| blob | 5907b3ce30b8eaf26ed24bb9230029eee695dc26 |
1 /* Subroutines shared by all languages that are variants of C.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
51 /* The following symbols are subsumed in the c_global_trees array, and
52 listed here individually for documentation purposes.
54 INTEGER_TYPE and REAL_TYPE nodes for the standard data types.
56 tree short_integer_type_node;
57 tree long_integer_type_node;
58 tree long_long_integer_type_node;
59 tree int128_integer_type_node;
61 tree short_unsigned_type_node;
62 tree long_unsigned_type_node;
63 tree long_long_unsigned_type_node;
64 tree int128_unsigned_type_node;
66 tree truthvalue_type_node;
67 tree truthvalue_false_node;
68 tree truthvalue_true_node;
70 tree ptrdiff_type_node;
72 tree unsigned_char_type_node;
73 tree signed_char_type_node;
74 tree wchar_type_node;
76 tree char16_type_node;
77 tree char32_type_node;
79 tree float_type_node;
80 tree double_type_node;
81 tree long_double_type_node;
83 tree complex_integer_type_node;
84 tree complex_float_type_node;
85 tree complex_double_type_node;
86 tree complex_long_double_type_node;
88 tree dfloat32_type_node;
89 tree dfloat64_type_node;
90 tree_dfloat128_type_node;
92 tree intQI_type_node;
93 tree intHI_type_node;
94 tree intSI_type_node;
95 tree intDI_type_node;
96 tree intTI_type_node;
98 tree unsigned_intQI_type_node;
99 tree unsigned_intHI_type_node;
100 tree unsigned_intSI_type_node;
101 tree unsigned_intDI_type_node;
102 tree unsigned_intTI_type_node;
104 tree widest_integer_literal_type_node;
105 tree widest_unsigned_literal_type_node;
107 Nodes for types `void *' and `const void *'.
109 tree ptr_type_node, const_ptr_type_node;
111 Nodes for types `char *' and `const char *'.
113 tree string_type_node, const_string_type_node;
115 Type `char[SOMENUMBER]'.
116 Used when an array of char is needed and the size is irrelevant.
118 tree char_array_type_node;
120 Type `int[SOMENUMBER]' or something like it.
121 Used when an array of int needed and the size is irrelevant.
123 tree int_array_type_node;
125 Type `wchar_t[SOMENUMBER]' or something like it.
126 Used when a wide string literal is created.
128 tree wchar_array_type_node;
130 Type `char16_t[SOMENUMBER]' or something like it.
131 Used when a UTF-16 string literal is created.
133 tree char16_array_type_node;
135 Type `char32_t[SOMENUMBER]' or something like it.
136 Used when a UTF-32 string literal is created.
138 tree char32_array_type_node;
140 Type `int ()' -- used for implicit declaration of functions.
142 tree default_function_type;
144 A VOID_TYPE node, packaged in a TREE_LIST.
146 tree void_list_node;
148 The lazily created VAR_DECLs for __FUNCTION__, __PRETTY_FUNCTION__,
149 and __func__. (C doesn't generate __FUNCTION__ and__PRETTY_FUNCTION__
150 VAR_DECLS, but C++ does.)
152 tree function_name_decl_node;
153 tree pretty_function_name_decl_node;
154 tree c99_function_name_decl_node;
156 Stack of nested function name VAR_DECLs.
158 tree saved_function_name_decls;
160 */
163 \f
164 /* Switches common to the C front ends. */
166 /* Nonzero means don't output line number information. */
170 /* Nonzero causes -E output not to be done, but directives such as
171 #define that have side effects are still obeyed. */
175 /* Nonzero means dump macros in some fashion. */
179 /* Nonzero means pass #include lines through to the output. */
183 /* Nonzero means process PCH files while preprocessing. */
187 /* The file name to which we should write a precompiled header, or
188 NULL if no header will be written in this compile. */
192 /* Nonzero if an ISO standard was selected. It rejects macros in the
193 user's namespace. */
196 /* Warn about #pragma directives that are not recognized. */
200 /* Warn about format/argument anomalies in calls to formatted I/O functions
201 (*printf, *scanf, strftime, strfmon, etc.). */
205 /* C/ObjC language option variables. */
208 /* Nonzero means allow type mismatches in conditional expressions;
209 just make their values `void'. */
213 /* Nonzero means enable C89 Amendment 1 features. */
217 /* Nonzero means use the ISO C99 (or C1X) dialect of C. */
221 /* Nonzero means use the ISO C1X dialect of C. */
225 /* Nonzero means that we have builtin functions, and main is an int. */
230 /* ObjC language option variables. */
233 /* Tells the compiler that this is a special run. Do not perform any
234 compiling, instead we are to test some platform dependent features
235 and output a C header file with appropriate definitions. */
239 /* Tells the compiler what is the constant string class for ObjC. */
244 /* C++ language option variables. */
247 /* Nonzero means generate separate instantiation control files and
248 juggle them at link time. */
252 /* The C++ dialect being used. C++98 is the default. */
256 /* Maximum template instantiation depth. This limit exists to limit the
257 time it takes to notice infinite template instantiations; the default
258 value of 1024 is likely to be in the next C++ standard. */
264 /* The elements of `ridpointers' are identifier nodes for the reserved
265 type names and storage classes. It is indexed by a RID_... value. */
270 /* Nonzero means don't warn about problems that occur when the code is
271 executed. */
274 /* Whether lexing has been completed, so subsequent preprocessor
275 errors should use the compiler's input_location. */
278 /* Information about how a function name is generated. */
279 struct fname_var_t
280 {
284 };
286 /* The three ways of getting then name of the current function. */
289 {
290 /* C99 compliant __func__, must be first. */
292 /* GCC __FUNCTION__ compliant. */
294 /* GCC __PRETTY_FUNCTION__ compliant. */
297 };
369 /* Reserved words. The third field is a mask: keywords are disabled
370 if they match the mask.
372 Masks for languages:
373 C --std=c89: D_C99 | D_CXXONLY | D_OBJC | D_CXX_OBJC
374 C --std=c99: D_CXXONLY | D_OBJC
375 ObjC is like C except that D_OBJC and D_CXX_OBJC are not set
376 C++ --std=c98: D_CONLY | D_CXXOX | D_OBJC
377 C++ --std=c0x: D_CONLY | D_OBJC
378 ObjC++ is like C++ except that D_OBJC is not set
380 If -fno-asm is used, D_ASM is added to the mask. If
381 -fno-gnu-keywords is used, D_EXT is added. If -fno-asm and C in
382 C89 mode, D_EXT89 is added for both -fno-asm and -fno-gnu-keywords.
383 In C with -Wc++-compat, we warn if D_CXXWARN is set. */
386 {
526 /* These Objective-C keywords are recognized only immediately after
527 an '@'. */
538 /* These are recognized only in protocol-qualifier context
539 (see above) */
546 };
551 /* Table of machine-independent attributes common to all C-like languages. */
553 {
554 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
556 handle_packed_attribute },
558 handle_nocommon_attribute },
560 handle_common_attribute },
561 /* FIXME: logically, noreturn attributes should be listed as
562 "false, true, true" and apply to function types. But implementing this
563 would require all the places in the compiler that use TREE_THIS_VOLATILE
564 on a decl to identify non-returning functions to be located and fixed
565 to check the function type instead. */
567 handle_noreturn_attribute },
569 handle_noreturn_attribute },
571 handle_noinline_attribute },
573 handle_noclone_attribute },
575 handle_always_inline_attribute },
577 handle_gnu_inline_attribute },
579 handle_artificial_attribute },
581 handle_flatten_attribute },
583 handle_used_attribute },
585 handle_unused_attribute },
587 handle_externally_visible_attribute },
588 /* The same comments as for noreturn attributes apply to const ones. */
590 handle_const_attribute },
592 handle_transparent_union_attribute },
594 handle_constructor_attribute },
596 handle_destructor_attribute },
598 handle_mode_attribute },
600 handle_section_attribute },
602 handle_aligned_attribute },
604 handle_weak_attribute },
606 handle_ifunc_attribute },
608 handle_alias_attribute },
610 handle_weakref_attribute },
612 handle_no_instrument_function_attribute },
614 handle_malloc_attribute },
616 handle_returns_twice_attribute },
618 handle_no_limit_stack_attribute },
620 handle_pure_attribute },
621 /* For internal use (marking of builtins) only. The name contains space
622 to prevent its usage in source code. */
624 handle_novops_attribute },
626 handle_deprecated_attribute },
628 handle_vector_size_attribute },
630 handle_visibility_attribute },
632 handle_tls_model_attribute },
634 handle_nonnull_attribute },
636 handle_nothrow_attribute },
639 handle_cleanup_attribute },
641 handle_warn_unused_result_attribute },
643 handle_sentinel_attribute },
644 /* For internal use (marking of builtins) only. The name contains space
645 to prevent its usage in source code. */
647 handle_type_generic_attribute },
649 handle_alloc_size_attribute },
651 handle_cold_attribute },
653 handle_hot_attribute },
655 handle_error_attribute },
657 handle_error_attribute },
659 handle_target_attribute },
661 handle_optimize_attribute },
663 handle_no_split_stack_attribute },
664 /* For internal use (marking of builtins and runtime functions) only.
665 The name contains space to prevent its usage in source code. */
667 handle_fnspec_attribute },
669 };
671 /* Give the specifications for the format attributes, used by C and all
672 descendants. */
675 {
676 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
678 handle_format_attribute },
680 handle_format_arg_attribute },
682 };
684 /* Return identifier for address space AS. */
688 {
692 }
694 /* Push current bindings for the function name VAR_DECLS. */
696 void
698 {
703 {
707 {
710 }
711 }
713 /* Normally they'll have been NULL, so only push if we've got a
714 stack, or they are non-NULL. */
716 saved_function_name_decls);
717 }
719 /* Finish up the current bindings, adding them into the current function's
720 statement tree. This must be done _before_ finish_stmt_tree is called.
721 If there is no current function, we must be at file scope and no statements
722 are involved. Pop the previous bindings. */
724 void
726 {
735 {
743 }
749 {
750 /* We had saved values, restore them. */
751 tree saved;
754 {
759 }
761 }
763 }
765 /* Return the text name of the current function, suitably prettified
766 by PRETTY_P. Return string must be freed by caller. */
770 {
777 {
780 }
793 {
796 }
799 }
801 /* Return the VAR_DECL for a const char array naming the current
802 function. If the VAR_DECL has not yet been created, create it
803 now. RID indicates how it should be formatted and IDENTIFIER_NODE
804 ID is its name (unfortunately C and C++ hold the RID values of
805 keywords in different places, so we can't derive RID from ID in
806 this language independent code. LOC is the location of the
807 function. */
809 tree
811 {
821 {
822 /* If a tree is built here, it would normally have the lineno of
823 the current statement. Later this tree will be moved to the
824 beginning of the function and this line number will be wrong.
825 To avoid this problem set the lineno to 0 here; that prevents
826 it from appearing in the RTL. */
827 tree stmts;
835 saved_function_name_decls
839 }
844 }
846 /* Given a STRING_CST, give it a suitable array-of-chars data type. */
848 tree
850 {
855 /* Compute the number of elements, for the array type. */
857 {
860 }
862 {
865 }
867 {
870 }
871 else
872 {
875 }
877 /* C89 2.2.4.1, C99 5.2.4.1 (Translation limits). The analogous
878 limit in C++98 Annex B is very large (65536) and is not normative,
879 so we do not diagnose it (warn_overlength_strings is forced off
880 in c_common_post_options). */
882 {
886 /* Translators: The %d after 'ISO C' will be 90 or 99. Do not
887 separate the %d from the 'C'. 'ISO' should not be
888 translated, but it may be moved after 'C%d' in languages
889 where modifiers follow nouns. */
891 "string length %qd is greater than the length %qd "
894 }
896 /* Create the array type for the string constant. The ISO C++
897 standard says that a string literal has type `const char[N]' or
898 `const wchar_t[N]'. We use the same logic when invoked as a C
899 front-end with -Wwrite-strings.
900 ??? We should change the type of an expression depending on the
901 state of a warning flag. We should just be warning -- see how
902 this is handled in the C++ front-end for the deprecated implicit
903 conversion from string literals to `char*' or `wchar_t*'.
905 The C++ front end relies on TYPE_MAIN_VARIANT of a cv-qualified
906 array type being the unqualified version of that type.
