1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
38 #include "tree-dump.h"
39 #include "splay-tree.h"
40 #include "pointer-set.h"
42 /* The number of nested classes being processed. If we are not in the
43 scope of any class, this is zero. */
45 int current_class_depth;
47 /* In order to deal with nested classes, we keep a stack of classes.
48 The topmost entry is the innermost class, and is the entry at index
49 CURRENT_CLASS_DEPTH */
51 typedef struct class_stack_node {
52 /* The name of the class. */
55 /* The _TYPE node for the class. */
58 /* The access specifier pending for new declarations in the scope of
62 /* If were defining TYPE, the names used in this class. */
63 splay_tree names_used;
65 /* Nonzero if this class is no longer open, because of a call to
68 }* class_stack_node_t;
70 typedef struct vtbl_init_data_s
72 /* The base for which we're building initializers. */
74 /* The type of the most-derived type. */
76 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
77 unless ctor_vtbl_p is true. */
79 /* The negative-index vtable initializers built up so far. These
80 are in order from least negative index to most negative index. */
81 VEC(constructor_elt,gc) *inits;
82 /* The binfo for the virtual base for which we're building
83 vcall offset initializers. */
85 /* The functions in vbase for which we have already provided vcall
88 /* The vtable index of the next vcall or vbase offset. */
90 /* Nonzero if we are building the initializer for the primary
93 /* Nonzero if we are building the initializer for a construction
96 /* True when adding vcall offset entries to the vtable. False when
97 merely computing the indices. */
98 bool generate_vcall_entries;
101 /* The type of a function passed to walk_subobject_offsets. */
102 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
104 /* The stack itself. This is a dynamically resized array. The
105 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
106 static int current_class_stack_size;
107 static class_stack_node_t current_class_stack;
109 /* The size of the largest empty class seen in this translation unit. */
110 static GTY (()) tree sizeof_biggest_empty_class;
112 /* An array of all local classes present in this translation unit, in
113 declaration order. */
114 VEC(tree,gc) *local_classes;
116 static tree get_vfield_name (tree);
117 static void finish_struct_anon (tree);
118 static tree get_vtable_name (tree);
119 static tree get_basefndecls (tree, tree);
120 static int build_primary_vtable (tree, tree);
121 static int build_secondary_vtable (tree);
122 static void finish_vtbls (tree);
123 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
124 static void finish_struct_bits (tree);
125 static int alter_access (tree, tree, tree);
126 static void handle_using_decl (tree, tree);
127 static tree dfs_modify_vtables (tree, void *);
128 static tree modify_all_vtables (tree, tree);
129 static void determine_primary_bases (tree);
130 static void finish_struct_methods (tree);
131 static void maybe_warn_about_overly_private_class (tree);
132 static int method_name_cmp (const void *, const void *);
133 static int resort_method_name_cmp (const void *, const void *);
134 static void add_implicitly_declared_members (tree, int, int);
135 static tree fixed_type_or_null (tree, int *, int *);
136 static tree build_simple_base_path (tree expr, tree binfo);
137 static tree build_vtbl_ref_1 (tree, tree);
138 static void build_vtbl_initializer (tree, tree, tree, tree, int *,
139 VEC(constructor_elt,gc) **);
140 static int count_fields (tree);
141 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
142 static bool check_bitfield_decl (tree);
143 static void check_field_decl (tree, tree, int *, int *, int *);
144 static void check_field_decls (tree, tree *, int *, int *);
145 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
146 static void build_base_fields (record_layout_info, splay_tree, tree *);
147 static void check_methods (tree);
148 static void remove_zero_width_bit_fields (tree);
149 static void check_bases (tree, int *, int *);
150 static void check_bases_and_members (tree);
151 static tree create_vtable_ptr (tree, tree *);
152 static void include_empty_classes (record_layout_info);
153 static void layout_class_type (tree, tree *);
154 static void propagate_binfo_offsets (tree, tree);
155 static void layout_virtual_bases (record_layout_info, splay_tree);
156 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
157 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
158 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
159 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
160 static void add_vcall_offset (tree, tree, vtbl_init_data *);
161 static void layout_vtable_decl (tree, int);
162 static tree dfs_find_final_overrider_pre (tree, void *);
163 static tree dfs_find_final_overrider_post (tree, void *);
164 static tree find_final_overrider (tree, tree, tree);
165 static int make_new_vtable (tree, tree);
166 static tree get_primary_binfo (tree);
167 static int maybe_indent_hierarchy (FILE *, int, int);
168 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
169 static void dump_class_hierarchy (tree);
170 static void dump_class_hierarchy_1 (FILE *, int, tree);
171 static void dump_array (FILE *, tree);
172 static void dump_vtable (tree, tree, tree);
173 static void dump_vtt (tree, tree);
174 static void dump_thunk (FILE *, int, tree);
175 static tree build_vtable (tree, tree, tree);
176 static void initialize_vtable (tree, VEC(constructor_elt,gc) *);
177 static void layout_nonempty_base_or_field (record_layout_info,
178 tree, tree, splay_tree);
179 static tree end_of_class (tree, int);
180 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
181 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree,
182 VEC(constructor_elt,gc) **);
183 static void dfs_accumulate_vtbl_inits (tree, tree, tree, tree, tree,
184 VEC(constructor_elt,gc) **);
185 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
186 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
187 static void clone_constructors_and_destructors (tree);
188 static tree build_clone (tree, tree);
189 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
190 static void build_ctor_vtbl_group (tree, tree);
191 static void build_vtt (tree);
192 static tree binfo_ctor_vtable (tree);
193 static void build_vtt_inits (tree, tree, VEC(constructor_elt,gc) **, tree *);
194 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
195 static tree dfs_fixup_binfo_vtbls (tree, void *);
196 static int record_subobject_offset (tree, tree, splay_tree);
197 static int check_subobject_offset (tree, tree, splay_tree);
198 static int walk_subobject_offsets (tree, subobject_offset_fn,
199 tree, splay_tree, tree, int);
200 static void record_subobject_offsets (tree, tree, splay_tree, bool);
201 static int layout_conflict_p (tree, tree, splay_tree, int);
202 static int splay_tree_compare_integer_csts (splay_tree_key k1,
204 static void warn_about_ambiguous_bases (tree);
205 static bool type_requires_array_cookie (tree);
206 static bool contains_empty_class_p (tree);
207 static bool base_derived_from (tree, tree);
208 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
209 static tree end_of_base (tree);
210 static tree get_vcall_index (tree, tree);
212 /* Variables shared between class.c and call.c. */
214 #ifdef GATHER_STATISTICS
216 int n_vtable_entries = 0;
217 int n_vtable_searches = 0;
218 int n_vtable_elems = 0;
219 int n_convert_harshness = 0;
220 int n_compute_conversion_costs = 0;
221 int n_inner_fields_searched = 0;
224 /* Convert to or from a base subobject. EXPR is an expression of type
225 `A' or `A*', an expression of type `B' or `B*' is returned. To
226 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
227 the B base instance within A. To convert base A to derived B, CODE
228 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
229 In this latter case, A must not be a morally virtual base of B.
230 NONNULL is true if EXPR is known to be non-NULL (this is only
231 needed when EXPR is of pointer type). CV qualifiers are preserved
235 build_base_path (enum tree_code code,
239 tsubst_flags_t complain)
241 tree v_binfo = NULL_TREE;
242 tree d_binfo = NULL_TREE;
246 tree null_test = NULL;
247 tree ptr_target_type;
249 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
250 bool has_empty = false;
253 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
254 return error_mark_node;
256 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
259 if (is_empty_class (BINFO_TYPE (probe)))
261 if (!v_binfo && BINFO_VIRTUAL_P (probe))
265 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
267 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
269 gcc_assert ((code == MINUS_EXPR
270 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
271 || (code == PLUS_EXPR
272 && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
274 if (binfo == d_binfo)
278 if (code == MINUS_EXPR && v_binfo)
280 if (complain & tf_error)
281 error ("cannot convert from base %qT to derived type %qT via "
282 "virtual base %qT", BINFO_TYPE (binfo), BINFO_TYPE (d_binfo),
283 BINFO_TYPE (v_binfo));
284 return error_mark_node;
288 /* This must happen before the call to save_expr. */
289 expr = cp_build_addr_expr (expr, complain);
291 expr = mark_rvalue_use (expr);
293 offset = BINFO_OFFSET (binfo);
294 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
295 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
296 /* TARGET_TYPE has been extracted from BINFO, and, is therefore always
297 cv-unqualified. Extract the cv-qualifiers from EXPR so that the
298 expression returned matches the input. */
299 target_type = cp_build_qualified_type
300 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
301 ptr_target_type = build_pointer_type (target_type);
303 /* Do we need to look in the vtable for the real offset? */
304 virtual_access = (v_binfo && fixed_type_p <= 0);
306 /* Don't bother with the calculations inside sizeof; they'll ICE if the
307 source type is incomplete and the pointer value doesn't matter. */
308 if (cp_unevaluated_operand != 0)
310 expr = build_nop (ptr_target_type, expr);
312 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
316 /* Do we need to check for a null pointer? */
317 if (want_pointer && !nonnull)
319 /* If we know the conversion will not actually change the value
320 of EXPR, then we can avoid testing the expression for NULL.
321 We have to avoid generating a COMPONENT_REF for a base class
322 field, because other parts of the compiler know that such
323 expressions are always non-NULL. */
324 if (!virtual_access && integer_zerop (offset))
325 return build_nop (ptr_target_type, expr);
326 null_test = error_mark_node;
329 /* Protect against multiple evaluation if necessary. */
330 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
331 expr = save_expr (expr);
333 /* Now that we've saved expr, build the real null test. */
336 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
337 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
341 /* If this is a simple base reference, express it as a COMPONENT_REF. */
342 if (code == PLUS_EXPR && !virtual_access
343 /* We don't build base fields for empty bases, and they aren't very
344 interesting to the optimizers anyway. */
347 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
348 expr = build_simple_base_path (expr, binfo);
350 expr = build_address (expr);
351 target_type = TREE_TYPE (expr);
357 /* Going via virtual base V_BINFO. We need the static offset
358 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
359 V_BINFO. That offset is an entry in D_BINFO's vtable. */
362 if (fixed_type_p < 0 && in_base_initializer)
364 /* In a base member initializer, we cannot rely on the
365 vtable being set up. We have to indirect via the
369 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
370 t = build_pointer_type (t);
371 v_offset = convert (t, current_vtt_parm);
372 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
375 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, RO_NULL,
377 TREE_TYPE (TREE_TYPE (expr)));
379 v_offset = fold_build_pointer_plus (v_offset, BINFO_VPTR_FIELD (v_binfo));
380 v_offset = build1 (NOP_EXPR,
381 build_pointer_type (ptrdiff_type_node),
383 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
384 TREE_CONSTANT (v_offset) = 1;
386 offset = convert_to_integer (ptrdiff_type_node,
387 size_diffop_loc (input_location, offset,
388 BINFO_OFFSET (v_binfo)));
390 if (!integer_zerop (offset))
391 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
393 if (fixed_type_p < 0)
394 /* Negative fixed_type_p means this is a constructor or destructor;
395 virtual base layout is fixed in in-charge [cd]tors, but not in
397 offset = build3 (COND_EXPR, ptrdiff_type_node,
398 build2 (EQ_EXPR, boolean_type_node,
399 current_in_charge_parm, integer_zero_node),
401 convert_to_integer (ptrdiff_type_node,
402 BINFO_OFFSET (binfo)));
408 target_type = ptr_target_type;
410 expr = build1 (NOP_EXPR, ptr_target_type, expr);
412 if (!integer_zerop (offset))
414 offset = fold_convert (sizetype, offset);
415 if (code == MINUS_EXPR)
416 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
417 expr = fold_build_pointer_plus (expr, offset);
423 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
427 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
428 build_zero_cst (target_type));
433 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
434 Perform a derived-to-base conversion by recursively building up a
435 sequence of COMPONENT_REFs to the appropriate base fields. */
438 build_simple_base_path (tree expr, tree binfo)
440 tree type = BINFO_TYPE (binfo);
441 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
444 if (d_binfo == NULL_TREE)
448 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
450 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
451 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
452 an lvalue in the front end; only _DECLs and _REFs are lvalues
454 temp = unary_complex_lvalue (ADDR_EXPR, expr);
456 expr = cp_build_indirect_ref (temp, RO_NULL, tf_warning_or_error);
462 expr = build_simple_base_path (expr, d_binfo);
464 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
465 field; field = DECL_CHAIN (field))
466 /* Is this the base field created by build_base_field? */
467 if (TREE_CODE (field) == FIELD_DECL
468 && DECL_FIELD_IS_BASE (field)
469 && TREE_TYPE (field) == type)
471 /* We don't use build_class_member_access_expr here, as that
472 has unnecessary checks, and more importantly results in
473 recursive calls to dfs_walk_once. */
474 int type_quals = cp_type_quals (TREE_TYPE (expr));
476 expr = build3 (COMPONENT_REF,
477 cp_build_qualified_type (type, type_quals),
478 expr, field, NULL_TREE);
479 expr = fold_if_not_in_template (expr);
481 /* Mark the expression const or volatile, as appropriate.
482 Even though we've dealt with the type above, we still have
483 to mark the expression itself. */
484 if (type_quals & TYPE_QUAL_CONST)
485 TREE_READONLY (expr) = 1;
486 if (type_quals & TYPE_QUAL_VOLATILE)
487 TREE_THIS_VOLATILE (expr) = 1;
492 /* Didn't find the base field?!? */
496 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
497 type is a class type or a pointer to a class type. In the former
498 case, TYPE is also a class type; in the latter it is another
499 pointer type. If CHECK_ACCESS is true, an error message is emitted
500 if TYPE is inaccessible. If OBJECT has pointer type, the value is
501 assumed to be non-NULL. */
504 convert_to_base (tree object, tree type, bool check_access, bool nonnull,
505 tsubst_flags_t complain)
511 if (TYPE_PTR_P (TREE_TYPE (object)))
513 object_type = TREE_TYPE (TREE_TYPE (object));
514 type = TREE_TYPE (type);
517 object_type = TREE_TYPE (object);
519 access = check_access ? ba_check : ba_unique;
520 if (!(complain & tf_error))
522 binfo = lookup_base (object_type, type,
525 if (!binfo || binfo == error_mark_node)
526 return error_mark_node;
528 return build_base_path (PLUS_EXPR, object, binfo, nonnull, complain);
531 /* EXPR is an expression with unqualified class type. BASE is a base
532 binfo of that class type. Returns EXPR, converted to the BASE
533 type. This function assumes that EXPR is the most derived class;
534 therefore virtual bases can be found at their static offsets. */
537 convert_to_base_statically (tree expr, tree base)
541 expr_type = TREE_TYPE (expr);
542 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
544 /* We use fold_build2 and fold_convert below to simplify the trees
545 provided to the optimizers. It is not safe to call these functions
546 when processing a template because they do not handle C++-specific
548 gcc_assert (!processing_template_decl);
549 expr = cp_build_addr_expr (expr, tf_warning_or_error);
550 if (!integer_zerop (BINFO_OFFSET (base)))
551 expr = fold_build_pointer_plus_loc (input_location,
552 expr, BINFO_OFFSET (base));
553 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
554 expr = build_fold_indirect_ref_loc (input_location, expr);
562 build_vfield_ref (tree datum, tree type)
564 tree vfield, vcontext;
566 if (datum == error_mark_node)
567 return error_mark_node;
569 /* First, convert to the requested type. */
570 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
571 datum = convert_to_base (datum, type, /*check_access=*/false,
572 /*nonnull=*/true, tf_warning_or_error);
574 /* Second, the requested type may not be the owner of its own vptr.
575 If not, convert to the base class that owns it. We cannot use
576 convert_to_base here, because VCONTEXT may appear more than once
577 in the inheritance hierarchy of TYPE, and thus direct conversion
578 between the types may be ambiguous. Following the path back up
579 one step at a time via primary bases avoids the problem. */
580 vfield = TYPE_VFIELD (type);
581 vcontext = DECL_CONTEXT (vfield);
582 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
584 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
585 type = TREE_TYPE (datum);
588 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
591 /* Given an object INSTANCE, return an expression which yields the
592 vtable element corresponding to INDEX. There are many special
593 cases for INSTANCE which we take care of here, mainly to avoid
594 creating extra tree nodes when we don't have to. */
597 build_vtbl_ref_1 (tree instance, tree idx)
600 tree vtbl = NULL_TREE;
602 /* Try to figure out what a reference refers to, and
603 access its virtual function table directly. */
606 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
608 tree basetype = non_reference (TREE_TYPE (instance));
610 if (fixed_type && !cdtorp)
612 tree binfo = lookup_base (fixed_type, basetype,
613 ba_unique | ba_quiet, NULL);
615 vtbl = unshare_expr (BINFO_VTABLE (binfo));
619 vtbl = build_vfield_ref (instance, basetype);
621 aref = build_array_ref (input_location, vtbl, idx);
622 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
628 build_vtbl_ref (tree instance, tree idx)
630 tree aref = build_vtbl_ref_1 (instance, idx);
635 /* Given a stable object pointer INSTANCE_PTR, return an expression which
636 yields a function pointer corresponding to vtable element INDEX. */
639 build_vfn_ref (tree instance_ptr, tree idx)
643 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, RO_NULL,
644 tf_warning_or_error),
647 /* When using function descriptors, the address of the
648 vtable entry is treated as a function pointer. */
649 if (TARGET_VTABLE_USES_DESCRIPTORS)
650 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
651 cp_build_addr_expr (aref, tf_warning_or_error));
653 /* Remember this as a method reference, for later devirtualization. */
654 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
659 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
660 for the given TYPE. */
663 get_vtable_name (tree type)
665 return mangle_vtbl_for_type (type);
668 /* DECL is an entity associated with TYPE, like a virtual table or an
669 implicitly generated constructor. Determine whether or not DECL
670 should have external or internal linkage at the object file
671 level. This routine does not deal with COMDAT linkage and other
672 similar complexities; it simply sets TREE_PUBLIC if it possible for
673 entities in other translation units to contain copies of DECL, in
677 set_linkage_according_to_type (tree type ATTRIBUTE_UNUSED, tree decl)
679 TREE_PUBLIC (decl) = 1;
680 determine_visibility (decl);
683 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
684 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
685 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
688 build_vtable (tree class_type, tree name, tree vtable_type)
692 decl = build_lang_decl (VAR_DECL, name, vtable_type);
693 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
694 now to avoid confusion in mangle_decl. */
695 SET_DECL_ASSEMBLER_NAME (decl, name);
696 DECL_CONTEXT (decl) = class_type;
697 DECL_ARTIFICIAL (decl) = 1;
698 TREE_STATIC (decl) = 1;
699 TREE_READONLY (decl) = 1;
700 DECL_VIRTUAL_P (decl) = 1;
701 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
702 DECL_VTABLE_OR_VTT_P (decl) = 1;
703 /* At one time the vtable info was grabbed 2 words at a time. This
704 fails on sparc unless you have 8-byte alignment. (tiemann) */
705 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
707 set_linkage_according_to_type (class_type, decl);
708 /* The vtable has not been defined -- yet. */
709 DECL_EXTERNAL (decl) = 1;
710 DECL_NOT_REALLY_EXTERN (decl) = 1;
712 /* Mark the VAR_DECL node representing the vtable itself as a
713 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
714 is rather important that such things be ignored because any
715 effort to actually generate DWARF for them will run into
716 trouble when/if we encounter code like:
719 struct S { virtual void member (); };
721 because the artificial declaration of the vtable itself (as
722 manufactured by the g++ front end) will say that the vtable is
723 a static member of `S' but only *after* the debug output for
724 the definition of `S' has already been output. This causes
725 grief because the DWARF entry for the definition of the vtable
726 will try to refer back to an earlier *declaration* of the
727 vtable as a static member of `S' and there won't be one. We
728 might be able to arrange to have the "vtable static member"
729 attached to the member list for `S' before the debug info for
730 `S' get written (which would solve the problem) but that would
731 require more intrusive changes to the g++ front end. */
732 DECL_IGNORED_P (decl) = 1;
737 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
738 or even complete. If this does not exist, create it. If COMPLETE is
739 nonzero, then complete the definition of it -- that will render it
740 impossible to actually build the vtable, but is useful to get at those
741 which are known to exist in the runtime. */
744 get_vtable_decl (tree type, int complete)
748 if (CLASSTYPE_VTABLES (type))
749 return CLASSTYPE_VTABLES (type);
751 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
752 CLASSTYPE_VTABLES (type) = decl;
756 DECL_EXTERNAL (decl) = 1;
757 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
763 /* Build the primary virtual function table for TYPE. If BINFO is
764 non-NULL, build the vtable starting with the initial approximation
765 that it is the same as the one which is the head of the association
766 list. Returns a nonzero value if a new vtable is actually
770 build_primary_vtable (tree binfo, tree type)
775 decl = get_vtable_decl (type, /*complete=*/0);
779 if (BINFO_NEW_VTABLE_MARKED (binfo))
780 /* We have already created a vtable for this base, so there's
781 no need to do it again. */
784 virtuals = copy_list (BINFO_VIRTUALS (binfo));
785 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
786 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
787 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
791 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
792 virtuals = NULL_TREE;
795 #ifdef GATHER_STATISTICS
797 n_vtable_elems += list_length (virtuals);
800 /* Initialize the association list for this type, based
801 on our first approximation. */
802 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
803 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
804 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
808 /* Give BINFO a new virtual function table which is initialized
809 with a skeleton-copy of its original initialization. The only
810 entry that changes is the `delta' entry, so we can really
811 share a lot of structure.
813 FOR_TYPE is the most derived type which caused this table to
816 Returns nonzero if we haven't met BINFO before.
818 The order in which vtables are built (by calling this function) for
819 an object must remain the same, otherwise a binary incompatibility
823 build_secondary_vtable (tree binfo)
825 if (BINFO_NEW_VTABLE_MARKED (binfo))
826 /* We already created a vtable for this base. There's no need to
830 /* Remember that we've created a vtable for this BINFO, so that we
831 don't try to do so again. */
832 SET_BINFO_NEW_VTABLE_MARKED (binfo);
834 /* Make fresh virtual list, so we can smash it later. */
835 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
837 /* Secondary vtables are laid out as part of the same structure as
838 the primary vtable. */
839 BINFO_VTABLE (binfo) = NULL_TREE;
843 /* Create a new vtable for BINFO which is the hierarchy dominated by
844 T. Return nonzero if we actually created a new vtable. */
847 make_new_vtable (tree t, tree binfo)
849 if (binfo == TYPE_BINFO (t))
850 /* In this case, it is *type*'s vtable we are modifying. We start
851 with the approximation that its vtable is that of the
852 immediate base class. */
853 return build_primary_vtable (binfo, t);
855 /* This is our very own copy of `basetype' to play with. Later,
856 we will fill in all the virtual functions that override the
857 virtual functions in these base classes which are not defined
858 by the current type. */
859 return build_secondary_vtable (binfo);
862 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
863 (which is in the hierarchy dominated by T) list FNDECL as its
864 BV_FN. DELTA is the required constant adjustment from the `this'
865 pointer where the vtable entry appears to the `this' required when
866 the function is actually called. */
869 modify_vtable_entry (tree t,
879 if (fndecl != BV_FN (v)
880 || !tree_int_cst_equal (delta, BV_DELTA (v)))
882 /* We need a new vtable for BINFO. */
883 if (make_new_vtable (t, binfo))
885 /* If we really did make a new vtable, we also made a copy
886 of the BINFO_VIRTUALS list. Now, we have to find the
887 corresponding entry in that list. */
888 *virtuals = BINFO_VIRTUALS (binfo);
889 while (BV_FN (*virtuals) != BV_FN (v))
890 *virtuals = TREE_CHAIN (*virtuals);
894 BV_DELTA (v) = delta;
895 BV_VCALL_INDEX (v) = NULL_TREE;
901 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
902 the USING_DECL naming METHOD. Returns true if the method could be
903 added to the method vec. */
906 add_method (tree type, tree method, tree using_decl)
910 bool template_conv_p = false;
912 VEC(tree,gc) *method_vec;
914 bool insert_p = false;
918 if (method == error_mark_node)
921 complete_p = COMPLETE_TYPE_P (type);
922 conv_p = DECL_CONV_FN_P (method);
924 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
925 && DECL_TEMPLATE_CONV_FN_P (method));
927 method_vec = CLASSTYPE_METHOD_VEC (type);
930 /* Make a new method vector. We start with 8 entries. We must
931 allocate at least two (for constructors and destructors), and
932 we're going to end up with an assignment operator at some
934 method_vec = VEC_alloc (tree, gc, 8);
935 /* Create slots for constructors and destructors. */
936 VEC_quick_push (tree, method_vec, NULL_TREE);
937 VEC_quick_push (tree, method_vec, NULL_TREE);
938 CLASSTYPE_METHOD_VEC (type) = method_vec;
941 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
942 grok_special_member_properties (method);
944 /* Constructors and destructors go in special slots. */
945 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
946 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
947 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
949 slot = CLASSTYPE_DESTRUCTOR_SLOT;
951 if (TYPE_FOR_JAVA (type))
953 if (!DECL_ARTIFICIAL (method))
954 error ("Java class %qT cannot have a destructor", type);
955 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
956 error ("Java class %qT cannot have an implicit non-trivial "
966 /* See if we already have an entry with this name. */
967 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
968 VEC_iterate (tree, method_vec, slot, m);
974 if (TREE_CODE (m) == TEMPLATE_DECL
975 && DECL_TEMPLATE_CONV_FN_P (m))
979 if (conv_p && !DECL_CONV_FN_P (m))
981 if (DECL_NAME (m) == DECL_NAME (method))
987 && !DECL_CONV_FN_P (m)
988 && DECL_NAME (m) > DECL_NAME (method))
992 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
994 /* Check to see if we've already got this method. */
995 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
997 tree fn = OVL_CURRENT (fns);
1003 if (TREE_CODE (fn) != TREE_CODE (method))
1006 /* [over.load] Member function declarations with the
1007 same name and the same parameter types cannot be
1008 overloaded if any of them is a static member
1009 function declaration.
