| blob | 76ebc3416d940accb317ad75a72a0c3f1607fbb1 |
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 /* Given a type, apply default promotions wrt unnamed function
177 arguments and return the new type. */
179 tree
181 tree type;
182 {
187 {
188 /* Preserve unsignedness if not really getting any wider. */
193 }
196 }
198 /* Return a variant of TYPE which has all the type qualifiers of LIKE
199 as well as those of TYPE. */
201 static tree
204 {
207 }
208 \f
209 /* Return the common type of two types.
210 We assume that comptypes has already been done and returned 1;
211 if that isn't so, this may crash. In particular, we assume that qualifiers
212 match.
214 This is the type for the result of most arithmetic operations
215 if the operands have the given two types. */
217 tree
220 {
223 tree attributes;
225 /* Save time if the two types are the same. */
229 /* If one type is nonsense, use the other. */
235 /* Merge the attributes. */
238 /* Treat an enum type as the unsigned integer type of the same width. */
248 /* If one type is complex, form the common type of the non-complex
249 components, then make that complex. Use T1 or T2 if it is the
250 required type. */
252 {
261 else
263 attributes);
264 }
267 {
270 /* If only one is real, use it as the result. */
278 /* Both real or both integers; use the one with greater precision. */
285 /* Same precision. Prefer longs to ints even when same size. */
290 attributes);
294 {
295 /* But preserve unsignedness from the other type,
296 since long cannot hold all the values of an unsigned int. */
299 else
302 }
304 /* Likewise, prefer long double to double even if same size. */
308 attributes);
310 /* Otherwise prefer the unsigned one. */
314 else
318 /* For two pointers, do this recursively on the target type,
319 and combine the qualifiers of the two types' targets. */
320 /* This code was turned off; I don't know why.
321 But ANSI C specifies doing this with the qualifiers.
322 So I turned it on again. */
323 {
333 }
334 #if 0
337 #endif
340 {
342 /* Save space: see if the result is identical to one of the args. */
347 /* Merge the element types, and have a size if either arg has one. */
350 }
353 /* Function types: prefer the one that specified arg types.
354 If both do, merge the arg types. Also merge the return types. */
355 {
363 /* Save space: see if the result is identical to one of the args. */
369 /* Simple way if one arg fails to specify argument types. */
371 {
374 }
376 {
379 }
381 /* If both args specify argument types, we must merge the two
382 lists, argument by argument. */
397 {
398 /* A null type means arg type is not specified.
399 Take whatever the other function type has. */
401 {
404 }
406 {
409 }
411 /* Given wait (union {union wait *u; int *i} *)
412 and wait (union wait *),
413 prefer union wait * as type of parm. */
416 {
417 tree memb;
421 {
426 }
427 }
430 {
431 tree memb;
435 {
440 }
441 }
443 parm_done: ;
444 }
449 /* ... falls through ... */
450 }
454 }
456 }
457 \f
458 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
459 or various other operations. Return 2 if they are compatible
460 but a warning may be needed if you use them together. */
462 int
465 {
470 /* Suppress errors caused by previously reported errors. */
476 /* If either type is the internal version of sizetype, return the
477 language version. */
486 /* Treat an enum type as the integer type of the same width and
487 signedness. */
497 /* Different classes of types can't be compatible. */
501 /* Qualifiers must match. */
506 /* Allow for two different type nodes which have essentially the same
507 definition. Note that we already checked for equality of the type
508 qualifiers (just above). */
513 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
517 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
521 {
532 {
539 /* Target types must match incl. qualifiers. */
544 /* Sizes must match unless one is missing or variable. */
551 d1_variable = (! d1_zero
554 d2_variable = (! d2_zero
568 }
577 }
579 }
581 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
582 ignoring their qualifiers. */
584 static int
587 {
590 /* Give maybe_objc_comptypes a crack at letting these types through. */
600 }
601 \f
602 /* Subroutines of `comptypes'. */
604 /* Return 1 if two function types F1 and F2 are compatible.
605 If either type specifies no argument types,
606 the other must specify a fixed number of self-promoting arg types.
607 Otherwise, if one type specifies only the number of arguments,
608 the other must specify that number of self-promoting arg types.
609 Otherwise, the argument types must match. */
611 static int
614 {
616 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
627 /* An unspecified parmlist matches any specified parmlist
628 whose argument types don't need default promotions. */
631 {
634 /* If one of these types comes from a non-prototype fn definition,
635 compare that with the other type's arglist.
636 If they don't match, ask for a warning (but no error). */
641 }
643 {
650 }
652 /* Both types have argument lists: compare them and propagate results. */
655 }
657 /* Check two lists of types for compatibility,
658 returning 0 for incompatible, 1 for compatible,
659 or 2 for compatible with warning. */
661 static int
664 {
665 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
670 {
673 /* If one list is shorter than the other,
674 they fail to match. */
677 /* A null pointer instead of a type
678 means there is supposed to be an argument
679 but nothing is specified about what type it has.
680 So match anything that self-promotes. */
682 {
685 }
687 {
690 }
693 {
694 /* Allow wait (union {union wait *u; int *i} *)
695 and wait (union wait *) to be compatible. */
702 {
703 tree memb;
710 }
717 {
718 tree memb;
725 }
726 else
728 }
730 /* comptypes said ok, but record if it said to warn. */
736 }
737 }
738 \f
739 /* Compute the value of the `sizeof' operator. */
741 tree
743 tree type;
744 {
746 tree size;
749 {
753 }
755 {
759 }
763 {
766 }
767 else
768 /* Convert in case a char is more than one unit. */
773 /* SIZE will have an integer type with TYPE_IS_SIZETYPE set.
774 TYPE_IS_SIZETYPE means that certain things (like overflow) will
775 never happen. However, this node should really have type
776 `size_t', which is just a typedef for an ordinary integer type. */
778 }
780 tree
782 tree type;
783 {
785 tree size;
791 else
792 /* Convert in case a char is more than one unit. */
797 /* SIZE will have an integer type with TYPE_IS_SIZETYPE set.
798 TYPE_IS_SIZETYPE means that certain things (like overflow) will
799 never happen. However, this node should really have type
800 `size_t', which is just a typedef for an ordinary integer type. */
802 }
804 /* Compute the size to increment a pointer by. */
806 tree
808 tree type;
809 {
816 {
819 }
821 /* Convert in case a char is more than one unit. */
825 }
826 \f
827 /* Return either DECL or its known constant value (if it has one). */
829 tree
831 tree decl;
832 {
834 in a place where a variable is invalid. */
840 /* This is invalid if initial value is not constant.
841 If it has either a function call, a memory reference,
842 or a variable, then re-evaluating it could give different results. */
844 /* Check for cases where this is sub-optimal, even though valid. */
848 }
850 /* Return either DECL or its known constant value (if it has one), but
851 return DECL if pedantic or DECL has mode BLKmode. This is for
852 bug-compatibility with the old behavior of decl_constant_value
853 (before GCC 3.0); every use of this function is a bug and it should
854 be removed before GCC 3.1. It is not appropriate to use pedantic
855 in a way that affects optimization, and BLKmode is probably not the
856 right test for avoiding misoptimizations either. */
858 static tree
860 tree decl;
861 {
864 else
866 }
869 /* Perform the default conversion of arrays and functions to pointers.
870 Return the result of converting EXP. For any other expression, just
871 return EXP. */
873 static tree
875 tree exp;
876 {
877 tree orig_exp;
882 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
883 an lvalue.
885 Do not use STRIP_NOPS here! It will remove conversions from pointer
886 to integer and cause infinite recursion. */
891 {
895 }
897 /* Preserve the original expression code. */
902 {
904 }
906 {
907 tree adr;
909 tree ptrtype;
915 {
918 }
921 restype
932 {
936 }
940 {
941 /* Before C99, non-lvalue arrays do not decay to pointers.
942 Normally, using such an array would be invalid; but it can
943 be used correctly inside sizeof or as a statement expression.
944 Thus, do not give an error here; an error will result later. */
946 }
951 {
952 /* ??? This is not really quite correct
953 in that the type of the operand of ADDR_EXPR
954 is not the target type of the type of the ADDR_EXPR itself.
955 Question is, can this lossage be avoided? */
962 }
963 /* This way is better for a COMPONENT_REF since it can
964 simplify the offset for a component. */
967 }
969 }
971 /* Perform default promotions for C data used in expressions.
972 Arrays and functions are converted to pointers;
973 enumeral types or short or char, to int.
974 In addition, manifest constants symbols are replaced by their values. */
976 tree
978 tree exp;
979 {
980 tree orig_exp;
987 /* Constants can be used directly unless they're not loadable. */
991 /* Replace a nonvolatile const static variable with its value unless
992 it is an array, in which case we must be sure that taking the
993 address of the array produces consistent results. */
995 {
998 }
1000 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
1001 an lvalue.
1003 Do not use STRIP_NOPS here! It will remove conversions from pointer
1004 to integer and cause infinite recursion. */
1011 /* Preserve the original expression code. */
1015 /* Normally convert enums to int,
1016 but convert wide enums to something wider. */
1018 {
1026 }
1030 /* If it's thinner than an int, promote it like a
1031 c_promoting_integer_type_p, otherwise leave it alone. */
1037 {
1038 /* Preserve unsignedness if not really getting any wider. */
1044 }
1047 {
1050 }
1052 }
1053 \f
1054 /* Look up COMPONENT in a structure or union DECL.
