1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987-2017 Free Software Foundation, Inc.
3 Contributed by Michael Tiemann (tiemann@cygnus.com)
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
22 /* High-level class interface. */
26 #include "coretypes.h"
29 #include "stringpool.h"
31 #include "stor-layout.h"
41 /* Id for dumping the class hierarchy. */
44 /* The number of nested classes being processed. If we are not in the
45 scope of any class, this is zero. */
47 int current_class_depth
;
49 /* In order to deal with nested classes, we keep a stack of classes.
50 The topmost entry is the innermost class, and is the entry at index
51 CURRENT_CLASS_DEPTH */
53 typedef struct class_stack_node
{
54 /* The name of the class. */
57 /* The _TYPE node for the class. */
60 /* The access specifier pending for new declarations in the scope of
64 /* If were defining TYPE, the names used in this class. */
65 splay_tree names_used
;
67 /* Nonzero if this class is no longer open, because of a call to
70 }* class_stack_node_t
;
74 /* The base for which we're building initializers. */
76 /* The type of the most-derived type. */
78 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
79 unless ctor_vtbl_p is true. */
81 /* The negative-index vtable initializers built up so far. These
82 are in order from least negative index to most negative index. */
83 vec
<constructor_elt
, va_gc
> *inits
;
84 /* The binfo for the virtual base for which we're building
85 vcall offset initializers. */
87 /* The functions in vbase for which we have already provided vcall
89 vec
<tree
, va_gc
> *fns
;
90 /* The vtable index of the next vcall or vbase offset. */
92 /* Nonzero if we are building the initializer for the primary
95 /* Nonzero if we are building the initializer for a construction
98 /* True when adding vcall offset entries to the vtable. False when
99 merely computing the indices. */
100 bool generate_vcall_entries
;
103 /* The type of a function passed to walk_subobject_offsets. */
104 typedef int (*subobject_offset_fn
) (tree
, tree
, splay_tree
);
106 /* The stack itself. This is a dynamically resized array. The
107 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
108 static int current_class_stack_size
;
109 static class_stack_node_t current_class_stack
;
111 /* The size of the largest empty class seen in this translation unit. */
112 static GTY (()) tree sizeof_biggest_empty_class
;
114 /* An array of all local classes present in this translation unit, in
115 declaration order. */
116 vec
<tree
, va_gc
> *local_classes
;
118 static tree
get_vfield_name (tree
);
119 static void finish_struct_anon (tree
);
120 static tree
get_vtable_name (tree
);
121 static void get_basefndecls (tree
, tree
, vec
<tree
> *);
122 static int build_primary_vtable (tree
, tree
);
123 static int build_secondary_vtable (tree
);
124 static void finish_vtbls (tree
);
125 static void modify_vtable_entry (tree
, tree
, tree
, tree
, tree
*);
126 static void finish_struct_bits (tree
);
127 static int alter_access (tree
, tree
, tree
);
128 static void handle_using_decl (tree
, tree
);
129 static tree
dfs_modify_vtables (tree
, void *);
130 static tree
modify_all_vtables (tree
, tree
);
131 static void determine_primary_bases (tree
);
132 static void maybe_warn_about_overly_private_class (tree
);
133 static void add_implicitly_declared_members (tree
, tree
*, int, int);
134 static tree
fixed_type_or_null (tree
, int *, int *);
135 static tree
build_simple_base_path (tree expr
, tree binfo
);
136 static tree
build_vtbl_ref_1 (tree
, tree
);
137 static void build_vtbl_initializer (tree
, tree
, tree
, tree
, int *,
138 vec
<constructor_elt
, va_gc
> **);
139 static bool check_bitfield_decl (tree
);
140 static bool check_field_decl (tree
, tree
, int *, int *);
141 static void check_field_decls (tree
, tree
*, int *, int *);
142 static tree
*build_base_field (record_layout_info
, tree
, splay_tree
, tree
*);
143 static void build_base_fields (record_layout_info
, splay_tree
, tree
*);
144 static void check_methods (tree
);
145 static void remove_zero_width_bit_fields (tree
);
146 static bool accessible_nvdtor_p (tree
);
148 /* Used by find_flexarrays and related functions. */
150 static void diagnose_flexarrays (tree
, const flexmems_t
*);
151 static void find_flexarrays (tree
, flexmems_t
*, bool = false,
152 tree
= NULL_TREE
, tree
= NULL_TREE
);
153 static void check_flexarrays (tree
, flexmems_t
* = NULL
, bool = false);
154 static void check_bases (tree
, int *, int *);
155 static void check_bases_and_members (tree
);
156 static tree
create_vtable_ptr (tree
, tree
*);
157 static void include_empty_classes (record_layout_info
);
158 static void layout_class_type (tree
, tree
*);
159 static void propagate_binfo_offsets (tree
, tree
);
160 static void layout_virtual_bases (record_layout_info
, splay_tree
);
161 static void build_vbase_offset_vtbl_entries (tree
, vtbl_init_data
*);
162 static void add_vcall_offset_vtbl_entries_r (tree
, vtbl_init_data
*);
163 static void add_vcall_offset_vtbl_entries_1 (tree
, vtbl_init_data
*);
164 static void build_vcall_offset_vtbl_entries (tree
, vtbl_init_data
*);
165 static void add_vcall_offset (tree
, tree
, vtbl_init_data
*);
166 static void layout_vtable_decl (tree
, int);
167 static tree
dfs_find_final_overrider_pre (tree
, void *);
168 static tree
dfs_find_final_overrider_post (tree
, void *);
169 static tree
find_final_overrider (tree
, tree
, tree
);
170 static int make_new_vtable (tree
, tree
);
171 static tree
get_primary_binfo (tree
);
172 static int maybe_indent_hierarchy (FILE *, int, int);
173 static tree
dump_class_hierarchy_r (FILE *, dump_flags_t
, tree
, tree
, int);
174 static void dump_class_hierarchy (tree
);
175 static void dump_class_hierarchy_1 (FILE *, dump_flags_t
, tree
);
176 static void dump_array (FILE *, tree
);
177 static void dump_vtable (tree
, tree
, tree
);
178 static void dump_vtt (tree
, tree
);
179 static void dump_thunk (FILE *, int, tree
);
180 static tree
build_vtable (tree
, tree
, tree
);
181 static void initialize_vtable (tree
, vec
<constructor_elt
, va_gc
> *);
182 static void layout_nonempty_base_or_field (record_layout_info
,
183 tree
, tree
, splay_tree
);
184 static tree
end_of_class (tree
, int);
185 static bool layout_empty_base (record_layout_info
, tree
, tree
, splay_tree
);
186 static void accumulate_vtbl_inits (tree
, tree
, tree
, tree
, tree
,
187 vec
<constructor_elt
, va_gc
> **);
188 static void dfs_accumulate_vtbl_inits (tree
, tree
, tree
, tree
, tree
,
189 vec
<constructor_elt
, va_gc
> **);
190 static void build_rtti_vtbl_entries (tree
, vtbl_init_data
*);
191 static void build_vcall_and_vbase_vtbl_entries (tree
, vtbl_init_data
*);
192 static void clone_constructors_and_destructors (tree
);
193 static tree
build_clone (tree
, tree
);
194 static void update_vtable_entry_for_fn (tree
, tree
, tree
, tree
*, unsigned);
195 static void build_ctor_vtbl_group (tree
, tree
);
196 static void build_vtt (tree
);
197 static tree
binfo_ctor_vtable (tree
);
198 static void build_vtt_inits (tree
, tree
, vec
<constructor_elt
, va_gc
> **,
200 static tree
dfs_build_secondary_vptr_vtt_inits (tree
, void *);
201 static tree
dfs_fixup_binfo_vtbls (tree
, void *);
202 static int record_subobject_offset (tree
, tree
, splay_tree
);
203 static int check_subobject_offset (tree
, tree
, splay_tree
);
204 static int walk_subobject_offsets (tree
, subobject_offset_fn
,
205 tree
, splay_tree
, tree
, int);
206 static void record_subobject_offsets (tree
, tree
, splay_tree
, bool);
207 static int layout_conflict_p (tree
, tree
, splay_tree
, int);
208 static int splay_tree_compare_integer_csts (splay_tree_key k1
,
210 static void warn_about_ambiguous_bases (tree
);
211 static bool type_requires_array_cookie (tree
);
212 static bool base_derived_from (tree
, tree
);
213 static int empty_base_at_nonzero_offset_p (tree
, tree
, splay_tree
);
214 static tree
end_of_base (tree
);
215 static tree
get_vcall_index (tree
, tree
);
216 static bool type_maybe_constexpr_default_constructor (tree
);
218 /* Variables shared between class.c and call.c. */
221 int n_vtable_entries
= 0;
222 int n_vtable_searches
= 0;
223 int n_vtable_elems
= 0;
224 int n_convert_harshness
= 0;
225 int n_compute_conversion_costs
= 0;
226 int n_inner_fields_searched
= 0;
228 /* Return a COND_EXPR that executes TRUE_STMT if this execution of the
229 'structor is in charge of 'structing virtual bases, or FALSE_STMT
233 build_if_in_charge (tree true_stmt
, tree false_stmt
)
235 gcc_assert (DECL_HAS_IN_CHARGE_PARM_P (current_function_decl
));
236 tree cmp
= build2 (NE_EXPR
, boolean_type_node
,
237 current_in_charge_parm
, integer_zero_node
);
238 tree type
= unlowered_expr_type (true_stmt
);
239 if (VOID_TYPE_P (type
))
240 type
= unlowered_expr_type (false_stmt
);
241 tree cond
= build3 (COND_EXPR
, type
,
242 cmp
, true_stmt
, false_stmt
);
246 /* Convert to or from a base subobject. EXPR is an expression of type
247 `A' or `A*', an expression of type `B' or `B*' is returned. To
248 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
249 the B base instance within A. To convert base A to derived B, CODE
250 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
251 In this latter case, A must not be a morally virtual base of B.
252 NONNULL is true if EXPR is known to be non-NULL (this is only
253 needed when EXPR is of pointer type). CV qualifiers are preserved
257 build_base_path (enum tree_code code
,
261 tsubst_flags_t complain
)
263 tree v_binfo
= NULL_TREE
;
264 tree d_binfo
= NULL_TREE
;
268 tree null_test
= NULL
;
269 tree ptr_target_type
;
271 int want_pointer
= TYPE_PTR_P (TREE_TYPE (expr
));
272 bool has_empty
= false;
276 if (expr
== error_mark_node
|| binfo
== error_mark_node
|| !binfo
)
277 return error_mark_node
;
279 for (probe
= binfo
; probe
; probe
= BINFO_INHERITANCE_CHAIN (probe
))
282 if (is_empty_class (BINFO_TYPE (probe
)))
284 if (!v_binfo
&& BINFO_VIRTUAL_P (probe
))
288 probe
= TYPE_MAIN_VARIANT (TREE_TYPE (expr
));
290 probe
= TYPE_MAIN_VARIANT (TREE_TYPE (probe
));
292 if (code
== PLUS_EXPR
293 && !SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo
), probe
))
295 /* This can happen when adjust_result_of_qualified_name_lookup can't
296 find a unique base binfo in a call to a member function. We
297 couldn't give the diagnostic then since we might have been calling
298 a static member function, so we do it now. In other cases, eg.
299 during error recovery (c++/71979), we may not have a base at all. */
300 if (complain
& tf_error
)
302 tree base
= lookup_base (probe
, BINFO_TYPE (d_binfo
),
303 ba_unique
, NULL
, complain
);
304 gcc_assert (base
== error_mark_node
|| !base
);
306 return error_mark_node
;
309 gcc_assert ((code
== MINUS_EXPR
310 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), probe
))
311 || code
== PLUS_EXPR
);
313 if (binfo
== d_binfo
)
317 if (code
== MINUS_EXPR
&& v_binfo
)
319 if (complain
& tf_error
)
321 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), BINFO_TYPE (v_binfo
)))
324 error ("cannot convert from pointer to base class %qT to "
325 "pointer to derived class %qT because the base is "
326 "virtual", BINFO_TYPE (binfo
), BINFO_TYPE (d_binfo
));
328 error ("cannot convert from base class %qT to derived "
329 "class %qT because the base is virtual",
330 BINFO_TYPE (binfo
), BINFO_TYPE (d_binfo
));
335 error ("cannot convert from pointer to base class %qT to "
336 "pointer to derived class %qT via virtual base %qT",
337 BINFO_TYPE (binfo
), BINFO_TYPE (d_binfo
),
338 BINFO_TYPE (v_binfo
));
340 error ("cannot convert from base class %qT to derived "
341 "class %qT via virtual base %qT", BINFO_TYPE (binfo
),
342 BINFO_TYPE (d_binfo
), BINFO_TYPE (v_binfo
));
345 return error_mark_node
;
350 rvalue
= !lvalue_p (expr
);
351 /* This must happen before the call to save_expr. */
352 expr
= cp_build_addr_expr (expr
, complain
);
355 expr
= mark_rvalue_use (expr
);
357 offset
= BINFO_OFFSET (binfo
);
358 fixed_type_p
= resolves_to_fixed_type_p (expr
, &nonnull
);
359 target_type
= code
== PLUS_EXPR
? BINFO_TYPE (binfo
) : BINFO_TYPE (d_binfo
);
360 /* TARGET_TYPE has been extracted from BINFO, and, is therefore always
361 cv-unqualified. Extract the cv-qualifiers from EXPR so that the
362 expression returned matches the input. */
363 target_type
= cp_build_qualified_type
364 (target_type
, cp_type_quals (TREE_TYPE (TREE_TYPE (expr
))));
365 ptr_target_type
= build_pointer_type (target_type
);
367 /* Do we need to look in the vtable for the real offset? */
368 virtual_access
= (v_binfo
&& fixed_type_p
<= 0);
370 /* Don't bother with the calculations inside sizeof; they'll ICE if the
371 source type is incomplete and the pointer value doesn't matter. In a
372 template (even in instantiate_non_dependent_expr), we don't have vtables
373 set up properly yet, and the value doesn't matter there either; we're
374 just interested in the result of overload resolution. */
375 if (cp_unevaluated_operand
!= 0
376 || processing_template_decl
377 || in_template_function ())
379 expr
= build_nop (ptr_target_type
, expr
);
383 /* If we're in an NSDMI, we don't have the full constructor context yet
384 that we need for converting to a virtual base, so just build a stub
385 CONVERT_EXPR and expand it later in bot_replace. */
386 if (virtual_access
&& fixed_type_p
< 0
387 && current_scope () != current_function_decl
)
389 expr
= build1 (CONVERT_EXPR
, ptr_target_type
, expr
);
390 CONVERT_EXPR_VBASE_PATH (expr
) = true;
394 /* Do we need to check for a null pointer? */
395 if (want_pointer
&& !nonnull
)
397 /* If we know the conversion will not actually change the value
398 of EXPR, then we can avoid testing the expression for NULL.
399 We have to avoid generating a COMPONENT_REF for a base class
400 field, because other parts of the compiler know that such
401 expressions are always non-NULL. */
402 if (!virtual_access
&& integer_zerop (offset
))
403 return build_nop (ptr_target_type
, expr
);
404 null_test
= error_mark_node
;
407 /* Protect against multiple evaluation if necessary. */
408 if (TREE_SIDE_EFFECTS (expr
) && (null_test
|| virtual_access
))
409 expr
= save_expr (expr
);
411 /* Now that we've saved expr, build the real null test. */
414 tree zero
= cp_convert (TREE_TYPE (expr
), nullptr_node
, complain
);
415 null_test
= build2_loc (input_location
, NE_EXPR
, boolean_type_node
,
417 /* This is a compiler generated comparison, don't emit
418 e.g. -Wnonnull-compare warning for it. */
419 TREE_NO_WARNING (null_test
) = 1;
422 /* If this is a simple base reference, express it as a COMPONENT_REF. */
423 if (code
== PLUS_EXPR
&& !virtual_access
424 /* We don't build base fields for empty bases, and they aren't very
425 interesting to the optimizers anyway. */
428 expr
= cp_build_indirect_ref (expr
, RO_NULL
, complain
);
429 expr
= build_simple_base_path (expr
, binfo
);
433 expr
= build_address (expr
);
434 target_type
= TREE_TYPE (expr
);
440 /* Going via virtual base V_BINFO. We need the static offset
441 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
442 V_BINFO. That offset is an entry in D_BINFO's vtable. */
445 if (fixed_type_p
< 0 && in_base_initializer
)
447 /* In a base member initializer, we cannot rely on the
448 vtable being set up. We have to indirect via the
452 t
= TREE_TYPE (TYPE_VFIELD (current_class_type
));
453 t
= build_pointer_type (t
);
454 v_offset
= fold_convert (t
, current_vtt_parm
);
455 v_offset
= cp_build_indirect_ref (v_offset
, RO_NULL
, complain
);
460 if (sanitize_flags_p (SANITIZE_VPTR
)
461 && fixed_type_p
== 0)
463 t
= cp_ubsan_maybe_instrument_cast_to_vbase (input_location
,
468 v_offset
= build_vfield_ref (cp_build_indirect_ref (t
, RO_NULL
,
470 TREE_TYPE (TREE_TYPE (expr
)));
473 if (v_offset
== error_mark_node
)
474 return error_mark_node
;
476 v_offset
= fold_build_pointer_plus (v_offset
, BINFO_VPTR_FIELD (v_binfo
));
477 v_offset
= build1 (NOP_EXPR
,
478 build_pointer_type (ptrdiff_type_node
),
480 v_offset
= cp_build_indirect_ref (v_offset
, RO_NULL
, complain
);
481 TREE_CONSTANT (v_offset
) = 1;
483 offset
= convert_to_integer (ptrdiff_type_node
,
484 size_diffop_loc (input_location
, offset
,
485 BINFO_OFFSET (v_binfo
)));
487 if (!integer_zerop (offset
))
488 v_offset
= build2 (code
, ptrdiff_type_node
, v_offset
, offset
);
490 if (fixed_type_p
< 0)
491 /* Negative fixed_type_p means this is a constructor or destructor;
492 virtual base layout is fixed in in-charge [cd]tors, but not in
494 offset
= build_if_in_charge
495 (convert_to_integer (ptrdiff_type_node
, BINFO_OFFSET (binfo
)),
502 target_type
= ptr_target_type
;
504 expr
= build1 (NOP_EXPR
, ptr_target_type
, expr
);
506 if (!integer_zerop (offset
))
508 offset
= fold_convert (sizetype
, offset
);
509 if (code
== MINUS_EXPR
)
510 offset
= fold_build1_loc (input_location
, NEGATE_EXPR
, sizetype
, offset
);
511 expr
= fold_build_pointer_plus (expr
, offset
);
519 expr
= cp_build_indirect_ref (expr
, RO_NULL
, complain
);
526 expr
= fold_build3_loc (input_location
, COND_EXPR
, target_type
, null_test
, expr
,
527 build_zero_cst (target_type
));
532 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
533 Perform a derived-to-base conversion by recursively building up a
534 sequence of COMPONENT_REFs to the appropriate base fields. */
537 build_simple_base_path (tree expr
, tree binfo
)
539 tree type
= BINFO_TYPE (binfo
);
540 tree d_binfo
= BINFO_INHERITANCE_CHAIN (binfo
);
543 if (d_binfo
== NULL_TREE
)
547 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr
)) == type
);
549 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
550 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
551 an lvalue in the front end; only _DECLs and _REFs are lvalues
553 temp
= unary_complex_lvalue (ADDR_EXPR
, expr
);
555 expr
= cp_build_indirect_ref (temp
, RO_NULL
, tf_warning_or_error
);
561 expr
= build_simple_base_path (expr
, d_binfo
);
563 for (field
= TYPE_FIELDS (BINFO_TYPE (d_binfo
));
564 field
; field
= DECL_CHAIN (field
))
565 /* Is this the base field created by build_base_field? */
566 if (TREE_CODE (field
) == FIELD_DECL
567 && DECL_FIELD_IS_BASE (field
)
568 && TREE_TYPE (field
) == type
569 /* If we're looking for a field in the most-derived class,
570 also check the field offset; we can have two base fields
571 of the same type if one is an indirect virtual base and one
572 is a direct non-virtual base. */
573 && (BINFO_INHERITANCE_CHAIN (d_binfo
)
574 || tree_int_cst_equal (byte_position (field
),
575 BINFO_OFFSET (binfo
))))
577 /* We don't use build_class_member_access_expr here, as that
578 has unnecessary checks, and more importantly results in
579 recursive calls to dfs_walk_once. */
580 int type_quals
= cp_type_quals (TREE_TYPE (expr
));
582 expr
= build3 (COMPONENT_REF
,
583 cp_build_qualified_type (type
, type_quals
),
584 expr
, field
, NULL_TREE
);
585 /* Mark the expression const or volatile, as appropriate.
586 Even though we've dealt with the type above, we still have
587 to mark the expression itself. */
588 if (type_quals
& TYPE_QUAL_CONST
)
589 TREE_READONLY (expr
) = 1;
590 if (type_quals
& TYPE_QUAL_VOLATILE
)
591 TREE_THIS_VOLATILE (expr
) = 1;
596 /* Didn't find the base field?!? */
600 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
601 type is a class type or a pointer to a class type. In the former
602 case, TYPE is also a class type; in the latter it is another
603 pointer type. If CHECK_ACCESS is true, an error message is emitted
604 if TYPE is inaccessible. If OBJECT has pointer type, the value is
605 assumed to be non-NULL. */
608 convert_to_base (tree object
, tree type
, bool check_access
, bool nonnull
,
609 tsubst_flags_t complain
)
614 if (TYPE_PTR_P (TREE_TYPE (object
)))
616 object_type
= TREE_TYPE (TREE_TYPE (object
));
617 type
= TREE_TYPE (type
);
620 object_type
= TREE_TYPE (object
);
622 binfo
= lookup_base (object_type
, type
, check_access
? ba_check
: ba_unique
,
624 if (!binfo
|| binfo
== error_mark_node
)
625 return error_mark_node
;
627 return build_base_path (PLUS_EXPR
, object
, binfo
, nonnull
, complain
);
630 /* EXPR is an expression with unqualified class type. BASE is a base
631 binfo of that class type. Returns EXPR, converted to the BASE
632 type. This function assumes that EXPR is the most derived class;
633 therefore virtual bases can be found at their static offsets. */
636 convert_to_base_statically (tree expr
, tree base
)
640 expr_type
= TREE_TYPE (expr
);
641 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base
), expr_type
))
643 /* If this is a non-empty base, use a COMPONENT_REF. */
644 if (!is_empty_class (BINFO_TYPE (base
)))
645 return build_simple_base_path (expr
, base
);
647 /* We use fold_build2 and fold_convert below to simplify the trees
648 provided to the optimizers. It is not safe to call these functions
649 when processing a template because they do not handle C++-specific
651 gcc_assert (!processing_template_decl
);
652 expr
= cp_build_addr_expr (expr
, tf_warning_or_error
);
653 if (!integer_zerop (BINFO_OFFSET (base
)))
654 expr
= fold_build_pointer_plus_loc (input_location
,
655 expr
, BINFO_OFFSET (base
));
656 expr
= fold_convert (build_pointer_type (BINFO_TYPE (base
)), expr
);
657 expr
= build_fold_indirect_ref_loc (input_location
, expr
);
665 build_vfield_ref (tree datum
, tree type
)
667 tree vfield
, vcontext
;
669 if (datum
== error_mark_node
670 /* Can happen in case of duplicate base types (c++/59082). */
671 || !TYPE_VFIELD (type
))
672 return error_mark_node
;
674 /* First, convert to the requested type. */
675 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum
), type
))
676 datum
= convert_to_base (datum
, type
, /*check_access=*/false,
677 /*nonnull=*/true, tf_warning_or_error
);
679 /* Second, the requested type may not be the owner of its own vptr.
680 If not, convert to the base class that owns it. We cannot use
681 convert_to_base here, because VCONTEXT may appear more than once
682 in the inheritance hierarchy of TYPE, and thus direct conversion
683 between the types may be ambiguous. Following the path back up
684 one step at a time via primary bases avoids the problem. */
685 vfield
= TYPE_VFIELD (type
);
686 vcontext
= DECL_CONTEXT (vfield
);
687 while (!same_type_ignoring_top_level_qualifiers_p (vcontext
, type
))
689 datum
= build_simple_base_path (datum
, CLASSTYPE_PRIMARY_BINFO (type
));
690 type
= TREE_TYPE (datum
);
693 return build3 (COMPONENT_REF
, TREE_TYPE (vfield
), datum
, vfield
, NULL_TREE
);
696 /* Given an object INSTANCE, return an expression which yields the
697 vtable element corresponding to INDEX. There are many special
698 cases for INSTANCE which we take care of here, mainly to avoid
699 creating extra tree nodes when we don't have to. */
702 build_vtbl_ref_1 (tree instance
, tree idx
)
705 tree vtbl
= NULL_TREE
;
707 /* Try to figure out what a reference refers to, and
708 access its virtual function table directly. */
711 tree fixed_type
= fixed_type_or_null (instance
, NULL
, &cdtorp
);
713 tree basetype
= non_reference (TREE_TYPE (instance
));
715 if (fixed_type
&& !cdtorp
)
717 tree binfo
= lookup_base (fixed_type
, basetype
,
718 ba_unique
, NULL
, tf_none
);
719 if (binfo
&& binfo
!= error_mark_node
)
720 vtbl
= unshare_expr (BINFO_VTABLE (binfo
));
724 vtbl
= build_vfield_ref (instance
, basetype
);
726 aref
= build_array_ref (input_location
, vtbl
, idx
);
727 TREE_CONSTANT (aref
) |= TREE_CONSTANT (vtbl
) && TREE_CONSTANT (idx
);
733 build_vtbl_ref (tree instance
, tree idx
)
735 tree aref
= build_vtbl_ref_1 (instance
, idx
);
740 /* Given a stable object pointer INSTANCE_PTR, return an expression which
741 yields a function pointer corresponding to vtable element INDEX. */
744 build_vfn_ref (tree instance_ptr
, tree idx
)
748 aref
= build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr
, RO_NULL
,
749 tf_warning_or_error
),
752 /* When using function descriptors, the address of the
753 vtable entry is treated as a function pointer. */
754 if (TARGET_VTABLE_USES_DESCRIPTORS
)
755 aref
= build1 (NOP_EXPR
, TREE_TYPE (aref
),
756 cp_build_addr_expr (aref
, tf_warning_or_error
));
758 /* Remember this as a method reference, for later devirtualization. */
759 aref
= build3 (OBJ_TYPE_REF
, TREE_TYPE (aref
), aref
, instance_ptr
, idx
);
764 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
765 for the given TYPE. */
768 get_vtable_name (tree type
)
770 return mangle_vtbl_for_type (type
);
773 /* DECL is an entity associated with TYPE, like a virtual table or an
774 implicitly generated constructor. Determine whether or not DECL
775 should have external or internal linkage at the object file
776 level. This routine does not deal with COMDAT linkage and other
777 similar complexities; it simply sets TREE_PUBLIC if it possible for
778 entities in other translation units to contain copies of DECL, in
782 set_linkage_according_to_type (tree
/*type*/, tree decl
)
784 TREE_PUBLIC (decl
) = 1;
785 determine_visibility (decl
);
788 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
789 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
790 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
793 build_vtable (tree class_type
, tree name
, tree vtable_type
)
797 decl
= build_lang_decl (VAR_DECL
, name
, vtable_type
);
798 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
799 now to avoid confusion in mangle_decl. */
800 SET_DECL_ASSEMBLER_NAME (decl
, name
);
801 DECL_CONTEXT (decl
) = class_type
;
802 DECL_ARTIFICIAL (decl
) = 1;
803 TREE_STATIC (decl
) = 1;
804 TREE_READONLY (decl
) = 1;
805 DECL_VIRTUAL_P (decl
) = 1;
806 SET_DECL_ALIGN (decl
, TARGET_VTABLE_ENTRY_ALIGN
);
807 DECL_USER_ALIGN (decl
) = true;
808 DECL_VTABLE_OR_VTT_P (decl
) = 1;
809 set_linkage_according_to_type (class_type
, decl
);
810 /* The vtable has not been defined -- yet. */
811 DECL_EXTERNAL (decl
) = 1;
812 DECL_NOT_REALLY_EXTERN (decl
) = 1;
814 /* Mark the VAR_DECL node representing the vtable itself as a
815 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
816 is rather important that such things be ignored because any
817 effort to actually generate DWARF for them will run into
818 trouble when/if we encounter code like:
821 struct S { virtual void member (); };
823 because the artificial declaration of the vtable itself (as
824 manufactured by the g++ front end) will say that the vtable is
825 a static member of `S' but only *after* the debug output for
826 the definition of `S' has already been output. This causes
827 grief because the DWARF entry for the definition of the vtable
828 will try to refer back to an earlier *declaration* of the
829 vtable as a static member of `S' and there won't be one. We
830 might be able to arrange to have the "vtable static member"
831 attached to the member list for `S' before the debug info for
832 `S' get written (which would solve the problem) but that would
833 require more intrusive changes to the g++ front end. */
834 DECL_IGNORED_P (decl
) = 1;
839 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
840 or even complete. If this does not exist, create it. If COMPLETE is
841 nonzero, then complete the definition of it -- that will render it
842 impossible to actually build the vtable, but is useful to get at those
843 which are known to exist in the runtime. */
846 get_vtable_decl (tree type
, int complete
)
850 if (CLASSTYPE_VTABLES (type
))
851 return CLASSTYPE_VTABLES (type
);
853 decl
= build_vtable (type
, get_vtable_name (type
), vtbl_type_node
);
854 CLASSTYPE_VTABLES (type
) = decl
;
858 DECL_EXTERNAL (decl
) = 1;
859 cp_finish_decl (decl
, NULL_TREE
, false, NULL_TREE
, 0);
865 /* Build the primary virtual function table for TYPE. If BINFO is
866 non-NULL, build the vtable starting with the initial approximation
867 that it is the same as the one which is the head of the association
868 list. Returns a nonzero value if a new vtable is actually
872 build_primary_vtable (tree binfo
, tree type
)
877 decl
= get_vtable_decl (type
, /*complete=*/0);
881 if (BINFO_NEW_VTABLE_MARKED (binfo
))
882 /* We have already created a vtable for this base, so there's
883 no need to do it again. */
886 virtuals
= copy_list (BINFO_VIRTUALS (binfo
));
887 TREE_TYPE (decl
) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo
));
888 DECL_SIZE (decl
) = TYPE_SIZE (TREE_TYPE (decl
));
889 DECL_SIZE_UNIT (decl
) = TYPE_SIZE_UNIT (TREE_TYPE (decl
));
893 gcc_assert (TREE_TYPE (decl
) == vtbl_type_node
);
894 virtuals
= NULL_TREE
;
897 if (GATHER_STATISTICS
)
900 n_vtable_elems
+= list_length (virtuals
);
903 /* Initialize the association list for this type, based
904 on our first approximation. */
905 BINFO_VTABLE (TYPE_BINFO (type
)) = decl
;
906 BINFO_VIRTUALS (TYPE_BINFO (type
)) = virtuals
;
907 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type
));
911 /* Give BINFO a new virtual function table which is initialized
912 with a skeleton-copy of its original initialization. The only
913 entry that changes is the `delta' entry, so we can really
914 share a lot of structure.
916 FOR_TYPE is the most derived type which caused this table to
919 Returns nonzero if we haven't met BINFO before.
921 The order in which vtables are built (by calling this function) for
922 an object must remain the same, otherwise a binary incompatibility
926 build_secondary_vtable (tree binfo
)
928 if (BINFO_NEW_VTABLE_MARKED (binfo
))
929 /* We already created a vtable for this base. There's no need to
933 /* Remember that we've created a vtable for this BINFO, so that we
934 don't try to do so again. */
935 SET_BINFO_NEW_VTABLE_MARKED (binfo
);
937 /* Make fresh virtual list, so we can smash it later. */
938 BINFO_VIRTUALS (binfo
) = copy_list (BINFO_VIRTUALS (binfo
));
940 /* Secondary vtables are laid out as part of the same structure as
941 the primary vtable. */
942 BINFO_VTABLE (binfo
) = NULL_TREE
;
946 /* Create a new vtable for BINFO which is the hierarchy dominated by
947 T. Return nonzero if we actually created a new vtable. */
950 make_new_vtable (tree t
, tree binfo
)
952 if (binfo
== TYPE_BINFO (t
))
953 /* In this case, it is *type*'s vtable we are modifying. We start
954 with the approximation that its vtable is that of the
955 immediate base class. */
956 return build_primary_vtable (binfo
, t
);
958 /* This is our very own copy of `basetype' to play with. Later,
959 we will fill in all the virtual functions that override the
960 virtual functions in these base classes which are not defined
961 by the current type. */
962 return build_secondary_vtable (binfo
);
965 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
966 (which is in the hierarchy dominated by T) list FNDECL as its
967 BV_FN. DELTA is the required constant adjustment from the `this'
968 pointer where the vtable entry appears to the `this' required when
969 the function is actually called. */
972 modify_vtable_entry (tree t
,
982 if (fndecl
!= BV_FN (v
)
983 || !tree_int_cst_equal (delta
, BV_DELTA (v
)))
985 /* We need a new vtable for BINFO. */
986 if (make_new_vtable (t
, binfo
))
988 /* If we really did make a new vtable, we also made a copy
989 of the BINFO_VIRTUALS list. Now, we have to find the
990 corresponding entry in that list. */
991 *virtuals
= BINFO_VIRTUALS (binfo
);
992 while (BV_FN (*virtuals
) != BV_FN (v
))
993 *virtuals
= TREE_CHAIN (*virtuals
);
997 BV_DELTA (v
) = delta
;
998 BV_VCALL_INDEX (v
) = NULL_TREE
;
1004 /* Add method METHOD to class TYPE. If VIA_USING indicates whether
1005 METHOD is being injected via a using_decl. Returns true if the
1006 method could be added to the method vec. */
1009 add_method (tree type
, tree method
, bool via_using
)
1011 if (method
== error_mark_node
)
1014 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
1015 grok_special_member_properties (method
);
1017 tree
*slot
= get_member_slot (type
, DECL_NAME (method
));
1018 tree current_fns
= *slot
;
1020 gcc_assert (!DECL_EXTERN_C_P (method
));
1022 /* Check to see if we've already got this method. */
1023 for (ovl_iterator
iter (current_fns
); iter
; ++iter
)
1031 if (TREE_CODE (fn
) != TREE_CODE (method
))
1034 /* Two using-declarations can coexist, we'll complain about ambiguity in
1035 overload resolution. */
1036 if (via_using
&& iter
.using_p ()
1037 /* Except handle inherited constructors specially. */
1038 && ! DECL_CONSTRUCTOR_P (fn
))
1041 /* [over.load] Member function declarations with the
1042 same name and the same parameter types cannot be
1043 overloaded if any of them is a static member
1044 function declaration.
1046 [over.load] Member function declarations with the same name and
1047 the same parameter-type-list as well as member function template
1048 declarations with the same name, the same parameter-type-list, and
1049 the same template parameter lists cannot be overloaded if any of
1050 them, but not all, have a ref-qualifier.
1052 [namespace.udecl] When a using-declaration brings names
1053 from a base class into a derived class scope, member
1054 functions in the derived class override and/or hide member
1055 functions with the same name and parameter types in a base
1056 class (rather than conflicting). */
1057 fn_type
= TREE_TYPE (fn
);
1058 method_type
= TREE_TYPE (method
);
1059 parms1
= TYPE_ARG_TYPES (fn_type
);
1060 parms2
= TYPE_ARG_TYPES (method_type
);
1062 /* Compare the quals on the 'this' parm. Don't compare
1063 the whole types, as used functions are treated as
1064 coming from the using class in overload resolution. */
1065 if (! DECL_STATIC_FUNCTION_P (fn
)
1066 && ! DECL_STATIC_FUNCTION_P (method
)
1067 /* Either both or neither need to be ref-qualified for
1068 differing quals to allow overloading. */
1069 && (FUNCTION_REF_QUALIFIED (fn_type
)
1070 == FUNCTION_REF_QUALIFIED (method_type
))
1071 && (type_memfn_quals (fn_type
) != type_memfn_quals (method_type
)
1072 || type_memfn_rqual (fn_type
) != type_memfn_rqual (method_type
)))
1075 /* For templates, the return type and template parameters
1076 must be identical. */
1077 if (TREE_CODE (fn
) == TEMPLATE_DECL
1078 && (!same_type_p (TREE_TYPE (fn_type
),
1079 TREE_TYPE (method_type
))
1080 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn
),
1081 DECL_TEMPLATE_PARMS (method
))))
1084 if (! DECL_STATIC_FUNCTION_P (fn
))
1085 parms1
= TREE_CHAIN (parms1
);
1086 if (! DECL_STATIC_FUNCTION_P (method
))
1087 parms2
= TREE_CHAIN (parms2
);
1089 /* Bring back parameters omitted from an inherited ctor. */
1090 if (ctor_omit_inherited_parms (fn
))
1091 parms1
= FUNCTION_FIRST_USER_PARMTYPE (DECL_ORIGIN (fn
));
1092 if (ctor_omit_inherited_parms (method
))
1093 parms2
= FUNCTION_FIRST_USER_PARMTYPE (DECL_ORIGIN (method
));
1095 if (compparms (parms1
, parms2
)
1096 && (!DECL_CONV_FN_P (fn
)
1097 || same_type_p (TREE_TYPE (fn_type
),
1098 TREE_TYPE (method_type
)))
1099 && equivalently_constrained (fn
, method
))
1101 /* If these are versions of the same function, process and
1103 if (TREE_CODE (fn
) == FUNCTION_DECL
1104 && maybe_version_functions (method
, fn
))
1107 if (DECL_INHERITED_CTOR (method
))
1109 if (DECL_INHERITED_CTOR (fn
))
1111 tree basem
= DECL_INHERITED_CTOR_BASE (method
);
1112 tree basef
= DECL_INHERITED_CTOR_BASE (fn
);
1113 if (flag_new_inheriting_ctors
)
1117 /* Inheriting the same constructor along different
1118 paths, combine them. */
1119 SET_DECL_INHERITED_CTOR
1120 (fn
, ovl_make (DECL_INHERITED_CTOR (method
),
1121 DECL_INHERITED_CTOR (fn
)));
1122 /* And discard the new one. */
1126 /* Inherited ctors can coexist until overload
1130 error_at (DECL_SOURCE_LOCATION (method
),
1131 "%q#D conflicts with version inherited from %qT",
1133 inform (DECL_SOURCE_LOCATION (fn
),
1134 "version inherited from %qT declared here",
1137 /* Otherwise defer to the other function. */
1142 /* Defer to the local function. */
1144 else if (flag_new_inheriting_ctors
1145 && DECL_INHERITED_CTOR (fn
))
1147 /* Remove the inherited constructor. */
1148 current_fns
= iter
.remove_node (current_fns
);
1153 error_at (DECL_SOURCE_LOCATION (method
),
1154 "%q#D cannot be overloaded with %q#D", method
, fn
);
1155 inform (DECL_SOURCE_LOCATION (fn
),
1156 "previous declaration %q#D", fn
);
1162 /* A class should never have more than one destructor. */
1163 gcc_assert (!current_fns
|| !DECL_DESTRUCTOR_P (method
));
1165 current_fns
= ovl_insert (method
, current_fns
, via_using
);
1167 if (!DECL_CONV_FN_P (method
) && !COMPLETE_TYPE_P (type
))
1168 push_class_level_binding (DECL_NAME (method
), current_fns
);
1170 *slot
= current_fns
;
1175 /* Subroutines of finish_struct. */
1177 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1178 legit, otherwise return 0. */
1181 alter_access (tree t
, tree fdecl
, tree access
)
1185 retrofit_lang_decl (fdecl
);
1187 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl
));
1189 elem
= purpose_member (t
, DECL_ACCESS (fdecl
));
1192 if (TREE_VALUE (elem
) != access
)
1194 if (TREE_CODE (TREE_TYPE (fdecl
)) == FUNCTION_DECL
)
1195 error ("conflicting access specifications for method"
1196 " %q+D, ignored", TREE_TYPE (fdecl
));
1198 error ("conflicting access specifications for field %qE, ignored",
1203 /* They're changing the access to the same thing they changed
1204 it to before. That's OK. */
1210 perform_or_defer_access_check (TYPE_BINFO (t
), fdecl
, fdecl
,
1211 tf_warning_or_error
);
1212 DECL_ACCESS (fdecl
) = tree_cons (t
, access
, DECL_ACCESS (fdecl
));
1218 /* Return the access node for DECL's access in its enclosing class. */
1221 declared_access (tree decl
)
1223 return (TREE_PRIVATE (decl
) ? access_private_node
1224 : TREE_PROTECTED (decl
) ? access_protected_node
1225 : access_public_node
);
1228 /* Process the USING_DECL, which is a member of T. */
1231 handle_using_decl (tree using_decl
, tree t
)
1233 tree decl
= USING_DECL_DECLS (using_decl
);
1234 tree name
= DECL_NAME (using_decl
);
1235 tree access
= declared_access (using_decl
);
1236 tree flist
= NULL_TREE
;
1239 gcc_assert (!processing_template_decl
&& decl
);
1241 old_value
= lookup_member (t
, name
, /*protect=*/0, /*want_type=*/false,
1242 tf_warning_or_error
);
1245 old_value
= OVL_FIRST (old_value
);
1247 if (DECL_P (old_value
) && DECL_CONTEXT (old_value
) == t
)
1250 old_value
= NULL_TREE
;
1253 cp_emit_debug_info_for_using (decl
, t
);
1255 if (is_overloaded_fn (decl
))
1260 else if (is_overloaded_fn (old_value
))
1263 /* It's OK to use functions from a base when there are functions with
1264 the same name already present in the current class. */;
1267 error_at (DECL_SOURCE_LOCATION (using_decl
), "%qD invalid in %q#T "
1268 "because of local method %q#D with same name",
1269 using_decl
, t
, old_value
);
1270 inform (DECL_SOURCE_LOCATION (old_value
),
1271 "local method %q#D declared here", old_value
);
1275 else if (!DECL_ARTIFICIAL (old_value
))
1277 error_at (DECL_SOURCE_LOCATION (using_decl
), "%qD invalid in %q#T "
1278 "because of local member %q#D with same name",
1279 using_decl
, t
, old_value
);
1280 inform (DECL_SOURCE_LOCATION (old_value
),
1281 "local member %q#D declared here", old_value
);
1285 /* Make type T see field decl FDECL with access ACCESS. */
1287 for (ovl_iterator
iter (flist
); iter
; ++iter
)
1289 add_method (t
, *iter
, true);
1290 alter_access (t
, *iter
, access
);
1293 alter_access (t
, decl
, access
);
1296 /* Data structure for find_abi_tags_r, below. */
1300 tree t
; // The type that we're checking for missing tags.