907 Therefore, if we are constructing an array of const char, we must
908 construct the matching unqualified array type first. The C front
909 end does not require this, but it does no harm, so we do it
910 unconditionally. */
921 }
922 \f
923 /* Fully fold EXPR, an expression that was not folded (beyond integer
924 constant expressions and null pointer constants) when being built
925 up. If IN_INIT, this is in a static initializer and certain
926 changes are made to the folding done. Clear *MAYBE_CONST if
927 MAYBE_CONST is not NULL and EXPR is definitely not a constant
928 expression because it contains an evaluated operator (in C99) or an
929 operator outside of sizeof returning an integer constant (in C90)
930 not permitted in constant expressions, or because it contains an
931 evaluated arithmetic overflow. (*MAYBE_CONST should typically be
932 set to true by callers before calling this function.) Return the
933 folded expression. Function arguments have already been folded
934 before calling this function, as have the contents of SAVE_EXPR,
935 TARGET_EXPR, BIND_EXPR, VA_ARG_EXPR, OBJ_TYPE_REF and
936 C_MAYBE_CONST_EXPR. */
938 tree
940 {
941 tree ret;
947 /* This function is not relevant to C++ because C++ folds while
948 parsing, and may need changes to be correct for C++ when C++
949 stops folding while parsing. */
956 {
959 }
966 }
968 /* Internal helper for c_fully_fold. EXPR and IN_INIT are as for
969 c_fully_fold. *MAYBE_CONST_OPERANDS is cleared because of operands
970 not permitted, while *MAYBE_CONST_ITSELF is cleared because of
971 arithmetic overflow (for C90, *MAYBE_CONST_OPERANDS is carried from
972 both evaluated and unevaluated subexpressions while
973 *MAYBE_CONST_ITSELF is carried from only evaluated
974 subexpressions). */
976 static tree
979 {
991 /* This function is not relevant to C++ because C++ folds while
992 parsing, and may need changes to be correct for C++ when C++
993 stops folding while parsing. */
997 /* Constants, declarations, statements, errors, SAVE_EXPRs and
998 anything else not counted as an expression cannot usefully be
999 folded further at this point. */
1005 /* Operands of variable-length expressions (function calls) have
1006 already been folded, as have __builtin_* function calls, and such
1007 expressions cannot occur in constant expressions. */
1009 {
1013 }
1016 {
1025 else
1028 }
1030 /* Assignment, increment, decrement, function call and comma
1031 operators, and statement expressions, cannot occur in constant
1032 expressions if evaluated / outside of sizeof. (Function calls
1033 were handled above, though VA_ARG_EXPR is treated like a function
1034 call here, and statement expressions are handled through
1035 C_MAYBE_CONST_EXPR to avoid folding inside them.) */
1037 {
1057 }
1059 /* Fold individual tree codes as appropriate. */
1061 {
1063 /* Any non-constancy will have been marked in a containing
1064 C_MAYBE_CONST_EXPR; there is no more folding to do here. */
1072 maybe_const_itself);
1077 {
1080 }
1089 maybe_const_itself);
1092 maybe_const_itself);
1098 {
1102 }
1144 /* Binary operations evaluating both arguments (increment and
1145 decrement are binary internally in GCC). */
1149 maybe_const_itself);
1157 /* The RHS of a MODIFY_EXPR was fully folded when building that
1158 expression for the sake of conversion warnings. */
1161 maybe_const_itself);
1165 ret = in_init
1168 else
1179 CASE_CONVERT:
1188 /* Unary operations. */
1191 maybe_const_itself);
1196 ret = in_init
1199 else
1204 {
1208 }
1210 {
1213 CASE_CONVERT:
1214 /* Don't warn about explicit conversions. We will already
1215 have warned about suspect implicit conversions. */
1222 }
1227 /* Binary operations not necessarily evaluating both
1228 arguments. */
1235 ? truthvalue_false_node
1243 ret = in_init
1246 else
1251 && op0_const
1252 && op0_const_self
1258 && op0_const_self
1284 else
1289 && op0_const
1290 && op0_const_self
1294 && op0_const_self
1298 && op0_const
1299 && op0_const_self
1303 && op0_const_self
1309 /* Each case where an operand with excess precision may be
1310 encountered must remove the EXCESS_PRECISION_EXPR around
1311 inner operands and possibly put one around the whole
1312 expression or possibly convert to the semantic type (which
1313 c_fully_fold does); we cannot tell at this stage which is
1314 appropriate in any particular case. */
1318 /* Various codes may appear through folding built-in functions
1319 and their arguments. */
1321 }
1323 out:
1324 /* Some folding may introduce NON_LVALUE_EXPRs; all lvalue checks
1325 have been done by this point, so remove them again. */
1329 {
1333 }
1337 }
1339 /* If not optimizing, EXP is not a VAR_DECL, or EXP has array type,
1340 return EXP. Otherwise, return either EXP or its known constant
1341 value (if it has one), but return EXP if EXP has mode BLKmode. ???
1342 Is the BLKmode test appropriate? */
1344 tree
1346 {
1347 tree ret;
1349 /* This function is only used by C, for c_fully_fold and other
1350 optimization, and may not be correct for C++. */
1361 /* Avoid unwanted tree sharing between the initializer and current
1362 function's body where the tree can be modified e.g. by the
1363 gimplifier. */
1367 }
1369 /* Print a warning if a constant expression had overflow in folding.
1370 Invoke this function on every expression that the language
1371 requires to be a constant expression.
1372 Note the ANSI C standard says it is erroneous for a
1373 constant expression to overflow. */
1375 void
1377 {
1385 }
1387 /* The same as above but print an unconditional error. */
1388 void
1390 {
1397 }
1399 /* Print a warning if an expression had overflow in folding and its
1400 operands hadn't.
1402 Invoke this function on every expression that
1403 (1) appears in the source code, and
1404 (2) is a constant expression that overflowed, and
1405 (3) is not already checked by convert_and_check;
1406 however, do not invoke this function on operands of explicit casts
1407 or when the expression is the result of an operator and any operand
1408 already overflowed. */
1410 void
1412 {
1417 {
1446 }
1447 }
1449 /* Warn about uses of logical || / && operator in a context where it
1450 is likely that the bitwise equivalent was intended by the
1451 programmer. We have seen an expression in which CODE is a binary
1452 operator used to combine expressions OP_LEFT and OP_RIGHT, which before folding
1453 had CODE_LEFT and CODE_RIGHT, into an expression of type TYPE. */
1454 void
1458 {
1470 /* Warn if &&/|| are being used in a context where it is
1471 likely that the bitwise equivalent was intended by the
1472 programmer. That is, an expression such as op && MASK
1473 where op should not be any boolean expression, nor a
1474 constant, and mask seems to be a non-boolean integer constant. */
1482 {
1486 else
1491 }
1493 /* We do not warn for constants because they are typical of macro
1494 expansions that test for features. */
1498 /* This warning only makes sense with logical operands. */
1514 /* If this is an OR operation, invert both sides; we will invert
1515 again at the end. */
1519 /* If both expressions are the same, if we can merge the ranges, and we
1520 can build the range test, return it or it inverted. */
1526 {
1532 "logical %<or%> "
1534 else
1536 "logical %<and%> "
1538 }
1539 }
1542 /* Print a warning about casts that might indicate violation
1543 of strict aliasing rules if -Wstrict-aliasing is used and
1544 strict aliasing mode is in effect. OTYPE is the original
1545 TREE_TYPE of EXPR, and TYPE the type we're casting to. */
1547 bool
1549 {
1550 /* Strip pointer conversion chains and get to the correct original type. */
1558 /* If the type we are casting to is a ref-all pointer
1559 dereferencing it is always valid. */
1566 {
1567 /* Casting the address of an object to non void pointer. Warn
1568 if the cast breaks type based aliasing. */
1570 {
1574 }
1575 else
1576 {
1577 /* warn_strict_aliasing >= 3. This includes the default (3).
1578 Only warn if the cast is dereferenced immediately. */
1579 alias_set_type set1 =
1585 {
1589 }
1592 {
1596 }
1597 }
1598 }
1599 else
1601 {
1602 /* At this level, warn for any conversions, even if an address is
1603 not taken in the same statement. This will likely produce many
1604 false positives, but could be useful to pinpoint problems that
1605 are not revealed at higher levels. */
1610 {
1614 }
1615 }
1618 }
1620 /* Warn for unlikely, improbable, or stupid DECL declarations
1621 of `main'. */
1623 void
1625 {
1626 tree args;
1631 {
1639 {
1643 decl);
1652 decl);
1663 }
1664 }
1666 /* It is intentional that this message does not mention the third
1667 argument because it's only mentioned in an appendix of the
1668 standard. */
1671 }
1673 /* True if pointers to distinct types T1 and T2 can be converted to
1674 each other without an explicit cast. Only returns true for opaque
1675 vector types. */
1676 bool
1678 {
1685 }
1687 /* True if vector types T1 and T2 can be converted to each other
1688 without an explicit cast. If EMIT_LAX_NOTE is true, and T1 and T2
1689 can only be converted with -flax-vector-conversions yet that is not
1690 in effect, emit a note telling the user about that option if such
1691 a note has not previously been emitted. */
1692 bool
1694 {
1702 convertible_lax =
1717 {
1720 "conversions between vectors with differing "
1722 }
1725 }
1727 /* This is a helper function of build_binary_op.
1729 For certain operations if both args were extended from the same
1730 smaller type, do the arithmetic in that type and then extend.
1732 BITWISE indicates a bitwise operation.
1733 For them, this optimization is safe only if
1734 both args are zero-extended or both are sign-extended.
1735 Otherwise, we might change the result.
1736 Eg, (short)-1 | (unsigned short)-1 is (int)-1
1737 but calculated in (unsigned short) it would be (unsigned short)-1.
1738 */
1740 {
1744 tree type;
1746 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents
1747 excessive narrowing when we call get_narrower below. For
1748 example, suppose that OP0 is of unsigned int extended
1749 from signed char and that RESULT_TYPE is long long int.
1750 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look
1751 like
1753 (long long int) (unsigned int) signed_char
1755 which get_narrower would narrow down to
1757 (unsigned int) signed char
1759 If we do not cast OP0 first, get_narrower would return
1760 signed_char, which is inconsistent with the case of the
1761 explicit cast. */
1768 /* UNS is 1 if the operation to be done is an unsigned one. */
1771 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
1772 but it *requires* conversion to FINAL_TYPE. */
1783 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
1785 /* For bitwise operations, signedness of nominal type
1786 does not matter. Consider only how operands were extended. */
1790 /* Note that in all three cases below we refrain from optimizing
1791 an unsigned operation on sign-extended args.
1792 That would not be valid. */
1794 /* Both args variable: if both extended in same way
1795 from same width, do it in that width.
1796 Do it unsigned if args were zero-extended. */
1803 return c_common_signed_or_unsigned_type
1810 && (type
1821 && (type
1829 }
1831 /* Warns if the conversion of EXPR to TYPE may alter a value.
1832 This is a helper function for warnings_for_convert_and_check. */
1834 static void
1836 {
1848 /* If any operand is artificial, then this expression was generated
1849 by the compiler and we do not warn. */
1851 {
1855 }
1858 {
1871 /* Conversion from boolean to a signed:1 bit-field (which only
1872 can hold the values 0 and -1) doesn't lose information - but
1873 it does change the value. */
1882 /* Warn for real constant that is not an exact integer converted
1883 to integer type. */
1886 {
1889 }
1890 /* Warn for an integer constant that does not fit into integer type. */
1894 {
1902 else
1904 }
1906 {
1907 /* Warn for an integer constant that does not fit into real type. */
1909 {
1913 }
1914 /* Warn for a real constant that does not fit into a smaller
1915 real type. */
1918 {
1922 }
1923 }
1933 {
1934 /* In case of COND_EXPR, if both operands are constants or
1935 COND_EXPR, then we do not care about the type of COND_EXPR,
1936 only about the conversion of each operand. */
1944 {
1948 }
1949 /* Fall through. */
1950 }
1954 /* Warn for real types converted to integer types. */
1961 {
1962 /* Don't warn about unsigned char y = 0xff, x = (int) y; */
1966 /* Don't warn for short y; short x = ((int)y & 0xff); */
1970 {
1971 /* If both args were extended from a shortest type,
1972 use that type if that is safe. */
1979 {
1985 /* If one of the operands is a non-negative constant
1986 that fits in the target type, then the type of the
1987 other operand does not matter. */
1996 /* If constant is unsigned and fits in the target
1997 type, then the result will also fit. */
1999 && unsigned0
2002 && unsigned1
2005 }
2006 }
2007 /* Warn for integer types converted to smaller integer types. */
2011 /* When they are the same width but different signedness,
2012 then the value may change. */
2015 /* Even when converted to a bigger type, if the type is
2016 unsigned but expr is signed, then negative values
2017 will be changed. */
2022 }
2024 /* Warn for integer types converted to real types if and only if
2025 all the range of values of the integer type cannot be
2026 represented by the real type. */
2029 {
2033 /* Don't warn about char y = 0xff; float x = (int) y; */
2045 }
2047 /* Warn for real types converted to smaller real types. */
2058 }
2059 }
2061 /* Produce warnings after a conversion. RESULT is the result of
2062 converting EXPR to TYPE. This is a helper function for
2063 convert_and_check and cp_convert_and_check. */
2065 void
2067 {
2072 {
2073 /* Do not diagnose overflow in a constant expression merely
2074 because a conversion overflowed. */
2079 {
2080 /* This detects cases like converting -129 or 256 to
2081 unsigned char. */
2085 else
2087 }
2091 /* No warning for converting 0x80000000 to int. */
2099 else
2101 }
2106 else
2108 }
2111 /* Convert EXPR to TYPE, warning about conversion problems with constants.
2112 Invoke this function on every expression that is converted implicitly,
2113 i.e. because of language rules and not because of an explicit cast. */
2115 tree
2117 {
2118 tree result;
2119 tree expr_for_warning;
2121 /* Convert from a value with possible excess precision rather than
2122 via the semantic type, but do not warn about values not fitting
2123 exactly in the semantic type. */
2125 {
2131 }
2132 else
2146 }
2147 \f
2148 /* A node in a list that describes references to variables (EXPR), which are
2149 either read accesses if WRITER is zero, or write accesses, in which case
2150 WRITER is the parent of EXPR. */
2151 struct tlist
2152 {
2155 };
2157 /* Used to implement a cache the results of a call to verify_tree. We only
2158 use this for SAVE_EXPRs. */
2159 struct tlist_cache
2160 {
2164 tree expr;
2165 };
2167 /* Obstack to use when allocating tlist structures, and corresponding
2168 firstobj. */
2172 /* Keep track of the identifiers we've warned about, so we can avoid duplicate
2173 warnings. */
2175 /* SAVE_EXPRs need special treatment. We process them only once and then
2176 cache the results. */
2188 /* Create a new struct tlist and fill in its fields. */
2191 {
2198 }
2200 /* Add duplicates of the nodes found in ADD to the list *TO. If EXCLUDE_WRITER
2201 is nonnull, we ignore any node we find which has a writer equal to it. */
2203 static void
2205 {
2207 {
2214 }
2215 }
2217 /* Merge the nodes of ADD into TO. This merging process is done so that for
2218 each variable that already exists in TO, no new node is added; however if
2219 there is a write access recorded in ADD, and an occurrence on TO is only
2220 a read access, then the occurrence in TO will be modified to record the
2221 write. */
2223 static void
2225 {
2232 {
2239 {
2243 }
2245 {
2249 }
2251 }
2252 }
2254 /* WRITTEN is a variable, WRITER is its parent. Warn if any of the variable
2255 references in list LIST conflict with it, excluding reads if ONLY writers
2256 is nonzero. */
2258 static void
2261 {
2264 /* Avoid duplicate warnings. */
2270 {
2274 {
2280 }
2282 }
2283 }
2285 /* Given a list LIST of references to variables, find whether any of these
2286 can cause conflicts due to missing sequence points. */
2288 static void
2290 {
2294 {
2297 }
2298 }
2300 /* Return nonzero if X is a tree that can be verified by the sequence point
2301 warnings. */
2302 static int
2304 {
2305 /* !VOID_TYPE_P (TREE_TYPE (x)) is workaround for cp/tree.c
2306 (lvalue_p) crash on TRY/CATCH. */
2309 }
2311 /* Return nonzero if X and Y appear to be the same candidate (or NULL) */
2312 static bool
2314 {
2316 }
2318 /* Walk the tree X, and record accesses to variables. If X is written by the
2319 parent tree, WRITER is the parent.
2320 We store accesses in one of the two lists: PBEFORE_SP, and PNO_SP. If this
2321 expression or its only operand forces a sequence point, then everything up
2322 to the sequence point is stored in PBEFORE_SP. Everything else gets stored
2323 in PNO_SP.
2324 Once we return, we will have emitted warnings if any subexpression before
2325 such a sequence point could be undefined. On a higher level, however, the
2326 sequence point may not be relevant, and we'll merge the two lists.
