1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
38 #include "tree-dump.h"
39 #include "splay-tree.h"
40 #include "pointer-set.h"
42 /* The number of nested classes being processed. If we are not in the
43 scope of any class, this is zero. */
45 int current_class_depth;
47 /* In order to deal with nested classes, we keep a stack of classes.
48 The topmost entry is the innermost class, and is the entry at index
49 CURRENT_CLASS_DEPTH */
51 typedef struct class_stack_node {
52 /* The name of the class. */
55 /* The _TYPE node for the class. */
58 /* The access specifier pending for new declarations in the scope of
62 /* If were defining TYPE, the names used in this class. */
63 splay_tree names_used;
65 /* Nonzero if this class is no longer open, because of a call to
68 }* class_stack_node_t;
70 typedef struct vtbl_init_data_s
72 /* The base for which we're building initializers. */
74 /* The type of the most-derived type. */
76 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
77 unless ctor_vtbl_p is true. */
79 /* The negative-index vtable initializers built up so far. These
80 are in order from least negative index to most negative index. */
81 VEC(constructor_elt,gc) *inits;
82 /* The binfo for the virtual base for which we're building
83 vcall offset initializers. */
85 /* The functions in vbase for which we have already provided vcall
88 /* The vtable index of the next vcall or vbase offset. */
90 /* Nonzero if we are building the initializer for the primary
93 /* Nonzero if we are building the initializer for a construction
96 /* True when adding vcall offset entries to the vtable. False when
97 merely computing the indices. */
98 bool generate_vcall_entries;
101 /* The type of a function passed to walk_subobject_offsets. */
102 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
104 /* The stack itself. This is a dynamically resized array. The
105 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
106 static int current_class_stack_size;
107 static class_stack_node_t current_class_stack;
109 /* The size of the largest empty class seen in this translation unit. */
110 static GTY (()) tree sizeof_biggest_empty_class;
112 /* An array of all local classes present in this translation unit, in
113 declaration order. */
114 VEC(tree,gc) *local_classes;
116 static tree get_vfield_name (tree);
117 static void finish_struct_anon (tree);
118 static tree get_vtable_name (tree);
119 static tree get_basefndecls (tree, tree);
120 static int build_primary_vtable (tree, tree);
121 static int build_secondary_vtable (tree);
122 static void finish_vtbls (tree);
123 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
124 static void finish_struct_bits (tree);
125 static int alter_access (tree, tree, tree);
126 static void handle_using_decl (tree, tree);
127 static tree dfs_modify_vtables (tree, void *);
128 static tree modify_all_vtables (tree, tree);
129 static void determine_primary_bases (tree);
130 static void finish_struct_methods (tree);
131 static void maybe_warn_about_overly_private_class (tree);
132 static int method_name_cmp (const void *, const void *);
133 static int resort_method_name_cmp (const void *, const void *);
134 static void add_implicitly_declared_members (tree, int, int);
135 static tree fixed_type_or_null (tree, int *, int *);
136 static tree build_simple_base_path (tree expr, tree binfo);
137 static tree build_vtbl_ref_1 (tree, tree);
138 static void build_vtbl_initializer (tree, tree, tree, tree, int *,
139 VEC(constructor_elt,gc) **);
140 static int count_fields (tree);
141 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
142 static bool check_bitfield_decl (tree);
143 static void check_field_decl (tree, tree, int *, int *, int *);
144 static void check_field_decls (tree, tree *, int *, int *);
145 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
146 static void build_base_fields (record_layout_info, splay_tree, tree *);
147 static void check_methods (tree);
148 static void remove_zero_width_bit_fields (tree);
149 static void check_bases (tree, int *, int *);
150 static void check_bases_and_members (tree);
151 static tree create_vtable_ptr (tree, tree *);
152 static void include_empty_classes (record_layout_info);
153 static void layout_class_type (tree, tree *);
154 static void propagate_binfo_offsets (tree, tree);
155 static void layout_virtual_bases (record_layout_info, splay_tree);
156 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
157 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
158 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
159 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
160 static void add_vcall_offset (tree, tree, vtbl_init_data *);
161 static void layout_vtable_decl (tree, int);
162 static tree dfs_find_final_overrider_pre (tree, void *);
163 static tree dfs_find_final_overrider_post (tree, void *);
164 static tree find_final_overrider (tree, tree, tree);
165 static int make_new_vtable (tree, tree);
166 static tree get_primary_binfo (tree);
167 static int maybe_indent_hierarchy (FILE *, int, int);
168 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
169 static void dump_class_hierarchy (tree);
170 static void dump_class_hierarchy_1 (FILE *, int, tree);
171 static void dump_array (FILE *, tree);
172 static void dump_vtable (tree, tree, tree);
173 static void dump_vtt (tree, tree);
174 static void dump_thunk (FILE *, int, tree);
175 static tree build_vtable (tree, tree, tree);
176 static void initialize_vtable (tree, VEC(constructor_elt,gc) *);
177 static void layout_nonempty_base_or_field (record_layout_info,
178 tree, tree, splay_tree);
179 static tree end_of_class (tree, int);
180 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
181 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree,
182 VEC(constructor_elt,gc) **);
183 static void dfs_accumulate_vtbl_inits (tree, tree, tree, tree, tree,
184 VEC(constructor_elt,gc) **);
185 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
186 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
187 static void clone_constructors_and_destructors (tree);
188 static tree build_clone (tree, tree);
189 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
190 static void build_ctor_vtbl_group (tree, tree);
191 static void build_vtt (tree);
192 static tree binfo_ctor_vtable (tree);
193 static void build_vtt_inits (tree, tree, VEC(constructor_elt,gc) **, tree *);
194 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
195 static tree dfs_fixup_binfo_vtbls (tree, void *);
196 static int record_subobject_offset (tree, tree, splay_tree);
197 static int check_subobject_offset (tree, tree, splay_tree);
198 static int walk_subobject_offsets (tree, subobject_offset_fn,
199 tree, splay_tree, tree, int);
200 static void record_subobject_offsets (tree, tree, splay_tree, bool);
201 static int layout_conflict_p (tree, tree, splay_tree, int);
202 static int splay_tree_compare_integer_csts (splay_tree_key k1,
204 static void warn_about_ambiguous_bases (tree);
205 static bool type_requires_array_cookie (tree);
206 static bool contains_empty_class_p (tree);
207 static bool base_derived_from (tree, tree);
208 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
209 static tree end_of_base (tree);
210 static tree get_vcall_index (tree, tree);
212 /* Variables shared between class.c and call.c. */
214 #ifdef GATHER_STATISTICS
216 int n_vtable_entries = 0;
217 int n_vtable_searches = 0;
218 int n_vtable_elems = 0;
219 int n_convert_harshness = 0;
220 int n_compute_conversion_costs = 0;
221 int n_inner_fields_searched = 0;
224 /* Convert to or from a base subobject. EXPR is an expression of type
225 `A' or `A*', an expression of type `B' or `B*' is returned. To
226 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
227 the B base instance within A. To convert base A to derived B, CODE
228 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
229 In this latter case, A must not be a morally virtual base of B.
230 NONNULL is true if EXPR is known to be non-NULL (this is only
231 needed when EXPR is of pointer type). CV qualifiers are preserved
235 build_base_path (enum tree_code code,
239 tsubst_flags_t complain)
241 tree v_binfo = NULL_TREE;
242 tree d_binfo = NULL_TREE;
246 tree null_test = NULL;
247 tree ptr_target_type;
249 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
250 bool has_empty = false;
253 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
254 return error_mark_node;
256 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
259 if (is_empty_class (BINFO_TYPE (probe)))
261 if (!v_binfo && BINFO_VIRTUAL_P (probe))
265 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
267 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
269 gcc_assert ((code == MINUS_EXPR
270 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
271 || (code == PLUS_EXPR
272 && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
274 if (binfo == d_binfo)
278 if (code == MINUS_EXPR && v_binfo)
280 if (complain & tf_error)
281 error ("cannot convert from base %qT to derived type %qT via "
282 "virtual base %qT", BINFO_TYPE (binfo), BINFO_TYPE (d_binfo),
283 BINFO_TYPE (v_binfo));
284 return error_mark_node;
288 /* This must happen before the call to save_expr. */
289 expr = cp_build_addr_expr (expr, complain);
291 expr = mark_rvalue_use (expr);
293 offset = BINFO_OFFSET (binfo);
294 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
295 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
296 /* TARGET_TYPE has been extracted from BINFO, and, is therefore always
297 cv-unqualified. Extract the cv-qualifiers from EXPR so that the
298 expression returned matches the input. */
299 target_type = cp_build_qualified_type
300 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
301 ptr_target_type = build_pointer_type (target_type);
303 /* Do we need to look in the vtable for the real offset? */
304 virtual_access = (v_binfo && fixed_type_p <= 0);
306 /* Don't bother with the calculations inside sizeof; they'll ICE if the
307 source type is incomplete and the pointer value doesn't matter. In a
308 template (even in fold_non_dependent_expr), we don't have vtables set
309 up properly yet, and the value doesn't matter there either; we're just
310 interested in the result of overload resolution. */
311 if (cp_unevaluated_operand != 0
312 || (current_function_decl
313 && uses_template_parms (current_function_decl)))
315 expr = build_nop (ptr_target_type, expr);
317 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
321 /* If we're in an NSDMI, we don't have the full constructor context yet
322 that we need for converting to a virtual base, so just build a stub
323 CONVERT_EXPR and expand it later in bot_replace. */
324 if (virtual_access && fixed_type_p < 0
325 && current_scope () != current_function_decl)
327 expr = build1 (CONVERT_EXPR, ptr_target_type, expr);
328 CONVERT_EXPR_VBASE_PATH (expr) = true;
330 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
334 /* Do we need to check for a null pointer? */
335 if (want_pointer && !nonnull)
337 /* If we know the conversion will not actually change the value
338 of EXPR, then we can avoid testing the expression for NULL.
339 We have to avoid generating a COMPONENT_REF for a base class
340 field, because other parts of the compiler know that such
341 expressions are always non-NULL. */
342 if (!virtual_access && integer_zerop (offset))
343 return build_nop (ptr_target_type, expr);
344 null_test = error_mark_node;
347 /* Protect against multiple evaluation if necessary. */
348 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
349 expr = save_expr (expr);
351 /* Now that we've saved expr, build the real null test. */
354 tree zero = cp_convert (TREE_TYPE (expr), nullptr_node);
355 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
359 /* If this is a simple base reference, express it as a COMPONENT_REF. */
360 if (code == PLUS_EXPR && !virtual_access
361 /* We don't build base fields for empty bases, and they aren't very
362 interesting to the optimizers anyway. */
365 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
366 expr = build_simple_base_path (expr, binfo);
368 expr = build_address (expr);
369 target_type = TREE_TYPE (expr);
375 /* Going via virtual base V_BINFO. We need the static offset
376 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
377 V_BINFO. That offset is an entry in D_BINFO's vtable. */
380 if (fixed_type_p < 0 && in_base_initializer)
382 /* In a base member initializer, we cannot rely on the
383 vtable being set up. We have to indirect via the
387 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
388 t = build_pointer_type (t);
389 v_offset = convert (t, current_vtt_parm);
390 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
393 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, RO_NULL,
395 TREE_TYPE (TREE_TYPE (expr)));
397 v_offset = fold_build_pointer_plus (v_offset, BINFO_VPTR_FIELD (v_binfo));
398 v_offset = build1 (NOP_EXPR,
399 build_pointer_type (ptrdiff_type_node),
401 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
402 TREE_CONSTANT (v_offset) = 1;
404 offset = convert_to_integer (ptrdiff_type_node,
405 size_diffop_loc (input_location, offset,
406 BINFO_OFFSET (v_binfo)));
408 if (!integer_zerop (offset))
409 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
411 if (fixed_type_p < 0)
412 /* Negative fixed_type_p means this is a constructor or destructor;
413 virtual base layout is fixed in in-charge [cd]tors, but not in
415 offset = build3 (COND_EXPR, ptrdiff_type_node,
416 build2 (EQ_EXPR, boolean_type_node,
417 current_in_charge_parm, integer_zero_node),
419 convert_to_integer (ptrdiff_type_node,
420 BINFO_OFFSET (binfo)));
426 target_type = ptr_target_type;
428 expr = build1 (NOP_EXPR, ptr_target_type, expr);
430 if (!integer_zerop (offset))
432 offset = fold_convert (sizetype, offset);
433 if (code == MINUS_EXPR)
434 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
435 expr = fold_build_pointer_plus (expr, offset);
441 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
445 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
446 build_zero_cst (target_type));
451 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
452 Perform a derived-to-base conversion by recursively building up a
453 sequence of COMPONENT_REFs to the appropriate base fields. */
456 build_simple_base_path (tree expr, tree binfo)
458 tree type = BINFO_TYPE (binfo);
459 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
462 if (d_binfo == NULL_TREE)
466 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
468 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
469 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
470 an lvalue in the front end; only _DECLs and _REFs are lvalues
472 temp = unary_complex_lvalue (ADDR_EXPR, expr);
474 expr = cp_build_indirect_ref (temp, RO_NULL, tf_warning_or_error);
480 expr = build_simple_base_path (expr, d_binfo);
482 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
483 field; field = DECL_CHAIN (field))
484 /* Is this the base field created by build_base_field? */
485 if (TREE_CODE (field) == FIELD_DECL
486 && DECL_FIELD_IS_BASE (field)
487 && TREE_TYPE (field) == type
488 /* If we're looking for a field in the most-derived class,
489 also check the field offset; we can have two base fields
490 of the same type if one is an indirect virtual base and one
491 is a direct non-virtual base. */
492 && (BINFO_INHERITANCE_CHAIN (d_binfo)
493 || tree_int_cst_equal (byte_position (field),
494 BINFO_OFFSET (binfo))))
496 /* We don't use build_class_member_access_expr here, as that
497 has unnecessary checks, and more importantly results in
498 recursive calls to dfs_walk_once. */
499 int type_quals = cp_type_quals (TREE_TYPE (expr));
501 expr = build3 (COMPONENT_REF,
502 cp_build_qualified_type (type, type_quals),
503 expr, field, NULL_TREE);
504 expr = fold_if_not_in_template (expr);
506 /* Mark the expression const or volatile, as appropriate.
507 Even though we've dealt with the type above, we still have
508 to mark the expression itself. */
509 if (type_quals & TYPE_QUAL_CONST)
510 TREE_READONLY (expr) = 1;
511 if (type_quals & TYPE_QUAL_VOLATILE)
512 TREE_THIS_VOLATILE (expr) = 1;
517 /* Didn't find the base field?!? */
521 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
522 type is a class type or a pointer to a class type. In the former
523 case, TYPE is also a class type; in the latter it is another
524 pointer type. If CHECK_ACCESS is true, an error message is emitted
525 if TYPE is inaccessible. If OBJECT has pointer type, the value is
526 assumed to be non-NULL. */
529 convert_to_base (tree object, tree type, bool check_access, bool nonnull,
530 tsubst_flags_t complain)
536 if (TYPE_PTR_P (TREE_TYPE (object)))
538 object_type = TREE_TYPE (TREE_TYPE (object));
539 type = TREE_TYPE (type);
542 object_type = TREE_TYPE (object);
544 access = check_access ? ba_check : ba_unique;
545 if (!(complain & tf_error))
547 binfo = lookup_base (object_type, type,
550 if (!binfo || binfo == error_mark_node)
551 return error_mark_node;
553 return build_base_path (PLUS_EXPR, object, binfo, nonnull, complain);
556 /* EXPR is an expression with unqualified class type. BASE is a base
557 binfo of that class type. Returns EXPR, converted to the BASE
558 type. This function assumes that EXPR is the most derived class;
559 therefore virtual bases can be found at their static offsets. */
562 convert_to_base_statically (tree expr, tree base)
566 expr_type = TREE_TYPE (expr);
567 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
569 /* If this is a non-empty base, use a COMPONENT_REF. */
570 if (!is_empty_class (BINFO_TYPE (base)))
571 return build_simple_base_path (expr, base);
573 /* We use fold_build2 and fold_convert below to simplify the trees
574 provided to the optimizers. It is not safe to call these functions
575 when processing a template because they do not handle C++-specific
577 gcc_assert (!processing_template_decl);
578 expr = cp_build_addr_expr (expr, tf_warning_or_error);
579 if (!integer_zerop (BINFO_OFFSET (base)))
580 expr = fold_build_pointer_plus_loc (input_location,
581 expr, BINFO_OFFSET (base));
582 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
583 expr = build_fold_indirect_ref_loc (input_location, expr);
591 build_vfield_ref (tree datum, tree type)
593 tree vfield, vcontext;
595 if (datum == error_mark_node)
596 return error_mark_node;
598 /* First, convert to the requested type. */
599 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
600 datum = convert_to_base (datum, type, /*check_access=*/false,
601 /*nonnull=*/true, tf_warning_or_error);
603 /* Second, the requested type may not be the owner of its own vptr.
604 If not, convert to the base class that owns it. We cannot use
605 convert_to_base here, because VCONTEXT may appear more than once
606 in the inheritance hierarchy of TYPE, and thus direct conversion
607 between the types may be ambiguous. Following the path back up
608 one step at a time via primary bases avoids the problem. */
609 vfield = TYPE_VFIELD (type);
610 vcontext = DECL_CONTEXT (vfield);
611 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
613 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
614 type = TREE_TYPE (datum);
617 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
620 /* Given an object INSTANCE, return an expression which yields the
621 vtable element corresponding to INDEX. There are many special
622 cases for INSTANCE which we take care of here, mainly to avoid
623 creating extra tree nodes when we don't have to. */
626 build_vtbl_ref_1 (tree instance, tree idx)
629 tree vtbl = NULL_TREE;
631 /* Try to figure out what a reference refers to, and
632 access its virtual function table directly. */
635 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
637 tree basetype = non_reference (TREE_TYPE (instance));
639 if (fixed_type && !cdtorp)
641 tree binfo = lookup_base (fixed_type, basetype,
642 ba_unique | ba_quiet, NULL);
644 vtbl = unshare_expr (BINFO_VTABLE (binfo));
648 vtbl = build_vfield_ref (instance, basetype);
650 aref = build_array_ref (input_location, vtbl, idx);
651 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
657 build_vtbl_ref (tree instance, tree idx)
659 tree aref = build_vtbl_ref_1 (instance, idx);
664 /* Given a stable object pointer INSTANCE_PTR, return an expression which
665 yields a function pointer corresponding to vtable element INDEX. */
668 build_vfn_ref (tree instance_ptr, tree idx)
672 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, RO_NULL,
673 tf_warning_or_error),
676 /* When using function descriptors, the address of the
677 vtable entry is treated as a function pointer. */
678 if (TARGET_VTABLE_USES_DESCRIPTORS)
679 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
680 cp_build_addr_expr (aref, tf_warning_or_error));
682 /* Remember this as a method reference, for later devirtualization. */
683 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
688 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
689 for the given TYPE. */
692 get_vtable_name (tree type)
694 return mangle_vtbl_for_type (type);
697 /* DECL is an entity associated with TYPE, like a virtual table or an
698 implicitly generated constructor. Determine whether or not DECL
699 should have external or internal linkage at the object file
700 level. This routine does not deal with COMDAT linkage and other
701 similar complexities; it simply sets TREE_PUBLIC if it possible for
702 entities in other translation units to contain copies of DECL, in
706 set_linkage_according_to_type (tree type ATTRIBUTE_UNUSED, tree decl)
708 TREE_PUBLIC (decl) = 1;
709 determine_visibility (decl);
712 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
713 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
714 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
717 build_vtable (tree class_type, tree name, tree vtable_type)
721 decl = build_lang_decl (VAR_DECL, name, vtable_type);
722 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
723 now to avoid confusion in mangle_decl. */
724 SET_DECL_ASSEMBLER_NAME (decl, name);
725 DECL_CONTEXT (decl) = class_type;
726 DECL_ARTIFICIAL (decl) = 1;
727 TREE_STATIC (decl) = 1;
728 TREE_READONLY (decl) = 1;
729 DECL_VIRTUAL_P (decl) = 1;
730 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
731 DECL_VTABLE_OR_VTT_P (decl) = 1;
732 /* At one time the vtable info was grabbed 2 words at a time. This
733 fails on sparc unless you have 8-byte alignment. (tiemann) */
734 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
736 set_linkage_according_to_type (class_type, decl);
737 /* The vtable has not been defined -- yet. */
738 DECL_EXTERNAL (decl) = 1;
739 DECL_NOT_REALLY_EXTERN (decl) = 1;
741 /* Mark the VAR_DECL node representing the vtable itself as a
742 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
743 is rather important that such things be ignored because any
744 effort to actually generate DWARF for them will run into
745 trouble when/if we encounter code like:
748 struct S { virtual void member (); };
750 because the artificial declaration of the vtable itself (as
751 manufactured by the g++ front end) will say that the vtable is
752 a static member of `S' but only *after* the debug output for
753 the definition of `S' has already been output. This causes
754 grief because the DWARF entry for the definition of the vtable
755 will try to refer back to an earlier *declaration* of the
756 vtable as a static member of `S' and there won't be one. We
757 might be able to arrange to have the "vtable static member"
758 attached to the member list for `S' before the debug info for
759 `S' get written (which would solve the problem) but that would
760 require more intrusive changes to the g++ front end. */
761 DECL_IGNORED_P (decl) = 1;
766 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
767 or even complete. If this does not exist, create it. If COMPLETE is
768 nonzero, then complete the definition of it -- that will render it
769 impossible to actually build the vtable, but is useful to get at those
770 which are known to exist in the runtime. */
773 get_vtable_decl (tree type, int complete)
777 if (CLASSTYPE_VTABLES (type))
778 return CLASSTYPE_VTABLES (type);
780 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
781 CLASSTYPE_VTABLES (type) = decl;
785 DECL_EXTERNAL (decl) = 1;
786 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
792 /* Build the primary virtual function table for TYPE. If BINFO is
793 non-NULL, build the vtable starting with the initial approximation
794 that it is the same as the one which is the head of the association
795 list. Returns a nonzero value if a new vtable is actually
799 build_primary_vtable (tree binfo, tree type)
804 decl = get_vtable_decl (type, /*complete=*/0);
808 if (BINFO_NEW_VTABLE_MARKED (binfo))
809 /* We have already created a vtable for this base, so there's
810 no need to do it again. */
813 virtuals = copy_list (BINFO_VIRTUALS (binfo));
814 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
815 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
816 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
820 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
821 virtuals = NULL_TREE;
824 #ifdef GATHER_STATISTICS
826 n_vtable_elems += list_length (virtuals);
829 /* Initialize the association list for this type, based
830 on our first approximation. */
831 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
832 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
833 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
837 /* Give BINFO a new virtual function table which is initialized
838 with a skeleton-copy of its original initialization. The only
839 entry that changes is the `delta' entry, so we can really
840 share a lot of structure.
842 FOR_TYPE is the most derived type which caused this table to
845 Returns nonzero if we haven't met BINFO before.
847 The order in which vtables are built (by calling this function) for
848 an object must remain the same, otherwise a binary incompatibility
852 build_secondary_vtable (tree binfo)
854 if (BINFO_NEW_VTABLE_MARKED (binfo))
855 /* We already created a vtable for this base. There's no need to
859 /* Remember that we've created a vtable for this BINFO, so that we
860 don't try to do so again. */
861 SET_BINFO_NEW_VTABLE_MARKED (binfo);
863 /* Make fresh virtual list, so we can smash it later. */
864 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
866 /* Secondary vtables are laid out as part of the same structure as
867 the primary vtable. */
868 BINFO_VTABLE (binfo) = NULL_TREE;
872 /* Create a new vtable for BINFO which is the hierarchy dominated by
873 T. Return nonzero if we actually created a new vtable. */
876 make_new_vtable (tree t, tree binfo)
878 if (binfo == TYPE_BINFO (t))
879 /* In this case, it is *type*'s vtable we are modifying. We start
880 with the approximation that its vtable is that of the
881 immediate base class. */
882 return build_primary_vtable (binfo, t);
884 /* This is our very own copy of `basetype' to play with. Later,
885 we will fill in all the virtual functions that override the
886 virtual functions in these base classes which are not defined
887 by the current type. */
888 return build_secondary_vtable (binfo);
891 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
892 (which is in the hierarchy dominated by T) list FNDECL as its
893 BV_FN. DELTA is the required constant adjustment from the `this'
894 pointer where the vtable entry appears to the `this' required when
895 the function is actually called. */
898 modify_vtable_entry (tree t,
908 if (fndecl != BV_FN (v)
909 || !tree_int_cst_equal (delta, BV_DELTA (v)))
911 /* We need a new vtable for BINFO. */
912 if (make_new_vtable (t, binfo))
914 /* If we really did make a new vtable, we also made a copy
915 of the BINFO_VIRTUALS list. Now, we have to find the
916 corresponding entry in that list. */
917 *virtuals = BINFO_VIRTUALS (binfo);
918 while (BV_FN (*virtuals) != BV_FN (v))
919 *virtuals = TREE_CHAIN (*virtuals);
923 BV_DELTA (v) = delta;
924 BV_VCALL_INDEX (v) = NULL_TREE;
930 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
931 the USING_DECL naming METHOD. Returns true if the method could be
932 added to the method vec. */
935 add_method (tree type, tree method, tree using_decl)
939 bool template_conv_p = false;
941 VEC(tree,gc) *method_vec;
943 bool insert_p = false;
947 if (method == error_mark_node)
950 complete_p = COMPLETE_TYPE_P (type);
951 conv_p = DECL_CONV_FN_P (method);
953 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
954 && DECL_TEMPLATE_CONV_FN_P (method));
956 method_vec = CLASSTYPE_METHOD_VEC (type);
959 /* Make a new method vector. We start with 8 entries. We must
960 allocate at least two (for constructors and destructors), and
961 we're going to end up with an assignment operator at some
963 method_vec = VEC_alloc (tree, gc, 8);
964 /* Create slots for constructors and destructors. */
965 VEC_quick_push (tree, method_vec, NULL_TREE);
966 VEC_quick_push (tree, method_vec, NULL_TREE);
967 CLASSTYPE_METHOD_VEC (type) = method_vec;
970 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
971 grok_special_member_properties (method);
973 /* Constructors and destructors go in special slots. */
974 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
975 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
976 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
978 slot = CLASSTYPE_DESTRUCTOR_SLOT;
980 if (TYPE_FOR_JAVA (type))
982 if (!DECL_ARTIFICIAL (method))
983 error ("Java class %qT cannot have a destructor", type);
984 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
985 error ("Java class %qT cannot have an implicit non-trivial "
995 /* See if we already have an entry with this name. */
996 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
997 VEC_iterate (tree, method_vec, slot, m);
1000 m = OVL_CURRENT (m);
1001 if (template_conv_p)
1003 if (TREE_CODE (m) == TEMPLATE_DECL
1004 && DECL_TEMPLATE_CONV_FN_P (m))
1008 if (conv_p && !DECL_CONV_FN_P (m))
1010 if (DECL_NAME (m) == DECL_NAME (method))
1016 && !DECL_CONV_FN_P (m)
1017 && DECL_NAME (m) > DECL_NAME (method))
1021 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1023 /* Check to see if we've already got this method. */
1024 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1026 tree fn = OVL_CURRENT (fns);
1032 if (TREE_CODE (fn) != TREE_CODE (method))
1035 /* [over.load] Member function declarations with the
1036 same name and the same parameter types cannot be
1037 overloaded if any of them is a static member
1038 function declaration.
