1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
38 #include "tree-inline.h"
45 #include "tree-iterator.h"
47 /* The type of functions taking a tree, and some additional data, and
49 typedef int (*tree_fn_t) (tree, void*);
51 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
52 instantiations have been deferred, either because their definitions
53 were not yet available, or because we were putting off doing the work.
54 The TREE_PURPOSE of each entry is either a DECL (for a function or
55 static data member), or a TYPE (for a class) indicating what we are
56 hoping to instantiate. The TREE_VALUE is not used. */
57 static GTY(()) tree pending_templates;
58 static GTY(()) tree last_pending_template;
60 int processing_template_parmlist;
61 static int template_header_count;
63 static GTY(()) tree saved_trees;
64 static GTY(()) varray_type inline_parm_levels;
65 static size_t inline_parm_levels_used;
67 static GTY(()) tree current_tinst_level;
69 static GTY(()) tree saved_access_scope;
71 /* Live only within one (recursive) call to tsubst_expr. We use
72 this to pass the statement expression node from the STMT_EXPR
73 to the EXPR_STMT that is its result. */
74 static tree cur_stmt_expr;
76 /* A map from local variable declarations in the body of the template
77 presently being instantiated to the corresponding instantiated
79 static htab_t local_specializations;
81 #define UNIFY_ALLOW_NONE 0
82 #define UNIFY_ALLOW_MORE_CV_QUAL 1
83 #define UNIFY_ALLOW_LESS_CV_QUAL 2
84 #define UNIFY_ALLOW_DERIVED 4
85 #define UNIFY_ALLOW_INTEGER 8
86 #define UNIFY_ALLOW_OUTER_LEVEL 16
87 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
88 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
89 #define UNIFY_ALLOW_MAX_CORRECTION 128
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*,
118 struct pointer_set_t*);
119 static tree build_template_parm_index (int, int, int, tree, tree);
120 static int inline_needs_template_parms (tree);
121 static void push_inline_template_parms_recursive (tree, int);
122 static tree retrieve_local_specialization (tree);
123 static void register_local_specialization (tree, tree);
124 static tree reduce_template_parm_level (tree, tree, int);
125 static int mark_template_parm (tree, void *);
126 static int template_parm_this_level_p (tree, void *);
127 static tree tsubst_friend_function (tree, tree);
128 static tree tsubst_friend_class (tree, tree);
129 static int can_complete_type_without_circularity (tree);
130 static tree get_bindings (tree, tree, tree);
131 static tree get_bindings_real (tree, tree, tree, int, int, int);
132 static int template_decl_level (tree);
133 static int check_cv_quals_for_unify (int, tree, tree);
134 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
135 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
136 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
137 static void regenerate_decl_from_template (tree, tree);
138 static tree most_specialized (tree, tree, tree);
139 static tree most_specialized_class (tree, tree);
140 static int template_class_depth_real (tree, int);
141 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
142 static tree tsubst_decl (tree, tree, tree, tsubst_flags_t);
143 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
144 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
145 static void check_specialization_scope (void);
146 static tree process_partial_specialization (tree);
147 static void set_current_access_from_decl (tree);
148 static void check_default_tmpl_args (tree, tree, int, int);
149 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
150 static tree get_template_base (tree, tree, tree, tree);
151 static int verify_class_unification (tree, tree, tree);
152 static tree try_class_unification (tree, tree, tree, tree);
153 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
155 static tree determine_specialization (tree, tree, tree *, int, int);
156 static int template_args_equal (tree, tree);
157 static void tsubst_default_arguments (tree);
158 static tree for_each_template_parm_r (tree *, int *, void *);
159 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
160 static void copy_default_args_to_explicit_spec (tree);
161 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
162 static int eq_local_specializations (const void *, const void *);
163 static bool dependent_type_p_r (tree);
164 static tree tsubst (tree, tree, tsubst_flags_t, tree);
165 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
166 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
168 /* Make the current scope suitable for access checking when we are
169 processing T. T can be FUNCTION_DECL for instantiated function
170 template, or VAR_DECL for static member variable (need by
171 instantiate_decl). */
174 push_access_scope (tree t)
176 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
177 || TREE_CODE (t) == VAR_DECL);
179 if (DECL_CLASS_SCOPE_P (t))
180 push_nested_class (DECL_CONTEXT (t));
182 push_to_top_level ();
184 if (TREE_CODE (t) == FUNCTION_DECL)
186 saved_access_scope = tree_cons
187 (NULL_TREE, current_function_decl, saved_access_scope);
188 current_function_decl = t;
192 /* Restore the scope set up by push_access_scope. T is the node we
196 pop_access_scope (tree t)
198 if (TREE_CODE (t) == FUNCTION_DECL)
200 current_function_decl = TREE_VALUE (saved_access_scope);
201 saved_access_scope = TREE_CHAIN (saved_access_scope);
204 if (DECL_CLASS_SCOPE_P (t))
207 pop_from_top_level ();
210 /* Do any processing required when DECL (a member template
211 declaration) is finished. Returns the TEMPLATE_DECL corresponding
212 to DECL, unless it is a specialization, in which case the DECL
213 itself is returned. */
216 finish_member_template_decl (tree decl)
218 if (decl == error_mark_node)
219 return error_mark_node;
221 gcc_assert (DECL_P (decl));
223 if (TREE_CODE (decl) == TYPE_DECL)
227 type = TREE_TYPE (decl);
228 if (IS_AGGR_TYPE (type)
229 && CLASSTYPE_TEMPLATE_INFO (type)
230 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
232 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
233 check_member_template (tmpl);
238 else if (TREE_CODE (decl) == FIELD_DECL)
239 error ("data member %qD cannot be a member template", decl);
240 else if (DECL_TEMPLATE_INFO (decl))
242 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
244 check_member_template (DECL_TI_TEMPLATE (decl));
245 return DECL_TI_TEMPLATE (decl);
251 error ("invalid member template declaration %qD", decl);
253 return error_mark_node;
256 /* Returns the template nesting level of the indicated class TYPE.
266 A<T>::B<U> has depth two, while A<T> has depth one.
267 Both A<T>::B<int> and A<int>::B<U> have depth one, if
268 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
271 This function is guaranteed to return 0 if passed NULL_TREE so
272 that, for example, `template_class_depth (current_class_type)' is
276 template_class_depth_real (tree type, int count_specializations)
281 type && TREE_CODE (type) != NAMESPACE_DECL;
282 type = (TREE_CODE (type) == FUNCTION_DECL)
283 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
285 if (TREE_CODE (type) != FUNCTION_DECL)
287 if (CLASSTYPE_TEMPLATE_INFO (type)
288 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
289 && ((count_specializations
290 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
291 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
296 if (DECL_TEMPLATE_INFO (type)
297 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
298 && ((count_specializations
299 && DECL_TEMPLATE_SPECIALIZATION (type))
300 || uses_template_parms (DECL_TI_ARGS (type))))
308 /* Returns the template nesting level of the indicated class TYPE.
309 Like template_class_depth_real, but instantiations do not count in
313 template_class_depth (tree type)
315 return template_class_depth_real (type, /*count_specializations=*/0);
318 /* Returns 1 if processing DECL as part of do_pending_inlines
319 needs us to push template parms. */
322 inline_needs_template_parms (tree decl)
324 if (! DECL_TEMPLATE_INFO (decl))
327 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
328 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
331 /* Subroutine of maybe_begin_member_template_processing.
332 Push the template parms in PARMS, starting from LEVELS steps into the
333 chain, and ending at the beginning, since template parms are listed
337 push_inline_template_parms_recursive (tree parmlist, int levels)
339 tree parms = TREE_VALUE (parmlist);
343 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
345 ++processing_template_decl;
346 current_template_parms
347 = tree_cons (size_int (processing_template_decl),
348 parms, current_template_parms);
349 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
351 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
353 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
355 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
356 gcc_assert (DECL_P (parm));
358 switch (TREE_CODE (parm))
367 /* Make a CONST_DECL as is done in process_template_parm.
368 It is ugly that we recreate this here; the original
369 version built in process_template_parm is no longer
371 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
373 DECL_ARTIFICIAL (decl) = 1;
374 TREE_CONSTANT (decl) = 1;
375 TREE_INVARIANT (decl) = 1;
376 TREE_READONLY (decl) = 1;
377 DECL_INITIAL (decl) = DECL_INITIAL (parm);
378 SET_DECL_TEMPLATE_PARM_P (decl);
389 /* Restore the template parameter context for a member template or
390 a friend template defined in a class definition. */
393 maybe_begin_member_template_processing (tree decl)
398 if (inline_needs_template_parms (decl))
400 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
401 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
403 if (DECL_TEMPLATE_SPECIALIZATION (decl))
406 parms = TREE_CHAIN (parms);
409 push_inline_template_parms_recursive (parms, levels);
412 /* Remember how many levels of template parameters we pushed so that
413 we can pop them later. */
414 if (!inline_parm_levels)
415 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
416 if (inline_parm_levels_used == inline_parm_levels->num_elements)
417 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
418 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
419 ++inline_parm_levels_used;
422 /* Undo the effects of begin_member_template_processing. */
425 maybe_end_member_template_processing (void)
429 if (!inline_parm_levels_used)
432 --inline_parm_levels_used;
434 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
437 --processing_template_decl;
438 current_template_parms = TREE_CHAIN (current_template_parms);
443 /* Return a new template argument vector which contains all of ARGS,
444 but has as its innermost set of arguments the EXTRA_ARGS. */
447 add_to_template_args (tree args, tree extra_args)
454 extra_depth = TMPL_ARGS_DEPTH (extra_args);
455 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
457 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
458 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
460 for (j = 1; j <= extra_depth; ++j, ++i)
461 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
466 /* Like add_to_template_args, but only the outermost ARGS are added to
467 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
468 (EXTRA_ARGS) levels are added. This function is used to combine
469 the template arguments from a partial instantiation with the
470 template arguments used to attain the full instantiation from the
471 partial instantiation. */
474 add_outermost_template_args (tree args, tree extra_args)
478 /* If there are more levels of EXTRA_ARGS than there are ARGS,
479 something very fishy is going on. */
480 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
482 /* If *all* the new arguments will be the EXTRA_ARGS, just return
484 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
487 /* For the moment, we make ARGS look like it contains fewer levels. */
488 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
490 new_args = add_to_template_args (args, extra_args);
492 /* Now, we restore ARGS to its full dimensions. */
493 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
498 /* Return the N levels of innermost template arguments from the ARGS. */
501 get_innermost_template_args (tree args, int n)
509 /* If N is 1, just return the innermost set of template arguments. */
511 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
513 /* If we're not removing anything, just return the arguments we were
515 extra_levels = TMPL_ARGS_DEPTH (args) - n;
516 gcc_assert (extra_levels >= 0);
517 if (extra_levels == 0)
520 /* Make a new set of arguments, not containing the outer arguments. */
521 new_args = make_tree_vec (n);
522 for (i = 1; i <= n; ++i)
523 SET_TMPL_ARGS_LEVEL (new_args, i,
524 TMPL_ARGS_LEVEL (args, i + extra_levels));
529 /* We've got a template header coming up; push to a new level for storing
533 begin_template_parm_list (void)
535 /* We use a non-tag-transparent scope here, which causes pushtag to
536 put tags in this scope, rather than in the enclosing class or
537 namespace scope. This is the right thing, since we want
538 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
539 global template class, push_template_decl handles putting the
540 TEMPLATE_DECL into top-level scope. For a nested template class,
543 template <class T> struct S1 {
544 template <class T> struct S2 {};
547 pushtag contains special code to call pushdecl_with_scope on the
548 TEMPLATE_DECL for S2. */
549 begin_scope (sk_template_parms, NULL);
550 ++processing_template_decl;
551 ++processing_template_parmlist;
552 note_template_header (0);
555 /* This routine is called when a specialization is declared. If it is
556 invalid to declare a specialization here, an error is reported. */
559 check_specialization_scope (void)
561 tree scope = current_scope ();
565 An explicit specialization shall be declared in the namespace of
566 which the template is a member, or, for member templates, in the
567 namespace of which the enclosing class or enclosing class
568 template is a member. An explicit specialization of a member
569 function, member class or static data member of a class template
570 shall be declared in the namespace of which the class template
572 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
573 error ("explicit specialization in non-namespace scope %qD", scope);
577 In an explicit specialization declaration for a member of a class
578 template or a member template that appears in namespace scope,
579 the member template and some of its enclosing class templates may
580 remain unspecialized, except that the declaration shall not
581 explicitly specialize a class member template if its enclosing
582 class templates are not explicitly specialized as well. */
583 if (current_template_parms)
584 error ("enclosing class templates are not explicitly specialized");
587 /* We've just seen template <>. */
590 begin_specialization (void)
592 begin_scope (sk_template_spec, NULL);
593 note_template_header (1);
594 check_specialization_scope ();
597 /* Called at then end of processing a declaration preceded by
601 end_specialization (void)
604 reset_specialization ();
607 /* Any template <>'s that we have seen thus far are not referring to a
608 function specialization. */
611 reset_specialization (void)
613 processing_specialization = 0;
614 template_header_count = 0;
617 /* We've just seen a template header. If SPECIALIZATION is nonzero,
618 it was of the form template <>. */
621 note_template_header (int specialization)
623 processing_specialization = specialization;
624 template_header_count++;
627 /* We're beginning an explicit instantiation. */
630 begin_explicit_instantiation (void)
632 gcc_assert (!processing_explicit_instantiation);
633 processing_explicit_instantiation = true;
638 end_explicit_instantiation (void)
640 gcc_assert (processing_explicit_instantiation);
641 processing_explicit_instantiation = false;
644 /* A explicit specialization or partial specialization TMPL is being
645 declared. Check that the namespace in which the specialization is
646 occurring is permissible. Returns false iff it is invalid to
647 specialize TMPL in the current namespace. */
650 check_specialization_namespace (tree tmpl)
652 tree tpl_ns = decl_namespace_context (tmpl);
656 An explicit specialization shall be declared in the namespace of
657 which the template is a member, or, for member templates, in the
658 namespace of which the enclosing class or enclosing class
659 template is a member. An explicit specialization of a member
660 function, member class or static data member of a class template
661 shall be declared in the namespace of which the class template is
663 if (is_associated_namespace (current_namespace, tpl_ns))
664 /* Same or super-using namespace. */
668 pedwarn ("specialization of %qD in different namespace", tmpl);
669 cp_pedwarn_at (" from definition of %q#D", tmpl);
674 /* The TYPE is being declared. If it is a template type, that means it
675 is a partial specialization. Do appropriate error-checking. */
678 maybe_process_partial_specialization (tree type)
680 /* TYPE maybe an ERROR_MARK_NODE. */
681 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
683 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
685 /* This is for ordinary explicit specialization and partial
686 specialization of a template class such as:
688 template <> class C<int>;
692 template <class T> class C<T*>;
694 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
696 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
697 && !COMPLETE_TYPE_P (type))
699 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
700 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
701 if (processing_template_decl)
702 push_template_decl (TYPE_MAIN_DECL (type));
704 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
705 error ("specialization of %qT after instantiation", type);
707 else if (CLASS_TYPE_P (type)
708 && !CLASSTYPE_USE_TEMPLATE (type)
709 && CLASSTYPE_TEMPLATE_INFO (type)
710 && context && CLASS_TYPE_P (context)
711 && CLASSTYPE_TEMPLATE_INFO (context))
713 /* This is for an explicit specialization of member class
714 template according to [temp.expl.spec/18]:
716 template <> template <class U> class C<int>::D;
718 The context `C<int>' must be an implicit instantiation.
719 Otherwise this is just a member class template declared
722 template <> class C<int> { template <class U> class D; };
723 template <> template <class U> class C<int>::D;
725 In the first case, `C<int>::D' is a specialization of `C<T>::D'
726 while in the second case, `C<int>::D' is a primary template
727 and `C<T>::D' may not exist. */
729 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
730 && !COMPLETE_TYPE_P (type))
734 if (current_namespace
735 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
737 pedwarn ("specializing %q#T in different namespace", type);
738 cp_pedwarn_at (" from definition of %q#D",
739 CLASSTYPE_TI_TEMPLATE (type));
742 /* Check for invalid specialization after instantiation:
744 template <> template <> class C<int>::D<int>;
745 template <> template <class U> class C<int>::D; */
747 for (t = DECL_TEMPLATE_INSTANTIATIONS
748 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
749 t; t = TREE_CHAIN (t))
750 if (TREE_VALUE (t) != type
751 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
752 error ("specialization %qT after instantiation %qT",
753 type, TREE_VALUE (t));
755 /* Mark TYPE as a specialization. And as a result, we only
756 have one level of template argument for the innermost
758 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
759 CLASSTYPE_TI_ARGS (type)
760 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
763 else if (processing_specialization)
764 error ("explicit specialization of non-template %qT", type);
767 /* Returns nonzero if we can optimize the retrieval of specializations
768 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
769 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
772 optimize_specialization_lookup_p (tree tmpl)
774 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
775 && DECL_CLASS_SCOPE_P (tmpl)
776 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
778 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
779 /* The optimized lookup depends on the fact that the
780 template arguments for the member function template apply
781 purely to the containing class, which is not true if the
782 containing class is an explicit or partial
784 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
785 && !DECL_MEMBER_TEMPLATE_P (tmpl)
786 && !DECL_CONV_FN_P (tmpl)
787 /* It is possible to have a template that is not a member
788 template and is not a member of a template class:
790 template <typename T>
791 struct S { friend A::f(); };
793 Here, the friend function is a template, but the context does
794 not have template information. The optimized lookup relies
795 on having ARGS be the template arguments for both the class
796 and the function template. */
797 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
800 /* Retrieve the specialization (in the sense of [temp.spec] - a
801 specialization is either an instantiation or an explicit
802 specialization) of TMPL for the given template ARGS. If there is
803 no such specialization, return NULL_TREE. The ARGS are a vector of
804 arguments, or a vector of vectors of arguments, in the case of
805 templates with more than one level of parameters.
807 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
808 then we search for a partial specialization matching ARGS. This
809 parameter is ignored if TMPL is not a class template. */
812 retrieve_specialization (tree tmpl, tree args,
813 bool class_specializations_p)
815 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
817 /* There should be as many levels of arguments as there are
818 levels of parameters. */
819 gcc_assert (TMPL_ARGS_DEPTH (args)
820 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
822 if (optimize_specialization_lookup_p (tmpl))
825 tree class_specialization;
830 /* The template arguments actually apply to the containing
831 class. Find the class specialization with those
833 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
835 = retrieve_specialization (class_template, args,
836 /*class_specializations_p=*/false);
837 if (!class_specialization)
839 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
840 for the specialization. */
841 idx = class_method_index_for_fn (class_specialization, tmpl);
844 /* Iterate through the methods with the indicated name, looking
845 for the one that has an instance of TMPL. */
846 methods = CLASSTYPE_METHOD_VEC (class_specialization);
847 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
849 tree fn = OVL_CURRENT (fns);
850 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
860 /* Class templates store their instantiations on the
861 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
862 DECL_TEMPLATE_SPECIALIZATIONS list. */
863 if (!class_specializations_p
864 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
865 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
867 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
869 /* Iterate through the list until we find a matching template. */
870 while (*sp != NULL_TREE)
874 if (comp_template_args (TREE_PURPOSE (spec), args))
876 /* Use the move-to-front heuristic to speed up future
880 *sp = TREE_CHAIN (*sp);
881 TREE_CHAIN (spec) = *head;
884 return TREE_VALUE (spec);
886 sp = &TREE_CHAIN (spec);
893 /* Like retrieve_specialization, but for local declarations. */
896 retrieve_local_specialization (tree tmpl)
898 tree spec = htab_find_with_hash (local_specializations, tmpl,
899 htab_hash_pointer (tmpl));
900 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
903 /* Returns nonzero iff DECL is a specialization of TMPL. */
906 is_specialization_of (tree decl, tree tmpl)
910 if (TREE_CODE (decl) == FUNCTION_DECL)
914 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
920 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
922 for (t = TREE_TYPE (decl);
924 t = CLASSTYPE_USE_TEMPLATE (t)
925 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
926 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
933 /* Returns nonzero iff DECL is a specialization of friend declaration
934 FRIEND according to [temp.friend]. */
937 is_specialization_of_friend (tree decl, tree friend)
939 bool need_template = true;
942 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
943 || TREE_CODE (decl) == TYPE_DECL);
945 /* For [temp.friend/6] when FRIEND is an ordinary member function
946 of a template class, we want to check if DECL is a specialization
948 if (TREE_CODE (friend) == FUNCTION_DECL
949 && DECL_TEMPLATE_INFO (friend)
950 && !DECL_USE_TEMPLATE (friend))
952 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
953 friend = DECL_TI_TEMPLATE (friend);
954 need_template = false;
956 else if (TREE_CODE (friend) == TEMPLATE_DECL
957 && !PRIMARY_TEMPLATE_P (friend))
958 need_template = false;
960 /* There is nothing to do if this is not a template friend. */
961 if (TREE_CODE (friend) != TEMPLATE_DECL)
964 if (is_specialization_of (decl, friend))
968 A member of a class template may be declared to be a friend of a
969 non-template class. In this case, the corresponding member of
970 every specialization of the class template is a friend of the
971 class granting friendship.
973 For example, given a template friend declaration
975 template <class T> friend void A<T>::f();
977 the member function below is considered a friend
979 template <> struct A<int> {
983 For this type of template friend, TEMPLATE_DEPTH below will be
984 nonzero. To determine if DECL is a friend of FRIEND, we first
985 check if the enclosing class is a specialization of another. */
987 template_depth = template_class_depth (DECL_CONTEXT (friend));
989 && DECL_CLASS_SCOPE_P (decl)
990 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
991 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
993 /* Next, we check the members themselves. In order to handle
994 a few tricky cases, such as when FRIEND's are
996 template <class T> friend void A<T>::g(T t);
997 template <class T> template <T t> friend void A<T>::h();
1001 void A<int>::g(int);
1002 template <int> void A<int>::h();
1004 we need to figure out ARGS, the template arguments from
1005 the context of DECL. This is required for template substitution
1006 of `T' in the function parameter of `g' and template parameter
1007 of `h' in the above examples. Here ARGS corresponds to `int'. */
1009 tree context = DECL_CONTEXT (decl);
1010 tree args = NULL_TREE;
1011 int current_depth = 0;
1013 while (current_depth < template_depth)
1015 if (CLASSTYPE_TEMPLATE_INFO (context))
1017 if (current_depth == 0)
1018 args = TYPE_TI_ARGS (context);
1020 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1023 context = TYPE_CONTEXT (context);
1026 if (TREE_CODE (decl) == FUNCTION_DECL)
1031 tree friend_args_type;
1032 tree decl_args_type;
1034 /* Make sure that both DECL and FRIEND are templates or
1036 is_template = DECL_TEMPLATE_INFO (decl)
1037 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1038 if (need_template ^ is_template)
1040 else if (is_template)
1042 /* If both are templates, check template parameter list. */
1044 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1046 if (!comp_template_parms
1047 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1051 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1054 decl_type = TREE_TYPE (decl);
1056 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1057 tf_none, NULL_TREE);
1058 if (friend_type == error_mark_node)
1061 /* Check if return types match. */
1062 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1065 /* Check if function parameter types match, ignoring the
1066 `this' parameter. */
1067 friend_args_type = TYPE_ARG_TYPES (friend_type);
1068 decl_args_type = TYPE_ARG_TYPES (decl_type);
1069 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1070 friend_args_type = TREE_CHAIN (friend_args_type);
1071 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1072 decl_args_type = TREE_CHAIN (decl_args_type);
1074 return compparms (decl_args_type, friend_args_type);
1078 /* DECL is a TYPE_DECL */
1080 tree decl_type = TREE_TYPE (decl);
1082 /* Make sure that both DECL and FRIEND are templates or
1085 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1086 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1088 if (need_template ^ is_template)
1090 else if (is_template)
1093 /* If both are templates, check the name of the two
1094 TEMPLATE_DECL's first because is_friend didn't. */
1095 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1096 != DECL_NAME (friend))
1099 /* Now check template parameter list. */
1101 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1103 return comp_template_parms
1104 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1108 return (DECL_NAME (decl)
1109 == DECL_NAME (friend));
1115 /* Register the specialization SPEC as a specialization of TMPL with
1116 the indicated ARGS. Returns SPEC, or an equivalent prior
1117 declaration, if available. */
1120 register_specialization (tree spec, tree tmpl, tree args)
1124 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1126 if (TREE_CODE (spec) == FUNCTION_DECL
1127 && uses_template_parms (DECL_TI_ARGS (spec)))
1128 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1129 register it; we want the corresponding TEMPLATE_DECL instead.
1130 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1131 the more obvious `uses_template_parms (spec)' to avoid problems
1132 with default function arguments. In particular, given
1133 something like this:
1135 template <class T> void f(T t1, T t = T())
1137 the default argument expression is not substituted for in an
1138 instantiation unless and until it is actually needed. */
1141 /* There should be as many levels of arguments as there are
1142 levels of parameters. */
1143 gcc_assert (TMPL_ARGS_DEPTH (args)
1144 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
1146 fn = retrieve_specialization (tmpl, args,
1147 /*class_specializations_p=*/false);
1148 /* We can sometimes try to re-register a specialization that we've
1149 already got. In particular, regenerate_decl_from_template calls
1150 duplicate_decls which will update the specialization list. But,
1151 we'll still get called again here anyhow. It's more convenient
1152 to simply allow this than to try to prevent it. */
1155 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1157 if (DECL_TEMPLATE_INSTANTIATION (fn))
1160 || DECL_EXPLICIT_INSTANTIATION (fn))
1162 error ("specialization of %qD after instantiation",
1168 /* This situation should occur only if the first
1169 specialization is an implicit instantiation, the
1170 second is an explicit specialization, and the
1171 implicit instantiation has not yet been used. That
1172 situation can occur if we have implicitly
1173 instantiated a member function and then specialized
1176 We can also wind up here if a friend declaration that
1177 looked like an instantiation turns out to be a
1180 template <class T> void foo(T);
1181 class S { friend void foo<>(int) };
1182 template <> void foo(int);
1184 We transform the existing DECL in place so that any
1185 pointers to it become pointers to the updated
1188 If there was a definition for the template, but not
1189 for the specialization, we want this to look as if
1190 there were no definition, and vice versa. */
1191 DECL_INITIAL (fn) = NULL_TREE;
1192 duplicate_decls (spec, fn);
1197 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1199 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
1200 /* Dup decl failed, but this is a new definition. Set the
1201 line number so any errors match this new
1203 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1209 /* A specialization must be declared in the same namespace as the
1210 template it is specializing. */
1211 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1212 && !check_specialization_namespace (tmpl))
1213 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1215 if (!optimize_specialization_lookup_p (tmpl))
1216 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1217 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1222 /* Unregister the specialization SPEC as a specialization of TMPL.
1223 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1224 if the SPEC was listed as a specialization of TMPL. */
1227 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1231 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1233 s = &TREE_CHAIN (*s))
1234 if (TREE_VALUE (*s) == spec)
1237 *s = TREE_CHAIN (*s);
1239 TREE_VALUE (*s) = new_spec;
1246 /* Compare an entry in the local specializations hash table P1 (which
1247 is really a pointer to a TREE_LIST) with P2 (which is really a
1251 eq_local_specializations (const void *p1, const void *p2)
1253 return TREE_VALUE ((tree) p1) == (tree) p2;
1256 /* Hash P1, an entry in the local specializations table. */
1259 hash_local_specialization (const void* p1)
1261 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1264 /* Like register_specialization, but for local declarations. We are
1265 registering SPEC, an instantiation of TMPL. */
1268 register_local_specialization (tree spec, tree tmpl)
1272 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1273 htab_hash_pointer (tmpl), INSERT);
1274 *slot = build_tree_list (spec, tmpl);
1277 /* Print the list of candidate FNS in an error message. */
1280 print_candidates (tree fns)
1284 const char *str = "candidates are:";
1286 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1290 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1291 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
1296 /* Returns the template (one of the functions given by TEMPLATE_ID)
1297 which can be specialized to match the indicated DECL with the
1298 explicit template args given in TEMPLATE_ID. The DECL may be
1299 NULL_TREE if none is available. In that case, the functions in
1300 TEMPLATE_ID are non-members.
1302 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1303 specialization of a member template.
1305 The TEMPLATE_COUNT is the number of references to qualifying
1306 template classes that appeared in the name of the function. See
1307 check_explicit_specialization for a more accurate description.
1309 The template args (those explicitly specified and those deduced)
1310 are output in a newly created vector *TARGS_OUT.
1312 If it is impossible to determine the result, an error message is
1313 issued. The error_mark_node is returned to indicate failure. */
1316 determine_specialization (tree template_id,
1319 int need_member_template,
1324 tree explicit_targs;
1325 tree candidates = NULL_TREE;
1326 tree templates = NULL_TREE;
1328 struct cp_binding_level *b;
1330 *targs_out = NULL_TREE;
1332 if (template_id == error_mark_node)
1333 return error_mark_node;
1335 fns = TREE_OPERAND (template_id, 0);
1336 explicit_targs = TREE_OPERAND (template_id, 1);
1338 if (fns == error_mark_node)
1339 return error_mark_node;
1341 /* Check for baselinks. */
1342 if (BASELINK_P (fns))
1343 fns = BASELINK_FUNCTIONS (fns);
1345 if (!is_overloaded_fn (fns))
1347 error ("%qD is not a function template", fns);
1348 return error_mark_node;
1351 /* Count the number of template headers specified for this
1354 for (b = current_binding_level;
1355 b->kind == sk_template_parms || b->kind == sk_template_spec;
1359 for (; fns; fns = OVL_NEXT (fns))
1361 tree fn = OVL_CURRENT (fns);
1363 if (TREE_CODE (fn) == TEMPLATE_DECL)
1365 tree decl_arg_types;
1368 /* DECL might be a specialization of FN. */
1370 /* Adjust the type of DECL in case FN is a static member. */
1371 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1372 if (DECL_STATIC_FUNCTION_P (fn)
1373 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1374 decl_arg_types = TREE_CHAIN (decl_arg_types);
1376 /* Check that the number of function parameters matches.
1378 template <class T> void f(int i = 0);
1379 template <> void f<int>();
1380 The specialization f<int> is invalid but is not caught
1381 by get_bindings below. */
1383 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1384 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1387 /* For a non-static member function, we need to make sure that
1388 the const qualification is the same. This can be done by
1389 checking the 'this' in the argument list. */
1390 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1391 && !same_type_p (TREE_VALUE (fn_arg_types),
1392 TREE_VALUE (decl_arg_types)))
1395 /* In case of explicit specialization, we need to check if
1396 the number of template headers appearing in the specialization
1397 is correct. This is usually done in check_explicit_specialization,
1398 but the check done there cannot be exhaustive when specializing
1399 member functions. Consider the following code:
1401 template <> void A<int>::f(int);
1402 template <> template <> void A<int>::f(int);
1404 Assuming that A<int> is not itself an explicit specialization
1405 already, the first line specializes "f" which is a non-template
1406 member function, whilst the second line specializes "f" which
1407 is a template member function. So both lines are syntactically
1408 correct, and check_explicit_specialization does not reject
1411 Here, we can do better, as we are matching the specialization
1412 against the declarations. We count the number of template
1413 headers, and we check if they match TEMPLATE_COUNT + 1
1414 (TEMPLATE_COUNT is the number of qualifying template classes,
1415 plus there must be another header for the member template
1418 Notice that if header_count is zero, this is not a
1419 specialization but rather a template instantiation, so there
1420 is no check we can perform here. */
1421 if (header_count && header_count != template_count + 1)
1424 /* See whether this function might be a specialization of this
1426 targs = get_bindings (fn, decl, explicit_targs);
1429 /* We cannot deduce template arguments that when used to
1430 specialize TMPL will produce DECL. */
1433 /* Save this template, and the arguments deduced. */
1434 templates = tree_cons (targs, fn, templates);
1436 else if (need_member_template)
1437 /* FN is an ordinary member function, and we need a
1438 specialization of a member template. */
1440 else if (TREE_CODE (fn) != FUNCTION_DECL)
1441 /* We can get IDENTIFIER_NODEs here in certain erroneous
1444 else if (!DECL_FUNCTION_MEMBER_P (fn))
1445 /* This is just an ordinary non-member function. Nothing can
1446 be a specialization of that. */
1448 else if (DECL_ARTIFICIAL (fn))
1449 /* Cannot specialize functions that are created implicitly. */
1453 tree decl_arg_types;
1455 /* This is an ordinary member function. However, since
1456 we're here, we can assume it's enclosing class is a
1457 template class. For example,
1459 template <typename T> struct S { void f(); };
1460 template <> void S<int>::f() {}
1462 Here, S<int>::f is a non-template, but S<int> is a
1463 template class. If FN has the same type as DECL, we
1464 might be in business. */
1466 if (!DECL_TEMPLATE_INFO (fn))
1467 /* Its enclosing class is an explicit specialization
1468 of a template class. This is not a candidate. */
1471 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1472 TREE_TYPE (TREE_TYPE (fn))))
1473 /* The return types differ. */
1476 /* Adjust the type of DECL in case FN is a static member. */
1477 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1478 if (DECL_STATIC_FUNCTION_P (fn)
1479 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1480 decl_arg_types = TREE_CHAIN (decl_arg_types);
1482 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1485 candidates = tree_cons (NULL_TREE, fn, candidates);
1489 if (templates && TREE_CHAIN (templates))
1495 It is possible for a specialization with a given function
1496 signature to be instantiated from more than one function
1497 template. In such cases, explicit specification of the
1498 template arguments must be used to uniquely identify the
1499 function template specialization being specialized.
