| blob | 07bdd92de93236ccbdea3fe862b20cab3b2ab3b0 |
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 {
1475 attributes
1479 }
1480 else
1486 /* Propagate deprecation out to the template. */
1489 {
1495 }
1496 }
1497 \f
1498 /* Walks through the namespace- or function-scope anonymous union
1499 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1500 Returns one of the fields for use in the mangled name. */
1502 static tree
1504 {
1506 tree field;
1508 /* Rather than write the code to handle the non-union case,
1509 just give an error. */
1511 {
1514 }
1519 {
1520 tree decl;
1521 tree ref;
1526 {
1530 }
1540 else
1545 {
1546 tree base;
1562 }
1565 else
1570 }
1573 }
1575 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1576 anonymous union, then all members must be laid out together. PUBLIC_P
1577 is nonzero if this union is not declared static. */
1579 void
1581 {
1582 tree type;
1583 tree main_decl;
1592 /* The VAR_DECL's context is the same as the TYPE's context. */
1599 {
1602 }
1608 {
1611 }
1614 {
1615 /* Use main_decl to set the mangled name. */
1621 }
1625 }
1626 \f
1627 /* Auxiliary functions to make type signatures for
1628 `operator new' and `operator delete' correspond to
1629 what compiler will be expecting. */
1631 tree
1633 {
1640 {
1643 }
1646 {
1648 {
1649 /* [basic.stc.dynamic.allocation]
1651 The first parameter shall not have an associated default
1652 argument. */
1655 /* Throw away the default argument. */
1657 }
1660 {
1663 }
1664 }
1665 else
1673 {
1676 /* Fall through. */
1678 type = build_exception_variant
1681 /* Fall through. */
1683 }
1685 }
1687 tree
1689 {
1696 {
1699 }
1703 {
1708 ptr_type_node);
1709 }
1711 {
1714 /* Fall through. */
1716 type = build_exception_variant
1719 /* Fall through. */
1721 }
1724 }
1725 \f
1726 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1727 and mark them as needed. */
1729 static void
1731 {
1732 tree fnaddr;
1737 {
1738 tree fn;
1744 /* This entry is an offset: a virtual base class offset, a
1745 virtual call offset, an RTTI offset, etc. */
1750 /* When we don't have vcall offsets, we output thunks whenever
1751 we output the vtables that contain them. With vcall offsets,
1752 we know all the thunks we'll need when we emit a virtual
1753 function, so we emit the thunks there instead. */
1757 }
1758 }
1760 /* Set DECL up to have the closest approximation of "initialized common"
1761 linkage available. */
1763 void
1765 {
1770 /* We can just emit function and compiler-generated variables
1771 statically; having multiple copies is (for the most part) only
1772 a waste of space.
1774 There are two correctness issues, however: the address of a
1775 template instantiation with external linkage should be the
1776 same, independent of what translation unit asks for the
1777 address, and this will not hold when we emit multiple copies of
1778 the function. However, there's little else we can do.
1780 Also, by default, the typeinfo implementation assumes that
1781 there will be only one copy of the string used as the name for
1782 each type. Therefore, if weak symbols are unavailable, the
1783 run-time library should perform a more conservative check; it
1784 should perform a string comparison, rather than an address
1785 comparison. */
1787 else
1788 {
1789 /* Static data member template instantiations, however, cannot
1790 have multiple copies. */
1795 {
1798 }
1800 {
1801 /* We can't do anything useful; leave vars for explicit
1802 instantiation. */
1805 }
1806 }
1809 }
1811 /* For win32 we also want to put explicit instantiations in
1812 linkonce sections, so that they will be merged with implicit
1813 instantiations; otherwise we get duplicate symbol errors.
1814 For Darwin we do not want explicit instantiations to be
1815 linkonce. */
1817 void
1819 {
1820 /* We used to say that this was not necessary on targets that support weak
1821 symbols, because the implicit instantiations will defer to the explicit
1822 one. However, that's not actually the case in SVR4; a strong definition
1823 after a weak one is an error. Also, not making explicit
1824 instantiations one_only means that we can end up with two copies of
1825 some template instantiations. */
1829 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1830 we can get away with not emitting them if they aren't used. We need
1831 to for variables so that cp_finish_decl will update their linkage,
1832 because their DECL_INITIAL may not have been set properly yet. */
1837 {
1841 {
1844 /* Mark it needed so we don't forget to emit it. */
1847 }
1848 }
1849 }
1851 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1852 This predicate will give the right answer during parsing of the
1853 function, which other tests may not. */
1855 bool
1857 {
1858 /* Unfortunately, import_export_decl has not always been called
1859 before the function is processed, so we cannot simply check
1860 DECL_COMDAT. */
1869 /* A local static in an inline effectively has vague linkage. */
1872 else
1874 }
1876 /* Determine whether or not we want to specifically import or export CTYPE,
1877 using various heuristics. */
1879 static void
1881 {
1882 /* -1 for imported, 1 for exported. */
1885 /* It only makes sense to call this function at EOF. The reason is
1886 that this function looks at whether or not the first non-inline
1887 non-abstract virtual member function has been defined in this
1888 translation unit. But, we can't possibly know that until we've
1889 seen the entire translation unit. */
1895 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1896 we will have CLASSTYPE_INTERFACE_ONLY set but not
1897 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1898 heuristic because someone will supply a #pragma implementation
1899 elsewhere, and deducing it here would produce a conflict. */
1909 /* For a template class, without -fimplicit-templates, check the
1910 repository. If the virtual table is assigned to this
1911 translation unit, then export the class; otherwise, import
1912 it. */
1915 {
1916 /* The ABI specifies that the virtual table and associated
1917 information are emitted with the key method, if any. */
1919 /* If weak symbol support is not available, then we must be
1920 careful not to emit the vtable when the key function is
1921 inline. An inline function can be defined in multiple
1922 translation units. If we were to emit the vtable in each
1923 translation unit containing a definition, we would get
1924 multiple definition errors at link-time. */
1927 }
1929 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1930 a definition anywhere else. */
1934 /* Allow back ends the chance to overrule the decision. */
1939 {
1942 }
1943 }
1945 /* Return true if VAR has already been provided to the back end; in that
1946 case VAR should not be modified further by the front end. */
1947 static bool
1949 {
1951 }
1953 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1954 must be emitted in this translation unit. Mark it as such. */
1956 void
1958 {
1961 {
1962 /* Extern inline functions don't become needed when referenced.
