| blob | dbef4b314eab6045fd700dd631edc98bd0b0d5f1 |
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, 2011
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/>. */
52 /* The following symbols are subsumed in the c_global_trees array, and
53 listed here individually for documentation purposes.
55 INTEGER_TYPE and REAL_TYPE nodes for the standard data types.
57 tree short_integer_type_node;
58 tree long_integer_type_node;
59 tree long_long_integer_type_node;
60 tree int128_integer_type_node;
62 tree short_unsigned_type_node;
63 tree long_unsigned_type_node;
64 tree long_long_unsigned_type_node;
65 tree int128_unsigned_type_node;
67 tree truthvalue_type_node;
68 tree truthvalue_false_node;
69 tree truthvalue_true_node;
71 tree ptrdiff_type_node;
73 tree unsigned_char_type_node;
74 tree signed_char_type_node;
75 tree wchar_type_node;
77 tree char16_type_node;
78 tree char32_type_node;
80 tree float_type_node;
81 tree double_type_node;
82 tree long_double_type_node;
84 tree complex_integer_type_node;
85 tree complex_float_type_node;
86 tree complex_double_type_node;
87 tree complex_long_double_type_node;
89 tree dfloat32_type_node;
90 tree dfloat64_type_node;
91 tree_dfloat128_type_node;
93 tree intQI_type_node;
94 tree intHI_type_node;
95 tree intSI_type_node;
96 tree intDI_type_node;
97 tree intTI_type_node;
99 tree unsigned_intQI_type_node;
100 tree unsigned_intHI_type_node;
101 tree unsigned_intSI_type_node;
102 tree unsigned_intDI_type_node;
103 tree unsigned_intTI_type_node;
105 tree widest_integer_literal_type_node;
106 tree widest_unsigned_literal_type_node;
108 Nodes for types `void *' and `const void *'.
110 tree ptr_type_node, const_ptr_type_node;
112 Nodes for types `char *' and `const char *'.
114 tree string_type_node, const_string_type_node;
116 Type `char[SOMENUMBER]'.
117 Used when an array of char is needed and the size is irrelevant.
119 tree char_array_type_node;
121 Type `int[SOMENUMBER]' or something like it.
122 Used when an array of int needed and the size is irrelevant.
124 tree int_array_type_node;
126 Type `wchar_t[SOMENUMBER]' or something like it.
127 Used when a wide string literal is created.
129 tree wchar_array_type_node;
131 Type `char16_t[SOMENUMBER]' or something like it.
132 Used when a UTF-16 string literal is created.
134 tree char16_array_type_node;
136 Type `char32_t[SOMENUMBER]' or something like it.
137 Used when a UTF-32 string literal is created.
139 tree char32_array_type_node;
141 Type `int ()' -- used for implicit declaration of functions.
143 tree default_function_type;
145 A VOID_TYPE node, packaged in a TREE_LIST.
147 tree void_list_node;
149 The lazily created VAR_DECLs for __FUNCTION__, __PRETTY_FUNCTION__,
150 and __func__. (C doesn't generate __FUNCTION__ and__PRETTY_FUNCTION__
151 VAR_DECLS, but C++ does.)
153 tree function_name_decl_node;
154 tree pretty_function_name_decl_node;
155 tree c99_function_name_decl_node;
157 Stack of nested function name VAR_DECLs.
159 tree saved_function_name_decls;
161 */
164 \f
165 /* Switches common to the C front ends. */
167 /* Nonzero means don't output line number information. */
171 /* Nonzero causes -E output not to be done, but directives such as
172 #define that have side effects are still obeyed. */
176 /* Nonzero means dump macros in some fashion. */
180 /* Nonzero means pass #include lines through to the output. */
184 /* Nonzero means process PCH files while preprocessing. */
188 /* The file name to which we should write a precompiled header, or
189 NULL if no header will be written in this compile. */
193 /* Nonzero if an ISO standard was selected. It rejects macros in the
194 user's namespace. */
197 /* Warn about #pragma directives that are not recognized. */
201 /* Warn about format/argument anomalies in calls to formatted I/O functions
202 (*printf, *scanf, strftime, strfmon, etc.). */
206 /* C/ObjC language option variables. */
209 /* Nonzero means allow type mismatches in conditional expressions;
210 just make their values `void'. */
214 /* Nonzero means enable C89 Amendment 1 features. */
218 /* Nonzero means use the ISO C99 (or C1X) dialect of C. */
222 /* Nonzero means use the ISO C1X dialect of C. */
226 /* Nonzero means that we have builtin functions, and main is an int. */
231 /* ObjC language option variables. */
234 /* Tells the compiler that this is a special run. Do not perform any
235 compiling, instead we are to test some platform dependent features
236 and output a C header file with appropriate definitions. */
240 /* Tells the compiler what is the constant string class for ObjC. */
245 /* C++ language option variables. */
248 /* Nonzero means generate separate instantiation control files and
249 juggle them at link time. */
253 /* The C++ dialect being used. C++98 is the default. */
257 /* Maximum template instantiation depth. This limit exists to limit the
258 time it takes to notice excessively recursive template instantiations;
259 the default value of 1024 is likely to be in the next C++ standard. */
263 /* The elements of `ridpointers' are identifier nodes for the reserved
264 type names and storage classes. It is indexed by a RID_... value. */
269 /* Nonzero means don't warn about problems that occur when the code is
270 executed. */
273 /* Whether we are building a boolean conversion inside
274 convert_for_assignment, or some other late binary operation. If
275 build_binary_op is called for C (from code shared by C and C++) in
276 this case, then the operands have already been folded and the
277 result will not be folded again, so C_MAYBE_CONST_EXPR should not
278 be generated. */
281 /* Whether lexing has been completed, so subsequent preprocessor
282 errors should use the compiler's input_location. */
285 /* Information about how a function name is generated. */
286 struct fname_var_t
287 {
291 };
293 /* The three ways of getting then name of the current function. */
296 {
297 /* C99 compliant __func__, must be first. */
299 /* GCC __FUNCTION__ compliant. */
301 /* GCC __PRETTY_FUNCTION__ compliant. */
304 };
306 /* Global visibility options. */
380 /* Reserved words. The third field is a mask: keywords are disabled
381 if they match the mask.
383 Masks for languages:
384 C --std=c89: D_C99 | D_CXXONLY | D_OBJC | D_CXX_OBJC
385 C --std=c99: D_CXXONLY | D_OBJC
386 ObjC is like C except that D_OBJC and D_CXX_OBJC are not set
387 C++ --std=c98: D_CONLY | D_CXXOX | D_OBJC
388 C++ --std=c0x: D_CONLY | D_OBJC
389 ObjC++ is like C++ except that D_OBJC is not set
391 If -fno-asm is used, D_ASM is added to the mask. If
392 -fno-gnu-keywords is used, D_EXT is added. If -fno-asm and C in
393 C89 mode, D_EXT89 is added for both -fno-asm and -fno-gnu-keywords.
394 In C with -Wc++-compat, we warn if D_CXXWARN is set.
396 Note the complication of the D_CXX_OBJC keywords. These are
397 reserved words such as 'class'. In C++, 'class' is a reserved
398 word. In Objective-C++ it is too. In Objective-C, it is a
399 reserved word too, but only if it follows an '@' sign.
400 */
402 {
544 /* These Objective-C keywords are recognized only immediately after
545 an '@'. */
562 /* These are recognized only in protocol-qualifier context
563 (see above) */
570 /* These are recognized inside a property attribute list */
579 };
584 /* Table of machine-independent attributes common to all C-like languages. */
586 {
587 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler,
588 affects_type_identity } */
595 /* FIXME: logically, noreturn attributes should be listed as
596 "false, true, true" and apply to function types. But implementing this
597 would require all the places in the compiler that use TREE_THIS_VOLATILE
598 on a decl to identify non-returning functions to be located and fixed
599 to check the function type instead. */
624 /* The same comments as for noreturn attributes apply to const ones. */
648 handle_no_instrument_function_attribute,
658 /* For internal use (marking of builtins) only. The name contains space
659 to prevent its usage in source code. */
681 /* For internal use (marking of builtins) only. The name contains space
682 to prevent its usage in source code. */
701 /* For internal use (marking of builtins and runtime functions) only.
702 The name contains space to prevent its usage in source code. */
706 };
708 /* Give the specifications for the format attributes, used by C and all
709 descendants. */
712 {
713 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler,
714 affects_type_identity } */
720 };
722 /* Return identifier for address space AS. */
726 {
730 }
732 /* Push current bindings for the function name VAR_DECLS. */
734 void
736 {
741 {
745 {
747 saved);
749 }
750 }
752 /* Normally they'll have been NULL, so only push if we've got a
753 stack, or they are non-NULL. */
755 saved_function_name_decls);
756 }
758 /* Finish up the current bindings, adding them into the current function's
759 statement tree. This must be done _before_ finish_stmt_tree is called.
760 If there is no current function, we must be at file scope and no statements
761 are involved. Pop the previous bindings. */
763 void
765 {
774 {
782 }
788 {
789 /* We had saved values, restore them. */
790 tree saved;
793 {
798 }
800 }
802 }
804 /* Return the text name of the current function, suitably prettified
805 by PRETTY_P. Return string must be freed by caller. */
809 {
816 {
819 }
832 {
835 }
838 }
840 /* Return the VAR_DECL for a const char array naming the current
841 function. If the VAR_DECL has not yet been created, create it
842 now. RID indicates how it should be formatted and IDENTIFIER_NODE
843 ID is its name (unfortunately C and C++ hold the RID values of
844 keywords in different places, so we can't derive RID from ID in
845 this language independent code. LOC is the location of the
846 function. */
848 tree
850 {
860 {
861 /* If a tree is built here, it would normally have the lineno of
862 the current statement. Later this tree will be moved to the
863 beginning of the function and this line number will be wrong.
864 To avoid this problem set the lineno to 0 here; that prevents
865 it from appearing in the RTL. */
866 tree stmts;
874 saved_function_name_decls
878 }
883 }
885 /* Given a STRING_CST, give it a suitable array-of-chars data type. */
887 tree
889 {
894 /* Compute the number of elements, for the array type. */
896 {
899 }
901 {
904 }
906 {
909 }
910 else
911 {
914 }
916 /* C89 2.2.4.1, C99 5.2.4.1 (Translation limits). The analogous
917 limit in C++98 Annex B is very large (65536) and is not normative,
918 so we do not diagnose it (warn_overlength_strings is forced off
919 in c_common_post_options). */
921 {
925 /* Translators: The %d after 'ISO C' will be 90 or 99. Do not
926 separate the %d from the 'C'. 'ISO' should not be
927 translated, but it may be moved after 'C%d' in languages
928 where modifiers follow nouns. */
930 "string length %qd is greater than the length %qd "
933 }
935 /* Create the array type for the string constant. The ISO C++
936 standard says that a string literal has type `const char[N]' or
937 `const wchar_t[N]'. We use the same logic when invoked as a C
938 front-end with -Wwrite-strings.
939 ??? We should change the type of an expression depending on the
940 state of a warning flag. We should just be warning -- see how
941 this is handled in the C++ front-end for the deprecated implicit
942 conversion from string literals to `char*' or `wchar_t*'.
944 The C++ front end relies on TYPE_MAIN_VARIANT of a cv-qualified
945 array type being the unqualified version of that type.
946 Therefore, if we are constructing an array of const char, we must
947 construct the matching unqualified array type first. The C front
948 end does not require this, but it does no harm, so we do it
949 unconditionally. */
960 }
961 \f
962 /* Fully fold EXPR, an expression that was not folded (beyond integer
963 constant expressions and null pointer constants) when being built
964 up. If IN_INIT, this is in a static initializer and certain
965 changes are made to the folding done. Clear *MAYBE_CONST if
966 MAYBE_CONST is not NULL and EXPR is definitely not a constant
967 expression because it contains an evaluated operator (in C99) or an
968 operator outside of sizeof returning an integer constant (in C90)
969 not permitted in constant expressions, or because it contains an
970 evaluated arithmetic overflow. (*MAYBE_CONST should typically be
971 set to true by callers before calling this function.) Return the
972 folded expression. Function arguments have already been folded
973 before calling this function, as have the contents of SAVE_EXPR,
974 TARGET_EXPR, BIND_EXPR, VA_ARG_EXPR, OBJ_TYPE_REF and
975 C_MAYBE_CONST_EXPR. */
977 tree
979 {
980 tree ret;
986 /* This function is not relevant to C++ because C++ folds while
987 parsing, and may need changes to be correct for C++ when C++
988 stops folding while parsing. */
995 {
998 }
1005 }
1007 /* Internal helper for c_fully_fold. EXPR and IN_INIT are as for
1008 c_fully_fold. *MAYBE_CONST_OPERANDS is cleared because of operands
1009 not permitted, while *MAYBE_CONST_ITSELF is cleared because of
1010 arithmetic overflow (for C90, *MAYBE_CONST_OPERANDS is carried from
1011 both evaluated and unevaluated subexpressions while
1012 *MAYBE_CONST_ITSELF is carried from only evaluated
1013 subexpressions). */
1015 static tree
1018 {
1030 /* This function is not relevant to C++ because C++ folds while
1031 parsing, and may need changes to be correct for C++ when C++
1032 stops folding while parsing. */
1036 /* Constants, declarations, statements, errors, SAVE_EXPRs and
1037 anything else not counted as an expression cannot usefully be
1038 folded further at this point. */
1044 /* Operands of variable-length expressions (function calls) have
1045 already been folded, as have __builtin_* function calls, and such
1046 expressions cannot occur in constant expressions. */
1048 {
1052 }
1055 {
1064 else
1067 }
1069 /* Assignment, increment, decrement, function call and comma
1070 operators, and statement expressions, cannot occur in constant
1071 expressions if evaluated / outside of sizeof. (Function calls
1072 were handled above, though VA_ARG_EXPR is treated like a function
1073 call here, and statement expressions are handled through
1074 C_MAYBE_CONST_EXPR to avoid folding inside them.) */
1076 {
1096 }
1098 /* Fold individual tree codes as appropriate. */
1100 {
1102 /* Any non-constancy will have been marked in a containing
1103 C_MAYBE_CONST_EXPR; there is no more folding to do here. */
1111 maybe_const_itself);
1116 {
1119 }
1128 maybe_const_itself);
1131 maybe_const_itself);
1137 {
1141 }
1183 /* Binary operations evaluating both arguments (increment and
1184 decrement are binary internally in GCC). */
1188 maybe_const_itself);
1196 /* The RHS of a MODIFY_EXPR was fully folded when building that
1197 expression for the sake of conversion warnings. */
1200 maybe_const_itself);
1204 ret = in_init
1207 else
1218 CASE_CONVERT:
1228 /* Unary operations. */
1231 maybe_const_itself);
1236 ret = in_init
1239 else
1244 {
1248 }
1250 {
1253 CASE_CONVERT:
1254 /* Don't warn about explicit conversions. We will already
1255 have warned about suspect implicit conversions. */
1262 }
1267 /* Binary operations not necessarily evaluating both
1268 arguments. */
1275 ? truthvalue_false_node
1283 ret = in_init
1286 else
1291 && op0_const
1292 && op0_const_self
1298 && op0_const_self
1324 else
1329 && op0_const
1330 && op0_const_self
1334 && op0_const_self
1338 && op0_const
1339 && op0_const_self
1343 && op0_const_self
1349 /* Each case where an operand with excess precision may be
1350 encountered must remove the EXCESS_PRECISION_EXPR around
1351 inner operands and possibly put one around the whole
1352 expression or possibly convert to the semantic type (which
1353 c_fully_fold does); we cannot tell at this stage which is
1354 appropriate in any particular case. */
1358 /* Various codes may appear through folding built-in functions
1359 and their arguments. */
1361 }
1363 out:
1364 /* Some folding may introduce NON_LVALUE_EXPRs; all lvalue checks
1365 have been done by this point, so remove them again. */
1369 {
1373 }
1377 }
1379 /* If not optimizing, EXP is not a VAR_DECL, or EXP has array type,
1380 return EXP. Otherwise, return either EXP or its known constant
1381 value (if it has one), but return EXP if EXP has mode BLKmode. ???
