| blob | 88c920ac0e9769f9d577a57823245d34bfff9275 |
1 /* Process declarations and variables for C++ compiler.
2 Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4 Hacked by Michael Tiemann (tiemann@cygnus.com)
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
11 any later version.
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to
20 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
24 /* Process declarations and symbol lookup for C++ front end.
25 Also constructs types; the standard scalar types at initialization,
26 and structure, union, array and enum types when they are declared. */
28 /* ??? not all decl nodes are given the most useful possible
29 line numbers. For example, the CONST_DECLs for enum values. */
57 /* This structure contains information about the initializations
58 and/or destructions required for a particular priority level. */
60 /* Nonzero if there have been any initializations at this priority
61 throughout the translation unit. */
63 /* Nonzero if there have been any destructions at this priority
64 throughout the translation unit. */
86 /* A list of static class variables. This is needed, because a
87 static class variable can be declared inside the class without
88 an initializer, and then initialized, statically, outside the class. */
91 /* A list of functions which were declared inline, but which we
92 may need to emit outline anyway. */
95 /* Nonzero if we're done parsing and into end-of-file activities. */
99 /* Functions called along with real static constructors and destructors. */
101 tree static_ctors;
102 tree static_dtors;
104 \f
105 /* Incorporate `const' and `volatile' qualifiers for member functions.
106 FUNCTION is a TYPE_DECL or a FUNCTION_DECL.
107 QUALS is a list of qualifiers. Returns any explicit
108 top-level qualifiers of the method's this pointer, anything other than
109 TYPE_UNQUALIFIED will be an extension. */
111 int
113 {
123 {
126 }
138 }
140 /* Build a PARM_DECL with NAME and TYPE, and set DECL_ARG_TYPE
141 appropriately. */
143 tree
145 {
147 /* DECL_ARG_TYPE is only used by the back end and the back end never
148 sees templates. */
152 }
154 /* Returns a PARM_DECL for a parameter of the indicated TYPE, with the
155 indicated NAME. */
157 static tree
159 {
162 /* All our artificial parms are implicitly `const'; they cannot be
163 assigned to. */
166 }
168 /* Constructors for types with virtual baseclasses need an "in-charge" flag
169 saying whether this constructor is responsible for initialization of
170 virtual baseclasses or not. All destructors also need this "in-charge"
171 flag, which additionally determines whether or not the destructor should
172 free the memory for the object.
174 This function adds the "in-charge" flag to member function FN if
175 appropriate. It is called from grokclassfn and tsubst.
176 FN must be either a constructor or destructor.
178 The in-charge flag follows the 'this' parameter, and is followed by the
179 VTT parm (if any), then the user-written parms. */
181 void
183 {
186 /* If we've already add the in-charge parameter don't do it again. */
190 /* When processing templates we can't know, in general, whether or
191 not we're going to have virtual baseclasses. */
195 /* We don't need an in-charge parameter for constructors that don't
196 have virtual bases. */
207 /* If this is a subobject constructor or destructor, our caller will
208 pass us a pointer to our VTT. */
210 {
213 /* First add it to DECL_ARGUMENTS between 'this' and the real args... */
217 /* ...and then to TYPE_ARG_TYPES. */
221 }
223 /* Then add the in-charge parm (before the VTT parm). */
229 /* Insert our new parameter(s) into the list. */
232 /* And rebuild the function type. */
234 arg_types);
240 /* Now we've got the in-charge parameter. */
242 }
244 /* Classes overload their constituent function names automatically.
245 When a function name is declared in a record structure,
246 its name is changed to it overloaded name. Since names for
247 constructors and destructors can conflict, we place a leading
248 '$' for destructors.
250 CNAME is the name of the class we are grokking for.
252 FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'.
254 FLAGS contains bits saying what's special about today's
255 arguments. 1 == DESTRUCTOR. 2 == OPERATOR.
257 If FUNCTION is a destructor, then we must add the `auto-delete' field
258 as a second parameter. There is some hair associated with the fact
259 that we must "declare" this variable in the manner consistent with the
260 way the rest of the arguments were declared.
262 QUALS are the qualifiers for the this pointer. */
264 void
266 cp_cv_quals quals)
267 {
271 /* Even within an `extern "C"' block, members get C++ linkage. See
272 [dcl.link] for details. */
276 {
280 }
286 {
287 /* Must add the class instance variable up front. */
288 /* Right now we just make this a pointer. But later
289 we may wish to make it special. */
291 tree qual_type;
292 tree parm;
294 /* The `this' parameter is implicitly `const'; it cannot be
295 assigned to. */
302 }
311 }
313 /* Create an ARRAY_REF, checking for the user doing things backwards
314 along the way. */
316 tree
318 {
319 tree type;
320 tree expr;
328 {
335 }
341 /* If they have an `operator[]', use that. */
346 else
347 {
350 /* Otherwise, create an ARRAY_REF for a pointer or array type.
351 It is a little-known fact that, if `a' is an array and `i' is
352 an int, you can write `i[a]', which means the same thing as
353 `a[i]'. */
356 else
361 else
376 else
377 {
381 }
387 }
392 }
394 /* Given the cast expression EXP, checking out its validity. Either return
395 an error_mark_node if there was an unavoidable error, return a cast to
396 void for trying to delete a pointer w/ the value 0, or return the
397 call to delete. If DOING_VEC is true, we handle things differently
398 for doing an array delete.
399 Implements ARM $5.3.4. This is called from the parser. */
401 tree
403 {
410 {
416 }
418 /* An array can't have been allocated by new, so complain. */
426 {
430 }
434 /* As of Valley Forge, you can delete a pointer to const. */
436 /* You can't delete functions. */
438 {
442 }
444 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */
446 {
449 }
451 /* Deleting a pointer with the value zero is valid and has no effect. */
457 sfk_deleting_destructor,
458 use_global_delete);
459 else
462 }
464 /* Report an error if the indicated template declaration is not the
465 sort of thing that should be a member template. */
467 void
469 {
470 tree decl;
478 {
479 /* The parser rejects template declarations in local classes. */
482 {
483 /* 14.5.2.3 [temp.mem]
485 A member function template shall not be virtual. */
486 error
488 decl);
490 }
492 /* The debug-information generating code doesn't know what to do
493 with member templates. */
495 }
496 else
498 }
500 /* Return true iff TYPE is a valid Java parameter or return type. */
502 static bool
504 {
508 {
511 {
520 {
526 }
528 }
529 }
531 }
533 /* For a METHOD in a Java class CTYPE, return true if
534 the parameter and return types are valid Java types.
