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, bool);
97 static int unify (tree, tree, tree, tree, int);
98 static void add_pending_template (tree);
99 static void reopen_tinst_level (tree);
100 static tree classtype_mangled_name (tree);
101 static char* mangle_class_name_for_template (const char *, tree, tree);
102 static tree tsubst_initializer_list (tree, tree);
103 static tree get_class_bindings (tree, tree, tree);
104 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
105 static void tsubst_enum (tree, tree, tree);
106 static tree add_to_template_args (tree, tree);
107 static tree add_outermost_template_args (tree, tree);
108 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
109 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
110 static int type_unification_real (tree, tree, tree, tree,
111 int, unification_kind_t, int, int);
112 static void note_template_header (int);
113 static tree convert_nontype_argument (tree, tree);
114 static tree convert_template_argument (tree, tree, tree,
115 tsubst_flags_t, int, tree);
116 static tree get_bindings_overload (tree, tree, tree);
117 static int for_each_template_parm (tree, tree_fn_t, void*, htab_t);
118 static tree build_template_parm_index (int, int, int, tree, tree);
119 static int inline_needs_template_parms (tree);
120 static void push_inline_template_parms_recursive (tree, int);
121 static tree retrieve_specialization (tree, tree);
122 static tree retrieve_local_specialization (tree);
123 static tree register_specialization (tree, tree, tree);
124 static void register_local_specialization (tree, tree);
125 static tree reduce_template_parm_level (tree, tree, int);
126 static tree build_template_decl (tree, tree);
127 static int mark_template_parm (tree, void *);
128 static int template_parm_this_level_p (tree, void *);
129 static tree tsubst_friend_function (tree, tree);
130 static tree tsubst_friend_class (tree, tree);
131 static int can_complete_type_without_circularity (tree);
132 static tree get_bindings (tree, tree, tree);
133 static tree get_bindings_real (tree, tree, tree, int, int, int);
134 static int template_decl_level (tree);
135 static int check_cv_quals_for_unify (int, tree, tree);
136 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
137 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
138 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
139 static void regenerate_decl_from_template (tree, tree);
140 static tree most_specialized (tree, tree, tree);
141 static tree most_specialized_class (tree, tree);
142 static int template_class_depth_real (tree, int);
143 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
144 static tree tsubst_decl (tree, tree, tree, tsubst_flags_t);
145 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
146 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
147 static void check_specialization_scope (void);
148 static tree process_partial_specialization (tree);
149 static void set_current_access_from_decl (tree);
150 static void check_default_tmpl_args (tree, tree, int, int);
151 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
152 static tree get_template_base_recursive (tree, tree, tree, tree, tree, int);
153 static tree get_template_base (tree, tree, tree, tree);
154 static int verify_class_unification (tree, tree, tree);
155 static tree try_class_unification (tree, tree, tree, tree);
156 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
158 static tree determine_specialization (tree, tree, tree *, int);
159 static int template_args_equal (tree, tree);
160 static void tsubst_default_arguments (tree);
161 static tree for_each_template_parm_r (tree *, int *, void *);
162 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
163 static void copy_default_args_to_explicit_spec (tree);
164 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
165 static int eq_local_specializations (const void *, const void *);
166 static bool dependent_type_p_r (tree);
167 static tree tsubst (tree, tree, tsubst_flags_t, tree);
168 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
169 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
171 /* Make the current scope suitable for access checking when we are
172 processing T. T can be FUNCTION_DECL for instantiated function
173 template, or VAR_DECL for static member variable (need by
174 instantiate_decl). */
177 push_access_scope (tree t)
179 my_friendly_assert (TREE_CODE (t) == FUNCTION_DECL
180 || TREE_CODE (t) == VAR_DECL,
183 if (DECL_CLASS_SCOPE_P (t))
184 push_nested_class (DECL_CONTEXT (t));
186 push_to_top_level ();
188 if (TREE_CODE (t) == FUNCTION_DECL)
190 saved_access_scope = tree_cons
191 (NULL_TREE, current_function_decl, saved_access_scope);
192 current_function_decl = t;
196 /* Restore the scope set up by push_access_scope. T is the node we
200 pop_access_scope (tree t)
202 if (TREE_CODE (t) == FUNCTION_DECL)
204 current_function_decl = TREE_VALUE (saved_access_scope);
205 saved_access_scope = TREE_CHAIN (saved_access_scope);
208 if (DECL_CLASS_SCOPE_P (t))
211 pop_from_top_level ();
214 /* Do any processing required when DECL (a member template
215 declaration) is finished. Returns the TEMPLATE_DECL corresponding
216 to DECL, unless it is a specialization, in which case the DECL
217 itself is returned. */
220 finish_member_template_decl (tree decl)
222 if (decl == error_mark_node)
223 return error_mark_node;
225 my_friendly_assert (DECL_P (decl), 20020812);
227 if (TREE_CODE (decl) == TYPE_DECL)
231 type = TREE_TYPE (decl);
232 if (IS_AGGR_TYPE (type)
233 && CLASSTYPE_TEMPLATE_INFO (type)
234 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
236 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
237 check_member_template (tmpl);
242 else if (TREE_CODE (decl) == FIELD_DECL)
243 error ("data member `%D' cannot be a member template", decl);
244 else if (DECL_TEMPLATE_INFO (decl))
246 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
248 check_member_template (DECL_TI_TEMPLATE (decl));
249 return DECL_TI_TEMPLATE (decl);
255 error ("invalid member template declaration `%D'", decl);
257 return error_mark_node;
260 /* Returns the template nesting level of the indicated class TYPE.
270 A<T>::B<U> has depth two, while A<T> has depth one.
271 Both A<T>::B<int> and A<int>::B<U> have depth one, if
272 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
275 This function is guaranteed to return 0 if passed NULL_TREE so
276 that, for example, `template_class_depth (current_class_type)' is
280 template_class_depth_real (tree type, int count_specializations)
285 type && TREE_CODE (type) != NAMESPACE_DECL;
286 type = (TREE_CODE (type) == FUNCTION_DECL)
287 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
289 if (TREE_CODE (type) != FUNCTION_DECL)
291 if (CLASSTYPE_TEMPLATE_INFO (type)
292 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
293 && ((count_specializations
294 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
295 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
300 if (DECL_TEMPLATE_INFO (type)
301 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
302 && ((count_specializations
303 && DECL_TEMPLATE_SPECIALIZATION (type))
304 || uses_template_parms (DECL_TI_ARGS (type))))
312 /* Returns the template nesting level of the indicated class TYPE.
313 Like template_class_depth_real, but instantiations do not count in
317 template_class_depth (tree type)
319 return template_class_depth_real (type, /*count_specializations=*/0);
322 /* Returns 1 if processing DECL as part of do_pending_inlines
323 needs us to push template parms. */
326 inline_needs_template_parms (tree decl)
328 if (! DECL_TEMPLATE_INFO (decl))
331 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
332 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
335 /* Subroutine of maybe_begin_member_template_processing.
336 Push the template parms in PARMS, starting from LEVELS steps into the
337 chain, and ending at the beginning, since template parms are listed
341 push_inline_template_parms_recursive (tree parmlist, int levels)
343 tree parms = TREE_VALUE (parmlist);
347 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
349 ++processing_template_decl;
350 current_template_parms
351 = tree_cons (size_int (processing_template_decl),
352 parms, current_template_parms);
353 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
355 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
357 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
359 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
360 my_friendly_assert (DECL_P (parm), 0);
362 switch (TREE_CODE (parm))
371 /* Make a CONST_DECL as is done in process_template_parm.
372 It is ugly that we recreate this here; the original
373 version built in process_template_parm is no longer
375 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
377 DECL_ARTIFICIAL (decl) = 1;
378 TREE_CONSTANT (decl) = TREE_READONLY (decl) = 1;
379 DECL_INITIAL (decl) = DECL_INITIAL (parm);
380 SET_DECL_TEMPLATE_PARM_P (decl);
391 /* Restore the template parameter context for a member template or
392 a friend template defined in a class definition. */
395 maybe_begin_member_template_processing (tree decl)
400 if (inline_needs_template_parms (decl))
402 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
403 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
405 if (DECL_TEMPLATE_SPECIALIZATION (decl))
408 parms = TREE_CHAIN (parms);
411 push_inline_template_parms_recursive (parms, levels);
414 /* Remember how many levels of template parameters we pushed so that
415 we can pop them later. */
416 if (!inline_parm_levels)
417 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
418 if (inline_parm_levels_used == inline_parm_levels->num_elements)
419 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
420 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
421 ++inline_parm_levels_used;
424 /* Undo the effects of begin_member_template_processing. */
427 maybe_end_member_template_processing (void)
431 if (!inline_parm_levels_used)
434 --inline_parm_levels_used;
436 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
439 --processing_template_decl;
440 current_template_parms = TREE_CHAIN (current_template_parms);
445 /* Returns nonzero iff T is a member template function. We must be
448 template <class T> class C { void f(); }
450 Here, f is a template function, and a member, but not a member
451 template. This function does not concern itself with the origin of
452 T, only its present state. So if we have
454 template <class T> class C { template <class U> void f(U); }
456 then neither C<int>::f<char> nor C<T>::f<double> is considered
457 to be a member template. But, `template <class U> void
458 C<int>::f(U)' is considered a member template. */
461 is_member_template (tree t)
463 if (!DECL_FUNCTION_TEMPLATE_P (t))
464 /* Anything that isn't a function or a template function is
465 certainly not a member template. */
468 /* A local class can't have member templates. */
469 if (decl_function_context (t))
472 return (DECL_FUNCTION_MEMBER_P (DECL_TEMPLATE_RESULT (t))
473 /* If there are more levels of template parameters than
474 there are template classes surrounding the declaration,
475 then we have a member template. */
476 && (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
477 template_class_depth (DECL_CONTEXT (t))));
481 /* Returns nonzero iff T is a member template class. See
482 is_member_template for a description of what precisely constitutes
483 a member template. */
486 is_member_template_class (tree t)
488 if (!DECL_CLASS_TEMPLATE_P (t))
489 /* Anything that isn't a class template, is certainly not a member
493 if (!DECL_CLASS_SCOPE_P (t))
494 /* Anything whose context isn't a class type is surely not a
498 /* If there are more levels of template parameters than there are
499 template classes surrounding the declaration, then we have a
501 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
502 template_class_depth (DECL_CONTEXT (t)));
506 /* Return a new template argument vector which contains all of ARGS,
507 but has as its innermost set of arguments the EXTRA_ARGS. */
510 add_to_template_args (tree args, tree extra_args)
517 extra_depth = TMPL_ARGS_DEPTH (extra_args);
518 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
520 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
521 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
523 for (j = 1; j <= extra_depth; ++j, ++i)
524 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
529 /* Like add_to_template_args, but only the outermost ARGS are added to
530 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
531 (EXTRA_ARGS) levels are added. This function is used to combine
532 the template arguments from a partial instantiation with the
533 template arguments used to attain the full instantiation from the
534 partial instantiation. */
537 add_outermost_template_args (tree args, tree extra_args)
541 /* If there are more levels of EXTRA_ARGS than there are ARGS,
542 something very fishy is going on. */
543 my_friendly_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args),
546 /* If *all* the new arguments will be the EXTRA_ARGS, just return
548 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
551 /* For the moment, we make ARGS look like it contains fewer levels. */
552 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
554 new_args = add_to_template_args (args, extra_args);
556 /* Now, we restore ARGS to its full dimensions. */
557 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
562 /* Return the N levels of innermost template arguments from the ARGS. */
565 get_innermost_template_args (tree args, int n)
571 my_friendly_assert (n >= 0, 20000603);
573 /* If N is 1, just return the innermost set of template arguments. */
575 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
577 /* If we're not removing anything, just return the arguments we were
579 extra_levels = TMPL_ARGS_DEPTH (args) - n;
580 my_friendly_assert (extra_levels >= 0, 20000603);
581 if (extra_levels == 0)
584 /* Make a new set of arguments, not containing the outer arguments. */
585 new_args = make_tree_vec (n);
586 for (i = 1; i <= n; ++i)
587 SET_TMPL_ARGS_LEVEL (new_args, i,
588 TMPL_ARGS_LEVEL (args, i + extra_levels));
593 /* We've got a template header coming up; push to a new level for storing
597 begin_template_parm_list (void)
599 /* We use a non-tag-transparent scope here, which causes pushtag to
600 put tags in this scope, rather than in the enclosing class or
601 namespace scope. This is the right thing, since we want
602 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
603 global template class, push_template_decl handles putting the
604 TEMPLATE_DECL into top-level scope. For a nested template class,
607 template <class T> struct S1 {
608 template <class T> struct S2 {};
611 pushtag contains special code to call pushdecl_with_scope on the
612 TEMPLATE_DECL for S2. */
613 begin_scope (sk_template_parms, NULL);
614 ++processing_template_decl;
615 ++processing_template_parmlist;
616 note_template_header (0);
619 /* This routine is called when a specialization is declared. If it is
620 invalid to declare a specialization here, an error is reported. */
623 check_specialization_scope (void)
625 tree scope = current_scope ();
629 An explicit specialization shall be declared in the namespace of
630 which the template is a member, or, for member templates, in the
631 namespace of which the enclosing class or enclosing class
632 template is a member. An explicit specialization of a member
633 function, member class or static data member of a class template
634 shall be declared in the namespace of which the class template
636 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
637 error ("explicit specialization in non-namespace scope `%D'",
642 In an explicit specialization declaration for a member of a class
643 template or a member template that appears in namespace scope,
644 the member template and some of its enclosing class templates may
645 remain unspecialized, except that the declaration shall not
646 explicitly specialize a class member template if its enclosing
647 class templates are not explicitly specialized as well. */
648 if (current_template_parms)
649 error ("enclosing class templates are not explicitly specialized");
652 /* We've just seen template <>. */
655 begin_specialization (void)
657 begin_scope (sk_template_spec, NULL);
658 note_template_header (1);
659 check_specialization_scope ();
662 /* Called at then end of processing a declaration preceded by
666 end_specialization (void)
669 reset_specialization ();
672 /* Any template <>'s that we have seen thus far are not referring to a
673 function specialization. */
676 reset_specialization (void)
678 processing_specialization = 0;
679 template_header_count = 0;
682 /* We've just seen a template header. If SPECIALIZATION is nonzero,
683 it was of the form template <>. */
686 note_template_header (int specialization)
688 processing_specialization = specialization;
689 template_header_count++;
692 /* We're beginning an explicit instantiation. */
695 begin_explicit_instantiation (void)
697 my_friendly_assert (!processing_explicit_instantiation, 20020913);
698 processing_explicit_instantiation = true;
703 end_explicit_instantiation (void)
705 my_friendly_assert(processing_explicit_instantiation, 20020913);
706 processing_explicit_instantiation = false;
709 /* The TYPE is being declared. If it is a template type, that means it
710 is a partial specialization. Do appropriate error-checking. */
713 maybe_process_partial_specialization (tree type)
715 /* TYPE maybe an ERROR_MARK_NODE. */
716 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
718 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
720 /* This is for ordinary explicit specialization and partial
721 specialization of a template class such as:
723 template <> class C<int>;
727 template <class T> class C<T*>;
729 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
731 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
732 && !COMPLETE_TYPE_P (type))
734 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_method_type_directly (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 (TREE_CODE (decl) == FUNCTION_DECL
2679 && DECL_DESTRUCTOR_P (decl))
2683 A destructor shall not be a member template. */
2684 error ("destructor `%D' declared as member template", decl);
2685 return error_mark_node;
2687 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2688 && CLASS_TYPE_P (TREE_TYPE (decl)))
2689 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx))
2690 || TREE_CODE (decl) == FUNCTION_DECL)
2693 error ("template declaration of `%#D'", decl);
2696 /* Check to see that the rules regarding the use of default
2697 arguments are not being violated. */
2698 check_default_tmpl_args (decl, current_template_parms,
2699 primary, is_partial);
2702 return process_partial_specialization (decl);
2704 args = current_template_args ();
2707 || TREE_CODE (ctx) == FUNCTION_DECL
2708 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
2709 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
2711 if (DECL_LANG_SPECIFIC (decl)
2712 && DECL_TEMPLATE_INFO (decl)
2713 && DECL_TI_TEMPLATE (decl))
2714 tmpl = DECL_TI_TEMPLATE (decl);
2715 /* If DECL is a TYPE_DECL for a class-template, then there won't
2716 be DECL_LANG_SPECIFIC. The information equivalent to
2717 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2718 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
2719 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2720 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2722 /* Since a template declaration already existed for this
2723 class-type, we must be redeclaring it here. Make sure
2724 that the redeclaration is valid. */
2725 redeclare_class_template (TREE_TYPE (decl),
2726 current_template_parms);
2727 /* We don't need to create a new TEMPLATE_DECL; just use the
2728 one we already had. */
2729 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2733 tmpl = build_template_decl (decl, current_template_parms);
2736 if (DECL_LANG_SPECIFIC (decl)
2737 && DECL_TEMPLATE_SPECIALIZATION (decl))
2739 /* A specialization of a member template of a template
2741 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2742 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
2743 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
2749 tree a, t, current, parms;
2752 if (TREE_CODE (decl) == TYPE_DECL)
2754 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
2755 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
2756 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2757 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2758 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2761 error ("`%D' does not declare a template type", decl);
2765 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
2767 error ("template definition of non-template `%#D'", decl);
2771 tmpl = DECL_TI_TEMPLATE (decl);
2773 if (is_member_template (tmpl)
2774 && DECL_FUNCTION_TEMPLATE_P (tmpl)
2775 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
2776 && DECL_TEMPLATE_SPECIALIZATION (decl))
2780 /* The declaration is a specialization of a member
2781 template, declared outside the class. Therefore, the
2782 innermost template arguments will be NULL, so we
2783 replace them with the arguments determined by the
2784 earlier call to check_explicit_specialization. */
2785 args = DECL_TI_ARGS (decl);
2788 = build_template_decl (decl, current_template_parms);
2789 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
2790 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
2791 DECL_TI_TEMPLATE (decl) = new_tmpl;
2792 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
2793 DECL_TEMPLATE_INFO (new_tmpl)
2794 = tree_cons (tmpl, args, NULL_TREE);
2796 register_specialization (new_tmpl,
2797 most_general_template (tmpl),
2802 /* Make sure the template headers we got make sense. */
2804 parms = DECL_TEMPLATE_PARMS (tmpl);
2805 i = TMPL_PARMS_DEPTH (parms);
2806 if (TMPL_ARGS_DEPTH (args) != i)
2808 error ("expected %d levels of template parms for `%#D', got %d",
2809 i, decl, TMPL_ARGS_DEPTH (args));
2812 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
2814 a = TMPL_ARGS_LEVEL (args, i);
2815 t = INNERMOST_TEMPLATE_PARMS (parms);
2817 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
2819 if (current == decl)
2820 error ("got %d template parameters for `%#D'",
2821 TREE_VEC_LENGTH (a), decl);
2823 error ("got %d template parameters for `%#T'",
2824 TREE_VEC_LENGTH (a), current);
2825 error (" but %d required", TREE_VEC_LENGTH (t));
2828 /* Perhaps we should also check that the parms are used in the
2829 appropriate qualifying scopes in the declarator? */
2831 if (current == decl)
2834 current = TYPE_CONTEXT (current);
2838 DECL_TEMPLATE_RESULT (tmpl) = decl;
2839 TREE_TYPE (tmpl) = TREE_TYPE (decl);
2841 /* Push template declarations for global functions and types. Note
2842 that we do not try to push a global template friend declared in a
2843 template class; such a thing may well depend on the template
2844 parameters of the class. */
2845 if (new_template_p && !ctx
2846 && !(is_friend && template_class_depth (current_class_type) > 0))
2847 tmpl = pushdecl_namespace_level (tmpl);
2851 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
2852 if (DECL_CONV_FN_P (tmpl))
2854 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2856 /* It is a conversion operator. See if the type converted to
2857 depends on innermost template operands. */
2859 if (for_each_template_parm (TREE_TYPE (TREE_TYPE (tmpl)),
2860 template_parm_this_level_p,
2863 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
2867 info = tree_cons (tmpl, args, NULL_TREE);
2869 if (DECL_IMPLICIT_TYPEDEF_P (decl))
2871 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
2872 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
2873 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2874 /* Don't change the name if we've already set it up. */
2875 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
2876 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
2878 else if (DECL_LANG_SPECIFIC (decl))
2879 DECL_TEMPLATE_INFO (decl) = info;
2881 return DECL_TEMPLATE_RESULT (tmpl);
2885 push_template_decl (tree decl)
2887 return push_template_decl_real (decl, 0);
2890 /* Called when a class template TYPE is redeclared with the indicated
2891 template PARMS, e.g.:
2893 template <class T> struct S;
2894 template <class T> struct S {}; */
2897 redeclare_class_template (tree type, tree parms)
2903 if (!TYPE_TEMPLATE_INFO (type))
2905 error ("`%T' is not a template type", type);
2909 tmpl = TYPE_TI_TEMPLATE (type);
2910 if (!PRIMARY_TEMPLATE_P (tmpl))
2911 /* The type is nested in some template class. Nothing to worry
2912 about here; there are no new template parameters for the nested
2916 parms = INNERMOST_TEMPLATE_PARMS (parms);
2917 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
2919 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
2921 cp_error_at ("previous declaration `%D'", tmpl);
2922 error ("used %d template parameter%s instead of %d",
2923 TREE_VEC_LENGTH (tmpl_parms),
2924 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
2925 TREE_VEC_LENGTH (parms));
2929 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
2931 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
2932 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
2933 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
2934 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
2936 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm))
2938 cp_error_at ("template parameter `%#D'", tmpl_parm);
2939 error ("redeclared here as `%#D'", parm);
2943 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
2945 /* We have in [temp.param]:
2947 A template-parameter may not be given default arguments
2948 by two different declarations in the same scope. */
2949 error ("redefinition of default argument for `%#D'", parm);
2950 error ("%J original definition appeared here", tmpl_parm);
2954 if (parm_default != NULL_TREE)
2955 /* Update the previous template parameters (which are the ones
2956 that will really count) with the new default value. */
2957 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
2958 else if (tmpl_default != NULL_TREE)
2959 /* Update the new parameters, too; they'll be used as the
2960 parameters for any members. */
2961 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
2965 /* Attempt to convert the non-type template parameter EXPR to the
2966 indicated TYPE. If the conversion is successful, return the
2967 converted value. If the conversion is unsuccessful, return
2968 NULL_TREE if we issued an error message, or error_mark_node if we
2969 did not. We issue error messages for out-and-out bad template
2970 parameters, but not simply because the conversion failed, since we
2971 might be just trying to do argument deduction. By the time this
2972 function is called, neither TYPE nor EXPR may make use of template
2976 convert_nontype_argument (tree type, tree expr)
2978 tree expr_type = TREE_TYPE (expr);
2980 /* A template-argument for a non-type, non-template
2981 template-parameter shall be one of:
2983 --an integral constant-expression of integral or enumeration
2986 --the name of a non-type template-parameter; or
2988 --the name of an object or function with external linkage,
2989 including function templates and function template-ids but
2990 excluding non-static class members, expressed as id-expression;
2993 --the address of an object or function with external linkage,
2994 including function templates and function template-ids but
2995 excluding non-static class members, expressed as & id-expression
2996 where the & is optional if the name refers to a function or
2999 --a pointer to member expressed as described in _expr.unary.op_. */
3001 /* An integral constant-expression can include const variables or
3002 enumerators. Simplify things by folding them to their values,
3003 unless we're about to bind the declaration to a reference
3005 if (INTEGRAL_TYPE_P (expr_type)
3006 && TREE_CODE (type) != REFERENCE_TYPE)
3007 expr = decl_constant_value (expr);
3009 if (is_overloaded_fn (expr))
3010 /* OK for now. We'll check that it has external linkage later.
3011 Check this first since if expr_type is the unknown_type_node
3012 we would otherwise complain below. */
3014 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3016 if (TREE_CODE (expr) != PTRMEM_CST)
3019 else if (TYPE_PTR_P (expr_type)
3020 || TREE_CODE (expr_type) == ARRAY_TYPE
3021 || TREE_CODE (type) == REFERENCE_TYPE
3022 /* If expr is the address of an overloaded function, we
3023 will get the unknown_type_node at this point. */
3024 || expr_type == unknown_type_node)
3030 if (TREE_CODE (expr_type) == ARRAY_TYPE
3031 || (TREE_CODE (type) == REFERENCE_TYPE
3032 && TREE_CODE (e) != ADDR_EXPR))
3036 if (TREE_CODE (e) != ADDR_EXPR)
3039 error ("`%E' is not a valid template argument", expr);
3040 if (TYPE_PTR_P (expr_type))
3042 if (TREE_CODE (TREE_TYPE (expr_type)) == FUNCTION_TYPE)
3043 error ("it must be the address of a function with external linkage");
3045 error ("it must be the address of an object with external linkage");
3047 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3048 error ("it must be a pointer-to-member of the form `&X::Y'");
3053 referent = TREE_OPERAND (e, 0);
3054 STRIP_NOPS (referent);
3057 if (TREE_CODE (referent) == STRING_CST)
3059 error ("string literal %E is not a valid template argument because it is the address of an object with static linkage",
3064 if (TREE_CODE (referent) == SCOPE_REF)
3065 referent = TREE_OPERAND (referent, 1);
3067 if (is_overloaded_fn (referent))
3068 /* We'll check that it has external linkage later. */
3070 else if (TREE_CODE (referent) != VAR_DECL)
3072 else if (!DECL_EXTERNAL_LINKAGE_P (referent))
3074 error ("address of non-extern `%E' cannot be used as template argument", referent);
3075 return error_mark_node;
3078 else if (INTEGRAL_TYPE_P (expr_type) || TYPE_PTR_TO_MEMBER_P (expr_type))
3080 if (! TREE_CONSTANT (expr))
3083 error ("non-constant `%E' cannot be used as template argument",
3091 error ("type '%T' cannot be used as a value for a non-type "
3092 "template-parameter", expr);
3093 else if (DECL_P (expr))
3094 error ("invalid use of '%D' as a non-type template-argument", expr);
3096 error ("invalid use of '%E' as a non-type template-argument", expr);
3101 switch (TREE_CODE (type))
3106 /* For a non-type template-parameter of integral or enumeration
3107 type, integral promotions (_conv.prom_) and integral
3108 conversions (_conv.integral_) are applied. */
3109 if (!INTEGRAL_TYPE_P (expr_type))
3110 return error_mark_node;
3112 /* It's safe to call digest_init in this case; we know we're
3113 just converting one integral constant expression to another. */
3114 expr = digest_init (type, expr, (tree*) 0);
3116 if (TREE_CODE (expr) != INTEGER_CST)
3117 /* Curiously, some TREE_CONSTANT integral expressions do not
3118 simplify to integer constants. For example, `3 % 0',
3119 remains a TRUNC_MOD_EXPR. */
3128 /* For a non-type template-parameter of type pointer to data
3129 member, qualification conversions (_conv.qual_) are
3131 e = perform_qualification_conversions (type, expr);
3132 if (TREE_CODE (e) == NOP_EXPR)
3133 /* The call to perform_qualification_conversions will
3134 insert a NOP_EXPR over EXPR to do express conversion,
3135 if necessary. But, that will confuse us if we use
3136 this (converted) template parameter to instantiate
3137 another template; then the thing will not look like a
3138 valid template argument. So, just make a new
3139 constant, of the appropriate type. */
3140 e = make_ptrmem_cst (type, PTRMEM_CST_MEMBER (expr));
3146 tree type_pointed_to = TREE_TYPE (type);
3148 if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE)
3150 /* For a non-type template-parameter of type pointer to
3151 function, only the function-to-pointer conversion
3152 (_conv.func_) is applied. If the template-argument
3153 represents a set of overloaded functions (or a pointer to
3154 such), the matching function is selected from the set
3159 if (TREE_CODE (expr) == ADDR_EXPR)
3160 fns = TREE_OPERAND (expr, 0);
3164 fn = instantiate_type (type_pointed_to, fns, tf_none);
3166 if (fn == error_mark_node)
3167 return error_mark_node;
3169 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3171 if (really_overloaded_fn (fns))
3172 return error_mark_node;
3177 expr = build_unary_op (ADDR_EXPR, fn, 0);
3179 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3185 /* For a non-type template-parameter of type pointer to
3186 object, qualification conversions (_conv.qual_) and the
3187 array-to-pointer conversion (_conv.array_) are applied.
3188 [Note: In particular, neither the null pointer conversion
3189 (_conv.ptr_) nor the derived-to-base conversion
3190 (_conv.ptr_) are applied. Although 0 is a valid
3191 template-argument for a non-type template-parameter of
3192 integral type, it is not a valid template-argument for a
3193 non-type template-parameter of pointer type.]
