| blob | cac0508f881af2e0cd21a135b6d594787d30b328 |
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. */
63 /* This structure contains information about the initializations
64 and/or destructions required for a particular priority level. */
66 /* Nonzero if there have been any initializations at this priority
67 throughout the translation unit. */
69 /* Nonzero if there have been any destructions at this priority
70 throughout the translation unit. */
95 /* A list of static class variables. This is needed, because a
96 static class variable can be declared inside the class without
97 an initializer, and then initialized, statically, outside the class. */
100 /* A list of functions which were declared inline, but which we
101 may need to emit outline anyway. */
104 /* A list of decls that use types with no linkage, which we need to make
105 sure are defined. */
108 /* A vector of alternating decls and identifiers, where the latter
109 is to be an alias for the former if the former is defined. */
112 /* Nonzero if we're done parsing and into end-of-file activities. */
115 \f
117 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a
118 FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers
119 that apply to the function). */
121 tree
123 cp_ref_qualifier rqual)
124 {
125 tree raises;
126 tree attrs;
155 }
157 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its
158 return type changed to NEW_RET. */
160 tree
162 {
163 tree newtype;
176 {
181 }
182 else
183 newtype = build_method_type_directly
195 }
197 /* Build a PARM_DECL with NAME and TYPE, and set DECL_ARG_TYPE
198 appropriately. */
200 tree
202 {
205 /* DECL_ARG_TYPE is only used by the back end and the back end never
206 sees templates. */
211 }
213 /* Returns a PARM_DECL for a parameter of the indicated TYPE, with the
214 indicated NAME. */
216 tree
218 {
221 /* All our artificial parms are implicitly `const'; they cannot be
222 assigned to. */
225 }
227 /* Constructors for types with virtual baseclasses need an "in-charge" flag
228 saying whether this constructor is responsible for initialization of
229 virtual baseclasses or not. All destructors also need this "in-charge"
230 flag, which additionally determines whether or not the destructor should
231 free the memory for the object.
233 This function adds the "in-charge" flag to member function FN if
234 appropriate. It is called from grokclassfn and tsubst.
235 FN must be either a constructor or destructor.
237 The in-charge flag follows the 'this' parameter, and is followed by the
238 VTT parm (if any), then the user-written parms. */
240 void
242 {
245 /* If we've already add the in-charge parameter don't do it again. */
249 /* When processing templates we can't know, in general, whether or
250 not we're going to have virtual baseclasses. */
254 /* We don't need an in-charge parameter for constructors that don't
255 have virtual bases. */
266 /* If this is a subobject constructor or destructor, our caller will
267 pass us a pointer to our VTT. */
269 {
272 /* First add it to DECL_ARGUMENTS between 'this' and the real args... */
276 /* ...and then to TYPE_ARG_TYPES. */
280 }
282 /* Then add the in-charge parm (before the VTT parm). */
288 /* Insert our new parameter(s) into the list. */
291 /* And rebuild the function type. */
293 arg_types);
298 fntype = (cp_build_type_attribute_variant
302 /* Now we've got the in-charge parameter. */
304 }
306 /* Classes overload their constituent function names automatically.
307 When a function name is declared in a record structure,
308 its name is changed to it overloaded name. Since names for
309 constructors and destructors can conflict, we place a leading
310 '$' for destructors.
312 CNAME is the name of the class we are grokking for.
314 FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'.
316 FLAGS contains bits saying what's special about today's
317 arguments. DTOR_FLAG == DESTRUCTOR.
319 If FUNCTION is a destructor, then we must add the `auto-delete' field
320 as a second parameter. There is some hair associated with the fact
321 that we must "declare" this variable in the manner consistent with the
322 way the rest of the arguments were declared.
324 QUALS are the qualifiers for the this pointer. */
326 void
328 {
331 /* Even within an `extern "C"' block, members get C++ linkage. See
332 [dcl.link] for details. */
336 {
340 }
349 }
351 /* Create an ARRAY_REF, checking for the user doing things backwards
352 along the way. DECLTYPE_P is for N3276, as in the parser. */
354 tree
357 {
358 tree type;
359 tree expr;
367 {
374 }
380 /* If they have an `operator[]', use that. */
382 {
388 }
389 else
390 {
393 /* Otherwise, create an ARRAY_REF for a pointer or array type.
394 It is a little-known fact that, if `a' is an array and `i' is
395 an int, you can write `i[a]', which means the same thing as
396 `a[i]'. */
399 else
404 else
419 else
420 {
424 }
430 }
435 }
437 /* Given the cast expression EXP, checking out its validity. Either return
438 an error_mark_node if there was an unavoidable error, return a cast to
439 void for trying to delete a pointer w/ the value 0, or return the
440 call to delete. If DOING_VEC is true, we handle things differently
441 for doing an array delete.
442 Implements ARM $5.3.4. This is called from the parser. */
444 tree
446 tsubst_flags_t complain)
447 {
454 {
460 }
462 /* An array can't have been allocated by new, so complain. */
469 {
473 }
477 /* As of Valley Forge, you can delete a pointer to const. */
479 /* You can't delete functions. */
481 {
485 }
487 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */
489 {
492 }
494 /* Deleting a pointer with the value zero is valid and has no effect. */
500 sfk_deleting_destructor,
502 else
505 complain);
506 }
508 /* Report an error if the indicated template declaration is not the
509 sort of thing that should be a member template. */
511 void
513 {
514 tree decl;
523 {
524 /* The parser rejects template declarations in local classes
525 (with the exception of generic lambdas). */
527 /* The parser rejects any use of virtual in a function template. */
531 /* The debug-information generating code doesn't know what to do
532 with member templates. */
534 }
537 else
539 }
541 /* Return true iff TYPE is a valid Java parameter or return type. */
543 static bool
545 {
552 {
555 {
564 {
570 }
572 }
573 }
575 }
577 /* For a METHOD in a Java class CTYPE, return true if
578 the parameter and return types are valid Java types.
579 Otherwise, print appropriate error messages, and return false. */
581 bool
583 {
589 {
593 }
602 {
605 {
610 }
611 }
613 }
615 /* Sanity check: report error if this function FUNCTION is not
616 really a member of the class (CTYPE) it is supposed to belong to.
617 TEMPLATE_PARMS is used to specify the template parameters of a member
618 template passed as FUNCTION_DECL. If the member template is passed as a
619 TEMPLATE_DECL, it can be NULL since the parameters can be extracted
620 from the declaration. If the function is not a function template, it
621 must be NULL.
622 It returns the original declaration for the function, NULL_TREE if
623 no declaration was found, error_mark_node if an error was emitted. */
625 tree
627 {
630 tree pushed_scope;
636 /* Since this is a specialization of a member template,
637 we're not going to find the declaration in the class.
638 For example, in:
640 struct S { template <typename T> void f(T); };
641 template <> void S::f(int);
643 we're not going to find `S::f(int)', but there's no
644 reason we should, either. We let our callers know we didn't
645 find the method, but we don't complain. */
648 /* Basic sanity check: for a template function, the template parameters
649 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */
651 {
655 {
659 }
661 }
663 /* OK, is this a definition of a member template? */
666 /* [temp.mem]
668 A destructor shall not be a member template. */
670 {
673 }
675 /* We must enter the scope here, because conversion operators are
676 named by target type, and type equivalence relies on typenames
677 resolving within the scope of CTYPE. */
681 {
689 {
696 /* We cannot simply call decls_match because this doesn't
697 work for static member functions that are pretending to
698 be methods, and because the name may have been changed by
699 asm("new_name"). */
701 /* Get rid of the this parameter on functions that become
702 static. */
707 /* A member template definition only matches a member template
708 declaration. */
712 /* ref-qualifier or absence of same must match. */
717 /* While finding a match, same types and params are not enough
718 if the function is versioned. Also check version ("target")
719 attributes. */
724 && (!is_template
733 }
735 {
739 }
750 {
755 {
757 {
760 {
763 }
764 }
765 else
767 }
772 else
775 }
776 }
779 else
786 }
788 /* DECL is a function with vague linkage. Remember it so that at the
789 end of the translation unit we can decide whether or not to emit
790 it. */
792 void
794 {
797 }
799 /* As above, but for variable template instantiations. */
801 void
803 {
805 }
807 /* We have just processed the DECL, which is a static data member.
