| blob | 989a0303babc785c3e9748124b797502a7701704 |
1 /* Process declarations and variables for C++ compiler.
2 Copyright (C) 1988-2015 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. */
76 /* This structure contains information about the initializations
77 and/or destructions required for a particular priority level. */
79 /* Nonzero if there have been any initializations at this priority
80 throughout the translation unit. */
82 /* Nonzero if there have been any destructions at this priority
83 throughout the translation unit. */
108 /* A list of static class variables. This is needed, because a
109 static class variable can be declared inside the class without
110 an initializer, and then initialized, statically, outside the class. */
113 /* A list of functions which were declared inline, but which we
114 may need to emit outline anyway. */
117 /* A list of decls that use types with no linkage, which we need to make
118 sure are defined. */
121 /* Nonzero if we're done parsing and into end-of-file activities. */
124 \f
126 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a
127 FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers
128 that apply to the function). */
130 tree
132 cp_ref_qualifier rqual)
133 {
134 tree raises;
135 tree attrs;
164 }
166 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its
167 return type changed to NEW_RET. */
169 tree
171 {
172 tree newtype;
185 {
190 }
191 else
192 newtype = build_method_type_directly
202 }
204 /* Build a PARM_DECL with NAME and TYPE, and set DECL_ARG_TYPE
205 appropriately. */
207 tree
209 {
212 /* DECL_ARG_TYPE is only used by the back end and the back end never
213 sees templates. */
218 }
220 /* Returns a PARM_DECL for a parameter of the indicated TYPE, with the
221 indicated NAME. */
223 tree
225 {
228 /* All our artificial parms are implicitly `const'; they cannot be
229 assigned to. */
232 }
234 /* Constructors for types with virtual baseclasses need an "in-charge" flag
235 saying whether this constructor is responsible for initialization of
236 virtual baseclasses or not. All destructors also need this "in-charge"
237 flag, which additionally determines whether or not the destructor should
238 free the memory for the object.
240 This function adds the "in-charge" flag to member function FN if
241 appropriate. It is called from grokclassfn and tsubst.
242 FN must be either a constructor or destructor.
244 The in-charge flag follows the 'this' parameter, and is followed by the
245 VTT parm (if any), then the user-written parms. */
247 void
249 {
252 /* If we've already add the in-charge parameter don't do it again. */
256 /* When processing templates we can't know, in general, whether or
257 not we're going to have virtual baseclasses. */
261 /* We don't need an in-charge parameter for constructors that don't
262 have virtual bases. */
273 /* If this is a subobject constructor or destructor, our caller will
274 pass us a pointer to our VTT. */
276 {
279 /* First add it to DECL_ARGUMENTS between 'this' and the real args... */
283 /* ...and then to TYPE_ARG_TYPES. */
287 }
289 /* Then add the in-charge parm (before the VTT parm). */
295 /* Insert our new parameter(s) into the list. */
298 /* And rebuild the function type. */
300 arg_types);
305 fntype = (cp_build_type_attribute_variant
309 /* Now we've got the in-charge parameter. */
311 }
313 /* Classes overload their constituent function names automatically.
314 When a function name is declared in a record structure,
315 its name is changed to it overloaded name. Since names for
316 constructors and destructors can conflict, we place a leading
317 '$' for destructors.
319 CNAME is the name of the class we are grokking for.
321 FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'.
323 FLAGS contains bits saying what's special about today's
324 arguments. DTOR_FLAG == DESTRUCTOR.
326 If FUNCTION is a destructor, then we must add the `auto-delete' field
327 as a second parameter. There is some hair associated with the fact
328 that we must "declare" this variable in the manner consistent with the
329 way the rest of the arguments were declared.
331 QUALS are the qualifiers for the this pointer. */
333 void
335 {
338 /* Even within an `extern "C"' block, members get C++ linkage. See
339 [dcl.link] for details. */
343 {
347 }
356 }
358 /* Create an ARRAY_REF, checking for the user doing things backwards
359 along the way. DECLTYPE_P is for N3276, as in the parser. */
361 tree
364 {
365 tree type;
366 tree expr;
374 {
381 }
387 /* If they have an `operator[]', use that. */
389 {
395 }
396 else
397 {
400 /* Otherwise, create an ARRAY_REF for a pointer or array type.
401 It is a little-known fact that, if `a' is an array and `i' is
402 an int, you can write `i[a]', which means the same thing as
403 `a[i]'. */
406 else
411 else
426 else
427 {
431 }
437 }
442 }
444 /* Given the cast expression EXP, checking out its validity. Either return
445 an error_mark_node if there was an unavoidable error, return a cast to
446 void for trying to delete a pointer w/ the value 0, or return the
447 call to delete. If DOING_VEC is true, we handle things differently
448 for doing an array delete.
449 Implements ARM $5.3.4. This is called from the parser. */
451 tree
453 tsubst_flags_t complain)
454 {
461 {
467 }
469 /* An array can't have been allocated by new, so complain. */
476 {
480 }
484 /* As of Valley Forge, you can delete a pointer to const. */
486 /* You can't delete functions. */
488 {
492 }
494 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */
496 {
499 }
501 /* Deleting a pointer with the value zero is valid and has no effect. */
507 sfk_deleting_destructor,
509 else
512 complain);
513 }
515 /* Report an error if the indicated template declaration is not the
516 sort of thing that should be a member template. */
518 void
520 {
521 tree decl;
530 {
531 /* The parser rejects template declarations in local classes
532 (with the exception of generic lambdas). */
534 /* The parser rejects any use of virtual in a function template. */
538 /* The debug-information generating code doesn't know what to do
539 with member templates. */
541 }
544 else
546 }
548 /* Return true iff TYPE is a valid Java parameter or return type. */
550 static bool
552 {
559 {
562 {
571 {
577 }
579 }
580 }
582 }
584 /* For a METHOD in a Java class CTYPE, return true if
585 the parameter and return types are valid Java types.
586 Otherwise, print appropriate error messages, and return false. */
588 bool
590 {
596 {
600 }
609 {
612 {
617 }
618 }
620 }
622 /* Sanity check: report error if this function FUNCTION is not
623 really a member of the class (CTYPE) it is supposed to belong to.
624 TEMPLATE_PARMS is used to specify the template parameters of a member
625 template passed as FUNCTION_DECL. If the member template is passed as a
626 TEMPLATE_DECL, it can be NULL since the parameters can be extracted
627 from the declaration. If the function is not a function template, it
628 must be NULL.
629 It returns the original declaration for the function, NULL_TREE if
630 no declaration was found, error_mark_node if an error was emitted. */
632 tree
634 {
637 tree pushed_scope;
643 /* Since this is a specialization of a member template,
644 we're not going to find the declaration in the class.
645 For example, in:
647 struct S { template <typename T> void f(T); };
648 template <> void S::f(int);
650 we're not going to find `S::f(int)', but there's no
651 reason we should, either. We let our callers know we didn't
652 find the method, but we don't complain. */
655 /* Basic sanity check: for a template function, the template parameters
656 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */
658 {
662 {
666 }
668 }
670 /* OK, is this a definition of a member template? */
673 /* [temp.mem]
675 A destructor shall not be a member template. */
677 {
680 }
682 /* We must enter the scope here, because conversion operators are
683 named by target type, and type equivalence relies on typenames
684 resolving within the scope of CTYPE. */
688 {
696 {
703 /* We cannot simply call decls_match because this doesn't
704 work for static member functions that are pretending to
705 be methods, and because the name may have been changed by
706 asm("new_name"). */
708 /* Get rid of the this parameter on functions that become
709 static. */
714 /* A member template definition only matches a member template
715 declaration. */
719 /* ref-qualifier or absence of same must match. */
724 /* While finding a match, same types and params are not enough
725 if the function is versioned. Also check version ("target")
726 attributes. */
731 && (!is_template
740 }
742 {
746 }
757 {
762 {
764 {
767 {
770 }
771 }
772 else
774 }
779 else
782 }
783 }
786 else
793 }
795 /* DECL is a function with vague linkage. Remember it so that at the
796 end of the translation unit we can decide whether or not to emit
797 it. */
799 void
801 {
804 }
806 /* As above, but for variable template instantiations. */
808 void
810 {
812 }
814 /* We have just processed the DECL, which is a static data member.
