| blob | a572af83f637c3d4dfec909b03e7187f1b07af18 |
1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
12 any later version.
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. */
41 /* The number of nested classes being processed. If we are not in the
42 scope of any class, this is zero. */
46 /* In order to deal with nested classes, we keep a stack of classes.
47 The topmost entry is the innermost class, and is the entry at index
48 CURRENT_CLASS_DEPTH */
51 /* The name of the class. */
52 tree name;
54 /* The _TYPE node for the class. */
55 tree type;
57 /* The access specifier pending for new declarations in the scope of
58 this class. */
59 tree access;
61 /* If were defining TYPE, the names used in this class. */
62 splay_tree names_used;
64 /* Nonzero if this class is no longer open, because of a call to
65 push_to_top_level. */
70 {
71 /* The base for which we're building initializers. */
72 tree binfo;
73 /* The type of the most-derived type. */
74 tree derived;
75 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
76 unless ctor_vtbl_p is true. */
77 tree rtti_binfo;
78 /* The negative-index vtable initializers built up so far. These
79 are in order from least negative index to most negative index. */
81 /* The binfo for the virtual base for which we're building
82 vcall offset initializers. */
83 tree vbase;
84 /* The functions in vbase for which we have already provided vcall
85 offsets. */
87 /* The vtable index of the next vcall or vbase offset. */
88 tree index;
89 /* Nonzero if we are building the initializer for the primary
90 vtable. */
92 /* Nonzero if we are building the initializer for a construction
93 vtable. */
95 /* True when adding vcall offset entries to the vtable. False when
96 merely computing the indices. */
100 /* The type of a function passed to walk_subobject_offsets. */
103 /* The stack itself. This is a dynamically resized array. The
104 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
108 /* The size of the largest empty class seen in this translation unit. */
111 /* An array of all local classes present in this translation unit, in
112 declaration order. */
202 splay_tree_key k2);
211 /* Variables shared between class.c and call.c. */
213 #ifdef GATHER_STATISTICS
221 #endif
223 /* Convert to or from a base subobject. EXPR is an expression of type
224 `A' or `A*', an expression of type `B' or `B*' is returned. To
225 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
226 the B base instance within A. To convert base A to derived B, CODE
227 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
228 In this latter case, A must not be a morally virtual base of B.
229 NONNULL is true if EXPR is known to be non-NULL (this is only
230 needed when EXPR is of pointer type). CV qualifiers are preserved
231 from EXPR. */
233 tree
235 tree expr,
236 tree binfo,
238 {
241 tree probe;
242 tree offset;
243 tree target_type;
245 tree ptr_target_type;
255 {
261 }
273 /* Nothing to do. */
277 {
281 }
284 /* This must happen before the call to save_expr. */
286 else
293 /* Do we need to look in the vtable for the real offset? */
296 /* Don't bother with the calculations inside sizeof; they'll ICE if the
297 source type is incomplete and the pointer value doesn't matter. */
299 {
304 }
306 /* Do we need to check for a null pointer? */
308 {
309 /* If we know the conversion will not actually change the value
310 of EXPR, then we can avoid testing the expression for NULL.
311 We have to avoid generating a COMPONENT_REF for a base class
312 field, because other parts of the compiler know that such
313 expressions are always non-NULL. */
315 {
316 tree class_type;
317 /* TARGET_TYPE has been extracted from BINFO, and, is
318 therefore always cv-unqualified. Extract the
319 cv-qualifiers from EXPR so that the expression returned
320 matches the input. */
322 target_type
326 }
328 }
330 /* Protect against multiple evaluation if necessary. */
334 /* Now that we've saved expr, build the real null test. */
336 {
340 }
342 /* If this is a simple base reference, express it as a COMPONENT_REF. */
344 /* We don't build base fields for empty bases, and they aren't very
345 interesting to the optimizers anyway. */
347 {
354 }
357 {
358 /* Going via virtual base V_BINFO. We need the static offset
359 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
360 V_BINFO. That offset is an entry in D_BINFO's vtable. */
361 tree v_offset;
364 {
365 /* In a base member initializer, we cannot rely on the
366 vtable being set up. We have to indirect via the
367 vtt_parm. */
368 tree t;
374 tf_warning_or_error);
375 }
376 else
378 tf_warning_or_error),
385 v_offset);
397 /* Negative fixed_type_p means this is a constructor or destructor;
398 virtual base layout is fixed in in-charge [cd]tors, but not in
399 base [cd]tors. */
403 v_offset,
406 else
408 }
410 target_type = cp_build_qualified_type
419 {
424 }
425 else
431 out:
435 integer_zero_node));
438 }
440 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
441 Perform a derived-to-base conversion by recursively building up a
442 sequence of COMPONENT_REFs to the appropriate base fields. */
444 static tree
446 {
449 tree field;
452 {
453 tree temp;
457 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
458 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
459 an lvalue in the front end; only _DECLs and _REFs are lvalues
460 in the back end. */
466 }
468 /* Recurse. */
473 /* Is this the base field created by build_base_field? */
477 {
478 /* We don't use build_class_member_access_expr here, as that
479 has unnecessary checks, and more importantly results in
480 recursive calls to dfs_walk_once. */
488 /* Mark the expression const or volatile, as appropriate.
489 Even though we've dealt with the type above, we still have
490 to mark the expression itself. */
497 }
499 /* Didn't find the base field?!? */
501 }
503 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
504 type is a class type or a pointer to a class type. In the former
505 case, TYPE is also a class type; in the latter it is another
506 pointer type. If CHECK_ACCESS is true, an error message is emitted
507 if TYPE is inaccessible. If OBJECT has pointer type, the value is
508 assumed to be non-NULL. */
510 tree
512 tsubst_flags_t complain)
513 {
514 tree binfo;
515 tree object_type;
516 base_access access;
519 {
522 }
523 else
530 access,
531 NULL);
536 }
538 /* EXPR is an expression with unqualified class type. BASE is a base
539 binfo of that class type. Returns EXPR, converted to the BASE
540 type. This function assumes that EXPR is the most derived class;
541 therefore virtual bases can be found at their static offsets. */
543 tree
545 {
546 tree expr_type;
550 {
551 tree pointer_type;
555 /* We use fold_build2 and fold_convert below to simplify the trees
556 provided to the optimizers. It is not safe to call these functions
557 when processing a template because they do not handle C++-specific
558 trees. */
561 tf_warning_or_error);
568 }
571 }
573 \f
574 tree
576 {
582 /* First, convert to the requested type. */
587 /* Second, the requested type may not be the owner of its own vptr.
588 If not, convert to the base class that owns it. We cannot use
589 convert_to_base here, because VCONTEXT may appear more than once
590 in the inheritance hierarchy of TYPE, and thus direct conversion
591 between the types may be ambiguous. Following the path back up
592 one step at a time via primary bases avoids the problem. */
596 {
599 }
602 }
604 /* Given an object INSTANCE, return an expression which yields the
605 vtable element corresponding to INDEX. There are many special
606 cases for INSTANCE which we take care of here, mainly to avoid
607 creating extra tree nodes when we don't have to. */
609 static tree
611 {
612 tree aref;
615 /* Try to figure out what a reference refers to, and
616 access its virtual function table directly. */
624 {
629 }
638 }
640 tree
642 {
646 }
648 /* Given a stable object pointer INSTANCE_PTR, return an expression which
649 yields a function pointer corresponding to vtable element INDEX. */
651 tree
653 {
654 tree aref;
657 tf_warning_or_error),
658 idx);
660 /* When using function descriptors, the address of the
661 vtable entry is treated as a function pointer. */
665 tf_warning_or_error));
667 /* Remember this as a method reference, for later devirtualization. */
671 }
673 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
674 for the given TYPE. */
676 static tree
678 {
680 }
682 /* DECL is an entity associated with TYPE, like a virtual table or an
683 implicitly generated constructor. Determine whether or not DECL
684 should have external or internal linkage at the object file
685 level. This routine does not deal with COMDAT linkage and other
686 similar complexities; it simply sets TREE_PUBLIC if it possible for
687 entities in other translation units to contain copies of DECL, in
688 the abstract. */
690 void
692 {
693 /* If TYPE involves a local class in a function with internal
694 linkage, then DECL should have internal linkage too. Other local
695 classes have no linkage -- but if their containing functions
696 have external linkage, it makes sense for DECL to have external
697 linkage too. That will allow template definitions to be merged,
698 for example. */
700 {
703 }
704 else
706 }
708 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
709 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
710 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
712 static tree
714 {
715 tree decl;
718 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
719 now to avoid confusion in mangle_decl. */
728 /* At one time the vtable info was grabbed 2 words at a time. This
729 fails on sparc unless you have 8-byte alignment. (tiemann) */
733 /* The vtable has not been defined -- yet. */
737 /* Mark the VAR_DECL node representing the vtable itself as a
738 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
739 is rather important that such things be ignored because any
740 effort to actually generate DWARF for them will run into
741 trouble when/if we encounter code like:
743 #pragma interface
744 struct S { virtual void member (); };
746 because the artificial declaration of the vtable itself (as
747 manufactured by the g++ front end) will say that the vtable is
748 a static member of `S' but only *after* the debug output for
749 the definition of `S' has already been output. This causes
750 grief because the DWARF entry for the definition of the vtable
751 will try to refer back to an earlier *declaration* of the
752 vtable as a static member of `S' and there won't be one. We
753 might be able to arrange to have the "vtable static member"
754 attached to the member list for `S' before the debug info for
755 `S' get written (which would solve the problem) but that would
756 require more intrusive changes to the g++ front end. */
760 }
762 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
763 or even complete. If this does not exist, create it. If COMPLETE is
764 nonzero, then complete the definition of it -- that will render it
765 impossible to actually build the vtable, but is useful to get at those
766 which are known to exist in the runtime. */
768 tree
770 {
771 tree decl;
780 {
783 }
786 }
788 /* Build the primary virtual function table for TYPE. If BINFO is
789 non-NULL, build the vtable starting with the initial approximation
790 that it is the same as the one which is the head of the association
791 list. Returns a nonzero value if a new vtable is actually
792 created. */
794 static int
796 {
797 tree decl;
798 tree virtuals;
803 {
805 /* We have already created a vtable for this base, so there's
806 no need to do it again. */
813 }
814 else
815 {
818 }
820 #ifdef GATHER_STATISTICS
823 #endif
825 /* Initialize the association list for this type, based
826 on our first approximation. */
831 }
833 /* Give BINFO a new virtual function table which is initialized
834 with a skeleton-copy of its original initialization. The only
835 entry that changes is the `delta' entry, so we can really
836 share a lot of structure.
838 FOR_TYPE is the most derived type which caused this table to
839 be needed.
841 Returns nonzero if we haven't met BINFO before.
843 The order in which vtables are built (by calling this function) for
844 an object must remain the same, otherwise a binary incompatibility
845 can result. */
847 static int
849 {
851 /* We already created a vtable for this base. There's no need to
852 do it again. */
855 /* Remember that we've created a vtable for this BINFO, so that we
856 don't try to do so again. */
859 /* Make fresh virtual list, so we can smash it later. */
862 /* Secondary vtables are laid out as part of the same structure as
863 the primary vtable. */
866 }
868 /* Create a new vtable for BINFO which is the hierarchy dominated by
869 T. Return nonzero if we actually created a new vtable. */
871 static int
873 {
875 /* In this case, it is *type*'s vtable we are modifying. We start
876 with the approximation that its vtable is that of the
877 immediate base class. */
879 else
880 /* This is our very own copy of `basetype' to play with. Later,
881 we will fill in all the virtual functions that override the
882 virtual functions in these base classes which are not defined
883 by the current type. */
885 }
887 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
888 (which is in the hierarchy dominated by T) list FNDECL as its
889 BV_FN. DELTA is the required constant adjustment from the `this'
890 pointer where the vtable entry appears to the `this' required when
891 the function is actually called. */
893 static void
895 tree binfo,
896 tree fndecl,
897 tree delta,
899 {
900 tree v;
906 {
907 /* We need a new vtable for BINFO. */
909 {
910 /* If we really did make a new vtable, we also made a copy
911 of the BINFO_VIRTUALS list. Now, we have to find the
912 corresponding entry in that list. */
917 }
922 }
923 }
925 \f
926 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
927 the USING_DECL naming METHOD. Returns true if the method could be
928 added to the method vec. */
930 bool
932 {
934 tree overload;
940 tree current_fns;
941 tree fns;
954 {
955 /* Make a new method vector. We start with 8 entries. We must
956 allocate at least two (for constructors and destructors), and
957 we're going to end up with an assignment operator at some
958 point as well. */
960 /* Create slots for constructors and destructors. */
964 }
966 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
969 /* Constructors and destructors go in special slots. */
973 {
977 {
983 type);
984 }
985 }
986 else
987 {
988 tree m;
991 /* See if we already have an entry with this name. */
995 {
998 {
1003 }
1007 {
1010 }
1015 }
1016 }
1019 /* Check to see if we've already got this method. */
1021 {
1023 tree fn_type;
1024 tree method_type;
1025 tree parms1;
1026 tree parms2;
1031 /* [over.load] Member function declarations with the
1032 same name and the same parameter types cannot be
1033 overloaded if any of them is a static member
1034 function declaration.