1382 Is the BLKmode test appropriate? */
1384 tree
1386 {
1387 tree ret;
1389 /* This function is only used by C, for c_fully_fold and other
1390 optimization, and may not be correct for C++. */
1401 /* Avoid unwanted tree sharing between the initializer and current
1402 function's body where the tree can be modified e.g. by the
1403 gimplifier. */
1407 }
1409 /* Print a warning if a constant expression had overflow in folding.
1410 Invoke this function on every expression that the language
1411 requires to be a constant expression.
1412 Note the ANSI C standard says it is erroneous for a
1413 constant expression to overflow. */
1415 void
1417 {
1425 }
1427 /* The same as above but print an unconditional error. */
1428 void
1430 {
1437 }
1439 /* Print a warning if an expression had overflow in folding and its
1440 operands hadn't.
1442 Invoke this function on every expression that
1443 (1) appears in the source code, and
1444 (2) is a constant expression that overflowed, and
1445 (3) is not already checked by convert_and_check;
1446 however, do not invoke this function on operands of explicit casts
1447 or when the expression is the result of an operator and any operand
1448 already overflowed. */
1450 void
1452 {
1457 {
1486 }
1487 }
1489 /* Warn about uses of logical || / && operator in a context where it
1490 is likely that the bitwise equivalent was intended by the
1491 programmer. We have seen an expression in which CODE is a binary
1492 operator used to combine expressions OP_LEFT and OP_RIGHT, which before folding
1493 had CODE_LEFT and CODE_RIGHT, into an expression of type TYPE. */
1494 void
1498 {
1510 /* Warn if &&/|| are being used in a context where it is
1511 likely that the bitwise equivalent was intended by the
1512 programmer. That is, an expression such as op && MASK
1513 where op should not be any boolean expression, nor a
1514 constant, and mask seems to be a non-boolean integer constant. */
1522 {
1526 else
1531 }
1533 /* We do not warn for constants because they are typical of macro
1534 expansions that test for features. */
1538 /* This warning only makes sense with logical operands. */
1554 /* If this is an OR operation, invert both sides; we will invert
1555 again at the end. */
1559 /* If both expressions are the same, if we can merge the ranges, and we
1560 can build the range test, return it or it inverted. */
1566 {
1572 "logical %<or%> "
1574 else
1576 "logical %<and%> "
1578 }
1579 }
1582 /* Print a warning about casts that might indicate violation
1583 of strict aliasing rules if -Wstrict-aliasing is used and
1584 strict aliasing mode is in effect. OTYPE is the original
1585 TREE_TYPE of EXPR, and TYPE the type we're casting to. */
1587 bool
1589 {
1590 /* Strip pointer conversion chains and get to the correct original type. */
1598 /* If the type we are casting to is a ref-all pointer
1599 dereferencing it is always valid. */
1606 {
1607 /* Casting the address of an object to non void pointer. Warn
1608 if the cast breaks type based aliasing. */
1610 {
1614 }
1615 else
1616 {
1617 /* warn_strict_aliasing >= 3. This includes the default (3).
1618 Only warn if the cast is dereferenced immediately. */
1619 alias_set_type set1 =
1625 {
1629 }
1632 {
1636 }
1637 }
1638 }
1639 else
1641 {
1642 /* At this level, warn for any conversions, even if an address is
1643 not taken in the same statement. This will likely produce many
1644 false positives, but could be useful to pinpoint problems that
1645 are not revealed at higher levels. */
1650 {
1654 }
1655 }
1658 }
1660 /* Warn for unlikely, improbable, or stupid DECL declarations
1661 of `main'. */
1663 void
1665 {
1666 function_args_iterator iter;
1667 tree type;
1671 {
1672 /* XXX void_type_node belies the abstraction. */
1678 {
1700 "third argument of %q+D should probably be "
1703 }
1704 }
1706 /* It is intentional that this message does not mention the third
1707 argument because it's only mentioned in an appendix of the
1708 standard. */
1712 }
1714 /* True if pointers to distinct types T1 and T2 can be converted to
1715 each other without an explicit cast. Only returns true for opaque
1716 vector types. */
1717 bool
1719 {
1726 }
1728 /* True if vector types T1 and T2 can be converted to each other
1729 without an explicit cast. If EMIT_LAX_NOTE is true, and T1 and T2
1730 can only be converted with -flax-vector-conversions yet that is not
1731 in effect, emit a note telling the user about that option if such
1732 a note has not previously been emitted. */
1733 bool
1735 {
1743 convertible_lax =
1758 {
1761 "conversions between vectors with differing "
1763 }
1766 }
1768 /* Like tree.c:get_narrower, but retain conversion from C++0x scoped enum
1769 to integral type. */
1771 static tree
1773 {
1778 {
1779 /* C++0x scoped enumerations don't implicitly convert to integral
1780 type; if we stripped an explicit conversion to a larger type we
1781 need to replace it so common_type will still work. */
1786 }
1788 }
1790 /* This is a helper function of build_binary_op.
1792 For certain operations if both args were extended from the same
1793 smaller type, do the arithmetic in that type and then extend.
1795 BITWISE indicates a bitwise operation.
1796 For them, this optimization is safe only if
1797 both args are zero-extended or both are sign-extended.
1798 Otherwise, we might change the result.
1799 Eg, (short)-1 | (unsigned short)-1 is (int)-1
1800 but calculated in (unsigned short) it would be (unsigned short)-1.
1801 */
1802 tree
1804 {
1808 tree type;
1810 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents
1811 excessive narrowing when we call get_narrower below. For
1812 example, suppose that OP0 is of unsigned int extended
1813 from signed char and that RESULT_TYPE is long long int.
1814 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look
1815 like
1817 (long long int) (unsigned int) signed_char
1819 which get_narrower would narrow down to
1821 (unsigned int) signed char
1823 If we do not cast OP0 first, get_narrower would return
1824 signed_char, which is inconsistent with the case of the
1825 explicit cast. */
1832 /* UNS is 1 if the operation to be done is an unsigned one. */
1835 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
1836 but it *requires* conversion to FINAL_TYPE. */
1847 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
1849 /* For bitwise operations, signedness of nominal type
1850 does not matter. Consider only how operands were extended. */
1854 /* Note that in all three cases below we refrain from optimizing
1855 an unsigned operation on sign-extended args.
1856 That would not be valid. */
1858 /* Both args variable: if both extended in same way
1859 from same width, do it in that width.
1860 Do it unsigned if args were zero-extended. */
1867 return c_common_signed_or_unsigned_type
1874 && (type
1885 && (type
1893 }
1895 /* Warns if the conversion of EXPR to TYPE may alter a value.
1896 This is a helper function for warnings_for_convert_and_check. */
1898 static void
1900 {
1911 /* If any operand is artificial, then this expression was generated
1912 by the compiler and we do not warn. */
1914 {
1918 }
1921 {
1934 /* Conversion from boolean to a signed:1 bit-field (which only
1935 can hold the values 0 and -1) doesn't lose information - but
1936 it does change the value. */
1945 /* Warn for real constant that is not an exact integer converted
1946 to integer type. */
1949 {
1952 }
1953 /* Warn for an integer constant that does not fit into integer type. */
1957 {
1965 else
1967 }
1969 {
1970 /* Warn for an integer constant that does not fit into real type. */
1972 {
1976 }
1977 /* Warn for a real constant that does not fit into a smaller
1978 real type. */
1981 {
1985 }
1986 }
1996 {
1997 /* In case of COND_EXPR, if both operands are constants or
1998 COND_EXPR, then we do not care about the type of COND_EXPR,
1999 only about the conversion of each operand. */
2007 {
2011 }
2012 /* Fall through. */
2013 }
2017 /* Warn for real types converted to integer types. */
2024 {
2025 /* Don't warn about unsigned char y = 0xff, x = (int) y; */
2029 /* Don't warn for short y; short x = ((int)y & 0xff); */
2033 {
2034 /* If both args were extended from a shortest type,
2035 use that type if that is safe. */
2042 {
2048 /* If one of the operands is a non-negative constant
2049 that fits in the target type, then the type of the
2050 other operand does not matter. */
2059 /* If constant is unsigned and fits in the target
2060 type, then the result will also fit. */
2062 && unsigned0
2065 && unsigned1
2068 }
2069 }
2070 /* Warn for integer types converted to smaller integer types. */
2074 /* When they are the same width but different signedness,
2075 then the value may change. */
2078 /* Even when converted to a bigger type, if the type is
2079 unsigned but expr is signed, then negative values
2080 will be changed. */
2085 }
2087 /* Warn for integer types converted to real types if and only if
2088 all the range of values of the integer type cannot be
2089 represented by the real type. */
2092 {
2096 /* Don't warn about char y = 0xff; float x = (int) y; */
2108 }
2110 /* Warn for real types converted to smaller real types. */
2121 }
2122 }
2124 /* Produce warnings after a conversion. RESULT is the result of
2125 converting EXPR to TYPE. This is a helper function for
2126 convert_and_check and cp_convert_and_check. */
2128 void
2130 {
2135 {
2136 /* Do not diagnose overflow in a constant expression merely
2137 because a conversion overflowed. */
2142 {
2143 /* This detects cases like converting -129 or 256 to
2144 unsigned char. */
2148 else
2150 }
2154 /* No warning for converting 0x80000000 to int. */
2162 else
2164 }
2169 else
2171 }
2174 /* Convert EXPR to TYPE, warning about conversion problems with constants.
2175 Invoke this function on every expression that is converted implicitly,
2176 i.e. because of language rules and not because of an explicit cast. */
2178 tree
2180 {
2181 tree result;
2182 tree expr_for_warning;
2184 /* Convert from a value with possible excess precision rather than
2185 via the semantic type, but do not warn about values not fitting
2186 exactly in the semantic type. */
2188 {
2194 }
2195 else
2209 }
2210 \f
2211 /* A node in a list that describes references to variables (EXPR), which are
2212 either read accesses if WRITER is zero, or write accesses, in which case
2213 WRITER is the parent of EXPR. */
2214 struct tlist
2215 {
2218 };
2220 /* Used to implement a cache the results of a call to verify_tree. We only
2221 use this for SAVE_EXPRs. */
2222 struct tlist_cache
2223 {
2227 tree expr;
2228 };
2230 /* Obstack to use when allocating tlist structures, and corresponding
2231 firstobj. */
2235 /* Keep track of the identifiers we've warned about, so we can avoid duplicate
2236 warnings. */
2238 /* SAVE_EXPRs need special treatment. We process them only once and then
2239 cache the results. */
2251 /* Create a new struct tlist and fill in its fields. */
2254 {
2261 }
2263 /* Add duplicates of the nodes found in ADD to the list *TO. If EXCLUDE_WRITER
2264 is nonnull, we ignore any node we find which has a writer equal to it. */
2266 static void
2268 {
2270 {
2277 }
2278 }
2280 /* Merge the nodes of ADD into TO. This merging process is done so that for
2281 each variable that already exists in TO, no new node is added; however if
2282 there is a write access recorded in ADD, and an occurrence on TO is only
2283 a read access, then the occurrence in TO will be modified to record the
2284 write. */
2286 static void
2288 {
2295 {
2302 {
2306 }
2308 {
2312 }
2314 }
2315 }
2317 /* WRITTEN is a variable, WRITER is its parent. Warn if any of the variable
2318 references in list LIST conflict with it, excluding reads if ONLY writers
2319 is nonzero. */
2321 static void
2324 {
2327 /* Avoid duplicate warnings. */
2333 {
2337 {
2342 }
2344 }
2345 }
2347 /* Given a list LIST of references to variables, find whether any of these
2348 can cause conflicts due to missing sequence points. */
2350 static void
2352 {
2356 {
2359 }
2360 }
2362 /* Return nonzero if X is a tree that can be verified by the sequence point
2363 warnings. */
2364 static int
2366 {
2373 /* VOID_TYPE_P (TREE_TYPE (x)) is workaround for cp/tree.c
2374 (lvalue_p) crash on TRY/CATCH. */
2381 /* No point to track non-const calls, they will never satisfy
2382 operand_equal_p. */
2390 }
2392 /* Return nonzero if X and Y appear to be the same candidate (or NULL) */
2393 static bool
2395 {
2397 }
2399 /* Walk the tree X, and record accesses to variables. If X is written by the
2400 parent tree, WRITER is the parent.
2401 We store accesses in one of the two lists: PBEFORE_SP, and PNO_SP. If this
2402 expression or its only operand forces a sequence point, then everything up
2403 to the sequence point is stored in PBEFORE_SP. Everything else gets stored
2404 in PNO_SP.
2405 Once we return, we will have emitted warnings if any subexpression before
2406 such a sequence point could be undefined. On a higher level, however, the
2407 sequence point may not be relevant, and we'll merge the two lists.
2409 Example: (b++, a) + b;
2410 The call that processes the COMPOUND_EXPR will store the increment of B
2411 in PBEFORE_SP, and the use of A in PNO_SP. The higher-level call that
2412 processes the PLUS_EXPR will need to merge the two lists so that
2413 eventually, all accesses end up on the same list (and we'll warn about the
2414 unordered subexpressions b++ and b.
2416 A note on merging. If we modify the former example so that our expression
2417 becomes
2418 (b++, b) + a
2419 care must be taken not simply to add all three expressions into the final
2420 PNO_SP list. The function merge_tlist takes care of that by merging the
2421 before-SP list of the COMPOUND_EXPR into its after-SP list in a special
2422 way, so that no more than one access to B is recorded. */
2424 static void
2426 tree writer)
2427 {
2432 /* X may be NULL if it is the operand of an empty statement expression
2433 ({ }). */
2437 restart:
2445 {
2477 /* Rather than add both tmp_nosp and tmp_list2, we have to merge the
2478 two first, to avoid warning for (a ? b++ : b++). */
2494 /* Expressions inside the LHS are not ordered wrt. the sequence points
2495 in the RHS. Example:
2496 *a = (a++, 2)
2497 Despite the fact that the modification of "a" is in the before_sp
2498 list (tmp_before), it conflicts with the use of "a" in the LHS.