1501 Note that here, there's no suggestion that we're supposed to
1502 determine which of the candidate templates is most
1503 specialized. However, we, also have:
1507 Partial ordering of overloaded function template
1508 declarations is used in the following contexts to select
1509 the function template to which a function template
1510 specialization refers:
1512 -- when an explicit specialization refers to a function
1515 So, we do use the partial ordering rules, at least for now.
1516 This extension can only serve to make invalid programs valid,
1517 so it's safe. And, there is strong anecdotal evidence that
1518 the committee intended the partial ordering rules to apply;
1519 the EDG front-end has that behavior, and John Spicer claims
1520 that the committee simply forgot to delete the wording in
1521 [temp.expl.spec]. */
1522 tree tmpl = most_specialized (templates, decl, explicit_targs);
1523 if (tmpl && tmpl != error_mark_node)
1525 targs = get_bindings (tmpl, decl, explicit_targs);
1526 templates = tree_cons (targs, tmpl, NULL_TREE);
1530 if (templates == NULL_TREE && candidates == NULL_TREE)
1532 cp_error_at ("template-id %qD for %q+D does not match any template "
1535 return error_mark_node;
1537 else if ((templates && TREE_CHAIN (templates))
1538 || (candidates && TREE_CHAIN (candidates))
1539 || (templates && candidates))
1541 cp_error_at ("ambiguous template specialization %qD for %q+D",
1543 chainon (candidates, templates);
1544 print_candidates (candidates);
1545 return error_mark_node;
1548 /* We have one, and exactly one, match. */
1551 /* It was a specialization of an ordinary member function in a
1553 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1554 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1557 /* It was a specialization of a template. */
1558 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1559 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1561 *targs_out = copy_node (targs);
1562 SET_TMPL_ARGS_LEVEL (*targs_out,
1563 TMPL_ARGS_DEPTH (*targs_out),
1564 TREE_PURPOSE (templates));
1567 *targs_out = TREE_PURPOSE (templates);
1568 return TREE_VALUE (templates);
1571 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1572 but with the default argument values filled in from those in the
1576 copy_default_args_to_explicit_spec_1 (tree spec_types,
1579 tree new_spec_types;
1584 if (spec_types == void_list_node)
1585 return void_list_node;
1587 /* Substitute into the rest of the list. */
1589 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1590 TREE_CHAIN (tmpl_types));
1592 /* Add the default argument for this parameter. */
1593 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1594 TREE_VALUE (spec_types),
1598 /* DECL is an explicit specialization. Replicate default arguments
1599 from the template it specializes. (That way, code like:
1601 template <class T> void f(T = 3);
1602 template <> void f(double);
1605 works, as required.) An alternative approach would be to look up
1606 the correct default arguments at the call-site, but this approach
1607 is consistent with how implicit instantiations are handled. */
1610 copy_default_args_to_explicit_spec (tree decl)
1615 tree new_spec_types;
1619 tree object_type = NULL_TREE;
1620 tree in_charge = NULL_TREE;
1621 tree vtt = NULL_TREE;
1623 /* See if there's anything we need to do. */
1624 tmpl = DECL_TI_TEMPLATE (decl);
1625 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1626 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1627 if (TREE_PURPOSE (t))
1632 old_type = TREE_TYPE (decl);
1633 spec_types = TYPE_ARG_TYPES (old_type);
1635 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1637 /* Remove the this pointer, but remember the object's type for
1639 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1640 spec_types = TREE_CHAIN (spec_types);
1641 tmpl_types = TREE_CHAIN (tmpl_types);
1643 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1645 /* DECL may contain more parameters than TMPL due to the extra
1646 in-charge parameter in constructors and destructors. */
1647 in_charge = spec_types;
1648 spec_types = TREE_CHAIN (spec_types);
1650 if (DECL_HAS_VTT_PARM_P (decl))
1653 spec_types = TREE_CHAIN (spec_types);
1657 /* Compute the merged default arguments. */
1659 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1661 /* Compute the new FUNCTION_TYPE. */
1665 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1670 /* Put the in-charge parameter back. */
1671 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1672 TREE_VALUE (in_charge),
1675 new_type = build_method_type_directly (object_type,
1676 TREE_TYPE (old_type),
1680 new_type = build_function_type (TREE_TYPE (old_type),
1682 new_type = cp_build_type_attribute_variant (new_type,
1683 TYPE_ATTRIBUTES (old_type));
1684 new_type = build_exception_variant (new_type,
1685 TYPE_RAISES_EXCEPTIONS (old_type));
1686 TREE_TYPE (decl) = new_type;
1689 /* Check to see if the function just declared, as indicated in
1690 DECLARATOR, and in DECL, is a specialization of a function
1691 template. We may also discover that the declaration is an explicit
1692 instantiation at this point.
1694 Returns DECL, or an equivalent declaration that should be used
1695 instead if all goes well. Issues an error message if something is
1696 amiss. Returns error_mark_node if the error is not easily
1699 FLAGS is a bitmask consisting of the following flags:
1701 2: The function has a definition.
1702 4: The function is a friend.
1704 The TEMPLATE_COUNT is the number of references to qualifying
1705 template classes that appeared in the name of the function. For
1708 template <class T> struct S { void f(); };
1711 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1712 classes are not counted in the TEMPLATE_COUNT, so that in
1714 template <class T> struct S {};
1715 template <> struct S<int> { void f(); }
1716 template <> void S<int>::f();
1718 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1719 invalid; there should be no template <>.)
1721 If the function is a specialization, it is marked as such via
1722 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1723 is set up correctly, and it is added to the list of specializations
1724 for that template. */
1727 check_explicit_specialization (tree declarator,
1732 int have_def = flags & 2;
1733 int is_friend = flags & 4;
1734 int specialization = 0;
1735 int explicit_instantiation = 0;
1736 int member_specialization = 0;
1737 tree ctype = DECL_CLASS_CONTEXT (decl);
1738 tree dname = DECL_NAME (decl);
1741 tsk = current_tmpl_spec_kind (template_count);
1746 if (processing_specialization)
1749 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1751 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1754 /* This could be something like:
1756 template <class T> void f(T);
1757 class S { friend void f<>(int); } */
1761 /* This case handles bogus declarations like template <>
1762 template <class T> void f<int>(); */
1764 error ("template-id %qD in declaration of primary template",
1771 case tsk_invalid_member_spec:
1772 /* The error has already been reported in
1773 check_specialization_scope. */
1774 return error_mark_node;
1776 case tsk_invalid_expl_inst:
1777 error ("template parameter list used in explicit instantiation");
1783 error ("definition provided for explicit instantiation");
1785 explicit_instantiation = 1;
1788 case tsk_excessive_parms:
1789 case tsk_insufficient_parms:
1790 if (tsk == tsk_excessive_parms)
1791 error ("too many template parameter lists in declaration of %qD",
1793 else if (template_header_count)
1794 error("too few template parameter lists in declaration of %qD", decl);
1796 error("explicit specialization of %qD must be introduced by "
1797 "`template <>'", decl);
1801 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1803 member_specialization = 1;
1809 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1811 /* This case handles bogus declarations like template <>
1812 template <class T> void f<int>(); */
1814 if (uses_template_parms (declarator))
1815 error ("function template partial specialization %qD "
1816 "is not allowed", declarator);
1818 error ("template-id %qD in declaration of primary template",
1823 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1824 /* This is a specialization of a member template, without
1825 specialization the containing class. Something like:
1827 template <class T> struct S {
1828 template <class U> void f (U);
1830 template <> template <class U> void S<int>::f(U) {}
1832 That's a specialization -- but of the entire template. */
1840 if (specialization || member_specialization)
1842 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1843 for (; t; t = TREE_CHAIN (t))
1844 if (TREE_PURPOSE (t))
1847 ("default argument specified in explicit specialization");
1850 if (current_lang_name == lang_name_c)
1851 error ("template specialization with C linkage");
1854 if (specialization || member_specialization || explicit_instantiation)
1856 tree tmpl = NULL_TREE;
1857 tree targs = NULL_TREE;
1859 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1860 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1864 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1869 /* If there is no class context, the explicit instantiation
1870 must be at namespace scope. */
1871 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1873 /* Find the namespace binding, using the declaration
1875 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1878 declarator = lookup_template_function (fns, NULL_TREE);
1881 if (declarator == error_mark_node)
1882 return error_mark_node;
1884 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1886 if (!explicit_instantiation)
1887 /* A specialization in class scope. This is invalid,
1888 but the error will already have been flagged by
1889 check_specialization_scope. */
1890 return error_mark_node;
1893 /* It's not valid to write an explicit instantiation in
1896 class C { template void f(); }
1898 This case is caught by the parser. However, on
1901 template class C { void f(); };
1903 (which is invalid) we can get here. The error will be
1910 else if (ctype != NULL_TREE
1911 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1914 /* Find the list of functions in ctype that have the same
1915 name as the declared function. */
1916 tree name = TREE_OPERAND (declarator, 0);
1917 tree fns = NULL_TREE;
1920 if (constructor_name_p (name, ctype))
1922 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1924 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1925 : !TYPE_HAS_DESTRUCTOR (ctype))
1927 /* From [temp.expl.spec]:
1929 If such an explicit specialization for the member
1930 of a class template names an implicitly-declared
1931 special member function (clause _special_), the
1932 program is ill-formed.
1934 Similar language is found in [temp.explicit]. */
1935 error ("specialization of implicitly-declared special member function");
1936 return error_mark_node;
1939 name = is_constructor ? ctor_identifier : dtor_identifier;
1942 if (!DECL_CONV_FN_P (decl))
1944 idx = lookup_fnfields_1 (ctype, name);
1946 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1953 /* For a type-conversion operator, we cannot do a
1954 name-based lookup. We might be looking for `operator
1955 int' which will be a specialization of `operator T'.
1956 So, we find *all* the conversion operators, and then
1957 select from them. */
1960 methods = CLASSTYPE_METHOD_VEC (ctype);
1962 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1963 VEC_iterate (tree, methods, idx, ovl);
1966 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1967 /* There are no more conversion functions. */
1970 /* Glue all these conversion functions together
1971 with those we already have. */
1972 for (; ovl; ovl = OVL_NEXT (ovl))
1973 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1977 if (fns == NULL_TREE)
1979 error ("no member function %qD declared in %qT", name, ctype);
1980 return error_mark_node;
1983 TREE_OPERAND (declarator, 0) = fns;
1986 /* Figure out what exactly is being specialized at this point.
1987 Note that for an explicit instantiation, even one for a
1988 member function, we cannot tell apriori whether the
1989 instantiation is for a member template, or just a member
1990 function of a template class. Even if a member template is
1991 being instantiated, the member template arguments may be
1992 elided if they can be deduced from the rest of the
1994 tmpl = determine_specialization (declarator, decl,
1996 member_specialization,
1999 if (!tmpl || tmpl == error_mark_node)
2000 /* We couldn't figure out what this declaration was
2002 return error_mark_node;
2005 tree gen_tmpl = most_general_template (tmpl);
2007 if (explicit_instantiation)
2009 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2010 is done by do_decl_instantiation later. */
2012 int arg_depth = TMPL_ARGS_DEPTH (targs);
2013 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2015 if (arg_depth > parm_depth)
2017 /* If TMPL is not the most general template (for
2018 example, if TMPL is a friend template that is
2019 injected into namespace scope), then there will
2020 be too many levels of TARGS. Remove some of them
2025 new_targs = make_tree_vec (parm_depth);
2026 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2027 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2028 = TREE_VEC_ELT (targs, i);
2032 return instantiate_template (tmpl, targs, tf_error);
2035 /* If we thought that the DECL was a member function, but it
2036 turns out to be specializing a static member function,
2037 make DECL a static member function as well. */
2038 if (DECL_STATIC_FUNCTION_P (tmpl)
2039 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2040 revert_static_member_fn (decl);
2042 /* If this is a specialization of a member template of a
2043 template class. In we want to return the TEMPLATE_DECL,
2044 not the specialization of it. */
2045 if (tsk == tsk_template)
2047 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2048 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2051 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2052 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2053 = DECL_SOURCE_LOCATION (decl);
2058 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2059 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2061 /* Inherit default function arguments from the template
2062 DECL is specializing. */
2063 copy_default_args_to_explicit_spec (decl);
2065 /* This specialization has the same protection as the
2066 template it specializes. */
2067 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2068 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2070 if (is_friend && !have_def)
2071 /* This is not really a declaration of a specialization.
2072 It's just the name of an instantiation. But, it's not
2073 a request for an instantiation, either. */
2074 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2075 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2076 /* This is indeed a specialization. In case of constructors
2077 and destructors, we need in-charge and not-in-charge
2078 versions in V3 ABI. */
2079 clone_function_decl (decl, /*update_method_vec_p=*/0);
2081 /* Register this specialization so that we can find it
2083 decl = register_specialization (decl, gen_tmpl, targs);
2090 /* TYPE is being declared. Verify that the use of template headers
2091 and such is reasonable. Issue error messages if not. */
2094 maybe_check_template_type (tree type)
2096 if (template_header_count)
2098 /* We are in the scope of some `template <...>' header. */
2101 = template_class_depth_real (TYPE_CONTEXT (type),
2102 /*count_specializations=*/1);
2104 if (template_header_count <= context_depth)
2105 /* This is OK; the template headers are for the context. We
2106 are actually too lenient here; like
2107 check_explicit_specialization we should consider the number
2108 of template types included in the actual declaration. For
2111 template <class T> struct S {
2112 template <class U> template <class V>
2118 template <class T> struct S {
2119 template <class U> struct I;
2122 template <class T> template <class U.
2127 else if (template_header_count > context_depth + 1)
2128 /* There are two many template parameter lists. */
2129 error ("too many template parameter lists in declaration of %qT", type);
2133 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2134 parameters. These are represented in the same format used for
2135 DECL_TEMPLATE_PARMS. */
2138 comp_template_parms (tree parms1, tree parms2)
2143 if (parms1 == parms2)
2146 for (p1 = parms1, p2 = parms2;
2147 p1 != NULL_TREE && p2 != NULL_TREE;
2148 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2150 tree t1 = TREE_VALUE (p1);
2151 tree t2 = TREE_VALUE (p2);
2154 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2155 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2157 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2160 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2162 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2163 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2165 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2168 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2170 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2175 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2176 /* One set of parameters has more parameters lists than the
2183 /* Complain if DECL shadows a template parameter.
2185 [temp.local]: A template-parameter shall not be redeclared within its
2186 scope (including nested scopes). */
2189 check_template_shadow (tree decl)
2193 /* If we're not in a template, we can't possibly shadow a template
2195 if (!current_template_parms)
2198 /* Figure out what we're shadowing. */
2199 if (TREE_CODE (decl) == OVERLOAD)
2200 decl = OVL_CURRENT (decl);
2201 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2203 /* If there's no previous binding for this name, we're not shadowing
2204 anything, let alone a template parameter. */
2208 /* If we're not shadowing a template parameter, we're done. Note
2209 that OLDDECL might be an OVERLOAD (or perhaps even an
2210 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2212 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2215 /* We check for decl != olddecl to avoid bogus errors for using a
2216 name inside a class. We check TPFI to avoid duplicate errors for
2217 inline member templates. */
2219 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2222 cp_error_at ("declaration of %q#D", decl);
2223 cp_error_at (" shadows template parm %q#D", olddecl);
2226 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2227 ORIG_LEVEL, DECL, and TYPE. */
2230 build_template_parm_index (int index,
2236 tree t = make_node (TEMPLATE_PARM_INDEX);
2237 TEMPLATE_PARM_IDX (t) = index;
2238 TEMPLATE_PARM_LEVEL (t) = level;
2239 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2240 TEMPLATE_PARM_DECL (t) = decl;
2241 TREE_TYPE (t) = type;
2242 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2243 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2244 TREE_READONLY (t) = TREE_READONLY (decl);
2249 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2250 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2251 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2252 new one is created. */
2255 reduce_template_parm_level (tree index, tree type, int levels)
2257 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2258 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2259 != TEMPLATE_PARM_LEVEL (index) - levels))
2261 tree orig_decl = TEMPLATE_PARM_DECL (index);
2264 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2265 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2266 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2267 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2268 DECL_ARTIFICIAL (decl) = 1;
2269 SET_DECL_TEMPLATE_PARM_P (decl);
2271 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2272 TEMPLATE_PARM_LEVEL (index) - levels,
2273 TEMPLATE_PARM_ORIG_LEVEL (index),
2275 TEMPLATE_PARM_DESCENDANTS (index) = t;
2277 /* Template template parameters need this. */
2278 DECL_TEMPLATE_PARMS (decl)
2279 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2282 return TEMPLATE_PARM_DESCENDANTS (index);
2285 /* Process information from new template parameter NEXT and append it to the
2286 LIST being built. This new parameter is a non-type parameter iff
2287 IS_NON_TYPE is true. */
2290 process_template_parm (tree list, tree next, bool is_non_type)
2298 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2299 defval = TREE_PURPOSE (parm);
2303 tree p = TREE_VALUE (tree_last (list));
2305 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2306 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2308 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2316 parm = TREE_VALUE (parm);
2318 SET_DECL_TEMPLATE_PARM_P (parm);
2322 The top-level cv-qualifiers on the template-parameter are
2323 ignored when determining its type. */
2324 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2326 /* A template parameter is not modifiable. */
2327 TREE_CONSTANT (parm) = 1;
2328 TREE_INVARIANT (parm) = 1;
2329 TREE_READONLY (parm) = 1;
2330 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2331 TREE_TYPE (parm) = void_type_node;
2332 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2333 TREE_CONSTANT (decl) = 1;
2334 TREE_INVARIANT (decl) = 1;
2335 TREE_READONLY (decl) = 1;
2336 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2337 = build_template_parm_index (idx, processing_template_decl,
2338 processing_template_decl,
2339 decl, TREE_TYPE (parm));
2344 parm = TREE_VALUE (TREE_VALUE (parm));
2346 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2348 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2349 /* This is for distinguishing between real templates and template
2350 template parameters */
2351 TREE_TYPE (parm) = t;
2352 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2357 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2358 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2359 decl = build_decl (TYPE_DECL, parm, t);
2362 TYPE_NAME (t) = decl;
2363 TYPE_STUB_DECL (t) = decl;
2365 TEMPLATE_TYPE_PARM_INDEX (t)
2366 = build_template_parm_index (idx, processing_template_decl,
2367 processing_template_decl,
2368 decl, TREE_TYPE (parm));
2370 DECL_ARTIFICIAL (decl) = 1;
2371 SET_DECL_TEMPLATE_PARM_P (decl);
2373 parm = build_tree_list (defval, parm);
2374 return chainon (list, parm);
2377 /* The end of a template parameter list has been reached. Process the
2378 tree list into a parameter vector, converting each parameter into a more
2379 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2383 end_template_parm_list (tree parms)
2387 tree saved_parmlist = make_tree_vec (list_length (parms));
2389 current_template_parms
2390 = tree_cons (size_int (processing_template_decl),
2391 saved_parmlist, current_template_parms);
2393 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2395 next = TREE_CHAIN (parm);
2396 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2397 TREE_CHAIN (parm) = NULL_TREE;
2400 --processing_template_parmlist;
2402 return saved_parmlist;
2405 /* end_template_decl is called after a template declaration is seen. */
2408 end_template_decl (void)
2410 reset_specialization ();
2412 if (! processing_template_decl)
2415 /* This matches the pushlevel in begin_template_parm_list. */
2418 --processing_template_decl;
2419 current_template_parms = TREE_CHAIN (current_template_parms);
2422 /* Given a template argument vector containing the template PARMS.
2423 The innermost PARMS are given first. */
2426 current_template_args (void)
2429 tree args = NULL_TREE;
2430 int length = TMPL_PARMS_DEPTH (current_template_parms);
2433 /* If there is only one level of template parameters, we do not
2434 create a TREE_VEC of TREE_VECs. Instead, we return a single
2435 TREE_VEC containing the arguments. */
2437 args = make_tree_vec (length);
2439 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2441 tree a = copy_node (TREE_VALUE (header));
2444 TREE_TYPE (a) = NULL_TREE;
2445 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2447 tree t = TREE_VEC_ELT (a, i);
2449 /* T will be a list if we are called from within a
2450 begin/end_template_parm_list pair, but a vector directly
2451 if within a begin/end_member_template_processing pair. */
2452 if (TREE_CODE (t) == TREE_LIST)
2456 if (TREE_CODE (t) == TYPE_DECL
2457 || TREE_CODE (t) == TEMPLATE_DECL)
2460 t = DECL_INITIAL (t);
2461 TREE_VEC_ELT (a, i) = t;
2466 TREE_VEC_ELT (args, --l) = a;
2474 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2475 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2476 a member template. Used by push_template_decl below. */
2479 build_template_decl (tree decl, tree parms, bool member_template_p)
2481 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2482 DECL_TEMPLATE_PARMS (tmpl) = parms;
2483 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2484 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2485 if (DECL_LANG_SPECIFIC (decl))
2487 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2488 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2489 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2490 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2491 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2492 if (DECL_OVERLOADED_OPERATOR_P (decl))
2493 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2494 DECL_OVERLOADED_OPERATOR_P (decl));
2500 struct template_parm_data
2502 /* The level of the template parameters we are currently
2506 /* The index of the specialization argument we are currently
2510 /* An array whose size is the number of template parameters. The
2511 elements are nonzero if the parameter has been used in any one
2512 of the arguments processed so far. */
2515 /* An array whose size is the number of template arguments. The
2516 elements are nonzero if the argument makes use of template
2517 parameters of this level. */
2518 int* arg_uses_template_parms;
2521 /* Subroutine of push_template_decl used to see if each template
2522 parameter in a partial specialization is used in the explicit
2523 argument list. If T is of the LEVEL given in DATA (which is
2524 treated as a template_parm_data*), then DATA->PARMS is marked
2528 mark_template_parm (tree t, void* data)
2532 struct template_parm_data* tpd = (struct template_parm_data*) data;
2534 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2536 level = TEMPLATE_PARM_LEVEL (t);
2537 idx = TEMPLATE_PARM_IDX (t);
2541 level = TEMPLATE_TYPE_LEVEL (t);
2542 idx = TEMPLATE_TYPE_IDX (t);
2545 if (level == tpd->level)
2547 tpd->parms[idx] = 1;
2548 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2551 /* Return zero so that for_each_template_parm will continue the
2552 traversal of the tree; we want to mark *every* template parm. */
2556 /* Process the partial specialization DECL. */
2559 process_partial_specialization (tree decl)
2561 tree type = TREE_TYPE (decl);
2562 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2563 tree specargs = CLASSTYPE_TI_ARGS (type);
2564 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2565 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2566 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2567 int nargs = TREE_VEC_LENGTH (inner_args);
2568 int ntparms = TREE_VEC_LENGTH (inner_parms);
2570 int did_error_intro = 0;
2571 struct template_parm_data tpd;
2572 struct template_parm_data tpd2;
2574 /* We check that each of the template parameters given in the
2575 partial specialization is used in the argument list to the
2576 specialization. For example:
2578 template <class T> struct S;
2579 template <class T> struct S<T*>;
2581 The second declaration is OK because `T*' uses the template
2582 parameter T, whereas
2584 template <class T> struct S<int>;
2586 is no good. Even trickier is:
2597 The S2<T> declaration is actually invalid; it is a
2598 full-specialization. Of course,
2601 struct S2<T (*)(U)>;
2603 or some such would have been OK. */
2604 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2605 tpd.parms = alloca (sizeof (int) * ntparms);
2606 memset (tpd.parms, 0, sizeof (int) * ntparms);
2608 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2609 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2610 for (i = 0; i < nargs; ++i)
2612 tpd.current_arg = i;
2613 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2614 &mark_template_parm,
2618 for (i = 0; i < ntparms; ++i)
2619 if (tpd.parms[i] == 0)
2621 /* One of the template parms was not used in the
2623 if (!did_error_intro)
2625 error ("template parameters not used in partial specialization:");
2626 did_error_intro = 1;
2629 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2632 /* [temp.class.spec]
2634 The argument list of the specialization shall not be identical to
2635 the implicit argument list of the primary template. */
2636 if (comp_template_args
2638 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2640 error ("partial specialization %qT does not specialize any template arguments", type);
2642 /* [temp.class.spec]
2644 A partially specialized non-type argument expression shall not
2645 involve template parameters of the partial specialization except
2646 when the argument expression is a simple identifier.
2648 The type of a template parameter corresponding to a specialized
2649 non-type argument shall not be dependent on a parameter of the
2651 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2653 for (i = 0; i < nargs; ++i)
2655 tree arg = TREE_VEC_ELT (inner_args, i);
2656 if (/* These first two lines are the `non-type' bit. */
2658 && TREE_CODE (arg) != TEMPLATE_DECL
2659 /* This next line is the `argument expression is not just a
2660 simple identifier' condition and also the `specialized
2661 non-type argument' bit. */
2662 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2664 if (tpd.arg_uses_template_parms[i])
2665 error ("template argument %qE involves template parameter(s)", arg);
2668 /* Look at the corresponding template parameter,
2669 marking which template parameters its type depends
2672 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2677 /* We haven't yet initialized TPD2. Do so now. */
2678 tpd2.arg_uses_template_parms
2679 = alloca (sizeof (int) * nargs);
2680 /* The number of parameters here is the number in the
2681 main template, which, as checked in the assertion
2683 tpd2.parms = alloca (sizeof (int) * nargs);
2685 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2688 /* Mark the template parameters. But this time, we're
2689 looking for the template parameters of the main
2690 template, not in the specialization. */
2691 tpd2.current_arg = i;
2692 tpd2.arg_uses_template_parms[i] = 0;
2693 memset (tpd2.parms, 0, sizeof (int) * nargs);
2694 for_each_template_parm (type,
2695 &mark_template_parm,
2699 if (tpd2.arg_uses_template_parms [i])
2701 /* The type depended on some template parameters.
2702 If they are fully specialized in the
2703 specialization, that's OK. */
2705 for (j = 0; j < nargs; ++j)
2706 if (tpd2.parms[j] != 0
2707 && tpd.arg_uses_template_parms [j])
2709 error ("type %qT of template argument %qE depends "
2710 "on template parameter(s)",
2720 if (retrieve_specialization (maintmpl, specargs,
2721 /*class_specializations_p=*/true))
2722 /* We've already got this specialization. */
2725 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2726 = tree_cons (inner_args, inner_parms,
2727 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2728 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2732 /* Check that a template declaration's use of default arguments is not
2733 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2734 nonzero if DECL is the thing declared by a primary template.
2735 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2738 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2741 int last_level_to_check;
2746 A default template-argument shall not be specified in a
2747 function template declaration or a function template definition, nor
2748 in the template-parameter-list of the definition of a member of a
2751 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2752 /* You can't have a function template declaration in a local
2753 scope, nor you can you define a member of a class template in a
2757 if (current_class_type
2758 && !TYPE_BEING_DEFINED (current_class_type)
2759 && DECL_LANG_SPECIFIC (decl)
2760 /* If this is either a friend defined in the scope of the class
2761 or a member function. */
2762 && (DECL_FUNCTION_MEMBER_P (decl)
2763 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2764 : DECL_FRIEND_CONTEXT (decl)
2765 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2767 /* And, if it was a member function, it really was defined in
2768 the scope of the class. */
2769 && (!DECL_FUNCTION_MEMBER_P (decl)
2770 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2771 /* We already checked these parameters when the template was
2772 declared, so there's no need to do it again now. This function
2773 was defined in class scope, but we're processing it's body now
2774 that the class is complete. */
2779 If a template-parameter has a default template-argument, all
2780 subsequent template-parameters shall have a default
2781 template-argument supplied. */
2782 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2784 tree inner_parms = TREE_VALUE (parm_level);
2785 int ntparms = TREE_VEC_LENGTH (inner_parms);
2786 int seen_def_arg_p = 0;
2789 for (i = 0; i < ntparms; ++i)
2791 tree parm = TREE_VEC_ELT (inner_parms, i);
2792 if (TREE_PURPOSE (parm))
2794 else if (seen_def_arg_p)
2796 error ("no default argument for %qD", TREE_VALUE (parm));
2797 /* For better subsequent error-recovery, we indicate that
2798 there should have been a default argument. */
2799 TREE_PURPOSE (parm) = error_mark_node;
2804 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2805 /* For an ordinary class template, default template arguments are
2806 allowed at the innermost level, e.g.:
2807 template <class T = int>
2809 but, in a partial specialization, they're not allowed even
2810 there, as we have in [temp.class.spec]:
2812 The template parameter list of a specialization shall not
2813 contain default template argument values.
2815 So, for a partial specialization, or for a function template,
2816 we look at all of them. */
2819 /* But, for a primary class template that is not a partial
2820 specialization we look at all template parameters except the
2822 parms = TREE_CHAIN (parms);
2824 /* Figure out what error message to issue. */
2825 if (TREE_CODE (decl) == FUNCTION_DECL)
2826 msg = "default template arguments may not be used in function templates";
2827 else if (is_partial)
2828 msg = "default template arguments may not be used in partial specializations";
2830 msg = "default argument for template parameter for class enclosing %qD";
2832 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2833 /* If we're inside a class definition, there's no need to
2834 examine the parameters to the class itself. On the one
2835 hand, they will be checked when the class is defined, and,
2836 on the other, default arguments are valid in things like:
2837 template <class T = double>
2838 struct S { template <class U> void f(U); };
2839 Here the default argument for `S' has no bearing on the
2840 declaration of `f'. */
2841 last_level_to_check = template_class_depth (current_class_type) + 1;
2843 /* Check everything. */
2844 last_level_to_check = 0;
2846 for (parm_level = parms;
2847 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2848 parm_level = TREE_CHAIN (parm_level))
2850 tree inner_parms = TREE_VALUE (parm_level);
2854 ntparms = TREE_VEC_LENGTH (inner_parms);
2855 for (i = 0; i < ntparms; ++i)
2856 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2864 /* Clear out the default argument so that we are not
2866 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2869 /* At this point, if we're still interested in issuing messages,
2870 they must apply to classes surrounding the object declared. */
2872 msg = "default argument for template parameter for class enclosing %qD";
2876 /* Worker for push_template_decl_real, called via
2877 for_each_template_parm. DATA is really an int, indicating the
2878 level of the parameters we are interested in. If T is a template
2879 parameter of that level, return nonzero. */
2882 template_parm_this_level_p (tree t, void* data)
2884 int this_level = *(int *)data;
2887 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2888 level = TEMPLATE_PARM_LEVEL (t);
2890 level = TEMPLATE_TYPE_LEVEL (t);
2891 return level == this_level;
2894 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2895 parameters given by current_template_args, or reuses a
2896 previously existing one, if appropriate. Returns the DECL, or an
2897 equivalent one, if it is replaced via a call to duplicate_decls.
2899 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2902 push_template_decl_real (tree decl, int is_friend)
2910 int new_template_p = 0;
2911 /* True if the template is a member template, in the sense of
2913 bool member_template_p = false;
2915 if (decl == error_mark_node)
2918 /* See if this is a partial specialization. */
2919 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2920 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2921 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2923 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2926 /* For a friend, we want the context of the friend function, not
2927 the type of which it is a friend. */
2928 ctx = DECL_CONTEXT (decl);
2929 else if (CP_DECL_CONTEXT (decl)
2930 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2931 /* In the case of a virtual function, we want the class in which
2933 ctx = CP_DECL_CONTEXT (decl);
2935 /* Otherwise, if we're currently defining some class, the DECL
2936 is assumed to be a member of the class. */
2937 ctx = current_scope ();
2939 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2942 if (!DECL_CONTEXT (decl))
2943 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2945 /* See if this is a primary template. */
2946 primary = template_parm_scope_p ();
2950 if (DECL_CLASS_SCOPE_P (decl))
2951 member_template_p = true;
2952 if (current_lang_name == lang_name_c)
2953 error ("template with C linkage");
2954 else if (TREE_CODE (decl) == TYPE_DECL
2955 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2956 error ("template class without a name");
2957 else if (TREE_CODE (decl) == FUNCTION_DECL)
2959 if (DECL_DESTRUCTOR_P (decl))
2963 A destructor shall not be a member template. */
2964 error ("destructor %qD declared as member template", decl);
2965 return error_mark_node;
2967 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2968 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2969 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2970 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2971 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2972 == void_list_node)))
2974 /* [basic.stc.dynamic.allocation]
2976 An allocation function can be a function
2977 template. ... Template allocation functions shall
2978 have two or more parameters. */
2979 error ("invalid template declaration of %qD", decl);
2983 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2984 && CLASS_TYPE_P (TREE_TYPE (decl)))
2985 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx)))
2989 error ("template declaration of %q#D", decl);
2990 return error_mark_node;
2994 /* Check to see that the rules regarding the use of default
2995 arguments are not being violated. */
2996 check_default_tmpl_args (decl, current_template_parms,
2997 primary, is_partial);
3000 return process_partial_specialization (decl);
3002 args = current_template_args ();
3005 || TREE_CODE (ctx) == FUNCTION_DECL
3006 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3007 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3009 if (DECL_LANG_SPECIFIC (decl)
3010 && DECL_TEMPLATE_INFO (decl)
3011 && DECL_TI_TEMPLATE (decl))
3012 tmpl = DECL_TI_TEMPLATE (decl);
3013 /* If DECL is a TYPE_DECL for a class-template, then there won't
3014 be DECL_LANG_SPECIFIC. The information equivalent to
3015 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3016 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3017 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3018 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3020 /* Since a template declaration already existed for this
3021 class-type, we must be redeclaring it here. Make sure
3022 that the redeclaration is valid. */
3023 redeclare_class_template (TREE_TYPE (decl),
3024 current_template_parms);
3025 /* We don't need to create a new TEMPLATE_DECL; just use the
3026 one we already had. */
3027 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3031 tmpl = build_template_decl (decl, current_template_parms,
3035 if (DECL_LANG_SPECIFIC (decl)
3036 && DECL_TEMPLATE_SPECIALIZATION (decl))
3038 /* A specialization of a member template of a template
3040 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3041 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3042 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3048 tree a, t, current, parms;
3051 if (TREE_CODE (decl) == TYPE_DECL)
3053 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3054 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3055 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3056 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3057 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3060 error ("%qD does not declare a template type", decl);
3064 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3066 error ("template definition of non-template %q#D", decl);
3070 tmpl = DECL_TI_TEMPLATE (decl);
3072 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3073 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3074 && DECL_TEMPLATE_SPECIALIZATION (decl)
3075 && DECL_MEMBER_TEMPLATE_P (tmpl))
3079 /* The declaration is a specialization of a member
3080 template, declared outside the class. Therefore, the
3081 innermost template arguments will be NULL, so we
3082 replace them with the arguments determined by the
3083 earlier call to check_explicit_specialization. */
3084 args = DECL_TI_ARGS (decl);
3087 = build_template_decl (decl, current_template_parms,
3089 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3090 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3091 DECL_TI_TEMPLATE (decl) = new_tmpl;
3092 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3093 DECL_TEMPLATE_INFO (new_tmpl)
3094 = tree_cons (tmpl, args, NULL_TREE);
3096 register_specialization (new_tmpl,
3097 most_general_template (tmpl),
3102 /* Make sure the template headers we got make sense. */
3104 parms = DECL_TEMPLATE_PARMS (tmpl);
3105 i = TMPL_PARMS_DEPTH (parms);
3106 if (TMPL_ARGS_DEPTH (args) != i)
3108 error ("expected %d levels of template parms for %q#D, got %d",
3109 i, decl, TMPL_ARGS_DEPTH (args));
3112 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3114 a = TMPL_ARGS_LEVEL (args, i);
3115 t = INNERMOST_TEMPLATE_PARMS (parms);
3117 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3119 if (current == decl)
3120 error ("got %d template parameters for %q#D",
3121 TREE_VEC_LENGTH (a), decl);
3123 error ("got %d template parameters for %q#T",
3124 TREE_VEC_LENGTH (a), current);
3125 error (" but %d required", TREE_VEC_LENGTH (t));
3128 /* Perhaps we should also check that the parms are used in the
3129 appropriate qualifying scopes in the declarator? */
3131 if (current == decl)
3134 current = TYPE_CONTEXT (current);
3138 DECL_TEMPLATE_RESULT (tmpl) = decl;
3139 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3141 /* Push template declarations for global functions and types. Note
3142 that we do not try to push a global template friend declared in a
3143 template class; such a thing may well depend on the template
3144 parameters of the class. */
3145 if (new_template_p && !ctx
3146 && !(is_friend && template_class_depth (current_class_type) > 0))
3147 tmpl = pushdecl_namespace_level (tmpl);
3151 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3152 if (DECL_CONV_FN_P (tmpl))
3154 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3156 /* It is a conversion operator. See if the type converted to
3157 depends on innermost template operands. */
3159 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3161 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3165 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3166 back to its most general template. If TMPL is a specialization,
3167 ARGS may only have the innermost set of arguments. Add the missing
3168 argument levels if necessary. */
3169 if (DECL_TEMPLATE_INFO (tmpl))
3170 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3172 info = tree_cons (tmpl, args, NULL_TREE);
3174 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3176 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3177 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3178 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3179 /* Don't change the name if we've already set it up. */
3180 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3181 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3183 else if (DECL_LANG_SPECIFIC (decl))
3184 DECL_TEMPLATE_INFO (decl) = info;
3186 return DECL_TEMPLATE_RESULT (tmpl);
3190 push_template_decl (tree decl)
3192 return push_template_decl_real (decl, 0);
3195 /* Called when a class template TYPE is redeclared with the indicated
3196 template PARMS, e.g.:
3198 template <class T> struct S;
3199 template <class T> struct S {}; */
3202 redeclare_class_template (tree type, tree parms)
3208 if (!TYPE_TEMPLATE_INFO (type))
3210 error ("%qT is not a template type", type);
3214 tmpl = TYPE_TI_TEMPLATE (type);
3215 if (!PRIMARY_TEMPLATE_P (tmpl))
3216 /* The type is nested in some template class. Nothing to worry
3217 about here; there are no new template parameters for the nested
3221 parms = INNERMOST_TEMPLATE_PARMS (parms);
3222 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3224 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3226 cp_error_at ("previous declaration %qD", tmpl);
3227 error ("used %d template parameter%s instead of %d",
3228 TREE_VEC_LENGTH (tmpl_parms),
3229 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
3230 TREE_VEC_LENGTH (parms));
3234 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3236 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3237 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3238 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3239 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3241 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3243 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3244 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3245 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3247 cp_error_at ("template parameter %q#D", tmpl_parm);
3248 error ("redeclared here as %q#D", parm);
3252 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3254 /* We have in [temp.param]:
3256 A template-parameter may not be given default arguments
3257 by two different declarations in the same scope. */
3258 error ("redefinition of default argument for %q#D", parm);
3259 error ("%J original definition appeared here", tmpl_parm);
3263 if (parm_default != NULL_TREE)
3264 /* Update the previous template parameters (which are the ones
3265 that will really count) with the new default value. */
3266 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3267 else if (tmpl_default != NULL_TREE)
3268 /* Update the new parameters, too; they'll be used as the
3269 parameters for any members. */
3270 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3274 /* Simplify EXPR if it is a non-dependent expression. Returns the
3275 (possibly simplified) expression. */
3278 fold_non_dependent_expr (tree expr)
3280 /* If we're in a template, but EXPR isn't value dependent, simplify
3281 it. We're supposed to treat:
3283 template <typename T> void f(T[1 + 1]);
3284 template <typename T> void f(T[2]);
3286 as two declarations of the same function, for example. */
3287 if (processing_template_decl
3288 && !type_dependent_expression_p (expr)
3289 && !value_dependent_expression_p (expr))
3291 HOST_WIDE_INT saved_processing_template_decl;
3293 saved_processing_template_decl = processing_template_decl;
3294 processing_template_decl = 0;
3295 expr = tsubst_copy_and_build (expr,
3298 /*in_decl=*/NULL_TREE,
3299 /*function_p=*/false);
3300 processing_template_decl = saved_processing_template_decl;
3305 /* Attempt to convert the non-type template parameter EXPR to the
3306 indicated TYPE. If the conversion is successful, return the
3307 converted value. If the conversion is unsuccessful, return
3308 NULL_TREE if we issued an error message, or error_mark_node if we
3309 did not. We issue error messages for out-and-out bad template
3310 parameters, but not simply because the conversion failed, since we
3311 might be just trying to do argument deduction. Both TYPE and EXPR
3312 must be non-dependent. */
3315 convert_nontype_argument (tree type, tree expr)
3319 /* If we are in a template, EXPR may be non-dependent, but still
3320 have a syntactic, rather than semantic, form. For example, EXPR
3321 might be a SCOPE_REF, rather than the VAR_DECL to which the
3322 SCOPE_REF refers. Preserving the qualifying scope is necessary
3323 so that access checking can be performed when the template is
3324 instantiated -- but here we need the resolved form so that we can
3325 convert the argument. */
3326 expr = fold_non_dependent_expr (expr);
3327 expr_type = TREE_TYPE (expr);
3329 /* A template-argument for a non-type, non-template
3330 template-parameter shall be one of:
3332 --an integral constant-expression of integral or enumeration
3335 --the name of a non-type template-parameter; or
3337 --the name of an object or function with external linkage,
3338 including function templates and function template-ids but
3339 excluding non-static class members, expressed as id-expression;
3342 --the address of an object or function with external linkage,
3343 including function templates and function template-ids but
3344 excluding non-static class members, expressed as & id-expression
3345 where the & is optional if the name refers to a function or
3348 --a pointer to member expressed as described in _expr.unary.op_. */
3350 /* An integral constant-expression can include const variables or
3351 . enumerators. Simplify things by folding them to their values,
3352 unless we're about to bind the declaration to a reference
3354 if (INTEGRAL_TYPE_P (expr_type) && TREE_CODE (type) != REFERENCE_TYPE)
3357 tree const_expr = decl_constant_value (expr);
3358 /* In a template, the initializer for a VAR_DECL may not be
3359 marked as TREE_CONSTANT, in which case decl_constant_value
3360 will not return the initializer. Handle that special case
3362 if (expr == const_expr
3363 && DECL_INTEGRAL_CONSTANT_VAR_P (expr)
3364 /* DECL_INITIAL can be NULL if we are processing a
3365 variable initialized to an expression involving itself.
