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);
292 /* TARGET_TYPE has been extracted from BINFO, and, is therefore always
293 cv-unqualified. Extract the cv-qualifiers from EXPR so that the
294 expression returned matches the input. */
295 target_type = cp_build_qualified_type
296 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
297 ptr_target_type = build_pointer_type (target_type);
299 /* Do we need to look in the vtable for the real offset? */
300 virtual_access = (v_binfo && fixed_type_p <= 0);
302 /* Don't bother with the calculations inside sizeof; they'll ICE if the
303 source type is incomplete and the pointer value doesn't matter. */
304 if (cp_unevaluated_operand != 0)
306 expr = build_nop (ptr_target_type, expr);
308 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
312 /* Do we need to check for a null pointer? */
313 if (want_pointer && !nonnull)
315 /* If we know the conversion will not actually change the value
316 of EXPR, then we can avoid testing the expression for NULL.
317 We have to avoid generating a COMPONENT_REF for a base class
318 field, because other parts of the compiler know that such
319 expressions are always non-NULL. */
320 if (!virtual_access && integer_zerop (offset))
321 return build_nop (ptr_target_type, expr);
322 null_test = error_mark_node;
325 /* Protect against multiple evaluation if necessary. */
326 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
327 expr = save_expr (expr);
329 /* Now that we've saved expr, build the real null test. */
332 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
333 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
337 /* If this is a simple base reference, express it as a COMPONENT_REF. */
338 if (code == PLUS_EXPR && !virtual_access
339 /* We don't build base fields for empty bases, and they aren't very
340 interesting to the optimizers anyway. */
343 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
344 expr = build_simple_base_path (expr, binfo);
346 expr = build_address (expr);
347 target_type = TREE_TYPE (expr);
353 /* Going via virtual base V_BINFO. We need the static offset
354 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
355 V_BINFO. That offset is an entry in D_BINFO's vtable. */
358 if (fixed_type_p < 0 && in_base_initializer)
360 /* In a base member initializer, we cannot rely on the
361 vtable being set up. We have to indirect via the
365 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
366 t = build_pointer_type (t);
367 v_offset = convert (t, current_vtt_parm);
368 v_offset = cp_build_indirect_ref (v_offset, RO_NULL,
369 tf_warning_or_error);
372 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, RO_NULL,
373 tf_warning_or_error),
374 TREE_TYPE (TREE_TYPE (expr)));
376 v_offset = build2 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
377 v_offset, fold_convert (sizetype, BINFO_VPTR_FIELD (v_binfo)));
378 v_offset = build1 (NOP_EXPR,
379 build_pointer_type (ptrdiff_type_node),
381 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, tf_warning_or_error);
382 TREE_CONSTANT (v_offset) = 1;
384 offset = convert_to_integer (ptrdiff_type_node,
385 size_diffop_loc (input_location, offset,
386 BINFO_OFFSET (v_binfo)));
388 if (!integer_zerop (offset))
389 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
391 if (fixed_type_p < 0)
392 /* Negative fixed_type_p means this is a constructor or destructor;
393 virtual base layout is fixed in in-charge [cd]tors, but not in
395 offset = build3 (COND_EXPR, ptrdiff_type_node,
396 build2 (EQ_EXPR, boolean_type_node,
397 current_in_charge_parm, integer_zero_node),
399 convert_to_integer (ptrdiff_type_node,
400 BINFO_OFFSET (binfo)));
406 target_type = ptr_target_type;
408 expr = build1 (NOP_EXPR, ptr_target_type, expr);
410 if (!integer_zerop (offset))
412 offset = fold_convert (sizetype, offset);
413 if (code == MINUS_EXPR)
414 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
415 expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
421 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
425 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
426 build_zero_cst (target_type));
431 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
432 Perform a derived-to-base conversion by recursively building up a
433 sequence of COMPONENT_REFs to the appropriate base fields. */
436 build_simple_base_path (tree expr, tree binfo)
438 tree type = BINFO_TYPE (binfo);
439 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
442 if (d_binfo == NULL_TREE)
446 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
448 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
449 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
450 an lvalue in the front end; only _DECLs and _REFs are lvalues
452 temp = unary_complex_lvalue (ADDR_EXPR, expr);
454 expr = cp_build_indirect_ref (temp, RO_NULL, tf_warning_or_error);
460 expr = build_simple_base_path (expr, d_binfo);
462 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
463 field; field = DECL_CHAIN (field))
464 /* Is this the base field created by build_base_field? */
465 if (TREE_CODE (field) == FIELD_DECL
466 && DECL_FIELD_IS_BASE (field)
467 && TREE_TYPE (field) == type)
469 /* We don't use build_class_member_access_expr here, as that
470 has unnecessary checks, and more importantly results in
471 recursive calls to dfs_walk_once. */
472 int type_quals = cp_type_quals (TREE_TYPE (expr));
474 expr = build3 (COMPONENT_REF,
475 cp_build_qualified_type (type, type_quals),
476 expr, field, NULL_TREE);
477 expr = fold_if_not_in_template (expr);
479 /* Mark the expression const or volatile, as appropriate.
480 Even though we've dealt with the type above, we still have
481 to mark the expression itself. */
482 if (type_quals & TYPE_QUAL_CONST)
483 TREE_READONLY (expr) = 1;
484 if (type_quals & TYPE_QUAL_VOLATILE)
485 TREE_THIS_VOLATILE (expr) = 1;
490 /* Didn't find the base field?!? */
494 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
495 type is a class type or a pointer to a class type. In the former
496 case, TYPE is also a class type; in the latter it is another
497 pointer type. If CHECK_ACCESS is true, an error message is emitted
498 if TYPE is inaccessible. If OBJECT has pointer type, the value is
499 assumed to be non-NULL. */
502 convert_to_base (tree object, tree type, bool check_access, bool nonnull,
503 tsubst_flags_t complain)
509 if (TYPE_PTR_P (TREE_TYPE (object)))
511 object_type = TREE_TYPE (TREE_TYPE (object));
512 type = TREE_TYPE (type);
515 object_type = TREE_TYPE (object);
517 access = check_access ? ba_check : ba_unique;
518 if (!(complain & tf_error))
520 binfo = lookup_base (object_type, type,
523 if (!binfo || binfo == error_mark_node)
524 return error_mark_node;
526 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
529 /* EXPR is an expression with unqualified class type. BASE is a base
530 binfo of that class type. Returns EXPR, converted to the BASE
531 type. This function assumes that EXPR is the most derived class;
532 therefore virtual bases can be found at their static offsets. */
535 convert_to_base_statically (tree expr, tree base)
539 expr_type = TREE_TYPE (expr);
540 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
544 pointer_type = build_pointer_type (expr_type);
546 /* We use fold_build2 and fold_convert below to simplify the trees
547 provided to the optimizers. It is not safe to call these functions
548 when processing a template because they do not handle C++-specific
550 gcc_assert (!processing_template_decl);
551 expr = cp_build_addr_expr (expr, tf_warning_or_error);
552 if (!integer_zerop (BINFO_OFFSET (base)))
553 expr = fold_build2_loc (input_location,
554 POINTER_PLUS_EXPR, pointer_type, expr,
555 fold_convert (sizetype, BINFO_OFFSET (base)));
556 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
557 expr = build_fold_indirect_ref_loc (input_location, expr);
565 build_vfield_ref (tree datum, tree type)
567 tree vfield, vcontext;
569 if (datum == error_mark_node)
570 return error_mark_node;
572 /* First, convert to the requested type. */
573 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
574 datum = convert_to_base (datum, type, /*check_access=*/false,
575 /*nonnull=*/true, tf_warning_or_error);
577 /* Second, the requested type may not be the owner of its own vptr.
578 If not, convert to the base class that owns it. We cannot use
579 convert_to_base here, because VCONTEXT may appear more than once
580 in the inheritance hierarchy of TYPE, and thus direct conversion
581 between the types may be ambiguous. Following the path back up
582 one step at a time via primary bases avoids the problem. */
583 vfield = TYPE_VFIELD (type);
584 vcontext = DECL_CONTEXT (vfield);
585 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
587 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
588 type = TREE_TYPE (datum);
591 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
594 /* Given an object INSTANCE, return an expression which yields the
595 vtable element corresponding to INDEX. There are many special
596 cases for INSTANCE which we take care of here, mainly to avoid
597 creating extra tree nodes when we don't have to. */
600 build_vtbl_ref_1 (tree instance, tree idx)
603 tree vtbl = NULL_TREE;
605 /* Try to figure out what a reference refers to, and
606 access its virtual function table directly. */
609 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
611 tree basetype = non_reference (TREE_TYPE (instance));
613 if (fixed_type && !cdtorp)
615 tree binfo = lookup_base (fixed_type, basetype,
616 ba_unique | ba_quiet, NULL);
618 vtbl = unshare_expr (BINFO_VTABLE (binfo));
622 vtbl = build_vfield_ref (instance, basetype);
624 aref = build_array_ref (input_location, vtbl, idx);
625 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
631 build_vtbl_ref (tree instance, tree idx)
633 tree aref = build_vtbl_ref_1 (instance, idx);
638 /* Given a stable object pointer INSTANCE_PTR, return an expression which
639 yields a function pointer corresponding to vtable element INDEX. */
642 build_vfn_ref (tree instance_ptr, tree idx)
646 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, RO_NULL,
647 tf_warning_or_error),
650 /* When using function descriptors, the address of the
651 vtable entry is treated as a function pointer. */
652 if (TARGET_VTABLE_USES_DESCRIPTORS)
653 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
654 cp_build_addr_expr (aref, tf_warning_or_error));
656 /* Remember this as a method reference, for later devirtualization. */
657 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
662 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
663 for the given TYPE. */
666 get_vtable_name (tree type)
668 return mangle_vtbl_for_type (type);
671 /* DECL is an entity associated with TYPE, like a virtual table or an
672 implicitly generated constructor. Determine whether or not DECL
673 should have external or internal linkage at the object file
674 level. This routine does not deal with COMDAT linkage and other
675 similar complexities; it simply sets TREE_PUBLIC if it possible for
676 entities in other translation units to contain copies of DECL, in
680 set_linkage_according_to_type (tree type, tree decl)
682 /* If TYPE involves a local class in a function with internal
683 linkage, then DECL should have internal linkage too. Other local
684 classes have no linkage -- but if their containing functions
685 have external linkage, it makes sense for DECL to have external
686 linkage too. That will allow template definitions to be merged,
688 if (no_linkage_check (type, /*relaxed_p=*/true))
690 TREE_PUBLIC (decl) = 0;
691 DECL_INTERFACE_KNOWN (decl) = 1;
694 TREE_PUBLIC (decl) = 1;
697 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
698 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
699 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
702 build_vtable (tree class_type, tree name, tree vtable_type)
706 decl = build_lang_decl (VAR_DECL, name, vtable_type);
707 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
708 now to avoid confusion in mangle_decl. */
709 SET_DECL_ASSEMBLER_NAME (decl, name);
710 DECL_CONTEXT (decl) = class_type;
711 DECL_ARTIFICIAL (decl) = 1;
712 TREE_STATIC (decl) = 1;
713 TREE_READONLY (decl) = 1;
714 DECL_VIRTUAL_P (decl) = 1;
715 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
716 DECL_VTABLE_OR_VTT_P (decl) = 1;
717 /* At one time the vtable info was grabbed 2 words at a time. This
718 fails on sparc unless you have 8-byte alignment. (tiemann) */
719 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
721 set_linkage_according_to_type (class_type, decl);
722 /* The vtable has not been defined -- yet. */
723 DECL_EXTERNAL (decl) = 1;
724 DECL_NOT_REALLY_EXTERN (decl) = 1;
726 /* Mark the VAR_DECL node representing the vtable itself as a
727 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
728 is rather important that such things be ignored because any
729 effort to actually generate DWARF for them will run into
730 trouble when/if we encounter code like:
733 struct S { virtual void member (); };
735 because the artificial declaration of the vtable itself (as
736 manufactured by the g++ front end) will say that the vtable is
737 a static member of `S' but only *after* the debug output for
738 the definition of `S' has already been output. This causes
739 grief because the DWARF entry for the definition of the vtable
740 will try to refer back to an earlier *declaration* of the
741 vtable as a static member of `S' and there won't be one. We
742 might be able to arrange to have the "vtable static member"
743 attached to the member list for `S' before the debug info for
744 `S' get written (which would solve the problem) but that would
745 require more intrusive changes to the g++ front end. */
746 DECL_IGNORED_P (decl) = 1;
751 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
752 or even complete. If this does not exist, create it. If COMPLETE is
753 nonzero, then complete the definition of it -- that will render it
754 impossible to actually build the vtable, but is useful to get at those
755 which are known to exist in the runtime. */
758 get_vtable_decl (tree type, int complete)
762 if (CLASSTYPE_VTABLES (type))
763 return CLASSTYPE_VTABLES (type);
765 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
766 CLASSTYPE_VTABLES (type) = decl;
770 DECL_EXTERNAL (decl) = 1;
771 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
777 /* Build the primary virtual function table for TYPE. If BINFO is
778 non-NULL, build the vtable starting with the initial approximation
779 that it is the same as the one which is the head of the association
780 list. Returns a nonzero value if a new vtable is actually
784 build_primary_vtable (tree binfo, tree type)
789 decl = get_vtable_decl (type, /*complete=*/0);
793 if (BINFO_NEW_VTABLE_MARKED (binfo))
794 /* We have already created a vtable for this base, so there's
795 no need to do it again. */
798 virtuals = copy_list (BINFO_VIRTUALS (binfo));
799 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
800 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
801 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
805 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
806 virtuals = NULL_TREE;
809 #ifdef GATHER_STATISTICS
811 n_vtable_elems += list_length (virtuals);
814 /* Initialize the association list for this type, based
815 on our first approximation. */
816 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
817 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
818 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
822 /* Give BINFO a new virtual function table which is initialized
823 with a skeleton-copy of its original initialization. The only
824 entry that changes is the `delta' entry, so we can really
825 share a lot of structure.
827 FOR_TYPE is the most derived type which caused this table to
830 Returns nonzero if we haven't met BINFO before.
832 The order in which vtables are built (by calling this function) for
833 an object must remain the same, otherwise a binary incompatibility
837 build_secondary_vtable (tree binfo)
839 if (BINFO_NEW_VTABLE_MARKED (binfo))
840 /* We already created a vtable for this base. There's no need to
844 /* Remember that we've created a vtable for this BINFO, so that we
845 don't try to do so again. */
846 SET_BINFO_NEW_VTABLE_MARKED (binfo);
848 /* Make fresh virtual list, so we can smash it later. */
849 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
851 /* Secondary vtables are laid out as part of the same structure as
852 the primary vtable. */
853 BINFO_VTABLE (binfo) = NULL_TREE;
857 /* Create a new vtable for BINFO which is the hierarchy dominated by
858 T. Return nonzero if we actually created a new vtable. */
861 make_new_vtable (tree t, tree binfo)
863 if (binfo == TYPE_BINFO (t))
864 /* In this case, it is *type*'s vtable we are modifying. We start
865 with the approximation that its vtable is that of the
866 immediate base class. */
867 return build_primary_vtable (binfo, t);
869 /* This is our very own copy of `basetype' to play with. Later,
870 we will fill in all the virtual functions that override the
871 virtual functions in these base classes which are not defined
872 by the current type. */
873 return build_secondary_vtable (binfo);
876 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
877 (which is in the hierarchy dominated by T) list FNDECL as its
878 BV_FN. DELTA is the required constant adjustment from the `this'
879 pointer where the vtable entry appears to the `this' required when
880 the function is actually called. */
883 modify_vtable_entry (tree t,
893 if (fndecl != BV_FN (v)
894 || !tree_int_cst_equal (delta, BV_DELTA (v)))
896 /* We need a new vtable for BINFO. */
897 if (make_new_vtable (t, binfo))
899 /* If we really did make a new vtable, we also made a copy
900 of the BINFO_VIRTUALS list. Now, we have to find the
901 corresponding entry in that list. */
902 *virtuals = BINFO_VIRTUALS (binfo);
903 while (BV_FN (*virtuals) != BV_FN (v))
904 *virtuals = TREE_CHAIN (*virtuals);
908 BV_DELTA (v) = delta;
909 BV_VCALL_INDEX (v) = NULL_TREE;
915 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
916 the USING_DECL naming METHOD. Returns true if the method could be
917 added to the method vec. */
920 add_method (tree type, tree method, tree using_decl)
924 bool template_conv_p = false;
926 VEC(tree,gc) *method_vec;
928 bool insert_p = false;
932 if (method == error_mark_node)
935 complete_p = COMPLETE_TYPE_P (type);
936 conv_p = DECL_CONV_FN_P (method);
938 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
939 && DECL_TEMPLATE_CONV_FN_P (method));
941 method_vec = CLASSTYPE_METHOD_VEC (type);
944 /* Make a new method vector. We start with 8 entries. We must
945 allocate at least two (for constructors and destructors), and
946 we're going to end up with an assignment operator at some
948 method_vec = VEC_alloc (tree, gc, 8);
949 /* Create slots for constructors and destructors. */
950 VEC_quick_push (tree, method_vec, NULL_TREE);
951 VEC_quick_push (tree, method_vec, NULL_TREE);
952 CLASSTYPE_METHOD_VEC (type) = method_vec;
955 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
956 grok_special_member_properties (method);
958 /* Constructors and destructors go in special slots. */
959 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
960 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
961 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
963 slot = CLASSTYPE_DESTRUCTOR_SLOT;
965 if (TYPE_FOR_JAVA (type))
967 if (!DECL_ARTIFICIAL (method))
968 error ("Java class %qT cannot have a destructor", type);
969 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
970 error ("Java class %qT cannot have an implicit non-trivial "
980 /* See if we already have an entry with this name. */
981 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
982 VEC_iterate (tree, method_vec, slot, m);
988 if (TREE_CODE (m) == TEMPLATE_DECL
989 && DECL_TEMPLATE_CONV_FN_P (m))
993 if (conv_p && !DECL_CONV_FN_P (m))
995 if (DECL_NAME (m) == DECL_NAME (method))
1001 && !DECL_CONV_FN_P (m)
1002 && DECL_NAME (m) > DECL_NAME (method))
1006 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1008 /* Check to see if we've already got this method. */
1009 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1011 tree fn = OVL_CURRENT (fns);
1017 if (TREE_CODE (fn) != TREE_CODE (method))
1020 /* [over.load] Member function declarations with the
1021 same name and the same parameter types cannot be
1022 overloaded if any of them is a static member
1023 function declaration.
1025 [namespace.udecl] When a using-declaration brings names
1026 from a base class into a derived class scope, member
1027 functions in the derived class override and/or hide member
1028 functions with the same name and parameter types in a base
1029 class (rather than conflicting). */
1030 fn_type = TREE_TYPE (fn);
1031 method_type = TREE_TYPE (method);
1032 parms1 = TYPE_ARG_TYPES (fn_type);
1033 parms2 = TYPE_ARG_TYPES (method_type);
1035 /* Compare the quals on the 'this' parm. Don't compare
1036 the whole types, as used functions are treated as
1037 coming from the using class in overload resolution. */
1038 if (! DECL_STATIC_FUNCTION_P (fn)
1039 && ! DECL_STATIC_FUNCTION_P (method)
1040 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1041 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1042 && (cp_type_quals (TREE_TYPE (TREE_VALUE (parms1)))
1043 != cp_type_quals (TREE_TYPE (TREE_VALUE (parms2)))))
1046 /* For templates, the return type and template parameters
1047 must be identical. */
1048 if (TREE_CODE (fn) == TEMPLATE_DECL
1049 && (!same_type_p (TREE_TYPE (fn_type),
1050 TREE_TYPE (method_type))
1051 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1052 DECL_TEMPLATE_PARMS (method))))
1055 if (! DECL_STATIC_FUNCTION_P (fn))
1056 parms1 = TREE_CHAIN (parms1);
1057 if (! DECL_STATIC_FUNCTION_P (method))
1058 parms2 = TREE_CHAIN (parms2);
1060 if (compparms (parms1, parms2)
1061 && (!DECL_CONV_FN_P (fn)
1062 || same_type_p (TREE_TYPE (fn_type),
1063 TREE_TYPE (method_type))))
1067 if (DECL_CONTEXT (fn) == type)
1068 /* Defer to the local function. */
1070 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1071 error ("repeated using declaration %q+D", using_decl);
1073 error ("using declaration %q+D conflicts with a previous using declaration",
1078 error ("%q+#D cannot be overloaded", method);
1079 error ("with %q+#D", fn);
1082 /* We don't call duplicate_decls here to merge the
1083 declarations because that will confuse things if the
1084 methods have inline definitions. In particular, we
1085 will crash while processing the definitions. */
1090 /* A class should never have more than one destructor. */
1091 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1094 /* Add the new binding. */
1095 overload = build_overload (method, current_fns);
1098 TYPE_HAS_CONVERSION (type) = 1;
1099 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1100 push_class_level_binding (DECL_NAME (method), overload);
1106 /* We only expect to add few methods in the COMPLETE_P case, so
1107 just make room for one more method in that case. */
1109 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1111 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1113 CLASSTYPE_METHOD_VEC (type) = method_vec;
1114 if (slot == VEC_length (tree, method_vec))
1115 VEC_quick_push (tree, method_vec, overload);
1117 VEC_quick_insert (tree, method_vec, slot, overload);
1120 /* Replace the current slot. */
1121 VEC_replace (tree, method_vec, slot, overload);
1125 /* Subroutines of finish_struct. */
1127 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1128 legit, otherwise return 0. */
1131 alter_access (tree t, tree fdecl, tree access)
1135 if (!DECL_LANG_SPECIFIC (fdecl))
1136 retrofit_lang_decl (fdecl);
1138 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1140 elem = purpose_member (t, DECL_ACCESS (fdecl));
1143 if (TREE_VALUE (elem) != access)
1145 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1146 error ("conflicting access specifications for method"
1147 " %q+D, ignored", TREE_TYPE (fdecl));
1149 error ("conflicting access specifications for field %qE, ignored",
1154 /* They're changing the access to the same thing they changed
1155 it to before. That's OK. */
1161 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1162 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1168 /* Process the USING_DECL, which is a member of T. */
1171 handle_using_decl (tree using_decl, tree t)
1173 tree decl = USING_DECL_DECLS (using_decl);
1174 tree name = DECL_NAME (using_decl);
1176 = TREE_PRIVATE (using_decl) ? access_private_node
1177 : TREE_PROTECTED (using_decl) ? access_protected_node
1178 : access_public_node;
1179 tree flist = NULL_TREE;
1182 gcc_assert (!processing_template_decl && decl);
1184 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1187 if (is_overloaded_fn (old_value))
1188 old_value = OVL_CURRENT (old_value);
1190 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1193 old_value = NULL_TREE;
1196 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1198 if (is_overloaded_fn (decl))
1203 else if (is_overloaded_fn (old_value))
1206 /* It's OK to use functions from a base when there are functions with
1207 the same name already present in the current class. */;
1210 error ("%q+D invalid in %q#T", using_decl, t);
1211 error (" because of local method %q+#D with same name",
1212 OVL_CURRENT (old_value));
1216 else if (!DECL_ARTIFICIAL (old_value))
1218 error ("%q+D invalid in %q#T", using_decl, t);
1219 error (" because of local member %q+#D with same name", old_value);
1223 /* Make type T see field decl FDECL with access ACCESS. */
1225 for (; flist; flist = OVL_NEXT (flist))
1227 add_method (t, OVL_CURRENT (flist), using_decl);
1228 alter_access (t, OVL_CURRENT (flist), access);
1231 alter_access (t, decl, access);
1234 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1235 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1236 properties of the bases. */
1239 check_bases (tree t,
1240 int* cant_have_const_ctor_p,
1241 int* no_const_asn_ref_p)
1244 int seen_non_virtual_nearly_empty_base_p;
1247 tree field = NULL_TREE;
1249 seen_non_virtual_nearly_empty_base_p = 0;
1251 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1252 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
1253 if (TREE_CODE (field) == FIELD_DECL)
1256 for (binfo = TYPE_BINFO (t), i = 0;
1257 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1259 tree basetype = TREE_TYPE (base_binfo);
1261 gcc_assert (COMPLETE_TYPE_P (basetype));
1263 if (CLASSTYPE_FINAL (basetype))
1264 error ("cannot derive from %<final%> base %qT in derived type %qT",
1267 /* If any base class is non-literal, so is the derived class. */
1268 if (!CLASSTYPE_LITERAL_P (basetype))
1269 CLASSTYPE_LITERAL_P (t) = false;
1271 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1272 here because the case of virtual functions but non-virtual
1273 dtor is handled in finish_struct_1. */
1274 if (!TYPE_POLYMORPHIC_P (basetype))
1275 warning (OPT_Weffc__,
1276 "base class %q#T has a non-virtual destructor", basetype);
1278 /* If the base class doesn't have copy constructors or
1279 assignment operators that take const references, then the
1280 derived class cannot have such a member automatically
1282 if (TYPE_HAS_COPY_CTOR (basetype)
1283 && ! TYPE_HAS_CONST_COPY_CTOR (basetype))
1284 *cant_have_const_ctor_p = 1;
1285 if (TYPE_HAS_COPY_ASSIGN (basetype)
1286 && !TYPE_HAS_CONST_COPY_ASSIGN (basetype))
1287 *no_const_asn_ref_p = 1;
1289 if (BINFO_VIRTUAL_P (base_binfo))
1290 /* A virtual base does not effect nearly emptiness. */
1292 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1294 if (seen_non_virtual_nearly_empty_base_p)
1295 /* And if there is more than one nearly empty base, then the
1296 derived class is not nearly empty either. */
1297 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1299 /* Remember we've seen one. */
1300 seen_non_virtual_nearly_empty_base_p = 1;
1302 else if (!is_empty_class (basetype))
1303 /* If the base class is not empty or nearly empty, then this
1304 class cannot be nearly empty. */
1305 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1307 /* A lot of properties from the bases also apply to the derived
1309 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1310 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1311 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1312 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
1313 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (basetype)
1314 || !TYPE_HAS_COPY_ASSIGN (basetype));
1315 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (basetype)
1316 || !TYPE_HAS_COPY_CTOR (basetype));
1317 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t)
1318 |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (basetype);
1319 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (basetype);
1320 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1321 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1322 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1323 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
1324 || TYPE_HAS_COMPLEX_DFLT (basetype));
1326 /* A standard-layout class is a class that:
1328 * has no non-standard-layout base classes, */
1329 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1330 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1333 /* ...has no base classes of the same type as the first non-static
1335 if (field && DECL_CONTEXT (field) == t
1336 && (same_type_ignoring_top_level_qualifiers_p
1337 (TREE_TYPE (field), basetype)))
1338 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1340 /* ...either has no non-static data members in the most-derived
1341 class and at most one base class with non-static data
1342 members, or has no base classes with non-static data
1344 for (basefield = TYPE_FIELDS (basetype); basefield;
1345 basefield = DECL_CHAIN (basefield))
1346 if (TREE_CODE (basefield) == FIELD_DECL)
1349 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1358 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1359 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1360 that have had a nearly-empty virtual primary base stolen by some
1361 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1365 determine_primary_bases (tree t)
1368 tree primary = NULL_TREE;
1369 tree type_binfo = TYPE_BINFO (t);
1372 /* Determine the primary bases of our bases. */
1373 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1374 base_binfo = TREE_CHAIN (base_binfo))
1376 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1378 /* See if we're the non-virtual primary of our inheritance
1380 if (!BINFO_VIRTUAL_P (base_binfo))
1382 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1383 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1386 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1387 BINFO_TYPE (parent_primary)))
1388 /* We are the primary binfo. */
1389 BINFO_PRIMARY_P (base_binfo) = 1;
1391 /* Determine if we have a virtual primary base, and mark it so.
