1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
37 #include "tree-inline.h"
44 #include "tree-iterator.h"
46 /* The type of functions taking a tree, and some additional data, and
48 typedef int (*tree_fn_t) (tree, void*);
50 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
51 instantiations have been deferred, either because their definitions
52 were not yet available, or because we were putting off doing the work.
53 The TREE_PURPOSE of each entry is either a DECL (for a function or
54 static data member), or a TYPE (for a class) indicating what we are
55 hoping to instantiate. The TREE_VALUE is not used. */
56 static GTY(()) tree pending_templates;
57 static GTY(()) tree last_pending_template;
59 int processing_template_parmlist;
60 static int template_header_count;
62 static GTY(()) tree saved_trees;
63 static GTY(()) varray_type inline_parm_levels;
64 static size_t inline_parm_levels_used;
66 static GTY(()) tree current_tinst_level;
68 static GTY(()) tree saved_access_scope;
70 /* A map from local variable declarations in the body of the template
71 presently being instantiated to the corresponding instantiated
73 static htab_t local_specializations;
75 #define UNIFY_ALLOW_NONE 0
76 #define UNIFY_ALLOW_MORE_CV_QUAL 1
77 #define UNIFY_ALLOW_LESS_CV_QUAL 2
78 #define UNIFY_ALLOW_DERIVED 4
79 #define UNIFY_ALLOW_INTEGER 8
80 #define UNIFY_ALLOW_OUTER_LEVEL 16
81 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
82 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
83 #define UNIFY_ALLOW_MAX_CORRECTION 128
85 #define GTB_VIA_VIRTUAL 1 /* The base class we are examining is
86 virtual, or a base class of a virtual
88 #define GTB_IGNORE_TYPE 2 /* We don't need to try to unify the current
89 type with the desired type. */
91 static void push_access_scope (tree);
92 static void pop_access_scope (tree);
93 static int resolve_overloaded_unification (tree, tree, tree, tree,
94 unification_kind_t, int);
95 static int try_one_overload (tree, tree, tree, tree, tree,
96 unification_kind_t, int, bool);
97 static int unify (tree, tree, tree, tree, int);
98 static void add_pending_template (tree);
99 static void reopen_tinst_level (tree);
100 static tree classtype_mangled_name (tree);
101 static char* mangle_class_name_for_template (const char *, tree, tree);
102 static tree tsubst_initializer_list (tree, tree);
103 static tree get_class_bindings (tree, tree, tree);
104 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
105 static void tsubst_enum (tree, tree, tree);
106 static tree add_to_template_args (tree, tree);
107 static tree add_outermost_template_args (tree, tree);
108 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
109 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
110 static int type_unification_real (tree, tree, tree, tree,
111 int, unification_kind_t, int, int);
112 static void note_template_header (int);
113 static tree convert_nontype_argument (tree, tree);
114 static tree convert_template_argument (tree, tree, tree,
115 tsubst_flags_t, int, tree);
116 static tree get_bindings_overload (tree, tree, tree);
117 static int for_each_template_parm (tree, tree_fn_t, void*, htab_t);
118 static tree build_template_parm_index (int, int, int, tree, tree);
119 static int inline_needs_template_parms (tree);
120 static void push_inline_template_parms_recursive (tree, int);
121 static tree retrieve_specialization (tree, tree);
122 static tree retrieve_local_specialization (tree);
123 static tree register_specialization (tree, tree, tree);
124 static void register_local_specialization (tree, tree);
125 static tree reduce_template_parm_level (tree, tree, int);
126 static tree build_template_decl (tree, tree);
127 static int mark_template_parm (tree, void *);
128 static int template_parm_this_level_p (tree, void *);
129 static tree tsubst_friend_function (tree, tree);
130 static tree tsubst_friend_class (tree, tree);
131 static int can_complete_type_without_circularity (tree);
132 static tree get_bindings (tree, tree, tree);
133 static tree get_bindings_real (tree, tree, tree, int, int, int);
134 static int template_decl_level (tree);
135 static int check_cv_quals_for_unify (int, tree, tree);
136 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
137 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
138 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
139 static void regenerate_decl_from_template (tree, tree);
140 static tree most_specialized (tree, tree, tree);
141 static tree most_specialized_class (tree, tree);
142 static int template_class_depth_real (tree, int);
143 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
144 static tree tsubst_decl (tree, tree, tree, tsubst_flags_t);
145 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
146 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
147 static void check_specialization_scope (void);
148 static tree process_partial_specialization (tree);
149 static void set_current_access_from_decl (tree);
150 static void check_default_tmpl_args (tree, tree, int, int);
151 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
152 static tree get_template_base_recursive (tree, tree, tree, tree, tree, int);
153 static tree get_template_base (tree, tree, tree, tree);
154 static int verify_class_unification (tree, tree, tree);
155 static tree try_class_unification (tree, tree, tree, tree);
156 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
158 static tree determine_specialization (tree, tree, tree *, int, int);
159 static int template_args_equal (tree, tree);
160 static void tsubst_default_arguments (tree);
161 static tree for_each_template_parm_r (tree *, int *, void *);
162 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
163 static void copy_default_args_to_explicit_spec (tree);
164 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
165 static int eq_local_specializations (const void *, const void *);
166 static bool dependent_type_p_r (tree);
167 static tree tsubst (tree, tree, tsubst_flags_t, tree);
168 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
169 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
171 /* Make the current scope suitable for access checking when we are
172 processing T. T can be FUNCTION_DECL for instantiated function
173 template, or VAR_DECL for static member variable (need by
174 instantiate_decl). */
177 push_access_scope (tree t)
179 my_friendly_assert (TREE_CODE (t) == FUNCTION_DECL
180 || TREE_CODE (t) == VAR_DECL,
183 if (DECL_CLASS_SCOPE_P (t))
184 push_nested_class (DECL_CONTEXT (t));
186 push_to_top_level ();
188 if (TREE_CODE (t) == FUNCTION_DECL)
190 saved_access_scope = tree_cons
191 (NULL_TREE, current_function_decl, saved_access_scope);
192 current_function_decl = t;
196 /* Restore the scope set up by push_access_scope. T is the node we
200 pop_access_scope (tree t)
202 if (TREE_CODE (t) == FUNCTION_DECL)
204 current_function_decl = TREE_VALUE (saved_access_scope);
205 saved_access_scope = TREE_CHAIN (saved_access_scope);
208 if (DECL_CLASS_SCOPE_P (t))
211 pop_from_top_level ();
214 /* Do any processing required when DECL (a member template
215 declaration) is finished. Returns the TEMPLATE_DECL corresponding
216 to DECL, unless it is a specialization, in which case the DECL
217 itself is returned. */
220 finish_member_template_decl (tree decl)
222 if (decl == error_mark_node)
223 return error_mark_node;
225 my_friendly_assert (DECL_P (decl), 20020812);
227 if (TREE_CODE (decl) == TYPE_DECL)
231 type = TREE_TYPE (decl);
232 if (IS_AGGR_TYPE (type)
233 && CLASSTYPE_TEMPLATE_INFO (type)
234 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
236 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
237 check_member_template (tmpl);
242 else if (TREE_CODE (decl) == FIELD_DECL)
243 error ("data member `%D' cannot be a member template", decl);
244 else if (DECL_TEMPLATE_INFO (decl))
246 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
248 check_member_template (DECL_TI_TEMPLATE (decl));
249 return DECL_TI_TEMPLATE (decl);
255 error ("invalid member template declaration `%D'", decl);
257 return error_mark_node;
260 /* Returns the template nesting level of the indicated class TYPE.
270 A<T>::B<U> has depth two, while A<T> has depth one.
271 Both A<T>::B<int> and A<int>::B<U> have depth one, if
272 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
275 This function is guaranteed to return 0 if passed NULL_TREE so
276 that, for example, `template_class_depth (current_class_type)' is
280 template_class_depth_real (tree type, int count_specializations)
285 type && TREE_CODE (type) != NAMESPACE_DECL;
286 type = (TREE_CODE (type) == FUNCTION_DECL)
287 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
289 if (TREE_CODE (type) != FUNCTION_DECL)
291 if (CLASSTYPE_TEMPLATE_INFO (type)
292 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
293 && ((count_specializations
294 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
295 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
300 if (DECL_TEMPLATE_INFO (type)
301 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
302 && ((count_specializations
303 && DECL_TEMPLATE_SPECIALIZATION (type))
304 || uses_template_parms (DECL_TI_ARGS (type))))
312 /* Returns the template nesting level of the indicated class TYPE.
313 Like template_class_depth_real, but instantiations do not count in
317 template_class_depth (tree type)
319 return template_class_depth_real (type, /*count_specializations=*/0);
322 /* Returns 1 if processing DECL as part of do_pending_inlines
323 needs us to push template parms. */
326 inline_needs_template_parms (tree decl)
328 if (! DECL_TEMPLATE_INFO (decl))
331 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
332 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
335 /* Subroutine of maybe_begin_member_template_processing.
336 Push the template parms in PARMS, starting from LEVELS steps into the
337 chain, and ending at the beginning, since template parms are listed
341 push_inline_template_parms_recursive (tree parmlist, int levels)
343 tree parms = TREE_VALUE (parmlist);
347 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
349 ++processing_template_decl;
350 current_template_parms
351 = tree_cons (size_int (processing_template_decl),
352 parms, current_template_parms);
353 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
355 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
357 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
359 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
360 my_friendly_assert (DECL_P (parm), 0);
362 switch (TREE_CODE (parm))
371 /* Make a CONST_DECL as is done in process_template_parm.
372 It is ugly that we recreate this here; the original
373 version built in process_template_parm is no longer
375 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
377 DECL_ARTIFICIAL (decl) = 1;
378 TREE_CONSTANT (decl) = 1;
379 TREE_INVARIANT (decl) = 1;
380 TREE_READONLY (decl) = 1;
381 DECL_INITIAL (decl) = DECL_INITIAL (parm);
382 SET_DECL_TEMPLATE_PARM_P (decl);
393 /* Restore the template parameter context for a member template or
394 a friend template defined in a class definition. */
397 maybe_begin_member_template_processing (tree decl)
402 if (inline_needs_template_parms (decl))
404 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
405 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
407 if (DECL_TEMPLATE_SPECIALIZATION (decl))
410 parms = TREE_CHAIN (parms);
413 push_inline_template_parms_recursive (parms, levels);
416 /* Remember how many levels of template parameters we pushed so that
417 we can pop them later. */
418 if (!inline_parm_levels)
419 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
420 if (inline_parm_levels_used == inline_parm_levels->num_elements)
421 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
422 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
423 ++inline_parm_levels_used;
426 /* Undo the effects of begin_member_template_processing. */
429 maybe_end_member_template_processing (void)
433 if (!inline_parm_levels_used)
436 --inline_parm_levels_used;
438 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
441 --processing_template_decl;
442 current_template_parms = TREE_CHAIN (current_template_parms);
447 /* Returns nonzero iff T is a member template function. We must be
450 template <class T> class C { void f(); }
452 Here, f is a template function, and a member, but not a member
453 template. This function does not concern itself with the origin of
454 T, only its present state. So if we have
456 template <class T> class C { template <class U> void f(U); }
458 then neither C<int>::f<char> nor C<T>::f<double> is considered
459 to be a member template. But, `template <class U> void
460 C<int>::f(U)' is considered a member template. */
463 is_member_template (tree t)
465 if (!DECL_FUNCTION_TEMPLATE_P (t))
466 /* Anything that isn't a function or a template function is
467 certainly not a member template. */
470 /* A local class can't have member templates. */
471 if (decl_function_context (t))
474 return (DECL_FUNCTION_MEMBER_P (DECL_TEMPLATE_RESULT (t))
475 /* If there are more levels of template parameters than
476 there are template classes surrounding the declaration,
477 then we have a member template. */
478 && (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
479 template_class_depth (DECL_CONTEXT (t))));
483 /* Returns nonzero iff T is a member template class. See
484 is_member_template for a description of what precisely constitutes
485 a member template. */
488 is_member_template_class (tree t)
490 if (!DECL_CLASS_TEMPLATE_P (t))
491 /* Anything that isn't a class template, is certainly not a member
495 if (!DECL_CLASS_SCOPE_P (t))
496 /* Anything whose context isn't a class type is surely not a
500 /* If there are more levels of template parameters than there are
501 template classes surrounding the declaration, then we have a
503 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
504 template_class_depth (DECL_CONTEXT (t)));
508 /* Return a new template argument vector which contains all of ARGS,
509 but has as its innermost set of arguments the EXTRA_ARGS. */
512 add_to_template_args (tree args, tree extra_args)
519 extra_depth = TMPL_ARGS_DEPTH (extra_args);
520 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
522 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
523 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
525 for (j = 1; j <= extra_depth; ++j, ++i)
526 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
531 /* Like add_to_template_args, but only the outermost ARGS are added to
532 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
533 (EXTRA_ARGS) levels are added. This function is used to combine
534 the template arguments from a partial instantiation with the
535 template arguments used to attain the full instantiation from the
536 partial instantiation. */
539 add_outermost_template_args (tree args, tree extra_args)
543 /* If there are more levels of EXTRA_ARGS than there are ARGS,
544 something very fishy is going on. */
545 my_friendly_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args),
548 /* If *all* the new arguments will be the EXTRA_ARGS, just return
550 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
553 /* For the moment, we make ARGS look like it contains fewer levels. */
554 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
556 new_args = add_to_template_args (args, extra_args);
558 /* Now, we restore ARGS to its full dimensions. */
559 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
564 /* Return the N levels of innermost template arguments from the ARGS. */
567 get_innermost_template_args (tree args, int n)
573 my_friendly_assert (n >= 0, 20000603);
575 /* If N is 1, just return the innermost set of template arguments. */
577 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
579 /* If we're not removing anything, just return the arguments we were
581 extra_levels = TMPL_ARGS_DEPTH (args) - n;
582 my_friendly_assert (extra_levels >= 0, 20000603);
583 if (extra_levels == 0)
586 /* Make a new set of arguments, not containing the outer arguments. */
587 new_args = make_tree_vec (n);
588 for (i = 1; i <= n; ++i)
589 SET_TMPL_ARGS_LEVEL (new_args, i,
590 TMPL_ARGS_LEVEL (args, i + extra_levels));
595 /* We've got a template header coming up; push to a new level for storing
599 begin_template_parm_list (void)
601 /* We use a non-tag-transparent scope here, which causes pushtag to
602 put tags in this scope, rather than in the enclosing class or
603 namespace scope. This is the right thing, since we want
604 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
605 global template class, push_template_decl handles putting the
606 TEMPLATE_DECL into top-level scope. For a nested template class,
609 template <class T> struct S1 {
610 template <class T> struct S2 {};
613 pushtag contains special code to call pushdecl_with_scope on the
614 TEMPLATE_DECL for S2. */
615 begin_scope (sk_template_parms, NULL);
616 ++processing_template_decl;
617 ++processing_template_parmlist;
618 note_template_header (0);
621 /* This routine is called when a specialization is declared. If it is
622 invalid to declare a specialization here, an error is reported. */
625 check_specialization_scope (void)
627 tree scope = current_scope ();
631 An explicit specialization shall be declared in the namespace of
632 which the template is a member, or, for member templates, in the
633 namespace of which the enclosing class or enclosing class
634 template is a member. An explicit specialization of a member
635 function, member class or static data member of a class template
636 shall be declared in the namespace of which the class template
638 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
639 error ("explicit specialization in non-namespace scope `%D'",
644 In an explicit specialization declaration for a member of a class
645 template or a member template that appears in namespace scope,
646 the member template and some of its enclosing class templates may
647 remain unspecialized, except that the declaration shall not
648 explicitly specialize a class member template if its enclosing
649 class templates are not explicitly specialized as well. */
650 if (current_template_parms)
651 error ("enclosing class templates are not explicitly specialized");
654 /* We've just seen template <>. */
657 begin_specialization (void)
659 begin_scope (sk_template_spec, NULL);
660 note_template_header (1);
661 check_specialization_scope ();
664 /* Called at then end of processing a declaration preceded by
668 end_specialization (void)
671 reset_specialization ();
674 /* Any template <>'s that we have seen thus far are not referring to a
675 function specialization. */
678 reset_specialization (void)
680 processing_specialization = 0;
681 template_header_count = 0;
684 /* We've just seen a template header. If SPECIALIZATION is nonzero,
685 it was of the form template <>. */
688 note_template_header (int specialization)
690 processing_specialization = specialization;
691 template_header_count++;
694 /* We're beginning an explicit instantiation. */
697 begin_explicit_instantiation (void)
699 my_friendly_assert (!processing_explicit_instantiation, 20020913);
700 processing_explicit_instantiation = true;
705 end_explicit_instantiation (void)
707 my_friendly_assert(processing_explicit_instantiation, 20020913);
708 processing_explicit_instantiation = false;
711 /* A explicit specialization or partial specialization TMPL is being
712 declared. Check that the namespace in which the specialization is
713 occurring is permissible. Returns false iff it is invalid to
714 specialize TMPL in the current namespace. */
717 check_specialization_namespace (tree tmpl)
719 tree tpl_ns = decl_namespace_context (tmpl);
723 An explicit specialization shall be declared in the namespace of
724 which the template is a member, or, for member templates, in the
725 namespace of which the enclosing class or enclosing class
726 template is a member. An explicit specialization of a member
727 function, member class or static data member of a class template
728 shall be declared in the namespace of which the class template is
730 if (is_associated_namespace (current_namespace, tpl_ns))
731 /* Same or super-using namespace. */
735 pedwarn ("specialization of `%D' in different namespace", tmpl);
736 cp_pedwarn_at (" from definition of `%#D'", tmpl);
741 /* The TYPE is being declared. If it is a template type, that means it
742 is a partial specialization. Do appropriate error-checking. */
745 maybe_process_partial_specialization (tree type)
747 /* TYPE maybe an ERROR_MARK_NODE. */
748 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
750 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
752 /* This is for ordinary explicit specialization and partial
753 specialization of a template class such as:
755 template <> class C<int>;
759 template <class T> class C<T*>;
761 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
763 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
764 && !COMPLETE_TYPE_P (type))
766 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
767 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
768 if (processing_template_decl)
769 push_template_decl (TYPE_MAIN_DECL (type));
771 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
772 error ("specialization of `%T' after instantiation", type);
774 else if (CLASS_TYPE_P (type)
775 && !CLASSTYPE_USE_TEMPLATE (type)
776 && CLASSTYPE_TEMPLATE_INFO (type)
777 && context && CLASS_TYPE_P (context)
778 && CLASSTYPE_TEMPLATE_INFO (context))
780 /* This is for an explicit specialization of member class
781 template according to [temp.expl.spec/18]:
783 template <> template <class U> class C<int>::D;
785 The context `C<int>' must be an implicit instantiation.
786 Otherwise this is just a member class template declared
789 template <> class C<int> { template <class U> class D; };
790 template <> template <class U> class C<int>::D;
792 In the first case, `C<int>::D' is a specialization of `C<T>::D'
793 while in the second case, `C<int>::D' is a primary template
794 and `C<T>::D' may not exist. */
796 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
797 && !COMPLETE_TYPE_P (type))
801 if (current_namespace
802 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
804 pedwarn ("specializing `%#T' in different namespace", type);
805 cp_pedwarn_at (" from definition of `%#D'",
806 CLASSTYPE_TI_TEMPLATE (type));
809 /* Check for invalid specialization after instantiation:
811 template <> template <> class C<int>::D<int>;
812 template <> template <class U> class C<int>::D; */
814 for (t = DECL_TEMPLATE_INSTANTIATIONS
815 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
816 t; t = TREE_CHAIN (t))
817 if (TREE_VALUE (t) != type
818 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
819 error ("specialization `%T' after instantiation `%T'",
820 type, TREE_VALUE (t));
822 /* Mark TYPE as a specialization. And as a result, we only
823 have one level of template argument for the innermost
825 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
826 CLASSTYPE_TI_ARGS (type)
827 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
830 else if (processing_specialization)
831 error ("explicit specialization of non-template `%T'", type);
834 /* Retrieve the specialization (in the sense of [temp.spec] - a
835 specialization is either an instantiation or an explicit
836 specialization) of TMPL for the given template ARGS. If there is
837 no such specialization, return NULL_TREE. The ARGS are a vector of
838 arguments, or a vector of vectors of arguments, in the case of
839 templates with more than one level of parameters. */
842 retrieve_specialization (tree tmpl, tree args)
846 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
848 /* There should be as many levels of arguments as there are
849 levels of parameters. */
850 my_friendly_assert (TMPL_ARGS_DEPTH (args)
851 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
854 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
857 if (comp_template_args (TREE_PURPOSE (s), args))
858 return TREE_VALUE (s);
863 /* Like retrieve_specialization, but for local declarations. */
866 retrieve_local_specialization (tree tmpl)
868 tree spec = htab_find_with_hash (local_specializations, tmpl,
869 htab_hash_pointer (tmpl));
870 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
873 /* Returns nonzero iff DECL is a specialization of TMPL. */
876 is_specialization_of (tree decl, tree tmpl)
880 if (TREE_CODE (decl) == FUNCTION_DECL)
884 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
890 my_friendly_assert (TREE_CODE (decl) == TYPE_DECL, 0);
892 for (t = TREE_TYPE (decl);
894 t = CLASSTYPE_USE_TEMPLATE (t)
895 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
896 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
903 /* Returns nonzero iff DECL is a specialization of friend declaration
904 FRIEND according to [temp.friend]. */
907 is_specialization_of_friend (tree decl, tree friend)
909 bool need_template = true;
912 my_friendly_assert (TREE_CODE (decl) == FUNCTION_DECL, 0);
914 /* For [temp.friend/6] when FRIEND is an ordinary member function
915 of a template class, we want to check if DECL is a specialization
917 if (TREE_CODE (friend) == FUNCTION_DECL
918 && DECL_TEMPLATE_INFO (friend)
919 && !DECL_USE_TEMPLATE (friend))
921 friend = DECL_TI_TEMPLATE (friend);
922 need_template = false;
925 /* There is nothing to do if this is not a template friend. */
926 if (TREE_CODE (friend) != TEMPLATE_DECL)
929 if (is_specialization_of (decl, friend))
933 A member of a class template may be declared to be a friend of a
934 non-template class. In this case, the corresponding member of
935 every specialization of the class template is a friend of the
936 class granting friendship.
938 For example, given a template friend declaration
940 template <class T> friend void A<T>::f();
942 the member function below is considered a friend
944 template <> struct A<int> {
948 For this type of template friend, TEMPLATE_DEPTH below will be
949 nonzero. To determine if DECL is a friend of FRIEND, we first
950 check if the enclosing class is a specialization of another. */
952 template_depth = template_class_depth (DECL_CONTEXT (friend));
954 && DECL_CLASS_SCOPE_P (decl)
955 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
956 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
958 /* Next, we check the members themselves. In order to handle
959 a few tricky cases like
961 template <class T> friend void A<T>::g(T t);
962 template <class T> template <T t> friend void A<T>::h();
964 we need to figure out what ARGS is (corresponding to `T' in above
965 examples) from DECL for later processing. */
967 tree context = DECL_CONTEXT (decl);
968 tree args = NULL_TREE;
969 int current_depth = 0;
970 while (current_depth < template_depth)
972 if (CLASSTYPE_TEMPLATE_INFO (context))
974 if (current_depth == 0)
975 args = TYPE_TI_ARGS (context);
977 args = add_to_template_args (TYPE_TI_ARGS (context), args);
980 context = TYPE_CONTEXT (context);
983 if (TREE_CODE (decl) == FUNCTION_DECL)
988 tree friend_args_type;
991 /* Make sure that both DECL and FRIEND are templates or
993 is_template = DECL_TEMPLATE_INFO (decl)
994 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
995 if (need_template ^ is_template)
997 else if (is_template)
999 /* If both are templates, check template parameter list. */
1001 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1003 if (!comp_template_parms
1004 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1008 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1011 decl_type = TREE_TYPE (decl);
1013 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1014 tf_none, NULL_TREE);
1015 if (friend_type == error_mark_node)
1018 /* Check if return types match. */
1019 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1022 /* Check if function parameter types match, ignoring the
1023 `this' parameter. */
1024 friend_args_type = TYPE_ARG_TYPES (friend_type);
1025 decl_args_type = TYPE_ARG_TYPES (decl_type);
1026 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1027 friend_args_type = TREE_CHAIN (friend_args_type);
1028 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1029 decl_args_type = TREE_CHAIN (decl_args_type);
1030 if (compparms (decl_args_type, friend_args_type))
1037 /* Register the specialization SPEC as a specialization of TMPL with
1038 the indicated ARGS. Returns SPEC, or an equivalent prior
1039 declaration, if available. */
1042 register_specialization (tree spec, tree tmpl, tree args)
1046 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
1048 if (TREE_CODE (spec) == FUNCTION_DECL
1049 && uses_template_parms (DECL_TI_ARGS (spec)))
1050 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1051 register it; we want the corresponding TEMPLATE_DECL instead.
1052 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1053 the more obvious `uses_template_parms (spec)' to avoid problems
1054 with default function arguments. In particular, given
1055 something like this:
1057 template <class T> void f(T t1, T t = T())
1059 the default argument expression is not substituted for in an
1060 instantiation unless and until it is actually needed. */
1063 /* There should be as many levels of arguments as there are
1064 levels of parameters. */
1065 my_friendly_assert (TMPL_ARGS_DEPTH (args)
1066 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
1069 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1073 tree fn = TREE_VALUE (s);
1075 /* We can sometimes try to re-register a specialization that we've
1076 already got. In particular, regenerate_decl_from_template
1077 calls duplicate_decls which will update the specialization
1078 list. But, we'll still get called again here anyhow. It's
1079 more convenient to simply allow this than to try to prevent it. */
1082 else if (comp_template_args (TREE_PURPOSE (s), args)
1083 && DECL_TEMPLATE_SPECIALIZATION (spec))
1085 if (DECL_TEMPLATE_INSTANTIATION (fn))
1088 || DECL_EXPLICIT_INSTANTIATION (fn))
1090 error ("specialization of %D after instantiation",
1096 /* This situation should occur only if the first
1097 specialization is an implicit instantiation, the
1098 second is an explicit specialization, and the
1099 implicit instantiation has not yet been used.
1100 That situation can occur if we have implicitly
1101 instantiated a member function and then
1102 specialized it later.
1104 We can also wind up here if a friend declaration
1105 that looked like an instantiation turns out to be
1108 template <class T> void foo(T);
1109 class S { friend void foo<>(int) };
1110 template <> void foo(int);
1112 We transform the existing DECL in place so that
1113 any pointers to it become pointers to the updated
1116 If there was a definition for the template, but
1117 not for the specialization, we want this to look
1118 as if there were no definition, and vice
1120 DECL_INITIAL (fn) = NULL_TREE;
1121 duplicate_decls (spec, fn);
1126 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1128 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
1129 /* Dup decl failed, but this is a new definition. Set
1130 the line number so any errors match this new
1132 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1139 /* A specialization must be declared in the same namespace as the
1140 template it is specializing. */
1141 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1142 && !check_specialization_namespace (tmpl))
1143 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1145 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1146 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1151 /* Unregister the specialization SPEC as a specialization of TMPL.
1152 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1153 if the SPEC was listed as a specialization of TMPL. */
1156 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1160 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1162 s = &TREE_CHAIN (*s))
1163 if (TREE_VALUE (*s) == spec)
1166 *s = TREE_CHAIN (*s);
1168 TREE_VALUE (*s) = new_spec;
1175 /* Compare an entry in the local specializations hash table P1 (which
1176 is really a pointer to a TREE_LIST) with P2 (which is really a
1180 eq_local_specializations (const void *p1, const void *p2)
1182 return TREE_VALUE ((tree) p1) == (tree) p2;
1185 /* Hash P1, an entry in the local specializations table. */
1188 hash_local_specialization (const void* p1)
1190 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1193 /* Like register_specialization, but for local declarations. We are
1194 registering SPEC, an instantiation of TMPL. */
1197 register_local_specialization (tree spec, tree tmpl)
1201 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1202 htab_hash_pointer (tmpl), INSERT);
1203 *slot = build_tree_list (spec, tmpl);
1206 /* Print the list of candidate FNS in an error message. */
1209 print_candidates (tree fns)
1213 const char *str = "candidates are:";
1215 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1219 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1220 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
1225 /* Returns the template (one of the functions given by TEMPLATE_ID)
1226 which can be specialized to match the indicated DECL with the
1227 explicit template args given in TEMPLATE_ID. The DECL may be
1228 NULL_TREE if none is available. In that case, the functions in
1229 TEMPLATE_ID are non-members.
1231 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1232 specialization of a member template.
1234 The TEMPLATE_COUNT is the number of references to qualifying
1235 template classes that appeared in the name of the function. See
1236 check_explicit_specialization for a more accurate description.
1238 The template args (those explicitly specified and those deduced)
1239 are output in a newly created vector *TARGS_OUT.
1241 If it is impossible to determine the result, an error message is
1242 issued. The error_mark_node is returned to indicate failure. */
1245 determine_specialization (tree template_id,
1248 int need_member_template,
1253 tree explicit_targs;
1254 tree candidates = NULL_TREE;
1255 tree templates = NULL_TREE;
1257 struct cp_binding_level *b;
1259 *targs_out = NULL_TREE;
1261 if (template_id == error_mark_node)
1262 return error_mark_node;
1264 fns = TREE_OPERAND (template_id, 0);
1265 explicit_targs = TREE_OPERAND (template_id, 1);
1267 if (fns == error_mark_node)
1268 return error_mark_node;
1270 /* Check for baselinks. */
1271 if (BASELINK_P (fns))
1272 fns = BASELINK_FUNCTIONS (fns);
1274 if (!is_overloaded_fn (fns))
1276 error ("`%D' is not a function template", fns);
1277 return error_mark_node;
1280 /* Count the number of template headers specified for this
1283 for (b = current_binding_level;
1284 b->kind == sk_template_parms || b->kind == sk_template_spec;
1288 for (; fns; fns = OVL_NEXT (fns))
1290 tree fn = OVL_CURRENT (fns);
1292 if (TREE_CODE (fn) == TEMPLATE_DECL)
1294 tree decl_arg_types;
1297 /* DECL might be a specialization of FN. */
1299 /* Adjust the type of DECL in case FN is a static member. */
1300 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1301 if (DECL_STATIC_FUNCTION_P (fn)
1302 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1303 decl_arg_types = TREE_CHAIN (decl_arg_types);
1305 /* Check that the number of function parameters matches.
1307 template <class T> void f(int i = 0);
1308 template <> void f<int>();
1309 The specialization f<int> is invalid but is not caught
1310 by get_bindings below. */
1312 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1313 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1316 /* For a non-static member function, we need to make sure that
1317 the const qualification is the same. This can be done by
1318 checking the 'this' in the argument list. */
1319 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1320 && !same_type_p (TREE_VALUE (fn_arg_types),
1321 TREE_VALUE (decl_arg_types)))
1324 /* In case of explicit specialization, we need to check if
1325 the number of template headers appearing in the specialization
1326 is correct. This is usually done in check_explicit_specialization,
1327 but the check done there cannot be exhaustive when specializing
1328 member functions. Consider the following code:
1330 template <> void A<int>::f(int);
1331 template <> template <> void A<int>::f(int);
1333 Assuming that A<int> is not itself an explicit specialization
1334 already, the first line specializes "f" which is a non-template
1335 member function, whilst the second line specializes "f" which
1336 is a template member function. So both lines are syntactically
1337 correct, and check_explicit_specialization does not reject
1340 Here, we can do better, as we are matching the specialization
1341 against the declarations. We count the number of template
1342 headers, and we check if they match TEMPLATE_COUNT + 1
1343 (TEMPLATE_COUNT is the number of qualifying template classes,
1344 plus there must be another header for the member template
1347 Notice that if header_count is zero, this is not a
1348 specialization but rather a template instantiation, so there
1349 is no check we can perform here. */
1350 if (header_count && header_count != template_count + 1)
1353 /* See whether this function might be a specialization of this
1355 targs = get_bindings (fn, decl, explicit_targs);
1358 /* We cannot deduce template arguments that when used to
1359 specialize TMPL will produce DECL. */
1362 /* Save this template, and the arguments deduced. */
1363 templates = tree_cons (targs, fn, templates);
1365 else if (need_member_template)
1366 /* FN is an ordinary member function, and we need a
1367 specialization of a member template. */
1369 else if (TREE_CODE (fn) != FUNCTION_DECL)
1370 /* We can get IDENTIFIER_NODEs here in certain erroneous
1373 else if (!DECL_FUNCTION_MEMBER_P (fn))
1374 /* This is just an ordinary non-member function. Nothing can
1375 be a specialization of that. */
1377 else if (DECL_ARTIFICIAL (fn))
1378 /* Cannot specialize functions that are created implicitly. */
1382 tree decl_arg_types;
1384 /* This is an ordinary member function. However, since
1385 we're here, we can assume it's enclosing class is a
1386 template class. For example,
1388 template <typename T> struct S { void f(); };
1389 template <> void S<int>::f() {}
1391 Here, S<int>::f is a non-template, but S<int> is a
1392 template class. If FN has the same type as DECL, we
1393 might be in business. */
1395 if (!DECL_TEMPLATE_INFO (fn))
1396 /* Its enclosing class is an explicit specialization
1397 of a template class. This is not a candidate. */
1400 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1401 TREE_TYPE (TREE_TYPE (fn))))
1402 /* The return types differ. */
1405 /* Adjust the type of DECL in case FN is a static member. */
1406 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1407 if (DECL_STATIC_FUNCTION_P (fn)
1408 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1409 decl_arg_types = TREE_CHAIN (decl_arg_types);
1411 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1414 candidates = tree_cons (NULL_TREE, fn, candidates);
1418 if (templates && TREE_CHAIN (templates))
1424 It is possible for a specialization with a given function
1425 signature to be instantiated from more than one function
1426 template. In such cases, explicit specification of the
1427 template arguments must be used to uniquely identify the
1428 function template specialization being specialized.