535 Otherwise, print appropriate error messages, and return false. */
537 bool
539 {
545 {
549 }
558 {
561 {
565 }
566 }
568 }
570 /* Sanity check: report error if this function FUNCTION is not
571 really a member of the class (CTYPE) it is supposed to belong to.
572 TEMPLATE_PARMS is used to specify the template parameters of a member
573 template passed as FUNCTION_DECL. If the member template is passed as a
574 TEMPLATE_DECL, it can be NULL since the parameters can be extracted
575 from the declaration. If the function is not a function template, it
576 must be NULL.
577 It returns the original declaration for the function, or NULL_TREE
578 if no declaration was found (and an error was emitted). */
580 tree
582 {
585 tree pushed_scope;
591 /* Since this is a specialization of a member template,
592 we're not going to find the declaration in the class.
593 For example, in:
595 struct S { template <typename T> void f(T); };
596 template <> void S::f(int);
598 we're not going to find `S::f(int)', but there's no
599 reason we should, either. We let our callers know we didn't
600 find the method, but we don't complain. */
603 /* Basic sanity check: for a template function, the template parameters
604 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */
606 {
611 }
613 /* OK, is this a definition of a member template? */
616 /* We must enter the scope here, because conversion operators are
617 named by target type, and type equivalence relies on typenames
618 resolving within the scope of CTYPE. */
622 {
630 {
637 /* We cannot simply call decls_match because this doesn't
638 work for static member functions that are pretending to
639 be methods, and because the name may have been changed by
640 asm("new_name"). */
642 /* Get rid of the this parameter on functions that become
643 static. */
648 /* A member template definition only matches a member template
649 declaration. */
656 && (!is_template
665 }
667 {
671 }
681 {
686 {
688 {
691 {
694 }
695 }
696 else
698 }
703 else
706 }
707 }
710 else
711 {
714 }
716 /* If we did not find the method in the class, add it to avoid
717 spurious errors (unless the CTYPE is not yet defined, in which
718 case we'll only confuse ourselves when the function is declared
719 properly within the class. */
726 }
728 /* DECL is a function with vague linkage. Remember it so that at the
729 end of the translation unit we can decide whether or not to emit
730 it. */
732 void
734 {
736 {
740 }
741 }
743 /* Like note_vague_linkage_fn but for variables. */
745 static void
747 {
749 }
751 /* We have just processed the DECL, which is a static data member.
752 The other parameters are as for cp_finish_decl. */
754 void
757 tree asmspec_tree,
759 {
764 /* We cannot call pushdecl here, because that would fill in the
765 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do
766 the right thing, namely, to put this decl out straight away. */
767 /* current_class_type can be NULL_TREE in case of error. */
778 /* Static consts need not be initialized in the class definition. */
780 {
785 {
788 }
790 }
791 /* Force the compiler to know when an uninitialized static const
792 member is being used. */
799 }
801 /* DECLARATOR and DECLSPECS correspond to a class member. The othe
802 parameters are as for cp_finish_decl. Return the DECL for the
803 class member declared. */
805 tree
809 tree asmspec_tree,
810 tree attrlist)
811 {
812 tree value;
824 /* friend or constructor went bad. */
828 {
831 }
833 /* Pass friendly classes back. */
837 /* Pass friend decls back. */
847 value);
849 /* Stash away type declarations. */
851 {
859 {
860 /* Avoid storing attributes in template parameters:
861 tsubst is not ready to handle them. */
866 else
868 }
871 }
874 {
877 }
883 {
885 {
886 /* Initializers for functions are rejected early in the parser.
887 If we get here, it must be a pure specifier for a method. */
889 {
892 }
893 else
894 {
897 value);
898 }
899 }
901 /* Already complained in grokdeclarator. */
904 {
907 else
911 {
912 /* We can allow references to things that are effectively
913 static, since references are initialized with the
914 address. */
918 {
921 }
922 }
923 }
924 }
928 {
932 }
938 {
964 /* Pass friends back this way. */
973 }
975 }
977 /* Like `grokfield', but for bitfields.
978 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */
980 tree
983 {
988 /* Pass friendly classes back. */
993 {
996 }
998 /* Usually, finish_struct_1 catches bitfields with invalid types.
