| blob | 0de4662bfc6ce4614a2b892133f9a37b2d14d4d1 |
1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987-2023 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. */
57 /* Possible cases of implicit conversions. Used to select diagnostic messages
58 and control folding initializers in convert_for_assignment. */
60 ic_argpass,
61 ic_assign,
62 ic_init,
63 ic_init_const,
64 ic_return
65 };
67 /* The level of nesting inside "__alignof__". */
70 /* The level of nesting inside "sizeof". */
73 /* The level of nesting inside "typeof". */
76 /* True when parsing OpenMP loop expressions. */
79 /* The argument of last parsed sizeof expression, only to be tested
80 if expr.original_code == SIZEOF_EXPR. */
81 tree c_last_sizeof_arg;
82 location_t c_last_sizeof_loc;
84 /* Nonzero if we might need to print a "missing braces around
85 initializer" message within this initializer. */
104 tree);
132 \f
133 /* Return true if EXP is a null pointer constant, false otherwise. */
135 bool
137 {
138 /* This should really operate on c_expr structures, but they aren't
139 yet available everywhere required. */
142 /* An integer constant expression with the value 0, such an expression
143 cast to type void*, or the predefined constant nullptr, are a null
144 pointer constant. */
155 }
157 /* EXPR may appear in an unevaluated part of an integer constant
158 expression, but not in an evaluated part. Wrap it in a
159 C_MAYBE_CONST_EXPR, or mark it with TREE_OVERFLOW if it is just an
160 INTEGER_CST and we cannot create a C_MAYBE_CONST_EXPR. */
162 static tree
164 {
165 tree ret;
167 {
170 }
171 else
172 {
175 }
177 }
179 /* Having checked whether EXPR may appear in an unevaluated part of an
180 integer constant expression and found that it may, remove any
181 C_MAYBE_CONST_EXPR noting this fact and return the resulting
182 expression. */
186 {
189 else
191 }
197 const_tree t1;
198 const_tree t2;
199 /* The return value of tagged_types_tu_compatible_p if we had seen
200 these two types already. */
202 };
207 /* Do `exp = require_complete_type (loc, exp);' to make sure exp
208 does not have an incomplete type. (That includes void types.)
209 LOC is the location of the use. */
211 tree
213 {
219 /* First, detect a valid value with a complete type. */
225 }
227 /* Print an error message for invalid use of an incomplete type.
228 VALUE is the expression that was used (or 0 if that isn't known)
229 and TYPE is the type that was invalid. LOC is the location for
230 the error. */
232 void
234 {
235 /* Avoid duplicate error message. */
241 else
242 {
243 retry:
244 /* We must print an error message. Be clever about what it says. */
247 {
259 {
261 {
264 }
267 }
273 }
277 else
278 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
280 }
281 }
283 /* Given a type, apply default promotions wrt unnamed function
284 arguments and return the new type. */
286 tree
288 {
294 {
295 /* Preserve unsignedness if not really getting any wider. */
299 else
301 }
309 }
311 /* Return true if between two named address spaces, whether there is a superset
312 named address space that encompasses both address spaces. If there is a
313 superset, return which address space is the superset. */
315 static bool
317 {
319 {
322 }
324 {
327 }
329 {
332 }
333 else
335 }
337 /* Return a variant of TYPE which has all the type qualifiers of LIKE
338 as well as those of TYPE. */
340 static tree
342 {
345 addr_space_t as_common;
347 /* If the two named address spaces are different, determine the common
348 superset address space. If there isn't one, raise an error. */
350 {
354 }
360 }
363 /* If NTYPE is a type of a non-variadic function with a prototype
364 and OTYPE is a type of a function without a prototype and ATTRS
365 contains attribute format, diagnosess and removes it from ATTRS.
366 Returns the result of build_type_attribute_variant of NTYPE and
367 the (possibly) modified ATTRS. */
369 static tree
371 {
375 {
377 "%qs attribute cannot be applied to a function that "
380 }
383 }
384 /* Return the composite type of two compatible types.
386 We assume that comptypes has already been done and returned
387 nonzero; if that isn't so, this may crash. In particular, we
388 assume that qualifiers match. */
390 tree
392 {
395 tree attributes;
397 /* Save time if the two types are the same. */
401 /* If one type is nonsense, use the other. */
410 /* Merge the attributes. */
413 /* If one is an enumerated type and the other is the compatible
414 integer type, the composite type might be either of the two
415 (DR#013 question 3). For consistency, use the enumerated type as
416 the composite type. */
430 {
432 /* For two pointers, do this recursively on the target type. */
433 {
440 }
443 {
446 tree unqual_elt;
453 /* We should not have any type quals on arrays at all. */
463 d1_variable = (!d1_zero
466 d2_variable = (!d2_zero
472 /* Save space: see if the result is identical to one of the args. */
485 /* Merge the element types, and have a size if either arg has
486 one. We may have qualifiers on the element types. To set
487 up TYPE_MAIN_VARIANT correctly, we need to form the
488 composite of the unqualified types and add the qualifiers
489 back at the end. */
494 && (d2_variable
495 || d2_zero
497 ? t1
499 /* Ensure a composite type involving a zero-length array type
500 is a zero-length type not an incomplete type. */
504 {
507 }
510 }
516 {
517 /* Try harder not to create a new aggregate type. */
522 }
526 /* Function types: prefer the one that specified arg types.
527 If both do, merge the arg types. Also merge the return types. */
528 {
536 /* Save space: see if the result is identical to one of the args. */
542 /* Simple way if one arg fails to specify argument types. */
544 {
549 }
551 {
556 }
558 /* If both args specify argument types, we must merge the two
559 lists, argument by argument. */
564 ;
573 {
574 /* A null type means arg type is not specified.
575 Take whatever the other function type has. */
577 {
580 }
582 {
585 }
587 /* Given wait (union {union wait *u; int *i} *)
588 and wait (union wait *),
589 prefer union wait * as type of parm. */
592 {
593 tree memb;
600 {
606 {
612 }
613 }
614 }
617 {
618 tree memb;
625 {
631 {
637 }
638 }
639 }
641 parm_done: ;
642 }
646 }
647 /* FALLTHRU */
651 }
653 }
655 /* Return the type of a conditional expression between pointers to
656 possibly differently qualified versions of compatible types.
658 We assume that comp_target_types has already been done and returned
659 true; if that isn't so, this may crash. */
661 static tree
663 {
664 tree attributes;
667 tree target;
672 /* Save time if the two types are the same. */
676 /* If one type is nonsense, use the other. */
685 /* Merge the attributes. */
688 /* Find the composite type of the target types, and combine the
689 qualifiers of the two types' targets. Do not lose qualifiers on
690 array element types by taking the TYPE_MAIN_VARIANT. */
699 /* Strip array types to get correct qualifier for pointers to arrays */
703 /* For function types do not merge const qualifiers, but drop them
704 if used inconsistently. The middle-end uses these to mark const
705 and noreturn functions. */
708 else
711 /* If the two named address spaces are different, determine the common
712 superset address space. This is guaranteed to exist due to the
713 assumption that comp_target_type returned true. */
723 }
725 /* Return the common type for two arithmetic types under the usual
726 arithmetic conversions. The default conversions have already been
727 applied, and enumerated types converted to their compatible integer
728 types. The resulting type is unqualified and has no attributes.
730 This is the type for the result of most arithmetic operations
731 if the operands have the given two types. */
733 static tree
735 {
739 /* If one type is nonsense, use the other. */
752 {
755 }
758 {
761 }
763 /* Save time if the two types are the same. */
777 /* When one operand is a decimal float type, the other operand cannot be
778 a generic float type or a complex type. We also disallow vector types
779 here. */
782 {
784 {
787 }
789 {
792 }
794 {
798 }
799 }
801 /* If one type is a vector type, return that type. (How the usual
802 arithmetic conversions apply to the vector types extension is not
803 precisely specified.) */
810 /* If one type is complex, form the common type of the non-complex
811 components, then make that complex. Use T1 or T2 if it is the
812 required type. */
814 {
824 {
828 }
829 else
831 }
833 /* If only one is real, use it as the result. */
841 /* If both are real and either are decimal floating point types, use
842 the decimal floating point type with the greater precision. */
845 {
855 }
857 /* Deal with fixed-point types. */
859 {
867 /* If one input type is saturating, the result type is saturating. */
871 /* If both fixed-point types are unsigned, the result type is unsigned.
872 When mixing fixed-point and integer types, follow the sign of the
873 fixed-point type.
874 Otherwise, the result type is signed. */
883 /* The result type is signed. */
885 {
886 /* If the input type is unsigned, we need to convert to the
887 signed type. */
889 {
895 else
899 }
901 {
907 else
911 }
912 }
915 {
918 }
919 else
920 {
922 /* Signed integers need to subtract one sign bit. */
924 }
927 {
930 }
931 else
932 {
934 /* Signed integers need to subtract one sign bit. */
936 }
941 satp);
942 }
944 /* Both real or both integers; use the one with greater precision. */
951 /* Same precision. Prefer long longs to longs to ints when the
952 same precision, following the C99 rules on integer type rank
953 (which are equivalent to the C90 rules for C90 types). */
961 {
964 else
966 }
974 {
975 /* But preserve unsignedness from the other type,
976 since long cannot hold all the values of an unsigned int. */
979 else
981 }
983 /* For floating types of the same TYPE_PRECISION (which we here
984 assume means either the same set of values, or sets of values
985 neither a subset of the other, with behavior being undefined in
986 the latter case), follow the rules from TS 18661-3: prefer
987 interchange types _FloatN, then standard types long double,
988 double, float, then extended types _FloatNx. For extended types,
989 check them starting with _Float128x as that seems most consistent
990 in spirit with preferring long double to double; for interchange
991 types, also check in that order for consistency although it's not
992 possible for more than one of them to have the same
993 precision. */
1001 /* Likewise, prefer long double to double even if same size. */
1005 /* Likewise, prefer double to float even if same size.
1006 We got a couple of embedded targets with 32 bit doubles, and the
1007 pdp11 might have 64 bit floats. */
1019 {
1020 /* Prefer any other integral types over bit-precise integer types. */
1023 /* If BITINT_TYPE is unsigned and the other type is signed
1024 non-BITINT_TYPE with the same precision, the latter has higher rank.
1025 In that case:
1026 Otherwise, both operands are converted to the unsigned integer type
1027 corresponding to the type of the operand with signed integer type. */
1030 }
1032 /* Otherwise prefer the unsigned one. */
1036 else
1038 }
1039 \f
1040 /* Wrapper around c_common_type that is used by c-common.cc and other
1041 front end optimizations that remove promotions. ENUMERAL_TYPEs
1042 are allowed here and are converted to their compatible integer types.
1043 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or
1044 preferably a non-Boolean type as the common type. */
1045 tree
1047 {
1053 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */
1058 /* If either type is BOOLEAN_TYPE, then return the other. */
1065 }
1072 };
1074 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
1075 or various other operations. Return 2 if they are compatible
1076 but a warning may be needed if you use them together. */
1078 int
1080 {
1089 }
1091 /* Like comptypes, but if it returns non-zero because enum and int are
1092 compatible, it sets *ENUM_AND_INT_P to true. */
1094 int
1096 {
1106 }
1108 /* Like comptypes, but if it returns nonzero for different types, it
1109 sets *DIFFERENT_TYPES_P to true. */
1111 int
1114 {
1124 }
1125 \f
1126 /* Return true if TYPE1 and TYPE2 are compatible types for assignment
1127 or various other operations. If they are compatible but a warning may
1128 be needed if you use them together, 'warning_needed' in DATA is set.
1129 If one type is an enum and the other a compatible integer type, then
1130 this sets 'enum_and_int_p' in DATA to true (it is never set to
1131 false). If the types are compatible but different enough not to be
1132 permitted in C11 typedef redeclarations, then this sets
1133 'different_types_p' in DATA to true; it is never set to
1134 false, but may or may not be set if the types are incompatible.
1135 This differs from comptypes, in that we don't free the seen
1136 types. */
1138 static bool
1141 {
1145 /* Suppress errors caused by previously reported errors. */
1151 /* Enumerated types are compatible with integer types, but this is
1152 not transitive: two enumerated types in the same translation unit
1153 are compatible with each other only if they are the same type. */
1158 {
1161 {
1164 }
1165 }
1169 {
1172 {
1175 }
1176 }
1181 /* Different classes of types can't be compatible. */
1186 /* Qualifiers must match. C99 6.7.3p9 */
1191 /* Allow for two different type nodes which have essentially the same
1192 definition. Note that we already checked for equality of the type
1193 qualifiers (just above). */
1201 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1209 {
1214 /* With these nodes, we can't determine type equivalence by
1215 looking at what is stored in the nodes themselves, because
1216 two nodes might have different TYPE_MAIN_VARIANTs but still
1217 represent the same type. For example, wchar_t and int could
1218 have the same properties (TYPE_PRECISION, TYPE_MIN_VALUE,
1219 TYPE_MAX_VALUE, etc.), but have different TYPE_MAIN_VARIANTs
1220 and are distinct types. On the other hand, int and the
1221 following typedef
1223 typedef int INT __attribute((may_alias));
1225 have identical properties, different TYPE_MAIN_VARIANTs, but
1226 represent the same type. The canonical type system keeps
1227 track of equivalence in this case, so we fall back on it. */
1231 /* Do not remove mode information. */
1240 {
1246 /* Target types must match incl. qualifiers. */
1252 /* Sizes must match unless one is missing or variable. */
1259 d1_variable = (!d1_zero
1262 d2_variable = (!d2_zero
1280 }
1286 {
1288 }
1297 }
1299 }
1301 /* Return true if TTL and TTR are pointers to types that are equivalent, ignoring
1302 their qualifiers, except for named address spaces. If the pointers point to
1303 different named addresses, then we must determine if one address space is a
1304 subset of the other. */
1306 static bool
1308 {
1315 addr_space_t as_common;
1318 /* Fail if pointers point to incompatible address spaces. */
1322 /* For pedantic record result of comptypes on arrays before losing
1323 qualifiers on the element type below. */
1330 /* Qualifiers on element types of array types that are
1331 pointer targets are lost by taking their TYPE_MAIN_VARIANT. */
1345 pedwarn_c11 (location, OPT_Wpedantic, "invalid use of pointers to arrays with different qualifiers "
1356 }
1357 \f
1358 /* Subroutines of `comptypes'. */
1362 /* Allocate the seen two types, assuming that they are compatible. */
1366 {
1374 /* The C standard says that two structures in different translation
1375 units are compatible with each other only if the types of their
1376 fields are compatible (among other things). We assume that they
1377 are compatible until proven otherwise when building the cache.
1378 An example where this can occur is:
1379 struct a
1380 {
1381 struct a *next;
1382 };
1383 If we are comparing this against a similar struct in another TU,
1384 and did not assume they were compatible, we end up with an infinite
1385 loop. */
1388 }
1390 /* Free the seen types until we get to TU_TIL. */
1392 static void
1394 {
1397 {
1402 }
1404 }
1406 /* Return true if two 'struct', 'union', or 'enum' types T1 and T2 are
1407 compatible. The two types are not the same (which has been
1408 checked earlier in comptypes_internal). */
1410 static bool
1413 {
1416 /* We have to verify that the tags of the types are the same. This
1417 is harder than it looks because this may be a typedef, so we have
1418 to go look at the original type. It may even be a typedef of a
1419 typedef...
1420 In the case of compiler-created builtin structs the TYPE_DECL
1421 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
1432 /* C90 didn't have the requirement that the two tags be the same. */
1436 /* C90 didn't say what happened if one or both of the types were
1437 incomplete; we choose to follow C99 rules here, which is that they
1438 are compatible. */
1443 {
1448 }
1451 {
1453 {
1455 /* Speed up the case where the type values are in the same order. */
1460 {
1462 }
1465 {
1469 {
1472 }
1473 }
1476 {
1478 }
1480 {
1483 }
1486 {
1489 }
1492 {
1496 {
1499 }
1500 }
1502 }
1505 {
1509 {
1512 }
1514 /* Speed up the common case where the fields are in the same order. */
1517 {
1527 {
1530 }
1535 {
1538 }
1539 }
1541 {
1543 }
1546 {
1551 {
1555 data);
1560 {
1563 }
1572 }
1574 {
1577 }
1578 }
1580 }
1583 {
1587 {
1590 }
1595 {
1608 }
1611 else
1614 }
1618 }
1619 }
1621 /* Return true if two function types F1 and F2 are compatible.
1622 If either type specifies no argument types,
1623 the other must specify a fixed number of self-promoting arg types.
1624 Otherwise, if one type specifies only the number of arguments,
1625 the other must specify that number of self-promoting arg types.
1626 Otherwise, the argument types must match. */
1628 static bool
1631 {
1633 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1641 /* 'volatile' qualifiers on a function's return type used to mean
1642 the function is noreturn. */
1661 /* An unspecified parmlist matches any specified parmlist
1662 whose argument types don't need default promotions. */
1665 {
1670 /* If one of these types comes from a non-prototype fn definition,
1671 compare that with the other type's arglist.
1672 If they don't match, ask for a warning (but no error). */
1676 {
1679 }
1681 }
1683 {
1691 {
1694 }
1696 }
1698 /* Both types have argument lists: compare them and propagate results. */
1701 }
1703 /* Check two lists of types for compatibility, returning false for
1704 incompatible, true for compatible. */
1706 static bool
1709 {
1711 {
1715 /* If one list is shorter than the other,
1716 they fail to match. */
1724 TYPE_QUAL_ATOMIC)
1729 TYPE_QUAL_ATOMIC)
1731 /* A null pointer instead of a type
1732 means there is supposed to be an argument
1733 but nothing is specified about what type it has.
1734 So match anything that self-promotes. */
1738 {
1741 }
1743 {
1746 }
1747 /* If one of the lists has an error marker, ignore this arg. */
1750 ;
1752 {
1754 /* Allow wait (union {union wait *u; int *i} *)
1755 and wait (union wait *) to be compatible. */
1762 {
1763 tree memb;
1766 {
1772 TYPE_QUAL_ATOMIC)
1776 }
1779 }
1786 {
1787 tree memb;
1790 {
1796 TYPE_QUAL_ATOMIC)
1800 }
1803 }
1804 else
1806 }
1810 }
1811 }
1812 \f
1813 /* Compute the size to increment a pointer by. When a function type or void
1814 type or incomplete type is passed, size_one_node is returned.
1815 This function does not emit any diagnostics; the caller is responsible
1816 for that. */
1818 static tree
1820 {
1827 /* Convert in case a char is more than one unit. */
1831 }
1832 \f
1833 /* Return either DECL or its known constant value (if it has one). */
1835 tree
1837 {
1844 /* This is invalid if initial value is not constant.
1845 If it has either a function call, a memory reference,
1846 or a variable, then re-evaluating it could give different results. */
1848 /* Check for cases where this is sub-optimal, even though valid. */
1852 }
1854 /* Return either DECL or its known constant value (if it has one).
1855 Like the above, but always return decl outside of functions. */
1857 tree
1859 {
1860 /* Don't change a variable array bound or initial value to a constant
1861 in a place where a variable is invalid. */
1863 }
1865 /* Convert the array expression EXP to a pointer. */
1866 static tree
1868 {
1871 tree adr;
1873 tree ptrtype;
1886 /* In C++ array compound literals are temporary objects unless they are
1887 const or appear in namespace scope, so they are destroyed too soon
1888 to use them for much of anything (c++/53220). */
1890 {
1894 "converting an array compound literal to a pointer "
1896 }
1900 }
1902 /* Convert the function expression EXP to a pointer. */
1903 static tree
1905 {
1915 }
1917 /* Mark EXP as read, not just set, for set but not used -Wunused
1918 warning purposes. */
1920 void
1922 {
1924 {
1934 CASE_CONVERT:
1940 /* Pattern match what build_atomic_assign produces with modifycode
1941 NOP_EXPR. */
1945 {
1951 {
1959 {
1972 }
1974 {
1980 }
1981 }
1982 }
1983 /* FALLTHRU */
1989 }
1990 }
1992 /* Perform the default conversion of arrays and functions to pointers.
1993 Return the result of converting EXP. For any other expression, just
1994 return EXP.
1996 LOC is the location of the expression. */
1998 struct c_expr
2000 {
2006 {
2008 {
2015 {
2019 }
2025 {
2026 /* Before C99, non-lvalue arrays do not decay to pointers.
2027 Normally, using such an array would be invalid; but it can
2028 be used correctly inside sizeof or as a statement expression.
