| blob | b21cac0bfb0b616b24283c2f2407bdb5902ee7de |
1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
23 /* This file is part of the C front end.
24 It contains routines to build C expressions given their operands,
25 including computing the types of the result, C-specific error checks,
26 and some optimization.
28 There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
29 and to process initializations in declarations (since they work
30 like a strange sort of assignment). */
46 /* Nonzero if we've already printed a "missing braces around initializer"
47 message within this initializer. */
50 /* 1 if we explained undeclared var errors. */
85 \f
86 /* Do `exp = require_complete_type (exp);' to make sure exp
87 does not have an incomplete type. (That includes void types.) */
89 tree
91 tree value;
92 {
98 /* First, detect a valid value with a complete type. */
104 }
106 /* Print an error message for invalid use of an incomplete type.
107 VALUE is the expression that was used (or 0 if that isn't known)
108 and TYPE is the type that was invalid. */
110 void
112 tree value;
113 tree type;
114 {
117 /* Avoid duplicate error message. */
125 else
126 {
127 retry:
128 /* We must print an error message. Be clever about what it says. */
131 {
150 {
152 {
155 }
158 }
164 }
169 else
170 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
173 }
174 }
176 /* Return a variant of TYPE which has all the type qualifiers of LIKE
177 as well as those of TYPE. */
179 static tree
182 {
185 }
186 \f
187 /* Return the common type of two types.
188 We assume that comptypes has already been done and returned 1;
189 if that isn't so, this may crash. In particular, we assume that qualifiers
190 match.
192 This is the type for the result of most arithmetic operations
193 if the operands have the given two types. */
195 tree
198 {
201 tree attributes;
203 /* Save time if the two types are the same. */
207 /* If one type is nonsense, use the other. */
213 /* Merge the attributes. */
216 /* Treat an enum type as the unsigned integer type of the same width. */
226 /* If one type is complex, form the common type of the non-complex
227 components, then make that complex. Use T1 or T2 if it is the
228 required type. */
230 {
239 else
241 attributes);
242 }
245 {
248 /* If only one is real, use it as the result. */
256 /* Both real or both integers; use the one with greater precision. */
263 /* Same precision. Prefer longs to ints even when same size. */
268 attributes);
272 {
273 /* But preserve unsignedness from the other type,
274 since long cannot hold all the values of an unsigned int. */
277 else
280 }
282 /* Likewise, prefer long double to double even if same size. */
286 attributes);
288 /* Otherwise prefer the unsigned one. */
292 else
296 /* For two pointers, do this recursively on the target type,
297 and combine the qualifiers of the two types' targets. */
298 /* This code was turned off; I don't know why.
299 But ANSI C specifies doing this with the qualifiers.
300 So I turned it on again. */
301 {
311 }
312 #if 0
315 #endif
318 {
320 /* Save space: see if the result is identical to one of the args. */
325 /* Merge the element types, and have a size if either arg has one. */
328 }
331 /* Function types: prefer the one that specified arg types.
332 If both do, merge the arg types. Also merge the return types. */
333 {
341 /* Save space: see if the result is identical to one of the args. */
347 /* Simple way if one arg fails to specify argument types. */
349 {
352 }
354 {
357 }
359 /* If both args specify argument types, we must merge the two
360 lists, argument by argument. */
375 {
376 /* A null type means arg type is not specified.
377 Take whatever the other function type has. */
379 {
382 }
384 {
387 }
389 /* Given wait (union {union wait *u; int *i} *)
390 and wait (union wait *),
391 prefer union wait * as type of parm. */
394 {
395 tree memb;
399 {
404 }
405 }
408 {
409 tree memb;
413 {
418 }
419 }
421 parm_done: ;
422 }
427 /* ... falls through ... */
428 }
432 }
434 }
435 \f
436 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
437 or various other operations. Return 2 if they are compatible
438 but a warning may be needed if you use them together. */
440 int
443 {
448 /* Suppress errors caused by previously reported errors. */
454 /* If either type is the internal version of sizetype, return the
455 language version. */
464 /* Treat an enum type as the integer type of the same width and
465 signedness. */
475 /* Different classes of types can't be compatible. */
479 /* Qualifiers must match. */
484 /* Allow for two different type nodes which have essentially the same
485 definition. Note that we already checked for equality of the type
486 qualifiers (just above). */
491 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
495 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
499 {
510 {
517 /* Target types must match incl. qualifiers. */
522 /* Sizes must match unless one is missing or variable. */
529 d1_variable = (! d1_zero
532 d2_variable = (! d2_zero
546 }
555 }
557 }
559 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
560 ignoring their qualifiers. */
562 static int
565 {
568 /* Give maybe_objc_comptypes a crack at letting these types through. */
578 }
579 \f
580 /* Subroutines of `comptypes'. */
582 /* Return 1 if two function types F1 and F2 are compatible.
583 If either type specifies no argument types,
584 the other must specify a fixed number of self-promoting arg types.
585 Otherwise, if one type specifies only the number of arguments,
586 the other must specify that number of self-promoting arg types.
587 Otherwise, the argument types must match. */
589 static int
592 {
594 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
605 /* An unspecified parmlist matches any specified parmlist
606 whose argument types don't need default promotions. */
609 {
612 /* If one of these types comes from a non-prototype fn definition,
613 compare that with the other type's arglist.
614 If they don't match, ask for a warning (but no error). */
619 }
621 {
628 }
630 /* Both types have argument lists: compare them and propagate results. */
633 }
635 /* Check two lists of types for compatibility,
636 returning 0 for incompatible, 1 for compatible,
637 or 2 for compatible with warning. */
639 static int
642 {
643 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
648 {
651 /* If one list is shorter than the other,
652 they fail to match. */
655 /* A null pointer instead of a type
656 means there is supposed to be an argument
657 but nothing is specified about what type it has.
658 So match anything that self-promotes. */
660 {
663 }
665 {
668 }
671 {
672 /* Allow wait (union {union wait *u; int *i} *)
673 and wait (union wait *) to be compatible. */
680 {
681 tree memb;
688 }
695 {
696 tree memb;
703 }
704 else
706 }
708 /* comptypes said ok, but record if it said to warn. */
714 }
715 }
716 \f
717 /* Compute the value of the `sizeof' operator. */
719 tree
721 tree type;
722 {
724 tree size;
727 {
731 }
733 {
737 }
741 {
744 }
745 else
746 /* Convert in case a char is more than one unit. */
751 /* SIZE will have an integer type with TYPE_IS_SIZETYPE set.
752 TYPE_IS_SIZETYPE means that certain things (like overflow) will
753 never happen. However, this node should really have type
754 `size_t', which is just a typedef for an ordinary integer type. */
756 }
758 tree
760 tree type;
761 {
763 tree size;
769 else
770 /* Convert in case a char is more than one unit. */
775 /* SIZE will have an integer type with TYPE_IS_SIZETYPE set.
776 TYPE_IS_SIZETYPE means that certain things (like overflow) will
777 never happen. However, this node should really have type
778 `size_t', which is just a typedef for an ordinary integer type. */
780 }
782 /* Compute the size to increment a pointer by. */
784 tree
786 tree type;
787 {
794 {
797 }
799 /* Convert in case a char is more than one unit. */
803 }
804 \f
805 /* Return either DECL or its known constant value (if it has one). */
807 tree
809 tree decl;
810 {
812 in a place where a variable is invalid. */
818 /* This is invalid if initial value is not constant.
819 If it has either a function call, a memory reference,
820 or a variable, then re-evaluating it could give different results. */
822 /* Check for cases where this is sub-optimal, even though valid. */
826 }
828 /* Return either DECL or its known constant value (if it has one), but
829 return DECL if pedantic or DECL has mode BLKmode. This is for
830 bug-compatibility with the old behavior of decl_constant_value
831 (before GCC 3.0); every use of this function is a bug and it should
832 be removed before GCC 3.1. It is not appropriate to use pedantic
833 in a way that affects optimization, and BLKmode is probably not the
834 right test for avoiding misoptimizations either. */
836 static tree
838 tree decl;
839 {
842 else
844 }
847 /* Perform the default conversion of arrays and functions to pointers.
848 Return the result of converting EXP. For any other expression, just
849 return EXP. */
851 static tree
853 tree exp;
854 {
855 tree orig_exp;
860 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
861 an lvalue.
863 Do not use STRIP_NOPS here! It will remove conversions from pointer
864 to integer and cause infinite recursion. */
869 {
873 }
875 /* Preserve the original expression code. */
880 {
882 }
884 {
885 tree adr;
887 tree ptrtype;
893 {
896 }
899 restype
910 {
914 }
918 {
919 /* Before C99, non-lvalue arrays do not decay to pointers.
920 Normally, using such an array would be invalid; but it can
921 be used correctly inside sizeof or as a statement expression.
922 Thus, do not give an error here; an error will result later. */
924 }
929 {
930 /* ??? This is not really quite correct
931 in that the type of the operand of ADDR_EXPR
932 is not the target type of the type of the ADDR_EXPR itself.
933 Question is, can this lossage be avoided? */
940 }
941 /* This way is better for a COMPONENT_REF since it can
942 simplify the offset for a component. */
945 }
947 }
949 /* Perform default promotions for C data used in expressions.
950 Arrays and functions are converted to pointers;
951 enumeral types or short or char, to int.
