */
9466 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9467 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9471 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9472 tree parmvec = TYPE_TI_ARGS (parm);
9473 tree argvec = TYPE_TI_ARGS (arg);
9475 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9478 /* The parameter and argument roles have to be switched here
9479 in order to handle default arguments properly. For example,
9480 template<template <class> class TT> void f(TT<int>)
9481 should be able to accept vector<int> which comes from
9482 template <class T, class Allocator = allocator>
9485 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9489 /* Deduce arguments T, i from TT<T> or TT<i>.
9490 We check each element of PARMVEC and ARGVEC individually
9491 rather than the whole TREE_VEC since they can have
9492 different number of elements. */
9494 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9496 tree t = TREE_VEC_ELT (parmvec, i);
9498 if (unify (tparms, targs, t,
9499 TREE_VEC_ELT (argvec, i),
9504 arg = TYPE_TI_TEMPLATE (arg);
9506 /* Fall through to deduce template name. */
9509 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9510 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9512 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9514 /* Simple cases: Value already set, does match or doesn't. */
9515 if (targ != NULL_TREE && template_args_equal (targ, arg))
9522 /* If PARM is `const T' and ARG is only `int', we don't have
9523 a match unless we are allowing additional qualification.
9524 If ARG is `const int' and PARM is just `T' that's OK;
9525 that binds `const int' to `T'. */
9526 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
9530 /* Consider the case where ARG is `const volatile int' and
9531 PARM is `const T'. Then, T should be `volatile int'. */
9532 arg = cp_build_qualified_type_real
9533 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
9534 if (arg == error_mark_node)
9537 /* Simple cases: Value already set, does match or doesn't. */
9538 if (targ != NULL_TREE && same_type_p (targ, arg))
9543 /* Make sure that ARG is not a variable-sized array. (Note
9544 that were talking about variable-sized arrays (like
9545 `int[n]'), rather than arrays of unknown size (like
9546 `int[]').) We'll get very confused by such a type since
9547 the bound of the array will not be computable in an
9548 instantiation. Besides, such types are not allowed in
9549 ISO C++, so we can do as we please here. */
9550 if (variably_modified_type_p (arg))
9554 TREE_VEC_ELT (targs, idx) = arg;
9557 case TEMPLATE_PARM_INDEX:
9558 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9560 if (TEMPLATE_PARM_LEVEL (parm)
9561 != template_decl_level (tparm))
9562 /* The PARM is not one we're trying to unify. Just check
9563 to see if it matches ARG. */
9564 return !(TREE_CODE (arg) == TREE_CODE (parm)
9565 && cp_tree_equal (parm, arg));
9567 idx = TEMPLATE_PARM_IDX (parm);
9568 targ = TREE_VEC_ELT (targs, idx);
9571 return !cp_tree_equal (targ, arg);
9573 /* [temp.deduct.type] If, in the declaration of a function template
9574 with a non-type template-parameter, the non-type
9575 template-parameter is used in an expression in the function
9576 parameter-list and, if the corresponding template-argument is
9577 deduced, the template-argument type shall match the type of the
9578 template-parameter exactly, except that a template-argument
9579 deduced from an array bound may be of any integral type.
9580 The non-type parameter might use already deduced type parameters. */
9581 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
9582 if (!TREE_TYPE (arg))
9583 /* Template-parameter dependent expression. Just accept it for now.
9584 It will later be processed in convert_template_argument. */
9586 else if (same_type_p (TREE_TYPE (arg), tparm))
9588 else if ((strict & UNIFY_ALLOW_INTEGER)
9589 && (TREE_CODE (tparm) == INTEGER_TYPE
9590 || TREE_CODE (tparm) == BOOLEAN_TYPE))
9592 else if (uses_template_parms (tparm))
9593 /* We haven't deduced the type of this parameter yet. Try again
9599 TREE_VEC_ELT (targs, idx) = arg;
9604 if (TREE_CODE (arg) != POINTER_TYPE)
9607 /* [temp.deduct.call]
9609 A can be another pointer or pointer to member type that can
9610 be converted to the deduced A via a qualification
9611 conversion (_conv.qual_).
9613 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
9614 This will allow for additional cv-qualification of the
9615 pointed-to types if appropriate. */
9617 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
9618 /* The derived-to-base conversion only persists through one
9619 level of pointers. */
9620 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
9622 return unify (tparms, targs, TREE_TYPE (parm),
9623 TREE_TYPE (arg), strict);
9626 case REFERENCE_TYPE:
9627 if (TREE_CODE (arg) != REFERENCE_TYPE)
9629 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9630 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9633 if (TREE_CODE (arg) != ARRAY_TYPE)
9635 if ((TYPE_DOMAIN (parm) == NULL_TREE)
9636 != (TYPE_DOMAIN (arg) == NULL_TREE))
9638 if (TYPE_DOMAIN (parm) != NULL_TREE
9639 && unify (tparms, targs, TYPE_DOMAIN (parm),
9640 TYPE_DOMAIN (arg), UNIFY_ALLOW_NONE) != 0)
9642 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9643 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9651 if (TREE_CODE (arg) != TREE_CODE (parm))
9654 if (TREE_CODE (parm) == INTEGER_TYPE
9655 && TREE_CODE (TYPE_MAX_VALUE (parm)) != INTEGER_CST)
9657 if (TYPE_MIN_VALUE (parm) && TYPE_MIN_VALUE (arg)
9658 && unify (tparms, targs, TYPE_MIN_VALUE (parm),
9659 TYPE_MIN_VALUE (arg), UNIFY_ALLOW_INTEGER))
9661 if (TYPE_MAX_VALUE (parm) && TYPE_MAX_VALUE (arg)
9662 && unify (tparms, targs, TYPE_MAX_VALUE (parm),
9663 TYPE_MAX_VALUE (arg),
9664 UNIFY_ALLOW_INTEGER | UNIFY_ALLOW_MAX_CORRECTION))
9667 /* We have already checked cv-qualification at the top of the
9669 else if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
9672 /* As far as unification is concerned, this wins. Later checks
9673 will invalidate it if necessary. */
9676 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
9677 /* Type INTEGER_CST can come from ordinary constant template args. */
9679 while (TREE_CODE (arg) == NOP_EXPR)
9680 arg = TREE_OPERAND (arg, 0);
9682 if (TREE_CODE (arg) != INTEGER_CST)
9684 return !tree_int_cst_equal (parm, arg);
9689 if (TREE_CODE (arg) != TREE_VEC)
9691 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
9693 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
9694 if (unify (tparms, targs,
9695 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
9703 if (TREE_CODE (arg) != TREE_CODE (parm))
9706 if (TYPE_PTRMEMFUNC_P (parm))
9708 if (!TYPE_PTRMEMFUNC_P (arg))
9711 return unify (tparms, targs,
9712 TYPE_PTRMEMFUNC_FN_TYPE (parm),
9713 TYPE_PTRMEMFUNC_FN_TYPE (arg),
9717 if (CLASSTYPE_TEMPLATE_INFO (parm))
9721 if (strict_in & UNIFY_ALLOW_DERIVED)
9723 /* First, we try to unify the PARM and ARG directly. */
9724 t = try_class_unification (tparms, targs,
9729 /* Fallback to the special case allowed in
9732 If P is a class, and P has the form
9733 template-id, then A can be a derived class of
9734 the deduced A. Likewise, if P is a pointer to
9735 a class of the form template-id, A can be a
9736 pointer to a derived class pointed to by the
9738 t = get_template_base (tparms, targs,
9741 if (! t || t == error_mark_node)
9745 else if (CLASSTYPE_TEMPLATE_INFO (arg)
9746 && (CLASSTYPE_TI_TEMPLATE (parm)
9747 == CLASSTYPE_TI_TEMPLATE (arg)))
9748 /* Perhaps PARM is something like S<U> and ARG is S<int>.