2029 Thus, do not give an error here; an error will result later. */
2031 }
2034 }
2041 }
2044 }
2046 struct c_expr
2048 {
2051 }
2053 /* Return whether EXPR should be treated as an atomic lvalue for the
2054 purposes of load and store handling. */
2056 static bool
2058 {
2066 /* Ignore _Atomic on register variables, since their addresses can't
2067 be taken so (a) atomicity is irrelevant and (b) the normal atomic
2068 sequences wouldn't work. Ignore _Atomic on structures containing
2069 bit-fields, since accessing elements of atomic structures or
2070 unions is undefined behavior (C11 6.5.2.3#5), but it's unclear if
2071 it's undefined at translation time or execution time, and the
2072 normal atomic sequences again wouldn't work. */
2074 {
2079 }
2083 }
2085 /* If EXPR is a named constant (C2x) derived from a constexpr variable
2086 - that is, a reference to such a variable, or a member extracted by
2087 a sequence of structure and union (but not array) member accesses
2088 (where union member accesses must access the same member as
2089 initialized) - then return the corresponding initializer;
2090 otherwise, return NULL_TREE. */
2092 static tree
2094 {
2122 {
2126 }
2130 /* Return a default initializer. */
2134 }
2136 /* Convert expression EXP (location LOC) from lvalue to rvalue,
2137 including converting functions and arrays to pointers if CONVERT_P.
2138 If READ_P, also mark the expression as having been read. If
2139 FOR_INIT, constexpr expressions of structure and union type should
2140 be replaced by the corresponding CONSTRUCTOR; otherwise, only
2141 constexpr scalars (including elements of structures and unions) are
2142 replaced by their initializers. */
2144 struct c_expr
2147 {
2156 {
2159 {
2160 /* A named constant of pointer type or type nullptr_t is not
2161 a null pointer constant even if the initializer is
2162 one. */
2168 }
2169 }
2171 {
2180 /* Expansion of a generic atomic load may require an addition
2181 element, so allocate enough to prevent a resize. */
2184 /* Remove the qualifiers for the rest of the expressions and
2185 create the VAL temp variable to hold the RHS. */
2190 /* Do not disable warnings for TMP even though it's artificial.
2191 -Winvalid-memory-model depends on it. */
2193 /* Issue __atomic_load (&expr, &tmp, SEQ_CST); */
2200 /* EXPR is always read. */
2203 /* Return tmp which contains the value loaded. */
2206 }
2209 exp.value = convert (build_qualified_type (TREE_TYPE (exp.value), TYPE_UNQUALIFIED), exp.value);
2213 }
2215 /* EXP is an expression of integer type. Apply the integer promotions
2216 to it and return the promoted value. */
2218 tree
2220 {
2226 /* Convert enums to the result of applying the integer promotions to
2227 their underlying type. */
2229 {
2232 {
2236 else
2238 }
2241 }
2243 /* ??? This should no longer be needed now bit-fields have their
2244 proper types. */
2247 {
2251 /* If it's thinner than an int, promote it like a
2252 c_promoting_integer_type_p, otherwise leave it alone. */
2256 }
2259 {
2260 /* Preserve unsignedness if not really getting any wider. */
2266 }
2269 }
2272 /* Perform default promotions for C data used in expressions.
2273 Enumeral types or short or char are converted to int.
2274 In addition, manifest constants symbols are replaced by their values. */
2276 tree
2278 {
2279 tree orig_exp;
2282 tree promoted_type;
2286 /* Functions and arrays have been converted during parsing. */
2291 /* Constants can be used directly unless they're not loadable. */
2295 /* Strip no-op conversions. */
2302 {
2306 }
2320 }
2321 \f
2322 /* Look up COMPONENT in a structure or union TYPE.
2324 If the component name is not found, returns NULL_TREE. Otherwise,
2325 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
2326 stepping down the chain to the component, which is in the last
2327 TREE_VALUE of the list. Normally the list is of length one, but if
2328 the component is embedded within (nested) anonymous structures or
2329 unions, the list steps down the chain to the component. */
2331 static tree
2333 {
2334 tree field;
2336 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
2337 to the field elements. Use a binary search on this array to quickly
2338 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
2339 will always be set for structures which have many elements.
2341 Duplicate field checking replaces duplicates with NULL_TREE so
2342 TYPE_LANG_SPECIFIC arrays are potentially no longer sorted. In that
2343 case just iterate using DECL_CHAIN. */
2347 {
2355 {
2360 {
2361 /* Step through all anon unions in linear fashion. */
2363 {
2366 {
2372 /* The Plan 9 compiler permits referring
2373 directly to an anonymous struct/union field
2374 using a typedef name. */
2382 }
2383 }
2385 /* Entire record is only anon unions. */
2389 /* Restart the binary search, with new lower bound. */
2391 }
2397 else
2399 }
2405 }
2406 else
2407 {
2409 {
2412 {
2418 /* The Plan 9 compiler permits referring directly to an
2419 anonymous struct/union field using a typedef
2420 name. */
2427 }
2431 }
2435 }
2438 }
2440 /* Recursively append candidate IDENTIFIER_NODEs to CANDIDATES. */
2442 static void
2445 {
2446 tree field;
2448 {
2452 candidates);
2456 }
2457 }
2459 /* Like "lookup_field", but find the closest matching IDENTIFIER_NODE,
2460 rather than returning a TREE_LIST for an exact match. */
2462 static tree
2464 {
2467 /* First, gather a list of candidates. */
2474 }
2476 /* Support function for build_component_ref's error-handling.
2478 Given DATUM_TYPE, and "DATUM.COMPONENT", where DATUM is *not* a
2479 struct or union, should we suggest "DATUM->COMPONENT" as a hint? */
2481 static bool
2483 {
2484 /* We don't do it for Objective-C, since Objective-C 2.0 dot-syntax
2485 allows "." for ptrs; we could be handling a failed attempt
2486 to access a property. */
2490 /* Only suggest it for pointers... */
2494 /* ...to structs/unions. */
2499 else
2501 }
2503 /* Make an expression to refer to the COMPONENT field of structure or
2504 union value DATUM. COMPONENT is an IDENTIFIER_NODE. LOC is the
2505 location of the COMPONENT_REF. COMPONENT_LOC is the location
2506 of COMPONENT. ARROW_LOC is the location of the first -> operand if
2507 it is from -> operator. */
2509 tree
2512 {
2516 tree ref;
2522 /* Detect Objective-C property syntax object.property. */
2527 /* See if there is a field or component with name COMPONENT. */
2530 {
2532 {
2535 }
2540 {
2543 {
2544 /* Attempt to provide a fixit replacement hint, if
2545 we have a valid range for the component. */
2546 location_t reported_loc
2554 }
2555 else
2558 }
2560 /* Accessing elements of atomic structures or unions is undefined
2561 behavior (C11 6.5.2.3#5). */
2563 {
2567 else
2570 }
2572 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
2573 This might be better solved in future the way the C++ front
2574 end does it - by giving the anonymous entities each a
2575 separate name and type, and then have build_component_ref
2576 recursively call itself. We can't do that here. */
2577 do
2578 {
2581 tree subtype;
2587 /* If this is an rvalue, it does not have qualifiers in C
2588 standard terms and we must avoid propagating such
2589 qualifiers down to a non-lvalue array that is then
2590 converted to a pointer. */
2591 use_datum_quals = (datum_lvalue
2600 NULL_TREE);
2617 }
2621 }
2623 {
2624 /* Special-case the error message for "ptr.field" for the case
2625 where the user has confused "." vs "->". */
2628 {
2632 "%qE is a pointer to pointer; did you mean to dereference "
2635 }
2636 else
2637 {
2638 /* "loc" should be the "." token. */
2642 datum);
2643 }
2645 }
2649 component);
2652 }
2653 \f
2654 /* Given an expression PTR for a pointer, return an expression
2655 for the value pointed to.
2656 ERRORSTRING is the name of the operator to appear in error messages.
2658 LOC is the location to use for the generated tree. */
2660 tree
2662 {
2665 tree ref;
2668 {
2671 {
2672 /* If a warning is issued, mark it to avoid duplicates from
2673 the backend. This only needs to be done at
2674 warn_strict_aliasing > 2. */
2679 }
2684 {
2688 }
2689 else
2690 {
2698 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2699 so that we get the proper error message if the result is used
2700 to assign to. Also, &* is supposed to be a no-op.
2701 And ANSI C seems to specify that the type of the result
2702 should be the const type. */
2703 /* A de-reference of a pointer to const is not a const. It is valid
2704 to change it via some other pointer. */
2711 }
2712 }
2717 }
2719 /* This handles expressions of the form "a[i]", which denotes
2720 an array reference.
2722 This is logically equivalent in C to *(a+i), but we may do it differently.
2723 If A is a variable or a member, we generate a primitive ARRAY_REF.
2724 This avoids forcing the array out of registers, and can work on
2725 arrays that are not lvalues (for example, members of structures returned
2726 by functions).
2728 For vector types, allow vector[i] but not i[vector], and create
2729 *(((type*)&vectortype) + i) for the expression.
2731 LOC is the location to use for the returned expression. */
2733 tree
2735 {
2736 tree ret;
2744 /* Allow vector[index] but not index[vector]. */
2746 {
2749 {
2754 }
2757 }
2760 {
2763 }
2766 {
2769 }
2771 /* ??? Existing practice has been to warn only when the char
2772 index is syntactically the index, not for char[array]. */
2776 /* Apply default promotions *after* noticing character types. */
2788 {
2791 /* An array that is indexed by a non-constant
2792 cannot be stored in a register; we must be able to do
2793 address arithmetic on its address.
2794 Likewise an array of elements of variable size. */
2798 {
2801 }
2802 /* An array that is indexed by a constant value which is not within
2803 the array bounds cannot be stored in a register either; because we
2804 would get a crash in store_bit_field/extract_bit_field when trying
2805 to access a non-existent part of the register. */
2809 {
2812 }
2816 {
2825 "ISO C90 forbids subscripting non-lvalue "
2827 }
2831 /* Array ref is const/volatile if the array elements are
2832 or if the array is. */
2841 /* This was added by rms on 16 Nov 91.
2842 It fixes vol struct foo *a; a->elts[1]
2843 in an inline function.
2844 Hope it doesn't break something else. */
2851 }
2852 else
2853 {
2864 RO_ARRAY_INDEXING);
2868 }
2869 }
2870 \f
2871 /* Build an external reference to identifier ID. FUN indicates
2872 whether this will be used for a function call. LOC is the source
2873 location of the identifier. This sets *TYPE to the type of the
2874 identifier, which is not the same as the type of the returned value
2875 for CONST_DECLs defined as enum constants. If the type of the
2876 identifier is not available, *TYPE is set to NULL. */
2877 tree
2879 {
2880 tree ref;
2883 /* In Objective-C, an instance variable (ivar) may be preferred to
2884 whatever lookup_name() found. */
2889 {
2894 decl);
2895 }
2897 /* Implicit function declaration. */
2900 /* Don't complain about something that's already been
2901 complained about. */
2903 else
2904 {
2907 }
2917 /* Recursive call does not count as usage. */
2919 {
2921 }
2924 {
2931 }
2934 {
2940 {
2945 }
2949 }
2954 {
2959 }
2960 /* C99 6.7.4p3: An inline definition of a function with external
2961 linkage ... shall not contain a reference to an identifier with
2962 internal linkage. */
2971 csi_internal);
2974 }
2976 /* Record details of decls possibly used inside sizeof or typeof. */
2977 struct maybe_used_decl
2978 {
2979 /* The decl. */
2980 tree decl;
2981 /* The level seen at (in_sizeof + in_typeof). */
2983 /* The next one at this level or above, or NULL. */
2985 };
2989 /* Record that DECL, an undefined static function reference seen
2990 inside sizeof or typeof, might be used if the operand of sizeof is
2991 a VLA type or the operand of typeof is a variably modified
2992 type. */
2994 static void
2996 {
3002 }
3004 /* Pop the stack of decls possibly used inside sizeof or typeof. If
3005 USED is false, just discard them. If it is true, mark them used
3006 (if no longer inside sizeof or typeof) or move them to the next
3007 level up (if still inside sizeof or typeof). */
3009 void
3011 {
3015 {
3017 {
3020 else
3022 }
3024 }
3027 }
3029 /* Return the result of sizeof applied to EXPR. */
3031 struct c_expr
3033 {
3036 {
3042 }
3043 else
3044 {
3049 {
3050 auto_diagnostic_group d;
3052 "%<sizeof%> on array function parameter %qE will "
3056 }
3066 {
3067 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */
3072 }
3074 }
3076 }
3078 /* Return the result of sizeof applied to T, a structure for the type
3079 name passed to sizeof (rather than the type itself). LOC is the
3080 location of the original expression. */
3082 struct c_expr
3084 {
3085 tree type;
3097 {
3100 }
3101 else
3104 {
3105 /* If the type is a [*] array, it is a VLA but is represented as
3106 having a size of zero. In such a case we must ensure that
3107 the result of sizeof does not get folded to a constant by
3108 c_fully_fold, because if the size is evaluated the result is
3109 not constant and so constraints on zero or negative size
3110 arrays must not be applied when this sizeof call is inside
3111 another array declarator. */
3117 }
3121 }
3123 /* Build a function call to function FUNCTION with parameters PARAMS.
3124 The function call is at LOC.
3125 PARAMS is a list--a chain of TREE_LIST nodes--in which the
3126 TREE_VALUE of each node is a parameter-expression.
3127 FUNCTION's data type may be a function type or a pointer-to-function. */
3129 tree
3131 {
3133 tree ret;
3141 }
3143 /* Give a note about the location of the declaration of DECL. */
3145 static void
3147 {
3151 }
3153 /* Build a function call to function FUNCTION with parameters PARAMS.
3154 If FUNCTION is the result of resolving an overloaded target built-in,
3155 ORIG_FUNDECL is the original function decl, otherwise it is null.
3156 ORIGTYPES, if not NULL, is a vector of types; each element is
3157 either NULL or the original type of the corresponding element in
3158 PARAMS. The original type may differ from TREE_TYPE of the
3159 parameter for enums. FUNCTION's data type may be a function type
3160 or pointer-to-function. This function changes the elements of
3161 PARAMS. */
3163 tree
3167 {
3170 tree tem;
3175 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3178 /* Convert anything with function type to a pointer-to-function. */
3180 {
3188 /* Atomic functions have type checking/casting already done. They are
3189 often rewritten and don't match the original parameter list. */
3192 }
3196 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
3197 expressions, like those used for ObjC messenger dispatches. */
3210 {
3214 function);
3216 {
3219 function);
3221 }
3222 else
3226 }
3231 /* fntype now gets the type of function pointed to. */
3235 /* Convert the parameters to the types declared in the
3236 function prototype, or apply default promotions. */
3243 /* Check that the function is called through a compatible prototype.
3244 If it is not, warn. */
3249 {
3250 /* This situation leads to run-time undefined behavior. We can't,
3251 therefore, simply error unless we can prove that all possible
3252 executions of the program must execute the code. */
3259 }
3263 /* Check that arguments to builtin functions match the expectations. */
3270 /* Check that the arguments to the function are valid. */
3279 {
3281 result
3284 else
3290 }
3291 else
3294 /* If -Wnonnull warning has been diagnosed, avoid diagnosing it again
3295 later. */
3299 /* In this improbable scenario, a nested function returns a VM type.
3300 Create a TARGET_EXPR so that the call always has a LHS, much as
3301 what the C++ FE does for functions returning non-PODs. */
3303 {
3307 }
3310 {
3315 }
3317 }
3319 /* Like build_function_call_vec, but call also resolve_overloaded_builtin. */
3321 tree
3325 {
3326 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3329 /* Convert anything with function type to a pointer-to-function. */
3331 {
3332 /* Implement type-directed function overloading for builtins.
3333 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
3334 handle all the type checking. The result is a complete expression
3335 that implements this function call. */
3339 }
3341 }
3342 \f
3343 /* Helper for convert_arguments called to convert the VALue of argument
3344 number ARGNUM from ORIGTYPE to the corresponding parameter number
3345 PARMNUM and TYPE.
3346 PLOC is the location where the conversion is being performed.
3347 FUNCTION and FUNDECL are the same as in convert_arguments.
3348 VALTYPE is the original type of VAL before the conversion and,
3349 for EXCESS_PRECISION_EXPR, the operand of the expression.
3350 NPC is true if VAL represents the null pointer constant (VAL itself
3351 will have been folded to an integer constant).
3352 RNAME is the same as FUNCTION except in Objective C when it's
3353 the function selector.
3354 EXCESS_PRECISION is true when VAL was originally represented
3355 as EXCESS_PRECISION_EXPR.
3356 WARNOPT is the same as in convert_for_assignment. */
3358 static tree
3363 {
3364 /* Formal parm type is specified by a function prototype. */
3367 {
3371 }
3373 /* Optionally warn about conversions that differ from the default
3374 conversions. */
3376 {
3380 "passing argument %d of %qE as integer rather "
3386 "passing argument %d of %qE as integer rather "
3392 "passing argument %d of %qE as complex rather "
3398 "passing argument %d of %qE as floating rather "
3404 "passing argument %d of %qE as complex rather "
3410 "passing argument %d of %qE as floating rather "
3413 /* ??? At some point, messages should be written about
3414 conversions between complex types, but that's too messy
3415 to do now. */
3418 {
3421 /* Warn if any argument is passed as `float',
3422 since without a prototype it would be `double'. */
3426 "passing argument %d of %qE as %<float%> "
3430 /* Warn if mismatch between argument and prototype
3431 for decimal float types. Warn of conversions with
3432 binary float types and of precision narrowing due to
3433 prototype. */
3441 && (formal_prec
3444 && (valtype
3445 != dfloat64_type_node
3446 && (valtype
3449 && (valtype
3452 "passing argument %d of %qE as %qT "
3456 }
3457 /* Detect integer changing in width or signedness.
3458 These warnings are only activated with
3459 -Wtraditional-conversion, not with -Wtraditional. */
3463 {
3473 /* No warning if function asks for enum
3474 and the actual arg is that enum type. */
3475 ;
3478 "passing argument %d of %qE "
3482 ;
3483 /* Don't complain if the formal parameter type
3484 is an enum, because we can't tell now whether
3485 the value was an enum--even the same enum. */
3487 ;
3490 /* Change in signedness doesn't matter
3491 if a constant value is unaffected. */
3492 ;
3493 /* If the value is extended from a narrower
3494 unsigned type, it doesn't matter whether we
3495 pass it as signed or unsigned; the value
3496 certainly is the same either way. */
3499 ;
3502 "passing argument %d of %qE "
3505 else
3507 "passing argument %d of %qE "
3510 }
3511 }
3513 /* Possibly restore an EXCESS_PRECISION_EXPR for the
3514 sake of better warnings from convert_and_check. */
3529 }
3531 /* Convert the argument expressions in the vector VALUES
3532 to the types in the list TYPELIST.
3534 If TYPELIST is exhausted, or when an element has NULL as its type,
3535 perform the default conversions.
3537 ORIGTYPES is the original types of the expressions in VALUES. This
3538 holds the type of enum values which have been converted to integral
3539 types. It may be NULL.
3541 FUNCTION is a tree for the called function. It is used only for
3542 error messages, where it is formatted with %qE.
3544 This is also where warnings about wrong number of args are generated.
3546 ARG_LOC are locations of function arguments (if any).
3548 Returns the actual number of arguments processed (which may be less
3549 than the length of VALUES in some error situations), or -1 on
3550 failure. */
3552 static int
3556 {
3563 tree selector;
3565 /* Change pointer to function to the function itself for
3566 diagnostics. */
3571 /* Handle an ObjC selector specially for diagnostics. */
3574 /* For a call to a built-in function declared without a prototype,
3575 set to the built-in function's argument list. */
3578 /* For type-generic built-in functions, determine whether excess
3579 precision should be removed (classification) or not
3580 (comparison). */
3583 {
3586 {
3587 /* For a call to a built-in function declared without a prototype
3588 use the types of the parameters of the internal built-in to
3589 match those of the arguments to. */
3592 }
3594 /* For type-generic built-in functions, determine whether excess
3595 precision should be removed (classification) or not
3596 (comparison). */
3599 {
3613 /* The last argument of these type-generic builtins
3614 should not be promoted. */
3620 }
3621 }
3623 /* Scan the given expressions (VALUES) and types (TYPELIST), producing
3624 individual converted arguments. */
3632 {
3633 /* The type of the function parameter (if it was declared with one). */
3635 /* The type of the built-in function parameter (if the function
3636 is a built-in). Used to detect type incompatibilities in
3637 calls to built-ins declared without a prototype. */
3638 tree builtin_type = (builtin_typetail
3640 /* The original type of the argument being passed to the function. */
3642 /* The called function (or function selector in Objective C). */
3646 /* Set for EXCESS_PRECISION_EXPR arguments. */
3648 /* The value of the argument after conversion to the type
3649 of the function parameter it is passed to. */
3650 tree parmval;
3651 /* Some __atomic_* builtins have additional hidden argument at
3652 position 0. */
3653 location_t ploc
3659 {
3662 else
3666 }
3669 {
3671 "too many arguments to built-in function %qE "
3675 }
3678 {
3681 }
3683 /* Determine if VAL is a null pointer constant before folding it. */
3686 /* If there is excess precision and a prototype, convert once to
3687 the required type rather than converting via the semantic
3688 type. Likewise without a prototype a float value represented
3689 as long double should be converted once to double. But for
3690 type-generic classification functions excess precision must
3691 be removed here. */
3694 {
3697 }
3703 /* Some floating-point arguments must be promoted to double when
3704 no type is specified by a prototype. This applies to
3705 arguments of type float, and to architecture-specific types
3706 (ARM __fp16), but not to _FloatN or _FloatNx types. */
3715 {
3716 /* Promote this argument, unless it has a _FloatN or
3717 _FloatNx type. */
3721 {
3724 }
3725 /* Don't promote __bf16 either. */
3728 }
3731 {
3736 }
3738 {
3741 else
3742 {
3743 /* Convert `float' to `double'. */
3746 "implicit conversion from %qT to %qT when passing "
3750 }
3751 }
3754 /* A "double" argument with excess precision being passed
3755 without a prototype or in variable arguments.