1011 [namespace.udecl] When a using-declaration brings names
1012 from a base class into a derived class scope, member
1013 functions in the derived class override and/or hide member
1014 functions with the same name and parameter types in a base
1015 class (rather than conflicting). */
1016 fn_type = TREE_TYPE (fn);
1017 method_type = TREE_TYPE (method);
1018 parms1 = TYPE_ARG_TYPES (fn_type);
1019 parms2 = TYPE_ARG_TYPES (method_type);
1021 /* Compare the quals on the 'this' parm. Don't compare
1022 the whole types, as used functions are treated as
1023 coming from the using class in overload resolution. */
1024 if (! DECL_STATIC_FUNCTION_P (fn)
1025 && ! DECL_STATIC_FUNCTION_P (method)
1026 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1027 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1028 && (cp_type_quals (TREE_TYPE (TREE_VALUE (parms1)))
1029 != cp_type_quals (TREE_TYPE (TREE_VALUE (parms2)))))
1032 /* For templates, the return type and template parameters
1033 must be identical. */
1034 if (TREE_CODE (fn) == TEMPLATE_DECL
1035 && (!same_type_p (TREE_TYPE (fn_type),
1036 TREE_TYPE (method_type))
1037 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1038 DECL_TEMPLATE_PARMS (method))))
1041 if (! DECL_STATIC_FUNCTION_P (fn))
1042 parms1 = TREE_CHAIN (parms1);
1043 if (! DECL_STATIC_FUNCTION_P (method))
1044 parms2 = TREE_CHAIN (parms2);
1046 if (compparms (parms1, parms2)
1047 && (!DECL_CONV_FN_P (fn)
1048 || same_type_p (TREE_TYPE (fn_type),
1049 TREE_TYPE (method_type))))
1053 if (DECL_CONTEXT (fn) == type)
1054 /* Defer to the local function. */
1056 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1057 error ("repeated using declaration %q+D", using_decl);
1059 error ("using declaration %q+D conflicts with a previous using declaration",
1064 error ("%q+#D cannot be overloaded", method);
1065 error ("with %q+#D", fn);
1068 /* We don't call duplicate_decls here to merge the
1069 declarations because that will confuse things if the
1070 methods have inline definitions. In particular, we
1071 will crash while processing the definitions. */
1076 /* A class should never have more than one destructor. */
1077 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1080 /* Add the new binding. */
1081 overload = build_overload (method, current_fns);
1084 TYPE_HAS_CONVERSION (type) = 1;
1085 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1086 push_class_level_binding (DECL_NAME (method), overload);
1092 /* We only expect to add few methods in the COMPLETE_P case, so
1093 just make room for one more method in that case. */
1095 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1097 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1099 CLASSTYPE_METHOD_VEC (type) = method_vec;
1100 if (slot == VEC_length (tree, method_vec))
1101 VEC_quick_push (tree, method_vec, overload);
1103 VEC_quick_insert (tree, method_vec, slot, overload);
1106 /* Replace the current slot. */
1107 VEC_replace (tree, method_vec, slot, overload);
1111 /* Subroutines of finish_struct. */
1113 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1114 legit, otherwise return 0. */
1117 alter_access (tree t, tree fdecl, tree access)
1121 if (!DECL_LANG_SPECIFIC (fdecl))
1122 retrofit_lang_decl (fdecl);
1124 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1126 elem = purpose_member (t, DECL_ACCESS (fdecl));
1129 if (TREE_VALUE (elem) != access)
1131 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1132 error ("conflicting access specifications for method"
1133 " %q+D, ignored", TREE_TYPE (fdecl));
1135 error ("conflicting access specifications for field %qE, ignored",
1140 /* They're changing the access to the same thing they changed
1141 it to before. That's OK. */
1147 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1148 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1154 /* Process the USING_DECL, which is a member of T. */
1157 handle_using_decl (tree using_decl, tree t)
1159 tree decl = USING_DECL_DECLS (using_decl);
1160 tree name = DECL_NAME (using_decl);
1162 = TREE_PRIVATE (using_decl) ? access_private_node
1163 : TREE_PROTECTED (using_decl) ? access_protected_node
1164 : access_public_node;
1165 tree flist = NULL_TREE;
1168 gcc_assert (!processing_template_decl && decl);
1170 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1173 if (is_overloaded_fn (old_value))
1174 old_value = OVL_CURRENT (old_value);
1176 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1179 old_value = NULL_TREE;
1182 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1184 if (is_overloaded_fn (decl))
1189 else if (is_overloaded_fn (old_value))
1192 /* It's OK to use functions from a base when there are functions with
1193 the same name already present in the current class. */;
1196 error ("%q+D invalid in %q#T", using_decl, t);
1197 error (" because of local method %q+#D with same name",
1198 OVL_CURRENT (old_value));
1202 else if (!DECL_ARTIFICIAL (old_value))
1204 error ("%q+D invalid in %q#T", using_decl, t);
1205 error (" because of local member %q+#D with same name", old_value);
1209 /* Make type T see field decl FDECL with access ACCESS. */
1211 for (; flist; flist = OVL_NEXT (flist))
1213 add_method (t, OVL_CURRENT (flist), using_decl);
1214 alter_access (t, OVL_CURRENT (flist), access);
1217 alter_access (t, decl, access);
1220 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1221 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1222 properties of the bases. */
1225 check_bases (tree t,
1226 int* cant_have_const_ctor_p,
1227 int* no_const_asn_ref_p)
1230 int seen_non_virtual_nearly_empty_base_p;
1233 tree field = NULL_TREE;
1235 seen_non_virtual_nearly_empty_base_p = 0;
1237 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1238 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
1239 if (TREE_CODE (field) == FIELD_DECL)
1242 for (binfo = TYPE_BINFO (t), i = 0;
1243 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1245 tree basetype = TREE_TYPE (base_binfo);
1247 gcc_assert (COMPLETE_TYPE_P (basetype));
1249 if (CLASSTYPE_FINAL (basetype))
1250 error ("cannot derive from %<final%> base %qT in derived type %qT",
1253 /* If any base class is non-literal, so is the derived class. */
1254 if (!CLASSTYPE_LITERAL_P (basetype))
1255 CLASSTYPE_LITERAL_P (t) = false;
1257 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1258 here because the case of virtual functions but non-virtual
1259 dtor is handled in finish_struct_1. */
1260 if (!TYPE_POLYMORPHIC_P (basetype))
1261 warning (OPT_Weffc__,
1262 "base class %q#T has a non-virtual destructor", basetype);
1264 /* If the base class doesn't have copy constructors or
1265 assignment operators that take const references, then the
1266 derived class cannot have such a member automatically
1268 if (TYPE_HAS_COPY_CTOR (basetype)
1269 && ! TYPE_HAS_CONST_COPY_CTOR (basetype))
1270 *cant_have_const_ctor_p = 1;
1271 if (TYPE_HAS_COPY_ASSIGN (basetype)
1272 && !TYPE_HAS_CONST_COPY_ASSIGN (basetype))
1273 *no_const_asn_ref_p = 1;
1275 if (BINFO_VIRTUAL_P (base_binfo))
1276 /* A virtual base does not effect nearly emptiness. */
1278 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1280 if (seen_non_virtual_nearly_empty_base_p)
1281 /* And if there is more than one nearly empty base, then the
1282 derived class is not nearly empty either. */
1283 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1285 /* Remember we've seen one. */
1286 seen_non_virtual_nearly_empty_base_p = 1;
1288 else if (!is_empty_class (basetype))
1289 /* If the base class is not empty or nearly empty, then this
1290 class cannot be nearly empty. */
1291 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1293 /* A lot of properties from the bases also apply to the derived
1295 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1296 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1297 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1298 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
1299 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (basetype)
1300 || !TYPE_HAS_COPY_ASSIGN (basetype));
1301 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (basetype)
1302 || !TYPE_HAS_COPY_CTOR (basetype));
1303 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t)
1304 |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (basetype);
1305 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (basetype);
1306 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1307 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1308 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1309 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
1310 || TYPE_HAS_COMPLEX_DFLT (basetype));
1312 /* A standard-layout class is a class that:
1314 * has no non-standard-layout base classes, */
1315 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1316 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1319 /* ...has no base classes of the same type as the first non-static
1321 if (field && DECL_CONTEXT (field) == t
1322 && (same_type_ignoring_top_level_qualifiers_p
1323 (TREE_TYPE (field), basetype)))
1324 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1326 /* ...either has no non-static data members in the most-derived
1327 class and at most one base class with non-static data
1328 members, or has no base classes with non-static data
1330 for (basefield = TYPE_FIELDS (basetype); basefield;
1331 basefield = DECL_CHAIN (basefield))
1332 if (TREE_CODE (basefield) == FIELD_DECL)
1335 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1344 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1345 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1346 that have had a nearly-empty virtual primary base stolen by some
1347 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1351 determine_primary_bases (tree t)
1354 tree primary = NULL_TREE;
1355 tree type_binfo = TYPE_BINFO (t);
1358 /* Determine the primary bases of our bases. */
1359 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1360 base_binfo = TREE_CHAIN (base_binfo))
1362 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1364 /* See if we're the non-virtual primary of our inheritance
1366 if (!BINFO_VIRTUAL_P (base_binfo))
1368 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1369 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1372 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1373 BINFO_TYPE (parent_primary)))
1374 /* We are the primary binfo. */
1375 BINFO_PRIMARY_P (base_binfo) = 1;
1377 /* Determine if we have a virtual primary base, and mark it so.
1379 if (primary && BINFO_VIRTUAL_P (primary))
1381 tree this_primary = copied_binfo (primary, base_binfo);
1383 if (BINFO_PRIMARY_P (this_primary))
1384 /* Someone already claimed this base. */
1385 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1390 BINFO_PRIMARY_P (this_primary) = 1;
1391 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1393 /* A virtual binfo might have been copied from within
1394 another hierarchy. As we're about to use it as a
1395 primary base, make sure the offsets match. */
1396 delta = size_diffop_loc (input_location,
1398 BINFO_OFFSET (base_binfo)),
1400 BINFO_OFFSET (this_primary)));
1402 propagate_binfo_offsets (this_primary, delta);
1407 /* First look for a dynamic direct non-virtual base. */
1408 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1410 tree basetype = BINFO_TYPE (base_binfo);
1412 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1414 primary = base_binfo;
1419 /* A "nearly-empty" virtual base class can be the primary base
1420 class, if no non-virtual polymorphic base can be found. Look for
1421 a nearly-empty virtual dynamic base that is not already a primary
1422 base of something in the hierarchy. If there is no such base,
1423 just pick the first nearly-empty virtual base. */
1425 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1426 base_binfo = TREE_CHAIN (base_binfo))
1427 if (BINFO_VIRTUAL_P (base_binfo)
1428 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1430 if (!BINFO_PRIMARY_P (base_binfo))
1432 /* Found one that is not primary. */
1433 primary = base_binfo;
1437 /* Remember the first candidate. */
1438 primary = base_binfo;
1442 /* If we've got a primary base, use it. */
1445 tree basetype = BINFO_TYPE (primary);
1447 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1448 if (BINFO_PRIMARY_P (primary))
1449 /* We are stealing a primary base. */
1450 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1451 BINFO_PRIMARY_P (primary) = 1;
1452 if (BINFO_VIRTUAL_P (primary))
1456 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1457 /* A virtual binfo might have been copied from within
1458 another hierarchy. As we're about to use it as a primary
1459 base, make sure the offsets match. */
1460 delta = size_diffop_loc (input_location, ssize_int (0),
1461 convert (ssizetype, BINFO_OFFSET (primary)));
1463 propagate_binfo_offsets (primary, delta);
1466 primary = TYPE_BINFO (basetype);
1468 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1469 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1470 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1474 /* Update the variant types of T. */
1477 fixup_type_variants (tree t)
1484 for (variants = TYPE_NEXT_VARIANT (t);
1486 variants = TYPE_NEXT_VARIANT (variants))
1488 /* These fields are in the _TYPE part of the node, not in
1489 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1490 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1491 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1492 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1493 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1495 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1497 TYPE_BINFO (variants) = TYPE_BINFO (t);
1499 /* Copy whatever these are holding today. */
1500 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1501 TYPE_METHODS (variants) = TYPE_METHODS (t);
1502 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1506 /* Early variant fixups: we apply attributes at the beginning of the class
1507 definition, and we need to fix up any variants that have already been
1508 made via elaborated-type-specifier so that check_qualified_type works. */
1511 fixup_attribute_variants (tree t)
1518 for (variants = TYPE_NEXT_VARIANT (t);
1520 variants = TYPE_NEXT_VARIANT (variants))
1522 /* These are the two fields that check_qualified_type looks at and
1523 are affected by attributes. */
1524 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1525 TYPE_ALIGN (variants) = TYPE_ALIGN (t);
1529 /* Set memoizing fields and bits of T (and its variants) for later
1533 finish_struct_bits (tree t)
1535 /* Fix up variants (if any). */
1536 fixup_type_variants (t);
1538 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1539 /* For a class w/o baseclasses, 'finish_struct' has set
1540 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1541 Similarly for a class whose base classes do not have vtables.
1542 When neither of these is true, we might have removed abstract
1543 virtuals (by providing a definition), added some (by declaring
1544 new ones), or redeclared ones from a base class. We need to
1545 recalculate what's really an abstract virtual at this point (by
1546 looking in the vtables). */
1547 get_pure_virtuals (t);
1549 /* If this type has a copy constructor or a destructor, force its
1550 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1551 nonzero. This will cause it to be passed by invisible reference
1552 and prevent it from being returned in a register. */
1553 if (type_has_nontrivial_copy_init (t)
1554 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1557 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1558 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1560 SET_TYPE_MODE (variants, BLKmode);
1561 TREE_ADDRESSABLE (variants) = 1;
1566 /* Issue warnings about T having private constructors, but no friends,
1569 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1570 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1571 non-private static member functions. */
1574 maybe_warn_about_overly_private_class (tree t)
1576 int has_member_fn = 0;
1577 int has_nonprivate_method = 0;
1580 if (!warn_ctor_dtor_privacy
1581 /* If the class has friends, those entities might create and
1582 access instances, so we should not warn. */
1583 || (CLASSTYPE_FRIEND_CLASSES (t)
1584 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1585 /* We will have warned when the template was declared; there's
1586 no need to warn on every instantiation. */
1587 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1588 /* There's no reason to even consider warning about this
1592 /* We only issue one warning, if more than one applies, because
1593 otherwise, on code like:
1596 // Oops - forgot `public:'
1602 we warn several times about essentially the same problem. */
1604 /* Check to see if all (non-constructor, non-destructor) member
1605 functions are private. (Since there are no friends or
1606 non-private statics, we can't ever call any of the private member
1608 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
1609 /* We're not interested in compiler-generated methods; they don't
1610 provide any way to call private members. */
1611 if (!DECL_ARTIFICIAL (fn))
1613 if (!TREE_PRIVATE (fn))
1615 if (DECL_STATIC_FUNCTION_P (fn))
1616 /* A non-private static member function is just like a
1617 friend; it can create and invoke private member
1618 functions, and be accessed without a class
1622 has_nonprivate_method = 1;
1623 /* Keep searching for a static member function. */
1625 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1629 if (!has_nonprivate_method && has_member_fn)
1631 /* There are no non-private methods, and there's at least one
1632 private member function that isn't a constructor or
1633 destructor. (If all the private members are
1634 constructors/destructors we want to use the code below that
1635 issues error messages specifically referring to
1636 constructors/destructors.) */
1638 tree binfo = TYPE_BINFO (t);
1640 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1641 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1643 has_nonprivate_method = 1;
1646 if (!has_nonprivate_method)
1648 warning (OPT_Wctor_dtor_privacy,
1649 "all member functions in class %qT are private", t);
1654 /* Even if some of the member functions are non-private, the class
1655 won't be useful for much if all the constructors or destructors
1656 are private: such an object can never be created or destroyed. */
1657 fn = CLASSTYPE_DESTRUCTORS (t);
1658 if (fn && TREE_PRIVATE (fn))
1660 warning (OPT_Wctor_dtor_privacy,
1661 "%q#T only defines a private destructor and has no friends",
1666 /* Warn about classes that have private constructors and no friends. */
1667 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1668 /* Implicitly generated constructors are always public. */
1669 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1670 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1672 int nonprivate_ctor = 0;
1674 /* If a non-template class does not define a copy
1675 constructor, one is defined for it, enabling it to avoid
1676 this warning. For a template class, this does not
1677 happen, and so we would normally get a warning on:
1679 template <class T> class C { private: C(); };
1681 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1682 complete non-template or fully instantiated classes have this
1684 if (!TYPE_HAS_COPY_CTOR (t))
1685 nonprivate_ctor = 1;
1687 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1689 tree ctor = OVL_CURRENT (fn);
1690 /* Ideally, we wouldn't count copy constructors (or, in
1691 fact, any constructor that takes an argument of the
1692 class type as a parameter) because such things cannot
1693 be used to construct an instance of the class unless
1694 you already have one. But, for now at least, we're
1696 if (! TREE_PRIVATE (ctor))
1698 nonprivate_ctor = 1;
1703 if (nonprivate_ctor == 0)
1705 warning (OPT_Wctor_dtor_privacy,
1706 "%q#T only defines private constructors and has no friends",
1714 gt_pointer_operator new_value;
1718 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1721 method_name_cmp (const void* m1_p, const void* m2_p)
1723 const tree *const m1 = (const tree *) m1_p;
1724 const tree *const m2 = (const tree *) m2_p;
1726 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1728 if (*m1 == NULL_TREE)
1730 if (*m2 == NULL_TREE)
1732 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1737 /* This routine compares two fields like method_name_cmp but using the
1738 pointer operator in resort_field_decl_data. */
1741 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1743 const tree *const m1 = (const tree *) m1_p;
1744 const tree *const m2 = (const tree *) m2_p;
1745 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1747 if (*m1 == NULL_TREE)
1749 if (*m2 == NULL_TREE)
1752 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1753 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1754 resort_data.new_value (&d1, resort_data.cookie);
1755 resort_data.new_value (&d2, resort_data.cookie);
1762 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1765 resort_type_method_vec (void* obj,
1766 void* orig_obj ATTRIBUTE_UNUSED ,
1767 gt_pointer_operator new_value,
1770 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1771 int len = VEC_length (tree, method_vec);
1775 /* The type conversion ops have to live at the front of the vec, so we
1777 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1778 VEC_iterate (tree, method_vec, slot, fn);
1780 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1785 resort_data.new_value = new_value;
1786 resort_data.cookie = cookie;
1787 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1788 resort_method_name_cmp);
1792 /* Warn about duplicate methods in fn_fields.
1794 Sort methods that are not special (i.e., constructors, destructors,
1795 and type conversion operators) so that we can find them faster in
1799 finish_struct_methods (tree t)
1802 VEC(tree,gc) *method_vec;
1805 method_vec = CLASSTYPE_METHOD_VEC (t);
1809 len = VEC_length (tree, method_vec);
1811 /* Clear DECL_IN_AGGR_P for all functions. */
1812 for (fn_fields = TYPE_METHODS (t); fn_fields;
1813 fn_fields = DECL_CHAIN (fn_fields))
1814 DECL_IN_AGGR_P (fn_fields) = 0;
1816 /* Issue warnings about private constructors and such. If there are
1817 no methods, then some public defaults are generated. */
1818 maybe_warn_about_overly_private_class (t);
1820 /* The type conversion ops have to live at the front of the vec, so we
1822 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1823 VEC_iterate (tree, method_vec, slot, fn_fields);
1825 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1828 qsort (VEC_address (tree, method_vec) + slot,
1829 len-slot, sizeof (tree), method_name_cmp);
1832 /* Make BINFO's vtable have N entries, including RTTI entries,
1833 vbase and vcall offsets, etc. Set its type and call the back end
1837 layout_vtable_decl (tree binfo, int n)
1842 atype = build_array_of_n_type (vtable_entry_type, n);
1843 layout_type (atype);
1845 /* We may have to grow the vtable. */
1846 vtable = get_vtbl_decl_for_binfo (binfo);
1847 if (!same_type_p (TREE_TYPE (vtable), atype))
1849 TREE_TYPE (vtable) = atype;
1850 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1851 layout_decl (vtable, 0);
1855 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1856 have the same signature. */
1859 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1861 /* One destructor overrides another if they are the same kind of
1863 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1864 && special_function_p (base_fndecl) == special_function_p (fndecl))
1866 /* But a non-destructor never overrides a destructor, nor vice
1867 versa, nor do different kinds of destructors override
1868 one-another. For example, a complete object destructor does not
1869 override a deleting destructor. */
1870 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1873 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1874 || (DECL_CONV_FN_P (fndecl)
1875 && DECL_CONV_FN_P (base_fndecl)
1876 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1877 DECL_CONV_FN_TYPE (base_fndecl))))
1879 tree types, base_types;
1880 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1881 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1882 if ((cp_type_quals (TREE_TYPE (TREE_VALUE (base_types)))
1883 == cp_type_quals (TREE_TYPE (TREE_VALUE (types))))
1884 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1890 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1894 base_derived_from (tree derived, tree base)
1898 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1900 if (probe == derived)
1902 else if (BINFO_VIRTUAL_P (probe))
1903 /* If we meet a virtual base, we can't follow the inheritance
1904 any more. See if the complete type of DERIVED contains
1905 such a virtual base. */
1906 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1912 typedef struct find_final_overrider_data_s {
1913 /* The function for which we are trying to find a final overrider. */
1915 /* The base class in which the function was declared. */
1916 tree declaring_base;
1917 /* The candidate overriders. */
1919 /* Path to most derived. */
1920 VEC(tree,heap) *path;
1921 } find_final_overrider_data;
1923 /* Add the overrider along the current path to FFOD->CANDIDATES.
1924 Returns true if an overrider was found; false otherwise. */
1927 dfs_find_final_overrider_1 (tree binfo,
1928 find_final_overrider_data *ffod,
1933 /* If BINFO is not the most derived type, try a more derived class.
1934 A definition there will overrider a definition here. */
1938 if (dfs_find_final_overrider_1
1939 (VEC_index (tree, ffod->path, depth), ffod, depth))
1943 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1946 tree *candidate = &ffod->candidates;
1948 /* Remove any candidates overridden by this new function. */
1951 /* If *CANDIDATE overrides METHOD, then METHOD
1952 cannot override anything else on the list. */
1953 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1955 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1956 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1957 *candidate = TREE_CHAIN (*candidate);
1959 candidate = &TREE_CHAIN (*candidate);
1962 /* Add the new function. */
1963 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1970 /* Called from find_final_overrider via dfs_walk. */
1973 dfs_find_final_overrider_pre (tree binfo, void *data)
1975 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1977 if (binfo == ffod->declaring_base)
1978 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1979 VEC_safe_push (tree, heap, ffod->path, binfo);
1985 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1987 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1988 VEC_pop (tree, ffod->path);
1993 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1994 FN and whose TREE_VALUE is the binfo for the base where the
1995 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1996 DERIVED) is the base object in which FN is declared. */
1999 find_final_overrider (tree derived, tree binfo, tree fn)
2001 find_final_overrider_data ffod;
2003 /* Getting this right is a little tricky. This is valid:
2005 struct S { virtual void f (); };
2006 struct T { virtual void f (); };
2007 struct U : public S, public T { };
2009 even though calling `f' in `U' is ambiguous. But,
2011 struct R { virtual void f(); };
2012 struct S : virtual public R { virtual void f (); };
2013 struct T : virtual public R { virtual void f (); };
2014 struct U : public S, public T { };
2016 is not -- there's no way to decide whether to put `S::f' or
2017 `T::f' in the vtable for `R'.
2019 The solution is to look at all paths to BINFO. If we find
2020 different overriders along any two, then there is a problem. */
2021 if (DECL_THUNK_P (fn))
2022 fn = THUNK_TARGET (fn);
2024 /* Determine the depth of the hierarchy. */
2026 ffod.declaring_base = binfo;
2027 ffod.candidates = NULL_TREE;
2028 ffod.path = VEC_alloc (tree, heap, 30);
2030 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2031 dfs_find_final_overrider_post, &ffod);
2033 VEC_free (tree, heap, ffod.path);
2035 /* If there was no winner, issue an error message. */
2036 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2037 return error_mark_node;
2039 return ffod.candidates;
2042 /* Return the index of the vcall offset for FN when TYPE is used as a
2046 get_vcall_index (tree fn, tree type)
2048 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2052 FOR_EACH_VEC_ELT (tree_pair_s, indices, ix, p)
2053 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2054 || same_signature_p (fn, p->purpose))
2057 /* There should always be an appropriate index. */
2061 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2062 dominated by T. FN is the old function; VIRTUALS points to the
2063 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2064 of that entry in the list. */
2067 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2075 tree overrider_fn, overrider_target;
2076 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2077 tree over_return, base_return;
2080 /* Find the nearest primary base (possibly binfo itself) which defines
2081 this function; this is the class the caller will convert to when
2082 calling FN through BINFO. */
2083 for (b = binfo; ; b = get_primary_binfo (b))
2086 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2089 /* The nearest definition is from a lost primary. */
2090 if (BINFO_LOST_PRIMARY_P (b))
2095 /* Find the final overrider. */
2096 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2097 if (overrider == error_mark_node)
2099 error ("no unique final overrider for %qD in %qT", target_fn, t);
2102 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2104 /* Check for adjusting covariant return types. */
2105 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2106 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2108 if (POINTER_TYPE_P (over_return)
2109 && TREE_CODE (over_return) == TREE_CODE (base_return)
2110 && CLASS_TYPE_P (TREE_TYPE (over_return))
2111 && CLASS_TYPE_P (TREE_TYPE (base_return))
2112 /* If the overrider is invalid, don't even try. */
2113 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2115 /* If FN is a covariant thunk, we must figure out the adjustment
2116 to the final base FN was converting to. As OVERRIDER_TARGET might
2117 also be converting to the return type of FN, we have to
2118 combine the two conversions here. */
2119 tree fixed_offset, virtual_offset;
2121 over_return = TREE_TYPE (over_return);
2122 base_return = TREE_TYPE (base_return);
2124 if (DECL_THUNK_P (fn))
2126 gcc_assert (DECL_RESULT_THUNK_P (fn));
2127 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2128 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2131 fixed_offset = virtual_offset = NULL_TREE;
2134 /* Find the equivalent binfo within the return type of the
2135 overriding function. We will want the vbase offset from
2137 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2139 else if (!same_type_ignoring_top_level_qualifiers_p
2140 (over_return, base_return))
2142 /* There was no existing virtual thunk (which takes
2143 precedence). So find the binfo of the base function's
2144 return type within the overriding function's return type.
