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
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"
41 /* The number of nested classes being processed. If we are not in the
42 scope of any class, this is zero. */
44 int current_class_depth;
46 /* In order to deal with nested classes, we keep a stack of classes.
47 The topmost entry is the innermost class, and is the entry at index
48 CURRENT_CLASS_DEPTH */
50 typedef struct class_stack_node {
51 /* The name of the class. */
54 /* The _TYPE node for the class. */
57 /* The access specifier pending for new declarations in the scope of
61 /* If were defining TYPE, the names used in this class. */
62 splay_tree names_used;
64 /* Nonzero if this class is no longer open, because of a call to
67 }* class_stack_node_t;
69 typedef struct vtbl_init_data_s
71 /* The base for which we're building initializers. */
73 /* The type of the most-derived type. */
75 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
76 unless ctor_vtbl_p is true. */
78 /* The negative-index vtable initializers built up so far. These
79 are in order from least negative index to most negative index. */
80 VEC(constructor_elt,gc) *inits;
81 /* The binfo for the virtual base for which we're building
82 vcall offset initializers. */
84 /* The functions in vbase for which we have already provided vcall
87 /* The vtable index of the next vcall or vbase offset. */
89 /* Nonzero if we are building the initializer for the primary
92 /* Nonzero if we are building the initializer for a construction
95 /* True when adding vcall offset entries to the vtable. False when
96 merely computing the indices. */
97 bool generate_vcall_entries;
100 /* The type of a function passed to walk_subobject_offsets. */
101 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
103 /* The stack itself. This is a dynamically resized array. The
104 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
105 static int current_class_stack_size;
106 static class_stack_node_t current_class_stack;
108 /* The size of the largest empty class seen in this translation unit. */
109 static GTY (()) tree sizeof_biggest_empty_class;
111 /* An array of all local classes present in this translation unit, in
112 declaration order. */
113 VEC(tree,gc) *local_classes;
115 static tree get_vfield_name (tree);
116 static void finish_struct_anon (tree);
117 static tree get_vtable_name (tree);
118 static tree get_basefndecls (tree, tree);
119 static int build_primary_vtable (tree, tree);
120 static int build_secondary_vtable (tree);
121 static void finish_vtbls (tree);
122 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
123 static void finish_struct_bits (tree);
124 static int alter_access (tree, tree, tree);
125 static void handle_using_decl (tree, tree);
126 static tree dfs_modify_vtables (tree, void *);
127 static tree modify_all_vtables (tree, tree);
128 static void determine_primary_bases (tree);
129 static void finish_struct_methods (tree);
130 static void maybe_warn_about_overly_private_class (tree);
131 static int method_name_cmp (const void *, const void *);
132 static int resort_method_name_cmp (const void *, const void *);
133 static void add_implicitly_declared_members (tree, int, int);
134 static tree fixed_type_or_null (tree, int *, int *);
135 static tree build_simple_base_path (tree expr, tree binfo);
136 static tree build_vtbl_ref_1 (tree, tree);
137 static void build_vtbl_initializer (tree, tree, tree, tree, int *,
138 VEC(constructor_elt,gc) **);
139 static int count_fields (tree);
140 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
141 static bool check_bitfield_decl (tree);
142 static void check_field_decl (tree, tree, int *, int *, int *);
143 static void check_field_decls (tree, tree *, int *, int *);
144 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
145 static void build_base_fields (record_layout_info, splay_tree, tree *);
146 static void check_methods (tree);
147 static void remove_zero_width_bit_fields (tree);
148 static void check_bases (tree, int *, int *);
149 static void check_bases_and_members (tree);
150 static tree create_vtable_ptr (tree, tree *);
151 static void include_empty_classes (record_layout_info);
152 static void layout_class_type (tree, tree *);
153 static void propagate_binfo_offsets (tree, tree);
154 static void layout_virtual_bases (record_layout_info, splay_tree);
155 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
156 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
157 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
158 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
159 static void add_vcall_offset (tree, tree, vtbl_init_data *);
160 static void layout_vtable_decl (tree, int);
161 static tree dfs_find_final_overrider_pre (tree, void *);
162 static tree dfs_find_final_overrider_post (tree, void *);
163 static tree find_final_overrider (tree, tree, tree);
164 static int make_new_vtable (tree, tree);
165 static tree get_primary_binfo (tree);
166 static int maybe_indent_hierarchy (FILE *, int, int);
167 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
168 static void dump_class_hierarchy (tree);
169 static void dump_class_hierarchy_1 (FILE *, int, tree);
170 static void dump_array (FILE *, tree);
171 static void dump_vtable (tree, tree, tree);
172 static void dump_vtt (tree, tree);
173 static void dump_thunk (FILE *, int, tree);
174 static tree build_vtable (tree, tree, tree);
175 static void initialize_vtable (tree, VEC(constructor_elt,gc) *);
176 static void layout_nonempty_base_or_field (record_layout_info,
177 tree, tree, splay_tree);
178 static tree end_of_class (tree, int);
179 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
180 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree,
181 VEC(constructor_elt,gc) **);
182 static void dfs_accumulate_vtbl_inits (tree, tree, tree, tree, tree,
183 VEC(constructor_elt,gc) **);
184 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
185 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
186 static void clone_constructors_and_destructors (tree);
187 static tree build_clone (tree, tree);
188 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
189 static void build_ctor_vtbl_group (tree, tree);
190 static void build_vtt (tree);
191 static tree binfo_ctor_vtable (tree);
192 static void build_vtt_inits (tree, tree, VEC(constructor_elt,gc) **, tree *);
193 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
194 static tree dfs_fixup_binfo_vtbls (tree, void *);
195 static int record_subobject_offset (tree, tree, splay_tree);
196 static int check_subobject_offset (tree, tree, splay_tree);
197 static int walk_subobject_offsets (tree, subobject_offset_fn,
198 tree, splay_tree, tree, int);
199 static void record_subobject_offsets (tree, tree, splay_tree, bool);
200 static int layout_conflict_p (tree, tree, splay_tree, int);
201 static int splay_tree_compare_integer_csts (splay_tree_key k1,
203 static void warn_about_ambiguous_bases (tree);
204 static bool type_requires_array_cookie (tree);
205 static bool contains_empty_class_p (tree);
206 static bool base_derived_from (tree, tree);
207 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
208 static tree end_of_base (tree);
209 static tree get_vcall_index (tree, tree);
211 /* Variables shared between class.c and call.c. */
213 #ifdef GATHER_STATISTICS
215 int n_vtable_entries = 0;
216 int n_vtable_searches = 0;
217 int n_vtable_elems = 0;
218 int n_convert_harshness = 0;
219 int n_compute_conversion_costs = 0;
220 int n_inner_fields_searched = 0;
223 /* Convert to or from a base subobject. EXPR is an expression of type
224 `A' or `A*', an expression of type `B' or `B*' is returned. To
225 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
226 the B base instance within A. To convert base A to derived B, CODE
227 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
228 In this latter case, A must not be a morally virtual base of B.
229 NONNULL is true if EXPR is known to be non-NULL (this is only
230 needed when EXPR is of pointer type). CV qualifiers are preserved
234 build_base_path (enum tree_code code,
239 tree v_binfo = NULL_TREE;
240 tree d_binfo = NULL_TREE;
244 tree null_test = NULL;
245 tree ptr_target_type;
247 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
248 bool has_empty = false;
251 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
252 return error_mark_node;
254 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
257 if (is_empty_class (BINFO_TYPE (probe)))
259 if (!v_binfo && BINFO_VIRTUAL_P (probe))
263 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
265 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
267 gcc_assert ((code == MINUS_EXPR
268 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
269 || (code == PLUS_EXPR
270 && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
272 if (binfo == d_binfo)
276 if (code == MINUS_EXPR && v_binfo)
278 error ("cannot convert from base %qT to derived type %qT via virtual base %qT",
279 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
280 return error_mark_node;
284 /* This must happen before the call to save_expr. */
285 expr = cp_build_addr_expr (expr, tf_warning_or_error);
287 expr = mark_rvalue_use (expr);
289 offset = BINFO_OFFSET (binfo);
290 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
291 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
293 /* Do we need to look in the vtable for the real offset? */
294 virtual_access = (v_binfo && fixed_type_p <= 0);
296 /* Don't bother with the calculations inside sizeof; they'll ICE if the
297 source type is incomplete and the pointer value doesn't matter. */
298 if (cp_unevaluated_operand != 0)
300 expr = build_nop (build_pointer_type (target_type), expr);
302 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
306 /* Do we need to check for a null pointer? */
307 if (want_pointer && !nonnull)
309 /* If we know the conversion will not actually change the value
310 of EXPR, then we can avoid testing the expression for NULL.
311 We have to avoid generating a COMPONENT_REF for a base class
312 field, because other parts of the compiler know that such
313 expressions are always non-NULL. */
314 if (!virtual_access && integer_zerop (offset))
317 /* TARGET_TYPE has been extracted from BINFO, and, is
318 therefore always cv-unqualified. Extract the
319 cv-qualifiers from EXPR so that the expression returned
320 matches the input. */
321 class_type = TREE_TYPE (TREE_TYPE (expr));
323 = cp_build_qualified_type (target_type,
324 cp_type_quals (class_type));
325 return build_nop (build_pointer_type (target_type), expr);
327 null_test = error_mark_node;
330 /* Protect against multiple evaluation if necessary. */
331 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
332 expr = save_expr (expr);
334 /* Now that we've saved expr, build the real null test. */
337 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
338 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
342 /* If this is a simple base reference, express it as a COMPONENT_REF. */
343 if (code == PLUS_EXPR && !virtual_access
344 /* We don't build base fields for empty bases, and they aren't very
345 interesting to the optimizers anyway. */
348 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
349 expr = build_simple_base_path (expr, binfo);
351 expr = build_address (expr);
352 target_type = TREE_TYPE (expr);
358 /* Going via virtual base V_BINFO. We need the static offset
359 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
360 V_BINFO. That offset is an entry in D_BINFO's vtable. */
363 if (fixed_type_p < 0 && in_base_initializer)
365 /* In a base member initializer, we cannot rely on the
366 vtable being set up. We have to indirect via the
370 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
371 t = build_pointer_type (t);
372 v_offset = convert (t, current_vtt_parm);
373 v_offset = cp_build_indirect_ref (v_offset, RO_NULL,
374 tf_warning_or_error);
377 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, RO_NULL,
378 tf_warning_or_error),
379 TREE_TYPE (TREE_TYPE (expr)));
381 v_offset = build2 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
382 v_offset, fold_convert (sizetype, BINFO_VPTR_FIELD (v_binfo)));
383 v_offset = build1 (NOP_EXPR,
384 build_pointer_type (ptrdiff_type_node),
386 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, tf_warning_or_error);
387 TREE_CONSTANT (v_offset) = 1;
389 offset = convert_to_integer (ptrdiff_type_node,
390 size_diffop_loc (input_location, offset,
391 BINFO_OFFSET (v_binfo)));
393 if (!integer_zerop (offset))
394 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
396 if (fixed_type_p < 0)
397 /* Negative fixed_type_p means this is a constructor or destructor;
398 virtual base layout is fixed in in-charge [cd]tors, but not in
400 offset = build3 (COND_EXPR, ptrdiff_type_node,
401 build2 (EQ_EXPR, boolean_type_node,
402 current_in_charge_parm, integer_zero_node),
404 convert_to_integer (ptrdiff_type_node,
405 BINFO_OFFSET (binfo)));
410 target_type = cp_build_qualified_type
411 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
412 ptr_target_type = build_pointer_type (target_type);
414 target_type = ptr_target_type;
416 expr = build1 (NOP_EXPR, ptr_target_type, expr);
418 if (!integer_zerop (offset))
420 offset = fold_convert (sizetype, offset);
421 if (code == MINUS_EXPR)
422 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
423 expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
429 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
433 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
434 build_zero_cst (target_type));
439 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
440 Perform a derived-to-base conversion by recursively building up a
441 sequence of COMPONENT_REFs to the appropriate base fields. */
444 build_simple_base_path (tree expr, tree binfo)
446 tree type = BINFO_TYPE (binfo);
447 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
450 if (d_binfo == NULL_TREE)
454 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
456 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
457 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
458 an lvalue in the front end; only _DECLs and _REFs are lvalues
460 temp = unary_complex_lvalue (ADDR_EXPR, expr);
462 expr = cp_build_indirect_ref (temp, RO_NULL, tf_warning_or_error);
468 expr = build_simple_base_path (expr, d_binfo);
470 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
471 field; field = DECL_CHAIN (field))
472 /* Is this the base field created by build_base_field? */
473 if (TREE_CODE (field) == FIELD_DECL
474 && DECL_FIELD_IS_BASE (field)
475 && TREE_TYPE (field) == type)
477 /* We don't use build_class_member_access_expr here, as that
478 has unnecessary checks, and more importantly results in
479 recursive calls to dfs_walk_once. */
480 int type_quals = cp_type_quals (TREE_TYPE (expr));
482 expr = build3 (COMPONENT_REF,
483 cp_build_qualified_type (type, type_quals),
484 expr, field, NULL_TREE);
485 expr = fold_if_not_in_template (expr);
487 /* Mark the expression const or volatile, as appropriate.
488 Even though we've dealt with the type above, we still have
489 to mark the expression itself. */
490 if (type_quals & TYPE_QUAL_CONST)
491 TREE_READONLY (expr) = 1;
492 if (type_quals & TYPE_QUAL_VOLATILE)
493 TREE_THIS_VOLATILE (expr) = 1;
498 /* Didn't find the base field?!? */
502 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
503 type is a class type or a pointer to a class type. In the former
504 case, TYPE is also a class type; in the latter it is another
505 pointer type. If CHECK_ACCESS is true, an error message is emitted
506 if TYPE is inaccessible. If OBJECT has pointer type, the value is
507 assumed to be non-NULL. */
510 convert_to_base (tree object, tree type, bool check_access, bool nonnull,
511 tsubst_flags_t complain)
517 if (TYPE_PTR_P (TREE_TYPE (object)))
519 object_type = TREE_TYPE (TREE_TYPE (object));
520 type = TREE_TYPE (type);
523 object_type = TREE_TYPE (object);
525 access = check_access ? ba_check : ba_unique;
526 if (!(complain & tf_error))
528 binfo = lookup_base (object_type, type,
531 if (!binfo || binfo == error_mark_node)
532 return error_mark_node;
534 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
537 /* EXPR is an expression with unqualified class type. BASE is a base
538 binfo of that class type. Returns EXPR, converted to the BASE
539 type. This function assumes that EXPR is the most derived class;
540 therefore virtual bases can be found at their static offsets. */
543 convert_to_base_statically (tree expr, tree base)
547 expr_type = TREE_TYPE (expr);
548 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
552 pointer_type = build_pointer_type (expr_type);
554 /* We use fold_build2 and fold_convert below to simplify the trees
555 provided to the optimizers. It is not safe to call these functions
556 when processing a template because they do not handle C++-specific
558 gcc_assert (!processing_template_decl);
559 expr = cp_build_addr_expr (expr, tf_warning_or_error);
560 if (!integer_zerop (BINFO_OFFSET (base)))
561 expr = fold_build2_loc (input_location,
562 POINTER_PLUS_EXPR, pointer_type, expr,
563 fold_convert (sizetype, BINFO_OFFSET (base)));
564 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
565 expr = build_fold_indirect_ref_loc (input_location, expr);
573 build_vfield_ref (tree datum, tree type)
575 tree vfield, vcontext;
577 if (datum == error_mark_node)
578 return error_mark_node;
580 /* First, convert to the requested type. */
581 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
582 datum = convert_to_base (datum, type, /*check_access=*/false,
583 /*nonnull=*/true, tf_warning_or_error);
585 /* Second, the requested type may not be the owner of its own vptr.
586 If not, convert to the base class that owns it. We cannot use
587 convert_to_base here, because VCONTEXT may appear more than once
588 in the inheritance hierarchy of TYPE, and thus direct conversion
589 between the types may be ambiguous. Following the path back up
590 one step at a time via primary bases avoids the problem. */
591 vfield = TYPE_VFIELD (type);
592 vcontext = DECL_CONTEXT (vfield);
593 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
595 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
596 type = TREE_TYPE (datum);
599 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
602 /* Given an object INSTANCE, return an expression which yields the
603 vtable element corresponding to INDEX. There are many special
604 cases for INSTANCE which we take care of here, mainly to avoid
605 creating extra tree nodes when we don't have to. */
608 build_vtbl_ref_1 (tree instance, tree idx)
611 tree vtbl = NULL_TREE;
613 /* Try to figure out what a reference refers to, and
614 access its virtual function table directly. */
617 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
619 tree basetype = non_reference (TREE_TYPE (instance));
621 if (fixed_type && !cdtorp)
623 tree binfo = lookup_base (fixed_type, basetype,
624 ba_unique | ba_quiet, NULL);
626 vtbl = unshare_expr (BINFO_VTABLE (binfo));
630 vtbl = build_vfield_ref (instance, basetype);
632 aref = build_array_ref (input_location, vtbl, idx);
633 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
639 build_vtbl_ref (tree instance, tree idx)
641 tree aref = build_vtbl_ref_1 (instance, idx);
646 /* Given a stable object pointer INSTANCE_PTR, return an expression which
647 yields a function pointer corresponding to vtable element INDEX. */
650 build_vfn_ref (tree instance_ptr, tree idx)
654 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, RO_NULL,
655 tf_warning_or_error),
658 /* When using function descriptors, the address of the
659 vtable entry is treated as a function pointer. */
660 if (TARGET_VTABLE_USES_DESCRIPTORS)
661 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
662 cp_build_addr_expr (aref, tf_warning_or_error));
664 /* Remember this as a method reference, for later devirtualization. */
665 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
670 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
671 for the given TYPE. */
674 get_vtable_name (tree type)
676 return mangle_vtbl_for_type (type);
679 /* DECL is an entity associated with TYPE, like a virtual table or an
680 implicitly generated constructor. Determine whether or not DECL
681 should have external or internal linkage at the object file
682 level. This routine does not deal with COMDAT linkage and other
683 similar complexities; it simply sets TREE_PUBLIC if it possible for
684 entities in other translation units to contain copies of DECL, in
688 set_linkage_according_to_type (tree type, tree decl)
690 /* If TYPE involves a local class in a function with internal
691 linkage, then DECL should have internal linkage too. Other local
692 classes have no linkage -- but if their containing functions
693 have external linkage, it makes sense for DECL to have external
694 linkage too. That will allow template definitions to be merged,
696 if (no_linkage_check (type, /*relaxed_p=*/true))
698 TREE_PUBLIC (decl) = 0;
699 DECL_INTERFACE_KNOWN (decl) = 1;
702 TREE_PUBLIC (decl) = 1;
705 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
706 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
707 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
710 build_vtable (tree class_type, tree name, tree vtable_type)
714 decl = build_lang_decl (VAR_DECL, name, vtable_type);
715 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
716 now to avoid confusion in mangle_decl. */
717 SET_DECL_ASSEMBLER_NAME (decl, name);
718 DECL_CONTEXT (decl) = class_type;
719 DECL_ARTIFICIAL (decl) = 1;
720 TREE_STATIC (decl) = 1;
721 TREE_READONLY (decl) = 1;
722 DECL_VIRTUAL_P (decl) = 1;
723 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
724 DECL_VTABLE_OR_VTT_P (decl) = 1;
725 /* At one time the vtable info was grabbed 2 words at a time. This
726 fails on sparc unless you have 8-byte alignment. (tiemann) */
727 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
729 set_linkage_according_to_type (class_type, decl);
730 /* The vtable has not been defined -- yet. */
731 DECL_EXTERNAL (decl) = 1;
732 DECL_NOT_REALLY_EXTERN (decl) = 1;
734 /* Mark the VAR_DECL node representing the vtable itself as a
735 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
736 is rather important that such things be ignored because any
737 effort to actually generate DWARF for them will run into
738 trouble when/if we encounter code like:
741 struct S { virtual void member (); };
743 because the artificial declaration of the vtable itself (as
744 manufactured by the g++ front end) will say that the vtable is
745 a static member of `S' but only *after* the debug output for
746 the definition of `S' has already been output. This causes
747 grief because the DWARF entry for the definition of the vtable
748 will try to refer back to an earlier *declaration* of the
749 vtable as a static member of `S' and there won't be one. We
750 might be able to arrange to have the "vtable static member"
751 attached to the member list for `S' before the debug info for
752 `S' get written (which would solve the problem) but that would
753 require more intrusive changes to the g++ front end. */
754 DECL_IGNORED_P (decl) = 1;
759 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
760 or even complete. If this does not exist, create it. If COMPLETE is
761 nonzero, then complete the definition of it -- that will render it
762 impossible to actually build the vtable, but is useful to get at those
763 which are known to exist in the runtime. */
766 get_vtable_decl (tree type, int complete)
770 if (CLASSTYPE_VTABLES (type))
771 return CLASSTYPE_VTABLES (type);
773 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
774 CLASSTYPE_VTABLES (type) = decl;
778 DECL_EXTERNAL (decl) = 1;
779 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
785 /* Build the primary virtual function table for TYPE. If BINFO is
786 non-NULL, build the vtable starting with the initial approximation
787 that it is the same as the one which is the head of the association
788 list. Returns a nonzero value if a new vtable is actually
792 build_primary_vtable (tree binfo, tree type)
797 decl = get_vtable_decl (type, /*complete=*/0);
801 if (BINFO_NEW_VTABLE_MARKED (binfo))
802 /* We have already created a vtable for this base, so there's
803 no need to do it again. */
806 virtuals = copy_list (BINFO_VIRTUALS (binfo));
807 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
808 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
809 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
813 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
814 virtuals = NULL_TREE;
817 #ifdef GATHER_STATISTICS
819 n_vtable_elems += list_length (virtuals);
822 /* Initialize the association list for this type, based
823 on our first approximation. */
824 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
825 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
826 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
830 /* Give BINFO a new virtual function table which is initialized
831 with a skeleton-copy of its original initialization. The only
832 entry that changes is the `delta' entry, so we can really
833 share a lot of structure.
835 FOR_TYPE is the most derived type which caused this table to
838 Returns nonzero if we haven't met BINFO before.
840 The order in which vtables are built (by calling this function) for
841 an object must remain the same, otherwise a binary incompatibility
845 build_secondary_vtable (tree binfo)
847 if (BINFO_NEW_VTABLE_MARKED (binfo))
848 /* We already created a vtable for this base. There's no need to
852 /* Remember that we've created a vtable for this BINFO, so that we
853 don't try to do so again. */
854 SET_BINFO_NEW_VTABLE_MARKED (binfo);
856 /* Make fresh virtual list, so we can smash it later. */
857 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
859 /* Secondary vtables are laid out as part of the same structure as
860 the primary vtable. */
861 BINFO_VTABLE (binfo) = NULL_TREE;
865 /* Create a new vtable for BINFO which is the hierarchy dominated by
866 T. Return nonzero if we actually created a new vtable. */
869 make_new_vtable (tree t, tree binfo)
871 if (binfo == TYPE_BINFO (t))
872 /* In this case, it is *type*'s vtable we are modifying. We start
873 with the approximation that its vtable is that of the
874 immediate base class. */
875 return build_primary_vtable (binfo, t);
877 /* This is our very own copy of `basetype' to play with. Later,
878 we will fill in all the virtual functions that override the
879 virtual functions in these base classes which are not defined
880 by the current type. */
881 return build_secondary_vtable (binfo);
884 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
885 (which is in the hierarchy dominated by T) list FNDECL as its
886 BV_FN. DELTA is the required constant adjustment from the `this'
887 pointer where the vtable entry appears to the `this' required when
888 the function is actually called. */
891 modify_vtable_entry (tree t,
901 if (fndecl != BV_FN (v)
902 || !tree_int_cst_equal (delta, BV_DELTA (v)))
904 /* We need a new vtable for BINFO. */
905 if (make_new_vtable (t, binfo))
907 /* If we really did make a new vtable, we also made a copy
908 of the BINFO_VIRTUALS list. Now, we have to find the
909 corresponding entry in that list. */
910 *virtuals = BINFO_VIRTUALS (binfo);
911 while (BV_FN (*virtuals) != BV_FN (v))
912 *virtuals = TREE_CHAIN (*virtuals);
916 BV_DELTA (v) = delta;
917 BV_VCALL_INDEX (v) = NULL_TREE;
923 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
924 the USING_DECL naming METHOD. Returns true if the method could be
925 added to the method vec. */
928 add_method (tree type, tree method, tree using_decl)
932 bool template_conv_p = false;
934 VEC(tree,gc) *method_vec;
936 bool insert_p = false;
940 if (method == error_mark_node)
943 complete_p = COMPLETE_TYPE_P (type);
944 conv_p = DECL_CONV_FN_P (method);
946 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
947 && DECL_TEMPLATE_CONV_FN_P (method));
949 method_vec = CLASSTYPE_METHOD_VEC (type);
952 /* Make a new method vector. We start with 8 entries. We must
953 allocate at least two (for constructors and destructors), and
954 we're going to end up with an assignment operator at some
956 method_vec = VEC_alloc (tree, gc, 8);
957 /* Create slots for constructors and destructors. */
958 VEC_quick_push (tree, method_vec, NULL_TREE);
959 VEC_quick_push (tree, method_vec, NULL_TREE);
960 CLASSTYPE_METHOD_VEC (type) = method_vec;
963 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
964 grok_special_member_properties (method);
966 /* Constructors and destructors go in special slots. */
967 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
968 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
969 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
971 slot = CLASSTYPE_DESTRUCTOR_SLOT;
973 if (TYPE_FOR_JAVA (type))
975 if (!DECL_ARTIFICIAL (method))
976 error ("Java class %qT cannot have a destructor", type);
977 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
978 error ("Java class %qT cannot have an implicit non-trivial "
988 /* See if we already have an entry with this name. */
989 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
990 VEC_iterate (tree, method_vec, slot, m);
996 if (TREE_CODE (m) == TEMPLATE_DECL
997 && DECL_TEMPLATE_CONV_FN_P (m))
1001 if (conv_p && !DECL_CONV_FN_P (m))
1003 if (DECL_NAME (m) == DECL_NAME (method))
1009 && !DECL_CONV_FN_P (m)
1010 && DECL_NAME (m) > DECL_NAME (method))
1014 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1016 /* Check to see if we've already got this method. */
1017 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1019 tree fn = OVL_CURRENT (fns);
1025 if (TREE_CODE (fn) != TREE_CODE (method))
1028 /* [over.load] Member function declarations with the
1029 same name and the same parameter types cannot be
1030 overloaded if any of them is a static member
1031 function declaration.