9749 Then, we should unify `int' and `U'. */
9752 /* There's no chance of unification succeeding. */
9755 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
9756 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
9758 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
9764 if (TREE_CODE (arg) != TREE_CODE (parm))
9767 if (unify (tparms, targs, TREE_TYPE (parm),
9768 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
9770 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
9771 TYPE_ARG_TYPES (arg), 1,
9772 DEDUCE_EXACT, 0, -1);
9775 if (TREE_CODE (arg) != OFFSET_TYPE)
9777 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
9778 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
9780 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9784 if (DECL_TEMPLATE_PARM_P (parm))
9785 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
9786 if (arg != decl_constant_value (parm))
9791 /* Matched cases are handled by the ARG == PARM test above. */
9795 if (tree_int_cst_equal (TREE_OPERAND (parm, 1), integer_one_node)
9796 && (strict_in & UNIFY_ALLOW_MAX_CORRECTION))
9798 /* We handle this case specially, since it comes up with
9799 arrays. In particular, something like:
9801 template <int N> void f(int (&x)[N]);
9803 Here, we are trying to unify the range type, which
9804 looks like [0 ... (N - 1)]. */
9806 t1 = TREE_OPERAND (parm, 0);
9807 t2 = TREE_OPERAND (parm, 1);
9809 t = fold (build (PLUS_EXPR, integer_type_node, arg, t2));
9811 return unify (tparms, targs, t1, t, strict);
9813 /* else fall through */
9816 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (parm))))
9819 /* We're looking at an expression. This can happen with
9823 void foo(S<I>, S<I + 2>);
9825 This is a "nondeduced context":
9829 The nondeduced contexts are:
9831 --A type that is a template-id in which one or more of
9832 the template-arguments is an expression that references
9833 a template-parameter.
9835 In these cases, we assume deduction succeeded, but don't
9836 actually infer any unifications. */
9838 if (!uses_template_parms (parm)
9839 && !template_args_equal (parm, arg))
9845 sorry ("use of `%s' in template type unification",
9846 tree_code_name [(int) TREE_CODE (parm)]);
9852 /* Called if RESULT is explicitly instantiated, or is a member of an
9853 explicitly instantiated class, or if using -frepo and the
9854 instantiation of RESULT has been assigned to this file. */
9857 mark_decl_instantiated (tree result, int extern_p)
9859 /* We used to set this unconditionally; we moved that to
9860 do_decl_instantiation so it wouldn't get set on members of
9861 explicit class template instantiations. But we still need to set
9862 it here for the 'extern template' case in order to suppress
9863 implicit instantiations. */
9865 SET_DECL_EXPLICIT_INSTANTIATION (result);
9867 /* If this entity has already been written out, it's too late to
9868 make any modifications. */
9869 if (TREE_ASM_WRITTEN (result))
9872 if (TREE_CODE (result) != FUNCTION_DECL)
9873 /* The TREE_PUBLIC flag for function declarations will have been
9874 set correctly by tsubst. */
9875 TREE_PUBLIC (result) = 1;
9877 /* This might have been set by an earlier implicit instantiation. */
9878 DECL_COMDAT (result) = 0;
9882 DECL_INTERFACE_KNOWN (result) = 1;
9883 DECL_NOT_REALLY_EXTERN (result) = 1;
9885 /* Always make artificials weak. */
9886 if (DECL_ARTIFICIAL (result) && flag_weak)
9887 comdat_linkage (result);
9888 /* For WIN32 we also want to put explicit instantiations in
9889 linkonce sections. */
9890 else if (TREE_PUBLIC (result))
9891 maybe_make_one_only (result);
9894 if (TREE_CODE (result) == FUNCTION_DECL)
9898 /* Given two function templates PAT1 and PAT2, return:
9900 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
9902 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
9903 -1 if PAT2 is more specialized than PAT1.
9904 0 if neither is more specialized.
9906 LEN is passed through to fn_type_unification. */
9909 more_specialized (tree pat1, tree pat2, int deduce, int len)
9914 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
9915 NULL_TREE, 0, deduce, len);
9919 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
9920 NULL_TREE, 0, deduce, len);
9927 /* Given two class template specialization list nodes PAT1 and PAT2, return:
9929 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
9930 -1 if PAT2 is more specialized than PAT1.
9931 0 if neither is more specialized.
9933 FULL_ARGS is the full set of template arguments that triggers this
9934 partial ordering. */
9937 more_specialized_class (tree pat1, tree pat2, tree full_args)
9942 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
9943 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
9947 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
9948 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
9955 /* Return the template arguments that will produce the function signature
9956 DECL from the function template FN, with the explicit template
9957 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
9958 also match. Return NULL_TREE if no satisfactory arguments could be
9959 found. DEDUCE and LEN are passed through to fn_type_unification. */
9962 get_bindings_real (tree fn,
9969 int ntparms = DECL_NTPARMS (fn);
9970 tree targs = make_tree_vec (ntparms);
9972 tree decl_arg_types;
9975 /* Substitute the explicit template arguments into the type of DECL.
9976 The call to fn_type_unification will handle substitution into the
9978 decl_type = TREE_TYPE (decl);
9979 if (explicit_args && uses_template_parms (decl_type))
9982 tree converted_args;
9984 if (DECL_TEMPLATE_INFO (decl))
9985 tmpl = DECL_TI_TEMPLATE (decl);
9987 /* We can get here for some invalid specializations. */
9991 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
9992 explicit_args, NULL_TREE,
9993 tf_none, /*require_all_arguments=*/0));
9994 if (converted_args == error_mark_node)
9997 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
9998 if (decl_type == error_mark_node)
10002 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10003 /* Never do unification on the 'this' parameter. */
10004 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10005 decl_arg_types = TREE_CHAIN (decl_arg_types);
10007 i = fn_type_unification (fn, explicit_args, targs,
10009 (check_rettype || DECL_CONV_FN_P (fn)
10010 ? TREE_TYPE (decl_type) : NULL_TREE),
10019 /* For most uses, we want to check the return type. */
10022 get_bindings (tree fn, tree decl, tree explicit_args)
10024 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10027 /* But for resolve_overloaded_unification, we only care about the parameter
10031 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10033 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10036 /* Return the innermost template arguments that, when applied to a
10037 template specialization whose innermost template parameters are
10038 TPARMS, and whose specialization arguments are PARMS, yield the
10041 For example, suppose we have:
10043 template <class T, class U> struct S {};
10044 template <class T> struct S<T*, int> {};
10046 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10047 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10048 int}. The resulting vector will be {double}, indicating that `T'
10049 is bound to `double'. */
10052 get_class_bindings (tree tparms, tree parms, tree args)
10054 int i, ntparms = TREE_VEC_LENGTH (tparms);
10055 tree vec = make_tree_vec (ntparms);
10057 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10061 for (i = 0; i < ntparms; ++i)
10062 if (! TREE_VEC_ELT (vec, i))
10065 if (verify_class_unification (vec, parms, args))
10071 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10072 Pick the most specialized template, and return the corresponding
10073 instantiation, or if there is no corresponding instantiation, the
10074 template itself. If there is no most specialized template,
10075 error_mark_node is returned. If there are no templates at all,
10076 NULL_TREE is returned. */
10079 most_specialized_instantiation (tree instantiations)
10084 if (!instantiations)
10087 champ = instantiations;
10088 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10090 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10098 fn = TREE_CHAIN (fn);
10100 return error_mark_node;
10106 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10108 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10111 return error_mark_node;
10114 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10117 /* Return the most specialized of the list of templates in FNS that can
10118 produce an instantiation matching DECL, given the explicit template
10119 arguments EXPLICIT_ARGS. */
10122 most_specialized (tree fns, tree decl, tree explicit_args)
10124 tree candidates = NULL_TREE;
10127 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10129 tree candidate = TREE_VALUE (fn);
10131 args = get_bindings (candidate, decl, explicit_args);
10133 candidates = tree_cons (NULL_TREE, candidate, candidates);
10136 return most_specialized_instantiation (candidates);
10139 /* If DECL is a specialization of some template, return the most
10140 general such template. Otherwise, returns NULL_TREE.