1430 Note that here, there's no suggestion that we're supposed to
1431 determine which of the candidate templates is most
1432 specialized. However, we, also have:
1436 Partial ordering of overloaded function template
1437 declarations is used in the following contexts to select
1438 the function template to which a function template
1439 specialization refers:
1441 -- when an explicit specialization refers to a function
1444 So, we do use the partial ordering rules, at least for now.
1445 This extension can only serve to make invalid programs valid,
1446 so it's safe. And, there is strong anecdotal evidence that
1447 the committee intended the partial ordering rules to apply;
1448 the EDG front-end has that behavior, and John Spicer claims
1449 that the committee simply forgot to delete the wording in
1450 [temp.expl.spec]. */
1451 tree tmpl = most_specialized (templates, decl, explicit_targs);
1452 if (tmpl && tmpl != error_mark_node)
1454 targs = get_bindings (tmpl, decl, explicit_targs);
1455 templates = tree_cons (targs, tmpl, NULL_TREE);
1459 if (templates == NULL_TREE && candidates == NULL_TREE)
1461 cp_error_at ("template-id `%D' for `%+D' does not match any template declaration",
1463 return error_mark_node;
1465 else if ((templates && TREE_CHAIN (templates))
1466 || (candidates && TREE_CHAIN (candidates))
1467 || (templates && candidates))
1469 cp_error_at ("ambiguous template specialization `%D' for `%+D'",
1471 chainon (candidates, templates);
1472 print_candidates (candidates);
1473 return error_mark_node;
1476 /* We have one, and exactly one, match. */
1479 /* It was a specialization of an ordinary member function in a
1481 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1482 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1485 /* It was a specialization of a template. */
1486 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1487 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1489 *targs_out = copy_node (targs);
1490 SET_TMPL_ARGS_LEVEL (*targs_out,
1491 TMPL_ARGS_DEPTH (*targs_out),
1492 TREE_PURPOSE (templates));
1495 *targs_out = TREE_PURPOSE (templates);
1496 return TREE_VALUE (templates);
1499 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1500 but with the default argument values filled in from those in the
1504 copy_default_args_to_explicit_spec_1 (tree spec_types,
1507 tree new_spec_types;
1512 if (spec_types == void_list_node)
1513 return void_list_node;
1515 /* Substitute into the rest of the list. */
1517 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1518 TREE_CHAIN (tmpl_types));
1520 /* Add the default argument for this parameter. */
1521 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1522 TREE_VALUE (spec_types),
1526 /* DECL is an explicit specialization. Replicate default arguments
1527 from the template it specializes. (That way, code like:
1529 template <class T> void f(T = 3);
1530 template <> void f(double);
1533 works, as required.) An alternative approach would be to look up
1534 the correct default arguments at the call-site, but this approach
1535 is consistent with how implicit instantiations are handled. */
1538 copy_default_args_to_explicit_spec (tree decl)
1543 tree new_spec_types;
1547 tree object_type = NULL_TREE;
1548 tree in_charge = NULL_TREE;
1549 tree vtt = NULL_TREE;
1551 /* See if there's anything we need to do. */
1552 tmpl = DECL_TI_TEMPLATE (decl);
1553 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1554 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1555 if (TREE_PURPOSE (t))
1560 old_type = TREE_TYPE (decl);
1561 spec_types = TYPE_ARG_TYPES (old_type);
1563 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1565 /* Remove the this pointer, but remember the object's type for
1567 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1568 spec_types = TREE_CHAIN (spec_types);
1569 tmpl_types = TREE_CHAIN (tmpl_types);
1571 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1573 /* DECL may contain more parameters than TMPL due to the extra
1574 in-charge parameter in constructors and destructors. */
1575 in_charge = spec_types;
1576 spec_types = TREE_CHAIN (spec_types);
1578 if (DECL_HAS_VTT_PARM_P (decl))
1581 spec_types = TREE_CHAIN (spec_types);
1585 /* Compute the merged default arguments. */
1587 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1589 /* Compute the new FUNCTION_TYPE. */
1593 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1598 /* Put the in-charge parameter back. */
1599 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1600 TREE_VALUE (in_charge),
1603 new_type = build_method_type_directly (object_type,
1604 TREE_TYPE (old_type),
1608 new_type = build_function_type (TREE_TYPE (old_type),
1610 new_type = cp_build_type_attribute_variant (new_type,
1611 TYPE_ATTRIBUTES (old_type));
1612 new_type = build_exception_variant (new_type,
1613 TYPE_RAISES_EXCEPTIONS (old_type));
1614 TREE_TYPE (decl) = new_type;
1617 /* Check to see if the function just declared, as indicated in
1618 DECLARATOR, and in DECL, is a specialization of a function
1619 template. We may also discover that the declaration is an explicit
1620 instantiation at this point.
1622 Returns DECL, or an equivalent declaration that should be used
1623 instead if all goes well. Issues an error message if something is
1624 amiss. Returns error_mark_node if the error is not easily
1627 FLAGS is a bitmask consisting of the following flags:
1629 2: The function has a definition.
1630 4: The function is a friend.
1632 The TEMPLATE_COUNT is the number of references to qualifying
1633 template classes that appeared in the name of the function. For
1636 template <class T> struct S { void f(); };
1639 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1640 classes are not counted in the TEMPLATE_COUNT, so that in
1642 template <class T> struct S {};
1643 template <> struct S<int> { void f(); }
1644 template <> void S<int>::f();
1646 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1647 invalid; there should be no template <>.)
1649 If the function is a specialization, it is marked as such via
1650 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1651 is set up correctly, and it is added to the list of specializations
1652 for that template. */
1655 check_explicit_specialization (tree declarator,
1660 int have_def = flags & 2;
1661 int is_friend = flags & 4;
1662 int specialization = 0;
1663 int explicit_instantiation = 0;
1664 int member_specialization = 0;
1665 tree ctype = DECL_CLASS_CONTEXT (decl);
1666 tree dname = DECL_NAME (decl);
1669 tsk = current_tmpl_spec_kind (template_count);
1674 if (processing_specialization)
1677 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1679 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1682 /* This could be something like:
1684 template <class T> void f(T);
1685 class S { friend void f<>(int); } */
1689 /* This case handles bogus declarations like template <>
1690 template <class T> void f<int>(); */
1692 error ("template-id `%D' in declaration of primary template",
1699 case tsk_invalid_member_spec:
1700 /* The error has already been reported in
1701 check_specialization_scope. */
1702 return error_mark_node;
1704 case tsk_invalid_expl_inst:
1705 error ("template parameter list used in explicit instantiation");
1711 error ("definition provided for explicit instantiation");
1713 explicit_instantiation = 1;
1716 case tsk_excessive_parms:
1717 case tsk_insufficient_parms:
1718 if (tsk == tsk_excessive_parms)
1719 error ("too many template parameter lists in declaration of `%D'",
1721 else if (template_header_count)
1722 error("too few template parameter lists in declaration of `%D'",
1725 error("explicit specialization of `%D' must be introduced by "
1726 "`template <>'", decl);
1730 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1732 member_specialization = 1;
1738 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1740 /* This case handles bogus declarations like template <>
1741 template <class T> void f<int>(); */
1743 if (uses_template_parms (declarator))
1744 error ("function template partial specialization `%D' "
1745 "is not allowed", declarator);
1747 error ("template-id `%D' in declaration of primary template",
1752 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1753 /* This is a specialization of a member template, without
1754 specialization the containing class. Something like:
1756 template <class T> struct S {
1757 template <class U> void f (U);
1759 template <> template <class U> void S<int>::f(U) {}
1761 That's a specialization -- but of the entire template. */
1769 if (specialization || member_specialization)
1771 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1772 for (; t; t = TREE_CHAIN (t))
1773 if (TREE_PURPOSE (t))
1776 ("default argument specified in explicit specialization");
1779 if (current_lang_name == lang_name_c)
1780 error ("template specialization with C linkage");
1783 if (specialization || member_specialization || explicit_instantiation)
1785 tree tmpl = NULL_TREE;
1786 tree targs = NULL_TREE;
1788 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1789 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1793 my_friendly_assert (TREE_CODE (declarator) == IDENTIFIER_NODE, 0);
1798 /* If there is no class context, the explicit instantiation
1799 must be at namespace scope. */
1800 my_friendly_assert (DECL_NAMESPACE_SCOPE_P (decl), 20030625);
1802 /* Find the namespace binding, using the declaration
1804 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1807 declarator = lookup_template_function (fns, NULL_TREE);
1810 if (declarator == error_mark_node)
1811 return error_mark_node;
1813 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1815 if (!explicit_instantiation)
1816 /* A specialization in class scope. This is invalid,
1817 but the error will already have been flagged by
1818 check_specialization_scope. */
1819 return error_mark_node;
1822 /* It's not valid to write an explicit instantiation in
1825 class C { template void f(); }
1827 This case is caught by the parser. However, on
1830 template class C { void f(); };
1832 (which is invalid) we can get here. The error will be
1839 else if (ctype != NULL_TREE
1840 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1843 /* Find the list of functions in ctype that have the same
1844 name as the declared function. */
1845 tree name = TREE_OPERAND (declarator, 0);
1846 tree fns = NULL_TREE;
1849 if (constructor_name_p (name, ctype))
1851 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1853 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1854 : !TYPE_HAS_DESTRUCTOR (ctype))
1856 /* From [temp.expl.spec]:
1858 If such an explicit specialization for the member
1859 of a class template names an implicitly-declared
1860 special member function (clause _special_), the
1861 program is ill-formed.
1863 Similar language is found in [temp.explicit]. */
1864 error ("specialization of implicitly-declared special member function");
1865 return error_mark_node;
1868 name = is_constructor ? ctor_identifier : dtor_identifier;
1871 if (!DECL_CONV_FN_P (decl))
1873 idx = lookup_fnfields_1 (ctype, name);
1875 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1882 /* For a type-conversion operator, we cannot do a
1883 name-based lookup. We might be looking for `operator
1884 int' which will be a specialization of `operator T'.
1885 So, we find *all* the conversion operators, and then
1886 select from them. */
1889 methods = CLASSTYPE_METHOD_VEC (ctype);
1891 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1892 VEC_iterate (tree, methods, idx, ovl);
1895 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1896 /* There are no more conversion functions. */
1899 /* Glue all these conversion functions together
1900 with those we already have. */
1901 for (; ovl; ovl = OVL_NEXT (ovl))
1902 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1906 if (fns == NULL_TREE)
1908 error ("no member function `%D' declared in `%T'",
1910 return error_mark_node;
1913 TREE_OPERAND (declarator, 0) = fns;
1916 /* Figure out what exactly is being specialized at this point.
1917 Note that for an explicit instantiation, even one for a
1918 member function, we cannot tell apriori whether the
1919 instantiation is for a member template, or just a member
1920 function of a template class. Even if a member template is
1921 being instantiated, the member template arguments may be
1922 elided if they can be deduced from the rest of the
1924 tmpl = determine_specialization (declarator, decl,
1926 member_specialization,
1929 if (!tmpl || tmpl == error_mark_node)
1930 /* We couldn't figure out what this declaration was
1932 return error_mark_node;
1935 tree gen_tmpl = most_general_template (tmpl);
1937 if (explicit_instantiation)
1939 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
1940 is done by do_decl_instantiation later. */
1942 int arg_depth = TMPL_ARGS_DEPTH (targs);
1943 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
1945 if (arg_depth > parm_depth)
1947 /* If TMPL is not the most general template (for
1948 example, if TMPL is a friend template that is
1949 injected into namespace scope), then there will
1950 be too many levels of TARGS. Remove some of them
1955 new_targs = make_tree_vec (parm_depth);
1956 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
1957 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
1958 = TREE_VEC_ELT (targs, i);
1962 return instantiate_template (tmpl, targs, tf_error);
1965 /* If we thought that the DECL was a member function, but it
1966 turns out to be specializing a static member function,
1967 make DECL a static member function as well. */
1968 if (DECL_STATIC_FUNCTION_P (tmpl)
1969 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1970 revert_static_member_fn (decl);
1972 /* If this is a specialization of a member template of a
1973 template class. In we want to return the TEMPLATE_DECL,
1974 not the specialization of it. */
1975 if (tsk == tsk_template)
1977 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
1978 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
1981 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
1982 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
1983 = DECL_SOURCE_LOCATION (decl);
1988 /* Set up the DECL_TEMPLATE_INFO for DECL. */
1989 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
1991 /* Inherit default function arguments from the template
1992 DECL is specializing. */
1993 copy_default_args_to_explicit_spec (decl);
1995 /* This specialization has the same protection as the
1996 template it specializes. */
1997 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
1998 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2000 if (is_friend && !have_def)
2001 /* This is not really a declaration of a specialization.
2002 It's just the name of an instantiation. But, it's not
2003 a request for an instantiation, either. */
2004 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2005 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2006 /* This is indeed a specialization. In case of constructors
2007 and destructors, we need in-charge and not-in-charge
2008 versions in V3 ABI. */
2009 clone_function_decl (decl, /*update_method_vec_p=*/0);
2011 /* Register this specialization so that we can find it
2013 decl = register_specialization (decl, gen_tmpl, targs);
2020 /* TYPE is being declared. Verify that the use of template headers
2021 and such is reasonable. Issue error messages if not. */
2024 maybe_check_template_type (tree type)
2026 if (template_header_count)
2028 /* We are in the scope of some `template <...>' header. */
2031 = template_class_depth_real (TYPE_CONTEXT (type),
2032 /*count_specializations=*/1);
2034 if (template_header_count <= context_depth)
2035 /* This is OK; the template headers are for the context. We
2036 are actually too lenient here; like
2037 check_explicit_specialization we should consider the number
2038 of template types included in the actual declaration. For
2041 template <class T> struct S {
2042 template <class U> template <class V>
2048 template <class T> struct S {
2049 template <class U> struct I;
2052 template <class T> template <class U.
2057 else if (template_header_count > context_depth + 1)
2058 /* There are two many template parameter lists. */
2059 error ("too many template parameter lists in declaration of `%T'", type);
2063 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2064 parameters. These are represented in the same format used for
2065 DECL_TEMPLATE_PARMS. */
2067 int comp_template_parms (tree parms1, tree parms2)
2072 if (parms1 == parms2)
2075 for (p1 = parms1, p2 = parms2;
2076 p1 != NULL_TREE && p2 != NULL_TREE;
2077 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2079 tree t1 = TREE_VALUE (p1);
2080 tree t2 = TREE_VALUE (p2);
2083 my_friendly_assert (TREE_CODE (t1) == TREE_VEC, 0);
2084 my_friendly_assert (TREE_CODE (t2) == TREE_VEC, 0);
2086 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2089 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2091 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2092 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2094 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2097 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2099 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2104 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2105 /* One set of parameters has more parameters lists than the
2112 /* Complain if DECL shadows a template parameter.
2114 [temp.local]: A template-parameter shall not be redeclared within its
2115 scope (including nested scopes). */
2118 check_template_shadow (tree decl)
2122 /* If we're not in a template, we can't possibly shadow a template
2124 if (!current_template_parms)
2127 /* Figure out what we're shadowing. */
2128 if (TREE_CODE (decl) == OVERLOAD)
2129 decl = OVL_CURRENT (decl);
2130 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2132 /* If there's no previous binding for this name, we're not shadowing
2133 anything, let alone a template parameter. */
2137 /* If we're not shadowing a template parameter, we're done. Note
2138 that OLDDECL might be an OVERLOAD (or perhaps even an
2139 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2141 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2144 /* We check for decl != olddecl to avoid bogus errors for using a
2145 name inside a class. We check TPFI to avoid duplicate errors for
2146 inline member templates. */
2148 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2151 cp_error_at ("declaration of `%#D'", decl);
2152 cp_error_at (" shadows template parm `%#D'", olddecl);
2155 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2156 ORIG_LEVEL, DECL, and TYPE. */
2159 build_template_parm_index (int index,
2165 tree t = make_node (TEMPLATE_PARM_INDEX);
2166 TEMPLATE_PARM_IDX (t) = index;
2167 TEMPLATE_PARM_LEVEL (t) = level;
2168 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2169 TEMPLATE_PARM_DECL (t) = decl;
2170 TREE_TYPE (t) = type;
2171 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2172 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2173 TREE_READONLY (t) = TREE_READONLY (decl);
2178 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2179 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2180 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2181 new one is created. */
2184 reduce_template_parm_level (tree index, tree type, int levels)
2186 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2187 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2188 != TEMPLATE_PARM_LEVEL (index) - levels))
2190 tree orig_decl = TEMPLATE_PARM_DECL (index);
2193 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2194 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2195 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2196 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2197 DECL_ARTIFICIAL (decl) = 1;
2198 SET_DECL_TEMPLATE_PARM_P (decl);
2200 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2201 TEMPLATE_PARM_LEVEL (index) - levels,
2202 TEMPLATE_PARM_ORIG_LEVEL (index),
2204 TEMPLATE_PARM_DESCENDANTS (index) = t;
2206 /* Template template parameters need this. */
2207 DECL_TEMPLATE_PARMS (decl)
2208 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2211 return TEMPLATE_PARM_DESCENDANTS (index);
2214 /* Process information from new template parameter NEXT and append it to the
2215 LIST being built. This new parameter is a non-type parameter iff
2216 IS_NON_TYPE is true. */
2219 process_template_parm (tree list, tree next, bool is_non_type)
2227 my_friendly_assert (TREE_CODE (parm) == TREE_LIST, 259);
2228 defval = TREE_PURPOSE (parm);
2232 tree p = TREE_VALUE (tree_last (list));
2234 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2235 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2237 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2245 parm = TREE_VALUE (parm);
2247 SET_DECL_TEMPLATE_PARM_P (parm);
2251 The top-level cv-qualifiers on the template-parameter are
2252 ignored when determining its type. */
2253 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2255 /* A template parameter is not modifiable. */
2256 TREE_CONSTANT (parm) = 1;
2257 TREE_INVARIANT (parm) = 1;
2258 TREE_READONLY (parm) = 1;
2259 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2260 TREE_TYPE (parm) = void_type_node;
2261 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2262 TREE_CONSTANT (decl) = 1;
2263 TREE_INVARIANT (decl) = 1;
2264 TREE_READONLY (decl) = 1;
2265 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2266 = build_template_parm_index (idx, processing_template_decl,
2267 processing_template_decl,
2268 decl, TREE_TYPE (parm));
2273 parm = TREE_VALUE (TREE_VALUE (parm));
2275 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2277 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2278 /* This is for distinguishing between real templates and template
2279 template parameters */
2280 TREE_TYPE (parm) = t;
2281 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2286 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2287 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2288 decl = build_decl (TYPE_DECL, parm, t);
2291 TYPE_NAME (t) = decl;
2292 TYPE_STUB_DECL (t) = decl;
2294 TEMPLATE_TYPE_PARM_INDEX (t)
2295 = build_template_parm_index (idx, processing_template_decl,
2296 processing_template_decl,
2297 decl, TREE_TYPE (parm));
2299 DECL_ARTIFICIAL (decl) = 1;
2300 SET_DECL_TEMPLATE_PARM_P (decl);
2302 parm = build_tree_list (defval, parm);
2303 return chainon (list, parm);
2306 /* The end of a template parameter list has been reached. Process the
2307 tree list into a parameter vector, converting each parameter into a more
2308 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2312 end_template_parm_list (tree parms)
2316 tree saved_parmlist = make_tree_vec (list_length (parms));
2318 current_template_parms
2319 = tree_cons (size_int (processing_template_decl),
2320 saved_parmlist, current_template_parms);
2322 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2324 next = TREE_CHAIN (parm);
2325 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2326 TREE_CHAIN (parm) = NULL_TREE;
2329 --processing_template_parmlist;
2331 return saved_parmlist;
2334 /* end_template_decl is called after a template declaration is seen. */
2337 end_template_decl (void)
2339 reset_specialization ();
2341 if (! processing_template_decl)
2344 /* This matches the pushlevel in begin_template_parm_list. */
2347 --processing_template_decl;
2348 current_template_parms = TREE_CHAIN (current_template_parms);
2351 /* Given a template argument vector containing the template PARMS.
2352 The innermost PARMS are given first. */
2355 current_template_args (void)
2358 tree args = NULL_TREE;
2359 int length = TMPL_PARMS_DEPTH (current_template_parms);
2362 /* If there is only one level of template parameters, we do not
2363 create a TREE_VEC of TREE_VECs. Instead, we return a single
2364 TREE_VEC containing the arguments. */
2366 args = make_tree_vec (length);
2368 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2370 tree a = copy_node (TREE_VALUE (header));
2373 TREE_TYPE (a) = NULL_TREE;
2374 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2376 tree t = TREE_VEC_ELT (a, i);
2378 /* T will be a list if we are called from within a
2379 begin/end_template_parm_list pair, but a vector directly
2380 if within a begin/end_member_template_processing pair. */
2381 if (TREE_CODE (t) == TREE_LIST)
2385 if (TREE_CODE (t) == TYPE_DECL
2386 || TREE_CODE (t) == TEMPLATE_DECL)
2389 t = DECL_INITIAL (t);
2390 TREE_VEC_ELT (a, i) = t;
2395 TREE_VEC_ELT (args, --l) = a;
2403 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2404 template PARMS. Used by push_template_decl below. */
2407 build_template_decl (tree decl, tree parms)
2409 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2410 DECL_TEMPLATE_PARMS (tmpl) = parms;
2411 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2412 if (DECL_LANG_SPECIFIC (decl))
2414 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2415 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2416 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2417 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2418 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2419 if (DECL_OVERLOADED_OPERATOR_P (decl))
2420 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2421 DECL_OVERLOADED_OPERATOR_P (decl));
2427 struct template_parm_data
2429 /* The level of the template parameters we are currently
2433 /* The index of the specialization argument we are currently
2437 /* An array whose size is the number of template parameters. The
2438 elements are nonzero if the parameter has been used in any one
2439 of the arguments processed so far. */
2442 /* An array whose size is the number of template arguments. The
2443 elements are nonzero if the argument makes use of template
2444 parameters of this level. */
2445 int* arg_uses_template_parms;
2448 /* Subroutine of push_template_decl used to see if each template
2449 parameter in a partial specialization is used in the explicit
2450 argument list. If T is of the LEVEL given in DATA (which is
2451 treated as a template_parm_data*), then DATA->PARMS is marked
2455 mark_template_parm (tree t, void* data)
2459 struct template_parm_data* tpd = (struct template_parm_data*) data;
2461 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2463 level = TEMPLATE_PARM_LEVEL (t);
2464 idx = TEMPLATE_PARM_IDX (t);
2468 level = TEMPLATE_TYPE_LEVEL (t);
2469 idx = TEMPLATE_TYPE_IDX (t);
2472 if (level == tpd->level)
2474 tpd->parms[idx] = 1;
2475 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2478 /* Return zero so that for_each_template_parm will continue the
2479 traversal of the tree; we want to mark *every* template parm. */
2483 /* Process the partial specialization DECL. */
2486 process_partial_specialization (tree decl)
2488 tree type = TREE_TYPE (decl);
2489 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2490 tree specargs = CLASSTYPE_TI_ARGS (type);
2491 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2492 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2493 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2494 int nargs = TREE_VEC_LENGTH (inner_args);
2495 int ntparms = TREE_VEC_LENGTH (inner_parms);
2497 int did_error_intro = 0;
2498 struct template_parm_data tpd;
2499 struct template_parm_data tpd2;
2501 /* We check that each of the template parameters given in the
2502 partial specialization is used in the argument list to the
2503 specialization. For example:
2505 template <class T> struct S;
2506 template <class T> struct S<T*>;
2508 The second declaration is OK because `T*' uses the template
2509 parameter T, whereas
2511 template <class T> struct S<int>;
2513 is no good. Even trickier is:
2524 The S2<T> declaration is actually invalid; it is a
2525 full-specialization. Of course,
2528 struct S2<T (*)(U)>;
2530 or some such would have been OK. */
2531 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2532 tpd.parms = alloca (sizeof (int) * ntparms);
2533 memset (tpd.parms, 0, sizeof (int) * ntparms);
2535 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2536 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2537 for (i = 0; i < nargs; ++i)
2539 tpd.current_arg = i;
2540 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2541 &mark_template_parm,
2545 for (i = 0; i < ntparms; ++i)
2546 if (tpd.parms[i] == 0)
2548 /* One of the template parms was not used in the
2550 if (!did_error_intro)
2552 error ("template parameters not used in partial specialization:");
2553 did_error_intro = 1;
2557 TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2560 /* [temp.class.spec]
2562 The argument list of the specialization shall not be identical to
2563 the implicit argument list of the primary template. */
2564 if (comp_template_args
2566 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2568 error ("partial specialization `%T' does not specialize any template arguments", type);
2570 /* [temp.class.spec]
2572 A partially specialized non-type argument expression shall not
2573 involve template parameters of the partial specialization except
2574 when the argument expression is a simple identifier.
2576 The type of a template parameter corresponding to a specialized
2577 non-type argument shall not be dependent on a parameter of the
2579 my_friendly_assert (nargs == DECL_NTPARMS (maintmpl), 0);
2581 for (i = 0; i < nargs; ++i)
2583 tree arg = TREE_VEC_ELT (inner_args, i);
2584 if (/* These first two lines are the `non-type' bit. */
2586 && TREE_CODE (arg) != TEMPLATE_DECL
2587 /* This next line is the `argument expression is not just a
2588 simple identifier' condition and also the `specialized
2589 non-type argument' bit. */
2590 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2592 if (tpd.arg_uses_template_parms[i])
2593 error ("template argument `%E' involves template parameter(s)", arg);
2596 /* Look at the corresponding template parameter,
2597 marking which template parameters its type depends
2600 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2605 /* We haven't yet initialized TPD2. Do so now. */
2606 tpd2.arg_uses_template_parms
2607 = alloca (sizeof (int) * nargs);
2608 /* The number of parameters here is the number in the
2609 main template, which, as checked in the assertion
2611 tpd2.parms = alloca (sizeof (int) * nargs);
2613 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2616 /* Mark the template parameters. But this time, we're
2617 looking for the template parameters of the main
2618 template, not in the specialization. */
2619 tpd2.current_arg = i;
2620 tpd2.arg_uses_template_parms[i] = 0;
2621 memset (tpd2.parms, 0, sizeof (int) * nargs);
2622 for_each_template_parm (type,
2623 &mark_template_parm,
2627 if (tpd2.arg_uses_template_parms [i])
2629 /* The type depended on some template parameters.
2630 If they are fully specialized in the
2631 specialization, that's OK. */
2633 for (j = 0; j < nargs; ++j)
2634 if (tpd2.parms[j] != 0
2635 && tpd.arg_uses_template_parms [j])
2637 error ("type `%T' of template argument `%E' depends on template parameter(s)",
2647 if (retrieve_specialization (maintmpl, specargs))
2648 /* We've already got this specialization. */
2651 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2652 = tree_cons (inner_args, inner_parms,
2653 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2654 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2658 /* Check that a template declaration's use of default arguments is not
2659 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2660 nonzero if DECL is the thing declared by a primary template.
2661 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2664 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2667 int last_level_to_check;
2672 A default template-argument shall not be specified in a
2673 function template declaration or a function template definition, nor
2674 in the template-parameter-list of the definition of a member of a
2677 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2678 /* You can't have a function template declaration in a local
2679 scope, nor you can you define a member of a class template in a
2683 if (current_class_type
2684 && !TYPE_BEING_DEFINED (current_class_type)
2685 && DECL_LANG_SPECIFIC (decl)
2686 /* If this is either a friend defined in the scope of the class
2687 or a member function. */
2688 && (DECL_FUNCTION_MEMBER_P (decl)
2689 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2690 : DECL_FRIEND_CONTEXT (decl)
2691 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2693 /* And, if it was a member function, it really was defined in
2694 the scope of the class. */
2695 && (!DECL_FUNCTION_MEMBER_P (decl)
2696 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2697 /* We already checked these parameters when the template was
2698 declared, so there's no need to do it again now. This function
2699 was defined in class scope, but we're processing it's body now
2700 that the class is complete. */
2705 If a template-parameter has a default template-argument, all
2706 subsequent template-parameters shall have a default
2707 template-argument supplied. */
2708 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2710 tree inner_parms = TREE_VALUE (parm_level);
2711 int ntparms = TREE_VEC_LENGTH (inner_parms);
2712 int seen_def_arg_p = 0;
2715 for (i = 0; i < ntparms; ++i)
2717 tree parm = TREE_VEC_ELT (inner_parms, i);
2718 if (TREE_PURPOSE (parm))
2720 else if (seen_def_arg_p)
2722 error ("no default argument for `%D'", TREE_VALUE (parm));
2723 /* For better subsequent error-recovery, we indicate that
2724 there should have been a default argument. */
2725 TREE_PURPOSE (parm) = error_mark_node;
2730 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2731 /* For an ordinary class template, default template arguments are
2732 allowed at the innermost level, e.g.:
2733 template <class T = int>
2735 but, in a partial specialization, they're not allowed even
2736 there, as we have in [temp.class.spec]:
2738 The template parameter list of a specialization shall not
2739 contain default template argument values.
2741 So, for a partial specialization, or for a function template,
2742 we look at all of them. */
2745 /* But, for a primary class template that is not a partial
2746 specialization we look at all template parameters except the
2748 parms = TREE_CHAIN (parms);
2750 /* Figure out what error message to issue. */
2751 if (TREE_CODE (decl) == FUNCTION_DECL)
2752 msg = "default template arguments may not be used in function templates";
2753 else if (is_partial)
2754 msg = "default template arguments may not be used in partial specializations";
2756 msg = "default argument for template parameter for class enclosing `%D'";
2758 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2759 /* If we're inside a class definition, there's no need to
2760 examine the parameters to the class itself. On the one
2761 hand, they will be checked when the class is defined, and,
2762 on the other, default arguments are valid in things like:
2763 template <class T = double>
2764 struct S { template <class U> void f(U); };
2765 Here the default argument for `S' has no bearing on the
2766 declaration of `f'. */
2767 last_level_to_check = template_class_depth (current_class_type) + 1;
2769 /* Check everything. */
2770 last_level_to_check = 0;
2772 for (parm_level = parms;
2773 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2774 parm_level = TREE_CHAIN (parm_level))
2776 tree inner_parms = TREE_VALUE (parm_level);
2780 ntparms = TREE_VEC_LENGTH (inner_parms);
2781 for (i = 0; i < ntparms; ++i)
2782 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2790 /* Clear out the default argument so that we are not
2792 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2795 /* At this point, if we're still interested in issuing messages,
2796 they must apply to classes surrounding the object declared. */
2798 msg = "default argument for template parameter for class enclosing `%D'";
2802 /* Worker for push_template_decl_real, called via
2803 for_each_template_parm. DATA is really an int, indicating the
2804 level of the parameters we are interested in. If T is a template
2805 parameter of that level, return nonzero. */
2808 template_parm_this_level_p (tree t, void* data)
2810 int this_level = *(int *)data;
2813 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2814 level = TEMPLATE_PARM_LEVEL (t);
2816 level = TEMPLATE_TYPE_LEVEL (t);
2817 return level == this_level;
2820 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2821 parameters given by current_template_args, or reuses a
2822 previously existing one, if appropriate. Returns the DECL, or an
2823 equivalent one, if it is replaced via a call to duplicate_decls.
2825 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2828 push_template_decl_real (tree decl, int is_friend)
2836 int new_template_p = 0;
2838 if (decl == error_mark_node)
2841 /* See if this is a partial specialization. */
2842 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2843 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2844 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2846 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2849 /* For a friend, we want the context of the friend function, not
2850 the type of which it is a friend. */
2851 ctx = DECL_CONTEXT (decl);
2852 else if (CP_DECL_CONTEXT (decl)
2853 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2854 /* In the case of a virtual function, we want the class in which
2856 ctx = CP_DECL_CONTEXT (decl);
2858 /* Otherwise, if we're currently defining some class, the DECL
2859 is assumed to be a member of the class. */
2860 ctx = current_scope ();
2862 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2865 if (!DECL_CONTEXT (decl))
2866 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2868 /* See if this is a primary template. */
2869 primary = template_parm_scope_p ();
2873 if (current_lang_name == lang_name_c)
2874 error ("template with C linkage");
2875 else if (TREE_CODE (decl) == TYPE_DECL
2876 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2877 error ("template class without a name");
2878 else if (TREE_CODE (decl) == FUNCTION_DECL
2879 && DECL_DESTRUCTOR_P (decl))
2883 A destructor shall not be a member template. */
2884 error ("destructor `%D' declared as member template", decl);
2885 return error_mark_node;
2887 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2888 && CLASS_TYPE_P (TREE_TYPE (decl)))
2889 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx))
2890 || TREE_CODE (decl) == FUNCTION_DECL)
2894 error ("template declaration of `%#D'", decl);
2895 return error_mark_node;
2899 /* Check to see that the rules regarding the use of default
2900 arguments are not being violated. */
2901 check_default_tmpl_args (decl, current_template_parms,
2902 primary, is_partial);
2905 return process_partial_specialization (decl);
2907 args = current_template_args ();
2910 || TREE_CODE (ctx) == FUNCTION_DECL
2911 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
2912 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
2914 if (DECL_LANG_SPECIFIC (decl)
2915 && DECL_TEMPLATE_INFO (decl)
2916 && DECL_TI_TEMPLATE (decl))
2917 tmpl = DECL_TI_TEMPLATE (decl);
2918 /* If DECL is a TYPE_DECL for a class-template, then there won't
2919 be DECL_LANG_SPECIFIC. The information equivalent to
2920 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2921 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
2922 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2923 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2925 /* Since a template declaration already existed for this
2926 class-type, we must be redeclaring it here. Make sure
2927 that the redeclaration is valid. */
2928 redeclare_class_template (TREE_TYPE (decl),
2929 current_template_parms);
2930 /* We don't need to create a new TEMPLATE_DECL; just use the
2931 one we already had. */
2932 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2936 tmpl = build_template_decl (decl, current_template_parms);
2939 if (DECL_LANG_SPECIFIC (decl)
2940 && DECL_TEMPLATE_SPECIALIZATION (decl))
2942 /* A specialization of a member template of a template
2944 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2945 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
2946 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
2952 tree a, t, current, parms;
2955 if (TREE_CODE (decl) == TYPE_DECL)
2957 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
2958 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
2959 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2960 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2961 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2964 error ("`%D' does not declare a template type", decl);
2968 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
2970 error ("template definition of non-template `%#D'", decl);
2974 tmpl = DECL_TI_TEMPLATE (decl);
2976 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
2977 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
2978 && DECL_TEMPLATE_SPECIALIZATION (decl)
2979 && is_member_template (tmpl))
2983 /* The declaration is a specialization of a member
2984 template, declared outside the class. Therefore, the
2985 innermost template arguments will be NULL, so we
2986 replace them with the arguments determined by the
2987 earlier call to check_explicit_specialization. */
2988 args = DECL_TI_ARGS (decl);
2991 = build_template_decl (decl, current_template_parms);
2992 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
2993 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
2994 DECL_TI_TEMPLATE (decl) = new_tmpl;
2995 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
2996 DECL_TEMPLATE_INFO (new_tmpl)
2997 = tree_cons (tmpl, args, NULL_TREE);
2999 register_specialization (new_tmpl,
3000 most_general_template (tmpl),
3005 /* Make sure the template headers we got make sense. */
3007 parms = DECL_TEMPLATE_PARMS (tmpl);
3008 i = TMPL_PARMS_DEPTH (parms);
3009 if (TMPL_ARGS_DEPTH (args) != i)
3011 error ("expected %d levels of template parms for `%#D', got %d",
3012 i, decl, TMPL_ARGS_DEPTH (args));
3015 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3017 a = TMPL_ARGS_LEVEL (args, i);
3018 t = INNERMOST_TEMPLATE_PARMS (parms);
3020 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3022 if (current == decl)
3023 error ("got %d template parameters for `%#D'",
3024 TREE_VEC_LENGTH (a), decl);
3026 error ("got %d template parameters for `%#T'",
3027 TREE_VEC_LENGTH (a), current);
3028 error (" but %d required", TREE_VEC_LENGTH (t));
3031 /* Perhaps we should also check that the parms are used in the
3032 appropriate qualifying scopes in the declarator? */
3034 if (current == decl)
3037 current = TYPE_CONTEXT (current);
3041 DECL_TEMPLATE_RESULT (tmpl) = decl;
3042 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3044 /* Push template declarations for global functions and types. Note
3045 that we do not try to push a global template friend declared in a
3046 template class; such a thing may well depend on the template
3047 parameters of the class. */
3048 if (new_template_p && !ctx
3049 && !(is_friend && template_class_depth (current_class_type) > 0))
3050 tmpl = pushdecl_namespace_level (tmpl);
3054 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3055 if (DECL_CONV_FN_P (tmpl))
3057 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3059 /* It is a conversion operator. See if the type converted to
3060 depends on innermost template operands. */
3062 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3064 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3068 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3069 back to its most general template. If TMPL is a specialization,
3070 ARGS may only have the innermost set of arguments. Add the missing
3071 argument levels if necessary. */
3072 if (DECL_TEMPLATE_INFO (tmpl))
3073 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3075 info = tree_cons (tmpl, args, NULL_TREE);
3077 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3079 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3080 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3081 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3082 /* Don't change the name if we've already set it up. */
3083 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3084 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3086 else if (DECL_LANG_SPECIFIC (decl))
3087 DECL_TEMPLATE_INFO (decl) = info;
3089 return DECL_TEMPLATE_RESULT (tmpl);
3093 push_template_decl (tree decl)
3095 return push_template_decl_real (decl, 0);
3098 /* Called when a class template TYPE is redeclared with the indicated
3099 template PARMS, e.g.:
3101 template <class T> struct S;
3102 template <class T> struct S {}; */
3105 redeclare_class_template (tree type, tree parms)
3111 if (!TYPE_TEMPLATE_INFO (type))
3113 error ("`%T' is not a template type", type);
3117 tmpl = TYPE_TI_TEMPLATE (type);
3118 if (!PRIMARY_TEMPLATE_P (tmpl))
3119 /* The type is nested in some template class. Nothing to worry
3120 about here; there are no new template parameters for the nested
3124 parms = INNERMOST_TEMPLATE_PARMS (parms);
3125 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3127 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3129 cp_error_at ("previous declaration `%D'", tmpl);
3130 error ("used %d template parameter%s instead of %d",
3131 TREE_VEC_LENGTH (tmpl_parms),
3132 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
3133 TREE_VEC_LENGTH (parms));
3137 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3139 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3140 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3141 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3142 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3144 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm))
3146 cp_error_at ("template parameter `%#D'", tmpl_parm);
3147 error ("redeclared here as `%#D'", parm);
3151 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3153 /* We have in [temp.param]:
3155 A template-parameter may not be given default arguments
3156 by two different declarations in the same scope. */
3157 error ("redefinition of default argument for `%#D'", parm);
3158 error ("%J original definition appeared here", tmpl_parm);
3162 if (parm_default != NULL_TREE)
3163 /* Update the previous template parameters (which are the ones
3164 that will really count) with the new default value. */
3165 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3166 else if (tmpl_default != NULL_TREE)
3167 /* Update the new parameters, too; they'll be used as the
3168 parameters for any members. */
3169 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3173 /* Simplify EXPR if it is a non-dependent expression. Returns the
3174 (possibly simplified) expression. */
3177 fold_non_dependent_expr (tree expr)
3179 /* If we're in a template, but EXPR isn't value dependent, simplify
3180 it. We're supposed to treat:
3182 template <typename T> void f(T[1 + 1]);
3183 template <typename T> void f(T[2]);
3185 as two declarations of the same function, for example. */
3186 if (processing_template_decl
3187 && !type_dependent_expression_p (expr)
3188 && !value_dependent_expression_p (expr))
3190 HOST_WIDE_INT saved_processing_template_decl;
3192 saved_processing_template_decl = processing_template_decl;
3193 processing_template_decl = 0;
3194 expr = tsubst_copy_and_build (expr,
3197 /*in_decl=*/NULL_TREE,
3198 /*function_p=*/false);
3199 processing_template_decl = saved_processing_template_decl;
3204 /* Attempt to convert the non-type template parameter EXPR to the
3205 indicated TYPE. If the conversion is successful, return the
3206 converted value. If the conversion is unsuccessful, return
3207 NULL_TREE if we issued an error message, or error_mark_node if we
3208 did not. We issue error messages for out-and-out bad template
3209 parameters, but not simply because the conversion failed, since we
3210 might be just trying to do argument deduction. Both TYPE and EXPR
3211 must be non-dependent. */
3214 convert_nontype_argument (tree type, tree expr)
3218 /* If we are in a template, EXPR may be non-dependent, but still
3219 have a syntactic, rather than semantic, form. For example, EXPR
3220 might be a SCOPE_REF, rather than the VAR_DECL to which the
3221 SCOPE_REF refers. Preserving the qualifying scope is necessary
3222 so that access checking can be performed when the template is
3223 instantiated -- but here we need the resolved form so that we can
3224 convert the argument. */
3225 expr = fold_non_dependent_expr (expr);
3226 expr_type = TREE_TYPE (expr);
3228 /* A template-argument for a non-type, non-template
3229 template-parameter shall be one of:
3231 --an integral constant-expression of integral or enumeration
3234 --the name of a non-type template-parameter; or
3236 --the name of an object or function with external linkage,
3237 including function templates and function template-ids but
3238 excluding non-static class members, expressed as id-expression;
3241 --the address of an object or function with external linkage,
3242 including function templates and function template-ids but
3243 excluding non-static class members, expressed as & id-expression
3244 where the & is optional if the name refers to a function or
3247 --a pointer to member expressed as described in _expr.unary.op_. */
3249 /* An integral constant-expression can include const variables or
3250 . enumerators. Simplify things by folding them to their values,
3251 unless we're about to bind the declaration to a reference
3253 if (INTEGRAL_TYPE_P (expr_type) && TREE_CODE (type) != REFERENCE_TYPE)
3256 tree const_expr = decl_constant_value (expr);
3257 /* In a template, the initializer for a VAR_DECL may not be
3258 marked as TREE_CONSTANT, in which case decl_constant_value
3259 will not return the initializer. Handle that special case
3261 if (expr == const_expr
3262 && DECL_INTEGRAL_CONSTANT_VAR_P (expr)
3263 /* DECL_INITIAL can be NULL if we are processing a
3264 variable initialized to an expression involving itself.
