| blob | cf3a387e99fb336c5d15a1f37298820aaa5d1ce1 |
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. */
86 \f
87 /* Do `exp = require_complete_type (exp);' to make sure exp
88 does not have an incomplete type. (That includes void types.) */
90 tree
92 tree value;
93 {
99 /* First, detect a valid value with a complete type. */
105 }
107 /* Print an error message for invalid use of an incomplete type.
108 VALUE is the expression that was used (or 0 if that isn't known)
109 and TYPE is the type that was invalid. */
111 void
113 tree value;
114 tree type;
115 {
118 /* Avoid duplicate error message. */
126 else
127 {
128 retry:
129 /* We must print an error message. Be clever about what it says. */
132 {
151 {
154 }
160 }
165 else
166 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
169 }
170 }
172 /* Return a variant of TYPE which has all the type qualifiers of LIKE
173 as well as those of TYPE. */
175 static tree
178 {
181 }
182 \f
183 /* Return the common type of two types.
184 We assume that comptypes has already been done and returned 1;
185 if that isn't so, this may crash. In particular, we assume that qualifiers
186 match.
188 This is the type for the result of most arithmetic operations
189 if the operands have the given two types. */
191 tree
194 {
197 tree attributes;
199 /* Save time if the two types are the same. */
203 /* If one type is nonsense, use the other. */
209 /* Merge the attributes. */
212 /* Treat an enum type as the unsigned integer type of the same width. */
222 /* If one type is complex, form the common type of the non-complex
223 components, then make that complex. Use T1 or T2 if it is the
224 required type. */
226 {
235 else
237 attributes);
238 }
241 {
244 /* If only one is real, use it as the result. */
252 /* Both real or both integers; use the one with greater precision. */
259 /* Same precision. Prefer longs to ints even when same size. */
264 attributes);
268 {
269 /* But preserve unsignedness from the other type,
270 since long cannot hold all the values of an unsigned int. */
273 else
276 }
278 /* Likewise, prefer long double to double even if same size. */
282 attributes);
284 /* Otherwise prefer the unsigned one. */
288 else
292 /* For two pointers, do this recursively on the target type,
293 and combine the qualifiers of the two types' targets. */
294 /* This code was turned off; I don't know why.
295 But ANSI C specifies doing this with the qualifiers.
296 So I turned it on again. */
297 {
307 }
308 #if 0
311 #endif
314 {
316 /* Save space: see if the result is identical to one of the args. */
321 /* Merge the element types, and have a size if either arg has one. */
324 }
327 /* Function types: prefer the one that specified arg types.
328 If both do, merge the arg types. Also merge the return types. */
329 {
337 /* Save space: see if the result is identical to one of the args. */
343 /* Simple way if one arg fails to specify argument types. */
345 {
348 }
350 {
353 }
355 /* If both args specify argument types, we must merge the two
356 lists, argument by argument. */
371 {
372 /* A null type means arg type is not specified.
373 Take whatever the other function type has. */
375 {
378 }
380 {
383 }
385 /* Given wait (union {union wait *u; int *i} *)
386 and wait (union wait *),
387 prefer union wait * as type of parm. */
390 {
391 tree memb;
395 {
400 }
401 }
404 {
405 tree memb;
409 {
414 }
415 }
417 parm_done: ;
418 }
423 /* ... falls through ... */
424 }
428 }
430 }
431 \f
432 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
433 or various other operations. Return 2 if they are compatible
434 but a warning may be needed if you use them together. */
436 int
439 {
444 /* Suppress errors caused by previously reported errors. */
450 /* If either type is the internal version of sizetype, return the
451 language version. */
460 /* Treat an enum type as the integer type of the same width and
461 signedness. */
471 /* Different classes of types can't be compatible. */
475 /* Qualifiers must match. */
480 /* Allow for two different type nodes which have essentially the same
481 definition. Note that we already checked for equality of the type
482 qualifiers (just above). */
487 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
491 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
495 {
506 {
513 /* Target types must match incl. qualifiers. */
518 /* Sizes must match unless one is missing or variable. */
525 d1_variable = (! d1_zero
528 d2_variable = (! d2_zero
542 }
551 }
553 }
555 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
556 ignoring their qualifiers. */
558 static int
561 {
564 /* Give maybe_objc_comptypes a crack at letting these types through. */
574 }
575 \f
576 /* Subroutines of `comptypes'. */
578 /* Return 1 if two function types F1 and F2 are compatible.
579 If either type specifies no argument types,
580 the other must specify a fixed number of self-promoting arg types.
581 Otherwise, if one type specifies only the number of arguments,
582 the other must specify that number of self-promoting arg types.
583 Otherwise, the argument types must match. */
585 static int
588 {
590 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
601 /* An unspecified parmlist matches any specified parmlist
602 whose argument types don't need default promotions. */
605 {
608 /* If one of these types comes from a non-prototype fn definition,
609 compare that with the other type's arglist.
610 If they don't match, ask for a warning (but no error). */
615 }
617 {
624 }
626 /* Both types have argument lists: compare them and propagate results. */
629 }
631 /* Check two lists of types for compatibility,
632 returning 0 for incompatible, 1 for compatible,
633 or 2 for compatible with warning. */
635 static int
638 {
639 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
644 {
647 /* If one list is shorter than the other,
648 they fail to match. */
651 /* A null pointer instead of a type
652 means there is supposed to be an argument
653 but nothing is specified about what type it has.
654 So match anything that self-promotes. */
656 {
659 }
661 {
664 }
667 {
668 /* Allow wait (union {union wait *u; int *i} *)
669 and wait (union wait *) to be compatible. */
676 {
677 tree memb;
684 }
691 {
692 tree memb;
699 }
700 else
702 }
704 /* comptypes said ok, but record if it said to warn. */
710 }
711 }
712 \f
713 /* Compute the value of the `sizeof' operator. */
715 tree
717 tree type;
718 {
720 tree size;
723 {
727 }
729 {
733 }
737 {
740 }
741 else
742 /* Convert in case a char is more than one unit. */
747 /* SIZE will have an integer type with TYPE_IS_SIZETYPE set.
748 TYPE_IS_SIZETYPE means that certain things (like overflow) will
749 never happen. However, this node should really have type
750 `size_t', which is just a typedef for an ordinary integer type. */
752 }
754 tree
756 tree type;
757 {
759 tree size;
765 else
766 /* Convert in case a char is more than one unit. */
771 /* SIZE will have an integer type with TYPE_IS_SIZETYPE set.
772 TYPE_IS_SIZETYPE means that certain things (like overflow) will
773 never happen. However, this node should really have type
774 `size_t', which is just a typedef for an ordinary integer type. */
776 }
778 /* Compute the size to increment a pointer by. */
780 tree
782 tree type;
783 {
790 {
793 }
795 /* Convert in case a char is more than one unit. */
799 }
800 \f
801 /* Return either DECL or its known constant value (if it has one). */
803 tree
805 tree decl;
806 {
808 in a place where a variable is invalid. */
814 /* This is invalid if initial value is not constant.
815 If it has either a function call, a memory reference,
816 or a variable, then re-evaluating it could give different results. */
818 /* Check for cases where this is sub-optimal, even though valid. */
822 }
824 /* Return either DECL or its known constant value (if it has one), but
825 return DECL if pedantic or DECL has mode BLKmode. This is for
826 bug-compatibility with the old behavior of decl_constant_value
827 (before GCC 3.0); every use of this function is a bug and it should
828 be removed before GCC 3.1. It is not appropriate to use pedantic
829 in a way that affects optimization, and BLKmode is probably not the
830 right test for avoiding misoptimizations either. */
832 static tree
834 tree decl;
835 {
838 else
840 }
843 /* Perform the default conversion of arrays and functions to pointers.
844 Return the result of converting EXP. For any other expression, just
845 return EXP. */
847 static tree
849 tree exp;
850 {
851 tree orig_exp;
856 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
857 an lvalue.
859 Do not use STRIP_NOPS here! It will remove conversions from pointer
860 to integer and cause infinite recursion. */
865 {
869 }
871 /* Preserve the original expression code. */
876 {
878 }
880 {
881 tree adr;
883 tree ptrtype;
889 {
892 }
895 restype
906 {
910 }
914 {
915 /* Before C99, non-lvalue arrays do not decay to pointers.
916 Normally, using such an array would be invalid; but it can
917 be used correctly inside sizeof or as a statement expression.
918 Thus, do not give an error here; an error will result later. */
920 }
925 {
926 /* ??? This is not really quite correct
927 in that the type of the operand of ADDR_EXPR
928 is not the target type of the type of the ADDR_EXPR itself.
929 Question is, can this lossage be avoided? */
936 }
937 /* This way is better for a COMPONENT_REF since it can
938 simplify the offset for a component. */
941 }
943 }
945 /* Perform default promotions for C data used in expressions.
946 Arrays and functions are converted to pointers;
947 enumeral types or short or char, to int.
948 In addition, manifest constants symbols are replaced by their values. */
950 tree
952 tree exp;
953 {
954 tree orig_exp;
961 /* Constants can be used directly unless they're not loadable. */
965 /* Replace a nonvolatile const static variable with its value unless
966 it is an array, in which case we must be sure that taking the
967 address of the array produces consistent results. */
969 {
972 }
974 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
975 an lvalue.
