| blob | 4478c6cb15cd0e770d42fb51684d52f3b86b25bc |
1 /* Process declarations and variables for C++ compiler.
2 Copyright (C) 1988-2014 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. */
71 /* This structure contains information about the initializations
72 and/or destructions required for a particular priority level. */
74 /* Nonzero if there have been any initializations at this priority
75 throughout the translation unit. */
77 /* Nonzero if there have been any destructions at this priority
78 throughout the translation unit. */
103 /* A list of static class variables. This is needed, because a
104 static class variable can be declared inside the class without
105 an initializer, and then initialized, statically, outside the class. */
108 /* A list of functions which were declared inline, but which we
109 may need to emit outline anyway. */
112 /* A list of decls that use types with no linkage, which we need to make
113 sure are defined. */
116 /* Nonzero if we're done parsing and into end-of-file activities. */
119 \f
121 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a
122 FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers
123 that apply to the function). */
125 tree
127 cp_ref_qualifier rqual)
128 {
129 tree raises;
130 tree attrs;
159 }
161 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its
162 return type changed to NEW_RET. */
164 tree
166 {
167 tree newtype;
180 {
185 }
186 else
187 newtype = build_method_type_directly
197 }
199 /* Build a PARM_DECL with NAME and TYPE, and set DECL_ARG_TYPE
200 appropriately. */
202 tree
204 {
207 /* DECL_ARG_TYPE is only used by the back end and the back end never
208 sees templates. */
213 }
215 /* Returns a PARM_DECL for a parameter of the indicated TYPE, with the
216 indicated NAME. */
218 tree
220 {
223 /* All our artificial parms are implicitly `const'; they cannot be
224 assigned to. */
227 }
229 /* Constructors for types with virtual baseclasses need an "in-charge" flag
230 saying whether this constructor is responsible for initialization of
231 virtual baseclasses or not. All destructors also need this "in-charge"
232 flag, which additionally determines whether or not the destructor should
233 free the memory for the object.
235 This function adds the "in-charge" flag to member function FN if
236 appropriate. It is called from grokclassfn and tsubst.
237 FN must be either a constructor or destructor.
239 The in-charge flag follows the 'this' parameter, and is followed by the
240 VTT parm (if any), then the user-written parms. */
242 void
244 {
247 /* If we've already add the in-charge parameter don't do it again. */
251 /* When processing templates we can't know, in general, whether or
252 not we're going to have virtual baseclasses. */
256 /* We don't need an in-charge parameter for constructors that don't
257 have virtual bases. */
268 /* If this is a subobject constructor or destructor, our caller will
269 pass us a pointer to our VTT. */
271 {
274 /* First add it to DECL_ARGUMENTS between 'this' and the real args... */
278 /* ...and then to TYPE_ARG_TYPES. */
282 }
284 /* Then add the in-charge parm (before the VTT parm). */
290 /* Insert our new parameter(s) into the list. */
293 /* And rebuild the function type. */
295 arg_types);
300 fntype = (cp_build_type_attribute_variant
304 /* Now we've got the in-charge parameter. */
306 }
308 /* Classes overload their constituent function names automatically.
309 When a function name is declared in a record structure,
310 its name is changed to it overloaded name. Since names for
311 constructors and destructors can conflict, we place a leading
312 '$' for destructors.
314 CNAME is the name of the class we are grokking for.
316 FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'.
318 FLAGS contains bits saying what's special about today's
319 arguments. DTOR_FLAG == DESTRUCTOR.
321 If FUNCTION is a destructor, then we must add the `auto-delete' field
322 as a second parameter. There is some hair associated with the fact
323 that we must "declare" this variable in the manner consistent with the
324 way the rest of the arguments were declared.
326 QUALS are the qualifiers for the this pointer. */
328 void
330 {
333 /* Even within an `extern "C"' block, members get C++ linkage. See
334 [dcl.link] for details. */
338 {
342 }
351 }
353 /* Create an ARRAY_REF, checking for the user doing things backwards
354 along the way. DECLTYPE_P is for N3276, as in the parser. */
356 tree
359 {
360 tree type;
361 tree expr;
369 {
376 }
382 /* If they have an `operator[]', use that. */
384 {
390 }
391 else
392 {
395 /* Otherwise, create an ARRAY_REF for a pointer or array type.
396 It is a little-known fact that, if `a' is an array and `i' is
397 an int, you can write `i[a]', which means the same thing as
398 `a[i]'. */
401 else
406 else
421 else
422 {
426 }
432 }
437 }
439 /* Given the cast expression EXP, checking out its validity. Either return
440 an error_mark_node if there was an unavoidable error, return a cast to
441 void for trying to delete a pointer w/ the value 0, or return the
442 call to delete. If DOING_VEC is true, we handle things differently
443 for doing an array delete.
444 Implements ARM $5.3.4. This is called from the parser. */
446 tree
448 tsubst_flags_t complain)
449 {
456 {
462 }
464 /* An array can't have been allocated by new, so complain. */
471 {
475 }
479 /* As of Valley Forge, you can delete a pointer to const. */
481 /* You can't delete functions. */
483 {
487 }
489 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */
491 {
494 }
496 /* Deleting a pointer with the value zero is valid and has no effect. */
502 sfk_deleting_destructor,
504 else
507 complain);
508 }
510 /* Report an error if the indicated template declaration is not the
511 sort of thing that should be a member template. */
513 void
515 {
516 tree decl;
525 {
526 /* The parser rejects template declarations in local classes
527 (with the exception of generic lambdas). */
529 /* The parser rejects any use of virtual in a function template. */
533 /* The debug-information generating code doesn't know what to do
534 with member templates. */
536 }
539 else
541 }
543 /* Return true iff TYPE is a valid Java parameter or return type. */
545 static bool
547 {
554 {
557 {
566 {
572 }
574 }
575 }
577 }
579 /* For a METHOD in a Java class CTYPE, return true if
580 the parameter and return types are valid Java types.
581 Otherwise, print appropriate error messages, and return false. */
583 bool
585 {
591 {
595 }
604 {
607 {
612 }
613 }
615 }
617 /* Sanity check: report error if this function FUNCTION is not
618 really a member of the class (CTYPE) it is supposed to belong to.
619 TEMPLATE_PARMS is used to specify the template parameters of a member
620 template passed as FUNCTION_DECL. If the member template is passed as a
621 TEMPLATE_DECL, it can be NULL since the parameters can be extracted
622 from the declaration. If the function is not a function template, it
623 must be NULL.
624 It returns the original declaration for the function, NULL_TREE if
625 no declaration was found, error_mark_node if an error was emitted. */
627 tree
629 {
632 tree pushed_scope;
638 /* Since this is a specialization of a member template,
639 we're not going to find the declaration in the class.
640 For example, in:
642 struct S { template <typename T> void f(T); };
643 template <> void S::f(int);
645 we're not going to find `S::f(int)', but there's no
646 reason we should, either. We let our callers know we didn't
647 find the method, but we don't complain. */
650 /* Basic sanity check: for a template function, the template parameters
651 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */
653 {
657 {
661 }
663 }
665 /* OK, is this a definition of a member template? */
668 /* [temp.mem]
670 A destructor shall not be a member template. */
672 {
675 }
677 /* We must enter the scope here, because conversion operators are
678 named by target type, and type equivalence relies on typenames
679 resolving within the scope of CTYPE. */
683 {
691 {
698 /* We cannot simply call decls_match because this doesn't
699 work for static member functions that are pretending to
700 be methods, and because the name may have been changed by
701 asm("new_name"). */
703 /* Get rid of the this parameter on functions that become
704 static. */
709 /* A member template definition only matches a member template
710 declaration. */
714 /* ref-qualifier or absence of same must match. */
719 /* While finding a match, same types and params are not enough
720 if the function is versioned. Also check version ("target")
721 attributes. */
726 && (!is_template
735 }
737 {
741 }
752 {
757 {
759 {
762 {
765 }
766 }
767 else
769 }
774 else
777 }
778 }
781 else
788 }
790 /* DECL is a function with vague linkage. Remember it so that at the
791 end of the translation unit we can decide whether or not to emit
792 it. */
794 void
796 {
799 }
801 /* As above, but for variable template instantiations. */
803 void
805 {
807 }
809 /* We have just processed the DECL, which is a static data member.