952 In addition, manifest constants symbols are replaced by their values. */
954 tree
956 tree exp;
957 {
958 tree orig_exp;
965 /* Constants can be used directly unless they're not loadable. */
969 /* Replace a nonvolatile const static variable with its value unless
970 it is an array, in which case we must be sure that taking the
971 address of the array produces consistent results. */
973 {
976 }
978 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
979 an lvalue.
981 Do not use STRIP_NOPS here! It will remove conversions from pointer
982 to integer and cause infinite recursion. */
989 /* Preserve the original expression code. */
993 /* Normally convert enums to int,
994 but convert wide enums to something wider. */
996 {
999 ((flag_traditional
1005 }
1009 /* If it's thinner than an int, promote it like a
1010 c_promoting_integer_type_p, otherwise leave it alone. */
1015 exp);
1018 {
1019 /* Traditionally, unsignedness is preserved in default promotions.
1020 Also preserve unsignedness if not really getting any wider. */
1022 && (flag_traditional
1027 }
1034 {
1037 }
1039 }
1040 \f
1041 /* Look up COMPONENT in a structure or union DECL.
1043 If the component name is not found, returns NULL_TREE. Otherwise,
1044 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1045 stepping down the chain to the component, which is in the last
1046 TREE_VALUE of the list. Normally the list is of length one, but if
1047 the component is embedded within (nested) anonymous structures or
1048 unions, the list steps down the chain to the component. */
1050 static tree
1053 {
1055 tree field;
1057 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1058 to the field elements. Use a binary search on this array to quickly
1059 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1060 will always be set for structures which have many elements. */
1063 {
1071 {
1076 {
1077 /* Step through all anon unions in linear fashion. */
1079 {
1083 {
1088 }
1089 }
1091 /* Entire record is only anon unions. */
1095 /* Restart the binary search, with new lower bound. */
1097 }
1103 else
1105 }
1111 }
1112 else
1113 {
1115 {
1119 {
1124 }
1128 }
1132 }
1135 }
1137 /* Make an expression to refer to the COMPONENT field of
1138 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1140 tree
1143 {
1147 tree ref;
1149 /* If DATUM is a COMPOUND_EXPR, move our reference inside it.
1150 If pedantic ensure that the arguments are not lvalues; otherwise,
1151 if the component is an array, it would wrongly decay to a pointer in
1152 C89 mode.
1153 We cannot do this with a COND_EXPR, because in a conditional expression
1154 the default promotions are applied to both sides, and this would yield
1155 the wrong type of the result; for example, if the components have
1156 type "char". */
1158 {
1160 {
1164 }
1167 }
1169 /* See if there is a field or component with name COMPONENT. */
1172 {
1174 {
1177 }
1182 {
1187 }
1189 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1190 This might be better solved in future the way the C++ front
1191 end does it - by giving the anonymous entities each a
1192 separate name and type, and then have build_component_ref
1193 recursively call itself. We can't do that here. */
1195 {
1211 }
1214 }
1220 }
1221 \f
1222 /* Given an expression PTR for a pointer, return an expression
1223 for the value pointed to.
1224 ERRORSTRING is the name of the operator to appear in error messages. */
1226 tree
1228 tree ptr;
1230 {
1235 {
1237 && !flag_volatile
1241 else
1242 {
1247 {
1250 }
1254 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1255 so that we get the proper error message if the result is used
1256 to assign to. Also, &* is supposed to be a no-op.
1257 And ANSI C seems to specify that the type of the result
1258 should be the const type. */
1259 /* A de-reference of a pointer to const is not a const. It is valid
1260 to change it via some other pointer. */
1266 }
1267 }
1271 }
1273 /* This handles expressions of the form "a[i]", which denotes
1274 an array reference.
1276 This is logically equivalent in C to *(a+i), but we may do it differently.
1277 If A is a variable or a member, we generate a primitive ARRAY_REF.
1278 This avoids forcing the array out of registers, and can work on
1279 arrays that are not lvalues (for example, members of structures returned
1280 by functions). */
1282 tree
1285 {
1287 {
1290 }
1298 {
1301 /* Subscripting with type char is likely to lose
1302 on a machine where chars are signed.
1303 So warn on any machine, but optionally.
1304 Don't warn for unsigned char since that type is safe.
1305 Don't warn for signed char because anyone who uses that
1306 must have done so deliberately. */
1311 /* Apply default promotions *after* noticing character types. */
1314 /* Require integer *after* promotion, for sake of enums. */
1316 {
1319 }
1321 /* An array that is indexed by a non-constant
1322 cannot be stored in a register; we must be able to do
1323 address arithmetic on its address.
1324 Likewise an array of elements of variable size. */
1328 {
1331 }
1332 /* An array that is indexed by a constant value which is not within
1333 the array bounds cannot be stored in a register either; because we
1334 would get a crash in store_bit_field/extract_bit_field when trying
1335 to access a non-existent part of the register. */
1339 {
1342 }
1345 {
1353 }
1357 /* Array ref is const/volatile if the array elements are
1358 or if the array is. */
1367 /* This was added by rms on 16 Nov 91.
1368 It fixes vol struct foo *a; a->elts[1]
1369 in an inline function.
1370 Hope it doesn't break something else. */
1373 }
1375 {
1379 /* Do the same warning check as above, but only on the part that's
1380 syntactically the index and only if it is also semantically
1381 the index. */
1387 /* Put the integer in IND to simplify error checking. */
1389 {
1393 }
1400 {
1403 }
1405 {
1408 }
1412 }
1413 }
1414 \f
1415 /* Build an external reference to identifier ID. FUN indicates
1416 whether this will be used for a function call. */
1417 tree
1419 tree id;
1421 {
1422 tree ref;
1430 {
1434 {
1436 /* Ordinary implicit function declaration. */
1438 else
1439 {
1440 /* Implicit declaration of built-in function. Don't
1441 change the built-in declaration, but don't let this
1442 go by silently, either. */
1445 /* only issue this warning once */
1448 }
1449 }
1450 else
1451 {
1452 /* Reference to undeclared variable, including reference to
1453 builtin outside of function-call context. */
1457 else
1458 {
1461 {
1466 {
1470 }
1471 }
1474 }
1476 }
1477 }
1478 else
1479 {
1480 /* Properly declared variable or function reference. */
1484 {
1488 }
1489 else
1491 }
1500 {
1503 }
1506 }
1508 /* Build a function call to function FUNCTION with parameters PARAMS.
1509 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1510 TREE_VALUE of each node is a parameter-expression.
1511 FUNCTION's data type may be a function type or a pointer-to-function. */
1513 tree
1516 {
1518 tree coerced_params;
1521 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1524 /* Convert anything with function type to a pointer-to-function. */
1526 {
1530 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1531 (because calling an inline function does not mean the function
1532 needs to be separately compiled). */
1538 }
1539 else
1549 {
1552 }
1557 /* fntype now gets the type of function pointed to. */
1560 /* Convert the parameters to the types declared in the
1561 function prototype, or apply default promotions. */
1563 coerced_params
1566 /* Check for errors in format strings. */
1571 /* Recognize certain built-in functions so we can make tree-codes
1572 other than CALL_EXPR. We do this when it enables fold-const.c
1573 to do something useful. */
1578 {
1583 }
1593 }
1594 \f
1595 /* Convert the argument expressions in the list VALUES
1596 to the types in the list TYPELIST. The result is a list of converted
1597 argument expressions.
1599 If TYPELIST is exhausted, or when an element has NULL as its type,
1600 perform the default conversions.
1602 PARMLIST is the chain of parm decls for the function being called.
1603 It may be 0, if that info is not available.
1604 It is used only for generating error messages.
1606 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1608 This is also where warnings about wrong number of args are generated.
1610 Both VALUES and the returned value are chains of TREE_LIST nodes
1611 with the elements of the list in the TREE_VALUE slots of those nodes. */
1613 static tree
1616 {
1621 /* Scan the given expressions and types, producing individual
1622 converted arguments and pushing them on RESULT in reverse order. */
1625 valtail;
1627 {
1632 {
1636 else
1639 }
1641 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1642 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1643 to convert automatically to a pointer. */
1652 {
1653 /* Formal parm type is specified by a function prototype. */
1654 tree parmval;
1657 {
1660 }
1661 else
1662 {
1663 /* Optionally warn about conversions that
1664 differ from the default conversions. */
1666 {
1671 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1674 warn_for_assignment ("%s as integer rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1677 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1680 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1683 warn_for_assignment ("%s as complex rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1686 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1687 /* ??? At some point, messages should be written about
1688 conversions between complex types, but that's too messy
1689 to do now. */
1692 {
1693 /* Warn if any argument is passed as `float',
1694 since without a prototype it would be `double'. */
1696 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1697 }
1698 /* Detect integer changing in width or signedness.
1699 These warnings are only activated with
1700 -Wconversion, not with -Wtraditional. */
1703 {
1710 /* No warning if function asks for enum
1711 and the actual arg is that enum type. */
1712 ;
1714 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1716 ;
1717 /* Don't complain if the formal parameter type
1718 is an enum, because we can't tell now whether
1719 the value was an enum--even the same enum. */
1721 ;
1724 /* Change in signedness doesn't matter
1725 if a constant value is unaffected. */
1726 ;
1727 /* Likewise for a constant in a NOP_EXPR. */
1731 ;
1736 /* Change in signedness doesn't matter
1737 if an enum value is unaffected. */
1738 ;
1739 #endif
1740 /* If the value is extended from a narrower
1741 unsigned type, it doesn't matter whether we
1742 pass it as signed or unsigned; the value
1743 certainly is the same either way. */
1746 ;
1749 else
1751 }
1752 }
1762 }
1764 }
1768 /* Convert `float' to `double'. */
1770 else
1771 /* Convert `short' and `char' to full-size `int'. */
1776 }
1779 {
1783 else
1785 }
1788 }
1789 \f
1790 /* This is the entry point used by the parser
1791 for binary operators in the input.