1393 if (primary && BINFO_VIRTUAL_P (primary))
1395 tree this_primary = copied_binfo (primary, base_binfo);
1397 if (BINFO_PRIMARY_P (this_primary))
1398 /* Someone already claimed this base. */
1399 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1404 BINFO_PRIMARY_P (this_primary) = 1;
1405 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1407 /* A virtual binfo might have been copied from within
1408 another hierarchy. As we're about to use it as a
1409 primary base, make sure the offsets match. */
1410 delta = size_diffop_loc (input_location,
1412 BINFO_OFFSET (base_binfo)),
1414 BINFO_OFFSET (this_primary)));
1416 propagate_binfo_offsets (this_primary, delta);
1421 /* First look for a dynamic direct non-virtual base. */
1422 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1424 tree basetype = BINFO_TYPE (base_binfo);
1426 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1428 primary = base_binfo;
1433 /* A "nearly-empty" virtual base class can be the primary base
1434 class, if no non-virtual polymorphic base can be found. Look for
1435 a nearly-empty virtual dynamic base that is not already a primary
1436 base of something in the hierarchy. If there is no such base,
1437 just pick the first nearly-empty virtual base. */
1439 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1440 base_binfo = TREE_CHAIN (base_binfo))
1441 if (BINFO_VIRTUAL_P (base_binfo)
1442 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1444 if (!BINFO_PRIMARY_P (base_binfo))
1446 /* Found one that is not primary. */
1447 primary = base_binfo;
1451 /* Remember the first candidate. */
1452 primary = base_binfo;
1456 /* If we've got a primary base, use it. */
1459 tree basetype = BINFO_TYPE (primary);
1461 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1462 if (BINFO_PRIMARY_P (primary))
1463 /* We are stealing a primary base. */
1464 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1465 BINFO_PRIMARY_P (primary) = 1;
1466 if (BINFO_VIRTUAL_P (primary))
1470 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1471 /* A virtual binfo might have been copied from within
1472 another hierarchy. As we're about to use it as a primary
1473 base, make sure the offsets match. */
1474 delta = size_diffop_loc (input_location, ssize_int (0),
1475 convert (ssizetype, BINFO_OFFSET (primary)));
1477 propagate_binfo_offsets (primary, delta);
1480 primary = TYPE_BINFO (basetype);
1482 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1483 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1484 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1488 /* Update the variant types of T. */
1491 fixup_type_variants (tree t)
1498 for (variants = TYPE_NEXT_VARIANT (t);
1500 variants = TYPE_NEXT_VARIANT (variants))
1502 /* These fields are in the _TYPE part of the node, not in
1503 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1504 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1505 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1506 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1507 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1509 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1511 TYPE_BINFO (variants) = TYPE_BINFO (t);
1513 /* Copy whatever these are holding today. */
1514 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1515 TYPE_METHODS (variants) = TYPE_METHODS (t);
1516 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1520 /* Early variant fixups: we apply attributes at the beginning of the class
1521 definition, and we need to fix up any variants that have already been
1522 made via elaborated-type-specifier so that check_qualified_type works. */
1525 fixup_attribute_variants (tree t)
1532 for (variants = TYPE_NEXT_VARIANT (t);
1534 variants = TYPE_NEXT_VARIANT (variants))
1536 /* These are the two fields that check_qualified_type looks at and
1537 are affected by attributes. */
1538 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1539 TYPE_ALIGN (variants) = TYPE_ALIGN (t);
1543 /* Set memoizing fields and bits of T (and its variants) for later
1547 finish_struct_bits (tree t)
1549 /* Fix up variants (if any). */
1550 fixup_type_variants (t);
1552 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1553 /* For a class w/o baseclasses, 'finish_struct' has set
1554 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1555 Similarly for a class whose base classes do not have vtables.
1556 When neither of these is true, we might have removed abstract
1557 virtuals (by providing a definition), added some (by declaring
1558 new ones), or redeclared ones from a base class. We need to
1559 recalculate what's really an abstract virtual at this point (by
1560 looking in the vtables). */
1561 get_pure_virtuals (t);
1563 /* If this type has a copy constructor or a destructor, force its
1564 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1565 nonzero. This will cause it to be passed by invisible reference
1566 and prevent it from being returned in a register. */
1567 if (type_has_nontrivial_copy_init (t)
1568 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1571 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1572 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1574 SET_TYPE_MODE (variants, BLKmode);
1575 TREE_ADDRESSABLE (variants) = 1;
1580 /* Issue warnings about T having private constructors, but no friends,
1583 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1584 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1585 non-private static member functions. */
1588 maybe_warn_about_overly_private_class (tree t)
1590 int has_member_fn = 0;
1591 int has_nonprivate_method = 0;
1594 if (!warn_ctor_dtor_privacy
1595 /* If the class has friends, those entities might create and
1596 access instances, so we should not warn. */
1597 || (CLASSTYPE_FRIEND_CLASSES (t)
1598 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1599 /* We will have warned when the template was declared; there's
1600 no need to warn on every instantiation. */
1601 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1602 /* There's no reason to even consider warning about this
1606 /* We only issue one warning, if more than one applies, because
1607 otherwise, on code like:
1610 // Oops - forgot `public:'
1616 we warn several times about essentially the same problem. */
1618 /* Check to see if all (non-constructor, non-destructor) member
1619 functions are private. (Since there are no friends or
1620 non-private statics, we can't ever call any of the private member
1622 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
1623 /* We're not interested in compiler-generated methods; they don't
1624 provide any way to call private members. */
1625 if (!DECL_ARTIFICIAL (fn))
1627 if (!TREE_PRIVATE (fn))
1629 if (DECL_STATIC_FUNCTION_P (fn))
1630 /* A non-private static member function is just like a
1631 friend; it can create and invoke private member
1632 functions, and be accessed without a class
1636 has_nonprivate_method = 1;
1637 /* Keep searching for a static member function. */
1639 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1643 if (!has_nonprivate_method && has_member_fn)
1645 /* There are no non-private methods, and there's at least one
1646 private member function that isn't a constructor or
1647 destructor. (If all the private members are
1648 constructors/destructors we want to use the code below that
1649 issues error messages specifically referring to
1650 constructors/destructors.) */
1652 tree binfo = TYPE_BINFO (t);
1654 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1655 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1657 has_nonprivate_method = 1;
1660 if (!has_nonprivate_method)
1662 warning (OPT_Wctor_dtor_privacy,
1663 "all member functions in class %qT are private", t);
1668 /* Even if some of the member functions are non-private, the class
1669 won't be useful for much if all the constructors or destructors
1670 are private: such an object can never be created or destroyed. */
1671 fn = CLASSTYPE_DESTRUCTORS (t);
1672 if (fn && TREE_PRIVATE (fn))
1674 warning (OPT_Wctor_dtor_privacy,
1675 "%q#T only defines a private destructor and has no friends",
1680 /* Warn about classes that have private constructors and no friends. */
1681 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1682 /* Implicitly generated constructors are always public. */
1683 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1684 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1686 int nonprivate_ctor = 0;
1688 /* If a non-template class does not define a copy
1689 constructor, one is defined for it, enabling it to avoid
1690 this warning. For a template class, this does not
1691 happen, and so we would normally get a warning on:
1693 template <class T> class C { private: C(); };
1695 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1696 complete non-template or fully instantiated classes have this
1698 if (!TYPE_HAS_COPY_CTOR (t))
1699 nonprivate_ctor = 1;
1701 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1703 tree ctor = OVL_CURRENT (fn);
1704 /* Ideally, we wouldn't count copy constructors (or, in
1705 fact, any constructor that takes an argument of the
1706 class type as a parameter) because such things cannot
1707 be used to construct an instance of the class unless
1708 you already have one. But, for now at least, we're
1710 if (! TREE_PRIVATE (ctor))
1712 nonprivate_ctor = 1;
1717 if (nonprivate_ctor == 0)
1719 warning (OPT_Wctor_dtor_privacy,
1720 "%q#T only defines private constructors and has no friends",
1728 gt_pointer_operator new_value;
1732 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1735 method_name_cmp (const void* m1_p, const void* m2_p)
1737 const tree *const m1 = (const tree *) m1_p;
1738 const tree *const m2 = (const tree *) m2_p;
1740 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1742 if (*m1 == NULL_TREE)
1744 if (*m2 == NULL_TREE)
1746 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1751 /* This routine compares two fields like method_name_cmp but using the
1752 pointer operator in resort_field_decl_data. */
1755 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1757 const tree *const m1 = (const tree *) m1_p;
1758 const tree *const m2 = (const tree *) m2_p;
1759 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1761 if (*m1 == NULL_TREE)
1763 if (*m2 == NULL_TREE)
1766 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1767 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1768 resort_data.new_value (&d1, resort_data.cookie);
1769 resort_data.new_value (&d2, resort_data.cookie);
1776 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1779 resort_type_method_vec (void* obj,
1780 void* orig_obj ATTRIBUTE_UNUSED ,
1781 gt_pointer_operator new_value,
1784 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1785 int len = VEC_length (tree, method_vec);
1789 /* The type conversion ops have to live at the front of the vec, so we
1791 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1792 VEC_iterate (tree, method_vec, slot, fn);
1794 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1799 resort_data.new_value = new_value;
1800 resort_data.cookie = cookie;
1801 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1802 resort_method_name_cmp);
1806 /* Warn about duplicate methods in fn_fields.
1808 Sort methods that are not special (i.e., constructors, destructors,
1809 and type conversion operators) so that we can find them faster in
1813 finish_struct_methods (tree t)
1816 VEC(tree,gc) *method_vec;
1819 method_vec = CLASSTYPE_METHOD_VEC (t);
1823 len = VEC_length (tree, method_vec);
1825 /* Clear DECL_IN_AGGR_P for all functions. */
1826 for (fn_fields = TYPE_METHODS (t); fn_fields;
1827 fn_fields = DECL_CHAIN (fn_fields))
1828 DECL_IN_AGGR_P (fn_fields) = 0;
1830 /* Issue warnings about private constructors and such. If there are
1831 no methods, then some public defaults are generated. */
1832 maybe_warn_about_overly_private_class (t);
1834 /* The type conversion ops have to live at the front of the vec, so we
1836 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1837 VEC_iterate (tree, method_vec, slot, fn_fields);
1839 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1842 qsort (VEC_address (tree, method_vec) + slot,
1843 len-slot, sizeof (tree), method_name_cmp);
1846 /* Make BINFO's vtable have N entries, including RTTI entries,
1847 vbase and vcall offsets, etc. Set its type and call the back end
1851 layout_vtable_decl (tree binfo, int n)
1856 atype = build_array_of_n_type (vtable_entry_type, n);
1857 layout_type (atype);
1859 /* We may have to grow the vtable. */
1860 vtable = get_vtbl_decl_for_binfo (binfo);
1861 if (!same_type_p (TREE_TYPE (vtable), atype))
1863 TREE_TYPE (vtable) = atype;
1864 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1865 layout_decl (vtable, 0);
1869 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1870 have the same signature. */
1873 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1875 /* One destructor overrides another if they are the same kind of
1877 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1878 && special_function_p (base_fndecl) == special_function_p (fndecl))
1880 /* But a non-destructor never overrides a destructor, nor vice
1881 versa, nor do different kinds of destructors override
1882 one-another. For example, a complete object destructor does not
1883 override a deleting destructor. */
1884 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1887 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1888 || (DECL_CONV_FN_P (fndecl)
1889 && DECL_CONV_FN_P (base_fndecl)
1890 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1891 DECL_CONV_FN_TYPE (base_fndecl))))
1893 tree types, base_types;
1894 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1895 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1896 if ((cp_type_quals (TREE_TYPE (TREE_VALUE (base_types)))
1897 == cp_type_quals (TREE_TYPE (TREE_VALUE (types))))
1898 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1904 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1908 base_derived_from (tree derived, tree base)
1912 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1914 if (probe == derived)
1916 else if (BINFO_VIRTUAL_P (probe))
1917 /* If we meet a virtual base, we can't follow the inheritance
1918 any more. See if the complete type of DERIVED contains
1919 such a virtual base. */
1920 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1926 typedef struct find_final_overrider_data_s {
1927 /* The function for which we are trying to find a final overrider. */
1929 /* The base class in which the function was declared. */
1930 tree declaring_base;
1931 /* The candidate overriders. */
1933 /* Path to most derived. */
1934 VEC(tree,heap) *path;
1935 } find_final_overrider_data;
1937 /* Add the overrider along the current path to FFOD->CANDIDATES.
1938 Returns true if an overrider was found; false otherwise. */
1941 dfs_find_final_overrider_1 (tree binfo,
1942 find_final_overrider_data *ffod,
1947 /* If BINFO is not the most derived type, try a more derived class.
1948 A definition there will overrider a definition here. */
1952 if (dfs_find_final_overrider_1
1953 (VEC_index (tree, ffod->path, depth), ffod, depth))
1957 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1960 tree *candidate = &ffod->candidates;
1962 /* Remove any candidates overridden by this new function. */
1965 /* If *CANDIDATE overrides METHOD, then METHOD
1966 cannot override anything else on the list. */
1967 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1969 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1970 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1971 *candidate = TREE_CHAIN (*candidate);
1973 candidate = &TREE_CHAIN (*candidate);
1976 /* Add the new function. */
1977 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1984 /* Called from find_final_overrider via dfs_walk. */
1987 dfs_find_final_overrider_pre (tree binfo, void *data)
1989 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1991 if (binfo == ffod->declaring_base)
1992 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1993 VEC_safe_push (tree, heap, ffod->path, binfo);
1999 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
2001 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
2002 VEC_pop (tree, ffod->path);
2007 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
2008 FN and whose TREE_VALUE is the binfo for the base where the
2009 overriding occurs. BINFO (in the hierarchy dominated by the binfo
2010 DERIVED) is the base object in which FN is declared. */
2013 find_final_overrider (tree derived, tree binfo, tree fn)
2015 find_final_overrider_data ffod;
2017 /* Getting this right is a little tricky. This is valid:
2019 struct S { virtual void f (); };
2020 struct T { virtual void f (); };
2021 struct U : public S, public T { };
2023 even though calling `f' in `U' is ambiguous. But,
2025 struct R { virtual void f(); };
2026 struct S : virtual public R { virtual void f (); };
2027 struct T : virtual public R { virtual void f (); };
2028 struct U : public S, public T { };
2030 is not -- there's no way to decide whether to put `S::f' or
2031 `T::f' in the vtable for `R'.
2033 The solution is to look at all paths to BINFO. If we find
2034 different overriders along any two, then there is a problem. */
2035 if (DECL_THUNK_P (fn))
2036 fn = THUNK_TARGET (fn);
2038 /* Determine the depth of the hierarchy. */
2040 ffod.declaring_base = binfo;
2041 ffod.candidates = NULL_TREE;
2042 ffod.path = VEC_alloc (tree, heap, 30);
2044 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2045 dfs_find_final_overrider_post, &ffod);
2047 VEC_free (tree, heap, ffod.path);
2049 /* If there was no winner, issue an error message. */
2050 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2051 return error_mark_node;
2053 return ffod.candidates;
2056 /* Return the index of the vcall offset for FN when TYPE is used as a
2060 get_vcall_index (tree fn, tree type)
2062 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2066 FOR_EACH_VEC_ELT (tree_pair_s, indices, ix, p)
2067 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2068 || same_signature_p (fn, p->purpose))
2071 /* There should always be an appropriate index. */
2075 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2076 dominated by T. FN is the old function; VIRTUALS points to the
2077 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2078 of that entry in the list. */
2081 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2089 tree overrider_fn, overrider_target;
2090 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2091 tree over_return, base_return;
2094 /* Find the nearest primary base (possibly binfo itself) which defines
2095 this function; this is the class the caller will convert to when
2096 calling FN through BINFO. */
2097 for (b = binfo; ; b = get_primary_binfo (b))
2100 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2103 /* The nearest definition is from a lost primary. */
2104 if (BINFO_LOST_PRIMARY_P (b))
2109 /* Find the final overrider. */
2110 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2111 if (overrider == error_mark_node)
2113 error ("no unique final overrider for %qD in %qT", target_fn, t);
2116 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2118 /* Check for adjusting covariant return types. */
2119 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2120 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2122 if (POINTER_TYPE_P (over_return)
2123 && TREE_CODE (over_return) == TREE_CODE (base_return)
2124 && CLASS_TYPE_P (TREE_TYPE (over_return))
2125 && CLASS_TYPE_P (TREE_TYPE (base_return))
2126 /* If the overrider is invalid, don't even try. */
2127 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2129 /* If FN is a covariant thunk, we must figure out the adjustment
2130 to the final base FN was converting to. As OVERRIDER_TARGET might
2131 also be converting to the return type of FN, we have to
2132 combine the two conversions here. */
2133 tree fixed_offset, virtual_offset;
2135 over_return = TREE_TYPE (over_return);
2136 base_return = TREE_TYPE (base_return);
2138 if (DECL_THUNK_P (fn))
2140 gcc_assert (DECL_RESULT_THUNK_P (fn));
2141 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2142 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2145 fixed_offset = virtual_offset = NULL_TREE;
2148 /* Find the equivalent binfo within the return type of the
2149 overriding function. We will want the vbase offset from
2151 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2153 else if (!same_type_ignoring_top_level_qualifiers_p
2154 (over_return, base_return))
2156 /* There was no existing virtual thunk (which takes
2157 precedence). So find the binfo of the base function's
2158 return type within the overriding function's return type.
2159 We cannot call lookup base here, because we're inside a
2160 dfs_walk, and will therefore clobber the BINFO_MARKED
2161 flags. Fortunately we know the covariancy is valid (it
2162 has already been checked), so we can just iterate along
2163 the binfos, which have been chained in inheritance graph
2164 order. Of course it is lame that we have to repeat the
2165 search here anyway -- we should really be caching pieces
2166 of the vtable and avoiding this repeated work. */
2167 tree thunk_binfo, base_binfo;
2169 /* Find the base binfo within the overriding function's
2170 return type. We will always find a thunk_binfo, except
2171 when the covariancy is invalid (which we will have
2172 already diagnosed). */
2173 for (base_binfo = TYPE_BINFO (base_return),
2174 thunk_binfo = TYPE_BINFO (over_return);
2176 thunk_binfo = TREE_CHAIN (thunk_binfo))
2177 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2178 BINFO_TYPE (base_binfo)))
2181 /* See if virtual inheritance is involved. */
2182 for (virtual_offset = thunk_binfo;
2184 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2185 if (BINFO_VIRTUAL_P (virtual_offset))
2189 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2191 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2195 /* We convert via virtual base. Adjust the fixed
2196 offset to be from there. */
2198 size_diffop (offset,
2200 BINFO_OFFSET (virtual_offset)));
2203 /* There was an existing fixed offset, this must be
2204 from the base just converted to, and the base the
2205 FN was thunking to. */
2206 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2208 fixed_offset = offset;
2212 if (fixed_offset || virtual_offset)
2213 /* Replace the overriding function with a covariant thunk. We
2214 will emit the overriding function in its own slot as
2216 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2217 fixed_offset, virtual_offset);
2220 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2221 !DECL_THUNK_P (fn));
2223 /* If we need a covariant thunk, then we may need to adjust first_defn.
2224 The ABI specifies that the thunks emitted with a function are
2225 determined by which bases the function overrides, so we need to be
2226 sure that we're using a thunk for some overridden base; even if we
2227 know that the necessary this adjustment is zero, there may not be an
2228 appropriate zero-this-adjusment thunk for us to use since thunks for
2229 overriding virtual bases always use the vcall offset.
2231 Furthermore, just choosing any base that overrides this function isn't
2232 quite right, as this slot won't be used for calls through a type that
2233 puts a covariant thunk here. Calling the function through such a type
2234 will use a different slot, and that slot is the one that determines
2235 the thunk emitted for that base.
