| blob | ff3526b03c307508d7f413393b0e77992e8d77ae |
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 };
370 /* Reserved words. The third field is a mask: keywords are disabled
371 if they match the mask.
373 Masks for languages:
374 C --std=c89: D_C99 | D_CXXONLY | D_OBJC | D_CXX_OBJC
375 C --std=c99: D_CXXONLY | D_OBJC
376 ObjC is like C except that D_OBJC and D_CXX_OBJC are not set
377 C++ --std=c98: D_CONLY | D_CXXOX | D_OBJC
378 C++ --std=c0x: D_CONLY | D_OBJC
379 ObjC++ is like C++ except that D_OBJC is not set
381 If -fno-asm is used, D_ASM is added to the mask. If
382 -fno-gnu-keywords is used, D_EXT is added. If -fno-asm and C in
383 C89 mode, D_EXT89 is added for both -fno-asm and -fno-gnu-keywords.
384 In C with -Wc++-compat, we warn if D_CXXWARN is set.
386 Note the complication of the D_CXX_OBJC keywords. These are
387 reserved words such as 'class'. In C++, 'class' is a reserved
388 word. In Objective-C++ it is too. In Objective-C, it is a
389 reserved word too, but only if it follows an '@' sign.
390 */
392 {
532 /* These Objective-C keywords are recognized only immediately after
533 an '@'. */
546 /* These are recognized only in protocol-qualifier context
547 (see above) */
554 };
559 /* Table of machine-independent attributes common to all C-like languages. */
561 {
562 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
564 handle_packed_attribute },
566 handle_nocommon_attribute },
568 handle_common_attribute },
569 /* FIXME: logically, noreturn attributes should be listed as
570 "false, true, true" and apply to function types. But implementing this
571 would require all the places in the compiler that use TREE_THIS_VOLATILE
572 on a decl to identify non-returning functions to be located and fixed
573 to check the function type instead. */
575 handle_noreturn_attribute },
577 handle_noreturn_attribute },
579 handle_noinline_attribute },
581 handle_noclone_attribute },
583 handle_leaf_attribute },
585 handle_always_inline_attribute },
587 handle_gnu_inline_attribute },
589 handle_artificial_attribute },
591 handle_flatten_attribute },
593 handle_used_attribute },
595 handle_unused_attribute },
597 handle_externally_visible_attribute },
598 /* The same comments as for noreturn attributes apply to const ones. */
600 handle_const_attribute },
602 handle_transparent_union_attribute },
604 handle_constructor_attribute },
606 handle_destructor_attribute },
608 handle_mode_attribute },
610 handle_section_attribute },
612 handle_aligned_attribute },
614 handle_weak_attribute },
616 handle_ifunc_attribute },
618 handle_alias_attribute },
620 handle_weakref_attribute },
622 handle_no_instrument_function_attribute },
624 handle_malloc_attribute },
626 handle_returns_twice_attribute },
628 handle_no_limit_stack_attribute },
630 handle_pure_attribute },
631 /* For internal use (marking of builtins) only. The name contains space
632 to prevent its usage in source code. */
634 handle_novops_attribute },
636 handle_deprecated_attribute },
638 handle_vector_size_attribute },
640 handle_visibility_attribute },
642 handle_tls_model_attribute },
644 handle_nonnull_attribute },
646 handle_nothrow_attribute },
649 handle_cleanup_attribute },
651 handle_warn_unused_result_attribute },
653 handle_sentinel_attribute },
654 /* For internal use (marking of builtins) only. The name contains space
655 to prevent its usage in source code. */
657 handle_type_generic_attribute },
659 handle_alloc_size_attribute },
661 handle_cold_attribute },
663 handle_hot_attribute },
665 handle_error_attribute },
667 handle_error_attribute },
669 handle_target_attribute },
671 handle_optimize_attribute },
673 handle_no_split_stack_attribute },
674 /* For internal use (marking of builtins and runtime functions) only.
675 The name contains space to prevent its usage in source code. */
677 handle_fnspec_attribute },
679 };
681 /* Give the specifications for the format attributes, used by C and all
682 descendants. */
685 {
686 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
688 handle_format_attribute },
690 handle_format_arg_attribute },
692 };
694 /* Return identifier for address space AS. */
698 {
702 }
704 /* Push current bindings for the function name VAR_DECLS. */
706 void
708 {
713 {
717 {
720 }
721 }
723 /* Normally they'll have been NULL, so only push if we've got a
724 stack, or they are non-NULL. */
726 saved_function_name_decls);
727 }
729 /* Finish up the current bindings, adding them into the current function's
730 statement tree. This must be done _before_ finish_stmt_tree is called.
731 If there is no current function, we must be at file scope and no statements
732 are involved. Pop the previous bindings. */
734 void
736 {
745 {
753 }
759 {
760 /* We had saved values, restore them. */
761 tree saved;
764 {
769 }
771 }
773 }
775 /* Return the text name of the current function, suitably prettified
776 by PRETTY_P. Return string must be freed by caller. */
780 {
787 {
790 }
803 {
806 }
809 }
811 /* Return the VAR_DECL for a const char array naming the current
812 function. If the VAR_DECL has not yet been created, create it
813 now. RID indicates how it should be formatted and IDENTIFIER_NODE
814 ID is its name (unfortunately C and C++ hold the RID values of
815 keywords in different places, so we can't derive RID from ID in
816 this language independent code. LOC is the location of the
817 function. */
819 tree
821 {
831 {
832 /* If a tree is built here, it would normally have the lineno of
833 the current statement. Later this tree will be moved to the
834 beginning of the function and this line number will be wrong.
835 To avoid this problem set the lineno to 0 here; that prevents
836 it from appearing in the RTL. */
837 tree stmts;
845 saved_function_name_decls
849 }
854 }
856 /* Given a STRING_CST, give it a suitable array-of-chars data type. */
858 tree
860 {
865 /* Compute the number of elements, for the array type. */
867 {
870 }
872 {
875 }
877 {
880 }
881 else
882 {
885 }
887 /* C89 2.2.4.1, C99 5.2.4.1 (Translation limits). The analogous
888 limit in C++98 Annex B is very large (65536) and is not normative,
889 so we do not diagnose it (warn_overlength_strings is forced off
890 in c_common_post_options). */
892 {
896 /* Translators: The %d after 'ISO C' will be 90 or 99. Do not
897 separate the %d from the 'C'. 'ISO' should not be
898 translated, but it may be moved after 'C%d' in languages
899 where modifiers follow nouns. */
901 "string length %qd is greater than the length %qd "
904 }
906 /* Create the array type for the string constant. The ISO C++
907 standard says that a string literal has type `const char[N]' or
908 `const wchar_t[N]'. We use the same logic when invoked as a C
909 front-end with -Wwrite-strings.
910 ??? We should change the type of an expression depending on the
911 state of a warning flag. We should just be warning -- see how
912 this is handled in the C++ front-end for the deprecated implicit
913 conversion from string literals to `char*' or `wchar_t*'.
915 The C++ front end relies on TYPE_MAIN_VARIANT of a cv-qualified
916 array type being the unqualified version of that type.
917 Therefore, if we are constructing an array of const char, we must
918 construct the matching unqualified array type first. The C front
919 end does not require this, but it does no harm, so we do it
920 unconditionally. */
931 }
932 \f
933 /* Fully fold EXPR, an expression that was not folded (beyond integer
934 constant expressions and null pointer constants) when being built
935 up. If IN_INIT, this is in a static initializer and certain
936 changes are made to the folding done. Clear *MAYBE_CONST if
937 MAYBE_CONST is not NULL and EXPR is definitely not a constant
938 expression because it contains an evaluated operator (in C99) or an
939 operator outside of sizeof returning an integer constant (in C90)
940 not permitted in constant expressions, or because it contains an
941 evaluated arithmetic overflow. (*MAYBE_CONST should typically be
942 set to true by callers before calling this function.) Return the
943 folded expression. Function arguments have already been folded
944 before calling this function, as have the contents of SAVE_EXPR,
945 TARGET_EXPR, BIND_EXPR, VA_ARG_EXPR, OBJ_TYPE_REF and
946 C_MAYBE_CONST_EXPR. */
948 tree
950 {
951 tree ret;
957 /* This function is not relevant to C++ because C++ folds while
958 parsing, and may need changes to be correct for C++ when C++
959 stops folding while parsing. */
966 {
969 }
976 }
978 /* Internal helper for c_fully_fold. EXPR and IN_INIT are as for
979 c_fully_fold. *MAYBE_CONST_OPERANDS is cleared because of operands
980 not permitted, while *MAYBE_CONST_ITSELF is cleared because of
981 arithmetic overflow (for C90, *MAYBE_CONST_OPERANDS is carried from
982 both evaluated and unevaluated subexpressions while
983 *MAYBE_CONST_ITSELF is carried from only evaluated
984 subexpressions). */
986 static tree
989 {
1001 /* This function is not relevant to C++ because C++ folds while
1002 parsing, and may need changes to be correct for C++ when C++
1003 stops folding while parsing. */
1007 /* Constants, declarations, statements, errors, SAVE_EXPRs and
1008 anything else not counted as an expression cannot usefully be
1009 folded further at this point. */
1015 /* Operands of variable-length expressions (function calls) have
1016 already been folded, as have __builtin_* function calls, and such
1017 expressions cannot occur in constant expressions. */
1019 {
1023 }
1026 {
1035 else
1038 }
1040 /* Assignment, increment, decrement, function call and comma
1041 operators, and statement expressions, cannot occur in constant
1042 expressions if evaluated / outside of sizeof. (Function calls
1043 were handled above, though VA_ARG_EXPR is treated like a function
1044 call here, and statement expressions are handled through
1045 C_MAYBE_CONST_EXPR to avoid folding inside them.) */
1047 {
1067 }
1069 /* Fold individual tree codes as appropriate. */
1071 {
1073 /* Any non-constancy will have been marked in a containing
1074 C_MAYBE_CONST_EXPR; there is no more folding to do here. */
1082 maybe_const_itself);
1087 {
1090 }
1099 maybe_const_itself);
1102 maybe_const_itself);
1108 {
1112 }
1154 /* Binary operations evaluating both arguments (increment and
1155 decrement are binary internally in GCC). */
1159 maybe_const_itself);
1167 /* The RHS of a MODIFY_EXPR was fully folded when building that
1168 expression for the sake of conversion warnings. */
1171 maybe_const_itself);
1175 ret = in_init
1178 else
1189 CASE_CONVERT:
1198 /* Unary operations. */
1201 maybe_const_itself);
1206 ret = in_init
1209 else
1214 {
1218 }
1220 {
1223 CASE_CONVERT:
1224 /* Don't warn about explicit conversions. We will already
1225 have warned about suspect implicit conversions. */
1232 }
1237 /* Binary operations not necessarily evaluating both
1238 arguments. */
1245 ? truthvalue_false_node
1253 ret = in_init
1256 else
1261 && op0_const
1262 && op0_const_self
1268 && op0_const_self
1294 else
1299 && op0_const
1300 && op0_const_self
1304 && op0_const_self
1308 && op0_const
1309 && op0_const_self
1313 && op0_const_self
1319 /* Each case where an operand with excess precision may be
1320 encountered must remove the EXCESS_PRECISION_EXPR around
1321 inner operands and possibly put one around the whole
1322 expression or possibly convert to the semantic type (which
1323 c_fully_fold does); we cannot tell at this stage which is
1324 appropriate in any particular case. */
1328 /* Various codes may appear through folding built-in functions
1329 and their arguments. */
1331 }
1333 out:
1334 /* Some folding may introduce NON_LVALUE_EXPRs; all lvalue checks
1335 have been done by this point, so remove them again. */
1339 {
1343 }
1347 }
1349 /* If not optimizing, EXP is not a VAR_DECL, or EXP has array type,
1350 return EXP. Otherwise, return either EXP or its known constant
1351 value (if it has one), but return EXP if EXP has mode BLKmode. ???
1352 Is the BLKmode test appropriate? */
1354 tree
1356 {
1357 tree ret;
1359 /* This function is only used by C, for c_fully_fold and other
1360 optimization, and may not be correct for C++. */
1371 /* Avoid unwanted tree sharing between the initializer and current
1372 function's body where the tree can be modified e.g. by the
1373 gimplifier. */
1377 }
1379 /* Print a warning if a constant expression had overflow in folding.
1380 Invoke this function on every expression that the language
1381 requires to be a constant expression.
1382 Note the ANSI C standard says it is erroneous for a
1383 constant expression to overflow. */
1385 void
1387 {
1395 }
1397 /* The same as above but print an unconditional error. */
1398 void
1400 {
1407 }
1409 /* Print a warning if an expression had overflow in folding and its
1410 operands hadn't.
1412 Invoke this function on every expression that
1413 (1) appears in the source code, and
1414 (2) is a constant expression that overflowed, and
1415 (3) is not already checked by convert_and_check;
1416 however, do not invoke this function on operands of explicit casts
1417 or when the expression is the result of an operator and any operand
1418 already overflowed. */
1420 void
1422 {
1427 {
1456 }
1457 }
1459 /* Warn about uses of logical || / && operator in a context where it
1460 is likely that the bitwise equivalent was intended by the
1461 programmer. We have seen an expression in which CODE is a binary
1462 operator used to combine expressions OP_LEFT and OP_RIGHT, which before folding
1463 had CODE_LEFT and CODE_RIGHT, into an expression of type TYPE. */
1464 void
1468 {
1480 /* Warn if &&/|| are being used in a context where it is
1481 likely that the bitwise equivalent was intended by the
1482 programmer. That is, an expression such as op && MASK
1483 where op should not be any boolean expression, nor a
1484 constant, and mask seems to be a non-boolean integer constant. */
1492 {
1496 else
1501 }
1503 /* We do not warn for constants because they are typical of macro
1504 expansions that test for features. */
1508 /* This warning only makes sense with logical operands. */
1524 /* If this is an OR operation, invert both sides; we will invert
1525 again at the end. */
1529 /* If both expressions are the same, if we can merge the ranges, and we
1530 can build the range test, return it or it inverted. */
1536 {
1542 "logical %<or%> "
1544 else
1546 "logical %<and%> "
1548 }
1549 }
1552 /* Print a warning about casts that might indicate violation
1553 of strict aliasing rules if -Wstrict-aliasing is used and
1554 strict aliasing mode is in effect. OTYPE is the original
1555 TREE_TYPE of EXPR, and TYPE the type we're casting to. */
1557 bool
1559 {
1560 /* Strip pointer conversion chains and get to the correct original type. */
1568 /* If the type we are casting to is a ref-all pointer
1569 dereferencing it is always valid. */
1576 {
1577 /* Casting the address of an object to non void pointer. Warn
1578 if the cast breaks type based aliasing. */
1580 {
1584 }
1585 else
1586 {
1587 /* warn_strict_aliasing >= 3. This includes the default (3).