1792 In addition to constructing the expression,
1793 we check for operands that were written with other binary operators
1794 in a way that is likely to confuse the user. */
1796 tree
1800 {
1817 /* Check for cases such as x+y<<z which users are likely
1818 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1819 is cleared to prevent these warnings. */
1821 {
1823 {
1827 }
1830 {
1834 }
1837 {
1843 /* Check cases like x|y==z */
1846 }
1849 {
1855 /* Check cases like x^y==z */
1858 }
1861 {
1865 /* Check cases like x&y==z */
1868 }
1869 }
1871 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1882 /* Record the code that was specified in the source,
1883 for the sake of warnings about confusing nesting. */
1886 else
1887 {
1889 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1890 so that convert_for_assignment wouldn't strip it.
1891 That way, we got warnings for things like p = (1 - 1).
1892 But it turns out we should not get those warnings. */
1896 }
1899 }
1901 /* Build a binary-operation expression without default conversions.
1902 CODE is the kind of expression to build.
1903 This function differs from `build' in several ways:
1904 the data type of the result is computed and recorded in it,
1905 warnings are generated if arg data types are invalid,
1906 special handling for addition and subtraction of pointers is known,
1907 and some optimization is done (operations on narrow ints
1908 are done in the narrower type when that gives the same result).
1909 Constant folding is also done before the result is returned.
1911 Note that the operands will never have enumeral types, or function
1912 or array types, because either they will have the default conversions
1913 performed or they have both just been converted to some other type in which
1914 the arithmetic is to be done. */
1916 tree
1921 {
1926 /* Expression code to give to the expression when it is built.
1927 Normally this is CODE, which is what the caller asked for,
1928 but in some special cases we change it. */
1931 /* Data type in which the computation is to be performed.
1932 In the simplest cases this is the common type of the arguments. */
1935 /* Nonzero means operands have already been type-converted
1936 in whatever way is necessary.
1937 Zero means they need to be converted to RESULT_TYPE. */
1940 /* Nonzero means create the expression with this type, rather than
1941 RESULT_TYPE. */
1944 /* Nonzero means after finally constructing the expression
1945 convert it to this type. */
1948 /* Nonzero if this is an operation like MIN or MAX which can
1949 safely be computed in short if both args are promoted shorts.
1950 Also implies COMMON.
1951 -1 indicates a bitwise operation; this makes a difference
1952 in the exact conditions for when it is safe to do the operation
1953 in a narrower mode. */
1956 /* Nonzero if this is a comparison operation;
1957 if both args are promoted shorts, compare the original shorts.
1958 Also implies COMMON. */
1961 /* Nonzero if this is a right-shift operation, which can be computed on the
1962 original short and then promoted if the operand is a promoted short. */
1965 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1969 {
1972 }
1973 else
1974 {
1977 }
1982 /* The expression codes of the data types of the arguments tell us
1983 whether the arguments are integers, floating, pointers, etc. */
1987 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1991 /* If an error was already reported for one of the arguments,
1992 avoid reporting another error. */
1998 {
2000 /* Handle the pointer + int case. */
2005 else
2010 /* Subtraction of two similar pointers.
2011 We must subtract them as integers, then divide by object size. */
2015 /* Handle pointer minus int. Just like pointer plus int. */
2018 else
2031 /* Floating point division by zero is a legitimate way to obtain
2032 infinities and NaNs. */
2040 {
2043 else
2044 /* Although it would be tempting to shorten always here, that
2045 loses on some targets, since the modulo instruction is
2046 undefined if the quotient can't be represented in the
2047 computation mode. We shorten only if unsigned or if
2048 dividing by something we know != -1. */
2053 }
2070 {
2071 /* Although it would be tempting to shorten always here, that loses
2072 on some targets, since the modulo instruction is undefined if the
2073 quotient can't be represented in the computation mode. We shorten
2074 only if unsigned or if dividing by something we know != -1. */
2079 }
2091 {
2092 /* Result of these operations is always an int,
2093 but that does not mean the operands should be
2094 converted to ints! */
2099 }
2102 /* Shift operations: result has same type as first operand;
2103 always convert second operand to int.
2104 Also set SHORT_SHIFT if shifting rightward. */
2108 {
2110 {
2113 else
2114 {
2120 }
2121 }
2123 /* Use the type of the value to be shifted.
2124 This is what most traditional C compilers do. */
2126 /* Unless traditional, convert the shift-count to an integer,
2127 regardless of size of value being shifted. */
2129 {
2132 /* Avoid converting op1 to result_type later. */
2134 }
2135 }
2140 {
2142 {
2148 }
2150 /* Use the type of the value to be shifted.
2151 This is what most traditional C compilers do. */
2153 /* Unless traditional, convert the shift-count to an integer,
2154 regardless of size of value being shifted. */
2156 {
2159 /* Avoid converting op1 to result_type later. */
2161 }
2162 }
2168 {
2170 {
2175 }
2177 /* Use the type of the value to be shifted.
2178 This is what most traditional C compilers do. */
2180 /* Unless traditional, convert the shift-count to an integer,
2181 regardless of size of value being shifted. */
2183 {
2186 /* Avoid converting op1 to result_type later. */
2188 }
2189 }
2196 /* Result of comparison is always int,
2197 but don't convert the args to int! */
2205 {
2208 /* Anything compares with void *. void * compares with anything.
2209 Otherwise, the targets must be compatible
2210 and both must be object or both incomplete. */
2214 {
2215 /* op0 != orig_op0 detects the case of something
2216 whose value is 0 but which isn't a valid null ptr const. */
2220 }
2222 {
2226 }
2227 else
2232 }
2240 {
2244 }
2246 {
2250 }
2259 {
2261 {
2266 }
2267 else
2268 {
2271 }
2272 }
2284 {
2286 {
2294 }
2295 else
2296 {
2299 }
2300 }
2303 {
2307 }
2310 {
2314 }
2316 {
2320 }
2322 {
2326 }
2338 {
2341 }
2347 }
2350 &&
2352 {
2358 /* For certain operations (which identify themselves by shorten != 0)
2359 if both args were extended from the same smaller type,
2360 do the arithmetic in that type and then extend.
2362 shorten !=0 and !=1 indicates a bitwise operation.
2363 For them, this optimization is safe only if
2364 both args are zero-extended or both are sign-extended.
2365 Otherwise, we might change the result.
2366 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2367 but calculated in (unsigned short) it would be (unsigned short)-1. */
2370 {
2374 /* UNS is 1 if the operation to be done is an unsigned one. */
2376 tree type;
2380 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2381 but it *requires* conversion to FINAL_TYPE. */
2392 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2394 /* For bitwise operations, signedness of nominal type
2395 does not matter. Consider only how operands were extended. */
2399 /* Note that in all three cases below we refrain from optimizing
2400 an unsigned operation on sign-extended args.
2401 That would not be valid. */
2403 /* Both args variable: if both extended in same way
2404 from same width, do it in that width.
2405 Do it unsigned if args were zero-extended. */
2412 result_type
2431 }
2433 /* Shifts can be shortened if shifting right. */
2436 {
2446 /* We can shorten only if the shift count is less than the
2447 number of bits in the smaller type size. */
2449 /* We cannot drop an unsigned shift after sign-extension. */
2451 {
2452 /* Do an unsigned shift if the operand was zero-extended. */
2453 result_type
2455 /* Convert value-to-be-shifted to that type. */
2459 }
2460 }
2462 /* Comparison operations are shortened too but differently.
2463 They identify themselves by setting short_compare = 1. */
2466 {
2467 /* Don't write &op0, etc., because that would prevent op0
2468 from being kept in a register.
2469 Instead, make copies of the our local variables and
2470 pass the copies by reference, then copy them back afterward. */
2473 tree val
2485 {
2497 /* Give warnings for comparisons between signed and unsigned
2498 quantities that may fail.
2500 Do the checking based on the original operand trees, so that
2501 casts will be considered, but default promotions won't be.
2503 Do not warn if the comparison is being done in a signed type,
2504 since the signed type will only be chosen if it can represent
2505 all the values of the unsigned type. */
2508 /* Do not warn if both operands are the same signedness. */
2511 else
2512 {
2517 else
2520 /* Do not warn if the signed quantity is an
2521 unsuffixed integer literal (or some static
2522 constant expression involving such literals or a
2523 conditional expression involving such literals)
2524 and it is non-negative. */
2527 /* Do not warn if the comparison is an equality operation,
2528 the unsigned quantity is an integral constant, and it
2529 would fit in the result if the result were signed. */
2534 /* Do not warn if the unsigned quantity is an enumeration
2535 constant and its maximum value would fit in the result
2536 if the result were signed. */
2542 else
2544 }
2546 /* Warn if two unsigned values are being compared in a size
2547 larger than their original size, and one (and only one) is the
2548 result of a `~' operator. This comparison will always fail.
2550 Also warn if one operand is a constant, and the constant
2551 does not have all bits set that are set in the ~ operand
2552 when it is extended. */
2556 {
2560 else
2565 {
2566 tree primop;
2571 {
2575 }
2576 else
2577 {
2581 }
2586 {
2590 }
2591 }
2598 }
2599 }
2600 }
2601 }
2603 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2604 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2605 Then the expression will be built.