2145 We cannot call lookup base here, because we're inside a
2146 dfs_walk, and will therefore clobber the BINFO_MARKED
2147 flags. Fortunately we know the covariancy is valid (it
2148 has already been checked), so we can just iterate along
2149 the binfos, which have been chained in inheritance graph
2150 order. Of course it is lame that we have to repeat the
2151 search here anyway -- we should really be caching pieces
2152 of the vtable and avoiding this repeated work. */
2153 tree thunk_binfo, base_binfo;
2155 /* Find the base binfo within the overriding function's
2156 return type. We will always find a thunk_binfo, except
2157 when the covariancy is invalid (which we will have
2158 already diagnosed). */
2159 for (base_binfo = TYPE_BINFO (base_return),
2160 thunk_binfo = TYPE_BINFO (over_return);
2162 thunk_binfo = TREE_CHAIN (thunk_binfo))
2163 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2164 BINFO_TYPE (base_binfo)))
2167 /* See if virtual inheritance is involved. */
2168 for (virtual_offset = thunk_binfo;
2170 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2171 if (BINFO_VIRTUAL_P (virtual_offset))
2175 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2177 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2181 /* We convert via virtual base. Adjust the fixed
2182 offset to be from there. */
2184 size_diffop (offset,
2186 BINFO_OFFSET (virtual_offset)));
2189 /* There was an existing fixed offset, this must be
2190 from the base just converted to, and the base the
2191 FN was thunking to. */
2192 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2194 fixed_offset = offset;
2198 if (fixed_offset || virtual_offset)
2199 /* Replace the overriding function with a covariant thunk. We
2200 will emit the overriding function in its own slot as
2202 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2203 fixed_offset, virtual_offset);
2206 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2207 !DECL_THUNK_P (fn));
2209 /* If we need a covariant thunk, then we may need to adjust first_defn.
2210 The ABI specifies that the thunks emitted with a function are
2211 determined by which bases the function overrides, so we need to be
2212 sure that we're using a thunk for some overridden base; even if we
2213 know that the necessary this adjustment is zero, there may not be an
2214 appropriate zero-this-adjusment thunk for us to use since thunks for
2215 overriding virtual bases always use the vcall offset.
2217 Furthermore, just choosing any base that overrides this function isn't
2218 quite right, as this slot won't be used for calls through a type that
2219 puts a covariant thunk here. Calling the function through such a type
2220 will use a different slot, and that slot is the one that determines
2221 the thunk emitted for that base.
2223 So, keep looking until we find the base that we're really overriding
2224 in this slot: the nearest primary base that doesn't use a covariant
2225 thunk in this slot. */
2226 if (overrider_target != overrider_fn)
2228 if (BINFO_TYPE (b) == DECL_CONTEXT (overrider_target))
2229 /* We already know that the overrider needs a covariant thunk. */
2230 b = get_primary_binfo (b);
2231 for (; ; b = get_primary_binfo (b))
2233 tree main_binfo = TYPE_BINFO (BINFO_TYPE (b));
2234 tree bv = chain_index (ix, BINFO_VIRTUALS (main_binfo));
2235 if (!DECL_THUNK_P (TREE_VALUE (bv)))
2237 if (BINFO_LOST_PRIMARY_P (b))
2243 /* Assume that we will produce a thunk that convert all the way to
2244 the final overrider, and not to an intermediate virtual base. */
2245 virtual_base = NULL_TREE;
2247 /* See if we can convert to an intermediate virtual base first, and then
2248 use the vcall offset located there to finish the conversion. */
2249 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2251 /* If we find the final overrider, then we can stop
2253 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2254 BINFO_TYPE (TREE_VALUE (overrider))))
2257 /* If we find a virtual base, and we haven't yet found the
2258 overrider, then there is a virtual base between the
2259 declaring base (first_defn) and the final overrider. */
2260 if (BINFO_VIRTUAL_P (b))
2267 /* Compute the constant adjustment to the `this' pointer. The
2268 `this' pointer, when this function is called, will point at BINFO
2269 (or one of its primary bases, which are at the same offset). */
2271 /* The `this' pointer needs to be adjusted from the declaration to
2272 the nearest virtual base. */
2273 delta = size_diffop_loc (input_location,
2274 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2275 convert (ssizetype, BINFO_OFFSET (first_defn)));
2277 /* If the nearest definition is in a lost primary, we don't need an
2278 entry in our vtable. Except possibly in a constructor vtable,
2279 if we happen to get our primary back. In that case, the offset
2280 will be zero, as it will be a primary base. */
2281 delta = size_zero_node;
2283 /* The `this' pointer needs to be adjusted from pointing to
2284 BINFO to pointing at the base where the final overrider
2286 delta = size_diffop_loc (input_location,
2288 BINFO_OFFSET (TREE_VALUE (overrider))),
2289 convert (ssizetype, BINFO_OFFSET (binfo)));
2291 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2294 BV_VCALL_INDEX (*virtuals)
2295 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2297 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2299 BV_LOST_PRIMARY (*virtuals) = lost;
2302 /* Called from modify_all_vtables via dfs_walk. */
2305 dfs_modify_vtables (tree binfo, void* data)
2307 tree t = (tree) data;
2312 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2313 /* A base without a vtable needs no modification, and its bases
2314 are uninteresting. */
2315 return dfs_skip_bases;
2317 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2318 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2319 /* Don't do the primary vtable, if it's new. */
2322 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2323 /* There's no need to modify the vtable for a non-virtual primary
2324 base; we're not going to use that vtable anyhow. We do still
2325 need to do this for virtual primary bases, as they could become
2326 non-primary in a construction vtable. */
2329 make_new_vtable (t, binfo);
2331 /* Now, go through each of the virtual functions in the virtual
2332 function table for BINFO. Find the final overrider, and update
2333 the BINFO_VIRTUALS list appropriately. */
2334 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2335 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2337 ix++, virtuals = TREE_CHAIN (virtuals),
2338 old_virtuals = TREE_CHAIN (old_virtuals))
2339 update_vtable_entry_for_fn (t,
2341 BV_FN (old_virtuals),
2347 /* Update all of the primary and secondary vtables for T. Create new
2348 vtables as required, and initialize their RTTI information. Each
2349 of the functions in VIRTUALS is declared in T and may override a
2350 virtual function from a base class; find and modify the appropriate
2351 entries to point to the overriding functions. Returns a list, in
2352 declaration order, of the virtual functions that are declared in T,
2353 but do not appear in the primary base class vtable, and which
2354 should therefore be appended to the end of the vtable for T. */
2357 modify_all_vtables (tree t, tree virtuals)
2359 tree binfo = TYPE_BINFO (t);
2362 /* Update all of the vtables. */
2363 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2365 /* Add virtual functions not already in our primary vtable. These
2366 will be both those introduced by this class, and those overridden
2367 from secondary bases. It does not include virtuals merely
2368 inherited from secondary bases. */
2369 for (fnsp = &virtuals; *fnsp; )
2371 tree fn = TREE_VALUE (*fnsp);
2373 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2374 || DECL_VINDEX (fn) == error_mark_node)
2376 /* We don't need to adjust the `this' pointer when
2377 calling this function. */
2378 BV_DELTA (*fnsp) = integer_zero_node;
2379 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2381 /* This is a function not already in our vtable. Keep it. */
2382 fnsp = &TREE_CHAIN (*fnsp);
2385 /* We've already got an entry for this function. Skip it. */
2386 *fnsp = TREE_CHAIN (*fnsp);
2392 /* Get the base virtual function declarations in T that have the
2396 get_basefndecls (tree name, tree t)
2399 tree base_fndecls = NULL_TREE;
2400 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2403 /* Find virtual functions in T with the indicated NAME. */
2404 i = lookup_fnfields_1 (t, name);
2406 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2408 methods = OVL_NEXT (methods))
2410 tree method = OVL_CURRENT (methods);
2412 if (TREE_CODE (method) == FUNCTION_DECL
2413 && DECL_VINDEX (method))
2414 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2418 return base_fndecls;
2420 for (i = 0; i < n_baseclasses; i++)
2422 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2423 base_fndecls = chainon (get_basefndecls (name, basetype),
2427 return base_fndecls;
2430 /* If this declaration supersedes the declaration of
2431 a method declared virtual in the base class, then
2432 mark this field as being virtual as well. */
2435 check_for_override (tree decl, tree ctype)
2437 bool overrides_found = false;
2438 if (TREE_CODE (decl) == TEMPLATE_DECL)
2439 /* In [temp.mem] we have:
2441 A specialization of a member function template does not
2442 override a virtual function from a base class. */
2444 if ((DECL_DESTRUCTOR_P (decl)
2445 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2446 || DECL_CONV_FN_P (decl))
2447 && look_for_overrides (ctype, decl)
2448 && !DECL_STATIC_FUNCTION_P (decl))
2449 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2450 the error_mark_node so that we know it is an overriding
2453 DECL_VINDEX (decl) = decl;
2454 overrides_found = true;
2457 if (DECL_VIRTUAL_P (decl))
2459 if (!DECL_VINDEX (decl))
2460 DECL_VINDEX (decl) = error_mark_node;
2461 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2462 if (DECL_DESTRUCTOR_P (decl))
2463 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (ctype) = true;
2465 else if (DECL_FINAL_P (decl))
2466 error ("%q+#D marked final, but is not virtual", decl);
2467 if (DECL_OVERRIDE_P (decl) && !overrides_found)
2468 error ("%q+#D marked override, but does not override", decl);
2471 /* Warn about hidden virtual functions that are not overridden in t.
2472 We know that constructors and destructors don't apply. */
2475 warn_hidden (tree t)
2477 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2481 /* We go through each separately named virtual function. */
2482 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2483 VEC_iterate (tree, method_vec, i, fns);
2494 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2495 have the same name. Figure out what name that is. */
2496 name = DECL_NAME (OVL_CURRENT (fns));
2497 /* There are no possibly hidden functions yet. */
2498 base_fndecls = NULL_TREE;
2499 /* Iterate through all of the base classes looking for possibly
2500 hidden functions. */
2501 for (binfo = TYPE_BINFO (t), j = 0;
2502 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2504 tree basetype = BINFO_TYPE (base_binfo);
2505 base_fndecls = chainon (get_basefndecls (name, basetype),
2509 /* If there are no functions to hide, continue. */
2513 /* Remove any overridden functions. */
2514 for (fn = fns; fn; fn = OVL_NEXT (fn))
2516 fndecl = OVL_CURRENT (fn);
2517 if (DECL_VINDEX (fndecl))
2519 tree *prev = &base_fndecls;
2522 /* If the method from the base class has the same
2523 signature as the method from the derived class, it
2524 has been overridden. */
2525 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2526 *prev = TREE_CHAIN (*prev);
2528 prev = &TREE_CHAIN (*prev);
2532 /* Now give a warning for all base functions without overriders,
2533 as they are hidden. */
2534 while (base_fndecls)
2536 /* Here we know it is a hider, and no overrider exists. */
2537 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2538 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2539 base_fndecls = TREE_CHAIN (base_fndecls);
2544 /* Check for things that are invalid. There are probably plenty of other
2545 things we should check for also. */
2548 finish_struct_anon (tree t)
2552 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
2554 if (TREE_STATIC (field))
2556 if (TREE_CODE (field) != FIELD_DECL)
2559 if (DECL_NAME (field) == NULL_TREE
2560 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2562 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2563 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2564 for (; elt; elt = DECL_CHAIN (elt))
2566 /* We're generally only interested in entities the user
2567 declared, but we also find nested classes by noticing
2568 the TYPE_DECL that we create implicitly. You're
2569 allowed to put one anonymous union inside another,
2570 though, so we explicitly tolerate that. We use
2571 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2572 we also allow unnamed types used for defining fields. */
2573 if (DECL_ARTIFICIAL (elt)
2574 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2575 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2578 if (TREE_CODE (elt) != FIELD_DECL)
2581 permerror (input_location, "%q+#D invalid; an anonymous union can "
2582 "only have non-static data members", elt);
2584 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2585 "only have non-static data members", elt);
2589 if (TREE_PRIVATE (elt))
2592 permerror (input_location, "private member %q+#D in anonymous union", elt);
2594 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2596 else if (TREE_PROTECTED (elt))
2599 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2601 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2604 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2605 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2611 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2612 will be used later during class template instantiation.
2613 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2614 a non-static member data (FIELD_DECL), a member function
2615 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2616 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2617 When FRIEND_P is nonzero, T is either a friend class
2618 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2619 (FUNCTION_DECL, TEMPLATE_DECL). */
2622 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2624 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2625 if (CLASSTYPE_TEMPLATE_INFO (type))
2626 CLASSTYPE_DECL_LIST (type)
2627 = tree_cons (friend_p ? NULL_TREE : type,
2628 t, CLASSTYPE_DECL_LIST (type));
2631 /* This function is called from declare_virt_assop_and_dtor via
2634 DATA is a type that direcly or indirectly inherits the base
2635 represented by BINFO. If BINFO contains a virtual assignment [copy
2636 assignment or move assigment] operator or a virtual constructor,
2637 declare that function in DATA if it hasn't been already declared. */
2640 dfs_declare_virt_assop_and_dtor (tree binfo, void *data)
2642 tree bv, fn, t = (tree)data;
2643 tree opname = ansi_assopname (NOP_EXPR);
2645 gcc_assert (t && CLASS_TYPE_P (t));
2646 gcc_assert (binfo && TREE_CODE (binfo) == TREE_BINFO);
2648 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2649 /* A base without a vtable needs no modification, and its bases
2650 are uninteresting. */
2651 return dfs_skip_bases;
2653 if (BINFO_PRIMARY_P (binfo))
2654 /* If this is a primary base, then we have already looked at the
2655 virtual functions of its vtable. */
2658 for (bv = BINFO_VIRTUALS (binfo); bv; bv = TREE_CHAIN (bv))
2662 if (DECL_NAME (fn) == opname)
2664 if (CLASSTYPE_LAZY_COPY_ASSIGN (t))
2665 lazily_declare_fn (sfk_copy_assignment, t);
2666 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
2667 lazily_declare_fn (sfk_move_assignment, t);
2669 else if (DECL_DESTRUCTOR_P (fn)
2670 && CLASSTYPE_LAZY_DESTRUCTOR (t))
2671 lazily_declare_fn (sfk_destructor, t);
2677 /* If the class type T has a direct or indirect base that contains a
2678 virtual assignment operator or a virtual destructor, declare that
2679 function in T if it hasn't been already declared. */
2682 declare_virt_assop_and_dtor (tree t)
2684 if (!(TYPE_POLYMORPHIC_P (t)
2685 && (CLASSTYPE_LAZY_COPY_ASSIGN (t)
2686 || CLASSTYPE_LAZY_MOVE_ASSIGN (t)
2687 || CLASSTYPE_LAZY_DESTRUCTOR (t))))
2690 dfs_walk_all (TYPE_BINFO (t),
2691 dfs_declare_virt_assop_and_dtor,
2695 /* Create default constructors, assignment operators, and so forth for
2696 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2697 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2698 the class cannot have a default constructor, copy constructor
2699 taking a const reference argument, or an assignment operator taking
2700 a const reference, respectively. */
2703 add_implicitly_declared_members (tree t,
2704 int cant_have_const_cctor,
2705 int cant_have_const_assignment)
2708 if (!CLASSTYPE_DESTRUCTORS (t))
2710 /* In general, we create destructors lazily. */
2711 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2713 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2714 && TYPE_FOR_JAVA (t))
2715 /* But if this is a Java class, any non-trivial destructor is
2716 invalid, even if compiler-generated. Therefore, if the
2717 destructor is non-trivial we create it now. */
2718 lazily_declare_fn (sfk_destructor, t);
2723 If there is no user-declared constructor for a class, a default
2724 constructor is implicitly declared. */
2725 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2727 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2728 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2729 if (cxx_dialect >= cxx0x)
2730 TYPE_HAS_CONSTEXPR_CTOR (t)
2731 /* This might force the declaration. */
2732 = type_has_constexpr_default_constructor (t);
2737 If a class definition does not explicitly declare a copy
2738 constructor, one is declared implicitly. */
2739 if (! TYPE_HAS_COPY_CTOR (t) && ! TYPE_FOR_JAVA (t)
2740 && !type_has_move_constructor (t))
2742 TYPE_HAS_COPY_CTOR (t) = 1;
2743 TYPE_HAS_CONST_COPY_CTOR (t) = !cant_have_const_cctor;
2744 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2745 if (cxx_dialect >= cxx0x)
2746 CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
2749 /* If there is no assignment operator, one will be created if and
2750 when it is needed. For now, just record whether or not the type
2751 of the parameter to the assignment operator will be a const or
2752 non-const reference. */
2753 if (!TYPE_HAS_COPY_ASSIGN (t) && !TYPE_FOR_JAVA (t)
2754 && !type_has_move_assign (t))
2756 TYPE_HAS_COPY_ASSIGN (t) = 1;
2757 TYPE_HAS_CONST_COPY_ASSIGN (t) = !cant_have_const_assignment;
2758 CLASSTYPE_LAZY_COPY_ASSIGN (t) = 1;
2759 if (cxx_dialect >= cxx0x)
2760 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 1;
2763 /* We can't be lazy about declaring functions that might override
2764 a virtual function from a base class. */
2765 declare_virt_assop_and_dtor (t);
2768 /* Subroutine of finish_struct_1. Recursively count the number of fields
2769 in TYPE, including anonymous union members. */
2772 count_fields (tree fields)
2776 for (x = fields; x; x = DECL_CHAIN (x))
2778 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2779 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2786 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2787 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2790 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2793 for (x = fields; x; x = DECL_CHAIN (x))
2795 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2796 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2798 field_vec->elts[idx++] = x;
2803 /* FIELD is a bit-field. We are finishing the processing for its
2804 enclosing type. Issue any appropriate messages and set appropriate
2805 flags. Returns false if an error has been diagnosed. */
2808 check_bitfield_decl (tree field)
2810 tree type = TREE_TYPE (field);
2813 /* Extract the declared width of the bitfield, which has been
2814 temporarily stashed in DECL_INITIAL. */
2815 w = DECL_INITIAL (field);
2816 gcc_assert (w != NULL_TREE);
2817 /* Remove the bit-field width indicator so that the rest of the
2818 compiler does not treat that value as an initializer. */
2819 DECL_INITIAL (field) = NULL_TREE;
2821 /* Detect invalid bit-field type. */
2822 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2824 error ("bit-field %q+#D with non-integral type", field);
2825 w = error_mark_node;
2829 location_t loc = input_location;
2830 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2833 /* detect invalid field size. */
2834 input_location = DECL_SOURCE_LOCATION (field);
2835 w = cxx_constant_value (w);
2836 input_location = loc;
2838 if (TREE_CODE (w) != INTEGER_CST)
2840 error ("bit-field %q+D width not an integer constant", field);
2841 w = error_mark_node;
2843 else if (tree_int_cst_sgn (w) < 0)
2845 error ("negative width in bit-field %q+D", field);
2846 w = error_mark_node;
2848 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2850 error ("zero width for bit-field %q+D", field);
2851 w = error_mark_node;
2853 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2854 && TREE_CODE (type) != ENUMERAL_TYPE
2855 && TREE_CODE (type) != BOOLEAN_TYPE)
2856 warning (0, "width of %q+D exceeds its type", field);
2857 else if (TREE_CODE (type) == ENUMERAL_TYPE
2858 && (0 > (compare_tree_int
2859 (w, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type))))))
2860 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2863 if (w != error_mark_node)
2865 DECL_SIZE (field) = convert (bitsizetype, w);
2866 DECL_BIT_FIELD (field) = 1;
2871 /* Non-bit-fields are aligned for their type. */
2872 DECL_BIT_FIELD (field) = 0;
2873 CLEAR_DECL_C_BIT_FIELD (field);
2878 /* FIELD is a non bit-field. We are finishing the processing for its
2879 enclosing type T. Issue any appropriate messages and set appropriate
2883 check_field_decl (tree field,
2885 int* cant_have_const_ctor,
2886 int* no_const_asn_ref,
2887 int* any_default_members)
2889 tree type = strip_array_types (TREE_TYPE (field));
2891 /* In C++98 an anonymous union cannot contain any fields which would change
2892 the settings of CANT_HAVE_CONST_CTOR and friends. */
2893 if (ANON_UNION_TYPE_P (type) && cxx_dialect < cxx0x)
2895 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2896 structs. So, we recurse through their fields here. */
2897 else if (ANON_AGGR_TYPE_P (type))
2901 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2902 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2903 check_field_decl (fields, t, cant_have_const_ctor,
2904 no_const_asn_ref, any_default_members);
2906 /* Check members with class type for constructors, destructors,
2908 else if (CLASS_TYPE_P (type))
2910 /* Never let anything with uninheritable virtuals
2911 make it through without complaint. */
2912 abstract_virtuals_error (field, type);
2914 if (TREE_CODE (t) == UNION_TYPE && cxx_dialect < cxx0x)
2917 int oldcount = errorcount;
2918 if (TYPE_NEEDS_CONSTRUCTING (type))
2919 error ("member %q+#D with constructor not allowed in union",
2921 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2922 error ("member %q+#D with destructor not allowed in union", field);
2923 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
2924 error ("member %q+#D with copy assignment operator not allowed in union",
2926 if (!warned && errorcount > oldcount)
2928 inform (DECL_SOURCE_LOCATION (field), "unrestricted unions "
2929 "only available with -std=c++0x or -std=gnu++0x");
2935 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2936 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2937 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2938 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
2939 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type)
2940 || !TYPE_HAS_COPY_ASSIGN (type));
2941 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type)
2942 || !TYPE_HAS_COPY_CTOR (type));
2943 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type);
2944 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type);
2945 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type)
2946 || TYPE_HAS_COMPLEX_DFLT (type));
2949 if (TYPE_HAS_COPY_CTOR (type)
2950 && !TYPE_HAS_CONST_COPY_CTOR (type))
2951 *cant_have_const_ctor = 1;
2953 if (TYPE_HAS_COPY_ASSIGN (type)
2954 && !TYPE_HAS_CONST_COPY_ASSIGN (type))
2955 *no_const_asn_ref = 1;
2957 if (DECL_INITIAL (field) != NULL_TREE)
2959 /* `build_class_init_list' does not recognize
2961 if (TREE_CODE (t) == UNION_TYPE && *any_default_members != 0)
2962 error ("multiple fields in union %qT initialized", t);
2963 *any_default_members = 1;
2967 /* Check the data members (both static and non-static), class-scoped
2968 typedefs, etc., appearing in the declaration of T. Issue
2969 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2970 declaration order) of access declarations; each TREE_VALUE in this
2971 list is a USING_DECL.
2973 In addition, set the following flags:
2976 The class is empty, i.e., contains no non-static data members.
2978 CANT_HAVE_CONST_CTOR_P
2979 This class cannot have an implicitly generated copy constructor
2980 taking a const reference.
2982 CANT_HAVE_CONST_ASN_REF
2983 This class cannot have an implicitly generated assignment
2984 operator taking a const reference.
2986 All of these flags should be initialized before calling this
2989 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2990 fields can be added by adding to this chain. */
2993 check_field_decls (tree t, tree *access_decls,
2994 int *cant_have_const_ctor_p,
2995 int *no_const_asn_ref_p)
3000 int any_default_members;
3002 int field_access = -1;
3004 /* Assume there are no access declarations. */
3005 *access_decls = NULL_TREE;
3006 /* Assume this class has no pointer members. */
3007 has_pointers = false;
3008 /* Assume none of the members of this class have default
3010 any_default_members = 0;
3012 for (field = &TYPE_FIELDS (t); *field; field = next)
3015 tree type = TREE_TYPE (x);
3016 int this_field_access;
3018 next = &DECL_CHAIN (x);
3020 if (TREE_CODE (x) == USING_DECL)
3022 /* Prune the access declaration from the list of fields. */
3023 *field = DECL_CHAIN (x);
3025 /* Save the access declarations for our caller. */
3026 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
3028 /* Since we've reset *FIELD there's no reason to skip to the
3034 if (TREE_CODE (x) == TYPE_DECL
3035 || TREE_CODE (x) == TEMPLATE_DECL)
3038 /* If we've gotten this far, it's a data member, possibly static,
3039 or an enumerator. */
3040 DECL_CONTEXT (x) = t;
3042 /* When this goes into scope, it will be a non-local reference. */
3043 DECL_NONLOCAL (x) = 1;
3045 if (TREE_CODE (t) == UNION_TYPE)
3049 If a union contains a static data member, or a member of
3050 reference type, the program is ill-formed. */
3051 if (TREE_CODE (x) == VAR_DECL)
3053 error ("%q+D may not be static because it is a member of a union", x);
3056 if (TREE_CODE (type) == REFERENCE_TYPE)
3058 error ("%q+D may not have reference type %qT because"
3059 " it is a member of a union",
3065 /* Perform error checking that did not get done in
3067 if (TREE_CODE (type) == FUNCTION_TYPE)
3069 error ("field %q+D invalidly declared function type", x);
3070 type = build_pointer_type (type);
3071 TREE_TYPE (x) = type;
3073 else if (TREE_CODE (type) == METHOD_TYPE)
3075 error ("field %q+D invalidly declared method type", x);
3076 type = build_pointer_type (type);
3077 TREE_TYPE (x) = type;
3080 if (type == error_mark_node)
3083 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
3086 /* Now it can only be a FIELD_DECL. */
3088 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3089 CLASSTYPE_NON_AGGREGATE (t) = 1;
3091 /* If at least one non-static data member is non-literal, the whole
3092 class becomes non-literal. */
3093 if (!literal_type_p (type))
3094 CLASSTYPE_LITERAL_P (t) = false;
3096 /* A standard-layout class is a class that:
3098 has the same access control (Clause 11) for all non-static data members,
3100 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3101 if (field_access == -1)
3102 field_access = this_field_access;
3103 else if (this_field_access != field_access)
3104 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3106 /* If this is of reference type, check if it needs an init. */
3107 if (TREE_CODE (type) == REFERENCE_TYPE)
3109 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3110 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3111 if (DECL_INITIAL (x) == NULL_TREE)
3112 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3114 /* ARM $12.6.2: [A member initializer list] (or, for an
3115 aggregate, initialization by a brace-enclosed list) is the
3116 only way to initialize nonstatic const and reference
3118 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3119 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3122 type = strip_array_types (type);
3124 if (TYPE_PACKED (t))
3126 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3130 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3134 else if (DECL_C_BIT_FIELD (x)
3135 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3136 DECL_PACKED (x) = 1;
3139 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3140 /* We don't treat zero-width bitfields as making a class
3145 /* The class is non-empty. */
3146 CLASSTYPE_EMPTY_P (t) = 0;
3147 /* The class is not even nearly empty. */
3148 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3149 /* If one of the data members contains an empty class,
3151 if (CLASS_TYPE_P (type)
3152 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3153 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3156 /* This is used by -Weffc++ (see below). Warn only for pointers
3157 to members which might hold dynamic memory. So do not warn
3158 for pointers to functions or pointers to members. */
3159 if (TYPE_PTR_P (type)
3160 && !TYPE_PTRFN_P (type)
3161 && !TYPE_PTR_TO_MEMBER_P (type))
3162 has_pointers = true;
3164 if (CLASS_TYPE_P (type))
3166 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3167 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3168 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3169 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3172 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3173 CLASSTYPE_HAS_MUTABLE (t) = 1;
3175 if (! layout_pod_type_p (type))
3176 /* DR 148 now allows pointers to members (which are POD themselves),
3177 to be allowed in POD structs. */
3178 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3180 if (!std_layout_type_p (type))
3181 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3183 if (! zero_init_p (type))
3184 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3186 /* We set DECL_C_BIT_FIELD in grokbitfield.