1040 [namespace.udecl] When a using-declaration brings names
1041 from a base class into a derived class scope, member
1042 functions in the derived class override and/or hide member
1043 functions with the same name and parameter types in a base
1044 class (rather than conflicting). */
1045 fn_type = TREE_TYPE (fn);
1046 method_type = TREE_TYPE (method);
1047 parms1 = TYPE_ARG_TYPES (fn_type);
1048 parms2 = TYPE_ARG_TYPES (method_type);
1050 /* Compare the quals on the 'this' parm. Don't compare
1051 the whole types, as used functions are treated as
1052 coming from the using class in overload resolution. */
1053 if (! DECL_STATIC_FUNCTION_P (fn)
1054 && ! DECL_STATIC_FUNCTION_P (method)
1055 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1056 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1057 && (cp_type_quals (TREE_TYPE (TREE_VALUE (parms1)))
1058 != cp_type_quals (TREE_TYPE (TREE_VALUE (parms2)))))
1061 /* For templates, the return type and template parameters
1062 must be identical. */
1063 if (TREE_CODE (fn) == TEMPLATE_DECL
1064 && (!same_type_p (TREE_TYPE (fn_type),
1065 TREE_TYPE (method_type))
1066 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1067 DECL_TEMPLATE_PARMS (method))))
1070 if (! DECL_STATIC_FUNCTION_P (fn))
1071 parms1 = TREE_CHAIN (parms1);
1072 if (! DECL_STATIC_FUNCTION_P (method))
1073 parms2 = TREE_CHAIN (parms2);
1075 if (compparms (parms1, parms2)
1076 && (!DECL_CONV_FN_P (fn)
1077 || same_type_p (TREE_TYPE (fn_type),
1078 TREE_TYPE (method_type))))
1082 if (DECL_CONTEXT (fn) == type)
1083 /* Defer to the local function. */
1088 error ("%q+#D cannot be overloaded", method);
1089 error ("with %q+#D", fn);
1092 /* We don't call duplicate_decls here to merge the
1093 declarations because that will confuse things if the
1094 methods have inline definitions. In particular, we
1095 will crash while processing the definitions. */
1100 /* A class should never have more than one destructor. */
1101 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1104 /* Add the new binding. */
1105 overload = build_overload (method, current_fns);
1108 TYPE_HAS_CONVERSION (type) = 1;
1109 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1110 push_class_level_binding (DECL_NAME (method), overload);
1116 /* We only expect to add few methods in the COMPLETE_P case, so
1117 just make room for one more method in that case. */
1119 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1121 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1123 CLASSTYPE_METHOD_VEC (type) = method_vec;
1124 if (slot == VEC_length (tree, method_vec))
1125 VEC_quick_push (tree, method_vec, overload);
1127 VEC_quick_insert (tree, method_vec, slot, overload);
1130 /* Replace the current slot. */
1131 VEC_replace (tree, method_vec, slot, overload);
1135 /* Subroutines of finish_struct. */
1137 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1138 legit, otherwise return 0. */
1141 alter_access (tree t, tree fdecl, tree access)
1145 if (!DECL_LANG_SPECIFIC (fdecl))
1146 retrofit_lang_decl (fdecl);
1148 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1150 elem = purpose_member (t, DECL_ACCESS (fdecl));
1153 if (TREE_VALUE (elem) != access)
1155 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1156 error ("conflicting access specifications for method"
1157 " %q+D, ignored", TREE_TYPE (fdecl));
1159 error ("conflicting access specifications for field %qE, ignored",
1164 /* They're changing the access to the same thing they changed
1165 it to before. That's OK. */
1171 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1172 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1178 /* Process the USING_DECL, which is a member of T. */
1181 handle_using_decl (tree using_decl, tree t)
1183 tree decl = USING_DECL_DECLS (using_decl);
1184 tree name = DECL_NAME (using_decl);
1186 = TREE_PRIVATE (using_decl) ? access_private_node
1187 : TREE_PROTECTED (using_decl) ? access_protected_node
1188 : access_public_node;
1189 tree flist = NULL_TREE;
1192 gcc_assert (!processing_template_decl && decl);
1194 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false,
1195 tf_warning_or_error);
1198 if (is_overloaded_fn (old_value))
1199 old_value = OVL_CURRENT (old_value);
1201 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1204 old_value = NULL_TREE;
1207 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1209 if (is_overloaded_fn (decl))
1214 else if (is_overloaded_fn (old_value))
1217 /* It's OK to use functions from a base when there are functions with
1218 the same name already present in the current class. */;
1221 error ("%q+D invalid in %q#T", using_decl, t);
1222 error (" because of local method %q+#D with same name",
1223 OVL_CURRENT (old_value));
1227 else if (!DECL_ARTIFICIAL (old_value))
1229 error ("%q+D invalid in %q#T", using_decl, t);
1230 error (" because of local member %q+#D with same name", old_value);
1234 /* Make type T see field decl FDECL with access ACCESS. */
1236 for (; flist; flist = OVL_NEXT (flist))
1238 add_method (t, OVL_CURRENT (flist), using_decl);
1239 alter_access (t, OVL_CURRENT (flist), access);
1242 alter_access (t, decl, access);
1245 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1246 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1247 properties of the bases. */
1250 check_bases (tree t,
1251 int* cant_have_const_ctor_p,
1252 int* no_const_asn_ref_p)
1255 bool seen_non_virtual_nearly_empty_base_p = 0;
1256 int seen_tm_mask = 0;
1259 tree field = NULL_TREE;
1261 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1262 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
1263 if (TREE_CODE (field) == FIELD_DECL)
1266 for (binfo = TYPE_BINFO (t), i = 0;
1267 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1269 tree basetype = TREE_TYPE (base_binfo);
1271 gcc_assert (COMPLETE_TYPE_P (basetype));
1273 if (CLASSTYPE_FINAL (basetype))
1274 error ("cannot derive from %<final%> base %qT in derived type %qT",
1277 /* If any base class is non-literal, so is the derived class. */
1278 if (!CLASSTYPE_LITERAL_P (basetype))
1279 CLASSTYPE_LITERAL_P (t) = false;
1281 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1282 here because the case of virtual functions but non-virtual
1283 dtor is handled in finish_struct_1. */
1284 if (!TYPE_POLYMORPHIC_P (basetype))
1285 warning (OPT_Weffc__,
1286 "base class %q#T has a non-virtual destructor", basetype);
1288 /* If the base class doesn't have copy constructors or
1289 assignment operators that take const references, then the
1290 derived class cannot have such a member automatically
1292 if (TYPE_HAS_COPY_CTOR (basetype)
1293 && ! TYPE_HAS_CONST_COPY_CTOR (basetype))
1294 *cant_have_const_ctor_p = 1;
1295 if (TYPE_HAS_COPY_ASSIGN (basetype)
1296 && !TYPE_HAS_CONST_COPY_ASSIGN (basetype))
1297 *no_const_asn_ref_p = 1;
1299 if (BINFO_VIRTUAL_P (base_binfo))
1300 /* A virtual base does not effect nearly emptiness. */
1302 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1304 if (seen_non_virtual_nearly_empty_base_p)
1305 /* And if there is more than one nearly empty base, then the
1306 derived class is not nearly empty either. */
1307 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1309 /* Remember we've seen one. */
1310 seen_non_virtual_nearly_empty_base_p = 1;
1312 else if (!is_empty_class (basetype))
1313 /* If the base class is not empty or nearly empty, then this
1314 class cannot be nearly empty. */
1315 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1317 /* A lot of properties from the bases also apply to the derived
1319 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1320 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1321 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1322 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
1323 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (basetype)
1324 || !TYPE_HAS_COPY_ASSIGN (basetype));
1325 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (basetype)
1326 || !TYPE_HAS_COPY_CTOR (basetype));
1327 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t)
1328 |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (basetype);
1329 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (basetype);
1330 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1331 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1332 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1333 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
1334 || TYPE_HAS_COMPLEX_DFLT (basetype));
1336 /* A standard-layout class is a class that:
1338 * has no non-standard-layout base classes, */
1339 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1340 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1343 /* ...has no base classes of the same type as the first non-static
1345 if (field && DECL_CONTEXT (field) == t
1346 && (same_type_ignoring_top_level_qualifiers_p
1347 (TREE_TYPE (field), basetype)))
1348 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1350 /* ...either has no non-static data members in the most-derived
1351 class and at most one base class with non-static data
1352 members, or has no base classes with non-static data
1354 for (basefield = TYPE_FIELDS (basetype); basefield;
1355 basefield = DECL_CHAIN (basefield))
1356 if (TREE_CODE (basefield) == FIELD_DECL)
1359 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1366 /* Don't bother collecting tm attributes if transactional memory
1367 support is not enabled. */
1370 tree tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (basetype));
1372 seen_tm_mask |= tm_attr_to_mask (tm_attr);
1376 /* If one of the base classes had TM attributes, and the current class
1377 doesn't define its own, then the current class inherits one. */
1378 if (seen_tm_mask && !find_tm_attribute (TYPE_ATTRIBUTES (t)))
1380 tree tm_attr = tm_mask_to_attr (seen_tm_mask & -seen_tm_mask);
1381 TYPE_ATTRIBUTES (t) = tree_cons (tm_attr, NULL, TYPE_ATTRIBUTES (t));
1385 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1386 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1387 that have had a nearly-empty virtual primary base stolen by some
1388 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1392 determine_primary_bases (tree t)
1395 tree primary = NULL_TREE;
1396 tree type_binfo = TYPE_BINFO (t);
1399 /* Determine the primary bases of our bases. */
1400 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1401 base_binfo = TREE_CHAIN (base_binfo))
1403 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1405 /* See if we're the non-virtual primary of our inheritance
1407 if (!BINFO_VIRTUAL_P (base_binfo))
1409 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1410 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1413 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1414 BINFO_TYPE (parent_primary)))
1415 /* We are the primary binfo. */
1416 BINFO_PRIMARY_P (base_binfo) = 1;
1418 /* Determine if we have a virtual primary base, and mark it so.
1420 if (primary && BINFO_VIRTUAL_P (primary))
1422 tree this_primary = copied_binfo (primary, base_binfo);
1424 if (BINFO_PRIMARY_P (this_primary))
1425 /* Someone already claimed this base. */
1426 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1431 BINFO_PRIMARY_P (this_primary) = 1;
1432 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1434 /* A virtual binfo might have been copied from within
1435 another hierarchy. As we're about to use it as a
1436 primary base, make sure the offsets match. */
1437 delta = size_diffop_loc (input_location,
1439 BINFO_OFFSET (base_binfo)),
1441 BINFO_OFFSET (this_primary)));
1443 propagate_binfo_offsets (this_primary, delta);
1448 /* First look for a dynamic direct non-virtual base. */
1449 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1451 tree basetype = BINFO_TYPE (base_binfo);
1453 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1455 primary = base_binfo;
1460 /* A "nearly-empty" virtual base class can be the primary base
1461 class, if no non-virtual polymorphic base can be found. Look for
1462 a nearly-empty virtual dynamic base that is not already a primary
1463 base of something in the hierarchy. If there is no such base,
1464 just pick the first nearly-empty virtual base. */
1466 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1467 base_binfo = TREE_CHAIN (base_binfo))
1468 if (BINFO_VIRTUAL_P (base_binfo)
1469 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1471 if (!BINFO_PRIMARY_P (base_binfo))
1473 /* Found one that is not primary. */
1474 primary = base_binfo;
1478 /* Remember the first candidate. */
1479 primary = base_binfo;
1483 /* If we've got a primary base, use it. */
1486 tree basetype = BINFO_TYPE (primary);
1488 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1489 if (BINFO_PRIMARY_P (primary))
1490 /* We are stealing a primary base. */
1491 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1492 BINFO_PRIMARY_P (primary) = 1;
1493 if (BINFO_VIRTUAL_P (primary))
1497 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1498 /* A virtual binfo might have been copied from within
1499 another hierarchy. As we're about to use it as a primary
1500 base, make sure the offsets match. */
1501 delta = size_diffop_loc (input_location, ssize_int (0),
1502 convert (ssizetype, BINFO_OFFSET (primary)));
1504 propagate_binfo_offsets (primary, delta);
1507 primary = TYPE_BINFO (basetype);
1509 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1510 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1511 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1515 /* Update the variant types of T. */
1518 fixup_type_variants (tree t)
1525 for (variants = TYPE_NEXT_VARIANT (t);
1527 variants = TYPE_NEXT_VARIANT (variants))
1529 /* These fields are in the _TYPE part of the node, not in
1530 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1531 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1532 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1533 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1534 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1536 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1538 TYPE_BINFO (variants) = TYPE_BINFO (t);
1540 /* Copy whatever these are holding today. */
1541 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1542 TYPE_METHODS (variants) = TYPE_METHODS (t);
1543 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1547 /* Early variant fixups: we apply attributes at the beginning of the class
1548 definition, and we need to fix up any variants that have already been
1549 made via elaborated-type-specifier so that check_qualified_type works. */
1552 fixup_attribute_variants (tree t)
1559 for (variants = TYPE_NEXT_VARIANT (t);
1561 variants = TYPE_NEXT_VARIANT (variants))
1563 /* These are the two fields that check_qualified_type looks at and
1564 are affected by attributes. */
1565 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1566 TYPE_ALIGN (variants) = TYPE_ALIGN (t);
1570 /* Set memoizing fields and bits of T (and its variants) for later
1574 finish_struct_bits (tree t)
1576 /* Fix up variants (if any). */
1577 fixup_type_variants (t);
1579 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1580 /* For a class w/o baseclasses, 'finish_struct' has set
1581 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1582 Similarly for a class whose base classes do not have vtables.
1583 When neither of these is true, we might have removed abstract
1584 virtuals (by providing a definition), added some (by declaring
1585 new ones), or redeclared ones from a base class. We need to
1586 recalculate what's really an abstract virtual at this point (by
1587 looking in the vtables). */
1588 get_pure_virtuals (t);
1590 /* If this type has a copy constructor or a destructor, force its
1591 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1592 nonzero. This will cause it to be passed by invisible reference
1593 and prevent it from being returned in a register. */
1594 if (type_has_nontrivial_copy_init (t)
1595 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1598 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1599 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1601 SET_TYPE_MODE (variants, BLKmode);
1602 TREE_ADDRESSABLE (variants) = 1;
1607 /* Issue warnings about T having private constructors, but no friends,
1610 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1611 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1612 non-private static member functions. */
1615 maybe_warn_about_overly_private_class (tree t)
1617 int has_member_fn = 0;
1618 int has_nonprivate_method = 0;
1621 if (!warn_ctor_dtor_privacy
1622 /* If the class has friends, those entities might create and
1623 access instances, so we should not warn. */
1624 || (CLASSTYPE_FRIEND_CLASSES (t)
1625 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1626 /* We will have warned when the template was declared; there's
1627 no need to warn on every instantiation. */
1628 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1629 /* There's no reason to even consider warning about this
1633 /* We only issue one warning, if more than one applies, because
1634 otherwise, on code like:
1637 // Oops - forgot `public:'
1643 we warn several times about essentially the same problem. */
1645 /* Check to see if all (non-constructor, non-destructor) member
1646 functions are private. (Since there are no friends or
1647 non-private statics, we can't ever call any of the private member
1649 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
1650 /* We're not interested in compiler-generated methods; they don't
1651 provide any way to call private members. */
1652 if (!DECL_ARTIFICIAL (fn))
1654 if (!TREE_PRIVATE (fn))
1656 if (DECL_STATIC_FUNCTION_P (fn))
1657 /* A non-private static member function is just like a
1658 friend; it can create and invoke private member
1659 functions, and be accessed without a class
1663 has_nonprivate_method = 1;
1664 /* Keep searching for a static member function. */
1666 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1670 if (!has_nonprivate_method && has_member_fn)
1672 /* There are no non-private methods, and there's at least one
1673 private member function that isn't a constructor or
1674 destructor. (If all the private members are
1675 constructors/destructors we want to use the code below that
1676 issues error messages specifically referring to
1677 constructors/destructors.) */
1679 tree binfo = TYPE_BINFO (t);
1681 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1682 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1684 has_nonprivate_method = 1;
1687 if (!has_nonprivate_method)
1689 warning (OPT_Wctor_dtor_privacy,
1690 "all member functions in class %qT are private", t);
1695 /* Even if some of the member functions are non-private, the class
1696 won't be useful for much if all the constructors or destructors
1697 are private: such an object can never be created or destroyed. */
1698 fn = CLASSTYPE_DESTRUCTORS (t);
1699 if (fn && TREE_PRIVATE (fn))
1701 warning (OPT_Wctor_dtor_privacy,
1702 "%q#T only defines a private destructor and has no friends",
1707 /* Warn about classes that have private constructors and no friends. */
1708 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1709 /* Implicitly generated constructors are always public. */
1710 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1711 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1713 int nonprivate_ctor = 0;
1715 /* If a non-template class does not define a copy
1716 constructor, one is defined for it, enabling it to avoid
1717 this warning. For a template class, this does not
1718 happen, and so we would normally get a warning on:
1720 template <class T> class C { private: C(); };
1722 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1723 complete non-template or fully instantiated classes have this
1725 if (!TYPE_HAS_COPY_CTOR (t))
1726 nonprivate_ctor = 1;
1728 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1730 tree ctor = OVL_CURRENT (fn);
1731 /* Ideally, we wouldn't count copy constructors (or, in
1732 fact, any constructor that takes an argument of the
1733 class type as a parameter) because such things cannot
1734 be used to construct an instance of the class unless
1735 you already have one. But, for now at least, we're
1737 if (! TREE_PRIVATE (ctor))
1739 nonprivate_ctor = 1;
1744 if (nonprivate_ctor == 0)
1746 warning (OPT_Wctor_dtor_privacy,
1747 "%q#T only defines private constructors and has no friends",
1755 gt_pointer_operator new_value;
1759 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1762 method_name_cmp (const void* m1_p, const void* m2_p)
1764 const tree *const m1 = (const tree *) m1_p;
1765 const tree *const m2 = (const tree *) m2_p;
1767 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1769 if (*m1 == NULL_TREE)
1771 if (*m2 == NULL_TREE)
1773 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1778 /* This routine compares two fields like method_name_cmp but using the
1779 pointer operator in resort_field_decl_data. */
1782 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1784 const tree *const m1 = (const tree *) m1_p;
1785 const tree *const m2 = (const tree *) m2_p;
1786 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1788 if (*m1 == NULL_TREE)
1790 if (*m2 == NULL_TREE)
1793 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1794 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1795 resort_data.new_value (&d1, resort_data.cookie);
1796 resort_data.new_value (&d2, resort_data.cookie);
1803 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1806 resort_type_method_vec (void* obj,
1807 void* orig_obj ATTRIBUTE_UNUSED ,
1808 gt_pointer_operator new_value,
1811 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1812 int len = VEC_length (tree, method_vec);
1816 /* The type conversion ops have to live at the front of the vec, so we
1818 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1819 VEC_iterate (tree, method_vec, slot, fn);
1821 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1826 resort_data.new_value = new_value;
1827 resort_data.cookie = cookie;
1828 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1829 resort_method_name_cmp);
1833 /* Warn about duplicate methods in fn_fields.
1835 Sort methods that are not special (i.e., constructors, destructors,
1836 and type conversion operators) so that we can find them faster in
1840 finish_struct_methods (tree t)
1843 VEC(tree,gc) *method_vec;
1846 method_vec = CLASSTYPE_METHOD_VEC (t);
1850 len = VEC_length (tree, method_vec);
1852 /* Clear DECL_IN_AGGR_P for all functions. */
1853 for (fn_fields = TYPE_METHODS (t); fn_fields;
1854 fn_fields = DECL_CHAIN (fn_fields))
1855 DECL_IN_AGGR_P (fn_fields) = 0;
1857 /* Issue warnings about private constructors and such. If there are
1858 no methods, then some public defaults are generated. */
1859 maybe_warn_about_overly_private_class (t);
1861 /* The type conversion ops have to live at the front of the vec, so we
1863 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1864 VEC_iterate (tree, method_vec, slot, fn_fields);
1866 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1869 qsort (VEC_address (tree, method_vec) + slot,
1870 len-slot, sizeof (tree), method_name_cmp);
1873 /* Make BINFO's vtable have N entries, including RTTI entries,
1874 vbase and vcall offsets, etc. Set its type and call the back end
1878 layout_vtable_decl (tree binfo, int n)
1883 atype = build_array_of_n_type (vtable_entry_type, n);
1884 layout_type (atype);
1886 /* We may have to grow the vtable. */
1887 vtable = get_vtbl_decl_for_binfo (binfo);
1888 if (!same_type_p (TREE_TYPE (vtable), atype))
1890 TREE_TYPE (vtable) = atype;
1891 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1892 layout_decl (vtable, 0);
1896 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1897 have the same signature. */
1900 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1902 /* One destructor overrides another if they are the same kind of
1904 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1905 && special_function_p (base_fndecl) == special_function_p (fndecl))
1907 /* But a non-destructor never overrides a destructor, nor vice
1908 versa, nor do different kinds of destructors override
1909 one-another. For example, a complete object destructor does not
1910 override a deleting destructor. */
1911 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1914 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1915 || (DECL_CONV_FN_P (fndecl)
1916 && DECL_CONV_FN_P (base_fndecl)
1917 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1918 DECL_CONV_FN_TYPE (base_fndecl))))
1920 tree types, base_types;
1921 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1922 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1923 if ((cp_type_quals (TREE_TYPE (TREE_VALUE (base_types)))
1924 == cp_type_quals (TREE_TYPE (TREE_VALUE (types))))
1925 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1931 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1935 base_derived_from (tree derived, tree base)
1939 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1941 if (probe == derived)
1943 else if (BINFO_VIRTUAL_P (probe))
1944 /* If we meet a virtual base, we can't follow the inheritance
1945 any more. See if the complete type of DERIVED contains
1946 such a virtual base. */
1947 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1953 typedef struct find_final_overrider_data_s {
1954 /* The function for which we are trying to find a final overrider. */
1956 /* The base class in which the function was declared. */
1957 tree declaring_base;
1958 /* The candidate overriders. */
1960 /* Path to most derived. */
1961 VEC(tree,heap) *path;
1962 } find_final_overrider_data;
1964 /* Add the overrider along the current path to FFOD->CANDIDATES.
1965 Returns true if an overrider was found; false otherwise. */
1968 dfs_find_final_overrider_1 (tree binfo,
1969 find_final_overrider_data *ffod,
1974 /* If BINFO is not the most derived type, try a more derived class.
1975 A definition there will overrider a definition here. */
1979 if (dfs_find_final_overrider_1
1980 (VEC_index (tree, ffod->path, depth), ffod, depth))
1984 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1987 tree *candidate = &ffod->candidates;
1989 /* Remove any candidates overridden by this new function. */
1992 /* If *CANDIDATE overrides METHOD, then METHOD
1993 cannot override anything else on the list. */
1994 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1996 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1997 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1998 *candidate = TREE_CHAIN (*candidate);
2000 candidate = &TREE_CHAIN (*candidate);
2003 /* Add the new function. */
2004 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
2011 /* Called from find_final_overrider via dfs_walk. */
2014 dfs_find_final_overrider_pre (tree binfo, void *data)
2016 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
2018 if (binfo == ffod->declaring_base)
2019 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
2020 VEC_safe_push (tree, heap, ffod->path, binfo);
2026 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
2028 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
2029 VEC_pop (tree, ffod->path);
2034 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
2035 FN and whose TREE_VALUE is the binfo for the base where the
2036 overriding occurs. BINFO (in the hierarchy dominated by the binfo
2037 DERIVED) is the base object in which FN is declared. */
2040 find_final_overrider (tree derived, tree binfo, tree fn)
2042 find_final_overrider_data ffod;
2044 /* Getting this right is a little tricky. This is valid:
2046 struct S { virtual void f (); };
2047 struct T { virtual void f (); };
2048 struct U : public S, public T { };
2050 even though calling `f' in `U' is ambiguous. But,
2052 struct R { virtual void f(); };
2053 struct S : virtual public R { virtual void f (); };
2054 struct T : virtual public R { virtual void f (); };
2055 struct U : public S, public T { };
2057 is not -- there's no way to decide whether to put `S::f' or
2058 `T::f' in the vtable for `R'.
2060 The solution is to look at all paths to BINFO. If we find
2061 different overriders along any two, then there is a problem. */
2062 if (DECL_THUNK_P (fn))
2063 fn = THUNK_TARGET (fn);
2065 /* Determine the depth of the hierarchy. */
2067 ffod.declaring_base = binfo;
2068 ffod.candidates = NULL_TREE;
2069 ffod.path = VEC_alloc (tree, heap, 30);
2071 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2072 dfs_find_final_overrider_post, &ffod);
2074 VEC_free (tree, heap, ffod.path);
2076 /* If there was no winner, issue an error message. */
2077 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2078 return error_mark_node;
2080 return ffod.candidates;
2083 /* Return the index of the vcall offset for FN when TYPE is used as a
2087 get_vcall_index (tree fn, tree type)
2089 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2093 FOR_EACH_VEC_ELT (tree_pair_s, indices, ix, p)
2094 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2095 || same_signature_p (fn, p->purpose))
2098 /* There should always be an appropriate index. */
2102 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2103 dominated by T. FN is the old function; VIRTUALS points to the
2104 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2105 of that entry in the list. */
2108 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2116 tree overrider_fn, overrider_target;
2117 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2118 tree over_return, base_return;
2121 /* Find the nearest primary base (possibly binfo itself) which defines
2122 this function; this is the class the caller will convert to when
2123 calling FN through BINFO. */
2124 for (b = binfo; ; b = get_primary_binfo (b))
2127 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2130 /* The nearest definition is from a lost primary. */
2131 if (BINFO_LOST_PRIMARY_P (b))
2136 /* Find the final overrider. */
2137 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2138 if (overrider == error_mark_node)
2140 error ("no unique final overrider for %qD in %qT", target_fn, t);
2143 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2145 /* Check for adjusting covariant return types. */
2146 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2147 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2149 if (POINTER_TYPE_P (over_return)
2150 && TREE_CODE (over_return) == TREE_CODE (base_return)
2151 && CLASS_TYPE_P (TREE_TYPE (over_return))
2152 && CLASS_TYPE_P (TREE_TYPE (base_return))
2153 /* If the overrider is invalid, don't even try. */
2154 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2156 /* If FN is a covariant thunk, we must figure out the adjustment
2157 to the final base FN was converting to. As OVERRIDER_TARGET might
2158 also be converting to the return type of FN, we have to
2159 combine the two conversions here. */
2160 tree fixed_offset, virtual_offset;
2162 over_return = TREE_TYPE (over_return);
2163 base_return = TREE_TYPE (base_return);
2165 if (DECL_THUNK_P (fn))
2167 gcc_assert (DECL_RESULT_THUNK_P (fn));
2168 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2169 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2172 fixed_offset = virtual_offset = NULL_TREE;
2175 /* Find the equivalent binfo within the return type of the
2176 overriding function. We will want the vbase offset from
2178 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2180 else if (!same_type_ignoring_top_level_qualifiers_p
2181 (over_return, base_return))
2183 /* There was no existing virtual thunk (which takes
2184 precedence). So find the binfo of the base function's
2185 return type within the overriding function's return type.