2328 Example: (b++, a) + b;
2329 The call that processes the COMPOUND_EXPR will store the increment of B
2330 in PBEFORE_SP, and the use of A in PNO_SP. The higher-level call that
2331 processes the PLUS_EXPR will need to merge the two lists so that
2332 eventually, all accesses end up on the same list (and we'll warn about the
2333 unordered subexpressions b++ and b.
2335 A note on merging. If we modify the former example so that our expression
2336 becomes
2337 (b++, b) + a
2338 care must be taken not simply to add all three expressions into the final
2339 PNO_SP list. The function merge_tlist takes care of that by merging the
2340 before-SP list of the COMPOUND_EXPR into its after-SP list in a special
2341 way, so that no more than one access to B is recorded. */
2343 static void
2345 tree writer)
2346 {
2351 /* X may be NULL if it is the operand of an empty statement expression
2352 ({ }). */
2356 restart:
2364 {
2396 /* Rather than add both tmp_nosp and tmp_list2, we have to merge the
2397 two first, to avoid warning for (a ? b++ : b++). */
2413 /* Expressions inside the LHS are not ordered wrt. the sequence points
2414 in the RHS. Example:
2415 *a = (a++, 2)
2416 Despite the fact that the modification of "a" is in the before_sp
2417 list (tmp_before), it conflicts with the use of "a" in the LHS.
2418 We can handle this by adding the contents of tmp_list3
2419 to those of tmp_before, and redoing the collision warnings for that
2420 list. */
2423 /* Exclude the LHS itself here; we first have to merge it into the
2424 tmp_nosp list. This is done to avoid warning for "a = a"; if we
2425 didn't exclude the LHS, we'd get it twice, once as a read and once
2426 as a write. */
2437 /* We need to warn about conflicts among arguments and conflicts between
2438 args and the function address. Side effects of the function address,
2439 however, are not ordered by the sequence point of the call. */
2440 {
2441 call_expr_arg_iterator iter;
2442 tree arg;
2446 {
2451 }
2456 }
2459 /* Scan all the list, e.g. indices of multi dimensional array. */
2461 {
2467 }
2471 {
2478 {
2490 {
2494 }
2497 }
2501 }
2511 /* For other expressions, simply recurse on their operands.
2512 Manual tail recursion for unary expressions.
2513 Other non-expressions need not be processed. */
2515 {
2519 }
2521 {
2525 {
2530 }
2531 }
2533 }
2534 }
2536 /* Try to warn for undefined behavior in EXPR due to missing sequence
2537 points. */
2539 DEBUG_FUNCTION void
2541 {
2547 {
2550 }
2555 }
2556 \f
2557 /* Validate the expression after `case' and apply default promotions. */
2559 static tree
2561 {
2565 /* ??? Can we ever get nops here for a valid case value? We
2566 shouldn't for C. */
2568 /* In C++, the following is allowed:
2570 const int i = 3;
2571 switch (...) { case i: ... }
2573 So, we try to reduce the VALUE to a constant that way. */
2575 {
2579 }
2582 /* Promote char or short to int. */
2585 {
2588 }
2593 }
2594 \f
2595 /* See if the case values LOW and HIGH are in the range of the original
2596 type (i.e. before the default conversion to int) of the switch testing
2597 expression.
2598 TYPE is the promoted type of the testing expression, and ORIG_TYPE is
2599 the type before promoting it. CASE_LOW_P is a pointer to the lower
2600 bound of the case label, and CASE_HIGH_P is the upper bound or NULL
2601 if the case is not a case range.
2602 The caller has to make sure that we are not called with NULL for
2603 CASE_LOW_P (i.e. the default case).
2604 Returns true if the case label is in range of ORIG_TYPE (saturated or
2605 untouched) or false if the label is out of range. */
2607 static bool
2610 {
2615 /* If there was a problem with the original type, do nothing. */
2622 /* Case label is less than minimum for type. */
2625 {
2628 }
2630 /* Case value is greater than maximum for type. */
2633 {
2636 }
2638 /* Saturate lower case label value to minimum. */
2641 {
2645 }
2647 /* Saturate upper case label value to maximum. */
2650 {
2654 }
2662 }
2663 \f
2664 /* Return an integer type with BITS bits of precision,
2665 that is unsigned if UNSIGNEDP is nonzero, otherwise signed. */
2667 tree
2669 {
2708 }
2710 /* Return a fixed-point type that has at least IBIT ibits and FBIT fbits
2711 that is unsigned if UNSIGNEDP is nonzero, otherwise signed;
2712 and saturating if SATP is nonzero, otherwise not saturating. */
2714 tree
2717 {
2721 else
2729 {
2731 "fixed-point types that have too many integral and "
2734 }
2737 }
2739 /* Used for communication between c_common_type_for_mode and
2740 c_register_builtin_type. */
2743 /* Return a data type that has machine mode MODE.
2744 If the mode is an integer,
2745 then UNSIGNEDP selects between signed and unsigned types.
2746 If the mode is a fixed-point mode,
2747 then UNSIGNEDP selects between saturating and nonsaturating types. */
2749 tree
2751 {
2752 tree t;
2789 #if HOST_BITS_PER_WIDE_INT >= 64
2792 #endif
2817 {
2819 tree inner_type;
2835 }
2837 {
2842 }
2852 {
2938 }
2945 }
2947 tree
2949 {
2951 }
2953 /* Return a signed type the same as TYPE in other respects. */
2955 tree
2957 {
2959 }
2961 /* Return a type the same as TYPE except unsigned or
2962 signed according to UNSIGNEDP. */
2964 tree
2966 {
2967 tree type1;
2969 /* This block of code emulates the behavior of the old
2970 c_common_unsigned_type. In particular, it returns
2971 long_unsigned_type_node if passed a long, even when a int would
2972 have the same size. This is necessary for warnings to work
2973 correctly in archs where sizeof(int) == sizeof(long) */
2976 if (type1 == signed_char_type_node || type1 == char_type_node || type1 == unsigned_char_type_node)
2992 #if HOST_BITS_PER_WIDE_INT >= 64
2995 #endif
3005 #define C_COMMON_FIXED_TYPES(NAME) \
3006 if (type1 == short_ ## NAME ## _type_node \
3007 || type1 == unsigned_short_ ## NAME ## _type_node) \
3008 return unsignedp ? unsigned_short_ ## NAME ## _type_node \
3009 : short_ ## NAME ## _type_node; \
3010 if (type1 == NAME ## _type_node \
3011 || type1 == unsigned_ ## NAME ## _type_node) \
3012 return unsignedp ? unsigned_ ## NAME ## _type_node \
3013 : NAME ## _type_node; \
3014 if (type1 == long_ ## NAME ## _type_node \
3015 || type1 == unsigned_long_ ## NAME ## _type_node) \
3016 return unsignedp ? unsigned_long_ ## NAME ## _type_node \
3017 : long_ ## NAME ## _type_node; \
3018 if (type1 == long_long_ ## NAME ## _type_node \
3019 || type1 == unsigned_long_long_ ## NAME ## _type_node) \
3020 return unsignedp ? unsigned_long_long_ ## NAME ## _type_node \
3021 : long_long_ ## NAME ## _type_node;
3023 #define C_COMMON_FIXED_MODE_TYPES(NAME) \
3024 if (type1 == NAME ## _type_node \
3025 || type1 == u ## NAME ## _type_node) \
3026 return unsignedp ? u ## NAME ## _type_node \
3027 : NAME ## _type_node;
3029 #define C_COMMON_FIXED_TYPES_SAT(NAME) \
3030 if (type1 == sat_ ## short_ ## NAME ## _type_node \
3031 || type1 == sat_ ## unsigned_short_ ## NAME ## _type_node) \
3032 return unsignedp ? sat_ ## unsigned_short_ ## NAME ## _type_node \
3033 : sat_ ## short_ ## NAME ## _type_node; \
3034 if (type1 == sat_ ## NAME ## _type_node \
3035 || type1 == sat_ ## unsigned_ ## NAME ## _type_node) \
3036 return unsignedp ? sat_ ## unsigned_ ## NAME ## _type_node \
3037 : sat_ ## NAME ## _type_node; \
3038 if (type1 == sat_ ## long_ ## NAME ## _type_node \
3039 || type1 == sat_ ## unsigned_long_ ## NAME ## _type_node) \
3040 return unsignedp ? sat_ ## unsigned_long_ ## NAME ## _type_node \
3041 : sat_ ## long_ ## NAME ## _type_node; \
3042 if (type1 == sat_ ## long_long_ ## NAME ## _type_node \
3043 || type1 == sat_ ## unsigned_long_long_ ## NAME ## _type_node) \
3044 return unsignedp ? sat_ ## unsigned_long_long_ ## NAME ## _type_node \
3045 : sat_ ## long_long_ ## NAME ## _type_node;
3047 #define C_COMMON_FIXED_MODE_TYPES_SAT(NAME) \
3048 if (type1 == sat_ ## NAME ## _type_node \
3049 || type1 == sat_ ## u ## NAME ## _type_node) \
3050 return unsignedp ? sat_ ## u ## NAME ## _type_node \
3051 : sat_ ## NAME ## _type_node;
3077 /* For ENUMERAL_TYPEs in C++, must check the mode of the types, not
3078 the precision; they have precision set to match their range, but
3079 may use a wider mode to match an ABI. If we change modes, we may
3080 wind up with bad conversions. For INTEGER_TYPEs in C, must check
3081 the precision as well, so as to yield correct results for
3082 bit-field types. C++ does not have these separate bit-field
3083 types, and producing a signed or unsigned variant of an
3084 ENUMERAL_TYPE may cause other problems as well. */
3090 #define TYPE_OK(node) \
3091 (TYPE_MODE (type) == TYPE_MODE (node) \
3092 && TYPE_PRECISION (type) == TYPE_PRECISION (node))
3111 #if HOST_BITS_PER_WIDE_INT >= 64
3114 #endif
3123 #undef TYPE_OK
3126 }
3128 /* Build a bit-field integer type for the given WIDTH and UNSIGNEDP. */
3130 tree
3132 {
3133 /* Extended integer types of the same width as a standard type have
3134 lesser rank, so those of the same width as int promote to int or
3135 unsigned int and are valid for printf formats expecting int or
3136 unsigned int. To avoid such special cases, avoid creating
3137 extended integer types for bit-fields if a standard integer type
3138 is available. */
3155 }
3157 /* The C version of the register_builtin_type langhook. */
3159 void
3161 {
3162 tree decl;
3172 }
3173 \f
3174 /* Print an error message for invalid operands to arith operation
3175 CODE with TYPE0 for operand 0, and TYPE1 for operand 1.
3176 LOCATION is the location of the message. */
3178 void
3181 {
3185 {
3230 }
3234 }
3235 \f
3236 /* Subroutine of build_binary_op, used for comparison operations.
3237 See if the operands have both been converted from subword integer types
3238 and, if so, perhaps change them both back to their original type.
3239 This function is also responsible for converting the two operands
3240 to the proper common type for comparison.
3242 The arguments of this function are all pointers to local variables
3243 of build_binary_op: OP0_PTR is &OP0, OP1_PTR is &OP1,
3244 RESTYPE_PTR is &RESULT_TYPE and RESCODE_PTR is &RESULTCODE.
3246 If this function returns nonzero, it means that the comparison has
3247 a constant value. What this function returns is an expression for
3248 that value. */
3250 tree
3253 {
3254 tree type;
3262 /* Throw away any conversions to wider types
3263 already present in the operands. */
3268 /* Handle the case that OP0 does not *contain* a conversion
3269 but it *requires* conversion to FINAL_TYPE. */
3276 /* If one of the operands must be floated, we cannot optimize. */
3280 /* If first arg is constant, swap the args (changing operation
3281 so value is preserved), for canonicalization. Don't do this if
3282 the second arg is 0. */
3287 {
3304 {
3319 }
3321 }
3323 /* If comparing an integer against a constant more bits wide,
3324 maybe we can deduce a value of 1 or 0 independent of the data.
3325 Or else truncate the constant now
3326 rather than extend the variable at run time.
3328 This is only interesting if the constant is the wider arg.
3329 Also, it is not safe if the constant is unsigned and the
3330 variable arg is signed, since in this case the variable
3331 would be sign-extended and then regarded as unsigned.
3332 Our technique fails in this case because the lowest/highest
3333 possible unsigned results don't follow naturally from the
3334 lowest/highest possible values of the variable operand.
3335 For just EQ_EXPR and NE_EXPR there is another technique that
3336 could be used: see if the constant can be faithfully represented
3337 in the other operand's type, by truncating it and reextending it
3338 and see if that preserves the constant's value. */
3344 {
3347 /* 1 if comparison is nominally unsigned. */
3349 tree val;
3361 {
3362 /* Convert primop1 to target type, but do not introduce
3363 additional overflow. We know primop1 is an int_cst. */
3367 }
3369 {
3372 }
3375 {
3380 }
3381 else
3382 {
3387 }
3390 /* This used to be a switch, but Genix compiler can't handle that. */
3392 {
3395 }
3397 {
3400 }
3402 {
3407 }
3409 {
3414 }
3416 {
3421 }
3423 {
3428 }
3430 /* If primop0 was sign-extended and unsigned comparison specd,
3431 we did a signed comparison above using the signed type bounds.
3432 But the comparison we output must be unsigned.
3434 Also, for inequalities, VAL is no good; but if the signed
3435 comparison had *any* fixed result, it follows that the
3436 unsigned comparison just tests the sign in reverse
3437 (positive values are LE, negative ones GE).
3438 So we can generate an unsigned comparison
3439 against an extreme value of the signed type. */
3442 {
3445 {
3460 }
3462 }
3465 {
3470 }
3473 {
3474 /* Don't forget to evaluate PRIMOP0 if it has side effects. */
3478 }
3480 /* Value is not predetermined, but do the comparison
3481 in the type of the operand that is not constant.
3482 TYPE is already properly set. */
3483 }
3485 /* If either arg is decimal float and the other is float, find the
3486 proper common type to use for comparison. */
3497 /* If args' natural types are both narrower than nominal type
3498 and both extend in the same manner, compare them
3499 in the type of the wider arg.
3500 Otherwise must actually extend both to the nominal
3501 common type lest different ways of extending
3502 alter the result.