815 The other parameters are as for cp_finish_decl. */
817 void
820 tree asmspec_tree,
822 {
825 /* We cannot call pushdecl here, because that would fill in the
826 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do
827 the right thing, namely, to put this decl out straight away. */
833 /* We already complained about the template definition. */
837 else
841 {
847 }
856 }
858 /* DECLARATOR and DECLSPECS correspond to a class member. The other
859 parameters are as for cp_finish_decl. Return the DECL for the
860 class member declared. */
862 tree
866 tree asmspec_tree,
867 tree attrlist)
868 {
869 tree value;
872 tree name;
882 /* friend or constructor went bad. */
888 {
891 }
893 /* Pass friendly classes back. */
901 {
903 {
906 }
911 value);
912 }
914 /* Stash away type declarations. */
916 {
921 {
924 /* If this is a typedef that names the class for linkage purposes
925 (7.1.3p8), apply any attributes directly to the type. */
931 }
938 /* It's important that push_template_decl below follows
939 set_underlying_type above so that the created template
940 carries the properly set type of VALUE. */
946 }
951 {
954 }
960 {
962 {
964 {
968 }
970 {
972 {
976 }
977 }
981 {
986 else
988 value);
989 }
990 else
991 {
995 value);
996 else
998 value);
999 }
1000 }
1005 }
1007 /* Pass friend decls back. */
1013 /* Need to set this before push_template_decl. */
1018 {
1022 }
1029 else
1033 {
1058 /* Pass friends back this way. */
1067 }
1069 }
1071 /* Like `grokfield', but for bitfields.
1072 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */
1074 tree
1077 tree attrlist)
1078 {
1086 /* Pass friendly classes back. */
1093 {
1096 }
1099 {
1102 }
1104 /* Usually, finish_struct_1 catches bitfields with invalid types.
1105 But, in the case of bitfields with function type, we confuse
1106 ourselves into thinking they are member functions, so we must
1107 check here. */
1109 {
1113 }
1116 {
1120 }
1123 {
1126 }
1130 {
1131 /* The width must be an integer type. */
1138 }
1146 }
1148 \f
1149 /* Returns true iff ATTR is an attribute which needs to be applied at
1150 instantiation time rather than template definition time. */
1152 static bool
1154 {
1158 tree arg;
1161 /* Unknown attribute. */
1164 /* Attribute weak handling wants to write out assembly right away. */
1168 /* Attribute unused is applied directly, as it appertains to
1169 decls. */
1173 /* #pragma omp declare simd attribute needs to be always deferred. */
1178 /* If any of the arguments are dependent expressions, we can't evaluate
1179 the attribute until instantiation time. */
1181 {
1184 /* If the first attribute argument is an identifier, only consider
1185 second and following arguments. Attributes like mode, format,
1186 cleanup and several target specific attributes aren't late
1187 just because they have an IDENTIFIER_NODE as first argument. */
1194 }
1199 {
1202 /* We can't apply any attributes to a completely unknown type until
1203 instantiation time. */
1209 /* Also defer most attributes on dependent types. This is not
1210 necessary in all cases, but is the better default. */
1212 /* But some attributes specifically apply to templates. */
1217 else
1219 }
1220 else
1222 }
1224 /* ATTR_P is a list of attributes. Remove any attributes which need to be
1225 applied at instantiation time and return them. If IS_DEPENDENT is true,
1226 the declaration itself is dependent, so all attributes should be applied
1227 at instantiation time. */
1229 static tree
1231 {
1240 {
1242 {
1248 }
1249 else
1251 }
1254 }
1256 /* Remove any late attributes from the list in ATTR_P and attach them to
1257 DECL_P. */
1259 static void
1261 {
1273 else
1278 /* Merge the late attributes at the beginning with the attribute
1279 list. */
1284 {
1285 /* We've added new attributes directly to the main variant, so
1286 now we need to update all of the other variants to include
1287 these new attributes. */
1288 tree variant;
1291 {
1294 }
1295 }
1296 }
1298 /* Return true iff ATTRS are acceptable attributes to be applied in-place
1299 to a typedef which gives a previously anonymous class or enum a name for
1300 linkage purposes. */
1302 bool
1304 {
1306 {
1310 }
1312 }
1314 /* Like reconstruct_complex_type, but handle also template trees. */
1316 tree
1318 {
1323 {
1327 }
1329 {
1333 }
1335 {
1338 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the
1339 element type qualification will be handled by the recursive
1340 cp_reconstruct_complex_type call and cp_build_qualified_type
1341 for ARRAY_TYPEs changes the element type. */
1343 }
1345 {
1352 }
1354 {
1357 /* The build_method_type_directly() routine prepends 'this' to argument list,
1358 so we must compensate by getting rid of it. */
1359 outer
1360 = build_method_type_directly
1363 }
1365 {
1368 }
1369 else
1380 }
1382 /* Replaces any constexpr expression that may be into the attributes
1383 arguments with their reduced value. */
1385 static void
1387 {
1391 tree attr;
1393 {
1394 tree arg;
1396 {
1400 }
1401 }
1402 }
1404 /* Return true if TYPE is an OpenMP mappable type. */
1405 bool
1407 {
1408 /* Mappable type has to be complete. */
1411 /* Arrays have mappable type if the elements have mappable type. */
1414 /* A mappable type cannot contain virtual members. */
1417 /* All data members must be non-static. */
1419 {
1420 tree field;
1424 /* All fields must have mappable types. */
1428 }
1430 }
1432 /* Like decl_attributes, but handle C++ complexity. */
1434 void
1436 {
1441 /* Add implicit "omp declare target" attribute if requested. */
1446 {
1461 else
1464 }
1467 {
1472 }
1480 {
1481 attributes
1485 }
1486 else
1492 /* Propagate deprecation out to the template. */
1495 {
1501 }
1502 }
1503 \f
1504 /* Walks through the namespace- or function-scope anonymous union
1505 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1506 Returns one of the fields for use in the mangled name. */
1508 static tree
1510 {
1512 tree field;
1514 /* Rather than write the code to handle the non-union case,
1515 just give an error. */
1517 {
1520 }
1525 {
1526 tree decl;
1527 tree ref;
1532 {
1536 }
1546 else
1551 {
1552 tree base;
1568 }
1571 else
1576 }
1579 }
1581 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1582 anonymous union, then all members must be laid out together. PUBLIC_P
1583 is nonzero if this union is not declared static. */
1585 void
1587 {
1588 tree type;
1589 tree main_decl;
1598 /* The VAR_DECL's context is the same as the TYPE's context. */
1605 {
1608 }
1614 {
1617 }
1620 {
1621 /* Use main_decl to set the mangled name. */
1627 }
1631 }
1632 \f
1633 /* Auxiliary functions to make type signatures for
1634 `operator new' and `operator delete' correspond to
1635 what compiler will be expecting. */
1637 tree
1639 {
1646 {
1649 }
1652 {
1654 {
1655 /* [basic.stc.dynamic.allocation]
1657 The first parameter shall not have an associated default
1658 argument. */
1661 /* Throw away the default argument. */
1663 }
1666 {
1669 }
1670 }
1671 else
1679 {
1682 /* Fall through. */
1684 type = build_exception_variant
1687 /* Fall through. */
1689 }
1691 }
1693 tree
1695 {
1702 {
1705 }
1709 {
1714 ptr_type_node);
1715 }
1717 {
1720 /* Fall through. */
1722 type = build_exception_variant
1725 /* Fall through. */
1727 }
1730 }
1731 \f
1732 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1733 and mark them as needed. */
1735 static void
1737 {
1738 tree fnaddr;
1743 {
1744 tree fn;
1750 /* This entry is an offset: a virtual base class offset, a
1751 virtual call offset, an RTTI offset, etc. */
1756 /* When we don't have vcall offsets, we output thunks whenever
1757 we output the vtables that contain them. With vcall offsets,
1758 we know all the thunks we'll need when we emit a virtual
1759 function, so we emit the thunks there instead. */
1763 }
1764 }
1766 /* Set DECL up to have the closest approximation of "initialized common"
1767 linkage available. */
1769 void
1771 {
1776 /* We can just emit function and compiler-generated variables
1777 statically; having multiple copies is (for the most part) only
1778 a waste of space.
1780 There are two correctness issues, however: the address of a
1781 template instantiation with external linkage should be the
1782 same, independent of what translation unit asks for the
1783 address, and this will not hold when we emit multiple copies of
1784 the function. However, there's little else we can do.