3756 The last argument of __builtin_*_overflow_p should not be
3757 promoted. */
3761 {
3764 }
3766 {
3768 }
3769 else
3770 /* Convert `short' and `char' to full-size `int'. */
3778 {
3779 /* For a call to a built-in function declared without a prototype,
3780 perform the conversions from the argument to the expected type
3781 but issue warnings rather than errors for any mismatches.
3782 Ignore the converted argument and use the PARMVAL obtained
3783 above by applying default conversions instead. */
3787 excess_precision,
3788 OPT_Wbuiltin_declaration_mismatch);
3789 }
3796 }
3801 {
3805 }
3808 {
3814 "too few arguments to built-in function %qE "
3817 }
3820 }
3821 \f
3822 /* This is the entry point used by the parser to build unary operators
3823 in the input. CODE, a tree_code, specifies the unary operator, and
3824 ARG is the operand. For unary plus, the C parser currently uses
3825 CONVERT_EXPR for code.
3827 LOC is the location to use for the tree generated.
3828 */
3830 struct c_expr
3832 {
3840 {
3842 }
3843 else
3844 {
3849 }
3851 /* We are typically called when parsing a prefix token at LOC acting on
3852 ARG. Reflect this by updating the source range of the result to
3853 start at LOC and end at the end of ARG. */
3858 }
3860 /* Returns true if TYPE is a character type, *not* including wchar_t. */
3862 bool
3864 {
3870 }
3872 /* This is the entry point used by the parser to build binary operators
3873 in the input. CODE, a tree_code, specifies the binary operator, and
3874 ARG1 and ARG2 are the operands. In addition to constructing the
3875 expression, we check for operands that were written with other binary
3876 operators in a way that is likely to confuse the user.
3878 LOCATION is the location of the binary operator. */
3880 struct c_expr
3883 {
3903 {
3908 }
3917 /* Check for cases such as x+y<<z which users are likely
3918 to misinterpret. */
3928 {
3932 {
3936 else
3938 }
3940 {
3944 else
3946 }
3949 }
3955 /* Avoid warning for !!x == y. */
3958 {
3959 /* Avoid warning for !b == y where b has _Bool type. */
3964 {
3966 do
3967 {
3974 else
3976 }
3978 }
3981 }
3983 /* Warn about comparisons against string literals, with the exception
3984 of testing for equality or inequality of a string literal with NULL. */
3986 {
3993 /* Warn for ptr == '\0', it's likely that it should've been ptr[0]. */
3997 {
3998 auto_diagnostic_group d;
4000 "comparison between pointer and zero character "
4004 }
4008 {
4009 auto_diagnostic_group d;
4011 "comparison between pointer and zero character "
4015 }
4016 }
4020 "comparison with string literal results in unspecified "
4034 /* Warn about comparisons of different enum types. */
4049 location,
4053 }
4054 \f
4055 /* Return a tree for the difference of pointers OP0 and OP1.
4056 The resulting tree has type ptrdiff_t. If POINTER_SUBTRACT sanitization is
4057 enabled, assign to INSTRUMENT_EXPR call to libsanitizer. */
4059 static tree
4061 {
4071 /* If the operands point into different address spaces, we need to
4072 explicitly convert them to pointers into the common address space
4073 before we can subtract the numerical address values. */
4075 {
4076 addr_space_t as_common;
4077 tree common_type;
4079 /* Determine the common superset address space. This is guaranteed
4080 to exist because the caller verified that comp_target_types
4081 returned non-zero. */
4088 }
4090 /* Determine integer type result of the subtraction. This will usually
4091 be the same as the result type (ptrdiff_t), but may need to be a wider
4092 type if pointers for the address space are wider than ptrdiff_t. */
4095 else
4107 {
4113 }
4115 /* First do the subtraction, then build the divide operator
4116 and only convert at the very end.
4117 Do not do default conversions in case restype is a short type. */
4119 /* POINTER_DIFF_EXPR requires a signed integer type of the same size as
4120 pointers. If some platform cannot provide that, or has a larger
4121 ptrdiff_type to support differences larger than half the address
4122 space, cast the pointers to some larger integer type and do the
4123 computations in that type. */
4127 else
4128 {
4129 /* Cast away qualifiers. */
4133 }
4135 /* This generates an error if op1 is pointer to incomplete type. */
4148 /* Divide by the size, in easiest possible way. */
4152 /* Convert to final result type if necessary. */
4154 }
4155 \f
4156 /* Expand atomic compound assignments into an appropriate sequence as
4157 specified by the C11 standard section 6.5.16.2.
4159 _Atomic T1 E1
4160 T2 E2
4161 E1 op= E2
4163 This sequence is used for all types for which these operations are
4164 supported.
4166 In addition, built-in versions of the 'fe' prefixed routines may
4167 need to be invoked for floating point (real, complex or vector) when
4168 floating-point exceptions are supported. See 6.5.16.2 footnote 113.
4170 T1 newval;
4171 T1 old;
4172 T1 *addr
4173 T2 val
4174 fenv_t fenv
4176 addr = &E1;
4177 val = (E2);
4178 __atomic_load (addr, &old, SEQ_CST);
4179 feholdexcept (&fenv);
4180 loop:
4181 newval = old op val;
4182 if (__atomic_compare_exchange_strong (addr, &old, &newval, SEQ_CST,
4183 SEQ_CST))
4184 goto done;
4185 feclearexcept (FE_ALL_EXCEPT);
4186 goto loop:
4187 done:
4188 feupdateenv (&fenv);
4190 The compiler will issue the __atomic_fetch_* built-in when possible,
4191 otherwise it will generate the generic form of the atomic operations.
4192 This requires temp(s) and has their address taken. The atomic processing
4193 is smart enough to figure out when the size of an object can utilize
4194 a lock-free version, and convert the built-in call to the appropriate
4195 lock-free routine. The optimizers will then dispose of any temps that
4196 are no longer required, and lock-free implementations are utilized as
4197 long as there is target support for the required size.
4199 If the operator is NOP_EXPR, then this is a simple assignment, and
4200 an __atomic_store is issued to perform the assignment rather than
4201 the above loop. */
4203 /* Build an atomic assignment at LOC, expanding into the proper
4204 sequence to store LHS MODIFYCODE= RHS. Return a value representing
4205 the result of the operation, unless RETURN_OLD_P, in which case
4206 return the old value of LHS (this is only for postincrement and
4207 postdecrement). */
4209 static tree
4212 {
4225 tree nonatomic_rhs_semantic_type;
4226 tree rhs_type;
4233 /* Allocate enough vector items for a compare_exchange. */
4236 /* Create a compound statement to hold the sequence of statements
4237 with a loop. */
4239 {
4242 /* For consistency with build_modify_expr on non-_Atomic,
4243 mark the lhs as read. Also, it would be very hard to match
4244 such expressions in mark_exp_read. */
4246 }
4248 /* Remove any excess precision (which is only present here in the
4249 case of compound assignments). */
4251 {
4254 }
4257 /* Fold the RHS if it hasn't already been folded. */
4261 /* Remove the qualifiers for the rest of the expressions and create
4262 the VAL temp variable to hold the RHS. */
4266 TYPE_UNQUALIFIED);
4271 NULL_TREE);
4277 /* NOP_EXPR indicates it's a straight store of the RHS. Simply issue
4278 an atomic_store. */
4280 {
4282 /* Build __atomic_store (&lhs, &val, SEQ_CST) */
4293 /* VAL is the value which was stored, return a COMPOUND_STMT of
4294 the statement and that value. */
4296 }
4298 /* Attempt to implement the atomic operation as an __atomic_fetch_* or
4299 __atomic_*_fetch built-in rather than a CAS loop. atomic_bool type
4300 isn't applicable for such builtins. ??? Do we want to handle enums? */
4303 {
4304 built_in_function fncode;
4306 {
4309 fncode = (return_old_p
4310 ? BUILT_IN_ATOMIC_FETCH_ADD_N
4314 fncode = (return_old_p
4315 ? BUILT_IN_ATOMIC_FETCH_SUB_N
4319 fncode = (return_old_p
4320 ? BUILT_IN_ATOMIC_FETCH_AND_N
4324 fncode = (return_old_p
4325 ? BUILT_IN_ATOMIC_FETCH_OR_N
4329 fncode = (return_old_p
4330 ? BUILT_IN_ATOMIC_FETCH_XOR_N
4335 }
4337 /* We can only use "_1" through "_16" variants of the atomic fetch
4338 built-ins. */
4343 /* If this is a pointer type, we need to multiply by the size of
4344 the pointer target type. */
4346 {
4348 /* ??? This would introduce -Wdiscarded-qualifiers
4349 warning: __atomic_fetch_* expect volatile void *
4350 type as the first argument. (Assignments between
4351 atomic and non-atomic objects are OK.) */
4358 }
4360 /* Build __atomic_fetch_* (&lhs, &val, SEQ_CST), or
4361 __atomic_*_fetch (&lhs, &val, SEQ_CST). */
4376 /* Finish the compound statement. */
4379 /* NEWVAL is the value which was stored, return a COMPOUND_STMT of
4380 the statement and that value. */
4382 }
4384 cas_loop:
4385 /* Create the variables and labels required for the op= form. */
4402 /* __atomic_load (addr, &old, SEQ_CST). */
4409 NULL_TREE);
4413 /* Create the expressions for floating-point environment
4414 manipulation, if required. */
4424 /* loop: */
4427 /* newval = old + val; */
4432 {
4436 }
4437 else
4443 {
4445 NULL_TREE);
4448 }
4450 /* if (__atomic_compare_exchange (addr, &old, &new, false, SEQ_CST, SEQ_CST))
4451 goto done; */
4471 /* goto loop; */
4476 /* done: */
4482 /* Finish the compound statement. */
4485 /* NEWVAL is the value that was successfully stored, return a
4486 COMPOUND_EXPR of the statement and the appropriate value. */
4489 }
4491 /* Construct and perhaps optimize a tree representation
4492 for a unary operation. CODE, a tree_code, specifies the operation
4493 and XARG is the operand.
4494 For any CODE other than ADDR_EXPR, NOCONVERT suppresses the default
4495 promotions (such as from short to int).
4496 For ADDR_EXPR, the default promotions are not applied; NOCONVERT allows
4497 non-lvalues; this is only used to handle conversion of non-lvalue arrays
4498 to pointers in C99.
4500 LOCATION is the location of the operator. */
4502 tree
4505 {
4506 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
4510 tree val;
4531 {
4534 }
4537 {
4540 }
4543 {
4545 /* This is used for unary plus, because a CONVERT_EXPR
4546 is enough to prevent anybody from looking inside for
4547 associativity, but won't generate any code. */
4552 {
4555 }
4566 {
4569 }
4575 /* ~ works on integer types and non float vectors. */
4580 {
4583 /* Warn if the expression has boolean value. */
4589 {
4590 auto_diagnostic_group d;
4593 {
4597 }
4598 }
4601 }
4603 {
4609 }
4610 else
4611 {
4614 }
4619 {
4622 }
4629 {
4632 }
4638 /* Conjugating a real value is a no-op, but allow it anyway. */
4641 {
4644 }
4654 {
4658 }
4660 {
4663 }
4664 else
4667 /* If the TRUTH_NOT_EXPR has been folded, reset the location. */
4687 {
4690 noconvert);
4698 }
4700 /* Complain about anything that is not a true lvalue. In
4701 Objective-C, skip this check for property_refs. */
4706 ? lv_increment
4711 {
4715 else
4718 }
4721 {
4725 else
4728 }
4730 /* Ensure the argument is fully folded inside any SAVE_EXPR. */
4736 /* Increment or decrement the real part of the value,
4737 and don't change the imaginary part. */
4739 {
4746 {
4758 }
4759 }
4761 /* Report invalid types. */
4767 {
4770 else
4774 }
4776 {
4777 tree inc;
4781 /* Compute the increment. */
4784 {
4785 /* If pointer target is an incomplete type,
4786 we just cannot know how to do the arithmetic. */
4788 {
4793 else
4797 }
4800 {
4804 else
4807 }
4808 else
4814 }
4816 {
4817 /* For signed fract types, we invert ++ to -- or
4818 -- to ++, and change inc from 1 to -1, because
4819 it is not possible to represent 1 in signed fract constants.
4820 For unsigned fract types, the result always overflows and
4821 we get an undefined (original) or the maximum value. */
4833 }
4834 else
4835 {
4840 }
4842 /* If 'arg' is an Objective-C PROPERTY_REF expression, then we
4843 need to ask Objective-C to build the increment or decrement
4844 expression for it. */
4849 /* Report a read-only lvalue. */
4851 {
4857 }
4864 /* If the argument is atomic, use the special code sequences for
4865 atomic compound assignment. */
4867 {
4872 ? PLUS_EXPR
4875 ? inc
4880 }
4884 else
4889 TYPE_UNQUALIFIED);
4892 }
4895 /* Note that this operation never does default_conversion. */
4897 /* The operand of unary '&' must be an lvalue (which excludes
4898 expressions of type void), or, in C99, the result of a [] or
4899 unary '*' operator. */
4905 /* Let &* cancel out to simplify resulting code. */
4907 {
4908 /* Don't let this be an lvalue. */
4913 }
4915 /* Anything not already handled and not a true memory reference
4916 or a non-lvalue array is an error. */
4921 /* Move address operations inside C_MAYBE_CONST_EXPR to simplify
4922 folding later. */
4924 {
4927 noconvert);
4934 }
4936 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
4939 /* If the lvalue is const or volatile, merge that into the type
4940 to which the address will point. This is only needed
4941 for function types. */
4945 {
4955 }
4958 {
4961 {
4965 }
4967 /* fall through */
4971 {
4975 {
4979 }
4984 "address of array with reverse scalar storage "
4986 }
4990 }
5000 /* ??? Cope with user tricks that amount to offsetof. Delete this
5001 when we have proper support for integer constant expressions. */
5005 {
5008 }
5021 }
5026 ret = (require_constant_value
5029 else
5031 return_build_unary_op:
5042 }
5044 /* Return nonzero if REF is an lvalue valid for this language.
5045 Lvalues can be assigned, unless their type has TYPE_READONLY.
5046 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
5048 bool
5050 {
5054 {
5069 /* MEM_REFs can appear from -fgimple parsing or folding, so allow them
5070 here as well. */
5085 }
5086 }
5087 \f
5088 /* Give a warning for storing in something that is read-only in GCC
5089 terms but not const in ISO C terms. */
5091 static void
5093 {
5095 {
5107 }
5109 }
5112 /* Return nonzero if REF is an lvalue valid for this language;
5113 otherwise, print an error message and return zero. USE says
5114 how the lvalue is being used and so selects the error message.
5115 LOCATION is the location at which any error should be reported. */
5117 static int
5119 {
5126 }
5127 \f
5128 /* Mark EXP saying that we need to be able to take the
5129 address of it; it should not be allocated in a register.
5130 Returns true if successful. ARRAY_REF_P is true if this
5131 is for ARRAY_REF construction - in that case we don't want
5132 to look through VIEW_CONVERT_EXPR from VECTOR_TYPE to ARRAY_TYPE,
5133 it is fine to use ARRAY_REFs for vector subscripts on vector
5134 register variables. */
5136 bool
5138 {
5143 {
5154 {
5158 }
5159 /* FALLTHRU */
5169 {
5172 }
5187 {
5189 {
5190 error
5193 }
5195 }
5197 {
5200 else
5203 }
5205 /* FALLTHRU */
5208 /* FALLTHRU */
5211 }
5212 }
5213 \f
5214 /* Convert EXPR to TYPE, warning about conversion problems with
5215 constants. SEMANTIC_TYPE is the type this conversion would use
5216 without excess precision. If SEMANTIC_TYPE is NULL, this function
5217 is equivalent to convert_and_check. This function is a wrapper that
5218 handles conversions that may be different than
5219 the usual ones because of excess precision. */
5221 static tree
5223 tree semantic_type)
5224 {
5228 /* For C11, integer conversions may have results with excess
5229 precision. */
5235 {
5236 /* For integers, we need to check the real conversion, not
5237 the conversion to the excess precision type. */
5239 }
5240 /* Result type is the excess precision type, which should be
5241 large enough, so do not check. */
5243 }
5245 /* If EXPR refers to a built-in declared without a prototype returns
5246 the actual type of the built-in and, if non-null, set *BLTIN to
5247 a pointer to the built-in. Otherwise return the type of EXPR
5248 and clear *BLTIN if non-null. */
5250 static tree
5252 {
5253 tree dummy;
5277 }
5279 /* Build and return a conditional expression IFEXP ? OP1 : OP2. If
5280 IFEXP_BCP then the condition is a call to __builtin_constant_p, and
5281 if folded to an integer constant then the unselected half may
5282 contain arbitrary operations not normally permitted in constant
5283 expressions. Set the location of the expression to LOC. */
5285 tree
5289 {
5290 tree type1;
5291 tree type2;
5299 tree ret;
5311 /* Promote both alternatives. */
5336 /* C90 does not permit non-lvalue arrays in conditional expressions.
5337 In C99 they will be pointers by now. */
5339 {
5342 }
5350 {
5353 {
5357 }
5359 {
5363 }
5364 }
5367 {
5378 }
5380 /* Quickly detect the usual case where op1 and op2 have the same type
5381 after promotion. */
5383 {
5386 else
5388 }
5393 {
5394 /* In C11, a conditional expression between a floating-point
5395 type and an integer type should convert the integer type to
5396 the evaluation format of the floating-point type, with
5397 possible excess precision. */
5401 {
5402 tree eptype;
5405 {
5409 }
5412 {
5416 }
5417 }
5422 "implicit conversion from %qT to %qT to "
5424 colon_loc);
5426 /* If -Wsign-compare, warn here if type1 and type2 have
5427 different signedness. We'll promote the signed to unsigned
5428 and later code won't know it used to be different.
5429 Do this check on the original types, so that explicit casts
5430 will be considered, but default promotions won't. */
5432 {
5437 {
5440 /* Do not warn if the result type is signed, since the
5441 signed type will only be chosen if it can represent
5442 all the values of the unsigned type. */
5445 else
5446 {
5450 /* Do not warn if the signed quantity is an
5451 unsuffixed integer literal (or some static
5452 constant expression involving such literals) and
5453 it is non-negative. This warning requires the
5454 operands to be folded for best results, so do
5455 that folding in this case even without
5456 warn_sign_compare to avoid warning options
5457 possibly affecting code generation. */
5458 c_inhibit_evaluation_warnings
5462 c_inhibit_evaluation_warnings
5465 c_inhibit_evaluation_warnings
5469 c_inhibit_evaluation_warnings
5473 {
5476 || (unsigned_op1
5481 "operand of %<?:%> changes signedness from "
5482 "%qT to %qT due to unsignedness of other "
5485 else
5487 "operand of %<?:%> changes signedness from "
5488 "%qT to %qT due to unsignedness of other "
5491 }
5496 }
5497 }
5498 }
5499 }
5501 {
5506 }
5508 {
5511 addr_space_t as_common;
5520 {
5524 }
5529 {
5534 {
5535 /* roles are swapped */
5538 }
5542 {
5545 "pointer to array loses qualifier "
5549 "pointer to array loses qualifier "
5551 }
5554 "ISO C forbids conditional expr between "
5556 /* for array, use qualifiers of element type */
5560 }
5561 /* Objective-C pointer comparisons are a bit more lenient. */
5564 else
5565 {
5569 "pointer type mismatch "
5571 {
5574 }
5575 result_type = build_pointer_type
5577 }
5578 }
5581 {
5585 else
5586 {
5588 }
5590 }
5593 {
5597 else
5598 {
5600 }
5602 }
5603 /* 6.5.15: "if one is a null pointer constant (other than a pointer) or has
5604 type nullptr_t and the other is a pointer, the result type is the pointer
5605 type." */
5612 {
5615 else
5616 {
5619 }
5620 }
5622 /* Merge const and volatile flags of the incoming types. */
5623 result_type
5629 semantic_result_type);
5631 semantic_result_type);
5634 {
5637 }
5639 {
5642 }
5644 && op1_int_operands
5647 {
5654 }
5656 /* Need to convert condition operand into a vector mask. */
5658 {
5665 }
5669 else
5670 {
5672 {
5673 /* Use c_fully_fold here, since C_MAYBE_CONST_EXPR might be
5674 nested inside of the expression. */
5677 }
5681 }
5687 /* If the OP1 and OP2 are the same and don't have side-effects,
5688 warn here, because the COND_EXPR will be turned into OP1. */
5696 }
5697 \f
5698 /* EXPR is an expression, location LOC, whose result is discarded.