810 The other parameters are as for cp_finish_decl. */
812 void
815 tree asmspec_tree,
817 {
820 /* We cannot call pushdecl here, because that would fill in the
821 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do
822 the right thing, namely, to put this decl out straight away. */
828 /* We already complained about the template definition. */
832 else
836 {
842 }
851 }
853 /* DECLARATOR and DECLSPECS correspond to a class member. The other
854 parameters are as for cp_finish_decl. Return the DECL for the
855 class member declared. */
857 tree
861 tree asmspec_tree,
862 tree attrlist)
863 {
864 tree value;
867 tree name;
877 /* friend or constructor went bad. */
883 {
886 }
888 /* Pass friendly classes back. */
896 {
898 {
901 }
906 value);
907 }
909 /* Stash away type declarations. */
911 {
916 {
919 /* If this is a typedef that names the class for linkage purposes
920 (7.1.3p8), apply any attributes directly to the type. */
926 }
933 /* It's important that push_template_decl below follows
934 set_underlying_type above so that the created template
935 carries the properly set type of VALUE. */
941 }
946 {
949 }
955 {
957 {
959 {
963 }
965 {
967 {
971 }
972 }
976 {
981 else
983 value);
984 }
985 else
986 {
990 value);
991 else
993 value);
994 }
995 }
1000 }
1002 /* Pass friend decls back. */
1008 /* Need to set this before push_template_decl. */
1013 {
1017 }
1024 else
1028 {
1053 /* Pass friends back this way. */
1062 }
1064 }
1066 /* Like `grokfield', but for bitfields.
1067 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */
1069 tree
1072 tree attrlist)
1073 {
1081 /* Pass friendly classes back. */
1088 {
1091 }
1094 {
1097 }
1099 /* Usually, finish_struct_1 catches bitfields with invalid types.
1100 But, in the case of bitfields with function type, we confuse
1101 ourselves into thinking they are member functions, so we must
1102 check here. */
1104 {
1108 }
1111 {
1115 }
1118 {
1121 }
1125 {
1126 /* The width must be an integer type. */
1133 }
1141 }
1143 \f
1144 /* Returns true iff ATTR is an attribute which needs to be applied at
1145 instantiation time rather than template definition time. */
1147 static bool
1149 {
1153 tree arg;
1156 /* Unknown attribute. */
1159 /* Attribute weak handling wants to write out assembly right away. */
1163 /* Attribute unused is applied directly, as it appertains to
1164 decls. */
1168 /* #pragma omp declare simd attribute needs to be always deferred. */
1173 /* If any of the arguments are dependent expressions, we can't evaluate
1174 the attribute until instantiation time. */
1176 {
1179 /* If the first attribute argument is an identifier, only consider
1180 second and following arguments. Attributes like mode, format,
1181 cleanup and several target specific attributes aren't late
1182 just because they have an IDENTIFIER_NODE as first argument. */
1189 }
1194 {
1197 /* We can't apply any attributes to a completely unknown type until
1198 instantiation time. */
1204 /* Also defer most attributes on dependent types. This is not
1205 necessary in all cases, but is the better default. */
1207 /* But some attributes specifically apply to templates. */
1212 else
1214 }
1215 else
1217 }
1219 /* ATTR_P is a list of attributes. Remove any attributes which need to be
1220 applied at instantiation time and return them. If IS_DEPENDENT is true,
1221 the declaration itself is dependent, so all attributes should be applied
1222 at instantiation time. */
1224 static tree
1226 {
1235 {
1237 {
1243 }
1244 else
1246 }
1249 }
1251 /* Remove any late attributes from the list in ATTR_P and attach them to
1252 DECL_P. */
1254 static void
1256 {
1268 else
1273 /* Merge the late attributes at the beginning with the attribute
1274 list. */
1279 {
1280 /* We've added new attributes directly to the main variant, so
1281 now we need to update all of the other variants to include
1282 these new attributes. */
1283 tree variant;
1286 {
1289 }
1290 }
1291 }
1293 /* Return true iff ATTRS are acceptable attributes to be applied in-place
1294 to a typedef which gives a previously anonymous class or enum a name for
1295 linkage purposes. */
1297 bool
1299 {
1301 {
1305 }
1307 }
1309 /* Like reconstruct_complex_type, but handle also template trees. */
1311 tree
1313 {
1318 {
1322 }
1324 {
1328 }
1330 {
1333 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the
1334 element type qualification will be handled by the recursive
1335 cp_reconstruct_complex_type call and cp_build_qualified_type
1336 for ARRAY_TYPEs changes the element type. */
1338 }
1340 {
1347 }
1349 {
1352 /* The build_method_type_directly() routine prepends 'this' to argument list,
1353 so we must compensate by getting rid of it. */
1354 outer
1355 = build_method_type_directly
1358 }
1360 {
1363 }
1364 else
1375 }
1377 /* Replaces any constexpr expression that may be into the attributes
1378 arguments with their reduced value. */
1380 static void
1382 {
1386 tree attr;
1388 {
1389 tree arg;
1391 {
1395 }
1396 }
1397 }
1399 /* Return true if TYPE is an OpenMP mappable type. */
1400 bool
1402 {
1403 /* Mappable type has to be complete. */
1406 /* Arrays have mappable type if the elements have mappable type. */
1409 /* A mappable type cannot contain virtual members. */
1412 /* All data members must be non-static. */
1414 {
1415 tree field;
1419 /* All fields must have mappable types. */
1423 }
1425 }
1427 /* Like decl_attributes, but handle C++ complexity. */
1429 void
1431 {
1436 /* Add implicit "omp declare target" attribute if requested. */
1440 {
1455 else
1458 }
1461 {
1466 }
1474 {
1476 attributes
1478 else
1479 attributes
1483 }
1484 else
1487 else
1493 /* Propagate deprecation out to the template. */
1496 {
1502 }
1503 }
1504 \f
1505 /* Walks through the namespace- or function-scope anonymous union
1506 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1507 Returns one of the fields for use in the mangled name. */
1509 static tree
1511 {
1513 tree field;
1515 /* Rather than write the code to handle the non-union case,
1516 just give an error. */
1518 {
1521 }
1526 {
1527 tree decl;
1528 tree ref;
1533 {
1537 }
1547 else
1552 {
1553 tree base;
1569 }
1572 else
1577 }
1580 }
1582 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1583 anonymous union, then all members must be laid out together. PUBLIC_P
1584 is nonzero if this union is not declared static. */
1586 void
1588 {
1589 tree type;
1590 tree main_decl;
1599 /* The VAR_DECL's context is the same as the TYPE's context. */
1606 {
1609 }
1615 {
1618 }
1621 {
1622 /* Use main_decl to set the mangled name. */
1628 }
1632 }
1633 \f
1634 /* Auxiliary functions to make type signatures for
1635 `operator new' and `operator delete' correspond to
1636 what compiler will be expecting. */
1638 tree
1640 {
1647 {
1650 }
1653 {
1655 {
1656 /* [basic.stc.dynamic.allocation]
1658 The first parameter shall not have an associated default
1659 argument. */
1662 /* Throw away the default argument. */
1664 }
1667 {
1670 }
1671 }
1672 else
1680 {
1683 /* Fall through. */
1685 type = build_exception_variant
1688 /* Fall through. */
1690 }
1692 }
1694 tree
1696 {
1703 {
1706 }
1710 {
1715 ptr_type_node);
1716 }
1718 {
1721 /* Fall through. */
1723 type = build_exception_variant
1726 /* Fall through. */
1728 }
1731 }
1732 \f
1733 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1734 and mark them as needed. */
1736 static void
1738 {
1739 tree fnaddr;
1744 {
1745 tree fn;
1751 /* This entry is an offset: a virtual base class offset, a
1752 virtual call offset, an RTTI offset, etc. */
1757 /* When we don't have vcall offsets, we output thunks whenever
1758 we output the vtables that contain them. With vcall offsets,
1759 we know all the thunks we'll need when we emit a virtual
1760 function, so we emit the thunks there instead. */
1764 }
1765 }
1767 /* Set DECL up to have the closest approximation of "initialized common"
1768 linkage available. */
1770 void
1772 {
1777 /* We can just emit function and compiler-generated variables
1778 statically; having multiple copies is (for the most part) only
1779 a waste of space.
1781 There are two correctness issues, however: the address of a
1782 template instantiation with external linkage should be the
1783 same, independent of what translation unit asks for the
1784 address, and this will not hold when we emit multiple copies of
1785 the function. However, there's little else we can do.