1786 Also, by default, the typeinfo implementation assumes that
1787 there will be only one copy of the string used as the name for
1788 each type. Therefore, if weak symbols are unavailable, the
1789 run-time library should perform a more conservative check; it
1790 should perform a string comparison, rather than an address
1791 comparison. */
1793 else
1794 {
1795 /* Static data member template instantiations, however, cannot
1796 have multiple copies. */
1801 {
1804 }
1806 {
1807 /* We can't do anything useful; leave vars for explicit
1808 instantiation. */
1811 }
1812 }
1815 }
1817 /* For win32 we also want to put explicit instantiations in
1818 linkonce sections, so that they will be merged with implicit
1819 instantiations; otherwise we get duplicate symbol errors.
1820 For Darwin we do not want explicit instantiations to be
1821 linkonce. */
1823 void
1825 {
1826 /* We used to say that this was not necessary on targets that support weak
1827 symbols, because the implicit instantiations will defer to the explicit
1828 one. However, that's not actually the case in SVR4; a strong definition
1829 after a weak one is an error. Also, not making explicit
1830 instantiations one_only means that we can end up with two copies of
1831 some template instantiations. */
1835 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1836 we can get away with not emitting them if they aren't used. We need
1837 to for variables so that cp_finish_decl will update their linkage,
1838 because their DECL_INITIAL may not have been set properly yet. */
1843 {
1847 {
1850 /* Mark it needed so we don't forget to emit it. */
1853 }
1854 }
1855 }
1857 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1858 This predicate will give the right answer during parsing of the
1859 function, which other tests may not. */
1861 bool
1863 {
1864 /* Unfortunately, import_export_decl has not always been called
1865 before the function is processed, so we cannot simply check
1866 DECL_COMDAT. */
1875 /* A local static in an inline effectively has vague linkage. */
1878 else
1880 }
1882 /* Determine whether or not we want to specifically import or export CTYPE,
1883 using various heuristics. */
1885 static void
1887 {
1888 /* -1 for imported, 1 for exported. */
1891 /* It only makes sense to call this function at EOF. The reason is
1892 that this function looks at whether or not the first non-inline
1893 non-abstract virtual member function has been defined in this
1894 translation unit. But, we can't possibly know that until we've
1895 seen the entire translation unit. */
1901 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1902 we will have CLASSTYPE_INTERFACE_ONLY set but not
1903 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1904 heuristic because someone will supply a #pragma implementation
1905 elsewhere, and deducing it here would produce a conflict. */
1915 /* For a template class, without -fimplicit-templates, check the
1916 repository. If the virtual table is assigned to this
1917 translation unit, then export the class; otherwise, import
1918 it. */
1921 {
1922 /* The ABI specifies that the virtual table and associated
1923 information are emitted with the key method, if any. */
1925 /* If weak symbol support is not available, then we must be
1926 careful not to emit the vtable when the key function is
1927 inline. An inline function can be defined in multiple
1928 translation units. If we were to emit the vtable in each
1929 translation unit containing a definition, we would get
1930 multiple definition errors at link-time. */
1933 }
1935 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1936 a definition anywhere else. */
1940 /* Allow back ends the chance to overrule the decision. */
1945 {
1948 }
1949 }
1951 /* Return true if VAR has already been provided to the back end; in that
1952 case VAR should not be modified further by the front end. */
1953 static bool
1955 {
1957 }
1959 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1960 must be emitted in this translation unit. Mark it as such. */
1962 void
1964 {
1967 {
1968 /* Extern inline functions don't become needed when referenced.
1969 If we know a method will be emitted in other TU and no new
1970 functions can be marked reachable, just use the external
1971 definition. */
1975 /* #pragma interface and -frepo code can call mark_needed for
1976 maybe-in-charge 'tors; mark the clones as well. */
1977 tree clone;
1980 }
1982 {
1984 /* C++ frontend use mark_decl_references to force COMDAT variables
1985 to be output that might appear dead otherwise. */
1987 }
1988 }
1990 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
1991 returns true if a definition of this entity should be provided in
1992 this object file. Callers use this function to determine whether
1993 or not to let the back end know that a definition of DECL is
1994 available in this translation unit. */
1996 bool
1998 {
2000 /* This function should only be called at the end of the translation
2001 unit. We cannot be sure of whether or not something will be
2002 COMDAT until that point. */
2005 /* All entities with external linkage that are not COMDAT/EXTERN should be
2006 emitted; they may be referred to from other object files. */
2009 /* Functions marked "dllexport" must be emitted so that they are
2010 visible to other DLLs. */
2015 /* When not optimizing, do not bother to produce definitions for extern
2016 symbols. */
2025 /* If this entity was used, let the back end see it; it will decide
2026 whether or not to emit it into the object file. */
2029 /* Virtual functions might be needed for devirtualization. */
2034 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
2035 reference to DECL might cause it to be emitted later. */
2037 }
2039 /* If necessary, write out the vtables for the dynamic class CTYPE.
2040 Returns true if any vtables were emitted. */
2042 static bool
2044 {
2045 tree vtbl;
2046 tree primary_vtbl;
2050 /* If the vtables for this class have already been emitted there is
2051 nothing more to do. */
2055 /* Ignore dummy vtables made by get_vtable_decl. */
2059 /* On some targets, we cannot determine the key method until the end
2060 of the translation unit -- which is when this function is
2061 called. */
2065 /* See if any of the vtables are needed. */
2067 {
2071 }
2073 {
2074 /* If the references to this class' vtables are optimized away,
2075 still emit the appropriate debugging information. See
2076 dfs_debug_mark. */
2081 }
2083 /* The ABI requires that we emit all of the vtables if we emit any
2084 of them. */
2086 {
2087 /* Mark entities references from the virtual table as used. */
2091 {
2094 LOOKUP_NORMAL);
2096 /* It had better be all done at compile-time. */
2098 }
2100 /* Write it out. */
2104 /* Because we're only doing syntax-checking, we'll never end up
2105 actually marking the variable as written. */
2109 {
2114 }
2115 }
2117 /* Since we're writing out the vtable here, also write the debug
2118 info. */
2122 }
2124 /* A special return value from type_visibility meaning internal
2125 linkage. */
2129 /* walk_tree helper function for type_visibility. */
2131 static tree
2133 {
2136 {
2138 }
2141 {
2144 }
2149 }
2151 /* Returns the visibility of TYPE, which is the minimum visibility of its
2152 component types. */
2154 static int
2156 {
2160 }
2162 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2163 specified (or if VISIBILITY is static). If TMPL is true, this
2164 constraint is for a template argument, and takes precedence
2165 over explicitly-specified visibility on the template. */
2167 static void
2169 {
2171 {
2172 /* extern "C" declarations aren't affected by the anonymous
2173 namespace. */
2175 {
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 {
2220 else
2221 {
2229 {
2232 else
2234 }
2235 }
2238 }
2239 }
2241 /* Like c_determine_visibility, but with additional C++-specific
2242 behavior.
2244 Function-scope entities can rely on the function's visibility because
2245 it is set in start_preparsed_function.
2247 Class-scope entities cannot rely on the class's visibility until the end
2248 of the enclosing class definition.
2250 Note that because namespaces have multiple independent definitions,
2251 namespace visibility is handled elsewhere using the #pragma visibility
2252 machinery rather than by decorating the namespace declaration.