5699 Warn if it is a call to a nodiscard function (or a COMPOUND_EXPR
5700 whose right-hand operand is such a call, possibly recursively). */
5702 static void
5704 {
5708 {
5712 }
5718 tree attr;
5723 {
5728 auto_diagnostic_group d;
5732 "ignoring return value of %qD, declared with "
5734 else
5736 "ignoring return value of %qD, declared with "
5740 }
5741 else
5742 {
5750 auto_diagnostic_group d;
5754 "ignoring return value of type %qT, declared "
5757 else
5759 "ignoring return value of type %qT, declared "
5762 {
5764 {
5769 }
5770 }
5771 }
5772 }
5774 /* Return a compound expression that performs two expressions and
5775 returns the value of the second of them.
5777 LOC is the location of the COMPOUND_EXPR. */
5779 tree
5781 {
5784 tree ret;
5796 {
5799 }
5802 {
5803 /* The left-hand operand of a comma expression is like an expression
5804 statement: with -Wunused, we should warn if it doesn't have
5805 any side-effects, unless it was explicitly cast to (void). */
5807 {
5815 else
5818 }
5819 }
5822 {
5826 {
5830 }
5836 }
5838 /* With -Wunused, we should also warn if the left-hand operand does have
5839 side-effects, but computes a value which is not used. For example, in
5840 `foo() + bar(), baz()' the result of the `+' operator is not used,
5841 so we should issue a warning. */
5853 && expr1_int_operands
5862 }
5864 /* Issue -Wcast-qual warnings when appropriate. TYPE is the type to
5865 which we are casting. OTYPE is the type of the expression being
5866 cast. Both TYPE and OTYPE are pointer types. LOC is the location
5867 of the cast. -Wcast-qual appeared on the command line. Named
5868 address space qualifiers are not handled here, because they result
5869 in different warnings. */
5871 static void
5873 {
5880 /* Check that the qualifiers on IN_TYPE are a superset of the
5881 qualifiers of IN_OTYPE. The outermost level of POINTER_TYPE
5882 nodes is uninteresting and we stop as soon as we hit a
5883 non-POINTER_TYPE node on either type. */
5884 do
5885 {
5889 /* GNU C allows cv-qualified function types. 'const' means the
5890 function is very pure, 'volatile' means it can't return. We
5891 need to warn when such qualifiers are added, not when they're
5892 taken away. */
5897 else
5900 }
5909 /* There are qualifiers present in IN_OTYPE that are not present
5910 in IN_TYPE. */
5913 discarded);
5918 /* A cast from **T to const **T is unsafe, because it can cause a
5919 const value to be changed with no additional warning. We only
5920 issue this warning if T is the same on both sides, and we only
5921 issue the warning if there are the same number of pointers on
5922 both sides, as otherwise the cast is clearly unsafe anyhow. A
5923 cast is unsafe when a qualifier is added at one level and const
5924 is not present at all outer levels.
5926 To issue this warning, we check at each level whether the cast
5927 adds new qualifiers not already seen. We don't need to special
5928 case function types, as they won't have the same
5929 TYPE_MAIN_VARIANT. */
5939 do
5940 {
5945 {
5947 "to be safe all intermediate pointers in cast from "
5951 }
5954 }
5956 }
5958 /* Heuristic check if two parameter types can be considered ABI-equivalent. */
5960 static bool
5962 {
5973 /* The signedness of the parameter matters only when an integral
5974 type smaller than int is promoted to int, otherwise only the
5975 precision of the parameter matters.
5976 This check should make sure that the callee does not see
5977 undefined values in argument registers. */
5987 }
5989 /* Check if a type cast between two function types can be considered safe. */
5991 static bool
5993 {
6012 }
6014 /* Build an expression representing a cast to type TYPE of expression EXPR.
6015 LOC is the location of the cast-- typically the open paren of the cast. */
6017 tree
6019 {
6020 tree value;
6034 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
6035 only in <protocol> qualifications. But when constructing cast expressions,
6036 the protocols do matter and must be kept around. */
6043 {
6046 }
6049 {
6052 }
6055 {
6059 }
6062 {
6066 ;
6071 /* Convert to remove any qualifiers from VALUE's type. */
6073 }
6075 {
6076 tree field;
6085 {
6086 tree t;
6098 }
6101 }
6102 else
6103 {
6107 {
6111 }
6115 /* Optionally warn about potentially worrisome casts. */
6121 /* Warn about conversions between pointers to disjoint
6122 address spaces. */
6126 {
6129 addr_space_t as_common;
6132 {
6143 else
6148 }
6149 }
6151 /* Warn about possible alignment problems. */
6157 /* Don't warn about opaque types, where the actual alignment
6158 restriction is unknown. */
6170 /* Unlike conversion of integers to pointers, where the
6171 warning is disabled for converting constants because
6172 of cases such as SIG_*, warn about converting constant
6173 pointers to integers. In some cases it may cause unwanted
6174 sign extension, and a warning is appropriate. */
6181 "cast from function call of type %qT "
6188 /* Don't warn about converting any constant. */
6197 /* If pedantic, warn for conversions between function and object
6198 pointer types, except for converting a null pointer constant
6199 to function pointer type. */
6224 "cast between incompatible function types"
6230 /* Ignore any integer overflow caused by the cast. */
6232 {
6234 {
6236 {
6237 /* Avoid clobbering a shared constant. */
6240 }
6241 }
6243 /* Reset VALUE's overflow flags, ensuring constant sharing. */
6245 }
6246 }
6248 /* Don't let a cast be an lvalue. */
6252 /* Don't allow the results of casting to floating-point or complex
6253 types be confused with actual constants, or casts involving
6254 integer and pointer types other than direct integer-to-integer
6255 and integer-to-pointer be confused with integer constant
6256 expressions and null pointer constants. */
6266 /* If the expression has integer operands and so can occur in an
6267 unevaluated part of an integer constant expression, ensure the
6268 return value reflects this. */
6277 }
6279 /* Interpret a cast of expression EXPR to type TYPE. LOC is the
6280 location of the open paren of the cast, or the position of the cast
6281 expr. */
6282 tree
6284 {
6285 tree type;
6288 tree ret;
6291 /* This avoids warnings about unprototyped casts on
6292 integers. E.g. "#define SIG_DFL (void(*)())0". */
6304 {
6311 }
6316 /* C++ does not permits types to be defined in a cast, but it
6317 allows references to incomplete types. */
6323 }
6324 \f
6325 /* Build an assignment expression of lvalue LHS from value RHS.
6326 If LHS_ORIGTYPE is not NULL, it is the original type of LHS, which
6327 may differ from TREE_TYPE (LHS) for an enum bitfield.
6328 MODIFYCODE is the code for a binary operator that we use
6329 to combine the old value of LHS with RHS to get the new value.
6330 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
6331 If RHS_ORIGTYPE is not NULL_TREE, it is the original type of RHS,
6332 which may differ from TREE_TYPE (RHS) for an enum value.
6334 LOCATION is the location of the MODIFYCODE operator.
6335 RHS_LOC is the location of the RHS. */
6337 tree
6341 {
6342 tree result;
6343 tree newrhs;
6350 /* Types that aren't fully specified cannot be used in assignments. */
6353 /* Avoid duplicate error messages from operands that had errors. */
6357 /* Ensure an error for assigning a non-lvalue array to an array in
6358 C90. */
6360 {
6363 }
6365 /* For ObjC properties, defer this check. */
6374 {
6377 rhs_origtype);
6386 }
6388 /* If a binary op has been requested, combine the old LHS value with the RHS
6389 producing the value we should actually store into the LHS. */
6392 {
6396 /* Construct the RHS for any non-atomic compound assignemnt. */
6398 {
6399 /* If in LHS op= RHS the RHS has side-effects, ensure they
6400 are preevaluated before the rest of the assignment expression's
6401 side-effects, because RHS could contain e.g. function calls
6402 that modify LHS. */
6404 {
6407 else
6412 newrhs);
6413 }
6417 /* The original type of the right hand side is no longer
6418 meaningful. */
6420 }
6421 }
6424 {
6425 /* Check if we are modifying an Objective-C property reference;
6426 if so, we need to generate setter calls. */
6429 else
6434 /* Else, do the check that we postponed for Objective-C. */
6437 }
6439 /* Give an error for storing in something that is 'const'. */
6444 {
6447 }
6451 /* If storing into a structure or union member,
6452 it has probably been given type `int'.
6453 Compute the type that would go with
6454 the actual amount of storage the member occupies. */
6463 /* If storing in a field that is in actuality a short or narrower than one,
6464 we must store in the field in its actual type. */
6467 {
6470 }
6472 /* Issue -Wc++-compat warnings about an assignment to an enum type
6473 when LHS does not have its original type. This happens for,
6474 e.g., an enum bitfield in a struct. */
6479 {
6481 ? rhs_origtype
6488 }
6490 /* Remove qualifiers. */
6494 /* Convert new value to destination type. Fold it first, then
6495 restore any excess precision information, for the sake of
6496 conversion warnings. */
6499 {
6502 {
6504 {
6507 }
6512 }
6513 else
6520 }
6522 /* Emit ObjC write barrier, if necessary. */
6524 {
6527 {
6530 }
6531 }
6533 /* Scan operands. */
6537 else
6538 {
6542 }
6544 /* If we got the LHS in a different type for storing in,
6545 convert the result back to the nominal type of LHS
6546 so that the value we return always has the same type
6547 as the LHS argument. */
6557 return_result:
6561 }
6562 \f
6563 /* Return whether STRUCT_TYPE has an anonymous field with type TYPE.
6564 This is used to implement -fplan9-extensions. */
6566 static bool
6568 {
6569 tree field;
6577 {
6580 TYPE_QUAL_ATOMIC)
6584 {
6588 }
6592 {
6596 }
6597 }
6599 }
6601 /* RHS is an expression whose type is pointer to struct. If there is
6602 an anonymous field in RHS with type TYPE, then return a pointer to
6603 that field in RHS. This is used with -fplan9-extensions. This
6604 returns NULL if no conversion could be found. */
6606 static tree
6608 {
6612 tree ret;
6621 TYPE_QUAL_ATOMIC)
6629 {
6635 TYPE_QUAL_ATOMIC)
6638 {
6642 }
6644 lhs_main_type))
6645 {
6650 }
6651 }
6658 NULL_TREE);
6662 {
6665 }
6668 }
6670 /* Issue an error message for a bad initializer component.
6671 GMSGID identifies the message.
6672 The component name is taken from the spelling stack. */
6676 {
6679 auto_diagnostic_group d;
6681 /* The gmsgid may be a format string with %< and %>. */
6690 }
6692 /* Issue a pedantic warning for a bad initializer component. OPT is
6693 the option OPT_* (from options.h) controlling this warning or 0 if
6694 it is unconditionally given. GMSGID identifies the message. The
6695 component name is taken from the spelling stack. */
6699 {
6700 /* Use the location where a macro was expanded rather than where
6701 it was defined to make sure macros defined in system headers
6702 but used incorrectly elsewhere are diagnosed. */
6704 auto_diagnostic_group d;
6712 }
6714 /* Issue a warning for a bad initializer component.
6716 OPT is the OPT_W* value corresponding to the warning option that
6717 controls this warning. GMSGID identifies the message. The
6718 component name is taken from the spelling stack. */
6720 static void
6722 {
6726 auto_diagnostic_group d;
6728 /* Use the location where a macro was expanded rather than where
6729 it was defined to make sure macros defined in system headers
6730 but used incorrectly elsewhere are diagnosed. */
6733 /* The gmsgid may be a format string with %< and %>. */
6738 }
6739 \f
6740 /* If TYPE is an array type and EXPR is a parenthesized string
6741 constant, warn if pedantic that EXPR is being used to initialize an
6742 object of type TYPE. */
6744 void
6746 {
6753 }
6755 /* Attempt to locate the parameter with the given index within FNDECL,
6756 returning DECL_SOURCE_LOCATION (FNDECL) if it can't be found. */
6758 static location_t
6760 {
6762 tree param;
6764 /* Locate param by index within DECL_ARGUMENTS (fndecl). */
6768 ;
6770 /* If something went wrong (e.g. if we have a builtin and thus no arguments),
6771 return DECL_SOURCE_LOCATION (FNDECL). */
6776 }
6778 /* Issue a note about a mismatching argument for parameter PARMNUM
6779 to FUNDECL, for types EXPECTED_TYPE and ACTUAL_TYPE.
6780 Attempt to issue the note at the pertinent parameter of the decl;
6781 failing that issue it at the location of FUNDECL; failing that
6782 issue it at PLOC. */
6784 static void
6787 {
6788 location_t loc;
6791 else
6797 }
6799 /* Issue a warning when an argument of ARGTYPE is passed to a built-in
6800 function FUNDECL declared without prototype to parameter PARMNUM of
6801 PARMTYPE when ARGTYPE does not promote to PARMTYPE. */
6803 static void
6806 {
6811 /* Avoid warning for enum arguments that promote to an integer type
6812 of the same size/mode. */
6824 /* This diagnoses even signed/unsigned mismatches. Those might be
6825 safe in many cases but GCC may emit suboptimal code for them so
6826 warning on those cases drives efficiency improvements. */
6830 "in a call to built-in function declared without "
6833 "in a call to built-in function declared without "
6838 fundecl);
6839 }
6841 /* Convert value RHS to type TYPE as preparation for an assignment to
6842 an lvalue of type TYPE. If ORIGTYPE is not NULL_TREE, it is the
6843 original type of RHS; this differs from TREE_TYPE (RHS) for enum
6844 types. NULL_POINTER_CONSTANT says whether RHS was a null pointer
6845 constant before any folding.
6846 The real work of conversion is done by `convert'.
6847 The purpose of this function is to generate error messages
6848 for assignments that are not allowed in C.
6849 ERRTYPE says whether it is argument passing, assignment,
6850 initialization or return.
6852 In the following example, '~' denotes where EXPR_LOC and '^' where
6853 LOCATION point to:
6855 f (var); [ic_argpass]
6856 ^ ~~~
6857 x = var; [ic_assign]
6858 ^ ~~~;
6859 int x = var; [ic_init]
6860 ^^^
6861 return x; [ic_return]
6862 ^
6864 FUNCTION is a tree for the function being called.
6865 PARMNUM is the number of the argument, for printing in error messages.
6866 WARNOPT may be set to a warning option to issue the corresponding warning
6867 rather than an error for invalid conversions. Used for calls to built-in
6868 functions declared without a prototype. */
6870 static tree
6875 {
6878 tree rhstype;
6883 /* Use the expansion point location to handle cases such as user's
6884 function returning a wrong-type macro defined in a system header. */
6888 {
6889 tree selector;
6890 /* Change pointer to function to the function itself for
6891 diagnostics. */
6896 /* Handle an ObjC selector specially for diagnostics. */
6900 {
6903 }
6904 }
6906 /* This macro is used to emit diagnostics to ensure that all format
6907 strings are complete sentences, visible to gettext and checked at
6908 compile time. */
6909 #define PEDWARN_FOR_ASSIGNMENT(LOCATION, PLOC, OPT, AR, AS, IN, RE) \
6910 do { \
6911 switch (errtype) \
6912 { \
6913 case ic_argpass: \
6914 { \
6915 auto_diagnostic_group d; \
6916 if (pedwarn (PLOC, OPT, AR, parmnum, rname)) \
6917 inform_for_arg (fundecl, (PLOC), parmnum, type, rhstype); \
6918 } \
6919 break; \
6920 case ic_assign: \
6921 pedwarn (LOCATION, OPT, AS); \
6922 break; \
6923 case ic_init: \
6924 case ic_init_const: \
6925 pedwarn_init (LOCATION, OPT, IN); \
6926 break; \
6927 case ic_return: \
6928 pedwarn (LOCATION, OPT, RE); \
6929 break; \
6930 default: \
6931 gcc_unreachable (); \
6932 } \
6933 } while (0)
6935 /* This macro is used to emit diagnostics to ensure that all format
6936 strings are complete sentences, visible to gettext and checked at
6937 compile time. It can be called with 'pedwarn' or 'warning_at'. */
6938 #define WARNING_FOR_QUALIFIERS(PEDWARN, LOCATION, PLOC, OPT, AR, AS, IN, RE, QUALS) \
6939 do { \
6940 switch (errtype) \
6941 { \
6942 case ic_argpass: \
6943 { \
6944 auto_diagnostic_group d; \
6945 if (PEDWARN) { \
6946 if (pedwarn (PLOC, OPT, AR, parmnum, rname, QUALS)) \
6947 inform_for_arg (fundecl, (PLOC), parmnum, type, rhstype); \
6948 } else { \
6949 if (warning_at (PLOC, OPT, AR, parmnum, rname, QUALS)) \
6950 inform_for_arg (fundecl, (PLOC), parmnum, type, rhstype); \
6951 } \
6952 } \
6953 break; \
6954 case ic_assign: \
6955 if (PEDWARN) \
6956 pedwarn (LOCATION, OPT, AS, QUALS); \
6957 else \
6958 warning_at (LOCATION, OPT, AS, QUALS); \
6959 break; \
6960 case ic_init: \
6961 case ic_init_const: \
6962 if (PEDWARN) \
6963 pedwarn (LOCATION, OPT, IN, QUALS); \
6964 else \
6965 warning_at (LOCATION, OPT, IN, QUALS); \
6966 break; \
6967 case ic_return: \
6968 if (PEDWARN) \
6969 pedwarn (LOCATION, OPT, RE, QUALS); \
6970 else \
6971 warning_at (LOCATION, OPT, RE, QUALS); \
6972 break; \
6973 default: \
6974 gcc_unreachable (); \
6975 } \
6976 } while (0)
6978 /* This macro is used to emit diagnostics to ensure that all format
6979 strings are complete sentences, visible to gettext and checked at
6980 compile time. It is the same as PEDWARN_FOR_ASSIGNMENT but with an
6981 extra parameter to enumerate qualifiers. */
6982 #define PEDWARN_FOR_QUALIFIERS(LOCATION, PLOC, OPT, AR, AS, IN, RE, QUALS) \
6983 WARNING_FOR_QUALIFIERS (true, LOCATION, PLOC, OPT, AR, AS, IN, RE, QUALS)
6996 {
7000 {
7017 }
7020 }
7023 {
7029 {
7055 }
7056 }
7059 {
7065 {
7070 }
7071 }
7074 {
7077 }
7080 {
7081 /* Except for passing an argument to an unprototyped function,
7082 this is a constraint violation. When passing an argument to
7083 an unprototyped function, it is compile-time undefined;
7084 making it a constraint in that case was rejected in
7085 DR#252. */
7089 else
7092 }
7100 /* A non-reference type can convert to a reference. This handles
7101 va_start, va_copy and possibly port built-ins. */
7103 {
7105 {
7109 else
7112 }
7129 }
7130 /* Some types can interconvert without explicit casts. */
7134 /* Arithmetic types all interconvert, and enum is treated like int. */
7143 {
7146 rhstype);
7159 }
7161 /* Aggregates in different TUs might need conversion. */
7168 /* Conversion to a transparent union or record from its member types.
7169 This applies only to function arguments. */
7173 {
7177 {
7188 {
7192 /* Any non-function converts to a [const][volatile] void *
7193 and vice versa; otherwise, targets must be the same.