1787 Also, by default, the typeinfo implementation assumes that
1788 there will be only one copy of the string used as the name for
1789 each type. Therefore, if weak symbols are unavailable, the
1790 run-time library should perform a more conservative check; it
1791 should perform a string comparison, rather than an address
1792 comparison. */
1794 else
1795 {
1796 /* Static data member template instantiations, however, cannot
1797 have multiple copies. */
1802 {
1805 }
1807 {
1808 /* We can't do anything useful; leave vars for explicit
1809 instantiation. */
1812 }
1813 }
1816 }
1818 /* For win32 we also want to put explicit instantiations in
1819 linkonce sections, so that they will be merged with implicit
1820 instantiations; otherwise we get duplicate symbol errors.
1821 For Darwin we do not want explicit instantiations to be
1822 linkonce. */
1824 void
1826 {
1827 /* We used to say that this was not necessary on targets that support weak
1828 symbols, because the implicit instantiations will defer to the explicit
1829 one. However, that's not actually the case in SVR4; a strong definition
1830 after a weak one is an error. Also, not making explicit
1831 instantiations one_only means that we can end up with two copies of
1832 some template instantiations. */
1836 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1837 we can get away with not emitting them if they aren't used. We need
1838 to for variables so that cp_finish_decl will update their linkage,
1839 because their DECL_INITIAL may not have been set properly yet. */
1844 {
1848 {
1851 /* Mark it needed so we don't forget to emit it. */
1854 }
1855 }
1856 }
1858 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1859 This predicate will give the right answer during parsing of the
1860 function, which other tests may not. */
1862 bool
1864 {
1865 /* Unfortunately, import_export_decl has not always been called
1866 before the function is processed, so we cannot simply check
1867 DECL_COMDAT. */
1876 /* A local static in an inline effectively has vague linkage. */
1879 else
1881 }
1883 /* Determine whether or not we want to specifically import or export CTYPE,
1884 using various heuristics. */
1886 static void
1888 {
1889 /* -1 for imported, 1 for exported. */
1892 /* It only makes sense to call this function at EOF. The reason is
1893 that this function looks at whether or not the first non-inline
1894 non-abstract virtual member function has been defined in this
1895 translation unit. But, we can't possibly know that until we've
1896 seen the entire translation unit. */
1902 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1903 we will have CLASSTYPE_INTERFACE_ONLY set but not
1904 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1905 heuristic because someone will supply a #pragma implementation
1906 elsewhere, and deducing it here would produce a conflict. */
1916 /* For a template class, without -fimplicit-templates, check the
1917 repository. If the virtual table is assigned to this
1918 translation unit, then export the class; otherwise, import
1919 it. */
1922 {
1923 /* The ABI specifies that the virtual table and associated
1924 information are emitted with the key method, if any. */
1926 /* If weak symbol support is not available, then we must be
1927 careful not to emit the vtable when the key function is
1928 inline. An inline function can be defined in multiple
1929 translation units. If we were to emit the vtable in each
1930 translation unit containing a definition, we would get
1931 multiple definition errors at link-time. */
1934 }
1936 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1937 a definition anywhere else. */
1941 /* Allow back ends the chance to overrule the decision. */
1946 {
1949 }
1950 }
1952 /* Return true if VAR has already been provided to the back end; in that
1953 case VAR should not be modified further by the front end. */
1954 static bool
1956 {
1958 }
1960 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1961 must be emitted in this translation unit. Mark it as such. */
1963 void
1965 {
1968 {
1969 /* Extern inline functions don't become needed when referenced.
1970 If we know a method will be emitted in other TU and no new
1971 functions can be marked reachable, just use the external
1972 definition. */
1976 /* #pragma interface and -frepo code can call mark_needed for
1977 maybe-in-charge 'tors; mark the clones as well. */
1978 tree clone;
1981 }
1983 {
1985 /* C++ frontend use mark_decl_references to force COMDAT variables
1986 to be output that might appear dead otherwise. */
1988 }
1989 }
1991 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
1992 returns true if a definition of this entity should be provided in
1993 this object file. Callers use this function to determine whether
1994 or not to let the back end know that a definition of DECL is
1995 available in this translation unit. */
1997 bool
1999 {
2001 /* This function should only be called at the end of the translation
2002 unit. We cannot be sure of whether or not something will be
2003 COMDAT until that point. */
2006 /* All entities with external linkage that are not COMDAT/EXTERN should be
2007 emitted; they may be referred to from other object files. */
2010 /* Functions marked "dllexport" must be emitted so that they are
2011 visible to other DLLs. */
2016 /* When not optimizing, do not bother to produce definitions for extern
2017 symbols. */
2026 /* If this entity was used, let the back end see it; it will decide
2027 whether or not to emit it into the object file. */
2030 /* Virtual functions might be needed for devirtualization. */
2035 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
2036 reference to DECL might cause it to be emitted later. */
2038 }
2040 /* If necessary, write out the vtables for the dynamic class CTYPE.
2041 Returns true if any vtables were emitted. */
2043 static bool
2045 {
2046 tree vtbl;
2047 tree primary_vtbl;
2051 /* If the vtables for this class have already been emitted there is
2052 nothing more to do. */
2056 /* Ignore dummy vtables made by get_vtable_decl. */
2060 /* On some targets, we cannot determine the key method until the end
2061 of the translation unit -- which is when this function is
2062 called. */
2066 /* See if any of the vtables are needed. */
2068 {
2072 }
2074 {
2075 /* If the references to this class' vtables are optimized away,
2076 still emit the appropriate debugging information. See
2077 dfs_debug_mark. */
2082 }
2084 /* The ABI requires that we emit all of the vtables if we emit any
2085 of them. */
2087 {
2088 /* Mark entities references from the virtual table as used. */
2092 {
2095 LOOKUP_NORMAL);
2097 /* It had better be all done at compile-time. */
2099 }
2101 /* Write it out. */
2105 /* Because we're only doing syntax-checking, we'll never end up
2106 actually marking the variable as written. */
2110 {
2115 }
2116 }
2118 /* Since we're writing out the vtable here, also write the debug
2119 info. */
2123 }
2125 /* A special return value from type_visibility meaning internal
2126 linkage. */
2130 /* walk_tree helper function for type_visibility. */
2132 static tree
2134 {
2137 {
2139 }
2142 {
2145 }
2150 }
2152 /* Returns the visibility of TYPE, which is the minimum visibility of its
2153 component types. */
2155 static int
2157 {
2161 }
2163 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2164 specified (or if VISIBILITY is static). If TMPL is true, this
2165 constraint is for a template argument, and takes precedence
2166 over explicitly-specified visibility on the template. */
2168 static void
2170 {
2172 {
2173 /* extern "C" declarations aren't affected by the anonymous
2174 namespace. */
2176 {
2182 {
2187 }
2191 }
2192 }
2195 {
2197 /* This visibility was not specified. */
2199 }
2200 }
2202 /* Constrain the visibility of DECL based on the visibility of its template
2203 arguments. */
2205 static void
2207 {
2208 /* If this is a template instantiation, check the innermost
2209 template args for visibility constraints. The outer template
2210 args are covered by the class check. */
2214 {
2221 {
2226 {
2229 else
2231 }
2232 }
2235 }
2236 }
2238 /* Like c_determine_visibility, but with additional C++-specific
2239 behavior.
2241 Function-scope entities can rely on the function's visibility because
2242 it is set in start_preparsed_function.
2244 Class-scope entities cannot rely on the class's visibility until the end
2245 of the enclosing class definition.
2247 Note that because namespaces have multiple independent definitions,
2248 namespace visibility is handled elsewhere using the #pragma visibility
2249 machinery rather than by decorating the namespace declaration.