977 Do not use STRIP_NOPS here! It will remove conversions from pointer
978 to integer and cause infinite recursion. */
985 /* Preserve the original expression code. */
989 /* Normally convert enums to int,
990 but convert wide enums to something wider. */
992 {
995 ((flag_traditional
1001 }
1005 /* If it's thinner than an int, promote it like a
1006 c_promoting_integer_type_p, otherwise leave it alone. */
1011 exp);
1014 {
1015 /* Traditionally, unsignedness is preserved in default promotions.
1016 Also preserve unsignedness if not really getting any wider. */
1018 && (flag_traditional
1023 }
1030 {
1033 }
1035 }
1036 \f
1037 /* Look up COMPONENT in a structure or union DECL.
1039 If the component name is not found, returns NULL_TREE. Otherwise,
1040 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1041 stepping down the chain to the component, which is in the last
1042 TREE_VALUE of the list. Normally the list is of length one, but if
1043 the component is embedded within (nested) anonymous structures or
1044 unions, the list steps down the chain to the component. */
1046 static tree
1049 {
1051 tree field;
1053 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1054 to the field elements. Use a binary search on this array to quickly
1055 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1056 will always be set for structures which have many elements. */
1059 {
1067 {
1072 {
1073 /* Step through all anon unions in linear fashion. */
1075 {
1079 {
1084 }
1085 }
1087 /* Entire record is only anon unions. */
1091 /* Restart the binary search, with new lower bound. */
1093 }
1099 else
1101 }
1107 }
1108 else
1109 {
1111 {
1115 {
1120 }
1124 }
1128 }
1131 }
1133 /* Make an expression to refer to the COMPONENT field of
1134 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1136 tree
1139 {
1143 tree ref;
1145 /* If DATUM is a COMPOUND_EXPR, move our reference inside it.
1146 If pedantic ensure that the arguments are not lvalues; otherwise,
1147 if the component is an array, it would wrongly decay to a pointer in
1148 C89 mode.
1149 We cannot do this with a COND_EXPR, because in a conditional expression
1150 the default promotions are applied to both sides, and this would yield
1151 the wrong type of the result; for example, if the components have
1152 type "char". */
1154 {
1156 {
1160 }
1163 }
1165 /* See if there is a field or component with name COMPONENT. */
1168 {
1170 {
1173 }
1178 {
1183 }
1185 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1186 This might be better solved in future the way the C++ front
1187 end does it - by giving the anonymous entities each a
1188 separate name and type, and then have build_component_ref
1189 recursively call itself. We can't do that here. */
1191 {
1203 }
1206 }
1212 }
1213 \f
1214 /* Given an expression PTR for a pointer, return an expression
1215 for the value pointed to.
1216 ERRORSTRING is the name of the operator to appear in error messages. */
1218 tree
1220 tree ptr;
1222 {
1227 {
1229 && !flag_volatile
1233 else
1234 {
1239 {
1242 }
1246 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1247 so that we get the proper error message if the result is used
1248 to assign to. Also, &* is supposed to be a no-op.
1249 And ANSI C seems to specify that the type of the result
1250 should be the const type. */
1251 /* A de-reference of a pointer to const is not a const. It is valid
1252 to change it via some other pointer. */
1258 }
1259 }
1263 }
1265 /* This handles expressions of the form "a[i]", which denotes
1266 an array reference.
1268 This is logically equivalent in C to *(a+i), but we may do it differently.
1269 If A is a variable or a member, we generate a primitive ARRAY_REF.
1270 This avoids forcing the array out of registers, and can work on
1271 arrays that are not lvalues (for example, members of structures returned
1272 by functions). */
1274 tree
1277 {
1279 {
1282 }
1290 {
1293 /* Subscripting with type char is likely to lose
1294 on a machine where chars are signed.
1295 So warn on any machine, but optionally.
1296 Don't warn for unsigned char since that type is safe.
1297 Don't warn for signed char because anyone who uses that
1298 must have done so deliberately. */
1303 /* Apply default promotions *after* noticing character types. */
1306 /* Require integer *after* promotion, for sake of enums. */
1308 {
1311 }
1313 /* An array that is indexed by a non-constant
1314 cannot be stored in a register; we must be able to do
1315 address arithmetic on its address.
1316 Likewise an array of elements of variable size. */
1320 {
1323 }
1324 /* An array that is indexed by a constant value which is not within
1325 the array bounds cannot be stored in a register either; because we
1326 would get a crash in store_bit_field/extract_bit_field when trying
1327 to access a non-existent part of the register. */
1331 {
1334 }
1337 {
1345 }
1349 /* Array ref is const/volatile if the array elements are
1350 or if the array is. */
1359 /* This was added by rms on 16 Nov 91.
1360 It fixes vol struct foo *a; a->elts[1]
1361 in an inline function.
1362 Hope it doesn't break something else. */
1365 }
1367 {
1371 /* Do the same warning check as above, but only on the part that's
1372 syntactically the index and only if it is also semantically
1373 the index. */
1379 /* Put the integer in IND to simplify error checking. */
1381 {
1385 }
1392 {
1395 }
1397 {
1400 }
1404 }
1405 }
1406 \f
1407 /* Build an external reference to identifier ID. FUN indicates
1408 whether this will be used for a function call. */
1409 tree
1411 tree id;
1413 {
1414 tree ref;
1419 {
1423 {
1425 /* Ordinary implicit function declaration. */
1427 else
1428 {
1429 /* Implicit declaration of built-in function. Don't
1430 change the built-in declaration, but don't let this
1431 go by silently, either. */
1434 /* only issue this warning once */
1437 }
1438 }
1439 else
1440 {
1441 /* Reference to undeclared variable, including reference to
1442 builtin outside of function-call context. */
1446 else
1447 {
1450 {
1455 {
1459 }
1460 }
1463 }
1465 }
1466 }
1467 else
1468 {
1469 /* Properly declared variable or function reference. */
1473 {
1477 }
1478 else
1480 }
1489 {
1492 }
1495 }
1497 /* Build a function call to function FUNCTION with parameters PARAMS.
1498 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1499 TREE_VALUE of each node is a parameter-expression.
1500 FUNCTION's data type may be a function type or a pointer-to-function. */
1502 tree
1505 {
1507 tree coerced_params;
1510 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1513 /* Convert anything with function type to a pointer-to-function. */
1515 {
1519 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1520 (because calling an inline function does not mean the function
1521 needs to be separately compiled). */
1527 }
1528 else
1538 {
1541 }
1543 /* fntype now gets the type of function pointed to. */
1546 /* Convert the parameters to the types declared in the
1547 function prototype, or apply default promotions. */
1549 coerced_params
1552 /* Check for errors in format strings. */
1557 /* Recognize certain built-in functions so we can make tree-codes
1558 other than CALL_EXPR. We do this when it enables fold-const.c
1559 to do something useful. */
1564 {
1569 }
1579 }
1580 \f
1581 /* Convert the argument expressions in the list VALUES
1582 to the types in the list TYPELIST. The result is a list of converted
1583 argument expressions.
1585 If TYPELIST is exhausted, or when an element has NULL as its type,
1586 perform the default conversions.
1588 PARMLIST is the chain of parm decls for the function being called.
1589 It may be 0, if that info is not available.
1590 It is used only for generating error messages.
1592 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1594 This is also where warnings about wrong number of args are generated.
1596 Both VALUES and the returned value are chains of TREE_LIST nodes
1597 with the elements of the list in the TREE_VALUE slots of those nodes. */
1599 static tree
1602 {
1607 /* Scan the given expressions and types, producing individual
1608 converted arguments and pushing them on RESULT in reverse order. */
1611 valtail;
1613 {
1618 {
1622 else
1625 }
1627 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1628 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1629 to convert automatically to a pointer. */
1638 {
1639 /* Formal parm type is specified by a function prototype. */
1640 tree parmval;
1643 {
1646 }
1647 else
1648 {
1649 /* Optionally warn about conversions that
1650 differ from the default conversions. */
1652 {
1657 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1660 warn_for_assignment ("%s as integer rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1663 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1666 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1669 warn_for_assignment ("%s as complex rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1672 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1673 /* ??? At some point, messages should be written about
1674 conversions between complex types, but that's too messy
1675 to do now. */
1678 {
1679 /* Warn if any argument is passed as `float',
1680 since without a prototype it would be `double'. */
1682 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1683 }
1684 /* Detect integer changing in width or signedness.
1685 These warnings are only activated with
1686 -Wconversion, not with -Wtraditional. */
1689 {
1696 /* No warning if function asks for enum
1697 and the actual arg is that enum type. */
1698 ;
1700 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1702 ;
1703 /* Don't complain if the formal parameter type
1704 is an enum, because we can't tell now whether
1705 the value was an enum--even the same enum. */
1707 ;
1710 /* Change in signedness doesn't matter
1711 if a constant value is unaffected. */
1712 ;
1713 /* Likewise for a constant in a NOP_EXPR. */
1717 ;
1722 /* Change in signedness doesn't matter
1723 if an enum value is unaffected. */
1724 ;
1725 #endif
1726 /* If the value is extended from a narrower
1727 unsigned type, it doesn't matter whether we
1728 pass it as signed or unsigned; the value
1729 certainly is the same either way. */
1732 ;
1735 else
1737 }
1738 }
1748 }
1750 }
1754 /* Convert `float' to `double'. */
1756 else
1757 /* Convert `short' and `char' to full-size `int'. */
1762 }
1765 {
1769 else
1771 }
1774 }
1775 \f
1776 /* This is the entry point used by the parser
1777 for binary operators in the input.