10142 For example, given:
10144 template <class T> struct S { template <class U> void f(U); };
10146 if TMPL is `template <class U> void S<int>::f(U)' this will return
10147 the full template. This function will not trace past partial
10148 specializations, however. For example, given in addition:
10150 template <class T> struct S<T*> { template <class U> void f(U); };
10152 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10153 `template <class T> template <class U> S<T*>::f(U)'. */
10156 most_general_template (tree decl)
10158 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10159 an immediate specialization. */
10160 if (TREE_CODE (decl) == FUNCTION_DECL)
10162 if (DECL_TEMPLATE_INFO (decl)) {
10163 decl = DECL_TI_TEMPLATE (decl);
10165 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10166 template friend. */
10167 if (TREE_CODE (decl) != TEMPLATE_DECL)
10173 /* Look for more and more general templates. */
10174 while (DECL_TEMPLATE_INFO (decl))
10176 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10177 (See cp-tree.h for details.) */
10178 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10181 if (CLASS_TYPE_P (TREE_TYPE (decl))
10182 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10185 /* Stop if we run into an explicitly specialized class template. */
10186 if (!DECL_NAMESPACE_SCOPE_P (decl)
10187 && DECL_CONTEXT (decl)
10188 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10191 decl = DECL_TI_TEMPLATE (decl);
10197 /* Return the most specialized of the class template specializations
10198 of TMPL which can produce an instantiation matching ARGS, or
10199 error_mark_node if the choice is ambiguous. */
10202 most_specialized_class (tree tmpl, tree args)
10204 tree list = NULL_TREE;
10209 tmpl = most_general_template (tmpl);
10210 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10213 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10216 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10217 TREE_TYPE (list) = TREE_TYPE (t);
10226 t = TREE_CHAIN (t);
10227 for (; t; t = TREE_CHAIN (t))
10229 fate = more_specialized_class (champ, t, args);
10236 t = TREE_CHAIN (t);
10238 return error_mark_node;
10244 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10246 fate = more_specialized_class (champ, t, args);
10248 return error_mark_node;
10254 /* Explicitly instantiate DECL. */
10257 do_decl_instantiation (tree decl, tree storage)
10259 tree result = NULL_TREE;
10263 /* An error occurred, for which grokdeclarator has already issued
10264 an appropriate message. */
10266 else if (! DECL_LANG_SPECIFIC (decl))
10268 error ("explicit instantiation of non-template `%#D'", decl);
10271 else if (TREE_CODE (decl) == VAR_DECL)
10273 /* There is an asymmetry here in the way VAR_DECLs and
10274 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10275 the latter, the DECL we get back will be marked as a
10276 template instantiation, and the appropriate
10277 DECL_TEMPLATE_INFO will be set up. This does not happen for
10278 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10279 should handle VAR_DECLs as it currently handles
10281 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10282 if (!result || TREE_CODE (result) != VAR_DECL)
10284 error ("no matching template for `%D' found", decl);
10288 else if (TREE_CODE (decl) != FUNCTION_DECL)
10290 error ("explicit instantiation of `%#D'", decl);
10296 /* Check for various error cases. Note that if the explicit
10297 instantiation is valid the RESULT will currently be marked as an
10298 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10299 until we get here. */
10301 if (DECL_TEMPLATE_SPECIALIZATION (result))
10303 /* DR 259 [temp.spec].
10305 Both an explicit instantiation and a declaration of an explicit
10306 specialization shall not appear in a program unless the explicit
10307 instantiation follows a declaration of the explicit specialization.
10309 For a given set of template parameters, if an explicit
10310 instantiation of a template appears after a declaration of an
10311 explicit specialization for that template, the explicit
10312 instantiation has no effect. */
10315 else if (DECL_EXPLICIT_INSTANTIATION (result))
10319 No program shall explicitly instantiate any template more
10322 We check DECL_INTERFACE_KNOWN so as not to complain when the first
10323 instantiation was `extern' and the second is not, and EXTERN_P for
10324 the opposite case. If -frepo, chances are we already got marked
10325 as an explicit instantiation because of the repo file. */
10326 if (DECL_INTERFACE_KNOWN (result) && !extern_p && !flag_use_repository)
10327 pedwarn ("duplicate explicit instantiation of `%#D'", result);
10329 /* If we've already instantiated the template, just return now. */
10330 if (DECL_INTERFACE_KNOWN (result))
10333 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10335 error ("no matching template for `%D' found", result);
10338 else if (!DECL_TEMPLATE_INFO (result))
10340 pedwarn ("explicit instantiation of non-template `%#D'", result);
10344 if (flag_external_templates)
10347 if (storage == NULL_TREE)
10349 else if (storage == ridpointers[(int) RID_EXTERN])
10351 if (pedantic && !in_system_header)
10352 pedwarn ("ISO C++ forbids the use of `extern' on explicit instantiations");
10356 error ("storage class `%D' applied to template instantiation",
10359 SET_DECL_EXPLICIT_INSTANTIATION (result);
10360 mark_decl_instantiated (result, extern_p);
10361 repo_template_instantiated (result, extern_p);
10363 instantiate_decl (result, /*defer_ok=*/1);
10367 mark_class_instantiated (tree t, int extern_p)
10369 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10370 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10371 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10372 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10375 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10376 rest_of_type_compilation (t, 1);
10380 /* Called from do_type_instantiation through binding_table_foreach to
10381 do recursive instantiation for the type bound in ENTRY. */
10383 bt_instantiate_type_proc (binding_entry entry, void *data)
10385 tree storage = *(tree *) data;
10387 if (IS_AGGR_TYPE (entry->type)
10388 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10389 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10392 /* Perform an explicit instantiation of template class T. STORAGE, if
10393 non-null, is the RID for extern, inline or static. COMPLAIN is
10394 nonzero if this is called from the parser, zero if called recursively,
10395 since the standard is unclear (as detailed below). */
10398 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10404 if (TREE_CODE (t) == TYPE_DECL)
10407 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10409 error ("explicit instantiation of non-template type `%T'", t);
10415 /* With -fexternal-templates, explicit instantiations are treated the same
10416 as implicit ones. */
10417 if (flag_external_templates)
10420 if (!COMPLETE_TYPE_P (t))
10422 if (complain & tf_error)
10423 error ("explicit instantiation of `%#T' before definition of template",
10428 if (storage != NULL_TREE)
10430 if (pedantic && !in_system_header)
10431 pedwarn("ISO C++ forbids the use of `%s' on explicit instantiations",
10432 IDENTIFIER_POINTER (storage));
10434 if (storage == ridpointers[(int) RID_INLINE])
10436 else if (storage == ridpointers[(int) RID_EXTERN])
10438 else if (storage == ridpointers[(int) RID_STATIC])
10442 error ("storage class `%D' applied to template instantiation",
10448 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10450 /* DR 259 [temp.spec].
10452 Both an explicit instantiation and a declaration of an explicit
10453 specialization shall not appear in a program unless the explicit
10454 instantiation follows a declaration of the explicit specialization.
