| blob | 2bde588847e9ed1a750e9165e181159bd049fc4c |
1 /* Process declarations and variables for C++ compiler.
2 Copyright (C) 1988-2017 Free Software Foundation, Inc.
3 Hacked by Michael Tiemann (tiemann@cygnus.com)
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
10 any later version.
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
22 /* Process declarations and symbol lookup for C++ front end.
23 Also constructs types; the standard scalar types at initialization,
24 and structure, union, array and enum types when they are declared. */
26 /* ??? not all decl nodes are given the most useful possible
27 line numbers. For example, the CONST_DECLs for enum values. */
52 /* Id for dumping the raw trees. */
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. */
88 /* A list of static class variables. This is needed, because a
89 static class variable can be declared inside the class without
90 an initializer, and then initialized, statically, outside the class. */
93 /* A list of functions which were declared inline, but which we
94 may need to emit outline anyway. */
97 /* A list of decls that use types with no linkage, which we need to make
98 sure are defined. */
101 /* A vector of alternating decls and identifiers, where the latter
102 is to be an alias for the former if the former is defined. */
105 /* Nonzero if we're done parsing and into end-of-file activities. */
109 /* True if note_mangling_alias should enqueue mangling aliases for
110 later generation, rather than emitting them right away. */
113 \f
115 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a
116 FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers
117 that apply to the function). */
119 tree
121 cp_ref_qualifier rqual)
122 {
123 tree raises;
124 tree attrs;
153 }
155 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its
156 return type changed to NEW_RET. */
158 tree
160 {
161 tree newtype;
174 {
179 }
180 else
181 newtype = build_method_type_directly
193 }
195 /* Build a PARM_DECL of FN with NAME and TYPE, and set DECL_ARG_TYPE
196 appropriately. */
198 tree
200 {
205 /* DECL_ARG_TYPE is only used by the back end and the back end never
206 sees templates. */
211 }
213 /* Returns a PARM_DECL of FN for a parameter of the indicated TYPE, with the
214 indicated NAME. */
216 tree
218 {
221 /* All our artificial parms are implicitly `const'; they cannot be
222 assigned to. */
225 }
227 /* Constructors for types with virtual baseclasses need an "in-charge" flag
228 saying whether this constructor is responsible for initialization of
229 virtual baseclasses or not. All destructors also need this "in-charge"
230 flag, which additionally determines whether or not the destructor should
231 free the memory for the object.
233 This function adds the "in-charge" flag to member function FN if
234 appropriate. It is called from grokclassfn and tsubst.
235 FN must be either a constructor or destructor.
237 The in-charge flag follows the 'this' parameter, and is followed by the
238 VTT parm (if any), then the user-written parms. */
240 void
242 {
245 /* If we've already add the in-charge parameter don't do it again. */
249 /* When processing templates we can't know, in general, whether or
250 not we're going to have virtual baseclasses. */
254 /* We don't need an in-charge parameter for constructors that don't
255 have virtual bases. */
266 /* If this is a subobject constructor or destructor, our caller will
267 pass us a pointer to our VTT. */
269 {
272 /* First add it to DECL_ARGUMENTS between 'this' and the real args... */
276 /* ...and then to TYPE_ARG_TYPES. */
280 }
282 /* Then add the in-charge parm (before the VTT parm). */
288 /* Insert our new parameter(s) into the list. */
291 /* And rebuild the function type. */
293 arg_types);
298 fntype = (cp_build_type_attribute_variant
302 /* Now we've got the in-charge parameter. */
304 }
306 /* Classes overload their constituent function names automatically.
307 When a function name is declared in a record structure,
308 its name is changed to it overloaded name. Since names for
309 constructors and destructors can conflict, we place a leading
310 '$' for destructors.
312 CNAME is the name of the class we are grokking for.
314 FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'.
316 FLAGS contains bits saying what's special about today's
317 arguments. DTOR_FLAG == DESTRUCTOR.
319 If FUNCTION is a destructor, then we must add the `auto-delete' field
320 as a second parameter. There is some hair associated with the fact
321 that we must "declare" this variable in the manner consistent with the
322 way the rest of the arguments were declared.
324 QUALS are the qualifiers for the this pointer. */
326 void
328 {
331 /* Even within an `extern "C"' block, members get C++ linkage. See
332 [dcl.link] for details. */
336 {
340 }
349 }
351 /* Create an ARRAY_REF, checking for the user doing things backwards
352 along the way. DECLTYPE_P is for N3276, as in the parser. */
354 tree
357 {
358 tree type;
359 tree expr;
368 {
375 }
381 /* If they have an `operator[]', use that. */
383 {
389 }
390 else
391 {
394 /* Otherwise, create an ARRAY_REF for a pointer or array type.
395 It is a little-known fact that, if `a' is an array and `i' is
396 an int, you can write `i[a]', which means the same thing as
397 `a[i]'. */
400 else
405 else
420 else
421 {
425 }
431 }
433 {
440 }
442 }
444 /* Given the cast expression EXP, checking out its validity. Either return
445 an error_mark_node if there was an unavoidable error, return a cast to
446 void for trying to delete a pointer w/ the value 0, or return the
447 call to delete. If DOING_VEC is true, we handle things differently
448 for doing an array delete.
449 Implements ARM $5.3.4. This is called from the parser. */
451 tree
453 tsubst_flags_t complain)
454 {
461 {
467 }
469 /* An array can't have been allocated by new, so complain. */
476 {
480 }
484 /* As of Valley Forge, you can delete a pointer to const. */
486 /* You can't delete functions. */
488 {
492 }
494 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */
496 {
499 }
501 /* Deleting a pointer with the value zero is valid and has no effect. */
507 sfk_deleting_destructor,
509 else
512 complain);
513 }
515 /* Report an error if the indicated template declaration is not the
516 sort of thing that should be a member template. */
518 void
520 {
521 tree decl;
530 {
531 /* The parser rejects template declarations in local classes
532 (with the exception of generic lambdas). */
534 /* The parser rejects any use of virtual in a function template. */
538 /* The debug-information generating code doesn't know what to do
539 with member templates. */
541 }
544 else
546 }
548 /* Sanity check: report error if this function FUNCTION is not
549 really a member of the class (CTYPE) it is supposed to belong to.
550 TEMPLATE_PARMS is used to specify the template parameters of a member
551 template passed as FUNCTION_DECL. If the member template is passed as a
552 TEMPLATE_DECL, it can be NULL since the parameters can be extracted
553 from the declaration. If the function is not a function template, it
554 must be NULL.
555 It returns the original declaration for the function, NULL_TREE if
556 no declaration was found, error_mark_node if an error was emitted. */
558 tree
560 {
565 /* Since this is a specialization of a member template,
566 we're not going to find the declaration in the class.
567 For example, in:
569 struct S { template <typename T> void f(T); };
570 template <> void S::f(int);
572 we're not going to find `S::f(int)', but there's no
573 reason we should, either. We let our callers know we didn't
574 find the method, but we don't complain. */
577 /* Basic sanity check: for a template function, the template parameters
578 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */
580 {
584 {
588 }
590 }
592 /* OK, is this a definition of a member template? */
595 /* [temp.mem]
597 A destructor shall not be a member template. */
599 {
602 }
604 /* We must enter the scope here, because conversion operators are
605 named by target type, and type equivalence relies on typenames
606 resolving within the scope of CTYPE. */
612 {
615 /* A member template definition only matches a member template
616 declaration. */
626 /* We cannot simply call decls_match because this doesn't work
627 for static member functions that are pretending to be
628 methods, and because the name may have been changed by
629 asm("new_name"). */
631 /* Get rid of the this parameter on functions that become
632 static. */
637 /* ref-qualifier or absence of same must match. */
642 // Include constraints in the match.
646 /* While finding a match, same types and params are not enough
647 if the function is versioned. Also check version ("target")
648 attributes. */
653 && (!is_template
662 }
665 {
668 else
669 {
680 else
685 }
687 }
693 }
695 /* DECL is a function with vague linkage. Remember it so that at the
696 end of the translation unit we can decide whether or not to emit
697 it. */
699 void
701 {
704 }
706 /* As above, but for variable template instantiations. */
708 void
710 {
712 }
714 /* We have just processed the DECL, which is a static data member.
