| blob | a2ed86334b5ba53d91d15fcf21833e84df45638b |
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
1253 {
1256 tree base_binfo;
1257 tree binfo;
1269 {
1274 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1275 here because the case of virtual functions but non-virtual
1276 dtor is handled in finish_struct_1. */
1281 /* If the base class doesn't have copy constructors or
1282 assignment operators that take const references, then the
1283 derived class cannot have such a member automatically
1284 generated. */
1293 /* A virtual base does not effect nearly emptiness. */
1294 ;
1296 {
1298 /* And if there is more than one nearly empty base, then the
1299 derived class is not nearly empty either. */
1301 else
1302 /* Remember we've seen one. */
1304 }
1306 /* If the base class is not empty or nearly empty, then this
1307 class cannot be nearly empty. */
1310 /* A lot of properties from the bases also apply to the derived
1311 class. */
1329 /* A standard-layout class is a class that:
1330 ...
1331 * has no non-standard-layout base classes, */
1334 {
1335 tree basefield;
1336 /* ...has no base classes of the same type as the first non-static
1337 data member... */
1339 && (same_type_ignoring_top_level_qualifiers_p
1342 else
1343 /* ...either has no non-static data members in the most-derived
1344 class and at most one base class with non-static data
1345 members, or has no base classes with non-static data
1346 members */
1350 {
1353 else
1356 }
1357 }
1358 }
1359 }
1361 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1362 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1363 that have had a nearly-empty virtual primary base stolen by some
1364 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1365 T. */
1367 static void
1369 {
1373 tree base_binfo;
1375 /* Determine the primary bases of our bases. */
1378 {
1381 /* See if we're the non-virtual primary of our inheritance
1382 chain. */
1384 {
1391 /* We are the primary binfo. */
1393 }
1394 /* Determine if we have a virtual primary base, and mark it so.
1395 */
1397 {
1401 /* Someone already claimed this base. */
1403 else
1404 {
1405 tree delta;
1410 /* A virtual binfo might have been copied from within
1411 another hierarchy. As we're about to use it as a
1412 primary base, make sure the offsets match. */
1420 }
1421 }
1422 }
1424 /* First look for a dynamic direct non-virtual base. */
1426 {
1430 {
1433 }
1434 }
1436 /* A "nearly-empty" virtual base class can be the primary base
1437 class, if no non-virtual polymorphic base can be found. Look for
1438 a nearly-empty virtual dynamic base that is not already a primary
1439 base of something in the hierarchy. If there is no such base,
1440 just pick the first nearly-empty virtual base. */
1446 {
1448 {
1449 /* Found one that is not primary. */
1452 }
1454 /* Remember the first candidate. */
1456 }
1458 found:
1459 /* If we've got a primary base, use it. */
1461 {
1466 /* We are stealing a primary base. */
1470 {
1471 tree delta;
1474 /* A virtual binfo might have been copied from within
1475 another hierarchy. As we're about to use it as a primary
1476 base, make sure the offsets match. */
1481 }
1488 }
1489 }
1491 /* Update the variant types of T. */
1493 void
1495 {
1496 tree variants;
1502 variants;
1504 {
1505 /* These fields are in the _TYPE part of the node, not in
1506 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1516 /* Copy whatever these are holding today. */
1521 /* All variants of a class have the same attributes. */
1523 }
1524 }
1526 \f
1527 /* Set memoizing fields and bits of T (and its variants) for later
1528 use. */
1530 static void
1532 {
1533 /* Fix up variants (if any). */
1537 /* For a class w/o baseclasses, 'finish_struct' has set
1538 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1539 Similarly for a class whose base classes do not have vtables.
1540 When neither of these is true, we might have removed abstract
1541 virtuals (by providing a definition), added some (by declaring
1542 new ones), or redeclared ones from a base class. We need to
1543 recalculate what's really an abstract virtual at this point (by
1544 looking in the vtables). */
1547 /* If this type has a copy constructor or a destructor, force its
1548 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1549 nonzero. This will cause it to be passed by invisible reference
1550 and prevent it from being returned in a register. */
1553 {
1554 tree variants;
1557 {
1560 }
1561 }
1562 }
1564 /* Issue warnings about T having private constructors, but no friends,
1565 and so forth.
1567 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1568 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1569 non-private static member functions. */
1571 static void
1573 {
1576 tree fn;
1579 /* If the class has friends, those entities might create and
1580 access instances, so we should not warn. */
1583 /* We will have warned when the template was declared; there's
1584 no need to warn on every instantiation. */
1586 /* There's no reason to even consider warning about this
1587 class. */
1590 /* We only issue one warning, if more than one applies, because
1591 otherwise, on code like:
1593 class A {
1594 // Oops - forgot `public:'
1595 A();
1596 A(const A&);
1597 ~A();
1598 };
1600 we warn several times about essentially the same problem. */
1602 /* Check to see if all (non-constructor, non-destructor) member
1603 functions are private. (Since there are no friends or
1604 non-private statics, we can't ever call any of the private member
1605 functions.) */
1607 /* We're not interested in compiler-generated methods; they don't
1608 provide any way to call private members. */
1610 {
1612 {
1614 /* A non-private static member function is just like a
1615 friend; it can create and invoke private member
1616 functions, and be accessed without a class
1617 instance. */
1621 /* Keep searching for a static member function. */
1622 }
1625 }
1628 {
1629 /* There are no non-private methods, and there's at least one
1630 private member function that isn't a constructor or
1631 destructor. (If all the private members are
1632 constructors/destructors we want to use the code below that
1633 issues error messages specifically referring to
1634 constructors/destructors.) */
1640 {
1643 }
1645 {
1649 }
1650 }
1652 /* Even if some of the member functions are non-private, the class
1653 won't be useful for much if all the constructors or destructors
1654 are private: such an object can never be created or destroyed. */
1657 {
1660 t);
1662 }
1664 /* Warn about classes that have private constructors and no friends. */
1666 /* Implicitly generated constructors are always public. */
1669 {
1672 /* If a non-template class does not define a copy
1673 constructor, one is defined for it, enabling it to avoid
1674 this warning. For a template class, this does not
1675 happen, and so we would normally get a warning on:
1677 template <class T> class C { private: C(); };
1679 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1680 complete non-template or fully instantiated classes have this
1681 flag set. */
1684 else
1686 {
1688 /* Ideally, we wouldn't count copy constructors (or, in
1689 fact, any constructor that takes an argument of the
1690 class type as a parameter) because such things cannot
1691 be used to construct an instance of the class unless
1692 you already have one. But, for now at least, we're
1693 more generous. */
1695 {
1698 }
1699 }
1702 {
1705 t);
1707 }
1708 }
1709 }
1712 gt_pointer_operator new_value;
1716 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1718 static int
1720 {
1733 }
1735 /* This routine compares two fields like method_name_cmp but using the
1736 pointer operator in resort_field_decl_data. */
1738 static int
1740 {
1749 {
1756 }
1758 }
1760 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1762 void
1765 gt_pointer_operator new_value,
1767 {
1771 tree fn;
1773 /* The type conversion ops have to live at the front of the vec, so we
1774 can't sort them. */
1782 {
1786 resort_method_name_cmp);
1787 }
1788 }
1790 /* Warn about duplicate methods in fn_fields.
1792 Sort methods that are not special (i.e., constructors, destructors,
1793 and type conversion operators) so that we can find them faster in
1794 search. */
1796 static void
1798 {
1799 tree fn_fields;
1809 /* Clear DECL_IN_AGGR_P for all functions. */
1814 /* Issue warnings about private constructors and such. If there are
1815 no methods, then some public defaults are generated. */
1818 /* The type conversion ops have to live at the front of the vec, so we
1819 can't sort them. */
1828 }
1830 /* Make BINFO's vtable have N entries, including RTTI entries,
1831 vbase and vcall offsets, etc. Set its type and call the back end
1832 to lay it out. */
1834 static void
1836 {
1837 tree atype;
1838 tree vtable;
1844 /* We may have to grow the vtable. */
1847 {
1851 }
1852 }
1854 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1855 have the same signature. */
1857 int
1859 {
1860 /* One destructor overrides another if they are the same kind of
1861 destructor. */
1865 /* But a non-destructor never overrides a destructor, nor vice
1866 versa, nor do different kinds of destructors override
1867 one-another. For example, a complete object destructor does not
1868 override a deleting destructor. */
1877 {
1885 }
1887 }
1889 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1890 subobject. */
1892 static bool
1894 {
1895 tree probe;
1898 {
1902 /* If we meet a virtual base, we can't follow the inheritance
1903 any more. See if the complete type of DERIVED contains
1904 such a virtual base. */
1907 }
1909 }
1912 /* The function for which we are trying to find a final overrider. */
1913 tree fn;
1914 /* The base class in which the function was declared. */
1915 tree declaring_base;
1916 /* The candidate overriders. */
1917 tree candidates;
1918 /* Path to most derived. */
1922 /* Add the overrider along the current path to FFOD->CANDIDATES.
1923 Returns true if an overrider was found; false otherwise. */
1925 static bool
1929 {
1930 tree method;
1932 /* If BINFO is not the most derived type, try a more derived class.
1933 A definition there will overrider a definition here. */
1935 {
1936 depth--;
1940 }
1944 {
1947 /* Remove any candidates overridden by this new function. */
1949 {
1950 /* If *CANDIDATE overrides METHOD, then METHOD
1951 cannot override anything else on the list. */
1954 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1957 else
1959 }
1961 /* Add the new function. */
1964 }
1967 }
1969 /* Called from find_final_overrider via dfs_walk. */
1971 static tree
1973 {
1981 }
1983 static tree
1985 {
1990 }
1992 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1993 FN and whose TREE_VALUE is the binfo for the base where the
1994 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1995 DERIVED) is the base object in which FN is declared. */
1997 static tree
1999 {
2000 find_final_overrider_data ffod;
2002 /* Getting this right is a little tricky. This is valid:
2004 struct S { virtual void f (); };
2005 struct T { virtual void f (); };
2006 struct U : public S, public T { };
2008 even though calling `f' in `U' is ambiguous. But,
2010 struct R { virtual void f(); };
2011 struct S : virtual public R { virtual void f (); };
2012 struct T : virtual public R { virtual void f (); };
2013 struct U : public S, public T { };
2015 is not -- there's no way to decide whether to put `S::f' or
2016 `T::f' in the vtable for `R'.
2018 The solution is to look at all paths to BINFO. If we find
2019 different overriders along any two, then there is a problem. */
2023 /* Determine the depth of the hierarchy. */
2034 /* If there was no winner, issue an error message. */
2039 }
2041 /* Return the index of the vcall offset for FN when TYPE is used as a
2042 virtual base. */
2044 static tree
2046 {
2048 tree_pair_p p;
2056 /* There should always be an appropriate index. */
2058 }
2060 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2061 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
2062 corresponding position in the BINFO_VIRTUALS list. */
2064 static void
2067 {
2068 tree b;
2069 tree overrider;
2070 tree delta;
2071 tree virtual_base;
2072 tree first_defn;
2078 /* Find the nearest primary base (possibly binfo itself) which defines
2079 this function; this is the class the caller will convert to when
2080 calling FN through BINFO. */
2082 {
2087 /* The nearest definition is from a lost primary. */
2090 }
2093 /* Find the final overrider. */
2096 {
2099 }
2102 /* Check for adjusting covariant return types. */
2110 /* If the overrider is invalid, don't even try. */
2112 {
2113 /* If FN is a covariant thunk, we must figure out the adjustment
2114 to the final base FN was converting to. As OVERRIDER_TARGET might
2115 also be converting to the return type of FN, we have to
2116 combine the two conversions here. */
2123 {
2127 }
2128 else
2132 /* Find the equivalent binfo within the return type of the
2133 overriding function. We will want the vbase offset from
2134 there. */
2136 over_return);
2139 {
2140 /* There was no existing virtual thunk (which takes
2141 precedence). So find the binfo of the base function's
2142 return type within the overriding function's return type.