3195 The call to decay_conversion performs the
3196 array-to-pointer conversion, if appropriate. */
3197 expr = decay_conversion (expr);
3199 if (expr == error_mark_node)
3200 return error_mark_node;
3202 return perform_qualification_conversions (type, expr);
3207 case REFERENCE_TYPE:
3209 tree type_referred_to = TREE_TYPE (type);
3211 /* If this expression already has reference type, get the
3212 underlying object. */
3213 if (TREE_CODE (expr_type) == REFERENCE_TYPE)
3215 if (TREE_CODE (expr) == NOP_EXPR
3216 && TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR)
3218 my_friendly_assert (TREE_CODE (expr) == ADDR_EXPR, 20000604);
3219 expr = TREE_OPERAND (expr, 0);
3220 expr_type = TREE_TYPE (expr);
3223 if (TREE_CODE (type_referred_to) == FUNCTION_TYPE)
3225 /* For a non-type template-parameter of type reference to
3226 function, no conversions apply. If the
3227 template-argument represents a set of overloaded
3228 functions, the matching function is selected from the
3229 set (_over.over_). */
3232 fn = instantiate_type (type_referred_to, expr, tf_none);
3234 if (fn == error_mark_node)
3235 return error_mark_node;
3237 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3239 if (really_overloaded_fn (expr))
3240 /* Don't issue an error here; we might get a different
3241 function if the overloading had worked out
3243 return error_mark_node;
3248 my_friendly_assert (same_type_p (type_referred_to,
3256 /* For a non-type template-parameter of type reference to
3257 object, no conversions apply. The type referred to by the
3258 reference may be more cv-qualified than the (otherwise
3259 identical) type of the template-argument. The
3260 template-parameter is bound directly to the
3261 template-argument, which must be an lvalue. */
3262 if (!same_type_p (TYPE_MAIN_VARIANT (expr_type),
3263 TYPE_MAIN_VARIANT (type_referred_to))
3264 || !at_least_as_qualified_p (type_referred_to,
3266 || !real_lvalue_p (expr))
3267 return error_mark_node;
3270 cxx_mark_addressable (expr);
3271 return build_nop (type, build_address (expr));
3277 my_friendly_assert (TYPE_PTRMEMFUNC_P (type), 20010112);
3279 /* For a non-type template-parameter of type pointer to member
3280 function, no conversions apply. If the template-argument
3281 represents a set of overloaded member functions, the
3282 matching member function is selected from the set
3285 if (!TYPE_PTRMEMFUNC_P (expr_type) &&
3286 expr_type != unknown_type_node)
3287 return error_mark_node;
3289 if (TREE_CODE (expr) == PTRMEM_CST)
3291 /* A ptr-to-member constant. */
3292 if (!same_type_p (type, expr_type))
3293 return error_mark_node;
3298 if (TREE_CODE (expr) != ADDR_EXPR)
3299 return error_mark_node;
3301 expr = instantiate_type (type, expr, tf_none);
3303 if (expr == error_mark_node)
3304 return error_mark_node;
3306 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3313 /* All non-type parameters must have one of these types. */
3318 return error_mark_node;
3321 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3322 template template parameters. Both PARM_PARMS and ARG_PARMS are
3323 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3326 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3327 the case, then extra parameters must have default arguments.
3329 Consider the example:
3330 template <class T, class Allocator = allocator> class vector;
3331 template<template <class U> class TT> class C;
3333 C<vector> is a valid instantiation. PARM_PARMS for the above code
3334 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3335 T and Allocator) and OUTER_ARGS contains the argument that is used to
3336 substitute the TT parameter. */
3339 coerce_template_template_parms (tree parm_parms,
3341 tsubst_flags_t complain,
3345 int nparms, nargs, i;
3348 my_friendly_assert (TREE_CODE (parm_parms) == TREE_VEC, 0);
3349 my_friendly_assert (TREE_CODE (arg_parms) == TREE_VEC, 0);
3351 nparms = TREE_VEC_LENGTH (parm_parms);
3352 nargs = TREE_VEC_LENGTH (arg_parms);
3354 /* The rule here is opposite of coerce_template_parms. */
3357 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3360 for (i = 0; i < nparms; ++i)
3362 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3363 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3365 if (arg == NULL_TREE || arg == error_mark_node
3366 || parm == NULL_TREE || parm == error_mark_node)
3369 if (TREE_CODE (arg) != TREE_CODE (parm))
3372 switch (TREE_CODE (parm))
3378 /* We encounter instantiations of templates like
3379 template <template <template <class> class> class TT>
3382 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3383 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3385 if (!coerce_template_template_parms
3386 (parmparm, argparm, complain, in_decl, outer_args))
3392 /* The tsubst call is used to handle cases such as
3393 template <class T, template <T> class TT> class D;
3394 i.e. the parameter list of TT depends on earlier parameters. */
3396 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3408 /* Convert the indicated template ARG as necessary to match the
3409 indicated template PARM. Returns the converted ARG, or
3410 error_mark_node if the conversion was unsuccessful. Error and
3411 warning messages are issued under control of COMPLAIN. This
3412 conversion is for the Ith parameter in the parameter list. ARGS is
3413 the full set of template arguments deduced so far. */
3416 convert_template_argument (tree parm,
3419 tsubst_flags_t complain,
3425 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3427 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3429 if (TREE_CODE (arg) == TREE_LIST
3430 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3432 /* The template argument was the name of some
3433 member function. That's usually
3434 invalid, but static members are OK. In any
3435 case, grab the underlying fields/functions
3436 and issue an error later if required. */
3437 arg = TREE_VALUE (arg);
3438 TREE_TYPE (arg) = unknown_type_node;
3441 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3442 requires_type = (TREE_CODE (parm) == TYPE_DECL
3443 || requires_tmpl_type);
3445 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3446 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3447 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3448 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3451 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3452 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3453 arg = TYPE_STUB_DECL (arg);
3455 is_type = TYPE_P (arg) || is_tmpl_type;
3457 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3458 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3460 pedwarn ("to refer to a type member of a template parameter, use `typename %E'", arg);
3462 arg = make_typename_type (TREE_OPERAND (arg, 0),
3463 TREE_OPERAND (arg, 1),
3464 complain & tf_error);
3467 if (is_type != requires_type)
3471 if (complain & tf_error)
3473 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3476 error (" expected a constant of type `%T', got `%T'",
3478 (is_tmpl_type ? DECL_NAME (arg) : arg));
3479 else if (requires_tmpl_type)
3480 error (" expected a class template, got `%E'", arg);
3482 error (" expected a type, got `%E'", arg);
3485 return error_mark_node;
3487 if (is_tmpl_type ^ requires_tmpl_type)
3489 if (in_decl && (complain & tf_error))
3491 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3494 error (" expected a type, got `%T'", DECL_NAME (arg));
3496 error (" expected a class template, got `%T'", arg);
3498 return error_mark_node;
3503 if (requires_tmpl_type)
3505 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3506 /* The number of argument required is not known yet.
3507 Just accept it for now. */
3508 val = TREE_TYPE (arg);
3511 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3512 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3514 if (coerce_template_template_parms (parmparm, argparm,
3520 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3522 if (val != error_mark_node
3523 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3524 val = TREE_TYPE (val);
3528 if (in_decl && (complain & tf_error))
3530 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3532 error (" expected a template of type `%D', got `%D'", parm, arg);
3535 val = error_mark_node;
3540 val = groktypename (arg);
3544 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3546 if (invalid_nontype_parm_type_p (t, complain))
3547 return error_mark_node;
3549 if (!uses_template_parms (arg) && !uses_template_parms (t))
3550 /* We used to call digest_init here. However, digest_init
3551 will report errors, which we don't want when complain
3552 is zero. More importantly, digest_init will try too
3553 hard to convert things: for example, `0' should not be
3554 converted to pointer type at this point according to
3555 the standard. Accepting this is not merely an
3556 extension, since deciding whether or not these
3557 conversions can occur is part of determining which
3558 function template to call, or whether a given explicit
3559 argument specification is valid. */
3560 val = convert_nontype_argument (t, arg);
3564 if (val == NULL_TREE)
3565 val = error_mark_node;
3566 else if (val == error_mark_node && (complain & tf_error))
3567 error ("could not convert template argument `%E' to `%T'",
3574 /* Convert all template arguments to their appropriate types, and
3575 return a vector containing the innermost resulting template
3576 arguments. If any error occurs, return error_mark_node. Error and
3577 warning messages are issued under control of COMPLAIN.
3579 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3580 provided in ARGLIST, or else trailing parameters must have default
3581 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3582 deduction for any unspecified trailing arguments. */
3585 coerce_template_parms (tree parms,
3588 tsubst_flags_t complain,
3589 int require_all_arguments)
3591 int nparms, nargs, i, lost = 0;
3594 tree new_inner_args;
3596 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3597 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3598 nparms = TREE_VEC_LENGTH (parms);
3602 && require_all_arguments
3603 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3605 if (complain & tf_error)
3607 error ("wrong number of template arguments (%d, should be %d)",
3611 cp_error_at ("provided for `%D'", in_decl);
3614 return error_mark_node;
3617 new_inner_args = make_tree_vec (nparms);
3618 new_args = add_outermost_template_args (args, new_inner_args);
3619 for (i = 0; i < nparms; i++)
3624 /* Get the Ith template parameter. */
3625 parm = TREE_VEC_ELT (parms, i);
3627 /* Calculate the Ith argument. */
3629 arg = TREE_VEC_ELT (inner_args, i);
3630 else if (require_all_arguments)
3631 /* There must be a default arg in this case. */
3632 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
3637 my_friendly_assert (arg, 20030727);
3638 if (arg == error_mark_node)
3639 error ("template argument %d is invalid", i + 1);
3641 arg = convert_template_argument (TREE_VALUE (parm),
3642 arg, new_args, complain, i,
3645 if (arg == error_mark_node)
3647 TREE_VEC_ELT (new_inner_args, i) = arg;
3651 return error_mark_node;
3653 return new_inner_args;
3656 /* Returns 1 if template args OT and NT are equivalent. */
3659 template_args_equal (tree ot, tree nt)
3664 if (TREE_CODE (nt) == TREE_VEC)
3665 /* For member templates */
3666 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
3667 else if (TYPE_P (nt))
3668 return TYPE_P (ot) && same_type_p (ot, nt);
3669 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
3672 return cp_tree_equal (ot, nt);
3675 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
3676 of template arguments. Returns 0 otherwise. */
3679 comp_template_args (tree oldargs, tree newargs)
3683 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
3686 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
3688 tree nt = TREE_VEC_ELT (newargs, i);
3689 tree ot = TREE_VEC_ELT (oldargs, i);
3691 if (! template_args_equal (ot, nt))
3697 /* Given class template name and parameter list, produce a user-friendly name
3698 for the instantiation. */
3701 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
3703 static struct obstack scratch_obstack;
3704 static char *scratch_firstobj;
3707 if (!scratch_firstobj)
3708 gcc_obstack_init (&scratch_obstack);
3710 obstack_free (&scratch_obstack, scratch_firstobj);
3711 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
3713 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
3714 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
3718 nparms = TREE_VEC_LENGTH (parms);
3719 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
3720 my_friendly_assert (nparms == TREE_VEC_LENGTH (arglist), 268);
3721 for (i = 0; i < nparms; i++)
3723 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3724 tree arg = TREE_VEC_ELT (arglist, i);
3729 if (TREE_CODE (parm) == TYPE_DECL)
3731 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
3734 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3736 if (TREE_CODE (arg) == TEMPLATE_DECL)
3738 /* Already substituted with real template. Just output
3739 the template name here */
3740 tree context = DECL_CONTEXT (arg);
3743 /* The template may be defined in a namespace, or
3744 may be a member template. */
3745 my_friendly_assert (TREE_CODE (context) == NAMESPACE_DECL
3746 || CLASS_TYPE_P (context),
3748 cat(decl_as_string (DECL_CONTEXT (arg), TFF_PLAIN_IDENTIFIER));
3751 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
3754 /* Output the parameter declaration */
3755 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
3759 my_friendly_assert (TREE_CODE (parm) == PARM_DECL, 269);
3761 /* No need to check arglist against parmlist here; we did that
3762 in coerce_template_parms, called from lookup_template_class. */
3763 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
3766 char *bufp = obstack_next_free (&scratch_obstack);
3768 while (bufp[offset - 1] == ' ')
3770 obstack_blank_fast (&scratch_obstack, offset);
3772 /* B<C<char> >, not B<C<char>> */
3773 if (bufp[offset - 1] == '>')
3778 return (char *) obstack_base (&scratch_obstack);
3782 classtype_mangled_name (tree t)
3784 if (CLASSTYPE_TEMPLATE_INFO (t)
3785 /* Specializations have already had their names set up in
3786 lookup_template_class. */
3787 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
3789 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
3791 /* For non-primary templates, the template parameters are
3792 implicit from their surrounding context. */
3793 if (PRIMARY_TEMPLATE_P (tmpl))
3795 tree name = DECL_NAME (tmpl);
3796 char *mangled_name = mangle_class_name_for_template
3797 (IDENTIFIER_POINTER (name),
3798 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
3799 CLASSTYPE_TI_ARGS (t));
3800 tree id = get_identifier (mangled_name);
3801 IDENTIFIER_TEMPLATE (id) = name;
3806 return TYPE_IDENTIFIER (t);
3810 add_pending_template (tree d)
3812 tree ti = (TYPE_P (d)
3813 ? CLASSTYPE_TEMPLATE_INFO (d)
3814 : DECL_TEMPLATE_INFO (d));
3818 if (TI_PENDING_TEMPLATE_FLAG (ti))
3821 /* We are called both from instantiate_decl, where we've already had a
3822 tinst_level pushed, and instantiate_template, where we haven't.
3824 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
3827 push_tinst_level (d);
3829 pt = tree_cons (current_tinst_level, d, NULL_TREE);
3830 if (last_pending_template)
3831 TREE_CHAIN (last_pending_template) = pt;
3833 pending_templates = pt;
3835 last_pending_template = pt;
3837 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
3844 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
3845 ARGLIST. Valid choices for FNS are given in the cp-tree.def
3846 documentation for TEMPLATE_ID_EXPR. */
3849 lookup_template_function (tree fns, tree arglist)
3853 if (fns == error_mark_node || arglist == error_mark_node)
3854 return error_mark_node;
3856 my_friendly_assert (!arglist || TREE_CODE (arglist) == TREE_VEC, 20030726);
3857 if (fns == NULL_TREE
3858 || TREE_CODE (fns) == FUNCTION_DECL)
3860 error ("non-template used as template");
3861 return error_mark_node;
3864 my_friendly_assert (TREE_CODE (fns) == TEMPLATE_DECL
3865 || TREE_CODE (fns) == OVERLOAD
3867 || TREE_CODE (fns) == IDENTIFIER_NODE,
3870 if (BASELINK_P (fns))
3872 BASELINK_FUNCTIONS (fns) = build (TEMPLATE_ID_EXPR,
3874 BASELINK_FUNCTIONS (fns),
3879 type = TREE_TYPE (fns);
3880 if (TREE_CODE (fns) == OVERLOAD || !type)
3881 type = unknown_type_node;
3883 return build (TEMPLATE_ID_EXPR, type, fns, arglist);
3886 /* Within the scope of a template class S<T>, the name S gets bound
3887 (in build_self_reference) to a TYPE_DECL for the class, not a
3888 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
3889 or one of its enclosing classes, and that type is a template,
3890 return the associated TEMPLATE_DECL. Otherwise, the original
3891 DECL is returned. */
3894 maybe_get_template_decl_from_type_decl (tree decl)
3896 return (decl != NULL_TREE
3897 && TREE_CODE (decl) == TYPE_DECL
3898 && DECL_ARTIFICIAL (decl)
3899 && CLASS_TYPE_P (TREE_TYPE (decl))
3900 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
3901 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
3904 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
3905 parameters, find the desired type.
3907 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
3909 IN_DECL, if non-NULL, is the template declaration we are trying to
3912 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
3913 the class we are looking up.
3915 Issue error and warning messages under control of COMPLAIN.
3917 If the template class is really a local class in a template
3918 function, then the FUNCTION_CONTEXT is the function in which it is
3919 being instantiated. */
3922 lookup_template_class (tree d1,
3927 tsubst_flags_t complain)
3929 tree template = NULL_TREE, parmlist;
3932 timevar_push (TV_NAME_LOOKUP);
3934 if (TREE_CODE (d1) == IDENTIFIER_NODE)
3936 if (IDENTIFIER_VALUE (d1)
3937 && DECL_TEMPLATE_TEMPLATE_PARM_P (IDENTIFIER_VALUE (d1)))
3938 template = IDENTIFIER_VALUE (d1);
3942 push_decl_namespace (context);
3943 template = lookup_name (d1, /*prefer_type=*/0);
3944 template = maybe_get_template_decl_from_type_decl (template);
3946 pop_decl_namespace ();
3949 context = DECL_CONTEXT (template);
3951 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
3953 tree type = TREE_TYPE (d1);
3955 /* If we are declaring a constructor, say A<T>::A<T>, we will get
3956 an implicit typename for the second A. Deal with it. */
3957 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
3958 type = TREE_TYPE (type);
3960 if (CLASSTYPE_TEMPLATE_INFO (type))
3962 template = CLASSTYPE_TI_TEMPLATE (type);
3963 d1 = DECL_NAME (template);
3966 else if (TREE_CODE (d1) == ENUMERAL_TYPE
3967 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
3969 template = TYPE_TI_TEMPLATE (d1);
3970 d1 = DECL_NAME (template);
3972 else if (TREE_CODE (d1) == TEMPLATE_DECL
3973 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
3976 d1 = DECL_NAME (template);
3977 context = DECL_CONTEXT (template);
3980 /* With something like `template <class T> class X class X { ... };'
3981 we could end up with D1 having nothing but an IDENTIFIER_VALUE.
3982 We don't want to do that, but we have to deal with the situation,
3983 so let's give them some syntax errors to chew on instead of a
3984 crash. Alternatively D1 might not be a template type at all. */
3987 if (complain & tf_error)
3988 error ("`%T' is not a template", d1);
3989 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
3992 if (TREE_CODE (template) != TEMPLATE_DECL
3993 /* Make sure it's a user visible template, if it was named by
3995 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
3996 && !PRIMARY_TEMPLATE_P (template)))
3998 if (complain & tf_error)
4000 error ("non-template type `%T' used as a template", d1);
4002 cp_error_at ("for template declaration `%D'", in_decl);
4004 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4007 complain &= ~tf_user;
4009 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4011 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4012 template arguments */
4017 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4019 /* Consider an example where a template template parameter declared as
4021 template <class T, class U = std::allocator<T> > class TT
4023 The template parameter level of T and U are one level larger than
4024 of TT. To proper process the default argument of U, say when an
4025 instantiation `TT<int>' is seen, we need to build the full
4026 arguments containing {int} as the innermost level. Outer levels,
4027 available when not appearing as default template argument, can be
4028 obtained from `current_template_args ()'.
4030 Suppose that TT is later substituted with std::vector. The above
4031 instantiation is `TT<int, std::allocator<T> >' with TT at
4032 level 1, and T at level 2, while the template arguments at level 1
4033 becomes {std::vector} and the inner level 2 is {int}. */
4035 if (current_template_parms)
4036 arglist = add_to_template_args (current_template_args (), arglist);
4038 arglist2 = coerce_template_parms (parmlist, arglist, template,
4039 complain, /*require_all_args=*/1);
4040 if (arglist2 == error_mark_node
4041 || (!uses_template_parms (arglist2)
4042 && check_instantiated_args (template, arglist2, complain)))
4043 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4045 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4046 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4050 tree template_type = TREE_TYPE (template);
4053 tree found = NULL_TREE;
4057 int is_partial_instantiation;
4059 gen_tmpl = most_general_template (template);
4060 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4061 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4062 arg_depth = TMPL_ARGS_DEPTH (arglist);
4064 if (arg_depth == 1 && parm_depth > 1)
4066 /* We've been given an incomplete set of template arguments.
4069 template <class T> struct S1 {
4070 template <class U> struct S2 {};
4071 template <class U> struct S2<U*> {};
4074 we will be called with an ARGLIST of `U*', but the
4075 TEMPLATE will be `template <class T> template
4076 <class U> struct S1<T>::S2'. We must fill in the missing
4079 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4081 arg_depth = TMPL_ARGS_DEPTH (arglist);
4084 /* Now we should have enough arguments. */
4085 my_friendly_assert (parm_depth == arg_depth, 0);
4087 /* From here on, we're only interested in the most general
4089 template = gen_tmpl;
4091 /* Calculate the BOUND_ARGS. These will be the args that are
4092 actually tsubst'd into the definition to create the
4096 /* We have multiple levels of arguments to coerce, at once. */
4098 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4100 tree bound_args = make_tree_vec (parm_depth);
4102 for (i = saved_depth,
4103 t = DECL_TEMPLATE_PARMS (template);
4104 i > 0 && t != NULL_TREE;
4105 --i, t = TREE_CHAIN (t))
4107 tree a = coerce_template_parms (TREE_VALUE (t),
4109 complain, /*require_all_args=*/1);
4111 /* Don't process further if one of the levels fails. */
4112 if (a == error_mark_node)
4114 /* Restore the ARGLIST to its full size. */
4115 TREE_VEC_LENGTH (arglist) = saved_depth;
4116 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4119 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4121 /* We temporarily reduce the length of the ARGLIST so
4122 that coerce_template_parms will see only the arguments
4123 corresponding to the template parameters it is
4125 TREE_VEC_LENGTH (arglist)--;
4128 /* Restore the ARGLIST to its full size. */
4129 TREE_VEC_LENGTH (arglist) = saved_depth;
4131 arglist = bound_args;
4135 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4136 INNERMOST_TEMPLATE_ARGS (arglist),
4138 complain, /*require_all_args=*/1);
4140 if (arglist == error_mark_node
4141 || (!uses_template_parms (INNERMOST_TEMPLATE_ARGS (arglist))
4142 && check_instantiated_args (template,
4143 INNERMOST_TEMPLATE_ARGS (arglist),
4145 /* We were unable to bind the arguments. */
4146 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4148 /* In the scope of a template class, explicit references to the
4149 template class refer to the type of the template, not any
4150 instantiation of it. For example, in:
4152 template <class T> class C { void f(C<T>); }
4154 the `C<T>' is just the same as `C'. Outside of the
4155 class, however, such a reference is an instantiation. */
4156 if (comp_template_args (TYPE_TI_ARGS (template_type),
4159 found = template_type;
4161 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4165 for (ctx = current_class_type;
4167 ctx = TYPE_CONTEXT (ctx))
4169 if (TREE_CODE (ctx) == NAMESPACE_DECL)
4171 if (same_type_p (ctx, template_type))
4175 /* We're not in the scope of the class, so the
4176 TEMPLATE_TYPE is not the type we want after all. */
4182 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4184 for (tp = &DECL_TEMPLATE_INSTANTIATIONS (template);
4186 tp = &TREE_CHAIN (*tp))
4187 if (comp_template_args (TREE_PURPOSE (*tp), arglist))
4191 /* Use the move-to-front heuristic to speed up future
4193 *tp = TREE_CHAIN (*tp);
4195 = DECL_TEMPLATE_INSTANTIATIONS (template);
4196 DECL_TEMPLATE_INSTANTIATIONS (template) = found;
4198 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, TREE_VALUE (found));
4201 /* This type is a "partial instantiation" if any of the template
4202 arguments still involve template parameters. Note that we set
4203 IS_PARTIAL_INSTANTIATION for partial specializations as
4205 is_partial_instantiation = uses_template_parms (arglist);
4207 if (!is_partial_instantiation
4208 && !PRIMARY_TEMPLATE_P (template)
4209 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4211 found = xref_tag_from_type (TREE_TYPE (template),
4212 DECL_NAME (template),
4214 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4217 context = tsubst (DECL_CONTEXT (template), arglist,
4220 context = global_namespace;
4222 /* Create the type. */
4223 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4225 if (!is_partial_instantiation)
4227 set_current_access_from_decl (TYPE_NAME (template_type));
4228 t = start_enum (TYPE_IDENTIFIER (template_type));
4231 /* We don't want to call start_enum for this type, since
4232 the values for the enumeration constants may involve
4233 template parameters. And, no one should be interested
4234 in the enumeration constants for such a type. */
4235 t = make_node (ENUMERAL_TYPE);
4239 t = make_aggr_type (TREE_CODE (template_type));
4240 CLASSTYPE_DECLARED_CLASS (t)
4241 = CLASSTYPE_DECLARED_CLASS (template_type);
4242 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4243 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4245 /* A local class. Make sure the decl gets registered properly. */
4246 if (context == current_function_decl)
4247 pushtag (DECL_NAME (template), t, 0);
4250 /* If we called start_enum or pushtag above, this information
4251 will already be set up. */
4254 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4256 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4257 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4258 TYPE_STUB_DECL (t) = type_decl;
4259 DECL_SOURCE_LOCATION (type_decl)
4260 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4263 type_decl = TYPE_NAME (t);
4265 TREE_PRIVATE (type_decl)
4266 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4267 TREE_PROTECTED (type_decl)
4268 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4270 /* Set up the template information. We have to figure out which
4271 template is the immediate parent if this is a full
4273 if (parm_depth == 1 || is_partial_instantiation
4274 || !PRIMARY_TEMPLATE_P (template))
4275 /* This case is easy; there are no member templates involved. */
4279 /* This is a full instantiation of a member template. Look
4280 for a partial instantiation of which this is an instance. */
4282 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4283 found; found = TREE_CHAIN (found))
4286 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4288 /* We only want partial instantiations, here, not
4289 specializations or full instantiations. */
4290 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4291 || !uses_template_parms (TREE_VALUE (found)))
4294 /* Temporarily reduce by one the number of levels in the
4295 ARGLIST and in FOUND so as to avoid comparing the
4296 last set of arguments. */
4297 TREE_VEC_LENGTH (arglist)--;
4298 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4300 /* See if the arguments match. If they do, then TMPL is
4301 the partial instantiation we want. */
4302 success = comp_template_args (TREE_PURPOSE (found), arglist);
4304 /* Restore the argument vectors to their full size. */
4305 TREE_VEC_LENGTH (arglist)++;
4306 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4317 /* There was no partial instantiation. This happens
4318 where C<T> is a member template of A<T> and it's used
4321 template <typename T> struct B { A<T>::C<int> m; };
4324 Create the partial instantiation.
4326 TREE_VEC_LENGTH (arglist)--;
4327 found = tsubst (template, arglist, complain, NULL_TREE);
4328 TREE_VEC_LENGTH (arglist)++;
4332 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4333 DECL_TEMPLATE_INSTANTIATIONS (template)
4334 = tree_cons (arglist, t,
4335 DECL_TEMPLATE_INSTANTIATIONS (template));
4337 if (TREE_CODE (t) == ENUMERAL_TYPE
4338 && !is_partial_instantiation)
4339 /* Now that the type has been registered on the instantiations
4340 list, we set up the enumerators. Because the enumeration
4341 constants may involve the enumeration type itself, we make
4342 sure to register the type first, and then create the
4343 constants. That way, doing tsubst_expr for the enumeration
4344 constants won't result in recursive calls here; we'll find
4345 the instantiation and exit above. */
4346 tsubst_enum (template_type, t, arglist);
4348 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4350 if (TREE_CODE (t) != ENUMERAL_TYPE)
4351 DECL_NAME (type_decl) = classtype_mangled_name (t);
4352 if (!is_partial_instantiation)
4354 /* For backwards compatibility; code that uses
4355 -fexternal-templates expects looking up a template to
4356 instantiate it. I think DDD still relies on this.
4357 (jason 8/20/1998) */
4358 if (TREE_CODE (t) != ENUMERAL_TYPE
4359 && flag_external_templates
4360 && CLASSTYPE_INTERFACE_KNOWN (TREE_TYPE (template))
4361 && ! CLASSTYPE_INTERFACE_ONLY (TREE_TYPE (template)))
4362 add_pending_template (t);
4365 /* If the type makes use of template parameters, the
4366 code that generates debugging information will crash. */
4367 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4369 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4371 timevar_pop (TV_NAME_LOOKUP);
4381 /* Called from for_each_template_parm via walk_tree. */
4384 for_each_template_parm_r (tree* tp, int* walk_subtrees, void* d)
4387 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4388 tree_fn_t fn = pfd->fn;
4389 void *data = pfd->data;
4392 /* If we have already visited this tree, there's no need to walk
4393 subtrees. Otherwise, add it to the visited table. */
4394 slot = htab_find_slot (pfd->visited, *tp, INSERT);
4403 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4404 return error_mark_node;
4406 switch (TREE_CODE (t))
4409 if (TYPE_PTRMEMFUNC_P (t))
4415 if (!TYPE_TEMPLATE_INFO (t))
4417 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4418 fn, data, pfd->visited))
4419 return error_mark_node;
4423 /* Since we're not going to walk subtrees, we have to do this
4425 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4427 return error_mark_node;
4431 /* Check the return type. */
4432 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4433 return error_mark_node;
4435 /* Check the parameter types. Since default arguments are not
4436 instantiated until they are needed, the TYPE_ARG_TYPES may
4437 contain expressions that involve template parameters. But,
4438 no-one should be looking at them yet. And, once they're
4439 instantiated, they don't contain template parameters, so
4440 there's no point in looking at them then, either. */
4444 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4445 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4447 return error_mark_node;
4449 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4450 want walk_tree walking into them itself. */
4456 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4458 return error_mark_node;
4463 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4464 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4466 return error_mark_node;
4471 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4472 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4474 return error_mark_node;
4475 if (DECL_CONTEXT (t)
4476 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4478 return error_mark_node;
4481 case BOUND_TEMPLATE_TEMPLATE_PARM:
4482 /* Record template parameters such as `T' inside `TT<T>'. */
4483 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4484 return error_mark_node;
4487 case TEMPLATE_TEMPLATE_PARM:
4488 case TEMPLATE_TYPE_PARM:
4489 case TEMPLATE_PARM_INDEX:
4490 if (fn && (*fn)(t, data))
4491 return error_mark_node;
4493 return error_mark_node;
4497 /* A template template parameter is encountered */
4498 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4499 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4500 return error_mark_node;
4502 /* Already substituted template template parameter */
4508 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4509 data, pfd->visited))
4510 return error_mark_node;
4514 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4515 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4516 (TREE_TYPE (t)), fn, data,
4518 return error_mark_node;
4523 /* If there's no type, then this thing must be some expression
4524 involving template parameters. */
4525 if (!fn && !TREE_TYPE (t))
4526 return error_mark_node;
4531 case REINTERPRET_CAST_EXPR:
4532 case CONST_CAST_EXPR:
4533 case STATIC_CAST_EXPR:
4534 case DYNAMIC_CAST_EXPR:
4538 case PSEUDO_DTOR_EXPR:
4540 return error_mark_node;
4544 /* If we do not handle this case specially, we end up walking
4545 the BINFO hierarchy, which is circular, and therefore
4546 confuses walk_tree. */
4548 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4550 return error_mark_node;
4557 /* We didn't find any template parameters we liked. */
4561 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4562 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4563 call FN with the parameter and the DATA.