715 The other parameters are as for cp_finish_decl. */
717 void
720 tree asmspec_tree,
722 {
725 /* We cannot call pushdecl here, because that would fill in the
726 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do
727 the right thing, namely, to put this decl out straight away. */
733 /* We already complained about the template definition. */
737 else
741 {
747 }
756 }
758 /* DECLARATOR and DECLSPECS correspond to a class member. The other
759 parameters are as for cp_finish_decl. Return the DECL for the
760 class member declared. */
762 tree
766 tree asmspec_tree,
767 tree attrlist)
768 {
769 tree value;
772 tree name;
782 /* friend or constructor went bad. */
788 {
791 }
793 /* Pass friendly classes back. */
801 {
803 {
806 }
811 value);
812 }
814 /* Stash away type declarations. */
816 {
821 {
824 /* If this is a typedef that names the class for linkage purposes
825 (7.1.3p8), apply any attributes directly to the type. */
831 }
838 /* It's important that push_template_decl below follows
839 set_underlying_type above so that the created template
840 carries the properly set type of VALUE. */
846 }
851 {
854 }
860 {
862 {
864 {
868 }
870 {
872 {
876 }
877 }
881 {
886 else
888 value);
889 }
890 else
891 {
895 value);
896 else
898 value);
899 }
900 }
905 }
907 /* Pass friend decls back. */
913 /* Need to set this before push_template_decl. */
918 {
922 }
929 else
933 {
958 /* Pass friends back this way. */
967 }
969 }
971 /* Like `grokfield', but for bitfields.
972 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */
974 tree
977 tree attrlist)
978 {
986 /* Pass friendly classes back. */
993 {
996 }
999 {
1002 }
1004 /* Usually, finish_struct_1 catches bitfields with invalid types.
1005 But, in the case of bitfields with function type, we confuse
1006 ourselves into thinking they are member functions, so we must
1007 check here. */
1009 {
1013 }
1016 {
1020 }
1023 {
1027 }
1030 {
1033 }
1037 {
1038 /* The width must be an integer type. */
1043 else
1044 {
1047 }
1048 }
1056 }
1058 \f
1059 /* Returns true iff ATTR is an attribute which needs to be applied at
1060 instantiation time rather than template definition time. */
1062 static bool
1064 {
1068 tree arg;
1071 /* Unknown attribute. */
1074 /* Attribute weak handling wants to write out assembly right away. */
1078 /* Attributes used and unused are applied directly, as they appertain to
1079 decls. */
1084 /* Attribute tls_model wants to modify the symtab. */
1088 /* #pragma omp declare simd attribute needs to be always deferred. */
1093 /* An attribute pack is clearly dependent. */
1097 /* If any of the arguments are dependent expressions, we can't evaluate
1098 the attribute until instantiation time. */
1100 {
1103 /* If the first attribute argument is an identifier, only consider
1104 second and following arguments. Attributes like mode, format,
1105 cleanup and several target specific attributes aren't late
1106 just because they have an IDENTIFIER_NODE as first argument. */
1114 }
1119 {
1122 /* We can't apply any attributes to a completely unknown type until
1123 instantiation time. */
1129 /* Also defer most attributes on dependent types. This is not
1130 necessary in all cases, but is the better default. */
1132 /* But some attributes specifically apply to templates. */
1137 else
1139 }
1140 else
1142 }
1144 /* ATTR_P is a list of attributes. Remove any attributes which need to be
1145 applied at instantiation time and return them. If IS_DEPENDENT is true,
1146 the declaration itself is dependent, so all attributes should be applied
1147 at instantiation time. */
1149 static tree
1151 {
1160 {
1162 {
1168 }
1169 else
1171 }
1174 }
1176 /* Remove any late attributes from the list in ATTR_P and attach them to
1177 DECL_P. */
1179 static void
1181 {
1193 else
1198 /* Merge the late attributes at the beginning with the attribute
1199 list. */
1204 {
1205 /* We've added new attributes directly to the main variant, so
1206 now we need to update all of the other variants to include
1207 these new attributes. */
1208 tree variant;
1211 {
1214 }
1215 }
1216 }
1218 /* True if ATTRS contains any dependent attributes that affect type
1219 identity. */
1221 bool
1223 {
1226 {
1230 }
1232 }
1234 /* Return true iff ATTRS are acceptable attributes to be applied in-place
1235 to a typedef which gives a previously unnamed class or enum a name for
1236 linkage purposes. */
1238 bool
1240 {
1242 {
1246 }
1248 }
1250 /* Like reconstruct_complex_type, but handle also template trees. */
1252 tree
1254 {
1259 {
1263 }
1265 {
1269 }
1271 {
1274 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the
1275 element type qualification will be handled by the recursive
1276 cp_reconstruct_complex_type call and cp_build_qualified_type
1277 for ARRAY_TYPEs changes the element type. */
1279 }
1281 {
1288 }
1290 {
1293 /* The build_method_type_directly() routine prepends 'this' to argument list,
1294 so we must compensate by getting rid of it. */
1295 outer
1296 = build_method_type_directly
1299 }
1301 {
1304 }
1305 else
1316 }
1318 /* Replaces any constexpr expression that may be into the attributes
1319 arguments with their reduced value. */
1321 static void
1323 {
1327 tree attr;
1329 {
1330 tree arg;
1332 {
1336 }
1337 }
1338 }
1340 /* Return true if TYPE is an OpenMP mappable type. */
1341 bool
1343 {
1344 /* Mappable type has to be complete. */
1347 /* Arrays have mappable type if the elements have mappable type. */
1350 /* A mappable type cannot contain virtual members. */
1353 /* All data members must be non-static. */
1355 {
1356 tree field;
1360 /* All fields must have mappable types. */
1364 }
1366 }
1368 /* Like decl_attributes, but handle C++ complexity. */
1370 void
1372 {
1377 /* Add implicit "omp declare target" attribute if requested. */
1382 {
1392 else
1395 }
1398 {
1403 }
1411 {
1412 attributes
1416 }
1417 else
1423 /* Propagate deprecation out to the template. */
1426 {
1432 }
1433 }
1434 \f
1435 /* Walks through the namespace- or function-scope anonymous union
1436 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1437 Returns one of the fields for use in the mangled name. */
1439 static tree
1441 {
1443 tree field;
1445 /* Rather than write the code to handle the non-union case,
1446 just give an error. */
1448 {
1451 }
1456 {
1457 tree decl;
1458 tree ref;
1463 {
1465 "%q#D invalid; an anonymous union can only "
1468 }
1480 else
1485 {
1486 tree base;
1502 }
1505 else
1510 }
1513 }
1515 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1516 anonymous union, then all members must be laid out together. PUBLIC_P
1517 is nonzero if this union is not declared static. */
1519 void
1521 {
1522 tree type;
1523 tree main_decl;
1532 /* The VAR_DECL's context is the same as the TYPE's context. */
1539 {
1542 }
1548 {
1551 }
1554 {
1555 /* Use main_decl to set the mangled name. */
1561 }
1565 }
1566 \f
1567 /* Auxiliary functions to make type signatures for
1568 `operator new' and `operator delete' correspond to
1569 what compiler will be expecting. */
1571 tree
1573 {
1580 {
1583 }
1586 {
1588 {
1589 /* [basic.stc.dynamic.allocation]
1591 The first parameter shall not have an associated default
1592 argument. */
1595 /* Throw away the default argument. */
1597 }
1600 {
1603 }
1604 }
1605 else
1613 {
1616 /* Fall through. */
1618 type = build_exception_variant
1621 /* Fall through. */
1623 }
1625 }
1627 tree
1629 {
1636 {
1639 }
1643 {
1648 ptr_type_node);
1649 }
1651 {
1654 /* Fall through. */
1656 type = build_exception_variant
1659 /* Fall through. */
1661 }
1664 }
1665 \f
1666 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1667 and mark them as needed. */
1669 static void
1671 {
1672 tree fnaddr;
1675 /* It's OK for the vtable to refer to deprecated virtual functions. */
1680 {
1681 tree fn;
1687 /* This entry is an offset: a virtual base class offset, a
1688 virtual call offset, an RTTI offset, etc. */
1693 /* When we don't have vcall offsets, we output thunks whenever
1694 we output the vtables that contain them. With vcall offsets,
1695 we know all the thunks we'll need when we emit a virtual
1696 function, so we emit the thunks there instead. */
1700 }
1701 }
1703 /* Set DECL up to have the closest approximation of "initialized common"
1704 linkage available. */
1706 void
1708 {
1713 /* We can just emit function and compiler-generated variables
1714 statically; having multiple copies is (for the most part) only
1715 a waste of space.
1717 There are two correctness issues, however: the address of a
1718 template instantiation with external linkage should be the
1719 same, independent of what translation unit asks for the
1720 address, and this will not hold when we emit multiple copies of
1721 the function. However, there's little else we can do.