2143 We cannot call lookup base here, because we're inside a
2144 dfs_walk, and will therefore clobber the BINFO_MARKED
2145 flags. Fortunately we know the covariancy is valid (it
2146 has already been checked), so we can just iterate along
2147 the binfos, which have been chained in inheritance graph
2148 order. Of course it is lame that we have to repeat the
2149 search here anyway -- we should really be caching pieces
2150 of the vtable and avoiding this repeated work. */
2153 /* Find the base binfo within the overriding function's
2154 return type. We will always find a thunk_binfo, except
2155 when the covariancy is invalid (which we will have
2156 already diagnosed). */
2159 thunk_binfo;
2165 /* See if virtual inheritance is involved. */
2167 virtual_offset;
2174 {
2178 {
2179 /* We convert via virtual base. Adjust the fixed
2180 offset to be from there. */
2181 offset =
2185 }
2187 /* There was an existing fixed offset, this must be
2188 from the base just converted to, and the base the
2189 FN was thunking to. */
2191 else
2193 }
2194 }
2197 /* Replace the overriding function with a covariant thunk. We
2198 will emit the overriding function in its own slot as
2199 well. */
2202 }
2203 else
2207 /* Assume that we will produce a thunk that convert all the way to
2208 the final overrider, and not to an intermediate virtual base. */
2211 /* See if we can convert to an intermediate virtual base first, and then
2212 use the vcall offset located there to finish the conversion. */
2214 {
2215 /* If we find the final overrider, then we can stop
2216 walking. */
2221 /* If we find a virtual base, and we haven't yet found the
2222 overrider, then there is a virtual base between the
2223 declaring base (first_defn) and the final overrider. */
2225 {
2228 }
2229 }
2232 {
2233 /* The ABI specifies that a covariant thunk includes a mangling
2234 for a this pointer adjustment. This-adjusting thunks that
2235 override a function from a virtual base have a vcall
2236 adjustment. When the virtual base in question is a primary
2237 virtual base, we know the adjustments are zero, (and in the
2238 non-covariant case, we would not use the thunk).
2239 Unfortunately we didn't notice this could happen, when
2240 designing the ABI and so never mandated that such a covariant
2241 thunk should be emitted. Because we must use the ABI mandated
2242 name, we must continue searching from the binfo where we
2243 found the most recent definition of the function, towards the
2244 primary binfo which first introduced the function into the
2245 vtable. If that enters a virtual base, we must use a vcall
2246 this-adjusting thunk. Bleah! */
2255 /* Even if we find a virtual base, the correct delta is
2256 between the overrider and the binfo we're building a vtable
2257 for. */
2259 }
2261 /* Compute the constant adjustment to the `this' pointer. The
2262 `this' pointer, when this function is called, will point at BINFO
2263 (or one of its primary bases, which are at the same offset). */
2265 /* The `this' pointer needs to be adjusted from the declaration to
2266 the nearest virtual base. */
2271 /* If the nearest definition is in a lost primary, we don't need an
2272 entry in our vtable. Except possibly in a constructor vtable,
2273 if we happen to get our primary back. In that case, the offset
2274 will be zero, as it will be a primary base. */
2276 else
2277 /* The `this' pointer needs to be adjusted from pointing to
2278 BINFO to pointing at the base where the final overrider
2279 appears. */
2280 virtual_covariant:
2291 else
2293 }
2295 /* Called from modify_all_vtables via dfs_walk. */
2297 static tree
2299 {
2301 tree virtuals;
2302 tree old_virtuals;
2306 /* A base without a vtable needs no modification, and its bases
2307 are uninteresting. */
2312 /* Don't do the primary vtable, if it's new. */
2316 /* There's no need to modify the vtable for a non-virtual primary
2317 base; we're not going to use that vtable anyhow. We do still
2318 need to do this for virtual primary bases, as they could become
2319 non-primary in a construction vtable. */
2324 /* Now, go through each of the virtual functions in the virtual
2325 function table for BINFO. Find the final overrider, and update
2326 the BINFO_VIRTUALS list appropriately. */
2329 virtuals;
2333 binfo,
2338 }
2340 /* Update all of the primary and secondary vtables for T. Create new
2341 vtables as required, and initialize their RTTI information. Each
2342 of the functions in VIRTUALS is declared in T and may override a
2343 virtual function from a base class; find and modify the appropriate
2344 entries to point to the overriding functions. Returns a list, in
2345 declaration order, of the virtual functions that are declared in T,
2346 but do not appear in the primary base class vtable, and which
2347 should therefore be appended to the end of the vtable for T. */
2349 static tree
2351 {
2355 /* Update all of the vtables. */
2358 /* Add virtual functions not already in our primary vtable. These
2359 will be both those introduced by this class, and those overridden
2360 from secondary bases. It does not include virtuals merely
2361 inherited from secondary bases. */
2363 {
2368 {
2369 /* We don't need to adjust the `this' pointer when
2370 calling this function. */
2374 /* This is a function not already in our vtable. Keep it. */
2376 }
2377 else
2378 /* We've already got an entry for this function. Skip it. */
2380 }
2383 }
2385 /* Get the base virtual function declarations in T that have the
2386 indicated NAME. */
2388 static tree
2390 {
2391 tree methods;
2396 /* Find virtual functions in T with the indicated NAME. */
2400 methods;
2402 {
2408 }
2414 {
2417 base_fndecls);
2418 }
2421 }
2423 /* If this declaration supersedes the declaration of
2424 a method declared virtual in the base class, then
2425 mark this field as being virtual as well. */
2427 void
2429 {
2431 /* In [temp.mem] we have:
2433 A specialization of a member function template does not
2434 override a virtual function from a base class. */
2441 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2442 the error_mark_node so that we know it is an overriding
2443 function. */
2447 {
2451 }
2452 }
2454 /* Warn about hidden virtual functions that are not overridden in t.
2455 We know that constructors and destructors don't apply. */
2457 static void
2459 {
2461 tree fns;
2464 /* We go through each separately named virtual function. */
2468 {
2469 tree fn;
2470 tree name;
2471 tree fndecl;
2472 tree base_fndecls;
2473 tree base_binfo;
2474 tree binfo;
2477 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2478 have the same name. Figure out what name that is. */
2480 /* There are no possibly hidden functions yet. */
2482 /* Iterate through all of the base classes looking for possibly
2483 hidden functions. */
2486 {
2489 base_fndecls);
2490 }
2492 /* If there are no functions to hide, continue. */
2496 /* Remove any overridden functions. */
2498 {
2501 {
2505 /* If the method from the base class has the same
2506 signature as the method from the derived class, it
2507 has been overridden. */
2510 else
2512 }
2513 }
2515 /* Now give a warning for all base functions without overriders,
2516 as they are hidden. */
2518 {
2519 /* Here we know it is a hider, and no overrider exists. */
2523 }
2524 }
2525 }
2527 /* Check for things that are invalid. There are probably plenty of other
2528 things we should check for also. */
2530 static void
2532 {
2533 tree field;
2536 {
2544 {
2548 {
2549 /* We're generally only interested in entities the user
2550 declared, but we also find nested classes by noticing
2551 the TYPE_DECL that we create implicitly. You're
2552 allowed to put one anonymous union inside another,
2553 though, so we explicitly tolerate that. We use
2554 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2555 we also allow unnamed types used for defining fields. */
2562 {
2566 else
2570 }
2573 {
2576 else
2578 }
2580 {
2583 else
2585 }
2589 }
2590 }
2591 }
2592 }
2594 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2595 will be used later during class template instantiation.
2596 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2597 a non-static member data (FIELD_DECL), a member function
2598 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2599 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2600 When FRIEND_P is nonzero, T is either a friend class
2601 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2602 (FUNCTION_DECL, TEMPLATE_DECL). */
2604 void
2606 {
2607 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2612 }
2614 /* Create default constructors, assignment operators, and so forth for
2615 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2616 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2617 the class cannot have a default constructor, copy constructor
2618 taking a const reference argument, or an assignment operator taking
2619 a const reference, respectively. */
2621 static void
2625 {
2626 /* Destructor. */
2628 {
2629 /* In general, we create destructors lazily. */
2634 /* But if this is a Java class, any non-trivial destructor is
2635 invalid, even if compiler-generated. Therefore, if the
2636 destructor is non-trivial we create it now. */
2638 }
2640 /* [class.ctor]
2642 If there is no user-declared constructor for a class, a default
2643 constructor is implicitly declared. */
2645 {
2648 }
2650 /* [class.ctor]
2652 If a class definition does not explicitly declare a copy
2653 constructor, one is declared implicitly. */
2656 {
2662 }
2664 /* If there is no assignment operator, one will be created if and
2665 when it is needed. For now, just record whether or not the type
2666 of the parameter to the assignment operator will be a const or
2667 non-const reference. */
2670 {
2676 }
2678 /* We can't be lazy about declaring functions that might override
2679 a virtual function from a base class. */
2684 {
2686 tree base_binfo;
2690 {
2691 tree bv;
2693 {
2696 {
2701 }
2705 }
2706 }
2707 }
2708 }
2710 /* Subroutine of finish_struct_1. Recursively count the number of fields
2711 in TYPE, including anonymous union members. */
2713 static int
2715 {
2716 tree x;
2719 {
2722 else
2724 }
2726 }
2728 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2729 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2731 static int
2733 {
2734 tree x;
2736 {
2739 else
2741 }
2743 }
2745 /* FIELD is a bit-field. We are finishing the processing for its
2746 enclosing type. Issue any appropriate messages and set appropriate
2747 flags. Returns false if an error has been diagnosed. */
2749 static bool
2751 {
2753 tree w;
2755 /* Extract the declared width of the bitfield, which has been
2756 temporarily stashed in DECL_INITIAL. */
2759 /* Remove the bit-field width indicator so that the rest of the
2760 compiler does not treat that value as an initializer. */
2763 /* Detect invalid bit-field type. */
2765 {
2768 }
2769 else
2770 {
2771 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2774 /* detect invalid field size. */
2778 {
2781 }
2783 {
2786 }
2788 {
2791 }
2800 }
2803 {
2807 }
2808 else
2809 {
2810 /* Non-bit-fields are aligned for their type. */
2814 }
2815 }
2817 /* FIELD is a non bit-field. We are finishing the processing for its
2818 enclosing type T. Issue any appropriate messages and set appropriate
2819 flags. */
2821 static void
2823 tree t,
2827 {
2830 /* An anonymous union cannot contain any fields which would change
2831 the settings of CANT_HAVE_CONST_CTOR and friends. */
2833 ;
2834 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2835 structs. So, we recurse through their fields here. */
2837 {
2838 tree fields;
2844 }
2845 /* Check members with class type for constructors, destructors,
2846 etc. */
2848 {
2849 /* Never let anything with uninheritable virtuals
2850 make it through without complaint. */
2854 {
2857 field);
2862 field);
2863 /* Don't bother diagnosing move assop now; C++0x has more
2864 flexible unions. */
2865 }
2866 else
2867 {
2880 }
2889 }
2891 {
2892 /* `build_class_init_list' does not recognize
2893 non-FIELD_DECLs. */
2897 }
2898 }
2900 /* Check the data members (both static and non-static), class-scoped
2901 typedefs, etc., appearing in the declaration of T. Issue
2902 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2903 declaration order) of access declarations; each TREE_VALUE in this
2904 list is a USING_DECL.
2906 In addition, set the following flags:
2908 EMPTY_P
2909 The class is empty, i.e., contains no non-static data members.
2911 CANT_HAVE_CONST_CTOR_P
2912 This class cannot have an implicitly generated copy constructor
2913 taking a const reference.
2915 CANT_HAVE_CONST_ASN_REF
2916 This class cannot have an implicitly generated assignment
2917 operator taking a const reference.
2919 All of these flags should be initialized before calling this
2920 function.
2922 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2923 fields can be added by adding to this chain. */
2925 static void
2929 {
2937 /* Assume there are no access declarations. */
2939 /* Assume this class has no pointer members. */
2941 /* Assume none of the members of this class have default
2942 initializations. */
2946 {
2954 {
2955 /* Prune the access declaration from the list of fields. */
2958 /* Save the access declarations for our caller. */
2961 /* Since we've reset *FIELD there's no reason to skip to the
2962 next field. */
2965 }
2971 /* If we've gotten this far, it's a data member, possibly static,
2972 or an enumerator. */
2975 /* When this goes into scope, it will be a non-local reference. */
2979 {
2980 /* [class.union]
2982 If a union contains a static data member, or a member of
2983 reference type, the program is ill-formed. */
2985 {
2988 }
2990 {
2995 }
2996 }
2998 /* Perform error checking that did not get done in
2999 grokdeclarator. */
3001 {
3005 }
3007 {
3011 }
3019 /* Now it can only be a FIELD_DECL. */
3024 /* A standard-layout class is a class that:
3025 ...