2251 The goal is for constraints from the type to give a diagnostic, and
2252 other constraints to be applied silently. */
2254 void
2256 {
2262 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2264 /* Only relevant for names with external linkage. */
2268 /* Cloned constructors and destructors get the same visibility as
2269 the underlying function. That should be set up in
2270 maybe_clone_body. */
2277 {
2282 else
2284 }
2287 else
2290 /* If DECL is a member of a class, visibility specifiers on the
2291 class can influence the visibility of the DECL. */
2294 else
2295 {
2296 /* Not a class member. */
2298 /* Virtual tables have DECL_CONTEXT set to their associated class,
2299 so they are automatically handled above. */
2304 {
2305 /* Local statics and classes get the visibility of their
2306 containing function by default, except that
2307 -fvisibility-inlines-hidden doesn't affect them. */
2310 {
2314 }
2315 else
2316 {
2320 {
2324 }
2325 else
2326 {
2330 }
2331 }
2333 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2334 but have no TEMPLATE_INFO, so don't try to check it. */
2336 }
2339 {
2340 /* Under -fvisibility-ms-compat, types are visible by default,
2341 even though their contents aren't. */
2348 else
2350 }
2352 {
2353 /* tinfo visibility is based on the type it's for. */
2354 constrain_visibility
2357 /* Give the target a chance to override the visibility associated
2358 with DECL. */
2364 }
2366 /* Template instantiations and specializations get visibility based
2369 {
2372 else
2373 {
2374 /* Set default visibility to whatever the user supplied with
2375 #pragma GCC visibility or a namespace visibility attribute. */
2378 }
2379 }
2380 }
2383 {
2384 /* If the specialization doesn't specify visibility, use the
2385 visibility from the template. */
2395 {
2399 {
2403 else
2404 {
2408 }
2409 }
2412 /* Template argument visibility outweighs #pragma or namespace
2413 visibility, but not an explicit attribute. */
2415 {
2418 {
2419 /* A class template member with explicit visibility
2420 overrides the class visibility, so we need to apply
2421 all the levels of template args directly. */
2424 {
2427 }
2428 }
2430 /* Limit visibility based on its template arguments. */
2432 }
2433 }
2434 }
2440 /* Names in an anonymous namespace get internal linkage.
2441 This might change once we implement export. */
2444 {
2445 /* Propagate anonymity from type to decl. */
2450 }
2452 /* DR 757: A type without linkage shall not be used as the type of a
2453 variable or function with linkage, unless
2454 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2455 o the variable or function is not used (3.2 [basic.def.odr]) or is
2456 defined in the same translation unit.
2458 Since non-extern "C" decls need to be defined in the same
2459 translation unit, we can make the type internal. */
2462 /* If visibility changed and DECL already has DECL_RTL, ensure
2463 symbol flags are updated. */
2470 }
2472 /* By default, static data members and function members receive
2473 the visibility of their containing class. */
2475 static void
2477 {
2483 else
2484 {
2485 /* Default to the class visibility. */
2489 }
2491 /* Give the target a chance to override the visibility associated
2492 with DECL. */
2496 /* Construction virtual tables are not exported because
2497 they cannot be referred to from other object files;
2498 their name is not standardized by the ABI. */
2504 }
2506 /* Returns true iff DECL is an inline that should get hidden visibility
2507 because of -fvisibility-inlines-hidden. */
2509 static bool
2511 {
2513 /* Don't do this for inline templates; specializations might not be
2514 inline, and we don't want them to inherit the hidden
2515 visibility. We'll set it here for all inline instantiations. */
2516 && !processing_template_decl
2521 }
2523 /* Constrain the visibility of a class TYPE based on the visibility of its
2524 field types. Warn if any fields require lesser visibility. */
2526 void
2528 {
2529 tree binfo;
2530 tree t;
2539 /* Don't warn about visibility if the class has explicit visibility. */
2545 {
2550 {
2555 }
2562 }
2566 {
2570 {
2575 }
2581 }
2582 }
2584 /* Functions for adjusting the visibility of a tagged type and its nested
2585 types and declarations when it gets a name for linkage purposes from a
2586 typedef. */
2591 /* First reset the visibility of all the types. */
2593 static void
2595 {
2600 }
2601 static void
2603 {
2605 }
2607 /* Then reset the visibility of any static data members or member
2608 functions that use those types. */
2610 static void
2612 {
2621 }
2622 static void
2624 {
2626 {
2628 {
2633 }
2635 {
2641 }
2649 }
2650 }
2651 static void
2653 {
2655 }
2656 void
2658 {
2661 }
2663 /* Set up our initial idea of what the linkage of DECL should be. */
2665 void
2667 {
2669 /* We've already made a decision as to how this function will
2672 {
2675 {
2679 /* A non-template inline function with external linkage will
2680 always be COMDAT. As we must eventually determine the
2681 linkage of all functions, and as that causes writes to
2682 the data mapped in from the PCH file, it's advantageous
2683 to mark the functions at this point. */
2687 {
2688 /* This function must have external linkage, as
2689 otherwise DECL_INTERFACE_KNOWN would have been
2690 set. */
2694 }
2695 }
2698 }
2699 }
2701 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2702 for DECL has not already been determined, do so now by setting
2703 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2704 function is called entities with vague linkage whose definitions
2705 are available must have TREE_PUBLIC set.
2707 If this function decides to place DECL in COMDAT, it will set
2708 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2709 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2710 callers defer that decision until it is clear that DECL is actually
2711 required. */
2713 void
2715 {
2724 /* We cannot determine what linkage to give to an entity with vague
2725 linkage until the end of the file. For example, a virtual table
2726 for a class will be defined if and only if the key method is
2727 defined in this translation unit. As a further example, consider
2728 that when compiling a translation unit that uses PCH file with
2729 "-frepo" it would be incorrect to make decisions about what
2730 entities to emit when building the PCH; those decisions must be
2731 delayed until the repository information has been processed. */
2733 /* Object file linkage for explicit instantiations is handled in
2734 mark_decl_instantiated. For static variables in functions with
2735 vague linkage, maybe_commonize_var is used.
2737 Therefore, the only declarations that should be provided to this
2738 function are those with external linkage that are:
2740 * implicit instantiations of function templates
2742 * inline function
2744 * implicit instantiations of static data members of class
2745 templates
2747 * virtual tables
2749 * typeinfo objects
2751 Furthermore, all entities that reach this point must have a
2752 definition available in this translation unit.
2754 The following assertions check these conditions. */
2756 /* Any code that creates entities with TREE_PUBLIC cleared should
2757 also set DECL_INTERFACE_KNOWN. */
2763 else
2767 /* Check that a definition of DECL is available in this translation
2768 unit. */
2771 /* Assume that DECL will not have COMDAT linkage. */
2773 /* Assume that DECL will not be imported into this translation
2774 unit. */
2777 /* See if the repository tells us whether or not to emit DECL in
2778 this translation unit. */
2783 {
2784 /* The repository indicates that this entity should be defined
2785 here. Make sure the back end honors that request. */
2787 /* Output the definition as an ordinary strong definition. */
2791 }
2794 /* We have already decided what to do with this DECL; there is no
2795 need to check anything further. */
2796 ;
2798 {
2810 /* The ABI requires that all virtual tables be emitted with
2811 COMDAT linkage. However, on systems where COMDAT symbols
2812 don't show up in the table of contents for a static
2813 archive, or on systems without weak symbols (where we
2814 approximate COMDAT linkage by using internal linkage), the
2815 linker will report errors about undefined symbols because
2816 it will not see the virtual table definition. Therefore,
2817 in the case that we know that the virtual table will be
2818 emitted in only one translation unit, we make the virtual
2819 table an ordinary definition with external linkage. */
2822 {
2823 /* CLASS_TYPE is being exported from this translation unit,
2824 so DECL should be defined here. */
2826 /* If a class is declared in a header with the "extern
2827 template" extension, then it will not be instantiated,
2828 even in translation units that would normally require
2829 it. Often such classes are explicitly instantiated in
2830 one translation unit. Therefore, the explicit
2831 instantiation must be made visible to other translation
2832 units. */
2834 else
2835 {
2836 /* The generic C++ ABI says that class data is always
2837 COMDAT, even if there is a key function. Some
2838 variants (e.g., the ARM EABI) says that class data
2839 only has COMDAT linkage if the class data might be
2840 emitted in more than one translation unit. When the
2841 key method can be inline and is inline, we still have
2842 to arrange for comdat even though
2843 class_data_always_comdat is false. */
2847 {
2848 /* The ABI requires COMDAT linkage. Normally, we
2849 only emit COMDAT things when they are needed;
2850 make sure that we realize that this entity is
2851 indeed needed. */
2854 }
2855 }
2856 }
2860 else
2862 }
2864 {
2867 {
2873 /* If -fno-rtti was specified, then we cannot be sure
2874 that RTTI information will be emitted with the
2875 virtual table of the class, so we must emit it