808 The other parameters are as for cp_finish_decl. */
810 void
813 tree asmspec_tree,
815 {
818 /* We cannot call pushdecl here, because that would fill in the
819 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do
820 the right thing, namely, to put this decl out straight away. */
826 /* We already complained about the template definition. */
830 else
834 {
840 }
849 }
851 /* DECLARATOR and DECLSPECS correspond to a class member. The other
852 parameters are as for cp_finish_decl. Return the DECL for the
853 class member declared. */
855 tree
859 tree asmspec_tree,
860 tree attrlist)
861 {
862 tree value;
865 tree name;
875 /* friend or constructor went bad. */
881 {
884 }
886 /* Pass friendly classes back. */
894 {
896 {
899 }
904 value);
905 }
907 /* Stash away type declarations. */
909 {
914 {
917 /* If this is a typedef that names the class for linkage purposes
918 (7.1.3p8), apply any attributes directly to the type. */
924 }
931 /* It's important that push_template_decl below follows
932 set_underlying_type above so that the created template
933 carries the properly set type of VALUE. */
939 }
944 {
947 }
953 {
955 {
957 {
961 }
963 {
965 {
969 }
970 }
974 {
979 else
981 value);
982 }
983 else
984 {
988 value);
989 else
991 value);
992 }
993 }
998 }
1000 /* Pass friend decls back. */
1006 /* Need to set this before push_template_decl. */
1011 {
1015 }
1022 else
1026 {
1051 /* Pass friends back this way. */
1060 }
1062 }
1064 /* Like `grokfield', but for bitfields.
1065 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */
1067 tree
1070 tree attrlist)
1071 {
1079 /* Pass friendly classes back. */
1086 {
1089 }
1092 {
1095 }
1097 /* Usually, finish_struct_1 catches bitfields with invalid types.
1098 But, in the case of bitfields with function type, we confuse
1099 ourselves into thinking they are member functions, so we must
1100 check here. */
1102 {
1106 }
1109 {
1113 }
1116 {
1119 }
1123 {
1124 /* The width must be an integer type. */
1131 }
1139 }
1141 \f
1142 /* Returns true iff ATTR is an attribute which needs to be applied at
1143 instantiation time rather than template definition time. */
1145 static bool
1147 {
1151 tree arg;
1154 /* Unknown attribute. */
1157 /* Attribute weak handling wants to write out assembly right away. */
1161 /* Attribute unused is applied directly, as it appertains to
1162 decls. */
1166 /* Attribute tls_model wants to modify the symtab. */
1170 /* #pragma omp declare simd attribute needs to be always deferred. */
1175 /* An attribute pack is clearly dependent. */
1179 /* If any of the arguments are dependent expressions, we can't evaluate
1180 the attribute until instantiation time. */
1182 {
1185 /* If the first attribute argument is an identifier, only consider
1186 second and following arguments. Attributes like mode, format,
1187 cleanup and several target specific attributes aren't late
1188 just because they have an IDENTIFIER_NODE as first argument. */
1195 }
1200 {
1203 /* We can't apply any attributes to a completely unknown type until
1204 instantiation time. */
1210 /* Also defer most attributes on dependent types. This is not
1211 necessary in all cases, but is the better default. */
1213 /* But some attributes specifically apply to templates. */
1218 else
1220 }
1221 else
1223 }
1225 /* ATTR_P is a list of attributes. Remove any attributes which need to be
1226 applied at instantiation time and return them. If IS_DEPENDENT is true,
1227 the declaration itself is dependent, so all attributes should be applied
1228 at instantiation time. */
1230 static tree
1232 {
1241 {
1243 {
1249 }
1250 else
1252 }
1255 }
1257 /* Remove any late attributes from the list in ATTR_P and attach them to
1258 DECL_P. */
1260 static void
1262 {
1274 else
1279 /* Merge the late attributes at the beginning with the attribute
1280 list. */
1285 {
1286 /* We've added new attributes directly to the main variant, so
1287 now we need to update all of the other variants to include
1288 these new attributes. */
1289 tree variant;
1292 {
1295 }
1296 }
1297 }
1299 /* Return true iff ATTRS are acceptable attributes to be applied in-place
1300 to a typedef which gives a previously anonymous class or enum a name for
1301 linkage purposes. */
1303 bool
1305 {
1307 {
1311 }
1313 }
1315 /* Like reconstruct_complex_type, but handle also template trees. */
1317 tree
1319 {
1324 {
1328 }
1330 {
1334 }
1336 {
1339 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the
1340 element type qualification will be handled by the recursive
1341 cp_reconstruct_complex_type call and cp_build_qualified_type
1342 for ARRAY_TYPEs changes the element type. */
1344 }
1346 {
1353 }
1355 {
1358 /* The build_method_type_directly() routine prepends 'this' to argument list,
1359 so we must compensate by getting rid of it. */
1360 outer
1361 = build_method_type_directly
1364 }
1366 {
1369 }
1370 else
1381 }
1383 /* Replaces any constexpr expression that may be into the attributes
1384 arguments with their reduced value. */
1386 static void
1388 {
1392 tree attr;
1394 {
1395 tree arg;
1397 {
1401 }
1402 }
1403 }
1405 /* Return true if TYPE is an OpenMP mappable type. */
1406 bool
1408 {
1409 /* Mappable type has to be complete. */
1412 /* Arrays have mappable type if the elements have mappable type. */
1415 /* A mappable type cannot contain virtual members. */
1418 /* All data members must be non-static. */
1420 {
1421 tree field;
1425 /* All fields must have mappable types. */
1429 }
1431 }
1433 /* Like decl_attributes, but handle C++ complexity. */
1435 void
1437 {
1442 /* Add implicit "omp declare target" attribute if requested. */
1447 {
1462 else
1465 }
1468 {
1473 }
1481 {
1482 attributes
1486 }
1487 else
1493 /* Propagate deprecation out to the template. */
1496 {
1502 }
1503 }
1504 \f
1505 /* Walks through the namespace- or function-scope anonymous union
1506 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1507 Returns one of the fields for use in the mangled name. */
1509 static tree
1511 {
1513 tree field;
1515 /* Rather than write the code to handle the non-union case,
1516 just give an error. */
1518 {
1521 }
1526 {
1527 tree decl;
1528 tree ref;
1533 {
1537 }
1547 else
1552 {
1553 tree base;
1569 }
1572 else
1577 }
1580 }
1582 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1583 anonymous union, then all members must be laid out together. PUBLIC_P
1584 is nonzero if this union is not declared static. */
1586 void
1588 {
1589 tree type;
1590 tree main_decl;
1599 /* The VAR_DECL's context is the same as the TYPE's context. */
1606 {
1609 }
1615 {
1618 }
1621 {
1622 /* Use main_decl to set the mangled name. */
1628 }
1632 }
1633 \f
1634 /* Auxiliary functions to make type signatures for
1635 `operator new' and `operator delete' correspond to
1636 what compiler will be expecting. */
1638 tree
1640 {
1647 {
1650 }
1653 {
1655 {
1656 /* [basic.stc.dynamic.allocation]
1658 The first parameter shall not have an associated default
1659 argument. */
1662 /* Throw away the default argument. */
1664 }
1667 {
1670 }
1671 }
1672 else
1680 {
1683 /* Fall through. */
1685 type = build_exception_variant
1688 /* Fall through. */
1690 }
1692 }
1694 tree
1696 {
1703 {
1706 }
1710 {
1715 ptr_type_node);
1716 }
1718 {
1721 /* Fall through. */
1723 type = build_exception_variant
1726 /* Fall through. */
1728 }
1731 }
1732 \f
1733 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1734 and mark them as needed. */
1736 static void
1738 {
1739 tree fnaddr;
1744 {
1745 tree fn;
1751 /* This entry is an offset: a virtual base class offset, a
1752 virtual call offset, an RTTI offset, etc. */
1757 /* When we don't have vcall offsets, we output thunks whenever
1758 we output the vtables that contain them. With vcall offsets,
1759 we know all the thunks we'll need when we emit a virtual
1760 function, so we emit the thunks there instead. */
1764 }
1765 }
1767 /* Set DECL up to have the closest approximation of "initialized common"
1768 linkage available. */
1770 void
1772 {
1777 /* We can just emit function and compiler-generated variables
1778 statically; having multiple copies is (for the most part) only
1779 a waste of space.
1781 There are two correctness issues, however: the address of a
1782 template instantiation with external linkage should be the
1783 same, independent of what translation unit asks for the
1784 address, and this will not hold when we emit multiple copies of
1785 the function. However, there's little else we can do.