1588 Only warn if the cast is dereferenced immediately. */
1589 alias_set_type set1 =
1595 {
1599 }
1602 {
1606 }
1607 }
1608 }
1609 else
1611 {
1612 /* At this level, warn for any conversions, even if an address is
1613 not taken in the same statement. This will likely produce many
1614 false positives, but could be useful to pinpoint problems that
1615 are not revealed at higher levels. */
1620 {
1624 }
1625 }
1628 }
1630 /* Warn for unlikely, improbable, or stupid DECL declarations
1631 of `main'. */
1633 void
1635 {
1636 tree args;
1641 {
1649 {
1653 decl);
1662 decl);
1673 }
1674 }
1676 /* It is intentional that this message does not mention the third
1677 argument because it's only mentioned in an appendix of the
1678 standard. */
1681 }
1683 /* True if pointers to distinct types T1 and T2 can be converted to
1684 each other without an explicit cast. Only returns true for opaque
1685 vector types. */
1686 bool
1688 {
1695 }
1697 /* True if vector types T1 and T2 can be converted to each other
1698 without an explicit cast. If EMIT_LAX_NOTE is true, and T1 and T2
1699 can only be converted with -flax-vector-conversions yet that is not
1700 in effect, emit a note telling the user about that option if such
1701 a note has not previously been emitted. */
1702 bool
1704 {
1712 convertible_lax =
1727 {
1730 "conversions between vectors with differing "
1732 }
1735 }
1737 /* This is a helper function of build_binary_op.
1739 For certain operations if both args were extended from the same
1740 smaller type, do the arithmetic in that type and then extend.
1742 BITWISE indicates a bitwise operation.
1743 For them, this optimization is safe only if
1744 both args are zero-extended or both are sign-extended.
1745 Otherwise, we might change the result.
1746 Eg, (short)-1 | (unsigned short)-1 is (int)-1
1747 but calculated in (unsigned short) it would be (unsigned short)-1.
1748 */
1750 {
1754 tree type;
1756 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents
1757 excessive narrowing when we call get_narrower below. For
1758 example, suppose that OP0 is of unsigned int extended
1759 from signed char and that RESULT_TYPE is long long int.
1760 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look
1761 like
1763 (long long int) (unsigned int) signed_char
1765 which get_narrower would narrow down to
1767 (unsigned int) signed char
1769 If we do not cast OP0 first, get_narrower would return
1770 signed_char, which is inconsistent with the case of the
1771 explicit cast. */
1778 /* UNS is 1 if the operation to be done is an unsigned one. */
1781 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
1782 but it *requires* conversion to FINAL_TYPE. */
1793 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
1795 /* For bitwise operations, signedness of nominal type
1796 does not matter. Consider only how operands were extended. */
1800 /* Note that in all three cases below we refrain from optimizing
1801 an unsigned operation on sign-extended args.
1802 That would not be valid. */
1804 /* Both args variable: if both extended in same way
1805 from same width, do it in that width.
1806 Do it unsigned if args were zero-extended. */
1813 return c_common_signed_or_unsigned_type
1820 && (type
1831 && (type
1839 }
1841 /* Warns if the conversion of EXPR to TYPE may alter a value.
1842 This is a helper function for warnings_for_convert_and_check. */
1844 static void
1846 {
1858 /* If any operand is artificial, then this expression was generated
1859 by the compiler and we do not warn. */
1861 {
1865 }
1868 {
1881 /* Conversion from boolean to a signed:1 bit-field (which only
1882 can hold the values 0 and -1) doesn't lose information - but
1883 it does change the value. */
1892 /* Warn for real constant that is not an exact integer converted
1893 to integer type. */
1896 {
1899 }
1900 /* Warn for an integer constant that does not fit into integer type. */
1904 {
1912 else
1914 }
1916 {
1917 /* Warn for an integer constant that does not fit into real type. */
1919 {
1923 }
1924 /* Warn for a real constant that does not fit into a smaller
1925 real type. */
1928 {
1932 }
1933 }
1943 {
1944 /* In case of COND_EXPR, if both operands are constants or
1945 COND_EXPR, then we do not care about the type of COND_EXPR,
1946 only about the conversion of each operand. */
1954 {
1958 }
1959 /* Fall through. */
1960 }
1964 /* Warn for real types converted to integer types. */
1971 {
1972 /* Don't warn about unsigned char y = 0xff, x = (int) y; */
1976 /* Don't warn for short y; short x = ((int)y & 0xff); */
1980 {
1981 /* If both args were extended from a shortest type,
1982 use that type if that is safe. */
1989 {
1995 /* If one of the operands is a non-negative constant
1996 that fits in the target type, then the type of the
1997 other operand does not matter. */
2006 /* If constant is unsigned and fits in the target
2007 type, then the result will also fit. */
2009 && unsigned0
2012 && unsigned1
2015 }
2016 }
2017 /* Warn for integer types converted to smaller integer types. */
2021 /* When they are the same width but different signedness,
2022 then the value may change. */
2025 /* Even when converted to a bigger type, if the type is
2026 unsigned but expr is signed, then negative values
2027 will be changed. */
2032 }
2034 /* Warn for integer types converted to real types if and only if
2035 all the range of values of the integer type cannot be
2036 represented by the real type. */
2039 {
2043 /* Don't warn about char y = 0xff; float x = (int) y; */
2055 }
2057 /* Warn for real types converted to smaller real types. */
2068 }
2069 }
2071 /* Produce warnings after a conversion. RESULT is the result of
2072 converting EXPR to TYPE. This is a helper function for
2073 convert_and_check and cp_convert_and_check. */
2075 void
2077 {
2082 {
2083 /* Do not diagnose overflow in a constant expression merely
2084 because a conversion overflowed. */
2089 {
2090 /* This detects cases like converting -129 or 256 to
2091 unsigned char. */
2095 else
2097 }
2101 /* No warning for converting 0x80000000 to int. */
2109 else
2111 }
2116 else
2118 }
2121 /* Convert EXPR to TYPE, warning about conversion problems with constants.
2122 Invoke this function on every expression that is converted implicitly,
2123 i.e. because of language rules and not because of an explicit cast. */
2125 tree
2127 {
2128 tree result;
2129 tree expr_for_warning;
2131 /* Convert from a value with possible excess precision rather than
2132 via the semantic type, but do not warn about values not fitting
2133 exactly in the semantic type. */
2135 {
2141 }
2142 else
2156 }
2157 \f
2158 /* A node in a list that describes references to variables (EXPR), which are
2159 either read accesses if WRITER is zero, or write accesses, in which case
2160 WRITER is the parent of EXPR. */
2161 struct tlist
2162 {
2165 };
2167 /* Used to implement a cache the results of a call to verify_tree. We only
2168 use this for SAVE_EXPRs. */
2169 struct tlist_cache
2170 {
2174 tree expr;
2175 };
2177 /* Obstack to use when allocating tlist structures, and corresponding
2178 firstobj. */
2182 /* Keep track of the identifiers we've warned about, so we can avoid duplicate
2183 warnings. */
2185 /* SAVE_EXPRs need special treatment. We process them only once and then
2186 cache the results. */
2198 /* Create a new struct tlist and fill in its fields. */
2201 {
2208 }
2210 /* Add duplicates of the nodes found in ADD to the list *TO. If EXCLUDE_WRITER
2211 is nonnull, we ignore any node we find which has a writer equal to it. */
2213 static void
2215 {
2217 {
2224 }
2225 }
2227 /* Merge the nodes of ADD into TO. This merging process is done so that for
2228 each variable that already exists in TO, no new node is added; however if
2229 there is a write access recorded in ADD, and an occurrence on TO is only
2230 a read access, then the occurrence in TO will be modified to record the
2231 write. */
2233 static void
2235 {
2242 {
2249 {
2253 }
2255 {
2259 }
2261 }
2262 }
2264 /* WRITTEN is a variable, WRITER is its parent. Warn if any of the variable
2265 references in list LIST conflict with it, excluding reads if ONLY writers
2266 is nonzero. */
2268 static void
2271 {
2274 /* Avoid duplicate warnings. */
2280 {
2284 {
2290 }
2292 }
2293 }
2295 /* Given a list LIST of references to variables, find whether any of these
2296 can cause conflicts due to missing sequence points. */
2298 static void
2300 {
2304 {
2307 }
2308 }
2310 /* Return nonzero if X is a tree that can be verified by the sequence point
2311 warnings. */
2312 static int
2314 {
2315 /* !VOID_TYPE_P (TREE_TYPE (x)) is workaround for cp/tree.c
2316 (lvalue_p) crash on TRY/CATCH. */
2319 }
2321 /* Return nonzero if X and Y appear to be the same candidate (or NULL) */
2322 static bool
2324 {
2326 }
2328 /* Walk the tree X, and record accesses to variables. If X is written by the
2329 parent tree, WRITER is the parent.
2330 We store accesses in one of the two lists: PBEFORE_SP, and PNO_SP. If this
2331 expression or its only operand forces a sequence point, then everything up
2332 to the sequence point is stored in PBEFORE_SP. Everything else gets stored
2333 in PNO_SP.
2334 Once we return, we will have emitted warnings if any subexpression before
2335 such a sequence point could be undefined. On a higher level, however, the
2336 sequence point may not be relevant, and we'll merge the two lists.
2338 Example: (b++, a) + b;
2339 The call that processes the COMPOUND_EXPR will store the increment of B
2340 in PBEFORE_SP, and the use of A in PNO_SP. The higher-level call that
2341 processes the PLUS_EXPR will need to merge the two lists so that
2342 eventually, all accesses end up on the same list (and we'll warn about the
2343 unordered subexpressions b++ and b.
2345 A note on merging. If we modify the former example so that our expression
2346 becomes
2347 (b++, b) + a
2348 care must be taken not simply to add all three expressions into the final
2349 PNO_SP list. The function merge_tlist takes care of that by merging the
2350 before-SP list of the COMPOUND_EXPR into its after-SP list in a special
2351 way, so that no more than one access to B is recorded. */
2353 static void
2355 tree writer)
2356 {
2361 /* X may be NULL if it is the operand of an empty statement expression
2362 ({ }). */
2366 restart:
2374 {
2406 /* Rather than add both tmp_nosp and tmp_list2, we have to merge the
2407 two first, to avoid warning for (a ? b++ : b++). */
2423 /* Expressions inside the LHS are not ordered wrt. the sequence points
2424 in the RHS. Example:
2425 *a = (a++, 2)
2426 Despite the fact that the modification of "a" is in the before_sp
2427 list (tmp_before), it conflicts with the use of "a" in the LHS.
2428 We can handle this by adding the contents of tmp_list3
2429 to those of tmp_before, and redoing the collision warnings for that
2430 list. */
2433 /* Exclude the LHS itself here; we first have to merge it into the
2434 tmp_nosp list. This is done to avoid warning for "a = a"; if we
2435 didn't exclude the LHS, we'd get it twice, once as a read and once
2436 as a write. */
2447 /* We need to warn about conflicts among arguments and conflicts between
2448 args and the function address. Side effects of the function address,
2449 however, are not ordered by the sequence point of the call. */
2450 {
2451 call_expr_arg_iterator iter;
2452 tree arg;
2456 {
2461 }
2466 }
2469 /* Scan all the list, e.g. indices of multi dimensional array. */
2471 {
2477 }
2481 {
2488 {
2500 {
2504 }
2507 }
2511 }
2521 /* For other expressions, simply recurse on their operands.
2522 Manual tail recursion for unary expressions.
2523 Other non-expressions need not be processed. */
2525 {
2529 }
2531 {
2535 {
2540 }
2541 }
2543 }
2544 }
2546 /* Try to warn for undefined behavior in EXPR due to missing sequence
2547 points. */
2549 DEBUG_FUNCTION void
2551 {
2557 {
2560 }
2565 }
2566 \f
2567 /* Validate the expression after `case' and apply default promotions. */
2569 static tree
2571 {
2575 /* ??? Can we ever get nops here for a valid case value? We
2576 shouldn't for C. */
2578 /* In C++, the following is allowed:
2580 const int i = 3;
2581 switch (...) { case i: ... }
2583 So, we try to reduce the VALUE to a constant that way. */
2585 {
2589 }
2592 /* Promote char or short to int. */
2595 {
2598 }
2603 }
2604 \f
2605 /* See if the case values LOW and HIGH are in the range of the original
2606 type (i.e. before the default conversion to int) of the switch testing
2607 expression.
2608 TYPE is the promoted type of the testing expression, and ORIG_TYPE is
2609 the type before promoting it. CASE_LOW_P is a pointer to the lower
2610 bound of the case label, and CASE_HIGH_P is the upper bound or NULL
2611 if the case is not a case range.
2612 The caller has to make sure that we are not called with NULL for
2613 CASE_LOW_P (i.e. the default case).
2614 Returns true if the case label is in range of ORIG_TYPE (saturated or
2615 untouched) or false if the label is out of range. */
2617 static bool
2620 {
2625 /* If there was a problem with the original type, do nothing. */
2632 /* Case label is less than minimum for type. */
2635 {
2638 }
2640 /* Case value is greater than maximum for type. */
2643 {
2646 }
2648 /* Saturate lower case label value to minimum. */
2651 {
2655 }
2657 /* Saturate upper case label value to maximum. */
2660 {
2664 }
2672 }
2673 \f
2674 /* Return an integer type with BITS bits of precision,
2675 that is unsigned if UNSIGNEDP is nonzero, otherwise signed. */
2677 tree
2679 {
2718 }
2720 /* Return a fixed-point type that has at least IBIT ibits and FBIT fbits
2721 that is unsigned if UNSIGNEDP is nonzero, otherwise signed;
2722 and saturating if SATP is nonzero, otherwise not saturating. */
2724 tree
2727 {
2731 else
2739 {
2741 "fixed-point types that have too many integral and "
2744 }
2747 }
2749 /* Used for communication between c_common_type_for_mode and
2750 c_register_builtin_type. */
2753 /* Return a data type that has machine mode MODE.