999 But, in the case of bitfields with function type, we confuse
1000 ourselves into thinking they are member functions, so we must
1001 check here. */
1003 {
1007 }
1010 {
1014 }
1017 {
1020 }
1024 {
1028 }
1032 }
1034 \f
1035 void
1037 {
1048 }
1049 \f
1050 /* Walks through the namespace- or function-scope anonymous union
1051 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1052 Returns one of the fields for use in the mangled name. */
1054 static tree
1056 {
1058 tree field;
1060 /* Rather than write the code to handle the non-union case,
1061 just give an error. */
1068 {
1069 tree decl;
1070 tree ref;
1075 {
1079 }
1089 else
1094 {
1095 tree base;
1108 }
1111 else
1116 }
1119 }
1121 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1122 anonymous union, then all members must be laid out together. PUBLIC_P
1123 is nonzero if this union is not declared static. */
1125 void
1127 {
1128 tree type;
1129 tree main_decl;
1138 /* The VAR_DECL's context is the same as the TYPE's context. */
1145 {
1148 }
1154 {
1157 }
1160 {
1161 /* Use main_decl to set the mangled name. */
1165 }
1174 }
1175 \f
1176 /* Auxiliary functions to make type signatures for
1177 `operator new' and `operator delete' correspond to
1178 what compiler will be expecting. */
1180 tree
1182 {
1189 {
1192 }
1196 {
1202 }
1204 {
1207 /* Fall through. */
1209 type = build_exception_variant
1212 /* Fall through. */
1214 }
1216 }
1218 tree
1220 {
1227 {
1230 }
1234 {
1239 ptr_type_node);
1240 }
1242 {
1245 /* Fall through. */
1247 type = build_exception_variant
1250 /* Fall through. */
1252 }
1255 }
1256 \f
1257 static void
1259 {
1260 tree fnaddr;
1265 {
1266 tree fn;
1272 /* This entry is an offset: a virtual base class offset, a
1273 virtual call offset, an RTTI offset, etc. */
1278 /* When we don't have vcall offsets, we output thunks whenever
1279 we output the vtables that contain them. With vcall offsets,
1280 we know all the thunks we'll need when we emit a virtual
1281 function, so we emit the thunks there instead. */
1285 }
1286 }
1288 /* Set DECL up to have the closest approximation of "initialized common"
1289 linkage available. */
1291 void
1293 {
1298 /* We can just emit function and compiler-generated variables
1299 statically; having multiple copies is (for the most part) only
1300 a waste of space.
1302 There are two correctness issues, however: the address of a
1303 template instantiation with external linkage should be the
1304 same, independent of what translation unit asks for the
1305 address, and this will not hold when we emit multiple copies of
1306 the function. However, there's little else we can do.
1308 Also, by default, the typeinfo implementation assumes that
1309 there will be only one copy of the string used as the name for
1310 each type. Therefore, if weak symbols are unavailable, the
1311 run-time library should perform a more conservative check; it
1312 should perform a string comparison, rather than an address
1313 comparison. */
1315 else
1316 {
1317 /* Static data member template instantiations, however, cannot
1318 have multiple copies. */
1323 {
1326 }
1328 {
1329 /* We can't do anything useful; leave vars for explicit
1330 instantiation. */
1333 }
1334 }
1338 }
1340 /* For win32 we also want to put explicit instantiations in
1341 linkonce sections, so that they will be merged with implicit
1342 instantiations; otherwise we get duplicate symbol errors.
1343 For Darwin we do not want explicit instantiations to be
1344 linkonce. */
1346 void
1348 {
1349 /* We used to say that this was not necessary on targets that support weak
1350 symbols, because the implicit instantiations will defer to the explicit
1351 one. However, that's not actually the case in SVR4; a strong definition
1352 after a weak one is an error. Also, not making explicit
1353 instantiations one_only means that we can end up with two copies of
1354 some template instantiations. */
1358 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1359 we can get away with not emitting them if they aren't used. We need
1360 to for variables so that cp_finish_decl will update their linkage,
1361 because their DECL_INITIAL may not have been set properly yet. */
1366 {
1370 {
1372 /* Mark it needed so we don't forget to emit it. */
1374 }
1375 }
1376 }
1378 /* Determine whether or not we want to specifically import or export CTYPE,
1379 using various heuristics. */
1381 static void
1383 {
1384 /* -1 for imported, 1 for exported. */
1387 /* It only makes sense to call this function at EOF. The reason is
1388 that this function looks at whether or not the first non-inline
1389 non-abstract virtual member function has been defined in this
1390 translation unit. But, we can't possibly know that until we've
1391 seen the entire translation unit. */
1397 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1398 we will have CLASSTYPE_INTERFACE_ONLY set but not
1399 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1400 heuristic because someone will supply a #pragma implementation
1401 elsewhere, and deducing it here would produce a conflict. */
1411 /* For a template class, without -fimplicit-templates, check the
1412 repository. If the virtual table is assigned to this
1413 translation unit, then export the class; otherwise, import
1414 it. */
1417 {
1418 /* The ABI specifies that the virtual table and associated
1419 information are emitted with the key method, if any. */
1421 /* If weak symbol support is not available, then we must be
1422 careful not to emit the vtable when the key function is
1423 inline. An inline function can be defined in multiple
1424 translation units. If we were to emit the vtable in each
1425 translation unit containing a definition, we would get
1426 multiple definition errors at link-time. */
1429 }
1431 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1432 a definition anywhere else. */
1436 /* Allow backends the chance to overrule the decision. */
1441 {
1444 }
1445 }
1447 /* Return true if VAR has already been provided to the back end; in that
1448 case VAR should not be modified further by the front end. */
1449 static bool
1451 {
1453 }
1455 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1456 must be emitted in this translation unit. Mark it as such. */
1458 void
1460 {
1461 /* It's possible that we no longer need to set
1462 TREE_SYMBOL_REFERENCED here directly, but doing so is
1463 harmless. */
1466 }
1468 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
1469 returns true if a definition of this entity should be provided in
1470 this object file. Callers use this function to determine whether
1471 or not to let the back end know that a definition of DECL is
1472 available in this translation unit. */
1474 bool
1476 {
1479 /* This function should only be called at the end of the translation
1480 unit. We cannot be sure of whether or not something will be
1481 COMDAT until that point. */
1484 /* All entities with external linkage that are not COMDAT should be
1485 emitted; they may be referred to from other object files. */
1488 /* If this entity was used, let the back-end see it; it will decide
1489 whether or not to emit it into the object file. */
1494 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
1495 reference to DECL might cause it to be emitted later. */
1497 }
1499 /* If necessary, write out the vtables for the dynamic class CTYPE.