2237 So, keep looking until we find the base that we're really overriding
2238 in this slot: the nearest primary base that doesn't use a covariant
2239 thunk in this slot. */
2240 if (overrider_target != overrider_fn)
2242 if (BINFO_TYPE (b) == DECL_CONTEXT (overrider_target))
2243 /* We already know that the overrider needs a covariant thunk. */
2244 b = get_primary_binfo (b);
2245 for (; ; b = get_primary_binfo (b))
2247 tree main_binfo = TYPE_BINFO (BINFO_TYPE (b));
2248 tree bv = chain_index (ix, BINFO_VIRTUALS (main_binfo));
2249 if (!DECL_THUNK_P (TREE_VALUE (bv)))
2251 if (BINFO_LOST_PRIMARY_P (b))
2257 /* Assume that we will produce a thunk that convert all the way to
2258 the final overrider, and not to an intermediate virtual base. */
2259 virtual_base = NULL_TREE;
2261 /* See if we can convert to an intermediate virtual base first, and then
2262 use the vcall offset located there to finish the conversion. */
2263 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2265 /* If we find the final overrider, then we can stop
2267 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2268 BINFO_TYPE (TREE_VALUE (overrider))))
2271 /* If we find a virtual base, and we haven't yet found the
2272 overrider, then there is a virtual base between the
2273 declaring base (first_defn) and the final overrider. */
2274 if (BINFO_VIRTUAL_P (b))
2281 /* Compute the constant adjustment to the `this' pointer. The
2282 `this' pointer, when this function is called, will point at BINFO
2283 (or one of its primary bases, which are at the same offset). */
2285 /* The `this' pointer needs to be adjusted from the declaration to
2286 the nearest virtual base. */
2287 delta = size_diffop_loc (input_location,
2288 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2289 convert (ssizetype, BINFO_OFFSET (first_defn)));
2291 /* If the nearest definition is in a lost primary, we don't need an
2292 entry in our vtable. Except possibly in a constructor vtable,
2293 if we happen to get our primary back. In that case, the offset
2294 will be zero, as it will be a primary base. */
2295 delta = size_zero_node;
2297 /* The `this' pointer needs to be adjusted from pointing to
2298 BINFO to pointing at the base where the final overrider
2300 delta = size_diffop_loc (input_location,
2302 BINFO_OFFSET (TREE_VALUE (overrider))),
2303 convert (ssizetype, BINFO_OFFSET (binfo)));
2305 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2308 BV_VCALL_INDEX (*virtuals)
2309 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2311 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2314 BV_LOST_PRIMARY (*virtuals) = true;
2317 /* Called from modify_all_vtables via dfs_walk. */
2320 dfs_modify_vtables (tree binfo, void* data)
2322 tree t = (tree) data;
2327 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2328 /* A base without a vtable needs no modification, and its bases
2329 are uninteresting. */
2330 return dfs_skip_bases;
2332 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2333 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2334 /* Don't do the primary vtable, if it's new. */
2337 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2338 /* There's no need to modify the vtable for a non-virtual primary
2339 base; we're not going to use that vtable anyhow. We do still
2340 need to do this for virtual primary bases, as they could become
2341 non-primary in a construction vtable. */
2344 make_new_vtable (t, binfo);
2346 /* Now, go through each of the virtual functions in the virtual
2347 function table for BINFO. Find the final overrider, and update
2348 the BINFO_VIRTUALS list appropriately. */
2349 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2350 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2352 ix++, virtuals = TREE_CHAIN (virtuals),
2353 old_virtuals = TREE_CHAIN (old_virtuals))
2354 update_vtable_entry_for_fn (t,
2356 BV_FN (old_virtuals),
2362 /* Update all of the primary and secondary vtables for T. Create new
2363 vtables as required, and initialize their RTTI information. Each
2364 of the functions in VIRTUALS is declared in T and may override a
2365 virtual function from a base class; find and modify the appropriate
2366 entries to point to the overriding functions. Returns a list, in
2367 declaration order, of the virtual functions that are declared in T,
2368 but do not appear in the primary base class vtable, and which
2369 should therefore be appended to the end of the vtable for T. */
2372 modify_all_vtables (tree t, tree virtuals)
2374 tree binfo = TYPE_BINFO (t);
2377 /* Update all of the vtables. */
2378 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2380 /* Add virtual functions not already in our primary vtable. These
2381 will be both those introduced by this class, and those overridden
2382 from secondary bases. It does not include virtuals merely
2383 inherited from secondary bases. */
2384 for (fnsp = &virtuals; *fnsp; )
2386 tree fn = TREE_VALUE (*fnsp);
2388 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2389 || DECL_VINDEX (fn) == error_mark_node)
2391 /* We don't need to adjust the `this' pointer when
2392 calling this function. */
2393 BV_DELTA (*fnsp) = integer_zero_node;
2394 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2396 /* This is a function not already in our vtable. Keep it. */
2397 fnsp = &TREE_CHAIN (*fnsp);
2400 /* We've already got an entry for this function. Skip it. */
2401 *fnsp = TREE_CHAIN (*fnsp);
2407 /* Get the base virtual function declarations in T that have the
2411 get_basefndecls (tree name, tree t)
2414 tree base_fndecls = NULL_TREE;
2415 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2418 /* Find virtual functions in T with the indicated NAME. */
2419 i = lookup_fnfields_1 (t, name);
2421 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2423 methods = OVL_NEXT (methods))
2425 tree method = OVL_CURRENT (methods);
2427 if (TREE_CODE (method) == FUNCTION_DECL
2428 && DECL_VINDEX (method))
2429 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2433 return base_fndecls;
2435 for (i = 0; i < n_baseclasses; i++)
2437 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2438 base_fndecls = chainon (get_basefndecls (name, basetype),
2442 return base_fndecls;
2445 /* If this declaration supersedes the declaration of
2446 a method declared virtual in the base class, then
2447 mark this field as being virtual as well. */
2450 check_for_override (tree decl, tree ctype)
2452 bool overrides_found = false;
2453 if (TREE_CODE (decl) == TEMPLATE_DECL)
2454 /* In [temp.mem] we have:
2456 A specialization of a member function template does not
2457 override a virtual function from a base class. */
2459 if ((DECL_DESTRUCTOR_P (decl)
2460 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2461 || DECL_CONV_FN_P (decl))
2462 && look_for_overrides (ctype, decl)
2463 && !DECL_STATIC_FUNCTION_P (decl))
2464 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2465 the error_mark_node so that we know it is an overriding
2468 DECL_VINDEX (decl) = decl;
2469 overrides_found = true;
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;
2477 if (DECL_DESTRUCTOR_P (decl))
2478 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (ctype) = true;
2480 else if (DECL_FINAL_P (decl))
2481 error ("%q+#D marked final, but is not virtual", decl);
2482 if (DECL_OVERRIDE_P (decl) && !overrides_found)
2483 error ("%q+#D marked override, but does not override", decl);
2486 /* Warn about hidden virtual functions that are not overridden in t.
2487 We know that constructors and destructors don't apply. */
2490 warn_hidden (tree t)
2492 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2496 /* We go through each separately named virtual function. */
2497 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2498 VEC_iterate (tree, method_vec, i, fns);
2509 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2510 have the same name. Figure out what name that is. */
2511 name = DECL_NAME (OVL_CURRENT (fns));
2512 /* There are no possibly hidden functions yet. */
2513 base_fndecls = NULL_TREE;
2514 /* Iterate through all of the base classes looking for possibly
2515 hidden functions. */
2516 for (binfo = TYPE_BINFO (t), j = 0;
2517 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2519 tree basetype = BINFO_TYPE (base_binfo);
2520 base_fndecls = chainon (get_basefndecls (name, basetype),
2524 /* If there are no functions to hide, continue. */
2528 /* Remove any overridden functions. */
2529 for (fn = fns; fn; fn = OVL_NEXT (fn))
2531 fndecl = OVL_CURRENT (fn);
2532 if (DECL_VINDEX (fndecl))
2534 tree *prev = &base_fndecls;
2537 /* If the method from the base class has the same
2538 signature as the method from the derived class, it
2539 has been overridden. */
2540 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2541 *prev = TREE_CHAIN (*prev);
2543 prev = &TREE_CHAIN (*prev);
2547 /* Now give a warning for all base functions without overriders,
2548 as they are hidden. */
2549 while (base_fndecls)
2551 /* Here we know it is a hider, and no overrider exists. */
2552 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2553 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2554 base_fndecls = TREE_CHAIN (base_fndecls);
2559 /* Check for things that are invalid. There are probably plenty of other
2560 things we should check for also. */
2563 finish_struct_anon (tree t)
2567 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
2569 if (TREE_STATIC (field))
2571 if (TREE_CODE (field) != FIELD_DECL)
2574 if (DECL_NAME (field) == NULL_TREE
2575 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2577 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2578 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2579 for (; elt; elt = DECL_CHAIN (elt))
2581 /* We're generally only interested in entities the user
2582 declared, but we also find nested classes by noticing
2583 the TYPE_DECL that we create implicitly. You're
2584 allowed to put one anonymous union inside another,
2585 though, so we explicitly tolerate that. We use
2586 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2587 we also allow unnamed types used for defining fields. */
2588 if (DECL_ARTIFICIAL (elt)
2589 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2590 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2593 if (TREE_CODE (elt) != FIELD_DECL)
2596 permerror (input_location, "%q+#D invalid; an anonymous union can "
2597 "only have non-static data members", elt);
2599 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2600 "only have non-static data members", elt);
2604 if (TREE_PRIVATE (elt))
2607 permerror (input_location, "private member %q+#D in anonymous union", elt);
2609 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2611 else if (TREE_PROTECTED (elt))
2614 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2616 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2619 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2620 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2626 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2627 will be used later during class template instantiation.
2628 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2629 a non-static member data (FIELD_DECL), a member function
2630 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2631 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2632 When FRIEND_P is nonzero, T is either a friend class
2633 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2634 (FUNCTION_DECL, TEMPLATE_DECL). */
2637 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2639 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2640 if (CLASSTYPE_TEMPLATE_INFO (type))
2641 CLASSTYPE_DECL_LIST (type)
2642 = tree_cons (friend_p ? NULL_TREE : type,
2643 t, CLASSTYPE_DECL_LIST (type));
2646 /* This function is called from declare_virt_assop_and_dtor via
2649 DATA is a type that direcly or indirectly inherits the base
2650 represented by BINFO. If BINFO contains a virtual assignment [copy
2651 assignment or move assigment] operator or a virtual constructor,
2652 declare that function in DATA if it hasn't been already declared. */
2655 dfs_declare_virt_assop_and_dtor (tree binfo, void *data)
2657 tree bv, fn, t = (tree)data;
2658 tree opname = ansi_assopname (NOP_EXPR);
2660 gcc_assert (t && CLASS_TYPE_P (t));
2661 gcc_assert (binfo && TREE_CODE (binfo) == TREE_BINFO);
2663 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2664 /* A base without a vtable needs no modification, and its bases
2665 are uninteresting. */
2666 return dfs_skip_bases;
2668 if (BINFO_PRIMARY_P (binfo))
2669 /* If this is a primary base, then we have already looked at the
2670 virtual functions of its vtable. */
2673 for (bv = BINFO_VIRTUALS (binfo); bv; bv = TREE_CHAIN (bv))
2677 if (DECL_NAME (fn) == opname)
2679 if (CLASSTYPE_LAZY_COPY_ASSIGN (t))
2680 lazily_declare_fn (sfk_copy_assignment, t);
2681 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
2682 lazily_declare_fn (sfk_move_assignment, t);
2684 else if (DECL_DESTRUCTOR_P (fn)
2685 && CLASSTYPE_LAZY_DESTRUCTOR (t))
2686 lazily_declare_fn (sfk_destructor, t);
2692 /* If the class type T has a direct or indirect base that contains a
2693 virtual assignment operator or a virtual destructor, declare that
2694 function in T if it hasn't been already declared. */
2697 declare_virt_assop_and_dtor (tree t)
2699 if (!(TYPE_POLYMORPHIC_P (t)
2700 && (CLASSTYPE_LAZY_COPY_ASSIGN (t)
2701 || CLASSTYPE_LAZY_MOVE_ASSIGN (t)
2702 || CLASSTYPE_LAZY_DESTRUCTOR (t))))
2705 dfs_walk_all (TYPE_BINFO (t),
2706 dfs_declare_virt_assop_and_dtor,
2710 /* Create default constructors, assignment operators, and so forth for
2711 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2712 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2713 the class cannot have a default constructor, copy constructor
2714 taking a const reference argument, or an assignment operator taking
2715 a const reference, respectively. */
2718 add_implicitly_declared_members (tree t,
2719 int cant_have_const_cctor,
2720 int cant_have_const_assignment)
2723 if (!CLASSTYPE_DESTRUCTORS (t))
2725 /* In general, we create destructors lazily. */
2726 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2728 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2729 && TYPE_FOR_JAVA (t))
2730 /* But if this is a Java class, any non-trivial destructor is
2731 invalid, even if compiler-generated. Therefore, if the
2732 destructor is non-trivial we create it now. */
2733 lazily_declare_fn (sfk_destructor, t);
2738 If there is no user-declared constructor for a class, a default
2739 constructor is implicitly declared. */
2740 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2742 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2743 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2744 if (cxx_dialect >= cxx0x)
2745 TYPE_HAS_CONSTEXPR_CTOR (t)
2746 = synthesized_default_constructor_is_constexpr (t);
2751 If a class definition does not explicitly declare a copy
2752 constructor, one is declared implicitly. */
2753 if (! TYPE_HAS_COPY_CTOR (t) && ! TYPE_FOR_JAVA (t)
2754 && !type_has_move_constructor (t))
2756 TYPE_HAS_COPY_CTOR (t) = 1;
2757 TYPE_HAS_CONST_COPY_CTOR (t) = !cant_have_const_cctor;
2758 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2759 if (cxx_dialect >= cxx0x)
2760 CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
2763 /* If there is no assignment operator, one will be created if and
2764 when it is needed. For now, just record whether or not the type
2765 of the parameter to the assignment operator will be a const or
2766 non-const reference. */
2767 if (!TYPE_HAS_COPY_ASSIGN (t) && !TYPE_FOR_JAVA (t)
2768 && !type_has_move_assign (t))
2770 TYPE_HAS_COPY_ASSIGN (t) = 1;
2771 TYPE_HAS_CONST_COPY_ASSIGN (t) = !cant_have_const_assignment;
2772 CLASSTYPE_LAZY_COPY_ASSIGN (t) = 1;
2773 if (cxx_dialect >= cxx0x)
2774 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 1;
2777 /* We can't be lazy about declaring functions that might override
2778 a virtual function from a base class. */
2779 declare_virt_assop_and_dtor (t);
2782 /* Subroutine of finish_struct_1. Recursively count the number of fields
2783 in TYPE, including anonymous union members. */
2786 count_fields (tree fields)
2790 for (x = fields; x; x = DECL_CHAIN (x))
2792 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2793 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2800 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2801 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2804 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2807 for (x = fields; x; x = DECL_CHAIN (x))
2809 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2810 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2812 field_vec->elts[idx++] = x;
2817 /* FIELD is a bit-field. We are finishing the processing for its
2818 enclosing type. Issue any appropriate messages and set appropriate
2819 flags. Returns false if an error has been diagnosed. */
2822 check_bitfield_decl (tree field)
2824 tree type = TREE_TYPE (field);
2827 /* Extract the declared width of the bitfield, which has been
2828 temporarily stashed in DECL_INITIAL. */
2829 w = DECL_INITIAL (field);
2830 gcc_assert (w != NULL_TREE);
2831 /* Remove the bit-field width indicator so that the rest of the
2832 compiler does not treat that value as an initializer. */
2833 DECL_INITIAL (field) = NULL_TREE;
2835 /* Detect invalid bit-field type. */
2836 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2838 error ("bit-field %q+#D with non-integral type", field);
2839 w = error_mark_node;
2843 location_t loc = input_location;
2844 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2847 /* detect invalid field size. */
2848 input_location = DECL_SOURCE_LOCATION (field);
2849 w = cxx_constant_value (w);
2850 input_location = loc;
2852 if (TREE_CODE (w) != INTEGER_CST)
2854 error ("bit-field %q+D width not an integer constant", field);
2855 w = error_mark_node;
2857 else if (tree_int_cst_sgn (w) < 0)
2859 error ("negative width in bit-field %q+D", field);
2860 w = error_mark_node;
2862 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2864 error ("zero width for bit-field %q+D", field);
2865 w = error_mark_node;
2867 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2868 && TREE_CODE (type) != ENUMERAL_TYPE
2869 && TREE_CODE (type) != BOOLEAN_TYPE)
2870 warning (0, "width of %q+D exceeds its type", field);
2871 else if (TREE_CODE (type) == ENUMERAL_TYPE
2872 && (0 > (compare_tree_int
2873 (w, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type))))))
2874 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2877 if (w != error_mark_node)
2879 DECL_SIZE (field) = convert (bitsizetype, w);
2880 DECL_BIT_FIELD (field) = 1;
2885 /* Non-bit-fields are aligned for their type. */
2886 DECL_BIT_FIELD (field) = 0;
2887 CLEAR_DECL_C_BIT_FIELD (field);
2892 /* FIELD is a non bit-field. We are finishing the processing for its
2893 enclosing type T. Issue any appropriate messages and set appropriate
2897 check_field_decl (tree field,
2899 int* cant_have_const_ctor,
2900 int* no_const_asn_ref,
2901 int* any_default_members)
2903 tree type = strip_array_types (TREE_TYPE (field));
2905 /* In C++98 an anonymous union cannot contain any fields which would change
2906 the settings of CANT_HAVE_CONST_CTOR and friends. */
2907 if (ANON_UNION_TYPE_P (type) && cxx_dialect < cxx0x)
2909 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2910 structs. So, we recurse through their fields here. */
2911 else if (ANON_AGGR_TYPE_P (type))
2915 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2916 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2917 check_field_decl (fields, t, cant_have_const_ctor,
2918 no_const_asn_ref, any_default_members);
2920 /* Check members with class type for constructors, destructors,
2922 else if (CLASS_TYPE_P (type))
2924 /* Never let anything with uninheritable virtuals
2925 make it through without complaint. */
2926 abstract_virtuals_error (field, type);
2928 if (TREE_CODE (t) == UNION_TYPE && cxx_dialect < cxx0x)
2931 int oldcount = errorcount;
2932 if (TYPE_NEEDS_CONSTRUCTING (type))
2933 error ("member %q+#D with constructor not allowed in union",
2935 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2936 error ("member %q+#D with destructor not allowed in union", field);
2937 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
2938 error ("member %q+#D with copy assignment operator not allowed in union",
2940 if (!warned && errorcount > oldcount)
2942 inform (DECL_SOURCE_LOCATION (field), "unrestricted unions "
2943 "only available with -std=c++0x or -std=gnu++0x");
2949 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2950 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2951 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2952 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
2953 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type)
2954 || !TYPE_HAS_COPY_ASSIGN (type));
2955 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type)
2956 || !TYPE_HAS_COPY_CTOR (type));
2957 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type);
2958 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type);
2959 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type)
2960 || TYPE_HAS_COMPLEX_DFLT (type));
2963 if (TYPE_HAS_COPY_CTOR (type)
2964 && !TYPE_HAS_CONST_COPY_CTOR (type))
2965 *cant_have_const_ctor = 1;
2967 if (TYPE_HAS_COPY_ASSIGN (type)
2968 && !TYPE_HAS_CONST_COPY_ASSIGN (type))
2969 *no_const_asn_ref = 1;
2971 if (DECL_INITIAL (field) != NULL_TREE)
2973 /* `build_class_init_list' does not recognize
2975 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2976 error ("multiple fields in union %qT initialized", t);
2977 *any_default_members = 1;
2981 /* Check the data members (both static and non-static), class-scoped
2982 typedefs, etc., appearing in the declaration of T. Issue
2983 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2984 declaration order) of access declarations; each TREE_VALUE in this
2985 list is a USING_DECL.
2987 In addition, set the following flags:
2990 The class is empty, i.e., contains no non-static data members.
2992 CANT_HAVE_CONST_CTOR_P
2993 This class cannot have an implicitly generated copy constructor
2994 taking a const reference.
2996 CANT_HAVE_CONST_ASN_REF
2997 This class cannot have an implicitly generated assignment
2998 operator taking a const reference.
3000 All of these flags should be initialized before calling this
3003 Returns a pointer to the end of the TYPE_FIELDs chain; additional
3004 fields can be added by adding to this chain. */
3007 check_field_decls (tree t, tree *access_decls,
3008 int *cant_have_const_ctor_p,
3009 int *no_const_asn_ref_p)
3014 int any_default_members;
3016 int field_access = -1;
3018 /* Assume there are no access declarations. */
3019 *access_decls = NULL_TREE;
3020 /* Assume this class has no pointer members. */
3021 has_pointers = false;
3022 /* Assume none of the members of this class have default
3024 any_default_members = 0;
3026 for (field = &TYPE_FIELDS (t); *field; field = next)
3029 tree type = TREE_TYPE (x);
3030 int this_field_access;
3032 next = &DECL_CHAIN (x);
3034 if (TREE_CODE (x) == USING_DECL)
3036 /* Prune the access declaration from the list of fields. */
3037 *field = DECL_CHAIN (x);
3039 /* Save the access declarations for our caller. */
3040 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
3042 /* Since we've reset *FIELD there's no reason to skip to the
3048 if (TREE_CODE (x) == TYPE_DECL
3049 || TREE_CODE (x) == TEMPLATE_DECL)
3052 /* If we've gotten this far, it's a data member, possibly static,
3053 or an enumerator. */
3054 DECL_CONTEXT (x) = t;
3056 /* When this goes into scope, it will be a non-local reference. */
3057 DECL_NONLOCAL (x) = 1;
3059 if (TREE_CODE (t) == UNION_TYPE)
3063 If a union contains a static data member, or a member of
3064 reference type, the program is ill-formed. */
3065 if (TREE_CODE (x) == VAR_DECL)
3067 error ("%q+D may not be static because it is a member of a union", x);
3070 if (TREE_CODE (type) == REFERENCE_TYPE)
3072 error ("%q+D may not have reference type %qT because"
3073 " it is a member of a union",
3079 /* Perform error checking that did not get done in
3081 if (TREE_CODE (type) == FUNCTION_TYPE)
3083 error ("field %q+D invalidly declared function type", x);
3084 type = build_pointer_type (type);
3085 TREE_TYPE (x) = type;
3087 else if (TREE_CODE (type) == METHOD_TYPE)
3089 error ("field %q+D invalidly declared method type", x);
3090 type = build_pointer_type (type);
3091 TREE_TYPE (x) = type;
3094 if (type == error_mark_node)
3097 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
3100 /* Now it can only be a FIELD_DECL. */
3102 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3103 CLASSTYPE_NON_AGGREGATE (t) = 1;
3105 /* If at least one non-static data member is non-literal, the whole
3106 class becomes non-literal. */
3107 if (!literal_type_p (type))
3108 CLASSTYPE_LITERAL_P (t) = false;
3110 /* A standard-layout class is a class that:
3112 has the same access control (Clause 11) for all non-static data members,
3114 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3115 if (field_access == -1)
3116 field_access = this_field_access;
3117 else if (this_field_access != field_access)
3118 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3120 /* If this is of reference type, check if it needs an init. */
3121 if (TREE_CODE (type) == REFERENCE_TYPE)
3123 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3124 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3125 if (DECL_INITIAL (x) == NULL_TREE)
3126 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3128 /* ARM $12.6.2: [A member initializer list] (or, for an
3129 aggregate, initialization by a brace-enclosed list) is the
3130 only way to initialize nonstatic const and reference
3132 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3133 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3136 type = strip_array_types (type);
3138 if (TYPE_PACKED (t))
3140 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3144 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3148 else if (DECL_C_BIT_FIELD (x)
3149 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3150 DECL_PACKED (x) = 1;
3153 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3154 /* We don't treat zero-width bitfields as making a class
3159 /* The class is non-empty. */
3160 CLASSTYPE_EMPTY_P (t) = 0;
3161 /* The class is not even nearly empty. */
3162 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3163 /* If one of the data members contains an empty class,
3165 if (CLASS_TYPE_P (type)
3166 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3167 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3170 /* This is used by -Weffc++ (see below). Warn only for pointers
3171 to members which might hold dynamic memory. So do not warn
3172 for pointers to functions or pointers to members. */
3173 if (TYPE_PTR_P (type)
3174 && !TYPE_PTRFN_P (type)
3175 && !TYPE_PTR_TO_MEMBER_P (type))
3176 has_pointers = true;
3178 if (CLASS_TYPE_P (type))
3180 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3181 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3182 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3183 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3186 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3187 CLASSTYPE_HAS_MUTABLE (t) = 1;
3189 if (! layout_pod_type_p (type))
3190 /* DR 148 now allows pointers to members (which are POD themselves),
3191 to be allowed in POD structs. */
3192 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3194 if (!std_layout_type_p (type))
3195 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3197 if (! zero_init_p (type))
3198 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3200 /* We set DECL_C_BIT_FIELD in grokbitfield.
3201 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3202 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3203 check_field_decl (x, t,
3204 cant_have_const_ctor_p,
3206 &any_default_members);
3208 /* If any field is const, the structure type is pseudo-const. */
3209 if (CP_TYPE_CONST_P (type))
3211 C_TYPE_FIELDS_READONLY (t) = 1;
3212 if (DECL_INITIAL (x) == NULL_TREE)
3213 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3215 /* ARM $12.6.2: [A member initializer list] (or, for an
3216 aggregate, initialization by a brace-enclosed list) is the
3217 only way to initialize nonstatic const and reference
3219 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3220 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3222 /* A field that is pseudo-const makes the structure likewise. */
3223 else if (CLASS_TYPE_P (type))
3225 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3226 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3227 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3228 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3231 /* Core issue 80: A nonstatic data member is required to have a
3232 different name from the class iff the class has a
3233 user-declared constructor. */
3234 if (constructor_name_p (DECL_NAME (x), t)
3235 && TYPE_HAS_USER_CONSTRUCTOR (t))
3236 permerror (input_location, "field %q+#D with same name as class", x);
3239 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3240 it should also define a copy constructor and an assignment operator to
3241 implement the correct copy semantic (deep vs shallow, etc.). As it is
3242 not feasible to check whether the constructors do allocate dynamic memory
3243 and store it within members, we approximate the warning like this:
3245 -- Warn only if there are members which are pointers
3246 -- Warn only if there is a non-trivial constructor (otherwise,
3247 there cannot be memory allocated).
3248 -- Warn only if there is a non-trivial destructor. We assume that the
3249 user at least implemented the cleanup correctly, and a destructor
3250 is needed to free dynamic memory.
3252 This seems enough for practical purposes. */
3255 && TYPE_HAS_USER_CONSTRUCTOR (t)
3256 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3257 && !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
3259 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3261 if (! TYPE_HAS_COPY_CTOR (t))
3263 warning (OPT_Weffc__,
3264 " but does not override %<%T(const %T&)%>", t, t);
3265 if (!TYPE_HAS_COPY_ASSIGN (t))
3266 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3268 else if (! TYPE_HAS_COPY_ASSIGN (t))
3269 warning (OPT_Weffc__,
3270 " but does not override %<operator=(const %T&)%>", t);
3273 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3275 TYPE_PACKED (t) = 0;
3277 /* Check anonymous struct/anonymous union fields. */
3278 finish_struct_anon (t);
3280 /* We've built up the list of access declarations in reverse order.
3282 *access_decls = nreverse (*access_decls);
3285 /* If TYPE is an empty class type, records its OFFSET in the table of
3289 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3293 if (!is_empty_class (type))
3296 /* Record the location of this empty object in OFFSETS. */
3297 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3299 n = splay_tree_insert (offsets,
3300 (splay_tree_key) offset,
3301 (splay_tree_value) NULL_TREE);
3302 n->value = ((splay_tree_value)
3303 tree_cons (NULL_TREE,
3310 /* Returns nonzero if TYPE is an empty class type and there is
3311 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3314 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3319 if (!is_empty_class (type))
3322 /* Record the location of this empty object in OFFSETS. */
3323 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3327 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3328 if (same_type_p (TREE_VALUE (t), type))
3334 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3335 F for every subobject, passing it the type, offset, and table of
3336 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3339 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3340 than MAX_OFFSET will not be walked.