2754 If the mode is an integer,
2755 then UNSIGNEDP selects between signed and unsigned types.
2756 If the mode is a fixed-point mode,
2757 then UNSIGNEDP selects between saturating and nonsaturating types. */
2759 tree
2761 {
2762 tree t;
2799 #if HOST_BITS_PER_WIDE_INT >= 64
2802 #endif
2827 {
2829 tree inner_type;
2845 }
2847 {
2852 }
2862 {
2948 }
2955 }
2957 tree
2959 {
2961 }
2963 /* Return a signed type the same as TYPE in other respects. */
2965 tree
2967 {
2969 }
2971 /* Return a type the same as TYPE except unsigned or
2972 signed according to UNSIGNEDP. */
2974 tree
2976 {
2977 tree type1;
2979 /* This block of code emulates the behavior of the old
2980 c_common_unsigned_type. In particular, it returns
2981 long_unsigned_type_node if passed a long, even when a int would
2982 have the same size. This is necessary for warnings to work
2983 correctly in archs where sizeof(int) == sizeof(long) */
2986 if (type1 == signed_char_type_node || type1 == char_type_node || type1 == unsigned_char_type_node)
3002 #if HOST_BITS_PER_WIDE_INT >= 64
3005 #endif
3015 #define C_COMMON_FIXED_TYPES(NAME) \
3016 if (type1 == short_ ## NAME ## _type_node \
3017 || type1 == unsigned_short_ ## NAME ## _type_node) \
3018 return unsignedp ? unsigned_short_ ## NAME ## _type_node \
3019 : short_ ## NAME ## _type_node; \
3020 if (type1 == NAME ## _type_node \
3021 || type1 == unsigned_ ## NAME ## _type_node) \
3022 return unsignedp ? unsigned_ ## NAME ## _type_node \
3023 : NAME ## _type_node; \
3024 if (type1 == long_ ## NAME ## _type_node \
3025 || type1 == unsigned_long_ ## NAME ## _type_node) \
3026 return unsignedp ? unsigned_long_ ## NAME ## _type_node \
3027 : long_ ## NAME ## _type_node; \
3028 if (type1 == long_long_ ## NAME ## _type_node \
3029 || type1 == unsigned_long_long_ ## NAME ## _type_node) \
3030 return unsignedp ? unsigned_long_long_ ## NAME ## _type_node \
3031 : long_long_ ## NAME ## _type_node;
3033 #define C_COMMON_FIXED_MODE_TYPES(NAME) \
3034 if (type1 == NAME ## _type_node \
3035 || type1 == u ## NAME ## _type_node) \
3036 return unsignedp ? u ## NAME ## _type_node \
3037 : NAME ## _type_node;
3039 #define C_COMMON_FIXED_TYPES_SAT(NAME) \
3040 if (type1 == sat_ ## short_ ## NAME ## _type_node \
3041 || type1 == sat_ ## unsigned_short_ ## NAME ## _type_node) \
3042 return unsignedp ? sat_ ## unsigned_short_ ## NAME ## _type_node \
3043 : sat_ ## short_ ## NAME ## _type_node; \
3044 if (type1 == sat_ ## NAME ## _type_node \
3045 || type1 == sat_ ## unsigned_ ## NAME ## _type_node) \
3046 return unsignedp ? sat_ ## unsigned_ ## NAME ## _type_node \
3047 : sat_ ## NAME ## _type_node; \
3048 if (type1 == sat_ ## long_ ## NAME ## _type_node \
3049 || type1 == sat_ ## unsigned_long_ ## NAME ## _type_node) \
3050 return unsignedp ? sat_ ## unsigned_long_ ## NAME ## _type_node \
3051 : sat_ ## long_ ## NAME ## _type_node; \
3052 if (type1 == sat_ ## long_long_ ## NAME ## _type_node \
3053 || type1 == sat_ ## unsigned_long_long_ ## NAME ## _type_node) \
3054 return unsignedp ? sat_ ## unsigned_long_long_ ## NAME ## _type_node \
3055 : sat_ ## long_long_ ## NAME ## _type_node;
3057 #define C_COMMON_FIXED_MODE_TYPES_SAT(NAME) \
3058 if (type1 == sat_ ## NAME ## _type_node \
3059 || type1 == sat_ ## u ## NAME ## _type_node) \
3060 return unsignedp ? sat_ ## u ## NAME ## _type_node \
3061 : sat_ ## NAME ## _type_node;
3087 /* For ENUMERAL_TYPEs in C++, must check the mode of the types, not
3088 the precision; they have precision set to match their range, but
3089 may use a wider mode to match an ABI. If we change modes, we may
3090 wind up with bad conversions. For INTEGER_TYPEs in C, must check
3091 the precision as well, so as to yield correct results for
3092 bit-field types. C++ does not have these separate bit-field
3093 types, and producing a signed or unsigned variant of an
3094 ENUMERAL_TYPE may cause other problems as well. */
3100 #define TYPE_OK(node) \
3101 (TYPE_MODE (type) == TYPE_MODE (node) \
3102 && TYPE_PRECISION (type) == TYPE_PRECISION (node))
3121 #if HOST_BITS_PER_WIDE_INT >= 64
3124 #endif
3133 #undef TYPE_OK
3136 }
3138 /* Build a bit-field integer type for the given WIDTH and UNSIGNEDP. */
3140 tree
3142 {
3143 /* Extended integer types of the same width as a standard type have
3144 lesser rank, so those of the same width as int promote to int or
3145 unsigned int and are valid for printf formats expecting int or
3146 unsigned int. To avoid such special cases, avoid creating
3147 extended integer types for bit-fields if a standard integer type
3148 is available. */
3165 }
3167 /* The C version of the register_builtin_type langhook. */
3169 void
3171 {
3172 tree decl;
3182 }
3183 \f
3184 /* Print an error message for invalid operands to arith operation
3185 CODE with TYPE0 for operand 0, and TYPE1 for operand 1.
3186 LOCATION is the location of the message. */
3188 void
3191 {
3195 {
3240 }
3244 }
3245 \f
3246 /* Subroutine of build_binary_op, used for comparison operations.
3247 See if the operands have both been converted from subword integer types
3248 and, if so, perhaps change them both back to their original type.
3249 This function is also responsible for converting the two operands
3250 to the proper common type for comparison.
3252 The arguments of this function are all pointers to local variables
3253 of build_binary_op: OP0_PTR is &OP0, OP1_PTR is &OP1,
3254 RESTYPE_PTR is &RESULT_TYPE and RESCODE_PTR is &RESULTCODE.
3256 If this function returns nonzero, it means that the comparison has
3257 a constant value. What this function returns is an expression for
3258 that value. */
3260 tree
3263 {
3264 tree type;
3272 /* Throw away any conversions to wider types
3273 already present in the operands. */
3278 /* Handle the case that OP0 does not *contain* a conversion
3279 but it *requires* conversion to FINAL_TYPE. */
3286 /* If one of the operands must be floated, we cannot optimize. */
3290 /* If first arg is constant, swap the args (changing operation
3291 so value is preserved), for canonicalization. Don't do this if
3292 the second arg is 0. */
3297 {
3314 {
3329 }
3331 }
3333 /* If comparing an integer against a constant more bits wide,
3334 maybe we can deduce a value of 1 or 0 independent of the data.
3335 Or else truncate the constant now
3336 rather than extend the variable at run time.
3338 This is only interesting if the constant is the wider arg.
3339 Also, it is not safe if the constant is unsigned and the
3340 variable arg is signed, since in this case the variable
3341 would be sign-extended and then regarded as unsigned.
3342 Our technique fails in this case because the lowest/highest
3343 possible unsigned results don't follow naturally from the
3344 lowest/highest possible values of the variable operand.
3345 For just EQ_EXPR and NE_EXPR there is another technique that
3346 could be used: see if the constant can be faithfully represented
3347 in the other operand's type, by truncating it and reextending it
3348 and see if that preserves the constant's value. */
3354 {
3357 /* 1 if comparison is nominally unsigned. */
3359 tree val;
3371 {
3372 /* Convert primop1 to target type, but do not introduce
3373 additional overflow. We know primop1 is an int_cst. */
3377 }
3379 {
3382 }
3385 {
3390 }
3391 else
3392 {
3397 }
3400 /* This used to be a switch, but Genix compiler can't handle that. */
3402 {
3405 }
3407 {
3410 }
3412 {
3417 }
3419 {
3424 }
3426 {
3431 }
3433 {
3438 }
3440 /* If primop0 was sign-extended and unsigned comparison specd,
3441 we did a signed comparison above using the signed type bounds.
3442 But the comparison we output must be unsigned.
3444 Also, for inequalities, VAL is no good; but if the signed
3445 comparison had *any* fixed result, it follows that the
3446 unsigned comparison just tests the sign in reverse
3447 (positive values are LE, negative ones GE).
3448 So we can generate an unsigned comparison
3449 against an extreme value of the signed type. */
3452 {
3455 {
3470 }
3472 }
3475 {
3480 }
3483 {
3484 /* Don't forget to evaluate PRIMOP0 if it has side effects. */
3488 }
3490 /* Value is not predetermined, but do the comparison
3491 in the type of the operand that is not constant.
3492 TYPE is already properly set. */
3493 }
3495 /* If either arg is decimal float and the other is float, find the
3496 proper common type to use for comparison. */
3507 /* If args' natural types are both narrower than nominal type
3508 and both extend in the same manner, compare them
3509 in the type of the wider arg.
3510 Otherwise must actually extend both to the nominal
3511 common type lest different ways of extending
3512 alter the result.
3513 (eg, (short)-1 == (unsigned short)-1 should be 0.) */
3518 {
3522 type);
3523 /* Make sure shorter operand is extended the right way
3524 to match the longer operand. */
3525 primop0
3528 primop0);
3529 primop1
3532 primop1);
3533 }
3534 else
3535 {
3536 /* Here we must do the comparison on the nominal type
3537 using the args exactly as we received them. */
3544 {
3547 {
3549 /* All unsigned values are >= 0, so we warn. However,
3550 if OP0 is a constant that is >= 0, the signedness of
3551 the comparison isn't an issue, so suppress the
3552 warning. */
3556 primop0))))
3566 primop0))))
3574 }
3577 {
3578 /* Don't forget to evaluate PRIMOP0 if it has side effects. */
3583 }
3584 }
3585 }
3593 }
3594 \f
3595 /* Return a tree for the sum or difference (RESULTCODE says which)
3596 of pointer PTROP and integer INTOP. */
3598 tree
3601 {
3604 /* The result is a pointer of the same type that is being added. */
3608 {
3612 }
3614 {
3618 }
3620 {
3624 }
3625 else
3628 /* We are manipulating pointer values, so we don't need to warn
3629 about relying on undefined signed overflow. We disable the
3630 warning here because we use integer types so fold won't know that
3631 they are really pointers. */
3634 /* If what we are about to multiply by the size of the elements
3635 contains a constant term, apply distributive law
3636 and multiply that constant term separately.
3637 This helps produce common subexpressions. */
3642 /* If the constant comes from pointer subtraction,
3643 skip this optimization--it would cause an error. */
3645 /* If the constant is unsigned, and smaller than the pointer size,
3646 then we must skip this optimization. This is because it could cause
3647 an overflow error if the constant is negative but INTOP is not. */
3651 {
3656 /* Convert both subexpression types to the type of intop,
3657 because weird cases involving pointer arithmetic
3658 can result in a sum or difference with different type args. */
3663 }
3665 /* Convert the integer argument to a type the same size as sizetype
3666 so the multiply won't overflow spuriously. */
3672 /* Replace the integer argument with a suitable product by the object size.
3673 Do this multiplication as signed, then convert to the appropriate type
3674 for the pointer operation and disregard an overflow that occured only
3675 because of the sign-extension change in the latter conversion. */
3676 {
3684 }
3686 /* Create the sum or difference. */
3695 }
3696 \f
3697 /* Wrap a C_MAYBE_CONST_EXPR around an expression that is fully folded
3698 and if NON_CONST is known not to be permitted in an evaluated part
3699 of a constant expression. */
3701 tree
3703 {
3707 /* This should never be called for C++. */
3711 /* The result of folding may have a NOP_EXPR to set TREE_NO_WARNING. */
3720 }
3722 /* Wrap a SAVE_EXPR around EXPR, if appropriate. Like save_expr, but
3723 for C folds the inside expression and wraps a C_MAYBE_CONST_EXPR
3724 around the SAVE_EXPR if needed so that c_fully_fold does not need
3725 to look inside SAVE_EXPRs. */
3727 tree
3729 {
3738 }
3740 /* Return whether EXPR is a declaration whose address can never be
3741 NULL. */
3743 bool
3745 {
3750 }
3752 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
3753 or for an `if' or `while' statement or ?..: exp. It should already
3754 have been validated to be of suitable type; otherwise, a bad
3755 diagnostic may result.
3757 The EXPR is located at LOCATION.
3759 This preparation consists of taking the ordinary
3760 representation of an expression expr and producing a valid tree
3761 boolean expression describing whether expr is nonzero. We could
3762 simply always do build_binary_op (NE_EXPR, expr, truthvalue_false_node, 1),
3763 but we optimize comparisons, &&, ||, and !.
