| blob | ddb6d39774f95bf6724aaca87d9fff9fa3061d20 |
1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987-2013 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
21 /* This file is part of the C front end.
22 It contains routines to build C expressions given their operands,
23 including computing the types of the result, C-specific error checks,
24 and some optimization. */
43 /* Possible cases of implicit bad conversions. Used to select
44 diagnostic messages in convert_for_assignment. */
46 ic_argpass,
47 ic_assign,
48 ic_init,
49 ic_return
50 };
52 /* The level of nesting inside "__alignof__". */
55 /* The level of nesting inside "sizeof". */
58 /* The level of nesting inside "typeof". */
61 /* The argument of last parsed sizeof expression, only to be tested
62 if expr.original_code == SIZEOF_EXPR. */
63 tree c_last_sizeof_arg;
65 /* Nonzero if we've already printed a "missing braces around initializer"
66 message within this initializer. */
106 \f
107 /* Return true if EXP is a null pointer constant, false otherwise. */
109 static bool
111 {
112 /* This should really operate on c_expr structures, but they aren't
113 yet available everywhere required. */
122 }
124 /* EXPR may appear in an unevaluated part of an integer constant
125 expression, but not in an evaluated part. Wrap it in a
126 C_MAYBE_CONST_EXPR, or mark it with TREE_OVERFLOW if it is just an
127 INTEGER_CST and we cannot create a C_MAYBE_CONST_EXPR. */
129 static tree
131 {
132 tree ret;
134 {
137 }
138 else
139 {
142 }
144 }
146 /* Having checked whether EXPR may appear in an unevaluated part of an
147 integer constant expression and found that it may, remove any
148 C_MAYBE_CONST_EXPR noting this fact and return the resulting
149 expression. */
153 {
156 else
158 }
164 const_tree t1;
165 const_tree t2;
166 /* The return value of tagged_types_tu_compatible_p if we had seen
167 these two types already. */
169 };
174 /* Do `exp = require_complete_type (exp);' to make sure exp
175 does not have an incomplete type. (That includes void types.) */
177 tree
179 {
185 /* First, detect a valid value with a complete type. */
191 }
193 /* Print an error message for invalid use of an incomplete type.
194 VALUE is the expression that was used (or 0 if that isn't known)
195 and TYPE is the type that was invalid. */
197 void
199 {
202 /* Avoid duplicate error message. */
209 else
210 {
211 retry:
212 /* We must print an error message. Be clever about what it says. */
215 {
234 {
236 {
239 }
242 }
248 }
253 else
254 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
256 }
257 }
259 /* Given a type, apply default promotions wrt unnamed function
260 arguments and return the new type. */
262 tree
264 {
269 {
270 /* Preserve unsignedness if not really getting any wider. */
275 }
278 }
280 /* Return true if between two named address spaces, whether there is a superset
281 named address space that encompasses both address spaces. If there is a
282 superset, return which address space is the superset. */
284 static bool
286 {
288 {
291 }
293 {
296 }
298 {
301 }
302 else
304 }
306 /* Return a variant of TYPE which has all the type qualifiers of LIKE
307 as well as those of TYPE. */
309 static tree
311 {
314 addr_space_t as_common;
316 /* If the two named address spaces are different, determine the common
317 superset address space. If there isn't one, raise an error. */
319 {
323 }
329 }
331 /* Return true iff the given tree T is a variable length array. */
333 bool
335 {
340 }
341 \f
342 /* Return the composite type of two compatible types.
344 We assume that comptypes has already been done and returned
345 nonzero; if that isn't so, this may crash. In particular, we
346 assume that qualifiers match. */
348 tree
350 {
353 tree attributes;
355 /* Save time if the two types are the same. */
359 /* If one type is nonsense, use the other. */
368 /* Merge the attributes. */
371 /* If one is an enumerated type and the other is the compatible
372 integer type, the composite type might be either of the two
373 (DR#013 question 3). For consistency, use the enumerated type as
374 the composite type. */
384 {
386 /* For two pointers, do this recursively on the target type. */
387 {
394 }
397 {
400 tree unqual_elt;
407 /* We should not have any type quals on arrays at all. */
417 d1_variable = (!d1_zero
420 d2_variable = (!d2_zero
426 /* Save space: see if the result is identical to one of the args. */
439 /* Merge the element types, and have a size if either arg has
440 one. We may have qualifiers on the element types. To set
441 up TYPE_MAIN_VARIANT correctly, we need to form the
442 composite of the unqualified types and add the qualifiers
443 back at the end. */
448 && (d2_variable
449 || d2_zero
451 ? t1
453 /* Ensure a composite type involving a zero-length array type
454 is a zero-length type not an incomplete type. */
458 {
461 }
464 }
470 {
471 /* Try harder not to create a new aggregate type. */
476 }
480 /* Function types: prefer the one that specified arg types.
481 If both do, merge the arg types. Also merge the return types. */
482 {
490 /* Save space: see if the result is identical to one of the args. */
496 /* Simple way if one arg fails to specify argument types. */
498 {
502 }
504 {
508 }
510 /* If both args specify argument types, we must merge the two
511 lists, argument by argument. */
523 {
524 /* A null type means arg type is not specified.
525 Take whatever the other function type has. */
527 {
530 }
532 {
535 }
537 /* Given wait (union {union wait *u; int *i} *)
538 and wait (union wait *),
539 prefer union wait * as type of parm. */
542 {
543 tree memb;
550 {
556 {
562 }
563 }
564 }
567 {
568 tree memb;
575 {
581 {
587 }
588 }
589 }
591 parm_done: ;
592 }
596 /* ... falls through ... */
597 }
601 }
603 }
605 /* Return the type of a conditional expression between pointers to
606 possibly differently qualified versions of compatible types.
608 We assume that comp_target_types has already been done and returned
609 nonzero; if that isn't so, this may crash. */
611 static tree
613 {
614 tree attributes;
617 tree target;
622 /* Save time if the two types are the same. */
626 /* If one type is nonsense, use the other. */
635 /* Merge the attributes. */
638 /* Find the composite type of the target types, and combine the
639 qualifiers of the two types' targets. Do not lose qualifiers on
640 array element types by taking the TYPE_MAIN_VARIANT. */
649 /* For function types do not merge const qualifiers, but drop them
650 if used inconsistently. The middle-end uses these to mark const
651 and noreturn functions. */
657 else
660 /* If the two named address spaces are different, determine the common
661 superset address space. This is guaranteed to exist due to the
662 assumption that comp_target_type returned non-zero. */
672 }
674 /* Return the common type for two arithmetic types under the usual
675 arithmetic conversions. The default conversions have already been
676 applied, and enumerated types converted to their compatible integer
677 types. The resulting type is unqualified and has no attributes.
679 This is the type for the result of most arithmetic operations
680 if the operands have the given two types. */
682 static tree
684 {
688 /* If one type is nonsense, use the other. */
706 /* Save time if the two types are the same. */
720 /* When one operand is a decimal float type, the other operand cannot be
721 a generic float type or a complex type. We also disallow vector types
722 here. */
725 {
727 {
730 }
732 {
735 }
737 {
740 }
741 }
743 /* If one type is a vector type, return that type. (How the usual
744 arithmetic conversions apply to the vector types extension is not
745 precisely specified.) */
752 /* If one type is complex, form the common type of the non-complex
753 components, then make that complex. Use T1 or T2 if it is the
754 required type. */
756 {
765 else
767 }
769 /* If only one is real, use it as the result. */
777 /* If both are real and either are decimal floating point types, use
778 the decimal floating point type with the greater precision. */
781 {
791 }
793 /* Deal with fixed-point types. */
795 {
803 /* If one input type is saturating, the result type is saturating. */
807 /* If both fixed-point types are unsigned, the result type is unsigned.
808 When mixing fixed-point and integer types, follow the sign of the
809 fixed-point type.
810 Otherwise, the result type is signed. */
819 /* The result type is signed. */
821 {
822 /* If the input type is unsigned, we need to convert to the
823 signed type. */
825 {
831 else
834 }
836 {
842 else
845 }
846 }
849 {
852 }
853 else
854 {
856 /* Signed integers need to subtract one sign bit. */
858 }
861 {
864 }
865 else
866 {
868 /* Signed integers need to subtract one sign bit. */
870 }
875 satp);
876 }
878 /* Both real or both integers; use the one with greater precision. */
885 /* Same precision. Prefer long longs to longs to ints when the
886 same precision, following the C99 rules on integer type rank
887 (which are equivalent to the C90 rules for C90 types). */
895 {
898 else
900 }
908 {
909 /* But preserve unsignedness from the other type,
910 since long cannot hold all the values of an unsigned int. */
913 else
915 }
917 /* Likewise, prefer long double to double even if same size. */
922 /* Otherwise prefer the unsigned one. */
926 else
928 }
929 \f
930 /* Wrapper around c_common_type that is used by c-common.c and other
931 front end optimizations that remove promotions. ENUMERAL_TYPEs
932 are allowed here and are converted to their compatible integer types.
933 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or
934 preferably a non-Boolean type as the common type. */
935 tree
937 {
943 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */
948 /* If either type is BOOLEAN_TYPE, then return the other. */
955 }
957 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
958 or various other operations. Return 2 if they are compatible
959 but a warning may be needed if you use them together. */
961 int
963 {
971 }
973 /* Like comptypes, but if it returns non-zero because enum and int are
974 compatible, it sets *ENUM_AND_INT_P to true. */
976 static int
978 {
986 }
988 /* Like comptypes, but if it returns nonzero for different types, it
989 sets *DIFFERENT_TYPES_P to true. */
991 int
994 {
1002 }
1003 \f
1004 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
1005 or various other operations. Return 2 if they are compatible
1006 but a warning may be needed if you use them together. If
1007 ENUM_AND_INT_P is not NULL, and one type is an enum and the other a
1008 compatible integer type, then this sets *ENUM_AND_INT_P to true;
1009 *ENUM_AND_INT_P is never set to false. If DIFFERENT_TYPES_P is not
1010 NULL, and the types are compatible but different enough not to be
1011 permitted in C11 typedef redeclarations, then this sets
1012 *DIFFERENT_TYPES_P to true; *DIFFERENT_TYPES_P is never set to
1013 false, but may or may not be set if the types are incompatible.
1014 This differs from comptypes, in that we don't free the seen
1015 types. */
1017 static int
1020 {
1025 /* Suppress errors caused by previously reported errors. */
1031 /* Enumerated types are compatible with integer types, but this is
1032 not transitive: two enumerated types in the same translation unit
1033 are compatible with each other only if they are the same type. */
1036 {
1039 {
1044 }
1045 }
1047 {
1050 {
1055 }
1056 }
1061 /* Different classes of types can't be compatible. */
1066 /* Qualifiers must match. C99 6.7.3p9 */
1071 /* Allow for two different type nodes which have essentially the same
1072 definition. Note that we already checked for equality of the type
1073 qualifiers (just above). */
1079 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1083 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1087 {
1089 /* Do not remove mode or aliasing information. */
1100 different_types_p);
1104 {
1111 /* Target types must match incl. qualifiers. */
1114 enum_and_int_p,
1115 different_types_p)))
1121 /* Sizes must match unless one is missing or variable. */
1128 d1_variable = (!d1_zero
1131 d2_variable = (!d2_zero
1150 }
1156 {
1166 different_types_p);
1168 different_types_p);
1169 }
1180 }
1182 }
1184 /* Return 1 if TTL and TTR are pointers to types that are equivalent, ignoring
1185 their qualifiers, except for named address spaces. If the pointers point to
1186 different named addresses, then we must determine if one address space is a
1187 subset of the other. */
1189 static int
1191 {
1197 addr_space_t as_common;
1200 /* Fail if pointers point to incompatible address spaces. */
1204 /* Do not lose qualifiers on element types of array types that are
1205 pointer targets by taking their TYPE_MAIN_VARIANT. */
1221 }
1222 \f
1223 /* Subroutines of `comptypes'. */
1225 /* Determine whether two trees derive from the same translation unit.
1226 If the CONTEXT chain ends in a null, that tree's context is still
1227 being parsed, so if two trees have context chains ending in null,
1228 they're in the same translation unit. */
1229 int
1231 {
1234 {
1242 }
1246 {
1254 }
1257 }
1259 /* Allocate the seen two types, assuming that they are compatible. */
1263 {
1271 /* The C standard says that two structures in different translation
1272 units are compatible with each other only if the types of their
1273 fields are compatible (among other things). We assume that they
1274 are compatible until proven otherwise when building the cache.
1275 An example where this can occur is:
1276 struct a
1277 {
1278 struct a *next;
1279 };
1280 If we are comparing this against a similar struct in another TU,
1281 and did not assume they were compatible, we end up with an infinite
1282 loop. */
1285 }
1287 /* Free the seen types until we get to TU_TIL. */
1289 static void
1291 {
1294 {
1299 }
1301 }
1303 /* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
1304 compatible. If the two types are not the same (which has been
1305 checked earlier), this can only happen when multiple translation
1306 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
1307 rules. ENUM_AND_INT_P and DIFFERENT_TYPES_P are as in
1308 comptypes_internal. */
1310 static int
1313 {
1317 /* We have to verify that the tags of the types are the same. This
1318 is harder than it looks because this may be a typedef, so we have
1319 to go look at the original type. It may even be a typedef of a
1320 typedef...