3503 (eg, (short)-1 == (unsigned short)-1 should be 0.) */
3508 {
3512 type);
3513 /* Make sure shorter operand is extended the right way
3514 to match the longer operand. */
3515 primop0
3518 primop0);
3519 primop1
3522 primop1);
3523 }
3524 else
3525 {
3526 /* Here we must do the comparison on the nominal type
3527 using the args exactly as we received them. */
3534 {
3537 {
3539 /* All unsigned values are >= 0, so we warn. However,
3540 if OP0 is a constant that is >= 0, the signedness of
3541 the comparison isn't an issue, so suppress the
3542 warning. */
3546 primop0))))
3556 primop0))))
3564 }
3567 {
3568 /* Don't forget to evaluate PRIMOP0 if it has side effects. */
3573 }
3574 }
3575 }
3583 }
3584 \f
3585 /* Return a tree for the sum or difference (RESULTCODE says which)
3586 of pointer PTROP and integer INTOP. */
3588 tree
3591 {
3594 /* The result is a pointer of the same type that is being added. */
3598 {
3602 }
3604 {
3608 }
3610 {
3614 }
3615 else
3618 /* We are manipulating pointer values, so we don't need to warn
3619 about relying on undefined signed overflow. We disable the
3620 warning here because we use integer types so fold won't know that
3621 they are really pointers. */
3624 /* If what we are about to multiply by the size of the elements
3625 contains a constant term, apply distributive law
3626 and multiply that constant term separately.
3627 This helps produce common subexpressions. */
3632 /* If the constant comes from pointer subtraction,
3633 skip this optimization--it would cause an error. */
3635 /* If the constant is unsigned, and smaller than the pointer size,
3636 then we must skip this optimization. This is because it could cause
3637 an overflow error if the constant is negative but INTOP is not. */
3641 {
3646 /* Convert both subexpression types to the type of intop,
3647 because weird cases involving pointer arithmetic
3648 can result in a sum or difference with different type args. */
3653 }
3655 /* Convert the integer argument to a type the same size as sizetype
3656 so the multiply won't overflow spuriously. */
3662 /* Replace the integer argument with a suitable product by the object size.
3663 Do this multiplication as signed, then convert to the appropriate type
3664 for the pointer operation and disregard an overflow that occured only
3665 because of the sign-extension change in the latter conversion. */
3666 {
3674 }
3676 /* Create the sum or difference. */
3685 }
3686 \f
3687 /* Wrap a C_MAYBE_CONST_EXPR around an expression that is fully folded
3688 and if NON_CONST is known not to be permitted in an evaluated part
3689 of a constant expression. */
3691 tree
3693 {
3697 /* This should never be called for C++. */
3701 /* The result of folding may have a NOP_EXPR to set TREE_NO_WARNING. */
3710 }
3712 /* Wrap a SAVE_EXPR around EXPR, if appropriate. Like save_expr, but
3713 for C folds the inside expression and wraps a C_MAYBE_CONST_EXPR
3714 around the SAVE_EXPR if needed so that c_fully_fold does not need
3715 to look inside SAVE_EXPRs. */
3717 tree
3719 {
3728 }
3730 /* Return whether EXPR is a declaration whose address can never be
3731 NULL. */
3733 bool
3735 {
3740 }
3742 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
3743 or for an `if' or `while' statement or ?..: exp. It should already
3744 have been validated to be of suitable type; otherwise, a bad
3745 diagnostic may result.
3747 The EXPR is located at LOCATION.
3749 This preparation consists of taking the ordinary
3750 representation of an expression expr and producing a valid tree
3751 boolean expression describing whether expr is nonzero. We could
3752 simply always do build_binary_op (NE_EXPR, expr, truthvalue_false_node, 1),
3753 but we optimize comparisons, &&, ||, and !.
3755 The resulting type should always be `truthvalue_type_node'. */
3757 tree
3759 {
3761 {
3803 ? truthvalue_true_node
3809 ? truthvalue_true_node
3814 /* Fall through. */
3817 {
3820 {
3821 /* Common Ada/Pascal programmer's mistake. */
3823 OPT_Waddress,
3825 inner);
3827 }
3829 }
3846 /* These don't change whether an object is nonzero or zero. */
3851 /* These don't change whether an object is zero or nonzero, but
3852 we can't ignore them if their second arg has side-effects. */
3854 {
3857 c_common_truthvalue_conversion
3860 }
3861 else
3866 /* Distribute the conversion into the arms of a COND_EXPR. */
3868 {
3878 }
3879 else
3880 {
3881 /* Folding will happen later for C. */
3889 }
3891 CASE_CONVERT:
3892 /* Don't cancel the effect of a CONVERT_EXPR from a REFERENCE_TYPE,
3893 since that affects how `default_conversion' will behave. */
3897 /* If this is widening the argument, we can ignore it. */
3907 {
3911 }
3916 }
3919 {
3921 expr = (build_binary_op
3925 c_common_truthvalue_conversion
3928 c_common_truthvalue_conversion
3933 }
3936 {
3941 }
3942 else
3945 ret:
3948 }
3949 \f
3958 /* Apply the TYPE_QUALS to the new DECL. */
3960 void
3962 {
3970 /* An object declared 'const' is only readonly after it is
3971 initialized. We don't have any way of expressing this currently,
3972 so we need to be conservative and unset TREE_READONLY for types
3973 with constructors. Otherwise aliasing code will ignore stores in
3974 an inline constructor. */
3978 {
3981 }
3983 {
3985 /* Allow 'restrict' on arrays of pointers.
3986 FIXME currently we just ignore it. */
3992 }
3993 }
3995 /* Hash function for the problem of multiple type definitions in
3996 different files. This must hash all types that will compare
3997 equal via comptypes to the same value. In practice it hashes
3998 on some of the simple stuff and leaves the details to comptypes. */
4000 static hashval_t
4002 {
4006 tree t2;
4008 {
4009 /* For pointers, hash on pointee type plus some swizzling. */
4012 /* Hash on number of elements and total size. */
4031 }
4033 i++;
4034 /* We might have a VLA here. */
4037 else
4040 }
4044 /* Return the typed-based alias set for T, which may be an expression
4045 or a type. Return -1 if we don't do anything special. */
4047 alias_set_type
4049 {
4050 tree u;
4053 /* For VLAs, use the alias set of the element type rather than the
4054 default of alias set 0 for types compared structurally. */
4056 {
4060 }
4062 /* Permit type-punning when accessing a union, provided the access
4063 is directly through the union. For example, this code does not
4064 permit taking the address of a union member and then storing
4065 through it. Even the type-punning allowed here is a GCC
4066 extension, albeit a common and useful one; the C standard says
4067 that such accesses have implementation-defined behavior. */
4075 /* That's all the expressions we handle specially. */
4079 /* The C standard guarantees that any object may be accessed via an
4080 lvalue that has character type. */
4086 /* The C standard specifically allows aliasing between signed and
4087 unsigned variants of the same type. We treat the signed
4088 variant as canonical. */
4090 {
4093 /* t1 == t can happen for boolean nodes which are always unsigned. */
4096 }
4098 /* Handle the case of multiple type nodes referring to "the same" type,
4099 which occurs with IMA. These share an alias set. FIXME: Currently only
4100 C90 is handled. (In C99 type compatibility is not transitive, which
4101 complicates things mightily. The alias set splay trees can theoretically
4102 represent this, but insertion is tricky when you consider all the
4103 different orders things might arrive in.) */
4108 /* Save time if there's only one input file. */
4112 /* Pointers need special handling if they point to any type that
4113 needs special handling (below). */
4115 {
4116 tree t2;
4117 /* Find bottom type under any nested POINTERs. */
4121 ;
4129 }
4130 /* These are the only cases that need special handling. */
4137 /* Undefined? */
4141 /* Look up t in hash table. Only one of the compatible types within each
4142 alias set is recorded in the table. */
4146 NULL);
4149 {
4152 }
4153 else
4154 /* Our caller will assign and record (in t) a new alias set; all we need
4155 to do is remember t in the hash table. */
4159 }
4160 \f
4161 /* Compute the value of 'sizeof (TYPE)' or '__alignof__ (TYPE)', where
4162 the second parameter indicates which OPERATOR is being applied.
4163 The COMPLAIN flag controls whether we should diagnose possibly
4164 ill-formed constructs or not. LOC is the location of the SIZEOF or
4165 TYPEOF operator. */
4167 tree
4170 {
4178 {
4180 {
4187 }
4188 else
4190 }
4192 {
4200 }
4202 {
4207 }
4208 else
4209 {
4211 /* Convert in case a char is more than one unit. */
4215 else
4217 }
4219 /* VALUE will have an integer type with TYPE_IS_SIZETYPE set.
4220 TYPE_IS_SIZETYPE means that certain things (like overflow) will
4221 never happen. However, this node should really have type
4222 `size_t', which is just a typedef for an ordinary integer type. */
4227 }
4229 /* Implement the __alignof keyword: Return the minimum required
4230 alignment of EXPR, measured in bytes. For VAR_DECLs,
4231 FUNCTION_DECLs and FIELD_DECLs return DECL_ALIGN (which can be set
4232 from an "aligned" __attribute__ specification). LOC is the
4233 location of the ALIGNOF operator. */
4235 tree
4237 {
4238 tree t;
4245 {
4248 }
4254 {
4261 {
4268 }
4270 }
4271 else
4275 }
4276 \f
4277 /* Handle C and C++ default attributes. */
4279 enum built_in_attribute
4280 {
4281 #define DEF_ATTR_NULL_TREE(ENUM) ENUM,
4282 #define DEF_ATTR_INT(ENUM, VALUE) ENUM,
4283 #define DEF_ATTR_IDENT(ENUM, STRING) ENUM,
4284 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) ENUM,
4286 #undef DEF_ATTR_NULL_TREE
4287 #undef DEF_ATTR_INT
4288 #undef DEF_ATTR_IDENT
4289 #undef DEF_ATTR_TREE_LIST
4290 ATTR_LAST
4291 };
4297 enum c_builtin_type
4298 {
4299 #define DEF_PRIMITIVE_TYPE(NAME, VALUE) NAME,
4300 #define DEF_FUNCTION_TYPE_0(NAME, RETURN) NAME,
4301 #define DEF_FUNCTION_TYPE_1(NAME, RETURN, ARG1) NAME,
4302 #define DEF_FUNCTION_TYPE_2(NAME, RETURN, ARG1, ARG2) NAME,
4303 #define DEF_FUNCTION_TYPE_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
4304 #define DEF_FUNCTION_TYPE_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
4305 #define DEF_FUNCTION_TYPE_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) NAME,
4306 #define DEF_FUNCTION_TYPE_6(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6) NAME,
4307 #define DEF_FUNCTION_TYPE_7(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7) NAME,
4308 #define DEF_FUNCTION_TYPE_VAR_0(NAME, RETURN) NAME,
4309 #define DEF_FUNCTION_TYPE_VAR_1(NAME, RETURN, ARG1) NAME,
4310 #define DEF_FUNCTION_TYPE_VAR_2(NAME, RETURN, ARG1, ARG2) NAME,
4311 #define DEF_FUNCTION_TYPE_VAR_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
4312 #define DEF_FUNCTION_TYPE_VAR_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
4313 #define DEF_FUNCTION_TYPE_VAR_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG6) \
4314 NAME,
4315 #define DEF_POINTER_TYPE(NAME, TYPE) NAME,
4317 #undef DEF_PRIMITIVE_TYPE
4318 #undef DEF_FUNCTION_TYPE_0
4319 #undef DEF_FUNCTION_TYPE_1
4320 #undef DEF_FUNCTION_TYPE_2
4321 #undef DEF_FUNCTION_TYPE_3
4322 #undef DEF_FUNCTION_TYPE_4
4323 #undef DEF_FUNCTION_TYPE_5
4324 #undef DEF_FUNCTION_TYPE_6
4325 #undef DEF_FUNCTION_TYPE_7
4326 #undef DEF_FUNCTION_TYPE_VAR_0
4327 #undef DEF_FUNCTION_TYPE_VAR_1
4328 #undef DEF_FUNCTION_TYPE_VAR_2
4329 #undef DEF_FUNCTION_TYPE_VAR_3
4330 #undef DEF_FUNCTION_TYPE_VAR_4
4331 #undef DEF_FUNCTION_TYPE_VAR_5
4332 #undef DEF_POINTER_TYPE
4333 BT_LAST
4334 };
4338 /* A temporary array for c_common_nodes_and_builtins. Used in
4339 communication with def_fn_type. */
4342 /* A helper function for c_common_nodes_and_builtins. Build function type
4343 for DEF with return type RET and N arguments. If VAR is true, then the
4344 function should be variadic after those N arguments.