3265 We know it is initialized to a constant -- but not what
3267 && DECL_INITIAL (expr))
3268 const_expr = DECL_INITIAL (expr);
3269 if (expr == const_expr)
3271 expr = fold_non_dependent_expr (const_expr);
3274 if (is_overloaded_fn (expr))
3275 /* OK for now. We'll check that it has external linkage later.
3276 Check this first since if expr_type is the unknown_type_node
3277 we would otherwise complain below. */
3279 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3281 if (TREE_CODE (expr) != PTRMEM_CST)
3284 else if (TYPE_PTR_P (expr_type)
3285 || TREE_CODE (expr_type) == ARRAY_TYPE
3286 || TREE_CODE (type) == REFERENCE_TYPE
3287 /* If expr is the address of an overloaded function, we
3288 will get the unknown_type_node at this point. */
3289 || expr_type == unknown_type_node)
3295 if (TREE_CODE (expr_type) == ARRAY_TYPE
3296 || (TREE_CODE (type) == REFERENCE_TYPE
3297 && TREE_CODE (e) != ADDR_EXPR))
3301 if (TREE_CODE (e) != ADDR_EXPR)
3304 error ("`%E' is not a valid template argument", expr);
3305 if (TYPE_PTR_P (expr_type))
3307 if (TREE_CODE (TREE_TYPE (expr_type)) == FUNCTION_TYPE)
3308 error ("it must be the address of a function with external linkage");
3310 error ("it must be the address of an object with external linkage");
3312 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3313 error ("it must be a pointer-to-member of the form `&X::Y'");
3318 referent = TREE_OPERAND (e, 0);
3319 STRIP_NOPS (referent);
3322 if (TREE_CODE (referent) == STRING_CST)
3324 error ("string literal %E is not a valid template argument because it is the address of an object with static linkage",
3329 if (TREE_CODE (referent) == SCOPE_REF)
3330 referent = TREE_OPERAND (referent, 1);
3332 if (is_overloaded_fn (referent))
3333 /* We'll check that it has external linkage later. */
3335 else if (TREE_CODE (referent) != VAR_DECL)
3337 else if (!DECL_EXTERNAL_LINKAGE_P (referent))
3339 error ("address of non-extern `%E' cannot be used as template argument", referent);
3340 return error_mark_node;
3343 else if (INTEGRAL_TYPE_P (expr_type) || TYPE_PTR_TO_MEMBER_P (expr_type))
3345 if (! TREE_CONSTANT (expr))
3348 error ("non-constant `%E' cannot be used as template argument",
3356 error ("type '%T' cannot be used as a value for a non-type "
3357 "template-parameter", expr);
3358 else if (DECL_P (expr))
3359 error ("invalid use of '%D' as a non-type template-argument", expr);
3361 error ("invalid use of '%E' as a non-type template-argument", expr);
3366 switch (TREE_CODE (type))
3371 /* For a non-type template-parameter of integral or enumeration
3372 type, integral promotions (_conv.prom_) and integral
3373 conversions (_conv.integral_) are applied. */
3374 if (!INTEGRAL_TYPE_P (expr_type))
3375 return error_mark_node;
3377 /* [conv.integral] does not allow conversions between two different
3378 enumeration types. */
3379 if (TREE_CODE (type) == ENUMERAL_TYPE
3380 && TREE_CODE (expr_type) == ENUMERAL_TYPE
3381 && !same_type_ignoring_top_level_qualifiers_p (type, expr_type))
3382 return error_mark_node;
3384 /* It's safe to call digest_init in this case; we know we're
3385 just converting one integral constant expression to another. */
3386 expr = digest_init (type, expr, (tree*) 0);
3388 if (TREE_CODE (expr) != INTEGER_CST)
3389 /* Curiously, some TREE_CONSTANT integral expressions do not
3390 simplify to integer constants. For example, `3 % 0',
3391 remains a TRUNC_MOD_EXPR. */
3400 /* For a non-type template-parameter of type pointer to data
3401 member, qualification conversions (_conv.qual_) are
3403 e = perform_qualification_conversions (type, expr);
3404 if (TREE_CODE (e) == NOP_EXPR)
3405 /* The call to perform_qualification_conversions will
3406 insert a NOP_EXPR over EXPR to do express conversion,
3407 if necessary. But, that will confuse us if we use
3408 this (converted) template parameter to instantiate
3409 another template; then the thing will not look like a
3410 valid template argument. So, just make a new
3411 constant, of the appropriate type. */
3412 e = make_ptrmem_cst (type, PTRMEM_CST_MEMBER (expr));
3418 tree type_pointed_to = TREE_TYPE (type);
3420 if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE)
3422 /* For a non-type template-parameter of type pointer to
3423 function, only the function-to-pointer conversion
3424 (_conv.func_) is applied. If the template-argument
3425 represents a set of overloaded functions (or a pointer to
3426 such), the matching function is selected from the set
3431 if (TREE_CODE (expr) == ADDR_EXPR)
3432 fns = TREE_OPERAND (expr, 0);
3436 fn = instantiate_type (type_pointed_to, fns, tf_none);
3438 if (fn == error_mark_node)
3439 return error_mark_node;
3441 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3443 if (really_overloaded_fn (fns))
3444 return error_mark_node;
3449 expr = build_unary_op (ADDR_EXPR, fn, 0);
3451 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3457 /* For a non-type template-parameter of type pointer to
3458 object, qualification conversions (_conv.qual_) and the
3459 array-to-pointer conversion (_conv.array_) are applied.
3460 [Note: In particular, neither the null pointer conversion
3461 (_conv.ptr_) nor the derived-to-base conversion
3462 (_conv.ptr_) are applied. Although 0 is a valid
3463 template-argument for a non-type template-parameter of
3464 integral type, it is not a valid template-argument for a
3465 non-type template-parameter of pointer type.]
3467 The call to decay_conversion performs the
3468 array-to-pointer conversion, if appropriate. */
3469 expr = decay_conversion (expr);
3471 if (expr == error_mark_node)
3472 return error_mark_node;
3474 return perform_qualification_conversions (type, expr);
3479 case REFERENCE_TYPE:
3481 tree type_referred_to = TREE_TYPE (type);
3483 /* If this expression already has reference type, get the
3484 underlying object. */
3485 if (TREE_CODE (expr_type) == REFERENCE_TYPE)
3487 if (TREE_CODE (expr) == NOP_EXPR
3488 && TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR)
3490 my_friendly_assert (TREE_CODE (expr) == ADDR_EXPR, 20000604);
3491 expr = TREE_OPERAND (expr, 0);
3492 expr_type = TREE_TYPE (expr);
3495 if (TREE_CODE (type_referred_to) == FUNCTION_TYPE)
3497 /* For a non-type template-parameter of type reference to
3498 function, no conversions apply. If the
3499 template-argument represents a set of overloaded
3500 functions, the matching function is selected from the
3501 set (_over.over_). */
3504 fn = instantiate_type (type_referred_to, expr, tf_none);
3506 if (fn == error_mark_node)
3507 return error_mark_node;
3509 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3511 if (really_overloaded_fn (expr))
3512 /* Don't issue an error here; we might get a different
3513 function if the overloading had worked out
3515 return error_mark_node;
3520 my_friendly_assert (same_type_p (type_referred_to,
3528 /* For a non-type template-parameter of type reference to
3529 object, no conversions apply. The type referred to by the
3530 reference may be more cv-qualified than the (otherwise
3531 identical) type of the template-argument. The
3532 template-parameter is bound directly to the
3533 template-argument, which must be an lvalue. */
3534 if (!same_type_p (TYPE_MAIN_VARIANT (expr_type),
3535 TYPE_MAIN_VARIANT (type_referred_to))
3536 || !at_least_as_qualified_p (type_referred_to,
3538 || !real_lvalue_p (expr))
3539 return error_mark_node;
3542 cxx_mark_addressable (expr);
3543 return build_nop (type, build_address (expr));
3549 my_friendly_assert (TYPE_PTRMEMFUNC_P (type), 20010112);
3551 /* For a non-type template-parameter of type pointer to member
3552 function, no conversions apply. If the template-argument
3553 represents a set of overloaded member functions, the
3554 matching member function is selected from the set
3557 if (!TYPE_PTRMEMFUNC_P (expr_type) &&
3558 expr_type != unknown_type_node)
3559 return error_mark_node;
3561 if (TREE_CODE (expr) == PTRMEM_CST)
3563 /* A ptr-to-member constant. */
3564 if (!same_type_p (type, expr_type))
3565 return error_mark_node;
3570 if (TREE_CODE (expr) != ADDR_EXPR)
3571 return error_mark_node;
3573 expr = instantiate_type (type, expr, tf_none);
3575 if (expr == error_mark_node)
3576 return error_mark_node;
3578 if (!same_type_p (type, TREE_TYPE (expr)))
3579 return error_mark_node;
3586 /* All non-type parameters must have one of these types. */
3591 return error_mark_node;
3594 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3595 template template parameters. Both PARM_PARMS and ARG_PARMS are
3596 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3599 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3600 the case, then extra parameters must have default arguments.
3602 Consider the example:
3603 template <class T, class Allocator = allocator> class vector;
3604 template<template <class U> class TT> class C;
3606 C<vector> is a valid instantiation. PARM_PARMS for the above code
3607 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3608 T and Allocator) and OUTER_ARGS contains the argument that is used to
3609 substitute the TT parameter. */
3612 coerce_template_template_parms (tree parm_parms,
3614 tsubst_flags_t complain,
3618 int nparms, nargs, i;
3621 my_friendly_assert (TREE_CODE (parm_parms) == TREE_VEC, 0);
3622 my_friendly_assert (TREE_CODE (arg_parms) == TREE_VEC, 0);
3624 nparms = TREE_VEC_LENGTH (parm_parms);
3625 nargs = TREE_VEC_LENGTH (arg_parms);
3627 /* The rule here is opposite of coerce_template_parms. */
3630 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3633 for (i = 0; i < nparms; ++i)
3635 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3636 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3638 if (arg == NULL_TREE || arg == error_mark_node
3639 || parm == NULL_TREE || parm == error_mark_node)
3642 if (TREE_CODE (arg) != TREE_CODE (parm))
3645 switch (TREE_CODE (parm))
3651 /* We encounter instantiations of templates like
3652 template <template <template <class> class> class TT>
3655 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3656 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3658 if (!coerce_template_template_parms
3659 (parmparm, argparm, complain, in_decl, outer_args))
3665 /* The tsubst call is used to handle cases such as
3667 template <int> class C {};
3668 template <class T, template <T> class TT> class D {};
3671 i.e. the parameter list of TT depends on earlier parameters. */
3672 if (!dependent_type_p (TREE_TYPE (arg))
3674 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3686 /* Convert the indicated template ARG as necessary to match the
3687 indicated template PARM. Returns the converted ARG, or
3688 error_mark_node if the conversion was unsuccessful. Error and
3689 warning messages are issued under control of COMPLAIN. This
3690 conversion is for the Ith parameter in the parameter list. ARGS is
3691 the full set of template arguments deduced so far. */
3694 convert_template_argument (tree parm,
3697 tsubst_flags_t complain,
3703 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3705 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3707 if (TREE_CODE (arg) == TREE_LIST
3708 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3710 /* The template argument was the name of some
3711 member function. That's usually
3712 invalid, but static members are OK. In any
3713 case, grab the underlying fields/functions
3714 and issue an error later if required. */
3715 arg = TREE_VALUE (arg);
3716 TREE_TYPE (arg) = unknown_type_node;
3719 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3720 requires_type = (TREE_CODE (parm) == TYPE_DECL
3721 || requires_tmpl_type);
3723 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3724 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3725 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3726 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3729 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3730 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3731 arg = TYPE_STUB_DECL (arg);
3733 is_type = TYPE_P (arg) || is_tmpl_type;
3735 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3736 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3738 pedwarn ("to refer to a type member of a template parameter, use `typename %E'", arg);
3740 arg = make_typename_type (TREE_OPERAND (arg, 0),
3741 TREE_OPERAND (arg, 1),
3742 complain & tf_error);
3745 if (is_type != requires_type)
3749 if (complain & tf_error)
3751 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3754 error (" expected a constant of type `%T', got `%T'",
3756 (is_tmpl_type ? DECL_NAME (arg) : arg));
3757 else if (requires_tmpl_type)
3758 error (" expected a class template, got `%E'", arg);
3760 error (" expected a type, got `%E'", arg);
3763 return error_mark_node;
3765 if (is_tmpl_type ^ requires_tmpl_type)
3767 if (in_decl && (complain & tf_error))
3769 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3772 error (" expected a type, got `%T'", DECL_NAME (arg));
3774 error (" expected a class template, got `%T'", arg);
3776 return error_mark_node;
3781 if (requires_tmpl_type)
3783 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3784 /* The number of argument required is not known yet.
3785 Just accept it for now. */
3786 val = TREE_TYPE (arg);
3789 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3790 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3792 if (coerce_template_template_parms (parmparm, argparm,
3798 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3800 if (val != error_mark_node
3801 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3802 val = TREE_TYPE (val);
3806 if (in_decl && (complain & tf_error))
3808 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3810 error (" expected a template of type `%D', got `%D'", parm, arg);
3813 val = error_mark_node;
3822 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3824 if (invalid_nontype_parm_type_p (t, complain))
3825 return error_mark_node;
3827 if (!uses_template_parms (arg) && !uses_template_parms (t))
3828 /* We used to call digest_init here. However, digest_init
3829 will report errors, which we don't want when complain
3830 is zero. More importantly, digest_init will try too
3831 hard to convert things: for example, `0' should not be
3832 converted to pointer type at this point according to
3833 the standard. Accepting this is not merely an
3834 extension, since deciding whether or not these
3835 conversions can occur is part of determining which
3836 function template to call, or whether a given explicit
3837 argument specification is valid. */
3838 val = convert_nontype_argument (t, arg);
3842 if (val == NULL_TREE)
3843 val = error_mark_node;
3844 else if (val == error_mark_node && (complain & tf_error))
3845 error ("could not convert template argument `%E' to `%T'",
3852 /* Convert all template arguments to their appropriate types, and
3853 return a vector containing the innermost resulting template
3854 arguments. If any error occurs, return error_mark_node. Error and
3855 warning messages are issued under control of COMPLAIN.
3857 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3858 provided in ARGLIST, or else trailing parameters must have default
3859 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3860 deduction for any unspecified trailing arguments. */
3863 coerce_template_parms (tree parms,
3866 tsubst_flags_t complain,
3867 int require_all_arguments)
3869 int nparms, nargs, i, lost = 0;
3872 tree new_inner_args;
3874 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3875 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3876 nparms = TREE_VEC_LENGTH (parms);
3880 && require_all_arguments
3881 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3883 if (complain & tf_error)
3885 error ("wrong number of template arguments (%d, should be %d)",
3889 cp_error_at ("provided for `%D'", in_decl);
3892 return error_mark_node;
3895 new_inner_args = make_tree_vec (nparms);
3896 new_args = add_outermost_template_args (args, new_inner_args);
3897 for (i = 0; i < nparms; i++)
3902 /* Get the Ith template parameter. */
3903 parm = TREE_VEC_ELT (parms, i);
3905 /* Calculate the Ith argument. */
3907 arg = TREE_VEC_ELT (inner_args, i);
3908 else if (require_all_arguments)
3909 /* There must be a default arg in this case. */
3910 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
3915 my_friendly_assert (arg, 20030727);
3916 if (arg == error_mark_node)
3917 error ("template argument %d is invalid", i + 1);
3919 arg = convert_template_argument (TREE_VALUE (parm),
3920 arg, new_args, complain, i,
3923 if (arg == error_mark_node)
3925 TREE_VEC_ELT (new_inner_args, i) = arg;
3929 return error_mark_node;
3931 return new_inner_args;
3934 /* Returns 1 if template args OT and NT are equivalent. */
3937 template_args_equal (tree ot, tree nt)
3942 if (TREE_CODE (nt) == TREE_VEC)
3943 /* For member templates */
3944 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
3945 else if (TYPE_P (nt))
3946 return TYPE_P (ot) && same_type_p (ot, nt);
3947 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
3950 return cp_tree_equal (ot, nt);
3953 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
3954 of template arguments. Returns 0 otherwise. */
3957 comp_template_args (tree oldargs, tree newargs)
3961 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
3964 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
3966 tree nt = TREE_VEC_ELT (newargs, i);
3967 tree ot = TREE_VEC_ELT (oldargs, i);
3969 if (! template_args_equal (ot, nt))
3975 /* Given class template name and parameter list, produce a user-friendly name
3976 for the instantiation. */
3979 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
3981 static struct obstack scratch_obstack;
3982 static char *scratch_firstobj;
3985 if (!scratch_firstobj)
3986 gcc_obstack_init (&scratch_obstack);
3988 obstack_free (&scratch_obstack, scratch_firstobj);
3989 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
3991 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
3992 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
3996 nparms = TREE_VEC_LENGTH (parms);
3997 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
3998 my_friendly_assert (nparms == TREE_VEC_LENGTH (arglist), 268);
3999 for (i = 0; i < nparms; i++)
4001 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4002 tree arg = TREE_VEC_ELT (arglist, i);
4007 if (TREE_CODE (parm) == TYPE_DECL)
4009 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4012 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4014 if (TREE_CODE (arg) == TEMPLATE_DECL)
4016 /* Already substituted with real template. Just output
4017 the template name here */
4018 tree context = DECL_CONTEXT (arg);
4021 /* The template may be defined in a namespace, or
4022 may be a member template. */
4023 my_friendly_assert (TREE_CODE (context) == NAMESPACE_DECL
4024 || CLASS_TYPE_P (context),
4026 cat(decl_as_string (DECL_CONTEXT (arg), TFF_PLAIN_IDENTIFIER));
4029 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4032 /* Output the parameter declaration. */
4033 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4037 my_friendly_assert (TREE_CODE (parm) == PARM_DECL, 269);
4039 /* No need to check arglist against parmlist here; we did that
4040 in coerce_template_parms, called from lookup_template_class. */
4041 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4044 char *bufp = obstack_next_free (&scratch_obstack);
4046 while (bufp[offset - 1] == ' ')
4048 obstack_blank_fast (&scratch_obstack, offset);
4050 /* B<C<char> >, not B<C<char>> */
4051 if (bufp[offset - 1] == '>')
4056 return (char *) obstack_base (&scratch_obstack);
4060 classtype_mangled_name (tree t)
4062 if (CLASSTYPE_TEMPLATE_INFO (t)
4063 /* Specializations have already had their names set up in
4064 lookup_template_class. */
4065 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4067 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4069 /* For non-primary templates, the template parameters are
4070 implicit from their surrounding context. */
4071 if (PRIMARY_TEMPLATE_P (tmpl))
4073 tree name = DECL_NAME (tmpl);
4074 char *mangled_name = mangle_class_name_for_template
4075 (IDENTIFIER_POINTER (name),
4076 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4077 CLASSTYPE_TI_ARGS (t));
4078 tree id = get_identifier (mangled_name);
4079 IDENTIFIER_TEMPLATE (id) = name;
4084 return TYPE_IDENTIFIER (t);
4088 add_pending_template (tree d)
4090 tree ti = (TYPE_P (d)
4091 ? CLASSTYPE_TEMPLATE_INFO (d)
4092 : DECL_TEMPLATE_INFO (d));
4096 if (TI_PENDING_TEMPLATE_FLAG (ti))
4099 /* We are called both from instantiate_decl, where we've already had a
4100 tinst_level pushed, and instantiate_template, where we haven't.
4102 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4105 push_tinst_level (d);
4107 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4108 if (last_pending_template)
4109 TREE_CHAIN (last_pending_template) = pt;
4111 pending_templates = pt;
4113 last_pending_template = pt;
4115 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4122 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4123 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4124 documentation for TEMPLATE_ID_EXPR. */
4127 lookup_template_function (tree fns, tree arglist)
4131 if (fns == error_mark_node || arglist == error_mark_node)
4132 return error_mark_node;
4134 my_friendly_assert (!arglist || TREE_CODE (arglist) == TREE_VEC, 20030726);
4135 if (fns == NULL_TREE
4136 || TREE_CODE (fns) == FUNCTION_DECL)
4138 error ("non-template used as template");
4139 return error_mark_node;
4142 my_friendly_assert (TREE_CODE (fns) == TEMPLATE_DECL
4143 || TREE_CODE (fns) == OVERLOAD
4145 || TREE_CODE (fns) == IDENTIFIER_NODE,
4148 if (BASELINK_P (fns))
4150 BASELINK_FUNCTIONS (fns) = build (TEMPLATE_ID_EXPR,
4152 BASELINK_FUNCTIONS (fns),
4157 type = TREE_TYPE (fns);
4158 if (TREE_CODE (fns) == OVERLOAD || !type)
4159 type = unknown_type_node;
4161 return build (TEMPLATE_ID_EXPR, type, fns, arglist);
4164 /* Within the scope of a template class S<T>, the name S gets bound
4165 (in build_self_reference) to a TYPE_DECL for the class, not a
4166 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4167 or one of its enclosing classes, and that type is a template,
4168 return the associated TEMPLATE_DECL. Otherwise, the original
4169 DECL is returned. */
4172 maybe_get_template_decl_from_type_decl (tree decl)
4174 return (decl != NULL_TREE
4175 && TREE_CODE (decl) == TYPE_DECL
4176 && DECL_ARTIFICIAL (decl)
4177 && CLASS_TYPE_P (TREE_TYPE (decl))
4178 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4179 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4182 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4183 parameters, find the desired type.
4185 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4187 IN_DECL, if non-NULL, is the template declaration we are trying to
4190 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4191 the class we are looking up.
4193 Issue error and warning messages under control of COMPLAIN.
4195 If the template class is really a local class in a template
4196 function, then the FUNCTION_CONTEXT is the function in which it is
4197 being instantiated. */
4200 lookup_template_class (tree d1,
4205 tsubst_flags_t complain)
4207 tree template = NULL_TREE, parmlist;
4210 timevar_push (TV_NAME_LOOKUP);
4212 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4214 tree value = innermost_non_namespace_value (d1);
4215 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4220 push_decl_namespace (context);
4221 template = lookup_name (d1, /*prefer_type=*/0);
4222 template = maybe_get_template_decl_from_type_decl (template);
4224 pop_decl_namespace ();
4227 context = DECL_CONTEXT (template);
4229 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4231 tree type = TREE_TYPE (d1);
4233 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4234 an implicit typename for the second A. Deal with it. */
4235 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4236 type = TREE_TYPE (type);
4238 if (CLASSTYPE_TEMPLATE_INFO (type))
4240 template = CLASSTYPE_TI_TEMPLATE (type);
4241 d1 = DECL_NAME (template);
4244 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4245 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4247 template = TYPE_TI_TEMPLATE (d1);
4248 d1 = DECL_NAME (template);
4250 else if (TREE_CODE (d1) == TEMPLATE_DECL
4251 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4254 d1 = DECL_NAME (template);
4255 context = DECL_CONTEXT (template);
4258 /* Issue an error message if we didn't find a template. */
4261 if (complain & tf_error)
4262 error ("`%T' is not a template", d1);
4263 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4266 if (TREE_CODE (template) != TEMPLATE_DECL
4267 /* Make sure it's a user visible template, if it was named by
4269 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4270 && !PRIMARY_TEMPLATE_P (template)))
4272 if (complain & tf_error)
4274 error ("non-template type `%T' used as a template", d1);
4276 cp_error_at ("for template declaration `%D'", in_decl);
4278 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4281 complain &= ~tf_user;
4283 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4285 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4286 template arguments */
4291 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4293 /* Consider an example where a template template parameter declared as
4295 template <class T, class U = std::allocator<T> > class TT
4297 The template parameter level of T and U are one level larger than
4298 of TT. To proper process the default argument of U, say when an
4299 instantiation `TT<int>' is seen, we need to build the full
4300 arguments containing {int} as the innermost level. Outer levels,
4301 available when not appearing as default template argument, can be
4302 obtained from `current_template_args ()'.
4304 Suppose that TT is later substituted with std::vector. The above
4305 instantiation is `TT<int, std::allocator<T> >' with TT at
4306 level 1, and T at level 2, while the template arguments at level 1
4307 becomes {std::vector} and the inner level 2 is {int}. */
4309 if (current_template_parms)
4310 arglist = add_to_template_args (current_template_args (), arglist);
4312 arglist2 = coerce_template_parms (parmlist, arglist, template,
4313 complain, /*require_all_args=*/1);
4314 if (arglist2 == error_mark_node
4315 || (!uses_template_parms (arglist2)
4316 && check_instantiated_args (template, arglist2, complain)))
4317 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4319 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4320 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4324 tree template_type = TREE_TYPE (template);
4327 tree found = NULL_TREE;
4331 int is_partial_instantiation;
4333 gen_tmpl = most_general_template (template);
4334 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4335 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4336 arg_depth = TMPL_ARGS_DEPTH (arglist);
4338 if (arg_depth == 1 && parm_depth > 1)
4340 /* We've been given an incomplete set of template arguments.
4343 template <class T> struct S1 {
4344 template <class U> struct S2 {};
4345 template <class U> struct S2<U*> {};
4348 we will be called with an ARGLIST of `U*', but the
4349 TEMPLATE will be `template <class T> template
4350 <class U> struct S1<T>::S2'. We must fill in the missing
4353 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4355 arg_depth = TMPL_ARGS_DEPTH (arglist);
4358 /* Now we should have enough arguments. */
4359 my_friendly_assert (parm_depth == arg_depth, 0);
4361 /* From here on, we're only interested in the most general
4363 template = gen_tmpl;
4365 /* Calculate the BOUND_ARGS. These will be the args that are
4366 actually tsubst'd into the definition to create the
4370 /* We have multiple levels of arguments to coerce, at once. */
4372 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4374 tree bound_args = make_tree_vec (parm_depth);
4376 for (i = saved_depth,
4377 t = DECL_TEMPLATE_PARMS (template);
4378 i > 0 && t != NULL_TREE;
4379 --i, t = TREE_CHAIN (t))
4381 tree a = coerce_template_parms (TREE_VALUE (t),
4383 complain, /*require_all_args=*/1);
4385 /* Don't process further if one of the levels fails. */
4386 if (a == error_mark_node)
4388 /* Restore the ARGLIST to its full size. */
4389 TREE_VEC_LENGTH (arglist) = saved_depth;
4390 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4393 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4395 /* We temporarily reduce the length of the ARGLIST so
4396 that coerce_template_parms will see only the arguments
4397 corresponding to the template parameters it is
4399 TREE_VEC_LENGTH (arglist)--;
4402 /* Restore the ARGLIST to its full size. */
4403 TREE_VEC_LENGTH (arglist) = saved_depth;
4405 arglist = bound_args;
4409 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4410 INNERMOST_TEMPLATE_ARGS (arglist),
4412 complain, /*require_all_args=*/1);
4414 if (arglist == error_mark_node)
4415 /* We were unable to bind the arguments. */
4416 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4418 /* In the scope of a template class, explicit references to the
4419 template class refer to the type of the template, not any
4420 instantiation of it. For example, in:
4422 template <class T> class C { void f(C<T>); }
4424 the `C<T>' is just the same as `C'. Outside of the
4425 class, however, such a reference is an instantiation. */
4426 if (comp_template_args (TYPE_TI_ARGS (template_type),
4429 found = template_type;
4431 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4435 for (ctx = current_class_type;
4436 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4438 ? TYPE_CONTEXT (ctx)
4439 : DECL_CONTEXT (ctx)))
4440 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4443 /* We're not in the scope of the class, so the
4444 TEMPLATE_TYPE is not the type we want after all. */
4450 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4452 for (tp = &DECL_TEMPLATE_INSTANTIATIONS (template);
4454 tp = &TREE_CHAIN (*tp))
4455 if (comp_template_args (TREE_PURPOSE (*tp), arglist))
4459 /* Use the move-to-front heuristic to speed up future
4461 *tp = TREE_CHAIN (*tp);
4463 = DECL_TEMPLATE_INSTANTIATIONS (template);
4464 DECL_TEMPLATE_INSTANTIATIONS (template) = found;
4466 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, TREE_VALUE (found));
4469 /* This type is a "partial instantiation" if any of the template
4470 arguments still involve template parameters. Note that we set
4471 IS_PARTIAL_INSTANTIATION for partial specializations as
4473 is_partial_instantiation = uses_template_parms (arglist);
4475 /* If the deduced arguments are invalid, then the binding
4477 if (!is_partial_instantiation
4478 && check_instantiated_args (template,
4479 INNERMOST_TEMPLATE_ARGS (arglist),
4481 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4483 if (!is_partial_instantiation
4484 && !PRIMARY_TEMPLATE_P (template)
4485 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4487 found = xref_tag_from_type (TREE_TYPE (template),
4488 DECL_NAME (template),
4490 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4493 context = tsubst (DECL_CONTEXT (template), arglist,
4496 context = global_namespace;
4498 /* Create the type. */
4499 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4501 if (!is_partial_instantiation)
4503 set_current_access_from_decl (TYPE_NAME (template_type));
4504 t = start_enum (TYPE_IDENTIFIER (template_type));
4507 /* We don't want to call start_enum for this type, since
4508 the values for the enumeration constants may involve
4509 template parameters. And, no one should be interested
4510 in the enumeration constants for such a type. */
4511 t = make_node (ENUMERAL_TYPE);
4515 t = make_aggr_type (TREE_CODE (template_type));
4516 CLASSTYPE_DECLARED_CLASS (t)
4517 = CLASSTYPE_DECLARED_CLASS (template_type);
4518 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4519 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4521 /* A local class. Make sure the decl gets registered properly. */
4522 if (context == current_function_decl)
4523 pushtag (DECL_NAME (template), t, 0);
4526 /* If we called start_enum or pushtag above, this information
4527 will already be set up. */
4530 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4532 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4533 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4534 TYPE_STUB_DECL (t) = type_decl;
4535 DECL_SOURCE_LOCATION (type_decl)
4536 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4539 type_decl = TYPE_NAME (t);
4541 TREE_PRIVATE (type_decl)
4542 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4543 TREE_PROTECTED (type_decl)
4544 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4546 /* Set up the template information. We have to figure out which
4547 template is the immediate parent if this is a full
4549 if (parm_depth == 1 || is_partial_instantiation
4550 || !PRIMARY_TEMPLATE_P (template))
4551 /* This case is easy; there are no member templates involved. */
4555 /* This is a full instantiation of a member template. Look
4556 for a partial instantiation of which this is an instance. */
4558 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4559 found; found = TREE_CHAIN (found))
4562 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4564 /* We only want partial instantiations, here, not
4565 specializations or full instantiations. */
4566 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4567 || !uses_template_parms (TREE_VALUE (found)))
4570 /* Temporarily reduce by one the number of levels in the
4571 ARGLIST and in FOUND so as to avoid comparing the
4572 last set of arguments. */
4573 TREE_VEC_LENGTH (arglist)--;
4574 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4576 /* See if the arguments match. If they do, then TMPL is
4577 the partial instantiation we want. */
4578 success = comp_template_args (TREE_PURPOSE (found), arglist);
4580 /* Restore the argument vectors to their full size. */
4581 TREE_VEC_LENGTH (arglist)++;
4582 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4593 /* There was no partial instantiation. This happens
4594 where C<T> is a member template of A<T> and it's used
4597 template <typename T> struct B { A<T>::C<int> m; };
4600 Create the partial instantiation.
4602 TREE_VEC_LENGTH (arglist)--;
4603 found = tsubst (template, arglist, complain, NULL_TREE);
4604 TREE_VEC_LENGTH (arglist)++;
4608 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4609 DECL_TEMPLATE_INSTANTIATIONS (template)
4610 = tree_cons (arglist, t,
4611 DECL_TEMPLATE_INSTANTIATIONS (template));
4613 if (TREE_CODE (t) == ENUMERAL_TYPE
4614 && !is_partial_instantiation)
4615 /* Now that the type has been registered on the instantiations
4616 list, we set up the enumerators. Because the enumeration
4617 constants may involve the enumeration type itself, we make
4618 sure to register the type first, and then create the
4619 constants. That way, doing tsubst_expr for the enumeration
4620 constants won't result in recursive calls here; we'll find
4621 the instantiation and exit above. */
4622 tsubst_enum (template_type, t, arglist);
4624 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4626 if (TREE_CODE (t) != ENUMERAL_TYPE)
4627 DECL_NAME (type_decl) = classtype_mangled_name (t);
4628 if (is_partial_instantiation)
4629 /* If the type makes use of template parameters, the
4630 code that generates debugging information will crash. */
4631 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4633 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4635 timevar_pop (TV_NAME_LOOKUP);
4645 /* Called from for_each_template_parm via walk_tree. */
4648 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4651 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4652 tree_fn_t fn = pfd->fn;
4653 void *data = pfd->data;
4656 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4657 return error_mark_node;
4659 switch (TREE_CODE (t))
4662 if (TYPE_PTRMEMFUNC_P (t))
4668 if (!TYPE_TEMPLATE_INFO (t))
4670 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4671 fn, data, pfd->visited))
4672 return error_mark_node;
4676 /* Since we're not going to walk subtrees, we have to do this
4678 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4680 return error_mark_node;
4684 /* Check the return type. */
4685 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4686 return error_mark_node;
4688 /* Check the parameter types. Since default arguments are not
4689 instantiated until they are needed, the TYPE_ARG_TYPES may
4690 contain expressions that involve template parameters. But,
4691 no-one should be looking at them yet. And, once they're
4692 instantiated, they don't contain template parameters, so
4693 there's no point in looking at them then, either. */
4697 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4698 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4700 return error_mark_node;
4702 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4703 want walk_tree walking into them itself. */
4709 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4711 return error_mark_node;
4716 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4717 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4719 return error_mark_node;
4724 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4725 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4727 return error_mark_node;
4728 if (DECL_CONTEXT (t)
4729 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4731 return error_mark_node;
4734 case BOUND_TEMPLATE_TEMPLATE_PARM:
4735 /* Record template parameters such as `T' inside `TT<T>'. */
4736 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4737 return error_mark_node;
4740 case TEMPLATE_TEMPLATE_PARM:
4741 case TEMPLATE_TYPE_PARM:
4742 case TEMPLATE_PARM_INDEX:
4743 if (fn && (*fn)(t, data))
4744 return error_mark_node;
4746 return error_mark_node;
4750 /* A template template parameter is encountered. */
4751 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4752 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4753 return error_mark_node;
4755 /* Already substituted template template parameter */
4761 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4762 data, pfd->visited))
4763 return error_mark_node;
4767 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4768 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4769 (TREE_TYPE (t)), fn, data,
4771 return error_mark_node;
4776 /* If there's no type, then this thing must be some expression
4777 involving template parameters. */
4778 if (!fn && !TREE_TYPE (t))
4779 return error_mark_node;
4784 case REINTERPRET_CAST_EXPR:
4785 case CONST_CAST_EXPR:
4786 case STATIC_CAST_EXPR:
4787 case DYNAMIC_CAST_EXPR:
4791 case PSEUDO_DTOR_EXPR:
4793 return error_mark_node;
4797 /* If we do not handle this case specially, we end up walking
4798 the BINFO hierarchy, which is circular, and therefore
4799 confuses walk_tree. */
4801 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4803 return error_mark_node;
4810 /* We didn't find any template parameters we liked. */
4814 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4815 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4816 call FN with the parameter and the DATA.
