1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
37 #include "tree-inline.h"
46 /* The type of functions taking a tree, and some additional data, and
48 typedef int (*tree_fn_t) (tree, void*);
50 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
51 instantiations have been deferred, either because their definitions
52 were not yet available, or because we were putting off doing the work.
53 The TREE_PURPOSE of each entry is either a DECL (for a function or
54 static data member), or a TYPE (for a class) indicating what we are
55 hoping to instantiate. The TREE_VALUE is not used. */
56 static GTY(()) tree pending_templates;
57 static GTY(()) tree last_pending_template;
59 int processing_template_parmlist;
60 static int template_header_count;
62 static GTY(()) tree saved_trees;
63 static GTY(()) varray_type inline_parm_levels;
64 static size_t inline_parm_levels_used;
66 static GTY(()) tree current_tinst_level;
68 static GTY(()) tree saved_access_scope;
70 /* A map from local variable declarations in the body of the template
71 presently being instantiated to the corresponding instantiated
73 static htab_t local_specializations;
75 #define UNIFY_ALLOW_NONE 0
76 #define UNIFY_ALLOW_MORE_CV_QUAL 1
77 #define UNIFY_ALLOW_LESS_CV_QUAL 2
78 #define UNIFY_ALLOW_DERIVED 4
79 #define UNIFY_ALLOW_INTEGER 8
80 #define UNIFY_ALLOW_OUTER_LEVEL 16
81 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
82 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
83 #define UNIFY_ALLOW_MAX_CORRECTION 128
85 #define GTB_VIA_VIRTUAL 1 /* The base class we are examining is
86 virtual, or a base class of a virtual
88 #define GTB_IGNORE_TYPE 2 /* We don't need to try to unify the current
89 type with the desired type. */
91 static void push_access_scope (tree);
92 static void pop_access_scope (tree);
93 static int resolve_overloaded_unification (tree, tree, tree, tree,
94 unification_kind_t, int);
95 static int try_one_overload (tree, tree, tree, tree, tree,
96 unification_kind_t, int);
97 static int unify (tree, tree, tree, tree, int);
98 static void add_pending_template (tree);
99 static void reopen_tinst_level (tree);
100 static tree classtype_mangled_name (tree);
101 static char* mangle_class_name_for_template (const char *, tree, tree);
102 static tree tsubst_initializer_list (tree, tree);
103 static int list_eq (tree, tree);
104 static tree get_class_bindings (tree, tree, tree);
105 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
106 static void tsubst_enum (tree, tree, tree);
107 static tree add_to_template_args (tree, tree);
108 static tree add_outermost_template_args (tree, tree);
109 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
110 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
111 static int type_unification_real (tree, tree, tree, tree,
112 int, unification_kind_t, int, int);
113 static void note_template_header (int);
114 static tree maybe_fold_nontype_arg (tree);
115 static void maybe_fold_nontype_args (tree);
116 static tree convert_nontype_argument (tree, tree);
117 static tree convert_template_argument (tree, tree, tree,
118 tsubst_flags_t, int, tree);
119 static tree get_bindings_overload (tree, tree, tree);
120 static int for_each_template_parm (tree, tree_fn_t, void*, htab_t);
121 static tree build_template_parm_index (int, int, int, tree, tree);
122 static int inline_needs_template_parms (tree);
123 static void push_inline_template_parms_recursive (tree, int);
124 static tree retrieve_specialization (tree, tree);
125 static tree retrieve_local_specialization (tree);
126 static tree register_specialization (tree, tree, tree);
127 static void register_local_specialization (tree, tree);
128 static tree reduce_template_parm_level (tree, tree, int);
129 static tree build_template_decl (tree, tree);
130 static int mark_template_parm (tree, void *);
131 static int template_parm_this_level_p (tree, void *);
132 static tree tsubst_friend_function (tree, tree);
133 static tree tsubst_friend_class (tree, tree);
134 static int can_complete_type_without_circularity (tree);
135 static tree get_bindings_real (tree, tree, tree, int, int, int);
136 static int template_decl_level (tree);
137 static int check_cv_quals_for_unify (int, tree, tree);
138 static tree tsubst_template_arg_vector (tree, tree, tsubst_flags_t);
139 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
140 static void regenerate_decl_from_template (tree, tree);
141 static tree most_specialized (tree, tree, tree);
142 static tree most_specialized_class (tree, tree);
143 static int template_class_depth_real (tree, int);
144 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
145 static tree tsubst_decl (tree, tree, tree, tsubst_flags_t);
146 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
147 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
148 static void check_specialization_scope (void);
149 static tree process_partial_specialization (tree);
150 static void set_current_access_from_decl (tree);
151 static void check_default_tmpl_args (tree, tree, int, int);
152 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
153 static tree get_template_base_recursive (tree, tree, tree, tree, tree, int);
154 static tree get_template_base (tree, tree, tree, tree);
155 static int verify_class_unification (tree, tree, tree);
156 static tree try_class_unification (tree, tree, tree, tree);
157 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
159 static tree determine_specialization (tree, tree, tree *, int);
160 static int template_args_equal (tree, tree);
161 static void tsubst_default_arguments (tree);
162 static tree for_each_template_parm_r (tree *, int *, void *);
163 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
164 static void copy_default_args_to_explicit_spec (tree);
165 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
166 static int eq_local_specializations (const void *, const void *);
167 static bool dependent_type_p_r (tree);
168 static tree tsubst (tree, tree, tsubst_flags_t, tree);
169 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
170 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
172 /* Make the current scope suitable for access checking when we are
173 processing T. T can be FUNCTION_DECL for instantiated function
174 template, or VAR_DECL for static member variable (need by
175 instantiate_decl). */
178 push_access_scope (tree t)
180 my_friendly_assert (TREE_CODE (t) == FUNCTION_DECL
181 || TREE_CODE (t) == VAR_DECL,
184 if (DECL_CLASS_SCOPE_P (t))
185 push_nested_class (DECL_CONTEXT (t));
187 push_to_top_level ();
189 if (TREE_CODE (t) == FUNCTION_DECL)
191 saved_access_scope = tree_cons
192 (NULL_TREE, current_function_decl, saved_access_scope);
193 current_function_decl = t;
197 /* Restore the scope set up by push_access_scope. T is the node we
201 pop_access_scope (tree t)
203 if (TREE_CODE (t) == FUNCTION_DECL)
205 current_function_decl = TREE_VALUE (saved_access_scope);
206 saved_access_scope = TREE_CHAIN (saved_access_scope);
209 if (DECL_CLASS_SCOPE_P (t))
212 pop_from_top_level ();
215 /* Do any processing required when DECL (a member template
216 declaration) is finished. Returns the TEMPLATE_DECL corresponding
217 to DECL, unless it is a specialization, in which case the DECL
218 itself is returned. */
221 finish_member_template_decl (tree decl)
223 if (decl == error_mark_node)
224 return error_mark_node;
226 my_friendly_assert (DECL_P (decl), 20020812);
228 if (TREE_CODE (decl) == TYPE_DECL)
232 type = TREE_TYPE (decl);
233 if (IS_AGGR_TYPE (type)
234 && CLASSTYPE_TEMPLATE_INFO (type)
235 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
237 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
238 check_member_template (tmpl);
243 else if (TREE_CODE (decl) == FIELD_DECL)
244 error ("data member `%D' cannot be a member template", decl);
245 else if (DECL_TEMPLATE_INFO (decl))
247 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
249 check_member_template (DECL_TI_TEMPLATE (decl));
250 return DECL_TI_TEMPLATE (decl);
256 error ("invalid member template declaration `%D'", decl);
258 return error_mark_node;
261 /* Returns the template nesting level of the indicated class TYPE.
271 A<T>::B<U> has depth two, while A<T> has depth one.
272 Both A<T>::B<int> and A<int>::B<U> have depth one, if
273 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
276 This function is guaranteed to return 0 if passed NULL_TREE so
277 that, for example, `template_class_depth (current_class_type)' is
281 template_class_depth_real (tree type, int count_specializations)
286 type && TREE_CODE (type) != NAMESPACE_DECL;
287 type = (TREE_CODE (type) == FUNCTION_DECL)
288 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
290 if (TREE_CODE (type) != FUNCTION_DECL)
292 if (CLASSTYPE_TEMPLATE_INFO (type)
293 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
294 && ((count_specializations
295 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
296 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
301 if (DECL_TEMPLATE_INFO (type)
302 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
303 && ((count_specializations
304 && DECL_TEMPLATE_SPECIALIZATION (type))
305 || uses_template_parms (DECL_TI_ARGS (type))))
313 /* Returns the template nesting level of the indicated class TYPE.
314 Like template_class_depth_real, but instantiations do not count in
318 template_class_depth (tree type)
320 return template_class_depth_real (type, /*count_specializations=*/0);
323 /* Returns 1 if processing DECL as part of do_pending_inlines
324 needs us to push template parms. */
327 inline_needs_template_parms (tree decl)
329 if (! DECL_TEMPLATE_INFO (decl))
332 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
333 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
336 /* Subroutine of maybe_begin_member_template_processing.
337 Push the template parms in PARMS, starting from LEVELS steps into the
338 chain, and ending at the beginning, since template parms are listed
342 push_inline_template_parms_recursive (tree parmlist, int levels)
344 tree parms = TREE_VALUE (parmlist);
348 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
350 ++processing_template_decl;
351 current_template_parms
352 = tree_cons (size_int (processing_template_decl),
353 parms, current_template_parms);
354 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
357 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
359 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
360 my_friendly_assert (DECL_P (parm), 0);
362 switch (TREE_CODE (parm))
371 /* Make a CONST_DECL as is done in process_template_parm.
372 It is ugly that we recreate this here; the original
373 version built in process_template_parm is no longer
375 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
377 DECL_ARTIFICIAL (decl) = 1;
378 TREE_CONSTANT (decl) = TREE_READONLY (decl) = 1;
379 DECL_INITIAL (decl) = DECL_INITIAL (parm);
380 SET_DECL_TEMPLATE_PARM_P (decl);
391 /* Restore the template parameter context for a member template or
392 a friend template defined in a class definition. */
395 maybe_begin_member_template_processing (tree decl)
400 if (inline_needs_template_parms (decl))
402 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
403 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
405 if (DECL_TEMPLATE_SPECIALIZATION (decl))
408 parms = TREE_CHAIN (parms);
411 push_inline_template_parms_recursive (parms, levels);
414 /* Remember how many levels of template parameters we pushed so that
415 we can pop them later. */
416 if (!inline_parm_levels)
417 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
418 if (inline_parm_levels_used == inline_parm_levels->num_elements)
419 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
420 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
421 ++inline_parm_levels_used;
424 /* Undo the effects of begin_member_template_processing. */
427 maybe_end_member_template_processing (void)
431 if (!inline_parm_levels_used)
434 --inline_parm_levels_used;
436 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
439 --processing_template_decl;
440 current_template_parms = TREE_CHAIN (current_template_parms);
445 /* Returns nonzero iff T is a member template function. We must be
448 template <class T> class C { void f(); }
450 Here, f is a template function, and a member, but not a member
451 template. This function does not concern itself with the origin of
452 T, only its present state. So if we have
454 template <class T> class C { template <class U> void f(U); }
456 then neither C<int>::f<char> nor C<T>::f<double> is considered
457 to be a member template. But, `template <class U> void
458 C<int>::f(U)' is considered a member template. */
461 is_member_template (tree t)
463 if (!DECL_FUNCTION_TEMPLATE_P (t))
464 /* Anything that isn't a function or a template function is
465 certainly not a member template. */
468 /* A local class can't have member templates. */
469 if (decl_function_context (t))
472 return (DECL_FUNCTION_MEMBER_P (DECL_TEMPLATE_RESULT (t))
473 /* If there are more levels of template parameters than
474 there are template classes surrounding the declaration,
475 then we have a member template. */
476 && (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
477 template_class_depth (DECL_CONTEXT (t))));
481 /* Returns nonzero iff T is a member template class. See
482 is_member_template for a description of what precisely constitutes
483 a member template. */
486 is_member_template_class (tree t)
488 if (!DECL_CLASS_TEMPLATE_P (t))
489 /* Anything that isn't a class template, is certainly not a member
493 if (!DECL_CLASS_SCOPE_P (t))
494 /* Anything whose context isn't a class type is surely not a
498 /* If there are more levels of template parameters than there are
499 template classes surrounding the declaration, then we have a
501 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
502 template_class_depth (DECL_CONTEXT (t)));
506 /* Return a new template argument vector which contains all of ARGS,
507 but has as its innermost set of arguments the EXTRA_ARGS. */
510 add_to_template_args (tree args, tree extra_args)
517 extra_depth = TMPL_ARGS_DEPTH (extra_args);
518 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
520 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
521 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
523 for (j = 1; j <= extra_depth; ++j, ++i)
524 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
529 /* Like add_to_template_args, but only the outermost ARGS are added to
530 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
531 (EXTRA_ARGS) levels are added. This function is used to combine
532 the template arguments from a partial instantiation with the
533 template arguments used to attain the full instantiation from the
534 partial instantiation. */
537 add_outermost_template_args (tree args, tree extra_args)
541 /* If there are more levels of EXTRA_ARGS than there are ARGS,
542 something very fishy is going on. */
543 my_friendly_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args),
546 /* If *all* the new arguments will be the EXTRA_ARGS, just return
548 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
551 /* For the moment, we make ARGS look like it contains fewer levels. */
552 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
554 new_args = add_to_template_args (args, extra_args);
556 /* Now, we restore ARGS to its full dimensions. */
557 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
562 /* Return the N levels of innermost template arguments from the ARGS. */
565 get_innermost_template_args (tree args, int n)
571 my_friendly_assert (n >= 0, 20000603);
573 /* If N is 1, just return the innermost set of template arguments. */
575 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
577 /* If we're not removing anything, just return the arguments we were
579 extra_levels = TMPL_ARGS_DEPTH (args) - n;
580 my_friendly_assert (extra_levels >= 0, 20000603);
581 if (extra_levels == 0)
584 /* Make a new set of arguments, not containing the outer arguments. */
585 new_args = make_tree_vec (n);
586 for (i = 1; i <= n; ++i)
587 SET_TMPL_ARGS_LEVEL (new_args, i,
588 TMPL_ARGS_LEVEL (args, i + extra_levels));
593 /* We've got a template header coming up; push to a new level for storing
597 begin_template_parm_list (void)
599 /* We use a non-tag-transparent scope here, which causes pushtag to
600 put tags in this scope, rather than in the enclosing class or
601 namespace scope. This is the right thing, since we want
602 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
603 global template class, push_template_decl handles putting the
604 TEMPLATE_DECL into top-level scope. For a nested template class,
607 template <class T> struct S1 {
608 template <class T> struct S2 {};
611 pushtag contains special code to call pushdecl_with_scope on the
612 TEMPLATE_DECL for S2. */
613 begin_scope (sk_template_parms);
614 ++processing_template_decl;
615 ++processing_template_parmlist;
616 note_template_header (0);
619 /* This routine is called when a specialization is declared. If it is
620 invalid to declare a specialization here, an error is reported. */
623 check_specialization_scope (void)
625 tree scope = current_scope ();
629 An explicit specialization shall be declared in the namespace of
630 which the template is a member, or, for member templates, in the
631 namespace of which the enclosing class or enclosing class
632 template is a member. An explicit specialization of a member
633 function, member class or static data member of a class template
634 shall be declared in the namespace of which the class template
636 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
637 error ("explicit specialization in non-namespace scope `%D'",
642 In an explicit specialization declaration for a member of a class
643 template or a member template that appears in namespace scope,
644 the member template and some of its enclosing class templates may
645 remain unspecialized, except that the declaration shall not
646 explicitly specialize a class member template if its enclosing
647 class templates are not explicitly specialized as well. */
648 if (current_template_parms)
649 error ("enclosing class templates are not explicitly specialized");
652 /* We've just seen template <>. */
655 begin_specialization (void)
657 begin_scope (sk_template_spec);
658 note_template_header (1);
659 check_specialization_scope ();
662 /* Called at then end of processing a declaration preceded by
666 end_specialization (void)
669 reset_specialization ();
672 /* Any template <>'s that we have seen thus far are not referring to a
673 function specialization. */
676 reset_specialization (void)
678 processing_specialization = 0;
679 template_header_count = 0;
682 /* We've just seen a template header. If SPECIALIZATION is nonzero,
683 it was of the form template <>. */
686 note_template_header (int specialization)
688 processing_specialization = specialization;
689 template_header_count++;
692 /* We're beginning an explicit instantiation. */
695 begin_explicit_instantiation (void)
697 my_friendly_assert (!processing_explicit_instantiation, 20020913);
698 processing_explicit_instantiation = true;
703 end_explicit_instantiation (void)
705 my_friendly_assert(processing_explicit_instantiation, 20020913);
706 processing_explicit_instantiation = false;
709 /* The TYPE is being declared. If it is a template type, that means it
710 is a partial specialization. Do appropriate error-checking. */
713 maybe_process_partial_specialization (tree type)
715 /* TYPE maybe an ERROR_MARK_NODE. */
716 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
718 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
720 /* This is for ordinary explicit specialization and partial
721 specialization of a template class such as:
723 template <> class C<int>;
727 template <class T> class C<T*>;
729 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
731 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
732 && !COMPLETE_TYPE_P (type))
734 if (current_namespace
735 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
737 pedwarn ("specializing `%#T' in different namespace", type);
738 cp_pedwarn_at (" from definition of `%#D'",
739 CLASSTYPE_TI_TEMPLATE (type));
741 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
742 if (processing_template_decl)
743 push_template_decl (TYPE_MAIN_DECL (type));
745 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
746 error ("specialization of `%T' after instantiation", type);
748 else if (CLASS_TYPE_P (type)
749 && !CLASSTYPE_USE_TEMPLATE (type)
750 && CLASSTYPE_TEMPLATE_INFO (type)
751 && context && CLASS_TYPE_P (context)
752 && CLASSTYPE_TEMPLATE_INFO (context))
754 /* This is for an explicit specialization of member class
755 template according to [temp.expl.spec/18]:
757 template <> template <class U> class C<int>::D;
759 The context `C<int>' must be an implicit instantiation.
760 Otherwise this is just a member class template declared
763 template <> class C<int> { template <class U> class D; };
764 template <> template <class U> class C<int>::D;
766 In the first case, `C<int>::D' is a specialization of `C<T>::D'
767 while in the second case, `C<int>::D' is a primary template
768 and `C<T>::D' may not exist. */
770 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
771 && !COMPLETE_TYPE_P (type))
775 if (current_namespace
776 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
778 pedwarn ("specializing `%#T' in different namespace", type);
779 cp_pedwarn_at (" from definition of `%#D'",
780 CLASSTYPE_TI_TEMPLATE (type));
783 /* Check for invalid specialization after instantiation:
785 template <> template <> class C<int>::D<int>;
786 template <> template <class U> class C<int>::D; */
788 for (t = DECL_TEMPLATE_INSTANTIATIONS
789 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
790 t; t = TREE_CHAIN (t))
791 if (TREE_VALUE (t) != type
792 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
793 error ("specialization `%T' after instantiation `%T'",
794 type, TREE_VALUE (t));
796 /* Mark TYPE as a specialization. And as a result, we only
797 have one level of template argument for the innermost
799 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
800 CLASSTYPE_TI_ARGS (type)
801 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
804 else if (processing_specialization)
805 error ("explicit specialization of non-template `%T'", type);
808 /* Retrieve the specialization (in the sense of [temp.spec] - a
809 specialization is either an instantiation or an explicit
810 specialization) of TMPL for the given template ARGS. If there is
811 no such specialization, return NULL_TREE. The ARGS are a vector of
812 arguments, or a vector of vectors of arguments, in the case of
813 templates with more than one level of parameters. */
816 retrieve_specialization (tree tmpl, tree args)
820 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
822 /* There should be as many levels of arguments as there are
823 levels of parameters. */
824 my_friendly_assert (TMPL_ARGS_DEPTH (args)
825 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
828 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
831 if (comp_template_args (TREE_PURPOSE (s), args))
832 return TREE_VALUE (s);
837 /* Like retrieve_specialization, but for local declarations. */
840 retrieve_local_specialization (tree tmpl)
843 (tree) htab_find_with_hash (local_specializations, tmpl,
844 htab_hash_pointer (tmpl));
845 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
848 /* Returns nonzero iff DECL is a specialization of TMPL. */
851 is_specialization_of (tree decl, tree tmpl)
855 if (TREE_CODE (decl) == FUNCTION_DECL)
859 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
865 my_friendly_assert (TREE_CODE (decl) == TYPE_DECL, 0);
867 for (t = TREE_TYPE (decl);
869 t = CLASSTYPE_USE_TEMPLATE (t)
870 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
871 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
878 /* Register the specialization SPEC as a specialization of TMPL with
879 the indicated ARGS. Returns SPEC, or an equivalent prior
880 declaration, if available. */
883 register_specialization (tree spec, tree tmpl, tree args)
887 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
889 if (TREE_CODE (spec) == FUNCTION_DECL
890 && uses_template_parms (DECL_TI_ARGS (spec)))
891 /* This is the FUNCTION_DECL for a partial instantiation. Don't
892 register it; we want the corresponding TEMPLATE_DECL instead.
893 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
894 the more obvious `uses_template_parms (spec)' to avoid problems
895 with default function arguments. In particular, given
898 template <class T> void f(T t1, T t = T())
900 the default argument expression is not substituted for in an
901 instantiation unless and until it is actually needed. */
904 /* There should be as many levels of arguments as there are
905 levels of parameters. */
906 my_friendly_assert (TMPL_ARGS_DEPTH (args)
907 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
910 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
914 tree fn = TREE_VALUE (s);
916 /* We can sometimes try to re-register a specialization that we've
917 already got. In particular, regenerate_decl_from_template
918 calls duplicate_decls which will update the specialization
919 list. But, we'll still get called again here anyhow. It's
920 more convenient to simply allow this than to try to prevent it. */
923 else if (comp_template_args (TREE_PURPOSE (s), args))
925 if (DECL_TEMPLATE_SPECIALIZATION (spec))
927 if (DECL_TEMPLATE_INSTANTIATION (fn))
930 || DECL_EXPLICIT_INSTANTIATION (fn))
932 error ("specialization of %D after instantiation",
938 /* This situation should occur only if the first
939 specialization is an implicit instantiation,
940 the second is an explicit specialization, and
941 the implicit instantiation has not yet been
942 used. That situation can occur if we have
943 implicitly instantiated a member function and
944 then specialized it later.
946 We can also wind up here if a friend
947 declaration that looked like an instantiation
948 turns out to be a specialization:
950 template <class T> void foo(T);
951 class S { friend void foo<>(int) };
952 template <> void foo(int);
954 We transform the existing DECL in place so that
955 any pointers to it become pointers to the
958 If there was a definition for the template, but
959 not for the specialization, we want this to
960 look as if there is no definition, and vice
962 DECL_INITIAL (fn) = NULL_TREE;
963 duplicate_decls (spec, fn);
968 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
970 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
971 /* Dup decl failed, but this is a new
972 definition. Set the line number so any errors
973 match this new definition. */
974 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
982 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
983 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
988 /* Unregister the specialization SPEC as a specialization of TMPL.
989 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
990 if the SPEC was listed as a specialization of TMPL. */
993 reregister_specialization (tree spec, tree tmpl, tree new_spec)
997 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
999 s = &TREE_CHAIN (*s))
1000 if (TREE_VALUE (*s) == spec)
1003 *s = TREE_CHAIN (*s);
1005 TREE_VALUE (*s) == new_spec;
1012 /* Compare an entry in the local specializations hash table P1 (which
1013 is really a pointer to a TREE_LIST) with P2 (which is really a
1017 eq_local_specializations (const void *p1, const void *p2)
1019 return TREE_VALUE ((tree) p1) == (tree) p2;
1022 /* Hash P1, an entry in the local specializations table. */
1025 hash_local_specialization (const void* p1)
1027 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1030 /* Like register_specialization, but for local declarations. We are
1031 registering SPEC, an instantiation of TMPL. */
1034 register_local_specialization (tree spec, tree tmpl)
1038 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1039 htab_hash_pointer (tmpl), INSERT);
1040 *slot = build_tree_list (spec, tmpl);
1043 /* Print the list of candidate FNS in an error message. */
1046 print_candidates (tree fns)
1050 const char *str = "candidates are:";
1052 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1056 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1057 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
1062 /* Returns the template (one of the functions given by TEMPLATE_ID)
1063 which can be specialized to match the indicated DECL with the
1064 explicit template args given in TEMPLATE_ID. The DECL may be
1065 NULL_TREE if none is available. In that case, the functions in
1066 TEMPLATE_ID are non-members.
1068 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1069 specialization of a member template.
1071 The template args (those explicitly specified and those deduced)
1072 are output in a newly created vector *TARGS_OUT.
1074 If it is impossible to determine the result, an error message is
1075 issued. The error_mark_node is returned to indicate failure. */
1078 determine_specialization (tree template_id,
1081 int need_member_template)
1085 tree explicit_targs;
1086 tree candidates = NULL_TREE;
1087 tree templates = NULL_TREE;
1089 *targs_out = NULL_TREE;
1091 if (template_id == error_mark_node)
1092 return error_mark_node;
1094 fns = TREE_OPERAND (template_id, 0);
1095 explicit_targs = TREE_OPERAND (template_id, 1);
1097 if (fns == error_mark_node)
1098 return error_mark_node;
1100 /* Check for baselinks. */
1101 if (BASELINK_P (fns))
1102 fns = BASELINK_FUNCTIONS (fns);
1104 if (!is_overloaded_fn (fns))
1106 error ("`%D' is not a function template", fns);
1107 return error_mark_node;
1110 for (; fns; fns = OVL_NEXT (fns))
1112 tree fn = OVL_CURRENT (fns);
1114 if (TREE_CODE (fn) == TEMPLATE_DECL)
1116 tree decl_arg_types;
1118 /* DECL might be a specialization of FN. */
1120 /* Adjust the type of DECL in case FN is a static member. */
1121 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1122 if (DECL_STATIC_FUNCTION_P (fn)
1123 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1124 decl_arg_types = TREE_CHAIN (decl_arg_types);
1126 /* Check that the number of function parameters matches.
1128 template <class T> void f(int i = 0);
1129 template <> void f<int>();
1130 The specialization f<int> is invalid but is not caught
1131 by get_bindings below. */
1133 if (list_length (TYPE_ARG_TYPES (TREE_TYPE (fn)))
1134 != list_length (decl_arg_types))
1137 /* See whether this function might be a specialization of this
1139 targs = get_bindings (fn, decl, explicit_targs);
1142 /* We cannot deduce template arguments that when used to
1143 specialize TMPL will produce DECL. */
1146 /* Save this template, and the arguments deduced. */
1147 templates = tree_cons (targs, fn, templates);
1149 else if (need_member_template)
1150 /* FN is an ordinary member function, and we need a
1151 specialization of a member template. */
1153 else if (TREE_CODE (fn) != FUNCTION_DECL)
1154 /* We can get IDENTIFIER_NODEs here in certain erroneous
1157 else if (!DECL_FUNCTION_MEMBER_P (fn))
1158 /* This is just an ordinary non-member function. Nothing can
1159 be a specialization of that. */
1161 else if (DECL_ARTIFICIAL (fn))
1162 /* Cannot specialize functions that are created implicitly. */
1166 tree decl_arg_types;
1168 /* This is an ordinary member function. However, since
1169 we're here, we can assume it's enclosing class is a
1170 template class. For example,
1172 template <typename T> struct S { void f(); };
1173 template <> void S<int>::f() {}
1175 Here, S<int>::f is a non-template, but S<int> is a
1176 template class. If FN has the same type as DECL, we
1177 might be in business. */
1179 if (!DECL_TEMPLATE_INFO (fn))
1180 /* Its enclosing class is an explicit specialization
1181 of a template class. This is not a candidate. */
1184 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1185 TREE_TYPE (TREE_TYPE (fn))))
1186 /* The return types differ. */
1189 /* Adjust the type of DECL in case FN is a static member. */
1190 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1191 if (DECL_STATIC_FUNCTION_P (fn)
1192 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1193 decl_arg_types = TREE_CHAIN (decl_arg_types);
1195 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1198 candidates = tree_cons (NULL_TREE, fn, candidates);
1202 if (templates && TREE_CHAIN (templates))
1208 It is possible for a specialization with a given function
1209 signature to be instantiated from more than one function
1210 template. In such cases, explicit specification of the
1211 template arguments must be used to uniquely identify the
1212 function template specialization being specialized.
1214 Note that here, there's no suggestion that we're supposed to
1215 determine which of the candidate templates is most
1216 specialized. However, we, also have:
1220 Partial ordering of overloaded function template
1221 declarations is used in the following contexts to select
1222 the function template to which a function template
1223 specialization refers:
1225 -- when an explicit specialization refers to a function
1228 So, we do use the partial ordering rules, at least for now.
1229 This extension can only serve to make invalid programs valid,
1230 so it's safe. And, there is strong anecdotal evidence that
1231 the committee intended the partial ordering rules to apply;
1232 the EDG front-end has that behavior, and John Spicer claims
1233 that the committee simply forgot to delete the wording in
1234 [temp.expl.spec]. */
1235 tree tmpl = most_specialized (templates, decl, explicit_targs);
1236 if (tmpl && tmpl != error_mark_node)
1238 targs = get_bindings (tmpl, decl, explicit_targs);
1239 templates = tree_cons (targs, tmpl, NULL_TREE);
1243 if (templates == NULL_TREE && candidates == NULL_TREE)
1245 cp_error_at ("template-id `%D' for `%+D' does not match any template declaration",
1247 return error_mark_node;
1249 else if ((templates && TREE_CHAIN (templates))
1250 || (candidates && TREE_CHAIN (candidates))
1251 || (templates && candidates))
1253 cp_error_at ("ambiguous template specialization `%D' for `%+D'",
1255 chainon (candidates, templates);
1256 print_candidates (candidates);
1257 return error_mark_node;
1260 /* We have one, and exactly one, match. */
1263 /* It was a specialization of an ordinary member function in a
1265 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1266 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1269 /* It was a specialization of a template. */
1270 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1271 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1273 *targs_out = copy_node (targs);
1274 SET_TMPL_ARGS_LEVEL (*targs_out,
1275 TMPL_ARGS_DEPTH (*targs_out),
1276 TREE_PURPOSE (templates));
1279 *targs_out = TREE_PURPOSE (templates);
1280 return TREE_VALUE (templates);
1283 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1284 but with the default argument values filled in from those in the
1288 copy_default_args_to_explicit_spec_1 (tree spec_types,
1291 tree new_spec_types;
1296 if (spec_types == void_list_node)
1297 return void_list_node;
1299 /* Substitute into the rest of the list. */
1301 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1302 TREE_CHAIN (tmpl_types));
1304 /* Add the default argument for this parameter. */
1305 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1306 TREE_VALUE (spec_types),
1310 /* DECL is an explicit specialization. Replicate default arguments
1311 from the template it specializes. (That way, code like:
1313 template <class T> void f(T = 3);
1314 template <> void f(double);
1317 works, as required.) An alternative approach would be to look up
1318 the correct default arguments at the call-site, but this approach
1319 is consistent with how implicit instantiations are handled. */
1322 copy_default_args_to_explicit_spec (tree decl)
1327 tree new_spec_types;
1331 tree object_type = NULL_TREE;
1332 tree in_charge = NULL_TREE;
1333 tree vtt = NULL_TREE;
1335 /* See if there's anything we need to do. */
1336 tmpl = DECL_TI_TEMPLATE (decl);
1337 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1338 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1339 if (TREE_PURPOSE (t))
1344 old_type = TREE_TYPE (decl);
1345 spec_types = TYPE_ARG_TYPES (old_type);
1347 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1349 /* Remove the this pointer, but remember the object's type for
1351 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1352 spec_types = TREE_CHAIN (spec_types);
1353 tmpl_types = TREE_CHAIN (tmpl_types);
1355 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1357 /* DECL may contain more parameters than TMPL due to the extra
1358 in-charge parameter in constructors and destructors. */
1359 in_charge = spec_types;
1360 spec_types = TREE_CHAIN (spec_types);
1362 if (DECL_HAS_VTT_PARM_P (decl))
1365 spec_types = TREE_CHAIN (spec_types);
1369 /* Compute the merged default arguments. */
1371 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1373 /* Compute the new FUNCTION_TYPE. */
1377 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1382 /* Put the in-charge parameter back. */
1383 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1384 TREE_VALUE (in_charge),
1387 new_type = build_cplus_method_type (object_type,
1388 TREE_TYPE (old_type),
1392 new_type = build_function_type (TREE_TYPE (old_type),
1394 new_type = build_type_attribute_variant (new_type,
1395 TYPE_ATTRIBUTES (old_type));
1396 new_type = build_exception_variant (new_type,
1397 TYPE_RAISES_EXCEPTIONS (old_type));
1398 TREE_TYPE (decl) = new_type;
1401 /* Check to see if the function just declared, as indicated in
1402 DECLARATOR, and in DECL, is a specialization of a function
1403 template. We may also discover that the declaration is an explicit
1404 instantiation at this point.
1406 Returns DECL, or an equivalent declaration that should be used
1407 instead if all goes well. Issues an error message if something is
1408 amiss. Returns error_mark_node if the error is not easily
1411 FLAGS is a bitmask consisting of the following flags:
1413 2: The function has a definition.
1414 4: The function is a friend.
1416 The TEMPLATE_COUNT is the number of references to qualifying
1417 template classes that appeared in the name of the function. For
1420 template <class T> struct S { void f(); };
1423 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1424 classes are not counted in the TEMPLATE_COUNT, so that in
1426 template <class T> struct S {};
1427 template <> struct S<int> { void f(); }
1428 template <> void S<int>::f();
1430 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1431 invalid; there should be no template <>.)