4346 Takes special care not to ICE if any of the types involved are
4347 error_mark_node, which indicates that said type is not in fact available
4348 (see builtin_type_for_size). In which case the function type as a whole
4349 should be error_mark_node. */
4351 static void
4353 {
4360 {
4366 }
4378 egress:
4380 }
4382 /* Build builtin functions common to both C and C++ language
4383 frontends. */
4385 static void
4387 {
4388 #define DEF_PRIMITIVE_TYPE(ENUM, VALUE) \
4389 builtin_types[ENUM] = VALUE;
4390 #define DEF_FUNCTION_TYPE_0(ENUM, RETURN) \
4391 def_fn_type (ENUM, RETURN, 0, 0);
4392 #define DEF_FUNCTION_TYPE_1(ENUM, RETURN, ARG1) \
4393 def_fn_type (ENUM, RETURN, 0, 1, ARG1);
4394 #define DEF_FUNCTION_TYPE_2(ENUM, RETURN, ARG1, ARG2) \
4395 def_fn_type (ENUM, RETURN, 0, 2, ARG1, ARG2);
4396 #define DEF_FUNCTION_TYPE_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
4397 def_fn_type (ENUM, RETURN, 0, 3, ARG1, ARG2, ARG3);
4398 #define DEF_FUNCTION_TYPE_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
4399 def_fn_type (ENUM, RETURN, 0, 4, ARG1, ARG2, ARG3, ARG4);
4400 #define DEF_FUNCTION_TYPE_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
4401 def_fn_type (ENUM, RETURN, 0, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
4402 #define DEF_FUNCTION_TYPE_6(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
4403 ARG6) \
4404 def_fn_type (ENUM, RETURN, 0, 6, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6);
4405 #define DEF_FUNCTION_TYPE_7(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
4406 ARG6, ARG7) \
4407 def_fn_type (ENUM, RETURN, 0, 7, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7);
4408 #define DEF_FUNCTION_TYPE_VAR_0(ENUM, RETURN) \
4409 def_fn_type (ENUM, RETURN, 1, 0);
4410 #define DEF_FUNCTION_TYPE_VAR_1(ENUM, RETURN, ARG1) \
4411 def_fn_type (ENUM, RETURN, 1, 1, ARG1);
4412 #define DEF_FUNCTION_TYPE_VAR_2(ENUM, RETURN, ARG1, ARG2) \
4413 def_fn_type (ENUM, RETURN, 1, 2, ARG1, ARG2);
4414 #define DEF_FUNCTION_TYPE_VAR_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
4415 def_fn_type (ENUM, RETURN, 1, 3, ARG1, ARG2, ARG3);
4416 #define DEF_FUNCTION_TYPE_VAR_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
4417 def_fn_type (ENUM, RETURN, 1, 4, ARG1, ARG2, ARG3, ARG4);
4418 #define DEF_FUNCTION_TYPE_VAR_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
4419 def_fn_type (ENUM, RETURN, 1, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
4420 #define DEF_POINTER_TYPE(ENUM, TYPE) \
4421 builtin_types[(int) ENUM] = build_pointer_type (builtin_types[(int) TYPE]);
4425 #undef DEF_PRIMITIVE_TYPE
4426 #undef DEF_FUNCTION_TYPE_1
4427 #undef DEF_FUNCTION_TYPE_2
4428 #undef DEF_FUNCTION_TYPE_3
4429 #undef DEF_FUNCTION_TYPE_4
4430 #undef DEF_FUNCTION_TYPE_5
4431 #undef DEF_FUNCTION_TYPE_6
4432 #undef DEF_FUNCTION_TYPE_VAR_0
4433 #undef DEF_FUNCTION_TYPE_VAR_1
4434 #undef DEF_FUNCTION_TYPE_VAR_2
4435 #undef DEF_FUNCTION_TYPE_VAR_3
4436 #undef DEF_FUNCTION_TYPE_VAR_4
4437 #undef DEF_FUNCTION_TYPE_VAR_5
4438 #undef DEF_POINTER_TYPE
4443 #define DEF_BUILTIN(ENUM, NAME, CLASS, TYPE, LIBTYPE, BOTH_P, FALLBACK_P, \
4444 NONANSI_P, ATTRS, IMPLICIT, COND) \
4445 if (NAME && COND) \
4446 def_builtin_1 (ENUM, NAME, CLASS, \
4447 builtin_types[(int) TYPE], \
4448 builtin_types[(int) LIBTYPE], \
4449 BOTH_P, FALLBACK_P, NONANSI_P, \
4450 built_in_attributes[(int) ATTRS], IMPLICIT);
4452 #undef DEF_BUILTIN
4460 }
4462 /* Like get_identifier, but avoid warnings about null arguments when
4463 the argument may be NULL for targets where GCC lacks stdint.h type
4464 information. */
4468 {
4470 }
4472 /* Build tree nodes and builtin functions common to both C and C++ language
4473 frontends. */
4475 void
4477 {
4481 tree array_domain_type;
4482 tree va_list_ref_type_node;
4483 tree va_list_arg_type_node;
4485 /* Define `int' and `char' first so that dbx will output them first. */
4489 /* `signed' is the same as `int'. FIXME: the declarations of "signed",
4490 "unsigned long", "long long unsigned" and "unsigned short" were in C++
4491 but not C. Are the conditionals here needed? */
4497 long_unsigned_type_node);
4499 {
4501 int128_integer_type_node);
4503 int128_unsigned_type_node);
4504 }
4508 long_long_integer_type_node);
4510 long_long_unsigned_type_node);
4513 long_long_unsigned_type_node);
4516 short_unsigned_type_node);
4519 short_unsigned_type_node);
4521 /* Define both `signed char' and `unsigned char'. */
4525 /* These are types that c_common_type_for_size and
4526 c_common_type_for_mode use. */
4529 intQI_type_node));
4532 intHI_type_node));
4535 intSI_type_node));
4538 intDI_type_node));
4539 #if HOST_BITS_PER_WIDE_INT >= 64
4542 TYPE_DECL,
4544 intTI_type_node));
4545 #endif
4548 unsigned_intQI_type_node));
4551 unsigned_intHI_type_node));
4554 unsigned_intSI_type_node));
4557 unsigned_intDI_type_node));
4558 #if HOST_BITS_PER_WIDE_INT >= 64
4561 TYPE_DECL,
4563 unsigned_intTI_type_node));
4564 #endif
4566 /* Create the widest literal types. */
4567 widest_integer_literal_type_node
4571 widest_integer_literal_type_node));
4573 widest_unsigned_literal_type_node
4577 widest_unsigned_literal_type_node));
4579 /* `unsigned long' is the standard type for sizeof.
4580 Note that stddef.h uses `unsigned long',
4581 and this must agree, even if long and int are the same size. */
4582 size_type_node =
4587 pid_type_node =
4596 /* Only supported decimal floating point extension if the target
4597 actually supports underlying modes. */
4601 {
4605 }
4608 {
4613 long_long_fract_type_node);
4615 unsigned_short_fract_type_node);
4617 unsigned_fract_type_node);
4619 unsigned_long_fract_type_node);
4621 unsigned_long_long_fract_type_node);
4623 sat_short_fract_type_node);
4626 sat_long_fract_type_node);
4628 sat_long_long_fract_type_node);
4630 sat_unsigned_short_fract_type_node);
4632 sat_unsigned_fract_type_node);
4634 sat_unsigned_long_fract_type_node);
4636 sat_unsigned_long_long_fract_type_node);
4641 long_long_accum_type_node);
4643 unsigned_short_accum_type_node);
4645 unsigned_accum_type_node);
4647 unsigned_long_accum_type_node);
4649 unsigned_long_long_accum_type_node);
4651 sat_short_accum_type_node);
4654 sat_long_accum_type_node);
4656 sat_long_long_accum_type_node);
4658 sat_unsigned_short_accum_type_node);
4660 sat_unsigned_accum_type_node);
4662 sat_unsigned_long_accum_type_node);
4664 sat_unsigned_long_long_accum_type_node);
4666 }
4669 TYPE_DECL,
4671 complex_integer_type_node));
4673 TYPE_DECL,
4675 complex_float_type_node));
4677 TYPE_DECL,
4679 complex_double_type_node));
4683 complex_long_double_type_node));
4686 /* For C++, make fileptr_type_node a distinct void * type until
4687 FILE type is defined. */
4692 /* Set the TYPE_NAME for any variants that were built before
4693 record_builtin_type gave names to the built-in types. */
4694 {
4700 }
4702 /* This node must not be shared. */
4708 /* Make a type to be the domain of a few array types
4709 whose domains don't really matter.
4710 200 is small enough that it always fits in size_t
4711 and large enough that it can hold most function names for the
4712 initializations of __FUNCTION__ and __PRETTY_FUNCTION__. */
4715 /* Make a type for arrays of characters.
4716 With luck nothing will ever really depend on the length of this
4717 array type. */
4718 char_array_type_node
4721 /* Likewise for arrays of ints. */
4722 int_array_type_node
4726 const_string_type_node
4730 /* This is special for C++ so functions can be overloaded. */
4736 {
4739 else
4742 }
4744 /* This is for wide string constants. */
4745 wchar_array_type_node
4748 /* Define 'char16_t'. */
4753 {
4758 }
4760 /* This is for UTF-16 string constants. */
4761 char16_array_type_node
4764 /* Define 'char32_t'. */
4769 {
4774 }
4776 /* This is for UTF-32 string constants. */
4777 char32_array_type_node
4780 wint_type_node =
4783 intmax_type_node =
4785 uintmax_type_node =
4789 sig_atomic_type_node =
4792 int8_type_node =
4795 int16_type_node =
4798 int32_type_node =
4801 int64_type_node =
4804 uint8_type_node =
4807 uint16_type_node =
4810 c_uint32_type_node =
4813 c_uint64_type_node =
4816 int_least8_type_node =
4819 int_least16_type_node =
4822 int_least32_type_node =
4825 int_least64_type_node =
4828 uint_least8_type_node =
4831 uint_least16_type_node =
4834 uint_least32_type_node =
4837 uint_least64_type_node =
4840 int_fast8_type_node =
4843 int_fast16_type_node =
4846 int_fast32_type_node =
4849 int_fast64_type_node =
4852 uint_fast8_type_node =
4855 uint_fast16_type_node =
4858 uint_fast32_type_node =
4861 uint_fast64_type_node =
4864 intptr_type_node =
4867 uintptr_type_node =
4871 ptrdiff_type_node
4878 va_list_type_node));
4880 {
4883 tree ptype;
4886 {
4890 ptype));
4892 }
4893 }
4896 {
4899 }
4900 else
4901 {
4904 }
4911 /* Create the built-in __null node. It is important that this is
4912 not shared. */
4916 /* Since builtin_types isn't gc'ed, don't export these nodes. */
4918 }
4920 /* The number of named compound-literals generated thus far. */
4923 /* Set DECL_NAME for DECL, a VAR_DECL for a compound-literal. */
4925 void
4927 {
4930 compound_literal_number);
4931 compound_literal_number++;
4933 }
4935 tree
4937 {
4941 }
4944 /* Linked list of disabled built-in functions. */
4947 {
4955 /* Disable a built-in function specified by -fno-builtin-NAME. If NAME
4956 begins with "__builtin_", give an error. */
4958 void
4960 {
4963 else
4964 {
4969 }
4970 }
4973 /* Return true if the built-in function NAME has been disabled, false
4974 otherwise. */
4976 static bool
4978 {
4981 {
4984 }
4986 }
4989 /* Worker for DEF_BUILTIN.
4990 Possibly define a builtin function with one or two names.
4991 Does not declare a non-__builtin_ function if flag_no_builtin, or if
4992 nonansi_p and flag_no_nonansi_builtin. */
4994 static void
5001 {
5002 tree decl;
5015 fnattrs);
5025 }
5026 \f
5027 /* Nonzero if the type T promotes to int. This is (nearly) the
5028 integral promotions defined in ISO C99 6.3.1.1/2. */
5030 bool
5032 {
5034 {
5044 /* ??? Technically all enumerations not larger than an int
5045 promote to an int. But this is used along code paths
5046 that only want to notice a size change. */
5054 }
5055 }
5057 /* Return 1 if PARMS specifies a fixed number of parameters
5058 and none of their types is affected by default promotions. */
5060 int
5062 {
5063 const_tree t;
5065 {
5082 }
5084 }
5086 /* Recursively remove any '*' or '&' operator from TYPE. */
5087 tree
5089 {
5093 }
5095 /* Recursively remove pointer or array type from TYPE. */
5096 tree
5098 {
5102 }
5104 /* Used to compare case labels. K1 and K2 are actually tree nodes
5105 representing case labels, or NULL_TREE for a `default' label.
5106 Returns -1 if K1 is ordered before K2, -1 if K1 is ordered after
5107 K2, and 0 if K1 and K2 are equal. */
5109 int
5111 {
5112 /* Consider a NULL key (such as arises with a `default' label) to be
5113 smaller than anything else. */
5120 }
5122 /* Process a case label, located at LOC, for the range LOW_VALUE
5123 ... HIGH_VALUE. If LOW_VALUE and HIGH_VALUE are both NULL_TREE
5124 then this case label is actually a `default' label. If only
5125 HIGH_VALUE is NULL_TREE, then case label was declared using the
5126 usual C/C++ syntax, rather than the GNU case range extension.
5127 CASES is a tree containing all the case ranges processed so far;
5128 COND is the condition for the switch-statement itself. Returns the
5129 CASE_LABEL_EXPR created, or ERROR_MARK_NODE if no CASE_LABEL_EXPR
5130 is created. */
5132 tree
5135 {
5136 tree type;
5137 tree label;
5138 tree case_label;
5139 splay_tree_node node;
5141 /* Create the LABEL_DECL itself. */
5144 /* If there was an error processing the switch condition, bail now
5145 before we get more confused. */
5153 {
5156 }
5158 /* Case ranges are a GNU extension. */
5165 {
5170 }
5172 {
5177 }
5180 {
5181 /* If the LOW_VALUE and HIGH_VALUE are the same, then this isn't
5182 really a case range, even though it was written that way.
5183 Remove the HIGH_VALUE to simplify later processing. */
5188 }
5190 /* See if the case is in range of the type of the original testing
5191 expression. If both low_value and high_value are out of range,
5192 don't insert the case label and return NULL_TREE. */
5198 /* Look up the LOW_VALUE in the table of case labels we already
5199 have. */
5201 /* If there was not an exact match, check for overlapping ranges.
5202 There's no need to do this if there's no LOW_VALUE or HIGH_VALUE;
5203 that's a `default' label and the only overlap is an exact match. */
5205 {
5206 splay_tree_node low_bound;
5207 splay_tree_node high_bound;
5209 /* Even though there wasn't an exact match, there might be an
5210 overlap between this case range and another case range.
5211 Since we've (inductively) not allowed any overlapping case
5212 ranges, we simply need to find the greatest low case label
5213 that is smaller that LOW_VALUE, and the smallest low case
5214 label that is greater than LOW_VALUE. If there is an overlap
5215 it will occur in one of these two ranges. */
5221 /* Check to see if the LOW_BOUND overlaps. It is smaller than
5222 the LOW_VALUE, so there is no need to check unless the
5223 LOW_BOUND is in fact itself a case range. */
5229 /* Check to see if the HIGH_BOUND overlaps. The low end of that
5230 range is bigger than the low end of the current range, so we
5231 are only interested if the current range is a real range, and
5232 not an ordinary case label. */
5234 && high_value
5236 high_value)
5239 }
5240 /* If there was an overlap, issue an error. */
5242 {
5246 {
5250 }
5252 {
5255 }
5256 else
5257 {
5261 }
5263 }
5265 /* Add a CASE_LABEL to the statement-tree. */
5267 /* Register this case label in the splay tree. */
5274 error_out:
5275 /* Add a label so that the back-end doesn't think that the beginning of
5276 the switch is unreachable. Note that we do not add a case label, as
5277 that just leads to duplicates and thence to failure later on. */
5279 {
5282 }
5284 }
5286 /* Subroutines of c_do_switch_warnings, called via splay_tree_foreach.
5287 Used to verify that case values match up with enumerator values. */
5289 static void
5291 {
5294 /* ??? Not working too hard to print the double-word value.
5295 Should perhaps be done with %lwd in the diagnostic routines? */
5304 else
5313 buf);
5314 else
5319 }
5321 /* Subroutine of c_do_switch_warnings, called via splay_tree_foreach.