3187 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3188 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3189 check_field_decl (x, t,
3190 cant_have_const_ctor_p,
3192 &any_default_members);
3194 /* If any field is const, the structure type is pseudo-const. */
3195 if (CP_TYPE_CONST_P (type))
3197 C_TYPE_FIELDS_READONLY (t) = 1;
3198 if (DECL_INITIAL (x) == NULL_TREE)
3199 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3201 /* ARM $12.6.2: [A member initializer list] (or, for an
3202 aggregate, initialization by a brace-enclosed list) is the
3203 only way to initialize nonstatic const and reference
3205 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3206 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3208 /* A field that is pseudo-const makes the structure likewise. */
3209 else if (CLASS_TYPE_P (type))
3211 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3212 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3213 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3214 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3217 /* Core issue 80: A nonstatic data member is required to have a
3218 different name from the class iff the class has a
3219 user-declared constructor. */
3220 if (constructor_name_p (DECL_NAME (x), t)
3221 && TYPE_HAS_USER_CONSTRUCTOR (t))
3222 permerror (input_location, "field %q+#D with same name as class", x);
3225 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3226 it should also define a copy constructor and an assignment operator to
3227 implement the correct copy semantic (deep vs shallow, etc.). As it is
3228 not feasible to check whether the constructors do allocate dynamic memory
3229 and store it within members, we approximate the warning like this:
3231 -- Warn only if there are members which are pointers
3232 -- Warn only if there is a non-trivial constructor (otherwise,
3233 there cannot be memory allocated).
3234 -- Warn only if there is a non-trivial destructor. We assume that the
3235 user at least implemented the cleanup correctly, and a destructor
3236 is needed to free dynamic memory.
3238 This seems enough for practical purposes. */
3241 && TYPE_HAS_USER_CONSTRUCTOR (t)
3242 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3243 && !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
3245 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3247 if (! TYPE_HAS_COPY_CTOR (t))
3249 warning (OPT_Weffc__,
3250 " but does not override %<%T(const %T&)%>", t, t);
3251 if (!TYPE_HAS_COPY_ASSIGN (t))
3252 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3254 else if (! TYPE_HAS_COPY_ASSIGN (t))
3255 warning (OPT_Weffc__,
3256 " but does not override %<operator=(const %T&)%>", t);
3259 /* Non-static data member initializers make the default constructor
3261 if (any_default_members)
3263 TYPE_NEEDS_CONSTRUCTING (t) = true;
3264 TYPE_HAS_COMPLEX_DFLT (t) = true;
3267 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3269 TYPE_PACKED (t) = 0;
3271 /* Check anonymous struct/anonymous union fields. */
3272 finish_struct_anon (t);
3274 /* We've built up the list of access declarations in reverse order.
3276 *access_decls = nreverse (*access_decls);
3279 /* If TYPE is an empty class type, records its OFFSET in the table of
3283 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3287 if (!is_empty_class (type))
3290 /* Record the location of this empty object in OFFSETS. */
3291 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3293 n = splay_tree_insert (offsets,
3294 (splay_tree_key) offset,
3295 (splay_tree_value) NULL_TREE);
3296 n->value = ((splay_tree_value)
3297 tree_cons (NULL_TREE,
3304 /* Returns nonzero if TYPE is an empty class type and there is
3305 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3308 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3313 if (!is_empty_class (type))
3316 /* Record the location of this empty object in OFFSETS. */
3317 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3321 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3322 if (same_type_p (TREE_VALUE (t), type))
3328 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3329 F for every subobject, passing it the type, offset, and table of
3330 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3333 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3334 than MAX_OFFSET will not be walked.
3336 If F returns a nonzero value, the traversal ceases, and that value
3337 is returned. Otherwise, returns zero. */
3340 walk_subobject_offsets (tree type,
3341 subobject_offset_fn f,
3348 tree type_binfo = NULL_TREE;
3350 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3352 if (max_offset && INT_CST_LT (max_offset, offset))
3355 if (type == error_mark_node)
3360 if (abi_version_at_least (2))
3362 type = BINFO_TYPE (type);
3365 if (CLASS_TYPE_P (type))
3371 /* Avoid recursing into objects that are not interesting. */
3372 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3375 /* Record the location of TYPE. */
3376 r = (*f) (type, offset, offsets);
3380 /* Iterate through the direct base classes of TYPE. */
3382 type_binfo = TYPE_BINFO (type);
3383 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3387 if (abi_version_at_least (2)
3388 && BINFO_VIRTUAL_P (binfo))
3392 && BINFO_VIRTUAL_P (binfo)
3393 && !BINFO_PRIMARY_P (binfo))
3396 if (!abi_version_at_least (2))
3397 binfo_offset = size_binop (PLUS_EXPR,
3399 BINFO_OFFSET (binfo));
3403 /* We cannot rely on BINFO_OFFSET being set for the base
3404 class yet, but the offsets for direct non-virtual
3405 bases can be calculated by going back to the TYPE. */
3406 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3407 binfo_offset = size_binop (PLUS_EXPR,
3409 BINFO_OFFSET (orig_binfo));
3412 r = walk_subobject_offsets (binfo,
3417 (abi_version_at_least (2)
3418 ? /*vbases_p=*/0 : vbases_p));
3423 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3426 VEC(tree,gc) *vbases;
3428 /* Iterate through the virtual base classes of TYPE. In G++
3429 3.2, we included virtual bases in the direct base class
3430 loop above, which results in incorrect results; the
3431 correct offsets for virtual bases are only known when
3432 working with the most derived type. */
3434 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3435 VEC_iterate (tree, vbases, ix, binfo); ix++)
3437 r = walk_subobject_offsets (binfo,
3439 size_binop (PLUS_EXPR,
3441 BINFO_OFFSET (binfo)),
3450 /* We still have to walk the primary base, if it is
3451 virtual. (If it is non-virtual, then it was walked
3453 tree vbase = get_primary_binfo (type_binfo);
3455 if (vbase && BINFO_VIRTUAL_P (vbase)
3456 && BINFO_PRIMARY_P (vbase)
3457 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3459 r = (walk_subobject_offsets
3461 offsets, max_offset, /*vbases_p=*/0));
3468 /* Iterate through the fields of TYPE. */
3469 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
3470 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3474 if (abi_version_at_least (2))
3475 field_offset = byte_position (field);
3477 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3478 field_offset = DECL_FIELD_OFFSET (field);
3480 r = walk_subobject_offsets (TREE_TYPE (field),
3482 size_binop (PLUS_EXPR,
3492 else if (TREE_CODE (type) == ARRAY_TYPE)
3494 tree element_type = strip_array_types (type);
3495 tree domain = TYPE_DOMAIN (type);
3498 /* Avoid recursing into objects that are not interesting. */
3499 if (!CLASS_TYPE_P (element_type)
3500 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3503 /* Step through each of the elements in the array. */
3504 for (index = size_zero_node;
3505 /* G++ 3.2 had an off-by-one error here. */
3506 (abi_version_at_least (2)
3507 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3508 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3509 index = size_binop (PLUS_EXPR, index, size_one_node))
3511 r = walk_subobject_offsets (TREE_TYPE (type),
3519 offset = size_binop (PLUS_EXPR, offset,
3520 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3521 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3522 there's no point in iterating through the remaining
3523 elements of the array. */
3524 if (max_offset && INT_CST_LT (max_offset, offset))
3532 /* Record all of the empty subobjects of TYPE (either a type or a
3533 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3534 is being placed at OFFSET; otherwise, it is a base class that is
3535 being placed at OFFSET. */
3538 record_subobject_offsets (tree type,
3541 bool is_data_member)
3544 /* If recording subobjects for a non-static data member or a
3545 non-empty base class , we do not need to record offsets beyond
3546 the size of the biggest empty class. Additional data members
3547 will go at the end of the class. Additional base classes will go
3548 either at offset zero (if empty, in which case they cannot
3549 overlap with offsets past the size of the biggest empty class) or
3550 at the end of the class.
3552 However, if we are placing an empty base class, then we must record
3553 all offsets, as either the empty class is at offset zero (where
3554 other empty classes might later be placed) or at the end of the
3555 class (where other objects might then be placed, so other empty
3556 subobjects might later overlap). */
3558 || !is_empty_class (BINFO_TYPE (type)))
3559 max_offset = sizeof_biggest_empty_class;
3561 max_offset = NULL_TREE;
3562 walk_subobject_offsets (type, record_subobject_offset, offset,
3563 offsets, max_offset, is_data_member);
3566 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3567 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3568 virtual bases of TYPE are examined. */
3571 layout_conflict_p (tree type,
3576 splay_tree_node max_node;
3578 /* Get the node in OFFSETS that indicates the maximum offset where
3579 an empty subobject is located. */
3580 max_node = splay_tree_max (offsets);
3581 /* If there aren't any empty subobjects, then there's no point in
3582 performing this check. */
3586 return walk_subobject_offsets (type, check_subobject_offset, offset,
3587 offsets, (tree) (max_node->key),
3591 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3592 non-static data member of the type indicated by RLI. BINFO is the
3593 binfo corresponding to the base subobject, OFFSETS maps offsets to
3594 types already located at those offsets. This function determines
3595 the position of the DECL. */
3598 layout_nonempty_base_or_field (record_layout_info rli,
3603 tree offset = NULL_TREE;
3609 /* For the purposes of determining layout conflicts, we want to
3610 use the class type of BINFO; TREE_TYPE (DECL) will be the
3611 CLASSTYPE_AS_BASE version, which does not contain entries for
3612 zero-sized bases. */
3613 type = TREE_TYPE (binfo);
3618 type = TREE_TYPE (decl);
3622 /* Try to place the field. It may take more than one try if we have
3623 a hard time placing the field without putting two objects of the
3624 same type at the same address. */
3627 struct record_layout_info_s old_rli = *rli;
3629 /* Place this field. */
3630 place_field (rli, decl);
3631 offset = byte_position (decl);
3633 /* We have to check to see whether or not there is already
3634 something of the same type at the offset we're about to use.
3635 For example, consider:
3638 struct T : public S { int i; };
3639 struct U : public S, public T {};
3641 Here, we put S at offset zero in U. Then, we can't put T at
3642 offset zero -- its S component would be at the same address
3643 as the S we already allocated. So, we have to skip ahead.
3644 Since all data members, including those whose type is an
3645 empty class, have nonzero size, any overlap can happen only
3646 with a direct or indirect base-class -- it can't happen with
3648 /* In a union, overlap is permitted; all members are placed at
3650 if (TREE_CODE (rli->t) == UNION_TYPE)
3652 /* G++ 3.2 did not check for overlaps when placing a non-empty
3654 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3656 if (layout_conflict_p (field_p ? type : binfo, offset,
3659 /* Strip off the size allocated to this field. That puts us
3660 at the first place we could have put the field with
3661 proper alignment. */
3664 /* Bump up by the alignment required for the type. */
3666 = size_binop (PLUS_EXPR, rli->bitpos,
3668 ? CLASSTYPE_ALIGN (type)
3669 : TYPE_ALIGN (type)));
3670 normalize_rli (rli);
3673 /* There was no conflict. We're done laying out this field. */
3677 /* Now that we know where it will be placed, update its
3679 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3680 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3681 this point because their BINFO_OFFSET is copied from another
3682 hierarchy. Therefore, we may not need to add the entire
3684 propagate_binfo_offsets (binfo,
3685 size_diffop_loc (input_location,
3686 convert (ssizetype, offset),
3688 BINFO_OFFSET (binfo))));
3691 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3694 empty_base_at_nonzero_offset_p (tree type,
3696 splay_tree offsets ATTRIBUTE_UNUSED)
3698 return is_empty_class (type) && !integer_zerop (offset);
3701 /* Layout the empty base BINFO. EOC indicates the byte currently just
3702 past the end of the class, and should be correctly aligned for a
3703 class of the type indicated by BINFO; OFFSETS gives the offsets of
3704 the empty bases allocated so far. T is the most derived
3705 type. Return nonzero iff we added it at the end. */
3708 layout_empty_base (record_layout_info rli, tree binfo,
3709 tree eoc, splay_tree offsets)
3712 tree basetype = BINFO_TYPE (binfo);
3715 /* This routine should only be used for empty classes. */
3716 gcc_assert (is_empty_class (basetype));
3717 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3719 if (!integer_zerop (BINFO_OFFSET (binfo)))
3721 if (abi_version_at_least (2))
3722 propagate_binfo_offsets
3723 (binfo, size_diffop_loc (input_location,
3724 size_zero_node, BINFO_OFFSET (binfo)));
3727 "offset of empty base %qT may not be ABI-compliant and may"
3728 "change in a future version of GCC",
3729 BINFO_TYPE (binfo));
3732 /* This is an empty base class. We first try to put it at offset
3734 if (layout_conflict_p (binfo,
3735 BINFO_OFFSET (binfo),
3739 /* That didn't work. Now, we move forward from the next
3740 available spot in the class. */
3742 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3745 if (!layout_conflict_p (binfo,
3746 BINFO_OFFSET (binfo),
3749 /* We finally found a spot where there's no overlap. */
3752 /* There's overlap here, too. Bump along to the next spot. */
3753 propagate_binfo_offsets (binfo, alignment);
3757 if (CLASSTYPE_USER_ALIGN (basetype))
3759 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3761 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3762 TYPE_USER_ALIGN (rli->t) = 1;
3768 /* Layout the base given by BINFO in the class indicated by RLI.
3769 *BASE_ALIGN is a running maximum of the alignments of
3770 any base class. OFFSETS gives the location of empty base
3771 subobjects. T is the most derived type. Return nonzero if the new
3772 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3773 *NEXT_FIELD, unless BINFO is for an empty base class.
3775 Returns the location at which the next field should be inserted. */
3778 build_base_field (record_layout_info rli, tree binfo,
3779 splay_tree offsets, tree *next_field)
3782 tree basetype = BINFO_TYPE (binfo);
3784 if (!COMPLETE_TYPE_P (basetype))
3785 /* This error is now reported in xref_tag, thus giving better
3786 location information. */
3789 /* Place the base class. */
3790 if (!is_empty_class (basetype))
3794 /* The containing class is non-empty because it has a non-empty
3796 CLASSTYPE_EMPTY_P (t) = 0;
3798 /* Create the FIELD_DECL. */
3799 decl = build_decl (input_location,
3800 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3801 DECL_ARTIFICIAL (decl) = 1;
3802 DECL_IGNORED_P (decl) = 1;
3803 DECL_FIELD_CONTEXT (decl) = t;
3804 if (CLASSTYPE_AS_BASE (basetype))
3806 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3807 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3808 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3809 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3810 DECL_MODE (decl) = TYPE_MODE (basetype);
3811 DECL_FIELD_IS_BASE (decl) = 1;
3813 /* Try to place the field. It may take more than one try if we
3814 have a hard time placing the field without putting two
3815 objects of the same type at the same address. */
3816 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3817 /* Add the new FIELD_DECL to the list of fields for T. */
3818 DECL_CHAIN (decl) = *next_field;
3820 next_field = &DECL_CHAIN (decl);
3828 /* On some platforms (ARM), even empty classes will not be
3830 eoc = round_up_loc (input_location,
3831 rli_size_unit_so_far (rli),
3832 CLASSTYPE_ALIGN_UNIT (basetype));
3833 atend = layout_empty_base (rli, binfo, eoc, offsets);
3834 /* A nearly-empty class "has no proper base class that is empty,
3835 not morally virtual, and at an offset other than zero." */
3836 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3839 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3840 /* The check above (used in G++ 3.2) is insufficient because
3841 an empty class placed at offset zero might itself have an
3842 empty base at a nonzero offset. */
3843 else if (walk_subobject_offsets (basetype,
3844 empty_base_at_nonzero_offset_p,
3847 /*max_offset=*/NULL_TREE,
3850 if (abi_version_at_least (2))
3851 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3854 "class %qT will be considered nearly empty in a "
3855 "future version of GCC", t);
3859 /* We do not create a FIELD_DECL for empty base classes because
3860 it might overlap some other field. We want to be able to
3861 create CONSTRUCTORs for the class by iterating over the
3862 FIELD_DECLs, and the back end does not handle overlapping
3865 /* An empty virtual base causes a class to be non-empty
3866 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3867 here because that was already done when the virtual table
3868 pointer was created. */
3871 /* Record the offsets of BINFO and its base subobjects. */
3872 record_subobject_offsets (binfo,
3873 BINFO_OFFSET (binfo),
3875 /*is_data_member=*/false);
3880 /* Layout all of the non-virtual base classes. Record empty
3881 subobjects in OFFSETS. T is the most derived type. Return nonzero
3882 if the type cannot be nearly empty. The fields created
3883 corresponding to the base classes will be inserted at
3887 build_base_fields (record_layout_info rli,
3888 splay_tree offsets, tree *next_field)
3890 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3893 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3896 /* The primary base class is always allocated first. */
3897 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3898 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3899 offsets, next_field);
3901 /* Now allocate the rest of the bases. */
3902 for (i = 0; i < n_baseclasses; ++i)
3906 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3908 /* The primary base was already allocated above, so we don't
3909 need to allocate it again here. */
3910 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3913 /* Virtual bases are added at the end (a primary virtual base
3914 will have already been added). */
3915 if (BINFO_VIRTUAL_P (base_binfo))
3918 next_field = build_base_field (rli, base_binfo,
3919 offsets, next_field);
3923 /* Go through the TYPE_METHODS of T issuing any appropriate
3924 diagnostics, figuring out which methods override which other
3925 methods, and so forth. */
3928 check_methods (tree t)
3932 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
3934 check_for_override (x, t);
3935 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3936 error ("initializer specified for non-virtual method %q+D", x);
3937 /* The name of the field is the original field name
3938 Save this in auxiliary field for later overloading. */
3939 if (DECL_VINDEX (x))
3941 TYPE_POLYMORPHIC_P (t) = 1;
3942 if (DECL_PURE_VIRTUAL_P (x))
3943 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3945 /* All user-provided destructors are non-trivial.
3946 Constructors and assignment ops are handled in
3947 grok_special_member_properties. */
3948 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
3949 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3953 /* FN is a constructor or destructor. Clone the declaration to create
3954 a specialized in-charge or not-in-charge version, as indicated by
3958 build_clone (tree fn, tree name)
3963 /* Copy the function. */
3964 clone = copy_decl (fn);
3965 /* Reset the function name. */
3966 DECL_NAME (clone) = name;
3967 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3968 /* Remember where this function came from. */
3969 DECL_ABSTRACT_ORIGIN (clone) = fn;
3970 /* Make it easy to find the CLONE given the FN. */
3971 DECL_CHAIN (clone) = DECL_CHAIN (fn);
3972 DECL_CHAIN (fn) = clone;
3974 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3975 if (TREE_CODE (clone) == TEMPLATE_DECL)
3977 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3978 DECL_TEMPLATE_RESULT (clone) = result;
3979 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3980 DECL_TI_TEMPLATE (result) = clone;
3981 TREE_TYPE (clone) = TREE_TYPE (result);
3985 DECL_CLONED_FUNCTION (clone) = fn;
3986 /* There's no pending inline data for this function. */
3987 DECL_PENDING_INLINE_INFO (clone) = NULL;
3988 DECL_PENDING_INLINE_P (clone) = 0;
3990 /* The base-class destructor is not virtual. */
3991 if (name == base_dtor_identifier)
3993 DECL_VIRTUAL_P (clone) = 0;
3994 if (TREE_CODE (clone) != TEMPLATE_DECL)
3995 DECL_VINDEX (clone) = NULL_TREE;
3998 /* If there was an in-charge parameter, drop it from the function
4000 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4006 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4007 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4008 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
4009 /* Skip the `this' parameter. */
4010 parmtypes = TREE_CHAIN (parmtypes);
4011 /* Skip the in-charge parameter. */
4012 parmtypes = TREE_CHAIN (parmtypes);
4013 /* And the VTT parm, in a complete [cd]tor. */
4014 if (DECL_HAS_VTT_PARM_P (fn)
4015 && ! DECL_NEEDS_VTT_PARM_P (clone))
4016 parmtypes = TREE_CHAIN (parmtypes);
4017 /* If this is subobject constructor or destructor, add the vtt
4020 = build_method_type_directly (basetype,
4021 TREE_TYPE (TREE_TYPE (clone)),
4024 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
4027 = cp_build_type_attribute_variant (TREE_TYPE (clone),
4028 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
4031 /* Copy the function parameters. */
4032 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
4033 /* Remove the in-charge parameter. */
4034 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4036 DECL_CHAIN (DECL_ARGUMENTS (clone))
4037 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4038 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
4040 /* And the VTT parm, in a complete [cd]tor. */
4041 if (DECL_HAS_VTT_PARM_P (fn))
4043 if (DECL_NEEDS_VTT_PARM_P (clone))
4044 DECL_HAS_VTT_PARM_P (clone) = 1;
4047 DECL_CHAIN (DECL_ARGUMENTS (clone))
4048 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4049 DECL_HAS_VTT_PARM_P (clone) = 0;
4053 for (parms = DECL_ARGUMENTS (clone); parms; parms = DECL_CHAIN (parms))
4055 DECL_CONTEXT (parms) = clone;
4056 cxx_dup_lang_specific_decl (parms);
4059 /* Create the RTL for this function. */
4060 SET_DECL_RTL (clone, NULL);
4061 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
4064 note_decl_for_pch (clone);
4069 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4070 not invoke this function directly.
4072 For a non-thunk function, returns the address of the slot for storing
4073 the function it is a clone of. Otherwise returns NULL_TREE.