10456 For a given set of template parameters, if an explicit
10457 instantiation of a template appears after a declaration of an
10458 explicit specialization for that template, the explicit
10459 instantiation has no effect. */
10462 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10466 No program shall explicitly instantiate any template more
10469 If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation
10470 was `extern'. If EXTERN_P then the second is. If -frepo, chances
10471 are we already got marked as an explicit instantiation because of the
10472 repo file. All these cases are OK. */
10473 if (!CLASSTYPE_INTERFACE_ONLY (t) && !extern_p && !flag_use_repository
10474 && (complain & tf_error))
10475 pedwarn ("duplicate explicit instantiation of `%#T'", t);
10477 /* If we've already instantiated the template, just return now. */
10478 if (!CLASSTYPE_INTERFACE_ONLY (t))
10482 mark_class_instantiated (t, extern_p);
10483 repo_template_instantiated (t, extern_p);
10491 /* In contrast to implicit instantiation, where only the
10492 declarations, and not the definitions, of members are
10493 instantiated, we have here:
10497 The explicit instantiation of a class template specialization
10498 implies the instantiation of all of its members not
10499 previously explicitly specialized in the translation unit
10500 containing the explicit instantiation.
10502 Of course, we can't instantiate member template classes, since
10503 we don't have any arguments for them. Note that the standard
10504 is unclear on whether the instantiation of the members are
10505 *explicit* instantiations or not. We choose to be generous,
10506 and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow
10507 the explicit instantiation of a class where some of the members
10508 have no definition in the current translation unit. */
10511 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
10512 if (TREE_CODE (tmp) == FUNCTION_DECL
10513 && DECL_TEMPLATE_INSTANTIATION (tmp))
10515 mark_decl_instantiated (tmp, extern_p);
10516 repo_template_instantiated (tmp, extern_p);
10518 instantiate_decl (tmp, /*defer_ok=*/1);
10521 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
10522 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
10524 mark_decl_instantiated (tmp, extern_p);
10525 repo_template_instantiated (tmp, extern_p);
10527 instantiate_decl (tmp, /*defer_ok=*/1);
10530 if (CLASSTYPE_NESTED_UTDS (t))
10531 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
10532 bt_instantiate_type_proc, &storage);
10536 /* Given a function DECL, which is a specialization of TMPL, modify
10537 DECL to be a re-instantiation of TMPL with the same template
10538 arguments. TMPL should be the template into which tsubst'ing
10539 should occur for DECL, not the most general template.
10541 One reason for doing this is a scenario like this:
10544 void f(const T&, int i);
10546 void g() { f(3, 7); }
10549 void f(const T& t, const int i) { }
10551 Note that when the template is first instantiated, with
10552 instantiate_template, the resulting DECL will have no name for the
10553 first parameter, and the wrong type for the second. So, when we go
10554 to instantiate the DECL, we regenerate it. */
10557 regenerate_decl_from_template (tree decl, tree tmpl)
10559 /* The most general version of TMPL. */
10561 /* The arguments used to instantiate DECL, from the most general
10568 args = DECL_TI_ARGS (decl);
10569 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
10571 /* Unregister the specialization so that when we tsubst we will not
10572 just return DECL. We don't have to unregister DECL from TMPL
10573 because if would only be registered there if it were a partial
10574 instantiation of a specialization, which it isn't: it's a full
10576 gen_tmpl = most_general_template (tmpl);
10577 unregistered = reregister_specialization (decl, gen_tmpl,
10578 /*new_spec=*/NULL_TREE);
10580 /* If the DECL was not unregistered then something peculiar is
10581 happening: we created a specialization but did not call
10582 register_specialization for it. */
10583 my_friendly_assert (unregistered, 0);
10585 /* Make sure that we can see identifiers, and compute access
10587 push_access_scope (decl);
10589 /* Do the substitution to get the new declaration. */
10590 new_decl = tsubst (code_pattern, args, tf_error, NULL_TREE);
10592 if (TREE_CODE (decl) == VAR_DECL)
10594 /* Set up DECL_INITIAL, since tsubst doesn't. */
10595 if (!DECL_INITIALIZED_IN_CLASS_P (decl))
10596 DECL_INITIAL (new_decl) =
10597 tsubst_expr (DECL_INITIAL (code_pattern), args,
10598 tf_error, DECL_TI_TEMPLATE (decl));
10600 else if (TREE_CODE (decl) == FUNCTION_DECL)
10602 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
10604 DECL_INITIAL (new_decl) = error_mark_node;
10605 /* And don't complain about a duplicate definition. */
10606 DECL_INITIAL (decl) = NULL_TREE;
10609 pop_access_scope (decl);
10611 /* The immediate parent of the new template is still whatever it was
10612 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
10613 general template. We also reset the DECL_ASSEMBLER_NAME since
10614 tsubst always calculates the name as if the function in question
10615 were really a template instance, and sometimes, with friend
10616 functions, this is not so. See tsubst_friend_function for
10618 DECL_TI_TEMPLATE (new_decl) = DECL_TI_TEMPLATE (decl);
10619 COPY_DECL_ASSEMBLER_NAME (decl, new_decl);
10620 COPY_DECL_RTL (decl, new_decl);
10621 DECL_USE_TEMPLATE (new_decl) = DECL_USE_TEMPLATE (decl);
10623 /* Call duplicate decls to merge the old and new declarations. */
10624 duplicate_decls (new_decl, decl);
10626 /* Now, re-register the specialization. */
10627 register_specialization (decl, gen_tmpl, args);
10630 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
10631 substituted to get DECL. */
10634 template_for_substitution (tree decl)
10636 tree tmpl = DECL_TI_TEMPLATE (decl);
10638 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
10639 for the instantiation. This is not always the most general
10640 template. Consider, for example:
10643 struct S { template <class U> void f();
10644 template <> void f<int>(); };
10646 and an instantiation of S<double>::f<int>. We want TD to be the
10647 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
10648 while (/* An instantiation cannot have a definition, so we need a
10649 more general template. */
10650 DECL_TEMPLATE_INSTANTIATION (tmpl)
10651 /* We must also deal with friend templates. Given:
10653 template <class T> struct S {
10654 template <class U> friend void f() {};
10657 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
10658 so far as the language is concerned, but that's still
10659 where we get the pattern for the instantiation from. On
10660 other hand, if the definition comes outside the class, say:
10662 template <class T> struct S {
10663 template <class U> friend void f();
10665 template <class U> friend void f() {}
10667 we don't need to look any further. That's what the check for
10668 DECL_INITIAL is for. */
10669 || (TREE_CODE (decl) == FUNCTION_DECL
10670 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
10671 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
10673 /* The present template, TD, should not be a definition. If it
10674 were a definition, we should be using it! Note that we
10675 cannot restructure the loop to just keep going until we find
10676 a template with a definition, since that might go too far if