3026 has the same access control (Clause 11) for all non-static data members,
3027 ... */
3034 /* If this is of reference type, check if it needs an init. */
3036 {
3042 /* ARM $12.6.2: [A member initializer list] (or, for an
3043 aggregate, initialization by a brace-enclosed list) is the
3044 only way to initialize nonstatic const and reference
3045 members. */
3048 }
3053 {
3055 {
3056 warning
3059 x);
3061 }
3065 }
3068 /* We don't treat zero-width bitfields as making a class
3069 non-empty. */
3070 ;
3071 else
3072 {
3073 /* The class is non-empty. */
3075 /* The class is not even nearly empty. */
3077 /* If one of the data members contains an empty class,
3078 so does T. */
3082 }
3084 /* This is used by -Weffc++ (see below). Warn only for pointers
3085 to members which might hold dynamic memory. So do not warn
3086 for pointers to functions or pointers to members. */
3093 {
3098 }
3104 /* DR 148 now allows pointers to members (which are POD themselves),
3105 to be allowed in POD structs. */
3114 /* We set DECL_C_BIT_FIELD in grokbitfield.
3115 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3118 cant_have_const_ctor_p,
3119 no_const_asn_ref_p,
3122 /* If any field is const, the structure type is pseudo-const. */
3124 {
3129 /* ARM $12.6.2: [A member initializer list] (or, for an
3130 aggregate, initialization by a brace-enclosed list) is the
3131 only way to initialize nonstatic const and reference
3132 members. */
3135 }
3136 /* A field that is pseudo-const makes the structure likewise. */
3138 {
3143 }
3145 /* Core issue 80: A nonstatic data member is required to have a
3146 different name from the class iff the class has a
3147 user-declared constructor. */
3151 }
3153 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3154 it should also define a copy constructor and an assignment operator to
3155 implement the correct copy semantic (deep vs shallow, etc.). As it is
3156 not feasible to check whether the constructors do allocate dynamic memory
3157 and store it within members, we approximate the warning like this:
3159 -- Warn only if there are members which are pointers
3160 -- Warn only if there is a non-trivial constructor (otherwise,
3161 there cannot be memory allocated).
3162 -- Warn only if there is a non-trivial destructor. We assume that the
3163 user at least implemented the cleanup correctly, and a destructor
3164 is needed to free dynamic memory.
3166 This seems enough for practical purposes. */
3168 && has_pointers
3172 {
3176 {
3181 }
3185 }
3187 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3191 /* Check anonymous struct/anonymous union fields. */
3194 /* We've built up the list of access declarations in reverse order.
3195 Fix that now. */
3197 }
3199 /* If TYPE is an empty class type, records its OFFSET in the table of
3200 OFFSETS. */
3202 static int
3204 {
3205 splay_tree_node n;
3210 /* Record the location of this empty object in OFFSETS. */
3218 type,
3222 }
3224 /* Returns nonzero if TYPE is an empty class type and there is
3225 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3227 static int
3229 {
3230 splay_tree_node n;
3231 tree t;
3236 /* Record the location of this empty object in OFFSETS. */
3246 }
3248 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3249 F for every subobject, passing it the type, offset, and table of
3250 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3251 be traversed.
3253 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3254 than MAX_OFFSET will not be walked.
3256 If F returns a nonzero value, the traversal ceases, and that value
3257 is returned. Otherwise, returns zero. */
3259 static int
3261 subobject_offset_fn f,
3262 tree offset,
3263 splay_tree offsets,
3264 tree max_offset,
3266 {
3270 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3271 stop. */
3279 {
3283 }
3286 {
3287 tree field;
3288 tree binfo;
3291 /* Avoid recursing into objects that are not interesting. */
3295 /* Record the location of TYPE. */
3300 /* Iterate through the direct base classes of TYPE. */
3304 {
3305 tree binfo_offset;
3318 offset,
3320 else
3321 {
3322 tree orig_binfo;
3323 /* We cannot rely on BINFO_OFFSET being set for the base
3324 class yet, but the offsets for direct non-virtual
3325 bases can be calculated by going back to the TYPE. */
3328 offset,
3330 }
3333 f,
3334 binfo_offset,
3335 offsets,
3336 max_offset,
3341 }
3344 {
3348 /* Iterate through the virtual base classes of TYPE. In G++
3349 3.2, we included virtual bases in the direct base class
3350 loop above, which results in incorrect results; the
3351 correct offsets for virtual bases are only known when
3352 working with the most derived type. */
3356 {
3358 f,
3360 offset,
3362 offsets,
3363 max_offset,
3367 }
3368 else
3369 {
3370 /* We still have to walk the primary base, if it is
3371 virtual. (If it is non-virtual, then it was walked
3372 above.) */
3378 {
3379 r = (walk_subobject_offsets
3384 }
3385 }
3386 }
3388 /* Iterate through the fields of TYPE. */
3391 {
3392 tree field_offset;
3396 else
3397 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3401 f,
3403 offset,
3404 field_offset),
3405 offsets,
3406 max_offset,
3410 }
3411 }
3413 {
3416 tree index;
3418 /* Avoid recursing into objects that are not interesting. */
3423 /* Step through each of the elements in the array. */
3425 /* G++ 3.2 had an off-by-one error here. */
3430 {
3432 f,
3433 offset,
3434 offsets,
3435 max_offset,
3441 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3442 there's no point in iterating through the remaining
3443 elements of the array. */
3446 }
3447 }
3450 }
3452 /* Record all of the empty subobjects of TYPE (either a type or a
3453 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3454 is being placed at OFFSET; otherwise, it is a base class that is
3455 being placed at OFFSET. */
3457 static void
3459 tree offset,
3460 splay_tree offsets,
3462 {
3463 tree max_offset;
3464 /* If recording subobjects for a non-static data member or a
3465 non-empty base class , we do not need to record offsets beyond
3466 the size of the biggest empty class. Additional data members
3467 will go at the end of the class. Additional base classes will go
3468 either at offset zero (if empty, in which case they cannot
3469 overlap with offsets past the size of the biggest empty class) or
3470 at the end of the class.
3472 However, if we are placing an empty base class, then we must record
3473 all offsets, as either the empty class is at offset zero (where
3474 other empty classes might later be placed) or at the end of the
3475 class (where other objects might then be placed, so other empty
3476 subobjects might later overlap). */
3480 else
3484 }
3486 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3487 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3488 virtual bases of TYPE are examined. */
3490 static int
3492 tree offset,
3493 splay_tree offsets,
3495 {
3496 splay_tree_node max_node;
3498 /* Get the node in OFFSETS that indicates the maximum offset where
3499 an empty subobject is located. */
3501 /* If there aren't any empty subobjects, then there's no point in
3502 performing this check. */
3508 vbases_p);
3509 }
3511 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3512 non-static data member of the type indicated by RLI. BINFO is the
3513 binfo corresponding to the base subobject, OFFSETS maps offsets to
3514 types already located at those offsets. This function determines
3515 the position of the DECL. */
3517 static void
3519 tree decl,
3520 tree binfo,
3521 splay_tree offsets)
3522 {
3525 tree type;
3528 {
3529 /* For the purposes of determining layout conflicts, we want to
3530 use the class type of BINFO; TREE_TYPE (DECL) will be the
3531 CLASSTYPE_AS_BASE version, which does not contain entries for
3532 zero-sized bases. */
3535 }
3536 else
3537 {
3540 }
3542 /* Try to place the field. It may take more than one try if we have
3543 a hard time placing the field without putting two objects of the
3544 same type at the same address. */
3546 {
3549 /* Place this field. */
3553 /* We have to check to see whether or not there is already
3554 something of the same type at the offset we're about to use.
3555 For example, consider:
3557 struct S {};
3558 struct T : public S { int i; };
3559 struct U : public S, public T {};
3561 Here, we put S at offset zero in U. Then, we can't put T at
3562 offset zero -- its S component would be at the same address
3563 as the S we already allocated. So, we have to skip ahead.
3564 Since all data members, including those whose type is an
3565 empty class, have nonzero size, any overlap can happen only
3566 with a direct or indirect base-class -- it can't happen with
3567 a data member. */
3568 /* In a union, overlap is permitted; all members are placed at
3569 offset zero. */
3572 /* G++ 3.2 did not check for overlaps when placing a non-empty
3573 virtual base. */
3578 {
3579 /* Strip off the size allocated to this field. That puts us
3580 at the first place we could have put the field with
3581 proper alignment. */
3584 /* Bump up by the alignment required for the type. */
3585 rli->bitpos
3591 }
3592 else
3593 /* There was no conflict. We're done laying out this field. */
3595 }
3597 /* Now that we know where it will be placed, update its
3598 BINFO_OFFSET. */
3600 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3601 this point because their BINFO_OFFSET is copied from another
3602 hierarchy. Therefore, we may not need to add the entire
3603 OFFSET. */
3609 }
3611 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3613 static int
3615 tree offset,
3616 splay_tree offsets ATTRIBUTE_UNUSED)
3617 {
3619 }
3621 /* Layout the empty base BINFO. EOC indicates the byte currently just
3622 past the end of the class, and should be correctly aligned for a
3623 class of the type indicated by BINFO; OFFSETS gives the offsets of
3624 the empty bases allocated so far. T is the most derived
3625 type. Return nonzero iff we added it at the end. */
3627 static bool
3630 {
3631 tree alignment;
3635 /* This routine should only be used for empty classes. */
3640 {
3642 propagate_binfo_offsets
3645 else
3647 "offset of empty base %qT may not be ABI-compliant and may"
3650 }
3652 /* This is an empty base class. We first try to put it at offset
3653 zero. */
3656 offsets,
3658 {
3659 /* That didn't work. Now, we move forward from the next
3660 available spot in the class. */
3664 {
3667 offsets,
3669 /* We finally found a spot where there's no overlap. */
3672 /* There's overlap here, too. Bump along to the next spot. */
3674 }
3675 }
3678 {
3683 }
3686 }
3688 /* Layout the base given by BINFO in the class indicated by RLI.
3689 *BASE_ALIGN is a running maximum of the alignments of
3690 any base class. OFFSETS gives the location of empty base
3691 subobjects. T is the most derived type. Return nonzero if the new
3692 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3693 *NEXT_FIELD, unless BINFO is for an empty base class.
3695 Returns the location at which the next field should be inserted. */
3700 {
3705 /* This error is now reported in xref_tag, thus giving better
3706 location information. */
3709 /* Place the base class. */
3711 {
3712 tree decl;
3714 /* The containing class is non-empty because it has a non-empty
3715 base class. */
3718 /* Create the FIELD_DECL. */
3725 {
3733 /* Try to place the field. It may take more than one try if we
3734 have a hard time placing the field without putting two
3735 objects of the same type at the same address. */
3737 /* Add the new FIELD_DECL to the list of fields for T. */
3741 }
3742 }
3743 else
3744 {
3745 tree eoc;
3748 /* On some platforms (ARM), even empty classes will not be
3749 byte-aligned. */
3754 /* A nearly-empty class "has no proper base class that is empty,
3755 not morally virtual, and at an offset other than zero." */
3757 {
3760 /* The check above (used in G++ 3.2) is insufficient because
3761 an empty class placed at offset zero might itself have an
3762 empty base at a nonzero offset. */
3764 empty_base_at_nonzero_offset_p,
3765 size_zero_node,
3769 {
3772 else
3774 "class %qT will be considered nearly empty in a "
3776 }
3777 }
3779 /* We do not create a FIELD_DECL for empty base classes because
3780 it might overlap some other field. We want to be able to
3781 create CONSTRUCTORs for the class by iterating over the
3782 FIELD_DECLs, and the back end does not handle overlapping
3783 FIELD_DECLs. */
3785 /* An empty virtual base causes a class to be non-empty
3786 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3787 here because that was already done when the virtual table
3788 pointer was created. */
3789 }
3791 /* Record the offsets of BINFO and its base subobjects. */
3794 offsets,
3798 }
3800 /* Layout all of the non-virtual base classes. Record empty
3801 subobjects in OFFSETS. T is the most derived type. Return nonzero
3802 if the type cannot be nearly empty. The fields created
3803 corresponding to the base classes will be inserted at
3804 *NEXT_FIELD. */
3806 static void
3809 {
3810 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3811 subobjects. */
3816 /* The primary base class is always allocated first. */
3821 /* Now allocate the rest of the bases. */
3823 {
3824 tree base_binfo;
3828 /* The primary base was already allocated above, so we don't
3829 need to allocate it again here. */
3833 /* Virtual bases are added at the end (a primary virtual base
3834 will have already been added). */
3840 }
3841 }
3843 /* Go through the TYPE_METHODS of T issuing any appropriate
3844 diagnostics, figuring out which methods override which other
3845 methods, and so forth. */
3847 static void
3849 {
3850 tree x;
3853 {
3857 /* The name of the field is the original field name
3858 Save this in auxiliary field for later overloading. */
3860 {
3864 }
3865 /* All user-provided destructors are non-trivial.