1301 tree subob
; // The subobject of T that we're getting tags from.
1302 tree tags
; // error_mark_node for diagnostics, or a list of missing tags.
1305 /* Subroutine of find_abi_tags_r. Handle a single TAG found on the class TP
1306 in the context of P. TAG can be either an identifier (the DECL_NAME of
1307 a tag NAMESPACE_DECL) or a STRING_CST (a tag attribute). */
1310 check_tag (tree tag
, tree id
, tree
*tp
, abi_tag_data
*p
)
1312 if (!IDENTIFIER_MARKED (id
))
1314 if (p
->tags
!= error_mark_node
)
1316 /* We're collecting tags from template arguments or from
1317 the type of a variable or function return type. */
1318 p
->tags
= tree_cons (NULL_TREE
, tag
, p
->tags
);
1320 /* Don't inherit this tag multiple times. */
1321 IDENTIFIER_MARKED (id
) = true;
1325 /* Tags inherited from type template arguments are only used
1326 to avoid warnings. */
1327 ABI_TAG_IMPLICIT (p
->tags
) = true;
1330 /* For functions and variables we want to warn, too. */
1333 /* Otherwise we're diagnosing missing tags. */
1334 if (TREE_CODE (p
->t
) == FUNCTION_DECL
)
1336 if (warning (OPT_Wabi_tag
, "%qD inherits the %E ABI tag "
1337 "that %qT (used in its return type) has",
1339 inform (location_of (*tp
), "%qT declared here", *tp
);
1341 else if (VAR_P (p
->t
))
1343 if (warning (OPT_Wabi_tag
, "%qD inherits the %E ABI tag "
1344 "that %qT (used in its type) has", p
->t
, tag
, *tp
))
1345 inform (location_of (*tp
), "%qT declared here", *tp
);
1347 else if (TYPE_P (p
->subob
))
1349 if (warning (OPT_Wabi_tag
, "%qT does not have the %E ABI tag "
1350 "that base %qT has", p
->t
, tag
, p
->subob
))
1351 inform (location_of (p
->subob
), "%qT declared here",
1356 if (warning (OPT_Wabi_tag
, "%qT does not have the %E ABI tag "
1357 "that %qT (used in the type of %qD) has",
1358 p
->t
, tag
, *tp
, p
->subob
))
1360 inform (location_of (p
->subob
), "%qD declared here",
1362 inform (location_of (*tp
), "%qT declared here", *tp
);
1368 /* Find all the ABI tags in the attribute list ATTR and either call
1369 check_tag (if TP is non-null) or set IDENTIFIER_MARKED to val. */
1372 mark_or_check_attr_tags (tree attr
, tree
*tp
, abi_tag_data
*p
, bool val
)
1376 for (; (attr
= lookup_attribute ("abi_tag", attr
));
1377 attr
= TREE_CHAIN (attr
))
1378 for (tree list
= TREE_VALUE (attr
); list
;
1379 list
= TREE_CHAIN (list
))
1381 tree tag
= TREE_VALUE (list
);
1382 tree id
= get_identifier (TREE_STRING_POINTER (tag
));
1384 check_tag (tag
, id
, tp
, p
);
1386 IDENTIFIER_MARKED (id
) = val
;
1390 /* Find all the ABI tags on T and its enclosing scopes and either call
1391 check_tag (if TP is non-null) or set IDENTIFIER_MARKED to val. */
1394 mark_or_check_tags (tree t
, tree
*tp
, abi_tag_data
*p
, bool val
)
1396 while (t
!= global_namespace
)
1401 attr
= TYPE_ATTRIBUTES (t
);
1402 t
= CP_TYPE_CONTEXT (t
);
1406 attr
= DECL_ATTRIBUTES (t
);
1407 t
= CP_DECL_CONTEXT (t
);
1409 mark_or_check_attr_tags (attr
, tp
, p
, val
);
1413 /* walk_tree callback for check_abi_tags: if the type at *TP involves any
1414 types with ABI tags, add the corresponding identifiers to the VEC in
1415 *DATA and set IDENTIFIER_MARKED. */
1418 find_abi_tags_r (tree
*tp
, int *walk_subtrees
, void *data
)
1420 if (!OVERLOAD_TYPE_P (*tp
))
1423 /* walk_tree shouldn't be walking into any subtrees of a RECORD_TYPE
1424 anyway, but let's make sure of it. */
1425 *walk_subtrees
= false;
1427 abi_tag_data
*p
= static_cast<struct abi_tag_data
*>(data
);
1429 mark_or_check_tags (*tp
, tp
, p
, false);
1434 /* walk_tree callback for mark_abi_tags: if *TP is a class, set
1435 IDENTIFIER_MARKED on its ABI tags. */
1438 mark_abi_tags_r (tree
*tp
, int *walk_subtrees
, void *data
)
1440 if (!OVERLOAD_TYPE_P (*tp
))
1443 /* walk_tree shouldn't be walking into any subtrees of a RECORD_TYPE
1444 anyway, but let's make sure of it. */
1445 *walk_subtrees
= false;
1447 bool *valp
= static_cast<bool*>(data
);
1449 mark_or_check_tags (*tp
, NULL
, NULL
, *valp
);
1454 /* Set IDENTIFIER_MARKED on all the ABI tags on T and its enclosing
1458 mark_abi_tags (tree t
, bool val
)
1460 mark_or_check_tags (t
, NULL
, NULL
, val
);
1463 if (DECL_LANG_SPECIFIC (t
) && DECL_USE_TEMPLATE (t
)
1464 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t
)))
1466 /* Template arguments are part of the signature. */
1467 tree level
= INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (t
));
1468 for (int j
= 0; j
< TREE_VEC_LENGTH (level
); ++j
)
1470 tree arg
= TREE_VEC_ELT (level
, j
);
1471 cp_walk_tree_without_duplicates (&arg
, mark_abi_tags_r
, &val
);
1474 if (TREE_CODE (t
) == FUNCTION_DECL
)
1475 /* A function's parameter types are part of the signature, so
1476 we don't need to inherit any tags that are also in them. */
1477 for (tree arg
= FUNCTION_FIRST_USER_PARMTYPE (t
); arg
;
1478 arg
= TREE_CHAIN (arg
))
1479 cp_walk_tree_without_duplicates (&TREE_VALUE (arg
),
1480 mark_abi_tags_r
, &val
);
1484 /* Check that T has all the ABI tags that subobject SUBOB has, or
1485 warn if not. If T is a (variable or function) declaration, also
1486 return any missing tags, and add them to T if JUST_CHECKING is false. */
1489 check_abi_tags (tree t
, tree subob
, bool just_checking
= false)
1491 bool inherit
= DECL_P (t
);
1493 if (!inherit
&& !warn_abi_tag
)
1496 tree decl
= TYPE_P (t
) ? TYPE_NAME (t
) : t
;
1497 if (!TREE_PUBLIC (decl
))
1498 /* No need to worry about things local to this TU. */
1501 mark_abi_tags (t
, true);
1503 tree subtype
= TYPE_P (subob
) ? subob
: TREE_TYPE (subob
);
1504 struct abi_tag_data data
= { t
, subob
, error_mark_node
};
1506 data
.tags
= NULL_TREE
;
1508 cp_walk_tree_without_duplicates (&subtype
, find_abi_tags_r
, &data
);
1510 if (!(inherit
&& data
.tags
))
1511 /* We don't need to do anything with data.tags. */;
1512 else if (just_checking
)
1513 for (tree t
= data
.tags
; t
; t
= TREE_CHAIN (t
))
1515 tree id
= get_identifier (TREE_STRING_POINTER (TREE_VALUE (t
)));
1516 IDENTIFIER_MARKED (id
) = false;
1520 tree attr
= lookup_attribute ("abi_tag", DECL_ATTRIBUTES (t
));
1522 TREE_VALUE (attr
) = chainon (data
.tags
, TREE_VALUE (attr
));
1525 = tree_cons (get_identifier ("abi_tag"), data
.tags
,
1526 DECL_ATTRIBUTES (t
));
1529 mark_abi_tags (t
, false);
1534 /* Check that DECL has all the ABI tags that are used in parts of its type
1535 that are not reflected in its mangled name. */
1538 check_abi_tags (tree decl
)
1541 check_abi_tags (decl
, TREE_TYPE (decl
));
1542 else if (TREE_CODE (decl
) == FUNCTION_DECL
1543 && !DECL_CONV_FN_P (decl
)
1544 && !mangle_return_type_p (decl
))
1545 check_abi_tags (decl
, TREE_TYPE (TREE_TYPE (decl
)));
1548 /* Return any ABI tags that are used in parts of the type of DECL
1549 that are not reflected in its mangled name. This function is only
1550 used in backward-compatible mangling for ABI <11. */
1553 missing_abi_tags (tree decl
)
1556 return check_abi_tags (decl
, TREE_TYPE (decl
), true);
1557 else if (TREE_CODE (decl
) == FUNCTION_DECL
1558 /* Don't check DECL_CONV_FN_P here like we do in check_abi_tags, so
1559 that we can use this function for setting need_abi_warning
1560 regardless of the current flag_abi_version. */
1561 && !mangle_return_type_p (decl
))
1562 return check_abi_tags (decl
, TREE_TYPE (TREE_TYPE (decl
)), true);
1568 inherit_targ_abi_tags (tree t
)
1570 if (!CLASS_TYPE_P (t
)
1571 || CLASSTYPE_TEMPLATE_INFO (t
) == NULL_TREE
)
1574 mark_abi_tags (t
, true);
1576 tree args
= CLASSTYPE_TI_ARGS (t
);
1577 struct abi_tag_data data
= { t
, NULL_TREE
, NULL_TREE
};
1578 for (int i
= 0; i
< TMPL_ARGS_DEPTH (args
); ++i
)
1580 tree level
= TMPL_ARGS_LEVEL (args
, i
+1);
1581 for (int j
= 0; j
< TREE_VEC_LENGTH (level
); ++j
)
1583 tree arg
= TREE_VEC_ELT (level
, j
);
1585 cp_walk_tree_without_duplicates (&arg
, find_abi_tags_r
, &data
);
1589 // If we found some tags on our template arguments, add them to our
1590 // abi_tag attribute.
1593 tree attr
= lookup_attribute ("abi_tag", TYPE_ATTRIBUTES (t
));
1595 TREE_VALUE (attr
) = chainon (data
.tags
, TREE_VALUE (attr
));
1598 = tree_cons (get_identifier ("abi_tag"), data
.tags
,
1599 TYPE_ATTRIBUTES (t
));
1602 mark_abi_tags (t
, false);
1605 /* Return true, iff class T has a non-virtual destructor that is
1606 accessible from outside the class heirarchy (i.e. is public, or
1607 there's a suitable friend. */
1610 accessible_nvdtor_p (tree t
)
1612 tree dtor
= CLASSTYPE_DESTRUCTOR (t
);
1614 /* An implicitly declared destructor is always public. And,
1615 if it were virtual, we would have created it by now. */
1619 if (DECL_VINDEX (dtor
))
1620 return false; /* Virtual */
1622 if (!TREE_PRIVATE (dtor
) && !TREE_PROTECTED (dtor
))
1623 return true; /* Public */
1625 if (CLASSTYPE_FRIEND_CLASSES (t
)
1626 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t
)))
1627 return true; /* Has friends */
1632 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1633 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1634 properties of the bases. */
1637 check_bases (tree t
,
1638 int* cant_have_const_ctor_p
,
1639 int* no_const_asn_ref_p
)
1642 bool seen_non_virtual_nearly_empty_base_p
= 0;
1643 int seen_tm_mask
= 0;
1646 tree field
= NULL_TREE
;
1648 if (!CLASSTYPE_NON_STD_LAYOUT (t
))
1649 for (field
= TYPE_FIELDS (t
); field
; field
= DECL_CHAIN (field
))
1650 if (TREE_CODE (field
) == FIELD_DECL
)
1653 for (binfo
= TYPE_BINFO (t
), i
= 0;
1654 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
1656 tree basetype
= TREE_TYPE (base_binfo
);
1658 gcc_assert (COMPLETE_TYPE_P (basetype
));
1660 if (CLASSTYPE_FINAL (basetype
))
1661 error ("cannot derive from %<final%> base %qT in derived type %qT",
1664 /* If any base class is non-literal, so is the derived class. */
1665 if (!CLASSTYPE_LITERAL_P (basetype
))
1666 CLASSTYPE_LITERAL_P (t
) = false;
1668 /* If the base class doesn't have copy constructors or
1669 assignment operators that take const references, then the
1670 derived class cannot have such a member automatically
1672 if (TYPE_HAS_COPY_CTOR (basetype
)
1673 && ! TYPE_HAS_CONST_COPY_CTOR (basetype
))
1674 *cant_have_const_ctor_p
= 1;
1675 if (TYPE_HAS_COPY_ASSIGN (basetype
)
1676 && !TYPE_HAS_CONST_COPY_ASSIGN (basetype
))
1677 *no_const_asn_ref_p
= 1;
1679 if (BINFO_VIRTUAL_P (base_binfo
))
1680 /* A virtual base does not effect nearly emptiness. */
1682 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype
))
1684 if (seen_non_virtual_nearly_empty_base_p
)
1685 /* And if there is more than one nearly empty base, then the
1686 derived class is not nearly empty either. */
1687 CLASSTYPE_NEARLY_EMPTY_P (t
) = 0;
1689 /* Remember we've seen one. */
1690 seen_non_virtual_nearly_empty_base_p
= 1;
1692 else if (!is_empty_class (basetype
))
1693 /* If the base class is not empty or nearly empty, then this
1694 class cannot be nearly empty. */
1695 CLASSTYPE_NEARLY_EMPTY_P (t
) = 0;
1697 /* A lot of properties from the bases also apply to the derived
1699 TYPE_NEEDS_CONSTRUCTING (t
) |= TYPE_NEEDS_CONSTRUCTING (basetype
);
1700 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t
)
1701 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype
);
1702 TYPE_HAS_COMPLEX_COPY_ASSIGN (t
)
1703 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (basetype
)
1704 || !TYPE_HAS_COPY_ASSIGN (basetype
));
1705 TYPE_HAS_COMPLEX_COPY_CTOR (t
) |= (TYPE_HAS_COMPLEX_COPY_CTOR (basetype
)
1706 || !TYPE_HAS_COPY_CTOR (basetype
));
1707 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t
)
1708 |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (basetype
);
1709 TYPE_HAS_COMPLEX_MOVE_CTOR (t
) |= TYPE_HAS_COMPLEX_MOVE_CTOR (basetype
);
1710 TYPE_POLYMORPHIC_P (t
) |= TYPE_POLYMORPHIC_P (basetype
);
1711 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t
)
1712 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype
);
1713 TYPE_HAS_COMPLEX_DFLT (t
) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
1714 || TYPE_HAS_COMPLEX_DFLT (basetype
));
1715 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT
1716 (t
, CLASSTYPE_READONLY_FIELDS_NEED_INIT (t
)
1717 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (basetype
));
1718 SET_CLASSTYPE_REF_FIELDS_NEED_INIT
1719 (t
, CLASSTYPE_REF_FIELDS_NEED_INIT (t
)
1720 | CLASSTYPE_REF_FIELDS_NEED_INIT (basetype
));
1721 if (TYPE_HAS_MUTABLE_P (basetype
))
1722 CLASSTYPE_HAS_MUTABLE (t
) = 1;
1724 /* A standard-layout class is a class that:
1726 * has no non-standard-layout base classes, */
1727 CLASSTYPE_NON_STD_LAYOUT (t
) |= CLASSTYPE_NON_STD_LAYOUT (basetype
);
1728 if (!CLASSTYPE_NON_STD_LAYOUT (t
))
1731 /* ...has no base classes of the same type as the first non-static
1733 if (field
&& DECL_CONTEXT (field
) == t
1734 && (same_type_ignoring_top_level_qualifiers_p
1735 (TREE_TYPE (field
), basetype
)))
1736 CLASSTYPE_NON_STD_LAYOUT (t
) = 1;
1738 /* ...either has no non-static data members in the most-derived
1739 class and at most one base class with non-static data
1740 members, or has no base classes with non-static data
1742 for (basefield
= TYPE_FIELDS (basetype
); basefield
;
1743 basefield
= DECL_CHAIN (basefield
))
1744 if (TREE_CODE (basefield
) == FIELD_DECL
1745 && !(DECL_FIELD_IS_BASE (basefield
)
1746 && integer_zerop (DECL_SIZE (basefield
))))
1749 CLASSTYPE_NON_STD_LAYOUT (t
) = 1;
1756 /* Don't bother collecting tm attributes if transactional memory
1757 support is not enabled. */
1760 tree tm_attr
= find_tm_attribute (TYPE_ATTRIBUTES (basetype
));
1762 seen_tm_mask
|= tm_attr_to_mask (tm_attr
);
1765 check_abi_tags (t
, basetype
);
1768 /* If one of the base classes had TM attributes, and the current class
1769 doesn't define its own, then the current class inherits one. */
1770 if (seen_tm_mask
&& !find_tm_attribute (TYPE_ATTRIBUTES (t
)))
1772 tree tm_attr
= tm_mask_to_attr (least_bit_hwi (seen_tm_mask
));
1773 TYPE_ATTRIBUTES (t
) = tree_cons (tm_attr
, NULL
, TYPE_ATTRIBUTES (t
));
1777 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1778 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1779 that have had a nearly-empty virtual primary base stolen by some
1780 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1784 determine_primary_bases (tree t
)
1787 tree primary
= NULL_TREE
;
1788 tree type_binfo
= TYPE_BINFO (t
);
1791 /* Determine the primary bases of our bases. */
1792 for (base_binfo
= TREE_CHAIN (type_binfo
); base_binfo
;
1793 base_binfo
= TREE_CHAIN (base_binfo
))
1795 tree primary
= CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo
));
1797 /* See if we're the non-virtual primary of our inheritance
1799 if (!BINFO_VIRTUAL_P (base_binfo
))
1801 tree parent
= BINFO_INHERITANCE_CHAIN (base_binfo
);
1802 tree parent_primary
= CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent
));
1805 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo
),
1806 BINFO_TYPE (parent_primary
)))
1807 /* We are the primary binfo. */
1808 BINFO_PRIMARY_P (base_binfo
) = 1;
1810 /* Determine if we have a virtual primary base, and mark it so.
1812 if (primary
&& BINFO_VIRTUAL_P (primary
))
1814 tree this_primary
= copied_binfo (primary
, base_binfo
);
1816 if (BINFO_PRIMARY_P (this_primary
))
1817 /* Someone already claimed this base. */
1818 BINFO_LOST_PRIMARY_P (base_binfo
) = 1;
1823 BINFO_PRIMARY_P (this_primary
) = 1;
1824 BINFO_INHERITANCE_CHAIN (this_primary
) = base_binfo
;
1826 /* A virtual binfo might have been copied from within
1827 another hierarchy. As we're about to use it as a
1828 primary base, make sure the offsets match. */
1829 delta
= size_diffop_loc (input_location
,
1830 fold_convert (ssizetype
,
1831 BINFO_OFFSET (base_binfo
)),
1832 fold_convert (ssizetype
,
1833 BINFO_OFFSET (this_primary
)));
1835 propagate_binfo_offsets (this_primary
, delta
);
1840 /* First look for a dynamic direct non-virtual base. */
1841 for (i
= 0; BINFO_BASE_ITERATE (type_binfo
, i
, base_binfo
); i
++)
1843 tree basetype
= BINFO_TYPE (base_binfo
);
1845 if (TYPE_CONTAINS_VPTR_P (basetype
) && !BINFO_VIRTUAL_P (base_binfo
))
1847 primary
= base_binfo
;
1852 /* A "nearly-empty" virtual base class can be the primary base
1853 class, if no non-virtual polymorphic base can be found. Look for
1854 a nearly-empty virtual dynamic base that is not already a primary
1855 base of something in the hierarchy. If there is no such base,
1856 just pick the first nearly-empty virtual base. */
1858 for (base_binfo
= TREE_CHAIN (type_binfo
); base_binfo
;
1859 base_binfo
= TREE_CHAIN (base_binfo
))
1860 if (BINFO_VIRTUAL_P (base_binfo
)
1861 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo
)))
1863 if (!BINFO_PRIMARY_P (base_binfo
))
1865 /* Found one that is not primary. */
1866 primary
= base_binfo
;
1870 /* Remember the first candidate. */
1871 primary
= base_binfo
;
1875 /* If we've got a primary base, use it. */
1878 tree basetype
= BINFO_TYPE (primary
);
1880 CLASSTYPE_PRIMARY_BINFO (t
) = primary
;
1881 if (BINFO_PRIMARY_P (primary
))
1882 /* We are stealing a primary base. */
1883 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary
)) = 1;
1884 BINFO_PRIMARY_P (primary
) = 1;
1885 if (BINFO_VIRTUAL_P (primary
))
1889 BINFO_INHERITANCE_CHAIN (primary
) = type_binfo
;
1890 /* A virtual binfo might have been copied from within
1891 another hierarchy. As we're about to use it as a primary
1892 base, make sure the offsets match. */
1893 delta
= size_diffop_loc (input_location
, ssize_int (0),
1894 fold_convert (ssizetype
, BINFO_OFFSET (primary
)));
1896 propagate_binfo_offsets (primary
, delta
);
1899 primary
= TYPE_BINFO (basetype
);
1901 TYPE_VFIELD (t
) = TYPE_VFIELD (basetype
);
1902 BINFO_VTABLE (type_binfo
) = BINFO_VTABLE (primary
);
1903 BINFO_VIRTUALS (type_binfo
) = BINFO_VIRTUALS (primary
);
1907 /* Update the variant types of T. */
1910 fixup_type_variants (tree t
)
1917 for (variants
= TYPE_NEXT_VARIANT (t
);
1919 variants
= TYPE_NEXT_VARIANT (variants
))
1921 /* These fields are in the _TYPE part of the node, not in
1922 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1923 TYPE_HAS_USER_CONSTRUCTOR (variants
) = TYPE_HAS_USER_CONSTRUCTOR (t
);
1924 TYPE_NEEDS_CONSTRUCTING (variants
) = TYPE_NEEDS_CONSTRUCTING (t
);
1925 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants
)
1926 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t
);
1928 TYPE_POLYMORPHIC_P (variants
) = TYPE_POLYMORPHIC_P (t
);
1930 TYPE_BINFO (variants
) = TYPE_BINFO (t
);
1932 /* Copy whatever these are holding today. */
1933 TYPE_VFIELD (variants
) = TYPE_VFIELD (t
);
1934 TYPE_FIELDS (variants
) = TYPE_FIELDS (t
);
1938 /* KLASS is a class that we're applying may_alias to after the body is
1939 parsed. Fixup any POINTER_TO and REFERENCE_TO types. The
1940 canonical type(s) will be implicitly updated. */
1943 fixup_may_alias (tree klass
)
1947 for (t
= TYPE_POINTER_TO (klass
); t
; t
= TYPE_NEXT_PTR_TO (t
))
1948 for (v
= TYPE_MAIN_VARIANT (t
); v
; v
= TYPE_NEXT_VARIANT (v
))
1949 TYPE_REF_CAN_ALIAS_ALL (v
) = true;
1950 for (t
= TYPE_REFERENCE_TO (klass
); t
; t
= TYPE_NEXT_REF_TO (t
))
1951 for (v
= TYPE_MAIN_VARIANT (t
); v
; v
= TYPE_NEXT_VARIANT (v
))
1952 TYPE_REF_CAN_ALIAS_ALL (v
) = true;
1955 /* Early variant fixups: we apply attributes at the beginning of the class
1956 definition, and we need to fix up any variants that have already been
1957 made via elaborated-type-specifier so that check_qualified_type works. */
1960 fixup_attribute_variants (tree t
)
1967 tree attrs
= TYPE_ATTRIBUTES (t
);
1968 unsigned align
= TYPE_ALIGN (t
);
1969 bool user_align
= TYPE_USER_ALIGN (t
);
1970 bool may_alias
= lookup_attribute ("may_alias", attrs
);
1973 fixup_may_alias (t
);
1975 for (variants
= TYPE_NEXT_VARIANT (t
);
1977 variants
= TYPE_NEXT_VARIANT (variants
))
1979 /* These are the two fields that check_qualified_type looks at and
1980 are affected by attributes. */
1981 TYPE_ATTRIBUTES (variants
) = attrs
;
1982 unsigned valign
= align
;
1983 if (TYPE_USER_ALIGN (variants
))
1984 valign
= MAX (valign
, TYPE_ALIGN (variants
));
1986 TYPE_USER_ALIGN (variants
) = user_align
;
1987 SET_TYPE_ALIGN (variants
, valign
);
1989 fixup_may_alias (variants
);
1993 /* Set memoizing fields and bits of T (and its variants) for later
1997 finish_struct_bits (tree t
)
1999 /* Fix up variants (if any). */
2000 fixup_type_variants (t
);
2002 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t
)) && TYPE_POLYMORPHIC_P (t
))
2003 /* For a class w/o baseclasses, 'finish_struct' has set
2004 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
2005 Similarly for a class whose base classes do not have vtables.
2006 When neither of these is true, we might have removed abstract
2007 virtuals (by providing a definition), added some (by declaring
2008 new ones), or redeclared ones from a base class. We need to
2009 recalculate what's really an abstract virtual at this point (by
2010 looking in the vtables). */
2011 get_pure_virtuals (t
);
2013 /* If this type has a copy constructor or a destructor, force its
2014 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
2015 nonzero. This will cause it to be passed by invisible reference
2016 and prevent it from being returned in a register. */
2017 if (type_has_nontrivial_copy_init (t
)
2018 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t
))
2021 SET_DECL_MODE (TYPE_MAIN_DECL (t
), BLKmode
);
2022 for (variants
= t
; variants
; variants
= TYPE_NEXT_VARIANT (variants
))
2024 SET_TYPE_MODE (variants
, BLKmode
);
2025 TREE_ADDRESSABLE (variants
) = 1;
2030 /* Issue warnings about T having private constructors, but no friends,
2033 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
2034 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
2035 non-private static member functions. */
2038 maybe_warn_about_overly_private_class (tree t
)
2040 int has_member_fn
= 0;
2041 int has_nonprivate_method
= 0;
2043 if (!warn_ctor_dtor_privacy
2044 /* If the class has friends, those entities might create and
2045 access instances, so we should not warn. */
2046 || (CLASSTYPE_FRIEND_CLASSES (t
)
2047 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t
)))
2048 /* We will have warned when the template was declared; there's
2049 no need to warn on every instantiation. */
2050 || CLASSTYPE_TEMPLATE_INSTANTIATION (t
))
2051 /* There's no reason to even consider warning about this
2055 /* We only issue one warning, if more than one applies, because
2056 otherwise, on code like:
2059 // Oops - forgot `public:'
2065 we warn several times about essentially the same problem. */
2067 /* Check to see if all (non-constructor, non-destructor) member
2068 functions are private. (Since there are no friends or
2069 non-private statics, we can't ever call any of the private member
2071 for (tree fn
= TYPE_FIELDS (t
); fn
; fn
= DECL_CHAIN (fn
))
2072 if (!DECL_DECLARES_FUNCTION_P (fn
))
2073 /* Not a function. */;
2074 else if (DECL_ARTIFICIAL (fn
))
2075 /* We're not interested in compiler-generated methods; they don't
2076 provide any way to call private members. */;
2077 else if (!TREE_PRIVATE (fn
))
2079 if (DECL_STATIC_FUNCTION_P (fn
))
2080 /* A non-private static member function is just like a
2081 friend; it can create and invoke private member
2082 functions, and be accessed without a class
2086 has_nonprivate_method
= 1;
2087 /* Keep searching for a static member function. */
2089 else if (!DECL_CONSTRUCTOR_P (fn
) && !DECL_DESTRUCTOR_P (fn
))
2092 if (!has_nonprivate_method
&& has_member_fn
)
2094 /* There are no non-private methods, and there's at least one
2095 private member function that isn't a constructor or
2096 destructor. (If all the private members are
2097 constructors/destructors we want to use the code below that
2098 issues error messages specifically referring to
2099 constructors/destructors.) */
2101 tree binfo
= TYPE_BINFO (t
);
2103 for (i
= 0; i
!= BINFO_N_BASE_BINFOS (binfo
); i
++)
2104 if (BINFO_BASE_ACCESS (binfo
, i
) != access_private_node
)
2106 has_nonprivate_method
= 1;
2109 if (!has_nonprivate_method
)
2111 warning (OPT_Wctor_dtor_privacy
,
2112 "all member functions in class %qT are private", t
);
2117 /* Even if some of the member functions are non-private, the class
2118 won't be useful for much if all the constructors or destructors
2119 are private: such an object can never be created or destroyed. */
2120 if (tree dtor
= CLASSTYPE_DESTRUCTOR (t
))
2121 if (TREE_PRIVATE (dtor
))
2123 warning (OPT_Wctor_dtor_privacy
,
2124 "%q#T only defines a private destructor and has no friends",
2129 /* Warn about classes that have private constructors and no friends. */
2130 if (TYPE_HAS_USER_CONSTRUCTOR (t
)
2131 /* Implicitly generated constructors are always public. */
2132 && !CLASSTYPE_LAZY_DEFAULT_CTOR (t
))
2134 bool nonprivate_ctor
= false;
2135 tree copy_or_move
= NULL_TREE
;
2137 /* If a non-template class does not define a copy
2138 constructor, one is defined for it, enabling it to avoid
2139 this warning. For a template class, this does not
2140 happen, and so we would normally get a warning on:
2142 template <class T> class C { private: C(); };
2144 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
2145 complete non-template or fully instantiated classes have this
2147 if (!TYPE_HAS_COPY_CTOR (t
))
2148 nonprivate_ctor
= true;
2150 for (ovl_iterator
iter (CLASSTYPE_CONSTRUCTORS (t
));
2151 !nonprivate_ctor
&& iter
; ++iter
)
2152 if (TREE_PRIVATE (*iter
))
2154 else if (copy_fn_p (*iter
) || move_fn_p (*iter
))
2155 /* Ideally, we wouldn't count any constructor that takes
2156 an argument of the class type as a parameter, because
2157 such things cannot be used to construct an instance of
2158 the class unless you already have one. */
2159 copy_or_move
= *iter
;
2161 nonprivate_ctor
= true;
2163 if (!nonprivate_ctor
)
2165 warning (OPT_Wctor_dtor_privacy
,
2166 "%q#T only defines private constructors and has no friends",
2169 inform (DECL_SOURCE_LOCATION (copy_or_move
),
2170 "%q#D is public, but requires an existing %q#T object",
2177 /* Make BINFO's vtable have N entries, including RTTI entries,
2178 vbase and vcall offsets, etc. Set its type and call the back end
2182 layout_vtable_decl (tree binfo
, int n
)
2187 atype
= build_array_of_n_type (vtable_entry_type
, n
);
2188 layout_type (atype
);
2190 /* We may have to grow the vtable. */
2191 vtable
= get_vtbl_decl_for_binfo (binfo
);
2192 if (!same_type_p (TREE_TYPE (vtable
), atype
))
2194 TREE_TYPE (vtable
) = atype
;
2195 DECL_SIZE (vtable
) = DECL_SIZE_UNIT (vtable
) = NULL_TREE
;
2196 layout_decl (vtable
, 0);
2200 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
2201 have the same signature. */
2204 same_signature_p (const_tree fndecl
, const_tree base_fndecl
)
2206 /* One destructor overrides another if they are the same kind of
2208 if (DECL_DESTRUCTOR_P (base_fndecl
) && DECL_DESTRUCTOR_P (fndecl
)
2209 && special_function_p (base_fndecl
) == special_function_p (fndecl
))
2211 /* But a non-destructor never overrides a destructor, nor vice
2212 versa, nor do different kinds of destructors override
2213 one-another. For example, a complete object destructor does not
2214 override a deleting destructor. */
2215 if (DECL_DESTRUCTOR_P (base_fndecl
) || DECL_DESTRUCTOR_P (fndecl
))
2218 if (DECL_NAME (fndecl
) == DECL_NAME (base_fndecl
)
2219 || (DECL_CONV_FN_P (fndecl
)
2220 && DECL_CONV_FN_P (base_fndecl
)
2221 && same_type_p (DECL_CONV_FN_TYPE (fndecl
),
2222 DECL_CONV_FN_TYPE (base_fndecl
))))
2224 tree fntype
= TREE_TYPE (fndecl
);
2225 tree base_fntype
= TREE_TYPE (base_fndecl
);
2226 if (type_memfn_quals (fntype
) == type_memfn_quals (base_fntype
)
2227 && type_memfn_rqual (fntype
) == type_memfn_rqual (base_fntype
)
2228 && compparms (FUNCTION_FIRST_USER_PARMTYPE (fndecl
),
2229 FUNCTION_FIRST_USER_PARMTYPE (base_fndecl
)))
2235 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
2239 base_derived_from (tree derived
, tree base
)
2243 for (probe
= base
; probe
; probe
= BINFO_INHERITANCE_CHAIN (probe
))
2245 if (probe
== derived
)
2247 else if (BINFO_VIRTUAL_P (probe
))
2248 /* If we meet a virtual base, we can't follow the inheritance
2249 any more. See if the complete type of DERIVED contains
2250 such a virtual base. */
2251 return (binfo_for_vbase (BINFO_TYPE (probe
), BINFO_TYPE (derived
))
2257 struct find_final_overrider_data
{
2258 /* The function for which we are trying to find a final overrider. */
2260 /* The base class in which the function was declared. */
2261 tree declaring_base
;
2262 /* The candidate overriders. */
2264 /* Path to most derived. */
2268 /* Add the overrider along the current path to FFOD->CANDIDATES.
2269 Returns true if an overrider was found; false otherwise. */
2272 dfs_find_final_overrider_1 (tree binfo
,
2273 find_final_overrider_data
*ffod
,
2278 /* If BINFO is not the most derived type, try a more derived class.
2279 A definition there will overrider a definition here. */
2283 if (dfs_find_final_overrider_1
2284 (ffod
->path
[depth
], ffod
, depth
))
2288 method
= look_for_overrides_here (BINFO_TYPE (binfo
), ffod
->fn
);
2291 tree
*candidate
= &ffod
->candidates
;
2293 /* Remove any candidates overridden by this new function. */
2296 /* If *CANDIDATE overrides METHOD, then METHOD
2297 cannot override anything else on the list. */
2298 if (base_derived_from (TREE_VALUE (*candidate
), binfo
))
2300 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
2301 if (base_derived_from (binfo
, TREE_VALUE (*candidate
)))
2302 *candidate
= TREE_CHAIN (*candidate
);
2304 candidate
= &TREE_CHAIN (*candidate
);
2307 /* Add the new function. */
2308 ffod
->candidates
= tree_cons (method
, binfo
, ffod
->candidates
);
2315 /* Called from find_final_overrider via dfs_walk. */
2318 dfs_find_final_overrider_pre (tree binfo
, void *data
)
2320 find_final_overrider_data
*ffod
= (find_final_overrider_data
*) data
;
2322 if (binfo
== ffod
->declaring_base
)
2323 dfs_find_final_overrider_1 (binfo
, ffod
, ffod
->path
.length ());
2324 ffod
->path
.safe_push (binfo
);
2330 dfs_find_final_overrider_post (tree
/*binfo*/, void *data
)
2332 find_final_overrider_data
*ffod
= (find_final_overrider_data
*) data
;
2338 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
2339 FN and whose TREE_VALUE is the binfo for the base where the
2340 overriding occurs. BINFO (in the hierarchy dominated by the binfo
2341 DERIVED) is the base object in which FN is declared. */
2344 find_final_overrider (tree derived
, tree binfo
, tree fn
)
2346 find_final_overrider_data ffod
;
2348 /* Getting this right is a little tricky. This is valid:
2350 struct S { virtual void f (); };
2351 struct T { virtual void f (); };
2352 struct U : public S, public T { };
2354 even though calling `f' in `U' is ambiguous. But,
2356 struct R { virtual void f(); };
2357 struct S : virtual public R { virtual void f (); };
2358 struct T : virtual public R { virtual void f (); };
2359 struct U : public S, public T { };
2361 is not -- there's no way to decide whether to put `S::f' or
2362 `T::f' in the vtable for `R'.
