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 location_t loc = input_location;
2801 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2804 /* detect invalid field size. */
2805 input_location = DECL_SOURCE_LOCATION (field);
2806 w = cxx_constant_value (w);
2807 input_location = loc;
2809 if (TREE_CODE (w) != INTEGER_CST)
2811 error ("bit-field %q+D width not an integer constant", field);
2812 w = error_mark_node;
2814 else if (tree_int_cst_sgn (w) < 0)
2816 error ("negative width in bit-field %q+D", field);
2817 w = error_mark_node;
2819 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2821 error ("zero width for bit-field %q+D", field);
2822 w = error_mark_node;
2824 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2825 && TREE_CODE (type) != ENUMERAL_TYPE
2826 && TREE_CODE (type) != BOOLEAN_TYPE)
2827 warning (0, "width of %q+D exceeds its type", field);
2828 else if (TREE_CODE (type) == ENUMERAL_TYPE
2829 && (0 > (compare_tree_int
2830 (w, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type))))))
2831 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2834 if (w != error_mark_node)
2836 DECL_SIZE (field) = convert (bitsizetype, w);
2837 DECL_BIT_FIELD (field) = 1;
2842 /* Non-bit-fields are aligned for their type. */
2843 DECL_BIT_FIELD (field) = 0;
2844 CLEAR_DECL_C_BIT_FIELD (field);
2849 /* FIELD is a non bit-field. We are finishing the processing for its
2850 enclosing type T. Issue any appropriate messages and set appropriate
2854 check_field_decl (tree field,
2856 int* cant_have_const_ctor,
2857 int* no_const_asn_ref,
2858 int* any_default_members)
2860 tree type = strip_array_types (TREE_TYPE (field));
2862 /* In C++98 an anonymous union cannot contain any fields which would change
2863 the settings of CANT_HAVE_CONST_CTOR and friends. */
2864 if (ANON_UNION_TYPE_P (type) && cxx_dialect < cxx0x)
2866 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2867 structs. So, we recurse through their fields here. */
2868 else if (ANON_AGGR_TYPE_P (type))
2872 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2873 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2874 check_field_decl (fields, t, cant_have_const_ctor,
2875 no_const_asn_ref, any_default_members);
2877 /* Check members with class type for constructors, destructors,
2879 else if (CLASS_TYPE_P (type))
2881 /* Never let anything with uninheritable virtuals
2882 make it through without complaint. */
2883 abstract_virtuals_error (field, type);
2885 if (TREE_CODE (t) == UNION_TYPE && cxx_dialect < cxx0x)
2888 int oldcount = errorcount;
2889 if (TYPE_NEEDS_CONSTRUCTING (type))
2890 error ("member %q+#D with constructor not allowed in union",
2892 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2893 error ("member %q+#D with destructor not allowed in union", field);
2894 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
2895 error ("member %q+#D with copy assignment operator not allowed in union",
2897 if (!warned && errorcount > oldcount)
2899 inform (DECL_SOURCE_LOCATION (field), "unrestricted unions "
2900 "only available with -std=c++0x or -std=gnu++0x");
2906 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2907 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2908 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2909 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
2910 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type)
2911 || !TYPE_HAS_COPY_ASSIGN (type));
2912 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type)
2913 || !TYPE_HAS_COPY_CTOR (type));
2914 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type);
2915 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type);
2916 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type)
2917 || TYPE_HAS_COMPLEX_DFLT (type));
2920 if (TYPE_HAS_COPY_CTOR (type)
2921 && !TYPE_HAS_CONST_COPY_CTOR (type))
2922 *cant_have_const_ctor = 1;
2924 if (TYPE_HAS_COPY_ASSIGN (type)
2925 && !TYPE_HAS_CONST_COPY_ASSIGN (type))
2926 *no_const_asn_ref = 1;
2928 if (DECL_INITIAL (field) != NULL_TREE)
2930 /* `build_class_init_list' does not recognize
2932 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2933 error ("multiple fields in union %qT initialized", t);
2934 *any_default_members = 1;
2938 /* Check the data members (both static and non-static), class-scoped
2939 typedefs, etc., appearing in the declaration of T. Issue
2940 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2941 declaration order) of access declarations; each TREE_VALUE in this
2942 list is a USING_DECL.
2944 In addition, set the following flags:
2947 The class is empty, i.e., contains no non-static data members.
2949 CANT_HAVE_CONST_CTOR_P
2950 This class cannot have an implicitly generated copy constructor
2951 taking a const reference.
2953 CANT_HAVE_CONST_ASN_REF
2954 This class cannot have an implicitly generated assignment
2955 operator taking a const reference.
2957 All of these flags should be initialized before calling this
2960 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2961 fields can be added by adding to this chain. */
2964 check_field_decls (tree t, tree *access_decls,
2965 int *cant_have_const_ctor_p,
2966 int *no_const_asn_ref_p)
2971 int any_default_members;
2973 int field_access = -1;
2975 /* Assume there are no access declarations. */
2976 *access_decls = NULL_TREE;
2977 /* Assume this class has no pointer members. */
2978 has_pointers = false;
2979 /* Assume none of the members of this class have default
2981 any_default_members = 0;
2983 for (field = &TYPE_FIELDS (t); *field; field = next)
2986 tree type = TREE_TYPE (x);
2987 int this_field_access;
2989 next = &DECL_CHAIN (x);
2991 if (TREE_CODE (x) == USING_DECL)
2993 /* Prune the access declaration from the list of fields. */
2994 *field = DECL_CHAIN (x);
2996 /* Save the access declarations for our caller. */
2997 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2999 /* Since we've reset *FIELD there's no reason to skip to the
3005 if (TREE_CODE (x) == TYPE_DECL
3006 || TREE_CODE (x) == TEMPLATE_DECL)
3009 /* If we've gotten this far, it's a data member, possibly static,
3010 or an enumerator. */
3011 DECL_CONTEXT (x) = t;
3013 /* When this goes into scope, it will be a non-local reference. */
3014 DECL_NONLOCAL (x) = 1;
3016 if (TREE_CODE (t) == UNION_TYPE)
3020 If a union contains a static data member, or a member of
3021 reference type, the program is ill-formed. */
3022 if (TREE_CODE (x) == VAR_DECL)
3024 error ("%q+D may not be static because it is a member of a union", x);
3027 if (TREE_CODE (type) == REFERENCE_TYPE)
3029 error ("%q+D may not have reference type %qT because"
3030 " it is a member of a union",
3036 /* Perform error checking that did not get done in
3038 if (TREE_CODE (type) == FUNCTION_TYPE)
3040 error ("field %q+D invalidly declared function type", x);
3041 type = build_pointer_type (type);
3042 TREE_TYPE (x) = type;
3044 else if (TREE_CODE (type) == METHOD_TYPE)
3046 error ("field %q+D invalidly declared method type", x);
3047 type = build_pointer_type (type);
3048 TREE_TYPE (x) = type;
3051 if (type == error_mark_node)
3054 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
3057 /* Now it can only be a FIELD_DECL. */
3059 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3060 CLASSTYPE_NON_AGGREGATE (t) = 1;
3062 /* If at least one non-static data member is non-literal, the whole
3063 class becomes non-literal. */
3064 if (!literal_type_p (type))
3065 CLASSTYPE_LITERAL_P (t) = false;
3067 /* A standard-layout class is a class that:
3069 has the same access control (Clause 11) for all non-static data members,
3071 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3072 if (field_access == -1)
3073 field_access = this_field_access;
3074 else if (this_field_access != field_access)
3075 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3077 /* If this is of reference type, check if it needs an init. */
3078 if (TREE_CODE (type) == REFERENCE_TYPE)
3080 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3081 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3082 if (DECL_INITIAL (x) == NULL_TREE)
3083 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3085 /* ARM $12.6.2: [A member initializer list] (or, for an
3086 aggregate, initialization by a brace-enclosed list) is the
3087 only way to initialize nonstatic const and reference
3089 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3090 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3093 type = strip_array_types (type);
3095 if (TYPE_PACKED (t))
3097 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3101 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3105 else if (DECL_C_BIT_FIELD (x)
3106 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3107 DECL_PACKED (x) = 1;
3110 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3111 /* We don't treat zero-width bitfields as making a class
3116 /* The class is non-empty. */
3117 CLASSTYPE_EMPTY_P (t) = 0;
3118 /* The class is not even nearly empty. */
3119 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3120 /* If one of the data members contains an empty class,
3122 if (CLASS_TYPE_P (type)
3123 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3124 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3127 /* This is used by -Weffc++ (see below). Warn only for pointers
3128 to members which might hold dynamic memory. So do not warn
3129 for pointers to functions or pointers to members. */
3130 if (TYPE_PTR_P (type)
3131 && !TYPE_PTRFN_P (type)
3132 && !TYPE_PTR_TO_MEMBER_P (type))
3133 has_pointers = true;
3135 if (CLASS_TYPE_P (type))
3137 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3138 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3139 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3140 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3143 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3144 CLASSTYPE_HAS_MUTABLE (t) = 1;
3146 if (! layout_pod_type_p (type))
3147 /* DR 148 now allows pointers to members (which are POD themselves),
3148 to be allowed in POD structs. */
3149 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3151 if (!std_layout_type_p (type))
3152 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3154 if (! zero_init_p (type))
3155 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3157 /* We set DECL_C_BIT_FIELD in grokbitfield.
3158 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3159 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3160 check_field_decl (x, t,
3161 cant_have_const_ctor_p,
3163 &any_default_members);
3165 /* If any field is const, the structure type is pseudo-const. */
3166 if (CP_TYPE_CONST_P (type))
3168 C_TYPE_FIELDS_READONLY (t) = 1;
3169 if (DECL_INITIAL (x) == NULL_TREE)
3170 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3172 /* ARM $12.6.2: [A member initializer list] (or, for an
3173 aggregate, initialization by a brace-enclosed list) is the
3174 only way to initialize nonstatic const and reference
3176 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3177 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3179 /* A field that is pseudo-const makes the structure likewise. */
3180 else if (CLASS_TYPE_P (type))
3182 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3183 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3184 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3185 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3188 /* Core issue 80: A nonstatic data member is required to have a
3189 different name from the class iff the class has a
3190 user-declared constructor. */
3191 if (constructor_name_p (DECL_NAME (x), t)
3192 && TYPE_HAS_USER_CONSTRUCTOR (t))
3193 permerror (input_location, "field %q+#D with same name as class", x);
3196 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3197 it should also define a copy constructor and an assignment operator to
3198 implement the correct copy semantic (deep vs shallow, etc.). As it is
3199 not feasible to check whether the constructors do allocate dynamic memory
3200 and store it within members, we approximate the warning like this:
3202 -- Warn only if there are members which are pointers
3203 -- Warn only if there is a non-trivial constructor (otherwise,
3204 there cannot be memory allocated).
3205 -- Warn only if there is a non-trivial destructor. We assume that the
3206 user at least implemented the cleanup correctly, and a destructor
3207 is needed to free dynamic memory.
3209 This seems enough for practical purposes. */
3212 && TYPE_HAS_USER_CONSTRUCTOR (t)
3213 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3214 && !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
3216 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3218 if (! TYPE_HAS_COPY_CTOR (t))
3220 warning (OPT_Weffc__,
3221 " but does not override %<%T(const %T&)%>", t, t);
3222 if (!TYPE_HAS_COPY_ASSIGN (t))
3223 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3225 else if (! TYPE_HAS_COPY_ASSIGN (t))
3226 warning (OPT_Weffc__,
3227 " but does not override %<operator=(const %T&)%>", t);
3230 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3232 TYPE_PACKED (t) = 0;
3234 /* Check anonymous struct/anonymous union fields. */
3235 finish_struct_anon (t);
3237 /* We've built up the list of access declarations in reverse order.
3239 *access_decls = nreverse (*access_decls);
3242 /* If TYPE is an empty class type, records its OFFSET in the table of
3246 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3250 if (!is_empty_class (type))
3253 /* Record the location of this empty object in OFFSETS. */
3254 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3256 n = splay_tree_insert (offsets,
3257 (splay_tree_key) offset,
3258 (splay_tree_value) NULL_TREE);
3259 n->value = ((splay_tree_value)
3260 tree_cons (NULL_TREE,
3267 /* Returns nonzero if TYPE is an empty class type and there is
3268 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3271 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3276 if (!is_empty_class (type))
3279 /* Record the location of this empty object in OFFSETS. */
3280 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3284 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3285 if (same_type_p (TREE_VALUE (t), type))
3291 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3292 F for every subobject, passing it the type, offset, and table of
3293 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3296 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3297 than MAX_OFFSET will not be walked.
3299 If F returns a nonzero value, the traversal ceases, and that value
3300 is returned. Otherwise, returns zero. */
3303 walk_subobject_offsets (tree type,
3304 subobject_offset_fn f,
3311 tree type_binfo = NULL_TREE;
3313 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3315 if (max_offset && INT_CST_LT (max_offset, offset))
3318 if (type == error_mark_node)
3323 if (abi_version_at_least (2))
3325 type = BINFO_TYPE (type);
3328 if (CLASS_TYPE_P (type))
3334 /* Avoid recursing into objects that are not interesting. */
3335 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3338 /* Record the location of TYPE. */
3339 r = (*f) (type, offset, offsets);
3343 /* Iterate through the direct base classes of TYPE. */
3345 type_binfo = TYPE_BINFO (type);
3346 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3350 if (abi_version_at_least (2)
3351 && BINFO_VIRTUAL_P (binfo))
3355 && BINFO_VIRTUAL_P (binfo)
3356 && !BINFO_PRIMARY_P (binfo))
3359 if (!abi_version_at_least (2))
3360 binfo_offset = size_binop (PLUS_EXPR,
3362 BINFO_OFFSET (binfo));
3366 /* We cannot rely on BINFO_OFFSET being set for the base
3367 class yet, but the offsets for direct non-virtual
3368 bases can be calculated by going back to the TYPE. */
3369 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3370 binfo_offset = size_binop (PLUS_EXPR,
3372 BINFO_OFFSET (orig_binfo));
3375 r = walk_subobject_offsets (binfo,
3380 (abi_version_at_least (2)
3381 ? /*vbases_p=*/0 : vbases_p));
3386 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3389 VEC(tree,gc) *vbases;
3391 /* Iterate through the virtual base classes of TYPE. In G++
3392 3.2, we included virtual bases in the direct base class
3393 loop above, which results in incorrect results; the
3394 correct offsets for virtual bases are only known when
3395 working with the most derived type. */
3397 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3398 VEC_iterate (tree, vbases, ix, binfo); ix++)
3400 r = walk_subobject_offsets (binfo,
3402 size_binop (PLUS_EXPR,
3404 BINFO_OFFSET (binfo)),
3413 /* We still have to walk the primary base, if it is
3414 virtual. (If it is non-virtual, then it was walked
3416 tree vbase = get_primary_binfo (type_binfo);
3418 if (vbase && BINFO_VIRTUAL_P (vbase)
3419 && BINFO_PRIMARY_P (vbase)
3420 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3422 r = (walk_subobject_offsets
3424 offsets, max_offset, /*vbases_p=*/0));
3431 /* Iterate through the fields of TYPE. */
3432 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
3433 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3437 if (abi_version_at_least (2))
3438 field_offset = byte_position (field);
3440 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3441 field_offset = DECL_FIELD_OFFSET (field);
3443 r = walk_subobject_offsets (TREE_TYPE (field),
3445 size_binop (PLUS_EXPR,
3455 else if (TREE_CODE (type) == ARRAY_TYPE)
3457 tree element_type = strip_array_types (type);
3458 tree domain = TYPE_DOMAIN (type);
3461 /* Avoid recursing into objects that are not interesting. */
3462 if (!CLASS_TYPE_P (element_type)
3463 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3466 /* Step through each of the elements in the array. */
3467 for (index = size_zero_node;
3468 /* G++ 3.2 had an off-by-one error here. */
3469 (abi_version_at_least (2)
3470 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3471 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3472 index = size_binop (PLUS_EXPR, index, size_one_node))
3474 r = walk_subobject_offsets (TREE_TYPE (type),
3482 offset = size_binop (PLUS_EXPR, offset,
3483 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3484 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3485 there's no point in iterating through the remaining
3486 elements of the array. */
3487 if (max_offset && INT_CST_LT (max_offset, offset))
3495 /* Record all of the empty subobjects of TYPE (either a type or a
3496 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3497 is being placed at OFFSET; otherwise, it is a base class that is
3498 being placed at OFFSET. */
3501 record_subobject_offsets (tree type,
3504 bool is_data_member)
3507 /* If recording subobjects for a non-static data member or a
3508 non-empty base class , we do not need to record offsets beyond
3509 the size of the biggest empty class. Additional data members
3510 will go at the end of the class. Additional base classes will go
3511 either at offset zero (if empty, in which case they cannot
3512 overlap with offsets past the size of the biggest empty class) or
3513 at the end of the class.