2876 wherever it is used. */
2879 else
2880 {
2883 {
2889 {
2892 }
2893 }
2894 else
2896 }
2897 }
2898 else
2900 }
2902 {
2903 /* DECL is an implicit instantiation of a function or static
2904 data member. */
2907 || (flag_implicit_inline_templates
2911 else
2912 /* If we are not implicitly generating templates, then mark
2913 this entity as undefined in this translation unit. */
2915 }
2917 {
2919 {
2923 {
2927 && ! flag_implement_inlines
2933 /* Always make artificials weak. */
2936 else
2938 }
2939 }
2940 else
2942 }
2943 else
2947 {
2948 /* If we are importing DECL into this translation unit, mark is
2949 an undefined here. */
2952 }
2954 {
2955 /* If we decided to put DECL in COMDAT, mark it accordingly at
2956 this point. */
2958 }
2961 }
2963 /* Return an expression that performs the destruction of DECL, which
2964 must be a VAR_DECL whose type has a non-trivial destructor, or is
2965 an array whose (innermost) elements have a non-trivial destructor. */
2967 tree
2969 {
2973 }
2975 /* Returns the initialization guard variable for the variable DECL,
2976 which has static storage duration. */
2978 tree
2980 {
2981 tree sname;
2982 tree guard;
2987 {
2988 tree guard_type;
2990 /* We use a type that is big enough to contain a mutex as well
2991 as an integer counter. */
2996 /* The guard should have the same linkage as what it guards. */
3013 }
3015 }
3017 /* Return those bits of the GUARD variable that should be set when the
3018 guarded entity is actually initialized. */
3020 static tree
3022 {
3024 {
3025 /* We only set the first byte of the guard, in order to leave room
3026 for a mutex in the high-order bits. */
3029 guard);
3032 guard);
3034 }
3037 }
3039 /* Return an expression which determines whether or not the GUARD
3040 variable has already been initialized. */
3042 tree
3044 {
3045 tree guard_value;
3047 /* Check to see if the GUARD is zero. */
3050 /* Mask off all but the low bit. */
3052 {
3058 tf_warning_or_error);
3059 }
3066 tf_warning_or_error);
3067 }
3069 /* Return an expression which sets the GUARD variable, indicating that
3070 the variable being guarded has been initialized. */
3072 tree
3074 {
3075 tree guard_init;
3077 /* Set the GUARD to one. */
3083 tf_warning_or_error);
3084 }
3086 /* Returns true iff we can tell that VAR does not have a dynamic
3087 initializer. */
3089 static bool
3091 {
3092 /* If it's defined in another TU, we can't tell. */
3095 /* If it has a non-trivial destructor, registering the destructor
3096 counts as dynamic initialization. */
3099 /* If it's in this TU, its initializer has been processed. */
3101 /* If it has no initializer or a constant one, it's not dynamic. */
3104 }
3106 /* Returns true iff VAR is a variable that needs uses to be
3107 wrapped for possible dynamic initialization. */
3109 static bool
3111 {
3117 }
3119 /* Get the FUNCTION_DECL for the shared TLS init function for this
3120 translation unit. */
3122 static tree
3124 {
3128 {
3131 void_list_node));
3137 }
3139 }
3141 /* Get a FUNCTION_DECL for the init function for the thread_local
3142 variable VAR. The init function will be an alias to the function
3143 that initializes all the non-local TLS variables in the translation
3144 unit. The init function is only used by the wrapper function. */
3146 static tree
3148 {
3149 /* Only C++11 TLS vars need this init fn. */
3153 /* If -fno-extern-tls-init, assume that we don't need to call
3154 a tls init function for a variable defined in another TU. */
3158 #ifdef ASM_OUTPUT_DEF
3159 /* If the variable is internal, or if we can't generate aliases,
3160 call the local init function directly. */
3162 #endif
3168 {
3171 void_list_node));
3180 {
3182 /* If the variable is defined somewhere else and might have static
3183 initialization, make the init function a weak reference. */
3189 else
3191 }
3201 }
3203 }
3205 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3206 variable VAR. The wrapper function calls the init function (if any) for
3207 VAR and then returns a reference to VAR. The wrapper function is used
3208 in place of VAR everywhere VAR is mentioned. */
3210 tree
3212 {
3213 /* Only C++11 TLS vars need this wrapper fn. */
3220 {
3221 /* A named rvalue reference is an lvalue, so the wrapper should
3222 always return an lvalue reference. */
3231 /* The wrapper is inline and emitted everywhere var is used. */
3234 {
3236 #ifdef HAVE_GAS_HIDDEN
3237 /* Make the wrapper bind locally; there's no reason to share
3238 the wrapper between multiple shared objects. */
3241 #endif
3242 }
3248 #if 0
3249 /* We want CSE to commonize calls to the wrapper, but marking it as
3250 pure is unsafe since it has side-effects. I guess we need a new
3251 ECF flag even weaker than ECF_PURE. FIXME! */
3253 #endif
3258 }
3260 }
3262 /* At EOF, generate the definition for the TLS wrapper function FN:
3264 T& var_wrapper() {
3265 if (init_fn) init_fn();
3266 return var;
3267 } */
3269 static void
3271 {
3276 /* Only call the init fn if there might be one. */
3278 {
3280 /* If init_fn is a weakref, make sure it exists before calling. */
3282 {
3287 tf_warning_or_error);
3289 }
3293 {
3296 }
3297 }
3298 else
3299 /* If there's no initialization, the wrapper is a constant function. */
3304 }
3306 /* Start the process of running a particular set of global constructors
3307 or destructors. Subroutine of do_[cd]tors. Also called from
3308 vtv_start_verification_constructor_init_function. */
3310 static tree
3312 {
3313 tree body;
3314 tree fndecl;
3317 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3320 {
3323 #ifdef JOINER
3325 #else
3327 #endif
3330 }
3331 else
3337 NULL_TREE));
3342 /* Mark as artificial because it's not explicitly in the user's
3343 source code. */
3346 /* Mark this declaration as used to avoid spurious warnings. */
3349 /* Mark this function as a global constructor or destructor. */
3352 else
3358 }
3360 /* Finish the process of running a particular set of global constructors
3361 or destructors. Subroutine of do_[cd]tors. */
3363 static void
3365 {
3366 tree fn;
3368 /* Finish up. */
3373 {
3376 }
3377 else
3378 {
3381 }
3384 }
3386 /* The names of the parameters to the function created to handle
3387 initializations and destructions for objects with static storage
3388 duration. */
3392 /* The name of the function we create to handle initializations and
3393 destructions for objects with static storage duration. */
3396 /* The declaration for the __INITIALIZE_P argument. */
3399 /* The declaration for the __PRIORITY argument. */
3402 /* The declaration for the static storage duration function. */
3405 /* All the static storage duration functions created in this
3406 translation unit. */
3409 /* A map from priority levels to information about that priority
3410 level. There may be many such levels, so efficient lookup is
3411 important. */
3414 /* Begins the generation of the function that will handle all
3415 initialization and destruction of objects with static storage
3416 duration. The function generated takes two parameters of type
3417 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3418 nonzero, it performs initializations. Otherwise, it performs
3419 destructions. It only performs those initializations or
3420 destructions with the indicated __PRIORITY. The generated function
3421 returns no value.
3423 It is assumed that this function will only be called once per
3424 translation unit. */
3426 static tree
3428 {
3429 tree type;
3430 tree body;
3433 /* Create the identifier for this function. It will be of the form
3434 SSDF_IDENTIFIER_<number>. */
3439 NULL_TREE);
3441 /* Create the FUNCTION_DECL itself. */
3444 type);
3448 /* Put this function in the list of functions to be called from the
3449 static constructors and destructors. */
3451 {
3454 /* Take this opportunity to initialize the map from priority
3455 numbers to information about that priority level. */
3458 /*delete_value_fn=*/
3461 /* We always need to generate functions for the
3462 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3463 priorities later, we'll be sure to find the
3464 DEFAULT_INIT_PRIORITY. */
3466 }
3470 /* Create the argument list. */
3471 initialize_p_decl = cp_build_parm_decl
3475 priority_decl = cp_build_parm_decl
3483 /* Put the function in the global scope. */
3486 /* Start the function itself. This is equivalent to declaring the
3487 function as:
3489 static void __ssdf (int __initialize_p, init __priority_p);
3491 It is static because we only need to call this function from the
3492 various constructor and destructor functions for this module. */
3495 SF_PRE_PARSED);
3497 /* Set up the scope of the outermost block in the function. */
3501 }
3503 /* Finish the generation of the function which performs initialization
3504 and destruction of objects with static storage duration. After
3505 this point, no more such objects can be created. */
3507 static void
3509 {
3510 /* Close out the function. */
3513 }
3515 /* Return the information about the indicated PRIORITY level. If no
3516 code to handle this level has yet been generated, generate the
3517 appropriate prologue. */
3519 static priority_info
3521 {
3522 priority_info pi;
3523 splay_tree_node n;
3528 {
3529 /* Create a new priority information structure, and insert it
3530 into the map. */
3537 }
3538 else
3542 }
3544 /* The effective initialization priority of a DECL. */
3546 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3547 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3548 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3550 /* Whether a DECL needs a guard to protect it against multiple
3551 initialization. */
3553 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3554 || DECL_ONE_ONLY (decl) \
3555 || DECL_WEAK (decl)))
3557 /* Called from one_static_initialization_or_destruction(),
3558 via walk_tree.