5322 Used to verify that case values match up with enumerator values. */
5324 static int
5326 {
5330 /* Skip default case. */
5334 /* If CASE_LOW_SEEN is not set, that means CASE_LOW did not appear
5335 when we did our enum->case scan. Reset our scratch bit after. */
5338 else
5341 /* If CASE_HIGH is non-null, we have a range. If CASE_HIGH_SEEN is
5342 not set, that means that CASE_HIGH did not appear when we did our
5343 enum->case scan. Reset our scratch bit after. */
5345 {
5348 else
5350 }
5353 }
5355 /* Handle -Wswitch*. Called from the front end after parsing the
5356 switch construct. */
5357 /* ??? Should probably be somewhere generic, since other languages
5358 besides C and C++ would want this. At the moment, however, C/C++
5359 are the only tree-ssa languages that support enumerations at all,
5360 so the point is moot. */
5362 void
5365 {
5366 splay_tree_node default_node;
5367 splay_tree_node node;
5368 tree chain;
5378 /* From here on, we only care about about enumerated types. */
5382 /* From here on, we only care about -Wswitch and -Wswitch-enum. */
5386 /* Check the cases. Warn about case values which are not members of
5387 the enumerated type. For -Wswitch-enum, or for -Wswitch when
5388 there is no default case, check that exactly all enumeration
5389 literals are covered by the cases. */
5391 /* Clearing COND if it is not an integer constant simplifies
5392 the tests inside the loop below. */
5396 /* The time complexity here is O(N*lg(N)) worst case, but for the
5397 common case of monotonically increasing enumerators, it is
5398 O(N), since the nature of the splay tree will keep the next
5399 element adjacent to the root at all times. */
5402 {
5408 {
5409 /* Mark the CASE_LOW part of the case entry as seen. */
5413 }
5415 /* Even though there wasn't an exact match, there might be a
5416 case range which includes the enumerator's value. */
5419 {
5423 {
5424 /* If we match the upper bound exactly, mark the CASE_HIGH
5425 part of the case entry as seen. */
5429 }
5430 }
5432 /* We've now determined that this enumerated literal isn't
5433 handled by the case labels of the switch statement. */
5435 /* If the switch expression is a constant, we only really care
5436 about whether that constant is handled by the switch. */
5440 /* If there is a default_node, the only relevant option is
5441 Wswitch-enum. Otherwise, if both are enabled then we prefer
5442 to warn using -Wswitch because -Wswitch is enabled by -Wall
5443 while -Wswitch-enum is explicit. */
5446 ? OPT_Wswitch_enum
5450 }
5452 /* Warn if there are case expressions that don't correspond to
5453 enumerators. This can occur since C and C++ don't enforce
5454 type-checking of assignments to enumeration variables.
5456 The time complexity here is now always O(N) worst case, since
5457 we should have marked both the lower bound and upper bound of
5458 every disjoint case label, with CASE_LOW_SEEN and CASE_HIGH_SEEN
5459 above. This scan also resets those fields. */
5462 }
5464 /* Finish an expression taking the address of LABEL (an
5465 IDENTIFIER_NODE). Returns an expression for the address.
5467 LOC is the location for the expression returned. */
5469 tree
5471 {
5472 tree result;
5482 else
5483 {
5486 /* The current function is not necessarily uninlinable.
5487 Computed gotos are incompatible with inlining, but the value
5488 here could be used only in a diagnostic, for example. */
5490 }
5493 }
5494 \f
5496 /* Given a boolean expression ARG, return a tree representing an increment
5497 or decrement (as indicated by CODE) of ARG. The front end must check for
5498 invalid cases (e.g., decrement in C++). */
5499 tree
5501 {
5502 tree val;
5507 {
5530 }
5533 }
5534 \f
5535 /* Built-in macros for stddef.h and stdint.h, that require macros
5536 defined in this file. */
5537 void
5539 {
5602 }
5604 static void
5606 {
5607 /* Fill in the built_in_attributes array. */
5608 #define DEF_ATTR_NULL_TREE(ENUM) \
5609 built_in_attributes[(int) ENUM] = NULL_TREE;
5610 #define DEF_ATTR_INT(ENUM, VALUE) \
5611 built_in_attributes[(int) ENUM] = build_int_cst (NULL_TREE, VALUE);
5612 #define DEF_ATTR_IDENT(ENUM, STRING) \
5613 built_in_attributes[(int) ENUM] = get_identifier (STRING);
5614 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) \
5615 built_in_attributes[(int) ENUM] \
5616 = tree_cons (built_in_attributes[(int) PURPOSE], \
5617 built_in_attributes[(int) VALUE], \
5618 built_in_attributes[(int) CHAIN]);
5620 #undef DEF_ATTR_NULL_TREE
5621 #undef DEF_ATTR_INT
5622 #undef DEF_ATTR_IDENT
5623 #undef DEF_ATTR_TREE_LIST
5624 }
5626 /* Returns TRUE iff the attribute indicated by ATTR_ID takes a plain
5627 identifier as an argument, so the front end shouldn't look it up. */
5629 bool
5631 {
5636 else
5638 }
5640 /* Attribute handlers common to C front ends. */
5642 /* Handle a "packed" attribute; arguments as in
5643 struct attribute_spec.handler. */
5645 static tree
5648 {
5650 {
5654 }
5656 {
5658 /* Still pack bitfields. */
5663 else
5665 }
5666 /* We can't set DECL_PACKED for a VAR_DECL, because the bit is
5667 used for DECL_REGISTER. It wouldn't mean anything anyway.
5668 We can't set DECL_PACKED on the type of a TYPE_DECL, because
5669 that changes what the typedef is typing. */
5670 else
5671 {
5674 }
5677 }
5679 /* Handle a "nocommon" attribute; arguments as in
5680 struct attribute_spec.handler. */
5682 static tree
5686 {
5689 else
5690 {
5693 }
5696 }
5698 /* Handle a "common" attribute; arguments as in
5699 struct attribute_spec.handler. */
5701 static tree
5704 {
5707 else
5708 {
5711 }
5714 }
5716 /* Handle a "noreturn" attribute; arguments as in
5717 struct attribute_spec.handler. */
5719 static tree
5722 {
5725 /* See FIXME comment in c_common_attribute_table. */
5731 = build_pointer_type
5734 else
5735 {
5738 }
5741 }
5743 /* Handle a "hot" and attribute; arguments as in
5744 struct attribute_spec.handler. */
5746 static tree
5749 {
5751 {
5753 {
5757 }
5758 /* Most of the rest of the hot processing is done later with
5759 lookup_attribute. */
5760 }
5761 else
5762 {
5765 }
5768 }
5769 /* Handle a "cold" and attribute; arguments as in
5770 struct attribute_spec.handler. */
5772 static tree
5775 {
5777 {
5779 {
5783 }
5784 /* Most of the rest of the cold processing is done later with
5785 lookup_attribute. */
5786 }
5787 else
5788 {
5791 }
5794 }
5796 /* Handle a "noinline" attribute; arguments as in
5797 struct attribute_spec.handler. */
5799 static tree
5803 {
5806 else
5807 {
5810 }
5813 }
5815 /* Handle a "noclone" attribute; arguments as in
5816 struct attribute_spec.handler. */
5818 static tree
5822 {
5824 {
5827 }
5830 }
5832 /* Handle a "always_inline" attribute; arguments as in
5833 struct attribute_spec.handler. */
5835 static tree
5840 {
5842 {
5843 /* Set the attribute and mark it for disregarding inline
5844 limits. */
5846 }
5847 else
5848 {
5851 }
5854 }
5856 /* Handle a "gnu_inline" attribute; arguments as in
5857 struct attribute_spec.handler. */
5859 static tree
5864 {
5866 {
5867 /* Do nothing else, just set the attribute. We'll get at
5868 it later with lookup_attribute. */
5869 }
5870 else
5871 {
5874 }
5877 }
5879 /* Handle an "artificial" attribute; arguments as in
5880 struct attribute_spec.handler. */
5882 static tree
5887 {
5889 {
5890 /* Do nothing else, just set the attribute. We'll get at
5891 it later with lookup_attribute. */
5892 }
5893 else
5894 {
5897 }
5900 }
5902 /* Handle a "flatten" attribute; arguments as in
5903 struct attribute_spec.handler. */
5905 static tree
5907 tree args ATTRIBUTE_UNUSED,
5909 {
5911 /* Do nothing else, just set the attribute. We'll get at
5912 it later with lookup_attribute. */
5913 ;
5914 else
5915 {
5918 }
5921 }
5923 /* Handle a "warning" or "error" attribute; arguments as in
5924 struct attribute_spec.handler. */
5926 static tree
5929 {
5932 /* Do nothing else, just set the attribute. We'll get at
5933 it later with lookup_attribute. */
5934 ;
5935 else
5936 {
5939 }
5942 }
5944 /* Handle a "used" attribute; arguments as in
5945 struct attribute_spec.handler. */
5947 static tree
5950 {
5955 {
5960 }
5961 else
5962 {
5965 }
5968 }
5970 /* Handle a "unused" attribute; arguments as in
5971 struct attribute_spec.handler. */
5973 static tree
5976 {
5978 {
5986 {
5991 }
5992 else
5993 {
5996 }
5997 }
5998 else
5999 {
6003 }
6006 }
6008 /* Handle a "externally_visible" attribute; arguments as in
6009 struct attribute_spec.handler. */
6011 static tree
6016 {
6020 {
6023 {
6027 }
6028 }
6029 else
6030 {
6033 }
6036 }
6038 /* Handle a "const" attribute; arguments as in
6039 struct attribute_spec.handler. */
6041 static tree
6044 {
6047 /* See FIXME comment on noreturn in c_common_attribute_table. */
6053 = build_pointer_type
6056 else
6057 {
6060 }
6063 }
6065 /* Handle a "transparent_union" attribute; arguments as in
6066 struct attribute_spec.handler. */
6068 static tree
6072 {
6073 tree type;
6082 {
6083 /* When IN_PLACE is set, leave the check for FIELDS and MODE to
6084 the code in finish_struct. */
6086 {
6091 /* A type variant isn't good enough, since we don't a cast
6092 to such a type removed as a no-op. */
6094 }
6098 }
6100 ignored:
6103 }
6105 /* Subroutine of handle_{con,de}structor_attribute. Evaluate ARGS to
6106 get the requested priority for a constructor or destructor,
6107 possibly issuing diagnostics for invalid or reserved
6108 priorities. */
6110 static priority_type
6112 {
6113 HOST_WIDE_INT pri;
6114 tree arg;
6120 {
6123 else
6126 }
6138 {
6141 "destructor priorities from 0 to %d are reserved "
6143 MAX_RESERVED_INIT_PRIORITY);
6144 else
6146 "constructor priorities from 0 to %d are reserved "
6148 MAX_RESERVED_INIT_PRIORITY);
6149 }
6152 invalid:
6155 MAX_INIT_PRIORITY);
6156 else
6158 MAX_INIT_PRIORITY);
6160 }
6162 /* Handle a "constructor" attribute; arguments as in
6163 struct attribute_spec.handler. */
6165 static tree
6169 {
6176 {
6177 priority_type priority;
6182 }
6183 else
6184 {
6187 }
6190 }
6192 /* Handle a "destructor" attribute; arguments as in
6193 struct attribute_spec.handler. */
6195 static tree
6199 {
6206 {
6207 priority_type priority;
6212 }
6213 else
6214 {
6217 }
6220 }
6222 /* Nonzero if the mode is a valid vector mode for this architecture.
6223 This returns nonzero even if there is no hardware support for the
6224 vector mode, but we can emulate with narrower modes. */
6226 static int
6228 {
6232 /* Doh! What's going on? */
6241 /* Hardware support. Woo hoo! */
6247 /* We should probably return 1 if requesting V4DI and we have no DI,
6248 but we have V2DI, but this is probably very unlikely. */
6250 /* If we have support for the inner mode, we can safely emulate it.
6251 We may not have V2DI, but me can emulate with a pair of DIs. */
6253 }
6256 /* Handle a "mode" attribute; arguments as in
6257 struct attribute_spec.handler. */
6259 static tree
6262 {
6270 else
6271 {
6276 tree typefm;
6281 {
6287 }
6289 /* Change this type to have a type with the specified mode.
6290 First check for the special modes. */
6303 else
6306 {
6309 }
6312 {
6315 }
6319 {
6351 }
6353 {
6356 }
6359 {
6364 {
6367 }
6371 else
6374 }
6375 else
6376 {
6377 /* For fixed-point modes, we need to test if the signness of type
6378 and the machine mode are consistent. */
6381 {
6384 }
6385 /* For fixed-point modes, we need to pass saturating info. */
6389 }
6392 {
6395 }
6397 {
6398 /* For enumeral types, copy the precision from the integer
6399 type returned above. If not an INTEGER_TYPE, we can't use
6400 this mode for this type. */
6402 {
6405 }
6408 {
6411 }
6412 else
6413 {
6414 /* We cannot build a type variant, as there's code that assumes
6415 that TYPE_MAIN_VARIANT has the same mode. This includes the
6416 debug generators. Instead, create a subrange type. This
6417 results in all of the enumeral values being emitted only once
6418 in the original, and the subtype gets them by reference. */
6421 else
6424 }
6425 }
6429 {
6432 }
6435 }
6438 }
6440 /* Handle a "section" attribute; arguments as in
6441 struct attribute_spec.handler. */
6443 static tree
6446 {
6450 {
6456 {
6460 {
6462 "section attribute cannot be specified for "
6465 }
6467 /* The decl may have already been given a section attribute
6468 from a previous declaration. Ensure they match. */
6472 {
6476 }
6480 {
6483 }
6484 else
6486 }
6487 else
6488 {
6491 }
6492 }
6493 else
6494 {
6498 }
6501 }
6503 /* Handle a "aligned" attribute; arguments as in
6504 struct attribute_spec.handler. */
6506 static tree
6509 {
6518 {
6522 }
6527 {
6530 }
6532 {
6535 }
6537 {
6540 }
6542 {
6545 /* If we have a TYPE_DECL, then copy the type, so that we
6546 don't accidentally modify a builtin type. See pushdecl. */
6549 {
6556 }
6557 else
6562 }
6565 {
6568 }
6571 {
6576 else
6580 }
6581 else
6582 {
6585 }
6588 }
6590 /* Handle a "weak" attribute; arguments as in
6591 struct attribute_spec.handler. */
6593 static tree
6598 {
6601 {
6604 }
6606 {
6610 }
6614 else
6618 }
6620 /* Handle an "alias" or "ifunc" attribute; arguments as in
6621 struct attribute_spec.handler, except that IS_ALIAS tells us
6622 whether this is an alias as opposed to ifunc attribute. */
6624 static tree
6627 {
6632 {
6635 }
6639 /* A static variable declaration is always a tentative definition,
6640 but the alias is a non-tentative definition which overrides. */
6643 {
6647 }
6651 {
6655 }
6657 /* Note that the very first time we process a nested declaration,
6658 decl_function_context will not be set. Indeed, *would* never
6659 be set except for the DECL_INITIAL/DECL_EXTERNAL frobbery that
6660 we do below. After such frobbery, pushdecl would set the context.