2606 It will be given type FINAL_TYPE if that is nonzero;
2607 otherwise, it will be given type RESULT_TYPE. */
2610 {
2613 }
2616 {
2621 }
2626 {
2628 tree folded;
2636 }
2637 }
2638 \f
2639 /* Return a tree for the difference of pointers OP0 and OP1.
2640 The resulting tree has type int. */
2642 static tree
2645 {
2654 {
2659 }
2661 /* If the conversion to ptrdiff_type does anything like widening or
2662 converting a partial to an integral mode, we get a convert_expression
2663 that is in the way to do any simplifications.
2664 (fold-const.c doesn't know that the extra bits won't be needed.
2665 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2666 different mode in place.)
2667 So first try to find a common term here 'by hand'; we want to cover
2668 at least the cases that occur in legal static initializers. */
2673 {
2676 }
2677 else
2681 {
2684 }
2685 else
2689 {
2692 }
2695 /* First do the subtraction as integers;
2696 then drop through to build the divide operator.
2697 Do not do default conversions on the minus operator
2698 in case restype is a short type. */
2702 /* This generates an error if op1 is pointer to incomplete type. */
2706 /* This generates an error if op0 is pointer to incomplete type. */
2709 /* Divide by the size, in easiest possible way. */
2717 }
2718 \f
2719 /* Construct and perhaps optimize a tree representation
2720 for a unary operation. CODE, a tree_code, specifies the operation
2721 and XARG is the operand.
2722 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2723 the default promotions (such as from short to int).
2724 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2725 allows non-lvalues; this is only used to handle conversion of non-lvalue
2726 arrays to pointers in C99. */
2728 tree
2731 tree xarg;
2733 {
2734 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2738 tree val;
2747 {
2749 /* This is used for unary plus, because a CONVERT_EXPR
2750 is enough to prevent anybody from looking inside for
2751 associativity, but won't generate any code. */
2754 {
2757 }
2765 {
2768 }
2775 {
2781 }
2783 {
2786 }
2794 {
2797 }
2803 /* Conjugating a real value is a no-op, but allow it anyway. */
2806 {
2809 }
2818 /* These will convert to a pointer. */
2820 {
2823 }
2835 else
2843 else
2850 /* Handle complex lvalues (when permitted)
2851 by reduction to simpler cases. */
2857 /* Increment or decrement the real part of the value,
2858 and don't change the imaginary part. */
2860 {
2871 }
2873 /* Report invalid types. */
2877 {
2880 else
2884 }
2886 {
2887 tree inc;
2893 /* Compute the increment. */
2896 {
2897 /* If pointer target is an undefined struct,
2898 we just cannot know how to do the arithmetic. */
2900 {
2903 else
2905 }
2909 {
2912 else
2914 }
2917 }
2918 else
2923 /* Handle incrementing a cast-expression. */
2927 {
2936 /* If the real type has the same machine representation
2937 as the type it is cast to, we can make better output
2938 by adding directly to the inside of the cast. */
2944 else
2945 {
2949 else
2950 {
2954 else
2963 }
2966 }
2971 }
2972 give_up:
2974 /* Complain about anything else that is not a true lvalue. */
2981 /* Report a read-only lvalue. */
2990 else
2997 }
3000 /* Note that this operation never does default_conversion. */
3002 /* Let &* cancel out to simplify resulting code. */
3004 {
3005 /* Don't let this be an lvalue. */
3009 }
3011 /* For &x[y], return x+y */
3013 {
3018 }
3020 /* Handle complex lvalues (when permitted)
3021 by reduction to simpler cases. */
3027 float f; *&(int)f = 3.4 stores in int format
3028 whereas (int)f = 3.4 stores in float format. */
3029 /* Address of a cast is just a cast of the address
3030 of the operand of the cast. */
3032 {
3045 }
3046 #endif
3048 /* Anything not already handled and not a true memory reference
3049 or a non-lvalue array is an error. */
3054 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3057 /* If the lvalue is const or volatile, merge that into the type
3058 to which the address will point. Note that you can't get a
3059 restricted pointer by taking the address of something, so we
3060 only have to deal with `const' and `volatile' here. */
3072 {
3073 tree addr;
3076 {
3082 {
3086 }
3091 }
3092 else
3095 /* Address of a static or external variable or
3096 file-scope function counts as a constant. */
3102 }
3106 }
3111 }
3113 #if 0
3114 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3115 convert ARG with the same conversions in the same order
3116 and return the result. */
3118 static tree
3120 tree conversions;
3121 tree arg;
3122 {
3124 {
3134 arg));
3138 }
3139 }
3142 /* Return nonzero if REF is an lvalue valid for this language.
3143 Lvalues can be assigned, unless their type has TYPE_READONLY.
3144 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3146 int
3148 tree ref;
3149 {
3153 {
3178 }
3179 }
3181 /* Return nonzero if REF is an lvalue valid for this language;
3182 otherwise, print an error message and return zero. */
3184 int
3186 tree ref;
3188 {
3195 }
3197 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3198 for certain kinds of expressions which are not really lvalues
3199 but which we can accept as lvalues. If FLAG is nonzero, then
3200 non-lvalues are OK since we may be converting a non-lvalue array to
3201 a pointer in C99.
3203 If ARG is not a kind of expression we can handle, return zero. */
3205 static tree
3208 tree arg;
3210 {
3211 /* Handle (a, b) used as an "lvalue". */
3213 {
3216 /* If this returns a function type, it isn't really being used as
3217 an lvalue, so don't issue a warning about it. */
3223 }
3225 /* Handle (a ? b : c) used as an "lvalue". */
3227 {
3237 }
3240 }
3242 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3243 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3245 static void
3248 {
3251 {
3261 }
3262 }
3263 \f
3264 /* Warn about storing in something that is `const'. */
3266 void
3268 tree arg;
3270 {
3272 {
3275 else
3278 }
3282 else
3284 }
3285 \f
3286 /* Mark EXP saying that we need to be able to take the
3287 address of it; it should not be allocated in a register.
3288 Value is 1 if successful. */
3290 int
3292 tree exp;
3293 {
3297 {
3300 {
3304 }
3306 /* ... fall through ... */
3326 {
3328 {
3332 }
3335 }
3337 {
3339 {
3343 }
3345 /* If we are making this addressable due to its having
3346 volatile components, give a different error message. Also
3347 handle the case of an unnamed parameter by not trying
3348 to give the name. */
3351 {
3354 }
3358 }
3361 /* drops in */
3367 #endif
3371 }
3372 }
3373 \f
3374 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3376 tree
3379 {
3380 tree type1;
3381 tree type2;
3390 /* Don't promote the operands separately if they promote
3391 the same way. Return the unpromoted type and let the combined
3392 value get promoted if necessary. */
3398 {
3403 }
3404 #endif
3406 /* Promote both alternatives. */
3423 /* Quickly detect the usual case where op1 and op2 have the same type
3424 after promotion. */
3426 {
3429 else
3431 }
3436 {
3439 /* If -Wsign-compare, warn here if type1 and type2 have
3440 different signedness. We'll promote the signed to unsigned
3441 and later code won't know it used to be different.
3442 Do this check on the original types, so that explicit casts
3443 will be considered, but default promotions won't. */
3446 {
3451 {
3452 /* Do not warn if the result type is signed, since the
3453 signed type will only be chosen if it can represent
3454 all the values of the unsigned type. */
3457 /* Do not warn if the signed quantity is an unsuffixed
3458 integer literal (or some static constant expression
3459 involving such literals) and it is non-negative. */
3463 else
3465 }
3466 }
3467 }
3469 {
3473 }
3475 {
3485 {
3490 }
3492 {
3497 }
3498 else
3499 {
3502 }
3503 }
3505 {
3508 else
3509 {
3511 }
3513 }
3515 {
3518 else
3519 {
3521 }
3523 }
3526 {
3529 else
3530 {
3533 }
3534 }
3536 /* Merge const and volatile flags of the incoming types. */
3537 result_type
3551 }
3552 \f
3553 /* Given a list of expressions, return a compound expression
3554 that performs them all and returns the value of the last of them. */
3556 tree
3558 tree list;
3559 {
3561 }
3563 static tree
3565 tree list;
3567 {
3568 tree rest;
3571 {
3572 /* Convert arrays and functions to pointers when there
3573 really is a comma operator. */
3579 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3581 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3584 #endif
3586 /* Don't let (0, 0) be null pointer constant. */
3590 }
3595 {
3596 /* The left-hand operand of a comma expression is like an expression
3597 statement: with -W or -Wunused, we should warn if it doesn't have
3598 any side-effects, unless it was explicitly cast to (void). */
3604 /* When pedantic, a compound expression can be neither an lvalue
3605 nor an integer constant expression. */
3608 }
3610 /* With -Wunused, we should also warn if the left-hand operand does have
3611 side-effects, but computes a value which is not used. For example, in
3612 `foo() + bar(), baz()' the result of the `+' operator is not used,
3613 so we should issue a warning. */
3618 }
3620 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3622 tree
3624 tree type;
3625 tree expr;
3626 {
3633 #if 0
3634 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3637 #endif
3640 {
3643 }
3646 {
3649 }
3652 {
3654 {
3658 }
3659 }
3661 {
3662 tree field;
3671 {
3673 tree t;
3678 {
3681 else
3683 }
3684 else
3691 }
3694 }
3695 else
3696 {
3699 /* If casting to void, avoid the error that would come
3700 from default_conversion in the case of a non-lvalue array. */
3704 /* Convert functions and arrays to pointers,
3705 but don't convert any other types. */
3709 /* Optionally warn about potentially worrisome casts. */
3714 {
3720 /* Check that the qualifiers on IN_TYPE are a superset of
3721 the qualifiers of IN_OTYPE. The outermost level of
3722 POINTER_TYPE nodes is uninteresting and we stop as soon
3723 as we hit a non-POINTER_TYPE node on either type. */
3724 do
3725 {
3729 /* GNU C allows cv-qualified function types. 'const'
3730 means the function is very pure, 'volatile' means it
3731 can't return. We need to warn when such qualifiers
3732 are added, not when they're taken away. */
3736 else
3738 }
3746 /* There are qualifiers present in IN_OTYPE that are not
3747 present in IN_TYPE. */
3749 }
3751 /* Warn about possible alignment problems. */
3757 /* Don't warn about opaque types, where the actual alignment
3758 restriction is unknown. */
3779 /* Don't warn about converting any constant. */
3786 /* Ignore any integer overflow caused by the cast. */
3788 {
3791 }
3792 }
3794 /* Pedantically, don't let (void *) (FOO *) 0 be a null pointer constant. */
3800 /* If pedantic, don't let a cast be an lvalue. */
3805 }
3807 /* Interpret a cast of expression EXPR to type TYPE. */
3808 tree
3811 {
3814 /* This avoids warnings about unprototyped casts on
3815 integers. E.g. "#define SIG_DFL (void(*)())0". */
3822 }
3824 \f
3825 /* Build an assignment expression of lvalue LHS from value RHS.