4817 If FN returns nonzero, the iteration is terminated, and
4818 for_each_template_parm returns 1. Otherwise, the iteration
4819 continues. If FN never returns a nonzero value, the value
4820 returned by for_each_template_parm is 0. If FN is NULL, it is
4821 considered to be the function which always returns 1. */
4824 for_each_template_parm (tree t, tree_fn_t fn, void* data, htab_t visited)
4826 struct pair_fn_data pfd;
4833 /* Walk the tree. (Conceptually, we would like to walk without
4834 duplicates, but for_each_template_parm_r recursively calls
4835 for_each_template_parm, so we would need to reorganize a fair
4836 bit to use walk_tree_without_duplicates, so we keep our own
4839 pfd.visited = visited;
4841 pfd.visited = htab_create (37, htab_hash_pointer, htab_eq_pointer,
4843 result = walk_tree (&t,
4844 for_each_template_parm_r,
4846 pfd.visited) != NULL_TREE;
4850 htab_delete (pfd.visited);
4855 /* Returns true if T depends on any template parameter. */
4858 uses_template_parms (tree t)
4861 int saved_processing_template_decl;
4863 saved_processing_template_decl = processing_template_decl;
4864 if (!saved_processing_template_decl)
4865 processing_template_decl = 1;
4867 dependent_p = dependent_type_p (t);
4868 else if (TREE_CODE (t) == TREE_VEC)
4869 dependent_p = any_dependent_template_arguments_p (t);
4870 else if (TREE_CODE (t) == TREE_LIST)
4871 dependent_p = (uses_template_parms (TREE_VALUE (t))
4872 || uses_template_parms (TREE_CHAIN (t)));
4875 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4876 || TREE_CODE (t) == OVERLOAD
4877 || TREE_CODE (t) == BASELINK
4878 || TREE_CODE_CLASS (TREE_CODE (t)) == 'c')
4879 dependent_p = (type_dependent_expression_p (t)
4880 || value_dependent_expression_p (t));
4881 else if (t == error_mark_node)
4882 dependent_p = false;
4885 processing_template_decl = saved_processing_template_decl;
4890 /* Returns true if T depends on any template parameter with level LEVEL. */
4893 uses_template_parms_level (tree t, int level)
4895 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4898 static int tinst_depth;
4899 extern int max_tinst_depth;
4900 #ifdef GATHER_STATISTICS
4903 static int tinst_level_tick;
4904 static int last_template_error_tick;
4906 /* We're starting to instantiate D; record the template instantiation context
4907 for diagnostics and to restore it later. */
4910 push_tinst_level (tree d)
4914 if (tinst_depth >= max_tinst_depth)
4916 /* If the instantiation in question still has unbound template parms,
4917 we don't really care if we can't instantiate it, so just return.
4918 This happens with base instantiation for implicit `typename'. */
4919 if (uses_template_parms (d))
4922 last_template_error_tick = tinst_level_tick;
4923 error ("template instantiation depth exceeds maximum of %d (use -ftemplate-depth-NN to increase the maximum) instantiating `%D'",
4924 max_tinst_depth, d);
4926 print_instantiation_context ();
4931 new = make_tinst_level (d, input_location);
4932 TREE_CHAIN (new) = current_tinst_level;
4933 current_tinst_level = new;
4936 #ifdef GATHER_STATISTICS
4937 if (tinst_depth > depth_reached)
4938 depth_reached = tinst_depth;
4945 /* We're done instantiating this template; return to the instantiation
4949 pop_tinst_level (void)
4951 tree old = current_tinst_level;
4953 /* Restore the filename and line number stashed away when we started
4954 this instantiation. */
4955 input_location = TINST_LOCATION (old);
4956 extract_interface_info ();
4958 current_tinst_level = TREE_CHAIN (old);
4963 /* We're instantiating a deferred template; restore the template
4964 instantiation context in which the instantiation was requested, which
4965 is one step out from LEVEL. */
4968 reopen_tinst_level (tree level)
4973 for (t = level; t; t = TREE_CHAIN (t))
4976 current_tinst_level = level;
4980 /* Return the outermost template instantiation context, for use with
4981 -falt-external-templates. */
4984 tinst_for_decl (void)
4986 tree p = current_tinst_level;
4989 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
4994 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4995 vector of template arguments, as for tsubst.
4997 Returns an appropriate tsubst'd friend declaration. */
5000 tsubst_friend_function (tree decl, tree args)
5003 location_t saved_loc = input_location;
5005 input_location = DECL_SOURCE_LOCATION (decl);
5007 if (TREE_CODE (decl) == FUNCTION_DECL
5008 && DECL_TEMPLATE_INSTANTIATION (decl)
5009 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5010 /* This was a friend declared with an explicit template
5011 argument list, e.g.:
5015 to indicate that f was a template instantiation, not a new
5016 function declaration. Now, we have to figure out what
5017 instantiation of what template. */
5019 tree template_id, arglist, fns;
5022 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5024 /* Friend functions are looked up in the containing namespace scope.
5025 We must enter that scope, to avoid finding member functions of the
5026 current cless with same name. */
5027 push_nested_namespace (ns);
5028 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5029 tf_error | tf_warning, NULL_TREE);
5030 pop_nested_namespace (ns);
5031 arglist = tsubst (DECL_TI_ARGS (decl), args,
5032 tf_error | tf_warning, NULL_TREE);
5033 template_id = lookup_template_function (fns, arglist);
5035 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5036 tmpl = determine_specialization (template_id, new_friend,
5038 /*need_member_template=*/0,
5039 TREE_VEC_LENGTH (args));
5040 new_friend = instantiate_template (tmpl, new_args, tf_error);
5044 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5046 /* The NEW_FRIEND will look like an instantiation, to the
5047 compiler, but is not an instantiation from the point of view of
5048 the language. For example, we might have had:
5050 template <class T> struct S {
5051 template <class U> friend void f(T, U);
5054 Then, in S<int>, template <class U> void f(int, U) is not an
5055 instantiation of anything. */
5056 if (new_friend == error_mark_node)
5057 return error_mark_node;
5059 DECL_USE_TEMPLATE (new_friend) = 0;
5060 if (TREE_CODE (decl) == TEMPLATE_DECL)
5062 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5063 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5064 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5067 /* The mangled name for the NEW_FRIEND is incorrect. The function
5068 is not a template instantiation and should not be mangled like
5069 one. Therefore, we forget the mangling here; we'll recompute it
5070 later if we need it. */
5071 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5073 SET_DECL_RTL (new_friend, NULL_RTX);
5074 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5077 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5080 tree new_friend_template_info;
5081 tree new_friend_result_template_info;
5083 int new_friend_is_defn;
5085 /* We must save some information from NEW_FRIEND before calling
5086 duplicate decls since that function will free NEW_FRIEND if
5088 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5089 new_friend_is_defn =
5090 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5091 (template_for_substitution (new_friend)))
5093 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5095 /* This declaration is a `primary' template. */
5096 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5098 new_friend_result_template_info
5099 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5102 new_friend_result_template_info = NULL_TREE;
5104 /* Inside pushdecl_namespace_level, we will push into the
5105 current namespace. However, the friend function should go
5106 into the namespace of the template. */
5107 ns = decl_namespace_context (new_friend);
5108 push_nested_namespace (ns);
5109 old_decl = pushdecl_namespace_level (new_friend);
5110 pop_nested_namespace (ns);
5112 if (old_decl != new_friend)
5114 /* This new friend declaration matched an existing
5115 declaration. For example, given:
5117 template <class T> void f(T);
5118 template <class U> class C {
5119 template <class T> friend void f(T) {}
5122 the friend declaration actually provides the definition
5123 of `f', once C has been instantiated for some type. So,
5124 old_decl will be the out-of-class template declaration,
5125 while new_friend is the in-class definition.
5127 But, if `f' was called before this point, the
5128 instantiation of `f' will have DECL_TI_ARGS corresponding
5129 to `T' but not to `U', references to which might appear
5130 in the definition of `f'. Previously, the most general
5131 template for an instantiation of `f' was the out-of-class
5132 version; now it is the in-class version. Therefore, we
5133 run through all specialization of `f', adding to their
5134 DECL_TI_ARGS appropriately. In particular, they need a
5135 new set of outer arguments, corresponding to the
5136 arguments for this class instantiation.
5138 The same situation can arise with something like this:
5141 template <class T> class C {
5145 when `C<int>' is instantiated. Now, `f(int)' is defined
5148 if (!new_friend_is_defn)
5149 /* On the other hand, if the in-class declaration does
5150 *not* provide a definition, then we don't want to alter
5151 existing definitions. We can just leave everything
5156 /* Overwrite whatever template info was there before, if
5157 any, with the new template information pertaining to
5159 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5161 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5162 reregister_specialization (new_friend,
5163 most_general_template (old_decl),
5168 tree new_friend_args;
5170 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5171 = new_friend_result_template_info;
5173 new_friend_args = TI_ARGS (new_friend_template_info);
5174 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5178 tree spec = TREE_VALUE (t);
5181 = add_outermost_template_args (new_friend_args,
5182 DECL_TI_ARGS (spec));
5185 /* Now, since specializations are always supposed to
5186 hang off of the most general template, we must move
5188 t = most_general_template (old_decl);
5191 DECL_TEMPLATE_SPECIALIZATIONS (t)
5192 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5193 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5194 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5199 /* The information from NEW_FRIEND has been merged into OLD_DECL
5200 by duplicate_decls. */
5201 new_friend = old_decl;
5204 else if (COMPLETE_TYPE_P (DECL_CONTEXT (new_friend)))
5206 /* Check to see that the declaration is really present, and,
5207 possibly obtain an improved declaration. */
5208 tree fn = check_classfn (DECL_CONTEXT (new_friend),
5209 new_friend, NULL_TREE);
5216 input_location = saved_loc;
5220 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5221 template arguments, as for tsubst.
5223 Returns an appropriate tsubst'd friend type or error_mark_node on
5227 tsubst_friend_class (tree friend_tmpl, tree args)
5233 context = DECL_CONTEXT (friend_tmpl);
5237 if (TREE_CODE (context) == NAMESPACE_DECL)
5238 push_nested_namespace (context);
5240 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5243 /* First, we look for a class template. */
5244 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5246 /* But, if we don't find one, it might be because we're in a
5247 situation like this:
5255 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5256 for `S<int>', not the TEMPLATE_DECL. */
5257 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5259 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5260 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5263 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5265 /* The friend template has already been declared. Just
5266 check to see that the declarations match, and install any new
5267 default parameters. We must tsubst the default parameters,
5268 of course. We only need the innermost template parameters
5269 because that is all that redeclare_class_template will look
5271 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5272 > TMPL_ARGS_DEPTH (args))
5275 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5276 args, tf_error | tf_warning);
5277 redeclare_class_template (TREE_TYPE (tmpl), parms);
5280 friend_type = TREE_TYPE (tmpl);
5284 /* The friend template has not already been declared. In this
5285 case, the instantiation of the template class will cause the
5286 injection of this template into the global scope. */
5287 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5289 /* The new TMPL is not an instantiation of anything, so we
5290 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5291 the new type because that is supposed to be the corresponding
5292 template decl, i.e., TMPL. */
5293 DECL_USE_TEMPLATE (tmpl) = 0;
5294 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5295 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5296 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5297 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5299 /* Inject this template into the global scope. */
5300 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5305 if (TREE_CODE (context) == NAMESPACE_DECL)
5306 pop_nested_namespace (context);
5308 pop_nested_class ();
5314 /* Returns zero if TYPE cannot be completed later due to circularity.
5315 Otherwise returns one. */
5318 can_complete_type_without_circularity (tree type)
5320 if (type == NULL_TREE || type == error_mark_node)
5322 else if (COMPLETE_TYPE_P (type))
5324 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5325 return can_complete_type_without_circularity (TREE_TYPE (type));
5326 else if (CLASS_TYPE_P (type)
5327 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5334 instantiate_class_template (tree type)
5336 tree template, args, pattern, t, member;
5341 if (type == error_mark_node)
5342 return error_mark_node;
5344 if (TYPE_BEING_DEFINED (type)
5345 || COMPLETE_TYPE_P (type)
5346 || dependent_type_p (type))
5349 /* Figure out which template is being instantiated. */
5350 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5351 my_friendly_assert (TREE_CODE (template) == TEMPLATE_DECL, 279);
5353 /* Figure out which arguments are being used to do the
5355 args = CLASSTYPE_TI_ARGS (type);
5357 /* Determine what specialization of the original template to
5359 t = most_specialized_class (template, args);
5360 if (t == error_mark_node)
5362 const char *str = "candidates are:";
5363 error ("ambiguous class template instantiation for `%#T'", type);
5364 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5367 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5369 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5373 TYPE_BEING_DEFINED (type) = 1;
5374 return error_mark_node;
5378 pattern = TREE_TYPE (t);
5380 pattern = TREE_TYPE (template);
5382 /* If the template we're instantiating is incomplete, then clearly
5383 there's nothing we can do. */
5384 if (!COMPLETE_TYPE_P (pattern))
5387 /* If we've recursively instantiated too many templates, stop. */
5388 if (! push_tinst_level (type))
5391 /* Now we're really doing the instantiation. Mark the type as in
5392 the process of being defined. */
5393 TYPE_BEING_DEFINED (type) = 1;
5395 /* We may be in the middle of deferred access check. Disable
5397 push_deferring_access_checks (dk_no_deferred);
5399 push_to_top_level ();
5403 /* This TYPE is actually an instantiation of a partial
5404 specialization. We replace the innermost set of ARGS with
5405 the arguments appropriate for substitution. For example,
5408 template <class T> struct S {};
5409 template <class T> struct S<T*> {};
5411 and supposing that we are instantiating S<int*>, ARGS will
5412 present be {int*} but we need {int}. */
5414 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5417 /* If there were multiple levels in ARGS, replacing the
5418 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5419 want, so we make a copy first. */
5420 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5422 args = copy_node (args);
5423 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5429 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5431 /* Set the input location to the template definition. This is needed
5432 if tsubsting causes an error. */
5433 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (pattern));
5435 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5436 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5437 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5438 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5439 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5440 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5441 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5442 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5443 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5444 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5445 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5446 TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
5447 = TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (pattern);
5448 TYPE_USES_MULTIPLE_INHERITANCE (type)
5449 = TYPE_USES_MULTIPLE_INHERITANCE (pattern);
5450 TYPE_USES_VIRTUAL_BASECLASSES (type)
5451 = TYPE_USES_VIRTUAL_BASECLASSES (pattern);
5452 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5453 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5454 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5455 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5456 if (ANON_AGGR_TYPE_P (pattern))
5457 SET_ANON_AGGR_TYPE_P (type);
5459 pbinfo = TYPE_BINFO (pattern);
5461 #ifdef ENABLE_CHECKING
5462 if (DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5463 && ! COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5464 && ! TYPE_BEING_DEFINED (TYPE_CONTEXT (type)))
5465 /* We should never instantiate a nested class before its enclosing
5466 class; we need to look up the nested class by name before we can
5467 instantiate it, and that lookup should instantiate the enclosing
5472 base_list = NULL_TREE;
5473 if (BINFO_N_BASE_BINFOS (pbinfo))
5476 tree context = TYPE_CONTEXT (type);
5480 /* We must enter the scope containing the type, as that is where
5481 the accessibility of types named in dependent bases are
5483 pop_p = push_scope (context ? context : global_namespace);
5485 /* Substitute into each of the bases to determine the actual
5487 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5490 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5492 /* Substitute to figure out the base class. */
5493 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5494 if (base == error_mark_node)
5497 base_list = tree_cons (access, base, base_list);
5498 if (BINFO_VIRTUAL_P (pbase_binfo))
5499 TREE_TYPE (base_list) = integer_type_node;
5502 /* The list is now in reverse order; correct that. */
5503 base_list = nreverse (base_list);
5506 pop_scope (context ? context : global_namespace);
5508 /* Now call xref_basetypes to set up all the base-class
5510 xref_basetypes (type, base_list);
5513 /* Now that our base classes are set up, enter the scope of the
5514 class, so that name lookups into base classes, etc. will work
5515 correctly. This is precisely analogous to what we do in
5516 begin_class_definition when defining an ordinary non-template
5520 /* Now members are processed in the order of declaration. */
5521 for (member = CLASSTYPE_DECL_LIST (pattern);
5522 member; member = TREE_CHAIN (member))
5524 tree t = TREE_VALUE (member);
5526 if (TREE_PURPOSE (member))
5530 /* Build new CLASSTYPE_NESTED_UTDS. */
5533 tree name = TYPE_IDENTIFIER (tag);
5536 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5537 if (newtag == error_mark_node)
5540 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5542 if (TYPE_LANG_SPECIFIC (tag) && CLASSTYPE_IS_TEMPLATE (tag))
5543 /* Unfortunately, lookup_template_class sets
5544 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5545 instantiation (i.e., for the type of a member
5546 template class nested within a template class.)
5547 This behavior is required for
5548 maybe_process_partial_specialization to work
5549 correctly, but is not accurate in this case;
5550 the TAG is not an instantiation of anything.
5551 (The corresponding TEMPLATE_DECL is an
5552 instantiation, but the TYPE is not.) */
5553 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5555 /* Now, we call pushtag to put this NEWTAG into the scope of
5556 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5557 pushtag calling push_template_decl. We don't have to do
5558 this for enums because it will already have been done in
5561 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5562 pushtag (name, newtag, /*globalize=*/0);
5565 else if (TREE_CODE (t) == FUNCTION_DECL
5566 || DECL_FUNCTION_TEMPLATE_P (t))
5568 /* Build new TYPE_METHODS. */
5571 if (TREE_CODE (t) == TEMPLATE_DECL)
5572 ++processing_template_decl;
5573 r = tsubst (t, args, tf_error, NULL_TREE);
5574 if (TREE_CODE (t) == TEMPLATE_DECL)
5575 --processing_template_decl;
5576 set_current_access_from_decl (r);
5577 grok_special_member_properties (r);
5578 finish_member_declaration (r);
5582 /* Build new TYPE_FIELDS. */
5584 if (TREE_CODE (t) != CONST_DECL)
5588 /* The the file and line for this declaration, to
5589 assist in error message reporting. Since we
5590 called push_tinst_level above, we don't need to
5592 input_location = DECL_SOURCE_LOCATION (t);
5594 if (TREE_CODE (t) == TEMPLATE_DECL)
5595 ++processing_template_decl;
5596 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5597 if (TREE_CODE (t) == TEMPLATE_DECL)
5598 --processing_template_decl;
5599 if (TREE_CODE (r) == VAR_DECL)
5603 if (DECL_INITIALIZED_IN_CLASS_P (r))
5604 init = tsubst_expr (DECL_INITIAL (t), args,
5605 tf_error | tf_warning, NULL_TREE);
5609 finish_static_data_member_decl
5610 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5612 if (DECL_INITIALIZED_IN_CLASS_P (r))
5613 check_static_variable_definition (r, TREE_TYPE (r));
5615 else if (TREE_CODE (r) == FIELD_DECL)
5617 /* Determine whether R has a valid type and can be
5618 completed later. If R is invalid, then it is
5619 replaced by error_mark_node so that it will not be
5620 added to TYPE_FIELDS. */
5621 tree rtype = TREE_TYPE (r);
5622 if (can_complete_type_without_circularity (rtype))
5623 complete_type (rtype);
5625 if (!COMPLETE_TYPE_P (rtype))
5627 cxx_incomplete_type_error (r, rtype);
5628 r = error_mark_node;
5632 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5633 such a thing will already have been added to the field
5634 list by tsubst_enum in finish_member_declaration in the
5635 CLASSTYPE_NESTED_UTDS case above. */
5636 if (!(TREE_CODE (r) == TYPE_DECL
5637 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5638 && DECL_ARTIFICIAL (r)))
5640 set_current_access_from_decl (r);
5641 finish_member_declaration (r);
5648 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5650 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5652 tree friend_type = t;
5653 tree new_friend_type;
5655 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5656 new_friend_type = tsubst_friend_class (friend_type, args);
5657 else if (uses_template_parms (friend_type))
5658 new_friend_type = tsubst (friend_type, args,
5659 tf_error | tf_warning, NULL_TREE);
5660 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5661 new_friend_type = friend_type;
5664 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5666 /* The call to xref_tag_from_type does injection for friend
5668 push_nested_namespace (ns);
5670 xref_tag_from_type (friend_type, NULL_TREE, 1);
5671 pop_nested_namespace (ns);
5674 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5675 /* Trick make_friend_class into realizing that the friend
5676 we're adding is a template, not an ordinary class. It's
5677 important that we use make_friend_class since it will
5678 perform some error-checking and output cross-reference
5680 ++processing_template_decl;
5682 if (new_friend_type != error_mark_node)
5683 make_friend_class (type, new_friend_type,
5684 /*complain=*/false);
5686 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5687 --processing_template_decl;
5691 /* Build new DECL_FRIENDLIST. */
5694 if (TREE_CODE (t) == TEMPLATE_DECL)
5696 ++processing_template_decl;
5697 push_deferring_access_checks (dk_no_check);
5700 r = tsubst_friend_function (t, args);
5701 add_friend (type, r, /*complain=*/false);
5702 if (TREE_CODE (t) == TEMPLATE_DECL)
5704 pop_deferring_access_checks ();
5705 --processing_template_decl;
5711 /* Set the file and line number information to whatever is given for
5712 the class itself. This puts error messages involving generated
5713 implicit functions at a predictable point, and the same point
5714 that would be used for non-template classes. */
5715 typedecl = TYPE_MAIN_DECL (type);
5716 input_location = DECL_SOURCE_LOCATION (typedecl);
5718 unreverse_member_declarations (type);
5719 finish_struct_1 (type);
5720 TYPE_BEING_DEFINED (type) = 0;
5722 /* Now that the class is complete, instantiate default arguments for
5723 any member functions. We don't do this earlier because the
5724 default arguments may reference members of the class. */
5725 if (!PRIMARY_TEMPLATE_P (template))
5726 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5727 if (TREE_CODE (t) == FUNCTION_DECL
5728 /* Implicitly generated member functions will not have template
5729 information; they are not instantiations, but instead are
5730 created "fresh" for each instantiation. */
5731 && DECL_TEMPLATE_INFO (t))
5732 tsubst_default_arguments (t);
5735 pop_from_top_level ();
5736 pop_deferring_access_checks ();
5739 /* The vtable for a template class can be emitted in any translation
5740 unit in which the class is instantiated. When there is no key
5741 method, however, finish_struct_1 will already have added TYPE to
5742 the keyed_classes list. */
5743 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5744 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5750 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5756 else if (TYPE_P (t))
5757 r = tsubst (t, args, complain, in_decl);
5760 r = tsubst_expr (t, args, complain, in_decl);
5762 if (!uses_template_parms (r))
5764 /* Sometimes, one of the args was an expression involving a
5765 template constant parameter, like N - 1. Now that we've
5766 tsubst'd, we might have something like 2 - 1. This will
5767 confuse lookup_template_class, so we do constant folding
5768 here. We have to unset processing_template_decl, to fool
5769 tsubst_copy_and_build() into building an actual tree. */
5771 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5772 as simple as it's going to get, and trying to reprocess
5773 the trees will break. Once tsubst_expr et al DTRT for
5774 non-dependent exprs, this code can go away, as the type
5775 will always be set. */
5778 int saved_processing_template_decl = processing_template_decl;
5779 processing_template_decl = 0;
5780 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5781 tf_error, /*in_decl=*/NULL_TREE,
5782 /*function_p=*/false);
5783 processing_template_decl = saved_processing_template_decl;
5791 /* Substitute ARGS into the vector or list of template arguments T. */
5794 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5796 int len = TREE_VEC_LENGTH (t);
5797 int need_new = 0, i;
5798 tree *elts = alloca (len * sizeof (tree));
5800 for (i = 0; i < len; i++)
5802 tree orig_arg = TREE_VEC_ELT (t, i);
5805 if (TREE_CODE (orig_arg) == TREE_VEC)
5806 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5808 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5810 if (new_arg == error_mark_node)
5811 return error_mark_node;
5814 if (new_arg != orig_arg)
5821 t = make_tree_vec (len);
5822 for (i = 0; i < len; i++)
5823 TREE_VEC_ELT (t, i) = elts[i];
5828 /* Return the result of substituting ARGS into the template parameters
5829 given by PARMS. If there are m levels of ARGS and m + n levels of
5830 PARMS, then the result will contain n levels of PARMS. For
5831 example, if PARMS is `template <class T> template <class U>
5832 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5833 result will be `template <int*, double, class V>'. */
5836 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5841 for (new_parms = &r;
5842 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5843 new_parms = &(TREE_CHAIN (*new_parms)),
5844 parms = TREE_CHAIN (parms))
5847 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5850 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5852 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5853 tree default_value = TREE_PURPOSE (tuple);
5854 tree parm_decl = TREE_VALUE (tuple);
5856 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5857 default_value = tsubst_template_arg (default_value, args,
5858 complain, NULL_TREE);
5860 tuple = build_tree_list (default_value, parm_decl);
5861 TREE_VEC_ELT (new_vec, i) = tuple;
5865 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
5866 - TMPL_ARGS_DEPTH (args)),
5867 new_vec, NULL_TREE);
5873 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5874 type T. If T is not an aggregate or enumeration type, it is
5875 handled as if by tsubst. IN_DECL is as for tsubst. If
5876 ENTERING_SCOPE is nonzero, T is the context for a template which
5877 we are presently tsubst'ing. Return the substituted value. */
5880 tsubst_aggr_type (tree t,
5882 tsubst_flags_t complain,
5889 switch (TREE_CODE (t))
5892 if (TYPE_PTRMEMFUNC_P (t))
5893 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
5895 /* Else fall through. */
5898 if (TYPE_TEMPLATE_INFO (t))
5904 /* First, determine the context for the type we are looking
5906 context = TYPE_CONTEXT (t);
5908 context = tsubst_aggr_type (context, args, complain,
5909 in_decl, /*entering_scope=*/1);
5911 /* Then, figure out what arguments are appropriate for the
5912 type we are trying to find. For example, given:
5914 template <class T> struct S;
5915 template <class T, class U> void f(T, U) { S<U> su; }
5917 and supposing that we are instantiating f<int, double>,
5918 then our ARGS will be {int, double}, but, when looking up
5919 S we only want {double}. */
5920 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
5922 if (argvec == error_mark_node)
5923 return error_mark_node;
5925 r = lookup_template_class (t, argvec, in_decl, context,
5926 entering_scope, complain);
5928 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
5931 /* This is not a template type, so there's nothing to do. */
5935 return tsubst (t, args, complain, in_decl);
5939 /* Substitute into the default argument ARG (a default argument for
5940 FN), which has the indicated TYPE. */
5943 tsubst_default_argument (tree fn, tree type, tree arg)
5945 /* This default argument came from a template. Instantiate the
5946 default argument here, not in tsubst. In the case of
5955 we must be careful to do name lookup in the scope of S<T>,
5956 rather than in the current class. */
5957 push_access_scope (fn);
5958 /* The default argument expression should not be considered to be
5959 within the scope of FN. Since push_access_scope sets
5960 current_function_decl, we must explicitly clear it here. */
5961 current_function_decl = NULL_TREE;
5963 push_deferring_access_checks(dk_no_deferred);
5964 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
5965 tf_error | tf_warning, NULL_TREE);
5966 pop_deferring_access_checks();
5968 pop_access_scope (fn);
5970 /* Make sure the default argument is reasonable. */
5971 arg = check_default_argument (type, arg);
5976 /* Substitute into all the default arguments for FN. */
5979 tsubst_default_arguments (tree fn)
5984 tmpl_args = DECL_TI_ARGS (fn);
5986 /* If this function is not yet instantiated, we certainly don't need
5987 its default arguments. */
5988 if (uses_template_parms (tmpl_args))
5991 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
5993 arg = TREE_CHAIN (arg))
5994 if (TREE_PURPOSE (arg))
5995 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
5997 TREE_PURPOSE (arg));
6000 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
6001 (already computed) substitution of ARGS into TREE_TYPE (T), if
6002 appropriate. Return the result of the substitution. Issue error
6003 and warning messages under control of COMPLAIN. */
6006 tsubst_decl (tree t, tree args, tree type, tsubst_flags_t complain)
6008 location_t saved_loc;
6012 /* Set the filename and linenumber to improve error-reporting. */
6013 saved_loc = input_location;
6014 input_location = DECL_SOURCE_LOCATION (t);
6016 switch (TREE_CODE (t))
6020 /* We can get here when processing a member template function
6021 of a template class. */
6022 tree decl = DECL_TEMPLATE_RESULT (t);
6024 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
6026 if (!is_template_template_parm)
6028 /* We might already have an instance of this template.
6029 The ARGS are for the surrounding class type, so the
6030 full args contain the tsubst'd args for the context,
6031 plus the innermost args from the template decl. */
6032 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6033 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6034 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6037 full_args = tsubst_template_args (tmpl_args, args,
6040 /* tsubst_template_args doesn't copy the vector if
6041 nothing changed. But, *something* should have
6043 my_friendly_assert (full_args != tmpl_args, 0);
6045 spec = retrieve_specialization (t, full_args);
6046 if (spec != NULL_TREE)
6053 /* Make a new template decl. It will be similar to the
6054 original, but will record the current template arguments.
6055 We also create a new function declaration, which is just
6056 like the old one, but points to this new template, rather
6057 than the old one. */
6059 my_friendly_assert (DECL_LANG_SPECIFIC (r) != 0, 0);
6060 TREE_CHAIN (r) = NULL_TREE;
6062 if (is_template_template_parm)
6064 tree new_decl = tsubst (decl, args, complain, in_decl);
6065 DECL_TEMPLATE_RESULT (r) = new_decl;
6066 TREE_TYPE (r) = TREE_TYPE (new_decl);
6071 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6073 /*entering_scope=*/1);
6074 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6076 if (TREE_CODE (decl) == TYPE_DECL)
6078 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6079 if (new_type == error_mark_node)
6080 return error_mark_node;
6082 TREE_TYPE (r) = new_type;
6083 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6084 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6085 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6089 tree new_decl = tsubst (decl, args, complain, in_decl);
6090 if (new_decl == error_mark_node)
6091 return error_mark_node;
6093 DECL_TEMPLATE_RESULT (r) = new_decl;
6094 DECL_TI_TEMPLATE (new_decl) = r;
6095 TREE_TYPE (r) = TREE_TYPE (new_decl);
6096 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6099 SET_DECL_IMPLICIT_INSTANTIATION (r);
6100 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6101 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6103 /* The template parameters for this new template are all the
6104 template parameters for the old template, except the
6105 outermost level of parameters. */
6106 DECL_TEMPLATE_PARMS (r)
6107 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6110 if (PRIMARY_TEMPLATE_P (t))
6111 DECL_PRIMARY_TEMPLATE (r) = r;
6113 if (TREE_CODE (decl) != TYPE_DECL)
6114 /* Record this non-type partial instantiation. */
6115 register_specialization (r, t,
6116 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6123 tree argvec = NULL_TREE;
6130 /* Nobody should be tsubst'ing into non-template functions. */
6131 my_friendly_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE, 0);
6133 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6138 /* If T is not dependent, just return it. We have to
6139 increment PROCESSING_TEMPLATE_DECL because
6140 value_dependent_expression_p assumes that nothing is
6141 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6142 ++processing_template_decl;
6143 dependent_p = value_dependent_expression_p (t);
6144 --processing_template_decl;
6148 /* Calculate the most general template of which R is a
6149 specialization, and the complete set of arguments used to
6151 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6152 argvec = tsubst_template_args (DECL_TI_ARGS
6153 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6154 args, complain, in_decl);
6156 /* Check to see if we already have this specialization. */
6157 spec = retrieve_specialization (gen_tmpl, argvec);
6165 /* We can see more levels of arguments than parameters if
6166 there was a specialization of a member template, like
6169 template <class T> struct S { template <class U> void f(); }
6170 template <> template <class U> void S<int>::f(U);
6172 Here, we'll be substituting into the specialization,
6173 because that's where we can find the code we actually
6174 want to generate, but we'll have enough arguments for
6175 the most general template.