1433 If the function is a specialization, it is marked as such via
1434 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1435 is set up correctly, and it is added to the list of specializations
1436 for that template. */
1439 check_explicit_specialization (tree declarator,
1444 int have_def = flags & 2;
1445 int is_friend = flags & 4;
1446 int specialization = 0;
1447 int explicit_instantiation = 0;
1448 int member_specialization = 0;
1449 tree ctype = DECL_CLASS_CONTEXT (decl);
1450 tree dname = DECL_NAME (decl);
1453 tsk = current_tmpl_spec_kind (template_count);
1458 if (processing_specialization)
1461 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1463 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1466 /* This could be something like:
1468 template <class T> void f(T);
1469 class S { friend void f<>(int); } */
1473 /* This case handles bogus declarations like template <>
1474 template <class T> void f<int>(); */
1476 error ("template-id `%D' in declaration of primary template",
1483 case tsk_invalid_member_spec:
1484 /* The error has already been reported in
1485 check_specialization_scope. */
1486 return error_mark_node;
1488 case tsk_invalid_expl_inst:
1489 error ("template parameter list used in explicit instantiation");
1495 error ("definition provided for explicit instantiation");
1497 explicit_instantiation = 1;
1500 case tsk_excessive_parms:
1501 error ("too many template parameter lists in declaration of `%D'",
1503 return error_mark_node;
1507 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1509 member_specialization = 1;
1514 case tsk_insufficient_parms:
1515 if (template_header_count)
1517 error("too few template parameter lists in declaration of `%D'",
1521 else if (ctype != NULL_TREE
1522 && !TYPE_BEING_DEFINED (ctype)
1523 && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype)
1526 /* For backwards compatibility, we accept:
1528 template <class T> struct S { void f(); };
1529 void S<int>::f() {} // Missing template <>
1531 That used to be valid C++. */
1534 ("explicit specialization not preceded by `template <>'");
1536 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1541 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1543 /* This case handles bogus declarations like template <>
1544 template <class T> void f<int>(); */
1546 if (uses_template_parms (declarator))
1547 error ("partial specialization `%D' of function template",
1550 error ("template-id `%D' in declaration of primary template",
1555 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1556 /* This is a specialization of a member template, without
1557 specialization the containing class. Something like:
1559 template <class T> struct S {
1560 template <class U> void f (U);
1562 template <> template <class U> void S<int>::f(U) {}
1564 That's a specialization -- but of the entire template. */
1572 if (specialization || member_specialization)
1574 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1575 for (; t; t = TREE_CHAIN (t))
1576 if (TREE_PURPOSE (t))
1579 ("default argument specified in explicit specialization");
1582 if (current_lang_name == lang_name_c)
1583 error ("template specialization with C linkage");
1586 if (specialization || member_specialization || explicit_instantiation)
1588 tree tmpl = NULL_TREE;
1589 tree targs = NULL_TREE;
1591 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1592 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1596 my_friendly_assert (TREE_CODE (declarator) == IDENTIFIER_NODE, 0);
1601 /* If there is no class context, the explicit instantiation
1602 must be at namespace scope. */
1603 my_friendly_assert (DECL_NAMESPACE_SCOPE_P (decl), 20030625);
1605 /* Find the namespace binding, using the declaration
1607 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1610 declarator = lookup_template_function (fns, NULL_TREE);
1613 if (declarator == error_mark_node)
1614 return error_mark_node;
1616 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1618 if (!explicit_instantiation)
1619 /* A specialization in class scope. This is invalid,
1620 but the error will already have been flagged by
1621 check_specialization_scope. */
1622 return error_mark_node;
1625 /* It's not valid to write an explicit instantiation in
1628 class C { template void f(); }
1630 This case is caught by the parser. However, on
1633 template class C { void f(); };
1635 (which is invalid) we can get here. The error will be
1642 else if (TREE_CODE (TREE_OPERAND (declarator, 0)) == LOOKUP_EXPR)
1644 /* A friend declaration. We can't do much, because we don't
1645 know what this resolves to, yet. */
1646 my_friendly_assert (is_friend != 0, 0);
1647 my_friendly_assert (!explicit_instantiation, 0);
1648 SET_DECL_IMPLICIT_INSTANTIATION (decl);
1651 else if (ctype != NULL_TREE
1652 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1655 /* Find the list of functions in ctype that have the same
1656 name as the declared function. */
1657 tree name = TREE_OPERAND (declarator, 0);
1658 tree fns = NULL_TREE;
1661 if (constructor_name_p (name, ctype))
1663 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1665 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1666 : !TYPE_HAS_DESTRUCTOR (ctype))
1668 /* From [temp.expl.spec]:
1670 If such an explicit specialization for the member
1671 of a class template names an implicitly-declared
1672 special member function (clause _special_), the
1673 program is ill-formed.
1675 Similar language is found in [temp.explicit]. */
1676 error ("specialization of implicitly-declared special member function");
1677 return error_mark_node;
1680 name = is_constructor ? ctor_identifier : dtor_identifier;
1683 if (!DECL_CONV_FN_P (decl))
1685 idx = lookup_fnfields_1 (ctype, name);
1687 fns = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (ctype), idx);
1693 /* For a type-conversion operator, we cannot do a
1694 name-based lookup. We might be looking for `operator
1695 int' which will be a specialization of `operator T'.
1696 So, we find *all* the conversion operators, and then
1697 select from them. */
1700 methods = CLASSTYPE_METHOD_VEC (ctype);
1702 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1703 idx < TREE_VEC_LENGTH (methods); ++idx)
1705 tree ovl = TREE_VEC_ELT (methods, idx);
1707 if (!ovl || !DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1708 /* There are no more conversion functions. */
1711 /* Glue all these conversion functions together
1712 with those we already have. */
1713 for (; ovl; ovl = OVL_NEXT (ovl))
1714 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1718 if (fns == NULL_TREE)
1720 error ("no member function `%D' declared in `%T'",
1722 return error_mark_node;
1725 TREE_OPERAND (declarator, 0) = fns;
1728 /* Figure out what exactly is being specialized at this point.
1729 Note that for an explicit instantiation, even one for a
1730 member function, we cannot tell apriori whether the
1731 instantiation is for a member template, or just a member
1732 function of a template class. Even if a member template is
1733 being instantiated, the member template arguments may be
1734 elided if they can be deduced from the rest of the
1736 tmpl = determine_specialization (declarator, decl,
1738 member_specialization);
1740 if (!tmpl || tmpl == error_mark_node)
1741 /* We couldn't figure out what this declaration was
1743 return error_mark_node;
1746 tree gen_tmpl = most_general_template (tmpl);
1748 if (explicit_instantiation)
1750 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
1751 is done by do_decl_instantiation later. */
1753 int arg_depth = TMPL_ARGS_DEPTH (targs);
1754 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
1756 if (arg_depth > parm_depth)
1758 /* If TMPL is not the most general template (for
1759 example, if TMPL is a friend template that is
1760 injected into namespace scope), then there will
1761 be too many levels of TARGS. Remove some of them
1766 new_targs = make_tree_vec (parm_depth);
1767 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
1768 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
1769 = TREE_VEC_ELT (targs, i);
1773 return instantiate_template (tmpl, targs, tf_error);
1776 /* If we thought that the DECL was a member function, but it
1777 turns out to be specializing a static member function,
1778 make DECL a static member function as well. We also have
1779 to adjust last_function_parms to avoid confusing
1780 start_function later. */
1781 if (DECL_STATIC_FUNCTION_P (tmpl)
1782 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1784 revert_static_member_fn (decl);
1785 last_function_parms = TREE_CHAIN (last_function_parms);
1788 /* If this is a specialization of a member template of a
1789 template class. In we want to return the TEMPLATE_DECL,
1790 not the specialization of it. */
1791 if (tsk == tsk_template)
1793 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
1794 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
1797 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
1798 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
1799 = DECL_SOURCE_LOCATION (decl);
1804 /* Set up the DECL_TEMPLATE_INFO for DECL. */
1805 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
1807 /* Inherit default function arguments from the template
1808 DECL is specializing. */
1809 copy_default_args_to_explicit_spec (decl);
1811 /* This specialization has the same protection as the
1812 template it specializes. */
1813 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
1814 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
1816 if (is_friend && !have_def)
1817 /* This is not really a declaration of a specialization.
1818 It's just the name of an instantiation. But, it's not
1819 a request for an instantiation, either. */
1820 SET_DECL_IMPLICIT_INSTANTIATION (decl);
1821 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
1822 /* This is indeed a specialization. In case of constructors
1823 and destructors, we need in-charge and not-in-charge
1824 versions in V3 ABI. */
1825 clone_function_decl (decl, /*update_method_vec_p=*/0);
1827 /* Register this specialization so that we can find it
1829 decl = register_specialization (decl, gen_tmpl, targs);
1836 /* TYPE is being declared. Verify that the use of template headers
1837 and such is reasonable. Issue error messages if not. */
1840 maybe_check_template_type (tree type)
1842 if (template_header_count)
1844 /* We are in the scope of some `template <...>' header. */
1847 = template_class_depth_real (TYPE_CONTEXT (type),
1848 /*count_specializations=*/1);
1850 if (template_header_count <= context_depth)
1851 /* This is OK; the template headers are for the context. We
1852 are actually too lenient here; like
1853 check_explicit_specialization we should consider the number
1854 of template types included in the actual declaration. For
1857 template <class T> struct S {
1858 template <class U> template <class V>
1864 template <class T> struct S {
1865 template <class U> struct I;
1868 template <class T> template <class U.
1873 else if (template_header_count > context_depth + 1)
1874 /* There are two many template parameter lists. */
1875 error ("too many template parameter lists in declaration of `%T'", type);
1879 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
1880 parameters. These are represented in the same format used for
1881 DECL_TEMPLATE_PARMS. */
1883 int comp_template_parms (tree parms1, tree parms2)
1888 if (parms1 == parms2)
1891 for (p1 = parms1, p2 = parms2;
1892 p1 != NULL_TREE && p2 != NULL_TREE;
1893 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
1895 tree t1 = TREE_VALUE (p1);
1896 tree t2 = TREE_VALUE (p2);
1899 my_friendly_assert (TREE_CODE (t1) == TREE_VEC, 0);
1900 my_friendly_assert (TREE_CODE (t2) == TREE_VEC, 0);
1902 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
1905 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
1907 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
1908 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
1910 if (TREE_CODE (parm1) != TREE_CODE (parm2))
1913 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
1915 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
1920 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
1921 /* One set of parameters has more parameters lists than the
1928 /* Complain if DECL shadows a template parameter.
1930 [temp.local]: A template-parameter shall not be redeclared within its
1931 scope (including nested scopes). */
1934 check_template_shadow (tree decl)
1938 /* If we're not in a template, we can't possibly shadow a template
1940 if (!current_template_parms)
1943 /* Figure out what we're shadowing. */
1944 if (TREE_CODE (decl) == OVERLOAD)
1945 decl = OVL_CURRENT (decl);
1946 olddecl = IDENTIFIER_VALUE (DECL_NAME (decl));
1948 /* If there's no previous binding for this name, we're not shadowing
1949 anything, let alone a template parameter. */
1953 /* If we're not shadowing a template parameter, we're done. Note
1954 that OLDDECL might be an OVERLOAD (or perhaps even an
1955 ERROR_MARK), so we can't just blithely assume it to be a _DECL
1957 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
1960 /* We check for decl != olddecl to avoid bogus errors for using a
1961 name inside a class. We check TPFI to avoid duplicate errors for
1962 inline member templates. */
1964 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
1967 cp_error_at ("declaration of `%#D'", decl);
1968 cp_error_at (" shadows template parm `%#D'", olddecl);
1971 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
1972 ORIG_LEVEL, DECL, and TYPE. */
1975 build_template_parm_index (int index,
1981 tree t = make_node (TEMPLATE_PARM_INDEX);
1982 TEMPLATE_PARM_IDX (t) = index;
1983 TEMPLATE_PARM_LEVEL (t) = level;
1984 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
1985 TEMPLATE_PARM_DECL (t) = decl;
1986 TREE_TYPE (t) = type;
1987 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
1988 TREE_READONLY (t) = TREE_READONLY (decl);
1993 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
1994 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
1995 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
1996 new one is created. */
1999 reduce_template_parm_level (tree index, tree type, int levels)
2001 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2002 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2003 != TEMPLATE_PARM_LEVEL (index) - levels))
2005 tree orig_decl = TEMPLATE_PARM_DECL (index);
2008 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2009 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2010 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2011 DECL_ARTIFICIAL (decl) = 1;
2012 SET_DECL_TEMPLATE_PARM_P (decl);
2014 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2015 TEMPLATE_PARM_LEVEL (index) - levels,
2016 TEMPLATE_PARM_ORIG_LEVEL (index),
2018 TEMPLATE_PARM_DESCENDANTS (index) = t;
2020 /* Template template parameters need this. */
2021 DECL_TEMPLATE_PARMS (decl)
2022 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2025 return TEMPLATE_PARM_DESCENDANTS (index);
2028 /* Process information from new template parameter NEXT and append it to the
2029 LIST being built. */
2032 process_template_parm (tree list, tree next)
2040 my_friendly_assert (TREE_CODE (parm) == TREE_LIST, 259);
2041 defval = TREE_PURPOSE (parm);
2042 parm = TREE_VALUE (parm);
2043 is_type = TREE_PURPOSE (parm) == class_type_node;
2047 tree p = TREE_VALUE (tree_last (list));
2049 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2050 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2052 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2060 my_friendly_assert (TREE_CODE (TREE_PURPOSE (parm)) == TREE_LIST, 260);
2061 /* is a const-param */
2062 parm = grokdeclarator (TREE_VALUE (parm), TREE_PURPOSE (parm),
2064 SET_DECL_TEMPLATE_PARM_P (parm);
2068 The top-level cv-qualifiers on the template-parameter are
2069 ignored when determining its type. */
2070 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2072 /* A template parameter is not modifiable. */
2073 TREE_READONLY (parm) = TREE_CONSTANT (parm) = 1;
2074 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2075 TREE_TYPE (parm) = void_type_node;
2076 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2077 TREE_CONSTANT (decl) = TREE_READONLY (decl) = 1;
2078 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2079 = build_template_parm_index (idx, processing_template_decl,
2080 processing_template_decl,
2081 decl, TREE_TYPE (parm));
2086 parm = TREE_VALUE (parm);
2088 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2090 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2091 /* This is for distinguishing between real templates and template
2092 template parameters */
2093 TREE_TYPE (parm) = t;
2094 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2099 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2100 /* parm is either IDENTIFIER_NODE or NULL_TREE */
2101 decl = build_decl (TYPE_DECL, parm, t);
2104 TYPE_NAME (t) = decl;
2105 TYPE_STUB_DECL (t) = decl;
2107 TEMPLATE_TYPE_PARM_INDEX (t)
2108 = build_template_parm_index (idx, processing_template_decl,
2109 processing_template_decl,
2110 decl, TREE_TYPE (parm));
2112 DECL_ARTIFICIAL (decl) = 1;
2113 SET_DECL_TEMPLATE_PARM_P (decl);
2115 parm = build_tree_list (defval, parm);
2116 return chainon (list, parm);
2119 /* The end of a template parameter list has been reached. Process the
2120 tree list into a parameter vector, converting each parameter into a more
2121 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2125 end_template_parm_list (tree parms)
2129 tree saved_parmlist = make_tree_vec (list_length (parms));
2131 current_template_parms
2132 = tree_cons (size_int (processing_template_decl),
2133 saved_parmlist, current_template_parms);
2135 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2137 next = TREE_CHAIN (parm);
2138 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2139 TREE_CHAIN (parm) = NULL_TREE;
2142 --processing_template_parmlist;
2144 return saved_parmlist;
2147 /* end_template_decl is called after a template declaration is seen. */
2150 end_template_decl (void)
2152 reset_specialization ();
2154 if (! processing_template_decl)
2157 /* This matches the pushlevel in begin_template_parm_list. */
2160 --processing_template_decl;
2161 current_template_parms = TREE_CHAIN (current_template_parms);
2164 /* Given a template argument vector containing the template PARMS.
2165 The innermost PARMS are given first. */
2168 current_template_args (void)
2171 tree args = NULL_TREE;
2172 int length = TMPL_PARMS_DEPTH (current_template_parms);
2175 /* If there is only one level of template parameters, we do not
2176 create a TREE_VEC of TREE_VECs. Instead, we return a single
2177 TREE_VEC containing the arguments. */
2179 args = make_tree_vec (length);
2181 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2183 tree a = copy_node (TREE_VALUE (header));
2186 TREE_TYPE (a) = NULL_TREE;
2187 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2189 tree t = TREE_VEC_ELT (a, i);
2191 /* T will be a list if we are called from within a
2192 begin/end_template_parm_list pair, but a vector directly
2193 if within a begin/end_member_template_processing pair. */
2194 if (TREE_CODE (t) == TREE_LIST)
2198 if (TREE_CODE (t) == TYPE_DECL
2199 || TREE_CODE (t) == TEMPLATE_DECL)
2202 t = DECL_INITIAL (t);
2203 TREE_VEC_ELT (a, i) = t;
2208 TREE_VEC_ELT (args, --l) = a;
2216 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2217 template PARMS. Used by push_template_decl below. */
2220 build_template_decl (tree decl, tree parms)
2222 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2223 DECL_TEMPLATE_PARMS (tmpl) = parms;
2224 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2225 if (DECL_LANG_SPECIFIC (decl))
2227 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2228 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2229 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2230 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2231 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2232 if (DECL_OVERLOADED_OPERATOR_P (decl))
2233 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2234 DECL_OVERLOADED_OPERATOR_P (decl));
2240 struct template_parm_data
2242 /* The level of the template parameters we are currently
2246 /* The index of the specialization argument we are currently
2250 /* An array whose size is the number of template parameters. The
2251 elements are nonzero if the parameter has been used in any one
2252 of the arguments processed so far. */
2255 /* An array whose size is the number of template arguments. The
2256 elements are nonzero if the argument makes use of template
2257 parameters of this level. */
2258 int* arg_uses_template_parms;
2261 /* Subroutine of push_template_decl used to see if each template
2262 parameter in a partial specialization is used in the explicit
2263 argument list. If T is of the LEVEL given in DATA (which is
2264 treated as a template_parm_data*), then DATA->PARMS is marked
2268 mark_template_parm (tree t, void* data)
2272 struct template_parm_data* tpd = (struct template_parm_data*) data;
2274 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2276 level = TEMPLATE_PARM_LEVEL (t);
2277 idx = TEMPLATE_PARM_IDX (t);
2281 level = TEMPLATE_TYPE_LEVEL (t);
2282 idx = TEMPLATE_TYPE_IDX (t);
2285 if (level == tpd->level)
2287 tpd->parms[idx] = 1;
2288 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2291 /* Return zero so that for_each_template_parm will continue the
2292 traversal of the tree; we want to mark *every* template parm. */
2296 /* Process the partial specialization DECL. */
2299 process_partial_specialization (tree decl)
2301 tree type = TREE_TYPE (decl);
2302 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2303 tree specargs = CLASSTYPE_TI_ARGS (type);
2304 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2305 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2306 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2307 int nargs = TREE_VEC_LENGTH (inner_args);
2308 int ntparms = TREE_VEC_LENGTH (inner_parms);
2310 int did_error_intro = 0;
2311 struct template_parm_data tpd;
2312 struct template_parm_data tpd2;
2314 /* We check that each of the template parameters given in the
2315 partial specialization is used in the argument list to the
2316 specialization. For example:
2318 template <class T> struct S;
2319 template <class T> struct S<T*>;
2321 The second declaration is OK because `T*' uses the template
2322 parameter T, whereas
2324 template <class T> struct S<int>;
2326 is no good. Even trickier is:
2337 The S2<T> declaration is actually invalid; it is a
2338 full-specialization. Of course,
2341 struct S2<T (*)(U)>;
2343 or some such would have been OK. */
2344 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2345 tpd.parms = alloca (sizeof (int) * ntparms);
2346 memset (tpd.parms, 0, sizeof (int) * ntparms);
2348 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2349 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2350 for (i = 0; i < nargs; ++i)
2352 tpd.current_arg = i;
2353 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2354 &mark_template_parm,
2358 for (i = 0; i < ntparms; ++i)
2359 if (tpd.parms[i] == 0)
2361 /* One of the template parms was not used in the
2363 if (!did_error_intro)
2365 error ("template parameters not used in partial specialization:");
2366 did_error_intro = 1;
2370 TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2373 /* [temp.class.spec]
2375 The argument list of the specialization shall not be identical to
2376 the implicit argument list of the primary template. */
2377 if (comp_template_args
2379 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2381 error ("partial specialization `%T' does not specialize any template arguments", type);
2383 /* [temp.class.spec]
2385 A partially specialized non-type argument expression shall not
2386 involve template parameters of the partial specialization except
2387 when the argument expression is a simple identifier.
2389 The type of a template parameter corresponding to a specialized
2390 non-type argument shall not be dependent on a parameter of the
2392 my_friendly_assert (nargs == DECL_NTPARMS (maintmpl), 0);
2394 for (i = 0; i < nargs; ++i)
2396 tree arg = TREE_VEC_ELT (inner_args, i);
2397 if (/* These first two lines are the `non-type' bit. */
2399 && TREE_CODE (arg) != TEMPLATE_DECL
2400 /* This next line is the `argument expression is not just a
2401 simple identifier' condition and also the `specialized
2402 non-type argument' bit. */
2403 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2405 if (tpd.arg_uses_template_parms[i])
2406 error ("template argument `%E' involves template parameter(s)", arg);
2409 /* Look at the corresponding template parameter,
2410 marking which template parameters its type depends
2413 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2418 /* We haven't yet initialized TPD2. Do so now. */
2419 tpd2.arg_uses_template_parms
2420 = (int*) alloca (sizeof (int) * nargs);
2421 /* The number of parameters here is the number in the
2422 main template, which, as checked in the assertion
2424 tpd2.parms = (int*) alloca (sizeof (int) * nargs);
2426 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2429 /* Mark the template parameters. But this time, we're
2430 looking for the template parameters of the main
2431 template, not in the specialization. */
2432 tpd2.current_arg = i;
2433 tpd2.arg_uses_template_parms[i] = 0;
2434 memset (tpd2.parms, 0, sizeof (int) * nargs);
2435 for_each_template_parm (type,
2436 &mark_template_parm,
2440 if (tpd2.arg_uses_template_parms [i])
2442 /* The type depended on some template parameters.
2443 If they are fully specialized in the
2444 specialization, that's OK. */
2446 for (j = 0; j < nargs; ++j)
2447 if (tpd2.parms[j] != 0
2448 && tpd.arg_uses_template_parms [j])
2450 error ("type `%T' of template argument `%E' depends on template parameter(s)",
2460 if (retrieve_specialization (maintmpl, specargs))
2461 /* We've already got this specialization. */
2464 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2465 = tree_cons (inner_args, inner_parms,
2466 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2467 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2471 /* Check that a template declaration's use of default arguments is not
2472 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2473 nonzero if DECL is the thing declared by a primary template.
2474 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2477 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2480 int last_level_to_check;
2485 A default template-argument shall not be specified in a
2486 function template declaration or a function template definition, nor
2487 in the template-parameter-list of the definition of a member of a
2490 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2491 /* You can't have a function template declaration in a local
2492 scope, nor you can you define a member of a class template in a
2496 if (current_class_type
2497 && !TYPE_BEING_DEFINED (current_class_type)
2498 && DECL_LANG_SPECIFIC (decl)
2499 /* If this is either a friend defined in the scope of the class
2500 or a member function. */
2501 && (DECL_FUNCTION_MEMBER_P (decl)
2502 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2503 : DECL_FRIEND_CONTEXT (decl)
2504 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2506 /* And, if it was a member function, it really was defined in
2507 the scope of the class. */
2508 && (!DECL_FUNCTION_MEMBER_P (decl)
2509 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2510 /* We already checked these parameters when the template was
2511 declared, so there's no need to do it again now. This function
2512 was defined in class scope, but we're processing it's body now
2513 that the class is complete. */
2518 If a template-parameter has a default template-argument, all
2519 subsequent template-parameters shall have a default
2520 template-argument supplied. */
2521 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2523 tree inner_parms = TREE_VALUE (parm_level);
2524 int ntparms = TREE_VEC_LENGTH (inner_parms);
2525 int seen_def_arg_p = 0;
2528 for (i = 0; i < ntparms; ++i)
2530 tree parm = TREE_VEC_ELT (inner_parms, i);
2531 if (TREE_PURPOSE (parm))
2533 else if (seen_def_arg_p)
2535 error ("no default argument for `%D'", TREE_VALUE (parm));
2536 /* For better subsequent error-recovery, we indicate that
2537 there should have been a default argument. */
2538 TREE_PURPOSE (parm) = error_mark_node;
2543 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2544 /* For an ordinary class template, default template arguments are
2545 allowed at the innermost level, e.g.:
2546 template <class T = int>
2548 but, in a partial specialization, they're not allowed even
2549 there, as we have in [temp.class.spec]:
2551 The template parameter list of a specialization shall not
2552 contain default template argument values.
2554 So, for a partial specialization, or for a function template,
2555 we look at all of them. */
2558 /* But, for a primary class template that is not a partial
2559 specialization we look at all template parameters except the
2561 parms = TREE_CHAIN (parms);
2563 /* Figure out what error message to issue. */
2564 if (TREE_CODE (decl) == FUNCTION_DECL)
2565 msg = "default template arguments may not be used in function templates";
2566 else if (is_partial)
2567 msg = "default template arguments may not be used in partial specializations";
2569 msg = "default argument for template parameter for class enclosing `%D'";
2571 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2572 /* If we're inside a class definition, there's no need to
2573 examine the parameters to the class itself. On the one
2574 hand, they will be checked when the class is defined, and,
2575 on the other, default arguments are valid in things like:
2576 template <class T = double>
2577 struct S { template <class U> void f(U); };
2578 Here the default argument for `S' has no bearing on the
2579 declaration of `f'. */
2580 last_level_to_check = template_class_depth (current_class_type) + 1;
2582 /* Check everything. */
2583 last_level_to_check = 0;
2585 for (parm_level = parms;
2586 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2587 parm_level = TREE_CHAIN (parm_level))
2589 tree inner_parms = TREE_VALUE (parm_level);
2593 ntparms = TREE_VEC_LENGTH (inner_parms);
2594 for (i = 0; i < ntparms; ++i)
2595 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2603 /* Clear out the default argument so that we are not
2605 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2608 /* At this point, if we're still interested in issuing messages,
2609 they must apply to classes surrounding the object declared. */
2611 msg = "default argument for template parameter for class enclosing `%D'";
2615 /* Worker for push_template_decl_real, called via
2616 for_each_template_parm. DATA is really an int, indicating the
2617 level of the parameters we are interested in. If T is a template
2618 parameter of that level, return nonzero. */
2621 template_parm_this_level_p (tree t, void* data)
2623 int this_level = *(int *)data;
2626 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2627 level = TEMPLATE_PARM_LEVEL (t);
2629 level = TEMPLATE_TYPE_LEVEL (t);
2630 return level == this_level;
2633 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2634 parameters given by current_template_args, or reuses a
2635 previously existing one, if appropriate. Returns the DECL, or an
2636 equivalent one, if it is replaced via a call to duplicate_decls.
2638 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2641 push_template_decl_real (tree decl, int is_friend)
2649 int new_template_p = 0;
2651 /* See if this is a partial specialization. */
2652 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2653 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2654 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2656 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2659 /* For a friend, we want the context of the friend function, not
2660 the type of which it is a friend. */
2661 ctx = DECL_CONTEXT (decl);
2662 else if (CP_DECL_CONTEXT (decl)
2663 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2664 /* In the case of a virtual function, we want the class in which
2666 ctx = CP_DECL_CONTEXT (decl);
2668 /* Otherwise, if we're currently defining some class, the DECL
2669 is assumed to be a member of the class. */
2670 ctx = current_scope ();
2672 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2675 if (!DECL_CONTEXT (decl))
2676 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2678 /* See if this is a primary template. */
2679 primary = template_parm_scope_p ();
2683 if (current_lang_name == lang_name_c)
2684 error ("template with C linkage");
2685 else if (TREE_CODE (decl) == TYPE_DECL
2686 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2687 error ("template class without a name");
2688 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2689 && CLASS_TYPE_P (TREE_TYPE (decl)))
2690 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx))
2691 || TREE_CODE (decl) == FUNCTION_DECL)
2694 error ("template declaration of `%#D'", decl);
2697 /* Check to see that the rules regarding the use of default
2698 arguments are not being violated. */
2699 check_default_tmpl_args (decl, current_template_parms,
2700 primary, is_partial);
2703 return process_partial_specialization (decl);
2705 args = current_template_args ();
2708 || TREE_CODE (ctx) == FUNCTION_DECL
2709 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
2710 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
2712 if (DECL_LANG_SPECIFIC (decl)
2713 && DECL_TEMPLATE_INFO (decl)
2714 && DECL_TI_TEMPLATE (decl))
2715 tmpl = DECL_TI_TEMPLATE (decl);
2716 /* If DECL is a TYPE_DECL for a class-template, then there won't
2717 be DECL_LANG_SPECIFIC. The information equivalent to
2718 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2719 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
2720 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2721 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2723 /* Since a template declaration already existed for this
2724 class-type, we must be redeclaring it here. Make sure
2725 that the redeclaration is valid. */
2726 redeclare_class_template (TREE_TYPE (decl),
2727 current_template_parms);
2728 /* We don't need to create a new TEMPLATE_DECL; just use the
2729 one we already had. */
2730 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2734 tmpl = build_template_decl (decl, current_template_parms);
2737 if (DECL_LANG_SPECIFIC (decl)
2738 && DECL_TEMPLATE_SPECIALIZATION (decl))
2740 /* A specialization of a member template of a template
2742 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2743 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
2744 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
2750 tree a, t, current, parms;
2753 if (TREE_CODE (decl) == TYPE_DECL)
2755 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
2756 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
2757 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2758 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2759 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2762 error ("`%D' does not declare a template type", decl);
2766 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
2768 error ("template definition of non-template `%#D'", decl);
2772 tmpl = DECL_TI_TEMPLATE (decl);
2774 if (is_member_template (tmpl)
2775 && DECL_FUNCTION_TEMPLATE_P (tmpl)
2776 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
2777 && DECL_TEMPLATE_SPECIALIZATION (decl))
2781 /* The declaration is a specialization of a member
2782 template, declared outside the class. Therefore, the
2783 innermost template arguments will be NULL, so we
2784 replace them with the arguments determined by the
2785 earlier call to check_explicit_specialization. */
2786 args = DECL_TI_ARGS (decl);
2789 = build_template_decl (decl, current_template_parms);
2790 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
2791 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
2792 DECL_TI_TEMPLATE (decl) = new_tmpl;
2793 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
2794 DECL_TEMPLATE_INFO (new_tmpl)
2795 = tree_cons (tmpl, args, NULL_TREE);
2797 register_specialization (new_tmpl,
2798 most_general_template (tmpl),
2803 /* Make sure the template headers we got make sense. */
2805 parms = DECL_TEMPLATE_PARMS (tmpl);
2806 i = TMPL_PARMS_DEPTH (parms);
2807 if (TMPL_ARGS_DEPTH (args) != i)
2809 error ("expected %d levels of template parms for `%#D', got %d",
2810 i, decl, TMPL_ARGS_DEPTH (args));
2813 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
2815 a = TMPL_ARGS_LEVEL (args, i);
2816 t = INNERMOST_TEMPLATE_PARMS (parms);
2818 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
2820 if (current == decl)
2821 error ("got %d template parameters for `%#D'",
2822 TREE_VEC_LENGTH (a), decl);
2824 error ("got %d template parameters for `%#T'",
2825 TREE_VEC_LENGTH (a), current);
2826 error (" but %d required", TREE_VEC_LENGTH (t));
2829 /* Perhaps we should also check that the parms are used in the
2830 appropriate qualifying scopes in the declarator? */
2832 if (current == decl)
2835 current = TYPE_CONTEXT (current);
2839 DECL_TEMPLATE_RESULT (tmpl) = decl;
2840 TREE_TYPE (tmpl) = TREE_TYPE (decl);
2842 /* Push template declarations for global functions and types. Note
2843 that we do not try to push a global template friend declared in a
2844 template class; such a thing may well depend on the template
2845 parameters of the class. */
2846 if (new_template_p && !ctx
2847 && !(is_friend && template_class_depth (current_class_type) > 0))
2848 tmpl = pushdecl_namespace_level (tmpl);
2852 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
2853 if (DECL_CONV_FN_P (tmpl))
2855 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2857 /* It is a conversion operator. See if the type converted to
2858 depends on innermost template operands. */
2860 if (for_each_template_parm (TREE_TYPE (TREE_TYPE (tmpl)),
2861 template_parm_this_level_p,
2864 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
2868 info = tree_cons (tmpl, args, NULL_TREE);
2870 if (DECL_IMPLICIT_TYPEDEF_P (decl))
2872 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
2873 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
2874 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2875 /* Don't change the name if we've already set it up. */
2876 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
2877 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
2879 else if (DECL_LANG_SPECIFIC (decl))
2880 DECL_TEMPLATE_INFO (decl) = info;
2882 return DECL_TEMPLATE_RESULT (tmpl);
2886 push_template_decl (tree decl)
2888 return push_template_decl_real (decl, 0);
2891 /* Called when a class template TYPE is redeclared with the indicated
2892 template PARMS, e.g.:
2894 template <class T> struct S;
2895 template <class T> struct S {}; */
2898 redeclare_class_template (tree type, tree parms)
2904 if (!TYPE_TEMPLATE_INFO (type))
2906 error ("`%T' is not a template type", type);
2910 tmpl = TYPE_TI_TEMPLATE (type);
2911 if (!PRIMARY_TEMPLATE_P (tmpl))
2912 /* The type is nested in some template class. Nothing to worry
2913 about here; there are no new template parameters for the nested
2917 parms = INNERMOST_TEMPLATE_PARMS (parms);
2918 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
2920 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
2922 cp_error_at ("previous declaration `%D'", tmpl);
2923 error ("used %d template parameter%s instead of %d",
2924 TREE_VEC_LENGTH (tmpl_parms),
2925 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
2926 TREE_VEC_LENGTH (parms));
2930 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
2932 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
2933 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
2934 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
2935 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
2937 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm))
2939 cp_error_at ("template parameter `%#D'", tmpl_parm);
2940 error ("redeclared here as `%#D'", parm);
2944 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
2946 /* We have in [temp.param]:
2948 A template-parameter may not be given default arguments
2949 by two different declarations in the same scope. */
2950 error ("redefinition of default argument for `%#D'", parm);
2951 error ("%H original definition appeared here",
2952 &DECL_SOURCE_LOCATION (tmpl_parm));
2956 if (parm_default != NULL_TREE)
2957 /* Update the previous template parameters (which are the ones
2958 that will really count) with the new default value. */
2959 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
2960 else if (tmpl_default != NULL_TREE)
2961 /* Update the new parameters, too; they'll be used as the
2962 parameters for any members. */
2963 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
2967 /* Attempt to convert the non-type template parameter EXPR to the
2968 indicated TYPE. If the conversion is successful, return the
2969 converted value. If the conversion is unsuccessful, return
2970 NULL_TREE if we issued an error message, or error_mark_node if we
2971 did not. We issue error messages for out-and-out bad template
2972 parameters, but not simply because the conversion failed, since we
2973 might be just trying to do argument deduction. By the time this
2974 function is called, neither TYPE nor EXPR may make use of template
2978 convert_nontype_argument (tree type, tree expr)
2980 tree expr_type = TREE_TYPE (expr);
2982 /* A template-argument for a non-type, non-template
2983 template-parameter shall be one of:
2985 --an integral constant-expression of integral or enumeration
2988 --the name of a non-type template-parameter; or
2990 --the name of an object or function with external linkage,
2991 including function templates and function template-ids but
2992 excluding non-static class members, expressed as id-expression;
2995 --the address of an object or function with external linkage,
2996 including function templates and function template-ids but
2997 excluding non-static class members, expressed as & id-expression
2998 where the & is optional if the name refers to a function or
3001 --a pointer to member expressed as described in _expr.unary.op_. */
3003 /* An integral constant-expression can include const variables or
3004 enumerators. Simplify things by folding them to their values,
3005 unless we're about to bind the declaration to a reference
3007 if (INTEGRAL_TYPE_P (expr_type)
3008 && TREE_CODE (type) != REFERENCE_TYPE)
3009 expr = decl_constant_value (expr);
3011 if (is_overloaded_fn (expr))
3012 /* OK for now. We'll check that it has external linkage later.