1778 In addition to constructing the expression,
1779 we check for operands that were written with other binary operators
1780 in a way that is likely to confuse the user. */
1782 tree
1786 {
1800 /* Check for cases such as x+y<<z which users are likely
1801 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1802 is cleared to prevent these warnings. */
1804 {
1806 {
1810 }
1813 {
1817 }
1820 {
1826 /* Check cases like x|y==z */
1829 }
1832 {
1838 /* Check cases like x^y==z */
1841 }
1844 {
1848 /* Check cases like x&y==z */
1851 }
1852 }
1854 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1865 /* Record the code that was specified in the source,
1866 for the sake of warnings about confusing nesting. */
1869 else
1870 {
1872 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1873 so that convert_for_assignment wouldn't strip it.
1874 That way, we got warnings for things like p = (1 - 1).
1875 But it turns out we should not get those warnings. */
1879 }
1882 }
1884 /* Build a binary-operation expression without default conversions.
1885 CODE is the kind of expression to build.
1886 This function differs from `build' in several ways:
1887 the data type of the result is computed and recorded in it,
1888 warnings are generated if arg data types are invalid,
1889 special handling for addition and subtraction of pointers is known,
1890 and some optimization is done (operations on narrow ints
1891 are done in the narrower type when that gives the same result).
1892 Constant folding is also done before the result is returned.
1894 Note that the operands will never have enumeral types, or function
1895 or array types, because either they will have the default conversions
1896 performed or they have both just been converted to some other type in which
1897 the arithmetic is to be done. */
1899 tree
1904 {
1909 /* Expression code to give to the expression when it is built.
1910 Normally this is CODE, which is what the caller asked for,
1911 but in some special cases we change it. */
1914 /* Data type in which the computation is to be performed.
1915 In the simplest cases this is the common type of the arguments. */
1918 /* Nonzero means operands have already been type-converted
1919 in whatever way is necessary.
1920 Zero means they need to be converted to RESULT_TYPE. */
1923 /* Nonzero means create the expression with this type, rather than
1924 RESULT_TYPE. */
1927 /* Nonzero means after finally constructing the expression
1928 convert it to this type. */
1931 /* Nonzero if this is an operation like MIN or MAX which can
1932 safely be computed in short if both args are promoted shorts.
1933 Also implies COMMON.
1934 -1 indicates a bitwise operation; this makes a difference
1935 in the exact conditions for when it is safe to do the operation
1936 in a narrower mode. */
1939 /* Nonzero if this is a comparison operation;
1940 if both args are promoted shorts, compare the original shorts.
1941 Also implies COMMON. */
1944 /* Nonzero if this is a right-shift operation, which can be computed on the
1945 original short and then promoted if the operand is a promoted short. */
1948 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1952 {
1955 }
1956 else
1957 {
1960 }
1965 /* The expression codes of the data types of the arguments tell us
1966 whether the arguments are integers, floating, pointers, etc. */
1970 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1974 /* If an error was already reported for one of the arguments,
1975 avoid reporting another error. */
1981 {
1983 /* Handle the pointer + int case. */
1988 else
1993 /* Subtraction of two similar pointers.
1994 We must subtract them as integers, then divide by object size. */
1998 /* Handle pointer minus int. Just like pointer plus int. */
2001 else
2014 /* Floating point division by zero is a legitimate way to obtain
2015 infinities and NaNs. */
2023 {
2026 else
2027 /* Although it would be tempting to shorten always here, that
2028 loses on some targets, since the modulo instruction is
2029 undefined if the quotient can't be represented in the
2030 computation mode. We shorten only if unsigned or if
2031 dividing by something we know != -1. */
2036 }
2045 /* If one operand is a constant, and the other is a short type
2046 that has been converted to an int,
2047 really do the work in the short type and then convert the
2048 result to int. If we are lucky, the constant will be 0 or 1
2049 in the short type, making the entire operation go away. */
2054 {
2058 }
2063 {
2067 }
2076 {
2077 /* Although it would be tempting to shorten always here, that loses
2078 on some targets, since the modulo instruction is undefined if the
2079 quotient can't be represented in the computation mode. We shorten
2080 only if unsigned or if dividing by something we know != -1. */
2085 }
2097 {
2098 /* Result of these operations is always an int,
2099 but that does not mean the operands should be
2100 converted to ints! */
2105 }
2108 /* Shift operations: result has same type as first operand;
2109 always convert second operand to int.
2110 Also set SHORT_SHIFT if shifting rightward. */
2114 {
2116 {
2119 else
2120 {
2126 }
2127 }
2129 /* Use the type of the value to be shifted.
2130 This is what most traditional C compilers do. */
2132 /* Unless traditional, convert the shift-count to an integer,
2133 regardless of size of value being shifted. */
2135 {
2138 /* Avoid converting op1 to result_type later. */
2140 }
2141 }
2146 {
2148 {
2154 }
2156 /* Use the type of the value to be shifted.
2157 This is what most traditional C compilers do. */
2159 /* Unless traditional, convert the shift-count to an integer,
2160 regardless of size of value being shifted. */
2162 {
2165 /* Avoid converting op1 to result_type later. */
2167 }
2168 }
2174 {
2176 {
2181 }
2183 /* Use the type of the value to be shifted.
2184 This is what most traditional C compilers do. */
2186 /* Unless traditional, convert the shift-count to an integer,
2187 regardless of size of value being shifted. */
2189 {
2192 /* Avoid converting op1 to result_type later. */
2194 }
2195 }
2202 /* Result of comparison is always int,
2203 but don't convert the args to int! */
2211 {
2214 /* Anything compares with void *. void * compares with anything.
2215 Otherwise, the targets must be compatible
2216 and both must be object or both incomplete. */
2220 {
2221 /* op0 != orig_op0 detects the case of something
2222 whose value is 0 but which isn't a valid null ptr const. */
2226 }
2228 {
2232 }
2233 else
2238 }
2246 {
2250 }
2252 {
2256 }
2265 {
2267 {
2272 }
2273 else
2274 {
2277 }
2278 }
2290 {
2292 {
2300 }
2301 else
2302 {
2305 }
2306 }
2309 {
2313 }
2316 {
2320 }
2322 {
2326 }
2328 {
2332 }
2344 {
2347 }
2353 }
2356 &&
2358 {
2364 /* For certain operations (which identify themselves by shorten != 0)
2365 if both args were extended from the same smaller type,
2366 do the arithmetic in that type and then extend.
2368 shorten !=0 and !=1 indicates a bitwise operation.
2369 For them, this optimization is safe only if
2370 both args are zero-extended or both are sign-extended.
2371 Otherwise, we might change the result.
2372 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2373 but calculated in (unsigned short) it would be (unsigned short)-1. */
2376 {
2380 /* UNS is 1 if the operation to be done is an unsigned one. */
2382 tree type;
2386 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2387 but it *requires* conversion to FINAL_TYPE. */
2398 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2400 /* For bitwise operations, signedness of nominal type
2401 does not matter. Consider only how operands were extended. */
2405 /* Note that in all three cases below we refrain from optimizing
2406 an unsigned operation on sign-extended args.
2407 That would not be valid. */
2409 /* Both args variable: if both extended in same way
2410 from same width, do it in that width.
2411 Do it unsigned if args were zero-extended. */
2418 result_type
2437 }
2439 /* Shifts can be shortened if shifting right. */
2442 {
2452 /* We can shorten only if the shift count is less than the
2453 number of bits in the smaller type size. */
2455 /* We cannot drop an unsigned shift after sign-extension. */
2457 {
2458 /* Do an unsigned shift if the operand was zero-extended. */
2459 result_type
2461 /* Convert value-to-be-shifted to that type. */
2465 }
2466 }
2468 /* Comparison operations are shortened too but differently.
2469 They identify themselves by setting short_compare = 1. */
2472 {
2473 /* Don't write &op0, etc., because that would prevent op0
2474 from being kept in a register.
2475 Instead, make copies of the our local variables and
2476 pass the copies by reference, then copy them back afterward. */
2479 tree val
2491 {
2503 /* Give warnings for comparisons between signed and unsigned
2504 quantities that may fail.
2506 Do the checking based on the original operand trees, so that
2507 casts will be considered, but default promotions won't be.
2509 Do not warn if the comparison is being done in a signed type,
2510 since the signed type will only be chosen if it can represent
2511 all the values of the unsigned type. */
2514 /* Do not warn if both operands are the same signedness. */
2517 else
2518 {
2523 else
2526 /* Do not warn if the signed quantity is an
2527 unsuffixed integer literal (or some static
2528 constant expression involving such literals or a
2529 conditional expression involving such literals)
2530 and it is non-negative. */
2533 /* Do not warn if the comparison is an equality operation,
2534 the unsigned quantity is an integral constant, and it
2535 would fit in the result if the result were signed. */
2540 /* Do not warn if the unsigned quantity is an enumeration
2541 constant and its maximum value would fit in the result
2542 if the result were signed. */
2548 else
2550 }
2552 /* Warn if two unsigned values are being compared in a size
2553 larger than their original size, and one (and only one) is the
2554 result of a `~' operator. This comparison will always fail.
2556 Also warn if one operand is a constant, and the constant
2557 does not have all bits set that are set in the ~ operand
2558 when it is extended. */
2562 {
2566 else
2571 {
2572 tree primop;
2577 {
2581 }
2582 else
2583 {
2587 }
2592 {
2596 }
2597 }
2604 }
2605 }
2606 }
2607 }
2609 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2610 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2611 Then the expression will be built.