3342 If F returns a nonzero value, the traversal ceases, and that value
3343 is returned. Otherwise, returns zero. */
3346 walk_subobject_offsets (tree type,
3347 subobject_offset_fn f,
3354 tree type_binfo = NULL_TREE;
3356 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3358 if (max_offset && INT_CST_LT (max_offset, offset))
3361 if (type == error_mark_node)
3366 if (abi_version_at_least (2))
3368 type = BINFO_TYPE (type);
3371 if (CLASS_TYPE_P (type))
3377 /* Avoid recursing into objects that are not interesting. */
3378 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3381 /* Record the location of TYPE. */
3382 r = (*f) (type, offset, offsets);
3386 /* Iterate through the direct base classes of TYPE. */
3388 type_binfo = TYPE_BINFO (type);
3389 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3393 if (abi_version_at_least (2)
3394 && BINFO_VIRTUAL_P (binfo))
3398 && BINFO_VIRTUAL_P (binfo)
3399 && !BINFO_PRIMARY_P (binfo))
3402 if (!abi_version_at_least (2))
3403 binfo_offset = size_binop (PLUS_EXPR,
3405 BINFO_OFFSET (binfo));
3409 /* We cannot rely on BINFO_OFFSET being set for the base
3410 class yet, but the offsets for direct non-virtual
3411 bases can be calculated by going back to the TYPE. */
3412 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3413 binfo_offset = size_binop (PLUS_EXPR,
3415 BINFO_OFFSET (orig_binfo));
3418 r = walk_subobject_offsets (binfo,
3423 (abi_version_at_least (2)
3424 ? /*vbases_p=*/0 : vbases_p));
3429 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3432 VEC(tree,gc) *vbases;
3434 /* Iterate through the virtual base classes of TYPE. In G++
3435 3.2, we included virtual bases in the direct base class
3436 loop above, which results in incorrect results; the
3437 correct offsets for virtual bases are only known when
3438 working with the most derived type. */
3440 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3441 VEC_iterate (tree, vbases, ix, binfo); ix++)
3443 r = walk_subobject_offsets (binfo,
3445 size_binop (PLUS_EXPR,
3447 BINFO_OFFSET (binfo)),
3456 /* We still have to walk the primary base, if it is
3457 virtual. (If it is non-virtual, then it was walked
3459 tree vbase = get_primary_binfo (type_binfo);
3461 if (vbase && BINFO_VIRTUAL_P (vbase)
3462 && BINFO_PRIMARY_P (vbase)
3463 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3465 r = (walk_subobject_offsets
3467 offsets, max_offset, /*vbases_p=*/0));
3474 /* Iterate through the fields of TYPE. */
3475 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
3476 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3480 if (abi_version_at_least (2))
3481 field_offset = byte_position (field);
3483 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3484 field_offset = DECL_FIELD_OFFSET (field);
3486 r = walk_subobject_offsets (TREE_TYPE (field),
3488 size_binop (PLUS_EXPR,
3498 else if (TREE_CODE (type) == ARRAY_TYPE)
3500 tree element_type = strip_array_types (type);
3501 tree domain = TYPE_DOMAIN (type);
3504 /* Avoid recursing into objects that are not interesting. */
3505 if (!CLASS_TYPE_P (element_type)
3506 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3509 /* Step through each of the elements in the array. */
3510 for (index = size_zero_node;
3511 /* G++ 3.2 had an off-by-one error here. */
3512 (abi_version_at_least (2)
3513 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3514 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3515 index = size_binop (PLUS_EXPR, index, size_one_node))
3517 r = walk_subobject_offsets (TREE_TYPE (type),
3525 offset = size_binop (PLUS_EXPR, offset,
3526 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3527 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3528 there's no point in iterating through the remaining
3529 elements of the array. */
3530 if (max_offset && INT_CST_LT (max_offset, offset))
3538 /* Record all of the empty subobjects of TYPE (either a type or a
3539 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3540 is being placed at OFFSET; otherwise, it is a base class that is
3541 being placed at OFFSET. */
3544 record_subobject_offsets (tree type,
3547 bool is_data_member)
3550 /* If recording subobjects for a non-static data member or a
3551 non-empty base class , we do not need to record offsets beyond
3552 the size of the biggest empty class. Additional data members
3553 will go at the end of the class. Additional base classes will go
3554 either at offset zero (if empty, in which case they cannot
3555 overlap with offsets past the size of the biggest empty class) or
3556 at the end of the class.
3558 However, if we are placing an empty base class, then we must record
3559 all offsets, as either the empty class is at offset zero (where
3560 other empty classes might later be placed) or at the end of the
3561 class (where other objects might then be placed, so other empty
3562 subobjects might later overlap). */
3564 || !is_empty_class (BINFO_TYPE (type)))
3565 max_offset = sizeof_biggest_empty_class;
3567 max_offset = NULL_TREE;
3568 walk_subobject_offsets (type, record_subobject_offset, offset,
3569 offsets, max_offset, is_data_member);
3572 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3573 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3574 virtual bases of TYPE are examined. */
3577 layout_conflict_p (tree type,
3582 splay_tree_node max_node;
3584 /* Get the node in OFFSETS that indicates the maximum offset where
3585 an empty subobject is located. */
3586 max_node = splay_tree_max (offsets);
3587 /* If there aren't any empty subobjects, then there's no point in
3588 performing this check. */
3592 return walk_subobject_offsets (type, check_subobject_offset, offset,
3593 offsets, (tree) (max_node->key),
3597 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3598 non-static data member of the type indicated by RLI. BINFO is the
3599 binfo corresponding to the base subobject, OFFSETS maps offsets to
3600 types already located at those offsets. This function determines
3601 the position of the DECL. */
3604 layout_nonempty_base_or_field (record_layout_info rli,
3609 tree offset = NULL_TREE;
3615 /* For the purposes of determining layout conflicts, we want to
3616 use the class type of BINFO; TREE_TYPE (DECL) will be the
3617 CLASSTYPE_AS_BASE version, which does not contain entries for
3618 zero-sized bases. */
3619 type = TREE_TYPE (binfo);
3624 type = TREE_TYPE (decl);
3628 /* Try to place the field. It may take more than one try if we have
3629 a hard time placing the field without putting two objects of the
3630 same type at the same address. */
3633 struct record_layout_info_s old_rli = *rli;
3635 /* Place this field. */
3636 place_field (rli, decl);
3637 offset = byte_position (decl);
3639 /* We have to check to see whether or not there is already
3640 something of the same type at the offset we're about to use.
3641 For example, consider:
3644 struct T : public S { int i; };
3645 struct U : public S, public T {};
3647 Here, we put S at offset zero in U. Then, we can't put T at
3648 offset zero -- its S component would be at the same address
3649 as the S we already allocated. So, we have to skip ahead.
3650 Since all data members, including those whose type is an
3651 empty class, have nonzero size, any overlap can happen only
3652 with a direct or indirect base-class -- it can't happen with
3654 /* In a union, overlap is permitted; all members are placed at
3656 if (TREE_CODE (rli->t) == UNION_TYPE)
3658 /* G++ 3.2 did not check for overlaps when placing a non-empty
3660 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3662 if (layout_conflict_p (field_p ? type : binfo, offset,
3665 /* Strip off the size allocated to this field. That puts us
3666 at the first place we could have put the field with
3667 proper alignment. */
3670 /* Bump up by the alignment required for the type. */
3672 = size_binop (PLUS_EXPR, rli->bitpos,
3674 ? CLASSTYPE_ALIGN (type)
3675 : TYPE_ALIGN (type)));
3676 normalize_rli (rli);
3679 /* There was no conflict. We're done laying out this field. */
3683 /* Now that we know where it will be placed, update its
3685 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3686 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3687 this point because their BINFO_OFFSET is copied from another
3688 hierarchy. Therefore, we may not need to add the entire
3690 propagate_binfo_offsets (binfo,
3691 size_diffop_loc (input_location,
3692 convert (ssizetype, offset),
3694 BINFO_OFFSET (binfo))));
3697 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3700 empty_base_at_nonzero_offset_p (tree type,
3702 splay_tree offsets ATTRIBUTE_UNUSED)
3704 return is_empty_class (type) && !integer_zerop (offset);
3707 /* Layout the empty base BINFO. EOC indicates the byte currently just
3708 past the end of the class, and should be correctly aligned for a
3709 class of the type indicated by BINFO; OFFSETS gives the offsets of
3710 the empty bases allocated so far. T is the most derived
3711 type. Return nonzero iff we added it at the end. */
3714 layout_empty_base (record_layout_info rli, tree binfo,
3715 tree eoc, splay_tree offsets)
3718 tree basetype = BINFO_TYPE (binfo);
3721 /* This routine should only be used for empty classes. */
3722 gcc_assert (is_empty_class (basetype));
3723 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3725 if (!integer_zerop (BINFO_OFFSET (binfo)))
3727 if (abi_version_at_least (2))
3728 propagate_binfo_offsets
3729 (binfo, size_diffop_loc (input_location,
3730 size_zero_node, BINFO_OFFSET (binfo)));
3733 "offset of empty base %qT may not be ABI-compliant and may"
3734 "change in a future version of GCC",
3735 BINFO_TYPE (binfo));
3738 /* This is an empty base class. We first try to put it at offset
3740 if (layout_conflict_p (binfo,
3741 BINFO_OFFSET (binfo),
3745 /* That didn't work. Now, we move forward from the next
3746 available spot in the class. */
3748 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3751 if (!layout_conflict_p (binfo,
3752 BINFO_OFFSET (binfo),
3755 /* We finally found a spot where there's no overlap. */
3758 /* There's overlap here, too. Bump along to the next spot. */
3759 propagate_binfo_offsets (binfo, alignment);
3763 if (CLASSTYPE_USER_ALIGN (basetype))
3765 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3767 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3768 TYPE_USER_ALIGN (rli->t) = 1;
3774 /* Layout the base given by BINFO in the class indicated by RLI.
3775 *BASE_ALIGN is a running maximum of the alignments of
3776 any base class. OFFSETS gives the location of empty base
3777 subobjects. T is the most derived type. Return nonzero if the new
3778 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3779 *NEXT_FIELD, unless BINFO is for an empty base class.
3781 Returns the location at which the next field should be inserted. */
3784 build_base_field (record_layout_info rli, tree binfo,
3785 splay_tree offsets, tree *next_field)
3788 tree basetype = BINFO_TYPE (binfo);
3790 if (!COMPLETE_TYPE_P (basetype))
3791 /* This error is now reported in xref_tag, thus giving better
3792 location information. */
3795 /* Place the base class. */
3796 if (!is_empty_class (basetype))
3800 /* The containing class is non-empty because it has a non-empty
3802 CLASSTYPE_EMPTY_P (t) = 0;
3804 /* Create the FIELD_DECL. */
3805 decl = build_decl (input_location,
3806 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3807 DECL_ARTIFICIAL (decl) = 1;
3808 DECL_IGNORED_P (decl) = 1;
3809 DECL_FIELD_CONTEXT (decl) = t;
3810 if (CLASSTYPE_AS_BASE (basetype))
3812 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3813 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3814 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3815 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3816 DECL_MODE (decl) = TYPE_MODE (basetype);
3817 DECL_FIELD_IS_BASE (decl) = 1;
3819 /* Try to place the field. It may take more than one try if we
3820 have a hard time placing the field without putting two
3821 objects of the same type at the same address. */
3822 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3823 /* Add the new FIELD_DECL to the list of fields for T. */
3824 DECL_CHAIN (decl) = *next_field;
3826 next_field = &DECL_CHAIN (decl);
3834 /* On some platforms (ARM), even empty classes will not be
3836 eoc = round_up_loc (input_location,
3837 rli_size_unit_so_far (rli),
3838 CLASSTYPE_ALIGN_UNIT (basetype));
3839 atend = layout_empty_base (rli, binfo, eoc, offsets);
3840 /* A nearly-empty class "has no proper base class that is empty,
3841 not morally virtual, and at an offset other than zero." */
3842 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3845 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3846 /* The check above (used in G++ 3.2) is insufficient because
3847 an empty class placed at offset zero might itself have an
3848 empty base at a nonzero offset. */
3849 else if (walk_subobject_offsets (basetype,
3850 empty_base_at_nonzero_offset_p,
3853 /*max_offset=*/NULL_TREE,
3856 if (abi_version_at_least (2))
3857 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3860 "class %qT will be considered nearly empty in a "
3861 "future version of GCC", t);
3865 /* We do not create a FIELD_DECL for empty base classes because
3866 it might overlap some other field. We want to be able to
3867 create CONSTRUCTORs for the class by iterating over the
3868 FIELD_DECLs, and the back end does not handle overlapping
3871 /* An empty virtual base causes a class to be non-empty
3872 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3873 here because that was already done when the virtual table
3874 pointer was created. */
3877 /* Record the offsets of BINFO and its base subobjects. */
3878 record_subobject_offsets (binfo,
3879 BINFO_OFFSET (binfo),
3881 /*is_data_member=*/false);
3886 /* Layout all of the non-virtual base classes. Record empty
3887 subobjects in OFFSETS. T is the most derived type. Return nonzero
3888 if the type cannot be nearly empty. The fields created
3889 corresponding to the base classes will be inserted at
3893 build_base_fields (record_layout_info rli,
3894 splay_tree offsets, tree *next_field)
3896 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3899 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3902 /* The primary base class is always allocated first. */
3903 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3904 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3905 offsets, next_field);
3907 /* Now allocate the rest of the bases. */
3908 for (i = 0; i < n_baseclasses; ++i)
3912 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3914 /* The primary base was already allocated above, so we don't
3915 need to allocate it again here. */
3916 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3919 /* Virtual bases are added at the end (a primary virtual base
3920 will have already been added). */
3921 if (BINFO_VIRTUAL_P (base_binfo))
3924 next_field = build_base_field (rli, base_binfo,
3925 offsets, next_field);
3929 /* Go through the TYPE_METHODS of T issuing any appropriate
3930 diagnostics, figuring out which methods override which other
3931 methods, and so forth. */
3934 check_methods (tree t)
3938 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
3940 check_for_override (x, t);
3941 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3942 error ("initializer specified for non-virtual method %q+D", x);
3943 /* The name of the field is the original field name
3944 Save this in auxiliary field for later overloading. */
3945 if (DECL_VINDEX (x))
3947 TYPE_POLYMORPHIC_P (t) = 1;
3948 if (DECL_PURE_VIRTUAL_P (x))
3949 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3951 /* All user-provided destructors are non-trivial.
3952 Constructors and assignment ops are handled in
3953 grok_special_member_properties. */
3954 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
3955 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3959 /* FN is a constructor or destructor. Clone the declaration to create
3960 a specialized in-charge or not-in-charge version, as indicated by
3964 build_clone (tree fn, tree name)
3969 /* Copy the function. */
3970 clone = copy_decl (fn);
3971 /* Reset the function name. */
3972 DECL_NAME (clone) = name;
3973 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3974 /* Remember where this function came from. */
3975 DECL_ABSTRACT_ORIGIN (clone) = fn;
3976 /* Make it easy to find the CLONE given the FN. */
3977 DECL_CHAIN (clone) = DECL_CHAIN (fn);
3978 DECL_CHAIN (fn) = clone;
3980 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3981 if (TREE_CODE (clone) == TEMPLATE_DECL)
3983 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3984 DECL_TEMPLATE_RESULT (clone) = result;
3985 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3986 DECL_TI_TEMPLATE (result) = clone;
3987 TREE_TYPE (clone) = TREE_TYPE (result);
3991 DECL_CLONED_FUNCTION (clone) = fn;
3992 /* There's no pending inline data for this function. */
3993 DECL_PENDING_INLINE_INFO (clone) = NULL;
3994 DECL_PENDING_INLINE_P (clone) = 0;
3996 /* The base-class destructor is not virtual. */
3997 if (name == base_dtor_identifier)
3999 DECL_VIRTUAL_P (clone) = 0;
4000 if (TREE_CODE (clone) != TEMPLATE_DECL)
4001 DECL_VINDEX (clone) = NULL_TREE;
4004 /* If there was an in-charge parameter, drop it from the function
4006 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4012 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4013 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4014 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
4015 /* Skip the `this' parameter. */
4016 parmtypes = TREE_CHAIN (parmtypes);
4017 /* Skip the in-charge parameter. */
4018 parmtypes = TREE_CHAIN (parmtypes);
4019 /* And the VTT parm, in a complete [cd]tor. */
4020 if (DECL_HAS_VTT_PARM_P (fn)
4021 && ! DECL_NEEDS_VTT_PARM_P (clone))
4022 parmtypes = TREE_CHAIN (parmtypes);
4023 /* If this is subobject constructor or destructor, add the vtt
4026 = build_method_type_directly (basetype,
4027 TREE_TYPE (TREE_TYPE (clone)),
4030 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
4033 = cp_build_type_attribute_variant (TREE_TYPE (clone),
4034 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
4037 /* Copy the function parameters. */
4038 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
4039 /* Remove the in-charge parameter. */
4040 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4042 DECL_CHAIN (DECL_ARGUMENTS (clone))
4043 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4044 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
4046 /* And the VTT parm, in a complete [cd]tor. */
4047 if (DECL_HAS_VTT_PARM_P (fn))
4049 if (DECL_NEEDS_VTT_PARM_P (clone))
4050 DECL_HAS_VTT_PARM_P (clone) = 1;
4053 DECL_CHAIN (DECL_ARGUMENTS (clone))
4054 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4055 DECL_HAS_VTT_PARM_P (clone) = 0;
4059 for (parms = DECL_ARGUMENTS (clone); parms; parms = DECL_CHAIN (parms))
4061 DECL_CONTEXT (parms) = clone;
4062 cxx_dup_lang_specific_decl (parms);
4065 /* Create the RTL for this function. */
4066 SET_DECL_RTL (clone, NULL);
4067 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
4070 note_decl_for_pch (clone);
4075 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4076 not invoke this function directly.
4078 For a non-thunk function, returns the address of the slot for storing
4079 the function it is a clone of. Otherwise returns NULL_TREE.
4081 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4082 cloned_function is unset. This is to support the separate
4083 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4084 on a template makes sense, but not the former. */
4087 decl_cloned_function_p (const_tree decl, bool just_testing)
4091 decl = STRIP_TEMPLATE (decl);
4093 if (TREE_CODE (decl) != FUNCTION_DECL
4094 || !DECL_LANG_SPECIFIC (decl)
4095 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
4097 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4099 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
4105 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
4106 if (just_testing && *ptr == NULL_TREE)
4112 /* Produce declarations for all appropriate clones of FN. If
4113 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4114 CLASTYPE_METHOD_VEC as well. */
4117 clone_function_decl (tree fn, int update_method_vec_p)
4121 /* Avoid inappropriate cloning. */
4123 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (fn)))
4126 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4128 /* For each constructor, we need two variants: an in-charge version
4129 and a not-in-charge version. */
4130 clone = build_clone (fn, complete_ctor_identifier);
4131 if (update_method_vec_p)
4132 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4133 clone = build_clone (fn, base_ctor_identifier);
4134 if (update_method_vec_p)
4135 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4139 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4141 /* For each destructor, we need three variants: an in-charge
4142 version, a not-in-charge version, and an in-charge deleting
4143 version. We clone the deleting version first because that
4144 means it will go second on the TYPE_METHODS list -- and that
4145 corresponds to the correct layout order in the virtual
4148 For a non-virtual destructor, we do not build a deleting
4150 if (DECL_VIRTUAL_P (fn))
4152 clone = build_clone (fn, deleting_dtor_identifier);
4153 if (update_method_vec_p)
4154 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4156 clone = build_clone (fn, complete_dtor_identifier);
4157 if (update_method_vec_p)
4158 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4159 clone = build_clone (fn, base_dtor_identifier);
4160 if (update_method_vec_p)
4161 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4164 /* Note that this is an abstract function that is never emitted. */
4165 DECL_ABSTRACT (fn) = 1;
4168 /* DECL is an in charge constructor, which is being defined. This will
4169 have had an in class declaration, from whence clones were
4170 declared. An out-of-class definition can specify additional default
4171 arguments. As it is the clones that are involved in overload
4172 resolution, we must propagate the information from the DECL to its
4176 adjust_clone_args (tree decl)
4180 for (clone = DECL_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4181 clone = DECL_CHAIN (clone))
4183 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4184 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4185 tree decl_parms, clone_parms;
4187 clone_parms = orig_clone_parms;
4189 /* Skip the 'this' parameter. */
4190 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4191 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4193 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4194 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4195 if (DECL_HAS_VTT_PARM_P (decl))
4196 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4198 clone_parms = orig_clone_parms;
4199 if (DECL_HAS_VTT_PARM_P (clone))
4200 clone_parms = TREE_CHAIN (clone_parms);
4202 for (decl_parms = orig_decl_parms; decl_parms;
4203 decl_parms = TREE_CHAIN (decl_parms),
4204 clone_parms = TREE_CHAIN (clone_parms))
4206 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4207 TREE_TYPE (clone_parms)));
4209 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4211 /* A default parameter has been added. Adjust the
4212 clone's parameters. */
4213 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4214 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4215 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4218 clone_parms = orig_decl_parms;
4220 if (DECL_HAS_VTT_PARM_P (clone))
4222 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4223 TREE_VALUE (orig_clone_parms),
4225 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4227 type = build_method_type_directly (basetype,
4228 TREE_TYPE (TREE_TYPE (clone)),
4231 type = build_exception_variant (type, exceptions);
4233 type = cp_build_type_attribute_variant (type, attrs);
4234 TREE_TYPE (clone) = type;
4236 clone_parms = NULL_TREE;
4240 gcc_assert (!clone_parms);
4244 /* For each of the constructors and destructors in T, create an
4245 in-charge and not-in-charge variant. */
4248 clone_constructors_and_destructors (tree t)
4252 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4254 if (!CLASSTYPE_METHOD_VEC (t))
4257 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4258 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4259 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4260 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4263 /* Returns true iff class T has a user-defined constructor other than
4264 the default constructor. */
4267 type_has_user_nondefault_constructor (tree t)
4271 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4274 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4276 tree fn = OVL_CURRENT (fns);
4277 if (!DECL_ARTIFICIAL (fn)
4278 && (TREE_CODE (fn) == TEMPLATE_DECL
4279 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4287 /* Returns the defaulted constructor if T has one. Otherwise, returns
4291 in_class_defaulted_default_constructor (tree t)
4295 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4298 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4300 tree fn = OVL_CURRENT (fns);
4302 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4304 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4305 while (args && TREE_PURPOSE (args))
4306 args = TREE_CHAIN (args);
4307 if (!args || args == void_list_node)
4315 /* Returns true iff FN is a user-provided function, i.e. user-declared
4316 and not defaulted at its first declaration; or explicit, private,
4317 protected, or non-const. */
4320 user_provided_p (tree fn)
4322 if (TREE_CODE (fn) == TEMPLATE_DECL)
4325 return (!DECL_ARTIFICIAL (fn)
4326 && !DECL_DEFAULTED_IN_CLASS_P (fn));
4329 /* Returns true iff class T has a user-provided constructor. */
4332 type_has_user_provided_constructor (tree t)
4336 if (!CLASS_TYPE_P (t))
4339 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4342 /* This can happen in error cases; avoid crashing. */
4343 if (!CLASSTYPE_METHOD_VEC (t))
4346 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4347 if (user_provided_p (OVL_CURRENT (fns)))
4353 /* Returns true iff class T has a user-provided default constructor. */
4356 type_has_user_provided_default_constructor (tree t)
4360 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4363 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4365 tree fn = OVL_CURRENT (fns);
4366 if (TREE_CODE (fn) == FUNCTION_DECL
4367 && user_provided_p (fn)
4368 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)))
4375 /* Returns true iff for class T, a synthesized default constructor
4376 would be constexpr. */
4379 synthesized_default_constructor_is_constexpr (tree t)
4381 /* A defaulted default constructor is constexpr
4382 if there is nothing to initialize. */
4383 /* FIXME adjust for non-static data member initializers. */
4384 return is_really_empty_class (t);
4387 /* Returns true iff class T has a constexpr default constructor. */
4390 type_has_constexpr_default_constructor (tree t)
4394 if (!CLASS_TYPE_P (t))
4396 /* The caller should have stripped an enclosing array. */
4397 gcc_assert (TREE_CODE (t) != ARRAY_TYPE);
4400 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t))
4401 return synthesized_default_constructor_is_constexpr (t);
4402 fns = locate_ctor (t);
4403 return (fns && DECL_DECLARED_CONSTEXPR_P (fns));
4406 /* Returns true iff class TYPE has a virtual destructor. */
4409 type_has_virtual_destructor (tree type)
4413 if (!CLASS_TYPE_P (type))
4416 gcc_assert (COMPLETE_TYPE_P (type));
4417 dtor = CLASSTYPE_DESTRUCTORS (type);
4418 return (dtor && DECL_VIRTUAL_P (dtor));
4421 /* Returns true iff class T has a move constructor. */
4424 type_has_move_constructor (tree t)
4428 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4430 gcc_assert (COMPLETE_TYPE_P (t));
4431 lazily_declare_fn (sfk_move_constructor, t);
4434 if (!CLASSTYPE_METHOD_VEC (t))
4437 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4438 if (move_fn_p (OVL_CURRENT (fns)))
4444 /* Returns true iff class T has a move assignment operator. */
4447 type_has_move_assign (tree t)
4451 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4453 gcc_assert (COMPLETE_TYPE_P (t));
4454 lazily_declare_fn (sfk_move_assignment, t);
4457 for (fns = lookup_fnfields_slot (t, ansi_assopname (NOP_EXPR));
4458 fns; fns = OVL_NEXT (fns))
4459 if (move_fn_p (OVL_CURRENT (fns)))
4465 /* Nonzero if we need to build up a constructor call when initializing an
4466 object of this class, either because it has a user-provided constructor
4467 or because it doesn't have a default constructor (so we need to give an
4468 error if no initializer is provided). Use TYPE_NEEDS_CONSTRUCTING when
4469 what you care about is whether or not an object can be produced by a
4470 constructor (e.g. so we don't set TREE_READONLY on const variables of
4471 such type); use this function when what you care about is whether or not
4472 to try to call a constructor to create an object. The latter case is
4473 the former plus some cases of constructors that cannot be called. */
4476 type_build_ctor_call (tree t)
4479 if (TYPE_NEEDS_CONSTRUCTING (t))
4481 inner = strip_array_types (t);
4482 return (CLASS_TYPE_P (inner) && !TYPE_HAS_DEFAULT_CONSTRUCTOR (inner)
4483 && !ANON_AGGR_TYPE_P (inner));
4486 /* Remove all zero-width bit-fields from T. */
4489 remove_zero_width_bit_fields (tree t)
4493 fieldsp = &TYPE_FIELDS (t);
4496 if (TREE_CODE (*fieldsp) == FIELD_DECL
4497 && DECL_C_BIT_FIELD (*fieldsp)
4498 /* We should not be confused by the fact that grokbitfield
4499 temporarily sets the width of the bit field into
4500 DECL_INITIAL (*fieldsp).
4501 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4503 && integer_zerop (DECL_SIZE (*fieldsp)))
4504 *fieldsp = DECL_CHAIN (*fieldsp);
4506 fieldsp = &DECL_CHAIN (*fieldsp);
4510 /* Returns TRUE iff we need a cookie when dynamically allocating an
4511 array whose elements have the indicated class TYPE. */
4514 type_requires_array_cookie (tree type)
4517 bool has_two_argument_delete_p = false;
4519 gcc_assert (CLASS_TYPE_P (type));
4521 /* If there's a non-trivial destructor, we need a cookie. In order
4522 to iterate through the array calling the destructor for each
4523 element, we'll have to know how many elements there are. */
4524 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4527 /* If the usual deallocation function is a two-argument whose second
4528 argument is of type `size_t', then we have to pass the size of
4529 the array to the deallocation function, so we will need to store
4531 fns = lookup_fnfields (TYPE_BINFO (type),
4532 ansi_opname (VEC_DELETE_EXPR),
4534 /* If there are no `operator []' members, or the lookup is
4535 ambiguous, then we don't need a cookie. */
4536 if (!fns || fns == error_mark_node)
4538 /* Loop through all of the functions. */
4539 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4544 /* Select the current function. */
4545 fn = OVL_CURRENT (fns);
4546 /* See if this function is a one-argument delete function. If
4547 it is, then it will be the usual deallocation function. */
4548 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4549 if (second_parm == void_list_node)
4551 /* Do not consider this function if its second argument is an
4555 /* Otherwise, if we have a two-argument function and the second
4556 argument is `size_t', it will be the usual deallocation
4557 function -- unless there is one-argument function, too. */
4558 if (TREE_CHAIN (second_parm) == void_list_node
4559 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4560 has_two_argument_delete_p = true;
4563 return has_two_argument_delete_p;
4566 /* Finish computing the `literal type' property of class type T.