3826 MODIFYCODE is the code for a binary operator that we use
3827 to combine the old value of LHS with RHS to get the new value.
3828 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3830 tree
3834 {
3835 tree result;
3836 tree newrhs;
3840 /* Types that aren't fully specified cannot be used in assignments. */
3843 /* Avoid duplicate error messages from operands that had errors. */
3847 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3848 /* Do not use STRIP_NOPS here. We do not want an enumerator
3849 whose value is 0 to count as a null pointer constant. */
3855 /* Handle control structure constructs used as "lvalues". */
3858 {
3859 /* Handle (a, b) used as an "lvalue". */
3868 /* Handle (a ? b : c) used as an "lvalue". */
3872 {
3873 /* Produce (a ? (b = rhs) : (c = rhs))
3874 except that the RHS goes through a save-expr
3875 so the code to compute it is only emitted once. */
3876 tree cond
3884 /* Make sure the code to compute the rhs comes out
3885 before the split. */
3887 /* But cast it to void to avoid an "unused" error. */
3889 }
3892 }
3894 /* If a binary op has been requested, combine the old LHS value with the RHS
3895 producing the value we should actually store into the LHS. */
3898 {
3901 }
3903 /* Handle a cast used as an "lvalue".
3904 We have already performed any binary operator using the value as cast.
3905 Now convert the result to the cast type of the lhs,
3906 and then true type of the lhs and store it there;
3907 then convert result back to the cast type to be the value
3908 of the assignment. */
3911 {
3920 {
3922 tree result;
3930 }
3934 }
3936 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3937 Reject anything strange now. */
3942 /* Warn about storing in something that is `const'. */
3950 /* If storing into a structure or union member,
3951 it has probably been given type `int'.
3952 Compute the type that would go with
3953 the actual amount of storage the member occupies. */
3962 /* If storing in a field that is in actuality a short or narrower than one,
3963 we must store in the field in its actual type. */
3966 {
3969 }
3971 /* Convert new value to destination type. */
3978 /* Scan operands */
3983 /* If we got the LHS in a different type for storing in,
3984 convert the result back to the nominal type of LHS
3985 so that the value we return always has the same type
3986 as the LHS argument. */
3992 }
3993 \f
3994 /* Convert value RHS to type TYPE as preparation for an assignment
3995 to an lvalue of type TYPE.
3996 The real work of conversion is done by `convert'.
3997 The purpose of this function is to generate error messages
3998 for assignments that are not allowed in C.
3999 ERRTYPE is a string to use in error messages:
4000 "assignment", "return", etc. If it is null, this is parameter passing
4001 for a function call (and different error messages are output).
4003 FUNNAME is the name of the function being called,
4004 as an IDENTIFIER_NODE, or null.
4005 PARMNUM is the number of the argument, for printing in error messages. */
4007 static tree
4013 {
4015 tree rhstype;
4018 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4019 /* Do not use STRIP_NOPS here. We do not want an enumerator
4020 whose value is 0 to count as a null pointer constant. */
4037 {
4039 /* Check for Objective-C protocols. This will issue a warning if
4040 there are protocol violations. No need to use the return value. */
4043 }
4046 {
4049 }
4050 /* A type converts to a reference to it.
4051 This code doesn't fully support references, it's just for the
4052 special case of va_start and va_copy. */
4055 {
4060 /* We already know that these two types are compatible, but they
4061 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4062 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4063 likely to be va_list, a typedef to __builtin_va_list, which
4064 is different enough that it will cause problems later. */
4070 }
4071 /* Arithmetic types all interconvert, and enum is treated like int. */
4080 /* Conversion to a transparent union from its member types.
4081 This applies only to function arguments. */
4083 {
4084 tree memb_types;
4089 {
4100 {
4104 /* Any non-function converts to a [const][volatile] void *
4105 and vice versa; otherwise, targets must be the same.
4106 Meanwhile, the lhs target must have all the qualifiers of
4107 the rhs. */
4110 {
4111 /* If this type won't generate any warnings, use it. */
4121 /* Keep looking for a better type, but remember this one. */
4124 }
4125 }
4127 /* Can convert integer zero to any pointer type. */
4131 {
4134 }
4135 }
4138 {
4140 {
4141 /* We have only a marginally acceptable member type;
4142 it needs a warning. */
4146 /* Const and volatile mean something different for function
4147 types, so the usual warnings are not appropriate. */
4150 {
4151 /* Because const and volatile on functions are
4152 restrictions that say the function will not do
4153 certain things, it is okay to use a const or volatile
4154 function where an ordinary one is wanted, but not
4155 vice-versa. */
4159 }
4163 parmnum);
4164 }
4170 }
4171 }
4173 /* Conversions among pointers */
4176 {
4180 /* Any non-function converts to a [const][volatile] void *
4181 and vice versa; otherwise, targets must be the same.
4182 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4187 {
4190 ||
4192 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4193 which are not ANSI null ptr constants. */
4198 /* Const and volatile mean something different for function types,
4199 so the usual warnings are not appropriate. */
4202 {
4206 /* If this is not a case of ignoring a mismatch in signedness,
4207 no warning. */
4210 ;
4211 /* If there is a mismatch, do warn. */
4215 }
4218 {
4219 /* Because const and volatile on functions are restrictions
4220 that say the function will not do certain things,
4221 it is okay to use a const or volatile function
4222 where an ordinary one is wanted, but not vice-versa. */
4226 }
4227 }
4228 else
4232 }
4234 {
4235 /* An explicit constant 0 can convert to a pointer,
4236 or one that results from arithmetic, even including
4237 a cast to integer type. */
4239 &&
4244 {
4248 }
4250 }
4252 {
4256 }
4261 {
4263 {
4269 else
4272 }
4273 else
4275 parmnum);
4276 }
4277 else
4281 }
4283 /* Convert VALUE for assignment into inlined parameter PARM. */
4285 tree
4288 {
4291 /* If FN was prototyped, the value has been converted already
4292 in convert_arguments. */
4305 }
4307 /* Print a warning using MSGID.
4308 It gets OPNAME as its one parameter.
4309 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4310 FUNCTION and ARGNUM are handled specially if we are building an
4311 Objective-C selector. */
4313 static void
4317 tree function;
4319 {
4321 {
4326 {
4329 }
4331 {
4332 /* Function name is known; supply it. */
4339 }
4340 else
4341 {
4342 /* Function name unknown (call through ptr); just give arg number. */
4346 }
4348 }
4350 }
4351 \f
4352 /* If VALUE is a compound expr all of whose expressions are constant, then
4353 return its value. Otherwise, return error_mark_node.
4355 This is for handling COMPOUND_EXPRs as initializer elements
4356 which is allowed with a warning when -pedantic is specified. */
4358 static tree
4360 tree value;
4361 tree endtype;
4362 {
4364 {
4369 endtype);
4370 }
4374 else
4376 }
4377 \f
4378 /* Perform appropriate conversions on the initial value of a variable,
4379 store it in the declaration DECL,
4380 and print any error messages that are appropriate.
4381 If the init is invalid, store an ERROR_MARK. */
4383 void
4386 {
4389 /* If variable's type was invalidly declared, just ignore it. */
4395 /* Digest the specified initializer into an expression. */
4400 /* Store the expression if valid; else report error. */
4402 #if 0
4403 /* Note that this is the only place we can detect the error
4404 in a case such as struct foo bar = (struct foo) { x, y };
4405 where there is one initial value which is a constructor expression. */
4407 ;
4409 {
4412 }
4415 {
4418 }
4419 else
4420 {
4422 {
4427 }
4428 }
4429 #endif
4437 /* ANSI wants warnings about out-of-range constant initializers. */
4441 /* Check if we need to set array size from compound literal size. */
4445 {
4453 {
4457 {
4458 /* For int foo[] = (int [3]){1}; we need to set array size
4459 now since later on array initializer will be just the
4460 brace enclosed list of the compound literal. */
4464 }
4465 }
4466 }
4467 }
4468 \f
4469 /* Methods for storing and printing names for error messages. */
4471 /* Implement a spelling stack that allows components of a name to be pushed
4472 and popped. Each element on the stack is this structure. */
4474 struct spelling
4475 {
4477 union
4478 {
4482 };
4484 #define SPELLING_STRING 1
4485 #define SPELLING_MEMBER 2
4486 #define SPELLING_BOUNDS 3
4492 /* Macros to save and restore the spelling stack around push_... functions.