2364 The solution is to look at all paths to BINFO. If we find
2365 different overriders along any two, then there is a problem. */
2366 if (DECL_THUNK_P (fn
))
2367 fn
= THUNK_TARGET (fn
);
2369 /* Determine the depth of the hierarchy. */
2371 ffod
.declaring_base
= binfo
;
2372 ffod
.candidates
= NULL_TREE
;
2373 ffod
.path
.create (30);
2375 dfs_walk_all (derived
, dfs_find_final_overrider_pre
,
2376 dfs_find_final_overrider_post
, &ffod
);
2378 ffod
.path
.release ();
2380 /* If there was no winner, issue an error message. */
2381 if (!ffod
.candidates
|| TREE_CHAIN (ffod
.candidates
))
2382 return error_mark_node
;
2384 return ffod
.candidates
;
2387 /* Return the index of the vcall offset for FN when TYPE is used as a
2391 get_vcall_index (tree fn
, tree type
)
2393 vec
<tree_pair_s
, va_gc
> *indices
= CLASSTYPE_VCALL_INDICES (type
);
2397 FOR_EACH_VEC_SAFE_ELT (indices
, ix
, p
)
2398 if ((DECL_DESTRUCTOR_P (fn
) && DECL_DESTRUCTOR_P (p
->purpose
))
2399 || same_signature_p (fn
, p
->purpose
))
2402 /* There should always be an appropriate index. */
2406 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2407 dominated by T. FN is the old function; VIRTUALS points to the
2408 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2409 of that entry in the list. */
2412 update_vtable_entry_for_fn (tree t
, tree binfo
, tree fn
, tree
* virtuals
,
2420 tree overrider_fn
, overrider_target
;
2421 tree target_fn
= DECL_THUNK_P (fn
) ? THUNK_TARGET (fn
) : fn
;
2422 tree over_return
, base_return
;
2425 /* Find the nearest primary base (possibly binfo itself) which defines
2426 this function; this is the class the caller will convert to when
2427 calling FN through BINFO. */
2428 for (b
= binfo
; ; b
= get_primary_binfo (b
))
2431 if (look_for_overrides_here (BINFO_TYPE (b
), target_fn
))
2434 /* The nearest definition is from a lost primary. */
2435 if (BINFO_LOST_PRIMARY_P (b
))
2440 /* Find the final overrider. */
2441 overrider
= find_final_overrider (TYPE_BINFO (t
), b
, target_fn
);
2442 if (overrider
== error_mark_node
)
2444 error ("no unique final overrider for %qD in %qT", target_fn
, t
);
2447 overrider_target
= overrider_fn
= TREE_PURPOSE (overrider
);
2449 /* Check for adjusting covariant return types. */
2450 over_return
= TREE_TYPE (TREE_TYPE (overrider_target
));
2451 base_return
= TREE_TYPE (TREE_TYPE (target_fn
));
2453 if (POINTER_TYPE_P (over_return
)
2454 && TREE_CODE (over_return
) == TREE_CODE (base_return
)
2455 && CLASS_TYPE_P (TREE_TYPE (over_return
))
2456 && CLASS_TYPE_P (TREE_TYPE (base_return
))
2457 /* If the overrider is invalid, don't even try. */
2458 && !DECL_INVALID_OVERRIDER_P (overrider_target
))
2460 /* If FN is a covariant thunk, we must figure out the adjustment
2461 to the final base FN was converting to. As OVERRIDER_TARGET might
2462 also be converting to the return type of FN, we have to
2463 combine the two conversions here. */
2464 tree fixed_offset
, virtual_offset
;
2466 over_return
= TREE_TYPE (over_return
);
2467 base_return
= TREE_TYPE (base_return
);
2469 if (DECL_THUNK_P (fn
))
2471 gcc_assert (DECL_RESULT_THUNK_P (fn
));
2472 fixed_offset
= ssize_int (THUNK_FIXED_OFFSET (fn
));
2473 virtual_offset
= THUNK_VIRTUAL_OFFSET (fn
);
2476 fixed_offset
= virtual_offset
= NULL_TREE
;
2479 /* Find the equivalent binfo within the return type of the
2480 overriding function. We will want the vbase offset from
2482 virtual_offset
= binfo_for_vbase (BINFO_TYPE (virtual_offset
),
2484 else if (!same_type_ignoring_top_level_qualifiers_p
2485 (over_return
, base_return
))
2487 /* There was no existing virtual thunk (which takes
2488 precedence). So find the binfo of the base function's
2489 return type within the overriding function's return type.
2490 Fortunately we know the covariancy is valid (it
2491 has already been checked), so we can just iterate along
2492 the binfos, which have been chained in inheritance graph
2493 order. Of course it is lame that we have to repeat the
2494 search here anyway -- we should really be caching pieces
2495 of the vtable and avoiding this repeated work. */
2496 tree thunk_binfo
, base_binfo
;
2498 /* Find the base binfo within the overriding function's
2499 return type. We will always find a thunk_binfo, except
2500 when the covariancy is invalid (which we will have
2501 already diagnosed). */
2502 for (base_binfo
= TYPE_BINFO (base_return
),
2503 thunk_binfo
= TYPE_BINFO (over_return
);
2505 thunk_binfo
= TREE_CHAIN (thunk_binfo
))
2506 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo
),
2507 BINFO_TYPE (base_binfo
)))
2510 /* See if virtual inheritance is involved. */
2511 for (virtual_offset
= thunk_binfo
;
2513 virtual_offset
= BINFO_INHERITANCE_CHAIN (virtual_offset
))
2514 if (BINFO_VIRTUAL_P (virtual_offset
))
2518 || (thunk_binfo
&& !BINFO_OFFSET_ZEROP (thunk_binfo
)))
2520 tree offset
= fold_convert (ssizetype
, BINFO_OFFSET (thunk_binfo
));
2524 /* We convert via virtual base. Adjust the fixed
2525 offset to be from there. */
2527 size_diffop (offset
,
2528 fold_convert (ssizetype
,
2529 BINFO_OFFSET (virtual_offset
)));
2532 /* There was an existing fixed offset, this must be
2533 from the base just converted to, and the base the
2534 FN was thunking to. */
2535 fixed_offset
= size_binop (PLUS_EXPR
, fixed_offset
, offset
);
2537 fixed_offset
= offset
;
2541 if (fixed_offset
|| virtual_offset
)
2542 /* Replace the overriding function with a covariant thunk. We
2543 will emit the overriding function in its own slot as
2545 overrider_fn
= make_thunk (overrider_target
, /*this_adjusting=*/0,
2546 fixed_offset
, virtual_offset
);
2549 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target
) ||
2550 !DECL_THUNK_P (fn
));
2552 /* If we need a covariant thunk, then we may need to adjust first_defn.
2553 The ABI specifies that the thunks emitted with a function are
2554 determined by which bases the function overrides, so we need to be
2555 sure that we're using a thunk for some overridden base; even if we
2556 know that the necessary this adjustment is zero, there may not be an
2557 appropriate zero-this-adjustment thunk for us to use since thunks for
2558 overriding virtual bases always use the vcall offset.
2560 Furthermore, just choosing any base that overrides this function isn't
2561 quite right, as this slot won't be used for calls through a type that
2562 puts a covariant thunk here. Calling the function through such a type
2563 will use a different slot, and that slot is the one that determines
2564 the thunk emitted for that base.
2566 So, keep looking until we find the base that we're really overriding
2567 in this slot: the nearest primary base that doesn't use a covariant
2568 thunk in this slot. */
2569 if (overrider_target
!= overrider_fn
)
2571 if (BINFO_TYPE (b
) == DECL_CONTEXT (overrider_target
))
2572 /* We already know that the overrider needs a covariant thunk. */
2573 b
= get_primary_binfo (b
);
2574 for (; ; b
= get_primary_binfo (b
))
2576 tree main_binfo
= TYPE_BINFO (BINFO_TYPE (b
));
2577 tree bv
= chain_index (ix
, BINFO_VIRTUALS (main_binfo
));
2578 if (!DECL_THUNK_P (TREE_VALUE (bv
)))
2580 if (BINFO_LOST_PRIMARY_P (b
))
2586 /* Assume that we will produce a thunk that convert all the way to
2587 the final overrider, and not to an intermediate virtual base. */
2588 virtual_base
= NULL_TREE
;
2590 /* See if we can convert to an intermediate virtual base first, and then
2591 use the vcall offset located there to finish the conversion. */
2592 for (; b
; b
= BINFO_INHERITANCE_CHAIN (b
))
2594 /* If we find the final overrider, then we can stop
2596 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b
),
2597 BINFO_TYPE (TREE_VALUE (overrider
))))
2600 /* If we find a virtual base, and we haven't yet found the
2601 overrider, then there is a virtual base between the
2602 declaring base (first_defn) and the final overrider. */
2603 if (BINFO_VIRTUAL_P (b
))
2610 /* Compute the constant adjustment to the `this' pointer. The
2611 `this' pointer, when this function is called, will point at BINFO
2612 (or one of its primary bases, which are at the same offset). */
2614 /* The `this' pointer needs to be adjusted from the declaration to
2615 the nearest virtual base. */
2616 delta
= size_diffop_loc (input_location
,
2617 fold_convert (ssizetype
, BINFO_OFFSET (virtual_base
)),
2618 fold_convert (ssizetype
, BINFO_OFFSET (first_defn
)));
2620 /* If the nearest definition is in a lost primary, we don't need an
2621 entry in our vtable. Except possibly in a constructor vtable,
2622 if we happen to get our primary back. In that case, the offset
2623 will be zero, as it will be a primary base. */
2624 delta
= size_zero_node
;
2626 /* The `this' pointer needs to be adjusted from pointing to
2627 BINFO to pointing at the base where the final overrider
2629 delta
= size_diffop_loc (input_location
,
2630 fold_convert (ssizetype
,
2631 BINFO_OFFSET (TREE_VALUE (overrider
))),
2632 fold_convert (ssizetype
, BINFO_OFFSET (binfo
)));
2634 modify_vtable_entry (t
, binfo
, overrider_fn
, delta
, virtuals
);
2637 BV_VCALL_INDEX (*virtuals
)
2638 = get_vcall_index (overrider_target
, BINFO_TYPE (virtual_base
));
2640 BV_VCALL_INDEX (*virtuals
) = NULL_TREE
;
2642 BV_LOST_PRIMARY (*virtuals
) = lost
;
2645 /* Called from modify_all_vtables via dfs_walk. */
2648 dfs_modify_vtables (tree binfo
, void* data
)
2650 tree t
= (tree
) data
;
2655 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo
)))
2656 /* A base without a vtable needs no modification, and its bases
2657 are uninteresting. */
2658 return dfs_skip_bases
;
2660 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), t
)
2661 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t
))
2662 /* Don't do the primary vtable, if it's new. */
2665 if (BINFO_PRIMARY_P (binfo
) && !BINFO_VIRTUAL_P (binfo
))
2666 /* There's no need to modify the vtable for a non-virtual primary
2667 base; we're not going to use that vtable anyhow. We do still
2668 need to do this for virtual primary bases, as they could become
2669 non-primary in a construction vtable. */
2672 make_new_vtable (t
, binfo
);
2674 /* Now, go through each of the virtual functions in the virtual
2675 function table for BINFO. Find the final overrider, and update
2676 the BINFO_VIRTUALS list appropriately. */
2677 for (ix
= 0, virtuals
= BINFO_VIRTUALS (binfo
),
2678 old_virtuals
= BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo
)));
2680 ix
++, virtuals
= TREE_CHAIN (virtuals
),
2681 old_virtuals
= TREE_CHAIN (old_virtuals
))
2682 update_vtable_entry_for_fn (t
,
2684 BV_FN (old_virtuals
),
2690 /* Update all of the primary and secondary vtables for T. Create new
2691 vtables as required, and initialize their RTTI information. Each
2692 of the functions in VIRTUALS is declared in T and may override a
2693 virtual function from a base class; find and modify the appropriate
2694 entries to point to the overriding functions. Returns a list, in
2695 declaration order, of the virtual functions that are declared in T,
2696 but do not appear in the primary base class vtable, and which
2697 should therefore be appended to the end of the vtable for T. */
2700 modify_all_vtables (tree t
, tree virtuals
)
2702 tree binfo
= TYPE_BINFO (t
);
2705 /* Mangle the vtable name before entering dfs_walk (c++/51884). */
2706 if (TYPE_CONTAINS_VPTR_P (t
))
2707 get_vtable_decl (t
, false);
2709 /* Update all of the vtables. */
2710 dfs_walk_once (binfo
, dfs_modify_vtables
, NULL
, t
);
2712 /* Add virtual functions not already in our primary vtable. These
2713 will be both those introduced by this class, and those overridden
2714 from secondary bases. It does not include virtuals merely
2715 inherited from secondary bases. */
2716 for (fnsp
= &virtuals
; *fnsp
; )
2718 tree fn
= TREE_VALUE (*fnsp
);
2720 if (!value_member (fn
, BINFO_VIRTUALS (binfo
))
2721 || DECL_VINDEX (fn
) == error_mark_node
)
2723 /* We don't need to adjust the `this' pointer when
2724 calling this function. */
2725 BV_DELTA (*fnsp
) = integer_zero_node
;
2726 BV_VCALL_INDEX (*fnsp
) = NULL_TREE
;
2728 /* This is a function not already in our vtable. Keep it. */
2729 fnsp
= &TREE_CHAIN (*fnsp
);
2732 /* We've already got an entry for this function. Skip it. */
2733 *fnsp
= TREE_CHAIN (*fnsp
);
2739 /* Get the base virtual function declarations in T that have the
2743 get_basefndecls (tree name
, tree t
, vec
<tree
> *base_fndecls
)
2745 bool found_decls
= false;
2747 /* Find virtual functions in T with the indicated NAME. */
2748 for (ovl_iterator
iter (get_class_binding (t
, name
)); iter
; ++iter
)
2750 tree method
= *iter
;
2752 if (TREE_CODE (method
) == FUNCTION_DECL
&& DECL_VINDEX (method
))
2754 base_fndecls
->safe_push (method
);
2762 int n_baseclasses
= BINFO_N_BASE_BINFOS (TYPE_BINFO (t
));
2763 for (int i
= 0; i
< n_baseclasses
; i
++)
2765 tree basetype
= BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t
), i
));
2766 get_basefndecls (name
, basetype
, base_fndecls
);
2770 /* If this declaration supersedes the declaration of
2771 a method declared virtual in the base class, then
2772 mark this field as being virtual as well. */
2775 check_for_override (tree decl
, tree ctype
)
2777 bool overrides_found
= false;
2778 if (TREE_CODE (decl
) == TEMPLATE_DECL
)
2779 /* In [temp.mem] we have:
2781 A specialization of a member function template does not
2782 override a virtual function from a base class. */
2784 if ((DECL_DESTRUCTOR_P (decl
)
2785 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl
))
2786 || DECL_CONV_FN_P (decl
))
2787 && look_for_overrides (ctype
, decl
)
2788 && !DECL_STATIC_FUNCTION_P (decl
))
2789 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2790 the error_mark_node so that we know it is an overriding
2793 DECL_VINDEX (decl
) = decl
;
2794 overrides_found
= true;
2795 if (warn_override
&& !DECL_OVERRIDE_P (decl
)
2796 && !DECL_DESTRUCTOR_P (decl
))
2797 warning_at (DECL_SOURCE_LOCATION (decl
), OPT_Wsuggest_override
,
2798 "%qD can be marked override", decl
);
2801 if (DECL_VIRTUAL_P (decl
))
2803 if (!DECL_VINDEX (decl
))
2804 DECL_VINDEX (decl
) = error_mark_node
;
2805 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl
)) = 1;
2806 if (DECL_DESTRUCTOR_P (decl
))
2807 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (ctype
) = true;
2809 else if (DECL_FINAL_P (decl
))
2810 error ("%q+#D marked %<final%>, but is not virtual", decl
);
2811 if (DECL_OVERRIDE_P (decl
) && !overrides_found
)
2812 error ("%q+#D marked %<override%>, but does not override", decl
);
2815 /* Warn about hidden virtual functions that are not overridden in t.
2816 We know that constructors and destructors don't apply. */
2819 warn_hidden (tree t
)
2821 if (vec
<tree
, va_gc
> *member_vec
= CLASSTYPE_MEMBER_VEC (t
))
2822 for (unsigned ix
= member_vec
->length (); ix
--;)
2824 tree fns
= (*member_vec
)[ix
];
2829 tree name
= OVL_NAME (fns
);
2830 auto_vec
<tree
, 20> base_fndecls
;
2835 /* Iterate through all of the base classes looking for possibly
2836 hidden functions. */
2837 for (binfo
= TYPE_BINFO (t
), j
= 0;
2838 BINFO_BASE_ITERATE (binfo
, j
, base_binfo
); j
++)
2840 tree basetype
= BINFO_TYPE (base_binfo
);
2841 get_basefndecls (name
, basetype
, &base_fndecls
);
2844 /* If there are no functions to hide, continue. */
2845 if (base_fndecls
.is_empty ())
2848 /* Remove any overridden functions. */
2849 for (ovl_iterator
iter (fns
); iter
; ++iter
)
2851 tree fndecl
= *iter
;
2852 if (TREE_CODE (fndecl
) == FUNCTION_DECL
2853 && DECL_VINDEX (fndecl
))
2855 /* If the method from the base class has the same
2856 signature as the method from the derived class, it
2857 has been overridden. */
2858 for (size_t k
= 0; k
< base_fndecls
.length (); k
++)
2860 && same_signature_p (fndecl
, base_fndecls
[k
]))
2861 base_fndecls
[k
] = NULL_TREE
;
2865 /* Now give a warning for all base functions without overriders,
2866 as they are hidden. */
2868 FOR_EACH_VEC_ELT (base_fndecls
, j
, base_fndecl
)
2871 /* Here we know it is a hider, and no overrider exists. */
2872 warning_at (location_of (base_fndecl
),
2873 OPT_Woverloaded_virtual
,
2874 "%qD was hidden", base_fndecl
);
2875 warning_at (location_of (fns
),
2876 OPT_Woverloaded_virtual
, " by %qD", fns
);
2881 /* Recursive helper for finish_struct_anon. */
2884 finish_struct_anon_r (tree field
, bool complain
)
2886 bool is_union
= TREE_CODE (TREE_TYPE (field
)) == UNION_TYPE
;
2887 tree elt
= TYPE_FIELDS (TREE_TYPE (field
));
2888 for (; elt
; elt
= DECL_CHAIN (elt
))
2890 /* We're generally only interested in entities the user
2891 declared, but we also find nested classes by noticing
2892 the TYPE_DECL that we create implicitly. You're
2893 allowed to put one anonymous union inside another,
2894 though, so we explicitly tolerate that. We use
2895 TYPE_UNNAMED_P rather than ANON_AGGR_TYPE_P so that
2896 we also allow unnamed types used for defining fields. */
2897 if (DECL_ARTIFICIAL (elt
)
2898 && (!DECL_IMPLICIT_TYPEDEF_P (elt
)
2899 || TYPE_UNNAMED_P (TREE_TYPE (elt
))))
2902 if (TREE_CODE (elt
) != FIELD_DECL
)
2904 /* We already complained about static data members in
2905 finish_static_data_member_decl. */
2906 if (complain
&& !VAR_P (elt
))
2909 permerror (DECL_SOURCE_LOCATION (elt
),
2910 "%q#D invalid; an anonymous union can "
2911 "only have non-static data members", elt
);
2913 permerror (DECL_SOURCE_LOCATION (elt
),
2914 "%q#D invalid; an anonymous struct can "
2915 "only have non-static data members", elt
);
2922 if (TREE_PRIVATE (elt
))
2925 permerror (DECL_SOURCE_LOCATION (elt
),
2926 "private member %q#D in anonymous union", elt
);
2928 permerror (DECL_SOURCE_LOCATION (elt
),
2929 "private member %q#D in anonymous struct", elt
);
2931 else if (TREE_PROTECTED (elt
))
2934 permerror (DECL_SOURCE_LOCATION (elt
),
2935 "protected member %q#D in anonymous union", elt
);
2937 permerror (DECL_SOURCE_LOCATION (elt
),
2938 "protected member %q#D in anonymous struct", elt
);
2942 TREE_PRIVATE (elt
) = TREE_PRIVATE (field
);
2943 TREE_PROTECTED (elt
) = TREE_PROTECTED (field
);
2945 /* Recurse into the anonymous aggregates to handle correctly
2946 access control (c++/24926):
2957 if (DECL_NAME (elt
) == NULL_TREE
2958 && ANON_AGGR_TYPE_P (TREE_TYPE (elt
)))
2959 finish_struct_anon_r (elt
, /*complain=*/false);
2963 /* Check for things that are invalid. There are probably plenty of other
2964 things we should check for also. */
2967 finish_struct_anon (tree t
)
2969 for (tree field
= TYPE_FIELDS (t
); field
; field
= DECL_CHAIN (field
))
2971 if (TREE_STATIC (field
))
2973 if (TREE_CODE (field
) != FIELD_DECL
)
2976 if (DECL_NAME (field
) == NULL_TREE
2977 && ANON_AGGR_TYPE_P (TREE_TYPE (field
)))
2978 finish_struct_anon_r (field
, /*complain=*/true);
2982 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2983 will be used later during class template instantiation.
2984 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2985 a non-static member data (FIELD_DECL), a member function
2986 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2987 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2988 When FRIEND_P is nonzero, T is either a friend class
2989 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2990 (FUNCTION_DECL, TEMPLATE_DECL). */
2993 maybe_add_class_template_decl_list (tree type
, tree t
, int friend_p
)
2995 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2996 if (CLASSTYPE_TEMPLATE_INFO (type
))
2997 CLASSTYPE_DECL_LIST (type
)
2998 = tree_cons (friend_p
? NULL_TREE
: type
,
2999 t
, CLASSTYPE_DECL_LIST (type
));
3002 /* This function is called from declare_virt_assop_and_dtor via
3005 DATA is a type that direcly or indirectly inherits the base
3006 represented by BINFO. If BINFO contains a virtual assignment [copy
3007 assignment or move assigment] operator or a virtual constructor,
3008 declare that function in DATA if it hasn't been already declared. */
3011 dfs_declare_virt_assop_and_dtor (tree binfo
, void *data
)
3013 tree bv
, fn
, t
= (tree
)data
;
3014 tree opname
= cp_assignment_operator_id (NOP_EXPR
);
3016 gcc_assert (t
&& CLASS_TYPE_P (t
));
3017 gcc_assert (binfo
&& TREE_CODE (binfo
) == TREE_BINFO
);
3019 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo
)))
3020 /* A base without a vtable needs no modification, and its bases
3021 are uninteresting. */
3022 return dfs_skip_bases
;
3024 if (BINFO_PRIMARY_P (binfo
))
3025 /* If this is a primary base, then we have already looked at the
3026 virtual functions of its vtable. */
3029 for (bv
= BINFO_VIRTUALS (binfo
); bv
; bv
= TREE_CHAIN (bv
))
3033 if (DECL_NAME (fn
) == opname
)
3035 if (CLASSTYPE_LAZY_COPY_ASSIGN (t
))
3036 lazily_declare_fn (sfk_copy_assignment
, t
);
3037 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t
))
3038 lazily_declare_fn (sfk_move_assignment
, t
);
3040 else if (DECL_DESTRUCTOR_P (fn
)
3041 && CLASSTYPE_LAZY_DESTRUCTOR (t
))
3042 lazily_declare_fn (sfk_destructor
, t
);
3048 /* If the class type T has a direct or indirect base that contains a
3049 virtual assignment operator or a virtual destructor, declare that
3050 function in T if it hasn't been already declared. */
3053 declare_virt_assop_and_dtor (tree t
)
3055 if (!(TYPE_POLYMORPHIC_P (t
)
3056 && (CLASSTYPE_LAZY_COPY_ASSIGN (t
)
3057 || CLASSTYPE_LAZY_MOVE_ASSIGN (t
)
3058 || CLASSTYPE_LAZY_DESTRUCTOR (t
))))
3061 dfs_walk_all (TYPE_BINFO (t
),
3062 dfs_declare_virt_assop_and_dtor
,
3066 /* Declare the inheriting constructor for class T inherited from base
3067 constructor CTOR with the parameter array PARMS of size NPARMS. */
3070 one_inheriting_sig (tree t
, tree ctor
, tree
*parms
, int nparms
)
3072 gcc_assert (TYPE_MAIN_VARIANT (t
) == t
);
3074 /* We don't declare an inheriting ctor that would be a default,
3075 copy or move ctor for derived or base. */
3079 && TREE_CODE (parms
[0]) == REFERENCE_TYPE
)
3081 tree parm
= TYPE_MAIN_VARIANT (TREE_TYPE (parms
[0]));
3082 if (parm
== t
|| parm
== DECL_CONTEXT (ctor
))
3086 tree parmlist
= void_list_node
;
3087 for (int i
= nparms
- 1; i
>= 0; i
--)
3088 parmlist
= tree_cons (NULL_TREE
, parms
[i
], parmlist
);
3089 tree fn
= implicitly_declare_fn (sfk_inheriting_constructor
,
3090 t
, false, ctor
, parmlist
);
3092 if (add_method (t
, fn
, false))
3094 DECL_CHAIN (fn
) = TYPE_FIELDS (t
);
3095 TYPE_FIELDS (t
) = fn
;
3099 /* Declare all the inheriting constructors for class T inherited from base
3100 constructor CTOR. */
3103 one_inherited_ctor (tree ctor
, tree t
, tree using_decl
)
3105 tree parms
= FUNCTION_FIRST_USER_PARMTYPE (ctor
);
3107 if (flag_new_inheriting_ctors
)
3109 ctor
= implicitly_declare_fn (sfk_inheriting_constructor
,
3110 t
, /*const*/false, ctor
, parms
);
3111 add_method (t
, ctor
, using_decl
!= NULL_TREE
);
3112 TYPE_HAS_USER_CONSTRUCTOR (t
) = true;
3116 tree
*new_parms
= XALLOCAVEC (tree
, list_length (parms
));
3118 for (; parms
&& parms
!= void_list_node
; parms
= TREE_CHAIN (parms
))
3120 if (TREE_PURPOSE (parms
))
3121 one_inheriting_sig (t
, ctor
, new_parms
, i
);
3122 new_parms
[i
++] = TREE_VALUE (parms
);
3124 one_inheriting_sig (t
, ctor
, new_parms
, i
);
3125 if (parms
== NULL_TREE
)
3127 if (warning (OPT_Winherited_variadic_ctor
,
3128 "the ellipsis in %qD is not inherited", ctor
))
3129 inform (DECL_SOURCE_LOCATION (ctor
), "%qD declared here", ctor
);
3133 /* Create default constructors, assignment operators, and so forth for
3134 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
3135 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
3136 the class cannot have a default constructor, copy constructor
3137 taking a const reference argument, or an assignment operator taking
3138 a const reference, respectively. */
3141 add_implicitly_declared_members (tree t
, tree
* access_decls
,
3142 int cant_have_const_cctor
,
3143 int cant_have_const_assignment
)
3146 if (!CLASSTYPE_DESTRUCTOR (t
))
3147 /* In general, we create destructors lazily. */
3148 CLASSTYPE_LAZY_DESTRUCTOR (t
) = 1;
3150 bool move_ok
= false;
3151 if (cxx_dialect
>= cxx11
&& CLASSTYPE_LAZY_DESTRUCTOR (t
)
3152 && !TYPE_HAS_COPY_CTOR (t
) && !TYPE_HAS_COPY_ASSIGN (t
)
3153 && !classtype_has_move_assign_or_move_ctor_p (t
, false))
3158 If there is no user-declared constructor for a class, a default
3159 constructor is implicitly declared. */
3160 if (! TYPE_HAS_USER_CONSTRUCTOR (t
))
3162 TYPE_HAS_DEFAULT_CONSTRUCTOR (t
) = 1;
3163 CLASSTYPE_LAZY_DEFAULT_CTOR (t
) = 1;
3164 if (cxx_dialect
>= cxx11
)
3165 TYPE_HAS_CONSTEXPR_CTOR (t
)
3166 /* Don't force the declaration to get a hard answer; if the
3167 definition would have made the class non-literal, it will still be
3168 non-literal because of the base or member in question, and that
3169 gives a better diagnostic. */
3170 = type_maybe_constexpr_default_constructor (t
);
3175 If a class definition does not explicitly declare a copy
3176 constructor, one is declared implicitly. */
3177 if (! TYPE_HAS_COPY_CTOR (t
))
3179 TYPE_HAS_COPY_CTOR (t
) = 1;
3180 TYPE_HAS_CONST_COPY_CTOR (t
) = !cant_have_const_cctor
;
3181 CLASSTYPE_LAZY_COPY_CTOR (t
) = 1;
3183 CLASSTYPE_LAZY_MOVE_CTOR (t
) = 1;
3186 /* If there is no assignment operator, one will be created if and
3187 when it is needed. For now, just record whether or not the type
3188 of the parameter to the assignment operator will be a const or
3189 non-const reference. */
3190 if (!TYPE_HAS_COPY_ASSIGN (t
))
3192 TYPE_HAS_COPY_ASSIGN (t
) = 1;
3193 TYPE_HAS_CONST_COPY_ASSIGN (t
) = !cant_have_const_assignment
;
3194 CLASSTYPE_LAZY_COPY_ASSIGN (t
) = 1;
3195 if (move_ok
&& !LAMBDA_TYPE_P (t
))
3196 CLASSTYPE_LAZY_MOVE_ASSIGN (t
) = 1;
3199 /* We can't be lazy about declaring functions that might override
3200 a virtual function from a base class. */
3201 declare_virt_assop_and_dtor (t
);
3203 while (*access_decls
)
3205 tree using_decl
= TREE_VALUE (*access_decls
);
3206 tree decl
= USING_DECL_DECLS (using_decl
);
3207 if (DECL_NAME (using_decl
) == ctor_identifier
)
3209 /* declare, then remove the decl */
3210 tree ctor_list
= decl
;
3211 location_t loc
= input_location
;
3212 input_location
= DECL_SOURCE_LOCATION (using_decl
);
3213 for (ovl_iterator
iter (ctor_list
); iter
; ++iter
)
3214 one_inherited_ctor (*iter
, t
, using_decl
);
3215 *access_decls
= TREE_CHAIN (*access_decls
);
3216 input_location
= loc
;
3219 access_decls
= &TREE_CHAIN (*access_decls
);
3223 /* FIELD is a bit-field. We are finishing the processing for its
3224 enclosing type. Issue any appropriate messages and set appropriate
3225 flags. Returns false if an error has been diagnosed. */
3228 check_bitfield_decl (tree field
)
3230 tree type
= TREE_TYPE (field
);
3233 /* Extract the declared width of the bitfield, which has been
3234 temporarily stashed in DECL_INITIAL. */
3235 w
= DECL_INITIAL (field
);
3236 gcc_assert (w
!= NULL_TREE
);
3237 /* Remove the bit-field width indicator so that the rest of the
3238 compiler does not treat that value as an initializer. */
3239 DECL_INITIAL (field
) = NULL_TREE
;
3241 /* Detect invalid bit-field type. */
3242 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type
))
3244 error ("bit-field %q+#D with non-integral type", field
);
3245 w
= error_mark_node
;
3249 location_t loc
= input_location
;
3250 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
3253 /* detect invalid field size. */
3254 input_location
= DECL_SOURCE_LOCATION (field
);
3255 w
= cxx_constant_value (w
);
3256 input_location
= loc
;
3258 if (TREE_CODE (w
) != INTEGER_CST
)
3260 error ("bit-field %q+D width not an integer constant", field
);
3261 w
= error_mark_node
;
3263 else if (tree_int_cst_sgn (w
) < 0)
3265 error ("negative width in bit-field %q+D", field
);
3266 w
= error_mark_node
;
3268 else if (integer_zerop (w
) && DECL_NAME (field
) != 0)
3270 error ("zero width for bit-field %q+D", field
);
3271 w
= error_mark_node
;
3273 else if ((TREE_CODE (type
) != ENUMERAL_TYPE
3274 && TREE_CODE (type
) != BOOLEAN_TYPE
3275 && compare_tree_int (w
, TYPE_PRECISION (type
)) > 0)
3276 || ((TREE_CODE (type
) == ENUMERAL_TYPE
3277 || TREE_CODE (type
) == BOOLEAN_TYPE
)
3278 && tree_int_cst_lt (TYPE_SIZE (type
), w
)))
3279 warning_at (DECL_SOURCE_LOCATION (field
), 0,
3280 "width of %qD exceeds its type", field
);
3281 else if (TREE_CODE (type
) == ENUMERAL_TYPE
3282 && (0 > (compare_tree_int
3283 (w
, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type
))))))
3284 warning_at (DECL_SOURCE_LOCATION (field
), 0,
3285 "%qD is too small to hold all values of %q#T",
3289 if (w
!= error_mark_node
)
3291 DECL_SIZE (field
) = fold_convert (bitsizetype
, w
);
3292 DECL_BIT_FIELD (field
) = 1;
3297 /* Non-bit-fields are aligned for their type. */
3298 DECL_BIT_FIELD (field
) = 0;
3299 CLEAR_DECL_C_BIT_FIELD (field
);
3304 /* FIELD is a non bit-field. We are finishing the processing for its
3305 enclosing type T. Issue any appropriate messages and set appropriate
3309 check_field_decl (tree field
,
3311 int* cant_have_const_ctor
,
3312 int* no_const_asn_ref
)
3314 tree type
= strip_array_types (TREE_TYPE (field
));
3315 bool any_default_members
= false;
3317 /* In C++98 an anonymous union cannot contain any fields which would change
3318 the settings of CANT_HAVE_CONST_CTOR and friends. */
3319 if (ANON_UNION_TYPE_P (type
) && cxx_dialect
< cxx11
)
3321 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
3322 structs. So, we recurse through their fields here. */
3323 else if (ANON_AGGR_TYPE_P (type
))
3325 for (tree fields
= TYPE_FIELDS (type
); fields
;
3326 fields
= DECL_CHAIN (fields
))
3327 if (TREE_CODE (fields
) == FIELD_DECL
&& !DECL_C_BIT_FIELD (field
))
3328 any_default_members
|= check_field_decl (fields
, t
,
3329 cant_have_const_ctor
,
3332 /* Check members with class type for constructors, destructors,
3334 else if (CLASS_TYPE_P (type
))
3336 /* Never let anything with uninheritable virtuals
3337 make it through without complaint. */
3338 abstract_virtuals_error (field
, type
);
3340 if (TREE_CODE (t
) == UNION_TYPE
&& cxx_dialect
< cxx11
)
3343 int oldcount
= errorcount
;
3344 if (TYPE_NEEDS_CONSTRUCTING (type
))
3345 error ("member %q+#D with constructor not allowed in union",
3347 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
3348 error ("member %q+#D with destructor not allowed in union", field
);
3349 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type
))
3350 error ("member %q+#D with copy assignment operator not allowed in union",
3352 if (!warned
&& errorcount
> oldcount
)
3354 inform (DECL_SOURCE_LOCATION (field
), "unrestricted unions "
3355 "only available with -std=c++11 or -std=gnu++11");
3361 TYPE_NEEDS_CONSTRUCTING (t
) |= TYPE_NEEDS_CONSTRUCTING (type
);
3362 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t
)
3363 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
);
3364 TYPE_HAS_COMPLEX_COPY_ASSIGN (t
)
3365 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type
)
3366 || !TYPE_HAS_COPY_ASSIGN (type
));
3367 TYPE_HAS_COMPLEX_COPY_CTOR (t
) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type
)
3368 || !TYPE_HAS_COPY_CTOR (type
));
3369 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t
) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type
);
3370 TYPE_HAS_COMPLEX_MOVE_CTOR (t
) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type
);
3371 TYPE_HAS_COMPLEX_DFLT (t
) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type
)
3372 || TYPE_HAS_COMPLEX_DFLT (type
));
3375 if (TYPE_HAS_COPY_CTOR (type
)
3376 && !TYPE_HAS_CONST_COPY_CTOR (type
))
3377 *cant_have_const_ctor
= 1;
3379 if (TYPE_HAS_COPY_ASSIGN (type
)
3380 && !TYPE_HAS_CONST_COPY_ASSIGN (type
))
3381 *no_const_asn_ref
= 1;
3384 check_abi_tags (t
, field
);
3386 if (DECL_INITIAL (field
) != NULL_TREE
)
3387 /* `build_class_init_list' does not recognize
3389 any_default_members
= true;
3391 return any_default_members
;
3394 /* Check the data members (both static and non-static), class-scoped
3395 typedefs, etc., appearing in the declaration of T. Issue
3396 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
3397 declaration order) of access declarations; each TREE_VALUE in this
3398 list is a USING_DECL.
3400 In addition, set the following flags:
3403 The class is empty, i.e., contains no non-static data members.
3405 CANT_HAVE_CONST_CTOR_P
3406 This class cannot have an implicitly generated copy constructor
3407 taking a const reference.
3409 CANT_HAVE_CONST_ASN_REF
3410 This class cannot have an implicitly generated assignment
3411 operator taking a const reference.
3413 All of these flags should be initialized before calling this
3416 Returns a pointer to the end of the TYPE_FIELDs chain; additional
3417 fields can be added by adding to this chain. */
3420 check_field_decls (tree t
, tree
*access_decls
,
3421 int *cant_have_const_ctor_p
,
3422 int *no_const_asn_ref_p
)
3427 bool any_default_members
;
3429 int field_access
= -1;
3431 /* Assume there are no access declarations. */
3432 *access_decls
= NULL_TREE
;
3433 /* Assume this class has no pointer members. */
3434 has_pointers
= false;
3435 /* Assume none of the members of this class have default
3437 any_default_members
= false;
3439 for (field
= &TYPE_FIELDS (t
); *field
; field
= next
)
3442 tree type
= TREE_TYPE (x
);
3443 int this_field_access
;
3445 next
= &DECL_CHAIN (x
);
3447 if (TREE_CODE (x
) == USING_DECL
)
3449 /* Save the access declarations for our caller. */
3450 *access_decls
= tree_cons (NULL_TREE
, x
, *access_decls
);
3454 if (TREE_CODE (x
) == TYPE_DECL
3455 || TREE_CODE (x
) == TEMPLATE_DECL
)
3458 if (TREE_CODE (x
) == FUNCTION_DECL
)
3459 /* FIXME: We should fold in the checking from check_methods. */
3462 /* If we've gotten this far, it's a data member, possibly static,
3463 or an enumerator. */
3464 if (TREE_CODE (x
) != CONST_DECL
)
3465 DECL_CONTEXT (x
) = t
;
3467 /* When this goes into scope, it will be a non-local reference. */
3468 DECL_NONLOCAL (x
) = 1;
3470 if (TREE_CODE (t
) == UNION_TYPE
)
3472 /* [class.union] (C++98)
3474 If a union contains a static data member, or a member of
3475 reference type, the program is ill-formed.
3477 In C++11 [class.union] says:
3478 If a union contains a non-static data member of reference type
3479 the program is ill-formed. */
3480 if (VAR_P (x
) && cxx_dialect
< cxx11
)
3482 error ("in C++98 %q+D may not be static because it is "
3483 "a member of a union", x
);
3486 if (TREE_CODE (type
) == REFERENCE_TYPE
3487 && TREE_CODE (x
) == FIELD_DECL
)
3489 error ("non-static data member %q+D in a union may not "
3490 "have reference type %qT", x
, type
);
3495 /* Perform error checking that did not get done in
3497 if (TREE_CODE (type
) == FUNCTION_TYPE
)
3499 error ("field %q+D invalidly declared function type", x
);
3500 type
= build_pointer_type (type
);
3501 TREE_TYPE (x
) = type
;
3503 else if (TREE_CODE (type
) == METHOD_TYPE
)
3505 error ("field %q+D invalidly declared method type", x
);
3506 type
= build_pointer_type (type
);
3507 TREE_TYPE (x
) = type
;
3510 if (type
== error_mark_node
)
3513 if (TREE_CODE (x
) == CONST_DECL
|| VAR_P (x
))
3516 /* Now it can only be a FIELD_DECL. */
3518 if (TREE_PRIVATE (x
) || TREE_PROTECTED (x
))
3519 CLASSTYPE_NON_AGGREGATE (t
) = 1;
3521 /* If at least one non-static data member is non-literal, the whole
3522 class becomes non-literal. Per Core/1453, volatile non-static
3523 data members and base classes are also not allowed.