3013 Check this first since if expr_type is the unknown_type_node
3014 we would otherwise complain below. */
3016 else if (TYPE_PTRMEM_P (expr_type)
3017 || TYPE_PTRMEMFUNC_P (expr_type))
3019 if (TREE_CODE (expr) != PTRMEM_CST)
3022 else if (TYPE_PTR_P (expr_type)
3023 || TREE_CODE (expr_type) == ARRAY_TYPE
3024 || TREE_CODE (type) == REFERENCE_TYPE
3025 /* If expr is the address of an overloaded function, we
3026 will get the unknown_type_node at this point. */
3027 || expr_type == unknown_type_node)
3033 if (TREE_CODE (expr_type) == ARRAY_TYPE
3034 || (TREE_CODE (type) == REFERENCE_TYPE
3035 && TREE_CODE (e) != ADDR_EXPR))
3039 if (TREE_CODE (e) != ADDR_EXPR)
3042 error ("`%E' is not a valid template argument", expr);
3043 if (TYPE_PTR_P (expr_type))
3045 if (TREE_CODE (TREE_TYPE (expr_type)) == FUNCTION_TYPE)
3046 error ("it must be the address of a function with external linkage");
3048 error ("it must be the address of an object with external linkage");
3050 else if (TYPE_PTRMEM_P (expr_type)
3051 || TYPE_PTRMEMFUNC_P (expr_type))
3052 error ("it must be a pointer-to-member of the form `&X::Y'");
3057 referent = TREE_OPERAND (e, 0);
3058 STRIP_NOPS (referent);
3061 if (TREE_CODE (referent) == STRING_CST)
3063 error ("string literal %E is not a valid template argument because it is the address of an object with static linkage",
3068 if (TREE_CODE (referent) == SCOPE_REF)
3069 referent = TREE_OPERAND (referent, 1);
3071 if (is_overloaded_fn (referent))
3072 /* We'll check that it has external linkage later. */
3074 else if (TREE_CODE (referent) != VAR_DECL)
3076 else if (!DECL_EXTERNAL_LINKAGE_P (referent))
3078 error ("address of non-extern `%E' cannot be used as template argument", referent);
3079 return error_mark_node;
3082 else if (INTEGRAL_TYPE_P (expr_type)
3083 || TYPE_PTRMEM_P (expr_type)
3084 || TYPE_PTRMEMFUNC_P (expr_type))
3086 if (! TREE_CONSTANT (expr))
3089 error ("non-constant `%E' cannot be used as template argument",
3096 error ("object `%E' cannot be used as template argument", expr);
3100 switch (TREE_CODE (type))
3105 /* For a non-type template-parameter of integral or enumeration
3106 type, integral promotions (_conv.prom_) and integral
3107 conversions (_conv.integral_) are applied. */
3108 if (!INTEGRAL_TYPE_P (expr_type))
3109 return error_mark_node;
3111 /* It's safe to call digest_init in this case; we know we're
3112 just converting one integral constant expression to another. */
3113 expr = digest_init (type, expr, (tree*) 0);
3115 if (TREE_CODE (expr) != INTEGER_CST)
3116 /* Curiously, some TREE_CONSTANT integral expressions do not
3117 simplify to integer constants. For example, `3 % 0',
3118 remains a TRUNC_MOD_EXPR. */
3125 tree type_pointed_to = TREE_TYPE (type);
3127 if (TYPE_PTRMEM_P (type))
3131 /* For a non-type template-parameter of type pointer to data
3132 member, qualification conversions (_conv.qual_) are
3134 e = perform_qualification_conversions (type, expr);
3135 if (TREE_CODE (e) == NOP_EXPR)
3136 /* The call to perform_qualification_conversions will
3137 insert a NOP_EXPR over EXPR to do express conversion,
3138 if necessary. But, that will confuse us if we use
3139 this (converted) template parameter to instantiate
3140 another template; then the thing will not look like a
3141 valid template argument. So, just make a new
3142 constant, of the appropriate type. */
3143 e = make_ptrmem_cst (type, PTRMEM_CST_MEMBER (expr));
3146 else if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE)
3148 /* For a non-type template-parameter of type pointer to
3149 function, only the function-to-pointer conversion
3150 (_conv.func_) is applied. If the template-argument
3151 represents a set of overloaded functions (or a pointer to
3152 such), the matching function is selected from the set
3157 if (TREE_CODE (expr) == ADDR_EXPR)
3158 fns = TREE_OPERAND (expr, 0);
3162 fn = instantiate_type (type_pointed_to, fns, tf_none);
3164 if (fn == error_mark_node)
3165 return error_mark_node;
3167 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3169 if (really_overloaded_fn (fns))
3170 return error_mark_node;
3175 expr = build_unary_op (ADDR_EXPR, fn, 0);
3177 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3183 /* For a non-type template-parameter of type pointer to
3184 object, qualification conversions (_conv.qual_) and the
3185 array-to-pointer conversion (_conv.array_) are applied.
3186 [Note: In particular, neither the null pointer conversion
3187 (_conv.ptr_) nor the derived-to-base conversion
3188 (_conv.ptr_) are applied. Although 0 is a valid
3189 template-argument for a non-type template-parameter of
3190 integral type, it is not a valid template-argument for a
3191 non-type template-parameter of pointer type.]
3193 The call to decay_conversion performs the
3194 array-to-pointer conversion, if appropriate. */
3195 expr = decay_conversion (expr);
3197 if (expr == error_mark_node)
3198 return error_mark_node;
3200 return perform_qualification_conversions (type, expr);
3205 case REFERENCE_TYPE:
3207 tree type_referred_to = TREE_TYPE (type);
3209 /* If this expression already has reference type, get the
3210 underling object. */
3211 if (TREE_CODE (expr_type) == REFERENCE_TYPE)
3213 my_friendly_assert (TREE_CODE (expr) == ADDR_EXPR, 20000604);
3214 expr = TREE_OPERAND (expr, 0);
3215 expr_type = TREE_TYPE (expr);
3218 if (TREE_CODE (type_referred_to) == FUNCTION_TYPE)
3220 /* For a non-type template-parameter of type reference to
3221 function, no conversions apply. If the
3222 template-argument represents a set of overloaded
3223 functions, the matching function is selected from the
3224 set (_over.over_). */
3227 fn = instantiate_type (type_referred_to, expr, tf_none);
3229 if (fn == error_mark_node)
3230 return error_mark_node;
3232 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3234 if (really_overloaded_fn (expr))
3235 /* Don't issue an error here; we might get a different
3236 function if the overloading had worked out
3238 return error_mark_node;
3243 my_friendly_assert (same_type_p (type_referred_to,
3251 /* For a non-type template-parameter of type reference to
3252 object, no conversions apply. The type referred to by the
3253 reference may be more cv-qualified than the (otherwise
3254 identical) type of the template-argument. The
3255 template-parameter is bound directly to the
3256 template-argument, which must be an lvalue. */
3257 if (!same_type_p (TYPE_MAIN_VARIANT (expr_type),
3258 TYPE_MAIN_VARIANT (type_referred_to))
3259 || !at_least_as_qualified_p (type_referred_to,
3261 || !real_lvalue_p (expr))
3262 return error_mark_node;
3265 cxx_mark_addressable (expr);
3266 return build1 (ADDR_EXPR, type, expr);
3272 my_friendly_assert (TYPE_PTRMEMFUNC_P (type), 20010112);
3274 /* For a non-type template-parameter of type pointer to member
3275 function, no conversions apply. If the template-argument
3276 represents a set of overloaded member functions, the
3277 matching member function is selected from the set
3280 if (!TYPE_PTRMEMFUNC_P (expr_type) &&
3281 expr_type != unknown_type_node)
3282 return error_mark_node;
3284 if (TREE_CODE (expr) == PTRMEM_CST)
3286 /* A ptr-to-member constant. */
3287 if (!same_type_p (type, expr_type))
3288 return error_mark_node;
3293 if (TREE_CODE (expr) != ADDR_EXPR)
3294 return error_mark_node;
3296 expr = instantiate_type (type, expr, tf_none);
3298 if (expr == error_mark_node)
3299 return error_mark_node;
3301 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3308 /* All non-type parameters must have one of these types. */
3313 return error_mark_node;
3316 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3317 template template parameters. Both PARM_PARMS and ARG_PARMS are
3318 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3321 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3322 the case, then extra parameters must have default arguments.
3324 Consider the example:
3325 template <class T, class Allocator = allocator> class vector;
3326 template<template <class U> class TT> class C;
3328 C<vector> is a valid instantiation. PARM_PARMS for the above code
3329 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3330 T and Allocator) and OUTER_ARGS contains the argument that is used to
3331 substitute the TT parameter. */
3334 coerce_template_template_parms (tree parm_parms,
3336 tsubst_flags_t complain,
3340 int nparms, nargs, i;
3343 my_friendly_assert (TREE_CODE (parm_parms) == TREE_VEC, 0);
3344 my_friendly_assert (TREE_CODE (arg_parms) == TREE_VEC, 0);
3346 nparms = TREE_VEC_LENGTH (parm_parms);
3347 nargs = TREE_VEC_LENGTH (arg_parms);
3349 /* The rule here is opposite of coerce_template_parms. */
3352 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3355 for (i = 0; i < nparms; ++i)
3357 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3358 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3360 if (arg == NULL_TREE || arg == error_mark_node
3361 || parm == NULL_TREE || parm == error_mark_node)
3364 if (TREE_CODE (arg) != TREE_CODE (parm))
3367 switch (TREE_CODE (parm))
3373 /* We encounter instantiations of templates like
3374 template <template <template <class> class> class TT>
3377 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3378 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3380 if (!coerce_template_template_parms (parmparm, argparm,
3388 /* The tsubst call is used to handle cases such as
3389 template <class T, template <T> class TT> class D;
3390 i.e. the parameter list of TT depends on earlier parameters. */
3391 if (!same_type_p (tsubst (TREE_TYPE (parm), outer_args,
3404 /* Convert the indicated template ARG as necessary to match the
3405 indicated template PARM. Returns the converted ARG, or
3406 error_mark_node if the conversion was unsuccessful. Error and
3407 warning messages are issued under control of COMPLAIN. This
3408 conversion is for the Ith parameter in the parameter list. ARGS is
3409 the full set of template arguments deduced so far. */
3412 convert_template_argument (tree parm,
3415 tsubst_flags_t complain,
3421 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3423 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3425 if (TREE_CODE (arg) == TREE_LIST
3426 && TREE_TYPE (arg) != NULL_TREE
3427 && TREE_CODE (TREE_TYPE (arg)) == OFFSET_TYPE)
3429 /* The template argument was the name of some
3430 member function. That's usually
3431 invalid, but static members are OK. In any
3432 case, grab the underlying fields/functions
3433 and issue an error later if required. */
3434 arg = TREE_VALUE (arg);
3435 TREE_TYPE (arg) = unknown_type_node;
3438 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3439 requires_type = (TREE_CODE (parm) == TYPE_DECL
3440 || requires_tmpl_type);
3442 if (TREE_CODE (arg) != RECORD_TYPE)
3443 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3444 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3445 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3446 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3447 else if (CLASSTYPE_TEMPLATE_INFO (arg) && !CLASSTYPE_USE_TEMPLATE (arg)
3448 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (arg)))
3450 if (is_base_of_enclosing_class (arg, current_class_type))
3451 /* This is a template name used within the scope of the
3452 template. It could be the template, or it could be the
3453 instantiation. Choose whichever makes sense. */
3454 is_tmpl_type = requires_tmpl_type;
3459 /* It is a non-template class, or a specialization of a template
3460 class, or a non-template member of a template class. */
3464 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3465 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3466 arg = TYPE_STUB_DECL (arg);
3467 else if (is_tmpl_type && TREE_CODE (arg) == RECORD_TYPE)
3468 arg = CLASSTYPE_TI_TEMPLATE (arg);
3470 is_type = TYPE_P (arg) || is_tmpl_type;
3472 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3473 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3475 pedwarn ("to refer to a type member of a template parameter, use `typename %E'", arg);
3477 arg = make_typename_type (TREE_OPERAND (arg, 0),
3478 TREE_OPERAND (arg, 1),
3479 complain & tf_error);
3482 if (is_type != requires_type)
3486 if (complain & tf_error)
3488 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3491 error (" expected a constant of type `%T', got `%T'",
3493 (is_tmpl_type ? DECL_NAME (arg) : arg));
3494 else if (requires_tmpl_type)
3495 error (" expected a class template, got `%E'", arg);
3497 error (" expected a type, got `%E'", arg);
3500 return error_mark_node;
3502 if (is_tmpl_type ^ requires_tmpl_type)
3504 if (in_decl && (complain & tf_error))
3506 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3509 error (" expected a type, got `%T'", DECL_NAME (arg));
3511 error (" expected a class template, got `%T'", arg);
3513 return error_mark_node;
3518 if (requires_tmpl_type)
3520 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3521 /* The number of argument required is not known yet.
3522 Just accept it for now. */
3523 val = TREE_TYPE (arg);
3526 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3527 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3529 if (coerce_template_template_parms (parmparm, argparm,
3535 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3537 if (val != error_mark_node
3538 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3539 val = TREE_TYPE (val);
3543 if (in_decl && (complain & tf_error))
3545 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3547 error (" expected a template of type `%D', got `%D'", parm, arg);
3550 val = error_mark_node;
3555 val = groktypename (arg);
3559 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3561 if (invalid_nontype_parm_type_p (t, complain))
3562 return error_mark_node;
3564 if (!uses_template_parms (arg) && !uses_template_parms (t))
3565 /* We used to call digest_init here. However, digest_init
3566 will report errors, which we don't want when complain
3567 is zero. More importantly, digest_init will try too
3568 hard to convert things: for example, `0' should not be
3569 converted to pointer type at this point according to
3570 the standard. Accepting this is not merely an
3571 extension, since deciding whether or not these
3572 conversions can occur is part of determining which
3573 function template to call, or whether a given explicit
3574 argument specification is valid. */
3575 val = convert_nontype_argument (t, arg);
3579 if (val == NULL_TREE)
3580 val = error_mark_node;
3581 else if (val == error_mark_node && (complain & tf_error))
3582 error ("could not convert template argument `%E' to `%T'",
3589 /* Convert all template arguments to their appropriate types, and
3590 return a vector containing the innermost resulting template
3591 arguments. If any error occurs, return error_mark_node. Error and
3592 warning messages are issued under control of COMPLAIN.
3594 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3595 provided in ARGLIST, or else trailing parameters must have default
3596 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3597 deduction for any unspecified trailing arguments. */
3600 coerce_template_parms (tree parms,
3603 tsubst_flags_t complain,
3604 int require_all_arguments)
3606 int nparms, nargs, i, lost = 0;
3609 tree new_inner_args;
3611 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3612 nargs = NUM_TMPL_ARGS (inner_args);
3613 nparms = TREE_VEC_LENGTH (parms);
3617 && require_all_arguments
3618 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3620 if (complain & tf_error)
3622 error ("wrong number of template arguments (%d, should be %d)",
3626 cp_error_at ("provided for `%D'", in_decl);
3629 return error_mark_node;
3632 new_inner_args = make_tree_vec (nparms);
3633 new_args = add_outermost_template_args (args, new_inner_args);
3634 for (i = 0; i < nparms; i++)
3639 /* Get the Ith template parameter. */
3640 parm = TREE_VEC_ELT (parms, i);
3642 /* Calculate the Ith argument. */
3643 if (inner_args && TREE_CODE (inner_args) == TREE_LIST)
3645 arg = TREE_VALUE (inner_args);
3646 inner_args = TREE_CHAIN (inner_args);
3649 arg = TREE_VEC_ELT (inner_args, i);
3650 /* If no template argument was supplied, look for a default
3652 else if (TREE_PURPOSE (parm) == NULL_TREE)
3654 /* There was no default value. */
3655 my_friendly_assert (!require_all_arguments, 0);
3658 else if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL)
3659 arg = tsubst (TREE_PURPOSE (parm), new_args, complain, in_decl);
3661 arg = tsubst_expr (TREE_PURPOSE (parm), new_args, complain,
3664 /* Now, convert the Ith argument, as necessary. */
3665 if (arg == NULL_TREE)
3666 /* We're out of arguments. */
3668 my_friendly_assert (!require_all_arguments, 0);
3671 else if (arg == error_mark_node)
3673 error ("template argument %d is invalid", i + 1);
3674 arg = error_mark_node;
3677 arg = convert_template_argument (TREE_VALUE (parm),
3678 arg, new_args, complain, i,
3681 if (arg == error_mark_node)
3683 TREE_VEC_ELT (new_inner_args, i) = arg;
3687 return error_mark_node;
3689 return new_inner_args;
3692 /* Returns 1 if template args OT and NT are equivalent. */
3695 template_args_equal (tree ot, tree nt)
3700 if (TREE_CODE (nt) == TREE_VEC)
3701 /* For member templates */
3702 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
3703 else if (TYPE_P (nt))
3704 return TYPE_P (ot) && same_type_p (ot, nt);
3705 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
3708 return cp_tree_equal (ot, nt);
3711 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
3712 of template arguments. Returns 0 otherwise. */
3715 comp_template_args (tree oldargs, tree newargs)
3719 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
3722 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
3724 tree nt = TREE_VEC_ELT (newargs, i);
3725 tree ot = TREE_VEC_ELT (oldargs, i);
3727 if (! template_args_equal (ot, nt))
3733 /* Given class template name and parameter list, produce a user-friendly name
3734 for the instantiation. */
3737 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
3739 static struct obstack scratch_obstack;
3740 static char *scratch_firstobj;
3743 if (!scratch_firstobj)
3744 gcc_obstack_init (&scratch_obstack);
3746 obstack_free (&scratch_obstack, scratch_firstobj);
3747 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
3749 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
3750 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
3754 nparms = TREE_VEC_LENGTH (parms);
3755 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
3756 my_friendly_assert (nparms == TREE_VEC_LENGTH (arglist), 268);
3757 for (i = 0; i < nparms; i++)
3759 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3760 tree arg = TREE_VEC_ELT (arglist, i);
3765 if (TREE_CODE (parm) == TYPE_DECL)
3767 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
3770 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3772 if (TREE_CODE (arg) == TEMPLATE_DECL)
3774 /* Already substituted with real template. Just output
3775 the template name here */
3776 tree context = DECL_CONTEXT (arg);
3779 /* The template may be defined in a namespace, or
3780 may be a member template. */
3781 my_friendly_assert (TREE_CODE (context) == NAMESPACE_DECL
3782 || CLASS_TYPE_P (context),
3784 cat(decl_as_string (DECL_CONTEXT (arg), TFF_PLAIN_IDENTIFIER));
3787 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
3790 /* Output the parameter declaration */
3791 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
3795 my_friendly_assert (TREE_CODE (parm) == PARM_DECL, 269);
3797 if (TREE_CODE (arg) == TREE_LIST)
3799 /* New list cell was built because old chain link was in
3801 my_friendly_assert (TREE_PURPOSE (arg) == NULL_TREE, 270);
3802 arg = TREE_VALUE (arg);
3804 /* No need to check arglist against parmlist here; we did that
3805 in coerce_template_parms, called from lookup_template_class. */
3806 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
3809 char *bufp = obstack_next_free (&scratch_obstack);
3811 while (bufp[offset - 1] == ' ')
3813 obstack_blank_fast (&scratch_obstack, offset);
3815 /* B<C<char> >, not B<C<char>> */
3816 if (bufp[offset - 1] == '>')
3821 return (char *) obstack_base (&scratch_obstack);
3825 classtype_mangled_name (tree t)
3827 if (CLASSTYPE_TEMPLATE_INFO (t)
3828 /* Specializations have already had their names set up in
3829 lookup_template_class. */
3830 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
3832 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
3834 /* For non-primary templates, the template parameters are
3835 implicit from their surrounding context. */
3836 if (PRIMARY_TEMPLATE_P (tmpl))
3838 tree name = DECL_NAME (tmpl);
3839 char *mangled_name = mangle_class_name_for_template
3840 (IDENTIFIER_POINTER (name),
3841 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
3842 CLASSTYPE_TI_ARGS (t));
3843 tree id = get_identifier (mangled_name);
3844 IDENTIFIER_TEMPLATE (id) = name;
3849 return TYPE_IDENTIFIER (t);
3853 add_pending_template (tree d)
3855 tree ti = (TYPE_P (d)
3856 ? CLASSTYPE_TEMPLATE_INFO (d)
3857 : DECL_TEMPLATE_INFO (d));
3861 if (TI_PENDING_TEMPLATE_FLAG (ti))
3864 /* We are called both from instantiate_decl, where we've already had a
3865 tinst_level pushed, and instantiate_template, where we haven't.
3867 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
3870 push_tinst_level (d);
3872 pt = tree_cons (current_tinst_level, d, NULL_TREE);
3873 if (last_pending_template)
3874 TREE_CHAIN (last_pending_template) = pt;
3876 pending_templates = pt;
3878 last_pending_template = pt;
3880 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
3887 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
3888 ARGLIST. Valid choices for FNS are given in the cp-tree.def
3889 documentation for TEMPLATE_ID_EXPR. */
3892 lookup_template_function (tree fns, tree arglist)
3896 if (fns == error_mark_node || arglist == error_mark_node)
3897 return error_mark_node;
3899 if (fns == NULL_TREE)
3901 error ("non-template used as template");
3902 return error_mark_node;
3905 my_friendly_assert (TREE_CODE (fns) == TEMPLATE_DECL
3906 || TREE_CODE (fns) == OVERLOAD
3908 || TREE_CODE (fns) == IDENTIFIER_NODE
3909 || TREE_CODE (fns) == LOOKUP_EXPR,
3912 if (BASELINK_P (fns))
3914 BASELINK_FUNCTIONS (fns) = build (TEMPLATE_ID_EXPR,
3916 BASELINK_FUNCTIONS (fns),
3921 type = TREE_TYPE (fns);
3922 if (TREE_CODE (fns) == OVERLOAD || !type)
3923 type = unknown_type_node;
3925 return build (TEMPLATE_ID_EXPR, type, fns, arglist);
3928 /* Within the scope of a template class S<T>, the name S gets bound
3929 (in build_self_reference) to a TYPE_DECL for the class, not a
3930 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
3931 or one of its enclosing classes, and that type is a template,
3932 return the associated TEMPLATE_DECL. Otherwise, the original
3933 DECL is returned. */
3936 maybe_get_template_decl_from_type_decl (tree decl)
3938 return (decl != NULL_TREE
3939 && TREE_CODE (decl) == TYPE_DECL
3940 && DECL_ARTIFICIAL (decl)
3941 && CLASS_TYPE_P (TREE_TYPE (decl))
3942 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
3943 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
3946 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
3947 parameters, find the desired type.
3949 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
3950 (Actually ARGLIST may be either a TREE_LIST or a TREE_VEC. It will
3951 be a TREE_LIST if called directly from the parser, and a TREE_VEC
3954 IN_DECL, if non-NULL, is the template declaration we are trying to
3957 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
3958 the class we are looking up.
3960 Issue error and warning messages under control of COMPLAIN.
3962 If the template class is really a local class in a template
3963 function, then the FUNCTION_CONTEXT is the function in which it is
3964 being instantiated. */
3967 lookup_template_class (tree d1,
3972 tsubst_flags_t complain)
3974 tree template = NULL_TREE, parmlist;
3977 timevar_push (TV_NAME_LOOKUP);
3978 if (TREE_CODE (d1) == IDENTIFIER_NODE)
3980 if (IDENTIFIER_VALUE (d1)
3981 && DECL_TEMPLATE_TEMPLATE_PARM_P (IDENTIFIER_VALUE (d1)))
3982 template = IDENTIFIER_VALUE (d1);
3986 push_decl_namespace (context);
3987 template = lookup_name (d1, /*prefer_type=*/0);
3988 template = maybe_get_template_decl_from_type_decl (template);
3990 pop_decl_namespace ();
3993 context = DECL_CONTEXT (template);
3995 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
3997 tree type = TREE_TYPE (d1);
3999 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4000 an implicit typename for the second A. Deal with it. */
4001 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4002 type = TREE_TYPE (type);
4004 if (CLASSTYPE_TEMPLATE_INFO (type))
4006 template = CLASSTYPE_TI_TEMPLATE (type);
4007 d1 = DECL_NAME (template);
4010 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4011 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4013 template = TYPE_TI_TEMPLATE (d1);
4014 d1 = DECL_NAME (template);
4016 else if (TREE_CODE (d1) == TEMPLATE_DECL
4017 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4020 d1 = DECL_NAME (template);
4021 context = DECL_CONTEXT (template);
4024 /* With something like `template <class T> class X class X { ... };'
4025 we could end up with D1 having nothing but an IDENTIFIER_VALUE.
4026 We don't want to do that, but we have to deal with the situation,
4027 so let's give them some syntax errors to chew on instead of a
4028 crash. Alternatively D1 might not be a template type at all. */
4031 if (complain & tf_error)
4032 error ("`%T' is not a template", d1);
4033 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4036 if (TREE_CODE (template) != TEMPLATE_DECL
4037 /* If we're called from the parser, make sure it's a user visible
4039 || ((!arglist || TREE_CODE (arglist) == TREE_LIST)
4040 && !DECL_TEMPLATE_PARM_P (template)
4041 && !PRIMARY_TEMPLATE_P (template)))
4043 if (complain & tf_error)
4045 error ("non-template type `%T' used as a template", d1);
4047 cp_error_at ("for template declaration `%D'", in_decl);
4049 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4052 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4054 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4055 template arguments */
4060 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4062 /* Consider an example where a template template parameter declared as
4064 template <class T, class U = std::allocator<T> > class TT
4066 The template parameter level of T and U are one level larger than
4067 of TT. To proper process the default argument of U, say when an
4068 instantiation `TT<int>' is seen, we need to build the full
4069 arguments containing {int} as the innermost level. Outer levels,
4070 available when not appearing as default template argument, can be
4071 obtained from `current_template_args ()'.
4073 Suppose that TT is later substituted with std::vector. The above
4074 instantiation is `TT<int, std::allocator<T> >' with TT at
4075 level 1, and T at level 2, while the template arguments at level 1
4076 becomes {std::vector} and the inner level 2 is {int}. */
4078 if (current_template_parms)
4079 arglist = add_to_template_args (current_template_args (), arglist);
4081 arglist2 = coerce_template_parms (parmlist, arglist, template,
4082 complain, /*require_all_args=*/1);
4083 if (arglist2 == error_mark_node
4084 || (!uses_template_parms (arglist2)
4085 && check_instantiated_args (template, arglist2, complain)))
4086 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4088 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4089 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4093 tree template_type = TREE_TYPE (template);
4096 tree found = NULL_TREE;
4100 int is_partial_instantiation;
4102 gen_tmpl = most_general_template (template);
4103 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4104 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4105 arg_depth = TMPL_ARGS_DEPTH (arglist);
4107 if (arg_depth == 1 && parm_depth > 1)
4109 /* We've been given an incomplete set of template arguments.
4112 template <class T> struct S1 {
4113 template <class U> struct S2 {};
4114 template <class U> struct S2<U*> {};
4117 we will be called with an ARGLIST of `U*', but the
4118 TEMPLATE will be `template <class T> template
4119 <class U> struct S1<T>::S2'. We must fill in the missing
4122 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4124 arg_depth = TMPL_ARGS_DEPTH (arglist);
4127 /* Now we should have enough arguments. */
4128 my_friendly_assert (parm_depth == arg_depth, 0);
4130 /* From here on, we're only interested in the most general
4132 template = gen_tmpl;
4134 /* Calculate the BOUND_ARGS. These will be the args that are
4135 actually tsubst'd into the definition to create the
4139 /* We have multiple levels of arguments to coerce, at once. */
4141 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4143 tree bound_args = make_tree_vec (parm_depth);
4145 for (i = saved_depth,
4146 t = DECL_TEMPLATE_PARMS (template);
4147 i > 0 && t != NULL_TREE;
4148 --i, t = TREE_CHAIN (t))
4150 tree a = coerce_template_parms (TREE_VALUE (t),
4152 complain, /*require_all_args=*/1);
4154 /* Don't process further if one of the levels fails. */
4155 if (a == error_mark_node)
4157 /* Restore the ARGLIST to its full size. */
4158 TREE_VEC_LENGTH (arglist) = saved_depth;
4159 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4162 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4164 /* We temporarily reduce the length of the ARGLIST so
4165 that coerce_template_parms will see only the arguments
4166 corresponding to the template parameters it is
4168 TREE_VEC_LENGTH (arglist)--;
4171 /* Restore the ARGLIST to its full size. */
4172 TREE_VEC_LENGTH (arglist) = saved_depth;
4174 arglist = bound_args;
4178 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4179 INNERMOST_TEMPLATE_ARGS (arglist),
4181 complain, /*require_all_args=*/1);
4183 if (arglist == error_mark_node
4184 || (!uses_template_parms (INNERMOST_TEMPLATE_ARGS (arglist))
4185 && check_instantiated_args (template,
4186 INNERMOST_TEMPLATE_ARGS (arglist),
4188 /* We were unable to bind the arguments. */
4189 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4191 /* In the scope of a template class, explicit references to the
4192 template class refer to the type of the template, not any
4193 instantiation of it. For example, in:
4195 template <class T> class C { void f(C<T>); }
4197 the `C<T>' is just the same as `C'. Outside of the
4198 class, however, such a reference is an instantiation. */
4199 if (comp_template_args (TYPE_TI_ARGS (template_type),
4202 found = template_type;
4204 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4208 for (ctx = current_class_type;
4210 ctx = TYPE_CONTEXT (ctx))
4212 if (TREE_CODE (ctx) == NAMESPACE_DECL)
4214 if (same_type_p (ctx, template_type))
4218 /* We're not in the scope of the class, so the
4219 TEMPLATE_TYPE is not the type we want after all. */
4225 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4227 for (tp = &DECL_TEMPLATE_INSTANTIATIONS (template);
4229 tp = &TREE_CHAIN (*tp))
4230 if (comp_template_args (TREE_PURPOSE (*tp), arglist))
4234 /* Use the move-to-front heuristic to speed up future
4236 *tp = TREE_CHAIN (*tp);
4238 = DECL_TEMPLATE_INSTANTIATIONS (template);
4239 DECL_TEMPLATE_INSTANTIATIONS (template) = found;
4241 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, TREE_VALUE (found));
4244 /* This type is a "partial instantiation" if any of the template
4245 arguments still involve template parameters. Note that we set
4246 IS_PARTIAL_INSTANTIATION for partial specializations as
4248 is_partial_instantiation = uses_template_parms (arglist);
4250 if (!is_partial_instantiation
4251 && !PRIMARY_TEMPLATE_P (template)
4252 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4254 found = xref_tag_from_type (TREE_TYPE (template),
4255 DECL_NAME (template),
4257 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4260 context = tsubst (DECL_CONTEXT (template), arglist,
4263 context = global_namespace;
4265 /* Create the type. */
4266 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4268 if (!is_partial_instantiation)
4270 set_current_access_from_decl (TYPE_NAME (template_type));
4271 t = start_enum (TYPE_IDENTIFIER (template_type));
4274 /* We don't want to call start_enum for this type, since
4275 the values for the enumeration constants may involve
4276 template parameters. And, no one should be interested
4277 in the enumeration constants for such a type. */
4278 t = make_node (ENUMERAL_TYPE);
4282 t = make_aggr_type (TREE_CODE (template_type));
4283 CLASSTYPE_DECLARED_CLASS (t)
4284 = CLASSTYPE_DECLARED_CLASS (template_type);
4285 CLASSTYPE_GOT_SEMICOLON (t) = 1;
4286 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4287 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4289 /* A local class. Make sure the decl gets registered properly. */
4290 if (context == current_function_decl)
4291 pushtag (DECL_NAME (template), t, 0);
4294 /* If we called start_enum or pushtag above, this information
4295 will already be set up. */
4298 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4300 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4301 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4302 TYPE_STUB_DECL (t) = type_decl;
4303 DECL_SOURCE_LOCATION (type_decl)
4304 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4307 type_decl = TYPE_NAME (t);
4309 TREE_PRIVATE (type_decl)
4310 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4311 TREE_PROTECTED (type_decl)
4312 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4314 /* Set up the template information. We have to figure out which
4315 template is the immediate parent if this is a full
4317 if (parm_depth == 1 || is_partial_instantiation
4318 || !PRIMARY_TEMPLATE_P (template))
4319 /* This case is easy; there are no member templates involved. */
4323 /* This is a full instantiation of a member template. Look
4324 for a partial instantiation of which this is an instance. */
4326 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4327 found; found = TREE_CHAIN (found))
4330 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4332 /* We only want partial instantiations, here, not
4333 specializations or full instantiations. */
4334 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4335 || !uses_template_parms (TREE_VALUE (found)))
4338 /* Temporarily reduce by one the number of levels in the
4339 ARGLIST and in FOUND so as to avoid comparing the
4340 last set of arguments. */
4341 TREE_VEC_LENGTH (arglist)--;
4342 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4344 /* See if the arguments match. If they do, then TMPL is
4345 the partial instantiation we want. */
4346 success = comp_template_args (TREE_PURPOSE (found), arglist);
4348 /* Restore the argument vectors to their full size. */
4349 TREE_VEC_LENGTH (arglist)++;
4350 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4361 /* There was no partial instantiation. This happens
4362 where C<T> is a member template of A<T> and it's used
4365 template <typename T> struct B { A<T>::C<int> m; };
4368 Create the partial instantiation.
4370 TREE_VEC_LENGTH (arglist)--;
4371 found = tsubst (template, arglist, complain, NULL_TREE);
4372 TREE_VEC_LENGTH (arglist)++;
4376 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4377 DECL_TEMPLATE_INSTANTIATIONS (template)
4378 = tree_cons (arglist, t,
4379 DECL_TEMPLATE_INSTANTIATIONS (template));
4381 if (TREE_CODE (t) == ENUMERAL_TYPE
4382 && !is_partial_instantiation)
4383 /* Now that the type has been registered on the instantiations
4384 list, we set up the enumerators. Because the enumeration
4385 constants may involve the enumeration type itself, we make
4386 sure to register the type first, and then create the
4387 constants. That way, doing tsubst_expr for the enumeration
4388 constants won't result in recursive calls here; we'll find
4389 the instantiation and exit above. */
4390 tsubst_enum (template_type, t, arglist);
4392 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4394 if (TREE_CODE (t) != ENUMERAL_TYPE)
4395 DECL_NAME (type_decl) = classtype_mangled_name (t);
4396 if (!is_partial_instantiation)
4398 /* For backwards compatibility; code that uses
4399 -fexternal-templates expects looking up a template to
4400 instantiate it. I think DDD still relies on this.