10677 a specialization was declared, but not defined. */
10678 my_friendly_assert (!(TREE_CODE (decl) == VAR_DECL
10679 && !DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl))),
10682 /* Fetch the more general template. */
10683 tmpl = DECL_TI_TEMPLATE (tmpl);
10689 /* Produce the definition of D, a _DECL generated from a template. If
10690 DEFER_OK is nonzero, then we don't have to actually do the
10691 instantiation now; we just have to do it sometime. */
10694 instantiate_decl (tree d, int defer_ok)
10696 tree tmpl = DECL_TI_TEMPLATE (d);
10703 int pattern_defined;
10705 location_t saved_loc = input_location;
10707 /* This function should only be used to instantiate templates for
10708 functions and static member variables. */
10709 my_friendly_assert (TREE_CODE (d) == FUNCTION_DECL
10710 || TREE_CODE (d) == VAR_DECL, 0);
10712 /* Variables are never deferred; if instantiation is required, they
10713 are instantiated right away. That allows for better code in the
10714 case that an expression refers to the value of the variable --
10715 if the variable has a constant value the referring expression can
10716 take advantage of that fact. */
10717 if (TREE_CODE (d) == VAR_DECL)
10720 /* Don't instantiate cloned functions. Instead, instantiate the
10721 functions they cloned. */
10722 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
10723 d = DECL_CLONED_FUNCTION (d);
10725 if (DECL_TEMPLATE_INSTANTIATED (d))
10726 /* D has already been instantiated. It might seem reasonable to
10727 check whether or not D is an explicit instantiation, and, if so,
10728 stop here. But when an explicit instantiation is deferred
10729 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
10730 is set, even though we still need to do the instantiation. */
10733 /* If we already have a specialization of this declaration, then
10734 there's no reason to instantiate it. Note that
10735 retrieve_specialization gives us both instantiations and
10736 specializations, so we must explicitly check
10737 DECL_TEMPLATE_SPECIALIZATION. */
10738 gen_tmpl = most_general_template (tmpl);
10739 gen_args = DECL_TI_ARGS (d);
10740 spec = retrieve_specialization (gen_tmpl, gen_args);
10741 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
10744 /* This needs to happen before any tsubsting. */
10745 if (! push_tinst_level (d))
10748 timevar_push (TV_PARSE);
10750 /* We may be in the middle of deferred access check. Disable
10752 push_deferring_access_checks (dk_no_deferred);
10754 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
10755 for the instantiation. */
10756 td = template_for_substitution (d);
10757 code_pattern = DECL_TEMPLATE_RESULT (td);
10759 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
10760 || DECL_TEMPLATE_SPECIALIZATION (td))
10761 /* In the case of a friend template whose definition is provided
10762 outside the class, we may have too many arguments. Drop the
10763 ones we don't need. The same is true for specializations. */
10764 args = get_innermost_template_args
10765 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
10769 if (TREE_CODE (d) == FUNCTION_DECL)
10770 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
10772 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
10774 input_location = DECL_SOURCE_LOCATION (d);
10776 if (pattern_defined)
10778 /* Let the repository code that this template definition is
10781 The repository doesn't need to know about cloned functions
10782 because they never actually show up in the object file. It
10783 does need to know about the clones; those are the symbols
10784 that the linker will be emitting error messages about. */
10785 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (d)
10786 || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (d))
10790 for (t = TREE_CHAIN (d);
10791 t && DECL_CLONED_FUNCTION_P (t);
10792 t = TREE_CHAIN (t))
10793 repo_template_used (t);
10796 repo_template_used (d);
10798 if (flag_external_templates && ! DECL_INTERFACE_KNOWN (d))
10800 if (flag_alt_external_templates)
10802 if (interface_unknown)
10803 warn_if_unknown_interface (d);
10805 else if (DECL_INTERFACE_KNOWN (code_pattern))
10807 DECL_INTERFACE_KNOWN (d) = 1;
10808 DECL_NOT_REALLY_EXTERN (d) = ! DECL_EXTERNAL (code_pattern);
10811 warn_if_unknown_interface (code_pattern);
10815 import_export_decl (d);
10820 /* Recheck the substitutions to obtain any warning messages
10821 about ignoring cv qualifiers. */
10822 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
10823 tree type = TREE_TYPE (gen);
10825 /* Make sure that we can see identifiers, and compute access
10826 correctly. D is already the target FUNCTION_DECL with the
10828 push_access_scope (d);
10830 if (TREE_CODE (gen) == FUNCTION_DECL)
10832 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
10833 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
10834 tf_error | tf_warning, d);
10835 /* Don't simply tsubst the function type, as that will give
10836 duplicate warnings about poor parameter qualifications.
10837 The function arguments are the same as the decl_arguments
10838 without the top level cv qualifiers. */
10839 type = TREE_TYPE (type);
10841 tsubst (type, gen_args, tf_error | tf_warning, d);
10843 pop_access_scope (d);
10846 if (TREE_CODE (d) == VAR_DECL && DECL_INITIALIZED_IN_CLASS_P (d)
10847 && DECL_INITIAL (d) == NULL_TREE)
10848 /* We should have set up DECL_INITIAL in instantiate_class_template. */
10850 /* Reject all external templates except inline functions. */
10851 else if (DECL_INTERFACE_KNOWN (d)
10852 && ! DECL_NOT_REALLY_EXTERN (d)
10853 && ! (TREE_CODE (d) == FUNCTION_DECL
10854 && DECL_INLINE (d)))
10856 /* Defer all other templates, unless we have been explicitly
10857 forbidden from doing so. We restore the source position here
10858 because it's used by add_pending_template. */
10859 else if (! pattern_defined || defer_ok)
10861 input_location = saved_loc;
10863 if (at_eof && !pattern_defined
10864 && DECL_EXPLICIT_INSTANTIATION (d))
10867 The definition of a non-exported function template, a
10868 non-exported member function template, or a non-exported
10869 member function or static data member of a class template
10870 shall be present in every translation unit in which it is
10871 explicitly instantiated. */
10873 ("explicit instantiation of `%D' but no definition available", d);
10875 add_pending_template (d);
10879 need_push = !global_bindings_p ();
10881 push_to_top_level ();
10883 /* Regenerate the declaration in case the template has been modified
10884 by a subsequent redeclaration. */
10885 regenerate_decl_from_template (d, td);
10887 /* We already set the file and line above. Reset them now in case
10888 they changed as a result of calling
10889 regenerate_decl_from_template. */
10890 input_location = DECL_SOURCE_LOCATION (d);
10892 if (TREE_CODE (d) == VAR_DECL)
10894 /* Clear out DECL_RTL; whatever was there before may not be right
10895 since we've reset the type of the declaration. */
10896 SET_DECL_RTL (d, NULL_RTX);
10898 DECL_IN_AGGR_P (d) = 0;
10899 import_export_decl (d);
10900 DECL_EXTERNAL (d) = ! DECL_NOT_REALLY_EXTERN (d);
10902 if (DECL_EXTERNAL (d))
10904 /* The fact that this code is executing indicates that:
10906 (1) D is a template static data member, for which a
10907 definition is available.
10909 (2) An implicit or explicit instantiation has occurred.
10911 (3) We are not going to emit a definition of the static
10912 data member at this time.