1500 Returns true if any vtables were emitted. */
1502 static bool
1504 {
1505 tree vtbl;
1506 tree primary_vtbl;
1509 /* If the vtables for this class have already been emitted there is
1510 nothing more to do. */
1514 /* Ignore dummy vtables made by get_vtable_decl. */
1518 /* On some targets, we cannot determine the key method until the end
1519 of the translation unit -- which is when this function is
1520 called. */
1524 /* See if any of the vtables are needed. */
1526 {
1530 }
1532 {
1533 /* If the references to this class' vtables are optimized away,
1534 still emit the appropriate debugging information. See
1535 dfs_debug_mark. */
1540 }
1542 /* The ABI requires that we emit all of the vtables if we emit any
1543 of them. */
1545 {
1546 /* Mark entities references from the virtual table as used. */
1550 {
1553 /* It had better be all done at compile-time. */
1555 }
1557 /* Write it out. */
1561 /* Because we're only doing syntax-checking, we'll never end up
1562 actually marking the variable as written. */
1565 }
1567 /* Since we're writing out the vtable here, also write the debug
1568 info. */
1572 }
1574 /* Like c_determine_visibility, but with additional C++-specific
1575 behavior. */
1577 void
1579 {
1580 tree class_type;
1582 /* Cloned constructors and destructors get the same visibility as
1583 the underlying function. That should be set up in
1584 maybe_clone_body. */
1587 /* Give the common code a chance to make a determination. */
1591 /* If DECL is a member of a class, visibility specifiers on the
1592 class can influence the visibility of the DECL. */
1599 else
1600 {
1601 /* Virtual tables have DECL_CONTEXT set to their associated class,
1602 so they are automatically handled above. */
1605 /* Entities not associated with any class just get the
1606 visibility specified by their attributes. */
1608 }
1610 /* By default, static data members and function members receive
1611 the visibility of their containing class. */
1613 {
1616 {
1619 }
1623 {
1624 /* Don't change it if it has been set explicitly by user. */
1626 {
1629 }
1630 }
1632 {
1635 }
1637 {
1640 }
1641 }
1642 }
1644 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
1645 for DECL has not already been determined, do so now by setting
1646 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
1647 function is called entities with vague linkage whose definitions
1648 are available must have TREE_PUBLIC set.
1650 If this function decides to place DECL in COMDAT, it will set
1651 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
1652 the caller to decide whether or not to clear DECL_EXTERNAL. Some
1653 callers defer that decision until it is clear that DECL is actually
1654 required. */
1656 void
1658 {
1667 /* We cannot determine what linkage to give to an entity with vague
1668 linkage until the end of the file. For example, a virtual table
1669 for a class will be defined if and only if the key method is
1670 defined in this translation unit. As a further example, consider
1671 that when compiling a translation unit that uses PCH file with
1672 "-frepo" it would be incorrect to make decisions about what
1673 entities to emit when building the PCH; those decisions must be
1674 delayed until the repository information has been processed. */
1676 /* Object file linkage for explicit instantiations is handled in
1677 mark_decl_instantiated. For static variables in functions with
1678 vague linkage, maybe_commonize_var is used.
1680 Therefore, the only declarations that should be provided to this
1681 function are those with external linkage that are:
1683 * implicit instantiations of function templates
1685 * inline function
1687 * implicit instantiations of static data members of class
1688 templates
1690 * virtual tables
1692 * typeinfo objects
1694 Furthermore, all entities that reach this point must have a
1695 definition available in this translation unit.
1697 The following assertions check these conditions. */
1700 /* Any code that creates entities with TREE_PUBLIC cleared should
1701 also set DECL_INTERFACE_KNOWN. */
1707 else
1711 /* Check that a definition of DECL is available in this translation
1712 unit. */
1715 /* Assume that DECL will not have COMDAT linkage. */
1717 /* Assume that DECL will not be imported into this translation
1718 unit. */
1721 /* See if the repository tells us whether or not to emit DECL in
1722 this translation unit. */
1727 {
1728 /* The repository indicates that this entity should be defined
1729 here. Make sure the back end honors that request. */
1734 {
1735 tree clone;
1738 }
1739 else
1741 /* Output the definition as an ordinary strong definition. */
1745 }
1748 /* We have already decided what to do with this DECL; there is no
1749 need to check anything further. */
1750 ;
1752 {
1764 /* The ABI requires that all virtual tables be emitted with
1765 COMDAT linkage. However, on systems where COMDAT symbols
1766 don't show up in the table of contents for a static
1767 archive, or on systems without weak symbols (where we
1768 approximate COMDAT linkage by using internal linkage), the
1769 linker will report errors about undefined symbols because
1770 it will not see the virtual table definition. Therefore,
1771 in the case that we know that the virtual table will be
1772 emitted in only one translation unit, we make the virtual
1773 table an ordinary definition with external linkage. */
1776 {
1777 /* CLASS_TYPE is being exported from this translation unit,
1778 so DECL should be defined here. */
1780 /* If a class is declared in a header with the "extern
1781 template" extension, then it will not be instantiated,
1782 even in translation units that would normally require
1783 it. Often such classes are explicitly instantiated in
1784 one translation unit. Therefore, the explicit
1785 instantiation must be made visible to other translation
1786 units. */
1788 else
1789 {
1790 /* The generic C++ ABI says that class data is always
1791 COMDAT, even if there is a key function. Some
1792 variants (e.g., the ARM EABI) says that class data