1033 [namespace.udecl] When a using-declaration brings names
1034 from a base class into a derived class scope, member
1035 functions in the derived class override and/or hide member
1036 functions with the same name and parameter types in a base
1037 class (rather than conflicting). */
1038 fn_type = TREE_TYPE (fn);
1039 method_type = TREE_TYPE (method);
1040 parms1 = TYPE_ARG_TYPES (fn_type);
1041 parms2 = TYPE_ARG_TYPES (method_type);
1043 /* Compare the quals on the 'this' parm. Don't compare
1044 the whole types, as used functions are treated as
1045 coming from the using class in overload resolution. */
1046 if (! DECL_STATIC_FUNCTION_P (fn)
1047 && ! DECL_STATIC_FUNCTION_P (method)
1048 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1049 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1050 && (cp_type_quals (TREE_TYPE (TREE_VALUE (parms1)))
1051 != cp_type_quals (TREE_TYPE (TREE_VALUE (parms2)))))
1054 /* For templates, the return type and template parameters
1055 must be identical. */
1056 if (TREE_CODE (fn) == TEMPLATE_DECL
1057 && (!same_type_p (TREE_TYPE (fn_type),
1058 TREE_TYPE (method_type))
1059 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1060 DECL_TEMPLATE_PARMS (method))))
1063 if (! DECL_STATIC_FUNCTION_P (fn))
1064 parms1 = TREE_CHAIN (parms1);
1065 if (! DECL_STATIC_FUNCTION_P (method))
1066 parms2 = TREE_CHAIN (parms2);
1068 if (compparms (parms1, parms2)
1069 && (!DECL_CONV_FN_P (fn)
1070 || same_type_p (TREE_TYPE (fn_type),
1071 TREE_TYPE (method_type))))
1075 if (DECL_CONTEXT (fn) == type)
1076 /* Defer to the local function. */
1078 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1079 error ("repeated using declaration %q+D", using_decl);
1081 error ("using declaration %q+D conflicts with a previous using declaration",
1086 error ("%q+#D cannot be overloaded", method);
1087 error ("with %q+#D", fn);
1090 /* We don't call duplicate_decls here to merge the
1091 declarations because that will confuse things if the
1092 methods have inline definitions. In particular, we
1093 will crash while processing the definitions. */
1098 /* A class should never have more than one destructor. */
1099 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1102 /* Add the new binding. */
1103 overload = build_overload (method, current_fns);
1106 TYPE_HAS_CONVERSION (type) = 1;
1107 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1108 push_class_level_binding (DECL_NAME (method), overload);
1114 /* We only expect to add few methods in the COMPLETE_P case, so
1115 just make room for one more method in that case. */
1117 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1119 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1121 CLASSTYPE_METHOD_VEC (type) = method_vec;
1122 if (slot == VEC_length (tree, method_vec))
1123 VEC_quick_push (tree, method_vec, overload);
1125 VEC_quick_insert (tree, method_vec, slot, overload);
1128 /* Replace the current slot. */
1129 VEC_replace (tree, method_vec, slot, overload);
1133 /* Subroutines of finish_struct. */
1135 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1136 legit, otherwise return 0. */
1139 alter_access (tree t, tree fdecl, tree access)
1143 if (!DECL_LANG_SPECIFIC (fdecl))
1144 retrofit_lang_decl (fdecl);
1146 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1148 elem = purpose_member (t, DECL_ACCESS (fdecl));
1151 if (TREE_VALUE (elem) != access)
1153 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1154 error ("conflicting access specifications for method"
1155 " %q+D, ignored", TREE_TYPE (fdecl));
1157 error ("conflicting access specifications for field %qE, ignored",
1162 /* They're changing the access to the same thing they changed
1163 it to before. That's OK. */
1169 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1170 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1176 /* Process the USING_DECL, which is a member of T. */
1179 handle_using_decl (tree using_decl, tree t)
1181 tree decl = USING_DECL_DECLS (using_decl);
1182 tree name = DECL_NAME (using_decl);
1184 = TREE_PRIVATE (using_decl) ? access_private_node
1185 : TREE_PROTECTED (using_decl) ? access_protected_node
1186 : access_public_node;
1187 tree flist = NULL_TREE;
1190 gcc_assert (!processing_template_decl && decl);
1192 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1195 if (is_overloaded_fn (old_value))
1196 old_value = OVL_CURRENT (old_value);
1198 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1201 old_value = NULL_TREE;
1204 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1206 if (is_overloaded_fn (decl))
1211 else if (is_overloaded_fn (old_value))
1214 /* It's OK to use functions from a base when there are functions with
1215 the same name already present in the current class. */;
1218 error ("%q+D invalid in %q#T", using_decl, t);
1219 error (" because of local method %q+#D with same name",
1220 OVL_CURRENT (old_value));
1224 else if (!DECL_ARTIFICIAL (old_value))
1226 error ("%q+D invalid in %q#T", using_decl, t);
1227 error (" because of local member %q+#D with same name", old_value);
1231 /* Make type T see field decl FDECL with access ACCESS. */
1233 for (; flist; flist = OVL_NEXT (flist))
1235 add_method (t, OVL_CURRENT (flist), using_decl);
1236 alter_access (t, OVL_CURRENT (flist), access);
1239 alter_access (t, decl, access);
1242 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1243 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1244 properties of the bases. */
1247 check_bases (tree t,
1248 int* cant_have_const_ctor_p,
1249 int* no_const_asn_ref_p)
1252 int seen_non_virtual_nearly_empty_base_p;
1255 tree field = NULL_TREE;
1257 seen_non_virtual_nearly_empty_base_p = 0;
1259 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1260 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
1261 if (TREE_CODE (field) == FIELD_DECL)
1264 for (binfo = TYPE_BINFO (t), i = 0;
1265 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1267 tree basetype = TREE_TYPE (base_binfo);
1269 gcc_assert (COMPLETE_TYPE_P (basetype));
1271 /* If any base class is non-literal, so is the derived class. */
1272 if (!CLASSTYPE_LITERAL_P (basetype))
1273 CLASSTYPE_LITERAL_P (t) = false;
1275 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1276 here because the case of virtual functions but non-virtual
1277 dtor is handled in finish_struct_1. */
1278 if (!TYPE_POLYMORPHIC_P (basetype))
1279 warning (OPT_Weffc__,
1280 "base class %q#T has a non-virtual destructor", basetype);
1282 /* If the base class doesn't have copy constructors or
1283 assignment operators that take const references, then the
1284 derived class cannot have such a member automatically
1286 if (TYPE_HAS_COPY_CTOR (basetype)
1287 && ! TYPE_HAS_CONST_COPY_CTOR (basetype))
1288 *cant_have_const_ctor_p = 1;
1289 if (TYPE_HAS_COPY_ASSIGN (basetype)
1290 && !TYPE_HAS_CONST_COPY_ASSIGN (basetype))
1291 *no_const_asn_ref_p = 1;
1293 if (BINFO_VIRTUAL_P (base_binfo))
1294 /* A virtual base does not effect nearly emptiness. */
1296 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1298 if (seen_non_virtual_nearly_empty_base_p)
1299 /* And if there is more than one nearly empty base, then the
1300 derived class is not nearly empty either. */
1301 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1303 /* Remember we've seen one. */
1304 seen_non_virtual_nearly_empty_base_p = 1;
1306 else if (!is_empty_class (basetype))
1307 /* If the base class is not empty or nearly empty, then this
1308 class cannot be nearly empty. */
1309 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1311 /* A lot of properties from the bases also apply to the derived
1313 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1314 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1315 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1316 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
1317 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (basetype)
1318 || !TYPE_HAS_COPY_ASSIGN (basetype));
1319 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (basetype)
1320 || !TYPE_HAS_COPY_CTOR (basetype));
1321 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t)
1322 |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (basetype);
1323 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (basetype);
1324 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1325 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1326 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1327 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
1328 || TYPE_HAS_COMPLEX_DFLT (basetype));
1330 /* A standard-layout class is a class that:
1332 * has no non-standard-layout base classes, */
1333 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1334 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1337 /* ...has no base classes of the same type as the first non-static
1339 if (field && DECL_CONTEXT (field) == t
1340 && (same_type_ignoring_top_level_qualifiers_p
1341 (TREE_TYPE (field), basetype)))
1342 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1344 /* ...either has no non-static data members in the most-derived
1345 class and at most one base class with non-static data
1346 members, or has no base classes with non-static data
1348 for (basefield = TYPE_FIELDS (basetype); basefield;
1349 basefield = DECL_CHAIN (basefield))
1350 if (TREE_CODE (basefield) == FIELD_DECL)
1353 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1362 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1363 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1364 that have had a nearly-empty virtual primary base stolen by some
1365 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1369 determine_primary_bases (tree t)
1372 tree primary = NULL_TREE;
1373 tree type_binfo = TYPE_BINFO (t);
1376 /* Determine the primary bases of our bases. */
1377 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1378 base_binfo = TREE_CHAIN (base_binfo))
1380 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1382 /* See if we're the non-virtual primary of our inheritance
1384 if (!BINFO_VIRTUAL_P (base_binfo))
1386 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1387 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1390 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1391 BINFO_TYPE (parent_primary)))
1392 /* We are the primary binfo. */
1393 BINFO_PRIMARY_P (base_binfo) = 1;
1395 /* Determine if we have a virtual primary base, and mark it so.
1397 if (primary && BINFO_VIRTUAL_P (primary))
1399 tree this_primary = copied_binfo (primary, base_binfo);
1401 if (BINFO_PRIMARY_P (this_primary))
1402 /* Someone already claimed this base. */
1403 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1408 BINFO_PRIMARY_P (this_primary) = 1;
1409 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1411 /* A virtual binfo might have been copied from within
1412 another hierarchy. As we're about to use it as a
1413 primary base, make sure the offsets match. */
1414 delta = size_diffop_loc (input_location,
1416 BINFO_OFFSET (base_binfo)),
1418 BINFO_OFFSET (this_primary)));
1420 propagate_binfo_offsets (this_primary, delta);
1425 /* First look for a dynamic direct non-virtual base. */
1426 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1428 tree basetype = BINFO_TYPE (base_binfo);
1430 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1432 primary = base_binfo;
1437 /* A "nearly-empty" virtual base class can be the primary base
1438 class, if no non-virtual polymorphic base can be found. Look for
1439 a nearly-empty virtual dynamic base that is not already a primary
1440 base of something in the hierarchy. If there is no such base,
1441 just pick the first nearly-empty virtual base. */
1443 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1444 base_binfo = TREE_CHAIN (base_binfo))
1445 if (BINFO_VIRTUAL_P (base_binfo)
1446 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1448 if (!BINFO_PRIMARY_P (base_binfo))
1450 /* Found one that is not primary. */
1451 primary = base_binfo;
1455 /* Remember the first candidate. */
1456 primary = base_binfo;
1460 /* If we've got a primary base, use it. */
1463 tree basetype = BINFO_TYPE (primary);
1465 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1466 if (BINFO_PRIMARY_P (primary))
1467 /* We are stealing a primary base. */
1468 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1469 BINFO_PRIMARY_P (primary) = 1;
1470 if (BINFO_VIRTUAL_P (primary))
1474 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1475 /* A virtual binfo might have been copied from within
1476 another hierarchy. As we're about to use it as a primary
1477 base, make sure the offsets match. */
1478 delta = size_diffop_loc (input_location, ssize_int (0),
1479 convert (ssizetype, BINFO_OFFSET (primary)));
1481 propagate_binfo_offsets (primary, delta);
1484 primary = TYPE_BINFO (basetype);
1486 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1487 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1488 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1492 /* Update the variant types of T. */
1495 fixup_type_variants (tree t)
1502 for (variants = TYPE_NEXT_VARIANT (t);
1504 variants = TYPE_NEXT_VARIANT (variants))
1506 /* These fields are in the _TYPE part of the node, not in
1507 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1508 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1509 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1510 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1511 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1513 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1515 TYPE_BINFO (variants) = TYPE_BINFO (t);
1517 /* Copy whatever these are holding today. */
1518 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1519 TYPE_METHODS (variants) = TYPE_METHODS (t);
1520 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1524 /* Early variant fixups: we apply attributes at the beginning of the class
1525 definition, and we need to fix up any variants that have already been
1526 made via elaborated-type-specifier so that check_qualified_type works. */
1529 fixup_attribute_variants (tree t)
1536 for (variants = TYPE_NEXT_VARIANT (t);
1538 variants = TYPE_NEXT_VARIANT (variants))
1540 /* These are the two fields that check_qualified_type looks at and
1541 are affected by attributes. */
1542 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1543 TYPE_ALIGN (variants) = TYPE_ALIGN (t);
1547 /* Set memoizing fields and bits of T (and its variants) for later
1551 finish_struct_bits (tree t)
1553 /* Fix up variants (if any). */
1554 fixup_type_variants (t);
1556 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1557 /* For a class w/o baseclasses, 'finish_struct' has set
1558 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1559 Similarly for a class whose base classes do not have vtables.
1560 When neither of these is true, we might have removed abstract
1561 virtuals (by providing a definition), added some (by declaring
1562 new ones), or redeclared ones from a base class. We need to
1563 recalculate what's really an abstract virtual at this point (by
1564 looking in the vtables). */
1565 get_pure_virtuals (t);
1567 /* If this type has a copy constructor or a destructor, force its
1568 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1569 nonzero. This will cause it to be passed by invisible reference
1570 and prevent it from being returned in a register. */
1571 if (type_has_nontrivial_copy_init (t)
1572 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1575 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1576 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1578 SET_TYPE_MODE (variants, BLKmode);
1579 TREE_ADDRESSABLE (variants) = 1;
1584 /* Issue warnings about T having private constructors, but no friends,
1587 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1588 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1589 non-private static member functions. */
1592 maybe_warn_about_overly_private_class (tree t)
1594 int has_member_fn = 0;
1595 int has_nonprivate_method = 0;
1598 if (!warn_ctor_dtor_privacy
1599 /* If the class has friends, those entities might create and
1600 access instances, so we should not warn. */
1601 || (CLASSTYPE_FRIEND_CLASSES (t)
1602 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1603 /* We will have warned when the template was declared; there's
1604 no need to warn on every instantiation. */
1605 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1606 /* There's no reason to even consider warning about this
1610 /* We only issue one warning, if more than one applies, because
1611 otherwise, on code like:
1614 // Oops - forgot `public:'
1620 we warn several times about essentially the same problem. */
1622 /* Check to see if all (non-constructor, non-destructor) member
1623 functions are private. (Since there are no friends or
1624 non-private statics, we can't ever call any of the private member
1626 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
1627 /* We're not interested in compiler-generated methods; they don't
1628 provide any way to call private members. */
1629 if (!DECL_ARTIFICIAL (fn))
1631 if (!TREE_PRIVATE (fn))
1633 if (DECL_STATIC_FUNCTION_P (fn))
1634 /* A non-private static member function is just like a
1635 friend; it can create and invoke private member
1636 functions, and be accessed without a class
1640 has_nonprivate_method = 1;
1641 /* Keep searching for a static member function. */
1643 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1647 if (!has_nonprivate_method && has_member_fn)
1649 /* There are no non-private methods, and there's at least one
1650 private member function that isn't a constructor or
1651 destructor. (If all the private members are
1652 constructors/destructors we want to use the code below that
1653 issues error messages specifically referring to
1654 constructors/destructors.) */
1656 tree binfo = TYPE_BINFO (t);
1658 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1659 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1661 has_nonprivate_method = 1;
1664 if (!has_nonprivate_method)
1666 warning (OPT_Wctor_dtor_privacy,
1667 "all member functions in class %qT are private", t);
1672 /* Even if some of the member functions are non-private, the class
1673 won't be useful for much if all the constructors or destructors
1674 are private: such an object can never be created or destroyed. */
1675 fn = CLASSTYPE_DESTRUCTORS (t);
1676 if (fn && TREE_PRIVATE (fn))
1678 warning (OPT_Wctor_dtor_privacy,
1679 "%q#T only defines a private destructor and has no friends",
1684 /* Warn about classes that have private constructors and no friends. */
1685 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1686 /* Implicitly generated constructors are always public. */
1687 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1688 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1690 int nonprivate_ctor = 0;
1692 /* If a non-template class does not define a copy
1693 constructor, one is defined for it, enabling it to avoid
1694 this warning. For a template class, this does not
1695 happen, and so we would normally get a warning on:
1697 template <class T> class C { private: C(); };
1699 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1700 complete non-template or fully instantiated classes have this
1702 if (!TYPE_HAS_COPY_CTOR (t))
1703 nonprivate_ctor = 1;
1705 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1707 tree ctor = OVL_CURRENT (fn);
1708 /* Ideally, we wouldn't count copy constructors (or, in
1709 fact, any constructor that takes an argument of the
1710 class type as a parameter) because such things cannot
1711 be used to construct an instance of the class unless
1712 you already have one. But, for now at least, we're
1714 if (! TREE_PRIVATE (ctor))
1716 nonprivate_ctor = 1;
1721 if (nonprivate_ctor == 0)
1723 warning (OPT_Wctor_dtor_privacy,
1724 "%q#T only defines private constructors and has no friends",
1732 gt_pointer_operator new_value;
1736 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1739 method_name_cmp (const void* m1_p, const void* m2_p)
1741 const tree *const m1 = (const tree *) m1_p;
1742 const tree *const m2 = (const tree *) m2_p;
1744 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1746 if (*m1 == NULL_TREE)
1748 if (*m2 == NULL_TREE)
1750 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1755 /* This routine compares two fields like method_name_cmp but using the
1756 pointer operator in resort_field_decl_data. */
1759 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1761 const tree *const m1 = (const tree *) m1_p;
1762 const tree *const m2 = (const tree *) m2_p;
1763 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1765 if (*m1 == NULL_TREE)
1767 if (*m2 == NULL_TREE)
1770 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1771 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1772 resort_data.new_value (&d1, resort_data.cookie);
1773 resort_data.new_value (&d2, resort_data.cookie);
1780 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1783 resort_type_method_vec (void* obj,
1784 void* orig_obj ATTRIBUTE_UNUSED ,
1785 gt_pointer_operator new_value,
1788 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1789 int len = VEC_length (tree, method_vec);
1793 /* The type conversion ops have to live at the front of the vec, so we
1795 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1796 VEC_iterate (tree, method_vec, slot, fn);
1798 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1803 resort_data.new_value = new_value;
1804 resort_data.cookie = cookie;
1805 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1806 resort_method_name_cmp);
1810 /* Warn about duplicate methods in fn_fields.
1812 Sort methods that are not special (i.e., constructors, destructors,
1813 and type conversion operators) so that we can find them faster in
1817 finish_struct_methods (tree t)
1820 VEC(tree,gc) *method_vec;
1823 method_vec = CLASSTYPE_METHOD_VEC (t);
1827 len = VEC_length (tree, method_vec);
1829 /* Clear DECL_IN_AGGR_P for all functions. */
1830 for (fn_fields = TYPE_METHODS (t); fn_fields;
1831 fn_fields = DECL_CHAIN (fn_fields))
1832 DECL_IN_AGGR_P (fn_fields) = 0;
1834 /* Issue warnings about private constructors and such. If there are
1835 no methods, then some public defaults are generated. */
1836 maybe_warn_about_overly_private_class (t);
1838 /* The type conversion ops have to live at the front of the vec, so we
1840 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1841 VEC_iterate (tree, method_vec, slot, fn_fields);
1843 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1846 qsort (VEC_address (tree, method_vec) + slot,
1847 len-slot, sizeof (tree), method_name_cmp);
1850 /* Make BINFO's vtable have N entries, including RTTI entries,
1851 vbase and vcall offsets, etc. Set its type and call the back end
1855 layout_vtable_decl (tree binfo, int n)
1860 atype = build_array_of_n_type (vtable_entry_type, n);
1861 layout_type (atype);
1863 /* We may have to grow the vtable. */
1864 vtable = get_vtbl_decl_for_binfo (binfo);
1865 if (!same_type_p (TREE_TYPE (vtable), atype))
1867 TREE_TYPE (vtable) = atype;
1868 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1869 layout_decl (vtable, 0);
1873 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1874 have the same signature. */
1877 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1879 /* One destructor overrides another if they are the same kind of
1881 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1882 && special_function_p (base_fndecl) == special_function_p (fndecl))
1884 /* But a non-destructor never overrides a destructor, nor vice
1885 versa, nor do different kinds of destructors override
1886 one-another. For example, a complete object destructor does not
1887 override a deleting destructor. */
1888 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1891 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1892 || (DECL_CONV_FN_P (fndecl)
1893 && DECL_CONV_FN_P (base_fndecl)
1894 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1895 DECL_CONV_FN_TYPE (base_fndecl))))
1897 tree types, base_types;
1898 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1899 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1900 if ((cp_type_quals (TREE_TYPE (TREE_VALUE (base_types)))
1901 == cp_type_quals (TREE_TYPE (TREE_VALUE (types))))
1902 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1908 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1912 base_derived_from (tree derived, tree base)
1916 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1918 if (probe == derived)
1920 else if (BINFO_VIRTUAL_P (probe))
1921 /* If we meet a virtual base, we can't follow the inheritance
1922 any more. See if the complete type of DERIVED contains
1923 such a virtual base. */
1924 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1930 typedef struct find_final_overrider_data_s {
1931 /* The function for which we are trying to find a final overrider. */
1933 /* The base class in which the function was declared. */
1934 tree declaring_base;
1935 /* The candidate overriders. */
1937 /* Path to most derived. */
1938 VEC(tree,heap) *path;
1939 } find_final_overrider_data;
1941 /* Add the overrider along the current path to FFOD->CANDIDATES.
1942 Returns true if an overrider was found; false otherwise. */
1945 dfs_find_final_overrider_1 (tree binfo,
1946 find_final_overrider_data *ffod,
1951 /* If BINFO is not the most derived type, try a more derived class.
1952 A definition there will overrider a definition here. */
1956 if (dfs_find_final_overrider_1
1957 (VEC_index (tree, ffod->path, depth), ffod, depth))
1961 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1964 tree *candidate = &ffod->candidates;
1966 /* Remove any candidates overridden by this new function. */
1969 /* If *CANDIDATE overrides METHOD, then METHOD
1970 cannot override anything else on the list. */
1971 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1973 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1974 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1975 *candidate = TREE_CHAIN (*candidate);
1977 candidate = &TREE_CHAIN (*candidate);
1980 /* Add the new function. */
1981 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1988 /* Called from find_final_overrider via dfs_walk. */
1991 dfs_find_final_overrider_pre (tree binfo, void *data)
1993 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1995 if (binfo == ffod->declaring_base)
1996 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1997 VEC_safe_push (tree, heap, ffod->path, binfo);
2003 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
2005 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
2006 VEC_pop (tree, ffod->path);
2011 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
2012 FN and whose TREE_VALUE is the binfo for the base where the
2013 overriding occurs. BINFO (in the hierarchy dominated by the binfo
2014 DERIVED) is the base object in which FN is declared. */
2017 find_final_overrider (tree derived, tree binfo, tree fn)
2019 find_final_overrider_data ffod;
2021 /* Getting this right is a little tricky. This is valid:
2023 struct S { virtual void f (); };
2024 struct T { virtual void f (); };
2025 struct U : public S, public T { };
2027 even though calling `f' in `U' is ambiguous. But,
2029 struct R { virtual void f(); };
2030 struct S : virtual public R { virtual void f (); };
2031 struct T : virtual public R { virtual void f (); };
2032 struct U : public S, public T { };
2034 is not -- there's no way to decide whether to put `S::f' or
2035 `T::f' in the vtable for `R'.
2037 The solution is to look at all paths to BINFO. If we find
2038 different overriders along any two, then there is a problem. */
2039 if (DECL_THUNK_P (fn))
2040 fn = THUNK_TARGET (fn);
2042 /* Determine the depth of the hierarchy. */
2044 ffod.declaring_base = binfo;
2045 ffod.candidates = NULL_TREE;
2046 ffod.path = VEC_alloc (tree, heap, 30);
2048 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2049 dfs_find_final_overrider_post, &ffod);
2051 VEC_free (tree, heap, ffod.path);
2053 /* If there was no winner, issue an error message. */
2054 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2055 return error_mark_node;
2057 return ffod.candidates;
2060 /* Return the index of the vcall offset for FN when TYPE is used as a
2064 get_vcall_index (tree fn, tree type)
2066 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2070 FOR_EACH_VEC_ELT (tree_pair_s, indices, ix, p)
2071 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2072 || same_signature_p (fn, p->purpose))
2075 /* There should always be an appropriate index. */
2079 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2080 dominated by T. FN is the old function; VIRTUALS points to the
2081 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2082 of that entry in the list. */
2085 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2093 tree overrider_fn, overrider_target;
2094 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2095 tree over_return, base_return;
2098 /* Find the nearest primary base (possibly binfo itself) which defines
2099 this function; this is the class the caller will convert to when
2100 calling FN through BINFO. */
2101 for (b = binfo; ; b = get_primary_binfo (b))
2104 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2107 /* The nearest definition is from a lost primary. */
2108 if (BINFO_LOST_PRIMARY_P (b))
2113 /* Find the final overrider. */
2114 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2115 if (overrider == error_mark_node)
2117 error ("no unique final overrider for %qD in %qT", target_fn, t);
2120 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2122 /* Check for adjusting covariant return types. */
2123 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2124 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2126 if (POINTER_TYPE_P (over_return)
2127 && TREE_CODE (over_return) == TREE_CODE (base_return)
2128 && CLASS_TYPE_P (TREE_TYPE (over_return))
2129 && CLASS_TYPE_P (TREE_TYPE (base_return))
2130 /* If the overrider is invalid, don't even try. */
2131 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2133 /* If FN is a covariant thunk, we must figure out the adjustment
2134 to the final base FN was converting to. As OVERRIDER_TARGET might
2135 also be converting to the return type of FN, we have to
2136 combine the two conversions here. */
2137 tree fixed_offset, virtual_offset;
2139 over_return = TREE_TYPE (over_return);
2140 base_return = TREE_TYPE (base_return);
2142 if (DECL_THUNK_P (fn))
2144 gcc_assert (DECL_RESULT_THUNK_P (fn));
2145 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2146 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2149 fixed_offset = virtual_offset = NULL_TREE;
2152 /* Find the equivalent binfo within the return type of the
2153 overriding function. We will want the vbase offset from
2155 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2157 else if (!same_type_ignoring_top_level_qualifiers_p
2158 (over_return, base_return))
2160 /* There was no existing virtual thunk (which takes
2161 precedence). So find the binfo of the base function's
2162 return type within the overriding function's return type.