1787 Also, by default, the typeinfo implementation assumes that
1788 there will be only one copy of the string used as the name for
1789 each type. Therefore, if weak symbols are unavailable, the
1790 run-time library should perform a more conservative check; it
1791 should perform a string comparison, rather than an address
1792 comparison. */
1794 else
1795 {
1796 /* Static data member template instantiations, however, cannot
1797 have multiple copies. */
1802 {
1805 }
1807 {
1808 /* We can't do anything useful; leave vars for explicit
1809 instantiation. */
1812 }
1813 }
1816 }
1818 /* For win32 we also want to put explicit instantiations in
1819 linkonce sections, so that they will be merged with implicit
1820 instantiations; otherwise we get duplicate symbol errors.
1821 For Darwin we do not want explicit instantiations to be
1822 linkonce. */
1824 void
1826 {
1827 /* We used to say that this was not necessary on targets that support weak
1828 symbols, because the implicit instantiations will defer to the explicit
1829 one. However, that's not actually the case in SVR4; a strong definition
1830 after a weak one is an error. Also, not making explicit
1831 instantiations one_only means that we can end up with two copies of
1832 some template instantiations. */
1836 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1837 we can get away with not emitting them if they aren't used. We need
1838 to for variables so that cp_finish_decl will update their linkage,
1839 because their DECL_INITIAL may not have been set properly yet. */
1844 {
1848 {
1851 /* Mark it needed so we don't forget to emit it. */
1854 }
1855 }
1856 }
1858 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1859 This predicate will give the right answer during parsing of the
1860 function, which other tests may not. */
1862 bool
1864 {
1866 {
1869 }
1870 /* Unfortunately, import_export_decl has not always been called
1871 before the function is processed, so we cannot simply check
1872 DECL_COMDAT. */
1880 /* A local static in an inline effectively has vague linkage. */
1883 else
1885 }
1887 /* Determine whether or not we want to specifically import or export CTYPE,
1888 using various heuristics. */
1890 static void
1892 {
1893 /* -1 for imported, 1 for exported. */
1896 /* It only makes sense to call this function at EOF. The reason is
1897 that this function looks at whether or not the first non-inline
1898 non-abstract virtual member function has been defined in this
1899 translation unit. But, we can't possibly know that until we've
1900 seen the entire translation unit. */
1906 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1907 we will have CLASSTYPE_INTERFACE_ONLY set but not
1908 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1909 heuristic because someone will supply a #pragma implementation
1910 elsewhere, and deducing it here would produce a conflict. */
1920 /* For a template class, without -fimplicit-templates, check the
1921 repository. If the virtual table is assigned to this
1922 translation unit, then export the class; otherwise, import
1923 it. */
1926 {
1927 /* The ABI specifies that the virtual table and associated
1928 information are emitted with the key method, if any. */
1930 /* If weak symbol support is not available, then we must be
1931 careful not to emit the vtable when the key function is
1932 inline. An inline function can be defined in multiple
1933 translation units. If we were to emit the vtable in each
1934 translation unit containing a definition, we would get
1935 multiple definition errors at link-time. */
1938 }
1940 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1941 a definition anywhere else. */
1945 /* Allow back ends the chance to overrule the decision. */
1950 {
1953 }
1954 }
1956 /* Return true if VAR has already been provided to the back end; in that
1957 case VAR should not be modified further by the front end. */
1958 static bool
1960 {
1962 }
1964 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1965 must be emitted in this translation unit. Mark it as such. */
1967 void
1969 {
1972 {
1973 /* Extern inline functions don't become needed when referenced.
1974 If we know a method will be emitted in other TU and no new
1975 functions can be marked reachable, just use the external
1976 definition. */
1980 /* #pragma interface and -frepo code can call mark_needed for
1981 maybe-in-charge 'tors; mark the clones as well. */
1982 tree clone;
1985 }
1987 {
1989 /* C++ frontend use mark_decl_references to force COMDAT variables
1990 to be output that might appear dead otherwise. */
1992 }
1993 }
1995 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
1996 returns true if a definition of this entity should be provided in
1997 this object file. Callers use this function to determine whether
1998 or not to let the back end know that a definition of DECL is
1999 available in this translation unit. */
2001 bool
2003 {
2005 /* This function should only be called at the end of the translation
2006 unit. We cannot be sure of whether or not something will be
2007 COMDAT until that point. */
2010 /* All entities with external linkage that are not COMDAT/EXTERN should be
2011 emitted; they may be referred to from other object files. */
2014 /* Functions marked "dllexport" must be emitted so that they are
2015 visible to other DLLs. */
2020 /* When not optimizing, do not bother to produce definitions for extern
2021 symbols. */
2030 /* If this entity was used, let the back end see it; it will decide
2031 whether or not to emit it into the object file. */
2034 /* Virtual functions might be needed for devirtualization. */
2039 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
2040 reference to DECL might cause it to be emitted later. */
2042 }
2044 /* If necessary, write out the vtables for the dynamic class CTYPE.
2045 Returns true if any vtables were emitted. */
2047 static bool
2049 {
2050 tree vtbl;
2051 tree primary_vtbl;
2055 /* If the vtables for this class have already been emitted there is
2056 nothing more to do. */
2060 /* Ignore dummy vtables made by get_vtable_decl. */
2064 /* On some targets, we cannot determine the key method until the end
2065 of the translation unit -- which is when this function is
2066 called. */
2070 /* See if any of the vtables are needed. */
2072 {
2076 }
2078 {
2079 /* If the references to this class' vtables are optimized away,
2080 still emit the appropriate debugging information. See
2081 dfs_debug_mark. */
2086 }
2088 /* The ABI requires that we emit all of the vtables if we emit any
2089 of them. */
2091 {
2092 /* Mark entities references from the virtual table as used. */
2096 {
2099 LOOKUP_NORMAL);
2101 /* It had better be all done at compile-time. */
2103 }
2105 /* Write it out. */
2109 /* Because we're only doing syntax-checking, we'll never end up
2110 actually marking the variable as written. */
2114 {
2119 }
2120 }
2122 /* Since we're writing out the vtable here, also write the debug
2123 info. */
2127 }
2129 /* A special return value from type_visibility meaning internal
2130 linkage. */
2134 /* walk_tree helper function for type_visibility. */
2136 static tree
2138 {
2141 {
2143 }
2146 {
2149 }
2154 }
2156 /* Returns the visibility of TYPE, which is the minimum visibility of its
2157 component types. */
2159 static int
2161 {
2165 }
2167 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2168 specified (or if VISIBILITY is static). If TMPL is true, this
2169 constraint is for a template argument, and takes precedence
2170 over explicitly-specified visibility on the template. */
2172 static void
2174 {
2176 {
2177 /* extern "C" declarations aren't affected by the anonymous
2178 namespace. */
2180 {
2186 {
2191 }
2195 }
2196 }
2199 {
2201 /* This visibility was not specified. */
2203 }
2204 }
2206 /* Constrain the visibility of DECL based on the visibility of its template
2207 arguments. */
2209 static void
2211 {
2212 /* If this is a template instantiation, check the innermost
2213 template args for visibility constraints. The outer template
2214 args are covered by the class check. */
2218 {
2224 else
2225 {
2233 {
2236 else
2238 }
2239 }
2242 }
2243 }
2245 /* Like c_determine_visibility, but with additional C++-specific
2246 behavior.
2248 Function-scope entities can rely on the function's visibility because
2249 it is set in start_preparsed_function.
2251 Class-scope entities cannot rely on the class's visibility until the end
2252 of the enclosing class definition.
2254 Note that because namespaces have multiple independent definitions,
2255 namespace visibility is handled elsewhere using the #pragma visibility
2256 machinery rather than by decorating the namespace declaration.