4493 Alternative to SAVE_SPELLING_STACK. */
4495 #define SPELLING_DEPTH() (spelling - spelling_base)
4496 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4498 /* Save and restore the spelling stack around arbitrary C code. */
4500 #define SAVE_SPELLING_DEPTH(code) \
4501 { \
4502 int __depth = SPELLING_DEPTH (); \
4503 code; \
4504 RESTORE_SPELLING_DEPTH (__depth); \
4505 }
4507 /* Push an element on the spelling stack with type KIND and assign VALUE
4508 to MEMBER. */
4510 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4511 { \
4512 int depth = SPELLING_DEPTH (); \
4513 \
4514 if (depth >= spelling_size) \
4515 { \
4516 spelling_size += 10; \
4517 if (spelling_base == 0) \
4518 spelling_base \
4519 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4520 else \
4521 spelling_base \
4522 = (struct spelling *) xrealloc (spelling_base, \
4523 spelling_size * sizeof (struct spelling)); \
4524 RESTORE_SPELLING_DEPTH (depth); \
4525 } \
4526 \
4527 spelling->kind = (KIND); \
4528 spelling->MEMBER = (VALUE); \
4529 spelling++; \
4530 }
4532 /* Push STRING on the stack. Printed literally. */
4534 static void
4537 {
4539 }
4541 /* Push a member name on the stack. Printed as '.' STRING. */
4543 static void
4545 tree decl;
4547 {
4551 }
4553 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4555 static void
4558 {
4560 }
4562 /* Compute the maximum size in bytes of the printed spelling. */
4564 static int
4566 {
4571 {
4574 else
4576 }
4579 }
4581 /* Print the spelling to BUFFER and return it. */
4586 {
4592 {
4595 }
4596 else
4597 {
4602 ;
4603 }
4606 }
4608 /* Issue an error message for a bad initializer component.
4609 MSGID identifies the message.
4610 The component name is taken from the spelling stack. */
4612 void
4615 {
4622 }
4624 /* Issue a pedantic warning for a bad initializer component.
4625 MSGID identifies the message.
4626 The component name is taken from the spelling stack. */
4628 void
4631 {
4638 }
4640 /* Issue a warning for a bad initializer component.
4641 MSGID identifies the message.
4642 The component name is taken from the spelling stack. */
4644 static void
4647 {
4654 }
4655 \f
4656 /* Digest the parser output INIT as an initializer for type TYPE.
4657 Return a C expression of type TYPE to represent the initial value.
4659 The arguments REQUIRE_CONSTANT and CONSTRUCTOR_CONSTANT request errors
4660 if non-constant initializers or elements are seen. CONSTRUCTOR_CONSTANT
4661 applies only to elements of constructors. */
4663 static tree
4667 {
4676 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4677 /* Do not use STRIP_NOPS here. We do not want an enumerator
4678 whose value is 0 to count as a null pointer constant. */
4684 /* Initialization of an array of chars from a string constant
4685 optionally enclosed in braces. */
4688 {
4696 {
4704 {
4707 }
4711 {
4714 }
4720 /* Subtract 1 (or sizeof (wchar_t))
4721 because it's ok to ignore the terminating null char
4722 that is counted in the length of the constant. */
4733 }
4734 }
4736 /* Any type can be initialized
4737 from an expression of the same type, optionally with braces. */
4751 {
4757 {
4758 /* As an extension, allow initializing objects with static storage
4759 duration with compound literals (which are then treated just as
4760 the brace enclosed list they contain). */
4763 }
4767 {
4770 }
4775 /* Compound expressions can only occur here if -pedantic or
4776 -pedantic-errors is specified. In the later case, we always want
4777 an error. In the former case, we simply want a warning. */
4780 {
4781 inside_init
4786 else
4790 }
4793 /* This test catches things like `7 / 0' which
4794 result in an expression for which TREE_CONSTANT
4795 is true, but which is not actually something
4796 that is a legal constant. We really should not
4797 be using this function, because it is a part of
4798 the back-end. Instead, the expression should
4799 already have been turned into ERROR_MARK_NODE. */
4802 {
4805 }
4808 }
4810 /* Handle scalar types, including conversions. */
4814 {
4815 /* Note that convert_for_assignment calls default_conversion
4816 for arrays and functions. We must not call it in the
4817 case where inside_init is a null pointer constant. */
4818 inside_init
4823 {
4826 }
4829 {
4832 }
4835 }
4837 /* Come here only for records and arrays. */
4840 {
4843 }
4845 /* Traditionally, you can write struct foo x = 0;
4846 and it initializes the first element of x to 0. */
4848 {
4854 {
4858 else
4865 else
4866 {
4869 }
4870 }
4873 {
4877 constructor_constant));
4879 }
4880 else
4882 }
4885 }
4886 \f
4887 /* Handle initializers that use braces. */
4889 /* Type of object we are accumulating a constructor for.
4890 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4893 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4894 left to fill. */
4897 /* For an ARRAY_TYPE, this is the specified index
4898 at which to store the next element we get. */
4901 /* For an ARRAY_TYPE, this is the maximum index. */
4904 /* For a RECORD_TYPE, this is the first field not yet written out. */
4907 /* For an ARRAY_TYPE, this is the index of the first element
4908 not yet written out. */
4911 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4912 This is so we can generate gaps between fields, when appropriate. */
4915 /* If we are saving up the elements rather than allocating them,
4916 this is the list of elements so far (in reverse order,
4917 most recent first). */
4920 /* 1 if constructor should be incrementally stored into a constructor chain,
4921 0 if all the elements should be kept in AVL tree. */
4924 /* 1 if so far this constructor's elements are all compile-time constants. */
4927 /* 1 if so far this constructor's elements are all valid address constants. */
4930 /* 1 if this constructor is erroneous so far. */
4933 /* 1 if have called defer_addressed_constants. */
4936 /* Structure for managing pending initializer elements, organized as an
4937 AVL tree. */
4939 struct init_node
4940 {
4944 tree purpose;
4945 tree value;
4946 };
4948 /* Tree of pending elements at this constructor level.
4949 These are elements encountered out of order
4950 which belong at places we haven't reached yet in actually
4951 writing the output.
4952 Will never hold tree nodes across GC runs. */
4955 /* The SPELLING_DEPTH of this constructor. */
4958 /* 0 if implicitly pushing constructor levels is allowed. */
4964 /* DECL node for which an initializer is being read.
4965 0 means we are reading a constructor expression
4966 such as (struct foo) {...}. */
4969 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4972 /* Nonzero if this is an initializer for a top-level decl. */
4975 /* Nonzero if there were any member designators in this initializer. */
4978 /* Nesting depth of designator list. */
4981 /* Nonzero if there were diagnosed errors in this designator list. */
4984 \f
4985 /* This stack has a level for each implicit or explicit level of
4986 structuring in the initializer, including the outermost one. It
4987 saves the values of most of the variables above. */
4991 struct constructor_stack
4992 {
4994 tree type;
4995 tree fields;
4996 tree index;
4997 tree max_index;
4998 tree unfilled_index;
4999 tree unfilled_fields;
5000 tree bit_index;
5001 tree elements;
5005 /* If nonzero, this value should replace the entire
5006 constructor at this level. */
5007 tree replacement_value;
5016 };
5020 /* This stack represents designators from some range designator up to
5021 the last designator in the list. */
5023 struct constructor_range_stack
5024 {
5027 tree range_start;
5028 tree index;
5029 tree range_end;
5030 tree fields;
5031 };
5035 /* This stack records separate initializers that are nested.
5036 Nested initializers can't happen in ANSI C, but GNU C allows them
5037 in cases like { ... (struct foo) { ... } ... }. */
5039 struct initializer_stack
5040 {
5042 tree decl;
5046 tree elements;
5054 };
5057 \f
5058 /* Prepare to parse and output the initializer for variable DECL. */
5060 void
5062 tree decl;
5063 tree asmspec_tree;
5065 {
5096 {
5098 require_constant_elements
5100 /* For a scalar, you can always use any value to initialize,
5101 even within braces. */
5107 }
5108 else
5109 {
5113 }
5126 }
5128 void
5130 {
5133 /* Output subconstants (string constants, usually)
5134 that were referenced within this initializer and saved up.
5135 Must do this if and only if we called defer_addressed_constants. */
5139 /* Free the whole constructor stack of this initializer. */
5141 {
5145 }
5150 /* Pop back to the data of the outer initializer (if any). */
5165 }
5166 \f
5167 /* Call here when we see the initializer is surrounded by braces.
5168 This is instead of a call to push_init_level;
5169 it is matched by a call to pop_init_level.