6177 We also deal with the peculiar case:
6179 template <class T> struct S {
6180 template <class U> friend void f();
6182 template <class U> void f() {}
6184 template void f<double>();
6186 Here, the ARGS for the instantiation of will be {int,
6187 double}. But, we only need as many ARGS as there are
6188 levels of template parameters in CODE_PATTERN. We are
6189 careful not to get fooled into reducing the ARGS in
6192 template <class T> struct S { template <class U> void f(U); }
6193 template <class T> template <> void S<T>::f(int) {}
6195 which we can spot because the pattern will be a
6196 specialization in this case. */
6197 args_depth = TMPL_ARGS_DEPTH (args);
6199 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6200 if (args_depth > parms_depth
6201 && !DECL_TEMPLATE_SPECIALIZATION (t))
6202 args = get_innermost_template_args (args, parms_depth);
6206 /* This special case arises when we have something like this:
6208 template <class T> struct S {
6209 friend void f<int>(int, double);
6212 Here, the DECL_TI_TEMPLATE for the friend declaration
6213 will be an IDENTIFIER_NODE. We are being called from
6214 tsubst_friend_function, and we want only to create a
6215 new decl (R) with appropriate types so that we can call
6216 determine_specialization. */
6217 gen_tmpl = NULL_TREE;
6220 if (DECL_CLASS_SCOPE_P (t))
6222 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6226 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6227 complain, t, /*entering_scope=*/1);
6232 ctx = DECL_CONTEXT (t);
6234 type = tsubst (type, args, complain, in_decl);
6235 if (type == error_mark_node)
6236 return error_mark_node;
6238 /* We do NOT check for matching decls pushed separately at this
6239 point, as they may not represent instantiations of this
6240 template, and in any case are considered separate under the
6243 DECL_USE_TEMPLATE (r) = 0;
6244 TREE_TYPE (r) = type;
6245 /* Clear out the mangled name and RTL for the instantiation. */
6246 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6247 SET_DECL_RTL (r, NULL_RTX);
6248 DECL_INITIAL (r) = NULL_TREE;
6249 DECL_CONTEXT (r) = ctx;
6251 if (member && DECL_CONV_FN_P (r))
6252 /* Type-conversion operator. Reconstruct the name, in
6253 case it's the name of one of the template's parameters. */
6254 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6256 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6258 DECL_RESULT (r) = NULL_TREE;
6260 TREE_STATIC (r) = 0;
6261 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6262 DECL_EXTERNAL (r) = 1;
6263 /* If this is an instantiation of a function with internal
6264 linkage, we already know what object file linkage will be
6265 assigned to the instantiation. */
6266 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6267 DECL_DEFER_OUTPUT (r) = 0;
6268 TREE_CHAIN (r) = NULL_TREE;
6269 DECL_PENDING_INLINE_INFO (r) = 0;
6270 DECL_PENDING_INLINE_P (r) = 0;
6271 DECL_SAVED_TREE (r) = NULL_TREE;
6273 if (DECL_CLONED_FUNCTION (r))
6275 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6277 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6278 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6281 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6282 this in the special friend case mentioned above where
6283 GEN_TMPL is NULL. */
6286 DECL_TEMPLATE_INFO (r)
6287 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6288 SET_DECL_IMPLICIT_INSTANTIATION (r);
6289 register_specialization (r, gen_tmpl, argvec);
6291 /* We're not supposed to instantiate default arguments
6292 until they are called, for a template. But, for a
6295 template <class T> void f ()
6296 { extern void g(int i = T()); }
6298 we should do the substitution when the template is
6299 instantiated. We handle the member function case in
6300 instantiate_class_template since the default arguments
6301 might refer to other members of the class. */
6303 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6304 && !uses_template_parms (argvec))
6305 tsubst_default_arguments (r);
6308 /* Copy the list of befriending classes. */
6309 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6311 friends = &TREE_CHAIN (*friends))
6313 *friends = copy_node (*friends);
6314 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6319 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6321 maybe_retrofit_in_chrg (r);
6322 if (DECL_CONSTRUCTOR_P (r))
6323 grok_ctor_properties (ctx, r);
6324 /* If this is an instantiation of a member template, clone it.
6325 If it isn't, that'll be handled by
6326 clone_constructors_and_destructors. */
6327 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6328 clone_function_decl (r, /*update_method_vec_p=*/0);
6330 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6331 grok_op_properties (r, DECL_FRIEND_P (r),
6332 (complain & tf_error) != 0);
6334 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6335 SET_DECL_FRIEND_CONTEXT (r,
6336 tsubst (DECL_FRIEND_CONTEXT (t),
6337 args, complain, in_decl));
6344 if (DECL_TEMPLATE_PARM_P (t))
6345 SET_DECL_TEMPLATE_PARM_P (r);
6347 TREE_TYPE (r) = type;
6348 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6350 if (DECL_INITIAL (r))
6352 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6353 DECL_INITIAL (r) = TREE_TYPE (r);
6355 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6359 DECL_CONTEXT (r) = NULL_TREE;
6361 if (!DECL_TEMPLATE_PARM_P (r))
6362 DECL_ARG_TYPE (r) = type_passed_as (type);
6364 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6365 complain, TREE_CHAIN (t));
6372 TREE_TYPE (r) = type;
6373 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6375 /* We don't have to set DECL_CONTEXT here; it is set by
6376 finish_member_declaration. */
6377 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6379 TREE_CHAIN (r) = NULL_TREE;
6380 if (VOID_TYPE_P (type))
6381 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6388 /* It is not a dependent using decl any more. */
6389 TREE_TYPE (r) = void_type_node;
6391 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6393 = tsubst_copy (DECL_NAME (t), args, complain, in_decl);
6394 TREE_CHAIN (r) = NULL_TREE;
6399 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6400 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6402 /* If this is the canonical decl, we don't have to mess with
6403 instantiations, and often we can't (for typename, template
6404 type parms and such). Note that TYPE_NAME is not correct for
6405 the above test if we've copied the type for a typedef. */
6406 r = TYPE_NAME (type);
6414 tree argvec = NULL_TREE;
6415 tree gen_tmpl = NULL_TREE;
6417 tree tmpl = NULL_TREE;
6421 /* Assume this is a non-local variable. */
6424 if (TYPE_P (CP_DECL_CONTEXT (t)))
6425 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6427 in_decl, /*entering_scope=*/1);
6428 else if (DECL_NAMESPACE_SCOPE_P (t))
6429 ctx = DECL_CONTEXT (t);
6432 /* Subsequent calls to pushdecl will fill this in. */
6437 /* Check to see if we already have this specialization. */
6440 tmpl = DECL_TI_TEMPLATE (t);
6441 gen_tmpl = most_general_template (tmpl);
6442 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6443 spec = retrieve_specialization (gen_tmpl, argvec);
6446 spec = retrieve_local_specialization (t);
6455 if (TREE_CODE (r) == VAR_DECL)
6457 type = complete_type (type);
6458 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6459 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6461 else if (DECL_SELF_REFERENCE_P (t))
6462 SET_DECL_SELF_REFERENCE_P (r);
6463 TREE_TYPE (r) = type;
6464 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6465 DECL_CONTEXT (r) = ctx;
6466 /* Clear out the mangled name and RTL for the instantiation. */
6467 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6468 SET_DECL_RTL (r, NULL_RTX);
6470 /* Don't try to expand the initializer until someone tries to use
6471 this variable; otherwise we run into circular dependencies. */
6472 DECL_INITIAL (r) = NULL_TREE;
6473 SET_DECL_RTL (r, NULL_RTX);
6474 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6476 /* Even if the original location is out of scope, the newly
6477 substituted one is not. */
6478 if (TREE_CODE (r) == VAR_DECL)
6480 DECL_DEAD_FOR_LOCAL (r) = 0;
6481 DECL_INITIALIZED_P (r) = 0;
6486 /* A static data member declaration is always marked
6487 external when it is declared in-class, even if an
6488 initializer is present. We mimic the non-template
6490 DECL_EXTERNAL (r) = 1;
6492 register_specialization (r, gen_tmpl, argvec);
6493 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6494 SET_DECL_IMPLICIT_INSTANTIATION (r);
6497 register_local_specialization (r, t);
6499 TREE_CHAIN (r) = NULL_TREE;
6500 if (TREE_CODE (r) == VAR_DECL && VOID_TYPE_P (type))
6501 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6502 /* Compute the size, alignment, etc. of R. */
6511 /* Restore the file and line information. */
6512 input_location = saved_loc;
6517 /* Substitute into the ARG_TYPES of a function type. */
6520 tsubst_arg_types (tree arg_types,
6522 tsubst_flags_t complain,
6525 tree remaining_arg_types;
6528 if (!arg_types || arg_types == void_list_node)
6531 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6532 args, complain, in_decl);
6533 if (remaining_arg_types == error_mark_node)
6534 return error_mark_node;
6536 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6537 if (type == error_mark_node)
6538 return error_mark_node;
6539 if (VOID_TYPE_P (type))
6541 if (complain & tf_error)
6543 error ("invalid parameter type `%T'", type);
6545 cp_error_at ("in declaration `%D'", in_decl);
6547 return error_mark_node;
6550 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6551 top-level qualifiers as required. */
6552 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6554 /* Note that we do not substitute into default arguments here. The
6555 standard mandates that they be instantiated only when needed,
6556 which is done in build_over_call. */
6557 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6558 remaining_arg_types);
6562 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6563 *not* handle the exception-specification for FNTYPE, because the
6564 initial substitution of explicitly provided template parameters
6565 during argument deduction forbids substitution into the
6566 exception-specification:
6570 All references in the function type of the function template to the
6571 corresponding template parameters are replaced by the specified tem-
6572 plate argument values. If a substitution in a template parameter or
6573 in the function type of the function template results in an invalid
6574 type, type deduction fails. [Note: The equivalent substitution in
6575 exception specifications is done only when the function is instanti-
6576 ated, at which point a program is ill-formed if the substitution
6577 results in an invalid type.] */
6580 tsubst_function_type (tree t,
6582 tsubst_flags_t complain,
6589 /* The TYPE_CONTEXT is not used for function/method types. */
6590 my_friendly_assert (TYPE_CONTEXT (t) == NULL_TREE, 0);
6592 /* Substitute the return type. */
6593 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6594 if (return_type == error_mark_node)
6595 return error_mark_node;
6597 /* Substitute the argument types. */
6598 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6600 if (arg_types == error_mark_node)
6601 return error_mark_node;
6603 /* Construct a new type node and return it. */
6604 if (TREE_CODE (t) == FUNCTION_TYPE)
6605 fntype = build_function_type (return_type, arg_types);
6608 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6609 if (! IS_AGGR_TYPE (r))
6613 Type deduction may fail for any of the following
6616 -- Attempting to create "pointer to member of T" when T
6617 is not a class type. */
6618 if (complain & tf_error)
6619 error ("creating pointer to member function of non-class type `%T'",
6621 return error_mark_node;
6624 fntype = build_method_type_directly (r, return_type,
6625 TREE_CHAIN (arg_types));
6627 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6628 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6633 /* Substitute into the PARMS of a call-declarator. */
6636 tsubst_call_declarator_parms (tree parms,
6638 tsubst_flags_t complain,
6645 if (!parms || parms == void_list_node)
6648 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6649 args, complain, in_decl);
6651 /* Figure out the type of this parameter. */
6652 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6654 /* Figure out the default argument as well. Note that we use
6655 tsubst_expr since the default argument is really an expression. */
6656 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6658 /* Chain this parameter on to the front of those we have already
6659 processed. We don't use hash_tree_cons because that function
6660 doesn't check TREE_PARMLIST. */
6661 new_parms = tree_cons (defarg, type, new_parms);
6666 /* Take the tree structure T and replace template parameters used
6667 therein with the argument vector ARGS. IN_DECL is an associated
6668 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6669 Issue error and warning messages under control of COMPLAIN. Note
6670 that we must be relatively non-tolerant of extensions here, in
6671 order to preserve conformance; if we allow substitutions that
6672 should not be allowed, we may allow argument deductions that should
6673 not succeed, and therefore report ambiguous overload situations
6674 where there are none. In theory, we could allow the substitution,
6675 but indicate that it should have failed, and allow our caller to
6676 make sure that the right thing happens, but we don't try to do this
6679 This function is used for dealing with types, decls and the like;
6680 for expressions, use tsubst_expr or tsubst_copy. */
6683 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6687 if (t == NULL_TREE || t == error_mark_node
6688 || t == integer_type_node
6689 || t == void_type_node
6690 || t == char_type_node
6691 || TREE_CODE (t) == NAMESPACE_DECL)
6694 if (TREE_CODE (t) == IDENTIFIER_NODE)
6695 type = IDENTIFIER_TYPE_VALUE (t);
6697 type = TREE_TYPE (t);
6699 my_friendly_assert (type != unknown_type_node, 20030716);
6701 if (type && TREE_CODE (t) != FUNCTION_DECL
6702 && TREE_CODE (t) != TYPENAME_TYPE
6703 && TREE_CODE (t) != TEMPLATE_DECL
6704 && TREE_CODE (t) != IDENTIFIER_NODE
6705 && TREE_CODE (t) != FUNCTION_TYPE
6706 && TREE_CODE (t) != METHOD_TYPE)
6707 type = tsubst (type, args, complain, in_decl);
6708 if (type == error_mark_node)
6709 return error_mark_node;
6712 return tsubst_decl (t, args, type, complain);
6714 switch (TREE_CODE (t))
6719 return tsubst_aggr_type (t, args, complain, in_decl,
6720 /*entering_scope=*/0);
6723 case IDENTIFIER_NODE:
6735 if (t == integer_type_node)
6738 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6739 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6743 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6745 /* The array dimension behaves like a non-type template arg,
6746 in that we want to fold it as much as possible. */
6747 max = tsubst_template_arg (omax, args, complain, in_decl);
6748 if (!processing_template_decl)
6749 max = decl_constant_value (max);
6751 if (integer_zerop (omax))
6753 /* Still allow an explicit array of size zero. */
6755 pedwarn ("creating array with size zero");
6757 else if (integer_zerop (max)
6758 || (TREE_CODE (max) == INTEGER_CST
6759 && INT_CST_LT (max, integer_zero_node)))
6763 Type deduction may fail for any of the following
6766 Attempting to create an array with a size that is
6767 zero or negative. */
6768 if (complain & tf_error)
6769 error ("creating array with size zero (`%E')", max);
6771 return error_mark_node;
6774 return compute_array_index_type (NULL_TREE, max);
6777 case TEMPLATE_TYPE_PARM:
6778 case TEMPLATE_TEMPLATE_PARM:
6779 case BOUND_TEMPLATE_TEMPLATE_PARM:
6780 case TEMPLATE_PARM_INDEX:
6788 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6789 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6790 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6792 idx = TEMPLATE_TYPE_IDX (t);
6793 level = TEMPLATE_TYPE_LEVEL (t);
6797 idx = TEMPLATE_PARM_IDX (t);
6798 level = TEMPLATE_PARM_LEVEL (t);
6801 if (TREE_VEC_LENGTH (args) > 0)
6803 tree arg = NULL_TREE;
6805 levels = TMPL_ARGS_DEPTH (args);
6806 if (level <= levels)
6807 arg = TMPL_ARG (args, level, idx);
6809 if (arg == error_mark_node)
6810 return error_mark_node;
6811 else if (arg != NULL_TREE)
6813 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6815 my_friendly_assert (TYPE_P (arg), 0);
6816 return cp_build_qualified_type_real
6817 (arg, cp_type_quals (arg) | cp_type_quals (t),
6818 complain | tf_ignore_bad_quals);
6820 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6822 /* We are processing a type constructed from
6823 a template template parameter. */
6824 tree argvec = tsubst (TYPE_TI_ARGS (t),
6825 args, complain, in_decl);
6826 if (argvec == error_mark_node)
6827 return error_mark_node;
6829 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6830 we are resolving nested-types in the signature of
6831 a member function templates.
6832 Otherwise ARG is a TEMPLATE_DECL and is the real
6833 template to be instantiated. */
6834 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
6835 arg = TYPE_NAME (arg);
6837 r = lookup_template_class (arg,
6840 /*entering_scope=*/0,
6842 return cp_build_qualified_type_real
6843 (r, TYPE_QUALS (t), complain);
6846 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
6854 /* This can happen during the attempted tsubst'ing in
6855 unify. This means that we don't yet have any information
6856 about the template parameter in question. */
6859 /* If we get here, we must have been looking at a parm for a
6860 more deeply nested template. Make a new version of this
6861 template parameter, but with a lower level. */
6862 switch (TREE_CODE (t))
6864 case TEMPLATE_TYPE_PARM:
6865 case TEMPLATE_TEMPLATE_PARM:
6866 case BOUND_TEMPLATE_TEMPLATE_PARM:
6867 if (cp_type_quals (t))
6869 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
6870 r = cp_build_qualified_type_real
6871 (r, cp_type_quals (t),
6872 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6873 ? tf_ignore_bad_quals : 0));
6878 TEMPLATE_TYPE_PARM_INDEX (r)
6879 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
6881 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
6882 TYPE_MAIN_VARIANT (r) = r;
6883 TYPE_POINTER_TO (r) = NULL_TREE;
6884 TYPE_REFERENCE_TO (r) = NULL_TREE;
6886 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6888 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
6890 if (argvec == error_mark_node)
6891 return error_mark_node;
6893 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
6894 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
6899 case TEMPLATE_PARM_INDEX:
6900 r = reduce_template_parm_level (t, type, levels);
6912 tree purpose, value, chain;
6914 if (t == void_list_node)
6917 purpose = TREE_PURPOSE (t);
6920 purpose = tsubst (purpose, args, complain, in_decl);
6921 if (purpose == error_mark_node)
6922 return error_mark_node;
6924 value = TREE_VALUE (t);
6927 value = tsubst (value, args, complain, in_decl);
6928 if (value == error_mark_node)
6929 return error_mark_node;
6931 chain = TREE_CHAIN (t);
6932 if (chain && chain != void_type_node)
6934 chain = tsubst (chain, args, complain, in_decl);
6935 if (chain == error_mark_node)
6936 return error_mark_node;
6938 if (purpose == TREE_PURPOSE (t)
6939 && value == TREE_VALUE (t)
6940 && chain == TREE_CHAIN (t))
6942 return hash_tree_cons (purpose, value, chain);
6946 /* We should never be tsubsting a binfo. */
6950 /* A vector of template arguments. */
6951 my_friendly_assert (!type, 20040628);
6952 return tsubst_template_args (t, args, complain, in_decl);
6955 case REFERENCE_TYPE:
6957 enum tree_code code;
6959 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
6962 code = TREE_CODE (t);
6967 Type deduction may fail for any of the following
6970 -- Attempting to create a pointer to reference type.
6971 -- Attempting to create a reference to a reference type or
6972 a reference to void. */
6973 if (TREE_CODE (type) == REFERENCE_TYPE
6974 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
6976 static location_t last_loc;
6978 /* We keep track of the last time we issued this error
6979 message to avoid spewing a ton of messages during a
6980 single bad template instantiation. */
6981 if (complain & tf_error
6982 #ifdef USE_MAPPED_LOCATION
6983 && last_loc != input_location)
6985 && (last_loc.line != input_line
6986 || last_loc.file != input_filename))
6989 if (TREE_CODE (type) == VOID_TYPE)
6990 error ("forming reference to void");
6992 error ("forming %s to reference type `%T'",
6993 (code == POINTER_TYPE) ? "pointer" : "reference",
6995 last_loc = input_location;
6998 return error_mark_node;
7000 else if (code == POINTER_TYPE)
7002 r = build_pointer_type (type);
7003 if (TREE_CODE (type) == METHOD_TYPE)
7004 r = build_ptrmemfunc_type (r);
7007 r = build_reference_type (type);
7008 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7010 if (r != error_mark_node)
7011 /* Will this ever be needed for TYPE_..._TO values? */
7018 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7019 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7023 Type deduction may fail for any of the following
7026 -- Attempting to create "pointer to member of T" when T
7027 is not a class type. */
7028 if (complain & tf_error)
7029 error ("creating pointer to member of non-class type `%T'", r);
7030 return error_mark_node;
7032 if (TREE_CODE (type) == REFERENCE_TYPE)
7034 if (complain & tf_error)
7035 error ("creating pointer to member reference type `%T'", type);
7037 return error_mark_node;
7039 my_friendly_assert (TREE_CODE (type) != METHOD_TYPE, 20011231);
7040 if (TREE_CODE (type) == FUNCTION_TYPE)
7042 /* This is really a method type. The cv qualifiers of the
7043 this pointer should _not_ be determined by the cv
7044 qualifiers of the class type. They should be held
7045 somewhere in the FUNCTION_TYPE, but we don't do that at
7046 the moment. Consider
7047 typedef void (Func) () const;
7049 template <typename T1> void Foo (Func T1::*);
7054 method_type = build_method_type_directly (TYPE_MAIN_VARIANT (r),
7056 TYPE_ARG_TYPES (type));
7057 return build_ptrmemfunc_type (build_pointer_type (method_type));
7060 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7070 fntype = tsubst_function_type (t, args, complain, in_decl);
7071 if (fntype == error_mark_node)
7072 return error_mark_node;
7074 /* Substitute the exception specification. */
7075 raises = TYPE_RAISES_EXCEPTIONS (t);
7078 tree list = NULL_TREE;
7080 if (! TREE_VALUE (raises))
7083 for (; raises != NULL_TREE; raises = TREE_CHAIN (raises))
7085 tree spec = TREE_VALUE (raises);
7087 spec = tsubst (spec, args, complain, in_decl);
7088 if (spec == error_mark_node)
7090 list = add_exception_specifier (list, spec, complain);
7092 fntype = build_exception_variant (fntype, list);
7098 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7099 if (domain == error_mark_node)
7100 return error_mark_node;
7102 /* As an optimization, we avoid regenerating the array type if
7103 it will obviously be the same as T. */
7104 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7107 /* These checks should match the ones in grokdeclarator.
7111 The deduction may fail for any of the following reasons:
7113 -- Attempting to create an array with an element type that
7114 is void, a function type, or a reference type, or [DR337]
7115 an abstract class type. */
7116 if (TREE_CODE (type) == VOID_TYPE
7117 || TREE_CODE (type) == FUNCTION_TYPE
7118 || TREE_CODE (type) == REFERENCE_TYPE)
7120 if (complain & tf_error)
7121 error ("creating array of `%T'", type);
7122 return error_mark_node;
7124 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7126 if (complain & tf_error)
7127 error ("creating array of `%T', which is an abstract class type",
7129 return error_mark_node;
7132 r = build_cplus_array_type (type, domain);
7139 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7140 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7142 if (e1 == error_mark_node || e2 == error_mark_node)
7143 return error_mark_node;
7145 return fold (build (TREE_CODE (t), TREE_TYPE (t), e1, e2));
7151 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7152 if (e == error_mark_node)
7153 return error_mark_node;
7155 return fold (build (TREE_CODE (t), TREE_TYPE (t), e));
7160 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7161 in_decl, /*entering_scope=*/1);
7162 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7165 if (ctx == error_mark_node || f == error_mark_node)
7166 return error_mark_node;
7168 if (!IS_AGGR_TYPE (ctx))
7170 if (complain & tf_error)
7171 error ("`%T' is not a class, struct, or union type",
7173 return error_mark_node;
7175 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7177 /* Normally, make_typename_type does not require that the CTX
7178 have complete type in order to allow things like:
7180 template <class T> struct S { typename S<T>::X Y; };
7182 But, such constructs have already been resolved by this
7183 point, so here CTX really should have complete type, unless
7184 it's a partial instantiation. */
7185 ctx = complete_type (ctx);
7186 if (!COMPLETE_TYPE_P (ctx))
7188 if (complain & tf_error)
7189 cxx_incomplete_type_error (NULL_TREE, ctx);
7190 return error_mark_node;
7194 f = make_typename_type (ctx, f,
7195 (complain & tf_error) | tf_keep_type_decl);
7196 if (f == error_mark_node)
7198 if (TREE_CODE (f) == TYPE_DECL)
7200 complain |= tf_ignore_bad_quals;
7204 return cp_build_qualified_type_real
7205 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7208 case UNBOUND_CLASS_TEMPLATE:
7210 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7211 in_decl, /*entering_scope=*/1);
7212 tree name = TYPE_IDENTIFIER (t);
7214 if (ctx == error_mark_node || name == error_mark_node)
7215 return error_mark_node;
7217 return make_unbound_class_template (ctx, name, complain);
7227 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7228 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7229 if (e1 == error_mark_node || e2 == error_mark_node)
7230 return error_mark_node;
7232 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7237 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7238 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7239 if (e1 == error_mark_node || e2 == error_mark_node)
7240 return error_mark_node;
7242 return build_nt (TREE_CODE (t), e1, e2);
7249 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7250 complain, in_decl));
7251 return cp_build_qualified_type_real (type,
7253 | cp_type_quals (type),
7258 sorry ("use of `%s' in template",
7259 tree_code_name [(int) TREE_CODE (t)]);
7260 return error_mark_node;
7264 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7265 type of the expression on the left-hand side of the "." or "->"
7269 tsubst_baselink (tree baselink, tree object_type,
7270 tree args, tsubst_flags_t complain, tree in_decl)
7273 tree qualifying_scope;
7275 tree template_args = 0;
7276 bool template_id_p = false;
7278 /* A baselink indicates a function from a base class. The
7279 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7280 non-dependent types; otherwise, the lookup could not have
7281 succeeded. However, they may indicate bases of the template
7282 class, rather than the instantiated class.
7284 In addition, lookups that were not ambiguous before may be
7285 ambiguous now. Therefore, we perform the lookup again. */
7286 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7287 fns = BASELINK_FUNCTIONS (baselink);
7288 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7290 template_id_p = true;
7291 template_args = TREE_OPERAND (fns, 1);
7292 fns = TREE_OPERAND (fns, 0);
7294 template_args = tsubst_template_args (template_args, args,
7297 name = DECL_NAME (get_first_fn (fns));
7298 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7299 if (BASELINK_P (baselink) && template_id_p)
7300 BASELINK_FUNCTIONS (baselink)
7301 = build_nt (TEMPLATE_ID_EXPR,
7302 BASELINK_FUNCTIONS (baselink),
7305 object_type = current_class_type;
7306 return adjust_result_of_qualified_name_lookup (baselink,
7311 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7312 true if the qualified-id will be a postfix-expression in-and-of
7313 itself; false if more of the postfix-expression follows the
7314 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7318 tsubst_qualified_id (tree qualified_id, tree args,
7319 tsubst_flags_t complain, tree in_decl,
7320 bool done, bool address_p)
7328 my_friendly_assert (TREE_CODE (qualified_id) == SCOPE_REF, 20030706);
7330 /* Figure out what name to look up. */
7331 name = TREE_OPERAND (qualified_id, 1);
7332 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7335 template_args = TREE_OPERAND (name, 1);
7337 template_args = tsubst_template_args (template_args, args,
7339 name = TREE_OPERAND (name, 0);
7343 is_template = false;
7344 template_args = NULL_TREE;
7347 /* Substitute into the qualifying scope. When there are no ARGS, we
7348 are just trying to simplify a non-dependent expression. In that
7349 case the qualifying scope may be dependent, and, in any case,
7350 substituting will not help. */
7351 scope = TREE_OPERAND (qualified_id, 0);
7354 scope = tsubst (scope, args, complain, in_decl);
7355 expr = tsubst_copy (name, args, complain, in_decl);
7360 if (dependent_type_p (scope))
7361 return build_nt (SCOPE_REF, scope, expr);
7363 if (!BASELINK_P (name) && !DECL_P (expr))
7365 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7366 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7367 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7369 if (complain & tf_error)
7371 error ("dependent-name `%E' is parsed as a non-type, but "
7372 "instantiation yields a type", qualified_id);
7373 inform ("say `typename %E' if a type is meant", qualified_id);
7375 return error_mark_node;
7380 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7383 /* Remember that there was a reference to this entity. */
7388 expr = lookup_template_function (expr, template_args);
7390 if (expr == error_mark_node && complain & tf_error)
7391 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1));
7392 else if (TYPE_P (scope))
7394 expr = (adjust_result_of_qualified_name_lookup
7395 (expr, scope, current_class_type));
7396 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7402 /* Like tsubst, but deals with expressions. This function just replaces
7403 template parms; to finish processing the resultant expression, use
7407 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7409 enum tree_code code;
7412 if (t == NULL_TREE || t == error_mark_node)
7415 code = TREE_CODE (t);
7420 r = retrieve_local_specialization (t);
7421 my_friendly_assert (r != NULL, 20020903);
7430 if (DECL_TEMPLATE_PARM_P (t))
7431 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7432 /* There is no need to substitute into namespace-scope
7434 if (DECL_NAMESPACE_SCOPE_P (t))
7436 /* If ARGS is NULL, then T is known to be non-dependent. */
7437 if (args == NULL_TREE)
7438 return decl_constant_value (t);
7440 /* Unfortunately, we cannot just call lookup_name here.