2258 The goal is for constraints from the type to give a diagnostic, and
2259 other constraints to be applied silently. */
2261 void
2263 {
2269 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2271 /* Only relevant for names with external linkage. */
2275 /* Cloned constructors and destructors get the same visibility as
2276 the underlying function. That should be set up in
2277 maybe_clone_body. */
2284 {
2289 else
2291 }
2294 else
2297 /* If DECL is a member of a class, visibility specifiers on the
2298 class can influence the visibility of the DECL. */
2301 else
2302 {
2303 /* Not a class member. */
2305 /* Virtual tables have DECL_CONTEXT set to their associated class,
2306 so they are automatically handled above. */
2311 {
2312 /* Local statics and classes get the visibility of their
2313 containing function by default, except that
2314 -fvisibility-inlines-hidden doesn't affect them. */
2317 {
2321 }
2322 else
2323 {
2327 {
2331 }
2332 else
2333 {
2337 }
2338 }
2340 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2341 but have no TEMPLATE_INFO, so don't try to check it. */
2343 }
2346 {
2347 /* Under -fvisibility-ms-compat, types are visible by default,
2348 even though their contents aren't. */
2355 else
2357 }
2359 {
2360 /* tinfo visibility is based on the type it's for. */
2361 constrain_visibility
2364 /* Give the target a chance to override the visibility associated
2365 with DECL. */
2371 }
2373 /* Template instantiations and specializations get visibility based
2376 {
2379 else
2380 {
2381 /* Set default visibility to whatever the user supplied with
2382 #pragma GCC visibility or a namespace visibility attribute. */
2385 }
2386 }
2387 }
2390 {
2391 /* If the specialization doesn't specify visibility, use the
2392 visibility from the template. */
2400 {
2404 {
2408 else
2409 {
2413 }
2414 }
2417 /* Template argument visibility outweighs #pragma or namespace
2418 visibility, but not an explicit attribute. */
2420 {
2423 {
2424 /* A class template member with explicit visibility
2425 overrides the class visibility, so we need to apply
2426 all the levels of template args directly. */
2429 {
2432 }
2433 }
2435 /* Limit visibility based on its template arguments. */
2437 }
2438 }
2439 }
2445 /* Names in an anonymous namespace get internal linkage.
2446 This might change once we implement export. */
2449 {
2450 /* Propagate anonymity from type to decl. */
2455 }
2457 /* DR 757: A type without linkage shall not be used as the type of a
2458 variable or function with linkage, unless
2459 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2460 o the variable or function is not used (3.2 [basic.def.odr]) or is
2461 defined in the same translation unit.
2463 Since non-extern "C" decls need to be defined in the same
2464 translation unit, we can make the type internal. */
2467 /* If visibility changed and DECL already has DECL_RTL, ensure
2468 symbol flags are updated. */
2475 }
2477 /* By default, static data members and function members receive
2478 the visibility of their containing class. */
2480 static void
2482 {
2488 else
2489 {
2490 /* Default to the class visibility. */
2494 }
2496 /* Give the target a chance to override the visibility associated
2497 with DECL. */
2501 /* Construction virtual tables are not exported because
2502 they cannot be referred to from other object files;
2503 their name is not standardized by the ABI. */
2509 }
2511 /* Returns true iff DECL is an inline that should get hidden visibility
2512 because of -fvisibility-inlines-hidden. */
2514 static bool
2516 {
2518 /* Don't do this for inline templates; specializations might not be
2519 inline, and we don't want them to inherit the hidden
2520 visibility. We'll set it here for all inline instantiations. */
2521 && !processing_template_decl
2526 }
2528 /* Constrain the visibility of a class TYPE based on the visibility of its
2529 field types. Warn if any fields require lesser visibility. */
2531 void
2533 {
2534 tree binfo;
2535 tree t;
2544 /* Don't warn about visibility if the class has explicit visibility. */
2550 {
2555 {
2560 }
2567 }
2571 {
2575 {
2580 }
2586 }
2587 }
2589 /* Functions for adjusting the visibility of a tagged type and its nested
2590 types and declarations when it gets a name for linkage purposes from a
2591 typedef. */
2596 /* First reset the visibility of all the types. */
2598 static void
2600 {
2605 }
2606 static void
2608 {
2610 }
2612 /* Then reset the visibility of any static data members or member
2613 functions that use those types. */
2615 static void
2617 {
2626 }
2627 static void
2629 {
2631 {
2633 {
2638 }
2640 {
2646 }
2651 {
2654 /* Also update its name, for cxx_dwarf_name. */
2656 }
2659 }
2660 }
2661 static void
2663 {
2665 }
2666 void
2668 {
2671 }
2673 /* Set up our initial idea of what the linkage of DECL should be. */
2675 void
2677 {
2679 /* We've already made a decision as to how this function will
2682 {
2685 {
2689 /* A non-template inline function with external linkage will
2690 always be COMDAT. As we must eventually determine the
2691 linkage of all functions, and as that causes writes to
2692 the data mapped in from the PCH file, it's advantageous
2693 to mark the functions at this point. */
2697 {
2698 /* This function must have external linkage, as
2699 otherwise DECL_INTERFACE_KNOWN would have been
2700 set. */
2704 }
2705 }
2708 }
2709 }
2711 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2712 for DECL has not already been determined, do so now by setting
2713 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2714 function is called entities with vague linkage whose definitions
2715 are available must have TREE_PUBLIC set.
2717 If this function decides to place DECL in COMDAT, it will set
2718 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2719 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2720 callers defer that decision until it is clear that DECL is actually
2721 required. */
2723 void
2725 {
2734 /* We cannot determine what linkage to give to an entity with vague
2735 linkage until the end of the file. For example, a virtual table
2736 for a class will be defined if and only if the key method is
2737 defined in this translation unit. As a further example, consider
2738 that when compiling a translation unit that uses PCH file with
2739 "-frepo" it would be incorrect to make decisions about what
2740 entities to emit when building the PCH; those decisions must be
2741 delayed until the repository information has been processed. */
2743 /* Object file linkage for explicit instantiations is handled in
2744 mark_decl_instantiated. For static variables in functions with
2745 vague linkage, maybe_commonize_var is used.
2747 Therefore, the only declarations that should be provided to this
2748 function are those with external linkage that are:
2750 * implicit instantiations of function templates
2752 * inline function
2754 * implicit instantiations of static data members of class
2755 templates
2757 * virtual tables
2759 * typeinfo objects
2761 Furthermore, all entities that reach this point must have a
2762 definition available in this translation unit.
2764 The following assertions check these conditions. */
2766 /* Any code that creates entities with TREE_PUBLIC cleared should
2767 also set DECL_INTERFACE_KNOWN. */
2773 else
2777 /* Check that a definition of DECL is available in this translation
2778 unit. */
2781 /* Assume that DECL will not have COMDAT linkage. */
2783 /* Assume that DECL will not be imported into this translation
2784 unit. */
2787 /* See if the repository tells us whether or not to emit DECL in
2788 this translation unit. */
2793 {
2794 /* The repository indicates that this entity should be defined
2795 here. Make sure the back end honors that request. */
2797 /* Output the definition as an ordinary strong definition. */
2801 }
2804 /* We have already decided what to do with this DECL; there is no
2805 need to check anything further. */
2806 ;
2808 {
2820 /* The ABI requires that all virtual tables be emitted with
2821 COMDAT linkage. However, on systems where COMDAT symbols
2822 don't show up in the table of contents for a static
2823 archive, or on systems without weak symbols (where we
2824 approximate COMDAT linkage by using internal linkage), the
2825 linker will report errors about undefined symbols because
2826 it will not see the virtual table definition. Therefore,
2827 in the case that we know that the virtual table will be
2828 emitted in only one translation unit, we make the virtual
2829 table an ordinary definition with external linkage. */
2832 {
2833 /* CLASS_TYPE is being exported from this translation unit,
2834 so DECL should be defined here. */
2836 /* If a class is declared in a header with the "extern
2837 template" extension, then it will not be instantiated,
2838 even in translation units that would normally require
2839 it. Often such classes are explicitly instantiated in
2840 one translation unit. Therefore, the explicit
2841 instantiation must be made visible to other translation
2842 units. */
2844 else
2845 {
2846 /* The generic C++ ABI says that class data is always
2847 COMDAT, even if there is a key function. Some
2848 variants (e.g., the ARM EABI) says that class data
2849 only has COMDAT linkage if the class data might be
2850 emitted in more than one translation unit. When the
2851 key method can be inline and is inline, we still have
2852 to arrange for comdat even though
2853 class_data_always_comdat is false. */
2857 {
2858 /* The ABI requires COMDAT linkage. Normally, we
2859 only emit COMDAT things when they are needed;
2860 make sure that we realize that this entity is
2861 indeed needed. */
2864 }
2865 }
2866 }
2870 else
2872 }
2874 {
2877 {
2883 /* If -fno-rtti was specified, then we cannot be sure
2884 that RTTI information will be emitted with the
2885 virtual table of the class, so we must emit it
2886 wherever it is used. */
2889 else
2890 {
2893 {
2899 {
2902 }