4568 At this point, we have already processed base classes and
4569 non-static data members. We need to check whether the copy
4570 constructor is trivial, the destructor is trivial, and there
4571 is a trivial default constructor or at least one constexpr
4572 constructor other than the copy constructor. */
4575 finalize_literal_type_property (tree t)
4579 if (cxx_dialect < cxx0x
4580 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
4581 /* FIXME These constraints seem unnecessary; remove from standard.
4582 || !TYPE_HAS_TRIVIAL_COPY_CTOR (t)
4583 || TYPE_HAS_COMPLEX_MOVE_CTOR (t)*/ )
4584 CLASSTYPE_LITERAL_P (t) = false;
4585 else if (CLASSTYPE_LITERAL_P (t) && !TYPE_HAS_TRIVIAL_DFLT (t)
4586 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4587 CLASSTYPE_LITERAL_P (t) = false;
4589 if (!CLASSTYPE_LITERAL_P (t))
4590 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4591 if (DECL_DECLARED_CONSTEXPR_P (fn)
4592 && TREE_CODE (fn) != TEMPLATE_DECL
4593 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
4594 && !DECL_CONSTRUCTOR_P (fn))
4596 DECL_DECLARED_CONSTEXPR_P (fn) = false;
4597 if (!DECL_TEMPLATE_INFO (fn))
4598 error ("enclosing class of %q+#D is not a literal type", fn);
4602 /* Check the validity of the bases and members declared in T. Add any
4603 implicitly-generated functions (like copy-constructors and
4604 assignment operators). Compute various flag bits (like
4605 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4606 level: i.e., independently of the ABI in use. */
4609 check_bases_and_members (tree t)
4611 /* Nonzero if the implicitly generated copy constructor should take
4612 a non-const reference argument. */
4613 int cant_have_const_ctor;
4614 /* Nonzero if the implicitly generated assignment operator
4615 should take a non-const reference argument. */
4616 int no_const_asn_ref;
4618 bool saved_complex_asn_ref;
4619 bool saved_nontrivial_dtor;
4622 /* By default, we use const reference arguments and generate default
4624 cant_have_const_ctor = 0;
4625 no_const_asn_ref = 0;
4627 /* Check all the base-classes. */
4628 check_bases (t, &cant_have_const_ctor,
4631 /* Check all the method declarations. */
4634 /* Save the initial values of these flags which only indicate whether
4635 or not the class has user-provided functions. As we analyze the
4636 bases and members we can set these flags for other reasons. */
4637 saved_complex_asn_ref = TYPE_HAS_COMPLEX_COPY_ASSIGN (t);
4638 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4640 /* Check all the data member declarations. We cannot call
4641 check_field_decls until we have called check_bases check_methods,
4642 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4643 being set appropriately. */
4644 check_field_decls (t, &access_decls,
4645 &cant_have_const_ctor,
4648 /* A nearly-empty class has to be vptr-containing; a nearly empty
4649 class contains just a vptr. */
4650 if (!TYPE_CONTAINS_VPTR_P (t))
4651 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4653 /* Do some bookkeeping that will guide the generation of implicitly
4654 declared member functions. */
4655 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4656 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4657 /* We need to call a constructor for this class if it has a
4658 user-provided constructor, or if the default constructor is going
4659 to initialize the vptr. (This is not an if-and-only-if;
4660 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4661 themselves need constructing.) */
4662 TYPE_NEEDS_CONSTRUCTING (t)
4663 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4666 An aggregate is an array or a class with no user-provided
4667 constructors ... and no virtual functions.
4669 Again, other conditions for being an aggregate are checked
4671 CLASSTYPE_NON_AGGREGATE (t)
4672 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4673 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4674 retain the old definition internally for ABI reasons. */
4675 CLASSTYPE_NON_LAYOUT_POD_P (t)
4676 |= (CLASSTYPE_NON_AGGREGATE (t)
4677 || saved_nontrivial_dtor || saved_complex_asn_ref);
4678 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
4679 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4680 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4681 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4683 /* If the class has no user-declared constructor, but does have
4684 non-static const or reference data members that can never be
4685 initialized, issue a warning. */
4686 if (warn_uninitialized
4687 /* Classes with user-declared constructors are presumed to
4688 initialize these members. */
4689 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4690 /* Aggregates can be initialized with brace-enclosed
4692 && CLASSTYPE_NON_AGGREGATE (t))
4696 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
4700 if (TREE_CODE (field) != FIELD_DECL)
4703 type = TREE_TYPE (field);
4704 if (TREE_CODE (type) == REFERENCE_TYPE)
4705 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4706 "in class without a constructor", field);
4707 else if (CP_TYPE_CONST_P (type)
4708 && (!CLASS_TYPE_P (type)
4709 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4710 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4711 "in class without a constructor", field);
4715 /* Synthesize any needed methods. */
4716 add_implicitly_declared_members (t,
4717 cant_have_const_ctor,
4720 /* Check defaulted declarations here so we have cant_have_const_ctor
4721 and don't need to worry about clones. */
4722 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4723 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4725 int copy = copy_fn_p (fn);
4729 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
4730 : !no_const_asn_ref);
4731 bool fn_const_p = (copy == 2);
4733 if (fn_const_p && !imp_const_p)
4734 /* If the function is defaulted outside the class, we just
4735 give the synthesis error. */
4736 error ("%q+D declared to take const reference, but implicit "
4737 "declaration would take non-const", fn);
4738 else if (imp_const_p && !fn_const_p)
4739 error ("%q+D declared to take non-const reference cannot be "
4740 "defaulted in the class body", fn);
4742 defaulted_late_check (fn);
4745 if (LAMBDA_TYPE_P (t))
4747 /* "The closure type associated with a lambda-expression has a deleted
4748 default constructor and a deleted copy assignment operator." */
4749 TYPE_NEEDS_CONSTRUCTING (t) = 1;
4750 TYPE_HAS_COMPLEX_DFLT (t) = 1;
4751 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
4752 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 0;
4754 /* "This class type is not an aggregate." */
4755 CLASSTYPE_NON_AGGREGATE (t) = 1;
4758 /* Compute the 'literal type' property before we
4759 do anything with non-static member functions. */
4760 finalize_literal_type_property (t);
4762 /* Create the in-charge and not-in-charge variants of constructors
4764 clone_constructors_and_destructors (t);
4766 /* Process the using-declarations. */
4767 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4768 handle_using_decl (TREE_VALUE (access_decls), t);
4770 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4771 finish_struct_methods (t);
4773 /* Figure out whether or not we will need a cookie when dynamically
4774 allocating an array of this type. */
4775 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4776 = type_requires_array_cookie (t);
4779 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4780 accordingly. If a new vfield was created (because T doesn't have a
4781 primary base class), then the newly created field is returned. It
4782 is not added to the TYPE_FIELDS list; it is the caller's
4783 responsibility to do that. Accumulate declared virtual functions
4787 create_vtable_ptr (tree t, tree* virtuals_p)
4791 /* Collect the virtual functions declared in T. */
4792 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4793 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4794 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4796 tree new_virtual = make_node (TREE_LIST);
4798 BV_FN (new_virtual) = fn;
4799 BV_DELTA (new_virtual) = integer_zero_node;
4800 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4802 TREE_CHAIN (new_virtual) = *virtuals_p;
4803 *virtuals_p = new_virtual;
4806 /* If we couldn't find an appropriate base class, create a new field
4807 here. Even if there weren't any new virtual functions, we might need a
4808 new virtual function table if we're supposed to include vptrs in
4809 all classes that need them. */
4810 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4812 /* We build this decl with vtbl_ptr_type_node, which is a
4813 `vtable_entry_type*'. It might seem more precise to use
4814 `vtable_entry_type (*)[N]' where N is the number of virtual
4815 functions. However, that would require the vtable pointer in
4816 base classes to have a different type than the vtable pointer
4817 in derived classes. We could make that happen, but that
4818 still wouldn't solve all the problems. In particular, the
4819 type-based alias analysis code would decide that assignments
4820 to the base class vtable pointer can't alias assignments to
4821 the derived class vtable pointer, since they have different
4822 types. Thus, in a derived class destructor, where the base
4823 class constructor was inlined, we could generate bad code for
4824 setting up the vtable pointer.
4826 Therefore, we use one type for all vtable pointers. We still
4827 use a type-correct type; it's just doesn't indicate the array
4828 bounds. That's better than using `void*' or some such; it's
4829 cleaner, and it let's the alias analysis code know that these
4830 stores cannot alias stores to void*! */
4833 field = build_decl (input_location,
4834 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4835 DECL_VIRTUAL_P (field) = 1;
4836 DECL_ARTIFICIAL (field) = 1;
4837 DECL_FIELD_CONTEXT (field) = t;
4838 DECL_FCONTEXT (field) = t;
4839 if (TYPE_PACKED (t))
4840 DECL_PACKED (field) = 1;
4842 TYPE_VFIELD (t) = field;
4844 /* This class is non-empty. */
4845 CLASSTYPE_EMPTY_P (t) = 0;
4853 /* Add OFFSET to all base types of BINFO which is a base in the
4854 hierarchy dominated by T.
4856 OFFSET, which is a type offset, is number of bytes. */
4859 propagate_binfo_offsets (tree binfo, tree offset)
4865 /* Update BINFO's offset. */
4866 BINFO_OFFSET (binfo)
4867 = convert (sizetype,
4868 size_binop (PLUS_EXPR,
4869 convert (ssizetype, BINFO_OFFSET (binfo)),
4872 /* Find the primary base class. */
4873 primary_binfo = get_primary_binfo (binfo);
4875 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4876 propagate_binfo_offsets (primary_binfo, offset);
4878 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4880 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4882 /* Don't do the primary base twice. */
4883 if (base_binfo == primary_binfo)
4886 if (BINFO_VIRTUAL_P (base_binfo))
4889 propagate_binfo_offsets (base_binfo, offset);
4893 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4894 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4895 empty subobjects of T. */
4898 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4902 bool first_vbase = true;
4905 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4908 if (!abi_version_at_least(2))
4910 /* In G++ 3.2, we incorrectly rounded the size before laying out
4911 the virtual bases. */
4912 finish_record_layout (rli, /*free_p=*/false);
4913 #ifdef STRUCTURE_SIZE_BOUNDARY
4914 /* Packed structures don't need to have minimum size. */
4915 if (! TYPE_PACKED (t))
4916 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4918 rli->offset = TYPE_SIZE_UNIT (t);
4919 rli->bitpos = bitsize_zero_node;
4920 rli->record_align = TYPE_ALIGN (t);
4923 /* Find the last field. The artificial fields created for virtual
4924 bases will go after the last extant field to date. */
4925 next_field = &TYPE_FIELDS (t);
4927 next_field = &DECL_CHAIN (*next_field);
4929 /* Go through the virtual bases, allocating space for each virtual
4930 base that is not already a primary base class. These are
4931 allocated in inheritance graph order. */
4932 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4934 if (!BINFO_VIRTUAL_P (vbase))
4937 if (!BINFO_PRIMARY_P (vbase))
4939 tree basetype = TREE_TYPE (vbase);
4941 /* This virtual base is not a primary base of any class in the
4942 hierarchy, so we have to add space for it. */
4943 next_field = build_base_field (rli, vbase,
4944 offsets, next_field);
4946 /* If the first virtual base might have been placed at a
4947 lower address, had we started from CLASSTYPE_SIZE, rather
4948 than TYPE_SIZE, issue a warning. There can be both false
4949 positives and false negatives from this warning in rare
4950 cases; to deal with all the possibilities would probably
4951 require performing both layout algorithms and comparing
4952 the results which is not particularly tractable. */
4956 (size_binop (CEIL_DIV_EXPR,
4957 round_up_loc (input_location,
4959 CLASSTYPE_ALIGN (basetype)),
4961 BINFO_OFFSET (vbase))))
4963 "offset of virtual base %qT is not ABI-compliant and "
4964 "may change in a future version of GCC",
4967 first_vbase = false;
4972 /* Returns the offset of the byte just past the end of the base class
4976 end_of_base (tree binfo)
4980 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
4981 size = TYPE_SIZE_UNIT (char_type_node);
4982 else if (is_empty_class (BINFO_TYPE (binfo)))
4983 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4984 allocate some space for it. It cannot have virtual bases, so
4985 TYPE_SIZE_UNIT is fine. */
4986 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4988 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4990 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4993 /* Returns the offset of the byte just past the end of the base class
4994 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4995 only non-virtual bases are included. */
4998 end_of_class (tree t, int include_virtuals_p)
5000 tree result = size_zero_node;
5001 VEC(tree,gc) *vbases;
5007 for (binfo = TYPE_BINFO (t), i = 0;
5008 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5010 if (!include_virtuals_p
5011 && BINFO_VIRTUAL_P (base_binfo)
5012 && (!BINFO_PRIMARY_P (base_binfo)
5013 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
5016 offset = end_of_base (base_binfo);
5017 if (INT_CST_LT_UNSIGNED (result, offset))
5021 /* G++ 3.2 did not check indirect virtual bases. */
5022 if (abi_version_at_least (2) && include_virtuals_p)
5023 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5024 VEC_iterate (tree, vbases, i, base_binfo); i++)
5026 offset = end_of_base (base_binfo);
5027 if (INT_CST_LT_UNSIGNED (result, offset))
5034 /* Warn about bases of T that are inaccessible because they are
5035 ambiguous. For example:
5038 struct T : public S {};
5039 struct U : public S, public T {};
5041 Here, `(S*) new U' is not allowed because there are two `S'
5045 warn_about_ambiguous_bases (tree t)
5048 VEC(tree,gc) *vbases;
5053 /* If there are no repeated bases, nothing can be ambiguous. */
5054 if (!CLASSTYPE_REPEATED_BASE_P (t))
5057 /* Check direct bases. */
5058 for (binfo = TYPE_BINFO (t), i = 0;
5059 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5061 basetype = BINFO_TYPE (base_binfo);
5063 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5064 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
5068 /* Check for ambiguous virtual bases. */
5070 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5071 VEC_iterate (tree, vbases, i, binfo); i++)
5073 basetype = BINFO_TYPE (binfo);
5075 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5076 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
5081 /* Compare two INTEGER_CSTs K1 and K2. */
5084 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
5086 return tree_int_cst_compare ((tree) k1, (tree) k2);
5089 /* Increase the size indicated in RLI to account for empty classes
5090 that are "off the end" of the class. */
5093 include_empty_classes (record_layout_info rli)
5098 /* It might be the case that we grew the class to allocate a
5099 zero-sized base class. That won't be reflected in RLI, yet,
5100 because we are willing to overlay multiple bases at the same
5101 offset. However, now we need to make sure that RLI is big enough
5102 to reflect the entire class. */
5103 eoc = end_of_class (rli->t,
5104 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
5105 rli_size = rli_size_unit_so_far (rli);
5106 if (TREE_CODE (rli_size) == INTEGER_CST
5107 && INT_CST_LT_UNSIGNED (rli_size, eoc))
5109 if (!abi_version_at_least (2))
5110 /* In version 1 of the ABI, the size of a class that ends with
5111 a bitfield was not rounded up to a whole multiple of a
5112 byte. Because rli_size_unit_so_far returns only the number
5113 of fully allocated bytes, any extra bits were not included
5115 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
5117 /* The size should have been rounded to a whole byte. */
5118 gcc_assert (tree_int_cst_equal
5119 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
5121 = size_binop (PLUS_EXPR,
5123 size_binop (MULT_EXPR,
5124 convert (bitsizetype,
5125 size_binop (MINUS_EXPR,
5127 bitsize_int (BITS_PER_UNIT)));
5128 normalize_rli (rli);
5132 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
5133 BINFO_OFFSETs for all of the base-classes. Position the vtable
5134 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
5137 layout_class_type (tree t, tree *virtuals_p)
5139 tree non_static_data_members;
5142 record_layout_info rli;
5143 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
5144 types that appear at that offset. */
5145 splay_tree empty_base_offsets;
5146 /* True if the last field layed out was a bit-field. */
5147 bool last_field_was_bitfield = false;
5148 /* The location at which the next field should be inserted. */
5150 /* T, as a base class. */
5153 /* Keep track of the first non-static data member. */
5154 non_static_data_members = TYPE_FIELDS (t);
5156 /* Start laying out the record. */
5157 rli = start_record_layout (t);
5159 /* Mark all the primary bases in the hierarchy. */
5160 determine_primary_bases (t);
5162 /* Create a pointer to our virtual function table. */
5163 vptr = create_vtable_ptr (t, virtuals_p);
5165 /* The vptr is always the first thing in the class. */
5168 DECL_CHAIN (vptr) = TYPE_FIELDS (t);
5169 TYPE_FIELDS (t) = vptr;
5170 next_field = &DECL_CHAIN (vptr);
5171 place_field (rli, vptr);
5174 next_field = &TYPE_FIELDS (t);
5176 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5177 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
5179 build_base_fields (rli, empty_base_offsets, next_field);
5181 /* Layout the non-static data members. */
5182 for (field = non_static_data_members; field; field = DECL_CHAIN (field))
5187 /* We still pass things that aren't non-static data members to
5188 the back end, in case it wants to do something with them. */
5189 if (TREE_CODE (field) != FIELD_DECL)
5191 place_field (rli, field);
5192 /* If the static data member has incomplete type, keep track
5193 of it so that it can be completed later. (The handling
5194 of pending statics in finish_record_layout is
5195 insufficient; consider:
5198 struct S2 { static S1 s1; };
5200 At this point, finish_record_layout will be called, but
5201 S1 is still incomplete.) */
5202 if (TREE_CODE (field) == VAR_DECL)
5204 maybe_register_incomplete_var (field);
5205 /* The visibility of static data members is determined
5206 at their point of declaration, not their point of
5208 determine_visibility (field);
5213 type = TREE_TYPE (field);
5214 if (type == error_mark_node)
5217 padding = NULL_TREE;
5219 /* If this field is a bit-field whose width is greater than its
5220 type, then there are some special rules for allocating
5222 if (DECL_C_BIT_FIELD (field)
5223 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
5227 bool was_unnamed_p = false;
5228 /* We must allocate the bits as if suitably aligned for the
5229 longest integer type that fits in this many bits. type
5230 of the field. Then, we are supposed to use the left over
5231 bits as additional padding. */
5232 for (itk = itk_char; itk != itk_none; ++itk)
5233 if (integer_types[itk] != NULL_TREE
5234 && (INT_CST_LT (size_int (MAX_FIXED_MODE_SIZE),
5235 TYPE_SIZE (integer_types[itk]))
5236 || INT_CST_LT (DECL_SIZE (field),
5237 TYPE_SIZE (integer_types[itk]))))
5240 /* ITK now indicates a type that is too large for the
5241 field. We have to back up by one to find the largest
5246 integer_type = integer_types[itk];
5247 } while (itk > 0 && integer_type == NULL_TREE);
5249 /* Figure out how much additional padding is required. GCC
5250 3.2 always created a padding field, even if it had zero
5252 if (!abi_version_at_least (2)
5253 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
5255 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
5256 /* In a union, the padding field must have the full width
5257 of the bit-field; all fields start at offset zero. */
5258 padding = DECL_SIZE (field);
5261 if (TREE_CODE (t) == UNION_TYPE)
5262 warning (OPT_Wabi, "size assigned to %qT may not be "
5263 "ABI-compliant and may change in a future "
5266 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
5267 TYPE_SIZE (integer_type));
5270 #ifdef PCC_BITFIELD_TYPE_MATTERS
5271 /* An unnamed bitfield does not normally affect the
5272 alignment of the containing class on a target where
5273 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5274 make any exceptions for unnamed bitfields when the
5275 bitfields are longer than their types. Therefore, we
5276 temporarily give the field a name. */
5277 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
5279 was_unnamed_p = true;
5280 DECL_NAME (field) = make_anon_name ();
5283 DECL_SIZE (field) = TYPE_SIZE (integer_type);
5284 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
5285 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
5286 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5287 empty_base_offsets);
5289 DECL_NAME (field) = NULL_TREE;
5290 /* Now that layout has been performed, set the size of the
5291 field to the size of its declared type; the rest of the
5292 field is effectively invisible. */
5293 DECL_SIZE (field) = TYPE_SIZE (type);
5294 /* We must also reset the DECL_MODE of the field. */
5295 if (abi_version_at_least (2))
5296 DECL_MODE (field) = TYPE_MODE (type);
5298 && DECL_MODE (field) != TYPE_MODE (type))
5299 /* Versions of G++ before G++ 3.4 did not reset the
5302 "the offset of %qD may not be ABI-compliant and may "
5303 "change in a future version of GCC", field);
5306 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5307 empty_base_offsets);
5309 /* Remember the location of any empty classes in FIELD. */
5310 if (abi_version_at_least (2))
5311 record_subobject_offsets (TREE_TYPE (field),
5312 byte_position(field),
5314 /*is_data_member=*/true);
5316 /* If a bit-field does not immediately follow another bit-field,
5317 and yet it starts in the middle of a byte, we have failed to
5318 comply with the ABI. */
5320 && DECL_C_BIT_FIELD (field)
5321 /* The TREE_NO_WARNING flag gets set by Objective-C when
5322 laying out an Objective-C class. The ObjC ABI differs
5323 from the C++ ABI, and so we do not want a warning
5325 && !TREE_NO_WARNING (field)
5326 && !last_field_was_bitfield
5327 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5328 DECL_FIELD_BIT_OFFSET (field),
5329 bitsize_unit_node)))
5330 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5331 "change in a future version of GCC", field);
5333 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5334 offset of the field. */
5336 && !abi_version_at_least (2)
5337 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5338 byte_position (field))
5339 && contains_empty_class_p (TREE_TYPE (field)))
5340 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5341 "classes to be placed at different locations in a "
5342 "future version of GCC", field);
5344 /* The middle end uses the type of expressions to determine the
5345 possible range of expression values. In order to optimize
5346 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5347 must be made aware of the width of "i", via its type.