3366 We know it is initialized to a constant -- but not what
3368 && DECL_INITIAL (expr))
3369 const_expr = DECL_INITIAL (expr);
3370 if (expr == const_expr)
3372 expr = fold_non_dependent_expr (const_expr);
3375 if (is_overloaded_fn (expr))
3376 /* OK for now. We'll check that it has external linkage later.
3377 Check this first since if expr_type is the unknown_type_node
3378 we would otherwise complain below. */
3380 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3382 if (TREE_CODE (expr) != PTRMEM_CST)
3385 else if (TYPE_PTR_P (expr_type)
3386 || TREE_CODE (expr_type) == ARRAY_TYPE
3387 || TREE_CODE (type) == REFERENCE_TYPE
3388 /* If expr is the address of an overloaded function, we
3389 will get the unknown_type_node at this point. */
3390 || expr_type == unknown_type_node)
3396 if (TREE_CODE (expr_type) == ARRAY_TYPE
3397 || (TREE_CODE (type) == REFERENCE_TYPE
3398 && TREE_CODE (e) != ADDR_EXPR))
3402 if (TREE_CODE (e) != ADDR_EXPR)
3405 error ("%qE is not a valid template argument", expr);
3406 if (TYPE_PTR_P (expr_type))
3408 if (TREE_CODE (TREE_TYPE (expr_type)) == FUNCTION_TYPE)
3409 error ("it must be the address of a function with external linkage");
3411 error ("it must be the address of an object with external linkage");
3413 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3414 error ("it must be a pointer-to-member of the form %<&X::Y%>");
3419 referent = TREE_OPERAND (e, 0);
3420 STRIP_NOPS (referent);
3423 if (TREE_CODE (referent) == STRING_CST)
3425 error ("string literal %qE is not a valid template argument "
3426 "because it is the address of an object with static linkage",
3431 if (TREE_CODE (referent) == SCOPE_REF)
3432 referent = TREE_OPERAND (referent, 1);
3434 if (is_overloaded_fn (referent))
3435 /* We'll check that it has external linkage later. */
3437 else if (TREE_CODE (referent) != VAR_DECL)
3439 else if (!DECL_EXTERNAL_LINKAGE_P (referent))
3441 error ("address of non-extern %qE cannot be used as "
3442 "template argument", referent);
3443 return error_mark_node;
3446 else if (INTEGRAL_TYPE_P (expr_type) || TYPE_PTR_TO_MEMBER_P (expr_type))
3448 if (! TREE_CONSTANT (expr))
3451 error ("non-constant %qE cannot be used as template argument", expr);
3458 error ("type %qT cannot be used as a value for a non-type "
3459 "template-parameter", expr);
3460 else if (DECL_P (expr))
3461 error ("invalid use of %qD as a non-type template-argument", expr);
3463 error ("invalid use of %qE as a non-type template-argument", expr);
3468 switch (TREE_CODE (type))
3470 HOST_WIDE_INT saved_processing_template_decl;
3475 /* For a non-type template-parameter of integral or enumeration
3476 type, integral promotions (_conv.prom_) and integral
3477 conversions (_conv.integral_) are applied. */
3478 if (!INTEGRAL_TYPE_P (expr_type))
3479 return error_mark_node;
3481 /* [conv.integral] does not allow conversions between two different
3482 enumeration types. */
3483 if (TREE_CODE (type) == ENUMERAL_TYPE
3484 && TREE_CODE (expr_type) == ENUMERAL_TYPE
3485 && !same_type_ignoring_top_level_qualifiers_p (type, expr_type))
3486 return error_mark_node;
3488 /* It's safe to call digest_init in this case; we know we're
3489 just converting one integral constant expression to another.
3491 saved_processing_template_decl = processing_template_decl;
3492 processing_template_decl = 0;
3493 expr = digest_init (type, expr, (tree*) 0);
3494 processing_template_decl = saved_processing_template_decl;
3496 if (TREE_CODE (expr) != INTEGER_CST)
3497 /* Curiously, some TREE_CONSTANT integral expressions do not
3498 simplify to integer constants. For example, `3 % 0',
3499 remains a TRUNC_MOD_EXPR. */
3508 /* For a non-type template-parameter of type pointer to data
3509 member, qualification conversions (_conv.qual_) are
3511 e = perform_qualification_conversions (type, expr);
3512 if (TREE_CODE (e) == NOP_EXPR)
3513 /* The call to perform_qualification_conversions will
3514 insert a NOP_EXPR over EXPR to do express conversion,
3515 if necessary. But, that will confuse us if we use
3516 this (converted) template parameter to instantiate
3517 another template; then the thing will not look like a
3518 valid template argument. So, just make a new
3519 constant, of the appropriate type. */
3520 e = make_ptrmem_cst (type, PTRMEM_CST_MEMBER (expr));
3526 tree type_pointed_to = TREE_TYPE (type);
3528 if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE)
3530 /* For a non-type template-parameter of type pointer to
3531 function, only the function-to-pointer conversion
3532 (_conv.func_) is applied. If the template-argument
3533 represents a set of overloaded functions (or a pointer to
3534 such), the matching function is selected from the set
3539 if (TREE_CODE (expr) == ADDR_EXPR)
3540 fns = TREE_OPERAND (expr, 0);
3544 fn = instantiate_type (type_pointed_to, fns, tf_none);
3546 if (fn == error_mark_node)
3547 return error_mark_node;
3549 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3551 if (really_overloaded_fn (fns))
3552 return error_mark_node;
3557 expr = build_unary_op (ADDR_EXPR, fn, 0);
3559 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3564 /* For a non-type template-parameter of type pointer to
3565 object, qualification conversions (_conv.qual_) and the
3566 array-to-pointer conversion (_conv.array_) are applied.
3567 [Note: In particular, neither the null pointer conversion
3568 (_conv.ptr_) nor the derived-to-base conversion
3569 (_conv.ptr_) are applied. Although 0 is a valid
3570 template-argument for a non-type template-parameter of
3571 integral type, it is not a valid template-argument for a
3572 non-type template-parameter of pointer type.]
3574 The call to decay_conversion performs the
3575 array-to-pointer conversion, if appropriate. */
3576 expr = decay_conversion (expr);
3578 if (expr == error_mark_node)
3579 return error_mark_node;
3581 return perform_qualification_conversions (type, expr);
3586 case REFERENCE_TYPE:
3588 tree type_referred_to = TREE_TYPE (type);
3590 /* If this expression already has reference type, get the
3591 underlying object. */
3592 if (TREE_CODE (expr_type) == REFERENCE_TYPE)
3594 if (TREE_CODE (expr) == NOP_EXPR
3595 && TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR)
3597 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3598 expr = TREE_OPERAND (expr, 0);
3599 expr_type = TREE_TYPE (expr);
3602 if (TREE_CODE (type_referred_to) == FUNCTION_TYPE)
3604 /* For a non-type template-parameter of type reference to
3605 function, no conversions apply. If the
3606 template-argument represents a set of overloaded
3607 functions, the matching function is selected from the
3608 set (_over.over_). */
3611 fn = instantiate_type (type_referred_to, expr, tf_none);
3613 if (fn == error_mark_node)
3614 return error_mark_node;
3616 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3618 if (really_overloaded_fn (expr))
3619 /* Don't issue an error here; we might get a different
3620 function if the overloading had worked out
3622 return error_mark_node;
3627 gcc_assert (same_type_p (type_referred_to, TREE_TYPE (fn)));
3632 /* For a non-type template-parameter of type reference to
3633 object, no conversions apply. The type referred to by the
3634 reference may be more cv-qualified than the (otherwise
3635 identical) type of the template-argument. The
3636 template-parameter is bound directly to the
3637 template-argument, which must be an lvalue. */
3638 if (!same_type_p (TYPE_MAIN_VARIANT (expr_type),
3639 TYPE_MAIN_VARIANT (type_referred_to))
3640 || !at_least_as_qualified_p (type_referred_to,
3642 || !real_lvalue_p (expr))
3643 return error_mark_node;
3646 cxx_mark_addressable (expr);
3647 return build_nop (type, build_address (expr));
3653 gcc_assert (TYPE_PTRMEMFUNC_P (type));
3655 /* For a non-type template-parameter of type pointer to member
3656 function, no conversions apply. If the template-argument
3657 represents a set of overloaded member functions, the
3658 matching member function is selected from the set
3661 if (!TYPE_PTRMEMFUNC_P (expr_type) &&
3662 expr_type != unknown_type_node)
3663 return error_mark_node;
3665 if (TREE_CODE (expr) == PTRMEM_CST)
3667 /* A ptr-to-member constant. */
3668 if (!same_type_p (type, expr_type))
3669 return error_mark_node;
3674 if (TREE_CODE (expr) != ADDR_EXPR)
3675 return error_mark_node;
3677 expr = instantiate_type (type, expr, tf_none);
3679 if (expr == error_mark_node)
3680 return error_mark_node;
3682 if (!same_type_p (type, TREE_TYPE (expr)))
3683 return error_mark_node;
3690 /* All non-type parameters must have one of these types. */
3694 return error_mark_node;
3697 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3698 template template parameters. Both PARM_PARMS and ARG_PARMS are
3699 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3702 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3703 the case, then extra parameters must have default arguments.
3705 Consider the example:
3706 template <class T, class Allocator = allocator> class vector;
3707 template<template <class U> class TT> class C;
3709 C<vector> is a valid instantiation. PARM_PARMS for the above code
3710 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3711 T and Allocator) and OUTER_ARGS contains the argument that is used to
3712 substitute the TT parameter. */
3715 coerce_template_template_parms (tree parm_parms,
3717 tsubst_flags_t complain,
3721 int nparms, nargs, i;
3724 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3725 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3727 nparms = TREE_VEC_LENGTH (parm_parms);
3728 nargs = TREE_VEC_LENGTH (arg_parms);
3730 /* The rule here is opposite of coerce_template_parms. */
3733 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3736 for (i = 0; i < nparms; ++i)
3738 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3739 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3741 if (arg == NULL_TREE || arg == error_mark_node
3742 || parm == NULL_TREE || parm == error_mark_node)
3745 if (TREE_CODE (arg) != TREE_CODE (parm))
3748 switch (TREE_CODE (parm))
3754 /* We encounter instantiations of templates like
3755 template <template <template <class> class> class TT>
3758 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3759 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3761 if (!coerce_template_template_parms
3762 (parmparm, argparm, complain, in_decl, outer_args))
3768 /* The tsubst call is used to handle cases such as
3770 template <int> class C {};
3771 template <class T, template <T> class TT> class D {};
3774 i.e. the parameter list of TT depends on earlier parameters. */
3775 if (!dependent_type_p (TREE_TYPE (arg))
3777 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3789 /* Convert the indicated template ARG as necessary to match the
3790 indicated template PARM. Returns the converted ARG, or
3791 error_mark_node if the conversion was unsuccessful. Error and
3792 warning messages are issued under control of COMPLAIN. This
3793 conversion is for the Ith parameter in the parameter list. ARGS is
3794 the full set of template arguments deduced so far. */
3797 convert_template_argument (tree parm,
3800 tsubst_flags_t complain,
3806 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3808 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3810 if (TREE_CODE (arg) == TREE_LIST
3811 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3813 /* The template argument was the name of some
3814 member function. That's usually
3815 invalid, but static members are OK. In any
3816 case, grab the underlying fields/functions
3817 and issue an error later if required. */
3818 arg = TREE_VALUE (arg);
3819 TREE_TYPE (arg) = unknown_type_node;
3822 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3823 requires_type = (TREE_CODE (parm) == TYPE_DECL
3824 || requires_tmpl_type);
3826 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3827 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3828 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3829 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3832 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3833 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3834 arg = TYPE_STUB_DECL (arg);
3836 is_type = TYPE_P (arg) || is_tmpl_type;
3838 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3839 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3841 pedwarn ("to refer to a type member of a template parameter, "
3842 "use %<typename %E%>", arg);
3844 arg = make_typename_type (TREE_OPERAND (arg, 0),
3845 TREE_OPERAND (arg, 1),
3846 complain & tf_error);
3849 if (is_type != requires_type)
3853 if (complain & tf_error)
3855 error ("type/value mismatch at argument %d in template "
3856 "parameter list for %qD",
3859 error (" expected a constant of type %qT, got %qT",
3861 (is_tmpl_type ? DECL_NAME (arg) : arg));
3862 else if (requires_tmpl_type)
3863 error (" expected a class template, got %qE", arg);
3865 error (" expected a type, got %qE", arg);
3868 return error_mark_node;
3870 if (is_tmpl_type ^ requires_tmpl_type)
3872 if (in_decl && (complain & tf_error))
3874 error ("type/value mismatch at argument %d in template "
3875 "parameter list for %qD",
3878 error (" expected a type, got %qT", DECL_NAME (arg));
3880 error (" expected a class template, got %qT", arg);
3882 return error_mark_node;
3887 if (requires_tmpl_type)
3889 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3890 /* The number of argument required is not known yet.
3891 Just accept it for now. */
3892 val = TREE_TYPE (arg);
3895 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3896 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3898 if (coerce_template_template_parms (parmparm, argparm,
3904 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3906 if (val != error_mark_node
3907 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3908 val = TREE_TYPE (val);
3912 if (in_decl && (complain & tf_error))
3914 error ("type/value mismatch at argument %d in "
3915 "template parameter list for %qD",
3917 error (" expected a template of type %qD, got %qD",
3921 val = error_mark_node;
3930 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3932 if (invalid_nontype_parm_type_p (t, complain))
3933 return error_mark_node;
3935 if (!uses_template_parms (arg) && !uses_template_parms (t))
3936 /* We used to call digest_init here. However, digest_init
3937 will report errors, which we don't want when complain
3938 is zero. More importantly, digest_init will try too
3939 hard to convert things: for example, `0' should not be
3940 converted to pointer type at this point according to
3941 the standard. Accepting this is not merely an
3942 extension, since deciding whether or not these
3943 conversions can occur is part of determining which
3944 function template to call, or whether a given explicit
3945 argument specification is valid. */
3946 val = convert_nontype_argument (t, arg);
3950 if (val == NULL_TREE)
3951 val = error_mark_node;
3952 else if (val == error_mark_node && (complain & tf_error))
3953 error ("could not convert template argument %qE to %qT", arg, t);
3959 /* Convert all template arguments to their appropriate types, and
3960 return a vector containing the innermost resulting template
3961 arguments. If any error occurs, return error_mark_node. Error and
3962 warning messages are issued under control of COMPLAIN.
3964 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3965 provided in ARGLIST, or else trailing parameters must have default
3966 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3967 deduction for any unspecified trailing arguments. */
3970 coerce_template_parms (tree parms,
3973 tsubst_flags_t complain,
3974 int require_all_arguments)
3976 int nparms, nargs, i, lost = 0;
3979 tree new_inner_args;
3981 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3982 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3983 nparms = TREE_VEC_LENGTH (parms);
3987 && require_all_arguments
3988 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3990 if (complain & tf_error)
3992 error ("wrong number of template arguments (%d, should be %d)",
3996 cp_error_at ("provided for %qD", in_decl);
3999 return error_mark_node;
4002 new_inner_args = make_tree_vec (nparms);
4003 new_args = add_outermost_template_args (args, new_inner_args);
4004 for (i = 0; i < nparms; i++)
4009 /* Get the Ith template parameter. */
4010 parm = TREE_VEC_ELT (parms, i);
4012 /* Calculate the Ith argument. */
4014 arg = TREE_VEC_ELT (inner_args, i);
4015 else if (require_all_arguments)
4016 /* There must be a default arg in this case. */
4017 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4023 if (arg == error_mark_node)
4024 error ("template argument %d is invalid", i + 1);
4026 arg = convert_template_argument (TREE_VALUE (parm),
4027 arg, new_args, complain, i,
4030 if (arg == error_mark_node)
4032 TREE_VEC_ELT (new_inner_args, i) = arg;
4036 return error_mark_node;
4038 return new_inner_args;
4041 /* Returns 1 if template args OT and NT are equivalent. */
4044 template_args_equal (tree ot, tree nt)
4049 if (TREE_CODE (nt) == TREE_VEC)
4050 /* For member templates */
4051 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4052 else if (TYPE_P (nt))
4053 return TYPE_P (ot) && same_type_p (ot, nt);
4054 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4057 return cp_tree_equal (ot, nt);
4060 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4061 of template arguments. Returns 0 otherwise. */
4064 comp_template_args (tree oldargs, tree newargs)
4068 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4071 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4073 tree nt = TREE_VEC_ELT (newargs, i);
4074 tree ot = TREE_VEC_ELT (oldargs, i);
4076 if (! template_args_equal (ot, nt))
4082 /* Given class template name and parameter list, produce a user-friendly name
4083 for the instantiation. */
4086 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4088 static struct obstack scratch_obstack;
4089 static char *scratch_firstobj;
4092 if (!scratch_firstobj)
4093 gcc_obstack_init (&scratch_obstack);
4095 obstack_free (&scratch_obstack, scratch_firstobj);
4096 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4098 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4099 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4103 nparms = TREE_VEC_LENGTH (parms);
4104 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4105 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4106 for (i = 0; i < nparms; i++)
4108 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4109 tree arg = TREE_VEC_ELT (arglist, i);
4114 if (TREE_CODE (parm) == TYPE_DECL)
4116 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4119 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4121 if (TREE_CODE (arg) == TEMPLATE_DECL)
4123 /* Already substituted with real template. Just output
4124 the template name here */
4125 tree context = DECL_CONTEXT (arg);
4128 /* The template may be defined in a namespace, or
4129 may be a member template. */
4130 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4131 || CLASS_TYPE_P (context));
4132 cat (decl_as_string (DECL_CONTEXT (arg),
4133 TFF_PLAIN_IDENTIFIER));
4136 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4139 /* Output the parameter declaration. */
4140 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4144 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4146 /* No need to check arglist against parmlist here; we did that
4147 in coerce_template_parms, called from lookup_template_class. */
4148 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4151 char *bufp = obstack_next_free (&scratch_obstack);
4153 while (bufp[offset - 1] == ' ')
4155 obstack_blank_fast (&scratch_obstack, offset);
4157 /* B<C<char> >, not B<C<char>> */
4158 if (bufp[offset - 1] == '>')
4163 return (char *) obstack_base (&scratch_obstack);
4167 classtype_mangled_name (tree t)
4169 if (CLASSTYPE_TEMPLATE_INFO (t)
4170 /* Specializations have already had their names set up in
4171 lookup_template_class. */
4172 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4174 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4176 /* For non-primary templates, the template parameters are
4177 implicit from their surrounding context. */
4178 if (PRIMARY_TEMPLATE_P (tmpl))
4180 tree name = DECL_NAME (tmpl);
4181 char *mangled_name = mangle_class_name_for_template
4182 (IDENTIFIER_POINTER (name),
4183 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4184 CLASSTYPE_TI_ARGS (t));
4185 tree id = get_identifier (mangled_name);
4186 IDENTIFIER_TEMPLATE (id) = name;
4191 return TYPE_IDENTIFIER (t);
4195 add_pending_template (tree d)
4197 tree ti = (TYPE_P (d)
4198 ? CLASSTYPE_TEMPLATE_INFO (d)
4199 : DECL_TEMPLATE_INFO (d));
4203 if (TI_PENDING_TEMPLATE_FLAG (ti))
4206 /* We are called both from instantiate_decl, where we've already had a
4207 tinst_level pushed, and instantiate_template, where we haven't.
4209 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4212 push_tinst_level (d);
4214 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4215 if (last_pending_template)
4216 TREE_CHAIN (last_pending_template) = pt;
4218 pending_templates = pt;
4220 last_pending_template = pt;
4222 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4229 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4230 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4231 documentation for TEMPLATE_ID_EXPR. */
4234 lookup_template_function (tree fns, tree arglist)
4238 if (fns == error_mark_node || arglist == error_mark_node)
4239 return error_mark_node;
4241 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4242 if (fns == NULL_TREE
4243 || TREE_CODE (fns) == FUNCTION_DECL)
4245 error ("non-template used as template");
4246 return error_mark_node;
4249 gcc_assert (TREE_CODE (fns) == TEMPLATE_DECL
4250 || TREE_CODE (fns) == OVERLOAD
4252 || TREE_CODE (fns) == IDENTIFIER_NODE);
4254 if (BASELINK_P (fns))
4256 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4258 BASELINK_FUNCTIONS (fns),
4263 type = TREE_TYPE (fns);
4264 if (TREE_CODE (fns) == OVERLOAD || !type)
4265 type = unknown_type_node;
4267 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4270 /* Within the scope of a template class S<T>, the name S gets bound
4271 (in build_self_reference) to a TYPE_DECL for the class, not a
4272 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4273 or one of its enclosing classes, and that type is a template,
4274 return the associated TEMPLATE_DECL. Otherwise, the original
4275 DECL is returned. */
4278 maybe_get_template_decl_from_type_decl (tree decl)
4280 return (decl != NULL_TREE
4281 && TREE_CODE (decl) == TYPE_DECL
4282 && DECL_ARTIFICIAL (decl)
4283 && CLASS_TYPE_P (TREE_TYPE (decl))
4284 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4285 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4288 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4289 parameters, find the desired type.
4291 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4293 IN_DECL, if non-NULL, is the template declaration we are trying to
4296 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4297 the class we are looking up.
4299 Issue error and warning messages under control of COMPLAIN.
4301 If the template class is really a local class in a template
4302 function, then the FUNCTION_CONTEXT is the function in which it is
4303 being instantiated. */
4306 lookup_template_class (tree d1,
4311 tsubst_flags_t complain)
4313 tree template = NULL_TREE, parmlist;
4316 timevar_push (TV_NAME_LOOKUP);
4318 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4320 tree value = innermost_non_namespace_value (d1);
4321 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4326 push_decl_namespace (context);
4327 template = lookup_name (d1, /*prefer_type=*/0);
4328 template = maybe_get_template_decl_from_type_decl (template);
4330 pop_decl_namespace ();
4333 context = DECL_CONTEXT (template);
4335 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4337 tree type = TREE_TYPE (d1);
4339 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4340 an implicit typename for the second A. Deal with it. */
4341 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4342 type = TREE_TYPE (type);
4344 if (CLASSTYPE_TEMPLATE_INFO (type))
4346 template = CLASSTYPE_TI_TEMPLATE (type);
4347 d1 = DECL_NAME (template);
4350 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4351 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4353 template = TYPE_TI_TEMPLATE (d1);
4354 d1 = DECL_NAME (template);
4356 else if (TREE_CODE (d1) == TEMPLATE_DECL
4357 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4360 d1 = DECL_NAME (template);
4361 context = DECL_CONTEXT (template);
4364 /* Issue an error message if we didn't find a template. */
4367 if (complain & tf_error)
4368 error ("%qT is not a template", d1);
4369 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4372 if (TREE_CODE (template) != TEMPLATE_DECL
4373 /* Make sure it's a user visible template, if it was named by
4375 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4376 && !PRIMARY_TEMPLATE_P (template)))
4378 if (complain & tf_error)
4380 error ("non-template type %qT used as a template", d1);
4382 cp_error_at ("for template declaration %qD", in_decl);
4384 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4387 complain &= ~tf_user;
4389 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4391 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4392 template arguments */
4397 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4399 /* Consider an example where a template template parameter declared as
4401 template <class T, class U = std::allocator<T> > class TT
4403 The template parameter level of T and U are one level larger than
4404 of TT. To proper process the default argument of U, say when an
4405 instantiation `TT<int>' is seen, we need to build the full
4406 arguments containing {int} as the innermost level. Outer levels,
4407 available when not appearing as default template argument, can be
4408 obtained from `current_template_args ()'.
4410 Suppose that TT is later substituted with std::vector. The above
4411 instantiation is `TT<int, std::allocator<T> >' with TT at
4412 level 1, and T at level 2, while the template arguments at level 1
4413 becomes {std::vector} and the inner level 2 is {int}. */
4415 if (current_template_parms)
4416 arglist = add_to_template_args (current_template_args (), arglist);
4418 arglist2 = coerce_template_parms (parmlist, arglist, template,
4419 complain, /*require_all_args=*/1);
4420 if (arglist2 == error_mark_node
4421 || (!uses_template_parms (arglist2)
4422 && check_instantiated_args (template, arglist2, complain)))
4423 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4425 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4426 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4430 tree template_type = TREE_TYPE (template);
4433 tree found = NULL_TREE;
4436 int is_partial_instantiation;
4438 gen_tmpl = most_general_template (template);
4439 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4440 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4441 arg_depth = TMPL_ARGS_DEPTH (arglist);
4443 if (arg_depth == 1 && parm_depth > 1)
4445 /* We've been given an incomplete set of template arguments.