3765 The resulting type should always be `truthvalue_type_node'. */
3767 tree
3769 {
3771 {
3813 ? truthvalue_true_node
3819 ? truthvalue_true_node
3824 /* Fall through. */
3827 {
3830 {
3831 /* Common Ada/Pascal programmer's mistake. */
3833 OPT_Waddress,
3835 inner);
3837 }
3839 }
3856 /* These don't change whether an object is nonzero or zero. */
3861 /* These don't change whether an object is zero or nonzero, but
3862 we can't ignore them if their second arg has side-effects. */
3864 {
3867 c_common_truthvalue_conversion
3870 }
3871 else
3876 /* Distribute the conversion into the arms of a COND_EXPR. */
3878 {
3888 }
3889 else
3890 {
3891 /* Folding will happen later for C. */
3899 }
3901 CASE_CONVERT:
3902 /* Don't cancel the effect of a CONVERT_EXPR from a REFERENCE_TYPE,
3903 since that affects how `default_conversion' will behave. */
3907 /* If this is widening the argument, we can ignore it. */
3917 {
3921 }
3926 }
3929 {
3931 expr = (build_binary_op
3935 c_common_truthvalue_conversion
3938 c_common_truthvalue_conversion
3943 }
3946 {
3951 }
3952 else
3955 ret:
3958 }
3959 \f
3968 /* Apply the TYPE_QUALS to the new DECL. */
3970 void
3972 {
3980 /* An object declared 'const' is only readonly after it is
3981 initialized. We don't have any way of expressing this currently,
3982 so we need to be conservative and unset TREE_READONLY for types
3983 with constructors. Otherwise aliasing code will ignore stores in
3984 an inline constructor. */
3988 {
3991 }
3993 {
3995 /* Allow 'restrict' on arrays of pointers.
3996 FIXME currently we just ignore it. */
4002 }
4003 }
4005 /* Hash function for the problem of multiple type definitions in
4006 different files. This must hash all types that will compare
4007 equal via comptypes to the same value. In practice it hashes
4008 on some of the simple stuff and leaves the details to comptypes. */
4010 static hashval_t
4012 {
4016 tree t2;
4018 {
4019 /* For pointers, hash on pointee type plus some swizzling. */
4022 /* Hash on number of elements and total size. */
4041 }
4043 i++;
4044 /* We might have a VLA here. */
4047 else
4050 }
4054 /* Return the typed-based alias set for T, which may be an expression
4055 or a type. Return -1 if we don't do anything special. */
4057 alias_set_type
4059 {
4060 tree u;
4063 /* For VLAs, use the alias set of the element type rather than the
4064 default of alias set 0 for types compared structurally. */
4066 {
4070 }
4072 /* Permit type-punning when accessing a union, provided the access
4073 is directly through the union. For example, this code does not
4074 permit taking the address of a union member and then storing
4075 through it. Even the type-punning allowed here is a GCC
4076 extension, albeit a common and useful one; the C standard says
4077 that such accesses have implementation-defined behavior. */
4085 /* That's all the expressions we handle specially. */
4089 /* The C standard guarantees that any object may be accessed via an
4090 lvalue that has character type. */
4096 /* The C standard specifically allows aliasing between signed and
4097 unsigned variants of the same type. We treat the signed
4098 variant as canonical. */
4100 {
4103 /* t1 == t can happen for boolean nodes which are always unsigned. */
4106 }
4108 /* Handle the case of multiple type nodes referring to "the same" type,
4109 which occurs with IMA. These share an alias set. FIXME: Currently only
4110 C90 is handled. (In C99 type compatibility is not transitive, which
4111 complicates things mightily. The alias set splay trees can theoretically
4112 represent this, but insertion is tricky when you consider all the
4113 different orders things might arrive in.) */
4118 /* Save time if there's only one input file. */
4122 /* Pointers need special handling if they point to any type that
4123 needs special handling (below). */
4125 {
4126 tree t2;
4127 /* Find bottom type under any nested POINTERs. */
4131 ;
4139 }
4140 /* These are the only cases that need special handling. */
4147 /* Undefined? */
4151 /* Look up t in hash table. Only one of the compatible types within each
4152 alias set is recorded in the table. */
4156 NULL);
4159 {
4162 }
4163 else
4164 /* Our caller will assign and record (in t) a new alias set; all we need
4165 to do is remember t in the hash table. */
4169 }
4170 \f
4171 /* Compute the value of 'sizeof (TYPE)' or '__alignof__ (TYPE)', where
4172 the second parameter indicates which OPERATOR is being applied.
4173 The COMPLAIN flag controls whether we should diagnose possibly
4174 ill-formed constructs or not. LOC is the location of the SIZEOF or
4175 TYPEOF operator. */
4177 tree
4180 {
4188 {
4190 {
4197 }
4198 else
4200 }
4202 {
4210 }
4212 {
4217 }
4218 else
4219 {
4221 /* Convert in case a char is more than one unit. */
4225 else
4227 }
4229 /* VALUE will have an integer type with TYPE_IS_SIZETYPE set.
4230 TYPE_IS_SIZETYPE means that certain things (like overflow) will
4231 never happen. However, this node should really have type
4232 `size_t', which is just a typedef for an ordinary integer type. */
4237 }
4239 /* Implement the __alignof keyword: Return the minimum required
4240 alignment of EXPR, measured in bytes. For VAR_DECLs,
4241 FUNCTION_DECLs and FIELD_DECLs return DECL_ALIGN (which can be set
4242 from an "aligned" __attribute__ specification). LOC is the
4243 location of the ALIGNOF operator. */
4245 tree
4247 {
4248 tree t;
4255 {
4258 }
4264 {
4271 {
4278 }
4280 }
4281 else
4285 }
4286 \f
4287 /* Handle C and C++ default attributes. */
4289 enum built_in_attribute
4290 {
4291 #define DEF_ATTR_NULL_TREE(ENUM) ENUM,
4292 #define DEF_ATTR_INT(ENUM, VALUE) ENUM,
4293 #define DEF_ATTR_IDENT(ENUM, STRING) ENUM,
4294 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) ENUM,
4296 #undef DEF_ATTR_NULL_TREE
4297 #undef DEF_ATTR_INT
4298 #undef DEF_ATTR_IDENT
4299 #undef DEF_ATTR_TREE_LIST
4300 ATTR_LAST
4301 };
4307 enum c_builtin_type
4308 {
4309 #define DEF_PRIMITIVE_TYPE(NAME, VALUE) NAME,
4310 #define DEF_FUNCTION_TYPE_0(NAME, RETURN) NAME,
4311 #define DEF_FUNCTION_TYPE_1(NAME, RETURN, ARG1) NAME,
4312 #define DEF_FUNCTION_TYPE_2(NAME, RETURN, ARG1, ARG2) NAME,
4313 #define DEF_FUNCTION_TYPE_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
4314 #define DEF_FUNCTION_TYPE_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
4315 #define DEF_FUNCTION_TYPE_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) NAME,
4316 #define DEF_FUNCTION_TYPE_6(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6) NAME,
4317 #define DEF_FUNCTION_TYPE_7(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7) NAME,
4318 #define DEF_FUNCTION_TYPE_VAR_0(NAME, RETURN) NAME,
4319 #define DEF_FUNCTION_TYPE_VAR_1(NAME, RETURN, ARG1) NAME,
4320 #define DEF_FUNCTION_TYPE_VAR_2(NAME, RETURN, ARG1, ARG2) NAME,
4321 #define DEF_FUNCTION_TYPE_VAR_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
4322 #define DEF_FUNCTION_TYPE_VAR_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
4323 #define DEF_FUNCTION_TYPE_VAR_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG6) \
4324 NAME,
4325 #define DEF_POINTER_TYPE(NAME, TYPE) NAME,
4327 #undef DEF_PRIMITIVE_TYPE
4328 #undef DEF_FUNCTION_TYPE_0
4329 #undef DEF_FUNCTION_TYPE_1
4330 #undef DEF_FUNCTION_TYPE_2
4331 #undef DEF_FUNCTION_TYPE_3
4332 #undef DEF_FUNCTION_TYPE_4
4333 #undef DEF_FUNCTION_TYPE_5
4334 #undef DEF_FUNCTION_TYPE_6
4335 #undef DEF_FUNCTION_TYPE_7
4336 #undef DEF_FUNCTION_TYPE_VAR_0
4337 #undef DEF_FUNCTION_TYPE_VAR_1
4338 #undef DEF_FUNCTION_TYPE_VAR_2
4339 #undef DEF_FUNCTION_TYPE_VAR_3
4340 #undef DEF_FUNCTION_TYPE_VAR_4
4341 #undef DEF_FUNCTION_TYPE_VAR_5
4342 #undef DEF_POINTER_TYPE
4343 BT_LAST
4344 };
4348 /* A temporary array for c_common_nodes_and_builtins. Used in
4349 communication with def_fn_type. */
4352 /* A helper function for c_common_nodes_and_builtins. Build function type
4353 for DEF with return type RET and N arguments. If VAR is true, then the
4354 function should be variadic after those N arguments.
4356 Takes special care not to ICE if any of the types involved are
4357 error_mark_node, which indicates that said type is not in fact available
4358 (see builtin_type_for_size). In which case the function type as a whole
4359 should be error_mark_node. */
4361 static void
4363 {
4370 {
4376 }
4388 egress:
4390 }
4392 /* Build builtin functions common to both C and C++ language
4393 frontends. */
4395 static void
4397 {
4398 #define DEF_PRIMITIVE_TYPE(ENUM, VALUE) \
4399 builtin_types[ENUM] = VALUE;
4400 #define DEF_FUNCTION_TYPE_0(ENUM, RETURN) \
4401 def_fn_type (ENUM, RETURN, 0, 0);
4402 #define DEF_FUNCTION_TYPE_1(ENUM, RETURN, ARG1) \
4403 def_fn_type (ENUM, RETURN, 0, 1, ARG1);
4404 #define DEF_FUNCTION_TYPE_2(ENUM, RETURN, ARG1, ARG2) \
4405 def_fn_type (ENUM, RETURN, 0, 2, ARG1, ARG2);
4406 #define DEF_FUNCTION_TYPE_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
4407 def_fn_type (ENUM, RETURN, 0, 3, ARG1, ARG2, ARG3);
4408 #define DEF_FUNCTION_TYPE_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
4409 def_fn_type (ENUM, RETURN, 0, 4, ARG1, ARG2, ARG3, ARG4);
4410 #define DEF_FUNCTION_TYPE_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
4411 def_fn_type (ENUM, RETURN, 0, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
4412 #define DEF_FUNCTION_TYPE_6(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
4413 ARG6) \
4414 def_fn_type (ENUM, RETURN, 0, 6, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6);
4415 #define DEF_FUNCTION_TYPE_7(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
4416 ARG6, ARG7) \
4417 def_fn_type (ENUM, RETURN, 0, 7, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7);
4418 #define DEF_FUNCTION_TYPE_VAR_0(ENUM, RETURN) \
4419 def_fn_type (ENUM, RETURN, 1, 0);
4420 #define DEF_FUNCTION_TYPE_VAR_1(ENUM, RETURN, ARG1) \
4421 def_fn_type (ENUM, RETURN, 1, 1, ARG1);
4422 #define DEF_FUNCTION_TYPE_VAR_2(ENUM, RETURN, ARG1, ARG2) \
4423 def_fn_type (ENUM, RETURN, 1, 2, ARG1, ARG2);
4424 #define DEF_FUNCTION_TYPE_VAR_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
4425 def_fn_type (ENUM, RETURN, 1, 3, ARG1, ARG2, ARG3);
4426 #define DEF_FUNCTION_TYPE_VAR_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
4427 def_fn_type (ENUM, RETURN, 1, 4, ARG1, ARG2, ARG3, ARG4);
4428 #define DEF_FUNCTION_TYPE_VAR_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
4429 def_fn_type (ENUM, RETURN, 1, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
4430 #define DEF_POINTER_TYPE(ENUM, TYPE) \
4431 builtin_types[(int) ENUM] = build_pointer_type (builtin_types[(int) TYPE]);
4435 #undef DEF_PRIMITIVE_TYPE
4436 #undef DEF_FUNCTION_TYPE_1
4437 #undef DEF_FUNCTION_TYPE_2
4438 #undef DEF_FUNCTION_TYPE_3
4439 #undef DEF_FUNCTION_TYPE_4
4440 #undef DEF_FUNCTION_TYPE_5
4441 #undef DEF_FUNCTION_TYPE_6
4442 #undef DEF_FUNCTION_TYPE_VAR_0
4443 #undef DEF_FUNCTION_TYPE_VAR_1
4444 #undef DEF_FUNCTION_TYPE_VAR_2
4445 #undef DEF_FUNCTION_TYPE_VAR_3
4446 #undef DEF_FUNCTION_TYPE_VAR_4
4447 #undef DEF_FUNCTION_TYPE_VAR_5
4448 #undef DEF_POINTER_TYPE
4453 #define DEF_BUILTIN(ENUM, NAME, CLASS, TYPE, LIBTYPE, BOTH_P, FALLBACK_P, \
4454 NONANSI_P, ATTRS, IMPLICIT, COND) \
4455 if (NAME && COND) \
4456 def_builtin_1 (ENUM, NAME, CLASS, \
4457 builtin_types[(int) TYPE], \
4458 builtin_types[(int) LIBTYPE], \
4459 BOTH_P, FALLBACK_P, NONANSI_P, \
4460 built_in_attributes[(int) ATTRS], IMPLICIT);
4462 #undef DEF_BUILTIN
4470 }
4472 /* Like get_identifier, but avoid warnings about null arguments when
4473 the argument may be NULL for targets where GCC lacks stdint.h type
4474 information. */
4478 {
4480 }
4482 /* Build tree nodes and builtin functions common to both C and C++ language
4483 frontends. */
4485 void
4487 {
4491 tree array_domain_type;
4492 tree va_list_ref_type_node;
4493 tree va_list_arg_type_node;
4495 /* Define `int' and `char' first so that dbx will output them first. */
4499 /* `signed' is the same as `int'. FIXME: the declarations of "signed",
4500 "unsigned long", "long long unsigned" and "unsigned short" were in C++
4501 but not C. Are the conditionals here needed? */
4507 long_unsigned_type_node);
4509 {
4511 int128_integer_type_node);
4513 int128_unsigned_type_node);
4514 }
4518 long_long_integer_type_node);
4520 long_long_unsigned_type_node);
4523 long_long_unsigned_type_node);
4526 short_unsigned_type_node);
4529 short_unsigned_type_node);
4531 /* Define both `signed char' and `unsigned char'. */
4535 /* These are types that c_common_type_for_size and
4536 c_common_type_for_mode use. */
4539 intQI_type_node));
4542 intHI_type_node));
4545 intSI_type_node));
4548 intDI_type_node));
4549 #if HOST_BITS_PER_WIDE_INT >= 64
4552 TYPE_DECL,
4554 intTI_type_node));
4555 #endif
4558 unsigned_intQI_type_node));
4561 unsigned_intHI_type_node));
4564 unsigned_intSI_type_node));
4567 unsigned_intDI_type_node));
4568 #if HOST_BITS_PER_WIDE_INT >= 64
4571 TYPE_DECL,
4573 unsigned_intTI_type_node));
4574 #endif
4576 /* Create the widest literal types. */
4577 widest_integer_literal_type_node
4581 widest_integer_literal_type_node));
4583 widest_unsigned_literal_type_node
4587 widest_unsigned_literal_type_node));
4589 /* `unsigned long' is the standard type for sizeof.