3866 Constructors and assignment ops are handled in
3867 grok_special_member_properties. */
3870 }
3871 }
3873 /* FN is a constructor or destructor. Clone the declaration to create
3874 a specialized in-charge or not-in-charge version, as indicated by
3875 NAME. */
3877 static tree
3879 {
3880 tree parms;
3881 tree clone;
3883 /* Copy the function. */
3885 /* Reset the function name. */
3888 /* Remember where this function came from. */
3890 /* Make it easy to find the CLONE given the FN. */
3894 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3896 {
3903 }
3906 /* There's no pending inline data for this function. */
3910 /* The base-class destructor is not virtual. */
3912 {
3916 }
3918 /* If there was an in-charge parameter, drop it from the function
3919 type. */
3921 {
3922 tree basetype;
3923 tree parmtypes;
3924 tree exceptions;
3929 /* Skip the `this' parameter. */
3931 /* Skip the in-charge parameter. */
3933 /* And the VTT parm, in a complete [cd]tor. */
3937 /* If this is subobject constructor or destructor, add the vtt
3938 parameter. */
3942 parmtypes);
3945 exceptions);
3949 }
3951 /* Copy the function parameters. */
3953 /* Remove the in-charge parameter. */
3955 {
3959 }
3960 /* And the VTT parm, in a complete [cd]tor. */
3962 {
3965 else
3966 {
3970 }
3971 }
3974 {
3977 }
3979 /* Create the RTL for this function. */
3987 }
3989 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
3990 not invoke this function directly.
3992 For a non-thunk function, returns the address of the slot for storing
3993 the function it is a clone of. Otherwise returns NULL_TREE.
3995 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
3996 cloned_function is unset. This is to support the separate
3997 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
3998 on a template makes sense, but not the former. */
4000 tree *
4002 {
4010 {
4011 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4014 else
4015 #endif
4017 }
4022 else
4024 }
4026 /* Produce declarations for all appropriate clones of FN. If
4027 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4028 CLASTYPE_METHOD_VEC as well. */
4030 void
4032 {
4033 tree clone;
4035 /* Avoid inappropriate cloning. */
4041 {
4042 /* For each constructor, we need two variants: an in-charge version
4043 and a not-in-charge version. */
4050 }
4051 else
4052 {
4055 /* For each destructor, we need three variants: an in-charge
4056 version, a not-in-charge version, and an in-charge deleting
4057 version. We clone the deleting version first because that
4058 means it will go second on the TYPE_METHODS list -- and that
4059 corresponds to the correct layout order in the virtual
4060 function table.
4062 For a non-virtual destructor, we do not build a deleting
4063 destructor. */
4065 {
4069 }
4076 }
4078 /* Note that this is an abstract function that is never emitted. */
4080 }
4082 /* DECL is an in charge constructor, which is being defined. This will
4083 have had an in class declaration, from whence clones were
4084 declared. An out-of-class definition can specify additional default
4085 arguments. As it is the clones that are involved in overload
4086 resolution, we must propagate the information from the DECL to its
4087 clones. */
4089 void
4091 {
4092 tree clone;
4096 {
4103 /* Skip the 'this' parameter. */
4119 {
4124 {
4125 /* A default parameter has been added. Adjust the
4126 clone's parameters. */
4130 tree type;
4135 {
4138 clone_parms);
4140 }
4143 clone_parms);
4152 }
4153 }
4155 }
4156 }
4158 /* For each of the constructors and destructors in T, create an
4159 in-charge and not-in-charge variant. */
4161 static void
4163 {
4164 tree fns;
4166 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4167 out now. */
4175 }
4177 /* Returns true iff class T has a user-defined constructor other than
4178 the default constructor. */
4180 bool
4182 {
4183 tree fns;
4189 {
4196 }
4199 }
4201 /* Returns the defaulted constructor if T has one. Otherwise, returns
4202 NULL_TREE. */
4204 tree
4206 {
4213 {
4217 {
4223 }
4224 }
4227 }
4229 /* Returns true iff FN is a user-provided function, i.e. user-declared
4230 and not defaulted at its first declaration; or explicit, private,
4231 protected, or non-const. */
4233 bool
4235 {
4238 else
4241 }
4243 /* Returns true iff class T has a user-provided constructor. */
4245 bool
4247 {
4248 tree fns;
4256 /* This can happen in error cases; avoid crashing. */
4265 }
4267 /* Returns true iff class T has a user-provided default constructor. */
4269 bool
4271 {
4272 tree fns;
4278 {
4284 }
4287 }
4289 /* Returns true iff class TYPE has a virtual destructor. */
4291 bool
4293 {
4294 tree dtor;
4302 }
4304 /* Returns true iff class T has a move constructor. */
4306 bool
4308 {
4309 tree fns;
4312 {
4315 }
4325 }
4327 /* Returns true iff class T has a move assignment operator. */
4329 bool
4331 {
4332 tree fns;
4335 {
4338 }
4346 }
4348 /* Remove all zero-width bit-fields from T. */
4350 static void
4352 {
4357 {
4360 /* We should not be confused by the fact that grokbitfield
4361 temporarily sets the width of the bit field into
4362 DECL_INITIAL (*fieldsp).
4363 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4364 to that width. */
4367 else
4369 }
4370 }
4372 /* Returns TRUE iff we need a cookie when dynamically allocating an
4373 array whose elements have the indicated class TYPE. */
4375 static bool
4377 {
4378 tree fns;
4383 /* If there's a non-trivial destructor, we need a cookie. In order
4384 to iterate through the array calling the destructor for each
4385 element, we'll have to know how many elements there are. */
4389 /* If the usual deallocation function is a two-argument whose second
4390 argument is of type `size_t', then we have to pass the size of
4391 the array to the deallocation function, so we will need to store
4392 a cookie. */
4396 /* If there are no `operator []' members, or the lookup is
4397 ambiguous, then we don't need a cookie. */
4400 /* Loop through all of the functions. */
4402 {
4403 tree fn;
4404 tree second_parm;
4406 /* Select the current function. */
4408 /* See if this function is a one-argument delete function. If
4409 it is, then it will be the usual deallocation function. */
4413 /* Do not consider this function if its second argument is an
4414 ellipsis. */
4417 /* Otherwise, if we have a two-argument function and the second
4418 argument is `size_t', it will be the usual deallocation
4419 function -- unless there is one-argument function, too. */
4423 }
4426 }
4428 /* Check the validity of the bases and members declared in T. Add any
4429 implicitly-generated functions (like copy-constructors and
4430 assignment operators). Compute various flag bits (like
4431 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4432 level: i.e., independently of the ABI in use. */
4434 static void
4436 {
4437 /* Nonzero if the implicitly generated copy constructor should take
4438 a non-const reference argument. */
4440 /* Nonzero if the implicitly generated assignment operator
4441 should take a non-const reference argument. */
4443 tree access_decls;
4446 tree fn;
4448 /* By default, we use const reference arguments and generate default
4449 constructors. */
4453 /* Check all the base-classes. */
4457 /* Check all the method declarations. */
4460 /* Save the initial values of these flags which only indicate whether
4461 or not the class has user-provided functions. As we analyze the
4462 bases and members we can set these flags for other reasons. */
4466 /* Check all the data member declarations. We cannot call
4467 check_field_decls until we have called check_bases check_methods,
4468 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4469 being set appropriately. */
4474 /* A nearly-empty class has to be vptr-containing; a nearly empty
4475 class contains just a vptr. */
4479 /* Do some bookkeeping that will guide the generation of implicitly
4480 declared member functions. */
4483 /* We need to call a constructor for this class if it has a
4484 user-provided constructor, or if the default constructor is going
4485 to initialize the vptr. (This is not an if-and-only-if;
4486 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4487 themselves need constructing.) */
4490 /* [dcl.init.aggr]
4492 An aggregate is an array or a class with no user-provided
4493 constructors ... and no virtual functions.
4495 Again, other conditions for being an aggregate are checked
4496 elsewhere. */
4499 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4500 retain the old definition internally for ABI reasons. */
4509 /* If the class has no user-declared constructor, but does have
4510 non-static const or reference data members that can never be
4511 initialized, issue a warning. */
4513 /* Classes with user-declared constructors are presumed to
4514 initialize these members. */
4516 /* Aggregates can be initialized with brace-enclosed
4517 initializers. */
4519 {
4520 tree field;
4523 {
4524 tree type;
4538 }
4539 }
4541 /* Synthesize any needed methods. */
4543 cant_have_const_ctor,
4544 no_const_asn_ref);
4546 /* Check defaulted declarations here so we have cant_have_const_ctor
4547 and don't need to worry about clones. */
4550 {
4553 {
4554 bool imp_const_p
4560 /* If the function is defaulted outside the class, we just
4561 give the synthesis error. */
4567 }
4569 }
4572 {
4573 /* "The closure type associated with a lambda-expression has a deleted
4574 default constructor and a deleted copy assignment operator." */
4580 /* "This class type is not an aggregate." */
4582 }
4584 /* Create the in-charge and not-in-charge variants of constructors
4585 and destructors. */
4588 /* Process the using-declarations. */
4592 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4595 /* Figure out whether or not we will need a cookie when dynamically
4596 allocating an array of this type. */
4599 }
4601 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4602 accordingly. If a new vfield was created (because T doesn't have a
4603 primary base class), then the newly created field is returned. It
4604 is not added to the TYPE_FIELDS list; it is the caller's
4605 responsibility to do that. Accumulate declared virtual functions
4606 on VIRTUALS_P. */
4608 static tree
4610 {
4611 tree fn;
4613 /* Collect the virtual functions declared in T. */
4617 {
4626 }
4628 /* If we couldn't find an appropriate base class, create a new field
4629 here. Even if there weren't any new virtual functions, we might need a
4630 new virtual function table if we're supposed to include vptrs in
4631 all classes that need them. */
4633 {
4634 /* We build this decl with vtbl_ptr_type_node, which is a
4635 `vtable_entry_type*'. It might seem more precise to use
4636 `vtable_entry_type (*)[N]' where N is the number of virtual
4637 functions. However, that would require the vtable pointer in
4638 base classes to have a different type than the vtable pointer
4639 in derived classes. We could make that happen, but that
4640 still wouldn't solve all the problems. In particular, the
4641 type-based alias analysis code would decide that assignments
4642 to the base class vtable pointer can't alias assignments to
4643 the derived class vtable pointer, since they have different
4644 types. Thus, in a derived class destructor, where the base
4645 class constructor was inlined, we could generate bad code for
4646 setting up the vtable pointer.
4648 Therefore, we use one type for all vtable pointers. We still
4649 use a type-correct type; it's just doesn't indicate the array
4650 bounds. That's better than using `void*' or some such; it's
4651 cleaner, and it let's the alias analysis code know that these
4652 stores cannot alias stores to void*! */
4653 tree field;
4666 /* This class is non-empty. */
4670 }
4673 }
4675 /* Add OFFSET to all base types of BINFO which is a base in the
4676 hierarchy dominated by T.