3524 Note: if the type is incomplete we will complain later on. */
3525 if (COMPLETE_TYPE_P (type
)
3526 && (!literal_type_p (type
) || CP_TYPE_VOLATILE_P (type
)))
3527 CLASSTYPE_LITERAL_P (t
) = false;
3529 /* A standard-layout class is a class that:
3531 has the same access control (Clause 11) for all non-static data members,
3533 this_field_access
= TREE_PROTECTED (x
) ? 1 : TREE_PRIVATE (x
) ? 2 : 0;
3534 if (field_access
== -1)
3535 field_access
= this_field_access
;
3536 else if (this_field_access
!= field_access
)
3537 CLASSTYPE_NON_STD_LAYOUT (t
) = 1;
3539 /* If this is of reference type, check if it needs an init. */
3540 if (TREE_CODE (type
) == REFERENCE_TYPE
)
3542 CLASSTYPE_NON_LAYOUT_POD_P (t
) = 1;
3543 CLASSTYPE_NON_STD_LAYOUT (t
) = 1;
3544 if (DECL_INITIAL (x
) == NULL_TREE
)
3545 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t
, 1);
3546 if (cxx_dialect
< cxx11
)
3548 /* ARM $12.6.2: [A member initializer list] (or, for an
3549 aggregate, initialization by a brace-enclosed list) is the
3550 only way to initialize nonstatic const and reference
3552 TYPE_HAS_COMPLEX_COPY_ASSIGN (t
) = 1;
3553 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t
) = 1;
3557 type
= strip_array_types (type
);
3559 if (TYPE_PACKED (t
))
3561 if (!layout_pod_type_p (type
) && !TYPE_PACKED (type
))
3564 (DECL_SOURCE_LOCATION (x
), 0,
3565 "ignoring packed attribute because of unpacked non-POD field %q#D",
3569 else if (DECL_C_BIT_FIELD (x
)
3570 || TYPE_ALIGN (TREE_TYPE (x
)) > BITS_PER_UNIT
)
3571 DECL_PACKED (x
) = 1;
3574 if (DECL_C_BIT_FIELD (x
) && integer_zerop (DECL_INITIAL (x
)))
3575 /* We don't treat zero-width bitfields as making a class
3580 /* The class is non-empty. */
3581 CLASSTYPE_EMPTY_P (t
) = 0;
3582 /* The class is not even nearly empty. */
3583 CLASSTYPE_NEARLY_EMPTY_P (t
) = 0;
3584 /* If one of the data members contains an empty class,
3586 if (CLASS_TYPE_P (type
)
3587 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type
))
3588 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t
) = 1;
3591 /* This is used by -Weffc++ (see below). Warn only for pointers
3592 to members which might hold dynamic memory. So do not warn
3593 for pointers to functions or pointers to members. */
3594 if (TYPE_PTR_P (type
)
3595 && !TYPE_PTRFN_P (type
))
3596 has_pointers
= true;
3598 if (CLASS_TYPE_P (type
))
3600 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type
))
3601 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t
, 1);
3602 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type
))
3603 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t
, 1);
3606 if (DECL_MUTABLE_P (x
) || TYPE_HAS_MUTABLE_P (type
))
3607 CLASSTYPE_HAS_MUTABLE (t
) = 1;
3609 if (DECL_MUTABLE_P (x
))
3611 if (CP_TYPE_CONST_P (type
))
3613 error ("member %q+D cannot be declared both %<const%> "
3614 "and %<mutable%>", x
);
3617 if (TREE_CODE (type
) == REFERENCE_TYPE
)
3619 error ("member %q+D cannot be declared as a %<mutable%> "
3625 if (! layout_pod_type_p (type
))
3626 /* DR 148 now allows pointers to members (which are POD themselves),
3627 to be allowed in POD structs. */
3628 CLASSTYPE_NON_LAYOUT_POD_P (t
) = 1;
3630 if (!std_layout_type_p (type
))
3631 CLASSTYPE_NON_STD_LAYOUT (t
) = 1;
3633 if (! zero_init_p (type
))
3634 CLASSTYPE_NON_ZERO_INIT_P (t
) = 1;
3636 /* We set DECL_C_BIT_FIELD in grokbitfield.
3637 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3638 if ((! DECL_C_BIT_FIELD (x
) || ! check_bitfield_decl (x
))
3639 && check_field_decl (x
, t
,
3640 cant_have_const_ctor_p
,
3641 no_const_asn_ref_p
))
3643 if (any_default_members
3644 && TREE_CODE (t
) == UNION_TYPE
)
3645 error ("multiple fields in union %qT initialized", t
);
3646 any_default_members
= true;
3649 /* Now that we've removed bit-field widths from DECL_INITIAL,
3650 anything left in DECL_INITIAL is an NSDMI that makes the class
3651 non-aggregate in C++11. */
3652 if (DECL_INITIAL (x
) && cxx_dialect
< cxx14
)
3653 CLASSTYPE_NON_AGGREGATE (t
) = true;
3655 /* If any field is const, the structure type is pseudo-const. */
3656 if (CP_TYPE_CONST_P (type
))
3658 C_TYPE_FIELDS_READONLY (t
) = 1;
3659 if (DECL_INITIAL (x
) == NULL_TREE
)
3660 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t
, 1);
3661 if (cxx_dialect
< cxx11
)
3663 /* ARM $12.6.2: [A member initializer list] (or, for an
3664 aggregate, initialization by a brace-enclosed list) is the
3665 only way to initialize nonstatic const and reference
3667 TYPE_HAS_COMPLEX_COPY_ASSIGN (t
) = 1;
3668 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t
) = 1;
3671 /* A field that is pseudo-const makes the structure likewise. */
3672 else if (CLASS_TYPE_P (type
))
3674 C_TYPE_FIELDS_READONLY (t
) |= C_TYPE_FIELDS_READONLY (type
);
3675 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t
,
3676 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t
)
3677 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type
));
3680 /* Core issue 80: A nonstatic data member is required to have a
3681 different name from the class iff the class has a
3682 user-declared constructor. */
3683 if (constructor_name_p (DECL_NAME (x
), t
)
3684 && TYPE_HAS_USER_CONSTRUCTOR (t
))
3685 permerror (DECL_SOURCE_LOCATION (x
),
3686 "field %q#D with same name as class", x
);
3689 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3690 it should also define a copy constructor and an assignment operator to
3691 implement the correct copy semantic (deep vs shallow, etc.). As it is
3692 not feasible to check whether the constructors do allocate dynamic memory
3693 and store it within members, we approximate the warning like this:
3695 -- Warn only if there are members which are pointers
3696 -- Warn only if there is a non-trivial constructor (otherwise,
3697 there cannot be memory allocated).
3698 -- Warn only if there is a non-trivial destructor. We assume that the
3699 user at least implemented the cleanup correctly, and a destructor
3700 is needed to free dynamic memory.
3702 This seems enough for practical purposes. */
3705 && TYPE_HAS_USER_CONSTRUCTOR (t
)
3706 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t
)
3707 && !(TYPE_HAS_COPY_CTOR (t
) && TYPE_HAS_COPY_ASSIGN (t
)))
3709 warning (OPT_Weffc__
, "%q#T has pointer data members", t
);
3711 if (! TYPE_HAS_COPY_CTOR (t
))
3713 warning (OPT_Weffc__
,
3714 " but does not override %<%T(const %T&)%>", t
, t
);
3715 if (!TYPE_HAS_COPY_ASSIGN (t
))
3716 warning (OPT_Weffc__
, " or %<operator=(const %T&)%>", t
);
3718 else if (! TYPE_HAS_COPY_ASSIGN (t
))
3719 warning (OPT_Weffc__
,
3720 " but does not override %<operator=(const %T&)%>", t
);
3723 /* Non-static data member initializers make the default constructor
3725 if (any_default_members
)
3727 TYPE_NEEDS_CONSTRUCTING (t
) = true;
3728 TYPE_HAS_COMPLEX_DFLT (t
) = true;
3731 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3733 TYPE_PACKED (t
) = 0;
3735 /* Check anonymous struct/anonymous union fields. */
3736 finish_struct_anon (t
);
3738 /* We've built up the list of access declarations in reverse order.
3740 *access_decls
= nreverse (*access_decls
);
3743 /* If TYPE is an empty class type, records its OFFSET in the table of
3747 record_subobject_offset (tree type
, tree offset
, splay_tree offsets
)
3751 if (!is_empty_class (type
))
3754 /* Record the location of this empty object in OFFSETS. */
3755 n
= splay_tree_lookup (offsets
, (splay_tree_key
) offset
);
3757 n
= splay_tree_insert (offsets
,
3758 (splay_tree_key
) offset
,
3759 (splay_tree_value
) NULL_TREE
);
3760 n
->value
= ((splay_tree_value
)
3761 tree_cons (NULL_TREE
,
3768 /* Returns nonzero if TYPE is an empty class type and there is
3769 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3772 check_subobject_offset (tree type
, tree offset
, splay_tree offsets
)
3777 if (!is_empty_class (type
))
3780 /* Record the location of this empty object in OFFSETS. */
3781 n
= splay_tree_lookup (offsets
, (splay_tree_key
) offset
);
3785 for (t
= (tree
) n
->value
; t
; t
= TREE_CHAIN (t
))
3786 if (same_type_p (TREE_VALUE (t
), type
))
3792 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3793 F for every subobject, passing it the type, offset, and table of
3794 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3797 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3798 than MAX_OFFSET will not be walked.
3800 If F returns a nonzero value, the traversal ceases, and that value
3801 is returned. Otherwise, returns zero. */
3804 walk_subobject_offsets (tree type
,
3805 subobject_offset_fn f
,
3812 tree type_binfo
= NULL_TREE
;
3814 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3816 if (max_offset
&& tree_int_cst_lt (max_offset
, offset
))
3819 if (type
== error_mark_node
)
3825 type
= BINFO_TYPE (type
);
3828 if (CLASS_TYPE_P (type
))
3834 /* Avoid recursing into objects that are not interesting. */
3835 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type
))
3838 /* Record the location of TYPE. */
3839 r
= (*f
) (type
, offset
, offsets
);
3843 /* Iterate through the direct base classes of TYPE. */
3845 type_binfo
= TYPE_BINFO (type
);
3846 for (i
= 0; BINFO_BASE_ITERATE (type_binfo
, i
, binfo
); i
++)
3850 if (BINFO_VIRTUAL_P (binfo
))
3854 /* We cannot rely on BINFO_OFFSET being set for the base
3855 class yet, but the offsets for direct non-virtual
3856 bases can be calculated by going back to the TYPE. */
3857 orig_binfo
= BINFO_BASE_BINFO (TYPE_BINFO (type
), i
);
3858 binfo_offset
= size_binop (PLUS_EXPR
,
3860 BINFO_OFFSET (orig_binfo
));
3862 r
= walk_subobject_offsets (binfo
,
3872 if (CLASSTYPE_VBASECLASSES (type
))
3875 vec
<tree
, va_gc
> *vbases
;
3877 /* Iterate through the virtual base classes of TYPE. In G++
3878 3.2, we included virtual bases in the direct base class
3879 loop above, which results in incorrect results; the
3880 correct offsets for virtual bases are only known when
3881 working with the most derived type. */
3883 for (vbases
= CLASSTYPE_VBASECLASSES (type
), ix
= 0;
3884 vec_safe_iterate (vbases
, ix
, &binfo
); ix
++)
3886 r
= walk_subobject_offsets (binfo
,
3888 size_binop (PLUS_EXPR
,
3890 BINFO_OFFSET (binfo
)),
3899 /* We still have to walk the primary base, if it is
3900 virtual. (If it is non-virtual, then it was walked
3902 tree vbase
= get_primary_binfo (type_binfo
);
3904 if (vbase
&& BINFO_VIRTUAL_P (vbase
)
3905 && BINFO_PRIMARY_P (vbase
)
3906 && BINFO_INHERITANCE_CHAIN (vbase
) == type_binfo
)
3908 r
= (walk_subobject_offsets
3910 offsets
, max_offset
, /*vbases_p=*/0));
3917 /* Iterate through the fields of TYPE. */
3918 for (field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
3919 if (TREE_CODE (field
) == FIELD_DECL
3920 && TREE_TYPE (field
) != error_mark_node
3921 && !DECL_ARTIFICIAL (field
))
3925 field_offset
= byte_position (field
);
3927 r
= walk_subobject_offsets (TREE_TYPE (field
),
3929 size_binop (PLUS_EXPR
,
3939 else if (TREE_CODE (type
) == ARRAY_TYPE
)
3941 tree element_type
= strip_array_types (type
);
3942 tree domain
= TYPE_DOMAIN (type
);
3945 /* Avoid recursing into objects that are not interesting. */
3946 if (!CLASS_TYPE_P (element_type
)
3947 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type
)
3949 || integer_minus_onep (TYPE_MAX_VALUE (domain
)))
3952 /* Step through each of the elements in the array. */
3953 for (index
= size_zero_node
;
3954 !tree_int_cst_lt (TYPE_MAX_VALUE (domain
), index
);
3955 index
= size_binop (PLUS_EXPR
, index
, size_one_node
))
3957 r
= walk_subobject_offsets (TREE_TYPE (type
),
3965 offset
= size_binop (PLUS_EXPR
, offset
,
3966 TYPE_SIZE_UNIT (TREE_TYPE (type
)));
3967 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3968 there's no point in iterating through the remaining
3969 elements of the array. */
3970 if (max_offset
&& tree_int_cst_lt (max_offset
, offset
))
3978 /* Record all of the empty subobjects of TYPE (either a type or a
3979 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3980 is being placed at OFFSET; otherwise, it is a base class that is
3981 being placed at OFFSET. */
3984 record_subobject_offsets (tree type
,
3987 bool is_data_member
)
3990 /* If recording subobjects for a non-static data member or a
3991 non-empty base class , we do not need to record offsets beyond
3992 the size of the biggest empty class. Additional data members
3993 will go at the end of the class. Additional base classes will go
3994 either at offset zero (if empty, in which case they cannot
3995 overlap with offsets past the size of the biggest empty class) or
3996 at the end of the class.
3998 However, if we are placing an empty base class, then we must record
3999 all offsets, as either the empty class is at offset zero (where
4000 other empty classes might later be placed) or at the end of the
4001 class (where other objects might then be placed, so other empty
4002 subobjects might later overlap). */
4004 || !is_empty_class (BINFO_TYPE (type
)))
4005 max_offset
= sizeof_biggest_empty_class
;
4007 max_offset
= NULL_TREE
;
4008 walk_subobject_offsets (type
, record_subobject_offset
, offset
,
4009 offsets
, max_offset
, is_data_member
);
4012 /* Returns nonzero if any of the empty subobjects of TYPE (located at
4013 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
4014 virtual bases of TYPE are examined. */
4017 layout_conflict_p (tree type
,
4022 splay_tree_node max_node
;
4024 /* Get the node in OFFSETS that indicates the maximum offset where
4025 an empty subobject is located. */
4026 max_node
= splay_tree_max (offsets
);
4027 /* If there aren't any empty subobjects, then there's no point in
4028 performing this check. */
4032 return walk_subobject_offsets (type
, check_subobject_offset
, offset
,
4033 offsets
, (tree
) (max_node
->key
),
4037 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
4038 non-static data member of the type indicated by RLI. BINFO is the
4039 binfo corresponding to the base subobject, OFFSETS maps offsets to
4040 types already located at those offsets. This function determines
4041 the position of the DECL. */
4044 layout_nonempty_base_or_field (record_layout_info rli
,
4049 tree offset
= NULL_TREE
;
4055 /* For the purposes of determining layout conflicts, we want to
4056 use the class type of BINFO; TREE_TYPE (DECL) will be the
4057 CLASSTYPE_AS_BASE version, which does not contain entries for
4058 zero-sized bases. */
4059 type
= TREE_TYPE (binfo
);
4064 type
= TREE_TYPE (decl
);
4068 /* Try to place the field. It may take more than one try if we have
4069 a hard time placing the field without putting two objects of the
4070 same type at the same address. */
4073 struct record_layout_info_s old_rli
= *rli
;
4075 /* Place this field. */
4076 place_field (rli
, decl
);
4077 offset
= byte_position (decl
);
4079 /* We have to check to see whether or not there is already
4080 something of the same type at the offset we're about to use.
4081 For example, consider:
4084 struct T : public S { int i; };
4085 struct U : public S, public T {};
4087 Here, we put S at offset zero in U. Then, we can't put T at
4088 offset zero -- its S component would be at the same address
4089 as the S we already allocated. So, we have to skip ahead.
4090 Since all data members, including those whose type is an
4091 empty class, have nonzero size, any overlap can happen only
4092 with a direct or indirect base-class -- it can't happen with
4094 /* In a union, overlap is permitted; all members are placed at
4096 if (TREE_CODE (rli
->t
) == UNION_TYPE
)
4098 if (layout_conflict_p (field_p
? type
: binfo
, offset
,
4101 /* Strip off the size allocated to this field. That puts us
4102 at the first place we could have put the field with
4103 proper alignment. */
4106 /* Bump up by the alignment required for the type. */
4108 = size_binop (PLUS_EXPR
, rli
->bitpos
,
4110 ? CLASSTYPE_ALIGN (type
)
4111 : TYPE_ALIGN (type
)));
4112 normalize_rli (rli
);
4114 else if (TREE_CODE (type
) == NULLPTR_TYPE
4115 && warn_abi
&& abi_version_crosses (9))
4117 /* Before ABI v9, we were giving nullptr_t alignment of 1; if
4118 the offset wasn't aligned like a pointer when we started to
4119 layout this field, that affects its position. */
4120 tree pos
= rli_size_unit_so_far (&old_rli
);
4121 if (int_cst_value (pos
) % TYPE_ALIGN_UNIT (ptr_type_node
) != 0)
4123 if (abi_version_at_least (9))
4124 warning_at (DECL_SOURCE_LOCATION (decl
), OPT_Wabi
,
4125 "alignment of %qD increased in -fabi-version=9 "
4128 warning_at (DECL_SOURCE_LOCATION (decl
), OPT_Wabi
, "alignment "
4129 "of %qD will increase in -fabi-version=9", decl
);
4134 /* There was no conflict. We're done laying out this field. */
4138 /* Now that we know where it will be placed, update its
4140 if (binfo
&& CLASS_TYPE_P (BINFO_TYPE (binfo
)))
4141 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
4142 this point because their BINFO_OFFSET is copied from another
4143 hierarchy. Therefore, we may not need to add the entire
4145 propagate_binfo_offsets (binfo
,
4146 size_diffop_loc (input_location
,
4147 fold_convert (ssizetype
, offset
),
4148 fold_convert (ssizetype
,
4149 BINFO_OFFSET (binfo
))));
4152 /* Returns true if TYPE is empty and OFFSET is nonzero. */
4155 empty_base_at_nonzero_offset_p (tree type
,
4157 splay_tree
/*offsets*/)
4159 return is_empty_class (type
) && !integer_zerop (offset
);
4162 /* Layout the empty base BINFO. EOC indicates the byte currently just
4163 past the end of the class, and should be correctly aligned for a
4164 class of the type indicated by BINFO; OFFSETS gives the offsets of
4165 the empty bases allocated so far. T is the most derived
4166 type. Return nonzero iff we added it at the end. */
4169 layout_empty_base (record_layout_info rli
, tree binfo
,
4170 tree eoc
, splay_tree offsets
)
4173 tree basetype
= BINFO_TYPE (binfo
);
4176 /* This routine should only be used for empty classes. */
4177 gcc_assert (is_empty_class (basetype
));
4178 alignment
= ssize_int (CLASSTYPE_ALIGN_UNIT (basetype
));
4180 if (!integer_zerop (BINFO_OFFSET (binfo
)))
4181 propagate_binfo_offsets
4182 (binfo
, size_diffop_loc (input_location
,
4183 size_zero_node
, BINFO_OFFSET (binfo
)));
4185 /* This is an empty base class. We first try to put it at offset
4187 if (layout_conflict_p (binfo
,
4188 BINFO_OFFSET (binfo
),
4192 /* That didn't work. Now, we move forward from the next
4193 available spot in the class. */
4195 propagate_binfo_offsets (binfo
, fold_convert (ssizetype
, eoc
));
4198 if (!layout_conflict_p (binfo
,
4199 BINFO_OFFSET (binfo
),
4202 /* We finally found a spot where there's no overlap. */
4205 /* There's overlap here, too. Bump along to the next spot. */
4206 propagate_binfo_offsets (binfo
, alignment
);
4210 if (CLASSTYPE_USER_ALIGN (basetype
))
4212 rli
->record_align
= MAX (rli
->record_align
, CLASSTYPE_ALIGN (basetype
));
4214 rli
->unpacked_align
= MAX (rli
->unpacked_align
, CLASSTYPE_ALIGN (basetype
));
4215 TYPE_USER_ALIGN (rli
->t
) = 1;
4221 /* Build the FIELD_DECL for BASETYPE as a base of T, add it to the chain of
4222 fields at NEXT_FIELD, and return it. */
4225 build_base_field_1 (tree t
, tree basetype
, tree
*&next_field
)
4227 /* Create the FIELD_DECL. */
4228 gcc_assert (CLASSTYPE_AS_BASE (basetype
));
4229 tree decl
= build_decl (input_location
,
4230 FIELD_DECL
, NULL_TREE
, CLASSTYPE_AS_BASE (basetype
));
4231 DECL_ARTIFICIAL (decl
) = 1;
4232 DECL_IGNORED_P (decl
) = 1;
4233 DECL_FIELD_CONTEXT (decl
) = t
;
4234 DECL_SIZE (decl
) = CLASSTYPE_SIZE (basetype
);
4235 DECL_SIZE_UNIT (decl
) = CLASSTYPE_SIZE_UNIT (basetype
);
4236 SET_DECL_ALIGN (decl
, CLASSTYPE_ALIGN (basetype
));
4237 DECL_USER_ALIGN (decl
) = CLASSTYPE_USER_ALIGN (basetype
);
4238 SET_DECL_MODE (decl
, TYPE_MODE (basetype
));
4239 DECL_FIELD_IS_BASE (decl
) = 1;
4241 /* Add the new FIELD_DECL to the list of fields for T. */
4242 DECL_CHAIN (decl
) = *next_field
;
4244 next_field
= &DECL_CHAIN (decl
);
4249 /* Layout the base given by BINFO in the class indicated by RLI.
4250 *BASE_ALIGN is a running maximum of the alignments of
4251 any base class. OFFSETS gives the location of empty base
4252 subobjects. T is the most derived type. Return nonzero if the new
4253 object cannot be nearly-empty. A new FIELD_DECL is inserted at
4254 *NEXT_FIELD, unless BINFO is for an empty base class.
4256 Returns the location at which the next field should be inserted. */
4259 build_base_field (record_layout_info rli
, tree binfo
,
4260 splay_tree offsets
, tree
*next_field
)
4263 tree basetype
= BINFO_TYPE (binfo
);
4265 if (!COMPLETE_TYPE_P (basetype
))
4266 /* This error is now reported in xref_tag, thus giving better
4267 location information. */
4270 /* Place the base class. */
4271 if (!is_empty_class (basetype
))
4275 /* The containing class is non-empty because it has a non-empty
4277 CLASSTYPE_EMPTY_P (t
) = 0;
4279 /* Create the FIELD_DECL. */
4280 decl
= build_base_field_1 (t
, basetype
, next_field
);
4282 /* Try to place the field. It may take more than one try if we
4283 have a hard time placing the field without putting two
4284 objects of the same type at the same address. */
4285 layout_nonempty_base_or_field (rli
, decl
, binfo
, offsets
);
4292 /* On some platforms (ARM), even empty classes will not be
4294 eoc
= round_up_loc (input_location
,
4295 rli_size_unit_so_far (rli
),
4296 CLASSTYPE_ALIGN_UNIT (basetype
));
4297 atend
= layout_empty_base (rli
, binfo
, eoc
, offsets
);
4298 /* A nearly-empty class "has no proper base class that is empty,
4299 not morally virtual, and at an offset other than zero." */
4300 if (!BINFO_VIRTUAL_P (binfo
) && CLASSTYPE_NEARLY_EMPTY_P (t
))
4303 CLASSTYPE_NEARLY_EMPTY_P (t
) = 0;
4304 /* The check above (used in G++ 3.2) is insufficient because
4305 an empty class placed at offset zero might itself have an
4306 empty base at a nonzero offset. */
4307 else if (walk_subobject_offsets (basetype
,
4308 empty_base_at_nonzero_offset_p
,
4311 /*max_offset=*/NULL_TREE
,
4313 CLASSTYPE_NEARLY_EMPTY_P (t
) = 0;
4316 /* We used to not create a FIELD_DECL for empty base classes because of
4317 back end issues with overlapping FIELD_DECLs, but that doesn't seem to
4318 be a problem anymore. We need them to handle initialization of C++17
4320 if (cxx_dialect
>= cxx17
&& !BINFO_VIRTUAL_P (binfo
))
4322 tree decl
= build_base_field_1 (t
, basetype
, next_field
);
4323 DECL_FIELD_OFFSET (decl
) = BINFO_OFFSET (binfo
);
4324 DECL_FIELD_BIT_OFFSET (decl
) = bitsize_zero_node
;
4325 SET_DECL_OFFSET_ALIGN (decl
, BITS_PER_UNIT
);
4328 /* An empty virtual base causes a class to be non-empty
4329 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
4330 here because that was already done when the virtual table
4331 pointer was created. */
4334 /* Record the offsets of BINFO and its base subobjects. */
4335 record_subobject_offsets (binfo
,
4336 BINFO_OFFSET (binfo
),
4338 /*is_data_member=*/false);
4343 /* Layout all of the non-virtual base classes. Record empty
4344 subobjects in OFFSETS. T is the most derived type. Return nonzero
4345 if the type cannot be nearly empty. The fields created
4346 corresponding to the base classes will be inserted at
4350 build_base_fields (record_layout_info rli
,
4351 splay_tree offsets
, tree
*next_field
)
4353 /* Chain to hold all the new FIELD_DECLs which stand in for base class
4356 int n_baseclasses
= BINFO_N_BASE_BINFOS (TYPE_BINFO (t
));
4359 /* The primary base class is always allocated first. */
4360 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t
))
4361 next_field
= build_base_field (rli
, CLASSTYPE_PRIMARY_BINFO (t
),
4362 offsets
, next_field
);
4364 /* Now allocate the rest of the bases. */
4365 for (i
= 0; i
< n_baseclasses
; ++i
)
4369 base_binfo
= BINFO_BASE_BINFO (TYPE_BINFO (t
), i
);
4371 /* The primary base was already allocated above, so we don't
4372 need to allocate it again here. */
4373 if (base_binfo
== CLASSTYPE_PRIMARY_BINFO (t
))
4376 /* Virtual bases are added at the end (a primary virtual base
4377 will have already been added). */
4378 if (BINFO_VIRTUAL_P (base_binfo
))
4381 next_field
= build_base_field (rli
, base_binfo
,
4382 offsets
, next_field
);
4386 /* Go through the TYPE_FIELDS of T issuing any appropriate
4387 diagnostics, figuring out which methods override which other
4388 methods, and so forth. */
4391 check_methods (tree t
)
4393 for (tree x
= TYPE_FIELDS (t
); x
; x
= DECL_CHAIN (x
))
4394 if (DECL_DECLARES_FUNCTION_P (x
))
4396 check_for_override (x
, t
);
4398 if (DECL_PURE_VIRTUAL_P (x
)
4399 && (TREE_CODE (x
) != FUNCTION_DECL
|| ! DECL_VINDEX (x
)))
4400 error ("initializer specified for non-virtual method %q+D", x
);
4401 /* The name of the field is the original field name
4402 Save this in auxiliary field for later overloading. */
4403 if (TREE_CODE (x
) == FUNCTION_DECL
&& DECL_VINDEX (x
))
4405 TYPE_POLYMORPHIC_P (t
) = 1;
4406 if (DECL_PURE_VIRTUAL_P (x
))
4407 vec_safe_push (CLASSTYPE_PURE_VIRTUALS (t
), x
);
4410 /* All user-provided destructors are non-trivial.
4411 Constructors and assignment ops are handled in
4412 grok_special_member_properties. */
4413 if (DECL_DESTRUCTOR_P (x
) && user_provided_p (x
))
4414 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t
) = 1;
4415 if (!DECL_VIRTUAL_P (x
)
4416 && lookup_attribute ("transaction_safe_dynamic",
4417 DECL_ATTRIBUTES (x
)))
4418 error_at (DECL_SOURCE_LOCATION (x
),
4419 "%<transaction_safe_dynamic%> may only be specified for "
4420 "a virtual function");
4424 /* FN is a constructor or destructor. Clone the declaration to create
4425 a specialized in-charge or not-in-charge version, as indicated by
4429 build_clone (tree fn
, tree name
)
4434 /* Copy the function. */
4435 clone
= copy_decl (fn
);
4436 /* Reset the function name. */
4437 DECL_NAME (clone
) = name
;
4438 /* Remember where this function came from. */
4439 DECL_ABSTRACT_ORIGIN (clone
) = fn
;
4440 /* Make it easy to find the CLONE given the FN. */
4441 DECL_CHAIN (clone
) = DECL_CHAIN (fn
);
4442 DECL_CHAIN (fn
) = clone
;
4444 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
4445 if (TREE_CODE (clone
) == TEMPLATE_DECL
)
4447 tree result
= build_clone (DECL_TEMPLATE_RESULT (clone
), name
);
4448 DECL_TEMPLATE_RESULT (clone
) = result
;
4449 DECL_TEMPLATE_INFO (result
) = copy_node (DECL_TEMPLATE_INFO (result
));
4450 DECL_TI_TEMPLATE (result
) = clone
;
4451 TREE_TYPE (clone
) = TREE_TYPE (result
);
4456 // Clone constraints.
4458 if (tree ci
= get_constraints (fn
))
4459 set_constraints (clone
, copy_node (ci
));
4463 SET_DECL_ASSEMBLER_NAME (clone
, NULL_TREE
);
4464 DECL_CLONED_FUNCTION (clone
) = fn
;
4465 /* There's no pending inline data for this function. */
4466 DECL_PENDING_INLINE_INFO (clone
) = NULL
;
4467 DECL_PENDING_INLINE_P (clone
) = 0;
4469 /* The base-class destructor is not virtual. */
4470 if (name
== base_dtor_identifier
)
4472 DECL_VIRTUAL_P (clone
) = 0;
4473 if (TREE_CODE (clone
) != TEMPLATE_DECL
)
4474 DECL_VINDEX (clone
) = NULL_TREE
;
4477 bool ctor_omit_inherited_parms_p
= ctor_omit_inherited_parms (clone
);
4478 if (ctor_omit_inherited_parms_p
)
4479 gcc_assert (DECL_HAS_IN_CHARGE_PARM_P (clone
));
4481 /* If there was an in-charge parameter, drop it from the function
4483 if (DECL_HAS_IN_CHARGE_PARM_P (clone
))
4489 exceptions
= TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone
));
4490 basetype
= TYPE_METHOD_BASETYPE (TREE_TYPE (clone
));
4491 parmtypes
= TYPE_ARG_TYPES (TREE_TYPE (clone
));
4492 /* Skip the `this' parameter. */
4493 parmtypes
= TREE_CHAIN (parmtypes
);
4494 /* Skip the in-charge parameter. */
4495 parmtypes
= TREE_CHAIN (parmtypes
);
4496 /* And the VTT parm, in a complete [cd]tor. */
4497 if (DECL_HAS_VTT_PARM_P (fn
)
4498 && ! DECL_NEEDS_VTT_PARM_P (clone
))
4499 parmtypes
= TREE_CHAIN (parmtypes
);
4500 if (ctor_omit_inherited_parms_p
)
4502 /* If we're omitting inherited parms, that just leaves the VTT. */
4503 gcc_assert (DECL_NEEDS_VTT_PARM_P (clone
));
4504 parmtypes
= tree_cons (NULL_TREE
, vtt_parm_type
, void_list_node
);
4507 = build_method_type_directly (basetype
,
4508 TREE_TYPE (TREE_TYPE (clone
)),
4511 TREE_TYPE (clone
) = build_exception_variant (TREE_TYPE (clone
),
4514 = cp_build_type_attribute_variant (TREE_TYPE (clone
),
4515 TYPE_ATTRIBUTES (TREE_TYPE (fn
)));
4518 /* Copy the function parameters. */
4519 DECL_ARGUMENTS (clone
) = copy_list (DECL_ARGUMENTS (clone
));
4520 /* Remove the in-charge parameter. */
4521 if (DECL_HAS_IN_CHARGE_PARM_P (clone
))
4523 DECL_CHAIN (DECL_ARGUMENTS (clone
))
4524 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone
)));
4525 DECL_HAS_IN_CHARGE_PARM_P (clone
) = 0;
4527 /* And the VTT parm, in a complete [cd]tor. */
4528 if (DECL_HAS_VTT_PARM_P (fn
))
4530 if (DECL_NEEDS_VTT_PARM_P (clone
))
4531 DECL_HAS_VTT_PARM_P (clone
) = 1;
4534 DECL_CHAIN (DECL_ARGUMENTS (clone
))
4535 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone
)));
4536 DECL_HAS_VTT_PARM_P (clone
) = 0;
4540 /* A base constructor inheriting from a virtual base doesn't get the
4542 if (ctor_omit_inherited_parms_p
)
4543 DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone
))) = NULL_TREE
;
4545 for (parms
= DECL_ARGUMENTS (clone
); parms
; parms
= DECL_CHAIN (parms
))
4547 DECL_CONTEXT (parms
) = clone
;
4548 cxx_dup_lang_specific_decl (parms
);
4551 /* Create the RTL for this function. */
4552 SET_DECL_RTL (clone
, NULL
);
4553 rest_of_decl_compilation (clone
, /*top_level=*/1, at_eof
);
4558 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4559 not invoke this function directly.
4561 For a non-thunk function, returns the address of the slot for storing
4562 the function it is a clone of. Otherwise returns NULL_TREE.