1963 If we know a method will be emitted in other TU and no new
1964 functions can be marked reachable, just use the external
1965 definition. */
1969 /* #pragma interface and -frepo code can call mark_needed for
1970 maybe-in-charge 'tors; mark the clones as well. */
1971 tree clone;
1974 }
1976 {
1978 /* C++ frontend use mark_decl_references to force COMDAT variables
1979 to be output that might appear dead otherwise. */
1981 }
1982 }
1984 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
1985 returns true if a definition of this entity should be provided in
1986 this object file. Callers use this function to determine whether
1987 or not to let the back end know that a definition of DECL is
1988 available in this translation unit. */
1990 bool
1992 {
1994 /* This function should only be called at the end of the translation
1995 unit. We cannot be sure of whether or not something will be
1996 COMDAT until that point. */
1999 /* All entities with external linkage that are not COMDAT should be
2000 emitted; they may be referred to from other object files. */
2003 /* If this entity was used, let the back end see it; it will decide
2004 whether or not to emit it into the object file. */
2007 /* Functions marked "dllexport" must be emitted so that they are
2008 visible to other DLLs. */
2012 /* Virtual functions might be needed for devirtualization. */
2017 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
2018 reference to DECL might cause it to be emitted later. */
2020 }
2022 /* If necessary, write out the vtables for the dynamic class CTYPE.
2023 Returns true if any vtables were emitted. */
2025 static bool
2027 {
2028 tree vtbl;
2029 tree primary_vtbl;
2033 /* If the vtables for this class have already been emitted there is
2034 nothing more to do. */
2038 /* Ignore dummy vtables made by get_vtable_decl. */
2042 /* On some targets, we cannot determine the key method until the end
2043 of the translation unit -- which is when this function is
2044 called. */
2048 /* See if any of the vtables are needed. */
2050 {
2054 }
2056 {
2057 /* If the references to this class' vtables are optimized away,
2058 still emit the appropriate debugging information. See
2059 dfs_debug_mark. */
2064 }
2066 /* The ABI requires that we emit all of the vtables if we emit any
2067 of them. */
2069 {
2070 /* Mark entities references from the virtual table as used. */
2074 {
2077 LOOKUP_NORMAL);
2079 /* It had better be all done at compile-time. */
2081 }
2083 /* Write it out. */
2087 /* Because we're only doing syntax-checking, we'll never end up
2088 actually marking the variable as written. */
2092 {
2097 }
2098 }
2100 /* Since we're writing out the vtable here, also write the debug
2101 info. */
2105 }
2107 /* A special return value from type_visibility meaning internal
2108 linkage. */
2112 /* walk_tree helper function for type_visibility. */
2114 static tree
2116 {
2119 {
2121 }
2124 {
2127 }
2132 }
2134 /* Returns the visibility of TYPE, which is the minimum visibility of its
2135 component types. */
2137 static int
2139 {
2143 }
2145 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2146 specified (or if VISIBILITY is static). If TMPL is true, this
2147 constraint is for a template argument, and takes precedence
2148 over explicitly-specified visibility on the template. */
2150 static void
2152 {
2154 {
2155 /* extern "C" declarations aren't affected by the anonymous
2156 namespace. */
2158 {
2164 {
2169 }
2173 }
2174 }
2177 {
2179 /* This visibility was not specified. */
2181 }
2182 }
2184 /* Constrain the visibility of DECL based on the visibility of its template
2185 arguments. */
2187 static void
2189 {
2190 /* If this is a template instantiation, check the innermost
2191 template args for visibility constraints. The outer template
2192 args are covered by the class check. */
2196 {
2203 {
2208 {
2211 else
2213 }
2214 }
2217 }
2218 }
2220 /* Like c_determine_visibility, but with additional C++-specific
2221 behavior.
2223 Function-scope entities can rely on the function's visibility because
2224 it is set in start_preparsed_function.
2226 Class-scope entities cannot rely on the class's visibility until the end
2227 of the enclosing class definition.
2229 Note that because namespaces have multiple independent definitions,
2230 namespace visibility is handled elsewhere using the #pragma visibility
2231 machinery rather than by decorating the namespace declaration.
2233 The goal is for constraints from the type to give a diagnostic, and
2234 other constraints to be applied silently. */
2236 void
2238 {
2244 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2246 /* Only relevant for names with external linkage. */
2250 /* Cloned constructors and destructors get the same visibility as
2251 the underlying function. That should be set up in
2252 maybe_clone_body. */
2259 {
2264 else
2266 }
2269 else
2272 /* If DECL is a member of a class, visibility specifiers on the
2273 class can influence the visibility of the DECL. */
2276 else
2277 {
2278 /* Not a class member. */
2280 /* Virtual tables have DECL_CONTEXT set to their associated class,
2281 so they are automatically handled above. */
2286 {
2287 /* Local statics and classes get the visibility of their
2288 containing function by default, except that
2289 -fvisibility-inlines-hidden doesn't affect them. */
2292 {
2296 }
2297 else
2298 {
2302 {
2306 }
2307 else
2308 {
2312 }
2313 }
2315 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2316 but have no TEMPLATE_INFO, so don't try to check it. */
2318 }
2321 {
2322 /* Under -fvisibility-ms-compat, types are visible by default,
2323 even though their contents aren't. */
2330 else
2332 }
2334 {
2335 /* tinfo visibility is based on the type it's for. */
2336 constrain_visibility
2339 /* Give the target a chance to override the visibility associated
2340 with DECL. */
2346 }
2348 /* Template instantiations and specializations get visibility based
2351 {
2354 else
2355 {
2356 /* Set default visibility to whatever the user supplied with
2357 #pragma GCC visibility or a namespace visibility attribute. */
2360 }
2361 }
2362 }
2365 {
2366 /* If the specialization doesn't specify visibility, use the
2367 visibility from the template. */
2377 {
2381 {
2385 else
2386 {
2390 }
2391 }
2394 /* Template argument visibility outweighs #pragma or namespace
2395 visibility, but not an explicit attribute. */
2397 {
2400 {
2401 /* A class template member with explicit visibility
2402 overrides the class visibility, so we need to apply
2403 all the levels of template args directly. */
2406 {
2409 }
2410 }
2412 /* Limit visibility based on its template arguments. */
2414 }
2415 }
2416 }
2422 /* Names in an anonymous namespace get internal linkage.
2423 This might change once we implement export. */
2426 {
2427 /* Propagate anonymity from type to decl. */
2432 }
2434 /* DR 757: A type without linkage shall not be used as the type of a
2435 variable or function with linkage, unless
2436 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2437 o the variable or function is not used (3.2 [basic.def.odr]) or is
2438 defined in the same translation unit.