1723 Also, by default, the typeinfo implementation assumes that
1724 there will be only one copy of the string used as the name for
1725 each type. Therefore, if weak symbols are unavailable, the
1726 run-time library should perform a more conservative check; it
1727 should perform a string comparison, rather than an address
1728 comparison. */
1730 else
1731 {
1732 /* Static data member template instantiations, however, cannot
1733 have multiple copies. */
1738 {
1741 }
1743 {
1744 /* We can't do anything useful; leave vars for explicit
1745 instantiation. */
1748 }
1749 }
1753 }
1755 /* For win32 we also want to put explicit instantiations in
1756 linkonce sections, so that they will be merged with implicit
1757 instantiations; otherwise we get duplicate symbol errors.
1758 For Darwin we do not want explicit instantiations to be
1759 linkonce. */
1761 void
1763 {
1764 /* We used to say that this was not necessary on targets that support weak
1765 symbols, because the implicit instantiations will defer to the explicit
1766 one. However, that's not actually the case in SVR4; a strong definition
1767 after a weak one is an error. Also, not making explicit
1768 instantiations one_only means that we can end up with two copies of
1769 some template instantiations. */
1773 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1774 we can get away with not emitting them if they aren't used. We need
1775 to for variables so that cp_finish_decl will update their linkage,
1776 because their DECL_INITIAL may not have been set properly yet. */
1781 {
1785 {
1788 /* Mark it needed so we don't forget to emit it. */
1791 }
1792 }
1793 }
1795 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1796 This predicate will give the right answer during parsing of the
1797 function, which other tests may not. */
1799 bool
1801 {
1803 {
1804 /* maybe_thunk_body clears TREE_PUBLIC on the maybe-in-charge 'tor
1805 variants, check one of the "clones" for the real linkage. */
1814 }
1815 /* Unfortunately, import_export_decl has not always been called
1816 before the function is processed, so we cannot simply check
1817 DECL_COMDAT. */
1826 /* A local static in an inline effectively has vague linkage. */
1829 else
1831 }
1833 /* Determine whether or not we want to specifically import or export CTYPE,
1834 using various heuristics. */
1836 static void
1838 {
1839 /* -1 for imported, 1 for exported. */
1842 /* It only makes sense to call this function at EOF. The reason is
1843 that this function looks at whether or not the first non-inline
1844 non-abstract virtual member function has been defined in this
1845 translation unit. But, we can't possibly know that until we've
1846 seen the entire translation unit. */
1852 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1853 we will have CLASSTYPE_INTERFACE_ONLY set but not
1854 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1855 heuristic because someone will supply a #pragma implementation
1856 elsewhere, and deducing it here would produce a conflict. */
1866 /* For a template class, without -fimplicit-templates, check the
1867 repository. If the virtual table is assigned to this
1868 translation unit, then export the class; otherwise, import
1869 it. */
1872 {
1873 /* The ABI specifies that the virtual table and associated
1874 information are emitted with the key method, if any. */
1876 /* If weak symbol support is not available, then we must be
1877 careful not to emit the vtable when the key function is
1878 inline. An inline function can be defined in multiple
1879 translation units. If we were to emit the vtable in each
1880 translation unit containing a definition, we would get
1881 multiple definition errors at link-time. */
1884 }
1886 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1887 a definition anywhere else. */
1891 /* Allow back ends the chance to overrule the decision. */
1896 {
1899 }
1900 }
1902 /* Return true if VAR has already been provided to the back end; in that
1903 case VAR should not be modified further by the front end. */
1904 static bool
1906 {
1908 }
1910 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1911 must be emitted in this translation unit. Mark it as such. */
1913 void
1915 {
1918 {
1919 /* Extern inline functions don't become needed when referenced.
1920 If we know a method will be emitted in other TU and no new
1921 functions can be marked reachable, just use the external
1922 definition. */
1926 /* #pragma interface and -frepo code can call mark_needed for
1927 maybe-in-charge 'tors; mark the clones as well. */
1928 tree clone;
1931 }
1933 {
1935 /* C++ frontend use mark_decl_references to force COMDAT variables
1936 to be output that might appear dead otherwise. */
1938 }
1939 }
1941 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
1942 returns true if a definition of this entity should be provided in
1943 this object file. Callers use this function to determine whether
1944 or not to let the back end know that a definition of DECL is
1945 available in this translation unit. */
1947 bool
1949 {
1951 /* This function should only be called at the end of the translation
1952 unit. We cannot be sure of whether or not something will be
1953 COMDAT until that point. */
1956 /* All entities with external linkage that are not COMDAT/EXTERN should be
1957 emitted; they may be referred to from other object files. */
1960 /* Functions marked "dllexport" must be emitted so that they are
1961 visible to other DLLs. */
1966 /* When not optimizing, do not bother to produce definitions for extern
1967 symbols. */
1976 /* If this entity was used, let the back end see it; it will decide
1977 whether or not to emit it into the object file. */
1981 /* Virtual functions might be needed for devirtualization. */
1987 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
1988 reference to DECL might cause it to be emitted later. */
1990 }
1992 /* If necessary, write out the vtables for the dynamic class CTYPE.
1993 Returns true if any vtables were emitted. */
1995 static bool
1997 {
1998 tree vtbl;
1999 tree primary_vtbl;
2003 /* If the vtables for this class have already been emitted there is
2004 nothing more to do. */
2008 /* Ignore dummy vtables made by get_vtable_decl. */
2012 /* On some targets, we cannot determine the key method until the end
2013 of the translation unit -- which is when this function is
2014 called. */
2018 /* See if any of the vtables are needed. */
2020 {
2024 }
2026 {
2027 /* If the references to this class' vtables are optimized away,
2028 still emit the appropriate debugging information. See
2029 dfs_debug_mark. */
2034 }
2036 /* The ABI requires that we emit all of the vtables if we emit any
2037 of them. */
2039 {
2040 /* Mark entities references from the virtual table as used. */
2044 {
2047 LOOKUP_NORMAL);
2049 /* It had better be all done at compile-time. */
2051 }
2053 /* Write it out. */
2057 /* Because we're only doing syntax-checking, we'll never end up
2058 actually marking the variable as written. */
2062 {
2067 }
2068 }
2070 /* Since we're writing out the vtable here, also write the debug
2071 info. */
2075 }
2077 /* A special return value from type_visibility meaning internal
2078 linkage. */
2082 /* walk_tree helper function for type_visibility. */
2084 static tree
2086 {
2089 {
2091 }
2094 {
2097 }
2102 }
2104 /* Returns the visibility of TYPE, which is the minimum visibility of its
2105 component types. */
2107 static int
2109 {
2113 }
2115 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2116 specified (or if VISIBILITY is static). If TMPL is true, this
2117 constraint is for a template argument, and takes precedence
2118 over explicitly-specified visibility on the template. */
2120 static void
2122 {
2124 {
2125 /* extern "C" declarations aren't affected by the anonymous
2126 namespace. */
2128 {
2134 {
2139 }
2143 }
2144 }
2147 {
2149 /* This visibility was not specified. */
2151 }
2152 }
2154 /* Constrain the visibility of DECL based on the visibility of its template
2155 arguments. */
2157 static void
2159 {
2160 /* If this is a template instantiation, check the innermost
2161 template args for visibility constraints. The outer template
2162 args are covered by the class check. */
2166 {
2172 else
2173 {
2181 {
2184 else
2186 }
2187 }
2190 }
2191 }
2193 /* Like c_determine_visibility, but with additional C++-specific
2194 behavior.
2196 Function-scope entities can rely on the function's visibility because
2197 it is set in start_preparsed_function.
2199 Class-scope entities cannot rely on the class's visibility until the end
2200 of the enclosing class definition.
2202 Note that because namespaces have multiple independent definitions,
2203 namespace visibility is handled elsewhere using the #pragma visibility
2204 machinery rather than by decorating the namespace declaration.