3515 However, if we are placing an empty base class, then we must record
3516 all offsets, as either the empty class is at offset zero (where
3517 other empty classes might later be placed) or at the end of the
3518 class (where other objects might then be placed, so other empty
3519 subobjects might later overlap). */
3521 || !is_empty_class (BINFO_TYPE (type)))
3522 max_offset = sizeof_biggest_empty_class;
3524 max_offset = NULL_TREE;
3525 walk_subobject_offsets (type, record_subobject_offset, offset,
3526 offsets, max_offset, is_data_member);
3529 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3530 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3531 virtual bases of TYPE are examined. */
3534 layout_conflict_p (tree type,
3539 splay_tree_node max_node;
3541 /* Get the node in OFFSETS that indicates the maximum offset where
3542 an empty subobject is located. */
3543 max_node = splay_tree_max (offsets);
3544 /* If there aren't any empty subobjects, then there's no point in
3545 performing this check. */
3549 return walk_subobject_offsets (type, check_subobject_offset, offset,
3550 offsets, (tree) (max_node->key),
3554 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3555 non-static data member of the type indicated by RLI. BINFO is the
3556 binfo corresponding to the base subobject, OFFSETS maps offsets to
3557 types already located at those offsets. This function determines
3558 the position of the DECL. */
3561 layout_nonempty_base_or_field (record_layout_info rli,
3566 tree offset = NULL_TREE;
3572 /* For the purposes of determining layout conflicts, we want to
3573 use the class type of BINFO; TREE_TYPE (DECL) will be the
3574 CLASSTYPE_AS_BASE version, which does not contain entries for
3575 zero-sized bases. */
3576 type = TREE_TYPE (binfo);
3581 type = TREE_TYPE (decl);
3585 /* Try to place the field. It may take more than one try if we have
3586 a hard time placing the field without putting two objects of the
3587 same type at the same address. */
3590 struct record_layout_info_s old_rli = *rli;
3592 /* Place this field. */
3593 place_field (rli, decl);
3594 offset = byte_position (decl);
3596 /* We have to check to see whether or not there is already
3597 something of the same type at the offset we're about to use.
3598 For example, consider:
3601 struct T : public S { int i; };
3602 struct U : public S, public T {};
3604 Here, we put S at offset zero in U. Then, we can't put T at
3605 offset zero -- its S component would be at the same address
3606 as the S we already allocated. So, we have to skip ahead.
3607 Since all data members, including those whose type is an
3608 empty class, have nonzero size, any overlap can happen only
3609 with a direct or indirect base-class -- it can't happen with
3611 /* In a union, overlap is permitted; all members are placed at
3613 if (TREE_CODE (rli->t) == UNION_TYPE)
3615 /* G++ 3.2 did not check for overlaps when placing a non-empty
3617 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3619 if (layout_conflict_p (field_p ? type : binfo, offset,
3622 /* Strip off the size allocated to this field. That puts us
3623 at the first place we could have put the field with
3624 proper alignment. */
3627 /* Bump up by the alignment required for the type. */
3629 = size_binop (PLUS_EXPR, rli->bitpos,
3631 ? CLASSTYPE_ALIGN (type)
3632 : TYPE_ALIGN (type)));
3633 normalize_rli (rli);
3636 /* There was no conflict. We're done laying out this field. */
3640 /* Now that we know where it will be placed, update its
3642 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3643 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3644 this point because their BINFO_OFFSET is copied from another
3645 hierarchy. Therefore, we may not need to add the entire
3647 propagate_binfo_offsets (binfo,
3648 size_diffop_loc (input_location,
3649 convert (ssizetype, offset),
3651 BINFO_OFFSET (binfo))));
3654 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3657 empty_base_at_nonzero_offset_p (tree type,
3659 splay_tree offsets ATTRIBUTE_UNUSED)
3661 return is_empty_class (type) && !integer_zerop (offset);
3664 /* Layout the empty base BINFO. EOC indicates the byte currently just
3665 past the end of the class, and should be correctly aligned for a
3666 class of the type indicated by BINFO; OFFSETS gives the offsets of
3667 the empty bases allocated so far. T is the most derived
3668 type. Return nonzero iff we added it at the end. */
3671 layout_empty_base (record_layout_info rli, tree binfo,
3672 tree eoc, splay_tree offsets)
3675 tree basetype = BINFO_TYPE (binfo);
3678 /* This routine should only be used for empty classes. */
3679 gcc_assert (is_empty_class (basetype));
3680 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3682 if (!integer_zerop (BINFO_OFFSET (binfo)))
3684 if (abi_version_at_least (2))
3685 propagate_binfo_offsets
3686 (binfo, size_diffop_loc (input_location,
3687 size_zero_node, BINFO_OFFSET (binfo)));
3690 "offset of empty base %qT may not be ABI-compliant and may"
3691 "change in a future version of GCC",
3692 BINFO_TYPE (binfo));
3695 /* This is an empty base class. We first try to put it at offset
3697 if (layout_conflict_p (binfo,
3698 BINFO_OFFSET (binfo),
3702 /* That didn't work. Now, we move forward from the next
3703 available spot in the class. */
3705 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3708 if (!layout_conflict_p (binfo,
3709 BINFO_OFFSET (binfo),
3712 /* We finally found a spot where there's no overlap. */
3715 /* There's overlap here, too. Bump along to the next spot. */
3716 propagate_binfo_offsets (binfo, alignment);
3720 if (CLASSTYPE_USER_ALIGN (basetype))
3722 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3724 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3725 TYPE_USER_ALIGN (rli->t) = 1;
3731 /* Layout the base given by BINFO in the class indicated by RLI.
3732 *BASE_ALIGN is a running maximum of the alignments of
3733 any base class. OFFSETS gives the location of empty base
3734 subobjects. T is the most derived type. Return nonzero if the new
3735 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3736 *NEXT_FIELD, unless BINFO is for an empty base class.
3738 Returns the location at which the next field should be inserted. */
3741 build_base_field (record_layout_info rli, tree binfo,
3742 splay_tree offsets, tree *next_field)
3745 tree basetype = BINFO_TYPE (binfo);
3747 if (!COMPLETE_TYPE_P (basetype))
3748 /* This error is now reported in xref_tag, thus giving better
3749 location information. */
3752 /* Place the base class. */
3753 if (!is_empty_class (basetype))
3757 /* The containing class is non-empty because it has a non-empty
3759 CLASSTYPE_EMPTY_P (t) = 0;
3761 /* Create the FIELD_DECL. */
3762 decl = build_decl (input_location,
3763 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3764 DECL_ARTIFICIAL (decl) = 1;
3765 DECL_IGNORED_P (decl) = 1;
3766 DECL_FIELD_CONTEXT (decl) = t;
3767 if (CLASSTYPE_AS_BASE (basetype))
3769 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3770 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3771 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3772 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3773 DECL_MODE (decl) = TYPE_MODE (basetype);
3774 DECL_FIELD_IS_BASE (decl) = 1;
3776 /* Try to place the field. It may take more than one try if we
3777 have a hard time placing the field without putting two
3778 objects of the same type at the same address. */
3779 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3780 /* Add the new FIELD_DECL to the list of fields for T. */
3781 DECL_CHAIN (decl) = *next_field;
3783 next_field = &DECL_CHAIN (decl);
3791 /* On some platforms (ARM), even empty classes will not be
3793 eoc = round_up_loc (input_location,
3794 rli_size_unit_so_far (rli),
3795 CLASSTYPE_ALIGN_UNIT (basetype));
3796 atend = layout_empty_base (rli, binfo, eoc, offsets);
3797 /* A nearly-empty class "has no proper base class that is empty,
3798 not morally virtual, and at an offset other than zero." */
3799 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3802 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3803 /* The check above (used in G++ 3.2) is insufficient because
3804 an empty class placed at offset zero might itself have an
3805 empty base at a nonzero offset. */
3806 else if (walk_subobject_offsets (basetype,
3807 empty_base_at_nonzero_offset_p,
3810 /*max_offset=*/NULL_TREE,
3813 if (abi_version_at_least (2))
3814 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3817 "class %qT will be considered nearly empty in a "
3818 "future version of GCC", t);
3822 /* We do not create a FIELD_DECL for empty base classes because
3823 it might overlap some other field. We want to be able to
3824 create CONSTRUCTORs for the class by iterating over the
3825 FIELD_DECLs, and the back end does not handle overlapping
3828 /* An empty virtual base causes a class to be non-empty
3829 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3830 here because that was already done when the virtual table
3831 pointer was created. */
3834 /* Record the offsets of BINFO and its base subobjects. */
3835 record_subobject_offsets (binfo,
3836 BINFO_OFFSET (binfo),
3838 /*is_data_member=*/false);
3843 /* Layout all of the non-virtual base classes. Record empty
3844 subobjects in OFFSETS. T is the most derived type. Return nonzero
3845 if the type cannot be nearly empty. The fields created
3846 corresponding to the base classes will be inserted at
3850 build_base_fields (record_layout_info rli,
3851 splay_tree offsets, tree *next_field)
3853 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3856 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3859 /* The primary base class is always allocated first. */
3860 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3861 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3862 offsets, next_field);
3864 /* Now allocate the rest of the bases. */
3865 for (i = 0; i < n_baseclasses; ++i)
3869 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3871 /* The primary base was already allocated above, so we don't
3872 need to allocate it again here. */
3873 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3876 /* Virtual bases are added at the end (a primary virtual base
3877 will have already been added). */
3878 if (BINFO_VIRTUAL_P (base_binfo))
3881 next_field = build_base_field (rli, base_binfo,
3882 offsets, next_field);
3886 /* Go through the TYPE_METHODS of T issuing any appropriate
3887 diagnostics, figuring out which methods override which other
3888 methods, and so forth. */
3891 check_methods (tree t)
3895 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
3897 check_for_override (x, t);
3898 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3899 error ("initializer specified for non-virtual method %q+D", x);
3900 /* The name of the field is the original field name
3901 Save this in auxiliary field for later overloading. */
3902 if (DECL_VINDEX (x))
3904 TYPE_POLYMORPHIC_P (t) = 1;
3905 if (DECL_PURE_VIRTUAL_P (x))
3906 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3908 /* All user-provided destructors are non-trivial.
3909 Constructors and assignment ops are handled in
3910 grok_special_member_properties. */
3911 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
3912 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3916 /* FN is a constructor or destructor. Clone the declaration to create
3917 a specialized in-charge or not-in-charge version, as indicated by
3921 build_clone (tree fn, tree name)
3926 /* Copy the function. */
3927 clone = copy_decl (fn);
3928 /* Reset the function name. */
3929 DECL_NAME (clone) = name;
3930 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3931 /* Remember where this function came from. */
3932 DECL_ABSTRACT_ORIGIN (clone) = fn;
3933 /* Make it easy to find the CLONE given the FN. */
3934 DECL_CHAIN (clone) = DECL_CHAIN (fn);
3935 DECL_CHAIN (fn) = clone;
3937 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3938 if (TREE_CODE (clone) == TEMPLATE_DECL)
3940 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3941 DECL_TEMPLATE_RESULT (clone) = result;
3942 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3943 DECL_TI_TEMPLATE (result) = clone;
3944 TREE_TYPE (clone) = TREE_TYPE (result);
3948 DECL_CLONED_FUNCTION (clone) = fn;
3949 /* There's no pending inline data for this function. */
3950 DECL_PENDING_INLINE_INFO (clone) = NULL;
3951 DECL_PENDING_INLINE_P (clone) = 0;
3953 /* The base-class destructor is not virtual. */
3954 if (name == base_dtor_identifier)
3956 DECL_VIRTUAL_P (clone) = 0;
3957 if (TREE_CODE (clone) != TEMPLATE_DECL)
3958 DECL_VINDEX (clone) = NULL_TREE;
3961 /* If there was an in-charge parameter, drop it from the function
3963 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3969 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3970 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3971 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3972 /* Skip the `this' parameter. */
3973 parmtypes = TREE_CHAIN (parmtypes);
3974 /* Skip the in-charge parameter. */
3975 parmtypes = TREE_CHAIN (parmtypes);
3976 /* And the VTT parm, in a complete [cd]tor. */
3977 if (DECL_HAS_VTT_PARM_P (fn)
3978 && ! DECL_NEEDS_VTT_PARM_P (clone))
3979 parmtypes = TREE_CHAIN (parmtypes);
3980 /* If this is subobject constructor or destructor, add the vtt
3983 = build_method_type_directly (basetype,
3984 TREE_TYPE (TREE_TYPE (clone)),
3987 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3990 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3991 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3994 /* Copy the function parameters. */
3995 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3996 /* Remove the in-charge parameter. */
3997 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3999 DECL_CHAIN (DECL_ARGUMENTS (clone))
4000 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4001 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
4003 /* And the VTT parm, in a complete [cd]tor. */
4004 if (DECL_HAS_VTT_PARM_P (fn))
4006 if (DECL_NEEDS_VTT_PARM_P (clone))
4007 DECL_HAS_VTT_PARM_P (clone) = 1;
4010 DECL_CHAIN (DECL_ARGUMENTS (clone))
4011 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4012 DECL_HAS_VTT_PARM_P (clone) = 0;
4016 for (parms = DECL_ARGUMENTS (clone); parms; parms = DECL_CHAIN (parms))
4018 DECL_CONTEXT (parms) = clone;
4019 cxx_dup_lang_specific_decl (parms);
4022 /* Create the RTL for this function. */
4023 SET_DECL_RTL (clone, NULL);
4024 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
4027 note_decl_for_pch (clone);
4032 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4033 not invoke this function directly.
4035 For a non-thunk function, returns the address of the slot for storing
4036 the function it is a clone of. Otherwise returns NULL_TREE.
4038 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4039 cloned_function is unset. This is to support the separate
4040 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4041 on a template makes sense, but not the former. */
4044 decl_cloned_function_p (const_tree decl, bool just_testing)
4048 decl = STRIP_TEMPLATE (decl);
4050 if (TREE_CODE (decl) != FUNCTION_DECL
4051 || !DECL_LANG_SPECIFIC (decl)
4052 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
4054 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4056 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
4062 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
4063 if (just_testing && *ptr == NULL_TREE)
4069 /* Produce declarations for all appropriate clones of FN. If
4070 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4071 CLASTYPE_METHOD_VEC as well. */
4074 clone_function_decl (tree fn, int update_method_vec_p)
4078 /* Avoid inappropriate cloning. */
4080 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (fn)))
4083 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4085 /* For each constructor, we need two variants: an in-charge version
4086 and a not-in-charge version. */
4087 clone = build_clone (fn, complete_ctor_identifier);
4088 if (update_method_vec_p)
4089 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4090 clone = build_clone (fn, base_ctor_identifier);
4091 if (update_method_vec_p)
4092 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4096 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4098 /* For each destructor, we need three variants: an in-charge
4099 version, a not-in-charge version, and an in-charge deleting
4100 version. We clone the deleting version first because that
4101 means it will go second on the TYPE_METHODS list -- and that
4102 corresponds to the correct layout order in the virtual
4105 For a non-virtual destructor, we do not build a deleting
4107 if (DECL_VIRTUAL_P (fn))
4109 clone = build_clone (fn, deleting_dtor_identifier);
4110 if (update_method_vec_p)
4111 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4113 clone = build_clone (fn, complete_dtor_identifier);
4114 if (update_method_vec_p)
4115 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4116 clone = build_clone (fn, base_dtor_identifier);
4117 if (update_method_vec_p)
4118 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4121 /* Note that this is an abstract function that is never emitted. */
4122 DECL_ABSTRACT (fn) = 1;
4125 /* DECL is an in charge constructor, which is being defined. This will
4126 have had an in class declaration, from whence clones were
4127 declared. An out-of-class definition can specify additional default
4128 arguments. As it is the clones that are involved in overload
4129 resolution, we must propagate the information from the DECL to its
4133 adjust_clone_args (tree decl)
4137 for (clone = DECL_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4138 clone = DECL_CHAIN (clone))
4140 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4141 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4142 tree decl_parms, clone_parms;
4144 clone_parms = orig_clone_parms;
4146 /* Skip the 'this' parameter. */
4147 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4148 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4150 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4151 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4152 if (DECL_HAS_VTT_PARM_P (decl))
4153 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4155 clone_parms = orig_clone_parms;
4156 if (DECL_HAS_VTT_PARM_P (clone))
4157 clone_parms = TREE_CHAIN (clone_parms);
4159 for (decl_parms = orig_decl_parms; decl_parms;
4160 decl_parms = TREE_CHAIN (decl_parms),
4161 clone_parms = TREE_CHAIN (clone_parms))
4163 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4164 TREE_TYPE (clone_parms)));
4166 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4168 /* A default parameter has been added. Adjust the
4169 clone's parameters. */
4170 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4171 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4172 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4175 clone_parms = orig_decl_parms;
4177 if (DECL_HAS_VTT_PARM_P (clone))
4179 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4180 TREE_VALUE (orig_clone_parms),
4182 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4184 type = build_method_type_directly (basetype,
4185 TREE_TYPE (TREE_TYPE (clone)),
4188 type = build_exception_variant (type, exceptions);
4190 type = cp_build_type_attribute_variant (type, attrs);
4191 TREE_TYPE (clone) = type;
4193 clone_parms = NULL_TREE;
4197 gcc_assert (!clone_parms);
4201 /* For each of the constructors and destructors in T, create an
4202 in-charge and not-in-charge variant. */
4205 clone_constructors_and_destructors (tree t)
4209 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4211 if (!CLASSTYPE_METHOD_VEC (t))
4214 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4215 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4216 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4217 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4220 /* Returns true iff class T has a user-defined constructor other than
4221 the default constructor. */
4224 type_has_user_nondefault_constructor (tree t)
4228 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4231 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4233 tree fn = OVL_CURRENT (fns);
4234 if (!DECL_ARTIFICIAL (fn)
4235 && (TREE_CODE (fn) == TEMPLATE_DECL
4236 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4244 /* Returns the defaulted constructor if T has one. Otherwise, returns
4248 in_class_defaulted_default_constructor (tree t)
4252 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4255 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4257 tree fn = OVL_CURRENT (fns);
4259 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4261 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4262 while (args && TREE_PURPOSE (args))
4263 args = TREE_CHAIN (args);
4264 if (!args || args == void_list_node)
4272 /* Returns true iff FN is a user-provided function, i.e. user-declared
4273 and not defaulted at its first declaration; or explicit, private,
4274 protected, or non-const. */
4277 user_provided_p (tree fn)
4279 if (TREE_CODE (fn) == TEMPLATE_DECL)
4282 return (!DECL_ARTIFICIAL (fn)
4283 && !DECL_DEFAULTED_IN_CLASS_P (fn));
4286 /* Returns true iff class T has a user-provided constructor. */
4289 type_has_user_provided_constructor (tree t)
4293 if (!CLASS_TYPE_P (t))
4296 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4299 /* This can happen in error cases; avoid crashing. */
4300 if (!CLASSTYPE_METHOD_VEC (t))
4303 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4304 if (user_provided_p (OVL_CURRENT (fns)))
4310 /* Returns true iff class T has a user-provided default constructor. */
4313 type_has_user_provided_default_constructor (tree t)
4317 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4320 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4322 tree fn = OVL_CURRENT (fns);
4323 if (TREE_CODE (fn) == FUNCTION_DECL
4324 && user_provided_p (fn)
4325 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)))
4332 /* Returns true iff for class T, a synthesized default constructor
4333 would be constexpr. */
4336 synthesized_default_constructor_is_constexpr (tree t)
4338 /* A defaulted default constructor is constexpr
4339 if there is nothing to initialize. */
4340 /* FIXME adjust for non-static data member initializers. */
4341 return is_really_empty_class (t);
4344 /* Returns true iff class T has a constexpr default constructor. */
4347 type_has_constexpr_default_constructor (tree t)
4351 if (!CLASS_TYPE_P (t))
4353 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t))
4354 return synthesized_default_constructor_is_constexpr (t);
4355 fns = locate_ctor (t);
4356 return (fns && DECL_DECLARED_CONSTEXPR_P (fns));
4359 /* Returns true iff class TYPE has a virtual destructor. */
4362 type_has_virtual_destructor (tree type)
4366 if (!CLASS_TYPE_P (type))
4369 gcc_assert (COMPLETE_TYPE_P (type));
4370 dtor = CLASSTYPE_DESTRUCTORS (type);
4371 return (dtor && DECL_VIRTUAL_P (dtor));
4374 /* Returns true iff class T has a move constructor. */
4377 type_has_move_constructor (tree t)
4381 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4383 gcc_assert (COMPLETE_TYPE_P (t));
4384 lazily_declare_fn (sfk_move_constructor, t);
4387 if (!CLASSTYPE_METHOD_VEC (t))
4390 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4391 if (move_fn_p (OVL_CURRENT (fns)))
4397 /* Returns true iff class T has a move assignment operator. */
4400 type_has_move_assign (tree t)
4404 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4406 gcc_assert (COMPLETE_TYPE_P (t));
4407 lazily_declare_fn (sfk_move_assignment, t);
4410 for (fns = lookup_fnfields_slot (t, ansi_assopname (NOP_EXPR));
4411 fns; fns = OVL_NEXT (fns))
4412 if (move_fn_p (OVL_CURRENT (fns)))
4418 /* Remove all zero-width bit-fields from T. */
4421 remove_zero_width_bit_fields (tree t)
4425 fieldsp = &TYPE_FIELDS (t);
4428 if (TREE_CODE (*fieldsp) == FIELD_DECL
4429 && DECL_C_BIT_FIELD (*fieldsp)