2440 Since non-extern "C" decls need to be defined in the same
2441 translation unit, we can make the type internal. */
2444 /* If visibility changed and DECL already has DECL_RTL, ensure
2445 symbol flags are updated. */
2452 }
2454 /* By default, static data members and function members receive
2455 the visibility of their containing class. */
2457 static void
2459 {
2465 else
2466 {
2467 /* Default to the class visibility. */
2471 }
2473 /* Give the target a chance to override the visibility associated
2474 with DECL. */
2478 /* Construction virtual tables are not exported because
2479 they cannot be referred to from other object files;
2480 their name is not standardized by the ABI. */
2486 }
2488 /* Returns true iff DECL is an inline that should get hidden visibility
2489 because of -fvisibility-inlines-hidden. */
2491 static bool
2493 {
2495 /* Don't do this for inline templates; specializations might not be
2496 inline, and we don't want them to inherit the hidden
2497 visibility. We'll set it here for all inline instantiations. */
2498 && !processing_template_decl
2503 }
2505 /* Constrain the visibility of a class TYPE based on the visibility of its
2506 field types. Warn if any fields require lesser visibility. */
2508 void
2510 {
2511 tree binfo;
2512 tree t;
2521 /* Don't warn about visibility if the class has explicit visibility. */
2527 {
2532 {
2537 }
2544 }
2548 {
2552 {
2557 }
2563 }
2564 }
2566 /* Functions for adjusting the visibility of a tagged type and its nested
2567 types and declarations when it gets a name for linkage purposes from a
2568 typedef. */
2573 /* First reset the visibility of all the types. */
2575 static void
2577 {
2582 }
2583 static void
2585 {
2587 }
2589 /* Then reset the visibility of any static data members or member
2590 functions that use those types. */
2592 static void
2594 {
2603 }
2604 static void
2606 {
2608 {
2610 {
2615 }
2617 {
2623 }
2631 }
2632 }
2633 static void
2635 {
2637 }
2638 void
2640 {
2643 }
2645 /* Set up our initial idea of what the linkage of DECL should be. */
2647 void
2649 {
2651 /* We've already made a decision as to how this function will
2654 {
2657 {
2661 /* A non-template inline function with external linkage will
2662 always be COMDAT. As we must eventually determine the
2663 linkage of all functions, and as that causes writes to
2664 the data mapped in from the PCH file, it's advantageous
2665 to mark the functions at this point. */
2669 {
2670 /* This function must have external linkage, as
2671 otherwise DECL_INTERFACE_KNOWN would have been
2672 set. */
2676 }
2677 }
2680 }
2681 }
2683 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2684 for DECL has not already been determined, do so now by setting
2685 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2686 function is called entities with vague linkage whose definitions
2687 are available must have TREE_PUBLIC set.
2689 If this function decides to place DECL in COMDAT, it will set
2690 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2691 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2692 callers defer that decision until it is clear that DECL is actually
2693 required. */
2695 void
2697 {
2706 /* We cannot determine what linkage to give to an entity with vague
2707 linkage until the end of the file. For example, a virtual table
2708 for a class will be defined if and only if the key method is
2709 defined in this translation unit. As a further example, consider
2710 that when compiling a translation unit that uses PCH file with
2711 "-frepo" it would be incorrect to make decisions about what
2712 entities to emit when building the PCH; those decisions must be
2713 delayed until the repository information has been processed. */
2715 /* Object file linkage for explicit instantiations is handled in
2716 mark_decl_instantiated. For static variables in functions with
2717 vague linkage, maybe_commonize_var is used.
2719 Therefore, the only declarations that should be provided to this
2720 function are those with external linkage that are:
2722 * implicit instantiations of function templates
2724 * inline function
2726 * implicit instantiations of static data members of class
2727 templates
2729 * virtual tables
2731 * typeinfo objects
2733 Furthermore, all entities that reach this point must have a
2734 definition available in this translation unit.
2736 The following assertions check these conditions. */
2738 /* Any code that creates entities with TREE_PUBLIC cleared should
2739 also set DECL_INTERFACE_KNOWN. */
2745 else
2749 /* Check that a definition of DECL is available in this translation
2750 unit. */
2753 /* Assume that DECL will not have COMDAT linkage. */
2755 /* Assume that DECL will not be imported into this translation
2756 unit. */
2759 /* See if the repository tells us whether or not to emit DECL in
2760 this translation unit. */
2765 {
2766 /* The repository indicates that this entity should be defined
2767 here. Make sure the back end honors that request. */
2769 /* Output the definition as an ordinary strong definition. */
2773 }
2776 /* We have already decided what to do with this DECL; there is no
2777 need to check anything further. */
2778 ;
2780 {
2792 /* The ABI requires that all virtual tables be emitted with
2793 COMDAT linkage. However, on systems where COMDAT symbols
2794 don't show up in the table of contents for a static
2795 archive, or on systems without weak symbols (where we
2796 approximate COMDAT linkage by using internal linkage), the
2797 linker will report errors about undefined symbols because
2798 it will not see the virtual table definition. Therefore,
2799 in the case that we know that the virtual table will be
2800 emitted in only one translation unit, we make the virtual
2801 table an ordinary definition with external linkage. */
2804 {
2805 /* CLASS_TYPE is being exported from this translation unit,
2806 so DECL should be defined here. */
2808 /* If a class is declared in a header with the "extern
2809 template" extension, then it will not be instantiated,
2810 even in translation units that would normally require
2811 it. Often such classes are explicitly instantiated in
2812 one translation unit. Therefore, the explicit
2813 instantiation must be made visible to other translation
2814 units. */
2816 else
2817 {
2818 /* The generic C++ ABI says that class data is always
2819 COMDAT, even if there is a key function. Some
2820 variants (e.g., the ARM EABI) says that class data
2821 only has COMDAT linkage if the class data might be
2822 emitted in more than one translation unit. When the
2823 key method can be inline and is inline, we still have
2824 to arrange for comdat even though
2825 class_data_always_comdat is false. */
2829 {
2830 /* The ABI requires COMDAT linkage. Normally, we
2831 only emit COMDAT things when they are needed;
2832 make sure that we realize that this entity is
2833 indeed needed. */
2836 }
2837 }
2838 }
2842 else
2844 }
2846 {
2849 {
2855 /* If -fno-rtti was specified, then we cannot be sure
2856 that RTTI information will be emitted with the
2857 virtual table of the class, so we must emit it
2858 wherever it is used. */
2861 else
2862 {
2865 {
2871 {
2874 }
2875 }
2876 else
2878 }