4401 (jason 8/20/1998) */
4402 if (TREE_CODE (t) != ENUMERAL_TYPE
4403 && flag_external_templates
4404 && CLASSTYPE_INTERFACE_KNOWN (TREE_TYPE (template))
4405 && ! CLASSTYPE_INTERFACE_ONLY (TREE_TYPE (template)))
4406 add_pending_template (t);
4409 /* If the type makes use of template parameters, the
4410 code that generates debugging information will crash. */
4411 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4413 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4415 timevar_pop (TV_NAME_LOOKUP);
4425 /* Called from for_each_template_parm via walk_tree. */
4428 for_each_template_parm_r (tree* tp, int* walk_subtrees, void* d)
4431 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4432 tree_fn_t fn = pfd->fn;
4433 void *data = pfd->data;
4436 /* If we have already visited this tree, there's no need to walk
4437 subtrees. Otherwise, add it to the visited table. */
4438 slot = htab_find_slot (pfd->visited, *tp, INSERT);
4447 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4448 return error_mark_node;
4450 switch (TREE_CODE (t))
4453 if (TYPE_PTRMEMFUNC_P (t))
4459 if (!TYPE_TEMPLATE_INFO (t))
4461 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4462 fn, data, pfd->visited))
4463 return error_mark_node;
4467 /* Since we're not going to walk subtrees, we have to do this
4469 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4471 return error_mark_node;
4475 /* Check the return type. */
4476 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4477 return error_mark_node;
4479 /* Check the parameter types. Since default arguments are not
4480 instantiated until they are needed, the TYPE_ARG_TYPES may
4481 contain expressions that involve template parameters. But,
4482 no-one should be looking at them yet. And, once they're
4483 instantiated, they don't contain template parameters, so
4484 there's no point in looking at them then, either. */
4488 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4489 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4491 return error_mark_node;
4493 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4494 want walk_tree walking into them itself. */
4500 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4502 return error_mark_node;
4507 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4508 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4510 return error_mark_node;
4515 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4516 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4518 return error_mark_node;
4519 if (DECL_CONTEXT (t)
4520 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4522 return error_mark_node;
4525 case BOUND_TEMPLATE_TEMPLATE_PARM:
4526 /* Record template parameters such as `T' inside `TT<T>'. */
4527 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4528 return error_mark_node;
4531 case TEMPLATE_TEMPLATE_PARM:
4532 case TEMPLATE_TYPE_PARM:
4533 case TEMPLATE_PARM_INDEX:
4534 if (fn && (*fn)(t, data))
4535 return error_mark_node;
4537 return error_mark_node;
4541 /* A template template parameter is encountered */
4542 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4543 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4544 return error_mark_node;
4546 /* Already substituted template template parameter */
4552 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4553 data, pfd->visited))
4554 return error_mark_node;
4558 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4559 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4560 (TREE_TYPE (t)), fn, data,
4562 return error_mark_node;
4567 /* If there's no type, then this thing must be some expression
4568 involving template parameters. */
4569 if (!fn && !TREE_TYPE (t))
4570 return error_mark_node;
4575 case REINTERPRET_CAST_EXPR:
4576 case CONST_CAST_EXPR:
4577 case STATIC_CAST_EXPR:
4578 case DYNAMIC_CAST_EXPR:
4583 case PSEUDO_DTOR_EXPR:
4585 return error_mark_node;
4589 /* If we do not handle this case specially, we end up walking
4590 the BINFO hierarchy, which is circular, and therefore
4591 confuses walk_tree. */
4593 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4595 return error_mark_node;
4602 /* We didn't find any template parameters we liked. */
4606 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4607 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4608 call FN with the parameter and the DATA.
4609 If FN returns nonzero, the iteration is terminated, and
4610 for_each_template_parm returns 1. Otherwise, the iteration
4611 continues. If FN never returns a nonzero value, the value
4612 returned by for_each_template_parm is 0. If FN is NULL, it is
4613 considered to be the function which always returns 1. */
4616 for_each_template_parm (tree t, tree_fn_t fn, void* data, htab_t visited)
4618 struct pair_fn_data pfd;
4625 /* Walk the tree. (Conceptually, we would like to walk without
4626 duplicates, but for_each_template_parm_r recursively calls
4627 for_each_template_parm, so we would need to reorganize a fair
4628 bit to use walk_tree_without_duplicates, so we keep our own
4631 pfd.visited = visited;
4633 pfd.visited = htab_create (37, htab_hash_pointer, htab_eq_pointer,
4635 result = walk_tree (&t,
4636 for_each_template_parm_r,
4642 htab_delete (pfd.visited);
4648 uses_template_parms (tree t)
4650 return for_each_template_parm (t, 0, 0, NULL);
4653 static int tinst_depth;
4654 extern int max_tinst_depth;
4655 #ifdef GATHER_STATISTICS
4658 static int tinst_level_tick;
4659 static int last_template_error_tick;
4661 /* We're starting to instantiate D; record the template instantiation context
4662 for diagnostics and to restore it later. */
4665 push_tinst_level (tree d)
4669 if (tinst_depth >= max_tinst_depth)
4671 /* If the instantiation in question still has unbound template parms,
4672 we don't really care if we can't instantiate it, so just return.
4673 This happens with base instantiation for implicit `typename'. */
4674 if (uses_template_parms (d))
4677 last_template_error_tick = tinst_level_tick;
4678 error ("template instantiation depth exceeds maximum of %d (use -ftemplate-depth-NN to increase the maximum) instantiating `%D'",
4679 max_tinst_depth, d);
4681 print_instantiation_context ();
4686 new = build_expr_wfl (d, input_filename, input_line, 0);
4687 TREE_CHAIN (new) = current_tinst_level;
4688 current_tinst_level = new;
4691 #ifdef GATHER_STATISTICS
4692 if (tinst_depth > depth_reached)
4693 depth_reached = tinst_depth;
4700 /* We're done instantiating this template; return to the instantiation
4704 pop_tinst_level (void)
4706 tree old = current_tinst_level;
4708 /* Restore the filename and line number stashed away when we started
4709 this instantiation. */
4710 input_line = TINST_LINE (old);
4711 input_filename = TINST_FILE (old);
4712 extract_interface_info ();
4714 current_tinst_level = TREE_CHAIN (old);
4719 /* We're instantiating a deferred template; restore the template
4720 instantiation context in which the instantiation was requested, which
4721 is one step out from LEVEL. */
4724 reopen_tinst_level (tree level)
4729 for (t = level; t; t = TREE_CHAIN (t))
4732 current_tinst_level = level;
4736 /* Return the outermost template instantiation context, for use with
4737 -falt-external-templates. */
4740 tinst_for_decl (void)
4742 tree p = current_tinst_level;
4745 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
4750 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4751 vector of template arguments, as for tsubst.
4753 Returns an appropriate tsubst'd friend declaration. */
4756 tsubst_friend_function (tree decl, tree args)
4759 location_t saved_loc = input_location;
4761 input_location = DECL_SOURCE_LOCATION (decl);
4763 if (TREE_CODE (decl) == FUNCTION_DECL
4764 && DECL_TEMPLATE_INSTANTIATION (decl)
4765 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
4766 /* This was a friend declared with an explicit template
4767 argument list, e.g.:
4771 to indicate that f was a template instantiation, not a new
4772 function declaration. Now, we have to figure out what
4773 instantiation of what template. */
4775 tree template_id, arglist, fns;
4778 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
4780 /* Friend functions are looked up in the containing namespace scope.
4781 We must enter that scope, to avoid finding member functions of the
4782 current cless with same name. */
4783 push_nested_namespace (ns);
4784 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
4785 tf_error | tf_warning, NULL_TREE);
4786 pop_nested_namespace (ns);
4787 arglist = tsubst (DECL_TI_ARGS (decl), args,
4788 tf_error | tf_warning, NULL_TREE);
4789 template_id = lookup_template_function (fns, arglist);
4791 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
4792 tmpl = determine_specialization (template_id, new_friend,
4794 /*need_member_template=*/0);
4795 new_friend = instantiate_template (tmpl, new_args, tf_error);
4799 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
4801 /* The NEW_FRIEND will look like an instantiation, to the
4802 compiler, but is not an instantiation from the point of view of
4803 the language. For example, we might have had:
4805 template <class T> struct S {
4806 template <class U> friend void f(T, U);
4809 Then, in S<int>, template <class U> void f(int, U) is not an
4810 instantiation of anything. */
4811 DECL_USE_TEMPLATE (new_friend) = 0;
4812 if (TREE_CODE (decl) == TEMPLATE_DECL)
4814 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
4815 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
4816 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
4819 /* The mangled name for the NEW_FRIEND is incorrect. The function
4820 is not a template instantiation and should not be mangled like
4821 one. Therefore, we forget the mangling here; we'll recompute it
4822 later if we need it. */
4823 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
4825 SET_DECL_RTL (new_friend, NULL_RTX);
4826 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
4829 if (DECL_NAMESPACE_SCOPE_P (new_friend))
4832 tree new_friend_template_info;
4833 tree new_friend_result_template_info;
4835 int new_friend_is_defn;
4837 /* We must save some information from NEW_FRIEND before calling
4838 duplicate decls since that function will free NEW_FRIEND if
4840 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
4841 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
4843 /* This declaration is a `primary' template. */
4844 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
4847 = DECL_INITIAL (DECL_TEMPLATE_RESULT (new_friend)) != NULL_TREE;
4848 new_friend_result_template_info
4849 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
4853 new_friend_is_defn = DECL_INITIAL (new_friend) != NULL_TREE;
4854 new_friend_result_template_info = NULL_TREE;
4857 /* Inside pushdecl_namespace_level, we will push into the
4858 current namespace. However, the friend function should go
4859 into the namespace of the template. */
4860 ns = decl_namespace_context (new_friend);
4861 push_nested_namespace (ns);
4862 old_decl = pushdecl_namespace_level (new_friend);
4863 pop_nested_namespace (ns);
4865 if (old_decl != new_friend)
4867 /* This new friend declaration matched an existing
4868 declaration. For example, given:
4870 template <class T> void f(T);
4871 template <class U> class C {
4872 template <class T> friend void f(T) {}
4875 the friend declaration actually provides the definition
4876 of `f', once C has been instantiated for some type. So,
4877 old_decl will be the out-of-class template declaration,
4878 while new_friend is the in-class definition.
4880 But, if `f' was called before this point, the
4881 instantiation of `f' will have DECL_TI_ARGS corresponding
4882 to `T' but not to `U', references to which might appear
4883 in the definition of `f'. Previously, the most general
4884 template for an instantiation of `f' was the out-of-class
4885 version; now it is the in-class version. Therefore, we
4886 run through all specialization of `f', adding to their
4887 DECL_TI_ARGS appropriately. In particular, they need a
4888 new set of outer arguments, corresponding to the
4889 arguments for this class instantiation.
4891 The same situation can arise with something like this:
4894 template <class T> class C {
4898 when `C<int>' is instantiated. Now, `f(int)' is defined
4901 if (!new_friend_is_defn)
4902 /* On the other hand, if the in-class declaration does
4903 *not* provide a definition, then we don't want to alter
4904 existing definitions. We can just leave everything
4909 /* Overwrite whatever template info was there before, if
4910 any, with the new template information pertaining to
4912 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
4914 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
4919 t = most_general_template (old_decl);
4920 for (spec = DECL_TEMPLATE_SPECIALIZATIONS (t);
4922 spec = TREE_CHAIN (spec))
4923 if (TREE_VALUE (spec) == new_friend)
4924 TREE_VALUE (spec) = old_decl;
4929 tree new_friend_args;
4931 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
4932 = new_friend_result_template_info;
4934 new_friend_args = TI_ARGS (new_friend_template_info);
4935 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
4939 tree spec = TREE_VALUE (t);
4942 = add_outermost_template_args (new_friend_args,
4943 DECL_TI_ARGS (spec));
4946 /* Now, since specializations are always supposed to
4947 hang off of the most general template, we must move
4949 t = most_general_template (old_decl);
4952 DECL_TEMPLATE_SPECIALIZATIONS (t)
4953 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
4954 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
4955 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
4960 /* The information from NEW_FRIEND has been merged into OLD_DECL
4961 by duplicate_decls. */
4962 new_friend = old_decl;
4965 else if (COMPLETE_TYPE_P (DECL_CONTEXT (new_friend)))
4967 /* Check to see that the declaration is really present, and,
4968 possibly obtain an improved declaration. */
4969 tree fn = check_classfn (DECL_CONTEXT (new_friend),
4977 input_location = saved_loc;
4981 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
4982 template arguments, as for tsubst.
4984 Returns an appropriate tsubst'd friend type or error_mark_node on
4988 tsubst_friend_class (tree friend_tmpl, tree args)
4994 context = DECL_CONTEXT (friend_tmpl);
4998 if (TREE_CODE (context) == NAMESPACE_DECL)
4999 push_nested_namespace (context);
5001 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5004 /* First, we look for a class template. */
5005 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5007 /* But, if we don't find one, it might be because we're in a
5008 situation like this:
5016 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5017 for `S<int>', not the TEMPLATE_DECL. */
5018 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5020 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5021 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5024 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5026 /* The friend template has already been declared. Just
5027 check to see that the declarations match, and install any new
5028 default parameters. We must tsubst the default parameters,
5029 of course. We only need the innermost template parameters
5030 because that is all that redeclare_class_template will look
5032 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5033 > TMPL_ARGS_DEPTH (args))
5036 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5037 args, tf_error | tf_warning);
5038 redeclare_class_template (TREE_TYPE (tmpl), parms);
5041 friend_type = TREE_TYPE (tmpl);
5045 /* The friend template has not already been declared. In this
5046 case, the instantiation of the template class will cause the
5047 injection of this template into the global scope. */
5048 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5050 /* The new TMPL is not an instantiation of anything, so we
5051 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5052 the new type because that is supposed to be the corresponding
5053 template decl, i.e., TMPL. */
5054 DECL_USE_TEMPLATE (tmpl) = 0;
5055 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5056 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5058 /* Inject this template into the global scope. */
5059 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5064 if (TREE_CODE (context) == NAMESPACE_DECL)
5065 pop_nested_namespace (context);
5067 pop_nested_class ();
5073 /* Returns zero if TYPE cannot be completed later due to circularity.
5074 Otherwise returns one. */
5077 can_complete_type_without_circularity (tree type)
5079 if (type == NULL_TREE || type == error_mark_node)
5081 else if (COMPLETE_TYPE_P (type))
5083 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5084 return can_complete_type_without_circularity (TREE_TYPE (type));
5085 else if (CLASS_TYPE_P (type) && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5092 instantiate_class_template (tree type)
5094 tree template, args, pattern, t, member;
5098 if (type == error_mark_node)
5099 return error_mark_node;
5101 if (TYPE_BEING_DEFINED (type)
5102 || COMPLETE_TYPE_P (type)
5103 || dependent_type_p (type))
5106 /* Figure out which template is being instantiated. */
5107 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5108 my_friendly_assert (TREE_CODE (template) == TEMPLATE_DECL, 279);
5110 /* Figure out which arguments are being used to do the
5112 args = CLASSTYPE_TI_ARGS (type);
5114 /* Determine what specialization of the original template to
5116 t = most_specialized_class (template, args);
5117 if (t == error_mark_node)
5119 const char *str = "candidates are:";
5120 error ("ambiguous class template instantiation for `%#T'", type);
5121 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5124 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5127 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5131 TYPE_BEING_DEFINED (type) = 1;
5132 return error_mark_node;
5136 pattern = TREE_TYPE (t);
5138 pattern = TREE_TYPE (template);
5140 /* If the template we're instantiating is incomplete, then clearly
5141 there's nothing we can do. */
5142 if (!COMPLETE_TYPE_P (pattern))
5145 /* If we've recursively instantiated too many templates, stop. */
5146 if (! push_tinst_level (type))
5149 /* Now we're really doing the instantiation. Mark the type as in
5150 the process of being defined. */
5151 TYPE_BEING_DEFINED (type) = 1;
5153 /* We may be in the middle of deferred access check. Disable
5155 push_deferring_access_checks (dk_no_deferred);
5157 maybe_push_to_top_level (uses_template_parms (type));
5161 /* This TYPE is actually an instantiation of a partial
5162 specialization. We replace the innermost set of ARGS with
5163 the arguments appropriate for substitution. For example,
5166 template <class T> struct S {};
5167 template <class T> struct S<T*> {};
5169 and supposing that we are instantiating S<int*>, ARGS will
5170 present be {int*} but we need {int}. */
5172 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5175 /* If there were multiple levels in ARGS, replacing the
5176 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5177 want, so we make a copy first. */
5178 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5180 args = copy_node (args);
5181 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5187 if (flag_external_templates)
5189 if (flag_alt_external_templates)
5191 CLASSTYPE_INTERFACE_ONLY (type) = interface_only;
5192 SET_CLASSTYPE_INTERFACE_UNKNOWN_X (type, interface_unknown);
5196 CLASSTYPE_INTERFACE_ONLY (type) = CLASSTYPE_INTERFACE_ONLY (pattern);
5197 SET_CLASSTYPE_INTERFACE_UNKNOWN_X
5198 (type, CLASSTYPE_INTERFACE_UNKNOWN (pattern));
5203 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5206 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5207 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5208 TYPE_OVERLOADS_CALL_EXPR (type) = TYPE_OVERLOADS_CALL_EXPR (pattern);
5209 TYPE_OVERLOADS_ARRAY_REF (type) = TYPE_OVERLOADS_ARRAY_REF (pattern);
5210 TYPE_OVERLOADS_ARROW (type) = TYPE_OVERLOADS_ARROW (pattern);
5211 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5212 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5213 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5214 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5215 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5216 TYPE_HAS_ABSTRACT_ASSIGN_REF (type) = TYPE_HAS_ABSTRACT_ASSIGN_REF (pattern);
5217 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5218 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5219 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5220 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5221 TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
5222 = TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (pattern);
5223 TYPE_USES_MULTIPLE_INHERITANCE (type)
5224 = TYPE_USES_MULTIPLE_INHERITANCE (pattern);
5225 TYPE_USES_VIRTUAL_BASECLASSES (type)
5226 = TYPE_USES_VIRTUAL_BASECLASSES (pattern);
5227 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5228 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5229 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5230 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5231 if (ANON_AGGR_TYPE_P (pattern))
5232 SET_ANON_AGGR_TYPE_P (type);
5234 pbinfo = TYPE_BINFO (pattern);
5236 if (BINFO_BASETYPES (pbinfo))
5238 tree base_list = NULL_TREE;
5239 tree pbases = BINFO_BASETYPES (pbinfo);
5240 tree paccesses = BINFO_BASEACCESSES (pbinfo);
5243 /* Substitute into each of the bases to determine the actual
5245 for (i = 0; i < TREE_VEC_LENGTH (pbases); ++i)
5251 pbase = TREE_VEC_ELT (pbases, i);
5252 access = TREE_VEC_ELT (paccesses, i);
5254 /* Substitute to figure out the base class. */
5255 base = tsubst (BINFO_TYPE (pbase), args, tf_error, NULL_TREE);
5256 if (base == error_mark_node)
5259 base_list = tree_cons (access, base, base_list);
5260 TREE_VIA_VIRTUAL (base_list) = TREE_VIA_VIRTUAL (pbase);
5263 /* The list is now in reverse order; correct that. */
5264 base_list = nreverse (base_list);
5266 /* Now call xref_basetypes to set up all the base-class
5268 xref_basetypes (type, base_list);
5271 /* Now that our base classes are set up, enter the scope of the
5272 class, so that name lookups into base classes, etc. will work
5273 correctly. This is precisely analogous to what we do in
5274 begin_class_definition when defining an ordinary non-template
5276 pushclass (type, true);
5278 /* Now members are processed in the order of declaration. */
5279 for (member = CLASSTYPE_DECL_LIST (pattern); member; member = TREE_CHAIN (member))
5281 tree t = TREE_VALUE (member);
5283 if (TREE_PURPOSE (member))
5287 /* Build new CLASSTYPE_NESTED_UTDS. */
5290 tree name = TYPE_IDENTIFIER (tag);
5293 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5294 my_friendly_assert (newtag != error_mark_node, 20010206);
5295 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5297 if (TYPE_LANG_SPECIFIC (tag) && CLASSTYPE_IS_TEMPLATE (tag))
5298 /* Unfortunately, lookup_template_class sets
5299 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5300 instantiation (i.e., for the type of a member template
5301 class nested within a template class.) This behavior is
5302 required for maybe_process_partial_specialization to work
5303 correctly, but is not accurate in this case; the TAG is not
5304 an instantiation of anything. (The corresponding
5305 TEMPLATE_DECL is an instantiation, but the TYPE is not.) */
5306 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5308 /* Now, we call pushtag to put this NEWTAG into the scope of
5309 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5310 pushtag calling push_template_decl. We don't have to do
5311 this for enums because it will already have been done in
5314 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5315 pushtag (name, newtag, /*globalize=*/0);
5318 else if (TREE_CODE (t) == FUNCTION_DECL
5319 || DECL_FUNCTION_TEMPLATE_P (t))
5321 /* Build new TYPE_METHODS. */
5323 tree r = tsubst (t, args, tf_error, NULL_TREE);
5324 set_current_access_from_decl (r);
5325 grok_special_member_properties (r);
5326 finish_member_declaration (r);
5330 /* Build new TYPE_FIELDS. */
5332 if (TREE_CODE (t) != CONST_DECL)
5336 /* The the file and line for this declaration, to
5337 assist in error message reporting. Since we
5338 called push_tinst_level above, we don't need to
5340 input_location = DECL_SOURCE_LOCATION (t);
5342 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5343 if (TREE_CODE (r) == VAR_DECL)
5347 if (DECL_INITIALIZED_IN_CLASS_P (r))
5348 init = tsubst_expr (DECL_INITIAL (t), args,
5349 tf_error | tf_warning, NULL_TREE);
5353 finish_static_data_member_decl (r, init,
5354 /*asmspec_tree=*/NULL_TREE,
5357 if (DECL_INITIALIZED_IN_CLASS_P (r))
5358 check_static_variable_definition (r, TREE_TYPE (r));
5360 else if (TREE_CODE (r) == FIELD_DECL)
5362 /* Determine whether R has a valid type and can be
5363 completed later. If R is invalid, then it is
5364 replaced by error_mark_node so that it will not be
5365 added to TYPE_FIELDS. */
5366 tree rtype = TREE_TYPE (r);
5367 if (can_complete_type_without_circularity (rtype))
5368 complete_type (rtype);
5370 if (!COMPLETE_TYPE_P (rtype))
5372 cxx_incomplete_type_error (r, rtype);
5373 r = error_mark_node;
5377 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5378 such a thing will already have been added to the field
5379 list by tsubst_enum in finish_member_declaration in the
5380 CLASSTYPE_NESTED_UTDS case above. */
5381 if (!(TREE_CODE (r) == TYPE_DECL
5382 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5383 && DECL_ARTIFICIAL (r)))
5385 set_current_access_from_decl (r);
5386 finish_member_declaration (r);
5393 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5395 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5397 tree friend_type = t;
5398 tree new_friend_type;
5400 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5401 new_friend_type = tsubst_friend_class (friend_type, args);
5402 else if (uses_template_parms (friend_type))
5403 new_friend_type = tsubst (friend_type, args,
5404 tf_error | tf_warning, NULL_TREE);
5405 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5406 new_friend_type = friend_type;
5409 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5411 /* The call to xref_tag_from_type does injection for friend
5413 push_nested_namespace (ns);
5415 xref_tag_from_type (friend_type, NULL_TREE, 1);
5416 pop_nested_namespace (ns);
5419 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5420 /* Trick make_friend_class into realizing that the friend
5421 we're adding is a template, not an ordinary class. It's
5422 important that we use make_friend_class since it will
5423 perform some error-checking and output cross-reference
5425 ++processing_template_decl;
5427 if (new_friend_type != error_mark_node)
5428 make_friend_class (type, new_friend_type);
5430 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5431 --processing_template_decl;
5434 /* Build new DECL_FRIENDLIST. */
5435 add_friend (type, tsubst_friend_function (t, args));
5439 /* Set the file and line number information to whatever is given for
5440 the class itself. This puts error messages involving generated
5441 implicit functions at a predictable point, and the same point
5442 that would be used for non-template classes. */
5443 typedecl = TYPE_MAIN_DECL (type);
5444 input_location = DECL_SOURCE_LOCATION (typedecl);
5446 unreverse_member_declarations (type);
5447 finish_struct_1 (type);
5448 CLASSTYPE_GOT_SEMICOLON (type) = 1;
5450 /* Clear this now so repo_template_used is happy. */
5451 TYPE_BEING_DEFINED (type) = 0;
5452 repo_template_used (type);
5454 /* Now that the class is complete, instantiate default arguments for
5455 any member functions. We don't do this earlier because the
5456 default arguments may reference members of the class. */
5457 if (!PRIMARY_TEMPLATE_P (template))
5458 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5459 if (TREE_CODE (t) == FUNCTION_DECL
5460 /* Implicitly generated member functions will not have template
5461 information; they are not instantiations, but instead are
5462 created "fresh" for each instantiation. */
5463 && DECL_TEMPLATE_INFO (t))
5464 tsubst_default_arguments (t);
5467 pop_from_top_level ();
5468 pop_deferring_access_checks ();
5471 if (TYPE_CONTAINS_VPTR_P (type))
5472 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5478 list_eq (tree t1, tree t2)
5480 if (t1 == NULL_TREE)
5481 return t2 == NULL_TREE;
5482 if (t2 == NULL_TREE)
5484 /* Don't care if one declares its arg const and the other doesn't -- the
5485 main variant of the arg type is all that matters. */
5486 if (TYPE_MAIN_VARIANT (TREE_VALUE (t1))
5487 != TYPE_MAIN_VARIANT (TREE_VALUE (t2)))
5489 return list_eq (TREE_CHAIN (t1), TREE_CHAIN (t2));
5492 /* If arg is a non-type template parameter that does not depend on template
5493 arguments, fold it like we weren't in the body of a template. */
5496 maybe_fold_nontype_arg (tree arg)
5498 if (arg && !TYPE_P (arg) && !uses_template_parms (arg))
5500 /* Sometimes, one of the args was an expression involving a
5501 template constant parameter, like N - 1. Now that we've
5502 tsubst'd, we might have something like 2 - 1. This will
5503 confuse lookup_template_class, so we do constant folding
5504 here. We have to unset processing_template_decl, to fool
5505 tsubst_copy_and_build() into building an actual tree. */
5507 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5508 as simple as it's going to get, and trying to reprocess
5509 the trees will break. */
5510 if (!TREE_TYPE (arg))
5512 int saved_processing_template_decl = processing_template_decl;
5513 processing_template_decl = 0;
5514 arg = tsubst_copy_and_build (arg,
5517 /*in_decl=*/NULL_TREE,
5518 /*function_p=*/false);
5519 processing_template_decl = saved_processing_template_decl;
5527 /* Apply maybe_fold_nontype_arg on a list or vector of args. */
5530 maybe_fold_nontype_args (tree targs)
5534 else if (TREE_CODE (targs) == TREE_LIST)
5537 for (chain = targs; chain; chain = TREE_CHAIN (chain))
5538 TREE_VALUE (chain) = maybe_fold_nontype_arg (TREE_VALUE (chain));
5543 for (i = 0; i < TREE_VEC_LENGTH (targs); ++i)
5544 TREE_VEC_ELT (targs, i)
5545 = maybe_fold_nontype_arg (TREE_VEC_ELT (targs, i));
5549 /* Substitute ARGS into the vector of template arguments T. */
5552 tsubst_template_arg_vector (tree t, tree args, tsubst_flags_t complain)
5554 int len = TREE_VEC_LENGTH (t), need_new = 0, i;
5555 tree *elts = (tree *) alloca (len * sizeof (tree));
5557 memset ((char *) elts, 0, len * sizeof (tree));
5559 for (i = 0; i < len; i++)
5561 if (TREE_VEC_ELT (t, i) != NULL_TREE
5562 && TREE_CODE (TREE_VEC_ELT (t, i)) == TREE_VEC)
5563 elts[i] = tsubst_template_arg_vector (TREE_VEC_ELT (t, i),
5566 elts[i] = maybe_fold_nontype_arg
5567 (tsubst_expr (TREE_VEC_ELT (t, i), args, complain,
5570 if (elts[i] == error_mark_node)
5571 return error_mark_node;
5573 if (elts[i] != TREE_VEC_ELT (t, i))
5580 t = make_tree_vec (len);
5581 for (i = 0; i < len; i++)
5582 TREE_VEC_ELT (t, i) = elts[i];
5587 /* Return the result of substituting ARGS into the template parameters
5588 given by PARMS. If there are m levels of ARGS and m + n levels of
5589 PARMS, then the result will contain n levels of PARMS. For
5590 example, if PARMS is `template <class T> template <class U>
5591 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5592 result will be `template <int*, double, class V>'. */
5595 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5600 for (new_parms = &r;
5601 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5602 new_parms = &(TREE_CHAIN (*new_parms)),
5603 parms = TREE_CHAIN (parms))
5606 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5609 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5611 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5612 tree default_value = TREE_PURPOSE (tuple);
5613 tree parm_decl = TREE_VALUE (tuple);
5615 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5616 default_value = tsubst_expr (default_value, args,
5617 complain, NULL_TREE);
5618 tuple = build_tree_list (maybe_fold_nontype_arg (default_value),
5620 TREE_VEC_ELT (new_vec, i) = tuple;
5624 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
5625 - TMPL_ARGS_DEPTH (args)),
5626 new_vec, NULL_TREE);
5632 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5633 type T. If T is not an aggregate or enumeration type, it is
5634 handled as if by tsubst. IN_DECL is as for tsubst. If
5635 ENTERING_SCOPE is nonzero, T is the context for a template which
5636 we are presently tsubst'ing. Return the substituted value. */
5639 tsubst_aggr_type (tree t,
5641 tsubst_flags_t complain,
5648 switch (TREE_CODE (t))
5651 if (TYPE_PTRMEMFUNC_P (t))
5652 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
5654 /* else fall through */
5657 if (TYPE_TEMPLATE_INFO (t))
5663 /* First, determine the context for the type we are looking
5665 if (TYPE_CONTEXT (t) != NULL_TREE)
5666 context = tsubst_aggr_type (TYPE_CONTEXT (t), args,
5668 in_decl, /*entering_scope=*/1);
5670 context = NULL_TREE;
5672 /* Then, figure out what arguments are appropriate for the
5673 type we are trying to find. For example, given:
5675 template <class T> struct S;
5676 template <class T, class U> void f(T, U) { S<U> su; }
5678 and supposing that we are instantiating f<int, double>,
5679 then our ARGS will be {int, double}, but, when looking up
5680 S we only want {double}. */
5681 argvec = tsubst_template_arg_vector (TYPE_TI_ARGS (t), args,
5683 if (argvec == error_mark_node)
5684 return error_mark_node;
5686 r = lookup_template_class (t, argvec, in_decl, context,
5687 entering_scope, complain);
5689 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
5692 /* This is not a template type, so there's nothing to do. */
5696 return tsubst (t, args, complain, in_decl);
5700 /* Substitute into the default argument ARG (a default argument for
5701 FN), which has the indicated TYPE. */
5704 tsubst_default_argument (tree fn, tree type, tree arg)
5706 /* This default argument came from a template. Instantiate the
5707 default argument here, not in tsubst. In the case of
5716 we must be careful to do name lookup in the scope of S<T>,
5717 rather than in the current class.
5719 ??? current_class_type affects a lot more than name lookup. This is
5720 very fragile. Fortunately, it will go away when we do 2-phase name
5721 binding properly. */
5723 /* FN is already the desired FUNCTION_DECL. */
5724 push_access_scope (fn);
5726 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
5727 tf_error | tf_warning, NULL_TREE);
5729 pop_access_scope (fn);
5731 /* Make sure the default argument is reasonable. */
5732 arg = check_default_argument (type, arg);
5737 /* Substitute into all the default arguments for FN. */
5740 tsubst_default_arguments (tree fn)
5745 tmpl_args = DECL_TI_ARGS (fn);
5747 /* If this function is not yet instantiated, we certainly don't need
5748 its default arguments. */
5749 if (uses_template_parms (tmpl_args))
5752 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
5754 arg = TREE_CHAIN (arg))
5755 if (TREE_PURPOSE (arg))
5756 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
5758 TREE_PURPOSE (arg));
5761 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
5762 (already computed) substitution of ARGS into TREE_TYPE (T), if
5763 appropriate. Return the result of the substitution. Issue error
5764 and warning messages under control of COMPLAIN. */
5767 tsubst_decl (tree t, tree args, tree type, tsubst_flags_t complain)
5769 location_t saved_loc;
5773 /* Set the filename and linenumber to improve error-reporting. */
5774 saved_loc = input_location;
5775 input_location = DECL_SOURCE_LOCATION (t);
5777 switch (TREE_CODE (t))
5781 /* We can get here when processing a member template function
5782 of a template class. */
5783 tree decl = DECL_TEMPLATE_RESULT (t);
5785 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
5787 if (!is_template_template_parm)
5789 /* We might already have an instance of this template.
5790 The ARGS are for the surrounding class type, so the
5791 full args contain the tsubst'd args for the context,
5792 plus the innermost args from the template decl. */
5793 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
5794 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
5795 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
5798 full_args = tsubst_template_arg_vector (tmpl_args, args,
5801 /* tsubst_template_arg_vector doesn't copy the vector if
5802 nothing changed. But, *something* should have
5804 my_friendly_assert (full_args != tmpl_args, 0);
5806 spec = retrieve_specialization (t, full_args);
5807 if (spec != NULL_TREE)
5814 /* Make a new template decl. It will be similar to the
5815 original, but will record the current template arguments.
5816 We also create a new function declaration, which is just
5817 like the old one, but points to this new template, rather
5818 than the old one. */
5820 my_friendly_assert (DECL_LANG_SPECIFIC (r) != 0, 0);
5821 TREE_CHAIN (r) = NULL_TREE;
5823 if (is_template_template_parm)
5825 tree new_decl = tsubst (decl, args, complain, in_decl);
5826 DECL_TEMPLATE_RESULT (r) = new_decl;
5827 TREE_TYPE (r) = TREE_TYPE (new_decl);
5832 = tsubst_aggr_type (DECL_CONTEXT (t), args,
5834 /*entering_scope=*/1);
5835 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
5837 if (TREE_CODE (decl) == TYPE_DECL)
5839 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
5840 TREE_TYPE (r) = new_type;
5841 CLASSTYPE_TI_TEMPLATE (new_type) = r;
5842 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
5843 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
5847 tree new_decl = tsubst (decl, args, complain, in_decl);
5849 DECL_TEMPLATE_RESULT (r) = new_decl;
5850 DECL_TI_TEMPLATE (new_decl) = r;
5851 TREE_TYPE (r) = TREE_TYPE (new_decl);
5852 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
5855 SET_DECL_IMPLICIT_INSTANTIATION (r);
5856 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
5857 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
5859 /* The template parameters for this new template are all the
5860 template parameters for the old template, except the
5861 outermost level of parameters. */
5862 DECL_TEMPLATE_PARMS (r)
5863 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
5866 if (PRIMARY_TEMPLATE_P (t))
5867 DECL_PRIMARY_TEMPLATE (r) = r;
5869 /* We don't partially instantiate partial specializations. */
5870 if (TREE_CODE (decl) == TYPE_DECL)
5873 /* Record this partial instantiation. */
5874 register_specialization (r, t,
5875 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
5883 tree argvec = NULL_TREE;
5890 /* Nobody should be tsubst'ing into non-template functions. */
5891 my_friendly_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE, 0);
5893 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
5898 /* If T is not dependent, just return it. We have to
5899 increment PROCESSING_TEMPLATE_DECL because
5900 value_dependent_expression_p assumes that nothing is
5901 dependent when PROCESSING_TEMPLATE_DECL is zero. */
5902 ++processing_template_decl;
5903 dependent_p = value_dependent_expression_p (t);
5904 --processing_template_decl;
5908 /* Calculate the most general template of which R is a
5909 specialization, and the complete set of arguments used to
5911 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
5913 = tsubst_template_arg_vector (DECL_TI_ARGS
5914 (DECL_TEMPLATE_RESULT (gen_tmpl)),
5917 /* Check to see if we already have this specialization. */
5918 spec = retrieve_specialization (gen_tmpl, argvec);
5926 /* We can see more levels of arguments than parameters if
5927 there was a specialization of a member template, like
5930 template <class T> struct S { template <class U> void f(); }
5931 template <> template <class U> void S<int>::f(U);
5933 Here, we'll be substituting into the specialization,
5934 because that's where we can find the code we actually
5935 want to generate, but we'll have enough arguments for
5936 the most general template.