4430 /* We should not be confused by the fact that grokbitfield
4431 temporarily sets the width of the bit field into
4432 DECL_INITIAL (*fieldsp).
4433 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4435 && integer_zerop (DECL_SIZE (*fieldsp)))
4436 *fieldsp = DECL_CHAIN (*fieldsp);
4438 fieldsp = &DECL_CHAIN (*fieldsp);
4442 /* Returns TRUE iff we need a cookie when dynamically allocating an
4443 array whose elements have the indicated class TYPE. */
4446 type_requires_array_cookie (tree type)
4449 bool has_two_argument_delete_p = false;
4451 gcc_assert (CLASS_TYPE_P (type));
4453 /* If there's a non-trivial destructor, we need a cookie. In order
4454 to iterate through the array calling the destructor for each
4455 element, we'll have to know how many elements there are. */
4456 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4459 /* If the usual deallocation function is a two-argument whose second
4460 argument is of type `size_t', then we have to pass the size of
4461 the array to the deallocation function, so we will need to store
4463 fns = lookup_fnfields (TYPE_BINFO (type),
4464 ansi_opname (VEC_DELETE_EXPR),
4466 /* If there are no `operator []' members, or the lookup is
4467 ambiguous, then we don't need a cookie. */
4468 if (!fns || fns == error_mark_node)
4470 /* Loop through all of the functions. */
4471 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4476 /* Select the current function. */
4477 fn = OVL_CURRENT (fns);
4478 /* See if this function is a one-argument delete function. If
4479 it is, then it will be the usual deallocation function. */
4480 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4481 if (second_parm == void_list_node)
4483 /* Do not consider this function if its second argument is an
4487 /* Otherwise, if we have a two-argument function and the second
4488 argument is `size_t', it will be the usual deallocation
4489 function -- unless there is one-argument function, too. */
4490 if (TREE_CHAIN (second_parm) == void_list_node
4491 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4492 has_two_argument_delete_p = true;
4495 return has_two_argument_delete_p;
4498 /* Finish computing the `literal type' property of class type T.
4500 At this point, we have already processed base classes and
4501 non-static data members. We need to check whether the copy
4502 constructor is trivial, the destructor is trivial, and there
4503 is a trivial default constructor or at least one constexpr
4504 constructor other than the copy constructor. */
4507 finalize_literal_type_property (tree t)
4509 if (cxx_dialect < cxx0x
4510 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
4511 /* FIXME These constraints seem unnecessary; remove from standard.
4512 || !TYPE_HAS_TRIVIAL_COPY_CTOR (t)
4513 || TYPE_HAS_COMPLEX_MOVE_CTOR (t)*/ )
4514 CLASSTYPE_LITERAL_P (t) = false;
4515 else if (CLASSTYPE_LITERAL_P (t) && !TYPE_HAS_TRIVIAL_DFLT (t)
4516 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4517 CLASSTYPE_LITERAL_P (t) = false;
4519 if (!CLASSTYPE_LITERAL_P (t) && !CLASSTYPE_TEMPLATE_INSTANTIATION (t))
4522 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4523 if (DECL_DECLARED_CONSTEXPR_P (fn)
4524 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
4525 && !DECL_CONSTRUCTOR_P (fn))
4527 error ("enclosing class of %q+D is not a literal type", fn);
4528 DECL_DECLARED_CONSTEXPR_P (fn) = false;
4533 /* Check the validity of the bases and members declared in T. Add any
4534 implicitly-generated functions (like copy-constructors and
4535 assignment operators). Compute various flag bits (like
4536 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4537 level: i.e., independently of the ABI in use. */
4540 check_bases_and_members (tree t)
4542 /* Nonzero if the implicitly generated copy constructor should take
4543 a non-const reference argument. */
4544 int cant_have_const_ctor;
4545 /* Nonzero if the implicitly generated assignment operator
4546 should take a non-const reference argument. */
4547 int no_const_asn_ref;
4549 bool saved_complex_asn_ref;
4550 bool saved_nontrivial_dtor;
4553 /* By default, we use const reference arguments and generate default
4555 cant_have_const_ctor = 0;
4556 no_const_asn_ref = 0;
4558 /* Check all the base-classes. */
4559 check_bases (t, &cant_have_const_ctor,
4562 /* Check all the method declarations. */
4565 /* Save the initial values of these flags which only indicate whether
4566 or not the class has user-provided functions. As we analyze the
4567 bases and members we can set these flags for other reasons. */
4568 saved_complex_asn_ref = TYPE_HAS_COMPLEX_COPY_ASSIGN (t);
4569 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4571 /* Check all the data member declarations. We cannot call
4572 check_field_decls until we have called check_bases check_methods,
4573 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4574 being set appropriately. */
4575 check_field_decls (t, &access_decls,
4576 &cant_have_const_ctor,
4579 /* A nearly-empty class has to be vptr-containing; a nearly empty
4580 class contains just a vptr. */
4581 if (!TYPE_CONTAINS_VPTR_P (t))
4582 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4584 /* Do some bookkeeping that will guide the generation of implicitly
4585 declared member functions. */
4586 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4587 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4588 /* We need to call a constructor for this class if it has a
4589 user-provided constructor, or if the default constructor is going
4590 to initialize the vptr. (This is not an if-and-only-if;
4591 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4592 themselves need constructing.) */
4593 TYPE_NEEDS_CONSTRUCTING (t)
4594 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4597 An aggregate is an array or a class with no user-provided
4598 constructors ... and no virtual functions.
4600 Again, other conditions for being an aggregate are checked
4602 CLASSTYPE_NON_AGGREGATE (t)
4603 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4604 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4605 retain the old definition internally for ABI reasons. */
4606 CLASSTYPE_NON_LAYOUT_POD_P (t)
4607 |= (CLASSTYPE_NON_AGGREGATE (t)
4608 || saved_nontrivial_dtor || saved_complex_asn_ref);
4609 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
4610 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4611 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4612 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4614 /* If the class has no user-declared constructor, but does have
4615 non-static const or reference data members that can never be
4616 initialized, issue a warning. */
4617 if (warn_uninitialized
4618 /* Classes with user-declared constructors are presumed to
4619 initialize these members. */
4620 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4621 /* Aggregates can be initialized with brace-enclosed
4623 && CLASSTYPE_NON_AGGREGATE (t))
4627 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
4631 if (TREE_CODE (field) != FIELD_DECL)
4634 type = TREE_TYPE (field);
4635 if (TREE_CODE (type) == REFERENCE_TYPE)
4636 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4637 "in class without a constructor", field);
4638 else if (CP_TYPE_CONST_P (type)
4639 && (!CLASS_TYPE_P (type)
4640 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4641 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4642 "in class without a constructor", field);
4646 /* Synthesize any needed methods. */
4647 add_implicitly_declared_members (t,
4648 cant_have_const_ctor,
4651 /* Check defaulted declarations here so we have cant_have_const_ctor
4652 and don't need to worry about clones. */
4653 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4654 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4656 int copy = copy_fn_p (fn);
4660 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
4661 : !no_const_asn_ref);
4662 bool fn_const_p = (copy == 2);
4664 if (fn_const_p && !imp_const_p)
4665 /* If the function is defaulted outside the class, we just
4666 give the synthesis error. */
4667 error ("%q+D declared to take const reference, but implicit "
4668 "declaration would take non-const", fn);
4669 else if (imp_const_p && !fn_const_p)
4670 error ("%q+D declared to take non-const reference cannot be "
4671 "defaulted in the class body", fn);
4673 defaulted_late_check (fn);
4676 if (LAMBDA_TYPE_P (t))
4678 /* "The closure type associated with a lambda-expression has a deleted
4679 default constructor and a deleted copy assignment operator." */
4680 TYPE_NEEDS_CONSTRUCTING (t) = 1;
4681 TYPE_HAS_COMPLEX_DFLT (t) = 1;
4682 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
4683 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 0;
4685 /* "This class type is not an aggregate." */
4686 CLASSTYPE_NON_AGGREGATE (t) = 1;
4689 /* Compute the 'literal type' property before we
4690 do anything with non-static member functions. */
4691 finalize_literal_type_property (t);
4693 /* Create the in-charge and not-in-charge variants of constructors
4695 clone_constructors_and_destructors (t);
4697 /* Process the using-declarations. */
4698 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4699 handle_using_decl (TREE_VALUE (access_decls), t);
4701 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4702 finish_struct_methods (t);
4704 /* Figure out whether or not we will need a cookie when dynamically
4705 allocating an array of this type. */
4706 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4707 = type_requires_array_cookie (t);
4710 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4711 accordingly. If a new vfield was created (because T doesn't have a
4712 primary base class), then the newly created field is returned. It
4713 is not added to the TYPE_FIELDS list; it is the caller's
4714 responsibility to do that. Accumulate declared virtual functions
4718 create_vtable_ptr (tree t, tree* virtuals_p)
4722 /* Collect the virtual functions declared in T. */
4723 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4724 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4725 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4727 tree new_virtual = make_node (TREE_LIST);
4729 BV_FN (new_virtual) = fn;
4730 BV_DELTA (new_virtual) = integer_zero_node;
4731 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4733 TREE_CHAIN (new_virtual) = *virtuals_p;
4734 *virtuals_p = new_virtual;
4737 /* If we couldn't find an appropriate base class, create a new field
4738 here. Even if there weren't any new virtual functions, we might need a
4739 new virtual function table if we're supposed to include vptrs in
4740 all classes that need them. */
4741 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4743 /* We build this decl with vtbl_ptr_type_node, which is a
4744 `vtable_entry_type*'. It might seem more precise to use
4745 `vtable_entry_type (*)[N]' where N is the number of virtual
4746 functions. However, that would require the vtable pointer in
4747 base classes to have a different type than the vtable pointer
4748 in derived classes. We could make that happen, but that
4749 still wouldn't solve all the problems. In particular, the
4750 type-based alias analysis code would decide that assignments
4751 to the base class vtable pointer can't alias assignments to
4752 the derived class vtable pointer, since they have different
4753 types. Thus, in a derived class destructor, where the base
4754 class constructor was inlined, we could generate bad code for
4755 setting up the vtable pointer.
4757 Therefore, we use one type for all vtable pointers. We still
4758 use a type-correct type; it's just doesn't indicate the array
4759 bounds. That's better than using `void*' or some such; it's
4760 cleaner, and it let's the alias analysis code know that these
4761 stores cannot alias stores to void*! */
4764 field = build_decl (input_location,
4765 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4766 DECL_VIRTUAL_P (field) = 1;
4767 DECL_ARTIFICIAL (field) = 1;
4768 DECL_FIELD_CONTEXT (field) = t;
4769 DECL_FCONTEXT (field) = t;
4770 if (TYPE_PACKED (t))
4771 DECL_PACKED (field) = 1;
4773 TYPE_VFIELD (t) = field;
4775 /* This class is non-empty. */
4776 CLASSTYPE_EMPTY_P (t) = 0;
4784 /* Add OFFSET to all base types of BINFO which is a base in the
4785 hierarchy dominated by T.