2206 The goal is for constraints from the type to give a diagnostic, and
2207 other constraints to be applied silently. */
2209 void
2211 {
2212 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2214 /* Only relevant for names with external linkage. */
2218 /* Cloned constructors and destructors get the same visibility as
2219 the underlying function. That should be set up in
2220 maybe_clone_body. */
2226 /* The decl may be a template instantiation, which could influence
2227 visibilty. */
2230 {
2232 {
2235 }
2238 }
2242 /* If DECL is a member of a class, visibility specifiers on the
2243 class can influence the visibility of the DECL. */
2247 else
2248 {
2249 /* Not a class member. */
2251 /* Virtual tables have DECL_CONTEXT set to their associated class,
2252 so they are automatically handled above. */
2257 {
2258 /* Local statics and classes get the visibility of their
2259 containing function by default, except that
2260 -fvisibility-inlines-hidden doesn't affect them. */
2263 {
2267 }
2268 else
2269 {
2273 {
2277 }
2278 else
2279 {
2283 }
2284 }
2286 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2287 but have no TEMPLATE_INFO. Their containing template
2288 function does, and the local class could be constrained
2289 by that. */
2292 }
2295 {
2296 /* Under -fvisibility-ms-compat, types are visible by default,
2297 even though their contents aren't. */
2304 else
2306 }
2308 {
2309 /* tinfo visibility is based on the type it's for. */
2310 constrain_visibility
2313 /* Give the target a chance to override the visibility associated
2314 with DECL. */
2320 }
2322 /* Template instantiations and specializations get visibility based
2325 {
2328 else
2329 {
2330 /* Set default visibility to whatever the user supplied with
2331 #pragma GCC visibility or a namespace visibility attribute. */
2334 }
2335 }
2336 }
2339 {
2340 /* If the specialization doesn't specify visibility, use the
2341 visibility from the template. */
2349 {
2353 {
2357 else
2358 {
2362 }
2363 }
2366 /* Template argument visibility outweighs #pragma or namespace
2367 visibility, but not an explicit attribute. */
2369 {
2372 {
2373 /* A class template member with explicit visibility
2374 overrides the class visibility, so we need to apply
2375 all the levels of template args directly. */
2378 {
2381 }
2382 }
2384 /* Limit visibility based on its template arguments. */
2386 }
2387 }
2388 }
2394 /* Names in an anonymous namespace get internal linkage.
2395 This might change once we implement export. */
2398 {
2399 /* Propagate anonymity from type to decl. */
2404 }
2406 /* DR 757: A type without linkage shall not be used as the type of a
2407 variable or function with linkage, unless
2408 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2409 o the variable or function is not used (3.2 [basic.def.odr]) or is
2410 defined in the same translation unit.
2412 Since non-extern "C" decls need to be defined in the same
2413 translation unit, we can make the type internal. */
2416 /* If visibility changed and DECL already has DECL_RTL, ensure
2417 symbol flags are updated. */
2424 }
2426 /* By default, static data members and function members receive
2427 the visibility of their containing class. */
2429 static void
2431 {
2437 else
2438 {
2439 /* Default to the class visibility. */
2443 }
2445 /* Give the target a chance to override the visibility associated
2446 with DECL. */
2450 /* Construction virtual tables are not exported because
2451 they cannot be referred to from other object files;
2452 their name is not standardized by the ABI. */
2458 }
2460 /* Returns true iff DECL is an inline that should get hidden visibility
2461 because of -fvisibility-inlines-hidden. */
2463 static bool
2465 {
2467 /* Don't do this for inline templates; specializations might not be
2468 inline, and we don't want them to inherit the hidden
2469 visibility. We'll set it here for all inline instantiations. */
2470 && !processing_template_decl
2475 }
2477 /* Constrain the visibility of a class TYPE based on the visibility of its
2478 field types. Warn if any fields require lesser visibility. */
2480 void
2482 {
2483 tree binfo;
2484 tree t;
2493 /* Don't warn about visibility if the class has explicit visibility. */
2499 {
2504 {
2506 {
2509 {
2514 else
2518 }
2519 else
2523 }
2524 }
2531 }
2535 {
2539 {
2541 {
2544 {
2549 else
2553 }
2554 else
2558 }
2559 }
2565 }
2566 }
2568 /* Functions for adjusting the visibility of a tagged type and its nested
2569 types and declarations when it gets a name for linkage purposes from a
2570 typedef. */
2575 /* First reset the visibility of all the types. */
2577 static void
2579 {
2584 }
2585 static void
2587 {
2589 }
2591 /* Then reset the visibility of any static data members or member
2592 functions that use those types. */
2594 static void
2596 {
2605 }
2607 static void
2609 {
2611 {
2613 {
2618 }
2620 {
2626 }
2628 {
2632 }
2635 }
2636 }
2638 static void
2640 {
2642 }
2643 void
2645 {
2648 }
2650 /* Set up our initial idea of what the linkage of DECL should be. */
2652 void
2654 {
2656 /* We've already made a decision as to how this function will
2659 {
2662 {
2666 /* A non-template inline function with external linkage will
2667 always be COMDAT. As we must eventually determine the
2668 linkage of all functions, and as that causes writes to
2669 the data mapped in from the PCH file, it's advantageous
2670 to mark the functions at this point. */
2674 {
2675 /* This function must have external linkage, as
2676 otherwise DECL_INTERFACE_KNOWN would have been
2677 set. */
2681 }
2682 }
2685 }
2686 }
2688 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2689 for DECL has not already been determined, do so now by setting
2690 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2691 function is called entities with vague linkage whose definitions
2692 are available must have TREE_PUBLIC set.
2694 If this function decides to place DECL in COMDAT, it will set
2695 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2696 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2697 callers defer that decision until it is clear that DECL is actually
2698 required. */
2700 void
2702 {
2711 /* We cannot determine what linkage to give to an entity with vague
2712 linkage until the end of the file. For example, a virtual table
2713 for a class will be defined if and only if the key method is
2714 defined in this translation unit. As a further example, consider
2715 that when compiling a translation unit that uses PCH file with
2716 "-frepo" it would be incorrect to make decisions about what
2717 entities to emit when building the PCH; those decisions must be
2718 delayed until the repository information has been processed. */
2720 /* Object file linkage for explicit instantiations is handled in
2721 mark_decl_instantiated. For static variables in functions with
2722 vague linkage, maybe_commonize_var is used.
2724 Therefore, the only declarations that should be provided to this
2725 function are those with external linkage that are:
2727 * implicit instantiations of function templates
2729 * inline function
2731 * implicit instantiations of static data members of class
2732 templates
2734 * virtual tables
2736 * typeinfo objects
2738 Furthermore, all entities that reach this point must have a
2739 definition available in this translation unit.
2741 The following assertions check these conditions. */
2743 /* Any code that creates entities with TREE_PUBLIC cleared should
2744 also set DECL_INTERFACE_KNOWN. */
2750 else
2754 /* Check that a definition of DECL is available in this translation
2755 unit. */
2758 /* Assume that DECL will not have COMDAT linkage. */
2760 /* Assume that DECL will not be imported into this translation
2761 unit. */
2764 /* See if the repository tells us whether or not to emit DECL in
2765 this translation unit. */
2770 {
2771 /* The repository indicates that this entity should be defined
2772 here. Make sure the back end honors that request. */
2774 /* Output the definition as an ordinary strong definition. */
2778 }
2781 /* We have already decided what to do with this DECL; there is no
2782 need to check anything further. */
2783 ;
2785 {
2795 /* The ABI requires that all virtual tables be emitted with
2796 COMDAT linkage. However, on systems where COMDAT symbols
2797 don't show up in the table of contents for a static
2798 archive, or on systems without weak symbols (where we
2799 approximate COMDAT linkage by using internal linkage), the
2800 linker will report errors about undefined symbols because
2801 it will not see the virtual table definition. Therefore,
2802 in the case that we know that the virtual table will be
2803 emitted in only one translation unit, we make the virtual
2804 table an ordinary definition with external linkage. */
2807 {
2808 /* CLASS_TYPE is being exported from this translation unit,
2809 so DECL should be defined here. */
2811 /* If a class is declared in a header with the "extern
2812 template" extension, then it will not be instantiated,
2813 even in translation units that would normally require
2814 it. Often such classes are explicitly instantiated in
2815 one translation unit. Therefore, the explicit
2816 instantiation must be made visible to other translation
2817 units. */
2819 else
2820 {
2821 /* The generic C++ ABI says that class data is always
2822 COMDAT, even if there is a key function. Some
2823 variants (e.g., the ARM EABI) says that class data
2824 only has COMDAT linkage if the class data might be
2825 emitted in more than one translation unit. When the
2826 key method can be inline and is inline, we still have
2827 to arrange for comdat even though
2828 class_data_always_comdat is false. */
2832 {
2833 /* The ABI requires COMDAT linkage. Normally, we
2834 only emit COMDAT things when they are needed;
2835 make sure that we realize that this entity is
2836 indeed needed. */
2839 }
2840 }
2841 }
2845 else
2847 }
2849 {
2852 {
2858 /* If -fno-rtti was specified, then we cannot be sure
2859 that RTTI information will be emitted with the