3559 Walks the initializer list of a global variable and looks for
3560 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3561 and that have their DECL_CONTEXT() == NULL.
3562 For each such temporary variable, set their DECL_CONTEXT() to
3563 the current function. This is necessary because otherwise
3564 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3565 when trying to refer to a temporary variable that does not have
3566 it's DECL_CONTECT() properly set. */
3567 static tree
3571 {
3575 {
3576 tree var;
3584 }
3587 }
3589 /* Set up to handle the initialization or destruction of DECL. If
3590 INITP is nonzero, we are initializing the variable. Otherwise, we
3591 are destroying it. */
3593 static void
3595 {
3597 tree guard;
3599 /* If we are supposed to destruct and there's a trivial destructor,
3600 nothing has to be done. */
3605 /* Trick the compiler into thinking we are at the file and line
3606 where DECL was declared so that error-messages make sense, and so
3607 that the debugger will show somewhat sensible file and line
3608 information. */
3611 /* Make sure temporary variables in the initialiser all have
3612 their DECL_CONTEXT() set to a value different from NULL_TREE.
3613 This can happen when global variables initialisers are built.
3614 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3615 the temporary variables that might have been generated in the
3616 accompagning initialisers is NULL_TREE, meaning the variables have been
3617 declared in the global namespace.
3618 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3619 of the temporaries are set to the current function decl. */
3621 fix_temporary_vars_context_r,
3622 NULL);
3624 /* Because of:
3626 [class.access.spec]
3628 Access control for implicit calls to the constructors,
3629 the conversion functions, or the destructor called to
3630 create and destroy a static data member is performed as
3631 if these calls appeared in the scope of the member's
3632 class.
3634 we pretend we are in a static member function of the class of
3635 which the DECL is a member. */
3637 {
3640 }
3642 /* Assume we don't need a guard. */
3644 /* We need a guard if this is an object with external linkage that
3645 might be initialized in more than one place. (For example, a
3646 static data member of a template, when the data member requires
3647 construction.) */
3649 {
3650 tree guard_cond;
3654 /* When using __cxa_atexit, we just check the GUARD as we would
3655 for a local static. */
3657 {
3658 /* When using __cxa_atexit, we never try to destroy
3659 anything from a static destructor. */
3662 }
3663 /* If we don't have __cxa_atexit, then we will be running
3664 destructors from .fini sections, or their equivalents. So,
3665 we need to know how many times we've tried to initialize this
3666 object. We do initializations only if the GUARD is zero,
3667 i.e., if we are the first to initialize the variable. We do
3668 destructions only if the GUARD is one, i.e., if we are the
3669 last to destroy the variable. */
3671 guard_cond
3673 EQ_EXPR,
3675 guard,
3677 tf_warning_or_error),
3678 integer_one_node,
3679 tf_warning_or_error);
3680 else
3681 guard_cond
3683 EQ_EXPR,
3685 guard,
3687 tf_warning_or_error),
3688 integer_zero_node,
3689 tf_warning_or_error);
3693 }
3696 /* If we're using __cxa_atexit, we have not already set the GUARD,
3697 so we must do so now. */
3701 /* Perform the initialization or destruction. */
3703 {
3705 {
3708 {
3712 }
3713 }
3715 /* If we're using __cxa_atexit, register a function that calls the
3716 destructor for the object. */
3719 }
3720 else
3723 /* Finish the guard if-stmt, if necessary. */
3725 {
3728 }
3730 /* Now that we're done with DECL we don't need to pretend to be a
3731 member of its class any longer. */
3734 }
3736 /* Generate code to do the initialization or destruction of the decls in VARS,
3737 a TREE_LIST of VAR_DECL with static storage duration.
3738 Whether initialization or destruction is performed is specified by INITP. */
3740 static void
3742 {
3745 /* Build the outer if-stmt to check for initialization or destruction. */
3749 EQ_EXPR,
3750 initialize_p_decl,
3751 cond,
3752 tf_warning_or_error);
3755 /* To make sure dynamic construction doesn't access globals from other
3756 compilation units where they might not be yet constructed, for
3757 -fsanitize=address insert __asan_before_dynamic_init call that
3758 prevents access to either all global variables that need construction
3759 in other compilation units, or at least those that haven't been
3760 initialized yet. Variables that need dynamic construction in
3761 the current compilation unit are kept accessible. */
3768 tree priority_if_stmt;
3770 priority_info pi;
3772 /* If we don't need a destructor, there's nothing to do. Avoid
3773 creating a possibly empty if-stmt. */
3775 {
3778 }
3780 /* Remember that we had an initialization or finalization at this
3781 priority. */
3786 else
3789 /* Conditionalize this initialization on being in the right priority
3790 and being initializing/finalizing appropriately. */
3793 EQ_EXPR,
3794 priority_decl,
3796 tf_warning_or_error);
3799 /* Process initializers with same priority. */
3803 /* Do one initialization or destruction. */
3807 /* Finish up the priority if-stmt body. */
3813 /* Revert what __asan_before_dynamic_init did by calling
3814 __asan_after_dynamic_init. */
3818 /* Finish up the init/destruct if-stmt body. */
3821 }
3823 /* VARS is a list of variables with static storage duration which may
3824 need initialization and/or finalization. Remove those variables
3825 that don't really need to be initialized or finalized, and return
3826 the resulting list. The order in which the variables appear in
3827 VARS is in reverse order of the order in which they should actually
3828 be initialized. The list we return is in the unreversed order;
3829 i.e., the first variable should be initialized first. */
3831 static tree
3833 {
3838 {
3843 /* Deal gracefully with error. */
3845 {
3848 }
3850 /* The only things that can be initialized are variables. */
3853 /* If this object is not defined, we don't need to do anything
3854 here. */
3856 {
3859 }
3861 /* Also, if the initializer already contains errors, we can bail
3862 out now. */
3865 {
3868 }
3870 /* This variable is going to need initialization and/or
3871 finalization, so we add it to the list. */
3875 }
3878 }
3880 /* Make sure we have told the back end about all the variables in
3881 VARS. */
3883 static void
3885 {
3886 tree v;
3889 {
3892 {
3895 }
3896 }
3897 }
3899 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
3900 (otherwise) that will initialize all global objects with static
3901 storage duration having the indicated PRIORITY. */
3903 static void
3906 {
3908 tree fndecl;
3909 tree body;
3913 /* ??? */
3914 /* Was: locus->line++; */
3916 /* We use `I' to indicate initialization and `D' to indicate
3917 destruction. */
3920 /* We emit the function lazily, to avoid generating empty
3921 global constructors and destructors. */
3924 /* For Objective-C++, we may need to initialize metadata found in this module.
3925 This must be done _before_ any other static initializations. */
3928 {
3931 }
3933 /* Call the static storage duration function with appropriate
3934 arguments. */
3936 {
3937 /* Calls to pure or const functions will expand to nothing. */
3939 {
3940 tree call;
3947 constructor_p),
3949 priority),
3950 NULL_TREE);
3952 }
3953 }
3955 /* Close out the function. */
3958 }
3960 /* Generate constructor and destructor functions for the priority
3961 indicated by N. */
3963 static int
3965 {
3970 /* Generate the functions themselves, but only if they are really
3971 needed. */
3977 /* Keep iterating. */
3979 }
3981 /* Java requires that we be able to reference a local address for a
3982 method, and not be confused by PLT entries. If hidden aliases are
3983 supported, collect and return all the functions for which we should
3984 emit a hidden alias. */
3988 {
3992 #ifndef HAVE_GAS_HIDDEN
3994 #endif
3997 {
4003 {
4007 }
4008 }
4011 }
4014 /* Java requires that we be able to reference a local address for a
4015 method, and not be confused by PLT entries. If hidden aliases are
4016 supported, emit one for each java function that we've emitted.