5938 We also deal with the peculiar case:
5940 template <class T> struct S {
5941 template <class U> friend void f();
5943 template <class U> void f() {}
5945 template void f<double>();
5947 Here, the ARGS for the instantiation of will be {int,
5948 double}. But, we only need as many ARGS as there are
5949 levels of template parameters in CODE_PATTERN. We are
5950 careful not to get fooled into reducing the ARGS in
5953 template <class T> struct S { template <class U> void f(U); }
5954 template <class T> template <> void S<T>::f(int) {}
5956 which we can spot because the pattern will be a
5957 specialization in this case. */
5958 args_depth = TMPL_ARGS_DEPTH (args);
5960 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
5961 if (args_depth > parms_depth
5962 && !DECL_TEMPLATE_SPECIALIZATION (t))
5963 args = get_innermost_template_args (args, parms_depth);
5967 /* This special case arises when we have something like this:
5969 template <class T> struct S {
5970 friend void f<int>(int, double);
5973 Here, the DECL_TI_TEMPLATE for the friend declaration
5974 will be a LOOKUP_EXPR or an IDENTIFIER_NODE. We are
5975 being called from tsubst_friend_function, and we want
5976 only to create a new decl (R) with appropriate types so
5977 that we can call determine_specialization. */
5978 gen_tmpl = NULL_TREE;
5981 if (DECL_CLASS_SCOPE_P (t))
5983 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
5987 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
5989 /*entering_scope=*/1);
5994 ctx = DECL_CONTEXT (t);
5996 type = tsubst (type, args, complain, in_decl);
5997 if (type == error_mark_node)
5998 return error_mark_node;
6000 /* We do NOT check for matching decls pushed separately at this
6001 point, as they may not represent instantiations of this
6002 template, and in any case are considered separate under the
6005 DECL_USE_TEMPLATE (r) = 0;
6006 TREE_TYPE (r) = type;
6007 /* Clear out the mangled name and RTL for the instantiation. */
6008 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6009 SET_DECL_RTL (r, NULL_RTX);
6011 DECL_CONTEXT (r) = ctx;
6013 if (member && DECL_CONV_FN_P (r))
6014 /* Type-conversion operator. Reconstruct the name, in
6015 case it's the name of one of the template's parameters. */
6016 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6018 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6020 DECL_RESULT (r) = NULL_TREE;
6022 TREE_STATIC (r) = 0;
6023 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6024 DECL_EXTERNAL (r) = 1;
6025 DECL_INTERFACE_KNOWN (r) = 0;
6026 DECL_DEFER_OUTPUT (r) = 0;
6027 TREE_CHAIN (r) = NULL_TREE;
6028 DECL_PENDING_INLINE_INFO (r) = 0;
6029 DECL_PENDING_INLINE_P (r) = 0;
6030 DECL_SAVED_TREE (r) = NULL_TREE;
6032 if (DECL_CLONED_FUNCTION (r))
6034 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6036 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6037 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6040 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6041 this in the special friend case mentioned above where
6042 GEN_TMPL is NULL. */
6045 DECL_TEMPLATE_INFO (r)
6046 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6047 SET_DECL_IMPLICIT_INSTANTIATION (r);
6048 register_specialization (r, gen_tmpl, argvec);
6050 /* We're not supposed to instantiate default arguments
6051 until they are called, for a template. But, for a
6054 template <class T> void f ()
6055 { extern void g(int i = T()); }
6057 we should do the substitution when the template is
6058 instantiated. We handle the member function case in
6059 instantiate_class_template since the default arguments
6060 might refer to other members of the class. */
6062 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6063 && !uses_template_parms (argvec))
6064 tsubst_default_arguments (r);
6067 /* Copy the list of befriending classes. */
6068 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6070 friends = &TREE_CHAIN (*friends))
6072 *friends = copy_node (*friends);
6073 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6078 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6080 maybe_retrofit_in_chrg (r);
6081 if (DECL_CONSTRUCTOR_P (r))
6082 grok_ctor_properties (ctx, r);
6083 /* If this is an instantiation of a member template, clone it.
6084 If it isn't, that'll be handled by
6085 clone_constructors_and_destructors. */
6086 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6087 clone_function_decl (r, /*update_method_vec_p=*/0);
6089 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6090 grok_op_properties (r, DECL_FRIEND_P (r));
6097 if (DECL_TEMPLATE_PARM_P (t))
6098 SET_DECL_TEMPLATE_PARM_P (r);
6100 TREE_TYPE (r) = type;
6101 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6103 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6104 DECL_INITIAL (r) = TREE_TYPE (r);
6106 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6109 DECL_CONTEXT (r) = NULL_TREE;
6111 if (!DECL_TEMPLATE_PARM_P (r))
6112 DECL_ARG_TYPE (r) = type_passed_as (type);
6114 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6115 complain, TREE_CHAIN (t));
6122 TREE_TYPE (r) = type;
6123 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6125 /* We don't have to set DECL_CONTEXT here; it is set by
6126 finish_member_declaration. */
6127 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6129 TREE_CHAIN (r) = NULL_TREE;
6130 if (VOID_TYPE_P (type))
6131 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6139 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6140 TREE_CHAIN (r) = NULL_TREE;
6145 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6146 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6148 /* If this is the canonical decl, we don't have to mess with
6149 instantiations, and often we can't (for typename, template
6150 type parms and such). Note that TYPE_NAME is not correct for
6151 the above test if we've copied the type for a typedef. */
6152 r = TYPE_NAME (type);
6160 tree argvec = NULL_TREE;
6161 tree gen_tmpl = NULL_TREE;
6163 tree tmpl = NULL_TREE;
6167 /* Assume this is a non-local variable. */
6170 if (TYPE_P (CP_DECL_CONTEXT (t)))
6171 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6173 in_decl, /*entering_scope=*/1);
6174 else if (DECL_NAMESPACE_SCOPE_P (t))
6175 ctx = DECL_CONTEXT (t);
6178 /* Subsequent calls to pushdecl will fill this in. */
6183 /* Check to see if we already have this specialization. */
6186 tmpl = DECL_TI_TEMPLATE (t);
6187 gen_tmpl = most_general_template (tmpl);
6188 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6189 spec = retrieve_specialization (gen_tmpl, argvec);
6192 spec = retrieve_local_specialization (t);
6201 if (TREE_CODE (r) == VAR_DECL)
6202 type = complete_type (type);
6203 TREE_TYPE (r) = type;
6204 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6205 DECL_CONTEXT (r) = ctx;
6206 /* Clear out the mangled name and RTL for the instantiation. */
6207 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6208 SET_DECL_RTL (r, NULL_RTX);
6210 /* Don't try to expand the initializer until someone tries to use
6211 this variable; otherwise we run into circular dependencies. */
6212 DECL_INITIAL (r) = NULL_TREE;
6213 SET_DECL_RTL (r, NULL_RTX);
6214 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6216 /* Even if the original location is out of scope, the newly
6217 substituted one is not. */
6218 if (TREE_CODE (r) == VAR_DECL)
6220 DECL_DEAD_FOR_LOCAL (r) = 0;
6221 DECL_INITIALIZED_P (r) = 0;
6226 /* A static data member declaration is always marked
6227 external when it is declared in-class, even if an
6228 initializer is present. We mimic the non-template
6230 DECL_EXTERNAL (r) = 1;
6232 register_specialization (r, gen_tmpl, argvec);
6233 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6234 SET_DECL_IMPLICIT_INSTANTIATION (r);
6237 register_local_specialization (r, t);
6239 TREE_CHAIN (r) = NULL_TREE;
6240 if (TREE_CODE (r) == VAR_DECL && VOID_TYPE_P (type))
6241 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6242 /* Compute the size, alignment, etc. of R. */
6251 /* Restore the file and line information. */
6252 input_location = saved_loc;
6257 /* Substitute into the ARG_TYPES of a function type. */
6260 tsubst_arg_types (tree arg_types,
6262 tsubst_flags_t complain,
6265 tree remaining_arg_types;
6268 if (!arg_types || arg_types == void_list_node)
6271 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6272 args, complain, in_decl);
6273 if (remaining_arg_types == error_mark_node)
6274 return error_mark_node;
6276 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6277 if (type == error_mark_node)
6278 return error_mark_node;
6279 if (VOID_TYPE_P (type))
6281 if (complain & tf_error)
6283 error ("invalid parameter type `%T'", type);
6285 cp_error_at ("in declaration `%D'", in_decl);
6287 return error_mark_node;
6290 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6291 top-level qualifiers as required. */
6292 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6294 /* Note that we do not substitute into default arguments here. The
6295 standard mandates that they be instantiated only when needed,
6296 which is done in build_over_call. */
6297 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6298 remaining_arg_types);
6302 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6303 *not* handle the exception-specification for FNTYPE, because the
6304 initial substitution of explicitly provided template parameters
6305 during argument deduction forbids substitution into the
6306 exception-specification:
6310 All references in the function type of the function template to the
6311 corresponding template parameters are replaced by the specified tem-
6312 plate argument values. If a substitution in a template parameter or
6313 in the function type of the function template results in an invalid
6314 type, type deduction fails. [Note: The equivalent substitution in
6315 exception specifications is done only when the function is instanti-
6316 ated, at which point a program is ill-formed if the substitution
6317 results in an invalid type.] */
6320 tsubst_function_type (tree t,
6322 tsubst_flags_t complain,
6329 /* The TYPE_CONTEXT is not used for function/method types. */
6330 my_friendly_assert (TYPE_CONTEXT (t) == NULL_TREE, 0);
6332 /* Substitute the return type. */
6333 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6334 if (return_type == error_mark_node)
6335 return error_mark_node;
6337 /* Substitute the argument types. */
6338 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6340 if (arg_types == error_mark_node)
6341 return error_mark_node;
6343 /* Construct a new type node and return it. */
6344 if (TREE_CODE (t) == FUNCTION_TYPE)
6345 fntype = build_function_type (return_type, arg_types);
6348 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6349 if (! IS_AGGR_TYPE (r))
6353 Type deduction may fail for any of the following
6356 -- Attempting to create "pointer to member of T" when T
6357 is not a class type. */
6358 if (complain & tf_error)
6359 error ("creating pointer to member function of non-class type `%T'",
6361 return error_mark_node;
6364 fntype = build_cplus_method_type (r, return_type, TREE_CHAIN
6367 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6368 fntype = build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6373 /* Substitute into the PARMS of a call-declarator. */
6376 tsubst_call_declarator_parms (tree parms,
6378 tsubst_flags_t complain,
6385 if (!parms || parms == void_list_node)
6388 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6389 args, complain, in_decl);
6391 /* Figure out the type of this parameter. */
6392 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6394 /* Figure out the default argument as well. Note that we use
6395 tsubst_expr since the default argument is really an expression. */
6396 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6398 /* Chain this parameter on to the front of those we have already
6399 processed. We don't use hash_tree_cons because that function
6400 doesn't check TREE_PARMLIST. */
6401 new_parms = tree_cons (defarg, type, new_parms);
6403 /* And note that these are parameters. */
6404 TREE_PARMLIST (new_parms) = 1;
6409 /* Take the tree structure T and replace template parameters used
6410 therein with the argument vector ARGS. IN_DECL is an associated
6411 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6412 Issue error and warning messages under control of COMPLAIN. Note
6413 that we must be relatively non-tolerant of extensions here, in
6414 order to preserve conformance; if we allow substitutions that
6415 should not be allowed, we may allow argument deductions that should
6416 not succeed, and therefore report ambiguous overload situations
6417 where there are none. In theory, we could allow the substitution,
6418 but indicate that it should have failed, and allow our caller to
6419 make sure that the right thing happens, but we don't try to do this
6422 This function is used for dealing with types, decls and the like;
6423 for expressions, use tsubst_expr or tsubst_copy. */
6426 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6430 if (t == NULL_TREE || t == error_mark_node
6431 || t == integer_type_node
6432 || t == void_type_node
6433 || t == char_type_node
6434 || TREE_CODE (t) == NAMESPACE_DECL)
6437 if (TREE_CODE (t) == IDENTIFIER_NODE)
6438 type = IDENTIFIER_TYPE_VALUE (t);
6440 type = TREE_TYPE (t);
6441 if (type == unknown_type_node)
6444 if (type && TREE_CODE (t) != FUNCTION_DECL
6445 && TREE_CODE (t) != TYPENAME_TYPE
6446 && TREE_CODE (t) != TEMPLATE_DECL
6447 && TREE_CODE (t) != IDENTIFIER_NODE
6448 && TREE_CODE (t) != FUNCTION_TYPE
6449 && TREE_CODE (t) != METHOD_TYPE)
6450 type = tsubst (type, args, complain, in_decl);
6451 if (type == error_mark_node)
6452 return error_mark_node;
6455 return tsubst_decl (t, args, type, complain);
6457 switch (TREE_CODE (t))
6462 return tsubst_aggr_type (t, args, complain, in_decl,
6463 /*entering_scope=*/0);
6466 case IDENTIFIER_NODE:
6478 if (t == integer_type_node)
6481 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6482 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6486 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6488 max = tsubst_expr (omax, args, complain, in_decl);
6489 if (max == error_mark_node)
6490 return error_mark_node;
6492 /* See if we can reduce this expression to something simpler. */
6493 max = maybe_fold_nontype_arg (max);
6494 if (!processing_template_decl)
6495 max = decl_constant_value (max);
6497 if (processing_template_decl
6498 /* When providing explicit arguments to a template
6499 function, but leaving some arguments for subsequent
6500 deduction, MAX may be template-dependent even if we're
6501 not PROCESSING_TEMPLATE_DECL. We still need to check for
6502 template parms, though; MAX won't be an INTEGER_CST for
6503 dynamic arrays, either. */
6504 || (TREE_CODE (max) != INTEGER_CST
6505 && uses_template_parms (max)))
6507 tree itype = make_node (INTEGER_TYPE);
6508 TYPE_MIN_VALUE (itype) = size_zero_node;
6509 TYPE_MAX_VALUE (itype) = build_min (MINUS_EXPR, sizetype, max,
6514 if (integer_zerop (omax))
6516 /* Still allow an explicit array of size zero. */
6518 pedwarn ("creating array with size zero");
6520 else if (integer_zerop (max)
6521 || (TREE_CODE (max) == INTEGER_CST
6522 && INT_CST_LT (max, integer_zero_node)))
6526 Type deduction may fail for any of the following
6529 Attempting to create an array with a size that is
6530 zero or negative. */
6531 if (complain & tf_error)
6532 error ("creating array with size zero (`%E')", max);
6534 return error_mark_node;
6537 return compute_array_index_type (NULL_TREE, max);
6540 case TEMPLATE_TYPE_PARM:
6541 case TEMPLATE_TEMPLATE_PARM:
6542 case BOUND_TEMPLATE_TEMPLATE_PARM:
6543 case TEMPLATE_PARM_INDEX:
6551 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6552 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6553 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6555 idx = TEMPLATE_TYPE_IDX (t);
6556 level = TEMPLATE_TYPE_LEVEL (t);
6560 idx = TEMPLATE_PARM_IDX (t);
6561 level = TEMPLATE_PARM_LEVEL (t);
6564 if (TREE_VEC_LENGTH (args) > 0)
6566 tree arg = NULL_TREE;
6568 levels = TMPL_ARGS_DEPTH (args);
6569 if (level <= levels)
6570 arg = TMPL_ARG (args, level, idx);
6572 if (arg == error_mark_node)
6573 return error_mark_node;
6574 else if (arg != NULL_TREE)
6576 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6578 my_friendly_assert (TYPE_P (arg), 0);
6579 return cp_build_qualified_type_real
6580 (arg, cp_type_quals (arg) | cp_type_quals (t),
6581 complain | tf_ignore_bad_quals);
6583 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6585 /* We are processing a type constructed from
6586 a template template parameter */
6587 tree argvec = tsubst (TYPE_TI_ARGS (t),
6588 args, complain, in_decl);
6589 if (argvec == error_mark_node)
6590 return error_mark_node;
6592 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6593 we are resolving nested-types in the signature of
6594 a member function templates.
6595 Otherwise ARG is a TEMPLATE_DECL and is the real
6596 template to be instantiated. */
6597 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
6598 arg = TYPE_NAME (arg);
6600 r = lookup_template_class (arg,
6603 /*entering_scope=*/0,
6605 return cp_build_qualified_type_real
6606 (r, TYPE_QUALS (t), complain);
6609 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
6617 /* This can happen during the attempted tsubst'ing in
6618 unify. This means that we don't yet have any information
6619 about the template parameter in question. */
6622 /* If we get here, we must have been looking at a parm for a
6623 more deeply nested template. Make a new version of this
6624 template parameter, but with a lower level. */
6625 switch (TREE_CODE (t))
6627 case TEMPLATE_TYPE_PARM:
6628 case TEMPLATE_TEMPLATE_PARM:
6629 case BOUND_TEMPLATE_TEMPLATE_PARM:
6630 if (cp_type_quals (t))
6632 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
6633 r = cp_build_qualified_type_real
6634 (r, cp_type_quals (t),
6635 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6636 ? tf_ignore_bad_quals : 0));
6641 TEMPLATE_TYPE_PARM_INDEX (r)
6642 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
6644 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
6645 TYPE_MAIN_VARIANT (r) = r;
6646 TYPE_POINTER_TO (r) = NULL_TREE;
6647 TYPE_REFERENCE_TO (r) = NULL_TREE;
6649 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6651 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
6653 if (argvec == error_mark_node)
6654 return error_mark_node;
6656 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
6657 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
6662 case TEMPLATE_PARM_INDEX:
6663 r = reduce_template_parm_level (t, type, levels);
6675 tree purpose, value, chain, result;
6677 if (t == void_list_node)
6680 purpose = TREE_PURPOSE (t);
6683 purpose = tsubst (purpose, args, complain, in_decl);
6684 if (purpose == error_mark_node)
6685 return error_mark_node;
6687 value = TREE_VALUE (t);
6690 value = tsubst (value, args, complain, in_decl);
6691 if (value == error_mark_node)
6692 return error_mark_node;
6694 chain = TREE_CHAIN (t);
6695 if (chain && chain != void_type_node)
6697 chain = tsubst (chain, args, complain, in_decl);
6698 if (chain == error_mark_node)
6699 return error_mark_node;
6701 if (purpose == TREE_PURPOSE (t)
6702 && value == TREE_VALUE (t)
6703 && chain == TREE_CHAIN (t))
6705 if (TREE_PARMLIST (t))
6707 result = tree_cons (purpose, value, chain);
6708 TREE_PARMLIST (result) = 1;
6711 result = hash_tree_cons (purpose, value, chain);
6715 if (type != NULL_TREE)
6717 /* A binfo node. We always need to make a copy, of the node
6718 itself and of its BINFO_BASETYPES. */
6722 /* Make sure type isn't a typedef copy. */
6723 type = BINFO_TYPE (TYPE_BINFO (type));
6725 TREE_TYPE (t) = complete_type (type);
6726 if (IS_AGGR_TYPE (type))
6728 BINFO_VTABLE (t) = TYPE_BINFO_VTABLE (type);
6729 BINFO_VIRTUALS (t) = TYPE_BINFO_VIRTUALS (type);
6730 if (TYPE_BINFO_BASETYPES (type) != NULL_TREE)
6731 BINFO_BASETYPES (t) = copy_node (TYPE_BINFO_BASETYPES (type));
6736 /* Otherwise, a vector of template arguments. */
6737 return tsubst_template_arg_vector (t, args, complain);
6740 case REFERENCE_TYPE:
6742 enum tree_code code;
6744 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
6747 code = TREE_CODE (t);
6752 Type deduction may fail for any of the following
6755 -- Attempting to create a pointer to reference type.
6756 -- Attempting to create a reference to a reference type or
6757 a reference to void. */
6758 if (TREE_CODE (type) == REFERENCE_TYPE
6759 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
6761 static location_t last_loc;
6763 /* We keep track of the last time we issued this error
6764 message to avoid spewing a ton of messages during a
6765 single bad template instantiation. */
6766 if (complain & tf_error
6767 && (last_loc.line != input_line
6768 || last_loc.file != input_filename))
6770 if (TREE_CODE (type) == VOID_TYPE)
6771 error ("forming reference to void");
6773 error ("forming %s to reference type `%T'",
6774 (code == POINTER_TYPE) ? "pointer" : "reference",
6776 last_loc = input_location;
6779 return error_mark_node;
6781 else if (code == POINTER_TYPE)
6783 r = build_pointer_type (type);
6784 if (TREE_CODE (type) == METHOD_TYPE)
6785 r = build_ptrmemfunc_type (r);
6788 r = build_reference_type (type);
6789 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6791 if (r != error_mark_node)
6792 /* Will this ever be needed for TYPE_..._TO values? */
6799 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
6800 if (r == error_mark_node || !IS_AGGR_TYPE (r))
6804 Type deduction may fail for any of the following
6807 -- Attempting to create "pointer to member of T" when T
6808 is not a class type. */
6809 if (complain & tf_error)
6810 error ("creating pointer to member of non-class type `%T'", r);
6811 return error_mark_node;
6813 if (TREE_CODE (type) == REFERENCE_TYPE)
6815 if (complain & tf_error)
6816 error ("creating pointer to member reference type `%T'", type);
6818 return error_mark_node;
6820 my_friendly_assert (TREE_CODE (type) != METHOD_TYPE, 20011231);
6821 if (TREE_CODE (type) == FUNCTION_TYPE)
6822 /* This is really a method type. The cv qualifiers of the
6823 this pointer should _not_ be determined by the cv
6824 qualifiers of the class type. They should be held
6825 somewhere in the FUNCTION_TYPE, but we don't do that at
6826 the moment. Consider
6827 typedef void (Func) () const;
6829 template <typename T1> void Foo (Func T1::*);
6832 return build_cplus_method_type (TYPE_MAIN_VARIANT (r),
6834 TYPE_ARG_TYPES (type));
6836 return build_offset_type (r, type);
6844 fntype = tsubst_function_type (t, args, complain, in_decl);
6845 if (fntype == error_mark_node)
6846 return error_mark_node;
6848 /* Substitute the exception specification. */
6849 raises = TYPE_RAISES_EXCEPTIONS (t);
6852 tree list = NULL_TREE;
6854 if (! TREE_VALUE (raises))
6857 for (; raises != NULL_TREE; raises = TREE_CHAIN (raises))
6859 tree spec = TREE_VALUE (raises);
6861 spec = tsubst (spec, args, complain, in_decl);
6862 if (spec == error_mark_node)
6864 list = add_exception_specifier (list, spec, complain);
6866 fntype = build_exception_variant (fntype, list);
6872 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
6873 if (domain == error_mark_node)
6874 return error_mark_node;
6876 /* As an optimization, we avoid regenerating the array type if
6877 it will obviously be the same as T. */
6878 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
6881 /* These checks should match the ones in grokdeclarator.
6885 The deduction may fail for any of the following reasons:
6887 -- Attempting to create an array with an element type that
6888 is void, a function type, or a reference type. */
6889 if (TREE_CODE (type) == VOID_TYPE
6890 || TREE_CODE (type) == FUNCTION_TYPE
6891 || TREE_CODE (type) == REFERENCE_TYPE)
6893 if (complain & tf_error)
6894 error ("creating array of `%T'", type);
6895 return error_mark_node;
6898 r = build_cplus_array_type (type, domain);
6905 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6906 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
6908 if (e1 == error_mark_node || e2 == error_mark_node)
6909 return error_mark_node;
6911 return fold (build (TREE_CODE (t), TREE_TYPE (t), e1, e2));
6917 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6918 if (e == error_mark_node)
6919 return error_mark_node;
6921 return fold (build (TREE_CODE (t), TREE_TYPE (t), e));
6926 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
6927 in_decl, /*entering_scope=*/1);
6928 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
6931 if (ctx == error_mark_node || f == error_mark_node)
6932 return error_mark_node;
6934 if (!IS_AGGR_TYPE (ctx))
6936 if (complain & tf_error)
6937 error ("`%T' is not a class, struct, or union type",
6939 return error_mark_node;
6941 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
6943 /* Normally, make_typename_type does not require that the CTX
6944 have complete type in order to allow things like:
6946 template <class T> struct S { typename S<T>::X Y; };
6948 But, such constructs have already been resolved by this
6949 point, so here CTX really should have complete type, unless
6950 it's a partial instantiation. */
6951 ctx = complete_type (ctx);
6952 if (!COMPLETE_TYPE_P (ctx))
6954 if (complain & tf_error)
6955 cxx_incomplete_type_error (NULL_TREE, ctx);
6956 return error_mark_node;
6960 f = make_typename_type (ctx, f,
6961 (complain & tf_error) | tf_keep_type_decl);
6962 if (f == error_mark_node)
6964 if (TREE_CODE (f) == TYPE_DECL)
6966 complain |= tf_ignore_bad_quals;
6970 return cp_build_qualified_type_real
6971 (f, cp_type_quals (f) | cp_type_quals (t), complain);
6974 case UNBOUND_CLASS_TEMPLATE:
6976 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
6977 in_decl, /*entering_scope=*/1);
6978 tree name = TYPE_IDENTIFIER (t);
6980 if (ctx == error_mark_node || name == error_mark_node)
6981 return error_mark_node;
6983 return make_unbound_class_template (ctx, name, complain);
6988 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6989 if (e == error_mark_node)
6990 return error_mark_node;
6991 return make_pointer_declarator (type, e);
6996 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6997 if (e == error_mark_node)
6998 return error_mark_node;
6999 return make_reference_declarator (type, e);
7004 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7005 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7006 if (e1 == error_mark_node || e2 == error_mark_node)
7007 return error_mark_node;
7009 return build_nt (ARRAY_REF, e1, e2, tsubst_expr);
7014 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7015 tree e2 = (tsubst_call_declarator_parms
7016 (CALL_DECLARATOR_PARMS (t), args, complain, in_decl));
7017 tree e3 = tsubst (CALL_DECLARATOR_EXCEPTION_SPEC (t), args,
7020 if (e1 == error_mark_node || e2 == error_mark_node
7021 || e3 == error_mark_node)
7022 return error_mark_node;
7024 return make_call_declarator (e1, e2, CALL_DECLARATOR_QUALS (t), e3);
7029 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7030 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7031 if (e1 == error_mark_node || e2 == error_mark_node)
7032 return error_mark_node;
7034 return build_nt (TREE_CODE (t), e1, e2);
7039 tree e1 = tsubst_expr (TYPE_FIELDS (t), args, complain, in_decl);
7040 if (e1 == error_mark_node)
7041 return error_mark_node;
7043 return cp_build_qualified_type_real (TREE_TYPE (e1),
7045 | cp_type_quals (TREE_TYPE (e1)),
7050 sorry ("use of `%s' in template",
7051 tree_code_name [(int) TREE_CODE (t)]);
7052 return error_mark_node;
7056 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7057 type of the expression on the left-hand side of the "." or "->"
7061 tsubst_baselink (tree baselink, tree object_type,
7062 tree args, tsubst_flags_t complain, tree in_decl)
7065 tree qualifying_scope;
7067 tree template_args = 0;
7068 bool template_id_p = false;
7070 /* A baselink indicates a function from a base class. The
7071 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7072 non-dependent types; otherwise, the lookup could not have
7073 succeeded. However, they may indicate bases of the template
7074 class, rather than the instantiated class.
7076 In addition, lookups that were not ambiguous before may be
7077 ambiguous now. Therefore, we perform the lookup again. */
7078 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7079 fns = BASELINK_FUNCTIONS (baselink);
7080 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7082 template_id_p = true;
7083 template_args = TREE_OPERAND (fns, 1);
7084 fns = TREE_OPERAND (fns, 0);
7085 template_args = tsubst_copy_and_build (template_args, args,
7087 /*function_p=*/false);
7089 name = DECL_NAME (get_first_fn (fns));
7090 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7091 if (BASELINK_P (baselink) && template_id_p)
7092 BASELINK_FUNCTIONS (baselink)
7093 = build_nt (TEMPLATE_ID_EXPR,
7094 BASELINK_FUNCTIONS (baselink),
7097 object_type = current_class_type;
7098 return adjust_result_of_qualified_name_lookup (baselink,
7103 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7104 true if the qualified-id will be a postfix-expression in-and-of
7105 itself; false if more of the postfix-expression follows the
7106 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7110 tsubst_qualified_id (tree qualified_id, tree args,
7111 tsubst_flags_t complain, tree in_decl,
7112 bool done, bool address_p)
7120 my_friendly_assert (TREE_CODE (qualified_id) == SCOPE_REF, 20030706);
7122 /* Figure out what name to look up. */
7123 name = TREE_OPERAND (qualified_id, 1);
7124 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7127 template_args = tsubst_copy_and_build (TREE_OPERAND (name, 1),
7128 args, complain, in_decl,
7129 /*function_p=*/false);
7130 name = TREE_OPERAND (name, 0);
7134 is_template = false;
7135 template_args = NULL_TREE;
7138 /* Substitute into the qualifying scope. When there are no ARGS, we
7139 are just trying to simplify a non-dependent expression. In that
7140 case the qualifying scope may be dependent, and, in any case,
7141 substituting will not help. */
7142 scope = TREE_OPERAND (qualified_id, 0);
7145 scope = tsubst (scope, args, complain, in_decl);
7146 expr = tsubst_copy (name, args, complain, in_decl);
7150 if (!BASELINK_P (name)
7152 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0);
7154 check_accessibility_of_qualified_id (expr,
7155 /*object_type=*/NULL_TREE,
7158 /* Remember that there was a reference to this entity. */
7162 if (!args && TREE_CODE (expr) == VAR_DECL)
7163 expr = DECL_INITIAL (expr);
7167 lookup_template_function (expr, template_args);
7171 expr = (adjust_result_of_qualified_name_lookup
7172 (expr, scope, current_class_type));
7173 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7179 /* Like tsubst, but deals with expressions. This function just replaces
7180 template parms; to finish processing the resultant expression, use
7184 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7186 enum tree_code code;
7189 if (t == NULL_TREE || t == error_mark_node)
7192 code = TREE_CODE (t);
7197 r = retrieve_local_specialization (t);
7198 my_friendly_assert (r != NULL, 20020903);
7206 if (DECL_TEMPLATE_PARM_P (t))
7207 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7208 if (!DECL_CONTEXT (t))
7209 /* This is a global enumeration constant. */
7212 /* Unfortunately, we cannot just call lookup_name here.