2879 }
2880 else
2882 }
2884 {
2885 /* DECL is an implicit instantiation of a function or static
2886 data member. */
2889 || (flag_implicit_inline_templates
2893 else
2894 /* If we are not implicitly generating templates, then mark
2895 this entity as undefined in this translation unit. */
2897 }
2899 {
2901 {
2905 {
2909 && ! flag_implement_inlines
2915 /* Always make artificials weak. */
2918 else
2920 }
2921 }
2922 else
2924 }
2925 else
2929 {
2930 /* If we are importing DECL into this translation unit, mark is
2931 an undefined here. */
2934 }
2936 {
2937 /* If we decided to put DECL in COMDAT, mark it accordingly at
2938 this point. */
2940 }
2943 }
2945 /* Return an expression that performs the destruction of DECL, which
2946 must be a VAR_DECL whose type has a non-trivial destructor, or is
2947 an array whose (innermost) elements have a non-trivial destructor. */
2949 tree
2951 {
2955 }
2957 /* Returns the initialization guard variable for the variable DECL,
2958 which has static storage duration. */
2960 tree
2962 {
2963 tree sname;
2964 tree guard;
2969 {
2970 tree guard_type;
2972 /* We use a type that is big enough to contain a mutex as well
2973 as an integer counter. */
2978 /* The guard should have the same linkage as what it guards. */
2995 }
2997 }
2999 /* Return those bits of the GUARD variable that should be set when the
3000 guarded entity is actually initialized. */
3002 static tree
3004 {
3006 {
3007 /* We only set the first byte of the guard, in order to leave room
3008 for a mutex in the high-order bits. */
3011 guard);
3014 guard);
3016 }
3019 }
3021 /* Return an expression which determines whether or not the GUARD
3022 variable has already been initialized. */
3024 tree
3026 {
3027 tree guard_value;
3029 /* Check to see if the GUARD is zero. */
3032 /* Mask off all but the low bit. */
3034 {
3040 tf_warning_or_error);
3041 }
3048 tf_warning_or_error);
3049 }
3051 /* Return an expression which sets the GUARD variable, indicating that
3052 the variable being guarded has been initialized. */
3054 tree
3056 {
3057 tree guard_init;
3059 /* Set the GUARD to one. */
3065 tf_warning_or_error);
3066 }
3068 /* Returns true iff we can tell that VAR does not have a dynamic
3069 initializer. */
3071 static bool
3073 {
3074 /* If it's defined in another TU, we can't tell. */
3077 /* If it has a non-trivial destructor, registering the destructor
3078 counts as dynamic initialization. */
3081 /* If it's in this TU, its initializer has been processed. */
3083 /* If it has no initializer or a constant one, it's not dynamic. */
3086 }
3088 /* Returns true iff VAR is a variable that needs uses to be
3089 wrapped for possible dynamic initialization. */
3091 static bool
3093 {
3099 }
3101 /* Get the FUNCTION_DECL for the shared TLS init function for this
3102 translation unit. */
3104 static tree
3106 {
3110 {
3113 void_list_node));
3119 }
3121 }
3123 /* Get a FUNCTION_DECL for the init function for the thread_local
3124 variable VAR. The init function will be an alias to the function
3125 that initializes all the non-local TLS variables in the translation
3126 unit. The init function is only used by the wrapper function. */
3128 static tree
3130 {
3131 /* Only C++11 TLS vars need this init fn. */
3135 /* If -fno-extern-tls-init, assume that we don't need to call
3136 a tls init function for a variable defined in another TU. */
3140 #ifdef ASM_OUTPUT_DEF
3141 /* If the variable is internal, or if we can't generate aliases,
3142 call the local init function directly. */
3144 #endif
3150 {
3153 void_list_node));
3162 {
3164 /* If the variable is defined somewhere else and might have static
3165 initialization, make the init function a weak reference. */
3171 else
3173 }
3183 }
3185 }
3187 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3188 variable VAR. The wrapper function calls the init function (if any) for
3189 VAR and then returns a reference to VAR. The wrapper function is used
3190 in place of VAR everywhere VAR is mentioned. */
3192 tree
3194 {
3195 /* Only C++11 TLS vars need this wrapper fn. */
3202 {
3203 /* A named rvalue reference is an lvalue, so the wrapper should
3204 always return an lvalue reference. */
3213 /* The wrapper is inline and emitted everywhere var is used. */
3216 {
3218 #ifdef HAVE_GAS_HIDDEN
3219 /* Make the wrapper bind locally; there's no reason to share
3220 the wrapper between multiple shared objects. */
3223 #endif
3224 }
3230 #if 0
3231 /* We want CSE to commonize calls to the wrapper, but marking it as
3232 pure is unsafe since it has side-effects. I guess we need a new
3233 ECF flag even weaker than ECF_PURE. FIXME! */
3235 #endif
3240 }
3242 }
3244 /* At EOF, generate the definition for the TLS wrapper function FN:
3246 T& var_wrapper() {
3247 if (init_fn) init_fn();
3248 return var;
3249 } */
3251 static void
3253 {
3258 /* Only call the init fn if there might be one. */
3260 {
3262 /* If init_fn is a weakref, make sure it exists before calling. */
3264 {
3269 tf_warning_or_error);
3271 }
3275 {
3278 }
3279 }
3280 else
3281 /* If there's no initialization, the wrapper is a constant function. */
3286 }
3288 /* Start the process of running a particular set of global constructors
3289 or destructors. Subroutine of do_[cd]tors. Also called from
3290 vtv_start_verification_constructor_init_function. */
3292 static tree
3294 {
3295 tree body;
3296 tree fndecl;
3299 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3302 {
3305 #ifdef JOINER
3307 #else
3309 #endif
3312 }
3313 else
3319 NULL_TREE));
3324 /* Mark as artificial because it's not explicitly in the user's
3325 source code. */
3328 /* Mark this declaration as used to avoid spurious warnings. */
3331 /* Mark this function as a global constructor or destructor. */
3334 else
3340 }
3342 /* Finish the process of running a particular set of global constructors
3343 or destructors. Subroutine of do_[cd]tors. */
3345 static void
3347 {
3348 tree fn;
3350 /* Finish up. */
3355 {
3358 }
3359 else
3360 {
3363 }
3366 }
3368 /* The names of the parameters to the function created to handle
3369 initializations and destructions for objects with static storage
3370 duration. */
3374 /* The name of the function we create to handle initializations and
3375 destructions for objects with static storage duration. */
3378 /* The declaration for the __INITIALIZE_P argument. */
3381 /* The declaration for the __PRIORITY argument. */
3384 /* The declaration for the static storage duration function. */
3387 /* All the static storage duration functions created in this
3388 translation unit. */
3391 /* A map from priority levels to information about that priority
3392 level. There may be many such levels, so efficient lookup is
3393 important. */
3396 /* Begins the generation of the function that will handle all
3397 initialization and destruction of objects with static storage
3398 duration. The function generated takes two parameters of type
3399 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3400 nonzero, it performs initializations. Otherwise, it performs
3401 destructions. It only performs those initializations or
3402 destructions with the indicated __PRIORITY. The generated function
3403 returns no value.