4678 OFFSET, which is a type offset, is number of bytes. */
4680 static void
4682 {
4684 tree primary_binfo;
4685 tree base_binfo;
4687 /* Update BINFO's offset. */
4692 offset));
4694 /* Find the primary base class. */
4700 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4701 downwards. */
4703 {
4704 /* Don't do the primary base twice. */
4712 }
4713 }
4715 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4716 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4717 empty subobjects of T. */
4719 static void
4721 {
4722 tree vbase;
4731 {
4732 /* In G++ 3.2, we incorrectly rounded the size before laying out
4733 the virtual bases. */
4735 #ifdef STRUCTURE_SIZE_BOUNDARY
4736 /* Packed structures don't need to have minimum size. */
4739 #endif
4743 }
4745 /* Find the last field. The artificial fields created for virtual
4746 bases will go after the last extant field to date. */
4751 /* Go through the virtual bases, allocating space for each virtual
4752 base that is not already a primary base class. These are
4753 allocated in inheritance graph order. */
4755 {
4760 {
4763 /* This virtual base is not a primary base of any class in the
4764 hierarchy, so we have to add space for it. */
4768 /* If the first virtual base might have been placed at a
4769 lower address, had we started from CLASSTYPE_SIZE, rather
4770 than TYPE_SIZE, issue a warning. There can be both false
4771 positives and false negatives from this warning in rare
4772 cases; to deal with all the possibilities would probably
4773 require performing both layout algorithms and comparing
4774 the results which is not particularly tractable. */
4776 && first_vbase
4777 && (tree_int_cst_lt
4782 bitsize_unit_node),
4785 "offset of virtual base %qT is not ABI-compliant and "
4787 basetype);
4790 }
4791 }
4792 }
4794 /* Returns the offset of the byte just past the end of the base class
4795 BINFO. */
4797 static tree
4799 {
4800 tree size;
4805 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4806 allocate some space for it. It cannot have virtual bases, so
4807 TYPE_SIZE_UNIT is fine. */
4809 else
4813 }
4815 /* Returns the offset of the byte just past the end of the base class
4816 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4817 only non-virtual bases are included. */
4819 static tree
4821 {
4824 tree binfo;
4825 tree base_binfo;
4826 tree offset;
4831 {
4841 }
4843 /* G++ 3.2 did not check indirect virtual bases. */
4847 {
4851 }
4854 }
4856 /* Warn about bases of T that are inaccessible because they are
4857 ambiguous. For example:
4859 struct S {};
4860 struct T : public S {};
4861 struct U : public S, public T {};
4863 Here, `(S*) new U' is not allowed because there are two `S'
4864 subobjects of U. */
4866 static void
4868 {
4871 tree basetype;
4872 tree binfo;
4873 tree base_binfo;
4875 /* If there are no repeated bases, nothing can be ambiguous. */
4879 /* Check direct bases. */
4882 {
4888 }
4890 /* Check for ambiguous virtual bases. */
4894 {
4900 }
4901 }
4903 /* Compare two INTEGER_CSTs K1 and K2. */
4905 static int
4907 {
4909 }
4911 /* Increase the size indicated in RLI to account for empty classes
4912 that are "off the end" of the class. */
4914 static void
4916 {
4917 tree eoc;
4918 tree rli_size;
4920 /* It might be the case that we grew the class to allocate a
4921 zero-sized base class. That won't be reflected in RLI, yet,
4922 because we are willing to overlay multiple bases at the same
4923 offset. However, now we need to make sure that RLI is big enough
4924 to reflect the entire class. */
4930 {
4932 /* In version 1 of the ABI, the size of a class that ends with
4933 a bitfield was not rounded up to a whole multiple of a
4934 byte. Because rli_size_unit_so_far returns only the number
4935 of fully allocated bytes, any extra bits were not included
4936 in the size. */
4938 else
4939 /* The size should have been rounded to a whole byte. */
4942 rli->bitpos
4951 }
4952 }
4954 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4955 BINFO_OFFSETs for all of the base-classes. Position the vtable
4956 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4958 static void
4960 {
4961 tree non_static_data_members;
4962 tree field;
4963 tree vptr;
4964 record_layout_info rli;
4965 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4966 types that appear at that offset. */
4967 splay_tree empty_base_offsets;
4968 /* True if the last field layed out was a bit-field. */
4970 /* The location at which the next field should be inserted. */
4972 /* T, as a base class. */
4973 tree base_t;
4975 /* Keep track of the first non-static data member. */
4978 /* Start laying out the record. */
4981 /* Mark all the primary bases in the hierarchy. */
4984 /* Create a pointer to our virtual function table. */
4987 /* The vptr is always the first thing in the class. */
4989 {
4994 }
4995 else
4998 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5003 /* Layout the non-static data members. */
5005 {
5006 tree type;
5007 tree padding;
5009 /* We still pass things that aren't non-static data members to
5010 the back end, in case it wants to do something with them. */
5012 {
5014 /* If the static data member has incomplete type, keep track
5015 of it so that it can be completed later. (The handling
5016 of pending statics in finish_record_layout is
5017 insufficient; consider:
5019 struct S1;
5020 struct S2 { static S1 s1; };
5022 At this point, finish_record_layout will be called, but
5023 S1 is still incomplete.) */
5025 {
5027 /* The visibility of static data members is determined
5028 at their point of declaration, not their point of
5029 definition. */
5031 }
5033 }
5041 /* If this field is a bit-field whose width is greater than its
5042 type, then there are some special rules for allocating
5043 it. */
5046 {
5048 tree integer_type;
5050 /* We must allocate the bits as if suitably aligned for the
5051 longest integer type that fits in this many bits. type
5052 of the field. Then, we are supposed to use the left over
5053 bits as additional padding. */
5062 /* ITK now indicates a type that is too large for the
5063 field. We have to back up by one to find the largest
5064 type that fits. */
5065 do
5066 {
5071 /* Figure out how much additional padding is required. GCC
5072 3.2 always created a padding field, even if it had zero
5073 width. */
5076 {
5078 /* In a union, the padding field must have the full width
5079 of the bit-field; all fields start at offset zero. */
5081 else
5082 {
5085 "ABI-compliant and may change in a future "
5087 t);
5090 }
5091 }
5092 #ifdef PCC_BITFIELD_TYPE_MATTERS
5093 /* An unnamed bitfield does not normally affect the
5094 alignment of the containing class on a target where
5095 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5096 make any exceptions for unnamed bitfields when the
5097 bitfields are longer than their types. Therefore, we
5098 temporarily give the field a name. */
5100 {
5103 }
5104 #endif
5109 empty_base_offsets);
5112 /* Now that layout has been performed, set the size of the
5113 field to the size of its declared type; the rest of the
5114 field is effectively invisible. */
5116 /* We must also reset the DECL_MODE of the field. */
5121 /* Versions of G++ before G++ 3.4 did not reset the
5122 DECL_MODE. */
5124 "the offset of %qD may not be ABI-compliant and may "
5126 }
5127 else
5129 empty_base_offsets);
5131 /* Remember the location of any empty classes in FIELD. */
5135 empty_base_offsets,
5138 /* If a bit-field does not immediately follow another bit-field,
5139 and yet it starts in the middle of a byte, we have failed to
5140 comply with the ABI. */
5143 /* The TREE_NO_WARNING flag gets set by Objective-C when
5144 laying out an Objective-C class. The ObjC ABI differs
5145 from the C++ ABI, and so we do not want a warning
5146 here. */
5148 && !last_field_was_bitfield
5151 bitsize_unit_node)))
5155 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5156 offset of the field. */
5163 "classes to be placed at different locations in a "
5166 /* The middle end uses the type of expressions to determine the
5167 possible range of expression values. In order to optimize
5168 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5169 must be made aware of the width of "i", via its type.
5171 Because C++ does not have integer types of arbitrary width,
5172 we must (for the purposes of the front end) convert from the
5173 type assigned here to the declared type of the bitfield
5174 whenever a bitfield expression is used as an rvalue.
5175 Similarly, when assigning a value to a bitfield, the value
5176 must be converted to the type given the bitfield here. */
5178 {
5183 {
5190 }
5191 }
5193 /* If we needed additional padding after this field, add it
5194 now. */
5196 {
5197 tree padding_field;
5200 FIELD_DECL,
5201 NULL_TREE,
5202 char_type_node);
5209 NULL_TREE,
5210 empty_base_offsets);
5211 }
5214 }
5217 {
5218 /* Make sure that we are on a byte boundary so that the size of
5219 the class without virtual bases will always be a round number
5220 of bytes. */
5223 }
5225 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5226 padding. */
5230 /* Delete all zero-width bit-fields from the list of fields. Now
5231 that the type is laid out they are no longer important. */
5234 /* Create the version of T used for virtual bases. We do not use
5235 make_class_type for this version; this is an artificial type. For
5236 a POD type, we just reuse T. */
5238 {
5241 /* Set the size and alignment for the new type. In G++ 3.2, all
5242 empty classes were considered to have size zero when used as
5243 base classes. */
5245 {
5250 "layout of classes derived from empty class %qT "
5252 t);
5253 }
5254 else
5255 {
5256 tree eoc;
5258 /* If the ABI version is not at least two, and the last
5259 field was a bit-field, RLI may not be on a byte
5260 boundary. In particular, rli_size_unit_so_far might
5261 indicate the last complete byte, while rli_size_so_far
5262 indicates the total number of bits used. Therefore,
5263 rli_size_so_far, rather than rli_size_unit_so_far, is
5264 used to compute TYPE_SIZE_UNIT. */
5272 eoc);
5279 }
5283 /* Copy the fields from T. */
5287 {
5289 FIELD_DECL,
5299 }
5301 /* Record the base version of the type. */
5304 }
5305 else
5308 /* Every empty class contains an empty class. */
5312 /* Set the TYPE_DECL for this type to contain the right
5313 value for DECL_OFFSET, so that we can use it as part
5314 of a COMPONENT_REF for multiple inheritance. */
5317 /* Now fix up any virtual base class types that we left lying
5318 around. We must get these done before we try to lay out the
5319 virtual function table. As a side-effect, this will remove the
5320 base subobject fields. */
5323 /* Make sure that empty classes are reflected in RLI at this
5324 point. */
5327 /* Make sure not to create any structures with zero size. */
5333 /* If this is a non-POD, declaring it packed makes a difference to how it
5334 can be used as a field; don't let finalize_record_size undo it. */
5338 /* Let the back end lay out the type. */
5341 /* Warn about bases that can't be talked about due to ambiguity. */
5344 /* Now that we're done with layout, give the base fields the real types. */
5349 /* Clean up. */
5356 }
5358 /* Determine the "key method" for the class type indicated by TYPE,
5359 and set CLASSTYPE_KEY_METHOD accordingly. */
5361 void
5363 {
5364 tree method;
5367 || processing_template_decl
5372 /* The key method is the first non-pure virtual function that is not
5373 inline at the point of class definition. On some targets the
5374 key function may not be inline; those targets should not call
5375 this function until the end of the translation unit. */
5381 {
5384 }
5387 }
5389 /* Perform processing required when the definition of T (a class type)
5390 is complete. */
5392 void
5394 {
5395 tree x;
5396 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5401 {
5406 }
5408 /* If this type was previously laid out as a forward reference,
5409 make sure we lay it out again. */
5413 /* Make assumptions about the class; we'll reset the flags if
5414 necessary. */
5419 /* Do end-of-class semantic processing: checking the validity of the
5420 bases and members and add implicitly generated methods. */
5423 /* Find the key method. */
5425 {
5426 /* The Itanium C++ ABI permits the key method to be chosen when
5427 the class is defined -- even though the key method so
5428 selected may later turn out to be an inline function. On
5429 some systems (such as ARM Symbian OS) the key method cannot
5430 be determined until the end of the translation unit. On such
5431 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5432 will cause the class to be added to KEYED_CLASSES. Then, in
5433 finish_file we will determine the key method. */
5437 /* If a polymorphic class has no key method, we may emit the vtable
5438 in every translation unit where the class definition appears. */
5441 }
5443 /* Layout the class itself. */
5446 /* We use the base type for trivial assignments, and hence it
5447 needs a mode. */
5452 /* If necessary, create the primary vtable for this class. */
5454 {
5455 /* We must enter these virtuals into the table. */
5459 /* Here we know enough to change the type of our virtual
5460 function table, but we will wait until later this function. */
5462 }
5465 {
5467 tree fn;
5474 /* Add entries for virtual functions introduced by this class. */
5478 /* Set DECL_VINDEX for all functions declared in this class. */
5480 fn;
5482 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5484 {
5488 /* A thunk. We should never be calling this entry directly
5489 from this vtable -- we'd use the entry for the non
5490 thunk base function. */
5494 }
5495 }
5499 /* Complete the rtl for any static member objects of the type we're
5500 working on. */
5507 /* Done with FIELDS...now decide whether to sort these for
5508 faster lookups later.