10914 This situation is peculiar, but it occurs on platforms
10915 without weak symbols when performing an implicit
10916 instantiation. There, we cannot implicitly instantiate a
10917 defined static data member in more than one translation
10918 unit, so import_export_decl marks the declaration as
10919 external; we must rely on explicit instantiation. */
10923 /* Mark D as instantiated so that recursive calls to
10924 instantiate_decl do not try to instantiate it again. */
10925 DECL_TEMPLATE_INSTANTIATED (d) = 1;
10927 (!DECL_INITIALIZED_IN_CLASS_P (d)
10928 ? DECL_INITIAL (d) : NULL_TREE),
10932 else if (TREE_CODE (d) == FUNCTION_DECL)
10934 htab_t saved_local_specializations;
10939 /* Mark D as instantiated so that recursive calls to
10940 instantiate_decl do not try to instantiate it again. */
10941 DECL_TEMPLATE_INSTANTIATED (d) = 1;
10943 /* Save away the current list, in case we are instantiating one
10944 template from within the body of another. */
10945 saved_local_specializations = local_specializations;
10947 /* Set up the list of local specializations. */
10948 local_specializations = htab_create (37,
10949 hash_local_specialization,
10950 eq_local_specializations,
10953 /* Set up context. */
10954 import_export_decl (d);
10955 start_function (NULL_TREE, d, NULL_TREE, SF_PRE_PARSED);
10957 /* Create substitution entries for the parameters. */
10958 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
10959 tmpl_parm = DECL_ARGUMENTS (subst_decl);
10960 spec_parm = DECL_ARGUMENTS (d);
10961 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
10963 register_local_specialization (spec_parm, tmpl_parm);
10964 spec_parm = skip_artificial_parms_for (d, spec_parm);
10965 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
10969 register_local_specialization (spec_parm, tmpl_parm);
10970 tmpl_parm = TREE_CHAIN (tmpl_parm);
10971 spec_parm = TREE_CHAIN (spec_parm);
10973 my_friendly_assert (!spec_parm, 20020813);
10975 /* Substitute into the body of the function. */
10976 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
10977 tf_error | tf_warning, tmpl);
10979 /* We don't need the local specializations any more. */
10980 htab_delete (local_specializations);
10981 local_specializations = saved_local_specializations;
10983 /* Finish the function. */
10984 d = finish_function (0);
10985 expand_or_defer_fn (d);
10988 /* We're not deferring instantiation any more. */
10989 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
10992 pop_from_top_level ();
10995 input_location = saved_loc;
10996 pop_deferring_access_checks ();
10997 pop_tinst_level ();
10999 timevar_pop (TV_PARSE);
11004 /* Run through the list of templates that we wish we could
11005 instantiate, and instantiate any we can. */
11008 instantiate_pending_templates (void)
11011 tree last = NULL_TREE;
11012 int instantiated_something = 0;
11019 t = &pending_templates;
11022 tree instantiation = TREE_VALUE (*t);
11024 reopen_tinst_level (TREE_PURPOSE (*t));
11026 if (TYPE_P (instantiation))
11030 if (!COMPLETE_TYPE_P (instantiation))
11032 instantiate_class_template (instantiation);
11033 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11034 for (fn = TYPE_METHODS (instantiation);
11036 fn = TREE_CHAIN (fn))
11037 if (! DECL_ARTIFICIAL (fn))
11038 instantiate_decl (fn, /*defer_ok=*/0);
11039 if (COMPLETE_TYPE_P (instantiation))
11041 instantiated_something = 1;
11046 if (COMPLETE_TYPE_P (instantiation))
11047 /* If INSTANTIATION has been instantiated, then we don't
11048 need to consider it again in the future. */
11049 *t = TREE_CHAIN (*t);
11053 t = &TREE_CHAIN (*t);
11058 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11059 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11061 instantiation = instantiate_decl (instantiation,
11063 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11065 instantiated_something = 1;
11070 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11071 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11072 /* If INSTANTIATION has been instantiated, then we don't
11073 need to consider it again in the future. */
11074 *t = TREE_CHAIN (*t);
11078 t = &TREE_CHAIN (*t);
11082 current_tinst_level = NULL_TREE;
11084 last_pending_template = last;
11086 while (reconsider);
11088 return instantiated_something;
11091 /* Substitute ARGVEC into T, which is a list of initializers for
11092 either base class or a non-static data member. The TREE_PURPOSEs
11093 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11094 instantiate_decl. */
11097 tsubst_initializer_list (tree t, tree argvec)
11099 tree inits = NULL_TREE;
11101 for (; t; t = TREE_CHAIN (t))
11107 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11109 decl = expand_member_init (decl);
11110 if (decl && !DECL_P (decl))
11111 in_base_initializer = 1;
11113 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11117 else if (TREE_CODE (init) == TREE_LIST)
11118 for (val = init; val; val = TREE_CHAIN (val))
11119 TREE_VALUE (val) = convert_from_reference (TREE_VALUE (val));
11120 else if (init != void_type_node)
11121 init = convert_from_reference (init);
11123 in_base_initializer = 0;
11127 init = build_tree_list (decl, init);
11128 TREE_CHAIN (init) = inits;
11135 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11138 set_current_access_from_decl (tree decl)
11140 if (TREE_PRIVATE (decl))
11141 current_access_specifier = access_private_node;
11142 else if (TREE_PROTECTED (decl))
11143 current_access_specifier = access_protected_node;
11145 current_access_specifier = access_public_node;
11148 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11149 is the instantiation (which should have been created with
11150 start_enum) and ARGS are the template arguments to use. */
11153 tsubst_enum (tree tag, tree newtag, tree args)
11157 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11162 decl = TREE_VALUE (e);
11163 /* Note that in a template enum, the TREE_VALUE is the
11164 CONST_DECL, not the corresponding INTEGER_CST. */
11165 value = tsubst_expr (DECL_INITIAL (decl),
11166 args, tf_error | tf_warning,
11169 /* Give this enumeration constant the correct access. */
11170 set_current_access_from_decl (decl);
11172 /* Actually build the enumerator itself. */
11173 build_enumerator (DECL_NAME (decl), value, newtag);
11176 finish_enum (newtag);
11177 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11178 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11181 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11182 its type -- but without substituting the innermost set of template
11183 arguments. So, innermost set of template parameters will appear in
11187 get_mostly_instantiated_function_type (tree decl)
11195 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11196 targs = DECL_TI_ARGS (decl);
11197 tparms = DECL_TEMPLATE_PARMS (tmpl);
11198 parm_depth = TMPL_PARMS_DEPTH (tparms);
11200 /* There should be as many levels of arguments as there are levels
11202 my_friendly_assert (parm_depth == TMPL_ARGS_DEPTH (targs), 0);
11204 fn_type = TREE_TYPE (tmpl);
11206 if (parm_depth == 1)
11207 /* No substitution is necessary. */
11214 /* Replace the innermost level of the TARGS with NULL_TREEs to
11215 let tsubst know not to substitute for those parameters. */
11216 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11217 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11218 SET_TMPL_ARGS_LEVEL (partial_args, i,
11219 TMPL_ARGS_LEVEL (targs, i));
11220 SET_TMPL_ARGS_LEVEL (partial_args,
11221 TMPL_ARGS_DEPTH (targs),
11222 make_tree_vec (DECL_NTPARMS (tmpl)));
11224 /* Make sure that we can see identifiers, and compute access
11225 correctly. We can just use the context of DECL for the
11226 partial substitution here. It depends only on outer template
11227 parameters, regardless of whether the innermost level is
11228 specialized or not. */
11229 push_access_scope (decl);
11231 /* Now, do the (partial) substitution to figure out the
11232 appropriate function type. */
11233 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11235 /* Substitute into the template parameters to obtain the real
11236 innermost set of parameters. This step is important if the
11237 innermost set of template parameters contains value
11238 parameters whose types depend on outer template parameters. */
11239 TREE_VEC_LENGTH (partial_args)--;
11240 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11242 pop_access_scope (decl);
11248 /* Return truthvalue if we're processing a template different from
11249 the last one involved in diagnostics. */
11251 problematic_instantiation_changed (void)
11253 return last_template_error_tick != tinst_level_tick;
11256 /* Remember current template involved in diagnostics. */
11258 record_last_problematic_instantiation (void)
11260 last_template_error_tick = tinst_level_tick;
11264 current_instantiation (void)
11266 return current_tinst_level;
11269 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11270 type. Return zero for ok, nonzero for disallowed. Issue error and
11271 warning messages under control of COMPLAIN. */
11274 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11276 if (INTEGRAL_TYPE_P (type))
11278 else if (POINTER_TYPE_P (type))
11280 else if (TYPE_PTR_TO_MEMBER_P (type))
11282 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11284 else if (TREE_CODE (type) == TYPENAME_TYPE)
11287 if (complain & tf_error)
11288 error ("`%#T' is not a valid type for a template constant parameter",
11293 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11294 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11297 dependent_type_p_r (tree type)
11303 A type is dependent if it is:
11305 -- a template parameter. */
11306 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11308 /* -- a qualified-id with a nested-name-specifier which contains a
11309 class-name that names a dependent type or whose unqualified-id
11310 names a dependent type. */
11311 if (TREE_CODE (type) == TYPENAME_TYPE)
11313 /* -- a cv-qualified type where the cv-unqualified type is
11315 type = TYPE_MAIN_VARIANT (type);
11316 /* -- a compound type constructed from any dependent type. */
11317 if (TYPE_PTR_TO_MEMBER_P (type))
11318 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11319 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11321 else if (TREE_CODE (type) == POINTER_TYPE
11322 || TREE_CODE (type) == REFERENCE_TYPE)
11323 return dependent_type_p (TREE_TYPE (type));
11324 else if (TREE_CODE (type) == FUNCTION_TYPE
11325 || TREE_CODE (type) == METHOD_TYPE)
11329 if (dependent_type_p (TREE_TYPE (type)))
11331 for (arg_type = TYPE_ARG_TYPES (type);
11333 arg_type = TREE_CHAIN (arg_type))
11334 if (dependent_type_p (TREE_VALUE (arg_type)))
11338 /* -- an array type constructed from any dependent type or whose
11339 size is specified by a constant expression that is
11340 value-dependent. */
11341 if (TREE_CODE (type) == ARRAY_TYPE)
11343 if (TYPE_DOMAIN (type)
11344 && ((value_dependent_expression_p
11345 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11346 || (type_dependent_expression_p
11347 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11349 return dependent_type_p (TREE_TYPE (type));
11351 /* -- a template-id in which either the template name is a template
11352 parameter or any of the template arguments is a dependent type or
11353 an expression that is type-dependent or value-dependent.