2186 We cannot call lookup base here, because we're inside a
2187 dfs_walk, and will therefore clobber the BINFO_MARKED
2188 flags. Fortunately we know the covariancy is valid (it
2189 has already been checked), so we can just iterate along
2190 the binfos, which have been chained in inheritance graph
2191 order. Of course it is lame that we have to repeat the
2192 search here anyway -- we should really be caching pieces
2193 of the vtable and avoiding this repeated work. */
2194 tree thunk_binfo, base_binfo;
2196 /* Find the base binfo within the overriding function's
2197 return type. We will always find a thunk_binfo, except
2198 when the covariancy is invalid (which we will have
2199 already diagnosed). */
2200 for (base_binfo = TYPE_BINFO (base_return),
2201 thunk_binfo = TYPE_BINFO (over_return);
2203 thunk_binfo = TREE_CHAIN (thunk_binfo))
2204 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2205 BINFO_TYPE (base_binfo)))
2208 /* See if virtual inheritance is involved. */
2209 for (virtual_offset = thunk_binfo;
2211 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2212 if (BINFO_VIRTUAL_P (virtual_offset))
2216 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2218 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2222 /* We convert via virtual base. Adjust the fixed
2223 offset to be from there. */
2225 size_diffop (offset,
2227 BINFO_OFFSET (virtual_offset)));
2230 /* There was an existing fixed offset, this must be
2231 from the base just converted to, and the base the
2232 FN was thunking to. */
2233 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2235 fixed_offset = offset;
2239 if (fixed_offset || virtual_offset)
2240 /* Replace the overriding function with a covariant thunk. We
2241 will emit the overriding function in its own slot as
2243 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2244 fixed_offset, virtual_offset);
2247 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2248 !DECL_THUNK_P (fn));
2250 /* If we need a covariant thunk, then we may need to adjust first_defn.
2251 The ABI specifies that the thunks emitted with a function are
2252 determined by which bases the function overrides, so we need to be
2253 sure that we're using a thunk for some overridden base; even if we
2254 know that the necessary this adjustment is zero, there may not be an
2255 appropriate zero-this-adjusment thunk for us to use since thunks for
2256 overriding virtual bases always use the vcall offset.
2258 Furthermore, just choosing any base that overrides this function isn't
2259 quite right, as this slot won't be used for calls through a type that
2260 puts a covariant thunk here. Calling the function through such a type
2261 will use a different slot, and that slot is the one that determines
2262 the thunk emitted for that base.
2264 So, keep looking until we find the base that we're really overriding
2265 in this slot: the nearest primary base that doesn't use a covariant
2266 thunk in this slot. */
2267 if (overrider_target != overrider_fn)
2269 if (BINFO_TYPE (b) == DECL_CONTEXT (overrider_target))
2270 /* We already know that the overrider needs a covariant thunk. */
2271 b = get_primary_binfo (b);
2272 for (; ; b = get_primary_binfo (b))
2274 tree main_binfo = TYPE_BINFO (BINFO_TYPE (b));
2275 tree bv = chain_index (ix, BINFO_VIRTUALS (main_binfo));
2276 if (!DECL_THUNK_P (TREE_VALUE (bv)))
2278 if (BINFO_LOST_PRIMARY_P (b))
2284 /* Assume that we will produce a thunk that convert all the way to
2285 the final overrider, and not to an intermediate virtual base. */
2286 virtual_base = NULL_TREE;
2288 /* See if we can convert to an intermediate virtual base first, and then
2289 use the vcall offset located there to finish the conversion. */
2290 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2292 /* If we find the final overrider, then we can stop
2294 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2295 BINFO_TYPE (TREE_VALUE (overrider))))
2298 /* If we find a virtual base, and we haven't yet found the
2299 overrider, then there is a virtual base between the
2300 declaring base (first_defn) and the final overrider. */
2301 if (BINFO_VIRTUAL_P (b))
2308 /* Compute the constant adjustment to the `this' pointer. The
2309 `this' pointer, when this function is called, will point at BINFO
2310 (or one of its primary bases, which are at the same offset). */
2312 /* The `this' pointer needs to be adjusted from the declaration to
2313 the nearest virtual base. */
2314 delta = size_diffop_loc (input_location,
2315 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2316 convert (ssizetype, BINFO_OFFSET (first_defn)));
2318 /* If the nearest definition is in a lost primary, we don't need an
2319 entry in our vtable. Except possibly in a constructor vtable,
2320 if we happen to get our primary back. In that case, the offset
2321 will be zero, as it will be a primary base. */
2322 delta = size_zero_node;
2324 /* The `this' pointer needs to be adjusted from pointing to
2325 BINFO to pointing at the base where the final overrider
2327 delta = size_diffop_loc (input_location,
2329 BINFO_OFFSET (TREE_VALUE (overrider))),
2330 convert (ssizetype, BINFO_OFFSET (binfo)));
2332 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2335 BV_VCALL_INDEX (*virtuals)
2336 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2338 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2340 BV_LOST_PRIMARY (*virtuals) = lost;
2343 /* Called from modify_all_vtables via dfs_walk. */
2346 dfs_modify_vtables (tree binfo, void* data)
2348 tree t = (tree) data;
2353 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2354 /* A base without a vtable needs no modification, and its bases
2355 are uninteresting. */
2356 return dfs_skip_bases;
2358 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2359 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2360 /* Don't do the primary vtable, if it's new. */
2363 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2364 /* There's no need to modify the vtable for a non-virtual primary
2365 base; we're not going to use that vtable anyhow. We do still
2366 need to do this for virtual primary bases, as they could become
2367 non-primary in a construction vtable. */
2370 make_new_vtable (t, binfo);
2372 /* Now, go through each of the virtual functions in the virtual
2373 function table for BINFO. Find the final overrider, and update
2374 the BINFO_VIRTUALS list appropriately. */
2375 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2376 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2378 ix++, virtuals = TREE_CHAIN (virtuals),
2379 old_virtuals = TREE_CHAIN (old_virtuals))
2380 update_vtable_entry_for_fn (t,
2382 BV_FN (old_virtuals),
2388 /* Update all of the primary and secondary vtables for T. Create new
2389 vtables as required, and initialize their RTTI information. Each
2390 of the functions in VIRTUALS is declared in T and may override a
2391 virtual function from a base class; find and modify the appropriate
2392 entries to point to the overriding functions. Returns a list, in
2393 declaration order, of the virtual functions that are declared in T,
2394 but do not appear in the primary base class vtable, and which
2395 should therefore be appended to the end of the vtable for T. */
2398 modify_all_vtables (tree t, tree virtuals)
2400 tree binfo = TYPE_BINFO (t);
2403 /* Update all of the vtables. */
2404 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2406 /* Add virtual functions not already in our primary vtable. These
2407 will be both those introduced by this class, and those overridden
2408 from secondary bases. It does not include virtuals merely
2409 inherited from secondary bases. */
2410 for (fnsp = &virtuals; *fnsp; )
2412 tree fn = TREE_VALUE (*fnsp);
2414 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2415 || DECL_VINDEX (fn) == error_mark_node)
2417 /* We don't need to adjust the `this' pointer when
2418 calling this function. */
2419 BV_DELTA (*fnsp) = integer_zero_node;
2420 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2422 /* This is a function not already in our vtable. Keep it. */
2423 fnsp = &TREE_CHAIN (*fnsp);
2426 /* We've already got an entry for this function. Skip it. */
2427 *fnsp = TREE_CHAIN (*fnsp);
2433 /* Get the base virtual function declarations in T that have the
2437 get_basefndecls (tree name, tree t)
2440 tree base_fndecls = NULL_TREE;
2441 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2444 /* Find virtual functions in T with the indicated NAME. */
2445 i = lookup_fnfields_1 (t, name);
2447 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2449 methods = OVL_NEXT (methods))
2451 tree method = OVL_CURRENT (methods);
2453 if (TREE_CODE (method) == FUNCTION_DECL
2454 && DECL_VINDEX (method))
2455 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2459 return base_fndecls;
2461 for (i = 0; i < n_baseclasses; i++)
2463 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2464 base_fndecls = chainon (get_basefndecls (name, basetype),
2468 return base_fndecls;
2471 /* If this declaration supersedes the declaration of
2472 a method declared virtual in the base class, then
2473 mark this field as being virtual as well. */
2476 check_for_override (tree decl, tree ctype)
2478 bool overrides_found = false;
2479 if (TREE_CODE (decl) == TEMPLATE_DECL)
2480 /* In [temp.mem] we have:
2482 A specialization of a member function template does not
2483 override a virtual function from a base class. */
2485 if ((DECL_DESTRUCTOR_P (decl)
2486 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2487 || DECL_CONV_FN_P (decl))
2488 && look_for_overrides (ctype, decl)
2489 && !DECL_STATIC_FUNCTION_P (decl))
2490 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2491 the error_mark_node so that we know it is an overriding
2494 DECL_VINDEX (decl) = decl;
2495 overrides_found = true;
2498 if (DECL_VIRTUAL_P (decl))
2500 if (!DECL_VINDEX (decl))
2501 DECL_VINDEX (decl) = error_mark_node;
2502 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2503 if (DECL_DESTRUCTOR_P (decl))
2504 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (ctype) = true;
2506 else if (DECL_FINAL_P (decl))
2507 error ("%q+#D marked final, but is not virtual", decl);
2508 if (DECL_OVERRIDE_P (decl) && !overrides_found)
2509 error ("%q+#D marked override, but does not override", decl);
2512 /* Warn about hidden virtual functions that are not overridden in t.
2513 We know that constructors and destructors don't apply. */
2516 warn_hidden (tree t)
2518 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2522 /* We go through each separately named virtual function. */
2523 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2524 VEC_iterate (tree, method_vec, i, fns);
2535 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2536 have the same name. Figure out what name that is. */
2537 name = DECL_NAME (OVL_CURRENT (fns));
2538 /* There are no possibly hidden functions yet. */
2539 base_fndecls = NULL_TREE;
2540 /* Iterate through all of the base classes looking for possibly
2541 hidden functions. */
2542 for (binfo = TYPE_BINFO (t), j = 0;
2543 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2545 tree basetype = BINFO_TYPE (base_binfo);
2546 base_fndecls = chainon (get_basefndecls (name, basetype),
2550 /* If there are no functions to hide, continue. */
2554 /* Remove any overridden functions. */
2555 for (fn = fns; fn; fn = OVL_NEXT (fn))
2557 fndecl = OVL_CURRENT (fn);
2558 if (DECL_VINDEX (fndecl))
2560 tree *prev = &base_fndecls;
2563 /* If the method from the base class has the same
2564 signature as the method from the derived class, it
2565 has been overridden. */
2566 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2567 *prev = TREE_CHAIN (*prev);
2569 prev = &TREE_CHAIN (*prev);
2573 /* Now give a warning for all base functions without overriders,
2574 as they are hidden. */
2575 while (base_fndecls)
2577 /* Here we know it is a hider, and no overrider exists. */
2578 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2579 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2580 base_fndecls = TREE_CHAIN (base_fndecls);
2585 /* Check for things that are invalid. There are probably plenty of other
2586 things we should check for also. */
2589 finish_struct_anon (tree t)
2593 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
2595 if (TREE_STATIC (field))
2597 if (TREE_CODE (field) != FIELD_DECL)
2600 if (DECL_NAME (field) == NULL_TREE
2601 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2603 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2604 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2605 for (; elt; elt = DECL_CHAIN (elt))
2607 /* We're generally only interested in entities the user
2608 declared, but we also find nested classes by noticing
2609 the TYPE_DECL that we create implicitly. You're
2610 allowed to put one anonymous union inside another,
2611 though, so we explicitly tolerate that. We use
2612 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2613 we also allow unnamed types used for defining fields. */
2614 if (DECL_ARTIFICIAL (elt)
2615 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2616 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2619 if (TREE_CODE (elt) != FIELD_DECL)
2622 permerror (input_location, "%q+#D invalid; an anonymous union can "
2623 "only have non-static data members", elt);
2625 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2626 "only have non-static data members", elt);
2630 if (TREE_PRIVATE (elt))
2633 permerror (input_location, "private member %q+#D in anonymous union", elt);
2635 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2637 else if (TREE_PROTECTED (elt))
2640 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2642 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2645 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2646 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2652 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2653 will be used later during class template instantiation.
2654 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2655 a non-static member data (FIELD_DECL), a member function
2656 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2657 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2658 When FRIEND_P is nonzero, T is either a friend class
2659 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2660 (FUNCTION_DECL, TEMPLATE_DECL). */
2663 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2665 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2666 if (CLASSTYPE_TEMPLATE_INFO (type))
2667 CLASSTYPE_DECL_LIST (type)
2668 = tree_cons (friend_p ? NULL_TREE : type,
2669 t, CLASSTYPE_DECL_LIST (type));
2672 /* This function is called from declare_virt_assop_and_dtor via
2675 DATA is a type that direcly or indirectly inherits the base
2676 represented by BINFO. If BINFO contains a virtual assignment [copy
2677 assignment or move assigment] operator or a virtual constructor,
2678 declare that function in DATA if it hasn't been already declared. */
2681 dfs_declare_virt_assop_and_dtor (tree binfo, void *data)
2683 tree bv, fn, t = (tree)data;
2684 tree opname = ansi_assopname (NOP_EXPR);
2686 gcc_assert (t && CLASS_TYPE_P (t));
2687 gcc_assert (binfo && TREE_CODE (binfo) == TREE_BINFO);
2689 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2690 /* A base without a vtable needs no modification, and its bases
2691 are uninteresting. */
2692 return dfs_skip_bases;
2694 if (BINFO_PRIMARY_P (binfo))
2695 /* If this is a primary base, then we have already looked at the
2696 virtual functions of its vtable. */
2699 for (bv = BINFO_VIRTUALS (binfo); bv; bv = TREE_CHAIN (bv))
2703 if (DECL_NAME (fn) == opname)
2705 if (CLASSTYPE_LAZY_COPY_ASSIGN (t))
2706 lazily_declare_fn (sfk_copy_assignment, t);
2707 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
2708 lazily_declare_fn (sfk_move_assignment, t);
2710 else if (DECL_DESTRUCTOR_P (fn)
2711 && CLASSTYPE_LAZY_DESTRUCTOR (t))
2712 lazily_declare_fn (sfk_destructor, t);
2718 /* If the class type T has a direct or indirect base that contains a
2719 virtual assignment operator or a virtual destructor, declare that
2720 function in T if it hasn't been already declared. */
2723 declare_virt_assop_and_dtor (tree t)
2725 if (!(TYPE_POLYMORPHIC_P (t)
2726 && (CLASSTYPE_LAZY_COPY_ASSIGN (t)
2727 || CLASSTYPE_LAZY_MOVE_ASSIGN (t)
2728 || CLASSTYPE_LAZY_DESTRUCTOR (t))))
2731 dfs_walk_all (TYPE_BINFO (t),
2732 dfs_declare_virt_assop_and_dtor,
2736 /* Create default constructors, assignment operators, and so forth for
2737 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2738 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2739 the class cannot have a default constructor, copy constructor
2740 taking a const reference argument, or an assignment operator taking
2741 a const reference, respectively. */
2744 add_implicitly_declared_members (tree t,
2745 int cant_have_const_cctor,
2746 int cant_have_const_assignment)
2748 bool move_ok = false;
2750 if (cxx_dialect >= cxx0x && !CLASSTYPE_DESTRUCTORS (t)
2751 && !TYPE_HAS_COPY_CTOR (t) && !TYPE_HAS_COPY_ASSIGN (t)
2752 && !type_has_move_constructor (t) && !type_has_move_assign (t))
2756 if (!CLASSTYPE_DESTRUCTORS (t))
2758 /* In general, we create destructors lazily. */
2759 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2761 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2762 && TYPE_FOR_JAVA (t))
2763 /* But if this is a Java class, any non-trivial destructor is
2764 invalid, even if compiler-generated. Therefore, if the
2765 destructor is non-trivial we create it now. */
2766 lazily_declare_fn (sfk_destructor, t);
2771 If there is no user-declared constructor for a class, a default
2772 constructor is implicitly declared. */
2773 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2775 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2776 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2777 if (cxx_dialect >= cxx0x)
2778 TYPE_HAS_CONSTEXPR_CTOR (t)
2779 /* This might force the declaration. */
2780 = type_has_constexpr_default_constructor (t);
2785 If a class definition does not explicitly declare a copy
2786 constructor, one is declared implicitly. */
2787 if (! TYPE_HAS_COPY_CTOR (t) && ! TYPE_FOR_JAVA (t))
2789 TYPE_HAS_COPY_CTOR (t) = 1;
2790 TYPE_HAS_CONST_COPY_CTOR (t) = !cant_have_const_cctor;
2791 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2793 CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
2796 /* If there is no assignment operator, one will be created if and
2797 when it is needed. For now, just record whether or not the type
2798 of the parameter to the assignment operator will be a const or
2799 non-const reference. */
2800 if (!TYPE_HAS_COPY_ASSIGN (t) && !TYPE_FOR_JAVA (t))
2802 TYPE_HAS_COPY_ASSIGN (t) = 1;
2803 TYPE_HAS_CONST_COPY_ASSIGN (t) = !cant_have_const_assignment;
2804 CLASSTYPE_LAZY_COPY_ASSIGN (t) = 1;
2806 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 1;
2809 /* We can't be lazy about declaring functions that might override
2810 a virtual function from a base class. */
2811 declare_virt_assop_and_dtor (t);
2814 /* Subroutine of finish_struct_1. Recursively count the number of fields
2815 in TYPE, including anonymous union members. */
2818 count_fields (tree fields)
2822 for (x = fields; x; x = DECL_CHAIN (x))
2824 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2825 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2832 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2833 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2836 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2839 for (x = fields; x; x = DECL_CHAIN (x))
2841 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2842 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2844 field_vec->elts[idx++] = x;
2849 /* FIELD is a bit-field. We are finishing the processing for its
2850 enclosing type. Issue any appropriate messages and set appropriate
2851 flags. Returns false if an error has been diagnosed. */
2854 check_bitfield_decl (tree field)
2856 tree type = TREE_TYPE (field);
2859 /* Extract the declared width of the bitfield, which has been
2860 temporarily stashed in DECL_INITIAL. */
2861 w = DECL_INITIAL (field);
2862 gcc_assert (w != NULL_TREE);
2863 /* Remove the bit-field width indicator so that the rest of the
2864 compiler does not treat that value as an initializer. */
2865 DECL_INITIAL (field) = NULL_TREE;
2867 /* Detect invalid bit-field type. */
2868 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2870 error ("bit-field %q+#D with non-integral type", field);
2871 w = error_mark_node;
2875 location_t loc = input_location;
2876 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2879 /* detect invalid field size. */
2880 input_location = DECL_SOURCE_LOCATION (field);
2881 w = cxx_constant_value (w);
2882 input_location = loc;
2884 if (TREE_CODE (w) != INTEGER_CST)
2886 error ("bit-field %q+D width not an integer constant", field);
2887 w = error_mark_node;
2889 else if (tree_int_cst_sgn (w) < 0)
2891 error ("negative width in bit-field %q+D", field);
2892 w = error_mark_node;
2894 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2896 error ("zero width for bit-field %q+D", field);
2897 w = error_mark_node;
2899 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2900 && TREE_CODE (type) != ENUMERAL_TYPE
2901 && TREE_CODE (type) != BOOLEAN_TYPE)
2902 warning (0, "width of %q+D exceeds its type", field);
2903 else if (TREE_CODE (type) == ENUMERAL_TYPE
2904 && (0 > (compare_tree_int
2905 (w, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type))))))
2906 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2909 if (w != error_mark_node)
2911 DECL_SIZE (field) = convert (bitsizetype, w);
2912 DECL_BIT_FIELD (field) = 1;
2917 /* Non-bit-fields are aligned for their type. */
2918 DECL_BIT_FIELD (field) = 0;
2919 CLEAR_DECL_C_BIT_FIELD (field);
2924 /* FIELD is a non bit-field. We are finishing the processing for its
2925 enclosing type T. Issue any appropriate messages and set appropriate
2929 check_field_decl (tree field,
2931 int* cant_have_const_ctor,
2932 int* no_const_asn_ref,
2933 int* any_default_members)
2935 tree type = strip_array_types (TREE_TYPE (field));
2937 /* In C++98 an anonymous union cannot contain any fields which would change
2938 the settings of CANT_HAVE_CONST_CTOR and friends. */
2939 if (ANON_UNION_TYPE_P (type) && cxx_dialect < cxx0x)
2941 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2942 structs. So, we recurse through their fields here. */
2943 else if (ANON_AGGR_TYPE_P (type))
2947 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2948 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2949 check_field_decl (fields, t, cant_have_const_ctor,
2950 no_const_asn_ref, any_default_members);
2952 /* Check members with class type for constructors, destructors,
2954 else if (CLASS_TYPE_P (type))
2956 /* Never let anything with uninheritable virtuals
2957 make it through without complaint. */
2958 abstract_virtuals_error (field, type);
2960 if (TREE_CODE (t) == UNION_TYPE && cxx_dialect < cxx0x)
2963 int oldcount = errorcount;
2964 if (TYPE_NEEDS_CONSTRUCTING (type))
2965 error ("member %q+#D with constructor not allowed in union",
2967 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2968 error ("member %q+#D with destructor not allowed in union", field);
2969 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
2970 error ("member %q+#D with copy assignment operator not allowed in union",
2972 if (!warned && errorcount > oldcount)
2974 inform (DECL_SOURCE_LOCATION (field), "unrestricted unions "
2975 "only available with -std=c++11 or -std=gnu++11");
2981 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2982 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2983 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2984 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
2985 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type)
2986 || !TYPE_HAS_COPY_ASSIGN (type));
2987 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type)
2988 || !TYPE_HAS_COPY_CTOR (type));
2989 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type);
2990 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type);
2991 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type)
2992 || TYPE_HAS_COMPLEX_DFLT (type));
2995 if (TYPE_HAS_COPY_CTOR (type)
2996 && !TYPE_HAS_CONST_COPY_CTOR (type))
2997 *cant_have_const_ctor = 1;
2999 if (TYPE_HAS_COPY_ASSIGN (type)
3000 && !TYPE_HAS_CONST_COPY_ASSIGN (type))
3001 *no_const_asn_ref = 1;
3003 if (DECL_INITIAL (field) != NULL_TREE)
3005 /* `build_class_init_list' does not recognize
3007 if (TREE_CODE (t) == UNION_TYPE && *any_default_members != 0)
3008 error ("multiple fields in union %qT initialized", t);
3009 *any_default_members = 1;
3013 /* Check the data members (both static and non-static), class-scoped
3014 typedefs, etc., appearing in the declaration of T. Issue
3015 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
3016 declaration order) of access declarations; each TREE_VALUE in this
3017 list is a USING_DECL.
3019 In addition, set the following flags:
3022 The class is empty, i.e., contains no non-static data members.
3024 CANT_HAVE_CONST_CTOR_P
3025 This class cannot have an implicitly generated copy constructor
3026 taking a const reference.
3028 CANT_HAVE_CONST_ASN_REF
3029 This class cannot have an implicitly generated assignment
3030 operator taking a const reference.
3032 All of these flags should be initialized before calling this
3035 Returns a pointer to the end of the TYPE_FIELDs chain; additional
3036 fields can be added by adding to this chain. */
3039 check_field_decls (tree t, tree *access_decls,
3040 int *cant_have_const_ctor_p,
3041 int *no_const_asn_ref_p)
3046 int any_default_members;
3048 int field_access = -1;
3050 /* Assume there are no access declarations. */
3051 *access_decls = NULL_TREE;
3052 /* Assume this class has no pointer members. */
3053 has_pointers = false;
3054 /* Assume none of the members of this class have default
3056 any_default_members = 0;
3058 for (field = &TYPE_FIELDS (t); *field; field = next)
3061 tree type = TREE_TYPE (x);
3062 int this_field_access;
3064 next = &DECL_CHAIN (x);
3066 if (TREE_CODE (x) == USING_DECL)
3068 /* Save the access declarations for our caller. */
3069 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
3073 if (TREE_CODE (x) == TYPE_DECL
3074 || TREE_CODE (x) == TEMPLATE_DECL)
3077 /* If we've gotten this far, it's a data member, possibly static,
3078 or an enumerator. */
3079 DECL_CONTEXT (x) = t;
3081 /* When this goes into scope, it will be a non-local reference. */
3082 DECL_NONLOCAL (x) = 1;
3084 if (TREE_CODE (t) == UNION_TYPE)
3088 If a union contains a static data member, or a member of
3089 reference type, the program is ill-formed. */
3090 if (TREE_CODE (x) == VAR_DECL)
3092 error ("%q+D may not be static because it is a member of a union", x);
3095 if (TREE_CODE (type) == REFERENCE_TYPE)
3097 error ("%q+D may not have reference type %qT because"
3098 " it is a member of a union",
3104 /* Perform error checking that did not get done in
3106 if (TREE_CODE (type) == FUNCTION_TYPE)
3108 error ("field %q+D invalidly declared function type", x);
3109 type = build_pointer_type (type);
3110 TREE_TYPE (x) = type;
3112 else if (TREE_CODE (type) == METHOD_TYPE)
3114 error ("field %q+D invalidly declared method type", x);
3115 type = build_pointer_type (type);
3116 TREE_TYPE (x) = type;
3119 if (type == error_mark_node)
3122 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
3125 /* Now it can only be a FIELD_DECL. */
3127 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3128 CLASSTYPE_NON_AGGREGATE (t) = 1;
3130 /* If at least one non-static data member is non-literal, the whole
3131 class becomes non-literal. */
3132 if (!literal_type_p (type))
3133 CLASSTYPE_LITERAL_P (t) = false;
3135 /* A standard-layout class is a class that:
3137 has the same access control (Clause 11) for all non-static data members,
3139 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3140 if (field_access == -1)
3141 field_access = this_field_access;
3142 else if (this_field_access != field_access)
3143 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3145 /* If this is of reference type, check if it needs an init. */
3146 if (TREE_CODE (type) == REFERENCE_TYPE)
3148 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3149 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3150 if (DECL_INITIAL (x) == NULL_TREE)
3151 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3153 /* ARM $12.6.2: [A member initializer list] (or, for an
3154 aggregate, initialization by a brace-enclosed list) is the
3155 only way to initialize nonstatic const and reference
3157 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3158 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3161 type = strip_array_types (type);
3163 if (TYPE_PACKED (t))
3165 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3169 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3173 else if (DECL_C_BIT_FIELD (x)
3174 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3175 DECL_PACKED (x) = 1;
3178 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3179 /* We don't treat zero-width bitfields as making a class
3184 /* The class is non-empty. */
3185 CLASSTYPE_EMPTY_P (t) = 0;
3186 /* The class is not even nearly empty. */
3187 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3188 /* If one of the data members contains an empty class,
3190 if (CLASS_TYPE_P (type)
3191 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3192 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3195 /* This is used by -Weffc++ (see below). Warn only for pointers
3196 to members which might hold dynamic memory. So do not warn
3197 for pointers to functions or pointers to members. */
3198 if (TYPE_PTR_P (type)
3199 && !TYPE_PTRFN_P (type)
3200 && !TYPE_PTR_TO_MEMBER_P (type))
3201 has_pointers = true;
3203 if (CLASS_TYPE_P (type))
3205 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3206 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3207 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3208 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3211 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3212 CLASSTYPE_HAS_MUTABLE (t) = 1;
3214 if (! layout_pod_type_p (type))
3215 /* DR 148 now allows pointers to members (which are POD themselves),
3216 to be allowed in POD structs. */
3217 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3219 if (!std_layout_type_p (type))
3220 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3222 if (! zero_init_p (type))
3223 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3225 /* We set DECL_C_BIT_FIELD in grokbitfield.