4590 Note that stddef.h uses `unsigned long',
4591 and this must agree, even if long and int are the same size. */
4592 size_type_node =
4597 pid_type_node =
4606 /* Only supported decimal floating point extension if the target
4607 actually supports underlying modes. */
4611 {
4615 }
4618 {
4623 long_long_fract_type_node);
4625 unsigned_short_fract_type_node);
4627 unsigned_fract_type_node);
4629 unsigned_long_fract_type_node);
4631 unsigned_long_long_fract_type_node);
4633 sat_short_fract_type_node);
4636 sat_long_fract_type_node);
4638 sat_long_long_fract_type_node);
4640 sat_unsigned_short_fract_type_node);
4642 sat_unsigned_fract_type_node);
4644 sat_unsigned_long_fract_type_node);
4646 sat_unsigned_long_long_fract_type_node);
4651 long_long_accum_type_node);
4653 unsigned_short_accum_type_node);
4655 unsigned_accum_type_node);
4657 unsigned_long_accum_type_node);
4659 unsigned_long_long_accum_type_node);
4661 sat_short_accum_type_node);
4664 sat_long_accum_type_node);
4666 sat_long_long_accum_type_node);
4668 sat_unsigned_short_accum_type_node);
4670 sat_unsigned_accum_type_node);
4672 sat_unsigned_long_accum_type_node);
4674 sat_unsigned_long_long_accum_type_node);
4676 }
4679 TYPE_DECL,
4681 complex_integer_type_node));
4683 TYPE_DECL,
4685 complex_float_type_node));
4687 TYPE_DECL,
4689 complex_double_type_node));
4693 complex_long_double_type_node));
4696 /* For C++, make fileptr_type_node a distinct void * type until
4697 FILE type is defined. */
4702 /* Set the TYPE_NAME for any variants that were built before
4703 record_builtin_type gave names to the built-in types. */
4704 {
4710 }
4712 /* This node must not be shared. */
4718 /* Make a type to be the domain of a few array types
4719 whose domains don't really matter.
4720 200 is small enough that it always fits in size_t
4721 and large enough that it can hold most function names for the
4722 initializations of __FUNCTION__ and __PRETTY_FUNCTION__. */
4725 /* Make a type for arrays of characters.
4726 With luck nothing will ever really depend on the length of this
4727 array type. */
4728 char_array_type_node
4731 /* Likewise for arrays of ints. */
4732 int_array_type_node
4736 const_string_type_node
4740 /* This is special for C++ so functions can be overloaded. */
4746 {
4749 else
4752 }
4754 /* This is for wide string constants. */
4755 wchar_array_type_node
4758 /* Define 'char16_t'. */
4763 {
4768 }
4770 /* This is for UTF-16 string constants. */
4771 char16_array_type_node
4774 /* Define 'char32_t'. */
4779 {
4784 }
4786 /* This is for UTF-32 string constants. */
4787 char32_array_type_node
4790 wint_type_node =
4793 intmax_type_node =
4795 uintmax_type_node =
4799 sig_atomic_type_node =
4802 int8_type_node =
4805 int16_type_node =
4808 int32_type_node =
4811 int64_type_node =
4814 uint8_type_node =
4817 uint16_type_node =
4820 c_uint32_type_node =
4823 c_uint64_type_node =
4826 int_least8_type_node =
4829 int_least16_type_node =
4832 int_least32_type_node =
4835 int_least64_type_node =
4838 uint_least8_type_node =
4841 uint_least16_type_node =
4844 uint_least32_type_node =
4847 uint_least64_type_node =
4850 int_fast8_type_node =
4853 int_fast16_type_node =
4856 int_fast32_type_node =
4859 int_fast64_type_node =
4862 uint_fast8_type_node =
4865 uint_fast16_type_node =
4868 uint_fast32_type_node =
4871 uint_fast64_type_node =
4874 intptr_type_node =
4877 uintptr_type_node =
4881 ptrdiff_type_node
4888 va_list_type_node));
4890 {
4893 tree ptype;
4896 {
4900 ptype));
4902 }
4903 }
4906 {
4909 }
4910 else
4911 {
4914 }
4921 /* Create the built-in __null node. It is important that this is
4922 not shared. */
4926 /* Since builtin_types isn't gc'ed, don't export these nodes. */
4928 }
4930 /* The number of named compound-literals generated thus far. */
4933 /* Set DECL_NAME for DECL, a VAR_DECL for a compound-literal. */
4935 void
4937 {
4940 compound_literal_number);
4941 compound_literal_number++;
4943 }
4945 tree
4947 {
4951 }
4954 /* Linked list of disabled built-in functions. */
4957 {
4965 /* Disable a built-in function specified by -fno-builtin-NAME. If NAME
4966 begins with "__builtin_", give an error. */
4968 void
4970 {
4973 else
4974 {
4979 }
4980 }
4983 /* Return true if the built-in function NAME has been disabled, false
4984 otherwise. */
4986 static bool
4988 {
4991 {
4994 }
4996 }
4999 /* Worker for DEF_BUILTIN.
5000 Possibly define a builtin function with one or two names.
5001 Does not declare a non-__builtin_ function if flag_no_builtin, or if
5002 nonansi_p and flag_no_nonansi_builtin. */
5004 static void
5011 {
5012 tree decl;
5025 fnattrs);
5035 }
5036 \f
5037 /* Nonzero if the type T promotes to int. This is (nearly) the
5038 integral promotions defined in ISO C99 6.3.1.1/2. */
5040 bool
5042 {
5044 {
5054 /* ??? Technically all enumerations not larger than an int
5055 promote to an int. But this is used along code paths
5056 that only want to notice a size change. */
5064 }
5065 }
5067 /* Return 1 if PARMS specifies a fixed number of parameters
5068 and none of their types is affected by default promotions. */
5070 int
5072 {
5073 const_tree t;
5075 {
5092 }
5094 }
5096 /* Recursively remove any '*' or '&' operator from TYPE. */
5097 tree
5099 {
5103 }
5105 /* Recursively remove pointer or array type from TYPE. */
5106 tree
5108 {
5112 }
5114 /* Used to compare case labels. K1 and K2 are actually tree nodes
5115 representing case labels, or NULL_TREE for a `default' label.
5116 Returns -1 if K1 is ordered before K2, -1 if K1 is ordered after
5117 K2, and 0 if K1 and K2 are equal. */
5119 int
5121 {
5122 /* Consider a NULL key (such as arises with a `default' label) to be
5123 smaller than anything else. */
5130 }
5132 /* Process a case label, located at LOC, for the range LOW_VALUE
5133 ... HIGH_VALUE. If LOW_VALUE and HIGH_VALUE are both NULL_TREE
5134 then this case label is actually a `default' label. If only
5135 HIGH_VALUE is NULL_TREE, then case label was declared using the
5136 usual C/C++ syntax, rather than the GNU case range extension.
5137 CASES is a tree containing all the case ranges processed so far;
5138 COND is the condition for the switch-statement itself. Returns the
5139 CASE_LABEL_EXPR created, or ERROR_MARK_NODE if no CASE_LABEL_EXPR
5140 is created. */
5142 tree
5145 {
5146 tree type;
5147 tree label;
5148 tree case_label;
5149 splay_tree_node node;
5151 /* Create the LABEL_DECL itself. */
5154 /* If there was an error processing the switch condition, bail now
5155 before we get more confused. */
5163 {
5166 }
5168 /* Case ranges are a GNU extension. */
5175 {
5180 }
5182 {
5187 }
5190 {
5191 /* If the LOW_VALUE and HIGH_VALUE are the same, then this isn't
5192 really a case range, even though it was written that way.
5193 Remove the HIGH_VALUE to simplify later processing. */
5198 }
5200 /* See if the case is in range of the type of the original testing
5201 expression. If both low_value and high_value are out of range,
5202 don't insert the case label and return NULL_TREE. */
5208 /* Look up the LOW_VALUE in the table of case labels we already
5209 have. */
5211 /* If there was not an exact match, check for overlapping ranges.
5212 There's no need to do this if there's no LOW_VALUE or HIGH_VALUE;
5213 that's a `default' label and the only overlap is an exact match. */
5215 {
5216 splay_tree_node low_bound;
5217 splay_tree_node high_bound;
5219 /* Even though there wasn't an exact match, there might be an
5220 overlap between this case range and another case range.
5221 Since we've (inductively) not allowed any overlapping case
5222 ranges, we simply need to find the greatest low case label
5223 that is smaller that LOW_VALUE, and the smallest low case
5224 label that is greater than LOW_VALUE. If there is an overlap
5225 it will occur in one of these two ranges. */
5231 /* Check to see if the LOW_BOUND overlaps. It is smaller than
5232 the LOW_VALUE, so there is no need to check unless the
5233 LOW_BOUND is in fact itself a case range. */
5239 /* Check to see if the HIGH_BOUND overlaps. The low end of that
5240 range is bigger than the low end of the current range, so we
5241 are only interested if the current range is a real range, and
5242 not an ordinary case label. */
5244 && high_value
5246 high_value)
5249 }
5250 /* If there was an overlap, issue an error. */
5252 {
5256 {
5260 }
5262 {
5265 }
5266 else
5267 {
5271 }
5273 }
5275 /* Add a CASE_LABEL to the statement-tree. */
5277 /* Register this case label in the splay tree. */
5284 error_out:
5285 /* Add a label so that the back-end doesn't think that the beginning of
5286 the switch is unreachable. Note that we do not add a case label, as
5287 that just leads to duplicates and thence to failure later on. */
5289 {
5292 }
5294 }
5296 /* Subroutines of c_do_switch_warnings, called via splay_tree_foreach.
5297 Used to verify that case values match up with enumerator values. */
5299 static void
5301 {
5304 /* ??? Not working too hard to print the double-word value.
5305 Should perhaps be done with %lwd in the diagnostic routines? */
5314 else
5323 buf);
5324 else
5329 }
5331 /* Subroutine of c_do_switch_warnings, called via splay_tree_foreach.
5332 Used to verify that case values match up with enumerator values. */
5334 static int
5336 {
5340 /* Skip default case. */
5344 /* If CASE_LOW_SEEN is not set, that means CASE_LOW did not appear
5345 when we did our enum->case scan. Reset our scratch bit after. */
5348 else
5351 /* If CASE_HIGH is non-null, we have a range. If CASE_HIGH_SEEN is
5352 not set, that means that CASE_HIGH did not appear when we did our
5353 enum->case scan. Reset our scratch bit after. */
5355 {
5358 else
5360 }
5363 }
5365 /* Handle -Wswitch*. Called from the front end after parsing the
5366 switch construct. */
5367 /* ??? Should probably be somewhere generic, since other languages
5368 besides C and C++ would want this. At the moment, however, C/C++
5369 are the only tree-ssa languages that support enumerations at all,
5370 so the point is moot. */
5372 void
5375 {
5376 splay_tree_node default_node;
5377 splay_tree_node node;
5378 tree chain;
5388 /* From here on, we only care about about enumerated types. */
5392 /* From here on, we only care about -Wswitch and -Wswitch-enum. */
5396 /* Check the cases. Warn about case values which are not members of
5397 the enumerated type. For -Wswitch-enum, or for -Wswitch when
5398 there is no default case, check that exactly all enumeration
5399 literals are covered by the cases. */
5401 /* Clearing COND if it is not an integer constant simplifies
5402 the tests inside the loop below. */
5406 /* The time complexity here is O(N*lg(N)) worst case, but for the
5407 common case of monotonically increasing enumerators, it is
5408 O(N), since the nature of the splay tree will keep the next
5409 element adjacent to the root at all times. */
5412 {
5418 {
5419 /* Mark the CASE_LOW part of the case entry as seen. */
5423 }
5425 /* Even though there wasn't an exact match, there might be a
5426 case range which includes the enumerator's value. */
5429 {
5433 {
5434 /* If we match the upper bound exactly, mark the CASE_HIGH
5435 part of the case entry as seen. */
5439 }
5440 }
5442 /* We've now determined that this enumerated literal isn't
5443 handled by the case labels of the switch statement. */
5445 /* If the switch expression is a constant, we only really care
5446 about whether that constant is handled by the switch. */
5450 /* If there is a default_node, the only relevant option is
5451 Wswitch-enum. Otherwise, if both are enabled then we prefer
5452 to warn using -Wswitch because -Wswitch is enabled by -Wall
5453 while -Wswitch-enum is explicit. */
5456 ? OPT_Wswitch_enum
5460 }
5462 /* Warn if there are case expressions that don't correspond to
5463 enumerators. This can occur since C and C++ don't enforce
5464 type-checking of assignments to enumeration variables.
5466 The time complexity here is now always O(N) worst case, since
5467 we should have marked both the lower bound and upper bound of
5468 every disjoint case label, with CASE_LOW_SEEN and CASE_HIGH_SEEN
5469 above. This scan also resets those fields. */
5472 }
5474 /* Finish an expression taking the address of LABEL (an
5475 IDENTIFIER_NODE). Returns an expression for the address.
5477 LOC is the location for the expression returned. */
5479 tree
5481 {
5482 tree result;
5492 else
5493 {
5496 /* The current function is not necessarily uninlinable.