3405 It is assumed that this function will only be called once per
3406 translation unit. */
3408 static tree
3410 {
3411 tree type;
3412 tree body;
3415 /* Create the identifier for this function. It will be of the form
3416 SSDF_IDENTIFIER_<number>. */
3421 NULL_TREE);
3423 /* Create the FUNCTION_DECL itself. */
3426 type);
3430 /* Put this function in the list of functions to be called from the
3431 static constructors and destructors. */
3433 {
3436 /* Take this opportunity to initialize the map from priority
3437 numbers to information about that priority level. */
3440 /*delete_value_fn=*/
3443 /* We always need to generate functions for the
3444 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3445 priorities later, we'll be sure to find the
3446 DEFAULT_INIT_PRIORITY. */
3448 }
3452 /* Create the argument list. */
3453 initialize_p_decl = cp_build_parm_decl
3457 priority_decl = cp_build_parm_decl
3465 /* Put the function in the global scope. */
3468 /* Start the function itself. This is equivalent to declaring the
3469 function as:
3471 static void __ssdf (int __initialize_p, init __priority_p);
3473 It is static because we only need to call this function from the
3474 various constructor and destructor functions for this module. */
3477 SF_PRE_PARSED);
3479 /* Set up the scope of the outermost block in the function. */
3483 }
3485 /* Finish the generation of the function which performs initialization
3486 and destruction of objects with static storage duration. After
3487 this point, no more such objects can be created. */
3489 static void
3491 {
3492 /* Close out the function. */
3495 }
3497 /* Return the information about the indicated PRIORITY level. If no
3498 code to handle this level has yet been generated, generate the
3499 appropriate prologue. */
3501 static priority_info
3503 {
3504 priority_info pi;
3505 splay_tree_node n;
3510 {
3511 /* Create a new priority information structure, and insert it
3512 into the map. */
3519 }
3520 else
3524 }
3526 /* The effective initialization priority of a DECL. */
3528 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3529 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3530 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3532 /* Whether a DECL needs a guard to protect it against multiple
3533 initialization. */
3535 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3536 || DECL_ONE_ONLY (decl) \
3537 || DECL_WEAK (decl)))
3539 /* Called from one_static_initialization_or_destruction(),
3540 via walk_tree.
3541 Walks the initializer list of a global variable and looks for
3542 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3543 and that have their DECL_CONTEXT() == NULL.
3544 For each such temporary variable, set their DECL_CONTEXT() to
3545 the current function. This is necessary because otherwise
3546 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3547 when trying to refer to a temporary variable that does not have
3548 it's DECL_CONTECT() properly set. */
3549 static tree
3553 {
3557 {
3558 tree var;
3566 }
3569 }
3571 /* Set up to handle the initialization or destruction of DECL. If
3572 INITP is nonzero, we are initializing the variable. Otherwise, we
3573 are destroying it. */
3575 static void
3577 {
3579 tree guard;
3581 /* If we are supposed to destruct and there's a trivial destructor,
3582 nothing has to be done. */
3587 /* Trick the compiler into thinking we are at the file and line
3588 where DECL was declared so that error-messages make sense, and so
3589 that the debugger will show somewhat sensible file and line
3590 information. */
3593 /* Make sure temporary variables in the initialiser all have
3594 their DECL_CONTEXT() set to a value different from NULL_TREE.
3595 This can happen when global variables initialisers are built.
3596 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3597 the temporary variables that might have been generated in the
3598 accompagning initialisers is NULL_TREE, meaning the variables have been
3599 declared in the global namespace.
3600 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3601 of the temporaries are set to the current function decl. */
3603 fix_temporary_vars_context_r,
3604 NULL);
3606 /* Because of:
3608 [class.access.spec]
3610 Access control for implicit calls to the constructors,
3611 the conversion functions, or the destructor called to
3612 create and destroy a static data member is performed as
3613 if these calls appeared in the scope of the member's
3614 class.
3616 we pretend we are in a static member function of the class of
3617 which the DECL is a member. */
3619 {
3622 }
3624 /* Assume we don't need a guard. */
3626 /* We need a guard if this is an object with external linkage that
3627 might be initialized in more than one place. (For example, a
3628 static data member of a template, when the data member requires
3629 construction.) */
3631 {
3632 tree guard_cond;
3636 /* When using __cxa_atexit, we just check the GUARD as we would
3637 for a local static. */
3639 {
3640 /* When using __cxa_atexit, we never try to destroy
3641 anything from a static destructor. */
3644 }
3645 /* If we don't have __cxa_atexit, then we will be running
3646 destructors from .fini sections, or their equivalents. So,
3647 we need to know how many times we've tried to initialize this
3648 object. We do initializations only if the GUARD is zero,
3649 i.e., if we are the first to initialize the variable. We do
3650 destructions only if the GUARD is one, i.e., if we are the
3651 last to destroy the variable. */
3653 guard_cond
3655 EQ_EXPR,
3657 guard,
3659 tf_warning_or_error),
3660 integer_one_node,
3661 tf_warning_or_error);
3662 else
3663 guard_cond
3665 EQ_EXPR,
3667 guard,
3669 tf_warning_or_error),
3670 integer_zero_node,
3671 tf_warning_or_error);
3675 }
3678 /* If we're using __cxa_atexit, we have not already set the GUARD,
3679 so we must do so now. */
3683 /* Perform the initialization or destruction. */
3685 {
3687 {
3690 {
3694 }
3695 }
3697 /* If we're using __cxa_atexit, register a function that calls the
3698 destructor for the object. */
3701 }
3702 else
3705 /* Finish the guard if-stmt, if necessary. */
3707 {
3710 }
3712 /* Now that we're done with DECL we don't need to pretend to be a
3713 member of its class any longer. */
3716 }
3718 /* Generate code to do the initialization or destruction of the decls in VARS,
3719 a TREE_LIST of VAR_DECL with static storage duration.