1321 In the case of compiler-created builtin structs the TYPE_DECL
1322 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
1333 /* C90 didn't have the requirement that the two tags be the same. */
1337 /* C90 didn't say what happened if one or both of the types were
1338 incomplete; we choose to follow C99 rules here, which is that they
1339 are compatible. */
1344 {
1349 }
1352 {
1354 {
1356 /* Speed up the case where the type values are in the same order. */
1361 {
1363 }
1366 {
1370 {
1373 }
1374 }
1377 {
1379 }
1381 {
1384 }
1387 {
1390 }
1393 {
1397 {
1400 }
1401 }
1403 }
1406 {
1409 {
1412 }
1414 /* Speed up the common case where the fields are in the same order. */
1417 {
1428 {
1431 }
1438 {
1441 }
1442 }
1444 {
1447 }
1450 {
1455 {
1459 enum_and_int_p,
1460 different_types_p);
1465 {
1468 }
1479 }
1481 {
1484 }
1485 }
1488 }
1491 {
1497 {
1513 }
1516 else
1519 }
1523 }
1524 }
1526 /* Return 1 if two function types F1 and F2 are compatible.
1527 If either type specifies no argument types,
1528 the other must specify a fixed number of self-promoting arg types.
1529 Otherwise, if one type specifies only the number of arguments,
1530 the other must specify that number of self-promoting arg types.
1531 Otherwise, the argument types must match.
1532 ENUM_AND_INT_P and DIFFERENT_TYPES_P are as in comptypes_internal. */
1534 static int
1537 {
1539 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1547 /* 'volatile' qualifiers on a function's return type used to mean
1548 the function is noreturn. */
1568 /* An unspecified parmlist matches any specified parmlist
1569 whose argument types don't need default promotions. */
1572 {
1575 /* If one of these types comes from a non-prototype fn definition,
1576 compare that with the other type's arglist.
1577 If they don't match, ask for a warning (but no error). */
1583 }
1585 {
1593 }
1595 /* Both types have argument lists: compare them and propagate results. */
1597 different_types_p);
1599 }
1601 /* Check two lists of types for compatibility, returning 0 for
1602 incompatible, 1 for compatible, or 2 for compatible with
1603 warning. ENUM_AND_INT_P and DIFFERENT_TYPES_P are as in
1604 comptypes_internal. */
1606 static int
1609 {
1610 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1615 {
1619 /* If one list is shorter than the other,
1620 they fail to match. */
1629 /* A null pointer instead of a type
1630 means there is supposed to be an argument
1631 but nothing is specified about what type it has.
1632 So match anything that self-promotes. */
1637 {
1640 }
1642 {
1645 }
1646 /* If one of the lists has an error marker, ignore this arg. */
1649 ;
1651 different_types_p)))
1652 {
1655 /* Allow wait (union {union wait *u; int *i} *)
1656 and wait (union wait *) to be compatible. */
1663 {
1664 tree memb;
1667 {
1673 different_types_p))
1675 }
1678 }
1685 {
1686 tree memb;
1689 {
1695 different_types_p))
1697 }
1700 }
1701 else
1703 }
1705 /* comptypes said ok, but record if it said to warn. */
1711 }
1712 }
1713 \f
1714 /* Compute the size to increment a pointer by. */
1716 static tree
1718 {
1725 {
1728 }
1730 /* Convert in case a char is more than one unit. */
1734 }
1735 \f
1736 /* Return either DECL or its known constant value (if it has one). */
1738 tree
1740 {
1742 in a place where a variable is invalid. Note that DECL_INITIAL
1743 isn't valid for a PARM_DECL. */
1750 /* This is invalid if initial value is not constant.
1751 If it has either a function call, a memory reference,
1752 or a variable, then re-evaluating it could give different results. */
1754 /* Check for cases where this is sub-optimal, even though valid. */
1758 }
1760 /* Convert the array expression EXP to a pointer. */
1761 static tree
1763 {
1766 tree adr;
1768 tree ptrtype;
1782 /* In C++ array compound literals are temporary objects unless they are
1783 const or appear in namespace scope, so they are destroyed too soon
1784 to use them for much of anything (c++/53220). */
1786 {
1790 "converting an array compound literal to a pointer "
1792 }
1796 }
1798 /* Convert the function expression EXP to a pointer. */
1799 static tree
1801 {
1812 }
1814 /* Mark EXP as read, not just set, for set but not used -Wunused
1815 warning purposes. */
1817 void
1819 {
1821 {
1831 CASE_CONVERT:
1841 }
1842 }
1844 /* Perform the default conversion of arrays and functions to pointers.
1845 Return the result of converting EXP. For any other expression, just
1846 return EXP.
1848 LOC is the location of the expression. */
1850 struct c_expr
1852 {
1858 {
1860 {
1867 {
1871 }
1878 {
1879 /* Before C99, non-lvalue arrays do not decay to pointers.
1880 Normally, using such an array would be invalid; but it can
1881 be used correctly inside sizeof or as a statement expression.
1882 Thus, do not give an error here; an error will result later. */
1884 }
1887 }
1894 }
1897 }
1899 struct c_expr
1901 {
1904 }
1906 /* EXP is an expression of integer type. Apply the integer promotions
1907 to it and return the promoted value. */
1909 tree
1911 {
1917 /* Normally convert enums to int,
1918 but convert wide enums to something wider. */
1920 {
1928 }
1930 /* ??? This should no longer be needed now bit-fields have their
1931 proper types. */
1934 /* If it's thinner than an int, promote it like a
1935 c_promoting_integer_type_p, otherwise leave it alone. */
1941 {
1942 /* Preserve unsignedness if not really getting any wider. */
1948 }
1951 }
1954 /* Perform default promotions for C data used in expressions.
1955 Enumeral types or short or char are converted to int.
1956 In addition, manifest constants symbols are replaced by their values. */
1958 tree
1960 {
1961 tree orig_exp;
1964 tree promoted_type;
1968 /* Functions and arrays have been converted during parsing. */
1973 /* Constants can be used directly unless they're not loadable. */
1977 /* Strip no-op conversions. */
1985 {
1988 }
2002 }
2003 \f
2004 /* Look up COMPONENT in a structure or union TYPE.
2006 If the component name is not found, returns NULL_TREE. Otherwise,
2007 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
2008 stepping down the chain to the component, which is in the last
2009 TREE_VALUE of the list. Normally the list is of length one, but if
2010 the component is embedded within (nested) anonymous structures or
2011 unions, the list steps down the chain to the component. */
2013 static tree
2015 {
2016 tree field;
2018 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
2019 to the field elements. Use a binary search on this array to quickly
2020 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
2021 will always be set for structures which have many elements. */
2024 {
2032 {
2037 {
2038 /* Step through all anon unions in linear fashion. */
2040 {
2044 {
2050 /* The Plan 9 compiler permits referring
2051 directly to an anonymous struct/union field
2052 using a typedef name. */
2060 }
2061 }
2063 /* Entire record is only anon unions. */
2067 /* Restart the binary search, with new lower bound. */
2069 }
2075 else
2077 }
2083 }
2084 else
2085 {
2087 {
2091 {
2097 /* The Plan 9 compiler permits referring directly to an
2098 anonymous struct/union field using a typedef
2099 name. */
2106 }
2110 }
2114 }
2117 }
2119 /* Make an expression to refer to the COMPONENT field of structure or
2120 union value DATUM. COMPONENT is an IDENTIFIER_NODE. LOC is the
2121 location of the COMPONENT_REF. */
2123 tree
2125 {
2129 tree ref;
2135 /* Detect Objective-C property syntax object.property. */
2140 /* See if there is a field or component with name COMPONENT. */
2143 {
2145 {
2148 }
2153 {
2156 }
2158 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
2159 This might be better solved in future the way the C++ front
2160 end does it - by giving the anonymous entities each a
2161 separate name and type, and then have build_component_ref
2162 recursively call itself. We can't do that here. */
2163 do
2164 {
2167 tree subtype;
2173 /* If this is an rvalue, it does not have qualifiers in C
2174 standard terms and we must avoid propagating such
2175 qualifiers down to a non-lvalue array that is then
2176 converted to a pointer. */
2177 use_datum_quals = (datum_lvalue
2186 NULL_TREE);
2201 }
2205 }
2209 component);
2212 }
2213 \f
2214 /* Given an expression PTR for a pointer, return an expression
2215 for the value pointed to.
2216 ERRORSTRING is the name of the operator to appear in error messages.
2218 LOC is the location to use for the generated tree. */
2220 tree
2222 {
2225 tree ref;
2228 {
2231 {
2232 /* If a warning is issued, mark it to avoid duplicates from
2233 the backend. This only needs to be done at
2234 warn_strict_aliasing > 2. */
2239 }
2244 {
2248 }
2249 else
2250 {
2256 {
2259 }
2263 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2264 so that we get the proper error message if the result is used
2265 to assign to. Also, &* is supposed to be a no-op.
2266 And ANSI C seems to specify that the type of the result
2267 should be the const type. */
2268 /* A de-reference of a pointer to const is not a const. It is valid
2269 to change it via some other pointer. */
2276 }
2277 }
2282 }
2284 /* This handles expressions of the form "a[i]", which denotes
2285 an array reference.
2287 This is logically equivalent in C to *(a+i), but we may do it differently.
2288 If A is a variable or a member, we generate a primitive ARRAY_REF.
2289 This avoids forcing the array out of registers, and can work on
2290 arrays that are not lvalues (for example, members of structures returned
2291 by functions).
2293 For vector types, allow vector[i] but not i[vector], and create
2294 *(((type*)&vectortype) + i) for the expression.
2296 LOC is the location to use for the returned expression. */
2298 tree
2300 {
2301 tree ret;
2309 /* Allow vector[index] but not index[vector]. */
2311 {
2312 tree temp;
2315 {
2320 }
2325 }
2328 {
2331 }
2334 {
2337 }
2339 /* ??? Existing practice has been to warn only when the char
2340 index is syntactically the index, not for char[array]. */
2344 /* Apply default promotions *after* noticing character types. */
2352 {
2355 /* An array that is indexed by a non-constant
2356 cannot be stored in a register; we must be able to do
2357 address arithmetic on its address.
2358 Likewise an array of elements of variable size. */
2362 {
2365 }
2366 /* An array that is indexed by a constant value which is not within
2367 the array bounds cannot be stored in a register either; because we
2368 would get a crash in store_bit_field/extract_bit_field when trying
2369 to access a non-existent part of the register. */
2373 {
2376 }
2379 {
2389 }
2393 /* Array ref is const/volatile if the array elements are
2394 or if the array is. */
2403 /* This was added by rms on 16 Nov 91.
2404 It fixes vol struct foo *a; a->elts[1]
2405 in an inline function.
2406 Hope it doesn't break something else. */
2411 }
2412 else
2413 {
2422 return build_indirect_ref
2424 RO_ARRAY_INDEXING);
2425 }
2426 }
2427 \f
2428 /* Build an external reference to identifier ID. FUN indicates
2429 whether this will be used for a function call. LOC is the source
2430 location of the identifier. This sets *TYPE to the type of the
2431 identifier, which is not the same as the type of the returned value
2432 for CONST_DECLs defined as enum constants. If the type of the
2433 identifier is not available, *TYPE is set to NULL. */
2434 tree
2436 {
2437 tree ref;
2440 /* In Objective-C, an instance variable (ivar) may be preferred to
2441 whatever lookup_name() found. */
2446 {
2449 }
2451 /* Implicit function declaration. */
2454 /* Don't complain about something that's already been
2455 complained about. */
2457 else
2458 {
2461 }
2469 /* Recursive call does not count as usage. */
2471 {
2473 }
2476 {
2483 }
2486 {
2492 {
2497 }
2501 }
2507 {
2512 }
2513 /* C99 6.7.4p3: An inline definition of a function with external
2514 linkage ... shall not contain a reference to an identifier with
2515 internal linkage. */
2524 csi_internal);
2527 }
2529 /* Record details of decls possibly used inside sizeof or typeof. */
2530 struct maybe_used_decl
2531 {
2532 /* The decl. */
2533 tree decl;
2534 /* The level seen at (in_sizeof + in_typeof). */
2536 /* The next one at this level or above, or NULL. */
2538 };
2542 /* Record that DECL, an undefined static function reference seen
2543 inside sizeof or typeof, might be used if the operand of sizeof is
2544 a VLA type or the operand of typeof is a variably modified
2545 type. */
2547 static void
2549 {
2555 }
2557 /* Pop the stack of decls possibly used inside sizeof or typeof. If
2558 USED is false, just discard them. If it is true, mark them used
2559 (if no longer inside sizeof or typeof) or move them to the next
2560 level up (if still inside sizeof or typeof). */
2562 void
2564 {
2568 {
2570 {
2573 else
2575 }
2577 }
2580 }
2582 /* Return the result of sizeof applied to EXPR. */
2584 struct c_expr
2586 {
2589 {
2594 }
2595 else
2596 {
2605 {
2606 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */
2611 }
2613 }
2615 }
2617 /* Return the result of sizeof applied to T, a structure for the type
2618 name passed to sizeof (rather than the type itself). LOC is the
2619 location of the original expression. */
2621 struct c_expr
2623 {
2624 tree type;
2635 {
2636 /* If the type is a [*] array, it is a VLA but is represented as
2637 having a size of zero. In such a case we must ensure that
2638 the result of sizeof does not get folded to a constant by
2639 c_fully_fold, because if the size is evaluated the result is
2640 not constant and so constraints on zero or negative size
2641 arrays must not be applied when this sizeof call is inside
2642 another array declarator. */
2648 }
2652 }
2654 /* Build a function call to function FUNCTION with parameters PARAMS.
2655 The function call is at LOC.
2656 PARAMS is a list--a chain of TREE_LIST nodes--in which the
2657 TREE_VALUE of each node is a parameter-expression.
2658 FUNCTION's data type may be a function type or a pointer-to-function. */
2660 tree
2662 {
2664 tree ret;
2672 }
2674 /* Give a note about the location of the declaration of DECL. */
2677 {
2680 }
2682 /* Build a function call to function FUNCTION with parameters PARAMS.