2499 We can handle this by adding the contents of tmp_list3
2500 to those of tmp_before, and redoing the collision warnings for that
2501 list. */
2504 /* Exclude the LHS itself here; we first have to merge it into the
2505 tmp_nosp list. This is done to avoid warning for "a = a"; if we
2506 didn't exclude the LHS, we'd get it twice, once as a read and once
2507 as a write. */
2518 /* We need to warn about conflicts among arguments and conflicts between
2519 args and the function address. Side effects of the function address,
2520 however, are not ordered by the sequence point of the call. */
2521 {
2522 call_expr_arg_iterator iter;
2523 tree arg;
2527 {
2532 }
2537 }
2540 /* Scan all the list, e.g. indices of multi dimensional array. */
2542 {
2548 }
2552 {
2559 {
2571 {
2575 }
2578 }
2582 }
2592 /* For other expressions, simply recurse on their operands.
2593 Manual tail recursion for unary expressions.
2594 Other non-expressions need not be processed. */
2596 {
2600 }
2602 {
2606 {
2611 }
2612 }
2614 }
2615 }
2617 /* Try to warn for undefined behavior in EXPR due to missing sequence
2618 points. */
2620 DEBUG_FUNCTION void
2622 {
2628 {
2631 }
2636 }
2637 \f
2638 /* Validate the expression after `case' and apply default promotions. */
2640 static tree
2642 {
2647 /* Promote char or short to int. */
2650 {
2653 }
2658 }
2659 \f
2660 /* See if the case values LOW and HIGH are in the range of the original
2661 type (i.e. before the default conversion to int) of the switch testing
2662 expression.
2663 TYPE is the promoted type of the testing expression, and ORIG_TYPE is
2664 the type before promoting it. CASE_LOW_P is a pointer to the lower
2665 bound of the case label, and CASE_HIGH_P is the upper bound or NULL
2666 if the case is not a case range.
2667 The caller has to make sure that we are not called with NULL for
2668 CASE_LOW_P (i.e. the default case).
2669 Returns true if the case label is in range of ORIG_TYPE (saturated or
2670 untouched) or false if the label is out of range. */
2672 static bool
2675 {
2680 /* If there was a problem with the original type, do nothing. */
2687 /* Case label is less than minimum for type. */
2690 {
2693 }
2695 /* Case value is greater than maximum for type. */
2698 {
2701 }
2703 /* Saturate lower case label value to minimum. */
2706 {
2710 }
2712 /* Saturate upper case label value to maximum. */
2715 {
2719 }
2727 }
2728 \f
2729 /* Return an integer type with BITS bits of precision,
2730 that is unsigned if UNSIGNEDP is nonzero, otherwise signed. */
2732 tree
2734 {
2773 }
2775 /* Return a fixed-point type that has at least IBIT ibits and FBIT fbits
2776 that is unsigned if UNSIGNEDP is nonzero, otherwise signed;
2777 and saturating if SATP is nonzero, otherwise not saturating. */
2779 tree
2782 {
2786 else
2794 {
2796 "fixed-point types that have too many integral and "
2799 }
2802 }
2804 /* Used for communication between c_common_type_for_mode and
2805 c_register_builtin_type. */
2808 /* Return a data type that has machine mode MODE.
2809 If the mode is an integer,
2810 then UNSIGNEDP selects between signed and unsigned types.
2811 If the mode is a fixed-point mode,
2812 then UNSIGNEDP selects between saturating and nonsaturating types. */
2814 tree
2816 {
2817 tree t;
2854 #if HOST_BITS_PER_WIDE_INT >= 64
2857 #endif
2882 {
2884 tree inner_type;
2900 }
2902 {
2907 }
2917 {
3003 }
3010 }
3012 tree
3014 {
3016 }
3018 /* Return a signed type the same as TYPE in other respects. */
3020 tree
3022 {
3024 }
3026 /* Return a type the same as TYPE except unsigned or
3027 signed according to UNSIGNEDP. */
3029 tree
3031 {
3032 tree type1;
3034 /* This block of code emulates the behavior of the old
3035 c_common_unsigned_type. In particular, it returns
3036 long_unsigned_type_node if passed a long, even when a int would
3037 have the same size. This is necessary for warnings to work
3038 correctly in archs where sizeof(int) == sizeof(long) */
3041 if (type1 == signed_char_type_node || type1 == char_type_node || type1 == unsigned_char_type_node)
3057 #if HOST_BITS_PER_WIDE_INT >= 64
3060 #endif
3070 #define C_COMMON_FIXED_TYPES(NAME) \
3071 if (type1 == short_ ## NAME ## _type_node \
3072 || type1 == unsigned_short_ ## NAME ## _type_node) \
3073 return unsignedp ? unsigned_short_ ## NAME ## _type_node \
3074 : short_ ## NAME ## _type_node; \
3075 if (type1 == NAME ## _type_node \
3076 || type1 == unsigned_ ## NAME ## _type_node) \
3077 return unsignedp ? unsigned_ ## NAME ## _type_node \
3078 : NAME ## _type_node; \
3079 if (type1 == long_ ## NAME ## _type_node \
3080 || type1 == unsigned_long_ ## NAME ## _type_node) \
3081 return unsignedp ? unsigned_long_ ## NAME ## _type_node \
3082 : long_ ## NAME ## _type_node; \
3083 if (type1 == long_long_ ## NAME ## _type_node \
3084 || type1 == unsigned_long_long_ ## NAME ## _type_node) \
3085 return unsignedp ? unsigned_long_long_ ## NAME ## _type_node \
3086 : long_long_ ## NAME ## _type_node;
3088 #define C_COMMON_FIXED_MODE_TYPES(NAME) \
3089 if (type1 == NAME ## _type_node \
3090 || type1 == u ## NAME ## _type_node) \
3091 return unsignedp ? u ## NAME ## _type_node \
3092 : NAME ## _type_node;
3094 #define C_COMMON_FIXED_TYPES_SAT(NAME) \
3095 if (type1 == sat_ ## short_ ## NAME ## _type_node \
3096 || type1 == sat_ ## unsigned_short_ ## NAME ## _type_node) \
3097 return unsignedp ? sat_ ## unsigned_short_ ## NAME ## _type_node \
3098 : sat_ ## short_ ## NAME ## _type_node; \
3099 if (type1 == sat_ ## NAME ## _type_node \
3100 || type1 == sat_ ## unsigned_ ## NAME ## _type_node) \
3101 return unsignedp ? sat_ ## unsigned_ ## NAME ## _type_node \
3102 : sat_ ## NAME ## _type_node; \
3103 if (type1 == sat_ ## long_ ## NAME ## _type_node \
3104 || type1 == sat_ ## unsigned_long_ ## NAME ## _type_node) \
3105 return unsignedp ? sat_ ## unsigned_long_ ## NAME ## _type_node \
3106 : sat_ ## long_ ## NAME ## _type_node; \
3107 if (type1 == sat_ ## long_long_ ## NAME ## _type_node \
3108 || type1 == sat_ ## unsigned_long_long_ ## NAME ## _type_node) \
3109 return unsignedp ? sat_ ## unsigned_long_long_ ## NAME ## _type_node \
3110 : sat_ ## long_long_ ## NAME ## _type_node;
3112 #define C_COMMON_FIXED_MODE_TYPES_SAT(NAME) \
3113 if (type1 == sat_ ## NAME ## _type_node \
3114 || type1 == sat_ ## u ## NAME ## _type_node) \
3115 return unsignedp ? sat_ ## u ## NAME ## _type_node \
3116 : sat_ ## NAME ## _type_node;
3142 /* For ENUMERAL_TYPEs in C++, must check the mode of the types, not
3143 the precision; they have precision set to match their range, but
3144 may use a wider mode to match an ABI. If we change modes, we may
3145 wind up with bad conversions. For INTEGER_TYPEs in C, must check
3146 the precision as well, so as to yield correct results for
3147 bit-field types. C++ does not have these separate bit-field
3148 types, and producing a signed or unsigned variant of an
3149 ENUMERAL_TYPE may cause other problems as well. */
3155 #define TYPE_OK(node) \
3156 (TYPE_MODE (type) == TYPE_MODE (node) \
3157 && TYPE_PRECISION (type) == TYPE_PRECISION (node))
3176 #if HOST_BITS_PER_WIDE_INT >= 64
3179 #endif
3188 #undef TYPE_OK
3191 }
3193 /* Build a bit-field integer type for the given WIDTH and UNSIGNEDP. */
3195 tree
3197 {
3198 /* Extended integer types of the same width as a standard type have
3199 lesser rank, so those of the same width as int promote to int or
3200 unsigned int and are valid for printf formats expecting int or
3201 unsigned int. To avoid such special cases, avoid creating
3202 extended integer types for bit-fields if a standard integer type
3203 is available. */
3220 }
3222 /* The C version of the register_builtin_type langhook. */
3224 void
3226 {
3227 tree decl;
3237 }
3238 \f
3239 /* Print an error message for invalid operands to arith operation
3240 CODE with TYPE0 for operand 0, and TYPE1 for operand 1.
3241 LOCATION is the location of the message. */
3243 void
3246 {
3250 {
3295 }
3299 }
3300 \f
3301 /* Subroutine of build_binary_op, used for comparison operations.
3302 See if the operands have both been converted from subword integer types
3303 and, if so, perhaps change them both back to their original type.
3304 This function is also responsible for converting the two operands
3305 to the proper common type for comparison.
3307 The arguments of this function are all pointers to local variables
3308 of build_binary_op: OP0_PTR is &OP0, OP1_PTR is &OP1,
3309 RESTYPE_PTR is &RESULT_TYPE and RESCODE_PTR is &RESULTCODE.
3311 If this function returns nonzero, it means that the comparison has
3312 a constant value. What this function returns is an expression for
3313 that value. */
3315 tree
3318 {
3319 tree type;
3327 /* Throw away any conversions to wider types
3328 already present in the operands. */
3333 /* If primopN is first sign-extended from primopN's precision to opN's
3334 precision, then zero-extended from opN's precision to
3335 *restype_ptr precision, shortenings might be invalid. */
3338 && !unsignedp0
3343 && !unsignedp1
3347 /* Handle the case that OP0 does not *contain* a conversion
3348 but it *requires* conversion to FINAL_TYPE. */
3355 /* If one of the operands must be floated, we cannot optimize. */
3359 /* If first arg is constant, swap the args (changing operation
3360 so value is preserved), for canonicalization. Don't do this if
3361 the second arg is 0. */
3366 {
3383 {
3398 }
3400 }
3402 /* If comparing an integer against a constant more bits wide,
3403 maybe we can deduce a value of 1 or 0 independent of the data.
3404 Or else truncate the constant now
3405 rather than extend the variable at run time.
3407 This is only interesting if the constant is the wider arg.
3408 Also, it is not safe if the constant is unsigned and the
3409 variable arg is signed, since in this case the variable
3410 would be sign-extended and then regarded as unsigned.
3411 Our technique fails in this case because the lowest/highest
3412 possible unsigned results don't follow naturally from the
3413 lowest/highest possible values of the variable operand.
3414 For just EQ_EXPR and NE_EXPR there is another technique that
3415 could be used: see if the constant can be faithfully represented
3416 in the other operand's type, by truncating it and reextending it
3417 and see if that preserves the constant's value. */
3423 {
3426 /* 1 if comparison is nominally unsigned. */
3428 tree val;
3440 {
3441 /* Convert primop1 to target type, but do not introduce
3442 additional overflow. We know primop1 is an int_cst. */
3446 }
3448 {
3451 }
3454 {
3459 }
3460 else
3461 {
3466 }
3469 /* This used to be a switch, but Genix compiler can't handle that. */
3471 {
3474 }
3476 {
3479 }
3481 {
3486 }
3488 {
3493 }
3495 {
3500 }
3502 {
3507 }
3509 /* If primop0 was sign-extended and unsigned comparison specd,
3510 we did a signed comparison above using the signed type bounds.
3511 But the comparison we output must be unsigned.
3513 Also, for inequalities, VAL is no good; but if the signed
3514 comparison had *any* fixed result, it follows that the
3515 unsigned comparison just tests the sign in reverse
3516 (positive values are LE, negative ones GE).
3517 So we can generate an unsigned comparison
3518 against an extreme value of the signed type. */
3521 {
3524 {
3539 }
3541 }
3544 {
3549 }
3552 {
3553 /* Don't forget to evaluate PRIMOP0 if it has side effects. */
3557 }
3559 /* Value is not predetermined, but do the comparison
3560 in the type of the operand that is not constant.
3561 TYPE is already properly set. */
3562 }
3564 /* If either arg is decimal float and the other is float, find the
3565 proper common type to use for comparison. */
3576 /* If args' natural types are both narrower than nominal type
3577 and both extend in the same manner, compare them
3578 in the type of the wider arg.
3579 Otherwise must actually extend both to the nominal
3580 common type lest different ways of extending
3581 alter the result.
3582 (eg, (short)-1 == (unsigned short)-1 should be 0.) */
3587 {
3591 type);
3592 /* Make sure shorter operand is extended the right way
3593 to match the longer operand. */
3594 primop0
3597 primop0);
3598 primop1
3601 primop1);
3602 }
3603 else
3604 {
3605 /* Here we must do the comparison on the nominal type
3606 using the args exactly as we received them. */
3613 {
3616 {
3618 /* All unsigned values are >= 0, so we warn. However,
3619 if OP0 is a constant that is >= 0, the signedness of
3620 the comparison isn't an issue, so suppress the
3621 warning. */
3625 primop0))))
3635 primop0))))
3643 }
3646 {
3647 /* Don't forget to evaluate PRIMOP0 if it has side effects. */
3652 }
3653 }
3654 }
3662 }
3663 \f
3664 /* Return a tree for the sum or difference (RESULTCODE says which)
3665 of pointer PTROP and integer INTOP. */
3667 tree
3670 {
3673 /* The result is a pointer of the same type that is being added. */
3677 {
3681 }
3683 {
3687 }
3689 {
3693 }
3694 else
3697 /* We are manipulating pointer values, so we don't need to warn
3698 about relying on undefined signed overflow. We disable the
3699 warning here because we use integer types so fold won't know that
3700 they are really pointers. */
3703 /* If what we are about to multiply by the size of the elements
3704 contains a constant term, apply distributive law
3705 and multiply that constant term separately.
3706 This helps produce common subexpressions. */
3711 /* If the constant comes from pointer subtraction,
3712 skip this optimization--it would cause an error. */
3714 /* If the constant is unsigned, and smaller than the pointer size,
3715 then we must skip this optimization. This is because it could cause
3716 an overflow error if the constant is negative but INTOP is not. */
3720 {
3725 /* Convert both subexpression types to the type of intop,
3726 because weird cases involving pointer arithmetic
3727 can result in a sum or difference with different type args. */
3732 }
3734 /* Convert the integer argument to a type the same size as sizetype
3735 so the multiply won't overflow spuriously. */
3741 /* Replace the integer argument with a suitable product by the object size.