4448 template <class T> struct S1 {
4449 template <class U> struct S2 {};
4450 template <class U> struct S2<U*> {};
4453 we will be called with an ARGLIST of `U*', but the
4454 TEMPLATE will be `template <class T> template
4455 <class U> struct S1<T>::S2'. We must fill in the missing
4458 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4460 arg_depth = TMPL_ARGS_DEPTH (arglist);
4463 /* Now we should have enough arguments. */
4464 gcc_assert (parm_depth == arg_depth);
4466 /* From here on, we're only interested in the most general
4468 template = gen_tmpl;
4470 /* Calculate the BOUND_ARGS. These will be the args that are
4471 actually tsubst'd into the definition to create the
4475 /* We have multiple levels of arguments to coerce, at once. */
4477 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4479 tree bound_args = make_tree_vec (parm_depth);
4481 for (i = saved_depth,
4482 t = DECL_TEMPLATE_PARMS (template);
4483 i > 0 && t != NULL_TREE;
4484 --i, t = TREE_CHAIN (t))
4486 tree a = coerce_template_parms (TREE_VALUE (t),
4488 complain, /*require_all_args=*/1);
4490 /* Don't process further if one of the levels fails. */
4491 if (a == error_mark_node)
4493 /* Restore the ARGLIST to its full size. */
4494 TREE_VEC_LENGTH (arglist) = saved_depth;
4495 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4498 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4500 /* We temporarily reduce the length of the ARGLIST so
4501 that coerce_template_parms will see only the arguments
4502 corresponding to the template parameters it is
4504 TREE_VEC_LENGTH (arglist)--;
4507 /* Restore the ARGLIST to its full size. */
4508 TREE_VEC_LENGTH (arglist) = saved_depth;
4510 arglist = bound_args;
4514 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4515 INNERMOST_TEMPLATE_ARGS (arglist),
4517 complain, /*require_all_args=*/1);
4519 if (arglist == error_mark_node)
4520 /* We were unable to bind the arguments. */
4521 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4523 /* In the scope of a template class, explicit references to the
4524 template class refer to the type of the template, not any
4525 instantiation of it. For example, in:
4527 template <class T> class C { void f(C<T>); }
4529 the `C<T>' is just the same as `C'. Outside of the
4530 class, however, such a reference is an instantiation. */
4531 if (comp_template_args (TYPE_TI_ARGS (template_type),
4534 found = template_type;
4536 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4540 for (ctx = current_class_type;
4541 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4543 ? TYPE_CONTEXT (ctx)
4544 : DECL_CONTEXT (ctx)))
4545 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4548 /* We're not in the scope of the class, so the
4549 TEMPLATE_TYPE is not the type we want after all. */
4555 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4557 /* If we already have this specialization, return it. */
4558 found = retrieve_specialization (template, arglist,
4559 /*class_specializations_p=*/false);
4561 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4563 /* This type is a "partial instantiation" if any of the template
4564 arguments still involve template parameters. Note that we set
4565 IS_PARTIAL_INSTANTIATION for partial specializations as
4567 is_partial_instantiation = uses_template_parms (arglist);
4569 /* If the deduced arguments are invalid, then the binding
4571 if (!is_partial_instantiation
4572 && check_instantiated_args (template,
4573 INNERMOST_TEMPLATE_ARGS (arglist),
4575 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4577 if (!is_partial_instantiation
4578 && !PRIMARY_TEMPLATE_P (template)
4579 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4581 found = xref_tag_from_type (TREE_TYPE (template),
4582 DECL_NAME (template),
4584 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4587 context = tsubst (DECL_CONTEXT (template), arglist,
4590 context = global_namespace;
4592 /* Create the type. */
4593 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4595 if (!is_partial_instantiation)
4597 set_current_access_from_decl (TYPE_NAME (template_type));
4598 t = start_enum (TYPE_IDENTIFIER (template_type));
4601 /* We don't want to call start_enum for this type, since
4602 the values for the enumeration constants may involve
4603 template parameters. And, no one should be interested
4604 in the enumeration constants for such a type. */
4605 t = make_node (ENUMERAL_TYPE);
4609 t = make_aggr_type (TREE_CODE (template_type));
4610 CLASSTYPE_DECLARED_CLASS (t)
4611 = CLASSTYPE_DECLARED_CLASS (template_type);
4612 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4613 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4615 /* A local class. Make sure the decl gets registered properly. */
4616 if (context == current_function_decl)
4617 pushtag (DECL_NAME (template), t, 0);
4620 /* If we called start_enum or pushtag above, this information
4621 will already be set up. */
4624 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4626 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4627 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4628 TYPE_STUB_DECL (t) = type_decl;
4629 DECL_SOURCE_LOCATION (type_decl)
4630 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4633 type_decl = TYPE_NAME (t);
4635 TREE_PRIVATE (type_decl)
4636 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4637 TREE_PROTECTED (type_decl)
4638 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4640 /* Set up the template information. We have to figure out which
4641 template is the immediate parent if this is a full
4643 if (parm_depth == 1 || is_partial_instantiation
4644 || !PRIMARY_TEMPLATE_P (template))
4645 /* This case is easy; there are no member templates involved. */
4649 /* This is a full instantiation of a member template. Look
4650 for a partial instantiation of which this is an instance. */
4652 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4653 found; found = TREE_CHAIN (found))
4656 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4658 /* We only want partial instantiations, here, not
4659 specializations or full instantiations. */
4660 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4661 || !uses_template_parms (TREE_VALUE (found)))
4664 /* Temporarily reduce by one the number of levels in the
4665 ARGLIST and in FOUND so as to avoid comparing the
4666 last set of arguments. */
4667 TREE_VEC_LENGTH (arglist)--;
4668 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4670 /* See if the arguments match. If they do, then TMPL is
4671 the partial instantiation we want. */
4672 success = comp_template_args (TREE_PURPOSE (found), arglist);
4674 /* Restore the argument vectors to their full size. */
4675 TREE_VEC_LENGTH (arglist)++;
4676 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4687 /* There was no partial instantiation. This happens
4688 where C<T> is a member template of A<T> and it's used
4691 template <typename T> struct B { A<T>::C<int> m; };
4694 Create the partial instantiation.
4696 TREE_VEC_LENGTH (arglist)--;
4697 found = tsubst (template, arglist, complain, NULL_TREE);
4698 TREE_VEC_LENGTH (arglist)++;
4702 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4703 DECL_TEMPLATE_INSTANTIATIONS (template)
4704 = tree_cons (arglist, t,
4705 DECL_TEMPLATE_INSTANTIATIONS (template));
4707 if (TREE_CODE (t) == ENUMERAL_TYPE
4708 && !is_partial_instantiation)
4709 /* Now that the type has been registered on the instantiations
4710 list, we set up the enumerators. Because the enumeration
4711 constants may involve the enumeration type itself, we make
4712 sure to register the type first, and then create the
4713 constants. That way, doing tsubst_expr for the enumeration
4714 constants won't result in recursive calls here; we'll find
4715 the instantiation and exit above. */
4716 tsubst_enum (template_type, t, arglist);
4718 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4720 if (TREE_CODE (t) != ENUMERAL_TYPE)
4721 DECL_NAME (type_decl) = classtype_mangled_name (t);
4722 if (is_partial_instantiation)
4723 /* If the type makes use of template parameters, the
4724 code that generates debugging information will crash. */
4725 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4727 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4729 timevar_pop (TV_NAME_LOOKUP);
4736 struct pointer_set_t *visited;
4739 /* Called from for_each_template_parm via walk_tree. */
4742 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4745 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4746 tree_fn_t fn = pfd->fn;
4747 void *data = pfd->data;
4750 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4751 return error_mark_node;
4753 switch (TREE_CODE (t))
4756 if (TYPE_PTRMEMFUNC_P (t))
4762 if (!TYPE_TEMPLATE_INFO (t))
4764 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4765 fn, data, pfd->visited))
4766 return error_mark_node;
4770 /* Since we're not going to walk subtrees, we have to do this
4772 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4774 return error_mark_node;
4778 /* Check the return type. */
4779 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4780 return error_mark_node;
4782 /* Check the parameter types. Since default arguments are not
4783 instantiated until they are needed, the TYPE_ARG_TYPES may
4784 contain expressions that involve template parameters. But,
4785 no-one should be looking at them yet. And, once they're
4786 instantiated, they don't contain template parameters, so
4787 there's no point in looking at them then, either. */
4791 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4792 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4794 return error_mark_node;
4796 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4797 want walk_tree walking into them itself. */
4803 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4805 return error_mark_node;
4810 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4811 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4813 return error_mark_node;
4818 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4819 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4821 return error_mark_node;
4822 if (DECL_CONTEXT (t)
4823 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4825 return error_mark_node;
4828 case BOUND_TEMPLATE_TEMPLATE_PARM:
4829 /* Record template parameters such as `T' inside `TT<T>'. */
4830 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4831 return error_mark_node;
4834 case TEMPLATE_TEMPLATE_PARM:
4835 case TEMPLATE_TYPE_PARM:
4836 case TEMPLATE_PARM_INDEX:
4837 if (fn && (*fn)(t, data))
4838 return error_mark_node;
4840 return error_mark_node;
4844 /* A template template parameter is encountered. */
4845 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4846 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4847 return error_mark_node;
4849 /* Already substituted template template parameter */
4855 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4856 data, pfd->visited))
4857 return error_mark_node;
4861 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4862 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4863 (TREE_TYPE (t)), fn, data,
4865 return error_mark_node;
4870 /* If there's no type, then this thing must be some expression
4871 involving template parameters. */
4872 if (!fn && !TREE_TYPE (t))
4873 return error_mark_node;
4878 case REINTERPRET_CAST_EXPR:
4879 case CONST_CAST_EXPR:
4880 case STATIC_CAST_EXPR:
4881 case DYNAMIC_CAST_EXPR:
4885 case PSEUDO_DTOR_EXPR:
4887 return error_mark_node;
4891 /* If we do not handle this case specially, we end up walking
4892 the BINFO hierarchy, which is circular, and therefore
4893 confuses walk_tree. */
4895 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4897 return error_mark_node;
4904 /* We didn't find any template parameters we liked. */
4908 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4909 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4910 call FN with the parameter and the DATA.
4911 If FN returns nonzero, the iteration is terminated, and
4912 for_each_template_parm returns 1. Otherwise, the iteration
4913 continues. If FN never returns a nonzero value, the value
4914 returned by for_each_template_parm is 0. If FN is NULL, it is
4915 considered to be the function which always returns 1. */
4918 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4919 struct pointer_set_t *visited)
4921 struct pair_fn_data pfd;
4928 /* Walk the tree. (Conceptually, we would like to walk without
4929 duplicates, but for_each_template_parm_r recursively calls
4930 for_each_template_parm, so we would need to reorganize a fair
4931 bit to use walk_tree_without_duplicates, so we keep our own
4934 pfd.visited = visited;
4936 pfd.visited = pointer_set_create ();
4937 result = walk_tree (&t,
4938 for_each_template_parm_r,
4940 pfd.visited) != NULL_TREE;
4945 pointer_set_destroy (pfd.visited);
4952 /* Returns true if T depends on any template parameter. */
4955 uses_template_parms (tree t)
4958 int saved_processing_template_decl;
4960 saved_processing_template_decl = processing_template_decl;
4961 if (!saved_processing_template_decl)
4962 processing_template_decl = 1;
4964 dependent_p = dependent_type_p (t);
4965 else if (TREE_CODE (t) == TREE_VEC)
4966 dependent_p = any_dependent_template_arguments_p (t);
4967 else if (TREE_CODE (t) == TREE_LIST)
4968 dependent_p = (uses_template_parms (TREE_VALUE (t))
4969 || uses_template_parms (TREE_CHAIN (t)));
4972 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4973 || TREE_CODE (t) == OVERLOAD
4974 || TREE_CODE (t) == BASELINK
4975 || CONSTANT_CLASS_P (t))
4976 dependent_p = (type_dependent_expression_p (t)
4977 || value_dependent_expression_p (t));
4980 gcc_assert (t == error_mark_node);
4981 dependent_p = false;
4984 processing_template_decl = saved_processing_template_decl;
4989 /* Returns true if T depends on any template parameter with level LEVEL. */
4992 uses_template_parms_level (tree t, int level)
4994 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4997 static int tinst_depth;
4998 extern int max_tinst_depth;
4999 #ifdef GATHER_STATISTICS
5002 static int tinst_level_tick;
5003 static int last_template_error_tick;
5005 /* We're starting to instantiate D; record the template instantiation context
5006 for diagnostics and to restore it later. */
5009 push_tinst_level (tree d)
5013 if (tinst_depth >= max_tinst_depth)
5015 /* If the instantiation in question still has unbound template parms,
5016 we don't really care if we can't instantiate it, so just return.
5017 This happens with base instantiation for implicit `typename'. */
5018 if (uses_template_parms (d))
5021 last_template_error_tick = tinst_level_tick;
5022 error ("template instantiation depth exceeds maximum of %d (use "
5023 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5024 max_tinst_depth, d);
5026 print_instantiation_context ();
5031 new = make_tinst_level (d, input_location);
5032 TREE_CHAIN (new) = current_tinst_level;
5033 current_tinst_level = new;
5036 #ifdef GATHER_STATISTICS
5037 if (tinst_depth > depth_reached)
5038 depth_reached = tinst_depth;
5045 /* We're done instantiating this template; return to the instantiation
5049 pop_tinst_level (void)
5051 tree old = current_tinst_level;
5053 /* Restore the filename and line number stashed away when we started
5054 this instantiation. */
5055 input_location = TINST_LOCATION (old);
5056 current_tinst_level = TREE_CHAIN (old);
5061 /* We're instantiating a deferred template; restore the template
5062 instantiation context in which the instantiation was requested, which
5063 is one step out from LEVEL. */
5066 reopen_tinst_level (tree level)
5071 for (t = level; t; t = TREE_CHAIN (t))
5074 current_tinst_level = level;
5078 /* Return the outermost template instantiation context, for use with
5079 -falt-external-templates. */
5082 tinst_for_decl (void)
5084 tree p = current_tinst_level;
5087 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
5092 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5093 vector of template arguments, as for tsubst.
5095 Returns an appropriate tsubst'd friend declaration. */
5098 tsubst_friend_function (tree decl, tree args)
5101 location_t saved_loc = input_location;
5103 input_location = DECL_SOURCE_LOCATION (decl);
5105 if (TREE_CODE (decl) == FUNCTION_DECL
5106 && DECL_TEMPLATE_INSTANTIATION (decl)
5107 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5108 /* This was a friend declared with an explicit template
5109 argument list, e.g.:
5113 to indicate that f was a template instantiation, not a new
5114 function declaration. Now, we have to figure out what
5115 instantiation of what template. */
5117 tree template_id, arglist, fns;
5120 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5122 /* Friend functions are looked up in the containing namespace scope.
5123 We must enter that scope, to avoid finding member functions of the
5124 current cless with same name. */
5125 push_nested_namespace (ns);
5126 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5127 tf_error | tf_warning, NULL_TREE);
5128 pop_nested_namespace (ns);
5129 arglist = tsubst (DECL_TI_ARGS (decl), args,
5130 tf_error | tf_warning, NULL_TREE);
5131 template_id = lookup_template_function (fns, arglist);
5133 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5134 tmpl = determine_specialization (template_id, new_friend,
5136 /*need_member_template=*/0,
5137 TREE_VEC_LENGTH (args));
5138 new_friend = instantiate_template (tmpl, new_args, tf_error);
5142 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5144 /* The NEW_FRIEND will look like an instantiation, to the
5145 compiler, but is not an instantiation from the point of view of
5146 the language. For example, we might have had:
5148 template <class T> struct S {
5149 template <class U> friend void f(T, U);
5152 Then, in S<int>, template <class U> void f(int, U) is not an
5153 instantiation of anything. */
5154 if (new_friend == error_mark_node)
5155 return error_mark_node;
5157 DECL_USE_TEMPLATE (new_friend) = 0;
5158 if (TREE_CODE (decl) == TEMPLATE_DECL)
5160 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5161 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5162 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5165 /* The mangled name for the NEW_FRIEND is incorrect. The function
5166 is not a template instantiation and should not be mangled like
5167 one. Therefore, we forget the mangling here; we'll recompute it
5168 later if we need it. */
5169 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5171 SET_DECL_RTL (new_friend, NULL_RTX);
5172 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5175 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5178 tree new_friend_template_info;
5179 tree new_friend_result_template_info;
5181 int new_friend_is_defn;
5183 /* We must save some information from NEW_FRIEND before calling
5184 duplicate decls since that function will free NEW_FRIEND if
5186 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5187 new_friend_is_defn =
5188 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5189 (template_for_substitution (new_friend)))
5191 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5193 /* This declaration is a `primary' template. */
5194 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5196 new_friend_result_template_info
5197 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5200 new_friend_result_template_info = NULL_TREE;
5202 /* Inside pushdecl_namespace_level, we will push into the
5203 current namespace. However, the friend function should go
5204 into the namespace of the template. */
5205 ns = decl_namespace_context (new_friend);
5206 push_nested_namespace (ns);
5207 old_decl = pushdecl_namespace_level (new_friend);
5208 pop_nested_namespace (ns);
5210 if (old_decl != new_friend)
5212 /* This new friend declaration matched an existing
5213 declaration. For example, given:
5215 template <class T> void f(T);
5216 template <class U> class C {
5217 template <class T> friend void f(T) {}
5220 the friend declaration actually provides the definition
5221 of `f', once C has been instantiated for some type. So,
5222 old_decl will be the out-of-class template declaration,
5223 while new_friend is the in-class definition.
5225 But, if `f' was called before this point, the
5226 instantiation of `f' will have DECL_TI_ARGS corresponding
5227 to `T' but not to `U', references to which might appear
5228 in the definition of `f'. Previously, the most general
5229 template for an instantiation of `f' was the out-of-class
5230 version; now it is the in-class version. Therefore, we
5231 run through all specialization of `f', adding to their
5232 DECL_TI_ARGS appropriately. In particular, they need a
5233 new set of outer arguments, corresponding to the
5234 arguments for this class instantiation.
5236 The same situation can arise with something like this:
5239 template <class T> class C {
5243 when `C<int>' is instantiated. Now, `f(int)' is defined
5246 if (!new_friend_is_defn)
5247 /* On the other hand, if the in-class declaration does
5248 *not* provide a definition, then we don't want to alter
5249 existing definitions. We can just leave everything
5254 /* Overwrite whatever template info was there before, if
5255 any, with the new template information pertaining to
5257 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5259 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5260 reregister_specialization (new_friend,
5261 most_general_template (old_decl),
5266 tree new_friend_args;
5268 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5269 = new_friend_result_template_info;
5271 new_friend_args = TI_ARGS (new_friend_template_info);
5272 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5276 tree spec = TREE_VALUE (t);
5279 = add_outermost_template_args (new_friend_args,
5280 DECL_TI_ARGS (spec));
5283 /* Now, since specializations are always supposed to
5284 hang off of the most general template, we must move
5286 t = most_general_template (old_decl);
5289 DECL_TEMPLATE_SPECIALIZATIONS (t)
5290 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5291 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5292 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5297 /* The information from NEW_FRIEND has been merged into OLD_DECL
5298 by duplicate_decls. */
5299 new_friend = old_decl;
5302 else if (COMPLETE_TYPE_P (DECL_CONTEXT (new_friend)))
5304 /* Check to see that the declaration is really present, and,
5305 possibly obtain an improved declaration. */
5306 tree fn = check_classfn (DECL_CONTEXT (new_friend),
5307 new_friend, NULL_TREE);
5314 input_location = saved_loc;
5318 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5319 template arguments, as for tsubst.
5321 Returns an appropriate tsubst'd friend type or error_mark_node on
5325 tsubst_friend_class (tree friend_tmpl, tree args)
5331 context = DECL_CONTEXT (friend_tmpl);
5335 if (TREE_CODE (context) == NAMESPACE_DECL)
5336 push_nested_namespace (context);
5338 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5341 /* First, we look for a class template. */
5342 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5344 /* But, if we don't find one, it might be because we're in a
5345 situation like this:
5353 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5354 for `S<int>', not the TEMPLATE_DECL. */
5355 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5357 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5358 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5361 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5363 /* The friend template has already been declared. Just
5364 check to see that the declarations match, and install any new
5365 default parameters. We must tsubst the default parameters,
5366 of course. We only need the innermost template parameters
5367 because that is all that redeclare_class_template will look
5369 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5370 > TMPL_ARGS_DEPTH (args))
5373 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5374 args, tf_error | tf_warning);
5375 redeclare_class_template (TREE_TYPE (tmpl), parms);
5378 friend_type = TREE_TYPE (tmpl);
5382 /* The friend template has not already been declared. In this
5383 case, the instantiation of the template class will cause the
5384 injection of this template into the global scope. */
5385 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5387 /* The new TMPL is not an instantiation of anything, so we
5388 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5389 the new type because that is supposed to be the corresponding
5390 template decl, i.e., TMPL. */
5391 DECL_USE_TEMPLATE (tmpl) = 0;
5392 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5393 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5394 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5395 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5397 /* Inject this template into the global scope. */
5398 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5403 if (TREE_CODE (context) == NAMESPACE_DECL)
5404 pop_nested_namespace (context);
5406 pop_nested_class ();
5412 /* Returns zero if TYPE cannot be completed later due to circularity.
5413 Otherwise returns one. */
5416 can_complete_type_without_circularity (tree type)
5418 if (type == NULL_TREE || type == error_mark_node)
5420 else if (COMPLETE_TYPE_P (type))
5422 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5423 return can_complete_type_without_circularity (TREE_TYPE (type));
5424 else if (CLASS_TYPE_P (type)
5425 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5432 instantiate_class_template (tree type)
5434 tree template, args, pattern, t, member;
5439 if (type == error_mark_node)
5440 return error_mark_node;
5442 if (TYPE_BEING_DEFINED (type)
5443 || COMPLETE_TYPE_P (type)
5444 || dependent_type_p (type))
5447 /* Figure out which template is being instantiated. */
5448 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5449 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5451 /* Figure out which arguments are being used to do the
5453 args = CLASSTYPE_TI_ARGS (type);
5455 /* Determine what specialization of the original template to
5457 t = most_specialized_class (template, args);
5458 if (t == error_mark_node)
5460 const char *str = "candidates are:";
5461 error ("ambiguous class template instantiation for %q#T", type);
5462 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5465 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5467 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5471 TYPE_BEING_DEFINED (type) = 1;
5472 return error_mark_node;
5476 pattern = TREE_TYPE (t);
5478 pattern = TREE_TYPE (template);
5480 /* If the template we're instantiating is incomplete, then clearly
5481 there's nothing we can do. */
5482 if (!COMPLETE_TYPE_P (pattern))
5485 /* If we've recursively instantiated too many templates, stop. */
5486 if (! push_tinst_level (type))
5489 /* Now we're really doing the instantiation. Mark the type as in
5490 the process of being defined. */
5491 TYPE_BEING_DEFINED (type) = 1;
5493 /* We may be in the middle of deferred access check. Disable
5495 push_deferring_access_checks (dk_no_deferred);
5497 push_to_top_level ();
5501 /* This TYPE is actually an instantiation of a partial
5502 specialization. We replace the innermost set of ARGS with
5503 the arguments appropriate for substitution. For example,
5506 template <class T> struct S {};
5507 template <class T> struct S<T*> {};
5509 and supposing that we are instantiating S<int*>, ARGS will
5510 present be {int*} but we need {int}. */
5512 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5515 /* If there were multiple levels in ARGS, replacing the
5516 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5517 want, so we make a copy first. */
5518 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5520 args = copy_node (args);
5521 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5527 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5529 /* Set the input location to the template definition. This is needed
5530 if tsubsting causes an error. */
5531 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (pattern));
5533 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5534 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5535 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5536 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5537 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5538 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5539 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5540 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5541 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5542 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5543 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5544 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5545 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5546 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5547 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5548 if (ANON_AGGR_TYPE_P (pattern))
5549 SET_ANON_AGGR_TYPE_P (type);
5551 pbinfo = TYPE_BINFO (pattern);
5553 /* We should never instantiate a nested class before its enclosing
5554 class; we need to look up the nested class by name before we can
5555 instantiate it, and that lookup should instantiate the enclosing
5557 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5558 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5559 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5561 base_list = NULL_TREE;
5562 if (BINFO_N_BASE_BINFOS (pbinfo))
5565 tree context = TYPE_CONTEXT (type);
5569 /* We must enter the scope containing the type, as that is where
5570 the accessibility of types named in dependent bases are
5572 pop_p = push_scope (context ? context : global_namespace);
5574 /* Substitute into each of the bases to determine the actual
5576 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5579 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5581 /* Substitute to figure out the base class. */
5582 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5583 if (base == error_mark_node)
5586 base_list = tree_cons (access, base, base_list);
5587 if (BINFO_VIRTUAL_P (pbase_binfo))
5588 TREE_TYPE (base_list) = integer_type_node;
5591 /* The list is now in reverse order; correct that. */
5592 base_list = nreverse (base_list);
5595 pop_scope (context ? context : global_namespace);
5597 /* Now call xref_basetypes to set up all the base-class
5599 xref_basetypes (type, base_list);
5602 /* Now that our base classes are set up, enter the scope of the
5603 class, so that name lookups into base classes, etc. will work
5604 correctly. This is precisely analogous to what we do in
5605 begin_class_definition when defining an ordinary non-template
5609 /* Now members are processed in the order of declaration. */
5610 for (member = CLASSTYPE_DECL_LIST (pattern);
5611 member; member = TREE_CHAIN (member))
5613 tree t = TREE_VALUE (member);
5615 if (TREE_PURPOSE (member))
5619 /* Build new CLASSTYPE_NESTED_UTDS. */
5622 tree name = TYPE_IDENTIFIER (tag);
5625 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5626 if (newtag == error_mark_node)
5629 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5631 if (TYPE_LANG_SPECIFIC (tag) && CLASSTYPE_IS_TEMPLATE (tag))
5632 /* Unfortunately, lookup_template_class sets
5633 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5634 instantiation (i.e., for the type of a member
5635 template class nested within a template class.)
5636 This behavior is required for
5637 maybe_process_partial_specialization to work
5638 correctly, but is not accurate in this case;
5639 the TAG is not an instantiation of anything.
5640 (The corresponding TEMPLATE_DECL is an
5641 instantiation, but the TYPE is not.) */
5642 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5644 /* Now, we call pushtag to put this NEWTAG into the scope of
5645 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5646 pushtag calling push_template_decl. We don't have to do
5647 this for enums because it will already have been done in
5650 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5651 pushtag (name, newtag, /*globalize=*/0);
5654 else if (TREE_CODE (t) == FUNCTION_DECL
5655 || DECL_FUNCTION_TEMPLATE_P (t))
5657 /* Build new TYPE_METHODS. */
5660 if (TREE_CODE (t) == TEMPLATE_DECL)
5661 ++processing_template_decl;
5662 r = tsubst (t, args, tf_error, NULL_TREE);
5663 if (TREE_CODE (t) == TEMPLATE_DECL)
5664 --processing_template_decl;
5665 set_current_access_from_decl (r);
5666 grok_special_member_properties (r);
5667 finish_member_declaration (r);
5671 /* Build new TYPE_FIELDS. */
5673 if (TREE_CODE (t) != CONST_DECL)
5677 /* The the file and line for this declaration, to
5678 assist in error message reporting. Since we
5679 called push_tinst_level above, we don't need to
5681 input_location = DECL_SOURCE_LOCATION (t);
5683 if (TREE_CODE (t) == TEMPLATE_DECL)
5684 ++processing_template_decl;
5685 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5686 if (TREE_CODE (t) == TEMPLATE_DECL)
5687 --processing_template_decl;
5688 if (TREE_CODE (r) == VAR_DECL)
5692 if (DECL_INITIALIZED_IN_CLASS_P (r))
5693 init = tsubst_expr (DECL_INITIAL (t), args,
5694 tf_error | tf_warning, NULL_TREE);
5698 finish_static_data_member_decl
5699 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5701 if (DECL_INITIALIZED_IN_CLASS_P (r))
5702 check_static_variable_definition (r, TREE_TYPE (r));
5704 else if (TREE_CODE (r) == FIELD_DECL)
5706 /* Determine whether R has a valid type and can be
5707 completed later. If R is invalid, then it is
5708 replaced by error_mark_node so that it will not be
5709 added to TYPE_FIELDS. */
5710 tree rtype = TREE_TYPE (r);
5711 if (can_complete_type_without_circularity (rtype))
5712 complete_type (rtype);
5714 if (!COMPLETE_TYPE_P (rtype))
5716 cxx_incomplete_type_error (r, rtype);
5717 r = error_mark_node;
5721 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5722 such a thing will already have been added to the field
5723 list by tsubst_enum in finish_member_declaration in the
5724 CLASSTYPE_NESTED_UTDS case above. */
5725 if (!(TREE_CODE (r) == TYPE_DECL
5726 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5727 && DECL_ARTIFICIAL (r)))
5729 set_current_access_from_decl (r);
5730 finish_member_declaration (r);
5737 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5739 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5741 tree friend_type = t;
5742 bool adjust_processing_template_decl = false;
5744 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5746 friend_type = tsubst_friend_class (friend_type, args);
5747 adjust_processing_template_decl = true;
5749 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5751 friend_type = tsubst (friend_type, args,
5752 tf_error | tf_warning, NULL_TREE);
5753 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5754 friend_type = TREE_TYPE (friend_type);
5755 adjust_processing_template_decl = true;
5757 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5759 friend_type = tsubst (friend_type, args,
5760 tf_error | tf_warning, NULL_TREE);
5761 /* Bump processing_template_decl for correct
5762 dependent_type_p calculation. */
5763 ++processing_template_decl;
5764 if (dependent_type_p (friend_type))
5765 adjust_processing_template_decl = true;
5766 --processing_template_decl;
5768 else if (uses_template_parms (friend_type))
5769 friend_type = tsubst (friend_type, args,
5770 tf_error | tf_warning, NULL_TREE);
5771 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5772 friend_type = friend_type;
5775 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5777 /* The call to xref_tag_from_type does injection for friend
5779 push_nested_namespace (ns);
5781 xref_tag_from_type (friend_type, NULL_TREE, 1);
5782 pop_nested_namespace (ns);
5785 if (adjust_processing_template_decl)
5786 /* Trick make_friend_class into realizing that the friend
5787 we're adding is a template, not an ordinary class. It's
5788 important that we use make_friend_class since it will
5789 perform some error-checking and output cross-reference
5791 ++processing_template_decl;
5793 if (friend_type != error_mark_node)
5794 make_friend_class (type, friend_type, /*complain=*/false);
5796 if (adjust_processing_template_decl)
5797 --processing_template_decl;
5801 /* Build new DECL_FRIENDLIST. */
5804 if (TREE_CODE (t) == TEMPLATE_DECL)
5806 ++processing_template_decl;
5807 push_deferring_access_checks (dk_no_check);
5810 r = tsubst_friend_function (t, args);
5811 add_friend (type, r, /*complain=*/false);
5812 if (TREE_CODE (t) == TEMPLATE_DECL)
5814 pop_deferring_access_checks ();
5815 --processing_template_decl;
5821 /* Set the file and line number information to whatever is given for
5822 the class itself. This puts error messages involving generated
5823 implicit functions at a predictable point, and the same point
5824 that would be used for non-template classes. */
5825 typedecl = TYPE_MAIN_DECL (type);
5826 input_location = DECL_SOURCE_LOCATION (typedecl);
5828 unreverse_member_declarations (type);
5829 finish_struct_1 (type);
5830 TYPE_BEING_DEFINED (type) = 0;
5832 /* Now that the class is complete, instantiate default arguments for
5833 any member functions. We don't do this earlier because the
5834 default arguments may reference members of the class. */
5835 if (!PRIMARY_TEMPLATE_P (template))
5836 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5837 if (TREE_CODE (t) == FUNCTION_DECL
5838 /* Implicitly generated member functions will not have template
5839 information; they are not instantiations, but instead are
5840 created "fresh" for each instantiation. */
5841 && DECL_TEMPLATE_INFO (t))
5842 tsubst_default_arguments (t);
5845 pop_from_top_level ();
5846 pop_deferring_access_checks ();
5849 /* The vtable for a template class can be emitted in any translation
5850 unit in which the class is instantiated. When there is no key
5851 method, however, finish_struct_1 will already have added TYPE to
5852 the keyed_classes list. */
5853 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5854 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5860 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5866 else if (TYPE_P (t))
5867 r = tsubst (t, args, complain, in_decl);
5870 r = tsubst_expr (t, args, complain, in_decl);
5872 if (!uses_template_parms (r))
5874 /* Sometimes, one of the args was an expression involving a
5875 template constant parameter, like N - 1. Now that we've
5876 tsubst'd, we might have something like 2 - 1. This will
5877 confuse lookup_template_class, so we do constant folding
5878 here. We have to unset processing_template_decl, to fool
5879 tsubst_copy_and_build() into building an actual tree. */
5881 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5882 as simple as it's going to get, and trying to reprocess
5883 the trees will break. Once tsubst_expr et al DTRT for
5884 non-dependent exprs, this code can go away, as the type
5885 will always be set. */
5888 int saved_processing_template_decl = processing_template_decl;
5889 processing_template_decl = 0;
5890 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5891 tf_error, /*in_decl=*/NULL_TREE,
5892 /*function_p=*/false);
5893 processing_template_decl = saved_processing_template_decl;
5901 /* Substitute ARGS into the vector or list of template arguments T. */
5904 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5906 int len = TREE_VEC_LENGTH (t);
5907 int need_new = 0, i;
5908 tree *elts = alloca (len * sizeof (tree));
5910 for (i = 0; i < len; i++)
5912 tree orig_arg = TREE_VEC_ELT (t, i);
5915 if (TREE_CODE (orig_arg) == TREE_VEC)
5916 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5918 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5920 if (new_arg == error_mark_node)
5921 return error_mark_node;
5924 if (new_arg != orig_arg)
5931 t = make_tree_vec (len);
5932 for (i = 0; i < len; i++)
5933 TREE_VEC_ELT (t, i) = elts[i];
5938 /* Return the result of substituting ARGS into the template parameters
5939 given by PARMS. If there are m levels of ARGS and m + n levels of
5940 PARMS, then the result will contain n levels of PARMS. For
5941 example, if PARMS is `template <class T> template <class U>
5942 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5943 result will be `template <int*, double, class V>'. */
5946 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5951 for (new_parms = &r;
5952 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5953 new_parms = &(TREE_CHAIN (*new_parms)),
5954 parms = TREE_CHAIN (parms))
5957 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5960 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5962 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5963 tree default_value = TREE_PURPOSE (tuple);
5964 tree parm_decl = TREE_VALUE (tuple);
5966 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5967 default_value = tsubst_template_arg (default_value, args,
5968 complain, NULL_TREE);
5970 tuple = build_tree_list (default_value, parm_decl);
5971 TREE_VEC_ELT (new_vec, i) = tuple;
5975 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
5976 - TMPL_ARGS_DEPTH (args)),
5977 new_vec, NULL_TREE);
5983 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5984 type T. If T is not an aggregate or enumeration type, it is
5985 handled as if by tsubst. IN_DECL is as for tsubst. If
5986 ENTERING_SCOPE is nonzero, T is the context for a template which
5987 we are presently tsubst'ing. Return the substituted value. */
5990 tsubst_aggr_type (tree t,
5992 tsubst_flags_t complain,
5999 switch (TREE_CODE (t))
6002 if (TYPE_PTRMEMFUNC_P (t))
6003 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6005 /* Else fall through. */
6008 if (TYPE_TEMPLATE_INFO (t))
6014 /* First, determine the context for the type we are looking
6016 context = TYPE_CONTEXT (t);
6018 context = tsubst_aggr_type (context, args, complain,
6019 in_decl, /*entering_scope=*/1);
6021 /* Then, figure out what arguments are appropriate for the
6022 type we are trying to find. For example, given:
6024 template <class T> struct S;
6025 template <class T, class U> void f(T, U) { S<U> su; }
6027 and supposing that we are instantiating f<int, double>,
6028 then our ARGS will be {int, double}, but, when looking up
6029 S we only want {double}. */
6030 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6032 if (argvec == error_mark_node)
6033 return error_mark_node;
6035 r = lookup_template_class (t, argvec, in_decl, context,
6036 entering_scope, complain);
6038 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6041 /* This is not a template type, so there's nothing to do. */
6045 return tsubst (t, args, complain, in_decl);
6049 /* Substitute into the default argument ARG (a default argument for
6050 FN), which has the indicated TYPE. */
6053 tsubst_default_argument (tree fn, tree type, tree arg)
6055 tree saved_class_ptr = NULL_TREE;
6056 tree saved_class_ref = NULL_TREE;
6058 /* This default argument came from a template. Instantiate the
6059 default argument here, not in tsubst. In the case of
6068 we must be careful to do name lookup in the scope of S<T>,
6069 rather than in the current class. */
6070 push_access_scope (fn);
6071 /* The default argument expression should not be considered to be
6072 within the scope of FN. Since push_access_scope sets
6073 current_function_decl, we must explicitly clear it here. */
6074 current_function_decl = NULL_TREE;
6075 /* The "this" pointer is not valid in a default argument. */
6078 saved_class_ptr = current_class_ptr;
6079 cp_function_chain->x_current_class_ptr = NULL_TREE;
6080 saved_class_ref = current_class_ref;
6081 cp_function_chain->x_current_class_ref = NULL_TREE;
6084 push_deferring_access_checks(dk_no_deferred);
6085 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6086 tf_error | tf_warning, NULL_TREE);
6087 pop_deferring_access_checks();
6089 /* Restore the "this" pointer. */
6092 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6093 cp_function_chain->x_current_class_ref = saved_class_ref;
6096 pop_access_scope (fn);
6098 /* Make sure the default argument is reasonable. */
6099 arg = check_default_argument (type, arg);
6104 /* Substitute into all the default arguments for FN. */
6107 tsubst_default_arguments (tree fn)
6112 tmpl_args = DECL_TI_ARGS (fn);
6114 /* If this function is not yet instantiated, we certainly don't need
6115 its default arguments. */
6116 if (uses_template_parms (tmpl_args))
6119 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6121 arg = TREE_CHAIN (arg))
6122 if (TREE_PURPOSE (arg))
6123 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6125 TREE_PURPOSE (arg));
6128 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
6129 (already computed) substitution of ARGS into TREE_TYPE (T), if
6130 appropriate. Return the result of the substitution. Issue error
6131 and warning messages under control of COMPLAIN. */
6134 tsubst_decl (tree t, tree args, tree type, tsubst_flags_t complain)
6136 location_t saved_loc;
6140 /* Set the filename and linenumber to improve error-reporting. */
6141 saved_loc = input_location;
6142 input_location = DECL_SOURCE_LOCATION (t);
6144 switch (TREE_CODE (t))
6148 /* We can get here when processing a member template function
6149 of a template class. */
6150 tree decl = DECL_TEMPLATE_RESULT (t);
6152 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
6154 if (!is_template_template_parm)
6156 /* We might already have an instance of this template.
6157 The ARGS are for the surrounding class type, so the
6158 full args contain the tsubst'd args for the context,
6159 plus the innermost args from the template decl. */
6160 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6161 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6162 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6165 full_args = tsubst_template_args (tmpl_args, args,
6168 /* tsubst_template_args doesn't copy the vector if
6169 nothing changed. But, *something* should have
6171 gcc_assert (full_args != tmpl_args);
6173 spec = retrieve_specialization (t, full_args,
6174 /*class_specializations_p=*/true);
6175 if (spec != NULL_TREE)
6182 /* Make a new template decl. It will be similar to the
6183 original, but will record the current template arguments.