2683 ORIGTYPES, if not NULL, is a vector of types; each element is
2684 either NULL or the original type of the corresponding element in
2685 PARAMS. The original type may differ from TREE_TYPE of the
2686 parameter for enums. FUNCTION's data type may be a function type
2687 or pointer-to-function. This function changes the elements of
2688 PARAMS. */
2690 tree
2694 {
2697 tree tem;
2702 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2705 /* Convert anything with function type to a pointer-to-function. */
2707 {
2708 /* Implement type-directed function overloading for builtins.
2709 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
2710 handle all the type checking. The result is a complete expression
2711 that implements this function call. */
2721 /* Atomic functions have type checking/casting already done. They are
2722 often rewritten and don't match the original parameter list. */
2725 }
2729 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2730 expressions, like those used for ObjC messenger dispatches. */
2743 {
2747 function);
2749 {
2752 function);
2754 }
2755 else
2759 }
2764 /* fntype now gets the type of function pointed to. */
2767 /* Convert the parameters to the types declared in the
2768 function prototype, or apply default promotions. */
2775 /* Check that the function is called through a compatible prototype.
2776 If it is not, replace the call by a trap, wrapped up in a compound
2777 expression if necessary. This has the nice side-effect to prevent
2778 the tree-inliner from generating invalid assignment trees which may
2779 blow up in the RTL expander later. */
2784 {
2788 NULL_TREE);
2791 /* This situation leads to run-time undefined behavior. We can't,
2792 therefore, simply error unless we can prove that all possible
2793 executions of the program must execute the code. */
2795 /* We can, however, treat "undefined" any way we please.
2796 Call abort to encourage the user to fix the program. */
2798 /* Before the abort, allow the function arguments to exit or
2799 call longjmp. */
2804 {
2809 }
2810 else
2811 {
2812 tree rhs;
2817 NULL),
2819 else
2824 }
2825 }
2829 /* Check that arguments to builtin functions match the expectations. */
2836 /* Check that the arguments to the function are valid. */
2841 {
2843 result =
2846 else
2852 }
2853 else
2858 {
2863 }
2865 }
2866 \f
2867 /* Convert the argument expressions in the vector VALUES
2868 to the types in the list TYPELIST.
2870 If TYPELIST is exhausted, or when an element has NULL as its type,
2871 perform the default conversions.
2873 ORIGTYPES is the original types of the expressions in VALUES. This
2874 holds the type of enum values which have been converted to integral
2875 types. It may be NULL.
2877 FUNCTION is a tree for the called function. It is used only for
2878 error messages, where it is formatted with %qE.
2880 This is also where warnings about wrong number of args are generated.
2882 Returns the actual number of arguments processed (which may be less
2883 than the length of VALUES in some error situations), or -1 on
2884 failure. */
2886 static int
2889 {
2896 tree selector;
2898 /* Change pointer to function to the function itself for
2899 diagnostics. */
2904 /* Handle an ObjC selector specially for diagnostics. */
2907 /* For type-generic built-in functions, determine whether excess
2908 precision should be removed (classification) or not
2909 (comparison). */
2913 {
2915 {
2928 }
2929 }
2931 /* Scan the given expressions and types, producing individual
2932 converted arguments. */
2937 {
2945 tree parmval;
2948 {
2952 else
2957 }
2960 {
2963 }
2967 /* If there is excess precision and a prototype, convert once to
2968 the required type rather than converting via the semantic
2969 type. Likewise without a prototype a float value represented
2970 as long double should be converted once to double. But for
2971 type-generic classification functions excess precision must
2972 be removed here. */
2975 {
2978 }
2985 {
2986 /* Formal parm type is specified by a function prototype. */
2989 {
2992 }
2993 else
2994 {
2995 tree origtype;
2997 /* Optionally warn about conversions that
2998 differ from the default conversions. */
3000 {
3033 /* ??? At some point, messages should be written about
3034 conversions between complex types, but that's too messy
3035 to do now. */
3038 {
3039 /* Warn if any argument is passed as `float',
3040 since without a prototype it would be `double'. */
3047 /* Warn if mismatch between argument and prototype
3048 for decimal float types. Warn of conversions with
3049 binary float types and of precision narrowing due to
3050 prototype. */
3058 && (formal_prec
3061 && (valtype
3062 != dfloat64_type_node
3063 && (valtype
3066 && (valtype
3072 }
3073 /* Detect integer changing in width or signedness.
3074 These warnings are only activated with
3075 -Wtraditional-conversion, not with -Wtraditional. */
3078 {
3085 /* No warning if function asks for enum
3086 and the actual arg is that enum type. */
3087 ;
3090 "passing argument %d of %qE "
3094 ;
3095 /* Don't complain if the formal parameter type
3096 is an enum, because we can't tell now whether
3097 the value was an enum--even the same enum. */
3099 ;
3102 /* Change in signedness doesn't matter
3103 if a constant value is unaffected. */
3104 ;
3105 /* If the value is extended from a narrower
3106 unsigned type, it doesn't matter whether we
3107 pass it as signed or unsigned; the value
3108 certainly is the same either way. */
3111 ;
3114 "passing argument %d of %qE "
3117 else
3119 "passing argument %d of %qE "
3121 }
3122 }
3124 /* Possibly restore an EXCESS_PRECISION_EXPR for the
3125 sake of better warnings from convert_and_check. */
3138 }
3139 }
3144 {
3147 else
3148 {
3149 /* Convert `float' to `double'. */
3152 "implicit conversion from %qT to %qT when passing "
3156 }
3157 }
3159 /* A "double" argument with excess precision being passed
3160 without a prototype or in variable arguments. */
3164 {
3167 }
3168 else
3169 /* Convert `short' and `char' to full-size `int'. */
3178 }
3183 {
3188 }
3191 }
3192 \f
3193 /* This is the entry point used by the parser to build unary operators
3194 in the input. CODE, a tree_code, specifies the unary operator, and
3195 ARG is the operand. For unary plus, the C parser currently uses
3196 CONVERT_EXPR for code.
3198 LOC is the location to use for the tree generated.
3199 */
3201 struct c_expr
3203 {
3214 }
3216 /* This is the entry point used by the parser to build binary operators
3217 in the input. CODE, a tree_code, specifies the binary operator, and
3218 ARG1 and ARG2 are the operands. In addition to constructing the
3219 expression, we check for operands that were written with other binary
3220 operators in a way that is likely to confuse the user.
3222 LOCATION is the location of the binary operator. */
3224 struct c_expr
3227 {
3250 /* Check for cases such as x+y<<z which users are likely
3251 to misinterpret. */
3260 /* Warn about comparisons against string literals, with the exception
3261 of testing for equality or inequality of a string literal with NULL. */
3263 {
3268 }
3279 /* Warn about comparisons of different enum types. */
3290 }
3291 \f
3292 /* Return a tree for the difference of pointers OP0 and OP1.
3293 The resulting tree has type int. */
3295 static tree
3297 {
3307 /* If the operands point into different address spaces, we need to
3308 explicitly convert them to pointers into the common address space
3309 before we can subtract the numerical address values. */
3311 {
3312 addr_space_t as_common;
3313 tree common_type;
3315 /* Determine the common superset address space. This is guaranteed
3316 to exist because the caller verified that comp_target_types
3317 returned non-zero. */
3324 }
3326 /* Determine integer type to perform computations in. This will usually
3327 be the same as the result type (ptrdiff_t), but may need to be a wider
3328 type if pointers for the address space are wider than ptrdiff_t. */
3331 else
3342 /* If the conversion to ptrdiff_type does anything like widening or
3343 converting a partial to an integral mode, we get a convert_expression
3344 that is in the way to do any simplifications.
3345 (fold-const.c doesn't know that the extra bits won't be needed.
3346 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
3347 different mode in place.)
3348 So first try to find a common term here 'by hand'; we want to cover
3349 at least the cases that occur in legal static initializers. */
3354 else
3360 else
3364 {
3367 }
3368 else
3372 {
3375 }
3376 else
3380 {
3383 }
3386 /* First do the subtraction as integers;
3387 then drop through to build the divide operator.
3388 Do not do default conversions on the minus operator
3389 in case restype is a short type. */
3394 /* This generates an error if op1 is pointer to incomplete type. */
3398 /* This generates an error if op0 is pointer to incomplete type. */
3401 /* Divide by the size, in easiest possible way. */
3405 /* Convert to final result type if necessary. */
3407 }
3408 \f
3409 /* Construct and perhaps optimize a tree representation
3410 for a unary operation. CODE, a tree_code, specifies the operation
3411 and XARG is the operand.
3412 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
3413 the default promotions (such as from short to int).
3414 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
3415 allows non-lvalues; this is only used to handle conversion of non-lvalue
3416 arrays to pointers in C99.
3418 LOCATION is the location of the operator. */
3420 tree
3423 {
3424 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3428 tree val;
3450 {
3453 }
3456 {
3459 }
3462 {
3464 /* This is used for unary plus, because a CONVERT_EXPR
3465 is enough to prevent anybody from looking inside for
3466 associativity, but won't generate any code. */
3470 {
3473 }
3483 {
3486 }
3492 /* ~ works on integer types and non float vectors. */
3496 {
3499 }
3501 {
3507 }
3508 else
3509 {
3512 }
3517 {
3520 }
3526 /* Conjugating a real value is a no-op, but allow it anyway. */
3529 {
3532 }
3541 {
3545 }
3547 {
3550 }
3551 else
3554 /* If the TRUTH_NOT_EXPR has been folded, reset the location. */
3574 {
3584 }
3586 /* Complain about anything that is not a true lvalue. In
3587 Objective-C, skip this check for property_refs. */
3592 ? lv_increment
3597 {
3601 else
3604 }
3606 /* Ensure the argument is fully folded inside any SAVE_EXPR. */
3609 /* Increment or decrement the real part of the value,
3610 and don't change the imaginary part. */
3612 {
3627 }
3629 /* Report invalid types. */
3633 {
3636 else
3640 }
3642 {
3643 tree inc;
3647 /* Compute the increment. */
3650 {
3651 /* If pointer target is an undefined struct,
3652 we just cannot know how to do the arithmetic. */
3654 {
3658 else
3661 }
3664 {
3668 else
3671 }
3675 }
3677 {
3678 /* For signed fract types, we invert ++ to -- or
3679 -- to ++, and change inc from 1 to -1, because
3680 it is not possible to represent 1 in signed fract constants.
3681 For unsigned fract types, the result always overflows and
3682 we get an undefined (original) or the maximum value. */
3694 }
3695 else
3696 {
3699 }
3701 /* If 'arg' is an Objective-C PROPERTY_REF expression, then we
3702 need to ask Objective-C to build the increment or decrement
3703 expression for it. */
3708 /* Report a read-only lvalue. */
3710 {
3716 }
3725 else
3732 }
3735 /* Note that this operation never does default_conversion. */
3737 /* The operand of unary '&' must be an lvalue (which excludes
3738 expressions of type void), or, in C99, the result of a [] or
3739 unary '*' operator. */
3746 /* Let &* cancel out to simplify resulting code. */
3748 {
3749 /* Don't let this be an lvalue. */
3754 }
3756 /* For &x[y], return x+y */
3758 {
3762 }
3764 /* Anything not already handled and not a true memory reference
3765 or a non-lvalue array is an error. */
3770 /* Move address operations inside C_MAYBE_CONST_EXPR to simplify
3771 folding later. */
3773 {
3782 }
3784 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3787 /* If the lvalue is const or volatile, merge that into the type
3788 to which the address will point. This is only needed
3789 for function types. */
3793 {
3803 }
3813 /* ??? Cope with user tricks that amount to offsetof. Delete this
3814 when we have proper support for integer constant expressions. */
3818 {
3821 }
3830 }
3835 ret = (require_constant_value
3838 else
3840 return_build_unary_op:
3851 }
3853 /* Return nonzero if REF is an lvalue valid for this language.
3854 Lvalues can be assigned, unless their type has TYPE_READONLY.
3855 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
3857 bool
3859 {
3863 {
3890 }
3891 }
3892 \f
3893 /* Give a warning for storing in something that is read-only in GCC
3894 terms but not const in ISO C terms. */
3896 static void
3898 {
3900 {
3912 }
3914 }
3917 /* Return nonzero if REF is an lvalue valid for this language;
3918 otherwise, print an error message and return zero. USE says
3919 how the lvalue is being used and so selects the error message.
3920 LOCATION is the location at which any error should be reported. */
3922 static int
3924 {
3931 }
3932 \f
3933 /* Mark EXP saying that we need to be able to take the
3934 address of it; it should not be allocated in a register.
3935 Returns true if successful. */
3937 bool
3939 {
3944 {
3947 {
3948 error
3951 }
3953 /* ... fall through ... */
3973 {
3975 {
3976 error
3979 }
3981 }
3983 {
3986 else
3989 }
3991 /* drops in */
3994 /* drops out */
3997 }
3998 }
3999 \f
4000 /* Convert EXPR to TYPE, warning about conversion problems with
4001 constants. SEMANTIC_TYPE is the type this conversion would use
4002 without excess precision. If SEMANTIC_TYPE is NULL, this function
4003 is equivalent to convert_and_check. This function is a wrapper that
4004 handles conversions that may be different than
4005 the usual ones because of excess precision. */
4007 static tree
4009 {
4018 {
4019 /* For integers, we need to check the real conversion, not
4020 the conversion to the excess precision type. */
4022 }
4023 /* Result type is the excess precision type, which should be
4024 large enough, so do not check. */
4026 }
4028 /* Build and return a conditional expression IFEXP ? OP1 : OP2. If
4029 IFEXP_BCP then the condition is a call to __builtin_constant_p, and
4030 if folded to an integer constant then the unselected half may
4031 contain arbitrary operations not normally permitted in constant
4032 expressions. Set the location of the expression to LOC. */
4034 tree
4037 tree op2_original_type)
4038 {
4039 tree type1;
4040 tree type2;
4048 tree ret;
4060 /* Promote both alternatives. */
4077 /* C90 does not permit non-lvalue arrays in conditional expressions.