5510 We use a small number because most searches fail (succeeding
5511 ultimately as the search bores through the inheritance
5512 hierarchy), and we want this failure to occur quickly. */
5516 {
5522 field_decl_cmp);
5524 }
5526 /* Complain if one of the field types requires lower visibility. */
5529 /* Make the rtl for any new vtables we have created, and unmark
5530 the base types we marked. */
5533 /* Build the VTT for T. */
5536 /* This warning does not make sense for Java classes, since they
5537 cannot have destructors. */
5539 {
5540 tree dtor;
5544 if it were virtual, we would have created it by now. */
5545 !dtor
5554 "%q#T has virtual functions and accessible"
5556 }
5563 /* Class layout, assignment of virtual table slots, etc., is now
5564 complete. Give the back end a chance to tweak the visibility of
5565 the class or perform any other required target modifications. */
5572 /* Finish debugging output for this type. */
5574 }
5576 /* When T was built up, the member declarations were added in reverse
5577 order. Rearrange them to declaration order. */
5579 void
5581 {
5582 tree next;
5583 tree prev;
5584 tree x;
5586 /* The following lists are all in reverse order. Put them in
5587 declaration order now. */
5591 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5592 reverse order, so we can't just use nreverse. */
5597 {
5601 }
5603 {
5607 }
5608 }
5610 tree
5612 {
5615 /* Now that we've got all the field declarations, reverse everything
5616 as necessary. */
5621 /* Nadger the current location so that diagnostics point to the start of
5622 the struct, not the end. */
5626 {
5627 tree x;
5633 /* We need to emit an error message if this type was used as a parameter
5634 and it is an abstract type, even if it is a template. We construct
5635 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5636 account and we call complete_vars with this type, which will check
5637 the PARM_DECLS. Note that while the type is being defined,
5638 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5639 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5646 /* Remember current #pragma pack value. */
5648 }
5649 else
5658 else
5665 }
5666 \f
5667 /* Return the dynamic type of INSTANCE, if known.
5668 Used to determine whether the virtual function table is needed
5669 or not.
5671 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5672 of our knowledge of its type. *NONNULL should be initialized
5673 before this function is called. */
5675 static tree
5677 {
5678 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5681 {
5685 else
5689 /* This is a call to a constructor, hence it's never zero. */
5691 {
5695 }
5699 /* This is a call to a constructor, hence it's never zero. */
5701 {
5705 }
5714 /* Propagate nonnull. */
5719 CASE_CONVERT:
5725 {
5726 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5727 with a real object -- given &p->f, p can still be null. */
5729 /* ??? Probably should check DECL_WEAK here. */
5732 }
5736 /* If this component is really a base class reference, then the field
5737 itself isn't definitive. */
5746 {
5750 }
5751 /* fall through... */
5756 {
5760 }
5762 {
5766 /* if we're in a ctor or dtor, we know our type. */
5770 {
5774 }
5775 }
5777 {
5778 /* We only need one hash table because it is always left empty. */
5782 htab_hash_pointer,
5783 htab_eq_pointer,
5786 /* Reference variables should be references to objects. */
5790 /* Enter the INSTANCE in a table to prevent recursion; a
5791 variable's initializer may refer to the variable
5792 itself. */
5796 {
5797 tree type;
5806 }
5807 }
5812 }
5813 #undef RECUR
5814 }
5816 /* Return nonzero if the dynamic type of INSTANCE is known, and
5817 equivalent to the static type. We also handle the case where
5818 INSTANCE is really a pointer. Return negative if this is a
5819 ctor/dtor. There the dynamic type is known, but this might not be
5820 the most derived base of the original object, and hence virtual
5821 bases may not be layed out according to this type.
5823 Used to determine whether the virtual function table is needed
5824 or not.
5826 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5827 of our knowledge of its type. *NONNULL should be initialized
5828 before this function is called. */
5830 int
5832 {
5843 }
5845 \f
5846 void
5848 {
5851 current_class_stack
5859 }
5861 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5863 static void
5865 {
5866 tree type;
5868 /* We are re-entering the same class we just left, so we don't
5869 have to search the whole inheritance matrix to find all the
5870 decls to bind again. Instead, we install the cached
5871 class_shadowed list and walk through it binding names. */
5874 /* Restore IDENTIFIER_TYPE_VALUE. */
5876 type;
5879 }
5881 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5882 appropriate for TYPE.
5884 So that we may avoid calls to lookup_name, we cache the _TYPE
5885 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5887 For multiple inheritance, we perform a two-pass depth-first search
5888 of the type lattice. */
5890 void
5892 {
5893 class_stack_node_t csn;
5897 /* Make sure there is enough room for the new entry on the stack. */
5899 {
5901 current_class_stack
5903 current_class_stack_size);
5904 }
5906 /* Insert a new entry on the class stack. */
5913 current_class_depth++;
5915 /* Now set up the new type. */
5921 /* By default, things in classes are private, while things in
5922 structures or unions are public. */
5924 ? access_private_node
5930 {
5931 /* Forcibly remove any old class remnants. */
5933 }
5939 else
5941 }
5943 /* When we exit a toplevel class scope, we save its binding level so
5944 that we can restore it quickly. Here, we've entered some other
5945 class, so we must invalidate our cache. */
5947 void
5949 {
5951 }
5953 /* Get out of the current class scope. If we were in a class scope
5954 previously, that is the one popped to. */
5956 void
5958 {
5961 current_class_depth--;
5967 }
5969 /* Mark the top of the class stack as hidden. */
5971 void
5973 {
5976 }
5978 /* Mark the top of the class stack as un-hidden. */
5980 void
5982 {
5985 }
5987 /* Returns 1 if the class type currently being defined is either T or
5988 a nested type of T. */
5990 bool
5992 {
6000 /* We start looking from 1 because entry 0 is from global scope,
6001 and has no type. */
6003 {
6004 tree c;
6007 else
6008 {
6012 }
6017 }
6019 }
6021 /* If either current_class_type or one of its enclosing classes are derived
6022 from T, return the appropriate type. Used to determine how we found
6023 something via unqualified lookup. */
6025 tree
6027 {
6030 /* The bases of a dependent type are unknown. */
6041 {
6046 }
6049 }
6051 /* Returns the innermost class type which is not a lambda closure type. */
6053 tree
6055 {
6058 /* We start looking from 1 because entry 0 is from global scope,
6059 and has no type. */
6061 {
6062 tree c;
6065 else
6066 {
6070 }
6075 }
6077 }
6079 /* When entering a class scope, all enclosing class scopes' names with
6080 static meaning (static variables, static functions, types and
6081 enumerators) have to be visible. This recursive function calls
6082 pushclass for all enclosing class contexts until global or a local
6083 scope is reached. TYPE is the enclosed class. */
6085 void
6087 {
6088 /* A namespace might be passed in error cases, like A::B:C. */
6096 }
6098 /* Undoes a push_nested_class call. */
6100 void
6102 {
6108 }
6110 /* Returns the number of extern "LANG" blocks we are nested within. */
6112 int
6114 {
6116 }
6118 /* Set global variables CURRENT_LANG_NAME to appropriate value
6119 so that behavior of name-mangling machinery is correct. */
6121 void
6123 {
6127 {
6129 }
6131 {
6133 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6134 (See record_builtin_java_type in decl.c.) However, that causes
6135 incorrect debug entries if these types are actually used.
6136 So we re-enable debug output after extern "Java". */
6145 }
6147 {
6149 }
6150 else
6152 }
6154 /* Get out of the current language scope. */
6156 void
6158 {
6160 }
6161 \f
6162 /* Type instantiation routines. */
6164 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6165 matches the TARGET_TYPE. If there is no satisfactory match, return
6166 error_mark_node, and issue an error & warning messages under
6167 control of FLAGS. Permit pointers to member function if FLAGS
6168 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6169 a template-id, and EXPLICIT_TARGS are the explicitly provided
6170 template arguments.
6172 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6173 is the base path used to reference those member functions. If
6174 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6175 resolved to a member function, access checks will be performed and
6176 errors issued if appropriate. */
6178 static tree
6180 tree overload,
6181 tsubst_flags_t flags,
6183 tree explicit_targs,
6184 tree access_path)
6185 {
6186 /* Here's what the standard says:
6188 [over.over]
6190 If the name is a function template, template argument deduction
6191 is done, and if the argument deduction succeeds, the deduced
6192 arguments are used to generate a single template function, which
6193 is added to the set of overloaded functions considered.
6195 Non-member functions and static member functions match targets of
6196 type "pointer-to-function" or "reference-to-function." Nonstatic
6197 member functions match targets of type "pointer-to-member
6198 function;" the function type of the pointer to member is used to
6199 select the member function from the set of overloaded member
6200 functions. If a nonstatic member function is selected, the
6201 reference to the overloaded function name is required to have the
6202 form of a pointer to member as described in 5.3.1.
6204 If more than one function is selected, any template functions in
6205 the set are eliminated if the set also contains a non-template
6206 function, and any given template function is eliminated if the
6207 set contains a second template function that is more specialized
6208 than the first according to the partial ordering rules 14.5.5.2.
6209 After such eliminations, if any, there shall remain exactly one
6210 selected function. */
6213 /* We store the matches in a TREE_LIST rooted here. The functions
6214 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6215 interoperability with most_specialized_instantiation. */
6217 tree fn;
6218 tree target_fn_type;
6220 /* By the time we get here, we should be seeing only real
6221 pointer-to-member types, not the internal POINTER_TYPE to
6222 METHOD_TYPE representation. */
6228 /* Check that the TARGET_TYPE is reasonable. */
6232 /* This is OK, too. */
6235 /* This is OK, too. This comes from a conversion to reference
6236 type. */
6238 else
6239 {
6245 }
6247 /* Non-member functions and static member functions match targets of type
6248 "pointer-to-function" or "reference-to-function." Nonstatic member
6249 functions match targets of type "pointer-to-member-function;" the
6250 function type of the pointer to member is used to select the member
6251 function from the set of overloaded member functions.
6253 So figure out the FUNCTION_TYPE that we want to match against. */
6256 /* If we can find a non-template function that matches, we can just
6257 use it. There's no point in generating template instantiations
6258 if we're just going to throw them out anyhow. But, of course, we
6259 can only do this when we don't *need* a template function. */
6261 {
6262 tree fns;
6265 {
6269 /* We're not looking for templates just yet. */
6274 /* We're looking for a non-static member, and this isn't
6275 one, or vice versa. */
6278 /* Ignore functions which haven't been explicitly
6279 declared. */
6283 /* See if there's a match. */
6286 }
6287 }
6289 /* Now, if we've already got a match (or matches), there's no need
6290 to proceed to the template functions. But, if we don't have a
6291 match we need to look at them, too. */
6293 {
6294 tree target_arg_types;
6295 tree target_ret_type;
6296 tree fns;
6299 tree arg;
6313 {
6315 tree instantiation;
6316 tree targs;
6319 /* We're only looking for templates. */
6324 /* We're not looking for a non-static member, and this is
6325 one, or vice versa. */
6328 /* Try to do argument deduction. */
6332 LOOKUP_NORMAL))
6333 /* Argument deduction failed. */
6336 /* Instantiate the template. */
6339 /* Instantiation failed. */
6342 /* See if there's a match. */
6345 }
6347 /* Now, remove all but the most specialized of the matches. */
6349 {
6354 NULL_TREE,
6355 NULL_TREE);
6356 }
6357 }
6359 /* Now we should have exactly one function in MATCHES. */
6361 {
6362 /* There were *no* matches. */
6364 {
6367 target_type);
6369 /* print_candidates expects a chain with the functions in
6370 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6371 so why be clever?). */
6374 matches);
6377 }
6379 }
6381 {
6382 /* There were too many matches. First check if they're all
6383 the same function. */
6384 tree match;
6392 {
6394 {
6397 target_type);
6399 /* Since print_candidates expects the functions in the
6400 TREE_VALUE slot, we flip them here. */
6405 }
6408 }
6409 }
6411 /* Good, exactly one match. Now, convert it to the correct type. */
6416 {
6424 {
6427 }
6428 }
6430 /* If we're doing overload resolution purely for the purpose of
6431 determining conversion sequences, we should not consider the
6432 function used. If this conversion sequence is selected, the
6433 function will be marked as used at this point. */
6435 {
6436 /* Make =delete work with SFINAE. */
6441 }
6443 /* We could not check access to member functions when this
6444 expression was originally created since we did not know at that
6445 time to which function the expression referred. */
6448 {
6451 }
6455 else
6456 {
6457 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6458 will mark the function as addressed, but here we must do it
6459 explicitly. */
6463 }
6464 }
6466 /* This function will instantiate the type of the expression given in
6467 RHS to match the type of LHSTYPE. If errors exist, then return
6468 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6469 we complain on errors. If we are not complaining, never modify rhs,
6470 as overload resolution wants to try many possible instantiations, in
6471 the hope that at least one will work.