1056 If the component name is not found, returns NULL_TREE. Otherwise,
1057 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1058 stepping down the chain to the component, which is in the last
1059 TREE_VALUE of the list. Normally the list is of length one, but if
1060 the component is embedded within (nested) anonymous structures or
1061 unions, the list steps down the chain to the component. */
1063 static tree
1066 {
1068 tree field;
1070 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1071 to the field elements. Use a binary search on this array to quickly
1072 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1073 will always be set for structures which have many elements. */
1076 {
1084 {
1089 {
1090 /* Step through all anon unions in linear fashion. */
1092 {
1096 {
1101 }
1102 }
1104 /* Entire record is only anon unions. */
1108 /* Restart the binary search, with new lower bound. */
1110 }
1116 else
1118 }
1124 }
1125 else
1126 {
1128 {
1132 {
1137 }
1141 }
1145 }
1148 }
1150 /* Make an expression to refer to the COMPONENT field of
1151 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1153 tree
1156 {
1160 tree ref;
1162 /* If DATUM is a COMPOUND_EXPR, move our reference inside it.
1163 If pedantic ensure that the arguments are not lvalues; otherwise,
1164 if the component is an array, it would wrongly decay to a pointer in
1165 C89 mode.
1166 We cannot do this with a COND_EXPR, because in a conditional expression
1167 the default promotions are applied to both sides, and this would yield
1168 the wrong type of the result; for example, if the components have
1169 type "char". */
1171 {
1173 {
1177 }
1180 }
1182 /* See if there is a field or component with name COMPONENT. */
1185 {
1187 {
1190 }
1195 {
1200 }
1202 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1203 This might be better solved in future the way the C++ front
1204 end does it - by giving the anonymous entities each a
1205 separate name and type, and then have build_component_ref
1206 recursively call itself. We can't do that here. */
1208 {
1224 }
1227 }
1233 }
1234 \f
1235 /* Given an expression PTR for a pointer, return an expression
1236 for the value pointed to.
1237 ERRORSTRING is the name of the operator to appear in error messages. */
1239 tree
1241 tree ptr;
1243 {
1248 {
1250 && !flag_volatile
1254 else
1255 {
1260 {
1263 }
1267 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1268 so that we get the proper error message if the result is used
1269 to assign to. Also, &* is supposed to be a no-op.
1270 And ANSI C seems to specify that the type of the result
1271 should be the const type. */
1272 /* A de-reference of a pointer to const is not a const. It is valid
1273 to change it via some other pointer. */
1279 }
1280 }
1284 }
1286 /* This handles expressions of the form "a[i]", which denotes
1287 an array reference.
1289 This is logically equivalent in C to *(a+i), but we may do it differently.
1290 If A is a variable or a member, we generate a primitive ARRAY_REF.
1291 This avoids forcing the array out of registers, and can work on
1292 arrays that are not lvalues (for example, members of structures returned
1293 by functions). */
1295 tree
1298 {
1300 {
1303 }
1311 {
1314 /* Subscripting with type char is likely to lose
1315 on a machine where chars are signed.
1316 So warn on any machine, but optionally.
1317 Don't warn for unsigned char since that type is safe.
1318 Don't warn for signed char because anyone who uses that
1319 must have done so deliberately. */
1324 /* Apply default promotions *after* noticing character types. */
1327 /* Require integer *after* promotion, for sake of enums. */
1329 {
1332 }
1334 /* An array that is indexed by a non-constant
1335 cannot be stored in a register; we must be able to do
1336 address arithmetic on its address.
1337 Likewise an array of elements of variable size. */
1341 {
1344 }
1345 /* An array that is indexed by a constant value which is not within
1346 the array bounds cannot be stored in a register either; because we
1347 would get a crash in store_bit_field/extract_bit_field when trying
1348 to access a non-existent part of the register. */
1352 {
1355 }
1358 {
1366 }
1370 /* Array ref is const/volatile if the array elements are
1371 or if the array is. */
1380 /* This was added by rms on 16 Nov 91.
1381 It fixes vol struct foo *a; a->elts[1]
1382 in an inline function.
1383 Hope it doesn't break something else. */
1386 }
1388 {
1392 /* Do the same warning check as above, but only on the part that's
1393 syntactically the index and only if it is also semantically
1394 the index. */
1400 /* Put the integer in IND to simplify error checking. */
1402 {
1406 }
1413 {
1416 }
1418 {
1421 }
1425 }
1426 }
1427 \f
1428 /* Build an external reference to identifier ID. FUN indicates
1429 whether this will be used for a function call. */
1430 tree
1432 tree id;
1434 {
1435 tree ref;
1443 {
1447 {
1449 /* Ordinary implicit function declaration. */
1451 else
1452 {
1453 /* Implicit declaration of built-in function. Don't
1454 change the built-in declaration, but don't let this
1455 go by silently, either. */
1458 /* only issue this warning once */
1461 }
1462 }
1463 else
1464 {
1465 /* Reference to undeclared variable, including reference to
1466 builtin outside of function-call context. */
1470 else
1471 {
1474 {
1479 {
1483 }
1484 }
1487 }
1489 }
1490 }
1491 else
1492 {
1493 /* Properly declared variable or function reference. */
1497 {
1501 }
1502 else
1504 }
1513 {
1516 }
1519 }
1521 /* Build a function call to function FUNCTION with parameters PARAMS.
1522 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1523 TREE_VALUE of each node is a parameter-expression.
1524 FUNCTION's data type may be a function type or a pointer-to-function. */
1526 tree
1529 {
1531 tree coerced_params;
1534 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1537 /* Convert anything with function type to a pointer-to-function. */
1539 {
1543 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1544 (because calling an inline function does not mean the function
1545 needs to be separately compiled). */
1551 }
1552 else
1562 {
1565 }
1570 /* fntype now gets the type of function pointed to. */
1573 /* Convert the parameters to the types declared in the
1574 function prototype, or apply default promotions. */
1576 coerced_params
1579 /* Check that the arguments to the function are valid. */
1583 /* Recognize certain built-in functions so we can make tree-codes
1584 other than CALL_EXPR. We do this when it enables fold-const.c
1585 to do something useful. */
1590 {
1595 }
1605 }
1606 \f
1607 /* Convert the argument expressions in the list VALUES
1608 to the types in the list TYPELIST. The result is a list of converted
1609 argument expressions.
1611 If TYPELIST is exhausted, or when an element has NULL as its type,
1612 perform the default conversions.
1614 PARMLIST is the chain of parm decls for the function being called.
1615 It may be 0, if that info is not available.
1616 It is used only for generating error messages.
1618 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1620 This is also where warnings about wrong number of args are generated.
1622 Both VALUES and the returned value are chains of TREE_LIST nodes
1623 with the elements of the list in the TREE_VALUE slots of those nodes. */
1625 static tree
1628 {
1633 /* Scan the given expressions and types, producing individual
1634 converted arguments and pushing them on RESULT in reverse order. */
1637 valtail;
1639 {
1644 {
1648 else
1651 }
1653 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1654 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1655 to convert automatically to a pointer. */
1664 {
1665 /* Formal parm type is specified by a function prototype. */
1666 tree parmval;
1669 {
1672 }
1673 else
1674 {
1675 /* Optionally warn about conversions that
1676 differ from the default conversions. */
1678 {
1683 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1686 warn_for_assignment ("%s as integer rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1689 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1692 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1695 warn_for_assignment ("%s as complex rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1698 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1699 /* ??? At some point, messages should be written about
1700 conversions between complex types, but that's too messy
1701 to do now. */
1704 {
1705 /* Warn if any argument is passed as `float',
1706 since without a prototype it would be `double'. */
1708 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1709 }
1710 /* Detect integer changing in width or signedness.
1711 These warnings are only activated with
1712 -Wconversion, not with -Wtraditional. */
1715 {
1722 /* No warning if function asks for enum
1723 and the actual arg is that enum type. */
1724 ;
1726 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1728 ;
1729 /* Don't complain if the formal parameter type
1730 is an enum, because we can't tell now whether
1731 the value was an enum--even the same enum. */
1733 ;
1736 /* Change in signedness doesn't matter
1737 if a constant value is unaffected. */
1738 ;
1739 /* Likewise for a constant in a NOP_EXPR. */
1743 ;
1748 /* Change in signedness doesn't matter
1749 if an enum value is unaffected. */
1750 ;
1751 #endif
1752 /* If the value is extended from a narrower
1753 unsigned type, it doesn't matter whether we
1754 pass it as signed or unsigned; the value
1755 certainly is the same either way. */
1758 ;
1761 else
1763 }
1764 }
1774 }
1776 }
1780 /* Convert `float' to `double'. */
1782 else
1783 /* Convert `short' and `char' to full-size `int'. */
1788 }
1791 {
1795 else
1797 }
1800 }
1801 \f
1802 /* This is the entry point used by the parser
1803 for binary operators in the input.