2163 We cannot call lookup base here, because we're inside a
2164 dfs_walk, and will therefore clobber the BINFO_MARKED
2165 flags. Fortunately we know the covariancy is valid (it
2166 has already been checked), so we can just iterate along
2167 the binfos, which have been chained in inheritance graph
2168 order. Of course it is lame that we have to repeat the
2169 search here anyway -- we should really be caching pieces
2170 of the vtable and avoiding this repeated work. */
2171 tree thunk_binfo, base_binfo;
2173 /* Find the base binfo within the overriding function's
2174 return type. We will always find a thunk_binfo, except
2175 when the covariancy is invalid (which we will have
2176 already diagnosed). */
2177 for (base_binfo = TYPE_BINFO (base_return),
2178 thunk_binfo = TYPE_BINFO (over_return);
2180 thunk_binfo = TREE_CHAIN (thunk_binfo))
2181 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2182 BINFO_TYPE (base_binfo)))
2185 /* See if virtual inheritance is involved. */
2186 for (virtual_offset = thunk_binfo;
2188 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2189 if (BINFO_VIRTUAL_P (virtual_offset))
2193 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2195 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2199 /* We convert via virtual base. Adjust the fixed
2200 offset to be from there. */
2202 size_diffop (offset,
2204 BINFO_OFFSET (virtual_offset)));
2207 /* There was an existing fixed offset, this must be
2208 from the base just converted to, and the base the
2209 FN was thunking to. */
2210 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2212 fixed_offset = offset;
2216 if (fixed_offset || virtual_offset)
2217 /* Replace the overriding function with a covariant thunk. We
2218 will emit the overriding function in its own slot as
2220 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2221 fixed_offset, virtual_offset);
2224 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2225 !DECL_THUNK_P (fn));
2227 /* If we need a covariant thunk, then we may need to adjust first_defn.
2228 The ABI specifies that the thunks emitted with a function are
2229 determined by which bases the function overrides, so we need to be
2230 sure that we're using a thunk for some overridden base; even if we
2231 know that the necessary this adjustment is zero, there may not be an
2232 appropriate zero-this-adjusment thunk for us to use since thunks for
2233 overriding virtual bases always use the vcall offset.
2235 Furthermore, just choosing any base that overrides this function isn't
2236 quite right, as this slot won't be used for calls through a type that
2237 puts a covariant thunk here. Calling the function through such a type
2238 will use a different slot, and that slot is the one that determines
2239 the thunk emitted for that base.
2241 So, keep looking until we find the base that we're really overriding
2242 in this slot: the nearest primary base that doesn't use a covariant
2243 thunk in this slot. */
2244 if (overrider_target != overrider_fn)
2246 if (BINFO_TYPE (b) == DECL_CONTEXT (overrider_target))
2247 /* We already know that the overrider needs a covariant thunk. */
2248 b = get_primary_binfo (b);
2249 for (; ; b = get_primary_binfo (b))
2251 tree main_binfo = TYPE_BINFO (BINFO_TYPE (b));
2252 tree bv = chain_index (ix, BINFO_VIRTUALS (main_binfo));
2253 if (BINFO_LOST_PRIMARY_P (b))
2255 if (!DECL_THUNK_P (TREE_VALUE (bv)))
2261 /* Assume that we will produce a thunk that convert all the way to
2262 the final overrider, and not to an intermediate virtual base. */
2263 virtual_base = NULL_TREE;
2265 /* See if we can convert to an intermediate virtual base first, and then
2266 use the vcall offset located there to finish the conversion. */
2267 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2269 /* If we find the final overrider, then we can stop
2271 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2272 BINFO_TYPE (TREE_VALUE (overrider))))
2275 /* If we find a virtual base, and we haven't yet found the
2276 overrider, then there is a virtual base between the
2277 declaring base (first_defn) and the final overrider. */
2278 if (BINFO_VIRTUAL_P (b))
2285 /* Compute the constant adjustment to the `this' pointer. The
2286 `this' pointer, when this function is called, will point at BINFO
2287 (or one of its primary bases, which are at the same offset). */
2289 /* The `this' pointer needs to be adjusted from the declaration to
2290 the nearest virtual base. */
2291 delta = size_diffop_loc (input_location,
2292 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2293 convert (ssizetype, BINFO_OFFSET (first_defn)));
2295 /* If the nearest definition is in a lost primary, we don't need an
2296 entry in our vtable. Except possibly in a constructor vtable,
2297 if we happen to get our primary back. In that case, the offset
2298 will be zero, as it will be a primary base. */
2299 delta = size_zero_node;
2301 /* The `this' pointer needs to be adjusted from pointing to
2302 BINFO to pointing at the base where the final overrider
2304 delta = size_diffop_loc (input_location,
2306 BINFO_OFFSET (TREE_VALUE (overrider))),
2307 convert (ssizetype, BINFO_OFFSET (binfo)));
2309 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2312 BV_VCALL_INDEX (*virtuals)
2313 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2315 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2318 BV_LOST_PRIMARY (*virtuals) = true;
2321 /* Called from modify_all_vtables via dfs_walk. */
2324 dfs_modify_vtables (tree binfo, void* data)
2326 tree t = (tree) data;
2331 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2332 /* A base without a vtable needs no modification, and its bases
2333 are uninteresting. */
2334 return dfs_skip_bases;
2336 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2337 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2338 /* Don't do the primary vtable, if it's new. */
2341 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2342 /* There's no need to modify the vtable for a non-virtual primary
2343 base; we're not going to use that vtable anyhow. We do still
2344 need to do this for virtual primary bases, as they could become
2345 non-primary in a construction vtable. */
2348 make_new_vtable (t, binfo);
2350 /* Now, go through each of the virtual functions in the virtual
2351 function table for BINFO. Find the final overrider, and update
2352 the BINFO_VIRTUALS list appropriately. */
2353 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2354 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2356 ix++, virtuals = TREE_CHAIN (virtuals),
2357 old_virtuals = TREE_CHAIN (old_virtuals))
2358 update_vtable_entry_for_fn (t,
2360 BV_FN (old_virtuals),
2366 /* Update all of the primary and secondary vtables for T. Create new
2367 vtables as required, and initialize their RTTI information. Each
2368 of the functions in VIRTUALS is declared in T and may override a
2369 virtual function from a base class; find and modify the appropriate
2370 entries to point to the overriding functions. Returns a list, in
2371 declaration order, of the virtual functions that are declared in T,
2372 but do not appear in the primary base class vtable, and which
2373 should therefore be appended to the end of the vtable for T. */
2376 modify_all_vtables (tree t, tree virtuals)
2378 tree binfo = TYPE_BINFO (t);
2381 /* Update all of the vtables. */
2382 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2384 /* Add virtual functions not already in our primary vtable. These
2385 will be both those introduced by this class, and those overridden
2386 from secondary bases. It does not include virtuals merely
2387 inherited from secondary bases. */
2388 for (fnsp = &virtuals; *fnsp; )
2390 tree fn = TREE_VALUE (*fnsp);
2392 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2393 || DECL_VINDEX (fn) == error_mark_node)
2395 /* We don't need to adjust the `this' pointer when
2396 calling this function. */
2397 BV_DELTA (*fnsp) = integer_zero_node;
2398 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2400 /* This is a function not already in our vtable. Keep it. */
2401 fnsp = &TREE_CHAIN (*fnsp);
2404 /* We've already got an entry for this function. Skip it. */
2405 *fnsp = TREE_CHAIN (*fnsp);
2411 /* Get the base virtual function declarations in T that have the
2415 get_basefndecls (tree name, tree t)
2418 tree base_fndecls = NULL_TREE;
2419 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2422 /* Find virtual functions in T with the indicated NAME. */
2423 i = lookup_fnfields_1 (t, name);
2425 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2427 methods = OVL_NEXT (methods))
2429 tree method = OVL_CURRENT (methods);
2431 if (TREE_CODE (method) == FUNCTION_DECL
2432 && DECL_VINDEX (method))
2433 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2437 return base_fndecls;
2439 for (i = 0; i < n_baseclasses; i++)
2441 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2442 base_fndecls = chainon (get_basefndecls (name, basetype),
2446 return base_fndecls;
2449 /* If this declaration supersedes the declaration of
2450 a method declared virtual in the base class, then
2451 mark this field as being virtual as well. */
2454 check_for_override (tree decl, tree ctype)
2456 if (TREE_CODE (decl) == TEMPLATE_DECL)
2457 /* In [temp.mem] we have:
2459 A specialization of a member function template does not
2460 override a virtual function from a base class. */
2462 if ((DECL_DESTRUCTOR_P (decl)
2463 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2464 || DECL_CONV_FN_P (decl))
2465 && look_for_overrides (ctype, decl)
2466 && !DECL_STATIC_FUNCTION_P (decl))
2467 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2468 the error_mark_node so that we know it is an overriding
2470 DECL_VINDEX (decl) = decl;
2472 if (DECL_VIRTUAL_P (decl))
2474 if (!DECL_VINDEX (decl))
2475 DECL_VINDEX (decl) = error_mark_node;
2476 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2480 /* Warn about hidden virtual functions that are not overridden in t.
2481 We know that constructors and destructors don't apply. */
2484 warn_hidden (tree t)
2486 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2490 /* We go through each separately named virtual function. */
2491 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2492 VEC_iterate (tree, method_vec, i, fns);
2503 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2504 have the same name. Figure out what name that is. */
2505 name = DECL_NAME (OVL_CURRENT (fns));
2506 /* There are no possibly hidden functions yet. */
2507 base_fndecls = NULL_TREE;
2508 /* Iterate through all of the base classes looking for possibly
2509 hidden functions. */
2510 for (binfo = TYPE_BINFO (t), j = 0;
2511 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2513 tree basetype = BINFO_TYPE (base_binfo);
2514 base_fndecls = chainon (get_basefndecls (name, basetype),
2518 /* If there are no functions to hide, continue. */
2522 /* Remove any overridden functions. */
2523 for (fn = fns; fn; fn = OVL_NEXT (fn))
2525 fndecl = OVL_CURRENT (fn);
2526 if (DECL_VINDEX (fndecl))
2528 tree *prev = &base_fndecls;
2531 /* If the method from the base class has the same
2532 signature as the method from the derived class, it
2533 has been overridden. */
2534 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2535 *prev = TREE_CHAIN (*prev);
2537 prev = &TREE_CHAIN (*prev);
2541 /* Now give a warning for all base functions without overriders,
2542 as they are hidden. */
2543 while (base_fndecls)
2545 /* Here we know it is a hider, and no overrider exists. */
2546 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2547 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2548 base_fndecls = TREE_CHAIN (base_fndecls);
2553 /* Check for things that are invalid. There are probably plenty of other
2554 things we should check for also. */
2557 finish_struct_anon (tree t)
2561 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
2563 if (TREE_STATIC (field))
2565 if (TREE_CODE (field) != FIELD_DECL)
2568 if (DECL_NAME (field) == NULL_TREE
2569 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2571 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2572 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2573 for (; elt; elt = DECL_CHAIN (elt))
2575 /* We're generally only interested in entities the user
2576 declared, but we also find nested classes by noticing
2577 the TYPE_DECL that we create implicitly. You're
2578 allowed to put one anonymous union inside another,
2579 though, so we explicitly tolerate that. We use
2580 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2581 we also allow unnamed types used for defining fields. */
2582 if (DECL_ARTIFICIAL (elt)
2583 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2584 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2587 if (TREE_CODE (elt) != FIELD_DECL)
2590 permerror (input_location, "%q+#D invalid; an anonymous union can "
2591 "only have non-static data members", elt);
2593 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2594 "only have non-static data members", elt);
2598 if (TREE_PRIVATE (elt))
2601 permerror (input_location, "private member %q+#D in anonymous union", elt);
2603 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2605 else if (TREE_PROTECTED (elt))
2608 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2610 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2613 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2614 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2620 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2621 will be used later during class template instantiation.
2622 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2623 a non-static member data (FIELD_DECL), a member function
2624 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2625 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2626 When FRIEND_P is nonzero, T is either a friend class
2627 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2628 (FUNCTION_DECL, TEMPLATE_DECL). */
2631 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2633 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2634 if (CLASSTYPE_TEMPLATE_INFO (type))
2635 CLASSTYPE_DECL_LIST (type)
2636 = tree_cons (friend_p ? NULL_TREE : type,
2637 t, CLASSTYPE_DECL_LIST (type));
2640 /* Create default constructors, assignment operators, and so forth for
2641 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2642 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2643 the class cannot have a default constructor, copy constructor
2644 taking a const reference argument, or an assignment operator taking
2645 a const reference, respectively. */
2648 add_implicitly_declared_members (tree t,
2649 int cant_have_const_cctor,
2650 int cant_have_const_assignment)
2653 if (!CLASSTYPE_DESTRUCTORS (t))
2655 /* In general, we create destructors lazily. */
2656 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2658 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2659 && TYPE_FOR_JAVA (t))
2660 /* But if this is a Java class, any non-trivial destructor is
2661 invalid, even if compiler-generated. Therefore, if the
2662 destructor is non-trivial we create it now. */
2663 lazily_declare_fn (sfk_destructor, t);
2668 If there is no user-declared constructor for a class, a default
2669 constructor is implicitly declared. */
2670 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2672 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2673 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2674 if (cxx_dialect >= cxx0x)
2675 TYPE_HAS_CONSTEXPR_CTOR (t)
2676 = synthesized_default_constructor_is_constexpr (t);
2681 If a class definition does not explicitly declare a copy
2682 constructor, one is declared implicitly. */
2683 if (! TYPE_HAS_COPY_CTOR (t) && ! TYPE_FOR_JAVA (t)
2684 && !type_has_move_constructor (t))
2686 TYPE_HAS_COPY_CTOR (t) = 1;
2687 TYPE_HAS_CONST_COPY_CTOR (t) = !cant_have_const_cctor;
2688 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2689 if (cxx_dialect >= cxx0x)
2690 CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
2693 /* If there is no assignment operator, one will be created if and
2694 when it is needed. For now, just record whether or not the type
2695 of the parameter to the assignment operator will be a const or
2696 non-const reference. */
2697 if (!TYPE_HAS_COPY_ASSIGN (t) && !TYPE_FOR_JAVA (t)
2698 && !type_has_move_assign (t))
2700 TYPE_HAS_COPY_ASSIGN (t) = 1;
2701 TYPE_HAS_CONST_COPY_ASSIGN (t) = !cant_have_const_assignment;
2702 CLASSTYPE_LAZY_COPY_ASSIGN (t) = 1;
2703 if (cxx_dialect >= cxx0x)
2704 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 1;
2707 /* We can't be lazy about declaring functions that might override
2708 a virtual function from a base class. */
2709 if (TYPE_POLYMORPHIC_P (t)
2710 && (CLASSTYPE_LAZY_COPY_ASSIGN (t)
2711 || CLASSTYPE_LAZY_MOVE_ASSIGN (t)
2712 || CLASSTYPE_LAZY_DESTRUCTOR (t)))
2714 tree binfo = TYPE_BINFO (t);
2717 tree opname = ansi_assopname (NOP_EXPR);
2718 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ++ix)
2721 for (bv = BINFO_VIRTUALS (base_binfo); bv; bv = TREE_CHAIN (bv))
2723 tree fn = BV_FN (bv);
2724 if (DECL_NAME (fn) == opname)
2726 if (CLASSTYPE_LAZY_COPY_ASSIGN (t))
2727 lazily_declare_fn (sfk_copy_assignment, t);
2728 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
2729 lazily_declare_fn (sfk_move_assignment, t);
2731 else if (DECL_DESTRUCTOR_P (fn)
2732 && CLASSTYPE_LAZY_DESTRUCTOR (t))
2733 lazily_declare_fn (sfk_destructor, t);
2739 /* Subroutine of finish_struct_1. Recursively count the number of fields
2740 in TYPE, including anonymous union members. */
2743 count_fields (tree fields)
2747 for (x = fields; x; x = DECL_CHAIN (x))
2749 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2750 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2757 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2758 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2761 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2764 for (x = fields; x; x = DECL_CHAIN (x))
2766 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2767 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2769 field_vec->elts[idx++] = x;
2774 /* FIELD is a bit-field. We are finishing the processing for its
2775 enclosing type. Issue any appropriate messages and set appropriate
2776 flags. Returns false if an error has been diagnosed. */
2779 check_bitfield_decl (tree field)
2781 tree type = TREE_TYPE (field);
2784 /* Extract the declared width of the bitfield, which has been
2785 temporarily stashed in DECL_INITIAL. */
2786 w = DECL_INITIAL (field);
2787 gcc_assert (w != NULL_TREE);
2788 /* Remove the bit-field width indicator so that the rest of the
2789 compiler does not treat that value as an initializer. */
2790 DECL_INITIAL (field) = NULL_TREE;
2792 /* Detect invalid bit-field type. */
2793 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2795 error ("bit-field %q+#D with non-integral type", field);
2796 w = error_mark_node;
2800 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2803 /* detect invalid field size. */
2804 w = cxx_constant_value (w);
2806 if (TREE_CODE (w) != INTEGER_CST)
2808 error ("bit-field %q+D width not an integer constant", field);
2809 w = error_mark_node;
2811 else if (tree_int_cst_sgn (w) < 0)
2813 error ("negative width in bit-field %q+D", field);
2814 w = error_mark_node;
2816 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2818 error ("zero width for bit-field %q+D", field);
2819 w = error_mark_node;
2821 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2822 && TREE_CODE (type) != ENUMERAL_TYPE
2823 && TREE_CODE (type) != BOOLEAN_TYPE)
2824 warning (0, "width of %q+D exceeds its type", field);
2825 else if (TREE_CODE (type) == ENUMERAL_TYPE
2826 && (0 > (compare_tree_int
2827 (w, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type))))))
2828 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2831 if (w != error_mark_node)
2833 DECL_SIZE (field) = convert (bitsizetype, w);
2834 DECL_BIT_FIELD (field) = 1;
2839 /* Non-bit-fields are aligned for their type. */
2840 DECL_BIT_FIELD (field) = 0;
2841 CLEAR_DECL_C_BIT_FIELD (field);
2846 /* FIELD is a non bit-field. We are finishing the processing for its
2847 enclosing type T. Issue any appropriate messages and set appropriate
2851 check_field_decl (tree field,
2853 int* cant_have_const_ctor,
2854 int* no_const_asn_ref,
2855 int* any_default_members)
2857 tree type = strip_array_types (TREE_TYPE (field));
2859 /* In C++98 an anonymous union cannot contain any fields which would change
2860 the settings of CANT_HAVE_CONST_CTOR and friends. */
2861 if (ANON_UNION_TYPE_P (type) && cxx_dialect < cxx0x)
2863 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2864 structs. So, we recurse through their fields here. */
2865 else if (ANON_AGGR_TYPE_P (type))
2869 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2870 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2871 check_field_decl (fields, t, cant_have_const_ctor,
2872 no_const_asn_ref, any_default_members);
2874 /* Check members with class type for constructors, destructors,
2876 else if (CLASS_TYPE_P (type))
2878 /* Never let anything with uninheritable virtuals
2879 make it through without complaint. */
2880 abstract_virtuals_error (field, type);
2882 if (TREE_CODE (t) == UNION_TYPE && cxx_dialect < cxx0x)
2885 int oldcount = errorcount;
2886 if (TYPE_NEEDS_CONSTRUCTING (type))
2887 error ("member %q+#D with constructor not allowed in union",
2889 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2890 error ("member %q+#D with destructor not allowed in union", field);
2891 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
2892 error ("member %q+#D with copy assignment operator not allowed in union",
2894 if (!warned && errorcount > oldcount)
2896 inform (DECL_SOURCE_LOCATION (field), "unrestricted unions "
2897 "only available with -std=c++0x or -std=gnu++0x");
2903 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2904 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2905 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2906 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
2907 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type)
2908 || !TYPE_HAS_COPY_ASSIGN (type));
2909 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type)
2910 || !TYPE_HAS_COPY_CTOR (type));
2911 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type);
2912 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type);
2913 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type)
2914 || TYPE_HAS_COMPLEX_DFLT (type));
2917 if (TYPE_HAS_COPY_CTOR (type)
2918 && !TYPE_HAS_CONST_COPY_CTOR (type))
2919 *cant_have_const_ctor = 1;
2921 if (TYPE_HAS_COPY_ASSIGN (type)
2922 && !TYPE_HAS_CONST_COPY_ASSIGN (type))
2923 *no_const_asn_ref = 1;
2925 if (DECL_INITIAL (field) != NULL_TREE)
2927 /* `build_class_init_list' does not recognize
2929 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2930 error ("multiple fields in union %qT initialized", t);
2931 *any_default_members = 1;
2935 /* Check the data members (both static and non-static), class-scoped
2936 typedefs, etc., appearing in the declaration of T. Issue
2937 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2938 declaration order) of access declarations; each TREE_VALUE in this
2939 list is a USING_DECL.
2941 In addition, set the following flags:
2944 The class is empty, i.e., contains no non-static data members.
2946 CANT_HAVE_CONST_CTOR_P
2947 This class cannot have an implicitly generated copy constructor
2948 taking a const reference.
2950 CANT_HAVE_CONST_ASN_REF
2951 This class cannot have an implicitly generated assignment
2952 operator taking a const reference.
2954 All of these flags should be initialized before calling this
2957 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2958 fields can be added by adding to this chain. */
2961 check_field_decls (tree t, tree *access_decls,
2962 int *cant_have_const_ctor_p,
2963 int *no_const_asn_ref_p)
2968 int any_default_members;
2970 int field_access = -1;
2972 /* Assume there are no access declarations. */
2973 *access_decls = NULL_TREE;
2974 /* Assume this class has no pointer members. */
2975 has_pointers = false;
2976 /* Assume none of the members of this class have default
2978 any_default_members = 0;
2980 for (field = &TYPE_FIELDS (t); *field; field = next)
2983 tree type = TREE_TYPE (x);
2984 int this_field_access;
2986 next = &DECL_CHAIN (x);
2988 if (TREE_CODE (x) == USING_DECL)
2990 /* Prune the access declaration from the list of fields. */
2991 *field = DECL_CHAIN (x);
2993 /* Save the access declarations for our caller. */
2994 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2996 /* Since we've reset *FIELD there's no reason to skip to the
3002 if (TREE_CODE (x) == TYPE_DECL
3003 || TREE_CODE (x) == TEMPLATE_DECL)
3006 /* If we've gotten this far, it's a data member, possibly static,
3007 or an enumerator. */
3008 DECL_CONTEXT (x) = t;
3010 /* When this goes into scope, it will be a non-local reference. */
3011 DECL_NONLOCAL (x) = 1;
3013 if (TREE_CODE (t) == UNION_TYPE)
3017 If a union contains a static data member, or a member of
3018 reference type, the program is ill-formed. */
3019 if (TREE_CODE (x) == VAR_DECL)
3021 error ("%q+D may not be static because it is a member of a union", x);
3024 if (TREE_CODE (type) == REFERENCE_TYPE)
3026 error ("%q+D may not have reference type %qT because"
3027 " it is a member of a union",
3033 /* Perform error checking that did not get done in
3035 if (TREE_CODE (type) == FUNCTION_TYPE)
3037 error ("field %q+D invalidly declared function type", x);
3038 type = build_pointer_type (type);
3039 TREE_TYPE (x) = type;
3041 else if (TREE_CODE (type) == METHOD_TYPE)
3043 error ("field %q+D invalidly declared method type", x);
3044 type = build_pointer_type (type);
3045 TREE_TYPE (x) = type;
3048 if (type == error_mark_node)
3051 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
3054 /* Now it can only be a FIELD_DECL. */
3056 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3057 CLASSTYPE_NON_AGGREGATE (t) = 1;
3059 /* If at least one non-static data member is non-literal, the whole
3060 class becomes non-literal. */
3061 if (!literal_type_p (type))
3062 CLASSTYPE_LITERAL_P (t) = false;
3064 /* A standard-layout class is a class that:
3066 has the same access control (Clause 11) for all non-static data members,
3068 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3069 if (field_access == -1)
3070 field_access = this_field_access;
3071 else if (this_field_access != field_access)
3072 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3074 /* If this is of reference type, check if it needs an init. */
3075 if (TREE_CODE (type) == REFERENCE_TYPE)
3077 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3078 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3079 if (DECL_INITIAL (x) == NULL_TREE)
3080 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3082 /* ARM $12.6.2: [A member initializer list] (or, for an
3083 aggregate, initialization by a brace-enclosed list) is the
3084 only way to initialize nonstatic const and reference
3086 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3087 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3090 type = strip_array_types (type);
3092 if (TYPE_PACKED (t))
3094 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3098 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3102 else if (DECL_C_BIT_FIELD (x)
3103 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3104 DECL_PACKED (x) = 1;
3107 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3108 /* We don't treat zero-width bitfields as making a class
3113 /* The class is non-empty. */
3114 CLASSTYPE_EMPTY_P (t) = 0;
3115 /* The class is not even nearly empty. */
3116 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3117 /* If one of the data members contains an empty class,
3119 if (CLASS_TYPE_P (type)
3120 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3121 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3124 /* This is used by -Weffc++ (see below). Warn only for pointers
3125 to members which might hold dynamic memory. So do not warn
3126 for pointers to functions or pointers to members. */
3127 if (TYPE_PTR_P (type)
3128 && !TYPE_PTRFN_P (type)
3129 && !TYPE_PTR_TO_MEMBER_P (type))
3130 has_pointers = true;
3132 if (CLASS_TYPE_P (type))
3134 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3135 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3136 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3137 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3140 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3141 CLASSTYPE_HAS_MUTABLE (t) = 1;
3143 if (! layout_pod_type_p (type))
3144 /* DR 148 now allows pointers to members (which are POD themselves),
3145 to be allowed in POD structs. */
3146 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3148 if (!std_layout_type_p (type))
3149 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3151 if (! zero_init_p (type))
3152 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3154 /* We set DECL_C_BIT_FIELD in grokbitfield.