3720 Whether initialization or destruction is performed is specified by INITP. */
3722 static void
3724 {
3727 /* Build the outer if-stmt to check for initialization or destruction. */
3731 EQ_EXPR,
3732 initialize_p_decl,
3733 cond,
3734 tf_warning_or_error);
3737 /* To make sure dynamic construction doesn't access globals from other
3738 compilation units where they might not be yet constructed, for
3739 -fsanitize=address insert __asan_before_dynamic_init call that
3740 prevents access to either all global variables that need construction
3741 in other compilation units, or at least those that haven't been
3742 initialized yet. Variables that need dynamic construction in
3743 the current compilation unit are kept accessible. */
3750 tree priority_if_stmt;
3752 priority_info pi;
3754 /* If we don't need a destructor, there's nothing to do. Avoid
3755 creating a possibly empty if-stmt. */
3757 {
3760 }
3762 /* Remember that we had an initialization or finalization at this
3763 priority. */
3768 else
3771 /* Conditionalize this initialization on being in the right priority
3772 and being initializing/finalizing appropriately. */
3775 EQ_EXPR,
3776 priority_decl,
3778 tf_warning_or_error);
3781 /* Process initializers with same priority. */
3785 /* Do one initialization or destruction. */
3789 /* Finish up the priority if-stmt body. */
3795 /* Revert what __asan_before_dynamic_init did by calling
3796 __asan_after_dynamic_init. */
3800 /* Finish up the init/destruct if-stmt body. */
3803 }
3805 /* VARS is a list of variables with static storage duration which may
3806 need initialization and/or finalization. Remove those variables
3807 that don't really need to be initialized or finalized, and return
3808 the resulting list. The order in which the variables appear in
3809 VARS is in reverse order of the order in which they should actually
3810 be initialized. The list we return is in the unreversed order;
3811 i.e., the first variable should be initialized first. */
3813 static tree
3815 {
3820 {
3825 /* Deal gracefully with error. */
3827 {
3830 }
3832 /* The only things that can be initialized are variables. */
3835 /* If this object is not defined, we don't need to do anything
3836 here. */
3838 {
3841 }
3843 /* Also, if the initializer already contains errors, we can bail
3844 out now. */
3847 {
3850 }
3852 /* This variable is going to need initialization and/or
3853 finalization, so we add it to the list. */
3857 }
3860 }
3862 /* Make sure we have told the back end about all the variables in
3863 VARS. */
3865 static void
3867 {
3868 tree v;
3871 {
3874 {
3877 }
3878 }
3879 }
3881 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
3882 (otherwise) that will initialize all global objects with static
3883 storage duration having the indicated PRIORITY. */
3885 static void
3888 {
3890 tree fndecl;
3891 tree body;
3895 /* ??? */
3896 /* Was: locus->line++; */
3898 /* We use `I' to indicate initialization and `D' to indicate
3899 destruction. */
3902 /* We emit the function lazily, to avoid generating empty
3903 global constructors and destructors. */
3906 /* For Objective-C++, we may need to initialize metadata found in this module.
3907 This must be done _before_ any other static initializations. */
3910 {
3913 }
3915 /* Call the static storage duration function with appropriate
3916 arguments. */
3918 {
3919 /* Calls to pure or const functions will expand to nothing. */
3921 {
3922 tree call;
3929 constructor_p),
3931 priority),
3932 NULL_TREE);
3934 }
3935 }
3937 /* Close out the function. */
3940 }
3942 /* Generate constructor and destructor functions for the priority
3943 indicated by N. */
3945 static int
3947 {
3952 /* Generate the functions themselves, but only if they are really
3953 needed. */
3959 /* Keep iterating. */
3961 }
3963 /* Java requires that we be able to reference a local address for a
3964 method, and not be confused by PLT entries. If hidden aliases are
3965 supported, collect and return all the functions for which we should
3966 emit a hidden alias. */
3970 {
3974 #ifndef HAVE_GAS_HIDDEN
3976 #endif
3979 {
3985 {
3989 }
3990 }
3993 }
3996 /* Java requires that we be able to reference a local address for a
3997 method, and not be confused by PLT entries. If hidden aliases are
3998 supported, emit one for each java function that we've emitted.
3999 CANDIDATES is the set of FUNCTION_DECLs that were gathered
4000 by collect_candidates_for_java_method_aliases. */
4002 static void
4004 {
4007 #ifndef HAVE_GAS_HIDDEN
4009 #endif
4012 {
4017 {
4018 /* Mangle the name in a predictable way; we need to reference
4019 this from a java compiled object file. */
4035 }
4036 }
4037 }
4039 /* Return C++ property of T, based on given operation OP. */
4041 static int
4043 {
4045 {
4060 }
4061 }
4063 /* Collect source file references recursively, starting from NAMESPC. */
4065 static void
4067 {
4068 tree t;
4073 /* Iterate over names in this name space. */
4078 /* Dump siblings, if any */
4081 /* Dump children, if any */
4083 }
4085 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4086 starting from NAMESPC. */
4088 static void
4090 {
4094 /* Collect decls from this namespace */
4097 /* Collect siblings, if any */
4100 /* Collect children, if any */
4102 }
4104 /* Returns true iff there is a definition available for variable or
4105 function DECL. */
4107 static bool
4109 {
4112 else
4113 {
4116 }
4117 }
4119 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4121 [expr.const]
4123 An integral constant-expression can only involve ... const
4124 variables of integral or enumeration types initialized with
4125 constant expressions ...
4127 C++0x also allows constexpr variables and temporaries initialized
4128 with constant expressions. We handle the former here, but the latter
4129 are just folded away in cxx_eval_constant_expression.
4131 The standard does not require that the expression be non-volatile.
4132 G++ implements the proposed correction in DR 457. */
4134 bool
4136 {
4140 /* We don't know if a template static data member is initialized with
4141 a constant expression until we instantiate its initializer. Even
4142 in the case of a constexpr variable, we can't treat it as a
4143 constant until its initializer is complete in case it's used in
4144 its own initializer. */
4147 }
4149 /* Returns true if DECL could be a symbolic constant variable, depending on
4150 its initializer. */
4152 bool
4154 {
4162 }
4164 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4165 called from grokfndecl and grokvardecl; in all modes it is called from
4166 cp_write_global_declarations. */
4168 void
4170 {
4172 /* In C++11 it's ok if the decl is defined. */
4176 /* The type that got us on no_linkage_decls must have gotten a name for
4179 /* The type might end up having a typedef name for linkage purposes. */
4182 {
4190 /* DRs 132, 319 and 389 seem to indicate types with
4191 no linkage can only be used to declare extern "C"
4192 entities. Since it's not always an error in the
4193 ISO C++ 90 Standard, we only issue a warning. */
4195 "with no linkage used to declare variable %q#D with "
4197 else
4200 decl);
4205 }
4212 else
4215 }
4217 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4219 static void
4221 {
4223 }
4225 /* Clear DECL_EXTERNAL for NODE. */
4227 static bool
4229 {
4232 }
4234 /* Build up the function to run dynamic initializers for thread_local
4235 variables in this translation unit and alias the init functions for the
4236 individual variables to it. */
4238 static void
4240 {
4250 boolean_type_node);
4264 tf_warning_or_error);
4267 tf_warning_or_error));
4269 {
4274 #ifdef ASM_OUTPUT_DEF
4275 /* Output init aliases even with -fno-extern-tls-init. */
4277 {
4281 cgraph_node *alias
4285 }
4286 #endif
4287 }
4293 }
4295 /* The entire file is now complete. If requested, dump everything
4296 to a file. */
4298 static void
4300 {
4305 {
4308 }
4309 }
4311 /* Check the deallocation functions for CODE to see if we want to warn that
4312 only one was defined. */
4314 static void
4316 {
4322 {
4324 /* We're only interested in usual deallocation functions. */
4329 else
4331 }
4338 }
4340 /* Check the global deallocation functions to see if we want to warn about
4341 defining unsized without sized (or vice versa). */
4343 static void
4345 {
4350 }
4352 /* This routine is called at the end of compilation.