7194 Meanwhile, the lhs target must have all the qualifiers of
7195 the rhs. */
7199 {
7202 /* If this type won't generate any warnings, use it. */
7210 /* Keep looking for a better type, but remember this one. */
7213 }
7214 }
7216 /* Can convert integer zero to any pointer type. */
7218 {
7221 }
7222 }
7225 {
7227 {
7228 /* We have only a marginally acceptable member type;
7229 it needs a warning. */
7233 /* Const and volatile mean something different for function
7234 types, so the usual warnings are not appropriate. */
7237 {
7238 /* Because const and volatile on functions are
7239 restrictions that say the function will not do
7240 certain things, it is okay to use a const or volatile
7241 function where an ordinary one is wanted, but not
7242 vice-versa. */
7246 OPT_Wdiscarded_qualifiers,
7248 "makes %q#v qualified function "
7251 "function pointer from "
7254 "function pointer from "
7259 }
7263 OPT_Wdiscarded_qualifiers,
7275 }
7283 }
7284 }
7286 /* Conversions among pointers */
7289 {
7290 /* If RHS refers to a built-in declared without a prototype
7291 BLTIN is the declaration of the built-in with a prototype
7292 and RHSTYPE is set to the actual type of the built-in. */
7293 tree bltin;
7302 addr_space_t asl;
7303 addr_space_t asr;
7308 TYPE_QUAL_ATOMIC)
7313 TYPE_QUAL_ATOMIC)
7315 /* Opaque pointers are treated like void pointers. */
7318 /* The Plan 9 compiler permits a pointer to a struct to be
7319 automatically converted into a pointer to an anonymous field
7320 within the struct. */
7325 {
7328 {
7334 }
7335 }
7337 /* C++ does not allow the implicit conversion void* -> T*. However,
7338 for the purpose of reducing the number of false positives, we
7339 tolerate the special case of
7341 int *p = NULL;
7343 where NULL is typically defined in C to be '(void *) 0'. */
7346 OPT_Wc___compat,
7347 "request for implicit conversion "
7350 /* See if the pointers point to incompatible address spaces. */
7355 {
7356 auto_diagnostic_group d;
7359 {
7361 {
7365 diagnosed
7367 else
7370 }
7372 {
7377 else
7380 }
7383 {
7388 else
7391 }
7393 {
7398 else
7401 }
7404 }
7406 {
7409 else
7412 }
7414 }
7416 /* Check if the right-hand side has a format attribute but the
7417 left-hand side doesn't. */
7420 {
7422 {
7425 "argument %d of %qE might be "
7431 "assignment left-hand side might be "
7437 "initialization left-hand side might be "
7442 "return type might be "
7447 }
7448 }
7450 /* See if the pointers point to incompatible scalar storage orders. */
7455 {
7456 tree t;
7459 {
7461 /* Do not warn for built-in functions, for example memcpy, since we
7462 control how they behave and they can be useful in this area. */
7466 "passing argument %d of %qE from incompatible "
7470 /* Do not warn if the RHS is a call to a function that returns a
7471 pointer that is not an alias. */
7476 "assignment to %qT from pointer type %qT with "
7481 /* Likewise. */
7486 "initialization of %qT from pointer type %qT with "
7491 "returning %qT from pointer type with incompatible "
7496 }
7497 }
7499 /* Any non-function converts to a [const][volatile] void *
7500 and vice versa; otherwise, targets must be the same.
7501 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
7505 || is_opaque_pointer
7511 {
7512 /* Warn about loss of qualifers from pointers to arrays with
7513 qualifiers on the element type. */
7515 {
7523 OPT_Wdiscarded_array_qualifiers,
7533 }
7536 ||
7538 && !null_pointer_constant
7542 "%qE between function pointer "
7550 /* Const and volatile mean something different for function types,
7551 so the usual warnings are not appropriate. */
7554 {
7555 /* Assignments between atomic and non-atomic objects are OK. */
7561 /* Don't warn about loss of qualifier for conversions from
7562 qualified void* to pointers to arrays with corresponding
7563 qualifier on the element type (except for pedantic before C23). */
7566 OPT_Wdiscarded_qualifiers,
7580 /* If this is not a case of ignoring a mismatch in signedness,
7581 no warning. */
7584 ;
7585 /* If there is a mismatch, do warn. */
7588 {
7590 {
7591 auto_diagnostic_group d;
7595 "pointer targets in passing argument %d of "
7598 rhstype);
7599 }
7603 "pointer targets in assignment from %qT to %qT "
7609 "pointer targets in initialization of %qT "
7611 rhstype);
7615 "returning %qT from a function with return type "
7620 }
7621 }
7624 {
7625 /* Because const and volatile on functions are restrictions
7626 that say the function will not do certain things,
7627 it is okay to use a const or volatile function
7628 where an ordinary one is wanted, but not vice-versa. */
7632 OPT_Wdiscarded_qualifiers,
7634 "%q#v qualified function pointer "
7643 }
7644 }
7645 /* Avoid warning about the volatile ObjC EH puts on decls. */
7647 {
7649 {
7651 {
7652 auto_diagnostic_group d;
7656 "passing argument %d of %qE from incompatible "
7659 }
7664 "assignment to %qT from pointer to "
7667 else
7676 "initialization of %qT from pointer to "
7679 else
7681 "initialization of %qT from incompatible "
7688 "returning pointer to %qD of type %qT from "
7691 else
7693 "returning %qT from a function with incompatible "
7698 }
7699 }
7701 /* If RHS isn't an address, check pointer or array of packed
7702 struct or union. */
7706 }
7708 {
7709 /* ??? This should not be an error when inlining calls to
7710 unprototyped functions. */
7714 else
7717 }
7722 {
7723 /* An explicit constant 0 or type nullptr_t can convert to a pointer,
7724 or one that results from arithmetic, even including a cast to
7725 integer type. */
7728 {
7730 {
7731 auto_diagnostic_group d;
7735 "passing argument %d of %qE makes pointer from "
7738 }
7742 "assignment to %qT from %qT makes pointer from integer "
7748 "initialization of %qT from %qT makes pointer from "
7753 "function with return type %qT makes pointer from "
7758 }
7761 }
7764 {
7766 {
7768 {
7769 auto_diagnostic_group d;
7773 "passing argument %d of %qE makes integer from "
7776 }
7780 "assignment to %qT from %qT makes integer from pointer "
7786 "initialization of %qT from %qT makes integer from "
7791 "function with return type %qT makes integer from "
7796 }
7799 }
7801 /* The type nullptr_t may be converted to bool. The
7802 result is false. */
7804 {
7805 tree ret;
7811 }
7816 {
7818 {
7819 auto_diagnostic_group d;
7825 else
7828 }
7831 {
7836 else
7839 }
7842 {
7847 else
7850 }
7852 {
7857 else
7860 }
7863 }
7866 }
7867 \f
7868 /* If VALUE is a compound expr all of whose expressions are constant, then
7869 return its value. Otherwise, return error_mark_node.
7871 This is for handling COMPOUND_EXPRs as initializer elements
7872 which is allowed with a warning when -pedantic is specified. */
7874 static tree
7876 {
7878 {
7883 endtype);
7884 }
7887 else
7889 }
7890 \f
7891 /* Perform appropriate conversions on the initial value of a variable,
7892 store it in the declaration DECL,
7893 and print any error messages that are appropriate.
7894 If ORIGTYPE is not NULL_TREE, it is the original type of INIT.
7895 If the init is invalid, store an ERROR_MARK.
7897 INIT_LOC is the location of the initial value. */
7899 void
7901 {
7907 /* If variable's type was invalidly declared, just ignore it. */
7913 /* Digest the specified initializer into an expression. */
7916 {
7921 /* Not fully determined before folding. */
7923 }
7930 /* Store the expression if valid; else report error. */
7940 /* ANSI wants warnings about out-of-range constant initializers. */
7945 /* Check if we need to set array size from compound literal size. */
7949 {
7956 {
7960 {
7961 /* For int foo[] = (int [3]){1}; we need to set array size
7962 now since later on array initializer will be just the
7963 brace enclosed list of the compound literal. */
7971 }
7972 }
7973 }
7974 }
7975 \f
7976 /* Methods for storing and printing names for error messages. */
7978 /* Implement a spelling stack that allows components of a name to be pushed
7979 and popped. Each element on the stack is this structure. */
7981 struct spelling
7982 {
7984 union
7985 {
7989 };
7991 #define SPELLING_STRING 1
7992 #define SPELLING_MEMBER 2
7993 #define SPELLING_BOUNDS 3
7999 /* Macros to save and restore the spelling stack around push_... functions.
8000 Alternative to SAVE_SPELLING_STACK. */
8002 #define SPELLING_DEPTH() (spelling - spelling_base)
8003 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
8005 /* Push an element on the spelling stack with type KIND and assign VALUE
8006 to MEMBER. */
8008 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
8009 { \
8010 int depth = SPELLING_DEPTH (); \
8011 \
8012 if (depth >= spelling_size) \
8013 { \
8014 spelling_size += 10; \
8015 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
8016 spelling_size); \
8017 RESTORE_SPELLING_DEPTH (depth); \
8018 } \
8019 \
8020 spelling->kind = (KIND); \
8021 spelling->MEMBER = (VALUE); \
8022 spelling++; \
8023 }
8025 /* Push STRING on the stack. Printed literally. */
8027 static void
8029 {
8031 }
8033 /* Push a member name on the stack. Printed as '.' STRING. */
8035 static void
8037 {
8043 }
8045 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
8047 static void
8049 {
8051 }
8053 /* Compute the maximum size in bytes of the printed spelling. */
8055 static int
8057 {
8062 {
8065 else
8067 }
8070 }
8072 /* Print the spelling to BUFFER and return it. */
8076 {
8082 {
8085 }
8086 else
8087 {
8092 ;
8093 }
8096 }
8098 /* Check whether INIT, a floating or integer constant, is
8099 representable in TYPE, a real floating type with the same radix or
8100 a decimal floating type initialized with a binary floating
8101 constant. Return true if OK, false if not. */
8102 static bool
8104 {
8109 {
8110 /* Same mode, no conversion required except for the case of
8111 signaling NaNs if the types are incompatible (e.g. double and
8112 long double with the same mode). */
8118 }
8120 {
8126 }
8136 {
8137 /* This is valid if the real number represented by the
8138 initializer can be exactly represented in the decimal
8139 type. Compare the values using MPFR. */
8140 REAL_VALUE_TYPE t;
8153 }
8154 /* exact_real_truncate is not quite right here, since it doesn't
8155 allow even an exact conversion to subnormal values. */
8156 REAL_VALUE_TYPE t;
8159 }
8161 /* Check whether INIT (location LOC) is valid as a 'constexpr'
8162 initializer for type TYPE, and give an error if not. INIT has
8163 already been folded and verified to be constant. INT_CONST_EXPR
8164 and ARITH_CONST_EXPR say whether it is an integer constant
8165 expression or arithmetic constant expression, respectively. If
8166 TYPE is not a scalar type, this function does nothing. */
8168 static void
8171 {
8173 {
8174 /* The initializer must be null. */
8178 }
8180 {
8181 /* The initializer must be an integer constant expression,
8182 representable in the target type. */
8190 }
8191 /* We don't apply any extra checks to extension types such as vector
8192 or fixed-point types. */
8196 {
8200 }
8201 /* We don't apply any extra checks to complex integers. */
8205 /* Following N3082, a real type cannot be initialized from a complex
8206 type and a binary type cannot be initialized from a decimal type
8207 (but initializing a decimal type from a binary type is OK).
8208 Signaling NaN initializers are OK only if the types are
8209 compatible (not just the same mode); all quiet NaN and infinity
8210 initializations are considered to preserve the value. */
8213 {
8217 }
8222 {
8226 }
8229 {
8231 {
8244 }
8245 }
8246 else
8251 }
8253 /* Digest the parser output INIT as an initializer for type TYPE.
8254 Return a C expression of type TYPE to represent the initial value.
8256 If ORIGTYPE is not NULL_TREE, it is the original type of INIT.
8258 NULL_POINTER_CONSTANT is true if INIT is a null pointer constant,
8259 INT_CONST_EXPR is true if INIT is an integer constant expression,
8260 and ARITH_CONST_EXPR is true if INIT is, or might be, an arithmetic
8261 constant expression, false if it has already been determined in the
8262 caller that it is not (but folding may have made the value passed here
8263 indistinguishable from an arithmetic constant expression).
8265 If INIT is a string constant, STRICT_STRING is true if it is
8266 unparenthesized or we should not warn here for it being parenthesized.
8267 For other types of INIT, STRICT_STRING is not used.
8269 INIT_LOC is the location of the INIT.
8271 REQUIRE_CONSTANT requests an error if non-constant initializers or
8272 elements are seen. REQUIRE_CONSTEXPR means the stricter requirements
8273 on initializers for 'constexpr' objects apply. */
8275 static tree
8280 {
8287 || !init
8294 {
8296 {
8299 }
8301 }
8302 /* TODO: this may not detect all cases of expressions folding to
8303 constants that are not arithmetic constant expressions. */
8317 /* Initialization of an array of chars from a string constant
8318 optionally enclosed in braces. */
8322 {
8323 tree typ1
8326 TYPE_QUAL_ATOMIC)
8328 /* Note that an array could be both an array of character type
8329 and an array of wchar_t if wchar_t is signed char or unsigned
8330 char. */
8339 {
8358 {
8361 }
8366 {
8371 }
8375 {
8376 /* Check if all characters of the string can be
8377 represented in the type of the constexpr object being
8378 initialized. */
8385 {
8389 }
8390 }
8395 {
8399 /* Subtract the size of a single (possibly wide) character
8400 because it's ok to ignore the terminating null char
8401 that is counted in the length of the constant. */
8412 {
8413 unsigned HOST_WIDE_INT size
8418 }
8419 }
8423 }
8425 {
8429 }
8430 }
8432 /* Build a VECTOR_CST from a *constant* vector constructor. If the
8433 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
8434 below and handle as a constructor. */
8439 {
8446 {
8448 tree value;
8451 /* Iterate through elements and check if all constructor
8452 elements are *_CSTs. */
8455 {
8458 }
8463 }
8464 }
8469 /* Any type can be initialized
8470 from an expression of the same type, optionally with braces. */
8483 {
8485 {
8487 {
8490 inside_init = array_to_pointer_conversion
8492 else
8493 {
8496 }
8497 }
8498 }
8501 /* Although the types are compatible, we may require a
8502 conversion. */
8507 {
8508 /* As an extension, allow initializing objects with static storage
8509 duration with compound literals (which are then treated just as
8510 the brace enclosed list they contain). Also allow this for
8511 vectors, as we can only assign them with compound literals. */
8517 }
8521 {
8525 }
8527 /* Compound expressions can only occur here if -Wpedantic or
8528 -pedantic-errors is specified. In the later case, we always want
8529 an error. In the former case, we simply want a warning. */
8532 {
8533 inside_init
8538 else
8543 }
8547 {
8550 }
8558 /* Added to enable additional -Wsuggest-attribute=format warnings. */
8562 (require_constant
8563 ? ic_init_const
8567 }
8569 /* Handle scalar types, including conversions. */
8575 {
8583 inside_init);
8584 inside_init
8591 /* Check to see if we have already given an error message. */
8593 ;
8595 {
8598 }
8602 {
8606 }
8615 }
8617 /* Come here only for records and arrays. */
8620 {
8622 "variable-sized object may not be initialized except "
8625 }
8629 }
8630 \f
8631 /* Handle initializers that use braces. */
8633 /* Type of object we are accumulating a constructor for.
8634 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
8637 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
8638 left to fill. */
8641 /* For an ARRAY_TYPE, this is the specified index
8642 at which to store the next element we get. */
8645 /* For an ARRAY_TYPE, this is the maximum index. */
8648 /* For a RECORD_TYPE, this is the first field not yet written out. */
8651 /* For an ARRAY_TYPE, this is the index of the first element
8652 not yet written out. */
8655 /* In a RECORD_TYPE, the byte index of the next consecutive field.
8656 This is so we can generate gaps between fields, when appropriate. */
8659 /* If we are saving up the elements rather than allocating them,
8660 this is the list of elements so far (in reverse order,
8661 most recent first). */
8664 /* 1 if constructor should be incrementally stored into a constructor chain,
8665 0 if all the elements should be kept in AVL tree. */
8668 /* 1 if so far this constructor's elements are all compile-time constants. */
8671 /* 1 if so far this constructor's elements are all valid address constants. */
8674 /* 1 if this constructor has an element that cannot be part of a
8675 constant expression. */
8678 /* 1 if this constructor is erroneous so far. */
8681 /* 1 if this constructor is the universal zero initializer { 0 }. */
8684 /* Structure for managing pending initializer elements, organized as an
8685 AVL tree. */
8687 struct init_node
8688 {
8692 tree purpose;
8693 tree value;
8694 tree origtype;
8695 };
8697 /* Tree of pending elements at this constructor level.
8698 These are elements encountered out of order
8699 which belong at places we haven't reached yet in actually
8700 writing the output.
8701 Will never hold tree nodes across GC runs. */
8704 /* The SPELLING_DEPTH of this constructor. */
8707 /* DECL node for which an initializer is being read.
8708 0 means we are reading a constructor expression
8709 such as (struct foo) {...}. */
8712 /* Nonzero if there were any member designators in this initializer. */
8715 /* Nesting depth of designator list. */
8718 /* Nonzero if there were diagnosed errors in this designator list. */
8721 \f
8722 /* This stack has a level for each implicit or explicit level of
8723 structuring in the initializer, including the outermost one. It
8724 saves the values of most of the variables above. */
8728 struct constructor_stack
8729 {
8731 tree type;
8732 tree fields;
8733 tree index;
8734 tree max_index;
8735 tree unfilled_index;
8736 tree unfilled_fields;
8737 tree bit_index;
8742 /* If value nonzero, this value should replace the entire
8743 constructor at this level. */
8755 };
8759 /* This stack represents designators from some range designator up to
8760 the last designator in the list. */
8762 struct constructor_range_stack
8763 {
8766 tree range_start;
8767 tree index;
8768 tree range_end;
8769 tree fields;
8770 };
8774 /* This stack records separate initializers that are nested.
8775 Nested initializers can't happen in ANSI C, but GNU C allows them
8776 in cases like { ... (struct foo) { ... } ... }. */
8778 struct initializer_stack
8779 {
8781 tree decl;
8793 };
8796 \f
8797 /* Prepare to parse and output the initializer for variable DECL. */
8799 void
8803 {
8828 {
8829 require_constant_elements
8831 /* For a scalar, you can always use any value to initialize,
8832 even within braces. */
8835 }
8836 else
8837 {
8840 }
8853 }
8855 void
8857 {
8860 /* Free the whole constructor stack of this initializer. */
8862 {
8866 }
8870 /* Pop back to the data of the outer initializer (if any). */
8886 }
8887 \f
8888 /* Call here when we see the initializer is surrounded by braces.
8889 This is instead of a call to push_init_level;
8890 it is matched by a call to pop_init_level.
8892 TYPE is the type to initialize, for a constructor expression.
8893 For an initializer for a decl, TYPE is zero. */
8895 void
8897 {
8947 {
8949 /* Skip any nameless bit fields at the beginning. */
8956 }
8958 {
8960 {
8961 constructor_max_index
8964 /* Detect non-empty initializations of zero-length arrays. */
8969 /* constructor_max_index needs to be an INTEGER_CST. Attempts
8970 to initialize VLAs with a nonempty initializer will cause a
8971 proper error; avoid tree checking errors as well by setting a
8972 safe value. */
8977 constructor_index
8980 }
8981 else
8982 {
8985 }
8988 }
8990 {
8991 /* Vectors are like simple fixed-size arrays. */
8992 constructor_max_index =
8996 }
8997 else
8998 {
8999 /* Handle the case of int x = {5}; */
9002 }
9003 }
9004 \f
9007 /* Called when we see an open brace for a nested initializer. Finish
9008 off any pending levels with implicit braces. */
9009 void
9011 {
9013 {
9018 last_init_list_comma),
9021 && constructor_max_index
9023 constructor_index))
9026 last_init_list_comma),
9028 else
9030 }
9031 }
9033 /* Push down into a subobject, for initialization.
9034 If this is for an explicit set of braces, IMPLICIT is 0.
9035 If it is because the next element belongs at a lower level,
9036 IMPLICIT is 1 (or 2 if the push is because of designator list). */
9038 void
9041 {
9045 /* Unless this is an explicit brace, we need to preserve previous
9046 content if any. */
9048 {
9053 }
9088 /* If the upper initializer is designated, then mark this as
9089 designated too to prevent bogus warnings. */
9093 {
9098 }
9100 /* Don't die if an entire brace-pair level is superfluous
9101 in the containing level. */
9103 ;
9105 {
9106 /* Don't die if there are extra init elts at the end. */
9109 else
9110 {
9113 constructor_depth++;
9114 }
9115 }
9117 {
9120 constructor_depth++;
9121 }
9124 {
9129 }
9132 {
9141 }
9144 {
9149 }
9152 {
9154 /* Skip any nameless bit fields at the beginning. */
9161 }
9163 {
9164 /* Vectors are like simple fixed-size arrays. */
9165 constructor_max_index =
9169 }
9171 {
9173 {
9174 constructor_max_index
9177 /* Detect non-empty initializations of zero-length arrays. */
9182 /* constructor_max_index needs to be an INTEGER_CST. Attempts
9183 to initialize VLAs will cause a proper error; avoid tree
9184 checking errors as well by setting a safe value. */
9189 constructor_index
9192 }
9193 else
9198 {
9199 /* We need to split the char/wchar array into individual
9200 characters, so that we don't have to special case it
9201 everywhere. */
9203 }
9204 }
9205 else
9206 {
9211 }
9212 }
9214 /* At the end of an implicit or explicit brace level,
9215 finish up that level of constructor. If a single expression
9216 with redundant braces initialized that level, return the
9217 c_expr structure for that expression. Otherwise, the original_code
9218 element is set to ERROR_MARK.