6184 We also create a new function declaration, which is just
6185 like the old one, but points to this new template, rather
6186 than the old one. */
6188 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6189 TREE_CHAIN (r) = NULL_TREE;
6191 if (is_template_template_parm)
6193 tree new_decl = tsubst (decl, args, complain, in_decl);
6194 DECL_TEMPLATE_RESULT (r) = new_decl;
6195 TREE_TYPE (r) = TREE_TYPE (new_decl);
6200 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6202 /*entering_scope=*/1);
6203 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6205 if (TREE_CODE (decl) == TYPE_DECL)
6207 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6208 if (new_type == error_mark_node)
6209 return error_mark_node;
6211 TREE_TYPE (r) = new_type;
6212 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6213 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6214 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6218 tree new_decl = tsubst (decl, args, complain, in_decl);
6219 if (new_decl == error_mark_node)
6220 return error_mark_node;
6222 DECL_TEMPLATE_RESULT (r) = new_decl;
6223 DECL_TI_TEMPLATE (new_decl) = r;
6224 TREE_TYPE (r) = TREE_TYPE (new_decl);
6225 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6228 SET_DECL_IMPLICIT_INSTANTIATION (r);
6229 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6230 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6232 /* The template parameters for this new template are all the
6233 template parameters for the old template, except the
6234 outermost level of parameters. */
6235 DECL_TEMPLATE_PARMS (r)
6236 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6239 if (PRIMARY_TEMPLATE_P (t))
6240 DECL_PRIMARY_TEMPLATE (r) = r;
6242 if (TREE_CODE (decl) != TYPE_DECL)
6243 /* Record this non-type partial instantiation. */
6244 register_specialization (r, t,
6245 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6252 tree argvec = NULL_TREE;
6259 /* Nobody should be tsubst'ing into non-template functions. */
6260 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6262 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6267 /* If T is not dependent, just return it. We have to
6268 increment PROCESSING_TEMPLATE_DECL because
6269 value_dependent_expression_p assumes that nothing is
6270 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6271 ++processing_template_decl;
6272 dependent_p = value_dependent_expression_p (t);
6273 --processing_template_decl;
6277 /* Calculate the most general template of which R is a
6278 specialization, and the complete set of arguments used to
6280 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6281 argvec = tsubst_template_args (DECL_TI_ARGS
6282 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6283 args, complain, in_decl);
6285 /* Check to see if we already have this specialization. */
6286 spec = retrieve_specialization (gen_tmpl, argvec,
6287 /*class_specializations_p=*/false);
6295 /* We can see more levels of arguments than parameters if
6296 there was a specialization of a member template, like
6299 template <class T> struct S { template <class U> void f(); }
6300 template <> template <class U> void S<int>::f(U);
6302 Here, we'll be substituting into the specialization,
6303 because that's where we can find the code we actually
6304 want to generate, but we'll have enough arguments for
6305 the most general template.
6307 We also deal with the peculiar case:
6309 template <class T> struct S {
6310 template <class U> friend void f();
6312 template <class U> void f() {}
6314 template void f<double>();
6316 Here, the ARGS for the instantiation of will be {int,
6317 double}. But, we only need as many ARGS as there are
6318 levels of template parameters in CODE_PATTERN. We are
6319 careful not to get fooled into reducing the ARGS in
6322 template <class T> struct S { template <class U> void f(U); }
6323 template <class T> template <> void S<T>::f(int) {}
6325 which we can spot because the pattern will be a
6326 specialization in this case. */
6327 args_depth = TMPL_ARGS_DEPTH (args);
6329 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6330 if (args_depth > parms_depth
6331 && !DECL_TEMPLATE_SPECIALIZATION (t))
6332 args = get_innermost_template_args (args, parms_depth);
6336 /* This special case arises when we have something like this:
6338 template <class T> struct S {
6339 friend void f<int>(int, double);
6342 Here, the DECL_TI_TEMPLATE for the friend declaration
6343 will be an IDENTIFIER_NODE. We are being called from
6344 tsubst_friend_function, and we want only to create a
6345 new decl (R) with appropriate types so that we can call
6346 determine_specialization. */
6347 gen_tmpl = NULL_TREE;
6350 if (DECL_CLASS_SCOPE_P (t))
6352 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6356 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6357 complain, t, /*entering_scope=*/1);
6362 ctx = DECL_CONTEXT (t);
6364 type = tsubst (type, args, complain, in_decl);
6365 if (type == error_mark_node)
6366 return error_mark_node;
6368 /* We do NOT check for matching decls pushed separately at this
6369 point, as they may not represent instantiations of this
6370 template, and in any case are considered separate under the
6373 DECL_USE_TEMPLATE (r) = 0;
6374 TREE_TYPE (r) = type;
6375 /* Clear out the mangled name and RTL for the instantiation. */
6376 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6377 SET_DECL_RTL (r, NULL_RTX);
6378 DECL_INITIAL (r) = NULL_TREE;
6379 DECL_CONTEXT (r) = ctx;
6381 if (member && DECL_CONV_FN_P (r))
6382 /* Type-conversion operator. Reconstruct the name, in
6383 case it's the name of one of the template's parameters. */
6384 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6386 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6388 DECL_RESULT (r) = NULL_TREE;
6390 TREE_STATIC (r) = 0;
6391 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6392 DECL_EXTERNAL (r) = 1;
6393 /* If this is an instantiation of a function with internal
6394 linkage, we already know what object file linkage will be
6395 assigned to the instantiation. */
6396 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6397 DECL_DEFER_OUTPUT (r) = 0;
6398 TREE_CHAIN (r) = NULL_TREE;
6399 DECL_PENDING_INLINE_INFO (r) = 0;
6400 DECL_PENDING_INLINE_P (r) = 0;
6401 DECL_SAVED_TREE (r) = NULL_TREE;
6403 if (DECL_CLONED_FUNCTION (r))
6405 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6407 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6408 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6411 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6412 this in the special friend case mentioned above where
6413 GEN_TMPL is NULL. */
6416 DECL_TEMPLATE_INFO (r)
6417 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6418 SET_DECL_IMPLICIT_INSTANTIATION (r);
6419 register_specialization (r, gen_tmpl, argvec);
6421 /* We're not supposed to instantiate default arguments
6422 until they are called, for a template. But, for a
6425 template <class T> void f ()
6426 { extern void g(int i = T()); }
6428 we should do the substitution when the template is
6429 instantiated. We handle the member function case in
6430 instantiate_class_template since the default arguments
6431 might refer to other members of the class. */
6433 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6434 && !uses_template_parms (argvec))
6435 tsubst_default_arguments (r);
6438 /* Copy the list of befriending classes. */
6439 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6441 friends = &TREE_CHAIN (*friends))
6443 *friends = copy_node (*friends);
6444 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6449 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6451 maybe_retrofit_in_chrg (r);
6452 if (DECL_CONSTRUCTOR_P (r))
6453 grok_ctor_properties (ctx, r);
6454 /* If this is an instantiation of a member template, clone it.
6455 If it isn't, that'll be handled by
6456 clone_constructors_and_destructors. */
6457 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6458 clone_function_decl (r, /*update_method_vec_p=*/0);
6460 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6461 grok_op_properties (r, DECL_FRIEND_P (r),
6462 (complain & tf_error) != 0);
6464 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6465 SET_DECL_FRIEND_CONTEXT (r,
6466 tsubst (DECL_FRIEND_CONTEXT (t),
6467 args, complain, in_decl));
6474 if (DECL_TEMPLATE_PARM_P (t))
6475 SET_DECL_TEMPLATE_PARM_P (r);
6477 TREE_TYPE (r) = type;
6478 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6480 if (DECL_INITIAL (r))
6482 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6483 DECL_INITIAL (r) = TREE_TYPE (r);
6485 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6489 DECL_CONTEXT (r) = NULL_TREE;
6491 if (!DECL_TEMPLATE_PARM_P (r))
6492 DECL_ARG_TYPE (r) = type_passed_as (type);
6494 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6495 complain, TREE_CHAIN (t));
6502 TREE_TYPE (r) = type;
6503 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6505 /* We don't have to set DECL_CONTEXT here; it is set by
6506 finish_member_declaration. */
6507 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6509 TREE_CHAIN (r) = NULL_TREE;
6510 if (VOID_TYPE_P (type))
6511 cp_error_at ("instantiation of %qD as type %qT", r, type);
6518 /* It is not a dependent using decl any more. */
6519 TREE_TYPE (r) = void_type_node;
6521 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6523 = tsubst_copy (DECL_NAME (t), args, complain, in_decl);
6524 TREE_CHAIN (r) = NULL_TREE;
6529 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6530 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6532 /* If this is the canonical decl, we don't have to mess with
6533 instantiations, and often we can't (for typename, template
6534 type parms and such). Note that TYPE_NAME is not correct for
6535 the above test if we've copied the type for a typedef. */
6536 r = TYPE_NAME (type);
6544 tree argvec = NULL_TREE;
6545 tree gen_tmpl = NULL_TREE;
6547 tree tmpl = NULL_TREE;
6551 /* Assume this is a non-local variable. */
6554 if (TYPE_P (CP_DECL_CONTEXT (t)))
6555 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6557 in_decl, /*entering_scope=*/1);
6558 else if (DECL_NAMESPACE_SCOPE_P (t))
6559 ctx = DECL_CONTEXT (t);
6562 /* Subsequent calls to pushdecl will fill this in. */
6567 /* Check to see if we already have this specialization. */
6570 tmpl = DECL_TI_TEMPLATE (t);
6571 gen_tmpl = most_general_template (tmpl);
6572 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6573 spec = retrieve_specialization (gen_tmpl, argvec,
6574 /*class_specializations_p=*/false);
6577 spec = retrieve_local_specialization (t);
6586 if (TREE_CODE (r) == VAR_DECL)
6588 type = complete_type (type);
6589 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6590 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6591 type = check_var_type (DECL_NAME (r), type);
6593 else if (DECL_SELF_REFERENCE_P (t))
6594 SET_DECL_SELF_REFERENCE_P (r);
6595 TREE_TYPE (r) = type;
6596 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6597 DECL_CONTEXT (r) = ctx;
6598 /* Clear out the mangled name and RTL for the instantiation. */
6599 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6600 SET_DECL_RTL (r, NULL_RTX);
6602 /* Don't try to expand the initializer until someone tries to use
6603 this variable; otherwise we run into circular dependencies. */
6604 DECL_INITIAL (r) = NULL_TREE;
6605 SET_DECL_RTL (r, NULL_RTX);
6606 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6608 /* Even if the original location is out of scope, the newly
6609 substituted one is not. */
6610 if (TREE_CODE (r) == VAR_DECL)
6612 DECL_DEAD_FOR_LOCAL (r) = 0;
6613 DECL_INITIALIZED_P (r) = 0;
6618 /* A static data member declaration is always marked
6619 external when it is declared in-class, even if an
6620 initializer is present. We mimic the non-template
6622 DECL_EXTERNAL (r) = 1;
6624 register_specialization (r, gen_tmpl, argvec);
6625 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6626 SET_DECL_IMPLICIT_INSTANTIATION (r);
6629 register_local_specialization (r, t);
6631 TREE_CHAIN (r) = NULL_TREE;
6640 /* Restore the file and line information. */
6641 input_location = saved_loc;
6646 /* Substitute into the ARG_TYPES of a function type. */
6649 tsubst_arg_types (tree arg_types,
6651 tsubst_flags_t complain,
6654 tree remaining_arg_types;
6657 if (!arg_types || arg_types == void_list_node)
6660 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6661 args, complain, in_decl);
6662 if (remaining_arg_types == error_mark_node)
6663 return error_mark_node;
6665 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6666 if (type == error_mark_node)
6667 return error_mark_node;
6668 if (VOID_TYPE_P (type))
6670 if (complain & tf_error)
6672 error ("invalid parameter type %qT", type);
6674 cp_error_at ("in declaration %qD", in_decl);
6676 return error_mark_node;
6679 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6680 top-level qualifiers as required. */
6681 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6683 /* Note that we do not substitute into default arguments here. The
6684 standard mandates that they be instantiated only when needed,
6685 which is done in build_over_call. */
6686 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6687 remaining_arg_types);
6691 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6692 *not* handle the exception-specification for FNTYPE, because the
6693 initial substitution of explicitly provided template parameters
6694 during argument deduction forbids substitution into the
6695 exception-specification:
6699 All references in the function type of the function template to the
6700 corresponding template parameters are replaced by the specified tem-
6701 plate argument values. If a substitution in a template parameter or
6702 in the function type of the function template results in an invalid
6703 type, type deduction fails. [Note: The equivalent substitution in
6704 exception specifications is done only when the function is instanti-
6705 ated, at which point a program is ill-formed if the substitution
6706 results in an invalid type.] */
6709 tsubst_function_type (tree t,
6711 tsubst_flags_t complain,
6718 /* The TYPE_CONTEXT is not used for function/method types. */
6719 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6721 /* Substitute the return type. */
6722 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6723 if (return_type == error_mark_node)
6724 return error_mark_node;
6726 /* Substitute the argument types. */
6727 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6729 if (arg_types == error_mark_node)
6730 return error_mark_node;
6732 /* Construct a new type node and return it. */
6733 if (TREE_CODE (t) == FUNCTION_TYPE)
6734 fntype = build_function_type (return_type, arg_types);
6737 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6738 if (! IS_AGGR_TYPE (r))
6742 Type deduction may fail for any of the following
6745 -- Attempting to create "pointer to member of T" when T
6746 is not a class type. */
6747 if (complain & tf_error)
6748 error ("creating pointer to member function of non-class type %qT",
6750 return error_mark_node;
6753 fntype = build_method_type_directly (r, return_type,
6754 TREE_CHAIN (arg_types));
6756 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6757 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6762 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6763 ARGS into that specification, and return the substituted
6764 specification. If there is no specification, return NULL_TREE. */
6767 tsubst_exception_specification (tree fntype,
6769 tsubst_flags_t complain,
6775 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6776 new_specs = NULL_TREE;
6779 if (! TREE_VALUE (specs))
6785 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6786 if (spec == error_mark_node)
6788 new_specs = add_exception_specifier (new_specs, spec, complain);
6789 specs = TREE_CHAIN (specs);
6795 /* Substitute into the PARMS of a call-declarator. */
6798 tsubst_call_declarator_parms (tree parms,
6800 tsubst_flags_t complain,
6807 if (!parms || parms == void_list_node)
6810 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6811 args, complain, in_decl);
6813 /* Figure out the type of this parameter. */
6814 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6816 /* Figure out the default argument as well. Note that we use
6817 tsubst_expr since the default argument is really an expression. */
6818 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6820 /* Chain this parameter on to the front of those we have already
6821 processed. We don't use hash_tree_cons because that function
6822 doesn't check TREE_PARMLIST. */
6823 new_parms = tree_cons (defarg, type, new_parms);
6828 /* Take the tree structure T and replace template parameters used
6829 therein with the argument vector ARGS. IN_DECL is an associated
6830 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6831 Issue error and warning messages under control of COMPLAIN. Note
6832 that we must be relatively non-tolerant of extensions here, in
6833 order to preserve conformance; if we allow substitutions that
6834 should not be allowed, we may allow argument deductions that should
6835 not succeed, and therefore report ambiguous overload situations
6836 where there are none. In theory, we could allow the substitution,
6837 but indicate that it should have failed, and allow our caller to
6838 make sure that the right thing happens, but we don't try to do this
6841 This function is used for dealing with types, decls and the like;
6842 for expressions, use tsubst_expr or tsubst_copy. */
6845 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6849 if (t == NULL_TREE || t == error_mark_node
6850 || t == integer_type_node
6851 || t == void_type_node
6852 || t == char_type_node
6853 || t == unknown_type_node
6854 || TREE_CODE (t) == NAMESPACE_DECL)
6857 if (TREE_CODE (t) == IDENTIFIER_NODE)
6858 type = IDENTIFIER_TYPE_VALUE (t);
6860 type = TREE_TYPE (t);
6862 gcc_assert (type != unknown_type_node);
6864 if (type && TREE_CODE (t) != FUNCTION_DECL
6865 && TREE_CODE (t) != TYPENAME_TYPE
6866 && TREE_CODE (t) != TEMPLATE_DECL
6867 && TREE_CODE (t) != IDENTIFIER_NODE
6868 && TREE_CODE (t) != FUNCTION_TYPE
6869 && TREE_CODE (t) != METHOD_TYPE)
6870 type = tsubst (type, args, complain, in_decl);
6871 if (type == error_mark_node)
6872 return error_mark_node;
6875 return tsubst_decl (t, args, type, complain);
6877 switch (TREE_CODE (t))
6882 return tsubst_aggr_type (t, args, complain, in_decl,
6883 /*entering_scope=*/0);
6886 case IDENTIFIER_NODE:
6898 if (t == integer_type_node)
6901 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6902 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6906 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6908 /* The array dimension behaves like a non-type template arg,
6909 in that we want to fold it as much as possible. */
6910 max = tsubst_template_arg (omax, args, complain, in_decl);
6911 if (!processing_template_decl)
6912 max = decl_constant_value (max);
6914 if (integer_zerop (omax))
6916 /* Still allow an explicit array of size zero. */
6918 pedwarn ("creating array with size zero");
6920 else if (integer_zerop (max)
6921 || (TREE_CODE (max) == INTEGER_CST
6922 && INT_CST_LT (max, integer_zero_node)))
6926 Type deduction may fail for any of the following
6929 Attempting to create an array with a size that is
6930 zero or negative. */
6931 if (complain & tf_error)
6932 error ("creating array with size zero (%qE)", max);
6934 return error_mark_node;
6937 return compute_array_index_type (NULL_TREE, max);
6940 case TEMPLATE_TYPE_PARM:
6941 case TEMPLATE_TEMPLATE_PARM:
6942 case BOUND_TEMPLATE_TEMPLATE_PARM:
6943 case TEMPLATE_PARM_INDEX:
6948 tree arg = NULL_TREE;
6952 gcc_assert (TREE_VEC_LENGTH (args) > 0);
6953 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6954 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6955 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6957 idx = TEMPLATE_TYPE_IDX (t);
6958 level = TEMPLATE_TYPE_LEVEL (t);
6962 idx = TEMPLATE_PARM_IDX (t);
6963 level = TEMPLATE_PARM_LEVEL (t);
6966 levels = TMPL_ARGS_DEPTH (args);
6967 if (level <= levels)
6968 arg = TMPL_ARG (args, level, idx);
6970 if (arg == error_mark_node)
6971 return error_mark_node;
6972 else if (arg != NULL_TREE)
6974 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6976 gcc_assert (TYPE_P (arg));
6977 return cp_build_qualified_type_real
6978 (arg, cp_type_quals (arg) | cp_type_quals (t),
6979 complain | tf_ignore_bad_quals);
6981 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6983 /* We are processing a type constructed from a
6984 template template parameter. */
6985 tree argvec = tsubst (TYPE_TI_ARGS (t),
6986 args, complain, in_decl);
6987 if (argvec == error_mark_node)
6988 return error_mark_node;
6990 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
6991 are resolving nested-types in the signature of a
6992 member function templates. Otherwise ARG is a
6993 TEMPLATE_DECL and is the real template to be
6995 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
6996 arg = TYPE_NAME (arg);
6998 r = lookup_template_class (arg,
7001 /*entering_scope=*/0,
7003 return cp_build_qualified_type_real
7004 (r, TYPE_QUALS (t), complain);
7007 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7012 /* This can happen during the attempted tsubst'ing in
7013 unify. This means that we don't yet have any information
7014 about the template parameter in question. */
7017 /* If we get here, we must have been looking at a parm for a
7018 more deeply nested template. Make a new version of this
7019 template parameter, but with a lower level. */
7020 switch (TREE_CODE (t))
7022 case TEMPLATE_TYPE_PARM:
7023 case TEMPLATE_TEMPLATE_PARM:
7024 case BOUND_TEMPLATE_TEMPLATE_PARM:
7025 if (cp_type_quals (t))
7027 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7028 r = cp_build_qualified_type_real
7029 (r, cp_type_quals (t),
7030 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7031 ? tf_ignore_bad_quals : 0));
7036 TEMPLATE_TYPE_PARM_INDEX (r)
7037 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7039 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7040 TYPE_MAIN_VARIANT (r) = r;
7041 TYPE_POINTER_TO (r) = NULL_TREE;
7042 TYPE_REFERENCE_TO (r) = NULL_TREE;
7044 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7046 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7048 if (argvec == error_mark_node)
7049 return error_mark_node;
7051 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7052 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7057 case TEMPLATE_PARM_INDEX:
7058 r = reduce_template_parm_level (t, type, levels);
7070 tree purpose, value, chain;
7072 if (t == void_list_node)
7075 purpose = TREE_PURPOSE (t);
7078 purpose = tsubst (purpose, args, complain, in_decl);
7079 if (purpose == error_mark_node)
7080 return error_mark_node;
7082 value = TREE_VALUE (t);
7085 value = tsubst (value, args, complain, in_decl);
7086 if (value == error_mark_node)
7087 return error_mark_node;
7089 chain = TREE_CHAIN (t);
7090 if (chain && chain != void_type_node)
7092 chain = tsubst (chain, args, complain, in_decl);
7093 if (chain == error_mark_node)
7094 return error_mark_node;
7096 if (purpose == TREE_PURPOSE (t)
7097 && value == TREE_VALUE (t)
7098 && chain == TREE_CHAIN (t))
7100 return hash_tree_cons (purpose, value, chain);
7104 /* We should never be tsubsting a binfo. */
7108 /* A vector of template arguments. */
7110 return tsubst_template_args (t, args, complain, in_decl);
7113 case REFERENCE_TYPE:
7115 enum tree_code code;
7117 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7120 code = TREE_CODE (t);
7125 Type deduction may fail for any of the following
7128 -- Attempting to create a pointer to reference type.
7129 -- Attempting to create a reference to a reference type or
7130 a reference to void. */
7131 if (TREE_CODE (type) == REFERENCE_TYPE
7132 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7134 static location_t last_loc;
7136 /* We keep track of the last time we issued this error
7137 message to avoid spewing a ton of messages during a
7138 single bad template instantiation. */
7139 if (complain & tf_error
7140 #ifdef USE_MAPPED_LOCATION
7141 && last_loc != input_location
7143 && (last_loc.line != input_line
7144 || last_loc.file != input_filename)
7148 if (TREE_CODE (type) == VOID_TYPE)
7149 error ("forming reference to void");
7151 error ("forming %s to reference type %qT",
7152 (code == POINTER_TYPE) ? "pointer" : "reference",
7154 last_loc = input_location;
7157 return error_mark_node;
7159 else if (code == POINTER_TYPE)
7161 r = build_pointer_type (type);
7162 if (TREE_CODE (type) == METHOD_TYPE)
7163 r = build_ptrmemfunc_type (r);
7166 r = build_reference_type (type);
7167 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7169 if (r != error_mark_node)
7170 /* Will this ever be needed for TYPE_..._TO values? */
7177 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7178 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7182 Type deduction may fail for any of the following
7185 -- Attempting to create "pointer to member of T" when T
7186 is not a class type. */
7187 if (complain & tf_error)
7188 error ("creating pointer to member of non-class type %qT", r);
7189 return error_mark_node;
7191 if (TREE_CODE (type) == REFERENCE_TYPE)
7193 if (complain & tf_error)
7194 error ("creating pointer to member reference type %qT", type);
7196 return error_mark_node;
7198 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7199 if (TREE_CODE (type) == FUNCTION_TYPE)
7201 /* This is really a method type. The cv qualifiers of the
7202 this pointer should _not_ be determined by the cv
7203 qualifiers of the class type. They should be held
7204 somewhere in the FUNCTION_TYPE, but we don't do that at
7205 the moment. Consider
7206 typedef void (Func) () const;
7208 template <typename T1> void Foo (Func T1::*);
7213 method_type = build_method_type_directly (TYPE_MAIN_VARIANT (r),
7215 TYPE_ARG_TYPES (type));
7216 return build_ptrmemfunc_type (build_pointer_type (method_type));
7219 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7228 fntype = tsubst_function_type (t, args, complain, in_decl);
7229 if (fntype == error_mark_node)
7230 return error_mark_node;
7232 /* Substitute the exception specification. */
7233 specs = tsubst_exception_specification (t, args, complain,
7236 fntype = build_exception_variant (fntype, specs);
7241 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7242 if (domain == error_mark_node)
7243 return error_mark_node;
7245 /* As an optimization, we avoid regenerating the array type if
7246 it will obviously be the same as T. */
7247 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7250 /* These checks should match the ones in grokdeclarator.
7254 The deduction may fail for any of the following reasons:
7256 -- Attempting to create an array with an element type that
7257 is void, a function type, or a reference type, or [DR337]
7258 an abstract class type. */
7259 if (TREE_CODE (type) == VOID_TYPE
7260 || TREE_CODE (type) == FUNCTION_TYPE
7261 || TREE_CODE (type) == REFERENCE_TYPE)
7263 if (complain & tf_error)
7264 error ("creating array of %qT", type);
7265 return error_mark_node;
7267 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7269 if (complain & tf_error)
7270 error ("creating array of %qT, which is an abstract class type",
7272 return error_mark_node;
7275 r = build_cplus_array_type (type, domain);
7282 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7283 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7285 if (e1 == error_mark_node || e2 == error_mark_node)
7286 return error_mark_node;
7288 return fold (build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2));
7294 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7295 if (e == error_mark_node)
7296 return error_mark_node;
7298 return fold (build1 (TREE_CODE (t), TREE_TYPE (t), e));
7303 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7304 in_decl, /*entering_scope=*/1);
7305 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7308 if (ctx == error_mark_node || f == error_mark_node)
7309 return error_mark_node;
7311 if (!IS_AGGR_TYPE (ctx))
7313 if (complain & tf_error)
7314 error ("%qT is not a class, struct, or union type", ctx);
7315 return error_mark_node;
7317 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7319 /* Normally, make_typename_type does not require that the CTX
7320 have complete type in order to allow things like:
7322 template <class T> struct S { typename S<T>::X Y; };
7324 But, such constructs have already been resolved by this
7325 point, so here CTX really should have complete type, unless
7326 it's a partial instantiation. */
7327 ctx = complete_type (ctx);
7328 if (!COMPLETE_TYPE_P (ctx))
7330 if (complain & tf_error)
7331 cxx_incomplete_type_error (NULL_TREE, ctx);
7332 return error_mark_node;
7336 f = make_typename_type (ctx, f,
7337 (complain & tf_error) | tf_keep_type_decl);
7338 if (f == error_mark_node)
7340 if (TREE_CODE (f) == TYPE_DECL)
7342 complain |= tf_ignore_bad_quals;
7346 return cp_build_qualified_type_real
7347 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7350 case UNBOUND_CLASS_TEMPLATE:
7352 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7353 in_decl, /*entering_scope=*/1);
7354 tree name = TYPE_IDENTIFIER (t);
7355 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7357 if (ctx == error_mark_node || name == error_mark_node)
7358 return error_mark_node;
7361 parm_list = tsubst_template_parms (parm_list, args, complain);
7362 return make_unbound_class_template (ctx, name, parm_list, complain);
7372 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7373 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7374 if (e1 == error_mark_node || e2 == error_mark_node)
7375 return error_mark_node;
7377 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7382 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7383 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7384 if (e1 == error_mark_node || e2 == error_mark_node)
7385 return error_mark_node;
7387 return build_nt (TREE_CODE (t), e1, e2);
7394 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7395 complain, in_decl));
7396 return cp_build_qualified_type_real (type,
7398 | cp_type_quals (type),
7403 sorry ("use of `%s' in template",
7404 tree_code_name [(int) TREE_CODE (t)]);
7405 return error_mark_node;
7409 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7410 type of the expression on the left-hand side of the "." or "->"
7414 tsubst_baselink (tree baselink, tree object_type,
7415 tree args, tsubst_flags_t complain, tree in_decl)
7418 tree qualifying_scope;
7420 tree template_args = 0;
7421 bool template_id_p = false;
7423 /* A baselink indicates a function from a base class. The
7424 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7425 non-dependent types; otherwise, the lookup could not have
7426 succeeded. However, they may indicate bases of the template
7427 class, rather than the instantiated class.
7429 In addition, lookups that were not ambiguous before may be
7430 ambiguous now. Therefore, we perform the lookup again. */
7431 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7432 fns = BASELINK_FUNCTIONS (baselink);
7433 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7435 template_id_p = true;
7436 template_args = TREE_OPERAND (fns, 1);
7437 fns = TREE_OPERAND (fns, 0);
7439 template_args = tsubst_template_args (template_args, args,
7442 name = DECL_NAME (get_first_fn (fns));
7443 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7445 /* If lookup found a single function, mark it as used at this
7446 point. (If it lookup found multiple functions the one selected
7447 later by overload resolution will be marked as used at that
7449 if (BASELINK_P (baselink))
7450 fns = BASELINK_FUNCTIONS (baselink);
7451 if (!template_id_p && !really_overloaded_fn (fns))
7452 mark_used (OVL_CURRENT (fns));
7454 /* Add back the template arguments, if present. */
7455 if (BASELINK_P (baselink) && template_id_p)
7456 BASELINK_FUNCTIONS (baselink)
7457 = build_nt (TEMPLATE_ID_EXPR,
7458 BASELINK_FUNCTIONS (baselink),
7462 object_type = current_class_type;
7463 return adjust_result_of_qualified_name_lookup (baselink,
7468 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7469 true if the qualified-id will be a postfix-expression in-and-of
7470 itself; false if more of the postfix-expression follows the
7471 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7475 tsubst_qualified_id (tree qualified_id, tree args,
7476 tsubst_flags_t complain, tree in_decl,
7477 bool done, bool address_p)
7485 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7487 /* Figure out what name to look up. */
7488 name = TREE_OPERAND (qualified_id, 1);
7489 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7492 template_args = TREE_OPERAND (name, 1);
7494 template_args = tsubst_template_args (template_args, args,
7496 name = TREE_OPERAND (name, 0);
7500 is_template = false;
7501 template_args = NULL_TREE;
7504 /* Substitute into the qualifying scope. When there are no ARGS, we
7505 are just trying to simplify a non-dependent expression. In that
7506 case the qualifying scope may be dependent, and, in any case,
7507 substituting will not help. */
7508 scope = TREE_OPERAND (qualified_id, 0);
7511 scope = tsubst (scope, args, complain, in_decl);
7512 expr = tsubst_copy (name, args, complain, in_decl);
7517 if (dependent_type_p (scope))
7518 return build_nt (SCOPE_REF, scope, expr);
7520 if (!BASELINK_P (name) && !DECL_P (expr))
7522 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7523 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7524 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7526 if (complain & tf_error)
7528 error ("dependent-name %qE is parsed as a non-type, but "
7529 "instantiation yields a type", qualified_id);
7530 inform ("say %<typename %E%> if a type is meant", qualified_id);
7532 return error_mark_node;
7538 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7540 /* Remember that there was a reference to this entity. */
7544 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7546 if (complain & tf_error)
7547 qualified_name_lookup_error (scope,
7548 TREE_OPERAND (qualified_id, 1),
7550 return error_mark_node;
7554 expr = lookup_template_function (expr, template_args);
7556 if (expr == error_mark_node && complain & tf_error)
7557 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7559 else if (TYPE_P (scope))
7561 expr = (adjust_result_of_qualified_name_lookup
7562 (expr, scope, current_class_type));
7563 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7569 /* Like tsubst, but deals with expressions. This function just replaces
7570 template parms; to finish processing the resultant expression, use
7574 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7576 enum tree_code code;
7579 if (t == NULL_TREE || t == error_mark_node)
7582 code = TREE_CODE (t);
7587 r = retrieve_local_specialization (t);
7588 gcc_assert (r != NULL);
7597 if (DECL_TEMPLATE_PARM_P (t))
7598 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7599 /* There is no need to substitute into namespace-scope
7601 if (DECL_NAMESPACE_SCOPE_P (t))
7603 /* If ARGS is NULL, then T is known to be non-dependent. */
7604 if (args == NULL_TREE)
7605 return decl_constant_value (t);
7607 /* Unfortunately, we cannot just call lookup_name here.