2860 virtual table of the class, so we must emit it
2861 wherever it is used. */
2864 else
2865 {
2868 {
2874 {
2877 }
2878 }
2879 else
2881 }
2882 }
2883 else
2885 }
2887 {
2888 /* DECL is an implicit instantiation of a function or static
2889 data member. */
2892 || (flag_implicit_inline_templates
2896 else
2897 /* If we are not implicitly generating templates, then mark
2898 this entity as undefined in this translation unit. */
2900 }
2902 {
2904 {
2908 {
2912 && ! flag_implement_inlines
2918 /* Always make artificials weak. */
2921 else
2923 }
2924 }
2925 else
2927 }
2928 else
2932 {
2933 /* If we are importing DECL into this translation unit, mark is
2934 an undefined here. */
2937 }
2939 {
2940 /* If we decided to put DECL in COMDAT, mark it accordingly at
2941 this point. */
2943 }
2946 }
2948 /* Return an expression that performs the destruction of DECL, which
2949 must be a VAR_DECL whose type has a non-trivial destructor, or is
2950 an array whose (innermost) elements have a non-trivial destructor. */
2952 tree
2954 {
2958 }
2960 /* Returns the initialization guard variable for the variable DECL,
2961 which has static storage duration. */
2963 tree
2965 {
2966 tree sname;
2967 tree guard;
2972 {
2973 tree guard_type;
2975 /* We use a type that is big enough to contain a mutex as well
2976 as an integer counter. */
2981 /* The guard should have the same linkage as what it guards. */
2999 }
3001 }
3003 /* Return an atomic load of src with the appropriate memory model. */
3005 static tree
3007 {
3022 }
3024 /* Return those bits of the GUARD variable that should be set when the
3025 guarded entity is actually initialized. */
3027 static tree
3029 {
3031 {
3032 /* We only set the first byte of the guard, in order to leave room
3033 for a mutex in the high-order bits. */
3036 guard);
3039 guard);
3041 }
3044 }
3046 /* Return an expression which determines whether or not the GUARD
3047 variable has already been initialized. */
3049 tree
3051 {
3052 tree guard_value;
3056 else
3059 /* Mask off all but the low bit. */
3061 {
3067 tf_warning_or_error);
3068 }
3075 tf_warning_or_error);
3076 }
3078 /* Return an expression which sets the GUARD variable, indicating that
3079 the variable being guarded has been initialized. */
3081 tree
3083 {
3084 tree guard_init;
3086 /* Set the GUARD to one. */
3092 tf_warning_or_error);
3093 }
3095 /* Returns true iff we can tell that VAR does not have a dynamic
3096 initializer. */
3098 static bool
3100 {
3101 /* If it's defined in another TU, we can't tell. */
3104 /* If it has a non-trivial destructor, registering the destructor
3105 counts as dynamic initialization. */
3108 /* If it's in this TU, its initializer has been processed, unless
3109 it's a case of self-initialization, then DECL_INITIALIZED_P is
3110 false while the initializer is handled by finish_id_expression. */
3113 /* If it has no initializer or a constant one, it's not dynamic. */
3116 }
3118 /* Returns true iff VAR is a variable that needs uses to be
3119 wrapped for possible dynamic initialization. */
3121 static bool
3123 {
3129 }
3131 /* Get the FUNCTION_DECL for the shared TLS init function for this
3132 translation unit. */
3134 static tree
3136 {
3140 {
3143 void_list_node));
3149 }
3151 }
3153 /* Get a FUNCTION_DECL for the init function for the thread_local
3154 variable VAR. The init function will be an alias to the function
3155 that initializes all the non-local TLS variables in the translation
3156 unit. The init function is only used by the wrapper function. */
3158 static tree
3160 {
3161 /* Only C++11 TLS vars need this init fn. */
3165 /* If -fno-extern-tls-init, assume that we don't need to call
3166 a tls init function for a variable defined in another TU. */
3170 /* If the variable is internal, or if we can't generate aliases,
3171 call the local init function directly. */
3178 {
3181 void_list_node));
3190 {
3192 /* If the variable is defined somewhere else and might have static
3193 initialization, make the init function a weak reference. */
3199 else
3201 }
3211 }
3213 }
3215 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3216 variable VAR. The wrapper function calls the init function (if any) for
3217 VAR and then returns a reference to VAR. The wrapper function is used
3218 in place of VAR everywhere VAR is mentioned. */
3220 tree
3222 {
3223 /* Only C++11 TLS vars need this wrapper fn. */
3230 {
3231 /* A named rvalue reference is an lvalue, so the wrapper should
3232 always return an lvalue reference. */
3241 /* The wrapper is inline and emitted everywhere var is used. */
3244 {
3246 #ifdef HAVE_GAS_HIDDEN
3247 /* Make the wrapper bind locally; there's no reason to share
3248 the wrapper between multiple shared objects. */
3251 #endif
3252 }
3258 #if 0
3259 /* We want CSE to commonize calls to the wrapper, but marking it as
3260 pure is unsafe since it has side-effects. I guess we need a new
3261 ECF flag even weaker than ECF_PURE. FIXME! */
3263 #endif
3268 }
3270 }
3272 /* At EOF, generate the definition for the TLS wrapper function FN:
3274 T& var_wrapper() {
3275 if (init_fn) init_fn();
3276 return var;
3277 } */
3279 static void
3281 {
3286 /* Only call the init fn if there might be one. */
3288 {
3290 /* If init_fn is a weakref, make sure it exists before calling. */
3292 {
3297 tf_warning_or_error);
3299 }
3303 {
3306 }
3307 }
3308 else
3309 /* If there's no initialization, the wrapper is a constant function. */
3314 }
3316 /* Start the process of running a particular set of global constructors
3317 or destructors. Subroutine of do_[cd]tors. Also called from
3318 vtv_start_verification_constructor_init_function. */
3320 static tree
3322 {
3323 tree body;
3324 tree fndecl;
3327 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3330 {
3333 #ifdef JOINER
3335 #else
3337 #endif
3340 }
3341 else
3347 NULL_TREE));
3352 /* Mark as artificial because it's not explicitly in the user's
3353 source code. */
3356 /* Mark this declaration as used to avoid spurious warnings. */
3359 /* Mark this function as a global constructor or destructor. */
3362 else
3368 }
3370 /* Finish the process of running a particular set of global constructors
3371 or destructors. Subroutine of do_[cd]tors. */
3373 static void
3375 {
3376 tree fn;
3378 /* Finish up. */
3383 {
3386 }
3387 else
3388 {
3391 }
3394 }
3396 /* The names of the parameters to the function created to handle
3397 initializations and destructions for objects with static storage
3398 duration. */
3402 /* The name of the function we create to handle initializations and
3403 destructions for objects with static storage duration. */
3406 /* The declaration for the __INITIALIZE_P argument. */
3409 /* The declaration for the __PRIORITY argument. */
3412 /* The declaration for the static storage duration function. */
3415 /* All the static storage duration functions created in this
3416 translation unit. */
3419 /* A map from priority levels to information about that priority
3420 level. There may be many such levels, so efficient lookup is
3421 important. */
3424 /* Begins the generation of the function that will handle all
3425 initialization and destruction of objects with static storage
3426 duration. The function generated takes two parameters of type
3427 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3428 nonzero, it performs initializations. Otherwise, it performs
3429 destructions. It only performs those initializations or
3430 destructions with the indicated __PRIORITY. The generated function
3431 returns no value.
3433 It is assumed that this function will only be called once per
3434 translation unit. */
3436 static tree
3438 {
3439 tree type;
3440 tree body;
3443 /* Create the identifier for this function. It will be of the form
3444 SSDF_IDENTIFIER_<number>. */
3449 NULL_TREE);
3451 /* Create the FUNCTION_DECL itself. */
3454 type);
3458 /* Put this function in the list of functions to be called from the
3459 static constructors and destructors. */
3461 {
3464 /* Take this opportunity to initialize the map from priority
3465 numbers to information about that priority level. */
3468 /*delete_value_fn=*/
3471 /* We always need to generate functions for the
3472 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3473 priorities later, we'll be sure to find the
3474 DEFAULT_INIT_PRIORITY. */
3476 }
3480 /* Create the argument list. */
3481 initialize_p_decl = cp_build_parm_decl
3484 priority_decl = cp_build_parm_decl
3491 /* Put the function in the global scope. */
3494 /* Start the function itself. This is equivalent to declaring the
3495 function as:
3497 static void __ssdf (int __initialize_p, init __priority_p);
3499 It is static because we only need to call this function from the
3500 various constructor and destructor functions for this module. */
3503 SF_PRE_PARSED);
3505 /* Set up the scope of the outermost block in the function. */
3509 }
3511 /* Finish the generation of the function which performs initialization
3512 and destruction of objects with static storage duration. After
3513 this point, no more such objects can be created. */
3515 static void
3517 {
3518 /* Close out the function. */
3521 }
3523 /* Return the information about the indicated PRIORITY level. If no
3524 code to handle this level has yet been generated, generate the
3525 appropriate prologue. */
3527 static priority_info
3529 {
3530 priority_info pi;
3531 splay_tree_node n;
3536 {
3537 /* Create a new priority information structure, and insert it
3538 into the map. */
3545 }
3546 else
3550 }
3552 /* The effective initialization priority of a DECL. */
3554 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3555 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3556 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3558 /* Whether a DECL needs a guard to protect it against multiple
3559 initialization. */
3561 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3562 || DECL_ONE_ONLY (decl) \
3563 || DECL_WEAK (decl)))
3565 /* Called from one_static_initialization_or_destruction(),
3566 via walk_tree.