4075 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4076 cloned_function is unset. This is to support the separate
4077 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4078 on a template makes sense, but not the former. */
4081 decl_cloned_function_p (const_tree decl, bool just_testing)
4085 decl = STRIP_TEMPLATE (decl);
4087 if (TREE_CODE (decl) != FUNCTION_DECL
4088 || !DECL_LANG_SPECIFIC (decl)
4089 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
4091 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4093 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
4099 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
4100 if (just_testing && *ptr == NULL_TREE)
4106 /* Produce declarations for all appropriate clones of FN. If
4107 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4108 CLASTYPE_METHOD_VEC as well. */
4111 clone_function_decl (tree fn, int update_method_vec_p)
4115 /* Avoid inappropriate cloning. */
4117 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (fn)))
4120 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4122 /* For each constructor, we need two variants: an in-charge version
4123 and a not-in-charge version. */
4124 clone = build_clone (fn, complete_ctor_identifier);
4125 if (update_method_vec_p)
4126 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4127 clone = build_clone (fn, base_ctor_identifier);
4128 if (update_method_vec_p)
4129 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4133 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4135 /* For each destructor, we need three variants: an in-charge
4136 version, a not-in-charge version, and an in-charge deleting
4137 version. We clone the deleting version first because that
4138 means it will go second on the TYPE_METHODS list -- and that
4139 corresponds to the correct layout order in the virtual
4142 For a non-virtual destructor, we do not build a deleting
4144 if (DECL_VIRTUAL_P (fn))
4146 clone = build_clone (fn, deleting_dtor_identifier);
4147 if (update_method_vec_p)
4148 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4150 clone = build_clone (fn, complete_dtor_identifier);
4151 if (update_method_vec_p)
4152 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4153 clone = build_clone (fn, base_dtor_identifier);
4154 if (update_method_vec_p)
4155 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4158 /* Note that this is an abstract function that is never emitted. */
4159 DECL_ABSTRACT (fn) = 1;
4162 /* DECL is an in charge constructor, which is being defined. This will
4163 have had an in class declaration, from whence clones were
4164 declared. An out-of-class definition can specify additional default
4165 arguments. As it is the clones that are involved in overload
4166 resolution, we must propagate the information from the DECL to its
4170 adjust_clone_args (tree decl)
4174 for (clone = DECL_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4175 clone = DECL_CHAIN (clone))
4177 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4178 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4179 tree decl_parms, clone_parms;
4181 clone_parms = orig_clone_parms;
4183 /* Skip the 'this' parameter. */
4184 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4185 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4187 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4188 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4189 if (DECL_HAS_VTT_PARM_P (decl))
4190 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4192 clone_parms = orig_clone_parms;
4193 if (DECL_HAS_VTT_PARM_P (clone))
4194 clone_parms = TREE_CHAIN (clone_parms);
4196 for (decl_parms = orig_decl_parms; decl_parms;
4197 decl_parms = TREE_CHAIN (decl_parms),
4198 clone_parms = TREE_CHAIN (clone_parms))
4200 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4201 TREE_TYPE (clone_parms)));
4203 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4205 /* A default parameter has been added. Adjust the
4206 clone's parameters. */
4207 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4208 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4209 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4212 clone_parms = orig_decl_parms;
4214 if (DECL_HAS_VTT_PARM_P (clone))
4216 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4217 TREE_VALUE (orig_clone_parms),
4219 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4221 type = build_method_type_directly (basetype,
4222 TREE_TYPE (TREE_TYPE (clone)),
4225 type = build_exception_variant (type, exceptions);
4227 type = cp_build_type_attribute_variant (type, attrs);
4228 TREE_TYPE (clone) = type;
4230 clone_parms = NULL_TREE;
4234 gcc_assert (!clone_parms);
4238 /* For each of the constructors and destructors in T, create an
4239 in-charge and not-in-charge variant. */
4242 clone_constructors_and_destructors (tree t)
4246 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4248 if (!CLASSTYPE_METHOD_VEC (t))
4251 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4252 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4253 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4254 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4257 /* Returns true iff class T has a user-defined constructor other than
4258 the default constructor. */
4261 type_has_user_nondefault_constructor (tree t)
4265 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4268 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4270 tree fn = OVL_CURRENT (fns);
4271 if (!DECL_ARTIFICIAL (fn)
4272 && (TREE_CODE (fn) == TEMPLATE_DECL
4273 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4281 /* Returns the defaulted constructor if T has one. Otherwise, returns
4285 in_class_defaulted_default_constructor (tree t)
4289 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4292 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4294 tree fn = OVL_CURRENT (fns);
4296 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4298 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4299 while (args && TREE_PURPOSE (args))
4300 args = TREE_CHAIN (args);
4301 if (!args || args == void_list_node)
4309 /* Returns true iff FN is a user-provided function, i.e. user-declared
4310 and not defaulted at its first declaration; or explicit, private,
4311 protected, or non-const. */
4314 user_provided_p (tree fn)
4316 if (TREE_CODE (fn) == TEMPLATE_DECL)
4319 return (!DECL_ARTIFICIAL (fn)
4320 && !DECL_DEFAULTED_IN_CLASS_P (fn));
4323 /* Returns true iff class T has a user-provided constructor. */
4326 type_has_user_provided_constructor (tree t)
4330 if (!CLASS_TYPE_P (t))
4333 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4336 /* This can happen in error cases; avoid crashing. */
4337 if (!CLASSTYPE_METHOD_VEC (t))
4340 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4341 if (user_provided_p (OVL_CURRENT (fns)))
4347 /* Returns true iff class T has a user-provided default constructor. */
4350 type_has_user_provided_default_constructor (tree t)
4354 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4357 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4359 tree fn = OVL_CURRENT (fns);
4360 if (TREE_CODE (fn) == FUNCTION_DECL
4361 && user_provided_p (fn)
4362 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)))
4369 /* If default-initialization leaves part of TYPE uninitialized, returns
4370 a DECL for the field or TYPE itself (DR 253). */
4373 default_init_uninitialized_part (tree type)
4378 type = strip_array_types (type);
4379 if (!CLASS_TYPE_P (type))
4381 if (type_has_user_provided_default_constructor (type))
4383 for (binfo = TYPE_BINFO (type), i = 0;
4384 BINFO_BASE_ITERATE (binfo, i, t); ++i)
4386 r = default_init_uninitialized_part (BINFO_TYPE (t));
4390 for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t))
4391 if (TREE_CODE (t) == FIELD_DECL
4392 && !DECL_ARTIFICIAL (t)
4393 && !DECL_INITIAL (t))
4395 r = default_init_uninitialized_part (TREE_TYPE (t));
4397 return DECL_P (r) ? r : t;
4403 /* Returns true iff for class T, a trivial synthesized default constructor
4404 would be constexpr. */
4407 trivial_default_constructor_is_constexpr (tree t)
4409 /* A defaulted trivial default constructor is constexpr
4410 if there is nothing to initialize. */
4411 gcc_assert (!TYPE_HAS_COMPLEX_DFLT (t));
4412 return is_really_empty_class (t);
4415 /* Returns true iff class T has a constexpr default constructor. */
4418 type_has_constexpr_default_constructor (tree t)
4422 if (!CLASS_TYPE_P (t))
4424 /* The caller should have stripped an enclosing array. */
4425 gcc_assert (TREE_CODE (t) != ARRAY_TYPE);
4428 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t))
4430 if (!TYPE_HAS_COMPLEX_DFLT (t))
4431 return trivial_default_constructor_is_constexpr (t);
4432 /* Non-trivial, we need to check subobject constructors. */
4433 lazily_declare_fn (sfk_constructor, t);
4435 fns = locate_ctor (t);
4436 return (fns && DECL_DECLARED_CONSTEXPR_P (fns));
4439 /* Returns true iff class TYPE has a virtual destructor. */
4442 type_has_virtual_destructor (tree type)
4446 if (!CLASS_TYPE_P (type))
4449 gcc_assert (COMPLETE_TYPE_P (type));
4450 dtor = CLASSTYPE_DESTRUCTORS (type);
4451 return (dtor && DECL_VIRTUAL_P (dtor));
4454 /* Returns true iff class T has a move constructor. */
4457 type_has_move_constructor (tree t)
4461 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4463 gcc_assert (COMPLETE_TYPE_P (t));
4464 lazily_declare_fn (sfk_move_constructor, t);
4467 if (!CLASSTYPE_METHOD_VEC (t))
4470 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4471 if (move_fn_p (OVL_CURRENT (fns)))
4477 /* Returns true iff class T has a move assignment operator. */
4480 type_has_move_assign (tree t)
4484 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4486 gcc_assert (COMPLETE_TYPE_P (t));
4487 lazily_declare_fn (sfk_move_assignment, t);
4490 for (fns = lookup_fnfields_slot (t, ansi_assopname (NOP_EXPR));
4491 fns; fns = OVL_NEXT (fns))
4492 if (move_fn_p (OVL_CURRENT (fns)))
4498 /* Nonzero if we need to build up a constructor call when initializing an
4499 object of this class, either because it has a user-provided constructor
4500 or because it doesn't have a default constructor (so we need to give an
4501 error if no initializer is provided). Use TYPE_NEEDS_CONSTRUCTING when
4502 what you care about is whether or not an object can be produced by a
4503 constructor (e.g. so we don't set TREE_READONLY on const variables of
4504 such type); use this function when what you care about is whether or not
4505 to try to call a constructor to create an object. The latter case is
4506 the former plus some cases of constructors that cannot be called. */
4509 type_build_ctor_call (tree t)
4512 if (TYPE_NEEDS_CONSTRUCTING (t))
4514 inner = strip_array_types (t);
4515 return (CLASS_TYPE_P (inner) && !TYPE_HAS_DEFAULT_CONSTRUCTOR (inner)
4516 && !ANON_AGGR_TYPE_P (inner));
4519 /* Remove all zero-width bit-fields from T. */
4522 remove_zero_width_bit_fields (tree t)
4526 fieldsp = &TYPE_FIELDS (t);
4529 if (TREE_CODE (*fieldsp) == FIELD_DECL
4530 && DECL_C_BIT_FIELD (*fieldsp)
4531 /* We should not be confused by the fact that grokbitfield
4532 temporarily sets the width of the bit field into
4533 DECL_INITIAL (*fieldsp).
4534 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4536 && integer_zerop (DECL_SIZE (*fieldsp)))
4537 *fieldsp = DECL_CHAIN (*fieldsp);
4539 fieldsp = &DECL_CHAIN (*fieldsp);
4543 /* Returns TRUE iff we need a cookie when dynamically allocating an
4544 array whose elements have the indicated class TYPE. */
4547 type_requires_array_cookie (tree type)
4550 bool has_two_argument_delete_p = false;
4552 gcc_assert (CLASS_TYPE_P (type));
4554 /* If there's a non-trivial destructor, we need a cookie. In order
4555 to iterate through the array calling the destructor for each
4556 element, we'll have to know how many elements there are. */
4557 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4560 /* If the usual deallocation function is a two-argument whose second
4561 argument is of type `size_t', then we have to pass the size of
4562 the array to the deallocation function, so we will need to store
4564 fns = lookup_fnfields (TYPE_BINFO (type),
4565 ansi_opname (VEC_DELETE_EXPR),
4567 /* If there are no `operator []' members, or the lookup is
4568 ambiguous, then we don't need a cookie. */
4569 if (!fns || fns == error_mark_node)
4571 /* Loop through all of the functions. */
4572 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4577 /* Select the current function. */
4578 fn = OVL_CURRENT (fns);
4579 /* See if this function is a one-argument delete function. If
4580 it is, then it will be the usual deallocation function. */
4581 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4582 if (second_parm == void_list_node)
4584 /* Do not consider this function if its second argument is an
4588 /* Otherwise, if we have a two-argument function and the second
4589 argument is `size_t', it will be the usual deallocation
4590 function -- unless there is one-argument function, too. */
4591 if (TREE_CHAIN (second_parm) == void_list_node
4592 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4593 has_two_argument_delete_p = true;
4596 return has_two_argument_delete_p;
4599 /* Finish computing the `literal type' property of class type T.
4601 At this point, we have already processed base classes and
4602 non-static data members. We need to check whether the copy
4603 constructor is trivial, the destructor is trivial, and there
4604 is a trivial default constructor or at least one constexpr
4605 constructor other than the copy constructor. */
4608 finalize_literal_type_property (tree t)
4612 if (cxx_dialect < cxx0x
4613 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
4614 CLASSTYPE_LITERAL_P (t) = false;
4615 else if (CLASSTYPE_LITERAL_P (t) && !TYPE_HAS_TRIVIAL_DFLT (t)
4616 && CLASSTYPE_NON_AGGREGATE (t)
4617 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4618 CLASSTYPE_LITERAL_P (t) = false;
4620 if (!CLASSTYPE_LITERAL_P (t))
4621 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4622 if (DECL_DECLARED_CONSTEXPR_P (fn)
4623 && TREE_CODE (fn) != TEMPLATE_DECL
4624 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
4625 && !DECL_CONSTRUCTOR_P (fn))
4627 DECL_DECLARED_CONSTEXPR_P (fn) = false;
4628 if (!DECL_GENERATED_P (fn))
4630 error ("enclosing class of constexpr non-static member "
4631 "function %q+#D is not a literal type", fn);
4632 explain_non_literal_class (t);
4637 /* T is a non-literal type used in a context which requires a constant
4638 expression. Explain why it isn't literal. */
4641 explain_non_literal_class (tree t)
4643 static struct pointer_set_t *diagnosed;
4645 if (!CLASS_TYPE_P (t))
4647 t = TYPE_MAIN_VARIANT (t);
4649 if (diagnosed == NULL)
4650 diagnosed = pointer_set_create ();
4651 if (pointer_set_insert (diagnosed, t) != 0)
4652 /* Already explained. */
4655 inform (0, "%q+T is not literal because:", t);
4656 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
4657 inform (0, " %q+T has a non-trivial destructor", t);
4658 else if (CLASSTYPE_NON_AGGREGATE (t)
4659 && !TYPE_HAS_TRIVIAL_DFLT (t)
4660 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4662 inform (0, " %q+T is not an aggregate, does not have a trivial "
4663 "default constructor, and has no constexpr constructor that "
4664 "is not a copy or move constructor", t);
4665 if (TYPE_HAS_DEFAULT_CONSTRUCTOR (t)
4666 && !type_has_user_provided_default_constructor (t))
4667 explain_invalid_constexpr_fn (locate_ctor (t));
4671 tree binfo, base_binfo, field; int i;
4672 for (binfo = TYPE_BINFO (t), i = 0;
4673 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
4675 tree basetype = TREE_TYPE (base_binfo);
4676 if (!CLASSTYPE_LITERAL_P (basetype))
4678 inform (0, " base class %qT of %q+T is non-literal",
4680 explain_non_literal_class (basetype);
4684 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4687 if (TREE_CODE (field) != FIELD_DECL)
4689 ftype = TREE_TYPE (field);
4690 if (!literal_type_p (ftype))
4692 inform (0, " non-static data member %q+D has "
4693 "non-literal type", field);
4694 if (CLASS_TYPE_P (ftype))
4695 explain_non_literal_class (ftype);
4701 /* Check the validity of the bases and members declared in T. Add any
4702 implicitly-generated functions (like copy-constructors and
4703 assignment operators). Compute various flag bits (like
4704 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4705 level: i.e., independently of the ABI in use. */
4708 check_bases_and_members (tree t)
4710 /* Nonzero if the implicitly generated copy constructor should take
4711 a non-const reference argument. */
4712 int cant_have_const_ctor;
4713 /* Nonzero if the implicitly generated assignment operator
4714 should take a non-const reference argument. */
4715 int no_const_asn_ref;
4717 bool saved_complex_asn_ref;
4718 bool saved_nontrivial_dtor;
4721 /* By default, we use const reference arguments and generate default
4723 cant_have_const_ctor = 0;
4724 no_const_asn_ref = 0;
4726 /* Check all the base-classes. */
4727 check_bases (t, &cant_have_const_ctor,
4730 /* Check all the method declarations. */
4733 /* Save the initial values of these flags which only indicate whether
4734 or not the class has user-provided functions. As we analyze the
4735 bases and members we can set these flags for other reasons. */
4736 saved_complex_asn_ref = TYPE_HAS_COMPLEX_COPY_ASSIGN (t);
4737 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4739 /* Check all the data member declarations. We cannot call
4740 check_field_decls until we have called check_bases check_methods,
4741 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4742 being set appropriately. */
4743 check_field_decls (t, &access_decls,
4744 &cant_have_const_ctor,
4747 /* A nearly-empty class has to be vptr-containing; a nearly empty
4748 class contains just a vptr. */
4749 if (!TYPE_CONTAINS_VPTR_P (t))
4750 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4752 /* Do some bookkeeping that will guide the generation of implicitly
4753 declared member functions. */
4754 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4755 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4756 /* We need to call a constructor for this class if it has a
4757 user-provided constructor, or if the default constructor is going
4758 to initialize the vptr. (This is not an if-and-only-if;
4759 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4760 themselves need constructing.) */
4761 TYPE_NEEDS_CONSTRUCTING (t)
4762 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4765 An aggregate is an array or a class with no user-provided
4766 constructors ... and no virtual functions.
4768 Again, other conditions for being an aggregate are checked
4770 CLASSTYPE_NON_AGGREGATE (t)
4771 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4772 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4773 retain the old definition internally for ABI reasons. */
4774 CLASSTYPE_NON_LAYOUT_POD_P (t)
4775 |= (CLASSTYPE_NON_AGGREGATE (t)
4776 || saved_nontrivial_dtor || saved_complex_asn_ref);
4777 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
4778 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4779 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4780 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4782 /* If the class has no user-declared constructor, but does have
4783 non-static const or reference data members that can never be
4784 initialized, issue a warning. */
4785 if (warn_uninitialized
4786 /* Classes with user-declared constructors are presumed to
4787 initialize these members. */
4788 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4789 /* Aggregates can be initialized with brace-enclosed
4791 && CLASSTYPE_NON_AGGREGATE (t))
4795 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
4799 if (TREE_CODE (field) != FIELD_DECL)
4802 type = TREE_TYPE (field);
4803 if (TREE_CODE (type) == REFERENCE_TYPE)
4804 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4805 "in class without a constructor", field);
4806 else if (CP_TYPE_CONST_P (type)
4807 && (!CLASS_TYPE_P (type)
4808 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4809 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4810 "in class without a constructor", field);
4814 /* Synthesize any needed methods. */
4815 add_implicitly_declared_members (t,
4816 cant_have_const_ctor,
4819 /* Check defaulted declarations here so we have cant_have_const_ctor
4820 and don't need to worry about clones. */
4821 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4822 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4824 int copy = copy_fn_p (fn);
4828 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
4829 : !no_const_asn_ref);
4830 bool fn_const_p = (copy == 2);
4832 if (fn_const_p && !imp_const_p)
4833 /* If the function is defaulted outside the class, we just
4834 give the synthesis error. */
4835 error ("%q+D declared to take const reference, but implicit "
4836 "declaration would take non-const", fn);
4837 else if (imp_const_p && !fn_const_p)
4838 error ("%q+D declared to take non-const reference cannot be "
4839 "defaulted in the class body", fn);
4841 defaulted_late_check (fn);
4844 if (LAMBDA_TYPE_P (t))
4846 /* "The closure type associated with a lambda-expression has a deleted
4847 default constructor and a deleted copy assignment operator." */
4848 TYPE_NEEDS_CONSTRUCTING (t) = 1;
4849 TYPE_HAS_COMPLEX_DFLT (t) = 1;
4850 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
4851 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 0;
4853 /* "This class type is not an aggregate." */
4854 CLASSTYPE_NON_AGGREGATE (t) = 1;
4857 /* Compute the 'literal type' property before we
4858 do anything with non-static member functions. */
4859 finalize_literal_type_property (t);
4861 /* Create the in-charge and not-in-charge variants of constructors
4863 clone_constructors_and_destructors (t);
4865 /* Process the using-declarations. */
4866 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4867 handle_using_decl (TREE_VALUE (access_decls), t);
4869 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4870 finish_struct_methods (t);
4872 /* Figure out whether or not we will need a cookie when dynamically
4873 allocating an array of this type. */
4874 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4875 = type_requires_array_cookie (t);
4878 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4879 accordingly. If a new vfield was created (because T doesn't have a
4880 primary base class), then the newly created field is returned. It
4881 is not added to the TYPE_FIELDS list; it is the caller's
4882 responsibility to do that. Accumulate declared virtual functions
4886 create_vtable_ptr (tree t, tree* virtuals_p)
4890 /* Collect the virtual functions declared in T. */
4891 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4892 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4893 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4895 tree new_virtual = make_node (TREE_LIST);
4897 BV_FN (new_virtual) = fn;
4898 BV_DELTA (new_virtual) = integer_zero_node;
4899 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4901 TREE_CHAIN (new_virtual) = *virtuals_p;
4902 *virtuals_p = new_virtual;
4905 /* If we couldn't find an appropriate base class, create a new field
4906 here. Even if there weren't any new virtual functions, we might need a
4907 new virtual function table if we're supposed to include vptrs in
4908 all classes that need them. */
4909 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4911 /* We build this decl with vtbl_ptr_type_node, which is a
4912 `vtable_entry_type*'. It might seem more precise to use
4913 `vtable_entry_type (*)[N]' where N is the number of virtual
4914 functions. However, that would require the vtable pointer in
4915 base classes to have a different type than the vtable pointer
4916 in derived classes. We could make that happen, but that
4917 still wouldn't solve all the problems. In particular, the
4918 type-based alias analysis code would decide that assignments
4919 to the base class vtable pointer can't alias assignments to
4920 the derived class vtable pointer, since they have different
4921 types. Thus, in a derived class destructor, where the base
4922 class constructor was inlined, we could generate bad code for
4923 setting up the vtable pointer.
4925 Therefore, we use one type for all vtable pointers. We still
4926 use a type-correct type; it's just doesn't indicate the array
4927 bounds. That's better than using `void*' or some such; it's
4928 cleaner, and it let's the alias analysis code know that these
4929 stores cannot alias stores to void*! */
4932 field = build_decl (input_location,
4933 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4934 DECL_VIRTUAL_P (field) = 1;
4935 DECL_ARTIFICIAL (field) = 1;
4936 DECL_FIELD_CONTEXT (field) = t;
4937 DECL_FCONTEXT (field) = t;
4938 if (TYPE_PACKED (t))
4939 DECL_PACKED (field) = 1;
4941 TYPE_VFIELD (t) = field;
4943 /* This class is non-empty. */
4944 CLASSTYPE_EMPTY_P (t) = 0;
4952 /* Add OFFSET to all base types of BINFO which is a base in the
4953 hierarchy dominated by T.
4955 OFFSET, which is a type offset, is number of bytes. */
4958 propagate_binfo_offsets (tree binfo, tree offset)
4964 /* Update BINFO's offset. */
4965 BINFO_OFFSET (binfo)
4966 = convert (sizetype,
4967 size_binop (PLUS_EXPR,
4968 convert (ssizetype, BINFO_OFFSET (binfo)),
4971 /* Find the primary base class. */
4972 primary_binfo = get_primary_binfo (binfo);
4974 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4975 propagate_binfo_offsets (primary_binfo, offset);
4977 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4979 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4981 /* Don't do the primary base twice. */
4982 if (base_binfo == primary_binfo)
4985 if (BINFO_VIRTUAL_P (base_binfo))
4988 propagate_binfo_offsets (base_binfo, offset);
4992 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4993 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4994 empty subobjects of T. */
4997 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
5001 bool first_vbase = true;
5004 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
5007 if (!abi_version_at_least(2))
5009 /* In G++ 3.2, we incorrectly rounded the size before laying out
5010 the virtual bases. */
5011 finish_record_layout (rli, /*free_p=*/false);
5012 #ifdef STRUCTURE_SIZE_BOUNDARY
5013 /* Packed structures don't need to have minimum size. */
5014 if (! TYPE_PACKED (t))
5015 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
5017 rli->offset = TYPE_SIZE_UNIT (t);
5018 rli->bitpos = bitsize_zero_node;
5019 rli->record_align = TYPE_ALIGN (t);
5022 /* Find the last field. The artificial fields created for virtual
5023 bases will go after the last extant field to date. */
5024 next_field = &TYPE_FIELDS (t);
5026 next_field = &DECL_CHAIN (*next_field);
5028 /* Go through the virtual bases, allocating space for each virtual
5029 base that is not already a primary base class. These are
5030 allocated in inheritance graph order. */
5031 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
5033 if (!BINFO_VIRTUAL_P (vbase))
5036 if (!BINFO_PRIMARY_P (vbase))
5038 tree basetype = TREE_TYPE (vbase);
5040 /* This virtual base is not a primary base of any class in the
5041 hierarchy, so we have to add space for it. */
5042 next_field = build_base_field (rli, vbase,
5043 offsets, next_field);
5045 /* If the first virtual base might have been placed at a
5046 lower address, had we started from CLASSTYPE_SIZE, rather
5047 than TYPE_SIZE, issue a warning. There can be both false
5048 positives and false negatives from this warning in rare
5049 cases; to deal with all the possibilities would probably
5050 require performing both layout algorithms and comparing
5051 the results which is not particularly tractable. */
5055 (size_binop (CEIL_DIV_EXPR,
5056 round_up_loc (input_location,
5058 CLASSTYPE_ALIGN (basetype)),
5060 BINFO_OFFSET (vbase))))
5062 "offset of virtual base %qT is not ABI-compliant and "
5063 "may change in a future version of GCC",
5066 first_vbase = false;
5071 /* Returns the offset of the byte just past the end of the base class
5075 end_of_base (tree binfo)
5079 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
5080 size = TYPE_SIZE_UNIT (char_type_node);
5081 else if (is_empty_class (BINFO_TYPE (binfo)))
5082 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
5083 allocate some space for it. It cannot have virtual bases, so
5084 TYPE_SIZE_UNIT is fine. */
5085 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5087 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5089 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
5092 /* Returns the offset of the byte just past the end of the base class
5093 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
5094 only non-virtual bases are included. */
5097 end_of_class (tree t, int include_virtuals_p)
5099 tree result = size_zero_node;
5100 VEC(tree,gc) *vbases;
5106 for (binfo = TYPE_BINFO (t), i = 0;
5107 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5109 if (!include_virtuals_p
5110 && BINFO_VIRTUAL_P (base_binfo)
5111 && (!BINFO_PRIMARY_P (base_binfo)
5112 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
5115 offset = end_of_base (base_binfo);
5116 if (INT_CST_LT_UNSIGNED (result, offset))
5120 /* G++ 3.2 did not check indirect virtual bases. */
5121 if (abi_version_at_least (2) && include_virtuals_p)
5122 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5123 VEC_iterate (tree, vbases, i, base_binfo); i++)
5125 offset = end_of_base (base_binfo);
5126 if (INT_CST_LT_UNSIGNED (result, offset))
5133 /* Warn about bases of T that are inaccessible because they are
5134 ambiguous. For example:
5137 struct T : public S {};
5138 struct U : public S, public T {};
5140 Here, `(S*) new U' is not allowed because there are two `S'
5144 warn_about_ambiguous_bases (tree t)
5147 VEC(tree,gc) *vbases;
5152 /* If there are no repeated bases, nothing can be ambiguous. */
5153 if (!CLASSTYPE_REPEATED_BASE_P (t))
5156 /* Check direct bases. */
5157 for (binfo = TYPE_BINFO (t), i = 0;
5158 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5160 basetype = BINFO_TYPE (base_binfo);
5162 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5163 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
5167 /* Check for ambiguous virtual bases. */
5169 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5170 VEC_iterate (tree, vbases, i, binfo); i++)
5172 basetype = BINFO_TYPE (binfo);
5174 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5175 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
5180 /* Compare two INTEGER_CSTs K1 and K2. */
5183 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
5185 return tree_int_cst_compare ((tree) k1, (tree) k2);
5188 /* Increase the size indicated in RLI to account for empty classes
5189 that are "off the end" of the class. */
5192 include_empty_classes (record_layout_info rli)
5197 /* It might be the case that we grew the class to allocate a
5198 zero-sized base class. That won't be reflected in RLI, yet,
5199 because we are willing to overlay multiple bases at the same
5200 offset. However, now we need to make sure that RLI is big enough
5201 to reflect the entire class. */
5202 eoc = end_of_class (rli->t,
5203 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
5204 rli_size = rli_size_unit_so_far (rli);
5205 if (TREE_CODE (rli_size) == INTEGER_CST
5206 && INT_CST_LT_UNSIGNED (rli_size, eoc))
5208 if (!abi_version_at_least (2))
5209 /* In version 1 of the ABI, the size of a class that ends with
5210 a bitfield was not rounded up to a whole multiple of a
5211 byte. Because rli_size_unit_so_far returns only the number
5212 of fully allocated bytes, any extra bits were not included
5214 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
5216 /* The size should have been rounded to a whole byte. */
5217 gcc_assert (tree_int_cst_equal
5218 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
5220 = size_binop (PLUS_EXPR,
5222 size_binop (MULT_EXPR,
5223 convert (bitsizetype,
5224 size_binop (MINUS_EXPR,
5226 bitsize_int (BITS_PER_UNIT)));
5227 normalize_rli (rli);
5231 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
5232 BINFO_OFFSETs for all of the base-classes. Position the vtable
5233 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
5236 layout_class_type (tree t, tree *virtuals_p)
5238 tree non_static_data_members;
5241 record_layout_info rli;
5242 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
5243 types that appear at that offset. */
5244 splay_tree empty_base_offsets;
5245 /* True if the last field layed out was a bit-field. */
5246 bool last_field_was_bitfield = false;
5247 /* The location at which the next field should be inserted. */
5249 /* T, as a base class. */
5252 /* Keep track of the first non-static data member. */
5253 non_static_data_members = TYPE_FIELDS (t);
5255 /* Start laying out the record. */
5256 rli = start_record_layout (t);
5258 /* Mark all the primary bases in the hierarchy. */
5259 determine_primary_bases (t);
5261 /* Create a pointer to our virtual function table. */
5262 vptr = create_vtable_ptr (t, virtuals_p);
5264 /* The vptr is always the first thing in the class. */
5267 DECL_CHAIN (vptr) = TYPE_FIELDS (t);
5268 TYPE_FIELDS (t) = vptr;
5269 next_field = &DECL_CHAIN (vptr);
5270 place_field (rli, vptr);
5273 next_field = &TYPE_FIELDS (t);
5275 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5276 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
5278 build_base_fields (rli, empty_base_offsets, next_field);
5280 /* Layout the non-static data members. */
5281 for (field = non_static_data_members; field; field = DECL_CHAIN (field))
5286 /* We still pass things that aren't non-static data members to
5287 the back end, in case it wants to do something with them. */
5288 if (TREE_CODE (field) != FIELD_DECL)
5290 place_field (rli, field);
5291 /* If the static data member has incomplete type, keep track
5292 of it so that it can be completed later. (The handling
5293 of pending statics in finish_record_layout is
5294 insufficient; consider:
5297 struct S2 { static S1 s1; };
5299 At this point, finish_record_layout will be called, but
5300 S1 is still incomplete.) */
5301 if (TREE_CODE (field) == VAR_DECL)
5303 maybe_register_incomplete_var (field);
5304 /* The visibility of static data members is determined
5305 at their point of declaration, not their point of
5307 determine_visibility (field);
5312 type = TREE_TYPE (field);
5313 if (type == error_mark_node)
5316 padding = NULL_TREE;
5318 /* If this field is a bit-field whose width is greater than its
5319 type, then there are some special rules for allocating
5321 if (DECL_C_BIT_FIELD (field)
5322 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
5326 bool was_unnamed_p = false;
5327 /* We must allocate the bits as if suitably aligned for the
5328 longest integer type that fits in this many bits. type
5329 of the field. Then, we are supposed to use the left over
5330 bits as additional padding. */
5331 for (itk = itk_char; itk != itk_none; ++itk)
5332 if (integer_types[itk] != NULL_TREE
5333 && (INT_CST_LT (size_int (MAX_FIXED_MODE_SIZE),
5334 TYPE_SIZE (integer_types[itk]))
5335 || INT_CST_LT (DECL_SIZE (field),
5336 TYPE_SIZE (integer_types[itk]))))
5339 /* ITK now indicates a type that is too large for the
5340 field. We have to back up by one to find the largest
5345 integer_type = integer_types[itk];
5346 } while (itk > 0 && integer_type == NULL_TREE);
5348 /* Figure out how much additional padding is required. GCC
5349 3.2 always created a padding field, even if it had zero
5351 if (!abi_version_at_least (2)
5352 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
5354 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
5355 /* In a union, the padding field must have the full width
5356 of the bit-field; all fields start at offset zero. */
5357 padding = DECL_SIZE (field);
5360 if (TREE_CODE (t) == UNION_TYPE)
5361 warning (OPT_Wabi, "size assigned to %qT may not be "
5362 "ABI-compliant and may change in a future "
5365 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
5366 TYPE_SIZE (integer_type));
5369 #ifdef PCC_BITFIELD_TYPE_MATTERS
5370 /* An unnamed bitfield does not normally affect the
5371 alignment of the containing class on a target where
5372 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5373 make any exceptions for unnamed bitfields when the
5374 bitfields are longer than their types. Therefore, we
5375 temporarily give the field a name. */
5376 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
5378 was_unnamed_p = true;
5379 DECL_NAME (field) = make_anon_name ();
5382 DECL_SIZE (field) = TYPE_SIZE (integer_type);
5383 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
5384 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
5385 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5386 empty_base_offsets);
5388 DECL_NAME (field) = NULL_TREE;
5389 /* Now that layout has been performed, set the size of the
5390 field to the size of its declared type; the rest of the
5391 field is effectively invisible. */
5392 DECL_SIZE (field) = TYPE_SIZE (type);
5393 /* We must also reset the DECL_MODE of the field. */
5394 if (abi_version_at_least (2))
5395 DECL_MODE (field) = TYPE_MODE (type);
5397 && DECL_MODE (field) != TYPE_MODE (type))
5398 /* Versions of G++ before G++ 3.4 did not reset the
5401 "the offset of %qD may not be ABI-compliant and may "
5402 "change in a future version of GCC", field);
5405 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5406 empty_base_offsets);
5408 /* Remember the location of any empty classes in FIELD. */
5409 if (abi_version_at_least (2))
5410 record_subobject_offsets (TREE_TYPE (field),
5411 byte_position(field),
5413 /*is_data_member=*/true);
5415 /* If a bit-field does not immediately follow another bit-field,
5416 and yet it starts in the middle of a byte, we have failed to
5417 comply with the ABI. */
5419 && DECL_C_BIT_FIELD (field)
5420 /* The TREE_NO_WARNING flag gets set by Objective-C when
5421 laying out an Objective-C class. The ObjC ABI differs
5422 from the C++ ABI, and so we do not want a warning
5424 && !TREE_NO_WARNING (field)
5425 && !last_field_was_bitfield
5426 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5427 DECL_FIELD_BIT_OFFSET (field),
5428 bitsize_unit_node)))
5429 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5430 "change in a future version of GCC", field);
5432 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5433 offset of the field. */
5435 && !abi_version_at_least (2)
5436 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5437 byte_position (field))
5438 && contains_empty_class_p (TREE_TYPE (field)))
5439 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5440 "classes to be placed at different locations in a "
5441 "future version of GCC", field);
5443 /* The middle end uses the type of expressions to determine the
5444 possible range of expression values. In order to optimize
5445 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5446 must be made aware of the width of "i", via its type.