5349 Because C++ does not have integer types of arbitrary width,
5350 we must (for the purposes of the front end) convert from the
5351 type assigned here to the declared type of the bitfield
5352 whenever a bitfield expression is used as an rvalue.
5353 Similarly, when assigning a value to a bitfield, the value
5354 must be converted to the type given the bitfield here. */
5355 if (DECL_C_BIT_FIELD (field))
5357 unsigned HOST_WIDE_INT width;
5358 tree ftype = TREE_TYPE (field);
5359 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5360 if (width != TYPE_PRECISION (ftype))
5363 = c_build_bitfield_integer_type (width,
5364 TYPE_UNSIGNED (ftype));
5366 = cp_build_qualified_type (TREE_TYPE (field),
5367 cp_type_quals (ftype));
5371 /* If we needed additional padding after this field, add it
5377 padding_field = build_decl (input_location,
5381 DECL_BIT_FIELD (padding_field) = 1;
5382 DECL_SIZE (padding_field) = padding;
5383 DECL_CONTEXT (padding_field) = t;
5384 DECL_ARTIFICIAL (padding_field) = 1;
5385 DECL_IGNORED_P (padding_field) = 1;
5386 layout_nonempty_base_or_field (rli, padding_field,
5388 empty_base_offsets);
5391 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5394 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5396 /* Make sure that we are on a byte boundary so that the size of
5397 the class without virtual bases will always be a round number
5399 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5400 normalize_rli (rli);
5403 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5405 if (!abi_version_at_least (2))
5406 include_empty_classes(rli);
5408 /* Delete all zero-width bit-fields from the list of fields. Now
5409 that the type is laid out they are no longer important. */
5410 remove_zero_width_bit_fields (t);
5412 /* Create the version of T used for virtual bases. We do not use
5413 make_class_type for this version; this is an artificial type. For
5414 a POD type, we just reuse T. */
5415 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5417 base_t = make_node (TREE_CODE (t));
5419 /* Set the size and alignment for the new type. In G++ 3.2, all
5420 empty classes were considered to have size zero when used as
5422 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5424 TYPE_SIZE (base_t) = bitsize_zero_node;
5425 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5426 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5428 "layout of classes derived from empty class %qT "
5429 "may change in a future version of GCC",
5436 /* If the ABI version is not at least two, and the last
5437 field was a bit-field, RLI may not be on a byte
5438 boundary. In particular, rli_size_unit_so_far might
5439 indicate the last complete byte, while rli_size_so_far
5440 indicates the total number of bits used. Therefore,
5441 rli_size_so_far, rather than rli_size_unit_so_far, is
5442 used to compute TYPE_SIZE_UNIT. */
5443 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5444 TYPE_SIZE_UNIT (base_t)
5445 = size_binop (MAX_EXPR,
5447 size_binop (CEIL_DIV_EXPR,
5448 rli_size_so_far (rli),
5449 bitsize_int (BITS_PER_UNIT))),
5452 = size_binop (MAX_EXPR,
5453 rli_size_so_far (rli),
5454 size_binop (MULT_EXPR,
5455 convert (bitsizetype, eoc),
5456 bitsize_int (BITS_PER_UNIT)));
5458 TYPE_ALIGN (base_t) = rli->record_align;
5459 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5461 /* Copy the fields from T. */
5462 next_field = &TYPE_FIELDS (base_t);
5463 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5464 if (TREE_CODE (field) == FIELD_DECL)
5466 *next_field = build_decl (input_location,
5470 DECL_CONTEXT (*next_field) = base_t;
5471 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5472 DECL_FIELD_BIT_OFFSET (*next_field)
5473 = DECL_FIELD_BIT_OFFSET (field);
5474 DECL_SIZE (*next_field) = DECL_SIZE (field);
5475 DECL_MODE (*next_field) = DECL_MODE (field);
5476 next_field = &DECL_CHAIN (*next_field);
5479 /* Record the base version of the type. */
5480 CLASSTYPE_AS_BASE (t) = base_t;
5481 TYPE_CONTEXT (base_t) = t;
5484 CLASSTYPE_AS_BASE (t) = t;
5486 /* Every empty class contains an empty class. */
5487 if (CLASSTYPE_EMPTY_P (t))
5488 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5490 /* Set the TYPE_DECL for this type to contain the right
5491 value for DECL_OFFSET, so that we can use it as part
5492 of a COMPONENT_REF for multiple inheritance. */
5493 layout_decl (TYPE_MAIN_DECL (t), 0);
5495 /* Now fix up any virtual base class types that we left lying
5496 around. We must get these done before we try to lay out the
5497 virtual function table. As a side-effect, this will remove the
5498 base subobject fields. */
5499 layout_virtual_bases (rli, empty_base_offsets);
5501 /* Make sure that empty classes are reflected in RLI at this
5503 include_empty_classes(rli);
5505 /* Make sure not to create any structures with zero size. */
5506 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5508 build_decl (input_location,
5509 FIELD_DECL, NULL_TREE, char_type_node));
5511 /* If this is a non-POD, declaring it packed makes a difference to how it
5512 can be used as a field; don't let finalize_record_size undo it. */
5513 if (TYPE_PACKED (t) && !layout_pod_type_p (t))
5514 rli->packed_maybe_necessary = true;
5516 /* Let the back end lay out the type. */
5517 finish_record_layout (rli, /*free_p=*/true);
5519 /* Warn about bases that can't be talked about due to ambiguity. */
5520 warn_about_ambiguous_bases (t);
5522 /* Now that we're done with layout, give the base fields the real types. */
5523 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5524 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5525 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5528 splay_tree_delete (empty_base_offsets);
5530 if (CLASSTYPE_EMPTY_P (t)
5531 && tree_int_cst_lt (sizeof_biggest_empty_class,
5532 TYPE_SIZE_UNIT (t)))
5533 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5536 /* Determine the "key method" for the class type indicated by TYPE,
5537 and set CLASSTYPE_KEY_METHOD accordingly. */
5540 determine_key_method (tree type)
5544 if (TYPE_FOR_JAVA (type)
5545 || processing_template_decl
5546 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5547 || CLASSTYPE_INTERFACE_KNOWN (type))
5550 /* The key method is the first non-pure virtual function that is not
5551 inline at the point of class definition. On some targets the
5552 key function may not be inline; those targets should not call
5553 this function until the end of the translation unit. */
5554 for (method = TYPE_METHODS (type); method != NULL_TREE;
5555 method = DECL_CHAIN (method))
5556 if (DECL_VINDEX (method) != NULL_TREE
5557 && ! DECL_DECLARED_INLINE_P (method)
5558 && ! DECL_PURE_VIRTUAL_P (method))
5560 CLASSTYPE_KEY_METHOD (type) = method;
5567 /* Perform processing required when the definition of T (a class type)
5571 finish_struct_1 (tree t)
5574 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5575 tree virtuals = NULL_TREE;
5578 if (COMPLETE_TYPE_P (t))
5580 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5581 error ("redefinition of %q#T", t);
5586 /* If this type was previously laid out as a forward reference,
5587 make sure we lay it out again. */
5588 TYPE_SIZE (t) = NULL_TREE;
5589 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5591 /* Make assumptions about the class; we'll reset the flags if
5593 CLASSTYPE_EMPTY_P (t) = 1;
5594 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5595 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5596 CLASSTYPE_LITERAL_P (t) = true;
5598 /* Do end-of-class semantic processing: checking the validity of the
5599 bases and members and add implicitly generated methods. */
5600 check_bases_and_members (t);
5602 /* Find the key method. */
5603 if (TYPE_CONTAINS_VPTR_P (t))
5605 /* The Itanium C++ ABI permits the key method to be chosen when
5606 the class is defined -- even though the key method so
5607 selected may later turn out to be an inline function. On
5608 some systems (such as ARM Symbian OS) the key method cannot
5609 be determined until the end of the translation unit. On such
5610 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5611 will cause the class to be added to KEYED_CLASSES. Then, in
5612 finish_file we will determine the key method. */
5613 if (targetm.cxx.key_method_may_be_inline ())
5614 determine_key_method (t);
5616 /* If a polymorphic class has no key method, we may emit the vtable
5617 in every translation unit where the class definition appears. */
5618 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5619 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5622 /* Layout the class itself. */
5623 layout_class_type (t, &virtuals);
5624 if (CLASSTYPE_AS_BASE (t) != t)
5625 /* We use the base type for trivial assignments, and hence it
5627 compute_record_mode (CLASSTYPE_AS_BASE (t));
5629 virtuals = modify_all_vtables (t, nreverse (virtuals));
5631 /* If necessary, create the primary vtable for this class. */
5632 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5634 /* We must enter these virtuals into the table. */
5635 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5636 build_primary_vtable (NULL_TREE, t);
5637 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5638 /* Here we know enough to change the type of our virtual
5639 function table, but we will wait until later this function. */
5640 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5643 if (TYPE_CONTAINS_VPTR_P (t))
5648 if (BINFO_VTABLE (TYPE_BINFO (t)))
5649 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5650 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5651 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5653 /* Add entries for virtual functions introduced by this class. */
5654 BINFO_VIRTUALS (TYPE_BINFO (t))
5655 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5657 /* Set DECL_VINDEX for all functions declared in this class. */
5658 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5660 fn = TREE_CHAIN (fn),
5661 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5662 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5664 tree fndecl = BV_FN (fn);
5666 if (DECL_THUNK_P (fndecl))
5667 /* A thunk. We should never be calling this entry directly
5668 from this vtable -- we'd use the entry for the non
5669 thunk base function. */
5670 DECL_VINDEX (fndecl) = NULL_TREE;
5671 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5672 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5676 finish_struct_bits (t);
5678 /* Complete the rtl for any static member objects of the type we're
5680 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
5681 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5682 && TREE_TYPE (x) != error_mark_node
5683 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5684 DECL_MODE (x) = TYPE_MODE (t);
5686 /* Done with FIELDS...now decide whether to sort these for
5687 faster lookups later.
5689 We use a small number because most searches fail (succeeding
5690 ultimately as the search bores through the inheritance
5691 hierarchy), and we want this failure to occur quickly. */
5693 n_fields = count_fields (TYPE_FIELDS (t));
5696 struct sorted_fields_type *field_vec = ggc_alloc_sorted_fields_type
5697 (sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5698 field_vec->len = n_fields;
5699 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5700 qsort (field_vec->elts, n_fields, sizeof (tree),
5702 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
5705 /* Complain if one of the field types requires lower visibility. */
5706 constrain_class_visibility (t);
5708 /* Make the rtl for any new vtables we have created, and unmark
5709 the base types we marked. */
5712 /* Build the VTT for T. */
5715 /* This warning does not make sense for Java classes, since they
5716 cannot have destructors. */
5717 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5721 dtor = CLASSTYPE_DESTRUCTORS (t);
5722 if (/* An implicitly declared destructor is always public. And,
5723 if it were virtual, we would have created it by now. */
5725 || (!DECL_VINDEX (dtor)
5726 && (/* public non-virtual */
5727 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5728 || (/* non-public non-virtual with friends */
5729 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5730 && (CLASSTYPE_FRIEND_CLASSES (t)
5731 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5732 warning (OPT_Wnon_virtual_dtor,
5733 "%q#T has virtual functions and accessible"
5734 " non-virtual destructor", t);
5739 if (warn_overloaded_virtual)
5742 /* Class layout, assignment of virtual table slots, etc., is now
5743 complete. Give the back end a chance to tweak the visibility of
5744 the class or perform any other required target modifications. */
5745 targetm.cxx.adjust_class_at_definition (t);
5747 maybe_suppress_debug_info (t);
5749 dump_class_hierarchy (t);
5751 /* Finish debugging output for this type. */
5752 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5755 /* When T was built up, the member declarations were added in reverse
5756 order. Rearrange them to declaration order. */
5759 unreverse_member_declarations (tree t)
5765 /* The following lists are all in reverse order. Put them in
5766 declaration order now. */
5767 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5768 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5770 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5771 reverse order, so we can't just use nreverse. */
5773 for (x = TYPE_FIELDS (t);
5774 x && TREE_CODE (x) != TYPE_DECL;
5777 next = DECL_CHAIN (x);
5778 DECL_CHAIN (x) = prev;
5783 DECL_CHAIN (TYPE_FIELDS (t)) = x;
5785 TYPE_FIELDS (t) = prev;
5790 finish_struct (tree t, tree attributes)
5792 location_t saved_loc = input_location;
5794 /* Now that we've got all the field declarations, reverse everything
5796 unreverse_member_declarations (t);
5798 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5800 /* Nadger the current location so that diagnostics point to the start of
5801 the struct, not the end. */
5802 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5804 if (processing_template_decl)
5808 finish_struct_methods (t);
5809 TYPE_SIZE (t) = bitsize_zero_node;
5810 TYPE_SIZE_UNIT (t) = size_zero_node;
5812 /* We need to emit an error message if this type was used as a parameter
5813 and it is an abstract type, even if it is a template. We construct
5814 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5815 account and we call complete_vars with this type, which will check
5816 the PARM_DECLS. Note that while the type is being defined,
5817 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5818 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5819 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5820 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
5821 if (DECL_PURE_VIRTUAL_P (x))
5822 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5825 /* Remember current #pragma pack value. */
5826 TYPE_PRECISION (t) = maximum_field_alignment;
5829 finish_struct_1 (t);
5831 input_location = saved_loc;
5833 TYPE_BEING_DEFINED (t) = 0;
5835 if (current_class_type)
5838 error ("trying to finish struct, but kicked out due to previous parse errors");
5840 if (processing_template_decl && at_function_scope_p ())
5841 add_stmt (build_min (TAG_DEFN, t));
5846 /* Return the dynamic type of INSTANCE, if known.
5847 Used to determine whether the virtual function table is needed
5850 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5851 of our knowledge of its type. *NONNULL should be initialized
5852 before this function is called. */
5855 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5857 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5859 switch (TREE_CODE (instance))
5862 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5865 return RECUR (TREE_OPERAND (instance, 0));
5868 /* This is a call to a constructor, hence it's never zero. */
5869 if (TREE_HAS_CONSTRUCTOR (instance))
5873 return TREE_TYPE (instance);
5878 /* This is a call to a constructor, hence it's never zero. */
5879 if (TREE_HAS_CONSTRUCTOR (instance))
5883 return TREE_TYPE (instance);
5885 return RECUR (TREE_OPERAND (instance, 0));
5887 case POINTER_PLUS_EXPR:
5890 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5891 return RECUR (TREE_OPERAND (instance, 0));
5892 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5893 /* Propagate nonnull. */
5894 return RECUR (TREE_OPERAND (instance, 0));
5899 return RECUR (TREE_OPERAND (instance, 0));
5902 instance = TREE_OPERAND (instance, 0);
5905 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5906 with a real object -- given &p->f, p can still be null. */
5907 tree t = get_base_address (instance);
5908 /* ??? Probably should check DECL_WEAK here. */
5909 if (t && DECL_P (t))
5912 return RECUR (instance);
5915 /* If this component is really a base class reference, then the field
5916 itself isn't definitive. */
5917 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5918 return RECUR (TREE_OPERAND (instance, 0));
5919 return RECUR (TREE_OPERAND (instance, 1));
5923 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5924 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
5928 return TREE_TYPE (TREE_TYPE (instance));
5930 /* fall through... */
5934 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
5938 return TREE_TYPE (instance);
5940 else if (instance == current_class_ptr)
5945 /* if we're in a ctor or dtor, we know our type. */
5946 if (DECL_LANG_SPECIFIC (current_function_decl)
5947 && (DECL_CONSTRUCTOR_P (current_function_decl)
5948 || DECL_DESTRUCTOR_P (current_function_decl)))
5952 return TREE_TYPE (TREE_TYPE (instance));
5955 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5957 /* We only need one hash table because it is always left empty. */
5960 ht = htab_create (37,
5965 /* Reference variables should be references to objects. */
5969 /* Enter the INSTANCE in a table to prevent recursion; a
5970 variable's initializer may refer to the variable
5972 if (TREE_CODE (instance) == VAR_DECL
5973 && DECL_INITIAL (instance)
5974 && !type_dependent_expression_p_push (DECL_INITIAL (instance))
5975 && !htab_find (ht, instance))
5980 slot = htab_find_slot (ht, instance, INSERT);
5982 type = RECUR (DECL_INITIAL (instance));
5983 htab_remove_elt (ht, instance);
5996 /* Return nonzero if the dynamic type of INSTANCE is known, and
5997 equivalent to the static type. We also handle the case where
5998 INSTANCE is really a pointer. Return negative if this is a
5999 ctor/dtor. There the dynamic type is known, but this might not be
6000 the most derived base of the original object, and hence virtual
6001 bases may not be layed out according to this type.
6003 Used to determine whether the virtual function table is needed
6006 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6007 of our knowledge of its type. *NONNULL should be initialized
6008 before this function is called. */
6011 resolves_to_fixed_type_p (tree instance, int* nonnull)
6013 tree t = TREE_TYPE (instance);
6017 if (processing_template_decl)
6019 /* In a template we only care about the type of the result. */
6025 fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
6026 if (fixed == NULL_TREE)
6028 if (POINTER_TYPE_P (t))
6030 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
6032 return cdtorp ? -1 : 1;
6037 init_class_processing (void)
6039 current_class_depth = 0;
6040 current_class_stack_size = 10;
6042 = XNEWVEC (struct class_stack_node, current_class_stack_size);
6043 local_classes = VEC_alloc (tree, gc, 8);
6044 sizeof_biggest_empty_class = size_zero_node;
6046 ridpointers[(int) RID_PUBLIC] = access_public_node;
6047 ridpointers[(int) RID_PRIVATE] = access_private_node;
6048 ridpointers[(int) RID_PROTECTED] = access_protected_node;
6051 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
6054 restore_class_cache (void)
6058 /* We are re-entering the same class we just left, so we don't
6059 have to search the whole inheritance matrix to find all the
6060 decls to bind again. Instead, we install the cached
6061 class_shadowed list and walk through it binding names. */
6062 push_binding_level (previous_class_level);
6063 class_binding_level = previous_class_level;
6064 /* Restore IDENTIFIER_TYPE_VALUE. */
6065 for (type = class_binding_level->type_shadowed;
6067 type = TREE_CHAIN (type))
6068 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
6071 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
6072 appropriate for TYPE.
6074 So that we may avoid calls to lookup_name, we cache the _TYPE
6075 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
6077 For use by push_access_scope, we allow TYPE to be null to temporarily
6078 push out of class scope. This does not actually change binding levels.
6080 For multiple inheritance, we perform a two-pass depth-first search
6081 of the type lattice. */
6084 pushclass (tree type)
6086 class_stack_node_t csn;
6088 /* Make sure there is enough room for the new entry on the stack. */
6089 if (current_class_depth + 1 >= current_class_stack_size)
6091 current_class_stack_size *= 2;
6093 = XRESIZEVEC (struct class_stack_node, current_class_stack,
6094 current_class_stack_size);
6097 /* Insert a new entry on the class stack. */
6098 csn = current_class_stack + current_class_depth;
6099 csn->name = current_class_name;
6100 csn->type = current_class_type;
6101 csn->access = current_access_specifier;
6102 csn->names_used = 0;
6104 current_class_depth++;
6106 if (type == NULL_TREE)
6108 current_class_name = current_class_type = NULL_TREE;
6113 type = TYPE_MAIN_VARIANT (type);
6115 /* Now set up the new type. */
6116 current_class_name = TYPE_NAME (type);
6117 if (TREE_CODE (current_class_name) == TYPE_DECL)
6118 current_class_name = DECL_NAME (current_class_name);
6119 current_class_type = type;
6121 /* By default, things in classes are private, while things in
6122 structures or unions are public. */
6123 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
6124 ? access_private_node
6125 : access_public_node);
6127 if (previous_class_level
6128 && type != previous_class_level->this_entity
6129 && current_class_depth == 1)
6131 /* Forcibly remove any old class remnants. */
6132 invalidate_class_lookup_cache ();
6135 if (!previous_class_level
6136 || type != previous_class_level->this_entity
6137 || current_class_depth > 1)
6140 restore_class_cache ();
6143 /* When we exit a toplevel class scope, we save its binding level so
6144 that we can restore it quickly. Here, we've entered some other
6145 class, so we must invalidate our cache. */
6148 invalidate_class_lookup_cache (void)
6150 previous_class_level = NULL;
6153 /* Get out of the current class scope. If we were in a class scope
6154 previously, that is the one popped to. */
6159 if (current_class_type)
6162 gcc_assert (current_class_depth
6163 && current_class_stack[current_class_depth - 1].hidden);
6165 current_class_depth--;
6166 current_class_name = current_class_stack[current_class_depth].name;
6167 current_class_type = current_class_stack[current_class_depth].type;
6168 current_access_specifier = current_class_stack[current_class_depth].access;
6169 if (current_class_stack[current_class_depth].names_used)
6170 splay_tree_delete (current_class_stack[current_class_depth].names_used);
6173 /* Mark the top of the class stack as hidden. */
6176 push_class_stack (void)
6178 if (current_class_depth)
6179 ++current_class_stack[current_class_depth - 1].hidden;
6182 /* Mark the top of the class stack as un-hidden. */
6185 pop_class_stack (void)
6187 if (current_class_depth)
6188 --current_class_stack[current_class_depth - 1].hidden;
6191 /* Returns 1 if the class type currently being defined is either T or
6192 a nested type of T. */
6195 currently_open_class (tree t)
6199 if (!CLASS_TYPE_P (t))
6202 t = TYPE_MAIN_VARIANT (t);
6204 /* We start looking from 1 because entry 0 is from global scope,
6206 for (i = current_class_depth; i > 0; --i)
6209 if (i == current_class_depth)
6210 c = current_class_type;
6213 if (current_class_stack[i].hidden)
6215 c = current_class_stack[i].type;
6219 if (same_type_p (c, t))
6225 /* If either current_class_type or one of its enclosing classes are derived
6226 from T, return the appropriate type. Used to determine how we found
6227 something via unqualified lookup. */
6230 currently_open_derived_class (tree t)
6234 /* The bases of a dependent type are unknown. */
6235 if (dependent_type_p (t))
6238 if (!current_class_type)
6241 if (DERIVED_FROM_P (t, current_class_type))
6242 return current_class_type;
6244 for (i = current_class_depth - 1; i > 0; --i)
6246 if (current_class_stack[i].hidden)
6248 if (DERIVED_FROM_P (t, current_class_stack[i].type))
6249 return current_class_stack[i].type;
6255 /* Returns the innermost class type which is not a lambda closure type. */
6258 current_nonlambda_class_type (void)
6262 /* We start looking from 1 because entry 0 is from global scope,
6264 for (i = current_class_depth; i > 0; --i)
6267 if (i == current_class_depth)
6268 c = current_class_type;
6271 if (current_class_stack[i].hidden)
6273 c = current_class_stack[i].type;
6277 if (!LAMBDA_TYPE_P (c))
6283 /* When entering a class scope, all enclosing class scopes' names with
6284 static meaning (static variables, static functions, types and
6285 enumerators) have to be visible. This recursive function calls
6286 pushclass for all enclosing class contexts until global or a local
6287 scope is reached. TYPE is the enclosed class. */
6290 push_nested_class (tree type)
6292 /* A namespace might be passed in error cases, like A::B:C. */
6293 if (type == NULL_TREE
6294 || !CLASS_TYPE_P (type))
6297 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
6302 /* Undoes a push_nested_class call. */
6305 pop_nested_class (void)
6307 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
6310 if (context && CLASS_TYPE_P (context))
6311 pop_nested_class ();
6314 /* Returns the number of extern "LANG" blocks we are nested within. */
6317 current_lang_depth (void)
6319 return VEC_length (tree, current_lang_base);
6322 /* Set global variables CURRENT_LANG_NAME to appropriate value
6323 so that behavior of name-mangling machinery is correct. */
6326 push_lang_context (tree name)
6328 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
6330 if (name == lang_name_cplusplus)
6332 current_lang_name = name;
6334 else if (name == lang_name_java)
6336 current_lang_name = name;
6337 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6338 (See record_builtin_java_type in decl.c.) However, that causes
6339 incorrect debug entries if these types are actually used.
6340 So we re-enable debug output after extern "Java". */
6341 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
6342 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
6343 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
6344 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
6345 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
6346 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
6347 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
6348 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
6350 else if (name == lang_name_c)
6352 current_lang_name = name;
6355 error ("language string %<\"%E\"%> not recognized", name);
6358 /* Get out of the current language scope. */
6361 pop_lang_context (void)
6363 current_lang_name = VEC_pop (tree, current_lang_base);
6366 /* Type instantiation routines. */
6368 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6369 matches the TARGET_TYPE. If there is no satisfactory match, return
6370 error_mark_node, and issue an error & warning messages under
6371 control of FLAGS. Permit pointers to member function if FLAGS
6372 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6373 a template-id, and EXPLICIT_TARGS are the explicitly provided
6376 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6377 is the base path used to reference those member functions. If
6378 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6379 resolved to a member function, access checks will be performed and
6380 errors issued if appropriate. */
6383 resolve_address_of_overloaded_function (tree target_type,
6385 tsubst_flags_t flags,
6387 tree explicit_targs,
6390 /* Here's what the standard says:
6394 If the name is a function template, template argument deduction
6395 is done, and if the argument deduction succeeds, the deduced
6396 arguments are used to generate a single template function, which
6397 is added to the set of overloaded functions considered.