1036 [namespace.udecl] When a using-declaration brings names
1037 from a base class into a derived class scope, member
1038 functions in the derived class override and/or hide member
1039 functions with the same name and parameter types in a base
1040 class (rather than conflicting). */
1046 /* Compare the quals on the 'this' parm. Don't compare
1047 the whole types, as used functions are treated as
1048 coming from the using class in overload resolution. */
1057 /* For templates, the return type and template parameters
1058 must be identical. */
1075 {
1077 {
1079 /* Defer to the local function. */
1083 else
1085 using_decl);
1086 }
1087 else
1088 {
1091 }
1093 /* We don't call duplicate_decls here to merge the
1094 declarations because that will confuse things if the
1095 methods have inline definitions. In particular, we
1096 will crash while processing the definitions. */
1098 }
1099 }
1101 /* A class should never have more than one destructor. */
1105 /* Add the new binding. */
1114 {
1117 /* We only expect to add few methods in the COMPLETE_P case, so
1118 just make room for one more method in that case. */
1121 else
1127 else
1129 }
1130 else
1131 /* Replace the current slot. */
1134 }
1136 /* Subroutines of finish_struct. */
1138 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1139 legit, otherwise return 0. */
1141 static int
1143 {
1144 tree elem;
1153 {
1155 {
1159 else
1162 }
1163 else
1164 {
1165 /* They're changing the access to the same thing they changed
1166 it to before. That's OK. */
1167 ;
1168 }
1169 }
1170 else
1171 {
1175 }
1177 }
1179 /* Process the USING_DECL, which is a member of T. */
1181 static void
1183 {
1186 tree access
1191 tree old_value;
1197 {
1203 else
1205 }
1213 ;
1215 {
1217 /* It's OK to use functions from a base when there are functions with
1219 else
1220 {
1225 }
1226 }
1228 {
1232 }
1234 /* Make type T see field decl FDECL with access ACCESS. */
1237 {
1240 }
1241 else
1243 }
1244 \f
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. */
1249 static void
1255 {
1258 tree base_binfo;
1259 tree binfo;
1271 {
1276 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1277 here because the case of virtual functions but non-virtual
1278 dtor is handled in finish_struct_1. */
1283 /* If the base class doesn't have copy constructors or
1284 assignment operators that take const references, then the
1285 derived class cannot have such a member automatically
1286 generated. */
1299 /* A virtual base does not effect nearly emptiness. */
1300 ;
1302 {
1304 /* And if there is more than one nearly empty base, then the
1305 derived class is not nearly empty either. */
1307 else
1308 /* Remember we've seen one. */
1310 }
1312 /* If the base class is not empty or nearly empty, then this
1313 class cannot be nearly empty. */
1316 /* A lot of properties from the bases also apply to the derived
1317 class. */
1335 /* A standard-layout class is a class that:
1336 ...
1337 * has no non-standard-layout base classes, */
1340 {
1341 tree basefield;
1342 /* ...has no base classes of the same type as the first non-static
1343 data member... */
1345 && (same_type_ignoring_top_level_qualifiers_p
1348 else
1349 /* ...either has no non-static data members in the most-derived
1350 class and at most one base class with non-static data
1351 members, or has no base classes with non-static data
1352 members */
1356 {
1359 else
1362 }
1363 }
1364 }
1365 }
1367 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1368 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1369 that have had a nearly-empty virtual primary base stolen by some
1370 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1371 T. */
1373 static void
1375 {
1379 tree base_binfo;
1381 /* Determine the primary bases of our bases. */
1384 {
1387 /* See if we're the non-virtual primary of our inheritance
1388 chain. */
1390 {
1397 /* We are the primary binfo. */
1399 }
1400 /* Determine if we have a virtual primary base, and mark it so.
1401 */
1403 {
1407 /* Someone already claimed this base. */
1409 else
1410 {
1411 tree delta;
1416 /* A virtual binfo might have been copied from within
1417 another hierarchy. As we're about to use it as a
1418 primary base, make sure the offsets match. */
1426 }
1427 }
1428 }
1430 /* First look for a dynamic direct non-virtual base. */
1432 {
1436 {
1439 }
1440 }
1442 /* A "nearly-empty" virtual base class can be the primary base
1443 class, if no non-virtual polymorphic base can be found. Look for
1444 a nearly-empty virtual dynamic base that is not already a primary
1445 base of something in the hierarchy. If there is no such base,
1446 just pick the first nearly-empty virtual base. */
1452 {
1454 {
1455 /* Found one that is not primary. */
1458 }
1460 /* Remember the first candidate. */
1462 }
1464 found:
1465 /* If we've got a primary base, use it. */
1467 {
1472 /* We are stealing a primary base. */
1476 {
1477 tree delta;
1480 /* A virtual binfo might have been copied from within
1481 another hierarchy. As we're about to use it as a primary
1482 base, make sure the offsets match. */
1487 }
1494 }
1495 }
1497 /* Update the variant types of T. */
1499 void
1501 {
1502 tree variants;
1508 variants;
1510 {
1511 /* These fields are in the _TYPE part of the node, not in
1512 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1522 /* Copy whatever these are holding today. */
1527 /* All variants of a class have the same attributes. */
1529 }
1530 }
1532 \f
1533 /* Set memoizing fields and bits of T (and its variants) for later
1534 use. */
1536 static void
1538 {
1539 /* Fix up variants (if any). */
1543 /* For a class w/o baseclasses, 'finish_struct' has set
1544 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1545 Similarly for a class whose base classes do not have vtables.
1546 When neither of these is true, we might have removed abstract
1547 virtuals (by providing a definition), added some (by declaring
1548 new ones), or redeclared ones from a base class. We need to
1549 recalculate what's really an abstract virtual at this point (by
1550 looking in the vtables). */
1553 /* If this type has a copy constructor or a destructor, force its
1554 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1555 nonzero. This will cause it to be passed by invisible reference
1556 and prevent it from being returned in a register. */
1559 {
1560 tree variants;
1563 {
1566 }
1567 }
1568 }
1570 /* Issue warnings about T having private constructors, but no friends,
1571 and so forth.
1573 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1574 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1575 non-private static member functions. */
1577 static void
1579 {
1582 tree fn;
1585 /* If the class has friends, those entities might create and
1586 access instances, so we should not warn. */
1589 /* We will have warned when the template was declared; there's
1590 no need to warn on every instantiation. */
1592 /* There's no reason to even consider warning about this
1593 class. */
1596 /* We only issue one warning, if more than one applies, because
1597 otherwise, on code like:
1599 class A {
1600 // Oops - forgot `public:'
1601 A();
1602 A(const A&);
1603 ~A();
1604 };
1606 we warn several times about essentially the same problem. */
1608 /* Check to see if all (non-constructor, non-destructor) member
1609 functions are private. (Since there are no friends or
1610 non-private statics, we can't ever call any of the private member
1611 functions.) */
1613 /* We're not interested in compiler-generated methods; they don't
1614 provide any way to call private members. */
1616 {
1618 {
1620 /* A non-private static member function is just like a
1621 friend; it can create and invoke private member
1622 functions, and be accessed without a class
1623 instance. */
1627 /* Keep searching for a static member function. */
1628 }
1631 }
1634 {
1635 /* There are no non-private methods, and there's at least one
1636 private member function that isn't a constructor or
1637 destructor. (If all the private members are
1638 constructors/destructors we want to use the code below that
1639 issues error messages specifically referring to
1640 constructors/destructors.) */
1646 {
1649 }
1651 {
1655 }
1656 }
1658 /* Even if some of the member functions are non-private, the class
1659 won't be useful for much if all the constructors or destructors
1660 are private: such an object can never be created or destroyed. */
1663 {
1666 t);
1668 }
1670 /* Warn about classes that have private constructors and no friends. */
1672 /* Implicitly generated constructors are always public. */
1675 {
1678 /* If a non-template class does not define a copy
1679 constructor, one is defined for it, enabling it to avoid
1680 this warning. For a template class, this does not
1681 happen, and so we would normally get a warning on:
1683 template <class T> class C { private: C(); };
1685 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1686 complete non-template or fully instantiated classes have this
1687 flag set. */
1690 else
1692 {
1694 /* Ideally, we wouldn't count copy constructors (or, in
1695 fact, any constructor that takes an argument of the
1696 class type as a parameter) because such things cannot
1697 be used to construct an instance of the class unless
1698 you already have one. But, for now at least, we're
1699 more generous. */
1701 {
1704 }
1705 }
1708 {
1711 t);
1713 }
1714 }
1715 }
1718 gt_pointer_operator new_value;
1722 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1724 static int
1726 {
1739 }
1741 /* This routine compares two fields like method_name_cmp but using the
1742 pointer operator in resort_field_decl_data. */
1744 static int
1746 {
1755 {
1762 }
1764 }
1766 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1768 void
1771 gt_pointer_operator new_value,
1773 {
1777 tree fn;
1779 /* The type conversion ops have to live at the front of the vec, so we
1780 can't sort them. */
1788 {
1792 resort_method_name_cmp);
1793 }
1794 }
1796 /* Warn about duplicate methods in fn_fields.
1798 Sort methods that are not special (i.e., constructors, destructors,
1799 and type conversion operators) so that we can find them faster in
1800 search. */
1802 static void
1804 {
1805 tree fn_fields;
1815 /* Clear DECL_IN_AGGR_P for all functions. */
1820 /* Issue warnings about private constructors and such. If there are
1821 no methods, then some public defaults are generated. */
1824 /* The type conversion ops have to live at the front of the vec, so we
1825 can't sort them. */
1834 }
1836 /* Make BINFO's vtable have N entries, including RTTI entries,
1837 vbase and vcall offsets, etc. Set its type and call the back end
1838 to lay it out. */
1840 static void
1842 {
1843 tree atype;
1844 tree vtable;
1850 /* We may have to grow the vtable. */
1853 {
1857 }
1858 }
1860 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1861 have the same signature. */
1863 int
1865 {
1866 /* One destructor overrides another if they are the same kind of
1867 destructor. */
1871 /* But a non-destructor never overrides a destructor, nor vice
1872 versa, nor do different kinds of destructors override
1873 one-another. For example, a complete object destructor does not
1874 override a deleting destructor. */
1883 {
1891 }
1893 }
1895 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1896 subobject. */
1898 static bool
1900 {
1901 tree probe;
1904 {
1908 /* If we meet a virtual base, we can't follow the inheritance
1909 any more. See if the complete type of DERIVED contains
1910 such a virtual base. */
1913 }
1915 }
1918 /* The function for which we are trying to find a final overrider. */
1919 tree fn;
1920 /* The base class in which the function was declared. */
1921 tree declaring_base;
1922 /* The candidate overriders. */
1923 tree candidates;
1924 /* Path to most derived. */
1928 /* Add the overrider along the current path to FFOD->CANDIDATES.
1929 Returns true if an overrider was found; false otherwise. */
1931 static bool
1935 {
1936 tree method;
1938 /* If BINFO is not the most derived type, try a more derived class.
1939 A definition there will overrider a definition here. */
1941 {
1942 depth--;
1946 }
1950 {
1953 /* Remove any candidates overridden by this new function. */
1955 {
1956 /* If *CANDIDATE overrides METHOD, then METHOD
1957 cannot override anything else on the list. */
1960 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1963 else
1965 }
1967 /* Add the new function. */
1970 }
1973 }
1975 /* Called from find_final_overrider via dfs_walk. */
1977 static tree
1979 {
1987 }
1989 static tree
1991 {
1996 }
1998 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1999 FN and whose TREE_VALUE is the binfo for the base where the
2000 overriding occurs. BINFO (in the hierarchy dominated by the binfo
2001 DERIVED) is the base object in which FN is declared. */
2003 static tree
2005 {
2006 find_final_overrider_data ffod;
2008 /* Getting this right is a little tricky. This is valid:
2010 struct S { virtual void f (); };
2011 struct T { virtual void f (); };
2012 struct U : public S, public T { };
2014 even though calling `f' in `U' is ambiguous. But,
2016 struct R { virtual void f(); };
2017 struct S : virtual public R { virtual void f (); };
2018 struct T : virtual public R { virtual void f (); };
2019 struct U : public S, public T { };
2021 is not -- there's no way to decide whether to put `S::f' or
2022 `T::f' in the vtable for `R'.
2024 The solution is to look at all paths to BINFO. If we find
2025 different overriders along any two, then there is a problem. */
2029 /* Determine the depth of the hierarchy. */
2040 /* If there was no winner, issue an error message. */
2045 }
2047 /* Return the index of the vcall offset for FN when TYPE is used as a
2048 virtual base. */
2050 static tree
2052 {
2054 tree_pair_p p;
2062 /* There should always be an appropriate index. */
2064 }
2066 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2067 dominated by T. FN is the old function; VIRTUALS points to the
2068 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2069 of that entry in the list. */
2071 static void
2074 {
2075 tree b;
2076 tree overrider;
2077 tree delta;
2078 tree virtual_base;
2079 tree first_defn;
2085 /* Find the nearest primary base (possibly binfo itself) which defines
2086 this function; this is the class the caller will convert to when
2087 calling FN through BINFO. */
2089 {
2094 /* The nearest definition is from a lost primary. */
2097 }
2100 /* Find the final overrider. */
2103 {
2106 }
2109 /* Check for adjusting covariant return types. */
2117 /* If the overrider is invalid, don't even try. */
2119 {
2120 /* If FN is a covariant thunk, we must figure out the adjustment
2121 to the final base FN was converting to. As OVERRIDER_TARGET might
2122 also be converting to the return type of FN, we have to
2123 combine the two conversions here. */
2130 {
2134 }
2135 else
2139 /* Find the equivalent binfo within the return type of the
2140 overriding function. We will want the vbase offset from
2141 there. */
2143 over_return);
2146 {
2147 /* There was no existing virtual thunk (which takes
2148 precedence). So find the binfo of the base function's
2149 return type within the overriding function's return type.
2150 We cannot call lookup base here, because we're inside a
2151 dfs_walk, and will therefore clobber the BINFO_MARKED
2152 flags. Fortunately we know the covariancy is valid (it
2153 has already been checked), so we can just iterate along
2154 the binfos, which have been chained in inheritance graph
2155 order. Of course it is lame that we have to repeat the
2156 search here anyway -- we should really be caching pieces
2157 of the vtable and avoiding this repeated work. */
2160 /* Find the base binfo within the overriding function's
2161 return type. We will always find a thunk_binfo, except
2162 when the covariancy is invalid (which we will have
2163 already diagnosed). */
2166 thunk_binfo;
2172 /* See if virtual inheritance is involved. */
2174 virtual_offset;
2181 {
2185 {
2186 /* We convert via virtual base. Adjust the fixed
2187 offset to be from there. */
2188 offset =
2192 }
2194 /* There was an existing fixed offset, this must be
2195 from the base just converted to, and the base the
2196 FN was thunking to. */
2198 else
2200 }
2201 }
2204 /* Replace the overriding function with a covariant thunk. We
2205 will emit the overriding function in its own slot as
2206 well. */
2209 }
2210 else
2214 /* If we need a covariant thunk, then we may need to adjust first_defn.
2215 The ABI specifies that the thunks emitted with a function are
2216 determined by which bases the function overrides, so we need to be
2217 sure that we're using a thunk for some overridden base; even if we
2218 know that the necessary this adjustment is zero, there may not be an
2219 appropriate zero-this-adjusment thunk for us to use since thunks for
2220 overriding virtual bases always use the vcall offset.