2903 }
2904 else
2906 }
2907 }
2908 else
2910 }
2912 {
2913 /* DECL is an implicit instantiation of a function or static
2914 data member. */
2917 || (flag_implicit_inline_templates
2921 else
2922 /* If we are not implicitly generating templates, then mark
2923 this entity as undefined in this translation unit. */
2925 }
2927 {
2929 {
2933 {
2937 && ! flag_implement_inlines
2943 /* Always make artificials weak. */
2946 else
2948 }
2949 }
2950 else
2952 }
2953 else
2957 {
2958 /* If we are importing DECL into this translation unit, mark is
2959 an undefined here. */
2962 }
2964 {
2965 /* If we decided to put DECL in COMDAT, mark it accordingly at
2966 this point. */
2968 }
2971 }
2973 /* Return an expression that performs the destruction of DECL, which
2974 must be a VAR_DECL whose type has a non-trivial destructor, or is
2975 an array whose (innermost) elements have a non-trivial destructor. */
2977 tree
2979 {
2983 }
2985 /* Returns the initialization guard variable for the variable DECL,
2986 which has static storage duration. */
2988 tree
2990 {
2991 tree sname;
2992 tree guard;
2997 {
2998 tree guard_type;
3000 /* We use a type that is big enough to contain a mutex as well
3001 as an integer counter. */
3006 /* The guard should have the same linkage as what it guards. */
3024 }
3026 }
3028 /* Return an atomic load of src with the appropriate memory model. */
3030 static tree
3032 {
3047 }
3049 /* Return those bits of the GUARD variable that should be set when the
3050 guarded entity is actually initialized. */
3052 static tree
3054 {
3056 {
3057 /* We only set the first byte of the guard, in order to leave room
3058 for a mutex in the high-order bits. */
3061 guard);
3064 guard);
3066 }
3069 }
3071 /* Return an expression which determines whether or not the GUARD
3072 variable has already been initialized. */
3074 tree
3076 {
3077 tree guard_value;
3081 else
3084 /* Mask off all but the low bit. */
3086 {
3092 tf_warning_or_error);
3093 }
3100 tf_warning_or_error);
3101 }
3103 /* Return an expression which sets the GUARD variable, indicating that
3104 the variable being guarded has been initialized. */
3106 tree
3108 {
3109 tree guard_init;
3111 /* Set the GUARD to one. */
3117 tf_warning_or_error);
3118 }
3120 /* Returns true iff we can tell that VAR does not have a dynamic
3121 initializer. */
3123 static bool
3125 {
3126 /* If it's defined in another TU, we can't tell. */
3129 /* If it has a non-trivial destructor, registering the destructor
3130 counts as dynamic initialization. */
3133 /* If it's in this TU, its initializer has been processed, unless
3134 it's a case of self-initialization, then DECL_INITIALIZED_P is
3135 false while the initializer is handled by finish_id_expression. */
3138 /* If it has no initializer or a constant one, it's not dynamic. */
3141 }
3143 /* Returns true iff VAR is a variable that needs uses to be
3144 wrapped for possible dynamic initialization. */
3146 static bool
3148 {
3154 }
3156 /* Get the FUNCTION_DECL for the shared TLS init function for this
3157 translation unit. */
3159 static tree
3161 {
3165 {
3168 void_list_node));
3174 }
3176 }
3178 /* Get a FUNCTION_DECL for the init function for the thread_local
3179 variable VAR. The init function will be an alias to the function
3180 that initializes all the non-local TLS variables in the translation
3181 unit. The init function is only used by the wrapper function. */
3183 static tree
3185 {
3186 /* Only C++11 TLS vars need this init fn. */
3190 /* If -fno-extern-tls-init, assume that we don't need to call
3191 a tls init function for a variable defined in another TU. */
3195 #ifdef ASM_OUTPUT_DEF
3196 /* If the variable is internal, or if we can't generate aliases,
3197 call the local init function directly. */
3199 #endif
3205 {
3208 void_list_node));
3217 {
3219 /* If the variable is defined somewhere else and might have static
3220 initialization, make the init function a weak reference. */
3226 else
3228 }
3238 }
3240 }
3242 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3243 variable VAR. The wrapper function calls the init function (if any) for
3244 VAR and then returns a reference to VAR. The wrapper function is used
3245 in place of VAR everywhere VAR is mentioned. */
3247 tree
3249 {
3250 /* Only C++11 TLS vars need this wrapper fn. */
3257 {
3258 /* A named rvalue reference is an lvalue, so the wrapper should
3259 always return an lvalue reference. */
3268 /* The wrapper is inline and emitted everywhere var is used. */
3271 {
3273 #ifdef HAVE_GAS_HIDDEN
3274 /* Make the wrapper bind locally; there's no reason to share
3275 the wrapper between multiple shared objects. */
3278 #endif
3279 }
3285 #if 0
3286 /* We want CSE to commonize calls to the wrapper, but marking it as
3287 pure is unsafe since it has side-effects. I guess we need a new
3288 ECF flag even weaker than ECF_PURE. FIXME! */
3290 #endif
3295 }
3297 }
3299 /* At EOF, generate the definition for the TLS wrapper function FN:
3301 T& var_wrapper() {
3302 if (init_fn) init_fn();
3303 return var;
3304 } */
3306 static void
3308 {
3313 /* Only call the init fn if there might be one. */
3315 {
3317 /* If init_fn is a weakref, make sure it exists before calling. */
3319 {
3324 tf_warning_or_error);
3326 }
3330 {
3333 }
3334 }
3335 else
3336 /* If there's no initialization, the wrapper is a constant function. */
3341 }
3343 /* Start the process of running a particular set of global constructors
3344 or destructors. Subroutine of do_[cd]tors. Also called from
3345 vtv_start_verification_constructor_init_function. */
3347 static tree
3349 {
3350 tree body;
3351 tree fndecl;
3354 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3357 {
3360 #ifdef JOINER
3362 #else
3364 #endif
3367 }
3368 else
3374 NULL_TREE));
3379 /* Mark as artificial because it's not explicitly in the user's
3380 source code. */
3383 /* Mark this declaration as used to avoid spurious warnings. */
3386 /* Mark this function as a global constructor or destructor. */
3389 else
3395 }
3397 /* Finish the process of running a particular set of global constructors
3398 or destructors. Subroutine of do_[cd]tors. */
3400 static void
3402 {
3403 tree fn;
3405 /* Finish up. */
3410 {
3413 }
3414 else
3415 {
3418 }
3421 }
3423 /* The names of the parameters to the function created to handle
3424 initializations and destructions for objects with static storage
3425 duration. */
3429 /* The name of the function we create to handle initializations and
3430 destructions for objects with static storage duration. */
3433 /* The declaration for the __INITIALIZE_P argument. */
3436 /* The declaration for the __PRIORITY argument. */
3439 /* The declaration for the static storage duration function. */
3442 /* All the static storage duration functions created in this
3443 translation unit. */
3446 /* A map from priority levels to information about that priority
3447 level. There may be many such levels, so efficient lookup is
3448 important. */
3451 /* Begins the generation of the function that will handle all
3452 initialization and destruction of objects with static storage
3453 duration. The function generated takes two parameters of type
3454 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3455 nonzero, it performs initializations. Otherwise, it performs
3456 destructions. It only performs those initializations or
3457 destructions with the indicated __PRIORITY. The generated function
3458 returns no value.
3460 It is assumed that this function will only be called once per
3461 translation unit. */
3463 static tree
3465 {
3466 tree type;
3467 tree body;
3470 /* Create the identifier for this function. It will be of the form
3471 SSDF_IDENTIFIER_<number>. */
3476 NULL_TREE);
3478 /* Create the FUNCTION_DECL itself. */
3481 type);
3485 /* Put this function in the list of functions to be called from the
3486 static constructors and destructors. */
3488 {
3491 /* Take this opportunity to initialize the map from priority
3492 numbers to information about that priority level. */
3495 /*delete_value_fn=*/
3498 /* We always need to generate functions for the
3499 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3500 priorities later, we'll be sure to find the
3501 DEFAULT_INIT_PRIORITY. */
3503 }
3507 /* Create the argument list. */
3508 initialize_p_decl = cp_build_parm_decl
3512 priority_decl = cp_build_parm_decl
3520 /* Put the function in the global scope. */
3523 /* Start the function itself. This is equivalent to declaring the
3524 function as:
3526 static void __ssdf (int __initialize_p, init __priority_p);
3528 It is static because we only need to call this function from the
3529 various constructor and destructor functions for this module. */
3532 SF_PRE_PARSED);
3534 /* Set up the scope of the outermost block in the function. */
3538 }
3540 /* Finish the generation of the function which performs initialization
3541 and destruction of objects with static storage duration. After
3542 this point, no more such objects can be created. */
3544 static void
3546 {
3547 /* Close out the function. */
3550 }
3552 /* Return the information about the indicated PRIORITY level. If no
3553 code to handle this level has yet been generated, generate the
3554 appropriate prologue. */
3556 static priority_info
3558 {
3559 priority_info pi;
3560 splay_tree_node n;
3565 {
3566 /* Create a new priority information structure, and insert it
3567 into the map. */
3574 }
3575 else
3579 }
3581 /* The effective initialization priority of a DECL. */
3583 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3584 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3585 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3587 /* Whether a DECL needs a guard to protect it against multiple
3588 initialization. */
3590 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3591 || DECL_ONE_ONLY (decl) \
3592 || DECL_WEAK (decl)))
3594 /* Called from one_static_initialization_or_destruction(),
3595 via walk_tree.