3155 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3156 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3157 check_field_decl (x, t,
3158 cant_have_const_ctor_p,
3160 &any_default_members);
3162 /* If any field is const, the structure type is pseudo-const. */
3163 if (CP_TYPE_CONST_P (type))
3165 C_TYPE_FIELDS_READONLY (t) = 1;
3166 if (DECL_INITIAL (x) == NULL_TREE)
3167 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3169 /* ARM $12.6.2: [A member initializer list] (or, for an
3170 aggregate, initialization by a brace-enclosed list) is the
3171 only way to initialize nonstatic const and reference
3173 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3174 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3176 /* A field that is pseudo-const makes the structure likewise. */
3177 else if (CLASS_TYPE_P (type))
3179 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3180 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3181 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3182 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3185 /* Core issue 80: A nonstatic data member is required to have a
3186 different name from the class iff the class has a
3187 user-declared constructor. */
3188 if (constructor_name_p (DECL_NAME (x), t)
3189 && TYPE_HAS_USER_CONSTRUCTOR (t))
3190 permerror (input_location, "field %q+#D with same name as class", x);
3193 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3194 it should also define a copy constructor and an assignment operator to
3195 implement the correct copy semantic (deep vs shallow, etc.). As it is
3196 not feasible to check whether the constructors do allocate dynamic memory
3197 and store it within members, we approximate the warning like this:
3199 -- Warn only if there are members which are pointers
3200 -- Warn only if there is a non-trivial constructor (otherwise,
3201 there cannot be memory allocated).
3202 -- Warn only if there is a non-trivial destructor. We assume that the
3203 user at least implemented the cleanup correctly, and a destructor
3204 is needed to free dynamic memory.
3206 This seems enough for practical purposes. */
3209 && TYPE_HAS_USER_CONSTRUCTOR (t)
3210 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3211 && !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
3213 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3215 if (! TYPE_HAS_COPY_CTOR (t))
3217 warning (OPT_Weffc__,
3218 " but does not override %<%T(const %T&)%>", t, t);
3219 if (!TYPE_HAS_COPY_ASSIGN (t))
3220 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3222 else if (! TYPE_HAS_COPY_ASSIGN (t))
3223 warning (OPT_Weffc__,
3224 " but does not override %<operator=(const %T&)%>", t);
3227 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3229 TYPE_PACKED (t) = 0;
3231 /* Check anonymous struct/anonymous union fields. */
3232 finish_struct_anon (t);
3234 /* We've built up the list of access declarations in reverse order.
3236 *access_decls = nreverse (*access_decls);
3239 /* If TYPE is an empty class type, records its OFFSET in the table of
3243 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3247 if (!is_empty_class (type))
3250 /* Record the location of this empty object in OFFSETS. */
3251 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3253 n = splay_tree_insert (offsets,
3254 (splay_tree_key) offset,
3255 (splay_tree_value) NULL_TREE);
3256 n->value = ((splay_tree_value)
3257 tree_cons (NULL_TREE,
3264 /* Returns nonzero if TYPE is an empty class type and there is
3265 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3268 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3273 if (!is_empty_class (type))
3276 /* Record the location of this empty object in OFFSETS. */
3277 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3281 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3282 if (same_type_p (TREE_VALUE (t), type))
3288 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3289 F for every subobject, passing it the type, offset, and table of
3290 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3293 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3294 than MAX_OFFSET will not be walked.
3296 If F returns a nonzero value, the traversal ceases, and that value
3297 is returned. Otherwise, returns zero. */
3300 walk_subobject_offsets (tree type,
3301 subobject_offset_fn f,
3308 tree type_binfo = NULL_TREE;
3310 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3312 if (max_offset && INT_CST_LT (max_offset, offset))
3315 if (type == error_mark_node)
3320 if (abi_version_at_least (2))
3322 type = BINFO_TYPE (type);
3325 if (CLASS_TYPE_P (type))
3331 /* Avoid recursing into objects that are not interesting. */
3332 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3335 /* Record the location of TYPE. */
3336 r = (*f) (type, offset, offsets);
3340 /* Iterate through the direct base classes of TYPE. */
3342 type_binfo = TYPE_BINFO (type);
3343 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3347 if (abi_version_at_least (2)
3348 && BINFO_VIRTUAL_P (binfo))
3352 && BINFO_VIRTUAL_P (binfo)
3353 && !BINFO_PRIMARY_P (binfo))
3356 if (!abi_version_at_least (2))
3357 binfo_offset = size_binop (PLUS_EXPR,
3359 BINFO_OFFSET (binfo));
3363 /* We cannot rely on BINFO_OFFSET being set for the base
3364 class yet, but the offsets for direct non-virtual
3365 bases can be calculated by going back to the TYPE. */
3366 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3367 binfo_offset = size_binop (PLUS_EXPR,
3369 BINFO_OFFSET (orig_binfo));
3372 r = walk_subobject_offsets (binfo,
3377 (abi_version_at_least (2)
3378 ? /*vbases_p=*/0 : vbases_p));
3383 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3386 VEC(tree,gc) *vbases;
3388 /* Iterate through the virtual base classes of TYPE. In G++
3389 3.2, we included virtual bases in the direct base class
3390 loop above, which results in incorrect results; the
3391 correct offsets for virtual bases are only known when
3392 working with the most derived type. */
3394 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3395 VEC_iterate (tree, vbases, ix, binfo); ix++)
3397 r = walk_subobject_offsets (binfo,
3399 size_binop (PLUS_EXPR,
3401 BINFO_OFFSET (binfo)),
3410 /* We still have to walk the primary base, if it is
3411 virtual. (If it is non-virtual, then it was walked
3413 tree vbase = get_primary_binfo (type_binfo);
3415 if (vbase && BINFO_VIRTUAL_P (vbase)
3416 && BINFO_PRIMARY_P (vbase)
3417 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3419 r = (walk_subobject_offsets
3421 offsets, max_offset, /*vbases_p=*/0));
3428 /* Iterate through the fields of TYPE. */
3429 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
3430 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3434 if (abi_version_at_least (2))
3435 field_offset = byte_position (field);
3437 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3438 field_offset = DECL_FIELD_OFFSET (field);
3440 r = walk_subobject_offsets (TREE_TYPE (field),
3442 size_binop (PLUS_EXPR,
3452 else if (TREE_CODE (type) == ARRAY_TYPE)
3454 tree element_type = strip_array_types (type);
3455 tree domain = TYPE_DOMAIN (type);
3458 /* Avoid recursing into objects that are not interesting. */
3459 if (!CLASS_TYPE_P (element_type)
3460 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3463 /* Step through each of the elements in the array. */
3464 for (index = size_zero_node;
3465 /* G++ 3.2 had an off-by-one error here. */
3466 (abi_version_at_least (2)
3467 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3468 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3469 index = size_binop (PLUS_EXPR, index, size_one_node))
3471 r = walk_subobject_offsets (TREE_TYPE (type),
3479 offset = size_binop (PLUS_EXPR, offset,
3480 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3481 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3482 there's no point in iterating through the remaining
3483 elements of the array. */
3484 if (max_offset && INT_CST_LT (max_offset, offset))
3492 /* Record all of the empty subobjects of TYPE (either a type or a
3493 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3494 is being placed at OFFSET; otherwise, it is a base class that is
3495 being placed at OFFSET. */
3498 record_subobject_offsets (tree type,
3501 bool is_data_member)
3504 /* If recording subobjects for a non-static data member or a
3505 non-empty base class , we do not need to record offsets beyond
3506 the size of the biggest empty class. Additional data members
3507 will go at the end of the class. Additional base classes will go
3508 either at offset zero (if empty, in which case they cannot
3509 overlap with offsets past the size of the biggest empty class) or
3510 at the end of the class.
3512 However, if we are placing an empty base class, then we must record
3513 all offsets, as either the empty class is at offset zero (where
3514 other empty classes might later be placed) or at the end of the
3515 class (where other objects might then be placed, so other empty
3516 subobjects might later overlap). */
3518 || !is_empty_class (BINFO_TYPE (type)))
3519 max_offset = sizeof_biggest_empty_class;
3521 max_offset = NULL_TREE;
3522 walk_subobject_offsets (type, record_subobject_offset, offset,
3523 offsets, max_offset, is_data_member);
3526 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3527 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3528 virtual bases of TYPE are examined. */
3531 layout_conflict_p (tree type,
3536 splay_tree_node max_node;
3538 /* Get the node in OFFSETS that indicates the maximum offset where
3539 an empty subobject is located. */
3540 max_node = splay_tree_max (offsets);
3541 /* If there aren't any empty subobjects, then there's no point in
3542 performing this check. */
3546 return walk_subobject_offsets (type, check_subobject_offset, offset,
3547 offsets, (tree) (max_node->key),
3551 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3552 non-static data member of the type indicated by RLI. BINFO is the
3553 binfo corresponding to the base subobject, OFFSETS maps offsets to
3554 types already located at those offsets. This function determines
3555 the position of the DECL. */
3558 layout_nonempty_base_or_field (record_layout_info rli,
3563 tree offset = NULL_TREE;
3569 /* For the purposes of determining layout conflicts, we want to
3570 use the class type of BINFO; TREE_TYPE (DECL) will be the
3571 CLASSTYPE_AS_BASE version, which does not contain entries for
3572 zero-sized bases. */
3573 type = TREE_TYPE (binfo);
3578 type = TREE_TYPE (decl);
3582 /* Try to place the field. It may take more than one try if we have
3583 a hard time placing the field without putting two objects of the
3584 same type at the same address. */
3587 struct record_layout_info_s old_rli = *rli;
3589 /* Place this field. */
3590 place_field (rli, decl);
3591 offset = byte_position (decl);
3593 /* We have to check to see whether or not there is already
3594 something of the same type at the offset we're about to use.
3595 For example, consider:
3598 struct T : public S { int i; };
3599 struct U : public S, public T {};
3601 Here, we put S at offset zero in U. Then, we can't put T at
3602 offset zero -- its S component would be at the same address
3603 as the S we already allocated. So, we have to skip ahead.
3604 Since all data members, including those whose type is an
3605 empty class, have nonzero size, any overlap can happen only
3606 with a direct or indirect base-class -- it can't happen with
3608 /* In a union, overlap is permitted; all members are placed at
3610 if (TREE_CODE (rli->t) == UNION_TYPE)
3612 /* G++ 3.2 did not check for overlaps when placing a non-empty
3614 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3616 if (layout_conflict_p (field_p ? type : binfo, offset,
3619 /* Strip off the size allocated to this field. That puts us
3620 at the first place we could have put the field with
3621 proper alignment. */
3624 /* Bump up by the alignment required for the type. */
3626 = size_binop (PLUS_EXPR, rli->bitpos,
3628 ? CLASSTYPE_ALIGN (type)
3629 : TYPE_ALIGN (type)));
3630 normalize_rli (rli);
3633 /* There was no conflict. We're done laying out this field. */
3637 /* Now that we know where it will be placed, update its
3639 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3640 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3641 this point because their BINFO_OFFSET is copied from another
3642 hierarchy. Therefore, we may not need to add the entire
3644 propagate_binfo_offsets (binfo,
3645 size_diffop_loc (input_location,
3646 convert (ssizetype, offset),
3648 BINFO_OFFSET (binfo))));
3651 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3654 empty_base_at_nonzero_offset_p (tree type,
3656 splay_tree offsets ATTRIBUTE_UNUSED)
3658 return is_empty_class (type) && !integer_zerop (offset);
3661 /* Layout the empty base BINFO. EOC indicates the byte currently just
3662 past the end of the class, and should be correctly aligned for a
3663 class of the type indicated by BINFO; OFFSETS gives the offsets of
3664 the empty bases allocated so far. T is the most derived
3665 type. Return nonzero iff we added it at the end. */
3668 layout_empty_base (record_layout_info rli, tree binfo,
3669 tree eoc, splay_tree offsets)
3672 tree basetype = BINFO_TYPE (binfo);
3675 /* This routine should only be used for empty classes. */
3676 gcc_assert (is_empty_class (basetype));
3677 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3679 if (!integer_zerop (BINFO_OFFSET (binfo)))
3681 if (abi_version_at_least (2))
3682 propagate_binfo_offsets
3683 (binfo, size_diffop_loc (input_location,
3684 size_zero_node, BINFO_OFFSET (binfo)));
3687 "offset of empty base %qT may not be ABI-compliant and may"
3688 "change in a future version of GCC",
3689 BINFO_TYPE (binfo));
3692 /* This is an empty base class. We first try to put it at offset
3694 if (layout_conflict_p (binfo,
3695 BINFO_OFFSET (binfo),
3699 /* That didn't work. Now, we move forward from the next
3700 available spot in the class. */
3702 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3705 if (!layout_conflict_p (binfo,
3706 BINFO_OFFSET (binfo),
3709 /* We finally found a spot where there's no overlap. */
3712 /* There's overlap here, too. Bump along to the next spot. */
3713 propagate_binfo_offsets (binfo, alignment);
3717 if (CLASSTYPE_USER_ALIGN (basetype))
3719 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3721 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3722 TYPE_USER_ALIGN (rli->t) = 1;
3728 /* Layout the base given by BINFO in the class indicated by RLI.
3729 *BASE_ALIGN is a running maximum of the alignments of
3730 any base class. OFFSETS gives the location of empty base
3731 subobjects. T is the most derived type. Return nonzero if the new
3732 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3733 *NEXT_FIELD, unless BINFO is for an empty base class.
3735 Returns the location at which the next field should be inserted. */
3738 build_base_field (record_layout_info rli, tree binfo,
3739 splay_tree offsets, tree *next_field)
3742 tree basetype = BINFO_TYPE (binfo);
3744 if (!COMPLETE_TYPE_P (basetype))
3745 /* This error is now reported in xref_tag, thus giving better
3746 location information. */
3749 /* Place the base class. */
3750 if (!is_empty_class (basetype))
3754 /* The containing class is non-empty because it has a non-empty
3756 CLASSTYPE_EMPTY_P (t) = 0;
3758 /* Create the FIELD_DECL. */
3759 decl = build_decl (input_location,
3760 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3761 DECL_ARTIFICIAL (decl) = 1;
3762 DECL_IGNORED_P (decl) = 1;
3763 DECL_FIELD_CONTEXT (decl) = t;
3764 if (CLASSTYPE_AS_BASE (basetype))
3766 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3767 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3768 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3769 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3770 DECL_MODE (decl) = TYPE_MODE (basetype);
3771 DECL_FIELD_IS_BASE (decl) = 1;
3773 /* Try to place the field. It may take more than one try if we
3774 have a hard time placing the field without putting two
3775 objects of the same type at the same address. */
3776 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3777 /* Add the new FIELD_DECL to the list of fields for T. */
3778 DECL_CHAIN (decl) = *next_field;
3780 next_field = &DECL_CHAIN (decl);
3788 /* On some platforms (ARM), even empty classes will not be
3790 eoc = round_up_loc (input_location,
3791 rli_size_unit_so_far (rli),
3792 CLASSTYPE_ALIGN_UNIT (basetype));
3793 atend = layout_empty_base (rli, binfo, eoc, offsets);
3794 /* A nearly-empty class "has no proper base class that is empty,
3795 not morally virtual, and at an offset other than zero." */
3796 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3799 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3800 /* The check above (used in G++ 3.2) is insufficient because
3801 an empty class placed at offset zero might itself have an
3802 empty base at a nonzero offset. */
3803 else if (walk_subobject_offsets (basetype,
3804 empty_base_at_nonzero_offset_p,
3807 /*max_offset=*/NULL_TREE,
3810 if (abi_version_at_least (2))
3811 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3814 "class %qT will be considered nearly empty in a "
3815 "future version of GCC", t);
3819 /* We do not create a FIELD_DECL for empty base classes because
3820 it might overlap some other field. We want to be able to
3821 create CONSTRUCTORs for the class by iterating over the
3822 FIELD_DECLs, and the back end does not handle overlapping
3825 /* An empty virtual base causes a class to be non-empty
3826 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3827 here because that was already done when the virtual table
3828 pointer was created. */
3831 /* Record the offsets of BINFO and its base subobjects. */
3832 record_subobject_offsets (binfo,
3833 BINFO_OFFSET (binfo),
3835 /*is_data_member=*/false);
3840 /* Layout all of the non-virtual base classes. Record empty
3841 subobjects in OFFSETS. T is the most derived type. Return nonzero
3842 if the type cannot be nearly empty. The fields created
3843 corresponding to the base classes will be inserted at
3847 build_base_fields (record_layout_info rli,
3848 splay_tree offsets, tree *next_field)
3850 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3853 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3856 /* The primary base class is always allocated first. */
3857 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3858 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3859 offsets, next_field);
3861 /* Now allocate the rest of the bases. */
3862 for (i = 0; i < n_baseclasses; ++i)
3866 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3868 /* The primary base was already allocated above, so we don't
3869 need to allocate it again here. */
3870 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3873 /* Virtual bases are added at the end (a primary virtual base
3874 will have already been added). */
3875 if (BINFO_VIRTUAL_P (base_binfo))
3878 next_field = build_base_field (rli, base_binfo,
3879 offsets, next_field);
3883 /* Go through the TYPE_METHODS of T issuing any appropriate
3884 diagnostics, figuring out which methods override which other
3885 methods, and so forth. */
3888 check_methods (tree t)
3892 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
3894 check_for_override (x, t);
3895 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3896 error ("initializer specified for non-virtual method %q+D", x);
3897 /* The name of the field is the original field name
3898 Save this in auxiliary field for later overloading. */
3899 if (DECL_VINDEX (x))
3901 TYPE_POLYMORPHIC_P (t) = 1;
3902 if (DECL_PURE_VIRTUAL_P (x))
3903 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3905 /* All user-provided destructors are non-trivial.
3906 Constructors and assignment ops are handled in
3907 grok_special_member_properties. */
3908 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
3909 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3913 /* FN is a constructor or destructor. Clone the declaration to create
3914 a specialized in-charge or not-in-charge version, as indicated by
3918 build_clone (tree fn, tree name)
3923 /* Copy the function. */
3924 clone = copy_decl (fn);
3925 /* Reset the function name. */
3926 DECL_NAME (clone) = name;
3927 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3928 /* Remember where this function came from. */
3929 DECL_ABSTRACT_ORIGIN (clone) = fn;
3930 /* Make it easy to find the CLONE given the FN. */
3931 DECL_CHAIN (clone) = DECL_CHAIN (fn);
3932 DECL_CHAIN (fn) = clone;
3934 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3935 if (TREE_CODE (clone) == TEMPLATE_DECL)
3937 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3938 DECL_TEMPLATE_RESULT (clone) = result;
3939 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3940 DECL_TI_TEMPLATE (result) = clone;
3941 TREE_TYPE (clone) = TREE_TYPE (result);
3945 DECL_CLONED_FUNCTION (clone) = fn;
3946 /* There's no pending inline data for this function. */
3947 DECL_PENDING_INLINE_INFO (clone) = NULL;
3948 DECL_PENDING_INLINE_P (clone) = 0;
3950 /* The base-class destructor is not virtual. */
3951 if (name == base_dtor_identifier)
3953 DECL_VIRTUAL_P (clone) = 0;
3954 if (TREE_CODE (clone) != TEMPLATE_DECL)
3955 DECL_VINDEX (clone) = NULL_TREE;
3958 /* If there was an in-charge parameter, drop it from the function
3960 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3966 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3967 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3968 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3969 /* Skip the `this' parameter. */
3970 parmtypes = TREE_CHAIN (parmtypes);
3971 /* Skip the in-charge parameter. */
3972 parmtypes = TREE_CHAIN (parmtypes);
3973 /* And the VTT parm, in a complete [cd]tor. */
3974 if (DECL_HAS_VTT_PARM_P (fn)
3975 && ! DECL_NEEDS_VTT_PARM_P (clone))
3976 parmtypes = TREE_CHAIN (parmtypes);
3977 /* If this is subobject constructor or destructor, add the vtt
3980 = build_method_type_directly (basetype,
3981 TREE_TYPE (TREE_TYPE (clone)),
3984 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3987 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3988 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3991 /* Copy the function parameters. */
3992 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3993 /* Remove the in-charge parameter. */
3994 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3996 DECL_CHAIN (DECL_ARGUMENTS (clone))
3997 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
3998 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
4000 /* And the VTT parm, in a complete [cd]tor. */
4001 if (DECL_HAS_VTT_PARM_P (fn))
4003 if (DECL_NEEDS_VTT_PARM_P (clone))
4004 DECL_HAS_VTT_PARM_P (clone) = 1;
4007 DECL_CHAIN (DECL_ARGUMENTS (clone))
4008 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4009 DECL_HAS_VTT_PARM_P (clone) = 0;
4013 for (parms = DECL_ARGUMENTS (clone); parms; parms = DECL_CHAIN (parms))
4015 DECL_CONTEXT (parms) = clone;
4016 cxx_dup_lang_specific_decl (parms);
4019 /* Create the RTL for this function. */
4020 SET_DECL_RTL (clone, NULL);
4021 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
4024 note_decl_for_pch (clone);
4029 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4030 not invoke this function directly.
4032 For a non-thunk function, returns the address of the slot for storing
4033 the function it is a clone of. Otherwise returns NULL_TREE.