5171 TYPE is the type to initialize, for a constructor expression.
5172 For an initializer for a decl, TYPE is zero. */
5174 void
5176 tree type;
5177 {
5219 {
5221 /* Skip any nameless bit fields at the beginning. */
5228 }
5230 {
5232 {
5233 constructor_max_index
5236 /* Detect non-empty initializations of zero-length arrays. */
5241 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5242 to initialize VLAs will cause an proper error; avoid tree
5243 checking errors as well by setting a safe value. */
5248 constructor_index
5251 }
5252 else
5256 }
5258 {
5259 /* Vectors are like simple fixed-size arrays. */
5260 constructor_max_index =
5264 }
5265 else
5266 {
5267 /* Handle the case of int x = {5}; */
5270 }
5271 }
5272 \f
5273 /* Push down into a subobject, for initialization.
5274 If this is for an explicit set of braces, IMPLICIT is 0.
5275 If it is because the next element belongs at a lower level,
5276 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5278 void
5281 {
5285 /* If we've exhausted any levels that didn't have braces,
5286 pop them now. */
5288 {
5296 else
5298 }
5300 /* Unless this is an explicit brace, we need to preserve previous
5301 content if any. */
5303 {
5310 }
5343 {
5348 }
5350 /* Don't die if an entire brace-pair level is superfluous
5351 in the containing level. */
5353 ;
5356 {
5357 /* Don't die if there are extra init elts at the end. */
5360 else
5361 {
5364 constructor_depth++;
5365 }
5366 }
5368 {
5371 constructor_depth++;
5372 }
5375 {
5380 }
5383 {
5391 }
5394 {
5397 }
5401 {
5403 /* Skip any nameless bit fields at the beginning. */
5410 }
5412 {
5413 /* Vectors are like simple fixed-size arrays. */
5414 constructor_max_index =
5418 }
5420 {
5422 {
5423 constructor_max_index
5426 /* Detect non-empty initializations of zero-length arrays. */
5431 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5432 to initialize VLAs will cause an proper error; avoid tree
5433 checking errors as well by setting a safe value. */
5438 constructor_index
5441 }
5442 else
5447 {
5448 /* We need to split the char/wchar array into individual
5449 characters, so that we don't have to special case it
5450 everywhere. */
5452 }
5453 }
5454 else
5455 {
5459 }
5460 }
5462 /* At the end of an implicit or explicit brace level,
5463 finish up that level of constructor.
5464 If we were outputting the elements as they are read, return 0
5465 from inner levels (process_init_element ignores that),
5466 but return error_mark_node from the outermost level
5467 (that's what we want to put in DECL_INITIAL).
5468 Otherwise, return a CONSTRUCTOR expression. */
5470 tree
5473 {
5478 {
5479 /* When we come to an explicit close brace,
5480 pop any inner levels that didn't have explicit braces. */
5486 }
5490 /* Error for initializing a flexible array member, or a zero-length
5491 array member in an inappropriate context. */
5496 {
5497 /* Silently discard empty initializations. The parser will
5498 already have pedwarned for empty brackets. */
5502 {
5508 /* We have already issued an error message for the existence
5509 of a flexible array member not at the end of the structure.
5510 Discard the initializer so that we do not abort later. */
5513 }
5514 else
5515 /* Zero-length arrays are no longer special, so we should no longer
5516 get here. */
5518 }
5520 /* Warn when some struct elements are implicitly initialized to zero. */
5522 && constructor_type
5525 {
5526 /* Do not warn for flexible array members or zero-length arrays. */
5532 /* Do not warn if this level of the initializer uses member
5533 designators; it is likely to be deliberate. */
5535 {
5539 }
5540 }
5542 /* Now output all pending elements. */
5546 /* Pad out the end of the structure. */
5548 /* If this closes a superfluous brace pair,
5549 just pass out the element between them. */
5552 ;
5557 {
5558 /* A nonincremental scalar initializer--just return
5559 the element, after verifying there is just one. */
5561 {
5565 }
5567 {
5570 }
5571 else
5573 }
5574 else
5575 {
5578 else
5579 {
5586 }
5587 }
5612 {
5616 }
5618 }
5620 /* Common handling for both array range and field name designators.
5621 ARRAY argument is non-zero for array ranges. Returns zero for success. */
5623 static int
5626 {
5627 tree subtype;
5630 /* Don't die if an entire brace-pair level is superfluous
5631 in the containing level. */
5635 /* If there were errors in this designator list already, bail out silently. */
5640 {
5644 /* Designator list starts at the level of closest explicit
5645 braces. */
5650 }
5653 {
5656 }
5660 {
5664 }
5666 {
5668 }
5669 else
5674 {
5677 }
5679 {
5682 }
5687 }
5689 /* If there are range designators in designator list, push a new designator
5690 to constructor_range_stack. RANGE_END is end of such stack range or
5691 NULL_TREE if there is no range designator at this level. */
5693 static void
5695 tree range_end;
5696 {
5711 }
5713 /* Within an array initializer, specify the next index to be initialized.
5714 FIRST is that index. If LAST is nonzero, then initialize a range
5715 of indices, running from FIRST through LAST. */
5717 void
5720 {
5750 else
5751 {
5755 {
5759 {
5762 }
5763 else
5764 {
5768 {
5771 }
5772 }
5773 }
5775 designator_depth++;
5779 }
5780 }
5782 /* Within a struct initializer, specify the next field to be initialized. */
5784 void
5786 tree fieldname;
5787 {
5788 tree tail;
5797 {
5800 }
5804 {
5807 }
5812 else
5813 {
5815 designator_depth++;
5819 }
5820 }
5821 \f
5822 /* Add a new initializer to the tree of pending initializers. PURPOSE
5823 identifies the initializer, either array index or field in a structure.
5824 VALUE is the value of that index or field. */
5826 static void
5829 {
5836 {
5838 {
5844 else
5845 {
5850 }
5851 }
5852 }
5853 else
5854 {
5855 tree bitpos;
5859 {
5865 else
5866 {
5871 }
5872 }
5873 }
5886 {
5890 {
5894 {
5896 {
5897 /* L rotation. */
5910 {
5913 else
5915 }
5916 else
5918 }
5919 else
5920 {
5921 /* LR rotation. */
5943 {
5946 else
5948 }
5949 else
5951 }
5953 }
5954 else
5955 {
5956 /* p->balance == +1; growth of left side balances the node. */
5959 }
5960 }
5962 {
5964 /* Growth propagation from right side. */
5967 {
5969 {
5970 /* R rotation. */
5983 {
5986 else
5988 }
5989 else
5991 }
5993 {
5994 /* RL rotation */
6016 {
6019 else
6021 }
6022 else
6024 }
6026 }
6027 else
6028 {
6029 /* p->balance == -1; growth of right side balances the node. */
6032 }
6033 }
6037 }
6038 }
6040 /* Build AVL tree from a sorted chain. */
6042 static void
6044 {
6045 tree chain;
6055 {
6057 /* Skip any nameless bit fields at the beginning. */
6063 }
6065 {
6067 constructor_unfilled_index
6070 else
6072 }
6074 }
6076 /* Build AVL tree from a string constant. */
6078 static void
6080 tree str;
6081 {
6096 else
6107 {
6109 {
6112 }
6113 else
6114 {
6118 {
6121 else
6126 }
6127 }
6130 {
6133 {
6135 {
6138 }
6139 }
6141 {
6144 }
6149 }
6154 }
6157 }
6159 /* Return value of FIELD in pending initializer or zero if the field was
6160 not initialized yet. */
6162 static tree
6164 tree field;
6165 {
6169 {
6176 {
6181 else
6183 }
6184 }
6186 {
6190 && (!constructor_unfilled_fields
6197 {
6202 else
6204 }
6205 }
6207 {
6211 }
6213 }
6215 /* "Output" the next constructor element.
6216 At top level, really output it to assembler code now.
6217 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6218 TYPE is the data type that the containing data type wants here.
6219 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6221 PENDING if non-nil means output pending elements that belong
6222 right after this element. (PENDING is normally 1;
6223 it is 0 while outputting pending elements, to avoid recursion.) */
6225 static void
6229 {
6241 {
6242 /* As an extension, allow initializing objects with static storage
6243 duration with compound literals (which are then treated just as
6244 the brace enclosed list they contain). */
6247 }
6261 {
6264 }
6269 /* If this field is empty (and not at the end of structure),
6270 don't do anything other than checking the initializer. */
6280 require_constant_elements);
6282 {
6285 }
6287 /* If this element doesn't come next in sequence,
6288 put it on constructor_pending_elts. */
6290 && (!constructor_incremental
6292 {
6299 }
6301 && (!constructor_incremental
6303 {
6304 /* We do this for records but not for unions. In a union,
6305 no matter which field is specified, it can be initialized
6306 right away since it starts at the beginning of the union. */
6308 {
6311 else
6312 {
6320 }
6321 }
6325 }
6328 {
6332 /* We can have just one union field set. */
6334 }
6336 /* Otherwise, output this element either to
6337 constructor_elements or to the assembler file. */
6341 constructor_elements
6344 /* Advance the variable that indicates sequential elements output. */
6346 constructor_unfilled_index
6348 bitsize_one_node);
6350 {
6351 constructor_unfilled_fields
6354 /* Skip any nameless bit fields. */
6358 constructor_unfilled_fields =
6360 }
6364 /* Now output any pending elements which have become next. */
6367 }
6369 /* Output any pending elements which have become next.
6370 As we output elements, constructor_unfilled_{fields,index}
6371 advances, which may cause other elements to become next;
6372 if so, they too are output.
6374 If ALL is 0, we return when there are
6375 no more pending elements to output now.