4787 OFFSET, which is a type offset, is number of bytes. */
4790 propagate_binfo_offsets (tree binfo, tree offset)
4796 /* Update BINFO's offset. */
4797 BINFO_OFFSET (binfo)
4798 = convert (sizetype,
4799 size_binop (PLUS_EXPR,
4800 convert (ssizetype, BINFO_OFFSET (binfo)),
4803 /* Find the primary base class. */
4804 primary_binfo = get_primary_binfo (binfo);
4806 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4807 propagate_binfo_offsets (primary_binfo, offset);
4809 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4811 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4813 /* Don't do the primary base twice. */
4814 if (base_binfo == primary_binfo)
4817 if (BINFO_VIRTUAL_P (base_binfo))
4820 propagate_binfo_offsets (base_binfo, offset);
4824 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4825 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4826 empty subobjects of T. */
4829 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4833 bool first_vbase = true;
4836 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4839 if (!abi_version_at_least(2))
4841 /* In G++ 3.2, we incorrectly rounded the size before laying out
4842 the virtual bases. */
4843 finish_record_layout (rli, /*free_p=*/false);
4844 #ifdef STRUCTURE_SIZE_BOUNDARY
4845 /* Packed structures don't need to have minimum size. */
4846 if (! TYPE_PACKED (t))
4847 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4849 rli->offset = TYPE_SIZE_UNIT (t);
4850 rli->bitpos = bitsize_zero_node;
4851 rli->record_align = TYPE_ALIGN (t);
4854 /* Find the last field. The artificial fields created for virtual
4855 bases will go after the last extant field to date. */
4856 next_field = &TYPE_FIELDS (t);
4858 next_field = &DECL_CHAIN (*next_field);
4860 /* Go through the virtual bases, allocating space for each virtual
4861 base that is not already a primary base class. These are
4862 allocated in inheritance graph order. */
4863 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4865 if (!BINFO_VIRTUAL_P (vbase))
4868 if (!BINFO_PRIMARY_P (vbase))
4870 tree basetype = TREE_TYPE (vbase);
4872 /* This virtual base is not a primary base of any class in the
4873 hierarchy, so we have to add space for it. */
4874 next_field = build_base_field (rli, vbase,
4875 offsets, next_field);
4877 /* If the first virtual base might have been placed at a
4878 lower address, had we started from CLASSTYPE_SIZE, rather
4879 than TYPE_SIZE, issue a warning. There can be both false
4880 positives and false negatives from this warning in rare
4881 cases; to deal with all the possibilities would probably
4882 require performing both layout algorithms and comparing
4883 the results which is not particularly tractable. */
4887 (size_binop (CEIL_DIV_EXPR,
4888 round_up_loc (input_location,
4890 CLASSTYPE_ALIGN (basetype)),
4892 BINFO_OFFSET (vbase))))
4894 "offset of virtual base %qT is not ABI-compliant and "
4895 "may change in a future version of GCC",
4898 first_vbase = false;
4903 /* Returns the offset of the byte just past the end of the base class
4907 end_of_base (tree binfo)
4911 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
4912 size = TYPE_SIZE_UNIT (char_type_node);
4913 else if (is_empty_class (BINFO_TYPE (binfo)))
4914 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4915 allocate some space for it. It cannot have virtual bases, so
4916 TYPE_SIZE_UNIT is fine. */
4917 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4919 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4921 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4924 /* Returns the offset of the byte just past the end of the base class
4925 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4926 only non-virtual bases are included. */
4929 end_of_class (tree t, int include_virtuals_p)
4931 tree result = size_zero_node;
4932 VEC(tree,gc) *vbases;
4938 for (binfo = TYPE_BINFO (t), i = 0;
4939 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4941 if (!include_virtuals_p
4942 && BINFO_VIRTUAL_P (base_binfo)
4943 && (!BINFO_PRIMARY_P (base_binfo)
4944 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4947 offset = end_of_base (base_binfo);
4948 if (INT_CST_LT_UNSIGNED (result, offset))
4952 /* G++ 3.2 did not check indirect virtual bases. */
4953 if (abi_version_at_least (2) && include_virtuals_p)
4954 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4955 VEC_iterate (tree, vbases, i, base_binfo); i++)
4957 offset = end_of_base (base_binfo);
4958 if (INT_CST_LT_UNSIGNED (result, offset))
4965 /* Warn about bases of T that are inaccessible because they are
4966 ambiguous. For example:
4969 struct T : public S {};
4970 struct U : public S, public T {};
4972 Here, `(S*) new U' is not allowed because there are two `S'
4976 warn_about_ambiguous_bases (tree t)
4979 VEC(tree,gc) *vbases;
4984 /* If there are no repeated bases, nothing can be ambiguous. */
4985 if (!CLASSTYPE_REPEATED_BASE_P (t))
4988 /* Check direct bases. */
4989 for (binfo = TYPE_BINFO (t), i = 0;
4990 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4992 basetype = BINFO_TYPE (base_binfo);
4994 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4995 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4999 /* Check for ambiguous virtual bases. */
5001 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5002 VEC_iterate (tree, vbases, i, binfo); i++)
5004 basetype = BINFO_TYPE (binfo);
5006 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5007 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
5012 /* Compare two INTEGER_CSTs K1 and K2. */
5015 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
5017 return tree_int_cst_compare ((tree) k1, (tree) k2);
5020 /* Increase the size indicated in RLI to account for empty classes
5021 that are "off the end" of the class. */
5024 include_empty_classes (record_layout_info rli)
5029 /* It might be the case that we grew the class to allocate a
5030 zero-sized base class. That won't be reflected in RLI, yet,
5031 because we are willing to overlay multiple bases at the same
5032 offset. However, now we need to make sure that RLI is big enough
5033 to reflect the entire class. */
5034 eoc = end_of_class (rli->t,
5035 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
5036 rli_size = rli_size_unit_so_far (rli);
5037 if (TREE_CODE (rli_size) == INTEGER_CST
5038 && INT_CST_LT_UNSIGNED (rli_size, eoc))
5040 if (!abi_version_at_least (2))
5041 /* In version 1 of the ABI, the size of a class that ends with
5042 a bitfield was not rounded up to a whole multiple of a
5043 byte. Because rli_size_unit_so_far returns only the number
5044 of fully allocated bytes, any extra bits were not included
5046 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
5048 /* The size should have been rounded to a whole byte. */
5049 gcc_assert (tree_int_cst_equal
5050 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
5052 = size_binop (PLUS_EXPR,
5054 size_binop (MULT_EXPR,
5055 convert (bitsizetype,
5056 size_binop (MINUS_EXPR,
5058 bitsize_int (BITS_PER_UNIT)));
5059 normalize_rli (rli);
5063 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
5064 BINFO_OFFSETs for all of the base-classes. Position the vtable
5065 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
5068 layout_class_type (tree t, tree *virtuals_p)
5070 tree non_static_data_members;
5073 record_layout_info rli;
5074 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
5075 types that appear at that offset. */
5076 splay_tree empty_base_offsets;
5077 /* True if the last field layed out was a bit-field. */
5078 bool last_field_was_bitfield = false;
5079 /* The location at which the next field should be inserted. */
5081 /* T, as a base class. */
5084 /* Keep track of the first non-static data member. */
5085 non_static_data_members = TYPE_FIELDS (t);
5087 /* Start laying out the record. */
5088 rli = start_record_layout (t);
5090 /* Mark all the primary bases in the hierarchy. */
5091 determine_primary_bases (t);
5093 /* Create a pointer to our virtual function table. */
5094 vptr = create_vtable_ptr (t, virtuals_p);
5096 /* The vptr is always the first thing in the class. */
5099 DECL_CHAIN (vptr) = TYPE_FIELDS (t);
5100 TYPE_FIELDS (t) = vptr;
5101 next_field = &DECL_CHAIN (vptr);
5102 place_field (rli, vptr);
5105 next_field = &TYPE_FIELDS (t);
5107 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5108 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
5110 build_base_fields (rli, empty_base_offsets, next_field);
5112 /* Layout the non-static data members. */
5113 for (field = non_static_data_members; field; field = DECL_CHAIN (field))
5118 /* We still pass things that aren't non-static data members to
5119 the back end, in case it wants to do something with them. */
5120 if (TREE_CODE (field) != FIELD_DECL)
5122 place_field (rli, field);
5123 /* If the static data member has incomplete type, keep track
5124 of it so that it can be completed later. (The handling
5125 of pending statics in finish_record_layout is
5126 insufficient; consider:
5129 struct S2 { static S1 s1; };
5131 At this point, finish_record_layout will be called, but
5132 S1 is still incomplete.) */
5133 if (TREE_CODE (field) == VAR_DECL)
5135 maybe_register_incomplete_var (field);
5136 /* The visibility of static data members is determined
5137 at their point of declaration, not their point of
5139 determine_visibility (field);
5144 type = TREE_TYPE (field);
5145 if (type == error_mark_node)
5148 padding = NULL_TREE;
5150 /* If this field is a bit-field whose width is greater than its
5151 type, then there are some special rules for allocating
5153 if (DECL_C_BIT_FIELD (field)
5154 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
5158 bool was_unnamed_p = false;
5159 /* We must allocate the bits as if suitably aligned for the
5160 longest integer type that fits in this many bits. type
5161 of the field. Then, we are supposed to use the left over
5162 bits as additional padding. */
5163 for (itk = itk_char; itk != itk_none; ++itk)
5164 if (integer_types[itk] != NULL_TREE
5165 && (INT_CST_LT (size_int (MAX_FIXED_MODE_SIZE),
5166 TYPE_SIZE (integer_types[itk]))
5167 || INT_CST_LT (DECL_SIZE (field),
5168 TYPE_SIZE (integer_types[itk]))))
5171 /* ITK now indicates a type that is too large for the
5172 field. We have to back up by one to find the largest
5177 integer_type = integer_types[itk];
5178 } while (itk > 0 && integer_type == NULL_TREE);
5180 /* Figure out how much additional padding is required. GCC
5181 3.2 always created a padding field, even if it had zero
5183 if (!abi_version_at_least (2)
5184 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
5186 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
5187 /* In a union, the padding field must have the full width
5188 of the bit-field; all fields start at offset zero. */
5189 padding = DECL_SIZE (field);
5192 if (TREE_CODE (t) == UNION_TYPE)
5193 warning (OPT_Wabi, "size assigned to %qT may not be "
5194 "ABI-compliant and may change in a future "
5197 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
5198 TYPE_SIZE (integer_type));
5201 #ifdef PCC_BITFIELD_TYPE_MATTERS
5202 /* An unnamed bitfield does not normally affect the
5203 alignment of the containing class on a target where
5204 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5205 make any exceptions for unnamed bitfields when the
5206 bitfields are longer than their types. Therefore, we
5207 temporarily give the field a name. */
5208 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
5210 was_unnamed_p = true;
5211 DECL_NAME (field) = make_anon_name ();
5214 DECL_SIZE (field) = TYPE_SIZE (integer_type);
5215 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
5216 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
5217 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5218 empty_base_offsets);
5220 DECL_NAME (field) = NULL_TREE;
5221 /* Now that layout has been performed, set the size of the
5222 field to the size of its declared type; the rest of the
5223 field is effectively invisible. */
5224 DECL_SIZE (field) = TYPE_SIZE (type);
5225 /* We must also reset the DECL_MODE of the field. */
5226 if (abi_version_at_least (2))
5227 DECL_MODE (field) = TYPE_MODE (type);
5229 && DECL_MODE (field) != TYPE_MODE (type))
5230 /* Versions of G++ before G++ 3.4 did not reset the
5233 "the offset of %qD may not be ABI-compliant and may "
5234 "change in a future version of GCC", field);
5237 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5238 empty_base_offsets);
5240 /* Remember the location of any empty classes in FIELD. */
5241 if (abi_version_at_least (2))
5242 record_subobject_offsets (TREE_TYPE (field),
5243 byte_position(field),
5245 /*is_data_member=*/true);
5247 /* If a bit-field does not immediately follow another bit-field,
5248 and yet it starts in the middle of a byte, we have failed to
5249 comply with the ABI. */
5251 && DECL_C_BIT_FIELD (field)
5252 /* The TREE_NO_WARNING flag gets set by Objective-C when
5253 laying out an Objective-C class. The ObjC ABI differs
5254 from the C++ ABI, and so we do not want a warning
5256 && !TREE_NO_WARNING (field)
5257 && !last_field_was_bitfield
5258 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5259 DECL_FIELD_BIT_OFFSET (field),
5260 bitsize_unit_node)))
5261 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5262 "change in a future version of GCC", field);
5264 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5265 offset of the field. */
5267 && !abi_version_at_least (2)
5268 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5269 byte_position (field))
5270 && contains_empty_class_p (TREE_TYPE (field)))
5271 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5272 "classes to be placed at different locations in a "
5273 "future version of GCC", field);
5275 /* The middle end uses the type of expressions to determine the
5276 possible range of expression values. In order to optimize
5277 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5278 must be made aware of the width of "i", via its type.
5280 Because C++ does not have integer types of arbitrary width,
5281 we must (for the purposes of the front end) convert from the
5282 type assigned here to the declared type of the bitfield
5283 whenever a bitfield expression is used as an rvalue.
5284 Similarly, when assigning a value to a bitfield, the value
5285 must be converted to the type given the bitfield here. */
5286 if (DECL_C_BIT_FIELD (field))
5288 unsigned HOST_WIDE_INT width;
5289 tree ftype = TREE_TYPE (field);
5290 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5291 if (width != TYPE_PRECISION (ftype))
5294 = c_build_bitfield_integer_type (width,
5295 TYPE_UNSIGNED (ftype));
5297 = cp_build_qualified_type (TREE_TYPE (field),
5298 cp_type_quals (ftype));
5302 /* If we needed additional padding after this field, add it
5308 padding_field = build_decl (input_location,
5312 DECL_BIT_FIELD (padding_field) = 1;
5313 DECL_SIZE (padding_field) = padding;
5314 DECL_CONTEXT (padding_field) = t;
5315 DECL_ARTIFICIAL (padding_field) = 1;
5316 DECL_IGNORED_P (padding_field) = 1;
5317 layout_nonempty_base_or_field (rli, padding_field,
5319 empty_base_offsets);
5322 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5325 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5327 /* Make sure that we are on a byte boundary so that the size of
5328 the class without virtual bases will always be a round number
5330 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5331 normalize_rli (rli);
5334 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5336 if (!abi_version_at_least (2))
5337 include_empty_classes(rli);
5339 /* Delete all zero-width bit-fields from the list of fields. Now
5340 that the type is laid out they are no longer important. */
5341 remove_zero_width_bit_fields (t);
5343 /* Create the version of T used for virtual bases. We do not use
5344 make_class_type for this version; this is an artificial type. For
5345 a POD type, we just reuse T. */
5346 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5348 base_t = make_node (TREE_CODE (t));
5350 /* Set the size and alignment for the new type. In G++ 3.2, all
5351 empty classes were considered to have size zero when used as
5353 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5355 TYPE_SIZE (base_t) = bitsize_zero_node;
5356 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5357 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5359 "layout of classes derived from empty class %qT "
5360 "may change in a future version of GCC",
5367 /* If the ABI version is not at least two, and the last
5368 field was a bit-field, RLI may not be on a byte
5369 boundary. In particular, rli_size_unit_so_far might
5370 indicate the last complete byte, while rli_size_so_far
5371 indicates the total number of bits used. Therefore,
5372 rli_size_so_far, rather than rli_size_unit_so_far, is
5373 used to compute TYPE_SIZE_UNIT. */
5374 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5375 TYPE_SIZE_UNIT (base_t)
5376 = size_binop (MAX_EXPR,
5378 size_binop (CEIL_DIV_EXPR,
5379 rli_size_so_far (rli),
5380 bitsize_int (BITS_PER_UNIT))),
5383 = size_binop (MAX_EXPR,
5384 rli_size_so_far (rli),
5385 size_binop (MULT_EXPR,
5386 convert (bitsizetype, eoc),
5387 bitsize_int (BITS_PER_UNIT)));
5389 TYPE_ALIGN (base_t) = rli->record_align;
5390 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5392 /* Copy the fields from T. */
5393 next_field = &TYPE_FIELDS (base_t);
5394 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5395 if (TREE_CODE (field) == FIELD_DECL)
5397 *next_field = build_decl (input_location,
5401 DECL_CONTEXT (*next_field) = base_t;
5402 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5403 DECL_FIELD_BIT_OFFSET (*next_field)
5404 = DECL_FIELD_BIT_OFFSET (field);
5405 DECL_SIZE (*next_field) = DECL_SIZE (field);
5406 DECL_MODE (*next_field) = DECL_MODE (field);
5407 next_field = &DECL_CHAIN (*next_field);
5410 /* Record the base version of the type. */
5411 CLASSTYPE_AS_BASE (t) = base_t;
5412 TYPE_CONTEXT (base_t) = t;
5415 CLASSTYPE_AS_BASE (t) = t;
5417 /* Every empty class contains an empty class. */
5418 if (CLASSTYPE_EMPTY_P (t))
5419 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5421 /* Set the TYPE_DECL for this type to contain the right
5422 value for DECL_OFFSET, so that we can use it as part
5423 of a COMPONENT_REF for multiple inheritance. */
5424 layout_decl (TYPE_MAIN_DECL (t), 0);
5426 /* Now fix up any virtual base class types that we left lying
5427 around. We must get these done before we try to lay out the
5428 virtual function table. As a side-effect, this will remove the
5429 base subobject fields. */
5430 layout_virtual_bases (rli, empty_base_offsets);
5432 /* Make sure that empty classes are reflected in RLI at this
5434 include_empty_classes(rli);
5436 /* Make sure not to create any structures with zero size. */
5437 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5439 build_decl (input_location,
5440 FIELD_DECL, NULL_TREE, char_type_node));
5442 /* If this is a non-POD, declaring it packed makes a difference to how it
5443 can be used as a field; don't let finalize_record_size undo it. */
5444 if (TYPE_PACKED (t) && !layout_pod_type_p (t))
5445 rli->packed_maybe_necessary = true;
5447 /* Let the back end lay out the type. */
5448 finish_record_layout (rli, /*free_p=*/true);
5450 /* Warn about bases that can't be talked about due to ambiguity. */
5451 warn_about_ambiguous_bases (t);
5453 /* Now that we're done with layout, give the base fields the real types. */
5454 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5455 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5456 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5459 splay_tree_delete (empty_base_offsets);
5461 if (CLASSTYPE_EMPTY_P (t)
5462 && tree_int_cst_lt (sizeof_biggest_empty_class,
5463 TYPE_SIZE_UNIT (t)))
5464 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5467 /* Determine the "key method" for the class type indicated by TYPE,
5468 and set CLASSTYPE_KEY_METHOD accordingly. */
5471 determine_key_method (tree type)
5475 if (TYPE_FOR_JAVA (type)
5476 || processing_template_decl
5477 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5478 || CLASSTYPE_INTERFACE_KNOWN (type))
5481 /* The key method is the first non-pure virtual function that is not
5482 inline at the point of class definition. On some targets the
5483 key function may not be inline; those targets should not call
5484 this function until the end of the translation unit. */
5485 for (method = TYPE_METHODS (type); method != NULL_TREE;
5486 method = DECL_CHAIN (method))
5487 if (DECL_VINDEX (method) != NULL_TREE
5488 && ! DECL_DECLARED_INLINE_P (method)
5489 && ! DECL_PURE_VIRTUAL_P (method))
5491 CLASSTYPE_KEY_METHOD (type) = method;
5498 /* Perform processing required when the definition of T (a class type)
5502 finish_struct_1 (tree t)
5505 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5506 tree virtuals = NULL_TREE;
5509 if (COMPLETE_TYPE_P (t))
5511 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5512 error ("redefinition of %q#T", t);
5517 /* If this type was previously laid out as a forward reference,
5518 make sure we lay it out again. */
5519 TYPE_SIZE (t) = NULL_TREE;
5520 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5522 /* Make assumptions about the class; we'll reset the flags if
5524 CLASSTYPE_EMPTY_P (t) = 1;
5525 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5526 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5527 CLASSTYPE_LITERAL_P (t) = true;
5529 /* Do end-of-class semantic processing: checking the validity of the
5530 bases and members and add implicitly generated methods. */
5531 check_bases_and_members (t);
5533 /* Find the key method. */
5534 if (TYPE_CONTAINS_VPTR_P (t))
5536 /* The Itanium C++ ABI permits the key method to be chosen when
5537 the class is defined -- even though the key method so
5538 selected may later turn out to be an inline function. On
5539 some systems (such as ARM Symbian OS) the key method cannot
5540 be determined until the end of the translation unit. On such
5541 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5542 will cause the class to be added to KEYED_CLASSES. Then, in
5543 finish_file we will determine the key method. */
5544 if (targetm.cxx.key_method_may_be_inline ())
5545 determine_key_method (t);
5547 /* If a polymorphic class has no key method, we may emit the vtable
5548 in every translation unit where the class definition appears. */
5549 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5550 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5553 /* Layout the class itself. */
5554 layout_class_type (t, &virtuals);
5555 if (CLASSTYPE_AS_BASE (t) != t)
5556 /* We use the base type for trivial assignments, and hence it
5558 compute_record_mode (CLASSTYPE_AS_BASE (t));
5560 virtuals = modify_all_vtables (t, nreverse (virtuals));
5562 /* If necessary, create the primary vtable for this class. */
5563 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5565 /* We must enter these virtuals into the table. */
5566 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5567 build_primary_vtable (NULL_TREE, t);
5568 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5569 /* Here we know enough to change the type of our virtual
5570 function table, but we will wait until later this function. */
5571 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5574 if (TYPE_CONTAINS_VPTR_P (t))
5579 if (BINFO_VTABLE (TYPE_BINFO (t)))
5580 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5581 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5582 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5584 /* Add entries for virtual functions introduced by this class. */
5585 BINFO_VIRTUALS (TYPE_BINFO (t))
5586 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5588 /* Set DECL_VINDEX for all functions declared in this class. */
5589 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5591 fn = TREE_CHAIN (fn),
5592 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5593 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5595 tree fndecl = BV_FN (fn);
5597 if (DECL_THUNK_P (fndecl))
5598 /* A thunk. We should never be calling this entry directly
5599 from this vtable -- we'd use the entry for the non
5600 thunk base function. */
5601 DECL_VINDEX (fndecl) = NULL_TREE;
5602 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5603 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5607 finish_struct_bits (t);
5609 /* Complete the rtl for any static member objects of the type we're
5611 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
5612 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5613 && TREE_TYPE (x) != error_mark_node
5614 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5615 DECL_MODE (x) = TYPE_MODE (t);
5617 /* Done with FIELDS...now decide whether to sort these for
5618 faster lookups later.