2612 It will be given type FINAL_TYPE if that is nonzero;
2613 otherwise, it will be given type RESULT_TYPE. */
2616 {
2619 }
2622 {
2627 }
2632 {
2634 tree folded;
2642 }
2643 }
2644 \f
2645 /* Return a tree for the sum or difference (RESULTCODE says which)
2646 of pointer PTROP and integer INTOP. */
2648 static tree
2652 {
2653 tree size_exp;
2655 tree result;
2656 tree folded;
2658 /* The result is a pointer of the same type that is being added. */
2663 {
2667 }
2669 {
2673 }
2674 else
2677 /* If what we are about to multiply by the size of the elements
2678 contains a constant term, apply distributive law
2679 and multiply that constant term separately.
2680 This helps produce common subexpressions. */
2686 /* If the constant comes from pointer subtraction,
2687 skip this optimization--it would cause an error. */
2689 /* If the constant is unsigned, and smaller than the pointer size,
2690 then we must skip this optimization. This is because it could cause
2691 an overflow error if the constant is negative but INTOP is not. */
2695 {
2700 /* Convert both subexpression types to the type of intop,
2701 because weird cases involving pointer arithmetic
2702 can result in a sum or difference with different type args. */
2706 }
2708 /* Convert the integer argument to a type the same size as sizetype
2709 so the multiply won't overflow spuriously. */
2716 /* Replace the integer argument with a suitable product by the object size.
2717 Do this multiplication as signed, then convert to the appropriate
2718 pointer type (actually unsigned integral). */
2724 /* Create the sum or difference. */
2732 }
2734 /* Return a tree for the difference of pointers OP0 and OP1.
2735 The resulting tree has type int. */
2737 static tree
2740 {
2749 {
2754 }
2756 /* If the conversion to ptrdiff_type does anything like widening or
2757 converting a partial to an integral mode, we get a convert_expression
2758 that is in the way to do any simplifications.
2759 (fold-const.c doesn't know that the extra bits won't be needed.
2760 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2761 different mode in place.)
2762 So first try to find a common term here 'by hand'; we want to cover
2763 at least the cases that occur in legal static initializers. */
2768 {
2771 }
2772 else
2776 {
2779 }
2780 else
2784 {
2787 }
2790 /* First do the subtraction as integers;
2791 then drop through to build the divide operator.
2792 Do not do default conversions on the minus operator
2793 in case restype is a short type. */
2797 /* This generates an error if op1 is pointer to incomplete type. */
2801 /* This generates an error if op0 is pointer to incomplete type. */
2804 /* Divide by the size, in easiest possible way. */
2812 }
2813 \f
2814 /* Construct and perhaps optimize a tree representation
2815 for a unary operation. CODE, a tree_code, specifies the operation
2816 and XARG is the operand.
2817 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2818 the default promotions (such as from short to int).
2819 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2820 allows non-lvalues; this is only used to handle conversion of non-lvalue
2821 arrays to pointers in C99. */
2823 tree
2826 tree xarg;
2828 {
2829 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2833 tree val;
2842 {
2844 /* This is used for unary plus, because a CONVERT_EXPR
2845 is enough to prevent anybody from looking inside for
2846 associativity, but won't generate any code. */
2849 {
2852 }
2860 {
2863 }
2870 {
2876 }
2878 {
2881 }
2889 {
2892 }
2898 /* Conjugating a real value is a no-op, but allow it anyway. */
2901 {
2904 }
2913 /* These will convert to a pointer. */
2915 {
2918 }
2930 else
2938 else
2945 /* Handle complex lvalues (when permitted)
2946 by reduction to simpler cases. */
2952 /* Increment or decrement the real part of the value,
2953 and don't change the imaginary part. */
2955 {
2966 }
2968 /* Report invalid types. */
2972 {
2975 else
2979 }
2981 {
2982 tree inc;
2988 /* Compute the increment. */
2991 {
2992 /* If pointer target is an undefined struct,
2993 we just cannot know how to do the arithmetic. */
2995 {
2998 else
3000 }
3004 {
3007 else
3009 }
3012 }
3013 else
3018 /* Handle incrementing a cast-expression. */
3022 {
3031 /* If the real type has the same machine representation
3032 as the type it is cast to, we can make better output
3033 by adding directly to the inside of the cast. */
3039 else
3040 {
3044 else
3045 {
3049 else
3058 }
3061 }
3066 }
3067 give_up:
3069 /* Complain about anything else that is not a true lvalue. */
3076 /* Report a read-only lvalue. */
3085 else
3092 }
3095 /* Note that this operation never does default_conversion. */
3097 /* Let &* cancel out to simplify resulting code. */
3099 {
3100 /* Don't let this be an lvalue. */
3104 }
3106 /* For &x[y], return x+y */
3108 {
3113 }
3115 /* Handle complex lvalues (when permitted)
3116 by reduction to simpler cases. */
3122 float f; *&(int)f = 3.4 stores in int format
3123 whereas (int)f = 3.4 stores in float format. */
3124 /* Address of a cast is just a cast of the address
3125 of the operand of the cast. */
3127 {
3140 }
3141 #endif
3143 /* Anything not already handled and not a true memory reference
3144 or a non-lvalue array is an error. */
3149 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3152 /* If the lvalue is const or volatile, merge that into the type
3153 to which the address will point. Note that you can't get a
3154 restricted pointer by taking the address of something, so we
3155 only have to deal with `const' and `volatile' here. */
3167 {
3168 tree addr;
3171 {
3177 {
3181 }
3186 }
3187 else
3190 /* Address of a static or external variable or
3191 file-scope function counts as a constant. */
3197 }
3201 }
3206 }
3208 #if 0
3209 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3210 convert ARG with the same conversions in the same order
3211 and return the result. */
3213 static tree
3215 tree conversions;
3216 tree arg;
3217 {
3219 {
3229 arg));
3233 }
3234 }
3237 /* Return nonzero if REF is an lvalue valid for this language.
3238 Lvalues can be assigned, unless their type has TYPE_READONLY.
3239 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3241 int
3243 tree ref;
3244 {
3248 {
3273 }
3274 }
3276 /* Return nonzero if REF is an lvalue valid for this language;
3277 otherwise, print an error message and return zero. */
3279 int
3281 tree ref;
3283 {
3290 }
3292 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3293 for certain kinds of expressions which are not really lvalues
3294 but which we can accept as lvalues. If FLAG is nonzero, then
3295 non-lvalues are OK since we may be converting a non-lvalue array to
3296 a pointer in C99.
3298 If ARG is not a kind of expression we can handle, return zero. */
3300 static tree
3303 tree arg;
3305 {
3306 /* Handle (a, b) used as an "lvalue". */
3308 {
3311 /* If this returns a function type, it isn't really being used as
3312 an lvalue, so don't issue a warning about it. */
3318 }
3320 /* Handle (a ? b : c) used as an "lvalue". */
3322 {
3332 }
3335 }
3337 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3338 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3340 static void
3343 {
3346 {
3356 }
3357 }
3358 \f
3359 /* Warn about storing in something that is `const'. */
3361 void
3363 tree arg;
3365 {
3367 {
3370 else
3373 }
3377 else
3379 }
3380 \f
3381 /* Mark EXP saying that we need to be able to take the
3382 address of it; it should not be allocated in a register.
3383 Value is 1 if successful. */
3385 int
3387 tree exp;
3388 {
3392 {
3395 {
3399 }
3401 /* ... fall through ... */
3421 {
3423 {
3427 }
3430 }
3432 {
3434 {
3438 }
3440 /* If we are making this addressable due to its having
3441 volatile components, give a different error message. Also
3442 handle the case of an unnamed parameter by not trying
3443 to give the name. */
3446 {
3449 }
3453 }
3456 /* drops in */
3462 #endif
3466 }
3467 }
3468 \f
3469 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3471 tree
3474 {
3475 tree type1;
3476 tree type2;
3485 /* Don't promote the operands separately if they promote
3486 the same way. Return the unpromoted type and let the combined
3487 value get promoted if necessary. */
3493 {
3498 }
3499 #endif
3501 /* Promote both alternatives. */
3518 /* Quickly detect the usual case where op1 and op2 have the same type
3519 after promotion. */
3521 {
3524 else
3526 }
3531 {
3534 /* If -Wsign-compare, warn here if type1 and type2 have
3535 different signedness. We'll promote the signed to unsigned
3536 and later code won't know it used to be different.