3226 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3227 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3228 check_field_decl (x, t,
3229 cant_have_const_ctor_p,
3231 &any_default_members);
3233 /* Now that we've removed bit-field widths from DECL_INITIAL,
3234 anything left in DECL_INITIAL is an NSDMI that makes the class
3236 if (DECL_INITIAL (x))
3237 CLASSTYPE_NON_AGGREGATE (t) = true;
3239 /* If any field is const, the structure type is pseudo-const. */
3240 if (CP_TYPE_CONST_P (type))
3242 C_TYPE_FIELDS_READONLY (t) = 1;
3243 if (DECL_INITIAL (x) == NULL_TREE)
3244 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3246 /* ARM $12.6.2: [A member initializer list] (or, for an
3247 aggregate, initialization by a brace-enclosed list) is the
3248 only way to initialize nonstatic const and reference
3250 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3251 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3253 /* A field that is pseudo-const makes the structure likewise. */
3254 else if (CLASS_TYPE_P (type))
3256 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3257 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3258 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3259 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3262 /* Core issue 80: A nonstatic data member is required to have a
3263 different name from the class iff the class has a
3264 user-declared constructor. */
3265 if (constructor_name_p (DECL_NAME (x), t)
3266 && TYPE_HAS_USER_CONSTRUCTOR (t))
3267 permerror (input_location, "field %q+#D with same name as class", x);
3270 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3271 it should also define a copy constructor and an assignment operator to
3272 implement the correct copy semantic (deep vs shallow, etc.). As it is
3273 not feasible to check whether the constructors do allocate dynamic memory
3274 and store it within members, we approximate the warning like this:
3276 -- Warn only if there are members which are pointers
3277 -- Warn only if there is a non-trivial constructor (otherwise,
3278 there cannot be memory allocated).
3279 -- Warn only if there is a non-trivial destructor. We assume that the
3280 user at least implemented the cleanup correctly, and a destructor
3281 is needed to free dynamic memory.
3283 This seems enough for practical purposes. */
3286 && TYPE_HAS_USER_CONSTRUCTOR (t)
3287 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3288 && !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
3290 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3292 if (! TYPE_HAS_COPY_CTOR (t))
3294 warning (OPT_Weffc__,
3295 " but does not override %<%T(const %T&)%>", t, t);
3296 if (!TYPE_HAS_COPY_ASSIGN (t))
3297 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3299 else if (! TYPE_HAS_COPY_ASSIGN (t))
3300 warning (OPT_Weffc__,
3301 " but does not override %<operator=(const %T&)%>", t);
3304 /* Non-static data member initializers make the default constructor
3306 if (any_default_members)
3308 TYPE_NEEDS_CONSTRUCTING (t) = true;
3309 TYPE_HAS_COMPLEX_DFLT (t) = true;
3312 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3314 TYPE_PACKED (t) = 0;
3316 /* Check anonymous struct/anonymous union fields. */
3317 finish_struct_anon (t);
3319 /* We've built up the list of access declarations in reverse order.
3321 *access_decls = nreverse (*access_decls);
3324 /* If TYPE is an empty class type, records its OFFSET in the table of
3328 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3332 if (!is_empty_class (type))
3335 /* Record the location of this empty object in OFFSETS. */
3336 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3338 n = splay_tree_insert (offsets,
3339 (splay_tree_key) offset,
3340 (splay_tree_value) NULL_TREE);
3341 n->value = ((splay_tree_value)
3342 tree_cons (NULL_TREE,
3349 /* Returns nonzero if TYPE is an empty class type and there is
3350 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3353 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3358 if (!is_empty_class (type))
3361 /* Record the location of this empty object in OFFSETS. */
3362 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3366 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3367 if (same_type_p (TREE_VALUE (t), type))
3373 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3374 F for every subobject, passing it the type, offset, and table of
3375 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3378 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3379 than MAX_OFFSET will not be walked.
3381 If F returns a nonzero value, the traversal ceases, and that value
3382 is returned. Otherwise, returns zero. */
3385 walk_subobject_offsets (tree type,
3386 subobject_offset_fn f,
3393 tree type_binfo = NULL_TREE;
3395 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3397 if (max_offset && INT_CST_LT (max_offset, offset))
3400 if (type == error_mark_node)
3405 if (abi_version_at_least (2))
3407 type = BINFO_TYPE (type);
3410 if (CLASS_TYPE_P (type))
3416 /* Avoid recursing into objects that are not interesting. */
3417 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3420 /* Record the location of TYPE. */
3421 r = (*f) (type, offset, offsets);
3425 /* Iterate through the direct base classes of TYPE. */
3427 type_binfo = TYPE_BINFO (type);
3428 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3432 if (abi_version_at_least (2)
3433 && BINFO_VIRTUAL_P (binfo))
3437 && BINFO_VIRTUAL_P (binfo)
3438 && !BINFO_PRIMARY_P (binfo))
3441 if (!abi_version_at_least (2))
3442 binfo_offset = size_binop (PLUS_EXPR,
3444 BINFO_OFFSET (binfo));
3448 /* We cannot rely on BINFO_OFFSET being set for the base
3449 class yet, but the offsets for direct non-virtual
3450 bases can be calculated by going back to the TYPE. */
3451 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3452 binfo_offset = size_binop (PLUS_EXPR,
3454 BINFO_OFFSET (orig_binfo));
3457 r = walk_subobject_offsets (binfo,
3462 (abi_version_at_least (2)
3463 ? /*vbases_p=*/0 : vbases_p));
3468 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3471 VEC(tree,gc) *vbases;
3473 /* Iterate through the virtual base classes of TYPE. In G++
3474 3.2, we included virtual bases in the direct base class
3475 loop above, which results in incorrect results; the
3476 correct offsets for virtual bases are only known when
3477 working with the most derived type. */
3479 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3480 VEC_iterate (tree, vbases, ix, binfo); ix++)
3482 r = walk_subobject_offsets (binfo,
3484 size_binop (PLUS_EXPR,
3486 BINFO_OFFSET (binfo)),
3495 /* We still have to walk the primary base, if it is
3496 virtual. (If it is non-virtual, then it was walked
3498 tree vbase = get_primary_binfo (type_binfo);
3500 if (vbase && BINFO_VIRTUAL_P (vbase)
3501 && BINFO_PRIMARY_P (vbase)
3502 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3504 r = (walk_subobject_offsets
3506 offsets, max_offset, /*vbases_p=*/0));
3513 /* Iterate through the fields of TYPE. */
3514 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
3515 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3519 if (abi_version_at_least (2))
3520 field_offset = byte_position (field);
3522 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3523 field_offset = DECL_FIELD_OFFSET (field);
3525 r = walk_subobject_offsets (TREE_TYPE (field),
3527 size_binop (PLUS_EXPR,
3537 else if (TREE_CODE (type) == ARRAY_TYPE)
3539 tree element_type = strip_array_types (type);
3540 tree domain = TYPE_DOMAIN (type);
3543 /* Avoid recursing into objects that are not interesting. */
3544 if (!CLASS_TYPE_P (element_type)
3545 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3548 /* Step through each of the elements in the array. */
3549 for (index = size_zero_node;
3550 /* G++ 3.2 had an off-by-one error here. */
3551 (abi_version_at_least (2)
3552 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3553 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3554 index = size_binop (PLUS_EXPR, index, size_one_node))
3556 r = walk_subobject_offsets (TREE_TYPE (type),
3564 offset = size_binop (PLUS_EXPR, offset,
3565 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3566 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3567 there's no point in iterating through the remaining
3568 elements of the array. */
3569 if (max_offset && INT_CST_LT (max_offset, offset))
3577 /* Record all of the empty subobjects of TYPE (either a type or a
3578 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3579 is being placed at OFFSET; otherwise, it is a base class that is
3580 being placed at OFFSET. */
3583 record_subobject_offsets (tree type,
3586 bool is_data_member)
3589 /* If recording subobjects for a non-static data member or a
3590 non-empty base class , we do not need to record offsets beyond
3591 the size of the biggest empty class. Additional data members
3592 will go at the end of the class. Additional base classes will go
3593 either at offset zero (if empty, in which case they cannot
3594 overlap with offsets past the size of the biggest empty class) or
3595 at the end of the class.
3597 However, if we are placing an empty base class, then we must record
3598 all offsets, as either the empty class is at offset zero (where
3599 other empty classes might later be placed) or at the end of the
3600 class (where other objects might then be placed, so other empty
3601 subobjects might later overlap). */
3603 || !is_empty_class (BINFO_TYPE (type)))
3604 max_offset = sizeof_biggest_empty_class;
3606 max_offset = NULL_TREE;
3607 walk_subobject_offsets (type, record_subobject_offset, offset,
3608 offsets, max_offset, is_data_member);
3611 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3612 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3613 virtual bases of TYPE are examined. */
3616 layout_conflict_p (tree type,
3621 splay_tree_node max_node;
3623 /* Get the node in OFFSETS that indicates the maximum offset where
3624 an empty subobject is located. */
3625 max_node = splay_tree_max (offsets);
3626 /* If there aren't any empty subobjects, then there's no point in
3627 performing this check. */
3631 return walk_subobject_offsets (type, check_subobject_offset, offset,
3632 offsets, (tree) (max_node->key),
3636 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3637 non-static data member of the type indicated by RLI. BINFO is the
3638 binfo corresponding to the base subobject, OFFSETS maps offsets to
3639 types already located at those offsets. This function determines
3640 the position of the DECL. */
3643 layout_nonempty_base_or_field (record_layout_info rli,
3648 tree offset = NULL_TREE;
3654 /* For the purposes of determining layout conflicts, we want to
3655 use the class type of BINFO; TREE_TYPE (DECL) will be the
3656 CLASSTYPE_AS_BASE version, which does not contain entries for
3657 zero-sized bases. */
3658 type = TREE_TYPE (binfo);
3663 type = TREE_TYPE (decl);
3667 /* Try to place the field. It may take more than one try if we have
3668 a hard time placing the field without putting two objects of the
3669 same type at the same address. */
3672 struct record_layout_info_s old_rli = *rli;
3674 /* Place this field. */
3675 place_field (rli, decl);
3676 offset = byte_position (decl);
3678 /* We have to check to see whether or not there is already
3679 something of the same type at the offset we're about to use.
3680 For example, consider:
3683 struct T : public S { int i; };
3684 struct U : public S, public T {};
3686 Here, we put S at offset zero in U. Then, we can't put T at
3687 offset zero -- its S component would be at the same address
3688 as the S we already allocated. So, we have to skip ahead.
3689 Since all data members, including those whose type is an
3690 empty class, have nonzero size, any overlap can happen only
3691 with a direct or indirect base-class -- it can't happen with
3693 /* In a union, overlap is permitted; all members are placed at
3695 if (TREE_CODE (rli->t) == UNION_TYPE)
3697 /* G++ 3.2 did not check for overlaps when placing a non-empty
3699 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3701 if (layout_conflict_p (field_p ? type : binfo, offset,
3704 /* Strip off the size allocated to this field. That puts us
3705 at the first place we could have put the field with
3706 proper alignment. */
3709 /* Bump up by the alignment required for the type. */
3711 = size_binop (PLUS_EXPR, rli->bitpos,
3713 ? CLASSTYPE_ALIGN (type)
3714 : TYPE_ALIGN (type)));
3715 normalize_rli (rli);
3718 /* There was no conflict. We're done laying out this field. */
3722 /* Now that we know where it will be placed, update its
3724 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3725 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3726 this point because their BINFO_OFFSET is copied from another
3727 hierarchy. Therefore, we may not need to add the entire
3729 propagate_binfo_offsets (binfo,
3730 size_diffop_loc (input_location,
3731 convert (ssizetype, offset),
3733 BINFO_OFFSET (binfo))));
3736 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3739 empty_base_at_nonzero_offset_p (tree type,
3741 splay_tree offsets ATTRIBUTE_UNUSED)
3743 return is_empty_class (type) && !integer_zerop (offset);
3746 /* Layout the empty base BINFO. EOC indicates the byte currently just
3747 past the end of the class, and should be correctly aligned for a
3748 class of the type indicated by BINFO; OFFSETS gives the offsets of
3749 the empty bases allocated so far. T is the most derived
3750 type. Return nonzero iff we added it at the end. */
3753 layout_empty_base (record_layout_info rli, tree binfo,
3754 tree eoc, splay_tree offsets)
3757 tree basetype = BINFO_TYPE (binfo);
3760 /* This routine should only be used for empty classes. */
3761 gcc_assert (is_empty_class (basetype));
3762 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3764 if (!integer_zerop (BINFO_OFFSET (binfo)))
3766 if (abi_version_at_least (2))
3767 propagate_binfo_offsets
3768 (binfo, size_diffop_loc (input_location,
3769 size_zero_node, BINFO_OFFSET (binfo)));
3772 "offset of empty base %qT may not be ABI-compliant and may"
3773 "change in a future version of GCC",
3774 BINFO_TYPE (binfo));
3777 /* This is an empty base class. We first try to put it at offset
3779 if (layout_conflict_p (binfo,
3780 BINFO_OFFSET (binfo),
3784 /* That didn't work. Now, we move forward from the next
3785 available spot in the class. */
3787 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3790 if (!layout_conflict_p (binfo,
3791 BINFO_OFFSET (binfo),
3794 /* We finally found a spot where there's no overlap. */
3797 /* There's overlap here, too. Bump along to the next spot. */
3798 propagate_binfo_offsets (binfo, alignment);
3802 if (CLASSTYPE_USER_ALIGN (basetype))
3804 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3806 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3807 TYPE_USER_ALIGN (rli->t) = 1;
3813 /* Layout the base given by BINFO in the class indicated by RLI.
3814 *BASE_ALIGN is a running maximum of the alignments of
3815 any base class. OFFSETS gives the location of empty base
3816 subobjects. T is the most derived type. Return nonzero if the new
3817 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3818 *NEXT_FIELD, unless BINFO is for an empty base class.
3820 Returns the location at which the next field should be inserted. */
3823 build_base_field (record_layout_info rli, tree binfo,
3824 splay_tree offsets, tree *next_field)
3827 tree basetype = BINFO_TYPE (binfo);
3829 if (!COMPLETE_TYPE_P (basetype))
3830 /* This error is now reported in xref_tag, thus giving better
3831 location information. */
3834 /* Place the base class. */
3835 if (!is_empty_class (basetype))
3839 /* The containing class is non-empty because it has a non-empty
3841 CLASSTYPE_EMPTY_P (t) = 0;
3843 /* Create the FIELD_DECL. */
3844 decl = build_decl (input_location,
3845 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3846 DECL_ARTIFICIAL (decl) = 1;
3847 DECL_IGNORED_P (decl) = 1;
3848 DECL_FIELD_CONTEXT (decl) = t;
3849 if (CLASSTYPE_AS_BASE (basetype))
3851 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3852 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3853 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3854 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3855 DECL_MODE (decl) = TYPE_MODE (basetype);
3856 DECL_FIELD_IS_BASE (decl) = 1;
3858 /* Try to place the field. It may take more than one try if we
3859 have a hard time placing the field without putting two
3860 objects of the same type at the same address. */
3861 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3862 /* Add the new FIELD_DECL to the list of fields for T. */
3863 DECL_CHAIN (decl) = *next_field;
3865 next_field = &DECL_CHAIN (decl);
3873 /* On some platforms (ARM), even empty classes will not be
3875 eoc = round_up_loc (input_location,
3876 rli_size_unit_so_far (rli),
3877 CLASSTYPE_ALIGN_UNIT (basetype));
3878 atend = layout_empty_base (rli, binfo, eoc, offsets);
3879 /* A nearly-empty class "has no proper base class that is empty,
3880 not morally virtual, and at an offset other than zero." */
3881 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3884 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3885 /* The check above (used in G++ 3.2) is insufficient because
3886 an empty class placed at offset zero might itself have an
3887 empty base at a nonzero offset. */
3888 else if (walk_subobject_offsets (basetype,
3889 empty_base_at_nonzero_offset_p,
3892 /*max_offset=*/NULL_TREE,
3895 if (abi_version_at_least (2))
3896 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3899 "class %qT will be considered nearly empty in a "
3900 "future version of GCC", t);
3904 /* We do not create a FIELD_DECL for empty base classes because
3905 it might overlap some other field. We want to be able to
3906 create CONSTRUCTORs for the class by iterating over the
3907 FIELD_DECLs, and the back end does not handle overlapping
3910 /* An empty virtual base causes a class to be non-empty
3911 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3912 here because that was already done when the virtual table
3913 pointer was created. */
3916 /* Record the offsets of BINFO and its base subobjects. */
3917 record_subobject_offsets (binfo,
3918 BINFO_OFFSET (binfo),
3920 /*is_data_member=*/false);
3925 /* Layout all of the non-virtual base classes. Record empty
3926 subobjects in OFFSETS. T is the most derived type. Return nonzero
3927 if the type cannot be nearly empty. The fields created
3928 corresponding to the base classes will be inserted at
3932 build_base_fields (record_layout_info rli,
3933 splay_tree offsets, tree *next_field)
3935 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3938 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3941 /* The primary base class is always allocated first. */
3942 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3943 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3944 offsets, next_field);
3946 /* Now allocate the rest of the bases. */
3947 for (i = 0; i < n_baseclasses; ++i)
3951 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3953 /* The primary base was already allocated above, so we don't
3954 need to allocate it again here. */
3955 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3958 /* Virtual bases are added at the end (a primary virtual base
3959 will have already been added). */
3960 if (BINFO_VIRTUAL_P (base_binfo))
3963 next_field = build_base_field (rli, base_binfo,
3964 offsets, next_field);
3968 /* Go through the TYPE_METHODS of T issuing any appropriate
3969 diagnostics, figuring out which methods override which other
3970 methods, and so forth. */
3973 check_methods (tree t)
3977 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
3979 check_for_override (x, t);
3980 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3981 error ("initializer specified for non-virtual method %q+D", x);
3982 /* The name of the field is the original field name
3983 Save this in auxiliary field for later overloading. */
3984 if (DECL_VINDEX (x))
3986 TYPE_POLYMORPHIC_P (t) = 1;
3987 if (DECL_PURE_VIRTUAL_P (x))
3988 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3990 /* All user-provided destructors are non-trivial.
3991 Constructors and assignment ops are handled in
3992 grok_special_member_properties. */
3993 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
3994 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3998 /* FN is a constructor or destructor. Clone the declaration to create
3999 a specialized in-charge or not-in-charge version, as indicated by
4003 build_clone (tree fn, tree name)
4008 /* Copy the function. */
4009 clone = copy_decl (fn);
4010 /* Reset the function name. */
4011 DECL_NAME (clone) = name;
4012 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
4013 /* Remember where this function came from. */
4014 DECL_ABSTRACT_ORIGIN (clone) = fn;
4015 /* Make it easy to find the CLONE given the FN. */
4016 DECL_CHAIN (clone) = DECL_CHAIN (fn);
4017 DECL_CHAIN (fn) = clone;
4019 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
4020 if (TREE_CODE (clone) == TEMPLATE_DECL)
4022 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
4023 DECL_TEMPLATE_RESULT (clone) = result;
4024 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
4025 DECL_TI_TEMPLATE (result) = clone;
4026 TREE_TYPE (clone) = TREE_TYPE (result);
4030 DECL_CLONED_FUNCTION (clone) = fn;
4031 /* There's no pending inline data for this function. */
4032 DECL_PENDING_INLINE_INFO (clone) = NULL;
4033 DECL_PENDING_INLINE_P (clone) = 0;
4035 /* The base-class destructor is not virtual. */
4036 if (name == base_dtor_identifier)
4038 DECL_VIRTUAL_P (clone) = 0;
4039 if (TREE_CODE (clone) != TEMPLATE_DECL)
4040 DECL_VINDEX (clone) = NULL_TREE;
4043 /* If there was an in-charge parameter, drop it from the function
4045 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4051 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4052 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4053 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
4054 /* Skip the `this' parameter. */
4055 parmtypes = TREE_CHAIN (parmtypes);
4056 /* Skip the in-charge parameter. */
4057 parmtypes = TREE_CHAIN (parmtypes);
4058 /* And the VTT parm, in a complete [cd]tor. */
4059 if (DECL_HAS_VTT_PARM_P (fn)
4060 && ! DECL_NEEDS_VTT_PARM_P (clone))
4061 parmtypes = TREE_CHAIN (parmtypes);
4062 /* If this is subobject constructor or destructor, add the vtt
4065 = build_method_type_directly (basetype,
4066 TREE_TYPE (TREE_TYPE (clone)),
4069 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
4072 = cp_build_type_attribute_variant (TREE_TYPE (clone),
4073 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
4076 /* Copy the function parameters. */
4077 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
4078 /* Remove the in-charge parameter. */
4079 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4081 DECL_CHAIN (DECL_ARGUMENTS (clone))
4082 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4083 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
4085 /* And the VTT parm, in a complete [cd]tor. */
4086 if (DECL_HAS_VTT_PARM_P (fn))
4088 if (DECL_NEEDS_VTT_PARM_P (clone))
4089 DECL_HAS_VTT_PARM_P (clone) = 1;
4092 DECL_CHAIN (DECL_ARGUMENTS (clone))
4093 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4094 DECL_HAS_VTT_PARM_P (clone) = 0;
4098 for (parms = DECL_ARGUMENTS (clone); parms; parms = DECL_CHAIN (parms))
4100 DECL_CONTEXT (parms) = clone;
4101 cxx_dup_lang_specific_decl (parms);
4104 /* Create the RTL for this function. */
4105 SET_DECL_RTL (clone, NULL);
4106 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
4109 note_decl_for_pch (clone);
4114 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4115 not invoke this function directly.
4117 For a non-thunk function, returns the address of the slot for storing
4118 the function it is a clone of. Otherwise returns NULL_TREE.