6473 For non-recursive calls, LHSTYPE should be a function, pointer to
6474 function, or a pointer to member function. */
6476 tree
6478 {
6485 {
6489 }
6492 {
6498 /* Microsoft allows `A::f' to be resolved to a
6499 pointer-to-member. */
6500 ;
6501 else
6502 {
6507 }
6508 }
6511 {
6514 }
6516 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6517 deduce any type information. */
6519 {
6523 }
6525 /* There only a few kinds of expressions that may have a type
6526 dependent on overload resolution. */
6532 /* This should really only be used when attempting to distinguish
6533 what sort of a pointer to function we have. For now, any
6534 arithmetic operation which is not supported on pointers
6535 is rejected as an error. */
6538 {
6540 {
6546 /* Do not lose object's side effects. */
6550 }
6557 /* This can happen if we are forming a pointer-to-member for a
6558 member template. */
6561 /* Fall through. */
6564 {
6568 return
6572 }
6576 return
6580 access_path);
6583 {
6588 }
6595 }
6597 }
6598 \f
6599 /* Return the name of the virtual function pointer field
6600 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6601 this may have to look back through base types to find the
6602 ultimate field name. (For single inheritance, these could
6603 all be the same name. Who knows for multiple inheritance). */
6605 static tree
6607 {
6614 {
6620 }
6628 }
6630 void
6632 {
6633 #ifdef GATHER_STATISTICS
6637 {
6642 }
6643 #endif
6644 }
6646 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6647 according to [class]:
6648 The class-name is also inserted
6649 into the scope of the class itself. For purposes of access checking,
6650 the inserted class name is treated as if it were a public member name. */
6652 void
6654 {
6657 tree saved_cas;
6672 }
6674 /* Returns 1 if TYPE contains only padding bytes. */
6676 int
6678 {
6685 /* In G++ 3.2, whether or not a class was empty was determined by
6686 looking at its size. */
6689 else
6691 }
6693 /* Returns true if TYPE contains an empty class. */
6695 static bool
6697 {
6701 {
6702 tree field;
6703 tree binfo;
6704 tree base_binfo;
6716 }
6720 }
6722 /* Returns true if TYPE contains no actual data, just various
6723 possible combinations of empty classes. */
6725 bool
6727 {
6731 {
6732 tree field;
6733 tree binfo;
6734 tree base_binfo;
6747 }
6751 }
6753 /* Note that NAME was looked up while the current class was being
6754 defined and that the result of that lookup was DECL. */
6756 void
6758 {
6759 splay_tree names_used;
6761 /* If we're not defining a class, there's nothing to do. */
6767 /* If there's already a binding for this NAME, then we don't have
6768 anything to worry about. */
6781 }
6783 /* Note that NAME was declared (as DECL) in the current class. Check
6784 to see that the declaration is valid. */
6786 void
6788 {
6789 splay_tree names_used;
6790 splay_tree_node n;
6792 /* Look to see if we ever used this name. */
6793 names_used
6800 {
6801 /* [basic.scope.class]
6803 A name N used in a class S shall refer to the same declaration
6804 in its context and when re-evaluated in the completed scope of
6805 S. */
6809 }
6810 }
6812 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6813 Secondary vtables are merged with primary vtables; this function
6814 will return the VAR_DECL for the primary vtable. */
6816 tree
6818 {
6819 tree decl;
6823 {
6826 }
6830 }
6833 /* Returns the binfo for the primary base of BINFO. If the resulting
6834 BINFO is a virtual base, and it is inherited elsewhere in the
6835 hierarchy, then the returned binfo might not be the primary base of
6836 BINFO in the complete object. Check BINFO_PRIMARY_P or
6837 BINFO_LOST_PRIMARY_P to be sure. */
6839 static tree
6841 {
6842 tree primary_base;
6849 }
6851 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6853 static int
6855 {
6859 }
6861 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6862 INDENT should be zero when called from the top level; it is
6863 incremented recursively. IGO indicates the next expected BINFO in
6864 inheritance graph ordering. */
6866 static tree
6869 tree binfo,
6870 tree igo,
6872 {
6874 tree base_binfo;
6882 {
6885 }
6900 {
6904 TFF_PLAIN_IDENTIFIER),
6906 }
6908 {
6911 }
6916 {
6920 {
6924 TFF_PLAIN_IDENTIFIER));
6925 }
6927 {
6931 TFF_PLAIN_IDENTIFIER));
6932 }
6934 {
6938 TFF_PLAIN_IDENTIFIER));
6939 }
6941 {
6945 TFF_PLAIN_IDENTIFIER));
6946 }
6950 }
6956 }
6958 /* Dump the BINFO hierarchy for T. */
6960 static void
6962 {
6974 }
6976 /* Debug interface to hierarchy dumping. */
6978 void
6980 {
6982 }
6984 static void
6986 {
6991 {
6994 }
6995 }
6997 static void
6999 {
7000 tree value;
7002 HOST_WIDE_INT elt;
7010 TFF_PLAIN_IDENTIFIER));
7017 }
7019 static void
7021 {
7029 {
7036 {
7040 }
7044 }
7047 }
7049 static void
7051 {
7059 {
7064 }
7067 }
7069 /* Dump a function or thunk and its thunkees. */
7071 static void
7073 {
7076 tree thunks;
7084 {
7094 else
7100 }
7104 }
7106 /* Dump the thunks for FN. */
7108 void
7110 {
7112 }
7114 /* Virtual function table initialization. */
7116 /* Create all the necessary vtables for T and its base classes. */
7118 static void
7120 {
7121 tree vbase;
7125 /* We lay out the primary and secondary vtables in one contiguous
7126 vtable. The primary vtable is first, followed by the non-virtual
7127 secondary vtables in inheritance graph order. */
7131 /* Then come the virtual bases, also in inheritance graph order. */
7133 {
7137 }
7141 }
7143 /* Initialize the vtable for BINFO with the INITS. */
7145 static void
7147 {
7148 tree decl;
7154 }
7156 /* Build the VTT (virtual table table) for T.
7157 A class requires a VTT if it has virtual bases.
7159 This holds
7160 1 - primary virtual pointer for complete object T
7161 2 - secondary VTTs for each direct non-virtual base of T which requires a
7162 VTT
7163 3 - secondary virtual pointers for each direct or indirect base of T which
7164 has virtual bases or is reachable via a virtual path from T.
7165 4 - secondary VTTs for each direct or indirect virtual base of T.
7167 Secondary VTTs look like complete object VTTs without part 4. */
7169 static void
7171 {
7172 tree type;
7173 tree vtt;
7174 tree index;
7177 /* Build up the initializers for the VTT. */
7182 /* If we didn't need a VTT, we're done. */
7186 /* Figure out the type of the VTT. */
7190 /* Now, build the VTT object itself. */
7193 /* Add the VTT to the vtables list. */
7198 }
7200 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7201 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7202 and CHAIN the vtable pointer for this binfo after construction is
7203 complete. VALUE can also be another BINFO, in which case we recurse. */
7205 static tree
7207 {
7208 tree vt;
7211 {
7217 else
7219 }
7222 }
7224 /* Data for secondary VTT initialization. */
7226 {
7227 /* Is this the primary VTT? */
7230 /* Current index into the VTT. */
7231 tree index;
7233 /* Vector of initializers built up. */
7236 /* The type being constructed by this secondary VTT. */
7237 tree type_being_constructed;
7240 /* Recursively build the VTT-initializer for BINFO (which is in the
7241 hierarchy dominated by T). INITS points to the end of the initializer
7242 list to date. INDEX is the VTT index where the next element will be
7243 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7244 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7245 for virtual bases of T. When it is not so, we build the constructor
7246 vtables for the BINFO-in-T variant. */
7248 static void
7250 {
7252 tree b;
7253 tree init;
7254 secondary_vptr_vtt_init_data data;
7257 /* We only need VTTs for subobjects with virtual bases. */
7261 /* We need to use a construction vtable if this is not the primary
7262 VTT. */
7264 {
7267 /* Record the offset in the VTT where this sub-VTT can be found. */
7269 }
7271 /* Add the address of the primary vtable for the complete object. */
7275 {
7278 }
7281 /* Recursively add the secondary VTTs for non-virtual bases. */
7286 /* Add secondary virtual pointers for all subobjects of BINFO with
7287 either virtual bases or reachable along a virtual path, except
7288 subobjects that are non-virtual primary bases. */
7298 /* data.inits might have grown as we added secondary virtual pointers.
7299 Make sure our caller knows about the new vector. */
7303 /* Add the secondary VTTs for virtual bases in inheritance graph
7304 order. */
7306 {
7311 }
7312 else
7313 /* Remove the ctor vtables we created. */
7315 }
7317 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7318 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7320 static tree
7322 {
7325 /* We don't care about bases that don't have vtables. */
7329 /* We're only interested in proper subobjects of the type being
7330 constructed. */
7334 /* We're only interested in bases with virtual bases or reachable
7335 via a virtual path from the type being constructed. */
7340 /* We're not interested in non-virtual primary bases. */
7344 /* Record the index where this secondary vptr can be found. */
7346 {
7351 {
7352 /* It's a primary virtual base, and this is not a
7353 construction vtable. Find the base this is primary of in
7354 the inheritance graph, and use that base's vtable
7355 now. */
7358 }
7359 }
7361 /* Add the initializer for the secondary vptr itself. */
7364 /* Advance the vtt index. */
7369 }
7371 /* Called from build_vtt_inits via dfs_walk. After building
7372 constructor vtables and generating the sub-vtt from them, we need
7373 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7374 binfo of the base whose sub vtt was generated. */
7376 static tree
7378 {
7382 /* If this class has no vtable, none of its bases do. */
7386 /* This might be a primary base, so have no vtable in this
7387 hierarchy. */
7390 /* If we scribbled the construction vtable vptr into BINFO, clear it
7391 out now. */
7397 }
7399 /* Build the construction vtable group for BINFO which is in the
7400 hierarchy dominated by T. */
7402 static void
7404 {
7405 tree type;
7406 tree vtbl;
7407 tree id;
7408 tree vbase;
7411 /* See if we've already created this construction vtable group. */
7417 /* Build a version of VTBL (with the wrong type) for use in
7418 constructing the addresses of secondary vtables in the
7419 construction vtable group. */
7427 /* Add the vtables for each of our virtual bases using the vbase in T
7428 binfo. */
7430 vbase;
7432 {
7433 tree b;
7440 }
7442 /* Figure out the type of the construction vtable. */
7450 /* Initialize the construction vtable. */
7454 }
7456 /* Add the vtbl initializers for BINFO (and its bases other than
7457 non-virtual primaries) to the list of INITS. BINFO is in the
7458 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7459 the constructor the vtbl inits should be accumulated for. (If this
7460 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7461 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7462 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7463 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7464 but are not necessarily the same in terms of layout. */
7466 static void
7468 tree orig_binfo,
7469 tree rtti_binfo,
7470 tree vtbl,
7471 tree t,
7473 {
7475 tree base_binfo;
7480 /* If it doesn't have a vptr, we don't do anything. */
7484 /* If we're building a construction vtable, we're not interested in
7485 subobjects that don't require construction vtables. */
7491 /* Build the initializers for the BINFO-in-T vtable. */
7494 /* Walk the BINFO and its bases. We walk in preorder so that as we
7495 initialize each vtable we can figure out at what offset the
7496 secondary vtable lies from the primary vtable. We can't use
7497 dfs_walk here because we need to iterate through bases of BINFO
7498 and RTTI_BINFO simultaneously. */
7500 {
7501 /* Skip virtual bases. */
7507 inits);
7508 }
7509 }
7511 /* Called from accumulate_vtbl_inits. Adds the initializers for the
7512 BINFO vtable to L. */
7514 static void
7516 tree orig_binfo,
7517 tree rtti_binfo,
7518 tree orig_vtbl,
7519 tree t,
7521 {
7528 {
7529 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7530 primary virtual base. If it is not the same primary in
7531 the hierarchy of T, we'll need to generate a ctor vtable
7532 for it, to place at its location in T. If it is the same
7533 primary, we still need a VTT entry for the vtable, but it
7534 should point to the ctor vtable for the base it is a
7535 primary for within the sub-hierarchy of RTTI_BINFO.