7215 template <int I> int f() {
7217 struct S { void g() { E e = a; } };
7220 When we instantiate f<7>::S::g(), say, lookup_name is not
7221 clever enough to find f<7>::a. */
7223 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7224 /*entering_scope=*/0);
7226 for (v = TYPE_VALUES (enum_type);
7229 if (TREE_PURPOSE (v) == DECL_NAME (t))
7230 return TREE_VALUE (v);
7232 /* We didn't find the name. That should never happen; if
7233 name-lookup found it during preliminary parsing, we
7234 should find it again here during instantiation. */
7240 if (DECL_CONTEXT (t))
7244 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7245 /*entering_scope=*/1);
7246 if (ctx != DECL_CONTEXT (t))
7247 return lookup_field (ctx, DECL_NAME (t), 0, false);
7253 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7254 || local_variable_p (t))
7255 t = tsubst (t, args, complain, in_decl);
7260 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7263 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7264 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7265 args, complain, in_decl);
7266 else if (is_member_template (t))
7267 return tsubst (t, args, complain, in_decl);
7268 else if (DECL_CLASS_SCOPE_P (t)
7269 && uses_template_parms (DECL_CONTEXT (t)))
7271 /* Template template argument like the following example need
7274 template <template <class> class TT> struct C {};
7275 template <class T> struct D {
7276 template <class U> struct E {};
7281 We are processing the template argument `E' in #1 for
7282 the template instantiation #2. Originally, `E' is a
7283 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7284 have to substitute this with one having context `D<int>'. */
7286 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7287 return lookup_field (context, DECL_NAME(t), 0, false);
7290 /* Ordinary template template argument. */
7295 /* We must tsubst into a LOOKUP_EXPR in case the names to
7296 which it refers is a conversion operator; in that case the
7297 name will change. We avoid making unnecessary copies,
7300 tree id = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7302 if (id != TREE_OPERAND (t, 0))
7304 r = build_nt (LOOKUP_EXPR, id);
7305 LOOKUP_EXPR_GLOBAL (r) = LOOKUP_EXPR_GLOBAL (t);
7313 case REINTERPRET_CAST_EXPR:
7314 case CONST_CAST_EXPR:
7315 case STATIC_CAST_EXPR:
7316 case DYNAMIC_CAST_EXPR:
7319 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7320 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7324 case TRUTH_NOT_EXPR:
7327 case CONVERT_EXPR: /* Unary + */
7336 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7337 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7344 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7345 name = TREE_OPERAND (t, 1);
7346 if (TREE_CODE (name) == BIT_NOT_EXPR)
7348 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7350 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7352 else if (TREE_CODE (name) == SCOPE_REF
7353 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7355 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7357 name = TREE_OPERAND (name, 1);
7358 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7360 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7361 name = build_nt (SCOPE_REF, base, name);
7363 else if (TREE_CODE (name) == BASELINK)
7364 name = tsubst_baselink (name,
7365 non_reference (TREE_TYPE (object)),
7369 name = tsubst_copy (name, args, complain, in_decl);
7370 return build_nt (COMPONENT_REF, object, name);
7376 case TRUNC_DIV_EXPR:
7378 case FLOOR_DIV_EXPR:
7379 case ROUND_DIV_EXPR:
7380 case EXACT_DIV_EXPR:
7382 case BIT_ANDTC_EXPR:
7385 case TRUNC_MOD_EXPR:
7386 case FLOOR_MOD_EXPR:
7387 case TRUTH_ANDIF_EXPR:
7388 case TRUTH_ORIF_EXPR:
7389 case TRUTH_AND_EXPR:
7408 case PREDECREMENT_EXPR:
7409 case PREINCREMENT_EXPR:
7410 case POSTDECREMENT_EXPR:
7411 case POSTINCREMENT_EXPR:
7413 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7414 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7417 return build_nt (code,
7418 tsubst_copy (TREE_OPERAND (t, 0), args,
7420 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7425 /* This processing should really occur in tsubst_expr. However,
7426 tsubst_expr does not recurse into expressions, since it
7427 assumes that there aren't any statements inside them. So, we
7428 need to expand the STMT_EXPR here. */
7429 if (!processing_template_decl)
7431 tree stmt_expr = begin_stmt_expr ();
7432 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
7433 return finish_stmt_expr (stmt_expr);
7440 case PSEUDO_DTOR_EXPR:
7443 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7444 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7445 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7452 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7453 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7454 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7455 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7462 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7463 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7464 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7465 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7469 case TEMPLATE_ID_EXPR:
7471 /* Substituted template arguments */
7472 tree targs = tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7475 maybe_fold_nontype_args (targs);
7476 return lookup_template_function
7477 (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl), targs);
7482 tree purpose, value, chain;
7484 if (t == void_list_node)
7487 purpose = TREE_PURPOSE (t);
7489 purpose = tsubst_copy (purpose, args, complain, in_decl);
7490 value = TREE_VALUE (t);
7492 value = tsubst_copy (value, args, complain, in_decl);
7493 chain = TREE_CHAIN (t);
7494 if (chain && chain != void_type_node)
7495 chain = tsubst_copy (chain, args, complain, in_decl);
7496 if (purpose == TREE_PURPOSE (t)
7497 && value == TREE_VALUE (t)
7498 && chain == TREE_CHAIN (t))
7500 return tree_cons (purpose, value, chain);
7507 case TEMPLATE_TYPE_PARM:
7508 case TEMPLATE_TEMPLATE_PARM:
7509 case BOUND_TEMPLATE_TEMPLATE_PARM:
7510 case TEMPLATE_PARM_INDEX:
7512 case REFERENCE_TYPE:
7518 case UNBOUND_CLASS_TEMPLATE:
7521 return tsubst (t, args, complain, in_decl);
7523 case IDENTIFIER_NODE:
7524 if (IDENTIFIER_TYPENAME_P (t))
7526 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7527 return mangle_conv_op_name_for_type (new_type);
7534 r = build_constructor
7535 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7536 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7537 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7542 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7544 tsubst (TREE_TYPE (t), args, complain, in_decl));
7551 /* Like tsubst_copy for expressions, etc. but also does semantic
7555 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7559 if (t == NULL_TREE || t == error_mark_node)
7562 if (processing_template_decl)
7563 return tsubst_copy (t, args, complain, in_decl);
7565 if (!STATEMENT_CODE_P (TREE_CODE (t)))
7566 return tsubst_copy_and_build (t, args, complain, in_decl,
7567 /*function_p=*/false);
7569 switch (TREE_CODE (t))
7571 case CTOR_INITIALIZER:
7573 finish_mem_initializers (tsubst_initializer_list
7574 (TREE_OPERAND (t, 0), args));
7579 finish_return_stmt (tsubst_expr (RETURN_STMT_EXPR (t),
7580 args, complain, in_decl));
7585 finish_expr_stmt (tsubst_expr (EXPR_STMT_EXPR (t),
7586 args, complain, in_decl));
7591 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
7592 args, complain, in_decl));
7601 decl = DECL_STMT_DECL (t);
7602 if (TREE_CODE (decl) == LABEL_DECL)
7603 finish_label_decl (DECL_NAME (decl));
7604 else if (TREE_CODE (decl) == USING_DECL)
7606 tree scope = DECL_INITIAL (decl);
7607 tree name = DECL_NAME (decl);
7609 scope = tsubst_expr (scope, args, complain, in_decl);
7610 do_local_using_decl (lookup_qualified_name (scope,
7616 init = DECL_INITIAL (decl);
7617 decl = tsubst (decl, args, complain, in_decl);
7618 if (decl != error_mark_node)
7621 DECL_INITIAL (decl) = error_mark_node;
7622 /* By marking the declaration as instantiated, we avoid
7623 trying to instantiate it. Since instantiate_decl can't
7624 handle local variables, and since we've already done
7625 all that needs to be done, that's the right thing to
7627 if (TREE_CODE (decl) == VAR_DECL)
7628 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7629 if (TREE_CODE (decl) == VAR_DECL
7630 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
7631 /* Anonymous aggregates are a special case. */
7632 finish_anon_union (decl);
7635 maybe_push_decl (decl);
7636 if (DECL_PRETTY_FUNCTION_P (decl))
7638 /* For __PRETTY_FUNCTION__ we have to adjust the
7640 const char *const name
7641 = cxx_printable_name (current_function_decl, 2);
7642 init = cp_fname_init (name);
7643 TREE_TYPE (decl) = TREE_TYPE (init);
7646 init = tsubst_expr (init, args, complain, in_decl);
7647 cp_finish_decl (decl, init, NULL_TREE, 0);
7652 /* A DECL_STMT can also be used as an expression, in the condition
7653 clause of an if/for/while construct. If we aren't followed by
7654 another statement, return our decl. */
7655 if (TREE_CHAIN (t) == NULL_TREE)
7664 stmt = begin_for_stmt ();
7665 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
7666 finish_for_init_stmt (stmt);
7667 finish_for_cond (tsubst_expr (FOR_COND (t),
7668 args, complain, in_decl),
7670 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
7671 finish_for_expr (tmp, stmt);
7672 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
7673 finish_for_stmt (stmt);
7680 stmt = begin_while_stmt ();
7681 finish_while_stmt_cond (tsubst_expr (WHILE_COND (t),
7682 args, complain, in_decl),
7684 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
7685 finish_while_stmt (stmt);
7692 stmt = begin_do_stmt ();
7693 tsubst_expr (DO_BODY (t), args, complain, in_decl);
7694 finish_do_body (stmt);
7695 finish_do_stmt (tsubst_expr (DO_COND (t),
7696 args, complain, in_decl),
7704 stmt = begin_if_stmt ();
7705 finish_if_stmt_cond (tsubst_expr (IF_COND (t),
7706 args, complain, in_decl),
7709 if (tmp = THEN_CLAUSE (t), tmp)
7711 tsubst_expr (tmp, args, complain, in_decl);
7712 finish_then_clause (stmt);
7715 if (tmp = ELSE_CLAUSE (t), tmp)
7717 begin_else_clause ();
7718 tsubst_expr (tmp, args, complain, in_decl);
7719 finish_else_clause (stmt);
7729 if (COMPOUND_STMT_BODY_BLOCK (t))
7730 stmt = begin_function_body ();
7732 stmt = begin_compound_stmt (COMPOUND_STMT_NO_SCOPE (t));
7734 tsubst_expr (COMPOUND_BODY (t), args, complain, in_decl);
7736 if (COMPOUND_STMT_BODY_BLOCK (t))
7737 finish_function_body (stmt);
7739 finish_compound_stmt (COMPOUND_STMT_NO_SCOPE (t), stmt);
7745 finish_break_stmt ();
7750 finish_continue_stmt ();
7758 stmt = begin_switch_stmt ();
7759 val = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
7760 finish_switch_cond (val, stmt);
7761 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
7762 finish_switch_stmt (stmt);
7768 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
7769 tsubst_expr (CASE_HIGH (t), args, complain,
7774 input_line = STMT_LINENO (t);
7775 finish_label_stmt (DECL_NAME (LABEL_STMT_LABEL (t)));
7779 input_filename = FILE_STMT_FILENAME (t);
7780 add_stmt (build_nt (FILE_STMT, FILE_STMT_FILENAME_NODE (t)));
7785 tmp = GOTO_DESTINATION (t);
7786 if (TREE_CODE (tmp) != LABEL_DECL)
7787 /* Computed goto's must be tsubst'd into. On the other hand,
7788 non-computed gotos must not be; the identifier in question
7789 will have no binding. */
7790 tmp = tsubst_expr (tmp, args, complain, in_decl);
7792 tmp = DECL_NAME (tmp);
7793 finish_goto_stmt (tmp);
7798 tmp = finish_asm_stmt
7800 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
7801 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
7802 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
7803 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
7804 ASM_INPUT_P (tmp) = ASM_INPUT_P (t);
7811 stmt = begin_try_block ();
7812 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7813 finish_cleanup_try_block (stmt);
7814 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
7820 if (FN_TRY_BLOCK_P (t))
7821 stmt = begin_function_try_block ();
7823 stmt = begin_try_block ();
7825 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7827 if (FN_TRY_BLOCK_P (t))
7828 finish_function_try_block (stmt);
7830 finish_try_block (stmt);
7832 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
7833 if (FN_TRY_BLOCK_P (t))
7834 finish_function_handler_sequence (stmt);
7836 finish_handler_sequence (stmt);
7845 stmt = begin_handler ();
7846 if (HANDLER_PARMS (t))
7848 decl = DECL_STMT_DECL (HANDLER_PARMS (t));
7849 decl = tsubst (decl, args, complain, in_decl);
7850 /* Prevent instantiate_decl from trying to instantiate
7851 this variable. We've already done all that needs to be
7853 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7857 finish_handler_parms (decl, stmt);
7858 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
7859 finish_handler (stmt);
7865 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
7872 return tsubst_expr (TREE_CHAIN (t), args, complain, in_decl);
7875 /* T is a postfix-expression that is not being used in a function
7876 call. Return the substituted version of T. */
7879 tsubst_non_call_postfix_expression (tree t, tree args,
7880 tsubst_flags_t complain,
7883 if (TREE_CODE (t) == SCOPE_REF)
7884 t = tsubst_qualified_id (t, args, complain, in_decl,
7885 /*done=*/false, /*address_p=*/false);
7887 t = tsubst_copy_and_build (t, args, complain, in_decl,
7888 /*function_p=*/false);
7893 /* Like tsubst but deals with expressions and performs semantic
7894 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
7897 tsubst_copy_and_build (tree t,
7899 tsubst_flags_t complain,
7903 #define RECUR(NODE) \
7904 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
7908 if (t == NULL_TREE || t == error_mark_node)
7911 switch (TREE_CODE (t))
7914 case IDENTIFIER_NODE:
7919 tree qualifying_class;
7920 bool non_constant_expression_p;
7921 const char *error_msg;
7923 /* Remember whether this identifier was explicitly qualified
7925 if (TREE_CODE (t) == LOOKUP_EXPR && LOOKUP_EXPR_GLOBAL (t))
7926 scope = global_namespace;
7929 /* Get at the underlying identifier. */
7930 if (TREE_CODE (t) == LOOKUP_EXPR)
7931 t = TREE_OPERAND (t, 0);
7933 if (IDENTIFIER_TYPENAME_P (t))
7935 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7936 t = mangle_conv_op_name_for_type (new_type);
7939 /* Look up the name. */
7940 if (scope == global_namespace)
7941 decl = IDENTIFIER_GLOBAL_VALUE (t);
7943 decl = lookup_name (t, 0);
7945 /* By convention, expressions use ERROR_MARK_NODE to indicate
7946 failure, not NULL_TREE. */
7947 if (decl == NULL_TREE)
7948 decl = error_mark_node;
7950 decl = finish_id_expression (t, decl, scope,
7953 /*constant_expression_p=*/false,
7954 /*allow_non_constant_expression_p=*/false,
7955 &non_constant_expression_p,
7959 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
7960 decl = unqualified_name_lookup_error (decl);
7964 case TEMPLATE_ID_EXPR:
7967 tree template = RECUR (TREE_OPERAND (t, 0));
7968 tree targs = RECUR (TREE_OPERAND (t, 1));
7970 if (TREE_CODE (template) == COMPONENT_REF)
7972 object = TREE_OPERAND (template, 0);
7973 template = TREE_OPERAND (template, 1);
7977 template = lookup_template_function (template, targs);
7980 return build (COMPONENT_REF, TREE_TYPE (template),
7987 return build_x_indirect_ref (RECUR (TREE_OPERAND (t, 0)), "unary *");
7990 return build_functional_cast
7991 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7992 RECUR (TREE_OPERAND (t, 0)));
7994 case REINTERPRET_CAST_EXPR:
7995 return build_reinterpret_cast
7996 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7997 RECUR (TREE_OPERAND (t, 0)));
7999 case CONST_CAST_EXPR:
8000 return build_const_cast
8001 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8002 RECUR (TREE_OPERAND (t, 0)));
8004 case DYNAMIC_CAST_EXPR:
8005 return build_dynamic_cast
8006 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8007 RECUR (TREE_OPERAND (t, 0)));
8009 case STATIC_CAST_EXPR:
8010 return build_static_cast
8011 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8012 RECUR (TREE_OPERAND (t, 0)));
8014 case POSTDECREMENT_EXPR:
8015 case POSTINCREMENT_EXPR:
8016 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8017 args, complain, in_decl);
8018 return build_x_unary_op (TREE_CODE (t), op1);
8020 case PREDECREMENT_EXPR:
8021 case PREINCREMENT_EXPR:
8025 case TRUTH_NOT_EXPR:
8026 case CONVERT_EXPR: /* Unary + */
8029 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8032 op1 = TREE_OPERAND (t, 0);
8033 if (TREE_CODE (op1) == SCOPE_REF)
8034 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8035 /*done=*/true, /*address_p=*/true);
8037 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8039 return build_x_unary_op (ADDR_EXPR, op1);
8044 case TRUNC_DIV_EXPR:
8046 case FLOOR_DIV_EXPR:
8047 case ROUND_DIV_EXPR:
8048 case EXACT_DIV_EXPR:
8050 case BIT_ANDTC_EXPR:
8053 case TRUNC_MOD_EXPR:
8054 case FLOOR_MOD_EXPR:
8055 case TRUTH_ANDIF_EXPR:
8056 case TRUTH_ORIF_EXPR:
8057 case TRUTH_AND_EXPR:
8073 return build_x_binary_op
8075 RECUR (TREE_OPERAND (t, 0)),
8076 RECUR (TREE_OPERAND (t, 1)));
8079 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8080 /*address_p=*/false);
8083 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8086 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)));
8088 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8089 args, complain, in_decl);
8090 /* Remember that there was a reference to this entity. */
8093 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8097 op1 = TREE_OPERAND (t, 0);
8100 /* When there are no ARGS, we are trying to evaluate a
8101 non-dependent expression from the parser. Trying to do
8102 the substitutions may not work. */
8104 op1 = TREE_TYPE (op1);
8112 if (TREE_CODE (t) == SIZEOF_EXPR)
8113 return finish_sizeof (op1);
8115 return finish_alignof (op1);
8118 return build_x_modify_expr
8119 (RECUR (TREE_OPERAND (t, 0)),
8120 TREE_CODE (TREE_OPERAND (t, 1)),
8121 RECUR (TREE_OPERAND (t, 2)));
8124 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8125 args, complain, in_decl);
8126 /* Remember that there was a reference to this entity. */
8129 return build_x_arrow (op1);
8133 (RECUR (TREE_OPERAND (t, 0)),
8134 RECUR (TREE_OPERAND (t, 1)),
8135 RECUR (TREE_OPERAND (t, 2)),
8136 NEW_EXPR_USE_GLOBAL (t));
8139 return delete_sanity
8140 (RECUR (TREE_OPERAND (t, 0)),
8141 RECUR (TREE_OPERAND (t, 1)),
8142 DELETE_EXPR_USE_VEC (t),
8143 DELETE_EXPR_USE_GLOBAL (t));
8146 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8147 RECUR (TREE_OPERAND (t, 1)));
8155 function = TREE_OPERAND (t, 0);
8156 if (TREE_CODE (function) == SCOPE_REF)
8159 function = tsubst_qualified_id (function, args, complain, in_decl,
8161 /*address_p=*/false);
8165 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8166 && (TREE_CODE (TREE_OPERAND (function, 1))
8168 function = tsubst_copy_and_build (function, args, complain,
8173 call_args = RECUR (TREE_OPERAND (t, 1));
8175 if (BASELINK_P (function))
8179 && TREE_CODE (function) != TEMPLATE_ID_EXPR
8180 && (is_overloaded_fn (function)
8181 || DECL_P (function)
8182 || TREE_CODE (function) == IDENTIFIER_NODE))
8185 function = perform_koenig_lookup (function, call_args);
8186 else if (TREE_CODE (function) == IDENTIFIER_NODE)
8187 function = unqualified_name_lookup_error (function);
8190 /* Remember that there was a reference to this entity. */
8191 if (DECL_P (function))
8192 mark_used (function);
8194 function = convert_from_reference (function);
8196 if (TREE_CODE (function) == OFFSET_REF)
8197 return build_offset_ref_call_from_tree (function, call_args);
8198 if (TREE_CODE (function) == COMPONENT_REF)
8199 return (build_new_method_call
8200 (TREE_OPERAND (function, 0),
8201 TREE_OPERAND (function, 1),
8202 call_args, NULL_TREE,
8203 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8204 return finish_call_expr (function, call_args,
8205 /*disallow_virtual=*/qualified_p);
8209 return build_x_conditional_expr
8210 (RECUR (TREE_OPERAND (t, 0)),
8211 RECUR (TREE_OPERAND (t, 1)),
8212 RECUR (TREE_OPERAND (t, 2)));
8214 case PSEUDO_DTOR_EXPR:
8215 return finish_pseudo_destructor_expr
8216 (RECUR (TREE_OPERAND (t, 0)),
8217 RECUR (TREE_OPERAND (t, 1)),
8218 RECUR (TREE_OPERAND (t, 2)));
8222 tree purpose, value, chain;
8224 if (t == void_list_node)
8227 purpose = TREE_PURPOSE (t);
8229 purpose = RECUR (purpose);
8230 value = TREE_VALUE (t);
8232 value = RECUR (value);
8233 chain = TREE_CHAIN (t);
8234 if (chain && chain != void_type_node)
8235 chain = RECUR (chain);
8236 if (purpose == TREE_PURPOSE (t)
8237 && value == TREE_VALUE (t)
8238 && chain == TREE_CHAIN (t))
8240 return tree_cons (purpose, value, chain);
8248 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8249 args, complain, in_decl);
8250 /* Remember that there was a reference to this entity. */
8251 if (DECL_P (object))
8254 member = TREE_OPERAND (t, 1);
8255 if (BASELINK_P (member))
8256 member = tsubst_baselink (member,
8257 non_reference (TREE_TYPE (object)),
8258 args, complain, in_decl);
8260 member = tsubst_copy (member, args, complain, in_decl);
8262 if (!CLASS_TYPE_P (TREE_TYPE (object)))
8264 if (TREE_CODE (member) == BIT_NOT_EXPR)
8265 return finish_pseudo_destructor_expr (object,
8267 TREE_TYPE (object));
8268 else if (TREE_CODE (member) == SCOPE_REF
8269 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8270 return finish_pseudo_destructor_expr (object,
8272 TREE_TYPE (object));
8274 else if (TREE_CODE (member) == SCOPE_REF
8275 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8280 /* Lookup the template functions now that we know what the
8282 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8283 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8284 member = lookup_qualified_name (TREE_OPERAND (member, 0),
8287 if (BASELINK_P (member))
8288 BASELINK_FUNCTIONS (member)
8289 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8293 error ("`%D' is not a member of `%T'",
8294 tmpl, TREE_TYPE (object));
8295 return error_mark_node;
8299 return finish_class_member_access_expr (object, member);
8304 (RECUR (TREE_OPERAND (t, 0)));
8310 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8313 /* digest_init will do the wrong thing if we let it. */
8314 if (type && TYPE_PTRMEMFUNC_P (type))
8318 /* We do not want to process the purpose of aggregate
8319 initializers as they are identifier nodes which will be
8320 looked up by digest_init. */
8321 purpose_p = !(type && IS_AGGR_TYPE (type));
8322 for (elts = CONSTRUCTOR_ELTS (t);
8324 elts = TREE_CHAIN (elts))
8326 tree purpose = TREE_PURPOSE (elts);
8327 tree value = TREE_VALUE (elts);
8329 if (purpose && purpose_p)
8330 purpose = RECUR (purpose);
8331 value = RECUR (value);
8332 r = tree_cons (purpose, value, r);
8335 r = build_constructor (NULL_TREE, nreverse (r));
8336 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8339 return digest_init (type, r, 0);
8345 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8346 if (TYPE_P (operand_0))
8347 return get_typeid (operand_0);
8348 return build_typeid (operand_0);
8352 return convert_from_reference (tsubst_copy (t, args, complain, in_decl));
8356 t = tsubst_copy (t, args, complain, in_decl);
8358 /* If there are no ARGS, then we are evaluating a
8359 non-dependent expression. If the expression is
8360 non-dependent, the variable must be a constant. */
8361 t = DECL_INITIAL (t);
8362 return convert_from_reference (t);
8365 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8366 tsubst_copy (TREE_TYPE (t), args, complain,
8370 return tsubst_copy (t, args, complain, in_decl);
8376 /* Verify that the instantiated ARGS are valid. For type arguments,
8377 make sure that the type's linkage is ok. For non-type arguments,
8378 make sure they are constants if they are integral or enumerations.
8379 Emit an error under control of COMPLAIN, and return TRUE on error. */
8382 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8384 int ix, len = DECL_NTPARMS (tmpl);
8385 bool result = false;
8387 for (ix = 0; ix != len; ix++)
8389 tree t = TREE_VEC_ELT (args, ix);
8393 /* [basic.link]: A name with no linkage (notably, the name
8394 of a class or enumeration declared in a local scope)
8395 shall not be used to declare an entity with linkage.
8396 This implies that names with no linkage cannot be used as
8397 template arguments. */
8398 tree nt = no_linkage_check (t);
8402 if (!(complain & tf_error))
8404 else if (TYPE_ANONYMOUS_P (nt))
8405 error ("`%T' uses anonymous type", t);
8407 error ("`%T' uses local type `%T'", t, nt);
8410 /* In order to avoid all sorts of complications, we do not
8411 allow variably-modified types as template arguments. */
8412 else if (variably_modified_type_p (t))
8414 if (complain & tf_error)
8415 error ("`%T' is a variably modified type", t);
8419 /* A non-type argument of integral or enumerated type must be a
8421 else if (TREE_TYPE (t)
8422 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8423 && !TREE_CONSTANT (t))
8425 if (complain & tf_error)
8426 error ("integral expression `%E' is not constant", t);
8430 if (result && complain & tf_error)
8431 error (" trying to instantiate `%D'", tmpl);
8435 /* Instantiate the indicated variable or function template TMPL with
8436 the template arguments in TARG_PTR. */
8439 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8445 if (tmpl == error_mark_node)
8446 return error_mark_node;
8448 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 283);
8450 /* If this function is a clone, handle it specially. */
8451 if (DECL_CLONED_FUNCTION_P (tmpl))
8453 tree spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8457 /* Look for the clone. */
8458 for (clone = TREE_CHAIN (spec);
8459 clone && DECL_CLONED_FUNCTION_P (clone);
8460 clone = TREE_CHAIN (clone))
8461 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8463 /* We should always have found the clone by now. */
8468 /* Check to see if we already have this specialization. */
8469 spec = retrieve_specialization (tmpl, targ_ptr);
8470 if (spec != NULL_TREE)
8473 gen_tmpl = most_general_template (tmpl);
8474 if (tmpl != gen_tmpl)
8476 /* The TMPL is a partial instantiation. To get a full set of
8477 arguments we must add the arguments used to perform the
8478 partial instantiation. */
8479 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
8482 /* Check to see if we already have this specialization. */
8483 spec = retrieve_specialization (gen_tmpl, targ_ptr);
8484 if (spec != NULL_TREE)
8488 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
8490 return error_mark_node;
8492 /* We are building a FUNCTION_DECL, during which the access of its
8493 parameters and return types have to be checked. However this
8494 FUNCTION_DECL which is the desired context for access checking
8495 is not built yet. We solve this chicken-and-egg problem by
8496 deferring all checks until we have the FUNCTION_DECL. */
8497 push_deferring_access_checks (dk_deferred);
8499 /* substitute template parameters */
8500 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
8501 targ_ptr, complain, gen_tmpl);
8503 /* Now we know the specialization, compute access previously
8505 push_access_scope (fndecl);
8506 perform_deferred_access_checks ();
8507 pop_access_scope (fndecl);
8508 pop_deferring_access_checks ();
8510 /* The DECL_TI_TEMPLATE should always be the immediate parent
8511 template, not the most general template. */
8512 DECL_TI_TEMPLATE (fndecl) = tmpl;
8514 if (flag_external_templates)
8515 add_pending_template (fndecl);
8517 /* If we've just instantiated the main entry point for a function,
8518 instantiate all the alternate entry points as well. We do this
8519 by cloning the instantiation of the main entry point, not by
8520 instantiating the template clones. */
8521 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
8522 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
8527 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8528 arguments that are being used when calling it. TARGS is a vector
8529 into which the deduced template arguments are placed.
8531 Return zero for success, 2 for an incomplete match that doesn't resolve
8532 all the types, and 1 for complete failure. An error message will be
8533 printed only for an incomplete match.
8535 If FN is a conversion operator, or we are trying to produce a specific
8536 specialization, RETURN_TYPE is the return type desired.
8538 The EXPLICIT_TARGS are explicit template arguments provided via a
8541 The parameter STRICT is one of:
8544 We are deducing arguments for a function call, as in
8548 We are deducing arguments for a conversion function, as in
8552 We are deducing arguments when doing an explicit instantiation
8553 as in [temp.explicit], when determining an explicit specialization
8554 as in [temp.expl.spec], or when taking the address of a function
8555 template, as in [temp.deduct.funcaddr].
8558 We are deducing arguments when calculating the partial
8559 ordering between specializations of function or class
8560 templates, as in [temp.func.order] and [temp.class.order].
8562 LEN is the number of parms to consider before returning success, or -1
8563 for all. This is used in partial ordering to avoid comparing parms for
8564 which no actual argument was passed, since they are not considered in
8565 overload resolution (and are explicitly excluded from consideration in
8566 partial ordering in [temp.func.order]/6). */
8569 fn_type_unification (tree fn,
8570 tree explicit_targs,
8574 unification_kind_t strict,
8581 my_friendly_assert (TREE_CODE (fn) == TEMPLATE_DECL, 0);
8583 fntype = TREE_TYPE (fn);
8588 The specified template arguments must match the template
8589 parameters in kind (i.e., type, nontype, template), and there
8590 must not be more arguments than there are parameters;
8591 otherwise type deduction fails.
8593 Nontype arguments must match the types of the corresponding
8594 nontype template parameters, or must be convertible to the
8595 types of the corresponding nontype parameters as specified in
8596 _temp.arg.nontype_, otherwise type deduction fails.
8598 All references in the function type of the function template
8599 to the corresponding template parameters are replaced by the
8600 specified template argument values. If a substitution in a
8601 template parameter or in the function type of the function
8602 template results in an invalid type, type deduction fails. */
8604 tree converted_args;
8607 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8608 explicit_targs, NULL_TREE, tf_none,
8609 /*require_all_arguments=*/0));
8610 if (converted_args == error_mark_node)
8613 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
8614 if (fntype == error_mark_node)
8617 /* Place the explicitly specified arguments in TARGS. */
8618 for (i = 0; i < TREE_VEC_LENGTH (targs); i++)
8619 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
8622 parms = TYPE_ARG_TYPES (fntype);
8623 /* Never do unification on the 'this' parameter. */
8624 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
8625 parms = TREE_CHAIN (parms);
8629 /* We've been given a return type to match, prepend it. */
8630 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
8631 args = tree_cons (NULL_TREE, return_type, args);
8636 /* We allow incomplete unification without an error message here
8637 because the standard doesn't seem to explicitly prohibit it. Our
8638 callers must be ready to deal with unification failures in any
8640 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8641 targs, parms, args, /*subr=*/0,
8642 strict, /*allow_incomplete*/1, len);
8645 /* All is well so far. Now, check:
8649 When all template arguments have been deduced, all uses of
8650 template parameters in nondeduced contexts are replaced with
8651 the corresponding deduced argument values. If the
8652 substitution results in an invalid type, as described above,
8653 type deduction fails. */
8654 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
8661 /* Adjust types before performing type deduction, as described in
8662 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
8663 sections are symmetric. PARM is the type of a function parameter
8664 or the return type of the conversion function. ARG is the type of
8665 the argument passed to the call, or the type of the value
8666 initialized with the result of the conversion function. */
8669 maybe_adjust_types_for_deduction (unification_kind_t strict,
8682 /* Swap PARM and ARG throughout the remainder of this
8683 function; the handling is precisely symmetric since PARM
8684 will initialize ARG rather than vice versa. */
8692 /* There is nothing to do in this case. */
8696 /* DR 214. [temp.func.order] is underspecified, and leads to no
8697 ordering between things like `T *' and `T const &' for `U *'.
8698 The former has T=U and the latter T=U*. The former looks more
8699 specialized and John Spicer considers it well-formed (the EDG
8700 compiler accepts it).
8702 John also confirms that deduction should proceed as in a function
8703 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
8704 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
8705 to an actual call can have such a type.
8707 If both ARG and PARM are REFERENCE_TYPE, we change neither.
8708 If only ARG is a REFERENCE_TYPE, we look through that and then
8709 proceed as with DEDUCE_CALL (which could further convert it). */
8710 if (TREE_CODE (*arg) == REFERENCE_TYPE)
8712 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8714 *arg = TREE_TYPE (*arg);
8721 if (TREE_CODE (*parm) != REFERENCE_TYPE)
8723 /* [temp.deduct.call]
8725 If P is not a reference type:
8727 --If A is an array type, the pointer type produced by the
8728 array-to-pointer standard conversion (_conv.array_) is
8729 used in place of A for type deduction; otherwise,
8731 --If A is a function type, the pointer type produced by
8732 the function-to-pointer standard conversion
8733 (_conv.func_) is used in place of A for type deduction;
8736 --If A is a cv-qualified type, the top level
8737 cv-qualifiers of A's type are ignored for type
8739 if (TREE_CODE (*arg) == ARRAY_TYPE)
8740 *arg = build_pointer_type (TREE_TYPE (*arg));
8741 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
8742 *arg = build_pointer_type (*arg);
8744 *arg = TYPE_MAIN_VARIANT (*arg);
8747 /* [temp.deduct.call]
8749 If P is a cv-qualified type, the top level cv-qualifiers
8750 of P's type are ignored for type deduction. If P is a
8751 reference type, the type referred to by P is used for
8753 *parm = TYPE_MAIN_VARIANT (*parm);
8754 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8756 *parm = TREE_TYPE (*parm);
8757 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
8760 /* DR 322. For conversion deduction, remove a reference type on parm
8761 too (which has been swapped into ARG). */
8762 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
8763 *arg = TREE_TYPE (*arg);
8768 /* Most parms like fn_type_unification.
8770 If SUBR is 1, we're being called recursively (to unify the
8771 arguments of a function or method parameter of a function
8775 type_unification_real (tree tparms,
8780 unification_kind_t strict,
8781 int allow_incomplete,
8786 int ntparms = TREE_VEC_LENGTH (tparms);
8788 int saw_undeduced = 0;
8792 my_friendly_assert (TREE_CODE (tparms) == TREE_VEC, 289);
8793 my_friendly_assert (xparms == NULL_TREE
8794 || TREE_CODE (xparms) == TREE_LIST, 290);
8795 /* ARGS could be NULL. */
8797 my_friendly_assert (TREE_CODE (xargs) == TREE_LIST, 291);
8798 my_friendly_assert (ntparms > 0, 292);
8803 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
8804 | UNIFY_ALLOW_DERIVED);
8808 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
8812 sub_strict = UNIFY_ALLOW_NONE;
8816 sub_strict = UNIFY_ALLOW_NONE;
8832 && parms != void_list_node
8834 && args != void_list_node)
8836 parm = TREE_VALUE (parms);
8837 parms = TREE_CHAIN (parms);
8838 arg = TREE_VALUE (args);
8839 args = TREE_CHAIN (args);
8841 if (arg == error_mark_node)
8843 if (arg == unknown_type_node)
8844 /* We can't deduce anything from this, but we might get all the
8845 template args from other function args. */
8848 /* Conversions will be performed on a function argument that
8849 corresponds with a function parameter that contains only
8850 non-deducible template parameters and explicitly specified
8851 template parameters. */
8852 if (! uses_template_parms (parm))
8857 type = TREE_TYPE (arg);
8864 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
8866 if (same_type_p (parm, type))
8870 /* It might work; we shouldn't check now, because we might
8871 get into infinite recursion. Overload resolution will
8880 my_friendly_assert (TREE_TYPE (arg) != NULL_TREE, 293);
8881 if (type_unknown_p (arg))
8883 /* [temp.deduct.type] A template-argument can be deduced from
8884 a pointer to function or pointer to member function
8885 argument if the set of overloaded functions does not
8886 contain function templates and at most one of a set of
8887 overloaded functions provides a unique match. */
8889 if (resolve_overloaded_unification
8890 (tparms, targs, parm, arg, strict, sub_strict)
8895 arg = TREE_TYPE (arg);
8896 if (arg == error_mark_node)
8901 int arg_strict = sub_strict;
8904 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
8906 if (unify (tparms, targs, parm, arg, arg_strict))
8910 /* Are we done with the interesting parms? */
8914 /* Fail if we've reached the end of the parm list, and more args
8915 are present, and the parm list isn't variadic. */
8916 if (args && args != void_list_node && parms == void_list_node)
8918 /* Fail if parms are left and they don't have default values. */
8920 && parms != void_list_node
8921 && TREE_PURPOSE (parms) == NULL_TREE)
8926 for (i = 0; i < ntparms; i++)
8927 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
8929 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
8931 /* If this is an undeduced nontype parameter that depends on
8932 a type parameter, try another pass; its type may have been
8933 deduced from a later argument than the one from which
8934 this parameter can be deduced. */
8935 if (TREE_CODE (tparm) == PARM_DECL
8936 && uses_template_parms (TREE_TYPE (tparm))
8937 && !saw_undeduced++)
8940 if (!allow_incomplete)
8941 error ("incomplete type unification");
8947 /* Subroutine of type_unification_real. Args are like the variables at the
8948 call site. ARG is an overloaded function (or template-id); we try
8949 deducing template args from each of the overloads, and if only one
8950 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
8953 resolve_overloaded_unification (tree tparms,
8957 unification_kind_t strict,
8960 tree tempargs = copy_node (targs);
8963 if (TREE_CODE (arg) == ADDR_EXPR)
8964 arg = TREE_OPERAND (arg, 0);
8966 if (TREE_CODE (arg) == COMPONENT_REF)
8967 /* Handle `&x' where `x' is some static or non-static member
8969 arg = TREE_OPERAND (arg, 1);
8971 if (TREE_CODE (arg) == OFFSET_REF)
8972 arg = TREE_OPERAND (arg, 1);
8974 /* Strip baselink information. */
8975 if (BASELINK_P (arg))
8976 arg = BASELINK_FUNCTIONS (arg);
8978 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
8980 /* If we got some explicit template args, we need to plug them into
8981 the affected templates before we try to unify, in case the
8982 explicit args will completely resolve the templates in question. */
8984 tree expl_subargs = TREE_OPERAND (arg, 1);
8985 arg = TREE_OPERAND (arg, 0);
8987 for (; arg; arg = OVL_NEXT (arg))
8989 tree fn = OVL_CURRENT (arg);
8992 if (TREE_CODE (fn) != TEMPLATE_DECL)
8995 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
8999 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9000 if (TREE_CODE (elem) == METHOD_TYPE)
9001 elem = build_ptrmemfunc_type (build_pointer_type (elem));
9002 good += try_one_overload (tparms, targs, tempargs, parm, elem,
9003 strict, sub_strict);
9007 else if (TREE_CODE (arg) == OVERLOAD
9008 || TREE_CODE (arg) == FUNCTION_DECL)
9010 for (; arg; arg = OVL_NEXT (arg))
9012 tree type = TREE_TYPE (OVL_CURRENT (arg));
9013 if (TREE_CODE (type) == METHOD_TYPE)
9014 type = build_ptrmemfunc_type (build_pointer_type (type));
9015 good += try_one_overload (tparms, targs, tempargs, parm,
9017 strict, sub_strict);
9023 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9024 to function or pointer to member function argument if the set of
9025 overloaded functions does not contain function templates and at most
9026 one of a set of overloaded functions provides a unique match.
9028 So if we found multiple possibilities, we return success but don't
9033 int i = TREE_VEC_LENGTH (targs);
9035 if (TREE_VEC_ELT (tempargs, i))
9036 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9044 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9045 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9046 different overloads deduce different arguments for a given parm.
9047 Returns 1 on success. */
9050 try_one_overload (tree tparms,
9055 unification_kind_t strict,
9062 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9063 to function or pointer to member function argument if the set of
9064 overloaded functions does not contain function templates and at most
9065 one of a set of overloaded functions provides a unique match.