1793 only has COMDAT linkage if the class data might
1794 be emitted in more than one translation unit. */
1797 {
1798 /* The ABI requires COMDAT linkage. Normally, we
1799 only emit COMDAT things when they are needed;
1800 make sure that we realize that this entity is
1801 indeed needed. */
1804 }
1805 }
1806 }
1810 else
1812 }
1814 {
1817 {
1823 /* If -fno-rtti was specified, then we cannot be sure
1824 that RTTI information will be emitted with the
1825 virtual table of the class, so we must emit it
1826 wherever it is used. */
1829 else
1830 {
1833 {
1837 {
1840 }
1841 }
1842 else
1844 }
1845 }
1846 else
1848 }
1851 {
1852 /* DECL is an implicit instantiation of a function or static
1853 data member. */
1855 || (flag_implicit_inline_templates
1859 else
1860 /* If we are not implicitly generating templates, then mark
1861 this entity as undefined in this translation unit. */
1863 }
1865 {
1867 {
1871 {
1875 && ! flag_implement_inlines
1881 /* Always make artificials weak. */
1884 else
1886 }
1887 }
1888 else
1890 }
1891 else
1895 {
1896 /* If we are importing DECL into this translation unit, mark is
1897 an undefined here. */
1900 }
1902 {
1903 /* If we decided to put DECL in COMDAT, mark it accordingly at
1904 this point. */
1906 }
1908 /* Give the target a chance to override the visibility of class
1909 data, like virtual tables. */
1913 /* Construction virtual tables are not exported because
1914 they cannot be referred to from other object files;
1915 their name is not standardized by the ABI. */
1917 /* Visibility only applies to objects with external linkage. */
1919 /* Visibility is specified by the definition of the object, not
1920 its declaration. */
1922 /* Respect any explicit specification of visibility for the
1923 class data itself. */
1925 /* If the visibility of the class has been explicitly specified,
1926 that visibility applies to class data as well. */
1931 }
1933 /* Return an expression that performs the destruction of DECL, which
1934 must be a VAR_DECL whose type has a non-trivial destructor, or is
1935 an array whose (innermost) elements have a non-trivial destructor. */
1937 tree
1939 {
1940 tree temp;
1943 /* This function should only be called for declarations that really
1944 require cleanups. */
1947 /* Treat all objects with destructors as used; the destructor may do
1948 something substantive. */
1953 else
1954 {
1957 }
1959 sfk_complete_destructor,
1962 }
1964 /* Returns the initialization guard variable for the variable DECL,
1965 which has static storage duration. */
1967 tree
1969 {
1970 tree sname;
1971 tree guard;
1976 {
1977 tree guard_type;
1979 /* We use a type that is big enough to contain a mutex as well
1980 as an integer counter. */
1984 /* The guard should have the same linkage as what it guards. */
1996 }
1998 }
2000 /* Return those bits of the GUARD variable that should be set when the
2001 guarded entity is actually initialized. */
2003 static tree
2005 {
2007 {
2008 /* We only set the first byte of the guard, in order to leave room
2009 for a mutex in the high-order bits. */
2012 guard);
2015 guard);
2017 }
2020 }
2022 /* Return an expression which determines whether or not the GUARD
2023 variable has already been initialized. */
2025 tree
2027 {
2028 tree guard_value;
2030 /* Check to see if the GUARD is zero. */
2033 /* Mask off all but the low bit. */
2035 {
2040 }
2046 }
2048 /* Return an expression which sets the GUARD variable, indicating that
2049 the variable being guarded has been initialized. */
2051 tree
2053 {
2054 tree guard_init;
2056 /* Set the GUARD to one. */
2062 }
2064 /* Start the process of running a particular set of global constructors
2065 or destructors. Subroutine of do_[cd]tors. */
2067 static tree
2069 {
2070 tree body;
2071 tree fndecl;
2074 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
2077 {
2080 #ifdef JOINER
2082 #else
2084 #endif
2087 }
2088 else
2094 void_list_node));
2097 /* It can be a static function as long as collect2 does not have
2098 to scan the object file to find its ctor/dtor routine. */
2101 /* Mark this declaration as used to avoid spurious warnings. */
2104 /* Mark this function as a global constructor or destructor. */
2107 else
2113 /* We cannot allow these functions to be elided, even if they do not
2114 have external linkage. And, there's no point in deferring
2115 compilation of thes functions; they're all going to have to be
2116 out anyhow. */
2121 }
2123 /* Finish the process of running a particular set of global constructors
2124 or destructors. Subroutine of do_[cd]tors. */
2126 static void
2128 {
2129 tree fn;
2131 /* Finish up. */
2136 /* When only doing semantic analysis, and no RTL generation, we
2137 can't call functions that directly emit assembly code; there is
2138 no assembly file in which to put the code. */
2143 {
2148 else
2150 }
2151 }
2153 /* The names of the parameters to the function created to handle
2154 initializations and destructions for objects with static storage
2155 duration. */
2159 /* The name of the function we create to handle initializations and
2160 destructions for objects with static storage duration. */
2163 /* The declaration for the __INITIALIZE_P argument. */
2166 /* The declaration for the __PRIORITY argument. */
2169 /* The declaration for the static storage duration function. */
2172 /* All the static storage duration functions created in this
2173 translation unit. */
2176 /* A map from priority levels to information about that priority
2177 level. There may be many such levels, so efficient lookup is
2178 important. */
2181 /* Begins the generation of the function that will handle all
2182 initialization and destruction of objects with static storage
2183 duration. The function generated takes two parameters of type
2184 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
2185 nonzero, it performs initializations. Otherwise, it performs
2186 destructions. It only performs those initializations or
2187 destructions with the indicated __PRIORITY. The generated function
2188 returns no value.