3537 Do this check on the original types, so that explicit casts
3538 will be considered, but default promotions won't. */
3541 {
3546 {
3547 /* Do not warn if the result type is signed, since the
3548 signed type will only be chosen if it can represent
3549 all the values of the unsigned type. */
3552 /* Do not warn if the signed quantity is an unsuffixed
3553 integer literal (or some static constant expression
3554 involving such literals) and it is non-negative. */
3558 else
3560 }
3561 }
3562 }
3564 {
3568 }
3570 {
3580 {
3585 }
3587 {
3592 }
3593 else
3594 {
3597 }
3598 }
3600 {
3603 else
3604 {
3606 }
3608 }
3610 {
3613 else
3614 {
3616 }
3618 }
3621 {
3624 else
3625 {
3628 }
3629 }
3631 /* Merge const and volatile flags of the incoming types. */
3632 result_type
3646 }
3647 \f
3648 /* Given a list of expressions, return a compound expression
3649 that performs them all and returns the value of the last of them. */
3651 tree
3653 tree list;
3654 {
3656 }
3658 static tree
3660 tree list;
3662 {
3663 tree rest;
3666 {
3667 /* Convert arrays and functions to pointers when there
3668 really is a comma operator. */
3674 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3676 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3679 #endif
3681 /* Don't let (0, 0) be null pointer constant. */
3685 }
3690 {
3691 /* The left-hand operand of a comma expression is like an expression
3692 statement: with -W or -Wunused, we should warn if it doesn't have
3693 any side-effects, unless it was explicitly cast to (void). */
3699 /* When pedantic, a compound expression can be neither an lvalue
3700 nor an integer constant expression. */
3703 }
3705 /* With -Wunused, we should also warn if the left-hand operand does have
3706 side-effects, but computes a value which is not used. For example, in
3707 `foo() + bar(), baz()' the result of the `+' operator is not used,
3708 so we should issue a warning. */
3713 }
3715 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3717 tree
3719 tree type;
3720 tree expr;
3721 {
3728 #if 0
3729 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3732 #endif
3735 {
3738 }
3741 {
3744 }
3747 {
3749 {
3753 }
3754 }
3756 {
3757 tree field;
3766 {
3768 tree t;
3773 {
3776 else
3778 }
3779 else
3786 }
3789 }
3790 else
3791 {
3794 /* If casting to void, avoid the error that would come
3795 from default_conversion in the case of a non-lvalue array. */
3799 /* Convert functions and arrays to pointers,
3800 but don't convert any other types. */
3804 /* Optionally warn about potentially worrisome casts. */
3809 {
3814 /* Check that the qualifiers on IN_TYPE are a superset of
3815 the qualifiers of IN_OTYPE. The outermost level of
3816 POINTER_TYPE nodes is uninteresting and we stop as soon
3817 as we hit a non-POINTER_TYPE node on either type. */
3818 do
3819 {
3823 }
3828 /* There are qualifiers present in IN_OTYPE that are not
3829 present in IN_TYPE. */
3831 }
3833 /* Warn about possible alignment problems. */
3839 /* Don't warn about opaque types, where the actual alignment
3840 restriction is unknown. */
3861 /* Don't warn about converting any constant. */
3868 /* Ignore any integer overflow caused by the cast. */
3870 {
3873 }
3874 }
3876 /* Pedantically, don't let (void *) (FOO *) 0 be a null pointer constant. */
3882 /* If pedantic, don't let a cast be an lvalue. */
3887 }
3889 /* Interpret a cast of expression EXPR to type TYPE. */
3890 tree
3893 {
3896 /* This avoids warnings about unprototyped casts on
3897 integers. E.g. "#define SIG_DFL (void(*)())0". */
3904 }
3906 \f
3907 /* Build an assignment expression of lvalue LHS from value RHS.
3908 MODIFYCODE is the code for a binary operator that we use
3909 to combine the old value of LHS with RHS to get the new value.
3910 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3912 tree
3916 {
3917 tree result;
3918 tree newrhs;
3922 /* Types that aren't fully specified cannot be used in assignments. */
3925 /* Avoid duplicate error messages from operands that had errors. */
3929 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3930 /* Do not use STRIP_NOPS here. We do not want an enumerator
3931 whose value is 0 to count as a null pointer constant. */
3937 /* Handle control structure constructs used as "lvalues". */
3940 {
3941 /* Handle (a, b) used as an "lvalue". */
3950 /* Handle (a ? b : c) used as an "lvalue". */
3954 {
3955 /* Produce (a ? (b = rhs) : (c = rhs))
3956 except that the RHS goes through a save-expr
3957 so the code to compute it is only emitted once. */
3958 tree cond
3966 /* Make sure the code to compute the rhs comes out
3967 before the split. */
3969 /* But cast it to void to avoid an "unused" error. */
3971 }
3974 }
3976 /* If a binary op has been requested, combine the old LHS value with the RHS
3977 producing the value we should actually store into the LHS. */
3980 {
3983 }
3985 /* Handle a cast used as an "lvalue".
3986 We have already performed any binary operator using the value as cast.
3987 Now convert the result to the cast type of the lhs,
3988 and then true type of the lhs and store it there;
3989 then convert result back to the cast type to be the value
3990 of the assignment. */
3993 {
4002 {
4004 tree result;
4012 }
4016 }
4018 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
4019 Reject anything strange now. */
4024 /* Warn about storing in something that is `const'. */
4032 /* If storing into a structure or union member,
4033 it has probably been given type `int'.
4034 Compute the type that would go with
4035 the actual amount of storage the member occupies. */
4044 /* If storing in a field that is in actuality a short or narrower than one,
4045 we must store in the field in its actual type. */
4048 {
4051 }
4053 /* Convert new value to destination type. */
4060 /* Scan operands */
4065 /* If we got the LHS in a different type for storing in,
4066 convert the result back to the nominal type of LHS
4067 so that the value we return always has the same type
4068 as the LHS argument. */
4074 }
4075 \f
4076 /* Convert value RHS to type TYPE as preparation for an assignment
4077 to an lvalue of type TYPE.
4078 The real work of conversion is done by `convert'.
4079 The purpose of this function is to generate error messages
4080 for assignments that are not allowed in C.
4081 ERRTYPE is a string to use in error messages:
4082 "assignment", "return", etc. If it is null, this is parameter passing
4083 for a function call (and different error messages are output).
4085 FUNNAME is the name of the function being called,
4086 as an IDENTIFIER_NODE, or null.
4087 PARMNUM is the number of the argument, for printing in error messages. */
4089 static tree
4095 {
4097 tree rhstype;
4100 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4101 /* Do not use STRIP_NOPS here. We do not want an enumerator
4102 whose value is 0 to count as a null pointer constant. */
4119 {
4121 /* Check for Objective-C protocols. This will issue a warning if
4122 there are protocol violations. No need to use the return value. */
4125 }
4128 {
4131 }
4132 /* A type converts to a reference to it.
4133 This code doesn't fully support references, it's just for the
4134 special case of va_start and va_copy. */
4137 {
4142 /* We already know that these two types are compatible, but they
4143 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4144 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4145 likely to be va_list, a typedef to __builtin_va_list, which
4146 is different enough that it will cause problems later. */
4152 }
4153 /* Arithmetic types all interconvert, and enum is treated like int. */
4162 /* Conversion to a transparent union from its member types.
4163 This applies only to function arguments. */
4165 {
4166 tree memb_types;
4171 {
4182 {
4186 /* Any non-function converts to a [const][volatile] void *
4187 and vice versa; otherwise, targets must be the same.
4188 Meanwhile, the lhs target must have all the qualifiers of
4189 the rhs. */
4192 {
4193 /* If this type won't generate any warnings, use it. */
4203 /* Keep looking for a better type, but remember this one. */
4206 }
4207 }
4209 /* Can convert integer zero to any pointer type. */
4213 {
4216 }
4217 }
4220 {
4222 {
4223 /* We have only a marginally acceptable member type;
4224 it needs a warning. */
4228 /* Const and volatile mean something different for function
4229 types, so the usual warnings are not appropriate. */
4232 {
4233 /* Because const and volatile on functions are
4234 restrictions that say the function will not do
4235 certain things, it is okay to use a const or volatile
4236 function where an ordinary one is wanted, but not
4237 vice-versa. */
4241 }
4245 parmnum);
4246 }
4252 }
4253 }
4255 /* Conversions among pointers */
4258 {
4262 /* Any non-function converts to a [const][volatile] void *
4263 and vice versa; otherwise, targets must be the same.
4264 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4269 {
4272 ||
4274 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4275 which are not ANSI null ptr constants. */
4280 /* Const and volatile mean something different for function types,
4281 so the usual warnings are not appropriate. */
4284 {
4288 /* If this is not a case of ignoring a mismatch in signedness,
4289 no warning. */
4292 ;
4293 /* If there is a mismatch, do warn. */
4297 }
4300 {
4301 /* Because const and volatile on functions are restrictions
4302 that say the function will not do certain things,
4303 it is okay to use a const or volatile function
4304 where an ordinary one is wanted, but not vice-versa. */
4308 }
4309 }
4310 else
4314 }
4316 {
4317 /* An explicit constant 0 can convert to a pointer,
4318 or one that results from arithmetic, even including
4319 a cast to integer type. */
4321 &&
4326 {
4330 }
4332 }
4334 {
4338 }
4343 {
4345 {
4351 else
4354 }
4355 else
4357 parmnum);
4358 }
4359 else
4363 }
4365 /* Print a warning using MSGID.
4366 It gets OPNAME as its one parameter.
4367 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4368 FUNCTION and ARGNUM are handled specially if we are building an
4369 Objective-C selector. */
4371 static void
4375 tree function;
4377 {
4379 {
4384 {
4387 }
4389 {
4390 /* Function name is known; supply it. */
4397 }
4398 else
4399 {
4400 /* Function name unknown (call through ptr); just give arg number.*/
4404 }
4406 }
4408 }
4409 \f
4410 /* If VALUE is a compound expr all of whose expressions are constant, then
4411 return its value. Otherwise, return error_mark_node.
4413 This is for handling COMPOUND_EXPRs as initializer elements
4414 which is allowed with a warning when -pedantic is specified. */
4416 static tree
4418 tree value;
4419 tree endtype;
4420 {
4422 {
4427 endtype);
4428 }
4432 else
4434 }
4435 \f
4436 /* Perform appropriate conversions on the initial value of a variable,
4437 store it in the declaration DECL,
4438 and print any error messages that are appropriate.