4564 If FN returns nonzero, the iteration is terminated, and
4565 for_each_template_parm returns 1. Otherwise, the iteration
4566 continues. If FN never returns a nonzero value, the value
4567 returned by for_each_template_parm is 0. If FN is NULL, it is
4568 considered to be the function which always returns 1. */
4571 for_each_template_parm (tree t, tree_fn_t fn, void* data, htab_t visited)
4573 struct pair_fn_data pfd;
4580 /* Walk the tree. (Conceptually, we would like to walk without
4581 duplicates, but for_each_template_parm_r recursively calls
4582 for_each_template_parm, so we would need to reorganize a fair
4583 bit to use walk_tree_without_duplicates, so we keep our own
4586 pfd.visited = visited;
4588 pfd.visited = htab_create (37, htab_hash_pointer, htab_eq_pointer,
4590 result = walk_tree (&t,
4591 for_each_template_parm_r,
4597 htab_delete (pfd.visited);
4603 uses_template_parms (tree t)
4605 return for_each_template_parm (t, 0, 0, NULL);
4608 static int tinst_depth;
4609 extern int max_tinst_depth;
4610 #ifdef GATHER_STATISTICS
4613 static int tinst_level_tick;
4614 static int last_template_error_tick;
4616 /* We're starting to instantiate D; record the template instantiation context
4617 for diagnostics and to restore it later. */
4620 push_tinst_level (tree d)
4624 if (tinst_depth >= max_tinst_depth)
4626 /* If the instantiation in question still has unbound template parms,
4627 we don't really care if we can't instantiate it, so just return.
4628 This happens with base instantiation for implicit `typename'. */
4629 if (uses_template_parms (d))
4632 last_template_error_tick = tinst_level_tick;
4633 error ("template instantiation depth exceeds maximum of %d (use -ftemplate-depth-NN to increase the maximum) instantiating `%D'",
4634 max_tinst_depth, d);
4636 print_instantiation_context ();
4641 new = build_expr_wfl (d, input_filename, input_line, 0);
4642 TREE_CHAIN (new) = current_tinst_level;
4643 current_tinst_level = new;
4646 #ifdef GATHER_STATISTICS
4647 if (tinst_depth > depth_reached)
4648 depth_reached = tinst_depth;
4655 /* We're done instantiating this template; return to the instantiation
4659 pop_tinst_level (void)
4661 tree old = current_tinst_level;
4663 /* Restore the filename and line number stashed away when we started
4664 this instantiation. */
4665 input_line = TINST_LINE (old);
4666 input_filename = TINST_FILE (old);
4667 extract_interface_info ();
4669 current_tinst_level = TREE_CHAIN (old);
4674 /* We're instantiating a deferred template; restore the template
4675 instantiation context in which the instantiation was requested, which
4676 is one step out from LEVEL. */
4679 reopen_tinst_level (tree level)
4684 for (t = level; t; t = TREE_CHAIN (t))
4687 current_tinst_level = level;
4691 /* Return the outermost template instantiation context, for use with
4692 -falt-external-templates. */
4695 tinst_for_decl (void)
4697 tree p = current_tinst_level;
4700 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
4705 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4706 vector of template arguments, as for tsubst.
4708 Returns an appropriate tsubst'd friend declaration. */
4711 tsubst_friend_function (tree decl, tree args)
4714 location_t saved_loc = input_location;
4716 input_location = DECL_SOURCE_LOCATION (decl);
4718 if (TREE_CODE (decl) == FUNCTION_DECL
4719 && DECL_TEMPLATE_INSTANTIATION (decl)
4720 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
4721 /* This was a friend declared with an explicit template
4722 argument list, e.g.:
4726 to indicate that f was a template instantiation, not a new
4727 function declaration. Now, we have to figure out what
4728 instantiation of what template. */
4730 tree template_id, arglist, fns;
4733 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
4735 /* Friend functions are looked up in the containing namespace scope.
4736 We must enter that scope, to avoid finding member functions of the
4737 current cless with same name. */
4738 push_nested_namespace (ns);
4739 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
4740 tf_error | tf_warning, NULL_TREE);
4741 pop_nested_namespace (ns);
4742 arglist = tsubst (DECL_TI_ARGS (decl), args,
4743 tf_error | tf_warning, NULL_TREE);
4744 template_id = lookup_template_function (fns, arglist);
4746 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
4747 tmpl = determine_specialization (template_id, new_friend,
4749 /*need_member_template=*/0);
4750 new_friend = instantiate_template (tmpl, new_args, tf_error);
4754 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
4756 /* The NEW_FRIEND will look like an instantiation, to the
4757 compiler, but is not an instantiation from the point of view of
4758 the language. For example, we might have had:
4760 template <class T> struct S {
4761 template <class U> friend void f(T, U);
4764 Then, in S<int>, template <class U> void f(int, U) is not an
4765 instantiation of anything. */
4766 DECL_USE_TEMPLATE (new_friend) = 0;
4767 if (TREE_CODE (decl) == TEMPLATE_DECL)
4769 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
4770 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
4771 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
4774 /* The mangled name for the NEW_FRIEND is incorrect. The function
4775 is not a template instantiation and should not be mangled like
4776 one. Therefore, we forget the mangling here; we'll recompute it
4777 later if we need it. */
4778 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
4780 SET_DECL_RTL (new_friend, NULL_RTX);
4781 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
4784 if (DECL_NAMESPACE_SCOPE_P (new_friend))
4787 tree new_friend_template_info;
4788 tree new_friend_result_template_info;
4790 int new_friend_is_defn;
4792 /* We must save some information from NEW_FRIEND before calling
4793 duplicate decls since that function will free NEW_FRIEND if
4795 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
4796 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
4798 /* This declaration is a `primary' template. */
4799 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
4802 = DECL_INITIAL (DECL_TEMPLATE_RESULT (new_friend)) != NULL_TREE;
4803 new_friend_result_template_info
4804 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
4808 new_friend_is_defn = DECL_INITIAL (new_friend) != NULL_TREE;
4809 new_friend_result_template_info = NULL_TREE;
4812 /* Inside pushdecl_namespace_level, we will push into the
4813 current namespace. However, the friend function should go
4814 into the namespace of the template. */
4815 ns = decl_namespace_context (new_friend);
4816 push_nested_namespace (ns);
4817 old_decl = pushdecl_namespace_level (new_friend);
4818 pop_nested_namespace (ns);
4820 if (old_decl != new_friend)
4822 /* This new friend declaration matched an existing
4823 declaration. For example, given:
4825 template <class T> void f(T);
4826 template <class U> class C {
4827 template <class T> friend void f(T) {}
4830 the friend declaration actually provides the definition
4831 of `f', once C has been instantiated for some type. So,
4832 old_decl will be the out-of-class template declaration,
4833 while new_friend is the in-class definition.
4835 But, if `f' was called before this point, the
4836 instantiation of `f' will have DECL_TI_ARGS corresponding
4837 to `T' but not to `U', references to which might appear
4838 in the definition of `f'. Previously, the most general
4839 template for an instantiation of `f' was the out-of-class
4840 version; now it is the in-class version. Therefore, we
4841 run through all specialization of `f', adding to their
4842 DECL_TI_ARGS appropriately. In particular, they need a
4843 new set of outer arguments, corresponding to the
4844 arguments for this class instantiation.
4846 The same situation can arise with something like this:
4849 template <class T> class C {
4853 when `C<int>' is instantiated. Now, `f(int)' is defined
4856 if (!new_friend_is_defn)
4857 /* On the other hand, if the in-class declaration does
4858 *not* provide a definition, then we don't want to alter
4859 existing definitions. We can just leave everything
4864 /* Overwrite whatever template info was there before, if
4865 any, with the new template information pertaining to
4867 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
4869 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
4870 reregister_specialization (new_friend,
4871 most_general_template (old_decl),
4876 tree new_friend_args;
4878 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
4879 = new_friend_result_template_info;
4881 new_friend_args = TI_ARGS (new_friend_template_info);
4882 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
4886 tree spec = TREE_VALUE (t);
4889 = add_outermost_template_args (new_friend_args,
4890 DECL_TI_ARGS (spec));
4893 /* Now, since specializations are always supposed to
4894 hang off of the most general template, we must move
4896 t = most_general_template (old_decl);
4899 DECL_TEMPLATE_SPECIALIZATIONS (t)
4900 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
4901 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
4902 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
4907 /* The information from NEW_FRIEND has been merged into OLD_DECL
4908 by duplicate_decls. */
4909 new_friend = old_decl;
4912 else if (COMPLETE_TYPE_P (DECL_CONTEXT (new_friend)))
4914 /* Check to see that the declaration is really present, and,
4915 possibly obtain an improved declaration. */
4916 tree fn = check_classfn (DECL_CONTEXT (new_friend),
4924 input_location = saved_loc;
4928 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
4929 template arguments, as for tsubst.
4931 Returns an appropriate tsubst'd friend type or error_mark_node on
4935 tsubst_friend_class (tree friend_tmpl, tree args)
4941 context = DECL_CONTEXT (friend_tmpl);
4945 if (TREE_CODE (context) == NAMESPACE_DECL)
4946 push_nested_namespace (context);
4948 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
4951 /* First, we look for a class template. */
4952 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
4954 /* But, if we don't find one, it might be because we're in a
4955 situation like this:
4963 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
4964 for `S<int>', not the TEMPLATE_DECL. */
4965 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
4967 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
4968 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
4971 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
4973 /* The friend template has already been declared. Just
4974 check to see that the declarations match, and install any new
4975 default parameters. We must tsubst the default parameters,
4976 of course. We only need the innermost template parameters
4977 because that is all that redeclare_class_template will look
4979 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
4980 > TMPL_ARGS_DEPTH (args))
4983 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
4984 args, tf_error | tf_warning);
4985 redeclare_class_template (TREE_TYPE (tmpl), parms);
4988 friend_type = TREE_TYPE (tmpl);
4992 /* The friend template has not already been declared. In this
4993 case, the instantiation of the template class will cause the
4994 injection of this template into the global scope. */
4995 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
4997 /* The new TMPL is not an instantiation of anything, so we
4998 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
4999 the new type because that is supposed to be the corresponding
5000 template decl, i.e., TMPL. */
5001 DECL_USE_TEMPLATE (tmpl) = 0;
5002 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5003 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5004 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5005 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5007 /* Inject this template into the global scope. */
5008 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5013 if (TREE_CODE (context) == NAMESPACE_DECL)
5014 pop_nested_namespace (context);
5016 pop_nested_class ();
5022 /* Returns zero if TYPE cannot be completed later due to circularity.
5023 Otherwise returns one. */
5026 can_complete_type_without_circularity (tree type)
5028 if (type == NULL_TREE || type == error_mark_node)
5030 else if (COMPLETE_TYPE_P (type))
5032 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5033 return can_complete_type_without_circularity (TREE_TYPE (type));
5034 else if (CLASS_TYPE_P (type)
5035 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5042 instantiate_class_template (tree type)
5044 tree template, args, pattern, t, member;
5048 if (type == error_mark_node)
5049 return error_mark_node;
5051 if (TYPE_BEING_DEFINED (type)
5052 || COMPLETE_TYPE_P (type)
5053 || dependent_type_p (type))
5056 /* Figure out which template is being instantiated. */
5057 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5058 my_friendly_assert (TREE_CODE (template) == TEMPLATE_DECL, 279);
5060 /* Figure out which arguments are being used to do the
5062 args = CLASSTYPE_TI_ARGS (type);
5064 /* Determine what specialization of the original template to
5066 t = most_specialized_class (template, args);
5067 if (t == error_mark_node)
5069 const char *str = "candidates are:";
5070 error ("ambiguous class template instantiation for `%#T'", type);
5071 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5074 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5076 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5080 TYPE_BEING_DEFINED (type) = 1;
5081 return error_mark_node;
5085 pattern = TREE_TYPE (t);
5087 pattern = TREE_TYPE (template);
5089 /* If the template we're instantiating is incomplete, then clearly
5090 there's nothing we can do. */
5091 if (!COMPLETE_TYPE_P (pattern))
5094 /* If we've recursively instantiated too many templates, stop. */
5095 if (! push_tinst_level (type))
5098 /* Now we're really doing the instantiation. Mark the type as in
5099 the process of being defined. */
5100 TYPE_BEING_DEFINED (type) = 1;
5102 /* We may be in the middle of deferred access check. Disable
5104 push_deferring_access_checks (dk_no_deferred);
5106 maybe_push_to_top_level (uses_template_parms (type));
5110 /* This TYPE is actually an instantiation of a partial
5111 specialization. We replace the innermost set of ARGS with
5112 the arguments appropriate for substitution. For example,
5115 template <class T> struct S {};
5116 template <class T> struct S<T*> {};
5118 and supposing that we are instantiating S<int*>, ARGS will
5119 present be {int*} but we need {int}. */
5121 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5124 /* If there were multiple levels in ARGS, replacing the
5125 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5126 want, so we make a copy first. */
5127 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5129 args = copy_node (args);
5130 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5136 if (flag_external_templates)
5138 if (flag_alt_external_templates)
5140 CLASSTYPE_INTERFACE_ONLY (type) = interface_only;
5141 SET_CLASSTYPE_INTERFACE_UNKNOWN_X (type, interface_unknown);
5145 CLASSTYPE_INTERFACE_ONLY (type) = CLASSTYPE_INTERFACE_ONLY (pattern);
5146 SET_CLASSTYPE_INTERFACE_UNKNOWN_X
5147 (type, CLASSTYPE_INTERFACE_UNKNOWN (pattern));
5152 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5155 /* Set the input location to the template definition. This is needed
5156 if tsubsting causes an error. */
5157 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (pattern));
5159 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5160 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5161 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5162 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5163 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5164 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5165 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5166 TYPE_HAS_ABSTRACT_ASSIGN_REF (type) = TYPE_HAS_ABSTRACT_ASSIGN_REF (pattern);
5167 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5168 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5169 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5170 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5171 TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
5172 = TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (pattern);
5173 TYPE_USES_MULTIPLE_INHERITANCE (type)
5174 = TYPE_USES_MULTIPLE_INHERITANCE (pattern);
5175 TYPE_USES_VIRTUAL_BASECLASSES (type)
5176 = TYPE_USES_VIRTUAL_BASECLASSES (pattern);
5177 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5178 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5179 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5180 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5181 if (ANON_AGGR_TYPE_P (pattern))
5182 SET_ANON_AGGR_TYPE_P (type);
5184 pbinfo = TYPE_BINFO (pattern);
5186 if (BINFO_BASETYPES (pbinfo))
5188 tree base_list = NULL_TREE;
5189 tree pbases = BINFO_BASETYPES (pbinfo);
5190 tree paccesses = BINFO_BASEACCESSES (pbinfo);
5191 tree context = TYPE_CONTEXT (type);
5194 /* We must enter the scope containing the type, as that is where
5195 the accessibility of types named in dependent bases are
5197 push_scope (context ? context : global_namespace);
5199 /* Substitute into each of the bases to determine the actual
5201 for (i = 0; i < TREE_VEC_LENGTH (pbases); ++i)
5207 pbase = TREE_VEC_ELT (pbases, i);
5208 access = TREE_VEC_ELT (paccesses, i);
5210 /* Substitute to figure out the base class. */
5211 base = tsubst (BINFO_TYPE (pbase), args, tf_error, NULL_TREE);
5212 if (base == error_mark_node)
5215 base_list = tree_cons (access, base, base_list);
5216 TREE_VIA_VIRTUAL (base_list) = TREE_VIA_VIRTUAL (pbase);
5219 /* The list is now in reverse order; correct that. */
5220 base_list = nreverse (base_list);
5222 /* Now call xref_basetypes to set up all the base-class
5224 xref_basetypes (type, base_list);
5226 pop_scope (context ? context : global_namespace);
5229 /* Now that our base classes are set up, enter the scope of the
5230 class, so that name lookups into base classes, etc. will work
5231 correctly. This is precisely analogous to what we do in
5232 begin_class_definition when defining an ordinary non-template
5236 /* Now members are processed in the order of declaration. */
5237 for (member = CLASSTYPE_DECL_LIST (pattern);
5238 member; member = TREE_CHAIN (member))
5240 tree t = TREE_VALUE (member);
5242 if (TREE_PURPOSE (member))
5246 /* Build new CLASSTYPE_NESTED_UTDS. */
5249 tree name = TYPE_IDENTIFIER (tag);
5252 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5253 my_friendly_assert (newtag != error_mark_node, 20010206);
5254 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5256 if (TYPE_LANG_SPECIFIC (tag) && CLASSTYPE_IS_TEMPLATE (tag))
5257 /* Unfortunately, lookup_template_class sets
5258 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5259 instantiation (i.e., for the type of a member
5260 template class nested within a template class.)
5261 This behavior is required for
5262 maybe_process_partial_specialization to work
5263 correctly, but is not accurate in this case;
5264 the TAG is not an instantiation of anything.
5265 (The corresponding TEMPLATE_DECL is an
5266 instantiation, but the TYPE is not.) */
5267 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5269 /* Now, we call pushtag to put this NEWTAG into the scope of
5270 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5271 pushtag calling push_template_decl. We don't have to do
5272 this for enums because it will already have been done in
5275 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5276 pushtag (name, newtag, /*globalize=*/0);
5279 else if (TREE_CODE (t) == FUNCTION_DECL
5280 || DECL_FUNCTION_TEMPLATE_P (t))
5282 /* Build new TYPE_METHODS. */
5285 if (TREE_CODE (t) == TEMPLATE_DECL)
5286 processing_template_decl++;
5287 r = tsubst (t, args, tf_error, NULL_TREE);
5288 if (TREE_CODE (t) == TEMPLATE_DECL)
5289 processing_template_decl--;
5290 set_current_access_from_decl (r);
5291 grok_special_member_properties (r);
5292 finish_member_declaration (r);
5296 /* Build new TYPE_FIELDS. */
5298 if (TREE_CODE (t) != CONST_DECL)
5302 /* The the file and line for this declaration, to
5303 assist in error message reporting. Since we
5304 called push_tinst_level above, we don't need to
5306 input_location = DECL_SOURCE_LOCATION (t);
5308 if (TREE_CODE (t) == TEMPLATE_DECL)
5309 processing_template_decl++;
5310 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5311 if (TREE_CODE (t) == TEMPLATE_DECL)
5312 processing_template_decl--;
5313 if (TREE_CODE (r) == VAR_DECL)
5317 if (DECL_INITIALIZED_IN_CLASS_P (r))
5318 init = tsubst_expr (DECL_INITIAL (t), args,
5319 tf_error | tf_warning, NULL_TREE);
5323 finish_static_data_member_decl
5324 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5326 if (DECL_INITIALIZED_IN_CLASS_P (r))
5327 check_static_variable_definition (r, TREE_TYPE (r));
5329 else if (TREE_CODE (r) == FIELD_DECL)
5331 /* Determine whether R has a valid type and can be
5332 completed later. If R is invalid, then it is
5333 replaced by error_mark_node so that it will not be
5334 added to TYPE_FIELDS. */
5335 tree rtype = TREE_TYPE (r);
5336 if (can_complete_type_without_circularity (rtype))
5337 complete_type (rtype);
5339 if (!COMPLETE_TYPE_P (rtype))
5341 cxx_incomplete_type_error (r, rtype);
5342 r = error_mark_node;
5346 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5347 such a thing will already have been added to the field
5348 list by tsubst_enum in finish_member_declaration in the
5349 CLASSTYPE_NESTED_UTDS case above. */
5350 if (!(TREE_CODE (r) == TYPE_DECL
5351 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5352 && DECL_ARTIFICIAL (r)))
5354 set_current_access_from_decl (r);
5355 finish_member_declaration (r);
5362 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5364 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5366 tree friend_type = t;
5367 tree new_friend_type;
5369 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5370 new_friend_type = tsubst_friend_class (friend_type, args);
5371 else if (uses_template_parms (friend_type))
5372 new_friend_type = tsubst (friend_type, args,
5373 tf_error | tf_warning, NULL_TREE);
5374 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5375 new_friend_type = friend_type;
5378 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5380 /* The call to xref_tag_from_type does injection for friend
5382 push_nested_namespace (ns);
5384 xref_tag_from_type (friend_type, NULL_TREE, 1);
5385 pop_nested_namespace (ns);
5388 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5389 /* Trick make_friend_class into realizing that the friend
5390 we're adding is a template, not an ordinary class. It's
5391 important that we use make_friend_class since it will
5392 perform some error-checking and output cross-reference
5394 ++processing_template_decl;
5396 if (new_friend_type != error_mark_node)
5397 make_friend_class (type, new_friend_type,
5398 /*complain=*/false);
5400 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5401 --processing_template_decl;
5404 /* Build new DECL_FRIENDLIST. */
5405 add_friend (type, tsubst_friend_function (t, args),
5406 /*complain=*/false);
5410 /* Set the file and line number information to whatever is given for
5411 the class itself. This puts error messages involving generated
5412 implicit functions at a predictable point, and the same point
5413 that would be used for non-template classes. */
5414 typedecl = TYPE_MAIN_DECL (type);
5415 input_location = DECL_SOURCE_LOCATION (typedecl);
5417 unreverse_member_declarations (type);
5418 finish_struct_1 (type);
5420 /* Clear this now so repo_template_used is happy. */
5421 TYPE_BEING_DEFINED (type) = 0;
5422 repo_template_used (type);
5424 /* Now that the class is complete, instantiate default arguments for
5425 any member functions. We don't do this earlier because the
5426 default arguments may reference members of the class. */
5427 if (!PRIMARY_TEMPLATE_P (template))
5428 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5429 if (TREE_CODE (t) == FUNCTION_DECL
5430 /* Implicitly generated member functions will not have template
5431 information; they are not instantiations, but instead are
5432 created "fresh" for each instantiation. */
5433 && DECL_TEMPLATE_INFO (t))
5434 tsubst_default_arguments (t);
5437 pop_from_top_level ();
5438 pop_deferring_access_checks ();
5441 if (TYPE_CONTAINS_VPTR_P (type))
5442 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5448 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5454 else if (TYPE_P (t))
5455 r = tsubst (t, args, complain, in_decl);
5458 r = tsubst_expr (t, args, complain, in_decl);
5460 if (!uses_template_parms (r))
5462 /* Sometimes, one of the args was an expression involving a
5463 template constant parameter, like N - 1. Now that we've
5464 tsubst'd, we might have something like 2 - 1. This will
5465 confuse lookup_template_class, so we do constant folding
5466 here. We have to unset processing_template_decl, to fool
5467 tsubst_copy_and_build() into building an actual tree. */
5469 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5470 as simple as it's going to get, and trying to reprocess
5471 the trees will break. Once tsubst_expr et al DTRT for
5472 non-dependent exprs, this code can go away, as the type
5473 will always be set. */
5476 int saved_processing_template_decl = processing_template_decl;
5477 processing_template_decl = 0;
5478 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5479 tf_error, /*in_decl=*/NULL_TREE,
5480 /*function_p=*/false);
5481 processing_template_decl = saved_processing_template_decl;
5489 /* Substitute ARGS into the vector or list of template arguments T. */
5492 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5494 int len = TREE_VEC_LENGTH (t);
5495 int need_new = 0, i;
5496 tree *elts = alloca (len * sizeof (tree));
5498 for (i = 0; i < len; i++)
5500 tree orig_arg = TREE_VEC_ELT (t, i);
5503 if (TREE_CODE (orig_arg) == TREE_VEC)
5504 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5506 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5508 if (new_arg == error_mark_node)
5509 return error_mark_node;
5512 if (new_arg != orig_arg)
5519 t = make_tree_vec (len);
5520 for (i = 0; i < len; i++)
5521 TREE_VEC_ELT (t, i) = elts[i];
5526 /* Return the result of substituting ARGS into the template parameters
5527 given by PARMS. If there are m levels of ARGS and m + n levels of
5528 PARMS, then the result will contain n levels of PARMS. For
5529 example, if PARMS is `template <class T> template <class U>
5530 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5531 result will be `template <int*, double, class V>'. */
5534 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5539 for (new_parms = &r;
5540 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5541 new_parms = &(TREE_CHAIN (*new_parms)),
5542 parms = TREE_CHAIN (parms))
5545 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5548 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5550 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5551 tree default_value = TREE_PURPOSE (tuple);
5552 tree parm_decl = TREE_VALUE (tuple);
5554 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5555 default_value = tsubst_template_arg (default_value, args,
5556 complain, NULL_TREE);
5558 tuple = build_tree_list (default_value, parm_decl);
5559 TREE_VEC_ELT (new_vec, i) = tuple;
5563 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
5564 - TMPL_ARGS_DEPTH (args)),
5565 new_vec, NULL_TREE);
5571 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5572 type T. If T is not an aggregate or enumeration type, it is
5573 handled as if by tsubst. IN_DECL is as for tsubst. If
5574 ENTERING_SCOPE is nonzero, T is the context for a template which
5575 we are presently tsubst'ing. Return the substituted value. */
5578 tsubst_aggr_type (tree t,
5580 tsubst_flags_t complain,
5587 switch (TREE_CODE (t))
5590 if (TYPE_PTRMEMFUNC_P (t))
5591 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
5593 /* else fall through */
5596 if (TYPE_TEMPLATE_INFO (t))
5602 /* First, determine the context for the type we are looking
5604 context = TYPE_CONTEXT (t);
5606 context = tsubst_aggr_type (context, args, complain,
5607 in_decl, /*entering_scope=*/1);
5609 /* Then, figure out what arguments are appropriate for the
5610 type we are trying to find. For example, given:
5612 template <class T> struct S;
5613 template <class T, class U> void f(T, U) { S<U> su; }
5615 and supposing that we are instantiating f<int, double>,
5616 then our ARGS will be {int, double}, but, when looking up
5617 S we only want {double}. */
5618 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
5620 if (argvec == error_mark_node)
5621 return error_mark_node;
5623 r = lookup_template_class (t, argvec, in_decl, context,
5624 entering_scope, complain);
5626 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
5629 /* This is not a template type, so there's nothing to do. */
5633 return tsubst (t, args, complain, in_decl);
5637 /* Substitute into the default argument ARG (a default argument for
5638 FN), which has the indicated TYPE. */
5641 tsubst_default_argument (tree fn, tree type, tree arg)
5643 /* This default argument came from a template. Instantiate the
5644 default argument here, not in tsubst. In the case of
5653 we must be careful to do name lookup in the scope of S<T>,
5654 rather than in the current class.
5656 ??? current_class_type affects a lot more than name lookup. This is
5657 very fragile. Fortunately, it will go away when we do 2-phase name
5658 binding properly. */
5660 /* FN is already the desired FUNCTION_DECL. */
5661 push_access_scope (fn);
5663 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
5664 tf_error | tf_warning, NULL_TREE);
5666 pop_access_scope (fn);
5668 /* Make sure the default argument is reasonable. */
5669 arg = check_default_argument (type, arg);
5674 /* Substitute into all the default arguments for FN. */
5677 tsubst_default_arguments (tree fn)
5682 tmpl_args = DECL_TI_ARGS (fn);
5684 /* If this function is not yet instantiated, we certainly don't need
5685 its default arguments. */
5686 if (uses_template_parms (tmpl_args))
5689 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
5691 arg = TREE_CHAIN (arg))
5692 if (TREE_PURPOSE (arg))
5693 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
5695 TREE_PURPOSE (arg));
5698 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
5699 (already computed) substitution of ARGS into TREE_TYPE (T), if
5700 appropriate. Return the result of the substitution. Issue error
5701 and warning messages under control of COMPLAIN. */
5704 tsubst_decl (tree t, tree args, tree type, tsubst_flags_t complain)
5706 location_t saved_loc;
5710 /* Set the filename and linenumber to improve error-reporting. */
5711 saved_loc = input_location;
5712 input_location = DECL_SOURCE_LOCATION (t);
5714 switch (TREE_CODE (t))
5718 /* We can get here when processing a member template function
5719 of a template class. */
5720 tree decl = DECL_TEMPLATE_RESULT (t);
5722 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
5724 if (!is_template_template_parm)
5726 /* We might already have an instance of this template.