7537 There are three possible cases:
7539 1) We are in the same place.
7540 2) We are a primary base within a lost primary virtual base of
7541 RTTI_BINFO.
7542 3) We are primary to something not a base of RTTI_BINFO. */
7544 tree b;
7547 /* First, look through the bases we are primary to for RTTI_BINFO
7548 or a virtual base. */
7551 {
7556 }
7557 /* If we run out of primary links, keep looking down our
7558 inheritance chain; we might be an indirect primary. */
7562 found:
7564 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7565 base B and it is a base of RTTI_BINFO, this is case 2. In
7566 either case, we share our vtable with LAST, i.e. the
7567 derived-most base within B of which we are a primary. */
7570 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7571 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7572 binfo_ctor_vtable after everything's been set up. */
7575 /* Otherwise, this is case 3 and we get our own. */
7576 }
7583 {
7584 tree index;
7587 /* Add the initializer for this vtable. */
7591 /* Figure out the position to which the VPTR should point. */
7598 index);
7600 }
7603 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7604 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7605 straighten this out. */
7608 /* Throw away any unneeded intializers. */
7610 else
7611 /* For an ordinary vtable, set BINFO_VTABLE. */
7613 }
7617 /* Construct the initializer for BINFO's virtual function table. BINFO
7618 is part of the hierarchy dominated by T. If we're building a
7619 construction vtable, the ORIG_BINFO is the binfo we should use to
7620 find the actual function pointers to put in the vtable - but they
7621 can be overridden on the path to most-derived in the graph that
7622 ORIG_BINFO belongs. Otherwise,
7623 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7624 BINFO that should be indicated by the RTTI information in the
7625 vtable; it will be a base class of T, rather than T itself, if we
7626 are building a construction vtable.
7628 The value returned is a TREE_LIST suitable for wrapping in a
7629 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7630 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7631 number of non-function entries in the vtable.
7633 It might seem that this function should never be called with a
7634 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7635 base is always subsumed by a derived class vtable. However, when
7636 we are building construction vtables, we do build vtables for
7637 primary bases; we need these while the primary base is being
7638 constructed. */
7640 static void
7642 tree orig_binfo,
7643 tree t,
7644 tree rtti_binfo,
7647 {
7649 vtbl_init_data vid;
7651 tree vbinfo;
7655 /* Initialize VID. */
7663 /* The first vbase or vcall offset is at index -3 in the vtable. */
7666 /* Add entries to the vtable for RTTI. */
7669 /* Create an array for keeping track of the functions we've
7670 processed. When we see multiple functions with the same
7671 signature, we share the vcall offsets. */
7673 /* Add the vcall and vbase offset entries. */
7676 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7677 build_vbase_offset_vtbl_entries. */
7682 /* If the target requires padding between data entries, add that now. */
7684 {
7690 /* Move data entries into their new positions and add padding
7691 after the new positions. Iterate backwards so we don't
7692 overwrite entries that we would need to process later. */
7695 ix--)
7696 {
7704 {
7709 null_pointer_node);
7710 }
7711 }
7712 }
7717 /* The initializers for virtual functions were built up in reverse
7718 order. Straighten them out and add them to the running list in one
7719 step. */
7729 /* Go through all the ordinary virtual functions, building up
7730 initializers. */
7732 {
7733 tree delta;
7734 tree vcall_index;
7741 {
7745 {
7748 }
7750 }
7752 /* If the only definition of this function signature along our
7753 primary base chain is from a lost primary, this vtable slot will
7754 never be used, so just zero it out. This is important to avoid
7755 requiring extra thunks which cannot be generated with the function.
7757 We first check this in update_vtable_entry_for_fn, so we handle
7758 restored primary bases properly; we also need to do it here so we
7759 zero out unused slots in ctor vtables, rather than filling them
7760 with erroneous values (though harmless, apart from relocation
7761 costs). */
7763 {
7764 /* We found a defn before a lost primary; go ahead as normal. */
7768 /* The nearest definition is from a lost primary; clear the
7769 slot. */
7771 {
7774 }
7775 }
7778 {
7779 /* Pull the offset for `this', and the function to call, out of
7780 the list. */
7787 /* You can't call an abstract virtual function; it's abstract.
7788 So, we replace these functions with __pure_virtual. */
7790 {
7795 }
7796 else
7797 {
7799 {
7803 }
7804 /* Take the address of the function, considering it to be of an
7805 appropriate generic type. */
7807 }
7808 }
7810 /* And add it to the chain of initializers. */
7812 {
7817 else
7819 {
7826 }
7827 }
7828 else
7830 }
7831 }
7833 /* Adds to vid->inits the initializers for the vbase and vcall
7834 offsets in BINFO, which is in the hierarchy dominated by T. */
7836 static void
7838 {
7839 tree b;
7841 /* If this is a derived class, we must first create entries
7842 corresponding to the primary base class. */
7847 /* Add the vbase entries for this base. */
7849 /* Add the vcall entries for this base. */
7851 }
7853 /* Returns the initializers for the vbase offset entries in the vtable
7854 for BINFO (which is part of the class hierarchy dominated by T), in
7855 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7856 where the next vbase offset will go. */
7858 static void
7860 {
7861 tree vbase;
7862 tree t;
7863 tree non_primary_binfo;
7865 /* If there are no virtual baseclasses, then there is nothing to
7866 do. */
7872 /* We might be a primary base class. Go up the inheritance hierarchy
7873 until we find the most derived class of which we are a primary base:
7874 it is the offset of that which we need to use. */
7877 {
7878 tree b;
7880 /* If we have reached a virtual base, then it must be a primary
7881 base (possibly multi-level) of vid->binfo, or we wouldn't
7882 have called build_vcall_and_vbase_vtbl_entries for it. But it
7883 might be a lost primary, so just skip down to vid->binfo. */
7885 {
7888 }
7894 }
7896 /* Go through the virtual bases, adding the offsets. */
7898 vbase;
7900 {
7901 tree b;
7902 tree delta;
7907 /* Find the instance of this virtual base in the complete
7908 object. */
7911 /* If we've already got an offset for this virtual base, we
7912 don't need another one. */
7917 /* Figure out where we can find this vbase offset. */
7926 /* The vbase offset had better be the same. */
7929 /* The next vbase will come at a more negative offset. */
7933 /* The initializer is the delta from BINFO to this virtual base.
7934 The vbase offsets go in reverse inheritance-graph order, and
7935 we are walking in inheritance graph order so these end up in
7936 the right order. */
7943 }
7944 }
7946 /* Adds the initializers for the vcall offset entries in the vtable
7947 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7948 to VID->INITS. */
7950 static void
7952 {
7953 /* We only need these entries if this base is a virtual base. We
7954 compute the indices -- but do not add to the vtable -- when
7955 building the main vtable for a class. */
7958 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7959 correspond to VID->DERIVED), we are building a primary
7960 construction virtual table. Since this is a primary
7961 virtual table, we do not need the vcall offsets for
7962 BINFO. */
7964 {
7965 /* We need a vcall offset for each of the virtual functions in this
7966 vtable. For example:
7968 class A { virtual void f (); };
7969 class B1 : virtual public A { virtual void f (); };
7970 class B2 : virtual public A { virtual void f (); };
7971 class C: public B1, public B2 { virtual void f (); };
7973 A C object has a primary base of B1, which has a primary base of A. A
7974 C also has a secondary base of B2, which no longer has a primary base
7975 of A. So the B2-in-C construction vtable needs a secondary vtable for
7976 A, which will adjust the A* to a B2* to call f. We have no way of
7977 knowing what (or even whether) this offset will be when we define B2,
7978 so we store this "vcall offset" in the A sub-vtable and look it up in
7979 a "virtual thunk" for B2::f.
7981 We need entries for all the functions in our primary vtable and
7982 in our non-virtual bases' secondary vtables. */
7984 /* If we are just computing the vcall indices -- but do not need
7985 the actual entries -- not that. */
7988 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7990 }
7991 }
7993 /* Build vcall offsets, starting with those for BINFO. */
7995 static void
7997 {
7999 tree primary_binfo;
8000 tree base_binfo;
8002 /* Don't walk into virtual bases -- except, of course, for the
8003 virtual base for which we are building vcall offsets. Any
8004 primary virtual base will have already had its offsets generated
8005 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8009 /* If BINFO has a primary base, process it first. */
8014 /* Add BINFO itself to the list. */
8017 /* Scan the non-primary bases of BINFO. */
8021 }
8023 /* Called from build_vcall_offset_vtbl_entries_r. */
8025 static void
8027 {
8028 /* Make entries for the rest of the virtuals. */
8030 {
8031 tree orig_fn;
8033 /* The ABI requires that the methods be processed in declaration
8034 order. G++ 3.2 used the order in the vtable. */
8036 orig_fn;
8040 }
8041 else
8042 {
8043 tree derived_virtuals;
8044 tree base_virtuals;
8045 tree orig_virtuals;
8046 /* If BINFO is a primary base, the most derived class which has
8047 BINFO as a primary base; otherwise, just BINFO. */
8048 tree non_primary_binfo;
8050 /* We might be a primary base class. Go up the inheritance hierarchy
8051 until we find the most derived class of which we are a primary base:
8052 it is the BINFO_VIRTUALS there that we need to consider. */
8055 {
8056 tree b;
8058 /* If we have reached a virtual base, then it must be vid->vbase,
8059 because we ignore other virtual bases in
8060 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8061 base (possibly multi-level) of vid->binfo, or we wouldn't
8062 have called build_vcall_and_vbase_vtbl_entries for it. But it
8063 might be a lost primary, so just skip down to vid->binfo. */
8065 {
8069 }
8075 }
8078 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8079 where rtti_binfo is the most derived type. */
8080 non_primary_binfo
8086 base_virtuals;
8090 {
8091 tree orig_fn;
8093 /* Find the declaration that originally caused this function to
8094 be present in BINFO_TYPE (binfo). */
8097 /* When processing BINFO, we only want to generate vcall slots for
8098 function slots introduced in BINFO. So don't try to generate
8099 one if the function isn't even defined in BINFO. */
8104 }
8105 }
8106 }
8108 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8110 static void
8112 {
8114 tree vcall_offset;
8115 tree derived_entry;
8117 /* If there is already an entry for a function with the same
8118 signature as FN, then we do not need a second vcall offset.
8119 Check the list of functions already present in the derived
8120 class vtable. */
8122 {
8124 /* We only use one vcall offset for virtual destructors,
8125 even though there are two virtual table entries. */
8129 }
8131 /* If we are building these vcall offsets as part of building
8132 the vtable for the most derived class, remember the vcall
8133 offset. */
8135 {
8138 NULL);
8141 }
8143 /* The next vcall offset will be found at a more negative
8144 offset. */
8148 /* Keep track of this function. */
8152 {
8153 tree base;
8154 tree fn;
8156 /* Find the overriding function. */
8160 integer_zero_node);
8161 else
8162 {
8165 /* The vbase we're working on is a primary base of
8166 vid->binfo. But it might be a lost primary, so its
8167 BINFO_OFFSET might be wrong, so we just use the
8168 BINFO_OFFSET from vid->binfo. */
8174 vcall_offset);
8175 }
8176 /* Add the initializer to the vtable. */
8178 }
8179 }
8181 /* Return vtbl initializers for the RTTI entries corresponding to the
8182 BINFO's vtable. The RTTI entries should indicate the object given
8183 by VID->rtti_binfo. */
8185 static void
8187 {
8188 tree b;
8189 tree t;
8190 tree offset;
8191 tree decl;
8192 tree init;
8196 /* To find the complete object, we will first convert to our most
8197 primary base, and then add the offset in the vtbl to that value. */
8201 {
8202 tree primary_base;
8208 }
8212 /* The second entry is the address of the typeinfo object. */
8215 else
8218 /* Convert the declaration to a type that can be stored in the
8219 vtable. */
8223 /* Add the offset-to-top entry. It comes earlier in the vtable than
8224 the typeinfo entry. Convert the offset to look like a
8225 function pointer, so that we can put it in the vtable. */
8228 }
8230 /* Fold a OBJ_TYPE_REF expression to the address of a function.
8231 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
8233 tree
8235 {
8239 tree fndecl;
8242 {
8243 i += (TARGET_VTABLE_USES_DESCRIPTORS
8246 }
8250 #ifdef ENABLE_CHECKING
8253 #endif
8258 }