7610 template <int I> int f() {
7612 struct S { void g() { E e = a; } };
7615 When we instantiate f<7>::S::g(), say, lookup_name is not
7616 clever enough to find f<7>::a. */
7618 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7619 /*entering_scope=*/0);
7621 for (v = TYPE_VALUES (enum_type);
7624 if (TREE_PURPOSE (v) == DECL_NAME (t))
7625 return TREE_VALUE (v);
7627 /* We didn't find the name. That should never happen; if
7628 name-lookup found it during preliminary parsing, we
7629 should find it again here during instantiation. */
7635 if (DECL_CONTEXT (t))
7639 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7640 /*entering_scope=*/1);
7641 if (ctx != DECL_CONTEXT (t))
7642 return lookup_field (ctx, DECL_NAME (t), 0, false);
7649 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7650 || local_variable_p (t))
7651 t = tsubst (t, args, complain, in_decl);
7656 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7659 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7660 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7661 args, complain, in_decl);
7662 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7663 return tsubst (t, args, complain, in_decl);
7664 else if (DECL_CLASS_SCOPE_P (t)
7665 && uses_template_parms (DECL_CONTEXT (t)))
7667 /* Template template argument like the following example need
7670 template <template <class> class TT> struct C {};
7671 template <class T> struct D {
7672 template <class U> struct E {};
7677 We are processing the template argument `E' in #1 for
7678 the template instantiation #2. Originally, `E' is a
7679 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7680 have to substitute this with one having context `D<int>'. */
7682 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7683 return lookup_field (context, DECL_NAME(t), 0, false);
7686 /* Ordinary template template argument. */
7690 case REINTERPRET_CAST_EXPR:
7691 case CONST_CAST_EXPR:
7692 case STATIC_CAST_EXPR:
7693 case DYNAMIC_CAST_EXPR:
7696 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7697 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7701 case TRUTH_NOT_EXPR:
7704 case CONVERT_EXPR: /* Unary + */
7713 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7714 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7721 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7722 name = TREE_OPERAND (t, 1);
7723 if (TREE_CODE (name) == BIT_NOT_EXPR)
7725 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7727 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7729 else if (TREE_CODE (name) == SCOPE_REF
7730 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7732 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7734 name = TREE_OPERAND (name, 1);
7735 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7737 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7738 name = build_nt (SCOPE_REF, base, name);
7740 else if (TREE_CODE (name) == BASELINK)
7741 name = tsubst_baselink (name,
7742 non_reference (TREE_TYPE (object)),
7746 name = tsubst_copy (name, args, complain, in_decl);
7747 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7753 case TRUNC_DIV_EXPR:
7755 case FLOOR_DIV_EXPR:
7756 case ROUND_DIV_EXPR:
7757 case EXACT_DIV_EXPR:
7761 case TRUNC_MOD_EXPR:
7762 case FLOOR_MOD_EXPR:
7763 case TRUTH_ANDIF_EXPR:
7764 case TRUTH_ORIF_EXPR:
7765 case TRUTH_AND_EXPR:
7784 case PREDECREMENT_EXPR:
7785 case PREINCREMENT_EXPR:
7786 case POSTDECREMENT_EXPR:
7787 case POSTINCREMENT_EXPR:
7789 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7790 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7793 return build_nt (code,
7794 tsubst_copy (TREE_OPERAND (t, 0), args,
7796 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7802 case PSEUDO_DTOR_EXPR:
7805 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7806 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7807 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7808 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7815 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7816 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7817 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7818 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7825 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7826 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7827 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7828 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7832 case TEMPLATE_ID_EXPR:
7834 /* Substituted template arguments */
7835 tree fn = TREE_OPERAND (t, 0);
7836 tree targs = TREE_OPERAND (t, 1);
7838 fn = tsubst_copy (fn, args, complain, in_decl);
7840 targs = tsubst_template_args (targs, args, complain, in_decl);
7842 return lookup_template_function (fn, targs);
7847 tree purpose, value, chain;
7849 if (t == void_list_node)
7852 purpose = TREE_PURPOSE (t);
7854 purpose = tsubst_copy (purpose, args, complain, in_decl);
7855 value = TREE_VALUE (t);
7857 value = tsubst_copy (value, args, complain, in_decl);
7858 chain = TREE_CHAIN (t);
7859 if (chain && chain != void_type_node)
7860 chain = tsubst_copy (chain, args, complain, in_decl);
7861 if (purpose == TREE_PURPOSE (t)
7862 && value == TREE_VALUE (t)
7863 && chain == TREE_CHAIN (t))
7865 return tree_cons (purpose, value, chain);
7872 case TEMPLATE_TYPE_PARM:
7873 case TEMPLATE_TEMPLATE_PARM:
7874 case BOUND_TEMPLATE_TEMPLATE_PARM:
7875 case TEMPLATE_PARM_INDEX:
7877 case REFERENCE_TYPE:
7883 case UNBOUND_CLASS_TEMPLATE:
7886 return tsubst (t, args, complain, in_decl);
7888 case IDENTIFIER_NODE:
7889 if (IDENTIFIER_TYPENAME_P (t))
7891 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7892 return mangle_conv_op_name_for_type (new_type);
7899 r = build_constructor
7900 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7901 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7902 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7907 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7909 tsubst (TREE_TYPE (t), args, complain, in_decl));
7911 case CLEANUP_POINT_EXPR:
7912 /* We shouldn't have built any of these during initial template
7913 generation. Instead, they should be built during instantiation
7914 in response to the saved STMT_IS_FULL_EXPR_P setting. */
7922 /* Like tsubst_copy for expressions, etc. but also does semantic
7926 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7930 if (t == NULL_TREE || t == error_mark_node)
7933 if (EXPR_HAS_LOCATION (t))
7934 input_location = EXPR_LOCATION (t);
7935 if (STATEMENT_CODE_P (TREE_CODE (t)))
7936 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
7938 switch (TREE_CODE (t))
7940 case STATEMENT_LIST:
7942 tree_stmt_iterator i;
7943 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
7944 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
7948 case CTOR_INITIALIZER:
7949 finish_mem_initializers (tsubst_initializer_list
7950 (TREE_OPERAND (t, 0), args));
7954 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
7955 args, complain, in_decl));
7959 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
7960 if (EXPR_STMT_STMT_EXPR_RESULT (t))
7961 finish_stmt_expr_expr (tmp, cur_stmt_expr);
7963 finish_expr_stmt (tmp);
7967 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
7968 args, complain, in_decl));
7976 decl = DECL_EXPR_DECL (t);
7977 if (TREE_CODE (decl) == LABEL_DECL)
7978 finish_label_decl (DECL_NAME (decl));
7979 else if (TREE_CODE (decl) == USING_DECL)
7981 tree scope = DECL_INITIAL (decl);
7982 tree name = DECL_NAME (decl);
7985 scope = tsubst_expr (scope, args, complain, in_decl);
7986 decl = lookup_qualified_name (scope, name,
7987 /*is_type_p=*/false,
7988 /*complain=*/false);
7989 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
7990 qualified_name_lookup_error (scope, name, decl);
7992 do_local_using_decl (decl, scope, name);
7996 init = DECL_INITIAL (decl);
7997 decl = tsubst (decl, args, complain, in_decl);
7998 if (decl != error_mark_node)
8001 DECL_INITIAL (decl) = error_mark_node;
8002 /* By marking the declaration as instantiated, we avoid
8003 trying to instantiate it. Since instantiate_decl can't
8004 handle local variables, and since we've already done
8005 all that needs to be done, that's the right thing to
8007 if (TREE_CODE (decl) == VAR_DECL)
8008 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8009 if (TREE_CODE (decl) == VAR_DECL
8010 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8011 /* Anonymous aggregates are a special case. */
8012 finish_anon_union (decl);
8015 maybe_push_decl (decl);
8016 if (TREE_CODE (decl) == VAR_DECL
8017 && DECL_PRETTY_FUNCTION_P (decl))
8019 /* For __PRETTY_FUNCTION__ we have to adjust the
8021 const char *const name
8022 = cxx_printable_name (current_function_decl, 2);
8023 init = cp_fname_init (name, &TREE_TYPE (decl));
8026 init = tsubst_expr (init, args, complain, in_decl);
8027 cp_finish_decl (decl, init, NULL_TREE, 0);
8032 /* A DECL_EXPR can also be used as an expression, in the condition
8033 clause of an if/for/while construct. */
8038 stmt = begin_for_stmt ();
8039 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8040 finish_for_init_stmt (stmt);
8041 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8042 finish_for_cond (tmp, stmt);
8043 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8044 finish_for_expr (tmp, stmt);
8045 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8046 finish_for_stmt (stmt);
8050 stmt = begin_while_stmt ();
8051 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8052 finish_while_stmt_cond (tmp, stmt);
8053 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8054 finish_while_stmt (stmt);
8058 stmt = begin_do_stmt ();
8059 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8060 finish_do_body (stmt);
8061 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8062 finish_do_stmt (tmp, stmt);
8066 stmt = begin_if_stmt ();
8067 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8068 finish_if_stmt_cond (tmp, stmt);
8069 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8070 finish_then_clause (stmt);
8072 if (ELSE_CLAUSE (t))
8074 begin_else_clause (stmt);
8075 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8076 finish_else_clause (stmt);
8079 finish_if_stmt (stmt);
8083 if (BIND_EXPR_BODY_BLOCK (t))
8084 stmt = begin_function_body ();
8086 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8087 ? BCS_TRY_BLOCK : 0);
8089 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8091 if (BIND_EXPR_BODY_BLOCK (t))
8092 finish_function_body (stmt);
8094 finish_compound_stmt (stmt);
8098 finish_break_stmt ();
8102 finish_continue_stmt ();
8106 stmt = begin_switch_stmt ();
8107 tmp = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
8108 finish_switch_cond (tmp, stmt);
8109 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
8110 finish_switch_stmt (stmt);
8113 case CASE_LABEL_EXPR:
8114 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8115 tsubst_expr (CASE_HIGH (t), args, complain,
8120 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8124 tmp = GOTO_DESTINATION (t);
8125 if (TREE_CODE (tmp) != LABEL_DECL)
8126 /* Computed goto's must be tsubst'd into. On the other hand,
8127 non-computed gotos must not be; the identifier in question
8128 will have no binding. */
8129 tmp = tsubst_expr (tmp, args, complain, in_decl);
8131 tmp = DECL_NAME (tmp);
8132 finish_goto_stmt (tmp);
8136 tmp = finish_asm_stmt
8137 (ASM_VOLATILE_P (t),
8138 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8139 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8140 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8141 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8143 tree asm_expr = tmp;
8144 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8145 asm_expr = TREE_OPERAND (asm_expr, 0);
8146 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8153 stmt = begin_try_block ();
8154 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8155 finish_cleanup_try_block (stmt);
8156 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8162 if (FN_TRY_BLOCK_P (t))
8163 stmt = begin_function_try_block ();
8165 stmt = begin_try_block ();
8167 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8169 if (FN_TRY_BLOCK_P (t))
8170 finish_function_try_block (stmt);
8172 finish_try_block (stmt);
8174 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8175 if (FN_TRY_BLOCK_P (t))
8176 finish_function_handler_sequence (stmt);
8178 finish_handler_sequence (stmt);
8186 stmt = begin_handler ();
8187 if (HANDLER_PARMS (t))
8189 decl = HANDLER_PARMS (t);
8190 decl = tsubst (decl, args, complain, in_decl);
8191 /* Prevent instantiate_decl from trying to instantiate
8192 this variable. We've already done all that needs to be
8194 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8198 finish_handler_parms (decl, stmt);
8199 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8200 finish_handler (stmt);
8205 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8209 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8211 return tsubst_copy_and_build (t, args, complain, in_decl,
8212 /*function_p=*/false);
8218 /* T is a postfix-expression that is not being used in a function
8219 call. Return the substituted version of T. */
8222 tsubst_non_call_postfix_expression (tree t, tree args,
8223 tsubst_flags_t complain,
8226 if (TREE_CODE (t) == SCOPE_REF)
8227 t = tsubst_qualified_id (t, args, complain, in_decl,
8228 /*done=*/false, /*address_p=*/false);
8230 t = tsubst_copy_and_build (t, args, complain, in_decl,
8231 /*function_p=*/false);
8236 /* Like tsubst but deals with expressions and performs semantic
8237 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8240 tsubst_copy_and_build (tree t,
8242 tsubst_flags_t complain,
8246 #define RECUR(NODE) \
8247 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8251 if (t == NULL_TREE || t == error_mark_node)
8254 switch (TREE_CODE (t))
8259 case IDENTIFIER_NODE:
8263 tree qualifying_class;
8264 bool non_integral_constant_expression_p;
8265 const char *error_msg;
8267 if (IDENTIFIER_TYPENAME_P (t))
8269 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8270 t = mangle_conv_op_name_for_type (new_type);
8273 /* Look up the name. */
8274 decl = lookup_name (t, 0);
8276 /* By convention, expressions use ERROR_MARK_NODE to indicate
8277 failure, not NULL_TREE. */
8278 if (decl == NULL_TREE)
8279 decl = error_mark_node;
8281 decl = finish_id_expression (t, decl, NULL_TREE,
8284 /*integral_constant_expression_p=*/false,
8285 /*allow_non_integral_constant_expression_p=*/false,
8286 &non_integral_constant_expression_p,
8290 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8291 decl = unqualified_name_lookup_error (decl);
8295 case TEMPLATE_ID_EXPR:
8298 tree template = RECUR (TREE_OPERAND (t, 0));
8299 tree targs = TREE_OPERAND (t, 1);
8302 targs = tsubst_template_args (targs, args, complain, in_decl);
8304 if (TREE_CODE (template) == COMPONENT_REF)
8306 object = TREE_OPERAND (template, 0);
8307 template = TREE_OPERAND (template, 1);
8311 template = lookup_template_function (template, targs);
8314 return build3 (COMPONENT_REF, TREE_TYPE (template),
8315 object, template, NULL_TREE);
8321 return build_x_indirect_ref (RECUR (TREE_OPERAND (t, 0)), "unary *");
8325 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8326 RECUR (TREE_OPERAND (t, 0)));
8329 return build_functional_cast
8330 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8331 RECUR (TREE_OPERAND (t, 0)));
8333 case REINTERPRET_CAST_EXPR:
8334 return build_reinterpret_cast
8335 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8336 RECUR (TREE_OPERAND (t, 0)));
8338 case CONST_CAST_EXPR:
8339 return build_const_cast
8340 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8341 RECUR (TREE_OPERAND (t, 0)));
8343 case DYNAMIC_CAST_EXPR:
8344 return build_dynamic_cast
8345 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8346 RECUR (TREE_OPERAND (t, 0)));
8348 case STATIC_CAST_EXPR:
8349 return build_static_cast
8350 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8351 RECUR (TREE_OPERAND (t, 0)));
8353 case POSTDECREMENT_EXPR:
8354 case POSTINCREMENT_EXPR:
8355 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8356 args, complain, in_decl);
8357 return build_x_unary_op (TREE_CODE (t), op1);
8359 case PREDECREMENT_EXPR:
8360 case PREINCREMENT_EXPR:
8364 case TRUTH_NOT_EXPR:
8365 case CONVERT_EXPR: /* Unary + */
8368 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8371 op1 = TREE_OPERAND (t, 0);
8372 if (TREE_CODE (op1) == SCOPE_REF)
8373 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8374 /*done=*/true, /*address_p=*/true);
8376 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8378 if (TREE_CODE (op1) == LABEL_DECL)
8379 return finish_label_address_expr (DECL_NAME (op1));
8380 return build_x_unary_op (ADDR_EXPR, op1);
8385 case TRUNC_DIV_EXPR:
8387 case FLOOR_DIV_EXPR:
8388 case ROUND_DIV_EXPR:
8389 case EXACT_DIV_EXPR:
8393 case TRUNC_MOD_EXPR:
8394 case FLOOR_MOD_EXPR:
8395 case TRUTH_ANDIF_EXPR:
8396 case TRUTH_ORIF_EXPR:
8397 case TRUTH_AND_EXPR:
8413 return build_x_binary_op
8415 RECUR (TREE_OPERAND (t, 0)),
8416 RECUR (TREE_OPERAND (t, 1)),
8417 /*overloaded_p=*/NULL);
8420 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8421 /*address_p=*/false);
8424 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8427 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)),
8428 NULL_TREE, NULL_TREE);
8430 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8431 args, complain, in_decl);
8432 /* Remember that there was a reference to this entity. */
8435 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8439 op1 = TREE_OPERAND (t, 0);
8442 /* When there are no ARGS, we are trying to evaluate a
8443 non-dependent expression from the parser. Trying to do
8444 the substitutions may not work. */
8446 op1 = TREE_TYPE (op1);
8455 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8457 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8461 tree r = build_x_modify_expr
8462 (RECUR (TREE_OPERAND (t, 0)),
8463 TREE_CODE (TREE_OPERAND (t, 1)),
8464 RECUR (TREE_OPERAND (t, 2)));
8465 /* TREE_NO_WARNING must be set if either the expression was
8466 parenthesized or it uses an operator such as >>= rather
8467 than plain assignment. In the former case, it was already
8468 set and must be copied. In the latter case,
8469 build_x_modify_expr sets it and it must not be reset
8471 if (TREE_NO_WARNING (t))
8472 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8477 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8478 args, complain, in_decl);
8479 /* Remember that there was a reference to this entity. */
8482 return build_x_arrow (op1);
8486 (RECUR (TREE_OPERAND (t, 0)),
8487 RECUR (TREE_OPERAND (t, 1)),
8488 RECUR (TREE_OPERAND (t, 2)),
8489 RECUR (TREE_OPERAND (t, 3)),
8490 NEW_EXPR_USE_GLOBAL (t));
8493 return delete_sanity
8494 (RECUR (TREE_OPERAND (t, 0)),
8495 RECUR (TREE_OPERAND (t, 1)),
8496 DELETE_EXPR_USE_VEC (t),
8497 DELETE_EXPR_USE_GLOBAL (t));
8500 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8501 RECUR (TREE_OPERAND (t, 1)));
8510 function = TREE_OPERAND (t, 0);
8511 /* When we parsed the expression, we determined whether or
8512 not Koenig lookup should be performed. */
8513 koenig_p = KOENIG_LOOKUP_P (t);
8514 if (TREE_CODE (function) == SCOPE_REF)
8517 function = tsubst_qualified_id (function, args, complain, in_decl,
8519 /*address_p=*/false);
8523 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8524 && (TREE_CODE (TREE_OPERAND (function, 1))
8526 function = tsubst_copy_and_build (function, args, complain,
8529 if (BASELINK_P (function))
8533 call_args = RECUR (TREE_OPERAND (t, 1));
8535 /* We do not perform argument-dependent lookup if normal
8536 lookup finds a non-function, in accordance with the
8537 expected resolution of DR 218. */
8539 && (is_overloaded_fn (function)
8540 || TREE_CODE (function) == IDENTIFIER_NODE))
8541 function = perform_koenig_lookup (function, call_args);
8543 if (TREE_CODE (function) == IDENTIFIER_NODE)
8545 unqualified_name_lookup_error (function);
8546 return error_mark_node;
8549 /* Remember that there was a reference to this entity. */
8550 if (DECL_P (function))
8551 mark_used (function);
8553 function = convert_from_reference (function);
8555 if (TREE_CODE (function) == OFFSET_REF)
8556 return build_offset_ref_call_from_tree (function, call_args);
8557 if (TREE_CODE (function) == COMPONENT_REF)
8559 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8560 return finish_call_expr (function, call_args,
8561 /*disallow_virtual=*/false,
8562 /*koenig_p=*/false);
8564 return (build_new_method_call
8565 (TREE_OPERAND (function, 0),
8566 TREE_OPERAND (function, 1),
8567 call_args, NULL_TREE,
8568 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8570 return finish_call_expr (function, call_args,
8571 /*disallow_virtual=*/qualified_p,
8576 return build_x_conditional_expr
8577 (RECUR (TREE_OPERAND (t, 0)),
8578 RECUR (TREE_OPERAND (t, 1)),
8579 RECUR (TREE_OPERAND (t, 2)));
8581 case PSEUDO_DTOR_EXPR:
8582 return finish_pseudo_destructor_expr
8583 (RECUR (TREE_OPERAND (t, 0)),
8584 RECUR (TREE_OPERAND (t, 1)),
8585 RECUR (TREE_OPERAND (t, 2)));
8589 tree purpose, value, chain;
8591 if (t == void_list_node)
8594 purpose = TREE_PURPOSE (t);
8596 purpose = RECUR (purpose);
8597 value = TREE_VALUE (t);
8599 value = RECUR (value);
8600 chain = TREE_CHAIN (t);
8601 if (chain && chain != void_type_node)
8602 chain = RECUR (chain);
8603 if (purpose == TREE_PURPOSE (t)
8604 && value == TREE_VALUE (t)
8605 && chain == TREE_CHAIN (t))
8607 return tree_cons (purpose, value, chain);
8615 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8616 args, complain, in_decl);
8617 /* Remember that there was a reference to this entity. */
8618 if (DECL_P (object))
8621 member = TREE_OPERAND (t, 1);
8622 if (BASELINK_P (member))
8623 member = tsubst_baselink (member,
8624 non_reference (TREE_TYPE (object)),
8625 args, complain, in_decl);
8627 member = tsubst_copy (member, args, complain, in_decl);
8629 if (!CLASS_TYPE_P (TREE_TYPE (object)))
8631 if (TREE_CODE (member) == BIT_NOT_EXPR)
8632 return finish_pseudo_destructor_expr (object,
8634 TREE_TYPE (object));
8635 else if (TREE_CODE (member) == SCOPE_REF
8636 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8637 return finish_pseudo_destructor_expr (object,
8639 TREE_TYPE (object));
8641 else if (TREE_CODE (member) == SCOPE_REF
8642 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8647 /* Lookup the template functions now that we know what the
8649 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8650 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8651 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8652 /*is_type_p=*/false,
8653 /*complain=*/false);
8654 if (BASELINK_P (member))
8655 BASELINK_FUNCTIONS (member)
8656 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8660 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8662 return error_mark_node;
8665 else if (TREE_CODE (member) == SCOPE_REF
8666 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8667 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8669 if (complain & tf_error)
8671 if (TYPE_P (TREE_OPERAND (member, 0)))
8672 error ("%qT is not a class or namespace",
8673 TREE_OPERAND (member, 0));
8675 error ("%qD is not a class or namespace",
8676 TREE_OPERAND (member, 0));
8678 return error_mark_node;
8680 else if (TREE_CODE (member) == FIELD_DECL)
8681 return finish_non_static_data_member (member, object, NULL_TREE);
8683 return finish_class_member_access_expr (object, member);
8688 (RECUR (TREE_OPERAND (t, 0)));
8694 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8697 /* digest_init will do the wrong thing if we let it. */
8698 if (type && TYPE_PTRMEMFUNC_P (type))
8702 /* We do not want to process the purpose of aggregate
8703 initializers as they are identifier nodes which will be
8704 looked up by digest_init. */
8705 purpose_p = !(type && IS_AGGR_TYPE (type));
8706 for (elts = CONSTRUCTOR_ELTS (t);
8708 elts = TREE_CHAIN (elts))
8710 tree purpose = TREE_PURPOSE (elts);
8711 tree value = TREE_VALUE (elts);
8713 if (purpose && purpose_p)
8714 purpose = RECUR (purpose);
8715 value = RECUR (value);
8716 r = tree_cons (purpose, value, r);
8719 r = build_constructor (NULL_TREE, nreverse (r));
8720 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8723 return digest_init (type, r, 0);
8729 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8730 if (TYPE_P (operand_0))
8731 return get_typeid (operand_0);
8732 return build_typeid (operand_0);
8736 return convert_from_reference (tsubst_copy (t, args, complain, in_decl));
8740 t = tsubst_copy (t, args, complain, in_decl);
8741 return convert_from_reference (t);
8744 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8745 tsubst_copy (TREE_TYPE (t), args, complain,
8749 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8753 tree old_stmt_expr = cur_stmt_expr;
8754 tree stmt_expr = begin_stmt_expr ();
8756 cur_stmt_expr = stmt_expr;
8757 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8758 stmt_expr = finish_stmt_expr (stmt_expr, false);
8759 cur_stmt_expr = old_stmt_expr;
8765 t = tsubst_copy (t, args, complain, in_decl);
8766 /* As in finish_id_expression, we resolve enumeration constants
8767 to their underlying values. */
8768 if (TREE_CODE (t) == CONST_DECL)
8769 return DECL_INITIAL (t);
8773 return tsubst_copy (t, args, complain, in_decl);
8779 /* Verify that the instantiated ARGS are valid. For type arguments,
8780 make sure that the type's linkage is ok. For non-type arguments,
8781 make sure they are constants if they are integral or enumerations.
8782 Emit an error under control of COMPLAIN, and return TRUE on error. */
8785 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8787 int ix, len = DECL_NTPARMS (tmpl);
8788 bool result = false;
8790 for (ix = 0; ix != len; ix++)
8792 tree t = TREE_VEC_ELT (args, ix);
8796 /* [basic.link]: A name with no linkage (notably, the name
8797 of a class or enumeration declared in a local scope)
8798 shall not be used to declare an entity with linkage.
8799 This implies that names with no linkage cannot be used as
8800 template arguments. */
8801 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8805 if (!(complain & tf_error))
8807 else if (TYPE_ANONYMOUS_P (nt))
8808 error ("%qT uses anonymous type", t);
8810 error ("%qT uses local type %qT", t, nt);
8813 /* In order to avoid all sorts of complications, we do not
8814 allow variably-modified types as template arguments. */
8815 else if (variably_modified_type_p (t, NULL_TREE))
8817 if (complain & tf_error)
8818 error ("%qT is a variably modified type", t);
8822 /* A non-type argument of integral or enumerated type must be a
8824 else if (TREE_TYPE (t)
8825 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8826 && !TREE_CONSTANT (t))
8828 if (complain & tf_error)
8829 error ("integral expression %qE is not constant", t);
8833 if (result && complain & tf_error)
8834 error (" trying to instantiate %qD", tmpl);
8838 /* Instantiate the indicated variable or function template TMPL with
8839 the template arguments in TARG_PTR. */
8842 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8848 if (tmpl == error_mark_node)
8849 return error_mark_node;
8851 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
8853 /* If this function is a clone, handle it specially. */
8854 if (DECL_CLONED_FUNCTION_P (tmpl))
8859 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8861 if (spec == error_mark_node)
8862 return error_mark_node;
8864 /* Look for the clone. */
8865 FOR_EACH_CLONE (clone, spec)
8866 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8868 /* We should always have found the clone by now. */
8873 /* Check to see if we already have this specialization. */
8874 spec = retrieve_specialization (tmpl, targ_ptr,
8875 /*class_specializations_p=*/false);
8876 if (spec != NULL_TREE)
8879 gen_tmpl = most_general_template (tmpl);
8880 if (tmpl != gen_tmpl)
8882 /* The TMPL is a partial instantiation. To get a full set of
8883 arguments we must add the arguments used to perform the
8884 partial instantiation. */
8885 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
8888 /* Check to see if we already have this specialization. */
8889 spec = retrieve_specialization (gen_tmpl, targ_ptr,
8890 /*class_specializations_p=*/false);
8891 if (spec != NULL_TREE)
8895 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
8897 return error_mark_node;
8899 /* We are building a FUNCTION_DECL, during which the access of its
8900 parameters and return types have to be checked. However this
8901 FUNCTION_DECL which is the desired context for access checking
8902 is not built yet. We solve this chicken-and-egg problem by
8903 deferring all checks until we have the FUNCTION_DECL. */
8904 push_deferring_access_checks (dk_deferred);
8906 /* Substitute template parameters. */
8907 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
8908 targ_ptr, complain, gen_tmpl);
8910 /* Now we know the specialization, compute access previously
8912 push_access_scope (fndecl);
8913 perform_deferred_access_checks ();
8914 pop_access_scope (fndecl);
8915 pop_deferring_access_checks ();
8917 /* The DECL_TI_TEMPLATE should always be the immediate parent
8918 template, not the most general template. */
8919 DECL_TI_TEMPLATE (fndecl) = tmpl;
8921 /* If we've just instantiated the main entry point for a function,
8922 instantiate all the alternate entry points as well. We do this
8923 by cloning the instantiation of the main entry point, not by
8924 instantiating the template clones. */
8925 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
8926 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
8931 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8932 arguments that are being used when calling it. TARGS is a vector
8933 into which the deduced template arguments are placed.
8935 Return zero for success, 2 for an incomplete match that doesn't resolve
8936 all the types, and 1 for complete failure. An error message will be
8937 printed only for an incomplete match.
8939 If FN is a conversion operator, or we are trying to produce a specific
8940 specialization, RETURN_TYPE is the return type desired.
8942 The EXPLICIT_TARGS are explicit template arguments provided via a
8945 The parameter STRICT is one of:
8948 We are deducing arguments for a function call, as in
8952 We are deducing arguments for a conversion function, as in
8956 We are deducing arguments when doing an explicit instantiation
8957 as in [temp.explicit], when determining an explicit specialization
8958 as in [temp.expl.spec], or when taking the address of a function
8959 template, as in [temp.deduct.funcaddr].
8962 We are deducing arguments when calculating the partial
8963 ordering between specializations of function or class
8964 templates, as in [temp.func.order] and [temp.class.order].
8966 LEN is the number of parms to consider before returning success, or -1
8967 for all. This is used in partial ordering to avoid comparing parms for
8968 which no actual argument was passed, since they are not considered in
8969 overload resolution (and are explicitly excluded from consideration in
8970 partial ordering in [temp.func.order]/6). */
8973 fn_type_unification (tree fn,
8974 tree explicit_targs,
8978 unification_kind_t strict,
8985 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
8987 fntype = TREE_TYPE (fn);
8992 The specified template arguments must match the template
8993 parameters in kind (i.e., type, nontype, template), and there
8994 must not be more arguments than there are parameters;
8995 otherwise type deduction fails.
8997 Nontype arguments must match the types of the corresponding
8998 nontype template parameters, or must be convertible to the
8999 types of the corresponding nontype parameters as specified in
9000 _temp.arg.nontype_, otherwise type deduction fails.
9002 All references in the function type of the function template
9003 to the corresponding template parameters are replaced by the
9004 specified template argument values. If a substitution in a
9005 template parameter or in the function type of the function
9006 template results in an invalid type, type deduction fails. */
9008 tree converted_args;
9012 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9013 explicit_targs, NULL_TREE, tf_none,
9014 /*require_all_arguments=*/0));
9015 if (converted_args == error_mark_node)
9018 /* Substitute the explicit args into the function type. This is
9019 necessary so that, for instance, explicitly declared function
9020 arguments can match null pointed constants. If we were given
9021 an incomplete set of explicit args, we must not do semantic
9022 processing during substitution as we could create partial
9024 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9025 processing_template_decl += incomplete;
9026 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9027 processing_template_decl -= incomplete;
9029 if (fntype == error_mark_node)
9032 /* Place the explicitly specified arguments in TARGS. */
9033 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9034 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9037 parms = TYPE_ARG_TYPES (fntype);
9038 /* Never do unification on the 'this' parameter. */
9039 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9040 parms = TREE_CHAIN (parms);
9044 /* We've been given a return type to match, prepend it. */
9045 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9046 args = tree_cons (NULL_TREE, return_type, args);
9051 /* We allow incomplete unification without an error message here
9052 because the standard doesn't seem to explicitly prohibit it. Our
9053 callers must be ready to deal with unification failures in any
9055 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9056 targs, parms, args, /*subr=*/0,
9057 strict, /*allow_incomplete*/1, len);
9060 /* All is well so far. Now, check:
9064 When all template arguments have been deduced, all uses of
9065 template parameters in nondeduced contexts are replaced with
9066 the corresponding deduced argument values. If the
9067 substitution results in an invalid type, as described above,
9068 type deduction fails. */
9069 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9076 /* Adjust types before performing type deduction, as described in
9077 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9078 sections are symmetric. PARM is the type of a function parameter
9079 or the return type of the conversion function. ARG is the type of
9080 the argument passed to the call, or the type of the value
9081 initialized with the result of the conversion function. */
9084 maybe_adjust_types_for_deduction (unification_kind_t strict,
9097 /* Swap PARM and ARG throughout the remainder of this
9098 function; the handling is precisely symmetric since PARM
9099 will initialize ARG rather than vice versa. */
9107 /* There is nothing to do in this case. */
9111 /* DR 214. [temp.func.order] is underspecified, and leads to no
9112 ordering between things like `T *' and `T const &' for `U *'.
9113 The former has T=U and the latter T=U*. The former looks more
9114 specialized and John Spicer considers it well-formed (the EDG
9115 compiler accepts it).
9117 John also confirms that deduction should proceed as in a function
9118 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
9119 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
9120 to an actual call can have such a type.
9122 If both ARG and PARM are REFERENCE_TYPE, we change neither.
9123 If only ARG is a REFERENCE_TYPE, we look through that and then
9124 proceed as with DEDUCE_CALL (which could further convert it). */
9125 if (TREE_CODE (*arg) == REFERENCE_TYPE)
9127 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9129 *arg = TREE_TYPE (*arg);
9136 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9138 /* [temp.deduct.call]
9140 If P is not a reference type:
9142 --If A is an array type, the pointer type produced by the
9143 array-to-pointer standard conversion (_conv.array_) is
9144 used in place of A for type deduction; otherwise,
9146 --If A is a function type, the pointer type produced by
9147 the function-to-pointer standard conversion
9148 (_conv.func_) is used in place of A for type deduction;
9151 --If A is a cv-qualified type, the top level
9152 cv-qualifiers of A's type are ignored for type
9154 if (TREE_CODE (*arg) == ARRAY_TYPE)
9155 *arg = build_pointer_type (TREE_TYPE (*arg));
9156 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9157 *arg = build_pointer_type (*arg);
9159 *arg = TYPE_MAIN_VARIANT (*arg);
9162 /* [temp.deduct.call]
9164 If P is a cv-qualified type, the top level cv-qualifiers
9165 of P's type are ignored for type deduction. If P is a
9166 reference type, the type referred to by P is used for
9168 *parm = TYPE_MAIN_VARIANT (*parm);
9169 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9171 *parm = TREE_TYPE (*parm);
9172 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9175 /* DR 322. For conversion deduction, remove a reference type on parm
9176 too (which has been swapped into ARG). */
9177 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9178 *arg = TREE_TYPE (*arg);
9183 /* Most parms like fn_type_unification.
9185 If SUBR is 1, we're being called recursively (to unify the
9186 arguments of a function or method parameter of a function
9190 type_unification_real (tree tparms,
9195 unification_kind_t strict,
9196 int allow_incomplete,
9201 int ntparms = TREE_VEC_LENGTH (tparms);
9203 int saw_undeduced = 0;
9207 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9208 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9209 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9210 gcc_assert (ntparms > 0);
9215 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9216 | UNIFY_ALLOW_DERIVED);
9220 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9224 sub_strict = UNIFY_ALLOW_NONE;
9228 sub_strict = UNIFY_ALLOW_NONE;
9244 && parms != void_list_node
9246 && args != void_list_node)
9248 parm = TREE_VALUE (parms);
9249 parms = TREE_CHAIN (parms);
9250 arg = TREE_VALUE (args);
9251 args = TREE_CHAIN (args);
9253 if (arg == error_mark_node)
9255 if (arg == unknown_type_node)
9256 /* We can't deduce anything from this, but we might get all the
9257 template args from other function args. */
9260 /* Conversions will be performed on a function argument that
9261 corresponds with a function parameter that contains only
9262 non-deducible template parameters and explicitly specified
9263 template parameters. */
9264 if (!uses_template_parms (parm))
9269 type = TREE_TYPE (arg);
9273 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
9275 if (same_type_p (parm, type))
9279 /* It might work; we shouldn't check now, because we might
9280 get into infinite recursion. Overload resolution will
9289 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9290 if (type_unknown_p (arg))
9292 /* [temp.deduct.type] A template-argument can be deduced from
9293 a pointer to function or pointer to member function
9294 argument if the set of overloaded functions does not
9295 contain function templates and at most one of a set of
9296 overloaded functions provides a unique match. */
9298 if (resolve_overloaded_unification
9299 (tparms, targs, parm, arg, strict, sub_strict)
9304 arg = TREE_TYPE (arg);
9305 if (arg == error_mark_node)
9310 int arg_strict = sub_strict;
9313 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9315 if (unify (tparms, targs, parm, arg, arg_strict))
9319 /* Are we done with the interesting parms? */
9323 /* Fail if we've reached the end of the parm list, and more args
9324 are present, and the parm list isn't variadic. */
9325 if (args && args != void_list_node && parms == void_list_node)
9327 /* Fail if parms are left and they don't have default values. */
9329 && parms != void_list_node
9330 && TREE_PURPOSE (parms) == NULL_TREE)
9335 for (i = 0; i < ntparms; i++)
9336 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
9338 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9340 /* If this is an undeduced nontype parameter that depends on
9341 a type parameter, try another pass; its type may have been
9342 deduced from a later argument than the one from which
9343 this parameter can be deduced. */
9344 if (TREE_CODE (tparm) == PARM_DECL
9345 && uses_template_parms (TREE_TYPE (tparm))
9346 && !saw_undeduced++)
9349 if (!allow_incomplete)
9350 error ("incomplete type unification");
9356 /* Subroutine of type_unification_real. Args are like the variables at the
9357 call site. ARG is an overloaded function (or template-id); we try
9358 deducing template args from each of the overloads, and if only one
9359 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9362 resolve_overloaded_unification (tree tparms,
9366 unification_kind_t strict,
9369 tree tempargs = copy_node (targs);
9373 if (TREE_CODE (arg) == ADDR_EXPR)
9375 arg = TREE_OPERAND (arg, 0);
9381 if (TREE_CODE (arg) == COMPONENT_REF)
9382 /* Handle `&x' where `x' is some static or non-static member
9384 arg = TREE_OPERAND (arg, 1);
9386 if (TREE_CODE (arg) == OFFSET_REF)
9387 arg = TREE_OPERAND (arg, 1);
9389 /* Strip baselink information. */
9390 if (BASELINK_P (arg))
9391 arg = BASELINK_FUNCTIONS (arg);
9393 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9395 /* If we got some explicit template args, we need to plug them into
9396 the affected templates before we try to unify, in case the
9397 explicit args will completely resolve the templates in question. */
9399 tree expl_subargs = TREE_OPERAND (arg, 1);
9400 arg = TREE_OPERAND (arg, 0);
9402 for (; arg; arg = OVL_NEXT (arg))
9404 tree fn = OVL_CURRENT (arg);
9407 if (TREE_CODE (fn) != TEMPLATE_DECL)
9410 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
9414 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9415 good += try_one_overload (tparms, targs, tempargs, parm,
9416 elem, strict, sub_strict, addr_p);
9422 gcc_assert (TREE_CODE (arg) == OVERLOAD
9423 || TREE_CODE (arg) == FUNCTION_DECL);
9425 for (; arg; arg = OVL_NEXT (arg))
9426 good += try_one_overload (tparms, targs, tempargs, parm,
9427 TREE_TYPE (OVL_CURRENT (arg)),
9428 strict, sub_strict, addr_p);
9431 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9432 to function or pointer to member function argument if the set of
9433 overloaded functions does not contain function templates and at most
9434 one of a set of overloaded functions provides a unique match.