6377 If ALL is 1, we output space as necessary so that
6378 we can output all the pending elements. */
6380 static void
6383 {
6385 tree next;
6387 retry:
6389 /* Look thru the whole pending tree.
6390 If we find an element that should be output now,
6391 output it. Otherwise, set NEXT to the element
6392 that comes first among those still pending. */
6396 {
6398 {
6400 constructor_unfilled_index))
6406 {
6407 /* Advance to the next smaller node. */
6410 else
6411 {
6412 /* We have reached the smallest node bigger than the
6413 current unfilled index. Fill the space first. */
6416 }
6417 }
6418 else
6419 {
6420 /* Advance to the next bigger node. */
6423 else
6424 {
6425 /* We have reached the biggest node in a subtree. Find
6426 the parent of it, which is the next bigger node. */
6432 {
6435 }
6436 }
6437 }
6438 }
6441 {
6444 /* If the current record is complete we are done. */
6450 /* We can't compare fields here because there might be empty
6451 fields in between. */
6453 {
6457 }
6459 {
6460 /* Advance to the next smaller node. */
6463 else
6464 {
6465 /* We have reached the smallest node bigger than the
6466 current unfilled field. Fill the space first. */
6469 }
6470 }
6471 else
6472 {
6473 /* Advance to the next bigger node. */
6476 else
6477 {
6478 /* We have reached the biggest node in a subtree. Find
6479 the parent of it, which is the next bigger node. */
6486 {
6489 }
6490 }
6491 }
6492 }
6493 }
6495 /* Ordinarily return, but not if we want to output all
6496 and there are elements left. */
6500 /* If it's not incremental, just skip over the gap, so that after
6501 jumping to retry we will output the next successive element. */
6508 /* ELT now points to the node in the pending tree with the next
6509 initializer to output. */
6511 }
6512 \f
6513 /* Add one non-braced element to the current constructor level.
6514 This adjusts the current position within the constructor's type.
6515 This may also start or terminate implicit levels
6516 to handle a partly-braced initializer.
6518 Once this has found the correct level for the new element,
6519 it calls output_init_element. */
6521 void
6523 tree value;
6524 {
6531 /* Handle superfluous braces around string cst as in
6532 char x[] = {"foo"}; */
6534 && constructor_type
6538 {
6543 }
6546 {
6549 }
6551 /* Ignore elements of a brace group if it is entirely superfluous
6552 and has already been diagnosed. */
6556 /* If we've exhausted any levels that didn't have braces,
6557 pop them now. */
6559 {
6567 constructor_index)))
6569 else
6571 }
6573 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6575 {
6576 /* If value is a compound literal and we'll be just using its
6577 content, don't put it into a SAVE_EXPR. */
6579 || !require_constant_value
6582 }
6585 {
6587 {
6588 tree fieldtype;
6592 {
6595 }
6602 /* Error for non-static initialization of a flexible array member. */
6604 && !require_constant_value
6607 {
6610 }
6612 /* Accept a string constant to initialize a subarray. */
6618 /* Otherwise, if we have come to a subaggregate,
6619 and we don't have an element of its type, push into it. */
6625 {
6628 }
6631 {
6635 }
6636 else
6637 /* Do the bookkeeping for an element that was
6638 directly output as a constructor. */
6639 {
6640 /* For a record, keep track of end position of last field. */
6642 constructor_bit_index
6648 /* Skip any nameless bit fields. */
6652 constructor_unfilled_fields =
6654 }
6657 /* Skip any nameless bit fields at the beginning. */
6662 }
6664 {
6665 tree fieldtype;
6669 {
6672 }
6679 /* Warn that traditional C rejects initialization of unions.
6680 We skip the warning if the value is zero. This is done
6681 under the assumption that the zero initializer in user
6682 code appears conditioned on e.g. __STDC__ to avoid
6683 "missing initializer" warnings and relies on default
6684 initialization to zero in the traditional C case.
6685 We also skip the warning if the initializer is designated,
6686 again on the assumption that this must be conditional on
6687 __STDC__ anyway (and we've already complained about the
6688 member-designator already). */
6693 /* Accept a string constant to initialize a subarray. */
6699 /* Otherwise, if we have come to a subaggregate,
6700 and we don't have an element of its type, push into it. */
6706 {
6709 }
6712 {
6716 }
6717 else
6718 /* Do the bookkeeping for an element that was
6719 directly output as a constructor. */
6720 {
6723 }
6726 }
6728 {
6732 /* Accept a string constant to initialize a subarray. */
6738 /* Otherwise, if we have come to a subaggregate,
6739 and we don't have an element of its type, push into it. */
6745 {
6748 }
6753 {
6756 }
6758 /* Now output the actual element. */
6760 {
6764 }
6766 constructor_index
6770 /* If we are doing the bookkeeping for an element that was
6771 directly output as a constructor, we must update
6772 constructor_unfilled_index. */
6774 }
6776 {
6779 /* Do a basic check of initializer size. Note that vectors
6780 always have a fixed size derived from their type. */
6782 {
6785 }
6787 /* Now output the actual element. */
6791 constructor_index
6795 /* If we are doing the bookkeeping for an element that was
6796 directly output as a constructor, we must update
6797 constructor_unfilled_index. */
6799 }
6801 /* Handle the sole element allowed in a braced initializer
6802 for a scalar variable. */
6804 {
6807 }
6808 else
6809 {
6813 }
6815 /* Handle range initializers either at this level or anywhere higher
6816 in the designator stack. */
6818 {
6825 {
6829 }
6833 {
6837 }
6844 {
6848 {
6851 }
6859 }
6864 }
6867 }
6870 }
6871 \f
6872 /* Build a simple asm-statement, from one string literal. */
6873 tree
6875 tree expr;
6876 {
6883 {
6884 tree stmt;
6890 NULL_TREE));
6893 }
6897 }
6899 /* Build an asm-statement, whose components are a CV_QUALIFIER, a
6900 STRING, some OUTPUTS, some INPUTS, and some CLOBBERS. */
6902 tree
6904 tree cv_qualifier;
6905 tree string;
6906 tree outputs;
6907 tree inputs;
6908 tree clobbers;
6909 {
6910 tree tail;
6915 {
6918 }
6922 {
6926 }
6928 /* We can remove output conversions that change the type,
6929 but not the mode. */
6931 {
6937 /* Allow conversions as LHS here. build_modify_expr as called below
6938 will do the right thing with them. */
6949 }
6951 /* Remove output conversions that change the type but not the mode. */
6953 {
6957 }
6959 /* Perform default conversions on array and function inputs.
6960 Don't do this for other types as it would screw up operands
6961 expected to be in memory. */
6967 }
6969 /* Expand an ASM statement with operands, handling output operands
6970 that are not variables or INDIRECT_REFS by transforming such
6971 cases into cases that expand_asm_operands can handle.
6973 Arguments are same as for expand_asm_operands. */
6975 void
6981 {
6984 /* o[I] is the place that output number I should be written. */
6986 tree tail;
6988 /* Record the contents of OUTPUTS before it is modified. */
6992 /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of
6993 OUTPUTS some trees for where the values were actually stored. */
6996 /* Copy all the intermediate outputs into the specified outputs. */
6998 {
7000 {
7005 /* Restore the original value so that it's correct the next
7006 time we expand this function. */
7008 }
7009 /* Detect modification of read-only values.
7010 (Otherwise done by build_modify_expr.) */
7011 else
7012 {
7020 }
7021 }
7023 /* Those MODIFY_EXPRs could do autoincrements. */
7025 }
7026 \f
7027 /* Expand a C `return' statement.
7028 RETVAL is the expression for what to return,
7029 or a null pointer for `return;' with no value. */
7031 tree
7033 tree retval;
7034 {
7041 {
7046 }
7048 {
7052 }
7053 else
7054 {
7058 tree inner;
7066 /* Strip any conversions, additions, and subtractions, and see if
7067 we are returning the address of a local variable. Warn if so. */
7069 {
7071 {
7078 /* If the second operand of the MINUS_EXPR has a pointer
7079 type (or is converted from it), this may be valid, so
7080 don't give a warning. */
7081 {
7095 }
7112 }
7115 }
7118 }
7121 }
7122 \f
7124 /* The SWITCH_STMT being built. */
7125 tree switch_stmt;
7126 /* A splay-tree mapping the low element of a case range to the high
7127 element, or NULL_TREE if there is no high element. Used to
7128 determine whether or not a new case label duplicates an old case
7129 label. We need a tree, rather than simply a hash table, because
7130 of the GNU case range extension. */
7131 splay_tree cases;
7132 /* The next node on the stack. */
7134 };
7136 /* A stack of the currently active switch statements. The innermost
7137 switch statement is on the top of the stack. There is no need to
7138 mark the stack for garbage collection because it is only active
7139 during the processing of the body of a function, and we never
7140 collect at that point. */
7144 /* Start a C switch statement, testing expression EXP. Return the new
7145 SWITCH_STMT. */
7147 tree
7149 tree exp;
7150 {
7156 {
7162 {
7165 }
7166 else
7167 {
7177 }
7178 }
7180 /* Add this new SWITCH_STMT to the stack. */
7188 }
7190 /* Process a case label. */
7192 tree
7194 tree low_value;
7195 tree high_value;
7196 {
7200 {
7206 }
7209 else
7213 }
7215 /* Finish the switch statement. */
7217 void
7219 {
7224 /* Pop the stack. */
7228 }