6399 Non-member functions and static member functions match targets of
6400 type "pointer-to-function" or "reference-to-function." Nonstatic
6401 member functions match targets of type "pointer-to-member
6402 function;" the function type of the pointer to member is used to
6403 select the member function from the set of overloaded member
6404 functions. If a nonstatic member function is selected, the
6405 reference to the overloaded function name is required to have the
6406 form of a pointer to member as described in 5.3.1.
6408 If more than one function is selected, any template functions in
6409 the set are eliminated if the set also contains a non-template
6410 function, and any given template function is eliminated if the
6411 set contains a second template function that is more specialized
6412 than the first according to the partial ordering rules 14.5.5.2.
6413 After such eliminations, if any, there shall remain exactly one
6414 selected function. */
6417 /* We store the matches in a TREE_LIST rooted here. The functions
6418 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6419 interoperability with most_specialized_instantiation. */
6420 tree matches = NULL_TREE;
6422 tree target_fn_type;
6424 /* By the time we get here, we should be seeing only real
6425 pointer-to-member types, not the internal POINTER_TYPE to
6426 METHOD_TYPE representation. */
6427 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6428 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6430 gcc_assert (is_overloaded_fn (overload));
6432 /* Check that the TARGET_TYPE is reasonable. */
6433 if (TYPE_PTRFN_P (target_type))
6435 else if (TYPE_PTRMEMFUNC_P (target_type))
6436 /* This is OK, too. */
6438 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6439 /* This is OK, too. This comes from a conversion to reference
6441 target_type = build_reference_type (target_type);
6444 if (flags & tf_error)
6445 error ("cannot resolve overloaded function %qD based on"
6446 " conversion to type %qT",
6447 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6448 return error_mark_node;
6451 /* Non-member functions and static member functions match targets of type
6452 "pointer-to-function" or "reference-to-function." Nonstatic member
6453 functions match targets of type "pointer-to-member-function;" the
6454 function type of the pointer to member is used to select the member
6455 function from the set of overloaded member functions.
6457 So figure out the FUNCTION_TYPE that we want to match against. */
6458 target_fn_type = static_fn_type (target_type);
6460 /* If we can find a non-template function that matches, we can just
6461 use it. There's no point in generating template instantiations
6462 if we're just going to throw them out anyhow. But, of course, we
6463 can only do this when we don't *need* a template function. */
6468 for (fns = overload; fns; fns = OVL_NEXT (fns))
6470 tree fn = OVL_CURRENT (fns);
6472 if (TREE_CODE (fn) == TEMPLATE_DECL)
6473 /* We're not looking for templates just yet. */
6476 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6478 /* We're looking for a non-static member, and this isn't
6479 one, or vice versa. */
6482 /* Ignore functions which haven't been explicitly
6484 if (DECL_ANTICIPATED (fn))
6487 /* See if there's a match. */
6488 if (same_type_p (target_fn_type, static_fn_type (fn)))
6489 matches = tree_cons (fn, NULL_TREE, matches);
6493 /* Now, if we've already got a match (or matches), there's no need
6494 to proceed to the template functions. But, if we don't have a
6495 match we need to look at them, too. */
6498 tree target_arg_types;
6499 tree target_ret_type;
6502 unsigned int nargs, ia;
6505 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6506 target_ret_type = TREE_TYPE (target_fn_type);
6508 nargs = list_length (target_arg_types);
6509 args = XALLOCAVEC (tree, nargs);
6510 for (arg = target_arg_types, ia = 0;
6511 arg != NULL_TREE && arg != void_list_node;
6512 arg = TREE_CHAIN (arg), ++ia)
6513 args[ia] = TREE_VALUE (arg);
6516 for (fns = overload; fns; fns = OVL_NEXT (fns))
6518 tree fn = OVL_CURRENT (fns);
6522 if (TREE_CODE (fn) != TEMPLATE_DECL)
6523 /* We're only looking for templates. */
6526 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6528 /* We're not looking for a non-static member, and this is
6529 one, or vice versa. */
6532 /* Try to do argument deduction. */
6533 targs = make_tree_vec (DECL_NTPARMS (fn));
6534 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6535 target_ret_type, DEDUCE_EXACT,
6537 /* Argument deduction failed. */
6540 /* Instantiate the template. */
6541 instantiation = instantiate_template (fn, targs, flags);
6542 if (instantiation == error_mark_node)
6543 /* Instantiation failed. */
6546 /* See if there's a match. */
6547 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
6548 matches = tree_cons (instantiation, fn, matches);
6551 /* Now, remove all but the most specialized of the matches. */
6554 tree match = most_specialized_instantiation (matches);
6556 if (match != error_mark_node)
6557 matches = tree_cons (TREE_PURPOSE (match),
6563 /* Now we should have exactly one function in MATCHES. */
6564 if (matches == NULL_TREE)
6566 /* There were *no* matches. */
6567 if (flags & tf_error)
6569 error ("no matches converting function %qD to type %q#T",
6570 DECL_NAME (OVL_CURRENT (overload)),
6573 print_candidates (overload);
6575 return error_mark_node;
6577 else if (TREE_CHAIN (matches))
6579 /* There were too many matches. First check if they're all
6580 the same function. */
6583 fn = TREE_PURPOSE (matches);
6584 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6585 if (!decls_match (fn, TREE_PURPOSE (match)))
6590 if (flags & tf_error)
6592 error ("converting overloaded function %qD to type %q#T is ambiguous",
6593 DECL_NAME (OVL_FUNCTION (overload)),
6596 /* Since print_candidates expects the functions in the
6597 TREE_VALUE slot, we flip them here. */
6598 for (match = matches; match; match = TREE_CHAIN (match))
6599 TREE_VALUE (match) = TREE_PURPOSE (match);
6601 print_candidates (matches);
6604 return error_mark_node;
6608 /* Good, exactly one match. Now, convert it to the correct type. */
6609 fn = TREE_PURPOSE (matches);
6611 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6612 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6614 static int explained;
6616 if (!(flags & tf_error))
6617 return error_mark_node;
6619 permerror (input_location, "assuming pointer to member %qD", fn);
6622 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6627 /* If we're doing overload resolution purely for the purpose of
6628 determining conversion sequences, we should not consider the
6629 function used. If this conversion sequence is selected, the
6630 function will be marked as used at this point. */
6631 if (!(flags & tf_conv))
6633 /* Make =delete work with SFINAE. */
6634 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6635 return error_mark_node;
6640 /* We could not check access to member functions when this
6641 expression was originally created since we did not know at that
6642 time to which function the expression referred. */
6643 if (!(flags & tf_no_access_control)
6644 && DECL_FUNCTION_MEMBER_P (fn))
6646 gcc_assert (access_path);
6647 perform_or_defer_access_check (access_path, fn, fn);
6650 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6651 return cp_build_addr_expr (fn, flags);
6654 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6655 will mark the function as addressed, but here we must do it
6657 cxx_mark_addressable (fn);
6663 /* This function will instantiate the type of the expression given in
6664 RHS to match the type of LHSTYPE. If errors exist, then return
6665 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6666 we complain on errors. If we are not complaining, never modify rhs,
6667 as overload resolution wants to try many possible instantiations, in
6668 the hope that at least one will work.
6670 For non-recursive calls, LHSTYPE should be a function, pointer to
6671 function, or a pointer to member function. */
6674 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6676 tsubst_flags_t flags_in = flags;
6677 tree access_path = NULL_TREE;
6679 flags &= ~tf_ptrmem_ok;
6681 if (lhstype == unknown_type_node)
6683 if (flags & tf_error)
6684 error ("not enough type information");
6685 return error_mark_node;
6688 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6690 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6692 if (flag_ms_extensions
6693 && TYPE_PTRMEMFUNC_P (lhstype)
6694 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6695 /* Microsoft allows `A::f' to be resolved to a
6696 pointer-to-member. */
6700 if (flags & tf_error)
6701 error ("argument of type %qT does not match %qT",
6702 TREE_TYPE (rhs), lhstype);
6703 return error_mark_node;
6707 if (TREE_CODE (rhs) == BASELINK)
6709 access_path = BASELINK_ACCESS_BINFO (rhs);
6710 rhs = BASELINK_FUNCTIONS (rhs);
6713 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6714 deduce any type information. */
6715 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6717 if (flags & tf_error)
6718 error ("not enough type information");
6719 return error_mark_node;
6722 /* There only a few kinds of expressions that may have a type
6723 dependent on overload resolution. */
6724 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6725 || TREE_CODE (rhs) == COMPONENT_REF
6726 || really_overloaded_fn (rhs)
6727 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
6729 /* This should really only be used when attempting to distinguish
6730 what sort of a pointer to function we have. For now, any
6731 arithmetic operation which is not supported on pointers
6732 is rejected as an error. */
6734 switch (TREE_CODE (rhs))
6738 tree member = TREE_OPERAND (rhs, 1);
6740 member = instantiate_type (lhstype, member, flags);
6741 if (member != error_mark_node
6742 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6743 /* Do not lose object's side effects. */
6744 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6745 TREE_OPERAND (rhs, 0), member);
6750 rhs = TREE_OPERAND (rhs, 1);
6751 if (BASELINK_P (rhs))
6752 return instantiate_type (lhstype, rhs, flags_in);
6754 /* This can happen if we are forming a pointer-to-member for a
6756 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6760 case TEMPLATE_ID_EXPR:
6762 tree fns = TREE_OPERAND (rhs, 0);
6763 tree args = TREE_OPERAND (rhs, 1);
6766 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6767 /*template_only=*/true,
6774 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6775 /*template_only=*/false,
6776 /*explicit_targs=*/NULL_TREE,
6781 if (PTRMEM_OK_P (rhs))
6782 flags |= tf_ptrmem_ok;
6784 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6788 return error_mark_node;
6793 return error_mark_node;
6796 /* Return the name of the virtual function pointer field
6797 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6798 this may have to look back through base types to find the
6799 ultimate field name. (For single inheritance, these could
6800 all be the same name. Who knows for multiple inheritance). */
6803 get_vfield_name (tree type)
6805 tree binfo, base_binfo;
6808 for (binfo = TYPE_BINFO (type);
6809 BINFO_N_BASE_BINFOS (binfo);
6812 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6814 if (BINFO_VIRTUAL_P (base_binfo)
6815 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6819 type = BINFO_TYPE (binfo);
6820 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6821 + TYPE_NAME_LENGTH (type) + 2);
6822 sprintf (buf, VFIELD_NAME_FORMAT,
6823 IDENTIFIER_POINTER (constructor_name (type)));
6824 return get_identifier (buf);
6828 print_class_statistics (void)
6830 #ifdef GATHER_STATISTICS
6831 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6832 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6835 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6836 n_vtables, n_vtable_searches);
6837 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6838 n_vtable_entries, n_vtable_elems);
6843 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6844 according to [class]:
6845 The class-name is also inserted
6846 into the scope of the class itself. For purposes of access checking,
6847 the inserted class name is treated as if it were a public member name. */
6850 build_self_reference (void)
6852 tree name = constructor_name (current_class_type);
6853 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6856 DECL_NONLOCAL (value) = 1;
6857 DECL_CONTEXT (value) = current_class_type;
6858 DECL_ARTIFICIAL (value) = 1;
6859 SET_DECL_SELF_REFERENCE_P (value);
6860 set_underlying_type (value);
6862 if (processing_template_decl)
6863 value = push_template_decl (value);
6865 saved_cas = current_access_specifier;
6866 current_access_specifier = access_public_node;
6867 finish_member_declaration (value);
6868 current_access_specifier = saved_cas;
6871 /* Returns 1 if TYPE contains only padding bytes. */
6874 is_empty_class (tree type)
6876 if (type == error_mark_node)
6879 if (! CLASS_TYPE_P (type))
6882 /* In G++ 3.2, whether or not a class was empty was determined by
6883 looking at its size. */
6884 if (abi_version_at_least (2))
6885 return CLASSTYPE_EMPTY_P (type);
6887 return integer_zerop (CLASSTYPE_SIZE (type));
6890 /* Returns true if TYPE contains an empty class. */
6893 contains_empty_class_p (tree type)
6895 if (is_empty_class (type))
6897 if (CLASS_TYPE_P (type))
6904 for (binfo = TYPE_BINFO (type), i = 0;
6905 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6906 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6908 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6909 if (TREE_CODE (field) == FIELD_DECL
6910 && !DECL_ARTIFICIAL (field)
6911 && is_empty_class (TREE_TYPE (field)))
6914 else if (TREE_CODE (type) == ARRAY_TYPE)
6915 return contains_empty_class_p (TREE_TYPE (type));
6919 /* Returns true if TYPE contains no actual data, just various
6920 possible combinations of empty classes and possibly a vptr. */
6923 is_really_empty_class (tree type)
6925 if (CLASS_TYPE_P (type))
6932 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
6933 out, but we'd like to be able to check this before then. */
6934 if (COMPLETE_TYPE_P (type) && is_empty_class (type))
6937 for (binfo = TYPE_BINFO (type), i = 0;
6938 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6939 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
6941 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
6942 if (TREE_CODE (field) == FIELD_DECL
6943 && !DECL_ARTIFICIAL (field)
6944 && !is_really_empty_class (TREE_TYPE (field)))
6948 else if (TREE_CODE (type) == ARRAY_TYPE)
6949 return is_really_empty_class (TREE_TYPE (type));
6953 /* Note that NAME was looked up while the current class was being
6954 defined and that the result of that lookup was DECL. */
6957 maybe_note_name_used_in_class (tree name, tree decl)
6959 splay_tree names_used;
6961 /* If we're not defining a class, there's nothing to do. */
6962 if (!(innermost_scope_kind() == sk_class
6963 && TYPE_BEING_DEFINED (current_class_type)
6964 && !LAMBDA_TYPE_P (current_class_type)))
6967 /* If there's already a binding for this NAME, then we don't have
6968 anything to worry about. */
6969 if (lookup_member (current_class_type, name,
6970 /*protect=*/0, /*want_type=*/false))
6973 if (!current_class_stack[current_class_depth - 1].names_used)
6974 current_class_stack[current_class_depth - 1].names_used
6975 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6976 names_used = current_class_stack[current_class_depth - 1].names_used;
6978 splay_tree_insert (names_used,
6979 (splay_tree_key) name,
6980 (splay_tree_value) decl);
6983 /* Note that NAME was declared (as DECL) in the current class. Check
6984 to see that the declaration is valid. */
6987 note_name_declared_in_class (tree name, tree decl)
6989 splay_tree names_used;
6992 /* Look to see if we ever used this name. */
6994 = current_class_stack[current_class_depth - 1].names_used;
6997 /* The C language allows members to be declared with a type of the same
6998 name, and the C++ standard says this diagnostic is not required. So
6999 allow it in extern "C" blocks unless predantic is specified.
7000 Allow it in all cases if -ms-extensions is specified. */
7001 if ((!pedantic && current_lang_name == lang_name_c)
7002 || flag_ms_extensions)
7004 n = splay_tree_lookup (names_used, (splay_tree_key) name);
7007 /* [basic.scope.class]
7009 A name N used in a class S shall refer to the same declaration
7010 in its context and when re-evaluated in the completed scope of
7012 permerror (input_location, "declaration of %q#D", decl);
7013 permerror (input_location, "changes meaning of %qD from %q+#D",
7014 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
7018 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
7019 Secondary vtables are merged with primary vtables; this function
7020 will return the VAR_DECL for the primary vtable. */
7023 get_vtbl_decl_for_binfo (tree binfo)
7027 decl = BINFO_VTABLE (binfo);
7028 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
7030 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
7031 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
7034 gcc_assert (TREE_CODE (decl) == VAR_DECL);
7039 /* Returns the binfo for the primary base of BINFO. If the resulting
7040 BINFO is a virtual base, and it is inherited elsewhere in the
7041 hierarchy, then the returned binfo might not be the primary base of
7042 BINFO in the complete object. Check BINFO_PRIMARY_P or
7043 BINFO_LOST_PRIMARY_P to be sure. */
7046 get_primary_binfo (tree binfo)
7050 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
7054 return copied_binfo (primary_base, binfo);
7057 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
7060 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
7063 fprintf (stream, "%*s", indent, "");
7067 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
7068 INDENT should be zero when called from the top level; it is
7069 incremented recursively. IGO indicates the next expected BINFO in
7070 inheritance graph ordering. */
7073 dump_class_hierarchy_r (FILE *stream,
7083 indented = maybe_indent_hierarchy (stream, indent, 0);
7084 fprintf (stream, "%s (0x%lx) ",
7085 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
7086 (unsigned long) binfo);
7089 fprintf (stream, "alternative-path\n");
7092 igo = TREE_CHAIN (binfo);
7094 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
7095 tree_low_cst (BINFO_OFFSET (binfo), 0));
7096 if (is_empty_class (BINFO_TYPE (binfo)))
7097 fprintf (stream, " empty");
7098 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
7099 fprintf (stream, " nearly-empty");
7100 if (BINFO_VIRTUAL_P (binfo))
7101 fprintf (stream, " virtual");
7102 fprintf (stream, "\n");
7105 if (BINFO_PRIMARY_P (binfo))
7107 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7108 fprintf (stream, " primary-for %s (0x%lx)",
7109 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
7110 TFF_PLAIN_IDENTIFIER),
7111 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
7113 if (BINFO_LOST_PRIMARY_P (binfo))
7115 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7116 fprintf (stream, " lost-primary");
7119 fprintf (stream, "\n");
7121 if (!(flags & TDF_SLIM))
7125 if (BINFO_SUBVTT_INDEX (binfo))
7127 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7128 fprintf (stream, " subvttidx=%s",
7129 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
7130 TFF_PLAIN_IDENTIFIER));
7132 if (BINFO_VPTR_INDEX (binfo))
7134 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7135 fprintf (stream, " vptridx=%s",
7136 expr_as_string (BINFO_VPTR_INDEX (binfo),
7137 TFF_PLAIN_IDENTIFIER));
7139 if (BINFO_VPTR_FIELD (binfo))
7141 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7142 fprintf (stream, " vbaseoffset=%s",
7143 expr_as_string (BINFO_VPTR_FIELD (binfo),
7144 TFF_PLAIN_IDENTIFIER));
7146 if (BINFO_VTABLE (binfo))
7148 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7149 fprintf (stream, " vptr=%s",
7150 expr_as_string (BINFO_VTABLE (binfo),
7151 TFF_PLAIN_IDENTIFIER));
7155 fprintf (stream, "\n");
7158 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
7159 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
7164 /* Dump the BINFO hierarchy for T. */
7167 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
7169 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7170 fprintf (stream, " size=%lu align=%lu\n",
7171 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
7172 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
7173 fprintf (stream, " base size=%lu base align=%lu\n",
7174 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
7176 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
7178 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
7179 fprintf (stream, "\n");
7182 /* Debug interface to hierarchy dumping. */
7185 debug_class (tree t)
7187 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
7191 dump_class_hierarchy (tree t)
7194 FILE *stream = dump_begin (TDI_class, &flags);
7198 dump_class_hierarchy_1 (stream, flags, t);
7199 dump_end (TDI_class, stream);
7204 dump_array (FILE * stream, tree decl)
7207 unsigned HOST_WIDE_INT ix;
7209 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
7211 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
7213 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
7214 fprintf (stream, " %s entries",
7215 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
7216 TFF_PLAIN_IDENTIFIER));
7217 fprintf (stream, "\n");
7219 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
7221 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
7222 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
7226 dump_vtable (tree t, tree binfo, tree vtable)
7229 FILE *stream = dump_begin (TDI_class, &flags);
7234 if (!(flags & TDF_SLIM))
7236 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
7238 fprintf (stream, "%s for %s",
7239 ctor_vtbl_p ? "Construction vtable" : "Vtable",
7240 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
7243 if (!BINFO_VIRTUAL_P (binfo))
7244 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
7245 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7247 fprintf (stream, "\n");
7248 dump_array (stream, vtable);
7249 fprintf (stream, "\n");
7252 dump_end (TDI_class, stream);
7256 dump_vtt (tree t, tree vtt)
7259 FILE *stream = dump_begin (TDI_class, &flags);
7264 if (!(flags & TDF_SLIM))
7266 fprintf (stream, "VTT for %s\n",
7267 type_as_string (t, TFF_PLAIN_IDENTIFIER));
7268 dump_array (stream, vtt);
7269 fprintf (stream, "\n");
7272 dump_end (TDI_class, stream);
7275 /* Dump a function or thunk and its thunkees. */
7278 dump_thunk (FILE *stream, int indent, tree thunk)
7280 static const char spaces[] = " ";
7281 tree name = DECL_NAME (thunk);
7284 fprintf (stream, "%.*s%p %s %s", indent, spaces,
7286 !DECL_THUNK_P (thunk) ? "function"
7287 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
7288 name ? IDENTIFIER_POINTER (name) : "<unset>");
7289 if (DECL_THUNK_P (thunk))
7291 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
7292 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
7294 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
7295 if (!virtual_adjust)
7297 else if (DECL_THIS_THUNK_P (thunk))
7298 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
7299 tree_low_cst (virtual_adjust, 0));
7301 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
7302 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
7303 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
7304 if (THUNK_ALIAS (thunk))
7305 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
7307 fprintf (stream, "\n");
7308 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
7309 dump_thunk (stream, indent + 2, thunks);
7312 /* Dump the thunks for FN. */
7315 debug_thunks (tree fn)
7317 dump_thunk (stderr, 0, fn);
7320 /* Virtual function table initialization. */
7322 /* Create all the necessary vtables for T and its base classes. */
7325 finish_vtbls (tree t)
7328 VEC(constructor_elt,gc) *v = NULL;
7329 tree vtable = BINFO_VTABLE (TYPE_BINFO (t));
7331 /* We lay out the primary and secondary vtables in one contiguous
7332 vtable. The primary vtable is first, followed by the non-virtual
7333 secondary vtables in inheritance graph order. */
7334 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t),
7337 /* Then come the virtual bases, also in inheritance graph order. */
7338 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
7340 if (!BINFO_VIRTUAL_P (vbase))
7342 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), vtable, t, &v);
7345 if (BINFO_VTABLE (TYPE_BINFO (t)))
7346 initialize_vtable (TYPE_BINFO (t), v);
7349 /* Initialize the vtable for BINFO with the INITS. */
7352 initialize_vtable (tree binfo, VEC(constructor_elt,gc) *inits)
7356 layout_vtable_decl (binfo, VEC_length (constructor_elt, inits));
7357 decl = get_vtbl_decl_for_binfo (binfo);
7358 initialize_artificial_var (decl, inits);
7359 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
7362 /* Build the VTT (virtual table table) for T.
7363 A class requires a VTT if it has virtual bases.
7366 1 - primary virtual pointer for complete object T
7367 2 - secondary VTTs for each direct non-virtual base of T which requires a
7369 3 - secondary virtual pointers for each direct or indirect base of T which
7370 has virtual bases or is reachable via a virtual path from T.
7371 4 - secondary VTTs for each direct or indirect virtual base of T.
7373 Secondary VTTs look like complete object VTTs without part 4. */
7381 VEC(constructor_elt,gc) *inits;
7383 /* Build up the initializers for the VTT. */
7385 index = size_zero_node;
7386 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7388 /* If we didn't need a VTT, we're done. */
7392 /* Figure out the type of the VTT. */
7393 type = build_array_of_n_type (const_ptr_type_node,
7394 VEC_length (constructor_elt, inits));
7396 /* Now, build the VTT object itself. */
7397 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7398 initialize_artificial_var (vtt, inits);
7399 /* Add the VTT to the vtables list. */
7400 DECL_CHAIN (vtt) = DECL_CHAIN (CLASSTYPE_VTABLES (t));
7401 DECL_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7406 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7407 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7408 and CHAIN the vtable pointer for this binfo after construction is
7409 complete. VALUE can also be another BINFO, in which case we recurse. */
7412 binfo_ctor_vtable (tree binfo)
7418 vt = BINFO_VTABLE (binfo);
7419 if (TREE_CODE (vt) == TREE_LIST)
7420 vt = TREE_VALUE (vt);
7421 if (TREE_CODE (vt) == TREE_BINFO)
7430 /* Data for secondary VTT initialization. */
7431 typedef struct secondary_vptr_vtt_init_data_s
7433 /* Is this the primary VTT? */
7436 /* Current index into the VTT. */
7439 /* Vector of initializers built up. */
7440 VEC(constructor_elt,gc) *inits;
7442 /* The type being constructed by this secondary VTT. */
7443 tree type_being_constructed;
7444 } secondary_vptr_vtt_init_data;
7446 /* Recursively build the VTT-initializer for BINFO (which is in the
7447 hierarchy dominated by T). INITS points to the end of the initializer
7448 list to date. INDEX is the VTT index where the next element will be
7449 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7450 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7451 for virtual bases of T. When it is not so, we build the constructor
7452 vtables for the BINFO-in-T variant. */
7455 build_vtt_inits (tree binfo, tree t, VEC(constructor_elt,gc) **inits, tree *index)
7460 secondary_vptr_vtt_init_data data;
7461 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7463 /* We only need VTTs for subobjects with virtual bases. */
7464 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7467 /* We need to use a construction vtable if this is not the primary
7471 build_ctor_vtbl_group (binfo, t);
7473 /* Record the offset in the VTT where this sub-VTT can be found. */
7474 BINFO_SUBVTT_INDEX (binfo) = *index;
7477 /* Add the address of the primary vtable for the complete object. */
7478 init = binfo_ctor_vtable (binfo);
7479 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7482 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7483 BINFO_VPTR_INDEX (binfo) = *index;
7485 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7487 /* Recursively add the secondary VTTs for non-virtual bases. */
7488 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7489 if (!BINFO_VIRTUAL_P (b))
7490 build_vtt_inits (b, t, inits, index);
7492 /* Add secondary virtual pointers for all subobjects of BINFO with
7493 either virtual bases or reachable along a virtual path, except
7494 subobjects that are non-virtual primary bases. */
7495 data.top_level_p = top_level_p;
7496 data.index = *index;
7497 data.inits = *inits;
7498 data.type_being_constructed = BINFO_TYPE (binfo);
7500 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7502 *index = data.index;
7504 /* data.inits might have grown as we added secondary virtual pointers.