3596 Walks the initializer list of a global variable and looks for
3597 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3598 and that have their DECL_CONTEXT() == NULL.
3599 For each such temporary variable, set their DECL_CONTEXT() to
3600 the current function. This is necessary because otherwise
3601 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3602 when trying to refer to a temporary variable that does not have
3603 it's DECL_CONTECT() properly set. */
3604 static tree
3608 {
3612 {
3613 tree var;
3621 }
3624 }
3626 /* Set up to handle the initialization or destruction of DECL. If
3627 INITP is nonzero, we are initializing the variable. Otherwise, we
3628 are destroying it. */
3630 static void
3632 {
3634 tree guard;
3636 /* If we are supposed to destruct and there's a trivial destructor,
3637 nothing has to be done. */
3642 /* Trick the compiler into thinking we are at the file and line
3643 where DECL was declared so that error-messages make sense, and so
3644 that the debugger will show somewhat sensible file and line
3645 information. */
3648 /* Make sure temporary variables in the initialiser all have
3649 their DECL_CONTEXT() set to a value different from NULL_TREE.
3650 This can happen when global variables initialisers are built.
3651 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3652 the temporary variables that might have been generated in the
3653 accompagning initialisers is NULL_TREE, meaning the variables have been
3654 declared in the global namespace.
3655 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3656 of the temporaries are set to the current function decl. */
3658 fix_temporary_vars_context_r,
3659 NULL);
3661 /* Because of:
3663 [class.access.spec]
3665 Access control for implicit calls to the constructors,
3666 the conversion functions, or the destructor called to
3667 create and destroy a static data member is performed as
3668 if these calls appeared in the scope of the member's
3669 class.
3671 we pretend we are in a static member function of the class of
3672 which the DECL is a member. */
3674 {
3677 }
3679 /* Assume we don't need a guard. */
3681 /* We need a guard if this is an object with external linkage that
3682 might be initialized in more than one place. (For example, a
3683 static data member of a template, when the data member requires
3684 construction.) */
3686 {
3687 tree guard_cond;
3691 /* When using __cxa_atexit, we just check the GUARD as we would
3692 for a local static. */
3694 {
3695 /* When using __cxa_atexit, we never try to destroy
3696 anything from a static destructor. */
3699 }
3700 /* If we don't have __cxa_atexit, then we will be running
3701 destructors from .fini sections, or their equivalents. So,
3702 we need to know how many times we've tried to initialize this
3703 object. We do initializations only if the GUARD is zero,
3704 i.e., if we are the first to initialize the variable. We do
3705 destructions only if the GUARD is one, i.e., if we are the
3706 last to destroy the variable. */
3708 guard_cond
3710 EQ_EXPR,
3712 guard,
3714 tf_warning_or_error),
3715 integer_one_node,
3716 tf_warning_or_error);
3717 else
3718 guard_cond
3720 EQ_EXPR,
3722 guard,
3724 tf_warning_or_error),
3725 integer_zero_node,
3726 tf_warning_or_error);
3730 }
3733 /* If we're using __cxa_atexit, we have not already set the GUARD,
3734 so we must do so now. */
3738 /* Perform the initialization or destruction. */
3740 {
3742 {
3745 {
3749 }
3750 }
3752 /* If we're using __cxa_atexit, register a function that calls the
3753 destructor for the object. */
3756 }
3757 else
3760 /* Finish the guard if-stmt, if necessary. */
3762 {
3765 }
3767 /* Now that we're done with DECL we don't need to pretend to be a
3768 member of its class any longer. */
3771 }
3773 /* Generate code to do the initialization or destruction of the decls in VARS,
3774 a TREE_LIST of VAR_DECL with static storage duration.
3775 Whether initialization or destruction is performed is specified by INITP. */
3777 static void
3779 {
3782 /* Build the outer if-stmt to check for initialization or destruction. */
3786 EQ_EXPR,
3787 initialize_p_decl,
3788 cond,
3789 tf_warning_or_error);
3792 /* To make sure dynamic construction doesn't access globals from other
3793 compilation units where they might not be yet constructed, for
3794 -fsanitize=address insert __asan_before_dynamic_init call that
3795 prevents access to either all global variables that need construction
3796 in other compilation units, or at least those that haven't been
3797 initialized yet. Variables that need dynamic construction in
3798 the current compilation unit are kept accessible. */
3805 tree priority_if_stmt;
3807 priority_info pi;
3809 /* If we don't need a destructor, there's nothing to do. Avoid
3810 creating a possibly empty if-stmt. */
3812 {
3815 }
3817 /* Remember that we had an initialization or finalization at this
3818 priority. */
3823 else
3826 /* Conditionalize this initialization on being in the right priority
3827 and being initializing/finalizing appropriately. */
3830 EQ_EXPR,
3831 priority_decl,
3833 tf_warning_or_error);
3836 /* Process initializers with same priority. */
3840 /* Do one initialization or destruction. */
3844 /* Finish up the priority if-stmt body. */
3850 /* Revert what __asan_before_dynamic_init did by calling
3851 __asan_after_dynamic_init. */
3855 /* Finish up the init/destruct if-stmt body. */
3858 }
3860 /* VARS is a list of variables with static storage duration which may
3861 need initialization and/or finalization. Remove those variables
3862 that don't really need to be initialized or finalized, and return
3863 the resulting list. The order in which the variables appear in
3864 VARS is in reverse order of the order in which they should actually
3865 be initialized. The list we return is in the unreversed order;
3866 i.e., the first variable should be initialized first. */
3868 static tree
3870 {
3875 {
3880 /* Deal gracefully with error. */
3882 {
3885 }
3887 /* The only things that can be initialized are variables. */
3890 /* If this object is not defined, we don't need to do anything
3891 here. */
3893 {
3896 }
3898 /* Also, if the initializer already contains errors, we can bail
3899 out now. */
3902 {
3905 }
3907 /* This variable is going to need initialization and/or
3908 finalization, so we add it to the list. */
3912 }
3915 }
3917 /* Make sure we have told the back end about all the variables in
3918 VARS. */
3920 static void
3922 {
3923 tree v;
3926 {
3929 {
3932 }
3933 }
3934 }
3936 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
3937 (otherwise) that will initialize all global objects with static
3938 storage duration having the indicated PRIORITY. */
3940 static void
3943 {
3945 tree fndecl;
3946 tree body;
3950 /* ??? */
3951 /* Was: locus->line++; */
3953 /* We use `I' to indicate initialization and `D' to indicate
3954 destruction. */
3957 /* We emit the function lazily, to avoid generating empty
3958 global constructors and destructors. */
3961 /* For Objective-C++, we may need to initialize metadata found in this module.
3962 This must be done _before_ any other static initializations. */
3965 {
3968 }
3970 /* Call the static storage duration function with appropriate
3971 arguments. */
3973 {
3974 /* Calls to pure or const functions will expand to nothing. */
3976 {
3977 tree call;
3984 constructor_p),
3986 priority),
3987 NULL_TREE);
3989 }
3990 }
3992 /* Close out the function. */
3995 }
3997 /* Generate constructor and destructor functions for the priority
3998 indicated by N. */
4000 static int
4002 {
4007 /* Generate the functions themselves, but only if they are really
4008 needed. */
4014 /* Keep iterating. */
4016 }
4018 /* Java requires that we be able to reference a local address for a
4019 method, and not be confused by PLT entries. If supported, create a
4020 hidden alias for all such methods. */
4022 static void
4024 {
4025 #ifndef HAVE_GAS_HIDDEN
4027 #endif
4031 {
4037 {
4038 /* Mangle the name in a predictable way; we need to reference
4039 this from a java compiled object file. */
4050 }
4051 }
4052 }
4054 /* Return C++ property of T, based on given operation OP. */
4056 static int
4058 {
4060 {
4062 {
4070 }
4087 }
4088 }
4090 /* Collect source file references recursively, starting from NAMESPC. */
4092 static void
4094 {
4095 tree t;
4100 /* Iterate over names in this name space. */
4105 /* Dump siblings, if any */
4108 /* Dump children, if any */
4110 }
4112 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4113 starting from NAMESPC. */
4115 static void
4117 {
4121 /* Collect decls from this namespace */
4124 /* Collect siblings, if any */
4127 /* Collect children, if any */
4129 }
4131 /* Returns true iff there is a definition available for variable or
4132 function DECL. */
4134 static bool
4136 {
4139 else
4140 {
4143 }
4144 }
4146 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4148 [expr.const]
4150 An integral constant-expression can only involve ... const
4151 variables of integral or enumeration types initialized with
4152 constant expressions ...