9067 So if this is a template, just return success. */
9069 if (uses_template_parms (arg))
9072 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9074 /* We don't copy orig_targs for this because if we have already deduced
9075 some template args from previous args, unify would complain when we
9076 try to deduce a template parameter for the same argument, even though
9077 there isn't really a conflict. */
9078 nargs = TREE_VEC_LENGTH (targs);
9079 tempargs = make_tree_vec (nargs);
9081 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9084 /* First make sure we didn't deduce anything that conflicts with
9085 explicitly specified args. */
9086 for (i = nargs; i--; )
9088 tree elt = TREE_VEC_ELT (tempargs, i);
9089 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9091 if (elt == NULL_TREE)
9093 else if (uses_template_parms (elt))
9095 /* Since we're unifying against ourselves, we will fill in template
9096 args used in the function parm list with our own template parms.
9098 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9101 else if (oldelt && ! template_args_equal (oldelt, elt))
9105 for (i = nargs; i--; )
9107 tree elt = TREE_VEC_ELT (tempargs, i);
9110 TREE_VEC_ELT (targs, i) = elt;
9116 /* Verify that nondeduce template argument agrees with the type
9117 obtained from argument deduction. Return nonzero if the
9122 struct A { typedef int X; };
9123 template <class T, class U> struct C {};
9124 template <class T> struct C<T, typename T::X> {};
9126 Then with the instantiation `C<A, int>', we can deduce that
9127 `T' is `A' but unify () does not check whether `typename T::X'
9128 is `int'. This function ensure that they agree.
9130 TARGS, PARMS are the same as the arguments of unify.
9131 ARGS contains template arguments from all levels. */
9134 verify_class_unification (tree targs, tree parms, tree args)
9136 parms = tsubst (parms, add_outermost_template_args (args, targs),
9137 tf_none, NULL_TREE);
9138 if (parms == error_mark_node)
9141 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9144 /* PARM is a template class (perhaps with unbound template
9145 parameters). ARG is a fully instantiated type. If ARG can be
9146 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9147 TARGS are as for unify. */
9150 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9154 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9155 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9156 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9159 /* We need to make a new template argument vector for the call to
9160 unify. If we used TARGS, we'd clutter it up with the result of
9161 the attempted unification, even if this class didn't work out.
9162 We also don't want to commit ourselves to all the unifications
9163 we've already done, since unification is supposed to be done on
9164 an argument-by-argument basis. In other words, consider the
9165 following pathological case:
9167 template <int I, int J, int K>
9170 template <int I, int J>
9171 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9173 template <int I, int J, int K>
9174 void f(S<I, J, K>, S<I, I, I>);
9183 Now, by the time we consider the unification involving `s2', we
9184 already know that we must have `f<0, 0, 0>'. But, even though
9185 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9186 because there are two ways to unify base classes of S<0, 1, 2>
9187 with S<I, I, I>. If we kept the already deduced knowledge, we
9188 would reject the possibility I=1. */
9189 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9191 /* If unification failed, we're done. */
9192 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9193 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9199 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
9200 have already discovered to be satisfactory. ARG_BINFO is the binfo
9201 for the base class of ARG that we are currently examining. */
9204 get_template_base_recursive (tree tparms,
9213 tree arg = BINFO_TYPE (arg_binfo);
9215 if (!(flags & GTB_IGNORE_TYPE))
9217 tree r = try_class_unification (tparms, targs,
9220 /* If there is more than one satisfactory baseclass, then:
9224 If they yield more than one possible deduced A, the type
9228 if (r && rval && !same_type_p (r, rval))
9229 return error_mark_node;
9234 binfos = BINFO_BASETYPES (arg_binfo);
9235 n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
9237 /* Process base types. */
9238 for (i = 0; i < n_baselinks; i++)
9240 tree base_binfo = TREE_VEC_ELT (binfos, i);
9243 /* Skip this base, if we've already seen it. */
9244 if (BINFO_MARKED (base_binfo))
9248 (flags & GTB_VIA_VIRTUAL) || TREE_VIA_VIRTUAL (base_binfo);
9250 /* When searching for a non-virtual, we cannot mark virtually
9253 BINFO_MARKED (base_binfo) = 1;
9255 rval = get_template_base_recursive (tparms, targs,
9259 GTB_VIA_VIRTUAL * this_virtual);
9261 /* If we discovered more than one matching base class, we can
9263 if (rval == error_mark_node)
9264 return error_mark_node;
9270 /* Given a template type PARM and a class type ARG, find the unique
9271 base type in ARG that is an instance of PARM. We do not examine
9272 ARG itself; only its base-classes. If there is no appropriate base
9273 class, return NULL_TREE. If there is more than one, return
9274 error_mark_node. PARM may be the type of a partial specialization,
9275 as well as a plain template type. Used by unify. */
9278 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9283 my_friendly_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)), 92);
9285 arg_binfo = TYPE_BINFO (complete_type (arg));
9286 rval = get_template_base_recursive (tparms, targs,
9291 /* Since get_template_base_recursive marks the bases classes, we
9292 must unmark them here. */
9293 dfs_walk (arg_binfo, dfs_unmark, markedp, 0);
9298 /* Returns the level of DECL, which declares a template parameter. */
9301 template_decl_level (tree decl)
9303 switch (TREE_CODE (decl))
9307 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9310 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9318 /* Decide whether ARG can be unified with PARM, considering only the
9319 cv-qualifiers of each type, given STRICT as documented for unify.
9320 Returns nonzero iff the unification is OK on that basis.*/
9323 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9325 int arg_quals = cp_type_quals (arg);
9326 int parm_quals = cp_type_quals (parm);
9328 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM)
9330 /* If the cvr quals of parm will not unify with ARG, they'll be
9331 ignored in instantiation, so we have to do the same here. */
9332 if (TREE_CODE (arg) == REFERENCE_TYPE)
9333 parm_quals &= ~(TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE);
9334 if (!POINTER_TYPE_P (arg) &&
9335 TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9336 parm_quals &= ~TYPE_QUAL_RESTRICT;
9339 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9340 && (arg_quals & parm_quals) != parm_quals)
9343 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9344 && (parm_quals & arg_quals) != arg_quals)
9350 /* Takes parameters as for type_unification. Returns 0 if the
9351 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9352 bitwise or of the following flags:
9355 Require an exact match between PARM and ARG.
9356 UNIFY_ALLOW_MORE_CV_QUAL:
9357 Allow the deduced ARG to be more cv-qualified (by qualification
9358 conversion) than ARG.
9359 UNIFY_ALLOW_LESS_CV_QUAL:
9360 Allow the deduced ARG to be less cv-qualified than ARG.
9361 UNIFY_ALLOW_DERIVED:
9362 Allow the deduced ARG to be a template base class of ARG,
9363 or a pointer to a template base class of the type pointed to by
9365 UNIFY_ALLOW_INTEGER:
9366 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9367 case for more information.
9368 UNIFY_ALLOW_OUTER_LEVEL:
9369 This is the outermost level of a deduction. Used to determine validity
9370 of qualification conversions. A valid qualification conversion must
9371 have const qualified pointers leading up to the inner type which
9372 requires additional CV quals, except at the outer level, where const
9373 is not required [conv.qual]. It would be normal to set this flag in
9374 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9375 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9376 This is the outermost level of a deduction, and PARM can be more CV
9377 qualified at this point.
9378 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9379 This is the outermost level of a deduction, and PARM can be less CV
9380 qualified at this point.
9381 UNIFY_ALLOW_MAX_CORRECTION:
9382 This is an INTEGER_TYPE's maximum value. Used if the range may
9383 have been derived from a size specification, such as an array size.
9384 If the size was given by a nontype template parameter N, the maximum
9385 value will have the form N-1. The flag says that we can (and indeed
9386 must) unify N with (ARG + 1), an exception to the normal rules on
9390 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9395 int strict_in = strict;
9397 /* I don't think this will do the right thing with respect to types.
9398 But the only case I've seen it in so far has been array bounds, where
9399 signedness is the only information lost, and I think that will be
9401 while (TREE_CODE (parm) == NOP_EXPR)
9402 parm = TREE_OPERAND (parm, 0);
9404 if (arg == error_mark_node)
9406 if (arg == unknown_type_node)
9407 /* We can't deduce anything from this, but we might get all the
9408 template args from other function args. */
9411 /* If PARM uses template parameters, then we can't bail out here,
9412 even if ARG == PARM, since we won't record unifications for the
9413 template parameters. We might need them if we're trying to
9414 figure out which of two things is more specialized. */
9415 if (arg == parm && !uses_template_parms (parm))
9418 /* Immediately reject some pairs that won't unify because of
9419 cv-qualification mismatches. */
9420 if (TREE_CODE (arg) == TREE_CODE (parm)
9422 /* It is the elements of the array which hold the cv quals of an array
9423 type, and the elements might be template type parms. We'll check
9425 && TREE_CODE (arg) != ARRAY_TYPE
9426 /* We check the cv-qualifiers when unifying with template type
9427 parameters below. We want to allow ARG `const T' to unify with
9428 PARM `T' for example, when computing which of two templates
9429 is more specialized, for example. */
9430 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9431 && !check_cv_quals_for_unify (strict_in, arg, parm))
9434 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9435 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9436 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9437 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9438 strict &= ~UNIFY_ALLOW_DERIVED;
9439 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9440 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9441 strict &= ~UNIFY_ALLOW_MAX_CORRECTION;
9443 switch (TREE_CODE (parm))
9447 case UNBOUND_CLASS_TEMPLATE:
9448 /* In a type which contains a nested-name-specifier, template
9449 argument values cannot be deduced for template parameters used
9450 within the nested-name-specifier. */
9453 case TEMPLATE_TYPE_PARM:
9454 case TEMPLATE_TEMPLATE_PARM:
9455 case BOUND_TEMPLATE_TEMPLATE_PARM:
9456 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9458 if (TEMPLATE_TYPE_LEVEL (parm)
9459 != template_decl_level (tparm))
9460 /* The PARM is not one we're trying to unify. Just check
9461 to see if it matches ARG. */
9462 return (TREE_CODE (arg) == TREE_CODE (parm)
9463 && same_type_p (parm, arg)) ? 0 : 1;
9464 idx = TEMPLATE_TYPE_IDX (parm);
9465 targ = TREE_VEC_ELT (targs, idx);
9466 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9468 /* Check for mixed types and values. */
9469 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9470 && TREE_CODE (tparm) != TYPE_DECL)
9471 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9472 && TREE_CODE (tparm) != TEMPLATE_DECL))
9475 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9477 /* ARG must be constructed from a template class or a template
9478 template parameter. */
9479 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9480 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9484 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9485 tree parmvec = TYPE_TI_ARGS (parm);
9486 tree argvec = TYPE_TI_ARGS (arg);
9488 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9491 /* The parameter and argument roles have to be switched here
9492 in order to handle default arguments properly. For example,
9493 template<template <class> class TT> void f(TT<int>)
9494 should be able to accept vector<int> which comes from
9495 template <class T, class Allocator = allocator>
9498 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9502 /* Deduce arguments T, i from TT<T> or TT<i>.
9503 We check each element of PARMVEC and ARGVEC individually
9504 rather than the whole TREE_VEC since they can have
9505 different number of elements. */
9507 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9509 tree t = TREE_VEC_ELT (parmvec, i);
9511 if (unify (tparms, targs, t,
9512 TREE_VEC_ELT (argvec, i),
9517 arg = TYPE_TI_TEMPLATE (arg);
9519 /* Fall through to deduce template name. */
9522 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9523 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9525 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9527 /* Simple cases: Value already set, does match or doesn't. */
9528 if (targ != NULL_TREE && template_args_equal (targ, arg))
9535 /* If ARG is an offset type, we're trying to unify '*T' with
9536 'U C::*', which is ill-formed. See the comment in the
9537 POINTER_TYPE case about this ugliness. */
9538 if (TREE_CODE (arg) == OFFSET_TYPE)
9541 /* If PARM is `const T' and ARG is only `int', we don't have
9542 a match unless we are allowing additional qualification.
9543 If ARG is `const int' and PARM is just `T' that's OK;
9544 that binds `const int' to `T'. */
9545 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
9549 /* Consider the case where ARG is `const volatile int' and
9550 PARM is `const T'. Then, T should be `volatile int'. */
9551 arg = cp_build_qualified_type_real
9552 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
9553 if (arg == error_mark_node)
9556 /* Simple cases: Value already set, does match or doesn't. */
9557 if (targ != NULL_TREE && same_type_p (targ, arg))
9562 /* Make sure that ARG is not a variable-sized array. (Note
9563 that were talking about variable-sized arrays (like
9564 `int[n]'), rather than arrays of unknown size (like
9565 `int[]').) We'll get very confused by such a type since
9566 the bound of the array will not be computable in an
9567 instantiation. Besides, such types are not allowed in
9568 ISO C++, so we can do as we please here. */
9569 if (variably_modified_type_p (arg))
9573 TREE_VEC_ELT (targs, idx) = arg;
9576 case TEMPLATE_PARM_INDEX:
9577 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9579 if (TEMPLATE_PARM_LEVEL (parm)
9580 != template_decl_level (tparm))
9581 /* The PARM is not one we're trying to unify. Just check
9582 to see if it matches ARG. */
9583 return !(TREE_CODE (arg) == TREE_CODE (parm)
9584 && cp_tree_equal (parm, arg));
9586 idx = TEMPLATE_PARM_IDX (parm);
9587 targ = TREE_VEC_ELT (targs, idx);
9590 return !cp_tree_equal (targ, arg);
9592 /* [temp.deduct.type] If, in the declaration of a function template
9593 with a non-type template-parameter, the non-type
9594 template-parameter is used in an expression in the function
9595 parameter-list and, if the corresponding template-argument is
9596 deduced, the template-argument type shall match the type of the
9597 template-parameter exactly, except that a template-argument
9598 deduced from an array bound may be of any integral type.
9599 The non-type parameter might use already deduced type parameters. */
9600 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
9601 if (!TREE_TYPE (arg))
9602 /* Template-parameter dependent expression. Just accept it for now.
9603 It will later be processed in convert_template_argument. */
9605 else if (same_type_p (TREE_TYPE (arg), tparm))
9607 else if ((strict & UNIFY_ALLOW_INTEGER)
9608 && (TREE_CODE (tparm) == INTEGER_TYPE
9609 || TREE_CODE (tparm) == BOOLEAN_TYPE))
9611 else if (uses_template_parms (tparm))
9612 /* We haven't deduced the type of this parameter yet. Try again
9618 TREE_VEC_ELT (targs, idx) = arg;
9623 if (TREE_CODE (arg) != POINTER_TYPE)
9626 /* [temp.deduct.call]
9628 A can be another pointer or pointer to member type that can
9629 be converted to the deduced A via a qualification
9630 conversion (_conv.qual_).
9632 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
9633 This will allow for additional cv-qualification of the
9634 pointed-to types if appropriate. */
9636 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
9637 /* The derived-to-base conversion only persists through one
9638 level of pointers. */
9639 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
9641 if (TREE_CODE (TREE_TYPE (parm)) == OFFSET_TYPE
9642 && TREE_CODE (TREE_TYPE (arg)) == OFFSET_TYPE)
9644 /* Avoid getting confused about cv-quals; don't recurse here.
9645 Pointers to members should really be just OFFSET_TYPE, not
9646 this two-level nonsense... */
9648 parm = TREE_TYPE (parm);
9649 arg = TREE_TYPE (arg);
9653 return unify (tparms, targs, TREE_TYPE (parm),
9654 TREE_TYPE (arg), strict);
9657 case REFERENCE_TYPE:
9658 if (TREE_CODE (arg) != REFERENCE_TYPE)
9660 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9661 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9664 if (TREE_CODE (arg) != ARRAY_TYPE)
9666 if ((TYPE_DOMAIN (parm) == NULL_TREE)
9667 != (TYPE_DOMAIN (arg) == NULL_TREE))
9669 if (TYPE_DOMAIN (parm) != NULL_TREE
9670 && unify (tparms, targs, TYPE_DOMAIN (parm),
9671 TYPE_DOMAIN (arg), UNIFY_ALLOW_NONE) != 0)
9673 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9674 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9682 if (TREE_CODE (arg) != TREE_CODE (parm))
9685 if (TREE_CODE (parm) == INTEGER_TYPE
9686 && TREE_CODE (TYPE_MAX_VALUE (parm)) != INTEGER_CST)
9688 if (TYPE_MIN_VALUE (parm) && TYPE_MIN_VALUE (arg)
9689 && unify (tparms, targs, TYPE_MIN_VALUE (parm),
9690 TYPE_MIN_VALUE (arg), UNIFY_ALLOW_INTEGER))
9692 if (TYPE_MAX_VALUE (parm) && TYPE_MAX_VALUE (arg)
9693 && unify (tparms, targs, TYPE_MAX_VALUE (parm),
9694 TYPE_MAX_VALUE (arg),
9695 UNIFY_ALLOW_INTEGER | UNIFY_ALLOW_MAX_CORRECTION))
9698 /* We have already checked cv-qualification at the top of the
9700 else if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
9703 /* As far as unification is concerned, this wins. Later checks
9704 will invalidate it if necessary. */
9707 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
9708 /* Type INTEGER_CST can come from ordinary constant template args. */
9710 while (TREE_CODE (arg) == NOP_EXPR)
9711 arg = TREE_OPERAND (arg, 0);
9713 if (TREE_CODE (arg) != INTEGER_CST)
9715 return !tree_int_cst_equal (parm, arg);
9720 if (TREE_CODE (arg) != TREE_VEC)
9722 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
9724 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
9725 if (unify (tparms, targs,
9726 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
9734 if (TREE_CODE (arg) != TREE_CODE (parm))
9737 if (TYPE_PTRMEMFUNC_P (parm))
9739 if (!TYPE_PTRMEMFUNC_P (arg))
9742 return unify (tparms, targs,
9743 TYPE_PTRMEMFUNC_FN_TYPE (parm),
9744 TYPE_PTRMEMFUNC_FN_TYPE (arg),
9748 if (CLASSTYPE_TEMPLATE_INFO (parm))
9752 if (strict_in & UNIFY_ALLOW_DERIVED)
9754 /* First, we try to unify the PARM and ARG directly. */
9755 t = try_class_unification (tparms, targs,
9760 /* Fallback to the special case allowed in
9763 If P is a class, and P has the form
9764 template-id, then A can be a derived class of
9765 the deduced A. Likewise, if P is a pointer to
9766 a class of the form template-id, A can be a
9767 pointer to a derived class pointed to by the
9769 t = get_template_base (tparms, targs,
9772 if (! t || t == error_mark_node)
9776 else if (CLASSTYPE_TEMPLATE_INFO (arg)
9777 && (CLASSTYPE_TI_TEMPLATE (parm)
9778 == CLASSTYPE_TI_TEMPLATE (arg)))
9779 /* Perhaps PARM is something like S<U> and ARG is S<int>.
9780 Then, we should unify `int' and `U'. */
9783 /* There's no chance of unification succeeding. */
9786 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
9787 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
9789 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
9795 if (TREE_CODE (arg) != TREE_CODE (parm))
9798 if (unify (tparms, targs, TREE_TYPE (parm),
9799 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
9801 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
9802 TYPE_ARG_TYPES (arg), 1,
9803 DEDUCE_EXACT, 0, -1);
9807 if (TREE_CODE (arg) != OFFSET_TYPE)
9809 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
9810 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
9812 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9816 if (DECL_TEMPLATE_PARM_P (parm))
9817 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
9818 if (arg != decl_constant_value (parm))
9823 /* Matched cases are handled by the ARG == PARM test above. */
9827 if (tree_int_cst_equal (TREE_OPERAND (parm, 1), integer_one_node)
9828 && (strict_in & UNIFY_ALLOW_MAX_CORRECTION))
9830 /* We handle this case specially, since it comes up with
9831 arrays. In particular, something like:
9833 template <int N> void f(int (&x)[N]);
9835 Here, we are trying to unify the range type, which
9836 looks like [0 ... (N - 1)]. */
9838 t1 = TREE_OPERAND (parm, 0);
9839 t2 = TREE_OPERAND (parm, 1);
9841 t = fold (build (PLUS_EXPR, integer_type_node, arg, t2));
9843 return unify (tparms, targs, t1, t, strict);
9845 /* else fall through */
9848 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (parm))))
9851 /* We're looking at an expression. This can happen with
9855 void foo(S<I>, S<I + 2>);
9857 This is a "nondeduced context":
9861 The nondeduced contexts are:
9863 --A type that is a template-id in which one or more of
9864 the template-arguments is an expression that references
9865 a template-parameter.
9867 In these cases, we assume deduction succeeded, but don't
9868 actually infer any unifications. */
9870 if (!uses_template_parms (parm)
9871 && !template_args_equal (parm, arg))
9877 sorry ("use of `%s' in template type unification",
9878 tree_code_name [(int) TREE_CODE (parm)]);
9884 /* Called if RESULT is explicitly instantiated, or is a member of an
9885 explicitly instantiated class, or if using -frepo and the
9886 instantiation of RESULT has been assigned to this file. */
9889 mark_decl_instantiated (tree result, int extern_p)
9891 /* We used to set this unconditionally; we moved that to
9892 do_decl_instantiation so it wouldn't get set on members of
9893 explicit class template instantiations. But we still need to set
9894 it here for the 'extern template' case in order to suppress
9895 implicit instantiations. */
9897 SET_DECL_EXPLICIT_INSTANTIATION (result);
9899 /* If this entity has already been written out, it's too late to
9900 make any modifications. */
9901 if (TREE_ASM_WRITTEN (result))
9904 if (TREE_CODE (result) != FUNCTION_DECL)
9905 /* The TREE_PUBLIC flag for function declarations will have been
9906 set correctly by tsubst. */
9907 TREE_PUBLIC (result) = 1;
9909 /* This might have been set by an earlier implicit instantiation. */
9910 DECL_COMDAT (result) = 0;
9914 DECL_INTERFACE_KNOWN (result) = 1;
9915 DECL_NOT_REALLY_EXTERN (result) = 1;
9917 /* Always make artificials weak. */
9918 if (DECL_ARTIFICIAL (result) && flag_weak)
9919 comdat_linkage (result);
9920 /* For WIN32 we also want to put explicit instantiations in
9921 linkonce sections. */
9922 else if (TREE_PUBLIC (result))
9923 maybe_make_one_only (result);
9926 if (TREE_CODE (result) == FUNCTION_DECL)
9930 /* Given two function templates PAT1 and PAT2, return:
9932 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
9934 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
9935 -1 if PAT2 is more specialized than PAT1.
9936 0 if neither is more specialized.
9938 LEN is passed through to fn_type_unification. */
9941 more_specialized (tree pat1, tree pat2, int deduce, int len)
9946 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
9947 NULL_TREE, 0, deduce, len);
9951 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
9952 NULL_TREE, 0, deduce, len);
9959 /* Given two class template specialization list nodes PAT1 and PAT2, return:
9961 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
9962 -1 if PAT2 is more specialized than PAT1.
9963 0 if neither is more specialized. */
9966 more_specialized_class (tree pat1, tree pat2)
9971 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
9972 TREE_PURPOSE (pat2));
9976 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
9977 TREE_PURPOSE (pat1));
9984 /* Return the template arguments that will produce the function signature
9985 DECL from the function template FN, with the explicit template
9986 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
9987 also match. Return NULL_TREE if no satisfactory arguments could be
9988 found. DEDUCE and LEN are passed through to fn_type_unification. */
9991 get_bindings_real (tree fn,
9998 int ntparms = DECL_NTPARMS (fn);
9999 tree targs = make_tree_vec (ntparms);
10001 tree decl_arg_types;
10004 /* Substitute the explicit template arguments into the type of DECL.
10005 The call to fn_type_unification will handle substitution into the
10007 decl_type = TREE_TYPE (decl);
10008 if (explicit_args && uses_template_parms (decl_type))
10011 tree converted_args;
10013 if (DECL_TEMPLATE_INFO (decl))
10014 tmpl = DECL_TI_TEMPLATE (decl);
10016 /* We can get here for some invalid specializations. */
10020 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10021 explicit_args, NULL_TREE,
10022 tf_none, /*require_all_arguments=*/0));
10023 if (converted_args == error_mark_node)
10026 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10027 if (decl_type == error_mark_node)
10031 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10032 /* Never do unification on the 'this' parameter. */
10033 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10034 decl_arg_types = TREE_CHAIN (decl_arg_types);
10036 i = fn_type_unification (fn, explicit_args, targs,
10038 (check_rettype || DECL_CONV_FN_P (fn)
10039 ? TREE_TYPE (decl_type) : NULL_TREE),
10048 /* For most uses, we want to check the return type. */
10051 get_bindings (tree fn, tree decl, tree explicit_args)
10053 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10056 /* But for resolve_overloaded_unification, we only care about the parameter
10060 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10062 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10065 /* Return the innermost template arguments that, when applied to a
10066 template specialization whose innermost template parameters are
10067 TPARMS, and whose specialization arguments are PARMS, yield the
10070 For example, suppose we have:
10072 template <class T, class U> struct S {};
10073 template <class T> struct S<T*, int> {};
10075 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10076 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10077 int}. The resulting vector will be {double}, indicating that `T'
10078 is bound to `double'. */
10081 get_class_bindings (tree tparms, tree parms, tree args)
10083 int i, ntparms = TREE_VEC_LENGTH (tparms);
10084 tree vec = make_tree_vec (ntparms);
10086 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10090 for (i = 0; i < ntparms; ++i)
10091 if (! TREE_VEC_ELT (vec, i))
10094 if (verify_class_unification (vec, parms, args))
10100 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10101 Pick the most specialized template, and return the corresponding
10102 instantiation, or if there is no corresponding instantiation, the
10103 template itself. If there is no most specialized template,
10104 error_mark_node is returned. If there are no templates at all,
10105 NULL_TREE is returned. */
10108 most_specialized_instantiation (tree instantiations)
10113 if (!instantiations)
10116 champ = instantiations;
10117 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10119 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10127 fn = TREE_CHAIN (fn);
10129 return error_mark_node;
10135 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10137 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10140 return error_mark_node;
10143 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10146 /* Return the most specialized of the list of templates in FNS that can
10147 produce an instantiation matching DECL, given the explicit template
10148 arguments EXPLICIT_ARGS. */
10151 most_specialized (tree fns, tree decl, tree explicit_args)
10153 tree candidates = NULL_TREE;
10156 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10158 tree candidate = TREE_VALUE (fn);
10160 args = get_bindings (candidate, decl, explicit_args);
10162 candidates = tree_cons (NULL_TREE, candidate, candidates);
10165 return most_specialized_instantiation (candidates);
10168 /* If DECL is a specialization of some template, return the most
10169 general such template. Otherwise, returns NULL_TREE.
10171 For example, given:
10173 template <class T> struct S { template <class U> void f(U); };
10175 if TMPL is `template <class U> void S<int>::f(U)' this will return
10176 the full template. This function will not trace past partial
10177 specializations, however. For example, given in addition:
10179 template <class T> struct S<T*> { template <class U> void f(U); };
10181 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10182 `template <class T> template <class U> S<T*>::f(U)'. */
10185 most_general_template (tree decl)
10187 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10188 an immediate specialization. */
10189 if (TREE_CODE (decl) == FUNCTION_DECL)
10191 if (DECL_TEMPLATE_INFO (decl)) {
10192 decl = DECL_TI_TEMPLATE (decl);
10194 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10195 template friend. */
10196 if (TREE_CODE (decl) != TEMPLATE_DECL)
10202 /* Look for more and more general templates. */
10203 while (DECL_TEMPLATE_INFO (decl))
10205 /* The DECL_TI_TEMPLATE can be a LOOKUP_EXPR or IDENTIFIER_NODE
10206 in some cases. (See cp-tree.h for details.) */
10207 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10210 if (CLASS_TYPE_P (TREE_TYPE (decl))
10211 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10214 /* Stop if we run into an explicitly specialized class template. */
10215 if (!DECL_NAMESPACE_SCOPE_P (decl)
10216 && DECL_CONTEXT (decl)
10217 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10220 decl = DECL_TI_TEMPLATE (decl);
10226 /* Return the most specialized of the class template specializations
10227 of TMPL which can produce an instantiation matching ARGS, or
10228 error_mark_node if the choice is ambiguous. */
10231 most_specialized_class (tree tmpl, tree args)
10233 tree list = NULL_TREE;
10238 tmpl = most_general_template (tmpl);
10239 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10242 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10245 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10246 TREE_TYPE (list) = TREE_TYPE (t);
10255 t = TREE_CHAIN (t);
10256 for (; t; t = TREE_CHAIN (t))
10258 fate = more_specialized_class (champ, t);
10265 t = TREE_CHAIN (t);
10267 return error_mark_node;
10273 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10275 fate = more_specialized_class (champ, t);
10277 return error_mark_node;
10283 /* Explicitly instantiate DECL. */
10286 do_decl_instantiation (tree decl, tree storage)
10288 tree result = NULL_TREE;
10292 /* An error occurred, for which grokdeclarator has already issued
10293 an appropriate message. */
10295 else if (! DECL_LANG_SPECIFIC (decl))
10297 error ("explicit instantiation of non-template `%#D'", decl);
10300 else if (TREE_CODE (decl) == VAR_DECL)
10302 /* There is an asymmetry here in the way VAR_DECLs and
10303 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10304 the latter, the DECL we get back will be marked as a
10305 template instantiation, and the appropriate
10306 DECL_TEMPLATE_INFO will be set up. This does not happen for
10307 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10308 should handle VAR_DECLs as it currently handles
10310 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10311 if (!result || TREE_CODE (result) != VAR_DECL)
10313 error ("no matching template for `%D' found", decl);
10317 else if (TREE_CODE (decl) != FUNCTION_DECL)
10319 error ("explicit instantiation of `%#D'", decl);
10325 /* Check for various error cases. Note that if the explicit
10326 instantiation is valid the RESULT will currently be marked as an
10327 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10328 until we get here. */
10330 if (DECL_TEMPLATE_SPECIALIZATION (result))
10332 /* DR 259 [temp.spec].
10334 Both an explicit instantiation and a declaration of an explicit
10335 specialization shall not appear in a program unless the explicit
10336 instantiation follows a declaration of the explicit specialization.
10338 For a given set of template parameters, if an explicit
10339 instantiation of a template appears after a declaration of an
10340 explicit specialization for that template, the explicit
10341 instantiation has no effect. */
10344 else if (DECL_EXPLICIT_INSTANTIATION (result))
10348 No program shall explicitly instantiate any template more
10351 We check DECL_INTERFACE_KNOWN so as not to complain when the first
10352 instantiation was `extern' and the second is not, and EXTERN_P for
10353 the opposite case. If -frepo, chances are we already got marked
10354 as an explicit instantiation because of the repo file. */
10355 if (DECL_INTERFACE_KNOWN (result) && !extern_p && !flag_use_repository)
10356 pedwarn ("duplicate explicit instantiation of `%#D'", result);
10358 /* If we've already instantiated the template, just return now. */
10359 if (DECL_INTERFACE_KNOWN (result))
10362 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10364 error ("no matching template for `%D' found", result);
10367 else if (!DECL_TEMPLATE_INFO (result))
10369 pedwarn ("explicit instantiation of non-template `%#D'", result);
10373 if (flag_external_templates)
10376 if (storage == NULL_TREE)
10378 else if (storage == ridpointers[(int) RID_EXTERN])
10380 if (pedantic && !in_system_header)
10381 pedwarn ("ISO C++ forbids the use of `extern' on explicit instantiations");
10385 error ("storage class `%D' applied to template instantiation",
10388 SET_DECL_EXPLICIT_INSTANTIATION (result);
10389 mark_decl_instantiated (result, extern_p);
10390 repo_template_instantiated (result, extern_p);
10392 instantiate_decl (result, /*defer_ok=*/1);
10396 mark_class_instantiated (tree t, int extern_p)
10398 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10399 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10400 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10401 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10404 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10405 rest_of_type_compilation (t, 1);
10409 /* Called from do_type_instantiation through binding_table_foreach to
10410 do recursive instantiation for the type bound in ENTRY. */
10412 bt_instantiate_type_proc (binding_entry entry, void *data)
10414 tree storage = *(tree *) data;
10416 if (IS_AGGR_TYPE (entry->type)
10417 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10418 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10421 /* Perform an explicit instantiation of template class T. STORAGE, if
10422 non-null, is the RID for extern, inline or static. COMPLAIN is
10423 nonzero if this is called from the parser, zero if called recursively,
10424 since the standard is unclear (as detailed below). */
10427 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10433 if (TREE_CODE (t) == TYPE_DECL)
10436 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10438 error ("explicit instantiation of non-template type `%T'", t);
10444 /* With -fexternal-templates, explicit instantiations are treated the same
10445 as implicit ones. */
10446 if (flag_external_templates)
10449 if (!COMPLETE_TYPE_P (t))
10451 if (complain & tf_error)
10452 error ("explicit instantiation of `%#T' before definition of template",
10457 if (storage != NULL_TREE)
10459 if (pedantic && !in_system_header)
10460 pedwarn("ISO C++ forbids the use of `%s' on explicit instantiations",
10461 IDENTIFIER_POINTER (storage));
10463 if (storage == ridpointers[(int) RID_INLINE])
10465 else if (storage == ridpointers[(int) RID_EXTERN])
10467 else if (storage == ridpointers[(int) RID_STATIC])
10471 error ("storage class `%D' applied to template instantiation",
10477 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10479 /* DR 259 [temp.spec].
10481 Both an explicit instantiation and a declaration of an explicit
10482 specialization shall not appear in a program unless the explicit
10483 instantiation follows a declaration of the explicit specialization.
10485 For a given set of template parameters, if an explicit
10486 instantiation of a template appears after a declaration of an
10487 explicit specialization for that template, the explicit
10488 instantiation has no effect. */
10491 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10495 No program shall explicitly instantiate any template more
10498 If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation
10499 was `extern'. If EXTERN_P then the second is. If -frepo, chances
10500 are we already got marked as an explicit instantiation because of the
10501 repo file. All these cases are OK. */
10502 if (!CLASSTYPE_INTERFACE_ONLY (t) && !extern_p && !flag_use_repository
10503 && (complain & tf_error))
10504 pedwarn ("duplicate explicit instantiation of `%#T'", t);
10506 /* If we've already instantiated the template, just return now. */
10507 if (!CLASSTYPE_INTERFACE_ONLY (t))
10511 mark_class_instantiated (t, extern_p);
10512 repo_template_instantiated (t, extern_p);
10520 /* In contrast to implicit instantiation, where only the
10521 declarations, and not the definitions, of members are
10522 instantiated, we have here:
10526 The explicit instantiation of a class template specialization
10527 implies the instantiation of all of its members not
10528 previously explicitly specialized in the translation unit
10529 containing the explicit instantiation.
10531 Of course, we can't instantiate member template classes, since
10532 we don't have any arguments for them. Note that the standard
10533 is unclear on whether the instantiation of the members are
10534 *explicit* instantiations or not. We choose to be generous,
10535 and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow
10536 the explicit instantiation of a class where some of the members
10537 have no definition in the current translation unit. */
10540 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
10541 if (TREE_CODE (tmp) == FUNCTION_DECL
10542 && DECL_TEMPLATE_INSTANTIATION (tmp))
10544 mark_decl_instantiated (tmp, extern_p);
10545 repo_template_instantiated (tmp, extern_p);
10547 instantiate_decl (tmp, /*defer_ok=*/1);
10550 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
10551 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
10553 mark_decl_instantiated (tmp, extern_p);
10554 repo_template_instantiated (tmp, extern_p);
10556 instantiate_decl (tmp, /*defer_ok=*/1);
10559 if (CLASSTYPE_NESTED_UTDS (t))
10560 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
10561 bt_instantiate_type_proc, &storage);
10565 /* Given a function DECL, which is a specialization of TMPL, modify
10566 DECL to be a re-instantiation of TMPL with the same template
10567 arguments. TMPL should be the template into which tsubst'ing
10568 should occur for DECL, not the most general template.