4078 In C99 they will be pointers by now. */
4080 {
4083 }
4091 {
4094 {
4098 }
4100 {
4104 }
4105 }
4108 {
4119 }
4121 /* Quickly detect the usual case where op1 and op2 have the same type
4122 after promotion. */
4124 {
4127 else
4129 }
4134 {
4137 "implicit conversion from %qT to %qT to "
4139 colon_loc);
4141 /* If -Wsign-compare, warn here if type1 and type2 have
4142 different signedness. We'll promote the signed to unsigned
4143 and later code won't know it used to be different.
4144 Do this check on the original types, so that explicit casts
4145 will be considered, but default promotions won't. */
4147 {
4152 {
4155 /* Do not warn if the result type is signed, since the
4156 signed type will only be chosen if it can represent
4157 all the values of the unsigned type. */
4160 else
4161 {
4165 /* Do not warn if the signed quantity is an
4166 unsuffixed integer literal (or some static
4167 constant expression involving such literals) and
4168 it is non-negative. This warning requires the
4169 operands to be folded for best results, so do
4170 that folding in this case even without
4171 warn_sign_compare to avoid warning options
4172 possibly affecting code generation. */
4173 c_inhibit_evaluation_warnings
4177 c_inhibit_evaluation_warnings
4180 c_inhibit_evaluation_warnings
4184 c_inhibit_evaluation_warnings
4188 {
4191 || (unsigned_op1
4194 else
4198 }
4203 }
4204 }
4205 }
4206 }
4208 {
4213 }
4215 {
4218 addr_space_t as_common;
4227 {
4231 }
4233 {
4236 "ISO C forbids conditional expr between "
4240 }
4242 {
4245 "ISO C forbids conditional expr between "
4249 }
4250 /* Objective-C pointer comparisons are a bit more lenient. */
4253 else
4254 {
4259 result_type = build_pointer_type
4261 }
4262 }
4264 {
4268 else
4269 {
4271 }
4273 }
4275 {
4279 else
4280 {
4282 }
4284 }
4287 {
4290 else
4291 {
4294 }
4295 }
4297 /* Merge const and volatile flags of the incoming types. */
4298 result_type
4307 {
4310 }
4312 {
4315 }
4317 && op1_int_operands
4320 {
4327 }
4330 else
4331 {
4333 {
4336 }
4340 }
4346 }
4347 \f
4348 /* Return a compound expression that performs two expressions and
4349 returns the value of the second of them.
4351 LOC is the location of the COMPOUND_EXPR. */
4353 tree
4355 {
4358 tree ret;
4370 {
4373 }
4376 {
4377 /* The left-hand operand of a comma expression is like an expression
4378 statement: with -Wunused, we should warn if it doesn't have
4379 any side-effects, unless it was explicitly cast to (void). */
4381 {
4389 else
4392 }
4393 }
4395 /* With -Wunused, we should also warn if the left-hand operand does have
4396 side-effects, but computes a value which is not used. For example, in
4397 `foo() + bar(), baz()' the result of the `+' operator is not used,
4398 so we should issue a warning. */
4408 && expr1_int_operands
4417 }
4419 /* Issue -Wcast-qual warnings when appropriate. TYPE is the type to
4420 which we are casting. OTYPE is the type of the expression being
4421 cast. Both TYPE and OTYPE are pointer types. LOC is the location
4422 of the cast. -Wcast-qual appeared on the command line. Named
4423 address space qualifiers are not handled here, because they result
4424 in different warnings. */
4426 static void
4428 {
4435 /* Check that the qualifiers on IN_TYPE are a superset of the
4436 qualifiers of IN_OTYPE. The outermost level of POINTER_TYPE
4437 nodes is uninteresting and we stop as soon as we hit a
4438 non-POINTER_TYPE node on either type. */
4439 do
4440 {
4444 /* GNU C allows cv-qualified function types. 'const' means the
4445 function is very pure, 'volatile' means it can't return. We
4446 need to warn when such qualifiers are added, not when they're
4447 taken away. */
4452 else
4455 }
4464 /* There are qualifiers present in IN_OTYPE that are not present
4465 in IN_TYPE. */
4468 discarded);
4473 /* A cast from **T to const **T is unsafe, because it can cause a
4474 const value to be changed with no additional warning. We only
4475 issue this warning if T is the same on both sides, and we only
4476 issue the warning if there are the same number of pointers on
4477 both sides, as otherwise the cast is clearly unsafe anyhow. A
4478 cast is unsafe when a qualifier is added at one level and const
4479 is not present at all outer levels.
4481 To issue this warning, we check at each level whether the cast
4482 adds new qualifiers not already seen. We don't need to special
4483 case function types, as they won't have the same
4484 TYPE_MAIN_VARIANT. */
4494 do
4495 {
4500 {
4502 "to be safe all intermediate pointers in cast from "
4506 }
4509 }
4511 }
4513 /* Build an expression representing a cast to type TYPE of expression EXPR.
4514 LOC is the location of the cast-- typically the open paren of the cast. */
4516 tree
4518 {
4519 tree value;
4529 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
4530 only in <protocol> qualifications. But when constructing cast expressions,
4531 the protocols do matter and must be kept around. */
4538 {
4541 }
4544 {
4547 }
4550 {
4554 }
4557 {
4562 }
4564 {
4565 tree field;
4574 {
4575 tree t;
4587 }
4590 }
4591 else
4592 {
4596 {
4600 }
4604 /* Optionally warn about potentially worrisome casts. */
4610 /* Warn about conversions between pointers to disjoint
4611 address spaces. */
4615 {
4618 addr_space_t as_common;
4621 {
4632 else
4637 }
4638 }
4640 /* Warn about possible alignment problems. */
4646 /* Don't warn about opaque types, where the actual alignment
4647 restriction is unknown. */
4658 /* Unlike conversion of integers to pointers, where the
4659 warning is disabled for converting constants because
4660 of cases such as SIG_*, warn about converting constant
4661 pointers to integers. In some cases it may cause unwanted
4662 sign extension, and a warning is appropriate. */
4669 "cast from function call of type %qT "
4675 /* Don't warn about converting any constant. */
4684 /* If pedantic, warn for conversions between function and object
4685 pointer types, except for converting a null pointer constant
4686 to function pointer type. */
4707 /* Ignore any integer overflow caused by the cast. */
4709 {
4711 {
4713 {
4714 /* Avoid clobbering a shared constant. */
4717 }
4718 }
4720 /* Reset VALUE's overflow flags, ensuring constant sharing. */
4724 }
4725 }
4727 /* Don't let a cast be an lvalue. */
4731 /* Don't allow the results of casting to floating-point or complex
4732 types be confused with actual constants, or casts involving
4733 integer and pointer types other than direct integer-to-integer
4734 and integer-to-pointer be confused with integer constant
4735 expressions and null pointer constants. */
4748 }
4750 /* Interpret a cast of expression EXPR to type TYPE. LOC is the
4751 location of the open paren of the cast, or the position of the cast
4752 expr. */
4753 tree
4755 {
4756 tree type;
4759 tree ret;
4762 /* This avoids warnings about unprototyped casts on
4763 integers. E.g. "#define SIG_DFL (void(*)())0". */
4771 {
4778 }
4783 /* C++ does not permits types to be defined in a cast, but it
4784 allows references to incomplete types. */
4790 }
4791 \f
4792 /* Build an assignment expression of lvalue LHS from value RHS.
4793 If LHS_ORIGTYPE is not NULL, it is the original type of LHS, which
4794 may differ from TREE_TYPE (LHS) for an enum bitfield.
4795 MODIFYCODE is the code for a binary operator that we use
4796 to combine the old value of LHS with RHS to get the new value.
4797 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
4798 If RHS_ORIGTYPE is not NULL_TREE, it is the original type of RHS,
4799 which may differ from TREE_TYPE (RHS) for an enum value.
4801 LOCATION is the location of the MODIFYCODE operator.
4802 RHS_LOC is the location of the RHS. */
4804 tree
4808 {
4809 tree result;
4810 tree newrhs;
4816 /* Types that aren't fully specified cannot be used in assignments. */
4819 /* Avoid duplicate error messages from operands that had errors. */
4823 /* For ObjC properties, defer this check. */
4828 {
4831 }
4836 {
4839 rhs_origtype);
4848 }
4850 /* If a binary op has been requested, combine the old LHS value with the RHS
4851 producing the value we should actually store into the LHS. */
4854 {
4860 /* The original type of the right hand side is no longer
4861 meaningful. */
4863 }
4866 {
4867 /* Check if we are modifying an Objective-C property reference;
4868 if so, we need to generate setter calls. */
4873 /* Else, do the check that we postponed for Objective-C. */
4876 }
4878 /* Give an error for storing in something that is 'const'. */
4884 {
4887 }
4891 /* If storing into a structure or union member,
4892 it has probably been given type `int'.
4893 Compute the type that would go with
4894 the actual amount of storage the member occupies. */
4903 /* If storing in a field that is in actuality a short or narrower than one,
4904 we must store in the field in its actual type. */
4907 {
4910 }
4912 /* Issue -Wc++-compat warnings about an assignment to an enum type
4913 when LHS does not have its original type. This happens for,
4914 e.g., an enum bitfield in a struct. */
4919 {
4921 ? rhs_origtype
4927 }
4929 /* Convert new value to destination type. Fold it first, then
4930 restore any excess precision information, for the sake of
4931 conversion warnings. */
4942 /* Emit ObjC write barrier, if necessary. */
4944 {
4947 {
4950 }
4951 }
4953 /* Scan operands. */
4959 /* If we got the LHS in a different type for storing in,
4960 convert the result back to the nominal type of LHS
4961 so that the value we return always has the same type
4962 as the LHS argument. */
4971 }
4972 \f
4973 /* Return whether STRUCT_TYPE has an anonymous field with type TYPE.
4974 This is used to implement -fplan9-extensions. */
4976 static bool
4978 {
4979 tree field;
4988 {
4991 {
4995 }
5000 {
5004 }
5005 }
5007 }
5009 /* RHS is an expression whose type is pointer to struct. If there is
5010 an anonymous field in RHS with type TYPE, then return a pointer to
5011 that field in RHS. This is used with -fplan9-extensions. This
5012 returns NULL if no conversion could be found. */
5014 static tree
5016 {
5020 tree ret;
5035 {
5041 {
5045 }
5047 lhs_main_type))
5048 {
5053 }
5054 }
5061 NULL_TREE);
5065 {
5068 }
5071 }
5073 /* Convert value RHS to type TYPE as preparation for an assignment to
5074 an lvalue of type TYPE. If ORIGTYPE is not NULL_TREE, it is the
5075 original type of RHS; this differs from TREE_TYPE (RHS) for enum
5076 types. NULL_POINTER_CONSTANT says whether RHS was a null pointer
5077 constant before any folding.
5078 The real work of conversion is done by `convert'.
5079 The purpose of this function is to generate error messages
5080 for assignments that are not allowed in C.
5081 ERRTYPE says whether it is argument passing, assignment,
5082 initialization or return.
5084 LOCATION is the location of the RHS.
5085 FUNCTION is a tree for the function being called.
5086 PARMNUM is the number of the argument, for printing in error messages. */
5088 static tree
5093 {
5096 tree rhstype;
5102 {
5103 tree selector;
5104 /* Change pointer to function to the function itself for
5105 diagnostics. */
5110 /* Handle an ObjC selector specially for diagnostics. */
5114 {
5117 }
5118 }
5120 /* This macro is used to emit diagnostics to ensure that all format
5121 strings are complete sentences, visible to gettext and checked at
5122 compile time. */
5123 #define WARN_FOR_ASSIGNMENT(LOCATION, OPT, AR, AS, IN, RE) \
5124 do { \
5125 switch (errtype) \
5126 { \
5127 case ic_argpass: \
5128 if (pedwarn (LOCATION, OPT, AR, parmnum, rname)) \
5129 inform ((fundecl && !DECL_IS_BUILTIN (fundecl)) \
5130 ? DECL_SOURCE_LOCATION (fundecl) : LOCATION, \
5132 type, rhstype); \
5133 break; \
5134 case ic_assign: \
5135 pedwarn (LOCATION, OPT, AS); \
5136 break; \
5137 case ic_init: \
5138 pedwarn_init (LOCATION, OPT, IN); \
5139 break; \
5140 case ic_return: \
5141 pedwarn (LOCATION, OPT, RE); \
5142 break; \
5143 default: \
5144 gcc_unreachable (); \
5145 } \
5146 } while (0)
5148 /* This macro is used to emit diagnostics to ensure that all format
5149 strings are complete sentences, visible to gettext and checked at
5150 compile time. It is the same as WARN_FOR_ASSIGNMENT but with an
5151 extra parameter to enumerate qualifiers. */
5153 #define WARN_FOR_QUALIFIERS(LOCATION, OPT, AR, AS, IN, RE, QUALS) \
5154 do { \
5155 switch (errtype) \
5156 { \
5157 case ic_argpass: \
5158 if (pedwarn (LOCATION, OPT, AR, parmnum, rname, QUALS)) \
5159 inform ((fundecl && !DECL_IS_BUILTIN (fundecl)) \
5160 ? DECL_SOURCE_LOCATION (fundecl) : LOCATION, \
5162 type, rhstype); \
5163 break; \
5164 case ic_assign: \
5165 pedwarn (LOCATION, OPT, AS, QUALS); \
5166 break; \
5167 case ic_init: \
5168 pedwarn (LOCATION, OPT, IN, QUALS); \
5169 break; \
5170 case ic_return: \
5171 pedwarn (LOCATION, OPT, RE, QUALS); \
5172 break; \
5173 default: \
5174 gcc_unreachable (); \
5175 } \
5176 } while (0)
5188 {
5192 {
5208 }
5211 }
5214 {
5219 {
5229 }
5230 }
5236 {
5237 /* Except for passing an argument to an unprototyped function,
5238 this is a constraint violation. When passing an argument to
5239 an unprototyped function, it is compile-time undefined;
5240 making it a constraint in that case was rejected in
5241 DR#252. */
5244 }
5248 /* A type converts to a reference to it.