4154 C++0x also allows constexpr variables and temporaries initialized
4155 with constant expressions. We handle the former here, but the latter
4156 are just folded away in cxx_eval_constant_expression.
4158 The standard does not require that the expression be non-volatile.
4159 G++ implements the proposed correction in DR 457. */
4161 bool
4163 {
4167 /* We don't know if a template static data member is initialized with
4168 a constant expression until we instantiate its initializer. Even
4169 in the case of a constexpr variable, we can't treat it as a
4170 constant until its initializer is complete in case it's used in
4171 its own initializer. */
4174 }
4176 /* Returns true if DECL could be a symbolic constant variable, depending on
4177 its initializer. */
4179 bool
4181 {
4189 }
4191 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4192 called from grokfndecl and grokvardecl; in all modes it is called from
4193 cp_write_global_declarations. */
4195 void
4197 {
4199 /* In C++11 it's ok if the decl is defined. */
4203 /* The type that got us on no_linkage_decls must have gotten a name for
4206 /* The type might end up having a typedef name for linkage purposes. */
4209 {
4217 /* DRs 132, 319 and 389 seem to indicate types with
4218 no linkage can only be used to declare extern "C"
4219 entities. Since it's not always an error in the
4220 ISO C++ 90 Standard, we only issue a warning. */
4222 "with no linkage used to declare variable %q#D with "
4224 else
4227 decl);
4232 }
4234 {
4237 "%q#D, declared using local type "
4239 }
4243 else
4246 }
4248 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4250 static void
4252 {
4254 }
4256 /* Clear DECL_EXTERNAL for NODE. */
4258 static bool
4260 {
4263 }
4265 /* Build up the function to run dynamic initializers for thread_local
4266 variables in this translation unit and alias the init functions for the
4267 individual variables to it. */
4269 static void
4271 {
4281 boolean_type_node);
4296 tf_warning_or_error);
4299 tf_warning_or_error));
4301 {
4306 #ifdef ASM_OUTPUT_DEF
4307 /* Output init aliases even with -fno-extern-tls-init. */
4309 {
4313 cgraph_node *alias
4317 }
4318 #endif
4319 }
4325 }
4327 /* We're at the end of compilation, so generate any mangling aliases that
4328 we've been saving up, if DECL is going to be output and ID2 isn't
4329 already taken by another declaration. */
4331 static void
4333 {
4334 /* If there's a declaration already using this mangled name,
4335 don't create a compatibility alias that conflicts. */
4342 /* Don't create an alias to an unreferenced function. */
4354 else
4356 }
4358 /* Note that we might want to emit an alias with the symbol ID2 for DECL at
4359 the end of translation, for compatibility across bugs in the mangling
4360 implementation. */
4362 void
4364 {
4365 #ifdef ASM_OUTPUT_DEF
4368 else
4369 {
4372 }
4373 #endif
4374 }
4376 static void
4378 {
4380 {
4384 }
4385 }
4387 /* The entire file is now complete. If requested, dump everything
4388 to a file. */
4390 static void
4392 {
4397 {
4400 }
4401 }
4405 /* Check the deallocation functions for CODE to see if we want to warn that
4406 only one was defined. */
4408 static void
4410 {
4416 {
4418 /* We're only interested in usual deallocation functions. */
4423 else
4425 }
4432 }
4434 /* Check the global deallocation functions to see if we want to warn about
4435 defining unsized without sized (or vice versa). */
4437 static void
4439 {
4444 }
4446 /* This routine is called at the end of compilation.
4447 Its job is to create all the code needed to initialize and
4448 destroy the global aggregates. We do the destruction
4449 first, since that way we only need to reverse the decls once. */
4451 void
4453 {
4454 tree vars;
4459 tree decl;
4464 /* Bad parse errors. Just forget about it. */
4469 /* This is the point to write out a PCH if we're doing that.
4470 In that case we do not want to do anything else. */
4472 {
4476 }
4483 /* Handle -fdump-ada-spec[-slim] */
4485 {
4488 else
4492 }
4494 /* FIXME - huh? was input_line -= 1;*/
4496 /* We now have to write out all the stuff we put off writing out.
4497 These include:
4499 o Template specializations that we have not yet instantiated,
4500 but which are needed.
4501 o Initialization and destruction for non-local objects with
4502 static storage duration. (Local objects with static storage
4503 duration are initialized when their scope is first entered,
4504 and are cleaned up via atexit.)
4505 o Virtual function tables.
4507 All of these may cause others to be needed. For example,
4508 instantiating one function may cause another to be needed, and
4509 generating the initializer for an object may cause templates to be
4510 instantiated, etc., etc. */
4514 do
4515 {
4516 tree t;
4517 tree decl;
4521 /* If there are templates that we've put off instantiating, do
4522 them now. */
4526 /* Write out virtual tables as required. Note that writing out
4527 the virtual table for a template class may cause the
4528 instantiation of members of that class. If we write out
4529 vtables then we remove the class from our list so we don't
4530 have to look at it again. */
4534 {
4537 }
4541 {
4545 {
4547 {
4550 }
4551 else
4555 }
4556 }
4558 /* Write out needed type info variables. We have to be careful
4559 looping through unemitted decls, because emit_tinfo_decl may
4560 cause other variables to be needed. New elements will be
4561 appended, and we remove from the vector those that actually
4562 get emitted. */
4566 {
4569 }
4571 /* The list of objects with static storage duration is built up
4572 in reverse order. We clear STATIC_AGGREGATES so that any new
4573 aggregates added during the initialization of these will be
4574 initialized in the correct order when we next come around the
4575 loop. */
4579 {
4580 /* We need to start a new initialization function each time
4581 through the loop. That's because we need to know which
4582 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4583 isn't computed until a function is finished, and written
4584 out. That's a deficiency in the back end. When this is
4585 fixed, these initialization functions could all become
4586 inline, with resulting performance improvements. */
4587 tree ssdf_body;
4589 /* Set the line and file, so that it is obviously not from
4590 the source file. */
4594 /* Make sure the back end knows about all the variables. */
4597 /* First generate code to do all the initializations. */
4601 /* Then, generate code to do all the destructions. Do these
4602 in reverse order so that the most recently constructed
4603 variable is the first destroyed. If we're using
4604 __cxa_atexit, then we don't need to do this; functions
4605 were registered at initialization time to destroy the
4606 local statics. */
4608 {
4611 }
4612 else
4615 /* Finish up the static storage duration function for this
4616 round. */
4620 /* All those initializations and finalizations might cause
4621 us to need more inline functions, more template
4622 instantiations, etc. */
4624 ssdf_count++;
4625 /* ??? was: locus_at_end_of_parsing.line++; */
4626 }
4628 /* Now do the same for thread_local variables. */
4631 /* Go through the set of inline functions whose bodies have not
4632 been emitted yet. If out-of-line copies of these functions
4633 are required, emit them. */
4635 {
4636 /* Does it need synthesizing? */
4639 {
4640 /* Even though we're already at the top-level, we push
4641 there again. That way, when we pop back a few lines
4642 hence, all of our state is restored. Otherwise,
4643 finish_function doesn't clean things up, and we end
4644 up with CURRENT_FUNCTION_DECL set. */
4646 /* The decl's location will mark where it was first
4647 needed. Save that so synthesize method can indicate
4648 where it was needed from, in case of error */
4653 }
4661 /* We lie to the back end, pretending that some functions
4662 are not defined when they really are. This keeps these
4663 functions from being put out unnecessarily. But, we must
4664 stop lying when the functions are referenced, or if they
4665 are not comdat since they need to be put out now. If
4666 DECL_INTERFACE_KNOWN, then we have already set
4667 DECL_EXTERNAL appropriately, so there's no need to check
4668 again, and we do not want to clear DECL_EXTERNAL if a
4669 previous call to import_export_decl set it.