4035 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4036 cloned_function is unset. This is to support the separate
4037 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4038 on a template makes sense, but not the former. */
4041 decl_cloned_function_p (const_tree decl, bool just_testing)
4045 decl = STRIP_TEMPLATE (decl);
4047 if (TREE_CODE (decl) != FUNCTION_DECL
4048 || !DECL_LANG_SPECIFIC (decl)
4049 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
4051 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4053 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
4059 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
4060 if (just_testing && *ptr == NULL_TREE)
4066 /* Produce declarations for all appropriate clones of FN. If
4067 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4068 CLASTYPE_METHOD_VEC as well. */
4071 clone_function_decl (tree fn, int update_method_vec_p)
4075 /* Avoid inappropriate cloning. */
4077 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (fn)))
4080 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4082 /* For each constructor, we need two variants: an in-charge version
4083 and a not-in-charge version. */
4084 clone = build_clone (fn, complete_ctor_identifier);
4085 if (update_method_vec_p)
4086 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4087 clone = build_clone (fn, base_ctor_identifier);
4088 if (update_method_vec_p)
4089 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4093 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4095 /* For each destructor, we need three variants: an in-charge
4096 version, a not-in-charge version, and an in-charge deleting
4097 version. We clone the deleting version first because that
4098 means it will go second on the TYPE_METHODS list -- and that
4099 corresponds to the correct layout order in the virtual
4102 For a non-virtual destructor, we do not build a deleting
4104 if (DECL_VIRTUAL_P (fn))
4106 clone = build_clone (fn, deleting_dtor_identifier);
4107 if (update_method_vec_p)
4108 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4110 clone = build_clone (fn, complete_dtor_identifier);
4111 if (update_method_vec_p)
4112 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4113 clone = build_clone (fn, base_dtor_identifier);
4114 if (update_method_vec_p)
4115 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4118 /* Note that this is an abstract function that is never emitted. */
4119 DECL_ABSTRACT (fn) = 1;
4122 /* DECL is an in charge constructor, which is being defined. This will
4123 have had an in class declaration, from whence clones were
4124 declared. An out-of-class definition can specify additional default
4125 arguments. As it is the clones that are involved in overload
4126 resolution, we must propagate the information from the DECL to its
4130 adjust_clone_args (tree decl)
4134 for (clone = DECL_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4135 clone = DECL_CHAIN (clone))
4137 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4138 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4139 tree decl_parms, clone_parms;
4141 clone_parms = orig_clone_parms;
4143 /* Skip the 'this' parameter. */
4144 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4145 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4147 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4148 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4149 if (DECL_HAS_VTT_PARM_P (decl))
4150 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4152 clone_parms = orig_clone_parms;
4153 if (DECL_HAS_VTT_PARM_P (clone))
4154 clone_parms = TREE_CHAIN (clone_parms);
4156 for (decl_parms = orig_decl_parms; decl_parms;
4157 decl_parms = TREE_CHAIN (decl_parms),
4158 clone_parms = TREE_CHAIN (clone_parms))
4160 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4161 TREE_TYPE (clone_parms)));
4163 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4165 /* A default parameter has been added. Adjust the
4166 clone's parameters. */
4167 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4168 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4169 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4172 clone_parms = orig_decl_parms;
4174 if (DECL_HAS_VTT_PARM_P (clone))
4176 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4177 TREE_VALUE (orig_clone_parms),
4179 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4181 type = build_method_type_directly (basetype,
4182 TREE_TYPE (TREE_TYPE (clone)),
4185 type = build_exception_variant (type, exceptions);
4187 type = cp_build_type_attribute_variant (type, attrs);
4188 TREE_TYPE (clone) = type;
4190 clone_parms = NULL_TREE;
4194 gcc_assert (!clone_parms);
4198 /* For each of the constructors and destructors in T, create an
4199 in-charge and not-in-charge variant. */
4202 clone_constructors_and_destructors (tree t)
4206 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4208 if (!CLASSTYPE_METHOD_VEC (t))
4211 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4212 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4213 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4214 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4217 /* Returns true iff class T has a user-defined constructor other than
4218 the default constructor. */
4221 type_has_user_nondefault_constructor (tree t)
4225 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4228 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4230 tree fn = OVL_CURRENT (fns);
4231 if (!DECL_ARTIFICIAL (fn)
4232 && (TREE_CODE (fn) == TEMPLATE_DECL
4233 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4241 /* Returns the defaulted constructor if T has one. Otherwise, returns
4245 in_class_defaulted_default_constructor (tree t)
4249 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4252 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4254 tree fn = OVL_CURRENT (fns);
4256 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4258 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4259 while (args && TREE_PURPOSE (args))
4260 args = TREE_CHAIN (args);
4261 if (!args || args == void_list_node)
4269 /* Returns true iff FN is a user-provided function, i.e. user-declared
4270 and not defaulted at its first declaration; or explicit, private,
4271 protected, or non-const. */
4274 user_provided_p (tree fn)
4276 if (TREE_CODE (fn) == TEMPLATE_DECL)
4279 return (!DECL_ARTIFICIAL (fn)
4280 && !DECL_DEFAULTED_IN_CLASS_P (fn));
4283 /* Returns true iff class T has a user-provided constructor. */
4286 type_has_user_provided_constructor (tree t)
4290 if (!CLASS_TYPE_P (t))
4293 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4296 /* This can happen in error cases; avoid crashing. */
4297 if (!CLASSTYPE_METHOD_VEC (t))
4300 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4301 if (user_provided_p (OVL_CURRENT (fns)))
4307 /* Returns true iff class T has a user-provided default constructor. */
4310 type_has_user_provided_default_constructor (tree t)
4314 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4317 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4319 tree fn = OVL_CURRENT (fns);
4320 if (TREE_CODE (fn) == FUNCTION_DECL
4321 && user_provided_p (fn)
4322 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)))
4329 /* Returns true iff for class T, a synthesized default constructor
4330 would be constexpr. */
4333 synthesized_default_constructor_is_constexpr (tree t)
4335 /* A defaulted default constructor is constexpr
4336 if there is nothing to initialize. */
4337 /* FIXME adjust for non-static data member initializers. */
4338 return is_really_empty_class (t);
4341 /* Returns true iff class T has a constexpr default constructor. */
4344 type_has_constexpr_default_constructor (tree t)
4348 if (!CLASS_TYPE_P (t))
4350 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t))
4351 return synthesized_default_constructor_is_constexpr (t);
4352 fns = get_default_ctor (t);
4353 return (fns && DECL_DECLARED_CONSTEXPR_P (fns));
4356 /* Returns true iff class TYPE has a virtual destructor. */
4359 type_has_virtual_destructor (tree type)
4363 if (!CLASS_TYPE_P (type))
4366 gcc_assert (COMPLETE_TYPE_P (type));
4367 dtor = CLASSTYPE_DESTRUCTORS (type);
4368 return (dtor && DECL_VIRTUAL_P (dtor));
4371 /* Returns true iff class T has a move constructor. */
4374 type_has_move_constructor (tree t)
4378 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4380 gcc_assert (COMPLETE_TYPE_P (t));
4381 lazily_declare_fn (sfk_move_constructor, t);
4384 if (!CLASSTYPE_METHOD_VEC (t))
4387 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4388 if (move_fn_p (OVL_CURRENT (fns)))
4394 /* Returns true iff class T has a move assignment operator. */
4397 type_has_move_assign (tree t)
4401 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4403 gcc_assert (COMPLETE_TYPE_P (t));
4404 lazily_declare_fn (sfk_move_assignment, t);
4407 for (fns = lookup_fnfields_slot (t, ansi_assopname (NOP_EXPR));
4408 fns; fns = OVL_NEXT (fns))
4409 if (move_fn_p (OVL_CURRENT (fns)))
4415 /* Remove all zero-width bit-fields from T. */
4418 remove_zero_width_bit_fields (tree t)
4422 fieldsp = &TYPE_FIELDS (t);
4425 if (TREE_CODE (*fieldsp) == FIELD_DECL
4426 && DECL_C_BIT_FIELD (*fieldsp)
4427 /* We should not be confused by the fact that grokbitfield
4428 temporarily sets the width of the bit field into
4429 DECL_INITIAL (*fieldsp).
4430 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4432 && integer_zerop (DECL_SIZE (*fieldsp)))
4433 *fieldsp = DECL_CHAIN (*fieldsp);
4435 fieldsp = &DECL_CHAIN (*fieldsp);
4439 /* Returns TRUE iff we need a cookie when dynamically allocating an
4440 array whose elements have the indicated class TYPE. */
4443 type_requires_array_cookie (tree type)
4446 bool has_two_argument_delete_p = false;
4448 gcc_assert (CLASS_TYPE_P (type));
4450 /* If there's a non-trivial destructor, we need a cookie. In order
4451 to iterate through the array calling the destructor for each
4452 element, we'll have to know how many elements there are. */
4453 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4456 /* If the usual deallocation function is a two-argument whose second
4457 argument is of type `size_t', then we have to pass the size of
4458 the array to the deallocation function, so we will need to store
4460 fns = lookup_fnfields (TYPE_BINFO (type),
4461 ansi_opname (VEC_DELETE_EXPR),
4463 /* If there are no `operator []' members, or the lookup is
4464 ambiguous, then we don't need a cookie. */
4465 if (!fns || fns == error_mark_node)
4467 /* Loop through all of the functions. */
4468 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4473 /* Select the current function. */
4474 fn = OVL_CURRENT (fns);
4475 /* See if this function is a one-argument delete function. If
4476 it is, then it will be the usual deallocation function. */
4477 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4478 if (second_parm == void_list_node)
4480 /* Do not consider this function if its second argument is an
4484 /* Otherwise, if we have a two-argument function and the second
4485 argument is `size_t', it will be the usual deallocation
4486 function -- unless there is one-argument function, too. */
4487 if (TREE_CHAIN (second_parm) == void_list_node
4488 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4489 has_two_argument_delete_p = true;
4492 return has_two_argument_delete_p;
4495 /* Finish computing the `literal type' property of class type T.
4497 At this point, we have already processed base classes and
4498 non-static data members. We need to check whether the copy
4499 constructor is trivial, the destructor is trivial, and there
4500 is a trivial default constructor or at least one constexpr
4501 constructor other than the copy constructor. */
4504 finalize_literal_type_property (tree t)
4506 if (cxx_dialect < cxx0x
4507 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
4508 /* FIXME These constraints seem unnecessary; remove from standard.
4509 || !TYPE_HAS_TRIVIAL_COPY_CTOR (t)
4510 || TYPE_HAS_COMPLEX_MOVE_CTOR (t)*/ )
4511 CLASSTYPE_LITERAL_P (t) = false;
4512 else if (CLASSTYPE_LITERAL_P (t) && !TYPE_HAS_TRIVIAL_DFLT (t)
4513 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4514 CLASSTYPE_LITERAL_P (t) = false;
4516 if (!CLASSTYPE_LITERAL_P (t) && !CLASSTYPE_TEMPLATE_INSTANTIATION (t))
4519 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4520 if (DECL_DECLARED_CONSTEXPR_P (fn)
4521 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
4522 && !DECL_CONSTRUCTOR_P (fn))
4524 error ("enclosing class of %q+D is not a literal type", fn);
4525 DECL_DECLARED_CONSTEXPR_P (fn) = false;
4530 /* Check the validity of the bases and members declared in T. Add any
4531 implicitly-generated functions (like copy-constructors and
4532 assignment operators). Compute various flag bits (like
4533 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4534 level: i.e., independently of the ABI in use. */
4537 check_bases_and_members (tree t)
4539 /* Nonzero if the implicitly generated copy constructor should take
4540 a non-const reference argument. */
4541 int cant_have_const_ctor;
4542 /* Nonzero if the implicitly generated assignment operator
4543 should take a non-const reference argument. */
4544 int no_const_asn_ref;
4546 bool saved_complex_asn_ref;
4547 bool saved_nontrivial_dtor;
4550 /* By default, we use const reference arguments and generate default
4552 cant_have_const_ctor = 0;
4553 no_const_asn_ref = 0;
4555 /* Check all the base-classes. */
4556 check_bases (t, &cant_have_const_ctor,
4559 /* Check all the method declarations. */
4562 /* Save the initial values of these flags which only indicate whether
4563 or not the class has user-provided functions. As we analyze the
4564 bases and members we can set these flags for other reasons. */
4565 saved_complex_asn_ref = TYPE_HAS_COMPLEX_COPY_ASSIGN (t);
4566 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4568 /* Check all the data member declarations. We cannot call
4569 check_field_decls until we have called check_bases check_methods,
4570 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4571 being set appropriately. */
4572 check_field_decls (t, &access_decls,
4573 &cant_have_const_ctor,
4576 /* A nearly-empty class has to be vptr-containing; a nearly empty
4577 class contains just a vptr. */
4578 if (!TYPE_CONTAINS_VPTR_P (t))
4579 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4581 /* Do some bookkeeping that will guide the generation of implicitly
4582 declared member functions. */
4583 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4584 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4585 /* We need to call a constructor for this class if it has a
4586 user-provided constructor, or if the default constructor is going
4587 to initialize the vptr. (This is not an if-and-only-if;
4588 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4589 themselves need constructing.) */
4590 TYPE_NEEDS_CONSTRUCTING (t)
4591 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4594 An aggregate is an array or a class with no user-provided
4595 constructors ... and no virtual functions.
4597 Again, other conditions for being an aggregate are checked
4599 CLASSTYPE_NON_AGGREGATE (t)
4600 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4601 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4602 retain the old definition internally for ABI reasons. */
4603 CLASSTYPE_NON_LAYOUT_POD_P (t)
4604 |= (CLASSTYPE_NON_AGGREGATE (t)
4605 || saved_nontrivial_dtor || saved_complex_asn_ref);
4606 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
4607 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4608 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4609 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4611 /* If the class has no user-declared constructor, but does have
4612 non-static const or reference data members that can never be
4613 initialized, issue a warning. */
4614 if (warn_uninitialized
4615 /* Classes with user-declared constructors are presumed to
4616 initialize these members. */
4617 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4618 /* Aggregates can be initialized with brace-enclosed
4620 && CLASSTYPE_NON_AGGREGATE (t))
4624 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
4628 if (TREE_CODE (field) != FIELD_DECL)
4631 type = TREE_TYPE (field);
4632 if (TREE_CODE (type) == REFERENCE_TYPE)
4633 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4634 "in class without a constructor", field);
4635 else if (CP_TYPE_CONST_P (type)
4636 && (!CLASS_TYPE_P (type)
4637 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4638 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4639 "in class without a constructor", field);
4643 /* Synthesize any needed methods. */
4644 add_implicitly_declared_members (t,
4645 cant_have_const_ctor,
4648 /* Check defaulted declarations here so we have cant_have_const_ctor
4649 and don't need to worry about clones. */
4650 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4651 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4653 int copy = copy_fn_p (fn);
4657 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
4658 : !no_const_asn_ref);
4659 bool fn_const_p = (copy == 2);
4661 if (fn_const_p && !imp_const_p)
4662 /* If the function is defaulted outside the class, we just
4663 give the synthesis error. */
4664 error ("%q+D declared to take const reference, but implicit "
4665 "declaration would take non-const", fn);
4666 else if (imp_const_p && !fn_const_p)
4667 error ("%q+D declared to take non-const reference cannot be "
4668 "defaulted in the class body", fn);
4670 defaulted_late_check (fn);
4673 if (LAMBDA_TYPE_P (t))
4675 /* "The closure type associated with a lambda-expression has a deleted
4676 default constructor and a deleted copy assignment operator." */
4677 TYPE_NEEDS_CONSTRUCTING (t) = 1;
4678 TYPE_HAS_COMPLEX_DFLT (t) = 1;
4679 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
4680 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 0;
4682 /* "This class type is not an aggregate." */
4683 CLASSTYPE_NON_AGGREGATE (t) = 1;
4686 /* Compute the 'literal type' property before we
4687 do anything with non-static member functions. */
4688 finalize_literal_type_property (t);
4690 /* Create the in-charge and not-in-charge variants of constructors
4692 clone_constructors_and_destructors (t);
4694 /* Process the using-declarations. */
4695 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4696 handle_using_decl (TREE_VALUE (access_decls), t);
4698 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4699 finish_struct_methods (t);
4701 /* Figure out whether or not we will need a cookie when dynamically
4702 allocating an array of this type. */
4703 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4704 = type_requires_array_cookie (t);
4707 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4708 accordingly. If a new vfield was created (because T doesn't have a
4709 primary base class), then the newly created field is returned. It
4710 is not added to the TYPE_FIELDS list; it is the caller's
4711 responsibility to do that. Accumulate declared virtual functions
4715 create_vtable_ptr (tree t, tree* virtuals_p)
4719 /* Collect the virtual functions declared in T. */
4720 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4721 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4722 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4724 tree new_virtual = make_node (TREE_LIST);
4726 BV_FN (new_virtual) = fn;
4727 BV_DELTA (new_virtual) = integer_zero_node;
4728 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4730 TREE_CHAIN (new_virtual) = *virtuals_p;
4731 *virtuals_p = new_virtual;
4734 /* If we couldn't find an appropriate base class, create a new field
4735 here. Even if there weren't any new virtual functions, we might need a
4736 new virtual function table if we're supposed to include vptrs in
4737 all classes that need them. */
4738 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4740 /* We build this decl with vtbl_ptr_type_node, which is a
4741 `vtable_entry_type*'. It might seem more precise to use
4742 `vtable_entry_type (*)[N]' where N is the number of virtual
4743 functions. However, that would require the vtable pointer in
4744 base classes to have a different type than the vtable pointer
4745 in derived classes. We could make that happen, but that
4746 still wouldn't solve all the problems. In particular, the
4747 type-based alias analysis code would decide that assignments
4748 to the base class vtable pointer can't alias assignments to
4749 the derived class vtable pointer, since they have different
4750 types. Thus, in a derived class destructor, where the base
4751 class constructor was inlined, we could generate bad code for
4752 setting up the vtable pointer.
4754 Therefore, we use one type for all vtable pointers. We still
4755 use a type-correct type; it's just doesn't indicate the array
4756 bounds. That's better than using `void*' or some such; it's
4757 cleaner, and it let's the alias analysis code know that these
4758 stores cannot alias stores to void*! */
4761 field = build_decl (input_location,
4762 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4763 DECL_VIRTUAL_P (field) = 1;
4764 DECL_ARTIFICIAL (field) = 1;
4765 DECL_FIELD_CONTEXT (field) = t;
4766 DECL_FCONTEXT (field) = t;
4767 if (TYPE_PACKED (t))
4768 DECL_PACKED (field) = 1;
4770 TYPE_VFIELD (t) = field;
4772 /* This class is non-empty. */
4773 CLASSTYPE_EMPTY_P (t) = 0;
4781 /* Add OFFSET to all base types of BINFO which is a base in the
4782 hierarchy dominated by T.
4784 OFFSET, which is a type offset, is number of bytes. */
4787 propagate_binfo_offsets (tree binfo, tree offset)
4793 /* Update BINFO's offset. */
4794 BINFO_OFFSET (binfo)
4795 = convert (sizetype,
4796 size_binop (PLUS_EXPR,
4797 convert (ssizetype, BINFO_OFFSET (binfo)),
4800 /* Find the primary base class. */
4801 primary_binfo = get_primary_binfo (binfo);
4803 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4804 propagate_binfo_offsets (primary_binfo, offset);
4806 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4808 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4810 /* Don't do the primary base twice. */
4811 if (base_binfo == primary_binfo)
4814 if (BINFO_VIRTUAL_P (base_binfo))
4817 propagate_binfo_offsets (base_binfo, offset);
4821 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4822 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4823 empty subobjects of T. */
4826 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4830 bool first_vbase = true;
4833 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4836 if (!abi_version_at_least(2))
4838 /* In G++ 3.2, we incorrectly rounded the size before laying out
4839 the virtual bases. */
4840 finish_record_layout (rli, /*free_p=*/false);
4841 #ifdef STRUCTURE_SIZE_BOUNDARY
4842 /* Packed structures don't need to have minimum size. */
4843 if (! TYPE_PACKED (t))
4844 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4846 rli->offset = TYPE_SIZE_UNIT (t);
4847 rli->bitpos = bitsize_zero_node;
4848 rli->record_align = TYPE_ALIGN (t);
4851 /* Find the last field. The artificial fields created for virtual
4852 bases will go after the last extant field to date. */
4853 next_field = &TYPE_FIELDS (t);
4855 next_field = &DECL_CHAIN (*next_field);
4857 /* Go through the virtual bases, allocating space for each virtual
4858 base that is not already a primary base class. These are
4859 allocated in inheritance graph order. */
4860 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4862 if (!BINFO_VIRTUAL_P (vbase))
4865 if (!BINFO_PRIMARY_P (vbase))
4867 tree basetype = TREE_TYPE (vbase);
4869 /* This virtual base is not a primary base of any class in the
4870 hierarchy, so we have to add space for it. */
4871 next_field = build_base_field (rli, vbase,
4872 offsets, next_field);
4874 /* If the first virtual base might have been placed at a
4875 lower address, had we started from CLASSTYPE_SIZE, rather
4876 than TYPE_SIZE, issue a warning. There can be both false
4877 positives and false negatives from this warning in rare
4878 cases; to deal with all the possibilities would probably
4879 require performing both layout algorithms and comparing
4880 the results which is not particularly tractable. */
4884 (size_binop (CEIL_DIV_EXPR,
4885 round_up_loc (input_location,
4887 CLASSTYPE_ALIGN (basetype)),
4889 BINFO_OFFSET (vbase))))
4891 "offset of virtual base %qT is not ABI-compliant and "
4892 "may change in a future version of GCC",
4895 first_vbase = false;
4900 /* Returns the offset of the byte just past the end of the base class
4904 end_of_base (tree binfo)
4908 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
4909 size = TYPE_SIZE_UNIT (char_type_node);
4910 else if (is_empty_class (BINFO_TYPE (binfo)))
4911 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4912 allocate some space for it. It cannot have virtual bases, so
4913 TYPE_SIZE_UNIT is fine. */
4914 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4916 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4918 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4921 /* Returns the offset of the byte just past the end of the base class
4922 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4923 only non-virtual bases are included. */
4926 end_of_class (tree t, int include_virtuals_p)
4928 tree result = size_zero_node;
4929 VEC(tree,gc) *vbases;
4935 for (binfo = TYPE_BINFO (t), i = 0;
4936 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4938 if (!include_virtuals_p
4939 && BINFO_VIRTUAL_P (base_binfo)
4940 && (!BINFO_PRIMARY_P (base_binfo)
4941 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4944 offset = end_of_base (base_binfo);
4945 if (INT_CST_LT_UNSIGNED (result, offset))
4949 /* G++ 3.2 did not check indirect virtual bases. */
4950 if (abi_version_at_least (2) && include_virtuals_p)
4951 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4952 VEC_iterate (tree, vbases, i, base_binfo); i++)
4954 offset = end_of_base (base_binfo);
4955 if (INT_CST_LT_UNSIGNED (result, offset))
4962 /* Warn about bases of T that are inaccessible because they are
4963 ambiguous. For example:
4966 struct T : public S {};
4967 struct U : public S, public T {};
4969 Here, `(S*) new U' is not allowed because there are two `S'
4973 warn_about_ambiguous_bases (tree t)
4976 VEC(tree,gc) *vbases;
4981 /* If there are no repeated bases, nothing can be ambiguous. */
4982 if (!CLASSTYPE_REPEATED_BASE_P (t))
4985 /* Check direct bases. */
4986 for (binfo = TYPE_BINFO (t), i = 0;
4987 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4989 basetype = BINFO_TYPE (base_binfo);
4991 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4992 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4996 /* Check for ambiguous virtual bases. */
4998 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4999 VEC_iterate (tree, vbases, i, binfo); i++)
5001 basetype = BINFO_TYPE (binfo);
5003 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5004 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
5009 /* Compare two INTEGER_CSTs K1 and K2. */
5012 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
5014 return tree_int_cst_compare ((tree) k1, (tree) k2);
5017 /* Increase the size indicated in RLI to account for empty classes
5018 that are "off the end" of the class. */
5021 include_empty_classes (record_layout_info rli)
5026 /* It might be the case that we grew the class to allocate a
5027 zero-sized base class. That won't be reflected in RLI, yet,
5028 because we are willing to overlay multiple bases at the same
5029 offset. However, now we need to make sure that RLI is big enough
5030 to reflect the entire class. */
5031 eoc = end_of_class (rli->t,
5032 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
5033 rli_size = rli_size_unit_so_far (rli);
5034 if (TREE_CODE (rli_size) == INTEGER_CST
5035 && INT_CST_LT_UNSIGNED (rli_size, eoc))
5037 if (!abi_version_at_least (2))
5038 /* In version 1 of the ABI, the size of a class that ends with
5039 a bitfield was not rounded up to a whole multiple of a
5040 byte. Because rli_size_unit_so_far returns only the number
5041 of fully allocated bytes, any extra bits were not included
5043 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
5045 /* The size should have been rounded to a whole byte. */
5046 gcc_assert (tree_int_cst_equal
5047 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
5049 = size_binop (PLUS_EXPR,
5051 size_binop (MULT_EXPR,
5052 convert (bitsizetype,
5053 size_binop (MINUS_EXPR,
5055 bitsize_int (BITS_PER_UNIT)));
5056 normalize_rli (rli);
5060 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
5061 BINFO_OFFSETs for all of the base-classes. Position the vtable
5062 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
5065 layout_class_type (tree t, tree *virtuals_p)
5067 tree non_static_data_members;
5070 record_layout_info rli;
5071 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
5072 types that appear at that offset. */
5073 splay_tree empty_base_offsets;
5074 /* True if the last field layed out was a bit-field. */
5075 bool last_field_was_bitfield = false;
5076 /* The location at which the next field should be inserted. */
5078 /* T, as a base class. */
5081 /* Keep track of the first non-static data member. */
5082 non_static_data_members = TYPE_FIELDS (t);
5084 /* Start laying out the record. */
5085 rli = start_record_layout (t);
5087 /* Mark all the primary bases in the hierarchy. */
5088 determine_primary_bases (t);
5090 /* Create a pointer to our virtual function table. */
5091 vptr = create_vtable_ptr (t, virtuals_p);
5093 /* The vptr is always the first thing in the class. */
5096 DECL_CHAIN (vptr) = TYPE_FIELDS (t);
5097 TYPE_FIELDS (t) = vptr;
5098 next_field = &DECL_CHAIN (vptr);
5099 place_field (rli, vptr);
5102 next_field = &TYPE_FIELDS (t);
5104 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5105 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
5107 build_base_fields (rli, empty_base_offsets, next_field);
5109 /* Layout the non-static data members. */
5110 for (field = non_static_data_members; field; field = DECL_CHAIN (field))
5115 /* We still pass things that aren't non-static data members to
5116 the back end, in case it wants to do something with them. */
5117 if (TREE_CODE (field) != FIELD_DECL)
5119 place_field (rli, field);
5120 /* If the static data member has incomplete type, keep track
5121 of it so that it can be completed later. (The handling
5122 of pending statics in finish_record_layout is
5123 insufficient; consider:
5126 struct S2 { static S1 s1; };
5128 At this point, finish_record_layout will be called, but
5129 S1 is still incomplete.) */
5130 if (TREE_CODE (field) == VAR_DECL)
5132 maybe_register_incomplete_var (field);
5133 /* The visibility of static data members is determined
5134 at their point of declaration, not their point of
5136 determine_visibility (field);
5141 type = TREE_TYPE (field);
5142 if (type == error_mark_node)
5145 padding = NULL_TREE;
5147 /* If this field is a bit-field whose width is greater than its
5148 type, then there are some special rules for allocating
5150 if (DECL_C_BIT_FIELD (field)
5151 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
5155 bool was_unnamed_p = false;
5156 /* We must allocate the bits as if suitably aligned for the
5157 longest integer type that fits in this many bits. type
5158 of the field. Then, we are supposed to use the left over
5159 bits as additional padding. */
5160 for (itk = itk_char; itk != itk_none; ++itk)
5161 if (integer_types[itk] != NULL_TREE
5162 && (INT_CST_LT (size_int (MAX_FIXED_MODE_SIZE),
5163 TYPE_SIZE (integer_types[itk]))
5164 || INT_CST_LT (DECL_SIZE (field),
5165 TYPE_SIZE (integer_types[itk]))))
5168 /* ITK now indicates a type that is too large for the
5169 field. We have to back up by one to find the largest
5174 integer_type = integer_types[itk];
5175 } while (itk > 0 && integer_type == NULL_TREE);
5177 /* Figure out how much additional padding is required. GCC
5178 3.2 always created a padding field, even if it had zero
5180 if (!abi_version_at_least (2)
5181 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
5183 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
5184 /* In a union, the padding field must have the full width
5185 of the bit-field; all fields start at offset zero. */
5186 padding = DECL_SIZE (field);
5189 if (TREE_CODE (t) == UNION_TYPE)
5190 warning (OPT_Wabi, "size assigned to %qT may not be "
5191 "ABI-compliant and may change in a future "
5194 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
5195 TYPE_SIZE (integer_type));
5198 #ifdef PCC_BITFIELD_TYPE_MATTERS
5199 /* An unnamed bitfield does not normally affect the
5200 alignment of the containing class on a target where
5201 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5202 make any exceptions for unnamed bitfields when the
5203 bitfields are longer than their types. Therefore, we
5204 temporarily give the field a name. */
5205 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
5207 was_unnamed_p = true;
5208 DECL_NAME (field) = make_anon_name ();
5211 DECL_SIZE (field) = TYPE_SIZE (integer_type);
5212 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
5213 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
5214 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5215 empty_base_offsets);
5217 DECL_NAME (field) = NULL_TREE;
5218 /* Now that layout has been performed, set the size of the
5219 field to the size of its declared type; the rest of the
5220 field is effectively invisible. */
5221 DECL_SIZE (field) = TYPE_SIZE (type);
5222 /* We must also reset the DECL_MODE of the field. */
5223 if (abi_version_at_least (2))
5224 DECL_MODE (field) = TYPE_MODE (type);
5226 && DECL_MODE (field) != TYPE_MODE (type))
5227 /* Versions of G++ before G++ 3.4 did not reset the
5230 "the offset of %qD may not be ABI-compliant and may "
5231 "change in a future version of GCC", field);
5234 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5235 empty_base_offsets);
5237 /* Remember the location of any empty classes in FIELD. */
5238 if (abi_version_at_least (2))
5239 record_subobject_offsets (TREE_TYPE (field),
5240 byte_position(field),
5242 /*is_data_member=*/true);
5244 /* If a bit-field does not immediately follow another bit-field,
5245 and yet it starts in the middle of a byte, we have failed to
5246 comply with the ABI. */
5248 && DECL_C_BIT_FIELD (field)
5249 /* The TREE_NO_WARNING flag gets set by Objective-C when
5250 laying out an Objective-C class. The ObjC ABI differs
5251 from the C++ ABI, and so we do not want a warning
5253 && !TREE_NO_WARNING (field)
5254 && !last_field_was_bitfield
5255 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5256 DECL_FIELD_BIT_OFFSET (field),
5257 bitsize_unit_node)))
5258 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5259 "change in a future version of GCC", field);
5261 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5262 offset of the field. */
5264 && !abi_version_at_least (2)
5265 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5266 byte_position (field))
5267 && contains_empty_class_p (TREE_TYPE (field)))
5268 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5269 "classes to be placed at different locations in a "
5270 "future version of GCC", field);
5272 /* The middle end uses the type of expressions to determine the
5273 possible range of expression values. In order to optimize
5274 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5275 must be made aware of the width of "i", via its type.