5497 Computed gotos are incompatible with inlining, but the value
5498 here could be used only in a diagnostic, for example. */
5500 }
5503 }
5504 \f
5506 /* Given a boolean expression ARG, return a tree representing an increment
5507 or decrement (as indicated by CODE) of ARG. The front end must check for
5508 invalid cases (e.g., decrement in C++). */
5509 tree
5511 {
5512 tree val;
5517 {
5540 }
5543 }
5544 \f
5545 /* Built-in macros for stddef.h and stdint.h, that require macros
5546 defined in this file. */
5547 void
5549 {
5612 }
5614 static void
5616 {
5617 /* Fill in the built_in_attributes array. */
5618 #define DEF_ATTR_NULL_TREE(ENUM) \
5619 built_in_attributes[(int) ENUM] = NULL_TREE;
5620 #define DEF_ATTR_INT(ENUM, VALUE) \
5621 built_in_attributes[(int) ENUM] = build_int_cst (NULL_TREE, VALUE);
5622 #define DEF_ATTR_IDENT(ENUM, STRING) \
5623 built_in_attributes[(int) ENUM] = get_identifier (STRING);
5624 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) \
5625 built_in_attributes[(int) ENUM] \
5626 = tree_cons (built_in_attributes[(int) PURPOSE], \
5627 built_in_attributes[(int) VALUE], \
5628 built_in_attributes[(int) CHAIN]);
5630 #undef DEF_ATTR_NULL_TREE
5631 #undef DEF_ATTR_INT
5632 #undef DEF_ATTR_IDENT
5633 #undef DEF_ATTR_TREE_LIST
5634 }
5636 /* Returns TRUE iff the attribute indicated by ATTR_ID takes a plain
5637 identifier as an argument, so the front end shouldn't look it up. */
5639 bool
5641 {
5646 else
5648 }
5650 /* Attribute handlers common to C front ends. */
5652 /* Handle a "packed" attribute; arguments as in
5653 struct attribute_spec.handler. */
5655 static tree
5658 {
5660 {
5664 }
5666 {
5668 /* Still pack bitfields. */
5673 else
5675 }
5676 /* We can't set DECL_PACKED for a VAR_DECL, because the bit is
5677 used for DECL_REGISTER. It wouldn't mean anything anyway.
5678 We can't set DECL_PACKED on the type of a TYPE_DECL, because
5679 that changes what the typedef is typing. */
5680 else
5681 {
5684 }
5687 }
5689 /* Handle a "nocommon" attribute; arguments as in
5690 struct attribute_spec.handler. */
5692 static tree
5696 {
5699 else
5700 {
5703 }
5706 }
5708 /* Handle a "common" attribute; arguments as in
5709 struct attribute_spec.handler. */
5711 static tree
5714 {
5717 else
5718 {
5721 }
5724 }
5726 /* Handle a "noreturn" attribute; arguments as in
5727 struct attribute_spec.handler. */
5729 static tree
5732 {
5735 /* See FIXME comment in c_common_attribute_table. */
5741 = build_pointer_type
5744 else
5745 {
5748 }
5751 }
5753 /* Handle a "hot" and attribute; arguments as in
5754 struct attribute_spec.handler. */
5756 static tree
5759 {
5761 {
5763 {
5767 }
5768 /* Most of the rest of the hot processing is done later with
5769 lookup_attribute. */
5770 }
5771 else
5772 {
5775 }
5778 }
5779 /* Handle a "cold" and attribute; arguments as in
5780 struct attribute_spec.handler. */
5782 static tree
5785 {
5787 {
5789 {
5793 }
5794 /* Most of the rest of the cold processing is done later with
5795 lookup_attribute. */
5796 }
5797 else
5798 {
5801 }
5804 }
5806 /* Handle a "noinline" attribute; arguments as in
5807 struct attribute_spec.handler. */
5809 static tree
5813 {
5816 else
5817 {
5820 }
5823 }
5825 /* Handle a "noclone" attribute; arguments as in
5826 struct attribute_spec.handler. */
5828 static tree
5832 {
5834 {
5837 }
5840 }
5842 /* Handle a "always_inline" attribute; arguments as in
5843 struct attribute_spec.handler. */
5845 static tree
5850 {
5852 {
5853 /* Set the attribute and mark it for disregarding inline
5854 limits. */
5856 }
5857 else
5858 {
5861 }
5864 }
5866 /* Handle a "gnu_inline" attribute; arguments as in
5867 struct attribute_spec.handler. */
5869 static tree
5874 {
5876 {
5877 /* Do nothing else, just set the attribute. We'll get at
5878 it later with lookup_attribute. */
5879 }
5880 else
5881 {
5884 }
5887 }
5889 /* Handle a "leaf" attribute; arguments as in
5890 struct attribute_spec.handler. */
5892 static tree
5896 {
5898 {
5901 }
5903 {
5906 }
5909 }
5911 /* Handle an "artificial" attribute; arguments as in
5912 struct attribute_spec.handler. */
5914 static tree
5919 {
5921 {
5922 /* Do nothing else, just set the attribute. We'll get at
5923 it later with lookup_attribute. */
5924 }
5925 else
5926 {
5929 }
5932 }
5934 /* Handle a "flatten" attribute; arguments as in
5935 struct attribute_spec.handler. */
5937 static tree
5939 tree args ATTRIBUTE_UNUSED,
5941 {
5943 /* Do nothing else, just set the attribute. We'll get at
5944 it later with lookup_attribute. */
5945 ;
5946 else
5947 {
5950 }
5953 }
5955 /* Handle a "warning" or "error" attribute; arguments as in
5956 struct attribute_spec.handler. */
5958 static tree
5961 {
5964 /* Do nothing else, just set the attribute. We'll get at
5965 it later with lookup_attribute. */
5966 ;
5967 else
5968 {
5971 }
5974 }
5976 /* Handle a "used" attribute; arguments as in
5977 struct attribute_spec.handler. */
5979 static tree
5982 {
5987 {
5992 }
5993 else
5994 {
5997 }
6000 }
6002 /* Handle a "unused" attribute; arguments as in
6003 struct attribute_spec.handler. */
6005 static tree
6008 {
6010 {
6018 {
6023 }
6024 else
6025 {
6028 }
6029 }
6030 else
6031 {
6035 }
6038 }
6040 /* Handle a "externally_visible" attribute; arguments as in
6041 struct attribute_spec.handler. */
6043 static tree
6048 {
6052 {
6055 {
6059 }
6060 }
6061 else
6062 {
6065 }
6068 }
6070 /* Handle a "const" attribute; arguments as in
6071 struct attribute_spec.handler. */
6073 static tree
6076 {
6079 /* See FIXME comment on noreturn in c_common_attribute_table. */
6085 = build_pointer_type
6088 else
6089 {
6092 }
6095 }
6097 /* Handle a "transparent_union" attribute; arguments as in
6098 struct attribute_spec.handler. */
6100 static tree
6104 {
6105 tree type;
6114 {
6115 /* When IN_PLACE is set, leave the check for FIELDS and MODE to
6116 the code in finish_struct. */
6118 {
6123 /* A type variant isn't good enough, since we don't a cast
6124 to such a type removed as a no-op. */
6126 }
6130 }
6132 ignored:
6135 }
6137 /* Subroutine of handle_{con,de}structor_attribute. Evaluate ARGS to
6138 get the requested priority for a constructor or destructor,
6139 possibly issuing diagnostics for invalid or reserved
6140 priorities. */
6142 static priority_type
6144 {
6145 HOST_WIDE_INT pri;
6146 tree arg;
6152 {
6155 else
6158 }
6170 {
6173 "destructor priorities from 0 to %d are reserved "
6175 MAX_RESERVED_INIT_PRIORITY);
6176 else
6178 "constructor priorities from 0 to %d are reserved "
6180 MAX_RESERVED_INIT_PRIORITY);
6181 }
6184 invalid:
6187 MAX_INIT_PRIORITY);
6188 else
6190 MAX_INIT_PRIORITY);
6192 }
6194 /* Handle a "constructor" attribute; arguments as in
6195 struct attribute_spec.handler. */
6197 static tree
6201 {
6208 {
6209 priority_type priority;
6214 }
6215 else
6216 {
6219 }
6222 }
6224 /* Handle a "destructor" attribute; arguments as in
6225 struct attribute_spec.handler. */
6227 static tree
6231 {
6238 {
6239 priority_type priority;
6244 }
6245 else
6246 {
6249 }
6252 }
6254 /* Nonzero if the mode is a valid vector mode for this architecture.
6255 This returns nonzero even if there is no hardware support for the
6256 vector mode, but we can emulate with narrower modes. */
6258 static int
6260 {
6264 /* Doh! What's going on? */
6273 /* Hardware support. Woo hoo! */
6279 /* We should probably return 1 if requesting V4DI and we have no DI,
6280 but we have V2DI, but this is probably very unlikely. */
6282 /* If we have support for the inner mode, we can safely emulate it.
6283 We may not have V2DI, but me can emulate with a pair of DIs. */
6285 }
6288 /* Handle a "mode" attribute; arguments as in
6289 struct attribute_spec.handler. */
6291 static tree
6294 {
6302 else
6303 {
6308 tree typefm;
6313 {
6319 }
6321 /* Change this type to have a type with the specified mode.
6322 First check for the special modes. */
6335 else
6338 {
6341 }
6344 {
6347 }
6351 {
6383 }
6385 {
6388 }
6391 {
6396 {
6399 }
6403 else
6406 }
6407 else
6408 {
6409 /* For fixed-point modes, we need to test if the signness of type
6410 and the machine mode are consistent. */
6413 {
6416 }
6417 /* For fixed-point modes, we need to pass saturating info. */
6421 }
6424 {
6427 }
6429 {
6430 /* For enumeral types, copy the precision from the integer
6431 type returned above. If not an INTEGER_TYPE, we can't use
6432 this mode for this type. */
6434 {
6437 }
6440 {
6443 }
6444 else
6445 {
6446 /* We cannot build a type variant, as there's code that assumes
6447 that TYPE_MAIN_VARIANT has the same mode. This includes the
6448 debug generators. Instead, create a subrange type. This
6449 results in all of the enumeral values being emitted only once
6450 in the original, and the subtype gets them by reference. */
6453 else
6456 }
6457 }
6461 {
6464 }
6467 }
6470 }
6472 /* Handle a "section" attribute; arguments as in
6473 struct attribute_spec.handler. */
6475 static tree
6478 {
6482 {
6488 {
6492 {
6494 "section attribute cannot be specified for "
6497 }
6499 /* The decl may have already been given a section attribute
6500 from a previous declaration. Ensure they match. */
6504 {
6508 }
6512 {
6515 }
6516 else
6518 }
6519 else
6520 {
6523 }
6524 }
6525 else
6526 {
6530 }
6533 }
6535 /* Handle a "aligned" attribute; arguments as in
6536 struct attribute_spec.handler. */
6538 static tree
6541 {
6550 {
6554 }
6559 {
6562 }
6564 {
6567 }
6569 {
6572 }
6574 {
6577 /* If we have a TYPE_DECL, then copy the type, so that we
6578 don't accidentally modify a builtin type. See pushdecl. */
6581 {
6588 }
6589 else
6594 }
6597 {
6600 }
6603 {
6608 else
6612 }
6613 else
6614 {
6617 }
6620 }
6622 /* Handle a "weak" attribute; arguments as in
6623 struct attribute_spec.handler. */
6625 static tree
6630 {
6633 {
6636 }
6638 {
6642 }
6646 else
6650 }
6652 /* Handle an "alias" or "ifunc" attribute; arguments as in
6653 struct attribute_spec.handler, except that IS_ALIAS tells us
6654 whether this is an alias as opposed to ifunc attribute. */
6656 static tree
6659 {
6664 {
6667 }
6671 /* A static variable declaration is always a tentative definition,
6672 but the alias is a non-tentative definition which overrides. */
6675 {
6679 }
6683 {
6687 }
6689 /* Note that the very first time we process a nested declaration,
6690 decl_function_context will not be set. Indeed, *would* never
6691 be set except for the DECL_INITIAL/DECL_EXTERNAL frobbery that
6692 we do below. After such frobbery, pushdecl would set the context.
6693 In any case, this is never what we want. */
6695 {
6696 tree id;
6700 {
6704 }
6706 /* This counts as a use of the object pointed to. */
6711 else
6712 {
6715 else
6718 }
6721 /* ifuncs are also aliases, so set that attribute too. */
6724 }
6725 else
6726 {
6729 }
6732 }
6734 /* Handle an "alias" or "ifunc" attribute; arguments as in
6735 struct attribute_spec.handler. */
6737 static tree
6740 {
6742 }
6744 /* Handle an "alias" or "ifunc" attribute; arguments as in
6745 struct attribute_spec.handler. */
6747 static tree
6750 {
6752 }
6754 /* Handle a "weakref" attribute; arguments as in struct
6755 attribute_spec.handler. */
6757 static tree
6760 {
6763 /* We must ignore the attribute when it is associated with
6764 local-scoped decls, since attribute alias is ignored and many
6765 such symbols do not even have a DECL_WEAK field. */
6767 || current_function_decl
6769 {
6773 }
6776 {
6780 }
6782 /* The idea here is that `weakref("name")' mutates into `weakref,
6783 alias("name")', and weakref without arguments, in turn,
6784 implicitly adds weak. */
6787 {
6794 }
6795 else
6796 {
6801 /* Can't call declare_weak because it wants this to be TREE_PUBLIC,
6802 and that isn't supported; and because it wants to add it to
6803 the list of weak decls, which isn't helpful. */
6805 }
6808 }
6810 /* Handle an "visibility" attribute; arguments as in
6811 struct attribute_spec.handler. */
6813 static tree
6817 {
6823 {
6827 {
6829 name);
6831 }
6833 {
6837 }
6838 }
6840 {
6843 }
6846 {
6849 }
6851 /* If this is a type, set the visibility on the type decl. */
6853 {
6858 {
6860 name);
6862 }
6863 }
6873 else
6874 {
6875 error ("visibility argument must be one of \"default\", \"hidden\", \"protected\" or \"internal\"");
6877 }
6881 {
6895 }
6900 /* Go ahead and attach the attribute to the node as well. This is needed
6901 so we can determine whether we have VISIBILITY_DEFAULT because the
6902 visibility was not specified, or because it was explicitly overridden
6903 from the containing scope. */
6906 }
6908 /* Determine the ELF symbol visibility for DECL, which is either a
6909 variable or a function. It is an error to use this function if a
6910 definition of DECL is not available in this translation unit.