4120 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4121 cloned_function is unset. This is to support the separate
4122 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4123 on a template makes sense, but not the former. */
4126 decl_cloned_function_p (const_tree decl, bool just_testing)
4130 decl = STRIP_TEMPLATE (decl);
4132 if (TREE_CODE (decl) != FUNCTION_DECL
4133 || !DECL_LANG_SPECIFIC (decl)
4134 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
4136 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4138 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
4144 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
4145 if (just_testing && *ptr == NULL_TREE)
4151 /* Produce declarations for all appropriate clones of FN. If
4152 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4153 CLASTYPE_METHOD_VEC as well. */
4156 clone_function_decl (tree fn, int update_method_vec_p)
4160 /* Avoid inappropriate cloning. */
4162 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (fn)))
4165 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4167 /* For each constructor, we need two variants: an in-charge version
4168 and a not-in-charge version. */
4169 clone = build_clone (fn, complete_ctor_identifier);
4170 if (update_method_vec_p)
4171 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4172 clone = build_clone (fn, base_ctor_identifier);
4173 if (update_method_vec_p)
4174 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4178 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4180 /* For each destructor, we need three variants: an in-charge
4181 version, a not-in-charge version, and an in-charge deleting
4182 version. We clone the deleting version first because that
4183 means it will go second on the TYPE_METHODS list -- and that
4184 corresponds to the correct layout order in the virtual
4187 For a non-virtual destructor, we do not build a deleting
4189 if (DECL_VIRTUAL_P (fn))
4191 clone = build_clone (fn, deleting_dtor_identifier);
4192 if (update_method_vec_p)
4193 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4195 clone = build_clone (fn, complete_dtor_identifier);
4196 if (update_method_vec_p)
4197 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4198 clone = build_clone (fn, base_dtor_identifier);
4199 if (update_method_vec_p)
4200 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4203 /* Note that this is an abstract function that is never emitted. */
4204 DECL_ABSTRACT (fn) = 1;
4207 /* DECL is an in charge constructor, which is being defined. This will
4208 have had an in class declaration, from whence clones were
4209 declared. An out-of-class definition can specify additional default
4210 arguments. As it is the clones that are involved in overload
4211 resolution, we must propagate the information from the DECL to its
4215 adjust_clone_args (tree decl)
4219 for (clone = DECL_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4220 clone = DECL_CHAIN (clone))
4222 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4223 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4224 tree decl_parms, clone_parms;
4226 clone_parms = orig_clone_parms;
4228 /* Skip the 'this' parameter. */
4229 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4230 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4232 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4233 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4234 if (DECL_HAS_VTT_PARM_P (decl))
4235 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4237 clone_parms = orig_clone_parms;
4238 if (DECL_HAS_VTT_PARM_P (clone))
4239 clone_parms = TREE_CHAIN (clone_parms);
4241 for (decl_parms = orig_decl_parms; decl_parms;
4242 decl_parms = TREE_CHAIN (decl_parms),
4243 clone_parms = TREE_CHAIN (clone_parms))
4245 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4246 TREE_TYPE (clone_parms)));
4248 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4250 /* A default parameter has been added. Adjust the
4251 clone's parameters. */
4252 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4253 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4254 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4257 clone_parms = orig_decl_parms;
4259 if (DECL_HAS_VTT_PARM_P (clone))
4261 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4262 TREE_VALUE (orig_clone_parms),
4264 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4266 type = build_method_type_directly (basetype,
4267 TREE_TYPE (TREE_TYPE (clone)),
4270 type = build_exception_variant (type, exceptions);
4272 type = cp_build_type_attribute_variant (type, attrs);
4273 TREE_TYPE (clone) = type;
4275 clone_parms = NULL_TREE;
4279 gcc_assert (!clone_parms);
4283 /* For each of the constructors and destructors in T, create an
4284 in-charge and not-in-charge variant. */
4287 clone_constructors_and_destructors (tree t)
4291 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4293 if (!CLASSTYPE_METHOD_VEC (t))
4296 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4297 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4298 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4299 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4302 /* Subroutine of set_one_vmethod_tm_attributes. Search base classes
4303 of TYPE for virtual functions which FNDECL overrides. Return a
4304 mask of the tm attributes found therein. */
4307 look_for_tm_attr_overrides (tree type, tree fndecl)
4309 tree binfo = TYPE_BINFO (type);
4313 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ++ix)
4315 tree o, basetype = BINFO_TYPE (base_binfo);
4317 if (!TYPE_POLYMORPHIC_P (basetype))
4320 o = look_for_overrides_here (basetype, fndecl);
4322 found |= tm_attr_to_mask (find_tm_attribute
4323 (TYPE_ATTRIBUTES (TREE_TYPE (o))));
4325 found |= look_for_tm_attr_overrides (basetype, fndecl);
4331 /* Subroutine of set_method_tm_attributes. Handle the checks and
4332 inheritance for one virtual method FNDECL. */
4335 set_one_vmethod_tm_attributes (tree type, tree fndecl)
4340 found = look_for_tm_attr_overrides (type, fndecl);
4342 /* If FNDECL doesn't actually override anything (i.e. T is the
4343 class that first declares FNDECL virtual), then we're done. */
4347 tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (TREE_TYPE (fndecl)));
4348 have = tm_attr_to_mask (tm_attr);
4350 /* Intel STM Language Extension 3.0, Section 4.2 table 4:
4351 tm_pure must match exactly, otherwise no weakening of
4352 tm_safe > tm_callable > nothing. */
4353 /* ??? The tm_pure attribute didn't make the transition to the
4354 multivendor language spec. */
4355 if (have == TM_ATTR_PURE)
4357 if (found != TM_ATTR_PURE)
4363 /* If the overridden function is tm_pure, then FNDECL must be. */
4364 else if (found == TM_ATTR_PURE && tm_attr)
4366 /* Look for base class combinations that cannot be satisfied. */
4367 else if (found != TM_ATTR_PURE && (found & TM_ATTR_PURE))
4369 found &= ~TM_ATTR_PURE;
4371 error_at (DECL_SOURCE_LOCATION (fndecl),
4372 "method overrides both %<transaction_pure%> and %qE methods",
4373 tm_mask_to_attr (found));
4375 /* If FNDECL did not declare an attribute, then inherit the most
4377 else if (tm_attr == NULL)
4379 apply_tm_attr (fndecl, tm_mask_to_attr (found & -found));
4381 /* Otherwise validate that we're not weaker than a function
4382 that is being overridden. */
4386 if (found <= TM_ATTR_CALLABLE && have > found)
4392 error_at (DECL_SOURCE_LOCATION (fndecl),
4393 "method declared %qE overriding %qE method",
4394 tm_attr, tm_mask_to_attr (found));
4397 /* For each of the methods in T, propagate a class-level tm attribute. */
4400 set_method_tm_attributes (tree t)
4402 tree class_tm_attr, fndecl;
4404 /* Don't bother collecting tm attributes if transactional memory
4405 support is not enabled. */
4409 /* Process virtual methods first, as they inherit directly from the
4410 base virtual function and also require validation of new attributes. */
4411 if (TYPE_CONTAINS_VPTR_P (t))
4414 for (vchain = BINFO_VIRTUALS (TYPE_BINFO (t)); vchain;
4415 vchain = TREE_CHAIN (vchain))
4416 set_one_vmethod_tm_attributes (t, BV_FN (vchain));
4419 /* If the class doesn't have an attribute, nothing more to do. */
4420 class_tm_attr = find_tm_attribute (TYPE_ATTRIBUTES (t));
4421 if (class_tm_attr == NULL)
4424 /* Any method that does not yet have a tm attribute inherits
4425 the one from the class. */
4426 for (fndecl = TYPE_METHODS (t); fndecl; fndecl = TREE_CHAIN (fndecl))
4428 if (!find_tm_attribute (TYPE_ATTRIBUTES (TREE_TYPE (fndecl))))
4429 apply_tm_attr (fndecl, class_tm_attr);
4433 /* Returns true iff class T has a user-defined constructor other than
4434 the default constructor. */
4437 type_has_user_nondefault_constructor (tree t)
4441 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4444 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4446 tree fn = OVL_CURRENT (fns);
4447 if (!DECL_ARTIFICIAL (fn)
4448 && (TREE_CODE (fn) == TEMPLATE_DECL
4449 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4457 /* Returns the defaulted constructor if T has one. Otherwise, returns
4461 in_class_defaulted_default_constructor (tree t)
4465 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4468 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4470 tree fn = OVL_CURRENT (fns);
4472 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4474 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4475 while (args && TREE_PURPOSE (args))
4476 args = TREE_CHAIN (args);
4477 if (!args || args == void_list_node)
4485 /* Returns true iff FN is a user-provided function, i.e. user-declared
4486 and not defaulted at its first declaration; or explicit, private,
4487 protected, or non-const. */
4490 user_provided_p (tree fn)
4492 if (TREE_CODE (fn) == TEMPLATE_DECL)
4495 return (!DECL_ARTIFICIAL (fn)
4496 && !DECL_DEFAULTED_IN_CLASS_P (fn));
4499 /* Returns true iff class T has a user-provided constructor. */
4502 type_has_user_provided_constructor (tree t)
4506 if (!CLASS_TYPE_P (t))
4509 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4512 /* This can happen in error cases; avoid crashing. */
4513 if (!CLASSTYPE_METHOD_VEC (t))
4516 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4517 if (user_provided_p (OVL_CURRENT (fns)))
4523 /* Returns true iff class T has a user-provided default constructor. */
4526 type_has_user_provided_default_constructor (tree t)
4530 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4533 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4535 tree fn = OVL_CURRENT (fns);
4536 if (TREE_CODE (fn) == FUNCTION_DECL
4537 && user_provided_p (fn)
4538 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)))
4545 /* If default-initialization leaves part of TYPE uninitialized, returns
4546 a DECL for the field or TYPE itself (DR 253). */
4549 default_init_uninitialized_part (tree type)
4554 type = strip_array_types (type);
4555 if (!CLASS_TYPE_P (type))
4557 if (type_has_user_provided_default_constructor (type))
4559 for (binfo = TYPE_BINFO (type), i = 0;
4560 BINFO_BASE_ITERATE (binfo, i, t); ++i)
4562 r = default_init_uninitialized_part (BINFO_TYPE (t));
4566 for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t))
4567 if (TREE_CODE (t) == FIELD_DECL
4568 && !DECL_ARTIFICIAL (t)
4569 && !DECL_INITIAL (t))
4571 r = default_init_uninitialized_part (TREE_TYPE (t));
4573 return DECL_P (r) ? r : t;
4579 /* Returns true iff for class T, a trivial synthesized default constructor
4580 would be constexpr. */
4583 trivial_default_constructor_is_constexpr (tree t)
4585 /* A defaulted trivial default constructor is constexpr
4586 if there is nothing to initialize. */
4587 gcc_assert (!TYPE_HAS_COMPLEX_DFLT (t));
4588 return is_really_empty_class (t);
4591 /* Returns true iff class T has a constexpr default constructor. */
4594 type_has_constexpr_default_constructor (tree t)
4598 if (!CLASS_TYPE_P (t))
4600 /* The caller should have stripped an enclosing array. */
4601 gcc_assert (TREE_CODE (t) != ARRAY_TYPE);
4604 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t))
4606 if (!TYPE_HAS_COMPLEX_DFLT (t))
4607 return trivial_default_constructor_is_constexpr (t);
4608 /* Non-trivial, we need to check subobject constructors. */
4609 lazily_declare_fn (sfk_constructor, t);
4611 fns = locate_ctor (t);
4612 return (fns && DECL_DECLARED_CONSTEXPR_P (fns));
4615 /* Returns true iff class TYPE has a virtual destructor. */
4618 type_has_virtual_destructor (tree type)
4622 if (!CLASS_TYPE_P (type))
4625 gcc_assert (COMPLETE_TYPE_P (type));
4626 dtor = CLASSTYPE_DESTRUCTORS (type);
4627 return (dtor && DECL_VIRTUAL_P (dtor));
4630 /* Returns true iff class T has a move constructor. */
4633 type_has_move_constructor (tree t)
4637 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4639 gcc_assert (COMPLETE_TYPE_P (t));
4640 lazily_declare_fn (sfk_move_constructor, t);
4643 if (!CLASSTYPE_METHOD_VEC (t))
4646 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4647 if (move_fn_p (OVL_CURRENT (fns)))
4653 /* Returns true iff class T has a move assignment operator. */
4656 type_has_move_assign (tree t)
4660 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4662 gcc_assert (COMPLETE_TYPE_P (t));
4663 lazily_declare_fn (sfk_move_assignment, t);
4666 for (fns = lookup_fnfields_slot_nolazy (t, ansi_assopname (NOP_EXPR));
4667 fns; fns = OVL_NEXT (fns))
4668 if (move_fn_p (OVL_CURRENT (fns)))
4674 /* Returns true iff class T has a move constructor that was explicitly
4675 declared in the class body. Note that this is different from
4676 "user-provided", which doesn't include functions that are defaulted in
4680 type_has_user_declared_move_constructor (tree t)
4684 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4687 if (!CLASSTYPE_METHOD_VEC (t))
4690 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4692 tree fn = OVL_CURRENT (fns);
4693 if (move_fn_p (fn) && !DECL_ARTIFICIAL (fn))
4700 /* Returns true iff class T has a move assignment operator that was
4701 explicitly declared in the class body. */
4704 type_has_user_declared_move_assign (tree t)
4708 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4711 for (fns = lookup_fnfields_slot_nolazy (t, ansi_assopname (NOP_EXPR));
4712 fns; fns = OVL_NEXT (fns))
4714 tree fn = OVL_CURRENT (fns);
4715 if (move_fn_p (fn) && !DECL_ARTIFICIAL (fn))
4722 /* Nonzero if we need to build up a constructor call when initializing an
4723 object of this class, either because it has a user-provided constructor
4724 or because it doesn't have a default constructor (so we need to give an
4725 error if no initializer is provided). Use TYPE_NEEDS_CONSTRUCTING when
4726 what you care about is whether or not an object can be produced by a
4727 constructor (e.g. so we don't set TREE_READONLY on const variables of
4728 such type); use this function when what you care about is whether or not
4729 to try to call a constructor to create an object. The latter case is
4730 the former plus some cases of constructors that cannot be called. */
4733 type_build_ctor_call (tree t)
4736 if (TYPE_NEEDS_CONSTRUCTING (t))
4738 inner = strip_array_types (t);
4739 return (CLASS_TYPE_P (inner) && !TYPE_HAS_DEFAULT_CONSTRUCTOR (inner)
4740 && !ANON_AGGR_TYPE_P (inner));
4743 /* Remove all zero-width bit-fields from T. */
4746 remove_zero_width_bit_fields (tree t)
4750 fieldsp = &TYPE_FIELDS (t);
4753 if (TREE_CODE (*fieldsp) == FIELD_DECL
4754 && DECL_C_BIT_FIELD (*fieldsp)
4755 /* We should not be confused by the fact that grokbitfield
4756 temporarily sets the width of the bit field into
4757 DECL_INITIAL (*fieldsp).
4758 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4760 && integer_zerop (DECL_SIZE (*fieldsp)))
4761 *fieldsp = DECL_CHAIN (*fieldsp);
4763 fieldsp = &DECL_CHAIN (*fieldsp);
4767 /* Returns TRUE iff we need a cookie when dynamically allocating an
4768 array whose elements have the indicated class TYPE. */
4771 type_requires_array_cookie (tree type)
4774 bool has_two_argument_delete_p = false;
4776 gcc_assert (CLASS_TYPE_P (type));
4778 /* If there's a non-trivial destructor, we need a cookie. In order
4779 to iterate through the array calling the destructor for each
4780 element, we'll have to know how many elements there are. */
4781 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4784 /* If the usual deallocation function is a two-argument whose second
4785 argument is of type `size_t', then we have to pass the size of
4786 the array to the deallocation function, so we will need to store
4788 fns = lookup_fnfields (TYPE_BINFO (type),
4789 ansi_opname (VEC_DELETE_EXPR),
4791 /* If there are no `operator []' members, or the lookup is
4792 ambiguous, then we don't need a cookie. */
4793 if (!fns || fns == error_mark_node)
4795 /* Loop through all of the functions. */
4796 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4801 /* Select the current function. */
4802 fn = OVL_CURRENT (fns);
4803 /* See if this function is a one-argument delete function. If
4804 it is, then it will be the usual deallocation function. */
4805 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4806 if (second_parm == void_list_node)
4808 /* Do not consider this function if its second argument is an
4812 /* Otherwise, if we have a two-argument function and the second
4813 argument is `size_t', it will be the usual deallocation
4814 function -- unless there is one-argument function, too. */
4815 if (TREE_CHAIN (second_parm) == void_list_node
4816 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4817 has_two_argument_delete_p = true;
4820 return has_two_argument_delete_p;
4823 /* Finish computing the `literal type' property of class type T.
4825 At this point, we have already processed base classes and
4826 non-static data members. We need to check whether the copy
4827 constructor is trivial, the destructor is trivial, and there
4828 is a trivial default constructor or at least one constexpr
4829 constructor other than the copy constructor. */
4832 finalize_literal_type_property (tree t)
4836 if (cxx_dialect < cxx0x
4837 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
4838 CLASSTYPE_LITERAL_P (t) = false;
4839 else if (CLASSTYPE_LITERAL_P (t) && !TYPE_HAS_TRIVIAL_DFLT (t)
4840 && CLASSTYPE_NON_AGGREGATE (t)
4841 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4842 CLASSTYPE_LITERAL_P (t) = false;
4844 if (!CLASSTYPE_LITERAL_P (t))
4845 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4846 if (DECL_DECLARED_CONSTEXPR_P (fn)
4847 && TREE_CODE (fn) != TEMPLATE_DECL
4848 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
4849 && !DECL_CONSTRUCTOR_P (fn))
4851 DECL_DECLARED_CONSTEXPR_P (fn) = false;
4852 if (!DECL_GENERATED_P (fn))
4854 error ("enclosing class of constexpr non-static member "
4855 "function %q+#D is not a literal type", fn);
4856 explain_non_literal_class (t);
4861 /* T is a non-literal type used in a context which requires a constant
4862 expression. Explain why it isn't literal. */
4865 explain_non_literal_class (tree t)
4867 static struct pointer_set_t *diagnosed;
4869 if (!CLASS_TYPE_P (t))
4871 t = TYPE_MAIN_VARIANT (t);
4873 if (diagnosed == NULL)
4874 diagnosed = pointer_set_create ();
4875 if (pointer_set_insert (diagnosed, t) != 0)
4876 /* Already explained. */
4879 inform (0, "%q+T is not literal because:", t);
4880 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
4881 inform (0, " %q+T has a non-trivial destructor", t);
4882 else if (CLASSTYPE_NON_AGGREGATE (t)
4883 && !TYPE_HAS_TRIVIAL_DFLT (t)
4884 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4886 inform (0, " %q+T is not an aggregate, does not have a trivial "
4887 "default constructor, and has no constexpr constructor that "
4888 "is not a copy or move constructor", t);
4889 if (TYPE_HAS_DEFAULT_CONSTRUCTOR (t)
4890 && !type_has_user_provided_default_constructor (t))
4891 explain_invalid_constexpr_fn (locate_ctor (t));
4895 tree binfo, base_binfo, field; int i;
4896 for (binfo = TYPE_BINFO (t), i = 0;
4897 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
4899 tree basetype = TREE_TYPE (base_binfo);
4900 if (!CLASSTYPE_LITERAL_P (basetype))
4902 inform (0, " base class %qT of %q+T is non-literal",
4904 explain_non_literal_class (basetype);
4908 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4911 if (TREE_CODE (field) != FIELD_DECL)
4913 ftype = TREE_TYPE (field);
4914 if (!literal_type_p (ftype))
4916 inform (0, " non-static data member %q+D has "
4917 "non-literal type", field);
4918 if (CLASS_TYPE_P (ftype))
4919 explain_non_literal_class (ftype);
4925 /* Check the validity of the bases and members declared in T. Add any
4926 implicitly-generated functions (like copy-constructors and
4927 assignment operators). Compute various flag bits (like
4928 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4929 level: i.e., independently of the ABI in use. */
4932 check_bases_and_members (tree t)
4934 /* Nonzero if the implicitly generated copy constructor should take
4935 a non-const reference argument. */
4936 int cant_have_const_ctor;
4937 /* Nonzero if the implicitly generated assignment operator
4938 should take a non-const reference argument. */
4939 int no_const_asn_ref;
4941 bool saved_complex_asn_ref;
4942 bool saved_nontrivial_dtor;
4945 /* By default, we use const reference arguments and generate default
4947 cant_have_const_ctor = 0;
4948 no_const_asn_ref = 0;
4950 /* Check all the base-classes. */
4951 check_bases (t, &cant_have_const_ctor,
4954 /* Check all the method declarations. */
4957 /* Save the initial values of these flags which only indicate whether
4958 or not the class has user-provided functions. As we analyze the
4959 bases and members we can set these flags for other reasons. */
4960 saved_complex_asn_ref = TYPE_HAS_COMPLEX_COPY_ASSIGN (t);
4961 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4963 /* Check all the data member declarations. We cannot call
4964 check_field_decls until we have called check_bases check_methods,
4965 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4966 being set appropriately. */
4967 check_field_decls (t, &access_decls,
4968 &cant_have_const_ctor,
4971 /* A nearly-empty class has to be vptr-containing; a nearly empty
4972 class contains just a vptr. */
4973 if (!TYPE_CONTAINS_VPTR_P (t))
4974 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4976 /* Do some bookkeeping that will guide the generation of implicitly
4977 declared member functions. */
4978 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4979 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4980 /* We need to call a constructor for this class if it has a
4981 user-provided constructor, or if the default constructor is going
4982 to initialize the vptr. (This is not an if-and-only-if;
4983 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4984 themselves need constructing.) */
4985 TYPE_NEEDS_CONSTRUCTING (t)
4986 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4989 An aggregate is an array or a class with no user-provided
4990 constructors ... and no virtual functions.
4992 Again, other conditions for being an aggregate are checked
4994 CLASSTYPE_NON_AGGREGATE (t)
4995 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4996 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4997 retain the old definition internally for ABI reasons. */
4998 CLASSTYPE_NON_LAYOUT_POD_P (t)
4999 |= (CLASSTYPE_NON_AGGREGATE (t)
5000 || saved_nontrivial_dtor || saved_complex_asn_ref);
5001 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
5002 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
5003 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
5004 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
5006 /* If the class has no user-declared constructor, but does have
5007 non-static const or reference data members that can never be
5008 initialized, issue a warning. */
5009 if (warn_uninitialized
5010 /* Classes with user-declared constructors are presumed to
5011 initialize these members. */
5012 && !TYPE_HAS_USER_CONSTRUCTOR (t)
5013 /* Aggregates can be initialized with brace-enclosed
5015 && CLASSTYPE_NON_AGGREGATE (t))
5019 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5023 if (TREE_CODE (field) != FIELD_DECL)
5026 type = TREE_TYPE (field);
5027 if (TREE_CODE (type) == REFERENCE_TYPE)
5028 warning (OPT_Wuninitialized, "non-static reference %q+#D "
5029 "in class without a constructor", field);
5030 else if (CP_TYPE_CONST_P (type)
5031 && (!CLASS_TYPE_P (type)
5032 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
5033 warning (OPT_Wuninitialized, "non-static const member %q+#D "
5034 "in class without a constructor", field);
5038 /* Synthesize any needed methods. */
5039 add_implicitly_declared_members (t,
5040 cant_have_const_ctor,
5043 /* Check defaulted declarations here so we have cant_have_const_ctor
5044 and don't need to worry about clones. */
5045 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
5046 if (DECL_DEFAULTED_IN_CLASS_P (fn))
5048 int copy = copy_fn_p (fn);
5052 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
5053 : !no_const_asn_ref);
5054 bool fn_const_p = (copy == 2);
5056 if (fn_const_p && !imp_const_p)
5057 /* If the function is defaulted outside the class, we just
5058 give the synthesis error. */
5059 error ("%q+D declared to take const reference, but implicit "
5060 "declaration would take non-const", fn);
5061 else if (imp_const_p && !fn_const_p)
5062 error ("%q+D declared to take non-const reference cannot be "
5063 "defaulted in the class body", fn);
5065 defaulted_late_check (fn);
5068 if (LAMBDA_TYPE_P (t))
5070 /* "The closure type associated with a lambda-expression has a deleted
5071 default constructor and a deleted copy assignment operator." */
5072 TYPE_NEEDS_CONSTRUCTING (t) = 1;
5073 TYPE_HAS_COMPLEX_DFLT (t) = 1;
5074 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
5075 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 0;
5077 /* "This class type is not an aggregate." */
5078 CLASSTYPE_NON_AGGREGATE (t) = 1;
5081 /* Compute the 'literal type' property before we
5082 do anything with non-static member functions. */
5083 finalize_literal_type_property (t);
5085 /* Create the in-charge and not-in-charge variants of constructors
5087 clone_constructors_and_destructors (t);
5089 /* Process the using-declarations. */
5090 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
5091 handle_using_decl (TREE_VALUE (access_decls), t);
5093 /* Build and sort the CLASSTYPE_METHOD_VEC. */
5094 finish_struct_methods (t);
5096 /* Figure out whether or not we will need a cookie when dynamically
5097 allocating an array of this type. */
5098 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
5099 = type_requires_array_cookie (t);
5102 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
5103 accordingly. If a new vfield was created (because T doesn't have a
5104 primary base class), then the newly created field is returned. It
5105 is not added to the TYPE_FIELDS list; it is the caller's
5106 responsibility to do that. Accumulate declared virtual functions
5110 create_vtable_ptr (tree t, tree* virtuals_p)
5114 /* Collect the virtual functions declared in T. */
5115 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
5116 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
5117 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
5119 tree new_virtual = make_node (TREE_LIST);
5121 BV_FN (new_virtual) = fn;
5122 BV_DELTA (new_virtual) = integer_zero_node;
5123 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
5125 TREE_CHAIN (new_virtual) = *virtuals_p;
5126 *virtuals_p = new_virtual;
5129 /* If we couldn't find an appropriate base class, create a new field
5130 here. Even if there weren't any new virtual functions, we might need a
5131 new virtual function table if we're supposed to include vptrs in
5132 all classes that need them. */
5133 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
5135 /* We build this decl with vtbl_ptr_type_node, which is a
5136 `vtable_entry_type*'. It might seem more precise to use
5137 `vtable_entry_type (*)[N]' where N is the number of virtual
5138 functions. However, that would require the vtable pointer in
5139 base classes to have a different type than the vtable pointer
5140 in derived classes. We could make that happen, but that
5141 still wouldn't solve all the problems. In particular, the
5142 type-based alias analysis code would decide that assignments
5143 to the base class vtable pointer can't alias assignments to
5144 the derived class vtable pointer, since they have different
5145 types. Thus, in a derived class destructor, where the base
5146 class constructor was inlined, we could generate bad code for
5147 setting up the vtable pointer.
5149 Therefore, we use one type for all vtable pointers. We still
5150 use a type-correct type; it's just doesn't indicate the array
5151 bounds. That's better than using `void*' or some such; it's
5152 cleaner, and it let's the alias analysis code know that these
5153 stores cannot alias stores to void*! */
5156 field = build_decl (input_location,
5157 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
5158 DECL_VIRTUAL_P (field) = 1;
5159 DECL_ARTIFICIAL (field) = 1;
5160 DECL_FIELD_CONTEXT (field) = t;
5161 DECL_FCONTEXT (field) = t;
5162 if (TYPE_PACKED (t))
5163 DECL_PACKED (field) = 1;
5165 TYPE_VFIELD (t) = field;
5167 /* This class is non-empty. */
5168 CLASSTYPE_EMPTY_P (t) = 0;
5176 /* Add OFFSET to all base types of BINFO which is a base in the
5177 hierarchy dominated by T.
5179 OFFSET, which is a type offset, is number of bytes. */
5182 propagate_binfo_offsets (tree binfo, tree offset)
5188 /* Update BINFO's offset. */
5189 BINFO_OFFSET (binfo)
5190 = convert (sizetype,
5191 size_binop (PLUS_EXPR,
5192 convert (ssizetype, BINFO_OFFSET (binfo)),
5195 /* Find the primary base class. */
5196 primary_binfo = get_primary_binfo (binfo);
5198 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
5199 propagate_binfo_offsets (primary_binfo, offset);
5201 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
5203 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5205 /* Don't do the primary base twice. */
5206 if (base_binfo == primary_binfo)
5209 if (BINFO_VIRTUAL_P (base_binfo))
5212 propagate_binfo_offsets (base_binfo, offset);
5216 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
5217 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
5218 empty subobjects of T. */
5221 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
5225 bool first_vbase = true;
5228 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
5231 if (!abi_version_at_least(2))
5233 /* In G++ 3.2, we incorrectly rounded the size before laying out
5234 the virtual bases. */
5235 finish_record_layout (rli, /*free_p=*/false);
5236 #ifdef STRUCTURE_SIZE_BOUNDARY
5237 /* Packed structures don't need to have minimum size. */
5238 if (! TYPE_PACKED (t))
5239 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
5241 rli->offset = TYPE_SIZE_UNIT (t);
5242 rli->bitpos = bitsize_zero_node;
5243 rli->record_align = TYPE_ALIGN (t);
5246 /* Find the last field. The artificial fields created for virtual
5247 bases will go after the last extant field to date. */
5248 next_field = &TYPE_FIELDS (t);
5250 next_field = &DECL_CHAIN (*next_field);
5252 /* Go through the virtual bases, allocating space for each virtual
5253 base that is not already a primary base class. These are
5254 allocated in inheritance graph order. */
5255 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
5257 if (!BINFO_VIRTUAL_P (vbase))
5260 if (!BINFO_PRIMARY_P (vbase))
5262 tree basetype = TREE_TYPE (vbase);
5264 /* This virtual base is not a primary base of any class in the
5265 hierarchy, so we have to add space for it. */
5266 next_field = build_base_field (rli, vbase,
5267 offsets, next_field);
5269 /* If the first virtual base might have been placed at a
5270 lower address, had we started from CLASSTYPE_SIZE, rather
5271 than TYPE_SIZE, issue a warning. There can be both false
5272 positives and false negatives from this warning in rare
5273 cases; to deal with all the possibilities would probably
5274 require performing both layout algorithms and comparing
5275 the results which is not particularly tractable. */
5279 (size_binop (CEIL_DIV_EXPR,
5280 round_up_loc (input_location,
5282 CLASSTYPE_ALIGN (basetype)),
5284 BINFO_OFFSET (vbase))))
5286 "offset of virtual base %qT is not ABI-compliant and "
5287 "may change in a future version of GCC",
5290 first_vbase = false;
5295 /* Returns the offset of the byte just past the end of the base class
5299 end_of_base (tree binfo)
5303 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
5304 size = TYPE_SIZE_UNIT (char_type_node);
5305 else if (is_empty_class (BINFO_TYPE (binfo)))
5306 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
5307 allocate some space for it. It cannot have virtual bases, so
5308 TYPE_SIZE_UNIT is fine. */
5309 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5311 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5313 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
5316 /* Returns the offset of the byte just past the end of the base class
5317 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
5318 only non-virtual bases are included. */
5321 end_of_class (tree t, int include_virtuals_p)
5323 tree result = size_zero_node;
5324 VEC(tree,gc) *vbases;
5330 for (binfo = TYPE_BINFO (t), i = 0;
5331 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5333 if (!include_virtuals_p
5334 && BINFO_VIRTUAL_P (base_binfo)
5335 && (!BINFO_PRIMARY_P (base_binfo)
5336 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
5339 offset = end_of_base (base_binfo);
5340 if (INT_CST_LT_UNSIGNED (result, offset))
5344 /* G++ 3.2 did not check indirect virtual bases. */
5345 if (abi_version_at_least (2) && include_virtuals_p)
5346 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5347 VEC_iterate (tree, vbases, i, base_binfo); i++)
5349 offset = end_of_base (base_binfo);
5350 if (INT_CST_LT_UNSIGNED (result, offset))
5357 /* Warn about bases of T that are inaccessible because they are
5358 ambiguous. For example:
5361 struct T : public S {};
5362 struct U : public S, public T {};
5364 Here, `(S*) new U' is not allowed because there are two `S'
5368 warn_about_ambiguous_bases (tree t)
5371 VEC(tree,gc) *vbases;
5376 /* If there are no repeated bases, nothing can be ambiguous. */
5377 if (!CLASSTYPE_REPEATED_BASE_P (t))
5380 /* Check direct bases. */
5381 for (binfo = TYPE_BINFO (t), i = 0;
5382 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5384 basetype = BINFO_TYPE (base_binfo);
5386 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5387 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
5391 /* Check for ambiguous virtual bases. */
5393 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5394 VEC_iterate (tree, vbases, i, binfo); i++)
5396 basetype = BINFO_TYPE (binfo);
5398 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5399 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
5404 /* Compare two INTEGER_CSTs K1 and K2. */
5407 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
5409 return tree_int_cst_compare ((tree) k1, (tree) k2);
5412 /* Increase the size indicated in RLI to account for empty classes
5413 that are "off the end" of the class. */
5416 include_empty_classes (record_layout_info rli)
5421 /* It might be the case that we grew the class to allocate a
5422 zero-sized base class. That won't be reflected in RLI, yet,
5423 because we are willing to overlay multiple bases at the same
5424 offset. However, now we need to make sure that RLI is big enough
5425 to reflect the entire class. */
5426 eoc = end_of_class (rli->t,
5427 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
5428 rli_size = rli_size_unit_so_far (rli);
5429 if (TREE_CODE (rli_size) == INTEGER_CST
5430 && INT_CST_LT_UNSIGNED (rli_size, eoc))
5432 if (!abi_version_at_least (2))
5433 /* In version 1 of the ABI, the size of a class that ends with
5434 a bitfield was not rounded up to a whole multiple of a
5435 byte. Because rli_size_unit_so_far returns only the number
5436 of fully allocated bytes, any extra bits were not included
5438 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
5440 /* The size should have been rounded to a whole byte. */
5441 gcc_assert (tree_int_cst_equal
5442 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
5444 = size_binop (PLUS_EXPR,
5446 size_binop (MULT_EXPR,
5447 convert (bitsizetype,
5448 size_binop (MINUS_EXPR,
5450 bitsize_int (BITS_PER_UNIT)));
5451 normalize_rli (rli);
5455 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
5456 BINFO_OFFSETs for all of the base-classes. Position the vtable
5457 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
5460 layout_class_type (tree t, tree *virtuals_p)
5462 tree non_static_data_members;
5465 record_layout_info rli;
5466 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
5467 types that appear at that offset. */
5468 splay_tree empty_base_offsets;
5469 /* True if the last field layed out was a bit-field. */
5470 bool last_field_was_bitfield = false;
5471 /* The location at which the next field should be inserted. */
5473 /* T, as a base class. */
5476 /* Keep track of the first non-static data member. */
5477 non_static_data_members = TYPE_FIELDS (t);
5479 /* Start laying out the record. */
5480 rli = start_record_layout (t);
5482 /* Mark all the primary bases in the hierarchy. */
5483 determine_primary_bases (t);
5485 /* Create a pointer to our virtual function table. */
5486 vptr = create_vtable_ptr (t, virtuals_p);
5488 /* The vptr is always the first thing in the class. */
5491 DECL_CHAIN (vptr) = TYPE_FIELDS (t);
5492 TYPE_FIELDS (t) = vptr;
5493 next_field = &DECL_CHAIN (vptr);
5494 place_field (rli, vptr);
5497 next_field = &TYPE_FIELDS (t);
5499 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5500 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
5502 build_base_fields (rli, empty_base_offsets, next_field);
5504 /* Layout the non-static data members. */
5505 for (field = non_static_data_members; field; field = DECL_CHAIN (field))
5510 /* We still pass things that aren't non-static data members to
5511 the back end, in case it wants to do something with them. */
5512 if (TREE_CODE (field) != FIELD_DECL)
5514 place_field (rli, field);
5515 /* If the static data member has incomplete type, keep track
5516 of it so that it can be completed later. (The handling
5517 of pending statics in finish_record_layout is
5518 insufficient; consider:
5521 struct S2 { static S1 s1; };
5523 At this point, finish_record_layout will be called, but
5524 S1 is still incomplete.) */
5525 if (TREE_CODE (field) == VAR_DECL)
5527 maybe_register_incomplete_var (field);
5528 /* The visibility of static data members is determined
5529 at their point of declaration, not their point of
5531 determine_visibility (field);
5536 type = TREE_TYPE (field);
5537 if (type == error_mark_node)
5540 padding = NULL_TREE;
5542 /* If this field is a bit-field whose width is greater than its
5543 type, then there are some special rules for allocating
5545 if (DECL_C_BIT_FIELD (field)
5546 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
5550 bool was_unnamed_p = false;
5551 /* We must allocate the bits as if suitably aligned for the
5552 longest integer type that fits in this many bits. type
5553 of the field. Then, we are supposed to use the left over
5554 bits as additional padding. */
5555 for (itk = itk_char; itk != itk_none; ++itk)
5556 if (integer_types[itk] != NULL_TREE
5557 && (INT_CST_LT (size_int (MAX_FIXED_MODE_SIZE),
5558 TYPE_SIZE (integer_types[itk]))
5559 || INT_CST_LT (DECL_SIZE (field),
5560 TYPE_SIZE (integer_types[itk]))))
5563 /* ITK now indicates a type that is too large for the
5564 field. We have to back up by one to find the largest
5569 integer_type = integer_types[itk];
5570 } while (itk > 0 && integer_type == NULL_TREE);
5572 /* Figure out how much additional padding is required. GCC
5573 3.2 always created a padding field, even if it had zero
5575 if (!abi_version_at_least (2)
5576 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
5578 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
5579 /* In a union, the padding field must have the full width
5580 of the bit-field; all fields start at offset zero. */
5581 padding = DECL_SIZE (field);
5584 if (TREE_CODE (t) == UNION_TYPE)
5585 warning (OPT_Wabi, "size assigned to %qT may not be "
5586 "ABI-compliant and may change in a future "
5589 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
5590 TYPE_SIZE (integer_type));
5593 #ifdef PCC_BITFIELD_TYPE_MATTERS
5594 /* An unnamed bitfield does not normally affect the
5595 alignment of the containing class on a target where
5596 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5597 make any exceptions for unnamed bitfields when the
5598 bitfields are longer than their types. Therefore, we
5599 temporarily give the field a name. */
5600 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
5602 was_unnamed_p = true;
5603 DECL_NAME (field) = make_anon_name ();
5606 DECL_SIZE (field) = TYPE_SIZE (integer_type);
5607 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
5608 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
5609 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5610 empty_base_offsets);
5612 DECL_NAME (field) = NULL_TREE;
5613 /* Now that layout has been performed, set the size of the
5614 field to the size of its declared type; the rest of the
5615 field is effectively invisible. */
5616 DECL_SIZE (field) = TYPE_SIZE (type);
5617 /* We must also reset the DECL_MODE of the field. */
5618 if (abi_version_at_least (2))
5619 DECL_MODE (field) = TYPE_MODE (type);
5621 && DECL_MODE (field) != TYPE_MODE (type))
5622 /* Versions of G++ before G++ 3.4 did not reset the
5625 "the offset of %qD may not be ABI-compliant and may "
5626 "change in a future version of GCC", field);
5629 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5630 empty_base_offsets);
5632 /* Remember the location of any empty classes in FIELD. */
5633 if (abi_version_at_least (2))
5634 record_subobject_offsets (TREE_TYPE (field),
5635 byte_position(field),
5637 /*is_data_member=*/true);
5639 /* If a bit-field does not immediately follow another bit-field,
5640 and yet it starts in the middle of a byte, we have failed to
5641 comply with the ABI. */
5643 && DECL_C_BIT_FIELD (field)
5644 /* The TREE_NO_WARNING flag gets set by Objective-C when
5645 laying out an Objective-C class. The ObjC ABI differs
5646 from the C++ ABI, and so we do not want a warning
5648 && !TREE_NO_WARNING (field)
5649 && !last_field_was_bitfield
5650 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5651 DECL_FIELD_BIT_OFFSET (field),
5652 bitsize_unit_node)))
5653 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5654 "change in a future version of GCC", field);
5656 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5657 offset of the field. */
5659 && !abi_version_at_least (2)
5660 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5661 byte_position (field))
5662 && contains_empty_class_p (TREE_TYPE (field)))
5663 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5664 "classes to be placed at different locations in a "
5665 "future version of GCC", field);
5667 /* The middle end uses the type of expressions to determine the
5668 possible range of expression values. In order to optimize
5669 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5670 must be made aware of the width of "i", via its type.