3742 Do this multiplication as signed, then convert to the appropriate type
3743 for the pointer operation and disregard an overflow that occured only
3744 because of the sign-extension change in the latter conversion. */
3745 {
3753 }
3755 /* Create the sum or difference. */
3764 }
3765 \f
3766 /* Wrap a C_MAYBE_CONST_EXPR around an expression that is fully folded
3767 and if NON_CONST is known not to be permitted in an evaluated part
3768 of a constant expression. */
3770 tree
3772 {
3776 /* This should never be called for C++. */
3780 /* The result of folding may have a NOP_EXPR to set TREE_NO_WARNING. */
3789 }
3791 /* Wrap a SAVE_EXPR around EXPR, if appropriate. Like save_expr, but
3792 for C folds the inside expression and wraps a C_MAYBE_CONST_EXPR
3793 around the SAVE_EXPR if needed so that c_fully_fold does not need
3794 to look inside SAVE_EXPRs. */
3796 tree
3798 {
3807 }
3809 /* Return whether EXPR is a declaration whose address can never be
3810 NULL. */
3812 bool
3814 {
3819 }
3821 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
3822 or for an `if' or `while' statement or ?..: exp. It should already
3823 have been validated to be of suitable type; otherwise, a bad
3824 diagnostic may result.
3826 The EXPR is located at LOCATION.
3828 This preparation consists of taking the ordinary
3829 representation of an expression expr and producing a valid tree
3830 boolean expression describing whether expr is nonzero. We could
3831 simply always do build_binary_op (NE_EXPR, expr, truthvalue_false_node, 1),
3832 but we optimize comparisons, &&, ||, and !.
3834 The resulting type should always be `truthvalue_type_node'. */
3836 tree
3838 {
3840 {
3882 ? truthvalue_true_node
3888 ? truthvalue_true_node
3893 /* Fall through. */
3896 {
3899 {
3900 /* Common Ada/Pascal programmer's mistake. */
3902 OPT_Waddress,
3904 inner);
3906 }
3908 }
3925 /* These don't change whether an object is nonzero or zero. */
3930 /* These don't change whether an object is zero or nonzero, but
3931 we can't ignore them if their second arg has side-effects. */
3933 {
3936 c_common_truthvalue_conversion
3939 }
3940 else
3945 /* Distribute the conversion into the arms of a COND_EXPR. */
3947 {
3950 /* In C++ one of the arms might have void type if it is throw. */
3958 }
3959 else
3960 {
3961 /* Folding will happen later for C. */
3969 }
3971 CASE_CONVERT:
3972 {
3976 /* Don't cancel the effect of a CONVERT_EXPR from a REFERENCE_TYPE,
3977 since that affects how `default_conversion' will behave. */
3981 /* Don't strip a conversion from C++0x scoped enum, since they
3982 don't implicitly convert to other types. */
3986 /* If this isn't narrowing the argument, we can ignore it. */
3990 }
3996 {
4000 }
4005 }
4008 {
4010 expr = (build_binary_op
4014 c_common_truthvalue_conversion
4017 c_common_truthvalue_conversion
4022 }
4025 {
4030 }
4031 else
4034 ret:
4037 }
4038 \f
4047 /* Apply the TYPE_QUALS to the new DECL. */
4049 void
4051 {
4059 /* An object declared 'const' is only readonly after it is
4060 initialized. We don't have any way of expressing this currently,
4061 so we need to be conservative and unset TREE_READONLY for types
4062 with constructors. Otherwise aliasing code will ignore stores in
4063 an inline constructor. */
4067 {
4070 }
4072 {
4074 /* Allow 'restrict' on arrays of pointers.
4075 FIXME currently we just ignore it. */
4081 }
4082 }
4084 /* Hash function for the problem of multiple type definitions in
4085 different files. This must hash all types that will compare
4086 equal via comptypes to the same value. In practice it hashes
4087 on some of the simple stuff and leaves the details to comptypes. */
4089 static hashval_t
4091 {
4095 tree t2;
4097 {
4098 /* For pointers, hash on pointee type plus some swizzling. */
4101 /* Hash on number of elements and total size. */
4120 }
4121 /* FIXME: We want to use a DECL_CHAIN iteration method here, but
4122 TYPE_VALUES of ENUMERAL_TYPEs is stored as a TREE_LIST. */
4124 /* We might have a VLA here. */
4127 else
4130 }
4134 /* Return the typed-based alias set for T, which may be an expression
4135 or a type. Return -1 if we don't do anything special. */
4137 alias_set_type
4139 {
4140 tree u;
4143 /* For VLAs, use the alias set of the element type rather than the
4144 default of alias set 0 for types compared structurally. */
4146 {
4150 }
4152 /* Permit type-punning when accessing a union, provided the access
4153 is directly through the union. For example, this code does not
4154 permit taking the address of a union member and then storing
4155 through it. Even the type-punning allowed here is a GCC
4156 extension, albeit a common and useful one; the C standard says
4157 that such accesses have implementation-defined behavior. */
4165 /* That's all the expressions we handle specially. */
4169 /* The C standard guarantees that any object may be accessed via an
4170 lvalue that has character type. */
4176 /* The C standard specifically allows aliasing between signed and
4177 unsigned variants of the same type. We treat the signed
4178 variant as canonical. */
4180 {
4183 /* t1 == t can happen for boolean nodes which are always unsigned. */
4186 }
4188 /* Handle the case of multiple type nodes referring to "the same" type,
4189 which occurs with IMA. These share an alias set. FIXME: Currently only
4190 C90 is handled. (In C99 type compatibility is not transitive, which
4191 complicates things mightily. The alias set splay trees can theoretically
4192 represent this, but insertion is tricky when you consider all the
4193 different orders things might arrive in.) */
4198 /* Save time if there's only one input file. */
4202 /* Pointers need special handling if they point to any type that
4203 needs special handling (below). */
4205 {
4206 tree t2;
4207 /* Find bottom type under any nested POINTERs. */
4211 ;
4219 }
4220 /* These are the only cases that need special handling. */
4227 /* Undefined? */
4231 /* Look up t in hash table. Only one of the compatible types within each
4232 alias set is recorded in the table. */
4236 NULL);
4239 {
4242 }
4243 else
4244 /* Our caller will assign and record (in t) a new alias set; all we need
4245 to do is remember t in the hash table. */
4249 }
4250 \f
4251 /* Compute the value of 'sizeof (TYPE)' or '__alignof__ (TYPE)', where
4252 the second parameter indicates which OPERATOR is being applied.
4253 The COMPLAIN flag controls whether we should diagnose possibly
4254 ill-formed constructs or not. LOC is the location of the SIZEOF or
4255 TYPEOF operator. */
4257 tree
4260 {
4268 {
4270 {
4277 }
4278 else
4280 }
4282 {
4290 }
4292 {
4297 }
4298 else
4299 {
4301 /* Convert in case a char is more than one unit. */
4305 else
4307 }
4309 /* VALUE will have an integer type with TYPE_IS_SIZETYPE set.
4310 TYPE_IS_SIZETYPE means that certain things (like overflow) will
4311 never happen. However, this node should really have type
4312 `size_t', which is just a typedef for an ordinary integer type. */
4317 }
4319 /* Implement the __alignof keyword: Return the minimum required
4320 alignment of EXPR, measured in bytes. For VAR_DECLs,
4321 FUNCTION_DECLs and FIELD_DECLs return DECL_ALIGN (which can be set
4322 from an "aligned" __attribute__ specification). LOC is the
4323 location of the ALIGNOF operator. */
4325 tree
4327 {
4328 tree t;
4335 {
4338 }
4344 {
4351 {
4358 }
4360 }
4361 else
4365 }
4366 \f
4367 /* Handle C and C++ default attributes. */
4369 enum built_in_attribute
4370 {
4371 #define DEF_ATTR_NULL_TREE(ENUM) ENUM,
4372 #define DEF_ATTR_INT(ENUM, VALUE) ENUM,
4373 #define DEF_ATTR_IDENT(ENUM, STRING) ENUM,
4374 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) ENUM,
4376 #undef DEF_ATTR_NULL_TREE
4377 #undef DEF_ATTR_INT
4378 #undef DEF_ATTR_IDENT
4379 #undef DEF_ATTR_TREE_LIST
4380 ATTR_LAST
4381 };
4387 enum c_builtin_type
4388 {
4389 #define DEF_PRIMITIVE_TYPE(NAME, VALUE) NAME,
4390 #define DEF_FUNCTION_TYPE_0(NAME, RETURN) NAME,
4391 #define DEF_FUNCTION_TYPE_1(NAME, RETURN, ARG1) NAME,
4392 #define DEF_FUNCTION_TYPE_2(NAME, RETURN, ARG1, ARG2) NAME,
4393 #define DEF_FUNCTION_TYPE_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
4394 #define DEF_FUNCTION_TYPE_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
4395 #define DEF_FUNCTION_TYPE_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) NAME,
4396 #define DEF_FUNCTION_TYPE_6(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6) NAME,
4397 #define DEF_FUNCTION_TYPE_7(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7) NAME,
4398 #define DEF_FUNCTION_TYPE_VAR_0(NAME, RETURN) NAME,
4399 #define DEF_FUNCTION_TYPE_VAR_1(NAME, RETURN, ARG1) NAME,
4400 #define DEF_FUNCTION_TYPE_VAR_2(NAME, RETURN, ARG1, ARG2) NAME,
4401 #define DEF_FUNCTION_TYPE_VAR_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
4402 #define DEF_FUNCTION_TYPE_VAR_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
4403 #define DEF_FUNCTION_TYPE_VAR_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG6) \
4404 NAME,
4405 #define DEF_POINTER_TYPE(NAME, TYPE) NAME,
4407 #undef DEF_PRIMITIVE_TYPE
4408 #undef DEF_FUNCTION_TYPE_0
4409 #undef DEF_FUNCTION_TYPE_1
4410 #undef DEF_FUNCTION_TYPE_2
4411 #undef DEF_FUNCTION_TYPE_3
4412 #undef DEF_FUNCTION_TYPE_4
4413 #undef DEF_FUNCTION_TYPE_5
4414 #undef DEF_FUNCTION_TYPE_6
4415 #undef DEF_FUNCTION_TYPE_7
4416 #undef DEF_FUNCTION_TYPE_VAR_0
4417 #undef DEF_FUNCTION_TYPE_VAR_1
4418 #undef DEF_FUNCTION_TYPE_VAR_2
4419 #undef DEF_FUNCTION_TYPE_VAR_3
4420 #undef DEF_FUNCTION_TYPE_VAR_4
4421 #undef DEF_FUNCTION_TYPE_VAR_5
4422 #undef DEF_POINTER_TYPE
4423 BT_LAST
4424 };
4428 /* A temporary array for c_common_nodes_and_builtins. Used in
4429 communication with def_fn_type. */
4432 /* A helper function for c_common_nodes_and_builtins. Build function type
4433 for DEF with return type RET and N arguments. If VAR is true, then the
4434 function should be variadic after those N arguments.
4436 Takes special care not to ICE if any of the types involved are
4437 error_mark_node, which indicates that said type is not in fact available
4438 (see builtin_type_for_size). In which case the function type as a whole
4439 should be error_mark_node. */
4441 static void
4443 {
4444 tree t;
4451 {
4457 }
4464 else
4467 egress:
4470 }
4472 /* Build builtin functions common to both C and C++ language
4473 frontends. */
4475 static void
4477 {
4478 #define DEF_PRIMITIVE_TYPE(ENUM, VALUE) \
4479 builtin_types[ENUM] = VALUE;
4480 #define DEF_FUNCTION_TYPE_0(ENUM, RETURN) \
4481 def_fn_type (ENUM, RETURN, 0, 0);
4482 #define DEF_FUNCTION_TYPE_1(ENUM, RETURN, ARG1) \
4483 def_fn_type (ENUM, RETURN, 0, 1, ARG1);
4484 #define DEF_FUNCTION_TYPE_2(ENUM, RETURN, ARG1, ARG2) \
4485 def_fn_type (ENUM, RETURN, 0, 2, ARG1, ARG2);
4486 #define DEF_FUNCTION_TYPE_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
4487 def_fn_type (ENUM, RETURN, 0, 3, ARG1, ARG2, ARG3);
4488 #define DEF_FUNCTION_TYPE_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
4489 def_fn_type (ENUM, RETURN, 0, 4, ARG1, ARG2, ARG3, ARG4);
4490 #define DEF_FUNCTION_TYPE_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
4491 def_fn_type (ENUM, RETURN, 0, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
4492 #define DEF_FUNCTION_TYPE_6(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
4493 ARG6) \
4494 def_fn_type (ENUM, RETURN, 0, 6, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6);
4495 #define DEF_FUNCTION_TYPE_7(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
4496 ARG6, ARG7) \
4497 def_fn_type (ENUM, RETURN, 0, 7, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7);
4498 #define DEF_FUNCTION_TYPE_VAR_0(ENUM, RETURN) \
4499 def_fn_type (ENUM, RETURN, 1, 0);
4500 #define DEF_FUNCTION_TYPE_VAR_1(ENUM, RETURN, ARG1) \
4501 def_fn_type (ENUM, RETURN, 1, 1, ARG1);
4502 #define DEF_FUNCTION_TYPE_VAR_2(ENUM, RETURN, ARG1, ARG2) \
4503 def_fn_type (ENUM, RETURN, 1, 2, ARG1, ARG2);
4504 #define DEF_FUNCTION_TYPE_VAR_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
4505 def_fn_type (ENUM, RETURN, 1, 3, ARG1, ARG2, ARG3);
4506 #define DEF_FUNCTION_TYPE_VAR_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
4507 def_fn_type (ENUM, RETURN, 1, 4, ARG1, ARG2, ARG3, ARG4);
4508 #define DEF_FUNCTION_TYPE_VAR_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
4509 def_fn_type (ENUM, RETURN, 1, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
4510 #define DEF_POINTER_TYPE(ENUM, TYPE) \
4511 builtin_types[(int) ENUM] = build_pointer_type (builtin_types[(int) TYPE]);
4515 #undef DEF_PRIMITIVE_TYPE
4516 #undef DEF_FUNCTION_TYPE_1
4517 #undef DEF_FUNCTION_TYPE_2
4518 #undef DEF_FUNCTION_TYPE_3
4519 #undef DEF_FUNCTION_TYPE_4
4520 #undef DEF_FUNCTION_TYPE_5
4521 #undef DEF_FUNCTION_TYPE_6
4522 #undef DEF_FUNCTION_TYPE_VAR_0
4523 #undef DEF_FUNCTION_TYPE_VAR_1
4524 #undef DEF_FUNCTION_TYPE_VAR_2
4525 #undef DEF_FUNCTION_TYPE_VAR_3
4526 #undef DEF_FUNCTION_TYPE_VAR_4
4527 #undef DEF_FUNCTION_TYPE_VAR_5
4528 #undef DEF_POINTER_TYPE
4533 #define DEF_BUILTIN(ENUM, NAME, CLASS, TYPE, LIBTYPE, BOTH_P, FALLBACK_P, \
4534 NONANSI_P, ATTRS, IMPLICIT, COND) \
4535 if (NAME && COND) \
4536 def_builtin_1 (ENUM, NAME, CLASS, \
4537 builtin_types[(int) TYPE], \
4538 builtin_types[(int) LIBTYPE], \
4539 BOTH_P, FALLBACK_P, NONANSI_P, \
4540 built_in_attributes[(int) ATTRS], IMPLICIT);
4542 #undef DEF_BUILTIN
4550 }
4552 /* Like get_identifier, but avoid warnings about null arguments when
4553 the argument may be NULL for targets where GCC lacks stdint.h type
4554 information. */
4558 {
4560 }
4562 /* Build tree nodes and builtin functions common to both C and C++ language
4563 frontends. */
4565 void
4567 {
4571 tree array_domain_type;
4572 tree va_list_ref_type_node;
4573 tree va_list_arg_type_node;
4575 /* Define `int' and `char' first so that dbx will output them first. */
4579 /* `signed' is the same as `int'. FIXME: the declarations of "signed",
4580 "unsigned long", "long long unsigned" and "unsigned short" were in C++
4581 but not C. Are the conditionals here needed? */
4587 long_unsigned_type_node);
4589 {
4591 int128_integer_type_node);
4593 int128_unsigned_type_node);
4594 }
4598 long_long_integer_type_node);
4600 long_long_unsigned_type_node);
4603 long_long_unsigned_type_node);
4606 short_unsigned_type_node);
4609 short_unsigned_type_node);
4611 /* Define both `signed char' and `unsigned char'. */
4615 /* These are types that c_common_type_for_size and
4616 c_common_type_for_mode use. */
4619 intQI_type_node));
4622 intHI_type_node));
4625 intSI_type_node));
4628 intDI_type_node));
4629 #if HOST_BITS_PER_WIDE_INT >= 64
4632 TYPE_DECL,
4634 intTI_type_node));
4635 #endif
4638 unsigned_intQI_type_node));
4641 unsigned_intHI_type_node));
4644 unsigned_intSI_type_node));
4647 unsigned_intDI_type_node));
4648 #if HOST_BITS_PER_WIDE_INT >= 64
4651 TYPE_DECL,
4653 unsigned_intTI_type_node));
4654 #endif
4656 /* Create the widest literal types. */
4657 widest_integer_literal_type_node
4661 widest_integer_literal_type_node));
4663 widest_unsigned_literal_type_node
4667 widest_unsigned_literal_type_node));
4669 /* `unsigned long' is the standard type for sizeof.