6911 Returns true if the final visibility has been determined by this
6912 function; false if the caller is free to make additional
6913 modifications. */
6915 bool
6917 {
6921 /* If the user explicitly specified the visibility with an
6922 attribute, honor that. DECL_VISIBILITY will have been set during
6923 the processing of the attribute. We check for an explicit
6924 attribute, rather than just checking DECL_VISIBILITY_SPECIFIED,
6925 to distinguish the use of an attribute from the use of a "#pragma
6926 GCC visibility push(...)"; in the latter case we still want other
6927 considerations to be able to overrule the #pragma. */
6929 || (TARGET_DLLIMPORT_DECL_ATTRIBUTES
6934 /* Set default visibility to whatever the user supplied with
6935 visibility_specified depending on #pragma GCC visibility. */
6937 {
6940 {
6943 /* If visibility changed and DECL already has DECL_RTL, ensure
6944 symbol flags are updated. */
6949 }
6950 }
6952 }
6954 /* Handle an "tls_model" attribute; arguments as in
6955 struct attribute_spec.handler. */
6957 static tree
6960 {
6961 tree id;
6968 {
6971 }
6976 {
6979 }
6989 else
6990 error ("tls_model argument must be one of \"local-exec\", \"initial-exec\", \"local-dynamic\" or \"global-dynamic\"");
6994 }
6996 /* Handle a "no_instrument_function" attribute; arguments as in
6997 struct attribute_spec.handler. */
6999 static tree
7004 {
7008 {
7012 }
7014 {
7018 }
7019 else
7023 }
7025 /* Handle a "malloc" attribute; arguments as in
7026 struct attribute_spec.handler. */
7028 static tree
7031 {
7035 else
7036 {
7039 }
7042 }
7044 /* Handle a "alloc_size" attribute; arguments as in
7045 struct attribute_spec.handler. */
7047 static tree
7050 {
7053 {
7060 {
7065 }
7066 }
7068 }
7070 /* Handle a "fn spec" attribute; arguments as in
7071 struct attribute_spec.handler. */
7073 static tree
7077 {
7082 }
7084 /* Handle a "returns_twice" attribute; arguments as in
7085 struct attribute_spec.handler. */
7087 static tree
7090 {
7093 else
7094 {
7097 }
7100 }
7102 /* Handle a "no_limit_stack" attribute; arguments as in
7103 struct attribute_spec.handler. */
7105 static tree
7110 {
7114 {
7118 }
7120 {
7124 }
7125 else
7129 }
7131 /* Handle a "pure" attribute; arguments as in
7132 struct attribute_spec.handler. */
7134 static tree
7137 {
7140 /* ??? TODO: Support types. */
7141 else
7142 {
7145 }
7148 }
7150 /* Handle a "no vops" attribute; arguments as in
7151 struct attribute_spec.handler. */
7153 static tree
7157 {
7161 }
7163 /* Handle a "deprecated" attribute; arguments as in
7164 struct attribute_spec.handler. */
7166 static tree
7170 {
7178 {
7181 }
7184 {
7194 else
7196 }
7198 {
7203 }
7204 else
7208 {
7211 {
7217 }
7220 else
7222 }
7225 }
7227 /* Handle a "vector_size" attribute; arguments as in
7228 struct attribute_spec.handler. */
7230 static tree
7234 {
7244 {
7247 }
7249 /* Get the vector size (in bytes). */
7252 /* We need to provide for vector pointers, vector arrays, and
7253 functions returning vectors. For example:
7255 __attribute__((vector_size(16))) short *foo;
7257 In this case, the mode is SI, but the type being modified is
7258 HI, so we need to look further. */
7267 /* Get the mode of the type being modified. */
7278 {
7281 }
7284 {
7287 }
7290 {
7293 }
7295 /* Calculate how many units fit in the vector. */
7298 {
7301 }
7305 /* Build back pointers if needed. */
7309 }
7311 /* Handle the "nonnull" attribute. */
7312 static tree
7316 {
7320 /* If no arguments are specified, all pointer arguments should be
7321 non-null. Verify a full prototype is given so that the arguments
7322 will have the correct types when we actually check them later. */
7324 {
7326 {
7329 }
7331 }
7333 /* Argument list specified. Verify that each argument number references
7334 a pointer argument. */
7336 {
7337 tree argument;
7341 {
7346 }
7350 {
7352 {
7356 }
7360 {
7365 }
7368 {
7373 }
7374 }
7375 }
7378 }
7380 /* Check the argument list of a function call for null in argument slots
7381 that are marked as requiring a non-null pointer argument. The NARGS
7382 arguments are passed in the array ARGARRAY.
7383 */
7385 static void
7387 {
7392 {
7394 {
7397 /* Walk the argument list. If we encounter an argument number we
7398 should check for non-null, do it. If the attribute has no args,
7399 then every pointer argument is checked (in which case the check
7400 for pointer type is done in check_nonnull_arg). */
7402 {
7407 }
7408 }
7409 }
7410 }
7412 /* Check that the Nth argument of a function call (counting backwards
7413 from the end) is a (pointer)0. The NARGS arguments are passed in the
7414 array ARGARRAY. */
7416 static void
7418 {
7422 {
7425 tree sentinel;
7427 /* Skip over the named arguments. */
7429 {
7431 len++;
7432 }
7435 {
7438 }
7440 /* The sentinel must be one of the varargs, i.e.
7441 in position >= the number of fixed arguments. */
7443 {
7447 }
7449 /* Validate the sentinel. */
7453 /* Although __null (in C++) is only an integer we allow it
7454 nevertheless, as we are guaranteed that it's exactly
7455 as wide as a pointer, and we don't want to force
7456 users to cast the NULL they have written there.
7457 We warn with -Wstrict-null-sentinel, though. */
7460 }
7461 }
7463 /* Helper for check_function_nonnull; given a list of operands which
7464 must be non-null in ARGS, determine if operand PARAM_NUM should be
7465 checked. */
7467 static bool
7469 {
7473 {
7480 }
7482 }
7484 /* Check that the function argument PARAM (which is operand number
7485 PARAM_NUM) is non-null. This is called by check_function_nonnull
7486 via check_function_arguments_recurse. */
7488 static void
7491 {
7492 /* Just skip checking the argument if it's not a pointer. This can
7493 happen if the "nonnull" attribute was given without an operand
7494 list (which means to check every pointer argument). */
7502 }
7504 /* Helper for nonnull attribute handling; fetch the operand number
7505 from the attribute argument list. */
7507 static bool
7509 {
7510 /* Verify the arg number is a constant. */
7517 }
7519 /* Handle a "nothrow" attribute; arguments as in
7520 struct attribute_spec.handler. */
7522 static tree
7525 {
7528 /* ??? TODO: Support types. */
7529 else
7530 {
7533 }
7536 }
7538 /* Handle a "cleanup" attribute; arguments as in
7539 struct attribute_spec.handler. */
7541 static tree
7544 {
7548 /* ??? Could perhaps support cleanups on TREE_STATIC, much like we do
7549 for global destructors in C++. This requires infrastructure that
7550 we don't have generically at the moment. It's also not a feature
7551 we'd be missing too much, since we do have attribute constructor. */
7553 {
7557 }
7559 /* Verify that the argument is a function in scope. */
7560 /* ??? We could support pointers to functions here as well, if
7561 that was considered desirable. */
7564 {
7568 }
7571 {
7575 }
7577 /* That the function has proper type is checked with the
7578 eventual call to build_function_call. */
7581 }
7583 /* Handle a "warn_unused_result" attribute. No special handling. */
7585 static tree
7589 {
7590 /* Ignore the attribute for functions not returning any value. */
7592 {
7595 }
7598 }
7600 /* Handle a "sentinel" attribute. */
7602 static tree
7605 {
7609 {
7613 }
7614 else
7615 {
7620 {
7624 }
7625 }
7628 {
7632 {
7636 }
7637 else
7638 {
7640 {
7644 }
7645 }
7646 }
7649 }
7651 /* Handle a "type_generic" attribute. */
7653 static tree
7657 {
7658 tree params;
7660 /* Ensure we have a function type. */
7667 /* Ensure we have a variadic function. */
7671 }
7673 /* Handle a "target" attribute. */
7675 static tree
7678 {
7679 /* Ensure we have a function type. */
7681 {
7684 }
7686 flags))
7690 }
7692 /* Arguments being collected for optimization. */
7699 /* Inner function to convert a TREE_LIST to argv string to parse the optimize
7700 options in ARGS. ATTR_P is true if this is for attribute(optimize), and
7701 false for #pragma GCC optimize. */
7703 bool
7705 {
7713 tree ap;
7715 /* Build up argv vector. Just in case the string is stored away, use garbage
7716 collected strings. */
7721 {
7725 {
7729 }
7732 {
7733 /* Split string into multiple substrings. */
7741 {
7748 {
7752 }
7753 else
7754 {
7757 }
7761 /* If the user supplied -Oxxx or -fxxx, only allow -Oxxx or -fxxx
7762 options. */
7764 {
7769 else
7773 }
7776 {
7779 /* Assume that Ox is -Ox, a numeric value is -Ox, a s by
7780 itself is -Os, and any other switch begins with a -f. */
7786 }
7791 }
7793 }
7794 }
7804 /* Now parse the options. */
7813 /* Don't allow changing -fstrict-aliasing. */
7818 }
7820 /* For handling "optimize" attribute. arguments as in
7821 struct attribute_spec.handler. */
7823 static tree
7826 {
7827 /* Ensure we have a function type. */
7829 {
7832 }
7833 else
7834 {
7838 /* Save current options. */
7841 /* If we previously had some optimization options, use them as the
7842 default. */
7847 /* Parse options, and update the vector. */
7852 /* Restore current options. */
7854 }
7857 }
7859 /* Handle a "no_split_stack" attribute. */
7861 static tree
7866 {
7870 {
7874 }
7876 {
7880 }
7883 }
7884 \f
7885 /* Check for valid arguments being passed to a function.
7886 ATTRS is a list of attributes. There are NARGS arguments in the array
7887 ARGARRAY. TYPELIST is the list of argument types for the function.
7888 */
7889 void
7891 {
7892 /* Check for null being passed in a pointer argument that must be
7893 non-null. We also need to do this if format checking is enabled. */
7898 /* Check for errors in format strings. */
7905 }
7907 /* Generic argument checking recursion routine. PARAM is the argument to
7908 be checked. PARAM_NUM is the number of the argument. CALLBACK is invoked
7909 once the argument is resolved. CTX is context for the callback. */
7910 void
7915 {
7919 {
7920 /* Strip coercion. */
7924 }
7927 {
7929 tree attrs;
7932 /* See if this is a call to a known internationalization function
7933 that modifies a format arg. Such a function may have multiple
7934 format_arg attributes (for example, ngettext). */
7937 attrs;
7940 {
7941 tree inner_arg;
7942 tree format_num_expr;
7945 call_expr_arg_iterator iter;
7947 /* Extract the argument number, which was previously checked
7948 to be valid. */
7960 {
7965 }
7966 }
7968 /* If we found a format_arg attribute and did a recursive check,
7969 we are done with checking this argument. Otherwise, we continue
7970 and this will be considered a non-literal. */
7973 }
7976 {
7977 /* Check both halves of the conditional expression. */
7983 }
7986 }
7988 /* Checks for a builtin function FNDECL that the number of arguments
7989 NARGS against the required number REQUIRED and issues an error if
7990 there is a mismatch. Returns true if the number of arguments is
7991 correct, otherwise false. */
7993 static bool
7995 {
7997 {
8001 }
8003 {
8007 }
8009 }
8011 /* Verifies the NARGS arguments ARGS to the builtin function FNDECL.
8012 Returns false if there was an error, otherwise true. */
8014 bool
8016 {
8022 {
8032 {
8034 {
8038 }
8040 }
8050 {
8057 {
8061 }
8063 }
8068 {
8073 {
8077 }
8080 {
8082 fndecl);
8084 }
8086 }
8091 }
8092 }
8094 /* Function to help qsort sort FIELD_DECLs by name order. */
8096 int
8098 {
8103 /* A nontype is "greater" than a type. */
8112 }
8115 gt_pointer_operator new_value;
8119 /* This routine compares two fields like field_decl_cmp but using the
8120 pointer operator in resort_data. */
8122 static int
8124 {
8129 /* A nontype is "greater" than a type. */
8135 {
8142 }
8144 }
8146 /* Resort DECL_SORTED_FIELDS because pointers have been reordered. */
8148 void
8151 gt_pointer_operator new_value,
8153 {
8158 resort_field_decl_cmp);
8159 }
8161 /* Subroutine of c_parse_error.