5672 Because C++ does not have integer types of arbitrary width,
5673 we must (for the purposes of the front end) convert from the
5674 type assigned here to the declared type of the bitfield
5675 whenever a bitfield expression is used as an rvalue.
5676 Similarly, when assigning a value to a bitfield, the value
5677 must be converted to the type given the bitfield here. */
5678 if (DECL_C_BIT_FIELD (field))
5680 unsigned HOST_WIDE_INT width;
5681 tree ftype = TREE_TYPE (field);
5682 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5683 if (width != TYPE_PRECISION (ftype))
5686 = c_build_bitfield_integer_type (width,
5687 TYPE_UNSIGNED (ftype));
5689 = cp_build_qualified_type (TREE_TYPE (field),
5690 cp_type_quals (ftype));
5694 /* If we needed additional padding after this field, add it
5700 padding_field = build_decl (input_location,
5704 DECL_BIT_FIELD (padding_field) = 1;
5705 DECL_SIZE (padding_field) = padding;
5706 DECL_CONTEXT (padding_field) = t;
5707 DECL_ARTIFICIAL (padding_field) = 1;
5708 DECL_IGNORED_P (padding_field) = 1;
5709 layout_nonempty_base_or_field (rli, padding_field,
5711 empty_base_offsets);
5714 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5717 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5719 /* Make sure that we are on a byte boundary so that the size of
5720 the class without virtual bases will always be a round number
5722 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5723 normalize_rli (rli);
5726 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5728 if (!abi_version_at_least (2))
5729 include_empty_classes(rli);
5731 /* Delete all zero-width bit-fields from the list of fields. Now
5732 that the type is laid out they are no longer important. */
5733 remove_zero_width_bit_fields (t);
5735 /* Create the version of T used for virtual bases. We do not use
5736 make_class_type for this version; this is an artificial type. For
5737 a POD type, we just reuse T. */
5738 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5740 base_t = make_node (TREE_CODE (t));
5742 /* Set the size and alignment for the new type. In G++ 3.2, all
5743 empty classes were considered to have size zero when used as
5745 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5747 TYPE_SIZE (base_t) = bitsize_zero_node;
5748 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5749 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5751 "layout of classes derived from empty class %qT "
5752 "may change in a future version of GCC",
5759 /* If the ABI version is not at least two, and the last
5760 field was a bit-field, RLI may not be on a byte
5761 boundary. In particular, rli_size_unit_so_far might
5762 indicate the last complete byte, while rli_size_so_far
5763 indicates the total number of bits used. Therefore,
5764 rli_size_so_far, rather than rli_size_unit_so_far, is
5765 used to compute TYPE_SIZE_UNIT. */
5766 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5767 TYPE_SIZE_UNIT (base_t)
5768 = size_binop (MAX_EXPR,
5770 size_binop (CEIL_DIV_EXPR,
5771 rli_size_so_far (rli),
5772 bitsize_int (BITS_PER_UNIT))),
5775 = size_binop (MAX_EXPR,
5776 rli_size_so_far (rli),
5777 size_binop (MULT_EXPR,
5778 convert (bitsizetype, eoc),
5779 bitsize_int (BITS_PER_UNIT)));
5781 TYPE_ALIGN (base_t) = rli->record_align;
5782 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5784 /* Copy the fields from T. */
5785 next_field = &TYPE_FIELDS (base_t);
5786 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5787 if (TREE_CODE (field) == FIELD_DECL)
5789 *next_field = build_decl (input_location,
5793 DECL_CONTEXT (*next_field) = base_t;
5794 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5795 DECL_FIELD_BIT_OFFSET (*next_field)
5796 = DECL_FIELD_BIT_OFFSET (field);
5797 DECL_SIZE (*next_field) = DECL_SIZE (field);
5798 DECL_MODE (*next_field) = DECL_MODE (field);
5799 next_field = &DECL_CHAIN (*next_field);
5802 /* Record the base version of the type. */
5803 CLASSTYPE_AS_BASE (t) = base_t;
5804 TYPE_CONTEXT (base_t) = t;
5807 CLASSTYPE_AS_BASE (t) = t;
5809 /* Every empty class contains an empty class. */
5810 if (CLASSTYPE_EMPTY_P (t))
5811 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5813 /* Set the TYPE_DECL for this type to contain the right
5814 value for DECL_OFFSET, so that we can use it as part
5815 of a COMPONENT_REF for multiple inheritance. */
5816 layout_decl (TYPE_MAIN_DECL (t), 0);
5818 /* Now fix up any virtual base class types that we left lying
5819 around. We must get these done before we try to lay out the
5820 virtual function table. As a side-effect, this will remove the
5821 base subobject fields. */
5822 layout_virtual_bases (rli, empty_base_offsets);
5824 /* Make sure that empty classes are reflected in RLI at this
5826 include_empty_classes(rli);
5828 /* Make sure not to create any structures with zero size. */
5829 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5831 build_decl (input_location,
5832 FIELD_DECL, NULL_TREE, char_type_node));
5834 /* If this is a non-POD, declaring it packed makes a difference to how it
5835 can be used as a field; don't let finalize_record_size undo it. */
5836 if (TYPE_PACKED (t) && !layout_pod_type_p (t))
5837 rli->packed_maybe_necessary = true;
5839 /* Let the back end lay out the type. */
5840 finish_record_layout (rli, /*free_p=*/true);
5842 /* Warn about bases that can't be talked about due to ambiguity. */
5843 warn_about_ambiguous_bases (t);
5845 /* Now that we're done with layout, give the base fields the real types. */
5846 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5847 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5848 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5851 splay_tree_delete (empty_base_offsets);
5853 if (CLASSTYPE_EMPTY_P (t)
5854 && tree_int_cst_lt (sizeof_biggest_empty_class,
5855 TYPE_SIZE_UNIT (t)))
5856 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5859 /* Determine the "key method" for the class type indicated by TYPE,
5860 and set CLASSTYPE_KEY_METHOD accordingly. */
5863 determine_key_method (tree type)
5867 if (TYPE_FOR_JAVA (type)
5868 || processing_template_decl
5869 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5870 || CLASSTYPE_INTERFACE_KNOWN (type))
5873 /* The key method is the first non-pure virtual function that is not
5874 inline at the point of class definition. On some targets the
5875 key function may not be inline; those targets should not call
5876 this function until the end of the translation unit. */
5877 for (method = TYPE_METHODS (type); method != NULL_TREE;
5878 method = DECL_CHAIN (method))
5879 if (DECL_VINDEX (method) != NULL_TREE
5880 && ! DECL_DECLARED_INLINE_P (method)
5881 && ! DECL_PURE_VIRTUAL_P (method))
5883 CLASSTYPE_KEY_METHOD (type) = method;
5891 /* Allocate and return an instance of struct sorted_fields_type with
5894 static struct sorted_fields_type *
5895 sorted_fields_type_new (int n)
5897 struct sorted_fields_type *sft;
5898 sft = ggc_alloc_sorted_fields_type (sizeof (struct sorted_fields_type)
5899 + n * sizeof (tree));
5906 /* Perform processing required when the definition of T (a class type)
5910 finish_struct_1 (tree t)
5913 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5914 tree virtuals = NULL_TREE;
5917 if (COMPLETE_TYPE_P (t))
5919 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5920 error ("redefinition of %q#T", t);
5925 /* If this type was previously laid out as a forward reference,
5926 make sure we lay it out again. */
5927 TYPE_SIZE (t) = NULL_TREE;
5928 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5930 /* Make assumptions about the class; we'll reset the flags if
5932 CLASSTYPE_EMPTY_P (t) = 1;
5933 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5934 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5935 CLASSTYPE_LITERAL_P (t) = true;
5937 /* Do end-of-class semantic processing: checking the validity of the
5938 bases and members and add implicitly generated methods. */
5939 check_bases_and_members (t);
5941 /* Find the key method. */
5942 if (TYPE_CONTAINS_VPTR_P (t))
5944 /* The Itanium C++ ABI permits the key method to be chosen when
5945 the class is defined -- even though the key method so
5946 selected may later turn out to be an inline function. On
5947 some systems (such as ARM Symbian OS) the key method cannot
5948 be determined until the end of the translation unit. On such
5949 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5950 will cause the class to be added to KEYED_CLASSES. Then, in
5951 finish_file we will determine the key method. */
5952 if (targetm.cxx.key_method_may_be_inline ())
5953 determine_key_method (t);
5955 /* If a polymorphic class has no key method, we may emit the vtable
5956 in every translation unit where the class definition appears. */
5957 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5958 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5961 /* Layout the class itself. */
5962 layout_class_type (t, &virtuals);
5963 if (CLASSTYPE_AS_BASE (t) != t)
5964 /* We use the base type for trivial assignments, and hence it
5966 compute_record_mode (CLASSTYPE_AS_BASE (t));
5968 virtuals = modify_all_vtables (t, nreverse (virtuals));
5970 /* If necessary, create the primary vtable for this class. */
5971 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5973 /* We must enter these virtuals into the table. */
5974 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5975 build_primary_vtable (NULL_TREE, t);
5976 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5977 /* Here we know enough to change the type of our virtual
5978 function table, but we will wait until later this function. */
5979 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5982 if (TYPE_CONTAINS_VPTR_P (t))
5987 if (BINFO_VTABLE (TYPE_BINFO (t)))
5988 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5989 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5990 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5992 /* Add entries for virtual functions introduced by this class. */
5993 BINFO_VIRTUALS (TYPE_BINFO (t))
5994 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5996 /* Set DECL_VINDEX for all functions declared in this class. */
5997 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5999 fn = TREE_CHAIN (fn),
6000 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
6001 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
6003 tree fndecl = BV_FN (fn);
6005 if (DECL_THUNK_P (fndecl))
6006 /* A thunk. We should never be calling this entry directly
6007 from this vtable -- we'd use the entry for the non
6008 thunk base function. */
6009 DECL_VINDEX (fndecl) = NULL_TREE;
6010 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
6011 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
6015 finish_struct_bits (t);
6016 set_method_tm_attributes (t);
6018 /* Complete the rtl for any static member objects of the type we're
6020 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
6021 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
6022 && TREE_TYPE (x) != error_mark_node
6023 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
6024 DECL_MODE (x) = TYPE_MODE (t);
6026 /* Done with FIELDS...now decide whether to sort these for
6027 faster lookups later.
6029 We use a small number because most searches fail (succeeding
6030 ultimately as the search bores through the inheritance
6031 hierarchy), and we want this failure to occur quickly. */
6033 n_fields = count_fields (TYPE_FIELDS (t));
6036 struct sorted_fields_type *field_vec = sorted_fields_type_new (n_fields);
6037 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
6038 qsort (field_vec->elts, n_fields, sizeof (tree),
6040 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
6043 /* Complain if one of the field types requires lower visibility. */
6044 constrain_class_visibility (t);
6046 /* Make the rtl for any new vtables we have created, and unmark
6047 the base types we marked. */
6050 /* Build the VTT for T. */
6053 /* This warning does not make sense for Java classes, since they
6054 cannot have destructors. */
6055 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
6059 dtor = CLASSTYPE_DESTRUCTORS (t);
6060 if (/* An implicitly declared destructor is always public. And,
6061 if it were virtual, we would have created it by now. */
6063 || (!DECL_VINDEX (dtor)
6064 && (/* public non-virtual */
6065 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
6066 || (/* non-public non-virtual with friends */
6067 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
6068 && (CLASSTYPE_FRIEND_CLASSES (t)
6069 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
6070 warning (OPT_Wnon_virtual_dtor,
6071 "%q#T has virtual functions and accessible"
6072 " non-virtual destructor", t);
6077 if (warn_overloaded_virtual)
6080 /* Class layout, assignment of virtual table slots, etc., is now
6081 complete. Give the back end a chance to tweak the visibility of
6082 the class or perform any other required target modifications. */
6083 targetm.cxx.adjust_class_at_definition (t);
6085 maybe_suppress_debug_info (t);
6087 dump_class_hierarchy (t);
6089 /* Finish debugging output for this type. */
6090 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
6092 if (TYPE_TRANSPARENT_AGGR (t))
6094 tree field = first_field (t);
6095 if (field == NULL_TREE || error_operand_p (field))
6097 error ("type transparent class %qT does not have any fields", t);
6098 TYPE_TRANSPARENT_AGGR (t) = 0;
6100 else if (DECL_ARTIFICIAL (field))
6102 if (DECL_FIELD_IS_BASE (field))
6103 error ("type transparent class %qT has base classes", t);
6106 gcc_checking_assert (DECL_VIRTUAL_P (field));
6107 error ("type transparent class %qT has virtual functions", t);
6109 TYPE_TRANSPARENT_AGGR (t) = 0;
6114 /* When T was built up, the member declarations were added in reverse
6115 order. Rearrange them to declaration order. */
6118 unreverse_member_declarations (tree t)
6124 /* The following lists are all in reverse order. Put them in
6125 declaration order now. */
6126 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
6127 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
6129 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
6130 reverse order, so we can't just use nreverse. */
6132 for (x = TYPE_FIELDS (t);
6133 x && TREE_CODE (x) != TYPE_DECL;
6136 next = DECL_CHAIN (x);
6137 DECL_CHAIN (x) = prev;
6142 DECL_CHAIN (TYPE_FIELDS (t)) = x;
6144 TYPE_FIELDS (t) = prev;
6149 finish_struct (tree t, tree attributes)
6151 location_t saved_loc = input_location;
6153 /* Now that we've got all the field declarations, reverse everything
6155 unreverse_member_declarations (t);
6157 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
6159 /* Nadger the current location so that diagnostics point to the start of
6160 the struct, not the end. */
6161 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
6163 if (processing_template_decl)
6167 finish_struct_methods (t);
6168 TYPE_SIZE (t) = bitsize_zero_node;
6169 TYPE_SIZE_UNIT (t) = size_zero_node;
6171 /* We need to emit an error message if this type was used as a parameter
6172 and it is an abstract type, even if it is a template. We construct
6173 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
6174 account and we call complete_vars with this type, which will check
6175 the PARM_DECLS. Note that while the type is being defined,
6176 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
6177 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
6178 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
6179 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
6180 if (DECL_PURE_VIRTUAL_P (x))
6181 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
6184 /* Remember current #pragma pack value. */
6185 TYPE_PRECISION (t) = maximum_field_alignment;
6188 finish_struct_1 (t);
6190 input_location = saved_loc;
6192 TYPE_BEING_DEFINED (t) = 0;
6194 if (current_class_type)
6197 error ("trying to finish struct, but kicked out due to previous parse errors");
6199 if (processing_template_decl && at_function_scope_p ())
6200 add_stmt (build_min (TAG_DEFN, t));
6205 /* Return the dynamic type of INSTANCE, if known.
6206 Used to determine whether the virtual function table is needed
6209 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6210 of our knowledge of its type. *NONNULL should be initialized
6211 before this function is called. */
6214 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
6216 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
6218 switch (TREE_CODE (instance))
6221 if (POINTER_TYPE_P (TREE_TYPE (instance)))
6224 return RECUR (TREE_OPERAND (instance, 0));
6227 /* This is a call to a constructor, hence it's never zero. */
6228 if (TREE_HAS_CONSTRUCTOR (instance))
6232 return TREE_TYPE (instance);
6237 /* This is a call to a constructor, hence it's never zero. */
6238 if (TREE_HAS_CONSTRUCTOR (instance))
6242 return TREE_TYPE (instance);
6244 return RECUR (TREE_OPERAND (instance, 0));
6246 case POINTER_PLUS_EXPR:
6249 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
6250 return RECUR (TREE_OPERAND (instance, 0));
6251 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
6252 /* Propagate nonnull. */
6253 return RECUR (TREE_OPERAND (instance, 0));
6258 return RECUR (TREE_OPERAND (instance, 0));
6261 instance = TREE_OPERAND (instance, 0);
6264 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
6265 with a real object -- given &p->f, p can still be null. */
6266 tree t = get_base_address (instance);
6267 /* ??? Probably should check DECL_WEAK here. */
6268 if (t && DECL_P (t))
6271 return RECUR (instance);
6274 /* If this component is really a base class reference, then the field
6275 itself isn't definitive. */
6276 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
6277 return RECUR (TREE_OPERAND (instance, 0));
6278 return RECUR (TREE_OPERAND (instance, 1));
6282 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
6283 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
6287 return TREE_TYPE (TREE_TYPE (instance));
6289 /* fall through... */
6293 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
6297 return TREE_TYPE (instance);
6299 else if (instance == current_class_ptr)
6304 /* if we're in a ctor or dtor, we know our type. If
6305 current_class_ptr is set but we aren't in a function, we're in
6306 an NSDMI (and therefore a constructor). */
6307 if (current_scope () != current_function_decl
6308 || (DECL_LANG_SPECIFIC (current_function_decl)
6309 && (DECL_CONSTRUCTOR_P (current_function_decl)
6310 || DECL_DESTRUCTOR_P (current_function_decl))))
6314 return TREE_TYPE (TREE_TYPE (instance));
6317 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
6319 /* We only need one hash table because it is always left empty. */
6322 ht = htab_create (37,
6327 /* Reference variables should be references to objects. */
6331 /* Enter the INSTANCE in a table to prevent recursion; a
6332 variable's initializer may refer to the variable
6334 if (TREE_CODE (instance) == VAR_DECL
6335 && DECL_INITIAL (instance)
6336 && !type_dependent_expression_p_push (DECL_INITIAL (instance))
6337 && !htab_find (ht, instance))
6342 slot = htab_find_slot (ht, instance, INSERT);
6344 type = RECUR (DECL_INITIAL (instance));
6345 htab_remove_elt (ht, instance);
6358 /* Return nonzero if the dynamic type of INSTANCE is known, and
6359 equivalent to the static type. We also handle the case where
6360 INSTANCE is really a pointer. Return negative if this is a
6361 ctor/dtor. There the dynamic type is known, but this might not be
6362 the most derived base of the original object, and hence virtual
6363 bases may not be layed out according to this type.
6365 Used to determine whether the virtual function table is needed
6368 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6369 of our knowledge of its type. *NONNULL should be initialized
6370 before this function is called. */
6373 resolves_to_fixed_type_p (tree instance, int* nonnull)
6375 tree t = TREE_TYPE (instance);
6379 if (processing_template_decl)
6381 /* In a template we only care about the type of the result. */
6387 fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
6388 if (fixed == NULL_TREE)
6390 if (POINTER_TYPE_P (t))
6392 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
6394 return cdtorp ? -1 : 1;
6399 init_class_processing (void)
6401 current_class_depth = 0;
6402 current_class_stack_size = 10;
6404 = XNEWVEC (struct class_stack_node, current_class_stack_size);
6405 local_classes = VEC_alloc (tree, gc, 8);
6406 sizeof_biggest_empty_class = size_zero_node;
6408 ridpointers[(int) RID_PUBLIC] = access_public_node;
6409 ridpointers[(int) RID_PRIVATE] = access_private_node;
6410 ridpointers[(int) RID_PROTECTED] = access_protected_node;
6413 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
6416 restore_class_cache (void)
6420 /* We are re-entering the same class we just left, so we don't
6421 have to search the whole inheritance matrix to find all the
6422 decls to bind again. Instead, we install the cached
6423 class_shadowed list and walk through it binding names. */
6424 push_binding_level (previous_class_level);
6425 class_binding_level = previous_class_level;
6426 /* Restore IDENTIFIER_TYPE_VALUE. */
6427 for (type = class_binding_level->type_shadowed;
6429 type = TREE_CHAIN (type))
6430 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
6433 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
6434 appropriate for TYPE.