2222 Furthermore, just choosing any base that overrides this function isn't
2223 quite right, as this slot won't be used for calls through a type that
2224 puts a covariant thunk here. Calling the function through such a type
2225 will use a different slot, and that slot is the one that determines
2226 the thunk emitted for that base.
2228 So, keep looking until we find the base that we're really overriding
2229 in this slot: the nearest primary base that doesn't use a covariant
2230 thunk in this slot. */
2232 {
2234 /* We already know that the overrider needs a covariant thunk. */
2237 {
2244 }
2246 }
2248 /* Assume that we will produce a thunk that convert all the way to
2249 the final overrider, and not to an intermediate virtual base. */
2252 /* See if we can convert to an intermediate virtual base first, and then
2253 use the vcall offset located there to finish the conversion. */
2255 {
2256 /* If we find the final overrider, then we can stop
2257 walking. */
2262 /* If we find a virtual base, and we haven't yet found the
2263 overrider, then there is a virtual base between the
2264 declaring base (first_defn) and the final overrider. */
2266 {
2269 }
2270 }
2272 /* Compute the constant adjustment to the `this' pointer. The
2273 `this' pointer, when this function is called, will point at BINFO
2274 (or one of its primary bases, which are at the same offset). */
2276 /* The `this' pointer needs to be adjusted from the declaration to
2277 the nearest virtual base. */
2282 /* If the nearest definition is in a lost primary, we don't need an
2283 entry in our vtable. Except possibly in a constructor vtable,
2284 if we happen to get our primary back. In that case, the offset
2285 will be zero, as it will be a primary base. */
2287 else
2288 /* The `this' pointer needs to be adjusted from pointing to
2289 BINFO to pointing at the base where the final overrider
2290 appears. */
2301 else
2306 }
2308 /* Called from modify_all_vtables via dfs_walk. */
2310 static tree
2312 {
2314 tree virtuals;
2315 tree old_virtuals;
2319 /* A base without a vtable needs no modification, and its bases
2320 are uninteresting. */
2325 /* Don't do the primary vtable, if it's new. */
2329 /* There's no need to modify the vtable for a non-virtual primary
2330 base; we're not going to use that vtable anyhow. We do still
2331 need to do this for virtual primary bases, as they could become
2332 non-primary in a construction vtable. */
2337 /* Now, go through each of the virtual functions in the virtual
2338 function table for BINFO. Find the final overrider, and update
2339 the BINFO_VIRTUALS list appropriately. */
2342 virtuals;
2346 binfo,
2351 }
2353 /* Update all of the primary and secondary vtables for T. Create new
2354 vtables as required, and initialize their RTTI information. Each
2355 of the functions in VIRTUALS is declared in T and may override a
2356 virtual function from a base class; find and modify the appropriate
2357 entries to point to the overriding functions. Returns a list, in
2358 declaration order, of the virtual functions that are declared in T,
2359 but do not appear in the primary base class vtable, and which
2360 should therefore be appended to the end of the vtable for T. */
2362 static tree
2364 {
2368 /* Update all of the vtables. */
2371 /* Add virtual functions not already in our primary vtable. These
2372 will be both those introduced by this class, and those overridden
2373 from secondary bases. It does not include virtuals merely
2374 inherited from secondary bases. */
2376 {
2381 {
2382 /* We don't need to adjust the `this' pointer when
2383 calling this function. */
2387 /* This is a function not already in our vtable. Keep it. */
2389 }
2390 else
2391 /* We've already got an entry for this function. Skip it. */
2393 }
2396 }
2398 /* Get the base virtual function declarations in T that have the
2399 indicated NAME. */
2401 static tree
2403 {
2404 tree methods;
2409 /* Find virtual functions in T with the indicated NAME. */
2413 methods;
2415 {
2421 }
2427 {
2430 base_fndecls);
2431 }
2434 }
2436 /* If this declaration supersedes the declaration of
2437 a method declared virtual in the base class, then
2438 mark this field as being virtual as well. */
2440 void
2442 {
2444 /* In [temp.mem] we have:
2446 A specialization of a member function template does not
2447 override a virtual function from a base class. */
2454 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2455 the error_mark_node so that we know it is an overriding
2456 function. */
2460 {
2464 }
2465 }
2467 /* Warn about hidden virtual functions that are not overridden in t.
2468 We know that constructors and destructors don't apply. */
2470 static void
2472 {
2474 tree fns;
2477 /* We go through each separately named virtual function. */
2481 {
2482 tree fn;
2483 tree name;
2484 tree fndecl;
2485 tree base_fndecls;
2486 tree base_binfo;
2487 tree binfo;
2490 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2491 have the same name. Figure out what name that is. */
2493 /* There are no possibly hidden functions yet. */
2495 /* Iterate through all of the base classes looking for possibly
2496 hidden functions. */
2499 {
2502 base_fndecls);
2503 }
2505 /* If there are no functions to hide, continue. */
2509 /* Remove any overridden functions. */
2511 {
2514 {
2518 /* If the method from the base class has the same
2519 signature as the method from the derived class, it
2520 has been overridden. */
2523 else
2525 }
2526 }
2528 /* Now give a warning for all base functions without overriders,
2529 as they are hidden. */
2531 {
2532 /* Here we know it is a hider, and no overrider exists. */
2536 }
2537 }
2538 }
2540 /* Check for things that are invalid. There are probably plenty of other
2541 things we should check for also. */
2543 static void
2545 {
2546 tree field;
2549 {
2557 {
2561 {
2562 /* We're generally only interested in entities the user
2563 declared, but we also find nested classes by noticing
2564 the TYPE_DECL that we create implicitly. You're
2565 allowed to put one anonymous union inside another,
2566 though, so we explicitly tolerate that. We use
2567 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2568 we also allow unnamed types used for defining fields. */
2575 {
2579 else
2583 }
2586 {
2589 else
2591 }
2593 {
2596 else
2598 }
2602 }
2603 }
2604 }
2605 }
2607 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2608 will be used later during class template instantiation.
2609 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2610 a non-static member data (FIELD_DECL), a member function
2611 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2612 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2613 When FRIEND_P is nonzero, T is either a friend class
2614 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2615 (FUNCTION_DECL, TEMPLATE_DECL). */
2617 void
2619 {
2620 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2625 }
2627 /* Create default constructors, assignment operators, and so forth for
2628 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2629 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2630 the class cannot have a default constructor, copy constructor
2631 taking a const reference argument, or an assignment operator taking
2632 a const reference, respectively. */
2634 static void
2640 {
2641 /* Destructor. */
2643 {
2644 /* In general, we create destructors lazily. */
2649 /* But if this is a Java class, any non-trivial destructor is
2650 invalid, even if compiler-generated. Therefore, if the
2651 destructor is non-trivial we create it now. */
2653 }
2655 /* [class.ctor]
2657 If there is no user-declared constructor for a class, a default
2658 constructor is implicitly declared. */
2660 {
2663 }
2665 /* [class.ctor]
2667 If a class definition does not explicitly declare a copy
2668 constructor, one is declared implicitly. */
2671 {
2677 }
2679 /* If there is no assignment operator, one will be created if and
2680 when it is needed. For now, just record whether or not the type
2681 of the parameter to the assignment operator will be a const or
2682 non-const reference. */
2685 {
2691 }
2693 /* If a base or member type has a user-declared constructor or operator=,
2694 we need to declare ours now to avoid issues with circular lazy
2695 declarations (cpp0x/implicit6.C). */
2697 {
2704 }
2706 {
2711 }
2713 /* We can't be lazy about declaring functions that might override
2714 a virtual function from a base class. */
2719 {
2721 tree base_binfo;
2725 {
2726 tree bv;
2728 {
2731 {
2736 }
2740 }
2741 }
2742 }
2743 }
2745 /* Subroutine of finish_struct_1. Recursively count the number of fields
2746 in TYPE, including anonymous union members. */
2748 static int
2750 {
2751 tree x;
2754 {
2757 else
2759 }
2761 }
2763 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2764 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2766 static int
2768 {
2769 tree x;
2771 {
2774 else
2776 }
2778 }
2780 /* FIELD is a bit-field. We are finishing the processing for its
2781 enclosing type. Issue any appropriate messages and set appropriate
2782 flags. Returns false if an error has been diagnosed. */
2784 static bool
2786 {
2788 tree w;
2790 /* Extract the declared width of the bitfield, which has been
2791 temporarily stashed in DECL_INITIAL. */
2794 /* Remove the bit-field width indicator so that the rest of the
2795 compiler does not treat that value as an initializer. */
2798 /* Detect invalid bit-field type. */
2800 {
2803 }
2804 else
2805 {
2806 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2809 /* detect invalid field size. */
2813 {
2816 }
2818 {
2821 }
2823 {
2826 }
2835 }
2838 {
2842 }
2843 else
2844 {
2845 /* Non-bit-fields are aligned for their type. */
2849 }
2850 }
2852 /* FIELD is a non bit-field. We are finishing the processing for its
2853 enclosing type T. Issue any appropriate messages and set appropriate
2854 flags. */
2856 static void
2858 tree t,
2864 {
2867 /* In C++98 an anonymous union cannot contain any fields which would change
2868 the settings of CANT_HAVE_CONST_CTOR and friends. */
2870 ;
2871 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2872 structs. So, we recurse through their fields here. */
2874 {
2875 tree fields;
2882 }
2883 /* Check members with class type for constructors, destructors,
2884 etc. */
2886 {
2887 /* Never let anything with uninheritable virtuals
2888 make it through without complaint. */
2892 {
2897 field);
2902 field);
2904 {
2908 }
2909 }
2910 else
2911 {
2924 }
2938 }
2940 {
2941 /* `build_class_init_list' does not recognize
2942 non-FIELD_DECLs. */
2946 }
2947 }
2949 /* Check the data members (both static and non-static), class-scoped
2950 typedefs, etc., appearing in the declaration of T. Issue
2951 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2952 declaration order) of access declarations; each TREE_VALUE in this
2953 list is a USING_DECL.
2955 In addition, set the following flags:
2957 EMPTY_P
2958 The class is empty, i.e., contains no non-static data members.
2960 CANT_HAVE_CONST_CTOR_P
2961 This class cannot have an implicitly generated copy constructor
2962 taking a const reference.
2964 CANT_HAVE_CONST_ASN_REF
2965 This class cannot have an implicitly generated assignment
2966 operator taking a const reference.
2968 All of these flags should be initialized before calling this
2969 function.
2971 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2972 fields can be added by adding to this chain. */
2974 static void
2980 {
2988 /* Assume there are no access declarations. */
2990 /* Assume this class has no pointer members. */
2992 /* Assume none of the members of this class have default
2993 initializations. */
2997 {
3005 {
3006 /* Prune the access declaration from the list of fields. */
3009 /* Save the access declarations for our caller. */
3012 /* Since we've reset *FIELD there's no reason to skip to the
3013 next field. */
3016 }
3022 /* If we've gotten this far, it's a data member, possibly static,
3023 or an enumerator. */
3026 /* When this goes into scope, it will be a non-local reference. */
3030 {
3031 /* [class.union]
3033 If a union contains a static data member, or a member of
3034 reference type, the program is ill-formed. */
3036 {
3039 }
3041 {
3046 }
3047 }
3049 /* Perform error checking that did not get done in
3050 grokdeclarator. */
3052 {
3056 }
3058 {
3062 }
3070 /* Now it can only be a FIELD_DECL. */
3075 /* A standard-layout class is a class that:
3076 ...
3077 has the same access control (Clause 11) for all non-static data members,
3078 ... */
3085 /* If this is of reference type, check if it needs an init. */
3087 {
3093 /* ARM $12.6.2: [A member initializer list] (or, for an
3094 aggregate, initialization by a brace-enclosed list) is the
3095 only way to initialize nonstatic const and reference
3096 members. */
3099 }
3104 {
3106 {
3107 warning
3110 x);
3112 }
3116 }
3119 /* We don't treat zero-width bitfields as making a class
3120 non-empty. */
3121 ;
3122 else
3123 {
3124 /* The class is non-empty. */
3126 /* The class is not even nearly empty. */
3128 /* If one of the data members contains an empty class,
3129 so does T. */
3133 }
3135 /* This is used by -Weffc++ (see below). Warn only for pointers
3136 to members which might hold dynamic memory. So do not warn
3137 for pointers to functions or pointers to members. */
3144 {
3149 }
3155 /* DR 148 now allows pointers to members (which are POD themselves),
3156 to be allowed in POD structs. */
3165 /* We set DECL_C_BIT_FIELD in grokbitfield.
3166 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3169 cant_have_const_ctor_p,
3170 no_const_asn_ref_p,
3172 cant_have_lazy_ctor_p,
3173 cant_have_lazy_opeq_p);
3175 /* If any field is const, the structure type is pseudo-const. */
3177 {
3182 /* ARM $12.6.2: [A member initializer list] (or, for an
3183 aggregate, initialization by a brace-enclosed list) is the
3184 only way to initialize nonstatic const and reference
3185 members. */
3188 }
3189 /* A field that is pseudo-const makes the structure likewise. */
3191 {
3196 }
3198 /* Core issue 80: A nonstatic data member is required to have a
3199 different name from the class iff the class has a
3200 user-declared constructor. */
3204 }
3206 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3207 it should also define a copy constructor and an assignment operator to
3208 implement the correct copy semantic (deep vs shallow, etc.). As it is
3209 not feasible to check whether the constructors do allocate dynamic memory
3210 and store it within members, we approximate the warning like this:
3212 -- Warn only if there are members which are pointers
3213 -- Warn only if there is a non-trivial constructor (otherwise,
3214 there cannot be memory allocated).
3215 -- Warn only if there is a non-trivial destructor. We assume that the
3216 user at least implemented the cleanup correctly, and a destructor
3217 is needed to free dynamic memory.
3219 This seems enough for practical purposes. */
3221 && has_pointers
3225 {
3229 {
3234 }
3238 }
3240 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3244 /* Check anonymous struct/anonymous union fields. */
3247 /* We've built up the list of access declarations in reverse order.