7443 template <int I> int f() {
7445 struct S { void g() { E e = a; } };
7448 When we instantiate f<7>::S::g(), say, lookup_name is not
7449 clever enough to find f<7>::a. */
7451 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7452 /*entering_scope=*/0);
7454 for (v = TYPE_VALUES (enum_type);
7457 if (TREE_PURPOSE (v) == DECL_NAME (t))
7458 return TREE_VALUE (v);
7460 /* We didn't find the name. That should never happen; if
7461 name-lookup found it during preliminary parsing, we
7462 should find it again here during instantiation. */
7468 if (DECL_CONTEXT (t))
7472 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7473 /*entering_scope=*/1);
7474 if (ctx != DECL_CONTEXT (t))
7475 return lookup_field (ctx, DECL_NAME (t), 0, false);
7482 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7483 || local_variable_p (t))
7484 t = tsubst (t, args, complain, in_decl);
7489 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7492 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7493 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7494 args, complain, in_decl);
7495 else if (is_member_template (t))
7496 return tsubst (t, args, complain, in_decl);
7497 else if (DECL_CLASS_SCOPE_P (t)
7498 && uses_template_parms (DECL_CONTEXT (t)))
7500 /* Template template argument like the following example need
7503 template <template <class> class TT> struct C {};
7504 template <class T> struct D {
7505 template <class U> struct E {};
7510 We are processing the template argument `E' in #1 for
7511 the template instantiation #2. Originally, `E' is a
7512 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7513 have to substitute this with one having context `D<int>'. */
7515 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7516 return lookup_field (context, DECL_NAME(t), 0, false);
7519 /* Ordinary template template argument. */
7523 case REINTERPRET_CAST_EXPR:
7524 case CONST_CAST_EXPR:
7525 case STATIC_CAST_EXPR:
7526 case DYNAMIC_CAST_EXPR:
7529 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7530 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7534 case TRUTH_NOT_EXPR:
7537 case CONVERT_EXPR: /* Unary + */
7546 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7547 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7554 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7555 name = TREE_OPERAND (t, 1);
7556 if (TREE_CODE (name) == BIT_NOT_EXPR)
7558 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7560 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7562 else if (TREE_CODE (name) == SCOPE_REF
7563 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7565 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7567 name = TREE_OPERAND (name, 1);
7568 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7570 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7571 name = build_nt (SCOPE_REF, base, name);
7573 else if (TREE_CODE (name) == BASELINK)
7574 name = tsubst_baselink (name,
7575 non_reference (TREE_TYPE (object)),
7579 name = tsubst_copy (name, args, complain, in_decl);
7580 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7586 case TRUNC_DIV_EXPR:
7588 case FLOOR_DIV_EXPR:
7589 case ROUND_DIV_EXPR:
7590 case EXACT_DIV_EXPR:
7594 case TRUNC_MOD_EXPR:
7595 case FLOOR_MOD_EXPR:
7596 case TRUTH_ANDIF_EXPR:
7597 case TRUTH_ORIF_EXPR:
7598 case TRUTH_AND_EXPR:
7617 case PREDECREMENT_EXPR:
7618 case PREINCREMENT_EXPR:
7619 case POSTDECREMENT_EXPR:
7620 case POSTINCREMENT_EXPR:
7622 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7623 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7626 return build_nt (code,
7627 tsubst_copy (TREE_OPERAND (t, 0), args,
7629 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7635 case PSEUDO_DTOR_EXPR:
7638 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7639 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7640 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7647 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7648 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7649 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7650 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7657 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7658 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7659 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7660 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7664 case TEMPLATE_ID_EXPR:
7666 /* Substituted template arguments */
7667 tree fn = TREE_OPERAND (t, 0);
7668 tree targs = TREE_OPERAND (t, 1);
7670 fn = tsubst_copy (fn, args, complain, in_decl);
7672 targs = tsubst_template_args (targs, args, complain, in_decl);
7674 return lookup_template_function (fn, targs);
7679 tree purpose, value, chain;
7681 if (t == void_list_node)
7684 purpose = TREE_PURPOSE (t);
7686 purpose = tsubst_copy (purpose, args, complain, in_decl);
7687 value = TREE_VALUE (t);
7689 value = tsubst_copy (value, args, complain, in_decl);
7690 chain = TREE_CHAIN (t);
7691 if (chain && chain != void_type_node)
7692 chain = tsubst_copy (chain, args, complain, in_decl);
7693 if (purpose == TREE_PURPOSE (t)
7694 && value == TREE_VALUE (t)
7695 && chain == TREE_CHAIN (t))
7697 return tree_cons (purpose, value, chain);
7704 case TEMPLATE_TYPE_PARM:
7705 case TEMPLATE_TEMPLATE_PARM:
7706 case BOUND_TEMPLATE_TEMPLATE_PARM:
7707 case TEMPLATE_PARM_INDEX:
7709 case REFERENCE_TYPE:
7715 case UNBOUND_CLASS_TEMPLATE:
7718 return tsubst (t, args, complain, in_decl);
7720 case IDENTIFIER_NODE:
7721 if (IDENTIFIER_TYPENAME_P (t))
7723 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7724 return mangle_conv_op_name_for_type (new_type);
7731 r = build_constructor
7732 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7733 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7734 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7739 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7741 tsubst (TREE_TYPE (t), args, complain, in_decl));
7743 case CLEANUP_POINT_EXPR:
7744 /* We shouldn't have built any of these during initial template
7745 generation. Instead, they should be built during instantiation
7746 in response to the saved STMT_IS_FULL_EXPR_P setting. */
7754 /* Like tsubst_copy for expressions, etc. but also does semantic
7758 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7760 /* Live only within one (recursive) call to tsubst_expr. We use
7761 this to pass the statement expression node from the STMT_EXPR
7762 to the EXPR_STMT that is its result. */
7763 static tree cur_stmt_expr;
7767 if (t == NULL_TREE || t == error_mark_node)
7770 if (EXPR_HAS_LOCATION (t))
7771 input_location = EXPR_LOCATION (t);
7772 if (STATEMENT_CODE_P (TREE_CODE (t)))
7773 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
7775 switch (TREE_CODE (t))
7777 case STATEMENT_LIST:
7779 tree_stmt_iterator i;
7780 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
7781 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
7785 case CTOR_INITIALIZER:
7786 finish_mem_initializers (tsubst_initializer_list
7787 (TREE_OPERAND (t, 0), args));
7791 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
7792 args, complain, in_decl));
7797 tree old_stmt_expr = cur_stmt_expr;
7798 tree stmt_expr = begin_stmt_expr ();
7800 cur_stmt_expr = stmt_expr;
7801 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
7802 stmt_expr = finish_stmt_expr (stmt_expr, false);
7803 cur_stmt_expr = old_stmt_expr;
7809 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
7810 if (EXPR_STMT_STMT_EXPR_RESULT (t))
7811 finish_stmt_expr_expr (tmp, cur_stmt_expr);
7813 finish_expr_stmt (tmp);
7817 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
7818 args, complain, in_decl));
7826 decl = DECL_EXPR_DECL (t);
7827 if (TREE_CODE (decl) == LABEL_DECL)
7828 finish_label_decl (DECL_NAME (decl));
7829 else if (TREE_CODE (decl) == USING_DECL)
7831 tree scope = DECL_INITIAL (decl);
7832 tree name = DECL_NAME (decl);
7835 scope = tsubst_expr (scope, args, complain, in_decl);
7836 decl = lookup_qualified_name (scope, name,
7837 /*is_type_p=*/false,
7838 /*complain=*/false);
7839 if (decl == error_mark_node)
7840 qualified_name_lookup_error (scope, name);
7842 do_local_using_decl (decl, scope, name);
7846 init = DECL_INITIAL (decl);
7847 decl = tsubst (decl, args, complain, in_decl);
7848 if (decl != error_mark_node)
7851 DECL_INITIAL (decl) = error_mark_node;
7852 /* By marking the declaration as instantiated, we avoid
7853 trying to instantiate it. Since instantiate_decl can't
7854 handle local variables, and since we've already done
7855 all that needs to be done, that's the right thing to
7857 if (TREE_CODE (decl) == VAR_DECL)
7858 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7859 if (TREE_CODE (decl) == VAR_DECL
7860 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
7861 /* Anonymous aggregates are a special case. */
7862 finish_anon_union (decl);
7865 maybe_push_decl (decl);
7866 if (TREE_CODE (decl) == VAR_DECL
7867 && DECL_PRETTY_FUNCTION_P (decl))
7869 /* For __PRETTY_FUNCTION__ we have to adjust the
7871 const char *const name
7872 = cxx_printable_name (current_function_decl, 2);
7873 init = cp_fname_init (name, &TREE_TYPE (decl));
7876 init = tsubst_expr (init, args, complain, in_decl);
7877 cp_finish_decl (decl, init, NULL_TREE, 0);
7882 /* A DECL_EXPR can also be used as an expression, in the condition
7883 clause of an if/for/while construct. */
7888 stmt = begin_for_stmt ();
7889 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
7890 finish_for_init_stmt (stmt);
7891 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
7892 finish_for_cond (tmp, stmt);
7893 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
7894 finish_for_expr (tmp, stmt);
7895 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
7896 finish_for_stmt (stmt);
7900 stmt = begin_while_stmt ();
7901 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
7902 finish_while_stmt_cond (tmp, stmt);
7903 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
7904 finish_while_stmt (stmt);
7908 stmt = begin_do_stmt ();
7909 tsubst_expr (DO_BODY (t), args, complain, in_decl);
7910 finish_do_body (stmt);
7911 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
7912 finish_do_stmt (tmp, stmt);
7916 stmt = begin_if_stmt ();
7917 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
7918 finish_if_stmt_cond (tmp, stmt);
7919 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
7920 finish_then_clause (stmt);
7922 if (ELSE_CLAUSE (t))
7924 begin_else_clause (stmt);
7925 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
7926 finish_else_clause (stmt);
7929 finish_if_stmt (stmt);
7933 if (BIND_EXPR_BODY_BLOCK (t))
7934 stmt = begin_function_body ();
7936 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
7937 ? BCS_TRY_BLOCK : 0);
7939 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
7941 if (BIND_EXPR_BODY_BLOCK (t))
7942 finish_function_body (stmt);
7944 finish_compound_stmt (stmt);
7948 finish_break_stmt ();
7952 finish_continue_stmt ();
7956 stmt = begin_switch_stmt ();
7957 tmp = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
7958 finish_switch_cond (tmp, stmt);
7959 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
7960 finish_switch_stmt (stmt);
7963 case CASE_LABEL_EXPR:
7964 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
7965 tsubst_expr (CASE_HIGH (t), args, complain,
7970 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
7974 tmp = GOTO_DESTINATION (t);
7975 if (TREE_CODE (tmp) != LABEL_DECL)
7976 /* Computed goto's must be tsubst'd into. On the other hand,
7977 non-computed gotos must not be; the identifier in question
7978 will have no binding. */
7979 tmp = tsubst_expr (tmp, args, complain, in_decl);
7981 tmp = DECL_NAME (tmp);
7982 finish_goto_stmt (tmp);
7986 tmp = finish_asm_stmt
7987 (ASM_VOLATILE_P (t),
7988 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
7989 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
7990 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
7991 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
7992 ASM_INPUT_P (tmp) = ASM_INPUT_P (t);
7998 stmt = begin_try_block ();
7999 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8000 finish_cleanup_try_block (stmt);
8001 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8007 if (FN_TRY_BLOCK_P (t))
8008 stmt = begin_function_try_block ();
8010 stmt = begin_try_block ();
8012 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8014 if (FN_TRY_BLOCK_P (t))
8015 finish_function_try_block (stmt);
8017 finish_try_block (stmt);
8019 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8020 if (FN_TRY_BLOCK_P (t))
8021 finish_function_handler_sequence (stmt);
8023 finish_handler_sequence (stmt);
8031 stmt = begin_handler ();
8032 if (HANDLER_PARMS (t))
8034 decl = HANDLER_PARMS (t);
8035 decl = tsubst (decl, args, complain, in_decl);
8036 /* Prevent instantiate_decl from trying to instantiate
8037 this variable. We've already done all that needs to be
8039 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8043 finish_handler_parms (decl, stmt);
8044 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8045 finish_handler (stmt);
8050 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8054 if (!STATEMENT_CODE_P (TREE_CODE (t)))
8055 return tsubst_copy_and_build (t, args, complain, in_decl,
8056 /*function_p=*/false);
8063 /* T is a postfix-expression that is not being used in a function
8064 call. Return the substituted version of T. */
8067 tsubst_non_call_postfix_expression (tree t, tree args,
8068 tsubst_flags_t complain,
8071 if (TREE_CODE (t) == SCOPE_REF)
8072 t = tsubst_qualified_id (t, args, complain, in_decl,
8073 /*done=*/false, /*address_p=*/false);
8075 t = tsubst_copy_and_build (t, args, complain, in_decl,
8076 /*function_p=*/false);
8081 /* Like tsubst but deals with expressions and performs semantic
8082 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8085 tsubst_copy_and_build (tree t,
8087 tsubst_flags_t complain,
8091 #define RECUR(NODE) \
8092 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8096 if (t == NULL_TREE || t == error_mark_node)
8099 switch (TREE_CODE (t))
8104 case IDENTIFIER_NODE:
8108 tree qualifying_class;
8109 bool non_integral_constant_expression_p;
8110 const char *error_msg;
8112 if (IDENTIFIER_TYPENAME_P (t))
8114 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8115 t = mangle_conv_op_name_for_type (new_type);
8118 /* Look up the name. */
8119 decl = lookup_name (t, 0);
8121 /* By convention, expressions use ERROR_MARK_NODE to indicate
8122 failure, not NULL_TREE. */
8123 if (decl == NULL_TREE)
8124 decl = error_mark_node;
8126 decl = finish_id_expression (t, decl, NULL_TREE,
8129 /*integral_constant_expression_p=*/false,
8130 /*allow_non_integral_constant_expression_p=*/false,
8131 &non_integral_constant_expression_p,
8135 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8136 decl = unqualified_name_lookup_error (decl);
8140 case TEMPLATE_ID_EXPR:
8143 tree template = RECUR (TREE_OPERAND (t, 0));
8144 tree targs = TREE_OPERAND (t, 1);
8147 targs = tsubst_template_args (targs, args, complain, in_decl);
8149 if (TREE_CODE (template) == COMPONENT_REF)
8151 object = TREE_OPERAND (template, 0);
8152 template = TREE_OPERAND (template, 1);
8156 template = lookup_template_function (template, targs);
8159 return build (COMPONENT_REF, TREE_TYPE (template),
8160 object, template, NULL_TREE);
8166 return build_x_indirect_ref (RECUR (TREE_OPERAND (t, 0)), "unary *");
8170 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8171 RECUR (TREE_OPERAND (t, 0)));
8174 return build_functional_cast
8175 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8176 RECUR (TREE_OPERAND (t, 0)));
8178 case REINTERPRET_CAST_EXPR:
8179 return build_reinterpret_cast
8180 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8181 RECUR (TREE_OPERAND (t, 0)));
8183 case CONST_CAST_EXPR:
8184 return build_const_cast
8185 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8186 RECUR (TREE_OPERAND (t, 0)));
8188 case DYNAMIC_CAST_EXPR:
8189 return build_dynamic_cast
8190 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8191 RECUR (TREE_OPERAND (t, 0)));
8193 case STATIC_CAST_EXPR:
8194 return build_static_cast
8195 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8196 RECUR (TREE_OPERAND (t, 0)));
8198 case POSTDECREMENT_EXPR:
8199 case POSTINCREMENT_EXPR:
8200 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8201 args, complain, in_decl);
8202 return build_x_unary_op (TREE_CODE (t), op1);
8204 case PREDECREMENT_EXPR:
8205 case PREINCREMENT_EXPR:
8209 case TRUTH_NOT_EXPR:
8210 case CONVERT_EXPR: /* Unary + */
8213 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8216 op1 = TREE_OPERAND (t, 0);
8217 if (TREE_CODE (op1) == SCOPE_REF)
8218 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8219 /*done=*/true, /*address_p=*/true);
8221 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8223 if (TREE_CODE (op1) == LABEL_DECL)
8224 return finish_label_address_expr (DECL_NAME (op1));
8225 return build_x_unary_op (ADDR_EXPR, op1);
8230 case TRUNC_DIV_EXPR:
8232 case FLOOR_DIV_EXPR:
8233 case ROUND_DIV_EXPR:
8234 case EXACT_DIV_EXPR:
8238 case TRUNC_MOD_EXPR:
8239 case FLOOR_MOD_EXPR:
8240 case TRUTH_ANDIF_EXPR:
8241 case TRUTH_ORIF_EXPR:
8242 case TRUTH_AND_EXPR:
8258 return build_x_binary_op
8260 RECUR (TREE_OPERAND (t, 0)),
8261 RECUR (TREE_OPERAND (t, 1)),
8262 /*overloaded_p=*/NULL);
8265 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8266 /*address_p=*/false);
8269 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8272 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)),
8273 NULL_TREE, NULL_TREE);
8275 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8276 args, complain, in_decl);
8277 /* Remember that there was a reference to this entity. */
8280 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8284 op1 = TREE_OPERAND (t, 0);
8287 /* When there are no ARGS, we are trying to evaluate a
8288 non-dependent expression from the parser. Trying to do
8289 the substitutions may not work. */
8291 op1 = TREE_TYPE (op1);
8300 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8302 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8305 return build_x_modify_expr
8306 (RECUR (TREE_OPERAND (t, 0)),
8307 TREE_CODE (TREE_OPERAND (t, 1)),
8308 RECUR (TREE_OPERAND (t, 2)));
8311 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8312 args, complain, in_decl);
8313 /* Remember that there was a reference to this entity. */
8316 return build_x_arrow (op1);
8320 (RECUR (TREE_OPERAND (t, 0)),
8321 RECUR (TREE_OPERAND (t, 1)),
8322 RECUR (TREE_OPERAND (t, 2)),
8323 RECUR (TREE_OPERAND (t, 3)),
8324 NEW_EXPR_USE_GLOBAL (t));
8327 return delete_sanity
8328 (RECUR (TREE_OPERAND (t, 0)),
8329 RECUR (TREE_OPERAND (t, 1)),
8330 DELETE_EXPR_USE_VEC (t),
8331 DELETE_EXPR_USE_GLOBAL (t));
8334 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8335 RECUR (TREE_OPERAND (t, 1)));
8344 function = TREE_OPERAND (t, 0);
8345 /* When we parsed the expression, we determined whether or
8346 not Koenig lookup should be performed. */
8347 koenig_p = KOENIG_LOOKUP_P (t);
8348 if (TREE_CODE (function) == SCOPE_REF)
8351 function = tsubst_qualified_id (function, args, complain, in_decl,
8353 /*address_p=*/false);
8357 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8358 && (TREE_CODE (TREE_OPERAND (function, 1))
8360 function = tsubst_copy_and_build (function, args, complain,
8363 if (BASELINK_P (function))
8367 call_args = RECUR (TREE_OPERAND (t, 1));
8369 /* We do not perform argument-dependent lookup if normal
8370 lookup finds a non-function, in accordance with the
8371 expected resolution of DR 218. */
8373 && (is_overloaded_fn (function)
8374 || TREE_CODE (function) == IDENTIFIER_NODE))
8375 function = perform_koenig_lookup (function, call_args);
8377 if (TREE_CODE (function) == IDENTIFIER_NODE)
8379 unqualified_name_lookup_error (function);
8380 return error_mark_node;
8383 /* Remember that there was a reference to this entity. */
8384 if (DECL_P (function))
8385 mark_used (function);
8387 function = convert_from_reference (function);
8389 if (TREE_CODE (function) == OFFSET_REF)
8390 return build_offset_ref_call_from_tree (function, call_args);
8391 if (TREE_CODE (function) == COMPONENT_REF)
8393 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8394 return finish_call_expr (function, call_args,
8395 /*disallow_virtual=*/false,
8396 /*koenig_p=*/false);
8398 return (build_new_method_call
8399 (TREE_OPERAND (function, 0),
8400 TREE_OPERAND (function, 1),
8401 call_args, NULL_TREE,
8402 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8404 return finish_call_expr (function, call_args,
8405 /*disallow_virtual=*/qualified_p,
8410 return build_x_conditional_expr
8411 (RECUR (TREE_OPERAND (t, 0)),
8412 RECUR (TREE_OPERAND (t, 1)),
8413 RECUR (TREE_OPERAND (t, 2)));
8415 case PSEUDO_DTOR_EXPR:
8416 return finish_pseudo_destructor_expr
8417 (RECUR (TREE_OPERAND (t, 0)),
8418 RECUR (TREE_OPERAND (t, 1)),
8419 RECUR (TREE_OPERAND (t, 2)));
8423 tree purpose, value, chain;
8425 if (t == void_list_node)
8428 purpose = TREE_PURPOSE (t);
8430 purpose = RECUR (purpose);
8431 value = TREE_VALUE (t);
8433 value = RECUR (value);
8434 chain = TREE_CHAIN (t);
8435 if (chain && chain != void_type_node)
8436 chain = RECUR (chain);
8437 if (purpose == TREE_PURPOSE (t)
8438 && value == TREE_VALUE (t)
8439 && chain == TREE_CHAIN (t))
8441 return tree_cons (purpose, value, chain);
8449 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8450 args, complain, in_decl);
8451 /* Remember that there was a reference to this entity. */
8452 if (DECL_P (object))
8455 member = TREE_OPERAND (t, 1);
8456 if (BASELINK_P (member))
8457 member = tsubst_baselink (member,
8458 non_reference (TREE_TYPE (object)),
8459 args, complain, in_decl);
8461 member = tsubst_copy (member, args, complain, in_decl);
8463 if (!CLASS_TYPE_P (TREE_TYPE (object)))
8465 if (TREE_CODE (member) == BIT_NOT_EXPR)
8466 return finish_pseudo_destructor_expr (object,
8468 TREE_TYPE (object));
8469 else if (TREE_CODE (member) == SCOPE_REF
8470 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8471 return finish_pseudo_destructor_expr (object,
8473 TREE_TYPE (object));
8475 else if (TREE_CODE (member) == SCOPE_REF
8476 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8481 /* Lookup the template functions now that we know what the
8483 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8484 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8485 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8486 /*is_type_p=*/false,
8487 /*complain=*/false);
8488 if (BASELINK_P (member))
8489 BASELINK_FUNCTIONS (member)
8490 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8494 qualified_name_lookup_error (TREE_TYPE (object), tmpl);
8495 return error_mark_node;
8498 else if (TREE_CODE (member) == FIELD_DECL)
8499 return finish_non_static_data_member (member, object, NULL_TREE);
8501 return finish_class_member_access_expr (object, member);
8506 (RECUR (TREE_OPERAND (t, 0)));
8512 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8515 /* digest_init will do the wrong thing if we let it. */
8516 if (type && TYPE_PTRMEMFUNC_P (type))
8520 /* We do not want to process the purpose of aggregate
8521 initializers as they are identifier nodes which will be
8522 looked up by digest_init. */
8523 purpose_p = !(type && IS_AGGR_TYPE (type));
8524 for (elts = CONSTRUCTOR_ELTS (t);
8526 elts = TREE_CHAIN (elts))
8528 tree purpose = TREE_PURPOSE (elts);
8529 tree value = TREE_VALUE (elts);
8531 if (purpose && purpose_p)
8532 purpose = RECUR (purpose);
8533 value = RECUR (value);
8534 r = tree_cons (purpose, value, r);
8537 r = build_constructor (NULL_TREE, nreverse (r));
8538 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8541 return digest_init (type, r, 0);
8547 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8548 if (TYPE_P (operand_0))
8549 return get_typeid (operand_0);
8550 return build_typeid (operand_0);
8554 return convert_from_reference (tsubst_copy (t, args, complain, in_decl));
8558 t = tsubst_copy (t, args, complain, in_decl);
8559 return convert_from_reference (t);
8562 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8563 tsubst_copy (TREE_TYPE (t), args, complain,
8567 return tsubst_copy (t, args, complain, in_decl);
8573 /* Verify that the instantiated ARGS are valid. For type arguments,
8574 make sure that the type's linkage is ok. For non-type arguments,
8575 make sure they are constants if they are integral or enumerations.
8576 Emit an error under control of COMPLAIN, and return TRUE on error. */
8579 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8581 int ix, len = DECL_NTPARMS (tmpl);
8582 bool result = false;
8584 for (ix = 0; ix != len; ix++)
8586 tree t = TREE_VEC_ELT (args, ix);
8590 /* [basic.link]: A name with no linkage (notably, the name
8591 of a class or enumeration declared in a local scope)
8592 shall not be used to declare an entity with linkage.
8593 This implies that names with no linkage cannot be used as
8594 template arguments. */
8595 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8599 if (!(complain & tf_error))
8601 else if (TYPE_ANONYMOUS_P (nt))
8602 error ("`%T' uses anonymous type", t);
8604 error ("`%T' uses local type `%T'", t, nt);
8607 /* In order to avoid all sorts of complications, we do not
8608 allow variably-modified types as template arguments. */
8609 else if (variably_modified_type_p (t, NULL_TREE))
8611 if (complain & tf_error)
8612 error ("`%T' is a variably modified type", t);
8616 /* A non-type argument of integral or enumerated type must be a
8618 else if (TREE_TYPE (t)
8619 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8620 && !TREE_CONSTANT (t))
8622 if (complain & tf_error)
8623 error ("integral expression `%E' is not constant", t);
8627 if (result && complain & tf_error)
8628 error (" trying to instantiate `%D'", tmpl);
8632 /* Instantiate the indicated variable or function template TMPL with
8633 the template arguments in TARG_PTR. */
8636 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8642 if (tmpl == error_mark_node)
8643 return error_mark_node;
8645 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 283);
8647 /* If this function is a clone, handle it specially. */
8648 if (DECL_CLONED_FUNCTION_P (tmpl))
8653 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8655 if (spec == error_mark_node)
8656 return error_mark_node;
8658 /* Look for the clone. */
8659 FOR_EACH_CLONE (clone, spec)
8660 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8662 /* We should always have found the clone by now. */
8667 /* Check to see if we already have this specialization. */
8668 spec = retrieve_specialization (tmpl, targ_ptr);
8669 if (spec != NULL_TREE)
8672 gen_tmpl = most_general_template (tmpl);
8673 if (tmpl != gen_tmpl)
8675 /* The TMPL is a partial instantiation. To get a full set of
8676 arguments we must add the arguments used to perform the
8677 partial instantiation. */
8678 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
8681 /* Check to see if we already have this specialization. */
8682 spec = retrieve_specialization (gen_tmpl, targ_ptr);
8683 if (spec != NULL_TREE)
8687 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
8689 return error_mark_node;
8691 /* We are building a FUNCTION_DECL, during which the access of its
8692 parameters and return types have to be checked. However this
8693 FUNCTION_DECL which is the desired context for access checking
8694 is not built yet. We solve this chicken-and-egg problem by
8695 deferring all checks until we have the FUNCTION_DECL. */
8696 push_deferring_access_checks (dk_deferred);
8698 /* Substitute template parameters. */
8699 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
8700 targ_ptr, complain, gen_tmpl);
8702 /* Now we know the specialization, compute access previously
8704 push_access_scope (fndecl);
8705 perform_deferred_access_checks ();
8706 pop_access_scope (fndecl);
8707 pop_deferring_access_checks ();
8709 /* The DECL_TI_TEMPLATE should always be the immediate parent
8710 template, not the most general template. */
8711 DECL_TI_TEMPLATE (fndecl) = tmpl;
8713 /* If we've just instantiated the main entry point for a function,
8714 instantiate all the alternate entry points as well. We do this
8715 by cloning the instantiation of the main entry point, not by
8716 instantiating the template clones. */
8717 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
8718 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
8723 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8724 arguments that are being used when calling it. TARGS is a vector
8725 into which the deduced template arguments are placed.
8727 Return zero for success, 2 for an incomplete match that doesn't resolve
8728 all the types, and 1 for complete failure. An error message will be
8729 printed only for an incomplete match.
8731 If FN is a conversion operator, or we are trying to produce a specific
8732 specialization, RETURN_TYPE is the return type desired.
8734 The EXPLICIT_TARGS are explicit template arguments provided via a
8737 The parameter STRICT is one of:
8740 We are deducing arguments for a function call, as in
8744 We are deducing arguments for a conversion function, as in
8748 We are deducing arguments when doing an explicit instantiation
8749 as in [temp.explicit], when determining an explicit specialization
8750 as in [temp.expl.spec], or when taking the address of a function
8751 template, as in [temp.deduct.funcaddr].
8754 We are deducing arguments when calculating the partial
8755 ordering between specializations of function or class
8756 templates, as in [temp.func.order] and [temp.class.order].
8758 LEN is the number of parms to consider before returning success, or -1
8759 for all. This is used in partial ordering to avoid comparing parms for
8760 which no actual argument was passed, since they are not considered in
8761 overload resolution (and are explicitly excluded from consideration in
8762 partial ordering in [temp.func.order]/6). */
8765 fn_type_unification (tree fn,
8766 tree explicit_targs,
8770 unification_kind_t strict,
8777 my_friendly_assert (TREE_CODE (fn) == TEMPLATE_DECL, 0);
8779 fntype = TREE_TYPE (fn);
8784 The specified template arguments must match the template
8785 parameters in kind (i.e., type, nontype, template), and there
8786 must not be more arguments than there are parameters;
8787 otherwise type deduction fails.
8789 Nontype arguments must match the types of the corresponding
8790 nontype template parameters, or must be convertible to the
8791 types of the corresponding nontype parameters as specified in
8792 _temp.arg.nontype_, otherwise type deduction fails.
8794 All references in the function type of the function template
8795 to the corresponding template parameters are replaced by the
8796 specified template argument values. If a substitution in a
8797 template parameter or in the function type of the function
8798 template results in an invalid type, type deduction fails. */
8800 tree converted_args;
8804 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8805 explicit_targs, NULL_TREE, tf_none,
8806 /*require_all_arguments=*/0));
8807 if (converted_args == error_mark_node)
8810 /* Substitute the explicit args into the function type. This is
8811 necessary so that, for instance, explicitly declared function
8812 arguments can match null pointed constants. If we were given
8813 an incomplete set of explicit args, we must not do semantic
8814 processing during substitution as we could create partial
8816 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
8817 processing_template_decl += incomplete;
8818 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
8819 processing_template_decl -= incomplete;
8821 if (fntype == error_mark_node)
8824 /* Place the explicitly specified arguments in TARGS. */
8825 for (i = NUM_TMPL_ARGS (converted_args); i--;)
8826 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
8829 parms = TYPE_ARG_TYPES (fntype);
8830 /* Never do unification on the 'this' parameter. */
8831 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
8832 parms = TREE_CHAIN (parms);
8836 /* We've been given a return type to match, prepend it. */
8837 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
8838 args = tree_cons (NULL_TREE, return_type, args);
8843 /* We allow incomplete unification without an error message here
8844 because the standard doesn't seem to explicitly prohibit it. Our
8845 callers must be ready to deal with unification failures in any
8847 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8848 targs, parms, args, /*subr=*/0,
8849 strict, /*allow_incomplete*/1, len);
8852 /* All is well so far. Now, check:
8856 When all template arguments have been deduced, all uses of
8857 template parameters in nondeduced contexts are replaced with
8858 the corresponding deduced argument values. If the
8859 substitution results in an invalid type, as described above,
8860 type deduction fails. */
8861 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
8868 /* Adjust types before performing type deduction, as described in
8869 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
8870 sections are symmetric. PARM is the type of a function parameter
8871 or the return type of the conversion function. ARG is the type of
8872 the argument passed to the call, or the type of the value
8873 initialized with the result of the conversion function. */
8876 maybe_adjust_types_for_deduction (unification_kind_t strict,
8889 /* Swap PARM and ARG throughout the remainder of this
8890 function; the handling is precisely symmetric since PARM
8891 will initialize ARG rather than vice versa. */
8899 /* There is nothing to do in this case. */
8903 /* DR 214. [temp.func.order] is underspecified, and leads to no
8904 ordering between things like `T *' and `T const &' for `U *'.
8905 The former has T=U and the latter T=U*. The former looks more
8906 specialized and John Spicer considers it well-formed (the EDG
8907 compiler accepts it).
8909 John also confirms that deduction should proceed as in a function
8910 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
8911 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
8912 to an actual call can have such a type.
8914 If both ARG and PARM are REFERENCE_TYPE, we change neither.
8915 If only ARG is a REFERENCE_TYPE, we look through that and then
8916 proceed as with DEDUCE_CALL (which could further convert it). */
8917 if (TREE_CODE (*arg) == REFERENCE_TYPE)
8919 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8921 *arg = TREE_TYPE (*arg);
8928 if (TREE_CODE (*parm) != REFERENCE_TYPE)
8930 /* [temp.deduct.call]
8932 If P is not a reference type:
8934 --If A is an array type, the pointer type produced by the
8935 array-to-pointer standard conversion (_conv.array_) is
8936 used in place of A for type deduction; otherwise,
8938 --If A is a function type, the pointer type produced by
8939 the function-to-pointer standard conversion
8940 (_conv.func_) is used in place of A for type deduction;
8943 --If A is a cv-qualified type, the top level
8944 cv-qualifiers of A's type are ignored for type
8946 if (TREE_CODE (*arg) == ARRAY_TYPE)
8947 *arg = build_pointer_type (TREE_TYPE (*arg));
8948 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
8949 *arg = build_pointer_type (*arg);
8951 *arg = TYPE_MAIN_VARIANT (*arg);
8954 /* [temp.deduct.call]
8956 If P is a cv-qualified type, the top level cv-qualifiers
8957 of P's type are ignored for type deduction. If P is a
8958 reference type, the type referred to by P is used for
8960 *parm = TYPE_MAIN_VARIANT (*parm);
8961 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8963 *parm = TREE_TYPE (*parm);
8964 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
8967 /* DR 322. For conversion deduction, remove a reference type on parm
8968 too (which has been swapped into ARG). */
8969 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
8970 *arg = TREE_TYPE (*arg);
8975 /* Most parms like fn_type_unification.
8977 If SUBR is 1, we're being called recursively (to unify the
8978 arguments of a function or method parameter of a function
8982 type_unification_real (tree tparms,
8987 unification_kind_t strict,
8988 int allow_incomplete,
8993 int ntparms = TREE_VEC_LENGTH (tparms);
8995 int saw_undeduced = 0;
8999 my_friendly_assert (TREE_CODE (tparms) == TREE_VEC, 289);
9000 my_friendly_assert (xparms == NULL_TREE
9001 || TREE_CODE (xparms) == TREE_LIST, 290);
9002 my_friendly_assert (!xargs || TREE_CODE (xargs) == TREE_LIST, 291);
9003 my_friendly_assert (ntparms > 0, 292);
9008 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9009 | UNIFY_ALLOW_DERIVED);
9013 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9017 sub_strict = UNIFY_ALLOW_NONE;
9021 sub_strict = UNIFY_ALLOW_NONE;
9037 && parms != void_list_node
9039 && args != void_list_node)
9041 parm = TREE_VALUE (parms);
9042 parms = TREE_CHAIN (parms);
9043 arg = TREE_VALUE (args);
9044 args = TREE_CHAIN (args);
9046 if (arg == error_mark_node)
9048 if (arg == unknown_type_node)
9049 /* We can't deduce anything from this, but we might get all the
9050 template args from other function args. */
9053 /* Conversions will be performed on a function argument that
9054 corresponds with a function parameter that contains only
9055 non-deducible template parameters and explicitly specified
9056 template parameters. */
9057 if (!uses_template_parms (parm))
9062 type = TREE_TYPE (arg);
9066 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
9068 if (same_type_p (parm, type))
9072 /* It might work; we shouldn't check now, because we might
9073 get into infinite recursion. Overload resolution will
9082 my_friendly_assert (TREE_TYPE (arg) != NULL_TREE, 293);
9083 if (type_unknown_p (arg))
9085 /* [temp.deduct.type] A template-argument can be deduced from
9086 a pointer to function or pointer to member function
9087 argument if the set of overloaded functions does not
9088 contain function templates and at most one of a set of
9089 overloaded functions provides a unique match. */
9091 if (resolve_overloaded_unification
9092 (tparms, targs, parm, arg, strict, sub_strict)
9097 arg = TREE_TYPE (arg);
9098 if (arg == error_mark_node)
9103 int arg_strict = sub_strict;
9106 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9108 if (unify (tparms, targs, parm, arg, arg_strict))
9112 /* Are we done with the interesting parms? */
9116 /* Fail if we've reached the end of the parm list, and more args
9117 are present, and the parm list isn't variadic. */
9118 if (args && args != void_list_node && parms == void_list_node)
9120 /* Fail if parms are left and they don't have default values. */
9122 && parms != void_list_node
9123 && TREE_PURPOSE (parms) == NULL_TREE)
9128 for (i = 0; i < ntparms; i++)
9129 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
9131 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9133 /* If this is an undeduced nontype parameter that depends on
9134 a type parameter, try another pass; its type may have been
9135 deduced from a later argument than the one from which
9136 this parameter can be deduced. */
9137 if (TREE_CODE (tparm) == PARM_DECL
9138 && uses_template_parms (TREE_TYPE (tparm))
9139 && !saw_undeduced++)
9142 if (!allow_incomplete)
9143 error ("incomplete type unification");
9149 /* Subroutine of type_unification_real. Args are like the variables at the
9150 call site. ARG is an overloaded function (or template-id); we try
9151 deducing template args from each of the overloads, and if only one
9152 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9155 resolve_overloaded_unification (tree tparms,
9159 unification_kind_t strict,
9162 tree tempargs = copy_node (targs);
9166 if (TREE_CODE (arg) == ADDR_EXPR)
9168 arg = TREE_OPERAND (arg, 0);
9174 if (TREE_CODE (arg) == COMPONENT_REF)
9175 /* Handle `&x' where `x' is some static or non-static member
9177 arg = TREE_OPERAND (arg, 1);
9179 if (TREE_CODE (arg) == OFFSET_REF)
9180 arg = TREE_OPERAND (arg, 1);
9182 /* Strip baselink information. */
9183 if (BASELINK_P (arg))
9184 arg = BASELINK_FUNCTIONS (arg);
9186 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9188 /* If we got some explicit template args, we need to plug them into
9189 the affected templates before we try to unify, in case the
9190 explicit args will completely resolve the templates in question. */
9192 tree expl_subargs = TREE_OPERAND (arg, 1);
9193 arg = TREE_OPERAND (arg, 0);
9195 for (; arg; arg = OVL_NEXT (arg))
9197 tree fn = OVL_CURRENT (arg);
9200 if (TREE_CODE (fn) != TEMPLATE_DECL)
9203 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
9207 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9208 good += try_one_overload (tparms, targs, tempargs, parm,
9209 elem, strict, sub_strict, addr_p);
9213 else if (TREE_CODE (arg) == OVERLOAD
9214 || TREE_CODE (arg) == FUNCTION_DECL)
9216 for (; arg; arg = OVL_NEXT (arg))
9217 good += try_one_overload (tparms, targs, tempargs, parm,
9218 TREE_TYPE (OVL_CURRENT (arg)),
9219 strict, sub_strict, addr_p);
9224 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9225 to function or pointer to member function argument if the set of
9226 overloaded functions does not contain function templates and at most
9227 one of a set of overloaded functions provides a unique match.
9229 So if we found multiple possibilities, we return success but don't
9234 int i = TREE_VEC_LENGTH (targs);
9236 if (TREE_VEC_ELT (tempargs, i))
9237 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9245 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9246 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9247 different overloads deduce different arguments for a given parm.
9248 ADDR_P is true if the expression for which deduction is being
9249 performed was of the form "& fn" rather than simply "fn".
9251 Returns 1 on success. */
9254 try_one_overload (tree tparms,
9259 unification_kind_t strict,
9267 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9268 to function or pointer to member function argument if the set of
9269 overloaded functions does not contain function templates and at most
9270 one of a set of overloaded functions provides a unique match.
9272 So if this is a template, just return success. */
9274 if (uses_template_parms (arg))
9277 if (TREE_CODE (arg) == METHOD_TYPE)
9278 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9280 arg = build_pointer_type (arg);
9282 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9284 /* We don't copy orig_targs for this because if we have already deduced
9285 some template args from previous args, unify would complain when we
9286 try to deduce a template parameter for the same argument, even though
9287 there isn't really a conflict. */
9288 nargs = TREE_VEC_LENGTH (targs);
9289 tempargs = make_tree_vec (nargs);
9291 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9294 /* First make sure we didn't deduce anything that conflicts with
9295 explicitly specified args. */
9296 for (i = nargs; i--; )
9298 tree elt = TREE_VEC_ELT (tempargs, i);
9299 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9301 if (elt == NULL_TREE)
9303 else if (uses_template_parms (elt))
9305 /* Since we're unifying against ourselves, we will fill in template
9306 args used in the function parm list with our own template parms.
9308 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9311 else if (oldelt && ! template_args_equal (oldelt, elt))
9315 for (i = nargs; i--; )
9317 tree elt = TREE_VEC_ELT (tempargs, i);
9320 TREE_VEC_ELT (targs, i) = elt;
9326 /* Verify that nondeduce template argument agrees with the type
9327 obtained from argument deduction. Return nonzero if the
9332 struct A { typedef int X; };
9333 template <class T, class U> struct C {};
9334 template <class T> struct C<T, typename T::X> {};
9336 Then with the instantiation `C<A, int>', we can deduce that
9337 `T' is `A' but unify () does not check whether `typename T::X'
9338 is `int'. This function ensure that they agree.