5727 The ARGS are for the surrounding class type, so the
5728 full args contain the tsubst'd args for the context,
5729 plus the innermost args from the template decl. */
5730 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
5731 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
5732 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
5735 full_args = tsubst_template_args (tmpl_args, args,
5738 /* tsubst_template_args doesn't copy the vector if
5739 nothing changed. But, *something* should have
5741 my_friendly_assert (full_args != tmpl_args, 0);
5743 spec = retrieve_specialization (t, full_args);
5744 if (spec != NULL_TREE)
5751 /* Make a new template decl. It will be similar to the
5752 original, but will record the current template arguments.
5753 We also create a new function declaration, which is just
5754 like the old one, but points to this new template, rather
5755 than the old one. */
5757 my_friendly_assert (DECL_LANG_SPECIFIC (r) != 0, 0);
5758 TREE_CHAIN (r) = NULL_TREE;
5760 if (is_template_template_parm)
5762 tree new_decl = tsubst (decl, args, complain, in_decl);
5763 DECL_TEMPLATE_RESULT (r) = new_decl;
5764 TREE_TYPE (r) = TREE_TYPE (new_decl);
5769 = tsubst_aggr_type (DECL_CONTEXT (t), args,
5771 /*entering_scope=*/1);
5772 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
5774 if (TREE_CODE (decl) == TYPE_DECL)
5776 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
5777 TREE_TYPE (r) = new_type;
5778 CLASSTYPE_TI_TEMPLATE (new_type) = r;
5779 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
5780 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
5784 tree new_decl = tsubst (decl, args, complain, in_decl);
5785 if (new_decl == error_mark_node)
5786 return error_mark_node;
5788 DECL_TEMPLATE_RESULT (r) = new_decl;
5789 DECL_TI_TEMPLATE (new_decl) = r;
5790 TREE_TYPE (r) = TREE_TYPE (new_decl);
5791 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
5794 SET_DECL_IMPLICIT_INSTANTIATION (r);
5795 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
5796 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
5798 /* The template parameters for this new template are all the
5799 template parameters for the old template, except the
5800 outermost level of parameters. */
5801 DECL_TEMPLATE_PARMS (r)
5802 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
5805 if (PRIMARY_TEMPLATE_P (t))
5806 DECL_PRIMARY_TEMPLATE (r) = r;
5808 if (TREE_CODE (decl) != TYPE_DECL)
5809 /* Record this non-type partial instantiation. */
5810 register_specialization (r, t,
5811 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
5818 tree argvec = NULL_TREE;
5825 /* Nobody should be tsubst'ing into non-template functions. */
5826 my_friendly_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE, 0);
5828 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
5833 /* If T is not dependent, just return it. We have to
5834 increment PROCESSING_TEMPLATE_DECL because
5835 value_dependent_expression_p assumes that nothing is
5836 dependent when PROCESSING_TEMPLATE_DECL is zero. */
5837 ++processing_template_decl;
5838 dependent_p = value_dependent_expression_p (t);
5839 --processing_template_decl;
5843 /* Calculate the most general template of which R is a
5844 specialization, and the complete set of arguments used to
5846 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
5847 argvec = tsubst_template_args (DECL_TI_ARGS
5848 (DECL_TEMPLATE_RESULT (gen_tmpl)),
5849 args, complain, in_decl);
5851 /* Check to see if we already have this specialization. */
5852 spec = retrieve_specialization (gen_tmpl, argvec);
5860 /* We can see more levels of arguments than parameters if
5861 there was a specialization of a member template, like
5864 template <class T> struct S { template <class U> void f(); }
5865 template <> template <class U> void S<int>::f(U);
5867 Here, we'll be substituting into the specialization,
5868 because that's where we can find the code we actually
5869 want to generate, but we'll have enough arguments for
5870 the most general template.
5872 We also deal with the peculiar case:
5874 template <class T> struct S {
5875 template <class U> friend void f();
5877 template <class U> void f() {}
5879 template void f<double>();
5881 Here, the ARGS for the instantiation of will be {int,
5882 double}. But, we only need as many ARGS as there are
5883 levels of template parameters in CODE_PATTERN. We are
5884 careful not to get fooled into reducing the ARGS in
5887 template <class T> struct S { template <class U> void f(U); }
5888 template <class T> template <> void S<T>::f(int) {}
5890 which we can spot because the pattern will be a
5891 specialization in this case. */
5892 args_depth = TMPL_ARGS_DEPTH (args);
5894 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
5895 if (args_depth > parms_depth
5896 && !DECL_TEMPLATE_SPECIALIZATION (t))
5897 args = get_innermost_template_args (args, parms_depth);
5901 /* This special case arises when we have something like this:
5903 template <class T> struct S {
5904 friend void f<int>(int, double);
5907 Here, the DECL_TI_TEMPLATE for the friend declaration
5908 will be an IDENTIFIER_NODE. We are being called from
5909 tsubst_friend_function, and we want only to create a
5910 new decl (R) with appropriate types so that we can call
5911 determine_specialization. */
5912 gen_tmpl = NULL_TREE;
5915 if (DECL_CLASS_SCOPE_P (t))
5917 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
5921 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
5922 complain, t, /*entering_scope=*/1);
5927 ctx = DECL_CONTEXT (t);
5929 type = tsubst (type, args, complain, in_decl);
5930 if (type == error_mark_node)
5931 return error_mark_node;
5933 /* We do NOT check for matching decls pushed separately at this
5934 point, as they may not represent instantiations of this
5935 template, and in any case are considered separate under the
5938 DECL_USE_TEMPLATE (r) = 0;
5939 TREE_TYPE (r) = type;
5940 /* Clear out the mangled name and RTL for the instantiation. */
5941 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
5942 SET_DECL_RTL (r, NULL_RTX);
5944 DECL_CONTEXT (r) = ctx;
5946 if (member && DECL_CONV_FN_P (r))
5947 /* Type-conversion operator. Reconstruct the name, in
5948 case it's the name of one of the template's parameters. */
5949 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
5951 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
5953 DECL_RESULT (r) = NULL_TREE;
5955 TREE_STATIC (r) = 0;
5956 TREE_PUBLIC (r) = TREE_PUBLIC (t);
5957 DECL_EXTERNAL (r) = 1;
5958 DECL_INTERFACE_KNOWN (r) = 0;
5959 DECL_DEFER_OUTPUT (r) = 0;
5960 TREE_CHAIN (r) = NULL_TREE;
5961 DECL_PENDING_INLINE_INFO (r) = 0;
5962 DECL_PENDING_INLINE_P (r) = 0;
5963 DECL_SAVED_TREE (r) = NULL_TREE;
5965 if (DECL_CLONED_FUNCTION (r))
5967 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
5969 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
5970 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
5973 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
5974 this in the special friend case mentioned above where
5975 GEN_TMPL is NULL. */
5978 DECL_TEMPLATE_INFO (r)
5979 = tree_cons (gen_tmpl, argvec, NULL_TREE);
5980 SET_DECL_IMPLICIT_INSTANTIATION (r);
5981 register_specialization (r, gen_tmpl, argvec);
5983 /* We're not supposed to instantiate default arguments
5984 until they are called, for a template. But, for a
5987 template <class T> void f ()
5988 { extern void g(int i = T()); }
5990 we should do the substitution when the template is
5991 instantiated. We handle the member function case in
5992 instantiate_class_template since the default arguments
5993 might refer to other members of the class. */
5995 && !PRIMARY_TEMPLATE_P (gen_tmpl)
5996 && !uses_template_parms (argvec))
5997 tsubst_default_arguments (r);
6000 /* Copy the list of befriending classes. */
6001 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6003 friends = &TREE_CHAIN (*friends))
6005 *friends = copy_node (*friends);
6006 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6011 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6013 maybe_retrofit_in_chrg (r);
6014 if (DECL_CONSTRUCTOR_P (r))
6015 grok_ctor_properties (ctx, r);
6016 /* If this is an instantiation of a member template, clone it.
6017 If it isn't, that'll be handled by
6018 clone_constructors_and_destructors. */
6019 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6020 clone_function_decl (r, /*update_method_vec_p=*/0);
6022 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6023 grok_op_properties (r, DECL_FRIEND_P (r),
6024 (complain & tf_error) != 0);
6031 if (DECL_TEMPLATE_PARM_P (t))
6032 SET_DECL_TEMPLATE_PARM_P (r);
6034 TREE_TYPE (r) = type;
6035 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6037 if (DECL_INITIAL (r))
6039 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6040 DECL_INITIAL (r) = TREE_TYPE (r);
6042 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6046 DECL_CONTEXT (r) = NULL_TREE;
6048 if (!DECL_TEMPLATE_PARM_P (r))
6049 DECL_ARG_TYPE (r) = type_passed_as (type);
6051 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6052 complain, TREE_CHAIN (t));
6059 TREE_TYPE (r) = type;
6060 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6062 /* We don't have to set DECL_CONTEXT here; it is set by
6063 finish_member_declaration. */
6064 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6066 TREE_CHAIN (r) = NULL_TREE;
6067 if (VOID_TYPE_P (type))
6068 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6075 /* It is not a dependent using decl any more. */
6076 TREE_TYPE (r) = void_type_node;
6078 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6080 = tsubst_copy (DECL_NAME (t), args, complain, in_decl);
6081 TREE_CHAIN (r) = NULL_TREE;
6086 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6087 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6089 /* If this is the canonical decl, we don't have to mess with
6090 instantiations, and often we can't (for typename, template
6091 type parms and such). Note that TYPE_NAME is not correct for
6092 the above test if we've copied the type for a typedef. */
6093 r = TYPE_NAME (type);
6101 tree argvec = NULL_TREE;
6102 tree gen_tmpl = NULL_TREE;
6104 tree tmpl = NULL_TREE;
6108 /* Assume this is a non-local variable. */
6111 if (TYPE_P (CP_DECL_CONTEXT (t)))
6112 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6114 in_decl, /*entering_scope=*/1);
6115 else if (DECL_NAMESPACE_SCOPE_P (t))
6116 ctx = DECL_CONTEXT (t);
6119 /* Subsequent calls to pushdecl will fill this in. */
6124 /* Check to see if we already have this specialization. */
6127 tmpl = DECL_TI_TEMPLATE (t);
6128 gen_tmpl = most_general_template (tmpl);
6129 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6130 spec = retrieve_specialization (gen_tmpl, argvec);
6133 spec = retrieve_local_specialization (t);
6142 if (TREE_CODE (r) == VAR_DECL)
6144 type = complete_type (type);
6145 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6146 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6148 else if (DECL_SELF_REFERENCE_P (t))
6149 SET_DECL_SELF_REFERENCE_P (r);
6150 TREE_TYPE (r) = type;
6151 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6152 DECL_CONTEXT (r) = ctx;
6153 /* Clear out the mangled name and RTL for the instantiation. */
6154 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6155 SET_DECL_RTL (r, NULL_RTX);
6157 /* Don't try to expand the initializer until someone tries to use
6158 this variable; otherwise we run into circular dependencies. */
6159 DECL_INITIAL (r) = NULL_TREE;
6160 SET_DECL_RTL (r, NULL_RTX);
6161 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6163 /* Even if the original location is out of scope, the newly
6164 substituted one is not. */
6165 if (TREE_CODE (r) == VAR_DECL)
6167 DECL_DEAD_FOR_LOCAL (r) = 0;
6168 DECL_INITIALIZED_P (r) = 0;
6173 /* A static data member declaration is always marked
6174 external when it is declared in-class, even if an
6175 initializer is present. We mimic the non-template
6177 DECL_EXTERNAL (r) = 1;
6179 register_specialization (r, gen_tmpl, argvec);
6180 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6181 SET_DECL_IMPLICIT_INSTANTIATION (r);
6184 register_local_specialization (r, t);
6186 TREE_CHAIN (r) = NULL_TREE;
6187 if (TREE_CODE (r) == VAR_DECL && VOID_TYPE_P (type))
6188 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6189 /* Compute the size, alignment, etc. of R. */
6198 /* Restore the file and line information. */
6199 input_location = saved_loc;
6204 /* Substitute into the ARG_TYPES of a function type. */
6207 tsubst_arg_types (tree arg_types,
6209 tsubst_flags_t complain,
6212 tree remaining_arg_types;
6215 if (!arg_types || arg_types == void_list_node)
6218 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6219 args, complain, in_decl);
6220 if (remaining_arg_types == error_mark_node)
6221 return error_mark_node;
6223 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6224 if (type == error_mark_node)
6225 return error_mark_node;
6226 if (VOID_TYPE_P (type))
6228 if (complain & tf_error)
6230 error ("invalid parameter type `%T'", type);
6232 cp_error_at ("in declaration `%D'", in_decl);
6234 return error_mark_node;
6237 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6238 top-level qualifiers as required. */
6239 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6241 /* Note that we do not substitute into default arguments here. The
6242 standard mandates that they be instantiated only when needed,
6243 which is done in build_over_call. */
6244 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6245 remaining_arg_types);
6249 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6250 *not* handle the exception-specification for FNTYPE, because the
6251 initial substitution of explicitly provided template parameters
6252 during argument deduction forbids substitution into the
6253 exception-specification:
6257 All references in the function type of the function template to the
6258 corresponding template parameters are replaced by the specified tem-
6259 plate argument values. If a substitution in a template parameter or
6260 in the function type of the function template results in an invalid
6261 type, type deduction fails. [Note: The equivalent substitution in
6262 exception specifications is done only when the function is instanti-
6263 ated, at which point a program is ill-formed if the substitution
6264 results in an invalid type.] */
6267 tsubst_function_type (tree t,
6269 tsubst_flags_t complain,
6276 /* The TYPE_CONTEXT is not used for function/method types. */
6277 my_friendly_assert (TYPE_CONTEXT (t) == NULL_TREE, 0);
6279 /* Substitute the return type. */
6280 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6281 if (return_type == error_mark_node)
6282 return error_mark_node;
6284 /* Substitute the argument types. */
6285 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6287 if (arg_types == error_mark_node)
6288 return error_mark_node;
6290 /* Construct a new type node and return it. */
6291 if (TREE_CODE (t) == FUNCTION_TYPE)
6292 fntype = build_function_type (return_type, arg_types);
6295 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6296 if (! IS_AGGR_TYPE (r))
6300 Type deduction may fail for any of the following
6303 -- Attempting to create "pointer to member of T" when T
6304 is not a class type. */
6305 if (complain & tf_error)
6306 error ("creating pointer to member function of non-class type `%T'",
6308 return error_mark_node;
6311 fntype = build_method_type_directly (r, return_type,
6312 TREE_CHAIN (arg_types));
6314 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6315 fntype = build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6320 /* Substitute into the PARMS of a call-declarator. */
6323 tsubst_call_declarator_parms (tree parms,
6325 tsubst_flags_t complain,
6332 if (!parms || parms == void_list_node)
6335 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6336 args, complain, in_decl);
6338 /* Figure out the type of this parameter. */
6339 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6341 /* Figure out the default argument as well. Note that we use
6342 tsubst_expr since the default argument is really an expression. */
6343 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6345 /* Chain this parameter on to the front of those we have already
6346 processed. We don't use hash_tree_cons because that function
6347 doesn't check TREE_PARMLIST. */
6348 new_parms = tree_cons (defarg, type, new_parms);
6350 /* And note that these are parameters. */
6351 TREE_PARMLIST (new_parms) = 1;
6356 /* Take the tree structure T and replace template parameters used
6357 therein with the argument vector ARGS. IN_DECL is an associated
6358 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6359 Issue error and warning messages under control of COMPLAIN. Note
6360 that we must be relatively non-tolerant of extensions here, in
6361 order to preserve conformance; if we allow substitutions that
6362 should not be allowed, we may allow argument deductions that should
6363 not succeed, and therefore report ambiguous overload situations
6364 where there are none. In theory, we could allow the substitution,
6365 but indicate that it should have failed, and allow our caller to
6366 make sure that the right thing happens, but we don't try to do this
6369 This function is used for dealing with types, decls and the like;
6370 for expressions, use tsubst_expr or tsubst_copy. */
6373 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6377 if (t == NULL_TREE || t == error_mark_node
6378 || t == integer_type_node
6379 || t == void_type_node
6380 || t == char_type_node
6381 || TREE_CODE (t) == NAMESPACE_DECL)
6384 if (TREE_CODE (t) == IDENTIFIER_NODE)
6385 type = IDENTIFIER_TYPE_VALUE (t);
6387 type = TREE_TYPE (t);
6389 my_friendly_assert (type != unknown_type_node, 20030716);
6391 if (type && TREE_CODE (t) != FUNCTION_DECL
6392 && TREE_CODE (t) != TYPENAME_TYPE
6393 && TREE_CODE (t) != TEMPLATE_DECL
6394 && TREE_CODE (t) != IDENTIFIER_NODE
6395 && TREE_CODE (t) != FUNCTION_TYPE
6396 && TREE_CODE (t) != METHOD_TYPE)
6397 type = tsubst (type, args, complain, in_decl);
6398 if (type == error_mark_node)
6399 return error_mark_node;
6402 return tsubst_decl (t, args, type, complain);
6404 switch (TREE_CODE (t))
6409 return tsubst_aggr_type (t, args, complain, in_decl,
6410 /*entering_scope=*/0);
6413 case IDENTIFIER_NODE:
6425 if (t == integer_type_node)
6428 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6429 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6433 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6435 /* The array dimension behaves like a non-type template arg,
6436 in that we want to fold it as much as possible. */
6437 max = tsubst_template_arg (omax, args, complain, in_decl);
6438 if (!processing_template_decl)
6439 max = decl_constant_value (max);
6441 if (processing_template_decl
6442 /* When providing explicit arguments to a template
6443 function, but leaving some arguments for subsequent
6444 deduction, MAX may be template-dependent even if we're
6445 not PROCESSING_TEMPLATE_DECL. We still need to check for
6446 template parms, though; MAX won't be an INTEGER_CST for
6447 dynamic arrays, either. */
6448 || (TREE_CODE (max) != INTEGER_CST
6449 && uses_template_parms (max)))
6451 tree itype = make_node (INTEGER_TYPE);
6452 TYPE_MIN_VALUE (itype) = size_zero_node;
6453 TYPE_MAX_VALUE (itype) = build_min (MINUS_EXPR, sizetype, max,
6458 if (integer_zerop (omax))
6460 /* Still allow an explicit array of size zero. */
6462 pedwarn ("creating array with size zero");
6464 else if (integer_zerop (max)
6465 || (TREE_CODE (max) == INTEGER_CST
6466 && INT_CST_LT (max, integer_zero_node)))
6470 Type deduction may fail for any of the following
6473 Attempting to create an array with a size that is
6474 zero or negative. */
6475 if (complain & tf_error)
6476 error ("creating array with size zero (`%E')", max);
6478 return error_mark_node;
6481 return compute_array_index_type (NULL_TREE, max);
6484 case TEMPLATE_TYPE_PARM:
6485 case TEMPLATE_TEMPLATE_PARM:
6486 case BOUND_TEMPLATE_TEMPLATE_PARM:
6487 case TEMPLATE_PARM_INDEX:
6495 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6496 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6497 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6499 idx = TEMPLATE_TYPE_IDX (t);
6500 level = TEMPLATE_TYPE_LEVEL (t);
6504 idx = TEMPLATE_PARM_IDX (t);
6505 level = TEMPLATE_PARM_LEVEL (t);
6508 if (TREE_VEC_LENGTH (args) > 0)
6510 tree arg = NULL_TREE;
6512 levels = TMPL_ARGS_DEPTH (args);
6513 if (level <= levels)
6514 arg = TMPL_ARG (args, level, idx);
6516 if (arg == error_mark_node)
6517 return error_mark_node;
6518 else if (arg != NULL_TREE)
6520 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6522 my_friendly_assert (TYPE_P (arg), 0);
6523 return cp_build_qualified_type_real
6524 (arg, cp_type_quals (arg) | cp_type_quals (t),
6525 complain | tf_ignore_bad_quals);
6527 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6529 /* We are processing a type constructed from
6530 a template template parameter */
6531 tree argvec = tsubst (TYPE_TI_ARGS (t),
6532 args, complain, in_decl);
6533 if (argvec == error_mark_node)
6534 return error_mark_node;
6536 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6537 we are resolving nested-types in the signature of
6538 a member function templates.
6539 Otherwise ARG is a TEMPLATE_DECL and is the real
6540 template to be instantiated. */
6541 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
6542 arg = TYPE_NAME (arg);
6544 r = lookup_template_class (arg,
6547 /*entering_scope=*/0,
6549 return cp_build_qualified_type_real
6550 (r, TYPE_QUALS (t), complain);
6553 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
6561 /* This can happen during the attempted tsubst'ing in
6562 unify. This means that we don't yet have any information
6563 about the template parameter in question. */
6566 /* If we get here, we must have been looking at a parm for a
6567 more deeply nested template. Make a new version of this
6568 template parameter, but with a lower level. */
6569 switch (TREE_CODE (t))
6571 case TEMPLATE_TYPE_PARM:
6572 case TEMPLATE_TEMPLATE_PARM:
6573 case BOUND_TEMPLATE_TEMPLATE_PARM:
6574 if (cp_type_quals (t))
6576 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
6577 r = cp_build_qualified_type_real
6578 (r, cp_type_quals (t),
6579 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6580 ? tf_ignore_bad_quals : 0));
6585 TEMPLATE_TYPE_PARM_INDEX (r)
6586 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
6588 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
6589 TYPE_MAIN_VARIANT (r) = r;
6590 TYPE_POINTER_TO (r) = NULL_TREE;
6591 TYPE_REFERENCE_TO (r) = NULL_TREE;
6593 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6595 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
6597 if (argvec == error_mark_node)
6598 return error_mark_node;
6600 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
6601 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
6606 case TEMPLATE_PARM_INDEX:
6607 r = reduce_template_parm_level (t, type, levels);
6619 tree purpose, value, chain, result;
6621 if (t == void_list_node)
6624 purpose = TREE_PURPOSE (t);
6627 purpose = tsubst (purpose, args, complain, in_decl);
6628 if (purpose == error_mark_node)
6629 return error_mark_node;
6631 value = TREE_VALUE (t);
6634 value = tsubst (value, args, complain, in_decl);
6635 if (value == error_mark_node)
6636 return error_mark_node;
6638 chain = TREE_CHAIN (t);
6639 if (chain && chain != void_type_node)
6641 chain = tsubst (chain, args, complain, in_decl);
6642 if (chain == error_mark_node)
6643 return error_mark_node;
6645 if (purpose == TREE_PURPOSE (t)
6646 && value == TREE_VALUE (t)
6647 && chain == TREE_CHAIN (t))
6649 if (TREE_PARMLIST (t))
6651 result = tree_cons (purpose, value, chain);
6652 TREE_PARMLIST (result) = 1;
6655 result = hash_tree_cons (purpose, value, chain);
6659 if (type != NULL_TREE)
6661 /* A binfo node. We always need to make a copy, of the node
6662 itself and of its BINFO_BASETYPES. */
6666 /* Make sure type isn't a typedef copy. */
6667 type = BINFO_TYPE (TYPE_BINFO (type));
6669 TREE_TYPE (t) = complete_type (type);
6670 if (IS_AGGR_TYPE (type))
6672 BINFO_VTABLE (t) = TYPE_BINFO_VTABLE (type);
6673 BINFO_VIRTUALS (t) = TYPE_BINFO_VIRTUALS (type);
6674 if (TYPE_BINFO_BASETYPES (type) != NULL_TREE)
6675 BINFO_BASETYPES (t) = copy_node (TYPE_BINFO_BASETYPES (type));
6680 /* Otherwise, a vector of template arguments. */
6681 return tsubst_template_args (t, args, complain, in_decl);
6684 case REFERENCE_TYPE:
6686 enum tree_code code;
6688 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
6691 code = TREE_CODE (t);
6696 Type deduction may fail for any of the following
6699 -- Attempting to create a pointer to reference type.
6700 -- Attempting to create a reference to a reference type or
6701 a reference to void. */
6702 if (TREE_CODE (type) == REFERENCE_TYPE
6703 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
6705 static location_t last_loc;
6707 /* We keep track of the last time we issued this error
6708 message to avoid spewing a ton of messages during a
6709 single bad template instantiation. */
6710 if (complain & tf_error
6711 && (last_loc.line != input_line
6712 || last_loc.file != input_filename))
6714 if (TREE_CODE (type) == VOID_TYPE)
6715 error ("forming reference to void");
6717 error ("forming %s to reference type `%T'",
6718 (code == POINTER_TYPE) ? "pointer" : "reference",
6720 last_loc = input_location;
6723 return error_mark_node;
6725 else if (code == POINTER_TYPE)
6727 r = build_pointer_type (type);
6728 if (TREE_CODE (type) == METHOD_TYPE)
6729 r = build_ptrmemfunc_type (r);
6732 r = build_reference_type (type);
6733 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6735 if (r != error_mark_node)
6736 /* Will this ever be needed for TYPE_..._TO values? */
6743 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
6744 if (r == error_mark_node || !IS_AGGR_TYPE (r))
6748 Type deduction may fail for any of the following
6751 -- Attempting to create "pointer to member of T" when T
6752 is not a class type. */
6753 if (complain & tf_error)
6754 error ("creating pointer to member of non-class type `%T'", r);
6755 return error_mark_node;
6757 if (TREE_CODE (type) == REFERENCE_TYPE)
6759 if (complain & tf_error)
6760 error ("creating pointer to member reference type `%T'", type);
6762 return error_mark_node;
6764 my_friendly_assert (TREE_CODE (type) != METHOD_TYPE, 20011231);
6765 if (TREE_CODE (type) == FUNCTION_TYPE)
6767 /* This is really a method type. The cv qualifiers of the
6768 this pointer should _not_ be determined by the cv
6769 qualifiers of the class type. They should be held
6770 somewhere in the FUNCTION_TYPE, but we don't do that at
6771 the moment. Consider
6772 typedef void (Func) () const;
6774 template <typename T1> void Foo (Func T1::*);
6779 method_type = build_method_type_directly (TYPE_MAIN_VARIANT (r),
6781 TYPE_ARG_TYPES (type));
6782 return build_ptrmemfunc_type (build_pointer_type (method_type));
6785 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
6795 fntype = tsubst_function_type (t, args, complain, in_decl);
6796 if (fntype == error_mark_node)
6797 return error_mark_node;
6799 /* Substitute the exception specification. */
6800 raises = TYPE_RAISES_EXCEPTIONS (t);
6803 tree list = NULL_TREE;
6805 if (! TREE_VALUE (raises))
6808 for (; raises != NULL_TREE; raises = TREE_CHAIN (raises))
6810 tree spec = TREE_VALUE (raises);
6812 spec = tsubst (spec, args, complain, in_decl);
6813 if (spec == error_mark_node)
6815 list = add_exception_specifier (list, spec, complain);
6817 fntype = build_exception_variant (fntype, list);
6823 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
6824 if (domain == error_mark_node)
6825 return error_mark_node;
6827 /* As an optimization, we avoid regenerating the array type if
6828 it will obviously be the same as T. */
6829 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
6832 /* These checks should match the ones in grokdeclarator.
6836 The deduction may fail for any of the following reasons:
6838 -- Attempting to create an array with an element type that
6839 is void, a function type, or a reference type. */
6840 if (TREE_CODE (type) == VOID_TYPE
6841 || TREE_CODE (type) == FUNCTION_TYPE
6842 || TREE_CODE (type) == REFERENCE_TYPE)
6844 if (complain & tf_error)
6845 error ("creating array of `%T'", type);
6846 return error_mark_node;
6849 r = build_cplus_array_type (type, domain);
6856 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6857 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
6859 if (e1 == error_mark_node || e2 == error_mark_node)
6860 return error_mark_node;
6862 return fold (build (TREE_CODE (t), TREE_TYPE (t), e1, e2));
6868 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6869 if (e == error_mark_node)
6870 return error_mark_node;
6872 return fold (build (TREE_CODE (t), TREE_TYPE (t), e));
6877 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
6878 in_decl, /*entering_scope=*/1);
6879 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
6882 if (ctx == error_mark_node || f == error_mark_node)
6883 return error_mark_node;
6885 if (!IS_AGGR_TYPE (ctx))
6887 if (complain & tf_error)
6888 error ("`%T' is not a class, struct, or union type",
6890 return error_mark_node;
6892 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
6894 /* Normally, make_typename_type does not require that the CTX
6895 have complete type in order to allow things like:
6897 template <class T> struct S { typename S<T>::X Y; };
6899 But, such constructs have already been resolved by this
6900 point, so here CTX really should have complete type, unless
6901 it's a partial instantiation. */
6902 ctx = complete_type (ctx);
6903 if (!COMPLETE_TYPE_P (ctx))
6905 if (complain & tf_error)
6906 cxx_incomplete_type_error (NULL_TREE, ctx);
6907 return error_mark_node;
6911 f = make_typename_type (ctx, f,
6912 (complain & tf_error) | tf_keep_type_decl);
6913 if (f == error_mark_node)
6915 if (TREE_CODE (f) == TYPE_DECL)
6917 complain |= tf_ignore_bad_quals;
6921 return cp_build_qualified_type_real
6922 (f, cp_type_quals (f) | cp_type_quals (t), complain);
6925 case UNBOUND_CLASS_TEMPLATE:
6927 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
6928 in_decl, /*entering_scope=*/1);
6929 tree name = TYPE_IDENTIFIER (t);
6931 if (ctx == error_mark_node || name == error_mark_node)
6932 return error_mark_node;
6934 return make_unbound_class_template (ctx, name, complain);
6939 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6940 if (e == error_mark_node)
6941 return error_mark_node;
6942 return make_pointer_declarator (type, e);
6947 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6948 if (e == error_mark_node)
6949 return error_mark_node;
6950 return make_reference_declarator (type, e);
6955 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6956 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
6957 if (e1 == error_mark_node || e2 == error_mark_node)
6958 return error_mark_node;
6960 return build_nt (ARRAY_REF, e1, e2, tsubst_expr);
6965 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6966 tree e2 = (tsubst_call_declarator_parms
6967 (CALL_DECLARATOR_PARMS (t), args, complain, in_decl));
6968 tree e3 = tsubst (CALL_DECLARATOR_EXCEPTION_SPEC (t), args,
6971 if (e1 == error_mark_node || e2 == error_mark_node
6972 || e3 == error_mark_node)
6973 return error_mark_node;
6975 return make_call_declarator (e1, e2, CALL_DECLARATOR_QUALS (t), e3);
6980 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6981 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
6982 if (e1 == error_mark_node || e2 == error_mark_node)
6983 return error_mark_node;
6985 return build_nt (TREE_CODE (t), e1, e2);
6990 tree e1 = tsubst_expr (TYPE_FIELDS (t), args, complain, in_decl);
6991 if (e1 == error_mark_node)
6992 return error_mark_node;
6994 return cp_build_qualified_type_real (TREE_TYPE (e1),
6996 | cp_type_quals (TREE_TYPE (e1)),
7001 sorry ("use of `%s' in template",
7002 tree_code_name [(int) TREE_CODE (t)]);
7003 return error_mark_node;
7007 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7008 type of the expression on the left-hand side of the "." or "->"
7012 tsubst_baselink (tree baselink, tree object_type,
7013 tree args, tsubst_flags_t complain, tree in_decl)
7016 tree qualifying_scope;
7018 tree template_args = 0;
7019 bool template_id_p = false;
7021 /* A baselink indicates a function from a base class. The
7022 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7023 non-dependent types; otherwise, the lookup could not have
7024 succeeded. However, they may indicate bases of the template
7025 class, rather than the instantiated class.