8162 Return the result of concatenating LHS and RHS. RHS is really
8163 a string literal, its first character is indicated by RHS_START and
8164 RHS_SIZE is its length (including the terminating NUL character).
8166 The caller is responsible for deleting the returned pointer. */
8170 {
8176 }
8178 /* Issue the error given by GMSGID, indicating that it occurred before
8179 TOKEN, which had the associated VALUE. */
8181 void
8184 {
8185 #define catenate_messages(M1, M2) catenate_strings ((M1), (M2), sizeof (M2))
8195 {
8200 {
8213 }
8217 else
8223 }
8233 {
8238 }
8244 {
8249 }
8250 else
8254 {
8257 }
8258 #undef catenate_messages
8259 }
8261 /* Mapping for cpp message reasons to the options that enable them. */
8263 struct reason_option_codes_t
8264 {
8267 };
8286 };
8288 /* Return the gcc option code associated with the reason for a cpp
8289 message, or 0 if none. */
8291 static int
8293 {
8297 {
8300 }
8302 }
8304 /* Callback from cpp_error for PFILE to print diagnostics from the
8305 preprocessor. The diagnostic is of type LEVEL, with REASON set
8306 to the reason code if LEVEL is represents a warning, at location
8307 LOCATION unless this is after lexing and the compiler's location
8308 should be used instead, with column number possibly overridden by
8309 COLUMN_OVERRIDE if not zero; MSG is the translated message and AP
8310 the arguments. Returns true if a diagnostic was emitted, false
8311 otherwise. */
8313 bool
8317 {
8318 diagnostic_info diagnostic;
8319 diagnostic_t dlevel;
8324 {
8329 /* Fall through. */
8354 }
8367 }
8369 /* Convert a character from the host to the target execution character
8370 set. cpplib handles this, mostly. */
8372 HOST_WIDE_INT
8374 {
8375 /* Character constants in GCC proper are sign-extended under -fsigned-char,
8376 zero-extended under -fno-signed-char. cpplib insists that characters
8377 and character constants are always unsigned. Hence we must convert
8378 back and forth. */
8386 else
8388 }
8390 /* Build the result of __builtin_offsetof. EXPR is a nested sequence of
8391 component references, with STOP_REF, or alternatively an INDIRECT_REF of
8392 NULL, at the bottom; much like the traditional rendering of offsetof as a
8393 macro. Returns the folded and properly cast result. */
8395 static tree
8397 {
8405 {
8421 {
8424 }
8434 {
8438 }
8452 {
8455 }
8459 /* Check if the offset goes beyond the upper bound of the array. */
8461 {
8467 {
8471 {
8472 tree v;
8479 {
8487 }
8488 /* Don't warn if the array might be considered a poor
8489 man's flexible array member with a very permissive
8490 definition thereof. */
8494 "index %E denotes an offset "
8497 }
8498 }
8499 }
8503 /* Handle static members of volatile structs. */
8510 }
8513 }
8515 tree
8517 {
8518 /* Convert back from the internal sizetype to size_t. */
8520 }
8522 /* Warn for A ?: C expressions (with B omitted) where A is a boolean
8523 expression, because B will always be true. */
8525 void
8527 {
8530 "the omitted middle operand in ?: will always be %<true%>, "
8532 }
8534 /* Print an error message for an invalid lvalue. USE says
8535 how the lvalue is being used and so selects the error message. */
8537 void
8539 {
8541 {
8559 }
8560 }
8561 \f
8562 /* *PTYPE is an incomplete array. Complete it with a domain based on
8563 INITIAL_VALUE. If INITIAL_VALUE is not present, use 1 if DO_DEFAULT
8564 is true. Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
8565 2 if INITIAL_VALUE was NULL, and 3 if INITIAL_VALUE was empty. */
8567 int
8569 {
8576 {
8578 {
8579 int eltsize
8582 }
8584 {
8588 {
8592 }
8593 else
8594 {
8595 tree curindex;
8608 cnt++)
8609 {
8613 else
8614 {
8618 size_one_node);
8619 }
8622 }
8625 }
8626 }
8627 else
8628 {
8629 /* Make an error message unless that happened already. */
8632 }
8633 }
8634 else
8635 {
8639 }
8646 else
8649 /* Using build_distinct_type_copy and modifying things afterward instead
8650 of using build_array_type to create a new type preserves all of the
8651 TYPE_LANG_FLAG_? bits that the front end may have set. */
8657 /* Make sure we have the canonical MAIN_TYPE. */
8660 hashcode);
8663 /* Fix the canonical type. */
8673 else
8678 else
8684 {
8686 /* If we proceed with the array type as it is, we'll eventually
8687 crash in tree_low_cst(). */
8689 }
8693 }
8695 \f
8696 /* Used to help initialize the builtin-types.def table. When a type of
8697 the correct size doesn't exist, use error_mark_node instead of NULL.
8698 The later results in segfaults even when a decl using the type doesn't
8699 get invoked. */
8701 tree
8703 {
8706 }
8708 /* A helper function for resolve_overloaded_builtin in resolving the
8709 overloaded __sync_ builtins. Returns a positive power of 2 if the
8710 first operand of PARAMS is a pointer to a supported data type.
8711 Returns 0 if an error is encountered. */
8713 static int
8715 {
8716 tree type;
8720 {
8723 }
8737 incompatible:
8740 }
8742 /* A helper function for resolve_overloaded_builtin. Adds casts to
8743 PARAMS to make arguments match up with those of FUNCTION. Drops
8744 the variadic arguments at the end. Returns false if some error
8745 was encountered; true on success. */
8747 static bool
8749 {
8751 tree ptype;
8754 /* We've declared the implementation functions to use "volatile void *"
8755 as the pointer parameter, so we shouldn't get any complaints from the
8756 call to check_function_arguments what ever type the user used. */
8760 /* For the rest of the values, we need to cast these to FTYPE, so that we
8761 don't get warnings for passing pointer types, etc. */
8764 {
8765 tree val;
8769 {
8772 }
8774 /* ??? Ideally for the first conversion we'd use convert_for_assignment
8775 so that we get warnings for anything that doesn't match the pointer
8776 type. This isn't portable across the C and C++ front ends atm. */
8783 }
8785 /* The definition of these primitives is variadic, with the remaining
8786 being "an optional list of variables protected by the memory barrier".
8787 No clue what that's supposed to mean, precisely, but we consider all
8788 call-clobbered variables to be protected so we're safe. */
8792 }
8794 /* A helper function for resolve_overloaded_builtin. Adds a cast to
8795 RESULT to make it match the type of the first pointer argument in
8796 PARAMS. */
8798 static tree
8800 {
8804 }
8806 /* Some builtin functions are placeholders for other expressions. This
8807 function should be called immediately after parsing the call expression
8808 before surrounding code has committed to the type of the expression.
8810 LOC is the location of the builtin call.
8812 FUNCTION is the DECL that has been invoked; it is known to be a builtin.
8813 PARAMS is the argument list for the call. The return value is non-null
8814 when expansion is complete, and null if normal processing should
8815 continue. */
8817 tree
8819 {
8822 {
8828 else
8832 }
8834 /* Handle BUILT_IN_NORMAL here. */
8836 {
8853 {
8871 }
8875 }
8876 }
8878 /* Ignoring their sign, return true if two scalar types are the same. */
8879 bool
8881 {
8888 /* Equality works here because c_common_signed_type uses
8889 TYPE_MAIN_VARIANT. */
8892 }
8894 /* Check for missing format attributes on function pointers. LTYPE is
8895 the new type or left-hand side type. RTYPE is the old type or
8896 right-hand side type. Returns TRUE if LTYPE is missing the desired
8897 attribute. */
8899 bool
8901 {
8903 tree ra;
8909 {
8910 tree la;
8915 }
8916 else
8918 }
8920 /* Subscripting with type char is likely to lose on a machine where
8921 chars are signed. So warn on any machine, but optionally. Don't
8922 warn for unsigned char since that type is safe. Don't warn for
8923 signed char because anyone who uses that must have done so
8924 deliberately. Furthermore, we reduce the false positive load by
8925 warning only for non-constant value of type char. */
8927 void
8929 {
8933 }
8935 /* Implement -Wparentheses for the unexpected C precedence rules, to
8936 cover cases like x + y << z which readers are likely to
8937 misinterpret. We have seen an expression in which CODE is a binary
8938 operator used to combine expressions ARG_LEFT and ARG_RIGHT, which
8939 before folding had CODE_LEFT and CODE_RIGHT. CODE_LEFT and
8940 CODE_RIGHT may be ERROR_MARK, which means that that side of the
8941 expression was not formed using a binary or unary operator, or it
8942 was enclosed in parentheses. */
8944 void
8948 {
8952 /* This macro tests that the expression ARG with original tree code
8953 CODE appears to be a boolean expression. or the result of folding a
8954 boolean expression. */
8955 #define APPEARS_TO_BE_BOOLEAN_EXPR_P(CODE, ARG) \
8956 (truth_value_p (TREE_CODE (ARG)) \
8957 || TREE_CODE (TREE_TYPE (ARG)) == BOOLEAN_TYPE \
8959 || ((CODE) != INTEGER_CST \
8960 && (integer_onep (ARG) || integer_zerop (ARG))))
8963 {
8995 /* Check cases like x|y==z */
9000 /* Check cases like !x | y */
9014 /* Check cases like x^y==z */
9028 /* Check cases like x&y==z */
9033 /* Check cases like !x & y */
9064 }
9065 #undef NOT_A_BOOLEAN_EXPR_P
9066 }
9068 /* If LABEL (a LABEL_DECL) has not been used, issue a warning. */
9070 void
9072 {
9074 {
9077 else
9079 }
9080 }
9082 #ifndef TARGET_HAS_TARGETCM
9084 #endif
9086 /* Warn for division by zero according to the value of DIVISOR. LOC
9087 is the location of the division operator. */
9089 void
9091 {
9092 /* If DIVISOR is zero, and has integral or fixed-point type, issue a warning
9093 about division by zero. Do not issue a warning if DIVISOR has a
9094 floating-point type, since we consider 0.0/0.0 a valid way of
9095 generating a NaN. */
9099 }
9101 /* Subroutine of build_binary_op. Give warnings for comparisons
9102 between signed and unsigned quantities that may fail. Do the
9103 checking based on the original operand trees ORIG_OP0 and ORIG_OP1,
9104 so that casts will be considered, but default promotions won't
9105 be.
9107 LOCATION is the location of the comparison operator.
9109 The arguments of this function map directly to local variables
9110 of build_binary_op. */
9112 void
9117 {
9122 /* In C++, check for comparison of different enum types. */
9128 {
9132 }
9134 /* Do not warn if the comparison is being done in a signed type,
9135 since the signed type will only be chosen if it can represent
9136 all the values of the unsigned type. */
9139 /* Do not warn if both operands are unsigned. */
9142 else
9143 {
9149 else
9157 /* Do not warn if the signed quantity is an unsuffixed integer
9158 literal (or some static constant expression involving such
9159 literals or a conditional expression involving such literals)
9160 and it is non-negative. */
9163 /* Do not warn if the comparison is an equality operation, the
9164 unsigned quantity is an integral constant, and it would fit
9165 in the result if the result were signed. */
9170 /* In C, do not warn if the unsigned quantity is an enumeration
9171 constant and its maximum value would fit in the result if the
9172 result were signed. */
9178 else
9180 OPT_Wsign_compare,
9182 }
9184 /* Warn if two unsigned values are being compared in a size larger
9185 than their original size, and one (and only one) is the result of
9186 a `~' operator. This comparison will always fail.
9188 Also warn if one operand is a constant, and the constant does not
9189 have all bits set that are set in the ~ operand when it is
9190 extended. */
9197 {
9204 {
9205 tree primop;
9211 {
9215 }
9216 else
9217 {
9221 }
9226 {
9229 {
9233 else
9236 }
9237 }
9238 }
9246 }
9247 }
9249 /* RESULT_TYPE is the result of converting TYPE1 and TYPE2 to a common
9250 type via c_common_type. If -Wdouble-promotion is in use, and the
9251 conditions for warning have been met, issue a warning. GMSGID is
9252 the warning message. It must have two %T specifiers for the type
9253 that was converted (generally "float") and the type to which it was
9254 converted (generally "double), respectively. LOC is the location
9255 to which the awrning should refer. */
9257 void
9260 {
9261 tree source_type;
9265 /* If the conversion will not occur at run-time, there is no need to
9266 warn about it. */
9278 else
9281 }
9283 /* Setup a TYPE_DECL node as a typedef representation.
9285 X is a TYPE_DECL for a typedef statement. Create a brand new
9286 ..._TYPE node (which will be just a variant of the existing
9287 ..._TYPE node with identical properties) and then install X
9288 as the TYPE_NAME of this brand new (duplicate) ..._TYPE node.
9290 The whole point here is to end up with a situation where each
9291 and every ..._TYPE node the compiler creates will be uniquely
9292 associated with AT MOST one node representing a typedef name.
9293 This way, even though the compiler substitutes corresponding
9294 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
9295 early on, later parts of the compiler can always do the reverse
9296 translation and get back the corresponding typedef name. For
9297 example, given:
9299 typedef struct S MY_TYPE;
9300 MY_TYPE object;
9302 Later parts of the compiler might only know that `object' was of
9303 type `struct S' if it were not for code just below. With this
9304 code however, later parts of the compiler see something like:
9306 struct S' == struct S
9307 typedef struct S' MY_TYPE;
9308 struct S' object;
9310 And they can then deduce (from the node for type struct S') that
9311 the original object declaration was:
9313 MY_TYPE object;
9315 Being able to do this is important for proper support of protoize,
9316 and also for generating precise symbolic debugging information
9317 which takes full account of the programmer's (typedef) vocabulary.
9319 Obviously, we don't want to generate a duplicate ..._TYPE node if
9320 the TYPE_DECL node that we are now processing really represents a
9321 standard built-in type. */
9323 void
9325 {
9329 {
9332 }
9335 {
9343 }
9344 }
9346 /* Record the types used by the current global variable declaration
9347 being parsed, so that we can decide later to emit their debug info.
9348 Those types are in types_used_by_cur_var_decl, and we are going to
9349 store them in the types_used_by_vars_hash hash table.
9350 DECL is the declaration of the global variable that has been parsed. */
9352 void
9354 {
9358 {
9361 }
9362 }
9364 /* The C and C++ parsers both use vectors to hold function arguments.
9365 For efficiency, we keep a cache of unused vectors. This is the
9366 cache. */
9373 /* Return a new vector from the cache. If the cache is empty,
9374 allocate a new vector. These vectors are GC'ed, so it is OK if the
9375 pointer is not released.. */
9379 {
9382 else
9383 {
9384 /* Passing 0 to VEC_alloc returns NULL, and our callers require
9385 that we always return a non-NULL value. The vector code uses
9386 4 when growing a NULL vector, so we do too. */
9388 }
9389 }
9391 /* Release a vector of trees back to the cache. */
9393 void
9395 {
9397 {
9400 }
9401 }
9403 /* Get a new tree vector holding a single tree. */
9407 {
9411 }
9413 /* Get a new tree vector which is a copy of an existing one. */
9417 {
9420 tree t;
9427 }