9340 TARGS, PARMS are the same as the arguments of unify.
9341 ARGS contains template arguments from all levels. */
9344 verify_class_unification (tree targs, tree parms, tree args)
9346 parms = tsubst (parms, add_outermost_template_args (args, targs),
9347 tf_none, NULL_TREE);
9348 if (parms == error_mark_node)
9351 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9354 /* PARM is a template class (perhaps with unbound template
9355 parameters). ARG is a fully instantiated type. If ARG can be
9356 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9357 TARGS are as for unify. */
9360 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9364 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9365 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9366 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9369 /* We need to make a new template argument vector for the call to
9370 unify. If we used TARGS, we'd clutter it up with the result of
9371 the attempted unification, even if this class didn't work out.
9372 We also don't want to commit ourselves to all the unifications
9373 we've already done, since unification is supposed to be done on
9374 an argument-by-argument basis. In other words, consider the
9375 following pathological case:
9377 template <int I, int J, int K>
9380 template <int I, int J>
9381 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9383 template <int I, int J, int K>
9384 void f(S<I, J, K>, S<I, I, I>);
9393 Now, by the time we consider the unification involving `s2', we
9394 already know that we must have `f<0, 0, 0>'. But, even though
9395 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9396 because there are two ways to unify base classes of S<0, 1, 2>
9397 with S<I, I, I>. If we kept the already deduced knowledge, we
9398 would reject the possibility I=1. */
9399 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9401 /* If unification failed, we're done. */
9402 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9403 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9409 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
9410 have already discovered to be satisfactory. ARG_BINFO is the binfo
9411 for the base class of ARG that we are currently examining. */
9414 get_template_base_recursive (tree tparms,
9423 tree arg = BINFO_TYPE (arg_binfo);
9425 if (!(flags & GTB_IGNORE_TYPE))
9427 tree r = try_class_unification (tparms, targs,
9430 /* If there is more than one satisfactory baseclass, then:
9434 If they yield more than one possible deduced A, the type
9438 if (r && rval && !same_type_p (r, rval))
9439 return error_mark_node;
9444 /* Process base types. */
9445 for (i = 0; BINFO_BASE_ITERATE (arg_binfo, i, base_binfo); i++)
9449 /* Skip this base, if we've already seen it. */
9450 if (BINFO_MARKED (base_binfo))
9454 (flags & GTB_VIA_VIRTUAL) || BINFO_VIRTUAL_P (base_binfo);
9456 /* When searching for a non-virtual, we cannot mark virtually
9459 BINFO_MARKED (base_binfo) = 1;
9461 rval = get_template_base_recursive (tparms, targs,
9465 GTB_VIA_VIRTUAL * this_virtual);
9467 /* If we discovered more than one matching base class, we can
9469 if (rval == error_mark_node)
9470 return error_mark_node;
9476 /* Given a template type PARM and a class type ARG, find the unique
9477 base type in ARG that is an instance of PARM. We do not examine
9478 ARG itself; only its base-classes. If there is no appropriate base
9479 class, return NULL_TREE. If there is more than one, return
9480 error_mark_node. PARM may be the type of a partial specialization,
9481 as well as a plain template type. Used by unify. */
9484 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9489 my_friendly_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)), 92);
9491 arg_binfo = TYPE_BINFO (complete_type (arg));
9493 /* The type could not be completed. */
9496 rval = get_template_base_recursive (tparms, targs,
9501 /* Since get_template_base_recursive marks the bases classes, we
9502 must unmark them here. */
9503 dfs_walk (arg_binfo, dfs_unmark, markedp, 0);
9508 /* Returns the level of DECL, which declares a template parameter. */
9511 template_decl_level (tree decl)
9513 switch (TREE_CODE (decl))
9517 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9520 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9528 /* Decide whether ARG can be unified with PARM, considering only the
9529 cv-qualifiers of each type, given STRICT as documented for unify.
9530 Returns nonzero iff the unification is OK on that basis. */
9533 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9535 int arg_quals = cp_type_quals (arg);
9536 int parm_quals = cp_type_quals (parm);
9538 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9539 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9541 /* Although a CVR qualifier is ignored when being applied to a
9542 substituted template parameter ([8.3.2]/1 for example), that
9543 does not apply during deduction [14.8.2.4]/1, (even though
9544 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9545 this). Except when we're allowing additional CV qualifiers
9546 at the outer level [14.8.2.1]/3,1st bullet. */
9547 if ((TREE_CODE (arg) == REFERENCE_TYPE
9548 || TREE_CODE (arg) == FUNCTION_TYPE
9549 || TREE_CODE (arg) == METHOD_TYPE)
9550 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9553 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9554 && (parm_quals & TYPE_QUAL_RESTRICT))
9558 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9559 && (arg_quals & parm_quals) != parm_quals)
9562 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9563 && (parm_quals & arg_quals) != arg_quals)
9569 /* Takes parameters as for type_unification. Returns 0 if the
9570 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9571 bitwise or of the following flags:
9574 Require an exact match between PARM and ARG.
9575 UNIFY_ALLOW_MORE_CV_QUAL:
9576 Allow the deduced ARG to be more cv-qualified (by qualification
9577 conversion) than ARG.
9578 UNIFY_ALLOW_LESS_CV_QUAL:
9579 Allow the deduced ARG to be less cv-qualified than ARG.
9580 UNIFY_ALLOW_DERIVED:
9581 Allow the deduced ARG to be a template base class of ARG,
9582 or a pointer to a template base class of the type pointed to by
9584 UNIFY_ALLOW_INTEGER:
9585 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9586 case for more information.
9587 UNIFY_ALLOW_OUTER_LEVEL:
9588 This is the outermost level of a deduction. Used to determine validity
9589 of qualification conversions. A valid qualification conversion must
9590 have const qualified pointers leading up to the inner type which
9591 requires additional CV quals, except at the outer level, where const
9592 is not required [conv.qual]. It would be normal to set this flag in
9593 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9594 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9595 This is the outermost level of a deduction, and PARM can be more CV
9596 qualified at this point.
9597 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9598 This is the outermost level of a deduction, and PARM can be less CV
9599 qualified at this point.
9600 UNIFY_ALLOW_MAX_CORRECTION:
9601 This is an INTEGER_TYPE's maximum value. Used if the range may
9602 have been derived from a size specification, such as an array size.
9603 If the size was given by a nontype template parameter N, the maximum
9604 value will have the form N-1. The flag says that we can (and indeed
9605 must) unify N with (ARG + 1), an exception to the normal rules on
9609 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9614 int strict_in = strict;
9616 /* I don't think this will do the right thing with respect to types.
9617 But the only case I've seen it in so far has been array bounds, where
9618 signedness is the only information lost, and I think that will be
9620 while (TREE_CODE (parm) == NOP_EXPR)
9621 parm = TREE_OPERAND (parm, 0);
9623 if (arg == error_mark_node)
9625 if (arg == unknown_type_node)
9626 /* We can't deduce anything from this, but we might get all the
9627 template args from other function args. */
9630 /* If PARM uses template parameters, then we can't bail out here,
9631 even if ARG == PARM, since we won't record unifications for the
9632 template parameters. We might need them if we're trying to
9633 figure out which of two things is more specialized. */
9634 if (arg == parm && !uses_template_parms (parm))
9637 /* Immediately reject some pairs that won't unify because of
9638 cv-qualification mismatches. */
9639 if (TREE_CODE (arg) == TREE_CODE (parm)
9641 /* It is the elements of the array which hold the cv quals of an array
9642 type, and the elements might be template type parms. We'll check
9644 && TREE_CODE (arg) != ARRAY_TYPE
9645 /* We check the cv-qualifiers when unifying with template type
9646 parameters below. We want to allow ARG `const T' to unify with
9647 PARM `T' for example, when computing which of two templates
9648 is more specialized, for example. */
9649 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9650 && !check_cv_quals_for_unify (strict_in, arg, parm))
9653 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9654 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9655 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9656 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9657 strict &= ~UNIFY_ALLOW_DERIVED;
9658 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9659 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9660 strict &= ~UNIFY_ALLOW_MAX_CORRECTION;
9662 switch (TREE_CODE (parm))
9666 case UNBOUND_CLASS_TEMPLATE:
9667 /* In a type which contains a nested-name-specifier, template
9668 argument values cannot be deduced for template parameters used
9669 within the nested-name-specifier. */
9672 case TEMPLATE_TYPE_PARM:
9673 case TEMPLATE_TEMPLATE_PARM:
9674 case BOUND_TEMPLATE_TEMPLATE_PARM:
9675 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9677 if (TEMPLATE_TYPE_LEVEL (parm)
9678 != template_decl_level (tparm))
9679 /* The PARM is not one we're trying to unify. Just check
9680 to see if it matches ARG. */
9681 return (TREE_CODE (arg) == TREE_CODE (parm)
9682 && same_type_p (parm, arg)) ? 0 : 1;
9683 idx = TEMPLATE_TYPE_IDX (parm);
9684 targ = TREE_VEC_ELT (targs, idx);
9685 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9687 /* Check for mixed types and values. */
9688 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9689 && TREE_CODE (tparm) != TYPE_DECL)
9690 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9691 && TREE_CODE (tparm) != TEMPLATE_DECL))
9694 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9696 /* ARG must be constructed from a template class or a template
9697 template parameter. */
9698 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9699 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9703 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9704 tree parmvec = TYPE_TI_ARGS (parm);
9705 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9707 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9710 /* The parameter and argument roles have to be switched here
9711 in order to handle default arguments properly. For example,
9712 template<template <class> class TT> void f(TT<int>)
9713 should be able to accept vector<int> which comes from
9714 template <class T, class Allocator = allocator>
9717 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9721 /* Deduce arguments T, i from TT<T> or TT<i>.
9722 We check each element of PARMVEC and ARGVEC individually
9723 rather than the whole TREE_VEC since they can have
9724 different number of elements. */
9726 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9728 if (unify (tparms, targs,
9729 TREE_VEC_ELT (parmvec, i),
9730 TREE_VEC_ELT (argvec, i),
9735 arg = TYPE_TI_TEMPLATE (arg);
9737 /* Fall through to deduce template name. */
9740 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9741 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9743 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9745 /* Simple cases: Value already set, does match or doesn't. */
9746 if (targ != NULL_TREE && template_args_equal (targ, arg))
9753 /* If PARM is `const T' and ARG is only `int', we don't have
9754 a match unless we are allowing additional qualification.
9755 If ARG is `const int' and PARM is just `T' that's OK;
9756 that binds `const int' to `T'. */
9757 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
9761 /* Consider the case where ARG is `const volatile int' and
9762 PARM is `const T'. Then, T should be `volatile int'. */
9763 arg = cp_build_qualified_type_real
9764 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
9765 if (arg == error_mark_node)
9768 /* Simple cases: Value already set, does match or doesn't. */
9769 if (targ != NULL_TREE && same_type_p (targ, arg))
9774 /* Make sure that ARG is not a variable-sized array. (Note
9775 that were talking about variable-sized arrays (like
9776 `int[n]'), rather than arrays of unknown size (like
9777 `int[]').) We'll get very confused by such a type since
9778 the bound of the array will not be computable in an
9779 instantiation. Besides, such types are not allowed in
9780 ISO C++, so we can do as we please here. */
9781 if (variably_modified_type_p (arg, NULL_TREE))
9785 TREE_VEC_ELT (targs, idx) = arg;
9788 case TEMPLATE_PARM_INDEX:
9789 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9791 if (TEMPLATE_PARM_LEVEL (parm)
9792 != template_decl_level (tparm))
9793 /* The PARM is not one we're trying to unify. Just check
9794 to see if it matches ARG. */
9795 return !(TREE_CODE (arg) == TREE_CODE (parm)
9796 && cp_tree_equal (parm, arg));
9798 idx = TEMPLATE_PARM_IDX (parm);
9799 targ = TREE_VEC_ELT (targs, idx);
9802 return !cp_tree_equal (targ, arg);
9804 /* [temp.deduct.type] If, in the declaration of a function template
9805 with a non-type template-parameter, the non-type
9806 template-parameter is used in an expression in the function
9807 parameter-list and, if the corresponding template-argument is
9808 deduced, the template-argument type shall match the type of the
9809 template-parameter exactly, except that a template-argument
9810 deduced from an array bound may be of any integral type.
9811 The non-type parameter might use already deduced type parameters. */
9812 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
9813 if (!TREE_TYPE (arg))
9814 /* Template-parameter dependent expression. Just accept it for now.
9815 It will later be processed in convert_template_argument. */
9817 else if (same_type_p (TREE_TYPE (arg), tparm))
9819 else if ((strict & UNIFY_ALLOW_INTEGER)
9820 && (TREE_CODE (tparm) == INTEGER_TYPE
9821 || TREE_CODE (tparm) == BOOLEAN_TYPE))
9823 else if (uses_template_parms (tparm))
9824 /* We haven't deduced the type of this parameter yet. Try again
9830 TREE_VEC_ELT (targs, idx) = arg;
9835 /* A pointer-to-member constant can be unified only with
9836 another constant. */
9837 if (TREE_CODE (arg) != PTRMEM_CST)
9840 /* Just unify the class member. It would be useless (and possibly
9841 wrong, depending on the strict flags) to unify also
9842 PTRMEM_CST_CLASS, because we want to be sure that both parm and
9843 arg refer to the same variable, even if through different
9844 classes. For instance:
9846 struct A { int x; };
9849 Unification of &A::x and &B::x must succeed. */
9850 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
9851 PTRMEM_CST_MEMBER (arg), strict);
9856 if (TREE_CODE (arg) != POINTER_TYPE)
9859 /* [temp.deduct.call]
9861 A can be another pointer or pointer to member type that can
9862 be converted to the deduced A via a qualification
9863 conversion (_conv.qual_).
9865 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
9866 This will allow for additional cv-qualification of the
9867 pointed-to types if appropriate. */
9869 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
9870 /* The derived-to-base conversion only persists through one
9871 level of pointers. */
9872 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
9874 return unify (tparms, targs, TREE_TYPE (parm),
9875 TREE_TYPE (arg), strict);
9878 case REFERENCE_TYPE:
9879 if (TREE_CODE (arg) != REFERENCE_TYPE)
9881 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9882 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9885 if (TREE_CODE (arg) != ARRAY_TYPE)
9887 if ((TYPE_DOMAIN (parm) == NULL_TREE)
9888 != (TYPE_DOMAIN (arg) == NULL_TREE))
9890 if (TYPE_DOMAIN (parm) != NULL_TREE
9891 && unify (tparms, targs, TYPE_DOMAIN (parm),
9892 TYPE_DOMAIN (arg), UNIFY_ALLOW_NONE) != 0)
9894 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9895 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9903 if (TREE_CODE (arg) != TREE_CODE (parm))
9906 if (TREE_CODE (parm) == INTEGER_TYPE
9907 && TREE_CODE (TYPE_MAX_VALUE (parm)) != INTEGER_CST)
9909 if (TYPE_MIN_VALUE (parm) && TYPE_MIN_VALUE (arg)
9910 && unify (tparms, targs, TYPE_MIN_VALUE (parm),
9911 TYPE_MIN_VALUE (arg), UNIFY_ALLOW_INTEGER))
9913 if (TYPE_MAX_VALUE (parm) && TYPE_MAX_VALUE (arg)
9914 && unify (tparms, targs, TYPE_MAX_VALUE (parm),
9915 TYPE_MAX_VALUE (arg),
9916 UNIFY_ALLOW_INTEGER | UNIFY_ALLOW_MAX_CORRECTION))
9919 /* We have already checked cv-qualification at the top of the
9921 else if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
9924 /* As far as unification is concerned, this wins. Later checks
9925 will invalidate it if necessary. */
9928 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
9929 /* Type INTEGER_CST can come from ordinary constant template args. */
9931 while (TREE_CODE (arg) == NOP_EXPR)
9932 arg = TREE_OPERAND (arg, 0);
9934 if (TREE_CODE (arg) != INTEGER_CST)
9936 return !tree_int_cst_equal (parm, arg);
9941 if (TREE_CODE (arg) != TREE_VEC)
9943 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
9945 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
9946 if (unify (tparms, targs,
9947 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
9955 if (TREE_CODE (arg) != TREE_CODE (parm))
9958 if (TYPE_PTRMEMFUNC_P (parm))
9960 if (!TYPE_PTRMEMFUNC_P (arg))
9963 return unify (tparms, targs,
9964 TYPE_PTRMEMFUNC_FN_TYPE (parm),
9965 TYPE_PTRMEMFUNC_FN_TYPE (arg),
9969 if (CLASSTYPE_TEMPLATE_INFO (parm))
9973 if (strict_in & UNIFY_ALLOW_DERIVED)
9975 /* First, we try to unify the PARM and ARG directly. */
9976 t = try_class_unification (tparms, targs,
9981 /* Fallback to the special case allowed in
9984 If P is a class, and P has the form
9985 template-id, then A can be a derived class of
9986 the deduced A. Likewise, if P is a pointer to
9987 a class of the form template-id, A can be a
9988 pointer to a derived class pointed to by the
9990 t = get_template_base (tparms, targs,
9993 if (! t || t == error_mark_node)
9997 else if (CLASSTYPE_TEMPLATE_INFO (arg)
9998 && (CLASSTYPE_TI_TEMPLATE (parm)
9999 == CLASSTYPE_TI_TEMPLATE (arg)))
10000 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10001 Then, we should unify `int' and `U'. */
10004 /* There's no chance of unification succeeding. */
10007 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10008 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10010 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10015 case FUNCTION_TYPE:
10016 if (TREE_CODE (arg) != TREE_CODE (parm))
10019 if (unify (tparms, targs, TREE_TYPE (parm),
10020 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10022 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10023 TYPE_ARG_TYPES (arg), 1,
10024 DEDUCE_EXACT, 0, -1);
10027 if (TREE_CODE (arg) != OFFSET_TYPE)
10029 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10030 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10032 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10036 if (DECL_TEMPLATE_PARM_P (parm))
10037 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10038 if (arg != decl_constant_value (parm))
10043 case TEMPLATE_DECL:
10044 /* Matched cases are handled by the ARG == PARM test above. */
10048 if (tree_int_cst_equal (TREE_OPERAND (parm, 1), integer_one_node)
10049 && (strict_in & UNIFY_ALLOW_MAX_CORRECTION))
10051 /* We handle this case specially, since it comes up with
10052 arrays. In particular, something like:
10054 template <int N> void f(int (&x)[N]);
10056 Here, we are trying to unify the range type, which
10057 looks like [0 ... (N - 1)]. */
10059 t1 = TREE_OPERAND (parm, 0);
10060 t2 = TREE_OPERAND (parm, 1);
10062 t = fold (build (PLUS_EXPR, integer_type_node, arg, t2));
10064 return unify (tparms, targs, t1, t, strict);
10066 /* Else fall through. */
10069 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (parm))))
10072 /* We're looking at an expression. This can happen with
10076 void foo(S<I>, S<I + 2>);
10078 This is a "nondeduced context":
10082 The nondeduced contexts are:
10084 --A type that is a template-id in which one or more of
10085 the template-arguments is an expression that references
10086 a template-parameter.
10088 In these cases, we assume deduction succeeded, but don't
10089 actually infer any unifications. */
10091 if (!uses_template_parms (parm)
10092 && !template_args_equal (parm, arg))
10098 sorry ("use of `%s' in template type unification",
10099 tree_code_name [(int) TREE_CODE (parm)]);
10105 /* Note that DECL can be defined in this translation unit, if
10109 mark_definable (tree decl)
10112 DECL_NOT_REALLY_EXTERN (decl) = 1;
10113 FOR_EACH_CLONE (clone, decl)
10114 DECL_NOT_REALLY_EXTERN (clone) = 1;
10117 /* Called if RESULT is explicitly instantiated, or is a member of an
10118 explicitly instantiated class. */
10121 mark_decl_instantiated (tree result, int extern_p)
10123 SET_DECL_EXPLICIT_INSTANTIATION (result);
10125 /* If this entity has already been written out, it's too late to
10126 make any modifications. */
10127 if (TREE_ASM_WRITTEN (result))
10130 if (TREE_CODE (result) != FUNCTION_DECL)
10131 /* The TREE_PUBLIC flag for function declarations will have been
10132 set correctly by tsubst. */
10133 TREE_PUBLIC (result) = 1;
10135 /* This might have been set by an earlier implicit instantiation. */
10136 DECL_COMDAT (result) = 0;
10139 DECL_NOT_REALLY_EXTERN (result) = 0;
10142 mark_definable (result);
10143 /* Always make artificials weak. */
10144 if (DECL_ARTIFICIAL (result) && flag_weak)
10145 comdat_linkage (result);
10146 /* For WIN32 we also want to put explicit instantiations in
10147 linkonce sections. */
10148 else if (TREE_PUBLIC (result))
10149 maybe_make_one_only (result);
10152 /* If EXTERN_P, then this function will not be emitted -- unless
10153 followed by an explicit instantiation, at which point its linkage
10154 will be adjusted. If !EXTERN_P, then this function will be
10155 emitted here. In neither circumstance do we want
10156 import_export_decl to adjust the linkage. */
10157 DECL_INTERFACE_KNOWN (result) = 1;
10160 /* Given two function templates PAT1 and PAT2, return:
10162 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
10164 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10165 -1 if PAT2 is more specialized than PAT1.
10166 0 if neither is more specialized.
10168 LEN is passed through to fn_type_unification. */
10171 more_specialized (tree pat1, tree pat2, int deduce, int len)
10176 /* If template argument deduction succeeds, we substitute the
10177 resulting arguments into non-deduced contexts. While doing that,
10178 we must be aware that we may encounter dependent types. */
10179 ++processing_template_decl;
10180 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
10181 NULL_TREE, 0, deduce, len);
10185 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
10186 NULL_TREE, 0, deduce, len);
10189 --processing_template_decl;
10194 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10196 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10197 -1 if PAT2 is more specialized than PAT1.
10198 0 if neither is more specialized.
10200 FULL_ARGS is the full set of template arguments that triggers this
10201 partial ordering. */
10204 more_specialized_class (tree pat1, tree pat2, tree full_args)
10209 /* Just like what happens for functions, if we are ordering between
10210 different class template specializations, we may encounter dependent
10211 types in the arguments, and we need our dependency check functions
10212 to behave correctly. */
10213 ++processing_template_decl;
10214 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10215 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10219 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10220 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10223 --processing_template_decl;
10228 /* Return the template arguments that will produce the function signature
10229 DECL from the function template FN, with the explicit template
10230 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
10231 also match. Return NULL_TREE if no satisfactory arguments could be
10232 found. DEDUCE and LEN are passed through to fn_type_unification. */
10235 get_bindings_real (tree fn,
10237 tree explicit_args,
10242 int ntparms = DECL_NTPARMS (fn);
10243 tree targs = make_tree_vec (ntparms);
10245 tree decl_arg_types;
10248 /* Substitute the explicit template arguments into the type of DECL.
10249 The call to fn_type_unification will handle substitution into the
10251 decl_type = TREE_TYPE (decl);
10252 if (explicit_args && uses_template_parms (decl_type))
10255 tree converted_args;
10257 if (DECL_TEMPLATE_INFO (decl))
10258 tmpl = DECL_TI_TEMPLATE (decl);
10260 /* We can get here for some invalid specializations. */
10264 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10265 explicit_args, NULL_TREE,
10266 tf_none, /*require_all_arguments=*/0));
10267 if (converted_args == error_mark_node)
10270 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10271 if (decl_type == error_mark_node)
10275 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10276 /* Never do unification on the 'this' parameter. */
10277 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10278 decl_arg_types = TREE_CHAIN (decl_arg_types);
10280 i = fn_type_unification (fn, explicit_args, targs,
10282 (check_rettype || DECL_CONV_FN_P (fn)
10283 ? TREE_TYPE (decl_type) : NULL_TREE),
10292 /* For most uses, we want to check the return type. */
10295 get_bindings (tree fn, tree decl, tree explicit_args)
10297 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10300 /* But for resolve_overloaded_unification, we only care about the parameter
10304 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10306 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10309 /* Return the innermost template arguments that, when applied to a
10310 template specialization whose innermost template parameters are
10311 TPARMS, and whose specialization arguments are PARMS, yield the
10314 For example, suppose we have:
10316 template <class T, class U> struct S {};
10317 template <class T> struct S<T*, int> {};
10319 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10320 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10321 int}. The resulting vector will be {double}, indicating that `T'
10322 is bound to `double'. */
10325 get_class_bindings (tree tparms, tree parms, tree args)
10327 int i, ntparms = TREE_VEC_LENGTH (tparms);
10328 tree vec = make_tree_vec (ntparms);
10330 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10334 for (i = 0; i < ntparms; ++i)
10335 if (! TREE_VEC_ELT (vec, i))
10338 if (verify_class_unification (vec, parms, args))
10344 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10345 Pick the most specialized template, and return the corresponding
10346 instantiation, or if there is no corresponding instantiation, the
10347 template itself. If there is no most specialized template,
10348 error_mark_node is returned. If there are no templates at all,
10349 NULL_TREE is returned. */
10352 most_specialized_instantiation (tree instantiations)
10357 if (!instantiations)
10360 champ = instantiations;
10361 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10363 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10371 fn = TREE_CHAIN (fn);
10373 return error_mark_node;
10379 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10381 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10384 return error_mark_node;
10387 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10390 /* Return the most specialized of the list of templates in FNS that can
10391 produce an instantiation matching DECL, given the explicit template
10392 arguments EXPLICIT_ARGS. */
10395 most_specialized (tree fns, tree decl, tree explicit_args)
10397 tree candidates = NULL_TREE;
10400 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10402 tree candidate = TREE_VALUE (fn);
10404 args = get_bindings (candidate, decl, explicit_args);
10406 candidates = tree_cons (NULL_TREE, candidate, candidates);
10409 return most_specialized_instantiation (candidates);
10412 /* If DECL is a specialization of some template, return the most
10413 general such template. Otherwise, returns NULL_TREE.
10415 For example, given:
10417 template <class T> struct S { template <class U> void f(U); };
10419 if TMPL is `template <class U> void S<int>::f(U)' this will return
10420 the full template. This function will not trace past partial
10421 specializations, however. For example, given in addition:
10423 template <class T> struct S<T*> { template <class U> void f(U); };
10425 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10426 `template <class T> template <class U> S<T*>::f(U)'. */
10429 most_general_template (tree decl)
10431 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10432 an immediate specialization. */
10433 if (TREE_CODE (decl) == FUNCTION_DECL)
10435 if (DECL_TEMPLATE_INFO (decl)) {
10436 decl = DECL_TI_TEMPLATE (decl);
10438 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10439 template friend. */
10440 if (TREE_CODE (decl) != TEMPLATE_DECL)
10446 /* Look for more and more general templates. */
10447 while (DECL_TEMPLATE_INFO (decl))
10449 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10450 (See cp-tree.h for details.) */
10451 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10454 if (CLASS_TYPE_P (TREE_TYPE (decl))
10455 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10458 /* Stop if we run into an explicitly specialized class template. */
10459 if (!DECL_NAMESPACE_SCOPE_P (decl)
10460 && DECL_CONTEXT (decl)
10461 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10464 decl = DECL_TI_TEMPLATE (decl);
10470 /* Return the most specialized of the class template specializations
10471 of TMPL which can produce an instantiation matching ARGS, or
10472 error_mark_node if the choice is ambiguous. */
10475 most_specialized_class (tree tmpl, tree args)
10477 tree list = NULL_TREE;
10482 tmpl = most_general_template (tmpl);
10483 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10486 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10489 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10490 TREE_TYPE (list) = TREE_TYPE (t);
10499 t = TREE_CHAIN (t);
10500 for (; t; t = TREE_CHAIN (t))
10502 fate = more_specialized_class (champ, t, args);
10509 t = TREE_CHAIN (t);
10511 return error_mark_node;
10517 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10519 fate = more_specialized_class (champ, t, args);
10521 return error_mark_node;
10527 /* Explicitly instantiate DECL. */
10530 do_decl_instantiation (tree decl, tree storage)
10532 tree result = NULL_TREE;
10536 /* An error occurred, for which grokdeclarator has already issued
10537 an appropriate message. */
10539 else if (! DECL_LANG_SPECIFIC (decl))
10541 error ("explicit instantiation of non-template `%#D'", decl);
10544 else if (TREE_CODE (decl) == VAR_DECL)
10546 /* There is an asymmetry here in the way VAR_DECLs and
10547 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10548 the latter, the DECL we get back will be marked as a
10549 template instantiation, and the appropriate
10550 DECL_TEMPLATE_INFO will be set up. This does not happen for
10551 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10552 should handle VAR_DECLs as it currently handles
10554 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10555 if (!result || TREE_CODE (result) != VAR_DECL)
10557 error ("no matching template for `%D' found", decl);
10561 else if (TREE_CODE (decl) != FUNCTION_DECL)
10563 error ("explicit instantiation of `%#D'", decl);
10569 /* Check for various error cases. Note that if the explicit
10570 instantiation is valid the RESULT will currently be marked as an
10571 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10572 until we get here. */
10574 if (DECL_TEMPLATE_SPECIALIZATION (result))
10576 /* DR 259 [temp.spec].
10578 Both an explicit instantiation and a declaration of an explicit
10579 specialization shall not appear in a program unless the explicit
10580 instantiation follows a declaration of the explicit specialization.
10582 For a given set of template parameters, if an explicit
10583 instantiation of a template appears after a declaration of an
10584 explicit specialization for that template, the explicit
10585 instantiation has no effect. */
10588 else if (DECL_EXPLICIT_INSTANTIATION (result))
10592 No program shall explicitly instantiate any template more
10595 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10596 the first instantiation was `extern' and the second is not,
10597 and EXTERN_P for the opposite case. */
10598 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10599 pedwarn ("duplicate explicit instantiation of `%#D'", result);
10600 /* If an "extern" explicit instantiation follows an ordinary
10601 explicit instantiation, the template is instantiated. */
10605 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10607 error ("no matching template for `%D' found", result);
10610 else if (!DECL_TEMPLATE_INFO (result))
10612 pedwarn ("explicit instantiation of non-template `%#D'", result);
10616 if (storage == NULL_TREE)
10618 else if (storage == ridpointers[(int) RID_EXTERN])
10620 if (pedantic && !in_system_header)
10621 pedwarn ("ISO C++ forbids the use of `extern' on explicit instantiations");
10625 error ("storage class `%D' applied to template instantiation",
10628 mark_decl_instantiated (result, extern_p);
10630 instantiate_decl (result, /*defer_ok=*/1, /*undefined_ok=*/0);
10634 mark_class_instantiated (tree t, int extern_p)
10636 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10637 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10638 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10639 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10642 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10643 rest_of_type_compilation (t, 1);
10647 /* Called from do_type_instantiation through binding_table_foreach to
10648 do recursive instantiation for the type bound in ENTRY. */
10650 bt_instantiate_type_proc (binding_entry entry, void *data)
10652 tree storage = *(tree *) data;
10654 if (IS_AGGR_TYPE (entry->type)
10655 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10656 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10659 /* Called from do_type_instantiation to instantiate a member
10660 (a member function or a static member variable) of an
10661 explicitly instantiated class template. */
10663 instantiate_class_member (tree decl, int extern_p)
10665 mark_decl_instantiated (decl, extern_p);
10667 instantiate_decl (decl, /*defer_ok=*/1, /* undefined_ok=*/1);
10670 /* Perform an explicit instantiation of template class T. STORAGE, if
10671 non-null, is the RID for extern, inline or static. COMPLAIN is
10672 nonzero if this is called from the parser, zero if called recursively,
10673 since the standard is unclear (as detailed below). */
10676 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10681 int previous_instantiation_extern_p = 0;
10683 if (TREE_CODE (t) == TYPE_DECL)
10686 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10688 error ("explicit instantiation of non-template type `%T'", t);
10694 if (!COMPLETE_TYPE_P (t))
10696 if (complain & tf_error)
10697 error ("explicit instantiation of `%#T' before definition of template",
10702 if (storage != NULL_TREE)
10704 if (pedantic && !in_system_header)
10705 pedwarn("ISO C++ forbids the use of `%E' on explicit instantiations",
10708 if (storage == ridpointers[(int) RID_INLINE])
10710 else if (storage == ridpointers[(int) RID_EXTERN])
10712 else if (storage == ridpointers[(int) RID_STATIC])
10716 error ("storage class `%D' applied to template instantiation",
10722 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10724 /* DR 259 [temp.spec].
10726 Both an explicit instantiation and a declaration of an explicit
10727 specialization shall not appear in a program unless the explicit
10728 instantiation follows a declaration of the explicit specialization.
10730 For a given set of template parameters, if an explicit
10731 instantiation of a template appears after a declaration of an
10732 explicit specialization for that template, the explicit
10733 instantiation has no effect. */
10736 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10740 No program shall explicitly instantiate any template more
10743 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
10744 instantiation was `extern'. If EXTERN_P then the second is.
10745 These cases are OK. */
10746 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
10748 if (!previous_instantiation_extern_p && !extern_p
10749 && (complain & tf_error))
10750 pedwarn ("duplicate explicit instantiation of `%#T'", t);
10752 /* If we've already instantiated the template, just return now. */
10753 if (!CLASSTYPE_INTERFACE_ONLY (t))
10757 mark_class_instantiated (t, extern_p);
10765 /* In contrast to implicit instantiation, where only the
10766 declarations, and not the definitions, of members are
10767 instantiated, we have here:
10771 The explicit instantiation of a class template specialization
10772 implies the instantiation of all of its members not
10773 previously explicitly specialized in the translation unit
10774 containing the explicit instantiation.
10776 Of course, we can't instantiate member template classes, since
10777 we don't have any arguments for them. Note that the standard
10778 is unclear on whether the instantiation of the members are
10779 *explicit* instantiations or not. However, the most natural
10780 interpretation is that it should be an explicit instantiation. */
10783 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
10784 if (TREE_CODE (tmp) == FUNCTION_DECL
10785 && DECL_TEMPLATE_INSTANTIATION (tmp))
10786 instantiate_class_member (tmp, extern_p);
10788 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
10789 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
10790 instantiate_class_member (tmp, extern_p);
10792 if (CLASSTYPE_NESTED_UTDS (t))
10793 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
10794 bt_instantiate_type_proc, &storage);
10798 /* Given a function DECL, which is a specialization of TMPL, modify
10799 DECL to be a re-instantiation of TMPL with the same template
10800 arguments. TMPL should be the template into which tsubst'ing
10801 should occur for DECL, not the most general template.