5249 This code doesn't fully support references, it's just for the
5250 special case of va_start and va_copy. */
5253 {
5255 {
5258 }
5264 /* We already know that these two types are compatible, but they
5265 may not be exactly identical. In fact, `TREE_TYPE (type)' is
5266 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
5267 likely to be va_list, a typedef to __builtin_va_list, which
5268 is different enough that it will cause problems later. */
5270 {
5273 }
5278 }
5279 /* Some types can interconvert without explicit casts. */
5283 /* Arithmetic types all interconvert, and enum is treated like int. */
5292 {
5293 tree ret;
5301 }
5303 /* Aggregates in different TUs might need conversion. */
5309 /* Conversion to a transparent union or record from its member types.
5310 This applies only to function arguments. */
5314 {
5318 {
5329 {
5333 /* Any non-function converts to a [const][volatile] void *
5334 and vice versa; otherwise, targets must be the same.
5335 Meanwhile, the lhs target must have all the qualifiers of
5336 the rhs. */
5339 {
5340 /* If this type won't generate any warnings, use it. */
5350 /* Keep looking for a better type, but remember this one. */
5353 }
5354 }
5356 /* Can convert integer zero to any pointer type. */
5358 {
5361 }
5362 }
5365 {
5367 {
5368 /* We have only a marginally acceptable member type;
5369 it needs a warning. */
5373 /* Const and volatile mean something different for function
5374 types, so the usual warnings are not appropriate. */
5377 {
5378 /* Because const and volatile on functions are
5379 restrictions that say the function will not do
5380 certain things, it is okay to use a const or volatile
5381 function where an ordinary one is wanted, but not
5382 vice-versa. */
5387 "makes %q#v qualified function "
5390 "function pointer from "
5393 "function pointer from "
5398 }
5413 }
5421 }
5422 }
5424 /* Conversions among pointers */
5427 {
5434 addr_space_t asl;
5435 addr_space_t asr;
5441 /* Opaque pointers are treated like void pointers. */
5444 /* The Plan 9 compiler permits a pointer to a struct to be
5445 automatically converted into a pointer to an anonymous field
5446 within the struct. */
5451 {
5454 {
5460 }
5461 }
5463 /* C++ does not allow the implicit conversion void* -> T*. However,
5464 for the purpose of reducing the number of false positives, we
5465 tolerate the special case of
5467 int *p = NULL;
5469 where NULL is typically defined in C to be '(void *) 0'. */
5472 "request for implicit conversion "
5475 /* See if the pointers point to incompatible address spaces. */
5480 {
5482 {
5501 }
5503 }
5505 /* Check if the right-hand side has a format attribute but the
5506 left-hand side doesn't. */
5509 {
5511 {
5514 "argument %d of %qE might be "
5520 "assignment left-hand side might be "
5525 "initialization left-hand side might be "
5530 "return type might be "
5535 }
5536 }
5538 /* Any non-function converts to a [const][volatile] void *
5539 and vice versa; otherwise, targets must be the same.
5540 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
5543 || is_opaque_pointer
5548 {
5551 ||
5553 && !null_pointer_constant
5557 "%qE between function pointer "
5565 /* Const and volatile mean something different for function types,
5566 so the usual warnings are not appropriate. */
5569 {
5572 {
5583 }
5584 /* If this is not a case of ignoring a mismatch in signedness,
5585 no warning. */
5588 ;
5589 /* If there is a mismatch, do warn. */
5600 }
5603 {
5604 /* Because const and volatile on functions are restrictions
5605 that say the function will not do certain things,
5606 it is okay to use a const or volatile function
5607 where an ordinary one is wanted, but not vice-versa. */
5612 "%q#v qualified function pointer "
5621 }
5622 }
5623 else
5624 /* Avoid warning about the volatile ObjC EH puts on decls. */
5635 }
5637 {
5638 /* ??? This should not be an error when inlining calls to
5639 unprototyped functions. */
5642 }
5644 {
5645 /* An explicit constant 0 can convert to a pointer,
5646 or one that results from arithmetic, even including
5647 a cast to integer type. */
5660 }
5662 {
5673 }
5675 {
5676 tree ret;
5682 }
5685 {
5703 "incompatible types when returning type %qT but %qT was "
5708 }
5711 }
5712 \f
5713 /* If VALUE is a compound expr all of whose expressions are constant, then
5714 return its value. Otherwise, return error_mark_node.
5716 This is for handling COMPOUND_EXPRs as initializer elements
5717 which is allowed with a warning when -pedantic is specified. */
5719 static tree
5721 {
5723 {
5728 endtype);
5729 }
5732 else
5734 }
5735 \f
5736 /* Perform appropriate conversions on the initial value of a variable,
5737 store it in the declaration DECL,
5738 and print any error messages that are appropriate.
5739 If ORIGTYPE is not NULL_TREE, it is the original type of INIT.
5740 If the init is invalid, store an ERROR_MARK.
5742 INIT_LOC is the location of the initial value. */
5744 void
5746 {
5750 /* If variable's type was invalidly declared, just ignore it. */
5756 /* Digest the specified initializer into an expression. */
5763 /* Store the expression if valid; else report error. */
5772 /* ANSI wants warnings about out-of-range constant initializers. */
5777 /* Check if we need to set array size from compound literal size. */
5781 {
5788 {
5792 {
5793 /* For int foo[] = (int [3]){1}; we need to set array size
5794 now since later on array initializer will be just the
5795 brace enclosed list of the compound literal. */
5803 }
5804 }
5805 }
5806 }
5807 \f
5808 /* Methods for storing and printing names for error messages. */
5810 /* Implement a spelling stack that allows components of a name to be pushed
5811 and popped. Each element on the stack is this structure. */
5813 struct spelling
5814 {
5816 union
5817 {
5821 };
5823 #define SPELLING_STRING 1
5824 #define SPELLING_MEMBER 2
5825 #define SPELLING_BOUNDS 3
5831 /* Macros to save and restore the spelling stack around push_... functions.
5832 Alternative to SAVE_SPELLING_STACK. */
5834 #define SPELLING_DEPTH() (spelling - spelling_base)
5835 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
5837 /* Push an element on the spelling stack with type KIND and assign VALUE
5838 to MEMBER. */
5840 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
5841 { \
5842 int depth = SPELLING_DEPTH (); \
5843 \
5844 if (depth >= spelling_size) \
5845 { \
5846 spelling_size += 10; \
5847 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
5848 spelling_size); \
5849 RESTORE_SPELLING_DEPTH (depth); \
5850 } \
5851 \
5852 spelling->kind = (KIND); \
5853 spelling->MEMBER = (VALUE); \
5854 spelling++; \
5855 }
5857 /* Push STRING on the stack. Printed literally. */
5859 static void
5861 {
5863 }
5865 /* Push a member name on the stack. Printed as '.' STRING. */
5867 static void
5869 {
5875 }
5877 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
5879 static void
5881 {
5883 }
5885 /* Compute the maximum size in bytes of the printed spelling. */
5887 static int
5889 {
5894 {
5897 else
5899 }
5902 }
5904 /* Print the spelling to BUFFER and return it. */
5908 {
5914 {
5917 }
5918 else
5919 {
5924 ;
5925 }
5928 }
5930 /* Issue an error message for a bad initializer component.
5931 GMSGID identifies the message.
5932 The component name is taken from the spelling stack. */
5934 void
5936 {
5939 /* The gmsgid may be a format string with %< and %>. */
5944 }
5946 /* Issue a pedantic warning for a bad initializer component. OPT is
5947 the option OPT_* (from options.h) controlling this warning or 0 if
5948 it is unconditionally given. GMSGID identifies the message. The
5949 component name is taken from the spelling stack. */
5951 void
5953 {
5956 /* The gmsgid may be a format string with %< and %>. */
5961 }
5963 /* Issue a warning for a bad initializer component.
5965 OPT is the OPT_W* value corresponding to the warning option that
5966 controls this warning. GMSGID identifies the message. The
5967 component name is taken from the spelling stack. */
5969 static void
5971 {
5974 /* The gmsgid may be a format string with %< and %>. */
5979 }
5980 \f
5981 /* If TYPE is an array type and EXPR is a parenthesized string
5982 constant, warn if pedantic that EXPR is being used to initialize an
5983 object of type TYPE. */
5985 void
5987 {
5994 }
5996 /* Digest the parser output INIT as an initializer for type TYPE.
5997 Return a C expression of type TYPE to represent the initial value.
5999 If ORIGTYPE is not NULL_TREE, it is the original type of INIT.
6001 NULL_POINTER_CONSTANT is true if INIT is a null pointer constant.
6003 If INIT is a string constant, STRICT_STRING is true if it is
6004 unparenthesized or we should not warn here for it being parenthesized.
6005 For other types of INIT, STRICT_STRING is not used.
6007 INIT_LOC is the location of the INIT.
6009 REQUIRE_CONSTANT requests an error if non-constant initializers or
6010 elements are seen. */
6012 static tree
6016 {
6023 || !init
6031 {
6034 }
6038 /* Initialization of an array of chars from a string constant
6039 optionally enclosed in braces. */
6043 {
6045 /* Note that an array could be both an array of character type
6046 and an array of wchar_t if wchar_t is signed char or unsigned
6047 char. */
6056 {
6073 {
6075 {
6078 }
6079 }
6080 else
6081 {
6083 {
6087 }
6089 {
6093 }
6094 }
6100 {
6103 /* Subtract the size of a single (possibly wide) character
6104 because it's ok to ignore the terminating null char
6105 that is counted in the length of the constant. */
6107 (len
6118 }
6121 }
6123 {
6127 }
6128 }
6130 /* Build a VECTOR_CST from a *constant* vector constructor. If the
6131 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
6132 below and handle as a constructor. */
6137 {
6144 {
6146 tree value;
6149 /* Iterate through elements and check if all constructor
6150 elements are *_CSTs. */
6153 {
6156 }
6161 }
6162 }
6167 /* Any type can be initialized
6168 from an expression of the same type, optionally with braces. */
6181 {
6183 {
6185 {
6188 inside_init = array_to_pointer_conversion
6190 else
6191 {
6194 }
6195 }
6196 }
6199 /* Although the types are compatible, we may require a
6200 conversion. */
6206 {
6207 /* As an extension, allow initializing objects with static storage
6208 duration with compound literals (which are then treated just as
6209 the brace enclosed list they contain). Also allow this for
6210 vectors, as we can only assign them with compound literals. */
6213 }
6217 {
6220 }
6222 /* Compound expressions can only occur here if -Wpedantic or
6223 -pedantic-errors is specified. In the later case, we always want
6224 an error. In the former case, we simply want a warning. */
6227 {
6228 inside_init
6233 else
6238 }
6242 {
6245 }
6250 /* Added to enable additional -Wsuggest-attribute=format warnings. */
6253 origtype,
6257 }
6259 /* Handle scalar types, including conversions. */
6264 {
6271 inside_init);
6272 inside_init
6277 /* Check to see if we have already given an error message. */
6279 ;
6281 {
6284 }
6288 {
6291 }
6297 }
6299 /* Come here only for records and arrays. */
6302 {
6305 }
6309 }
6310 \f
6311 /* Handle initializers that use braces. */
6313 /* Type of object we are accumulating a constructor for.
6314 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
6317 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
6318 left to fill. */
6321 /* For an ARRAY_TYPE, this is the specified index
6322 at which to store the next element we get. */
6325 /* For an ARRAY_TYPE, this is the maximum index. */
6328 /* For a RECORD_TYPE, this is the first field not yet written out. */
6331 /* For an ARRAY_TYPE, this is the index of the first element
6332 not yet written out. */
6335 /* In a RECORD_TYPE, the byte index of the next consecutive field.
6336 This is so we can generate gaps between fields, when appropriate. */
6339 /* If we are saving up the elements rather than allocating them,
6340 this is the list of elements so far (in reverse order,
6341 most recent first). */
6344 /* 1 if constructor should be incrementally stored into a constructor chain,
6345 0 if all the elements should be kept in AVL tree. */
6348 /* 1 if so far this constructor's elements are all compile-time constants. */
6351 /* 1 if so far this constructor's elements are all valid address constants. */
6354 /* 1 if this constructor has an element that cannot be part of a
6355 constant expression. */
6358 /* 1 if this constructor is erroneous so far. */
6361 /* Structure for managing pending initializer elements, organized as an
6362 AVL tree. */
6364 struct init_node
6365 {
6369 tree purpose;
6370 tree value;
6371 tree origtype;
6372 };
6374 /* Tree of pending elements at this constructor level.
6375 These are elements encountered out of order
6376 which belong at places we haven't reached yet in actually
6377 writing the output.
6378 Will never hold tree nodes across GC runs. */
6381 /* The SPELLING_DEPTH of this constructor. */
6384 /* DECL node for which an initializer is being read.
6385 0 means we are reading a constructor expression
6386 such as (struct foo) {...}. */
6389 /* Nonzero if this is an initializer for a top-level decl. */
6392 /* Nonzero if there were any member designators in this initializer. */
6395 /* Nesting depth of designator list. */
6398 /* Nonzero if there were diagnosed errors in this designator list. */
6401 \f
6402 /* This stack has a level for each implicit or explicit level of
6403 structuring in the initializer, including the outermost one. It
6404 saves the values of most of the variables above. */
6408 struct constructor_stack
6409 {
6411 tree type;
6412 tree fields;
6413 tree index;
6414 tree max_index;
6415 tree unfilled_index;
6416 tree unfilled_fields;
6417 tree bit_index;
6422 /* If value nonzero, this value should replace the entire
6423 constructor at this level. */
6434 };
6438 /* This stack represents designators from some range designator up to
6439 the last designator in the list. */
6441 struct constructor_range_stack
6442 {
6445 tree range_start;
6446 tree index;
6447 tree range_end;
6448 tree fields;
6449 };
6453 /* This stack records separate initializers that are nested.