5277 Because C++ does not have integer types of arbitrary width,
5278 we must (for the purposes of the front end) convert from the
5279 type assigned here to the declared type of the bitfield
5280 whenever a bitfield expression is used as an rvalue.
5281 Similarly, when assigning a value to a bitfield, the value
5282 must be converted to the type given the bitfield here. */
5283 if (DECL_C_BIT_FIELD (field))
5285 unsigned HOST_WIDE_INT width;
5286 tree ftype = TREE_TYPE (field);
5287 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5288 if (width != TYPE_PRECISION (ftype))
5291 = c_build_bitfield_integer_type (width,
5292 TYPE_UNSIGNED (ftype));
5294 = cp_build_qualified_type (TREE_TYPE (field),
5295 cp_type_quals (ftype));
5299 /* If we needed additional padding after this field, add it
5305 padding_field = build_decl (input_location,
5309 DECL_BIT_FIELD (padding_field) = 1;
5310 DECL_SIZE (padding_field) = padding;
5311 DECL_CONTEXT (padding_field) = t;
5312 DECL_ARTIFICIAL (padding_field) = 1;
5313 DECL_IGNORED_P (padding_field) = 1;
5314 layout_nonempty_base_or_field (rli, padding_field,
5316 empty_base_offsets);
5319 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5322 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5324 /* Make sure that we are on a byte boundary so that the size of
5325 the class without virtual bases will always be a round number
5327 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5328 normalize_rli (rli);
5331 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5333 if (!abi_version_at_least (2))
5334 include_empty_classes(rli);
5336 /* Delete all zero-width bit-fields from the list of fields. Now
5337 that the type is laid out they are no longer important. */
5338 remove_zero_width_bit_fields (t);
5340 /* Create the version of T used for virtual bases. We do not use
5341 make_class_type for this version; this is an artificial type. For
5342 a POD type, we just reuse T. */
5343 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5345 base_t = make_node (TREE_CODE (t));
5347 /* Set the size and alignment for the new type. In G++ 3.2, all
5348 empty classes were considered to have size zero when used as
5350 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5352 TYPE_SIZE (base_t) = bitsize_zero_node;
5353 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5354 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5356 "layout of classes derived from empty class %qT "
5357 "may change in a future version of GCC",
5364 /* If the ABI version is not at least two, and the last
5365 field was a bit-field, RLI may not be on a byte
5366 boundary. In particular, rli_size_unit_so_far might
5367 indicate the last complete byte, while rli_size_so_far
5368 indicates the total number of bits used. Therefore,
5369 rli_size_so_far, rather than rli_size_unit_so_far, is
5370 used to compute TYPE_SIZE_UNIT. */
5371 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5372 TYPE_SIZE_UNIT (base_t)
5373 = size_binop (MAX_EXPR,
5375 size_binop (CEIL_DIV_EXPR,
5376 rli_size_so_far (rli),
5377 bitsize_int (BITS_PER_UNIT))),
5380 = size_binop (MAX_EXPR,
5381 rli_size_so_far (rli),
5382 size_binop (MULT_EXPR,
5383 convert (bitsizetype, eoc),
5384 bitsize_int (BITS_PER_UNIT)));
5386 TYPE_ALIGN (base_t) = rli->record_align;
5387 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5389 /* Copy the fields from T. */
5390 next_field = &TYPE_FIELDS (base_t);
5391 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5392 if (TREE_CODE (field) == FIELD_DECL)
5394 *next_field = build_decl (input_location,
5398 DECL_CONTEXT (*next_field) = base_t;
5399 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5400 DECL_FIELD_BIT_OFFSET (*next_field)
5401 = DECL_FIELD_BIT_OFFSET (field);
5402 DECL_SIZE (*next_field) = DECL_SIZE (field);
5403 DECL_MODE (*next_field) = DECL_MODE (field);
5404 next_field = &DECL_CHAIN (*next_field);
5407 /* Record the base version of the type. */
5408 CLASSTYPE_AS_BASE (t) = base_t;
5409 TYPE_CONTEXT (base_t) = t;
5412 CLASSTYPE_AS_BASE (t) = t;
5414 /* Every empty class contains an empty class. */
5415 if (CLASSTYPE_EMPTY_P (t))
5416 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5418 /* Set the TYPE_DECL for this type to contain the right
5419 value for DECL_OFFSET, so that we can use it as part
5420 of a COMPONENT_REF for multiple inheritance. */
5421 layout_decl (TYPE_MAIN_DECL (t), 0);
5423 /* Now fix up any virtual base class types that we left lying
5424 around. We must get these done before we try to lay out the
5425 virtual function table. As a side-effect, this will remove the
5426 base subobject fields. */
5427 layout_virtual_bases (rli, empty_base_offsets);
5429 /* Make sure that empty classes are reflected in RLI at this
5431 include_empty_classes(rli);
5433 /* Make sure not to create any structures with zero size. */
5434 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5436 build_decl (input_location,
5437 FIELD_DECL, NULL_TREE, char_type_node));
5439 /* If this is a non-POD, declaring it packed makes a difference to how it
5440 can be used as a field; don't let finalize_record_size undo it. */
5441 if (TYPE_PACKED (t) && !layout_pod_type_p (t))
5442 rli->packed_maybe_necessary = true;
5444 /* Let the back end lay out the type. */
5445 finish_record_layout (rli, /*free_p=*/true);
5447 /* Warn about bases that can't be talked about due to ambiguity. */
5448 warn_about_ambiguous_bases (t);
5450 /* Now that we're done with layout, give the base fields the real types. */
5451 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5452 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5453 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5456 splay_tree_delete (empty_base_offsets);
5458 if (CLASSTYPE_EMPTY_P (t)
5459 && tree_int_cst_lt (sizeof_biggest_empty_class,
5460 TYPE_SIZE_UNIT (t)))
5461 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5464 /* Determine the "key method" for the class type indicated by TYPE,
5465 and set CLASSTYPE_KEY_METHOD accordingly. */
5468 determine_key_method (tree type)
5472 if (TYPE_FOR_JAVA (type)
5473 || processing_template_decl
5474 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5475 || CLASSTYPE_INTERFACE_KNOWN (type))
5478 /* The key method is the first non-pure virtual function that is not
5479 inline at the point of class definition. On some targets the
5480 key function may not be inline; those targets should not call
5481 this function until the end of the translation unit. */
5482 for (method = TYPE_METHODS (type); method != NULL_TREE;
5483 method = DECL_CHAIN (method))
5484 if (DECL_VINDEX (method) != NULL_TREE
5485 && ! DECL_DECLARED_INLINE_P (method)
5486 && ! DECL_PURE_VIRTUAL_P (method))
5488 CLASSTYPE_KEY_METHOD (type) = method;
5495 /* Perform processing required when the definition of T (a class type)
5499 finish_struct_1 (tree t)
5502 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5503 tree virtuals = NULL_TREE;
5506 if (COMPLETE_TYPE_P (t))
5508 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5509 error ("redefinition of %q#T", t);
5514 /* If this type was previously laid out as a forward reference,
5515 make sure we lay it out again. */
5516 TYPE_SIZE (t) = NULL_TREE;
5517 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5519 /* Make assumptions about the class; we'll reset the flags if
5521 CLASSTYPE_EMPTY_P (t) = 1;
5522 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5523 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5524 CLASSTYPE_LITERAL_P (t) = true;
5526 /* Do end-of-class semantic processing: checking the validity of the
5527 bases and members and add implicitly generated methods. */
5528 check_bases_and_members (t);
5530 /* Find the key method. */
5531 if (TYPE_CONTAINS_VPTR_P (t))
5533 /* The Itanium C++ ABI permits the key method to be chosen when
5534 the class is defined -- even though the key method so
5535 selected may later turn out to be an inline function. On
5536 some systems (such as ARM Symbian OS) the key method cannot
5537 be determined until the end of the translation unit. On such
5538 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5539 will cause the class to be added to KEYED_CLASSES. Then, in
5540 finish_file we will determine the key method. */
5541 if (targetm.cxx.key_method_may_be_inline ())
5542 determine_key_method (t);
5544 /* If a polymorphic class has no key method, we may emit the vtable
5545 in every translation unit where the class definition appears. */
5546 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5547 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5550 /* Layout the class itself. */
5551 layout_class_type (t, &virtuals);
5552 if (CLASSTYPE_AS_BASE (t) != t)
5553 /* We use the base type for trivial assignments, and hence it
5555 compute_record_mode (CLASSTYPE_AS_BASE (t));
5557 virtuals = modify_all_vtables (t, nreverse (virtuals));
5559 /* If necessary, create the primary vtable for this class. */
5560 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5562 /* We must enter these virtuals into the table. */
5563 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5564 build_primary_vtable (NULL_TREE, t);
5565 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5566 /* Here we know enough to change the type of our virtual
5567 function table, but we will wait until later this function. */
5568 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5571 if (TYPE_CONTAINS_VPTR_P (t))
5576 if (BINFO_VTABLE (TYPE_BINFO (t)))
5577 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5578 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5579 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5581 /* Add entries for virtual functions introduced by this class. */
5582 BINFO_VIRTUALS (TYPE_BINFO (t))
5583 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5585 /* Set DECL_VINDEX for all functions declared in this class. */
5586 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5588 fn = TREE_CHAIN (fn),
5589 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5590 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5592 tree fndecl = BV_FN (fn);
5594 if (DECL_THUNK_P (fndecl))
5595 /* A thunk. We should never be calling this entry directly
5596 from this vtable -- we'd use the entry for the non
5597 thunk base function. */
5598 DECL_VINDEX (fndecl) = NULL_TREE;
5599 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5600 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5604 finish_struct_bits (t);
5606 /* Complete the rtl for any static member objects of the type we're
5608 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
5609 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5610 && TREE_TYPE (x) != error_mark_node
5611 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5612 DECL_MODE (x) = TYPE_MODE (t);
5614 /* Done with FIELDS...now decide whether to sort these for
5615 faster lookups later.
5617 We use a small number because most searches fail (succeeding
5618 ultimately as the search bores through the inheritance
5619 hierarchy), and we want this failure to occur quickly. */
5621 n_fields = count_fields (TYPE_FIELDS (t));
5624 struct sorted_fields_type *field_vec = ggc_alloc_sorted_fields_type
5625 (sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5626 field_vec->len = n_fields;
5627 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5628 qsort (field_vec->elts, n_fields, sizeof (tree),
5630 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
5633 /* Complain if one of the field types requires lower visibility. */
5634 constrain_class_visibility (t);
5636 /* Make the rtl for any new vtables we have created, and unmark
5637 the base types we marked. */
5640 /* Build the VTT for T. */
5643 /* This warning does not make sense for Java classes, since they
5644 cannot have destructors. */
5645 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5649 dtor = CLASSTYPE_DESTRUCTORS (t);
5650 if (/* An implicitly declared destructor is always public. And,
5651 if it were virtual, we would have created it by now. */
5653 || (!DECL_VINDEX (dtor)
5654 && (/* public non-virtual */
5655 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5656 || (/* non-public non-virtual with friends */
5657 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5658 && (CLASSTYPE_FRIEND_CLASSES (t)
5659 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5660 warning (OPT_Wnon_virtual_dtor,
5661 "%q#T has virtual functions and accessible"
5662 " non-virtual destructor", t);
5667 if (warn_overloaded_virtual)
5670 /* Class layout, assignment of virtual table slots, etc., is now
5671 complete. Give the back end a chance to tweak the visibility of
5672 the class or perform any other required target modifications. */
5673 targetm.cxx.adjust_class_at_definition (t);
5675 maybe_suppress_debug_info (t);
5677 dump_class_hierarchy (t);
5679 /* Finish debugging output for this type. */
5680 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5683 /* When T was built up, the member declarations were added in reverse
5684 order. Rearrange them to declaration order. */
5687 unreverse_member_declarations (tree t)
5693 /* The following lists are all in reverse order. Put them in
5694 declaration order now. */
5695 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5696 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5698 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5699 reverse order, so we can't just use nreverse. */
5701 for (x = TYPE_FIELDS (t);
5702 x && TREE_CODE (x) != TYPE_DECL;
5705 next = DECL_CHAIN (x);
5706 DECL_CHAIN (x) = prev;
5711 DECL_CHAIN (TYPE_FIELDS (t)) = x;
5713 TYPE_FIELDS (t) = prev;
5718 finish_struct (tree t, tree attributes)
5720 location_t saved_loc = input_location;
5722 /* Now that we've got all the field declarations, reverse everything
5724 unreverse_member_declarations (t);
5726 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5728 /* Nadger the current location so that diagnostics point to the start of
5729 the struct, not the end. */
5730 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5732 if (processing_template_decl)
5736 finish_struct_methods (t);
5737 TYPE_SIZE (t) = bitsize_zero_node;
5738 TYPE_SIZE_UNIT (t) = size_zero_node;
5740 /* We need to emit an error message if this type was used as a parameter
5741 and it is an abstract type, even if it is a template. We construct
5742 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5743 account and we call complete_vars with this type, which will check
5744 the PARM_DECLS. Note that while the type is being defined,
5745 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5746 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5747 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5748 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
5749 if (DECL_PURE_VIRTUAL_P (x))
5750 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5753 /* Remember current #pragma pack value. */
5754 TYPE_PRECISION (t) = maximum_field_alignment;
5757 finish_struct_1 (t);
5759 input_location = saved_loc;
5761 TYPE_BEING_DEFINED (t) = 0;
5763 if (current_class_type)
5766 error ("trying to finish struct, but kicked out due to previous parse errors");
5768 if (processing_template_decl && at_function_scope_p ())
5769 add_stmt (build_min (TAG_DEFN, t));
5774 /* Return the dynamic type of INSTANCE, if known.
5775 Used to determine whether the virtual function table is needed
5778 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5779 of our knowledge of its type. *NONNULL should be initialized
5780 before this function is called. */
5783 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5785 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5787 switch (TREE_CODE (instance))
5790 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5793 return RECUR (TREE_OPERAND (instance, 0));
5796 /* This is a call to a constructor, hence it's never zero. */
5797 if (TREE_HAS_CONSTRUCTOR (instance))
5801 return TREE_TYPE (instance);
5806 /* This is a call to a constructor, hence it's never zero. */
5807 if (TREE_HAS_CONSTRUCTOR (instance))
5811 return TREE_TYPE (instance);
5813 return RECUR (TREE_OPERAND (instance, 0));
5815 case POINTER_PLUS_EXPR:
5818 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5819 return RECUR (TREE_OPERAND (instance, 0));
5820 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5821 /* Propagate nonnull. */
5822 return RECUR (TREE_OPERAND (instance, 0));
5827 return RECUR (TREE_OPERAND (instance, 0));
5830 instance = TREE_OPERAND (instance, 0);
5833 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5834 with a real object -- given &p->f, p can still be null. */
5835 tree t = get_base_address (instance);
5836 /* ??? Probably should check DECL_WEAK here. */
5837 if (t && DECL_P (t))
5840 return RECUR (instance);
5843 /* If this component is really a base class reference, then the field
5844 itself isn't definitive. */
5845 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5846 return RECUR (TREE_OPERAND (instance, 0));
5847 return RECUR (TREE_OPERAND (instance, 1));
5851 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5852 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
5856 return TREE_TYPE (TREE_TYPE (instance));
5858 /* fall through... */
5862 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
5866 return TREE_TYPE (instance);
5868 else if (instance == current_class_ptr)
5873 /* if we're in a ctor or dtor, we know our type. */
5874 if (DECL_LANG_SPECIFIC (current_function_decl)
5875 && (DECL_CONSTRUCTOR_P (current_function_decl)
5876 || DECL_DESTRUCTOR_P (current_function_decl)))
5880 return TREE_TYPE (TREE_TYPE (instance));
5883 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5885 /* We only need one hash table because it is always left empty. */
5888 ht = htab_create (37,
5893 /* Reference variables should be references to objects. */
5897 /* Enter the INSTANCE in a table to prevent recursion; a
5898 variable's initializer may refer to the variable
5900 if (TREE_CODE (instance) == VAR_DECL
5901 && DECL_INITIAL (instance)
5902 && !htab_find (ht, instance))
5907 slot = htab_find_slot (ht, instance, INSERT);
5909 type = RECUR (DECL_INITIAL (instance));
5910 htab_remove_elt (ht, instance);
5923 /* Return nonzero if the dynamic type of INSTANCE is known, and
5924 equivalent to the static type. We also handle the case where
5925 INSTANCE is really a pointer. Return negative if this is a
5926 ctor/dtor. There the dynamic type is known, but this might not be
5927 the most derived base of the original object, and hence virtual
5928 bases may not be layed out according to this type.
5930 Used to determine whether the virtual function table is needed
5933 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5934 of our knowledge of its type. *NONNULL should be initialized
5935 before this function is called. */
5938 resolves_to_fixed_type_p (tree instance, int* nonnull)
5940 tree t = TREE_TYPE (instance);
5942 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5943 if (fixed == NULL_TREE)
5945 if (POINTER_TYPE_P (t))
5947 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5949 return cdtorp ? -1 : 1;
5954 init_class_processing (void)
5956 current_class_depth = 0;
5957 current_class_stack_size = 10;
5959 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5960 local_classes = VEC_alloc (tree, gc, 8);
5961 sizeof_biggest_empty_class = size_zero_node;
5963 ridpointers[(int) RID_PUBLIC] = access_public_node;
5964 ridpointers[(int) RID_PRIVATE] = access_private_node;
5965 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5968 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5971 restore_class_cache (void)
5975 /* We are re-entering the same class we just left, so we don't
5976 have to search the whole inheritance matrix to find all the
5977 decls to bind again. Instead, we install the cached
5978 class_shadowed list and walk through it binding names. */
5979 push_binding_level (previous_class_level);
5980 class_binding_level = previous_class_level;
5981 /* Restore IDENTIFIER_TYPE_VALUE. */
5982 for (type = class_binding_level->type_shadowed;
5984 type = TREE_CHAIN (type))
5985 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5988 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5989 appropriate for TYPE.
5991 So that we may avoid calls to lookup_name, we cache the _TYPE
5992 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5994 For multiple inheritance, we perform a two-pass depth-first search
5995 of the type lattice. */
5998 pushclass (tree type)
6000 class_stack_node_t csn;
6002 type = TYPE_MAIN_VARIANT (type);
6004 /* Make sure there is enough room for the new entry on the stack. */
6005 if (current_class_depth + 1 >= current_class_stack_size)
6007 current_class_stack_size *= 2;
6009 = XRESIZEVEC (struct class_stack_node, current_class_stack,
6010 current_class_stack_size);
6013 /* Insert a new entry on the class stack. */
6014 csn = current_class_stack + current_class_depth;
6015 csn->name = current_class_name;
6016 csn->type = current_class_type;
6017 csn->access = current_access_specifier;
6018 csn->names_used = 0;
6020 current_class_depth++;
6022 /* Now set up the new type. */
6023 current_class_name = TYPE_NAME (type);
6024 if (TREE_CODE (current_class_name) == TYPE_DECL)
6025 current_class_name = DECL_NAME (current_class_name);
6026 current_class_type = type;
6028 /* By default, things in classes are private, while things in
6029 structures or unions are public. */
6030 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
6031 ? access_private_node
6032 : access_public_node);
6034 if (previous_class_level
6035 && type != previous_class_level->this_entity
6036 && current_class_depth == 1)
6038 /* Forcibly remove any old class remnants. */
6039 invalidate_class_lookup_cache ();
6042 if (!previous_class_level
6043 || type != previous_class_level->this_entity
6044 || current_class_depth > 1)
6047 restore_class_cache ();
6050 /* When we exit a toplevel class scope, we save its binding level so
6051 that we can restore it quickly. Here, we've entered some other
6052 class, so we must invalidate our cache. */
6055 invalidate_class_lookup_cache (void)
6057 previous_class_level = NULL;
6060 /* Get out of the current class scope. If we were in a class scope
6061 previously, that is the one popped to. */
6068 current_class_depth--;
6069 current_class_name = current_class_stack[current_class_depth].name;
6070 current_class_type = current_class_stack[current_class_depth].type;
6071 current_access_specifier = current_class_stack[current_class_depth].access;
6072 if (current_class_stack[current_class_depth].names_used)
6073 splay_tree_delete (current_class_stack[current_class_depth].names_used);
6076 /* Mark the top of the class stack as hidden. */
6079 push_class_stack (void)
6081 if (current_class_depth)
6082 ++current_class_stack[current_class_depth - 1].hidden;
6085 /* Mark the top of the class stack as un-hidden. */
6088 pop_class_stack (void)
6090 if (current_class_depth)
6091 --current_class_stack[current_class_depth - 1].hidden;
6094 /* Returns 1 if the class type currently being defined is either T or
6095 a nested type of T. */
6098 currently_open_class (tree t)
6102 if (!CLASS_TYPE_P (t))
6105 t = TYPE_MAIN_VARIANT (t);
6107 /* We start looking from 1 because entry 0 is from global scope,
6109 for (i = current_class_depth; i > 0; --i)
6112 if (i == current_class_depth)
6113 c = current_class_type;
6116 if (current_class_stack[i].hidden)
6118 c = current_class_stack[i].type;
6122 if (same_type_p (c, t))
6128 /* If either current_class_type or one of its enclosing classes are derived
6129 from T, return the appropriate type. Used to determine how we found
6130 something via unqualified lookup. */
6133 currently_open_derived_class (tree t)
6137 /* The bases of a dependent type are unknown. */
6138 if (dependent_type_p (t))
6141 if (!current_class_type)
6144 if (DERIVED_FROM_P (t, current_class_type))
6145 return current_class_type;
6147 for (i = current_class_depth - 1; i > 0; --i)
6149 if (current_class_stack[i].hidden)
6151 if (DERIVED_FROM_P (t, current_class_stack[i].type))
6152 return current_class_stack[i].type;
6158 /* Returns the innermost class type which is not a lambda closure type. */
6161 current_nonlambda_class_type (void)
6165 /* We start looking from 1 because entry 0 is from global scope,
6167 for (i = current_class_depth; i > 0; --i)
6170 if (i == current_class_depth)
6171 c = current_class_type;
6174 if (current_class_stack[i].hidden)
6176 c = current_class_stack[i].type;
6180 if (!LAMBDA_TYPE_P (c))
6186 /* When entering a class scope, all enclosing class scopes' names with
6187 static meaning (static variables, static functions, types and
6188 enumerators) have to be visible. This recursive function calls
6189 pushclass for all enclosing class contexts until global or a local
6190 scope is reached. TYPE is the enclosed class. */
6193 push_nested_class (tree type)
6195 /* A namespace might be passed in error cases, like A::B:C. */
6196 if (type == NULL_TREE
6197 || !CLASS_TYPE_P (type))
6200 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
6205 /* Undoes a push_nested_class call. */
6208 pop_nested_class (void)
6210 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
6213 if (context && CLASS_TYPE_P (context))
6214 pop_nested_class ();
6217 /* Returns the number of extern "LANG" blocks we are nested within. */
6220 current_lang_depth (void)
6222 return VEC_length (tree, current_lang_base);
6225 /* Set global variables CURRENT_LANG_NAME to appropriate value
6226 so that behavior of name-mangling machinery is correct. */
6229 push_lang_context (tree name)
6231 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
6233 if (name == lang_name_cplusplus)
6235 current_lang_name = name;
6237 else if (name == lang_name_java)
6239 current_lang_name = name;
6240 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6241 (See record_builtin_java_type in decl.c.) However, that causes
6242 incorrect debug entries if these types are actually used.