7027 In addition, lookups that were not ambiguous before may be
7028 ambiguous now. Therefore, we perform the lookup again. */
7029 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7030 fns = BASELINK_FUNCTIONS (baselink);
7031 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7033 template_id_p = true;
7034 template_args = TREE_OPERAND (fns, 1);
7035 fns = TREE_OPERAND (fns, 0);
7037 template_args = tsubst_template_args (template_args, args,
7040 name = DECL_NAME (get_first_fn (fns));
7041 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7042 if (BASELINK_P (baselink) && template_id_p)
7043 BASELINK_FUNCTIONS (baselink)
7044 = build_nt (TEMPLATE_ID_EXPR,
7045 BASELINK_FUNCTIONS (baselink),
7048 object_type = current_class_type;
7049 return adjust_result_of_qualified_name_lookup (baselink,
7054 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7055 true if the qualified-id will be a postfix-expression in-and-of
7056 itself; false if more of the postfix-expression follows the
7057 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7061 tsubst_qualified_id (tree qualified_id, tree args,
7062 tsubst_flags_t complain, tree in_decl,
7063 bool done, bool address_p)
7071 my_friendly_assert (TREE_CODE (qualified_id) == SCOPE_REF, 20030706);
7073 /* Figure out what name to look up. */
7074 name = TREE_OPERAND (qualified_id, 1);
7075 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7078 template_args = TREE_OPERAND (name, 1);
7080 template_args = tsubst_template_args (template_args, args,
7082 name = TREE_OPERAND (name, 0);
7086 is_template = false;
7087 template_args = NULL_TREE;
7090 /* Substitute into the qualifying scope. When there are no ARGS, we
7091 are just trying to simplify a non-dependent expression. In that
7092 case the qualifying scope may be dependent, and, in any case,
7093 substituting will not help. */
7094 scope = TREE_OPERAND (qualified_id, 0);
7097 scope = tsubst (scope, args, complain, in_decl);
7098 expr = tsubst_copy (name, args, complain, in_decl);
7103 my_friendly_assert (!dependent_type_p (scope), 20030729);
7105 if (!BASELINK_P (name) && !DECL_P (expr))
7107 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7108 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7109 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7111 if (complain & tf_error)
7112 error ("`%E' names a type, but a non-type is expected",
7114 return error_mark_node;
7119 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7122 /* Remember that there was a reference to this entity. */
7126 if (!args && TREE_CODE (expr) == VAR_DECL)
7127 expr = DECL_INITIAL (expr);
7131 expr = lookup_template_function (expr, template_args);
7133 if (expr == error_mark_node && complain & tf_error)
7134 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1));
7135 else if (TYPE_P (scope))
7137 expr = (adjust_result_of_qualified_name_lookup
7138 (expr, scope, current_class_type));
7139 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7145 /* Like tsubst, but deals with expressions. This function just replaces
7146 template parms; to finish processing the resultant expression, use
7150 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7152 enum tree_code code;
7155 if (t == NULL_TREE || t == error_mark_node)
7158 code = TREE_CODE (t);
7163 r = retrieve_local_specialization (t);
7164 my_friendly_assert (r != NULL, 20020903);
7172 if (DECL_TEMPLATE_PARM_P (t))
7173 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7174 /* There is no need to substitute into namespace-scope
7176 if (DECL_NAMESPACE_SCOPE_P (t))
7179 /* Unfortunately, we cannot just call lookup_name here.
7182 template <int I> int f() {
7184 struct S { void g() { E e = a; } };
7187 When we instantiate f<7>::S::g(), say, lookup_name is not
7188 clever enough to find f<7>::a. */
7190 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7191 /*entering_scope=*/0);
7193 for (v = TYPE_VALUES (enum_type);
7196 if (TREE_PURPOSE (v) == DECL_NAME (t))
7197 return TREE_VALUE (v);
7199 /* We didn't find the name. That should never happen; if
7200 name-lookup found it during preliminary parsing, we
7201 should find it again here during instantiation. */
7207 if (DECL_CONTEXT (t))
7211 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7212 /*entering_scope=*/1);
7213 if (ctx != DECL_CONTEXT (t))
7214 return lookup_field (ctx, DECL_NAME (t), 0, false);
7220 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7221 || local_variable_p (t))
7222 t = tsubst (t, args, complain, in_decl);
7227 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7230 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7231 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7232 args, complain, in_decl);
7233 else if (is_member_template (t))
7234 return tsubst (t, args, complain, in_decl);
7235 else if (DECL_CLASS_SCOPE_P (t)
7236 && uses_template_parms (DECL_CONTEXT (t)))
7238 /* Template template argument like the following example need
7241 template <template <class> class TT> struct C {};
7242 template <class T> struct D {
7243 template <class U> struct E {};
7248 We are processing the template argument `E' in #1 for
7249 the template instantiation #2. Originally, `E' is a
7250 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7251 have to substitute this with one having context `D<int>'. */
7253 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7254 return lookup_field (context, DECL_NAME(t), 0, false);
7257 /* Ordinary template template argument. */
7261 case REINTERPRET_CAST_EXPR:
7262 case CONST_CAST_EXPR:
7263 case STATIC_CAST_EXPR:
7264 case DYNAMIC_CAST_EXPR:
7267 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7268 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7272 case TRUTH_NOT_EXPR:
7275 case CONVERT_EXPR: /* Unary + */
7284 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7285 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7292 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7293 name = TREE_OPERAND (t, 1);
7294 if (TREE_CODE (name) == BIT_NOT_EXPR)
7296 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7298 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7300 else if (TREE_CODE (name) == SCOPE_REF
7301 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7303 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7305 name = TREE_OPERAND (name, 1);
7306 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7308 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7309 name = build_nt (SCOPE_REF, base, name);
7311 else if (TREE_CODE (name) == BASELINK)
7312 name = tsubst_baselink (name,
7313 non_reference (TREE_TYPE (object)),
7317 name = tsubst_copy (name, args, complain, in_decl);
7318 return build_nt (COMPONENT_REF, object, name);
7324 case TRUNC_DIV_EXPR:
7326 case FLOOR_DIV_EXPR:
7327 case ROUND_DIV_EXPR:
7328 case EXACT_DIV_EXPR:
7332 case TRUNC_MOD_EXPR:
7333 case FLOOR_MOD_EXPR:
7334 case TRUTH_ANDIF_EXPR:
7335 case TRUTH_ORIF_EXPR:
7336 case TRUTH_AND_EXPR:
7355 case PREDECREMENT_EXPR:
7356 case PREINCREMENT_EXPR:
7357 case POSTDECREMENT_EXPR:
7358 case POSTINCREMENT_EXPR:
7360 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7361 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7364 return build_nt (code,
7365 tsubst_copy (TREE_OPERAND (t, 0), args,
7367 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7372 /* This processing should really occur in tsubst_expr. However,
7373 tsubst_expr does not recurse into expressions, since it
7374 assumes that there aren't any statements inside them. So, we
7375 need to expand the STMT_EXPR here. */
7376 if (!processing_template_decl)
7378 tree stmt_expr = begin_stmt_expr ();
7380 tsubst_expr (STMT_EXPR_STMT (t), args,
7381 complain | tf_stmt_expr_cmpd, in_decl);
7382 return finish_stmt_expr (stmt_expr, false);
7389 case PSEUDO_DTOR_EXPR:
7392 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7393 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7394 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
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));
7404 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7411 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7412 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7413 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7414 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7418 case TEMPLATE_ID_EXPR:
7420 /* Substituted template arguments */
7421 tree fn = TREE_OPERAND (t, 0);
7422 tree targs = TREE_OPERAND (t, 1);
7424 fn = tsubst_copy (fn, args, complain, in_decl);
7426 targs = tsubst_template_args (targs, args, complain, in_decl);
7428 return lookup_template_function (fn, targs);
7433 tree purpose, value, chain;
7435 if (t == void_list_node)
7438 purpose = TREE_PURPOSE (t);
7440 purpose = tsubst_copy (purpose, args, complain, in_decl);
7441 value = TREE_VALUE (t);
7443 value = tsubst_copy (value, args, complain, in_decl);
7444 chain = TREE_CHAIN (t);
7445 if (chain && chain != void_type_node)
7446 chain = tsubst_copy (chain, args, complain, in_decl);
7447 if (purpose == TREE_PURPOSE (t)
7448 && value == TREE_VALUE (t)
7449 && chain == TREE_CHAIN (t))
7451 return tree_cons (purpose, value, chain);
7458 case TEMPLATE_TYPE_PARM:
7459 case TEMPLATE_TEMPLATE_PARM:
7460 case BOUND_TEMPLATE_TEMPLATE_PARM:
7461 case TEMPLATE_PARM_INDEX:
7463 case REFERENCE_TYPE:
7469 case UNBOUND_CLASS_TEMPLATE:
7472 return tsubst (t, args, complain, in_decl);
7474 case IDENTIFIER_NODE:
7475 if (IDENTIFIER_TYPENAME_P (t))
7477 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7478 return mangle_conv_op_name_for_type (new_type);
7485 r = build_constructor
7486 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7487 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7488 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7493 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7495 tsubst (TREE_TYPE (t), args, complain, in_decl));
7502 /* Like tsubst_copy for expressions, etc. but also does semantic
7506 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7509 tsubst_flags_t stmt_expr
7510 = complain & (tf_stmt_expr_cmpd | tf_stmt_expr_body);
7512 complain ^= stmt_expr;
7513 if (t == NULL_TREE || t == error_mark_node)
7516 if (processing_template_decl)
7517 return tsubst_copy (t, args, complain, in_decl);
7519 if (!STATEMENT_CODE_P (TREE_CODE (t)))
7520 return tsubst_copy_and_build (t, args, complain, in_decl,
7521 /*function_p=*/false);
7523 switch (TREE_CODE (t))
7525 case CTOR_INITIALIZER:
7527 finish_mem_initializers (tsubst_initializer_list
7528 (TREE_OPERAND (t, 0), args));
7533 finish_return_stmt (tsubst_expr (RETURN_STMT_EXPR (t),
7534 args, complain, in_decl));
7543 r = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
7544 if (stmt_expr & tf_stmt_expr_body && !TREE_CHAIN (t))
7545 finish_stmt_expr_expr (r);
7547 finish_expr_stmt (r);
7553 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
7554 args, complain, in_decl));
7563 decl = DECL_STMT_DECL (t);
7564 if (TREE_CODE (decl) == LABEL_DECL)
7565 finish_label_decl (DECL_NAME (decl));
7566 else if (TREE_CODE (decl) == USING_DECL)
7568 tree scope = DECL_INITIAL (decl);
7569 tree name = DECL_NAME (decl);
7572 scope = tsubst_expr (scope, args, complain, in_decl);
7573 decl = lookup_qualified_name (scope, name,
7574 /*is_type_p=*/false,
7575 /*complain=*/false);
7576 if (decl == error_mark_node)
7577 qualified_name_lookup_error (scope, name);
7579 do_local_using_decl (decl);
7583 init = DECL_INITIAL (decl);
7584 decl = tsubst (decl, args, complain, in_decl);
7585 if (decl != error_mark_node)
7588 DECL_INITIAL (decl) = error_mark_node;
7589 /* By marking the declaration as instantiated, we avoid
7590 trying to instantiate it. Since instantiate_decl can't
7591 handle local variables, and since we've already done
7592 all that needs to be done, that's the right thing to
7594 if (TREE_CODE (decl) == VAR_DECL)
7595 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7596 if (TREE_CODE (decl) == VAR_DECL
7597 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
7598 /* Anonymous aggregates are a special case. */
7599 finish_anon_union (decl);
7602 maybe_push_decl (decl);
7603 if (TREE_CODE (decl) == VAR_DECL
7604 && DECL_PRETTY_FUNCTION_P (decl))
7606 /* For __PRETTY_FUNCTION__ we have to adjust the
7608 const char *const name
7609 = cxx_printable_name (current_function_decl, 2);
7610 init = cp_fname_init (name);
7611 TREE_TYPE (decl) = TREE_TYPE (init);
7614 init = tsubst_expr (init, args, complain, in_decl);
7615 cp_finish_decl (decl, init, NULL_TREE, 0);
7620 /* A DECL_STMT can also be used as an expression, in the condition
7621 clause of an if/for/while construct. If we aren't followed by
7622 another statement, return our decl. */
7623 if (TREE_CHAIN (t) == NULL_TREE)
7632 stmt = begin_for_stmt ();
7633 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
7634 finish_for_init_stmt (stmt);
7635 finish_for_cond (tsubst_expr (FOR_COND (t),
7636 args, complain, in_decl),
7638 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
7639 finish_for_expr (tmp, stmt);
7640 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
7641 finish_for_stmt (stmt);
7648 stmt = begin_while_stmt ();
7649 finish_while_stmt_cond (tsubst_expr (WHILE_COND (t),
7650 args, complain, in_decl),
7652 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
7653 finish_while_stmt (stmt);
7660 stmt = begin_do_stmt ();
7661 tsubst_expr (DO_BODY (t), args, complain, in_decl);
7662 finish_do_body (stmt);
7663 finish_do_stmt (tsubst_expr (DO_COND (t),
7664 args, complain, in_decl),
7672 stmt = begin_if_stmt ();
7673 finish_if_stmt_cond (tsubst_expr (IF_COND (t),
7674 args, complain, in_decl),
7677 if (tmp = THEN_CLAUSE (t), tmp)
7679 tsubst_expr (tmp, args, complain, in_decl);
7680 finish_then_clause (stmt);
7683 if (tmp = ELSE_CLAUSE (t), tmp)
7685 begin_else_clause ();
7686 tsubst_expr (tmp, args, complain, in_decl);
7687 finish_else_clause (stmt);
7697 if (COMPOUND_STMT_BODY_BLOCK (t))
7698 stmt = begin_function_body ();
7700 stmt = begin_compound_stmt (COMPOUND_STMT_NO_SCOPE (t));
7702 tsubst_expr (COMPOUND_BODY (t), args,
7703 complain | ((stmt_expr & tf_stmt_expr_cmpd) << 1),
7706 if (COMPOUND_STMT_BODY_BLOCK (t))
7707 finish_function_body (stmt);
7709 finish_compound_stmt (stmt);
7715 finish_break_stmt ();
7720 finish_continue_stmt ();
7728 stmt = begin_switch_stmt ();
7729 val = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
7730 finish_switch_cond (val, stmt);
7731 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
7732 finish_switch_stmt (stmt);
7738 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
7739 tsubst_expr (CASE_HIGH (t), args, complain,
7744 input_line = STMT_LINENO (t);
7745 finish_label_stmt (DECL_NAME (LABEL_STMT_LABEL (t)));
7749 input_filename = FILE_STMT_FILENAME (t);
7750 add_stmt (build_nt (FILE_STMT, FILE_STMT_FILENAME_NODE (t)));
7755 tmp = GOTO_DESTINATION (t);
7756 if (TREE_CODE (tmp) != LABEL_DECL)
7757 /* Computed goto's must be tsubst'd into. On the other hand,
7758 non-computed gotos must not be; the identifier in question
7759 will have no binding. */
7760 tmp = tsubst_expr (tmp, args, complain, in_decl);
7762 tmp = DECL_NAME (tmp);
7763 finish_goto_stmt (tmp);
7768 tmp = finish_asm_stmt
7770 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
7771 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
7772 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
7773 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
7774 ASM_INPUT_P (tmp) = ASM_INPUT_P (t);
7781 stmt = begin_try_block ();
7782 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7783 finish_cleanup_try_block (stmt);
7784 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
7790 if (FN_TRY_BLOCK_P (t))
7791 stmt = begin_function_try_block ();
7793 stmt = begin_try_block ();
7795 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7797 if (FN_TRY_BLOCK_P (t))
7798 finish_function_try_block (stmt);
7800 finish_try_block (stmt);
7802 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
7803 if (FN_TRY_BLOCK_P (t))
7804 finish_function_handler_sequence (stmt);
7806 finish_handler_sequence (stmt);
7815 stmt = begin_handler ();
7816 if (HANDLER_PARMS (t))
7818 decl = DECL_STMT_DECL (HANDLER_PARMS (t));
7819 decl = tsubst (decl, args, complain, in_decl);
7820 /* Prevent instantiate_decl from trying to instantiate
7821 this variable. We've already done all that needs to be
7823 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7827 finish_handler_parms (decl, stmt);
7828 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
7829 finish_handler (stmt);
7835 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
7842 return tsubst_expr (TREE_CHAIN (t), args, complain | stmt_expr, in_decl);
7845 /* T is a postfix-expression that is not being used in a function
7846 call. Return the substituted version of T. */
7849 tsubst_non_call_postfix_expression (tree t, tree args,
7850 tsubst_flags_t complain,
7853 if (TREE_CODE (t) == SCOPE_REF)
7854 t = tsubst_qualified_id (t, args, complain, in_decl,
7855 /*done=*/false, /*address_p=*/false);
7857 t = tsubst_copy_and_build (t, args, complain, in_decl,
7858 /*function_p=*/false);
7863 /* Like tsubst but deals with expressions and performs semantic
7864 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
7867 tsubst_copy_and_build (tree t,
7869 tsubst_flags_t complain,
7873 #define RECUR(NODE) \
7874 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
7878 if (t == NULL_TREE || t == error_mark_node)
7881 switch (TREE_CODE (t))
7886 case IDENTIFIER_NODE:
7890 tree qualifying_class;
7891 bool non_constant_expression_p;
7892 const char *error_msg;
7894 if (IDENTIFIER_TYPENAME_P (t))
7896 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7897 t = mangle_conv_op_name_for_type (new_type);
7900 /* Look up the name. */
7901 decl = lookup_name (t, 0);
7903 /* By convention, expressions use ERROR_MARK_NODE to indicate
7904 failure, not NULL_TREE. */
7905 if (decl == NULL_TREE)
7906 decl = error_mark_node;
7908 decl = finish_id_expression (t, decl, NULL_TREE,
7911 /*constant_expression_p=*/false,
7912 /*allow_non_constant_expression_p=*/false,
7913 &non_constant_expression_p,
7917 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
7918 decl = unqualified_name_lookup_error (decl);
7922 case TEMPLATE_ID_EXPR:
7925 tree template = RECUR (TREE_OPERAND (t, 0));
7926 tree targs = TREE_OPERAND (t, 1);
7929 targs = tsubst_template_args (targs, args, complain, in_decl);
7931 if (TREE_CODE (template) == COMPONENT_REF)
7933 object = TREE_OPERAND (template, 0);
7934 template = TREE_OPERAND (template, 1);
7938 template = lookup_template_function (template, targs);
7941 return build (COMPONENT_REF, TREE_TYPE (template),
7948 return build_x_indirect_ref (RECUR (TREE_OPERAND (t, 0)), "unary *");
7951 return build_functional_cast
7952 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7953 RECUR (TREE_OPERAND (t, 0)));
7955 case REINTERPRET_CAST_EXPR:
7956 return build_reinterpret_cast
7957 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7958 RECUR (TREE_OPERAND (t, 0)));
7960 case CONST_CAST_EXPR:
7961 return build_const_cast
7962 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7963 RECUR (TREE_OPERAND (t, 0)));
7965 case DYNAMIC_CAST_EXPR:
7966 return build_dynamic_cast
7967 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7968 RECUR (TREE_OPERAND (t, 0)));
7970 case STATIC_CAST_EXPR:
7971 return build_static_cast
7972 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7973 RECUR (TREE_OPERAND (t, 0)));
7975 case POSTDECREMENT_EXPR:
7976 case POSTINCREMENT_EXPR:
7977 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
7978 args, complain, in_decl);
7979 return build_x_unary_op (TREE_CODE (t), op1);
7981 case PREDECREMENT_EXPR:
7982 case PREINCREMENT_EXPR:
7986 case TRUTH_NOT_EXPR:
7987 case CONVERT_EXPR: /* Unary + */
7990 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
7993 op1 = TREE_OPERAND (t, 0);
7994 if (TREE_CODE (op1) == SCOPE_REF)
7995 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
7996 /*done=*/true, /*address_p=*/true);
7998 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8000 if (TREE_CODE (op1) == LABEL_DECL)
8001 return finish_label_address_expr (DECL_NAME (op1));
8002 return build_x_unary_op (ADDR_EXPR, op1);
8007 case TRUNC_DIV_EXPR:
8009 case FLOOR_DIV_EXPR:
8010 case ROUND_DIV_EXPR:
8011 case EXACT_DIV_EXPR:
8015 case TRUNC_MOD_EXPR:
8016 case FLOOR_MOD_EXPR:
8017 case TRUTH_ANDIF_EXPR:
8018 case TRUTH_ORIF_EXPR:
8019 case TRUTH_AND_EXPR:
8035 return build_x_binary_op
8037 RECUR (TREE_OPERAND (t, 0)),
8038 RECUR (TREE_OPERAND (t, 1)));
8041 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8042 /*address_p=*/false);
8045 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8048 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)));
8050 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8051 args, complain, in_decl);
8052 /* Remember that there was a reference to this entity. */
8055 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8059 op1 = TREE_OPERAND (t, 0);
8062 /* When there are no ARGS, we are trying to evaluate a
8063 non-dependent expression from the parser. Trying to do
8064 the substitutions may not work. */
8066 op1 = TREE_TYPE (op1);
8075 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8077 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8080 return build_x_modify_expr
8081 (RECUR (TREE_OPERAND (t, 0)),
8082 TREE_CODE (TREE_OPERAND (t, 1)),
8083 RECUR (TREE_OPERAND (t, 2)));
8086 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8087 args, complain, in_decl);
8088 /* Remember that there was a reference to this entity. */
8091 return build_x_arrow (op1);
8095 (RECUR (TREE_OPERAND (t, 0)),
8096 RECUR (TREE_OPERAND (t, 1)),
8097 RECUR (TREE_OPERAND (t, 2)),
8098 NEW_EXPR_USE_GLOBAL (t));
8101 return delete_sanity
8102 (RECUR (TREE_OPERAND (t, 0)),
8103 RECUR (TREE_OPERAND (t, 1)),
8104 DELETE_EXPR_USE_VEC (t),
8105 DELETE_EXPR_USE_GLOBAL (t));
8108 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8109 RECUR (TREE_OPERAND (t, 1)));
8118 function = TREE_OPERAND (t, 0);
8119 /* When we parsed the expression, we determined whether or
8120 not Koenig lookup should be performed. */
8121 koenig_p = KOENIG_LOOKUP_P (t);
8122 if (TREE_CODE (function) == SCOPE_REF)
8125 function = tsubst_qualified_id (function, args, complain, in_decl,
8127 /*address_p=*/false);
8131 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8132 && (TREE_CODE (TREE_OPERAND (function, 1))
8134 function = tsubst_copy_and_build (function, args, complain,
8137 if (BASELINK_P (function))
8141 call_args = RECUR (TREE_OPERAND (t, 1));
8144 && (is_overloaded_fn (function)
8145 || DECL_P (function)
8146 || TREE_CODE (function) == IDENTIFIER_NODE))
8147 function = perform_koenig_lookup (function, call_args);
8149 if (TREE_CODE (function) == IDENTIFIER_NODE)
8151 unqualified_name_lookup_error (function);
8152 return error_mark_node;
8155 /* Remember that there was a reference to this entity. */
8156 if (DECL_P (function))
8157 mark_used (function);
8159 function = convert_from_reference (function);
8161 if (TREE_CODE (function) == OFFSET_REF)
8162 return build_offset_ref_call_from_tree (function, call_args);
8163 if (TREE_CODE (function) == COMPONENT_REF)
8164 return (build_new_method_call
8165 (TREE_OPERAND (function, 0),
8166 TREE_OPERAND (function, 1),
8167 call_args, NULL_TREE,
8168 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8169 return finish_call_expr (function, call_args,
8170 /*disallow_virtual=*/qualified_p,
8175 return build_x_conditional_expr
8176 (RECUR (TREE_OPERAND (t, 0)),
8177 RECUR (TREE_OPERAND (t, 1)),
8178 RECUR (TREE_OPERAND (t, 2)));
8180 case PSEUDO_DTOR_EXPR:
8181 return finish_pseudo_destructor_expr
8182 (RECUR (TREE_OPERAND (t, 0)),
8183 RECUR (TREE_OPERAND (t, 1)),
8184 RECUR (TREE_OPERAND (t, 2)));
8188 tree purpose, value, chain;
8190 if (t == void_list_node)
8193 purpose = TREE_PURPOSE (t);
8195 purpose = RECUR (purpose);
8196 value = TREE_VALUE (t);
8198 value = RECUR (value);
8199 chain = TREE_CHAIN (t);
8200 if (chain && chain != void_type_node)
8201 chain = RECUR (chain);
8202 if (purpose == TREE_PURPOSE (t)
8203 && value == TREE_VALUE (t)
8204 && chain == TREE_CHAIN (t))
8206 return tree_cons (purpose, value, chain);
8214 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8215 args, complain, in_decl);
8216 /* Remember that there was a reference to this entity. */
8217 if (DECL_P (object))
8220 member = TREE_OPERAND (t, 1);
8221 if (BASELINK_P (member))
8222 member = tsubst_baselink (member,
8223 non_reference (TREE_TYPE (object)),
8224 args, complain, in_decl);
8226 member = tsubst_copy (member, args, complain, in_decl);
8228 if (!CLASS_TYPE_P (TREE_TYPE (object)))
8230 if (TREE_CODE (member) == BIT_NOT_EXPR)
8231 return finish_pseudo_destructor_expr (object,
8233 TREE_TYPE (object));
8234 else if (TREE_CODE (member) == SCOPE_REF
8235 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8236 return finish_pseudo_destructor_expr (object,
8238 TREE_TYPE (object));
8240 else if (TREE_CODE (member) == SCOPE_REF
8241 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8246 /* Lookup the template functions now that we know what the
8248 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8249 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8250 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8251 /*is_type_p=*/false,
8252 /*complain=*/false);
8253 if (BASELINK_P (member))
8254 BASELINK_FUNCTIONS (member)
8255 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8259 qualified_name_lookup_error (TREE_TYPE (object), tmpl);
8260 return error_mark_node;
8263 else if (TREE_CODE (member) == FIELD_DECL)
8264 return finish_non_static_data_member (member, object, NULL_TREE);
8266 return finish_class_member_access_expr (object, member);
8271 (RECUR (TREE_OPERAND (t, 0)));
8277 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8280 /* digest_init will do the wrong thing if we let it. */
8281 if (type && TYPE_PTRMEMFUNC_P (type))
8285 /* We do not want to process the purpose of aggregate
8286 initializers as they are identifier nodes which will be
8287 looked up by digest_init. */
8288 purpose_p = !(type && IS_AGGR_TYPE (type));
8289 for (elts = CONSTRUCTOR_ELTS (t);
8291 elts = TREE_CHAIN (elts))
8293 tree purpose = TREE_PURPOSE (elts);
8294 tree value = TREE_VALUE (elts);
8296 if (purpose && purpose_p)
8297 purpose = RECUR (purpose);
8298 value = RECUR (value);
8299 r = tree_cons (purpose, value, r);
8302 r = build_constructor (NULL_TREE, nreverse (r));
8303 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8306 return digest_init (type, r, 0);
8312 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8313 if (TYPE_P (operand_0))
8314 return get_typeid (operand_0);
8315 return build_typeid (operand_0);
8319 return convert_from_reference (tsubst_copy (t, args, complain, in_decl));
8323 t = tsubst_copy (t, args, complain, in_decl);
8325 /* If there are no ARGS, then we are evaluating a
8326 non-dependent expression. If the expression is
8327 non-dependent, the variable must be a constant. */
8328 t = DECL_INITIAL (t);
8329 return convert_from_reference (t);
8332 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8333 tsubst_copy (TREE_TYPE (t), args, complain,
8337 return tsubst_copy (t, args, complain, in_decl);
8343 /* Verify that the instantiated ARGS are valid. For type arguments,
8344 make sure that the type's linkage is ok. For non-type arguments,
8345 make sure they are constants if they are integral or enumerations.