3248 Fix that now. */
3250 }
3252 /* If TYPE is an empty class type, records its OFFSET in the table of
3253 OFFSETS. */
3255 static int
3257 {
3258 splay_tree_node n;
3263 /* Record the location of this empty object in OFFSETS. */
3271 type,
3275 }
3277 /* Returns nonzero if TYPE is an empty class type and there is
3278 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3280 static int
3282 {
3283 splay_tree_node n;
3284 tree t;
3289 /* Record the location of this empty object in OFFSETS. */
3299 }
3301 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3302 F for every subobject, passing it the type, offset, and table of
3303 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3304 be traversed.
3306 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3307 than MAX_OFFSET will not be walked.
3309 If F returns a nonzero value, the traversal ceases, and that value
3310 is returned. Otherwise, returns zero. */
3312 static int
3314 subobject_offset_fn f,
3315 tree offset,
3316 splay_tree offsets,
3317 tree max_offset,
3319 {
3323 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3324 stop. */
3332 {
3336 }
3339 {
3340 tree field;
3341 tree binfo;
3344 /* Avoid recursing into objects that are not interesting. */
3348 /* Record the location of TYPE. */
3353 /* Iterate through the direct base classes of TYPE. */
3357 {
3358 tree binfo_offset;
3371 offset,
3373 else
3374 {
3375 tree orig_binfo;
3376 /* We cannot rely on BINFO_OFFSET being set for the base
3377 class yet, but the offsets for direct non-virtual
3378 bases can be calculated by going back to the TYPE. */
3381 offset,
3383 }
3386 f,
3387 binfo_offset,
3388 offsets,
3389 max_offset,
3394 }
3397 {
3401 /* Iterate through the virtual base classes of TYPE. In G++
3402 3.2, we included virtual bases in the direct base class
3403 loop above, which results in incorrect results; the
3404 correct offsets for virtual bases are only known when
3405 working with the most derived type. */
3409 {
3411 f,
3413 offset,
3415 offsets,
3416 max_offset,
3420 }
3421 else
3422 {
3423 /* We still have to walk the primary base, if it is
3424 virtual. (If it is non-virtual, then it was walked
3425 above.) */
3431 {
3432 r = (walk_subobject_offsets
3437 }
3438 }
3439 }
3441 /* Iterate through the fields of TYPE. */
3444 {
3445 tree field_offset;
3449 else
3450 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3454 f,
3456 offset,
3457 field_offset),
3458 offsets,
3459 max_offset,
3463 }
3464 }
3466 {
3469 tree index;
3471 /* Avoid recursing into objects that are not interesting. */
3476 /* Step through each of the elements in the array. */
3478 /* G++ 3.2 had an off-by-one error here. */
3483 {
3485 f,
3486 offset,
3487 offsets,
3488 max_offset,
3494 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3495 there's no point in iterating through the remaining
3496 elements of the array. */
3499 }
3500 }
3503 }
3505 /* Record all of the empty subobjects of TYPE (either a type or a
3506 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3507 is being placed at OFFSET; otherwise, it is a base class that is
3508 being placed at OFFSET. */
3510 static void
3512 tree offset,
3513 splay_tree offsets,
3515 {
3516 tree max_offset;
3517 /* If recording subobjects for a non-static data member or a
3518 non-empty base class , we do not need to record offsets beyond
3519 the size of the biggest empty class. Additional data members
3520 will go at the end of the class. Additional base classes will go
3521 either at offset zero (if empty, in which case they cannot
3522 overlap with offsets past the size of the biggest empty class) or
3523 at the end of the class.
3525 However, if we are placing an empty base class, then we must record
3526 all offsets, as either the empty class is at offset zero (where
3527 other empty classes might later be placed) or at the end of the
3528 class (where other objects might then be placed, so other empty
3529 subobjects might later overlap). */
3533 else
3537 }
3539 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3540 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3541 virtual bases of TYPE are examined. */
3543 static int
3545 tree offset,
3546 splay_tree offsets,
3548 {
3549 splay_tree_node max_node;
3551 /* Get the node in OFFSETS that indicates the maximum offset where
3552 an empty subobject is located. */
3554 /* If there aren't any empty subobjects, then there's no point in
3555 performing this check. */
3561 vbases_p);
3562 }
3564 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3565 non-static data member of the type indicated by RLI. BINFO is the
3566 binfo corresponding to the base subobject, OFFSETS maps offsets to
3567 types already located at those offsets. This function determines
3568 the position of the DECL. */
3570 static void
3572 tree decl,
3573 tree binfo,
3574 splay_tree offsets)
3575 {
3578 tree type;
3581 {
3582 /* For the purposes of determining layout conflicts, we want to
3583 use the class type of BINFO; TREE_TYPE (DECL) will be the
3584 CLASSTYPE_AS_BASE version, which does not contain entries for
3585 zero-sized bases. */
3588 }
3589 else
3590 {
3593 }
3595 /* Try to place the field. It may take more than one try if we have
3596 a hard time placing the field without putting two objects of the
3597 same type at the same address. */
3599 {
3602 /* Place this field. */
3606 /* We have to check to see whether or not there is already
3607 something of the same type at the offset we're about to use.
3608 For example, consider:
3610 struct S {};
3611 struct T : public S { int i; };
3612 struct U : public S, public T {};
3614 Here, we put S at offset zero in U. Then, we can't put T at
3615 offset zero -- its S component would be at the same address
3616 as the S we already allocated. So, we have to skip ahead.
3617 Since all data members, including those whose type is an
3618 empty class, have nonzero size, any overlap can happen only
3619 with a direct or indirect base-class -- it can't happen with
3620 a data member. */
3621 /* In a union, overlap is permitted; all members are placed at
3622 offset zero. */
3625 /* G++ 3.2 did not check for overlaps when placing a non-empty
3626 virtual base. */
3631 {
3632 /* Strip off the size allocated to this field. That puts us
3633 at the first place we could have put the field with
3634 proper alignment. */
3637 /* Bump up by the alignment required for the type. */
3638 rli->bitpos
3644 }
3645 else
3646 /* There was no conflict. We're done laying out this field. */
3648 }
3650 /* Now that we know where it will be placed, update its
3651 BINFO_OFFSET. */
3653 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3654 this point because their BINFO_OFFSET is copied from another
3655 hierarchy. Therefore, we may not need to add the entire
3656 OFFSET. */
3662 }
3664 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3666 static int
3668 tree offset,
3669 splay_tree offsets ATTRIBUTE_UNUSED)
3670 {
3672 }
3674 /* Layout the empty base BINFO. EOC indicates the byte currently just
3675 past the end of the class, and should be correctly aligned for a
3676 class of the type indicated by BINFO; OFFSETS gives the offsets of
3677 the empty bases allocated so far. T is the most derived
3678 type. Return nonzero iff we added it at the end. */
3680 static bool
3683 {
3684 tree alignment;
3688 /* This routine should only be used for empty classes. */
3693 {
3695 propagate_binfo_offsets
3698 else
3700 "offset of empty base %qT may not be ABI-compliant and may"
3703 }
3705 /* This is an empty base class. We first try to put it at offset
3706 zero. */
3709 offsets,
3711 {
3712 /* That didn't work. Now, we move forward from the next
3713 available spot in the class. */
3717 {
3720 offsets,
3722 /* We finally found a spot where there's no overlap. */
3725 /* There's overlap here, too. Bump along to the next spot. */
3727 }
3728 }
3731 {
3736 }
3739 }
3741 /* Layout the base given by BINFO in the class indicated by RLI.
3742 *BASE_ALIGN is a running maximum of the alignments of
3743 any base class. OFFSETS gives the location of empty base
3744 subobjects. T is the most derived type. Return nonzero if the new
3745 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3746 *NEXT_FIELD, unless BINFO is for an empty base class.
3748 Returns the location at which the next field should be inserted. */
3753 {
3758 /* This error is now reported in xref_tag, thus giving better
3759 location information. */
3762 /* Place the base class. */
3764 {
3765 tree decl;
3767 /* The containing class is non-empty because it has a non-empty
3768 base class. */
3771 /* Create the FIELD_DECL. */
3778 {
3786 /* Try to place the field. It may take more than one try if we
3787 have a hard time placing the field without putting two
3788 objects of the same type at the same address. */
3790 /* Add the new FIELD_DECL to the list of fields for T. */
3794 }
3795 }
3796 else
3797 {
3798 tree eoc;
3801 /* On some platforms (ARM), even empty classes will not be
3802 byte-aligned. */
3807 /* A nearly-empty class "has no proper base class that is empty,
3808 not morally virtual, and at an offset other than zero." */
3810 {
3813 /* The check above (used in G++ 3.2) is insufficient because
3814 an empty class placed at offset zero might itself have an
3815 empty base at a nonzero offset. */
3817 empty_base_at_nonzero_offset_p,
3818 size_zero_node,
3822 {
3825 else
3827 "class %qT will be considered nearly empty in a "
3829 }
3830 }
3832 /* We do not create a FIELD_DECL for empty base classes because
3833 it might overlap some other field. We want to be able to
3834 create CONSTRUCTORs for the class by iterating over the
3835 FIELD_DECLs, and the back end does not handle overlapping
3836 FIELD_DECLs. */
3838 /* An empty virtual base causes a class to be non-empty
3839 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3840 here because that was already done when the virtual table
3841 pointer was created. */
3842 }
3844 /* Record the offsets of BINFO and its base subobjects. */
3847 offsets,
3851 }
3853 /* Layout all of the non-virtual base classes. Record empty
3854 subobjects in OFFSETS. T is the most derived type. Return nonzero
3855 if the type cannot be nearly empty. The fields created
3856 corresponding to the base classes will be inserted at
3857 *NEXT_FIELD. */
3859 static void
3862 {
3863 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3864 subobjects. */
3869 /* The primary base class is always allocated first. */
3874 /* Now allocate the rest of the bases. */
3876 {
3877 tree base_binfo;
3881 /* The primary base was already allocated above, so we don't
3882 need to allocate it again here. */
3886 /* Virtual bases are added at the end (a primary virtual base
3887 will have already been added). */
3893 }
3894 }
3896 /* Go through the TYPE_METHODS of T issuing any appropriate
3897 diagnostics, figuring out which methods override which other
3898 methods, and so forth. */
3900 static void
3902 {
3903 tree x;
3906 {
3910 /* The name of the field is the original field name
3911 Save this in auxiliary field for later overloading. */
3913 {
3917 }
3918 /* All user-provided destructors are non-trivial.
3919 Constructors and assignment ops are handled in
3920 grok_special_member_properties. */
3923 }
3924 }
3926 /* FN is a constructor or destructor. Clone the declaration to create
3927 a specialized in-charge or not-in-charge version, as indicated by
3928 NAME. */
3930 static tree
3932 {
3933 tree parms;
3934 tree clone;
3936 /* Copy the function. */
3938 /* Reset the function name. */
3941 /* Remember where this function came from. */
3943 /* Make it easy to find the CLONE given the FN. */
3947 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3949 {
3956 }
3959 /* There's no pending inline data for this function. */
3963 /* The base-class destructor is not virtual. */
3965 {
3969 }
3971 /* If there was an in-charge parameter, drop it from the function
3972 type. */
3974 {
3975 tree basetype;
3976 tree parmtypes;
3977 tree exceptions;
3982 /* Skip the `this' parameter. */
3984 /* Skip the in-charge parameter. */
3986 /* And the VTT parm, in a complete [cd]tor. */
3990 /* If this is subobject constructor or destructor, add the vtt
3991 parameter. */
3995 parmtypes);
3998 exceptions);
4002 }
4004 /* Copy the function parameters. */
4006 /* Remove the in-charge parameter. */
4008 {
4012 }
4013 /* And the VTT parm, in a complete [cd]tor. */
4015 {
4018 else
4019 {
4023 }
4024 }
4027 {
4030 }
4032 /* Create the RTL for this function. */
4040 }
4042 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4043 not invoke this function directly.
4045 For a non-thunk function, returns the address of the slot for storing
4046 the function it is a clone of. Otherwise returns NULL_TREE.
4048 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4049 cloned_function is unset. This is to support the separate
4050 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4051 on a template makes sense, but not the former. */
4053 tree *
4055 {
4063 {
4064 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4067 else
4068 #endif
4070 }
4075 else
4077 }
4079 /* Produce declarations for all appropriate clones of FN. If
4080 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4081 CLASTYPE_METHOD_VEC as well. */
4083 void
4085 {
4086 tree clone;
4088 /* Avoid inappropriate cloning. */
4094 {
4095 /* For each constructor, we need two variants: an in-charge version
4096 and a not-in-charge version. */
4103 }
4104 else
4105 {
4108 /* For each destructor, we need three variants: an in-charge
4109 version, a not-in-charge version, and an in-charge deleting
4110 version. We clone the deleting version first because that
4111 means it will go second on the TYPE_METHODS list -- and that
4112 corresponds to the correct layout order in the virtual
4113 function table.