6243 So we re-enable debug output after extern "Java". */
6244 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
6245 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
6246 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
6247 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
6248 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
6249 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
6250 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
6251 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
6253 else if (name == lang_name_c)
6255 current_lang_name = name;
6258 error ("language string %<\"%E\"%> not recognized", name);
6261 /* Get out of the current language scope. */
6264 pop_lang_context (void)
6266 current_lang_name = VEC_pop (tree, current_lang_base);
6269 /* Type instantiation routines. */
6271 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6272 matches the TARGET_TYPE. If there is no satisfactory match, return
6273 error_mark_node, and issue an error & warning messages under
6274 control of FLAGS. Permit pointers to member function if FLAGS
6275 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6276 a template-id, and EXPLICIT_TARGS are the explicitly provided
6279 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6280 is the base path used to reference those member functions. If
6281 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6282 resolved to a member function, access checks will be performed and
6283 errors issued if appropriate. */
6286 resolve_address_of_overloaded_function (tree target_type,
6288 tsubst_flags_t flags,
6290 tree explicit_targs,
6293 /* Here's what the standard says:
6297 If the name is a function template, template argument deduction
6298 is done, and if the argument deduction succeeds, the deduced
6299 arguments are used to generate a single template function, which
6300 is added to the set of overloaded functions considered.
6302 Non-member functions and static member functions match targets of
6303 type "pointer-to-function" or "reference-to-function." Nonstatic
6304 member functions match targets of type "pointer-to-member
6305 function;" the function type of the pointer to member is used to
6306 select the member function from the set of overloaded member
6307 functions. If a nonstatic member function is selected, the
6308 reference to the overloaded function name is required to have the
6309 form of a pointer to member as described in 5.3.1.
6311 If more than one function is selected, any template functions in
6312 the set are eliminated if the set also contains a non-template
6313 function, and any given template function is eliminated if the
6314 set contains a second template function that is more specialized
6315 than the first according to the partial ordering rules 14.5.5.2.
6316 After such eliminations, if any, there shall remain exactly one
6317 selected function. */
6320 /* We store the matches in a TREE_LIST rooted here. The functions
6321 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6322 interoperability with most_specialized_instantiation. */
6323 tree matches = NULL_TREE;
6325 tree target_fn_type;
6327 /* By the time we get here, we should be seeing only real
6328 pointer-to-member types, not the internal POINTER_TYPE to
6329 METHOD_TYPE representation. */
6330 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6331 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6333 gcc_assert (is_overloaded_fn (overload));
6335 /* Check that the TARGET_TYPE is reasonable. */
6336 if (TYPE_PTRFN_P (target_type))
6338 else if (TYPE_PTRMEMFUNC_P (target_type))
6339 /* This is OK, too. */
6341 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6342 /* This is OK, too. This comes from a conversion to reference
6344 target_type = build_reference_type (target_type);
6347 if (flags & tf_error)
6348 error ("cannot resolve overloaded function %qD based on"
6349 " conversion to type %qT",
6350 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6351 return error_mark_node;
6354 /* Non-member functions and static member functions match targets of type
6355 "pointer-to-function" or "reference-to-function." Nonstatic member
6356 functions match targets of type "pointer-to-member-function;" the
6357 function type of the pointer to member is used to select the member
6358 function from the set of overloaded member functions.
6360 So figure out the FUNCTION_TYPE that we want to match against. */
6361 target_fn_type = static_fn_type (target_type);
6363 /* If we can find a non-template function that matches, we can just
6364 use it. There's no point in generating template instantiations
6365 if we're just going to throw them out anyhow. But, of course, we
6366 can only do this when we don't *need* a template function. */
6371 for (fns = overload; fns; fns = OVL_NEXT (fns))
6373 tree fn = OVL_CURRENT (fns);
6375 if (TREE_CODE (fn) == TEMPLATE_DECL)
6376 /* We're not looking for templates just yet. */
6379 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6381 /* We're looking for a non-static member, and this isn't
6382 one, or vice versa. */
6385 /* Ignore functions which haven't been explicitly
6387 if (DECL_ANTICIPATED (fn))
6390 /* See if there's a match. */
6391 if (same_type_p (target_fn_type, static_fn_type (fn)))
6392 matches = tree_cons (fn, NULL_TREE, matches);
6396 /* Now, if we've already got a match (or matches), there's no need
6397 to proceed to the template functions. But, if we don't have a
6398 match we need to look at them, too. */
6401 tree target_arg_types;
6402 tree target_ret_type;
6405 unsigned int nargs, ia;
6408 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6409 target_ret_type = TREE_TYPE (target_fn_type);
6411 nargs = list_length (target_arg_types);
6412 args = XALLOCAVEC (tree, nargs);
6413 for (arg = target_arg_types, ia = 0;
6414 arg != NULL_TREE && arg != void_list_node;
6415 arg = TREE_CHAIN (arg), ++ia)
6416 args[ia] = TREE_VALUE (arg);
6419 for (fns = overload; fns; fns = OVL_NEXT (fns))
6421 tree fn = OVL_CURRENT (fns);
6425 if (TREE_CODE (fn) != TEMPLATE_DECL)
6426 /* We're only looking for templates. */
6429 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6431 /* We're not looking for a non-static member, and this is
6432 one, or vice versa. */
6435 /* Try to do argument deduction. */
6436 targs = make_tree_vec (DECL_NTPARMS (fn));
6437 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6438 target_ret_type, DEDUCE_EXACT,
6440 /* Argument deduction failed. */
6443 /* Instantiate the template. */
6444 instantiation = instantiate_template (fn, targs, flags);
6445 if (instantiation == error_mark_node)
6446 /* Instantiation failed. */
6449 /* See if there's a match. */
6450 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
6451 matches = tree_cons (instantiation, fn, matches);
6454 /* Now, remove all but the most specialized of the matches. */
6457 tree match = most_specialized_instantiation (matches);
6459 if (match != error_mark_node)
6460 matches = tree_cons (TREE_PURPOSE (match),
6466 /* Now we should have exactly one function in MATCHES. */
6467 if (matches == NULL_TREE)
6469 /* There were *no* matches. */
6470 if (flags & tf_error)
6472 error ("no matches converting function %qD to type %q#T",
6473 DECL_NAME (OVL_CURRENT (overload)),
6476 /* print_candidates expects a chain with the functions in
6477 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6478 so why be clever?). */
6479 for (; overload; overload = OVL_NEXT (overload))
6480 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
6483 print_candidates (matches);
6485 return error_mark_node;
6487 else if (TREE_CHAIN (matches))
6489 /* There were too many matches. First check if they're all
6490 the same function. */
6493 fn = TREE_PURPOSE (matches);
6494 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6495 if (!decls_match (fn, TREE_PURPOSE (match)))
6500 if (flags & tf_error)
6502 error ("converting overloaded function %qD to type %q#T is ambiguous",
6503 DECL_NAME (OVL_FUNCTION (overload)),
6506 /* Since print_candidates expects the functions in the
6507 TREE_VALUE slot, we flip them here. */
6508 for (match = matches; match; match = TREE_CHAIN (match))
6509 TREE_VALUE (match) = TREE_PURPOSE (match);
6511 print_candidates (matches);
6514 return error_mark_node;
6518 /* Good, exactly one match. Now, convert it to the correct type. */
6519 fn = TREE_PURPOSE (matches);
6521 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6522 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6524 static int explained;
6526 if (!(flags & tf_error))
6527 return error_mark_node;
6529 permerror (input_location, "assuming pointer to member %qD", fn);
6532 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6537 /* If we're doing overload resolution purely for the purpose of
6538 determining conversion sequences, we should not consider the
6539 function used. If this conversion sequence is selected, the
6540 function will be marked as used at this point. */
6541 if (!(flags & tf_conv))
6543 /* Make =delete work with SFINAE. */
6544 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6545 return error_mark_node;
6550 /* We could not check access to member functions when this
6551 expression was originally created since we did not know at that
6552 time to which function the expression referred. */
6553 if (!(flags & tf_no_access_control)
6554 && DECL_FUNCTION_MEMBER_P (fn))
6556 gcc_assert (access_path);
6557 perform_or_defer_access_check (access_path, fn, fn);
6560 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6561 return cp_build_addr_expr (fn, flags);
6564 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6565 will mark the function as addressed, but here we must do it
6567 cxx_mark_addressable (fn);
6573 /* This function will instantiate the type of the expression given in
6574 RHS to match the type of LHSTYPE. If errors exist, then return
6575 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6576 we complain on errors. If we are not complaining, never modify rhs,
6577 as overload resolution wants to try many possible instantiations, in
6578 the hope that at least one will work.
6580 For non-recursive calls, LHSTYPE should be a function, pointer to
6581 function, or a pointer to member function. */
6584 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6586 tsubst_flags_t flags_in = flags;
6587 tree access_path = NULL_TREE;
6589 flags &= ~tf_ptrmem_ok;
6591 if (lhstype == unknown_type_node)
6593 if (flags & tf_error)
6594 error ("not enough type information");
6595 return error_mark_node;
6598 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6600 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6602 if (flag_ms_extensions
6603 && TYPE_PTRMEMFUNC_P (lhstype)
6604 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6605 /* Microsoft allows `A::f' to be resolved to a
6606 pointer-to-member. */
6610 if (flags & tf_error)
6611 error ("argument of type %qT does not match %qT",
6612 TREE_TYPE (rhs), lhstype);
6613 return error_mark_node;
6617 if (TREE_CODE (rhs) == BASELINK)
6619 access_path = BASELINK_ACCESS_BINFO (rhs);
6620 rhs = BASELINK_FUNCTIONS (rhs);
6623 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6624 deduce any type information. */
6625 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6627 if (flags & tf_error)
6628 error ("not enough type information");
6629 return error_mark_node;
6632 /* There only a few kinds of expressions that may have a type
6633 dependent on overload resolution. */
6634 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6635 || TREE_CODE (rhs) == COMPONENT_REF
6636 || really_overloaded_fn (rhs)
6637 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
6639 /* This should really only be used when attempting to distinguish
6640 what sort of a pointer to function we have. For now, any
6641 arithmetic operation which is not supported on pointers
6642 is rejected as an error. */
6644 switch (TREE_CODE (rhs))
6648 tree member = TREE_OPERAND (rhs, 1);
6650 member = instantiate_type (lhstype, member, flags);
6651 if (member != error_mark_node
6652 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6653 /* Do not lose object's side effects. */
6654 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6655 TREE_OPERAND (rhs, 0), member);
6660 rhs = TREE_OPERAND (rhs, 1);
6661 if (BASELINK_P (rhs))
6662 return instantiate_type (lhstype, rhs, flags_in);
6664 /* This can happen if we are forming a pointer-to-member for a
6666 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6670 case TEMPLATE_ID_EXPR:
6672 tree fns = TREE_OPERAND (rhs, 0);
6673 tree args = TREE_OPERAND (rhs, 1);
6676 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6677 /*template_only=*/true,
6684 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6685 /*template_only=*/false,
6686 /*explicit_targs=*/NULL_TREE,
6691 if (PTRMEM_OK_P (rhs))
6692 flags |= tf_ptrmem_ok;
6694 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6698 return error_mark_node;
6703 return error_mark_node;
6706 /* Return the name of the virtual function pointer field
6707 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6708 this may have to look back through base types to find the
6709 ultimate field name. (For single inheritance, these could
6710 all be the same name. Who knows for multiple inheritance). */
6713 get_vfield_name (tree type)
6715 tree binfo, base_binfo;
6718 for (binfo = TYPE_BINFO (type);
6719 BINFO_N_BASE_BINFOS (binfo);
6722 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6724 if (BINFO_VIRTUAL_P (base_binfo)
6725 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6729 type = BINFO_TYPE (binfo);
6730 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6731 + TYPE_NAME_LENGTH (type) + 2);
6732 sprintf (buf, VFIELD_NAME_FORMAT,
6733 IDENTIFIER_POINTER (constructor_name (type)));
6734 return get_identifier (buf);
6738 print_class_statistics (void)
6740 #ifdef GATHER_STATISTICS
6741 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6742 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6745 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6746 n_vtables, n_vtable_searches);
6747 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6748 n_vtable_entries, n_vtable_elems);
6753 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6754 according to [class]:
6755 The class-name is also inserted
6756 into the scope of the class itself. For purposes of access checking,
6757 the inserted class name is treated as if it were a public member name. */
6760 build_self_reference (void)
6762 tree name = constructor_name (current_class_type);
6763 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6766 DECL_NONLOCAL (value) = 1;
6767 DECL_CONTEXT (value) = current_class_type;
6768 DECL_ARTIFICIAL (value) = 1;
6769 SET_DECL_SELF_REFERENCE_P (value);
6770 set_underlying_type (value);
6772 if (processing_template_decl)
6773 value = push_template_decl (value);
6775 saved_cas = current_access_specifier;
6776 current_access_specifier = access_public_node;
6777 finish_member_declaration (value);
6778 current_access_specifier = saved_cas;
6781 /* Returns 1 if TYPE contains only padding bytes. */
6784 is_empty_class (tree type)
6786 if (type == error_mark_node)
6789 if (! CLASS_TYPE_P (type))
6792 /* In G++ 3.2, whether or not a class was empty was determined by
6793 looking at its size. */
6794 if (abi_version_at_least (2))
6795 return CLASSTYPE_EMPTY_P (type);
6797 return integer_zerop (CLASSTYPE_SIZE (type));
6800 /* Returns true if TYPE contains an empty class. */
6803 contains_empty_class_p (tree type)
6805 if (is_empty_class (type))
6807 if (CLASS_TYPE_P (type))
6814 for (binfo = TYPE_BINFO (type), i = 0;
6815 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6816 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6818 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6819 if (TREE_CODE (field) == FIELD_DECL
6820 && !DECL_ARTIFICIAL (field)
6821 && is_empty_class (TREE_TYPE (field)))
6824 else if (TREE_CODE (type) == ARRAY_TYPE)
6825 return contains_empty_class_p (TREE_TYPE (type));
6829 /* Returns true if TYPE contains no actual data, just various
6830 possible combinations of empty classes and possibly a vptr. */
6833 is_really_empty_class (tree type)
6835 if (CLASS_TYPE_P (type))
6842 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
6843 out, but we'd like to be able to check this before then. */
6844 if (COMPLETE_TYPE_P (type) && is_empty_class (type))
6847 for (binfo = TYPE_BINFO (type), i = 0;
6848 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6849 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
6851 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
6852 if (TREE_CODE (field) == FIELD_DECL
6853 && !DECL_ARTIFICIAL (field)
6854 && !is_really_empty_class (TREE_TYPE (field)))
6858 else if (TREE_CODE (type) == ARRAY_TYPE)
6859 return is_really_empty_class (TREE_TYPE (type));
6863 /* Note that NAME was looked up while the current class was being
6864 defined and that the result of that lookup was DECL. */
6867 maybe_note_name_used_in_class (tree name, tree decl)
6869 splay_tree names_used;
6871 /* If we're not defining a class, there's nothing to do. */
6872 if (!(innermost_scope_kind() == sk_class
6873 && TYPE_BEING_DEFINED (current_class_type)
6874 && !LAMBDA_TYPE_P (current_class_type)))
6877 /* If there's already a binding for this NAME, then we don't have
6878 anything to worry about. */
6879 if (lookup_member (current_class_type, name,
6880 /*protect=*/0, /*want_type=*/false))
6883 if (!current_class_stack[current_class_depth - 1].names_used)
6884 current_class_stack[current_class_depth - 1].names_used
6885 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6886 names_used = current_class_stack[current_class_depth - 1].names_used;
6888 splay_tree_insert (names_used,
6889 (splay_tree_key) name,
6890 (splay_tree_value) decl);
6893 /* Note that NAME was declared (as DECL) in the current class. Check
6894 to see that the declaration is valid. */
6897 note_name_declared_in_class (tree name, tree decl)
6899 splay_tree names_used;
6902 /* Look to see if we ever used this name. */
6904 = current_class_stack[current_class_depth - 1].names_used;
6907 /* The C language allows members to be declared with a type of the same
6908 name, and the C++ standard says this diagnostic is not required. So
6909 allow it in extern "C" blocks unless predantic is specified.
6910 Allow it in all cases if -ms-extensions is specified. */
6911 if ((!pedantic && current_lang_name == lang_name_c)
6912 || flag_ms_extensions)
6914 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6917 /* [basic.scope.class]
6919 A name N used in a class S shall refer to the same declaration
6920 in its context and when re-evaluated in the completed scope of
6922 permerror (input_location, "declaration of %q#D", decl);
6923 permerror (input_location, "changes meaning of %qD from %q+#D",
6924 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6928 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6929 Secondary vtables are merged with primary vtables; this function
6930 will return the VAR_DECL for the primary vtable. */
6933 get_vtbl_decl_for_binfo (tree binfo)
6937 decl = BINFO_VTABLE (binfo);
6938 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
6940 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6941 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6944 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6949 /* Returns the binfo for the primary base of BINFO. If the resulting
6950 BINFO is a virtual base, and it is inherited elsewhere in the
6951 hierarchy, then the returned binfo might not be the primary base of
6952 BINFO in the complete object. Check BINFO_PRIMARY_P or
6953 BINFO_LOST_PRIMARY_P to be sure. */
6956 get_primary_binfo (tree binfo)
6960 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6964 return copied_binfo (primary_base, binfo);
6967 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6970 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6973 fprintf (stream, "%*s", indent, "");
6977 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6978 INDENT should be zero when called from the top level; it is
6979 incremented recursively. IGO indicates the next expected BINFO in
6980 inheritance graph ordering. */
6983 dump_class_hierarchy_r (FILE *stream,
6993 indented = maybe_indent_hierarchy (stream, indent, 0);
6994 fprintf (stream, "%s (0x%lx) ",
6995 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6996 (unsigned long) binfo);
6999 fprintf (stream, "alternative-path\n");
7002 igo = TREE_CHAIN (binfo);
7004 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
7005 tree_low_cst (BINFO_OFFSET (binfo), 0));
7006 if (is_empty_class (BINFO_TYPE (binfo)))
7007 fprintf (stream, " empty");
7008 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
7009 fprintf (stream, " nearly-empty");
7010 if (BINFO_VIRTUAL_P (binfo))
7011 fprintf (stream, " virtual");
7012 fprintf (stream, "\n");
7015 if (BINFO_PRIMARY_P (binfo))
7017 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7018 fprintf (stream, " primary-for %s (0x%lx)",
7019 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
7020 TFF_PLAIN_IDENTIFIER),
7021 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
7023 if (BINFO_LOST_PRIMARY_P (binfo))
7025 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7026 fprintf (stream, " lost-primary");
7029 fprintf (stream, "\n");
7031 if (!(flags & TDF_SLIM))
7035 if (BINFO_SUBVTT_INDEX (binfo))
7037 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7038 fprintf (stream, " subvttidx=%s",
7039 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
7040 TFF_PLAIN_IDENTIFIER));
7042 if (BINFO_VPTR_INDEX (binfo))
7044 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7045 fprintf (stream, " vptridx=%s",
7046 expr_as_string (BINFO_VPTR_INDEX (binfo),
7047 TFF_PLAIN_IDENTIFIER));
7049 if (BINFO_VPTR_FIELD (binfo))
7051 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7052 fprintf (stream, " vbaseoffset=%s",
7053 expr_as_string (BINFO_VPTR_FIELD (binfo),
7054 TFF_PLAIN_IDENTIFIER));
7056 if (BINFO_VTABLE (binfo))
7058 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7059 fprintf (stream, " vptr=%s",
7060 expr_as_string (BINFO_VTABLE (binfo),
7061 TFF_PLAIN_IDENTIFIER));
7065 fprintf (stream, "\n");
7068 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
7069 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
7074 /* Dump the BINFO hierarchy for T. */
7077 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
7079 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7080 fprintf (stream, " size=%lu align=%lu\n",
7081 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
7082 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
7083 fprintf (stream, " base size=%lu base align=%lu\n",
7084 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
7086 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
7088 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
7089 fprintf (stream, "\n");
7092 /* Debug interface to hierarchy dumping. */
7095 debug_class (tree t)
7097 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
7101 dump_class_hierarchy (tree t)
7104 FILE *stream = dump_begin (TDI_class, &flags);
7108 dump_class_hierarchy_1 (stream, flags, t);
7109 dump_end (TDI_class, stream);
7114 dump_array (FILE * stream, tree decl)
7117 unsigned HOST_WIDE_INT ix;
7119 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
7121 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
7123 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
7124 fprintf (stream, " %s entries",
7125 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
7126 TFF_PLAIN_IDENTIFIER));
7127 fprintf (stream, "\n");
7129 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
7131 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
7132 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
7136 dump_vtable (tree t, tree binfo, tree vtable)
7139 FILE *stream = dump_begin (TDI_class, &flags);
7144 if (!(flags & TDF_SLIM))
7146 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
7148 fprintf (stream, "%s for %s",
7149 ctor_vtbl_p ? "Construction vtable" : "Vtable",
7150 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
7153 if (!BINFO_VIRTUAL_P (binfo))
7154 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
7155 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7157 fprintf (stream, "\n");
7158 dump_array (stream, vtable);
7159 fprintf (stream, "\n");
7162 dump_end (TDI_class, stream);
7166 dump_vtt (tree t, tree vtt)
7169 FILE *stream = dump_begin (TDI_class, &flags);
7174 if (!(flags & TDF_SLIM))
7176 fprintf (stream, "VTT for %s\n",
7177 type_as_string (t, TFF_PLAIN_IDENTIFIER));
7178 dump_array (stream, vtt);
7179 fprintf (stream, "\n");
7182 dump_end (TDI_class, stream);
7185 /* Dump a function or thunk and its thunkees. */
7188 dump_thunk (FILE *stream, int indent, tree thunk)
7190 static const char spaces[] = " ";
7191 tree name = DECL_NAME (thunk);
7194 fprintf (stream, "%.*s%p %s %s", indent, spaces,
7196 !DECL_THUNK_P (thunk) ? "function"
7197 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
7198 name ? IDENTIFIER_POINTER (name) : "<unset>");
7199 if (DECL_THUNK_P (thunk))
7201 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
7202 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
7204 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
7205 if (!virtual_adjust)
7207 else if (DECL_THIS_THUNK_P (thunk))
7208 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
7209 tree_low_cst (virtual_adjust, 0));
7211 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
7212 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
7213 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
7214 if (THUNK_ALIAS (thunk))
7215 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
7217 fprintf (stream, "\n");
7218 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
7219 dump_thunk (stream, indent + 2, thunks);
7222 /* Dump the thunks for FN. */
7225 debug_thunks (tree fn)
7227 dump_thunk (stderr, 0, fn);
7230 /* Virtual function table initialization. */
7232 /* Create all the necessary vtables for T and its base classes. */
7235 finish_vtbls (tree t)
7238 VEC(constructor_elt,gc) *v = NULL;
7239 tree vtable = BINFO_VTABLE (TYPE_BINFO (t));
7241 /* We lay out the primary and secondary vtables in one contiguous
7242 vtable. The primary vtable is first, followed by the non-virtual
7243 secondary vtables in inheritance graph order. */
7244 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t),
7247 /* Then come the virtual bases, also in inheritance graph order. */
7248 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
7250 if (!BINFO_VIRTUAL_P (vbase))
7252 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), vtable, t, &v);
7255 if (BINFO_VTABLE (TYPE_BINFO (t)))
7256 initialize_vtable (TYPE_BINFO (t), v);
7259 /* Initialize the vtable for BINFO with the INITS. */
7262 initialize_vtable (tree binfo, VEC(constructor_elt,gc) *inits)
7266 layout_vtable_decl (binfo, VEC_length (constructor_elt, inits));
7267 decl = get_vtbl_decl_for_binfo (binfo);
7268 initialize_artificial_var (decl, inits);
7269 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
7272 /* Build the VTT (virtual table table) for T.
7273 A class requires a VTT if it has virtual bases.
7276 1 - primary virtual pointer for complete object T
7277 2 - secondary VTTs for each direct non-virtual base of T which requires a
7279 3 - secondary virtual pointers for each direct or indirect base of T which
7280 has virtual bases or is reachable via a virtual path from T.
7281 4 - secondary VTTs for each direct or indirect virtual base of T.
7283 Secondary VTTs look like complete object VTTs without part 4. */
7291 VEC(constructor_elt,gc) *inits;
7293 /* Build up the initializers for the VTT. */
7295 index = size_zero_node;
7296 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7298 /* If we didn't need a VTT, we're done. */
7302 /* Figure out the type of the VTT. */
7303 type = build_array_of_n_type (const_ptr_type_node,
7304 VEC_length (constructor_elt, inits));
7306 /* Now, build the VTT object itself. */
7307 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7308 initialize_artificial_var (vtt, inits);
7309 /* Add the VTT to the vtables list. */
7310 DECL_CHAIN (vtt) = DECL_CHAIN (CLASSTYPE_VTABLES (t));
7311 DECL_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7316 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7317 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7318 and CHAIN the vtable pointer for this binfo after construction is
7319 complete. VALUE can also be another BINFO, in which case we recurse. */
7322 binfo_ctor_vtable (tree binfo)
7328 vt = BINFO_VTABLE (binfo);
7329 if (TREE_CODE (vt) == TREE_LIST)
7330 vt = TREE_VALUE (vt);
7331 if (TREE_CODE (vt) == TREE_BINFO)
7340 /* Data for secondary VTT initialization. */
7341 typedef struct secondary_vptr_vtt_init_data_s
7343 /* Is this the primary VTT? */
7346 /* Current index into the VTT. */
7349 /* Vector of initializers built up. */
7350 VEC(constructor_elt,gc) *inits;
7352 /* The type being constructed by this secondary VTT. */
7353 tree type_being_constructed;
7354 } secondary_vptr_vtt_init_data;
7356 /* Recursively build the VTT-initializer for BINFO (which is in the
7357 hierarchy dominated by T). INITS points to the end of the initializer
7358 list to date. INDEX is the VTT index where the next element will be
7359 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7360 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7361 for virtual bases of T. When it is not so, we build the constructor
7362 vtables for the BINFO-in-T variant. */
7365 build_vtt_inits (tree binfo, tree t, VEC(constructor_elt,gc) **inits, tree *index)
7370 secondary_vptr_vtt_init_data data;
7371 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7373 /* We only need VTTs for subobjects with virtual bases. */
7374 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7377 /* We need to use a construction vtable if this is not the primary
7381 build_ctor_vtbl_group (binfo, t);
7383 /* Record the offset in the VTT where this sub-VTT can be found. */
7384 BINFO_SUBVTT_INDEX (binfo) = *index;
7387 /* Add the address of the primary vtable for the complete object. */
7388 init = binfo_ctor_vtable (binfo);
7389 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7392 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7393 BINFO_VPTR_INDEX (binfo) = *index;
7395 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7397 /* Recursively add the secondary VTTs for non-virtual bases. */
7398 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7399 if (!BINFO_VIRTUAL_P (b))
7400 build_vtt_inits (b, t, inits, index);
7402 /* Add secondary virtual pointers for all subobjects of BINFO with
7403 either virtual bases or reachable along a virtual path, except
7404 subobjects that are non-virtual primary bases. */
7405 data.top_level_p = top_level_p;
7406 data.index = *index;
7407 data.inits = *inits;
7408 data.type_being_constructed = BINFO_TYPE (binfo);
7410 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7412 *index = data.index;
7414 /* data.inits might have grown as we added secondary virtual pointers.