2254 The goal is for constraints from the type to give a diagnostic, and
2255 other constraints to be applied silently. */
2257 void
2259 {
2265 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2267 /* Only relevant for names with external linkage. */
2271 /* Cloned constructors and destructors get the same visibility as
2272 the underlying function. That should be set up in
2273 maybe_clone_body. */
2280 {
2285 else
2287 }
2290 else
2293 /* If DECL is a member of a class, visibility specifiers on the
2294 class can influence the visibility of the DECL. */
2297 else
2298 {
2299 /* Not a class member. */
2301 /* Virtual tables have DECL_CONTEXT set to their associated class,
2302 so they are automatically handled above. */
2307 {
2308 /* Local statics and classes get the visibility of their
2309 containing function by default, except that
2310 -fvisibility-inlines-hidden doesn't affect them. */
2313 {
2317 }
2318 else
2319 {
2323 {
2327 }
2328 else
2329 {
2333 }
2334 }
2336 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2337 but have no TEMPLATE_INFO, so don't try to check it. */
2339 }
2342 {
2343 /* Under -fvisibility-ms-compat, types are visible by default,
2344 even though their contents aren't. */
2351 else
2353 }
2355 {
2356 /* tinfo visibility is based on the type it's for. */
2357 constrain_visibility
2360 /* Give the target a chance to override the visibility associated
2361 with DECL. */
2367 }
2369 /* Template instantiations and specializations get visibility based
2372 {
2375 else
2376 {
2377 /* Set default visibility to whatever the user supplied with
2378 #pragma GCC visibility or a namespace visibility attribute. */
2381 }
2382 }
2383 }
2386 {
2387 /* If the specialization doesn't specify visibility, use the
2388 visibility from the template. */
2398 {
2402 {
2406 else
2407 {
2411 }
2412 }
2415 /* Template argument visibility outweighs #pragma or namespace
2416 visibility, but not an explicit attribute. */
2418 {
2421 {
2422 /* A class template member with explicit visibility
2423 overrides the class visibility, so we need to apply
2424 all the levels of template args directly. */
2427 {
2430 }
2431 }
2433 /* Limit visibility based on its template arguments. */
2435 }
2436 }
2437 }
2443 /* Names in an anonymous namespace get internal linkage.
2444 This might change once we implement export. */
2447 {
2448 /* Propagate anonymity from type to decl. */
2453 }
2455 /* DR 757: A type without linkage shall not be used as the type of a
2456 variable or function with linkage, unless
2457 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2458 o the variable or function is not used (3.2 [basic.def.odr]) or is
2459 defined in the same translation unit.
2461 Since non-extern "C" decls need to be defined in the same
2462 translation unit, we can make the type internal. */
2465 /* If visibility changed and DECL already has DECL_RTL, ensure
2466 symbol flags are updated. */
2473 }
2475 /* By default, static data members and function members receive
2476 the visibility of their containing class. */
2478 static void
2480 {
2486 else
2487 {
2488 /* Default to the class visibility. */
2492 }
2494 /* Give the target a chance to override the visibility associated
2495 with DECL. */
2499 /* Construction virtual tables are not exported because
2500 they cannot be referred to from other object files;
2501 their name is not standardized by the ABI. */
2507 }
2509 /* Returns true iff DECL is an inline that should get hidden visibility
2510 because of -fvisibility-inlines-hidden. */
2512 static bool
2514 {
2516 /* Don't do this for inline templates; specializations might not be
2517 inline, and we don't want them to inherit the hidden
2518 visibility. We'll set it here for all inline instantiations. */
2519 && !processing_template_decl
2524 }
2526 /* Constrain the visibility of a class TYPE based on the visibility of its
2527 field types. Warn if any fields require lesser visibility. */
2529 void
2531 {
2532 tree binfo;
2533 tree t;
2542 /* Don't warn about visibility if the class has explicit visibility. */
2548 {
2553 {
2558 }
2565 }
2569 {
2573 {
2578 }
2584 }
2585 }
2587 /* Functions for adjusting the visibility of a tagged type and its nested
2588 types and declarations when it gets a name for linkage purposes from a
2589 typedef. */
2594 /* First reset the visibility of all the types. */
2596 static void
2598 {
2603 }
2604 static void
2606 {
2608 }
2610 /* Then reset the visibility of any static data members or member
2611 functions that use those types. */
2613 static void
2615 {
2624 }
2625 static void
2627 {
2629 {
2631 {
2636 }
2638 {
2644 }
2652 }
2653 }
2654 static void
2656 {
2658 }
2659 void
2661 {
2664 }
2666 /* Set up our initial idea of what the linkage of DECL should be. */
2668 void
2670 {
2672 /* We've already made a decision as to how this function will
2675 {
2678 {
2682 /* A non-template inline function with external linkage will
2683 always be COMDAT. As we must eventually determine the
2684 linkage of all functions, and as that causes writes to
2685 the data mapped in from the PCH file, it's advantageous
2686 to mark the functions at this point. */
2690 {
2691 /* This function must have external linkage, as
2692 otherwise DECL_INTERFACE_KNOWN would have been
2693 set. */
2697 }
2698 }
2701 }
2702 }
2704 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2705 for DECL has not already been determined, do so now by setting
2706 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2707 function is called entities with vague linkage whose definitions
2708 are available must have TREE_PUBLIC set.
2710 If this function decides to place DECL in COMDAT, it will set
2711 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2712 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2713 callers defer that decision until it is clear that DECL is actually
2714 required. */
2716 void
2718 {
2727 /* We cannot determine what linkage to give to an entity with vague
2728 linkage until the end of the file. For example, a virtual table
2729 for a class will be defined if and only if the key method is
2730 defined in this translation unit. As a further example, consider
2731 that when compiling a translation unit that uses PCH file with
2732 "-frepo" it would be incorrect to make decisions about what
2733 entities to emit when building the PCH; those decisions must be
2734 delayed until the repository information has been processed. */
2736 /* Object file linkage for explicit instantiations is handled in
2737 mark_decl_instantiated. For static variables in functions with
2738 vague linkage, maybe_commonize_var is used.
2740 Therefore, the only declarations that should be provided to this
2741 function are those with external linkage that are:
2743 * implicit instantiations of function templates
2745 * inline function
2747 * implicit instantiations of static data members of class
2748 templates
2750 * virtual tables
2752 * typeinfo objects
2754 Furthermore, all entities that reach this point must have a
2755 definition available in this translation unit.
2757 The following assertions check these conditions. */
2759 /* Any code that creates entities with TREE_PUBLIC cleared should
2760 also set DECL_INTERFACE_KNOWN. */
2766 else
2770 /* Check that a definition of DECL is available in this translation
2771 unit. */
2774 /* Assume that DECL will not have COMDAT linkage. */
2776 /* Assume that DECL will not be imported into this translation
2777 unit. */
2780 /* See if the repository tells us whether or not to emit DECL in
2781 this translation unit. */
2786 {
2787 /* The repository indicates that this entity should be defined
2788 here. Make sure the back end honors that request. */
2790 /* Output the definition as an ordinary strong definition. */
2794 }
2797 /* We have already decided what to do with this DECL; there is no
2798 need to check anything further. */
2799 ;
2801 {
2813 /* The ABI requires that all virtual tables be emitted with
2814 COMDAT linkage. However, on systems where COMDAT symbols
2815 don't show up in the table of contents for a static
2816 archive, or on systems without weak symbols (where we
2817 approximate COMDAT linkage by using internal linkage), the
2818 linker will report errors about undefined symbols because
2819 it will not see the virtual table definition. Therefore,
2820 in the case that we know that the virtual table will be
2821 emitted in only one translation unit, we make the virtual
2822 table an ordinary definition with external linkage. */
2825 {
2826 /* CLASS_TYPE is being exported from this translation unit,
2827 so DECL should be defined here. */
2829 /* If a class is declared in a header with the "extern
2830 template" extension, then it will not be instantiated,
2831 even in translation units that would normally require
2832 it. Often such classes are explicitly instantiated in
2833 one translation unit. Therefore, the explicit
2834 instantiation must be made visible to other translation
2835 units. */
2837 else
2838 {
2839 /* The generic C++ ABI says that class data is always
2840 COMDAT, even if there is a key function. Some
2841 variants (e.g., the ARM EABI) says that class data
2842 only has COMDAT linkage if the class data might be
2843 emitted in more than one translation unit. When the
2844 key method can be inline and is inline, we still have
2845 to arrange for comdat even though
2846 class_data_always_comdat is false. */
2850 {
2851 /* The ABI requires COMDAT linkage. Normally, we
2852 only emit COMDAT things when they are needed;
2853 make sure that we realize that this entity is
2854 indeed needed. */
2857 }
2858 }
2859 }
2863 else
2865 }
2867 {
2870 {
2876 /* If -fno-rtti was specified, then we cannot be sure
2877 that RTTI information will be emitted with the
2878 virtual table of the class, so we must emit it
2879 wherever it is used. */
2882 else
2883 {
2886 {
2892 {
2895 }