4670 Note that stddef.h uses `unsigned long',
4671 and this must agree, even if long and int are the same size. */
4672 size_type_node =
4677 pid_type_node =
4686 /* Only supported decimal floating point extension if the target
4687 actually supports underlying modes. */
4691 {
4695 }
4698 {
4703 long_long_fract_type_node);
4705 unsigned_short_fract_type_node);
4707 unsigned_fract_type_node);
4709 unsigned_long_fract_type_node);
4711 unsigned_long_long_fract_type_node);
4713 sat_short_fract_type_node);
4716 sat_long_fract_type_node);
4718 sat_long_long_fract_type_node);
4720 sat_unsigned_short_fract_type_node);
4722 sat_unsigned_fract_type_node);
4724 sat_unsigned_long_fract_type_node);
4726 sat_unsigned_long_long_fract_type_node);
4731 long_long_accum_type_node);
4733 unsigned_short_accum_type_node);
4735 unsigned_accum_type_node);
4737 unsigned_long_accum_type_node);
4739 unsigned_long_long_accum_type_node);
4741 sat_short_accum_type_node);
4744 sat_long_accum_type_node);
4746 sat_long_long_accum_type_node);
4748 sat_unsigned_short_accum_type_node);
4750 sat_unsigned_accum_type_node);
4752 sat_unsigned_long_accum_type_node);
4754 sat_unsigned_long_long_accum_type_node);
4756 }
4759 TYPE_DECL,
4761 complex_integer_type_node));
4763 TYPE_DECL,
4765 complex_float_type_node));
4767 TYPE_DECL,
4769 complex_double_type_node));
4773 complex_long_double_type_node));
4776 /* For C++, make fileptr_type_node a distinct void * type until
4777 FILE type is defined. */
4782 /* Set the TYPE_NAME for any variants that were built before
4783 record_builtin_type gave names to the built-in types. */
4784 {
4790 }
4792 /* This node must not be shared. */
4798 /* Make a type to be the domain of a few array types
4799 whose domains don't really matter.
4800 200 is small enough that it always fits in size_t
4801 and large enough that it can hold most function names for the
4802 initializations of __FUNCTION__ and __PRETTY_FUNCTION__. */
4805 /* Make a type for arrays of characters.
4806 With luck nothing will ever really depend on the length of this
4807 array type. */
4808 char_array_type_node
4811 /* Likewise for arrays of ints. */
4812 int_array_type_node
4816 const_string_type_node
4820 /* This is special for C++ so functions can be overloaded. */
4826 {
4829 else
4832 }
4834 /* This is for wide string constants. */
4835 wchar_array_type_node
4838 /* Define 'char16_t'. */
4843 {
4848 }
4850 /* This is for UTF-16 string constants. */
4851 char16_array_type_node
4854 /* Define 'char32_t'. */
4859 {
4864 }
4866 /* This is for UTF-32 string constants. */
4867 char32_array_type_node
4870 wint_type_node =
4873 intmax_type_node =
4875 uintmax_type_node =
4879 sig_atomic_type_node =
4882 int8_type_node =
4885 int16_type_node =
4888 int32_type_node =
4891 int64_type_node =
4894 uint8_type_node =
4897 uint16_type_node =
4900 c_uint32_type_node =
4903 c_uint64_type_node =
4906 int_least8_type_node =
4909 int_least16_type_node =
4912 int_least32_type_node =
4915 int_least64_type_node =
4918 uint_least8_type_node =
4921 uint_least16_type_node =
4924 uint_least32_type_node =
4927 uint_least64_type_node =
4930 int_fast8_type_node =
4933 int_fast16_type_node =
4936 int_fast32_type_node =
4939 int_fast64_type_node =
4942 uint_fast8_type_node =
4945 uint_fast16_type_node =
4948 uint_fast32_type_node =
4951 uint_fast64_type_node =
4954 intptr_type_node =
4957 uintptr_type_node =
4960 default_function_type
4962 ptrdiff_type_node
4969 va_list_type_node));
4971 {
4974 tree ptype;
4977 {
4981 ptype));
4983 }
4984 }
4987 {
4990 }
4991 else
4992 {
4995 }
5002 /* Create the built-in __null node. It is important that this is
5003 not shared. */
5007 /* Since builtin_types isn't gc'ed, don't export these nodes. */
5009 }
5011 /* The number of named compound-literals generated thus far. */
5014 /* Set DECL_NAME for DECL, a VAR_DECL for a compound-literal. */
5016 void
5018 {
5021 compound_literal_number);
5022 compound_literal_number++;
5024 }
5026 tree
5028 {
5032 }
5035 /* Linked list of disabled built-in functions. */
5038 {
5046 /* Disable a built-in function specified by -fno-builtin-NAME. If NAME
5047 begins with "__builtin_", give an error. */
5049 void
5051 {
5054 else
5055 {
5060 }
5061 }
5064 /* Return true if the built-in function NAME has been disabled, false
5065 otherwise. */
5067 static bool
5069 {
5072 {
5075 }
5077 }
5080 /* Worker for DEF_BUILTIN.
5081 Possibly define a builtin function with one or two names.
5082 Does not declare a non-__builtin_ function if flag_no_builtin, or if
5083 nonansi_p and flag_no_nonansi_builtin. */
5085 static void
5092 {
5093 tree decl;
5106 fnattrs);
5116 }
5117 \f
5118 /* Nonzero if the type T promotes to int. This is (nearly) the
5119 integral promotions defined in ISO C99 6.3.1.1/2. */
5121 bool
5123 {
5125 {
5135 /* ??? Technically all enumerations not larger than an int
5136 promote to an int. But this is used along code paths
5137 that only want to notice a size change. */
5145 }
5146 }
5148 /* Return 1 if PARMS specifies a fixed number of parameters
5149 and none of their types is affected by default promotions. */
5151 int
5153 {
5154 const_tree t;
5156 {
5173 }
5175 }
5177 /* Recursively remove any '*' or '&' operator from TYPE. */
5178 tree
5180 {
5184 }
5186 /* Recursively remove pointer or array type from TYPE. */
5187 tree
5189 {
5193 }
5195 /* Used to compare case labels. K1 and K2 are actually tree nodes
5196 representing case labels, or NULL_TREE for a `default' label.
5197 Returns -1 if K1 is ordered before K2, -1 if K1 is ordered after
5198 K2, and 0 if K1 and K2 are equal. */
5200 int
5202 {
5203 /* Consider a NULL key (such as arises with a `default' label) to be
5204 smaller than anything else. */
5211 }
5213 /* Process a case label, located at LOC, for the range LOW_VALUE
5214 ... HIGH_VALUE. If LOW_VALUE and HIGH_VALUE are both NULL_TREE
5215 then this case label is actually a `default' label. If only
5216 HIGH_VALUE is NULL_TREE, then case label was declared using the
5217 usual C/C++ syntax, rather than the GNU case range extension.
5218 CASES is a tree containing all the case ranges processed so far;
5219 COND is the condition for the switch-statement itself. Returns the
5220 CASE_LABEL_EXPR created, or ERROR_MARK_NODE if no CASE_LABEL_EXPR
5221 is created. */
5223 tree
5226 {
5227 tree type;
5228 tree label;
5229 tree case_label;
5230 splay_tree_node node;
5232 /* Create the LABEL_DECL itself. */
5235 /* If there was an error processing the switch condition, bail now
5236 before we get more confused. */
5244 {
5247 }
5249 /* Case ranges are a GNU extension. */
5256 {
5261 }
5263 {
5268 }
5271 {
5272 /* If the LOW_VALUE and HIGH_VALUE are the same, then this isn't
5273 really a case range, even though it was written that way.
5274 Remove the HIGH_VALUE to simplify later processing. */
5279 }
5281 /* See if the case is in range of the type of the original testing
5282 expression. If both low_value and high_value are out of range,
5283 don't insert the case label and return NULL_TREE. */
5289 /* Look up the LOW_VALUE in the table of case labels we already
5290 have. */
5292 /* If there was not an exact match, check for overlapping ranges.
5293 There's no need to do this if there's no LOW_VALUE or HIGH_VALUE;
5294 that's a `default' label and the only overlap is an exact match. */
5296 {
5297 splay_tree_node low_bound;
5298 splay_tree_node high_bound;
5300 /* Even though there wasn't an exact match, there might be an
5301 overlap between this case range and another case range.
5302 Since we've (inductively) not allowed any overlapping case
5303 ranges, we simply need to find the greatest low case label
5304 that is smaller that LOW_VALUE, and the smallest low case
5305 label that is greater than LOW_VALUE. If there is an overlap
5306 it will occur in one of these two ranges. */
5312 /* Check to see if the LOW_BOUND overlaps. It is smaller than
5313 the LOW_VALUE, so there is no need to check unless the
5314 LOW_BOUND is in fact itself a case range. */
5320 /* Check to see if the HIGH_BOUND overlaps. The low end of that
5321 range is bigger than the low end of the current range, so we
5322 are only interested if the current range is a real range, and
5323 not an ordinary case label. */
5325 && high_value
5327 high_value)
5330 }
5331 /* If there was an overlap, issue an error. */
5333 {
5337 {
5341 }
5343 {
5346 }
5347 else
5348 {
5352 }
5354 }
5356 /* Add a CASE_LABEL to the statement-tree. */
5358 /* Register this case label in the splay tree. */
5365 error_out:
5366 /* Add a label so that the back-end doesn't think that the beginning of
5367 the switch is unreachable. Note that we do not add a case label, as
5368 that just leads to duplicates and thence to failure later on. */
5370 {
5373 }
5375 }
5377 /* Subroutines of c_do_switch_warnings, called via splay_tree_foreach.
5378 Used to verify that case values match up with enumerator values. */
5380 static void
5382 {
5385 /* ??? Not working too hard to print the double-word value.
5386 Should perhaps be done with %lwd in the diagnostic routines? */
5395 else
5404 buf);
5405 else
5410 }
5412 /* Subroutine of c_do_switch_warnings, called via splay_tree_foreach.
5413 Used to verify that case values match up with enumerator values. */
5415 static int
5417 {
5421 /* Skip default case. */
5425 /* If CASE_LOW_SEEN is not set, that means CASE_LOW did not appear
5426 when we did our enum->case scan. Reset our scratch bit after. */
5429 else
5432 /* If CASE_HIGH is non-null, we have a range. If CASE_HIGH_SEEN is
5433 not set, that means that CASE_HIGH did not appear when we did our
5434 enum->case scan. Reset our scratch bit after. */
5436 {
5439 else
5441 }
5444 }
5446 /* Handle -Wswitch*. Called from the front end after parsing the
5447 switch construct. */
5448 /* ??? Should probably be somewhere generic, since other languages
5449 besides C and C++ would want this. At the moment, however, C/C++
5450 are the only tree-ssa languages that support enumerations at all,
5451 so the point is moot. */
5453 void
5456 {
5457 splay_tree_node default_node;
5458 splay_tree_node node;
5459 tree chain;
5469 /* From here on, we only care about about enumerated types. */
5473 /* From here on, we only care about -Wswitch and -Wswitch-enum. */
5477 /* Check the cases. Warn about case values which are not members of
5478 the enumerated type. For -Wswitch-enum, or for -Wswitch when
5479 there is no default case, check that exactly all enumeration
5480 literals are covered by the cases. */
5482 /* Clearing COND if it is not an integer constant simplifies
5483 the tests inside the loop below. */
5487 /* The time complexity here is O(N*lg(N)) worst case, but for the
5488 common case of monotonically increasing enumerators, it is
5489 O(N), since the nature of the splay tree will keep the next
5490 element adjacent to the root at all times. */
5493 {
5499 {
5500 /* Mark the CASE_LOW part of the case entry as seen. */
5504 }
5506 /* Even though there wasn't an exact match, there might be a
5507 case range which includes the enumerator's value. */
5510 {
5514 {
5515 /* If we match the upper bound exactly, mark the CASE_HIGH
5516 part of the case entry as seen. */
5520 }
5521 }
5523 /* We've now determined that this enumerated literal isn't
5524 handled by the case labels of the switch statement. */
5526 /* If the switch expression is a constant, we only really care
5527 about whether that constant is handled by the switch. */
5531 /* If there is a default_node, the only relevant option is
5532 Wswitch-enum. Otherwise, if both are enabled then we prefer
5533 to warn using -Wswitch because -Wswitch is enabled by -Wall
5534 while -Wswitch-enum is explicit. */
5537 ? OPT_Wswitch_enum
5541 }
5543 /* Warn if there are case expressions that don't correspond to
5544 enumerators. This can occur since C and C++ don't enforce
5545 type-checking of assignments to enumeration variables.