2190 It is assumed that this function will only be called once per
2191 translation unit. */
2193 static tree
2195 {
2196 tree parm_types;
2197 tree type;
2198 tree body;
2201 /* Create the identifier for this function. It will be of the form
2202 SSDF_IDENTIFIER_<number>. */
2205 /* Create the parameters. */
2211 /* Create the FUNCTION_DECL itself. */
2214 type);
2218 /* Put this function in the list of functions to be called from the
2219 static constructors and destructors. */
2221 {
2224 /* Take this opportunity to initialize the map from priority
2225 numbers to information about that priority level. */
2228 /*delete_value_fn=*/
2231 /* We always need to generate functions for the
2232 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
2233 priorities later, we'll be sure to find the
2234 DEFAULT_INIT_PRIORITY. */
2236 }
2240 /* Create the argument list. */
2241 initialize_p_decl = cp_build_parm_decl
2245 priority_decl = cp_build_parm_decl
2253 /* Put the function in the global scope. */
2256 /* Start the function itself. This is equivalent to declaring the
2257 function as:
2259 static void __ssdf (int __initialize_p, init __priority_p);
2261 It is static because we only need to call this function from the
2262 various constructor and destructor functions for this module. */
2265 SF_PRE_PARSED);
2267 /* Set up the scope of the outermost block in the function. */
2270 /* This function must not be deferred because we are depending on
2271 its compilation to tell us what is TREE_SYMBOL_REFERENCED. */
2276 }
2278 /* Finish the generation of the function which performs initialization
2279 and destruction of objects with static storage duration. After
2280 this point, no more such objects can be created. */
2282 static void
2284 {
2285 /* Close out the function. */
2288 }
2290 /* Return the information about the indicated PRIORITY level. If no
2291 code to handle this level has yet been generated, generate the
2292 appropriate prologue. */
2294 static priority_info
2296 {
2297 priority_info pi;
2298 splay_tree_node n;
2303 {
2304 /* Create a new priority information structure, and insert it
2305 into the map. */
2312 }
2313 else
2317 }
2319 /* The effective initialization priority of a DECL. */
2321 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
2322 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
2323 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
2325 /* Whether a DECL needs a guard to protect it against multiple
2326 initialization. */
2328 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
2329 || DECL_ONE_ONLY (decl) \
2330 || DECL_WEAK (decl)))
2332 /* Set up to handle the initialization or destruction of DECL. If
2333 INITP is nonzero, we are initializing the variable. Otherwise, we
2334 are destroying it. */
2336 static void
2338 {
2340 tree guard;
2342 /* If we are supposed to destruct and there's a trivial destructor,
2343 nothing has to be done. */
2348 /* Trick the compiler into thinking we are at the file and line
2349 where DECL was declared so that error-messages make sense, and so
2350 that the debugger will show somewhat sensible file and line
2351 information. */
2354 /* Because of:
2356 [class.access.spec]
2358 Access control for implicit calls to the constructors,
2359 the conversion functions, or the destructor called to
2360 create and destroy a static data member is performed as
2361 if these calls appeared in the scope of the member's
2362 class.
2364 we pretend we are in a static member function of the class of
2365 which the DECL is a member. */
2367 {
2370 }
2372 /* Assume we don't need a guard. */
2374 /* We need a guard if this is an object with external linkage that
2375 might be initialized in more than one place. (For example, a
2376 static data member of a template, when the data member requires
2377 construction.) */
2379 {
2380 tree guard_cond;
2384 /* When using __cxa_atexit, we just check the GUARD as we would
2385 for a local static. */
2387 {
2388 /* When using __cxa_atexit, we never try to destroy
2389 anything from a static destructor. */
2392 }
2393 /* If we don't have __cxa_atexit, then we will be running
2394 destructors from .fini sections, or their equivalents. So,
2395 we need to know how many times we've tried to initialize this
2396 object. We do initializations only if the GUARD is zero,
2397 i.e., if we are the first to initialize the variable. We do
2398 destructions only if the GUARD is one, i.e., if we are the
2399 last to destroy the variable. */
2401 guard_cond
2404 guard,
2406 integer_one_node);
2407 else
2408 guard_cond
2411 guard,
2413 integer_zero_node);
2417 }
2420 /* If we're using __cxa_atexit, we have not already set the GUARD,
2421 so we must do so now. */
2425 /* Perform the initialization or destruction. */
2427 {
2431 /* If we're using __cxa_atexit, register a function that calls the
2432 destructor for the object. */
2435 }
2436 else
2439 /* Finish the guard if-stmt, if necessary. */
2441 {
2444 }
2446 /* Now that we're done with DECL we don't need to pretend to be a
2447 member of its class any longer. */
2450 }
2452 /* Generate code to do the initialization or destruction of the decls in VARS,
2453 a TREE_LIST of VAR_DECL with static storage duration.
2454 Whether initialization or destruction is performed is specified by INITP. */
2456 static void
2458 {
2461 /* Build the outer if-stmt to check for initialization or destruction. */
2465 initialize_p_decl,
2466 cond);
2472 tree priority_if_stmt;
2474 priority_info pi;
2476 /* If we don't need a destructor, there's nothing to do. Avoid
2477 creating a possibly empty if-stmt. */
2479 {
2482 }
2484 /* Remember that we had an initialization or finalization at this
2485 priority. */
2490 else
2493 /* Conditionalize this initialization on being in the right priority
2494 and being initializing/finalizing appropriately. */
2497 priority_decl,
2501 /* Process initializers with same priority. */
2505 /* Do one initialization or destruction. */
2509 /* Finish up the priority if-stmt body. */
2515 /* Finish up the init/destruct if-stmt body. */
2518 }
2520 /* VARS is a list of variables with static storage duration which may
2521 need initialization and/or finalization. Remove those variables
2522 that don't really need to be initialized or finalized, and return
2523 the resulting list. The order in which the variables appear in
2524 VARS is in reverse order of the order in which they should actually
2525 be initialized. The list we return is in the unreversed order;
2526 i.e., the first variable should be initialized first. */
2528 static tree
2530 {
2535 {
2540 /* Deal gracefully with error. */
2542 {
2545 }
2547 /* The only things that can be initialized are variables. */
2550 /* If this object is not defined, we don't need to do anything
2551 here. */
2553 {
2556 }
2558 /* Also, if the initializer already contains errors, we can bail
2559 out now. */
2562 {
2565 }
2567 /* This variable is going to need initialization and/or
2568 finalization, so we add it to the list. */
2572 }
2575 }
2577 /* Make sure we have told the back end about all the variables in
2578 VARS. */
2580 static void
2582 {
2583 tree v;
2586 {
2589 {
2592 }
2593 }
2594 }
2596 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
2597 (otherwise) that will initialize all gobal objects with static
2598 storage duration having the indicated PRIORITY. */
2600 static void
2603 {
2605 tree arguments;
2606 tree fndecl;
2607 tree body;
2611 #ifdef USE_MAPPED_LOCATION
2612 /* ??? */
2613 #else
2615 #endif
2617 /* We use `I' to indicate initialization and `D' to indicate
2618 destruction. */
2621 /* We emit the function lazily, to avoid generating empty
2622 global constructors and destructors. */
2625 /* For Objective-C++, we may need to initialize metadata found in this module.