8346 Emit an error under control of COMPLAIN, and return TRUE on error. */
8349 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8351 int ix, len = DECL_NTPARMS (tmpl);
8352 bool result = false;
8354 for (ix = 0; ix != len; ix++)
8356 tree t = TREE_VEC_ELT (args, ix);
8360 /* [basic.link]: A name with no linkage (notably, the name
8361 of a class or enumeration declared in a local scope)
8362 shall not be used to declare an entity with linkage.
8363 This implies that names with no linkage cannot be used as
8364 template arguments. */
8365 tree nt = no_linkage_check (t);
8369 if (!(complain & tf_error))
8371 else if (TYPE_ANONYMOUS_P (nt))
8372 error ("`%T' uses anonymous type", t);
8374 error ("`%T' uses local type `%T'", t, nt);
8377 /* In order to avoid all sorts of complications, we do not
8378 allow variably-modified types as template arguments. */
8379 else if (variably_modified_type_p (t))
8381 if (complain & tf_error)
8382 error ("`%T' is a variably modified type", t);
8386 /* A non-type argument of integral or enumerated type must be a
8388 else if (TREE_TYPE (t)
8389 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8390 && !TREE_CONSTANT (t))
8392 if (complain & tf_error)
8393 error ("integral expression `%E' is not constant", t);
8397 if (result && complain & tf_error)
8398 error (" trying to instantiate `%D'", tmpl);
8402 /* Instantiate the indicated variable or function template TMPL with
8403 the template arguments in TARG_PTR. */
8406 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8412 if (tmpl == error_mark_node)
8413 return error_mark_node;
8415 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 283);
8417 /* If this function is a clone, handle it specially. */
8418 if (DECL_CLONED_FUNCTION_P (tmpl))
8420 tree spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8424 /* Look for the clone. */
8425 for (clone = TREE_CHAIN (spec);
8426 clone && DECL_CLONED_FUNCTION_P (clone);
8427 clone = TREE_CHAIN (clone))
8428 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8430 /* We should always have found the clone by now. */
8435 /* Check to see if we already have this specialization. */
8436 spec = retrieve_specialization (tmpl, targ_ptr);
8437 if (spec != NULL_TREE)
8440 gen_tmpl = most_general_template (tmpl);
8441 if (tmpl != gen_tmpl)
8443 /* The TMPL is a partial instantiation. To get a full set of
8444 arguments we must add the arguments used to perform the
8445 partial instantiation. */
8446 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
8449 /* Check to see if we already have this specialization. */
8450 spec = retrieve_specialization (gen_tmpl, targ_ptr);
8451 if (spec != NULL_TREE)
8455 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
8457 return error_mark_node;
8459 /* We are building a FUNCTION_DECL, during which the access of its
8460 parameters and return types have to be checked. However this
8461 FUNCTION_DECL which is the desired context for access checking
8462 is not built yet. We solve this chicken-and-egg problem by
8463 deferring all checks until we have the FUNCTION_DECL. */
8464 push_deferring_access_checks (dk_deferred);
8466 /* substitute template parameters */
8467 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
8468 targ_ptr, complain, gen_tmpl);
8470 /* Now we know the specialization, compute access previously
8472 push_access_scope (fndecl);
8473 perform_deferred_access_checks ();
8474 pop_access_scope (fndecl);
8475 pop_deferring_access_checks ();
8477 /* The DECL_TI_TEMPLATE should always be the immediate parent
8478 template, not the most general template. */
8479 DECL_TI_TEMPLATE (fndecl) = tmpl;
8481 if (flag_external_templates)
8482 add_pending_template (fndecl);
8484 /* If we've just instantiated the main entry point for a function,
8485 instantiate all the alternate entry points as well. We do this
8486 by cloning the instantiation of the main entry point, not by
8487 instantiating the template clones. */
8488 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
8489 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
8494 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8495 arguments that are being used when calling it. TARGS is a vector
8496 into which the deduced template arguments are placed.
8498 Return zero for success, 2 for an incomplete match that doesn't resolve
8499 all the types, and 1 for complete failure. An error message will be
8500 printed only for an incomplete match.
8502 If FN is a conversion operator, or we are trying to produce a specific
8503 specialization, RETURN_TYPE is the return type desired.
8505 The EXPLICIT_TARGS are explicit template arguments provided via a
8508 The parameter STRICT is one of:
8511 We are deducing arguments for a function call, as in
8515 We are deducing arguments for a conversion function, as in
8519 We are deducing arguments when doing an explicit instantiation
8520 as in [temp.explicit], when determining an explicit specialization
8521 as in [temp.expl.spec], or when taking the address of a function
8522 template, as in [temp.deduct.funcaddr].
8525 We are deducing arguments when calculating the partial
8526 ordering between specializations of function or class
8527 templates, as in [temp.func.order] and [temp.class.order].
8529 LEN is the number of parms to consider before returning success, or -1
8530 for all. This is used in partial ordering to avoid comparing parms for
8531 which no actual argument was passed, since they are not considered in
8532 overload resolution (and are explicitly excluded from consideration in
8533 partial ordering in [temp.func.order]/6). */
8536 fn_type_unification (tree fn,
8537 tree explicit_targs,
8541 unification_kind_t strict,
8548 my_friendly_assert (TREE_CODE (fn) == TEMPLATE_DECL, 0);
8550 fntype = TREE_TYPE (fn);
8555 The specified template arguments must match the template
8556 parameters in kind (i.e., type, nontype, template), and there
8557 must not be more arguments than there are parameters;
8558 otherwise type deduction fails.
8560 Nontype arguments must match the types of the corresponding
8561 nontype template parameters, or must be convertible to the
8562 types of the corresponding nontype parameters as specified in
8563 _temp.arg.nontype_, otherwise type deduction fails.
8565 All references in the function type of the function template
8566 to the corresponding template parameters are replaced by the
8567 specified template argument values. If a substitution in a
8568 template parameter or in the function type of the function
8569 template results in an invalid type, type deduction fails. */
8571 tree converted_args;
8575 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8576 explicit_targs, NULL_TREE, tf_none,
8577 /*require_all_arguments=*/0));
8578 if (converted_args == error_mark_node)
8581 /* Substitute the explicit args into the function type. This is
8582 necessary so that, for instance, explicitly declared function
8583 arguments can match null pointed constants. If we were given
8584 an incomplete set of explicit args, we must not do semantic
8585 processing during substitution as we could create partial
8587 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
8588 processing_template_decl += incomplete;
8589 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
8590 processing_template_decl -= incomplete;
8592 if (fntype == error_mark_node)
8595 /* Place the explicitly specified arguments in TARGS. */
8596 for (i = NUM_TMPL_ARGS (converted_args); i--;)
8597 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
8600 parms = TYPE_ARG_TYPES (fntype);
8601 /* Never do unification on the 'this' parameter. */
8602 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
8603 parms = TREE_CHAIN (parms);
8607 /* We've been given a return type to match, prepend it. */
8608 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
8609 args = tree_cons (NULL_TREE, return_type, args);
8614 /* We allow incomplete unification without an error message here
8615 because the standard doesn't seem to explicitly prohibit it. Our
8616 callers must be ready to deal with unification failures in any
8618 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8619 targs, parms, args, /*subr=*/0,
8620 strict, /*allow_incomplete*/1, len);
8623 /* All is well so far. Now, check:
8627 When all template arguments have been deduced, all uses of
8628 template parameters in nondeduced contexts are replaced with
8629 the corresponding deduced argument values. If the
8630 substitution results in an invalid type, as described above,
8631 type deduction fails. */
8632 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
8639 /* Adjust types before performing type deduction, as described in
8640 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
8641 sections are symmetric. PARM is the type of a function parameter
8642 or the return type of the conversion function. ARG is the type of
8643 the argument passed to the call, or the type of the value
8644 initialized with the result of the conversion function. */
8647 maybe_adjust_types_for_deduction (unification_kind_t strict,
8660 /* Swap PARM and ARG throughout the remainder of this
8661 function; the handling is precisely symmetric since PARM
8662 will initialize ARG rather than vice versa. */
8670 /* There is nothing to do in this case. */
8674 /* DR 214. [temp.func.order] is underspecified, and leads to no
8675 ordering between things like `T *' and `T const &' for `U *'.
8676 The former has T=U and the latter T=U*. The former looks more
8677 specialized and John Spicer considers it well-formed (the EDG
8678 compiler accepts it).
8680 John also confirms that deduction should proceed as in a function
8681 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
8682 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
8683 to an actual call can have such a type.
8685 If both ARG and PARM are REFERENCE_TYPE, we change neither.
8686 If only ARG is a REFERENCE_TYPE, we look through that and then
8687 proceed as with DEDUCE_CALL (which could further convert it). */
8688 if (TREE_CODE (*arg) == REFERENCE_TYPE)
8690 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8692 *arg = TREE_TYPE (*arg);
8699 if (TREE_CODE (*parm) != REFERENCE_TYPE)
8701 /* [temp.deduct.call]
8703 If P is not a reference type:
8705 --If A is an array type, the pointer type produced by the
8706 array-to-pointer standard conversion (_conv.array_) is
8707 used in place of A for type deduction; otherwise,
8709 --If A is a function type, the pointer type produced by
8710 the function-to-pointer standard conversion
8711 (_conv.func_) is used in place of A for type deduction;
8714 --If A is a cv-qualified type, the top level
8715 cv-qualifiers of A's type are ignored for type
8717 if (TREE_CODE (*arg) == ARRAY_TYPE)
8718 *arg = build_pointer_type (TREE_TYPE (*arg));
8719 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
8720 *arg = build_pointer_type (*arg);
8722 *arg = TYPE_MAIN_VARIANT (*arg);
8725 /* [temp.deduct.call]
8727 If P is a cv-qualified type, the top level cv-qualifiers
8728 of P's type are ignored for type deduction. If P is a
8729 reference type, the type referred to by P is used for
8731 *parm = TYPE_MAIN_VARIANT (*parm);
8732 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8734 *parm = TREE_TYPE (*parm);
8735 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
8738 /* DR 322. For conversion deduction, remove a reference type on parm
8739 too (which has been swapped into ARG). */
8740 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
8741 *arg = TREE_TYPE (*arg);
8746 /* Most parms like fn_type_unification.
8748 If SUBR is 1, we're being called recursively (to unify the
8749 arguments of a function or method parameter of a function
8753 type_unification_real (tree tparms,
8758 unification_kind_t strict,
8759 int allow_incomplete,
8764 int ntparms = TREE_VEC_LENGTH (tparms);
8766 int saw_undeduced = 0;
8770 my_friendly_assert (TREE_CODE (tparms) == TREE_VEC, 289);
8771 my_friendly_assert (xparms == NULL_TREE
8772 || TREE_CODE (xparms) == TREE_LIST, 290);
8773 my_friendly_assert (!xargs || TREE_CODE (xargs) == TREE_LIST, 291);
8774 my_friendly_assert (ntparms > 0, 292);
8779 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
8780 | UNIFY_ALLOW_DERIVED);
8784 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
8788 sub_strict = UNIFY_ALLOW_NONE;
8792 sub_strict = UNIFY_ALLOW_NONE;
8808 && parms != void_list_node
8810 && args != void_list_node)
8812 parm = TREE_VALUE (parms);
8813 parms = TREE_CHAIN (parms);
8814 arg = TREE_VALUE (args);
8815 args = TREE_CHAIN (args);
8817 if (arg == error_mark_node)
8819 if (arg == unknown_type_node)
8820 /* We can't deduce anything from this, but we might get all the
8821 template args from other function args. */
8824 /* Conversions will be performed on a function argument that
8825 corresponds with a function parameter that contains only
8826 non-deducible template parameters and explicitly specified
8827 template parameters. */
8828 if (! uses_template_parms (parm))
8833 type = TREE_TYPE (arg);
8840 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
8842 if (same_type_p (parm, type))
8846 /* It might work; we shouldn't check now, because we might
8847 get into infinite recursion. Overload resolution will
8856 my_friendly_assert (TREE_TYPE (arg) != NULL_TREE, 293);
8857 if (type_unknown_p (arg))
8859 /* [temp.deduct.type] A template-argument can be deduced from
8860 a pointer to function or pointer to member function
8861 argument if the set of overloaded functions does not
8862 contain function templates and at most one of a set of
8863 overloaded functions provides a unique match. */
8865 if (resolve_overloaded_unification
8866 (tparms, targs, parm, arg, strict, sub_strict)
8871 arg = TREE_TYPE (arg);
8872 if (arg == error_mark_node)
8877 int arg_strict = sub_strict;
8880 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
8882 if (unify (tparms, targs, parm, arg, arg_strict))
8886 /* Are we done with the interesting parms? */
8890 /* Fail if we've reached the end of the parm list, and more args
8891 are present, and the parm list isn't variadic. */
8892 if (args && args != void_list_node && parms == void_list_node)
8894 /* Fail if parms are left and they don't have default values. */
8896 && parms != void_list_node
8897 && TREE_PURPOSE (parms) == NULL_TREE)
8902 for (i = 0; i < ntparms; i++)
8903 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
8905 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
8907 /* If this is an undeduced nontype parameter that depends on
8908 a type parameter, try another pass; its type may have been
8909 deduced from a later argument than the one from which
8910 this parameter can be deduced. */
8911 if (TREE_CODE (tparm) == PARM_DECL
8912 && uses_template_parms (TREE_TYPE (tparm))
8913 && !saw_undeduced++)
8916 if (!allow_incomplete)
8917 error ("incomplete type unification");
8923 /* Subroutine of type_unification_real. Args are like the variables at the
8924 call site. ARG is an overloaded function (or template-id); we try
8925 deducing template args from each of the overloads, and if only one
8926 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
8929 resolve_overloaded_unification (tree tparms,
8933 unification_kind_t strict,
8936 tree tempargs = copy_node (targs);
8940 if (TREE_CODE (arg) == ADDR_EXPR)
8942 arg = TREE_OPERAND (arg, 0);
8948 if (TREE_CODE (arg) == COMPONENT_REF)
8949 /* Handle `&x' where `x' is some static or non-static member
8951 arg = TREE_OPERAND (arg, 1);
8953 if (TREE_CODE (arg) == OFFSET_REF)
8954 arg = TREE_OPERAND (arg, 1);
8956 /* Strip baselink information. */
8957 if (BASELINK_P (arg))
8958 arg = BASELINK_FUNCTIONS (arg);
8960 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
8962 /* If we got some explicit template args, we need to plug them into
8963 the affected templates before we try to unify, in case the
8964 explicit args will completely resolve the templates in question. */
8966 tree expl_subargs = TREE_OPERAND (arg, 1);
8967 arg = TREE_OPERAND (arg, 0);
8969 for (; arg; arg = OVL_NEXT (arg))
8971 tree fn = OVL_CURRENT (arg);
8974 if (TREE_CODE (fn) != TEMPLATE_DECL)
8977 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
8981 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
8982 good += try_one_overload (tparms, targs, tempargs, parm,
8983 elem, strict, sub_strict, addr_p);
8987 else if (TREE_CODE (arg) == OVERLOAD
8988 || TREE_CODE (arg) == FUNCTION_DECL)
8990 for (; arg; arg = OVL_NEXT (arg))
8991 good += try_one_overload (tparms, targs, tempargs, parm,
8992 TREE_TYPE (OVL_CURRENT (arg)),
8993 strict, sub_strict, addr_p);
8998 /* [temp.deduct.type] A template-argument can be deduced from a pointer
8999 to function or pointer to member function argument if the set of
9000 overloaded functions does not contain function templates and at most
9001 one of a set of overloaded functions provides a unique match.
9003 So if we found multiple possibilities, we return success but don't
9008 int i = TREE_VEC_LENGTH (targs);
9010 if (TREE_VEC_ELT (tempargs, i))
9011 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9019 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9020 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9021 different overloads deduce different arguments for a given parm.
9022 ADDR_P is true if the expression for which deduction is being
9023 performed was of the form "& fn" rather than simply "fn".
9025 Returns 1 on success. */
9028 try_one_overload (tree tparms,
9033 unification_kind_t strict,
9041 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9042 to function or pointer to member function argument if the set of
9043 overloaded functions does not contain function templates and at most
9044 one of a set of overloaded functions provides a unique match.
9046 So if this is a template, just return success. */
9048 if (uses_template_parms (arg))
9051 if (TREE_CODE (arg) == METHOD_TYPE)
9052 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9054 arg = build_pointer_type (arg);
9056 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9058 /* We don't copy orig_targs for this because if we have already deduced
9059 some template args from previous args, unify would complain when we
9060 try to deduce a template parameter for the same argument, even though
9061 there isn't really a conflict. */
9062 nargs = TREE_VEC_LENGTH (targs);
9063 tempargs = make_tree_vec (nargs);
9065 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9068 /* First make sure we didn't deduce anything that conflicts with
9069 explicitly specified args. */
9070 for (i = nargs; i--; )
9072 tree elt = TREE_VEC_ELT (tempargs, i);
9073 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9075 if (elt == NULL_TREE)
9077 else if (uses_template_parms (elt))
9079 /* Since we're unifying against ourselves, we will fill in template
9080 args used in the function parm list with our own template parms.
9082 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9085 else if (oldelt && ! template_args_equal (oldelt, elt))
9089 for (i = nargs; i--; )
9091 tree elt = TREE_VEC_ELT (tempargs, i);
9094 TREE_VEC_ELT (targs, i) = elt;
9100 /* Verify that nondeduce template argument agrees with the type
9101 obtained from argument deduction. Return nonzero if the
9106 struct A { typedef int X; };
9107 template <class T, class U> struct C {};
9108 template <class T> struct C<T, typename T::X> {};
9110 Then with the instantiation `C<A, int>', we can deduce that
9111 `T' is `A' but unify () does not check whether `typename T::X'
9112 is `int'. This function ensure that they agree.
9114 TARGS, PARMS are the same as the arguments of unify.
9115 ARGS contains template arguments from all levels. */
9118 verify_class_unification (tree targs, tree parms, tree args)
9120 parms = tsubst (parms, add_outermost_template_args (args, targs),
9121 tf_none, NULL_TREE);
9122 if (parms == error_mark_node)
9125 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9128 /* PARM is a template class (perhaps with unbound template
9129 parameters). ARG is a fully instantiated type. If ARG can be
9130 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9131 TARGS are as for unify. */
9134 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9138 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9139 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9140 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9143 /* We need to make a new template argument vector for the call to
9144 unify. If we used TARGS, we'd clutter it up with the result of
9145 the attempted unification, even if this class didn't work out.
9146 We also don't want to commit ourselves to all the unifications
9147 we've already done, since unification is supposed to be done on
9148 an argument-by-argument basis. In other words, consider the
9149 following pathological case:
9151 template <int I, int J, int K>
9154 template <int I, int J>
9155 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9157 template <int I, int J, int K>
9158 void f(S<I, J, K>, S<I, I, I>);
9167 Now, by the time we consider the unification involving `s2', we
9168 already know that we must have `f<0, 0, 0>'. But, even though
9169 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9170 because there are two ways to unify base classes of S<0, 1, 2>
9171 with S<I, I, I>. If we kept the already deduced knowledge, we
9172 would reject the possibility I=1. */
9173 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9175 /* If unification failed, we're done. */
9176 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9177 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9183 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
9184 have already discovered to be satisfactory. ARG_BINFO is the binfo
9185 for the base class of ARG that we are currently examining. */
9188 get_template_base_recursive (tree tparms,
9197 tree arg = BINFO_TYPE (arg_binfo);
9199 if (!(flags & GTB_IGNORE_TYPE))
9201 tree r = try_class_unification (tparms, targs,
9204 /* If there is more than one satisfactory baseclass, then:
9208 If they yield more than one possible deduced A, the type
9212 if (r && rval && !same_type_p (r, rval))
9213 return error_mark_node;
9218 binfos = BINFO_BASETYPES (arg_binfo);
9219 n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
9221 /* Process base types. */
9222 for (i = 0; i < n_baselinks; i++)
9224 tree base_binfo = TREE_VEC_ELT (binfos, i);
9227 /* Skip this base, if we've already seen it. */
9228 if (BINFO_MARKED (base_binfo))
9232 (flags & GTB_VIA_VIRTUAL) || TREE_VIA_VIRTUAL (base_binfo);
9234 /* When searching for a non-virtual, we cannot mark virtually
9237 BINFO_MARKED (base_binfo) = 1;
9239 rval = get_template_base_recursive (tparms, targs,
9243 GTB_VIA_VIRTUAL * this_virtual);
9245 /* If we discovered more than one matching base class, we can
9247 if (rval == error_mark_node)
9248 return error_mark_node;
9254 /* Given a template type PARM and a class type ARG, find the unique
9255 base type in ARG that is an instance of PARM. We do not examine
9256 ARG itself; only its base-classes. If there is no appropriate base
9257 class, return NULL_TREE. If there is more than one, return
9258 error_mark_node. PARM may be the type of a partial specialization,
9259 as well as a plain template type. Used by unify. */
9262 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9267 my_friendly_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)), 92);
9269 arg_binfo = TYPE_BINFO (complete_type (arg));
9270 rval = get_template_base_recursive (tparms, targs,
9275 /* Since get_template_base_recursive marks the bases classes, we
9276 must unmark them here. */
9277 dfs_walk (arg_binfo, dfs_unmark, markedp, 0);
9282 /* Returns the level of DECL, which declares a template parameter. */
9285 template_decl_level (tree decl)
9287 switch (TREE_CODE (decl))
9291 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9294 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9302 /* Decide whether ARG can be unified with PARM, considering only the
9303 cv-qualifiers of each type, given STRICT as documented for unify.
9304 Returns nonzero iff the unification is OK on that basis.*/
9307 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9309 int arg_quals = cp_type_quals (arg);
9310 int parm_quals = cp_type_quals (parm);
9312 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM)
9314 /* If the cvr quals of parm will not unify with ARG, they'll be
9315 ignored in instantiation, so we have to do the same here. */
9316 if (TREE_CODE (arg) == REFERENCE_TYPE)
9317 parm_quals &= ~(TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE);
9318 if (!POINTER_TYPE_P (arg) &&
9319 TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9320 parm_quals &= ~TYPE_QUAL_RESTRICT;
9323 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9324 && (arg_quals & parm_quals) != parm_quals)
9327 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9328 && (parm_quals & arg_quals) != arg_quals)
9334 /* Takes parameters as for type_unification. Returns 0 if the
9335 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9336 bitwise or of the following flags:
9339 Require an exact match between PARM and ARG.
9340 UNIFY_ALLOW_MORE_CV_QUAL:
9341 Allow the deduced ARG to be more cv-qualified (by qualification
9342 conversion) than ARG.
9343 UNIFY_ALLOW_LESS_CV_QUAL:
9344 Allow the deduced ARG to be less cv-qualified than ARG.
9345 UNIFY_ALLOW_DERIVED:
9346 Allow the deduced ARG to be a template base class of ARG,
9347 or a pointer to a template base class of the type pointed to by
9349 UNIFY_ALLOW_INTEGER:
9350 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9351 case for more information.
9352 UNIFY_ALLOW_OUTER_LEVEL:
9353 This is the outermost level of a deduction. Used to determine validity
9354 of qualification conversions. A valid qualification conversion must
9355 have const qualified pointers leading up to the inner type which
9356 requires additional CV quals, except at the outer level, where const
9357 is not required [conv.qual]. It would be normal to set this flag in
9358 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9359 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9360 This is the outermost level of a deduction, and PARM can be more CV
9361 qualified at this point.
9362 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9363 This is the outermost level of a deduction, and PARM can be less CV
9364 qualified at this point.
9365 UNIFY_ALLOW_MAX_CORRECTION:
9366 This is an INTEGER_TYPE's maximum value. Used if the range may
9367 have been derived from a size specification, such as an array size.
9368 If the size was given by a nontype template parameter N, the maximum
9369 value will have the form N-1. The flag says that we can (and indeed
9370 must) unify N with (ARG + 1), an exception to the normal rules on
9374 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9379 int strict_in = strict;
9381 /* I don't think this will do the right thing with respect to types.
9382 But the only case I've seen it in so far has been array bounds, where
9383 signedness is the only information lost, and I think that will be
9385 while (TREE_CODE (parm) == NOP_EXPR)
9386 parm = TREE_OPERAND (parm, 0);
9388 if (arg == error_mark_node)
9390 if (arg == unknown_type_node)
9391 /* We can't deduce anything from this, but we might get all the
9392 template args from other function args. */
9395 /* If PARM uses template parameters, then we can't bail out here,
9396 even if ARG == PARM, since we won't record unifications for the
9397 template parameters. We might need them if we're trying to
9398 figure out which of two things is more specialized. */
9399 if (arg == parm && !uses_template_parms (parm))
9402 /* Immediately reject some pairs that won't unify because of
9403 cv-qualification mismatches. */
9404 if (TREE_CODE (arg) == TREE_CODE (parm)
9406 /* It is the elements of the array which hold the cv quals of an array
9407 type, and the elements might be template type parms. We'll check
9409 && TREE_CODE (arg) != ARRAY_TYPE
9410 /* We check the cv-qualifiers when unifying with template type
9411 parameters below. We want to allow ARG `const T' to unify with
9412 PARM `T' for example, when computing which of two templates
9413 is more specialized, for example. */
9414 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9415 && !check_cv_quals_for_unify (strict_in, arg, parm))
9418 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9419 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9420 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9421 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9422 strict &= ~UNIFY_ALLOW_DERIVED;
9423 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9424 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9425 strict &= ~UNIFY_ALLOW_MAX_CORRECTION;
9427 switch (TREE_CODE (parm))
9431 case UNBOUND_CLASS_TEMPLATE:
9432 /* In a type which contains a nested-name-specifier, template
9433 argument values cannot be deduced for template parameters used
9434 within the nested-name-specifier. */
9437 case TEMPLATE_TYPE_PARM:
9438 case TEMPLATE_TEMPLATE_PARM:
9439 case BOUND_TEMPLATE_TEMPLATE_PARM:
9440 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9442 if (TEMPLATE_TYPE_LEVEL (parm)
9443 != template_decl_level (tparm))
9444 /* The PARM is not one we're trying to unify. Just check
9445 to see if it matches ARG. */
9446 return (TREE_CODE (arg) == TREE_CODE (parm)
9447 && same_type_p (parm, arg)) ? 0 : 1;
9448 idx = TEMPLATE_TYPE_IDX (parm);
9449 targ = TREE_VEC_ELT (targs, idx);
9450 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9452 /* Check for mixed types and values. */
9453 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9454 && TREE_CODE (tparm) != TYPE_DECL)
9455 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9456 && TREE_CODE (tparm) != TEMPLATE_DECL))
9459 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9461 /* ARG must be constructed from a template class or a template
9462 template parameter. */
9463 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9464 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9468 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9469 tree parmvec = TYPE_TI_ARGS (parm);
9470 tree argvec = TYPE_TI_ARGS (arg);
9472 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9475 /* The parameter and argument roles have to be switched here
9476 in order to handle default arguments properly. For example,
9477 template<template <class> class TT> void f(TT<int>)
9478 should be able to accept vector<int> which comes from
9479 template <class T, class Allocator = allocator>
9482 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9486 /* Deduce arguments T, i from TT<T> or TT<i>.
9487 We check each element of PARMVEC and ARGVEC individually
9488 rather than the whole TREE_VEC since they can have
9489 different number of elements. */
9491 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9493 tree t = TREE_VEC_ELT (parmvec, i);
9495 if (unify (tparms, targs, t,
9496 TREE_VEC_ELT (argvec, i),
9501 arg = TYPE_TI_TEMPLATE (arg);
9503 /* Fall through to deduce template name. */
9506 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9507 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9509 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9511 /* Simple cases: Value already set, does match or doesn't. */
9512 if (targ != NULL_TREE && template_args_equal (targ, arg))
9519 /* If PARM is `const T' and ARG is only `int', we don't have
9520 a match unless we are allowing additional qualification.
9521 If ARG is `const int' and PARM is just `T' that's OK;
9522 that binds `const int' to `T'. */
9523 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
9527 /* Consider the case where ARG is `const volatile int' and
9528 PARM is `const T'. Then, T should be `volatile int'. */
9529 arg = cp_build_qualified_type_real
9530 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
9531 if (arg == error_mark_node)
9534 /* Simple cases: Value already set, does match or doesn't. */
9535 if (targ != NULL_TREE && same_type_p (targ, arg))
9540 /* Make sure that ARG is not a variable-sized array. (Note
9541 that were talking about variable-sized arrays (like
9542 `int[n]'), rather than arrays of unknown size (like
9543 `int[]').) We'll get very confused by such a type since
9544 the bound of the array will not be computable in an
9545 instantiation. Besides, such types are not allowed in
9546 ISO C++, so we can do as we please here. */
9547 if (variably_modified_type_p (arg))
9551 TREE_VEC_ELT (targs, idx) = arg;
9554 case TEMPLATE_PARM_INDEX:
9555 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9557 if (TEMPLATE_PARM_LEVEL (parm)
9558 != template_decl_level (tparm))
9559 /* The PARM is not one we're trying to unify. Just check
9560 to see if it matches ARG. */
9561 return !(TREE_CODE (arg) == TREE_CODE (parm)
9562 && cp_tree_equal (parm, arg));
9564 idx = TEMPLATE_PARM_IDX (parm);
9565 targ = TREE_VEC_ELT (targs, idx);
9568 return !cp_tree_equal (targ, arg);
9570 /* [temp.deduct.type] If, in the declaration of a function template
9571 with a non-type template-parameter, the non-type
9572 template-parameter is used in an expression in the function
9573 parameter-list and, if the corresponding template-argument is
9574 deduced, the template-argument type shall match the type of the
9575 template-parameter exactly, except that a template-argument
9576 deduced from an array bound may be of any integral type.