3567 Walks the initializer list of a global variable and looks for
3568 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3569 and that have their DECL_CONTEXT() == NULL.
3570 For each such temporary variable, set their DECL_CONTEXT() to
3571 the current function. This is necessary because otherwise
3572 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3573 when trying to refer to a temporary variable that does not have
3574 it's DECL_CONTECT() properly set. */
3575 static tree
3579 {
3583 {
3584 tree var;
3592 }
3595 }
3597 /* Set up to handle the initialization or destruction of DECL. If
3598 INITP is nonzero, we are initializing the variable. Otherwise, we
3599 are destroying it. */
3601 static void
3603 {
3605 tree guard;
3607 /* If we are supposed to destruct and there's a trivial destructor,
3608 nothing has to be done. */
3613 /* Trick the compiler into thinking we are at the file and line
3614 where DECL was declared so that error-messages make sense, and so
3615 that the debugger will show somewhat sensible file and line
3616 information. */
3619 /* Make sure temporary variables in the initialiser all have
3620 their DECL_CONTEXT() set to a value different from NULL_TREE.
3621 This can happen when global variables initializers are built.
3622 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3623 the temporary variables that might have been generated in the
3624 accompanying initializers is NULL_TREE, meaning the variables have been
3625 declared in the global namespace.
3626 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3627 of the temporaries are set to the current function decl. */
3629 fix_temporary_vars_context_r,
3630 NULL);
3632 /* Because of:
3634 [class.access.spec]
3636 Access control for implicit calls to the constructors,
3637 the conversion functions, or the destructor called to
3638 create and destroy a static data member is performed as
3639 if these calls appeared in the scope of the member's
3640 class.
3642 we pretend we are in a static member function of the class of
3643 which the DECL is a member. */
3645 {
3648 }
3650 /* Assume we don't need a guard. */
3652 /* We need a guard if this is an object with external linkage that
3653 might be initialized in more than one place. (For example, a
3654 static data member of a template, when the data member requires
3655 construction.) */
3657 {
3658 tree guard_cond;
3662 /* When using __cxa_atexit, we just check the GUARD as we would
3663 for a local static. */
3665 {
3666 /* When using __cxa_atexit, we never try to destroy
3667 anything from a static destructor. */
3670 }
3671 /* If we don't have __cxa_atexit, then we will be running
3672 destructors from .fini sections, or their equivalents. So,
3673 we need to know how many times we've tried to initialize this
3674 object. We do initializations only if the GUARD is zero,
3675 i.e., if we are the first to initialize the variable. We do
3676 destructions only if the GUARD is one, i.e., if we are the
3677 last to destroy the variable. */
3679 guard_cond
3681 EQ_EXPR,
3683 guard,
3685 tf_warning_or_error),
3686 integer_one_node,
3687 tf_warning_or_error);
3688 else
3689 guard_cond
3691 EQ_EXPR,
3693 guard,
3695 tf_warning_or_error),
3696 integer_zero_node,
3697 tf_warning_or_error);
3701 }
3704 /* If we're using __cxa_atexit, we have not already set the GUARD,
3705 so we must do so now. */
3709 /* Perform the initialization or destruction. */
3711 {
3713 {
3716 {
3720 }
3721 }
3723 /* If we're using __cxa_atexit, register a function that calls the
3724 destructor for the object. */
3727 }
3728 else
3731 /* Finish the guard if-stmt, if necessary. */
3733 {
3736 }
3738 /* Now that we're done with DECL we don't need to pretend to be a
3739 member of its class any longer. */
3742 }
3744 /* Generate code to do the initialization or destruction of the decls in VARS,
3745 a TREE_LIST of VAR_DECL with static storage duration.
3746 Whether initialization or destruction is performed is specified by INITP. */
3748 static void
3750 {
3753 /* Build the outer if-stmt to check for initialization or destruction. */
3757 EQ_EXPR,
3758 initialize_p_decl,
3759 cond,
3760 tf_warning_or_error);
3763 /* To make sure dynamic construction doesn't access globals from other
3764 compilation units where they might not be yet constructed, for
3765 -fsanitize=address insert __asan_before_dynamic_init call that
3766 prevents access to either all global variables that need construction
3767 in other compilation units, or at least those that haven't been
3768 initialized yet. Variables that need dynamic construction in
3769 the current compilation unit are kept accessible. */
3776 tree priority_if_stmt;
3778 priority_info pi;
3780 /* If we don't need a destructor, there's nothing to do. Avoid
3781 creating a possibly empty if-stmt. */
3783 {
3786 }
3788 /* Remember that we had an initialization or finalization at this
3789 priority. */
3794 else
3797 /* Conditionalize this initialization on being in the right priority
3798 and being initializing/finalizing appropriately. */
3801 EQ_EXPR,
3802 priority_decl,
3804 tf_warning_or_error);
3807 /* Process initializers with same priority. */
3811 /* Do one initialization or destruction. */
3815 /* Finish up the priority if-stmt body. */
3821 /* Revert what __asan_before_dynamic_init did by calling
3822 __asan_after_dynamic_init. */
3826 /* Finish up the init/destruct if-stmt body. */
3829 }
3831 /* VARS is a list of variables with static storage duration which may
3832 need initialization and/or finalization. Remove those variables
3833 that don't really need to be initialized or finalized, and return
3834 the resulting list. The order in which the variables appear in
3835 VARS is in reverse order of the order in which they should actually
3836 be initialized. The list we return is in the unreversed order;
3837 i.e., the first variable should be initialized first. */
3839 static tree
3841 {
3846 {
3851 /* Deal gracefully with error. */
3853 {
3856 }
3858 /* The only things that can be initialized are variables. */
3861 /* If this object is not defined, we don't need to do anything
3862 here. */
3864 {
3867 }
3869 /* Also, if the initializer already contains errors, we can bail
3870 out now. */
3873 {
3876 }
3878 /* This variable is going to need initialization and/or
3879 finalization, so we add it to the list. */
3883 }
3886 }
3888 /* Make sure we have told the back end about all the variables in
3889 VARS. */
3891 static void
3893 {
3894 tree v;
3897 {
3900 {
3903 }
3904 }
3905 }
3907 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
3908 (otherwise) that will initialize all global objects with static
3909 storage duration having the indicated PRIORITY. */
3911 static void
3914 {
3916 tree fndecl;
3917 tree body;
3921 /* ??? */
3922 /* Was: locus->line++; */
3924 /* We use `I' to indicate initialization and `D' to indicate
3925 destruction. */
3928 /* We emit the function lazily, to avoid generating empty
3929 global constructors and destructors. */
3932 /* For Objective-C++, we may need to initialize metadata found in this module.
3933 This must be done _before_ any other static initializations. */
3936 {
3939 }
3941 /* Call the static storage duration function with appropriate
3942 arguments. */
3944 {
3945 /* Calls to pure or const functions will expand to nothing. */
3947 {
3948 tree call;
3955 constructor_p),
3957 priority),
3958 NULL_TREE);
3960 }
3961 }
3963 /* Close out the function. */
3966 }
3968 /* Generate constructor and destructor functions for the priority
3969 indicated by N. */
3971 static int
3973 {
3978 /* Generate the functions themselves, but only if they are really
3979 needed. */
3985 /* Keep iterating. */
3987 }
3989 /* Return C++ property of T, based on given operation OP. */
3991 static int
3993 {
3995 {
3997 {
4005 }
4022 }
4023 }
4025 /* Collect source file references recursively, starting from NAMESPC. */
4027 static void
4029 {
4030 /* Iterate over names in this name space. */
4033 ;
4036 else
4038 }
4040 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4041 starting from NAMESPC. */
4043 static void
4045 {
4048 /* Collect decls from this namespace. This will skip
4049 NAMESPACE_DECLs (both aliases and regular, it cannot tell). */
4052 /* Now scan for namespace children, and dump them. */
4056 }
4058 /* Returns true iff there is a definition available for variable or
4059 function DECL. */
4061 bool
4063 {
4066 /* A pending instantiation of a friend temploid is defined. */
4070 else
4071 {
4074 }
4075 }
4077 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4079 [expr.const]
4081 An integral constant-expression can only involve ... const
4082 variables of integral or enumeration types initialized with
4083 constant expressions ...