2626 This must be done _before_ any other static initializations. */
2629 {
2632 }
2634 /* Call the static storage duration function with appropriate
2635 arguments. */
2637 {
2638 /* Calls to pure or const functions will expand to nothing. */
2640 {
2646 NULL_TREE);
2649 arguments);
2651 }
2652 }
2654 /* If we're generating code for the DEFAULT_INIT_PRIORITY, throw in
2655 calls to any functions marked with attributes indicating that
2656 they should be called at initialization- or destruction-time. */
2658 {
2659 tree fns;
2662 fns;
2664 {
2667 /* Calls to pure/const functions will expand to nothing. */
2669 {
2673 }
2674 }
2675 }
2677 /* Close out the function. */
2680 }
2682 /* Generate constructor and destructor functions for the priority
2683 indicated by N. */
2685 static int
2687 {
2692 /* Generate the functions themselves, but only if they are really
2693 needed. */
2701 /* Keep iterating. */
2703 }
2705 /* Called via LANGHOOK_CALLGRAPH_ANALYZE_EXPR. It is supposed to mark
2706 decls referenced from frontend specific constructs; it will be called
2707 only for language-specific tree nodes.
2709 Here we must deal with member pointers. */
2711 tree
2713 tree from ATTRIBUTE_UNUSED)
2714 {
2718 {
2729 {
2730 /* The ABI requires that all virtual tables be emitted
2731 whenever one of them is. */
2732 tree vtbl;
2734 vtbl;
2737 }
2740 /* If we need a static variable in a function, then we
2741 need the containing function. */
2746 }
2749 }
2751 /* Java requires that we be able to reference a local address for a
2752 method, and not be confused by PLT entries. If hidden aliases are
2753 supported, emit one for each java function that we've emitted. */
2755 static void
2757 {
2760 #ifndef HAVE_GAS_HIDDEN
2762 #endif
2765 {
2773 {
2774 /* Mangle the name in a predictable way; we need to reference
2775 this from a java compiled object file. */
2791 }
2792 }
2793 }
2795 /* This routine is called from the last rule in yyparse ().
2796 Its job is to create all the code needed to initialize and
2797 destroy the global aggregates. We do the destruction
2798 first, since that way we only need to reverse the decls once. */
2800 void
2802 {
2803 tree vars;
2806 location_t locus;
2809 tree decl;
2814 /* Bad parse errors. Just forget about it. */
2821 #ifdef USE_MAPPED_LOCATION
2822 /* FIXME - huh? */
2823 #else
2824 /* Otherwise, GDB can get confused, because in only knows
2825 about source for LINENO-1 lines. */
2827 #endif
2829 /* We now have to write out all the stuff we put off writing out.
2830 These include:
2832 o Template specializations that we have not yet instantiated,
2833 but which are needed.
2834 o Initialization and destruction for non-local objects with
2835 static storage duration. (Local objects with static storage
2836 duration are initialized when their scope is first entered,
2837 and are cleaned up via atexit.)
2838 o Virtual function tables.
2840 All of these may cause others to be needed. For example,
2841 instantiating one function may cause another to be needed, and
2842 generating the initializer for an object may cause templates to be
2843 instantiated, etc., etc. */
2849 do
2850 {
2851 tree t;
2852 tree decl;
2856 /* If there are templates that we've put off instantiating, do
2857 them now. */
2861 /* Write out virtual tables as required. Note that writing out
2862 the virtual table for a template class may cause the
2863 instantiation of members of that class. If we write out
2864 vtables then we remove the class from our list so we don't
2865 have to look at it again. */
2869 {
2872 }
2876 {
2880 {
2882 {
2885 }
2886 else
2890 }
2891 }
2893 /* Write out needed type info variables. We have to be careful
2894 looping through unemitted decls, because emit_tinfo_decl may
2895 cause other variables to be needed. New elements will be
2896 appended, and we remove from the vector those that actually
2897 get emitted. */
2901 {
2904 }
2906 /* The list of objects with static storage duration is built up
2907 in reverse order. We clear STATIC_AGGREGATES so that any new
2908 aggregates added during the initialization of these will be
2909 initialized in the correct order when we next come around the
2910 loop. */
2914 {
2915 /* We need to start a new initialization function each time
2916 through the loop. That's because we need to know which
2917 vtables have been referenced, and TREE_SYMBOL_REFERENCED
2918 isn't computed until a function is finished, and written
2919 out. That's a deficiency in the back-end. When this is
2920 fixed, these initialization functions could all become
2921 inline, with resulting performance improvements. */
2922 tree ssdf_body;
2924 /* Set the line and file, so that it is obviously not from
2925 the source file. */
2929 /* Make sure the back end knows about all the variables. */
2932 /* First generate code to do all the initializations. */
2936 /* Then, generate code to do all the destructions. Do these
2937 in reverse order so that the most recently constructed
2938 variable is the first destroyed. If we're using
2939 __cxa_atexit, then we don't need to do this; functions
2940 were registered at initialization time to destroy the
2941 local statics. */
2943 {
2946 }
2947 else
2950 /* Finish up the static storage duration function for this
2951 round. */
2955 /* All those initializations and finalizations might cause
2956 us to need more inline functions, more template
2957 instantiations, etc. */
2959 ssdf_count++;
2960 #ifdef USE_MAPPED_LOCATION
2961 /* ??? */
2962 #else
2964 #endif
2965 }
2967 /* Go through the set of inline functions whose bodies have not
2968 been emitted yet. If out-of-line copies of these functions
2969 are required, emit them. */
2971 {
2972 /* Does it need synthesizing? */
2975 {
2976 /* Even though we're already at the top-level, we push
2977 there again. That way, when we pop back a few lines
2978 hence, all of our state is restored. Otherwise,
2979 finish_function doesn't clean things up, and we end
2980 up with CURRENT_FUNCTION_DECL set. */
2982 /* The decl's location will mark where it was first
2983 needed. Save that so synthesize method can indicate
2984 where it was needed from, in case of error */
2989 }
2994 /* We lie to the back-end, pretending that some functions
2995 are not defined when they really are. This keeps these
2996 functions from being put out unnecessarily. But, we must
2997 stop lying when the functions are referenced, or if they
2998 are not comdat since they need to be put out now. If
2999 DECL_INTERFACE_KNOWN, then we have already set
3000 DECL_EXTERNAL appropriately, so there's no need to check
3001 again, and we do not want to clear DECL_EXTERNAL if a
3002 previous call to import_export_decl set it.