11355 This language seems somewhat confused; for example, it does not
11356 discuss template template arguments. Therefore, we use the
11357 definition for dependent template arguments in [temp.dep.temp]. */
11358 if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11359 && (dependent_template_id_p
11360 (CLASSTYPE_TI_TEMPLATE (type),
11361 CLASSTYPE_TI_ARGS (type))))
11363 else if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11365 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11366 expression is not type-dependent, then it should already been
11368 if (TREE_CODE (type) == TYPEOF_TYPE)
11370 /* The standard does not specifically mention types that are local
11371 to template functions or local classes, but they should be
11372 considered dependent too. For example:
11374 template <int I> void f() {
11379 The size of `E' cannot be known until the value of `I' has been
11380 determined. Therefore, `E' must be considered dependent. */
11381 scope = TYPE_CONTEXT (type);
11382 if (scope && TYPE_P (scope))
11383 return dependent_type_p (scope);
11384 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11385 return type_dependent_expression_p (scope);
11387 /* Other types are non-dependent. */
11391 /* Returns TRUE if TYPE is dependent, in the sense of
11392 [temp.dep.type]. */
11395 dependent_type_p (tree type)
11397 /* If there are no template parameters in scope, then there can't be
11398 any dependent types. */
11399 if (!processing_template_decl)
11402 /* If the type is NULL, we have not computed a type for the entity
11403 in question; in that case, the type is dependent. */
11407 /* Erroneous types can be considered non-dependent. */
11408 if (type == error_mark_node)
11411 /* If we have not already computed the appropriate value for TYPE,
11413 if (!TYPE_DEPENDENT_P_VALID (type))
11415 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11416 TYPE_DEPENDENT_P_VALID (type) = 1;
11419 return TYPE_DEPENDENT_P (type);
11422 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11425 dependent_scope_ref_p (tree expression, bool criterion (tree))
11430 my_friendly_assert (TREE_CODE (expression) == SCOPE_REF, 20030714);
11432 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11435 scope = TREE_OPERAND (expression, 0);
11436 name = TREE_OPERAND (expression, 1);
11440 An id-expression is type-dependent if it contains a
11441 nested-name-specifier that contains a class-name that names a
11443 /* The suggested resolution to Core Issue 2 implies that if the
11444 qualifying type is the current class, then we must peek
11447 && currently_open_class (scope)
11448 && !criterion (name))
11450 if (dependent_type_p (scope))
11456 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11457 [temp.dep.constexpr] */
11460 value_dependent_expression_p (tree expression)
11462 if (!processing_template_decl)
11465 /* A name declared with a dependent type. */
11466 if (TREE_CODE (expression) == IDENTIFIER_NODE
11467 || (DECL_P (expression)
11468 && type_dependent_expression_p (expression)))
11470 /* A non-type template parameter. */
11471 if ((TREE_CODE (expression) == CONST_DECL
11472 && DECL_TEMPLATE_PARM_P (expression))
11473 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11475 /* A constant with integral or enumeration type and is initialized
11476 with an expression that is value-dependent. */
11477 if (TREE_CODE (expression) == VAR_DECL
11478 && DECL_INITIAL (expression)
11479 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11480 && value_dependent_expression_p (DECL_INITIAL (expression)))
11482 /* These expressions are value-dependent if the type to which the
11483 cast occurs is dependent or the expression being casted is
11484 value-dependent. */
11485 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11486 || TREE_CODE (expression) == STATIC_CAST_EXPR
11487 || TREE_CODE (expression) == CONST_CAST_EXPR
11488 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11489 || TREE_CODE (expression) == CAST_EXPR)
11491 if (dependent_type_p (TREE_TYPE (expression)))
11493 /* A functional cast has a list of operands. */
11494 expression = TREE_OPERAND (expression, 0);
11495 if (TREE_CODE (expression) == TREE_LIST)
11499 if (value_dependent_expression_p (TREE_VALUE (expression)))
11501 expression = TREE_CHAIN (expression);
11503 while (expression);
11507 return value_dependent_expression_p (expression);
11509 /* A `sizeof' expression is value-dependent if the operand is
11511 if (TREE_CODE (expression) == SIZEOF_EXPR
11512 || TREE_CODE (expression) == ALIGNOF_EXPR)
11514 expression = TREE_OPERAND (expression, 0);
11515 if (TYPE_P (expression))
11516 return dependent_type_p (expression);
11517 return type_dependent_expression_p (expression);
11519 if (TREE_CODE (expression) == SCOPE_REF)
11520 return dependent_scope_ref_p (expression, value_dependent_expression_p);
11521 /* A constant expression is value-dependent if any subexpression is
11522 value-dependent. */
11523 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (expression))))
11525 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
11528 return (value_dependent_expression_p
11529 (TREE_OPERAND (expression, 0)));
11532 return ((value_dependent_expression_p
11533 (TREE_OPERAND (expression, 0)))
11534 || (value_dependent_expression_p
11535 (TREE_OPERAND (expression, 1))));
11539 for (i = 0; i < first_rtl_op (TREE_CODE (expression)); ++i)
11540 /* In some cases, some of the operands may be missing.