4115 For a non-virtual destructor, we do not build a deleting
4116 destructor. */
4118 {
4122 }
4129 }
4131 /* Note that this is an abstract function that is never emitted. */
4133 }
4135 /* DECL is an in charge constructor, which is being defined. This will
4136 have had an in class declaration, from whence clones were
4137 declared. An out-of-class definition can specify additional default
4138 arguments. As it is the clones that are involved in overload
4139 resolution, we must propagate the information from the DECL to its
4140 clones. */
4142 void
4144 {
4145 tree clone;
4149 {
4156 /* Skip the 'this' parameter. */
4172 {
4177 {
4178 /* A default parameter has been added. Adjust the
4179 clone's parameters. */
4183 tree type;
4188 {
4191 clone_parms);
4193 }
4196 clone_parms);
4205 }
4206 }
4208 }
4209 }
4211 /* For each of the constructors and destructors in T, create an
4212 in-charge and not-in-charge variant. */
4214 static void
4216 {
4217 tree fns;
4219 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4220 out now. */
4228 }
4230 /* Returns true iff class T has a user-defined constructor other than
4231 the default constructor. */
4233 bool
4235 {
4236 tree fns;
4242 {
4249 }
4252 }
4254 /* Returns the defaulted constructor if T has one. Otherwise, returns
4255 NULL_TREE. */
4257 tree
4259 {
4266 {
4270 {
4276 }
4277 }
4280 }
4282 /* Returns true iff FN is a user-provided function, i.e. user-declared
4283 and not defaulted at its first declaration; or explicit, private,
4284 protected, or non-const. */
4286 bool
4288 {
4291 else
4294 }
4296 /* Returns true iff class T has a user-provided constructor. */
4298 bool
4300 {
4301 tree fns;
4309 /* This can happen in error cases; avoid crashing. */
4318 }
4320 /* Returns true iff class T has a user-provided default constructor. */
4322 bool
4324 {
4325 tree fns;
4331 {
4337 }
4340 }
4342 /* Returns true iff class TYPE has a virtual destructor. */
4344 bool
4346 {
4347 tree dtor;
4355 }
4357 /* Returns true iff class T has a move constructor. */
4359 bool
4361 {
4362 tree fns;
4365 {
4368 }
4378 }
4380 /* Returns true iff class T has a move assignment operator. */
4382 bool
4384 {
4385 tree fns;
4388 {
4391 }
4399 }
4401 /* Remove all zero-width bit-fields from T. */
4403 static void
4405 {
4410 {
4413 /* We should not be confused by the fact that grokbitfield
4414 temporarily sets the width of the bit field into
4415 DECL_INITIAL (*fieldsp).
4416 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4417 to that width. */
4420 else
4422 }
4423 }
4425 /* Returns TRUE iff we need a cookie when dynamically allocating an
4426 array whose elements have the indicated class TYPE. */
4428 static bool
4430 {
4431 tree fns;
4436 /* If there's a non-trivial destructor, we need a cookie. In order
4437 to iterate through the array calling the destructor for each
4438 element, we'll have to know how many elements there are. */
4442 /* If the usual deallocation function is a two-argument whose second
4443 argument is of type `size_t', then we have to pass the size of
4444 the array to the deallocation function, so we will need to store
4445 a cookie. */
4449 /* If there are no `operator []' members, or the lookup is
4450 ambiguous, then we don't need a cookie. */
4453 /* Loop through all of the functions. */
4455 {
4456 tree fn;
4457 tree second_parm;
4459 /* Select the current function. */
4461 /* See if this function is a one-argument delete function. If
4462 it is, then it will be the usual deallocation function. */
4466 /* Do not consider this function if its second argument is an
4467 ellipsis. */
4470 /* Otherwise, if we have a two-argument function and the second
4471 argument is `size_t', it will be the usual deallocation
4472 function -- unless there is one-argument function, too. */
4476 }
4479 }
4481 /* Check the validity of the bases and members declared in T. Add any
4482 implicitly-generated functions (like copy-constructors and
4483 assignment operators). Compute various flag bits (like
4484 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4485 level: i.e., independently of the ABI in use. */
4487 static void
4489 {
4490 /* Nonzero if the implicitly generated copy constructor should take
4491 a non-const reference argument. */
4493 /* Nonzero if the implicitly generated assignment operator
4494 should take a non-const reference argument. */
4498 tree access_decls;
4501 tree fn;
4503 /* By default, we use const reference arguments and generate default
4504 constructors. */
4508 /* Check all the base-classes. */
4513 /* Check all the method declarations. */
4516 /* Save the initial values of these flags which only indicate whether
4517 or not the class has user-provided functions. As we analyze the
4518 bases and members we can set these flags for other reasons. */
4522 /* Check all the data member declarations. We cannot call
4523 check_field_decls until we have called check_bases check_methods,
4524 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4525 being set appropriately. */
4532 /* A nearly-empty class has to be vptr-containing; a nearly empty
4533 class contains just a vptr. */
4537 /* Do some bookkeeping that will guide the generation of implicitly
4538 declared member functions. */
4541 /* We need to call a constructor for this class if it has a
4542 user-provided constructor, or if the default constructor is going
4543 to initialize the vptr. (This is not an if-and-only-if;
4544 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4545 themselves need constructing.) */
4548 /* [dcl.init.aggr]
4550 An aggregate is an array or a class with no user-provided
4551 constructors ... and no virtual functions.
4553 Again, other conditions for being an aggregate are checked
4554 elsewhere. */
4557 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4558 retain the old definition internally for ABI reasons. */
4567 /* If the class has no user-declared constructor, but does have
4568 non-static const or reference data members that can never be
4569 initialized, issue a warning. */
4571 /* Classes with user-declared constructors are presumed to
4572 initialize these members. */
4574 /* Aggregates can be initialized with brace-enclosed
4575 initializers. */
4577 {
4578 tree field;
4581 {
4582 tree type;
4596 }
4597 }
4599 /* Synthesize any needed methods. */
4601 cant_have_const_ctor,
4602 no_const_asn_ref,
4603 cant_have_lazy_ctor,
4604 cant_have_lazy_opeq);
4606 /* Check defaulted declarations here so we have cant_have_const_ctor
4607 and don't need to worry about clones. */
4610 {
4613 {
4614 bool imp_const_p
4620 /* If the function is defaulted outside the class, we just
4621 give the synthesis error. */
4627 }
4629 }
4632 {
4633 /* "The closure type associated with a lambda-expression has a deleted
4634 default constructor and a deleted copy assignment operator." */
4640 /* "This class type is not an aggregate." */
4642 }
4644 /* Create the in-charge and not-in-charge variants of constructors
4645 and destructors. */
4648 /* Process the using-declarations. */
4652 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4655 /* Figure out whether or not we will need a cookie when dynamically
4656 allocating an array of this type. */
4659 }
4661 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4662 accordingly. If a new vfield was created (because T doesn't have a
4663 primary base class), then the newly created field is returned. It
4664 is not added to the TYPE_FIELDS list; it is the caller's
4665 responsibility to do that. Accumulate declared virtual functions
4666 on VIRTUALS_P. */
4668 static tree
4670 {
4671 tree fn;
4673 /* Collect the virtual functions declared in T. */
4677 {
4686 }
4688 /* If we couldn't find an appropriate base class, create a new field
4689 here. Even if there weren't any new virtual functions, we might need a
4690 new virtual function table if we're supposed to include vptrs in
4691 all classes that need them. */
4693 {
4694 /* We build this decl with vtbl_ptr_type_node, which is a
4695 `vtable_entry_type*'. It might seem more precise to use
4696 `vtable_entry_type (*)[N]' where N is the number of virtual
4697 functions. However, that would require the vtable pointer in
4698 base classes to have a different type than the vtable pointer
4699 in derived classes. We could make that happen, but that
4700 still wouldn't solve all the problems. In particular, the
4701 type-based alias analysis code would decide that assignments
4702 to the base class vtable pointer can't alias assignments to
4703 the derived class vtable pointer, since they have different
4704 types. Thus, in a derived class destructor, where the base
4705 class constructor was inlined, we could generate bad code for
4706 setting up the vtable pointer.
4708 Therefore, we use one type for all vtable pointers. We still
4709 use a type-correct type; it's just doesn't indicate the array
4710 bounds. That's better than using `void*' or some such; it's
4711 cleaner, and it let's the alias analysis code know that these
4712 stores cannot alias stores to void*! */
4713 tree field;
4726 /* This class is non-empty. */
4730 }
4733 }
4735 /* Add OFFSET to all base types of BINFO which is a base in the
4736 hierarchy dominated by T.
4738 OFFSET, which is a type offset, is number of bytes. */
4740 static void
4742 {
4744 tree primary_binfo;
4745 tree base_binfo;
4747 /* Update BINFO's offset. */
4752 offset));
4754 /* Find the primary base class. */
4760 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4761 downwards. */
4763 {
4764 /* Don't do the primary base twice. */
4772 }
4773 }
4775 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4776 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4777 empty subobjects of T. */
4779 static void
4781 {
4782 tree vbase;
4791 {
4792 /* In G++ 3.2, we incorrectly rounded the size before laying out
4793 the virtual bases. */
4795 #ifdef STRUCTURE_SIZE_BOUNDARY
4796 /* Packed structures don't need to have minimum size. */
4799 #endif
4803 }
4805 /* Find the last field. The artificial fields created for virtual
4806 bases will go after the last extant field to date. */
4811 /* Go through the virtual bases, allocating space for each virtual
4812 base that is not already a primary base class. These are
4813 allocated in inheritance graph order. */
4815 {
4820 {
4823 /* This virtual base is not a primary base of any class in the
4824 hierarchy, so we have to add space for it. */
4828 /* If the first virtual base might have been placed at a
4829 lower address, had we started from CLASSTYPE_SIZE, rather
4830 than TYPE_SIZE, issue a warning. There can be both false
4831 positives and false negatives from this warning in rare
4832 cases; to deal with all the possibilities would probably
4833 require performing both layout algorithms and comparing
4834 the results which is not particularly tractable. */
4836 && first_vbase
4837 && (tree_int_cst_lt
4842 bitsize_unit_node),
4845 "offset of virtual base %qT is not ABI-compliant and "
4847 basetype);
4850 }
4851 }
4852 }
4854 /* Returns the offset of the byte just past the end of the base class
4855 BINFO. */
4857 static tree
4859 {
4860 tree size;
4865 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4866 allocate some space for it. It cannot have virtual bases, so
4867 TYPE_SIZE_UNIT is fine. */
4869 else
4873 }
4875 /* Returns the offset of the byte just past the end of the base class
4876 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4877 only non-virtual bases are included. */
4879 static tree
4881 {
4884 tree binfo;
4885 tree base_binfo;
4886 tree offset;
4891 {
4901 }
4903 /* G++ 3.2 did not check indirect virtual bases. */
4907 {
4911 }
4914 }
4916 /* Warn about bases of T that are inaccessible because they are
4917 ambiguous. For example:
4919 struct S {};
4920 struct T : public S {};
4921 struct U : public S, public T {};
4923 Here, `(S*) new U' is not allowed because there are two `S'
4924 subobjects of U. */
4926 static void
4928 {
4931 tree basetype;
4932 tree binfo;
4933 tree base_binfo;
4935 /* If there are no repeated bases, nothing can be ambiguous. */
4939 /* Check direct bases. */
4942 {
4948 }
4950 /* Check for ambiguous virtual bases. */
4954 {
4960 }
4961 }
4963 /* Compare two INTEGER_CSTs K1 and K2. */
4965 static int
4967 {
4969 }
4971 /* Increase the size indicated in RLI to account for empty classes
4972 that are "off the end" of the class. */
4974 static void
4976 {
4977 tree eoc;
4978 tree rli_size;
4980 /* It might be the case that we grew the class to allocate a
4981 zero-sized base class. That won't be reflected in RLI, yet,
4982 because we are willing to overlay multiple bases at the same
4983 offset. However, now we need to make sure that RLI is big enough
4984 to reflect the entire class. */
4990 {
4992 /* In version 1 of the ABI, the size of a class that ends with
4993 a bitfield was not rounded up to a whole multiple of a
4994 byte. Because rli_size_unit_so_far returns only the number
4995 of fully allocated bytes, any extra bits were not included
4996 in the size. */
4998 else
4999 /* The size should have been rounded to a whole byte. */
5002 rli->bitpos
5011 }
5012 }
5014 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
5015 BINFO_OFFSETs for all of the base-classes. Position the vtable
5016 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
5018 static void
5020 {
5021 tree non_static_data_members;
5022 tree field;
5023 tree vptr;
5024 record_layout_info rli;
5025 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
5026 types that appear at that offset. */
5027 splay_tree empty_base_offsets;
5028 /* True if the last field layed out was a bit-field. */
5030 /* The location at which the next field should be inserted. */
5032 /* T, as a base class. */
5033 tree base_t;
5035 /* Keep track of the first non-static data member. */
5038 /* Start laying out the record. */
5041 /* Mark all the primary bases in the hierarchy. */
5044 /* Create a pointer to our virtual function table. */
5047 /* The vptr is always the first thing in the class. */
5049 {
5054 }
5055 else
5058 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5063 /* Layout the non-static data members. */
5065 {
5066 tree type;
5067 tree padding;
5069 /* We still pass things that aren't non-static data members to
5070 the back end, in case it wants to do something with them. */
5072 {
5074 /* If the static data member has incomplete type, keep track
5075 of it so that it can be completed later. (The handling
5076 of pending statics in finish_record_layout is
5077 insufficient; consider:
5079 struct S1;
5080 struct S2 { static S1 s1; };
5082 At this point, finish_record_layout will be called, but
5083 S1 is still incomplete.) */
5085 {
5087 /* The visibility of static data members is determined
5088 at their point of declaration, not their point of
5089 definition. */
5091 }
5093 }
5101 /* If this field is a bit-field whose width is greater than its
5102 type, then there are some special rules for allocating
5103 it. */
5106 {
5108 tree integer_type;
5110 /* We must allocate the bits as if suitably aligned for the
5111 longest integer type that fits in this many bits. type
5112 of the field. Then, we are supposed to use the left over
5113 bits as additional padding. */
5122 /* ITK now indicates a type that is too large for the
5123 field. We have to back up by one to find the largest
5124 type that fits. */
5125 do
5126 {
5131 /* Figure out how much additional padding is required. GCC
5132 3.2 always created a padding field, even if it had zero
5133 width. */
5136 {
5138 /* In a union, the padding field must have the full width
5139 of the bit-field; all fields start at offset zero. */
5141 else
5142 {
5145 "ABI-compliant and may change in a future "
5147 t);
5150 }
5151 }
5152 #ifdef PCC_BITFIELD_TYPE_MATTERS
5153 /* An unnamed bitfield does not normally affect the
5154 alignment of the containing class on a target where
5155 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5156 make any exceptions for unnamed bitfields when the
5157 bitfields are longer than their types. Therefore, we
5158 temporarily give the field a name. */
5160 {
5163 }
5164 #endif
5169 empty_base_offsets);
5172 /* Now that layout has been performed, set the size of the
5173 field to the size of its declared type; the rest of the
5174 field is effectively invisible. */
5176 /* We must also reset the DECL_MODE of the field. */
5181 /* Versions of G++ before G++ 3.4 did not reset the
5182 DECL_MODE. */
5184 "the offset of %qD may not be ABI-compliant and may "
5186 }
5187 else
5189 empty_base_offsets);
5191 /* Remember the location of any empty classes in FIELD. */
5195 empty_base_offsets,
5198 /* If a bit-field does not immediately follow another bit-field,
5199 and yet it starts in the middle of a byte, we have failed to
5200 comply with the ABI. */
5203 /* The TREE_NO_WARNING flag gets set by Objective-C when
5204 laying out an Objective-C class. The ObjC ABI differs
5205 from the C++ ABI, and so we do not want a warning
5206 here. */
5208 && !last_field_was_bitfield
5211 bitsize_unit_node)))
5215 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5216 offset of the field. */
5223 "classes to be placed at different locations in a "
5226 /* The middle end uses the type of expressions to determine the
5227 possible range of expression values. In order to optimize
5228 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5229 must be made aware of the width of "i", via its type.