9219 If we were outputting the elements as they are read, return 0 as the value
9220 from inner levels (process_init_element ignores that),
9221 but return error_mark_node as the value from the outermost level
9222 (that's what we want to put in DECL_INITIAL).
9223 Otherwise, return a CONSTRUCTOR expression as the value. */
9225 struct c_expr
9228 location_t insert_before)
9229 {
9238 {
9239 /* When we come to an explicit close brace,
9240 pop any inner levels that didn't have explicit braces. */
9244 insert_before),
9247 }
9248 else
9253 /* Now output all pending elements. */
9259 /* Error for initializing a flexible array member, or a zero-length
9260 array member in an inappropriate context. */
9265 {
9266 /* Silently discard empty initializations. The parser will
9267 already have pedwarned for empty brackets. */
9270 else
9271 {
9276 else
9280 /* We have already issued an error message for the existence
9281 of a flexible array member not at the end of the structure.
9282 Discard the initializer so that we do not die later. */
9285 }
9286 }
9289 {
9291 /* Initialization with { } counts as zeroinit. */
9295 /* This might be zeroinit as well. */
9300 /* If the constructor has more than one element, it can't be { 0 }. */
9303 }
9305 /* Warn when some structs are initialized with direct aggregation. */
9308 {
9311 OPT_Wmissing_braces,
9313 }
9315 /* Warn when some struct elements are implicitly initialized to zero. */
9317 && constructor_type
9320 {
9321 /* Do not warn for flexible array members or zero-length arrays. */
9328 /* Do not warn if this level of the initializer uses member
9329 designators; it is likely to be deliberate. */
9330 && !constructor_designated
9331 /* Do not warn about initializing with { 0 } or with { }. */
9333 {
9336 constructor_unfilled_fields,
9337 constructor_type))
9340 }
9341 }
9343 /* Pad out the end of the structure. */
9345 /* If this closes a superfluous brace pair,
9346 just pass out the element between them. */
9349 ;
9353 {
9354 /* A nonincremental scalar initializer--just return
9355 the element, after verifying there is just one.
9356 Empty scalar initializers are supported in C2X. */
9358 {
9362 {
9365 }
9367 /* Ensure this is a null pointer constant in the case of a
9368 'constexpr' object initialized with {}. */
9370 else
9372 }
9374 {
9377 }
9378 else
9380 }
9381 else
9382 {
9385 else
9386 {
9388 constructor_elements);
9395 }
9396 }
9399 {
9404 }
9433 }
9435 /* Common handling for both array range and field name designators.
9436 ARRAY argument is nonzero for array ranges. Returns false for success. */
9438 static bool
9441 {
9442 tree subtype;
9445 /* Don't die if an entire brace-pair level is superfluous
9446 in the containing level, or for an erroneous type. */
9450 /* If there were errors in this designator list already, bail out
9451 silently. */
9455 /* Likewise for an initializer for a variable-size type. Those are
9456 diagnosed in the parser, except for empty initializer braces. */
9462 {
9465 /* Designator list starts at the level of closest explicit
9466 braces. */
9470 last_init_list_comma),
9474 }
9477 {
9489 }
9493 {
9496 }
9498 {
9501 }
9507 }
9509 /* If there are range designators in designator list, push a new designator
9510 to constructor_range_stack. RANGE_END is end of such stack range or
9511 NULL_TREE if there is no range designator at this level. */
9513 static void
9515 {
9531 }
9533 /* Within an array initializer, specify the next index to be initialized.
9534 FIRST is that index. If LAST is nonzero, then initialize a range
9535 of indices, running from FIRST through LAST. */
9537 void
9540 {
9548 {
9551 }
9554 {
9558 "array index in initializer is not "
9560 }
9563 {
9567 "array index in initializer is not "
9569 }
9582 else
9583 {
9589 {
9592 }
9595 {
9599 {
9602 }
9603 else
9604 {
9608 {
9612 }
9613 }
9614 }
9616 designator_depth++;
9620 }
9621 }
9623 /* Within a struct initializer, specify the next field to be initialized. */
9625 void
9628 {
9629 tree field;
9637 {
9640 }
9645 {
9648 {
9654 }
9655 else
9658 }
9659 else
9660 do
9661 {
9663 designator_depth++;
9669 {
9672 }
9673 }
9675 }
9676 \f
9677 /* Add a new initializer to the tree of pending initializers. PURPOSE
9678 identifies the initializer, either array index or field in a structure.
9679 VALUE is the value of that index or field. If ORIGTYPE is not
9680 NULL_TREE, it is the original type of VALUE.
9682 IMPLICIT is true if value comes from pop_init_level (1),
9683 the new initializer has been merged with the existing one
9684 and thus no warnings should be emitted about overriding an
9685 existing initializer. */
9687 static void
9690 {
9697 {
9699 {
9705 else
9706 {
9708 {
9711 "initialized field with side-effects "
9716 }
9720 }
9721 }
9722 }
9723 else
9724 {
9725 tree bitpos;
9729 {
9735 else
9736 {
9738 {
9741 "initialized field with side-effects "
9746 }
9750 }
9751 }
9752 }
9767 {
9771 {
9775 {
9777 {
9778 /* L rotation. */
9791 {
9794 else
9796 }
9797 else
9799 }
9800 else
9801 {
9802 /* LR rotation. */
9824 {
9827 else
9829 }
9830 else
9832 }
9834 }
9835 else
9836 {
9837 /* p->balance == +1; growth of left side balances the node. */
9840 }
9841 }
9843 {
9845 /* Growth propagation from right side. */
9848 {
9850 {
9851 /* R rotation. */
9864 {
9867 else
9869 }
9870 else
9872 }
9874 {
9875 /* RL rotation */
9897 {
9900 else
9902 }
9903 else
9905 }
9907 }
9908 else
9909 {
9910 /* p->balance == -1; growth of right side balances the node. */
9913 }
9914 }
9918 }
9919 }
9921 /* Build AVL tree from a sorted chain. */
9923 static void
9925 {
9935 braced_init_obstack);
9938 {
9940 /* Skip any nameless bit fields at the beginning. */
9945 }
9947 {
9949 constructor_unfilled_index
9952 else
9954 }
9956 }
9958 /* Build AVL tree from a string constant. */
9960 static void
9963 {
9980 p < end
9981 && !(constructor_max_index
9984 {
9986 {
9989 }
9990 else
9991 {
9995 {
9998 else
10003 }
10004 }
10007 {
10010 {
10012 {
10015 }
10016 }
10018 {
10021 }
10025 }
10031 braced_init_obstack);
10032 }
10035 }
10037 /* Return value of FIELD in pending initializer or NULL_TREE if the field was
10038 not initialized yet. */
10040 static tree
10042 {
10046 {
10053 {
10058 else
10060 }
10061 }
10063 {
10067 && (!constructor_unfilled_fields
10074 {
10079 else
10081 }
10082 }
10084 {
10088 }
10090 }
10092 /* "Output" the next constructor element.
10093 At top level, really output it to assembler code now.
10094 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
10095 If ORIGTYPE is not NULL_TREE, it is the original type of VALUE.
10096 TYPE is the data type that the containing data type wants here.
10097 FIELD is the field (a FIELD_DECL) or the index that this element fills.
10098 If VALUE is a string constant, STRICT_STRING is true if it is
10099 unparenthesized or we should not warn here for it being parenthesized.
10100 For other types of VALUE, STRICT_STRING is not used.
10102 PENDING if true means output pending elements that belong
10103 right after this element. (PENDING is normally true;
10104 it is false while outputting pending elements, to avoid recursion.)
10106 IMPLICIT is true if value comes from pop_init_level (1),
10107 the new initializer has been merged with the existing one
10108 and thus no warnings should be emitted about overriding an
10109 existing initializer. */
10111 static void
10115 {
10121 {
10124 }
10137 {
10138 /* As an extension, allow initializing objects with static storage
10139 duration with compound literals (which are then treated just as
10140 the brace enclosed list they contain). */
10146 }
10152 /* Not fully determined before folding. */
10155 {
10158 }
10160 /* TODO: this may not detect all cases of expressions folding to
10161 constants that are not arithmetic constant expressions. */
10182 && TYPE_REVERSE_STORAGE_ORDER
10191 /* Digest the initializer and issue any errors about incompatible
10192 types before issuing errors about non-constant initializers. */
10196 /* In the case of braces around a scalar initializer, the result of
10197 this initializer processing goes through digest_init again at the
10198 outer level. In the case of a constexpr initializer for a
10199 pointer, avoid converting a null pointer constant to something
10200 that is not a null pointer constant to avoid a spurious error
10201 from that second processing. */
10203 || !npc
10209 {
10212 }
10216 /* Proceed to check the constness of the original initializer. */
10218 {
10220 {
10223 }
10227 }
10232 /* digest_init has already carried out the additional checks
10233 required for 'constexpr' initializers (using the information
10234 passed to it about whether the original initializer was certain
10235 kinds of constant expression), so that check does not need to be
10236 repeated here. */
10238 /* Issue -Wc++-compat warnings about initializing a bitfield with
10239 enum type. */
10247 {
10254 }
10256 /* If this field is empty and does not have side effects (and is not at
10257 the end of structure), don't do anything other than checking the
10258 initializer. */
10268 /* Finally, set VALUE to the initializer value digested above. */
10271 /* If this element doesn't come next in sequence,
10272 put it on constructor_pending_elts. */
10274 && (!constructor_incremental
10276 {
10282 braced_init_obstack);
10284 }
10286 && (!constructor_incremental
10288 {
10289 /* We do this for records but not for unions. In a union,
10290 no matter which field is specified, it can be initialized
10291 right away since it starts at the beginning of the union. */
10293 {
10296 else
10297 {
10305 }
10306 }
10309 braced_init_obstack);
10311 }
10314 {
10316 {
10323 }
10325 /* We can have just one union field set. */
10327 }
10329 /* Otherwise, output this element either to
10330 constructor_elements or to the assembler file. */
10335 /* Advance the variable that indicates sequential elements output. */
10337 constructor_unfilled_index
10339 bitsize_one_node);
10341 {
10342 constructor_unfilled_fields
10345 /* Skip any nameless bit fields. */
10348 constructor_unfilled_fields =
10350 }
10354 /* Now output any pending elements which have become next. */
10357 }
10359 /* For two FIELD_DECLs in the same chain, return -1 if field1
10360 comes before field2, 1 if field1 comes after field2 and
10361 0 if field1 == field2. */
10363 static int
10365 {
10372 {
10373 /* If one of the fields has non-zero bitsize, then that
10374 field must be the last one in a sequence of zero
10375 sized fields, fields after it will have bigger
10376 bit_position. */
10385 /* Otherwise, fallback to DECL_CHAIN walk to find out
10386 which field comes earlier. Walk chains of both
10387 fields, so that if field1 and field2 are close to each
10388 other in either order, it is found soon even for large
10389 sequences of zero sized fields. */
10392 {
10396 {
10399 }
10410 }
10411 }
10414 else
10416 }
10418 /* Output any pending elements which have become next.
10419 As we output elements, constructor_unfilled_{fields,index}
10420 advances, which may cause other elements to become next;
10421 if so, they too are output.
10423 If ALL is 0, we return when there are
10424 no more pending elements to output now.
10426 If ALL is 1, we output space as necessary so that
10427 we can output all the pending elements. */
10428 static void
10430 {
10432 tree next;
10434 retry:
10436 /* Look through the whole pending tree.
10437 If we find an element that should be output now,
10438 output it. Otherwise, set NEXT to the element
10439 that comes first among those still pending. */
10443 {
10445 {
10447 constructor_unfilled_index))
10451 braced_init_obstack);
10454 {
10455 /* Advance to the next smaller node. */
10458 else
10459 {
10460 /* We have reached the smallest node bigger than the
10461 current unfilled index. Fill the space first. */
10464 }
10465 }
10466 else
10467 {
10468 /* Advance to the next bigger node. */
10471 else
10472 {
10473 /* We have reached the biggest node in a subtree. Find
10474 the parent of it, which is the next bigger node. */
10480 {
10483 }
10484 }
10485 }
10486 }
10488 {
10489 /* If the current record is complete we are done. */
10499 braced_init_obstack);
10501 {
10502 /* Advance to the next smaller node. */
10505 else
10506 {
10507 /* We have reached the smallest node bigger than the
10508 current unfilled field. Fill the space first. */
10511 }
10512 }
10513 else
10514 {
10515 /* Advance to the next bigger node. */
10518 else
10519 {
10520 /* We have reached the biggest node in a subtree. Find
10521 the parent of it, which is the next bigger node. */
10528 {
10531 }
10532 }
10533 }
10534 }
10535 }
10537 /* Ordinarily return, but not if we want to output all
10538 and there are elements left. */
10542 /* If it's not incremental, just skip over the gap, so that after
10543 jumping to retry we will output the next successive element. */
10549 /* ELT now points to the node in the pending tree with the next
10550 initializer to output. */
10552 }
10553 \f
10554 /* Expression VALUE coincides with the start of type TYPE in a braced
10555 initializer. Return true if we should treat VALUE as initializing
10556 the first element of TYPE, false if we should treat it as initializing
10557 TYPE as a whole.
10559 If the initializer is clearly invalid, the question becomes:
10560 which choice gives the best error message? */
10562 static bool
10564 {
10574 /* GNU vectors can be initialized elementwise. However, treat any
10575 kind of vector value as initializing the vector type as a whole,
10576 regardless of whether the value is a GNU vector. Such initializers
10577 are valid if and only if they would have been valid in a non-braced
10578 initializer like:
10580 TYPE foo = VALUE;
10582 so recursing into the vector type would be at best confusing or at
10583 worst wrong. For example, when -flax-vector-conversions is in effect,
10584 it's possible to initialize a V8HI from a V4SI, even though the vectors
10585 have different element types and different numbers of elements. */
10593 }
10595 /* Add one non-braced element to the current constructor level.
10596 This adjusts the current position within the constructor's type.
10597 This may also start or terminate implicit levels
10598 to handle a partly-braced initializer.
10600 Once this has found the correct level for the new element,
10601 it calls output_init_element.
10603 IMPLICIT is true if value comes from pop_init_level (1),
10604 the new initializer has been merged with the existing one
10605 and thus no warnings should be emitted about overriding an
10606 existing initializer. */
10608 void
10611 {
10613 int string_flag
10624 /* Handle superfluous braces around string cst as in
10625 char x[] = {"foo"}; */
10627 && !was_designated
10631 {
10633 {
10636 }
10638 {
10641 }
10642 }
10645 {
10648 }
10650 /* Ignore elements of a brace group if it is entirely superfluous
10651 and has already been diagnosed, or if the type is erroneous. */
10655 /* Ignore elements of an initializer for a variable-size type.
10656 Those are diagnosed in the parser (empty initializer braces are OK). */
10666 OPT_Wdesignated_init,
10667 "positional initialization of field "
10670 /* If we've exhausted any levels that didn't have braces,
10671 pop them now. */
10673 {
10678 last_init_list_comma),
10682 && constructor_max_index
10684 constructor_index))
10687 last_init_list_comma),
10689 else
10691 }
10693 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
10695 {
10696 /* If value is a compound literal and we'll be just using its
10697 content, don't put it into a SAVE_EXPR. */
10700 {
10703 {
10706 }
10711 }
10712 }
10715 {
10717 {
10718 tree fieldtype;
10722 {
10725 }
10732 /* Error for non-static initialization of a flexible array member. */
10734 && !require_constant_value
10737 {
10741 }
10743 /* Error for initialization of a flexible array member with
10744 a string constant if the structure is in an array. E.g.:
10745 struct S { int x; char y[]; };
10746 struct S s[] = { { 1, "foo" } };
10747 is invalid. */
10753 {
10758 {
10761 }
10763 {
10767 }
10768 }
10770 /* Accept a string constant to initialize a subarray. */
10776 /* Otherwise, if we have come to a subaggregate,
10777 and we don't have an element of its type, push into it. */
10780 {
10783 }
10786 {
10791 braced_init_obstack);
10793 }
10794 else
10795 /* Do the bookkeeping for an element that was
10796 directly output as a constructor. */
10797 {
10798 /* For a record, keep track of end position of last field. */
10800 constructor_bit_index
10805 /* If the current field was the first one not yet written out,
10806 it isn't now, so update. */
10808 {
10810 /* Skip any nameless bit fields. */
10812 && (DECL_UNNAMED_BIT_FIELD
10814 constructor_unfilled_fields =
10816 }
10817 }
10820 /* Skip any nameless bit fields at the beginning. */
10824 }
10826 {
10827 tree fieldtype;
10831 {
10835 }
10842 /* Warn that traditional C rejects initialization of unions.
10843 We skip the warning if the value is zero. This is done
10844 under the assumption that the zero initializer in user
10845 code appears conditioned on e.g. __STDC__ to avoid
10846 "missing initializer" warnings and relies on default
10847 initialization to zero in the traditional C case.
10848 We also skip the warning if the initializer is designated,
10849 again on the assumption that this must be conditional on
10850 __STDC__ anyway (and we've already complained about the
10851 member-designator already). */
10858 /* Accept a string constant to initialize a subarray. */
10864 /* Otherwise, if we have come to a subaggregate,
10865 and we don't have an element of its type, push into it. */
10868 {
10871 }
10874 {
10879 braced_init_obstack);
10881 }
10882 else
10883 /* Do the bookkeeping for an element that was
10884 directly output as a constructor. */
10885 {
10888 }
10891 }
10893 {
10897 /* Accept a string constant to initialize a subarray. */
10903 /* Otherwise, if we have come to a subaggregate,
10904 and we don't have an element of its type, push into it. */
10907 {
10910 }
10915 {
10919 }
10921 /* Now output the actual element. */
10923 {
10928 braced_init_obstack);
10930 }
10932 constructor_index
10937 /* If we are doing the bookkeeping for an element that was
10938 directly output as a constructor, we must update
10939 constructor_unfilled_index. */
10941 }
10943 {
10946 /* Do a basic check of initializer size. Note that vectors
10947 always have a fixed size derived from their type. */
10949 {
10953 }
10955 /* Now output the actual element. */
10957 {
10963 braced_init_obstack);
10964 }
10966 constructor_index
10971 /* If we are doing the bookkeeping for an element that was
10972 directly output as a constructor, we must update
10973 constructor_unfilled_index. */
10975 }
10977 /* Handle the sole element allowed in a braced initializer
10978 for a scalar variable. */
10981 {
10985 }
10986 else
10987 {
10992 braced_init_obstack);
10994 }
10996 /* Handle range initializers either at this level or anywhere higher
10997 in the designator stack. */
10999 {
11006 {
11010 braced_init_obstack,
11011 last_init_list_comma),
11013 }
11017 {
11021 braced_init_obstack,
11022 last_init_list_comma),
11024 }
11032 {
11036 {
11039 }
11048 }
11053 }
11056 }
11059 }
11060 \f
11061 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
11062 (guaranteed to be 'volatile' or null) and ARGS (represented using
11063 an ASM_EXPR node). */
11064 tree
11066 {
11070 }
11072 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
11073 some INPUTS, and some CLOBBERS. The latter three may be NULL.
11074 SIMPLE indicates whether there was anything at all after the
11075 string in the asm expression -- asm("blah") and asm("blah" : )
11076 are subtly different. We use a ASM_EXPR node to represent this.