4564 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4565 cloned_function is unset. This is to support the separate
4566 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4567 on a template makes sense, but not the former. */
4570 decl_cloned_function_p (const_tree decl
, bool just_testing
)
4574 decl
= STRIP_TEMPLATE (decl
);
4576 if (TREE_CODE (decl
) != FUNCTION_DECL
4577 || !DECL_LANG_SPECIFIC (decl
)
4578 || DECL_LANG_SPECIFIC (decl
)->u
.fn
.thunk_p
)
4580 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4582 lang_check_failed (__FILE__
, __LINE__
, __FUNCTION__
);
4588 ptr
= &DECL_LANG_SPECIFIC (decl
)->u
.fn
.u5
.cloned_function
;
4589 if (just_testing
&& *ptr
== NULL_TREE
)
4595 /* Produce declarations for all appropriate clones of FN. If
4596 UPDATE_METHODS is true, the clones are added to the
4597 CLASSTYPE_MEMBER_VEC. */
4600 clone_function_decl (tree fn
, bool update_methods
)
4604 /* Avoid inappropriate cloning. */
4606 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (fn
)))
4609 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
4611 /* For each constructor, we need two variants: an in-charge version
4612 and a not-in-charge version. */
4613 clone
= build_clone (fn
, complete_ctor_identifier
);
4615 add_method (DECL_CONTEXT (clone
), clone
, false);
4616 clone
= build_clone (fn
, base_ctor_identifier
);
4618 add_method (DECL_CONTEXT (clone
), clone
, false);
4622 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn
));
4624 /* For each destructor, we need three variants: an in-charge
4625 version, a not-in-charge version, and an in-charge deleting
4626 version. We clone the deleting version first because that
4627 means it will go second on the TYPE_FIELDS list -- and that
4628 corresponds to the correct layout order in the virtual
4631 For a non-virtual destructor, we do not build a deleting
4633 if (DECL_VIRTUAL_P (fn
))
4635 clone
= build_clone (fn
, deleting_dtor_identifier
);
4637 add_method (DECL_CONTEXT (clone
), clone
, false);
4639 clone
= build_clone (fn
, complete_dtor_identifier
);
4641 add_method (DECL_CONTEXT (clone
), clone
, false);
4642 clone
= build_clone (fn
, base_dtor_identifier
);
4644 add_method (DECL_CONTEXT (clone
), clone
, false);
4647 /* Note that this is an abstract function that is never emitted. */
4648 DECL_ABSTRACT_P (fn
) = true;
4651 /* DECL is an in charge constructor, which is being defined. This will
4652 have had an in class declaration, from whence clones were
4653 declared. An out-of-class definition can specify additional default
4654 arguments. As it is the clones that are involved in overload
4655 resolution, we must propagate the information from the DECL to its
4659 adjust_clone_args (tree decl
)
4663 for (clone
= DECL_CHAIN (decl
); clone
&& DECL_CLONED_FUNCTION_P (clone
);
4664 clone
= DECL_CHAIN (clone
))
4666 tree orig_clone_parms
= TYPE_ARG_TYPES (TREE_TYPE (clone
));
4667 tree orig_decl_parms
= TYPE_ARG_TYPES (TREE_TYPE (decl
));
4668 tree decl_parms
, clone_parms
;
4670 clone_parms
= orig_clone_parms
;
4672 /* Skip the 'this' parameter. */
4673 orig_clone_parms
= TREE_CHAIN (orig_clone_parms
);
4674 orig_decl_parms
= TREE_CHAIN (orig_decl_parms
);
4676 if (DECL_HAS_IN_CHARGE_PARM_P (decl
))
4677 orig_decl_parms
= TREE_CHAIN (orig_decl_parms
);
4678 if (DECL_HAS_VTT_PARM_P (decl
))
4679 orig_decl_parms
= TREE_CHAIN (orig_decl_parms
);
4681 clone_parms
= orig_clone_parms
;
4682 if (DECL_HAS_VTT_PARM_P (clone
))
4683 clone_parms
= TREE_CHAIN (clone_parms
);
4685 for (decl_parms
= orig_decl_parms
; decl_parms
;
4686 decl_parms
= TREE_CHAIN (decl_parms
),
4687 clone_parms
= TREE_CHAIN (clone_parms
))
4689 if (clone_parms
== void_list_node
)
4691 gcc_assert (decl_parms
== clone_parms
4692 || ctor_omit_inherited_parms (clone
));
4696 gcc_assert (same_type_p (TREE_TYPE (decl_parms
),
4697 TREE_TYPE (clone_parms
)));
4699 if (TREE_PURPOSE (decl_parms
) && !TREE_PURPOSE (clone_parms
))
4701 /* A default parameter has been added. Adjust the
4702 clone's parameters. */
4703 tree exceptions
= TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone
));
4704 tree attrs
= TYPE_ATTRIBUTES (TREE_TYPE (clone
));
4705 tree basetype
= TYPE_METHOD_BASETYPE (TREE_TYPE (clone
));
4708 clone_parms
= orig_decl_parms
;
4710 if (DECL_HAS_VTT_PARM_P (clone
))
4712 clone_parms
= tree_cons (TREE_PURPOSE (orig_clone_parms
),
4713 TREE_VALUE (orig_clone_parms
),
4715 TREE_TYPE (clone_parms
) = TREE_TYPE (orig_clone_parms
);
4717 type
= build_method_type_directly (basetype
,
4718 TREE_TYPE (TREE_TYPE (clone
)),
4721 type
= build_exception_variant (type
, exceptions
);
4723 type
= cp_build_type_attribute_variant (type
, attrs
);
4724 TREE_TYPE (clone
) = type
;
4726 clone_parms
= NULL_TREE
;
4730 gcc_assert (!clone_parms
|| clone_parms
== void_list_node
);
4734 /* For each of the constructors and destructors in T, create an
4735 in-charge and not-in-charge variant. */
4738 clone_constructors_and_destructors (tree t
)
4740 /* While constructors can be via a using declaration, at this point
4741 we no longer need to know that. */
4742 for (ovl_iterator
iter (CLASSTYPE_CONSTRUCTORS (t
)); iter
; ++iter
)
4743 clone_function_decl (*iter
, /*update_methods=*/true);
4745 if (tree dtor
= CLASSTYPE_DESTRUCTOR (t
))
4746 clone_function_decl (dtor
, /*update_methods=*/true);
4749 /* Deduce noexcept for a destructor DTOR. */
4752 deduce_noexcept_on_destructor (tree dtor
)
4754 if (!TYPE_RAISES_EXCEPTIONS (TREE_TYPE (dtor
)))
4755 TREE_TYPE (dtor
) = build_exception_variant (TREE_TYPE (dtor
),
4756 noexcept_deferred_spec
);
4759 /* Subroutine of set_one_vmethod_tm_attributes. Search base classes
4760 of TYPE for virtual functions which FNDECL overrides. Return a
4761 mask of the tm attributes found therein. */
4764 look_for_tm_attr_overrides (tree type
, tree fndecl
)
4766 tree binfo
= TYPE_BINFO (type
);
4770 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ++ix
)
4772 tree o
, basetype
= BINFO_TYPE (base_binfo
);
4774 if (!TYPE_POLYMORPHIC_P (basetype
))
4777 o
= look_for_overrides_here (basetype
, fndecl
);
4780 if (lookup_attribute ("transaction_safe_dynamic",
4781 DECL_ATTRIBUTES (o
)))
4782 /* transaction_safe_dynamic is not inherited. */;
4784 found
|= tm_attr_to_mask (find_tm_attribute
4785 (TYPE_ATTRIBUTES (TREE_TYPE (o
))));
4788 found
|= look_for_tm_attr_overrides (basetype
, fndecl
);
4794 /* Subroutine of set_method_tm_attributes. Handle the checks and
4795 inheritance for one virtual method FNDECL. */
4798 set_one_vmethod_tm_attributes (tree type
, tree fndecl
)
4803 found
= look_for_tm_attr_overrides (type
, fndecl
);
4805 /* If FNDECL doesn't actually override anything (i.e. T is the
4806 class that first declares FNDECL virtual), then we're done. */
4810 tm_attr
= find_tm_attribute (TYPE_ATTRIBUTES (TREE_TYPE (fndecl
)));
4811 have
= tm_attr_to_mask (tm_attr
);
4813 /* Intel STM Language Extension 3.0, Section 4.2 table 4:
4814 tm_pure must match exactly, otherwise no weakening of
4815 tm_safe > tm_callable > nothing. */
4816 /* ??? The tm_pure attribute didn't make the transition to the
4817 multivendor language spec. */
4818 if (have
== TM_ATTR_PURE
)
4820 if (found
!= TM_ATTR_PURE
)
4826 /* If the overridden function is tm_pure, then FNDECL must be. */
4827 else if (found
== TM_ATTR_PURE
&& tm_attr
)
4829 /* Look for base class combinations that cannot be satisfied. */
4830 else if (found
!= TM_ATTR_PURE
&& (found
& TM_ATTR_PURE
))
4832 found
&= ~TM_ATTR_PURE
;
4834 error_at (DECL_SOURCE_LOCATION (fndecl
),
4835 "method overrides both %<transaction_pure%> and %qE methods",
4836 tm_mask_to_attr (found
));
4838 /* If FNDECL did not declare an attribute, then inherit the most
4840 else if (tm_attr
== NULL
)
4842 apply_tm_attr (fndecl
, tm_mask_to_attr (least_bit_hwi (found
)));
4844 /* Otherwise validate that we're not weaker than a function
4845 that is being overridden. */
4849 if (found
<= TM_ATTR_CALLABLE
&& have
> found
)
4855 error_at (DECL_SOURCE_LOCATION (fndecl
),
4856 "method declared %qE overriding %qE method",
4857 tm_attr
, tm_mask_to_attr (found
));
4860 /* For each of the methods in T, propagate a class-level tm attribute. */
4863 set_method_tm_attributes (tree t
)
4865 tree class_tm_attr
, fndecl
;
4867 /* Don't bother collecting tm attributes if transactional memory
4868 support is not enabled. */
4872 /* Process virtual methods first, as they inherit directly from the
4873 base virtual function and also require validation of new attributes. */
4874 if (TYPE_CONTAINS_VPTR_P (t
))
4877 for (vchain
= BINFO_VIRTUALS (TYPE_BINFO (t
)); vchain
;
4878 vchain
= TREE_CHAIN (vchain
))
4880 fndecl
= BV_FN (vchain
);
4881 if (DECL_THUNK_P (fndecl
))
4882 fndecl
= THUNK_TARGET (fndecl
);
4883 set_one_vmethod_tm_attributes (t
, fndecl
);
4887 /* If the class doesn't have an attribute, nothing more to do. */
4888 class_tm_attr
= find_tm_attribute (TYPE_ATTRIBUTES (t
));
4889 if (class_tm_attr
== NULL
)
4892 /* Any method that does not yet have a tm attribute inherits
4893 the one from the class. */
4894 for (fndecl
= TYPE_FIELDS (t
); fndecl
; fndecl
= DECL_CHAIN (fndecl
))
4895 if (DECL_DECLARES_FUNCTION_P (fndecl
)
4896 && !find_tm_attribute (TYPE_ATTRIBUTES (TREE_TYPE (fndecl
))))
4897 apply_tm_attr (fndecl
, class_tm_attr
);
4900 /* Returns true if FN is a default constructor. */
4903 default_ctor_p (tree fn
)
4905 return (DECL_CONSTRUCTOR_P (fn
)
4906 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn
)));
4909 /* Returns true iff class T has a user-defined constructor that can be called
4910 with more than zero arguments. */
4913 type_has_user_nondefault_constructor (tree t
)
4915 if (!TYPE_HAS_USER_CONSTRUCTOR (t
))
4918 for (ovl_iterator
iter (CLASSTYPE_CONSTRUCTORS (t
)); iter
; ++iter
)
4921 if (!DECL_ARTIFICIAL (fn
)
4922 && (TREE_CODE (fn
) == TEMPLATE_DECL
4923 || (skip_artificial_parms_for (fn
, DECL_ARGUMENTS (fn
))
4931 /* Returns the defaulted constructor if T has one. Otherwise, returns
4935 in_class_defaulted_default_constructor (tree t
)
4937 if (!TYPE_HAS_USER_CONSTRUCTOR (t
))
4940 for (ovl_iterator
iter (CLASSTYPE_CONSTRUCTORS (t
)); iter
; ++iter
)
4944 if (DECL_DEFAULTED_IN_CLASS_P (fn
)
4945 && default_ctor_p (fn
))
4952 /* Returns true iff FN is a user-provided function, i.e. user-declared
4953 and not defaulted at its first declaration. */
4956 user_provided_p (tree fn
)
4958 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4961 return (!DECL_ARTIFICIAL (fn
)
4962 && !(DECL_INITIALIZED_IN_CLASS_P (fn
)
4963 && (DECL_DEFAULTED_FN (fn
) || DECL_DELETED_FN (fn
))));
4966 /* Returns true iff class T has a user-provided constructor. */
4969 type_has_user_provided_constructor (tree t
)
4971 if (!CLASS_TYPE_P (t
))
4974 if (!TYPE_HAS_USER_CONSTRUCTOR (t
))
4977 for (ovl_iterator
iter (CLASSTYPE_CONSTRUCTORS (t
)); iter
; ++iter
)
4978 if (user_provided_p (*iter
))
4984 /* Returns true iff class T has a user-provided or explicit constructor. */
4987 type_has_user_provided_or_explicit_constructor (tree t
)
4989 if (!CLASS_TYPE_P (t
))
4992 if (!TYPE_HAS_USER_CONSTRUCTOR (t
))
4995 for (ovl_iterator
iter (CLASSTYPE_CONSTRUCTORS (t
)); iter
; ++iter
)
4998 if (user_provided_p (fn
) || DECL_NONCONVERTING_P (fn
))
5005 /* Returns true iff class T has a non-user-provided (i.e. implicitly
5006 declared or explicitly defaulted in the class body) default
5010 type_has_non_user_provided_default_constructor (tree t
)
5012 if (!TYPE_HAS_DEFAULT_CONSTRUCTOR (t
))
5014 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t
))
5017 for (ovl_iterator
iter (CLASSTYPE_CONSTRUCTORS (t
)); iter
; ++iter
)
5020 if (TREE_CODE (fn
) == FUNCTION_DECL
5021 && default_ctor_p (fn
)
5022 && !user_provided_p (fn
))
5029 /* TYPE is being used as a virtual base, and has a non-trivial move
5030 assignment. Return true if this is due to there being a user-provided
5031 move assignment in TYPE or one of its subobjects; if there isn't, then
5032 multiple move assignment can't cause any harm. */
5035 vbase_has_user_provided_move_assign (tree type
)
5037 /* Does the type itself have a user-provided move assignment operator? */
5038 if (!CLASSTYPE_LAZY_MOVE_ASSIGN (type
))
5039 for (ovl_iterator
iter (get_class_binding_direct
5040 (type
, cp_assignment_operator_id (NOP_EXPR
)));
5042 if (!DECL_ARTIFICIAL (*iter
) && move_fn_p (*iter
))
5045 /* Do any of its bases? */
5046 tree binfo
= TYPE_BINFO (type
);
5048 for (int i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); ++i
)
5049 if (vbase_has_user_provided_move_assign (BINFO_TYPE (base_binfo
)))
5052 /* Or non-static data members? */
5053 for (tree field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
5055 if (TREE_CODE (field
) == FIELD_DECL
5056 && CLASS_TYPE_P (TREE_TYPE (field
))
5057 && vbase_has_user_provided_move_assign (TREE_TYPE (field
)))
5065 /* If default-initialization leaves part of TYPE uninitialized, returns
5066 a DECL for the field or TYPE itself (DR 253). */
5069 default_init_uninitialized_part (tree type
)
5074 type
= strip_array_types (type
);
5075 if (!CLASS_TYPE_P (type
))
5077 if (!type_has_non_user_provided_default_constructor (type
))
5079 for (binfo
= TYPE_BINFO (type
), i
= 0;
5080 BINFO_BASE_ITERATE (binfo
, i
, t
); ++i
)
5082 r
= default_init_uninitialized_part (BINFO_TYPE (t
));
5086 for (t
= TYPE_FIELDS (type
); t
; t
= DECL_CHAIN (t
))
5087 if (TREE_CODE (t
) == FIELD_DECL
5088 && !DECL_ARTIFICIAL (t
)
5089 && !DECL_INITIAL (t
))
5091 r
= default_init_uninitialized_part (TREE_TYPE (t
));
5093 return DECL_P (r
) ? r
: t
;
5099 /* Returns true iff for class T, a trivial synthesized default constructor
5100 would be constexpr. */
5103 trivial_default_constructor_is_constexpr (tree t
)
5105 /* A defaulted trivial default constructor is constexpr
5106 if there is nothing to initialize. */
5107 gcc_assert (!TYPE_HAS_COMPLEX_DFLT (t
));
5108 return is_really_empty_class (t
);
5111 /* Returns true iff class T has a constexpr default constructor. */
5114 type_has_constexpr_default_constructor (tree t
)
5118 if (!CLASS_TYPE_P (t
))
5120 /* The caller should have stripped an enclosing array. */
5121 gcc_assert (TREE_CODE (t
) != ARRAY_TYPE
);
5124 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t
))
5126 if (!TYPE_HAS_COMPLEX_DFLT (t
))
5127 return trivial_default_constructor_is_constexpr (t
);
5128 /* Non-trivial, we need to check subobject constructors. */
5129 lazily_declare_fn (sfk_constructor
, t
);
5131 fns
= locate_ctor (t
);
5132 return (fns
&& DECL_DECLARED_CONSTEXPR_P (fns
));
5135 /* Returns true iff class T has a constexpr default constructor or has an
5136 implicitly declared default constructor that we can't tell if it's constexpr
5137 without forcing a lazy declaration (which might cause undesired
5141 type_maybe_constexpr_default_constructor (tree t
)
5143 if (CLASS_TYPE_P (t
) && CLASSTYPE_LAZY_DEFAULT_CTOR (t
)
5144 && TYPE_HAS_COMPLEX_DFLT (t
))
5145 /* Assume it's constexpr. */
5147 return type_has_constexpr_default_constructor (t
);
5150 /* Returns true iff class TYPE has a virtual destructor. */
5153 type_has_virtual_destructor (tree type
)
5157 if (!CLASS_TYPE_P (type
))
5160 gcc_assert (COMPLETE_TYPE_P (type
));
5161 dtor
= CLASSTYPE_DESTRUCTOR (type
);
5162 return (dtor
&& DECL_VIRTUAL_P (dtor
));
5165 /* Returns true iff T, a class, has a move-assignment or
5166 move-constructor. Does not lazily declare either.
5167 If USER_P is false, any move function will do. If it is true, the
5168 move function must be user-declared.
5170 Note that user-declared here is different from "user-provided",
5171 which doesn't include functions that are defaulted in the
5175 classtype_has_move_assign_or_move_ctor_p (tree t
, bool user_p
)
5178 || (!CLASSTYPE_LAZY_MOVE_CTOR (t
)
5179 && !CLASSTYPE_LAZY_MOVE_ASSIGN (t
)));
5181 if (!CLASSTYPE_LAZY_MOVE_CTOR (t
))
5182 for (ovl_iterator
iter (CLASSTYPE_CONSTRUCTORS (t
)); iter
; ++iter
)
5183 if ((!user_p
|| !DECL_ARTIFICIAL (*iter
)) && move_fn_p (*iter
))
5186 if (!CLASSTYPE_LAZY_MOVE_ASSIGN (t
))
5187 for (ovl_iterator
iter (get_class_binding_direct
5188 (t
, cp_assignment_operator_id (NOP_EXPR
)));
5190 if ((!user_p
|| !DECL_ARTIFICIAL (*iter
)) && move_fn_p (*iter
))
5196 /* Nonzero if we need to build up a constructor call when initializing an
5197 object of this class, either because it has a user-declared constructor
5198 or because it doesn't have a default constructor (so we need to give an
5199 error if no initializer is provided). Use TYPE_NEEDS_CONSTRUCTING when
5200 what you care about is whether or not an object can be produced by a
5201 constructor (e.g. so we don't set TREE_READONLY on const variables of
5202 such type); use this function when what you care about is whether or not
5203 to try to call a constructor to create an object. The latter case is
5204 the former plus some cases of constructors that cannot be called. */
5207 type_build_ctor_call (tree t
)
5210 if (TYPE_NEEDS_CONSTRUCTING (t
))
5212 inner
= strip_array_types (t
);
5213 if (!CLASS_TYPE_P (inner
) || ANON_AGGR_TYPE_P (inner
))
5215 if (!TYPE_HAS_DEFAULT_CONSTRUCTOR (inner
))
5217 if (cxx_dialect
< cxx11
)
5219 /* A user-declared constructor might be private, and a constructor might
5220 be trivial but deleted. */
5221 for (ovl_iterator
iter (get_class_binding (inner
, complete_ctor_identifier
));
5225 if (!DECL_ARTIFICIAL (fn
)
5226 || DECL_DELETED_FN (fn
))
5232 /* Like type_build_ctor_call, but for destructors. */
5235 type_build_dtor_call (tree t
)
5238 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t
))
5240 inner
= strip_array_types (t
);
5241 if (!CLASS_TYPE_P (inner
) || ANON_AGGR_TYPE_P (inner
)
5242 || !COMPLETE_TYPE_P (inner
))
5244 if (cxx_dialect
< cxx11
)
5246 /* A user-declared destructor might be private, and a destructor might
5247 be trivial but deleted. */
5248 for (ovl_iterator
iter (get_class_binding (inner
, complete_dtor_identifier
));
5252 if (!DECL_ARTIFICIAL (fn
)
5253 || DECL_DELETED_FN (fn
))
5259 /* Remove all zero-width bit-fields from T. */
5262 remove_zero_width_bit_fields (tree t
)
5266 fieldsp
= &TYPE_FIELDS (t
);
5269 if (TREE_CODE (*fieldsp
) == FIELD_DECL
5270 && DECL_C_BIT_FIELD (*fieldsp
)
5271 /* We should not be confused by the fact that grokbitfield
5272 temporarily sets the width of the bit field into
5273 DECL_INITIAL (*fieldsp).
5274 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
5276 && (DECL_SIZE (*fieldsp
) == NULL_TREE
5277 || integer_zerop (DECL_SIZE (*fieldsp
))))
5278 *fieldsp
= DECL_CHAIN (*fieldsp
);
5280 fieldsp
= &DECL_CHAIN (*fieldsp
);
5284 /* Returns TRUE iff we need a cookie when dynamically allocating an
5285 array whose elements have the indicated class TYPE. */
5288 type_requires_array_cookie (tree type
)
5291 bool has_two_argument_delete_p
= false;
5293 gcc_assert (CLASS_TYPE_P (type
));
5295 /* If there's a non-trivial destructor, we need a cookie. In order
5296 to iterate through the array calling the destructor for each
5297 element, we'll have to know how many elements there are. */
5298 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
5301 /* If the usual deallocation function is a two-argument whose second
5302 argument is of type `size_t', then we have to pass the size of
5303 the array to the deallocation function, so we will need to store
5305 fns
= lookup_fnfields (TYPE_BINFO (type
),
5306 cp_operator_id (VEC_DELETE_EXPR
),
5308 /* If there are no `operator []' members, or the lookup is
5309 ambiguous, then we don't need a cookie. */
5310 if (!fns
|| fns
== error_mark_node
)
5312 /* Loop through all of the functions. */
5313 for (lkp_iterator
iter (BASELINK_FUNCTIONS (fns
)); iter
; ++iter
)
5317 /* See if this function is a one-argument delete function. If
5318 it is, then it will be the usual deallocation function. */
5319 tree second_parm
= TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn
)));
5320 if (second_parm
== void_list_node
)
5322 /* Do not consider this function if its second argument is an
5326 /* Otherwise, if we have a two-argument function and the second
5327 argument is `size_t', it will be the usual deallocation
5328 function -- unless there is one-argument function, too. */
5329 if (TREE_CHAIN (second_parm
) == void_list_node
5330 && same_type_p (TREE_VALUE (second_parm
), size_type_node
))
5331 has_two_argument_delete_p
= true;
5334 return has_two_argument_delete_p
;
5337 /* Finish computing the `literal type' property of class type T.
5339 At this point, we have already processed base classes and
5340 non-static data members. We need to check whether the copy
5341 constructor is trivial, the destructor is trivial, and there
5342 is a trivial default constructor or at least one constexpr
5343 constructor other than the copy constructor. */
5346 finalize_literal_type_property (tree t
)
5350 if (cxx_dialect
< cxx11
5351 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t
))
5352 CLASSTYPE_LITERAL_P (t
) = false;
5353 else if (CLASSTYPE_LITERAL_P (t
) && LAMBDA_TYPE_P (t
))
5354 CLASSTYPE_LITERAL_P (t
) = (cxx_dialect
>= cxx17
);
5355 else if (CLASSTYPE_LITERAL_P (t
) && !TYPE_HAS_TRIVIAL_DFLT (t
)
5356 && CLASSTYPE_NON_AGGREGATE (t
)
5357 && !TYPE_HAS_CONSTEXPR_CTOR (t
))
5358 CLASSTYPE_LITERAL_P (t
) = false;
5360 /* C++14 DR 1684 removed this restriction. */
5361 if (cxx_dialect
< cxx14
5362 && !CLASSTYPE_LITERAL_P (t
) && !LAMBDA_TYPE_P (t
))
5363 for (fn
= TYPE_FIELDS (t
); fn
; fn
= DECL_CHAIN (fn
))
5364 if (TREE_CODE (fn
) == FUNCTION_DECL
5365 && DECL_DECLARED_CONSTEXPR_P (fn
)
5366 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
)
5367 && !DECL_CONSTRUCTOR_P (fn
))
5369 DECL_DECLARED_CONSTEXPR_P (fn
) = false;
5370 if (!DECL_GENERATED_P (fn
)
5371 && pedwarn (DECL_SOURCE_LOCATION (fn
), OPT_Wpedantic
,
5372 "enclosing class of constexpr non-static member "
5373 "function %q+#D is not a literal type", fn
))
5374 explain_non_literal_class (t
);
5378 /* T is a non-literal type used in a context which requires a constant
5379 expression. Explain why it isn't literal. */
5382 explain_non_literal_class (tree t
)
5384 static hash_set
<tree
> *diagnosed
;
5386 if (!CLASS_TYPE_P (t
))
5388 t
= TYPE_MAIN_VARIANT (t
);
5390 if (diagnosed
== NULL
)
5391 diagnosed
= new hash_set
<tree
>;
5392 if (diagnosed
->add (t
))
5393 /* Already explained. */
5396 inform (0, "%q+T is not literal because:", t
);
5397 if (cxx_dialect
< cxx17
&& LAMBDA_TYPE_P (t
))
5398 inform (0, " %qT is a closure type, which is only literal in "
5399 "C++17 and later", t
);
5400 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t
))
5401 inform (0, " %q+T has a non-trivial destructor", t
);
5402 else if (CLASSTYPE_NON_AGGREGATE (t
)
5403 && !TYPE_HAS_TRIVIAL_DFLT (t
)
5404 && !LAMBDA_TYPE_P (t
)
5405 && !TYPE_HAS_CONSTEXPR_CTOR (t
))
5407 inform (0, " %q+T is not an aggregate, does not have a trivial "
5408 "default constructor, and has no constexpr constructor that "
5409 "is not a copy or move constructor", t
);
5410 if (type_has_non_user_provided_default_constructor (t
))
5411 /* Note that we can't simply call locate_ctor because when the
5412 constructor is deleted it just returns NULL_TREE. */
5413 for (ovl_iterator
iter (CLASSTYPE_CONSTRUCTORS (t
)); iter
; ++iter
)
5416 tree parms
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
5418 parms
= skip_artificial_parms_for (fn
, parms
);
5420 if (sufficient_parms_p (parms
))
5422 if (DECL_DELETED_FN (fn
))
5423 maybe_explain_implicit_delete (fn
);
5425 explain_invalid_constexpr_fn (fn
);
5432 tree binfo
, base_binfo
, field
; int i
;
5433 for (binfo
= TYPE_BINFO (t
), i
= 0;
5434 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
5436 tree basetype
= TREE_TYPE (base_binfo
);
5437 if (!CLASSTYPE_LITERAL_P (basetype
))
5439 inform (0, " base class %qT of %q+T is non-literal",
5441 explain_non_literal_class (basetype
);
5445 for (field
= TYPE_FIELDS (t
); field
; field
= TREE_CHAIN (field
))
5448 if (TREE_CODE (field
) != FIELD_DECL
)
5450 ftype
= TREE_TYPE (field
);
5451 if (!literal_type_p (ftype
))
5453 inform (DECL_SOURCE_LOCATION (field
),
5454 " non-static data member %qD has non-literal type",
5456 if (CLASS_TYPE_P (ftype
))
5457 explain_non_literal_class (ftype
);
5459 if (CP_TYPE_VOLATILE_P (ftype
))
5460 inform (DECL_SOURCE_LOCATION (field
),
5461 " non-static data member %qD has volatile type", field
);
5466 /* Check the validity of the bases and members declared in T. Add any
5467 implicitly-generated functions (like copy-constructors and
5468 assignment operators). Compute various flag bits (like
5469 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
5470 level: i.e., independently of the ABI in use. */
5473 check_bases_and_members (tree t
)
5475 /* Nonzero if the implicitly generated copy constructor should take
5476 a non-const reference argument. */
5477 int cant_have_const_ctor
;
5478 /* Nonzero if the implicitly generated assignment operator
5479 should take a non-const reference argument. */
5480 int no_const_asn_ref
;
5482 bool saved_complex_asn_ref
;
5483 bool saved_nontrivial_dtor
;
5486 /* By default, we use const reference arguments and generate default
5488 cant_have_const_ctor
= 0;
5489 no_const_asn_ref
= 0;
5491 /* Check all the base-classes and set FMEM members to point to arrays
5492 of potential interest. */
5493 check_bases (t
, &cant_have_const_ctor
, &no_const_asn_ref
);
5495 /* Deduce noexcept on destructor. This needs to happen after we've set
5496 triviality flags appropriately for our bases. */
5497 if (cxx_dialect
>= cxx11
)
5498 if (tree dtor
= CLASSTYPE_DESTRUCTOR (t
))
5499 deduce_noexcept_on_destructor (dtor
);
5501 /* Check all the method declarations. */
5504 /* Save the initial values of these flags which only indicate whether
5505 or not the class has user-provided functions. As we analyze the
5506 bases and members we can set these flags for other reasons. */
5507 saved_complex_asn_ref
= TYPE_HAS_COMPLEX_COPY_ASSIGN (t
);
5508 saved_nontrivial_dtor
= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t
);
5510 /* Check all the data member declarations. We cannot call
5511 check_field_decls until we have called check_bases check_methods,
5512 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
5513 being set appropriately. */
5514 check_field_decls (t
, &access_decls
,
5515 &cant_have_const_ctor
,
5518 /* A nearly-empty class has to be vptr-containing; a nearly empty
5519 class contains just a vptr. */
5520 if (!TYPE_CONTAINS_VPTR_P (t
))
5521 CLASSTYPE_NEARLY_EMPTY_P (t
) = 0;
5523 /* Do some bookkeeping that will guide the generation of implicitly
5524 declared member functions. */
5525 TYPE_HAS_COMPLEX_COPY_CTOR (t
) |= TYPE_CONTAINS_VPTR_P (t
);
5526 TYPE_HAS_COMPLEX_MOVE_CTOR (t
) |= TYPE_CONTAINS_VPTR_P (t
);
5527 /* We need to call a constructor for this class if it has a
5528 user-provided constructor, or if the default constructor is going
5529 to initialize the vptr. (This is not an if-and-only-if;
5530 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
5531 themselves need constructing.) */
5532 TYPE_NEEDS_CONSTRUCTING (t
)
5533 |= (type_has_user_provided_constructor (t
) || TYPE_CONTAINS_VPTR_P (t
));
5536 An aggregate is an array or a class with no user-provided
5537 constructors ... and no virtual functions.
5539 Again, other conditions for being an aggregate are checked
5541 CLASSTYPE_NON_AGGREGATE (t
)
5542 |= (type_has_user_provided_or_explicit_constructor (t
)
5543 || TYPE_POLYMORPHIC_P (t
));
5544 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
5545 retain the old definition internally for ABI reasons. */
5546 CLASSTYPE_NON_LAYOUT_POD_P (t
)
5547 |= (CLASSTYPE_NON_AGGREGATE (t
)
5548 || saved_nontrivial_dtor
|| saved_complex_asn_ref
);
5549 CLASSTYPE_NON_STD_LAYOUT (t
) |= TYPE_CONTAINS_VPTR_P (t
);
5550 TYPE_HAS_COMPLEX_COPY_ASSIGN (t
) |= TYPE_CONTAINS_VPTR_P (t
);
5551 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t
) |= TYPE_CONTAINS_VPTR_P (t
);
5552 TYPE_HAS_COMPLEX_DFLT (t
) |= TYPE_CONTAINS_VPTR_P (t
);
5554 /* If the only explicitly declared default constructor is user-provided,
5555 set TYPE_HAS_COMPLEX_DFLT. */
5556 if (!TYPE_HAS_COMPLEX_DFLT (t
)
5557 && TYPE_HAS_DEFAULT_CONSTRUCTOR (t
)
5558 && !type_has_non_user_provided_default_constructor (t
))
5559 TYPE_HAS_COMPLEX_DFLT (t
) = true;
5561 /* Warn if a public base of a polymorphic type has an accessible
5562 non-virtual destructor. It is only now that we know the class is
5563 polymorphic. Although a polymorphic base will have a already
5564 been diagnosed during its definition, we warn on use too. */
5565 if (TYPE_POLYMORPHIC_P (t
) && warn_nonvdtor
)
5567 tree binfo
= TYPE_BINFO (t
);
5568 vec
<tree
, va_gc
> *accesses
= BINFO_BASE_ACCESSES (binfo
);
5572 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
5574 tree basetype
= TREE_TYPE (base_binfo
);
5576 if ((*accesses
)[i
] == access_public_node
5577 && (TYPE_POLYMORPHIC_P (basetype
) || warn_ecpp
)
5578 && accessible_nvdtor_p (basetype
))
5579 warning (OPT_Wnon_virtual_dtor
,
5580 "base class %q#T has accessible non-virtual destructor",
5585 /* If the class has no user-declared constructor, but does have
5586 non-static const or reference data members that can never be
5587 initialized, issue a warning. */
5588 if (warn_uninitialized
5589 /* Classes with user-declared constructors are presumed to
5590 initialize these members. */
5591 && !TYPE_HAS_USER_CONSTRUCTOR (t
)
5592 /* Aggregates can be initialized with brace-enclosed
5594 && CLASSTYPE_NON_AGGREGATE (t
))
5598 for (field
= TYPE_FIELDS (t
); field
; field
= DECL_CHAIN (field
))
5602 if (TREE_CODE (field
) != FIELD_DECL
5603 || DECL_INITIAL (field
) != NULL_TREE
)
5606 type
= TREE_TYPE (field
);
5607 if (TREE_CODE (type
) == REFERENCE_TYPE
)
5608 warning_at (DECL_SOURCE_LOCATION (field
),
5609 OPT_Wuninitialized
, "non-static reference %q#D "
5610 "in class without a constructor", field
);
5611 else if (CP_TYPE_CONST_P (type
)
5612 && (!CLASS_TYPE_P (type
)
5613 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type
)))
5614 warning_at (DECL_SOURCE_LOCATION (field
),
5615 OPT_Wuninitialized
, "non-static const member %q#D "
5616 "in class without a constructor", field
);
5620 /* Synthesize any needed methods. */
5621 add_implicitly_declared_members (t
, &access_decls
,
5622 cant_have_const_ctor
,
5625 /* Check defaulted declarations here so we have cant_have_const_ctor
5626 and don't need to worry about clones. */
5627 for (fn
= TYPE_FIELDS (t
); fn
; fn
= DECL_CHAIN (fn
))
5628 if (DECL_DECLARES_FUNCTION_P (fn
)
5629 && !DECL_ARTIFICIAL (fn
)
5630 && DECL_DEFAULTED_IN_CLASS_P (fn
))
5632 int copy
= copy_fn_p (fn
);
5636 = (DECL_CONSTRUCTOR_P (fn
) ? !cant_have_const_ctor
5637 : !no_const_asn_ref
);
5638 bool fn_const_p
= (copy
== 2);
5640 if (fn_const_p
&& !imp_const_p
)
5641 /* If the function is defaulted outside the class, we just
5642 give the synthesis error. */
5643 error ("%q+D declared to take const reference, but implicit "
5644 "declaration would take non-const", fn
);
5646 defaulted_late_check (fn
);
5649 if (LAMBDA_TYPE_P (t
))
5651 /* "This class type is not an aggregate." */
5652 CLASSTYPE_NON_AGGREGATE (t
) = 1;
5655 /* Compute the 'literal type' property before we
5656 do anything with non-static member functions. */
5657 finalize_literal_type_property (t
);
5659 /* Create the in-charge and not-in-charge variants of constructors
5661 clone_constructors_and_destructors (t
);
5663 /* Process the using-declarations. */
5664 for (; access_decls
; access_decls
= TREE_CHAIN (access_decls
))
5665 handle_using_decl (TREE_VALUE (access_decls
), t
);
5667 /* Figure out whether or not we will need a cookie when dynamically
5668 allocating an array of this type. */
5669 LANG_TYPE_CLASS_CHECK (t
)->vec_new_uses_cookie
5670 = type_requires_array_cookie (t
);
5673 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
5674 accordingly. If a new vfield was created (because T doesn't have a
5675 primary base class), then the newly created field is returned. It
5676 is not added to the TYPE_FIELDS list; it is the caller's
5677 responsibility to do that. Accumulate declared virtual functions
5681 create_vtable_ptr (tree t
, tree
* virtuals_p
)
5685 /* Collect the virtual functions declared in T. */
5686 for (fn
= TYPE_FIELDS (t
); fn
; fn
= DECL_CHAIN (fn
))
5687 if (TREE_CODE (fn
) == FUNCTION_DECL
5688 && DECL_VINDEX (fn
) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn
)
5689 && TREE_CODE (DECL_VINDEX (fn
)) != INTEGER_CST
)
5691 tree new_virtual
= make_node (TREE_LIST
);
5693 BV_FN (new_virtual
) = fn
;
5694 BV_DELTA (new_virtual
) = integer_zero_node
;
5695 BV_VCALL_INDEX (new_virtual
) = NULL_TREE
;
5697 TREE_CHAIN (new_virtual
) = *virtuals_p
;
5698 *virtuals_p
= new_virtual
;
5701 /* If we couldn't find an appropriate base class, create a new field
5702 here. Even if there weren't any new virtual functions, we might need a
5703 new virtual function table if we're supposed to include vptrs in
5704 all classes that need them. */
5705 if (!TYPE_VFIELD (t
) && (*virtuals_p
|| TYPE_CONTAINS_VPTR_P (t
)))
5707 /* We build this decl with vtbl_ptr_type_node, which is a
5708 `vtable_entry_type*'. It might seem more precise to use
5709 `vtable_entry_type (*)[N]' where N is the number of virtual
5710 functions. However, that would require the vtable pointer in
5711 base classes to have a different type than the vtable pointer
5712 in derived classes. We could make that happen, but that
5713 still wouldn't solve all the problems. In particular, the
5714 type-based alias analysis code would decide that assignments
5715 to the base class vtable pointer can't alias assignments to
5716 the derived class vtable pointer, since they have different
5717 types. Thus, in a derived class destructor, where the base
5718 class constructor was inlined, we could generate bad code for
5719 setting up the vtable pointer.
5721 Therefore, we use one type for all vtable pointers. We still
5722 use a type-correct type; it's just doesn't indicate the array
5723 bounds. That's better than using `void*' or some such; it's
5724 cleaner, and it let's the alias analysis code know that these
5725 stores cannot alias stores to void*! */
5728 field
= build_decl (input_location
,
5729 FIELD_DECL
, get_vfield_name (t
), vtbl_ptr_type_node
);
5730 DECL_VIRTUAL_P (field
) = 1;
5731 DECL_ARTIFICIAL (field
) = 1;
5732 DECL_FIELD_CONTEXT (field
) = t
;
5733 DECL_FCONTEXT (field
) = t
;
5734 if (TYPE_PACKED (t
))
5735 DECL_PACKED (field
) = 1;
5737 TYPE_VFIELD (t
) = field
;
5739 /* This class is non-empty. */
5740 CLASSTYPE_EMPTY_P (t
) = 0;
5748 /* Add OFFSET to all base types of BINFO which is a base in the
5749 hierarchy dominated by T.
5751 OFFSET, which is a type offset, is number of bytes. */
5754 propagate_binfo_offsets (tree binfo
, tree offset
)
5760 /* Update BINFO's offset. */
5761 BINFO_OFFSET (binfo
)
5762 = fold_convert (sizetype
,
5763 size_binop (PLUS_EXPR
,
5764 fold_convert (ssizetype
, BINFO_OFFSET (binfo
)),
5767 /* Find the primary base class. */
5768 primary_binfo
= get_primary_binfo (binfo
);
5770 if (primary_binfo
&& BINFO_INHERITANCE_CHAIN (primary_binfo
) == binfo
)
5771 propagate_binfo_offsets (primary_binfo
, offset
);
5773 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
5775 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); ++i
)
5777 /* Don't do the primary base twice. */
5778 if (base_binfo
== primary_binfo
)
5781 if (BINFO_VIRTUAL_P (base_binfo
))
5784 propagate_binfo_offsets (base_binfo
, offset
);
5788 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
5789 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
5790 empty subobjects of T. */
5793 layout_virtual_bases (record_layout_info rli
, splay_tree offsets
)
5799 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t
)) == 0)
5802 /* Find the last field. The artificial fields created for virtual
5803 bases will go after the last extant field to date. */
5804 next_field
= &TYPE_FIELDS (t
);
5806 next_field
= &DECL_CHAIN (*next_field
);
5808 /* Go through the virtual bases, allocating space for each virtual
5809 base that is not already a primary base class. These are
5810 allocated in inheritance graph order. */
5811 for (vbase
= TYPE_BINFO (t
); vbase
; vbase
= TREE_CHAIN (vbase
))
5813 if (!BINFO_VIRTUAL_P (vbase
))
5816 if (!BINFO_PRIMARY_P (vbase
))
5818 /* This virtual base is not a primary base of any class in the
5819 hierarchy, so we have to add space for it. */
5820 next_field
= build_base_field (rli
, vbase
,
5821 offsets
, next_field
);
5826 /* Returns the offset of the byte just past the end of the base class
5830 end_of_base (tree binfo
)
5834 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo
)))
5835 size
= TYPE_SIZE_UNIT (char_type_node
);
5836 else if (is_empty_class (BINFO_TYPE (binfo
)))
5837 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
5838 allocate some space for it. It cannot have virtual bases, so
5839 TYPE_SIZE_UNIT is fine. */
5840 size
= TYPE_SIZE_UNIT (BINFO_TYPE (binfo
));
5842 size
= CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo
));
5844 return size_binop (PLUS_EXPR
, BINFO_OFFSET (binfo
), size
);
5847 /* Returns the offset of the byte just past the end of the base class
5848 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
5849 only non-virtual bases are included. */
5852 end_of_class (tree t
, int include_virtuals_p
)
5854 tree result
= size_zero_node
;
5855 vec
<tree
, va_gc
> *vbases
;
5861 for (binfo
= TYPE_BINFO (t
), i
= 0;
5862 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); ++i
)
5864 if (!include_virtuals_p
5865 && BINFO_VIRTUAL_P (base_binfo
)
5866 && (!BINFO_PRIMARY_P (base_binfo
)
5867 || BINFO_INHERITANCE_CHAIN (base_binfo
) != TYPE_BINFO (t
)))
5870 offset
= end_of_base (base_binfo
);
5871 if (tree_int_cst_lt (result
, offset
))
5875 if (include_virtuals_p
)
5876 for (vbases
= CLASSTYPE_VBASECLASSES (t
), i
= 0;
5877 vec_safe_iterate (vbases
, i
, &base_binfo
); i
++)
5879 offset
= end_of_base (base_binfo
);
5880 if (tree_int_cst_lt (result
, offset
))
5887 /* Warn about bases of T that are inaccessible because they are
5888 ambiguous. For example:
5891 struct T : public S {};
5892 struct U : public S, public T {};
5894 Here, `(S*) new U' is not allowed because there are two `S'
5898 warn_about_ambiguous_bases (tree t
)
5901 vec
<tree
, va_gc
> *vbases
;
5906 /* If there are no repeated bases, nothing can be ambiguous. */
5907 if (!CLASSTYPE_REPEATED_BASE_P (t
))
5910 /* Check direct bases. */
5911 for (binfo
= TYPE_BINFO (t
), i
= 0;
5912 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); ++i
)
5914 basetype
= BINFO_TYPE (base_binfo
);
5916 if (!uniquely_derived_from_p (basetype
, t
))
5917 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
5921 /* Check for ambiguous virtual bases. */
5923 for (vbases
= CLASSTYPE_VBASECLASSES (t
), i
= 0;
5924 vec_safe_iterate (vbases
, i
, &binfo
); i
++)
5926 basetype
= BINFO_TYPE (binfo
);
5928 if (!uniquely_derived_from_p (basetype
, t
))
5929 warning (OPT_Wextra
, "virtual base %qT inaccessible in %qT due "
5930 "to ambiguity", basetype
, t
);
5934 /* Compare two INTEGER_CSTs K1 and K2. */
5937 splay_tree_compare_integer_csts (splay_tree_key k1
, splay_tree_key k2
)
5939 return tree_int_cst_compare ((tree
) k1
, (tree
) k2
);
5942 /* Increase the size indicated in RLI to account for empty classes
5943 that are "off the end" of the class. */
5946 include_empty_classes (record_layout_info rli
)
5951 /* It might be the case that we grew the class to allocate a
5952 zero-sized base class. That won't be reflected in RLI, yet,
5953 because we are willing to overlay multiple bases at the same
5954 offset. However, now we need to make sure that RLI is big enough
5955 to reflect the entire class. */
5956 eoc
= end_of_class (rli
->t
, CLASSTYPE_AS_BASE (rli
->t
) != NULL_TREE
);
5957 rli_size
= rli_size_unit_so_far (rli
);
5958 if (TREE_CODE (rli_size
) == INTEGER_CST
5959 && tree_int_cst_lt (rli_size
, eoc
))
5961 /* The size should have been rounded to a whole byte. */
5962 gcc_assert (tree_int_cst_equal
5963 (rli
->bitpos
, round_down (rli
->bitpos
, BITS_PER_UNIT
)));
5965 = size_binop (PLUS_EXPR
,
5967 size_binop (MULT_EXPR
,
5968 fold_convert (bitsizetype
,
5969 size_binop (MINUS_EXPR
,
5971 bitsize_int (BITS_PER_UNIT
)));
5972 normalize_rli (rli
);
5976 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
5977 BINFO_OFFSETs for all of the base-classes. Position the vtable
5978 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
5981 layout_class_type (tree t
, tree
*virtuals_p
)
5983 tree non_static_data_members
;
5986 record_layout_info rli
;
5987 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
5988 types that appear at that offset. */
5989 splay_tree empty_base_offsets
;
5990 /* True if the last field laid out was a bit-field. */
5991 bool last_field_was_bitfield
= false;
5992 /* The location at which the next field should be inserted. */
5994 /* T, as a base class. */
5997 /* Keep track of the first non-static data member. */
5998 non_static_data_members
= TYPE_FIELDS (t
);
6000 /* Start laying out the record. */
6001 rli
= start_record_layout (t
);
6003 /* Mark all the primary bases in the hierarchy. */
6004 determine_primary_bases (t
);
6006 /* Create a pointer to our virtual function table. */
6007 vptr
= create_vtable_ptr (t
, virtuals_p
);
6009 /* The vptr is always the first thing in the class. */
6012 DECL_CHAIN (vptr
) = TYPE_FIELDS (t
);
6013 TYPE_FIELDS (t
) = vptr
;
6014 next_field
= &DECL_CHAIN (vptr
);
6015 place_field (rli
, vptr
);
6018 next_field
= &TYPE_FIELDS (t
);
6020 /* Build FIELD_DECLs for all of the non-virtual base-types. */
6021 empty_base_offsets
= splay_tree_new (splay_tree_compare_integer_csts
,
6023 build_base_fields (rli
, empty_base_offsets
, next_field
);
6025 /* Layout the non-static data members. */
6026 for (field
= non_static_data_members
; field
; field
= DECL_CHAIN (field
))
6031 /* We still pass things that aren't non-static data members to
6032 the back end, in case it wants to do something with them. */
6033 if (TREE_CODE (field
) != FIELD_DECL
)
6035 place_field (rli
, field
);
6036 /* If the static data member has incomplete type, keep track
6037 of it so that it can be completed later. (The handling
6038 of pending statics in finish_record_layout is
6039 insufficient; consider:
6042 struct S2 { static S1 s1; };
6044 At this point, finish_record_layout will be called, but
6045 S1 is still incomplete.) */
6048 maybe_register_incomplete_var (field
);
6049 /* The visibility of static data members is determined
6050 at their point of declaration, not their point of
6052 determine_visibility (field
);
6057 type
= TREE_TYPE (field
);
6058 if (type
== error_mark_node
)
6061 padding
= NULL_TREE
;
6063 /* If this field is a bit-field whose width is greater than its
6064 type, then there are some special rules for allocating
6066 if (DECL_C_BIT_FIELD (field
)
6067 && tree_int_cst_lt (TYPE_SIZE (type
), DECL_SIZE (field
)))
6069 bool was_unnamed_p
= false;
6070 /* We must allocate the bits as if suitably aligned for the
6071 longest integer type that fits in this many bits. Then,
6072 we are supposed to use the left over bits as additional
6075 /* Do not pick a type bigger than MAX_FIXED_MODE_SIZE. */
6076 tree limit
= size_int (MAX_FIXED_MODE_SIZE
);
6077 if (tree_int_cst_lt (DECL_SIZE (field
), limit
))
6078 limit
= DECL_SIZE (field
);
6080 tree integer_type
= integer_types
[itk_char
];
6081 for (unsigned itk
= itk_char
; itk
!= itk_none
; itk
++)
6082 if (tree next
= integer_types
[itk
])
6084 if (tree_int_cst_lt (limit
, TYPE_SIZE (next
)))
6085 /* Too big, so our current guess is what we want. */
6087 /* Not bigger than limit, ok */
6088 integer_type
= next
;
6091 /* Figure out how much additional padding is required. */
6092 if (TREE_CODE (t
) == UNION_TYPE
)
6093 /* In a union, the padding field must have the full width
6094 of the bit-field; all fields start at offset zero. */
6095 padding
= DECL_SIZE (field
);
6097 padding
= size_binop (MINUS_EXPR
, DECL_SIZE (field
),
6098 TYPE_SIZE (integer_type
));
6100 if (integer_zerop (padding
))
6101 padding
= NULL_TREE
;
6103 /* An unnamed bitfield does not normally affect the
6104 alignment of the containing class on a target where
6105 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
6106 make any exceptions for unnamed bitfields when the
6107 bitfields are longer than their types. Therefore, we
6108 temporarily give the field a name. */
6109 if (PCC_BITFIELD_TYPE_MATTERS
&& !DECL_NAME (field
))
6111 was_unnamed_p
= true;
6112 DECL_NAME (field
) = make_anon_name ();
6115 DECL_SIZE (field
) = TYPE_SIZE (integer_type
);
6116 SET_DECL_ALIGN (field
, TYPE_ALIGN (integer_type
));
6117 DECL_USER_ALIGN (field
) = TYPE_USER_ALIGN (integer_type
);
6118 layout_nonempty_base_or_field (rli
, field
, NULL_TREE
,
6119 empty_base_offsets
);
6121 DECL_NAME (field
) = NULL_TREE
;
6122 /* Now that layout has been performed, set the size of the
6123 field to the size of its declared type; the rest of the
6124 field is effectively invisible. */
6125 DECL_SIZE (field
) = TYPE_SIZE (type
);
6126 /* We must also reset the DECL_MODE of the field. */
6127 SET_DECL_MODE (field
, TYPE_MODE (type
));
6130 layout_nonempty_base_or_field (rli
, field
, NULL_TREE
,
6131 empty_base_offsets
);
6133 /* Remember the location of any empty classes in FIELD. */
6134 record_subobject_offsets (TREE_TYPE (field
),
6135 byte_position(field
),
6137 /*is_data_member=*/true);
6139 /* If a bit-field does not immediately follow another bit-field,
6140 and yet it starts in the middle of a byte, we have failed to
6141 comply with the ABI. */
6143 && DECL_C_BIT_FIELD (field
)
6144 /* The TREE_NO_WARNING flag gets set by Objective-C when
6145 laying out an Objective-C class. The ObjC ABI differs
6146 from the C++ ABI, and so we do not want a warning
6148 && !TREE_NO_WARNING (field
)
6149 && !last_field_was_bitfield
6150 && !integer_zerop (size_binop (TRUNC_MOD_EXPR
,
6151 DECL_FIELD_BIT_OFFSET (field
),
6152 bitsize_unit_node
)))
6153 warning_at (DECL_SOURCE_LOCATION (field
), OPT_Wabi
,
6154 "offset of %qD is not ABI-compliant and may "
6155 "change in a future version of GCC", field
);
6157 /* The middle end uses the type of expressions to determine the
6158 possible range of expression values. In order to optimize
6159 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
6160 must be made aware of the width of "i", via its type.