3004 This is done in a separate for cycle, because if some
3005 deferred function is contained in another deferred
3006 function later in deferred_fns varray,
3007 rest_of_compilation would skip this function and we
3008 really cannot expand the same function twice. */
3015 /* If we're going to need to write this function out, and
3016 there's already a body for it, create RTL for it now.
3017 (There might be no body if this is a method we haven't
3018 gotten around to synthesizing yet.) */
3023 {
3024 /* We will output the function; no longer consider it in this
3025 loop. */
3027 /* Generate RTL for this function now that we know we
3028 need it. */
3030 /* If we're compiling -fsyntax-only pretend that this
3031 function has been written out so that we don't try to
3032 expand it again. */
3036 }
3037 }
3042 /* Static data members are just like namespace-scope globals. */
3044 {
3048 /* If this static data member is needed, provide it to the
3049 back end. */
3052 }
3058 retries++;
3059 }
3062 /* All used inline functions must have a definition at this point. */
3064 {
3067 /* If the definition actually was available here, then the
3068 fact that the function was not defined merely represents
3069 that for some reason (use of a template repository,
3070 #pragma interface, etc.) we decided not to emit the
3071 definition here. */
3073 /* An explicit instantiation can be used to specify
3074 that the body is in another unit. It will have
3075 already verified there was a definition. */
3077 {
3079 /* Avoid a duplicate warning from check_global_declaration_1. */
3081 }
3082 }
3084 /* We give C linkage to static constructors and destructors. */
3087 /* Generate initialization and destruction functions for all
3088 priorities for which they are required. */
3091 generate_ctor_and_dtor_functions_for_priority,
3093 else
3094 {
3095 /* If we have a ctor or this is obj-c++ and we need a static init,
3096 call generate_ctor_or_dtor_function. */
3103 }
3105 /* We're done with the splay-tree now. */
3109 /* Generate any missing aliases. */
3112 /* We're done with static constructors, so we can go back to "C++"
3113 linkage now. */
3119 /* Now, issue warnings about static, but not defined, functions,
3120 etc., and emit debugging information. */
3123 {
3128 }
3130 /* Generate hidden aliases for Java. */
3135 /* The entire file is now complete. If requested, dump everything
3136 to a file. */
3137 {
3142 {
3145 }
3146 }
3151 {
3154 }
3157 #ifdef ENABLE_CHECKING
3160 }
3162 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
3163 function to call in parse-tree form; it has not yet been
3164 semantically analyzed. ARGS are the arguments to the function.
3165 They have already been semantically analyzed. */
3167 tree
3169 {
3170 tree orig_fn;
3171 tree orig_args;
3172 tree expr;
3173 tree object;
3180 {
3187 /* Transform the arguments and add the implicit "this"
3188 parameter. That must be done before the FN is transformed
3189 because we depend on the form of FN. */
3195 /* Now that the arguments are done, transform FN. */
3197 }
3199 /* A qualified name corresponding to a bound pointer-to-member is
3200 represented as an OFFSET_REF:
3202 struct B { void g(); };
3203 void (B::*p)();
3204 void B::g() { (this->*p)(); } */
3206 {
3211 }
3217 }
3220 void
3222 {
3227 {
3231 {
3234 }
3235 }
3236 }
3238 /* Mark DECL (eithet a _DECL or a BASELINK) as "used" in the program.
3239 If DECL is a specialization or implicitly declared class member,
3240 generate the actual definition. */
3242 void
3244 {
3247 /* If DECL is a BASELINK for a single function, then treat it just
3248 like the DECL for the function. Otherwise, if the BASELINK is
3249 for an overloaded function, we don't know which function was
3250 actually used until after overload resolution. */
3252 {
3257 }
3262 /* If we don't need a value, then we don't need to synthesize DECL. */
3265 /* Normally, we can wait until instantiation-time to synthesize
3266 DECL. However, if DECL is a static data member initialized with
3267 a constant, we need the value right now because a reference to
3268 such a data member is not value-dependent. */
3272 {
3273 /* Don't try to instantiate members of dependent types. We
3274 cannot just use dependent_type_p here because this function
3275 may be called from fold_non_dependent_expr, and then we may
3276 see dependent types, even though processing_template_decl
3277 will not be set. */
3281 /* Pretend that we are not in a template, even if we are, so
3282 that the static data member initializer will be processed. */
3285 }
3292 /* Remember it, so we can check it was defined. */
3293 {
3297 /* Remember the current location for a function we will end up
3298 synthesizing. Then we can inform the user where it was
3299 required in the case of error. */
3305 }
3309 /* Is it a synthesized method that needs to be synthesized? */
3315 /* Kludge: don't synthesize for default args. Unfortunately this
3316 rules out initializers of namespace-scoped objects too, but
3317 it's sort-of ok if the implicit ctor or dtor decl keeps
3318 pointing to the class location. */
3320 {
3322 /* If we've already synthesized the method we don't need to
3323 instantiate it, so we can return right away. */
3325 }
3327 /* If this is a function or variable that is an instance of some
3328 template, we now know that we will need to actually do the
3329 instantiation. We check that DECL is not an explicit
3330 instantiation because that is not checked in instantiate_decl. */
3337 /* We need to instantiate static data members so that there
3338 initializers are available in integral constant
3339 expressions. */
3342 /* We put off instantiating functions in order to improve compile
3343 times. Maintaining a stack of active functions is expensive,
3344 and the inliner knows to instantiate any functions it might
3345 need. */
3350 }