5620 We use a small number because most searches fail (succeeding
5621 ultimately as the search bores through the inheritance
5622 hierarchy), and we want this failure to occur quickly. */
5624 n_fields = count_fields (TYPE_FIELDS (t));
5627 struct sorted_fields_type *field_vec = ggc_alloc_sorted_fields_type
5628 (sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5629 field_vec->len = n_fields;
5630 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5631 qsort (field_vec->elts, n_fields, sizeof (tree),
5633 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
5636 /* Complain if one of the field types requires lower visibility. */
5637 constrain_class_visibility (t);
5639 /* Make the rtl for any new vtables we have created, and unmark
5640 the base types we marked. */
5643 /* Build the VTT for T. */
5646 /* This warning does not make sense for Java classes, since they
5647 cannot have destructors. */
5648 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5652 dtor = CLASSTYPE_DESTRUCTORS (t);
5653 if (/* An implicitly declared destructor is always public. And,
5654 if it were virtual, we would have created it by now. */
5656 || (!DECL_VINDEX (dtor)
5657 && (/* public non-virtual */
5658 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5659 || (/* non-public non-virtual with friends */
5660 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5661 && (CLASSTYPE_FRIEND_CLASSES (t)
5662 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5663 warning (OPT_Wnon_virtual_dtor,
5664 "%q#T has virtual functions and accessible"
5665 " non-virtual destructor", t);
5670 if (warn_overloaded_virtual)
5673 /* Class layout, assignment of virtual table slots, etc., is now
5674 complete. Give the back end a chance to tweak the visibility of
5675 the class or perform any other required target modifications. */
5676 targetm.cxx.adjust_class_at_definition (t);
5678 maybe_suppress_debug_info (t);
5680 dump_class_hierarchy (t);
5682 /* Finish debugging output for this type. */
5683 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5686 /* When T was built up, the member declarations were added in reverse
5687 order. Rearrange them to declaration order. */
5690 unreverse_member_declarations (tree t)
5696 /* The following lists are all in reverse order. Put them in
5697 declaration order now. */
5698 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5699 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5701 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5702 reverse order, so we can't just use nreverse. */
5704 for (x = TYPE_FIELDS (t);
5705 x && TREE_CODE (x) != TYPE_DECL;
5708 next = DECL_CHAIN (x);
5709 DECL_CHAIN (x) = prev;
5714 DECL_CHAIN (TYPE_FIELDS (t)) = x;
5716 TYPE_FIELDS (t) = prev;
5721 finish_struct (tree t, tree attributes)
5723 location_t saved_loc = input_location;
5725 /* Now that we've got all the field declarations, reverse everything
5727 unreverse_member_declarations (t);
5729 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5731 /* Nadger the current location so that diagnostics point to the start of
5732 the struct, not the end. */
5733 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5735 if (processing_template_decl)
5739 finish_struct_methods (t);
5740 TYPE_SIZE (t) = bitsize_zero_node;
5741 TYPE_SIZE_UNIT (t) = size_zero_node;
5743 /* We need to emit an error message if this type was used as a parameter
5744 and it is an abstract type, even if it is a template. We construct
5745 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5746 account and we call complete_vars with this type, which will check
5747 the PARM_DECLS. Note that while the type is being defined,
5748 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5749 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5750 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5751 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
5752 if (DECL_PURE_VIRTUAL_P (x))
5753 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5756 /* Remember current #pragma pack value. */
5757 TYPE_PRECISION (t) = maximum_field_alignment;
5760 finish_struct_1 (t);
5762 input_location = saved_loc;
5764 TYPE_BEING_DEFINED (t) = 0;
5766 if (current_class_type)
5769 error ("trying to finish struct, but kicked out due to previous parse errors");
5771 if (processing_template_decl && at_function_scope_p ())
5772 add_stmt (build_min (TAG_DEFN, t));
5777 /* Return the dynamic type of INSTANCE, if known.
5778 Used to determine whether the virtual function table is needed
5781 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5782 of our knowledge of its type. *NONNULL should be initialized
5783 before this function is called. */
5786 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5788 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5790 switch (TREE_CODE (instance))
5793 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5796 return RECUR (TREE_OPERAND (instance, 0));
5799 /* This is a call to a constructor, hence it's never zero. */
5800 if (TREE_HAS_CONSTRUCTOR (instance))
5804 return TREE_TYPE (instance);
5809 /* This is a call to a constructor, hence it's never zero. */
5810 if (TREE_HAS_CONSTRUCTOR (instance))
5814 return TREE_TYPE (instance);
5816 return RECUR (TREE_OPERAND (instance, 0));
5818 case POINTER_PLUS_EXPR:
5821 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5822 return RECUR (TREE_OPERAND (instance, 0));
5823 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5824 /* Propagate nonnull. */
5825 return RECUR (TREE_OPERAND (instance, 0));
5830 return RECUR (TREE_OPERAND (instance, 0));
5833 instance = TREE_OPERAND (instance, 0);
5836 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5837 with a real object -- given &p->f, p can still be null. */
5838 tree t = get_base_address (instance);
5839 /* ??? Probably should check DECL_WEAK here. */
5840 if (t && DECL_P (t))
5843 return RECUR (instance);
5846 /* If this component is really a base class reference, then the field
5847 itself isn't definitive. */
5848 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5849 return RECUR (TREE_OPERAND (instance, 0));
5850 return RECUR (TREE_OPERAND (instance, 1));
5854 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5855 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
5859 return TREE_TYPE (TREE_TYPE (instance));
5861 /* fall through... */
5865 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
5869 return TREE_TYPE (instance);
5871 else if (instance == current_class_ptr)
5876 /* if we're in a ctor or dtor, we know our type. */
5877 if (DECL_LANG_SPECIFIC (current_function_decl)
5878 && (DECL_CONSTRUCTOR_P (current_function_decl)
5879 || DECL_DESTRUCTOR_P (current_function_decl)))
5883 return TREE_TYPE (TREE_TYPE (instance));
5886 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5888 /* We only need one hash table because it is always left empty. */
5891 ht = htab_create (37,
5896 /* Reference variables should be references to objects. */
5900 /* Enter the INSTANCE in a table to prevent recursion; a
5901 variable's initializer may refer to the variable
5903 if (TREE_CODE (instance) == VAR_DECL
5904 && DECL_INITIAL (instance)
5905 && !htab_find (ht, instance))
5910 slot = htab_find_slot (ht, instance, INSERT);
5912 type = RECUR (DECL_INITIAL (instance));
5913 htab_remove_elt (ht, instance);
5926 /* Return nonzero if the dynamic type of INSTANCE is known, and
5927 equivalent to the static type. We also handle the case where
5928 INSTANCE is really a pointer. Return negative if this is a
5929 ctor/dtor. There the dynamic type is known, but this might not be
5930 the most derived base of the original object, and hence virtual
5931 bases may not be layed out according to this type.
5933 Used to determine whether the virtual function table is needed
5936 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5937 of our knowledge of its type. *NONNULL should be initialized
5938 before this function is called. */
5941 resolves_to_fixed_type_p (tree instance, int* nonnull)
5943 tree t = TREE_TYPE (instance);
5945 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5946 if (fixed == NULL_TREE)
5948 if (POINTER_TYPE_P (t))
5950 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5952 return cdtorp ? -1 : 1;
5957 init_class_processing (void)
5959 current_class_depth = 0;
5960 current_class_stack_size = 10;
5962 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5963 local_classes = VEC_alloc (tree, gc, 8);
5964 sizeof_biggest_empty_class = size_zero_node;
5966 ridpointers[(int) RID_PUBLIC] = access_public_node;
5967 ridpointers[(int) RID_PRIVATE] = access_private_node;
5968 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5971 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5974 restore_class_cache (void)
5978 /* We are re-entering the same class we just left, so we don't
5979 have to search the whole inheritance matrix to find all the
5980 decls to bind again. Instead, we install the cached
5981 class_shadowed list and walk through it binding names. */
5982 push_binding_level (previous_class_level);
5983 class_binding_level = previous_class_level;
5984 /* Restore IDENTIFIER_TYPE_VALUE. */
5985 for (type = class_binding_level->type_shadowed;
5987 type = TREE_CHAIN (type))
5988 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5991 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5992 appropriate for TYPE.
5994 So that we may avoid calls to lookup_name, we cache the _TYPE
5995 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5997 For multiple inheritance, we perform a two-pass depth-first search
5998 of the type lattice. */
6001 pushclass (tree type)
6003 class_stack_node_t csn;
6005 type = TYPE_MAIN_VARIANT (type);
6007 /* Make sure there is enough room for the new entry on the stack. */
6008 if (current_class_depth + 1 >= current_class_stack_size)
6010 current_class_stack_size *= 2;
6012 = XRESIZEVEC (struct class_stack_node, current_class_stack,
6013 current_class_stack_size);
6016 /* Insert a new entry on the class stack. */
6017 csn = current_class_stack + current_class_depth;
6018 csn->name = current_class_name;
6019 csn->type = current_class_type;
6020 csn->access = current_access_specifier;
6021 csn->names_used = 0;
6023 current_class_depth++;
6025 /* Now set up the new type. */
6026 current_class_name = TYPE_NAME (type);
6027 if (TREE_CODE (current_class_name) == TYPE_DECL)
6028 current_class_name = DECL_NAME (current_class_name);
6029 current_class_type = type;
6031 /* By default, things in classes are private, while things in
6032 structures or unions are public. */
6033 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
6034 ? access_private_node
6035 : access_public_node);
6037 if (previous_class_level
6038 && type != previous_class_level->this_entity
6039 && current_class_depth == 1)
6041 /* Forcibly remove any old class remnants. */
6042 invalidate_class_lookup_cache ();
6045 if (!previous_class_level
6046 || type != previous_class_level->this_entity
6047 || current_class_depth > 1)
6050 restore_class_cache ();
6053 /* When we exit a toplevel class scope, we save its binding level so
6054 that we can restore it quickly. Here, we've entered some other
6055 class, so we must invalidate our cache. */
6058 invalidate_class_lookup_cache (void)
6060 previous_class_level = NULL;
6063 /* Get out of the current class scope. If we were in a class scope
6064 previously, that is the one popped to. */
6071 current_class_depth--;
6072 current_class_name = current_class_stack[current_class_depth].name;
6073 current_class_type = current_class_stack[current_class_depth].type;
6074 current_access_specifier = current_class_stack[current_class_depth].access;
6075 if (current_class_stack[current_class_depth].names_used)
6076 splay_tree_delete (current_class_stack[current_class_depth].names_used);
6079 /* Mark the top of the class stack as hidden. */
6082 push_class_stack (void)
6084 if (current_class_depth)
6085 ++current_class_stack[current_class_depth - 1].hidden;
6088 /* Mark the top of the class stack as un-hidden. */
6091 pop_class_stack (void)
6093 if (current_class_depth)
6094 --current_class_stack[current_class_depth - 1].hidden;
6097 /* Returns 1 if the class type currently being defined is either T or
6098 a nested type of T. */
6101 currently_open_class (tree t)
6105 if (!CLASS_TYPE_P (t))
6108 t = TYPE_MAIN_VARIANT (t);
6110 /* We start looking from 1 because entry 0 is from global scope,
6112 for (i = current_class_depth; i > 0; --i)
6115 if (i == current_class_depth)
6116 c = current_class_type;
6119 if (current_class_stack[i].hidden)
6121 c = current_class_stack[i].type;
6125 if (same_type_p (c, t))
6131 /* If either current_class_type or one of its enclosing classes are derived
6132 from T, return the appropriate type. Used to determine how we found
6133 something via unqualified lookup. */
6136 currently_open_derived_class (tree t)
6140 /* The bases of a dependent type are unknown. */
6141 if (dependent_type_p (t))
6144 if (!current_class_type)
6147 if (DERIVED_FROM_P (t, current_class_type))
6148 return current_class_type;
6150 for (i = current_class_depth - 1; i > 0; --i)
6152 if (current_class_stack[i].hidden)
6154 if (DERIVED_FROM_P (t, current_class_stack[i].type))
6155 return current_class_stack[i].type;
6161 /* Returns the innermost class type which is not a lambda closure type. */
6164 current_nonlambda_class_type (void)
6168 /* We start looking from 1 because entry 0 is from global scope,
6170 for (i = current_class_depth; i > 0; --i)
6173 if (i == current_class_depth)
6174 c = current_class_type;
6177 if (current_class_stack[i].hidden)
6179 c = current_class_stack[i].type;
6183 if (!LAMBDA_TYPE_P (c))
6189 /* When entering a class scope, all enclosing class scopes' names with
6190 static meaning (static variables, static functions, types and
6191 enumerators) have to be visible. This recursive function calls
6192 pushclass for all enclosing class contexts until global or a local
6193 scope is reached. TYPE is the enclosed class. */
6196 push_nested_class (tree type)
6198 /* A namespace might be passed in error cases, like A::B:C. */
6199 if (type == NULL_TREE
6200 || !CLASS_TYPE_P (type))
6203 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
6208 /* Undoes a push_nested_class call. */
6211 pop_nested_class (void)
6213 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
6216 if (context && CLASS_TYPE_P (context))
6217 pop_nested_class ();
6220 /* Returns the number of extern "LANG" blocks we are nested within. */
6223 current_lang_depth (void)
6225 return VEC_length (tree, current_lang_base);
6228 /* Set global variables CURRENT_LANG_NAME to appropriate value
6229 so that behavior of name-mangling machinery is correct. */
6232 push_lang_context (tree name)
6234 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
6236 if (name == lang_name_cplusplus)
6238 current_lang_name = name;
6240 else if (name == lang_name_java)
6242 current_lang_name = name;
6243 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6244 (See record_builtin_java_type in decl.c.) However, that causes
6245 incorrect debug entries if these types are actually used.