9577 The non-type parameter might use already deduced type parameters. */
9578 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
9579 if (!TREE_TYPE (arg))
9580 /* Template-parameter dependent expression. Just accept it for now.
9581 It will later be processed in convert_template_argument. */
9583 else if (same_type_p (TREE_TYPE (arg), tparm))
9585 else if ((strict & UNIFY_ALLOW_INTEGER)
9586 && (TREE_CODE (tparm) == INTEGER_TYPE
9587 || TREE_CODE (tparm) == BOOLEAN_TYPE))
9589 else if (uses_template_parms (tparm))
9590 /* We haven't deduced the type of this parameter yet. Try again
9596 TREE_VEC_ELT (targs, idx) = arg;
9601 if (TREE_CODE (arg) != POINTER_TYPE)
9604 /* [temp.deduct.call]
9606 A can be another pointer or pointer to member type that can
9607 be converted to the deduced A via a qualification
9608 conversion (_conv.qual_).
9610 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
9611 This will allow for additional cv-qualification of the
9612 pointed-to types if appropriate. */
9614 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
9615 /* The derived-to-base conversion only persists through one
9616 level of pointers. */
9617 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
9619 return unify (tparms, targs, TREE_TYPE (parm),
9620 TREE_TYPE (arg), strict);
9623 case REFERENCE_TYPE:
9624 if (TREE_CODE (arg) != REFERENCE_TYPE)
9626 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9627 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9630 if (TREE_CODE (arg) != ARRAY_TYPE)
9632 if ((TYPE_DOMAIN (parm) == NULL_TREE)
9633 != (TYPE_DOMAIN (arg) == NULL_TREE))
9635 if (TYPE_DOMAIN (parm) != NULL_TREE
9636 && unify (tparms, targs, TYPE_DOMAIN (parm),
9637 TYPE_DOMAIN (arg), UNIFY_ALLOW_NONE) != 0)
9639 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9640 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9648 if (TREE_CODE (arg) != TREE_CODE (parm))
9651 if (TREE_CODE (parm) == INTEGER_TYPE
9652 && TREE_CODE (TYPE_MAX_VALUE (parm)) != INTEGER_CST)
9654 if (TYPE_MIN_VALUE (parm) && TYPE_MIN_VALUE (arg)
9655 && unify (tparms, targs, TYPE_MIN_VALUE (parm),
9656 TYPE_MIN_VALUE (arg), UNIFY_ALLOW_INTEGER))
9658 if (TYPE_MAX_VALUE (parm) && TYPE_MAX_VALUE (arg)
9659 && unify (tparms, targs, TYPE_MAX_VALUE (parm),
9660 TYPE_MAX_VALUE (arg),
9661 UNIFY_ALLOW_INTEGER | UNIFY_ALLOW_MAX_CORRECTION))
9664 /* We have already checked cv-qualification at the top of the
9666 else if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
9669 /* As far as unification is concerned, this wins. Later checks
9670 will invalidate it if necessary. */
9673 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
9674 /* Type INTEGER_CST can come from ordinary constant template args. */
9676 while (TREE_CODE (arg) == NOP_EXPR)
9677 arg = TREE_OPERAND (arg, 0);
9679 if (TREE_CODE (arg) != INTEGER_CST)
9681 return !tree_int_cst_equal (parm, arg);
9686 if (TREE_CODE (arg) != TREE_VEC)
9688 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
9690 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
9691 if (unify (tparms, targs,
9692 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
9700 if (TREE_CODE (arg) != TREE_CODE (parm))
9703 if (TYPE_PTRMEMFUNC_P (parm))
9705 if (!TYPE_PTRMEMFUNC_P (arg))
9708 return unify (tparms, targs,
9709 TYPE_PTRMEMFUNC_FN_TYPE (parm),
9710 TYPE_PTRMEMFUNC_FN_TYPE (arg),
9714 if (CLASSTYPE_TEMPLATE_INFO (parm))
9718 if (strict_in & UNIFY_ALLOW_DERIVED)
9720 /* First, we try to unify the PARM and ARG directly. */
9721 t = try_class_unification (tparms, targs,
9726 /* Fallback to the special case allowed in
9729 If P is a class, and P has the form
9730 template-id, then A can be a derived class of
9731 the deduced A. Likewise, if P is a pointer to
9732 a class of the form template-id, A can be a
9733 pointer to a derived class pointed to by the
9735 t = get_template_base (tparms, targs,
9738 if (! t || t == error_mark_node)
9742 else if (CLASSTYPE_TEMPLATE_INFO (arg)
9743 && (CLASSTYPE_TI_TEMPLATE (parm)
9744 == CLASSTYPE_TI_TEMPLATE (arg)))
9745 /* Perhaps PARM is something like S<U> and ARG is S<int>.
9746 Then, we should unify `int' and `U'. */
9749 /* There's no chance of unification succeeding. */
9752 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
9753 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
9755 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
9761 if (TREE_CODE (arg) != TREE_CODE (parm))
9764 if (unify (tparms, targs, TREE_TYPE (parm),
9765 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
9767 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
9768 TYPE_ARG_TYPES (arg), 1,
9769 DEDUCE_EXACT, 0, -1);
9772 if (TREE_CODE (arg) != OFFSET_TYPE)
9774 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
9775 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
9777 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9781 if (DECL_TEMPLATE_PARM_P (parm))
9782 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
9783 if (arg != decl_constant_value (parm))
9788 /* Matched cases are handled by the ARG == PARM test above. */
9792 if (tree_int_cst_equal (TREE_OPERAND (parm, 1), integer_one_node)
9793 && (strict_in & UNIFY_ALLOW_MAX_CORRECTION))
9795 /* We handle this case specially, since it comes up with
9796 arrays. In particular, something like:
9798 template <int N> void f(int (&x)[N]);
9800 Here, we are trying to unify the range type, which
9801 looks like [0 ... (N - 1)]. */
9803 t1 = TREE_OPERAND (parm, 0);
9804 t2 = TREE_OPERAND (parm, 1);
9806 t = fold (build (PLUS_EXPR, integer_type_node, arg, t2));
9808 return unify (tparms, targs, t1, t, strict);
9810 /* else fall through */
9813 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (parm))))
9816 /* We're looking at an expression. This can happen with
9820 void foo(S<I>, S<I + 2>);
9822 This is a "nondeduced context":
9826 The nondeduced contexts are:
9828 --A type that is a template-id in which one or more of
9829 the template-arguments is an expression that references
9830 a template-parameter.
9832 In these cases, we assume deduction succeeded, but don't
9833 actually infer any unifications. */
9835 if (!uses_template_parms (parm)
9836 && !template_args_equal (parm, arg))
9842 sorry ("use of `%s' in template type unification",
9843 tree_code_name [(int) TREE_CODE (parm)]);
9849 /* Called if RESULT is explicitly instantiated, or is a member of an
9850 explicitly instantiated class, or if using -frepo and the
9851 instantiation of RESULT has been assigned to this file. */
9854 mark_decl_instantiated (tree result, int extern_p)
9856 /* We used to set this unconditionally; we moved that to
9857 do_decl_instantiation so it wouldn't get set on members of
9858 explicit class template instantiations. But we still need to set
9859 it here for the 'extern template' case in order to suppress
9860 implicit instantiations. */
9862 SET_DECL_EXPLICIT_INSTANTIATION (result);
9864 /* If this entity has already been written out, it's too late to
9865 make any modifications. */
9866 if (TREE_ASM_WRITTEN (result))
9869 if (TREE_CODE (result) != FUNCTION_DECL)
9870 /* The TREE_PUBLIC flag for function declarations will have been
9871 set correctly by tsubst. */
9872 TREE_PUBLIC (result) = 1;
9874 /* This might have been set by an earlier implicit instantiation. */
9875 DECL_COMDAT (result) = 0;
9879 DECL_INTERFACE_KNOWN (result) = 1;
9880 DECL_NOT_REALLY_EXTERN (result) = 1;
9882 /* Always make artificials weak. */
9883 if (DECL_ARTIFICIAL (result) && flag_weak)
9884 comdat_linkage (result);
9885 /* For WIN32 we also want to put explicit instantiations in
9886 linkonce sections. */
9887 else if (TREE_PUBLIC (result))
9888 maybe_make_one_only (result);
9891 if (TREE_CODE (result) == FUNCTION_DECL)
9895 /* Given two function templates PAT1 and PAT2, return:
9897 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
9899 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
9900 -1 if PAT2 is more specialized than PAT1.
9901 0 if neither is more specialized.
9903 LEN is passed through to fn_type_unification. */
9906 more_specialized (tree pat1, tree pat2, int deduce, int len)
9911 /* If template argument deduction succeeds, we substitute the
9912 resulting arguments into non-deduced contexts. While doing that,
9913 we must be aware that we may encounter dependent types. */
9914 ++processing_template_decl;
9915 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
9916 NULL_TREE, 0, deduce, len);
9920 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
9921 NULL_TREE, 0, deduce, len);
9924 --processing_template_decl;
9929 /* Given two class template specialization list nodes PAT1 and PAT2, return:
9931 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
9932 -1 if PAT2 is more specialized than PAT1.
9933 0 if neither is more specialized.
9935 FULL_ARGS is the full set of template arguments that triggers this
9936 partial ordering. */
9939 more_specialized_class (tree pat1, tree pat2, tree full_args)
9944 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
9945 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
9949 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
9950 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
9957 /* Return the template arguments that will produce the function signature
9958 DECL from the function template FN, with the explicit template
9959 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
9960 also match. Return NULL_TREE if no satisfactory arguments could be
9961 found. DEDUCE and LEN are passed through to fn_type_unification. */
9964 get_bindings_real (tree fn,
9971 int ntparms = DECL_NTPARMS (fn);
9972 tree targs = make_tree_vec (ntparms);
9974 tree decl_arg_types;
9977 /* Substitute the explicit template arguments into the type of DECL.
9978 The call to fn_type_unification will handle substitution into the
9980 decl_type = TREE_TYPE (decl);
9981 if (explicit_args && uses_template_parms (decl_type))
9984 tree converted_args;
9986 if (DECL_TEMPLATE_INFO (decl))
9987 tmpl = DECL_TI_TEMPLATE (decl);
9989 /* We can get here for some invalid specializations. */
9993 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
9994 explicit_args, NULL_TREE,
9995 tf_none, /*require_all_arguments=*/0));
9996 if (converted_args == error_mark_node)
9999 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10000 if (decl_type == error_mark_node)
10004 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10005 /* Never do unification on the 'this' parameter. */
10006 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10007 decl_arg_types = TREE_CHAIN (decl_arg_types);
10009 i = fn_type_unification (fn, explicit_args, targs,
10011 (check_rettype || DECL_CONV_FN_P (fn)
10012 ? TREE_TYPE (decl_type) : NULL_TREE),
10021 /* For most uses, we want to check the return type. */
10024 get_bindings (tree fn, tree decl, tree explicit_args)
10026 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10029 /* But for resolve_overloaded_unification, we only care about the parameter
10033 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10035 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10038 /* Return the innermost template arguments that, when applied to a
10039 template specialization whose innermost template parameters are
10040 TPARMS, and whose specialization arguments are PARMS, yield the
10043 For example, suppose we have:
10045 template <class T, class U> struct S {};
10046 template <class T> struct S<T*, int> {};
10048 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10049 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10050 int}. The resulting vector will be {double}, indicating that `T'
10051 is bound to `double'. */
10054 get_class_bindings (tree tparms, tree parms, tree args)
10056 int i, ntparms = TREE_VEC_LENGTH (tparms);
10057 tree vec = make_tree_vec (ntparms);
10059 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10063 for (i = 0; i < ntparms; ++i)
10064 if (! TREE_VEC_ELT (vec, i))
10067 if (verify_class_unification (vec, parms, args))
10073 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10074 Pick the most specialized template, and return the corresponding
10075 instantiation, or if there is no corresponding instantiation, the
10076 template itself. If there is no most specialized template,
10077 error_mark_node is returned. If there are no templates at all,
10078 NULL_TREE is returned. */
10081 most_specialized_instantiation (tree instantiations)
10086 if (!instantiations)
10089 champ = instantiations;
10090 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10092 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10100 fn = TREE_CHAIN (fn);
10102 return error_mark_node;
10108 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10110 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10113 return error_mark_node;
10116 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10119 /* Return the most specialized of the list of templates in FNS that can
10120 produce an instantiation matching DECL, given the explicit template
10121 arguments EXPLICIT_ARGS. */
10124 most_specialized (tree fns, tree decl, tree explicit_args)
10126 tree candidates = NULL_TREE;
10129 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10131 tree candidate = TREE_VALUE (fn);
10133 args = get_bindings (candidate, decl, explicit_args);
10135 candidates = tree_cons (NULL_TREE, candidate, candidates);
10138 return most_specialized_instantiation (candidates);
10141 /* If DECL is a specialization of some template, return the most
10142 general such template. Otherwise, returns NULL_TREE.
10144 For example, given:
10146 template <class T> struct S { template <class U> void f(U); };
10148 if TMPL is `template <class U> void S<int>::f(U)' this will return
10149 the full template. This function will not trace past partial
10150 specializations, however. For example, given in addition:
10152 template <class T> struct S<T*> { template <class U> void f(U); };
10154 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10155 `template <class T> template <class U> S<T*>::f(U)'. */
10158 most_general_template (tree decl)
10160 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10161 an immediate specialization. */
10162 if (TREE_CODE (decl) == FUNCTION_DECL)
10164 if (DECL_TEMPLATE_INFO (decl)) {
10165 decl = DECL_TI_TEMPLATE (decl);
10167 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10168 template friend. */
10169 if (TREE_CODE (decl) != TEMPLATE_DECL)
10175 /* Look for more and more general templates. */
10176 while (DECL_TEMPLATE_INFO (decl))
10178 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10179 (See cp-tree.h for details.) */
10180 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10183 if (CLASS_TYPE_P (TREE_TYPE (decl))
10184 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10187 /* Stop if we run into an explicitly specialized class template. */
10188 if (!DECL_NAMESPACE_SCOPE_P (decl)
10189 && DECL_CONTEXT (decl)
10190 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10193 decl = DECL_TI_TEMPLATE (decl);
10199 /* Return the most specialized of the class template specializations
10200 of TMPL which can produce an instantiation matching ARGS, or
10201 error_mark_node if the choice is ambiguous. */
10204 most_specialized_class (tree tmpl, tree args)
10206 tree list = NULL_TREE;
10211 tmpl = most_general_template (tmpl);
10212 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10215 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10218 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10219 TREE_TYPE (list) = TREE_TYPE (t);
10228 t = TREE_CHAIN (t);
10229 for (; t; t = TREE_CHAIN (t))
10231 fate = more_specialized_class (champ, t, args);
10238 t = TREE_CHAIN (t);
10240 return error_mark_node;
10246 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10248 fate = more_specialized_class (champ, t, args);
10250 return error_mark_node;
10256 /* Explicitly instantiate DECL. */
10259 do_decl_instantiation (tree decl, tree storage)
10261 tree result = NULL_TREE;
10265 /* An error occurred, for which grokdeclarator has already issued
10266 an appropriate message. */
10268 else if (! DECL_LANG_SPECIFIC (decl))
10270 error ("explicit instantiation of non-template `%#D'", decl);
10273 else if (TREE_CODE (decl) == VAR_DECL)
10275 /* There is an asymmetry here in the way VAR_DECLs and
10276 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10277 the latter, the DECL we get back will be marked as a
10278 template instantiation, and the appropriate
10279 DECL_TEMPLATE_INFO will be set up. This does not happen for
10280 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10281 should handle VAR_DECLs as it currently handles
10283 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10284 if (!result || TREE_CODE (result) != VAR_DECL)
10286 error ("no matching template for `%D' found", decl);
10290 else if (TREE_CODE (decl) != FUNCTION_DECL)
10292 error ("explicit instantiation of `%#D'", decl);
10298 /* Check for various error cases. Note that if the explicit
10299 instantiation is valid the RESULT will currently be marked as an
10300 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10301 until we get here. */
10303 if (DECL_TEMPLATE_SPECIALIZATION (result))
10305 /* DR 259 [temp.spec].
10307 Both an explicit instantiation and a declaration of an explicit
10308 specialization shall not appear in a program unless the explicit
10309 instantiation follows a declaration of the explicit specialization.
10311 For a given set of template parameters, if an explicit
10312 instantiation of a template appears after a declaration of an
10313 explicit specialization for that template, the explicit
10314 instantiation has no effect. */
10317 else if (DECL_EXPLICIT_INSTANTIATION (result))
10321 No program shall explicitly instantiate any template more
10324 We check DECL_INTERFACE_KNOWN so as not to complain when the first
10325 instantiation was `extern' and the second is not, and EXTERN_P for
10326 the opposite case. If -frepo, chances are we already got marked
10327 as an explicit instantiation because of the repo file. */
10328 if (DECL_INTERFACE_KNOWN (result) && !extern_p && !flag_use_repository)
10329 pedwarn ("duplicate explicit instantiation of `%#D'", result);
10331 /* If we've already instantiated the template, just return now. */
10332 if (DECL_INTERFACE_KNOWN (result))
10335 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10337 error ("no matching template for `%D' found", result);
10340 else if (!DECL_TEMPLATE_INFO (result))
10342 pedwarn ("explicit instantiation of non-template `%#D'", result);
10346 if (flag_external_templates)
10349 if (storage == NULL_TREE)
10351 else if (storage == ridpointers[(int) RID_EXTERN])
10353 if (pedantic && !in_system_header)
10354 pedwarn ("ISO C++ forbids the use of `extern' on explicit instantiations");
10358 error ("storage class `%D' applied to template instantiation",
10361 SET_DECL_EXPLICIT_INSTANTIATION (result);
10362 mark_decl_instantiated (result, extern_p);
10363 repo_template_instantiated (result, extern_p);
10365 instantiate_decl (result, /*defer_ok=*/1);
10369 mark_class_instantiated (tree t, int extern_p)
10371 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10372 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10373 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10374 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10377 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10378 rest_of_type_compilation (t, 1);
10382 /* Called from do_type_instantiation through binding_table_foreach to
10383 do recursive instantiation for the type bound in ENTRY. */
10385 bt_instantiate_type_proc (binding_entry entry, void *data)
10387 tree storage = *(tree *) data;
10389 if (IS_AGGR_TYPE (entry->type)
10390 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10391 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10394 /* Perform an explicit instantiation of template class T. STORAGE, if
10395 non-null, is the RID for extern, inline or static. COMPLAIN is
10396 nonzero if this is called from the parser, zero if called recursively,
10397 since the standard is unclear (as detailed below). */
10400 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10406 if (TREE_CODE (t) == TYPE_DECL)
10409 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10411 error ("explicit instantiation of non-template type `%T'", t);
10417 /* With -fexternal-templates, explicit instantiations are treated the same
10418 as implicit ones. */
10419 if (flag_external_templates)
10422 if (!COMPLETE_TYPE_P (t))
10424 if (complain & tf_error)
10425 error ("explicit instantiation of `%#T' before definition of template",
10430 if (storage != NULL_TREE)
10432 if (pedantic && !in_system_header)
10433 pedwarn("ISO C++ forbids the use of `%s' on explicit instantiations",
10434 IDENTIFIER_POINTER (storage));
10436 if (storage == ridpointers[(int) RID_INLINE])
10438 else if (storage == ridpointers[(int) RID_EXTERN])
10440 else if (storage == ridpointers[(int) RID_STATIC])
10444 error ("storage class `%D' applied to template instantiation",
10450 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10452 /* DR 259 [temp.spec].
10454 Both an explicit instantiation and a declaration of an explicit
10455 specialization shall not appear in a program unless the explicit
10456 instantiation follows a declaration of the explicit specialization.
10458 For a given set of template parameters, if an explicit
10459 instantiation of a template appears after a declaration of an
10460 explicit specialization for that template, the explicit
10461 instantiation has no effect. */
10464 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10468 No program shall explicitly instantiate any template more
10471 If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation
10472 was `extern'. If EXTERN_P then the second is. If -frepo, chances
10473 are we already got marked as an explicit instantiation because of the
10474 repo file. All these cases are OK. */
10475 if (!CLASSTYPE_INTERFACE_ONLY (t) && !extern_p && !flag_use_repository
10476 && (complain & tf_error))
10477 pedwarn ("duplicate explicit instantiation of `%#T'", t);
10479 /* If we've already instantiated the template, just return now. */
10480 if (!CLASSTYPE_INTERFACE_ONLY (t))
10484 mark_class_instantiated (t, extern_p);
10485 repo_template_instantiated (t, extern_p);
10493 /* In contrast to implicit instantiation, where only the
10494 declarations, and not the definitions, of members are
10495 instantiated, we have here:
10499 The explicit instantiation of a class template specialization
10500 implies the instantiation of all of its members not
10501 previously explicitly specialized in the translation unit
10502 containing the explicit instantiation.
10504 Of course, we can't instantiate member template classes, since
10505 we don't have any arguments for them. Note that the standard
10506 is unclear on whether the instantiation of the members are
10507 *explicit* instantiations or not. We choose to be generous,
10508 and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow
10509 the explicit instantiation of a class where some of the members
10510 have no definition in the current translation unit. */
10513 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
10514 if (TREE_CODE (tmp) == FUNCTION_DECL
10515 && DECL_TEMPLATE_INSTANTIATION (tmp))
10517 mark_decl_instantiated (tmp, extern_p);
10518 repo_template_instantiated (tmp, extern_p);
10520 instantiate_decl (tmp, /*defer_ok=*/1);
10523 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
10524 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
10526 mark_decl_instantiated (tmp, extern_p);
10527 repo_template_instantiated (tmp, extern_p);
10529 instantiate_decl (tmp, /*defer_ok=*/1);
10532 if (CLASSTYPE_NESTED_UTDS (t))
10533 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
10534 bt_instantiate_type_proc, &storage);
10538 /* Given a function DECL, which is a specialization of TMPL, modify
10539 DECL to be a re-instantiation of TMPL with the same template
10540 arguments. TMPL should be the template into which tsubst'ing
10541 should occur for DECL, not the most general template.
10543 One reason for doing this is a scenario like this:
10546 void f(const T&, int i);
10548 void g() { f(3, 7); }
10551 void f(const T& t, const int i) { }
10553 Note that when the template is first instantiated, with
10554 instantiate_template, the resulting DECL will have no name for the
10555 first parameter, and the wrong type for the second. So, when we go
10556 to instantiate the DECL, we regenerate it. */
10559 regenerate_decl_from_template (tree decl, tree tmpl)
10561 /* The most general version of TMPL. */
10563 /* The arguments used to instantiate DECL, from the most general
10570 args = DECL_TI_ARGS (decl);
10571 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
10573 /* Unregister the specialization so that when we tsubst we will not
10574 just return DECL. We don't have to unregister DECL from TMPL
10575 because if would only be registered there if it were a partial
10576 instantiation of a specialization, which it isn't: it's a full
10578 gen_tmpl = most_general_template (tmpl);
10579 unregistered = reregister_specialization (decl, gen_tmpl,
10580 /*new_spec=*/NULL_TREE);
10582 /* If the DECL was not unregistered then something peculiar is
10583 happening: we created a specialization but did not call
10584 register_specialization for it. */
10585 my_friendly_assert (unregistered, 0);
10587 /* Make sure that we can see identifiers, and compute access
10589 push_access_scope (decl);
10591 /* Do the substitution to get the new declaration. */
10592 new_decl = tsubst (code_pattern, args, tf_error, NULL_TREE);
10594 if (TREE_CODE (decl) == VAR_DECL)
10596 /* Set up DECL_INITIAL, since tsubst doesn't. */
10597 if (!DECL_INITIALIZED_IN_CLASS_P (decl))
10598 DECL_INITIAL (new_decl) =
10599 tsubst_expr (DECL_INITIAL (code_pattern), args,
10600 tf_error, DECL_TI_TEMPLATE (decl));
10602 else if (TREE_CODE (decl) == FUNCTION_DECL)
10604 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
10606 DECL_INITIAL (new_decl) = error_mark_node;
10607 /* And don't complain about a duplicate definition. */
10608 DECL_INITIAL (decl) = NULL_TREE;
10611 pop_access_scope (decl);
10613 /* The immediate parent of the new template is still whatever it was
10614 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
10615 general template. We also reset the DECL_ASSEMBLER_NAME since
10616 tsubst always calculates the name as if the function in question
10617 were really a template instance, and sometimes, with friend
10618 functions, this is not so. See tsubst_friend_function for
10620 DECL_TI_TEMPLATE (new_decl) = DECL_TI_TEMPLATE (decl);
10621 COPY_DECL_ASSEMBLER_NAME (decl, new_decl);
10622 COPY_DECL_RTL (decl, new_decl);
10623 DECL_USE_TEMPLATE (new_decl) = DECL_USE_TEMPLATE (decl);
10625 /* Call duplicate decls to merge the old and new declarations. */
10626 duplicate_decls (new_decl, decl);
10628 /* Now, re-register the specialization. */
10629 register_specialization (decl, gen_tmpl, args);
10632 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
10633 substituted to get DECL. */
10636 template_for_substitution (tree decl)
10638 tree tmpl = DECL_TI_TEMPLATE (decl);
10640 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
10641 for the instantiation. This is not always the most general
10642 template. Consider, for example:
10645 struct S { template <class U> void f();
10646 template <> void f<int>(); };
10648 and an instantiation of S<double>::f<int>. We want TD to be the
10649 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
10650 while (/* An instantiation cannot have a definition, so we need a
10651 more general template. */
10652 DECL_TEMPLATE_INSTANTIATION (tmpl)
10653 /* We must also deal with friend templates. Given:
10655 template <class T> struct S {
10656 template <class U> friend void f() {};
10659 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
10660 so far as the language is concerned, but that's still
10661 where we get the pattern for the instantiation from. On
10662 other hand, if the definition comes outside the class, say:
10664 template <class T> struct S {
10665 template <class U> friend void f();
10667 template <class U> friend void f() {}
10669 we don't need to look any further. That's what the check for
10670 DECL_INITIAL is for. */
10671 || (TREE_CODE (decl) == FUNCTION_DECL
10672 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
10673 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
10675 /* The present template, TD, should not be a definition. If it
10676 were a definition, we should be using it! Note that we
10677 cannot restructure the loop to just keep going until we find
10678 a template with a definition, since that might go too far if
10679 a specialization was declared, but not defined. */
10680 my_friendly_assert (!(TREE_CODE (decl) == VAR_DECL
10681 && !DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl))),
10684 /* Fetch the more general template. */
10685 tmpl = DECL_TI_TEMPLATE (tmpl);
10691 /* Produce the definition of D, a _DECL generated from a template. If
10692 DEFER_OK is nonzero, then we don't have to actually do the
10693 instantiation now; we just have to do it sometime. */
10696 instantiate_decl (tree d, int defer_ok)
10698 tree tmpl = DECL_TI_TEMPLATE (d);
10705 int pattern_defined;
10707 location_t saved_loc = input_location;
10709 /* This function should only be used to instantiate templates for
10710 functions and static member variables. */
10711 my_friendly_assert (TREE_CODE (d) == FUNCTION_DECL
10712 || TREE_CODE (d) == VAR_DECL, 0);
10714 /* Variables are never deferred; if instantiation is required, they
10715 are instantiated right away. That allows for better code in the
10716 case that an expression refers to the value of the variable --
10717 if the variable has a constant value the referring expression can
10718 take advantage of that fact. */
10719 if (TREE_CODE (d) == VAR_DECL)
10722 /* Don't instantiate cloned functions. Instead, instantiate the
10723 functions they cloned. */
10724 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
10725 d = DECL_CLONED_FUNCTION (d);
10727 if (DECL_TEMPLATE_INSTANTIATED (d))
10728 /* D has already been instantiated. It might seem reasonable to
10729 check whether or not D is an explicit instantiation, and, if so,
10730 stop here. But when an explicit instantiation is deferred
10731 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
10732 is set, even though we still need to do the instantiation. */
10735 /* If we already have a specialization of this declaration, then
10736 there's no reason to instantiate it. Note that
10737 retrieve_specialization gives us both instantiations and
10738 specializations, so we must explicitly check
10739 DECL_TEMPLATE_SPECIALIZATION. */
10740 gen_tmpl = most_general_template (tmpl);
10741 gen_args = DECL_TI_ARGS (d);
10742 spec = retrieve_specialization (gen_tmpl, gen_args);
10743 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
10746 /* This needs to happen before any tsubsting. */
10747 if (! push_tinst_level (d))
10750 timevar_push (TV_PARSE);
10752 /* We may be in the middle of deferred access check. Disable it now. */
10753 push_deferring_access_checks (dk_no_deferred);
10755 /* Our caller does not expect collection to happen, which it might if
10756 we decide to compile the function to rtl now. Arrange for a new
10757 gc context to be created if so. */
10760 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
10761 for the instantiation. */
10762 td = template_for_substitution (d);
10763 code_pattern = DECL_TEMPLATE_RESULT (td);
10765 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
10766 || DECL_TEMPLATE_SPECIALIZATION (td))
10767 /* In the case of a friend template whose definition is provided
10768 outside the class, we may have too many arguments. Drop the
10769 ones we don't need. The same is true for specializations. */
10770 args = get_innermost_template_args
10771 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
10775 if (TREE_CODE (d) == FUNCTION_DECL)
10776 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
10778 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
10780 input_location = DECL_SOURCE_LOCATION (d);
10782 if (pattern_defined)
10784 /* Let the repository code that this template definition is
10787 The repository doesn't need to know about cloned functions
10788 because they never actually show up in the object file. It
10789 does need to know about the clones; those are the symbols
10790 that the linker will be emitting error messages about. */
10791 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (d)
10792 || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (d))
10796 for (t = TREE_CHAIN (d);
10797 t && DECL_CLONED_FUNCTION_P (t);
10798 t = TREE_CHAIN (t))
10799 repo_template_used (t);
10802 repo_template_used (d);
10804 if (flag_external_templates && ! DECL_INTERFACE_KNOWN (d))
10806 if (flag_alt_external_templates)
10808 if (interface_unknown)
10809 warn_if_unknown_interface (d);
10811 else if (DECL_INTERFACE_KNOWN (code_pattern))
10813 DECL_INTERFACE_KNOWN (d) = 1;
10814 DECL_NOT_REALLY_EXTERN (d) = ! DECL_EXTERNAL (code_pattern);
10817 warn_if_unknown_interface (code_pattern);
10821 import_export_decl (d);
10826 /* Recheck the substitutions to obtain any warning messages
10827 about ignoring cv qualifiers. */
10828 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
10829 tree type = TREE_TYPE (gen);
10831 /* Make sure that we can see identifiers, and compute access
10832 correctly. D is already the target FUNCTION_DECL with the
10834 push_access_scope (d);
10836 if (TREE_CODE (gen) == FUNCTION_DECL)
10838 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
10839 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
10840 tf_error | tf_warning, d);
10841 /* Don't simply tsubst the function type, as that will give
10842 duplicate warnings about poor parameter qualifications.