4017 CANDIDATES is the set of FUNCTION_DECLs that were gathered
4018 by collect_candidates_for_java_method_aliases. */
4020 static void
4022 {
4025 #ifndef HAVE_GAS_HIDDEN
4027 #endif
4030 {
4035 {
4036 /* Mangle the name in a predictable way; we need to reference
4037 this from a java compiled object file. */
4053 }
4054 }
4055 }
4057 /* Return C++ property of T, based on given operation OP. */
4059 static int
4061 {
4063 {
4078 }
4079 }
4081 /* Collect source file references recursively, starting from NAMESPC. */
4083 static void
4085 {
4086 tree t;
4091 /* Iterate over names in this name space. */
4096 /* Dump siblings, if any */
4099 /* Dump children, if any */
4101 }
4103 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4104 starting from NAMESPC. */
4106 static void
4108 {
4112 /* Collect decls from this namespace */
4115 /* Collect siblings, if any */
4118 /* Collect children, if any */
4120 }
4122 /* Returns true iff there is a definition available for variable or
4123 function DECL. */
4125 static bool
4127 {
4130 else
4131 {
4134 }
4135 }
4137 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4139 [expr.const]
4141 An integral constant-expression can only involve ... const
4142 variables of integral or enumeration types initialized with
4143 constant expressions ...
4145 C++0x also allows constexpr variables and temporaries initialized
4146 with constant expressions. We handle the former here, but the latter
4147 are just folded away in cxx_eval_constant_expression.
4149 The standard does not require that the expression be non-volatile.
4150 G++ implements the proposed correction in DR 457. */
4152 bool
4154 {
4158 /* We don't know if a template static data member is initialized with
4159 a constant expression until we instantiate its initializer. Even
4160 in the case of a constexpr variable, we can't treat it as a
4161 constant until its initializer is complete in case it's used in
4162 its own initializer. */
4165 }
4167 /* Returns true if DECL could be a symbolic constant variable, depending on
4168 its initializer. */
4170 bool
4172 {
4180 }
4182 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4183 called from grokfndecl and grokvardecl; in all modes it is called from
4184 cp_write_global_declarations. */
4186 void
4188 {
4190 /* In C++11 it's ok if the decl is defined. */
4194 /* The type that got us on no_linkage_decls must have gotten a name for
4197 /* The type might end up having a typedef name for linkage purposes. */
4200 {
4208 /* DRs 132, 319 and 389 seem to indicate types with
4209 no linkage can only be used to declare extern "C"
4210 entities. Since it's not always an error in the
4211 ISO C++ 90 Standard, we only issue a warning. */
4213 "with no linkage used to declare variable %q#D with "
4215 else
4218 decl);
4223 }
4230 else
4233 }
4235 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4237 static void
4239 {
4241 }
4243 /* Clear DECL_EXTERNAL for NODE. */
4245 static bool
4247 {
4250 }
4252 /* Build up the function to run dynamic initializers for thread_local
4253 variables in this translation unit and alias the init functions for the
4254 individual variables to it. */
4256 static void
4258 {
4268 boolean_type_node);
4282 tf_warning_or_error);
4285 tf_warning_or_error));
4287 {
4292 #ifdef ASM_OUTPUT_DEF
4293 /* Output init aliases even with -fno-extern-tls-init. */
4295 {
4299 cgraph_node *alias
4303 }
4304 #endif
4305 }
4311 }
4313 /* The entire file is now complete. If requested, dump everything
4314 to a file. */
4316 static void
4318 {
4323 {
4326 }
4327 }
4329 /* Check the deallocation functions for CODE to see if we want to warn that
4330 only one was defined. */
4332 static void
4334 {
4340 {
4342 /* We're only interested in usual deallocation functions. */
4347 else
4349 }
4356 }
4358 /* Check the global deallocation functions to see if we want to warn about
4359 defining unsized without sized (or vice versa). */
4361 static void
4363 {
4368 }
4370 /* This routine is called at the end of compilation.
4371 Its job is to create all the code needed to initialize and
4372 destroy the global aggregates. We do the destruction
4373 first, since that way we only need to reverse the decls once. */
4375 void
4377 {
4378 tree vars;
4381 location_t locus;
4384 tree decl;
4390 /* Bad parse errors. Just forget about it. */
4395 /* This is the point to write out a PCH if we're doing that.
4396 In that case we do not want to do anything else. */
4398 {
4402 }
4406 /* Handle -fdump-ada-spec[-slim] */
4408 {
4411 else
4415 }
4417 /* FIXME - huh? was input_line -= 1;*/
4421 /* We now have to write out all the stuff we put off writing out.
4422 These include:
4424 o Template specializations that we have not yet instantiated,
4425 but which are needed.
4426 o Initialization and destruction for non-local objects with
4427 static storage duration. (Local objects with static storage
4428 duration are initialized when their scope is first entered,
4429 and are cleaned up via atexit.)
4430 o Virtual function tables.
4432 All of these may cause others to be needed. For example,
4433 instantiating one function may cause another to be needed, and
4434 generating the initializer for an object may cause templates to be
4435 instantiated, etc., etc. */
4439 do
4440 {
4441 tree t;
4442 tree decl;
4446 /* If there are templates that we've put off instantiating, do
4447 them now. */
4451 /* Write out virtual tables as required. Note that writing out
4452 the virtual table for a template class may cause the
4453 instantiation of members of that class. If we write out
4454 vtables then we remove the class from our list so we don't
4455 have to look at it again. */
4459 {
4462 }
4466 {
4470 {
4472 {
4475 }
4476 else
4480 }
4481 }
4483 /* Write out needed type info variables. We have to be careful
4484 looping through unemitted decls, because emit_tinfo_decl may
4485 cause other variables to be needed. New elements will be
4486 appended, and we remove from the vector those that actually
4487 get emitted. */
4491 {
4494 }
4496 /* The list of objects with static storage duration is built up
4497 in reverse order. We clear STATIC_AGGREGATES so that any new
4498 aggregates added during the initialization of these will be
4499 initialized in the correct order when we next come around the
4500 loop. */
4504 {
4505 /* We need to start a new initialization function each time
4506 through the loop. That's because we need to know which
4507 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4508 isn't computed until a function is finished, and written
4509 out. That's a deficiency in the back end. When this is
4510 fixed, these initialization functions could all become
4511 inline, with resulting performance improvements. */
4512 tree ssdf_body;
4514 /* Set the line and file, so that it is obviously not from
4515 the source file. */
4519 /* Make sure the back end knows about all the variables. */
4522 /* First generate code to do all the initializations. */
4526 /* Then, generate code to do all the destructions. Do these
4527 in reverse order so that the most recently constructed
4528 variable is the first destroyed. If we're using
4529 __cxa_atexit, then we don't need to do this; functions
4530 were registered at initialization time to destroy the
4531 local statics. */
4533 {
4536 }
4537 else
4540 /* Finish up the static storage duration function for this
4541 round. */
4545 /* All those initializations and finalizations might cause
4546 us to need more inline functions, more template
4547 instantiations, etc. */
4549 ssdf_count++;
4550 /* ??? was: locus.line++; */
4551 }
4553 /* Now do the same for thread_local variables. */
4556 /* Go through the set of inline functions whose bodies have not
4557 been emitted yet. If out-of-line copies of these functions
4558 are required, emit them. */
4560 {
4561 /* Does it need synthesizing? */
4564 {
4565 /* Even though we're already at the top-level, we push
4566 there again. That way, when we pop back a few lines
4567 hence, all of our state is restored. Otherwise,
4568 finish_function doesn't clean things up, and we end
4569 up with CURRENT_FUNCTION_DECL set. */
4571 /* The decl's location will mark where it was first
4572 needed. Save that so synthesize method can indicate
4573 where it was needed from, in case of error */
4578 }
4586 /* We lie to the back end, pretending that some functions
4587 are not defined when they really are. This keeps these
4588 functions from being put out unnecessarily. But, we must
4589 stop lying when the functions are referenced, or if they
4590 are not comdat since they need to be put out now. If
4591 DECL_INTERFACE_KNOWN, then we have already set
4592 DECL_EXTERNAL appropriately, so there's no need to check
4593 again, and we do not want to clear DECL_EXTERNAL if a
4594 previous call to import_export_decl set it.