4439 If the init is invalid, store an ERROR_MARK. */
4441 void
4444 {
4447 /* If variable's type was invalidly declared, just ignore it. */
4453 /* Digest the specified initializer into an expression. */
4458 /* Store the expression if valid; else report error. */
4460 #if 0
4461 /* Note that this is the only place we can detect the error
4462 in a case such as struct foo bar = (struct foo) { x, y };
4463 where there is one initial value which is a constructor expression. */
4465 ;
4467 {
4470 }
4473 {
4476 }
4477 else
4478 {
4480 {
4485 }
4486 }
4487 #endif
4495 /* ANSI wants warnings about out-of-range constant initializers. */
4499 /* Check if we need to set array size from compound literal size. */
4503 {
4511 {
4515 {
4516 /* For int foo[] = (int [3]){1}; we need to set array size
4517 now since later on array initializer will be just the
4518 brace enclosed list of the compound literal. */
4522 }
4523 }
4524 }
4525 }
4526 \f
4527 /* Methods for storing and printing names for error messages. */
4529 /* Implement a spelling stack that allows components of a name to be pushed
4530 and popped. Each element on the stack is this structure. */
4532 struct spelling
4533 {
4535 union
4536 {
4540 };
4542 #define SPELLING_STRING 1
4543 #define SPELLING_MEMBER 2
4544 #define SPELLING_BOUNDS 3
4550 /* Macros to save and restore the spelling stack around push_... functions.
4551 Alternative to SAVE_SPELLING_STACK. */
4553 #define SPELLING_DEPTH() (spelling - spelling_base)
4554 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4556 /* Save and restore the spelling stack around arbitrary C code. */
4558 #define SAVE_SPELLING_DEPTH(code) \
4559 { \
4560 int __depth = SPELLING_DEPTH (); \
4561 code; \
4562 RESTORE_SPELLING_DEPTH (__depth); \
4563 }
4565 /* Push an element on the spelling stack with type KIND and assign VALUE
4566 to MEMBER. */
4568 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4569 { \
4570 int depth = SPELLING_DEPTH (); \
4571 \
4572 if (depth >= spelling_size) \
4573 { \
4574 spelling_size += 10; \
4575 if (spelling_base == 0) \
4576 spelling_base \
4577 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4578 else \
4579 spelling_base \
4580 = (struct spelling *) xrealloc (spelling_base, \
4581 spelling_size * sizeof (struct spelling)); \
4582 RESTORE_SPELLING_DEPTH (depth); \
4583 } \
4584 \
4585 spelling->kind = (KIND); \
4586 spelling->MEMBER = (VALUE); \
4587 spelling++; \
4588 }
4590 /* Push STRING on the stack. Printed literally. */
4592 static void
4595 {
4597 }
4599 /* Push a member name on the stack. Printed as '.' STRING. */
4601 static void
4603 tree decl;
4605 {
4609 }
4611 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4613 static void
4616 {
4618 }
4620 /* Compute the maximum size in bytes of the printed spelling. */
4622 static int
4624 {
4629 {
4632 else
4634 }
4637 }
4639 /* Print the spelling to BUFFER and return it. */
4644 {
4650 {
4653 }
4654 else
4655 {
4660 ;
4661 }
4664 }
4666 /* Issue an error message for a bad initializer component.
4667 MSGID identifies the message.
4668 The component name is taken from the spelling stack. */
4670 void
4673 {
4680 }
4682 /* Issue a pedantic warning for a bad initializer component.
4683 MSGID identifies the message.
4684 The component name is taken from the spelling stack. */
4686 void
4689 {
4696 }
4698 /* Issue a warning for a bad initializer component.
4699 MSGID identifies the message.
4700 The component name is taken from the spelling stack. */
4702 static void
4705 {
4712 }
4713 \f
4714 /* Digest the parser output INIT as an initializer for type TYPE.
4715 Return a C expression of type TYPE to represent the initial value.
4717 The arguments REQUIRE_CONSTANT and CONSTRUCTOR_CONSTANT request errors
4718 if non-constant initializers or elements are seen. CONSTRUCTOR_CONSTANT
4719 applies only to elements of constructors. */
4721 static tree
4725 {
4734 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4735 /* Do not use STRIP_NOPS here. We do not want an enumerator
4736 whose value is 0 to count as a null pointer constant. */
4742 /* Initialization of an array of chars from a string constant
4743 optionally enclosed in braces. */
4746 {
4754 {
4762 {
4765 }
4769 {
4772 }
4778 /* Subtract 1 (or sizeof (wchar_t))
4779 because it's ok to ignore the terminating null char
4780 that is counted in the length of the constant. */
4791 }
4792 }
4794 /* Any type can be initialized
4795 from an expression of the same type, optionally with braces. */
4807 {
4813 {
4814 /* As an extension, allow initializing objects with static storage
4815 duration with compound literals (which are then treated just as
4816 the brace enclosed list they contain). */
4819 }
4823 {
4826 }
4831 /* Compound expressions can only occur here if -pedantic or
4832 -pedantic-errors is specified. In the later case, we always want
4833 an error. In the former case, we simply want a warning. */
4836 {
4837 inside_init
4842 else
4846 }
4849 /* This test catches things like `7 / 0' which
4850 result in an expression for which TREE_CONSTANT
4851 is true, but which is not actually something
4852 that is a legal constant. We really should not
4853 be using this function, because it is a part of
4854 the back-end. Instead, the expression should
4855 already have been turned into ERROR_MARK_NODE. */
4858 {
4861 }
4864 }
4866 /* Handle scalar types, including conversions. */
4870 {
4871 /* Note that convert_for_assignment calls default_conversion
4872 for arrays and functions. We must not call it in the
4873 case where inside_init is a null pointer constant. */
4874 inside_init
4879 {
4882 }
4885 {
4888 }
4891 }
4893 /* Come here only for records and arrays. */
4896 {
4899 }
4901 /* Traditionally, you can write struct foo x = 0;
4902 and it initializes the first element of x to 0. */
4904 {
4910 {
4914 else
4921 else
4922 {
4925 }
4926 }
4929 {
4933 constructor_constant));
4935 }
4936 else
4938 }
4941 }
4942 \f
4943 /* Handle initializers that use braces. */
4945 /* Type of object we are accumulating a constructor for.
4946 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4949 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4950 left to fill. */
4953 /* For an ARRAY_TYPE, this is the specified index
4954 at which to store the next element we get. */
4957 /* For an ARRAY_TYPE, this is the maximum index. */
4960 /* For a RECORD_TYPE, this is the first field not yet written out. */
4963 /* For an ARRAY_TYPE, this is the index of the first element
4964 not yet written out. */
4967 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4968 This is so we can generate gaps between fields, when appropriate. */
4971 /* If we are saving up the elements rather than allocating them,
4972 this is the list of elements so far (in reverse order,
4973 most recent first). */
4976 /* 1 if constructor should be incrementally stored into a constructor chain,
4977 0 if all the elements should be kept in AVL tree. */
4980 /* 1 if so far this constructor's elements are all compile-time constants. */
4983 /* 1 if so far this constructor's elements are all valid address constants. */
4986 /* 1 if this constructor is erroneous so far. */
4989 /* 1 if have called defer_addressed_constants. */
4992 /* Structure for managing pending initializer elements, organized as an
4993 AVL tree. */
4995 struct init_node
4996 {
5000 tree purpose;
5001 tree value;
5002 };
5004 /* Tree of pending elements at this constructor level.
5005 These are elements encountered out of order
5006 which belong at places we haven't reached yet in actually
5007 writing the output.
5008 Will never hold tree nodes across GC runs. */
5011 /* The SPELLING_DEPTH of this constructor. */
5014 /* 0 if implicitly pushing constructor levels is allowed. */
5020 /* DECL node for which an initializer is being read.
5021 0 means we are reading a constructor expression
5022 such as (struct foo) {...}. */
5025 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
5028 /* Nonzero if this is an initializer for a top-level decl. */
5031 /* Nonzero if there were any member designators in this initializer. */
5034 /* Nesting depth of designator list. */
5037 /* Nonzero if there were diagnosed errors in this designator list. */
5040 \f
5041 /* This stack has a level for each implicit or explicit level of
5042 structuring in the initializer, including the outermost one. It
5043 saves the values of most of the variables above. */
5047 struct constructor_stack
5048 {
5050 tree type;
5051 tree fields;
5052 tree index;
5053 tree max_index;
5054 tree unfilled_index;
5055 tree unfilled_fields;
5056 tree bit_index;
5057 tree elements;
5061 /* If nonzero, this value should replace the entire
5062 constructor at this level. */
5063 tree replacement_value;
5072 };
5076 /* This stack represents designators from some range designator up to
5077 the last designator in the list. */
5079 struct constructor_range_stack
5080 {
5083 tree range_start;
5084 tree index;
5085 tree range_end;
5086 tree fields;
5087 };
5091 /* This stack records separate initializers that are nested.
5092 Nested initializers can't happen in ANSI C, but GNU C allows them
5093 in cases like { ... (struct foo) { ... } ... }. */
5095 struct initializer_stack
5096 {
5098 tree decl;
5102 tree elements;
5110 };
5113 \f
5114 /* Prepare to parse and output the initializer for variable DECL. */
5116 void
5118 tree decl;
5119 tree asmspec_tree;
5121 {
5152 {
5154 require_constant_elements
5156 /* For a scalar, you can always use any value to initialize,
5157 even within braces. */
5163 }
5164 else
5165 {
5169 }
5182 }
5184 void
5186 {
5189 /* Output subconstants (string constants, usually)
5190 that were referenced within this initializer and saved up.