4353 Its job is to create all the code needed to initialize and
4354 destroy the global aggregates. We do the destruction
4355 first, since that way we only need to reverse the decls once. */
4357 void
4359 {
4360 tree vars;
4363 location_t locus;
4366 tree decl;
4372 /* Bad parse errors. Just forget about it. */
4377 /* This is the point to write out a PCH if we're doing that.
4378 In that case we do not want to do anything else. */
4380 {
4384 }
4388 /* Handle -fdump-ada-spec[-slim] */
4390 {
4393 else
4397 }
4399 /* FIXME - huh? was input_line -= 1;*/
4403 /* We now have to write out all the stuff we put off writing out.
4404 These include:
4406 o Template specializations that we have not yet instantiated,
4407 but which are needed.
4408 o Initialization and destruction for non-local objects with
4409 static storage duration. (Local objects with static storage
4410 duration are initialized when their scope is first entered,
4411 and are cleaned up via atexit.)
4412 o Virtual function tables.
4414 All of these may cause others to be needed. For example,
4415 instantiating one function may cause another to be needed, and
4416 generating the initializer for an object may cause templates to be
4417 instantiated, etc., etc. */
4421 do
4422 {
4423 tree t;
4424 tree decl;
4428 /* If there are templates that we've put off instantiating, do
4429 them now. */
4433 /* Write out virtual tables as required. Note that writing out
4434 the virtual table for a template class may cause the
4435 instantiation of members of that class. If we write out
4436 vtables then we remove the class from our list so we don't
4437 have to look at it again. */
4441 {
4444 }
4448 {
4452 {
4454 {
4457 }
4458 else
4462 }
4463 }
4465 /* Write out needed type info variables. We have to be careful
4466 looping through unemitted decls, because emit_tinfo_decl may
4467 cause other variables to be needed. New elements will be
4468 appended, and we remove from the vector those that actually
4469 get emitted. */
4473 {
4476 }
4478 /* The list of objects with static storage duration is built up
4479 in reverse order. We clear STATIC_AGGREGATES so that any new
4480 aggregates added during the initialization of these will be
4481 initialized in the correct order when we next come around the
4482 loop. */
4486 {
4487 /* We need to start a new initialization function each time
4488 through the loop. That's because we need to know which
4489 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4490 isn't computed until a function is finished, and written
4491 out. That's a deficiency in the back end. When this is
4492 fixed, these initialization functions could all become
4493 inline, with resulting performance improvements. */
4494 tree ssdf_body;
4496 /* Set the line and file, so that it is obviously not from
4497 the source file. */
4501 /* Make sure the back end knows about all the variables. */
4504 /* First generate code to do all the initializations. */
4508 /* Then, generate code to do all the destructions. Do these
4509 in reverse order so that the most recently constructed
4510 variable is the first destroyed. If we're using
4511 __cxa_atexit, then we don't need to do this; functions
4512 were registered at initialization time to destroy the
4513 local statics. */
4515 {
4518 }
4519 else
4522 /* Finish up the static storage duration function for this
4523 round. */
4527 /* All those initializations and finalizations might cause
4528 us to need more inline functions, more template
4529 instantiations, etc. */
4531 ssdf_count++;
4532 /* ??? was: locus.line++; */
4533 }
4535 /* Now do the same for thread_local variables. */
4538 /* Go through the set of inline functions whose bodies have not
4539 been emitted yet. If out-of-line copies of these functions
4540 are required, emit them. */
4542 {
4543 /* Does it need synthesizing? */
4546 {
4547 /* Even though we're already at the top-level, we push
4548 there again. That way, when we pop back a few lines
4549 hence, all of our state is restored. Otherwise,
4550 finish_function doesn't clean things up, and we end
4551 up with CURRENT_FUNCTION_DECL set. */
4553 /* The decl's location will mark where it was first
4554 needed. Save that so synthesize method can indicate
4555 where it was needed from, in case of error */
4560 }
4568 /* We lie to the back end, pretending that some functions
4569 are not defined when they really are. This keeps these
4570 functions from being put out unnecessarily. But, we must
4571 stop lying when the functions are referenced, or if they
4572 are not comdat since they need to be put out now. If
4573 DECL_INTERFACE_KNOWN, then we have already set
4574 DECL_EXTERNAL appropriately, so there's no need to check
4575 again, and we do not want to clear DECL_EXTERNAL if a
4576 previous call to import_export_decl set it.
4578 This is done in a separate for cycle, because if some
4579 deferred function is contained in another deferred
4580 function later in deferred_fns varray,
4581 rest_of_compilation would skip this function and we
4582 really cannot expand the same function twice. */
4587 {
4596 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4597 group, we need to mark all symbols in the same comdat group
4598 that way. */
4605 }
4607 /* If we're going to need to write this function out, and
4608 there's already a body for it, create RTL for it now.