6162 Because C++ does not have integer types of arbitrary width,
6163 we must (for the purposes of the front end) convert from the
6164 type assigned here to the declared type of the bitfield
6165 whenever a bitfield expression is used as an rvalue.
6166 Similarly, when assigning a value to a bitfield, the value
6167 must be converted to the type given the bitfield here. */
6168 if (DECL_C_BIT_FIELD (field
))
6170 unsigned HOST_WIDE_INT width
;
6171 tree ftype
= TREE_TYPE (field
);
6172 width
= tree_to_uhwi (DECL_SIZE (field
));
6173 if (width
!= TYPE_PRECISION (ftype
))
6176 = c_build_bitfield_integer_type (width
,
6177 TYPE_UNSIGNED (ftype
));
6179 = cp_build_qualified_type (TREE_TYPE (field
),
6180 cp_type_quals (ftype
));
6184 /* If we needed additional padding after this field, add it
6190 padding_field
= build_decl (input_location
,
6194 DECL_BIT_FIELD (padding_field
) = 1;
6195 DECL_SIZE (padding_field
) = padding
;
6196 DECL_CONTEXT (padding_field
) = t
;
6197 DECL_ARTIFICIAL (padding_field
) = 1;
6198 DECL_IGNORED_P (padding_field
) = 1;
6199 layout_nonempty_base_or_field (rli
, padding_field
,
6201 empty_base_offsets
);
6204 last_field_was_bitfield
= DECL_C_BIT_FIELD (field
);
6207 if (!integer_zerop (rli
->bitpos
))
6209 /* Make sure that we are on a byte boundary so that the size of
6210 the class without virtual bases will always be a round number
6212 rli
->bitpos
= round_up_loc (input_location
, rli
->bitpos
, BITS_PER_UNIT
);
6213 normalize_rli (rli
);
6216 /* Delete all zero-width bit-fields from the list of fields. Now
6217 that the type is laid out they are no longer important. */
6218 remove_zero_width_bit_fields (t
);
6220 /* Create the version of T used for virtual bases. We do not use
6221 make_class_type for this version; this is an artificial type. For
6222 a POD type, we just reuse T. */
6223 if (CLASSTYPE_NON_LAYOUT_POD_P (t
) || CLASSTYPE_EMPTY_P (t
))
6225 base_t
= make_node (TREE_CODE (t
));
6227 /* Set the size and alignment for the new type. */
6230 /* If the ABI version is not at least two, and the last
6231 field was a bit-field, RLI may not be on a byte
6232 boundary. In particular, rli_size_unit_so_far might
6233 indicate the last complete byte, while rli_size_so_far
6234 indicates the total number of bits used. Therefore,
6235 rli_size_so_far, rather than rli_size_unit_so_far, is
6236 used to compute TYPE_SIZE_UNIT. */
6237 eoc
= end_of_class (t
, /*include_virtuals_p=*/0);
6238 TYPE_SIZE_UNIT (base_t
)
6239 = size_binop (MAX_EXPR
,
6240 fold_convert (sizetype
,
6241 size_binop (CEIL_DIV_EXPR
,
6242 rli_size_so_far (rli
),
6243 bitsize_int (BITS_PER_UNIT
))),
6246 = size_binop (MAX_EXPR
,
6247 rli_size_so_far (rli
),
6248 size_binop (MULT_EXPR
,
6249 fold_convert (bitsizetype
, eoc
),
6250 bitsize_int (BITS_PER_UNIT
)));
6251 SET_TYPE_ALIGN (base_t
, rli
->record_align
);
6252 TYPE_USER_ALIGN (base_t
) = TYPE_USER_ALIGN (t
);
6254 /* Copy the fields from T. */
6255 next_field
= &TYPE_FIELDS (base_t
);
6256 for (field
= TYPE_FIELDS (t
); field
; field
= DECL_CHAIN (field
))
6257 if (TREE_CODE (field
) == FIELD_DECL
)
6259 *next_field
= copy_node (field
);
6260 DECL_CONTEXT (*next_field
) = base_t
;
6261 next_field
= &DECL_CHAIN (*next_field
);
6263 *next_field
= NULL_TREE
;
6265 /* Record the base version of the type. */
6266 CLASSTYPE_AS_BASE (t
) = base_t
;
6267 TYPE_CONTEXT (base_t
) = t
;
6270 CLASSTYPE_AS_BASE (t
) = t
;
6272 /* Every empty class contains an empty class. */
6273 if (CLASSTYPE_EMPTY_P (t
))
6274 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t
) = 1;
6276 /* Set the TYPE_DECL for this type to contain the right
6277 value for DECL_OFFSET, so that we can use it as part
6278 of a COMPONENT_REF for multiple inheritance. */
6279 layout_decl (TYPE_MAIN_DECL (t
), 0);
6281 /* Now fix up any virtual base class types that we left lying
6282 around. We must get these done before we try to lay out the
6283 virtual function table. As a side-effect, this will remove the
6284 base subobject fields. */
6285 layout_virtual_bases (rli
, empty_base_offsets
);
6287 /* Make sure that empty classes are reflected in RLI at this
6289 include_empty_classes (rli
);
6291 /* Make sure not to create any structures with zero size. */
6292 if (integer_zerop (rli_size_unit_so_far (rli
)) && CLASSTYPE_EMPTY_P (t
))
6294 build_decl (input_location
,
6295 FIELD_DECL
, NULL_TREE
, char_type_node
));
6297 /* If this is a non-POD, declaring it packed makes a difference to how it
6298 can be used as a field; don't let finalize_record_size undo it. */
6299 if (TYPE_PACKED (t
) && !layout_pod_type_p (t
))
6300 rli
->packed_maybe_necessary
= true;
6302 /* Let the back end lay out the type. */
6303 finish_record_layout (rli
, /*free_p=*/true);
6305 if (TYPE_SIZE_UNIT (t
)
6306 && TREE_CODE (TYPE_SIZE_UNIT (t
)) == INTEGER_CST
6307 && !TREE_OVERFLOW (TYPE_SIZE_UNIT (t
))
6308 && !valid_constant_size_p (TYPE_SIZE_UNIT (t
)))
6309 error ("size of type %qT is too large (%qE bytes)", t
, TYPE_SIZE_UNIT (t
));
6311 /* Warn about bases that can't be talked about due to ambiguity. */
6312 warn_about_ambiguous_bases (t
);
6314 /* Now that we're done with layout, give the base fields the real types. */
6315 for (field
= TYPE_FIELDS (t
); field
; field
= DECL_CHAIN (field
))
6316 if (DECL_ARTIFICIAL (field
) && IS_FAKE_BASE_TYPE (TREE_TYPE (field
)))
6317 TREE_TYPE (field
) = TYPE_CONTEXT (TREE_TYPE (field
));
6320 splay_tree_delete (empty_base_offsets
);
6322 if (CLASSTYPE_EMPTY_P (t
)
6323 && tree_int_cst_lt (sizeof_biggest_empty_class
,
6324 TYPE_SIZE_UNIT (t
)))
6325 sizeof_biggest_empty_class
= TYPE_SIZE_UNIT (t
);
6328 /* Determine the "key method" for the class type indicated by TYPE,
6329 and set CLASSTYPE_KEY_METHOD accordingly. */
6332 determine_key_method (tree type
)
6336 if (processing_template_decl
6337 || CLASSTYPE_TEMPLATE_INSTANTIATION (type
)
6338 || CLASSTYPE_INTERFACE_KNOWN (type
))
6341 /* The key method is the first non-pure virtual function that is not
6342 inline at the point of class definition. On some targets the
6343 key function may not be inline; those targets should not call
6344 this function until the end of the translation unit. */
6345 for (method
= TYPE_FIELDS (type
); method
; method
= DECL_CHAIN (method
))
6346 if (TREE_CODE (method
) == FUNCTION_DECL
6347 && DECL_VINDEX (method
) != NULL_TREE
6348 && ! DECL_DECLARED_INLINE_P (method
)
6349 && ! DECL_PURE_VIRTUAL_P (method
))
6351 CLASSTYPE_KEY_METHOD (type
) = method
;
6358 /* Helper of find_flexarrays. Return true when FLD refers to a non-static
6359 class data member of non-zero size, otherwise false. */
6362 field_nonempty_p (const_tree fld
)
6364 if (TREE_CODE (fld
) == ERROR_MARK
)
6367 tree type
= TREE_TYPE (fld
);
6368 if (TREE_CODE (fld
) == FIELD_DECL
6369 && TREE_CODE (type
) != ERROR_MARK
6370 && (DECL_NAME (fld
) || RECORD_OR_UNION_TYPE_P (type
)))
6372 return TYPE_SIZE (type
)
6373 && (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
6374 || !tree_int_cst_equal (size_zero_node
, TYPE_SIZE (type
)));
6380 /* Used by find_flexarrays and related functions. */
6384 /* The first flexible array member or non-zero array member found
6385 in the order of layout. */
6387 /* First non-static non-empty data member in the class or its bases. */
6389 /* The first non-static non-empty data member following either
6390 the flexible array member, if found, or the zero-length array member
6391 otherwise. AFTER[1] refers to the first such data member of a union
6392 of which the struct containing the flexible array member or zero-length
6393 array is a member, or NULL when no such union exists. This element is
6394 only used during searching, not for diagnosing problems. AFTER[0]
6395 refers to the first such data member that is not a member of such
6399 /* Refers to a struct (not union) in which the struct of which the flexible
6400 array is member is defined. Used to diagnose strictly (according to C)
6401 invalid uses of the latter structs. */
6405 /* Find either the first flexible array member or the first zero-length
6406 array, in that order of preference, among members of class T (but not
6407 its base classes), and set members of FMEM accordingly.
6408 BASE_P is true if T is a base class of another class.
6409 PUN is set to the outermost union in which the flexible array member
6410 (or zero-length array) is defined if one such union exists, otherwise
6412 Similarly, PSTR is set to a data member of the outermost struct of
6413 which the flexible array is a member if one such struct exists,
6414 otherwise to NULL. */
6417 find_flexarrays (tree t
, flexmems_t
*fmem
, bool base_p
,
6418 tree pun
/* = NULL_TREE */,
6419 tree pstr
/* = NULL_TREE */)
6421 /* Set the "pointer" to the outermost enclosing union if not set
6422 yet and maintain it for the remainder of the recursion. */
6423 if (!pun
&& TREE_CODE (t
) == UNION_TYPE
)
6426 for (tree fld
= TYPE_FIELDS (t
); fld
; fld
= DECL_CHAIN (fld
))
6428 if (fld
== error_mark_node
)
6431 /* Is FLD a typedef for an anonymous struct? */
6433 /* FIXME: Note that typedefs (as well as arrays) need to be fully
6434 handled elsewhere so that errors like the following are detected
6436 typedef struct { int i, a[], j; } S; // bug c++/72753
6437 S s [2]; // bug c++/68489
6439 if (TREE_CODE (fld
) == TYPE_DECL
6440 && DECL_IMPLICIT_TYPEDEF_P (fld
)
6441 && CLASS_TYPE_P (TREE_TYPE (fld
))
6442 && anon_aggrname_p (DECL_NAME (fld
)))
6444 /* Check the nested unnamed type referenced via a typedef
6445 independently of FMEM (since it's not a data member of
6446 the enclosing class). */
6447 check_flexarrays (TREE_TYPE (fld
));
6451 /* Skip anything that's GCC-generated or not a (non-static) data
6453 if (DECL_ARTIFICIAL (fld
) || TREE_CODE (fld
) != FIELD_DECL
)
6456 /* Type of the member. */
6457 tree fldtype
= TREE_TYPE (fld
);
6458 if (fldtype
== error_mark_node
)
6461 /* Determine the type of the array element or object referenced
6462 by the member so that it can be checked for flexible array
6463 members if it hasn't been yet. */
6464 tree eltype
= fldtype
;
6465 while (TREE_CODE (eltype
) == ARRAY_TYPE
6466 || TREE_CODE (eltype
) == POINTER_TYPE
6467 || TREE_CODE (eltype
) == REFERENCE_TYPE
)
6468 eltype
= TREE_TYPE (eltype
);
6470 if (RECORD_OR_UNION_TYPE_P (eltype
))
6472 if (fmem
->array
&& !fmem
->after
[bool (pun
)])
6474 /* Once the member after the flexible array has been found
6476 fmem
->after
[bool (pun
)] = fld
;
6480 if (eltype
== fldtype
|| TYPE_UNNAMED_P (eltype
))
6482 /* Descend into the non-static member struct or union and try
6483 to find a flexible array member or zero-length array among
6484 its members. This is only necessary for anonymous types
6485 and types in whose context the current type T has not been
6486 defined (the latter must not be checked again because they
6487 are already in the process of being checked by one of the
6488 recursive calls). */
6490 tree first
= fmem
->first
;
6491 tree array
= fmem
->array
;
6493 /* If this member isn't anonymous and a prior non-flexible array
6494 member has been seen in one of the enclosing structs, clear
6495 the FIRST member since it doesn't contribute to the flexible
6496 array struct's members. */
6497 if (first
&& !array
&& !ANON_AGGR_TYPE_P (eltype
))
6498 fmem
->first
= NULL_TREE
;
6500 find_flexarrays (eltype
, fmem
, false, pun
,
6501 !pstr
&& TREE_CODE (t
) == RECORD_TYPE
? fld
: pstr
);
6503 if (fmem
->array
!= array
)
6506 if (first
&& !array
&& !ANON_AGGR_TYPE_P (eltype
))
6508 /* Restore the FIRST member reset above if no flexible
6509 array member has been found in this member's struct. */
6510 fmem
->first
= first
;
6513 /* If the member struct contains the first flexible array
6514 member, or if this member is a base class, continue to
6515 the next member and avoid setting the FMEM->NEXT pointer
6522 if (field_nonempty_p (fld
))
6524 /* Remember the first non-static data member. */
6528 /* Remember the first non-static data member after the flexible
6529 array member, if one has been found, or the zero-length array
6530 if it has been found. */
6531 if (fmem
->array
&& !fmem
->after
[bool (pun
)])
6532 fmem
->after
[bool (pun
)] = fld
;
6535 /* Skip non-arrays. */
6536 if (TREE_CODE (fldtype
) != ARRAY_TYPE
)
6539 /* Determine the upper bound of the array if it has one. */
6540 if (TYPE_DOMAIN (fldtype
))
6544 /* Make a record of the zero-length array if either one
6545 such field or a flexible array member has been seen to
6546 handle the pathological and unlikely case of multiple
6548 if (!fmem
->after
[bool (pun
)])
6549 fmem
->after
[bool (pun
)] = fld
;
6551 else if (integer_all_onesp (TYPE_MAX_VALUE (TYPE_DOMAIN (fldtype
))))
6553 /* Remember the first zero-length array unless a flexible array
6554 member has already been seen. */
6556 fmem
->enclosing
= pstr
;
6561 /* Flexible array members have no upper bound. */
6564 /* Replace the zero-length array if it's been stored and
6565 reset the after pointer. */
6566 if (TYPE_DOMAIN (TREE_TYPE (fmem
->array
)))
6568 fmem
->after
[bool (pun
)] = NULL_TREE
;
6570 fmem
->enclosing
= pstr
;
6576 fmem
->enclosing
= pstr
;
6582 /* Diagnose a strictly (by the C standard) invalid use of a struct with
6583 a flexible array member (or the zero-length array extension). */
6586 diagnose_invalid_flexarray (const flexmems_t
*fmem
)
6588 if (fmem
->array
&& fmem
->enclosing
6589 && pedwarn (location_of (fmem
->enclosing
), OPT_Wpedantic
,
6590 TYPE_DOMAIN (TREE_TYPE (fmem
->array
))
6591 ? G_("invalid use of %q#T with a zero-size array "
6593 : G_("invalid use of %q#T with a flexible array member "
6595 DECL_CONTEXT (fmem
->array
),
6596 DECL_CONTEXT (fmem
->enclosing
)))
6597 inform (DECL_SOURCE_LOCATION (fmem
->array
),
6598 "array member %q#D declared here", fmem
->array
);
6601 /* Issue diagnostics for invalid flexible array members or zero-length
6602 arrays that are not the last elements of the containing class or its
6603 base classes or that are its sole members. */
6606 diagnose_flexarrays (tree t
, const flexmems_t
*fmem
)
6611 if (fmem
->first
&& !fmem
->after
[0])
6613 diagnose_invalid_flexarray (fmem
);
6617 /* Has a diagnostic been issued? */
6620 const char *msg
= 0;
6622 if (TYPE_DOMAIN (TREE_TYPE (fmem
->array
)))
6625 msg
= G_("zero-size array member %qD not at end of %q#T");
6626 else if (!fmem
->first
)
6627 msg
= G_("zero-size array member %qD in an otherwise empty %q#T");
6631 location_t loc
= DECL_SOURCE_LOCATION (fmem
->array
);
6633 if (pedwarn (loc
, OPT_Wpedantic
, msg
, fmem
->array
, t
))
6635 inform (location_of (t
), "in the definition of %q#T", t
);
6643 msg
= G_("flexible array member %qD not at end of %q#T");
6644 else if (!fmem
->first
)
6645 msg
= G_("flexible array member %qD in an otherwise empty %q#T");
6649 location_t loc
= DECL_SOURCE_LOCATION (fmem
->array
);
6652 error_at (loc
, msg
, fmem
->array
, t
);
6654 /* In the unlikely event that the member following the flexible
6655 array member is declared in a different class, or the member
6656 overlaps another member of a common union, point to it.
6657 Otherwise it should be obvious. */
6659 && ((DECL_CONTEXT (fmem
->after
[0])
6660 != DECL_CONTEXT (fmem
->array
))))
6662 inform (DECL_SOURCE_LOCATION (fmem
->after
[0]),
6663 "next member %q#D declared here",
6665 inform (location_of (t
), "in the definition of %q#T", t
);
6670 if (!diagd
&& fmem
->array
&& fmem
->enclosing
)
6671 diagnose_invalid_flexarray (fmem
);
6675 /* Recursively check to make sure that any flexible array or zero-length
6676 array members of class T or its bases are valid (i.e., not the sole
6677 non-static data member of T and, if one exists, that it is the last
6678 non-static data member of T and its base classes. FMEM is expected
6679 to be initially null and is used internally by recursive calls to
6680 the function. Issue the appropriate diagnostics for the array member
6681 that fails the checks. */
6684 check_flexarrays (tree t
, flexmems_t
*fmem
/* = NULL */,
6685 bool base_p
/* = false */)
6687 /* Initialize the result of a search for flexible array and zero-length
6688 array members. Avoid doing any work if the most interesting FMEM data
6689 have already been populated. */
6690 flexmems_t flexmems
= flexmems_t ();
6693 else if (fmem
->array
&& fmem
->first
&& fmem
->after
[0])
6696 tree fam
= fmem
->array
;
6698 /* Recursively check the primary base class first. */
6699 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t
))
6701 tree basetype
= BINFO_TYPE (CLASSTYPE_PRIMARY_BINFO (t
));
6702 check_flexarrays (basetype
, fmem
, true);
6705 /* Recursively check the base classes. */
6706 int nbases
= TYPE_BINFO (t
) ? BINFO_N_BASE_BINFOS (TYPE_BINFO (t
)) : 0;
6707 for (int i
= 0; i
< nbases
; ++i
)
6709 tree base_binfo
= BINFO_BASE_BINFO (TYPE_BINFO (t
), i
);
6711 /* The primary base class was already checked above. */
6712 if (base_binfo
== CLASSTYPE_PRIMARY_BINFO (t
))
6715 /* Virtual base classes are at the end. */
6716 if (BINFO_VIRTUAL_P (base_binfo
))
6719 /* Check the base class. */
6720 check_flexarrays (BINFO_TYPE (base_binfo
), fmem
, /*base_p=*/true);
6723 if (fmem
== &flexmems
)
6725 /* Check virtual base classes only once per derived class.
6726 I.e., this check is not performed recursively for base
6730 vec
<tree
, va_gc
> *vbases
;
6731 for (vbases
= CLASSTYPE_VBASECLASSES (t
), i
= 0;
6732 vec_safe_iterate (vbases
, i
, &base_binfo
); i
++)
6734 /* Check the virtual base class. */
6735 tree basetype
= TREE_TYPE (base_binfo
);
6737 check_flexarrays (basetype
, fmem
, /*base_p=*/true);
6741 /* Is the type unnamed (and therefore a member of it potentially
6742 an anonymous struct or union)? */
6743 bool maybe_anon_p
= TYPE_UNNAMED_P (t
);
6745 /* Search the members of the current (possibly derived) class, skipping
6746 unnamed structs and unions since those could be anonymous. */
6747 if (fmem
!= &flexmems
|| !maybe_anon_p
)
6748 find_flexarrays (t
, fmem
, base_p
|| fam
!= fmem
->array
);
6750 if (fmem
== &flexmems
&& !maybe_anon_p
)
6752 /* Issue diagnostics for invalid flexible and zero-length array
6753 members found in base classes or among the members of the current
6754 class. Ignore anonymous structs and unions whose members are
6755 considered to be members of the enclosing class and thus will
6756 be diagnosed when checking it. */
6757 diagnose_flexarrays (t
, fmem
);
6761 /* Perform processing required when the definition of T (a class type)
6762 is complete. Diagnose invalid definitions of flexible array members
6763 and zero-size arrays. */
6766 finish_struct_1 (tree t
)
6769 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
6770 tree virtuals
= NULL_TREE
;
6772 if (COMPLETE_TYPE_P (t
))
6774 gcc_assert (MAYBE_CLASS_TYPE_P (t
));
6775 error ("redefinition of %q#T", t
);
6780 /* If this type was previously laid out as a forward reference,
6781 make sure we lay it out again. */
6782 TYPE_SIZE (t
) = NULL_TREE
;
6783 CLASSTYPE_PRIMARY_BINFO (t
) = NULL_TREE
;
6785 /* Make assumptions about the class; we'll reset the flags if
6787 CLASSTYPE_EMPTY_P (t
) = 1;
6788 CLASSTYPE_NEARLY_EMPTY_P (t
) = 1;
6789 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t
) = 0;
6790 CLASSTYPE_LITERAL_P (t
) = true;
6792 /* Do end-of-class semantic processing: checking the validity of the
6793 bases and members and add implicitly generated methods. */
6794 check_bases_and_members (t
);
6796 /* Find the key method. */
6797 if (TYPE_CONTAINS_VPTR_P (t
))
6799 /* The Itanium C++ ABI permits the key method to be chosen when
6800 the class is defined -- even though the key method so
6801 selected may later turn out to be an inline function. On
6802 some systems (such as ARM Symbian OS) the key method cannot
6803 be determined until the end of the translation unit. On such
6804 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
6805 will cause the class to be added to KEYED_CLASSES. Then, in
6806 finish_file we will determine the key method. */
6807 if (targetm
.cxx
.key_method_may_be_inline ())
6808 determine_key_method (t
);
6810 /* If a polymorphic class has no key method, we may emit the vtable
6811 in every translation unit where the class definition appears. If
6812 we're devirtualizing, we can look into the vtable even if we
6813 aren't emitting it. */
6814 if (!CLASSTYPE_KEY_METHOD (t
))
6815 vec_safe_push (keyed_classes
, t
);
6818 /* Layout the class itself. */
6819 layout_class_type (t
, &virtuals
);
6820 /* COMPLETE_TYPE_P is now true. */
6822 set_class_bindings (t
);
6824 if (CLASSTYPE_AS_BASE (t
) != t
)
6825 /* We use the base type for trivial assignments, and hence it
6827 compute_record_mode (CLASSTYPE_AS_BASE (t
));
6829 /* With the layout complete, check for flexible array members and
6830 zero-length arrays that might overlap other members in the final
6832 check_flexarrays (t
);
6834 virtuals
= modify_all_vtables (t
, nreverse (virtuals
));
6836 /* If necessary, create the primary vtable for this class. */
6837 if (virtuals
|| TYPE_CONTAINS_VPTR_P (t
))
6839 /* We must enter these virtuals into the table. */
6840 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t
))
6841 build_primary_vtable (NULL_TREE
, t
);
6842 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t
)))
6843 /* Here we know enough to change the type of our virtual
6844 function table, but we will wait until later this function. */
6845 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t
), t
);
6847 /* If we're warning about ABI tags, check the types of the new
6848 virtual functions. */
6850 for (tree v
= virtuals
; v
; v
= TREE_CHAIN (v
))
6851 check_abi_tags (t
, TREE_VALUE (v
));
6854 if (TYPE_CONTAINS_VPTR_P (t
))
6859 if (BINFO_VTABLE (TYPE_BINFO (t
)))
6860 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t
))));
6861 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t
))
6862 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t
)) == NULL_TREE
);
6864 /* Add entries for virtual functions introduced by this class. */
6865 BINFO_VIRTUALS (TYPE_BINFO (t
))
6866 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t
)), virtuals
);
6868 /* Set DECL_VINDEX for all functions declared in this class. */
6869 for (vindex
= 0, fn
= BINFO_VIRTUALS (TYPE_BINFO (t
));
6871 fn
= TREE_CHAIN (fn
),
6872 vindex
+= (TARGET_VTABLE_USES_DESCRIPTORS
6873 ? TARGET_VTABLE_USES_DESCRIPTORS
: 1))
6875 tree fndecl
= BV_FN (fn
);
6877 if (DECL_THUNK_P (fndecl
))
6878 /* A thunk. We should never be calling this entry directly
6879 from this vtable -- we'd use the entry for the non
6880 thunk base function. */
6881 DECL_VINDEX (fndecl
) = NULL_TREE
;
6882 else if (TREE_CODE (DECL_VINDEX (fndecl
)) != INTEGER_CST
)
6883 DECL_VINDEX (fndecl
) = build_int_cst (NULL_TREE
, vindex
);
6887 finish_struct_bits (t
);
6889 set_method_tm_attributes (t
);
6890 if (flag_openmp
|| flag_openmp_simd
)
6891 finish_omp_declare_simd_methods (t
);
6893 /* Clear DECL_IN_AGGR_P for all member functions. Complete the rtl
6894 for any static member objects of the type we're working on. */
6895 for (x
= TYPE_FIELDS (t
); x
; x
= DECL_CHAIN (x
))
6896 if (DECL_DECLARES_FUNCTION_P (x
))
6897 DECL_IN_AGGR_P (x
) = false;
6898 else if (VAR_P (x
) && TREE_STATIC (x
)
6899 && TREE_TYPE (x
) != error_mark_node
6900 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x
)), t
))
6901 SET_DECL_MODE (x
, TYPE_MODE (t
));
6903 /* Complain if one of the field types requires lower visibility. */
6904 constrain_class_visibility (t
);
6906 /* Make the rtl for any new vtables we have created, and unmark
6907 the base types we marked. */
6910 /* Build the VTT for T. */
6914 && TYPE_POLYMORPHIC_P (t
) && accessible_nvdtor_p (t
)
6915 && !CLASSTYPE_FINAL (t
))
6916 warning (OPT_Wnon_virtual_dtor
,
6917 "%q#T has virtual functions and accessible"
6918 " non-virtual destructor", t
);
6922 if (warn_overloaded_virtual
)
6925 /* Class layout, assignment of virtual table slots, etc., is now
6926 complete. Give the back end a chance to tweak the visibility of
6927 the class or perform any other required target modifications. */
6928 targetm
.cxx
.adjust_class_at_definition (t
);
6930 maybe_suppress_debug_info (t
);
6932 if (flag_vtable_verify
)
6933 vtv_save_class_info (t
);
6935 dump_class_hierarchy (t
);
6937 /* Finish debugging output for this type. */
6938 rest_of_type_compilation (t
, ! LOCAL_CLASS_P (t
));
6940 if (TYPE_TRANSPARENT_AGGR (t
))
6942 tree field
= first_field (t
);
6943 if (field
== NULL_TREE
|| error_operand_p (field
))
6945 error ("type transparent %q#T does not have any fields", t
);
6946 TYPE_TRANSPARENT_AGGR (t
) = 0;
6948 else if (DECL_ARTIFICIAL (field
))
6950 if (DECL_FIELD_IS_BASE (field
))
6951 error ("type transparent class %qT has base classes", t
);
6954 gcc_checking_assert (DECL_VIRTUAL_P (field
));
6955 error ("type transparent class %qT has virtual functions", t
);
6957 TYPE_TRANSPARENT_AGGR (t
) = 0;
6959 else if (TYPE_MODE (t
) != DECL_MODE (field
))
6961 error ("type transparent %q#T cannot be made transparent because "
6962 "the type of the first field has a different ABI from the "
6963 "class overall", t
);
6964 TYPE_TRANSPARENT_AGGR (t
) = 0;
6969 /* When T was built up, the member declarations were added in reverse
6970 order. Rearrange them to declaration order. */
6973 unreverse_member_declarations (tree t
)
6979 /* The following lists are all in reverse order. Put them in
6980 declaration order now. */
6981 CLASSTYPE_DECL_LIST (t
) = nreverse (CLASSTYPE_DECL_LIST (t
));
6983 /* For the TYPE_FIELDS, only the non TYPE_DECLs are in reverse
6984 order, so we can't just use nreverse. Due to stat_hack
6985 chicanery in finish_member_declaration. */
6987 for (x
= TYPE_FIELDS (t
);
6988 x
&& TREE_CODE (x
) != TYPE_DECL
;
6991 next
= DECL_CHAIN (x
);
6992 DECL_CHAIN (x
) = prev
;
6998 DECL_CHAIN (TYPE_FIELDS (t
)) = x
;
6999 TYPE_FIELDS (t
) = prev
;
7004 finish_struct (tree t
, tree attributes
)
7006 location_t saved_loc
= input_location
;
7008 /* Now that we've got all the field declarations, reverse everything
7010 unreverse_member_declarations (t
);
7012 cplus_decl_attributes (&t
, attributes
, (int) ATTR_FLAG_TYPE_IN_PLACE
);
7013 fixup_attribute_variants (t
);
7015 /* Nadger the current location so that diagnostics point to the start of
7016 the struct, not the end. */
7017 input_location
= DECL_SOURCE_LOCATION (TYPE_NAME (t
));
7019 if (processing_template_decl
)
7023 /* We need to add the target functions of USING_DECLS, so that
7024 they can be found when the using declaration is not
7025 instantiated yet. */
7026 for (x
= TYPE_FIELDS (t
); x
; x
= DECL_CHAIN (x
))
7027 if (TREE_CODE (x
) == USING_DECL
)
7029 tree fn
= strip_using_decl (x
);
7031 for (lkp_iterator
iter (fn
); iter
; ++iter
)
7032 add_method (t
, *iter
, true);
7034 else if (DECL_DECLARES_FUNCTION_P (x
))
7035 DECL_IN_AGGR_P (x
) = false;
7037 TYPE_SIZE (t
) = bitsize_zero_node
;
7038 TYPE_SIZE_UNIT (t
) = size_zero_node
;
7039 /* COMPLETE_TYPE_P is now true. */
7041 set_class_bindings (t
);
7043 /* We need to emit an error message if this type was used as a parameter
7044 and it is an abstract type, even if it is a template. We construct
7045 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
7046 account and we call complete_vars with this type, which will check
7047 the PARM_DECLS. Note that while the type is being defined,
7048 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
7049 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
7050 CLASSTYPE_PURE_VIRTUALS (t
) = NULL
;
7051 for (x
= TYPE_FIELDS (t
); x
; x
= DECL_CHAIN (x
))
7052 if (TREE_CODE (x
) == FUNCTION_DECL
&& DECL_PURE_VIRTUAL_P (x
))
7053 vec_safe_push (CLASSTYPE_PURE_VIRTUALS (t
), x
);
7056 /* Remember current #pragma pack value. */
7057 TYPE_PRECISION (t
) = maximum_field_alignment
;
7059 /* Fix up any variants we've already built. */
7060 for (x
= TYPE_NEXT_VARIANT (t
); x
; x
= TYPE_NEXT_VARIANT (x
))
7062 TYPE_SIZE (x
) = TYPE_SIZE (t
);
7063 TYPE_SIZE_UNIT (x
) = TYPE_SIZE_UNIT (t
);
7064 TYPE_FIELDS (x
) = TYPE_FIELDS (t
);
7068 finish_struct_1 (t
);
7069 /* COMPLETE_TYPE_P is now true. */
7071 maybe_warn_about_overly_private_class (t
);
7073 if (is_std_init_list (t
))
7075 /* People keep complaining that the compiler crashes on an invalid
7076 definition of initializer_list, so I guess we should explicitly
7077 reject it. What the compiler internals care about is that it's a
7078 template and has a pointer field followed by an integer field. */
7080 if (processing_template_decl
)
7082 tree f
= next_initializable_field (TYPE_FIELDS (t
));
7083 if (f
&& TREE_CODE (TREE_TYPE (f
)) == POINTER_TYPE
)
7085 f
= next_initializable_field (DECL_CHAIN (f
));
7086 if (f
&& same_type_p (TREE_TYPE (f
), size_type_node
))
7091 fatal_error (input_location
,
7092 "definition of std::initializer_list does not match "
7093 "#include <initializer_list>");
7096 input_location
= saved_loc
;
7098 TYPE_BEING_DEFINED (t
) = 0;
7100 if (current_class_type
)
7103 error ("trying to finish struct, but kicked out due to previous parse errors");
7105 if (processing_template_decl
&& at_function_scope_p ()
7106 /* Lambdas are defined by the LAMBDA_EXPR. */
7107 && !LAMBDA_TYPE_P (t
))
7108 add_stmt (build_min (TAG_DEFN
, t
));
7113 /* Hash table to avoid endless recursion when handling references. */
7114 static hash_table
<nofree_ptr_hash
<tree_node
> > *fixed_type_or_null_ref_ht
;
7116 /* Return the dynamic type of INSTANCE, if known.