1804 In addition to constructing the expression,
1805 we check for operands that were written with other binary operators
1806 in a way that is likely to confuse the user. */
1808 tree
1812 {
1829 /* Check for cases such as x+y<<z which users are likely
1830 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1831 is cleared to prevent these warnings. */
1833 {
1835 {
1839 }
1842 {
1846 }
1849 {
1855 /* Check cases like x|y==z */
1858 }
1861 {
1867 /* Check cases like x^y==z */
1870 }
1873 {
1877 /* Check cases like x&y==z */
1880 }
1881 }
1883 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1894 /* Record the code that was specified in the source,
1895 for the sake of warnings about confusing nesting. */
1898 else
1899 {
1901 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1902 so that convert_for_assignment wouldn't strip it.
1903 That way, we got warnings for things like p = (1 - 1).
1904 But it turns out we should not get those warnings. */
1908 }
1911 }
1913 /* Build a binary-operation expression without default conversions.
1914 CODE is the kind of expression to build.
1915 This function differs from `build' in several ways:
1916 the data type of the result is computed and recorded in it,
1917 warnings are generated if arg data types are invalid,
1918 special handling for addition and subtraction of pointers is known,
1919 and some optimization is done (operations on narrow ints
1920 are done in the narrower type when that gives the same result).
1921 Constant folding is also done before the result is returned.
1923 Note that the operands will never have enumeral types, or function
1924 or array types, because either they will have the default conversions
1925 performed or they have both just been converted to some other type in which
1926 the arithmetic is to be done. */
1928 tree
1933 {
1938 /* Expression code to give to the expression when it is built.
1939 Normally this is CODE, which is what the caller asked for,
1940 but in some special cases we change it. */
1943 /* Data type in which the computation is to be performed.
1944 In the simplest cases this is the common type of the arguments. */
1947 /* Nonzero means operands have already been type-converted
1948 in whatever way is necessary.
1949 Zero means they need to be converted to RESULT_TYPE. */
1952 /* Nonzero means create the expression with this type, rather than
1953 RESULT_TYPE. */
1956 /* Nonzero means after finally constructing the expression
1957 convert it to this type. */
1960 /* Nonzero if this is an operation like MIN or MAX which can
1961 safely be computed in short if both args are promoted shorts.
1962 Also implies COMMON.
1963 -1 indicates a bitwise operation; this makes a difference
1964 in the exact conditions for when it is safe to do the operation
1965 in a narrower mode. */
1968 /* Nonzero if this is a comparison operation;
1969 if both args are promoted shorts, compare the original shorts.
1970 Also implies COMMON. */
1973 /* Nonzero if this is a right-shift operation, which can be computed on the
1974 original short and then promoted if the operand is a promoted short. */
1977 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1981 {
1984 }
1985 else
1986 {
1989 }
1994 /* The expression codes of the data types of the arguments tell us
1995 whether the arguments are integers, floating, pointers, etc. */
1999 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2003 /* If an error was already reported for one of the arguments,
2004 avoid reporting another error. */
2010 {
2012 /* Handle the pointer + int case. */
2017 else
2022 /* Subtraction of two similar pointers.
2023 We must subtract them as integers, then divide by object size. */
2027 /* Handle pointer minus int. Just like pointer plus int. */
2030 else
2043 /* Floating point division by zero is a legitimate way to obtain
2044 infinities and NaNs. */
2052 {
2055 else
2056 /* Although it would be tempting to shorten always here, that
2057 loses on some targets, since the modulo instruction is
2058 undefined if the quotient can't be represented in the
2059 computation mode. We shorten only if unsigned or if
2060 dividing by something we know != -1. */
2065 }
2082 {
2083 /* Although it would be tempting to shorten always here, that loses
2084 on some targets, since the modulo instruction is undefined if the
2085 quotient can't be represented in the computation mode. We shorten
2086 only if unsigned or if dividing by something we know != -1. */
2091 }
2103 {
2104 /* Result of these operations is always an int,
2105 but that does not mean the operands should be
2106 converted to ints! */
2111 }
2114 /* Shift operations: result has same type as first operand;
2115 always convert second operand to int.
2116 Also set SHORT_SHIFT if shifting rightward. */
2120 {
2122 {
2125 else
2126 {
2132 }
2133 }
2135 /* Use the type of the value to be shifted. */
2137 /* Convert the shift-count to an integer, regardless of size
2138 of value being shifted. */
2141 /* Avoid converting op1 to result_type later. */
2143 }
2148 {
2150 {
2156 }
2158 /* Use the type of the value to be shifted. */
2160 /* Convert the shift-count to an integer, regardless of size
2161 of value being shifted. */
2164 /* Avoid converting op1 to result_type later. */
2166 }
2172 {
2174 {
2179 }
2181 /* Use the type of the value to be shifted. */
2183 /* Convert the shift-count to an integer, regardless of size
2184 of value being shifted. */
2187 /* Avoid converting op1 to result_type later. */
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 {
2243 }
2245 {
2248 }
2257 {
2259 {
2264 }
2265 else
2266 {
2269 }
2270 }
2282 {
2284 {
2292 }
2293 else
2294 {
2297 }
2298 }
2301 {
2305 }
2308 {
2312 }
2314 {
2317 }
2319 {
2322 }
2334 {
2337 }
2343 }
2346 &&
2348 {
2354 /* For certain operations (which identify themselves by shorten != 0)
2355 if both args were extended from the same smaller type,
2356 do the arithmetic in that type and then extend.
2358 shorten !=0 and !=1 indicates a bitwise operation.
2359 For them, this optimization is safe only if
2360 both args are zero-extended or both are sign-extended.
2361 Otherwise, we might change the result.
2362 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2363 but calculated in (unsigned short) it would be (unsigned short)-1. */
2366 {
2370 /* UNS is 1 if the operation to be done is an unsigned one. */
2372 tree type;
2376 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2377 but it *requires* conversion to FINAL_TYPE. */
2388 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2390 /* For bitwise operations, signedness of nominal type
2391 does not matter. Consider only how operands were extended. */
2395 /* Note that in all three cases below we refrain from optimizing
2396 an unsigned operation on sign-extended args.
2397 That would not be valid. */
2399 /* Both args variable: if both extended in same way
2400 from same width, do it in that width.
2401 Do it unsigned if args were zero-extended. */
2408 result_type
2409 = c_common_signed_or_unsigned_type
2415 && (type
2424 && (type
2429 }
2431 /* Shifts can be shortened if shifting right. */
2434 {
2444 /* We can shorten only if the shift count is less than the
2445 number of bits in the smaller type size. */
2447 /* We cannot drop an unsigned shift after sign-extension. */
2449 {
2450 /* Do an unsigned shift if the operand was zero-extended. */
2451 result_type
2454 /* Convert value-to-be-shifted to that type. */
2458 }
2459 }
2461 /* Comparison operations are shortened too but differently.
2462 They identify themselves by setting short_compare = 1. */
2465 {
2466 /* Don't write &op0, etc., because that would prevent op0
2467 from being kept in a register.
2468 Instead, make copies of the our local variables and
2469 pass the copies by reference, then copy them back afterward. */
2472 tree val
2484 {
2496 /* Give warnings for comparisons between signed and unsigned
2497 quantities that may fail.
2499 Do the checking based on the original operand trees, so that
2500 casts will be considered, but default promotions won't be.
2502 Do not warn if the comparison is being done in a signed type,
2503 since the signed type will only be chosen if it can represent
2504 all the values of the unsigned type. */
2507 /* Do not warn if both operands are the same signedness. */
2510 else
2511 {
2516 else
2519 /* Do not warn if the signed quantity is an
2520 unsuffixed integer literal (or some static
2521 constant expression involving such literals or a
2522 conditional expression involving such literals)
2523 and it is non-negative. */
2526 /* Do not warn if the comparison is an equality operation,
2527 the unsigned quantity is an integral constant, and it
2528 would fit in the result if the result were signed. */
2531 && int_fits_type_p
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. */
2539 && int_fits_type_p
2543 else
2545 }
2547 /* Warn if two unsigned values are being compared in a size
2548 larger than their original size, and one (and only one) is the
2549 result of a `~' operator. This comparison will always fail.
2551 Also warn if one operand is a constant, and the constant
2552 does not have all bits set that are set in the ~ operand
2553 when it is extended. */
2557 {
2561 else
2566 {
2567 tree primop;
2572 {
2576 }
2577 else
2578 {
2582 }
2587 {
2591 }
2592 }
2599 }
2600 }
2601 }
2602 }
2604 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2605 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2606 Then the expression will be built.
2607 It will be given type FINAL_TYPE if that is nonzero;
2608 otherwise, it will be given type RESULT_TYPE. */
2611 {
2614 }
2617 {
2622 }
2627 {
2629 tree folded;
2637 }
2638 }
2639 \f
2640 /* Return a tree for the difference of pointers OP0 and OP1.
2641 The resulting tree has type int. */
2643 static tree
2646 {
2655 {
2660 }
2662 /* If the conversion to ptrdiff_type does anything like widening or
2663 converting a partial to an integral mode, we get a convert_expression
2664 that is in the way to do any simplifications.
2665 (fold-const.c doesn't know that the extra bits won't be needed.
2666 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2667 different mode in place.)