2896 }
2897 else
2899 }
2900 }
2901 else
2903 }
2905 {
2906 /* DECL is an implicit instantiation of a function or static
2907 data member. */
2910 || (flag_implicit_inline_templates
2914 else
2915 /* If we are not implicitly generating templates, then mark
2916 this entity as undefined in this translation unit. */
2918 }
2920 {
2922 {
2926 {
2930 && ! flag_implement_inlines
2936 /* Always make artificials weak. */
2939 else
2941 }
2942 }
2943 else
2945 }
2946 else
2950 {
2951 /* If we are importing DECL into this translation unit, mark is
2952 an undefined here. */
2955 }
2957 {
2958 /* If we decided to put DECL in COMDAT, mark it accordingly at
2959 this point. */
2961 }
2964 }
2966 /* Return an expression that performs the destruction of DECL, which
2967 must be a VAR_DECL whose type has a non-trivial destructor, or is
2968 an array whose (innermost) elements have a non-trivial destructor. */
2970 tree
2972 {
2976 }
2978 /* Returns the initialization guard variable for the variable DECL,
2979 which has static storage duration. */
2981 tree
2983 {
2984 tree sname;
2985 tree guard;
2990 {
2991 tree guard_type;
2993 /* We use a type that is big enough to contain a mutex as well
2994 as an integer counter. */
2999 /* The guard should have the same linkage as what it guards. */
3016 }
3018 }
3020 /* Return those bits of the GUARD variable that should be set when the
3021 guarded entity is actually initialized. */
3023 static tree
3025 {
3027 {
3028 /* We only set the first byte of the guard, in order to leave room
3029 for a mutex in the high-order bits. */
3032 guard);
3035 guard);
3037 }
3040 }
3042 /* Return an expression which determines whether or not the GUARD
3043 variable has already been initialized. */
3045 tree
3047 {
3048 tree guard_value;
3050 /* Check to see if the GUARD is zero. */
3053 /* Mask off all but the low bit. */
3055 {
3061 tf_warning_or_error);
3062 }
3069 tf_warning_or_error);
3070 }
3072 /* Return an expression which sets the GUARD variable, indicating that
3073 the variable being guarded has been initialized. */
3075 tree
3077 {
3078 tree guard_init;
3080 /* Set the GUARD to one. */
3086 tf_warning_or_error);
3087 }
3089 /* Returns true iff we can tell that VAR does not have a dynamic
3090 initializer. */
3092 static bool
3094 {
3095 /* If it's defined in another TU, we can't tell. */
3098 /* If it has a non-trivial destructor, registering the destructor
3099 counts as dynamic initialization. */
3102 /* If it's in this TU, its initializer has been processed, unless
3103 it's a case of self-initialization, then DECL_INITIALIZED_P is
3104 false while the initializer is handled by finish_id_expression. */
3107 /* If it has no initializer or a constant one, it's not dynamic. */
3110 }
3112 /* Returns true iff VAR is a variable that needs uses to be
3113 wrapped for possible dynamic initialization. */
3115 static bool
3117 {
3123 }
3125 /* Get the FUNCTION_DECL for the shared TLS init function for this
3126 translation unit. */
3128 static tree
3130 {
3134 {
3137 void_list_node));
3143 }
3145 }
3147 /* Get a FUNCTION_DECL for the init function for the thread_local
3148 variable VAR. The init function will be an alias to the function
3149 that initializes all the non-local TLS variables in the translation
3150 unit. The init function is only used by the wrapper function. */
3152 static tree
3154 {
3155 /* Only C++11 TLS vars need this init fn. */
3159 /* If -fno-extern-tls-init, assume that we don't need to call
3160 a tls init function for a variable defined in another TU. */
3164 #ifdef ASM_OUTPUT_DEF
3165 /* If the variable is internal, or if we can't generate aliases,
3166 call the local init function directly. */
3168 #endif
3174 {
3177 void_list_node));
3186 {
3188 /* If the variable is defined somewhere else and might have static
3189 initialization, make the init function a weak reference. */
3195 else
3197 }
3207 }
3209 }
3211 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3212 variable VAR. The wrapper function calls the init function (if any) for
3213 VAR and then returns a reference to VAR. The wrapper function is used
3214 in place of VAR everywhere VAR is mentioned. */
3216 tree
3218 {
3219 /* Only C++11 TLS vars need this wrapper fn. */
3226 {
3227 /* A named rvalue reference is an lvalue, so the wrapper should
3228 always return an lvalue reference. */
3237 /* The wrapper is inline and emitted everywhere var is used. */
3240 {
3242 #ifdef HAVE_GAS_HIDDEN
3243 /* Make the wrapper bind locally; there's no reason to share
3244 the wrapper between multiple shared objects. */
3247 #endif
3248 }
3254 #if 0
3255 /* We want CSE to commonize calls to the wrapper, but marking it as
3256 pure is unsafe since it has side-effects. I guess we need a new
3257 ECF flag even weaker than ECF_PURE. FIXME! */
3259 #endif
3264 }
3266 }
3268 /* At EOF, generate the definition for the TLS wrapper function FN:
3270 T& var_wrapper() {
3271 if (init_fn) init_fn();
3272 return var;
3273 } */
3275 static void
3277 {
3282 /* Only call the init fn if there might be one. */
3284 {
3286 /* If init_fn is a weakref, make sure it exists before calling. */
3288 {
3293 tf_warning_or_error);
3295 }
3299 {
3302 }
3303 }
3304 else
3305 /* If there's no initialization, the wrapper is a constant function. */
3310 }
3312 /* Start the process of running a particular set of global constructors
3313 or destructors. Subroutine of do_[cd]tors. Also called from
3314 vtv_start_verification_constructor_init_function. */
3316 static tree
3318 {
3319 tree body;
3320 tree fndecl;
3323 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3326 {
3329 #ifdef JOINER
3331 #else
3333 #endif
3336 }
3337 else
3343 NULL_TREE));
3348 /* Mark as artificial because it's not explicitly in the user's
3349 source code. */
3352 /* Mark this declaration as used to avoid spurious warnings. */
3355 /* Mark this function as a global constructor or destructor. */
3358 else
3364 }
3366 /* Finish the process of running a particular set of global constructors
3367 or destructors. Subroutine of do_[cd]tors. */
3369 static void
3371 {
3372 tree fn;
3374 /* Finish up. */
3379 {
3382 }
3383 else
3384 {
3387 }
3390 }
3392 /* The names of the parameters to the function created to handle
3393 initializations and destructions for objects with static storage
3394 duration. */
3398 /* The name of the function we create to handle initializations and
3399 destructions for objects with static storage duration. */
3402 /* The declaration for the __INITIALIZE_P argument. */
3405 /* The declaration for the __PRIORITY argument. */
3408 /* The declaration for the static storage duration function. */
3411 /* All the static storage duration functions created in this
3412 translation unit. */
3415 /* A map from priority levels to information about that priority
3416 level. There may be many such levels, so efficient lookup is
3417 important. */
3420 /* Begins the generation of the function that will handle all
3421 initialization and destruction of objects with static storage
3422 duration. The function generated takes two parameters of type
3423 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3424 nonzero, it performs initializations. Otherwise, it performs
3425 destructions. It only performs those initializations or
3426 destructions with the indicated __PRIORITY. The generated function
3427 returns no value.
3429 It is assumed that this function will only be called once per
3430 translation unit. */
3432 static tree
3434 {
3435 tree type;
3436 tree body;
3439 /* Create the identifier for this function. It will be of the form
3440 SSDF_IDENTIFIER_<number>. */
3445 NULL_TREE);
3447 /* Create the FUNCTION_DECL itself. */
3450 type);
3454 /* Put this function in the list of functions to be called from the
3455 static constructors and destructors. */
3457 {
3460 /* Take this opportunity to initialize the map from priority
3461 numbers to information about that priority level. */
3464 /*delete_value_fn=*/
3467 /* We always need to generate functions for the
3468 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3469 priorities later, we'll be sure to find the
3470 DEFAULT_INIT_PRIORITY. */
3472 }
3476 /* Create the argument list. */
3477 initialize_p_decl = cp_build_parm_decl
3481 priority_decl = cp_build_parm_decl
3489 /* Put the function in the global scope. */
3492 /* Start the function itself. This is equivalent to declaring the
3493 function as:
3495 static void __ssdf (int __initialize_p, init __priority_p);
3497 It is static because we only need to call this function from the
3498 various constructor and destructor functions for this module. */
3501 SF_PRE_PARSED);
3503 /* Set up the scope of the outermost block in the function. */
3507 }
3509 /* Finish the generation of the function which performs initialization
3510 and destruction of objects with static storage duration. After
3511 this point, no more such objects can be created. */
3513 static void
3515 {
3516 /* Close out the function. */
3519 }
3521 /* Return the information about the indicated PRIORITY level. If no
3522 code to handle this level has yet been generated, generate the
3523 appropriate prologue. */
3525 static priority_info
3527 {
3528 priority_info pi;
3529 splay_tree_node n;
3534 {
3535 /* Create a new priority information structure, and insert it
3536 into the map. */
3543 }
3544 else
3548 }
3550 /* The effective initialization priority of a DECL. */
3552 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3553 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3554 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3556 /* Whether a DECL needs a guard to protect it against multiple
3557 initialization. */
3559 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3560 || DECL_ONE_ONLY (decl) \
3561 || DECL_WEAK (decl)))
3563 /* Called from one_static_initialization_or_destruction(),
3564 via walk_tree.