10570 One reason for doing this is a scenario like this:
10573 void f(const T&, int i);
10575 void g() { f(3, 7); }
10578 void f(const T& t, const int i) { }
10580 Note that when the template is first instantiated, with
10581 instantiate_template, the resulting DECL will have no name for the
10582 first parameter, and the wrong type for the second. So, when we go
10583 to instantiate the DECL, we regenerate it. */
10586 regenerate_decl_from_template (tree decl, tree tmpl)
10588 /* The most general version of TMPL. */
10590 /* The arguments used to instantiate DECL, from the most general
10597 args = DECL_TI_ARGS (decl);
10598 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
10600 /* Unregister the specialization so that when we tsubst we will not
10601 just return DECL. We don't have to unregister DECL from TMPL
10602 because if would only be registered there if it were a partial
10603 instantiation of a specialization, which it isn't: it's a full
10605 gen_tmpl = most_general_template (tmpl);
10606 unregistered = reregister_specialization (decl, gen_tmpl,
10607 /*new_spec=*/NULL_TREE);
10609 /* If the DECL was not unregistered then something peculiar is
10610 happening: we created a specialization but did not call
10611 register_specialization for it. */
10612 my_friendly_assert (unregistered, 0);
10614 /* Make sure that we can see identifiers, and compute access
10616 push_access_scope (decl);
10618 /* Do the substitution to get the new declaration. */
10619 new_decl = tsubst (code_pattern, args, tf_error, NULL_TREE);
10621 if (TREE_CODE (decl) == VAR_DECL)
10623 /* Set up DECL_INITIAL, since tsubst doesn't. */
10624 if (!DECL_INITIALIZED_IN_CLASS_P (decl))
10625 DECL_INITIAL (new_decl) =
10626 tsubst_expr (DECL_INITIAL (code_pattern), args,
10627 tf_error, DECL_TI_TEMPLATE (decl));
10629 else if (TREE_CODE (decl) == FUNCTION_DECL)
10631 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
10633 DECL_INITIAL (new_decl) = error_mark_node;
10634 /* And don't complain about a duplicate definition. */
10635 DECL_INITIAL (decl) = NULL_TREE;
10638 pop_access_scope (decl);
10640 /* The immediate parent of the new template is still whatever it was
10641 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
10642 general template. We also reset the DECL_ASSEMBLER_NAME since
10643 tsubst always calculates the name as if the function in question
10644 were really a template instance, and sometimes, with friend
10645 functions, this is not so. See tsubst_friend_function for
10647 DECL_TI_TEMPLATE (new_decl) = DECL_TI_TEMPLATE (decl);
10648 COPY_DECL_ASSEMBLER_NAME (decl, new_decl);
10649 COPY_DECL_RTL (decl, new_decl);
10650 DECL_USE_TEMPLATE (new_decl) = DECL_USE_TEMPLATE (decl);
10652 /* Call duplicate decls to merge the old and new declarations. */
10653 duplicate_decls (new_decl, decl);
10655 /* Now, re-register the specialization. */
10656 register_specialization (decl, gen_tmpl, args);
10659 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
10660 substituted to get DECL. */
10663 template_for_substitution (tree decl)
10665 tree tmpl = DECL_TI_TEMPLATE (decl);
10667 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
10668 for the instantiation. This is not always the most general
10669 template. Consider, for example:
10672 struct S { template <class U> void f();
10673 template <> void f<int>(); };
10675 and an instantiation of S<double>::f<int>. We want TD to be the
10676 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
10677 while (/* An instantiation cannot have a definition, so we need a
10678 more general template. */
10679 DECL_TEMPLATE_INSTANTIATION (tmpl)
10680 /* We must also deal with friend templates. Given:
10682 template <class T> struct S {
10683 template <class U> friend void f() {};
10686 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
10687 so far as the language is concerned, but that's still
10688 where we get the pattern for the instantiation from. On
10689 other hand, if the definition comes outside the class, say:
10691 template <class T> struct S {
10692 template <class U> friend void f();
10694 template <class U> friend void f() {}
10696 we don't need to look any further. That's what the check for
10697 DECL_INITIAL is for. */
10698 || (TREE_CODE (decl) == FUNCTION_DECL
10699 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
10700 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
10702 /* The present template, TD, should not be a definition. If it
10703 were a definition, we should be using it! Note that we
10704 cannot restructure the loop to just keep going until we find
10705 a template with a definition, since that might go too far if
10706 a specialization was declared, but not defined. */
10707 my_friendly_assert (!(TREE_CODE (decl) == VAR_DECL
10708 && !DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl))),
10711 /* Fetch the more general template. */
10712 tmpl = DECL_TI_TEMPLATE (tmpl);
10718 /* Produce the definition of D, a _DECL generated from a template. If
10719 DEFER_OK is nonzero, then we don't have to actually do the
10720 instantiation now; we just have to do it sometime. */
10723 instantiate_decl (tree d, int defer_ok)
10725 tree tmpl = DECL_TI_TEMPLATE (d);
10732 int pattern_defined;
10734 location_t saved_loc = input_location;
10736 /* This function should only be used to instantiate templates for
10737 functions and static member variables. */
10738 my_friendly_assert (TREE_CODE (d) == FUNCTION_DECL
10739 || TREE_CODE (d) == VAR_DECL, 0);
10741 /* Variables are never deferred; if instantiation is required, they
10742 are instantiated right away. That allows for better code in the
10743 case that an expression refers to the value of the variable --
10744 if the variable has a constant value the referring expression can
10745 take advantage of that fact. */
10746 if (TREE_CODE (d) == VAR_DECL)
10749 /* Don't instantiate cloned functions. Instead, instantiate the
10750 functions they cloned. */
10751 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
10752 d = DECL_CLONED_FUNCTION (d);
10754 if (DECL_TEMPLATE_INSTANTIATED (d))
10755 /* D has already been instantiated. It might seem reasonable to
10756 check whether or not D is an explicit instantiation, and, if so,
10757 stop here. But when an explicit instantiation is deferred
10758 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
10759 is set, even though we still need to do the instantiation. */
10762 /* If we already have a specialization of this declaration, then
10763 there's no reason to instantiate it. Note that
10764 retrieve_specialization gives us both instantiations and
10765 specializations, so we must explicitly check
10766 DECL_TEMPLATE_SPECIALIZATION. */
10767 gen_tmpl = most_general_template (tmpl);
10768 gen_args = DECL_TI_ARGS (d);
10769 spec = retrieve_specialization (gen_tmpl, gen_args);
10770 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
10773 /* This needs to happen before any tsubsting. */
10774 if (! push_tinst_level (d))
10777 timevar_push (TV_PARSE);
10779 /* We may be in the middle of deferred access check. Disable
10781 push_deferring_access_checks (dk_no_deferred);
10783 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
10784 for the instantiation. */
10785 td = template_for_substitution (d);
10786 code_pattern = DECL_TEMPLATE_RESULT (td);
10788 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
10789 || DECL_TEMPLATE_SPECIALIZATION (td))
10790 /* In the case of a friend template whose definition is provided
10791 outside the class, we may have too many arguments. Drop the
10792 ones we don't need. The same is true for specializations. */
10793 args = get_innermost_template_args
10794 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
10798 if (TREE_CODE (d) == FUNCTION_DECL)
10799 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
10801 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
10803 input_location = DECL_SOURCE_LOCATION (d);
10805 if (pattern_defined)
10807 /* Let the repository code that this template definition is
10810 The repository doesn't need to know about cloned functions
10811 because they never actually show up in the object file. It
10812 does need to know about the clones; those are the symbols
10813 that the linker will be emitting error messages about. */
10814 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (d)
10815 || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (d))
10819 for (t = TREE_CHAIN (d);
10820 t && DECL_CLONED_FUNCTION_P (t);
10821 t = TREE_CHAIN (t))
10822 repo_template_used (t);
10825 repo_template_used (d);
10827 if (flag_external_templates && ! DECL_INTERFACE_KNOWN (d))
10829 if (flag_alt_external_templates)
10831 if (interface_unknown)
10832 warn_if_unknown_interface (d);
10834 else if (DECL_INTERFACE_KNOWN (code_pattern))
10836 DECL_INTERFACE_KNOWN (d) = 1;
10837 DECL_NOT_REALLY_EXTERN (d) = ! DECL_EXTERNAL (code_pattern);
10840 warn_if_unknown_interface (code_pattern);
10844 import_export_decl (d);
10849 /* Recheck the substitutions to obtain any warning messages
10850 about ignoring cv qualifiers. */
10851 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
10852 tree type = TREE_TYPE (gen);
10854 /* Make sure that we can see identifiers, and compute access
10855 correctly. D is already the target FUNCTION_DECL with the
10857 push_access_scope (d);
10859 if (TREE_CODE (gen) == FUNCTION_DECL)
10861 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
10862 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
10863 tf_error | tf_warning, d);
10864 /* Don't simply tsubst the function type, as that will give
10865 duplicate warnings about poor parameter qualifications.
10866 The function arguments are the same as the decl_arguments
10867 without the top level cv qualifiers. */
10868 type = TREE_TYPE (type);
10870 tsubst (type, gen_args, tf_error | tf_warning, d);
10872 pop_access_scope (d);
10875 if (TREE_CODE (d) == VAR_DECL && DECL_INITIALIZED_IN_CLASS_P (d)
10876 && DECL_INITIAL (d) == NULL_TREE)
10877 /* We should have set up DECL_INITIAL in instantiate_class_template. */
10879 /* Reject all external templates except inline functions. */
10880 else if (DECL_INTERFACE_KNOWN (d)
10881 && ! DECL_NOT_REALLY_EXTERN (d)
10882 && ! (TREE_CODE (d) == FUNCTION_DECL
10883 && DECL_INLINE (d)))
10885 /* Defer all other templates, unless we have been explicitly
10886 forbidden from doing so. We restore the source position here
10887 because it's used by add_pending_template. */
10888 else if (! pattern_defined || defer_ok)
10890 input_location = saved_loc;
10892 if (at_eof && !pattern_defined
10893 && DECL_EXPLICIT_INSTANTIATION (d))
10896 The definition of a non-exported function template, a
10897 non-exported member function template, or a non-exported
10898 member function or static data member of a class template
10899 shall be present in every translation unit in which it is
10900 explicitly instantiated. */
10902 ("explicit instantiation of `%D' but no definition available", d);
10904 add_pending_template (d);
10908 need_push = !global_bindings_p ();
10910 push_to_top_level ();
10912 /* Regenerate the declaration in case the template has been modified
10913 by a subsequent redeclaration. */
10914 regenerate_decl_from_template (d, td);
10916 /* We already set the file and line above. Reset them now in case
10917 they changed as a result of calling
10918 regenerate_decl_from_template. */
10919 input_location = DECL_SOURCE_LOCATION (d);
10921 if (TREE_CODE (d) == VAR_DECL)
10923 /* Clear out DECL_RTL; whatever was there before may not be right
10924 since we've reset the type of the declaration. */
10925 SET_DECL_RTL (d, NULL_RTX);
10927 DECL_IN_AGGR_P (d) = 0;
10928 import_export_decl (d);
10929 DECL_EXTERNAL (d) = ! DECL_NOT_REALLY_EXTERN (d);
10931 if (DECL_EXTERNAL (d))
10933 /* The fact that this code is executing indicates that:
10935 (1) D is a template static data member, for which a
10936 definition is available.
10938 (2) An implicit or explicit instantiation has occurred.
10940 (3) We are not going to emit a definition of the static
10941 data member at this time.
10943 This situation is peculiar, but it occurs on platforms
10944 without weak symbols when performing an implicit
10945 instantiation. There, we cannot implicitly instantiate a
10946 defined static data member in more than one translation
10947 unit, so import_export_decl marks the declaration as
10948 external; we must rely on explicit instantiation. */
10952 /* Mark D as instantiated so that recursive calls to
10953 instantiate_decl do not try to instantiate it again. */
10954 DECL_TEMPLATE_INSTANTIATED (d) = 1;
10956 (!DECL_INITIALIZED_IN_CLASS_P (d)
10957 ? DECL_INITIAL (d) : NULL_TREE),
10961 else if (TREE_CODE (d) == FUNCTION_DECL)
10963 htab_t saved_local_specializations;
10968 /* Mark D as instantiated so that recursive calls to
10969 instantiate_decl do not try to instantiate it again. */
10970 DECL_TEMPLATE_INSTANTIATED (d) = 1;
10972 /* Save away the current list, in case we are instantiating one
10973 template from within the body of another. */
10974 saved_local_specializations = local_specializations;
10976 /* Set up the list of local specializations. */
10977 local_specializations = htab_create (37,
10978 hash_local_specialization,
10979 eq_local_specializations,
10982 /* Set up context. */
10983 import_export_decl (d);
10984 start_function (NULL_TREE, d, NULL_TREE, SF_PRE_PARSED);
10986 /* Create substitution entries for the parameters. */
10987 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
10988 tmpl_parm = DECL_ARGUMENTS (subst_decl);
10989 spec_parm = DECL_ARGUMENTS (d);
10990 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
10992 register_local_specialization (spec_parm, tmpl_parm);
10993 spec_parm = skip_artificial_parms_for (d, spec_parm);
10994 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
10998 register_local_specialization (spec_parm, tmpl_parm);
10999 tmpl_parm = TREE_CHAIN (tmpl_parm);
11000 spec_parm = TREE_CHAIN (spec_parm);
11002 my_friendly_assert (!spec_parm, 20020813);
11004 /* Substitute into the body of the function. */
11005 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11006 tf_error | tf_warning, tmpl);
11008 /* We don't need the local specializations any more. */
11009 htab_delete (local_specializations);
11010 local_specializations = saved_local_specializations;
11012 /* Finish the function. */
11013 d = finish_function (0);
11014 expand_or_defer_fn (d);
11017 /* We're not deferring instantiation any more. */
11018 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11021 pop_from_top_level ();
11024 input_location = saved_loc;
11025 pop_deferring_access_checks ();
11026 pop_tinst_level ();
11028 timevar_pop (TV_PARSE);
11033 /* Run through the list of templates that we wish we could
11034 instantiate, and instantiate any we can. */
11037 instantiate_pending_templates (void)
11040 tree last = NULL_TREE;
11041 int instantiated_something = 0;
11048 t = &pending_templates;
11051 tree instantiation = TREE_VALUE (*t);
11053 reopen_tinst_level (TREE_PURPOSE (*t));
11055 if (TYPE_P (instantiation))
11059 if (!COMPLETE_TYPE_P (instantiation))
11061 instantiate_class_template (instantiation);
11062 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11063 for (fn = TYPE_METHODS (instantiation);
11065 fn = TREE_CHAIN (fn))
11066 if (! DECL_ARTIFICIAL (fn))
11067 instantiate_decl (fn, /*defer_ok=*/0);
11068 if (COMPLETE_TYPE_P (instantiation))
11070 instantiated_something = 1;
11075 if (COMPLETE_TYPE_P (instantiation))
11076 /* If INSTANTIATION has been instantiated, then we don't
11077 need to consider it again in the future. */
11078 *t = TREE_CHAIN (*t);
11082 t = &TREE_CHAIN (*t);
11087 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11088 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11090 instantiation = instantiate_decl (instantiation,
11092 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11094 instantiated_something = 1;
11099 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11100 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11101 /* If INSTANTIATION has been instantiated, then we don't
11102 need to consider it again in the future. */
11103 *t = TREE_CHAIN (*t);
11107 t = &TREE_CHAIN (*t);
11111 current_tinst_level = NULL_TREE;
11113 last_pending_template = last;
11115 while (reconsider);
11117 return instantiated_something;
11120 /* Substitute ARGVEC into T, which is a list of initializers for
11121 either base class or a non-static data member. The TREE_PURPOSEs
11122 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11123 instantiate_decl. */
11126 tsubst_initializer_list (tree t, tree argvec)
11128 tree inits = NULL_TREE;
11130 for (; t; t = TREE_CHAIN (t))
11136 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11138 decl = expand_member_init (decl);
11139 if (decl && !DECL_P (decl))
11140 in_base_initializer = 1;
11142 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11146 else if (TREE_CODE (init) == TREE_LIST)
11147 for (val = init; val; val = TREE_CHAIN (val))
11148 TREE_VALUE (val) = convert_from_reference (TREE_VALUE (val));
11149 else if (init != void_type_node)
11150 init = convert_from_reference (init);
11152 in_base_initializer = 0;
11156 init = build_tree_list (decl, init);
11157 TREE_CHAIN (init) = inits;
11164 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11167 set_current_access_from_decl (tree decl)
11169 if (TREE_PRIVATE (decl))
11170 current_access_specifier = access_private_node;
11171 else if (TREE_PROTECTED (decl))
11172 current_access_specifier = access_protected_node;
11174 current_access_specifier = access_public_node;
11177 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11178 is the instantiation (which should have been created with
11179 start_enum) and ARGS are the template arguments to use. */
11182 tsubst_enum (tree tag, tree newtag, tree args)
11186 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11190 /* Note that in a template enum, the TREE_VALUE is the
11191 CONST_DECL, not the corresponding INTEGER_CST. */
11192 value = tsubst_expr (DECL_INITIAL (TREE_VALUE (e)),
11193 args, tf_error | tf_warning,
11196 /* Give this enumeration constant the correct access. */
11197 set_current_access_from_decl (TREE_VALUE (e));
11199 /* Actually build the enumerator itself. */
11200 build_enumerator (TREE_PURPOSE (e), value, newtag);
11203 finish_enum (newtag);
11204 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11205 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11208 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11209 its type -- but without substituting the innermost set of template
11210 arguments. So, innermost set of template parameters will appear in
11214 get_mostly_instantiated_function_type (tree decl)
11222 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11223 targs = DECL_TI_ARGS (decl);
11224 tparms = DECL_TEMPLATE_PARMS (tmpl);
11225 parm_depth = TMPL_PARMS_DEPTH (tparms);
11227 /* There should be as many levels of arguments as there are levels
11229 my_friendly_assert (parm_depth == TMPL_ARGS_DEPTH (targs), 0);
11231 fn_type = TREE_TYPE (tmpl);
11233 if (parm_depth == 1)
11234 /* No substitution is necessary. */
11241 /* Replace the innermost level of the TARGS with NULL_TREEs to
11242 let tsubst know not to substitute for those parameters. */
11243 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11244 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11245 SET_TMPL_ARGS_LEVEL (partial_args, i,
11246 TMPL_ARGS_LEVEL (targs, i));
11247 SET_TMPL_ARGS_LEVEL (partial_args,
11248 TMPL_ARGS_DEPTH (targs),
11249 make_tree_vec (DECL_NTPARMS (tmpl)));
11251 /* Make sure that we can see identifiers, and compute access
11252 correctly. We can just use the context of DECL for the
11253 partial substitution here. It depends only on outer template
11254 parameters, regardless of whether the innermost level is
11255 specialized or not. */
11256 push_access_scope (decl);
11258 /* Now, do the (partial) substitution to figure out the
11259 appropriate function type. */
11260 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11262 /* Substitute into the template parameters to obtain the real
11263 innermost set of parameters. This step is important if the
11264 innermost set of template parameters contains value
11265 parameters whose types depend on outer template parameters. */
11266 TREE_VEC_LENGTH (partial_args)--;
11267 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11269 pop_access_scope (decl);
11275 /* Return truthvalue if we're processing a template different from
11276 the last one involved in diagnostics. */
11278 problematic_instantiation_changed (void)
11280 return last_template_error_tick != tinst_level_tick;
11283 /* Remember current template involved in diagnostics. */
11285 record_last_problematic_instantiation (void)
11287 last_template_error_tick = tinst_level_tick;
11291 current_instantiation (void)
11293 return current_tinst_level;
11296 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11297 type. Return zero for ok, nonzero for disallowed. Issue error and
11298 warning messages under control of COMPLAIN. */
11301 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11303 if (INTEGRAL_TYPE_P (type))
11305 else if (POINTER_TYPE_P (type))
11307 else if (TYPE_PTRMEM_P (type))
11309 else if (TYPE_PTRMEMFUNC_P (type))
11311 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11313 else if (TREE_CODE (type) == TYPENAME_TYPE)
11316 if (complain & tf_error)
11317 error ("`%#T' is not a valid type for a template constant parameter",
11322 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11323 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11326 dependent_type_p_r (tree type)
11332 A type is dependent if it is:
11334 -- a template parameter. */
11335 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11337 /* -- a qualified-id with a nested-name-specifier which contains a
11338 class-name that names a dependent type or whose unqualified-id
11339 names a dependent type. */
11340 if (TREE_CODE (type) == TYPENAME_TYPE)
11342 /* -- a cv-qualified type where the cv-unqualified type is
11344 type = TYPE_MAIN_VARIANT (type);
11345 /* -- a compound type constructed from any dependent type. */
11346 if (TYPE_PTRMEM_P (type) || TYPE_PTRMEMFUNC_P (type))
11347 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11348 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11350 else if (TREE_CODE (type) == POINTER_TYPE
11351 || TREE_CODE (type) == REFERENCE_TYPE)
11352 return dependent_type_p (TREE_TYPE (type));
11353 else if (TREE_CODE (type) == FUNCTION_TYPE
11354 || TREE_CODE (type) == METHOD_TYPE)
11358 if (dependent_type_p (TREE_TYPE (type)))
11360 for (arg_type = TYPE_ARG_TYPES (type);
11362 arg_type = TREE_CHAIN (arg_type))
11363 if (dependent_type_p (TREE_VALUE (arg_type)))
11367 /* -- an array type constructed from any dependent type or whose
11368 size is specified by a constant expression that is
11369 value-dependent. */
11370 if (TREE_CODE (type) == ARRAY_TYPE)
11372 if (TYPE_DOMAIN (type)
11373 && ((value_dependent_expression_p
11374 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11375 || (type_dependent_expression_p
11376 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11378 return dependent_type_p (TREE_TYPE (type));
11380 /* -- a template-id in which either the template name is a template
11381 parameter or any of the template arguments is a dependent type or
11382 an expression that is type-dependent or value-dependent.
11384 This language seems somewhat confused; for example, it does not
11385 discuss template template arguments. Therefore, we use the
11386 definition for dependent template arguments in [temp.dep.temp]. */
11387 if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11388 && (dependent_template_id_p
11389 (CLASSTYPE_TI_TEMPLATE (type),
11390 CLASSTYPE_TI_ARGS (type))))
11392 else if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11394 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11395 expression is not type-dependent, then it should already been
11397 if (TREE_CODE (type) == TYPEOF_TYPE)
11399 /* The standard does not specifically mention types that are local
11400 to template functions or local classes, but they should be
11401 considered dependent too. For example:
11403 template <int I> void f() {
11408 The size of `E' cannot be known until the value of `I' has been
11409 determined. Therefore, `E' must be considered dependent. */
11410 scope = TYPE_CONTEXT (type);
11411 if (scope && TYPE_P (scope))
11412 return dependent_type_p (scope);
11413 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11414 return type_dependent_expression_p (scope);
11416 /* Other types are non-dependent. */
11420 /* Returns TRUE if TYPE is dependent, in the sense of
11421 [temp.dep.type]. */
11424 dependent_type_p (tree type)
11426 /* If there are no template parameters in scope, then there can't be
11427 any dependent types. */
11428 if (!processing_template_decl)
11431 /* If the type is NULL, we have not computed a type for the entity
11432 in question; in that case, the type is dependent. */
11436 /* Erroneous types can be considered non-dependent. */
11437 if (type == error_mark_node)
11440 /* If we have not already computed the appropriate value for TYPE,
11442 if (!TYPE_DEPENDENT_P_VALID (type))
11444 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11445 TYPE_DEPENDENT_P_VALID (type) = 1;
11448 return TYPE_DEPENDENT_P (type);
11451 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11452 [temp.dep.constexpr] */
11455 value_dependent_expression_p (tree expression)
11457 if (!processing_template_decl)
11460 /* A name declared with a dependent type. */
11461 if (TREE_CODE (expression) == LOOKUP_EXPR
11462 || (DECL_P (expression)
11463 && type_dependent_expression_p (expression)))
11465 /* A non-type template parameter. */
11466 if ((TREE_CODE (expression) == CONST_DECL
11467 && DECL_TEMPLATE_PARM_P (expression))
11468 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11470 /* A constant with integral or enumeration type and is initialized
11471 with an expression that is value-dependent. */
11472 if (TREE_CODE (expression) == VAR_DECL
11473 && DECL_INITIAL (expression)
11474 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11475 && value_dependent_expression_p (DECL_INITIAL (expression)))
11477 /* These expressions are value-dependent if the type to which the
11478 cast occurs is dependent or the expression being casted is
11479 value-dependent. */
11480 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11481 || TREE_CODE (expression) == STATIC_CAST_EXPR
11482 || TREE_CODE (expression) == CONST_CAST_EXPR
11483 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11484 || TREE_CODE (expression) == CAST_EXPR)
11486 if (dependent_type_p (TREE_TYPE (expression)))
11488 /* A functional cast has a list of operands. */
11489 expression = TREE_OPERAND (expression, 0);
11490 if (TREE_CODE (expression) == TREE_LIST)
11494 if (value_dependent_expression_p (TREE_VALUE (expression)))
11496 expression = TREE_CHAIN (expression);
11498 while (expression);
11502 return value_dependent_expression_p (expression);
11504 /* A `sizeof' expression is value-dependent if the operand is
11506 if (TREE_CODE (expression) == SIZEOF_EXPR
11507 || TREE_CODE (expression) == ALIGNOF_EXPR)
11509 expression = TREE_OPERAND (expression, 0);
11510 if (TYPE_P (expression))
11511 return dependent_type_p (expression);
11512 return type_dependent_expression_p (expression);
11514 /* A constant expression is value-dependent if any subexpression is
11515 value-dependent. */
11516 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (expression))))
11518 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
11521 return (value_dependent_expression_p
11522 (TREE_OPERAND (expression, 0)));
11525 return ((value_dependent_expression_p
11526 (TREE_OPERAND (expression, 0)))
11527 || (value_dependent_expression_p
11528 (TREE_OPERAND (expression, 1))));
11532 for (i = 0; i < first_rtl_op (TREE_CODE (expression)); ++i)
11533 /* In some cases, some of the operands may be missing.
11534 (For example, in the case of PREDECREMENT_EXPR, the
11535 amount to increment by may be missing.) That doesn't
11536 make the expression dependent. */
11537 if (TREE_OPERAND (expression, i)
11538 && (value_dependent_expression_p
11539 (TREE_OPERAND (expression, i))))
11546 /* The expression is not value-dependent. */
11550 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11551 [temp.dep.expr]. */
11554 type_dependent_expression_p (tree expression)
11556 if (!processing_template_decl)
11559 if (expression == error_mark_node)
11562 /* Some expression forms are never type-dependent. */
11563 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
11564 || TREE_CODE (expression) == SIZEOF_EXPR
11565 || TREE_CODE (expression) == ALIGNOF_EXPR
11566 || TREE_CODE (expression) == TYPEID_EXPR
11567 || TREE_CODE (expression) == DELETE_EXPR
11568 || TREE_CODE (expression) == VEC_DELETE_EXPR
11569 || TREE_CODE (expression) == THROW_EXPR)
11572 /* The types of these expressions depends only on the type to which
11573 the cast occurs. */
11574 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11575 || TREE_CODE (expression) == STATIC_CAST_EXPR
11576 || TREE_CODE (expression) == CONST_CAST_EXPR
11577 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11578 || TREE_CODE (expression) == CAST_EXPR)
11579 return dependent_type_p (TREE_TYPE (expression));
11581 /* The types of these expressions depends only on the type created
11582 by the expression. */
11583 if (TREE_CODE (expression) == NEW_EXPR
11584 || TREE_CODE (expression) == VEC_NEW_EXPR)
11586 /* For NEW_EXPR tree nodes created inside a template, either
11587 the object type itself or a TREE_LIST may appear as the
11589 tree type = TREE_OPERAND (expression, 1);
11590 if (TREE_CODE (type) == TREE_LIST)
11591 /* This is an array type. We need to check array dimensions
11593 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
11594 || value_dependent_expression_p
11595 (TREE_OPERAND (TREE_VALUE (type), 1));
11597 return dependent_type_p (type);
11602 An id-expression is type-dependent if it contains a
11603 nested-name-specifier that contains a class-name that names a
11605 if (TREE_CODE (expression) == SCOPE_REF
11606 && TYPE_P (TREE_OPERAND (expression, 0)))
11611 scope = TREE_OPERAND (expression, 0);
11612 name = TREE_OPERAND (expression, 1);
11614 /* The suggested resolution to Core Issue 2 implies that if the
11615 qualifying type is the current class, then we must peek
11618 && currently_open_class (scope)
11619 && !type_dependent_expression_p (name))
11621 if (dependent_type_p (scope))
11625 if (TREE_CODE (expression) == FUNCTION_DECL
11626 && DECL_LANG_SPECIFIC (expression)
11627 && DECL_TEMPLATE_INFO (expression)
11628 && (dependent_template_id_p
11629 (DECL_TI_TEMPLATE (expression),
11630 INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
11633 if (TREE_TYPE (expression) == unknown_type_node)
11635 if (TREE_CODE (expression) == ADDR_EXPR)
11636 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
11637 if (TREE_CODE (expression) == BASELINK)
11638 expression = BASELINK_FUNCTIONS (expression);
11639 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
11641 if (any_dependent_template_arguments_p (TREE_OPERAND (expression,
11644 expression = TREE_OPERAND (expression, 0);
11646 if (TREE_CODE (expression) == OVERLOAD)
11650 if (type_dependent_expression_p (OVL_CURRENT (expression)))
11652 expression = OVL_NEXT (expression);
11659 return (dependent_type_p (TREE_TYPE (expression)));
11662 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
11663 contains a type-dependent expression. */
11666 any_type_dependent_arguments_p (tree args)
11670 tree arg = TREE_VALUE (args);
11672 if (type_dependent_expression_p (arg))
11674 args = TREE_CHAIN (args);
11679 /* Returns TRUE if the ARG (a template argument) is dependent. */
11682 dependent_template_arg_p (tree arg)
11684 if (!processing_template_decl)
11687 if (TREE_CODE (arg) == TEMPLATE_DECL
11688 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11689 return dependent_template_p (arg);
11690 else if (TYPE_P (arg))
11691 return dependent_type_p (arg);
11693 return (type_dependent_expression_p (arg)
11694 || value_dependent_expression_p (arg));
11697 /* Returns true if ARGS (a collection of template arguments) contains
11698 any dependent arguments. */
11701 any_dependent_template_arguments_p (tree args)
11706 my_friendly_assert (TREE_CODE (args) == TREE_LIST
11707 || TREE_CODE (args) == TREE_VEC,
11710 if (TREE_CODE (args) == TREE_LIST)
11714 if (dependent_template_arg_p (TREE_VALUE (args)))
11716 args = TREE_CHAIN (args);
11722 for (i = 0; i < TREE_VEC_LENGTH (args); ++i)
11723 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
11730 /* Returns TRUE if the template TMPL is dependent. */
11733 dependent_template_p (tree tmpl)
11735 /* Template template parameters are dependent. */
11736 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
11737 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
11739 /* So are qualified names that have not been looked up. */
11740 if (TREE_CODE (tmpl) == SCOPE_REF)
11742 /* So are member templates of dependent classes. */
11743 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
11744 return dependent_type_p (DECL_CONTEXT (tmpl));
11748 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
11751 dependent_template_id_p (tree tmpl, tree args)
11753 return (dependent_template_p (tmpl)
11754 || any_dependent_template_arguments_p (args));
11757 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
11758 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
11759 can be found. Note that this function peers inside uninstantiated
11760 templates and therefore should be used only in extremely limited
11764 resolve_typename_type (tree type, bool only_current_p)
11771 my_friendly_assert (TREE_CODE (type) == TYPENAME_TYPE,
11774 scope = TYPE_CONTEXT (type);
11775 name = TYPE_IDENTIFIER (type);
11777 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
11778 it first before we can figure out what NAME refers to. */
11779 if (TREE_CODE (scope) == TYPENAME_TYPE)
11780 scope = resolve_typename_type (scope, only_current_p);
11781 /* If we don't know what SCOPE refers to, then we cannot resolve the
11783 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
11784 return error_mark_node;
11785 /* If the SCOPE is a template type parameter, we have no way of
11786 resolving the name. */
11787 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
11789 /* If the SCOPE is not the current instantiation, there's no reason
11790 to look inside it. */
11791 if (only_current_p && !currently_open_class (scope))
11792 return error_mark_node;
11793 /* If SCOPE is a partial instantiation, it will not have a valid
11794 TYPE_FIELDS list, so use the original template. */
11795 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
11796 /* Enter the SCOPE so that name lookup will be resolved as if we
11797 were in the class definition. In particular, SCOPE will no
11798 longer be considered a dependent type. */
11799 push_scope (scope);
11800 /* Look up the declaration. */
11801 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
11802 /* Obtain the set of qualifiers applied to the TYPE. */
11803 quals = cp_type_quals (type);
11804 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
11805 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
11807 type = error_mark_node;
11808 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
11809 && TREE_CODE (decl) == TYPE_DECL)
11810 type = TREE_TYPE (decl);
11811 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
11812 && DECL_CLASS_TEMPLATE_P (decl))
11816 /* Obtain the template and the arguments. */
11817 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
11818 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
11819 /* Instantiate the template. */
11820 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
11821 /*entering_scope=*/0,
11825 type = error_mark_node;
11826 /* Qualify the resulting type. */
11827 if (type != error_mark_node && quals)
11828 type = cp_build_qualified_type (type, quals);
11829 /* Leave the SCOPE. */
11835 /* EXPR is an expression which is not type-dependent. Return a proxy
11836 for EXPR that can be used to compute the types of larger
11837 expressions containing EXPR. */
11840 build_non_dependent_expr (tree expr)
11842 /* Preserve null pointer constants so that the type of things like
11843 "p == 0" where "p" is a pointer can be determined. */
11844 if (null_ptr_cst_p (expr))
11846 /* Preserve OVERLOADs; the functions must be available to resolve
11848 if (TREE_CODE (expr) == OVERLOAD)
11850 /* Otherwise, build a NON_DEPENDENT_EXPR.
11852 REFERENCE_TYPEs are not stripped for expressions in templates
11853 because doing so would play havoc with mangling. Consider, for
11856 template <typename T> void f<T& g>() { g(); }
11858 In the body of "f", the expression for "g" will have
11859 REFERENCE_TYPE, even though the standard says that it should
11860 not. The reason is that we must preserve the syntactic form of
11861 the expression so that mangling (say) "f<g>" inside the body of
11862 "f" works out correctly. Therefore, the REFERENCE_TYPE is
11864 return build (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)));
11867 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
11868 Return a new TREE_LIST with the various arguments replaced with
11869 equivalent non-dependent expressions. */
11872 build_non_dependent_args (tree args)
11877 new_args = NULL_TREE;
11878 for (a = args; a; a = TREE_CHAIN (a))
11879 new_args = tree_cons (NULL_TREE,
11880 build_non_dependent_expr (TREE_VALUE (a)),
11882 return nreverse (new_args);
11885 #include "gt-cp-pt.h"