6436 So that we may avoid calls to lookup_name, we cache the _TYPE
6437 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
6439 For multiple inheritance, we perform a two-pass depth-first search
6440 of the type lattice. */
6443 pushclass (tree type)
6445 class_stack_node_t csn;
6447 type = TYPE_MAIN_VARIANT (type);
6449 /* Make sure there is enough room for the new entry on the stack. */
6450 if (current_class_depth + 1 >= current_class_stack_size)
6452 current_class_stack_size *= 2;
6454 = XRESIZEVEC (struct class_stack_node, current_class_stack,
6455 current_class_stack_size);
6458 /* Insert a new entry on the class stack. */
6459 csn = current_class_stack + current_class_depth;
6460 csn->name = current_class_name;
6461 csn->type = current_class_type;
6462 csn->access = current_access_specifier;
6463 csn->names_used = 0;
6465 current_class_depth++;
6467 /* Now set up the new type. */
6468 current_class_name = TYPE_NAME (type);
6469 if (TREE_CODE (current_class_name) == TYPE_DECL)
6470 current_class_name = DECL_NAME (current_class_name);
6471 current_class_type = type;
6473 /* By default, things in classes are private, while things in
6474 structures or unions are public. */
6475 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
6476 ? access_private_node
6477 : access_public_node);
6479 if (previous_class_level
6480 && type != previous_class_level->this_entity
6481 && current_class_depth == 1)
6483 /* Forcibly remove any old class remnants. */
6484 invalidate_class_lookup_cache ();
6487 if (!previous_class_level
6488 || type != previous_class_level->this_entity
6489 || current_class_depth > 1)
6492 restore_class_cache ();
6495 /* When we exit a toplevel class scope, we save its binding level so
6496 that we can restore it quickly. Here, we've entered some other
6497 class, so we must invalidate our cache. */
6500 invalidate_class_lookup_cache (void)
6502 previous_class_level = NULL;
6505 /* Get out of the current class scope. If we were in a class scope
6506 previously, that is the one popped to. */
6513 current_class_depth--;
6514 current_class_name = current_class_stack[current_class_depth].name;
6515 current_class_type = current_class_stack[current_class_depth].type;
6516 current_access_specifier = current_class_stack[current_class_depth].access;
6517 if (current_class_stack[current_class_depth].names_used)
6518 splay_tree_delete (current_class_stack[current_class_depth].names_used);
6521 /* Mark the top of the class stack as hidden. */
6524 push_class_stack (void)
6526 if (current_class_depth)
6527 ++current_class_stack[current_class_depth - 1].hidden;
6530 /* Mark the top of the class stack as un-hidden. */
6533 pop_class_stack (void)
6535 if (current_class_depth)
6536 --current_class_stack[current_class_depth - 1].hidden;
6539 /* Returns 1 if the class type currently being defined is either T or
6540 a nested type of T. */
6543 currently_open_class (tree t)
6547 if (!CLASS_TYPE_P (t))
6550 t = TYPE_MAIN_VARIANT (t);
6552 /* We start looking from 1 because entry 0 is from global scope,
6554 for (i = current_class_depth; i > 0; --i)
6557 if (i == current_class_depth)
6558 c = current_class_type;
6561 if (current_class_stack[i].hidden)
6563 c = current_class_stack[i].type;
6567 if (same_type_p (c, t))
6573 /* If either current_class_type or one of its enclosing classes are derived
6574 from T, return the appropriate type. Used to determine how we found
6575 something via unqualified lookup. */
6578 currently_open_derived_class (tree t)
6582 /* The bases of a dependent type are unknown. */
6583 if (dependent_type_p (t))
6586 if (!current_class_type)
6589 if (DERIVED_FROM_P (t, current_class_type))
6590 return current_class_type;
6592 for (i = current_class_depth - 1; i > 0; --i)
6594 if (current_class_stack[i].hidden)
6596 if (DERIVED_FROM_P (t, current_class_stack[i].type))
6597 return current_class_stack[i].type;
6603 /* Returns the innermost class type which is not a lambda closure type. */
6606 current_nonlambda_class_type (void)
6610 /* We start looking from 1 because entry 0 is from global scope,
6612 for (i = current_class_depth; i > 0; --i)
6615 if (i == current_class_depth)
6616 c = current_class_type;
6619 if (current_class_stack[i].hidden)
6621 c = current_class_stack[i].type;
6625 if (!LAMBDA_TYPE_P (c))
6631 /* When entering a class scope, all enclosing class scopes' names with
6632 static meaning (static variables, static functions, types and
6633 enumerators) have to be visible. This recursive function calls
6634 pushclass for all enclosing class contexts until global or a local
6635 scope is reached. TYPE is the enclosed class. */
6638 push_nested_class (tree type)
6640 /* A namespace might be passed in error cases, like A::B:C. */
6641 if (type == NULL_TREE
6642 || !CLASS_TYPE_P (type))
6645 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
6650 /* Undoes a push_nested_class call. */
6653 pop_nested_class (void)
6655 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
6658 if (context && CLASS_TYPE_P (context))
6659 pop_nested_class ();
6662 /* Returns the number of extern "LANG" blocks we are nested within. */
6665 current_lang_depth (void)
6667 return VEC_length (tree, current_lang_base);
6670 /* Set global variables CURRENT_LANG_NAME to appropriate value
6671 so that behavior of name-mangling machinery is correct. */
6674 push_lang_context (tree name)
6676 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
6678 if (name == lang_name_cplusplus)
6680 current_lang_name = name;
6682 else if (name == lang_name_java)
6684 current_lang_name = name;
6685 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6686 (See record_builtin_java_type in decl.c.) However, that causes
6687 incorrect debug entries if these types are actually used.
6688 So we re-enable debug output after extern "Java". */
6689 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
6690 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
6691 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
6692 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
6693 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
6694 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
6695 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
6696 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
6698 else if (name == lang_name_c)
6700 current_lang_name = name;
6703 error ("language string %<\"%E\"%> not recognized", name);
6706 /* Get out of the current language scope. */
6709 pop_lang_context (void)
6711 current_lang_name = VEC_pop (tree, current_lang_base);
6714 /* Type instantiation routines. */
6716 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6717 matches the TARGET_TYPE. If there is no satisfactory match, return
6718 error_mark_node, and issue an error & warning messages under
6719 control of FLAGS. Permit pointers to member function if FLAGS
6720 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6721 a template-id, and EXPLICIT_TARGS are the explicitly provided
6724 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6725 is the base path used to reference those member functions. If
6726 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6727 resolved to a member function, access checks will be performed and
6728 errors issued if appropriate. */
6731 resolve_address_of_overloaded_function (tree target_type,
6733 tsubst_flags_t flags,
6735 tree explicit_targs,
6738 /* Here's what the standard says:
6742 If the name is a function template, template argument deduction
6743 is done, and if the argument deduction succeeds, the deduced
6744 arguments are used to generate a single template function, which
6745 is added to the set of overloaded functions considered.
6747 Non-member functions and static member functions match targets of
6748 type "pointer-to-function" or "reference-to-function." Nonstatic
6749 member functions match targets of type "pointer-to-member
6750 function;" the function type of the pointer to member is used to
6751 select the member function from the set of overloaded member
6752 functions. If a nonstatic member function is selected, the
6753 reference to the overloaded function name is required to have the
6754 form of a pointer to member as described in 5.3.1.
6756 If more than one function is selected, any template functions in
6757 the set are eliminated if the set also contains a non-template
6758 function, and any given template function is eliminated if the
6759 set contains a second template function that is more specialized
6760 than the first according to the partial ordering rules 14.5.5.2.
6761 After such eliminations, if any, there shall remain exactly one
6762 selected function. */
6765 /* We store the matches in a TREE_LIST rooted here. The functions
6766 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6767 interoperability with most_specialized_instantiation. */
6768 tree matches = NULL_TREE;
6770 tree target_fn_type;
6772 /* By the time we get here, we should be seeing only real
6773 pointer-to-member types, not the internal POINTER_TYPE to
6774 METHOD_TYPE representation. */
6775 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6776 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6778 gcc_assert (is_overloaded_fn (overload));
6780 /* Check that the TARGET_TYPE is reasonable. */
6781 if (TYPE_PTRFN_P (target_type))
6783 else if (TYPE_PTRMEMFUNC_P (target_type))
6784 /* This is OK, too. */
6786 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6787 /* This is OK, too. This comes from a conversion to reference
6789 target_type = build_reference_type (target_type);
6792 if (flags & tf_error)
6793 error ("cannot resolve overloaded function %qD based on"
6794 " conversion to type %qT",
6795 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6796 return error_mark_node;
6799 /* Non-member functions and static member functions match targets of type
6800 "pointer-to-function" or "reference-to-function." Nonstatic member
6801 functions match targets of type "pointer-to-member-function;" the
6802 function type of the pointer to member is used to select the member
6803 function from the set of overloaded member functions.
6805 So figure out the FUNCTION_TYPE that we want to match against. */
6806 target_fn_type = static_fn_type (target_type);
6808 /* If we can find a non-template function that matches, we can just
6809 use it. There's no point in generating template instantiations
6810 if we're just going to throw them out anyhow. But, of course, we
6811 can only do this when we don't *need* a template function. */
6816 for (fns = overload; fns; fns = OVL_NEXT (fns))
6818 tree fn = OVL_CURRENT (fns);
6820 if (TREE_CODE (fn) == TEMPLATE_DECL)
6821 /* We're not looking for templates just yet. */
6824 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6826 /* We're looking for a non-static member, and this isn't
6827 one, or vice versa. */
6830 /* Ignore functions which haven't been explicitly
6832 if (DECL_ANTICIPATED (fn))
6835 /* See if there's a match. */
6836 if (same_type_p (target_fn_type, static_fn_type (fn)))
6837 matches = tree_cons (fn, NULL_TREE, matches);
6841 /* Now, if we've already got a match (or matches), there's no need
6842 to proceed to the template functions. But, if we don't have a
6843 match we need to look at them, too. */
6846 tree target_arg_types;
6847 tree target_ret_type;
6850 unsigned int nargs, ia;
6853 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6854 target_ret_type = TREE_TYPE (target_fn_type);
6856 nargs = list_length (target_arg_types);
6857 args = XALLOCAVEC (tree, nargs);
6858 for (arg = target_arg_types, ia = 0;
6859 arg != NULL_TREE && arg != void_list_node;
6860 arg = TREE_CHAIN (arg), ++ia)
6861 args[ia] = TREE_VALUE (arg);
6864 for (fns = overload; fns; fns = OVL_NEXT (fns))
6866 tree fn = OVL_CURRENT (fns);
6870 if (TREE_CODE (fn) != TEMPLATE_DECL)
6871 /* We're only looking for templates. */
6874 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6876 /* We're not looking for a non-static member, and this is
6877 one, or vice versa. */
6880 /* Try to do argument deduction. */
6881 targs = make_tree_vec (DECL_NTPARMS (fn));
6882 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6883 target_ret_type, DEDUCE_EXACT,
6884 LOOKUP_NORMAL, false))
6885 /* Argument deduction failed. */
6888 /* Instantiate the template. */
6889 instantiation = instantiate_template (fn, targs, flags);
6890 if (instantiation == error_mark_node)
6891 /* Instantiation failed. */
6894 /* See if there's a match. */
6895 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
6896 matches = tree_cons (instantiation, fn, matches);
6899 /* Now, remove all but the most specialized of the matches. */
6902 tree match = most_specialized_instantiation (matches);
6904 if (match != error_mark_node)
6905 matches = tree_cons (TREE_PURPOSE (match),
6911 /* Now we should have exactly one function in MATCHES. */
6912 if (matches == NULL_TREE)
6914 /* There were *no* matches. */
6915 if (flags & tf_error)
6917 error ("no matches converting function %qD to type %q#T",
6918 DECL_NAME (OVL_CURRENT (overload)),
6921 print_candidates (overload);
6923 return error_mark_node;
6925 else if (TREE_CHAIN (matches))
6927 /* There were too many matches. First check if they're all
6928 the same function. */
6931 fn = TREE_PURPOSE (matches);
6932 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6933 if (!decls_match (fn, TREE_PURPOSE (match)))
6938 if (flags & tf_error)
6940 error ("converting overloaded function %qD to type %q#T is ambiguous",
6941 DECL_NAME (OVL_FUNCTION (overload)),
6944 /* Since print_candidates expects the functions in the
6945 TREE_VALUE slot, we flip them here. */
6946 for (match = matches; match; match = TREE_CHAIN (match))
6947 TREE_VALUE (match) = TREE_PURPOSE (match);
6949 print_candidates (matches);
6952 return error_mark_node;
6956 /* Good, exactly one match. Now, convert it to the correct type. */
6957 fn = TREE_PURPOSE (matches);
6959 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6960 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6962 static int explained;
6964 if (!(flags & tf_error))
6965 return error_mark_node;
6967 permerror (input_location, "assuming pointer to member %qD", fn);
6970 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6975 /* If we're doing overload resolution purely for the purpose of
6976 determining conversion sequences, we should not consider the
6977 function used. If this conversion sequence is selected, the
6978 function will be marked as used at this point. */
6979 if (!(flags & tf_conv))
6981 /* Make =delete work with SFINAE. */
6982 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6983 return error_mark_node;
6988 /* We could not check access to member functions when this
6989 expression was originally created since we did not know at that
6990 time to which function the expression referred. */
6991 if (!(flags & tf_no_access_control)
6992 && DECL_FUNCTION_MEMBER_P (fn))
6994 gcc_assert (access_path);
6995 perform_or_defer_access_check (access_path, fn, fn);
6998 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6999 return cp_build_addr_expr (fn, flags);
7002 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
7003 will mark the function as addressed, but here we must do it
7005 cxx_mark_addressable (fn);
7011 /* This function will instantiate the type of the expression given in
7012 RHS to match the type of LHSTYPE. If errors exist, then return
7013 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
7014 we complain on errors. If we are not complaining, never modify rhs,
7015 as overload resolution wants to try many possible instantiations, in
7016 the hope that at least one will work.
7018 For non-recursive calls, LHSTYPE should be a function, pointer to
7019 function, or a pointer to member function. */
7022 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
7024 tsubst_flags_t flags_in = flags;
7025 tree access_path = NULL_TREE;
7027 flags &= ~tf_ptrmem_ok;
7029 if (lhstype == unknown_type_node)
7031 if (flags & tf_error)
7032 error ("not enough type information");
7033 return error_mark_node;
7036 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
7038 if (same_type_p (lhstype, TREE_TYPE (rhs)))
7040 if (flag_ms_extensions
7041 && TYPE_PTRMEMFUNC_P (lhstype)
7042 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
7043 /* Microsoft allows `A::f' to be resolved to a
7044 pointer-to-member. */
7048 if (flags & tf_error)
7049 error ("cannot convert %qE from type %qT to type %qT",
7050 rhs, TREE_TYPE (rhs), lhstype);
7051 return error_mark_node;
7055 if (BASELINK_P (rhs))
7057 access_path = BASELINK_ACCESS_BINFO (rhs);
7058 rhs = BASELINK_FUNCTIONS (rhs);
7061 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
7062 deduce any type information. */
7063 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
7065 if (flags & tf_error)
7066 error ("not enough type information");
7067 return error_mark_node;
7070 /* There only a few kinds of expressions that may have a type
7071 dependent on overload resolution. */
7072 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
7073 || TREE_CODE (rhs) == COMPONENT_REF
7074 || really_overloaded_fn (rhs)
7075 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
7077 /* This should really only be used when attempting to distinguish
7078 what sort of a pointer to function we have. For now, any
7079 arithmetic operation which is not supported on pointers
7080 is rejected as an error. */
7082 switch (TREE_CODE (rhs))
7086 tree member = TREE_OPERAND (rhs, 1);
7088 member = instantiate_type (lhstype, member, flags);
7089 if (member != error_mark_node
7090 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
7091 /* Do not lose object's side effects. */
7092 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
7093 TREE_OPERAND (rhs, 0), member);
7098 rhs = TREE_OPERAND (rhs, 1);
7099 if (BASELINK_P (rhs))
7100 return instantiate_type (lhstype, rhs, flags_in);
7102 /* This can happen if we are forming a pointer-to-member for a
7104 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
7108 case TEMPLATE_ID_EXPR:
7110 tree fns = TREE_OPERAND (rhs, 0);
7111 tree args = TREE_OPERAND (rhs, 1);
7114 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
7115 /*template_only=*/true,
7122 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
7123 /*template_only=*/false,
7124 /*explicit_targs=*/NULL_TREE,
7129 if (PTRMEM_OK_P (rhs))
7130 flags |= tf_ptrmem_ok;
7132 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
7136 return error_mark_node;
7141 return error_mark_node;
7144 /* Return the name of the virtual function pointer field
7145 (as an IDENTIFIER_NODE) for the given TYPE. Note that
7146 this may have to look back through base types to find the
7147 ultimate field name. (For single inheritance, these could
7148 all be the same name. Who knows for multiple inheritance). */
7151 get_vfield_name (tree type)
7153 tree binfo, base_binfo;
7156 for (binfo = TYPE_BINFO (type);
7157 BINFO_N_BASE_BINFOS (binfo);
7160 base_binfo = BINFO_BASE_BINFO (binfo, 0);
7162 if (BINFO_VIRTUAL_P (base_binfo)
7163 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
7167 type = BINFO_TYPE (binfo);
7168 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
7169 + TYPE_NAME_LENGTH (type) + 2);
7170 sprintf (buf, VFIELD_NAME_FORMAT,
7171 IDENTIFIER_POINTER (constructor_name (type)));
7172 return get_identifier (buf);
7176 print_class_statistics (void)
7178 #ifdef GATHER_STATISTICS
7179 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
7180 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
7183 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
7184 n_vtables, n_vtable_searches);
7185 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
7186 n_vtable_entries, n_vtable_elems);
7191 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
7192 according to [class]:
7193 The class-name is also inserted
7194 into the scope of the class itself. For purposes of access checking,
7195 the inserted class name is treated as if it were a public member name. */
7198 build_self_reference (void)
7200 tree name = constructor_name (current_class_type);
7201 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
7204 DECL_NONLOCAL (value) = 1;
7205 DECL_CONTEXT (value) = current_class_type;
7206 DECL_ARTIFICIAL (value) = 1;
7207 SET_DECL_SELF_REFERENCE_P (value);
7208 set_underlying_type (value);
7210 if (processing_template_decl)
7211 value = push_template_decl (value);
7213 saved_cas = current_access_specifier;
7214 current_access_specifier = access_public_node;
7215 finish_member_declaration (value);
7216 current_access_specifier = saved_cas;
7219 /* Returns 1 if TYPE contains only padding bytes. */
7222 is_empty_class (tree type)
7224 if (type == error_mark_node)
7227 if (! CLASS_TYPE_P (type))
7230 /* In G++ 3.2, whether or not a class was empty was determined by
7231 looking at its size. */
7232 if (abi_version_at_least (2))
7233 return CLASSTYPE_EMPTY_P (type);
7235 return integer_zerop (CLASSTYPE_SIZE (type));
7238 /* Returns true if TYPE contains an empty class. */
7241 contains_empty_class_p (tree type)
7243 if (is_empty_class (type))
7245 if (CLASS_TYPE_P (type))
7252 for (binfo = TYPE_BINFO (type), i = 0;
7253 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7254 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
7256 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
7257 if (TREE_CODE (field) == FIELD_DECL
7258 && !DECL_ARTIFICIAL (field)
7259 && is_empty_class (TREE_TYPE (field)))
7262 else if (TREE_CODE (type) == ARRAY_TYPE)
7263 return contains_empty_class_p (TREE_TYPE (type));
7267 /* Returns true if TYPE contains no actual data, just various
7268 possible combinations of empty classes and possibly a vptr. */
7271 is_really_empty_class (tree type)
7273 if (CLASS_TYPE_P (type))
7280 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
7281 out, but we'd like to be able to check this before then. */
7282 if (COMPLETE_TYPE_P (type) && is_empty_class (type))
7285 for (binfo = TYPE_BINFO (type), i = 0;
7286 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7287 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
7289 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
7290 if (TREE_CODE (field) == FIELD_DECL
7291 && !DECL_ARTIFICIAL (field)
7292 && !is_really_empty_class (TREE_TYPE (field)))
7296 else if (TREE_CODE (type) == ARRAY_TYPE)
7297 return is_really_empty_class (TREE_TYPE (type));
7301 /* Note that NAME was looked up while the current class was being
7302 defined and that the result of that lookup was DECL. */
7305 maybe_note_name_used_in_class (tree name, tree decl)
7307 splay_tree names_used;
7309 /* If we're not defining a class, there's nothing to do. */
7310 if (!(innermost_scope_kind() == sk_class
7311 && TYPE_BEING_DEFINED (current_class_type)
7312 && !LAMBDA_TYPE_P (current_class_type)))
7315 /* If there's already a binding for this NAME, then we don't have
7316 anything to worry about. */
7317 if (lookup_member (current_class_type, name,
7318 /*protect=*/0, /*want_type=*/false, tf_warning_or_error))
7321 if (!current_class_stack[current_class_depth - 1].names_used)
7322 current_class_stack[current_class_depth - 1].names_used
7323 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
7324 names_used = current_class_stack[current_class_depth - 1].names_used;
7326 splay_tree_insert (names_used,
7327 (splay_tree_key) name,
7328 (splay_tree_value) decl);
7331 /* Note that NAME was declared (as DECL) in the current class. Check
7332 to see that the declaration is valid. */
7335 note_name_declared_in_class (tree name, tree decl)
7337 splay_tree names_used;
7340 /* Look to see if we ever used this name. */
7342 = current_class_stack[current_class_depth - 1].names_used;
7345 /* The C language allows members to be declared with a type of the same
7346 name, and the C++ standard says this diagnostic is not required. So
7347 allow it in extern "C" blocks unless predantic is specified.
7348 Allow it in all cases if -ms-extensions is specified. */
7349 if ((!pedantic && current_lang_name == lang_name_c)
7350 || flag_ms_extensions)
7352 n = splay_tree_lookup (names_used, (splay_tree_key) name);
7355 /* [basic.scope.class]
7357 A name N used in a class S shall refer to the same declaration
7358 in its context and when re-evaluated in the completed scope of
7360 permerror (input_location, "declaration of %q#D", decl);
7361 permerror (input_location, "changes meaning of %qD from %q+#D",
7362 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
7366 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
7367 Secondary vtables are merged with primary vtables; this function
7368 will return the VAR_DECL for the primary vtable. */
7371 get_vtbl_decl_for_binfo (tree binfo)
7375 decl = BINFO_VTABLE (binfo);
7376 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
7378 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
7379 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
7382 gcc_assert (TREE_CODE (decl) == VAR_DECL);
7387 /* Returns the binfo for the primary base of BINFO. If the resulting
7388 BINFO is a virtual base, and it is inherited elsewhere in the
7389 hierarchy, then the returned binfo might not be the primary base of
7390 BINFO in the complete object. Check BINFO_PRIMARY_P or
7391 BINFO_LOST_PRIMARY_P to be sure. */
7394 get_primary_binfo (tree binfo)
7398 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
7402 return copied_binfo (primary_base, binfo);
7405 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
7408 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
7411 fprintf (stream, "%*s", indent, "");
7415 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
7416 INDENT should be zero when called from the top level; it is
7417 incremented recursively. IGO indicates the next expected BINFO in
7418 inheritance graph ordering. */
7421 dump_class_hierarchy_r (FILE *stream,
7431 indented = maybe_indent_hierarchy (stream, indent, 0);
7432 fprintf (stream, "%s (0x%lx) ",
7433 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
7434 (unsigned long) binfo);
7437 fprintf (stream, "alternative-path\n");
7440 igo = TREE_CHAIN (binfo);
7442 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
7443 tree_low_cst (BINFO_OFFSET (binfo), 0));
7444 if (is_empty_class (BINFO_TYPE (binfo)))
7445 fprintf (stream, " empty");
7446 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
7447 fprintf (stream, " nearly-empty");
7448 if (BINFO_VIRTUAL_P (binfo))
7449 fprintf (stream, " virtual");
7450 fprintf (stream, "\n");
7453 if (BINFO_PRIMARY_P (binfo))
7455 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7456 fprintf (stream, " primary-for %s (0x%lx)",
7457 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
7458 TFF_PLAIN_IDENTIFIER),
7459 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
7461 if (BINFO_LOST_PRIMARY_P (binfo))
7463 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7464 fprintf (stream, " lost-primary");
7467 fprintf (stream, "\n");
7469 if (!(flags & TDF_SLIM))
7473 if (BINFO_SUBVTT_INDEX (binfo))
7475 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7476 fprintf (stream, " subvttidx=%s",
7477 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
7478 TFF_PLAIN_IDENTIFIER));
7480 if (BINFO_VPTR_INDEX (binfo))
7482 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7483 fprintf (stream, " vptridx=%s",
7484 expr_as_string (BINFO_VPTR_INDEX (binfo),
7485 TFF_PLAIN_IDENTIFIER));
7487 if (BINFO_VPTR_FIELD (binfo))
7489 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7490 fprintf (stream, " vbaseoffset=%s",
7491 expr_as_string (BINFO_VPTR_FIELD (binfo),
7492 TFF_PLAIN_IDENTIFIER));
7494 if (BINFO_VTABLE (binfo))
7496 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7497 fprintf (stream, " vptr=%s",
7498 expr_as_string (BINFO_VTABLE (binfo),
7499 TFF_PLAIN_IDENTIFIER));
7503 fprintf (stream, "\n");
7506 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
7507 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
7512 /* Dump the BINFO hierarchy for T. */
7515 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
7517 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7518 fprintf (stream, " size=%lu align=%lu\n",
7519 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
7520 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
7521 fprintf (stream, " base size=%lu base align=%lu\n",
7522 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
7524 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
7526 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
7527 fprintf (stream, "\n");
7530 /* Debug interface to hierarchy dumping. */
7533 debug_class (tree t)
7535 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
7539 dump_class_hierarchy (tree t)
7542 FILE *stream = dump_begin (TDI_class, &flags);
7546 dump_class_hierarchy_1 (stream, flags, t);
7547 dump_end (TDI_class, stream);
7552 dump_array (FILE * stream, tree decl)
7555 unsigned HOST_WIDE_INT ix;
7557 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
7559 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
7561 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
7562 fprintf (stream, " %s entries",
7563 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
7564 TFF_PLAIN_IDENTIFIER));
7565 fprintf (stream, "\n");
7567 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
7569 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
7570 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
7574 dump_vtable (tree t, tree binfo, tree vtable)
7577 FILE *stream = dump_begin (TDI_class, &flags);
7582 if (!(flags & TDF_SLIM))
7584 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
7586 fprintf (stream, "%s for %s",
7587 ctor_vtbl_p ? "Construction vtable" : "Vtable",
7588 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
7591 if (!BINFO_VIRTUAL_P (binfo))
7592 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
7593 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7595 fprintf (stream, "\n");
7596 dump_array (stream, vtable);
7597 fprintf (stream, "\n");
7600 dump_end (TDI_class, stream);
7604 dump_vtt (tree t, tree vtt)
7607 FILE *stream = dump_begin (TDI_class, &flags);
7612 if (!(flags & TDF_SLIM))
7614 fprintf (stream, "VTT for %s\n",
7615 type_as_string (t, TFF_PLAIN_IDENTIFIER));
7616 dump_array (stream, vtt);
7617 fprintf (stream, "\n");
7620 dump_end (TDI_class, stream);
7623 /* Dump a function or thunk and its thunkees. */
7626 dump_thunk (FILE *stream, int indent, tree thunk)
7628 static const char spaces[] = " ";
7629 tree name = DECL_NAME (thunk);
7632 fprintf (stream, "%.*s%p %s %s", indent, spaces,
7634 !DECL_THUNK_P (thunk) ? "function"
7635 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
7636 name ? IDENTIFIER_POINTER (name) : "<unset>");
7637 if (DECL_THUNK_P (thunk))
7639 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
7640 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
7642 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
7643 if (!virtual_adjust)
7645 else if (DECL_THIS_THUNK_P (thunk))
7646 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
7647 tree_low_cst (virtual_adjust, 0));
7649 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
7650 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
7651 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
7652 if (THUNK_ALIAS (thunk))
7653 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
7655 fprintf (stream, "\n");
7656 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
7657 dump_thunk (stream, indent + 2, thunks);
7660 /* Dump the thunks for FN. */
7663 debug_thunks (tree fn)
7665 dump_thunk (stderr, 0, fn);
7668 /* Virtual function table initialization. */
7670 /* Create all the necessary vtables for T and its base classes. */
7673 finish_vtbls (tree t)
7676 VEC(constructor_elt,gc) *v = NULL;
7677 tree vtable = BINFO_VTABLE (TYPE_BINFO (t));
7679 /* We lay out the primary and secondary vtables in one contiguous
7680 vtable. The primary vtable is first, followed by the non-virtual
7681 secondary vtables in inheritance graph order. */
7682 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t),
7685 /* Then come the virtual bases, also in inheritance graph order. */
7686 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
7688 if (!BINFO_VIRTUAL_P (vbase))
7690 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), vtable, t, &v);
7693 if (BINFO_VTABLE (TYPE_BINFO (t)))
7694 initialize_vtable (TYPE_BINFO (t), v);
7697 /* Initialize the vtable for BINFO with the INITS. */
7700 initialize_vtable (tree binfo, VEC(constructor_elt,gc) *inits)
7704 layout_vtable_decl (binfo, VEC_length (constructor_elt, inits));
7705 decl = get_vtbl_decl_for_binfo (binfo);
7706 initialize_artificial_var (decl, inits);
7707 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
7710 /* Build the VTT (virtual table table) for T.