7117 Used to determine whether the virtual function table is needed
7120 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
7121 of our knowledge of its type. *NONNULL should be initialized
7122 before this function is called. */
7125 fixed_type_or_null (tree instance
, int *nonnull
, int *cdtorp
)
7127 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
7129 switch (TREE_CODE (instance
))
7132 if (POINTER_TYPE_P (TREE_TYPE (instance
)))
7135 return RECUR (TREE_OPERAND (instance
, 0));
7138 /* This is a call to a constructor, hence it's never zero. */
7139 if (TREE_HAS_CONSTRUCTOR (instance
))
7143 return TREE_TYPE (instance
);
7148 /* This is a call to a constructor, hence it's never zero. */
7149 if (TREE_HAS_CONSTRUCTOR (instance
))
7153 return TREE_TYPE (instance
);
7155 return RECUR (TREE_OPERAND (instance
, 0));
7157 case POINTER_PLUS_EXPR
:
7160 if (TREE_CODE (TREE_OPERAND (instance
, 0)) == ADDR_EXPR
)
7161 return RECUR (TREE_OPERAND (instance
, 0));
7162 if (TREE_CODE (TREE_OPERAND (instance
, 1)) == INTEGER_CST
)
7163 /* Propagate nonnull. */
7164 return RECUR (TREE_OPERAND (instance
, 0));
7169 return RECUR (TREE_OPERAND (instance
, 0));
7172 instance
= TREE_OPERAND (instance
, 0);
7175 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
7176 with a real object -- given &p->f, p can still be null. */
7177 tree t
= get_base_address (instance
);
7178 /* ??? Probably should check DECL_WEAK here. */
7179 if (t
&& DECL_P (t
))
7182 return RECUR (instance
);
7185 /* If this component is really a base class reference, then the field
7186 itself isn't definitive. */
7187 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance
, 1)))
7188 return RECUR (TREE_OPERAND (instance
, 0));
7189 return RECUR (TREE_OPERAND (instance
, 1));
7193 if (TREE_CODE (TREE_TYPE (instance
)) == ARRAY_TYPE
7194 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance
))))
7198 return TREE_TYPE (TREE_TYPE (instance
));
7204 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance
)))
7208 return TREE_TYPE (instance
);
7210 else if (instance
== current_class_ptr
)
7215 /* if we're in a ctor or dtor, we know our type. If
7216 current_class_ptr is set but we aren't in a function, we're in
7217 an NSDMI (and therefore a constructor). */
7218 if (current_scope () != current_function_decl
7219 || (DECL_LANG_SPECIFIC (current_function_decl
)
7220 && (DECL_CONSTRUCTOR_P (current_function_decl
)
7221 || DECL_DESTRUCTOR_P (current_function_decl
))))
7225 return TREE_TYPE (TREE_TYPE (instance
));
7228 else if (TREE_CODE (TREE_TYPE (instance
)) == REFERENCE_TYPE
)
7230 /* We only need one hash table because it is always left empty. */
7231 if (!fixed_type_or_null_ref_ht
)
7232 fixed_type_or_null_ref_ht
7233 = new hash_table
<nofree_ptr_hash
<tree_node
> > (37);
7235 /* Reference variables should be references to objects. */
7239 /* Enter the INSTANCE in a table to prevent recursion; a
7240 variable's initializer may refer to the variable
7242 if (VAR_P (instance
)
7243 && DECL_INITIAL (instance
)
7244 && !type_dependent_expression_p_push (DECL_INITIAL (instance
))
7245 && !fixed_type_or_null_ref_ht
->find (instance
))
7250 slot
= fixed_type_or_null_ref_ht
->find_slot (instance
, INSERT
);
7252 type
= RECUR (DECL_INITIAL (instance
));
7253 fixed_type_or_null_ref_ht
->remove_elt (instance
);
7266 /* Return nonzero if the dynamic type of INSTANCE is known, and
7267 equivalent to the static type. We also handle the case where
7268 INSTANCE is really a pointer. Return negative if this is a
7269 ctor/dtor. There the dynamic type is known, but this might not be
7270 the most derived base of the original object, and hence virtual
7271 bases may not be laid out according to this type.
7273 Used to determine whether the virtual function table is needed
7276 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
7277 of our knowledge of its type. *NONNULL should be initialized
7278 before this function is called. */
7281 resolves_to_fixed_type_p (tree instance
, int* nonnull
)
7283 tree t
= TREE_TYPE (instance
);
7287 /* processing_template_decl can be false in a template if we're in
7288 instantiate_non_dependent_expr, but we still want to suppress
7290 if (in_template_function ())
7292 /* In a template we only care about the type of the result. */
7298 fixed
= fixed_type_or_null (instance
, nonnull
, &cdtorp
);
7299 if (fixed
== NULL_TREE
)
7301 if (POINTER_TYPE_P (t
))
7303 if (!same_type_ignoring_top_level_qualifiers_p (t
, fixed
))
7305 return cdtorp
? -1 : 1;
7310 init_class_processing (void)
7312 current_class_depth
= 0;
7313 current_class_stack_size
= 10;
7315 = XNEWVEC (struct class_stack_node
, current_class_stack_size
);
7316 vec_alloc (local_classes
, 8);
7317 sizeof_biggest_empty_class
= size_zero_node
;
7319 ridpointers
[(int) RID_PUBLIC
] = access_public_node
;
7320 ridpointers
[(int) RID_PRIVATE
] = access_private_node
;
7321 ridpointers
[(int) RID_PROTECTED
] = access_protected_node
;
7324 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
7327 restore_class_cache (void)
7331 /* We are re-entering the same class we just left, so we don't
7332 have to search the whole inheritance matrix to find all the
7333 decls to bind again. Instead, we install the cached
7334 class_shadowed list and walk through it binding names. */
7335 push_binding_level (previous_class_level
);
7336 class_binding_level
= previous_class_level
;
7337 /* Restore IDENTIFIER_TYPE_VALUE. */
7338 for (type
= class_binding_level
->type_shadowed
;
7340 type
= TREE_CHAIN (type
))
7341 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type
), TREE_TYPE (type
));
7344 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
7345 appropriate for TYPE.
7347 So that we may avoid calls to lookup_name, we cache the _TYPE
7348 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
7350 For multiple inheritance, we perform a two-pass depth-first search
7351 of the type lattice. */
7354 pushclass (tree type
)
7356 class_stack_node_t csn
;
7358 type
= TYPE_MAIN_VARIANT (type
);
7360 /* Make sure there is enough room for the new entry on the stack. */
7361 if (current_class_depth
+ 1 >= current_class_stack_size
)
7363 current_class_stack_size
*= 2;
7365 = XRESIZEVEC (struct class_stack_node
, current_class_stack
,
7366 current_class_stack_size
);
7369 /* Insert a new entry on the class stack. */
7370 csn
= current_class_stack
+ current_class_depth
;
7371 csn
->name
= current_class_name
;
7372 csn
->type
= current_class_type
;
7373 csn
->access
= current_access_specifier
;
7374 csn
->names_used
= 0;
7376 current_class_depth
++;
7378 /* Now set up the new type. */
7379 current_class_name
= TYPE_NAME (type
);
7380 if (TREE_CODE (current_class_name
) == TYPE_DECL
)
7381 current_class_name
= DECL_NAME (current_class_name
);
7382 current_class_type
= type
;
7384 /* By default, things in classes are private, while things in
7385 structures or unions are public. */
7386 current_access_specifier
= (CLASSTYPE_DECLARED_CLASS (type
)
7387 ? access_private_node
7388 : access_public_node
);
7390 if (previous_class_level
7391 && type
!= previous_class_level
->this_entity
7392 && current_class_depth
== 1)
7394 /* Forcibly remove any old class remnants. */
7395 invalidate_class_lookup_cache ();
7398 if (!previous_class_level
7399 || type
!= previous_class_level
->this_entity
7400 || current_class_depth
> 1)
7403 restore_class_cache ();
7406 /* When we exit a toplevel class scope, we save its binding level so
7407 that we can restore it quickly. Here, we've entered some other
7408 class, so we must invalidate our cache. */
7411 invalidate_class_lookup_cache (void)
7413 previous_class_level
= NULL
;
7416 /* Get out of the current class scope. If we were in a class scope
7417 previously, that is the one popped to. */
7424 current_class_depth
--;
7425 current_class_name
= current_class_stack
[current_class_depth
].name
;
7426 current_class_type
= current_class_stack
[current_class_depth
].type
;
7427 current_access_specifier
= current_class_stack
[current_class_depth
].access
;
7428 if (current_class_stack
[current_class_depth
].names_used
)
7429 splay_tree_delete (current_class_stack
[current_class_depth
].names_used
);
7432 /* Mark the top of the class stack as hidden. */
7435 push_class_stack (void)
7437 if (current_class_depth
)
7438 ++current_class_stack
[current_class_depth
- 1].hidden
;
7441 /* Mark the top of the class stack as un-hidden. */
7444 pop_class_stack (void)
7446 if (current_class_depth
)
7447 --current_class_stack
[current_class_depth
- 1].hidden
;
7450 /* Returns 1 if the class type currently being defined is either T or
7451 a nested type of T. Returns the type from the current_class_stack,
7452 which might be equivalent to but not equal to T in case of
7453 constrained partial specializations. */
7456 currently_open_class (tree t
)
7460 if (!CLASS_TYPE_P (t
))
7463 t
= TYPE_MAIN_VARIANT (t
);
7465 /* We start looking from 1 because entry 0 is from global scope,
7467 for (i
= current_class_depth
; i
> 0; --i
)
7470 if (i
== current_class_depth
)
7471 c
= current_class_type
;
7474 if (current_class_stack
[i
].hidden
)
7476 c
= current_class_stack
[i
].type
;
7480 if (same_type_p (c
, t
))
7486 /* If either current_class_type or one of its enclosing classes are derived
7487 from T, return the appropriate type. Used to determine how we found
7488 something via unqualified lookup. */
7491 currently_open_derived_class (tree t
)
7495 /* The bases of a dependent type are unknown. */
7496 if (dependent_type_p (t
))
7499 if (!current_class_type
)
7502 if (DERIVED_FROM_P (t
, current_class_type
))
7503 return current_class_type
;
7505 for (i
= current_class_depth
- 1; i
> 0; --i
)
7507 if (current_class_stack
[i
].hidden
)
7509 if (DERIVED_FROM_P (t
, current_class_stack
[i
].type
))
7510 return current_class_stack
[i
].type
;
7516 /* Return the outermost enclosing class type that is still open, or
7520 outermost_open_class (void)
7522 if (!current_class_type
)
7525 if (TYPE_BEING_DEFINED (current_class_type
))
7526 r
= current_class_type
;
7527 for (int i
= current_class_depth
- 1; i
> 0; --i
)
7529 if (current_class_stack
[i
].hidden
)
7531 tree t
= current_class_stack
[i
].type
;
7532 if (!TYPE_BEING_DEFINED (t
))
7539 /* Returns the innermost class type which is not a lambda closure type. */
7542 current_nonlambda_class_type (void)
7544 tree type
= current_class_type
;
7545 while (type
&& LAMBDA_TYPE_P (type
))
7546 type
= decl_type_context (TYPE_NAME (type
));
7550 /* When entering a class scope, all enclosing class scopes' names with
7551 static meaning (static variables, static functions, types and
7552 enumerators) have to be visible. This recursive function calls
7553 pushclass for all enclosing class contexts until global or a local
7554 scope is reached. TYPE is the enclosed class. */
7557 push_nested_class (tree type
)
7559 /* A namespace might be passed in error cases, like A::B:C. */
7560 if (type
== NULL_TREE
7561 || !CLASS_TYPE_P (type
))
7564 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type
)));
7569 /* Undoes a push_nested_class call. */
7572 pop_nested_class (void)
7574 tree context
= DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type
));
7577 if (context
&& CLASS_TYPE_P (context
))
7578 pop_nested_class ();
7581 /* Returns the number of extern "LANG" blocks we are nested within. */
7584 current_lang_depth (void)
7586 return vec_safe_length (current_lang_base
);
7589 /* Set global variables CURRENT_LANG_NAME to appropriate value
7590 so that behavior of name-mangling machinery is correct. */
7593 push_lang_context (tree name
)
7595 vec_safe_push (current_lang_base
, current_lang_name
);
7597 if (name
== lang_name_cplusplus
)
7598 current_lang_name
= name
;
7599 else if (name
== lang_name_c
)
7600 current_lang_name
= name
;
7602 error ("language string %<\"%E\"%> not recognized", name
);
7605 /* Get out of the current language scope. */
7608 pop_lang_context (void)
7610 current_lang_name
= current_lang_base
->pop ();
7613 /* Type instantiation routines. */
7615 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
7616 matches the TARGET_TYPE. If there is no satisfactory match, return
7617 error_mark_node, and issue an error & warning messages under
7618 control of FLAGS. Permit pointers to member function if FLAGS
7619 permits. If TEMPLATE_ONLY, the name of the overloaded function was
7620 a template-id, and EXPLICIT_TARGS are the explicitly provided
7623 If OVERLOAD is for one or more member functions, then ACCESS_PATH
7624 is the base path used to reference those member functions. If
7625 the address is resolved to a member function, access checks will be
7626 performed and errors issued if appropriate. */
7629 resolve_address_of_overloaded_function (tree target_type
,
7631 tsubst_flags_t complain
,
7633 tree explicit_targs
,
7636 /* Here's what the standard says:
7640 If the name is a function template, template argument deduction
7641 is done, and if the argument deduction succeeds, the deduced
7642 arguments are used to generate a single template function, which
7643 is added to the set of overloaded functions considered.
7645 Non-member functions and static member functions match targets of
7646 type "pointer-to-function" or "reference-to-function." Nonstatic
7647 member functions match targets of type "pointer-to-member
7648 function;" the function type of the pointer to member is used to
7649 select the member function from the set of overloaded member
7650 functions. If a nonstatic member function is selected, the
7651 reference to the overloaded function name is required to have the
7652 form of a pointer to member as described in 5.3.1.
7654 If more than one function is selected, any template functions in
7655 the set are eliminated if the set also contains a non-template
7656 function, and any given template function is eliminated if the
7657 set contains a second template function that is more specialized
7658 than the first according to the partial ordering rules 14.5.5.2.
7659 After such eliminations, if any, there shall remain exactly one
7660 selected function. */
7663 /* We store the matches in a TREE_LIST rooted here. The functions
7664 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
7665 interoperability with most_specialized_instantiation. */
7666 tree matches
= NULL_TREE
;
7668 tree target_fn_type
;
7670 /* By the time we get here, we should be seeing only real
7671 pointer-to-member types, not the internal POINTER_TYPE to
7672 METHOD_TYPE representation. */
7673 gcc_assert (!TYPE_PTR_P (target_type
)
7674 || TREE_CODE (TREE_TYPE (target_type
)) != METHOD_TYPE
);
7676 gcc_assert (is_overloaded_fn (overload
));
7678 /* Check that the TARGET_TYPE is reasonable. */
7679 if (TYPE_PTRFN_P (target_type
)
7680 || TYPE_REFFN_P (target_type
))
7682 else if (TYPE_PTRMEMFUNC_P (target_type
))
7683 /* This is OK, too. */
7685 else if (TREE_CODE (target_type
) == FUNCTION_TYPE
)
7686 /* This is OK, too. This comes from a conversion to reference
7688 target_type
= build_reference_type (target_type
);
7691 if (complain
& tf_error
)
7692 error ("cannot resolve overloaded function %qD based on"
7693 " conversion to type %qT",
7694 OVL_NAME (overload
), target_type
);
7695 return error_mark_node
;
7698 /* Non-member functions and static member functions match targets of type
7699 "pointer-to-function" or "reference-to-function." Nonstatic member
7700 functions match targets of type "pointer-to-member-function;" the
7701 function type of the pointer to member is used to select the member
7702 function from the set of overloaded member functions.
7704 So figure out the FUNCTION_TYPE that we want to match against. */
7705 target_fn_type
= static_fn_type (target_type
);
7707 /* If we can find a non-template function that matches, we can just
7708 use it. There's no point in generating template instantiations
7709 if we're just going to throw them out anyhow. But, of course, we
7710 can only do this when we don't *need* a template function. */
7712 for (lkp_iterator
iter (overload
); iter
; ++iter
)
7716 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
7717 /* We're not looking for templates just yet. */
7720 if ((TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
) != is_ptrmem
)
7721 /* We're looking for a non-static member, and this isn't
7722 one, or vice versa. */
7725 /* In C++17 we need the noexcept-qualifier to compare types. */
7726 if (flag_noexcept_type
7727 && !maybe_instantiate_noexcept (fn
, complain
))
7730 /* See if there's a match. */
7731 tree fntype
= static_fn_type (fn
);
7732 if (same_type_p (target_fn_type
, fntype
)
7733 || fnptr_conv_p (target_fn_type
, fntype
))
7734 matches
= tree_cons (fn
, NULL_TREE
, matches
);
7737 /* Now, if we've already got a match (or matches), there's no need
7738 to proceed to the template functions. But, if we don't have a
7739 match we need to look at them, too. */
7742 tree target_arg_types
;
7743 tree target_ret_type
;
7745 unsigned int nargs
, ia
;
7748 target_arg_types
= TYPE_ARG_TYPES (target_fn_type
);
7749 target_ret_type
= TREE_TYPE (target_fn_type
);
7751 nargs
= list_length (target_arg_types
);
7752 args
= XALLOCAVEC (tree
, nargs
);
7753 for (arg
= target_arg_types
, ia
= 0;
7754 arg
!= NULL_TREE
&& arg
!= void_list_node
;
7755 arg
= TREE_CHAIN (arg
), ++ia
)
7756 args
[ia
] = TREE_VALUE (arg
);
7759 for (lkp_iterator
iter (overload
); iter
; ++iter
)
7765 if (TREE_CODE (fn
) != TEMPLATE_DECL
)
7766 /* We're only looking for templates. */
7769 if ((TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
7771 /* We're not looking for a non-static member, and this is
7772 one, or vice versa. */
7775 tree ret
= target_ret_type
;
7777 /* If the template has a deduced return type, don't expose it to
7778 template argument deduction. */
7779 if (undeduced_auto_decl (fn
))
7782 /* Try to do argument deduction. */
7783 targs
= make_tree_vec (DECL_NTPARMS (fn
));
7784 instantiation
= fn_type_unification (fn
, explicit_targs
, targs
, args
,
7786 DEDUCE_EXACT
, LOOKUP_NORMAL
,
7788 if (instantiation
== error_mark_node
)
7789 /* Instantiation failed. */
7792 /* Constraints must be satisfied. This is done before
7793 return type deduction since that instantiates the
7795 if (flag_concepts
&& !constraints_satisfied_p (instantiation
))
7798 /* And now force instantiation to do return type deduction. */
7799 if (undeduced_auto_decl (instantiation
))
7802 instantiate_decl (instantiation
, /*defer*/false, /*class*/false);
7805 require_deduced_type (instantiation
);
7808 /* In C++17 we need the noexcept-qualifier to compare types. */
7809 if (flag_noexcept_type
)
7810 maybe_instantiate_noexcept (instantiation
, complain
);
7812 /* See if there's a match. */
7813 tree fntype
= static_fn_type (instantiation
);
7814 if (same_type_p (target_fn_type
, fntype
)
7815 || fnptr_conv_p (target_fn_type
, fntype
))
7816 matches
= tree_cons (instantiation
, fn
, matches
);
7819 /* Now, remove all but the most specialized of the matches. */
7822 tree match
= most_specialized_instantiation (matches
);
7824 if (match
!= error_mark_node
)
7825 matches
= tree_cons (TREE_PURPOSE (match
),
7831 /* Now we should have exactly one function in MATCHES. */
7832 if (matches
== NULL_TREE
)
7834 /* There were *no* matches. */
7835 if (complain
& tf_error
)
7837 error ("no matches converting function %qD to type %q#T",
7838 OVL_NAME (overload
), target_type
);
7840 print_candidates (overload
);
7842 return error_mark_node
;
7844 else if (TREE_CHAIN (matches
))
7846 /* There were too many matches. First check if they're all
7847 the same function. */
7848 tree match
= NULL_TREE
;
7850 fn
= TREE_PURPOSE (matches
);
7852 /* For multi-versioned functions, more than one match is just fine and
7853 decls_match will return false as they are different. */
7854 for (match
= TREE_CHAIN (matches
); match
; match
= TREE_CHAIN (match
))
7855 if (!decls_match (fn
, TREE_PURPOSE (match
))
7856 && !targetm
.target_option
.function_versions
7857 (fn
, TREE_PURPOSE (match
)))
7862 if (complain
& tf_error
)
7864 error ("converting overloaded function %qD to type %q#T is ambiguous",
7865 OVL_NAME (overload
), target_type
);
7867 /* Since print_candidates expects the functions in the
7868 TREE_VALUE slot, we flip them here. */
7869 for (match
= matches
; match
; match
= TREE_CHAIN (match
))
7870 TREE_VALUE (match
) = TREE_PURPOSE (match
);
7872 print_candidates (matches
);
7875 return error_mark_node
;
7879 /* Good, exactly one match. Now, convert it to the correct type. */
7880 fn
= TREE_PURPOSE (matches
);
7882 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
)
7883 && !(complain
& tf_ptrmem_ok
) && !flag_ms_extensions
)
7885 static int explained
;
7887 if (!(complain
& tf_error
))
7888 return error_mark_node
;
7890 permerror (input_location
, "assuming pointer to member %qD", fn
);
7893 inform (input_location
, "(a pointer to member can only be formed with %<&%E%>)", fn
);
7898 /* If a pointer to a function that is multi-versioned is requested, the
7899 pointer to the dispatcher function is returned instead. This works
7900 well because indirectly calling the function will dispatch the right
7901 function version at run-time. */
7902 if (DECL_FUNCTION_VERSIONED (fn
))
7904 fn
= get_function_version_dispatcher (fn
);
7906 return error_mark_node
;
7907 /* Mark all the versions corresponding to the dispatcher as used. */
7908 if (!(complain
& tf_conv
))
7909 mark_versions_used (fn
);
7912 /* If we're doing overload resolution purely for the purpose of
7913 determining conversion sequences, we should not consider the
7914 function used. If this conversion sequence is selected, the
7915 function will be marked as used at this point. */
7916 if (!(complain
& tf_conv
))
7918 /* Make =delete work with SFINAE. */
7919 if (DECL_DELETED_FN (fn
) && !(complain
& tf_error
))
7920 return error_mark_node
;
7921 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
7922 return error_mark_node
;
7925 /* We could not check access to member functions when this
7926 expression was originally created since we did not know at that
7927 time to which function the expression referred. */
7928 if (DECL_FUNCTION_MEMBER_P (fn
))
7930 gcc_assert (access_path
);
7931 perform_or_defer_access_check (access_path
, fn
, fn
, complain
);
7934 if (TYPE_PTRFN_P (target_type
) || TYPE_PTRMEMFUNC_P (target_type
))
7935 return cp_build_addr_expr (fn
, complain
);
7938 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
7939 will mark the function as addressed, but here we must do it
7941 cxx_mark_addressable (fn
);
7947 /* This function will instantiate the type of the expression given in
7948 RHS to match the type of LHSTYPE. If errors exist, then return
7949 error_mark_node. COMPLAIN is a bit mask. If TF_ERROR is set, then
7950 we complain on errors. If we are not complaining, never modify rhs,
7951 as overload resolution wants to try many possible instantiations, in
7952 the hope that at least one will work.
7954 For non-recursive calls, LHSTYPE should be a function, pointer to
7955 function, or a pointer to member function. */
7958 instantiate_type (tree lhstype
, tree rhs
, tsubst_flags_t complain
)
7960 tsubst_flags_t complain_in
= complain
;
7961 tree access_path
= NULL_TREE
;
7963 complain
&= ~tf_ptrmem_ok
;
7965 if (lhstype
== unknown_type_node
)
7967 if (complain
& tf_error
)
7968 error ("not enough type information");
7969 return error_mark_node
;
7972 if (TREE_TYPE (rhs
) != NULL_TREE
&& ! (type_unknown_p (rhs
)))
7974 tree fntype
= non_reference (lhstype
);
7975 if (same_type_p (fntype
, TREE_TYPE (rhs
)))
7977 if (fnptr_conv_p (fntype
, TREE_TYPE (rhs
)))
7979 if (flag_ms_extensions
7980 && TYPE_PTRMEMFUNC_P (fntype
)
7981 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs
)))
7982 /* Microsoft allows `A::f' to be resolved to a
7983 pointer-to-member. */
7987 if (complain
& tf_error
)
7988 error ("cannot convert %qE from type %qT to type %qT",
7989 rhs
, TREE_TYPE (rhs
), fntype
);
7990 return error_mark_node
;
7994 if (BASELINK_P (rhs
))
7996 access_path
= BASELINK_ACCESS_BINFO (rhs
);
7997 rhs
= BASELINK_FUNCTIONS (rhs
);
8000 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
8001 deduce any type information. */
8002 if (TREE_CODE (rhs
) == NON_DEPENDENT_EXPR
)
8004 if (complain
& tf_error
)
8005 error ("not enough type information");
8006 return error_mark_node
;
8009 /* If we instantiate a template, and it is a A ?: C expression
8010 with omitted B, look through the SAVE_EXPR. */
8011 if (TREE_CODE (rhs
) == SAVE_EXPR
)
8012 rhs
= TREE_OPERAND (rhs
, 0);
8014 /* There are only a few kinds of expressions that may have a type
8015 dependent on overload resolution. */
8016 gcc_assert (TREE_CODE (rhs
) == ADDR_EXPR
8017 || TREE_CODE (rhs
) == COMPONENT_REF
8018 || is_overloaded_fn (rhs
)
8019 || (flag_ms_extensions
&& TREE_CODE (rhs
) == FUNCTION_DECL
));
8021 /* This should really only be used when attempting to distinguish
8022 what sort of a pointer to function we have. For now, any
8023 arithmetic operation which is not supported on pointers
8024 is rejected as an error. */
8026 switch (TREE_CODE (rhs
))
8030 tree member
= TREE_OPERAND (rhs
, 1);
8032 member
= instantiate_type (lhstype
, member
, complain
);
8033 if (member
!= error_mark_node
8034 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs
, 0)))
8035 /* Do not lose object's side effects. */
8036 return build2 (COMPOUND_EXPR
, TREE_TYPE (member
),
8037 TREE_OPERAND (rhs
, 0), member
);
8042 rhs
= TREE_OPERAND (rhs
, 1);
8043 if (BASELINK_P (rhs
))
8044 return instantiate_type (lhstype
, rhs
, complain_in
);
8046 /* This can happen if we are forming a pointer-to-member for a
8048 gcc_assert (TREE_CODE (rhs
) == TEMPLATE_ID_EXPR
);
8052 case TEMPLATE_ID_EXPR
:
8054 tree fns
= TREE_OPERAND (rhs
, 0);
8055 tree args
= TREE_OPERAND (rhs
, 1);
8058 resolve_address_of_overloaded_function (lhstype
, fns
, complain_in
,
8059 /*template_only=*/true,
8066 resolve_address_of_overloaded_function (lhstype
, rhs
, complain_in
,
8067 /*template_only=*/false,
8068 /*explicit_targs=*/NULL_TREE
,
8073 if (PTRMEM_OK_P (rhs
))
8074 complain
|= tf_ptrmem_ok
;
8076 return instantiate_type (lhstype
, TREE_OPERAND (rhs
, 0), complain
);
8080 return error_mark_node
;
8085 return error_mark_node
;
8088 /* Return the name of the virtual function pointer field
8089 (as an IDENTIFIER_NODE) for the given TYPE. Note that
8090 this may have to look back through base types to find the
8091 ultimate field name. (For single inheritance, these could
8092 all be the same name. Who knows for multiple inheritance). */
8095 get_vfield_name (tree type
)
8097 tree binfo
, base_binfo
;
8099 for (binfo
= TYPE_BINFO (type
);
8100 BINFO_N_BASE_BINFOS (binfo
);
8103 base_binfo
= BINFO_BASE_BINFO (binfo
, 0);
8105 if (BINFO_VIRTUAL_P (base_binfo
)
8106 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo
)))
8110 type
= BINFO_TYPE (binfo
);
8111 tree ctor_name
= constructor_name (type
);
8112 char *buf
= (char *) alloca (sizeof (VFIELD_NAME_FORMAT
)
8113 + IDENTIFIER_LENGTH (ctor_name
) + 2);
8114 sprintf (buf
, VFIELD_NAME_FORMAT
, IDENTIFIER_POINTER (ctor_name
));
8115 return get_identifier (buf
);
8119 print_class_statistics (void)
8121 if (! GATHER_STATISTICS
)
8124 fprintf (stderr
, "convert_harshness = %d\n", n_convert_harshness
);
8125 fprintf (stderr
, "compute_conversion_costs = %d\n", n_compute_conversion_costs
);
8128 fprintf (stderr
, "vtables = %d; vtable searches = %d\n",
8129 n_vtables
, n_vtable_searches
);
8130 fprintf (stderr
, "vtable entries = %d; vtable elems = %d\n",
8131 n_vtable_entries
, n_vtable_elems
);
8135 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
8136 according to [class]:
8137 The class-name is also inserted
8138 into the scope of the class itself. For purposes of access checking,
8139 the inserted class name is treated as if it were a public member name. */
8142 build_self_reference (void)
8144 tree name
= DECL_NAME (TYPE_NAME (current_class_type
));
8145 tree value
= build_lang_decl (TYPE_DECL
, name
, current_class_type
);
8147 DECL_NONLOCAL (value
) = 1;
8148 DECL_CONTEXT (value
) = current_class_type
;
8149 DECL_ARTIFICIAL (value
) = 1;
8150 SET_DECL_SELF_REFERENCE_P (value
);
8151 set_underlying_type (value
);
8153 if (processing_template_decl
)
8154 value
= push_template_decl (value
);
8156 tree saved_cas
= current_access_specifier
;
8157 current_access_specifier
= access_public_node
;
8158 finish_member_declaration (value
);
8159 current_access_specifier
= saved_cas
;
8162 /* Returns 1 if TYPE contains only padding bytes. */
8165 is_empty_class (tree type
)
8167 if (type
== error_mark_node
)
8170 if (! CLASS_TYPE_P (type
))
8173 return CLASSTYPE_EMPTY_P (type
);
8176 /* Returns true if TYPE contains no actual data, just various
8177 possible combinations of empty classes and possibly a vptr. */
8180 is_really_empty_class (tree type
)
8182 if (CLASS_TYPE_P (type
))
8189 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
8190 out, but we'd like to be able to check this before then. */
8191 if (COMPLETE_TYPE_P (type
) && is_empty_class (type
))
8194 for (binfo
= TYPE_BINFO (type
), i
= 0;
8195 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); ++i
)
8196 if (!is_really_empty_class (BINFO_TYPE (base_binfo
)))
8198 for (field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
8199 if (TREE_CODE (field
) == FIELD_DECL
8200 && !DECL_ARTIFICIAL (field
)
8201 /* An unnamed bit-field is not a data member. */
8202 && (DECL_NAME (field
) || !DECL_C_BIT_FIELD (field
))
8203 && !is_really_empty_class (TREE_TYPE (field
)))
8207 else if (TREE_CODE (type
) == ARRAY_TYPE
)
8208 return (integer_zerop (array_type_nelts_top (type
))
8209 || is_really_empty_class (TREE_TYPE (type
)));
8213 /* Note that NAME was looked up while the current class was being
8214 defined and that the result of that lookup was DECL. */
8217 maybe_note_name_used_in_class (tree name
, tree decl
)
8219 splay_tree names_used
;
8221 /* If we're not defining a class, there's nothing to do. */
8222 if (!(innermost_scope_kind() == sk_class
8223 && TYPE_BEING_DEFINED (current_class_type
)
8224 && !LAMBDA_TYPE_P (current_class_type
)))
8227 /* If there's already a binding for this NAME, then we don't have
8228 anything to worry about. */
8229 if (lookup_member (current_class_type
, name
,
8230 /*protect=*/0, /*want_type=*/false, tf_warning_or_error
))
8233 if (!current_class_stack
[current_class_depth
- 1].names_used
)
8234 current_class_stack
[current_class_depth
- 1].names_used
8235 = splay_tree_new (splay_tree_compare_pointers
, 0, 0);
8236 names_used
= current_class_stack
[current_class_depth
- 1].names_used
;
8238 splay_tree_insert (names_used
,
8239 (splay_tree_key
) name
,
8240 (splay_tree_value
) decl
);
8243 /* Note that NAME was declared (as DECL) in the current class. Check
8244 to see that the declaration is valid. */
8247 note_name_declared_in_class (tree name
, tree decl
)
8249 splay_tree names_used
;
8252 /* Look to see if we ever used this name. */
8254 = current_class_stack
[current_class_depth
- 1].names_used
;
8257 /* The C language allows members to be declared with a type of the same
8258 name, and the C++ standard says this diagnostic is not required. So
8259 allow it in extern "C" blocks unless predantic is specified.
8260 Allow it in all cases if -ms-extensions is specified. */
8261 if ((!pedantic
&& current_lang_name
== lang_name_c
)
8262 || flag_ms_extensions
)
8264 n
= splay_tree_lookup (names_used
, (splay_tree_key
) name
);
8267 /* [basic.scope.class]
8269 A name N used in a class S shall refer to the same declaration
8270 in its context and when re-evaluated in the completed scope of
8272 permerror (input_location
, "declaration of %q#D", decl
);
8273 permerror (location_of ((tree
) n
->value
),
8274 "changes meaning of %qD from %q#D",
8275 OVL_NAME (decl
), (tree
) n
->value
);
8279 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
8280 Secondary vtables are merged with primary vtables; this function
8281 will return the VAR_DECL for the primary vtable. */
8284 get_vtbl_decl_for_binfo (tree binfo
)
8288 decl
= BINFO_VTABLE (binfo
);
8289 if (decl
&& TREE_CODE (decl
) == POINTER_PLUS_EXPR
)
8291 gcc_assert (TREE_CODE (TREE_OPERAND (decl
, 0)) == ADDR_EXPR
);
8292 decl
= TREE_OPERAND (TREE_OPERAND (decl
, 0), 0);
8295 gcc_assert (VAR_P (decl
));
8300 /* Returns the binfo for the primary base of BINFO. If the resulting
8301 BINFO is a virtual base, and it is inherited elsewhere in the
8302 hierarchy, then the returned binfo might not be the primary base of
8303 BINFO in the complete object. Check BINFO_PRIMARY_P or
8304 BINFO_LOST_PRIMARY_P to be sure. */
8307 get_primary_binfo (tree binfo
)
8311 primary_base
= CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo
));
8315 return copied_binfo (primary_base
, binfo
);
8318 /* As above, but iterate until we reach the binfo that actually provides the
8322 most_primary_binfo (tree binfo
)
8325 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b
))
8326 && !BINFO_LOST_PRIMARY_P (b
))
8328 tree primary_base
= get_primary_binfo (b
);
8329 gcc_assert (BINFO_PRIMARY_P (primary_base
)
8330 && BINFO_INHERITANCE_CHAIN (primary_base
) == b
);
8336 /* Returns true if BINFO gets its vptr from a virtual base of the most derived
8337 type. Note that the virtual inheritance might be above or below BINFO in
8341 vptr_via_virtual_p (tree binfo
)
8344 binfo
= TYPE_BINFO (binfo
);
8345 tree primary
= most_primary_binfo (binfo
);
8346 /* Don't limit binfo_via_virtual, we want to return true when BINFO itself is
8347 a morally virtual base. */
8348 tree virt
= binfo_via_virtual (primary
, NULL_TREE
);
8349 return virt
!= NULL_TREE
;
8352 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
8355 maybe_indent_hierarchy (FILE * stream
, int indent
, int indented_p
)
8358 fprintf (stream
, "%*s", indent
, "");
8362 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
8363 INDENT should be zero when called from the top level; it is
8364 incremented recursively. IGO indicates the next expected BINFO in
8365 inheritance graph ordering. */
8368 dump_class_hierarchy_r (FILE *stream
,
8378 indented
= maybe_indent_hierarchy (stream
, indent
, 0);
8379 fprintf (stream
, "%s (0x" HOST_WIDE_INT_PRINT_HEX
") ",
8380 type_as_string (BINFO_TYPE (binfo
), TFF_PLAIN_IDENTIFIER
),
8381 (HOST_WIDE_INT
) (uintptr_t) binfo
);
8384 fprintf (stream
, "alternative-path\n");
8387 igo
= TREE_CHAIN (binfo
);
8389 fprintf (stream
, HOST_WIDE_INT_PRINT_DEC
,
8390 tree_to_shwi (BINFO_OFFSET (binfo
)));
8391 if (is_empty_class (BINFO_TYPE (binfo
)))
8392 fprintf (stream
, " empty");
8393 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo
)))
8394 fprintf (stream
, " nearly-empty");
8395 if (BINFO_VIRTUAL_P (binfo
))
8396 fprintf (stream
, " virtual");
8397 fprintf (stream
, "\n");
8400 if (BINFO_PRIMARY_P (binfo
))
8402 indented
= maybe_indent_hierarchy (stream
, indent
+ 3, indented
);
8403 fprintf (stream
, " primary-for %s (0x" HOST_WIDE_INT_PRINT_HEX
")",
8404 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo
)),
8405 TFF_PLAIN_IDENTIFIER
),
8406 (HOST_WIDE_INT
) (uintptr_t) BINFO_INHERITANCE_CHAIN (binfo
));
8408 if (BINFO_LOST_PRIMARY_P (binfo
))
8410 indented
= maybe_indent_hierarchy (stream
, indent
+ 3, indented
);
8411 fprintf (stream
, " lost-primary");
8414 fprintf (stream
, "\n");
8416 if (!(flags
& TDF_SLIM
))
8420 if (BINFO_SUBVTT_INDEX (binfo
))
8422 indented
= maybe_indent_hierarchy (stream
, indent
+ 3, indented
);
8423 fprintf (stream
, " subvttidx=%s",
8424 expr_as_string (BINFO_SUBVTT_INDEX (binfo
),
8425 TFF_PLAIN_IDENTIFIER
));
8427 if (BINFO_VPTR_INDEX (binfo
))
8429 indented
= maybe_indent_hierarchy (stream
, indent
+ 3, indented
);
8430 fprintf (stream
, " vptridx=%s",
8431 expr_as_string (BINFO_VPTR_INDEX (binfo
),
8432 TFF_PLAIN_IDENTIFIER
));
8434 if (BINFO_VPTR_FIELD (binfo
))
8436 indented
= maybe_indent_hierarchy (stream
, indent
+ 3, indented
);
8437 fprintf (stream
, " vbaseoffset=%s",
8438 expr_as_string (BINFO_VPTR_FIELD (binfo
),
8439 TFF_PLAIN_IDENTIFIER
));
8441 if (BINFO_VTABLE (binfo
))
8443 indented
= maybe_indent_hierarchy (stream
, indent
+ 3, indented
);
8444 fprintf (stream
, " vptr=%s",
8445 expr_as_string (BINFO_VTABLE (binfo
),
8446 TFF_PLAIN_IDENTIFIER
));
8450 fprintf (stream
, "\n");
8453 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
8454 igo
= dump_class_hierarchy_r (stream
, flags
, base_binfo
, igo
, indent
+ 2);
8459 /* Dump the BINFO hierarchy for T. */
8462 dump_class_hierarchy_1 (FILE *stream
, dump_flags_t flags
, tree t
)
8464 fprintf (stream
, "Class %s\n", type_as_string (t
, TFF_PLAIN_IDENTIFIER
));
8465 fprintf (stream
, " size=%lu align=%lu\n",
8466 (unsigned long)(tree_to_shwi (TYPE_SIZE (t
)) / BITS_PER_UNIT
),
8467 (unsigned long)(TYPE_ALIGN (t
) / BITS_PER_UNIT
));
8468 fprintf (stream
, " base size=%lu base align=%lu\n",
8469 (unsigned long)(tree_to_shwi (TYPE_SIZE (CLASSTYPE_AS_BASE (t
)))
8471 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t
))
8473 dump_class_hierarchy_r (stream
, flags
, TYPE_BINFO (t
), TYPE_BINFO (t
), 0);
8474 fprintf (stream
, "\n");
8477 /* Debug interface to hierarchy dumping. */
8480 debug_class (tree t
)
8482 dump_class_hierarchy_1 (stderr
, TDF_SLIM
, t
);
8486 dump_class_hierarchy (tree t
)
8489 if (FILE *stream
= dump_begin (class_dump_id
, &flags
))
8491 dump_class_hierarchy_1 (stream
, flags
, t
);
8492 dump_end (class_dump_id
, stream
);
8497 dump_array (FILE * stream
, tree decl
)
8500 unsigned HOST_WIDE_INT ix
;
8502 tree size
= TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl
)));
8504 elt
= (tree_to_shwi (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl
))))
8506 fprintf (stream
, "%s:", decl_as_string (decl
, TFF_PLAIN_IDENTIFIER
));
8507 fprintf (stream
, " %s entries",
8508 expr_as_string (size_binop (PLUS_EXPR
, size
, size_one_node
),
8509 TFF_PLAIN_IDENTIFIER
));
8510 fprintf (stream
, "\n");
8512 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl
)),
8514 fprintf (stream
, "%-4ld %s\n", (long)(ix
* elt
),
8515 expr_as_string (value
, TFF_PLAIN_IDENTIFIER
));
8519 dump_vtable (tree t
, tree binfo
, tree vtable
)
8522 FILE *stream
= dump_begin (class_dump_id
, &flags
);
8527 if (!(flags
& TDF_SLIM
))
8529 int ctor_vtbl_p
= TYPE_BINFO (t
) != binfo
;
8531 fprintf (stream
, "%s for %s",
8532 ctor_vtbl_p
? "Construction vtable" : "Vtable",
8533 type_as_string (BINFO_TYPE (binfo
), TFF_PLAIN_IDENTIFIER
));
8536 if (!BINFO_VIRTUAL_P (binfo
))
8537 fprintf (stream
, " (0x" HOST_WIDE_INT_PRINT_HEX
" instance)",
8538 (HOST_WIDE_INT
) (uintptr_t) binfo
);
8539 fprintf (stream
, " in %s", type_as_string (t
, TFF_PLAIN_IDENTIFIER
));
8541 fprintf (stream
, "\n");
8542 dump_array (stream
, vtable
);
8543 fprintf (stream
, "\n");
8546 dump_end (class_dump_id
, stream
);
8550 dump_vtt (tree t
, tree vtt
)
8553 FILE *stream
= dump_begin (class_dump_id
, &flags
);
8558 if (!(flags
& TDF_SLIM
))
8560 fprintf (stream
, "VTT for %s\n",
8561 type_as_string (t
, TFF_PLAIN_IDENTIFIER
));
8562 dump_array (stream
, vtt
);
8563 fprintf (stream
, "\n");
8566 dump_end (class_dump_id
, stream
);
8569 /* Dump a function or thunk and its thunkees. */
8572 dump_thunk (FILE *stream
, int indent
, tree thunk
)
8574 static const char spaces
[] = " ";
8575 tree name
= DECL_NAME (thunk
);
8578 fprintf (stream
, "%.*s%p %s %s", indent
, spaces
,
8580 !DECL_THUNK_P (thunk
) ? "function"
8581 : DECL_THIS_THUNK_P (thunk
) ? "this-thunk" : "covariant-thunk",
8582 name
? IDENTIFIER_POINTER (name
) : "<unset>");
8583 if (DECL_THUNK_P (thunk
))
8585 HOST_WIDE_INT fixed_adjust
= THUNK_FIXED_OFFSET (thunk
);
8586 tree virtual_adjust
= THUNK_VIRTUAL_OFFSET (thunk
);
8588 fprintf (stream
, " fixed=" HOST_WIDE_INT_PRINT_DEC
, fixed_adjust
);
8589 if (!virtual_adjust
)
8591 else if (DECL_THIS_THUNK_P (thunk
))
8592 fprintf (stream
, " vcall=" HOST_WIDE_INT_PRINT_DEC
,
8593 tree_to_shwi (virtual_adjust
));
8595 fprintf (stream
, " vbase=" HOST_WIDE_INT_PRINT_DEC
"(%s)",
8596 tree_to_shwi (BINFO_VPTR_FIELD (virtual_adjust
)),
8597 type_as_string (BINFO_TYPE (virtual_adjust
), TFF_SCOPE
));
8598 if (THUNK_ALIAS (thunk
))
8599 fprintf (stream
, " alias to %p", (void *)THUNK_ALIAS (thunk
));
8601 fprintf (stream
, "\n");
8602 for (thunks
= DECL_THUNKS (thunk
); thunks
; thunks
= TREE_CHAIN (thunks
))
8603 dump_thunk (stream
, indent
+ 2, thunks
);
8606 /* Dump the thunks for FN. */
8609 debug_thunks (tree fn
)
8611 dump_thunk (stderr
, 0, fn
);
8614 /* Virtual function table initialization. */
8616 /* Create all the necessary vtables for T and its base classes. */
8619 finish_vtbls (tree t
)
8622 vec
<constructor_elt
, va_gc
> *v
= NULL
;
8623 tree vtable
= BINFO_VTABLE (TYPE_BINFO (t
));
8625 /* We lay out the primary and secondary vtables in one contiguous
8626 vtable. The primary vtable is first, followed by the non-virtual
8627 secondary vtables in inheritance graph order. */
8628 accumulate_vtbl_inits (TYPE_BINFO (t
), TYPE_BINFO (t
), TYPE_BINFO (t
),
8631 /* Then come the virtual bases, also in inheritance graph order. */
8632 for (vbase
= TYPE_BINFO (t
); vbase
; vbase
= TREE_CHAIN (vbase
))
8634 if (!BINFO_VIRTUAL_P (vbase
))
8636 accumulate_vtbl_inits (vbase
, vbase
, TYPE_BINFO (t
), vtable
, t
, &v
);
8639 if (BINFO_VTABLE (TYPE_BINFO (t
)))
8640 initialize_vtable (TYPE_BINFO (t
), v
);
8643 /* Initialize the vtable for BINFO with the INITS. */
8646 initialize_vtable (tree binfo
, vec
<constructor_elt
, va_gc
> *inits
)
8650 layout_vtable_decl (binfo
, vec_safe_length (inits
));
8651 decl
= get_vtbl_decl_for_binfo (binfo
);
8652 initialize_artificial_var (decl
, inits
);
8653 dump_vtable (BINFO_TYPE (binfo
), binfo
, decl
);
8656 /* Build the VTT (virtual table table) for T.