7505 Make sure our caller knows about the new vector. */
7506 *inits = data.inits;
7509 /* Add the secondary VTTs for virtual bases in inheritance graph
7511 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7513 if (!BINFO_VIRTUAL_P (b))
7516 build_vtt_inits (b, t, inits, index);
7519 /* Remove the ctor vtables we created. */
7520 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7523 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7524 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7527 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7529 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7531 /* We don't care about bases that don't have vtables. */
7532 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7533 return dfs_skip_bases;
7535 /* We're only interested in proper subobjects of the type being
7537 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7540 /* We're only interested in bases with virtual bases or reachable
7541 via a virtual path from the type being constructed. */
7542 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7543 || binfo_via_virtual (binfo, data->type_being_constructed)))
7544 return dfs_skip_bases;
7546 /* We're not interested in non-virtual primary bases. */
7547 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7550 /* Record the index where this secondary vptr can be found. */
7551 if (data->top_level_p)
7553 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7554 BINFO_VPTR_INDEX (binfo) = data->index;
7556 if (BINFO_VIRTUAL_P (binfo))
7558 /* It's a primary virtual base, and this is not a
7559 construction vtable. Find the base this is primary of in
7560 the inheritance graph, and use that base's vtable
7562 while (BINFO_PRIMARY_P (binfo))
7563 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7567 /* Add the initializer for the secondary vptr itself. */
7568 CONSTRUCTOR_APPEND_ELT (data->inits, NULL_TREE, binfo_ctor_vtable (binfo));
7570 /* Advance the vtt index. */
7571 data->index = size_binop (PLUS_EXPR, data->index,
7572 TYPE_SIZE_UNIT (ptr_type_node));
7577 /* Called from build_vtt_inits via dfs_walk. After building
7578 constructor vtables and generating the sub-vtt from them, we need
7579 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7580 binfo of the base whose sub vtt was generated. */
7583 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7585 tree vtable = BINFO_VTABLE (binfo);
7587 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7588 /* If this class has no vtable, none of its bases do. */
7589 return dfs_skip_bases;
7592 /* This might be a primary base, so have no vtable in this
7596 /* If we scribbled the construction vtable vptr into BINFO, clear it
7598 if (TREE_CODE (vtable) == TREE_LIST
7599 && (TREE_PURPOSE (vtable) == (tree) data))
7600 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7605 /* Build the construction vtable group for BINFO which is in the
7606 hierarchy dominated by T. */
7609 build_ctor_vtbl_group (tree binfo, tree t)
7615 VEC(constructor_elt,gc) *v;
7617 /* See if we've already created this construction vtable group. */
7618 id = mangle_ctor_vtbl_for_type (t, binfo);
7619 if (IDENTIFIER_GLOBAL_VALUE (id))
7622 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7623 /* Build a version of VTBL (with the wrong type) for use in
7624 constructing the addresses of secondary vtables in the
7625 construction vtable group. */
7626 vtbl = build_vtable (t, id, ptr_type_node);
7627 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7630 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7631 binfo, vtbl, t, &v);
7633 /* Add the vtables for each of our virtual bases using the vbase in T
7635 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7637 vbase = TREE_CHAIN (vbase))
7641 if (!BINFO_VIRTUAL_P (vbase))
7643 b = copied_binfo (vbase, binfo);
7645 accumulate_vtbl_inits (b, vbase, binfo, vtbl, t, &v);
7648 /* Figure out the type of the construction vtable. */
7649 type = build_array_of_n_type (vtable_entry_type,
7650 VEC_length (constructor_elt, v));
7652 TREE_TYPE (vtbl) = type;
7653 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7654 layout_decl (vtbl, 0);
7656 /* Initialize the construction vtable. */
7657 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7658 initialize_artificial_var (vtbl, v);
7659 dump_vtable (t, binfo, vtbl);
7662 /* Add the vtbl initializers for BINFO (and its bases other than
7663 non-virtual primaries) to the list of INITS. BINFO is in the
7664 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7665 the constructor the vtbl inits should be accumulated for. (If this
7666 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7667 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7668 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7669 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7670 but are not necessarily the same in terms of layout. */
7673 accumulate_vtbl_inits (tree binfo,
7678 VEC(constructor_elt,gc) **inits)
7682 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7684 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7686 /* If it doesn't have a vptr, we don't do anything. */
7687 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7690 /* If we're building a construction vtable, we're not interested in
7691 subobjects that don't require construction vtables. */
7693 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7694 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7697 /* Build the initializers for the BINFO-in-T vtable. */
7698 dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, vtbl, t, inits);
7700 /* Walk the BINFO and its bases. We walk in preorder so that as we
7701 initialize each vtable we can figure out at what offset the
7702 secondary vtable lies from the primary vtable. We can't use
7703 dfs_walk here because we need to iterate through bases of BINFO
7704 and RTTI_BINFO simultaneously. */
7705 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7707 /* Skip virtual bases. */
7708 if (BINFO_VIRTUAL_P (base_binfo))
7710 accumulate_vtbl_inits (base_binfo,
7711 BINFO_BASE_BINFO (orig_binfo, i),
7712 rtti_binfo, vtbl, t,
7717 /* Called from accumulate_vtbl_inits. Adds the initializers for the
7718 BINFO vtable to L. */
7721 dfs_accumulate_vtbl_inits (tree binfo,
7726 VEC(constructor_elt,gc) **l)
7728 tree vtbl = NULL_TREE;
7729 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7733 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7735 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7736 primary virtual base. If it is not the same primary in
7737 the hierarchy of T, we'll need to generate a ctor vtable
7738 for it, to place at its location in T. If it is the same
7739 primary, we still need a VTT entry for the vtable, but it
7740 should point to the ctor vtable for the base it is a
7741 primary for within the sub-hierarchy of RTTI_BINFO.
7743 There are three possible cases:
7745 1) We are in the same place.
7746 2) We are a primary base within a lost primary virtual base of
7748 3) We are primary to something not a base of RTTI_BINFO. */
7751 tree last = NULL_TREE;
7753 /* First, look through the bases we are primary to for RTTI_BINFO
7754 or a virtual base. */
7756 while (BINFO_PRIMARY_P (b))
7758 b = BINFO_INHERITANCE_CHAIN (b);
7760 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7763 /* If we run out of primary links, keep looking down our
7764 inheritance chain; we might be an indirect primary. */
7765 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7766 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7770 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7771 base B and it is a base of RTTI_BINFO, this is case 2. In
7772 either case, we share our vtable with LAST, i.e. the
7773 derived-most base within B of which we are a primary. */
7775 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7776 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7777 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7778 binfo_ctor_vtable after everything's been set up. */
7781 /* Otherwise, this is case 3 and we get our own. */
7783 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7786 n_inits = VEC_length (constructor_elt, *l);
7793 /* Add the initializer for this vtable. */
7794 build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7795 &non_fn_entries, l);
7797 /* Figure out the position to which the VPTR should point. */
7798 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, orig_vtbl);
7799 index = size_binop (PLUS_EXPR,
7800 size_int (non_fn_entries),
7801 size_int (n_inits));
7802 index = size_binop (MULT_EXPR,
7803 TYPE_SIZE_UNIT (vtable_entry_type),
7805 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7809 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7810 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7811 straighten this out. */
7812 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7813 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7814 /* Throw away any unneeded intializers. */
7815 VEC_truncate (constructor_elt, *l, n_inits);
7817 /* For an ordinary vtable, set BINFO_VTABLE. */
7818 BINFO_VTABLE (binfo) = vtbl;
7821 static GTY(()) tree abort_fndecl_addr;
7823 /* Construct the initializer for BINFO's virtual function table. BINFO
7824 is part of the hierarchy dominated by T. If we're building a
7825 construction vtable, the ORIG_BINFO is the binfo we should use to
7826 find the actual function pointers to put in the vtable - but they
7827 can be overridden on the path to most-derived in the graph that
7828 ORIG_BINFO belongs. Otherwise,
7829 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7830 BINFO that should be indicated by the RTTI information in the
7831 vtable; it will be a base class of T, rather than T itself, if we
7832 are building a construction vtable.
7834 The value returned is a TREE_LIST suitable for wrapping in a
7835 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7836 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7837 number of non-function entries in the vtable.
7839 It might seem that this function should never be called with a
7840 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7841 base is always subsumed by a derived class vtable. However, when
7842 we are building construction vtables, we do build vtables for
7843 primary bases; we need these while the primary base is being
7847 build_vtbl_initializer (tree binfo,
7851 int* non_fn_entries_p,
7852 VEC(constructor_elt,gc) **inits)
7858 VEC(tree,gc) *vbases;
7861 /* Initialize VID. */
7862 memset (&vid, 0, sizeof (vid));
7865 vid.rtti_binfo = rtti_binfo;
7866 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7867 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7868 vid.generate_vcall_entries = true;
7869 /* The first vbase or vcall offset is at index -3 in the vtable. */
7870 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7872 /* Add entries to the vtable for RTTI. */
7873 build_rtti_vtbl_entries (binfo, &vid);
7875 /* Create an array for keeping track of the functions we've
7876 processed. When we see multiple functions with the same
7877 signature, we share the vcall offsets. */
7878 vid.fns = VEC_alloc (tree, gc, 32);
7879 /* Add the vcall and vbase offset entries. */
7880 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7882 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7883 build_vbase_offset_vtbl_entries. */
7884 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7885 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7886 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7888 /* If the target requires padding between data entries, add that now. */
7889 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7891 int n_entries = VEC_length (constructor_elt, vid.inits);
7893 VEC_safe_grow (constructor_elt, gc, vid.inits,
7894 TARGET_VTABLE_DATA_ENTRY_DISTANCE * n_entries);
7896 /* Move data entries into their new positions and add padding
7897 after the new positions. Iterate backwards so we don't
7898 overwrite entries that we would need to process later. */
7899 for (ix = n_entries - 1;
7900 VEC_iterate (constructor_elt, vid.inits, ix, e);
7904 int new_position = (TARGET_VTABLE_DATA_ENTRY_DISTANCE * ix
7905 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE - 1));
7907 VEC_replace (constructor_elt, vid.inits, new_position, e);
7909 for (j = 1; j < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++j)
7911 constructor_elt *f = VEC_index (constructor_elt, vid.inits,
7913 f->index = NULL_TREE;
7914 f->value = build1 (NOP_EXPR, vtable_entry_type,
7920 if (non_fn_entries_p)
7921 *non_fn_entries_p = VEC_length (constructor_elt, vid.inits);
7923 /* The initializers for virtual functions were built up in reverse
7924 order. Straighten them out and add them to the running list in one
7926 jx = VEC_length (constructor_elt, *inits);
7927 VEC_safe_grow (constructor_elt, gc, *inits,
7928 (jx + VEC_length (constructor_elt, vid.inits)));
7930 for (ix = VEC_length (constructor_elt, vid.inits) - 1;
7931 VEC_iterate (constructor_elt, vid.inits, ix, e);
7933 VEC_replace (constructor_elt, *inits, jx, e);
7935 /* Go through all the ordinary virtual functions, building up
7937 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7941 tree fn, fn_original;
7942 tree init = NULL_TREE;
7946 if (DECL_THUNK_P (fn))
7948 if (!DECL_NAME (fn))
7950 if (THUNK_ALIAS (fn))
7952 fn = THUNK_ALIAS (fn);
7955 fn_original = THUNK_TARGET (fn);
7958 /* If the only definition of this function signature along our
7959 primary base chain is from a lost primary, this vtable slot will
7960 never be used, so just zero it out. This is important to avoid
7961 requiring extra thunks which cannot be generated with the function.
7963 We first check this in update_vtable_entry_for_fn, so we handle
7964 restored primary bases properly; we also need to do it here so we
7965 zero out unused slots in ctor vtables, rather than filling them
7966 with erroneous values (though harmless, apart from relocation
7968 if (BV_LOST_PRIMARY (v))
7969 init = size_zero_node;
7973 /* Pull the offset for `this', and the function to call, out of
7975 delta = BV_DELTA (v);
7976 vcall_index = BV_VCALL_INDEX (v);
7978 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7979 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7981 /* You can't call an abstract virtual function; it's abstract.
7982 So, we replace these functions with __pure_virtual. */
7983 if (DECL_PURE_VIRTUAL_P (fn_original))
7986 if (!TARGET_VTABLE_USES_DESCRIPTORS)
7988 if (abort_fndecl_addr == NULL)
7990 = fold_convert (vfunc_ptr_type_node,
7991 build_fold_addr_expr (fn));
7992 init = abort_fndecl_addr;
7997 if (!integer_zerop (delta) || vcall_index)
7999 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
8000 if (!DECL_NAME (fn))
8003 /* Take the address of the function, considering it to be of an
8004 appropriate generic type. */
8005 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8006 init = fold_convert (vfunc_ptr_type_node,
8007 build_fold_addr_expr (fn));
8011 /* And add it to the chain of initializers. */
8012 if (TARGET_VTABLE_USES_DESCRIPTORS)
8015 if (init == size_zero_node)
8016 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8017 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8019 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8021 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
8022 fn, build_int_cst (NULL_TREE, i));
8023 TREE_CONSTANT (fdesc) = 1;
8025 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, fdesc);
8029 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8033 /* Adds to vid->inits the initializers for the vbase and vcall
8034 offsets in BINFO, which is in the hierarchy dominated by T. */
8037 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
8041 /* If this is a derived class, we must first create entries
8042 corresponding to the primary base class. */
8043 b = get_primary_binfo (binfo);
8045 build_vcall_and_vbase_vtbl_entries (b, vid);
8047 /* Add the vbase entries for this base. */
8048 build_vbase_offset_vtbl_entries (binfo, vid);
8049 /* Add the vcall entries for this base. */
8050 build_vcall_offset_vtbl_entries (binfo, vid);
8053 /* Returns the initializers for the vbase offset entries in the vtable
8054 for BINFO (which is part of the class hierarchy dominated by T), in
8055 reverse order. VBASE_OFFSET_INDEX gives the vtable index
8056 where the next vbase offset will go. */
8059 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8063 tree non_primary_binfo;
8065 /* If there are no virtual baseclasses, then there is nothing to
8067 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
8072 /* We might be a primary base class. Go up the inheritance hierarchy
8073 until we find the most derived class of which we are a primary base:
8074 it is the offset of that which we need to use. */
8075 non_primary_binfo = binfo;
8076 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8080 /* If we have reached a virtual base, then it must be a primary
8081 base (possibly multi-level) of vid->binfo, or we wouldn't
8082 have called build_vcall_and_vbase_vtbl_entries for it. But it
8083 might be a lost primary, so just skip down to vid->binfo. */
8084 if (BINFO_VIRTUAL_P (non_primary_binfo))
8086 non_primary_binfo = vid->binfo;
8090 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8091 if (get_primary_binfo (b) != non_primary_binfo)
8093 non_primary_binfo = b;
8096 /* Go through the virtual bases, adding the offsets. */
8097 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
8099 vbase = TREE_CHAIN (vbase))
8104 if (!BINFO_VIRTUAL_P (vbase))
8107 /* Find the instance of this virtual base in the complete
8109 b = copied_binfo (vbase, binfo);
8111 /* If we've already got an offset for this virtual base, we
8112 don't need another one. */
8113 if (BINFO_VTABLE_PATH_MARKED (b))
8115 BINFO_VTABLE_PATH_MARKED (b) = 1;
8117 /* Figure out where we can find this vbase offset. */
8118 delta = size_binop (MULT_EXPR,
8121 TYPE_SIZE_UNIT (vtable_entry_type)));
8122 if (vid->primary_vtbl_p)
8123 BINFO_VPTR_FIELD (b) = delta;
8125 if (binfo != TYPE_BINFO (t))
8126 /* The vbase offset had better be the same. */
8127 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
8129 /* The next vbase will come at a more negative offset. */
8130 vid->index = size_binop (MINUS_EXPR, vid->index,
8131 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8133 /* The initializer is the delta from BINFO to this virtual base.
8134 The vbase offsets go in reverse inheritance-graph order, and
8135 we are walking in inheritance graph order so these end up in
8137 delta = size_diffop_loc (input_location,
8138 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
8140 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE,
8141 fold_build1_loc (input_location, NOP_EXPR,
8142 vtable_entry_type, delta));
8146 /* Adds the initializers for the vcall offset entries in the vtable
8147 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
8151 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8153 /* We only need these entries if this base is a virtual base. We
8154 compute the indices -- but do not add to the vtable -- when
8155 building the main vtable for a class. */
8156 if (binfo == TYPE_BINFO (vid->derived)
8157 || (BINFO_VIRTUAL_P (binfo)
8158 /* If BINFO is RTTI_BINFO, then (since BINFO does not
8159 correspond to VID->DERIVED), we are building a primary
8160 construction virtual table. Since this is a primary
8161 virtual table, we do not need the vcall offsets for
8163 && binfo != vid->rtti_binfo))
8165 /* We need a vcall offset for each of the virtual functions in this
8166 vtable. For example:
8168 class A { virtual void f (); };
8169 class B1 : virtual public A { virtual void f (); };
8170 class B2 : virtual public A { virtual void f (); };
8171 class C: public B1, public B2 { virtual void f (); };
8173 A C object has a primary base of B1, which has a primary base of A. A
8174 C also has a secondary base of B2, which no longer has a primary base
8175 of A. So the B2-in-C construction vtable needs a secondary vtable for
8176 A, which will adjust the A* to a B2* to call f. We have no way of
8177 knowing what (or even whether) this offset will be when we define B2,
8178 so we store this "vcall offset" in the A sub-vtable and look it up in
8179 a "virtual thunk" for B2::f.
8181 We need entries for all the functions in our primary vtable and
8182 in our non-virtual bases' secondary vtables. */
8184 /* If we are just computing the vcall indices -- but do not need
8185 the actual entries -- not that. */
8186 if (!BINFO_VIRTUAL_P (binfo))
8187 vid->generate_vcall_entries = false;
8188 /* Now, walk through the non-virtual bases, adding vcall offsets. */
8189 add_vcall_offset_vtbl_entries_r (binfo, vid);
8193 /* Build vcall offsets, starting with those for BINFO. */
8196 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
8202 /* Don't walk into virtual bases -- except, of course, for the
8203 virtual base for which we are building vcall offsets. Any
8204 primary virtual base will have already had its offsets generated
8205 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8206 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
8209 /* If BINFO has a primary base, process it first. */
8210 primary_binfo = get_primary_binfo (binfo);
8212 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
8214 /* Add BINFO itself to the list. */
8215 add_vcall_offset_vtbl_entries_1 (binfo, vid);
8217 /* Scan the non-primary bases of BINFO. */
8218 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8219 if (base_binfo != primary_binfo)
8220 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
8223 /* Called from build_vcall_offset_vtbl_entries_r. */
8226 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
8228 /* Make entries for the rest of the virtuals. */
8229 if (abi_version_at_least (2))
8233 /* The ABI requires that the methods be processed in declaration
8234 order. G++ 3.2 used the order in the vtable. */
8235 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
8237 orig_fn = DECL_CHAIN (orig_fn))
8238 if (DECL_VINDEX (orig_fn))
8239 add_vcall_offset (orig_fn, binfo, vid);
8243 tree derived_virtuals;
8246 /* If BINFO is a primary base, the most derived class which has
8247 BINFO as a primary base; otherwise, just BINFO. */
8248 tree non_primary_binfo;
8250 /* We might be a primary base class. Go up the inheritance hierarchy
8251 until we find the most derived class of which we are a primary base:
8252 it is the BINFO_VIRTUALS there that we need to consider. */
8253 non_primary_binfo = binfo;
8254 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8258 /* If we have reached a virtual base, then it must be vid->vbase,
8259 because we ignore other virtual bases in
8260 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8261 base (possibly multi-level) of vid->binfo, or we wouldn't
8262 have called build_vcall_and_vbase_vtbl_entries for it. But it
8263 might be a lost primary, so just skip down to vid->binfo. */
8264 if (BINFO_VIRTUAL_P (non_primary_binfo))
8266 gcc_assert (non_primary_binfo == vid->vbase);
8267 non_primary_binfo = vid->binfo;
8271 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8272 if (get_primary_binfo (b) != non_primary_binfo)
8274 non_primary_binfo = b;
8277 if (vid->ctor_vtbl_p)
8278 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8279 where rtti_binfo is the most derived type. */
8281 = original_binfo (non_primary_binfo, vid->rtti_binfo);
8283 for (base_virtuals = BINFO_VIRTUALS (binfo),
8284 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
8285 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
8287 base_virtuals = TREE_CHAIN (base_virtuals),
8288 derived_virtuals = TREE_CHAIN (derived_virtuals),
8289 orig_virtuals = TREE_CHAIN (orig_virtuals))
8293 /* Find the declaration that originally caused this function to
8294 be present in BINFO_TYPE (binfo). */
8295 orig_fn = BV_FN (orig_virtuals);
8297 /* When processing BINFO, we only want to generate vcall slots for
8298 function slots introduced in BINFO. So don't try to generate
8299 one if the function isn't even defined in BINFO. */
8300 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
8303 add_vcall_offset (orig_fn, binfo, vid);
8308 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8311 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
8317 /* If there is already an entry for a function with the same
8318 signature as FN, then we do not need a second vcall offset.
8319 Check the list of functions already present in the derived
8321 FOR_EACH_VEC_ELT (tree, vid->fns, i, derived_entry)
8323 if (same_signature_p (derived_entry, orig_fn)
8324 /* We only use one vcall offset for virtual destructors,
8325 even though there are two virtual table entries. */
8326 || (DECL_DESTRUCTOR_P (derived_entry)
8327 && DECL_DESTRUCTOR_P (orig_fn)))
8331 /* If we are building these vcall offsets as part of building
8332 the vtable for the most derived class, remember the vcall
8334 if (vid->binfo == TYPE_BINFO (vid->derived))
8336 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
8337 CLASSTYPE_VCALL_INDICES (vid->derived),
8339 elt->purpose = orig_fn;
8340 elt->value = vid->index;
8343 /* The next vcall offset will be found at a more negative
8345 vid->index = size_binop (MINUS_EXPR, vid->index,
8346 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8348 /* Keep track of this function. */
8349 VEC_safe_push (tree, gc, vid->fns, orig_fn);
8351 if (vid->generate_vcall_entries)
8356 /* Find the overriding function. */
8357 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8358 if (fn == error_mark_node)
8359 vcall_offset = build_zero_cst (vtable_entry_type);
8362 base = TREE_VALUE (fn);
8364 /* The vbase we're working on is a primary base of
8365 vid->binfo. But it might be a lost primary, so its
8366 BINFO_OFFSET might be wrong, so we just use the
8367 BINFO_OFFSET from vid->binfo. */
8368 vcall_offset = size_diffop_loc (input_location,
8369 BINFO_OFFSET (base),
8370 BINFO_OFFSET (vid->binfo));
8371 vcall_offset = fold_build1_loc (input_location,
8372 NOP_EXPR, vtable_entry_type,
8375 /* Add the initializer to the vtable. */
8376 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, vcall_offset);
8380 /* Return vtbl initializers for the RTTI entries corresponding to the
8381 BINFO's vtable. The RTTI entries should indicate the object given
8382 by VID->rtti_binfo. */
8385 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8393 t = BINFO_TYPE (vid->rtti_binfo);
8395 /* To find the complete object, we will first convert to our most
8396 primary base, and then add the offset in the vtbl to that value. */
8398 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8399 && !BINFO_LOST_PRIMARY_P (b))
8403 primary_base = get_primary_binfo (b);
8404 gcc_assert (BINFO_PRIMARY_P (primary_base)
8405 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8408 offset = size_diffop_loc (input_location,
8409 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8411 /* The second entry is the address of the typeinfo object. */
8413 decl = build_address (get_tinfo_decl (t));
8415 decl = integer_zero_node;
8417 /* Convert the declaration to a type that can be stored in the
8419 init = build_nop (vfunc_ptr_type_node, decl);
8420 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8422 /* Add the offset-to-top entry. It comes earlier in the vtable than
8423 the typeinfo entry. Convert the offset to look like a
8424 function pointer, so that we can put it in the vtable. */
8425 init = build_nop (vfunc_ptr_type_node, offset);
8426 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8429 #include "gt-cp-class.h"