5547 The time complexity here is now always O(N) worst case, since
5548 we should have marked both the lower bound and upper bound of
5549 every disjoint case label, with CASE_LOW_SEEN and CASE_HIGH_SEEN
5550 above. This scan also resets those fields. */
5553 }
5555 /* Finish an expression taking the address of LABEL (an
5556 IDENTIFIER_NODE). Returns an expression for the address.
5558 LOC is the location for the expression returned. */
5560 tree
5562 {
5563 tree result;
5573 else
5574 {
5577 /* The current function is not necessarily uninlinable.
5578 Computed gotos are incompatible with inlining, but the value
5579 here could be used only in a diagnostic, for example. */
5581 }
5584 }
5585 \f
5587 /* Given a boolean expression ARG, return a tree representing an increment
5588 or decrement (as indicated by CODE) of ARG. The front end must check for
5589 invalid cases (e.g., decrement in C++). */
5590 tree
5592 {
5593 tree val;
5598 {
5621 }
5624 }
5625 \f
5626 /* Built-in macros for stddef.h and stdint.h, that require macros
5627 defined in this file. */
5628 void
5630 {
5693 }
5695 static void
5697 {
5698 /* Fill in the built_in_attributes array. */
5699 #define DEF_ATTR_NULL_TREE(ENUM) \
5700 built_in_attributes[(int) ENUM] = NULL_TREE;
5701 #define DEF_ATTR_INT(ENUM, VALUE) \
5702 built_in_attributes[(int) ENUM] = build_int_cst (integer_type_node, VALUE);
5703 #define DEF_ATTR_IDENT(ENUM, STRING) \
5704 built_in_attributes[(int) ENUM] = get_identifier (STRING);
5705 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) \
5706 built_in_attributes[(int) ENUM] \
5707 = tree_cons (built_in_attributes[(int) PURPOSE], \
5708 built_in_attributes[(int) VALUE], \
5709 built_in_attributes[(int) CHAIN]);
5711 #undef DEF_ATTR_NULL_TREE
5712 #undef DEF_ATTR_INT
5713 #undef DEF_ATTR_IDENT
5714 #undef DEF_ATTR_TREE_LIST
5715 }
5717 /* Returns TRUE iff the attribute indicated by ATTR_ID takes a plain
5718 identifier as an argument, so the front end shouldn't look it up. */
5720 bool
5722 {
5725 /* Unknown attribute that we'll end up ignoring, return true so we
5726 don't complain about an identifier argument. */
5732 else
5734 }
5736 /* Attribute handlers common to C front ends. */
5738 /* Handle a "packed" attribute; arguments as in
5739 struct attribute_spec.handler. */
5741 static tree
5744 {
5746 {
5750 }
5752 {
5754 /* Still pack bitfields. */
5759 else
5761 }
5762 /* We can't set DECL_PACKED for a VAR_DECL, because the bit is
5763 used for DECL_REGISTER. It wouldn't mean anything anyway.
5764 We can't set DECL_PACKED on the type of a TYPE_DECL, because
5765 that changes what the typedef is typing. */
5766 else
5767 {
5770 }
5773 }
5775 /* Handle a "nocommon" attribute; arguments as in
5776 struct attribute_spec.handler. */
5778 static tree
5782 {
5785 else
5786 {
5789 }
5792 }
5794 /* Handle a "common" attribute; arguments as in
5795 struct attribute_spec.handler. */
5797 static tree
5800 {
5803 else
5804 {
5807 }
5810 }
5812 /* Handle a "noreturn" attribute; arguments as in
5813 struct attribute_spec.handler. */
5815 static tree
5818 {
5821 /* See FIXME comment in c_common_attribute_table. */
5828 = build_pointer_type
5831 else
5832 {
5835 }
5838 }
5840 /* Handle a "hot" and attribute; arguments as in
5841 struct attribute_spec.handler. */
5843 static tree
5846 {
5848 {
5850 {
5854 }
5855 /* Most of the rest of the hot processing is done later with
5856 lookup_attribute. */
5857 }
5858 else
5859 {
5862 }
5865 }
5866 /* Handle a "cold" and attribute; arguments as in
5867 struct attribute_spec.handler. */
5869 static tree
5872 {
5874 {
5876 {
5880 }
5881 /* Most of the rest of the cold processing is done later with
5882 lookup_attribute. */
5883 }
5884 else
5885 {
5888 }
5891 }
5893 /* Handle a "noinline" attribute; arguments as in
5894 struct attribute_spec.handler. */
5896 static tree
5900 {
5903 else
5904 {
5907 }
5910 }
5912 /* Handle a "noclone" attribute; arguments as in
5913 struct attribute_spec.handler. */
5915 static tree
5919 {
5921 {
5924 }
5927 }
5929 /* Handle a "always_inline" attribute; arguments as in
5930 struct attribute_spec.handler. */
5932 static tree
5937 {
5939 {
5940 /* Set the attribute and mark it for disregarding inline
5941 limits. */
5943 }
5944 else
5945 {
5948 }
5951 }
5953 /* Handle a "gnu_inline" attribute; arguments as in
5954 struct attribute_spec.handler. */
5956 static tree
5961 {
5963 {
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 "leaf" attribute; arguments as in
5977 struct attribute_spec.handler. */
5979 static tree
5983 {
5985 {
5988 }
5990 {
5993 }
5996 }
5998 /* Handle an "artificial" attribute; arguments as in
5999 struct attribute_spec.handler. */
6001 static tree
6006 {
6008 {
6009 /* Do nothing else, just set the attribute. We'll get at
6010 it later with lookup_attribute. */
6011 }
6012 else
6013 {
6016 }
6019 }
6021 /* Handle a "flatten" attribute; arguments as in
6022 struct attribute_spec.handler. */
6024 static tree
6026 tree args ATTRIBUTE_UNUSED,
6028 {
6030 /* Do nothing else, just set the attribute. We'll get at
6031 it later with lookup_attribute. */
6032 ;
6033 else
6034 {
6037 }
6040 }
6042 /* Handle a "warning" or "error" attribute; arguments as in
6043 struct attribute_spec.handler. */
6045 static tree
6048 {
6051 /* Do nothing else, just set the attribute. We'll get at
6052 it later with lookup_attribute. */
6053 ;
6054 else
6055 {
6058 }
6061 }
6063 /* Handle a "used" attribute; arguments as in
6064 struct attribute_spec.handler. */
6066 static tree
6069 {
6074 {
6079 }
6080 else
6081 {
6084 }
6087 }
6089 /* Handle a "unused" attribute; arguments as in
6090 struct attribute_spec.handler. */
6092 static tree
6095 {
6097 {
6105 {
6110 }
6111 else
6112 {
6115 }
6116 }
6117 else
6118 {
6122 }
6125 }
6127 /* Handle a "externally_visible" attribute; arguments as in
6128 struct attribute_spec.handler. */
6130 static tree
6135 {
6139 {
6142 {
6146 }
6147 }
6148 else
6149 {
6152 }
6155 }
6157 /* Handle a "const" attribute; arguments as in
6158 struct attribute_spec.handler. */
6160 static tree
6163 {
6166 /* See FIXME comment on noreturn in c_common_attribute_table. */
6172 = build_pointer_type
6175 else
6176 {
6179 }
6182 }
6184 /* Handle a "transparent_union" attribute; arguments as in
6185 struct attribute_spec.handler. */
6187 static tree
6191 {
6192 tree type;
6201 {
6202 /* When IN_PLACE is set, leave the check for FIELDS and MODE to
6203 the code in finish_struct. */
6205 {
6211 /* A type variant isn't good enough, since we don't a cast
6212 to such a type removed as a no-op. */
6214 }
6218 }
6220 ignored:
6223 }
6225 /* Subroutine of handle_{con,de}structor_attribute. Evaluate ARGS to
6226 get the requested priority for a constructor or destructor,
6227 possibly issuing diagnostics for invalid or reserved
6228 priorities. */
6230 static priority_type
6232 {
6233 HOST_WIDE_INT pri;
6234 tree arg;
6240 {
6243 else
6246 }
6258 {
6261 "destructor priorities from 0 to %d are reserved "
6263 MAX_RESERVED_INIT_PRIORITY);
6264 else
6266 "constructor priorities from 0 to %d are reserved "
6268 MAX_RESERVED_INIT_PRIORITY);
6269 }
6272 invalid:
6275 MAX_INIT_PRIORITY);
6276 else
6278 MAX_INIT_PRIORITY);
6280 }
6282 /* Handle a "constructor" attribute; arguments as in
6283 struct attribute_spec.handler. */
6285 static tree
6289 {
6296 {
6297 priority_type priority;
6302 }
6303 else
6304 {
6307 }
6310 }
6312 /* Handle a "destructor" attribute; arguments as in
6313 struct attribute_spec.handler. */
6315 static tree
6319 {
6326 {
6327 priority_type priority;
6332 }
6333 else
6334 {
6337 }
6340 }
6342 /* Nonzero if the mode is a valid vector mode for this architecture.
6343 This returns nonzero even if there is no hardware support for the
6344 vector mode, but we can emulate with narrower modes. */
6346 static int
6348 {
6352 /* Doh! What's going on? */
6361 /* Hardware support. Woo hoo! */
6367 /* We should probably return 1 if requesting V4DI and we have no DI,
6368 but we have V2DI, but this is probably very unlikely. */
6370 /* If we have support for the inner mode, we can safely emulate it.
6371 We may not have V2DI, but me can emulate with a pair of DIs. */
6373 }
6376 /* Handle a "mode" attribute; arguments as in
6377 struct attribute_spec.handler. */
6379 static tree
6382 {
6390 else
6391 {
6396 tree typefm;
6401 {
6407 }
6409 /* Change this type to have a type with the specified mode.
6410 First check for the special modes. */
6423 else
6426 {
6429 }
6432 {
6435 }
6439 {
6471 }
6473 {
6476 }
6479 {
6484 {
6487 }
6491 else
6494 }
6495 else
6496 {
6497 /* For fixed-point modes, we need to test if the signness of type
6498 and the machine mode are consistent. */
6501 {
6504 }
6505 /* For fixed-point modes, we need to pass saturating info. */
6509 }
6512 {
6515 }
6517 {
6518 /* For enumeral types, copy the precision from the integer
6519 type returned above. If not an INTEGER_TYPE, we can't use
6520 this mode for this type. */
6522 {
6525 }
6528 {
6531 }
6532 else
6533 {
6534 /* We cannot build a type variant, as there's code that assumes
6535 that TYPE_MAIN_VARIANT has the same mode. This includes the
6536 debug generators. Instead, create a subrange type. This
6537 results in all of the enumeral values being emitted only once
6538 in the original, and the subtype gets them by reference. */
6541 else
6544 }
6545 }
6549 {
6552 }
6555 }
6558 }
6560 /* Handle a "section" attribute; arguments as in
6561 struct attribute_spec.handler. */
6563 static tree
6566 {
6570 {
6576 {
6580 {
6582 "section attribute cannot be specified for "
6585 }
6587 /* The decl may have already been given a section attribute
6588 from a previous declaration. Ensure they match. */
6592 {
6596 }
6600 {
6603 }
6604 else
6606 }
6607 else
6608 {
6611 }
6612 }
6613 else
6614 {
6618 }
6621 }
6623 /* Handle a "aligned" attribute; arguments as in
6624 struct attribute_spec.handler. */
6626 static tree
6629 {
6638 {
6642 }
6647 {
6650 }
6652 {
6655 }
6657 {
6660 }
6662 {
6665 /* If we have a TYPE_DECL, then copy the type, so that we
6666 don't accidentally modify a builtin type. See pushdecl. */
6669 {
6676 }
6677 else
6682 }
6685 {
6688 }
6691 {
6696 else
6700 }
6701 else
6702 {
6705 }
6708 }
6710 /* Handle a "weak" attribute; arguments as in
6711 struct attribute_spec.handler. */
6713 static tree
6718 {
6721 {
6724 }
6726 {
6730 }
6734 else
6738 }
6740 /* Handle an "alias" or "ifunc" attribute; arguments as in
6741 struct attribute_spec.handler, except that IS_ALIAS tells us
6742 whether this is an alias as opposed to ifunc attribute. */
6744 static tree
6747 {
6752 {
6755 }
6759 /* A static variable declaration is always a tentative definition,
6760 but the alias is a non-tentative definition which overrides. */
6763 {
6767 }
6771 {
6775 }
6777 /* Note that the very first time we process a nested declaration,
6778 decl_function_context will not be set. Indeed, *would* never
6779 be set except for the DECL_INITIAL/DECL_EXTERNAL frobbery that
6780 we do below. After such frobbery, pushdecl would set the context.
6781 In any case, this is never what we want. */
6783 {
6784 tree id;
6788 {
6792 }
6794 /* This counts as a use of the object pointed to. */
6799 else
6800 {
6803 else
6806 }
6809 /* ifuncs are also aliases, so set that attribute too. */
6812 }
6813 else
6814 {
6817 }
6820 }
6822 /* Handle an "alias" or "ifunc" attribute; arguments as in
6823 struct attribute_spec.handler. */
6825 static tree
6828 {
6830 }
6832 /* Handle an "alias" or "ifunc" attribute; arguments as in
6833 struct attribute_spec.handler. */
6835 static tree
6838 {
6840 }
6842 /* Handle a "weakref" attribute; arguments as in struct
6843 attribute_spec.handler. */
6845 static tree
6848 {
6851 /* We must ignore the attribute when it is associated with
6852 local-scoped decls, since attribute alias is ignored and many
6853 such symbols do not even have a DECL_WEAK field. */
6855 || current_function_decl
6857 {
6861 }
6864 {
6868 }
6870 /* The idea here is that `weakref("name")' mutates into `weakref,
6871 alias("name")', and weakref without arguments, in turn,
6872 implicitly adds weak. */
6875 {
6882 }
6883 else
6884 {
6889 /* Can't call declare_weak because it wants this to be TREE_PUBLIC,
6890 and that isn't supported; and because it wants to add it to
6891 the list of weak decls, which isn't helpful. */
6893 }
6896 }
6898 /* Handle an "visibility" attribute; arguments as in
6899 struct attribute_spec.handler. */
6901 static tree
6905 {
6911 {
6915 {
6917 name);
6919 }
6921 {
6925 }
6926 }
6928 {
6931 }
6934 {
6937 }
6939 /* If this is a type, set the visibility on the type decl. */
6941 {
6946 {
6948 name);
6950 }
6951 }
6961 else
6962 {
6963 error ("visibility argument must be one of \"default\", \"hidden\", \"protected\" or \"internal\"");
6965 }
6969 {
6983 }
6988 /* Go ahead and attach the attribute to the node as well. This is needed
6989 so we can determine whether we have VISIBILITY_DEFAULT because the
6990 visibility was not specified, or because it was explicitly overridden
6991 from the containing scope. */
6994 }
6996 /* Determine the ELF symbol visibility for DECL, which is either a
6997 variable or a function. It is an error to use this function if a
6998 definition of DECL is not available in this translation unit.