5448 Because C++ does not have integer types of arbitrary width,
5449 we must (for the purposes of the front end) convert from the
5450 type assigned here to the declared type of the bitfield
5451 whenever a bitfield expression is used as an rvalue.
5452 Similarly, when assigning a value to a bitfield, the value
5453 must be converted to the type given the bitfield here. */
5454 if (DECL_C_BIT_FIELD (field))
5456 unsigned HOST_WIDE_INT width;
5457 tree ftype = TREE_TYPE (field);
5458 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5459 if (width != TYPE_PRECISION (ftype))
5462 = c_build_bitfield_integer_type (width,
5463 TYPE_UNSIGNED (ftype));
5465 = cp_build_qualified_type (TREE_TYPE (field),
5466 cp_type_quals (ftype));
5470 /* If we needed additional padding after this field, add it
5476 padding_field = build_decl (input_location,
5480 DECL_BIT_FIELD (padding_field) = 1;
5481 DECL_SIZE (padding_field) = padding;
5482 DECL_CONTEXT (padding_field) = t;
5483 DECL_ARTIFICIAL (padding_field) = 1;
5484 DECL_IGNORED_P (padding_field) = 1;
5485 layout_nonempty_base_or_field (rli, padding_field,
5487 empty_base_offsets);
5490 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5493 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5495 /* Make sure that we are on a byte boundary so that the size of
5496 the class without virtual bases will always be a round number
5498 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5499 normalize_rli (rli);
5502 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5504 if (!abi_version_at_least (2))
5505 include_empty_classes(rli);
5507 /* Delete all zero-width bit-fields from the list of fields. Now
5508 that the type is laid out they are no longer important. */
5509 remove_zero_width_bit_fields (t);
5511 /* Create the version of T used for virtual bases. We do not use
5512 make_class_type for this version; this is an artificial type. For
5513 a POD type, we just reuse T. */
5514 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5516 base_t = make_node (TREE_CODE (t));
5518 /* Set the size and alignment for the new type. In G++ 3.2, all
5519 empty classes were considered to have size zero when used as
5521 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5523 TYPE_SIZE (base_t) = bitsize_zero_node;
5524 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5525 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5527 "layout of classes derived from empty class %qT "
5528 "may change in a future version of GCC",
5535 /* If the ABI version is not at least two, and the last
5536 field was a bit-field, RLI may not be on a byte
5537 boundary. In particular, rli_size_unit_so_far might
5538 indicate the last complete byte, while rli_size_so_far
5539 indicates the total number of bits used. Therefore,
5540 rli_size_so_far, rather than rli_size_unit_so_far, is
5541 used to compute TYPE_SIZE_UNIT. */
5542 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5543 TYPE_SIZE_UNIT (base_t)
5544 = size_binop (MAX_EXPR,
5546 size_binop (CEIL_DIV_EXPR,
5547 rli_size_so_far (rli),
5548 bitsize_int (BITS_PER_UNIT))),
5551 = size_binop (MAX_EXPR,
5552 rli_size_so_far (rli),
5553 size_binop (MULT_EXPR,
5554 convert (bitsizetype, eoc),
5555 bitsize_int (BITS_PER_UNIT)));
5557 TYPE_ALIGN (base_t) = rli->record_align;
5558 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5560 /* Copy the fields from T. */
5561 next_field = &TYPE_FIELDS (base_t);
5562 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5563 if (TREE_CODE (field) == FIELD_DECL)
5565 *next_field = build_decl (input_location,
5569 DECL_CONTEXT (*next_field) = base_t;
5570 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5571 DECL_FIELD_BIT_OFFSET (*next_field)
5572 = DECL_FIELD_BIT_OFFSET (field);
5573 DECL_SIZE (*next_field) = DECL_SIZE (field);
5574 DECL_MODE (*next_field) = DECL_MODE (field);
5575 next_field = &DECL_CHAIN (*next_field);
5578 /* Record the base version of the type. */
5579 CLASSTYPE_AS_BASE (t) = base_t;
5580 TYPE_CONTEXT (base_t) = t;
5583 CLASSTYPE_AS_BASE (t) = t;
5585 /* Every empty class contains an empty class. */
5586 if (CLASSTYPE_EMPTY_P (t))
5587 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5589 /* Set the TYPE_DECL for this type to contain the right
5590 value for DECL_OFFSET, so that we can use it as part
5591 of a COMPONENT_REF for multiple inheritance. */
5592 layout_decl (TYPE_MAIN_DECL (t), 0);
5594 /* Now fix up any virtual base class types that we left lying
5595 around. We must get these done before we try to lay out the
5596 virtual function table. As a side-effect, this will remove the
5597 base subobject fields. */
5598 layout_virtual_bases (rli, empty_base_offsets);
5600 /* Make sure that empty classes are reflected in RLI at this
5602 include_empty_classes(rli);
5604 /* Make sure not to create any structures with zero size. */
5605 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5607 build_decl (input_location,
5608 FIELD_DECL, NULL_TREE, char_type_node));
5610 /* If this is a non-POD, declaring it packed makes a difference to how it
5611 can be used as a field; don't let finalize_record_size undo it. */
5612 if (TYPE_PACKED (t) && !layout_pod_type_p (t))
5613 rli->packed_maybe_necessary = true;
5615 /* Let the back end lay out the type. */
5616 finish_record_layout (rli, /*free_p=*/true);
5618 /* Warn about bases that can't be talked about due to ambiguity. */
5619 warn_about_ambiguous_bases (t);
5621 /* Now that we're done with layout, give the base fields the real types. */
5622 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5623 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5624 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5627 splay_tree_delete (empty_base_offsets);
5629 if (CLASSTYPE_EMPTY_P (t)
5630 && tree_int_cst_lt (sizeof_biggest_empty_class,
5631 TYPE_SIZE_UNIT (t)))
5632 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5635 /* Determine the "key method" for the class type indicated by TYPE,
5636 and set CLASSTYPE_KEY_METHOD accordingly. */
5639 determine_key_method (tree type)
5643 if (TYPE_FOR_JAVA (type)
5644 || processing_template_decl
5645 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5646 || CLASSTYPE_INTERFACE_KNOWN (type))
5649 /* The key method is the first non-pure virtual function that is not
5650 inline at the point of class definition. On some targets the
5651 key function may not be inline; those targets should not call
5652 this function until the end of the translation unit. */
5653 for (method = TYPE_METHODS (type); method != NULL_TREE;
5654 method = DECL_CHAIN (method))
5655 if (DECL_VINDEX (method) != NULL_TREE
5656 && ! DECL_DECLARED_INLINE_P (method)
5657 && ! DECL_PURE_VIRTUAL_P (method))
5659 CLASSTYPE_KEY_METHOD (type) = method;
5666 /* Perform processing required when the definition of T (a class type)
5670 finish_struct_1 (tree t)
5673 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5674 tree virtuals = NULL_TREE;
5677 if (COMPLETE_TYPE_P (t))
5679 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5680 error ("redefinition of %q#T", t);
5685 /* If this type was previously laid out as a forward reference,
5686 make sure we lay it out again. */
5687 TYPE_SIZE (t) = NULL_TREE;
5688 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5690 /* Make assumptions about the class; we'll reset the flags if
5692 CLASSTYPE_EMPTY_P (t) = 1;
5693 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5694 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5695 CLASSTYPE_LITERAL_P (t) = true;
5697 /* Do end-of-class semantic processing: checking the validity of the
5698 bases and members and add implicitly generated methods. */
5699 check_bases_and_members (t);
5701 /* Find the key method. */
5702 if (TYPE_CONTAINS_VPTR_P (t))
5704 /* The Itanium C++ ABI permits the key method to be chosen when
5705 the class is defined -- even though the key method so
5706 selected may later turn out to be an inline function. On
5707 some systems (such as ARM Symbian OS) the key method cannot
5708 be determined until the end of the translation unit. On such
5709 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5710 will cause the class to be added to KEYED_CLASSES. Then, in
5711 finish_file we will determine the key method. */
5712 if (targetm.cxx.key_method_may_be_inline ())
5713 determine_key_method (t);
5715 /* If a polymorphic class has no key method, we may emit the vtable
5716 in every translation unit where the class definition appears. */
5717 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5718 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5721 /* Layout the class itself. */
5722 layout_class_type (t, &virtuals);
5723 if (CLASSTYPE_AS_BASE (t) != t)
5724 /* We use the base type for trivial assignments, and hence it
5726 compute_record_mode (CLASSTYPE_AS_BASE (t));
5728 virtuals = modify_all_vtables (t, nreverse (virtuals));
5730 /* If necessary, create the primary vtable for this class. */
5731 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5733 /* We must enter these virtuals into the table. */
5734 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5735 build_primary_vtable (NULL_TREE, t);
5736 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5737 /* Here we know enough to change the type of our virtual
5738 function table, but we will wait until later this function. */
5739 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5742 if (TYPE_CONTAINS_VPTR_P (t))
5747 if (BINFO_VTABLE (TYPE_BINFO (t)))
5748 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5749 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5750 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5752 /* Add entries for virtual functions introduced by this class. */
5753 BINFO_VIRTUALS (TYPE_BINFO (t))
5754 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5756 /* Set DECL_VINDEX for all functions declared in this class. */
5757 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5759 fn = TREE_CHAIN (fn),
5760 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5761 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5763 tree fndecl = BV_FN (fn);
5765 if (DECL_THUNK_P (fndecl))
5766 /* A thunk. We should never be calling this entry directly
5767 from this vtable -- we'd use the entry for the non
5768 thunk base function. */
5769 DECL_VINDEX (fndecl) = NULL_TREE;
5770 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5771 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5775 finish_struct_bits (t);
5777 /* Complete the rtl for any static member objects of the type we're
5779 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
5780 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5781 && TREE_TYPE (x) != error_mark_node
5782 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5783 DECL_MODE (x) = TYPE_MODE (t);
5785 /* Done with FIELDS...now decide whether to sort these for
5786 faster lookups later.
5788 We use a small number because most searches fail (succeeding
5789 ultimately as the search bores through the inheritance
5790 hierarchy), and we want this failure to occur quickly. */
5792 n_fields = count_fields (TYPE_FIELDS (t));
5795 struct sorted_fields_type *field_vec = ggc_alloc_sorted_fields_type
5796 (sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5797 field_vec->len = n_fields;
5798 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5799 qsort (field_vec->elts, n_fields, sizeof (tree),
5801 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
5804 /* Complain if one of the field types requires lower visibility. */
5805 constrain_class_visibility (t);
5807 /* Make the rtl for any new vtables we have created, and unmark
5808 the base types we marked. */
5811 /* Build the VTT for T. */
5814 /* This warning does not make sense for Java classes, since they
5815 cannot have destructors. */
5816 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5820 dtor = CLASSTYPE_DESTRUCTORS (t);
5821 if (/* An implicitly declared destructor is always public. And,
5822 if it were virtual, we would have created it by now. */
5824 || (!DECL_VINDEX (dtor)
5825 && (/* public non-virtual */
5826 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5827 || (/* non-public non-virtual with friends */
5828 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5829 && (CLASSTYPE_FRIEND_CLASSES (t)
5830 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5831 warning (OPT_Wnon_virtual_dtor,
5832 "%q#T has virtual functions and accessible"
5833 " non-virtual destructor", t);
5838 if (warn_overloaded_virtual)
5841 /* Class layout, assignment of virtual table slots, etc., is now
5842 complete. Give the back end a chance to tweak the visibility of
5843 the class or perform any other required target modifications. */
5844 targetm.cxx.adjust_class_at_definition (t);
5846 maybe_suppress_debug_info (t);
5848 dump_class_hierarchy (t);
5850 /* Finish debugging output for this type. */
5851 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5853 if (TYPE_TRANSPARENT_AGGR (t))
5855 tree field = first_field (t);
5856 if (field == NULL_TREE || error_operand_p (field))
5858 error ("type transparent class %qT does not have any fields", t);
5859 TYPE_TRANSPARENT_AGGR (t) = 0;
5861 else if (DECL_ARTIFICIAL (field))
5863 if (DECL_FIELD_IS_BASE (field))
5864 error ("type transparent class %qT has base classes", t);
5867 gcc_checking_assert (DECL_VIRTUAL_P (field));
5868 error ("type transparent class %qT has virtual functions", t);
5870 TYPE_TRANSPARENT_AGGR (t) = 0;
5875 /* When T was built up, the member declarations were added in reverse
5876 order. Rearrange them to declaration order. */
5879 unreverse_member_declarations (tree t)
5885 /* The following lists are all in reverse order. Put them in
5886 declaration order now. */
5887 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5888 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5890 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5891 reverse order, so we can't just use nreverse. */
5893 for (x = TYPE_FIELDS (t);
5894 x && TREE_CODE (x) != TYPE_DECL;
5897 next = DECL_CHAIN (x);
5898 DECL_CHAIN (x) = prev;
5903 DECL_CHAIN (TYPE_FIELDS (t)) = x;
5905 TYPE_FIELDS (t) = prev;
5910 finish_struct (tree t, tree attributes)
5912 location_t saved_loc = input_location;
5914 /* Now that we've got all the field declarations, reverse everything
5916 unreverse_member_declarations (t);
5918 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5920 /* Nadger the current location so that diagnostics point to the start of
5921 the struct, not the end. */
5922 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5924 if (processing_template_decl)
5928 finish_struct_methods (t);
5929 TYPE_SIZE (t) = bitsize_zero_node;
5930 TYPE_SIZE_UNIT (t) = size_zero_node;
5932 /* We need to emit an error message if this type was used as a parameter
5933 and it is an abstract type, even if it is a template. We construct
5934 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5935 account and we call complete_vars with this type, which will check
5936 the PARM_DECLS. Note that while the type is being defined,
5937 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5938 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5939 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5940 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
5941 if (DECL_PURE_VIRTUAL_P (x))
5942 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5945 /* Remember current #pragma pack value. */
5946 TYPE_PRECISION (t) = maximum_field_alignment;
5949 finish_struct_1 (t);
5951 input_location = saved_loc;
5953 TYPE_BEING_DEFINED (t) = 0;
5955 if (current_class_type)
5958 error ("trying to finish struct, but kicked out due to previous parse errors");
5960 if (processing_template_decl && at_function_scope_p ())
5961 add_stmt (build_min (TAG_DEFN, t));
5966 /* Return the dynamic type of INSTANCE, if known.
5967 Used to determine whether the virtual function table is needed
5970 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5971 of our knowledge of its type. *NONNULL should be initialized
5972 before this function is called. */
5975 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5977 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5979 switch (TREE_CODE (instance))
5982 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5985 return RECUR (TREE_OPERAND (instance, 0));
5988 /* This is a call to a constructor, hence it's never zero. */
5989 if (TREE_HAS_CONSTRUCTOR (instance))
5993 return TREE_TYPE (instance);
5998 /* This is a call to a constructor, hence it's never zero. */
5999 if (TREE_HAS_CONSTRUCTOR (instance))
6003 return TREE_TYPE (instance);
6005 return RECUR (TREE_OPERAND (instance, 0));
6007 case POINTER_PLUS_EXPR:
6010 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
6011 return RECUR (TREE_OPERAND (instance, 0));
6012 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
6013 /* Propagate nonnull. */
6014 return RECUR (TREE_OPERAND (instance, 0));
6019 return RECUR (TREE_OPERAND (instance, 0));
6022 instance = TREE_OPERAND (instance, 0);
6025 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
6026 with a real object -- given &p->f, p can still be null. */
6027 tree t = get_base_address (instance);
6028 /* ??? Probably should check DECL_WEAK here. */
6029 if (t && DECL_P (t))
6032 return RECUR (instance);
6035 /* If this component is really a base class reference, then the field
6036 itself isn't definitive. */
6037 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
6038 return RECUR (TREE_OPERAND (instance, 0));
6039 return RECUR (TREE_OPERAND (instance, 1));
6043 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
6044 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
6048 return TREE_TYPE (TREE_TYPE (instance));
6050 /* fall through... */
6054 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
6058 return TREE_TYPE (instance);
6060 else if (instance == current_class_ptr)
6065 /* if we're in a ctor or dtor, we know our type. */
6066 if (DECL_LANG_SPECIFIC (current_function_decl)
6067 && (DECL_CONSTRUCTOR_P (current_function_decl)
6068 || DECL_DESTRUCTOR_P (current_function_decl)))
6072 return TREE_TYPE (TREE_TYPE (instance));
6075 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
6077 /* We only need one hash table because it is always left empty. */
6080 ht = htab_create (37,
6085 /* Reference variables should be references to objects. */
6089 /* Enter the INSTANCE in a table to prevent recursion; a
6090 variable's initializer may refer to the variable
6092 if (TREE_CODE (instance) == VAR_DECL
6093 && DECL_INITIAL (instance)
6094 && !type_dependent_expression_p_push (DECL_INITIAL (instance))
6095 && !htab_find (ht, instance))
6100 slot = htab_find_slot (ht, instance, INSERT);
6102 type = RECUR (DECL_INITIAL (instance));
6103 htab_remove_elt (ht, instance);
6116 /* Return nonzero if the dynamic type of INSTANCE is known, and
6117 equivalent to the static type. We also handle the case where
6118 INSTANCE is really a pointer. Return negative if this is a
6119 ctor/dtor. There the dynamic type is known, but this might not be
6120 the most derived base of the original object, and hence virtual
6121 bases may not be layed out according to this type.
6123 Used to determine whether the virtual function table is needed
6126 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6127 of our knowledge of its type. *NONNULL should be initialized
6128 before this function is called. */
6131 resolves_to_fixed_type_p (tree instance, int* nonnull)
6133 tree t = TREE_TYPE (instance);
6137 if (processing_template_decl)
6139 /* In a template we only care about the type of the result. */
6145 fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
6146 if (fixed == NULL_TREE)
6148 if (POINTER_TYPE_P (t))
6150 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
6152 return cdtorp ? -1 : 1;
6157 init_class_processing (void)
6159 current_class_depth = 0;
6160 current_class_stack_size = 10;
6162 = XNEWVEC (struct class_stack_node, current_class_stack_size);
6163 local_classes = VEC_alloc (tree, gc, 8);
6164 sizeof_biggest_empty_class = size_zero_node;
6166 ridpointers[(int) RID_PUBLIC] = access_public_node;
6167 ridpointers[(int) RID_PRIVATE] = access_private_node;
6168 ridpointers[(int) RID_PROTECTED] = access_protected_node;
6171 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
6174 restore_class_cache (void)
6178 /* We are re-entering the same class we just left, so we don't
6179 have to search the whole inheritance matrix to find all the
6180 decls to bind again. Instead, we install the cached
6181 class_shadowed list and walk through it binding names. */
6182 push_binding_level (previous_class_level);
6183 class_binding_level = previous_class_level;
6184 /* Restore IDENTIFIER_TYPE_VALUE. */
6185 for (type = class_binding_level->type_shadowed;
6187 type = TREE_CHAIN (type))
6188 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
6191 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
6192 appropriate for TYPE.
6194 So that we may avoid calls to lookup_name, we cache the _TYPE
6195 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
6197 For multiple inheritance, we perform a two-pass depth-first search
6198 of the type lattice. */
6201 pushclass (tree type)
6203 class_stack_node_t csn;
6205 type = TYPE_MAIN_VARIANT (type);
6207 /* Make sure there is enough room for the new entry on the stack. */
6208 if (current_class_depth + 1 >= current_class_stack_size)
6210 current_class_stack_size *= 2;
6212 = XRESIZEVEC (struct class_stack_node, current_class_stack,
6213 current_class_stack_size);
6216 /* Insert a new entry on the class stack. */
6217 csn = current_class_stack + current_class_depth;
6218 csn->name = current_class_name;
6219 csn->type = current_class_type;
6220 csn->access = current_access_specifier;
6221 csn->names_used = 0;
6223 current_class_depth++;
6225 /* Now set up the new type. */
6226 current_class_name = TYPE_NAME (type);
6227 if (TREE_CODE (current_class_name) == TYPE_DECL)
6228 current_class_name = DECL_NAME (current_class_name);
6229 current_class_type = type;
6231 /* By default, things in classes are private, while things in
6232 structures or unions are public. */
6233 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
6234 ? access_private_node
6235 : access_public_node);
6237 if (previous_class_level
6238 && type != previous_class_level->this_entity
6239 && current_class_depth == 1)
6241 /* Forcibly remove any old class remnants. */
6242 invalidate_class_lookup_cache ();
6245 if (!previous_class_level
6246 || type != previous_class_level->this_entity
6247 || current_class_depth > 1)
6250 restore_class_cache ();
6253 /* When we exit a toplevel class scope, we save its binding level so
6254 that we can restore it quickly. Here, we've entered some other
6255 class, so we must invalidate our cache. */
6258 invalidate_class_lookup_cache (void)
6260 previous_class_level = NULL;
6263 /* Get out of the current class scope. If we were in a class scope
6264 previously, that is the one popped to. */
6271 current_class_depth--;
6272 current_class_name = current_class_stack[current_class_depth].name;
6273 current_class_type = current_class_stack[current_class_depth].type;
6274 current_access_specifier = current_class_stack[current_class_depth].access;
6275 if (current_class_stack[current_class_depth].names_used)
6276 splay_tree_delete (current_class_stack[current_class_depth].names_used);
6279 /* Mark the top of the class stack as hidden. */
6282 push_class_stack (void)
6284 if (current_class_depth)
6285 ++current_class_stack[current_class_depth - 1].hidden;
6288 /* Mark the top of the class stack as un-hidden. */
6291 pop_class_stack (void)
6293 if (current_class_depth)
6294 --current_class_stack[current_class_depth - 1].hidden;
6297 /* Returns 1 if the class type currently being defined is either T or
6298 a nested type of T. */
6301 currently_open_class (tree t)
6305 if (!CLASS_TYPE_P (t))
6308 t = TYPE_MAIN_VARIANT (t);
6310 /* We start looking from 1 because entry 0 is from global scope,
6312 for (i = current_class_depth; i > 0; --i)
6315 if (i == current_class_depth)
6316 c = current_class_type;
6319 if (current_class_stack[i].hidden)
6321 c = current_class_stack[i].type;
6325 if (same_type_p (c, t))
6331 /* If either current_class_type or one of its enclosing classes are derived
6332 from T, return the appropriate type. Used to determine how we found
6333 something via unqualified lookup. */
6336 currently_open_derived_class (tree t)
6340 /* The bases of a dependent type are unknown. */
6341 if (dependent_type_p (t))
6344 if (!current_class_type)
6347 if (DERIVED_FROM_P (t, current_class_type))
6348 return current_class_type;
6350 for (i = current_class_depth - 1; i > 0; --i)
6352 if (current_class_stack[i].hidden)
6354 if (DERIVED_FROM_P (t, current_class_stack[i].type))
6355 return current_class_stack[i].type;
6361 /* Returns the innermost class type which is not a lambda closure type. */
6364 current_nonlambda_class_type (void)
6368 /* We start looking from 1 because entry 0 is from global scope,
6370 for (i = current_class_depth; i > 0; --i)
6373 if (i == current_class_depth)
6374 c = current_class_type;
6377 if (current_class_stack[i].hidden)
6379 c = current_class_stack[i].type;
6383 if (!LAMBDA_TYPE_P (c))
6389 /* When entering a class scope, all enclosing class scopes' names with
6390 static meaning (static variables, static functions, types and
6391 enumerators) have to be visible. This recursive function calls
6392 pushclass for all enclosing class contexts until global or a local
6393 scope is reached. TYPE is the enclosed class. */
6396 push_nested_class (tree type)
6398 /* A namespace might be passed in error cases, like A::B:C. */
6399 if (type == NULL_TREE
6400 || !CLASS_TYPE_P (type))
6403 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
6408 /* Undoes a push_nested_class call. */
6411 pop_nested_class (void)
6413 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
6416 if (context && CLASS_TYPE_P (context))
6417 pop_nested_class ();
6420 /* Returns the number of extern "LANG" blocks we are nested within. */
6423 current_lang_depth (void)
6425 return VEC_length (tree, current_lang_base);
6428 /* Set global variables CURRENT_LANG_NAME to appropriate value
6429 so that behavior of name-mangling machinery is correct. */
6432 push_lang_context (tree name)
6434 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
6436 if (name == lang_name_cplusplus)
6438 current_lang_name = name;
6440 else if (name == lang_name_java)
6442 current_lang_name = name;
6443 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6444 (See record_builtin_java_type in decl.c.) However, that causes
6445 incorrect debug entries if these types are actually used.