2668 So first try to find a common term here 'by hand'; we want to cover
2669 at least the cases that occur in legal static initializers. */
2674 {
2677 }
2678 else
2682 {
2685 }
2686 else
2690 {
2693 }
2696 /* First do the subtraction as integers;
2697 then drop through to build the divide operator.
2698 Do not do default conversions on the minus operator
2699 in case restype is a short type. */
2703 /* This generates an error if op1 is pointer to incomplete type. */
2707 /* This generates an error if op0 is pointer to incomplete type. */
2710 /* Divide by the size, in easiest possible way. */
2718 }
2719 \f
2720 /* Construct and perhaps optimize a tree representation
2721 for a unary operation. CODE, a tree_code, specifies the operation
2722 and XARG is the operand.
2723 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2724 the default promotions (such as from short to int).
2725 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2726 allows non-lvalues; this is only used to handle conversion of non-lvalue
2727 arrays to pointers in C99. */
2729 tree
2732 tree xarg;
2734 {
2735 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2739 tree val;
2748 {
2750 /* This is used for unary plus, because a CONVERT_EXPR
2751 is enough to prevent anybody from looking inside for
2752 associativity, but won't generate any code. */
2755 {
2758 }
2767 {
2770 }
2777 {
2783 }
2785 {
2788 }
2796 {
2799 }
2805 /* Conjugating a real value is a no-op, but allow it anyway. */
2808 {
2811 }
2820 /* These will convert to a pointer. */
2822 {
2825 }
2837 else
2845 else
2852 /* Handle complex lvalues (when permitted)
2853 by reduction to simpler cases. */
2859 /* Increment or decrement the real part of the value,
2860 and don't change the imaginary part. */
2862 {
2873 }
2875 /* Report invalid types. */
2879 {
2882 else
2886 }
2888 {
2889 tree inc;
2895 /* Compute the increment. */
2898 {
2899 /* If pointer target is an undefined struct,
2900 we just cannot know how to do the arithmetic. */
2902 {
2905 else
2907 }
2911 {
2914 else
2916 }
2919 }
2920 else
2925 /* Handle incrementing a cast-expression. */
2929 {
2938 /* If the real type has the same machine representation
2939 as the type it is cast to, we can make better output
2940 by adding directly to the inside of the cast. */
2946 else
2947 {
2951 else
2952 {
2956 else
2965 }
2968 }
2973 }
2974 give_up:
2976 /* Complain about anything else that is not a true lvalue. */
2983 /* Report a read-only lvalue. */
2992 else
2999 }
3002 /* Note that this operation never does default_conversion. */
3004 /* Let &* cancel out to simplify resulting code. */
3006 {
3007 /* Don't let this be an lvalue. */
3011 }
3013 /* For &x[y], return x+y */
3015 {
3020 }
3022 /* Handle complex lvalues (when permitted)
3023 by reduction to simpler cases. */
3029 float f; *&(int)f = 3.4 stores in int format
3030 whereas (int)f = 3.4 stores in float format. */
3031 /* Address of a cast is just a cast of the address
3032 of the operand of the cast. */
3034 {
3047 }
3048 #endif
3050 /* Anything not already handled and not a true memory reference
3051 or a non-lvalue array is an error. */
3056 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3059 /* If the lvalue is const or volatile, merge that into the type
3060 to which the address will point. Note that you can't get a
3061 restricted pointer by taking the address of something, so we
3062 only have to deal with `const' and `volatile' here. */
3074 {
3075 tree addr;
3078 {
3084 {
3088 }
3093 }
3094 else
3097 /* Address of a static or external variable or
3098 file-scope function counts as a constant. */
3104 }
3108 }
3113 }
3115 #if 0
3116 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3117 convert ARG with the same conversions in the same order
3118 and return the result. */
3120 static tree
3122 tree conversions;
3123 tree arg;
3124 {
3126 {
3136 arg));
3140 }
3141 }
3144 /* Return nonzero if REF is an lvalue valid for this language.
3145 Lvalues can be assigned, unless their type has TYPE_READONLY.
3146 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3148 int
3150 tree ref;
3151 {
3155 {
3180 }
3181 }
3183 /* Return nonzero if REF is an lvalue valid for this language;
3184 otherwise, print an error message and return zero. */
3186 int
3188 tree ref;
3190 {
3197 }
3199 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3200 for certain kinds of expressions which are not really lvalues
3201 but which we can accept as lvalues. If FLAG is nonzero, then
3202 non-lvalues are OK since we may be converting a non-lvalue array to
3203 a pointer in C99.
3205 If ARG is not a kind of expression we can handle, return zero. */
3207 static tree
3210 tree arg;
3212 {
3213 /* Handle (a, b) used as an "lvalue". */
3215 {
3218 /* If this returns a function type, it isn't really being used as
3219 an lvalue, so don't issue a warning about it. */
3225 }
3227 /* Handle (a ? b : c) used as an "lvalue". */
3229 {
3239 }
3242 }
3244 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3245 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3247 static void
3250 {
3253 {
3263 }
3264 }
3265 \f
3266 /* Warn about storing in something that is `const'. */
3268 void
3270 tree arg;
3272 {
3274 {
3277 else
3280 }
3284 else
3286 }
3287 \f
3288 /* Mark EXP saying that we need to be able to take the
3289 address of it; it should not be allocated in a register.
3290 Returns true if successful. */
3292 bool
3294 tree exp;
3295 {
3300 {
3303 {
3307 }
3309 /* ... fall through ... */
3329 {
3331 {
3335 }
3338 }
3340 {
3342 {
3346 }
3348 /* If we are making this addressable due to its having
3349 volatile components, give a different error message. Also
3350 handle the case of an unnamed parameter by not trying
3351 to give the name. */
3354 {
3357 }
3361 }
3364 /* drops in */
3370 #endif
3374 }
3375 }
3376 \f
3377 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3379 tree
3382 {
3383 tree type1;
3384 tree type2;
3393 /* Don't promote the operands separately if they promote
3394 the same way. Return the unpromoted type and let the combined
3395 value get promoted if necessary. */
3401 {
3406 }
3407 #endif
3409 /* Promote both alternatives. */
3426 /* Quickly detect the usual case where op1 and op2 have the same type
3427 after promotion. */
3429 {
3432 else
3434 }
3439 {
3442 /* If -Wsign-compare, warn here if type1 and type2 have
3443 different signedness. We'll promote the signed to unsigned
3444 and later code won't know it used to be different.
3445 Do this check on the original types, so that explicit casts
3446 will be considered, but default promotions won't. */
3449 {
3454 {
3455 /* Do not warn if the result type is signed, since the
3456 signed type will only be chosen if it can represent
3457 all the values of the unsigned type. */
3460 /* Do not warn if the signed quantity is an unsuffixed
3461 integer literal (or some static constant expression
3462 involving such literals) and it is non-negative. */
3466 else
3468 }
3469 }
3470 }
3472 {
3476 }
3478 {
3488 {
3493 }
3495 {
3500 }
3501 else
3502 {
3505 }
3506 }
3508 {
3511 else
3512 {
3514 }
3516 }
3518 {
3521 else
3522 {
3524 }
3526 }
3529 {
3532 else
3533 {
3536 }
3537 }
3539 /* Merge const and volatile flags of the incoming types. */
3540 result_type
3554 }
3555 \f
3556 /* Given a list of expressions, return a compound expression
3557 that performs them all and returns the value of the last of them. */
3559 tree
3561 tree list;
3562 {
3564 }
3566 static tree
3568 tree list;
3570 {
3571 tree rest;
3574 {
3575 /* Convert arrays and functions to pointers when there
3576 really is a comma operator. */
3582 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3584 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3587 #endif
3589 /* Don't let (0, 0) be null pointer constant. */
3593 }
3598 {
3599 /* The left-hand operand of a comma expression is like an expression
3600 statement: with -W or -Wunused, we should warn if it doesn't have
3601 any side-effects, unless it was explicitly cast to (void). */
3607 /* When pedantic, a compound expression can be neither an lvalue
3608 nor an integer constant expression. */
3611 }
3613 /* With -Wunused, we should also warn if the left-hand operand does have
3614 side-effects, but computes a value which is not used. For example, in
3615 `foo() + bar(), baz()' the result of the `+' operator is not used,
3616 so we should issue a warning. */
3621 }
3623 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3625 tree
3627 tree type;
3628 tree expr;
3629 {
3636 #if 0
3637 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3640 #endif
3643 {
3646 }
3649 {
3652 }
3655 {
3657 {
3661 }
3662 }
3664 {
3665 tree field;
3674 {
3676 tree t;
3681 {
3684 else
3686 }
3687 else
3693 }
3696 }
3697 else
3698 {
3701 /* If casting to void, avoid the error that would come
3702 from default_conversion in the case of a non-lvalue array. */
3706 /* Convert functions and arrays to pointers,
3707 but don't convert any other types. */
3711 /* Optionally warn about potentially worrisome casts. */
3716 {
3722 /* Check that the qualifiers on IN_TYPE are a superset of
3723 the qualifiers of IN_OTYPE. The outermost level of
3724 POINTER_TYPE nodes is uninteresting and we stop as soon
3725 as we hit a non-POINTER_TYPE node on either type. */
3726 do
3727 {
3731 /* GNU C allows cv-qualified function types. 'const'
3732 means the function is very pure, 'volatile' means it
3733 can't return. We need to warn when such qualifiers
3734 are added, not when they're taken away. */
3738 else
3740 }
3748 /* There are qualifiers present in IN_OTYPE that are not
3749 present in IN_TYPE. */
3751 }
3753 /* Warn about possible alignment problems. */
3759 /* Don't warn about opaque types, where the actual alignment
3760 restriction is unknown. */
3781 /* Don't warn about converting any constant. */
3788 /* Ignore any integer overflow caused by the cast. */
3790 {
3793 }
3794 }
3796 /* Pedantically, don't let (void *) (FOO *) 0 be a null pointer constant. */
3802 /* If pedantic, don't let a cast be an lvalue. */
3807 }
3809 /* Interpret a cast of expression EXPR to type TYPE. */
3810 tree
3813 {
3816 /* This avoids warnings about unprototyped casts on
3817 integers. E.g. "#define SIG_DFL (void(*)())0". */
3824 }
3826 \f
3827 /* Build an assignment expression of lvalue LHS from value RHS.