6661 In any case, this is never what we want. */
6663 {
6664 tree id;
6668 {
6672 }
6674 /* This counts as a use of the object pointed to. */
6679 else
6680 {
6683 else
6686 }
6689 /* ifuncs are also aliases, so set that attribute too. */
6692 }
6693 else
6694 {
6697 }
6700 }
6702 /* Handle an "alias" or "ifunc" attribute; arguments as in
6703 struct attribute_spec.handler. */
6705 static tree
6708 {
6710 }
6712 /* Handle an "alias" or "ifunc" attribute; arguments as in
6713 struct attribute_spec.handler. */
6715 static tree
6718 {
6720 }
6722 /* Handle a "weakref" attribute; arguments as in struct
6723 attribute_spec.handler. */
6725 static tree
6728 {
6731 /* We must ignore the attribute when it is associated with
6732 local-scoped decls, since attribute alias is ignored and many
6733 such symbols do not even have a DECL_WEAK field. */
6735 || current_function_decl
6737 {
6741 }
6744 {
6748 }
6750 /* The idea here is that `weakref("name")' mutates into `weakref,
6751 alias("name")', and weakref without arguments, in turn,
6752 implicitly adds weak. */
6755 {
6762 }
6763 else
6764 {
6769 /* Can't call declare_weak because it wants this to be TREE_PUBLIC,
6770 and that isn't supported; and because it wants to add it to
6771 the list of weak decls, which isn't helpful. */
6773 }
6776 }
6778 /* Handle an "visibility" attribute; arguments as in
6779 struct attribute_spec.handler. */
6781 static tree
6785 {
6791 {
6795 {
6797 name);
6799 }
6801 {
6805 }
6806 }
6808 {
6811 }
6814 {
6817 }
6819 /* If this is a type, set the visibility on the type decl. */
6821 {
6826 {
6828 name);
6830 }
6831 }
6841 else
6842 {
6843 error ("visibility argument must be one of \"default\", \"hidden\", \"protected\" or \"internal\"");
6845 }
6849 {
6863 }
6868 /* Go ahead and attach the attribute to the node as well. This is needed
6869 so we can determine whether we have VISIBILITY_DEFAULT because the
6870 visibility was not specified, or because it was explicitly overridden
6871 from the containing scope. */
6874 }
6876 /* Determine the ELF symbol visibility for DECL, which is either a
6877 variable or a function. It is an error to use this function if a
6878 definition of DECL is not available in this translation unit.
6879 Returns true if the final visibility has been determined by this
6880 function; false if the caller is free to make additional
6881 modifications. */
6883 bool
6885 {
6889 /* If the user explicitly specified the visibility with an
6890 attribute, honor that. DECL_VISIBILITY will have been set during
6891 the processing of the attribute. We check for an explicit
6892 attribute, rather than just checking DECL_VISIBILITY_SPECIFIED,
6893 to distinguish the use of an attribute from the use of a "#pragma
6894 GCC visibility push(...)"; in the latter case we still want other
6895 considerations to be able to overrule the #pragma. */
6897 || (TARGET_DLLIMPORT_DECL_ATTRIBUTES
6902 /* Set default visibility to whatever the user supplied with
6903 visibility_specified depending on #pragma GCC visibility. */
6905 {
6908 {
6911 /* If visibility changed and DECL already has DECL_RTL, ensure
6912 symbol flags are updated. */
6917 }
6918 }
6920 }
6922 /* Handle an "tls_model" attribute; arguments as in
6923 struct attribute_spec.handler. */
6925 static tree
6928 {
6929 tree id;
6936 {
6939 }
6944 {
6947 }
6957 else
6958 error ("tls_model argument must be one of \"local-exec\", \"initial-exec\", \"local-dynamic\" or \"global-dynamic\"");
6962 }
6964 /* Handle a "no_instrument_function" attribute; arguments as in
6965 struct attribute_spec.handler. */
6967 static tree
6972 {
6976 {
6980 }
6982 {
6986 }
6987 else
6991 }
6993 /* Handle a "malloc" attribute; arguments as in
6994 struct attribute_spec.handler. */
6996 static tree
6999 {
7003 else
7004 {
7007 }
7010 }
7012 /* Handle a "alloc_size" attribute; arguments as in
7013 struct attribute_spec.handler. */
7015 static tree
7018 {
7021 {
7028 {
7033 }
7034 }
7036 }
7038 /* Handle a "fn spec" attribute; arguments as in
7039 struct attribute_spec.handler. */
7041 static tree
7045 {
7050 }
7052 /* Handle a "returns_twice" attribute; arguments as in
7053 struct attribute_spec.handler. */
7055 static tree
7058 {
7061 else
7062 {
7065 }
7068 }
7070 /* Handle a "no_limit_stack" attribute; arguments as in
7071 struct attribute_spec.handler. */
7073 static tree
7078 {
7082 {
7086 }
7088 {
7092 }
7093 else
7097 }
7099 /* Handle a "pure" attribute; arguments as in
7100 struct attribute_spec.handler. */
7102 static tree
7105 {
7108 /* ??? TODO: Support types. */
7109 else
7110 {
7113 }
7116 }
7118 /* Handle a "no vops" attribute; arguments as in
7119 struct attribute_spec.handler. */
7121 static tree
7125 {
7129 }
7131 /* Handle a "deprecated" attribute; arguments as in
7132 struct attribute_spec.handler. */
7134 static tree
7138 {
7146 {
7149 }
7152 {
7162 else
7164 }
7166 {
7171 }
7172 else
7176 {
7179 {
7185 }
7188 else
7190 }
7193 }
7195 /* Handle a "vector_size" attribute; arguments as in
7196 struct attribute_spec.handler. */
7198 static tree
7202 {
7212 {
7215 }
7217 /* Get the vector size (in bytes). */
7220 /* We need to provide for vector pointers, vector arrays, and
7221 functions returning vectors. For example:
7223 __attribute__((vector_size(16))) short *foo;
7225 In this case, the mode is SI, but the type being modified is
7226 HI, so we need to look further. */
7235 /* Get the mode of the type being modified. */
7246 {
7249 }
7252 {
7255 }
7258 {
7261 }
7263 /* Calculate how many units fit in the vector. */
7266 {
7269 }
7273 /* Build back pointers if needed. */
7277 }
7279 /* Handle the "nonnull" attribute. */
7280 static tree
7284 {
7288 /* If no arguments are specified, all pointer arguments should be
7289 non-null. Verify a full prototype is given so that the arguments
7290 will have the correct types when we actually check them later. */
7292 {
7294 {
7297 }
7299 }
7301 /* Argument list specified. Verify that each argument number references
7302 a pointer argument. */
7304 {
7305 tree argument;
7309 {
7314 }
7318 {
7320 {
7324 }
7328 {
7333 }
7336 {
7341 }
7342 }
7343 }
7346 }
7348 /* Check the argument list of a function call for null in argument slots
7349 that are marked as requiring a non-null pointer argument. The NARGS
7350 arguments are passed in the array ARGARRAY.
7351 */
7353 static void
7355 {
7360 {
7362 {
7365 /* Walk the argument list. If we encounter an argument number we
7366 should check for non-null, do it. If the attribute has no args,
7367 then every pointer argument is checked (in which case the check
7368 for pointer type is done in check_nonnull_arg). */
7370 {
7375 }
7376 }
7377 }
7378 }
7380 /* Check that the Nth argument of a function call (counting backwards
7381 from the end) is a (pointer)0. The NARGS arguments are passed in the
7382 array ARGARRAY. */
7384 static void
7386 {
7390 {
7393 tree sentinel;
7395 /* Skip over the named arguments. */
7397 {
7399 len++;
7400 }
7403 {
7406 }
7408 /* The sentinel must be one of the varargs, i.e.
7409 in position >= the number of fixed arguments. */
7411 {
7415 }
7417 /* Validate the sentinel. */
7421 /* Although __null (in C++) is only an integer we allow it
7422 nevertheless, as we are guaranteed that it's exactly
7423 as wide as a pointer, and we don't want to force
7424 users to cast the NULL they have written there.
7425 We warn with -Wstrict-null-sentinel, though. */
7428 }
7429 }
7431 /* Helper for check_function_nonnull; given a list of operands which
7432 must be non-null in ARGS, determine if operand PARAM_NUM should be
7433 checked. */
7435 static bool
7437 {
7441 {
7448 }
7450 }
7452 /* Check that the function argument PARAM (which is operand number
7453 PARAM_NUM) is non-null. This is called by check_function_nonnull
7454 via check_function_arguments_recurse. */
7456 static void
7459 {
7460 /* Just skip checking the argument if it's not a pointer. This can
7461 happen if the "nonnull" attribute was given without an operand
7462 list (which means to check every pointer argument). */
7470 }
7472 /* Helper for nonnull attribute handling; fetch the operand number
7473 from the attribute argument list. */
7475 static bool
7477 {
7478 /* Verify the arg number is a constant. */
7485 }
7487 /* Handle a "nothrow" attribute; arguments as in
7488 struct attribute_spec.handler. */
7490 static tree
7493 {
7496 /* ??? TODO: Support types. */
7497 else
7498 {
7501 }
7504 }
7506 /* Handle a "cleanup" attribute; arguments as in
7507 struct attribute_spec.handler. */
7509 static tree
7512 {
7516 /* ??? Could perhaps support cleanups on TREE_STATIC, much like we do
7517 for global destructors in C++. This requires infrastructure that
7518 we don't have generically at the moment. It's also not a feature
7519 we'd be missing too much, since we do have attribute constructor. */
7521 {
7525 }
7527 /* Verify that the argument is a function in scope. */
7528 /* ??? We could support pointers to functions here as well, if
7529 that was considered desirable. */
7532 {
7536 }
7539 {
7543 }
7545 /* That the function has proper type is checked with the
7546 eventual call to build_function_call. */
7549 }
7551 /* Handle a "warn_unused_result" attribute. No special handling. */
7553 static tree
7557 {
7558 /* Ignore the attribute for functions not returning any value. */
7560 {
7563 }
7566 }
7568 /* Handle a "sentinel" attribute. */
7570 static tree
7573 {
7577 {
7581 }
7582 else
7583 {
7588 {
7592 }
7593 }
7596 {
7600 {
7604 }
7605 else
7606 {
7608 {
7612 }
7613 }
7614 }
7617 }
7619 /* Handle a "type_generic" attribute. */
7621 static tree
7625 {
7626 tree params;
7628 /* Ensure we have a function type. */
7635 /* Ensure we have a variadic function. */
7639 }
7641 /* Handle a "target" attribute. */
7643 static tree
7646 {
7647 /* Ensure we have a function type. */
7649 {
7652 }
7654 flags))
7658 }
7660 /* Arguments being collected for optimization. */
7667 /* Inner function to convert a TREE_LIST to argv string to parse the optimize
7668 options in ARGS. ATTR_P is true if this is for attribute(optimize), and
7669 false for #pragma GCC optimize. */
7671 bool
7673 {
7681 tree ap;
7683 /* Build up argv vector. Just in case the string is stored away, use garbage
7684 collected strings. */
7689 {
7693 {
7697 }
7700 {
7701 /* Split string into multiple substrings. */
7709 {
7716 {
7720 }
7721 else
7722 {
7725 }
7729 /* If the user supplied -Oxxx or -fxxx, only allow -Oxxx or -fxxx
7730 options. */
7732 {
7737 else
7741 }
7744 {
7747 /* Assume that Ox is -Ox, a numeric value is -Ox, a s by
7748 itself is -Os, and any other switch begins with a -f. */
7754 }
7759 }
7761 }
7762 }
7772 /* Now parse the options. */
7778 /* Don't allow changing -fstrict-aliasing. */
7783 }
7785 /* For handling "optimize" attribute. arguments as in
7786 struct attribute_spec.handler. */
7788 static tree
7791 {
7792 /* Ensure we have a function type. */
7794 {
7797 }
7798 else
7799 {
7803 /* Save current options. */
7806 /* If we previously had some optimization options, use them as the
7807 default. */
7811 /* Parse options, and update the vector. */
7816 /* Restore current options. */
7818 }
7821 }
7823 /* Handle a "no_split_stack" attribute. */
7825 static tree
7830 {
7834 {
7838 }
7840 {
7844 }
7847 }
7848 \f
7849 /* Check for valid arguments being passed to a function.
7850 ATTRS is a list of attributes. There are NARGS arguments in the array
7851 ARGARRAY. TYPELIST is the list of argument types for the function.
7852 */
7853 void
7855 {
7856 /* Check for null being passed in a pointer argument that must be
7857 non-null. We also need to do this if format checking is enabled. */
7862 /* Check for errors in format strings. */
7869 }
7871 /* Generic argument checking recursion routine. PARAM is the argument to
7872 be checked. PARAM_NUM is the number of the argument. CALLBACK is invoked
7873 once the argument is resolved. CTX is context for the callback. */
7874 void
7879 {
7883 {
7884 /* Strip coercion. */
7888 }
7891 {
7893 tree attrs;
7896 /* See if this is a call to a known internationalization function
7897 that modifies a format arg. Such a function may have multiple
7898 format_arg attributes (for example, ngettext). */
7901 attrs;
7904 {
7905 tree inner_arg;
7906 tree format_num_expr;
7909 call_expr_arg_iterator iter;
7911 /* Extract the argument number, which was previously checked
7912 to be valid. */
7924 {
7929 }
7930 }
7932 /* If we found a format_arg attribute and did a recursive check,
7933 we are done with checking this argument. Otherwise, we continue
7934 and this will be considered a non-literal. */
7937 }
7940 {
7941 /* Check both halves of the conditional expression. */
7947 }
7950 }
7952 /* Checks for a builtin function FNDECL that the number of arguments
7953 NARGS against the required number REQUIRED and issues an error if
7954 there is a mismatch. Returns true if the number of arguments is
7955 correct, otherwise false. */
7957 static bool
7959 {
7961 {
7965 }
7967 {
7971 }
7973 }
7975 /* Verifies the NARGS arguments ARGS to the builtin function FNDECL.
7976 Returns false if there was an error, otherwise true. */
7978 bool
7980 {
7986 {
7996 {
7998 {
8002 }
8004 }
8014 {
8021 {
8025 }
8027 }
8032 {
8037 {
8041 }
8044 {
8046 fndecl);
8048 }
8050 }
8055 }
8056 }
8058 /* Function to help qsort sort FIELD_DECLs by name order. */
8060 int
8062 {
8067 /* A nontype is "greater" than a type. */
8076 }
8079 gt_pointer_operator new_value;
8083 /* This routine compares two fields like field_decl_cmp but using the
8084 pointer operator in resort_data. */
8086 static int
8088 {
8093 /* A nontype is "greater" than a type. */
8099 {
8106 }
8108 }
8110 /* Resort DECL_SORTED_FIELDS because pointers have been reordered. */
8112 void
8115 gt_pointer_operator new_value,
8117 {
8122 resort_field_decl_cmp);
8123 }
8125 /* Subroutine of c_parse_error.