6999 Returns true if the final visibility has been determined by this
7000 function; false if the caller is free to make additional
7001 modifications. */
7003 bool
7005 {
7009 /* If the user explicitly specified the visibility with an
7010 attribute, honor that. DECL_VISIBILITY will have been set during
7011 the processing of the attribute. We check for an explicit
7012 attribute, rather than just checking DECL_VISIBILITY_SPECIFIED,
7013 to distinguish the use of an attribute from the use of a "#pragma
7014 GCC visibility push(...)"; in the latter case we still want other
7015 considerations to be able to overrule the #pragma. */
7017 || (TARGET_DLLIMPORT_DECL_ATTRIBUTES
7022 /* Set default visibility to whatever the user supplied with
7023 visibility_specified depending on #pragma GCC visibility. */
7025 {
7028 {
7031 /* If visibility changed and DECL already has DECL_RTL, ensure
7032 symbol flags are updated. */
7037 }
7038 }
7040 }
7042 /* Handle an "tls_model" attribute; arguments as in
7043 struct attribute_spec.handler. */
7045 static tree
7048 {
7049 tree id;
7056 {
7059 }
7064 {
7067 }
7077 else
7078 error ("tls_model argument must be one of \"local-exec\", \"initial-exec\", \"local-dynamic\" or \"global-dynamic\"");
7082 }
7084 /* Handle a "no_instrument_function" attribute; arguments as in
7085 struct attribute_spec.handler. */
7087 static tree
7092 {
7096 {
7100 }
7102 {
7106 }
7107 else
7111 }
7113 /* Handle a "malloc" attribute; arguments as in
7114 struct attribute_spec.handler. */
7116 static tree
7119 {
7123 else
7124 {
7127 }
7130 }
7132 /* Handle a "alloc_size" attribute; arguments as in
7133 struct attribute_spec.handler. */
7135 static tree
7138 {
7141 {
7148 {
7153 }
7154 }
7156 }
7158 /* Handle a "fn spec" attribute; arguments as in
7159 struct attribute_spec.handler. */
7161 static tree
7165 {
7170 }
7172 /* Handle a "returns_twice" attribute; arguments as in
7173 struct attribute_spec.handler. */
7175 static tree
7178 {
7181 else
7182 {
7185 }
7188 }
7190 /* Handle a "no_limit_stack" attribute; arguments as in
7191 struct attribute_spec.handler. */
7193 static tree
7198 {
7202 {
7206 }
7208 {
7212 }
7213 else
7217 }
7219 /* Handle a "pure" attribute; arguments as in
7220 struct attribute_spec.handler. */
7222 static tree
7225 {
7228 /* ??? TODO: Support types. */
7229 else
7230 {
7233 }
7236 }
7238 /* Handle a "no vops" attribute; arguments as in
7239 struct attribute_spec.handler. */
7241 static tree
7245 {
7249 }
7251 /* Handle a "deprecated" attribute; arguments as in
7252 struct attribute_spec.handler. */
7254 static tree
7258 {
7266 {
7269 }
7272 {
7283 else
7285 }
7287 {
7292 }
7293 else
7297 {
7300 {
7306 }
7309 else
7311 }
7314 }
7316 /* Handle a "vector_size" attribute; arguments as in
7317 struct attribute_spec.handler. */
7319 static tree
7323 {
7333 {
7336 }
7338 /* Get the vector size (in bytes). */
7341 /* We need to provide for vector pointers, vector arrays, and
7342 functions returning vectors. For example:
7344 __attribute__((vector_size(16))) short *foo;
7346 In this case, the mode is SI, but the type being modified is
7347 HI, so we need to look further. */
7356 /* Get the mode of the type being modified. */
7367 {
7370 }
7373 {
7376 }
7379 {
7382 }
7384 /* Calculate how many units fit in the vector. */
7387 {
7390 }
7394 /* Build back pointers if needed. */
7398 }
7400 /* Handle the "nonnull" attribute. */
7401 static tree
7405 {
7409 /* If no arguments are specified, all pointer arguments should be
7410 non-null. Verify a full prototype is given so that the arguments
7411 will have the correct types when we actually check them later. */
7413 {
7415 {
7418 }
7420 }
7422 /* Argument list specified. Verify that each argument number references
7423 a pointer argument. */
7425 {
7429 {
7434 }
7437 {
7438 function_args_iterator iter;
7439 tree argument;
7443 {
7447 }
7451 {
7456 }
7459 {
7464 }
7465 }
7466 }
7469 }
7471 /* Check the argument list of a function call for null in argument slots
7472 that are marked as requiring a non-null pointer argument. The NARGS
7473 arguments are passed in the array ARGARRAY.
7474 */
7476 static void
7478 {
7483 {
7485 {
7488 /* Walk the argument list. If we encounter an argument number we
7489 should check for non-null, do it. If the attribute has no args,
7490 then every pointer argument is checked (in which case the check
7491 for pointer type is done in check_nonnull_arg). */
7493 {
7498 }
7499 }
7500 }
7501 }
7503 /* Check that the Nth argument of a function call (counting backwards
7504 from the end) is a (pointer)0. The NARGS arguments are passed in the
7505 array ARGARRAY. */
7507 static void
7509 {
7513 {
7516 tree sentinel;
7517 function_args_iterator iter;
7518 tree t;
7520 /* Skip over the named arguments. */
7522 {
7525 len++;
7526 }
7529 {
7532 }
7534 /* The sentinel must be one of the varargs, i.e.
7535 in position >= the number of fixed arguments. */
7537 {
7541 }
7543 /* Validate the sentinel. */
7547 /* Although __null (in C++) is only an integer we allow it
7548 nevertheless, as we are guaranteed that it's exactly
7549 as wide as a pointer, and we don't want to force
7550 users to cast the NULL they have written there.
7551 We warn with -Wstrict-null-sentinel, though. */
7554 }
7555 }
7557 /* Helper for check_function_nonnull; given a list of operands which
7558 must be non-null in ARGS, determine if operand PARAM_NUM should be
7559 checked. */
7561 static bool
7563 {
7567 {
7574 }
7576 }
7578 /* Check that the function argument PARAM (which is operand number
7579 PARAM_NUM) is non-null. This is called by check_function_nonnull
7580 via check_function_arguments_recurse. */
7582 static void
7585 {
7586 /* Just skip checking the argument if it's not a pointer. This can
7587 happen if the "nonnull" attribute was given without an operand
7588 list (which means to check every pointer argument). */
7596 }
7598 /* Helper for nonnull attribute handling; fetch the operand number
7599 from the attribute argument list. */
7601 static bool
7603 {
7604 /* Verify the arg number is a constant. */
7611 }
7613 /* Handle a "nothrow" attribute; arguments as in
7614 struct attribute_spec.handler. */
7616 static tree
7619 {
7622 /* ??? TODO: Support types. */
7623 else
7624 {
7627 }
7630 }
7632 /* Handle a "cleanup" attribute; arguments as in
7633 struct attribute_spec.handler. */
7635 static tree
7638 {
7642 /* ??? Could perhaps support cleanups on TREE_STATIC, much like we do
7643 for global destructors in C++. This requires infrastructure that
7644 we don't have generically at the moment. It's also not a feature
7645 we'd be missing too much, since we do have attribute constructor. */
7647 {
7651 }
7653 /* Verify that the argument is a function in scope. */
7654 /* ??? We could support pointers to functions here as well, if
7655 that was considered desirable. */
7658 {
7662 }
7665 {
7669 }
7671 /* That the function has proper type is checked with the
7672 eventual call to build_function_call. */
7675 }
7677 /* Handle a "warn_unused_result" attribute. No special handling. */
7679 static tree
7683 {
7684 /* Ignore the attribute for functions not returning any value. */
7686 {
7689 }
7692 }
7694 /* Handle a "sentinel" attribute. */
7696 static tree
7699 {
7701 {
7705 }
7706 else
7707 {
7709 {
7713 }
7714 }
7717 {
7721 {
7725 }
7726 else
7727 {
7729 {
7733 }
7734 }
7735 }
7738 }
7740 /* Handle a "type_generic" attribute. */
7742 static tree
7746 {
7747 /* Ensure we have a function type. */
7750 /* Ensure we have a variadic function. */
7754 }
7756 /* Handle a "target" attribute. */
7758 static tree
7761 {
7762 /* Ensure we have a function type. */
7764 {
7767 }
7769 flags))
7773 }
7775 /* Arguments being collected for optimization. */
7782 /* Inner function to convert a TREE_LIST to argv string to parse the optimize
7783 options in ARGS. ATTR_P is true if this is for attribute(optimize), and
7784 false for #pragma GCC optimize. */
7786 bool
7788 {
7796 tree ap;
7798 /* Build up argv vector. Just in case the string is stored away, use garbage
7799 collected strings. */
7804 {
7808 {
7812 }
7815 {
7816 /* Split string into multiple substrings. */
7824 {
7831 {
7835 }
7836 else
7837 {
7840 }
7844 /* If the user supplied -Oxxx or -fxxx, only allow -Oxxx or -fxxx
7845 options. */
7847 {
7852 else
7856 }
7859 {
7862 /* Assume that Ox is -Ox, a numeric value is -Ox, a s by
7863 itself is -Os, and any other switch begins with a -f. */
7869 }
7874 }
7876 }
7877 }
7887 /* Now parse the options. */
7897 /* Don't allow changing -fstrict-aliasing. */
7902 }
7904 /* For handling "optimize" attribute. arguments as in
7905 struct attribute_spec.handler. */
7907 static tree
7910 {
7911 /* Ensure we have a function type. */
7913 {
7916 }
7917 else
7918 {
7922 /* Save current options. */
7925 /* If we previously had some optimization options, use them as the
7926 default. */
7931 /* Parse options, and update the vector. */
7936 /* Restore current options. */
7938 }
7941 }
7943 /* Handle a "no_split_stack" attribute. */
7945 static tree
7950 {
7954 {
7958 }
7960 {
7964 }
7967 }
7968 \f
7969 /* Check for valid arguments being passed to a function with FNTYPE.
7970 There are NARGS arguments in the array ARGARRAY. */
7971 void
7973 {
7974 /* Check for null being passed in a pointer argument that must be
7975 non-null. We also need to do this if format checking is enabled. */
7980 /* Check for errors in format strings. */
7987 }
7989 /* Generic argument checking recursion routine. PARAM is the argument to
7990 be checked. PARAM_NUM is the number of the argument. CALLBACK is invoked
7991 once the argument is resolved. CTX is context for the callback. */
7992 void
7997 {
8001 {
8002 /* Strip coercion. */
8006 }
8009 {
8011 tree attrs;
8014 /* See if this is a call to a known internationalization function
8015 that modifies a format arg. Such a function may have multiple
8016 format_arg attributes (for example, ngettext). */
8019 attrs;
8022 {
8023 tree inner_arg;
8024 tree format_num_expr;
8027 call_expr_arg_iterator iter;
8029 /* Extract the argument number, which was previously checked
8030 to be valid. */
8042 {
8047 }
8048 }
8050 /* If we found a format_arg attribute and did a recursive check,
8051 we are done with checking this argument. Otherwise, we continue
8052 and this will be considered a non-literal. */
8055 }
8058 {
8059 /* Check both halves of the conditional expression. */
8065 }
8068 }
8070 /* Checks for a builtin function FNDECL that the number of arguments
8071 NARGS against the required number REQUIRED and issues an error if
8072 there is a mismatch. Returns true if the number of arguments is
8073 correct, otherwise false. */
8075 static bool
8077 {
8079 {
8083 }
8085 {
8089 }
8091 }
8093 /* Verifies the NARGS arguments ARGS to the builtin function FNDECL.
8094 Returns false if there was an error, otherwise true. */
8096 bool
8098 {
8104 {
8114 {
8116 {
8120 }
8122 }
8132 {
8139 {
8143 }
8145 }
8150 {
8155 {
8159 }
8162 {
8164 fndecl);
8166 }
8168 }
8173 }
8174 }
8176 /* Function to help qsort sort FIELD_DECLs by name order. */
8178 int
8180 {
8185 /* A nontype is "greater" than a type. */
8194 }
8197 gt_pointer_operator new_value;
8201 /* This routine compares two fields like field_decl_cmp but using the
8202 pointer operator in resort_data. */
8204 static int
8206 {
8211 /* A nontype is "greater" than a type. */
8217 {
8224 }
8226 }
8228 /* Resort DECL_SORTED_FIELDS because pointers have been reordered. */
8230 void
8233 gt_pointer_operator new_value,
8235 {
8240 resort_field_decl_cmp);
8241 }
8243 /* Subroutine of c_parse_error.
8244 Return the result of concatenating LHS and RHS. RHS is really
8245 a string literal, its first character is indicated by RHS_START and
8246 RHS_SIZE is its length (including the terminating NUL character).
8248 The caller is responsible for deleting the returned pointer. */
8252 {
8258 }
8260 /* Issue the error given by GMSGID, indicating that it occurred before
8261 TOKEN, which had the associated VALUE. */
8263 void
8266 {
8267 #define catenate_messages(M1, M2) catenate_strings ((M1), (M2), sizeof (M2))
8277 {
8282 {
8295 }
8299 else
8305 }
8315 {
8320 }
8326 {
8331 }
8332 else
8336 {
8339 }
8340 #undef catenate_messages
8341 }
8343 /* Mapping for cpp message reasons to the options that enable them. */
8345 struct reason_option_codes_t
8346 {
8349 };
8368 };
8370 /* Return the gcc option code associated with the reason for a cpp
8371 message, or 0 if none. */
8373 static int
8375 {
8379 {
8382 }
8384 }
8386 /* Callback from cpp_error for PFILE to print diagnostics from the
8387 preprocessor. The diagnostic is of type LEVEL, with REASON set
8388 to the reason code if LEVEL is represents a warning, at location
8389 LOCATION unless this is after lexing and the compiler's location
8390 should be used instead, with column number possibly overridden by
8391 COLUMN_OVERRIDE if not zero; MSG is the translated message and AP
8392 the arguments. Returns true if a diagnostic was emitted, false
8393 otherwise. */
8395 bool
8399 {
8400 diagnostic_info diagnostic;
8401 diagnostic_t dlevel;
8406 {
8411 /* Fall through. */
8436 }
8449 }
8451 /* Convert a character from the host to the target execution character
8452 set. cpplib handles this, mostly. */
8454 HOST_WIDE_INT
8456 {
8457 /* Character constants in GCC proper are sign-extended under -fsigned-char,
8458 zero-extended under -fno-signed-char. cpplib insists that characters
8459 and character constants are always unsigned. Hence we must convert
8460 back and forth. */
8468 else
8470 }
8472 /* Build the result of __builtin_offsetof. EXPR is a nested sequence of
8473 component references, with STOP_REF, or alternatively an INDIRECT_REF of
8474 NULL, at the bottom; much like the traditional rendering of offsetof as a
8475 macro. Returns the folded and properly cast result. */
8477 static tree
8479 {
8487 {
8503 {
8506 }
8516 {
8520 }
8534 {
8537 }
8541 /* Check if the offset goes beyond the upper bound of the array. */
8543 {
8549 {
8553 {
8554 tree v;
8561 {
8569 }
8570 /* Don't warn if the array might be considered a poor
8571 man's flexible array member with a very permissive
8572 definition thereof. */
8576 "index %E denotes an offset "
8579 }
8580 }
8581 }
8585 /* Handle static members of volatile structs. */
8592 }
8595 }
8597 tree
8599 {
8600 /* Convert back from the internal sizetype to size_t. */
8602 }
8604 /* Warn for A ?: C expressions (with B omitted) where A is a boolean
8605 expression, because B will always be true. */
8607 void
8609 {
8612 "the omitted middle operand in ?: will always be %<true%>, "
8614 }
8616 /* Give an error for storing into ARG, which is 'const'. USE indicates
8617 how ARG was being used. */
8619 void
8621 {
8624 /* Using this macro rather than (for example) arrays of messages
8625 ensures that all the format strings are checked at compile
8626 time. */
8627 #define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \
8628 : (use == lv_increment ? (I) \
8629 : (use == lv_decrement ? (D) : (AS))))
8631 {
8642 else
8648 }
8654 arg);
8660 arg);
8662 {
8672 arg);
8673 }
8679 arg);
8680 else
8685 arg);
8686 }
8688 /* Print an error message for an invalid lvalue. USE says
8689 how the lvalue is being used and so selects the error message. LOC
8690 is the location for the error. */
8692 void
8694 {
8696 {
8714 }
8715 }
8717 /* Print an error message for an invalid indirection of type TYPE.