3828 MODIFYCODE is the code for a binary operator that we use
3829 to combine the old value of LHS with RHS to get the new value.
3830 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3832 tree
3836 {
3837 tree result;
3838 tree newrhs;
3842 /* Types that aren't fully specified cannot be used in assignments. */
3845 /* Avoid duplicate error messages from operands that had errors. */
3849 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3850 /* Do not use STRIP_NOPS here. We do not want an enumerator
3851 whose value is 0 to count as a null pointer constant. */
3857 /* Handle control structure constructs used as "lvalues". */
3860 {
3861 /* Handle (a, b) used as an "lvalue". */
3870 /* Handle (a ? b : c) used as an "lvalue". */
3874 {
3875 /* Produce (a ? (b = rhs) : (c = rhs))
3876 except that the RHS goes through a save-expr
3877 so the code to compute it is only emitted once. */
3878 tree cond
3886 /* Make sure the code to compute the rhs comes out
3887 before the split. */
3889 /* But cast it to void to avoid an "unused" error. */
3891 }
3894 }
3896 /* If a binary op has been requested, combine the old LHS value with the RHS
3897 producing the value we should actually store into the LHS. */
3900 {
3903 }
3905 /* Handle a cast used as an "lvalue".
3906 We have already performed any binary operator using the value as cast.
3907 Now convert the result to the cast type of the lhs,
3908 and then true type of the lhs and store it there;
3909 then convert result back to the cast type to be the value
3910 of the assignment. */
3913 {
3922 {
3924 tree result;
3932 }
3936 }
3938 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3939 Reject anything strange now. */
3944 /* Warn about storing in something that is `const'. */
3952 /* If storing into a structure or union member,
3953 it has probably been given type `int'.
3954 Compute the type that would go with
3955 the actual amount of storage the member occupies. */
3964 /* If storing in a field that is in actuality a short or narrower than one,
3965 we must store in the field in its actual type. */
3968 {
3971 }
3973 /* Convert new value to destination type. */
3980 /* Scan operands */
3985 /* If we got the LHS in a different type for storing in,
3986 convert the result back to the nominal type of LHS
3987 so that the value we return always has the same type
3988 as the LHS argument. */
3994 }
3995 \f
3996 /* Convert value RHS to type TYPE as preparation for an assignment
3997 to an lvalue of type TYPE.
3998 The real work of conversion is done by `convert'.
3999 The purpose of this function is to generate error messages
4000 for assignments that are not allowed in C.
4001 ERRTYPE is a string to use in error messages:
4002 "assignment", "return", etc. If it is null, this is parameter passing
4003 for a function call (and different error messages are output).
4005 FUNNAME is the name of the function being called,
4006 as an IDENTIFIER_NODE, or null.
4007 PARMNUM is the number of the argument, for printing in error messages. */
4009 static tree
4015 {
4017 tree rhstype;
4020 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4021 /* Do not use STRIP_NOPS here. We do not want an enumerator
4022 whose value is 0 to count as a null pointer constant. */
4039 {
4041 /* Check for Objective-C protocols. This will issue a warning if
4042 there are protocol violations. No need to use the return value. */
4045 }
4048 {
4051 }
4052 /* A type converts to a reference to it.
4053 This code doesn't fully support references, it's just for the
4054 special case of va_start and va_copy. */
4057 {
4059 {
4062 }
4067 /* We already know that these two types are compatible, but they
4068 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4069 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4070 likely to be va_list, a typedef to __builtin_va_list, which
4071 is different enough that it will cause problems later. */
4077 }
4078 /* Arithmetic types all interconvert, and enum is treated like int. */
4087 /* Conversion to a transparent union from its member types.
4088 This applies only to function arguments. */
4090 {
4091 tree memb_types;
4096 {
4107 {
4111 /* Any non-function converts to a [const][volatile] void *
4112 and vice versa; otherwise, targets must be the same.
4113 Meanwhile, the lhs target must have all the qualifiers of
4114 the rhs. */
4117 {
4118 /* If this type won't generate any warnings, use it. */
4128 /* Keep looking for a better type, but remember this one. */
4131 }
4132 }
4134 /* Can convert integer zero to any pointer type. */
4138 {
4141 }
4142 }
4145 {
4147 {
4148 /* We have only a marginally acceptable member type;
4149 it needs a warning. */
4153 /* Const and volatile mean something different for function
4154 types, so the usual warnings are not appropriate. */
4157 {
4158 /* Because const and volatile on functions are
4159 restrictions that say the function will not do
4160 certain things, it is okay to use a const or volatile
4161 function where an ordinary one is wanted, but not
4162 vice-versa. */
4166 }
4170 parmnum);
4171 }
4177 }
4178 }
4180 /* Conversions among pointers */
4183 {
4187 /* Any non-function converts to a [const][volatile] void *
4188 and vice versa; otherwise, targets must be the same.
4189 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4194 {
4197 ||
4199 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4200 which are not ANSI null ptr constants. */
4205 /* Const and volatile mean something different for function types,
4206 so the usual warnings are not appropriate. */
4209 {
4213 /* If this is not a case of ignoring a mismatch in signedness,
4214 no warning. */
4217 ;
4218 /* If there is a mismatch, do warn. */
4222 }
4225 {
4226 /* Because const and volatile on functions are restrictions
4227 that say the function will not do certain things,
4228 it is okay to use a const or volatile function
4229 where an ordinary one is wanted, but not vice-versa. */
4233 }
4234 }
4235 else
4239 }
4241 {
4242 /* An explicit constant 0 can convert to a pointer,
4243 or one that results from arithmetic, even including
4244 a cast to integer type. */
4246 &&
4251 {
4255 }
4257 }
4259 {
4263 }
4268 {
4270 {
4276 else
4279 }
4280 else
4282 parmnum);
4283 }
4284 else
4288 }
4290 /* Convert VALUE for assignment into inlined parameter PARM. */
4292 tree
4295 {
4298 /* If FN was prototyped, the value has been converted already
4299 in convert_arguments. */
4312 }
4314 /* Print a warning using MSGID.
4315 It gets OPNAME as its one parameter.
4316 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4317 FUNCTION and ARGNUM are handled specially if we are building an
4318 Objective-C selector. */
4320 static void
4324 tree function;
4326 {
4328 {
4333 {
4336 }
4338 {
4339 /* Function name is known; supply it. */
4346 }
4347 else
4348 {
4349 /* Function name unknown (call through ptr); just give arg number. */
4353 }
4355 }
4357 }
4358 \f
4359 /* If VALUE is a compound expr all of whose expressions are constant, then
4360 return its value. Otherwise, return error_mark_node.
4362 This is for handling COMPOUND_EXPRs as initializer elements
4363 which is allowed with a warning when -pedantic is specified. */
4365 static tree
4367 tree value;
4368 tree endtype;
4369 {
4371 {
4376 endtype);
4377 }
4381 else
4383 }
4384 \f
4385 /* Perform appropriate conversions on the initial value of a variable,
4386 store it in the declaration DECL,
4387 and print any error messages that are appropriate.
4388 If the init is invalid, store an ERROR_MARK. */
4390 void
4393 {
4396 /* If variable's type was invalidly declared, just ignore it. */
4402 /* Digest the specified initializer into an expression. */
4406 /* Store the expression if valid; else report error. */
4408 #if 0
4409 /* Note that this is the only place we can detect the error
4410 in a case such as struct foo bar = (struct foo) { x, y };
4411 where there is one initial value which is a constructor expression. */
4413 ;
4415 {
4418 }
4421 {
4424 }
4425 else
4426 {
4428 {
4433 }
4434 }
4435 #endif
4443 /* ANSI wants warnings about out-of-range constant initializers. */
4447 /* Check if we need to set array size from compound literal size. */
4451 {
4459 {
4463 {
4464 /* For int foo[] = (int [3]){1}; we need to set array size
4465 now since later on array initializer will be just the
4466 brace enclosed list of the compound literal. */
4470 }
4471 }
4472 }
4473 }
4474 \f
4475 /* Methods for storing and printing names for error messages. */
4477 /* Implement a spelling stack that allows components of a name to be pushed
4478 and popped. Each element on the stack is this structure. */
4480 struct spelling
4481 {
4483 union
4484 {
4488 };
4490 #define SPELLING_STRING 1
4491 #define SPELLING_MEMBER 2
4492 #define SPELLING_BOUNDS 3
4498 /* Macros to save and restore the spelling stack around push_... functions.