10843 The function arguments are the same as the decl_arguments
10844 without the top level cv qualifiers. */
10845 type = TREE_TYPE (type);
10847 tsubst (type, gen_args, tf_error | tf_warning, d);
10849 pop_access_scope (d);
10852 if (TREE_CODE (d) == VAR_DECL && DECL_INITIALIZED_IN_CLASS_P (d)
10853 && DECL_INITIAL (d) == NULL_TREE)
10854 /* We should have set up DECL_INITIAL in instantiate_class_template. */
10856 /* Reject all external templates except inline functions. */
10857 else if (DECL_INTERFACE_KNOWN (d)
10858 && ! DECL_NOT_REALLY_EXTERN (d)
10859 && ! (TREE_CODE (d) == FUNCTION_DECL
10860 && DECL_INLINE (d)))
10862 /* Defer all other templates, unless we have been explicitly
10863 forbidden from doing so. We restore the source position here
10864 because it's used by add_pending_template. */
10865 else if (! pattern_defined || defer_ok)
10867 input_location = saved_loc;
10869 if (at_eof && !pattern_defined
10870 && DECL_EXPLICIT_INSTANTIATION (d))
10873 The definition of a non-exported function template, a
10874 non-exported member function template, or a non-exported
10875 member function or static data member of a class template
10876 shall be present in every translation unit in which it is
10877 explicitly instantiated. */
10879 ("explicit instantiation of `%D' but no definition available", d);
10881 add_pending_template (d);
10885 need_push = !global_bindings_p ();
10887 push_to_top_level ();
10889 /* Regenerate the declaration in case the template has been modified
10890 by a subsequent redeclaration. */
10891 regenerate_decl_from_template (d, td);
10893 /* We already set the file and line above. Reset them now in case
10894 they changed as a result of calling
10895 regenerate_decl_from_template. */
10896 input_location = DECL_SOURCE_LOCATION (d);
10898 if (TREE_CODE (d) == VAR_DECL)
10900 /* Clear out DECL_RTL; whatever was there before may not be right
10901 since we've reset the type of the declaration. */
10902 SET_DECL_RTL (d, NULL_RTX);
10904 DECL_IN_AGGR_P (d) = 0;
10905 import_export_decl (d);
10906 DECL_EXTERNAL (d) = ! DECL_NOT_REALLY_EXTERN (d);
10908 if (DECL_EXTERNAL (d))
10910 /* The fact that this code is executing indicates that:
10912 (1) D is a template static data member, for which a
10913 definition is available.
10915 (2) An implicit or explicit instantiation has occurred.
10917 (3) We are not going to emit a definition of the static
10918 data member at this time.
10920 This situation is peculiar, but it occurs on platforms
10921 without weak symbols when performing an implicit
10922 instantiation. There, we cannot implicitly instantiate a
10923 defined static data member in more than one translation
10924 unit, so import_export_decl marks the declaration as
10925 external; we must rely on explicit instantiation. */
10929 /* Mark D as instantiated so that recursive calls to
10930 instantiate_decl do not try to instantiate it again. */
10931 DECL_TEMPLATE_INSTANTIATED (d) = 1;
10933 (!DECL_INITIALIZED_IN_CLASS_P (d)
10934 ? DECL_INITIAL (d) : NULL_TREE),
10938 else if (TREE_CODE (d) == FUNCTION_DECL)
10940 htab_t saved_local_specializations;
10945 /* Mark D as instantiated so that recursive calls to
10946 instantiate_decl do not try to instantiate it again. */
10947 DECL_TEMPLATE_INSTANTIATED (d) = 1;
10949 /* Save away the current list, in case we are instantiating one
10950 template from within the body of another. */
10951 saved_local_specializations = local_specializations;
10953 /* Set up the list of local specializations. */
10954 local_specializations = htab_create (37,
10955 hash_local_specialization,
10956 eq_local_specializations,
10959 /* Set up context. */
10960 import_export_decl (d);
10961 start_function (NULL_TREE, d, NULL_TREE, SF_PRE_PARSED);
10963 /* Create substitution entries for the parameters. */
10964 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
10965 tmpl_parm = DECL_ARGUMENTS (subst_decl);
10966 spec_parm = DECL_ARGUMENTS (d);
10967 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
10969 register_local_specialization (spec_parm, tmpl_parm);
10970 spec_parm = skip_artificial_parms_for (d, spec_parm);
10971 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
10975 register_local_specialization (spec_parm, tmpl_parm);
10976 tmpl_parm = TREE_CHAIN (tmpl_parm);
10977 spec_parm = TREE_CHAIN (spec_parm);
10979 my_friendly_assert (!spec_parm, 20020813);
10981 /* Substitute into the body of the function. */
10982 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
10983 tf_error | tf_warning, tmpl);
10985 /* We don't need the local specializations any more. */
10986 htab_delete (local_specializations);
10987 local_specializations = saved_local_specializations;
10989 /* Finish the function. */
10990 d = finish_function (0);
10991 expand_or_defer_fn (d);
10994 /* We're not deferring instantiation any more. */
10995 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
10998 pop_from_top_level ();
11001 input_location = saved_loc;
11002 pop_deferring_access_checks ();
11003 pop_tinst_level ();
11006 timevar_pop (TV_PARSE);
11011 /* Run through the list of templates that we wish we could
11012 instantiate, and instantiate any we can. */
11015 instantiate_pending_templates (void)
11018 tree last = NULL_TREE;
11019 int instantiated_something = 0;
11026 t = &pending_templates;
11029 tree instantiation = TREE_VALUE (*t);
11031 reopen_tinst_level (TREE_PURPOSE (*t));
11033 if (TYPE_P (instantiation))
11037 if (!COMPLETE_TYPE_P (instantiation))
11039 instantiate_class_template (instantiation);
11040 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11041 for (fn = TYPE_METHODS (instantiation);
11043 fn = TREE_CHAIN (fn))
11044 if (! DECL_ARTIFICIAL (fn))
11045 instantiate_decl (fn, /*defer_ok=*/0);
11046 if (COMPLETE_TYPE_P (instantiation))
11048 instantiated_something = 1;
11053 if (COMPLETE_TYPE_P (instantiation))
11054 /* If INSTANTIATION has been instantiated, then we don't
11055 need to consider it again in the future. */
11056 *t = TREE_CHAIN (*t);
11060 t = &TREE_CHAIN (*t);
11065 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11066 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11068 instantiation = instantiate_decl (instantiation,
11070 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11072 instantiated_something = 1;
11077 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11078 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11079 /* If INSTANTIATION has been instantiated, then we don't
11080 need to consider it again in the future. */
11081 *t = TREE_CHAIN (*t);
11085 t = &TREE_CHAIN (*t);
11089 current_tinst_level = NULL_TREE;
11091 last_pending_template = last;
11093 while (reconsider);
11095 return instantiated_something;
11098 /* Substitute ARGVEC into T, which is a list of initializers for
11099 either base class or a non-static data member. The TREE_PURPOSEs
11100 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11101 instantiate_decl. */
11104 tsubst_initializer_list (tree t, tree argvec)
11106 tree inits = NULL_TREE;
11108 for (; t; t = TREE_CHAIN (t))
11114 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11116 decl = expand_member_init (decl);
11117 if (decl && !DECL_P (decl))
11118 in_base_initializer = 1;
11120 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11124 else if (TREE_CODE (init) == TREE_LIST)
11125 for (val = init; val; val = TREE_CHAIN (val))
11126 TREE_VALUE (val) = convert_from_reference (TREE_VALUE (val));
11127 else if (init != void_type_node)
11128 init = convert_from_reference (init);
11130 in_base_initializer = 0;
11134 init = build_tree_list (decl, init);
11135 TREE_CHAIN (init) = inits;
11142 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11145 set_current_access_from_decl (tree decl)
11147 if (TREE_PRIVATE (decl))
11148 current_access_specifier = access_private_node;
11149 else if (TREE_PROTECTED (decl))
11150 current_access_specifier = access_protected_node;
11152 current_access_specifier = access_public_node;
11155 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11156 is the instantiation (which should have been created with
11157 start_enum) and ARGS are the template arguments to use. */
11160 tsubst_enum (tree tag, tree newtag, tree args)
11164 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11169 decl = TREE_VALUE (e);
11170 /* Note that in a template enum, the TREE_VALUE is the
11171 CONST_DECL, not the corresponding INTEGER_CST. */
11172 value = tsubst_expr (DECL_INITIAL (decl),
11173 args, tf_error | tf_warning,
11176 /* Give this enumeration constant the correct access. */
11177 set_current_access_from_decl (decl);
11179 /* Actually build the enumerator itself. */
11180 build_enumerator (DECL_NAME (decl), value, newtag);
11183 finish_enum (newtag);
11184 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11185 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11188 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11189 its type -- but without substituting the innermost set of template
11190 arguments. So, innermost set of template parameters will appear in
11194 get_mostly_instantiated_function_type (tree decl)
11202 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11203 targs = DECL_TI_ARGS (decl);
11204 tparms = DECL_TEMPLATE_PARMS (tmpl);
11205 parm_depth = TMPL_PARMS_DEPTH (tparms);
11207 /* There should be as many levels of arguments as there are levels
11209 my_friendly_assert (parm_depth == TMPL_ARGS_DEPTH (targs), 0);
11211 fn_type = TREE_TYPE (tmpl);
11213 if (parm_depth == 1)
11214 /* No substitution is necessary. */
11221 /* Replace the innermost level of the TARGS with NULL_TREEs to
11222 let tsubst know not to substitute for those parameters. */
11223 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11224 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11225 SET_TMPL_ARGS_LEVEL (partial_args, i,
11226 TMPL_ARGS_LEVEL (targs, i));
11227 SET_TMPL_ARGS_LEVEL (partial_args,
11228 TMPL_ARGS_DEPTH (targs),
11229 make_tree_vec (DECL_NTPARMS (tmpl)));
11231 /* Make sure that we can see identifiers, and compute access
11232 correctly. We can just use the context of DECL for the
11233 partial substitution here. It depends only on outer template
11234 parameters, regardless of whether the innermost level is
11235 specialized or not. */
11236 push_access_scope (decl);
11238 /* Now, do the (partial) substitution to figure out the
11239 appropriate function type. */
11240 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11242 /* Substitute into the template parameters to obtain the real
11243 innermost set of parameters. This step is important if the
11244 innermost set of template parameters contains value
11245 parameters whose types depend on outer template parameters. */
11246 TREE_VEC_LENGTH (partial_args)--;
11247 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11249 pop_access_scope (decl);
11255 /* Return truthvalue if we're processing a template different from
11256 the last one involved in diagnostics. */
11258 problematic_instantiation_changed (void)
11260 return last_template_error_tick != tinst_level_tick;
11263 /* Remember current template involved in diagnostics. */
11265 record_last_problematic_instantiation (void)
11267 last_template_error_tick = tinst_level_tick;
11271 current_instantiation (void)
11273 return current_tinst_level;
11276 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11277 type. Return zero for ok, nonzero for disallowed. Issue error and
11278 warning messages under control of COMPLAIN. */
11281 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11283 if (INTEGRAL_TYPE_P (type))
11285 else if (POINTER_TYPE_P (type))
11287 else if (TYPE_PTR_TO_MEMBER_P (type))
11289 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11291 else if (TREE_CODE (type) == TYPENAME_TYPE)
11294 if (complain & tf_error)
11295 error ("`%#T' is not a valid type for a template constant parameter",
11300 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11301 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11304 dependent_type_p_r (tree type)
11310 A type is dependent if it is:
11312 -- a template parameter. */
11313 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11315 /* -- a qualified-id with a nested-name-specifier which contains a
11316 class-name that names a dependent type or whose unqualified-id
11317 names a dependent type. */
11318 if (TREE_CODE (type) == TYPENAME_TYPE)
11320 /* -- a cv-qualified type where the cv-unqualified type is
11322 type = TYPE_MAIN_VARIANT (type);
11323 /* -- a compound type constructed from any dependent type. */
11324 if (TYPE_PTR_TO_MEMBER_P (type))
11325 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11326 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11328 else if (TREE_CODE (type) == POINTER_TYPE
11329 || TREE_CODE (type) == REFERENCE_TYPE)
11330 return dependent_type_p (TREE_TYPE (type));
11331 else if (TREE_CODE (type) == FUNCTION_TYPE
11332 || TREE_CODE (type) == METHOD_TYPE)
11336 if (dependent_type_p (TREE_TYPE (type)))
11338 for (arg_type = TYPE_ARG_TYPES (type);
11340 arg_type = TREE_CHAIN (arg_type))
11341 if (dependent_type_p (TREE_VALUE (arg_type)))
11345 /* -- an array type constructed from any dependent type or whose
11346 size is specified by a constant expression that is
11347 value-dependent. */
11348 if (TREE_CODE (type) == ARRAY_TYPE)
11350 if (TYPE_DOMAIN (type)
11351 && ((value_dependent_expression_p
11352 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11353 || (type_dependent_expression_p
11354 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11356 return dependent_type_p (TREE_TYPE (type));
11359 /* -- a template-id in which either the template name is a template
11361 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11363 /* ... or any of the template arguments is a dependent type or
11364 an expression that is type-dependent or value-dependent. */
11365 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11366 && (any_dependent_template_arguments_p
11367 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11370 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11371 expression is not type-dependent, then it should already been
11373 if (TREE_CODE (type) == TYPEOF_TYPE)
11376 /* The standard does not specifically mention types that are local
11377 to template functions or local classes, but they should be
11378 considered dependent too. For example:
11380 template <int I> void f() {
11385 The size of `E' cannot be known until the value of `I' has been
11386 determined. Therefore, `E' must be considered dependent. */
11387 scope = TYPE_CONTEXT (type);
11388 if (scope && TYPE_P (scope))
11389 return dependent_type_p (scope);
11390 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11391 return type_dependent_expression_p (scope);
11393 /* Other types are non-dependent. */
11397 /* Returns TRUE if TYPE is dependent, in the sense of
11398 [temp.dep.type]. */
11401 dependent_type_p (tree type)
11403 /* If there are no template parameters in scope, then there can't be
11404 any dependent types. */
11405 if (!processing_template_decl)
11408 /* If the type is NULL, we have not computed a type for the entity
11409 in question; in that case, the type is dependent. */
11413 /* Erroneous types can be considered non-dependent. */
11414 if (type == error_mark_node)
11417 /* If we have not already computed the appropriate value for TYPE,
11419 if (!TYPE_DEPENDENT_P_VALID (type))
11421 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11422 TYPE_DEPENDENT_P_VALID (type) = 1;
11425 return TYPE_DEPENDENT_P (type);
11428 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11431 dependent_scope_ref_p (tree expression, bool criterion (tree))
11436 my_friendly_assert (TREE_CODE (expression) == SCOPE_REF, 20030714);
11438 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11441 scope = TREE_OPERAND (expression, 0);
11442 name = TREE_OPERAND (expression, 1);
11446 An id-expression is type-dependent if it contains a
11447 nested-name-specifier that contains a class-name that names a
11449 /* The suggested resolution to Core Issue 2 implies that if the
11450 qualifying type is the current class, then we must peek
11453 && currently_open_class (scope)
11454 && !criterion (name))
11456 if (dependent_type_p (scope))
11462 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11463 [temp.dep.constexpr] */
11466 value_dependent_expression_p (tree expression)
11468 if (!processing_template_decl)
11471 /* A name declared with a dependent type. */
11472 if (TREE_CODE (expression) == IDENTIFIER_NODE
11473 || (DECL_P (expression)
11474 && type_dependent_expression_p (expression)))
11476 /* A non-type template parameter. */
11477 if ((TREE_CODE (expression) == CONST_DECL
11478 && DECL_TEMPLATE_PARM_P (expression))
11479 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11481 /* A constant with integral or enumeration type and is initialized
11482 with an expression that is value-dependent. */
11483 if (TREE_CODE (expression) == VAR_DECL
11484 && DECL_INITIAL (expression)
11485 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11486 && value_dependent_expression_p (DECL_INITIAL (expression)))
11488 /* These expressions are value-dependent if the type to which the
11489 cast occurs is dependent or the expression being casted is
11490 value-dependent. */
11491 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11492 || TREE_CODE (expression) == STATIC_CAST_EXPR
11493 || TREE_CODE (expression) == CONST_CAST_EXPR
11494 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11495 || TREE_CODE (expression) == CAST_EXPR)
11497 if (dependent_type_p (TREE_TYPE (expression)))
11499 /* A functional cast has a list of operands. */
11500 expression = TREE_OPERAND (expression, 0);
11501 if (TREE_CODE (expression) == TREE_LIST)
11505 if (value_dependent_expression_p (TREE_VALUE (expression)))
11507 expression = TREE_CHAIN (expression);
11509 while (expression);
11513 return value_dependent_expression_p (expression);
11515 /* A `sizeof' expression is value-dependent if the operand is
11517 if (TREE_CODE (expression) == SIZEOF_EXPR
11518 || TREE_CODE (expression) == ALIGNOF_EXPR)
11520 expression = TREE_OPERAND (expression, 0);
11521 if (TYPE_P (expression))
11522 return dependent_type_p (expression);
11523 return type_dependent_expression_p (expression);
11525 if (TREE_CODE (expression) == SCOPE_REF)
11526 return dependent_scope_ref_p (expression, value_dependent_expression_p);
11527 /* A constant expression is value-dependent if any subexpression is
11528 value-dependent. */
11529 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (expression))))
11531 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
11534 return (value_dependent_expression_p
11535 (TREE_OPERAND (expression, 0)));
11538 return ((value_dependent_expression_p
11539 (TREE_OPERAND (expression, 0)))
11540 || (value_dependent_expression_p
11541 (TREE_OPERAND (expression, 1))));
11545 for (i = 0; i < first_rtl_op (TREE_CODE (expression)); ++i)
11546 /* In some cases, some of the operands may be missing.
11547 (For example, in the case of PREDECREMENT_EXPR, the
11548 amount to increment by may be missing.) That doesn't
11549 make the expression dependent. */
11550 if (TREE_OPERAND (expression, i)
11551 && (value_dependent_expression_p
11552 (TREE_OPERAND (expression, i))))
11559 /* The expression is not value-dependent. */
11563 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11564 [temp.dep.expr]. */
11567 type_dependent_expression_p (tree expression)
11569 if (!processing_template_decl)
11572 if (expression == error_mark_node)
11575 /* An unresolved name is always dependent. */
11576 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11579 /* Some expression forms are never type-dependent. */
11580 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
11581 || TREE_CODE (expression) == SIZEOF_EXPR
11582 || TREE_CODE (expression) == ALIGNOF_EXPR
11583 || TREE_CODE (expression) == TYPEID_EXPR
11584 || TREE_CODE (expression) == DELETE_EXPR
11585 || TREE_CODE (expression) == VEC_DELETE_EXPR
11586 || TREE_CODE (expression) == THROW_EXPR)
11589 /* The types of these expressions depends only on the type to which
11590 the cast occurs. */
11591 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11592 || TREE_CODE (expression) == STATIC_CAST_EXPR
11593 || TREE_CODE (expression) == CONST_CAST_EXPR
11594 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11595 || TREE_CODE (expression) == CAST_EXPR)
11596 return dependent_type_p (TREE_TYPE (expression));
11598 /* The types of these expressions depends only on the type created
11599 by the expression. */
11600 if (TREE_CODE (expression) == NEW_EXPR
11601 || TREE_CODE (expression) == VEC_NEW_EXPR)
11603 /* For NEW_EXPR tree nodes created inside a template, either
11604 the object type itself or a TREE_LIST may appear as the
11606 tree type = TREE_OPERAND (expression, 1);
11607 if (TREE_CODE (type) == TREE_LIST)
11608 /* This is an array type. We need to check array dimensions
11610 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
11611 || value_dependent_expression_p
11612 (TREE_OPERAND (TREE_VALUE (type), 1));
11614 return dependent_type_p (type);
11617 if (TREE_CODE (expression) == SCOPE_REF
11618 && dependent_scope_ref_p (expression,
11619 type_dependent_expression_p))
11622 if (TREE_CODE (expression) == FUNCTION_DECL
11623 && DECL_LANG_SPECIFIC (expression)
11624 && DECL_TEMPLATE_INFO (expression)
11625 && (any_dependent_template_arguments_p
11626 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
11629 if (TREE_TYPE (expression) == unknown_type_node)
11631 if (TREE_CODE (expression) == ADDR_EXPR)
11632 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
11633 if (TREE_CODE (expression) == COMPONENT_REF)
11635 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
11637 expression = TREE_OPERAND (expression, 1);
11638 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11642 if (TREE_CODE (expression) == BASELINK)
11643 expression = BASELINK_FUNCTIONS (expression);
11644 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
11646 if (any_dependent_template_arguments_p
11647 (TREE_OPERAND (expression, 1)))
11649 expression = TREE_OPERAND (expression, 0);
11651 if (TREE_CODE (expression) == OVERLOAD)
11655 if (type_dependent_expression_p (OVL_CURRENT (expression)))
11657 expression = OVL_NEXT (expression);
11664 return (dependent_type_p (TREE_TYPE (expression)));
11667 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
11668 contains a type-dependent expression. */
11671 any_type_dependent_arguments_p (tree args)
11675 tree arg = TREE_VALUE (args);
11677 if (type_dependent_expression_p (arg))
11679 args = TREE_CHAIN (args);
11684 /* Returns TRUE if the ARG (a template argument) is dependent. */
11687 dependent_template_arg_p (tree arg)
11689 if (!processing_template_decl)
11692 if (TREE_CODE (arg) == TEMPLATE_DECL
11693 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11694 return dependent_template_p (arg);
11695 else if (TYPE_P (arg))
11696 return dependent_type_p (arg);
11698 return (type_dependent_expression_p (arg)
11699 || value_dependent_expression_p (arg));
11702 /* Returns true if ARGS (a collection of template arguments) contains
11703 any dependent arguments. */
11706 any_dependent_template_arguments_p (tree args)
11713 for (i = 0; i < TREE_VEC_LENGTH (args); ++i)
11714 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
11720 /* Returns TRUE if the template TMPL is dependent. */
11723 dependent_template_p (tree tmpl)
11725 /* Template template parameters are dependent. */
11726 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
11727 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
11729 /* So are qualified names that have not been looked up. */
11730 if (TREE_CODE (tmpl) == SCOPE_REF)
11732 /* So are member templates of dependent classes. */
11733 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
11734 return dependent_type_p (DECL_CONTEXT (tmpl));
11738 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
11741 dependent_template_id_p (tree tmpl, tree args)
11743 return (dependent_template_p (tmpl)
11744 || any_dependent_template_arguments_p (args));
11747 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
11748 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
11749 can be found. Note that this function peers inside uninstantiated
11750 templates and therefore should be used only in extremely limited
11754 resolve_typename_type (tree type, bool only_current_p)
11761 my_friendly_assert (TREE_CODE (type) == TYPENAME_TYPE,
11764 scope = TYPE_CONTEXT (type);
11765 name = TYPE_IDENTIFIER (type);
11767 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
11768 it first before we can figure out what NAME refers to. */
11769 if (TREE_CODE (scope) == TYPENAME_TYPE)
11770 scope = resolve_typename_type (scope, only_current_p);
11771 /* If we don't know what SCOPE refers to, then we cannot resolve the
11773 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
11774 return error_mark_node;
11775 /* If the SCOPE is a template type parameter, we have no way of
11776 resolving the name. */
11777 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
11779 /* If the SCOPE is not the current instantiation, there's no reason
11780 to look inside it. */
11781 if (only_current_p && !currently_open_class (scope))
11782 return error_mark_node;
11783 /* If SCOPE is a partial instantiation, it will not have a valid
11784 TYPE_FIELDS list, so use the original template. */
11785 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
11786 /* Enter the SCOPE so that name lookup will be resolved as if we
11787 were in the class definition. In particular, SCOPE will no
11788 longer be considered a dependent type. */
11789 push_scope (scope);
11790 /* Look up the declaration. */
11791 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
11792 /* Obtain the set of qualifiers applied to the TYPE. */
11793 quals = cp_type_quals (type);
11794 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
11795 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
11797 type = error_mark_node;
11798 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
11799 && TREE_CODE (decl) == TYPE_DECL)
11800 type = TREE_TYPE (decl);
11801 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
11802 && DECL_CLASS_TEMPLATE_P (decl))
11806 /* Obtain the template and the arguments. */
11807 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
11808 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
11809 /* Instantiate the template. */
11810 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
11811 /*entering_scope=*/0, tf_error | tf_user);
11814 type = error_mark_node;
11815 /* Qualify the resulting type. */
11816 if (type != error_mark_node && quals)
11817 type = cp_build_qualified_type (type, quals);
11818 /* Leave the SCOPE. */
11824 /* EXPR is an expression which is not type-dependent. Return a proxy
11825 for EXPR that can be used to compute the types of larger
11826 expressions containing EXPR. */
11829 build_non_dependent_expr (tree expr)
11831 /* Preserve null pointer constants so that the type of things like
11832 "p == 0" where "p" is a pointer can be determined. */
11833 if (null_ptr_cst_p (expr))
11835 /* Preserve OVERLOADs; the functions must be available to resolve
11837 if (TREE_CODE (expr) == OVERLOAD)
11839 /* Preserve string constants; conversions from string constants to
11840 "char *" are allowed, even though normally a "const char *"
11841 cannot be used to initialize a "char *". */
11842 if (TREE_CODE (expr) == STRING_CST)
11845 if (TREE_CODE (expr) == COND_EXPR)
11846 return build (COND_EXPR,
11848 TREE_OPERAND (expr, 0),
11849 build_non_dependent_expr (TREE_OPERAND (expr, 1)),
11850 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
11851 if (TREE_CODE (expr) == COMPOUND_EXPR
11852 && !COMPOUND_EXPR_OVERLOADED (expr))
11853 return build (COMPOUND_EXPR,
11855 TREE_OPERAND (expr, 0),
11856 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
11858 /* Otherwise, build a NON_DEPENDENT_EXPR.
11860 REFERENCE_TYPEs are not stripped for expressions in templates
11861 because doing so would play havoc with mangling. Consider, for
11864 template <typename T> void f<T& g>() { g(); }
11866 In the body of "f", the expression for "g" will have
11867 REFERENCE_TYPE, even though the standard says that it should
11868 not. The reason is that we must preserve the syntactic form of
11869 the expression so that mangling (say) "f<g>" inside the body of
11870 "f" works out correctly. Therefore, the REFERENCE_TYPE is
11872 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
11875 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
11876 Return a new TREE_LIST with the various arguments replaced with
11877 equivalent non-dependent expressions. */
11880 build_non_dependent_args (tree args)
11885 new_args = NULL_TREE;
11886 for (a = args; a; a = TREE_CHAIN (a))
11887 new_args = tree_cons (NULL_TREE,
11888 build_non_dependent_expr (TREE_VALUE (a)),
11890 return nreverse (new_args);
11893 #include "gt-cp-pt.h"