7415 Make sure our caller knows about the new vector. */
7416 *inits = data.inits;
7419 /* Add the secondary VTTs for virtual bases in inheritance graph
7421 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7423 if (!BINFO_VIRTUAL_P (b))
7426 build_vtt_inits (b, t, inits, index);
7429 /* Remove the ctor vtables we created. */
7430 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7433 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7434 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7437 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7439 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7441 /* We don't care about bases that don't have vtables. */
7442 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7443 return dfs_skip_bases;
7445 /* We're only interested in proper subobjects of the type being
7447 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7450 /* We're only interested in bases with virtual bases or reachable
7451 via a virtual path from the type being constructed. */
7452 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7453 || binfo_via_virtual (binfo, data->type_being_constructed)))
7454 return dfs_skip_bases;
7456 /* We're not interested in non-virtual primary bases. */
7457 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7460 /* Record the index where this secondary vptr can be found. */
7461 if (data->top_level_p)
7463 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7464 BINFO_VPTR_INDEX (binfo) = data->index;
7466 if (BINFO_VIRTUAL_P (binfo))
7468 /* It's a primary virtual base, and this is not a
7469 construction vtable. Find the base this is primary of in
7470 the inheritance graph, and use that base's vtable
7472 while (BINFO_PRIMARY_P (binfo))
7473 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7477 /* Add the initializer for the secondary vptr itself. */
7478 CONSTRUCTOR_APPEND_ELT (data->inits, NULL_TREE, binfo_ctor_vtable (binfo));
7480 /* Advance the vtt index. */
7481 data->index = size_binop (PLUS_EXPR, data->index,
7482 TYPE_SIZE_UNIT (ptr_type_node));
7487 /* Called from build_vtt_inits via dfs_walk. After building
7488 constructor vtables and generating the sub-vtt from them, we need
7489 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7490 binfo of the base whose sub vtt was generated. */
7493 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7495 tree vtable = BINFO_VTABLE (binfo);
7497 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7498 /* If this class has no vtable, none of its bases do. */
7499 return dfs_skip_bases;
7502 /* This might be a primary base, so have no vtable in this
7506 /* If we scribbled the construction vtable vptr into BINFO, clear it
7508 if (TREE_CODE (vtable) == TREE_LIST
7509 && (TREE_PURPOSE (vtable) == (tree) data))
7510 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7515 /* Build the construction vtable group for BINFO which is in the
7516 hierarchy dominated by T. */
7519 build_ctor_vtbl_group (tree binfo, tree t)
7525 VEC(constructor_elt,gc) *v;
7527 /* See if we've already created this construction vtable group. */
7528 id = mangle_ctor_vtbl_for_type (t, binfo);
7529 if (IDENTIFIER_GLOBAL_VALUE (id))
7532 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7533 /* Build a version of VTBL (with the wrong type) for use in
7534 constructing the addresses of secondary vtables in the
7535 construction vtable group. */
7536 vtbl = build_vtable (t, id, ptr_type_node);
7537 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7540 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7541 binfo, vtbl, t, &v);
7543 /* Add the vtables for each of our virtual bases using the vbase in T
7545 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7547 vbase = TREE_CHAIN (vbase))
7551 if (!BINFO_VIRTUAL_P (vbase))
7553 b = copied_binfo (vbase, binfo);
7555 accumulate_vtbl_inits (b, vbase, binfo, vtbl, t, &v);
7558 /* Figure out the type of the construction vtable. */
7559 type = build_array_of_n_type (vtable_entry_type,
7560 VEC_length (constructor_elt, v));
7562 TREE_TYPE (vtbl) = type;
7563 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7564 layout_decl (vtbl, 0);
7566 /* Initialize the construction vtable. */
7567 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7568 initialize_artificial_var (vtbl, v);
7569 dump_vtable (t, binfo, vtbl);
7572 /* Add the vtbl initializers for BINFO (and its bases other than
7573 non-virtual primaries) to the list of INITS. BINFO is in the
7574 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7575 the constructor the vtbl inits should be accumulated for. (If this
7576 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7577 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7578 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7579 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7580 but are not necessarily the same in terms of layout. */
7583 accumulate_vtbl_inits (tree binfo,
7588 VEC(constructor_elt,gc) **inits)
7592 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7594 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7596 /* If it doesn't have a vptr, we don't do anything. */
7597 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7600 /* If we're building a construction vtable, we're not interested in
7601 subobjects that don't require construction vtables. */
7603 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7604 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7607 /* Build the initializers for the BINFO-in-T vtable. */
7608 dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, vtbl, t, inits);
7610 /* Walk the BINFO and its bases. We walk in preorder so that as we
7611 initialize each vtable we can figure out at what offset the
7612 secondary vtable lies from the primary vtable. We can't use
7613 dfs_walk here because we need to iterate through bases of BINFO
7614 and RTTI_BINFO simultaneously. */
7615 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7617 /* Skip virtual bases. */
7618 if (BINFO_VIRTUAL_P (base_binfo))
7620 accumulate_vtbl_inits (base_binfo,
7621 BINFO_BASE_BINFO (orig_binfo, i),
7622 rtti_binfo, vtbl, t,
7627 /* Called from accumulate_vtbl_inits. Adds the initializers for the
7628 BINFO vtable to L. */
7631 dfs_accumulate_vtbl_inits (tree binfo,
7636 VEC(constructor_elt,gc) **l)
7638 tree vtbl = NULL_TREE;
7639 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7643 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7645 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7646 primary virtual base. If it is not the same primary in
7647 the hierarchy of T, we'll need to generate a ctor vtable
7648 for it, to place at its location in T. If it is the same
7649 primary, we still need a VTT entry for the vtable, but it
7650 should point to the ctor vtable for the base it is a
7651 primary for within the sub-hierarchy of RTTI_BINFO.
7653 There are three possible cases:
7655 1) We are in the same place.
7656 2) We are a primary base within a lost primary virtual base of
7658 3) We are primary to something not a base of RTTI_BINFO. */
7661 tree last = NULL_TREE;
7663 /* First, look through the bases we are primary to for RTTI_BINFO
7664 or a virtual base. */
7666 while (BINFO_PRIMARY_P (b))
7668 b = BINFO_INHERITANCE_CHAIN (b);
7670 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7673 /* If we run out of primary links, keep looking down our
7674 inheritance chain; we might be an indirect primary. */
7675 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7676 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7680 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7681 base B and it is a base of RTTI_BINFO, this is case 2. In
7682 either case, we share our vtable with LAST, i.e. the
7683 derived-most base within B of which we are a primary. */
7685 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7686 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7687 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7688 binfo_ctor_vtable after everything's been set up. */
7691 /* Otherwise, this is case 3 and we get our own. */
7693 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7696 n_inits = VEC_length (constructor_elt, *l);
7703 /* Add the initializer for this vtable. */
7704 build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7705 &non_fn_entries, l);
7707 /* Figure out the position to which the VPTR should point. */
7708 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, orig_vtbl);
7709 index = size_binop (PLUS_EXPR,
7710 size_int (non_fn_entries),
7711 size_int (n_inits));
7712 index = size_binop (MULT_EXPR,
7713 TYPE_SIZE_UNIT (vtable_entry_type),
7715 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7719 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7720 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7721 straighten this out. */
7722 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7723 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7724 /* Throw away any unneeded intializers. */
7725 VEC_truncate (constructor_elt, *l, n_inits);
7727 /* For an ordinary vtable, set BINFO_VTABLE. */
7728 BINFO_VTABLE (binfo) = vtbl;
7731 static GTY(()) tree abort_fndecl_addr;
7733 /* Construct the initializer for BINFO's virtual function table. BINFO
7734 is part of the hierarchy dominated by T. If we're building a
7735 construction vtable, the ORIG_BINFO is the binfo we should use to
7736 find the actual function pointers to put in the vtable - but they
7737 can be overridden on the path to most-derived in the graph that
7738 ORIG_BINFO belongs. Otherwise,
7739 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7740 BINFO that should be indicated by the RTTI information in the
7741 vtable; it will be a base class of T, rather than T itself, if we
7742 are building a construction vtable.
7744 The value returned is a TREE_LIST suitable for wrapping in a
7745 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7746 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7747 number of non-function entries in the vtable.
7749 It might seem that this function should never be called with a
7750 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7751 base is always subsumed by a derived class vtable. However, when
7752 we are building construction vtables, we do build vtables for
7753 primary bases; we need these while the primary base is being
7757 build_vtbl_initializer (tree binfo,
7761 int* non_fn_entries_p,
7762 VEC(constructor_elt,gc) **inits)
7768 VEC(tree,gc) *vbases;
7771 /* Initialize VID. */
7772 memset (&vid, 0, sizeof (vid));
7775 vid.rtti_binfo = rtti_binfo;
7776 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7777 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7778 vid.generate_vcall_entries = true;
7779 /* The first vbase or vcall offset is at index -3 in the vtable. */
7780 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7782 /* Add entries to the vtable for RTTI. */
7783 build_rtti_vtbl_entries (binfo, &vid);
7785 /* Create an array for keeping track of the functions we've
7786 processed. When we see multiple functions with the same
7787 signature, we share the vcall offsets. */
7788 vid.fns = VEC_alloc (tree, gc, 32);
7789 /* Add the vcall and vbase offset entries. */
7790 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7792 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7793 build_vbase_offset_vtbl_entries. */
7794 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7795 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7796 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7798 /* If the target requires padding between data entries, add that now. */
7799 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7801 int n_entries = VEC_length (constructor_elt, vid.inits);
7803 VEC_safe_grow (constructor_elt, gc, vid.inits,
7804 TARGET_VTABLE_DATA_ENTRY_DISTANCE * n_entries);
7806 /* Move data entries into their new positions and add padding
7807 after the new positions. Iterate backwards so we don't
7808 overwrite entries that we would need to process later. */
7809 for (ix = n_entries - 1;
7810 VEC_iterate (constructor_elt, vid.inits, ix, e);
7814 int new_position = (TARGET_VTABLE_DATA_ENTRY_DISTANCE * ix
7815 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE - 1));
7817 VEC_replace (constructor_elt, vid.inits, new_position, e);
7819 for (j = 1; j < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++j)
7821 constructor_elt *f = VEC_index (constructor_elt, vid.inits,
7823 f->index = NULL_TREE;
7824 f->value = build1 (NOP_EXPR, vtable_entry_type,
7830 if (non_fn_entries_p)
7831 *non_fn_entries_p = VEC_length (constructor_elt, vid.inits);
7833 /* The initializers for virtual functions were built up in reverse
7834 order. Straighten them out and add them to the running list in one
7836 jx = VEC_length (constructor_elt, *inits);
7837 VEC_safe_grow (constructor_elt, gc, *inits,
7838 (jx + VEC_length (constructor_elt, vid.inits)));
7840 for (ix = VEC_length (constructor_elt, vid.inits) - 1;
7841 VEC_iterate (constructor_elt, vid.inits, ix, e);
7843 VEC_replace (constructor_elt, *inits, jx, e);
7845 /* Go through all the ordinary virtual functions, building up
7847 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7851 tree fn, fn_original;
7852 tree init = NULL_TREE;
7856 if (DECL_THUNK_P (fn))
7858 if (!DECL_NAME (fn))
7860 if (THUNK_ALIAS (fn))
7862 fn = THUNK_ALIAS (fn);
7865 fn_original = THUNK_TARGET (fn);
7868 /* If the only definition of this function signature along our
7869 primary base chain is from a lost primary, this vtable slot will
7870 never be used, so just zero it out. This is important to avoid
7871 requiring extra thunks which cannot be generated with the function.
7873 We first check this in update_vtable_entry_for_fn, so we handle
7874 restored primary bases properly; we also need to do it here so we
7875 zero out unused slots in ctor vtables, rather than filling them
7876 with erroneous values (though harmless, apart from relocation
7878 if (BV_LOST_PRIMARY (v))
7879 init = size_zero_node;
7883 /* Pull the offset for `this', and the function to call, out of
7885 delta = BV_DELTA (v);
7886 vcall_index = BV_VCALL_INDEX (v);
7888 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7889 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7891 /* You can't call an abstract virtual function; it's abstract.
7892 So, we replace these functions with __pure_virtual. */
7893 if (DECL_PURE_VIRTUAL_P (fn_original))
7896 if (!TARGET_VTABLE_USES_DESCRIPTORS)
7898 if (abort_fndecl_addr == NULL)
7900 = fold_convert (vfunc_ptr_type_node,
7901 build_fold_addr_expr (fn));
7902 init = abort_fndecl_addr;
7907 if (!integer_zerop (delta) || vcall_index)
7909 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7910 if (!DECL_NAME (fn))
7913 /* Take the address of the function, considering it to be of an
7914 appropriate generic type. */
7915 if (!TARGET_VTABLE_USES_DESCRIPTORS)
7916 init = fold_convert (vfunc_ptr_type_node,
7917 build_fold_addr_expr (fn));
7921 /* And add it to the chain of initializers. */
7922 if (TARGET_VTABLE_USES_DESCRIPTORS)
7925 if (init == size_zero_node)
7926 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7927 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7929 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7931 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7932 fn, build_int_cst (NULL_TREE, i));
7933 TREE_CONSTANT (fdesc) = 1;
7935 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, fdesc);
7939 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7943 /* Adds to vid->inits the initializers for the vbase and vcall
7944 offsets in BINFO, which is in the hierarchy dominated by T. */
7947 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7951 /* If this is a derived class, we must first create entries
7952 corresponding to the primary base class. */
7953 b = get_primary_binfo (binfo);
7955 build_vcall_and_vbase_vtbl_entries (b, vid);
7957 /* Add the vbase entries for this base. */
7958 build_vbase_offset_vtbl_entries (binfo, vid);
7959 /* Add the vcall entries for this base. */
7960 build_vcall_offset_vtbl_entries (binfo, vid);
7963 /* Returns the initializers for the vbase offset entries in the vtable
7964 for BINFO (which is part of the class hierarchy dominated by T), in
7965 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7966 where the next vbase offset will go. */
7969 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7973 tree non_primary_binfo;
7975 /* If there are no virtual baseclasses, then there is nothing to
7977 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7982 /* We might be a primary base class. Go up the inheritance hierarchy
7983 until we find the most derived class of which we are a primary base:
7984 it is the offset of that which we need to use. */
7985 non_primary_binfo = binfo;
7986 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7990 /* If we have reached a virtual base, then it must be a primary
7991 base (possibly multi-level) of vid->binfo, or we wouldn't
7992 have called build_vcall_and_vbase_vtbl_entries for it. But it
7993 might be a lost primary, so just skip down to vid->binfo. */
7994 if (BINFO_VIRTUAL_P (non_primary_binfo))
7996 non_primary_binfo = vid->binfo;
8000 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8001 if (get_primary_binfo (b) != non_primary_binfo)
8003 non_primary_binfo = b;
8006 /* Go through the virtual bases, adding the offsets. */
8007 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
8009 vbase = TREE_CHAIN (vbase))
8014 if (!BINFO_VIRTUAL_P (vbase))
8017 /* Find the instance of this virtual base in the complete
8019 b = copied_binfo (vbase, binfo);
8021 /* If we've already got an offset for this virtual base, we
8022 don't need another one. */
8023 if (BINFO_VTABLE_PATH_MARKED (b))
8025 BINFO_VTABLE_PATH_MARKED (b) = 1;
8027 /* Figure out where we can find this vbase offset. */
8028 delta = size_binop (MULT_EXPR,
8031 TYPE_SIZE_UNIT (vtable_entry_type)));
8032 if (vid->primary_vtbl_p)
8033 BINFO_VPTR_FIELD (b) = delta;
8035 if (binfo != TYPE_BINFO (t))
8036 /* The vbase offset had better be the same. */
8037 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
8039 /* The next vbase will come at a more negative offset. */
8040 vid->index = size_binop (MINUS_EXPR, vid->index,
8041 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8043 /* The initializer is the delta from BINFO to this virtual base.
8044 The vbase offsets go in reverse inheritance-graph order, and
8045 we are walking in inheritance graph order so these end up in
8047 delta = size_diffop_loc (input_location,
8048 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
8050 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE,
8051 fold_build1_loc (input_location, NOP_EXPR,
8052 vtable_entry_type, delta));
8056 /* Adds the initializers for the vcall offset entries in the vtable
8057 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
8061 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8063 /* We only need these entries if this base is a virtual base. We
8064 compute the indices -- but do not add to the vtable -- when
8065 building the main vtable for a class. */
8066 if (binfo == TYPE_BINFO (vid->derived)
8067 || (BINFO_VIRTUAL_P (binfo)
8068 /* If BINFO is RTTI_BINFO, then (since BINFO does not
8069 correspond to VID->DERIVED), we are building a primary
8070 construction virtual table. Since this is a primary
8071 virtual table, we do not need the vcall offsets for
8073 && binfo != vid->rtti_binfo))
8075 /* We need a vcall offset for each of the virtual functions in this
8076 vtable. For example:
8078 class A { virtual void f (); };
8079 class B1 : virtual public A { virtual void f (); };
8080 class B2 : virtual public A { virtual void f (); };
8081 class C: public B1, public B2 { virtual void f (); };
8083 A C object has a primary base of B1, which has a primary base of A. A
8084 C also has a secondary base of B2, which no longer has a primary base
8085 of A. So the B2-in-C construction vtable needs a secondary vtable for
8086 A, which will adjust the A* to a B2* to call f. We have no way of
8087 knowing what (or even whether) this offset will be when we define B2,
8088 so we store this "vcall offset" in the A sub-vtable and look it up in
8089 a "virtual thunk" for B2::f.
8091 We need entries for all the functions in our primary vtable and
8092 in our non-virtual bases' secondary vtables. */
8094 /* If we are just computing the vcall indices -- but do not need
8095 the actual entries -- not that. */
8096 if (!BINFO_VIRTUAL_P (binfo))
8097 vid->generate_vcall_entries = false;
8098 /* Now, walk through the non-virtual bases, adding vcall offsets. */
8099 add_vcall_offset_vtbl_entries_r (binfo, vid);
8103 /* Build vcall offsets, starting with those for BINFO. */
8106 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
8112 /* Don't walk into virtual bases -- except, of course, for the
8113 virtual base for which we are building vcall offsets. Any
8114 primary virtual base will have already had its offsets generated
8115 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8116 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
8119 /* If BINFO has a primary base, process it first. */
8120 primary_binfo = get_primary_binfo (binfo);
8122 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
8124 /* Add BINFO itself to the list. */
8125 add_vcall_offset_vtbl_entries_1 (binfo, vid);
8127 /* Scan the non-primary bases of BINFO. */
8128 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8129 if (base_binfo != primary_binfo)
8130 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
8133 /* Called from build_vcall_offset_vtbl_entries_r. */
8136 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
8138 /* Make entries for the rest of the virtuals. */
8139 if (abi_version_at_least (2))
8143 /* The ABI requires that the methods be processed in declaration
8144 order. G++ 3.2 used the order in the vtable. */
8145 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
8147 orig_fn = DECL_CHAIN (orig_fn))
8148 if (DECL_VINDEX (orig_fn))
8149 add_vcall_offset (orig_fn, binfo, vid);
8153 tree derived_virtuals;
8156 /* If BINFO is a primary base, the most derived class which has
8157 BINFO as a primary base; otherwise, just BINFO. */
8158 tree non_primary_binfo;
8160 /* We might be a primary base class. Go up the inheritance hierarchy
8161 until we find the most derived class of which we are a primary base:
8162 it is the BINFO_VIRTUALS there that we need to consider. */
8163 non_primary_binfo = binfo;
8164 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8168 /* If we have reached a virtual base, then it must be vid->vbase,
8169 because we ignore other virtual bases in
8170 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8171 base (possibly multi-level) of vid->binfo, or we wouldn't
8172 have called build_vcall_and_vbase_vtbl_entries for it. But it
8173 might be a lost primary, so just skip down to vid->binfo. */
8174 if (BINFO_VIRTUAL_P (non_primary_binfo))
8176 gcc_assert (non_primary_binfo == vid->vbase);
8177 non_primary_binfo = vid->binfo;
8181 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8182 if (get_primary_binfo (b) != non_primary_binfo)
8184 non_primary_binfo = b;
8187 if (vid->ctor_vtbl_p)
8188 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8189 where rtti_binfo is the most derived type. */
8191 = original_binfo (non_primary_binfo, vid->rtti_binfo);
8193 for (base_virtuals = BINFO_VIRTUALS (binfo),
8194 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
8195 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
8197 base_virtuals = TREE_CHAIN (base_virtuals),
8198 derived_virtuals = TREE_CHAIN (derived_virtuals),
8199 orig_virtuals = TREE_CHAIN (orig_virtuals))
8203 /* Find the declaration that originally caused this function to
8204 be present in BINFO_TYPE (binfo). */
8205 orig_fn = BV_FN (orig_virtuals);
8207 /* When processing BINFO, we only want to generate vcall slots for
8208 function slots introduced in BINFO. So don't try to generate
8209 one if the function isn't even defined in BINFO. */
8210 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
8213 add_vcall_offset (orig_fn, binfo, vid);
8218 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8221 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
8227 /* If there is already an entry for a function with the same
8228 signature as FN, then we do not need a second vcall offset.
8229 Check the list of functions already present in the derived
8231 FOR_EACH_VEC_ELT (tree, vid->fns, i, derived_entry)
8233 if (same_signature_p (derived_entry, orig_fn)
8234 /* We only use one vcall offset for virtual destructors,
8235 even though there are two virtual table entries. */
8236 || (DECL_DESTRUCTOR_P (derived_entry)
8237 && DECL_DESTRUCTOR_P (orig_fn)))
8241 /* If we are building these vcall offsets as part of building
8242 the vtable for the most derived class, remember the vcall
8244 if (vid->binfo == TYPE_BINFO (vid->derived))
8246 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
8247 CLASSTYPE_VCALL_INDICES (vid->derived),
8249 elt->purpose = orig_fn;
8250 elt->value = vid->index;
8253 /* The next vcall offset will be found at a more negative
8255 vid->index = size_binop (MINUS_EXPR, vid->index,
8256 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8258 /* Keep track of this function. */
8259 VEC_safe_push (tree, gc, vid->fns, orig_fn);
8261 if (vid->generate_vcall_entries)
8266 /* Find the overriding function. */
8267 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8268 if (fn == error_mark_node)
8269 vcall_offset = build_zero_cst (vtable_entry_type);
8272 base = TREE_VALUE (fn);
8274 /* The vbase we're working on is a primary base of
8275 vid->binfo. But it might be a lost primary, so its
8276 BINFO_OFFSET might be wrong, so we just use the
8277 BINFO_OFFSET from vid->binfo. */
8278 vcall_offset = size_diffop_loc (input_location,
8279 BINFO_OFFSET (base),
8280 BINFO_OFFSET (vid->binfo));
8281 vcall_offset = fold_build1_loc (input_location,
8282 NOP_EXPR, vtable_entry_type,
8285 /* Add the initializer to the vtable. */
8286 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, vcall_offset);
8290 /* Return vtbl initializers for the RTTI entries corresponding to the
8291 BINFO's vtable. The RTTI entries should indicate the object given
8292 by VID->rtti_binfo. */
8295 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8303 t = BINFO_TYPE (vid->rtti_binfo);
8305 /* To find the complete object, we will first convert to our most
8306 primary base, and then add the offset in the vtbl to that value. */
8308 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8309 && !BINFO_LOST_PRIMARY_P (b))
8313 primary_base = get_primary_binfo (b);
8314 gcc_assert (BINFO_PRIMARY_P (primary_base)
8315 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8318 offset = size_diffop_loc (input_location,
8319 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8321 /* The second entry is the address of the typeinfo object. */
8323 decl = build_address (get_tinfo_decl (t));
8325 decl = integer_zero_node;
8327 /* Convert the declaration to a type that can be stored in the
8329 init = build_nop (vfunc_ptr_type_node, decl);
8330 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8332 /* Add the offset-to-top entry. It comes earlier in the vtable than
8333 the typeinfo entry. Convert the offset to look like a
8334 function pointer, so that we can put it in the vtable. */
8335 init = build_nop (vfunc_ptr_type_node, offset);
8336 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8339 /* Fold a OBJ_TYPE_REF expression to the address of a function.
8340 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
8343 cp_fold_obj_type_ref (tree ref, tree known_type)
8345 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
8346 HOST_WIDE_INT i = 0;
8347 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
8352 i += (TARGET_VTABLE_USES_DESCRIPTORS
8353 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
8359 #ifdef ENABLE_CHECKING
8360 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
8361 DECL_VINDEX (fndecl)));
8364 cgraph_node (fndecl)->local.vtable_method = true;
8366 return build_address (fndecl);
8369 #include "gt-cp-class.h"