11077 LOC is the location of the asm, and IS_INLINE says whether this
11078 is asm inline. */
11079 tree
11082 {
11083 tree tail;
11084 tree args;
11097 /* Remove output conversions that change the type but not the mode. */
11099 {
11104 /* ??? Really, this should not be here. Users should be using a
11105 proper lvalue, dammit. But there's a long history of using casts
11106 in the output operands. In cases like longlong.h, this becomes a
11107 primitive form of typechecking -- if the cast can be removed, then
11108 the output operand had a type of the proper width; otherwise we'll
11109 get an error. Gross, but ... */
11127 {
11128 /* If the operand is going to end up in memory,
11129 mark it addressable. */
11135 {
11138 }
11139 }
11140 else
11144 }
11147 {
11148 tree input;
11155 {
11156 /* If the operand is going to end up in memory,
11157 mark it addressable. */
11159 {
11162 /* Strip the nops as we allow this case. FIXME, this really
11163 should be rejected or made deprecated. */
11167 }
11168 else
11169 {
11177 {
11180 }
11181 }
11182 }
11183 else
11187 }
11191 /* asm statements without outputs, including simple ones, are treated
11192 as volatile. */
11198 }
11199 \f
11200 /* Generate a goto statement to LABEL. LOC is the location of the
11201 GOTO. */
11203 tree
11205 {
11210 {
11215 }
11216 }
11218 /* Generate a computed goto statement to EXPR. LOC is the location of
11219 the GOTO. */
11221 tree
11223 {
11225 tree t;
11230 {
11234 }
11240 }
11242 /* Generate a C `return' statement. RETVAL is the expression for what
11243 to return, or a null pointer for `return;' with no value. LOC is
11244 the location of the return statement, or the location of the expression,
11245 if the statement has any. If ORIGTYPE is not NULL_TREE, it
11246 is the original type of RETVAL. */
11248 tree
11250 {
11255 /* Use the expansion point to handle cases such as returning NULL
11256 in a function returning void. */
11264 {
11268 {
11271 }
11277 }
11280 {
11284 {
11287 warned_here = pedwarn
11290 else
11291 warned_here = warning_at
11298 }
11299 }
11301 {
11305 warned_here = pedwarn
11308 else
11309 warned_here = pedwarn
11315 }
11316 else
11317 {
11322 tree inner;
11340 /* Strip any conversions, additions, and subtractions, and see if
11341 we are returning the address of a local variable. Warn if so. */
11343 {
11345 {
11346 CASE_CONVERT:
11354 /* If the second operand of the MINUS_EXPR has a pointer
11355 type (or is converted from it), this may be valid, so
11356 don't give a warning. */
11357 {
11370 }
11384 {
11388 else
11389 {
11394 }
11395 }
11400 }
11403 }
11410 }
11416 }
11417 \f
11419 /* The SWITCH_STMT being built. */
11420 tree switch_stmt;
11422 /* The original type of the testing expression, i.e. before the
11423 default conversion is applied. */
11424 tree orig_type;
11426 /* A splay-tree mapping the low element of a case range to the high
11427 element, or NULL_TREE if there is no high element. Used to
11428 determine whether or not a new case label duplicates an old case
11429 label. We need a tree, rather than simply a hash table, because
11430 of the GNU case range extension. */
11431 splay_tree cases;
11433 /* The bindings at the point of the switch. This is used for
11434 warnings crossing decls when branching to a case label. */
11437 /* Whether the switch includes any break statements. */
11440 /* The next node on the stack. */
11443 /* Remember whether the controlling expression had boolean type
11444 before integer promotions for the sake of -Wswitch-bool. */
11446 };
11448 /* A stack of the currently active switch statements. The innermost
11449 switch statement is on the top of the stack. There is no need to
11450 mark the stack for garbage collection because it is only active
11451 during the processing of the body of a function, and we never
11452 collect at that point. */
11456 /* Start a C switch statement, testing expression EXP. Return the new
11457 SWITCH_STMT. SWITCH_LOC is the location of the `switch'.
11458 SWITCH_COND_LOC is the location of the switch's condition.
11459 EXPLICIT_CAST_P is true if the expression EXP has an explicit cast. */
11461 tree
11463 location_t switch_cond_loc,
11465 {
11471 {
11475 {
11477 {
11480 }
11482 }
11483 else
11484 {
11488 /* Warn if the condition has boolean value. */
11494 /* Explicit cast to int suppresses this warning. */
11511 }
11512 }
11514 /* Add this new SWITCH_STMT to the stack. */
11527 }
11529 /* Process a case label at location LOC, with attributes ATTRS. */
11531 tree
11533 {
11537 {
11542 }
11545 {
11550 }
11553 {
11556 else
11559 }
11563 loc))
11572 }
11574 /* Finish the switch statement. TYPE is the original type of the
11575 controlling expression of the switch, or NULL_TREE. */
11577 void
11579 {
11581 location_t switch_location;
11585 /* Emit warnings as needed. */
11595 /* Pop the stack. */
11600 }
11601 \f
11602 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
11603 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
11604 may be null. */
11606 void
11608 tree else_block)
11609 {
11610 tree stmt;
11615 }
11617 tree
11619 {
11620 /* In switch statements break is sometimes stylistically used after
11621 a return statement. This can lead to spurious warnings about
11622 control reaching the end of a non-void function when it is
11623 inlined. Note that we are calling block_may_fallthru with
11624 language specific tree nodes; this works because
11625 block_may_fallthru returns true when given something it does not
11626 understand. */
11631 {
11648 }
11649 else
11651 {
11664 }
11670 {
11671 /* The foreach expander produces low-level code using gotos instead
11672 of a structured loop construct. */
11675 }
11677 }
11679 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
11681 static void
11683 {
11688 ;
11690 {
11694 }
11696 {
11700 {
11704 }
11712 }
11713 else
11715 }
11717 /* Process an expression as if it were a complete statement. Emit
11718 diagnostics, but do not call ADD_STMT. LOC is the location of the
11719 statement. */
11721 tree
11723 {
11724 tree exprv;
11739 /* If we're not processing a statement expression, warn about unused values.
11740 Warnings for statement expressions will be emitted later, once we figure
11741 out which is the result. */
11756 /* If the expression is not of a type to which we cannot assign a line
11757 number, wrap the thing in a no-op NOP_EXPR. */
11759 {
11762 }
11765 }
11767 /* Emit an expression as a statement. LOC is the location of the
11768 expression. */
11770 tree
11772 {
11775 else
11777 }
11779 /* Do the opposite and emit a statement as an expression. To begin,
11780 create a new binding level and return it. */
11782 tree
11784 {
11785 tree ret;
11787 /* We must force a BLOCK for this level so that, if it is not expanded
11788 later, there is a way to turn off the entire subtree of blocks that
11789 are contained in it. */
11794 ? NULL
11797 /* Mark the current statement list as belonging to a statement list. */
11801 }
11803 /* LOC is the location of the compound statement to which this body
11804 belongs. */
11806 tree
11808 {
11815 ? NULL
11818 /* Locate the last statement in BODY. See c_end_compound_stmt
11819 about always returning a BIND_EXPR. */
11823 continue_searching:
11825 {
11831 /* This can happen with degenerate cases like ({ }). No value. */
11835 /* If we're supposed to generate side effects warnings, process
11836 all of the statements except the last. */
11838 {
11841 {
11842 location_t tloc;
11847 }
11848 }
11851 }
11853 /* If the end of the list is exception related, then the list was split
11854 by a call to push_cleanup. Continue searching. */
11857 {
11861 }
11866 /* In the case that the BIND_EXPR is not necessary, return the
11867 expression out from inside it. */
11869 /* Skip nested debug stmts. */
11872 {
11873 /* Even if this looks constant, do not allow it in a constant
11874 expression. */
11876 /* Do not warn if the return value of a statement expression is
11877 unused. */
11880 }
11882 /* Extract the type of said expression. */
11885 /* If we're not returning a value at all, then the BIND_EXPR that
11886 we already have is a fine expression to return. */
11890 /* Now that we've located the expression containing the value, it seems
11891 silly to make voidify_wrapper_expr repeat the process. Create a
11892 temporary of the appropriate type and stick it in a TARGET_EXPR. */
11895 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
11896 tree_expr_nonnegative_p giving up immediately. */
11905 {
11909 }
11910 }
11911 \f
11912 /* Begin and end compound statements. This is as simple as pushing
11913 and popping new statement lists from the tree. */
11915 tree
11917 {
11922 }
11924 /* End a compound statement. STMT is the statement. LOC is the
11925 location of the compound statement-- this is usually the location
11926 of the opening brace. */
11928 tree
11930 {
11934 {
11938 }
11943 /* If this compound statement is nested immediately inside a statement
11944 expression, then force a BIND_EXPR to be created. Otherwise we'll
11945 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
11946 STATEMENT_LISTs merge, and thus we can lose track of what statement
11947 was really last. */
11951 {
11955 }
11958 }
11960 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
11961 when the current scope is exited. EH_ONLY is true when this is not
11962 meant to apply to normal control flow transfer. */
11964 void
11966 {
11978 }
11979 \f
11980 /* Build a vector comparison of ARG0 and ARG1 using CODE opcode
11981 into a value of TYPE type. Comparison is done via VEC_COND_EXPR. */
11983 static tree
11986 {
11992 }
11994 /* Possibly warn about an address of OP never being NULL in a comparison
11995 operation CODE involving null. */
11997 static void
11999 {
12000 /* Prevent warnings issued for macro expansion. */
12007 {
12008 /* Allow casts to intptr_t to suppress the warning. */
12013 }
12016 {
12017 /* Allow a cast to void* to suppress the warning. */
12022 /* Adding any value to a null pointer, including zero, is undefined
12023 in C. This includes the expression &p[0] where p is the null
12024 pointer, although &p[0] will have been folded to p by this point
12025 and so not diagnosed. */
12028 "the comparison will always evaluate as %<false%> "
12030 op);
12031 else
12033 "the comparison will always evaluate as %<true%> "
12035 op);
12038 }
12047 {
12048 /* The address of either complex part may not be null. */
12051 "the comparison will always evaluate as %<false%> "
12053 op);
12054 else
12056 "the comparison will always evaluate as %<true%> "
12058 op);
12060 }
12062 /* Set to true in the loop below if OP dereferences is operand.
12063 In such a case the ultimate target need not be a decl for
12064 the null [in]equality test to be constant. */
12067 /* Get the outermost array or object, or member. */
12069 {
12071 {
12072 /* Get the member (its address is never null). */
12075 }
12077 /* Get the outer array/object to refer to in the warning. */
12080 }
12089 "the comparison will always evaluate as %<false%> "
12091 op);
12092 else
12094 "the comparison will always evaluate as %<true%> "
12096 op);
12100 }
12102 /* Build a binary-operation expression without default conversions.
12103 CODE is the kind of expression to build.
12104 LOCATION is the operator's location.
12105 This function differs from `build' in several ways:
12106 the data type of the result is computed and recorded in it,
12107 warnings are generated if arg data types are invalid,
12108 special handling for addition and subtraction of pointers is known,
12109 and some optimization is done (operations on narrow ints
12110 are done in the narrower type when that gives the same result).
12111 Constant folding is also done before the result is returned.
12113 Note that the operands will never have enumeral types, or function
12114 or array types, because either they will have the default conversions
12115 performed or they have both just been converted to some other type in which
12116 the arithmetic is to be done. */
12118 tree
12121 {
12123 tree eptype;
12131 /* Expression code to give to the expression when it is built.
12132 Normally this is CODE, which is what the caller asked for,
12133 but in some special cases we change it. */
12136 /* Data type in which the computation is to be performed.
12137 In the simplest cases this is the common type of the arguments. */
12140 /* When the computation is in excess precision, the type of the
12141 final EXCESS_PRECISION_EXPR. */
12144 /* Nonzero means operands have already been type-converted
12145 in whatever way is necessary.
12146 Zero means they need to be converted to RESULT_TYPE. */
12149 /* Nonzero means create the expression with this type, rather than
12150 RESULT_TYPE. */
12153 /* Nonzero means after finally constructing the expression
12154 convert it to this type. */
12157 /* Nonzero if this is an operation like MIN or MAX which can
12158 safely be computed in short if both args are promoted shorts.
12159 Also implies COMMON.
12160 -1 indicates a bitwise operation; this makes a difference
12161 in the exact conditions for when it is safe to do the operation
12162 in a narrower mode. */
12165 /* Nonzero if this is a comparison operation;
12166 if both args are promoted shorts, compare the original shorts.
12167 Also implies COMMON. */
12170 /* Nonzero if this is a right-shift operation, which can be computed on the
12171 original short and then promoted if the operand is a promoted short. */
12174 /* Nonzero means set RESULT_TYPE to the common type of the args. */
12177 /* True means types are compatible as far as ObjC is concerned. */
12180 /* True means this is an arithmetic operation that may need excess
12181 precision. */
12184 /* True means this is a boolean operation that converts both its
12185 operands to truth-values. */
12188 /* Remember whether we're doing / or %. */
12191 /* Remember whether we're doing << or >>. */
12194 /* Tree holding instrumentation expression. */
12211 {
12214 int_const = (int_const_or_overflow
12217 }
12218 else
12221 /* Do not apply default conversion in mixed vector/scalar expression. */
12224 {
12227 }
12233 /* The expression codes of the data types of the arguments tell us
12234 whether the arguments are integers, floating, pointers, etc. */
12238 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
12242 /* If an error was already reported for one of the arguments,
12243 avoid reporting another error. */
12258 {
12261 }
12264 {
12282 /* Excess precision for implicit conversions of integers to
12283 floating point in C11 and later. */
12284 may_need_excess_precision = (flag_isoc11
12292 }
12294 {
12297 }
12300 {
12303 }
12305 {
12308 }
12311 {
12314 }
12318 /* In case when one of the operands of the binary operation is
12319 a vector and another is a scalar -- convert scalar to vector. */
12322 {
12327 {
12331 {
12333 tree sc;
12344 }
12346 {
12348 tree sc;
12359 }
12362 }
12363 }
12366 {
12368 /* Handle the pointer + int case. */
12371 {
12374 }
12377 {
12380 }
12381 else
12386 /* Subtraction of two similar pointers.
12387 We must subtract them as integers, then divide by object size. */
12390 {
12393 }
12394 /* Handle pointer minus int. Just like pointer plus int. */
12397 {
12400 }
12401 else
12425 {
12437 else
12438 /* Although it would be tempting to shorten always here, that
12439 loses on some targets, since the modulo instruction is
12440 undefined if the quotient can't be represented in the
12441 computation mode. We shorten only if unsigned or if
12442 dividing by something we know != -1. */
12445 }
12454 /* Allow vector types which are not floating point types. */
12474 {
12475 /* Although it would be tempting to shorten always here, that loses
12476 on some targets, since the modulo instruction is undefined if the
12477 quotient can't be represented in the computation mode. We shorten
12478 only if unsigned or if dividing by something we know != -1. */
12481 }
12497 {
12498 /* Result of these operations is always an int,
12499 but that does not mean the operands should be
12500 converted to ints! */
12503 {
12506 }
12507 else
12510 {
12513 }
12514 else
12518 }
12520 {
12521 int_const_or_overflow = (int_operands
12525 int_const = (int_const_or_overflow
12529 }
12531 {
12532 int_const_or_overflow = (int_operands
12536 int_const = (int_const_or_overflow
12540 }
12543 /* Shift operations: result has same type as first operand;
12544 always convert second operand to int.
12545 Also set SHORT_SHIFT if shifting rightward. */
12554 {
12557 }
12563 {
12566 {
12568 {
12573 }
12575 {
12579 {
12584 }
12585 }
12586 else
12587 {
12592 {
12597 }
12598 }
12599 }
12601 /* Use the type of the value to be shifted. */
12603 /* Avoid converting op1 to result_type later. */
12605 }
12615 {
12618 }
12624 {
12629 {
12630 /* Don't reject a left shift of a negative value in a context
12631 where a constant expression is needed in C90. */
12637 }
12639 {
12641 {
12646 }
12648 {
12652 {
12657 }
12658 }
12660 {
12665 }
12670 }
12672 /* Use the type of the value to be shifted. */
12674 /* Avoid converting op1 to result_type later. */
12676 }
12682 {
12683 tree intt;
12685 {
12689 }
12693 {
12697 }
12699 /* It's not precisely specified how the usual arithmetic
12700 conversions apply to the vector types. Here, we use
12701 the unsigned type if one of the operands is signed and
12702 the other one is unsigned. */
12704 {
12707 else
12711 }
12713 /* Always construct signed integer vector type. */
12715 (SCALAR_TYPE_MODE
12718 {
12723 }
12729 }
12732 OPT_Wfloat_equal,
12734 /* Result of comparison is always int,
12735 but don't convert the args to int! */
12746 {
12749 }
12753 {
12756 }
12758 {
12765 /* Anything compares with void *. void * compares with anything.
12766 Otherwise, the targets must be compatible
12767 and both must be object or both incomplete. */
12771 {
12775 }
12777 {
12781 }
12783 {
12787 }
12788 else
12789 /* Avoid warning about the volatile ObjC EH puts on decls. */
12795 {
12797 result_type = build_pointer_type
12799 }
12800 }
12803 {
12806 }
12809 {
12812 }
12813 /* 6.5.9: One of the following shall hold:
12814 -- both operands have type nullptr_t; */
12816 {
12818 /* No need to convert the operands to result_type later. */
12820 }
12821 /* -- one operand has type nullptr_t and the other is a null pointer
12822 constant. We will have to convert the former to the type of the
12823 latter, because during gimplification we can't have mismatching
12824 comparison operand type. We convert from nullptr_t to the other
12825 type, since only nullptr_t can be converted to nullptr_t. Also,
12826 even a constant 0 is a null pointer constant, so we may have to
12827 create a pointer type from its type. */
12846 {
12847 tree intt;
12849 {
12853 }
12857 {
12861 }
12863 /* It's not precisely specified how the usual arithmetic
12864 conversions apply to the vector types. Here, we use
12865 the unsigned type if one of the operands is signed and
12866 the other one is unsigned. */
12868 {
12871 else
12875 }
12877 /* Always construct signed integer vector type. */
12879 (SCALAR_TYPE_MODE
12882 {
12887 }
12893 }
12901 {
12904 addr_space_t as_common;
12907 {
12921 }
12923 {
12927 }
12928 else
12929 {
12931 result_type = build_pointer_type
12935 }
12936 }
12938 {
12946 }
12948 {
12956 }
12959 {
12962 }
12965 {
12968 }
12973 {
12979 }
12990 /* Used for OpenMP atomics. */
12997 }
13006 {
13008 maybe_range_label_for_tree_type_mismatch
13015 }
13023 {
13029 {
13032 "implicit conversion from %qT to %qT "
13033 "to match other operand of binary "
13035 location);
13038 }
13047 {
13048 /* An operation on mixed real/complex operands must be
13049 handled specially, but the language-independent code can
13050 more easily optimize the plain complex arithmetic if
13051 -fno-signed-zeros. */
13055 {
13058 }
13060 {
13065 }
13066 else
13067 {
13072 }
13076 {
13083 {
13088 /* Fall through. */
13095 }
13096 }
13097 else
13098 {
13105 {
13109 /* Fall through. */
13119 }
13120 }
13123 }
13125 /* For certain operations (which identify themselves by shorten != 0)
13126 if both args were extended from the same smaller type,
13127 do the arithmetic in that type and then extend.
13129 shorten !=0 and !=1 indicates a bitwise operation.
13130 For them, this optimization is safe only if
13131 both args are zero-extended or both are sign-extended.
13132 Otherwise, we might change the result.
13133 Eg, (short)-1 | (unsigned short)-1 is (int)-1
13134 but calculated in (unsigned short) it would be (unsigned short)-1. */
13137 {
13141 }
13143 /* Shifts can be shortened if shifting right. */
13146 {
13157 /* We can shorten only if the shift count is less than the
13158 number of bits in the smaller type size. */
13160 /* We cannot drop an unsigned shift after sign-extension. */
13162 {
13163 /* Do an unsigned shift if the operand was zero-extended. */
13164 result_type
13167 /* Convert value-to-be-shifted to that type. */
13171 }
13172 }
13174 /* Comparison operations are shortened too but differently.
13175 They identify themselves by setting short_compare = 1. */
13178 {
13179 /* Don't write &op0, etc., because that would prevent op0
13180 from being kept in a register.