6246 So we re-enable debug output after extern "Java". */
6247 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
6248 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
6249 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
6250 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
6251 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
6252 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
6253 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
6254 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
6256 else if (name == lang_name_c)
6258 current_lang_name = name;
6261 error ("language string %<\"%E\"%> not recognized", name);
6264 /* Get out of the current language scope. */
6267 pop_lang_context (void)
6269 current_lang_name = VEC_pop (tree, current_lang_base);
6272 /* Type instantiation routines. */
6274 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6275 matches the TARGET_TYPE. If there is no satisfactory match, return
6276 error_mark_node, and issue an error & warning messages under
6277 control of FLAGS. Permit pointers to member function if FLAGS
6278 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6279 a template-id, and EXPLICIT_TARGS are the explicitly provided
6282 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6283 is the base path used to reference those member functions. If
6284 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6285 resolved to a member function, access checks will be performed and
6286 errors issued if appropriate. */
6289 resolve_address_of_overloaded_function (tree target_type,
6291 tsubst_flags_t flags,
6293 tree explicit_targs,
6296 /* Here's what the standard says:
6300 If the name is a function template, template argument deduction
6301 is done, and if the argument deduction succeeds, the deduced
6302 arguments are used to generate a single template function, which
6303 is added to the set of overloaded functions considered.
6305 Non-member functions and static member functions match targets of
6306 type "pointer-to-function" or "reference-to-function." Nonstatic
6307 member functions match targets of type "pointer-to-member
6308 function;" the function type of the pointer to member is used to
6309 select the member function from the set of overloaded member
6310 functions. If a nonstatic member function is selected, the
6311 reference to the overloaded function name is required to have the
6312 form of a pointer to member as described in 5.3.1.
6314 If more than one function is selected, any template functions in
6315 the set are eliminated if the set also contains a non-template
6316 function, and any given template function is eliminated if the
6317 set contains a second template function that is more specialized
6318 than the first according to the partial ordering rules 14.5.5.2.
6319 After such eliminations, if any, there shall remain exactly one
6320 selected function. */
6323 /* We store the matches in a TREE_LIST rooted here. The functions
6324 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6325 interoperability with most_specialized_instantiation. */
6326 tree matches = NULL_TREE;
6328 tree target_fn_type;
6330 /* By the time we get here, we should be seeing only real
6331 pointer-to-member types, not the internal POINTER_TYPE to
6332 METHOD_TYPE representation. */
6333 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6334 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6336 gcc_assert (is_overloaded_fn (overload));
6338 /* Check that the TARGET_TYPE is reasonable. */
6339 if (TYPE_PTRFN_P (target_type))
6341 else if (TYPE_PTRMEMFUNC_P (target_type))
6342 /* This is OK, too. */
6344 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6345 /* This is OK, too. This comes from a conversion to reference
6347 target_type = build_reference_type (target_type);
6350 if (flags & tf_error)
6351 error ("cannot resolve overloaded function %qD based on"
6352 " conversion to type %qT",
6353 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6354 return error_mark_node;
6357 /* Non-member functions and static member functions match targets of type
6358 "pointer-to-function" or "reference-to-function." Nonstatic member
6359 functions match targets of type "pointer-to-member-function;" the
6360 function type of the pointer to member is used to select the member
6361 function from the set of overloaded member functions.
6363 So figure out the FUNCTION_TYPE that we want to match against. */
6364 target_fn_type = static_fn_type (target_type);
6366 /* If we can find a non-template function that matches, we can just
6367 use it. There's no point in generating template instantiations
6368 if we're just going to throw them out anyhow. But, of course, we
6369 can only do this when we don't *need* a template function. */
6374 for (fns = overload; fns; fns = OVL_NEXT (fns))
6376 tree fn = OVL_CURRENT (fns);
6378 if (TREE_CODE (fn) == TEMPLATE_DECL)
6379 /* We're not looking for templates just yet. */
6382 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6384 /* We're looking for a non-static member, and this isn't
6385 one, or vice versa. */
6388 /* Ignore functions which haven't been explicitly
6390 if (DECL_ANTICIPATED (fn))
6393 /* See if there's a match. */
6394 if (same_type_p (target_fn_type, static_fn_type (fn)))
6395 matches = tree_cons (fn, NULL_TREE, matches);
6399 /* Now, if we've already got a match (or matches), there's no need
6400 to proceed to the template functions. But, if we don't have a
6401 match we need to look at them, too. */
6404 tree target_arg_types;
6405 tree target_ret_type;
6408 unsigned int nargs, ia;
6411 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6412 target_ret_type = TREE_TYPE (target_fn_type);
6414 nargs = list_length (target_arg_types);
6415 args = XALLOCAVEC (tree, nargs);
6416 for (arg = target_arg_types, ia = 0;
6417 arg != NULL_TREE && arg != void_list_node;
6418 arg = TREE_CHAIN (arg), ++ia)
6419 args[ia] = TREE_VALUE (arg);
6422 for (fns = overload; fns; fns = OVL_NEXT (fns))
6424 tree fn = OVL_CURRENT (fns);
6428 if (TREE_CODE (fn) != TEMPLATE_DECL)
6429 /* We're only looking for templates. */
6432 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6434 /* We're not looking for a non-static member, and this is
6435 one, or vice versa. */
6438 /* Try to do argument deduction. */
6439 targs = make_tree_vec (DECL_NTPARMS (fn));
6440 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6441 target_ret_type, DEDUCE_EXACT,
6443 /* Argument deduction failed. */
6446 /* Instantiate the template. */
6447 instantiation = instantiate_template (fn, targs, flags);
6448 if (instantiation == error_mark_node)
6449 /* Instantiation failed. */
6452 /* See if there's a match. */
6453 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
6454 matches = tree_cons (instantiation, fn, matches);
6457 /* Now, remove all but the most specialized of the matches. */
6460 tree match = most_specialized_instantiation (matches);
6462 if (match != error_mark_node)
6463 matches = tree_cons (TREE_PURPOSE (match),
6469 /* Now we should have exactly one function in MATCHES. */
6470 if (matches == NULL_TREE)
6472 /* There were *no* matches. */
6473 if (flags & tf_error)
6475 error ("no matches converting function %qD to type %q#T",
6476 DECL_NAME (OVL_CURRENT (overload)),
6479 /* print_candidates expects a chain with the functions in
6480 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6481 so why be clever?). */
6482 for (; overload; overload = OVL_NEXT (overload))
6483 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
6486 print_candidates (matches);
6488 return error_mark_node;
6490 else if (TREE_CHAIN (matches))
6492 /* There were too many matches. First check if they're all
6493 the same function. */
6496 fn = TREE_PURPOSE (matches);
6497 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6498 if (!decls_match (fn, TREE_PURPOSE (match)))
6503 if (flags & tf_error)
6505 error ("converting overloaded function %qD to type %q#T is ambiguous",
6506 DECL_NAME (OVL_FUNCTION (overload)),
6509 /* Since print_candidates expects the functions in the
6510 TREE_VALUE slot, we flip them here. */
6511 for (match = matches; match; match = TREE_CHAIN (match))
6512 TREE_VALUE (match) = TREE_PURPOSE (match);
6514 print_candidates (matches);
6517 return error_mark_node;
6521 /* Good, exactly one match. Now, convert it to the correct type. */
6522 fn = TREE_PURPOSE (matches);
6524 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6525 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6527 static int explained;
6529 if (!(flags & tf_error))
6530 return error_mark_node;
6532 permerror (input_location, "assuming pointer to member %qD", fn);
6535 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6540 /* If we're doing overload resolution purely for the purpose of
6541 determining conversion sequences, we should not consider the
6542 function used. If this conversion sequence is selected, the
6543 function will be marked as used at this point. */
6544 if (!(flags & tf_conv))
6546 /* Make =delete work with SFINAE. */
6547 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6548 return error_mark_node;
6553 /* We could not check access to member functions when this
6554 expression was originally created since we did not know at that
6555 time to which function the expression referred. */
6556 if (!(flags & tf_no_access_control)
6557 && DECL_FUNCTION_MEMBER_P (fn))
6559 gcc_assert (access_path);
6560 perform_or_defer_access_check (access_path, fn, fn);
6563 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6564 return cp_build_addr_expr (fn, flags);
6567 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6568 will mark the function as addressed, but here we must do it
6570 cxx_mark_addressable (fn);
6576 /* This function will instantiate the type of the expression given in
6577 RHS to match the type of LHSTYPE. If errors exist, then return
6578 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6579 we complain on errors. If we are not complaining, never modify rhs,
6580 as overload resolution wants to try many possible instantiations, in
6581 the hope that at least one will work.
6583 For non-recursive calls, LHSTYPE should be a function, pointer to
6584 function, or a pointer to member function. */
6587 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6589 tsubst_flags_t flags_in = flags;
6590 tree access_path = NULL_TREE;
6592 flags &= ~tf_ptrmem_ok;
6594 if (lhstype == unknown_type_node)
6596 if (flags & tf_error)
6597 error ("not enough type information");
6598 return error_mark_node;
6601 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6603 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6605 if (flag_ms_extensions
6606 && TYPE_PTRMEMFUNC_P (lhstype)
6607 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6608 /* Microsoft allows `A::f' to be resolved to a
6609 pointer-to-member. */
6613 if (flags & tf_error)
6614 error ("argument of type %qT does not match %qT",
6615 TREE_TYPE (rhs), lhstype);
6616 return error_mark_node;
6620 if (TREE_CODE (rhs) == BASELINK)
6622 access_path = BASELINK_ACCESS_BINFO (rhs);
6623 rhs = BASELINK_FUNCTIONS (rhs);
6626 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6627 deduce any type information. */
6628 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6630 if (flags & tf_error)
6631 error ("not enough type information");
6632 return error_mark_node;
6635 /* There only a few kinds of expressions that may have a type
6636 dependent on overload resolution. */
6637 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6638 || TREE_CODE (rhs) == COMPONENT_REF
6639 || really_overloaded_fn (rhs)
6640 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
6642 /* This should really only be used when attempting to distinguish
6643 what sort of a pointer to function we have. For now, any
6644 arithmetic operation which is not supported on pointers
6645 is rejected as an error. */
6647 switch (TREE_CODE (rhs))
6651 tree member = TREE_OPERAND (rhs, 1);
6653 member = instantiate_type (lhstype, member, flags);
6654 if (member != error_mark_node
6655 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6656 /* Do not lose object's side effects. */
6657 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6658 TREE_OPERAND (rhs, 0), member);
6663 rhs = TREE_OPERAND (rhs, 1);
6664 if (BASELINK_P (rhs))
6665 return instantiate_type (lhstype, rhs, flags_in);
6667 /* This can happen if we are forming a pointer-to-member for a
6669 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6673 case TEMPLATE_ID_EXPR:
6675 tree fns = TREE_OPERAND (rhs, 0);
6676 tree args = TREE_OPERAND (rhs, 1);
6679 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6680 /*template_only=*/true,
6687 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6688 /*template_only=*/false,
6689 /*explicit_targs=*/NULL_TREE,
6694 if (PTRMEM_OK_P (rhs))
6695 flags |= tf_ptrmem_ok;
6697 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6701 return error_mark_node;
6706 return error_mark_node;
6709 /* Return the name of the virtual function pointer field
6710 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6711 this may have to look back through base types to find the
6712 ultimate field name. (For single inheritance, these could
6713 all be the same name. Who knows for multiple inheritance). */
6716 get_vfield_name (tree type)
6718 tree binfo, base_binfo;
6721 for (binfo = TYPE_BINFO (type);
6722 BINFO_N_BASE_BINFOS (binfo);
6725 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6727 if (BINFO_VIRTUAL_P (base_binfo)
6728 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6732 type = BINFO_TYPE (binfo);
6733 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6734 + TYPE_NAME_LENGTH (type) + 2);
6735 sprintf (buf, VFIELD_NAME_FORMAT,
6736 IDENTIFIER_POINTER (constructor_name (type)));
6737 return get_identifier (buf);
6741 print_class_statistics (void)
6743 #ifdef GATHER_STATISTICS
6744 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6745 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6748 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6749 n_vtables, n_vtable_searches);
6750 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6751 n_vtable_entries, n_vtable_elems);
6756 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6757 according to [class]:
6758 The class-name is also inserted
6759 into the scope of the class itself. For purposes of access checking,
6760 the inserted class name is treated as if it were a public member name. */
6763 build_self_reference (void)
6765 tree name = constructor_name (current_class_type);
6766 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6769 DECL_NONLOCAL (value) = 1;
6770 DECL_CONTEXT (value) = current_class_type;
6771 DECL_ARTIFICIAL (value) = 1;
6772 SET_DECL_SELF_REFERENCE_P (value);
6773 set_underlying_type (value);
6775 if (processing_template_decl)
6776 value = push_template_decl (value);
6778 saved_cas = current_access_specifier;
6779 current_access_specifier = access_public_node;
6780 finish_member_declaration (value);
6781 current_access_specifier = saved_cas;
6784 /* Returns 1 if TYPE contains only padding bytes. */
6787 is_empty_class (tree type)
6789 if (type == error_mark_node)
6792 if (! CLASS_TYPE_P (type))
6795 /* In G++ 3.2, whether or not a class was empty was determined by
6796 looking at its size. */
6797 if (abi_version_at_least (2))
6798 return CLASSTYPE_EMPTY_P (type);
6800 return integer_zerop (CLASSTYPE_SIZE (type));
6803 /* Returns true if TYPE contains an empty class. */
6806 contains_empty_class_p (tree type)
6808 if (is_empty_class (type))
6810 if (CLASS_TYPE_P (type))
6817 for (binfo = TYPE_BINFO (type), i = 0;
6818 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6819 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6821 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6822 if (TREE_CODE (field) == FIELD_DECL
6823 && !DECL_ARTIFICIAL (field)
6824 && is_empty_class (TREE_TYPE (field)))
6827 else if (TREE_CODE (type) == ARRAY_TYPE)
6828 return contains_empty_class_p (TREE_TYPE (type));
6832 /* Returns true if TYPE contains no actual data, just various
6833 possible combinations of empty classes and possibly a vptr. */
6836 is_really_empty_class (tree type)
6838 if (CLASS_TYPE_P (type))
6845 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
6846 out, but we'd like to be able to check this before then. */
6847 if (COMPLETE_TYPE_P (type) && is_empty_class (type))
6850 for (binfo = TYPE_BINFO (type), i = 0;
6851 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6852 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
6854 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
6855 if (TREE_CODE (field) == FIELD_DECL
6856 && !DECL_ARTIFICIAL (field)
6857 && !is_really_empty_class (TREE_TYPE (field)))
6861 else if (TREE_CODE (type) == ARRAY_TYPE)
6862 return is_really_empty_class (TREE_TYPE (type));
6866 /* Note that NAME was looked up while the current class was being
6867 defined and that the result of that lookup was DECL. */
6870 maybe_note_name_used_in_class (tree name, tree decl)
6872 splay_tree names_used;
6874 /* If we're not defining a class, there's nothing to do. */
6875 if (!(innermost_scope_kind() == sk_class
6876 && TYPE_BEING_DEFINED (current_class_type)
6877 && !LAMBDA_TYPE_P (current_class_type)))
6880 /* If there's already a binding for this NAME, then we don't have
6881 anything to worry about. */
6882 if (lookup_member (current_class_type, name,
6883 /*protect=*/0, /*want_type=*/false))
6886 if (!current_class_stack[current_class_depth - 1].names_used)
6887 current_class_stack[current_class_depth - 1].names_used
6888 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6889 names_used = current_class_stack[current_class_depth - 1].names_used;
6891 splay_tree_insert (names_used,
6892 (splay_tree_key) name,
6893 (splay_tree_value) decl);
6896 /* Note that NAME was declared (as DECL) in the current class. Check
6897 to see that the declaration is valid. */
6900 note_name_declared_in_class (tree name, tree decl)
6902 splay_tree names_used;
6905 /* Look to see if we ever used this name. */
6907 = current_class_stack[current_class_depth - 1].names_used;
6910 /* The C language allows members to be declared with a type of the same
6911 name, and the C++ standard says this diagnostic is not required. So
6912 allow it in extern "C" blocks unless predantic is specified.