7711 A class requires a VTT if it has virtual bases.
7714 1 - primary virtual pointer for complete object T
7715 2 - secondary VTTs for each direct non-virtual base of T which requires a
7717 3 - secondary virtual pointers for each direct or indirect base of T which
7718 has virtual bases or is reachable via a virtual path from T.
7719 4 - secondary VTTs for each direct or indirect virtual base of T.
7721 Secondary VTTs look like complete object VTTs without part 4. */
7729 VEC(constructor_elt,gc) *inits;
7731 /* Build up the initializers for the VTT. */
7733 index = size_zero_node;
7734 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7736 /* If we didn't need a VTT, we're done. */
7740 /* Figure out the type of the VTT. */
7741 type = build_array_of_n_type (const_ptr_type_node,
7742 VEC_length (constructor_elt, inits));
7744 /* Now, build the VTT object itself. */
7745 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7746 initialize_artificial_var (vtt, inits);
7747 /* Add the VTT to the vtables list. */
7748 DECL_CHAIN (vtt) = DECL_CHAIN (CLASSTYPE_VTABLES (t));
7749 DECL_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7754 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7755 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7756 and CHAIN the vtable pointer for this binfo after construction is
7757 complete. VALUE can also be another BINFO, in which case we recurse. */
7760 binfo_ctor_vtable (tree binfo)
7766 vt = BINFO_VTABLE (binfo);
7767 if (TREE_CODE (vt) == TREE_LIST)
7768 vt = TREE_VALUE (vt);
7769 if (TREE_CODE (vt) == TREE_BINFO)
7778 /* Data for secondary VTT initialization. */
7779 typedef struct secondary_vptr_vtt_init_data_s
7781 /* Is this the primary VTT? */
7784 /* Current index into the VTT. */
7787 /* Vector of initializers built up. */
7788 VEC(constructor_elt,gc) *inits;
7790 /* The type being constructed by this secondary VTT. */
7791 tree type_being_constructed;
7792 } secondary_vptr_vtt_init_data;
7794 /* Recursively build the VTT-initializer for BINFO (which is in the
7795 hierarchy dominated by T). INITS points to the end of the initializer
7796 list to date. INDEX is the VTT index where the next element will be
7797 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7798 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7799 for virtual bases of T. When it is not so, we build the constructor
7800 vtables for the BINFO-in-T variant. */
7803 build_vtt_inits (tree binfo, tree t, VEC(constructor_elt,gc) **inits, tree *index)
7808 secondary_vptr_vtt_init_data data;
7809 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7811 /* We only need VTTs for subobjects with virtual bases. */
7812 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7815 /* We need to use a construction vtable if this is not the primary
7819 build_ctor_vtbl_group (binfo, t);
7821 /* Record the offset in the VTT where this sub-VTT can be found. */
7822 BINFO_SUBVTT_INDEX (binfo) = *index;
7825 /* Add the address of the primary vtable for the complete object. */
7826 init = binfo_ctor_vtable (binfo);
7827 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7830 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7831 BINFO_VPTR_INDEX (binfo) = *index;
7833 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7835 /* Recursively add the secondary VTTs for non-virtual bases. */
7836 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7837 if (!BINFO_VIRTUAL_P (b))
7838 build_vtt_inits (b, t, inits, index);
7840 /* Add secondary virtual pointers for all subobjects of BINFO with
7841 either virtual bases or reachable along a virtual path, except
7842 subobjects that are non-virtual primary bases. */
7843 data.top_level_p = top_level_p;
7844 data.index = *index;
7845 data.inits = *inits;
7846 data.type_being_constructed = BINFO_TYPE (binfo);
7848 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7850 *index = data.index;
7852 /* data.inits might have grown as we added secondary virtual pointers.
7853 Make sure our caller knows about the new vector. */
7854 *inits = data.inits;
7857 /* Add the secondary VTTs for virtual bases in inheritance graph
7859 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7861 if (!BINFO_VIRTUAL_P (b))
7864 build_vtt_inits (b, t, inits, index);
7867 /* Remove the ctor vtables we created. */
7868 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7871 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7872 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7875 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7877 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7879 /* We don't care about bases that don't have vtables. */
7880 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7881 return dfs_skip_bases;
7883 /* We're only interested in proper subobjects of the type being
7885 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7888 /* We're only interested in bases with virtual bases or reachable
7889 via a virtual path from the type being constructed. */
7890 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7891 || binfo_via_virtual (binfo, data->type_being_constructed)))
7892 return dfs_skip_bases;
7894 /* We're not interested in non-virtual primary bases. */
7895 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7898 /* Record the index where this secondary vptr can be found. */
7899 if (data->top_level_p)
7901 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7902 BINFO_VPTR_INDEX (binfo) = data->index;
7904 if (BINFO_VIRTUAL_P (binfo))
7906 /* It's a primary virtual base, and this is not a
7907 construction vtable. Find the base this is primary of in
7908 the inheritance graph, and use that base's vtable
7910 while (BINFO_PRIMARY_P (binfo))
7911 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7915 /* Add the initializer for the secondary vptr itself. */
7916 CONSTRUCTOR_APPEND_ELT (data->inits, NULL_TREE, binfo_ctor_vtable (binfo));
7918 /* Advance the vtt index. */
7919 data->index = size_binop (PLUS_EXPR, data->index,
7920 TYPE_SIZE_UNIT (ptr_type_node));
7925 /* Called from build_vtt_inits via dfs_walk. After building
7926 constructor vtables and generating the sub-vtt from them, we need
7927 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7928 binfo of the base whose sub vtt was generated. */
7931 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7933 tree vtable = BINFO_VTABLE (binfo);
7935 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7936 /* If this class has no vtable, none of its bases do. */
7937 return dfs_skip_bases;
7940 /* This might be a primary base, so have no vtable in this
7944 /* If we scribbled the construction vtable vptr into BINFO, clear it
7946 if (TREE_CODE (vtable) == TREE_LIST
7947 && (TREE_PURPOSE (vtable) == (tree) data))
7948 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7953 /* Build the construction vtable group for BINFO which is in the
7954 hierarchy dominated by T. */
7957 build_ctor_vtbl_group (tree binfo, tree t)
7963 VEC(constructor_elt,gc) *v;
7965 /* See if we've already created this construction vtable group. */
7966 id = mangle_ctor_vtbl_for_type (t, binfo);
7967 if (IDENTIFIER_GLOBAL_VALUE (id))
7970 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7971 /* Build a version of VTBL (with the wrong type) for use in
7972 constructing the addresses of secondary vtables in the
7973 construction vtable group. */
7974 vtbl = build_vtable (t, id, ptr_type_node);
7975 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7978 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7979 binfo, vtbl, t, &v);
7981 /* Add the vtables for each of our virtual bases using the vbase in T
7983 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7985 vbase = TREE_CHAIN (vbase))
7989 if (!BINFO_VIRTUAL_P (vbase))
7991 b = copied_binfo (vbase, binfo);
7993 accumulate_vtbl_inits (b, vbase, binfo, vtbl, t, &v);
7996 /* Figure out the type of the construction vtable. */
7997 type = build_array_of_n_type (vtable_entry_type,
7998 VEC_length (constructor_elt, v));
8000 TREE_TYPE (vtbl) = type;
8001 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
8002 layout_decl (vtbl, 0);
8004 /* Initialize the construction vtable. */
8005 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
8006 initialize_artificial_var (vtbl, v);
8007 dump_vtable (t, binfo, vtbl);
8010 /* Add the vtbl initializers for BINFO (and its bases other than
8011 non-virtual primaries) to the list of INITS. BINFO is in the
8012 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
8013 the constructor the vtbl inits should be accumulated for. (If this
8014 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
8015 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
8016 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
8017 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
8018 but are not necessarily the same in terms of layout. */
8021 accumulate_vtbl_inits (tree binfo,
8026 VEC(constructor_elt,gc) **inits)
8030 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8032 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
8034 /* If it doesn't have a vptr, we don't do anything. */
8035 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
8038 /* If we're building a construction vtable, we're not interested in
8039 subobjects that don't require construction vtables. */
8041 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
8042 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
8045 /* Build the initializers for the BINFO-in-T vtable. */
8046 dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, vtbl, t, inits);
8048 /* Walk the BINFO and its bases. We walk in preorder so that as we
8049 initialize each vtable we can figure out at what offset the
8050 secondary vtable lies from the primary vtable. We can't use
8051 dfs_walk here because we need to iterate through bases of BINFO
8052 and RTTI_BINFO simultaneously. */
8053 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8055 /* Skip virtual bases. */
8056 if (BINFO_VIRTUAL_P (base_binfo))
8058 accumulate_vtbl_inits (base_binfo,
8059 BINFO_BASE_BINFO (orig_binfo, i),
8060 rtti_binfo, vtbl, t,
8065 /* Called from accumulate_vtbl_inits. Adds the initializers for the
8066 BINFO vtable to L. */
8069 dfs_accumulate_vtbl_inits (tree binfo,
8074 VEC(constructor_elt,gc) **l)
8076 tree vtbl = NULL_TREE;
8077 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8081 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
8083 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
8084 primary virtual base. If it is not the same primary in
8085 the hierarchy of T, we'll need to generate a ctor vtable
8086 for it, to place at its location in T. If it is the same
8087 primary, we still need a VTT entry for the vtable, but it
8088 should point to the ctor vtable for the base it is a
8089 primary for within the sub-hierarchy of RTTI_BINFO.
8091 There are three possible cases:
8093 1) We are in the same place.
8094 2) We are a primary base within a lost primary virtual base of
8096 3) We are primary to something not a base of RTTI_BINFO. */
8099 tree last = NULL_TREE;
8101 /* First, look through the bases we are primary to for RTTI_BINFO
8102 or a virtual base. */
8104 while (BINFO_PRIMARY_P (b))
8106 b = BINFO_INHERITANCE_CHAIN (b);
8108 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
8111 /* If we run out of primary links, keep looking down our
8112 inheritance chain; we might be an indirect primary. */
8113 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
8114 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
8118 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
8119 base B and it is a base of RTTI_BINFO, this is case 2. In
8120 either case, we share our vtable with LAST, i.e. the
8121 derived-most base within B of which we are a primary. */
8123 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
8124 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
8125 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
8126 binfo_ctor_vtable after everything's been set up. */
8129 /* Otherwise, this is case 3 and we get our own. */
8131 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
8134 n_inits = VEC_length (constructor_elt, *l);
8141 /* Add the initializer for this vtable. */
8142 build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
8143 &non_fn_entries, l);
8145 /* Figure out the position to which the VPTR should point. */
8146 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, orig_vtbl);
8147 index = size_binop (MULT_EXPR,
8148 TYPE_SIZE_UNIT (vtable_entry_type),
8149 size_int (non_fn_entries + n_inits));
8150 vtbl = fold_build_pointer_plus (vtbl, index);
8154 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
8155 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
8156 straighten this out. */
8157 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
8158 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
8159 /* Throw away any unneeded intializers. */
8160 VEC_truncate (constructor_elt, *l, n_inits);
8162 /* For an ordinary vtable, set BINFO_VTABLE. */
8163 BINFO_VTABLE (binfo) = vtbl;
8166 static GTY(()) tree abort_fndecl_addr;
8168 /* Construct the initializer for BINFO's virtual function table. BINFO
8169 is part of the hierarchy dominated by T. If we're building a
8170 construction vtable, the ORIG_BINFO is the binfo we should use to
8171 find the actual function pointers to put in the vtable - but they
8172 can be overridden on the path to most-derived in the graph that
8173 ORIG_BINFO belongs. Otherwise,
8174 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
8175 BINFO that should be indicated by the RTTI information in the
8176 vtable; it will be a base class of T, rather than T itself, if we
8177 are building a construction vtable.
8179 The value returned is a TREE_LIST suitable for wrapping in a
8180 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
8181 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
8182 number of non-function entries in the vtable.
8184 It might seem that this function should never be called with a
8185 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
8186 base is always subsumed by a derived class vtable. However, when
8187 we are building construction vtables, we do build vtables for
8188 primary bases; we need these while the primary base is being
8192 build_vtbl_initializer (tree binfo,
8196 int* non_fn_entries_p,
8197 VEC(constructor_elt,gc) **inits)
8203 VEC(tree,gc) *vbases;
8206 /* Initialize VID. */
8207 memset (&vid, 0, sizeof (vid));
8210 vid.rtti_binfo = rtti_binfo;
8211 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
8212 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8213 vid.generate_vcall_entries = true;
8214 /* The first vbase or vcall offset is at index -3 in the vtable. */
8215 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
8217 /* Add entries to the vtable for RTTI. */
8218 build_rtti_vtbl_entries (binfo, &vid);
8220 /* Create an array for keeping track of the functions we've
8221 processed. When we see multiple functions with the same
8222 signature, we share the vcall offsets. */
8223 vid.fns = VEC_alloc (tree, gc, 32);
8224 /* Add the vcall and vbase offset entries. */
8225 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
8227 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
8228 build_vbase_offset_vtbl_entries. */
8229 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
8230 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
8231 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
8233 /* If the target requires padding between data entries, add that now. */
8234 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
8236 int n_entries = VEC_length (constructor_elt, vid.inits);
8238 VEC_safe_grow (constructor_elt, gc, vid.inits,
8239 TARGET_VTABLE_DATA_ENTRY_DISTANCE * n_entries);
8241 /* Move data entries into their new positions and add padding
8242 after the new positions. Iterate backwards so we don't
8243 overwrite entries that we would need to process later. */
8244 for (ix = n_entries - 1;
8245 VEC_iterate (constructor_elt, vid.inits, ix, e);
8249 int new_position = (TARGET_VTABLE_DATA_ENTRY_DISTANCE * ix
8250 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE - 1));
8252 VEC_replace (constructor_elt, vid.inits, new_position, e);
8254 for (j = 1; j < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++j)
8256 constructor_elt *f = VEC_index (constructor_elt, vid.inits,
8258 f->index = NULL_TREE;
8259 f->value = build1 (NOP_EXPR, vtable_entry_type,
8265 if (non_fn_entries_p)
8266 *non_fn_entries_p = VEC_length (constructor_elt, vid.inits);
8268 /* The initializers for virtual functions were built up in reverse
8269 order. Straighten them out and add them to the running list in one
8271 jx = VEC_length (constructor_elt, *inits);
8272 VEC_safe_grow (constructor_elt, gc, *inits,
8273 (jx + VEC_length (constructor_elt, vid.inits)));
8275 for (ix = VEC_length (constructor_elt, vid.inits) - 1;
8276 VEC_iterate (constructor_elt, vid.inits, ix, e);
8278 VEC_replace (constructor_elt, *inits, jx, e);
8280 /* Go through all the ordinary virtual functions, building up
8282 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
8286 tree fn, fn_original;
8287 tree init = NULL_TREE;
8291 if (DECL_THUNK_P (fn))
8293 if (!DECL_NAME (fn))
8295 if (THUNK_ALIAS (fn))
8297 fn = THUNK_ALIAS (fn);
8300 fn_original = THUNK_TARGET (fn);
8303 /* If the only definition of this function signature along our
8304 primary base chain is from a lost primary, this vtable slot will
8305 never be used, so just zero it out. This is important to avoid
8306 requiring extra thunks which cannot be generated with the function.
8308 We first check this in update_vtable_entry_for_fn, so we handle
8309 restored primary bases properly; we also need to do it here so we
8310 zero out unused slots in ctor vtables, rather than filling them
8311 with erroneous values (though harmless, apart from relocation
8313 if (BV_LOST_PRIMARY (v))
8314 init = size_zero_node;
8318 /* Pull the offset for `this', and the function to call, out of
8320 delta = BV_DELTA (v);
8321 vcall_index = BV_VCALL_INDEX (v);
8323 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
8324 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
8326 /* You can't call an abstract virtual function; it's abstract.
8327 So, we replace these functions with __pure_virtual. */
8328 if (DECL_PURE_VIRTUAL_P (fn_original))
8331 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8333 if (abort_fndecl_addr == NULL)
8335 = fold_convert (vfunc_ptr_type_node,
8336 build_fold_addr_expr (fn));
8337 init = abort_fndecl_addr;
8342 if (!integer_zerop (delta) || vcall_index)
8344 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
8345 if (!DECL_NAME (fn))
8348 /* Take the address of the function, considering it to be of an
8349 appropriate generic type. */
8350 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8351 init = fold_convert (vfunc_ptr_type_node,
8352 build_fold_addr_expr (fn));
8356 /* And add it to the chain of initializers. */
8357 if (TARGET_VTABLE_USES_DESCRIPTORS)
8360 if (init == size_zero_node)
8361 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8362 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8364 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8366 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
8367 fn, build_int_cst (NULL_TREE, i));
8368 TREE_CONSTANT (fdesc) = 1;
8370 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, fdesc);
8374 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8378 /* Adds to vid->inits the initializers for the vbase and vcall
8379 offsets in BINFO, which is in the hierarchy dominated by T. */
8382 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
8386 /* If this is a derived class, we must first create entries
8387 corresponding to the primary base class. */
8388 b = get_primary_binfo (binfo);
8390 build_vcall_and_vbase_vtbl_entries (b, vid);
8392 /* Add the vbase entries for this base. */
8393 build_vbase_offset_vtbl_entries (binfo, vid);
8394 /* Add the vcall entries for this base. */
8395 build_vcall_offset_vtbl_entries (binfo, vid);
8398 /* Returns the initializers for the vbase offset entries in the vtable
8399 for BINFO (which is part of the class hierarchy dominated by T), in
8400 reverse order. VBASE_OFFSET_INDEX gives the vtable index
8401 where the next vbase offset will go. */
8404 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8408 tree non_primary_binfo;
8410 /* If there are no virtual baseclasses, then there is nothing to
8412 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
8417 /* We might be a primary base class. Go up the inheritance hierarchy
8418 until we find the most derived class of which we are a primary base:
8419 it is the offset of that which we need to use. */
8420 non_primary_binfo = binfo;
8421 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8425 /* If we have reached a virtual base, then it must be a primary
8426 base (possibly multi-level) of vid->binfo, or we wouldn't
8427 have called build_vcall_and_vbase_vtbl_entries for it. But it
8428 might be a lost primary, so just skip down to vid->binfo. */
8429 if (BINFO_VIRTUAL_P (non_primary_binfo))
8431 non_primary_binfo = vid->binfo;
8435 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8436 if (get_primary_binfo (b) != non_primary_binfo)
8438 non_primary_binfo = b;
8441 /* Go through the virtual bases, adding the offsets. */
8442 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
8444 vbase = TREE_CHAIN (vbase))
8449 if (!BINFO_VIRTUAL_P (vbase))
8452 /* Find the instance of this virtual base in the complete
8454 b = copied_binfo (vbase, binfo);
8456 /* If we've already got an offset for this virtual base, we
8457 don't need another one. */
8458 if (BINFO_VTABLE_PATH_MARKED (b))
8460 BINFO_VTABLE_PATH_MARKED (b) = 1;
8462 /* Figure out where we can find this vbase offset. */
8463 delta = size_binop (MULT_EXPR,
8466 TYPE_SIZE_UNIT (vtable_entry_type)));
8467 if (vid->primary_vtbl_p)
8468 BINFO_VPTR_FIELD (b) = delta;
8470 if (binfo != TYPE_BINFO (t))
8471 /* The vbase offset had better be the same. */
8472 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
8474 /* The next vbase will come at a more negative offset. */
8475 vid->index = size_binop (MINUS_EXPR, vid->index,
8476 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8478 /* The initializer is the delta from BINFO to this virtual base.
8479 The vbase offsets go in reverse inheritance-graph order, and
8480 we are walking in inheritance graph order so these end up in
8482 delta = size_diffop_loc (input_location,
8483 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
8485 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE,
8486 fold_build1_loc (input_location, NOP_EXPR,
8487 vtable_entry_type, delta));
8491 /* Adds the initializers for the vcall offset entries in the vtable
8492 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
8496 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8498 /* We only need these entries if this base is a virtual base. We
8499 compute the indices -- but do not add to the vtable -- when
8500 building the main vtable for a class. */
8501 if (binfo == TYPE_BINFO (vid->derived)
8502 || (BINFO_VIRTUAL_P (binfo)
8503 /* If BINFO is RTTI_BINFO, then (since BINFO does not
8504 correspond to VID->DERIVED), we are building a primary
8505 construction virtual table. Since this is a primary
8506 virtual table, we do not need the vcall offsets for
8508 && binfo != vid->rtti_binfo))
8510 /* We need a vcall offset for each of the virtual functions in this
8511 vtable. For example:
8513 class A { virtual void f (); };
8514 class B1 : virtual public A { virtual void f (); };
8515 class B2 : virtual public A { virtual void f (); };
8516 class C: public B1, public B2 { virtual void f (); };
8518 A C object has a primary base of B1, which has a primary base of A. A
8519 C also has a secondary base of B2, which no longer has a primary base
8520 of A. So the B2-in-C construction vtable needs a secondary vtable for
8521 A, which will adjust the A* to a B2* to call f. We have no way of
8522 knowing what (or even whether) this offset will be when we define B2,
8523 so we store this "vcall offset" in the A sub-vtable and look it up in
8524 a "virtual thunk" for B2::f.
8526 We need entries for all the functions in our primary vtable and
8527 in our non-virtual bases' secondary vtables. */
8529 /* If we are just computing the vcall indices -- but do not need
8530 the actual entries -- not that. */
8531 if (!BINFO_VIRTUAL_P (binfo))
8532 vid->generate_vcall_entries = false;
8533 /* Now, walk through the non-virtual bases, adding vcall offsets. */
8534 add_vcall_offset_vtbl_entries_r (binfo, vid);
8538 /* Build vcall offsets, starting with those for BINFO. */
8541 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
8547 /* Don't walk into virtual bases -- except, of course, for the
8548 virtual base for which we are building vcall offsets. Any
8549 primary virtual base will have already had its offsets generated
8550 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8551 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
8554 /* If BINFO has a primary base, process it first. */
8555 primary_binfo = get_primary_binfo (binfo);
8557 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
8559 /* Add BINFO itself to the list. */
8560 add_vcall_offset_vtbl_entries_1 (binfo, vid);
8562 /* Scan the non-primary bases of BINFO. */
8563 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8564 if (base_binfo != primary_binfo)
8565 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
8568 /* Called from build_vcall_offset_vtbl_entries_r. */
8571 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
8573 /* Make entries for the rest of the virtuals. */
8574 if (abi_version_at_least (2))
8578 /* The ABI requires that the methods be processed in declaration
8579 order. G++ 3.2 used the order in the vtable. */
8580 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
8582 orig_fn = DECL_CHAIN (orig_fn))
8583 if (DECL_VINDEX (orig_fn))
8584 add_vcall_offset (orig_fn, binfo, vid);
8588 tree derived_virtuals;
8591 /* If BINFO is a primary base, the most derived class which has
8592 BINFO as a primary base; otherwise, just BINFO. */
8593 tree non_primary_binfo;
8595 /* We might be a primary base class. Go up the inheritance hierarchy
8596 until we find the most derived class of which we are a primary base:
8597 it is the BINFO_VIRTUALS there that we need to consider. */
8598 non_primary_binfo = binfo;
8599 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8603 /* If we have reached a virtual base, then it must be vid->vbase,
8604 because we ignore other virtual bases in
8605 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8606 base (possibly multi-level) of vid->binfo, or we wouldn't
8607 have called build_vcall_and_vbase_vtbl_entries for it. But it
8608 might be a lost primary, so just skip down to vid->binfo. */
8609 if (BINFO_VIRTUAL_P (non_primary_binfo))
8611 gcc_assert (non_primary_binfo == vid->vbase);
8612 non_primary_binfo = vid->binfo;
8616 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8617 if (get_primary_binfo (b) != non_primary_binfo)
8619 non_primary_binfo = b;
8622 if (vid->ctor_vtbl_p)
8623 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8624 where rtti_binfo is the most derived type. */
8626 = original_binfo (non_primary_binfo, vid->rtti_binfo);
8628 for (base_virtuals = BINFO_VIRTUALS (binfo),
8629 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
8630 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
8632 base_virtuals = TREE_CHAIN (base_virtuals),
8633 derived_virtuals = TREE_CHAIN (derived_virtuals),
8634 orig_virtuals = TREE_CHAIN (orig_virtuals))
8638 /* Find the declaration that originally caused this function to
8639 be present in BINFO_TYPE (binfo). */
8640 orig_fn = BV_FN (orig_virtuals);
8642 /* When processing BINFO, we only want to generate vcall slots for
8643 function slots introduced in BINFO. So don't try to generate
8644 one if the function isn't even defined in BINFO. */
8645 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
8648 add_vcall_offset (orig_fn, binfo, vid);
8653 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8656 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
8662 /* If there is already an entry for a function with the same
8663 signature as FN, then we do not need a second vcall offset.
8664 Check the list of functions already present in the derived
8666 FOR_EACH_VEC_ELT (tree, vid->fns, i, derived_entry)
8668 if (same_signature_p (derived_entry, orig_fn)
8669 /* We only use one vcall offset for virtual destructors,
8670 even though there are two virtual table entries. */
8671 || (DECL_DESTRUCTOR_P (derived_entry)
8672 && DECL_DESTRUCTOR_P (orig_fn)))
8676 /* If we are building these vcall offsets as part of building
8677 the vtable for the most derived class, remember the vcall
8679 if (vid->binfo == TYPE_BINFO (vid->derived))
8681 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
8682 CLASSTYPE_VCALL_INDICES (vid->derived),
8684 elt->purpose = orig_fn;
8685 elt->value = vid->index;
8688 /* The next vcall offset will be found at a more negative
8690 vid->index = size_binop (MINUS_EXPR, vid->index,
8691 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8693 /* Keep track of this function. */
8694 VEC_safe_push (tree, gc, vid->fns, orig_fn);
8696 if (vid->generate_vcall_entries)
8701 /* Find the overriding function. */
8702 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8703 if (fn == error_mark_node)
8704 vcall_offset = build_zero_cst (vtable_entry_type);
8707 base = TREE_VALUE (fn);
8709 /* The vbase we're working on is a primary base of
8710 vid->binfo. But it might be a lost primary, so its
8711 BINFO_OFFSET might be wrong, so we just use the
8712 BINFO_OFFSET from vid->binfo. */
8713 vcall_offset = size_diffop_loc (input_location,
8714 BINFO_OFFSET (base),
8715 BINFO_OFFSET (vid->binfo));
8716 vcall_offset = fold_build1_loc (input_location,
8717 NOP_EXPR, vtable_entry_type,
8720 /* Add the initializer to the vtable. */
8721 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, vcall_offset);
8725 /* Return vtbl initializers for the RTTI entries corresponding to the
8726 BINFO's vtable. The RTTI entries should indicate the object given
8727 by VID->rtti_binfo. */
8730 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8738 t = BINFO_TYPE (vid->rtti_binfo);
8740 /* To find the complete object, we will first convert to our most
8741 primary base, and then add the offset in the vtbl to that value. */
8743 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8744 && !BINFO_LOST_PRIMARY_P (b))
8748 primary_base = get_primary_binfo (b);
8749 gcc_assert (BINFO_PRIMARY_P (primary_base)
8750 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8753 offset = size_diffop_loc (input_location,
8754 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8756 /* The second entry is the address of the typeinfo object. */
8758 decl = build_address (get_tinfo_decl (t));
8760 decl = integer_zero_node;
8762 /* Convert the declaration to a type that can be stored in the
8764 init = build_nop (vfunc_ptr_type_node, decl);
8765 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8767 /* Add the offset-to-top entry. It comes earlier in the vtable than
8768 the typeinfo entry. Convert the offset to look like a
8769 function pointer, so that we can put it in the vtable. */
8770 init = build_nop (vfunc_ptr_type_node, offset);
8771 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8774 #include "gt-cp-class.h"
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