6446 So we re-enable debug output after extern "Java". */
6447 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
6448 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
6449 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
6450 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
6451 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
6452 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
6453 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
6454 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
6456 else if (name == lang_name_c)
6458 current_lang_name = name;
6461 error ("language string %<\"%E\"%> not recognized", name);
6464 /* Get out of the current language scope. */
6467 pop_lang_context (void)
6469 current_lang_name = VEC_pop (tree, current_lang_base);
6472 /* Type instantiation routines. */
6474 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6475 matches the TARGET_TYPE. If there is no satisfactory match, return
6476 error_mark_node, and issue an error & warning messages under
6477 control of FLAGS. Permit pointers to member function if FLAGS
6478 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6479 a template-id, and EXPLICIT_TARGS are the explicitly provided
6482 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6483 is the base path used to reference those member functions. If
6484 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6485 resolved to a member function, access checks will be performed and
6486 errors issued if appropriate. */
6489 resolve_address_of_overloaded_function (tree target_type,
6491 tsubst_flags_t flags,
6493 tree explicit_targs,
6496 /* Here's what the standard says:
6500 If the name is a function template, template argument deduction
6501 is done, and if the argument deduction succeeds, the deduced
6502 arguments are used to generate a single template function, which
6503 is added to the set of overloaded functions considered.
6505 Non-member functions and static member functions match targets of
6506 type "pointer-to-function" or "reference-to-function." Nonstatic
6507 member functions match targets of type "pointer-to-member
6508 function;" the function type of the pointer to member is used to
6509 select the member function from the set of overloaded member
6510 functions. If a nonstatic member function is selected, the
6511 reference to the overloaded function name is required to have the
6512 form of a pointer to member as described in 5.3.1.
6514 If more than one function is selected, any template functions in
6515 the set are eliminated if the set also contains a non-template
6516 function, and any given template function is eliminated if the
6517 set contains a second template function that is more specialized
6518 than the first according to the partial ordering rules 14.5.5.2.
6519 After such eliminations, if any, there shall remain exactly one
6520 selected function. */
6523 /* We store the matches in a TREE_LIST rooted here. The functions
6524 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6525 interoperability with most_specialized_instantiation. */
6526 tree matches = NULL_TREE;
6528 tree target_fn_type;
6530 /* By the time we get here, we should be seeing only real
6531 pointer-to-member types, not the internal POINTER_TYPE to
6532 METHOD_TYPE representation. */
6533 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6534 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6536 gcc_assert (is_overloaded_fn (overload));
6538 /* Check that the TARGET_TYPE is reasonable. */
6539 if (TYPE_PTRFN_P (target_type))
6541 else if (TYPE_PTRMEMFUNC_P (target_type))
6542 /* This is OK, too. */
6544 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6545 /* This is OK, too. This comes from a conversion to reference
6547 target_type = build_reference_type (target_type);
6550 if (flags & tf_error)
6551 error ("cannot resolve overloaded function %qD based on"
6552 " conversion to type %qT",
6553 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6554 return error_mark_node;
6557 /* Non-member functions and static member functions match targets of type
6558 "pointer-to-function" or "reference-to-function." Nonstatic member
6559 functions match targets of type "pointer-to-member-function;" the
6560 function type of the pointer to member is used to select the member
6561 function from the set of overloaded member functions.
6563 So figure out the FUNCTION_TYPE that we want to match against. */
6564 target_fn_type = static_fn_type (target_type);
6566 /* If we can find a non-template function that matches, we can just
6567 use it. There's no point in generating template instantiations
6568 if we're just going to throw them out anyhow. But, of course, we
6569 can only do this when we don't *need* a template function. */
6574 for (fns = overload; fns; fns = OVL_NEXT (fns))
6576 tree fn = OVL_CURRENT (fns);
6578 if (TREE_CODE (fn) == TEMPLATE_DECL)
6579 /* We're not looking for templates just yet. */
6582 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6584 /* We're looking for a non-static member, and this isn't
6585 one, or vice versa. */
6588 /* Ignore functions which haven't been explicitly
6590 if (DECL_ANTICIPATED (fn))
6593 /* See if there's a match. */
6594 if (same_type_p (target_fn_type, static_fn_type (fn)))
6595 matches = tree_cons (fn, NULL_TREE, matches);
6599 /* Now, if we've already got a match (or matches), there's no need
6600 to proceed to the template functions. But, if we don't have a
6601 match we need to look at them, too. */
6604 tree target_arg_types;
6605 tree target_ret_type;
6608 unsigned int nargs, ia;
6611 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6612 target_ret_type = TREE_TYPE (target_fn_type);
6614 nargs = list_length (target_arg_types);
6615 args = XALLOCAVEC (tree, nargs);
6616 for (arg = target_arg_types, ia = 0;
6617 arg != NULL_TREE && arg != void_list_node;
6618 arg = TREE_CHAIN (arg), ++ia)
6619 args[ia] = TREE_VALUE (arg);
6622 for (fns = overload; fns; fns = OVL_NEXT (fns))
6624 tree fn = OVL_CURRENT (fns);
6628 if (TREE_CODE (fn) != TEMPLATE_DECL)
6629 /* We're only looking for templates. */
6632 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6634 /* We're not looking for a non-static member, and this is
6635 one, or vice versa. */
6638 /* Try to do argument deduction. */
6639 targs = make_tree_vec (DECL_NTPARMS (fn));
6640 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6641 target_ret_type, DEDUCE_EXACT,
6642 LOOKUP_NORMAL, false))
6643 /* Argument deduction failed. */
6646 /* Instantiate the template. */
6647 instantiation = instantiate_template (fn, targs, flags);
6648 if (instantiation == error_mark_node)
6649 /* Instantiation failed. */
6652 /* See if there's a match. */
6653 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
6654 matches = tree_cons (instantiation, fn, matches);
6657 /* Now, remove all but the most specialized of the matches. */
6660 tree match = most_specialized_instantiation (matches);
6662 if (match != error_mark_node)
6663 matches = tree_cons (TREE_PURPOSE (match),
6669 /* Now we should have exactly one function in MATCHES. */
6670 if (matches == NULL_TREE)
6672 /* There were *no* matches. */
6673 if (flags & tf_error)
6675 error ("no matches converting function %qD to type %q#T",
6676 DECL_NAME (OVL_CURRENT (overload)),
6679 print_candidates (overload);
6681 return error_mark_node;
6683 else if (TREE_CHAIN (matches))
6685 /* There were too many matches. First check if they're all
6686 the same function. */
6689 fn = TREE_PURPOSE (matches);
6690 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6691 if (!decls_match (fn, TREE_PURPOSE (match)))
6696 if (flags & tf_error)
6698 error ("converting overloaded function %qD to type %q#T is ambiguous",
6699 DECL_NAME (OVL_FUNCTION (overload)),
6702 /* Since print_candidates expects the functions in the
6703 TREE_VALUE slot, we flip them here. */
6704 for (match = matches; match; match = TREE_CHAIN (match))
6705 TREE_VALUE (match) = TREE_PURPOSE (match);
6707 print_candidates (matches);
6710 return error_mark_node;
6714 /* Good, exactly one match. Now, convert it to the correct type. */
6715 fn = TREE_PURPOSE (matches);
6717 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6718 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6720 static int explained;
6722 if (!(flags & tf_error))
6723 return error_mark_node;
6725 permerror (input_location, "assuming pointer to member %qD", fn);
6728 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6733 /* If we're doing overload resolution purely for the purpose of
6734 determining conversion sequences, we should not consider the
6735 function used. If this conversion sequence is selected, the
6736 function will be marked as used at this point. */
6737 if (!(flags & tf_conv))
6739 /* Make =delete work with SFINAE. */
6740 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6741 return error_mark_node;
6746 /* We could not check access to member functions when this
6747 expression was originally created since we did not know at that
6748 time to which function the expression referred. */
6749 if (!(flags & tf_no_access_control)
6750 && DECL_FUNCTION_MEMBER_P (fn))
6752 gcc_assert (access_path);
6753 perform_or_defer_access_check (access_path, fn, fn);
6756 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6757 return cp_build_addr_expr (fn, flags);
6760 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6761 will mark the function as addressed, but here we must do it
6763 cxx_mark_addressable (fn);
6769 /* This function will instantiate the type of the expression given in
6770 RHS to match the type of LHSTYPE. If errors exist, then return
6771 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6772 we complain on errors. If we are not complaining, never modify rhs,
6773 as overload resolution wants to try many possible instantiations, in
6774 the hope that at least one will work.
6776 For non-recursive calls, LHSTYPE should be a function, pointer to
6777 function, or a pointer to member function. */
6780 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6782 tsubst_flags_t flags_in = flags;
6783 tree access_path = NULL_TREE;
6785 flags &= ~tf_ptrmem_ok;
6787 if (lhstype == unknown_type_node)
6789 if (flags & tf_error)
6790 error ("not enough type information");
6791 return error_mark_node;
6794 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6796 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6798 if (flag_ms_extensions
6799 && TYPE_PTRMEMFUNC_P (lhstype)
6800 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6801 /* Microsoft allows `A::f' to be resolved to a
6802 pointer-to-member. */
6806 if (flags & tf_error)
6807 error ("argument of type %qT does not match %qT",
6808 TREE_TYPE (rhs), lhstype);
6809 return error_mark_node;
6813 if (TREE_CODE (rhs) == BASELINK)
6815 access_path = BASELINK_ACCESS_BINFO (rhs);
6816 rhs = BASELINK_FUNCTIONS (rhs);
6819 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6820 deduce any type information. */
6821 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6823 if (flags & tf_error)
6824 error ("not enough type information");
6825 return error_mark_node;
6828 /* There only a few kinds of expressions that may have a type
6829 dependent on overload resolution. */
6830 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6831 || TREE_CODE (rhs) == COMPONENT_REF
6832 || really_overloaded_fn (rhs)
6833 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
6835 /* This should really only be used when attempting to distinguish
6836 what sort of a pointer to function we have. For now, any
6837 arithmetic operation which is not supported on pointers
6838 is rejected as an error. */
6840 switch (TREE_CODE (rhs))
6844 tree member = TREE_OPERAND (rhs, 1);
6846 member = instantiate_type (lhstype, member, flags);
6847 if (member != error_mark_node
6848 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6849 /* Do not lose object's side effects. */
6850 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6851 TREE_OPERAND (rhs, 0), member);
6856 rhs = TREE_OPERAND (rhs, 1);
6857 if (BASELINK_P (rhs))
6858 return instantiate_type (lhstype, rhs, flags_in);
6860 /* This can happen if we are forming a pointer-to-member for a
6862 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6866 case TEMPLATE_ID_EXPR:
6868 tree fns = TREE_OPERAND (rhs, 0);
6869 tree args = TREE_OPERAND (rhs, 1);
6872 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6873 /*template_only=*/true,
6880 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6881 /*template_only=*/false,
6882 /*explicit_targs=*/NULL_TREE,
6887 if (PTRMEM_OK_P (rhs))
6888 flags |= tf_ptrmem_ok;
6890 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6894 return error_mark_node;
6899 return error_mark_node;
6902 /* Return the name of the virtual function pointer field
6903 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6904 this may have to look back through base types to find the
6905 ultimate field name. (For single inheritance, these could
6906 all be the same name. Who knows for multiple inheritance). */
6909 get_vfield_name (tree type)
6911 tree binfo, base_binfo;
6914 for (binfo = TYPE_BINFO (type);
6915 BINFO_N_BASE_BINFOS (binfo);
6918 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6920 if (BINFO_VIRTUAL_P (base_binfo)
6921 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6925 type = BINFO_TYPE (binfo);
6926 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6927 + TYPE_NAME_LENGTH (type) + 2);
6928 sprintf (buf, VFIELD_NAME_FORMAT,
6929 IDENTIFIER_POINTER (constructor_name (type)));
6930 return get_identifier (buf);
6934 print_class_statistics (void)
6936 #ifdef GATHER_STATISTICS
6937 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6938 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6941 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6942 n_vtables, n_vtable_searches);
6943 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6944 n_vtable_entries, n_vtable_elems);
6949 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6950 according to [class]:
6951 The class-name is also inserted
6952 into the scope of the class itself. For purposes of access checking,
6953 the inserted class name is treated as if it were a public member name. */
6956 build_self_reference (void)
6958 tree name = constructor_name (current_class_type);
6959 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6962 DECL_NONLOCAL (value) = 1;
6963 DECL_CONTEXT (value) = current_class_type;
6964 DECL_ARTIFICIAL (value) = 1;
6965 SET_DECL_SELF_REFERENCE_P (value);
6966 set_underlying_type (value);
6968 if (processing_template_decl)
6969 value = push_template_decl (value);
6971 saved_cas = current_access_specifier;
6972 current_access_specifier = access_public_node;
6973 finish_member_declaration (value);
6974 current_access_specifier = saved_cas;
6977 /* Returns 1 if TYPE contains only padding bytes. */
6980 is_empty_class (tree type)
6982 if (type == error_mark_node)
6985 if (! CLASS_TYPE_P (type))
6988 /* In G++ 3.2, whether or not a class was empty was determined by
6989 looking at its size. */
6990 if (abi_version_at_least (2))
6991 return CLASSTYPE_EMPTY_P (type);
6993 return integer_zerop (CLASSTYPE_SIZE (type));
6996 /* Returns true if TYPE contains an empty class. */
6999 contains_empty_class_p (tree type)
7001 if (is_empty_class (type))
7003 if (CLASS_TYPE_P (type))
7010 for (binfo = TYPE_BINFO (type), i = 0;
7011 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7012 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
7014 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
7015 if (TREE_CODE (field) == FIELD_DECL
7016 && !DECL_ARTIFICIAL (field)
7017 && is_empty_class (TREE_TYPE (field)))
7020 else if (TREE_CODE (type) == ARRAY_TYPE)
7021 return contains_empty_class_p (TREE_TYPE (type));
7025 /* Returns true if TYPE contains no actual data, just various
7026 possible combinations of empty classes and possibly a vptr. */
7029 is_really_empty_class (tree type)
7031 if (CLASS_TYPE_P (type))
7038 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
7039 out, but we'd like to be able to check this before then. */
7040 if (COMPLETE_TYPE_P (type) && is_empty_class (type))
7043 for (binfo = TYPE_BINFO (type), i = 0;
7044 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7045 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
7047 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
7048 if (TREE_CODE (field) == FIELD_DECL
7049 && !DECL_ARTIFICIAL (field)
7050 && !is_really_empty_class (TREE_TYPE (field)))
7054 else if (TREE_CODE (type) == ARRAY_TYPE)
7055 return is_really_empty_class (TREE_TYPE (type));
7059 /* Note that NAME was looked up while the current class was being
7060 defined and that the result of that lookup was DECL. */
7063 maybe_note_name_used_in_class (tree name, tree decl)
7065 splay_tree names_used;
7067 /* If we're not defining a class, there's nothing to do. */
7068 if (!(innermost_scope_kind() == sk_class
7069 && TYPE_BEING_DEFINED (current_class_type)
7070 && !LAMBDA_TYPE_P (current_class_type)))
7073 /* If there's already a binding for this NAME, then we don't have
7074 anything to worry about. */
7075 if (lookup_member (current_class_type, name,
7076 /*protect=*/0, /*want_type=*/false))
7079 if (!current_class_stack[current_class_depth - 1].names_used)
7080 current_class_stack[current_class_depth - 1].names_used
7081 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
7082 names_used = current_class_stack[current_class_depth - 1].names_used;
7084 splay_tree_insert (names_used,
7085 (splay_tree_key) name,
7086 (splay_tree_value) decl);
7089 /* Note that NAME was declared (as DECL) in the current class. Check
7090 to see that the declaration is valid. */
7093 note_name_declared_in_class (tree name, tree decl)
7095 splay_tree names_used;
7098 /* Look to see if we ever used this name. */
7100 = current_class_stack[current_class_depth - 1].names_used;
7103 /* The C language allows members to be declared with a type of the same
7104 name, and the C++ standard says this diagnostic is not required. So
7105 allow it in extern "C" blocks unless predantic is specified.
7106 Allow it in all cases if -ms-extensions is specified. */
7107 if ((!pedantic && current_lang_name == lang_name_c)
7108 || flag_ms_extensions)
7110 n = splay_tree_lookup (names_used, (splay_tree_key) name);
7113 /* [basic.scope.class]
7115 A name N used in a class S shall refer to the same declaration
7116 in its context and when re-evaluated in the completed scope of
7118 permerror (input_location, "declaration of %q#D", decl);
7119 permerror (input_location, "changes meaning of %qD from %q+#D",
7120 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
7124 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
7125 Secondary vtables are merged with primary vtables; this function
7126 will return the VAR_DECL for the primary vtable. */
7129 get_vtbl_decl_for_binfo (tree binfo)
7133 decl = BINFO_VTABLE (binfo);
7134 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
7136 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
7137 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
7140 gcc_assert (TREE_CODE (decl) == VAR_DECL);
7145 /* Returns the binfo for the primary base of BINFO. If the resulting
7146 BINFO is a virtual base, and it is inherited elsewhere in the
7147 hierarchy, then the returned binfo might not be the primary base of
7148 BINFO in the complete object. Check BINFO_PRIMARY_P or
7149 BINFO_LOST_PRIMARY_P to be sure. */
7152 get_primary_binfo (tree binfo)
7156 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
7160 return copied_binfo (primary_base, binfo);
7163 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
7166 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
7169 fprintf (stream, "%*s", indent, "");
7173 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
7174 INDENT should be zero when called from the top level; it is
7175 incremented recursively. IGO indicates the next expected BINFO in
7176 inheritance graph ordering. */
7179 dump_class_hierarchy_r (FILE *stream,
7189 indented = maybe_indent_hierarchy (stream, indent, 0);
7190 fprintf (stream, "%s (0x%lx) ",
7191 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
7192 (unsigned long) binfo);
7195 fprintf (stream, "alternative-path\n");
7198 igo = TREE_CHAIN (binfo);
7200 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
7201 tree_low_cst (BINFO_OFFSET (binfo), 0));
7202 if (is_empty_class (BINFO_TYPE (binfo)))
7203 fprintf (stream, " empty");
7204 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
7205 fprintf (stream, " nearly-empty");
7206 if (BINFO_VIRTUAL_P (binfo))
7207 fprintf (stream, " virtual");
7208 fprintf (stream, "\n");
7211 if (BINFO_PRIMARY_P (binfo))
7213 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7214 fprintf (stream, " primary-for %s (0x%lx)",
7215 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
7216 TFF_PLAIN_IDENTIFIER),
7217 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
7219 if (BINFO_LOST_PRIMARY_P (binfo))
7221 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7222 fprintf (stream, " lost-primary");
7225 fprintf (stream, "\n");
7227 if (!(flags & TDF_SLIM))
7231 if (BINFO_SUBVTT_INDEX (binfo))
7233 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7234 fprintf (stream, " subvttidx=%s",
7235 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
7236 TFF_PLAIN_IDENTIFIER));
7238 if (BINFO_VPTR_INDEX (binfo))
7240 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7241 fprintf (stream, " vptridx=%s",
7242 expr_as_string (BINFO_VPTR_INDEX (binfo),
7243 TFF_PLAIN_IDENTIFIER));
7245 if (BINFO_VPTR_FIELD (binfo))
7247 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7248 fprintf (stream, " vbaseoffset=%s",
7249 expr_as_string (BINFO_VPTR_FIELD (binfo),
7250 TFF_PLAIN_IDENTIFIER));
7252 if (BINFO_VTABLE (binfo))
7254 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7255 fprintf (stream, " vptr=%s",
7256 expr_as_string (BINFO_VTABLE (binfo),
7257 TFF_PLAIN_IDENTIFIER));
7261 fprintf (stream, "\n");
7264 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
7265 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
7270 /* Dump the BINFO hierarchy for T. */
7273 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
7275 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7276 fprintf (stream, " size=%lu align=%lu\n",
7277 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
7278 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
7279 fprintf (stream, " base size=%lu base align=%lu\n",
7280 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
7282 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
7284 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
7285 fprintf (stream, "\n");
7288 /* Debug interface to hierarchy dumping. */
7291 debug_class (tree t)
7293 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
7297 dump_class_hierarchy (tree t)
7300 FILE *stream = dump_begin (TDI_class, &flags);
7304 dump_class_hierarchy_1 (stream, flags, t);
7305 dump_end (TDI_class, stream);
7310 dump_array (FILE * stream, tree decl)
7313 unsigned HOST_WIDE_INT ix;
7315 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
7317 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
7319 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
7320 fprintf (stream, " %s entries",
7321 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
7322 TFF_PLAIN_IDENTIFIER));
7323 fprintf (stream, "\n");
7325 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
7327 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
7328 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
7332 dump_vtable (tree t, tree binfo, tree vtable)
7335 FILE *stream = dump_begin (TDI_class, &flags);
7340 if (!(flags & TDF_SLIM))
7342 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
7344 fprintf (stream, "%s for %s",
7345 ctor_vtbl_p ? "Construction vtable" : "Vtable",
7346 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
7349 if (!BINFO_VIRTUAL_P (binfo))
7350 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
7351 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7353 fprintf (stream, "\n");
7354 dump_array (stream, vtable);
7355 fprintf (stream, "\n");
7358 dump_end (TDI_class, stream);
7362 dump_vtt (tree t, tree vtt)
7365 FILE *stream = dump_begin (TDI_class, &flags);
7370 if (!(flags & TDF_SLIM))
7372 fprintf (stream, "VTT for %s\n",
7373 type_as_string (t, TFF_PLAIN_IDENTIFIER));
7374 dump_array (stream, vtt);
7375 fprintf (stream, "\n");
7378 dump_end (TDI_class, stream);
7381 /* Dump a function or thunk and its thunkees. */
7384 dump_thunk (FILE *stream, int indent, tree thunk)
7386 static const char spaces[] = " ";
7387 tree name = DECL_NAME (thunk);
7390 fprintf (stream, "%.*s%p %s %s", indent, spaces,
7392 !DECL_THUNK_P (thunk) ? "function"
7393 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
7394 name ? IDENTIFIER_POINTER (name) : "<unset>");
7395 if (DECL_THUNK_P (thunk))
7397 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
7398 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
7400 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
7401 if (!virtual_adjust)
7403 else if (DECL_THIS_THUNK_P (thunk))
7404 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
7405 tree_low_cst (virtual_adjust, 0));
7407 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
7408 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
7409 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
7410 if (THUNK_ALIAS (thunk))
7411 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
7413 fprintf (stream, "\n");
7414 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
7415 dump_thunk (stream, indent + 2, thunks);
7418 /* Dump the thunks for FN. */
7421 debug_thunks (tree fn)
7423 dump_thunk (stderr, 0, fn);
7426 /* Virtual function table initialization. */
7428 /* Create all the necessary vtables for T and its base classes. */
7431 finish_vtbls (tree t)
7434 VEC(constructor_elt,gc) *v = NULL;
7435 tree vtable = BINFO_VTABLE (TYPE_BINFO (t));
7437 /* We lay out the primary and secondary vtables in one contiguous
7438 vtable. The primary vtable is first, followed by the non-virtual
7439 secondary vtables in inheritance graph order. */
7440 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t),
7443 /* Then come the virtual bases, also in inheritance graph order. */
7444 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
7446 if (!BINFO_VIRTUAL_P (vbase))
7448 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), vtable, t, &v);
7451 if (BINFO_VTABLE (TYPE_BINFO (t)))
7452 initialize_vtable (TYPE_BINFO (t), v);
7455 /* Initialize the vtable for BINFO with the INITS. */
7458 initialize_vtable (tree binfo, VEC(constructor_elt,gc) *inits)
7462 layout_vtable_decl (binfo, VEC_length (constructor_elt, inits));
7463 decl = get_vtbl_decl_for_binfo (binfo);
7464 initialize_artificial_var (decl, inits);
7465 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
7468 /* Build the VTT (virtual table table) for T.
7469 A class requires a VTT if it has virtual bases.
7472 1 - primary virtual pointer for complete object T
7473 2 - secondary VTTs for each direct non-virtual base of T which requires a
7475 3 - secondary virtual pointers for each direct or indirect base of T which
7476 has virtual bases or is reachable via a virtual path from T.
7477 4 - secondary VTTs for each direct or indirect virtual base of T.