6454 Nested initializers can't happen in ANSI C, but GNU C allows them
6455 in cases like { ... (struct foo) { ... } ... }. */
6457 struct initializer_stack
6458 {
6460 tree decl;
6470 };
6473 \f
6474 /* Prepare to parse and output the initializer for variable DECL. */
6476 void
6478 {
6500 {
6502 require_constant_elements
6504 /* For a scalar, you can always use any value to initialize,
6505 even within braces. */
6511 }
6512 else
6513 {
6517 }
6530 }
6532 void
6534 {
6537 /* Free the whole constructor stack of this initializer. */
6539 {
6543 }
6547 /* Pop back to the data of the outer initializer (if any). */
6562 }
6563 \f
6564 /* Call here when we see the initializer is surrounded by braces.
6565 This is instead of a call to push_init_level;
6566 it is matched by a call to pop_init_level.
6568 TYPE is the type to initialize, for a constructor expression.
6569 For an initializer for a decl, TYPE is zero. */
6571 void
6573 {
6622 {
6624 /* Skip any nameless bit fields at the beginning. */
6631 }
6633 {
6635 {
6636 constructor_max_index
6639 /* Detect non-empty initializations of zero-length arrays. */
6644 /* constructor_max_index needs to be an INTEGER_CST. Attempts
6645 to initialize VLAs will cause a proper error; avoid tree
6646 checking errors as well by setting a safe value. */
6651 constructor_index
6654 }
6655 else
6656 {
6659 }
6662 }
6664 {
6665 /* Vectors are like simple fixed-size arrays. */
6666 constructor_max_index =
6670 }
6671 else
6672 {
6673 /* Handle the case of int x = {5}; */
6676 }
6677 }
6678 \f
6679 /* Push down into a subobject, for initialization.
6680 If this is for an explicit set of braces, IMPLICIT is 0.
6681 If it is because the next element belongs at a lower level,
6682 IMPLICIT is 1 (or 2 if the push is because of designator list). */
6684 void
6686 {
6690 /* If we've exhausted any levels that didn't have braces,
6691 pop them now. If implicit == 1, this will have been done in
6692 process_init_element; do not repeat it here because in the case
6693 of excess initializers for an empty aggregate this leads to an
6694 infinite cycle of popping a level and immediately recreating
6695 it. */
6697 {
6699 {
6706 && constructor_max_index
6708 constructor_index))
6711 else
6713 }
6714 }
6716 /* Unless this is an explicit brace, we need to preserve previous
6717 content if any. */
6719 {
6726 }
6763 {
6768 }
6770 /* Don't die if an entire brace-pair level is superfluous
6771 in the containing level. */
6773 ;
6776 {
6777 /* Don't die if there are extra init elts at the end. */
6780 else
6781 {
6784 constructor_depth++;
6785 }
6786 }
6788 {
6791 constructor_depth++;
6792 }
6795 {
6800 }
6803 {
6812 }
6815 {
6818 }
6822 {
6824 /* Skip any nameless bit fields at the beginning. */
6831 }
6833 {
6834 /* Vectors are like simple fixed-size arrays. */
6835 constructor_max_index =
6839 }
6841 {
6843 {
6844 constructor_max_index
6847 /* Detect non-empty initializations of zero-length arrays. */
6852 /* constructor_max_index needs to be an INTEGER_CST. Attempts
6853 to initialize VLAs will cause a proper error; avoid tree
6854 checking errors as well by setting a safe value. */
6859 constructor_index
6862 }
6863 else
6868 {
6869 /* We need to split the char/wchar array into individual
6870 characters, so that we don't have to special case it
6871 everywhere. */
6873 }
6874 }
6875 else
6876 {
6881 }
6882 }
6884 /* At the end of an implicit or explicit brace level,
6885 finish up that level of constructor. If a single expression
6886 with redundant braces initialized that level, return the
6887 c_expr structure for that expression. Otherwise, the original_code
6888 element is set to ERROR_MARK.
6889 If we were outputting the elements as they are read, return 0 as the value
6890 from inner levels (process_init_element ignores that),
6891 but return error_mark_node as the value from the outermost level
6892 (that's what we want to put in DECL_INITIAL).
6893 Otherwise, return a CONSTRUCTOR expression as the value. */
6895 struct c_expr
6897 {
6905 {
6906 /* When we come to an explicit close brace,
6907 pop any inner levels that didn't have explicit braces. */
6909 {
6912 }
6914 }
6916 /* Now output all pending elements. */
6922 /* Error for initializing a flexible array member, or a zero-length
6923 array member in an inappropriate context. */
6928 {
6929 /* Silently discard empty initializations. The parser will
6930 already have pedwarned for empty brackets. */
6933 else
6934 {
6939 else
6943 /* We have already issued an error message for the existence
6944 of a flexible array member not at the end of the structure.
6945 Discard the initializer so that we do not die later. */
6948 }
6949 }
6951 /* Warn when some struct elements are implicitly initialized to zero. */
6953 && constructor_type
6956 {
6961 /* Do not warn for flexible array members or zero-length arrays. */
6968 /* Do not warn if this level of the initializer uses member
6969 designators; it is likely to be deliberate. */
6970 && !constructor_designated
6971 /* Do not warn about initializing with ` = {0}'. */
6973 {
6976 constructor_unfilled_fields,
6977 constructor_type))
6980 }
6981 }
6983 /* Pad out the end of the structure. */
6985 /* If this closes a superfluous brace pair,
6986 just pass out the element between them. */
6989 ;
6994 {
6995 /* A nonincremental scalar initializer--just return
6996 the element, after verifying there is just one. */
6998 {
7002 }
7004 {
7007 }
7008 else
7010 }
7011 else
7012 {
7015 else
7016 {
7018 constructor_elements);
7025 }
7026 }
7029 {
7034 }
7062 }
7064 /* Common handling for both array range and field name designators.
7065 ARRAY argument is nonzero for array ranges. Returns zero for success. */
7067 static int
7069 {
7070 tree subtype;
7073 /* Don't die if an entire brace-pair level is superfluous
7074 in the containing level. */
7078 /* If there were errors in this designator list already, bail out
7079 silently. */
7084 {
7087 /* Designator list starts at the level of closest explicit
7088 braces. */
7090 {
7093 }
7096 }
7099 {
7111 }
7115 {
7118 }
7120 {
7123 }
7128 }
7130 /* If there are range designators in designator list, push a new designator
7131 to constructor_range_stack. RANGE_END is end of such stack range or
7132 NULL_TREE if there is no range designator at this level. */
7134 static void
7136 {
7152 }
7154 /* Within an array initializer, specify the next index to be initialized.
7155 FIRST is that index. If LAST is nonzero, then initialize a range
7156 of indices, running from FIRST through LAST. */
7158 void
7161 {
7169 {
7172 }
7175 {
7179 "array index in initializer is not "
7181 }
7184 {
7188 "array index in initializer is not "
7190 }
7203 else
7204 {
7211 {
7215 {
7218 }
7219 else
7220 {
7224 {
7227 }
7228 }
7229 }
7231 designator_depth++;
7235 }
7236 }
7238 /* Within a struct initializer, specify the next field to be initialized. */
7240 void
7242 {
7243 tree field;
7252 {
7255 }
7261 else
7262 do
7263 {
7265 designator_depth++;
7271 {
7274 }
7275 }
7277 }
7278 \f
7279 /* Add a new initializer to the tree of pending initializers. PURPOSE
7280 identifies the initializer, either array index or field in a structure.
7281 VALUE is the value of that index or field. If ORIGTYPE is not
7282 NULL_TREE, it is the original type of VALUE.
7284 IMPLICIT is true if value comes from pop_init_level (1),
7285 the new initializer has been merged with the existing one
7286 and thus no warnings should be emitted about overriding an
7287 existing initializer. */
7289 static void
7292 {
7299 {
7301 {
7307 else
7308 {
7310 {
7315 }
7319 }
7320 }
7321 }
7322 else
7323 {
7324 tree bitpos;
7328 {
7334 else
7335 {
7337 {
7342 }
7346 }
7347 }
7348 }
7363 {
7367 {
7371 {
7373 {
7374 /* L rotation. */
7387 {
7390 else
7392 }
7393 else
7395 }
7396 else
7397 {
7398 /* LR rotation. */
7420 {
7423 else
7425 }
7426 else
7428 }
7430 }
7431 else
7432 {
7433 /* p->balance == +1; growth of left side balances the node. */
7436 }
7437 }
7439 {
7441 /* Growth propagation from right side. */
7444 {
7446 {
7447 /* R rotation. */
7460 {
7463 else
7465 }
7466 else
7468 }
7470 {
7471 /* RL rotation */
7493 {
7496 else
7498 }
7499 else
7501 }
7503 }
7504 else
7505 {
7506 /* p->balance == -1; growth of right side balances the node. */
7509 }
7510 }
7514 }
7515 }
7517 /* Build AVL tree from a sorted chain. */
7519 static void
7521 {
7530 {
7532 braced_init_obstack);
7533 }
7536 {
7538 /* Skip any nameless bit fields at the beginning. */
7544 }
7546 {
7548 constructor_unfilled_index
7551 else
7553 }
7555 }
7557 /* Build AVL tree from a string constant. */
7559 static void
7562 {
7577 p < end
7578 && !(constructor_max_index
7581 {
7583 {
7586 }
7587 else
7588 {
7592 {
7595 else
7600 }
7601 }
7604 {
7607 {
7609 {
7612 }
7613 }
7615 {
7618 }
7623 }
7627 braced_init_obstack);
7628 }
7631 }
7633 /* Return value of FIELD in pending initializer or zero if the field was
7634 not initialized yet. */
7636 static tree
7638 {
7642 {
7649 {
7654 else
7656 }
7657 }
7659 {
7663 && (!constructor_unfilled_fields
7670 {
7675 else
7677 }
7678 }
7680 {
7684 }
7686 }
7688 /* "Output" the next constructor element.
7689 At top level, really output it to assembler code now.
7690 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
7691 If ORIGTYPE is not NULL_TREE, it is the original type of VALUE.
7692 TYPE is the data type that the containing data type wants here.
7693 FIELD is the field (a FIELD_DECL) or the index that this element fills.
7694 If VALUE is a string constant, STRICT_STRING is true if it is
7695 unparenthesized or we should not warn here for it being parenthesized.
7696 For other types of VALUE, STRICT_STRING is not used.
7698 PENDING if non-nil means output pending elements that belong
7699 right after this element. (PENDING is normally 1;
7700 it is 0 while outputting pending elements, to avoid recursion.)
7702 IMPLICIT is true if value comes from pop_init_level (1),
7703 the new initializer has been merged with the existing one
7704 and thus no warnings should be emitted about overriding an
7705 existing initializer. */
7707 static void
7711 {
7717 {
7720 }
7733 {
7734 /* As an extension, allow initializing objects with static storage
7735 duration with compound literals (which are then treated just as
7736 the brace enclosed list they contain). */
7739 }
7743 {
7746 }
7763 {
7765 {
7768 }
7772 }
7778 /* Issue -Wc++-compat warnings about initializing a bitfield with
7779 enum type. */
7787 {
7794 }
7796 /* If this field is empty (and not at the end of structure),
7797 don't do anything other than checking the initializer. */
7811 {
7814 }
7818 /* If this element doesn't come next in sequence,
7819 put it on constructor_pending_elts. */
7821 && (!constructor_incremental
7823 {
7829 braced_init_obstack);
7831 }
7833 && (!constructor_incremental
7835 {
7836 /* We do this for records but not for unions. In a union,
7837 no matter which field is specified, it can be initialized
7838 right away since it starts at the beginning of the union. */
7840 {
7843 else
7844 {
7852 }
7853 }
7856 braced_init_obstack);
7858 }
7861 {
7863 {
7869 }
7871 /* We can have just one union field set. */
7873 }
7875 /* Otherwise, output this element either to
7876 constructor_elements or to the assembler file. */
7881 /* Advance the variable that indicates sequential elements output. */
7883 constructor_unfilled_index
7885 bitsize_one_node);
7887 {
7888 constructor_unfilled_fields
7891 /* Skip any nameless bit fields. */
7895 constructor_unfilled_fields =
7897 }
7901 /* Now output any pending elements which have become next. */
7904 }
7906 /* Output any pending elements which have become next.
7907 As we output elements, constructor_unfilled_{fields,index}
7908 advances, which may cause other elements to become next;
7909 if so, they too are output.
7911 If ALL is 0, we return when there are
7912 no more pending elements to output now.
7914 If ALL is 1, we output space as necessary so that
7915 we can output all the pending elements. */
7916 static void
7918 {
7920 tree next;
7922 retry:
7924 /* Look through the whole pending tree.