8718 ERRSTRING is the name of the operator for the indirection. */
8720 void
8722 {
8724 {
8732 type);
8737 type);
8742 type);
8747 type);
8751 }
8752 }
8753 \f
8754 /* *PTYPE is an incomplete array. Complete it with a domain based on
8755 INITIAL_VALUE. If INITIAL_VALUE is not present, use 1 if DO_DEFAULT
8756 is true. Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
8757 2 if INITIAL_VALUE was NULL, and 3 if INITIAL_VALUE was empty. */
8759 int
8761 {
8768 {
8770 {
8771 int eltsize
8774 }
8776 {
8780 {
8784 }
8785 else
8786 {
8787 tree curindex;
8800 cnt++)
8801 {
8805 else
8806 {
8810 size_one_node);
8811 }
8814 }
8817 }
8818 }
8819 else
8820 {
8821 /* Make an error message unless that happened already. */
8824 }
8825 }
8826 else
8827 {
8831 }
8838 else
8841 /* Using build_distinct_type_copy and modifying things afterward instead
8842 of using build_array_type to create a new type preserves all of the
8843 TYPE_LANG_FLAG_? bits that the front end may have set. */
8851 /* Make sure we have the canonical MAIN_TYPE. */
8854 hashcode);
8857 /* Fix the canonical type. */
8867 else
8872 else
8878 {
8880 /* If we proceed with the array type as it is, we'll eventually
8881 crash in tree_low_cst(). */
8883 }
8887 }
8889 /* Like c_mark_addressable but don't check register qualifier. */
8890 void
8892 {
8898 }
8901 \f
8902 /* Used to help initialize the builtin-types.def table. When a type of
8903 the correct size doesn't exist, use error_mark_node instead of NULL.
8904 The later results in segfaults even when a decl using the type doesn't
8905 get invoked. */
8907 tree
8909 {
8912 }
8914 /* A helper function for resolve_overloaded_builtin in resolving the
8915 overloaded __sync_ builtins. Returns a positive power of 2 if the
8916 first operand of PARAMS is a pointer to a supported data type.
8917 Returns 0 if an error is encountered. */
8919 static int
8921 {
8922 tree type;
8926 {
8929 }
8943 incompatible:
8946 }
8948 /* A helper function for resolve_overloaded_builtin. Adds casts to
8949 PARAMS to make arguments match up with those of FUNCTION. Drops
8950 the variadic arguments at the end. Returns false if some error
8951 was encountered; true on success. */
8953 static bool
8955 {
8956 function_args_iterator iter;
8957 tree ptype;
8961 /* We've declared the implementation functions to use "volatile void *"
8962 as the pointer parameter, so we shouldn't get any complaints from the
8963 call to check_function_arguments what ever type the user used. */
8967 /* For the rest of the values, we need to cast these to FTYPE, so that we
8968 don't get warnings for passing pointer types, etc. */
8971 {
8975 /* XXX void_type_node belies the abstraction. */
8981 {
8984 }
8986 /* ??? Ideally for the first conversion we'd use convert_for_assignment
8987 so that we get warnings for anything that doesn't match the pointer
8988 type. This isn't portable across the C and C++ front ends atm. */
8995 }
8997 /* The definition of these primitives is variadic, with the remaining
8998 being "an optional list of variables protected by the memory barrier".
8999 No clue what that's supposed to mean, precisely, but we consider all
9000 call-clobbered variables to be protected so we're safe. */
9004 }
9006 /* A helper function for resolve_overloaded_builtin. Adds a cast to
9007 RESULT to make it match the type of the first pointer argument in
9008 PARAMS. */
9010 static tree
9012 {
9016 }
9018 /* Some builtin functions are placeholders for other expressions. This
9019 function should be called immediately after parsing the call expression
9020 before surrounding code has committed to the type of the expression.
9022 LOC is the location of the builtin call.
9024 FUNCTION is the DECL that has been invoked; it is known to be a builtin.
9025 PARAMS is the argument list for the call. The return value is non-null
9026 when expansion is complete, and null if normal processing should
9027 continue. */
9029 tree
9031 {
9034 {
9040 else
9044 }
9046 /* Handle BUILT_IN_NORMAL here. */
9048 {
9065 {
9083 }
9087 }
9088 }
9090 /* Ignoring their sign, return true if two scalar types are the same. */
9091 bool
9093 {
9100 /* Equality works here because c_common_signed_type uses
9101 TYPE_MAIN_VARIANT. */
9104 }
9106 /* Check for missing format attributes on function pointers. LTYPE is
9107 the new type or left-hand side type. RTYPE is the old type or
9108 right-hand side type. Returns TRUE if LTYPE is missing the desired
9109 attribute. */
9111 bool
9113 {
9115 tree ra;
9121 {
9122 tree la;
9127 }
9128 else
9130 }
9132 /* Subscripting with type char is likely to lose on a machine where
9133 chars are signed. So warn on any machine, but optionally. Don't
9134 warn for unsigned char since that type is safe. Don't warn for
9135 signed char because anyone who uses that must have done so
9136 deliberately. Furthermore, we reduce the false positive load by
9137 warning only for non-constant value of type char. */
9139 void
9141 {
9145 }
9147 /* Implement -Wparentheses for the unexpected C precedence rules, to
9148 cover cases like x + y << z which readers are likely to
9149 misinterpret. We have seen an expression in which CODE is a binary
9150 operator used to combine expressions ARG_LEFT and ARG_RIGHT, which
9151 before folding had CODE_LEFT and CODE_RIGHT. CODE_LEFT and
9152 CODE_RIGHT may be ERROR_MARK, which means that that side of the
9153 expression was not formed using a binary or unary operator, or it
9154 was enclosed in parentheses. */
9156 void
9160 {
9164 /* This macro tests that the expression ARG with original tree code
9165 CODE appears to be a boolean expression. or the result of folding a
9166 boolean expression. */
9167 #define APPEARS_TO_BE_BOOLEAN_EXPR_P(CODE, ARG) \
9168 (truth_value_p (TREE_CODE (ARG)) \
9169 || TREE_CODE (TREE_TYPE (ARG)) == BOOLEAN_TYPE \
9171 || ((CODE) != INTEGER_CST \
9172 && (integer_onep (ARG) || integer_zerop (ARG))))
9175 {
9207 /* Check cases like x|y==z */
9212 /* Check cases like !x | y */
9226 /* Check cases like x^y==z */
9240 /* Check cases like x&y==z */
9245 /* Check cases like !x & y */
9276 }
9277 #undef NOT_A_BOOLEAN_EXPR_P
9278 }
9280 /* If LABEL (a LABEL_DECL) has not been used, issue a warning. */
9282 void
9284 {
9286 {
9289 else
9291 }
9292 }
9294 /* Warn for division by zero according to the value of DIVISOR. LOC
9295 is the location of the division operator. */
9297 void
9299 {
9300 /* If DIVISOR is zero, and has integral or fixed-point type, issue a warning
9301 about division by zero. Do not issue a warning if DIVISOR has a
9302 floating-point type, since we consider 0.0/0.0 a valid way of
9303 generating a NaN. */
9307 }
9309 /* Subroutine of build_binary_op. Give warnings for comparisons
9310 between signed and unsigned quantities that may fail. Do the
9311 checking based on the original operand trees ORIG_OP0 and ORIG_OP1,
9312 so that casts will be considered, but default promotions won't
9313 be.
9315 LOCATION is the location of the comparison operator.
9317 The arguments of this function map directly to local variables
9318 of build_binary_op. */
9320 void
9325 {
9330 /* In C++, check for comparison of different enum types. */
9336 {
9340 }
9342 /* Do not warn if the comparison is being done in a signed type,
9343 since the signed type will only be chosen if it can represent
9344 all the values of the unsigned type. */
9347 /* Do not warn if both operands are unsigned. */
9350 else
9351 {
9357 else
9365 /* Do not warn if the signed quantity is an unsuffixed integer
9366 literal (or some static constant expression involving such
9367 literals or a conditional expression involving such literals)
9368 and it is non-negative. */
9371 /* Do not warn if the comparison is an equality operation, the
9372 unsigned quantity is an integral constant, and it would fit
9373 in the result if the result were signed. */
9378 /* In C, do not warn if the unsigned quantity is an enumeration
9379 constant and its maximum value would fit in the result if the
9380 result were signed. */
9386 else
9388 OPT_Wsign_compare,
9390 }
9392 /* Warn if two unsigned values are being compared in a size larger
9393 than their original size, and one (and only one) is the result of
9394 a `~' operator. This comparison will always fail.
9396 Also warn if one operand is a constant, and the constant does not
9397 have all bits set that are set in the ~ operand when it is
9398 extended. */
9405 {
9412 {
9413 tree primop;
9419 {
9423 }
9424 else
9425 {
9429 }
9434 {
9437 {
9441 else
9444 }
9445 }
9446 }
9454 }
9455 }
9457 /* RESULT_TYPE is the result of converting TYPE1 and TYPE2 to a common
9458 type via c_common_type. If -Wdouble-promotion is in use, and the
9459 conditions for warning have been met, issue a warning. GMSGID is
9460 the warning message. It must have two %T specifiers for the type
9461 that was converted (generally "float") and the type to which it was
9462 converted (generally "double), respectively. LOC is the location
9463 to which the awrning should refer. */
9465 void
9468 {
9469 tree source_type;
9473 /* If the conversion will not occur at run-time, there is no need to
9474 warn about it. */
9486 else
9489 }
9491 /* Setup a TYPE_DECL node as a typedef representation.
9493 X is a TYPE_DECL for a typedef statement. Create a brand new
9494 ..._TYPE node (which will be just a variant of the existing
9495 ..._TYPE node with identical properties) and then install X
9496 as the TYPE_NAME of this brand new (duplicate) ..._TYPE node.
9498 The whole point here is to end up with a situation where each
9499 and every ..._TYPE node the compiler creates will be uniquely
9500 associated with AT MOST one node representing a typedef name.
9501 This way, even though the compiler substitutes corresponding
9502 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
9503 early on, later parts of the compiler can always do the reverse
9504 translation and get back the corresponding typedef name. For
9505 example, given:
9507 typedef struct S MY_TYPE;
9508 MY_TYPE object;
9510 Later parts of the compiler might only know that `object' was of
9511 type `struct S' if it were not for code just below. With this
9512 code however, later parts of the compiler see something like:
9514 struct S' == struct S
9515 typedef struct S' MY_TYPE;
9516 struct S' object;
9518 And they can then deduce (from the node for type struct S') that
9519 the original object declaration was:
9521 MY_TYPE object;
9523 Being able to do this is important for proper support of protoize,
9524 and also for generating precise symbolic debugging information
9525 which takes full account of the programmer's (typedef) vocabulary.
9527 Obviously, we don't want to generate a duplicate ..._TYPE node if
9528 the TYPE_DECL node that we are now processing really represents a
9529 standard built-in type. */
9531 void
9533 {
9537 {
9540 }
9543 {
9551 }
9552 }
9554 /* Record the types used by the current global variable declaration
9555 being parsed, so that we can decide later to emit their debug info.
9556 Those types are in types_used_by_cur_var_decl, and we are going to
9557 store them in the types_used_by_vars_hash hash table.
9558 DECL is the declaration of the global variable that has been parsed. */
9560 void
9562 {
9566 {
9569 }
9570 }
9572 /* The C and C++ parsers both use vectors to hold function arguments.
9573 For efficiency, we keep a cache of unused vectors. This is the
9574 cache. */
9581 /* Return a new vector from the cache. If the cache is empty,
9582 allocate a new vector. These vectors are GC'ed, so it is OK if the
9583 pointer is not released.. */
9587 {
9590 else
9591 {
9592 /* Passing 0 to VEC_alloc returns NULL, and our callers require
9593 that we always return a non-NULL value. The vector code uses
9594 4 when growing a NULL vector, so we do too. */
9596 }
9597 }
9599 /* Release a vector of trees back to the cache. */
9601 void
9603 {
9605 {
9608 }
9609 }
9611 /* Get a new tree vector holding a single tree. */
9615 {
9619 }
9621 /* Get a new tree vector of the TREE_VALUEs of a TREE_LIST chain. */
9625 {
9630 }
9632 /* Get a new tree vector which is a copy of an existing one. */
9636 {
9639 tree t;
9646 }
9648 /* Return true if KEYWORD starts a type specifier. */
9650 bool
9652 {
9654 {
9684 }
9685 }
9687 /* Return true if KEYWORD names a type qualifier. */
9689 bool
9691 {
9693 {
9700 }
9701 }
9703 /* Return true if KEYWORD names a storage class specifier.
9705 RID_TYPEDEF is not included in this list despite `typedef' being
9706 listed in C99 6.7.1.1. 6.7.1.3 indicates that `typedef' is listed as
9707 such for syntactic convenience only. */
9709 bool
9711 {
9713 {
9723 }
9724 }
9726 /* Return true if KEYWORD names a function-specifier [dcl.fct.spec]. */
9728 static bool
9730 {
9732 {
9739 }
9740 }
9742 /* Return true if KEYWORD names a decl-specifier [dcl.spec] or a
9743 declaration-specifier (C99 6.7). */
9745 bool
9747 {
9754 {
9761 }
9762 }
9764 /* Initialize language-specific-bits of tree_contains_struct. */
9766 void
9768 {
9771 }