7479 Secondary VTTs look like complete object VTTs without part 4. */
7487 VEC(constructor_elt,gc) *inits;
7489 /* Build up the initializers for the VTT. */
7491 index = size_zero_node;
7492 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7494 /* If we didn't need a VTT, we're done. */
7498 /* Figure out the type of the VTT. */
7499 type = build_array_of_n_type (const_ptr_type_node,
7500 VEC_length (constructor_elt, inits));
7502 /* Now, build the VTT object itself. */
7503 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7504 initialize_artificial_var (vtt, inits);
7505 /* Add the VTT to the vtables list. */
7506 DECL_CHAIN (vtt) = DECL_CHAIN (CLASSTYPE_VTABLES (t));
7507 DECL_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7512 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7513 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7514 and CHAIN the vtable pointer for this binfo after construction is
7515 complete. VALUE can also be another BINFO, in which case we recurse. */
7518 binfo_ctor_vtable (tree binfo)
7524 vt = BINFO_VTABLE (binfo);
7525 if (TREE_CODE (vt) == TREE_LIST)
7526 vt = TREE_VALUE (vt);
7527 if (TREE_CODE (vt) == TREE_BINFO)
7536 /* Data for secondary VTT initialization. */
7537 typedef struct secondary_vptr_vtt_init_data_s
7539 /* Is this the primary VTT? */
7542 /* Current index into the VTT. */
7545 /* Vector of initializers built up. */
7546 VEC(constructor_elt,gc) *inits;
7548 /* The type being constructed by this secondary VTT. */
7549 tree type_being_constructed;
7550 } secondary_vptr_vtt_init_data;
7552 /* Recursively build the VTT-initializer for BINFO (which is in the
7553 hierarchy dominated by T). INITS points to the end of the initializer
7554 list to date. INDEX is the VTT index where the next element will be
7555 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7556 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7557 for virtual bases of T. When it is not so, we build the constructor
7558 vtables for the BINFO-in-T variant. */
7561 build_vtt_inits (tree binfo, tree t, VEC(constructor_elt,gc) **inits, tree *index)
7566 secondary_vptr_vtt_init_data data;
7567 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7569 /* We only need VTTs for subobjects with virtual bases. */
7570 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7573 /* We need to use a construction vtable if this is not the primary
7577 build_ctor_vtbl_group (binfo, t);
7579 /* Record the offset in the VTT where this sub-VTT can be found. */
7580 BINFO_SUBVTT_INDEX (binfo) = *index;
7583 /* Add the address of the primary vtable for the complete object. */
7584 init = binfo_ctor_vtable (binfo);
7585 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7588 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7589 BINFO_VPTR_INDEX (binfo) = *index;
7591 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7593 /* Recursively add the secondary VTTs for non-virtual bases. */
7594 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7595 if (!BINFO_VIRTUAL_P (b))
7596 build_vtt_inits (b, t, inits, index);
7598 /* Add secondary virtual pointers for all subobjects of BINFO with
7599 either virtual bases or reachable along a virtual path, except
7600 subobjects that are non-virtual primary bases. */
7601 data.top_level_p = top_level_p;
7602 data.index = *index;
7603 data.inits = *inits;
7604 data.type_being_constructed = BINFO_TYPE (binfo);
7606 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7608 *index = data.index;
7610 /* data.inits might have grown as we added secondary virtual pointers.
7611 Make sure our caller knows about the new vector. */
7612 *inits = data.inits;
7615 /* Add the secondary VTTs for virtual bases in inheritance graph
7617 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7619 if (!BINFO_VIRTUAL_P (b))
7622 build_vtt_inits (b, t, inits, index);
7625 /* Remove the ctor vtables we created. */
7626 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7629 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7630 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7633 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7635 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7637 /* We don't care about bases that don't have vtables. */
7638 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7639 return dfs_skip_bases;
7641 /* We're only interested in proper subobjects of the type being
7643 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7646 /* We're only interested in bases with virtual bases or reachable
7647 via a virtual path from the type being constructed. */
7648 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7649 || binfo_via_virtual (binfo, data->type_being_constructed)))
7650 return dfs_skip_bases;
7652 /* We're not interested in non-virtual primary bases. */
7653 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7656 /* Record the index where this secondary vptr can be found. */
7657 if (data->top_level_p)
7659 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7660 BINFO_VPTR_INDEX (binfo) = data->index;
7662 if (BINFO_VIRTUAL_P (binfo))
7664 /* It's a primary virtual base, and this is not a
7665 construction vtable. Find the base this is primary of in
7666 the inheritance graph, and use that base's vtable
7668 while (BINFO_PRIMARY_P (binfo))
7669 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7673 /* Add the initializer for the secondary vptr itself. */
7674 CONSTRUCTOR_APPEND_ELT (data->inits, NULL_TREE, binfo_ctor_vtable (binfo));
7676 /* Advance the vtt index. */
7677 data->index = size_binop (PLUS_EXPR, data->index,
7678 TYPE_SIZE_UNIT (ptr_type_node));
7683 /* Called from build_vtt_inits via dfs_walk. After building
7684 constructor vtables and generating the sub-vtt from them, we need
7685 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7686 binfo of the base whose sub vtt was generated. */
7689 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7691 tree vtable = BINFO_VTABLE (binfo);
7693 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7694 /* If this class has no vtable, none of its bases do. */
7695 return dfs_skip_bases;
7698 /* This might be a primary base, so have no vtable in this
7702 /* If we scribbled the construction vtable vptr into BINFO, clear it
7704 if (TREE_CODE (vtable) == TREE_LIST
7705 && (TREE_PURPOSE (vtable) == (tree) data))
7706 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7711 /* Build the construction vtable group for BINFO which is in the
7712 hierarchy dominated by T. */
7715 build_ctor_vtbl_group (tree binfo, tree t)
7721 VEC(constructor_elt,gc) *v;
7723 /* See if we've already created this construction vtable group. */
7724 id = mangle_ctor_vtbl_for_type (t, binfo);
7725 if (IDENTIFIER_GLOBAL_VALUE (id))
7728 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7729 /* Build a version of VTBL (with the wrong type) for use in
7730 constructing the addresses of secondary vtables in the
7731 construction vtable group. */
7732 vtbl = build_vtable (t, id, ptr_type_node);
7733 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7736 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7737 binfo, vtbl, t, &v);
7739 /* Add the vtables for each of our virtual bases using the vbase in T
7741 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7743 vbase = TREE_CHAIN (vbase))
7747 if (!BINFO_VIRTUAL_P (vbase))
7749 b = copied_binfo (vbase, binfo);
7751 accumulate_vtbl_inits (b, vbase, binfo, vtbl, t, &v);
7754 /* Figure out the type of the construction vtable. */
7755 type = build_array_of_n_type (vtable_entry_type,
7756 VEC_length (constructor_elt, v));
7758 TREE_TYPE (vtbl) = type;
7759 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7760 layout_decl (vtbl, 0);
7762 /* Initialize the construction vtable. */
7763 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7764 initialize_artificial_var (vtbl, v);
7765 dump_vtable (t, binfo, vtbl);
7768 /* Add the vtbl initializers for BINFO (and its bases other than
7769 non-virtual primaries) to the list of INITS. BINFO is in the
7770 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7771 the constructor the vtbl inits should be accumulated for. (If this
7772 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7773 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7774 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7775 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7776 but are not necessarily the same in terms of layout. */
7779 accumulate_vtbl_inits (tree binfo,
7784 VEC(constructor_elt,gc) **inits)
7788 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7790 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7792 /* If it doesn't have a vptr, we don't do anything. */
7793 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7796 /* If we're building a construction vtable, we're not interested in
7797 subobjects that don't require construction vtables. */
7799 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7800 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7803 /* Build the initializers for the BINFO-in-T vtable. */
7804 dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, vtbl, t, inits);
7806 /* Walk the BINFO and its bases. We walk in preorder so that as we
7807 initialize each vtable we can figure out at what offset the
7808 secondary vtable lies from the primary vtable. We can't use
7809 dfs_walk here because we need to iterate through bases of BINFO
7810 and RTTI_BINFO simultaneously. */
7811 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7813 /* Skip virtual bases. */
7814 if (BINFO_VIRTUAL_P (base_binfo))
7816 accumulate_vtbl_inits (base_binfo,
7817 BINFO_BASE_BINFO (orig_binfo, i),
7818 rtti_binfo, vtbl, t,
7823 /* Called from accumulate_vtbl_inits. Adds the initializers for the
7824 BINFO vtable to L. */
7827 dfs_accumulate_vtbl_inits (tree binfo,
7832 VEC(constructor_elt,gc) **l)
7834 tree vtbl = NULL_TREE;
7835 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7839 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7841 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7842 primary virtual base. If it is not the same primary in
7843 the hierarchy of T, we'll need to generate a ctor vtable
7844 for it, to place at its location in T. If it is the same
7845 primary, we still need a VTT entry for the vtable, but it
7846 should point to the ctor vtable for the base it is a
7847 primary for within the sub-hierarchy of RTTI_BINFO.
7849 There are three possible cases:
7851 1) We are in the same place.
7852 2) We are a primary base within a lost primary virtual base of
7854 3) We are primary to something not a base of RTTI_BINFO. */
7857 tree last = NULL_TREE;
7859 /* First, look through the bases we are primary to for RTTI_BINFO
7860 or a virtual base. */
7862 while (BINFO_PRIMARY_P (b))
7864 b = BINFO_INHERITANCE_CHAIN (b);
7866 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7869 /* If we run out of primary links, keep looking down our
7870 inheritance chain; we might be an indirect primary. */
7871 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7872 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7876 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7877 base B and it is a base of RTTI_BINFO, this is case 2. In
7878 either case, we share our vtable with LAST, i.e. the
7879 derived-most base within B of which we are a primary. */
7881 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7882 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7883 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7884 binfo_ctor_vtable after everything's been set up. */
7887 /* Otherwise, this is case 3 and we get our own. */
7889 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7892 n_inits = VEC_length (constructor_elt, *l);
7899 /* Add the initializer for this vtable. */
7900 build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7901 &non_fn_entries, l);
7903 /* Figure out the position to which the VPTR should point. */
7904 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, orig_vtbl);
7905 index = size_binop (MULT_EXPR,
7906 TYPE_SIZE_UNIT (vtable_entry_type),
7907 size_int (non_fn_entries + n_inits));
7908 vtbl = fold_build_pointer_plus (vtbl, index);
7912 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7913 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7914 straighten this out. */
7915 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7916 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7917 /* Throw away any unneeded intializers. */
7918 VEC_truncate (constructor_elt, *l, n_inits);
7920 /* For an ordinary vtable, set BINFO_VTABLE. */
7921 BINFO_VTABLE (binfo) = vtbl;
7924 static GTY(()) tree abort_fndecl_addr;
7926 /* Construct the initializer for BINFO's virtual function table. BINFO
7927 is part of the hierarchy dominated by T. If we're building a
7928 construction vtable, the ORIG_BINFO is the binfo we should use to
7929 find the actual function pointers to put in the vtable - but they
7930 can be overridden on the path to most-derived in the graph that
7931 ORIG_BINFO belongs. Otherwise,
7932 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7933 BINFO that should be indicated by the RTTI information in the
7934 vtable; it will be a base class of T, rather than T itself, if we
7935 are building a construction vtable.
7937 The value returned is a TREE_LIST suitable for wrapping in a
7938 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7939 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7940 number of non-function entries in the vtable.
7942 It might seem that this function should never be called with a
7943 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7944 base is always subsumed by a derived class vtable. However, when
7945 we are building construction vtables, we do build vtables for
7946 primary bases; we need these while the primary base is being
7950 build_vtbl_initializer (tree binfo,
7954 int* non_fn_entries_p,
7955 VEC(constructor_elt,gc) **inits)
7961 VEC(tree,gc) *vbases;
7964 /* Initialize VID. */
7965 memset (&vid, 0, sizeof (vid));
7968 vid.rtti_binfo = rtti_binfo;
7969 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7970 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7971 vid.generate_vcall_entries = true;
7972 /* The first vbase or vcall offset is at index -3 in the vtable. */
7973 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7975 /* Add entries to the vtable for RTTI. */
7976 build_rtti_vtbl_entries (binfo, &vid);
7978 /* Create an array for keeping track of the functions we've
7979 processed. When we see multiple functions with the same
7980 signature, we share the vcall offsets. */
7981 vid.fns = VEC_alloc (tree, gc, 32);
7982 /* Add the vcall and vbase offset entries. */
7983 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7985 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7986 build_vbase_offset_vtbl_entries. */
7987 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7988 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7989 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7991 /* If the target requires padding between data entries, add that now. */
7992 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7994 int n_entries = VEC_length (constructor_elt, vid.inits);
7996 VEC_safe_grow (constructor_elt, gc, vid.inits,
7997 TARGET_VTABLE_DATA_ENTRY_DISTANCE * n_entries);
7999 /* Move data entries into their new positions and add padding
8000 after the new positions. Iterate backwards so we don't
8001 overwrite entries that we would need to process later. */
8002 for (ix = n_entries - 1;
8003 VEC_iterate (constructor_elt, vid.inits, ix, e);
8007 int new_position = (TARGET_VTABLE_DATA_ENTRY_DISTANCE * ix
8008 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE - 1));
8010 VEC_replace (constructor_elt, vid.inits, new_position, e);
8012 for (j = 1; j < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++j)
8014 constructor_elt *f = VEC_index (constructor_elt, vid.inits,
8016 f->index = NULL_TREE;
8017 f->value = build1 (NOP_EXPR, vtable_entry_type,
8023 if (non_fn_entries_p)
8024 *non_fn_entries_p = VEC_length (constructor_elt, vid.inits);
8026 /* The initializers for virtual functions were built up in reverse
8027 order. Straighten them out and add them to the running list in one
8029 jx = VEC_length (constructor_elt, *inits);
8030 VEC_safe_grow (constructor_elt, gc, *inits,
8031 (jx + VEC_length (constructor_elt, vid.inits)));
8033 for (ix = VEC_length (constructor_elt, vid.inits) - 1;
8034 VEC_iterate (constructor_elt, vid.inits, ix, e);
8036 VEC_replace (constructor_elt, *inits, jx, e);
8038 /* Go through all the ordinary virtual functions, building up
8040 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
8044 tree fn, fn_original;
8045 tree init = NULL_TREE;
8049 if (DECL_THUNK_P (fn))
8051 if (!DECL_NAME (fn))
8053 if (THUNK_ALIAS (fn))
8055 fn = THUNK_ALIAS (fn);
8058 fn_original = THUNK_TARGET (fn);
8061 /* If the only definition of this function signature along our
8062 primary base chain is from a lost primary, this vtable slot will
8063 never be used, so just zero it out. This is important to avoid
8064 requiring extra thunks which cannot be generated with the function.
8066 We first check this in update_vtable_entry_for_fn, so we handle
8067 restored primary bases properly; we also need to do it here so we
8068 zero out unused slots in ctor vtables, rather than filling them
8069 with erroneous values (though harmless, apart from relocation
8071 if (BV_LOST_PRIMARY (v))
8072 init = size_zero_node;
8076 /* Pull the offset for `this', and the function to call, out of
8078 delta = BV_DELTA (v);
8079 vcall_index = BV_VCALL_INDEX (v);
8081 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
8082 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
8084 /* You can't call an abstract virtual function; it's abstract.
8085 So, we replace these functions with __pure_virtual. */
8086 if (DECL_PURE_VIRTUAL_P (fn_original))
8089 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8091 if (abort_fndecl_addr == NULL)
8093 = fold_convert (vfunc_ptr_type_node,
8094 build_fold_addr_expr (fn));
8095 init = abort_fndecl_addr;
8100 if (!integer_zerop (delta) || vcall_index)
8102 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
8103 if (!DECL_NAME (fn))
8106 /* Take the address of the function, considering it to be of an
8107 appropriate generic type. */
8108 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8109 init = fold_convert (vfunc_ptr_type_node,
8110 build_fold_addr_expr (fn));
8114 /* And add it to the chain of initializers. */
8115 if (TARGET_VTABLE_USES_DESCRIPTORS)
8118 if (init == size_zero_node)
8119 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8120 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8122 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8124 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
8125 fn, build_int_cst (NULL_TREE, i));
8126 TREE_CONSTANT (fdesc) = 1;
8128 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, fdesc);
8132 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8136 /* Adds to vid->inits the initializers for the vbase and vcall
8137 offsets in BINFO, which is in the hierarchy dominated by T. */
8140 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
8144 /* If this is a derived class, we must first create entries
8145 corresponding to the primary base class. */
8146 b = get_primary_binfo (binfo);
8148 build_vcall_and_vbase_vtbl_entries (b, vid);
8150 /* Add the vbase entries for this base. */
8151 build_vbase_offset_vtbl_entries (binfo, vid);
8152 /* Add the vcall entries for this base. */
8153 build_vcall_offset_vtbl_entries (binfo, vid);
8156 /* Returns the initializers for the vbase offset entries in the vtable
8157 for BINFO (which is part of the class hierarchy dominated by T), in
8158 reverse order. VBASE_OFFSET_INDEX gives the vtable index
8159 where the next vbase offset will go. */
8162 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8166 tree non_primary_binfo;
8168 /* If there are no virtual baseclasses, then there is nothing to
8170 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
8175 /* We might be a primary base class. Go up the inheritance hierarchy
8176 until we find the most derived class of which we are a primary base:
8177 it is the offset of that which we need to use. */
8178 non_primary_binfo = binfo;
8179 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8183 /* If we have reached a virtual base, then it must be a primary
8184 base (possibly multi-level) of vid->binfo, or we wouldn't
8185 have called build_vcall_and_vbase_vtbl_entries for it. But it
8186 might be a lost primary, so just skip down to vid->binfo. */
8187 if (BINFO_VIRTUAL_P (non_primary_binfo))
8189 non_primary_binfo = vid->binfo;
8193 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8194 if (get_primary_binfo (b) != non_primary_binfo)
8196 non_primary_binfo = b;
8199 /* Go through the virtual bases, adding the offsets. */
8200 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
8202 vbase = TREE_CHAIN (vbase))
8207 if (!BINFO_VIRTUAL_P (vbase))
8210 /* Find the instance of this virtual base in the complete
8212 b = copied_binfo (vbase, binfo);
8214 /* If we've already got an offset for this virtual base, we
8215 don't need another one. */
8216 if (BINFO_VTABLE_PATH_MARKED (b))
8218 BINFO_VTABLE_PATH_MARKED (b) = 1;
8220 /* Figure out where we can find this vbase offset. */
8221 delta = size_binop (MULT_EXPR,
8224 TYPE_SIZE_UNIT (vtable_entry_type)));
8225 if (vid->primary_vtbl_p)
8226 BINFO_VPTR_FIELD (b) = delta;
8228 if (binfo != TYPE_BINFO (t))
8229 /* The vbase offset had better be the same. */
8230 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
8232 /* The next vbase will come at a more negative offset. */
8233 vid->index = size_binop (MINUS_EXPR, vid->index,
8234 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8236 /* The initializer is the delta from BINFO to this virtual base.
8237 The vbase offsets go in reverse inheritance-graph order, and
8238 we are walking in inheritance graph order so these end up in
8240 delta = size_diffop_loc (input_location,
8241 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
8243 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE,
8244 fold_build1_loc (input_location, NOP_EXPR,
8245 vtable_entry_type, delta));
8249 /* Adds the initializers for the vcall offset entries in the vtable
8250 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
8254 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8256 /* We only need these entries if this base is a virtual base. We
8257 compute the indices -- but do not add to the vtable -- when
8258 building the main vtable for a class. */
8259 if (binfo == TYPE_BINFO (vid->derived)
8260 || (BINFO_VIRTUAL_P (binfo)
8261 /* If BINFO is RTTI_BINFO, then (since BINFO does not
8262 correspond to VID->DERIVED), we are building a primary
8263 construction virtual table. Since this is a primary
8264 virtual table, we do not need the vcall offsets for
8266 && binfo != vid->rtti_binfo))
8268 /* We need a vcall offset for each of the virtual functions in this
8269 vtable. For example:
8271 class A { virtual void f (); };
8272 class B1 : virtual public A { virtual void f (); };
8273 class B2 : virtual public A { virtual void f (); };
8274 class C: public B1, public B2 { virtual void f (); };
8276 A C object has a primary base of B1, which has a primary base of A. A
8277 C also has a secondary base of B2, which no longer has a primary base
8278 of A. So the B2-in-C construction vtable needs a secondary vtable for
8279 A, which will adjust the A* to a B2* to call f. We have no way of
8280 knowing what (or even whether) this offset will be when we define B2,
8281 so we store this "vcall offset" in the A sub-vtable and look it up in
8282 a "virtual thunk" for B2::f.
8284 We need entries for all the functions in our primary vtable and
8285 in our non-virtual bases' secondary vtables. */
8287 /* If we are just computing the vcall indices -- but do not need
8288 the actual entries -- not that. */
8289 if (!BINFO_VIRTUAL_P (binfo))
8290 vid->generate_vcall_entries = false;
8291 /* Now, walk through the non-virtual bases, adding vcall offsets. */
8292 add_vcall_offset_vtbl_entries_r (binfo, vid);
8296 /* Build vcall offsets, starting with those for BINFO. */
8299 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
8305 /* Don't walk into virtual bases -- except, of course, for the
8306 virtual base for which we are building vcall offsets. Any
8307 primary virtual base will have already had its offsets generated
8308 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8309 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
8312 /* If BINFO has a primary base, process it first. */
8313 primary_binfo = get_primary_binfo (binfo);
8315 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
8317 /* Add BINFO itself to the list. */
8318 add_vcall_offset_vtbl_entries_1 (binfo, vid);
8320 /* Scan the non-primary bases of BINFO. */
8321 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8322 if (base_binfo != primary_binfo)
8323 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
8326 /* Called from build_vcall_offset_vtbl_entries_r. */
8329 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
8331 /* Make entries for the rest of the virtuals. */
8332 if (abi_version_at_least (2))
8336 /* The ABI requires that the methods be processed in declaration
8337 order. G++ 3.2 used the order in the vtable. */
8338 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
8340 orig_fn = DECL_CHAIN (orig_fn))
8341 if (DECL_VINDEX (orig_fn))
8342 add_vcall_offset (orig_fn, binfo, vid);
8346 tree derived_virtuals;
8349 /* If BINFO is a primary base, the most derived class which has
8350 BINFO as a primary base; otherwise, just BINFO. */
8351 tree non_primary_binfo;
8353 /* We might be a primary base class. Go up the inheritance hierarchy
8354 until we find the most derived class of which we are a primary base:
8355 it is the BINFO_VIRTUALS there that we need to consider. */
8356 non_primary_binfo = binfo;
8357 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8361 /* If we have reached a virtual base, then it must be vid->vbase,
8362 because we ignore other virtual bases in
8363 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8364 base (possibly multi-level) of vid->binfo, or we wouldn't
8365 have called build_vcall_and_vbase_vtbl_entries for it. But it
8366 might be a lost primary, so just skip down to vid->binfo. */
8367 if (BINFO_VIRTUAL_P (non_primary_binfo))
8369 gcc_assert (non_primary_binfo == vid->vbase);
8370 non_primary_binfo = vid->binfo;
8374 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8375 if (get_primary_binfo (b) != non_primary_binfo)
8377 non_primary_binfo = b;
8380 if (vid->ctor_vtbl_p)
8381 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8382 where rtti_binfo is the most derived type. */
8384 = original_binfo (non_primary_binfo, vid->rtti_binfo);
8386 for (base_virtuals = BINFO_VIRTUALS (binfo),
8387 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
8388 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
8390 base_virtuals = TREE_CHAIN (base_virtuals),
8391 derived_virtuals = TREE_CHAIN (derived_virtuals),
8392 orig_virtuals = TREE_CHAIN (orig_virtuals))
8396 /* Find the declaration that originally caused this function to
8397 be present in BINFO_TYPE (binfo). */
8398 orig_fn = BV_FN (orig_virtuals);
8400 /* When processing BINFO, we only want to generate vcall slots for
8401 function slots introduced in BINFO. So don't try to generate
8402 one if the function isn't even defined in BINFO. */
8403 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
8406 add_vcall_offset (orig_fn, binfo, vid);
8411 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8414 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
8420 /* If there is already an entry for a function with the same
8421 signature as FN, then we do not need a second vcall offset.
8422 Check the list of functions already present in the derived
8424 FOR_EACH_VEC_ELT (tree, vid->fns, i, derived_entry)
8426 if (same_signature_p (derived_entry, orig_fn)
8427 /* We only use one vcall offset for virtual destructors,
8428 even though there are two virtual table entries. */
8429 || (DECL_DESTRUCTOR_P (derived_entry)
8430 && DECL_DESTRUCTOR_P (orig_fn)))
8434 /* If we are building these vcall offsets as part of building
8435 the vtable for the most derived class, remember the vcall
8437 if (vid->binfo == TYPE_BINFO (vid->derived))
8439 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
8440 CLASSTYPE_VCALL_INDICES (vid->derived),
8442 elt->purpose = orig_fn;
8443 elt->value = vid->index;
8446 /* The next vcall offset will be found at a more negative
8448 vid->index = size_binop (MINUS_EXPR, vid->index,
8449 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8451 /* Keep track of this function. */
8452 VEC_safe_push (tree, gc, vid->fns, orig_fn);
8454 if (vid->generate_vcall_entries)
8459 /* Find the overriding function. */
8460 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8461 if (fn == error_mark_node)
8462 vcall_offset = build_zero_cst (vtable_entry_type);
8465 base = TREE_VALUE (fn);
8467 /* The vbase we're working on is a primary base of
8468 vid->binfo. But it might be a lost primary, so its
8469 BINFO_OFFSET might be wrong, so we just use the
8470 BINFO_OFFSET from vid->binfo. */
8471 vcall_offset = size_diffop_loc (input_location,
8472 BINFO_OFFSET (base),
8473 BINFO_OFFSET (vid->binfo));
8474 vcall_offset = fold_build1_loc (input_location,
8475 NOP_EXPR, vtable_entry_type,
8478 /* Add the initializer to the vtable. */
8479 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, vcall_offset);
8483 /* Return vtbl initializers for the RTTI entries corresponding to the
8484 BINFO's vtable. The RTTI entries should indicate the object given
8485 by VID->rtti_binfo. */
8488 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8496 t = BINFO_TYPE (vid->rtti_binfo);
8498 /* To find the complete object, we will first convert to our most
8499 primary base, and then add the offset in the vtbl to that value. */
8501 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8502 && !BINFO_LOST_PRIMARY_P (b))
8506 primary_base = get_primary_binfo (b);
8507 gcc_assert (BINFO_PRIMARY_P (primary_base)
8508 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8511 offset = size_diffop_loc (input_location,
8512 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8514 /* The second entry is the address of the typeinfo object. */
8516 decl = build_address (get_tinfo_decl (t));
8518 decl = integer_zero_node;
8520 /* Convert the declaration to a type that can be stored in the
8522 init = build_nop (vfunc_ptr_type_node, decl);
8523 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8525 /* Add the offset-to-top entry. It comes earlier in the vtable than
8526 the typeinfo entry. Convert the offset to look like a
8527 function pointer, so that we can put it in the vtable. */
8528 init = build_nop (vfunc_ptr_type_node, offset);
8529 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8532 #include "gt-cp-class.h"