7925 If we find an element that should be output now,
7926 output it. Otherwise, set NEXT to the element
7927 that comes first among those still pending. */
7931 {
7933 {
7935 constructor_unfilled_index))
7939 braced_init_obstack);
7942 {
7943 /* Advance to the next smaller node. */
7946 else
7947 {
7948 /* We have reached the smallest node bigger than the
7949 current unfilled index. Fill the space first. */
7952 }
7953 }
7954 else
7955 {
7956 /* Advance to the next bigger node. */
7959 else
7960 {
7961 /* We have reached the biggest node in a subtree. Find
7962 the parent of it, which is the next bigger node. */
7968 {
7971 }
7972 }
7973 }
7974 }
7977 {
7980 /* If the current record is complete we are done. */
7986 /* We can't compare fields here because there might be empty
7987 fields in between. */
7989 {
7994 braced_init_obstack);
7995 }
7997 {
7998 /* Advance to the next smaller node. */
8001 else
8002 {
8003 /* We have reached the smallest node bigger than the
8004 current unfilled field. Fill the space first. */
8007 }
8008 }
8009 else
8010 {
8011 /* Advance to the next bigger node. */
8014 else
8015 {
8016 /* We have reached the biggest node in a subtree. Find
8017 the parent of it, which is the next bigger node. */
8024 {
8027 }
8028 }
8029 }
8030 }
8031 }
8033 /* Ordinarily return, but not if we want to output all
8034 and there are elements left. */
8038 /* If it's not incremental, just skip over the gap, so that after
8039 jumping to retry we will output the next successive element. */
8046 /* ELT now points to the node in the pending tree with the next
8047 initializer to output. */
8049 }
8050 \f
8051 /* Add one non-braced element to the current constructor level.
8052 This adjusts the current position within the constructor's type.
8053 This may also start or terminate implicit levels
8054 to handle a partly-braced initializer.
8056 Once this has found the correct level for the new element,
8057 it calls output_init_element.
8059 IMPLICIT is true if value comes from pop_init_level (1),
8060 the new initializer has been merged with the existing one
8061 and thus no warnings should be emitted about overriding an
8062 existing initializer. */
8064 void
8067 {
8075 /* Handle superfluous braces around string cst as in
8076 char x[] = {"foo"}; */
8078 && constructor_type
8082 {
8087 }
8090 {
8093 }
8095 /* Ignore elements of a brace group if it is entirely superfluous
8096 and has already been diagnosed. */
8100 /* If we've exhausted any levels that didn't have braces,
8101 pop them now. */
8103 {
8111 && constructor_max_index
8113 constructor_index))
8116 else
8118 }
8120 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
8122 {
8123 /* If value is a compound literal and we'll be just using its
8124 content, don't put it into a SAVE_EXPR. */
8126 || !require_constant_value
8128 {
8131 {
8134 }
8139 }
8140 }
8143 {
8145 {
8146 tree fieldtype;
8150 {
8154 }
8161 /* Error for non-static initialization of a flexible array member. */
8163 && !require_constant_value
8166 {
8169 }
8171 /* Accept a string constant to initialize a subarray. */
8177 /* Otherwise, if we have come to a subaggregate,
8178 and we don't have an element of its type, push into it. */
8184 {
8187 }
8190 {
8195 braced_init_obstack);
8197 }
8198 else
8199 /* Do the bookkeeping for an element that was
8200 directly output as a constructor. */
8201 {
8202 /* For a record, keep track of end position of last field. */
8204 constructor_bit_index
8209 /* If the current field was the first one not yet written out,
8210 it isn't now, so update. */
8212 {
8214 /* Skip any nameless bit fields. */
8218 constructor_unfilled_fields =
8220 }
8221 }
8224 /* Skip any nameless bit fields at the beginning. */
8229 }
8231 {
8232 tree fieldtype;
8236 {
8240 }
8247 /* Warn that traditional C rejects initialization of unions.
8248 We skip the warning if the value is zero. This is done
8249 under the assumption that the zero initializer in user
8250 code appears conditioned on e.g. __STDC__ to avoid
8251 "missing initializer" warnings and relies on default
8252 initialization to zero in the traditional C case.
8253 We also skip the warning if the initializer is designated,
8254 again on the assumption that this must be conditional on
8255 __STDC__ anyway (and we've already complained about the
8256 member-designator already). */
8263 /* Accept a string constant to initialize a subarray. */
8269 /* Otherwise, if we have come to a subaggregate,
8270 and we don't have an element of its type, push into it. */
8276 {
8279 }
8282 {
8287 braced_init_obstack);
8289 }
8290 else
8291 /* Do the bookkeeping for an element that was
8292 directly output as a constructor. */
8293 {
8296 }
8299 }
8301 {
8305 /* Accept a string constant to initialize a subarray. */
8311 /* Otherwise, if we have come to a subaggregate,
8312 and we don't have an element of its type, push into it. */
8318 {
8321 }
8326 {
8330 }
8332 /* Now output the actual element. */
8334 {
8339 braced_init_obstack);
8341 }
8343 constructor_index
8348 /* If we are doing the bookkeeping for an element that was
8349 directly output as a constructor, we must update
8350 constructor_unfilled_index. */
8352 }
8354 {
8357 /* Do a basic check of initializer size. Note that vectors
8358 always have a fixed size derived from their type. */
8360 {
8364 }
8366 /* Now output the actual element. */
8368 {
8374 braced_init_obstack);
8375 }
8377 constructor_index
8382 /* If we are doing the bookkeeping for an element that was
8383 directly output as a constructor, we must update
8384 constructor_unfilled_index. */
8386 }
8388 /* Handle the sole element allowed in a braced initializer
8389 for a scalar variable. */
8392 {
8396 }
8397 else
8398 {
8403 braced_init_obstack);
8405 }
8407 /* Handle range initializers either at this level or anywhere higher
8408 in the designator stack. */
8410 {
8417 {
8420 braced_init_obstack),
8422 }
8426 {
8430 }
8438 {
8442 {
8445 }
8453 }
8458 }
8461 }
8464 }
8465 \f
8466 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
8467 (guaranteed to be 'volatile' or null) and ARGS (represented using
8468 an ASM_EXPR node). */
8469 tree
8471 {
8475 }
8477 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
8478 some INPUTS, and some CLOBBERS. The latter three may be NULL.
8479 SIMPLE indicates whether there was anything at all after the
8480 string in the asm expression -- asm("blah") and asm("blah" : )
8481 are subtly different. We use a ASM_EXPR node to represent this. */
8482 tree
8485 {
8486 tree tail;
8487 tree args;
8500 /* Remove output conversions that change the type but not the mode. */
8502 {
8507 /* ??? Really, this should not be here. Users should be using a
8508 proper lvalue, dammit. But there's a long history of using casts
8509 in the output operands. In cases like longlong.h, this becomes a
8510 primitive form of typechecking -- if the cast can be removed, then
8511 the output operand had a type of the proper width; otherwise we'll
8512 get an error. Gross, but ... */
8531 {
8532 /* If the operand is going to end up in memory,
8533 mark it addressable. */
8539 {
8542 }
8543 }
8544 else
8548 }
8551 {
8552 tree input;
8559 {
8560 /* If the operand is going to end up in memory,
8561 mark it addressable. */
8563 {
8566 /* Strip the nops as we allow this case. FIXME, this really
8567 should be rejected or made deprecated. */
8571 }
8572 else
8573 {
8581 {
8584 }
8585 }
8586 }
8587 else
8591 }
8593 /* ASMs with labels cannot have outputs. This should have been
8594 enforced by the parser. */
8599 /* asm statements without outputs, including simple ones, are treated
8600 as volatile. */
8605 }
8606 \f
8607 /* Generate a goto statement to LABEL. LOC is the location of the
8608 GOTO. */
8610 tree
8612 {
8617 {
8621 }
8622 }
8624 /* Generate a computed goto statement to EXPR. LOC is the location of
8625 the GOTO. */
8627 tree
8629 {
8630 tree t;
8637 }
8639 /* Generate a C `return' statement. RETVAL is the expression for what
8640 to return, or a null pointer for `return;' with no value. LOC is
8641 the location of the return statement. If ORIGTYPE is not NULL_TREE, it
8642 is the original type of RETVAL. */
8644 tree
8646 {
8656 {
8660 {
8663 }
8667 }
8670 {
8674 {
8676 "%<return%> with no value, in "
8679 }
8680 }
8682 {
8687 else
8690 }
8691 else
8692 {
8694 ic_return,
8697 tree inner;
8711 /* Strip any conversions, additions, and subtractions, and see if
8712 we are returning the address of a local variable. Warn if so. */
8714 {
8716 {
8717 CASE_CONVERT:
8725 /* If the second operand of the MINUS_EXPR has a pointer
8726 type (or is converted from it), this may be valid, so
8727 don't give a warning. */
8728 {
8741 }
8761 }
8764 }
8771 }
8776 }
8777 \f
8779 /* The SWITCH_EXPR being built. */
8780 tree switch_expr;
8782 /* The original type of the testing expression, i.e. before the
8783 default conversion is applied. */
8784 tree orig_type;
8786 /* A splay-tree mapping the low element of a case range to the high
8787 element, or NULL_TREE if there is no high element. Used to
8788 determine whether or not a new case label duplicates an old case
8789 label. We need a tree, rather than simply a hash table, because
8790 of the GNU case range extension. */
8791 splay_tree cases;
8793 /* The bindings at the point of the switch. This is used for
8794 warnings crossing decls when branching to a case label. */
8797 /* The next node on the stack. */
8799 };
8801 /* A stack of the currently active switch statements. The innermost
8802 switch statement is on the top of the stack. There is no need to
8803 mark the stack for garbage collection because it is only active
8804 during the processing of the body of a function, and we never
8805 collect at that point. */
8809 /* Start a C switch statement, testing expression EXP. Return the new
8810 SWITCH_EXPR. SWITCH_LOC is the location of the `switch'.
8811 SWITCH_COND_LOC is the location of the switch's condition. */
8813 tree
8815 location_t switch_cond_loc,
8816 tree exp)
8817 {
8822 {
8826 {
8828 {
8831 }
8833 }
8834 else
8835 {
8850 }
8851 }
8853 /* Add this new SWITCH_EXPR to the stack. */
8864 }
8866 /* Process a case label at location LOC. */
8868 tree
8870 {
8874 {
8879 }
8882 {
8887 }
8890 {
8893 else
8896 }
8900 loc))
8910 }
8912 /* Finish the switch statement. */
8914 void
8916 {
8918 location_t switch_location;
8922 /* Emit warnings as needed. */
8928 /* Pop the stack. */
8933 }
8934 \f
8935 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
8936 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
8937 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
8938 statement, and was not surrounded with parenthesis. */
8940 void
8943 {
8944 tree stmt;
8946 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
8948 {
8951 /* We know from the grammar productions that there is an IF nested
8952 within THEN_BLOCK. Due to labels and c99 conditional declarations,
8953 it might not be exactly THEN_BLOCK, but should be the last
8954 non-container statement within. */
8957 {
8972 }
8973 found:
8978 }
8983 }
8985 /* Emit a general-purpose loop construct. START_LOCUS is the location of
8986 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
8987 is false for DO loops. INCR is the FOR increment expression. BODY is
8988 the statement controlled by the loop. BLAB is the break label. CLAB is
8989 the continue label. Everything is allowed to be NULL. */
8991 void
8994 {
8997 /* If the condition is zero don't generate a loop construct. */
8999 {
9001 {
9005 }
9006 }
9007 else
9008 {
9011 /* If we have an exit condition, then we build an IF with gotos either
9012 out of the loop, or to the top of it. If there's no exit condition,
9013 then we just build a jump back to the top. */
9017 {
9018 /* Canonicalize the loop condition to the end. This means
9019 generating a branch to the loop condition. Reuse the
9020 continue label, if possible. */
9022 {
9024 {
9027 }
9028 else
9032 }
9038 else
9041 }
9044 }
9058 }
9060 tree
9062 {
9066 /* In switch statements break is sometimes stylistically used after
9067 a return statement. This can lead to spurious warnings about
9068 control reaching the end of a non-void function when it is
9069 inlined. Note that we are calling block_may_fallthru with
9070 language specific tree nodes; this works because
9071 block_may_fallthru returns true when given something it does not
9072 understand. */
9076 {
9079 }
9081 ;
9083 {
9087 else
9098 }
9107 }
9109 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
9111 static void
9113 {
9115 ;
9117 {
9120 }
9121 else
9123 }
9125 /* Process an expression as if it were a complete statement. Emit
9126 diagnostics, but do not call ADD_STMT. LOC is the location of the
9127 statement. */
9129 tree
9131 {
9132 tree exprv;
9147 /* If we're not processing a statement expression, warn about unused values.
9148 Warnings for statement expressions will be emitted later, once we figure
9149 out which is the result. */
9164 /* If the expression is not of a type to which we cannot assign a line
9165 number, wrap the thing in a no-op NOP_EXPR. */
9167 {
9170 }
9173 }
9175 /* Emit an expression as a statement. LOC is the location of the
9176 expression. */
9178 tree
9180 {
9183 else
9185 }
9187 /* Do the opposite and emit a statement as an expression. To begin,
9188 create a new binding level and return it. */
9190 tree
9192 {
9193 tree ret;
9195 /* We must force a BLOCK for this level so that, if it is not expanded
9196 later, there is a way to turn off the entire subtree of blocks that
9197 are contained in it. */
9202 ? NULL
9205 /* Mark the current statement list as belonging to a statement list. */
9209 }
9211 /* LOC is the location of the compound statement to which this body
9212 belongs. */
9214 tree
9216 {
9223 ? NULL
9226 /* Locate the last statement in BODY. See c_end_compound_stmt
9227 about always returning a BIND_EXPR. */
9231 continue_searching:
9233 {
9234 tree_stmt_iterator i;
9236 /* This can happen with degenerate cases like ({ }). No value. */
9240 /* If we're supposed to generate side effects warnings, process
9241 all of the statements except the last. */
9243 {
9245 {
9246 location_t tloc;
9251 }
9252 }
9253 else
9257 }
9259 /* If the end of the list is exception related, then the list was split
9260 by a call to push_cleanup. Continue searching. */
9263 {
9267 }
9272 /* In the case that the BIND_EXPR is not necessary, return the
9273 expression out from inside it. */
9276 {
9277 /* Even if this looks constant, do not allow it in a constant
9278 expression. */
9280 /* Do not warn if the return value of a statement expression is
9281 unused. */
9284 }
9286 /* Extract the type of said expression. */
9289 /* If we're not returning a value at all, then the BIND_EXPR that
9290 we already have is a fine expression to return. */
9294 /* Now that we've located the expression containing the value, it seems
9295 silly to make voidify_wrapper_expr repeat the process. Create a
9296 temporary of the appropriate type and stick it in a TARGET_EXPR. */
9299 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
9300 tree_expr_nonnegative_p giving up immediately. */
9309 {
9313 }
9314 }
9315 \f
9316 /* Begin and end compound statements. This is as simple as pushing
9317 and popping new statement lists from the tree. */
9319 tree
9321 {
9326 }
9328 /* End a compound statement. STMT is the statement. LOC is the
9329 location of the compound statement-- this is usually the location
9330 of the opening brace. */
9332 tree
9334 {
9338 {
9342 }
9347 /* If this compound statement is nested immediately inside a statement
9348 expression, then force a BIND_EXPR to be created. Otherwise we'll
9349 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
9350 STATEMENT_LISTs merge, and thus we can lose track of what statement
9351 was really last. */
9355 {
9359 }
9362 }
9364 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
9365 when the current scope is exited. EH_ONLY is true when this is not
9366 meant to apply to normal control flow transfer. */
9368 void
9370 {
9382 }
9383 \f
9384 /* Build a binary-operation expression without default conversions.