3565 Walks the initializer list of a global variable and looks for
3566 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3567 and that have their DECL_CONTEXT() == NULL.
3568 For each such temporary variable, set their DECL_CONTEXT() to
3569 the current function. This is necessary because otherwise
3570 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3571 when trying to refer to a temporary variable that does not have
3572 it's DECL_CONTECT() properly set. */
3573 static tree
3577 {
3581 {
3582 tree var;
3590 }
3593 }
3595 /* Set up to handle the initialization or destruction of DECL. If
3596 INITP is nonzero, we are initializing the variable. Otherwise, we
3597 are destroying it. */
3599 static void
3601 {
3603 tree guard;
3605 /* If we are supposed to destruct and there's a trivial destructor,
3606 nothing has to be done. */
3611 /* Trick the compiler into thinking we are at the file and line
3612 where DECL was declared so that error-messages make sense, and so
3613 that the debugger will show somewhat sensible file and line
3614 information. */
3617 /* Make sure temporary variables in the initialiser all have
3618 their DECL_CONTEXT() set to a value different from NULL_TREE.
3619 This can happen when global variables initialisers are built.
3620 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3621 the temporary variables that might have been generated in the
3622 accompagning initialisers is NULL_TREE, meaning the variables have been
3623 declared in the global namespace.
3624 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3625 of the temporaries are set to the current function decl. */
3627 fix_temporary_vars_context_r,
3628 NULL);
3630 /* Because of:
3632 [class.access.spec]
3634 Access control for implicit calls to the constructors,
3635 the conversion functions, or the destructor called to
3636 create and destroy a static data member is performed as
3637 if these calls appeared in the scope of the member's
3638 class.
3640 we pretend we are in a static member function of the class of
3641 which the DECL is a member. */
3643 {
3646 }
3648 /* Assume we don't need a guard. */
3650 /* We need a guard if this is an object with external linkage that
3651 might be initialized in more than one place. (For example, a
3652 static data member of a template, when the data member requires
3653 construction.) */
3655 {
3656 tree guard_cond;
3660 /* When using __cxa_atexit, we just check the GUARD as we would
3661 for a local static. */
3663 {
3664 /* When using __cxa_atexit, we never try to destroy
3665 anything from a static destructor. */
3668 }
3669 /* If we don't have __cxa_atexit, then we will be running
3670 destructors from .fini sections, or their equivalents. So,
3671 we need to know how many times we've tried to initialize this
3672 object. We do initializations only if the GUARD is zero,
3673 i.e., if we are the first to initialize the variable. We do
3674 destructions only if the GUARD is one, i.e., if we are the
3675 last to destroy the variable. */
3677 guard_cond
3679 EQ_EXPR,
3681 guard,
3683 tf_warning_or_error),
3684 integer_one_node,
3685 tf_warning_or_error);
3686 else
3687 guard_cond
3689 EQ_EXPR,
3691 guard,
3693 tf_warning_or_error),
3694 integer_zero_node,
3695 tf_warning_or_error);
3699 }
3702 /* If we're using __cxa_atexit, we have not already set the GUARD,
3703 so we must do so now. */
3707 /* Perform the initialization or destruction. */
3709 {
3711 {
3714 {
3718 }
3719 }
3721 /* If we're using __cxa_atexit, register a function that calls the
3722 destructor for the object. */
3725 }
3726 else
3729 /* Finish the guard if-stmt, if necessary. */
3731 {
3734 }
3736 /* Now that we're done with DECL we don't need to pretend to be a
3737 member of its class any longer. */
3740 }
3742 /* Generate code to do the initialization or destruction of the decls in VARS,
3743 a TREE_LIST of VAR_DECL with static storage duration.
3744 Whether initialization or destruction is performed is specified by INITP. */
3746 static void
3748 {
3751 /* Build the outer if-stmt to check for initialization or destruction. */
3755 EQ_EXPR,
3756 initialize_p_decl,
3757 cond,
3758 tf_warning_or_error);
3761 /* To make sure dynamic construction doesn't access globals from other
3762 compilation units where they might not be yet constructed, for
3763 -fsanitize=address insert __asan_before_dynamic_init call that
3764 prevents access to either all global variables that need construction
3765 in other compilation units, or at least those that haven't been
3766 initialized yet. Variables that need dynamic construction in
3767 the current compilation unit are kept accessible. */
3774 tree priority_if_stmt;
3776 priority_info pi;
3778 /* If we don't need a destructor, there's nothing to do. Avoid
3779 creating a possibly empty if-stmt. */
3781 {
3784 }
3786 /* Remember that we had an initialization or finalization at this
3787 priority. */
3792 else
3795 /* Conditionalize this initialization on being in the right priority
3796 and being initializing/finalizing appropriately. */
3799 EQ_EXPR,
3800 priority_decl,
3802 tf_warning_or_error);
3805 /* Process initializers with same priority. */
3809 /* Do one initialization or destruction. */
3813 /* Finish up the priority if-stmt body. */
3819 /* Revert what __asan_before_dynamic_init did by calling
3820 __asan_after_dynamic_init. */
3824 /* Finish up the init/destruct if-stmt body. */
3827 }
3829 /* VARS is a list of variables with static storage duration which may
3830 need initialization and/or finalization. Remove those variables
3831 that don't really need to be initialized or finalized, and return
3832 the resulting list. The order in which the variables appear in
3833 VARS is in reverse order of the order in which they should actually
3834 be initialized. The list we return is in the unreversed order;
3835 i.e., the first variable should be initialized first. */
3837 static tree
3839 {
3844 {
3849 /* Deal gracefully with error. */
3851 {
3854 }
3856 /* The only things that can be initialized are variables. */
3859 /* If this object is not defined, we don't need to do anything
3860 here. */
3862 {
3865 }
3867 /* Also, if the initializer already contains errors, we can bail
3868 out now. */
3871 {
3874 }
3876 /* This variable is going to need initialization and/or
3877 finalization, so we add it to the list. */
3881 }
3884 }
3886 /* Make sure we have told the back end about all the variables in
3887 VARS. */
3889 static void
3891 {
3892 tree v;
3895 {
3898 {
3901 }
3902 }
3903 }
3905 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
3906 (otherwise) that will initialize all global objects with static
3907 storage duration having the indicated PRIORITY. */
3909 static void
3912 {
3914 tree fndecl;
3915 tree body;
3919 /* ??? */
3920 /* Was: locus->line++; */
3922 /* We use `I' to indicate initialization and `D' to indicate
3923 destruction. */
3926 /* We emit the function lazily, to avoid generating empty
3927 global constructors and destructors. */
3930 /* For Objective-C++, we may need to initialize metadata found in this module.
3931 This must be done _before_ any other static initializations. */
3934 {
3937 }
3939 /* Call the static storage duration function with appropriate
3940 arguments. */
3942 {
3943 /* Calls to pure or const functions will expand to nothing. */
3945 {
3946 tree call;
3953 constructor_p),
3955 priority),
3956 NULL_TREE);
3958 }
3959 }
3961 /* Close out the function. */
3964 }
3966 /* Generate constructor and destructor functions for the priority
3967 indicated by N. */
3969 static int
3971 {
3976 /* Generate the functions themselves, but only if they are really
3977 needed. */
3983 /* Keep iterating. */
3985 }
3987 /* Java requires that we be able to reference a local address for a
3988 method, and not be confused by PLT entries. If hidden aliases are
3989 supported, collect and return all the functions for which we should
3990 emit a hidden alias. */
3994 {
3998 #ifndef HAVE_GAS_HIDDEN
4000 #endif
4003 {
4009 {
4013 }
4014 }
4017 }
4020 /* Java requires that we be able to reference a local address for a
4021 method, and not be confused by PLT entries. If hidden aliases are
4022 supported, emit one for each java function that we've emitted.