11541 (For example, in the case of PREDECREMENT_EXPR, the
11542 amount to increment by may be missing.) That doesn't
11543 make the expression dependent. */
11544 if (TREE_OPERAND (expression, i)
11545 && (value_dependent_expression_p
11546 (TREE_OPERAND (expression, i))))
11553 /* The expression is not value-dependent. */
11557 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11558 [temp.dep.expr]. */
11561 type_dependent_expression_p (tree expression)
11563 if (!processing_template_decl)
11566 if (expression == error_mark_node)
11569 /* An unresolved name is always dependent. */
11570 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11573 /* Some expression forms are never type-dependent. */
11574 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
11575 || TREE_CODE (expression) == SIZEOF_EXPR
11576 || TREE_CODE (expression) == ALIGNOF_EXPR
11577 || TREE_CODE (expression) == TYPEID_EXPR
11578 || TREE_CODE (expression) == DELETE_EXPR
11579 || TREE_CODE (expression) == VEC_DELETE_EXPR
11580 || TREE_CODE (expression) == THROW_EXPR)
11583 /* The types of these expressions depends only on the type to which
11584 the cast occurs. */
11585 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11586 || TREE_CODE (expression) == STATIC_CAST_EXPR
11587 || TREE_CODE (expression) == CONST_CAST_EXPR
11588 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11589 || TREE_CODE (expression) == CAST_EXPR)
11590 return dependent_type_p (TREE_TYPE (expression));
11592 /* The types of these expressions depends only on the type created
11593 by the expression. */
11594 if (TREE_CODE (expression) == NEW_EXPR
11595 || TREE_CODE (expression) == VEC_NEW_EXPR)
11597 /* For NEW_EXPR tree nodes created inside a template, either
11598 the object type itself or a TREE_LIST may appear as the
11600 tree type = TREE_OPERAND (expression, 1);
11601 if (TREE_CODE (type) == TREE_LIST)
11602 /* This is an array type. We need to check array dimensions
11604 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
11605 || value_dependent_expression_p
11606 (TREE_OPERAND (TREE_VALUE (type), 1));
11608 return dependent_type_p (type);
11611 if (TREE_CODE (expression) == SCOPE_REF
11612 && dependent_scope_ref_p (expression,
11613 type_dependent_expression_p))
11616 if (TREE_CODE (expression) == FUNCTION_DECL
11617 && DECL_LANG_SPECIFIC (expression)
11618 && DECL_TEMPLATE_INFO (expression)
11619 && (dependent_template_id_p
11620 (DECL_TI_TEMPLATE (expression),
11621 INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
11624 if (TREE_TYPE (expression) == unknown_type_node)
11626 if (TREE_CODE (expression) == ADDR_EXPR)
11627 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
11628 if (TREE_CODE (expression) == COMPONENT_REF)
11630 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
11632 expression = TREE_OPERAND (expression, 1);
11633 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11637 if (TREE_CODE (expression) == BASELINK)
11638 expression = BASELINK_FUNCTIONS (expression);
11639 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
11641 if (any_dependent_template_arguments_p
11642 (TREE_OPERAND (expression, 1)))
11644 expression = TREE_OPERAND (expression, 0);
11646 if (TREE_CODE (expression) == OVERLOAD)
11650 if (type_dependent_expression_p (OVL_CURRENT (expression)))
11652 expression = OVL_NEXT (expression);
11659 return (dependent_type_p (TREE_TYPE (expression)));
11662 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
11663 contains a type-dependent expression. */
11666 any_type_dependent_arguments_p (tree args)
11670 tree arg = TREE_VALUE (args);
11672 if (type_dependent_expression_p (arg))
11674 args = TREE_CHAIN (args);
11679 /* Returns TRUE if the ARG (a template argument) is dependent. */
11682 dependent_template_arg_p (tree arg)
11684 if (!processing_template_decl)
11687 if (TREE_CODE (arg) == TEMPLATE_DECL
11688 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11689 return dependent_template_p (arg);
11690 else if (TYPE_P (arg))
11691 return dependent_type_p (arg);
11693 return (type_dependent_expression_p (arg)
11694 || value_dependent_expression_p (arg));
11697 /* Returns true if ARGS (a collection of template arguments) contains
11698 any dependent arguments. */
11701 any_dependent_template_arguments_p (tree args)
11706 my_friendly_assert (TREE_CODE (args) == TREE_LIST
11707 || TREE_CODE (args) == TREE_VEC,
11710 if (TREE_CODE (args) == TREE_LIST)
11714 if (dependent_template_arg_p (TREE_VALUE (args)))
11716 args = TREE_CHAIN (args);
11722 for (i = 0; i < TREE_VEC_LENGTH (args); ++i)
11723 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
11730 /* Returns TRUE if the template TMPL is dependent. */
11733 dependent_template_p (tree tmpl)
11735 /* Template template parameters are dependent. */
11736 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
11737 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
11739 /* So are qualified names that have not been looked up. */
11740 if (TREE_CODE (tmpl) == SCOPE_REF)
11742 /* So are member templates of dependent classes. */
11743 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
11744 return dependent_type_p (DECL_CONTEXT (tmpl));
11748 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
11751 dependent_template_id_p (tree tmpl, tree args)
11753 return (dependent_template_p (tmpl)
11754 || any_dependent_template_arguments_p (args));
11757 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
11758 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
11759 can be found. Note that this function peers inside uninstantiated
11760 templates and therefore should be used only in extremely limited
11764 resolve_typename_type (tree type, bool only_current_p)
11771 my_friendly_assert (TREE_CODE (type) == TYPENAME_TYPE,
11774 scope = TYPE_CONTEXT (type);
11775 name = TYPE_IDENTIFIER (type);
11777 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
11778 it first before we can figure out what NAME refers to. */
11779 if (TREE_CODE (scope) == TYPENAME_TYPE)
11780 scope = resolve_typename_type (scope, only_current_p);
11781 /* If we don't know what SCOPE refers to, then we cannot resolve the
11783 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
11784 return error_mark_node;
11785 /* If the SCOPE is a template type parameter, we have no way of
11786 resolving the name. */
11787 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
11789 /* If the SCOPE is not the current instantiation, there's no reason
11790 to look inside it. */
11791 if (only_current_p && !currently_open_class (scope))
11792 return error_mark_node;
11793 /* If SCOPE is a partial instantiation, it will not have a valid
11794 TYPE_FIELDS list, so use the original template. */
11795 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
11796 /* Enter the SCOPE so that name lookup will be resolved as if we
11797 were in the class definition. In particular, SCOPE will no
11798 longer be considered a dependent type. */
11799 push_scope (scope);
11800 /* Look up the declaration. */
11801 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
11802 /* Obtain the set of qualifiers applied to the TYPE. */
11803 quals = cp_type_quals (type);
11804 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
11805 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
11807 type = error_mark_node;
11808 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
11809 && TREE_CODE (decl) == TYPE_DECL)
11810 type = TREE_TYPE (decl);
11811 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
11812 && DECL_CLASS_TEMPLATE_P (decl))
11816 /* Obtain the template and the arguments. */
11817 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
11818 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
11819 /* Instantiate the template. */
11820 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
11821 /*entering_scope=*/0, tf_error | tf_user);
11824 type = error_mark_node;
11825 /* Qualify the resulting type. */
11826 if (type != error_mark_node && quals)
11827 type = cp_build_qualified_type (type, quals);
11828 /* Leave the SCOPE. */
11834 /* EXPR is an expression which is not type-dependent. Return a proxy
11835 for EXPR that can be used to compute the types of larger
11836 expressions containing EXPR. */
11839 build_non_dependent_expr (tree expr)
11841 /* Preserve null pointer constants so that the type of things like
11842 "p == 0" where "p" is a pointer can be determined. */
11843 if (null_ptr_cst_p (expr))
11845 /* Preserve OVERLOADs; the functions must be available to resolve
11847 if (TREE_CODE (expr) == OVERLOAD)
11849 /* Otherwise, build a NON_DEPENDENT_EXPR.
11851 REFERENCE_TYPEs are not stripped for expressions in templates
11852 because doing so would play havoc with mangling. Consider, for
11855 template <typename T> void f<T& g>() { g(); }
11857 In the body of "f", the expression for "g" will have
11858 REFERENCE_TYPE, even though the standard says that it should
11859 not. The reason is that we must preserve the syntactic form of
11860 the expression so that mangling (say) "f<g>" inside the body of
11861 "f" works out correctly. Therefore, the REFERENCE_TYPE is
11863 return build (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)));
11866 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
11867 Return a new TREE_LIST with the various arguments replaced with
11868 equivalent non-dependent expressions. */
11871 build_non_dependent_args (tree args)
11876 new_args = NULL_TREE;
11877 for (a = args; a; a = TREE_CHAIN (a))
11878 new_args = tree_cons (NULL_TREE,
11879 build_non_dependent_expr (TREE_VALUE (a)),
11881 return nreverse (new_args);
11884 #include "gt-cp-pt.h"