4596 This is done in a separate for cycle, because if some
4597 deferred function is contained in another deferred
4598 function later in deferred_fns varray,
4599 rest_of_compilation would skip this function and we
4600 really cannot expand the same function twice. */
4605 {
4614 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4615 group, we need to mark all symbols in the same comdat group
4616 that way. */
4623 }
4625 /* If we're going to need to write this function out, and
4626 there's already a body for it, create RTL for it now.
4627 (There might be no body if this is a method we haven't
4628 gotten around to synthesizing yet.) */
4633 {
4634 /* We will output the function; no longer consider it in this
4635 loop. */
4637 /* Generate RTL for this function now that we know we
4638 need it. */
4640 /* If we're compiling -fsyntax-only pretend that this
4641 function has been written out so that we don't try to
4642 expand it again. */
4646 }
4647 }
4652 /* Static data members are just like namespace-scope globals. */
4654 {
4656 /* Don't write it out if we haven't seen a definition. */
4660 /* If this static data member is needed, provide it to the
4661 back end. */
4664 }
4670 retries++;
4671 }
4674 /* All used inline functions must have a definition at this point. */
4676 {
4679 /* If the definition actually was available here, then the
4680 fact that the function was not defined merely represents
4681 that for some reason (use of a template repository,
4682 #pragma interface, etc.) we decided not to emit the
4683 definition here. */
4685 /* Don't complain if the template was defined. */
4689 {
4691 /* Avoid a duplicate warning from check_global_declaration_1. */
4693 }
4694 }
4696 /* So must decls that use a type with no linkage. */
4702 /* Then, do the Objective-C stuff. This is where all the
4703 Objective-C module stuff gets generated (symtab,
4704 class/protocol/selector lists etc). This must be done after C++
4705 templates, destructors etc. so that selectors used in C++
4706 templates are properly allocated. */
4710 /* We give C linkage to static constructors and destructors. */
4713 /* Generate initialization and destruction functions for all
4714 priorities for which they are required. */
4717 generate_ctor_and_dtor_functions_for_priority,
4720 /* If this is obj-c++ and we need a static init, call
4721 generate_ctor_or_dtor_function. */
4725 /* We're done with the splay-tree now. */
4729 /* Generate any missing aliases. */
4732 /* We're done with static constructors, so we can go back to "C++"
4733 linkage now. */
4736 /* Collect candidates for Java hidden aliases. */
4743 {
4747 }
4752 {
4753 /* Generate the special constructor initialization function that
4754 calls __VLTRegisterPairs, and give it a very high
4755 initialization priority. This must be done after
4756 finalize_compilation_unit so that we have accurate
4757 information about which vtable will actually be emitted. */
4759 }
4764 /* Now, issue warnings about static, but not defined, functions,
4765 etc., and emit debugging information. */
4768 {
4773 }
4777 /* Generate hidden aliases for Java. */
4779 {
4782 }
4786 /* The entire file is now complete. If requested, dump everything
4787 to a file. */
4791 {
4794 }
4797 #ifdef ENABLE_CHECKING
4802 }
4804 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
4805 function to call in parse-tree form; it has not yet been
4806 semantically analyzed. ARGS are the arguments to the function.
4807 They have already been semantically analyzed. This may change
4808 ARGS. */
4810 tree
4812 tsubst_flags_t complain)
4813 {
4814 tree orig_fn;
4816 tree expr;
4817 tree object;
4823 {
4832 /* Transform the arguments and add the implicit "this"
4833 parameter. That must be done before the FN is transformed
4834 because we depend on the form of FN. */
4838 {
4842 }
4843 /* Now that the arguments are done, transform FN. */
4845 }
4847 /* A qualified name corresponding to a bound pointer-to-member is
4848 represented as an OFFSET_REF:
4850 struct B { void g(); };
4851 void (B::*p)();
4852 void B::g() { (this->*p)(); } */
4854 {
4858 complain);
4860 }
4864 else
4873 }
4876 void
4878 {
4883 {
4887 {
4890 }
4891 }
4892 }
4894 /* Return true if function DECL can be inlined. This is used to force
4895 instantiation of methods that might be interesting for inlining. */
4896 bool
4898 {
4904 /* When optimizing, we might inline everything when flatten
4905 attribute or heuristics inlining for size or autoinlining
4906 is used. */
4908 }
4910 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
4911 If DECL is a specialization or implicitly declared class member,
4912 generate the actual definition. Return false if something goes
4913 wrong, true otherwise. */
4915 bool
4917 {
4918 /* If DECL is a BASELINK for a single function, then treat it just
4919 like the DECL for the function. Otherwise, if the BASELINK is
4920 for an overloaded function, we don't know which function was
4921 actually used until after overload resolution. */
4923 {
4928 }
4930 /* Set TREE_USED for the benefit of -Wunused. */
4935 /* Mark enumeration types as used. */
4944 {
4946 {
4949 {
4950 /* We mark a lambda conversion op as deleted if we can't
4951 generate it properly; see maybe_add_lambda_conv_op. */
4955 }
4956 }
4958 {
4962 }
4964 }
4970 /* We can only check DECL_ODR_USED on variables or functions with
4971 DECL_LANG_SPECIFIC set, and these are also the only decls that we
4972 might need special handling for. */
4976 {
4978 {
4982 }
4984 }
4986 /* We only want to do this processing once. We don't need to keep trying
4987 to instantiate inline templates, because unit-at-a-time will make sure
4988 we get them compiled before functions that want to inline them. */
4992 /* If within finish_function, defer the rest until that function
4993 finishes, otherwise it might recurse. */
4995 {
4998 }
5000 /* Normally, we can wait until instantiation-time to synthesize DECL.
5001 However, if DECL is a static data member initialized with a constant
5002 or a constexpr function, we need it right now because a reference to
5003 such a data member or a call to such function is not value-dependent.
5004 For a function that uses auto in the return type, we need to instantiate
5005 it to find out its type. For OpenMP user defined reductions, we need
5006 them instantiated for reduction clauses which inline them by hand
5007 directly. */
5016 {
5017 /* Instantiating a function will result in garbage collection. We
5018 must treat this situation as if we were within the body of a
5019 function so as to avoid collecting live data only referenced from
5020 the stack (such as overload resolution candidates). */
5025 }
5030 /* Check this too in case we're within instantiate_non_dependent_expr. */
5037 /* If we don't need a value, then we don't need to synthesize DECL. */
5045 /* DR 757: A type without linkage shall not be used as the type of a
5046 variable or function with linkage, unless
5047 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5048 o the variable or function is not used (3.2 [basic.def.odr]) or is
5049 defined in the same translation unit. */
5056 {
5058 /* There's no way to define a local extern, and adding it to
5059 the vector interferes with GC, so give an error now. */
5061 else
5063 }
5067 /* Remember it, so we can check it was defined. */
5070 /* Is it a synthesized method that needs to be synthesized? */
5074 /* A function defaulted outside the class is synthesized either by
5075 cp_finish_decl or instantiate_decl. */
5078 {
5079 /* Defer virtual destructors so that thunks get the right
5080 linkage. */
5082 {
5085 }
5087 /* Remember the current location for a function we will end up
5088 synthesizing. Then we can inform the user where it was
5089 required in the case of error. */
5092 /* Synthesizing an implicitly defined member function will result in
5093 garbage collection. We must treat this situation as if we were
5094 within the body of a function so as to avoid collecting live data
5095 on the stack (such as overload resolution candidates).
5097 We could just let cp_write_global_declarations handle synthesizing
5098 this function by adding it to deferred_fns, but doing
5099 it at the use site produces better error messages. */
5103 /* If this is a synthesized method we don't need to
5104 do the instantiation test below. */
5105 }
5110 /* If this is a function or variable that is an instance of some
5111 template, we now know that we will need to actually do the
5112 instantiation. We check that DECL is not an explicit
5113 instantiation because that is not checked in instantiate_decl.
5115 We put off instantiating functions in order to improve compile
5116 times. Maintaining a stack of active functions is expensive,
5117 and the inliner knows to instantiate any functions it might
5118 need. Therefore, we always try to defer instantiation. */
5119 {
5124 }
5127 }
5129 bool
5131 {
5133 }
5135 tree
5137 {
5139 }
5141 tree
5143 {
5144 tree fn;
5152 }