4023 CANDIDATES is the set of FUNCTION_DECLs that were gathered
4024 by collect_candidates_for_java_method_aliases. */
4026 static void
4028 {
4031 #ifndef HAVE_GAS_HIDDEN
4033 #endif
4036 {
4041 {
4042 /* Mangle the name in a predictable way; we need to reference
4043 this from a java compiled object file. */
4059 }
4060 }
4061 }
4063 /* Return C++ property of T, based on given operation OP. */
4065 static int
4067 {
4069 {
4084 }
4085 }
4087 /* Collect source file references recursively, starting from NAMESPC. */
4089 static void
4091 {
4092 tree t;
4097 /* Iterate over names in this name space. */
4102 /* Dump siblings, if any */
4105 /* Dump children, if any */
4107 }
4109 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4110 starting from NAMESPC. */
4112 static void
4114 {
4118 /* Collect decls from this namespace */
4121 /* Collect siblings, if any */
4124 /* Collect children, if any */
4126 }
4128 /* Returns true iff there is a definition available for variable or
4129 function DECL. */
4131 static bool
4133 {
4136 else
4137 {
4140 }
4141 }
4143 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4145 [expr.const]
4147 An integral constant-expression can only involve ... const
4148 variables of integral or enumeration types initialized with
4149 constant expressions ...
4151 C++0x also allows constexpr variables and temporaries initialized
4152 with constant expressions. We handle the former here, but the latter
4153 are just folded away in cxx_eval_constant_expression.
4155 The standard does not require that the expression be non-volatile.
4156 G++ implements the proposed correction in DR 457. */
4158 bool
4160 {
4164 /* We don't know if a template static data member is initialized with
4165 a constant expression until we instantiate its initializer. Even
4166 in the case of a constexpr variable, we can't treat it as a
4167 constant until its initializer is complete in case it's used in
4168 its own initializer. */
4171 }
4173 /* Returns true if DECL could be a symbolic constant variable, depending on
4174 its initializer. */
4176 bool
4178 {
4186 }
4188 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4189 called from grokfndecl and grokvardecl; in all modes it is called from
4190 cp_write_global_declarations. */
4192 void
4194 {
4196 /* In C++11 it's ok if the decl is defined. */
4200 /* The type that got us on no_linkage_decls must have gotten a name for
4203 /* The type might end up having a typedef name for linkage purposes. */
4206 {
4214 /* DRs 132, 319 and 389 seem to indicate types with
4215 no linkage can only be used to declare extern "C"
4216 entities. Since it's not always an error in the
4217 ISO C++ 90 Standard, we only issue a warning. */
4219 "with no linkage used to declare variable %q#D with "
4221 else
4224 decl);
4229 }
4236 else
4239 }
4241 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4243 static void
4245 {
4247 }
4249 /* Clear DECL_EXTERNAL for NODE. */
4251 static bool
4253 {
4256 }
4258 /* Build up the function to run dynamic initializers for thread_local
4259 variables in this translation unit and alias the init functions for the
4260 individual variables to it. */
4262 static void
4264 {
4274 boolean_type_node);
4288 tf_warning_or_error);
4291 tf_warning_or_error));
4293 {
4298 #ifdef ASM_OUTPUT_DEF
4299 /* Output init aliases even with -fno-extern-tls-init. */
4301 {
4305 cgraph_node *alias
4309 }
4310 #endif
4311 }
4317 }
4319 /* The entire file is now complete. If requested, dump everything
4320 to a file. */
4322 static void
4324 {
4329 {
4332 }
4333 }
4335 /* Check the deallocation functions for CODE to see if we want to warn that
4336 only one was defined. */
4338 static void
4340 {
4346 {
4348 /* We're only interested in usual deallocation functions. */
4353 else
4355 }
4362 }
4364 /* Check the global deallocation functions to see if we want to warn about
4365 defining unsized without sized (or vice versa). */
4367 static void
4369 {
4374 }
4376 /* This routine is called at the end of compilation.
4377 Its job is to create all the code needed to initialize and
4378 destroy the global aggregates. We do the destruction
4379 first, since that way we only need to reverse the decls once. */
4381 void
4383 {
4384 tree vars;
4387 location_t locus;
4390 tree decl;
4396 /* Bad parse errors. Just forget about it. */
4401 /* This is the point to write out a PCH if we're doing that.
4402 In that case we do not want to do anything else. */
4404 {
4408 }
4412 /* Handle -fdump-ada-spec[-slim] */
4414 {
4417 else
4421 }
4423 /* FIXME - huh? was input_line -= 1;*/
4427 /* We now have to write out all the stuff we put off writing out.
4428 These include:
4430 o Template specializations that we have not yet instantiated,
4431 but which are needed.
4432 o Initialization and destruction for non-local objects with
4433 static storage duration. (Local objects with static storage
4434 duration are initialized when their scope is first entered,
4435 and are cleaned up via atexit.)
4436 o Virtual function tables.
4438 All of these may cause others to be needed. For example,
4439 instantiating one function may cause another to be needed, and
4440 generating the initializer for an object may cause templates to be
4441 instantiated, etc., etc. */
4445 do
4446 {
4447 tree t;
4448 tree decl;
4452 /* If there are templates that we've put off instantiating, do
4453 them now. */
4457 /* Write out virtual tables as required. Note that writing out
4458 the virtual table for a template class may cause the
4459 instantiation of members of that class. If we write out
4460 vtables then we remove the class from our list so we don't
4461 have to look at it again. */
4465 {
4468 }
4472 {
4476 {
4478 {
4481 }
4482 else
4486 }
4487 }
4489 /* Write out needed type info variables. We have to be careful
4490 looping through unemitted decls, because emit_tinfo_decl may
4491 cause other variables to be needed. New elements will be
4492 appended, and we remove from the vector those that actually
4493 get emitted. */
4497 {
4500 }
4502 /* The list of objects with static storage duration is built up
4503 in reverse order. We clear STATIC_AGGREGATES so that any new
4504 aggregates added during the initialization of these will be
4505 initialized in the correct order when we next come around the
4506 loop. */
4510 {
4511 /* We need to start a new initialization function each time
4512 through the loop. That's because we need to know which
4513 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4514 isn't computed until a function is finished, and written
4515 out. That's a deficiency in the back end. When this is
4516 fixed, these initialization functions could all become
4517 inline, with resulting performance improvements. */
4518 tree ssdf_body;
4520 /* Set the line and file, so that it is obviously not from
4521 the source file. */
4525 /* Make sure the back end knows about all the variables. */
4528 /* First generate code to do all the initializations. */
4532 /* Then, generate code to do all the destructions. Do these
4533 in reverse order so that the most recently constructed
4534 variable is the first destroyed. If we're using
4535 __cxa_atexit, then we don't need to do this; functions
4536 were registered at initialization time to destroy the
4537 local statics. */
4539 {
4542 }
4543 else
4546 /* Finish up the static storage duration function for this
4547 round. */
4551 /* All those initializations and finalizations might cause
4552 us to need more inline functions, more template
4553 instantiations, etc. */
4555 ssdf_count++;
4556 /* ??? was: locus.line++; */
4557 }
4559 /* Now do the same for thread_local variables. */
4562 /* Go through the set of inline functions whose bodies have not
4563 been emitted yet. If out-of-line copies of these functions
4564 are required, emit them. */
4566 {
4567 /* Does it need synthesizing? */
4570 {
4571 /* Even though we're already at the top-level, we push
4572 there again. That way, when we pop back a few lines
4573 hence, all of our state is restored. Otherwise,
4574 finish_function doesn't clean things up, and we end
4575 up with CURRENT_FUNCTION_DECL set. */
4577 /* The decl's location will mark where it was first
4578 needed. Save that so synthesize method can indicate
4579 where it was needed from, in case of error */
4584 }
4592 /* We lie to the back end, pretending that some functions
4593 are not defined when they really are. This keeps these
4594 functions from being put out unnecessarily. But, we must
4595 stop lying when the functions are referenced, or if they
4596 are not comdat since they need to be put out now. If
4597 DECL_INTERFACE_KNOWN, then we have already set
4598 DECL_EXTERNAL appropriately, so there's no need to check
4599 again, and we do not want to clear DECL_EXTERNAL if a
4600 previous call to import_export_decl set it.