5231 Because C++ does not have integer types of arbitrary width,
5232 we must (for the purposes of the front end) convert from the
5233 type assigned here to the declared type of the bitfield
5234 whenever a bitfield expression is used as an rvalue.
5235 Similarly, when assigning a value to a bitfield, the value
5236 must be converted to the type given the bitfield here. */
5238 {
5243 {
5250 }
5251 }
5253 /* If we needed additional padding after this field, add it
5254 now. */
5256 {
5257 tree padding_field;
5260 FIELD_DECL,
5261 NULL_TREE,
5262 char_type_node);
5269 NULL_TREE,
5270 empty_base_offsets);
5271 }
5274 }
5277 {
5278 /* Make sure that we are on a byte boundary so that the size of
5279 the class without virtual bases will always be a round number
5280 of bytes. */
5283 }
5285 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5286 padding. */
5290 /* Delete all zero-width bit-fields from the list of fields. Now
5291 that the type is laid out they are no longer important. */
5294 /* Create the version of T used for virtual bases. We do not use
5295 make_class_type for this version; this is an artificial type. For
5296 a POD type, we just reuse T. */
5298 {
5301 /* Set the size and alignment for the new type. In G++ 3.2, all
5302 empty classes were considered to have size zero when used as
5303 base classes. */
5305 {
5310 "layout of classes derived from empty class %qT "
5312 t);
5313 }
5314 else
5315 {
5316 tree eoc;
5318 /* If the ABI version is not at least two, and the last
5319 field was a bit-field, RLI may not be on a byte
5320 boundary. In particular, rli_size_unit_so_far might
5321 indicate the last complete byte, while rli_size_so_far
5322 indicates the total number of bits used. Therefore,
5323 rli_size_so_far, rather than rli_size_unit_so_far, is
5324 used to compute TYPE_SIZE_UNIT. */
5332 eoc);
5339 }
5343 /* Copy the fields from T. */
5347 {
5349 FIELD_DECL,
5359 }
5361 /* Record the base version of the type. */
5364 }
5365 else
5368 /* Every empty class contains an empty class. */
5372 /* Set the TYPE_DECL for this type to contain the right
5373 value for DECL_OFFSET, so that we can use it as part
5374 of a COMPONENT_REF for multiple inheritance. */
5377 /* Now fix up any virtual base class types that we left lying
5378 around. We must get these done before we try to lay out the
5379 virtual function table. As a side-effect, this will remove the
5380 base subobject fields. */
5383 /* Make sure that empty classes are reflected in RLI at this
5384 point. */
5387 /* Make sure not to create any structures with zero size. */
5393 /* If this is a non-POD, declaring it packed makes a difference to how it
5394 can be used as a field; don't let finalize_record_size undo it. */
5398 /* Let the back end lay out the type. */
5401 /* Warn about bases that can't be talked about due to ambiguity. */
5404 /* Now that we're done with layout, give the base fields the real types. */
5409 /* Clean up. */
5416 }
5418 /* Determine the "key method" for the class type indicated by TYPE,
5419 and set CLASSTYPE_KEY_METHOD accordingly. */
5421 void
5423 {
5424 tree method;
5427 || processing_template_decl
5432 /* The key method is the first non-pure virtual function that is not
5433 inline at the point of class definition. On some targets the
5434 key function may not be inline; those targets should not call
5435 this function until the end of the translation unit. */
5441 {
5444 }
5447 }
5449 /* Perform processing required when the definition of T (a class type)
5450 is complete. */
5452 void
5454 {
5455 tree x;
5456 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5461 {
5466 }
5468 /* If this type was previously laid out as a forward reference,
5469 make sure we lay it out again. */
5473 /* Make assumptions about the class; we'll reset the flags if
5474 necessary. */
5479 /* Do end-of-class semantic processing: checking the validity of the
5480 bases and members and add implicitly generated methods. */
5483 /* Find the key method. */
5485 {
5486 /* The Itanium C++ ABI permits the key method to be chosen when
5487 the class is defined -- even though the key method so
5488 selected may later turn out to be an inline function. On
5489 some systems (such as ARM Symbian OS) the key method cannot
5490 be determined until the end of the translation unit. On such
5491 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5492 will cause the class to be added to KEYED_CLASSES. Then, in
5493 finish_file we will determine the key method. */
5497 /* If a polymorphic class has no key method, we may emit the vtable
5498 in every translation unit where the class definition appears. */
5501 }
5503 /* Layout the class itself. */
5506 /* We use the base type for trivial assignments, and hence it
5507 needs a mode. */
5512 /* If necessary, create the primary vtable for this class. */
5514 {
5515 /* We must enter these virtuals into the table. */
5519 /* Here we know enough to change the type of our virtual
5520 function table, but we will wait until later this function. */
5522 }
5525 {
5527 tree fn;
5534 /* Add entries for virtual functions introduced by this class. */
5538 /* Set DECL_VINDEX for all functions declared in this class. */
5540 fn;
5542 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5544 {
5548 /* A thunk. We should never be calling this entry directly
5549 from this vtable -- we'd use the entry for the non
5550 thunk base function. */
5554 }
5555 }
5559 /* Complete the rtl for any static member objects of the type we're
5560 working on. */
5567 /* Done with FIELDS...now decide whether to sort these for
5568 faster lookups later.
5570 We use a small number because most searches fail (succeeding
5571 ultimately as the search bores through the inheritance
5572 hierarchy), and we want this failure to occur quickly. */
5576 {
5582 field_decl_cmp);
5584 }
5586 /* Complain if one of the field types requires lower visibility. */
5589 /* Make the rtl for any new vtables we have created, and unmark
5590 the base types we marked. */
5593 /* Build the VTT for T. */
5596 /* This warning does not make sense for Java classes, since they
5597 cannot have destructors. */
5599 {
5600 tree dtor;
5604 if it were virtual, we would have created it by now. */
5605 !dtor
5614 "%q#T has virtual functions and accessible"
5616 }
5623 /* Class layout, assignment of virtual table slots, etc., is now
5624 complete. Give the back end a chance to tweak the visibility of
5625 the class or perform any other required target modifications. */
5632 /* Finish debugging output for this type. */
5634 }
5636 /* When T was built up, the member declarations were added in reverse
5637 order. Rearrange them to declaration order. */
5639 void
5641 {
5642 tree next;
5643 tree prev;
5644 tree x;
5646 /* The following lists are all in reverse order. Put them in
5647 declaration order now. */
5651 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5652 reverse order, so we can't just use nreverse. */
5657 {
5661 }
5663 {
5667 }
5668 }
5670 tree
5672 {
5675 /* Now that we've got all the field declarations, reverse everything
5676 as necessary. */
5681 /* Nadger the current location so that diagnostics point to the start of
5682 the struct, not the end. */
5686 {
5687 tree x;
5693 /* We need to emit an error message if this type was used as a parameter
5694 and it is an abstract type, even if it is a template. We construct
5695 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5696 account and we call complete_vars with this type, which will check
5697 the PARM_DECLS. Note that while the type is being defined,
5698 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5699 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5706 /* Remember current #pragma pack value. */
5708 }
5709 else
5718 else
5725 }
5726 \f
5727 /* Return the dynamic type of INSTANCE, if known.
5728 Used to determine whether the virtual function table is needed
5729 or not.
5731 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5732 of our knowledge of its type. *NONNULL should be initialized
5733 before this function is called. */
5735 static tree
5737 {
5738 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5741 {
5745 else
5749 /* This is a call to a constructor, hence it's never zero. */
5751 {
5755 }
5759 /* This is a call to a constructor, hence it's never zero. */
5761 {
5765 }
5774 /* Propagate nonnull. */
5779 CASE_CONVERT:
5785 {
5786 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5787 with a real object -- given &p->f, p can still be null. */
5789 /* ??? Probably should check DECL_WEAK here. */
5792 }
5796 /* If this component is really a base class reference, then the field
5797 itself isn't definitive. */
5806 {
5810 }
5811 /* fall through... */
5816 {
5820 }
5822 {
5826 /* if we're in a ctor or dtor, we know our type. */
5830 {
5834 }
5835 }
5837 {
5838 /* We only need one hash table because it is always left empty. */
5842 htab_hash_pointer,
5843 htab_eq_pointer,
5846 /* Reference variables should be references to objects. */
5850 /* Enter the INSTANCE in a table to prevent recursion; a
5851 variable's initializer may refer to the variable
5852 itself. */
5856 {
5857 tree type;
5866 }
5867 }
5872 }
5873 #undef RECUR
5874 }
5876 /* Return nonzero if the dynamic type of INSTANCE is known, and
5877 equivalent to the static type. We also handle the case where
5878 INSTANCE is really a pointer. Return negative if this is a
5879 ctor/dtor. There the dynamic type is known, but this might not be
5880 the most derived base of the original object, and hence virtual
5881 bases may not be layed out according to this type.
5883 Used to determine whether the virtual function table is needed
5884 or not.
5886 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5887 of our knowledge of its type. *NONNULL should be initialized
5888 before this function is called. */
5890 int
5892 {
5903 }
5905 \f
5906 void
5908 {
5911 current_class_stack
5919 }
5921 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5923 static void
5925 {
5926 tree type;
5928 /* We are re-entering the same class we just left, so we don't
5929 have to search the whole inheritance matrix to find all the
5930 decls to bind again. Instead, we install the cached
5931 class_shadowed list and walk through it binding names. */
5934 /* Restore IDENTIFIER_TYPE_VALUE. */
5936 type;
5939 }
5941 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5942 appropriate for TYPE.
5944 So that we may avoid calls to lookup_name, we cache the _TYPE
5945 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5947 For multiple inheritance, we perform a two-pass depth-first search
5948 of the type lattice. */
5950 void
5952 {
5953 class_stack_node_t csn;
5957 /* Make sure there is enough room for the new entry on the stack. */
5959 {
5961 current_class_stack
5963 current_class_stack_size);
5964 }
5966 /* Insert a new entry on the class stack. */
5973 current_class_depth++;
5975 /* Now set up the new type. */
5981 /* By default, things in classes are private, while things in
5982 structures or unions are public. */
5984 ? access_private_node
5990 {
5991 /* Forcibly remove any old class remnants. */
5993 }
5999 else
6001 }
6003 /* When we exit a toplevel class scope, we save its binding level so
6004 that we can restore it quickly. Here, we've entered some other
6005 class, so we must invalidate our cache. */
6007 void
6009 {
6011 }
6013 /* Get out of the current class scope. If we were in a class scope
6014 previously, that is the one popped to. */
6016 void
6018 {
6021 current_class_depth--;
6027 }
6029 /* Mark the top of the class stack as hidden. */
6031 void
6033 {
6036 }
6038 /* Mark the top of the class stack as un-hidden. */
6040 void
6042 {
6045 }
6047 /* Returns 1 if the class type currently being defined is either T or
6048 a nested type of T. */
6050 bool
6052 {
6060 /* We start looking from 1 because entry 0 is from global scope,
6061 and has no type. */
6063 {
6064 tree c;
6067 else
6068 {
6072 }
6077 }
6079 }
6081 /* If either current_class_type or one of its enclosing classes are derived
6082 from T, return the appropriate type. Used to determine how we found
6083 something via unqualified lookup. */
6085 tree
6087 {
6090 /* The bases of a dependent type are unknown. */
6101 {
6106 }
6109 }
6111 /* Returns the innermost class type which is not a lambda closure type. */
6113 tree
6115 {
6118 /* We start looking from 1 because entry 0 is from global scope,
6119 and has no type. */
6121 {
6122 tree c;
6125 else
6126 {
6130 }
6135 }
6137 }
6139 /* When entering a class scope, all enclosing class scopes' names with
6140 static meaning (static variables, static functions, types and
6141 enumerators) have to be visible. This recursive function calls
6142 pushclass for all enclosing class contexts until global or a local
6143 scope is reached. TYPE is the enclosed class. */
6145 void
6147 {
6148 /* A namespace might be passed in error cases, like A::B:C. */
6156 }
6158 /* Undoes a push_nested_class call. */
6160 void
6162 {
6168 }
6170 /* Returns the number of extern "LANG" blocks we are nested within. */
6172 int
6174 {
6176 }
6178 /* Set global variables CURRENT_LANG_NAME to appropriate value
6179 so that behavior of name-mangling machinery is correct. */
6181 void
6183 {
6187 {
6189 }
6191 {
6193 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6194 (See record_builtin_java_type in decl.c.) However, that causes
6195 incorrect debug entries if these types are actually used.
6196 So we re-enable debug output after extern "Java". */
6205 }
6207 {
6209 }
6210 else
6212 }
6214 /* Get out of the current language scope. */
6216 void
6218 {
6220 }
6221 \f
6222 /* Type instantiation routines. */
6224 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6225 matches the TARGET_TYPE. If there is no satisfactory match, return
6226 error_mark_node, and issue an error & warning messages under
6227 control of FLAGS. Permit pointers to member function if FLAGS
6228 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6229 a template-id, and EXPLICIT_TARGS are the explicitly provided
6230 template arguments.
6232 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6233 is the base path used to reference those member functions. If
6234 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6235 resolved to a member function, access checks will be performed and
6236 errors issued if appropriate. */
6238 static tree
6240 tree overload,
6241 tsubst_flags_t flags,
6243 tree explicit_targs,
6244 tree access_path)
6245 {
6246 /* Here's what the standard says:
6248 [over.over]
6250 If the name is a function template, template argument deduction
6251 is done, and if the argument deduction succeeds, the deduced
6252 arguments are used to generate a single template function, which
6253 is added to the set of overloaded functions considered.
6255 Non-member functions and static member functions match targets of
6256 type "pointer-to-function" or "reference-to-function." Nonstatic
6257 member functions match targets of type "pointer-to-member
6258 function;" the function type of the pointer to member is used to
6259 select the member function from the set of overloaded member
6260 functions. If a nonstatic member function is selected, the
6261 reference to the overloaded function name is required to have the
6262 form of a pointer to member as described in 5.3.1.