5191 Must do this if and only if we called defer_addressed_constants. */
5195 /* Free the whole constructor stack of this initializer. */
5197 {
5201 }
5206 /* Pop back to the data of the outer initializer (if any). */
5221 }
5222 \f
5223 /* Call here when we see the initializer is surrounded by braces.
5224 This is instead of a call to push_init_level;
5225 it is matched by a call to pop_init_level.
5227 TYPE is the type to initialize, for a constructor expression.
5228 For an initializer for a decl, TYPE is zero. */
5230 void
5232 tree type;
5233 {
5275 {
5277 /* Skip any nameless bit fields at the beginning. */
5284 }
5286 {
5288 {
5289 constructor_max_index
5292 /* Detect non-empty initializations of zero-length arrays. */
5297 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5298 to initialize VLAs will cause an proper error; avoid tree
5299 checking errors as well by setting a safe value. */
5304 constructor_index
5307 }
5308 else
5312 }
5313 else
5314 {
5315 /* Handle the case of int x = {5}; */
5318 }
5319 }
5320 \f
5321 /* Push down into a subobject, for initialization.
5322 If this is for an explicit set of braces, IMPLICIT is 0.
5323 If it is because the next element belongs at a lower level,
5324 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5326 void
5329 {
5333 /* If we've exhausted any levels that didn't have braces,
5334 pop them now. */
5336 {
5344 else
5346 }
5348 /* Unless this is an explicit brace, we need to preserve previous
5349 content if any. */
5351 {
5358 }
5391 {
5396 }
5398 /* Don't die if an entire brace-pair level is superfluous
5399 in the containing level. */
5401 ;
5404 {
5405 /* Don't die if there are extra init elts at the end. */
5408 else
5409 {
5412 constructor_depth++;
5413 }
5414 }
5416 {
5419 constructor_depth++;
5420 }
5423 {
5428 }
5431 {
5439 }
5442 {
5445 }
5449 {
5451 /* Skip any nameless bit fields at the beginning. */
5458 }
5460 {
5462 {
5463 constructor_max_index
5466 /* Detect non-empty initializations of zero-length arrays. */
5471 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5472 to initialize VLAs will cause an proper error; avoid tree
5473 checking errors as well by setting a safe value. */
5478 constructor_index
5481 }
5482 else
5487 {
5488 /* We need to split the char/wchar array into individual
5489 characters, so that we don't have to special case it
5490 everywhere. */
5492 }
5493 }
5494 else
5495 {
5499 }
5500 }
5502 /* At the end of an implicit or explicit brace level,
5503 finish up that level of constructor.
5504 If we were outputting the elements as they are read, return 0
5505 from inner levels (process_init_element ignores that),
5506 but return error_mark_node from the outermost level
5507 (that's what we want to put in DECL_INITIAL).
5508 Otherwise, return a CONSTRUCTOR expression. */
5510 tree
5513 {
5518 {
5519 /* When we come to an explicit close brace,
5520 pop any inner levels that didn't have explicit braces. */
5526 }
5530 /* Error for initializing a flexible array member, or a zero-length
5531 array member in an inappropriate context. */
5536 {
5537 /* Silently discard empty initializations. The parser will
5538 already have pedwarned for empty brackets. */
5542 {
5548 /* We have already issued an error message for the existence
5549 of a flexible array member not at the end of the structure.
5550 Discard the initializer so that we do not abort later. */
5553 }
5554 else
5555 /* Zero-length arrays are no longer special, so we should no longer
5556 get here. */
5558 }
5560 /* Warn when some struct elements are implicitly initialized to zero. */
5562 && constructor_type
5565 {
5566 /* Do not warn for flexible array members or zero-length arrays. */
5572 /* Do not warn if this level of the initializer uses member
5573 designators; it is likely to be deliberate. */
5575 {
5579 }
5580 }
5582 /* Now output all pending elements. */
5586 /* Pad out the end of the structure. */
5588 /* If this closes a superfluous brace pair,
5589 just pass out the element between them. */
5592 ;
5596 {
5597 /* A nonincremental scalar initializer--just return
5598 the element, after verifying there is just one. */
5600 {
5604 }
5606 {
5609 }
5610 else
5612 }
5613 else
5614 {
5617 else
5618 {
5625 }
5626 }
5651 {
5655 }
5657 }
5659 /* Common handling for both array range and field name designators.
5660 ARRAY argument is non-zero for array ranges. Returns zero for success. */
5662 static int
5665 {
5666 tree subtype;
5669 /* Don't die if an entire brace-pair level is superfluous
5670 in the containing level. */
5674 /* If there were errors in this designator list already, bail out silently. */
5679 {
5683 /* Designator list starts at the level of closest explicit
5684 braces. */
5689 }
5692 {
5695 }
5699 {
5703 }
5705 {
5707 }
5708 else
5713 {
5716 }
5718 {
5721 }
5726 }
5728 /* If there are range designators in designator list, push a new designator
5729 to constructor_range_stack. RANGE_END is end of such stack range or
5730 NULL_TREE if there is no range designator at this level. */
5732 static void
5734 tree range_end;
5735 {
5750 }
5752 /* Within an array initializer, specify the next index to be initialized.
5753 FIRST is that index. If LAST is nonzero, then initialize a range
5754 of indices, running from FIRST through LAST. */
5756 void
5759 {
5789 else
5790 {
5794 {
5798 {
5801 }
5802 else
5803 {
5807 {
5810 }
5811 }
5812 }
5814 designator_depth++;
5818 }
5819 }
5821 /* Within a struct initializer, specify the next field to be initialized. */
5823 void
5825 tree fieldname;
5826 {
5827 tree tail;
5836 {
5839 }
5843 {
5846 }
5851 else
5852 {
5854 designator_depth++;
5858 }
5859 }
5860 \f
5861 /* Add a new initializer to the tree of pending initializers. PURPOSE
5862 identifies the initializer, either array index or field in a structure.
5863 VALUE is the value of that index or field. */
5865 static void
5868 {
5875 {
5877 {
5883 else
5884 {
5889 }
5890 }
5891 }
5892 else
5893 {
5894 tree bitpos;
5898 {
5904 else
5905 {
5910 }
5911 }
5912 }
5925 {
5929 {
5933 {
5935 {
5936 /* L rotation. */
5949 {
5952 else
5954 }
5955 else
5957 }
5958 else
5959 {
5960 /* LR rotation. */
5982 {
5985 else
5987 }
5988 else
5990 }
5992 }
5993 else
5994 {
5995 /* p->balance == +1; growth of left side balances the node. */
5998 }
5999 }
6001 {
6003 /* Growth propagation from right side. */
6006 {
6008 {
6009 /* R rotation. */
6022 {
6025 else
6027 }
6028 else
6030 }
6032 {
6033 /* RL rotation */
6055 {
6058 else
6060 }
6061 else
6063 }
6065 }
6066 else
6067 {
6068 /* p->balance == -1; growth of right side balances the node. */
6071 }
6072 }
6076 }
6077 }
6079 /* Build AVL tree from a sorted chain. */
6081 static void
6083 {
6084 tree chain;
6094 {
6096 /* Skip any nameless bit fields at the beginning. */
6102 }
6104 {
6106 constructor_unfilled_index
6109 else
6111 }
6113 }
6115 /* Build AVL tree from a string constant. */
6117 static void
6119 tree str;
6120 {
6135 else
6146 {
6148 {
6151 }
6152 else
6153 {
6157 {
6160 else
6165 }
6166 }
6169 {
6172 {
6174 {
6177 }
6178 }
6180 {
6183 }
6188 }
6193 }
6196 }
6198 /* Return value of FIELD in pending initializer or zero if the field was
6199 not initialized yet. */
6201 static tree
6203 tree field;
6204 {
6208 {
6215 {
6220 else
6222 }
6223 }
6225 {
6229 && (!constructor_unfilled_fields
6236 {
6241 else
6243 }
6244 }
6246 {
6250 }
6252 }
6254 /* "Output" the next constructor element.
6255 At top level, really output it to assembler code now.
6256 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6257 TYPE is the data type that the containing data type wants here.
6258 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6260 PENDING if non-nil means output pending elements that belong
6261 right after this element. (PENDING is normally 1;
6262 it is 0 while outputting pending elements, to avoid recursion.) */
6264 static void
6268 {
6280 {
6281 /* As an extension, allow initializing objects with static storage
6282 duration with compound literals (which are then treated just as
6283 the brace enclosed list they contain). */
6286 }
6300 {
6303 }
6308 /* If this field is empty (and not at the end of structure),
6309 don't do anything other than checking the initializer. */
6319 require_constant_elements);
6321 {
6324 }
6326 /* If this element doesn't come next in sequence,
6327 put it on constructor_pending_elts. */
6329 && (!constructor_incremental
6331 {
6338 }
6340 && (!constructor_incremental
6342 {
6343 /* We do this for records but not for unions. In a union,
6344 no matter which field is specified, it can be initialized
6345 right away since it starts at the beginning of the union. */
6347 {
6350 else
6351 {
6359 }
6360 }
6364 }
6367 {
6371 /* We can have just one union field set. */
6373 }
6375 /* Otherwise, output this element either to
6376 constructor_elements or to the assembler file. */
6380 constructor_elements
6383 /* Advance the variable that indicates sequential elements output. */
6385 constructor_unfilled_index
6387 bitsize_one_node);
6389 {
6390 constructor_unfilled_fields
6393 /* Skip any nameless bit fields. */
6397 constructor_unfilled_fields =
6399 }
6403 /* Now output any pending elements which have become next. */
6406 }
6408 /* Output any pending elements which have become next.