8657 A class requires a VTT if it has virtual bases.
8660 1 - primary virtual pointer for complete object T
8661 2 - secondary VTTs for each direct non-virtual base of T which requires a
8663 3 - secondary virtual pointers for each direct or indirect base of T which
8664 has virtual bases or is reachable via a virtual path from T.
8665 4 - secondary VTTs for each direct or indirect virtual base of T.
8667 Secondary VTTs look like complete object VTTs without part 4. */
8675 vec
<constructor_elt
, va_gc
> *inits
;
8677 /* Build up the initializers for the VTT. */
8679 index
= size_zero_node
;
8680 build_vtt_inits (TYPE_BINFO (t
), t
, &inits
, &index
);
8682 /* If we didn't need a VTT, we're done. */
8686 /* Figure out the type of the VTT. */
8687 type
= build_array_of_n_type (const_ptr_type_node
,
8690 /* Now, build the VTT object itself. */
8691 vtt
= build_vtable (t
, mangle_vtt_for_type (t
), type
);
8692 initialize_artificial_var (vtt
, inits
);
8693 /* Add the VTT to the vtables list. */
8694 DECL_CHAIN (vtt
) = DECL_CHAIN (CLASSTYPE_VTABLES (t
));
8695 DECL_CHAIN (CLASSTYPE_VTABLES (t
)) = vtt
;
8700 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
8701 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
8702 and CHAIN the vtable pointer for this binfo after construction is
8703 complete. VALUE can also be another BINFO, in which case we recurse. */
8706 binfo_ctor_vtable (tree binfo
)
8712 vt
= BINFO_VTABLE (binfo
);
8713 if (TREE_CODE (vt
) == TREE_LIST
)
8714 vt
= TREE_VALUE (vt
);
8715 if (TREE_CODE (vt
) == TREE_BINFO
)
8724 /* Data for secondary VTT initialization. */
8725 struct secondary_vptr_vtt_init_data
8727 /* Is this the primary VTT? */
8730 /* Current index into the VTT. */
8733 /* Vector of initializers built up. */
8734 vec
<constructor_elt
, va_gc
> *inits
;
8736 /* The type being constructed by this secondary VTT. */
8737 tree type_being_constructed
;
8740 /* Recursively build the VTT-initializer for BINFO (which is in the
8741 hierarchy dominated by T). INITS points to the end of the initializer
8742 list to date. INDEX is the VTT index where the next element will be
8743 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
8744 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
8745 for virtual bases of T. When it is not so, we build the constructor
8746 vtables for the BINFO-in-T variant. */
8749 build_vtt_inits (tree binfo
, tree t
, vec
<constructor_elt
, va_gc
> **inits
,
8755 secondary_vptr_vtt_init_data data
;
8756 int top_level_p
= SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), t
);
8758 /* We only need VTTs for subobjects with virtual bases. */
8759 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo
)))
8762 /* We need to use a construction vtable if this is not the primary
8766 build_ctor_vtbl_group (binfo
, t
);
8768 /* Record the offset in the VTT where this sub-VTT can be found. */
8769 BINFO_SUBVTT_INDEX (binfo
) = *index
;
8772 /* Add the address of the primary vtable for the complete object. */
8773 init
= binfo_ctor_vtable (binfo
);
8774 CONSTRUCTOR_APPEND_ELT (*inits
, NULL_TREE
, init
);
8777 gcc_assert (!BINFO_VPTR_INDEX (binfo
));
8778 BINFO_VPTR_INDEX (binfo
) = *index
;
8780 *index
= size_binop (PLUS_EXPR
, *index
, TYPE_SIZE_UNIT (ptr_type_node
));
8782 /* Recursively add the secondary VTTs for non-virtual bases. */
8783 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, b
); ++i
)
8784 if (!BINFO_VIRTUAL_P (b
))
8785 build_vtt_inits (b
, t
, inits
, index
);
8787 /* Add secondary virtual pointers for all subobjects of BINFO with
8788 either virtual bases or reachable along a virtual path, except
8789 subobjects that are non-virtual primary bases. */
8790 data
.top_level_p
= top_level_p
;
8791 data
.index
= *index
;
8792 data
.inits
= *inits
;
8793 data
.type_being_constructed
= BINFO_TYPE (binfo
);
8795 dfs_walk_once (binfo
, dfs_build_secondary_vptr_vtt_inits
, NULL
, &data
);
8797 *index
= data
.index
;
8799 /* data.inits might have grown as we added secondary virtual pointers.
8800 Make sure our caller knows about the new vector. */
8801 *inits
= data
.inits
;
8804 /* Add the secondary VTTs for virtual bases in inheritance graph
8806 for (b
= TYPE_BINFO (BINFO_TYPE (binfo
)); b
; b
= TREE_CHAIN (b
))
8808 if (!BINFO_VIRTUAL_P (b
))
8811 build_vtt_inits (b
, t
, inits
, index
);
8814 /* Remove the ctor vtables we created. */
8815 dfs_walk_all (binfo
, dfs_fixup_binfo_vtbls
, NULL
, binfo
);
8818 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
8819 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
8822 dfs_build_secondary_vptr_vtt_inits (tree binfo
, void *data_
)
8824 secondary_vptr_vtt_init_data
*data
= (secondary_vptr_vtt_init_data
*)data_
;
8826 /* We don't care about bases that don't have vtables. */
8827 if (!TYPE_VFIELD (BINFO_TYPE (binfo
)))
8828 return dfs_skip_bases
;
8830 /* We're only interested in proper subobjects of the type being
8832 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), data
->type_being_constructed
))
8835 /* We're only interested in bases with virtual bases or reachable
8836 via a virtual path from the type being constructed. */
8837 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo
))
8838 || binfo_via_virtual (binfo
, data
->type_being_constructed
)))
8839 return dfs_skip_bases
;
8841 /* We're not interested in non-virtual primary bases. */
8842 if (!BINFO_VIRTUAL_P (binfo
) && BINFO_PRIMARY_P (binfo
))
8845 /* Record the index where this secondary vptr can be found. */
8846 if (data
->top_level_p
)
8848 gcc_assert (!BINFO_VPTR_INDEX (binfo
));
8849 BINFO_VPTR_INDEX (binfo
) = data
->index
;
8851 if (BINFO_VIRTUAL_P (binfo
))
8853 /* It's a primary virtual base, and this is not a
8854 construction vtable. Find the base this is primary of in
8855 the inheritance graph, and use that base's vtable
8857 while (BINFO_PRIMARY_P (binfo
))
8858 binfo
= BINFO_INHERITANCE_CHAIN (binfo
);
8862 /* Add the initializer for the secondary vptr itself. */
8863 CONSTRUCTOR_APPEND_ELT (data
->inits
, NULL_TREE
, binfo_ctor_vtable (binfo
));
8865 /* Advance the vtt index. */
8866 data
->index
= size_binop (PLUS_EXPR
, data
->index
,
8867 TYPE_SIZE_UNIT (ptr_type_node
));
8872 /* Called from build_vtt_inits via dfs_walk. After building
8873 constructor vtables and generating the sub-vtt from them, we need
8874 to restore the BINFO_VTABLES that were scribbled on. DATA is the
8875 binfo of the base whose sub vtt was generated. */
8878 dfs_fixup_binfo_vtbls (tree binfo
, void* data
)
8880 tree vtable
= BINFO_VTABLE (binfo
);
8882 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo
)))
8883 /* If this class has no vtable, none of its bases do. */
8884 return dfs_skip_bases
;
8887 /* This might be a primary base, so have no vtable in this
8891 /* If we scribbled the construction vtable vptr into BINFO, clear it
8893 if (TREE_CODE (vtable
) == TREE_LIST
8894 && (TREE_PURPOSE (vtable
) == (tree
) data
))
8895 BINFO_VTABLE (binfo
) = TREE_CHAIN (vtable
);
8900 /* Build the construction vtable group for BINFO which is in the
8901 hierarchy dominated by T. */
8904 build_ctor_vtbl_group (tree binfo
, tree t
)
8910 vec
<constructor_elt
, va_gc
> *v
;
8912 /* See if we've already created this construction vtable group. */
8913 id
= mangle_ctor_vtbl_for_type (t
, binfo
);
8914 if (IDENTIFIER_GLOBAL_VALUE (id
))
8917 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), t
));
8918 /* Build a version of VTBL (with the wrong type) for use in
8919 constructing the addresses of secondary vtables in the
8920 construction vtable group. */
8921 vtbl
= build_vtable (t
, id
, ptr_type_node
);
8922 DECL_CONSTRUCTION_VTABLE_P (vtbl
) = 1;
8923 /* Don't export construction vtables from shared libraries. Even on
8924 targets that don't support hidden visibility, this tells
8925 can_refer_decl_in_current_unit_p not to assume that it's safe to
8926 access from a different compilation unit (bz 54314). */
8927 DECL_VISIBILITY (vtbl
) = VISIBILITY_HIDDEN
;
8928 DECL_VISIBILITY_SPECIFIED (vtbl
) = true;
8931 accumulate_vtbl_inits (binfo
, TYPE_BINFO (TREE_TYPE (binfo
)),
8932 binfo
, vtbl
, t
, &v
);
8934 /* Add the vtables for each of our virtual bases using the vbase in T
8936 for (vbase
= TYPE_BINFO (BINFO_TYPE (binfo
));
8938 vbase
= TREE_CHAIN (vbase
))
8942 if (!BINFO_VIRTUAL_P (vbase
))
8944 b
= copied_binfo (vbase
, binfo
);
8946 accumulate_vtbl_inits (b
, vbase
, binfo
, vtbl
, t
, &v
);
8949 /* Figure out the type of the construction vtable. */
8950 type
= build_array_of_n_type (vtable_entry_type
, v
->length ());
8952 TREE_TYPE (vtbl
) = type
;
8953 DECL_SIZE (vtbl
) = DECL_SIZE_UNIT (vtbl
) = NULL_TREE
;
8954 layout_decl (vtbl
, 0);
8956 /* Initialize the construction vtable. */
8957 CLASSTYPE_VTABLES (t
) = chainon (CLASSTYPE_VTABLES (t
), vtbl
);
8958 initialize_artificial_var (vtbl
, v
);
8959 dump_vtable (t
, binfo
, vtbl
);
8962 /* Add the vtbl initializers for BINFO (and its bases other than
8963 non-virtual primaries) to the list of INITS. BINFO is in the
8964 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
8965 the constructor the vtbl inits should be accumulated for. (If this
8966 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
8967 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
8968 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
8969 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
8970 but are not necessarily the same in terms of layout. */
8973 accumulate_vtbl_inits (tree binfo
,
8978 vec
<constructor_elt
, va_gc
> **inits
)
8982 int ctor_vtbl_p
= !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo
), t
);
8984 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), BINFO_TYPE (orig_binfo
)));
8986 /* If it doesn't have a vptr, we don't do anything. */
8987 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo
)))
8990 /* If we're building a construction vtable, we're not interested in
8991 subobjects that don't require construction vtables. */
8993 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo
))
8994 && !binfo_via_virtual (orig_binfo
, BINFO_TYPE (rtti_binfo
)))
8997 /* Build the initializers for the BINFO-in-T vtable. */
8998 dfs_accumulate_vtbl_inits (binfo
, orig_binfo
, rtti_binfo
, vtbl
, t
, inits
);
9000 /* Walk the BINFO and its bases. We walk in preorder so that as we
9001 initialize each vtable we can figure out at what offset the
9002 secondary vtable lies from the primary vtable. We can't use
9003 dfs_walk here because we need to iterate through bases of BINFO
9004 and RTTI_BINFO simultaneously. */
9005 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); ++i
)
9007 /* Skip virtual bases. */
9008 if (BINFO_VIRTUAL_P (base_binfo
))
9010 accumulate_vtbl_inits (base_binfo
,
9011 BINFO_BASE_BINFO (orig_binfo
, i
),
9012 rtti_binfo
, vtbl
, t
,
9017 /* Called from accumulate_vtbl_inits. Adds the initializers for the
9018 BINFO vtable to L. */
9021 dfs_accumulate_vtbl_inits (tree binfo
,
9026 vec
<constructor_elt
, va_gc
> **l
)
9028 tree vtbl
= NULL_TREE
;
9029 int ctor_vtbl_p
= !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo
), t
);
9033 && BINFO_VIRTUAL_P (orig_binfo
) && BINFO_PRIMARY_P (orig_binfo
))
9035 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
9036 primary virtual base. If it is not the same primary in
9037 the hierarchy of T, we'll need to generate a ctor vtable
9038 for it, to place at its location in T. If it is the same
9039 primary, we still need a VTT entry for the vtable, but it
9040 should point to the ctor vtable for the base it is a
9041 primary for within the sub-hierarchy of RTTI_BINFO.
9043 There are three possible cases:
9045 1) We are in the same place.
9046 2) We are a primary base within a lost primary virtual base of
9048 3) We are primary to something not a base of RTTI_BINFO. */
9051 tree last
= NULL_TREE
;
9053 /* First, look through the bases we are primary to for RTTI_BINFO
9054 or a virtual base. */
9056 while (BINFO_PRIMARY_P (b
))
9058 b
= BINFO_INHERITANCE_CHAIN (b
);
9060 if (BINFO_VIRTUAL_P (b
) || b
== rtti_binfo
)
9063 /* If we run out of primary links, keep looking down our
9064 inheritance chain; we might be an indirect primary. */
9065 for (b
= last
; b
; b
= BINFO_INHERITANCE_CHAIN (b
))
9066 if (BINFO_VIRTUAL_P (b
) || b
== rtti_binfo
)
9070 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
9071 base B and it is a base of RTTI_BINFO, this is case 2. In
9072 either case, we share our vtable with LAST, i.e. the
9073 derived-most base within B of which we are a primary. */
9075 || (b
&& binfo_for_vbase (BINFO_TYPE (b
), BINFO_TYPE (rtti_binfo
))))
9076 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
9077 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
9078 binfo_ctor_vtable after everything's been set up. */
9081 /* Otherwise, this is case 3 and we get our own. */
9083 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo
))
9086 n_inits
= vec_safe_length (*l
);
9093 /* Add the initializer for this vtable. */
9094 build_vtbl_initializer (binfo
, orig_binfo
, t
, rtti_binfo
,
9095 &non_fn_entries
, l
);
9097 /* Figure out the position to which the VPTR should point. */
9098 vtbl
= build1 (ADDR_EXPR
, vtbl_ptr_type_node
, orig_vtbl
);
9099 index
= size_binop (MULT_EXPR
,
9100 TYPE_SIZE_UNIT (vtable_entry_type
),
9101 size_int (non_fn_entries
+ n_inits
));
9102 vtbl
= fold_build_pointer_plus (vtbl
, index
);
9106 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
9107 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
9108 straighten this out. */
9109 BINFO_VTABLE (binfo
) = tree_cons (rtti_binfo
, vtbl
, BINFO_VTABLE (binfo
));
9110 else if (BINFO_PRIMARY_P (binfo
) && BINFO_VIRTUAL_P (binfo
))
9111 /* Throw away any unneeded intializers. */
9112 (*l
)->truncate (n_inits
);
9114 /* For an ordinary vtable, set BINFO_VTABLE. */
9115 BINFO_VTABLE (binfo
) = vtbl
;
9118 static GTY(()) tree abort_fndecl_addr
;
9119 static GTY(()) tree dvirt_fn
;
9121 /* Construct the initializer for BINFO's virtual function table. BINFO
9122 is part of the hierarchy dominated by T. If we're building a
9123 construction vtable, the ORIG_BINFO is the binfo we should use to
9124 find the actual function pointers to put in the vtable - but they
9125 can be overridden on the path to most-derived in the graph that
9126 ORIG_BINFO belongs. Otherwise,
9127 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
9128 BINFO that should be indicated by the RTTI information in the
9129 vtable; it will be a base class of T, rather than T itself, if we
9130 are building a construction vtable.
9132 The value returned is a TREE_LIST suitable for wrapping in a
9133 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
9134 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
9135 number of non-function entries in the vtable.
9137 It might seem that this function should never be called with a
9138 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
9139 base is always subsumed by a derived class vtable. However, when
9140 we are building construction vtables, we do build vtables for
9141 primary bases; we need these while the primary base is being
9145 build_vtbl_initializer (tree binfo
,
9149 int* non_fn_entries_p
,
9150 vec
<constructor_elt
, va_gc
> **inits
)
9156 vec
<tree
, va_gc
> *vbases
;
9159 /* Initialize VID. */
9160 memset (&vid
, 0, sizeof (vid
));
9163 vid
.rtti_binfo
= rtti_binfo
;
9164 vid
.primary_vtbl_p
= SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), t
);
9165 vid
.ctor_vtbl_p
= !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo
), t
);
9166 vid
.generate_vcall_entries
= true;
9167 /* The first vbase or vcall offset is at index -3 in the vtable. */
9168 vid
.index
= ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE
);
9170 /* Add entries to the vtable for RTTI. */
9171 build_rtti_vtbl_entries (binfo
, &vid
);
9173 /* Create an array for keeping track of the functions we've
9174 processed. When we see multiple functions with the same
9175 signature, we share the vcall offsets. */
9176 vec_alloc (vid
.fns
, 32);
9177 /* Add the vcall and vbase offset entries. */
9178 build_vcall_and_vbase_vtbl_entries (binfo
, &vid
);
9180 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
9181 build_vbase_offset_vtbl_entries. */
9182 for (vbases
= CLASSTYPE_VBASECLASSES (t
), ix
= 0;
9183 vec_safe_iterate (vbases
, ix
, &vbinfo
); ix
++)
9184 BINFO_VTABLE_PATH_MARKED (vbinfo
) = 0;
9186 /* If the target requires padding between data entries, add that now. */
9187 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE
> 1)
9189 int n_entries
= vec_safe_length (vid
.inits
);
9191 vec_safe_grow (vid
.inits
, TARGET_VTABLE_DATA_ENTRY_DISTANCE
* n_entries
);
9193 /* Move data entries into their new positions and add padding
9194 after the new positions. Iterate backwards so we don't
9195 overwrite entries that we would need to process later. */
9196 for (ix
= n_entries
- 1;
9197 vid
.inits
->iterate (ix
, &e
);
9201 int new_position
= (TARGET_VTABLE_DATA_ENTRY_DISTANCE
* ix
9202 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE
- 1));
9204 (*vid
.inits
)[new_position
] = *e
;
9206 for (j
= 1; j
< TARGET_VTABLE_DATA_ENTRY_DISTANCE
; ++j
)
9208 constructor_elt
*f
= &(*vid
.inits
)[new_position
- j
];
9209 f
->index
= NULL_TREE
;
9210 f
->value
= build1 (NOP_EXPR
, vtable_entry_type
,
9216 if (non_fn_entries_p
)
9217 *non_fn_entries_p
= vec_safe_length (vid
.inits
);
9219 /* The initializers for virtual functions were built up in reverse
9220 order. Straighten them out and add them to the running list in one
9222 jx
= vec_safe_length (*inits
);
9223 vec_safe_grow (*inits
, jx
+ vid
.inits
->length ());
9225 for (ix
= vid
.inits
->length () - 1;
9226 vid
.inits
->iterate (ix
, &e
);
9230 /* Go through all the ordinary virtual functions, building up
9232 for (v
= BINFO_VIRTUALS (orig_binfo
); v
; v
= TREE_CHAIN (v
))
9236 tree fn
, fn_original
;
9237 tree init
= NULL_TREE
;
9241 if (DECL_THUNK_P (fn
))
9243 if (!DECL_NAME (fn
))
9245 if (THUNK_ALIAS (fn
))
9247 fn
= THUNK_ALIAS (fn
);
9250 fn_original
= THUNK_TARGET (fn
);
9253 /* If the only definition of this function signature along our
9254 primary base chain is from a lost primary, this vtable slot will
9255 never be used, so just zero it out. This is important to avoid
9256 requiring extra thunks which cannot be generated with the function.
9258 We first check this in update_vtable_entry_for_fn, so we handle
9259 restored primary bases properly; we also need to do it here so we
9260 zero out unused slots in ctor vtables, rather than filling them
9261 with erroneous values (though harmless, apart from relocation
9263 if (BV_LOST_PRIMARY (v
))
9264 init
= size_zero_node
;
9268 /* Pull the offset for `this', and the function to call, out of
9270 delta
= BV_DELTA (v
);
9271 vcall_index
= BV_VCALL_INDEX (v
);
9273 gcc_assert (TREE_CODE (delta
) == INTEGER_CST
);
9274 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
9276 /* You can't call an abstract virtual function; it's abstract.
9277 So, we replace these functions with __pure_virtual. */
9278 if (DECL_PURE_VIRTUAL_P (fn_original
))
9281 if (!TARGET_VTABLE_USES_DESCRIPTORS
)
9283 if (abort_fndecl_addr
== NULL
)
9285 = fold_convert (vfunc_ptr_type_node
,
9286 build_fold_addr_expr (fn
));
9287 init
= abort_fndecl_addr
;
9290 /* Likewise for deleted virtuals. */
9291 else if (DECL_DELETED_FN (fn_original
))
9295 tree name
= get_identifier ("__cxa_deleted_virtual");
9296 dvirt_fn
= IDENTIFIER_GLOBAL_VALUE (name
);
9298 dvirt_fn
= push_library_fn
9300 build_function_type_list (void_type_node
, NULL_TREE
),
9301 NULL_TREE
, ECF_NORETURN
| ECF_COLD
);
9304 if (!TARGET_VTABLE_USES_DESCRIPTORS
)
9305 init
= fold_convert (vfunc_ptr_type_node
,
9306 build_fold_addr_expr (fn
));
9310 if (!integer_zerop (delta
) || vcall_index
)
9312 fn
= make_thunk (fn
, /*this_adjusting=*/1,
9313 delta
, vcall_index
);
9314 if (!DECL_NAME (fn
))
9317 /* Take the address of the function, considering it to be of an
9318 appropriate generic type. */
9319 if (!TARGET_VTABLE_USES_DESCRIPTORS
)
9320 init
= fold_convert (vfunc_ptr_type_node
,
9321 build_fold_addr_expr (fn
));
9322 /* Don't refer to a virtual destructor from a constructor
9323 vtable or a vtable for an abstract class, since destroying
9324 an object under construction is undefined behavior and we
9325 don't want it to be considered a candidate for speculative
9326 devirtualization. But do create the thunk for ABI
9328 if (DECL_DESTRUCTOR_P (fn_original
)
9329 && (CLASSTYPE_PURE_VIRTUALS (DECL_CONTEXT (fn_original
))
9330 || orig_binfo
!= binfo
))
9331 init
= size_zero_node
;
9335 /* And add it to the chain of initializers. */
9336 if (TARGET_VTABLE_USES_DESCRIPTORS
)
9339 if (init
== size_zero_node
)
9340 for (i
= 0; i
< TARGET_VTABLE_USES_DESCRIPTORS
; ++i
)
9341 CONSTRUCTOR_APPEND_ELT (*inits
, NULL_TREE
, init
);
9343 for (i
= 0; i
< TARGET_VTABLE_USES_DESCRIPTORS
; ++i
)
9345 tree fdesc
= build2 (FDESC_EXPR
, vfunc_ptr_type_node
,
9346 fn
, build_int_cst (NULL_TREE
, i
));
9347 TREE_CONSTANT (fdesc
) = 1;
9349 CONSTRUCTOR_APPEND_ELT (*inits
, NULL_TREE
, fdesc
);
9353 CONSTRUCTOR_APPEND_ELT (*inits
, NULL_TREE
, init
);
9357 /* Adds to vid->inits the initializers for the vbase and vcall
9358 offsets in BINFO, which is in the hierarchy dominated by T. */
9361 build_vcall_and_vbase_vtbl_entries (tree binfo
, vtbl_init_data
* vid
)
9365 /* If this is a derived class, we must first create entries
9366 corresponding to the primary base class. */
9367 b
= get_primary_binfo (binfo
);
9369 build_vcall_and_vbase_vtbl_entries (b
, vid
);
9371 /* Add the vbase entries for this base. */
9372 build_vbase_offset_vtbl_entries (binfo
, vid
);
9373 /* Add the vcall entries for this base. */
9374 build_vcall_offset_vtbl_entries (binfo
, vid
);
9377 /* Returns the initializers for the vbase offset entries in the vtable
9378 for BINFO (which is part of the class hierarchy dominated by T), in
9379 reverse order. VBASE_OFFSET_INDEX gives the vtable index
9380 where the next vbase offset will go. */
9383 build_vbase_offset_vtbl_entries (tree binfo
, vtbl_init_data
* vid
)
9387 tree non_primary_binfo
;
9389 /* If there are no virtual baseclasses, then there is nothing to
9391 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo
)))
9396 /* We might be a primary base class. Go up the inheritance hierarchy
9397 until we find the most derived class of which we are a primary base:
9398 it is the offset of that which we need to use. */
9399 non_primary_binfo
= binfo
;
9400 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo
))
9404 /* If we have reached a virtual base, then it must be a primary
9405 base (possibly multi-level) of vid->binfo, or we wouldn't
9406 have called build_vcall_and_vbase_vtbl_entries for it. But it
9407 might be a lost primary, so just skip down to vid->binfo. */
9408 if (BINFO_VIRTUAL_P (non_primary_binfo
))
9410 non_primary_binfo
= vid
->binfo
;
9414 b
= BINFO_INHERITANCE_CHAIN (non_primary_binfo
);
9415 if (get_primary_binfo (b
) != non_primary_binfo
)
9417 non_primary_binfo
= b
;
9420 /* Go through the virtual bases, adding the offsets. */
9421 for (vbase
= TYPE_BINFO (BINFO_TYPE (binfo
));
9423 vbase
= TREE_CHAIN (vbase
))
9428 if (!BINFO_VIRTUAL_P (vbase
))
9431 /* Find the instance of this virtual base in the complete
9433 b
= copied_binfo (vbase
, binfo
);
9435 /* If we've already got an offset for this virtual base, we
9436 don't need another one. */
9437 if (BINFO_VTABLE_PATH_MARKED (b
))
9439 BINFO_VTABLE_PATH_MARKED (b
) = 1;
9441 /* Figure out where we can find this vbase offset. */
9442 delta
= size_binop (MULT_EXPR
,
9444 fold_convert (ssizetype
,
9445 TYPE_SIZE_UNIT (vtable_entry_type
)));
9446 if (vid
->primary_vtbl_p
)
9447 BINFO_VPTR_FIELD (b
) = delta
;
9449 if (binfo
!= TYPE_BINFO (t
))
9450 /* The vbase offset had better be the same. */
9451 gcc_assert (tree_int_cst_equal (delta
, BINFO_VPTR_FIELD (vbase
)));
9453 /* The next vbase will come at a more negative offset. */
9454 vid
->index
= size_binop (MINUS_EXPR
, vid
->index
,
9455 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE
));
9457 /* The initializer is the delta from BINFO to this virtual base.
9458 The vbase offsets go in reverse inheritance-graph order, and
9459 we are walking in inheritance graph order so these end up in
9461 delta
= size_diffop_loc (input_location
,
9462 BINFO_OFFSET (b
), BINFO_OFFSET (non_primary_binfo
));
9464 CONSTRUCTOR_APPEND_ELT (vid
->inits
, NULL_TREE
,
9465 fold_build1_loc (input_location
, NOP_EXPR
,
9466 vtable_entry_type
, delta
));
9470 /* Adds the initializers for the vcall offset entries in the vtable
9471 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
9475 build_vcall_offset_vtbl_entries (tree binfo
, vtbl_init_data
* vid
)
9477 /* We only need these entries if this base is a virtual base. We
9478 compute the indices -- but do not add to the vtable -- when
9479 building the main vtable for a class. */
9480 if (binfo
== TYPE_BINFO (vid
->derived
)
9481 || (BINFO_VIRTUAL_P (binfo
)
9482 /* If BINFO is RTTI_BINFO, then (since BINFO does not
9483 correspond to VID->DERIVED), we are building a primary
9484 construction virtual table. Since this is a primary
9485 virtual table, we do not need the vcall offsets for
9487 && binfo
!= vid
->rtti_binfo
))
9489 /* We need a vcall offset for each of the virtual functions in this
9490 vtable. For example:
9492 class A { virtual void f (); };
9493 class B1 : virtual public A { virtual void f (); };
9494 class B2 : virtual public A { virtual void f (); };
9495 class C: public B1, public B2 { virtual void f (); };
9497 A C object has a primary base of B1, which has a primary base of A. A
9498 C also has a secondary base of B2, which no longer has a primary base
9499 of A. So the B2-in-C construction vtable needs a secondary vtable for
9500 A, which will adjust the A* to a B2* to call f. We have no way of
9501 knowing what (or even whether) this offset will be when we define B2,
9502 so we store this "vcall offset" in the A sub-vtable and look it up in
9503 a "virtual thunk" for B2::f.
9505 We need entries for all the functions in our primary vtable and
9506 in our non-virtual bases' secondary vtables. */
9508 /* If we are just computing the vcall indices -- but do not need
9509 the actual entries -- not that. */
9510 if (!BINFO_VIRTUAL_P (binfo
))
9511 vid
->generate_vcall_entries
= false;
9512 /* Now, walk through the non-virtual bases, adding vcall offsets. */
9513 add_vcall_offset_vtbl_entries_r (binfo
, vid
);
9517 /* Build vcall offsets, starting with those for BINFO. */
9520 add_vcall_offset_vtbl_entries_r (tree binfo
, vtbl_init_data
* vid
)
9526 /* Don't walk into virtual bases -- except, of course, for the
9527 virtual base for which we are building vcall offsets. Any
9528 primary virtual base will have already had its offsets generated
9529 through the recursion in build_vcall_and_vbase_vtbl_entries. */
9530 if (BINFO_VIRTUAL_P (binfo
) && vid
->vbase
!= binfo
)
9533 /* If BINFO has a primary base, process it first. */
9534 primary_binfo
= get_primary_binfo (binfo
);
9536 add_vcall_offset_vtbl_entries_r (primary_binfo
, vid
);
9538 /* Add BINFO itself to the list. */
9539 add_vcall_offset_vtbl_entries_1 (binfo
, vid
);
9541 /* Scan the non-primary bases of BINFO. */
9542 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); ++i
)
9543 if (base_binfo
!= primary_binfo
)
9544 add_vcall_offset_vtbl_entries_r (base_binfo
, vid
);
9547 /* Called from build_vcall_offset_vtbl_entries_r. */
9550 add_vcall_offset_vtbl_entries_1 (tree binfo
, vtbl_init_data
* vid
)
9552 /* Make entries for the rest of the virtuals. */
9555 /* The ABI requires that the methods be processed in declaration
9557 for (orig_fn
= TYPE_FIELDS (BINFO_TYPE (binfo
));
9559 orig_fn
= DECL_CHAIN (orig_fn
))
9560 if (TREE_CODE (orig_fn
) == FUNCTION_DECL
&& DECL_VINDEX (orig_fn
))
9561 add_vcall_offset (orig_fn
, binfo
, vid
);
9564 /* Add a vcall offset entry for ORIG_FN to the vtable. */
9567 add_vcall_offset (tree orig_fn
, tree binfo
, vtbl_init_data
*vid
)
9573 /* If there is already an entry for a function with the same
9574 signature as FN, then we do not need a second vcall offset.
9575 Check the list of functions already present in the derived
9577 FOR_EACH_VEC_SAFE_ELT (vid
->fns
, i
, derived_entry
)
9579 if (same_signature_p (derived_entry
, orig_fn
)
9580 /* We only use one vcall offset for virtual destructors,
9581 even though there are two virtual table entries. */
9582 || (DECL_DESTRUCTOR_P (derived_entry
)
9583 && DECL_DESTRUCTOR_P (orig_fn
)))
9587 /* If we are building these vcall offsets as part of building
9588 the vtable for the most derived class, remember the vcall
9590 if (vid
->binfo
== TYPE_BINFO (vid
->derived
))
9592 tree_pair_s elt
= {orig_fn
, vid
->index
};
9593 vec_safe_push (CLASSTYPE_VCALL_INDICES (vid
->derived
), elt
);
9596 /* The next vcall offset will be found at a more negative
9598 vid
->index
= size_binop (MINUS_EXPR
, vid
->index
,
9599 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE
));
9601 /* Keep track of this function. */
9602 vec_safe_push (vid
->fns
, orig_fn
);
9604 if (vid
->generate_vcall_entries
)
9609 /* Find the overriding function. */
9610 fn
= find_final_overrider (vid
->rtti_binfo
, binfo
, orig_fn
);
9611 if (fn
== error_mark_node
)
9612 vcall_offset
= build_zero_cst (vtable_entry_type
);
9615 base
= TREE_VALUE (fn
);
9617 /* The vbase we're working on is a primary base of
9618 vid->binfo. But it might be a lost primary, so its
9619 BINFO_OFFSET might be wrong, so we just use the
9620 BINFO_OFFSET from vid->binfo. */
9621 vcall_offset
= size_diffop_loc (input_location
,
9622 BINFO_OFFSET (base
),
9623 BINFO_OFFSET (vid
->binfo
));
9624 vcall_offset
= fold_build1_loc (input_location
,
9625 NOP_EXPR
, vtable_entry_type
,
9628 /* Add the initializer to the vtable. */
9629 CONSTRUCTOR_APPEND_ELT (vid
->inits
, NULL_TREE
, vcall_offset
);
9633 /* Return vtbl initializers for the RTTI entries corresponding to the
9634 BINFO's vtable. The RTTI entries should indicate the object given
9635 by VID->rtti_binfo. */
9638 build_rtti_vtbl_entries (tree binfo
, vtbl_init_data
* vid
)
9646 t
= BINFO_TYPE (vid
->rtti_binfo
);
9648 /* To find the complete object, we will first convert to our most
9649 primary base, and then add the offset in the vtbl to that value. */
9650 b
= most_primary_binfo (binfo
);
9651 offset
= size_diffop_loc (input_location
,
9652 BINFO_OFFSET (vid
->rtti_binfo
), BINFO_OFFSET (b
));
9654 /* The second entry is the address of the typeinfo object. */
9656 decl
= build_address (get_tinfo_decl (t
));
9658 decl
= integer_zero_node
;
9660 /* Convert the declaration to a type that can be stored in the
9662 init
= build_nop (vfunc_ptr_type_node
, decl
);
9663 CONSTRUCTOR_APPEND_ELT (vid
->inits
, NULL_TREE
, init
);
9665 /* Add the offset-to-top entry. It comes earlier in the vtable than
9666 the typeinfo entry. Convert the offset to look like a
9667 function pointer, so that we can put it in the vtable. */
9668 init
= build_nop (vfunc_ptr_type_node
, offset
);
9669 CONSTRUCTOR_APPEND_ELT (vid
->inits
, NULL_TREE
, init
);
9672 /* TRUE iff TYPE is uniquely derived from PARENT. Ignores
9676 uniquely_derived_from_p (tree parent
, tree type
)
9678 tree base
= lookup_base (type
, parent
, ba_unique
, NULL
, tf_none
);
9679 return base
&& base
!= error_mark_node
;
9682 /* TRUE iff TYPE is publicly & uniquely derived from PARENT. */
9685 publicly_uniquely_derived_p (tree parent
, tree type
)
9687 tree base
= lookup_base (type
, parent
, ba_ignore_scope
| ba_check
,
9689 return base
&& base
!= error_mark_node
;
9692 /* CTX1 and CTX2 are declaration contexts. Return the innermost common
9693 class between them, if any. */
9696 common_enclosing_class (tree ctx1
, tree ctx2
)
9698 if (!TYPE_P (ctx1
) || !TYPE_P (ctx2
))
9700 gcc_assert (ctx1
== TYPE_MAIN_VARIANT (ctx1
)
9701 && ctx2
== TYPE_MAIN_VARIANT (ctx2
));
9704 for (tree t
= ctx1
; TYPE_P (t
); t
= TYPE_CONTEXT (t
))
9705 TYPE_MARKED_P (t
) = true;
9706 tree found
= NULL_TREE
;
9707 for (tree t
= ctx2
; TYPE_P (t
); t
= TYPE_CONTEXT (t
))
9708 if (TYPE_MARKED_P (t
))
9713 for (tree t
= ctx1
; TYPE_P (t
); t
= TYPE_CONTEXT (t
))
9714 TYPE_MARKED_P (t
) = false;
9718 #include "gt-cp-class.h"