4499 Alternative to SAVE_SPELLING_STACK. */
4501 #define SPELLING_DEPTH() (spelling - spelling_base)
4502 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4504 /* Save and restore the spelling stack around arbitrary C code. */
4506 #define SAVE_SPELLING_DEPTH(code) \
4507 { \
4508 int __depth = SPELLING_DEPTH (); \
4509 code; \
4510 RESTORE_SPELLING_DEPTH (__depth); \
4511 }
4513 /* Push an element on the spelling stack with type KIND and assign VALUE
4514 to MEMBER. */
4516 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4517 { \
4518 int depth = SPELLING_DEPTH (); \
4519 \
4520 if (depth >= spelling_size) \
4521 { \
4522 spelling_size += 10; \
4523 if (spelling_base == 0) \
4524 spelling_base \
4525 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4526 else \
4527 spelling_base \
4528 = (struct spelling *) xrealloc (spelling_base, \
4529 spelling_size * sizeof (struct spelling)); \
4530 RESTORE_SPELLING_DEPTH (depth); \
4531 } \
4532 \
4533 spelling->kind = (KIND); \
4534 spelling->MEMBER = (VALUE); \
4535 spelling++; \
4536 }
4538 /* Push STRING on the stack. Printed literally. */
4540 static void
4543 {
4545 }
4547 /* Push a member name on the stack. Printed as '.' STRING. */
4549 static void
4551 tree decl;
4553 {
4557 }
4559 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4561 static void
4564 {
4566 }
4568 /* Compute the maximum size in bytes of the printed spelling. */
4570 static int
4572 {
4577 {
4580 else
4582 }
4585 }
4587 /* Print the spelling to BUFFER and return it. */
4592 {
4598 {
4601 }
4602 else
4603 {
4608 ;
4609 }
4612 }
4614 /* Issue an error message for a bad initializer component.
4615 MSGID identifies the message.
4616 The component name is taken from the spelling stack. */
4618 void
4621 {
4628 }
4630 /* Issue a pedantic warning for a bad initializer component.
4631 MSGID identifies the message.
4632 The component name is taken from the spelling stack. */
4634 void
4637 {
4644 }
4646 /* Issue a warning for a bad initializer component.
4647 MSGID identifies the message.
4648 The component name is taken from the spelling stack. */
4650 static void
4653 {
4660 }
4661 \f
4662 /* Digest the parser output INIT as an initializer for type TYPE.
4663 Return a C expression of type TYPE to represent the initial value.
4665 REQUIRE_CONSTANT requests an error if non-constant initializers or
4666 elements are seen. */
4668 static tree
4672 {
4681 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4682 /* Do not use STRIP_NOPS here. We do not want an enumerator
4683 whose value is 0 to count as a null pointer constant. */
4689 /* Initialization of an array of chars from a string constant
4690 optionally enclosed in braces. */
4693 {
4701 {
4709 {
4712 }
4716 {
4719 }
4725 /* Subtract 1 (or sizeof (wchar_t))
4726 because it's ok to ignore the terminating null char
4727 that is counted in the length of the constant. */
4738 }
4739 }
4741 /* Any type can be initialized
4742 from an expression of the same type, optionally with braces. */
4756 {
4762 {
4763 /* As an extension, allow initializing objects with static storage
4764 duration with compound literals (which are then treated just as
4765 the brace enclosed list they contain). */
4768 }
4772 {
4775 }
4780 /* Compound expressions can only occur here if -pedantic or
4781 -pedantic-errors is specified. In the later case, we always want
4782 an error. In the former case, we simply want a warning. */
4785 {
4786 inside_init
4791 else
4795 }
4798 /* This test catches things like `7 / 0' which
4799 result in an expression for which TREE_CONSTANT
4800 is true, but which is not actually something
4801 that is a legal constant. We really should not
4802 be using this function, because it is a part of
4803 the back-end. Instead, the expression should
4804 already have been turned into ERROR_MARK_NODE. */
4807 {
4810 }
4813 }
4815 /* Handle scalar types, including conversions. */
4819 {
4820 /* Note that convert_for_assignment calls default_conversion
4821 for arrays and functions. We must not call it in the
4822 case where inside_init is a null pointer constant. */
4823 inside_init
4828 {
4831 }
4834 {
4837 }
4840 }
4842 /* Come here only for records and arrays. */
4845 {
4848 }
4852 }
4853 \f
4854 /* Handle initializers that use braces. */
4856 /* Type of object we are accumulating a constructor for.
4857 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4860 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4861 left to fill. */
4864 /* For an ARRAY_TYPE, this is the specified index
4865 at which to store the next element we get. */
4868 /* For an ARRAY_TYPE, this is the maximum index. */
4871 /* For a RECORD_TYPE, this is the first field not yet written out. */
4874 /* For an ARRAY_TYPE, this is the index of the first element
4875 not yet written out. */
4878 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4879 This is so we can generate gaps between fields, when appropriate. */
4882 /* If we are saving up the elements rather than allocating them,
4883 this is the list of elements so far (in reverse order,
4884 most recent first). */
4887 /* 1 if constructor should be incrementally stored into a constructor chain,
4888 0 if all the elements should be kept in AVL tree. */
4891 /* 1 if so far this constructor's elements are all compile-time constants. */
4894 /* 1 if so far this constructor's elements are all valid address constants. */
4897 /* 1 if this constructor is erroneous so far. */
4900 /* 1 if have called defer_addressed_constants. */
4903 /* Structure for managing pending initializer elements, organized as an
4904 AVL tree. */
4906 struct init_node
4907 {
4911 tree purpose;
4912 tree value;
4913 };
4915 /* Tree of pending elements at this constructor level.
4916 These are elements encountered out of order
4917 which belong at places we haven't reached yet in actually
4918 writing the output.
4919 Will never hold tree nodes across GC runs. */
4922 /* The SPELLING_DEPTH of this constructor. */
4925 /* 0 if implicitly pushing constructor levels is allowed. */
4931 /* DECL node for which an initializer is being read.
4932 0 means we are reading a constructor expression
4933 such as (struct foo) {...}. */
4936 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4939 /* Nonzero if this is an initializer for a top-level decl. */
4942 /* Nonzero if there were any member designators in this initializer. */
4945 /* Nesting depth of designator list. */
4948 /* Nonzero if there were diagnosed errors in this designator list. */
4951 \f
4952 /* This stack has a level for each implicit or explicit level of
4953 structuring in the initializer, including the outermost one. It
4954 saves the values of most of the variables above. */
4958 struct constructor_stack
4959 {
4961 tree type;
4962 tree fields;
4963 tree index;
4964 tree max_index;
4965 tree unfilled_index;
4966 tree unfilled_fields;
4967 tree bit_index;
4968 tree elements;
4972 /* If nonzero, this value should replace the entire
4973 constructor at this level. */
4974 tree replacement_value;
4983 };
4987 /* This stack represents designators from some range designator up to
4988 the last designator in the list. */
4990 struct constructor_range_stack
4991 {
4994 tree range_start;
4995 tree index;
4996 tree range_end;
4997 tree fields;
4998 };
5002 /* This stack records separate initializers that are nested.
5003 Nested initializers can't happen in ANSI C, but GNU C allows them
5004 in cases like { ... (struct foo) { ... } ... }. */
5006 struct initializer_stack
5007 {
5009 tree decl;
5013 tree elements;
5021 };
5024 \f
5025 /* Prepare to parse and output the initializer for variable DECL. */
5027 void
5029 tree decl;
5030 tree asmspec_tree;
5032 {
5063 {
5065 require_constant_elements
5067 /* For a scalar, you can always use any value to initialize,
5068 even within braces. */
5074 }
5075 else
5076 {
5080 }
5093 }
5095 void
5097 {
5100 /* Output subconstants (string constants, usually)
5101 that were referenced within this initializer and saved up.
5102 Must do this if and only if we called defer_addressed_constants. */
5106 /* Free the whole constructor stack of this initializer. */
5108 {
5112 }
5117 /* Pop back to the data of the outer initializer (if any). */
5132 }
5133 \f
5134 /* Call here when we see the initializer is surrounded by braces.
5135 This is instead of a call to push_init_level;
5136 it is matched by a call to pop_init_level.
5138 TYPE is the type to initialize, for a constructor expression.
5139 For an initializer for a decl, TYPE is zero. */
5141 void
5143 tree type;
5144 {
5186 {
5188 /* Skip any nameless bit fields at the beginning. */
5195 }
5197 {
5199 {
5200 constructor_max_index
5203 /* Detect non-empty initializations of zero-length arrays. */
5208 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5209 to initialize VLAs will cause an proper error; avoid tree
5210 checking errors as well by setting a safe value. */
5215 constructor_index
5218 }
5219 else
5223 }
5225 {
5226 /* Vectors are like simple fixed-size arrays. */
5227 constructor_max_index =
5231 }
5232 else
5233 {
5234 /* Handle the case of int x = {5}; */
5237 }
5238 }
5239 \f
5240 /* Push down into a subobject, for initialization.