6913 Allow it in all cases if -ms-extensions is specified. */
6914 if ((!pedantic && current_lang_name == lang_name_c)
6915 || flag_ms_extensions)
6917 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6920 /* [basic.scope.class]
6922 A name N used in a class S shall refer to the same declaration
6923 in its context and when re-evaluated in the completed scope of
6925 permerror (input_location, "declaration of %q#D", decl);
6926 permerror (input_location, "changes meaning of %qD from %q+#D",
6927 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6931 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6932 Secondary vtables are merged with primary vtables; this function
6933 will return the VAR_DECL for the primary vtable. */
6936 get_vtbl_decl_for_binfo (tree binfo)
6940 decl = BINFO_VTABLE (binfo);
6941 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
6943 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6944 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6947 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6952 /* Returns the binfo for the primary base of BINFO. If the resulting
6953 BINFO is a virtual base, and it is inherited elsewhere in the
6954 hierarchy, then the returned binfo might not be the primary base of
6955 BINFO in the complete object. Check BINFO_PRIMARY_P or
6956 BINFO_LOST_PRIMARY_P to be sure. */
6959 get_primary_binfo (tree binfo)
6963 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6967 return copied_binfo (primary_base, binfo);
6970 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6973 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6976 fprintf (stream, "%*s", indent, "");
6980 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6981 INDENT should be zero when called from the top level; it is
6982 incremented recursively. IGO indicates the next expected BINFO in
6983 inheritance graph ordering. */
6986 dump_class_hierarchy_r (FILE *stream,
6996 indented = maybe_indent_hierarchy (stream, indent, 0);
6997 fprintf (stream, "%s (0x%lx) ",
6998 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6999 (unsigned long) binfo);
7002 fprintf (stream, "alternative-path\n");
7005 igo = TREE_CHAIN (binfo);
7007 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
7008 tree_low_cst (BINFO_OFFSET (binfo), 0));
7009 if (is_empty_class (BINFO_TYPE (binfo)))
7010 fprintf (stream, " empty");
7011 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
7012 fprintf (stream, " nearly-empty");
7013 if (BINFO_VIRTUAL_P (binfo))
7014 fprintf (stream, " virtual");
7015 fprintf (stream, "\n");
7018 if (BINFO_PRIMARY_P (binfo))
7020 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7021 fprintf (stream, " primary-for %s (0x%lx)",
7022 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
7023 TFF_PLAIN_IDENTIFIER),
7024 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
7026 if (BINFO_LOST_PRIMARY_P (binfo))
7028 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7029 fprintf (stream, " lost-primary");
7032 fprintf (stream, "\n");
7034 if (!(flags & TDF_SLIM))
7038 if (BINFO_SUBVTT_INDEX (binfo))
7040 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7041 fprintf (stream, " subvttidx=%s",
7042 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
7043 TFF_PLAIN_IDENTIFIER));
7045 if (BINFO_VPTR_INDEX (binfo))
7047 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7048 fprintf (stream, " vptridx=%s",
7049 expr_as_string (BINFO_VPTR_INDEX (binfo),
7050 TFF_PLAIN_IDENTIFIER));
7052 if (BINFO_VPTR_FIELD (binfo))
7054 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7055 fprintf (stream, " vbaseoffset=%s",
7056 expr_as_string (BINFO_VPTR_FIELD (binfo),
7057 TFF_PLAIN_IDENTIFIER));
7059 if (BINFO_VTABLE (binfo))
7061 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7062 fprintf (stream, " vptr=%s",
7063 expr_as_string (BINFO_VTABLE (binfo),
7064 TFF_PLAIN_IDENTIFIER));
7068 fprintf (stream, "\n");
7071 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
7072 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
7077 /* Dump the BINFO hierarchy for T. */
7080 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
7082 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7083 fprintf (stream, " size=%lu align=%lu\n",
7084 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
7085 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
7086 fprintf (stream, " base size=%lu base align=%lu\n",
7087 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
7089 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
7091 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
7092 fprintf (stream, "\n");
7095 /* Debug interface to hierarchy dumping. */
7098 debug_class (tree t)
7100 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
7104 dump_class_hierarchy (tree t)
7107 FILE *stream = dump_begin (TDI_class, &flags);
7111 dump_class_hierarchy_1 (stream, flags, t);
7112 dump_end (TDI_class, stream);
7117 dump_array (FILE * stream, tree decl)
7120 unsigned HOST_WIDE_INT ix;
7122 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
7124 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
7126 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
7127 fprintf (stream, " %s entries",
7128 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
7129 TFF_PLAIN_IDENTIFIER));
7130 fprintf (stream, "\n");
7132 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
7134 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
7135 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
7139 dump_vtable (tree t, tree binfo, tree vtable)
7142 FILE *stream = dump_begin (TDI_class, &flags);
7147 if (!(flags & TDF_SLIM))
7149 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
7151 fprintf (stream, "%s for %s",
7152 ctor_vtbl_p ? "Construction vtable" : "Vtable",
7153 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
7156 if (!BINFO_VIRTUAL_P (binfo))
7157 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
7158 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7160 fprintf (stream, "\n");
7161 dump_array (stream, vtable);
7162 fprintf (stream, "\n");
7165 dump_end (TDI_class, stream);
7169 dump_vtt (tree t, tree vtt)
7172 FILE *stream = dump_begin (TDI_class, &flags);
7177 if (!(flags & TDF_SLIM))
7179 fprintf (stream, "VTT for %s\n",
7180 type_as_string (t, TFF_PLAIN_IDENTIFIER));
7181 dump_array (stream, vtt);
7182 fprintf (stream, "\n");
7185 dump_end (TDI_class, stream);
7188 /* Dump a function or thunk and its thunkees. */
7191 dump_thunk (FILE *stream, int indent, tree thunk)
7193 static const char spaces[] = " ";
7194 tree name = DECL_NAME (thunk);
7197 fprintf (stream, "%.*s%p %s %s", indent, spaces,
7199 !DECL_THUNK_P (thunk) ? "function"
7200 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
7201 name ? IDENTIFIER_POINTER (name) : "<unset>");
7202 if (DECL_THUNK_P (thunk))
7204 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
7205 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
7207 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
7208 if (!virtual_adjust)
7210 else if (DECL_THIS_THUNK_P (thunk))
7211 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
7212 tree_low_cst (virtual_adjust, 0));
7214 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
7215 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
7216 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
7217 if (THUNK_ALIAS (thunk))
7218 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
7220 fprintf (stream, "\n");
7221 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
7222 dump_thunk (stream, indent + 2, thunks);
7225 /* Dump the thunks for FN. */
7228 debug_thunks (tree fn)
7230 dump_thunk (stderr, 0, fn);
7233 /* Virtual function table initialization. */
7235 /* Create all the necessary vtables for T and its base classes. */
7238 finish_vtbls (tree t)
7241 VEC(constructor_elt,gc) *v = NULL;
7242 tree vtable = BINFO_VTABLE (TYPE_BINFO (t));
7244 /* We lay out the primary and secondary vtables in one contiguous
7245 vtable. The primary vtable is first, followed by the non-virtual
7246 secondary vtables in inheritance graph order. */
7247 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t),
7250 /* Then come the virtual bases, also in inheritance graph order. */
7251 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
7253 if (!BINFO_VIRTUAL_P (vbase))
7255 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), vtable, t, &v);
7258 if (BINFO_VTABLE (TYPE_BINFO (t)))
7259 initialize_vtable (TYPE_BINFO (t), v);
7262 /* Initialize the vtable for BINFO with the INITS. */
7265 initialize_vtable (tree binfo, VEC(constructor_elt,gc) *inits)
7269 layout_vtable_decl (binfo, VEC_length (constructor_elt, inits));
7270 decl = get_vtbl_decl_for_binfo (binfo);
7271 initialize_artificial_var (decl, inits);
7272 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
7275 /* Build the VTT (virtual table table) for T.
7276 A class requires a VTT if it has virtual bases.
7279 1 - primary virtual pointer for complete object T
7280 2 - secondary VTTs for each direct non-virtual base of T which requires a
7282 3 - secondary virtual pointers for each direct or indirect base of T which
7283 has virtual bases or is reachable via a virtual path from T.
7284 4 - secondary VTTs for each direct or indirect virtual base of T.
7286 Secondary VTTs look like complete object VTTs without part 4. */
7294 VEC(constructor_elt,gc) *inits;
7296 /* Build up the initializers for the VTT. */
7298 index = size_zero_node;
7299 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7301 /* If we didn't need a VTT, we're done. */
7305 /* Figure out the type of the VTT. */
7306 type = build_array_of_n_type (const_ptr_type_node,
7307 VEC_length (constructor_elt, inits));
7309 /* Now, build the VTT object itself. */
7310 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7311 initialize_artificial_var (vtt, inits);
7312 /* Add the VTT to the vtables list. */
7313 DECL_CHAIN (vtt) = DECL_CHAIN (CLASSTYPE_VTABLES (t));
7314 DECL_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7319 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7320 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7321 and CHAIN the vtable pointer for this binfo after construction is
7322 complete. VALUE can also be another BINFO, in which case we recurse. */
7325 binfo_ctor_vtable (tree binfo)
7331 vt = BINFO_VTABLE (binfo);
7332 if (TREE_CODE (vt) == TREE_LIST)
7333 vt = TREE_VALUE (vt);
7334 if (TREE_CODE (vt) == TREE_BINFO)
7343 /* Data for secondary VTT initialization. */
7344 typedef struct secondary_vptr_vtt_init_data_s
7346 /* Is this the primary VTT? */
7349 /* Current index into the VTT. */
7352 /* Vector of initializers built up. */
7353 VEC(constructor_elt,gc) *inits;
7355 /* The type being constructed by this secondary VTT. */
7356 tree type_being_constructed;
7357 } secondary_vptr_vtt_init_data;
7359 /* Recursively build the VTT-initializer for BINFO (which is in the
7360 hierarchy dominated by T). INITS points to the end of the initializer
7361 list to date. INDEX is the VTT index where the next element will be
7362 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7363 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7364 for virtual bases of T. When it is not so, we build the constructor
7365 vtables for the BINFO-in-T variant. */
7368 build_vtt_inits (tree binfo, tree t, VEC(constructor_elt,gc) **inits, tree *index)
7373 secondary_vptr_vtt_init_data data;
7374 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7376 /* We only need VTTs for subobjects with virtual bases. */
7377 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7380 /* We need to use a construction vtable if this is not the primary
7384 build_ctor_vtbl_group (binfo, t);
7386 /* Record the offset in the VTT where this sub-VTT can be found. */
7387 BINFO_SUBVTT_INDEX (binfo) = *index;
7390 /* Add the address of the primary vtable for the complete object. */
7391 init = binfo_ctor_vtable (binfo);
7392 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7395 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7396 BINFO_VPTR_INDEX (binfo) = *index;
7398 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7400 /* Recursively add the secondary VTTs for non-virtual bases. */
7401 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7402 if (!BINFO_VIRTUAL_P (b))
7403 build_vtt_inits (b, t, inits, index);
7405 /* Add secondary virtual pointers for all subobjects of BINFO with
7406 either virtual bases or reachable along a virtual path, except
7407 subobjects that are non-virtual primary bases. */
7408 data.top_level_p = top_level_p;
7409 data.index = *index;
7410 data.inits = *inits;
7411 data.type_being_constructed = BINFO_TYPE (binfo);
7413 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7415 *index = data.index;
7417 /* data.inits might have grown as we added secondary virtual pointers.
7418 Make sure our caller knows about the new vector. */
7419 *inits = data.inits;
7422 /* Add the secondary VTTs for virtual bases in inheritance graph
7424 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7426 if (!BINFO_VIRTUAL_P (b))
7429 build_vtt_inits (b, t, inits, index);
7432 /* Remove the ctor vtables we created. */
7433 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7436 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7437 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7440 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7442 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7444 /* We don't care about bases that don't have vtables. */
7445 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7446 return dfs_skip_bases;
7448 /* We're only interested in proper subobjects of the type being
7450 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7453 /* We're only interested in bases with virtual bases or reachable
7454 via a virtual path from the type being constructed. */
7455 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7456 || binfo_via_virtual (binfo, data->type_being_constructed)))
7457 return dfs_skip_bases;
7459 /* We're not interested in non-virtual primary bases. */
7460 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7463 /* Record the index where this secondary vptr can be found. */
7464 if (data->top_level_p)
7466 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7467 BINFO_VPTR_INDEX (binfo) = data->index;
7469 if (BINFO_VIRTUAL_P (binfo))
7471 /* It's a primary virtual base, and this is not a
7472 construction vtable. Find the base this is primary of in
7473 the inheritance graph, and use that base's vtable
7475 while (BINFO_PRIMARY_P (binfo))
7476 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7480 /* Add the initializer for the secondary vptr itself. */
7481 CONSTRUCTOR_APPEND_ELT (data->inits, NULL_TREE, binfo_ctor_vtable (binfo));
7483 /* Advance the vtt index. */
7484 data->index = size_binop (PLUS_EXPR, data->index,
7485 TYPE_SIZE_UNIT (ptr_type_node));
7490 /* Called from build_vtt_inits via dfs_walk. After building
7491 constructor vtables and generating the sub-vtt from them, we need
7492 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7493 binfo of the base whose sub vtt was generated. */
7496 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7498 tree vtable = BINFO_VTABLE (binfo);
7500 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7501 /* If this class has no vtable, none of its bases do. */
7502 return dfs_skip_bases;
7505 /* This might be a primary base, so have no vtable in this
7509 /* If we scribbled the construction vtable vptr into BINFO, clear it
7511 if (TREE_CODE (vtable) == TREE_LIST
7512 && (TREE_PURPOSE (vtable) == (tree) data))
7513 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7518 /* Build the construction vtable group for BINFO which is in the
7519 hierarchy dominated by T. */
7522 build_ctor_vtbl_group (tree binfo, tree t)
7528 VEC(constructor_elt,gc) *v;
7530 /* See if we've already created this construction vtable group. */
7531 id = mangle_ctor_vtbl_for_type (t, binfo);
7532 if (IDENTIFIER_GLOBAL_VALUE (id))
7535 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7536 /* Build a version of VTBL (with the wrong type) for use in
7537 constructing the addresses of secondary vtables in the
7538 construction vtable group. */
7539 vtbl = build_vtable (t, id, ptr_type_node);
7540 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7543 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7544 binfo, vtbl, t, &v);
7546 /* Add the vtables for each of our virtual bases using the vbase in T
7548 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7550 vbase = TREE_CHAIN (vbase))
7554 if (!BINFO_VIRTUAL_P (vbase))
7556 b = copied_binfo (vbase, binfo);
7558 accumulate_vtbl_inits (b, vbase, binfo, vtbl, t, &v);
7561 /* Figure out the type of the construction vtable. */
7562 type = build_array_of_n_type (vtable_entry_type,
7563 VEC_length (constructor_elt, v));
7565 TREE_TYPE (vtbl) = type;
7566 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7567 layout_decl (vtbl, 0);
7569 /* Initialize the construction vtable. */
7570 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7571 initialize_artificial_var (vtbl, v);
7572 dump_vtable (t, binfo, vtbl);
7575 /* Add the vtbl initializers for BINFO (and its bases other than
7576 non-virtual primaries) to the list of INITS. BINFO is in the
7577 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7578 the constructor the vtbl inits should be accumulated for. (If this
7579 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7580 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7581 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7582 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7583 but are not necessarily the same in terms of layout. */
7586 accumulate_vtbl_inits (tree binfo,
7591 VEC(constructor_elt,gc) **inits)
7595 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7597 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7599 /* If it doesn't have a vptr, we don't do anything. */
7600 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7603 /* If we're building a construction vtable, we're not interested in
7604 subobjects that don't require construction vtables. */
7606 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7607 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7610 /* Build the initializers for the BINFO-in-T vtable. */
7611 dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, vtbl, t, inits);
7613 /* Walk the BINFO and its bases. We walk in preorder so that as we
7614 initialize each vtable we can figure out at what offset the
7615 secondary vtable lies from the primary vtable. We can't use
7616 dfs_walk here because we need to iterate through bases of BINFO
7617 and RTTI_BINFO simultaneously. */
7618 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7620 /* Skip virtual bases. */
7621 if (BINFO_VIRTUAL_P (base_binfo))
7623 accumulate_vtbl_inits (base_binfo,
7624 BINFO_BASE_BINFO (orig_binfo, i),
7625 rtti_binfo, vtbl, t,
7630 /* Called from accumulate_vtbl_inits. Adds the initializers for the
7631 BINFO vtable to L. */
7634 dfs_accumulate_vtbl_inits (tree binfo,
7639 VEC(constructor_elt,gc) **l)
7641 tree vtbl = NULL_TREE;
7642 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7646 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7648 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7649 primary virtual base. If it is not the same primary in
7650 the hierarchy of T, we'll need to generate a ctor vtable
7651 for it, to place at its location in T. If it is the same
7652 primary, we still need a VTT entry for the vtable, but it
7653 should point to the ctor vtable for the base it is a
7654 primary for within the sub-hierarchy of RTTI_BINFO.
7656 There are three possible cases:
7658 1) We are in the same place.
7659 2) We are a primary base within a lost primary virtual base of
7661 3) We are primary to something not a base of RTTI_BINFO. */
7664 tree last = NULL_TREE;
7666 /* First, look through the bases we are primary to for RTTI_BINFO
7667 or a virtual base. */
7669 while (BINFO_PRIMARY_P (b))
7671 b = BINFO_INHERITANCE_CHAIN (b);
7673 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7676 /* If we run out of primary links, keep looking down our
7677 inheritance chain; we might be an indirect primary. */
7678 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7679 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7683 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7684 base B and it is a base of RTTI_BINFO, this is case 2. In
7685 either case, we share our vtable with LAST, i.e. the
7686 derived-most base within B of which we are a primary. */
7688 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7689 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7690 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7691 binfo_ctor_vtable after everything's been set up. */
7694 /* Otherwise, this is case 3 and we get our own. */
7696 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7699 n_inits = VEC_length (constructor_elt, *l);
7706 /* Add the initializer for this vtable. */
7707 build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7708 &non_fn_entries, l);
7710 /* Figure out the position to which the VPTR should point. */
7711 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, orig_vtbl);
7712 index = size_binop (PLUS_EXPR,
7713 size_int (non_fn_entries),
7714 size_int (n_inits));
7715 index = size_binop (MULT_EXPR,
7716 TYPE_SIZE_UNIT (vtable_entry_type),
7718 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7722 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7723 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7724 straighten this out. */
7725 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7726 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7727 /* Throw away any unneeded intializers. */
7728 VEC_truncate (constructor_elt, *l, n_inits);
7730 /* For an ordinary vtable, set BINFO_VTABLE. */
7731 BINFO_VTABLE (binfo) = vtbl;
7734 static GTY(()) tree abort_fndecl_addr;
7736 /* Construct the initializer for BINFO's virtual function table. BINFO
7737 is part of the hierarchy dominated by T. If we're building a
7738 construction vtable, the ORIG_BINFO is the binfo we should use to
7739 find the actual function pointers to put in the vtable - but they
7740 can be overridden on the path to most-derived in the graph that
7741 ORIG_BINFO belongs. Otherwise,
7742 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7743 BINFO that should be indicated by the RTTI information in the
7744 vtable; it will be a base class of T, rather than T itself, if we
7745 are building a construction vtable.