6264 If more than one function is selected, any template functions in
6265 the set are eliminated if the set also contains a non-template
6266 function, and any given template function is eliminated if the
6267 set contains a second template function that is more specialized
6268 than the first according to the partial ordering rules 14.5.5.2.
6269 After such eliminations, if any, there shall remain exactly one
6270 selected function. */
6273 /* We store the matches in a TREE_LIST rooted here. The functions
6274 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6275 interoperability with most_specialized_instantiation. */
6277 tree fn;
6278 tree target_fn_type;
6280 /* By the time we get here, we should be seeing only real
6281 pointer-to-member types, not the internal POINTER_TYPE to
6282 METHOD_TYPE representation. */
6288 /* Check that the TARGET_TYPE is reasonable. */
6292 /* This is OK, too. */
6295 /* This is OK, too. This comes from a conversion to reference
6296 type. */
6298 else
6299 {
6305 }
6307 /* Non-member functions and static member functions match targets of type
6308 "pointer-to-function" or "reference-to-function." Nonstatic member
6309 functions match targets of type "pointer-to-member-function;" the
6310 function type of the pointer to member is used to select the member
6311 function from the set of overloaded member functions.
6313 So figure out the FUNCTION_TYPE that we want to match against. */
6316 /* If we can find a non-template function that matches, we can just
6317 use it. There's no point in generating template instantiations
6318 if we're just going to throw them out anyhow. But, of course, we
6319 can only do this when we don't *need* a template function. */
6321 {
6322 tree fns;
6325 {
6329 /* We're not looking for templates just yet. */
6334 /* We're looking for a non-static member, and this isn't
6335 one, or vice versa. */
6338 /* Ignore functions which haven't been explicitly
6339 declared. */
6343 /* See if there's a match. */
6346 }
6347 }
6349 /* Now, if we've already got a match (or matches), there's no need
6350 to proceed to the template functions. But, if we don't have a
6351 match we need to look at them, too. */
6353 {
6354 tree target_arg_types;
6355 tree target_ret_type;
6356 tree fns;
6359 tree arg;
6373 {
6375 tree instantiation;
6376 tree targs;
6379 /* We're only looking for templates. */
6384 /* We're not looking for a non-static member, and this is
6385 one, or vice versa. */
6388 /* Try to do argument deduction. */
6392 LOOKUP_NORMAL))
6393 /* Argument deduction failed. */
6396 /* Instantiate the template. */
6399 /* Instantiation failed. */
6402 /* See if there's a match. */
6405 }
6407 /* Now, remove all but the most specialized of the matches. */
6409 {
6414 NULL_TREE,
6415 NULL_TREE);
6416 }
6417 }
6419 /* Now we should have exactly one function in MATCHES. */
6421 {
6422 /* There were *no* matches. */
6424 {
6427 target_type);
6429 /* print_candidates expects a chain with the functions in
6430 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6431 so why be clever?). */
6434 matches);
6437 }
6439 }
6441 {
6442 /* There were too many matches. First check if they're all
6443 the same function. */
6444 tree match;
6452 {
6454 {
6457 target_type);
6459 /* Since print_candidates expects the functions in the
6460 TREE_VALUE slot, we flip them here. */
6465 }
6468 }
6469 }
6471 /* Good, exactly one match. Now, convert it to the correct type. */
6476 {
6484 {
6487 }
6488 }
6490 /* If we're doing overload resolution purely for the purpose of
6491 determining conversion sequences, we should not consider the
6492 function used. If this conversion sequence is selected, the
6493 function will be marked as used at this point. */
6495 {
6496 /* Make =delete work with SFINAE. */
6501 }
6503 /* We could not check access to member functions when this
6504 expression was originally created since we did not know at that
6505 time to which function the expression referred. */
6508 {
6511 }
6515 else
6516 {
6517 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6518 will mark the function as addressed, but here we must do it
6519 explicitly. */
6523 }
6524 }
6526 /* This function will instantiate the type of the expression given in
6527 RHS to match the type of LHSTYPE. If errors exist, then return
6528 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6529 we complain on errors. If we are not complaining, never modify rhs,
6530 as overload resolution wants to try many possible instantiations, in
6531 the hope that at least one will work.
6533 For non-recursive calls, LHSTYPE should be a function, pointer to
6534 function, or a pointer to member function. */
6536 tree
6538 {
6545 {
6549 }
6552 {
6558 /* Microsoft allows `A::f' to be resolved to a
6559 pointer-to-member. */
6560 ;
6561 else
6562 {
6567 }
6568 }
6571 {
6574 }
6576 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6577 deduce any type information. */
6579 {
6583 }
6585 /* There only a few kinds of expressions that may have a type
6586 dependent on overload resolution. */
6592 /* This should really only be used when attempting to distinguish
6593 what sort of a pointer to function we have. For now, any
6594 arithmetic operation which is not supported on pointers
6595 is rejected as an error. */
6598 {
6600 {
6606 /* Do not lose object's side effects. */
6610 }
6617 /* This can happen if we are forming a pointer-to-member for a
6618 member template. */
6621 /* Fall through. */
6624 {
6628 return
6632 }
6636 return
6640 access_path);
6643 {
6648 }
6655 }
6657 }
6658 \f
6659 /* Return the name of the virtual function pointer field
6660 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6661 this may have to look back through base types to find the
6662 ultimate field name. (For single inheritance, these could
6663 all be the same name. Who knows for multiple inheritance). */
6665 static tree
6667 {
6674 {
6680 }
6688 }
6690 void
6692 {
6693 #ifdef GATHER_STATISTICS
6697 {
6702 }
6703 #endif
6704 }
6706 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6707 according to [class]:
6708 The class-name is also inserted
6709 into the scope of the class itself. For purposes of access checking,
6710 the inserted class name is treated as if it were a public member name. */
6712 void
6714 {
6717 tree saved_cas;
6732 }
6734 /* Returns 1 if TYPE contains only padding bytes. */
6736 int
6738 {
6745 /* In G++ 3.2, whether or not a class was empty was determined by
6746 looking at its size. */
6749 else
6751 }
6753 /* Returns true if TYPE contains an empty class. */
6755 static bool
6757 {
6761 {
6762 tree field;
6763 tree binfo;
6764 tree base_binfo;
6776 }
6780 }
6782 /* Returns true if TYPE contains no actual data, just various
6783 possible combinations of empty classes. */
6785 bool
6787 {
6791 {
6792 tree field;
6793 tree binfo;
6794 tree base_binfo;
6807 }
6811 }
6813 /* Note that NAME was looked up while the current class was being
6814 defined and that the result of that lookup was DECL. */
6816 void
6818 {
6819 splay_tree names_used;
6821 /* If we're not defining a class, there's nothing to do. */
6827 /* If there's already a binding for this NAME, then we don't have
6828 anything to worry about. */
6841 }
6843 /* Note that NAME was declared (as DECL) in the current class. Check
6844 to see that the declaration is valid. */
6846 void
6848 {
6849 splay_tree names_used;
6850 splay_tree_node n;
6852 /* Look to see if we ever used this name. */
6853 names_used
6860 {
6861 /* [basic.scope.class]
6863 A name N used in a class S shall refer to the same declaration
6864 in its context and when re-evaluated in the completed scope of
6865 S. */
6869 }
6870 }
6872 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6873 Secondary vtables are merged with primary vtables; this function
6874 will return the VAR_DECL for the primary vtable. */
6876 tree
6878 {
6879 tree decl;
6883 {
6886 }
6890 }
6893 /* Returns the binfo for the primary base of BINFO. If the resulting
6894 BINFO is a virtual base, and it is inherited elsewhere in the
6895 hierarchy, then the returned binfo might not be the primary base of
6896 BINFO in the complete object. Check BINFO_PRIMARY_P or
6897 BINFO_LOST_PRIMARY_P to be sure. */
6899 static tree
6901 {
6902 tree primary_base;
6909 }
6911 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6913 static int
6915 {
6919 }
6921 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6922 INDENT should be zero when called from the top level; it is
6923 incremented recursively. IGO indicates the next expected BINFO in
6924 inheritance graph ordering. */
6926 static tree
6929 tree binfo,
6930 tree igo,
6932 {
6934 tree base_binfo;
6942 {
6945 }
6960 {
6964 TFF_PLAIN_IDENTIFIER),
6966 }
6968 {
6971 }
6976 {
6980 {
6984 TFF_PLAIN_IDENTIFIER));
6985 }
6987 {
6991 TFF_PLAIN_IDENTIFIER));
6992 }
6994 {
6998 TFF_PLAIN_IDENTIFIER));
6999 }
7001 {
7005 TFF_PLAIN_IDENTIFIER));
7006 }
7010 }
7016 }
7018 /* Dump the BINFO hierarchy for T. */
7020 static void
7022 {
7034 }
7036 /* Debug interface to hierarchy dumping. */
7038 void
7040 {
7042 }
7044 static void
7046 {
7051 {
7054 }
7055 }
7057 static void
7059 {
7060 tree value;
7062 HOST_WIDE_INT elt;
7070 TFF_PLAIN_IDENTIFIER));
7077 }
7079 static void
7081 {
7089 {
7096 {
7100 }
7104 }
7107 }
7109 static void
7111 {
7119 {
7124 }
7127 }
7129 /* Dump a function or thunk and its thunkees. */
7131 static void
7133 {
7136 tree thunks;
7144 {
7154 else
7160 }
7164 }
7166 /* Dump the thunks for FN. */
7168 void
7170 {
7172 }
7174 /* Virtual function table initialization. */
7176 /* Create all the necessary vtables for T and its base classes. */
7178 static void
7180 {
7181 tree vbase;
7185 /* We lay out the primary and secondary vtables in one contiguous
7186 vtable. The primary vtable is first, followed by the non-virtual
7187 secondary vtables in inheritance graph order. */
7191 /* Then come the virtual bases, also in inheritance graph order. */
7193 {
7197 }
7201 }
7203 /* Initialize the vtable for BINFO with the INITS. */
7205 static void
7207 {
7208 tree decl;
7214 }
7216 /* Build the VTT (virtual table table) for T.
7217 A class requires a VTT if it has virtual bases.
7219 This holds
7220 1 - primary virtual pointer for complete object T
7221 2 - secondary VTTs for each direct non-virtual base of T which requires a
7222 VTT
7223 3 - secondary virtual pointers for each direct or indirect base of T which
7224 has virtual bases or is reachable via a virtual path from T.
7225 4 - secondary VTTs for each direct or indirect virtual base of T.
7227 Secondary VTTs look like complete object VTTs without part 4. */
7229 static void
7231 {
7232 tree type;
7233 tree vtt;
7234 tree index;
7237 /* Build up the initializers for the VTT. */
7242 /* If we didn't need a VTT, we're done. */
7246 /* Figure out the type of the VTT. */
7250 /* Now, build the VTT object itself. */
7253 /* Add the VTT to the vtables list. */
7258 }
7260 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7261 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7262 and CHAIN the vtable pointer for this binfo after construction is
7263 complete. VALUE can also be another BINFO, in which case we recurse. */
7265 static tree
7267 {
7268 tree vt;
7271 {
7277 else
7279 }
7282 }
7284 /* Data for secondary VTT initialization. */
7286 {
7287 /* Is this the primary VTT? */
7290 /* Current index into the VTT. */
7291 tree index;
7293 /* Vector of initializers built up. */
7296 /* The type being constructed by this secondary VTT. */
7297 tree type_being_constructed;
7300 /* Recursively build the VTT-initializer for BINFO (which is in the
7301 hierarchy dominated by T). INITS points to the end of the initializer
7302 list to date. INDEX is the VTT index where the next element will be
7303 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7304 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7305 for virtual bases of T. When it is not so, we build the constructor
7306 vtables for the BINFO-in-T variant. */
7308 static void
7310 {
7312 tree b;
7313 tree init;
7314 secondary_vptr_vtt_init_data data;
7317 /* We only need VTTs for subobjects with virtual bases. */
7321 /* We need to use a construction vtable if this is not the primary
7322 VTT. */
7324 {
7327 /* Record the offset in the VTT where this sub-VTT can be found. */
7329 }
7331 /* Add the address of the primary vtable for the complete object. */
7335 {
7338 }
7341 /* Recursively add the secondary VTTs for non-virtual bases. */
7346 /* Add secondary virtual pointers for all subobjects of BINFO with
7347 either virtual bases or reachable along a virtual path, except
7348 subobjects that are non-virtual primary bases. */
7358 /* data.inits might have grown as we added secondary virtual pointers.