5241 If this is for an explicit set of braces, IMPLICIT is 0.
5242 If it is because the next element belongs at a lower level,
5243 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5245 void
5248 {
5252 /* If we've exhausted any levels that didn't have braces,
5253 pop them now. */
5255 {
5263 else
5265 }
5267 /* Unless this is an explicit brace, we need to preserve previous
5268 content if any. */
5270 {
5277 }
5310 {
5315 }
5317 /* Don't die if an entire brace-pair level is superfluous
5318 in the containing level. */
5320 ;
5323 {
5324 /* Don't die if there are extra init elts at the end. */
5327 else
5328 {
5331 constructor_depth++;
5332 }
5333 }
5335 {
5338 constructor_depth++;
5339 }
5342 {
5347 }
5350 {
5358 }
5361 {
5364 }
5368 {
5370 /* Skip any nameless bit fields at the beginning. */
5377 }
5379 {
5380 /* Vectors are like simple fixed-size arrays. */
5381 constructor_max_index =
5385 }
5387 {
5389 {
5390 constructor_max_index
5393 /* Detect non-empty initializations of zero-length arrays. */
5398 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5399 to initialize VLAs will cause an proper error; avoid tree
5400 checking errors as well by setting a safe value. */
5405 constructor_index
5408 }
5409 else
5414 {
5415 /* We need to split the char/wchar array into individual
5416 characters, so that we don't have to special case it
5417 everywhere. */
5419 }
5420 }
5421 else
5422 {
5426 }
5427 }
5429 /* At the end of an implicit or explicit brace level,
5430 finish up that level of constructor.
5431 If we were outputting the elements as they are read, return 0
5432 from inner levels (process_init_element ignores that),
5433 but return error_mark_node from the outermost level
5434 (that's what we want to put in DECL_INITIAL).
5435 Otherwise, return a CONSTRUCTOR expression. */
5437 tree
5440 {
5445 {
5446 /* When we come to an explicit close brace,
5447 pop any inner levels that didn't have explicit braces. */
5453 }
5457 /* Error for initializing a flexible array member, or a zero-length
5458 array member in an inappropriate context. */
5463 {
5464 /* Silently discard empty initializations. The parser will
5465 already have pedwarned for empty brackets. */
5469 {
5475 /* We have already issued an error message for the existence
5476 of a flexible array member not at the end of the structure.
5477 Discard the initializer so that we do not abort later. */
5480 }
5481 else
5482 /* Zero-length arrays are no longer special, so we should no longer
5483 get here. */
5485 }
5487 /* Warn when some struct elements are implicitly initialized to zero. */
5489 && constructor_type
5492 {
5493 /* Do not warn for flexible array members or zero-length arrays. */
5499 /* Do not warn if this level of the initializer uses member
5500 designators; it is likely to be deliberate. */
5502 {
5506 }
5507 }
5509 /* Now output all pending elements. */
5513 /* Pad out the end of the structure. */
5515 /* If this closes a superfluous brace pair,
5516 just pass out the element between them. */
5519 ;
5524 {
5525 /* A nonincremental scalar initializer--just return
5526 the element, after verifying there is just one. */
5528 {
5532 }
5534 {
5537 }
5538 else
5540 }
5541 else
5542 {
5545 else
5546 {
5553 }
5554 }
5579 {
5583 }
5585 }
5587 /* Common handling for both array range and field name designators.
5588 ARRAY argument is non-zero for array ranges. Returns zero for success. */
5590 static int
5593 {
5594 tree subtype;
5597 /* Don't die if an entire brace-pair level is superfluous
5598 in the containing level. */
5602 /* If there were errors in this designator list already, bail out silently. */
5607 {
5611 /* Designator list starts at the level of closest explicit
5612 braces. */
5617 }
5620 {
5623 }
5627 {
5631 }
5633 {
5635 }
5636 else
5641 {
5644 }
5646 {
5649 }
5654 }
5656 /* If there are range designators in designator list, push a new designator
5657 to constructor_range_stack. RANGE_END is end of such stack range or
5658 NULL_TREE if there is no range designator at this level. */
5660 static void
5662 tree range_end;
5663 {
5678 }
5680 /* Within an array initializer, specify the next index to be initialized.
5681 FIRST is that index. If LAST is nonzero, then initialize a range
5682 of indices, running from FIRST through LAST. */
5684 void
5687 {
5717 else
5718 {
5722 {
5726 {
5729 }
5730 else
5731 {
5735 {
5738 }
5739 }
5740 }
5742 designator_depth++;
5746 }
5747 }
5749 /* Within a struct initializer, specify the next field to be initialized. */
5751 void
5753 tree fieldname;
5754 {
5755 tree tail;
5764 {
5767 }
5771 {
5774 }
5779 else
5780 {
5782 designator_depth++;
5786 }
5787 }
5788 \f
5789 /* Add a new initializer to the tree of pending initializers. PURPOSE
5790 identifies the initializer, either array index or field in a structure.
5791 VALUE is the value of that index or field. */
5793 static void
5796 {
5803 {
5805 {
5811 else
5812 {
5817 }
5818 }
5819 }
5820 else
5821 {
5822 tree bitpos;
5826 {
5832 else
5833 {
5838 }
5839 }
5840 }
5853 {
5857 {
5861 {
5863 {
5864 /* L rotation. */
5877 {
5880 else
5882 }
5883 else
5885 }
5886 else
5887 {
5888 /* LR rotation. */
5910 {
5913 else
5915 }
5916 else
5918 }
5920 }
5921 else
5922 {
5923 /* p->balance == +1; growth of left side balances the node. */
5926 }
5927 }
5929 {
5931 /* Growth propagation from right side. */
5934 {
5936 {
5937 /* R rotation. */
5950 {
5953 else
5955 }
5956 else
5958 }
5960 {
5961 /* RL rotation */
5983 {
5986 else
5988 }
5989 else
5991 }
5993 }
5994 else
5995 {
5996 /* p->balance == -1; growth of right side balances the node. */
5999 }
6000 }
6004 }
6005 }
6007 /* Build AVL tree from a sorted chain. */
6009 static void
6011 {
6012 tree chain;
6022 {
6024 /* Skip any nameless bit fields at the beginning. */
6030 }
6032 {
6034 constructor_unfilled_index
6037 else
6039 }
6041 }
6043 /* Build AVL tree from a string constant. */
6045 static void
6047 tree str;
6048 {
6063 else
6074 {
6076 {
6079 }
6080 else
6081 {
6085 {
6088 else
6093 }
6094 }
6097 {
6100 {
6102 {
6105 }
6106 }
6108 {
6111 }
6116 }
6121 }
6124 }
6126 /* Return value of FIELD in pending initializer or zero if the field was
6127 not initialized yet. */
6129 static tree
6131 tree field;
6132 {
6136 {
6143 {
6148 else
6150 }
6151 }
6153 {
6157 && (!constructor_unfilled_fields
6164 {
6169 else
6171 }
6172 }
6174 {
6178 }
6180 }
6182 /* "Output" the next constructor element.
6183 At top level, really output it to assembler code now.
6184 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6185 TYPE is the data type that the containing data type wants here.
6186 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6188 PENDING if non-nil means output pending elements that belong
6189 right after this element. (PENDING is normally 1;
6190 it is 0 while outputting pending elements, to avoid recursion.) */
6192 static void
6196 {
6208 {
6209 /* As an extension, allow initializing objects with static storage
6210 duration with compound literals (which are then treated just as
6211 the brace enclosed list they contain). */
6214 }
6228 {
6231 }
6236 /* If this field is empty (and not at the end of structure),
6237 don't do anything other than checking the initializer. */
6248 {
6251 }
6253 /* If this element doesn't come next in sequence,
6254 put it on constructor_pending_elts. */
6256 && (!constructor_incremental
6258 {
6265 }
6267 && (!constructor_incremental
6269 {
6270 /* We do this for records but not for unions. In a union,
6271 no matter which field is specified, it can be initialized
6272 right away since it starts at the beginning of the union. */
6274 {
6277 else
6278 {
6286 }
6287 }
6291 }
6294 {
6298 /* We can have just one union field set. */
6300 }
6302 /* Otherwise, output this element either to
6303 constructor_elements or to the assembler file. */
6307 constructor_elements
6310 /* Advance the variable that indicates sequential elements output. */
6312 constructor_unfilled_index
6314 bitsize_one_node);
6316 {
6317 constructor_unfilled_fields
6320 /* Skip any nameless bit fields. */
6324 constructor_unfilled_fields =
6326 }
6330 /* Now output any pending elements which have become next. */
6333 }
6335 /* Output any pending elements which have become next.
6336 As we output elements, constructor_unfilled_{fields,index}
6337 advances, which may cause other elements to become next;
6338 if so, they too are output.
6340 If ALL is 0, we return when there are
6341 no more pending elements to output now.
6343 If ALL is 1, we output space as necessary so that
6344 we can output all the pending elements. */
6346 static void
6349 {
6351 tree next;
6353 retry:
6355 /* Look thru the whole pending tree.