9436 So if we found multiple possibilities, we return success but don't
9441 int i = TREE_VEC_LENGTH (targs);
9443 if (TREE_VEC_ELT (tempargs, i))
9444 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9452 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9453 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9454 different overloads deduce different arguments for a given parm.
9455 ADDR_P is true if the expression for which deduction is being
9456 performed was of the form "& fn" rather than simply "fn".
9458 Returns 1 on success. */
9461 try_one_overload (tree tparms,
9466 unification_kind_t strict,
9474 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9475 to function or pointer to member function argument if the set of
9476 overloaded functions does not contain function templates and at most
9477 one of a set of overloaded functions provides a unique match.
9479 So if this is a template, just return success. */
9481 if (uses_template_parms (arg))
9484 if (TREE_CODE (arg) == METHOD_TYPE)
9485 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9487 arg = build_pointer_type (arg);
9489 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9491 /* We don't copy orig_targs for this because if we have already deduced
9492 some template args from previous args, unify would complain when we
9493 try to deduce a template parameter for the same argument, even though
9494 there isn't really a conflict. */
9495 nargs = TREE_VEC_LENGTH (targs);
9496 tempargs = make_tree_vec (nargs);
9498 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9501 /* First make sure we didn't deduce anything that conflicts with
9502 explicitly specified args. */
9503 for (i = nargs; i--; )
9505 tree elt = TREE_VEC_ELT (tempargs, i);
9506 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9508 if (elt == NULL_TREE)
9510 else if (uses_template_parms (elt))
9512 /* Since we're unifying against ourselves, we will fill in template
9513 args used in the function parm list with our own template parms.
9515 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9518 else if (oldelt && ! template_args_equal (oldelt, elt))
9522 for (i = nargs; i--; )
9524 tree elt = TREE_VEC_ELT (tempargs, i);
9527 TREE_VEC_ELT (targs, i) = elt;
9533 /* Verify that nondeduce template argument agrees with the type
9534 obtained from argument deduction. Return nonzero if the
9539 struct A { typedef int X; };
9540 template <class T, class U> struct C {};
9541 template <class T> struct C<T, typename T::X> {};
9543 Then with the instantiation `C<A, int>', we can deduce that
9544 `T' is `A' but unify () does not check whether `typename T::X'
9545 is `int'. This function ensure that they agree.
9547 TARGS, PARMS are the same as the arguments of unify.
9548 ARGS contains template arguments from all levels. */
9551 verify_class_unification (tree targs, tree parms, tree args)
9553 parms = tsubst (parms, add_outermost_template_args (args, targs),
9554 tf_none, NULL_TREE);
9555 if (parms == error_mark_node)
9558 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9561 /* PARM is a template class (perhaps with unbound template
9562 parameters). ARG is a fully instantiated type. If ARG can be
9563 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9564 TARGS are as for unify. */
9567 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9571 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9572 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9573 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9576 /* We need to make a new template argument vector for the call to
9577 unify. If we used TARGS, we'd clutter it up with the result of
9578 the attempted unification, even if this class didn't work out.
9579 We also don't want to commit ourselves to all the unifications
9580 we've already done, since unification is supposed to be done on
9581 an argument-by-argument basis. In other words, consider the
9582 following pathological case:
9584 template <int I, int J, int K>
9587 template <int I, int J>
9588 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9590 template <int I, int J, int K>
9591 void f(S<I, J, K>, S<I, I, I>);
9600 Now, by the time we consider the unification involving `s2', we
9601 already know that we must have `f<0, 0, 0>'. But, even though
9602 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9603 because there are two ways to unify base classes of S<0, 1, 2>
9604 with S<I, I, I>. If we kept the already deduced knowledge, we
9605 would reject the possibility I=1. */
9606 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9608 /* If unification failed, we're done. */
9609 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9610 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9616 /* Given a template type PARM and a class type ARG, find the unique
9617 base type in ARG that is an instance of PARM. We do not examine
9618 ARG itself; only its base-classes. If there is not exactly one
9619 appropriate base class, return NULL_TREE. PARM may be the type of
9620 a partial specialization, as well as a plain template type. Used
9624 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9626 tree rval = NULL_TREE;
9629 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9631 binfo = TYPE_BINFO (complete_type (arg));
9633 /* The type could not be completed. */
9636 /* Walk in inheritance graph order. The search order is not
9637 important, and this avoids multiple walks of virtual bases. */
9638 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9640 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9644 /* If there is more than one satisfactory baseclass, then:
9648 If they yield more than one possible deduced A, the type
9652 if (rval && !same_type_p (r, rval))
9662 /* Returns the level of DECL, which declares a template parameter. */
9665 template_decl_level (tree decl)
9667 switch (TREE_CODE (decl))
9671 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9674 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9682 /* Decide whether ARG can be unified with PARM, considering only the
9683 cv-qualifiers of each type, given STRICT as documented for unify.
9684 Returns nonzero iff the unification is OK on that basis. */
9687 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9689 int arg_quals = cp_type_quals (arg);
9690 int parm_quals = cp_type_quals (parm);
9692 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9693 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9695 /* Although a CVR qualifier is ignored when being applied to a
9696 substituted template parameter ([8.3.2]/1 for example), that
9697 does not apply during deduction [14.8.2.4]/1, (even though
9698 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9699 this). Except when we're allowing additional CV qualifiers
9700 at the outer level [14.8.2.1]/3,1st bullet. */
9701 if ((TREE_CODE (arg) == REFERENCE_TYPE
9702 || TREE_CODE (arg) == FUNCTION_TYPE
9703 || TREE_CODE (arg) == METHOD_TYPE)
9704 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9707 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9708 && (parm_quals & TYPE_QUAL_RESTRICT))
9712 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9713 && (arg_quals & parm_quals) != parm_quals)
9716 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9717 && (parm_quals & arg_quals) != arg_quals)
9723 /* Takes parameters as for type_unification. Returns 0 if the
9724 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9725 bitwise or of the following flags:
9728 Require an exact match between PARM and ARG.
9729 UNIFY_ALLOW_MORE_CV_QUAL:
9730 Allow the deduced ARG to be more cv-qualified (by qualification
9731 conversion) than ARG.
9732 UNIFY_ALLOW_LESS_CV_QUAL:
9733 Allow the deduced ARG to be less cv-qualified than ARG.
9734 UNIFY_ALLOW_DERIVED:
9735 Allow the deduced ARG to be a template base class of ARG,
9736 or a pointer to a template base class of the type pointed to by
9738 UNIFY_ALLOW_INTEGER:
9739 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9740 case for more information.
9741 UNIFY_ALLOW_OUTER_LEVEL:
9742 This is the outermost level of a deduction. Used to determine validity
9743 of qualification conversions. A valid qualification conversion must
9744 have const qualified pointers leading up to the inner type which
9745 requires additional CV quals, except at the outer level, where const
9746 is not required [conv.qual]. It would be normal to set this flag in
9747 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9748 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9749 This is the outermost level of a deduction, and PARM can be more CV
9750 qualified at this point.
9751 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9752 This is the outermost level of a deduction, and PARM can be less CV
9753 qualified at this point. */
9756 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9761 int strict_in = strict;
9763 /* I don't think this will do the right thing with respect to types.
9764 But the only case I've seen it in so far has been array bounds, where
9765 signedness is the only information lost, and I think that will be
9767 while (TREE_CODE (parm) == NOP_EXPR)
9768 parm = TREE_OPERAND (parm, 0);
9770 if (arg == error_mark_node)
9772 if (arg == unknown_type_node)
9773 /* We can't deduce anything from this, but we might get all the
9774 template args from other function args. */
9777 /* If PARM uses template parameters, then we can't bail out here,
9778 even if ARG == PARM, since we won't record unifications for the
9779 template parameters. We might need them if we're trying to
9780 figure out which of two things is more specialized. */
9781 if (arg == parm && !uses_template_parms (parm))
9784 /* Immediately reject some pairs that won't unify because of
9785 cv-qualification mismatches. */
9786 if (TREE_CODE (arg) == TREE_CODE (parm)
9788 /* It is the elements of the array which hold the cv quals of an array
9789 type, and the elements might be template type parms. We'll check
9791 && TREE_CODE (arg) != ARRAY_TYPE
9792 /* We check the cv-qualifiers when unifying with template type
9793 parameters below. We want to allow ARG `const T' to unify with
9794 PARM `T' for example, when computing which of two templates
9795 is more specialized, for example. */
9796 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9797 && !check_cv_quals_for_unify (strict_in, arg, parm))
9800 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9801 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9802 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9803 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9804 strict &= ~UNIFY_ALLOW_DERIVED;
9805 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9806 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9808 switch (TREE_CODE (parm))
9812 case UNBOUND_CLASS_TEMPLATE:
9813 /* In a type which contains a nested-name-specifier, template
9814 argument values cannot be deduced for template parameters used
9815 within the nested-name-specifier. */
9818 case TEMPLATE_TYPE_PARM:
9819 case TEMPLATE_TEMPLATE_PARM:
9820 case BOUND_TEMPLATE_TEMPLATE_PARM:
9821 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9823 if (TEMPLATE_TYPE_LEVEL (parm)
9824 != template_decl_level (tparm))
9825 /* The PARM is not one we're trying to unify. Just check
9826 to see if it matches ARG. */
9827 return (TREE_CODE (arg) == TREE_CODE (parm)
9828 && same_type_p (parm, arg)) ? 0 : 1;
9829 idx = TEMPLATE_TYPE_IDX (parm);
9830 targ = TREE_VEC_ELT (targs, idx);
9831 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9833 /* Check for mixed types and values. */
9834 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9835 && TREE_CODE (tparm) != TYPE_DECL)
9836 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9837 && TREE_CODE (tparm) != TEMPLATE_DECL))
9840 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9842 /* ARG must be constructed from a template class or a template
9843 template parameter. */
9844 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9845 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9849 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9850 tree parmvec = TYPE_TI_ARGS (parm);
9851 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9853 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9856 /* The parameter and argument roles have to be switched here
9857 in order to handle default arguments properly. For example,
9858 template<template <class> class TT> void f(TT<int>)
9859 should be able to accept vector<int> which comes from
9860 template <class T, class Allocator = allocator>
9863 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9867 /* Deduce arguments T, i from TT<T> or TT<i>.
9868 We check each element of PARMVEC and ARGVEC individually
9869 rather than the whole TREE_VEC since they can have
9870 different number of elements. */
9872 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9874 if (unify (tparms, targs,
9875 TREE_VEC_ELT (parmvec, i),
9876 TREE_VEC_ELT (argvec, i),
9881 arg = TYPE_TI_TEMPLATE (arg);
9883 /* Fall through to deduce template name. */
9886 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9887 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9889 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9891 /* Simple cases: Value already set, does match or doesn't. */
9892 if (targ != NULL_TREE && template_args_equal (targ, arg))
9899 /* If PARM is `const T' and ARG is only `int', we don't have
9900 a match unless we are allowing additional qualification.
9901 If ARG is `const int' and PARM is just `T' that's OK;
9902 that binds `const int' to `T'. */
9903 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
9907 /* Consider the case where ARG is `const volatile int' and
9908 PARM is `const T'. Then, T should be `volatile int'. */
9909 arg = cp_build_qualified_type_real
9910 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
9911 if (arg == error_mark_node)
9914 /* Simple cases: Value already set, does match or doesn't. */
9915 if (targ != NULL_TREE && same_type_p (targ, arg))
9920 /* Make sure that ARG is not a variable-sized array. (Note
9921 that were talking about variable-sized arrays (like
9922 `int[n]'), rather than arrays of unknown size (like
9923 `int[]').) We'll get very confused by such a type since
9924 the bound of the array will not be computable in an
9925 instantiation. Besides, such types are not allowed in
9926 ISO C++, so we can do as we please here. */
9927 if (variably_modified_type_p (arg, NULL_TREE))
9931 TREE_VEC_ELT (targs, idx) = arg;
9934 case TEMPLATE_PARM_INDEX:
9935 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9937 if (TEMPLATE_PARM_LEVEL (parm)
9938 != template_decl_level (tparm))
9939 /* The PARM is not one we're trying to unify. Just check
9940 to see if it matches ARG. */
9941 return !(TREE_CODE (arg) == TREE_CODE (parm)
9942 && cp_tree_equal (parm, arg));
9944 idx = TEMPLATE_PARM_IDX (parm);
9945 targ = TREE_VEC_ELT (targs, idx);
9948 return !cp_tree_equal (targ, arg);
9950 /* [temp.deduct.type] If, in the declaration of a function template
9951 with a non-type template-parameter, the non-type
9952 template-parameter is used in an expression in the function
9953 parameter-list and, if the corresponding template-argument is
9954 deduced, the template-argument type shall match the type of the
9955 template-parameter exactly, except that a template-argument
9956 deduced from an array bound may be of any integral type.
9957 The non-type parameter might use already deduced type parameters. */
9958 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
9959 if (!TREE_TYPE (arg))
9960 /* Template-parameter dependent expression. Just accept it for now.
9961 It will later be processed in convert_template_argument. */
9963 else if (same_type_p (TREE_TYPE (arg), tparm))
9965 else if ((strict & UNIFY_ALLOW_INTEGER)
9966 && (TREE_CODE (tparm) == INTEGER_TYPE
9967 || TREE_CODE (tparm) == BOOLEAN_TYPE))
9968 /* Convert the ARG to the type of PARM; the deduced non-type
9969 template argument must exactly match the types of the
9970 corresponding parameter. */
9971 arg = fold (build_nop (TREE_TYPE (parm), arg));
9972 else if (uses_template_parms (tparm))
9973 /* We haven't deduced the type of this parameter yet. Try again
9979 TREE_VEC_ELT (targs, idx) = arg;
9984 /* A pointer-to-member constant can be unified only with
9985 another constant. */
9986 if (TREE_CODE (arg) != PTRMEM_CST)
9989 /* Just unify the class member. It would be useless (and possibly
9990 wrong, depending on the strict flags) to unify also
9991 PTRMEM_CST_CLASS, because we want to be sure that both parm and
9992 arg refer to the same variable, even if through different
9993 classes. For instance:
9995 struct A { int x; };
9998 Unification of &A::x and &B::x must succeed. */
9999 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10000 PTRMEM_CST_MEMBER (arg), strict);
10005 if (TREE_CODE (arg) != POINTER_TYPE)
10008 /* [temp.deduct.call]
10010 A can be another pointer or pointer to member type that can
10011 be converted to the deduced A via a qualification
10012 conversion (_conv.qual_).
10014 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10015 This will allow for additional cv-qualification of the
10016 pointed-to types if appropriate. */
10018 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10019 /* The derived-to-base conversion only persists through one
10020 level of pointers. */
10021 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10023 return unify (tparms, targs, TREE_TYPE (parm),
10024 TREE_TYPE (arg), strict);
10027 case REFERENCE_TYPE:
10028 if (TREE_CODE (arg) != REFERENCE_TYPE)
10030 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10031 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10034 if (TREE_CODE (arg) != ARRAY_TYPE)
10036 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10037 != (TYPE_DOMAIN (arg) == NULL_TREE))
10039 if (TYPE_DOMAIN (parm) != NULL_TREE)
10044 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10045 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10047 /* Our representation of array types uses "N - 1" as the
10048 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10049 not an integer constant. */
10050 if (TREE_CODE (parm_max) == MINUS_EXPR)
10052 arg_max = fold (build2 (PLUS_EXPR,
10055 TREE_OPERAND (parm_max, 1)));
10056 parm_max = TREE_OPERAND (parm_max, 0);
10059 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10062 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10063 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10070 case ENUMERAL_TYPE:
10072 if (TREE_CODE (arg) != TREE_CODE (parm))
10075 /* We have already checked cv-qualification at the top of the
10077 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10080 /* As far as unification is concerned, this wins. Later checks
10081 will invalidate it if necessary. */
10084 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10085 /* Type INTEGER_CST can come from ordinary constant template args. */
10087 while (TREE_CODE (arg) == NOP_EXPR)
10088 arg = TREE_OPERAND (arg, 0);
10090 if (TREE_CODE (arg) != INTEGER_CST)
10092 return !tree_int_cst_equal (parm, arg);
10097 if (TREE_CODE (arg) != TREE_VEC)
10099 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10101 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10102 if (unify (tparms, targs,
10103 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10111 if (TREE_CODE (arg) != TREE_CODE (parm))
10114 if (TYPE_PTRMEMFUNC_P (parm))
10116 if (!TYPE_PTRMEMFUNC_P (arg))
10119 return unify (tparms, targs,
10120 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10121 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10125 if (CLASSTYPE_TEMPLATE_INFO (parm))
10127 tree t = NULL_TREE;
10129 if (strict_in & UNIFY_ALLOW_DERIVED)
10131 /* First, we try to unify the PARM and ARG directly. */
10132 t = try_class_unification (tparms, targs,
10137 /* Fallback to the special case allowed in
10138 [temp.deduct.call]:
10140 If P is a class, and P has the form
10141 template-id, then A can be a derived class of
10142 the deduced A. Likewise, if P is a pointer to
10143 a class of the form template-id, A can be a
10144 pointer to a derived class pointed to by the
10146 t = get_template_base (tparms, targs, parm, arg);
10152 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10153 && (CLASSTYPE_TI_TEMPLATE (parm)
10154 == CLASSTYPE_TI_TEMPLATE (arg)))
10155 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10156 Then, we should unify `int' and `U'. */
10159 /* There's no chance of unification succeeding. */
10162 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10163 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10165 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10170 case FUNCTION_TYPE:
10171 if (TREE_CODE (arg) != TREE_CODE (parm))
10174 if (unify (tparms, targs, TREE_TYPE (parm),
10175 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10177 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10178 TYPE_ARG_TYPES (arg), 1,
10179 DEDUCE_EXACT, 0, -1);
10182 if (TREE_CODE (arg) != OFFSET_TYPE)
10184 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10185 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10187 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10191 if (DECL_TEMPLATE_PARM_P (parm))
10192 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10193 if (arg != decl_constant_value (parm))
10198 case TEMPLATE_DECL:
10199 /* Matched cases are handled by the ARG == PARM test above. */
10203 gcc_assert (EXPR_P (parm));
10205 /* We must be looking at an expression. This can happen with
10209 void foo(S<I>, S<I + 2>);
10211 This is a "nondeduced context":
10215 The nondeduced contexts are:
10217 --A type that is a template-id in which one or more of
10218 the template-arguments is an expression that references
10219 a template-parameter.
10221 In these cases, we assume deduction succeeded, but don't
10222 actually infer any unifications. */
10224 if (!uses_template_parms (parm)
10225 && !template_args_equal (parm, arg))
10232 /* Note that DECL can be defined in this translation unit, if
10236 mark_definable (tree decl)
10239 DECL_NOT_REALLY_EXTERN (decl) = 1;
10240 FOR_EACH_CLONE (clone, decl)
10241 DECL_NOT_REALLY_EXTERN (clone) = 1;
10244 /* Called if RESULT is explicitly instantiated, or is a member of an
10245 explicitly instantiated class. */
10248 mark_decl_instantiated (tree result, int extern_p)
10250 SET_DECL_EXPLICIT_INSTANTIATION (result);
10252 /* If this entity has already been written out, it's too late to
10253 make any modifications. */
10254 if (TREE_ASM_WRITTEN (result))
10257 if (TREE_CODE (result) != FUNCTION_DECL)
10258 /* The TREE_PUBLIC flag for function declarations will have been
10259 set correctly by tsubst. */
10260 TREE_PUBLIC (result) = 1;
10262 /* This might have been set by an earlier implicit instantiation. */
10263 DECL_COMDAT (result) = 0;
10266 DECL_NOT_REALLY_EXTERN (result) = 0;
10269 mark_definable (result);
10270 /* Always make artificials weak. */
10271 if (DECL_ARTIFICIAL (result) && flag_weak)
10272 comdat_linkage (result);
10273 /* For WIN32 we also want to put explicit instantiations in
10274 linkonce sections. */
10275 else if (TREE_PUBLIC (result))
10276 maybe_make_one_only (result);
10279 /* If EXTERN_P, then this function will not be emitted -- unless
10280 followed by an explicit instantiation, at which point its linkage
10281 will be adjusted. If !EXTERN_P, then this function will be
10282 emitted here. In neither circumstance do we want
10283 import_export_decl to adjust the linkage. */
10284 DECL_INTERFACE_KNOWN (result) = 1;
10287 /* Given two function templates PAT1 and PAT2, return:
10289 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
10291 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10292 -1 if PAT2 is more specialized than PAT1.
10293 0 if neither is more specialized.
10295 LEN is passed through to fn_type_unification. */
10298 more_specialized (tree pat1, tree pat2, int deduce, int len)
10303 /* If template argument deduction succeeds, we substitute the
10304 resulting arguments into non-deduced contexts. While doing that,
10305 we must be aware that we may encounter dependent types. */
10306 ++processing_template_decl;
10307 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
10308 NULL_TREE, 0, deduce, len);
10312 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
10313 NULL_TREE, 0, deduce, len);
10316 --processing_template_decl;
10321 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10323 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10324 -1 if PAT2 is more specialized than PAT1.
10325 0 if neither is more specialized.
10327 FULL_ARGS is the full set of template arguments that triggers this
10328 partial ordering. */
10331 more_specialized_class (tree pat1, tree pat2, tree full_args)
10336 /* Just like what happens for functions, if we are ordering between
10337 different class template specializations, we may encounter dependent
10338 types in the arguments, and we need our dependency check functions
10339 to behave correctly. */
10340 ++processing_template_decl;
10341 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10342 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10346 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10347 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10350 --processing_template_decl;
10355 /* Return the template arguments that will produce the function signature
10356 DECL from the function template FN, with the explicit template
10357 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
10358 also match. Return NULL_TREE if no satisfactory arguments could be
10359 found. DEDUCE and LEN are passed through to fn_type_unification. */
10362 get_bindings_real (tree fn,
10364 tree explicit_args,
10369 int ntparms = DECL_NTPARMS (fn);
10370 tree targs = make_tree_vec (ntparms);
10372 tree decl_arg_types;
10375 /* Substitute the explicit template arguments into the type of DECL.
10376 The call to fn_type_unification will handle substitution into the
10378 decl_type = TREE_TYPE (decl);
10379 if (explicit_args && uses_template_parms (decl_type))
10382 tree converted_args;
10384 if (DECL_TEMPLATE_INFO (decl))
10385 tmpl = DECL_TI_TEMPLATE (decl);
10387 /* We can get here for some invalid specializations. */
10391 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10392 explicit_args, NULL_TREE,
10393 tf_none, /*require_all_arguments=*/0));
10394 if (converted_args == error_mark_node)
10397 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10398 if (decl_type == error_mark_node)
10402 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10403 /* Never do unification on the 'this' parameter. */
10404 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10405 decl_arg_types = TREE_CHAIN (decl_arg_types);
10407 i = fn_type_unification (fn, explicit_args, targs,
10409 (check_rettype || DECL_CONV_FN_P (fn)
10410 ? TREE_TYPE (decl_type) : NULL_TREE),
10419 /* For most uses, we want to check the return type. */
10422 get_bindings (tree fn, tree decl, tree explicit_args)
10424 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10427 /* But for resolve_overloaded_unification, we only care about the parameter
10431 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10433 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10436 /* Return the innermost template arguments that, when applied to a
10437 template specialization whose innermost template parameters are
10438 TPARMS, and whose specialization arguments are PARMS, yield the
10441 For example, suppose we have:
10443 template <class T, class U> struct S {};
10444 template <class T> struct S<T*, int> {};
10446 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10447 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10448 int}. The resulting vector will be {double}, indicating that `T'
10449 is bound to `double'. */
10452 get_class_bindings (tree tparms, tree parms, tree args)
10454 int i, ntparms = TREE_VEC_LENGTH (tparms);
10455 tree vec = make_tree_vec (ntparms);
10457 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10461 for (i = 0; i < ntparms; ++i)
10462 if (! TREE_VEC_ELT (vec, i))
10465 if (verify_class_unification (vec, parms, args))
10471 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10472 Pick the most specialized template, and return the corresponding
10473 instantiation, or if there is no corresponding instantiation, the
10474 template itself. If there is no most specialized template,
10475 error_mark_node is returned. If there are no templates at all,
10476 NULL_TREE is returned. */
10479 most_specialized_instantiation (tree instantiations)
10484 if (!instantiations)
10487 champ = instantiations;
10488 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10490 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10498 fn = TREE_CHAIN (fn);
10500 return error_mark_node;
10506 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10508 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10511 return error_mark_node;
10514 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10517 /* Return the most specialized of the list of templates in FNS that can
10518 produce an instantiation matching DECL, given the explicit template
10519 arguments EXPLICIT_ARGS. */
10522 most_specialized (tree fns, tree decl, tree explicit_args)
10524 tree candidates = NULL_TREE;
10527 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10529 tree candidate = TREE_VALUE (fn);
10531 args = get_bindings (candidate, decl, explicit_args);
10533 candidates = tree_cons (NULL_TREE, candidate, candidates);
10536 return most_specialized_instantiation (candidates);
10539 /* If DECL is a specialization of some template, return the most
10540 general such template. Otherwise, returns NULL_TREE.
10542 For example, given:
10544 template <class T> struct S { template <class U> void f(U); };
10546 if TMPL is `template <class U> void S<int>::f(U)' this will return
10547 the full template. This function will not trace past partial
10548 specializations, however. For example, given in addition:
10550 template <class T> struct S<T*> { template <class U> void f(U); };
10552 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10553 `template <class T> template <class U> S<T*>::f(U)'. */
10556 most_general_template (tree decl)
10558 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10559 an immediate specialization. */
10560 if (TREE_CODE (decl) == FUNCTION_DECL)
10562 if (DECL_TEMPLATE_INFO (decl)) {
10563 decl = DECL_TI_TEMPLATE (decl);
10565 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10566 template friend. */
10567 if (TREE_CODE (decl) != TEMPLATE_DECL)
10573 /* Look for more and more general templates. */
10574 while (DECL_TEMPLATE_INFO (decl))
10576 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10577 (See cp-tree.h for details.) */
10578 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10581 if (CLASS_TYPE_P (TREE_TYPE (decl))
10582 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10585 /* Stop if we run into an explicitly specialized class template. */
10586 if (!DECL_NAMESPACE_SCOPE_P (decl)
10587 && DECL_CONTEXT (decl)
10588 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10591 decl = DECL_TI_TEMPLATE (decl);
10597 /* Return the most specialized of the class template specializations
10598 of TMPL which can produce an instantiation matching ARGS, or
10599 error_mark_node if the choice is ambiguous. */
10602 most_specialized_class (tree tmpl, tree args)
10604 tree list = NULL_TREE;
10609 tmpl = most_general_template (tmpl);
10610 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10613 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10616 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10617 TREE_TYPE (list) = TREE_TYPE (t);
10626 t = TREE_CHAIN (t);
10627 for (; t; t = TREE_CHAIN (t))
10629 fate = more_specialized_class (champ, t, args);
10636 t = TREE_CHAIN (t);
10638 return error_mark_node;
10644 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10646 fate = more_specialized_class (champ, t, args);
10648 return error_mark_node;
10654 /* Explicitly instantiate DECL. */
10657 do_decl_instantiation (tree decl, tree storage)
10659 tree result = NULL_TREE;
10663 /* An error occurred, for which grokdeclarator has already issued
10664 an appropriate message. */
10666 else if (! DECL_LANG_SPECIFIC (decl))
10668 error ("explicit instantiation of non-template %q#D", decl);
10671 else if (TREE_CODE (decl) == VAR_DECL)
10673 /* There is an asymmetry here in the way VAR_DECLs and
10674 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10675 the latter, the DECL we get back will be marked as a
10676 template instantiation, and the appropriate
10677 DECL_TEMPLATE_INFO will be set up. This does not happen for
10678 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10679 should handle VAR_DECLs as it currently handles
10681 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10682 if (!result || TREE_CODE (result) != VAR_DECL)
10684 error ("no matching template for %qD found", decl);
10688 else if (TREE_CODE (decl) != FUNCTION_DECL)
10690 error ("explicit instantiation of %q#D", decl);
10696 /* Check for various error cases. Note that if the explicit
10697 instantiation is valid the RESULT will currently be marked as an
10698 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10699 until we get here. */
10701 if (DECL_TEMPLATE_SPECIALIZATION (result))
10703 /* DR 259 [temp.spec].
10705 Both an explicit instantiation and a declaration of an explicit
10706 specialization shall not appear in a program unless the explicit
10707 instantiation follows a declaration of the explicit specialization.
10709 For a given set of template parameters, if an explicit
10710 instantiation of a template appears after a declaration of an
10711 explicit specialization for that template, the explicit
10712 instantiation has no effect. */
10715 else if (DECL_EXPLICIT_INSTANTIATION (result))
10719 No program shall explicitly instantiate any template more
10722 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10723 the first instantiation was `extern' and the second is not,
10724 and EXTERN_P for the opposite case. */
10725 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10726 pedwarn ("duplicate explicit instantiation of %q#D", result);
10727 /* If an "extern" explicit instantiation follows an ordinary
10728 explicit instantiation, the template is instantiated. */
10732 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10734 error ("no matching template for %qD found", result);
10737 else if (!DECL_TEMPLATE_INFO (result))
10739 pedwarn ("explicit instantiation of non-template %q#D", result);
10743 if (storage == NULL_TREE)
10745 else if (storage == ridpointers[(int) RID_EXTERN])
10747 if (pedantic && !in_system_header)
10748 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
10753 error ("storage class %qD applied to template instantiation", storage);
10755 mark_decl_instantiated (result, extern_p);
10757 instantiate_decl (result, /*defer_ok=*/1, /*undefined_ok=*/0);
10761 mark_class_instantiated (tree t, int extern_p)
10763 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10764 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10765 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10766 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10769 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10770 rest_of_type_compilation (t, 1);
10774 /* Called from do_type_instantiation through binding_table_foreach to
10775 do recursive instantiation for the type bound in ENTRY. */
10777 bt_instantiate_type_proc (binding_entry entry, void *data)
10779 tree storage = *(tree *) data;
10781 if (IS_AGGR_TYPE (entry->type)
10782 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10783 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10786 /* Called from do_type_instantiation to instantiate a member
10787 (a member function or a static member variable) of an
10788 explicitly instantiated class template. */
10790 instantiate_class_member (tree decl, int extern_p)
10792 mark_decl_instantiated (decl, extern_p);
10794 instantiate_decl (decl, /*defer_ok=*/1, /* undefined_ok=*/1);
10797 /* Perform an explicit instantiation of template class T. STORAGE, if
10798 non-null, is the RID for extern, inline or static. COMPLAIN is
10799 nonzero if this is called from the parser, zero if called recursively,
10800 since the standard is unclear (as detailed below). */
10803 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10808 int previous_instantiation_extern_p = 0;
10810 if (TREE_CODE (t) == TYPE_DECL)
10813 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10815 error ("explicit instantiation of non-template type %qT", t);
10821 if (!COMPLETE_TYPE_P (t))
10823 if (complain & tf_error)
10824 error ("explicit instantiation of %q#T before definition of template",
10829 if (storage != NULL_TREE)
10831 if (pedantic && !in_system_header)
10832 pedwarn("ISO C++ forbids the use of `%E' on explicit instantiations",
10835 if (storage == ridpointers[(int) RID_INLINE])
10837 else if (storage == ridpointers[(int) RID_EXTERN])
10839 else if (storage == ridpointers[(int) RID_STATIC])
10843 error ("storage class %qD applied to template instantiation",
10849 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10851 /* DR 259 [temp.spec].
10853 Both an explicit instantiation and a declaration of an explicit
10854 specialization shall not appear in a program unless the explicit
10855 instantiation follows a declaration of the explicit specialization.
10857 For a given set of template parameters, if an explicit
10858 instantiation of a template appears after a declaration of an
10859 explicit specialization for that template, the explicit
10860 instantiation has no effect. */
10863 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10867 No program shall explicitly instantiate any template more
10870 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
10871 instantiation was `extern'. If EXTERN_P then the second is.
10872 These cases are OK. */
10873 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
10875 if (!previous_instantiation_extern_p && !extern_p
10876 && (complain & tf_error))
10877 pedwarn ("duplicate explicit instantiation of %q#T", t);
10879 /* If we've already instantiated the template, just return now. */
10880 if (!CLASSTYPE_INTERFACE_ONLY (t))
10884 mark_class_instantiated (t, extern_p);
10892 /* In contrast to implicit instantiation, where only the
10893 declarations, and not the definitions, of members are
10894 instantiated, we have here:
10898 The explicit instantiation of a class template specialization
10899 implies the instantiation of all of its members not
10900 previously explicitly specialized in the translation unit
10901 containing the explicit instantiation.
10903 Of course, we can't instantiate member template classes, since
10904 we don't have any arguments for them. Note that the standard
10905 is unclear on whether the instantiation of the members are
10906 *explicit* instantiations or not. However, the most natural
10907 interpretation is that it should be an explicit instantiation. */
10910 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
10911 if (TREE_CODE (tmp) == FUNCTION_DECL
10912 && DECL_TEMPLATE_INSTANTIATION (tmp))
10913 instantiate_class_member (tmp, extern_p);
10915 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
10916 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
10917 instantiate_class_member (tmp, extern_p);
10919 if (CLASSTYPE_NESTED_UTDS (t))
10920 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
10921 bt_instantiate_type_proc, &storage);
10925 /* Given a function DECL, which is a specialization of TMPL, modify
10926 DECL to be a re-instantiation of TMPL with the same template
10927 arguments. TMPL should be the template into which tsubst'ing
10928 should occur for DECL, not the most general template.