4602 This is done in a separate for cycle, because if some
4603 deferred function is contained in another deferred
4604 function later in deferred_fns varray,
4605 rest_of_compilation would skip this function and we
4606 really cannot expand the same function twice. */
4611 {
4620 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4621 group, we need to mark all symbols in the same comdat group
4622 that way. */
4629 }
4631 /* If we're going to need to write this function out, and
4632 there's already a body for it, create RTL for it now.
4633 (There might be no body if this is a method we haven't
4634 gotten around to synthesizing yet.) */
4639 {
4640 /* We will output the function; no longer consider it in this
4641 loop. */
4643 /* Generate RTL for this function now that we know we
4644 need it. */
4646 /* If we're compiling -fsyntax-only pretend that this
4647 function has been written out so that we don't try to
4648 expand it again. */
4652 }
4653 }
4658 /* Static data members are just like namespace-scope globals. */
4660 {
4662 /* Don't write it out if we haven't seen a definition. */
4666 /* If this static data member is needed, provide it to the
4667 back end. */
4670 }
4676 retries++;
4677 }
4680 /* All used inline functions must have a definition at this point. */
4682 {
4685 /* If the definition actually was available here, then the
4686 fact that the function was not defined merely represents
4687 that for some reason (use of a template repository,
4688 #pragma interface, etc.) we decided not to emit the
4689 definition here. */
4691 /* Don't complain if the template was defined. */
4695 {
4697 /* Avoid a duplicate warning from check_global_declaration_1. */
4699 }
4700 }
4702 /* So must decls that use a type with no linkage. */
4708 /* Then, do the Objective-C stuff. This is where all the
4709 Objective-C module stuff gets generated (symtab,
4710 class/protocol/selector lists etc). This must be done after C++
4711 templates, destructors etc. so that selectors used in C++
4712 templates are properly allocated. */
4716 /* We give C linkage to static constructors and destructors. */
4719 /* Generate initialization and destruction functions for all
4720 priorities for which they are required. */
4723 generate_ctor_and_dtor_functions_for_priority,
4726 /* If this is obj-c++ and we need a static init, call
4727 generate_ctor_or_dtor_function. */
4731 /* We're done with the splay-tree now. */
4735 /* Generate any missing aliases. */
4738 /* We're done with static constructors, so we can go back to "C++"
4739 linkage now. */
4742 /* Collect candidates for Java hidden aliases. */
4749 {
4753 }
4758 {
4759 /* Generate the special constructor initialization function that
4760 calls __VLTRegisterPairs, and give it a very high
4761 initialization priority. This must be done after
4762 finalize_compilation_unit so that we have accurate
4763 information about which vtable will actually be emitted. */
4765 }
4770 /* Now, issue warnings about static, but not defined, functions,
4771 etc., and emit debugging information. */
4774 {
4779 }
4783 /* Generate hidden aliases for Java. */
4785 {
4788 }
4792 /* The entire file is now complete. If requested, dump everything
4793 to a file. */
4797 {
4800 }
4803 #ifdef ENABLE_CHECKING
4808 }
4810 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
4811 function to call in parse-tree form; it has not yet been
4812 semantically analyzed. ARGS are the arguments to the function.
4813 They have already been semantically analyzed. This may change
4814 ARGS. */
4816 tree
4818 tsubst_flags_t complain)
4819 {
4820 tree orig_fn;
4822 tree expr;
4823 tree object;
4829 {
4838 /* Transform the arguments and add the implicit "this"
4839 parameter. That must be done before the FN is transformed
4840 because we depend on the form of FN. */
4844 {
4848 }
4849 /* Now that the arguments are done, transform FN. */
4851 }
4853 /* A qualified name corresponding to a bound pointer-to-member is
4854 represented as an OFFSET_REF:
4856 struct B { void g(); };
4857 void (B::*p)();
4858 void B::g() { (this->*p)(); } */
4860 {
4864 complain);
4866 }
4870 else
4879 }
4882 void
4884 {
4889 {
4893 {
4896 }
4897 }
4898 }
4900 /* Return true if function DECL can be inlined. This is used to force
4901 instantiation of methods that might be interesting for inlining. */
4902 bool
4904 {
4910 /* When optimizing, we might inline everything when flatten
4911 attribute or heuristics inlining for size or autoinlining
4912 is used. */
4914 }
4916 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
4917 If DECL is a specialization or implicitly declared class member,
4918 generate the actual definition. Return false if something goes
4919 wrong, true otherwise. */
4921 bool
4923 {
4924 /* If DECL is a BASELINK for a single function, then treat it just
4925 like the DECL for the function. Otherwise, if the BASELINK is
4926 for an overloaded function, we don't know which function was
4927 actually used until after overload resolution. */
4929 {
4934 }
4936 /* Set TREE_USED for the benefit of -Wunused. */
4941 /* Mark enumeration types as used. */
4950 {
4952 {
4955 {
4956 /* We mark a lambda conversion op as deleted if we can't
4957 generate it properly; see maybe_add_lambda_conv_op. */
4961 }
4962 }
4964 {
4968 }
4970 }
4976 /* We can only check DECL_ODR_USED on variables or functions with
4977 DECL_LANG_SPECIFIC set, and these are also the only decls that we
4978 might need special handling for. */
4982 {
4984 {
4988 }
4990 }
4992 /* We only want to do this processing once. We don't need to keep trying
4993 to instantiate inline templates, because unit-at-a-time will make sure
4994 we get them compiled before functions that want to inline them. */
4998 /* If within finish_function, defer the rest until that function
4999 finishes, otherwise it might recurse. */
5001 {
5004 }
5006 /* Normally, we can wait until instantiation-time to synthesize DECL.
5007 However, if DECL is a static data member initialized with a constant
5008 or a constexpr function, we need it right now because a reference to
5009 such a data member or a call to such function is not value-dependent.
5010 For a function that uses auto in the return type, we need to instantiate
5011 it to find out its type. For OpenMP user defined reductions, we need
5012 them instantiated for reduction clauses which inline them by hand
5013 directly. */
5022 {
5023 /* Instantiating a function will result in garbage collection. We
5024 must treat this situation as if we were within the body of a
5025 function so as to avoid collecting live data only referenced from
5026 the stack (such as overload resolution candidates). */
5031 }
5036 /* Check this too in case we're within instantiate_non_dependent_expr. */
5042 {
5046 }
5048 /* If we don't need a value, then we don't need to synthesize DECL. */
5056 /* DR 757: A type without linkage shall not be used as the type of a
5057 variable or function with linkage, unless
5058 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5059 o the variable or function is not used (3.2 [basic.def.odr]) or is
5060 defined in the same translation unit. */
5067 {
5069 /* There's no way to define a local extern, and adding it to
5070 the vector interferes with GC, so give an error now. */
5072 else
5074 }
5078 /* Remember it, so we can check it was defined. */
5081 /* Is it a synthesized method that needs to be synthesized? */
5085 /* A function defaulted outside the class is synthesized either by
5086 cp_finish_decl or instantiate_decl. */
5089 {
5090 /* Defer virtual destructors so that thunks get the right
5091 linkage. */
5093 {
5096 }
5098 /* Remember the current location for a function we will end up
5099 synthesizing. Then we can inform the user where it was
5100 required in the case of error. */
5103 /* Synthesizing an implicitly defined member function will result in
5104 garbage collection. We must treat this situation as if we were
5105 within the body of a function so as to avoid collecting live data
5106 on the stack (such as overload resolution candidates).
5108 We could just let cp_write_global_declarations handle synthesizing
5109 this function by adding it to deferred_fns, but doing
5110 it at the use site produces better error messages. */
5114 /* If this is a synthesized method we don't need to
5115 do the instantiation test below. */
5116 }
5121 /* If this is a function or variable that is an instance of some
5122 template, we now know that we will need to actually do the
5123 instantiation. We check that DECL is not an explicit
5124 instantiation because that is not checked in instantiate_decl.
5126 We put off instantiating functions in order to improve compile
5127 times. Maintaining a stack of active functions is expensive,
5128 and the inliner knows to instantiate any functions it might
5129 need. Therefore, we always try to defer instantiation. */
5130 {
5135 }
5138 }
5140 bool
5142 {
5144 }
5146 tree
5148 {
5150 }
5152 tree
5154 {
5155 tree fn;
5163 }