7747 The value returned is a TREE_LIST suitable for wrapping in a
7748 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7749 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7750 number of non-function entries in the vtable.
7752 It might seem that this function should never be called with a
7753 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7754 base is always subsumed by a derived class vtable. However, when
7755 we are building construction vtables, we do build vtables for
7756 primary bases; we need these while the primary base is being
7760 build_vtbl_initializer (tree binfo,
7764 int* non_fn_entries_p,
7765 VEC(constructor_elt,gc) **inits)
7771 VEC(tree,gc) *vbases;
7774 /* Initialize VID. */
7775 memset (&vid, 0, sizeof (vid));
7778 vid.rtti_binfo = rtti_binfo;
7779 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7780 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7781 vid.generate_vcall_entries = true;
7782 /* The first vbase or vcall offset is at index -3 in the vtable. */
7783 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7785 /* Add entries to the vtable for RTTI. */
7786 build_rtti_vtbl_entries (binfo, &vid);
7788 /* Create an array for keeping track of the functions we've
7789 processed. When we see multiple functions with the same
7790 signature, we share the vcall offsets. */
7791 vid.fns = VEC_alloc (tree, gc, 32);
7792 /* Add the vcall and vbase offset entries. */
7793 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7795 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7796 build_vbase_offset_vtbl_entries. */
7797 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7798 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7799 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7801 /* If the target requires padding between data entries, add that now. */
7802 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7804 int n_entries = VEC_length (constructor_elt, vid.inits);
7806 VEC_safe_grow (constructor_elt, gc, vid.inits,
7807 TARGET_VTABLE_DATA_ENTRY_DISTANCE * n_entries);
7809 /* Move data entries into their new positions and add padding
7810 after the new positions. Iterate backwards so we don't
7811 overwrite entries that we would need to process later. */
7812 for (ix = n_entries - 1;
7813 VEC_iterate (constructor_elt, vid.inits, ix, e);
7817 int new_position = (TARGET_VTABLE_DATA_ENTRY_DISTANCE * ix
7818 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE - 1));
7820 VEC_replace (constructor_elt, vid.inits, new_position, e);
7822 for (j = 1; j < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++j)
7824 constructor_elt *f = VEC_index (constructor_elt, vid.inits,
7826 f->index = NULL_TREE;
7827 f->value = build1 (NOP_EXPR, vtable_entry_type,
7833 if (non_fn_entries_p)
7834 *non_fn_entries_p = VEC_length (constructor_elt, vid.inits);
7836 /* The initializers for virtual functions were built up in reverse
7837 order. Straighten them out and add them to the running list in one
7839 jx = VEC_length (constructor_elt, *inits);
7840 VEC_safe_grow (constructor_elt, gc, *inits,
7841 (jx + VEC_length (constructor_elt, vid.inits)));
7843 for (ix = VEC_length (constructor_elt, vid.inits) - 1;
7844 VEC_iterate (constructor_elt, vid.inits, ix, e);
7846 VEC_replace (constructor_elt, *inits, jx, e);
7848 /* Go through all the ordinary virtual functions, building up
7850 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7854 tree fn, fn_original;
7855 tree init = NULL_TREE;
7859 if (DECL_THUNK_P (fn))
7861 if (!DECL_NAME (fn))
7863 if (THUNK_ALIAS (fn))
7865 fn = THUNK_ALIAS (fn);
7868 fn_original = THUNK_TARGET (fn);
7871 /* If the only definition of this function signature along our
7872 primary base chain is from a lost primary, this vtable slot will
7873 never be used, so just zero it out. This is important to avoid
7874 requiring extra thunks which cannot be generated with the function.
7876 We first check this in update_vtable_entry_for_fn, so we handle
7877 restored primary bases properly; we also need to do it here so we
7878 zero out unused slots in ctor vtables, rather than filling them
7879 with erroneous values (though harmless, apart from relocation
7881 if (BV_LOST_PRIMARY (v))
7882 init = size_zero_node;
7886 /* Pull the offset for `this', and the function to call, out of
7888 delta = BV_DELTA (v);
7889 vcall_index = BV_VCALL_INDEX (v);
7891 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7892 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7894 /* You can't call an abstract virtual function; it's abstract.
7895 So, we replace these functions with __pure_virtual. */
7896 if (DECL_PURE_VIRTUAL_P (fn_original))
7899 if (!TARGET_VTABLE_USES_DESCRIPTORS)
7901 if (abort_fndecl_addr == NULL)
7903 = fold_convert (vfunc_ptr_type_node,
7904 build_fold_addr_expr (fn));
7905 init = abort_fndecl_addr;
7910 if (!integer_zerop (delta) || vcall_index)
7912 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7913 if (!DECL_NAME (fn))
7916 /* Take the address of the function, considering it to be of an
7917 appropriate generic type. */
7918 if (!TARGET_VTABLE_USES_DESCRIPTORS)
7919 init = fold_convert (vfunc_ptr_type_node,
7920 build_fold_addr_expr (fn));
7924 /* And add it to the chain of initializers. */
7925 if (TARGET_VTABLE_USES_DESCRIPTORS)
7928 if (init == size_zero_node)
7929 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7930 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7932 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7934 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7935 fn, build_int_cst (NULL_TREE, i));
7936 TREE_CONSTANT (fdesc) = 1;
7938 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, fdesc);
7942 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7946 /* Adds to vid->inits the initializers for the vbase and vcall
7947 offsets in BINFO, which is in the hierarchy dominated by T. */
7950 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7954 /* If this is a derived class, we must first create entries
7955 corresponding to the primary base class. */
7956 b = get_primary_binfo (binfo);
7958 build_vcall_and_vbase_vtbl_entries (b, vid);
7960 /* Add the vbase entries for this base. */
7961 build_vbase_offset_vtbl_entries (binfo, vid);
7962 /* Add the vcall entries for this base. */
7963 build_vcall_offset_vtbl_entries (binfo, vid);
7966 /* Returns the initializers for the vbase offset entries in the vtable
7967 for BINFO (which is part of the class hierarchy dominated by T), in
7968 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7969 where the next vbase offset will go. */
7972 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7976 tree non_primary_binfo;
7978 /* If there are no virtual baseclasses, then there is nothing to
7980 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7985 /* We might be a primary base class. Go up the inheritance hierarchy
7986 until we find the most derived class of which we are a primary base:
7987 it is the offset of that which we need to use. */
7988 non_primary_binfo = binfo;
7989 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7993 /* If we have reached a virtual base, then it must be a primary
7994 base (possibly multi-level) of vid->binfo, or we wouldn't
7995 have called build_vcall_and_vbase_vtbl_entries for it. But it
7996 might be a lost primary, so just skip down to vid->binfo. */
7997 if (BINFO_VIRTUAL_P (non_primary_binfo))
7999 non_primary_binfo = vid->binfo;
8003 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8004 if (get_primary_binfo (b) != non_primary_binfo)
8006 non_primary_binfo = b;
8009 /* Go through the virtual bases, adding the offsets. */
8010 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
8012 vbase = TREE_CHAIN (vbase))
8017 if (!BINFO_VIRTUAL_P (vbase))
8020 /* Find the instance of this virtual base in the complete
8022 b = copied_binfo (vbase, binfo);
8024 /* If we've already got an offset for this virtual base, we
8025 don't need another one. */
8026 if (BINFO_VTABLE_PATH_MARKED (b))
8028 BINFO_VTABLE_PATH_MARKED (b) = 1;
8030 /* Figure out where we can find this vbase offset. */
8031 delta = size_binop (MULT_EXPR,
8034 TYPE_SIZE_UNIT (vtable_entry_type)));
8035 if (vid->primary_vtbl_p)
8036 BINFO_VPTR_FIELD (b) = delta;
8038 if (binfo != TYPE_BINFO (t))
8039 /* The vbase offset had better be the same. */
8040 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
8042 /* The next vbase will come at a more negative offset. */
8043 vid->index = size_binop (MINUS_EXPR, vid->index,
8044 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8046 /* The initializer is the delta from BINFO to this virtual base.
8047 The vbase offsets go in reverse inheritance-graph order, and
8048 we are walking in inheritance graph order so these end up in
8050 delta = size_diffop_loc (input_location,
8051 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
8053 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE,
8054 fold_build1_loc (input_location, NOP_EXPR,
8055 vtable_entry_type, delta));
8059 /* Adds the initializers for the vcall offset entries in the vtable
8060 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
8064 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8066 /* We only need these entries if this base is a virtual base. We
8067 compute the indices -- but do not add to the vtable -- when
8068 building the main vtable for a class. */
8069 if (binfo == TYPE_BINFO (vid->derived)
8070 || (BINFO_VIRTUAL_P (binfo)
8071 /* If BINFO is RTTI_BINFO, then (since BINFO does not
8072 correspond to VID->DERIVED), we are building a primary
8073 construction virtual table. Since this is a primary
8074 virtual table, we do not need the vcall offsets for
8076 && binfo != vid->rtti_binfo))
8078 /* We need a vcall offset for each of the virtual functions in this
8079 vtable. For example:
8081 class A { virtual void f (); };
8082 class B1 : virtual public A { virtual void f (); };
8083 class B2 : virtual public A { virtual void f (); };
8084 class C: public B1, public B2 { virtual void f (); };
8086 A C object has a primary base of B1, which has a primary base of A. A
8087 C also has a secondary base of B2, which no longer has a primary base
8088 of A. So the B2-in-C construction vtable needs a secondary vtable for
8089 A, which will adjust the A* to a B2* to call f. We have no way of
8090 knowing what (or even whether) this offset will be when we define B2,
8091 so we store this "vcall offset" in the A sub-vtable and look it up in
8092 a "virtual thunk" for B2::f.
8094 We need entries for all the functions in our primary vtable and
8095 in our non-virtual bases' secondary vtables. */
8097 /* If we are just computing the vcall indices -- but do not need
8098 the actual entries -- not that. */
8099 if (!BINFO_VIRTUAL_P (binfo))
8100 vid->generate_vcall_entries = false;
8101 /* Now, walk through the non-virtual bases, adding vcall offsets. */
8102 add_vcall_offset_vtbl_entries_r (binfo, vid);
8106 /* Build vcall offsets, starting with those for BINFO. */
8109 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
8115 /* Don't walk into virtual bases -- except, of course, for the
8116 virtual base for which we are building vcall offsets. Any
8117 primary virtual base will have already had its offsets generated
8118 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8119 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
8122 /* If BINFO has a primary base, process it first. */
8123 primary_binfo = get_primary_binfo (binfo);
8125 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
8127 /* Add BINFO itself to the list. */
8128 add_vcall_offset_vtbl_entries_1 (binfo, vid);
8130 /* Scan the non-primary bases of BINFO. */
8131 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8132 if (base_binfo != primary_binfo)
8133 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
8136 /* Called from build_vcall_offset_vtbl_entries_r. */
8139 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
8141 /* Make entries for the rest of the virtuals. */
8142 if (abi_version_at_least (2))
8146 /* The ABI requires that the methods be processed in declaration
8147 order. G++ 3.2 used the order in the vtable. */
8148 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
8150 orig_fn = DECL_CHAIN (orig_fn))
8151 if (DECL_VINDEX (orig_fn))
8152 add_vcall_offset (orig_fn, binfo, vid);
8156 tree derived_virtuals;
8159 /* If BINFO is a primary base, the most derived class which has
8160 BINFO as a primary base; otherwise, just BINFO. */
8161 tree non_primary_binfo;
8163 /* We might be a primary base class. Go up the inheritance hierarchy
8164 until we find the most derived class of which we are a primary base:
8165 it is the BINFO_VIRTUALS there that we need to consider. */
8166 non_primary_binfo = binfo;
8167 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8171 /* If we have reached a virtual base, then it must be vid->vbase,
8172 because we ignore other virtual bases in
8173 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8174 base (possibly multi-level) of vid->binfo, or we wouldn't
8175 have called build_vcall_and_vbase_vtbl_entries for it. But it
8176 might be a lost primary, so just skip down to vid->binfo. */
8177 if (BINFO_VIRTUAL_P (non_primary_binfo))
8179 gcc_assert (non_primary_binfo == vid->vbase);
8180 non_primary_binfo = vid->binfo;
8184 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8185 if (get_primary_binfo (b) != non_primary_binfo)
8187 non_primary_binfo = b;
8190 if (vid->ctor_vtbl_p)
8191 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8192 where rtti_binfo is the most derived type. */
8194 = original_binfo (non_primary_binfo, vid->rtti_binfo);
8196 for (base_virtuals = BINFO_VIRTUALS (binfo),
8197 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
8198 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
8200 base_virtuals = TREE_CHAIN (base_virtuals),
8201 derived_virtuals = TREE_CHAIN (derived_virtuals),
8202 orig_virtuals = TREE_CHAIN (orig_virtuals))
8206 /* Find the declaration that originally caused this function to
8207 be present in BINFO_TYPE (binfo). */
8208 orig_fn = BV_FN (orig_virtuals);
8210 /* When processing BINFO, we only want to generate vcall slots for
8211 function slots introduced in BINFO. So don't try to generate
8212 one if the function isn't even defined in BINFO. */
8213 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
8216 add_vcall_offset (orig_fn, binfo, vid);
8221 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8224 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
8230 /* If there is already an entry for a function with the same
8231 signature as FN, then we do not need a second vcall offset.
8232 Check the list of functions already present in the derived
8234 FOR_EACH_VEC_ELT (tree, vid->fns, i, derived_entry)
8236 if (same_signature_p (derived_entry, orig_fn)
8237 /* We only use one vcall offset for virtual destructors,
8238 even though there are two virtual table entries. */
8239 || (DECL_DESTRUCTOR_P (derived_entry)
8240 && DECL_DESTRUCTOR_P (orig_fn)))
8244 /* If we are building these vcall offsets as part of building
8245 the vtable for the most derived class, remember the vcall
8247 if (vid->binfo == TYPE_BINFO (vid->derived))
8249 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
8250 CLASSTYPE_VCALL_INDICES (vid->derived),
8252 elt->purpose = orig_fn;
8253 elt->value = vid->index;
8256 /* The next vcall offset will be found at a more negative
8258 vid->index = size_binop (MINUS_EXPR, vid->index,
8259 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8261 /* Keep track of this function. */
8262 VEC_safe_push (tree, gc, vid->fns, orig_fn);
8264 if (vid->generate_vcall_entries)
8269 /* Find the overriding function. */
8270 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8271 if (fn == error_mark_node)
8272 vcall_offset = build_zero_cst (vtable_entry_type);
8275 base = TREE_VALUE (fn);
8277 /* The vbase we're working on is a primary base of
8278 vid->binfo. But it might be a lost primary, so its
8279 BINFO_OFFSET might be wrong, so we just use the
8280 BINFO_OFFSET from vid->binfo. */
8281 vcall_offset = size_diffop_loc (input_location,
8282 BINFO_OFFSET (base),
8283 BINFO_OFFSET (vid->binfo));
8284 vcall_offset = fold_build1_loc (input_location,
8285 NOP_EXPR, vtable_entry_type,
8288 /* Add the initializer to the vtable. */
8289 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, vcall_offset);
8293 /* Return vtbl initializers for the RTTI entries corresponding to the
8294 BINFO's vtable. The RTTI entries should indicate the object given
8295 by VID->rtti_binfo. */
8298 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8306 t = BINFO_TYPE (vid->rtti_binfo);
8308 /* To find the complete object, we will first convert to our most
8309 primary base, and then add the offset in the vtbl to that value. */
8311 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8312 && !BINFO_LOST_PRIMARY_P (b))
8316 primary_base = get_primary_binfo (b);
8317 gcc_assert (BINFO_PRIMARY_P (primary_base)
8318 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8321 offset = size_diffop_loc (input_location,
8322 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8324 /* The second entry is the address of the typeinfo object. */
8326 decl = build_address (get_tinfo_decl (t));
8328 decl = integer_zero_node;
8330 /* Convert the declaration to a type that can be stored in the
8332 init = build_nop (vfunc_ptr_type_node, decl);
8333 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8335 /* Add the offset-to-top entry. It comes earlier in the vtable than
8336 the typeinfo entry. Convert the offset to look like a
8337 function pointer, so that we can put it in the vtable. */
8338 init = build_nop (vfunc_ptr_type_node, offset);
8339 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8342 /* Fold a OBJ_TYPE_REF expression to the address of a function.
8343 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
8346 cp_fold_obj_type_ref (tree ref, tree known_type)
8348 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
8349 HOST_WIDE_INT i = 0;
8350 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
8355 i += (TARGET_VTABLE_USES_DESCRIPTORS
8356 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
8362 #ifdef ENABLE_CHECKING
8363 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
8364 DECL_VINDEX (fndecl)));
8367 cgraph_node (fndecl)->local.vtable_method = true;
8369 return build_address (fndecl);
8372 #include "gt-cp-class.h"