4671 This is done in a separate for cycle, because if some
4672 deferred function is contained in another deferred
4673 function later in deferred_fns varray,
4674 rest_of_compilation would skip this function and we
4675 really cannot expand the same function twice. */
4680 {
4689 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4690 group, we need to mark all symbols in the same comdat group
4691 that way. */
4698 }
4700 /* If we're going to need to write this function out, and
4701 there's already a body for it, create RTL for it now.
4702 (There might be no body if this is a method we haven't
4703 gotten around to synthesizing yet.) */
4708 {
4709 /* We will output the function; no longer consider it in this
4710 loop. */
4712 /* Generate RTL for this function now that we know we
4713 need it. */
4715 /* If we're compiling -fsyntax-only pretend that this
4716 function has been written out so that we don't try to
4717 expand it again. */
4721 }
4722 }
4727 /* Static data members are just like namespace-scope globals. */
4729 {
4731 /* Don't write it out if we haven't seen a definition. */
4735 /* If this static data member is needed, provide it to the
4736 back end. */
4739 }
4745 retries++;
4746 }
4751 /* All used inline functions must have a definition at this point. */
4753 {
4756 /* If the definition actually was available here, then the
4757 fact that the function was not defined merely represents
4758 that for some reason (use of a template repository,
4759 #pragma interface, etc.) we decided not to emit the
4760 definition here. */
4762 /* Don't complain if the template was defined. */
4766 {
4768 /* Avoid a duplicate warning from check_global_declaration. */
4770 }
4771 }
4773 /* So must decls that use a type with no linkage. */
4779 /* Then, do the Objective-C stuff. This is where all the
4780 Objective-C module stuff gets generated (symtab,
4781 class/protocol/selector lists etc). This must be done after C++
4782 templates, destructors etc. so that selectors used in C++
4783 templates are properly allocated. */
4787 /* We give C linkage to static constructors and destructors. */
4790 /* Generate initialization and destruction functions for all
4791 priorities for which they are required. */
4794 generate_ctor_and_dtor_functions_for_priority,
4797 /* If this is obj-c++ and we need a static init, call
4798 generate_ctor_or_dtor_function. */
4800 DEFAULT_INIT_PRIORITY,
4803 /* We're done with the splay-tree now. */
4807 /* Generate any missing aliases. */
4810 /* We're done with static constructors, so we can go back to "C++"
4811 linkage now. */
4814 /* Generate Java hidden aliases. */
4818 {
4822 }
4828 /* The entire file is now complete. If requested, dump everything
4829 to a file. */
4833 {
4836 }
4840 }
4842 /* Perform any post compilation-proper cleanups for the C++ front-end.
4843 This should really go away. No front-end should need to do
4844 anything past the compilation process. */
4846 void
4848 {
4852 {
4853 /* Generate the special constructor initialization function that
4854 calls __VLTRegisterPairs, and give it a very high
4855 initialization priority. This must be done after
4856 finalize_compilation_unit so that we have accurate
4857 information about which vtable will actually be emitted. */
4859 }
4863 #ifdef ENABLE_CHECKING
4868 }
4870 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
4871 function to call in parse-tree form; it has not yet been
4872 semantically analyzed. ARGS are the arguments to the function.
4873 They have already been semantically analyzed. This may change
4874 ARGS. */
4876 tree
4878 tsubst_flags_t complain)
4879 {
4880 tree orig_fn;
4882 tree expr;
4883 tree object;
4889 {
4898 /* Transform the arguments and add the implicit "this"
4899 parameter. That must be done before the FN is transformed
4900 because we depend on the form of FN. */
4904 {
4908 }
4909 /* Now that the arguments are done, transform FN. */
4911 }
4913 /* A qualified name corresponding to a bound pointer-to-member is
4914 represented as an OFFSET_REF:
4916 struct B { void g(); };
4917 void (B::*p)();
4918 void B::g() { (this->*p)(); } */
4920 {
4924 complain);
4926 }
4930 else
4939 }
4942 void
4944 {
4949 {
4953 {
4956 }
4957 }
4958 }
4960 /* Return true if function DECL can be inlined. This is used to force
4961 instantiation of methods that might be interesting for inlining. */
4962 bool
4964 {
4970 /* When optimizing, we might inline everything when flatten
4971 attribute or heuristics inlining for size or autoinlining
4972 is used. */
4974 }
4976 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
4977 If DECL is a specialization or implicitly declared class member,
4978 generate the actual definition. Return false if something goes
4979 wrong, true otherwise. */
4981 bool
4983 {
4984 /* If DECL is a BASELINK for a single function, then treat it just
4985 like the DECL for the function. Otherwise, if the BASELINK is
4986 for an overloaded function, we don't know which function was
4987 actually used until after overload resolution. */
4989 {
4994 }
4996 /* Set TREE_USED for the benefit of -Wunused. */
5001 /* Mark enumeration types as used. */
5010 {
5012 {
5015 {
5016 /* We mark a lambda conversion op as deleted if we can't
5017 generate it properly; see maybe_add_lambda_conv_op. */
5021 }
5022 }
5024 {
5028 }
5030 }
5036 /* We can only check DECL_ODR_USED on variables or functions with
5037 DECL_LANG_SPECIFIC set, and these are also the only decls that we
5038 might need special handling for. */
5042 {
5044 {
5048 }
5050 }
5052 /* We only want to do this processing once. We don't need to keep trying
5053 to instantiate inline templates, because unit-at-a-time will make sure
5054 we get them compiled before functions that want to inline them. */
5058 /* If within finish_function, defer the rest until that function
5059 finishes, otherwise it might recurse. */
5061 {
5064 }
5066 /* Normally, we can wait until instantiation-time to synthesize DECL.
5067 However, if DECL is a static data member initialized with a constant
5068 or a constexpr function, we need it right now because a reference to
5069 such a data member or a call to such function is not value-dependent.
5070 For a function that uses auto in the return type, we need to instantiate
5071 it to find out its type. For OpenMP user defined reductions, we need
5072 them instantiated for reduction clauses which inline them by hand
5073 directly. */
5081 {
5082 /* Instantiating a function will result in garbage collection. We
5083 must treat this situation as if we were within the body of a
5084 function so as to avoid collecting live data only referenced from
5085 the stack (such as overload resolution candidates). */
5090 }
5095 /* Check this too in case we're within instantiate_non_dependent_expr. */
5101 {
5105 }
5107 /* If we don't need a value, then we don't need to synthesize DECL. */
5115 /* DR 757: A type without linkage shall not be used as the type of a
5116 variable or function with linkage, unless
5117 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5118 o the variable or function is not used (3.2 [basic.def.odr]) or is
5119 defined in the same translation unit. */
5126 {
5128 /* There's no way to define a local extern, and adding it to
5129 the vector interferes with GC, so give an error now. */
5131 else
5133 }
5137 /* Remember it, so we can check it was defined. */
5140 /* Is it a synthesized method that needs to be synthesized? */
5144 /* A function defaulted outside the class is synthesized either by
5145 cp_finish_decl or instantiate_decl. */
5148 {
5149 /* Defer virtual destructors so that thunks get the right
5150 linkage. */
5152 {
5155 }
5157 /* Remember the current location for a function we will end up
5158 synthesizing. Then we can inform the user where it was
5159 required in the case of error. */
5162 /* Synthesizing an implicitly defined member function will result in
5163 garbage collection. We must treat this situation as if we were
5164 within the body of a function so as to avoid collecting live data
5165 on the stack (such as overload resolution candidates).
5167 We could just let cp_write_global_declarations handle synthesizing
5168 this function by adding it to deferred_fns, but doing
5169 it at the use site produces better error messages. */
5173 /* If this is a synthesized method we don't need to
5174 do the instantiation test below. */
5175 }
5180 /* If this is a function or variable that is an instance of some
5181 template, we now know that we will need to actually do the
5182 instantiation. We check that DECL is not an explicit
5183 instantiation because that is not checked in instantiate_decl.
5185 We put off instantiating functions in order to improve compile
5186 times. Maintaining a stack of active functions is expensive,
5187 and the inliner knows to instantiate any functions it might
5188 need. Therefore, we always try to defer instantiation. */
5189 {
5194 }
5197 }
5199 bool
5201 {
5203 }
5205 tree
5207 {
5209 }
5211 tree
5213 {
5214 tree fn;
5222 }