7359 Make sure our caller knows about the new vector. */
7363 /* Add the secondary VTTs for virtual bases in inheritance graph
7364 order. */
7366 {
7371 }
7372 else
7373 /* Remove the ctor vtables we created. */
7375 }
7377 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7378 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7380 static tree
7382 {
7385 /* We don't care about bases that don't have vtables. */
7389 /* We're only interested in proper subobjects of the type being
7390 constructed. */
7394 /* We're only interested in bases with virtual bases or reachable
7395 via a virtual path from the type being constructed. */
7400 /* We're not interested in non-virtual primary bases. */
7404 /* Record the index where this secondary vptr can be found. */
7406 {
7411 {
7412 /* It's a primary virtual base, and this is not a
7413 construction vtable. Find the base this is primary of in
7414 the inheritance graph, and use that base's vtable
7415 now. */
7418 }
7419 }
7421 /* Add the initializer for the secondary vptr itself. */
7424 /* Advance the vtt index. */
7429 }
7431 /* Called from build_vtt_inits via dfs_walk. After building
7432 constructor vtables and generating the sub-vtt from them, we need
7433 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7434 binfo of the base whose sub vtt was generated. */
7436 static tree
7438 {
7442 /* If this class has no vtable, none of its bases do. */
7446 /* This might be a primary base, so have no vtable in this
7447 hierarchy. */
7450 /* If we scribbled the construction vtable vptr into BINFO, clear it
7451 out now. */
7457 }
7459 /* Build the construction vtable group for BINFO which is in the
7460 hierarchy dominated by T. */
7462 static void
7464 {
7465 tree type;
7466 tree vtbl;
7467 tree id;
7468 tree vbase;
7471 /* See if we've already created this construction vtable group. */
7477 /* Build a version of VTBL (with the wrong type) for use in
7478 constructing the addresses of secondary vtables in the
7479 construction vtable group. */
7487 /* Add the vtables for each of our virtual bases using the vbase in T
7488 binfo. */
7490 vbase;
7492 {
7493 tree b;
7500 }
7502 /* Figure out the type of the construction vtable. */
7510 /* Initialize the construction vtable. */
7514 }
7516 /* Add the vtbl initializers for BINFO (and its bases other than
7517 non-virtual primaries) to the list of INITS. BINFO is in the
7518 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7519 the constructor the vtbl inits should be accumulated for. (If this
7520 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7521 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7522 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7523 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7524 but are not necessarily the same in terms of layout. */
7526 static void
7528 tree orig_binfo,
7529 tree rtti_binfo,
7530 tree vtbl,
7531 tree t,
7533 {
7535 tree base_binfo;
7540 /* If it doesn't have a vptr, we don't do anything. */
7544 /* If we're building a construction vtable, we're not interested in
7545 subobjects that don't require construction vtables. */
7551 /* Build the initializers for the BINFO-in-T vtable. */
7554 /* Walk the BINFO and its bases. We walk in preorder so that as we
7555 initialize each vtable we can figure out at what offset the
7556 secondary vtable lies from the primary vtable. We can't use
7557 dfs_walk here because we need to iterate through bases of BINFO
7558 and RTTI_BINFO simultaneously. */
7560 {
7561 /* Skip virtual bases. */
7567 inits);
7568 }
7569 }
7571 /* Called from accumulate_vtbl_inits. Adds the initializers for the
7572 BINFO vtable to L. */
7574 static void
7576 tree orig_binfo,
7577 tree rtti_binfo,
7578 tree orig_vtbl,
7579 tree t,
7581 {
7588 {
7589 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7590 primary virtual base. If it is not the same primary in
7591 the hierarchy of T, we'll need to generate a ctor vtable
7592 for it, to place at its location in T. If it is the same
7593 primary, we still need a VTT entry for the vtable, but it
7594 should point to the ctor vtable for the base it is a
7595 primary for within the sub-hierarchy of RTTI_BINFO.
7597 There are three possible cases:
7599 1) We are in the same place.
7600 2) We are a primary base within a lost primary virtual base of
7601 RTTI_BINFO.
7602 3) We are primary to something not a base of RTTI_BINFO. */
7604 tree b;
7607 /* First, look through the bases we are primary to for RTTI_BINFO
7608 or a virtual base. */
7611 {
7616 }
7617 /* If we run out of primary links, keep looking down our
7618 inheritance chain; we might be an indirect primary. */
7622 found:
7624 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7625 base B and it is a base of RTTI_BINFO, this is case 2. In
7626 either case, we share our vtable with LAST, i.e. the
7627 derived-most base within B of which we are a primary. */
7630 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7631 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7632 binfo_ctor_vtable after everything's been set up. */
7635 /* Otherwise, this is case 3 and we get our own. */
7636 }
7643 {
7644 tree index;
7647 /* Add the initializer for this vtable. */
7651 /* Figure out the position to which the VPTR should point. */
7658 index);
7660 }
7663 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7664 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7665 straighten this out. */
7668 /* Throw away any unneeded intializers. */
7670 else
7671 /* For an ordinary vtable, set BINFO_VTABLE. */
7673 }
7677 /* Construct the initializer for BINFO's virtual function table. BINFO
7678 is part of the hierarchy dominated by T. If we're building a
7679 construction vtable, the ORIG_BINFO is the binfo we should use to
7680 find the actual function pointers to put in the vtable - but they
7681 can be overridden on the path to most-derived in the graph that
7682 ORIG_BINFO belongs. Otherwise,
7683 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7684 BINFO that should be indicated by the RTTI information in the
7685 vtable; it will be a base class of T, rather than T itself, if we
7686 are building a construction vtable.
7688 The value returned is a TREE_LIST suitable for wrapping in a
7689 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7690 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7691 number of non-function entries in the vtable.
7693 It might seem that this function should never be called with a
7694 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7695 base is always subsumed by a derived class vtable. However, when
7696 we are building construction vtables, we do build vtables for
7697 primary bases; we need these while the primary base is being
7698 constructed. */
7700 static void
7702 tree orig_binfo,
7703 tree t,
7704 tree rtti_binfo,
7707 {
7708 tree v;
7709 vtbl_init_data vid;
7711 tree vbinfo;
7715 /* Initialize VID. */
7723 /* The first vbase or vcall offset is at index -3 in the vtable. */
7726 /* Add entries to the vtable for RTTI. */
7729 /* Create an array for keeping track of the functions we've
7730 processed. When we see multiple functions with the same
7731 signature, we share the vcall offsets. */
7733 /* Add the vcall and vbase offset entries. */
7736 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7737 build_vbase_offset_vtbl_entries. */
7742 /* If the target requires padding between data entries, add that now. */
7744 {
7750 /* Move data entries into their new positions and add padding
7751 after the new positions. Iterate backwards so we don't
7752 overwrite entries that we would need to process later. */
7755 ix--)
7756 {
7764 {
7769 null_pointer_node);
7770 }
7771 }
7772 }
7777 /* The initializers for virtual functions were built up in reverse
7778 order. Straighten them out and add them to the running list in one
7779 step. */
7789 /* Go through all the ordinary virtual functions, building up
7790 initializers. */
7792 {
7793 tree delta;
7794 tree vcall_index;
7801 {
7805 {
7808 }
7810 }
7812 /* If the only definition of this function signature along our
7813 primary base chain is from a lost primary, this vtable slot will
7814 never be used, so just zero it out. This is important to avoid
7815 requiring extra thunks which cannot be generated with the function.
7817 We first check this in update_vtable_entry_for_fn, so we handle
7818 restored primary bases properly; we also need to do it here so we
7819 zero out unused slots in ctor vtables, rather than filling them
7820 with erroneous values (though harmless, apart from relocation
7821 costs). */
7826 {
7827 /* Pull the offset for `this', and the function to call, out of
7828 the list. */
7835 /* You can't call an abstract virtual function; it's abstract.
7836 So, we replace these functions with __pure_virtual. */
7838 {
7843 }
7844 else
7845 {
7847 {
7851 }
7852 /* Take the address of the function, considering it to be of an
7853 appropriate generic type. */
7855 }
7856 }
7858 /* And add it to the chain of initializers. */
7860 {
7865 else
7867 {
7874 }
7875 }
7876 else
7878 }
7879 }
7881 /* Adds to vid->inits the initializers for the vbase and vcall
7882 offsets in BINFO, which is in the hierarchy dominated by T. */
7884 static void
7886 {
7887 tree b;
7889 /* If this is a derived class, we must first create entries
7890 corresponding to the primary base class. */
7895 /* Add the vbase entries for this base. */
7897 /* Add the vcall entries for this base. */
7899 }
7901 /* Returns the initializers for the vbase offset entries in the vtable
7902 for BINFO (which is part of the class hierarchy dominated by T), in
7903 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7904 where the next vbase offset will go. */
7906 static void
7908 {
7909 tree vbase;
7910 tree t;
7911 tree non_primary_binfo;
7913 /* If there are no virtual baseclasses, then there is nothing to
7914 do. */
7920 /* We might be a primary base class. Go up the inheritance hierarchy
7921 until we find the most derived class of which we are a primary base:
7922 it is the offset of that which we need to use. */
7925 {
7926 tree b;
7928 /* If we have reached a virtual base, then it must be a primary
7929 base (possibly multi-level) of vid->binfo, or we wouldn't
7930 have called build_vcall_and_vbase_vtbl_entries for it. But it
7931 might be a lost primary, so just skip down to vid->binfo. */
7933 {
7936 }
7942 }
7944 /* Go through the virtual bases, adding the offsets. */
7946 vbase;
7948 {
7949 tree b;
7950 tree delta;
7955 /* Find the instance of this virtual base in the complete
7956 object. */
7959 /* If we've already got an offset for this virtual base, we
7960 don't need another one. */
7965 /* Figure out where we can find this vbase offset. */
7974 /* The vbase offset had better be the same. */
7977 /* The next vbase will come at a more negative offset. */
7981 /* The initializer is the delta from BINFO to this virtual base.
7982 The vbase offsets go in reverse inheritance-graph order, and
7983 we are walking in inheritance graph order so these end up in
7984 the right order. */
7991 }
7992 }
7994 /* Adds the initializers for the vcall offset entries in the vtable
7995 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7996 to VID->INITS. */
7998 static void
8000 {
8001 /* We only need these entries if this base is a virtual base. We
8002 compute the indices -- but do not add to the vtable -- when
8003 building the main vtable for a class. */
8006 /* If BINFO is RTTI_BINFO, then (since BINFO does not
8007 correspond to VID->DERIVED), we are building a primary
8008 construction virtual table. Since this is a primary
8009 virtual table, we do not need the vcall offsets for
8010 BINFO. */
8012 {
8013 /* We need a vcall offset for each of the virtual functions in this
8014 vtable. For example:
8016 class A { virtual void f (); };
8017 class B1 : virtual public A { virtual void f (); };
8018 class B2 : virtual public A { virtual void f (); };
8019 class C: public B1, public B2 { virtual void f (); };
8021 A C object has a primary base of B1, which has a primary base of A. A
8022 C also has a secondary base of B2, which no longer has a primary base
8023 of A. So the B2-in-C construction vtable needs a secondary vtable for
8024 A, which will adjust the A* to a B2* to call f. We have no way of
8025 knowing what (or even whether) this offset will be when we define B2,
8026 so we store this "vcall offset" in the A sub-vtable and look it up in
8027 a "virtual thunk" for B2::f.
8029 We need entries for all the functions in our primary vtable and
8030 in our non-virtual bases' secondary vtables. */
8032 /* If we are just computing the vcall indices -- but do not need
8033 the actual entries -- not that. */
8036 /* Now, walk through the non-virtual bases, adding vcall offsets. */
8038 }
8039 }
8041 /* Build vcall offsets, starting with those for BINFO. */
8043 static void
8045 {
8047 tree primary_binfo;
8048 tree base_binfo;
8050 /* Don't walk into virtual bases -- except, of course, for the
8051 virtual base for which we are building vcall offsets. Any
8052 primary virtual base will have already had its offsets generated
8053 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8057 /* If BINFO has a primary base, process it first. */
8062 /* Add BINFO itself to the list. */
8065 /* Scan the non-primary bases of BINFO. */
8069 }
8071 /* Called from build_vcall_offset_vtbl_entries_r. */
8073 static void
8075 {
8076 /* Make entries for the rest of the virtuals. */
8078 {
8079 tree orig_fn;
8081 /* The ABI requires that the methods be processed in declaration
8082 order. G++ 3.2 used the order in the vtable. */
8084 orig_fn;
8088 }
8089 else
8090 {
8091 tree derived_virtuals;
8092 tree base_virtuals;
8093 tree orig_virtuals;
8094 /* If BINFO is a primary base, the most derived class which has
8095 BINFO as a primary base; otherwise, just BINFO. */
8096 tree non_primary_binfo;
8098 /* We might be a primary base class. Go up the inheritance hierarchy
8099 until we find the most derived class of which we are a primary base:
8100 it is the BINFO_VIRTUALS there that we need to consider. */
8103 {
8104 tree b;
8106 /* If we have reached a virtual base, then it must be vid->vbase,
8107 because we ignore other virtual bases in
8108 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8109 base (possibly multi-level) of vid->binfo, or we wouldn't
8110 have called build_vcall_and_vbase_vtbl_entries for it. But it
8111 might be a lost primary, so just skip down to vid->binfo. */
8113 {
8117 }
8123 }
8126 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8127 where rtti_binfo is the most derived type. */
8128 non_primary_binfo
8134 base_virtuals;
8138 {
8139 tree orig_fn;
8141 /* Find the declaration that originally caused this function to
8142 be present in BINFO_TYPE (binfo). */
8145 /* When processing BINFO, we only want to generate vcall slots for
8146 function slots introduced in BINFO. So don't try to generate
8147 one if the function isn't even defined in BINFO. */
8152 }
8153 }
8154 }
8156 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8158 static void
8160 {
8162 tree vcall_offset;
8163 tree derived_entry;
8165 /* If there is already an entry for a function with the same
8166 signature as FN, then we do not need a second vcall offset.
8167 Check the list of functions already present in the derived
8168 class vtable. */
8170 {
8172 /* We only use one vcall offset for virtual destructors,
8173 even though there are two virtual table entries. */
8177 }
8179 /* If we are building these vcall offsets as part of building
8180 the vtable for the most derived class, remember the vcall
8181 offset. */
8183 {
8186 NULL);
8189 }
8191 /* The next vcall offset will be found at a more negative
8192 offset. */
8196 /* Keep track of this function. */
8200 {
8201 tree base;
8202 tree fn;
8204 /* Find the overriding function. */
8208 integer_zero_node);
8209 else
8210 {
8213 /* The vbase we're working on is a primary base of
8214 vid->binfo. But it might be a lost primary, so its
8215 BINFO_OFFSET might be wrong, so we just use the
8216 BINFO_OFFSET from vid->binfo. */
8222 vcall_offset);
8223 }
8224 /* Add the initializer to the vtable. */
8226 }
8227 }
8229 /* Return vtbl initializers for the RTTI entries corresponding to the
8230 BINFO's vtable. The RTTI entries should indicate the object given
8231 by VID->rtti_binfo. */
8233 static void
8235 {
8236 tree b;
8237 tree t;
8238 tree offset;
8239 tree decl;
8240 tree init;
8244 /* To find the complete object, we will first convert to our most
8245 primary base, and then add the offset in the vtbl to that value. */
8249 {
8250 tree primary_base;
8256 }
8260 /* The second entry is the address of the typeinfo object. */
8263 else
8266 /* Convert the declaration to a type that can be stored in the
8267 vtable. */
8271 /* Add the offset-to-top entry. It comes earlier in the vtable than
8272 the typeinfo entry. Convert the offset to look like a
8273 function pointer, so that we can put it in the vtable. */
8276 }
8278 /* Fold a OBJ_TYPE_REF expression to the address of a function.
8279 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
8281 tree
8283 {
8287 tree fndecl;
8290 {
8291 i += (TARGET_VTABLE_USES_DESCRIPTORS
8294 }
8298 #ifdef ENABLE_CHECKING
8301 #endif
8306 }