6409 As we output elements, constructor_unfilled_{fields,index}
6410 advances, which may cause other elements to become next;
6411 if so, they too are output.
6413 If ALL is 0, we return when there are
6414 no more pending elements to output now.
6416 If ALL is 1, we output space as necessary so that
6417 we can output all the pending elements. */
6419 static void
6422 {
6424 tree next;
6426 retry:
6428 /* Look thru the whole pending tree.
6429 If we find an element that should be output now,
6430 output it. Otherwise, set NEXT to the element
6431 that comes first among those still pending. */
6435 {
6437 {
6439 constructor_unfilled_index))
6445 {
6446 /* Advance to the next smaller node. */
6449 else
6450 {
6451 /* We have reached the smallest node bigger than the
6452 current unfilled index. Fill the space first. */
6455 }
6456 }
6457 else
6458 {
6459 /* Advance to the next bigger node. */
6462 else
6463 {
6464 /* We have reached the biggest node in a subtree. Find
6465 the parent of it, which is the next bigger node. */
6471 {
6474 }
6475 }
6476 }
6477 }
6480 {
6483 /* If the current record is complete we are done. */
6489 /* We can't compare fields here because there might be empty
6490 fields in between. */
6492 {
6496 }
6498 {
6499 /* Advance to the next smaller node. */
6502 else
6503 {
6504 /* We have reached the smallest node bigger than the
6505 current unfilled field. Fill the space first. */
6508 }
6509 }
6510 else
6511 {
6512 /* Advance to the next bigger node. */
6515 else
6516 {
6517 /* We have reached the biggest node in a subtree. Find
6518 the parent of it, which is the next bigger node. */
6525 {
6528 }
6529 }
6530 }
6531 }
6532 }
6534 /* Ordinarily return, but not if we want to output all
6535 and there are elements left. */
6539 /* If it's not incremental, just skip over the gap, so that after
6540 jumping to retry we will output the next successive element. */
6547 /* ELT now points to the node in the pending tree with the next
6548 initializer to output. */
6550 }
6551 \f
6552 /* Add one non-braced element to the current constructor level.
6553 This adjusts the current position within the constructor's type.
6554 This may also start or terminate implicit levels
6555 to handle a partly-braced initializer.
6557 Once this has found the correct level for the new element,
6558 it calls output_init_element. */
6560 void
6562 tree value;
6563 {
6570 /* Handle superfluous braces around string cst as in
6571 char x[] = {"foo"}; */
6573 && constructor_type
6577 {
6582 }
6585 {
6588 }
6590 /* Ignore elements of a brace group if it is entirely superfluous
6591 and has already been diagnosed. */
6595 /* If we've exhausted any levels that didn't have braces,
6596 pop them now. */
6598 {
6606 constructor_index)))
6608 else
6610 }
6612 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6617 {
6619 {
6620 tree fieldtype;
6624 {
6627 }
6634 /* Accept a string constant to initialize a subarray. */
6640 /* Otherwise, if we have come to a subaggregate,
6641 and we don't have an element of its type, push into it. */
6647 {
6650 }
6653 {
6657 }
6658 else
6659 /* Do the bookkeeping for an element that was
6660 directly output as a constructor. */
6661 {
6662 /* For a record, keep track of end position of last field. */
6664 constructor_bit_index
6670 /* Skip any nameless bit fields. */
6674 constructor_unfilled_fields =
6676 }
6679 /* Skip any nameless bit fields at the beginning. */
6684 }
6686 {
6687 tree fieldtype;
6691 {
6694 }
6701 /* Warn that traditional C rejects initialization of unions.
6702 We skip the warning if the value is zero. This is done
6703 under the assumption that the zero initializer in user
6704 code appears conditioned on e.g. __STDC__ to avoid
6705 "missing initializer" warnings and relies on default
6706 initialization to zero in the traditional C case.
6707 We also skip the warning if the initializer is designated,
6708 again on the assumption that this must be conditional on
6709 __STDC__ anyway (and we've already complained about the
6710 member-designator already). */
6715 /* Accept a string constant to initialize a subarray. */
6721 /* Otherwise, if we have come to a subaggregate,
6722 and we don't have an element of its type, push into it. */
6728 {
6731 }
6734 {
6738 }
6739 else
6740 /* Do the bookkeeping for an element that was
6741 directly output as a constructor. */
6742 {
6745 }
6748 }
6750 {
6754 /* Accept a string constant to initialize a subarray. */
6760 /* Otherwise, if we have come to a subaggregate,
6761 and we don't have an element of its type, push into it. */
6767 {
6770 }
6775 {
6778 }
6780 /* Now output the actual element. */
6782 {
6786 }
6788 constructor_index
6792 /* If we are doing the bookkeeping for an element that was
6793 directly output as a constructor, we must update
6794 constructor_unfilled_index. */
6796 }
6798 /* Handle the sole element allowed in a braced initializer
6799 for a scalar variable. */
6801 {
6804 }
6805 else
6806 {
6810 }
6812 /* Handle range initializers either at this level or anywhere higher
6813 in the designator stack. */
6815 {
6822 {
6826 }
6830 {
6834 }
6841 {
6845 {
6848 }
6856 }
6861 }
6864 }
6867 }
6868 \f
6869 /* Build a simple asm-statement, from one string literal. */
6870 tree
6872 tree expr;
6873 {
6880 {
6881 tree stmt;
6887 NULL_TREE));
6890 }
6894 }
6896 /* Build an asm-statement, whose components are a CV_QUALIFIER, a
6897 STRING, some OUTPUTS, some INPUTS, and some CLOBBERS. */
6899 tree
6901 tree cv_qualifier;
6902 tree string;
6903 tree outputs;
6904 tree inputs;
6905 tree clobbers;
6906 {
6907 tree tail;
6912 {
6915 }
6919 {
6923 }
6925 /* We can remove output conversions that change the type,
6926 but not the mode. */
6928 {
6934 /* Allow conversions as LHS here. build_modify_expr as called below
6935 will do the right thing with them. */
6946 }
6948 /* Remove output conversions that change the type but not the mode. */
6950 {
6954 }
6956 /* Perform default conversions on array and function inputs.
6957 Don't do this for other types as it would screw up operands
6958 expected to be in memory. */
6964 }
6966 /* Expand an ASM statement with operands, handling output operands
6967 that are not variables or INDIRECT_REFS by transforming such
6968 cases into cases that expand_asm_operands can handle.
6970 Arguments are same as for expand_asm_operands. */
6972 void
6978 {
6981 /* o[I] is the place that output number I should be written. */
6983 tree tail;
6985 /* Record the contents of OUTPUTS before it is modified. */
6989 /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of
6990 OUTPUTS some trees for where the values were actually stored. */
6993 /* Copy all the intermediate outputs into the specified outputs. */
6995 {
6997 {
7002 /* Restore the original value so that it's correct the next
7003 time we expand this function. */
7005 }
7006 /* Detect modification of read-only values.
7007 (Otherwise done by build_modify_expr.) */
7008 else
7009 {
7017 }
7018 }
7020 /* Those MODIFY_EXPRs could do autoincrements. */
7022 }
7023 \f
7024 /* Expand a C `return' statement.
7025 RETVAL is the expression for what to return,
7026 or a null pointer for `return;' with no value. */
7028 tree
7030 tree retval;
7031 {
7038 {
7043 }
7045 {
7049 }
7050 else
7051 {
7055 tree inner;
7062 /* Strip any conversions, additions, and subtractions, and see if
7063 we are returning the address of a local variable. Warn if so. */
7065 {
7067 {
7074 /* If the second operand of the MINUS_EXPR has a pointer
7075 type (or is converted from it), this may be valid, so
7076 don't give a warning. */
7077 {
7091 }
7108 }
7111 }
7115 }
7118 }
7119 \f
7121 /* The SWITCH_STMT being built. */
7122 tree switch_stmt;
7123 /* A splay-tree mapping the low element of a case range to the high
7124 element, or NULL_TREE if there is no high element. Used to
7125 determine whether or not a new case label duplicates an old case
7126 label. We need a tree, rather than simply a hash table, because
7127 of the GNU case range extension. */
7128 splay_tree cases;
7129 /* The next node on the stack. */
7131 };
7133 /* A stack of the currently active switch statements. The innermost
7134 switch statement is on the top of the stack. There is no need to
7135 mark the stack for garbage collection because it is only active
7136 during the processing of the body of a function, and we never
7137 collect at that point. */
7141 /* Start a C switch statement, testing expression EXP. Return the new
7142 SWITCH_STMT. */
7144 tree
7146 tree exp;
7147 {
7149 tree type;
7153 {
7159 {
7162 }
7163 else
7164 {
7174 }
7175 }
7177 /* Add this new SWITCH_STMT to the stack. */
7185 }
7187 /* Process a case label. */
7189 tree
7191 tree low_value;
7192 tree high_value;
7193 {
7197 {
7203 }
7206 else
7210 }
7212 /* Finish the switch statement. */
7214 void
7216 {
7221 /* Pop the stack. */
7225 }