4085 C++0x also allows constexpr variables and temporaries initialized
4086 with constant expressions. We handle the former here, but the latter
4087 are just folded away in cxx_eval_constant_expression.
4089 The standard does not require that the expression be non-volatile.
4090 G++ implements the proposed correction in DR 457. */
4092 bool
4094 {
4098 /* We don't know if a template static data member is initialized with
4099 a constant expression until we instantiate its initializer. Even
4100 in the case of a constexpr variable, we can't treat it as a
4101 constant until its initializer is complete in case it's used in
4102 its own initializer. */
4105 }
4107 /* Returns true if DECL could be a symbolic constant variable, depending on
4108 its initializer. */
4110 bool
4112 {
4119 /* A proxy isn't constant. */
4126 else
4131 /* We know the initializer, and it isn't constant. */
4133 else
4135 }
4137 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4138 called from grokfndecl and grokvardecl; in all modes it is called from
4139 cp_write_global_declarations. */
4141 void
4143 {
4145 /* In C++11 it's ok if the decl is defined. */
4149 /* The type that got us on no_linkage_decls must have gotten a name for
4152 /* The type might end up having a typedef name for linkage purposes. */
4155 {
4163 /* DRs 132, 319 and 389 seem to indicate types with
4164 no linkage can only be used to declare extern "C"
4165 entities. Since it's not always an error in the
4166 ISO C++ 90 Standard, we only issue a warning. */
4168 "with no linkage used to declare variable %q#D with "
4170 else
4173 decl);
4178 }
4180 {
4183 "%q#D, declared using local type "
4185 }
4189 else
4192 }
4194 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4196 static void
4198 {
4200 }
4202 /* Clear DECL_EXTERNAL for NODE. */
4204 static bool
4206 {
4209 }
4211 /* Build up the function to run dynamic initializers for thread_local
4212 variables in this translation unit and alias the init functions for the
4213 individual variables to it. */
4215 static void
4217 {
4227 boolean_type_node);
4242 tf_warning_or_error);
4245 boolean_true_node,
4246 tf_warning_or_error));
4248 {
4253 /* Output init aliases even with -fno-extern-tls-init. */
4255 {
4259 cgraph_node *alias
4263 }
4264 }
4270 }
4272 /* We're at the end of compilation, so generate any mangling aliases that
4273 we've been saving up, if DECL is going to be output and ID2 isn't
4274 already taken by another declaration. */
4276 static void
4278 {
4279 /* If there's a declaration already using this mangled name,
4280 don't create a compatibility alias that conflicts. */
4287 /* Don't create an alias to an unreferenced function. */
4299 else
4301 }
4303 /* Note that we might want to emit an alias with the symbol ID2 for DECL at
4304 the end of translation, for compatibility across bugs in the mangling
4305 implementation. */
4307 void
4309 {
4311 {
4314 else
4315 {
4318 }
4319 }
4320 }
4322 /* Emit all mangling aliases that were deferred up to this point. */
4324 void
4326 {
4328 {
4332 }
4334 }
4336 /* The entire file is now complete. If requested, dump everything
4337 to a file. */
4339 static void
4341 {
4342 dump_flags_t flags;
4344 {
4347 }
4348 }
4352 /* Check the deallocation functions for CODE to see if we want to warn that
4353 only one was defined. */
4355 static void
4357 {
4363 {
4365 /* We're only interested in usual deallocation functions. */
4370 else
4372 }
4379 }
4381 /* Check the global deallocation functions to see if we want to warn about
4382 defining unsized without sized (or vice versa). */
4384 static void
4386 {
4391 }
4393 /* Earlier we left PTRMEM_CST in variable initializers alone so that we could
4394 look them up when evaluating non-type template parameters. Now we need to
4395 lower them to something the back end can understand. */
4397 static void
4399 {
4402 {
4406 }
4407 }
4409 /* This routine is called at the end of compilation.
4410 Its job is to create all the code needed to initialize and
4411 destroy the global aggregates. We do the destruction
4412 first, since that way we only need to reverse the decls once. */
4414 void
4416 {
4417 tree vars;
4422 tree decl;
4427 /* Bad parse errors. Just forget about it. */
4432 /* This is the point to write out a PCH if we're doing that.
4433 In that case we do not want to do anything else. */
4435 {
4436 /* Mangle all symbols at PCH creation time. */
4444 /* Ensure even the callers don't try to finalize the CU. */
4447 }
4454 /* Handle -fdump-ada-spec[-slim] */
4456 {
4459 else
4463 }
4465 /* FIXME - huh? was input_line -= 1;*/
4467 /* We now have to write out all the stuff we put off writing out.
4468 These include:
4470 o Template specializations that we have not yet instantiated,
4471 but which are needed.
4472 o Initialization and destruction for non-local objects with
4473 static storage duration. (Local objects with static storage
4474 duration are initialized when their scope is first entered,
4475 and are cleaned up via atexit.)
4476 o Virtual function tables.
4478 All of these may cause others to be needed. For example,
4479 instantiating one function may cause another to be needed, and
4480 generating the initializer for an object may cause templates to be
4481 instantiated, etc., etc. */
4485 do
4486 {
4487 tree t;
4488 tree decl;
4492 /* If there are templates that we've put off instantiating, do
4493 them now. */
4497 /* Write out virtual tables as required. Writing out the
4498 virtual table for a template class may cause the
4499 instantiation of members of that class. If we write out
4500 vtables then we remove the class from our list so we don't
4501 have to look at it again. */
4505 {
4508 }
4510 /* Write out needed type info variables. We have to be careful
4511 looping through unemitted decls, because emit_tinfo_decl may
4512 cause other variables to be needed. New elements will be
4513 appended, and we remove from the vector those that actually
4514 get emitted. */
4518 {
4521 }
4523 /* The list of objects with static storage duration is built up
4524 in reverse order. We clear STATIC_AGGREGATES so that any new
4525 aggregates added during the initialization of these will be
4526 initialized in the correct order when we next come around the
4527 loop. */
4531 {
4532 /* We need to start a new initialization function each time
4533 through the loop. That's because we need to know which
4534 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4535 isn't computed until a function is finished, and written
4536 out. That's a deficiency in the back end. When this is
4537 fixed, these initialization functions could all become
4538 inline, with resulting performance improvements. */
4539 tree ssdf_body;
4541 /* Set the line and file, so that it is obviously not from
4542 the source file. */
4546 /* Make sure the back end knows about all the variables. */
4549 /* First generate code to do all the initializations. */
4553 /* Then, generate code to do all the destructions. Do these
4554 in reverse order so that the most recently constructed
4555 variable is the first destroyed. If we're using
4556 __cxa_atexit, then we don't need to do this; functions
4557 were registered at initialization time to destroy the
4558 local statics. */
4560 {
4563 }
4564 else
4567 /* Finish up the static storage duration function for this
4568 round. */
4572 /* All those initializations and finalizations might cause
4573 us to need more inline functions, more template
4574 instantiations, etc. */
4576 ssdf_count++;
4577 /* ??? was: locus_at_end_of_parsing.line++; */
4578 }
4580 /* Now do the same for thread_local variables. */
4583 /* Go through the set of inline functions whose bodies have not
4584 been emitted yet. If out-of-line copies of these functions
4585 are required, emit them. */
4587 {
4588 /* Does it need synthesizing? */
4591 {
4592 /* Even though we're already at the top-level, we push
4593 there again. That way, when we pop back a few lines
4594 hence, all of our state is restored. Otherwise,
4595 finish_function doesn't clean things up, and we end
4596 up with CURRENT_FUNCTION_DECL set. */
4598 /* The decl's location will mark where it was first
4599 needed. Save that so synthesize method can indicate
4600 where it was needed from, in case of error */
4605 }
4615 /* We lie to the back end, pretending that some functions
4616 are not defined when they really are. This keeps these
4617 functions from being put out unnecessarily. But, we must
4618 stop lying when the functions are referenced, or if they
4619 are not comdat since they need to be put out now. If
4620 DECL_INTERFACE_KNOWN, then we have already set
4621 DECL_EXTERNAL appropriately, so there's no need to check
4622 again, and we do not want to clear DECL_EXTERNAL if a
4623 previous call to import_export_decl set it.