8126 Return the result of concatenating LHS and RHS. RHS is really
8127 a string literal, its first character is indicated by RHS_START and
8128 RHS_SIZE is its length (including the terminating NUL character).
8130 The caller is responsible for deleting the returned pointer. */
8134 {
8140 }
8142 /* Issue the error given by GMSGID, indicating that it occurred before
8143 TOKEN, which had the associated VALUE. */
8145 void
8148 {
8149 #define catenate_messages(M1, M2) catenate_strings ((M1), (M2), sizeof (M2))
8159 {
8164 {
8177 }
8181 else
8187 }
8197 {
8202 }
8208 {
8213 }
8214 else
8218 {
8221 }
8222 #undef catenate_messages
8223 }
8225 /* Mapping for cpp message reasons to the options that enable them. */
8227 struct reason_option_codes_t
8228 {
8231 };
8250 };
8252 /* Return the gcc option code associated with the reason for a cpp
8253 message, or 0 if none. */
8255 static int
8257 {
8261 {
8264 }
8266 }
8268 /* Callback from cpp_error for PFILE to print diagnostics from the
8269 preprocessor. The diagnostic is of type LEVEL, with REASON set
8270 to the reason code if LEVEL is represents a warning, at location
8271 LOCATION unless this is after lexing and the compiler's location
8272 should be used instead, with column number possibly overridden by
8273 COLUMN_OVERRIDE if not zero; MSG is the translated message and AP
8274 the arguments. Returns true if a diagnostic was emitted, false
8275 otherwise. */
8277 bool
8281 {
8282 diagnostic_info diagnostic;
8283 diagnostic_t dlevel;
8288 {
8293 /* Fall through. */
8318 }
8331 }
8333 /* Convert a character from the host to the target execution character
8334 set. cpplib handles this, mostly. */
8336 HOST_WIDE_INT
8338 {
8339 /* Character constants in GCC proper are sign-extended under -fsigned-char,
8340 zero-extended under -fno-signed-char. cpplib insists that characters
8341 and character constants are always unsigned. Hence we must convert
8342 back and forth. */
8350 else
8352 }
8354 /* Build the result of __builtin_offsetof. EXPR is a nested sequence of
8355 component references, with STOP_REF, or alternatively an INDIRECT_REF of
8356 NULL, at the bottom; much like the traditional rendering of offsetof as a
8357 macro. Returns the folded and properly cast result. */
8359 static tree
8361 {
8369 {
8385 {
8388 }
8398 {
8402 }
8416 {
8419 }
8423 /* Check if the offset goes beyond the upper bound of the array. */
8425 {
8431 {
8435 {
8436 tree v;
8443 {
8451 }
8452 /* Don't warn if the array might be considered a poor
8453 man's flexible array member with a very permissive
8454 definition thereof. */
8458 "index %E denotes an offset "
8461 }
8462 }
8463 }
8467 /* Handle static members of volatile structs. */
8474 }
8477 }
8479 tree
8481 {
8482 /* Convert back from the internal sizetype to size_t. */
8484 }
8486 /* Warn for A ?: C expressions (with B omitted) where A is a boolean
8487 expression, because B will always be true. */
8489 void
8491 {
8494 "the omitted middle operand in ?: will always be %<true%>, "
8496 }
8498 /* Print an error message for an invalid lvalue. USE says
8499 how the lvalue is being used and so selects the error message. */
8501 void
8503 {
8505 {
8523 }
8524 }
8525 \f
8526 /* *PTYPE is an incomplete array. Complete it with a domain based on
8527 INITIAL_VALUE. If INITIAL_VALUE is not present, use 1 if DO_DEFAULT
8528 is true. Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
8529 2 if INITIAL_VALUE was NULL, and 3 if INITIAL_VALUE was empty. */
8531 int
8533 {
8540 {
8542 {
8543 int eltsize
8546 }
8548 {
8552 {
8556 }
8557 else
8558 {
8559 tree curindex;
8572 cnt++)
8573 {
8577 else
8578 {
8582 size_one_node);
8583 }
8586 }
8589 }
8590 }
8591 else
8592 {
8593 /* Make an error message unless that happened already. */
8596 }
8597 }
8598 else
8599 {
8603 }
8610 else
8613 /* Using build_distinct_type_copy and modifying things afterward instead
8614 of using build_array_type to create a new type preserves all of the
8615 TYPE_LANG_FLAG_? bits that the front end may have set. */
8621 /* Make sure we have the canonical MAIN_TYPE. */
8624 hashcode);
8627 /* Fix the canonical type. */
8637 else
8642 else
8648 {
8650 /* If we proceed with the array type as it is, we'll eventually
8651 crash in tree_low_cst(). */
8653 }
8657 }
8659 \f
8660 /* Used to help initialize the builtin-types.def table. When a type of
8661 the correct size doesn't exist, use error_mark_node instead of NULL.
8662 The later results in segfaults even when a decl using the type doesn't
8663 get invoked. */
8665 tree
8667 {
8670 }
8672 /* A helper function for resolve_overloaded_builtin in resolving the
8673 overloaded __sync_ builtins. Returns a positive power of 2 if the
8674 first operand of PARAMS is a pointer to a supported data type.
8675 Returns 0 if an error is encountered. */
8677 static int
8679 {
8680 tree type;
8684 {
8687 }
8701 incompatible:
8704 }
8706 /* A helper function for resolve_overloaded_builtin. Adds casts to
8707 PARAMS to make arguments match up with those of FUNCTION. Drops
8708 the variadic arguments at the end. Returns false if some error
8709 was encountered; true on success. */
8711 static bool
8713 {
8715 tree ptype;
8718 /* We've declared the implementation functions to use "volatile void *"
8719 as the pointer parameter, so we shouldn't get any complaints from the
8720 call to check_function_arguments what ever type the user used. */
8724 /* For the rest of the values, we need to cast these to FTYPE, so that we
8725 don't get warnings for passing pointer types, etc. */
8728 {
8729 tree val;
8733 {
8736 }
8738 /* ??? Ideally for the first conversion we'd use convert_for_assignment
8739 so that we get warnings for anything that doesn't match the pointer
8740 type. This isn't portable across the C and C++ front ends atm. */
8747 }
8749 /* The definition of these primitives is variadic, with the remaining
8750 being "an optional list of variables protected by the memory barrier".
8751 No clue what that's supposed to mean, precisely, but we consider all
8752 call-clobbered variables to be protected so we're safe. */
8756 }
8758 /* A helper function for resolve_overloaded_builtin. Adds a cast to
8759 RESULT to make it match the type of the first pointer argument in
8760 PARAMS. */
8762 static tree
8764 {
8768 }
8770 /* Some builtin functions are placeholders for other expressions. This
8771 function should be called immediately after parsing the call expression
8772 before surrounding code has committed to the type of the expression.
8774 LOC is the location of the builtin call.
8776 FUNCTION is the DECL that has been invoked; it is known to be a builtin.
8777 PARAMS is the argument list for the call. The return value is non-null
8778 when expansion is complete, and null if normal processing should
8779 continue. */
8781 tree
8783 {
8786 {
8792 else
8796 }
8798 /* Handle BUILT_IN_NORMAL here. */
8800 {
8817 {
8835 }
8839 }
8840 }
8842 /* Ignoring their sign, return true if two scalar types are the same. */
8843 bool
8845 {
8852 /* Equality works here because c_common_signed_type uses
8853 TYPE_MAIN_VARIANT. */
8856 }
8858 /* Check for missing format attributes on function pointers. LTYPE is
8859 the new type or left-hand side type. RTYPE is the old type or
8860 right-hand side type. Returns TRUE if LTYPE is missing the desired
8861 attribute. */
8863 bool
8865 {
8867 tree ra;
8873 {
8874 tree la;
8879 }
8880 else
8882 }
8884 /* Subscripting with type char is likely to lose on a machine where
8885 chars are signed. So warn on any machine, but optionally. Don't
8886 warn for unsigned char since that type is safe. Don't warn for
8887 signed char because anyone who uses that must have done so
8888 deliberately. Furthermore, we reduce the false positive load by
8889 warning only for non-constant value of type char. */
8891 void
8893 {
8897 }
8899 /* Implement -Wparentheses for the unexpected C precedence rules, to
8900 cover cases like x + y << z which readers are likely to
8901 misinterpret. We have seen an expression in which CODE is a binary
8902 operator used to combine expressions ARG_LEFT and ARG_RIGHT, which
8903 before folding had CODE_LEFT and CODE_RIGHT. CODE_LEFT and
8904 CODE_RIGHT may be ERROR_MARK, which means that that side of the
8905 expression was not formed using a binary or unary operator, or it
8906 was enclosed in parentheses. */
8908 void
8912 {
8916 /* This macro tests that the expression ARG with original tree code
8917 CODE appears to be a boolean expression. or the result of folding a
8918 boolean expression. */
8919 #define APPEARS_TO_BE_BOOLEAN_EXPR_P(CODE, ARG) \
8920 (truth_value_p (TREE_CODE (ARG)) \
8921 || TREE_CODE (TREE_TYPE (ARG)) == BOOLEAN_TYPE \
8923 || ((CODE) != INTEGER_CST \
8924 && (integer_onep (ARG) || integer_zerop (ARG))))
8927 {
8959 /* Check cases like x|y==z */
8964 /* Check cases like !x | y */
8978 /* Check cases like x^y==z */
8992 /* Check cases like x&y==z */
8997 /* Check cases like !x & y */
9028 }
9029 #undef NOT_A_BOOLEAN_EXPR_P
9030 }
9032 /* If LABEL (a LABEL_DECL) has not been used, issue a warning. */
9034 void
9036 {
9038 {
9041 else
9043 }
9044 }
9046 #ifndef TARGET_HAS_TARGETCM
9048 #endif
9050 /* Warn for division by zero according to the value of DIVISOR. LOC
9051 is the location of the division operator. */
9053 void
9055 {
9056 /* If DIVISOR is zero, and has integral or fixed-point type, issue a warning
9057 about division by zero. Do not issue a warning if DIVISOR has a
9058 floating-point type, since we consider 0.0/0.0 a valid way of
9059 generating a NaN. */
9063 }
9065 /* Subroutine of build_binary_op. Give warnings for comparisons
9066 between signed and unsigned quantities that may fail. Do the
9067 checking based on the original operand trees ORIG_OP0 and ORIG_OP1,
9068 so that casts will be considered, but default promotions won't
9069 be.
9071 LOCATION is the location of the comparison operator.
9073 The arguments of this function map directly to local variables
9074 of build_binary_op. */
9076 void
9081 {
9086 /* In C++, check for comparison of different enum types. */
9092 {
9096 }
9098 /* Do not warn if the comparison is being done in a signed type,
9099 since the signed type will only be chosen if it can represent
9100 all the values of the unsigned type. */
9103 /* Do not warn if both operands are unsigned. */
9106 else
9107 {
9113 else
9121 /* Do not warn if the signed quantity is an unsuffixed integer
9122 literal (or some static constant expression involving such
9123 literals or a conditional expression involving such literals)
9124 and it is non-negative. */
9127 /* Do not warn if the comparison is an equality operation, the
9128 unsigned quantity is an integral constant, and it would fit
9129 in the result if the result were signed. */
9134 /* In C, do not warn if the unsigned quantity is an enumeration
9135 constant and its maximum value would fit in the result if the
9136 result were signed. */
9142 else
9144 OPT_Wsign_compare,
9146 }
9148 /* Warn if two unsigned values are being compared in a size larger
9149 than their original size, and one (and only one) is the result of
9150 a `~' operator. This comparison will always fail.
9152 Also warn if one operand is a constant, and the constant does not
9153 have all bits set that are set in the ~ operand when it is
9154 extended. */
9161 {
9168 {
9169 tree primop;
9175 {
9179 }
9180 else
9181 {
9185 }
9190 {
9193 {
9197 else
9200 }
9201 }
9202 }
9210 }
9211 }
9213 /* RESULT_TYPE is the result of converting TYPE1 and TYPE2 to a common
9214 type via c_common_type. If -Wdouble-promotion is in use, and the
9215 conditions for warning have been met, issue a warning. GMSGID is
9216 the warning message. It must have two %T specifiers for the type
9217 that was converted (generally "float") and the type to which it was
9218 converted (generally "double), respectively. LOC is the location
9219 to which the awrning should refer. */
9221 void
9224 {
9225 tree source_type;
9229 /* If the conversion will not occur at run-time, there is no need to
9230 warn about it. */
9242 else
9245 }
9247 /* Setup a TYPE_DECL node as a typedef representation.
9249 X is a TYPE_DECL for a typedef statement. Create a brand new
9250 ..._TYPE node (which will be just a variant of the existing
9251 ..._TYPE node with identical properties) and then install X
9252 as the TYPE_NAME of this brand new (duplicate) ..._TYPE node.
9254 The whole point here is to end up with a situation where each
9255 and every ..._TYPE node the compiler creates will be uniquely
9256 associated with AT MOST one node representing a typedef name.
9257 This way, even though the compiler substitutes corresponding
9258 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
9259 early on, later parts of the compiler can always do the reverse
9260 translation and get back the corresponding typedef name. For
9261 example, given:
9263 typedef struct S MY_TYPE;
9264 MY_TYPE object;
9266 Later parts of the compiler might only know that `object' was of
9267 type `struct S' if it were not for code just below. With this
9268 code however, later parts of the compiler see something like:
9270 struct S' == struct S
9271 typedef struct S' MY_TYPE;
9272 struct S' object;
9274 And they can then deduce (from the node for type struct S') that
9275 the original object declaration was:
9277 MY_TYPE object;
9279 Being able to do this is important for proper support of protoize,
9280 and also for generating precise symbolic debugging information
9281 which takes full account of the programmer's (typedef) vocabulary.
9283 Obviously, we don't want to generate a duplicate ..._TYPE node if
9284 the TYPE_DECL node that we are now processing really represents a
9285 standard built-in type. */
9287 void
9289 {
9293 {
9296 }
9299 {
9307 }
9308 }
9310 /* Record the types used by the current global variable declaration
9311 being parsed, so that we can decide later to emit their debug info.
9312 Those types are in types_used_by_cur_var_decl, and we are going to
9313 store them in the types_used_by_vars_hash hash table.
9314 DECL is the declaration of the global variable that has been parsed. */
9316 void
9318 {
9322 {
9325 }
9326 }
9328 /* The C and C++ parsers both use vectors to hold function arguments.
9329 For efficiency, we keep a cache of unused vectors. This is the
9330 cache. */
9337 /* Return a new vector from the cache. If the cache is empty,
9338 allocate a new vector. These vectors are GC'ed, so it is OK if the
9339 pointer is not released.. */
9343 {
9346 else
9347 {
9348 /* Passing 0 to VEC_alloc returns NULL, and our callers require
9349 that we always return a non-NULL value. The vector code uses
9350 4 when growing a NULL vector, so we do too. */
9352 }
9353 }
9355 /* Release a vector of trees back to the cache. */
9357 void
9359 {
9361 {
9364 }
9365 }
9367 /* Get a new tree vector holding a single tree. */
9371 {
9375 }
9377 /* Get a new tree vector which is a copy of an existing one. */
9381 {
9384 tree t;
9391 }