10803 One reason for doing this is a scenario like this:
10806 void f(const T&, int i);
10808 void g() { f(3, 7); }
10811 void f(const T& t, const int i) { }
10813 Note that when the template is first instantiated, with
10814 instantiate_template, the resulting DECL will have no name for the
10815 first parameter, and the wrong type for the second. So, when we go
10816 to instantiate the DECL, we regenerate it. */
10819 regenerate_decl_from_template (tree decl, tree tmpl)
10821 /* The most general version of TMPL. */
10823 /* The arguments used to instantiate DECL, from the most general
10830 args = DECL_TI_ARGS (decl);
10831 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
10833 /* Unregister the specialization so that when we tsubst we will not
10834 just return DECL. We don't have to unregister DECL from TMPL
10835 because if would only be registered there if it were a partial
10836 instantiation of a specialization, which it isn't: it's a full
10838 gen_tmpl = most_general_template (tmpl);
10839 unregistered = reregister_specialization (decl, gen_tmpl,
10840 /*new_spec=*/NULL_TREE);
10842 /* If the DECL was not unregistered then something peculiar is
10843 happening: we created a specialization but did not call
10844 register_specialization for it. */
10845 my_friendly_assert (unregistered, 0);
10847 /* Make sure that we can see identifiers, and compute access
10849 push_access_scope (decl);
10851 /* Do the substitution to get the new declaration. */
10852 new_decl = tsubst (code_pattern, args, tf_error, NULL_TREE);
10854 if (TREE_CODE (decl) == VAR_DECL)
10856 /* Set up DECL_INITIAL, since tsubst doesn't. */
10857 if (!DECL_INITIALIZED_IN_CLASS_P (decl))
10858 DECL_INITIAL (new_decl) =
10859 tsubst_expr (DECL_INITIAL (code_pattern), args,
10860 tf_error, DECL_TI_TEMPLATE (decl));
10862 else if (TREE_CODE (decl) == FUNCTION_DECL)
10864 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
10866 DECL_INITIAL (new_decl) = error_mark_node;
10867 /* And don't complain about a duplicate definition. */
10868 DECL_INITIAL (decl) = NULL_TREE;
10871 pop_access_scope (decl);
10873 /* The immediate parent of the new template is still whatever it was
10874 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
10875 general template. We also reset the DECL_ASSEMBLER_NAME since
10876 tsubst always calculates the name as if the function in question
10877 were really a template instance, and sometimes, with friend
10878 functions, this is not so. See tsubst_friend_function for
10880 DECL_TI_TEMPLATE (new_decl) = DECL_TI_TEMPLATE (decl);
10881 COPY_DECL_ASSEMBLER_NAME (decl, new_decl);
10882 COPY_DECL_RTL (decl, new_decl);
10883 DECL_USE_TEMPLATE (new_decl) = DECL_USE_TEMPLATE (decl);
10885 /* Call duplicate decls to merge the old and new declarations. */
10886 duplicate_decls (new_decl, decl);
10888 /* Now, re-register the specialization. */
10889 register_specialization (decl, gen_tmpl, args);
10892 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
10893 substituted to get DECL. */
10896 template_for_substitution (tree decl)
10898 tree tmpl = DECL_TI_TEMPLATE (decl);
10900 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
10901 for the instantiation. This is not always the most general
10902 template. Consider, for example:
10905 struct S { template <class U> void f();
10906 template <> void f<int>(); };
10908 and an instantiation of S<double>::f<int>. We want TD to be the
10909 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
10910 while (/* An instantiation cannot have a definition, so we need a
10911 more general template. */
10912 DECL_TEMPLATE_INSTANTIATION (tmpl)
10913 /* We must also deal with friend templates. Given:
10915 template <class T> struct S {
10916 template <class U> friend void f() {};
10919 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
10920 so far as the language is concerned, but that's still
10921 where we get the pattern for the instantiation from. On
10922 other hand, if the definition comes outside the class, say:
10924 template <class T> struct S {
10925 template <class U> friend void f();
10927 template <class U> friend void f() {}
10929 we don't need to look any further. That's what the check for
10930 DECL_INITIAL is for. */
10931 || (TREE_CODE (decl) == FUNCTION_DECL
10932 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
10933 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
10935 /* The present template, TD, should not be a definition. If it
10936 were a definition, we should be using it! Note that we
10937 cannot restructure the loop to just keep going until we find
10938 a template with a definition, since that might go too far if
10939 a specialization was declared, but not defined. */
10940 my_friendly_assert (!(TREE_CODE (decl) == VAR_DECL
10941 && !DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl))),
10944 /* Fetch the more general template. */
10945 tmpl = DECL_TI_TEMPLATE (tmpl);
10951 /* Produce the definition of D, a _DECL generated from a template. If
10952 DEFER_OK is nonzero, then we don't have to actually do the
10953 instantiation now; we just have to do it sometime. Normally it is
10954 an error if this is an explicit instantiation but D is undefined.
10955 If UNDEFINED_OK is nonzero, then instead we treat it as an implicit
10956 instantiation. UNDEFINED_OK is nonzero only if we are being used
10957 to instantiate the members of an explicitly instantiated class
10962 instantiate_decl (tree d, int defer_ok, int undefined_ok)
10964 tree tmpl = DECL_TI_TEMPLATE (d);
10971 int pattern_defined;
10973 location_t saved_loc = input_location;
10975 /* This function should only be used to instantiate templates for
10976 functions and static member variables. */
10977 my_friendly_assert (TREE_CODE (d) == FUNCTION_DECL
10978 || TREE_CODE (d) == VAR_DECL, 0);
10980 /* Variables are never deferred; if instantiation is required, they
10981 are instantiated right away. That allows for better code in the
10982 case that an expression refers to the value of the variable --
10983 if the variable has a constant value the referring expression can
10984 take advantage of that fact. */
10985 if (TREE_CODE (d) == VAR_DECL)
10988 /* Don't instantiate cloned functions. Instead, instantiate the
10989 functions they cloned. */
10990 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
10991 d = DECL_CLONED_FUNCTION (d);
10993 if (DECL_TEMPLATE_INSTANTIATED (d))
10994 /* D has already been instantiated. It might seem reasonable to
10995 check whether or not D is an explicit instantiation, and, if so,
10996 stop here. But when an explicit instantiation is deferred
10997 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
10998 is set, even though we still need to do the instantiation. */
11001 /* If we already have a specialization of this declaration, then
11002 there's no reason to instantiate it. Note that
11003 retrieve_specialization gives us both instantiations and
11004 specializations, so we must explicitly check
11005 DECL_TEMPLATE_SPECIALIZATION. */
11006 gen_tmpl = most_general_template (tmpl);
11007 gen_args = DECL_TI_ARGS (d);
11008 spec = retrieve_specialization (gen_tmpl, gen_args);
11009 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11012 /* This needs to happen before any tsubsting. */
11013 if (! push_tinst_level (d))
11016 timevar_push (TV_PARSE);
11018 /* We may be in the middle of deferred access check. Disable it now. */
11019 push_deferring_access_checks (dk_no_deferred);
11021 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11022 for the instantiation. */
11023 td = template_for_substitution (d);
11024 code_pattern = DECL_TEMPLATE_RESULT (td);
11026 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11027 || DECL_TEMPLATE_SPECIALIZATION (td))
11028 /* In the case of a friend template whose definition is provided
11029 outside the class, we may have too many arguments. Drop the
11030 ones we don't need. The same is true for specializations. */
11031 args = get_innermost_template_args
11032 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11036 if (TREE_CODE (d) == FUNCTION_DECL)
11037 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11039 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11040 /* Unless an explicit instantiation directive has already determined
11041 the linkage of D, remember that a definition is available for
11043 if (pattern_defined
11044 && !DECL_INTERFACE_KNOWN (d)
11045 && !DECL_NOT_REALLY_EXTERN (d))
11046 mark_definable (d);
11048 input_location = DECL_SOURCE_LOCATION (d);
11050 if (! pattern_defined && DECL_EXPLICIT_INSTANTIATION (d) && undefined_ok)
11052 DECL_NOT_REALLY_EXTERN (d) = 0;
11053 SET_DECL_IMPLICIT_INSTANTIATION (d);
11058 /* Recheck the substitutions to obtain any warning messages
11059 about ignoring cv qualifiers. */
11060 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11061 tree type = TREE_TYPE (gen);
11063 /* Make sure that we can see identifiers, and compute access
11064 correctly. D is already the target FUNCTION_DECL with the
11066 push_access_scope (d);
11068 if (TREE_CODE (gen) == FUNCTION_DECL)
11070 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11071 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11072 tf_error | tf_warning, d);
11073 /* Don't simply tsubst the function type, as that will give
11074 duplicate warnings about poor parameter qualifications.
11075 The function arguments are the same as the decl_arguments
11076 without the top level cv qualifiers. */
11077 type = TREE_TYPE (type);
11079 tsubst (type, gen_args, tf_error | tf_warning, d);
11081 pop_access_scope (d);
11084 /* We should have set up DECL_INITIAL in instantiate_class_template
11085 for in-class definitions of static data members. */
11086 my_friendly_assert (!(TREE_CODE (d) == VAR_DECL
11087 && DECL_INITIALIZED_IN_CLASS_P (d)
11088 && DECL_INITIAL (d) == NULL_TREE),
11091 /* Do not instantiate templates that we know will be defined
11093 if (DECL_INTERFACE_KNOWN (d)
11094 && DECL_REALLY_EXTERN (d)
11095 && ! (TREE_CODE (d) == FUNCTION_DECL
11096 && DECL_INLINE (d)))
11098 /* Defer all other templates, unless we have been explicitly
11099 forbidden from doing so. We restore the source position here
11100 because it's used by add_pending_template. */
11101 else if (! pattern_defined || defer_ok)
11103 input_location = saved_loc;
11105 if (at_eof && !pattern_defined
11106 && DECL_EXPLICIT_INSTANTIATION (d))
11109 The definition of a non-exported function template, a
11110 non-exported member function template, or a non-exported
11111 member function or static data member of a class template
11112 shall be present in every translation unit in which it is
11113 explicitly instantiated. */
11115 ("explicit instantiation of `%D' but no definition available", d);
11117 add_pending_template (d);
11120 /* Tell the repository that D is available in this translation unit
11121 -- and see if it is supposed to be instantiated here. */
11122 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11124 /* In a PCH file, despite the fact that the repository hasn't
11125 requested instantiation in the PCH it is still possible that
11126 an instantiation will be required in a file that includes the
11129 add_pending_template (d);
11130 /* Instantiate inline functions so that the inliner can do its
11131 job, even though we'll not be emitting a copy of this
11133 if (!flag_inline_trees || !DECL_DECLARED_INLINE_P (d))
11137 need_push = !cfun || !global_bindings_p ();
11139 push_to_top_level ();
11141 /* Mark D as instantiated so that recursive calls to
11142 instantiate_decl do not try to instantiate it again. */
11143 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11145 /* Regenerate the declaration in case the template has been modified
11146 by a subsequent redeclaration. */
11147 regenerate_decl_from_template (d, td);
11149 /* We already set the file and line above. Reset them now in case
11150 they changed as a result of calling regenerate_decl_from_template. */
11151 input_location = DECL_SOURCE_LOCATION (d);
11153 if (TREE_CODE (d) == VAR_DECL)
11155 /* Clear out DECL_RTL; whatever was there before may not be right
11156 since we've reset the type of the declaration. */
11157 SET_DECL_RTL (d, NULL_RTX);
11158 DECL_IN_AGGR_P (d) = 0;
11160 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11161 initializer. That function will defer actual emission until
11162 we have a chance to determine linkage. */
11163 DECL_EXTERNAL (d) = 0;
11165 /* Enter the scope of D so that access-checking works correctly. */
11166 push_nested_class (DECL_CONTEXT (d));
11168 (!DECL_INITIALIZED_IN_CLASS_P (d)
11169 ? DECL_INITIAL (d) : NULL_TREE),
11171 pop_nested_class ();
11173 else if (TREE_CODE (d) == FUNCTION_DECL)
11175 htab_t saved_local_specializations;
11180 /* Save away the current list, in case we are instantiating one
11181 template from within the body of another. */
11182 saved_local_specializations = local_specializations;
11184 /* Set up the list of local specializations. */
11185 local_specializations = htab_create (37,
11186 hash_local_specialization,
11187 eq_local_specializations,
11190 /* Set up context. */
11191 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11193 /* Create substitution entries for the parameters. */
11194 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11195 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11196 spec_parm = DECL_ARGUMENTS (d);
11197 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11199 register_local_specialization (spec_parm, tmpl_parm);
11200 spec_parm = skip_artificial_parms_for (d, spec_parm);
11201 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11205 register_local_specialization (spec_parm, tmpl_parm);
11206 tmpl_parm = TREE_CHAIN (tmpl_parm);
11207 spec_parm = TREE_CHAIN (spec_parm);
11209 my_friendly_assert (!spec_parm, 20020813);
11211 /* Substitute into the body of the function. */
11212 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11213 tf_error | tf_warning, tmpl);
11215 /* We don't need the local specializations any more. */
11216 htab_delete (local_specializations);
11217 local_specializations = saved_local_specializations;
11219 /* Finish the function. */
11220 d = finish_function (0);
11221 expand_or_defer_fn (d);
11224 /* We're not deferring instantiation any more. */
11225 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11228 pop_from_top_level ();
11231 input_location = saved_loc;
11232 pop_deferring_access_checks ();
11233 pop_tinst_level ();
11235 timevar_pop (TV_PARSE);
11240 /* Run through the list of templates that we wish we could
11241 instantiate, and instantiate any we can. */
11244 instantiate_pending_templates (void)
11247 tree last = NULL_TREE;
11248 int instantiated_something = 0;
11250 location_t saved_loc = input_location;
11256 t = &pending_templates;
11259 tree instantiation = TREE_VALUE (*t);
11261 reopen_tinst_level (TREE_PURPOSE (*t));
11263 if (TYPE_P (instantiation))
11267 if (!COMPLETE_TYPE_P (instantiation))
11269 instantiate_class_template (instantiation);
11270 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11271 for (fn = TYPE_METHODS (instantiation);
11273 fn = TREE_CHAIN (fn))
11274 if (! DECL_ARTIFICIAL (fn))
11275 instantiate_decl (fn, /*defer_ok=*/0,
11276 /*undefined_ok=*/0);
11277 if (COMPLETE_TYPE_P (instantiation))
11279 instantiated_something = 1;
11284 if (COMPLETE_TYPE_P (instantiation))
11285 /* If INSTANTIATION has been instantiated, then we don't
11286 need to consider it again in the future. */
11287 *t = TREE_CHAIN (*t);
11291 t = &TREE_CHAIN (*t);
11296 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11297 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11299 instantiation = instantiate_decl (instantiation,
11301 /*undefined_ok=*/0);
11302 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11304 instantiated_something = 1;
11309 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11310 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11311 /* If INSTANTIATION has been instantiated, then we don't
11312 need to consider it again in the future. */
11313 *t = TREE_CHAIN (*t);
11317 t = &TREE_CHAIN (*t);
11321 current_tinst_level = NULL_TREE;
11323 last_pending_template = last;
11325 while (reconsider);
11327 input_location = saved_loc;
11328 return instantiated_something;
11331 /* Substitute ARGVEC into T, which is a list of initializers for
11332 either base class or a non-static data member. The TREE_PURPOSEs
11333 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11334 instantiate_decl. */
11337 tsubst_initializer_list (tree t, tree argvec)
11339 tree inits = NULL_TREE;
11341 for (; t; t = TREE_CHAIN (t))
11347 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11349 decl = expand_member_init (decl);
11350 if (decl && !DECL_P (decl))
11351 in_base_initializer = 1;
11353 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11357 else if (TREE_CODE (init) == TREE_LIST)
11358 for (val = init; val; val = TREE_CHAIN (val))
11359 TREE_VALUE (val) = convert_from_reference (TREE_VALUE (val));
11360 else if (init != void_type_node)
11361 init = convert_from_reference (init);
11363 in_base_initializer = 0;
11367 init = build_tree_list (decl, init);
11368 TREE_CHAIN (init) = inits;
11375 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11378 set_current_access_from_decl (tree decl)
11380 if (TREE_PRIVATE (decl))
11381 current_access_specifier = access_private_node;
11382 else if (TREE_PROTECTED (decl))
11383 current_access_specifier = access_protected_node;
11385 current_access_specifier = access_public_node;
11388 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11389 is the instantiation (which should have been created with
11390 start_enum) and ARGS are the template arguments to use. */
11393 tsubst_enum (tree tag, tree newtag, tree args)
11397 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11402 decl = TREE_VALUE (e);
11403 /* Note that in a template enum, the TREE_VALUE is the
11404 CONST_DECL, not the corresponding INTEGER_CST. */
11405 value = tsubst_expr (DECL_INITIAL (decl),
11406 args, tf_error | tf_warning,
11409 /* Give this enumeration constant the correct access. */
11410 set_current_access_from_decl (decl);
11412 /* Actually build the enumerator itself. */
11413 build_enumerator (DECL_NAME (decl), value, newtag);
11416 finish_enum (newtag);
11417 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11418 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11421 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11422 its type -- but without substituting the innermost set of template
11423 arguments. So, innermost set of template parameters will appear in
11427 get_mostly_instantiated_function_type (tree decl)
11435 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11436 targs = DECL_TI_ARGS (decl);
11437 tparms = DECL_TEMPLATE_PARMS (tmpl);
11438 parm_depth = TMPL_PARMS_DEPTH (tparms);
11440 /* There should be as many levels of arguments as there are levels
11442 my_friendly_assert (parm_depth == TMPL_ARGS_DEPTH (targs), 0);
11444 fn_type = TREE_TYPE (tmpl);
11446 if (parm_depth == 1)
11447 /* No substitution is necessary. */
11454 /* Replace the innermost level of the TARGS with NULL_TREEs to
11455 let tsubst know not to substitute for those parameters. */
11456 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11457 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11458 SET_TMPL_ARGS_LEVEL (partial_args, i,
11459 TMPL_ARGS_LEVEL (targs, i));
11460 SET_TMPL_ARGS_LEVEL (partial_args,
11461 TMPL_ARGS_DEPTH (targs),
11462 make_tree_vec (DECL_NTPARMS (tmpl)));
11464 /* Make sure that we can see identifiers, and compute access
11465 correctly. We can just use the context of DECL for the
11466 partial substitution here. It depends only on outer template
11467 parameters, regardless of whether the innermost level is
11468 specialized or not. */
11469 push_access_scope (decl);
11471 ++processing_template_decl;
11472 /* Now, do the (partial) substitution to figure out the
11473 appropriate function type. */
11474 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11475 --processing_template_decl;
11477 /* Substitute into the template parameters to obtain the real
11478 innermost set of parameters. This step is important if the
11479 innermost set of template parameters contains value
11480 parameters whose types depend on outer template parameters. */
11481 TREE_VEC_LENGTH (partial_args)--;
11482 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11484 pop_access_scope (decl);
11490 /* Return truthvalue if we're processing a template different from
11491 the last one involved in diagnostics. */
11493 problematic_instantiation_changed (void)
11495 return last_template_error_tick != tinst_level_tick;
11498 /* Remember current template involved in diagnostics. */
11500 record_last_problematic_instantiation (void)
11502 last_template_error_tick = tinst_level_tick;
11506 current_instantiation (void)
11508 return current_tinst_level;
11511 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11512 type. Return zero for ok, nonzero for disallowed. Issue error and
11513 warning messages under control of COMPLAIN. */
11516 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11518 if (INTEGRAL_TYPE_P (type))
11520 else if (POINTER_TYPE_P (type))
11522 else if (TYPE_PTR_TO_MEMBER_P (type))
11524 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11526 else if (TREE_CODE (type) == TYPENAME_TYPE)
11529 if (complain & tf_error)
11530 error ("`%#T' is not a valid type for a template constant parameter",
11535 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11536 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11539 dependent_type_p_r (tree type)
11545 A type is dependent if it is:
11547 -- a template parameter. Template template parameters are
11548 types for us (since TYPE_P holds true for them) so we
11549 handle them here. */
11550 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11551 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11553 /* -- a qualified-id with a nested-name-specifier which contains a
11554 class-name that names a dependent type or whose unqualified-id
11555 names a dependent type. */
11556 if (TREE_CODE (type) == TYPENAME_TYPE)
11558 /* -- a cv-qualified type where the cv-unqualified type is
11560 type = TYPE_MAIN_VARIANT (type);
11561 /* -- a compound type constructed from any dependent type. */
11562 if (TYPE_PTR_TO_MEMBER_P (type))
11563 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11564 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11566 else if (TREE_CODE (type) == POINTER_TYPE
11567 || TREE_CODE (type) == REFERENCE_TYPE)
11568 return dependent_type_p (TREE_TYPE (type));
11569 else if (TREE_CODE (type) == FUNCTION_TYPE
11570 || TREE_CODE (type) == METHOD_TYPE)
11574 if (dependent_type_p (TREE_TYPE (type)))
11576 for (arg_type = TYPE_ARG_TYPES (type);
11578 arg_type = TREE_CHAIN (arg_type))
11579 if (dependent_type_p (TREE_VALUE (arg_type)))
11583 /* -- an array type constructed from any dependent type or whose
11584 size is specified by a constant expression that is
11585 value-dependent. */
11586 if (TREE_CODE (type) == ARRAY_TYPE)
11588 if (TYPE_DOMAIN (type)
11589 && ((value_dependent_expression_p
11590 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11591 || (type_dependent_expression_p
11592 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11594 return dependent_type_p (TREE_TYPE (type));
11597 /* -- a template-id in which either the template name is a template
11599 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11601 /* ... or any of the template arguments is a dependent type or
11602 an expression that is type-dependent or value-dependent. */
11603 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11604 && (any_dependent_template_arguments_p
11605 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11608 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11609 expression is not type-dependent, then it should already been
11611 if (TREE_CODE (type) == TYPEOF_TYPE)
11614 /* The standard does not specifically mention types that are local
11615 to template functions or local classes, but they should be
11616 considered dependent too. For example:
11618 template <int I> void f() {
11623 The size of `E' cannot be known until the value of `I' has been
11624 determined. Therefore, `E' must be considered dependent. */
11625 scope = TYPE_CONTEXT (type);
11626 if (scope && TYPE_P (scope))
11627 return dependent_type_p (scope);
11628 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11629 return type_dependent_expression_p (scope);
11631 /* Other types are non-dependent. */
11635 /* Returns TRUE if TYPE is dependent, in the sense of
11636 [temp.dep.type]. */
11639 dependent_type_p (tree type)
11641 /* If there are no template parameters in scope, then there can't be
11642 any dependent types. */
11643 if (!processing_template_decl)
11646 /* If the type is NULL, we have not computed a type for the entity
11647 in question; in that case, the type is dependent. */
11651 /* Erroneous types can be considered non-dependent. */
11652 if (type == error_mark_node)
11655 /* If we have not already computed the appropriate value for TYPE,
11657 if (!TYPE_DEPENDENT_P_VALID (type))
11659 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11660 TYPE_DEPENDENT_P_VALID (type) = 1;
11663 return TYPE_DEPENDENT_P (type);
11666 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11669 dependent_scope_ref_p (tree expression, bool criterion (tree))
11674 my_friendly_assert (TREE_CODE (expression) == SCOPE_REF, 20030714);
11676 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11679 scope = TREE_OPERAND (expression, 0);
11680 name = TREE_OPERAND (expression, 1);
11684 An id-expression is type-dependent if it contains a
11685 nested-name-specifier that contains a class-name that names a
11687 /* The suggested resolution to Core Issue 2 implies that if the
11688 qualifying type is the current class, then we must peek
11691 && currently_open_class (scope)
11692 && !criterion (name))
11694 if (dependent_type_p (scope))
11700 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11701 [temp.dep.constexpr] */
11704 value_dependent_expression_p (tree expression)
11706 if (!processing_template_decl)
11709 /* A name declared with a dependent type. */
11710 if (TREE_CODE (expression) == IDENTIFIER_NODE
11711 || (DECL_P (expression)
11712 && type_dependent_expression_p (expression)))
11714 /* A non-type template parameter. */
11715 if ((TREE_CODE (expression) == CONST_DECL
11716 && DECL_TEMPLATE_PARM_P (expression))
11717 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11719 /* A constant with integral or enumeration type and is initialized
11720 with an expression that is value-dependent. */
11721 if (TREE_CODE (expression) == VAR_DECL
11722 && DECL_INITIAL (expression)
11723 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11724 && value_dependent_expression_p (DECL_INITIAL (expression)))
11726 /* These expressions are value-dependent if the type to which the
11727 cast occurs is dependent or the expression being casted is
11728 value-dependent. */
11729 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11730 || TREE_CODE (expression) == STATIC_CAST_EXPR
11731 || TREE_CODE (expression) == CONST_CAST_EXPR
11732 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11733 || TREE_CODE (expression) == CAST_EXPR)
11735 tree type = TREE_TYPE (expression);
11736 if (dependent_type_p (type))
11738 /* A functional cast has a list of operands. */
11739 expression = TREE_OPERAND (expression, 0);
11742 /* If there are no operands, it must be an expression such
11743 as "int()". This should not happen for aggregate types
11744 because it would form non-constant expressions. */
11745 my_friendly_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type),
11750 if (TREE_CODE (expression) == TREE_LIST)
11754 if (value_dependent_expression_p (TREE_VALUE (expression)))
11756 expression = TREE_CHAIN (expression);
11758 while (expression);
11762 return value_dependent_expression_p (expression);
11764 /* A `sizeof' expression is value-dependent if the operand is
11766 if (TREE_CODE (expression) == SIZEOF_EXPR
11767 || TREE_CODE (expression) == ALIGNOF_EXPR)
11769 expression = TREE_OPERAND (expression, 0);
11770 if (TYPE_P (expression))
11771 return dependent_type_p (expression);
11772 return type_dependent_expression_p (expression);
11774 if (TREE_CODE (expression) == SCOPE_REF)
11775 return dependent_scope_ref_p (expression, value_dependent_expression_p);
11776 if (TREE_CODE (expression) == COMPONENT_REF)
11777 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
11778 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
11779 /* A constant expression is value-dependent if any subexpression is
11780 value-dependent. */
11781 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (expression))))
11783 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
11786 return (value_dependent_expression_p
11787 (TREE_OPERAND (expression, 0)));
11790 return ((value_dependent_expression_p
11791 (TREE_OPERAND (expression, 0)))
11792 || (value_dependent_expression_p
11793 (TREE_OPERAND (expression, 1))));
11797 for (i = 0; i < first_rtl_op (TREE_CODE (expression)); ++i)
11798 /* In some cases, some of the operands may be missing.
11799 (For example, in the case of PREDECREMENT_EXPR, the
11800 amount to increment by may be missing.) That doesn't
11801 make the expression dependent. */
11802 if (TREE_OPERAND (expression, i)
11803 && (value_dependent_expression_p
11804 (TREE_OPERAND (expression, i))))
11811 /* The expression is not value-dependent. */
11815 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11816 [temp.dep.expr]. */
11819 type_dependent_expression_p (tree expression)
11821 if (!processing_template_decl)
11824 if (expression == error_mark_node)
11827 /* An unresolved name is always dependent. */
11828 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11831 /* Some expression forms are never type-dependent. */
11832 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
11833 || TREE_CODE (expression) == SIZEOF_EXPR
11834 || TREE_CODE (expression) == ALIGNOF_EXPR
11835 || TREE_CODE (expression) == TYPEID_EXPR
11836 || TREE_CODE (expression) == DELETE_EXPR
11837 || TREE_CODE (expression) == VEC_DELETE_EXPR
11838 || TREE_CODE (expression) == THROW_EXPR)
11841 /* The types of these expressions depends only on the type to which
11842 the cast occurs. */
11843 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11844 || TREE_CODE (expression) == STATIC_CAST_EXPR
11845 || TREE_CODE (expression) == CONST_CAST_EXPR
11846 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11847 || TREE_CODE (expression) == CAST_EXPR)
11848 return dependent_type_p (TREE_TYPE (expression));
11850 /* The types of these expressions depends only on the type created
11851 by the expression. */
11852 if (TREE_CODE (expression) == NEW_EXPR
11853 || TREE_CODE (expression) == VEC_NEW_EXPR)
11855 /* For NEW_EXPR tree nodes created inside a template, either
11856 the object type itself or a TREE_LIST may appear as the
11858 tree type = TREE_OPERAND (expression, 1);
11859 if (TREE_CODE (type) == TREE_LIST)
11860 /* This is an array type. We need to check array dimensions
11862 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
11863 || value_dependent_expression_p
11864 (TREE_OPERAND (TREE_VALUE (type), 1));
11866 return dependent_type_p (type);
11869 if (TREE_CODE (expression) == SCOPE_REF
11870 && dependent_scope_ref_p (expression,
11871 type_dependent_expression_p))
11874 if (TREE_CODE (expression) == FUNCTION_DECL
11875 && DECL_LANG_SPECIFIC (expression)
11876 && DECL_TEMPLATE_INFO (expression)
11877 && (any_dependent_template_arguments_p
11878 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
11881 if (TREE_CODE (expression) == TEMPLATE_DECL
11882 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
11885 if (TREE_TYPE (expression) == unknown_type_node)
11887 if (TREE_CODE (expression) == ADDR_EXPR)
11888 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
11889 if (TREE_CODE (expression) == COMPONENT_REF
11890 || TREE_CODE (expression) == OFFSET_REF)
11892 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
11894 expression = TREE_OPERAND (expression, 1);
11895 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11898 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
11899 if (TREE_CODE (expression) == SCOPE_REF)
11902 if (TREE_CODE (expression) == BASELINK)
11903 expression = BASELINK_FUNCTIONS (expression);
11904 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
11906 if (any_dependent_template_arguments_p
11907 (TREE_OPERAND (expression, 1)))
11909 expression = TREE_OPERAND (expression, 0);
11911 if (TREE_CODE (expression) == OVERLOAD)
11915 if (type_dependent_expression_p (OVL_CURRENT (expression)))
11917 expression = OVL_NEXT (expression);
11924 return (dependent_type_p (TREE_TYPE (expression)));
11927 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
11928 contains a type-dependent expression. */
11931 any_type_dependent_arguments_p (tree args)
11935 tree arg = TREE_VALUE (args);
11937 if (type_dependent_expression_p (arg))
11939 args = TREE_CHAIN (args);
11944 /* Returns TRUE if the ARG (a template argument) is dependent. */
11947 dependent_template_arg_p (tree arg)
11949 if (!processing_template_decl)
11952 if (TREE_CODE (arg) == TEMPLATE_DECL
11953 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11954 return dependent_template_p (arg);
11955 else if (TYPE_P (arg))
11956 return dependent_type_p (arg);
11958 return (type_dependent_expression_p (arg)
11959 || value_dependent_expression_p (arg));
11962 /* Returns true if ARGS (a collection of template arguments) contains
11963 any dependent arguments. */
11966 any_dependent_template_arguments_p (tree args)
11974 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
11976 tree level = TMPL_ARGS_LEVEL (args, i + 1);
11977 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
11978 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
11985 /* Returns TRUE if the template TMPL is dependent. */
11988 dependent_template_p (tree tmpl)
11990 if (TREE_CODE (tmpl) == OVERLOAD)
11994 if (dependent_template_p (OVL_FUNCTION (tmpl)))
11996 tmpl = OVL_CHAIN (tmpl);
12001 /* Template template parameters are dependent. */
12002 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12003 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12005 /* So are qualified names that have not been looked up. */
12006 if (TREE_CODE (tmpl) == SCOPE_REF)
12008 /* So are member templates of dependent classes. */
12009 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12010 return dependent_type_p (DECL_CONTEXT (tmpl));
12014 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12017 dependent_template_id_p (tree tmpl, tree args)
12019 return (dependent_template_p (tmpl)
12020 || any_dependent_template_arguments_p (args));
12023 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12024 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12025 can be found. Note that this function peers inside uninstantiated
12026 templates and therefore should be used only in extremely limited
12030 resolve_typename_type (tree type, bool only_current_p)
12038 my_friendly_assert (TREE_CODE (type) == TYPENAME_TYPE,
12041 scope = TYPE_CONTEXT (type);
12042 name = TYPE_IDENTIFIER (type);
12044 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12045 it first before we can figure out what NAME refers to. */
12046 if (TREE_CODE (scope) == TYPENAME_TYPE)
12047 scope = resolve_typename_type (scope, only_current_p);
12048 /* If we don't know what SCOPE refers to, then we cannot resolve the
12050 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12051 return error_mark_node;
12052 /* If the SCOPE is a template type parameter, we have no way of
12053 resolving the name. */
12054 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12056 /* If the SCOPE is not the current instantiation, there's no reason
12057 to look inside it. */
12058 if (only_current_p && !currently_open_class (scope))
12059 return error_mark_node;
12060 /* If SCOPE is a partial instantiation, it will not have a valid
12061 TYPE_FIELDS list, so use the original template. */
12062 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12063 /* Enter the SCOPE so that name lookup will be resolved as if we
12064 were in the class definition. In particular, SCOPE will no
12065 longer be considered a dependent type. */
12066 pop_p = push_scope (scope);
12067 /* Look up the declaration. */
12068 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12069 /* Obtain the set of qualifiers applied to the TYPE. */
12070 quals = cp_type_quals (type);
12071 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12072 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12074 type = error_mark_node;
12075 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12076 && TREE_CODE (decl) == TYPE_DECL)
12077 type = TREE_TYPE (decl);
12078 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12079 && DECL_CLASS_TEMPLATE_P (decl))
12083 /* Obtain the template and the arguments. */
12084 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12085 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12086 /* Instantiate the template. */
12087 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12088 /*entering_scope=*/0, tf_error | tf_user);
12091 type = error_mark_node;
12092 /* Qualify the resulting type. */
12093 if (type != error_mark_node && quals)
12094 type = cp_build_qualified_type (type, quals);
12095 /* Leave the SCOPE. */
12102 /* EXPR is an expression which is not type-dependent. Return a proxy
12103 for EXPR that can be used to compute the types of larger
12104 expressions containing EXPR. */
12107 build_non_dependent_expr (tree expr)
12111 /* Preserve null pointer constants so that the type of things like
12112 "p == 0" where "p" is a pointer can be determined. */
12113 if (null_ptr_cst_p (expr))
12115 /* Preserve OVERLOADs; the functions must be available to resolve
12117 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12118 TREE_OPERAND (expr, 0) : expr);
12119 if (TREE_CODE (inner_expr) == OVERLOAD
12120 || TREE_CODE (inner_expr) == FUNCTION_DECL
12121 || TREE_CODE (inner_expr) == TEMPLATE_DECL
12122 || TREE_CODE (inner_expr) == TEMPLATE_ID_EXPR)
12124 /* Preserve string constants; conversions from string constants to
12125 "char *" are allowed, even though normally a "const char *"
12126 cannot be used to initialize a "char *". */
12127 if (TREE_CODE (expr) == STRING_CST)
12129 /* Preserve arithmetic constants, as an optimization -- there is no
12130 reason to create a new node. */
12131 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12133 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12134 There is at least one place where we want to know that a
12135 particular expression is a throw-expression: when checking a ?:
12136 expression, there are special rules if the second or third
12137 argument is a throw-expression. */
12138 if (TREE_CODE (expr) == THROW_EXPR)
12141 if (TREE_CODE (expr) == COND_EXPR)
12142 return build (COND_EXPR,
12144 TREE_OPERAND (expr, 0),
12145 (TREE_OPERAND (expr, 1)
12146 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12147 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12148 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12149 if (TREE_CODE (expr) == COMPOUND_EXPR
12150 && !COMPOUND_EXPR_OVERLOADED (expr))
12151 return build (COMPOUND_EXPR,
12153 TREE_OPERAND (expr, 0),
12154 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12156 /* Otherwise, build a NON_DEPENDENT_EXPR.
12158 REFERENCE_TYPEs are not stripped for expressions in templates
12159 because doing so would play havoc with mangling. Consider, for
12162 template <typename T> void f<T& g>() { g(); }
12164 In the body of "f", the expression for "g" will have
12165 REFERENCE_TYPE, even though the standard says that it should
12166 not. The reason is that we must preserve the syntactic form of
12167 the expression so that mangling (say) "f<g>" inside the body of
12168 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12170 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12173 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12174 Return a new TREE_LIST with the various arguments replaced with
12175 equivalent non-dependent expressions. */
12178 build_non_dependent_args (tree args)
12183 new_args = NULL_TREE;
12184 for (a = args; a; a = TREE_CHAIN (a))
12185 new_args = tree_cons (NULL_TREE,
12186 build_non_dependent_expr (TREE_VALUE (a)),
12188 return nreverse (new_args);
12191 #include "gt-cp-pt.h"