4625 This is done in a separate for cycle, because if some
4626 deferred function is contained in another deferred
4627 function later in deferred_fns varray,
4628 rest_of_compilation would skip this function and we
4629 really cannot expand the same function twice. */
4634 {
4640 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4641 group, we need to mark all symbols in the same comdat group
4642 that way. */
4650 }
4652 /* If we're going to need to write this function out, and
4653 there's already a body for it, create RTL for it now.
4654 (There might be no body if this is a method we haven't
4655 gotten around to synthesizing yet.) */
4660 {
4661 /* We will output the function; no longer consider it in this
4662 loop. */
4664 /* Generate RTL for this function now that we know we
4665 need it. */
4667 /* If we're compiling -fsyntax-only pretend that this
4668 function has been written out so that we don't try to
4669 expand it again. */
4673 }
4674 }
4679 /* Static data members are just like namespace-scope globals. */
4681 {
4683 /* Don't write it out if we haven't seen a definition. */
4687 /* If this static data member is needed, provide it to the
4688 back end. */
4691 }
4697 retries++;
4698 }
4705 /* All used inline functions must have a definition at this point. */
4707 {
4710 /* If the definition actually was available here, then the
4711 fact that the function was not defined merely represents
4712 that for some reason (use of a template repository,
4713 #pragma interface, etc.) we decided not to emit the
4714 definition here. */
4716 /* Don't complain if the template was defined. */
4720 {
4723 /* Avoid a duplicate warning from check_global_declaration. */
4725 }
4726 }
4728 /* So must decls that use a type with no linkage. */
4734 /* Then, do the Objective-C stuff. This is where all the
4735 Objective-C module stuff gets generated (symtab,
4736 class/protocol/selector lists etc). This must be done after C++
4737 templates, destructors etc. so that selectors used in C++
4738 templates are properly allocated. */
4742 /* We give C linkage to static constructors and destructors. */
4745 /* Generate initialization and destruction functions for all
4746 priorities for which they are required. */
4749 generate_ctor_and_dtor_functions_for_priority,
4752 /* If this is obj-c++ and we need a static init, call
4753 generate_ctor_or_dtor_function. */
4755 DEFAULT_INIT_PRIORITY,
4758 /* We're done with the splay-tree now. */
4762 /* Generate any missing aliases. */
4765 /* We're done with static constructors, so we can go back to "C++"
4766 linkage now. */
4770 {
4774 }
4781 /* The entire file is now complete. If requested, dump everything
4782 to a file. */
4786 {
4789 }
4794 /* Indicate that we're done with front end processing. */
4796 }
4798 /* Perform any post compilation-proper cleanups for the C++ front-end.
4799 This should really go away. No front-end should need to do
4800 anything past the compilation process. */
4802 void
4804 {
4808 {
4809 /* Generate the special constructor initialization function that
4810 calls __VLTRegisterPairs, and give it a very high
4811 initialization priority. This must be done after
4812 finalize_compilation_unit so that we have accurate
4813 information about which vtable will actually be emitted. */
4815 }
4823 }
4825 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
4826 function to call in parse-tree form; it has not yet been
4827 semantically analyzed. ARGS are the arguments to the function.
4828 They have already been semantically analyzed. This may change
4829 ARGS. */
4831 tree
4833 tsubst_flags_t complain)
4834 {
4835 tree orig_fn;
4837 tree expr;
4838 tree object;
4844 {
4853 /* Transform the arguments and add the implicit "this"
4854 parameter. That must be done before the FN is transformed
4855 because we depend on the form of FN. */
4859 {
4863 }
4864 /* Now that the arguments are done, transform FN. */
4866 }
4868 /* A qualified name corresponding to a bound pointer-to-member is
4869 represented as an OFFSET_REF:
4871 struct B { void g(); };
4872 void (B::*p)();
4873 void B::g() { (this->*p)(); } */
4875 {
4879 complain);
4881 }
4885 else
4894 }
4897 void
4899 {
4904 {
4908 {
4911 }
4912 }
4913 }
4915 /* Return true if function DECL can be inlined. This is used to force
4916 instantiation of methods that might be interesting for inlining. */
4917 bool
4919 {
4925 /* When optimizing, we might inline everything when flatten
4926 attribute or heuristics inlining for size or autoinlining
4927 is used. */
4929 }
4931 /* Normally, we can wait until instantiation-time to synthesize DECL.
4932 However, if DECL is a static data member initialized with a constant
4933 or a constexpr function, we need it right now because a reference to
4934 such a data member or a call to such function is not value-dependent.
4935 For a function that uses auto in the return type, we need to instantiate
4936 it to find out its type. For OpenMP user defined reductions, we need
4937 them instantiated for reduction clauses which inline them by hand
4938 directly. */
4940 static void
4942 {
4951 {
4952 /* Instantiating a function will result in garbage collection. We
4953 must treat this situation as if we were within the body of a
4954 function so as to avoid collecting live data only referenced from
4955 the stack (such as overload resolution candidates). */
4960 }
4961 }
4963 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
4964 If DECL is a specialization or implicitly declared class member,
4965 generate the actual definition. Return false if something goes
4966 wrong, true otherwise. */
4968 bool
4970 {
4971 /* If DECL is a BASELINK for a single function, then treat it just
4972 like the DECL for the function. Otherwise, if the BASELINK is
4973 for an overloaded function, we don't know which function was
4974 actually used until after overload resolution. */
4976 {
4981 }
4983 /* Set TREE_USED for the benefit of -Wunused. */
4985 /* And for structured bindings also the underlying decl. */
4995 /* Mark enumeration types as used. */
5005 {
5009 /* We mark a lambda conversion op as deleted if we can't
5010 generate it properly; see maybe_add_lambda_conv_op. */
5013 {
5017 }
5019 }
5025 /* We can only check DECL_ODR_USED on variables or functions with
5026 DECL_LANG_SPECIFIC set, and these are also the only decls that we
5027 might need special handling for. */
5031 {
5036 }
5038 /* We only want to do this processing once. We don't need to keep trying
5039 to instantiate inline templates, because unit-at-a-time will make sure
5040 we get them compiled before functions that want to inline them. */
5044 /* Normally, we can wait until instantiation-time to synthesize DECL.
5045 However, if DECL is a static data member initialized with a constant
5046 or a constexpr function, we need it right now because a reference to
5047 such a data member or a call to such function is not value-dependent.
5048 For a function that uses auto in the return type, we need to instantiate
5049 it to find out its type. For OpenMP user defined reductions, we need
5050 them instantiated for reduction clauses which inline them by hand
5051 directly. */
5057 /* Check this too in case we're within instantiate_non_dependent_expr. */
5066 {
5070 }
5072 /* If we don't need a value, then we don't need to synthesize DECL. */
5080 /* DR 757: A type without linkage shall not be used as the type of a
5081 variable or function with linkage, unless
5082 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5083 o the variable or function is not used (3.2 [basic.def.odr]) or is
5084 defined in the same translation unit. */
5091 {
5093 /* There's no way to define a local extern, and adding it to
5094 the vector interferes with GC, so give an error now. */
5096 else
5098 }
5102 /* Remember it, so we can check it was defined. */
5105 /* Is it a synthesized method that needs to be synthesized? */
5109 /* A function defaulted outside the class is synthesized either by
5110 cp_finish_decl or instantiate_decl. */
5113 {
5114 /* Defer virtual destructors so that thunks get the right
5115 linkage. */
5117 {
5120 }
5122 /* Remember the current location for a function we will end up
5123 synthesizing. Then we can inform the user where it was
5124 required in the case of error. */
5127 /* Synthesizing an implicitly defined member function will result in
5128 garbage collection. We must treat this situation as if we were
5129 within the body of a function so as to avoid collecting live data
5130 on the stack (such as overload resolution candidates).
5132 We could just let cp_write_global_declarations handle synthesizing
5133 this function by adding it to deferred_fns, but doing
5134 it at the use site produces better error messages. */
5138 /* If this is a synthesized method we don't need to
5139 do the instantiation test below. */
5140 }
5146 /* If this is a function or variable that is an instance of some
5147 template, we now know that we will need to actually do the
5148 instantiation. We check that DECL is not an explicit
5149 instantiation because that is not checked in instantiate_decl.
5151 We put off instantiating functions in order to improve compile
5152 times. Maintaining a stack of active functions is expensive,
5153 and the inliner knows to instantiate any functions it might
5154 need. Therefore, we always try to defer instantiation. */
5155 {
5160 }
5163 }
5165 bool
5167 {
5169 }
5171 tree
5173 {
5175 }
5177 tree
5179 {
5180 tree fn;
5188 }