4609 (There might be no body if this is a method we haven't
4610 gotten around to synthesizing yet.) */
4615 {
4616 /* We will output the function; no longer consider it in this
4617 loop. */
4619 /* Generate RTL for this function now that we know we
4620 need it. */
4622 /* If we're compiling -fsyntax-only pretend that this
4623 function has been written out so that we don't try to
4624 expand it again. */
4628 }
4629 }
4634 /* Static data members are just like namespace-scope globals. */
4636 {
4638 /* Don't write it out if we haven't seen a definition. */
4642 /* If this static data member is needed, provide it to the
4643 back end. */
4646 }
4652 retries++;
4653 }
4656 /* All used inline functions must have a definition at this point. */
4658 {
4661 /* If the definition actually was available here, then the
4662 fact that the function was not defined merely represents
4663 that for some reason (use of a template repository,
4664 #pragma interface, etc.) we decided not to emit the
4665 definition here. */
4667 /* Don't complain if the template was defined. */
4671 {
4673 /* Avoid a duplicate warning from check_global_declaration_1. */
4675 }
4676 }
4678 /* So must decls that use a type with no linkage. */
4684 /* Then, do the Objective-C stuff. This is where all the
4685 Objective-C module stuff gets generated (symtab,
4686 class/protocol/selector lists etc). This must be done after C++
4687 templates, destructors etc. so that selectors used in C++
4688 templates are properly allocated. */
4692 /* We give C linkage to static constructors and destructors. */
4695 /* Generate initialization and destruction functions for all
4696 priorities for which they are required. */
4699 generate_ctor_and_dtor_functions_for_priority,
4702 /* If this is obj-c++ and we need a static init, call
4703 generate_ctor_or_dtor_function. */
4707 /* We're done with the splay-tree now. */
4711 /* Generate any missing aliases. */
4714 /* We're done with static constructors, so we can go back to "C++"
4715 linkage now. */
4718 /* Collect candidates for Java hidden aliases. */
4725 {
4729 }
4734 {
4735 /* Generate the special constructor initialization function that
4736 calls __VLTRegisterPairs, and give it a very high
4737 initialization priority. This must be done after
4738 finalize_compilation_unit so that we have accurate
4739 information about which vtable will actually be emitted. */
4741 }
4746 /* Now, issue warnings about static, but not defined, functions,
4747 etc., and emit debugging information. */
4750 {
4755 }
4759 /* Generate hidden aliases for Java. */
4761 {
4764 }
4768 /* The entire file is now complete. If requested, dump everything
4769 to a file. */
4773 {
4776 }
4779 #ifdef ENABLE_CHECKING
4784 }
4786 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
4787 function to call in parse-tree form; it has not yet been
4788 semantically analyzed. ARGS are the arguments to the function.
4789 They have already been semantically analyzed. This may change
4790 ARGS. */
4792 tree
4794 tsubst_flags_t complain)
4795 {
4796 tree orig_fn;
4798 tree expr;
4799 tree object;
4805 {
4814 /* Transform the arguments and add the implicit "this"
4815 parameter. That must be done before the FN is transformed
4816 because we depend on the form of FN. */
4820 {
4824 }
4825 /* Now that the arguments are done, transform FN. */
4827 }
4829 /* A qualified name corresponding to a bound pointer-to-member is
4830 represented as an OFFSET_REF:
4832 struct B { void g(); };
4833 void (B::*p)();
4834 void B::g() { (this->*p)(); } */
4836 {
4840 complain);
4842 }
4846 else
4855 }
4858 void
4860 {
4865 {
4869 {
4872 }
4873 }
4874 }
4876 /* Return true if function DECL can be inlined. This is used to force
4877 instantiation of methods that might be interesting for inlining. */
4878 bool
4880 {
4886 /* When optimizing, we might inline everything when flatten
4887 attribute or heuristics inlining for size or autoinlining
4888 is used. */
4890 }
4892 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
4893 If DECL is a specialization or implicitly declared class member,
4894 generate the actual definition. Return false if something goes
4895 wrong, true otherwise. */
4897 bool
4899 {
4900 /* If DECL is a BASELINK for a single function, then treat it just
4901 like the DECL for the function. Otherwise, if the BASELINK is
4902 for an overloaded function, we don't know which function was
4903 actually used until after overload resolution. */
4905 {
4910 }
4912 /* Set TREE_USED for the benefit of -Wunused. */
4917 /* Mark enumeration types as used. */
4926 {
4928 {
4931 {
4932 /* We mark a lambda conversion op as deleted if we can't
4933 generate it properly; see maybe_add_lambda_conv_op. */
4937 }
4938 }
4940 {
4944 }
4946 }
4952 /* We can only check DECL_ODR_USED on variables or functions with
4953 DECL_LANG_SPECIFIC set, and these are also the only decls that we
4954 might need special handling for. */
4958 {
4960 {
4964 }
4966 }
4968 /* We only want to do this processing once. We don't need to keep trying
4969 to instantiate inline templates, because unit-at-a-time will make sure
4970 we get them compiled before functions that want to inline them. */
4974 /* If within finish_function, defer the rest until that function
4975 finishes, otherwise it might recurse. */
4977 {
4980 }
4982 /* Normally, we can wait until instantiation-time to synthesize DECL.
4983 However, if DECL is a static data member initialized with a constant
4984 or a constexpr function, we need it right now because a reference to
4985 such a data member or a call to such function is not value-dependent.
4986 For a function that uses auto in the return type, we need to instantiate
4987 it to find out its type. For OpenMP user defined reductions, we need
4988 them instantiated for reduction clauses which inline them by hand
4989 directly. */
4998 {
4999 /* Instantiating a function will result in garbage collection. We
5000 must treat this situation as if we were within the body of a
5001 function so as to avoid collecting live data only referenced from
5002 the stack (such as overload resolution candidates). */
5007 }
5012 /* Check this too in case we're within instantiate_non_dependent_expr. */
5019 /* If we don't need a value, then we don't need to synthesize DECL. */
5027 /* DR 757: A type without linkage shall not be used as the type of a
5028 variable or function with linkage, unless
5029 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5030 o the variable or function is not used (3.2 [basic.def.odr]) or is
5031 defined in the same translation unit. */
5038 {
5040 /* There's no way to define a local extern, and adding it to
5041 the vector interferes with GC, so give an error now. */
5043 else
5045 }
5049 /* Remember it, so we can check it was defined. */
5052 /* Is it a synthesized method that needs to be synthesized? */
5056 /* A function defaulted outside the class is synthesized either by
5057 cp_finish_decl or instantiate_decl. */
5060 {
5061 /* Defer virtual destructors so that thunks get the right
5062 linkage. */
5064 {
5067 }
5069 /* Remember the current location for a function we will end up
5070 synthesizing. Then we can inform the user where it was
5071 required in the case of error. */
5074 /* Synthesizing an implicitly defined member function will result in
5075 garbage collection. We must treat this situation as if we were
5076 within the body of a function so as to avoid collecting live data
5077 on the stack (such as overload resolution candidates).
5079 We could just let cp_write_global_declarations handle synthesizing
5080 this function by adding it to deferred_fns, but doing
5081 it at the use site produces better error messages. */
5085 /* If this is a synthesized method we don't need to
5086 do the instantiation test below. */
5087 }
5092 /* If this is a function or variable that is an instance of some
5093 template, we now know that we will need to actually do the
5094 instantiation. We check that DECL is not an explicit
5095 instantiation because that is not checked in instantiate_decl.
5097 We put off instantiating functions in order to improve compile
5098 times. Maintaining a stack of active functions is expensive,
5099 and the inliner knows to instantiate any functions it might
5100 need. Therefore, we always try to defer instantiation. */
5101 {
5106 }
5109 }
5111 bool
5113 {
5115 }
5117 tree
5119 {
5121 }
5123 tree
5125 {
5126 tree fn;
5134 }