13181 Instead, make copies of the our local variables and
13182 pass the copies by reference, then copy them back afterward. */
13185 tree val
13190 {
13193 }
13200 {
13206 {
13209 }
13210 else
13211 {
13212 /* Fold for the sake of possible warnings, as in
13213 build_conditional_expr. This requires the
13214 "original" values to be folded, not just op0 and
13215 op1. */
13216 c_inhibit_evaluation_warnings++;
13221 c_inhibit_evaluation_warnings--;
13223 require_constant_value,
13224 NULL);
13226 require_constant_value,
13227 NULL);
13228 }
13235 {
13240 }
13241 }
13242 }
13243 }
13245 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
13246 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
13247 Then the expression will be built.
13248 It will be given type FINAL_TYPE if that is nonzero;
13249 otherwise, it will be given type RESULT_TYPE. */
13252 {
13253 /* Favor showing any expression locations that are available. */
13258 }
13261 {
13265 {
13268 }
13269 }
13272 {
13274 semantic_result_type);
13276 semantic_result_type);
13278 /* This can happen if one operand has a vector type, and the other
13279 has a different type. */
13282 }
13285 | SANITIZE_DIVIDE
13286 | SANITIZE_FLOAT_DIVIDE
13291 {
13292 /* OP0 and/or OP1 might have side-effects. */
13298 | SANITIZE_FLOAT_DIVIDE
13303 }
13305 /* Treat expressions in initializers specially as they can't trap. */
13307 ret = (require_constant_value
13311 else
13316 return_build_binary_op:
13319 ret = (int_operands
13336 }
13339 /* Convert EXPR to be a truth-value, validating its type for this
13340 purpose. LOCATION is the source location for the expression. */
13342 tree
13344 {
13348 {
13350 error_at (location, "used array that cannot be converted to pointer where scalar is required");
13379 }
13384 {
13389 }
13390 else
13391 /* ??? Should we also give an error for vectors rather than leaving
13392 those to give errors later? */
13396 {
13399 else
13401 }
13405 }
13406 \f
13408 /* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as
13409 required. */
13411 tree
13413 {
13415 {
13417 /* Executing a compound literal inside a function reinitializes
13418 it. */
13422 }
13423 else
13425 }
13426 \f
13427 /* Generate OMP construct CODE, with BODY and CLAUSES as its compound
13428 statement. LOC is the location of the construct. */
13430 tree
13432 tree clauses)
13433 {
13443 }
13445 /* Generate OACC_DATA, with CLAUSES and BLOCK as its compound
13446 statement. LOC is the location of the OACC_DATA. */
13448 tree
13450 {
13451 tree stmt;
13462 }
13464 /* Generate OACC_HOST_DATA, with CLAUSES and BLOCK as its compound
13465 statement. LOC is the location of the OACC_HOST_DATA. */
13467 tree
13469 {
13470 tree stmt;
13481 }
13483 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
13485 tree
13487 {
13488 tree block;
13494 }
13496 /* Generate OMP_PARALLEL, with CLAUSES and BLOCK as its compound
13497 statement. LOC is the location of the OMP_PARALLEL. */
13499 tree
13501 {
13502 tree stmt;
13513 }
13515 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
13517 tree
13519 {
13520 tree block;
13526 }
13528 /* Generate OMP_TASK, with CLAUSES and BLOCK as its compound
13529 statement. LOC is the location of the #pragma. */
13531 tree
13533 {
13534 tree stmt;
13545 }
13547 /* Generate GOMP_cancel call for #pragma omp cancel. */
13549 void
13551 {
13562 else
13563 {
13565 "%<parallel%>, %<for%>, %<sections%> or %<taskgroup%> "
13568 }
13571 {
13576 else
13577 {
13580 {
13586 }
13587 }
13593 }
13594 else
13598 ifc);
13600 }
13602 /* Generate GOMP_cancellation_point call for
13603 #pragma omp cancellation point. */
13605 void
13607 {
13618 else
13619 {
13621 "%<parallel%>, %<for%>, %<sections%> or %<taskgroup%> "
13624 }
13628 }
13630 /* Helper function for handle_omp_array_sections. Called recursively
13631 to handle multiple array-section-subscripts. C is the clause,
13632 T current expression (initially OMP_CLAUSE_DECL), which is either
13633 a TREE_LIST for array-section-subscript (TREE_PURPOSE is low-bound
13634 expression if specified, TREE_VALUE length expression if specified,
13635 TREE_CHAIN is what it has been specified after, or some decl.
13636 TYPES vector is populated with array section types, MAYBE_ZERO_LEN
13637 set to true if any of the array-section-subscript could have length
13638 of zero (explicit or implicit), FIRST_NON_ONE is the index of the
13639 first array-section-subscript which is known not to have length
13640 of one. Given say:
13641 map(a[:b][2:1][:c][:2][:d][e:f][2:5])
13642 FIRST_NON_ONE will be 3, array-section-subscript [:b], [2:1] and [:c]
13643 all are or may have length of 1, array-section-subscript [:2] is the
13644 first one known not to have length 1. For array-section-subscript
13645 <= FIRST_NON_ONE we diagnose non-contiguous arrays if low bound isn't
13646 0 or length isn't the array domain max + 1, for > FIRST_NON_ONE we
13647 can if MAYBE_ZERO_LEN is false. MAYBE_ZERO_LEN will be true in the above
13648 case though, as some lengths could be zero. */
13650 static tree
13654 {
13657 {
13664 {
13668 }
13670 {
13675 }
13677 {
13680 }
13685 {
13687 {
13692 }
13694 {
13696 {
13700 }
13705 {
13710 }
13712 {
13717 else
13719 }
13720 }
13721 }
13723 {
13728 else
13733 }
13737 {
13741 }
13746 {
13751 }
13756 {
13757 /* If the array section is pointer based and the pointer
13758 itself is _Atomic qualified, we need to atomically load
13759 the pointer. */
13760 c_expr expr;
13766 }
13768 }
13783 {
13786 low_bound);
13788 }
13790 {
13793 length);
13795 }
13811 {
13813 {
13818 }
13819 }
13821 {
13823 {
13829 {
13831 {
13836 }
13837 }
13838 else
13840 }
13843 first_non_one++;
13844 }
13846 {
13850 {
13852 "for unknown bound array type length expression must "
13855 }
13858 {
13863 }
13867 {
13872 }
13877 {
13878 tree size
13882 {
13884 {
13886 "low bound %qE above array section size "
13890 }
13892 {
13898 {
13903 }
13905 }
13908 && tree_int_cst_equal
13910 low_bound))
13911 first_non_one++;
13912 }
13914 {
13922 first_non_one++;
13923 }
13925 {
13927 {
13929 "length %qE above array section size "
13933 }
13935 {
13936 tree lbpluslen
13942 {
13944 "high bound %qE above array section size "
13948 }
13949 }
13950 }
13951 }
13953 {
13961 first_non_one++;
13962 }
13964 /* For [lb:] we will need to evaluate lb more than once. */
13966 {
13969 {
13972 }
13973 }
13974 }
13976 {
13978 {
13981 "for array function parameter length expression "
13983 else
13987 }
13991 {
13996 }
13997 /* If there is a pointer type anywhere but in the very first
13998 array-section-subscript, the array section could be non-contiguous. */
14002 {
14003 /* If any prior dimension has a non-one length, then deem this
14004 array section as non-contiguous. */
14007 {
14010 {
14015 }
14016 }
14017 }
14018 }
14019 else
14020 {
14024 }
14027 /* We will need to evaluate lb more than once. */
14030 {
14033 }
14036 }
14038 /* Handle array sections for clause C. */
14040 static bool
14042 {
14055 ort);
14062 {
14065 /* Need to evaluate side effects in the length expressions
14066 if any. */
14068 {
14070 {
14073 else
14076 }
14078 }
14083 }
14084 else
14085 {
14095 {
14099 i--;
14113 {
14122 {
14123 tree size;
14126 size_one_node);
14128 {
14129 do_warn_noncontiguous:
14131 "array section is not contiguous in %qs "
14135 }
14136 }
14139 {
14142 else
14146 }
14147 }
14148 else
14149 {
14150 tree l;
14160 else
14161 {
14164 size_one_node);
14167 }
14169 {
14171 size_zero_node);
14174 else
14177 }
14179 {
14187 {
14190 {
14195 }
14198 }
14203 }
14204 else
14206 }
14207 }
14213 {
14236 else
14237 {
14242 }
14245 }
14259 {
14278 }
14282 else
14302 }
14304 }
14306 /* Helper function of finish_omp_clauses. Clone STMT as if we were making
14307 an inline call. But, remap
14308 the OMP_DECL1 VAR_DECL (omp_out resp. omp_orig) to PLACEHOLDER
14309 and OMP_DECL2 VAR_DECL (omp_in resp. omp_priv) to DECL. */
14311 static tree
14314 {
14315 copy_body_data id;
14333 }
14335 /* Helper function of c_finish_omp_clauses, called via walk_tree.
14336 Find OMP_CLAUSE_PLACEHOLDER (passed in DATA) in *TP. */
14338 static tree
14340 {
14344 }
14346 /* Similarly, but also walk aggregate fields. */
14350 static tree
14352 {
14356 {
14357 tree field;
14363 {
14372 pset);
14378 }
14379 }
14384 }
14386 /* Finish OpenMP iterators ITER. Return true if they are errorneous
14387 and clauses containing them should be removed. */
14389 static bool
14391 {
14394 {
14399 tree orig_step;
14403 {
14406 }
14408 {
14410 var);
14413 }
14415 {
14419 }
14421 {
14425 }
14428 {
14431 }
14433 {
14438 }
14445 {
14452 }
14454 {
14458 }
14464 {
14467 }
14469 tree it2;
14471 {
14480 {
14485 }
14487 {
14491 }
14493 {
14497 }
14499 {
14503 }
14504 }
14506 {
14509 }
14514 }
14516 }
14518 /* Ensure that pointers are used in OpenACC attach and detach clauses.
14519 Return true if an error has been detected. */
14521 static bool
14523 {
14527 /* OpenACC attach / detach clauses must be pointers. */
14530 {
14537 {
14541 }
14542 }
14545 }
14547 /* For all elements of CLAUSES, validate them against their constraints.
14548 Remove any elements from the list that are invalid. */
14550 tree
14552 {
14572 /* 1 if normal/task reduction has been seen, -1 if inscan reduction
14573 has been seen, -2 if mixed inscan/normal reduction diagnosed. */
14584 /* If ort == C_ORT_OMP_DECLARE_SIMD used as uniform_head instead. */
14588 /* If ort == C_ORT_OMP used as nontemporal_head or use_device_xxx_head
14589 instead and for ort == C_ORT_OMP_TARGET used as in_reduction_head. */
14596 {
14599 }
14604 {
14609 /* We've reached the end of a list of expanded nodes. Reset the group
14610 start pointer. */
14615 {
14631 {
14633 "%<inscan%> and non-%<inscan%> %<reduction%> clauses "
14636 }
14637 /* FALLTHRU */
14643 {
14645 {
14648 }
14653 {
14655 "%<inscan%> %<reduction%> clause with array "
14659 }
14660 }
14663 {
14666 }
14673 {
14679 {
14682 t);
14685 }
14689 {
14692 t);
14695 }
14700 index_type);
14707 }
14709 {
14714 }
14717 {
14718 /* Disallow zero sized or potentially zero sized task
14719 reductions. */
14721 {
14727 }
14729 {
14735 }
14736 }
14740 {
14745 {
14771 }
14773 {
14779 }
14780 }
14782 {
14787 }
14789 {
14799 {
14805 }
14815 decl_placeholder ? decl_placeholder
14823 {
14835 decl_placeholder ? decl_placeholder
14838 {
14843 }
14845 c_find_omp_placeholder_r,
14848 }
14849 else
14850 {
14851 tree init;
14855 else
14859 }
14865 }
14867 {
14871 {
14876 }
14882 }
14888 {
14890 "%<nowait%> clause must not be used together "
14894 }
14900 {
14905 }
14915 {
14917 "modifier should not be specified in %<linear%> "
14918 "clause on %<simd%> or %<for%> constructs when not "
14921 }
14924 {
14926 "linear clause applied to non-integral non-pointer "
14930 }
14932 {
14937 }
14939 {
14942 {
14944 /* map_head bitmap is used as uniform_head if
14945 declare_simd. */
14949 }
14951 {
14953 "%<linear%> clause step %qE is neither constant "
14957 }
14958 }
14960 {
14966 fold_convert
14971 }
14972 else
14977 check_dup_generic:
14979 check_dup_generic_t:
14981 {
14986 }
14995 {
14999 {
15001 "%qD appears more than once in data-sharing "
15005 }
15009 {
15011 ort == C_ORT_ACC
15014 t);
15016 }
15017 else
15019 }
15024 {
15028 }
15033 {
15037 else
15041 }
15042 else
15048 {
15049 move_implicit:
15051 /* Move firstprivate and map clauses with
15052 OMP_CLAUSE_{FIRSTPRIVATE,MAP}_IMPLICIT set to the end of
15053 clauses chain. */
15059 {
15063 }
15066 {
15070 }
15071 else
15077 }
15082 {
15086 }
15094 {
15098 }
15100 {
15107 else
15111 }
15112 else
15121 {
15125 }
15128 {
15132 }
15133 else
15140 {
15144 }
15147 {
15149 "%qE in %<aligned%> clause is neither a pointer nor "
15152 }
15154 {
15159 }
15161 {
15164 t);
15166 }
15167 else
15174 {
15178 }
15180 {
15182 "%qE appears more than once in %<nontemporal%> "
15185 }
15186 else
15193 {
15197 }
15199 {
15202 t);
15204 }
15205 else
15206 {
15210 }
15218 {
15221 {
15224 {
15232 sizetype,
15236 {
15239 }
15241 }
15242 }
15244 }
15252 {
15254 last_iterators_remove
15260 }
15261 else
15264 {
15269 {
15271 "%<depend%> clause with %<depobj%> dependence "
15274 }
15276 }
15281 {
15284 {
15286 "%<omp_all_memory%> used with %<depend%> kind "
15289 }
15290 }
15292 {
15294 "%qE is not lvalue expression nor array section in "
15298 }
15301 {
15308 }
15311 {
15313 {
15315 "%qE does not have %<omp_depend_t%> type in "
15316 "%<depend%> clause with %<depobj%> dependence "
15319 }
15320 }
15323 {
15325 "%qE should not have %<omp_depend_t%> type in "
15326 "%<depend%> clause with dependence type other than "
15329 }
15331 {
15334 else
15335 {
15339 {
15342 }
15344 RO_UNARY_STAR);
15346 {
15349 }
15350 }
15356 else
15358 }
15364 /* FALLTHRU */
15370 {
15376 else
15377 {
15380 {
15382 "array section does not have mappable type "
15386 }
15388 {
15393 }
15398 {
15399 do
15400 {
15404 {
15409 }
15410 }
15420 {
15423 }
15427 {
15430 "%qD appears more than once in motion "
15434 "%qD appears more than once in data "
15436 else
15438 "%qD appears more than once in map "
15441 }
15442 else
15443 {
15446 }
15447 }
15448 }
15454 /* In this case, we have a single array element which is a
15455 pointer, and we already set OMP_CLAUSE_SIZE in
15456 handle_omp_array_sections above. For attach/detach clauses,
15457 reset the OMP_CLAUSE_SIZE (representing a bias) to zero
15458 here. */
15461 }
15463 {
15466 }
15467 /* OpenACC attach / detach clauses must be pointers. */
15469 {
15472 }
15476 /* For attach/detach clauses, set OMP_CLAUSE_SIZE (representing a
15477 bias) to zero here, so it is not set erroneously to the pointer
15478 size later on in gimplify.cc. */
15482 {
15487 }
15489 {
15492 }
15498 {
15504 }
15508 {
15510 {
15515 }
15517 {
15522 }
15524 {
15529 }
15531 {
15534 {
15539 }
15542 {
15547 else
15549 }
15553 {
15558 }
15559 }
15563 {
15568 }
15569 }
15571 {
15576 }
15578 {
15583 }
15587 && !indir_component_ref_p
15598 {
15603 }
15607 {
15612 }
15621 {
15625 {
15629 }
15632 {
15636 else
15640 }
15641 else
15643 }
15646 {
15653 else
15657 }
15660 {
15664 }
15667 {
15671 else
15675 }
15676 else
15677 {
15682 }
15695 ;
15697 {
15700 "%qE is neither a variable nor a function name in "
15702 else
15706 }
15708 {
15711 cname);
15713 }
15715 {
15718 cname);
15720 }
15724 {
15726 "%qE appears more than once on the same "
15729 }
15730 else
15737 {
15741 else
15746 }
15747 /* map_head bitmap is used as uniform_head if declare_simd. */
15757 {
15760 {
15765 }
15767 {
15772 }
15773 }
15779 {
15782 else
15783 {
15787 }
15788 }
15802 {
15804 "%<nowait%> clause must not be used together "
15808 }
15815 {
15817 "%<order%> clause must not be used together "
15821 }
15823 {
15824 /* Silently remove duplicates. */
15827 }
15835 {
15841 }
15909 {
15911 "%<order%> clause must not be used together "
15915 }
15931 {
15933 "%<inbranch%> clause is incompatible with "
15937 }
15948 {
15953 }
15958 }
15961 {
15965 {
15969 }
15972 {
15978 {
15985 /* The __func__ variable and similar function-local
15986 predefined variables may be listed in a shared or
15987 firstprivate clause. */
15996 }
15998 {
16004 }
16008 {
16010 "%<const%> qualified %qE may appear only in "
16013 }
16014 }
16015 }
16018 {
16020 {
16021 /* If we found a clause to remove, we want to remove the whole
16022 expanded group, otherwise gimplify
16023 (omp_resolve_clause_dependencies) can get confused. */
16027 }
16028 else
16030 }
16031 else
16033 }
16036 && safelen
16039 {
16041 "%<simdlen%> clause value is bigger than "
16045 }
16048 && schedule_clause
16051 {
16053 "%<nonmonotonic%> schedule modifier specified together "
16059 }
16062 {
16064 "%qs clause specified together with %<inscan%> "
16067 }
16070 {
16072 "%qs clause specified together with %<inscan%> "
16075 }
16079 || allocate_seen
16082 {
16086 {
16091 {
16101 }
16102 /* FALLTHRU */
16113 }
16118 {
16120 "%<linear%> clause step is a parameter %qD not "
16124 }
16130 {
16141 }
16145 else
16147 }
16151 {
16156 {
16158 "%qD specified in %<allocate%> clause but not in "
16161 }
16164 else
16166 }
16169 {
16171 "%<nogroup%> clause must not be used together with "
16174 }
16177 {
16179 {
16181 "%<detach%> clause must not be used together with "
16184 }
16185 else
16186 {
16190 {
16197 {
16199 "the event handle of a %<detach%> clause "
16202 }
16205 else
16207 }
16208 }
16209 }
16213 }
16215 /* Return code to initialize DST with a copy constructor from SRC.
16216 C doesn't have copy constructors nor assignment operators, only for
16217 _Atomic vars we need to perform __atomic_load from src into a temporary
16218 followed by __atomic_store of the temporary to dst. */
16220 tree
16222 {
16237 /* Expansion of a generic atomic load may require an addition
16238 element, so allocate enough to prevent a resize. */
16241 /* Build __atomic_load (&src, &tmp, SEQ_CST); */
16250 /* Build __atomic_store (&dst, &tmp, SEQ_CST); */
16257 }
16259 /* Create a transaction node. */
16261 tree
16263 {
16270 }
16272 /* Make a variant type in the proper way for C/C++, propagating qualifiers
16273 down to the element type of an array. If ORIG_QUAL_TYPE is not
16274 NULL, then it should be used as the qualified type
16275 ORIG_QUAL_INDIRECT levels down in array type derivation (to
16276 preserve information about the typedef name from which an array
16277 type was derived). */
16279 tree
16282 {
16287 {
16288 tree t;
16293 /* See if we already have an identically qualified type. */
16296 else
16298 {
16305 }
16307 {
16318 {
16319 tree unqualified_canon
16324 {
16325 unqualified_canon
16328 }
16331 }
16332 else
16334 }
16336 }
16338 /* A restrict-qualified pointer type must be a pointer to object or
16339 incomplete type. Note that the use of POINTER_TYPE_P also allows
16340 REFERENCE_TYPEs, which is appropriate for C++. */
16344 {
16347 }
16350 ? orig_qual_type
16352 /* A variant type does not inherit the list of incomplete vars from the
16353 type main variant. */
16359 }
16361 /* Build a VA_ARG_EXPR for the C parser. */
16363 tree
16365 {
16368 /* VA_ARG_EXPR cannot be used for a scalar va_list with reverse storage
16369 order because it takes the address of the expression. */
16372 {
16375 }
16377 {
16381 }
16383 {
16385 type);
16387 }
16392 }
16394 /* Return truthvalue of whether T1 is the same tree structure as T2.
16395 Return 1 if they are the same. Return false if they are different. */
16397 bool
16399 {
16414 /* They might have become equal now. */
16425 {
16449 /* We need to do this when determining whether or not two
16450 non-type pointer to member function template arguments
16451 are the same. */
16455 {
16459 {
16464 }
16465 }
16479 {
16494 }
16497 {
16501 /* Special case: if either target is an unallocated VAR_DECL,
16502 it means that it's going to be unified with whatever the
16503 TARGET_EXPR is really supposed to initialize, so treat it
16504 as being equivalent to anything. */
16515 }
16532 {
16541 }
16543 CASE_CONVERT:
16550 }
16553 {
16561 {
16565 {
16577 }
16588 }
16594 }
16595 }
16597 /* Returns true when the function declaration FNDECL is implicit,
16598 introduced as a result of a call to an otherwise undeclared
16599 function, and false otherwise. */
16601 bool
16603 {
16605 }