10930 One reason for doing this is a scenario like this:
10933 void f(const T&, int i);
10935 void g() { f(3, 7); }
10938 void f(const T& t, const int i) { }
10940 Note that when the template is first instantiated, with
10941 instantiate_template, the resulting DECL will have no name for the
10942 first parameter, and the wrong type for the second. So, when we go
10943 to instantiate the DECL, we regenerate it. */
10946 regenerate_decl_from_template (tree decl, tree tmpl)
10948 /* The arguments used to instantiate DECL, from the most general
10953 args = DECL_TI_ARGS (decl);
10954 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
10956 /* Make sure that we can see identifiers, and compute access
10958 push_access_scope (decl);
10960 if (TREE_CODE (decl) == FUNCTION_DECL)
10968 args_depth = TMPL_ARGS_DEPTH (args);
10969 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
10970 if (args_depth > parms_depth)
10971 args = get_innermost_template_args (args, parms_depth);
10973 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
10974 args, tf_error, NULL_TREE);
10976 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
10979 /* Merge parameter declarations. */
10980 decl_parm = skip_artificial_parms_for (decl,
10981 DECL_ARGUMENTS (decl));
10983 = skip_artificial_parms_for (code_pattern,
10984 DECL_ARGUMENTS (code_pattern));
10989 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
10990 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
10991 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
10993 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
10994 TREE_TYPE (decl_parm) = parm_type;
10995 decl_parm = TREE_CHAIN (decl_parm);
10996 pattern_parm = TREE_CHAIN (pattern_parm);
10999 /* Merge additional specifiers from the CODE_PATTERN. */
11000 if (DECL_DECLARED_INLINE_P (code_pattern)
11001 && !DECL_DECLARED_INLINE_P (decl))
11002 DECL_DECLARED_INLINE_P (decl) = 1;
11003 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11004 DECL_INLINE (decl) = 1;
11006 else if (TREE_CODE (decl) == VAR_DECL)
11008 if (!DECL_INITIALIZED_IN_CLASS_P (decl)
11009 && DECL_INITIAL (code_pattern))
11010 DECL_INITIAL (decl) =
11011 tsubst_expr (DECL_INITIAL (code_pattern), args,
11012 tf_error, DECL_TI_TEMPLATE (decl));
11015 gcc_unreachable ();
11017 pop_access_scope (decl);
11020 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11021 substituted to get DECL. */
11024 template_for_substitution (tree decl)
11026 tree tmpl = DECL_TI_TEMPLATE (decl);
11028 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11029 for the instantiation. This is not always the most general
11030 template. Consider, for example:
11033 struct S { template <class U> void f();
11034 template <> void f<int>(); };
11036 and an instantiation of S<double>::f<int>. We want TD to be the
11037 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11038 while (/* An instantiation cannot have a definition, so we need a
11039 more general template. */
11040 DECL_TEMPLATE_INSTANTIATION (tmpl)
11041 /* We must also deal with friend templates. Given:
11043 template <class T> struct S {
11044 template <class U> friend void f() {};
11047 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11048 so far as the language is concerned, but that's still
11049 where we get the pattern for the instantiation from. On
11050 other hand, if the definition comes outside the class, say:
11052 template <class T> struct S {
11053 template <class U> friend void f();
11055 template <class U> friend void f() {}
11057 we don't need to look any further. That's what the check for
11058 DECL_INITIAL is for. */
11059 || (TREE_CODE (decl) == FUNCTION_DECL
11060 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11061 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11063 /* The present template, TD, should not be a definition. If it
11064 were a definition, we should be using it! Note that we
11065 cannot restructure the loop to just keep going until we find
11066 a template with a definition, since that might go too far if
11067 a specialization was declared, but not defined. */
11068 gcc_assert (TREE_CODE (decl) != VAR_DECL
11069 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11071 /* Fetch the more general template. */
11072 tmpl = DECL_TI_TEMPLATE (tmpl);
11078 /* Produce the definition of D, a _DECL generated from a template. If
11079 DEFER_OK is nonzero, then we don't have to actually do the
11080 instantiation now; we just have to do it sometime. Normally it is
11081 an error if this is an explicit instantiation but D is undefined.
11082 If UNDEFINED_OK is nonzero, then instead we treat it as an implicit
11083 instantiation. UNDEFINED_OK is nonzero only if we are being used
11084 to instantiate the members of an explicitly instantiated class
11089 instantiate_decl (tree d, int defer_ok, int undefined_ok)
11091 tree tmpl = DECL_TI_TEMPLATE (d);
11098 int pattern_defined;
11100 location_t saved_loc = input_location;
11102 /* This function should only be used to instantiate templates for
11103 functions and static member variables. */
11104 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11105 || TREE_CODE (d) == VAR_DECL);
11107 /* Variables are never deferred; if instantiation is required, they
11108 are instantiated right away. That allows for better code in the
11109 case that an expression refers to the value of the variable --
11110 if the variable has a constant value the referring expression can
11111 take advantage of that fact. */
11112 if (TREE_CODE (d) == VAR_DECL)
11115 /* Don't instantiate cloned functions. Instead, instantiate the
11116 functions they cloned. */
11117 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11118 d = DECL_CLONED_FUNCTION (d);
11120 if (DECL_TEMPLATE_INSTANTIATED (d))
11121 /* D has already been instantiated. It might seem reasonable to
11122 check whether or not D is an explicit instantiation, and, if so,
11123 stop here. But when an explicit instantiation is deferred
11124 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11125 is set, even though we still need to do the instantiation. */
11128 /* If we already have a specialization of this declaration, then
11129 there's no reason to instantiate it. Note that
11130 retrieve_specialization gives us both instantiations and
11131 specializations, so we must explicitly check
11132 DECL_TEMPLATE_SPECIALIZATION. */
11133 gen_tmpl = most_general_template (tmpl);
11134 gen_args = DECL_TI_ARGS (d);
11135 spec = retrieve_specialization (gen_tmpl, gen_args,
11136 /*class_specializations_p=*/false);
11137 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11140 /* This needs to happen before any tsubsting. */
11141 if (! push_tinst_level (d))
11144 timevar_push (TV_PARSE);
11146 /* We may be in the middle of deferred access check. Disable it now. */
11147 push_deferring_access_checks (dk_no_deferred);
11149 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11150 for the instantiation. */
11151 td = template_for_substitution (d);
11152 code_pattern = DECL_TEMPLATE_RESULT (td);
11154 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11155 || DECL_TEMPLATE_SPECIALIZATION (td))
11156 /* In the case of a friend template whose definition is provided
11157 outside the class, we may have too many arguments. Drop the
11158 ones we don't need. The same is true for specializations. */
11159 args = get_innermost_template_args
11160 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11164 if (TREE_CODE (d) == FUNCTION_DECL)
11165 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11167 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11168 /* Unless an explicit instantiation directive has already determined
11169 the linkage of D, remember that a definition is available for
11171 if (pattern_defined
11172 && !DECL_INTERFACE_KNOWN (d)
11173 && !DECL_NOT_REALLY_EXTERN (d))
11174 mark_definable (d);
11176 input_location = DECL_SOURCE_LOCATION (d);
11178 if (! pattern_defined && DECL_EXPLICIT_INSTANTIATION (d) && undefined_ok)
11180 DECL_NOT_REALLY_EXTERN (d) = 0;
11181 SET_DECL_IMPLICIT_INSTANTIATION (d);
11186 /* Recheck the substitutions to obtain any warning messages
11187 about ignoring cv qualifiers. */
11188 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11189 tree type = TREE_TYPE (gen);
11191 /* Make sure that we can see identifiers, and compute access
11192 correctly. D is already the target FUNCTION_DECL with the
11194 push_access_scope (d);
11196 if (TREE_CODE (gen) == FUNCTION_DECL)
11198 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11199 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11200 tf_error | tf_warning, d);
11201 /* Don't simply tsubst the function type, as that will give
11202 duplicate warnings about poor parameter qualifications.
11203 The function arguments are the same as the decl_arguments
11204 without the top level cv qualifiers. */
11205 type = TREE_TYPE (type);
11207 tsubst (type, gen_args, tf_error | tf_warning, d);
11209 pop_access_scope (d);
11212 /* We should have set up DECL_INITIAL in instantiate_class_template
11213 for in-class definitions of static data members. */
11214 gcc_assert (!(TREE_CODE (d) == VAR_DECL
11215 && DECL_INITIALIZED_IN_CLASS_P (d)
11216 && DECL_INITIAL (d) == NULL_TREE));
11218 /* Do not instantiate templates that we know will be defined
11220 if (DECL_INTERFACE_KNOWN (d)
11221 && DECL_REALLY_EXTERN (d)
11222 && ! (TREE_CODE (d) == FUNCTION_DECL
11223 && DECL_INLINE (d)))
11225 /* Defer all other templates, unless we have been explicitly
11226 forbidden from doing so. We restore the source position here
11227 because it's used by add_pending_template. */
11228 else if (! pattern_defined || defer_ok)
11230 input_location = saved_loc;
11232 if (at_eof && !pattern_defined
11233 && DECL_EXPLICIT_INSTANTIATION (d))
11236 The definition of a non-exported function template, a
11237 non-exported member function template, or a non-exported
11238 member function or static data member of a class template
11239 shall be present in every translation unit in which it is
11240 explicitly instantiated. */
11242 ("explicit instantiation of %qD but no definition available", d);
11244 add_pending_template (d);
11247 /* Tell the repository that D is available in this translation unit
11248 -- and see if it is supposed to be instantiated here. */
11249 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11251 /* In a PCH file, despite the fact that the repository hasn't
11252 requested instantiation in the PCH it is still possible that
11253 an instantiation will be required in a file that includes the
11256 add_pending_template (d);
11257 /* Instantiate inline functions so that the inliner can do its
11258 job, even though we'll not be emitting a copy of this
11260 if (!(TREE_CODE (d) == FUNCTION_DECL
11261 && flag_inline_trees
11262 && DECL_DECLARED_INLINE_P (d)))
11266 need_push = !cfun || !global_bindings_p ();
11268 push_to_top_level ();
11270 /* Mark D as instantiated so that recursive calls to
11271 instantiate_decl do not try to instantiate it again. */
11272 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11274 /* Regenerate the declaration in case the template has been modified
11275 by a subsequent redeclaration. */
11276 regenerate_decl_from_template (d, td);
11278 /* We already set the file and line above. Reset them now in case
11279 they changed as a result of calling regenerate_decl_from_template. */
11280 input_location = DECL_SOURCE_LOCATION (d);
11282 if (TREE_CODE (d) == VAR_DECL)
11284 /* Clear out DECL_RTL; whatever was there before may not be right
11285 since we've reset the type of the declaration. */
11286 SET_DECL_RTL (d, NULL_RTX);
11287 DECL_IN_AGGR_P (d) = 0;
11289 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11290 initializer. That function will defer actual emission until
11291 we have a chance to determine linkage. */
11292 DECL_EXTERNAL (d) = 0;
11294 /* Enter the scope of D so that access-checking works correctly. */
11295 push_nested_class (DECL_CONTEXT (d));
11297 (!DECL_INITIALIZED_IN_CLASS_P (d)
11298 ? DECL_INITIAL (d) : NULL_TREE),
11300 pop_nested_class ();
11302 else if (TREE_CODE (d) == FUNCTION_DECL)
11304 htab_t saved_local_specializations;
11309 /* Save away the current list, in case we are instantiating one
11310 template from within the body of another. */
11311 saved_local_specializations = local_specializations;
11313 /* Set up the list of local specializations. */
11314 local_specializations = htab_create (37,
11315 hash_local_specialization,
11316 eq_local_specializations,
11319 /* Set up context. */
11320 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11322 /* Create substitution entries for the parameters. */
11323 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11324 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11325 spec_parm = DECL_ARGUMENTS (d);
11326 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11328 register_local_specialization (spec_parm, tmpl_parm);
11329 spec_parm = skip_artificial_parms_for (d, spec_parm);
11330 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11334 register_local_specialization (spec_parm, tmpl_parm);
11335 tmpl_parm = TREE_CHAIN (tmpl_parm);
11336 spec_parm = TREE_CHAIN (spec_parm);
11338 gcc_assert (!spec_parm);
11340 /* Substitute into the body of the function. */
11341 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11342 tf_error | tf_warning, tmpl);
11344 /* We don't need the local specializations any more. */
11345 htab_delete (local_specializations);
11346 local_specializations = saved_local_specializations;
11348 /* Finish the function. */
11349 d = finish_function (0);
11350 expand_or_defer_fn (d);
11353 /* We're not deferring instantiation any more. */
11354 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11357 pop_from_top_level ();
11360 input_location = saved_loc;
11361 pop_deferring_access_checks ();
11362 pop_tinst_level ();
11364 timevar_pop (TV_PARSE);
11369 /* Run through the list of templates that we wish we could
11370 instantiate, and instantiate any we can. RETRIES is the
11371 number of times we retry pending template instantiation. */
11374 instantiate_pending_templates (int retries)
11377 tree last = NULL_TREE;
11379 location_t saved_loc = input_location;
11381 /* Instantiating templates may trigger vtable generation. This in turn
11382 may require further template instantiations. We place a limit here
11383 to avoid infinite loop. */
11384 if (pending_templates && retries >= max_tinst_depth)
11386 cp_error_at ("template instantiation depth exceeds maximum of %d"
11387 " (use -ftemplate-depth-NN to increase the maximum)"
11388 " instantiating %q+D, possibly from virtual table"
11390 max_tinst_depth, TREE_VALUE (pending_templates));
11398 t = &pending_templates;
11401 tree instantiation = TREE_VALUE (*t);
11403 reopen_tinst_level (TREE_PURPOSE (*t));
11405 if (TYPE_P (instantiation))
11409 if (!COMPLETE_TYPE_P (instantiation))
11411 instantiate_class_template (instantiation);
11412 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11413 for (fn = TYPE_METHODS (instantiation);
11415 fn = TREE_CHAIN (fn))
11416 if (! DECL_ARTIFICIAL (fn))
11417 instantiate_decl (fn, /*defer_ok=*/0,
11418 /*undefined_ok=*/0);
11419 if (COMPLETE_TYPE_P (instantiation))
11423 if (COMPLETE_TYPE_P (instantiation))
11424 /* If INSTANTIATION has been instantiated, then we don't
11425 need to consider it again in the future. */
11426 *t = TREE_CHAIN (*t);
11430 t = &TREE_CHAIN (*t);
11435 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11436 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11438 instantiation = instantiate_decl (instantiation,
11440 /*undefined_ok=*/0);
11441 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11445 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11446 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11447 /* If INSTANTIATION has been instantiated, then we don't
11448 need to consider it again in the future. */
11449 *t = TREE_CHAIN (*t);
11453 t = &TREE_CHAIN (*t);
11457 current_tinst_level = NULL_TREE;
11459 last_pending_template = last;
11461 while (reconsider);
11463 input_location = saved_loc;
11466 /* Substitute ARGVEC into T, which is a list of initializers for
11467 either base class or a non-static data member. The TREE_PURPOSEs
11468 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11469 instantiate_decl. */
11472 tsubst_initializer_list (tree t, tree argvec)
11474 tree inits = NULL_TREE;
11476 for (; t; t = TREE_CHAIN (t))
11482 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11484 decl = expand_member_init (decl);
11485 if (decl && !DECL_P (decl))
11486 in_base_initializer = 1;
11488 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11492 else if (TREE_CODE (init) == TREE_LIST)
11493 for (val = init; val; val = TREE_CHAIN (val))
11494 TREE_VALUE (val) = convert_from_reference (TREE_VALUE (val));
11495 else if (init != void_type_node)
11496 init = convert_from_reference (init);
11498 in_base_initializer = 0;
11502 init = build_tree_list (decl, init);
11503 TREE_CHAIN (init) = inits;
11510 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11513 set_current_access_from_decl (tree decl)
11515 if (TREE_PRIVATE (decl))
11516 current_access_specifier = access_private_node;
11517 else if (TREE_PROTECTED (decl))
11518 current_access_specifier = access_protected_node;
11520 current_access_specifier = access_public_node;
11523 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11524 is the instantiation (which should have been created with
11525 start_enum) and ARGS are the template arguments to use. */
11528 tsubst_enum (tree tag, tree newtag, tree args)
11532 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11537 decl = TREE_VALUE (e);
11538 /* Note that in a template enum, the TREE_VALUE is the
11539 CONST_DECL, not the corresponding INTEGER_CST. */
11540 value = tsubst_expr (DECL_INITIAL (decl),
11541 args, tf_error | tf_warning,
11544 /* Give this enumeration constant the correct access. */
11545 set_current_access_from_decl (decl);
11547 /* Actually build the enumerator itself. */
11548 build_enumerator (DECL_NAME (decl), value, newtag);
11551 finish_enum (newtag);
11552 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11553 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11556 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11557 its type -- but without substituting the innermost set of template
11558 arguments. So, innermost set of template parameters will appear in
11562 get_mostly_instantiated_function_type (tree decl)
11570 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11571 targs = DECL_TI_ARGS (decl);
11572 tparms = DECL_TEMPLATE_PARMS (tmpl);
11573 parm_depth = TMPL_PARMS_DEPTH (tparms);
11575 /* There should be as many levels of arguments as there are levels
11577 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11579 fn_type = TREE_TYPE (tmpl);
11581 if (parm_depth == 1)
11582 /* No substitution is necessary. */
11589 /* Replace the innermost level of the TARGS with NULL_TREEs to
11590 let tsubst know not to substitute for those parameters. */
11591 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11592 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11593 SET_TMPL_ARGS_LEVEL (partial_args, i,
11594 TMPL_ARGS_LEVEL (targs, i));
11595 SET_TMPL_ARGS_LEVEL (partial_args,
11596 TMPL_ARGS_DEPTH (targs),
11597 make_tree_vec (DECL_NTPARMS (tmpl)));
11599 /* Make sure that we can see identifiers, and compute access
11600 correctly. We can just use the context of DECL for the
11601 partial substitution here. It depends only on outer template
11602 parameters, regardless of whether the innermost level is
11603 specialized or not. */
11604 push_access_scope (decl);
11606 ++processing_template_decl;
11607 /* Now, do the (partial) substitution to figure out the
11608 appropriate function type. */
11609 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11610 --processing_template_decl;
11612 /* Substitute into the template parameters to obtain the real
11613 innermost set of parameters. This step is important if the
11614 innermost set of template parameters contains value
11615 parameters whose types depend on outer template parameters. */
11616 TREE_VEC_LENGTH (partial_args)--;
11617 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11619 pop_access_scope (decl);
11625 /* Return truthvalue if we're processing a template different from
11626 the last one involved in diagnostics. */
11628 problematic_instantiation_changed (void)
11630 return last_template_error_tick != tinst_level_tick;
11633 /* Remember current template involved in diagnostics. */
11635 record_last_problematic_instantiation (void)
11637 last_template_error_tick = tinst_level_tick;
11641 current_instantiation (void)
11643 return current_tinst_level;
11646 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11647 type. Return zero for ok, nonzero for disallowed. Issue error and
11648 warning messages under control of COMPLAIN. */
11651 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11653 if (INTEGRAL_TYPE_P (type))
11655 else if (POINTER_TYPE_P (type))
11657 else if (TYPE_PTR_TO_MEMBER_P (type))
11659 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11661 else if (TREE_CODE (type) == TYPENAME_TYPE)
11664 if (complain & tf_error)
11665 error ("%q#T is not a valid type for a template constant parameter", type);
11669 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11670 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11673 dependent_type_p_r (tree type)
11679 A type is dependent if it is:
11681 -- a template parameter. Template template parameters are types
11682 for us (since TYPE_P holds true for them) so we handle
11684 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11685 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11687 /* -- a qualified-id with a nested-name-specifier which contains a
11688 class-name that names a dependent type or whose unqualified-id
11689 names a dependent type. */
11690 if (TREE_CODE (type) == TYPENAME_TYPE)
11692 /* -- a cv-qualified type where the cv-unqualified type is
11694 type = TYPE_MAIN_VARIANT (type);
11695 /* -- a compound type constructed from any dependent type. */
11696 if (TYPE_PTR_TO_MEMBER_P (type))
11697 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11698 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11700 else if (TREE_CODE (type) == POINTER_TYPE
11701 || TREE_CODE (type) == REFERENCE_TYPE)
11702 return dependent_type_p (TREE_TYPE (type));
11703 else if (TREE_CODE (type) == FUNCTION_TYPE
11704 || TREE_CODE (type) == METHOD_TYPE)
11708 if (dependent_type_p (TREE_TYPE (type)))
11710 for (arg_type = TYPE_ARG_TYPES (type);
11712 arg_type = TREE_CHAIN (arg_type))
11713 if (dependent_type_p (TREE_VALUE (arg_type)))
11717 /* -- an array type constructed from any dependent type or whose
11718 size is specified by a constant expression that is
11719 value-dependent. */
11720 if (TREE_CODE (type) == ARRAY_TYPE)
11722 if (TYPE_DOMAIN (type)
11723 && ((value_dependent_expression_p
11724 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11725 || (type_dependent_expression_p
11726 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11728 return dependent_type_p (TREE_TYPE (type));
11731 /* -- a template-id in which either the template name is a template
11733 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11735 /* ... or any of the template arguments is a dependent type or
11736 an expression that is type-dependent or value-dependent. */
11737 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11738 && (any_dependent_template_arguments_p
11739 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11742 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11743 expression is not type-dependent, then it should already been
11745 if (TREE_CODE (type) == TYPEOF_TYPE)
11748 /* The standard does not specifically mention types that are local
11749 to template functions or local classes, but they should be
11750 considered dependent too. For example:
11752 template <int I> void f() {
11757 The size of `E' cannot be known until the value of `I' has been
11758 determined. Therefore, `E' must be considered dependent. */
11759 scope = TYPE_CONTEXT (type);
11760 if (scope && TYPE_P (scope))
11761 return dependent_type_p (scope);
11762 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11763 return type_dependent_expression_p (scope);
11765 /* Other types are non-dependent. */
11769 /* Returns TRUE if TYPE is dependent, in the sense of
11770 [temp.dep.type]. */
11773 dependent_type_p (tree type)
11775 /* If there are no template parameters in scope, then there can't be
11776 any dependent types. */
11777 if (!processing_template_decl)
11780 /* If the type is NULL, we have not computed a type for the entity
11781 in question; in that case, the type is dependent. */
11785 /* Erroneous types can be considered non-dependent. */
11786 if (type == error_mark_node)
11789 /* If we have not already computed the appropriate value for TYPE,
11791 if (!TYPE_DEPENDENT_P_VALID (type))
11793 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11794 TYPE_DEPENDENT_P_VALID (type) = 1;
11797 return TYPE_DEPENDENT_P (type);
11800 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11803 dependent_scope_ref_p (tree expression, bool criterion (tree))
11808 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
11810 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11813 scope = TREE_OPERAND (expression, 0);
11814 name = TREE_OPERAND (expression, 1);
11818 An id-expression is type-dependent if it contains a
11819 nested-name-specifier that contains a class-name that names a
11821 /* The suggested resolution to Core Issue 2 implies that if the
11822 qualifying type is the current class, then we must peek
11825 && currently_open_class (scope)
11826 && !criterion (name))
11828 if (dependent_type_p (scope))
11834 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11835 [temp.dep.constexpr] */
11838 value_dependent_expression_p (tree expression)
11840 if (!processing_template_decl)
11843 /* A name declared with a dependent type. */
11844 if (TREE_CODE (expression) == IDENTIFIER_NODE
11845 || (DECL_P (expression)
11846 && type_dependent_expression_p (expression)))
11848 /* A non-type template parameter. */
11849 if ((TREE_CODE (expression) == CONST_DECL
11850 && DECL_TEMPLATE_PARM_P (expression))
11851 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11853 /* A constant with integral or enumeration type and is initialized
11854 with an expression that is value-dependent. */
11855 if (TREE_CODE (expression) == VAR_DECL
11856 && DECL_INITIAL (expression)
11857 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11858 && value_dependent_expression_p (DECL_INITIAL (expression)))
11860 /* These expressions are value-dependent if the type to which the
11861 cast occurs is dependent or the expression being casted is
11862 value-dependent. */
11863 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11864 || TREE_CODE (expression) == STATIC_CAST_EXPR
11865 || TREE_CODE (expression) == CONST_CAST_EXPR
11866 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11867 || TREE_CODE (expression) == CAST_EXPR)
11869 tree type = TREE_TYPE (expression);
11870 if (dependent_type_p (type))
11872 /* A functional cast has a list of operands. */
11873 expression = TREE_OPERAND (expression, 0);
11876 /* If there are no operands, it must be an expression such
11877 as "int()". This should not happen for aggregate types
11878 because it would form non-constant expressions. */
11879 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
11883 if (TREE_CODE (expression) == TREE_LIST)
11887 if (value_dependent_expression_p (TREE_VALUE (expression)))
11889 expression = TREE_CHAIN (expression);
11891 while (expression);
11895 return value_dependent_expression_p (expression);
11897 /* A `sizeof' expression is value-dependent if the operand is
11899 if (TREE_CODE (expression) == SIZEOF_EXPR
11900 || TREE_CODE (expression) == ALIGNOF_EXPR)
11902 expression = TREE_OPERAND (expression, 0);
11903 if (TYPE_P (expression))
11904 return dependent_type_p (expression);
11905 return type_dependent_expression_p (expression);
11907 if (TREE_CODE (expression) == SCOPE_REF)
11908 return dependent_scope_ref_p (expression, value_dependent_expression_p);
11909 if (TREE_CODE (expression) == COMPONENT_REF)
11910 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
11911 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
11912 /* A constant expression is value-dependent if any subexpression is
11913 value-dependent. */
11914 if (EXPR_P (expression))
11916 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
11919 return (value_dependent_expression_p
11920 (TREE_OPERAND (expression, 0)));
11921 case tcc_comparison:
11923 return ((value_dependent_expression_p
11924 (TREE_OPERAND (expression, 0)))
11925 || (value_dependent_expression_p
11926 (TREE_OPERAND (expression, 1))));
11927 case tcc_expression:
11930 for (i = 0; i < first_rtl_op (TREE_CODE (expression)); ++i)
11931 /* In some cases, some of the operands may be missing.
11932 (For example, in the case of PREDECREMENT_EXPR, the
11933 amount to increment by may be missing.) That doesn't
11934 make the expression dependent. */
11935 if (TREE_OPERAND (expression, i)
11936 && (value_dependent_expression_p
11937 (TREE_OPERAND (expression, i))))
11941 case tcc_reference:
11942 case tcc_statement:
11943 /* These cannot be value dependent. */
11947 gcc_unreachable ();
11951 /* The expression is not value-dependent. */
11955 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11956 [temp.dep.expr]. */
11959 type_dependent_expression_p (tree expression)
11961 if (!processing_template_decl)
11964 if (expression == error_mark_node)
11967 /* An unresolved name is always dependent. */
11968 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11971 /* Some expression forms are never type-dependent. */
11972 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
11973 || TREE_CODE (expression) == SIZEOF_EXPR
11974 || TREE_CODE (expression) == ALIGNOF_EXPR
11975 || TREE_CODE (expression) == TYPEID_EXPR
11976 || TREE_CODE (expression) == DELETE_EXPR
11977 || TREE_CODE (expression) == VEC_DELETE_EXPR
11978 || TREE_CODE (expression) == THROW_EXPR)
11981 /* The types of these expressions depends only on the type to which
11982 the cast occurs. */
11983 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11984 || TREE_CODE (expression) == STATIC_CAST_EXPR
11985 || TREE_CODE (expression) == CONST_CAST_EXPR
11986 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11987 || TREE_CODE (expression) == CAST_EXPR)
11988 return dependent_type_p (TREE_TYPE (expression));
11990 /* The types of these expressions depends only on the type created
11991 by the expression. */
11992 if (TREE_CODE (expression) == NEW_EXPR
11993 || TREE_CODE (expression) == VEC_NEW_EXPR)
11995 /* For NEW_EXPR tree nodes created inside a template, either
11996 the object type itself or a TREE_LIST may appear as the
11998 tree type = TREE_OPERAND (expression, 1);
11999 if (TREE_CODE (type) == TREE_LIST)
12000 /* This is an array type. We need to check array dimensions
12002 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12003 || value_dependent_expression_p
12004 (TREE_OPERAND (TREE_VALUE (type), 1));
12006 return dependent_type_p (type);
12009 if (TREE_CODE (expression) == SCOPE_REF
12010 && dependent_scope_ref_p (expression,
12011 type_dependent_expression_p))
12014 if (TREE_CODE (expression) == FUNCTION_DECL
12015 && DECL_LANG_SPECIFIC (expression)
12016 && DECL_TEMPLATE_INFO (expression)
12017 && (any_dependent_template_arguments_p
12018 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12021 if (TREE_CODE (expression) == TEMPLATE_DECL
12022 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12025 if (TREE_TYPE (expression) == unknown_type_node)
12027 if (TREE_CODE (expression) == ADDR_EXPR)
12028 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12029 if (TREE_CODE (expression) == COMPONENT_REF
12030 || TREE_CODE (expression) == OFFSET_REF)
12032 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12034 expression = TREE_OPERAND (expression, 1);
12035 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12038 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12039 if (TREE_CODE (expression) == SCOPE_REF)
12042 if (TREE_CODE (expression) == BASELINK)
12043 expression = BASELINK_FUNCTIONS (expression);
12045 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12047 if (any_dependent_template_arguments_p
12048 (TREE_OPERAND (expression, 1)))
12050 expression = TREE_OPERAND (expression, 0);
12052 gcc_assert (TREE_CODE (expression) == OVERLOAD);
12056 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12058 expression = OVL_NEXT (expression);
12063 return (dependent_type_p (TREE_TYPE (expression)));
12066 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12067 contains a type-dependent expression. */
12070 any_type_dependent_arguments_p (tree args)
12074 tree arg = TREE_VALUE (args);
12076 if (type_dependent_expression_p (arg))
12078 args = TREE_CHAIN (args);
12083 /* Returns TRUE if the ARG (a template argument) is dependent. */
12086 dependent_template_arg_p (tree arg)
12088 if (!processing_template_decl)
12091 if (TREE_CODE (arg) == TEMPLATE_DECL
12092 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12093 return dependent_template_p (arg);
12094 else if (TYPE_P (arg))
12095 return dependent_type_p (arg);
12097 return (type_dependent_expression_p (arg)
12098 || value_dependent_expression_p (arg));
12101 /* Returns true if ARGS (a collection of template arguments) contains
12102 any dependent arguments. */
12105 any_dependent_template_arguments_p (tree args)
12113 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12115 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12116 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12117 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12124 /* Returns TRUE if the template TMPL is dependent. */
12127 dependent_template_p (tree tmpl)
12129 if (TREE_CODE (tmpl) == OVERLOAD)
12133 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12135 tmpl = OVL_CHAIN (tmpl);
12140 /* Template template parameters are dependent. */
12141 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12142 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12144 /* So are names that have not been looked up. */
12145 if (TREE_CODE (tmpl) == SCOPE_REF
12146 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12148 /* So are member templates of dependent classes. */
12149 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12150 return dependent_type_p (DECL_CONTEXT (tmpl));
12154 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12157 dependent_template_id_p (tree tmpl, tree args)
12159 return (dependent_template_p (tmpl)
12160 || any_dependent_template_arguments_p (args));
12163 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12164 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12165 can be found. Note that this function peers inside uninstantiated
12166 templates and therefore should be used only in extremely limited
12170 resolve_typename_type (tree type, bool only_current_p)
12178 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12180 scope = TYPE_CONTEXT (type);
12181 name = TYPE_IDENTIFIER (type);
12183 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12184 it first before we can figure out what NAME refers to. */
12185 if (TREE_CODE (scope) == TYPENAME_TYPE)
12186 scope = resolve_typename_type (scope, only_current_p);
12187 /* If we don't know what SCOPE refers to, then we cannot resolve the
12189 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12190 return error_mark_node;
12191 /* If the SCOPE is a template type parameter, we have no way of
12192 resolving the name. */
12193 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12195 /* If the SCOPE is not the current instantiation, there's no reason
12196 to look inside it. */
12197 if (only_current_p && !currently_open_class (scope))
12198 return error_mark_node;
12199 /* If SCOPE is a partial instantiation, it will not have a valid
12200 TYPE_FIELDS list, so use the original template. */
12201 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12202 /* Enter the SCOPE so that name lookup will be resolved as if we
12203 were in the class definition. In particular, SCOPE will no
12204 longer be considered a dependent type. */
12205 pop_p = push_scope (scope);
12206 /* Look up the declaration. */
12207 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12208 /* Obtain the set of qualifiers applied to the TYPE. */
12209 quals = cp_type_quals (type);
12210 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12211 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12213 type = error_mark_node;
12214 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12215 && TREE_CODE (decl) == TYPE_DECL)
12216 type = TREE_TYPE (decl);
12217 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12218 && DECL_CLASS_TEMPLATE_P (decl))
12222 /* Obtain the template and the arguments. */
12223 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12224 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12225 /* Instantiate the template. */
12226 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12227 /*entering_scope=*/0, tf_error | tf_user);
12230 type = error_mark_node;
12231 /* Qualify the resulting type. */
12232 if (type != error_mark_node && quals)
12233 type = cp_build_qualified_type (type, quals);
12234 /* Leave the SCOPE. */
12241 /* EXPR is an expression which is not type-dependent. Return a proxy
12242 for EXPR that can be used to compute the types of larger
12243 expressions containing EXPR. */
12246 build_non_dependent_expr (tree expr)
12250 /* Preserve null pointer constants so that the type of things like
12251 "p == 0" where "p" is a pointer can be determined. */
12252 if (null_ptr_cst_p (expr))
12254 /* Preserve OVERLOADs; the functions must be available to resolve
12256 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12257 TREE_OPERAND (expr, 0) : expr);
12258 if (TREE_CODE (inner_expr) == OVERLOAD
12259 || TREE_CODE (inner_expr) == FUNCTION_DECL
12260 || TREE_CODE (inner_expr) == TEMPLATE_DECL
12261 || TREE_CODE (inner_expr) == TEMPLATE_ID_EXPR)
12263 /* Preserve string constants; conversions from string constants to
12264 "char *" are allowed, even though normally a "const char *"
12265 cannot be used to initialize a "char *". */
12266 if (TREE_CODE (expr) == STRING_CST)
12268 /* Preserve arithmetic constants, as an optimization -- there is no
12269 reason to create a new node. */
12270 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12272 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12273 There is at least one place where we want to know that a
12274 particular expression is a throw-expression: when checking a ?:
12275 expression, there are special rules if the second or third
12276 argument is a throw-expression. */
12277 if (TREE_CODE (expr) == THROW_EXPR)
12280 if (TREE_CODE (expr) == COND_EXPR)
12281 return build3 (COND_EXPR,
12283 TREE_OPERAND (expr, 0),
12284 (TREE_OPERAND (expr, 1)
12285 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12286 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12287 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12288 if (TREE_CODE (expr) == COMPOUND_EXPR
12289 && !COMPOUND_EXPR_OVERLOADED (expr))
12290 return build2 (COMPOUND_EXPR,
12292 TREE_OPERAND (expr, 0),
12293 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12295 /* Otherwise, build a NON_DEPENDENT_EXPR.
12297 REFERENCE_TYPEs are not stripped for expressions in templates
12298 because doing so would play havoc with mangling. Consider, for
12301 template <typename T> void f<T& g>() { g(); }
12303 In the body of "f", the expression for "g" will have
12304 REFERENCE_TYPE, even though the standard says that it should
12305 not. The reason is that we must preserve the syntactic form of
12306 the expression so that mangling (say) "f<g>" inside the body of
12307 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12309 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12312 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12313 Return a new TREE_LIST with the various arguments replaced with
12314 equivalent non-dependent expressions. */
12317 build_non_dependent_args (tree args)
12322 new_args = NULL_TREE;
12323 for (a = args; a; a = TREE_CHAIN (a))
12324 new_args = tree_cons (NULL_TREE,
12325 build_non_dependent_expr (TREE_VALUE (a)),
12327 return nreverse (new_args);
12330 #include "gt-cp-pt.h"