9385 CODE is the kind of expression to build.
9386 LOCATION is the operator's location.
9387 This function differs from `build' in several ways:
9388 the data type of the result is computed and recorded in it,
9389 warnings are generated if arg data types are invalid,
9390 special handling for addition and subtraction of pointers is known,
9391 and some optimization is done (operations on narrow ints
9392 are done in the narrower type when that gives the same result).
9393 Constant folding is also done before the result is returned.
9395 Note that the operands will never have enumeral types, or function
9396 or array types, because either they will have the default conversions
9397 performed or they have both just been converted to some other type in which
9398 the arithmetic is to be done. */
9400 tree
9403 {
9405 tree eptype;
9413 /* Expression code to give to the expression when it is built.
9414 Normally this is CODE, which is what the caller asked for,
9415 but in some special cases we change it. */
9418 /* Data type in which the computation is to be performed.
9419 In the simplest cases this is the common type of the arguments. */
9422 /* When the computation is in excess precision, the type of the
9423 final EXCESS_PRECISION_EXPR. */
9426 /* Nonzero means operands have already been type-converted
9427 in whatever way is necessary.
9428 Zero means they need to be converted to RESULT_TYPE. */
9431 /* Nonzero means create the expression with this type, rather than
9432 RESULT_TYPE. */
9435 /* Nonzero means after finally constructing the expression
9436 convert it to this type. */
9439 /* Nonzero if this is an operation like MIN or MAX which can
9440 safely be computed in short if both args are promoted shorts.
9441 Also implies COMMON.
9442 -1 indicates a bitwise operation; this makes a difference
9443 in the exact conditions for when it is safe to do the operation
9444 in a narrower mode. */
9447 /* Nonzero if this is a comparison operation;
9448 if both args are promoted shorts, compare the original shorts.
9449 Also implies COMMON. */
9452 /* Nonzero if this is a right-shift operation, which can be computed on the
9453 original short and then promoted if the operand is a promoted short. */
9456 /* Nonzero means set RESULT_TYPE to the common type of the args. */
9459 /* True means types are compatible as far as ObjC is concerned. */
9462 /* True means this is an arithmetic operation that may need excess
9463 precision. */
9466 /* True means this is a boolean operation that converts both its
9467 operands to truth-values. */
9484 {
9487 int_const = (int_const_or_overflow
9490 }
9491 else
9494 /* Do not apply default conversion in mixed vector/scalar expression. */
9498 {
9501 }
9506 /* The expression codes of the data types of the arguments tell us
9507 whether the arguments are integers, floating, pointers, etc. */
9511 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
9515 /* If an error was already reported for one of the arguments,
9516 avoid reporting another error. */
9523 {
9526 }
9529 {
9543 }
9545 {
9548 }
9551 {
9554 }
9556 {
9559 }
9562 {
9565 }
9569 /* In case when one of the operands of the binary operation is
9570 a vector and another is a scalar -- convert scalar to vector. */
9572 {
9577 {
9581 {
9583 tree sc;
9594 }
9596 {
9598 tree sc;
9609 }
9612 }
9613 }
9616 {
9618 /* Handle the pointer + int case. */
9620 {
9623 }
9625 {
9628 }
9629 else
9634 /* Subtraction of two similar pointers.
9635 We must subtract them as integers, then divide by object size. */
9638 {
9641 }
9642 /* Handle pointer minus int. Just like pointer plus int. */
9644 {
9647 }
9648 else
9669 {
9680 else
9681 /* Although it would be tempting to shorten always here, that
9682 loses on some targets, since the modulo instruction is
9683 undefined if the quotient can't be represented in the
9684 computation mode. We shorten only if unsigned or if
9685 dividing by something we know != -1. */
9690 }
9698 /* Allow vector types which are not floating point types. */
9715 {
9716 /* Although it would be tempting to shorten always here, that loses
9717 on some targets, since the modulo instruction is undefined if the
9718 quotient can't be represented in the computation mode. We shorten
9719 only if unsigned or if dividing by something we know != -1. */
9724 }
9738 {
9739 /* Result of these operations is always an int,
9740 but that does not mean the operands should be
9741 converted to ints! */
9744 {
9747 }
9748 else
9751 {
9754 }
9755 else
9759 }
9761 {
9762 int_const_or_overflow = (int_operands
9766 int_const = (int_const_or_overflow
9770 }
9772 {
9773 int_const_or_overflow = (int_operands
9777 int_const = (int_const_or_overflow
9781 }
9784 /* Shift operations: result has same type as first operand;
9785 always convert second operand to int.
9786 Also set SHORT_SHIFT if shifting rightward. */
9791 {
9794 }
9799 {
9802 }
9805 {
9807 {
9809 {
9813 }
9814 else
9815 {
9820 {
9824 }
9825 }
9826 }
9828 /* Use the type of the value to be shifted. */
9830 /* Convert the non vector shift-count to an integer, regardless
9831 of size of value being shifted. */
9835 /* Avoid converting op1 to result_type later. */
9837 }
9843 {
9846 }
9851 {
9854 }
9857 {
9859 {
9861 {
9865 }
9868 {
9872 }
9873 }
9875 /* Use the type of the value to be shifted. */
9877 /* Convert the non vector shift-count to an integer, regardless
9878 of size of value being shifted. */
9882 /* Avoid converting op1 to result_type later. */
9884 }
9890 {
9891 tree intt;
9893 {
9897 }
9900 {
9904 }
9906 /* Always construct signed integer vector type. */
9913 }
9916 OPT_Wfloat_equal,
9918 /* Result of comparison is always int,
9919 but don't convert the args to int! */
9927 {
9930 {
9933 OPT_Waddress,
9934 "the comparison will always evaluate as %<false%> "
9937 else
9939 OPT_Waddress,
9940 "the comparison will always evaluate as %<true%> "
9943 }
9945 }
9947 {
9950 {
9953 OPT_Waddress,
9954 "the comparison will always evaluate as %<false%> "
9957 else
9959 OPT_Waddress,
9960 "the comparison will always evaluate as %<true%> "
9963 }
9965 }
9967 {
9974 /* Anything compares with void *. void * compares with anything.
9975 Otherwise, the targets must be compatible
9976 and both must be object or both incomplete. */
9980 {
9984 }
9986 {
9990 }
9992 {
9996 }
9997 else
9998 /* Avoid warning about the volatile ObjC EH puts on decls. */
10004 {
10006 result_type = build_pointer_type
10008 }
10009 }
10011 {
10014 }
10016 {
10019 }
10027 {
10028 tree intt;
10030 {
10034 }
10037 {
10041 }
10043 /* Always construct signed integer vector type. */
10050 }
10058 {
10061 addr_space_t as_common;
10064 {
10078 }
10080 {
10084 }
10085 else
10086 {
10088 result_type = build_pointer_type
10092 }
10093 }
10095 {
10103 }
10105 {
10113 }
10115 {
10118 }
10120 {
10123 }
10128 }
10137 {
10140 }
10144 &&
10147 {
10153 {
10156 "implicit conversion from %qT to %qT "
10157 "to match other operand of binary "
10159 location);
10162 }
10171 {
10172 /* An operation on mixed real/complex operands must be
10173 handled specially, but the language-independent code can
10174 more easily optimize the plain complex arithmetic if
10175 -fno-signed-zeros. */
10179 {
10182 }
10184 {
10189 }
10190 else
10191 {
10196 }
10200 {
10207 {
10212 /* Fall through. */
10219 }
10220 }
10221 else
10222 {
10229 {
10233 /* Fall through. */
10243 }
10244 }
10247 }
10249 /* For certain operations (which identify themselves by shorten != 0)
10250 if both args were extended from the same smaller type,
10251 do the arithmetic in that type and then extend.
10253 shorten !=0 and !=1 indicates a bitwise operation.
10254 For them, this optimization is safe only if
10255 both args are zero-extended or both are sign-extended.
10256 Otherwise, we might change the result.
10257 Eg, (short)-1 | (unsigned short)-1 is (int)-1
10258 but calculated in (unsigned short) it would be (unsigned short)-1. */
10261 {
10265 }
10267 /* Shifts can be shortened if shifting right. */
10270 {
10281 /* We can shorten only if the shift count is less than the
10282 number of bits in the smaller type size. */
10284 /* We cannot drop an unsigned shift after sign-extension. */
10286 {
10287 /* Do an unsigned shift if the operand was zero-extended. */
10288 result_type
10291 /* Convert value-to-be-shifted to that type. */
10295 }
10296 }
10298 /* Comparison operations are shortened too but differently.
10299 They identify themselves by setting short_compare = 1. */
10302 {
10303 /* Don't write &op0, etc., because that would prevent op0
10304 from being kept in a register.
10305 Instead, make copies of the our local variables and
10306 pass the copies by reference, then copy them back afterward. */
10309 tree val
10313 {
10316 }
10323 {
10329 {
10332 }
10333 else
10334 {
10335 /* Fold for the sake of possible warnings, as in
10336 build_conditional_expr. This requires the
10337 "original" values to be folded, not just op0 and
10338 op1. */
10339 c_inhibit_evaluation_warnings++;
10344 c_inhibit_evaluation_warnings--;
10346 require_constant_value,
10347 NULL);
10349 require_constant_value,
10350 NULL);
10351 }
10358 {
10363 }
10364 }
10365 }
10366 }
10368 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
10369 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
10370 Then the expression will be built.
10371 It will be given type FINAL_TYPE if that is nonzero;
10372 otherwise, it will be given type RESULT_TYPE. */
10375 {
10378 }
10381 {
10385 {
10388 }
10389 }
10392 {
10396 /* This can happen if one operand has a vector type, and the other
10397 has a different type. */
10400 }
10402 /* Treat expressions in initializers specially as they can't trap. */
10404 ret = (require_constant_value
10408 else
10413 return_build_binary_op:
10416 ret = (int_operands
10426 }
10429 /* Convert EXPR to be a truth-value, validating its type for this
10430 purpose. LOCATION is the source location for the expression. */
10432 tree
10434 {
10438 {
10440 error_at (location, "used array that cannot be converted to pointer where scalar is required");
10464 }
10469 {
10474 }
10475 else
10476 /* ??? Should we also give an error for vectors rather than leaving
10477 those to give errors later? */
10481 {
10484 else
10486 }
10490 }
10491 \f
10493 /* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as
10494 required. */
10496 tree
10498 {
10500 {
10502 /* Executing a compound literal inside a function reinitializes
10503 it. */
10507 }
10508 else
10510 }
10511 \f
10512 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
10514 tree
10516 {
10517 tree block;
10523 }
10525 /* Generate OMP_PARALLEL, with CLAUSES and BLOCK as its compound
10526 statement. LOC is the location of the OMP_PARALLEL. */
10528 tree
10530 {
10531 tree stmt;
10542 }
10544 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
10546 tree
10548 {
10549 tree block;
10555 }
10557 /* Generate OMP_TASK, with CLAUSES and BLOCK as its compound
10558 statement. LOC is the location of the #pragma. */
10560 tree
10562 {
10563 tree stmt;
10574 }
10576 /* For all elements of CLAUSES, validate them vs OpenMP constraints.
10577 Remove any elements from the list that are invalid. */
10579 tree
10581 {
10592 {
10598 {
10616 {
10620 }
10622 {
10627 {
10651 }
10653 {
10658 }
10659 }
10670 {
10674 }
10677 check_dup_generic:
10680 {
10684 }
10688 {
10692 }
10693 else
10703 {
10707 }
10710 {
10714 }
10715 else
10725 {
10729 }
10732 {
10736 }
10737 else
10756 }
10759 {
10763 {
10767 }
10770 {
10776 {
10780 /* const vars may be specified in firstprivate clause. */
10791 }
10793 {
10798 }
10799 }
10800 }
10804 else
10806 }
10810 }
10812 /* Create a transaction node. */
10814 tree
10816 {
10823 }
10825 /* Make a variant type in the proper way for C/C++, propagating qualifiers
10826 down to the element type of an array. */
10828 tree
10830 {
10835 {
10836 tree t;
10838 type_quals);
10840 /* See if we already have an identically qualified type. */
10842 {
10849 }
10851 {
10862 {
10863 tree unqualified_canon
10869 }
10870 else
10872 }
10874 }
10876 /* A restrict-qualified pointer type must be a pointer to object or
10877 incomplete type. Note that the use of POINTER_TYPE_P also allows
10878 REFERENCE_TYPEs, which is appropriate for C++. */
10882 {
10885 }
10888 }
10890 /* Build a VA_ARG_EXPR for the C parser. */
10892 tree
10894 {
10899 }