6356 If we find an element that should be output now,
6357 output it. Otherwise, set NEXT to the element
6358 that comes first among those still pending. */
6362 {
6364 {
6366 constructor_unfilled_index))
6372 {
6373 /* Advance to the next smaller node. */
6376 else
6377 {
6378 /* We have reached the smallest node bigger than the
6379 current unfilled index. Fill the space first. */
6382 }
6383 }
6384 else
6385 {
6386 /* Advance to the next bigger node. */
6389 else
6390 {
6391 /* We have reached the biggest node in a subtree. Find
6392 the parent of it, which is the next bigger node. */
6398 {
6401 }
6402 }
6403 }
6404 }
6407 {
6410 /* If the current record is complete we are done. */
6416 /* We can't compare fields here because there might be empty
6417 fields in between. */
6419 {
6423 }
6425 {
6426 /* Advance to the next smaller node. */
6429 else
6430 {
6431 /* We have reached the smallest node bigger than the
6432 current unfilled field. Fill the space first. */
6435 }
6436 }
6437 else
6438 {
6439 /* Advance to the next bigger node. */
6442 else
6443 {
6444 /* We have reached the biggest node in a subtree. Find
6445 the parent of it, which is the next bigger node. */
6452 {
6455 }
6456 }
6457 }
6458 }
6459 }
6461 /* Ordinarily return, but not if we want to output all
6462 and there are elements left. */
6466 /* If it's not incremental, just skip over the gap, so that after
6467 jumping to retry we will output the next successive element. */
6474 /* ELT now points to the node in the pending tree with the next
6475 initializer to output. */
6477 }
6478 \f
6479 /* Add one non-braced element to the current constructor level.
6480 This adjusts the current position within the constructor's type.
6481 This may also start or terminate implicit levels
6482 to handle a partly-braced initializer.
6484 Once this has found the correct level for the new element,
6485 it calls output_init_element. */
6487 void
6489 tree value;
6490 {
6497 /* Handle superfluous braces around string cst as in
6498 char x[] = {"foo"}; */
6500 && constructor_type
6504 {
6509 }
6512 {
6515 }
6517 /* Ignore elements of a brace group if it is entirely superfluous
6518 and has already been diagnosed. */
6522 /* If we've exhausted any levels that didn't have braces,
6523 pop them now. */
6525 {
6533 constructor_index)))
6535 else
6537 }
6539 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6541 {
6542 /* If value is a compound literal and we'll be just using its
6543 content, don't put it into a SAVE_EXPR. */
6545 || !require_constant_value
6548 }
6551 {
6553 {
6554 tree fieldtype;
6558 {
6561 }
6568 /* Error for non-static initialization of a flexible array member. */
6570 && !require_constant_value
6573 {
6576 }
6578 /* Accept a string constant to initialize a subarray. */
6584 /* Otherwise, if we have come to a subaggregate,
6585 and we don't have an element of its type, push into it. */
6591 {
6594 }
6597 {
6601 }
6602 else
6603 /* Do the bookkeeping for an element that was
6604 directly output as a constructor. */
6605 {
6606 /* For a record, keep track of end position of last field. */
6608 constructor_bit_index
6614 /* Skip any nameless bit fields. */
6618 constructor_unfilled_fields =
6620 }
6623 /* Skip any nameless bit fields at the beginning. */
6628 }
6630 {
6631 tree fieldtype;
6635 {
6638 }
6645 /* Warn that traditional C rejects initialization of unions.
6646 We skip the warning if the value is zero. This is done
6647 under the assumption that the zero initializer in user
6648 code appears conditioned on e.g. __STDC__ to avoid
6649 "missing initializer" warnings and relies on default
6650 initialization to zero in the traditional C case.
6651 We also skip the warning if the initializer is designated,
6652 again on the assumption that this must be conditional on
6653 __STDC__ anyway (and we've already complained about the
6654 member-designator already). */
6659 /* Accept a string constant to initialize a subarray. */
6665 /* Otherwise, if we have come to a subaggregate,
6666 and we don't have an element of its type, push into it. */
6672 {
6675 }
6678 {
6682 }
6683 else
6684 /* Do the bookkeeping for an element that was
6685 directly output as a constructor. */
6686 {
6689 }
6692 }
6694 {
6698 /* Accept a string constant to initialize a subarray. */
6704 /* Otherwise, if we have come to a subaggregate,
6705 and we don't have an element of its type, push into it. */
6711 {
6714 }
6719 {
6722 }
6724 /* Now output the actual element. */
6726 {
6730 }
6732 constructor_index
6736 /* If we are doing the bookkeeping for an element that was
6737 directly output as a constructor, we must update
6738 constructor_unfilled_index. */
6740 }
6742 {
6745 /* Do a basic check of initializer size. Note that vectors
6746 always have a fixed size derived from their type. */
6748 {
6751 }
6753 /* Now output the actual element. */
6757 constructor_index
6761 /* If we are doing the bookkeeping for an element that was
6762 directly output as a constructor, we must update
6763 constructor_unfilled_index. */
6765 }
6767 /* Handle the sole element allowed in a braced initializer
6768 for a scalar variable. */
6770 {
6773 }
6774 else
6775 {
6779 }
6781 /* Handle range initializers either at this level or anywhere higher
6782 in the designator stack. */
6784 {
6791 {
6795 }
6799 {
6803 }
6810 {
6814 {
6817 }
6825 }
6830 }
6833 }
6836 }
6837 \f
6838 /* Build a simple asm-statement, from one string literal. */
6839 tree
6841 tree expr;
6842 {
6849 {
6850 tree stmt;
6854 NULL_TREE));
6857 }
6861 }
6863 /* Build an asm-statement, whose components are a CV_QUALIFIER, a
6864 STRING, some OUTPUTS, some INPUTS, and some CLOBBERS. */
6866 tree
6868 tree cv_qualifier;
6869 tree string;
6870 tree outputs;
6871 tree inputs;
6872 tree clobbers;
6873 {
6874 tree tail;
6877 {
6880 }
6884 {
6888 }
6890 /* We can remove output conversions that change the type,
6891 but not the mode. */
6893 {
6899 /* Allow conversions as LHS here. build_modify_expr as called below
6900 will do the right thing with them. */
6911 }
6913 /* Remove output conversions that change the type but not the mode. */
6915 {
6919 }
6921 /* Perform default conversions on array and function inputs.
6922 Don't do this for other types as it would screw up operands
6923 expected to be in memory. */
6929 }
6931 /* Expand an ASM statement with operands, handling output operands
6932 that are not variables or INDIRECT_REFS by transforming such
6933 cases into cases that expand_asm_operands can handle.
6935 Arguments are same as for expand_asm_operands. */
6937 void
6943 {
6946 /* o[I] is the place that output number I should be written. */
6948 tree tail;
6950 /* Record the contents of OUTPUTS before it is modified. */
6954 /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of
6955 OUTPUTS some trees for where the values were actually stored. */
6958 /* Copy all the intermediate outputs into the specified outputs. */
6960 {
6962 {
6967 /* Restore the original value so that it's correct the next
6968 time we expand this function. */
6970 }
6971 /* Detect modification of read-only values.
6972 (Otherwise done by build_modify_expr.) */
6973 else
6974 {
6982 }
6983 }
6985 /* Those MODIFY_EXPRs could do autoincrements. */
6987 }
6988 \f
6989 /* Expand a C `return' statement.
6990 RETVAL is the expression for what to return,
6991 or a null pointer for `return;' with no value. */
6993 tree
6995 tree retval;
6996 {
7003 {
7008 }
7010 {
7014 }
7015 else
7016 {
7020 tree inner;
7028 /* Strip any conversions, additions, and subtractions, and see if
7029 we are returning the address of a local variable. Warn if so. */
7031 {
7033 {
7040 /* If the second operand of the MINUS_EXPR has a pointer
7041 type (or is converted from it), this may be valid, so
7042 don't give a warning. */
7043 {
7057 }
7074 }
7077 }
7080 }
7083 }
7084 \f
7086 /* The SWITCH_STMT being built. */
7087 tree switch_stmt;
7088 /* A splay-tree mapping the low element of a case range to the high
7089 element, or NULL_TREE if there is no high element. Used to
7090 determine whether or not a new case label duplicates an old case
7091 label. We need a tree, rather than simply a hash table, because
7092 of the GNU case range extension. */
7093 splay_tree cases;
7094 /* The next node on the stack. */
7096 };
7098 /* A stack of the currently active switch statements. The innermost
7099 switch statement is on the top of the stack. There is no need to
7100 mark the stack for garbage collection because it is only active
7101 during the processing of the body of a function, and we never
7102 collect at that point. */
7106 /* Start a C switch statement, testing expression EXP. Return the new
7107 SWITCH_STMT. */
7109 tree
7111 tree exp;
7112 {
7118 {
7124 {
7127 }
7128 else
7129 {
7139 }
7140 }
7142 /* Add this new SWITCH_STMT to the stack. */
7150 }
7152 /* Process a case label. */
7154 tree
7156 tree low_value;
7157 tree high_value;
7158 {
7162 {
7168 }
7171 else
7175 }
7177 /* Finish the switch statement. */
7179 void
7181 {
7186 /* Pop the stack. */
7190 }