| blob | 7e91d4fc69217d604f346c8ca8b680c952676b2d |
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 for errors in format strings. */
1584 /* Recognize certain built-in functions so we can make tree-codes
1585 other than CALL_EXPR. We do this when it enables fold-const.c
1586 to do something useful. */
1591 {
1596 }
1606 }
1607 \f
1608 /* Convert the argument expressions in the list VALUES
1609 to the types in the list TYPELIST. The result is a list of converted
1610 argument expressions.
1612 If TYPELIST is exhausted, or when an element has NULL as its type,
1613 perform the default conversions.
1615 PARMLIST is the chain of parm decls for the function being called.
1616 It may be 0, if that info is not available.
1617 It is used only for generating error messages.
1619 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1621 This is also where warnings about wrong number of args are generated.
1623 Both VALUES and the returned value are chains of TREE_LIST nodes
1624 with the elements of the list in the TREE_VALUE slots of those nodes. */
1626 static tree
1629 {
1634 /* Scan the given expressions and types, producing individual
1635 converted arguments and pushing them on RESULT in reverse order. */
1638 valtail;
1640 {
1645 {
1649 else
1652 }
1654 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1655 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1656 to convert automatically to a pointer. */
1665 {
1666 /* Formal parm type is specified by a function prototype. */
1667 tree parmval;
1670 {
1673 }
1674 else
1675 {
1676 /* Optionally warn about conversions that
1677 differ from the default conversions. */
1679 {
1684 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1687 warn_for_assignment ("%s as integer rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1690 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1693 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1696 warn_for_assignment ("%s as complex rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1699 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1700 /* ??? At some point, messages should be written about
1701 conversions between complex types, but that's too messy
1702 to do now. */
1705 {
1706 /* Warn if any argument is passed as `float',
1707 since without a prototype it would be `double'. */
1709 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1710 }
1711 /* Detect integer changing in width or signedness.
1712 These warnings are only activated with
1713 -Wconversion, not with -Wtraditional. */
1716 {
1723 /* No warning if function asks for enum
1724 and the actual arg is that enum type. */
1725 ;
1727 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1729 ;
1730 /* Don't complain if the formal parameter type
1731 is an enum, because we can't tell now whether
1732 the value was an enum--even the same enum. */
1734 ;
1737 /* Change in signedness doesn't matter
1738 if a constant value is unaffected. */
1739 ;
1740 /* Likewise for a constant in a NOP_EXPR. */
1744 ;
1749 /* Change in signedness doesn't matter
1750 if an enum value is unaffected. */
1751 ;
1752 #endif
1753 /* If the value is extended from a narrower
1754 unsigned type, it doesn't matter whether we
1755 pass it as signed or unsigned; the value
1756 certainly is the same either way. */
1759 ;
1762 else
1764 }
1765 }
1775 }
1777 }
1781 /* Convert `float' to `double'. */
1783 else
1784 /* Convert `short' and `char' to full-size `int'. */
1789 }
1792 {
1796 else
1798 }
1801 }
1802 \f
1803 /* This is the entry point used by the parser
1804 for binary operators in the input.
1805 In addition to constructing the expression,
1806 we check for operands that were written with other binary operators
1807 in a way that is likely to confuse the user. */
1809 tree
1813 {
1830 /* Check for cases such as x+y<<z which users are likely
1831 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1832 is cleared to prevent these warnings. */
1834 {
1836 {
1840 }
1843 {
1847 }
1850 {
1856 /* Check cases like x|y==z */
1859 }
1862 {
1868 /* Check cases like x^y==z */
1871 }
1874 {
1878 /* Check cases like x&y==z */
1881 }
1882 }
1884 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1895 /* Record the code that was specified in the source,
1896 for the sake of warnings about confusing nesting. */
1899 else
1900 {
1902 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1903 so that convert_for_assignment wouldn't strip it.
1904 That way, we got warnings for things like p = (1 - 1).
1905 But it turns out we should not get those warnings. */
1909 }
1912 }
1914 /* Build a binary-operation expression without default conversions.
1915 CODE is the kind of expression to build.
1916 This function differs from `build' in several ways:
1917 the data type of the result is computed and recorded in it,
1918 warnings are generated if arg data types are invalid,
1919 special handling for addition and subtraction of pointers is known,
1920 and some optimization is done (operations on narrow ints
1921 are done in the narrower type when that gives the same result).
1922 Constant folding is also done before the result is returned.
1924 Note that the operands will never have enumeral types, or function
1925 or array types, because either they will have the default conversions
1926 performed or they have both just been converted to some other type in which
1927 the arithmetic is to be done. */
1929 tree
1934 {
1939 /* Expression code to give to the expression when it is built.
1940 Normally this is CODE, which is what the caller asked for,
1941 but in some special cases we change it. */
1944 /* Data type in which the computation is to be performed.
1945 In the simplest cases this is the common type of the arguments. */
1948 /* Nonzero means operands have already been type-converted
1949 in whatever way is necessary.
1950 Zero means they need to be converted to RESULT_TYPE. */
1953 /* Nonzero means create the expression with this type, rather than
1954 RESULT_TYPE. */
1957 /* Nonzero means after finally constructing the expression
1958 convert it to this type. */
1961 /* Nonzero if this is an operation like MIN or MAX which can
1962 safely be computed in short if both args are promoted shorts.
1963 Also implies COMMON.
1964 -1 indicates a bitwise operation; this makes a difference
1965 in the exact conditions for when it is safe to do the operation
1966 in a narrower mode. */
1969 /* Nonzero if this is a comparison operation;
1970 if both args are promoted shorts, compare the original shorts.
1971 Also implies COMMON. */
1974 /* Nonzero if this is a right-shift operation, which can be computed on the
1975 original short and then promoted if the operand is a promoted short. */
1978 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1982 {
1985 }
1986 else
1987 {
1990 }
1995 /* The expression codes of the data types of the arguments tell us
1996 whether the arguments are integers, floating, pointers, etc. */
2000 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2004 /* If an error was already reported for one of the arguments,
2005 avoid reporting another error. */
2011 {
2013 /* Handle the pointer + int case. */
2018 else
2023 /* Subtraction of two similar pointers.
2024 We must subtract them as integers, then divide by object size. */
2028 /* Handle pointer minus int. Just like pointer plus int. */
2031 else
2044 /* Floating point division by zero is a legitimate way to obtain
2045 infinities and NaNs. */
2053 {
2056 else
2057 /* Although it would be tempting to shorten always here, that
2058 loses on some targets, since the modulo instruction is
2059 undefined if the quotient can't be represented in the
2060 computation mode. We shorten only if unsigned or if
2061 dividing by something we know != -1. */
2066 }
2083 {
2084 /* Although it would be tempting to shorten always here, that loses
2085 on some targets, since the modulo instruction is undefined if the
2086 quotient can't be represented in the computation mode. We shorten
2087 only if unsigned or if dividing by something we know != -1. */
2092 }
2104 {
2105 /* Result of these operations is always an int,
2106 but that does not mean the operands should be
2107 converted to ints! */
2112 }
2115 /* Shift operations: result has same type as first operand;
2116 always convert second operand to int.
2117 Also set SHORT_SHIFT if shifting rightward. */
2121 {
2123 {
2126 else
2127 {
2133 }
2134 }
2136 /* Use the type of the value to be shifted. */
2138 /* Convert the shift-count to an integer, regardless of size
2139 of value being shifted. */
2142 /* Avoid converting op1 to result_type later. */
2144 }
2149 {
2151 {
2157 }
2159 /* Use the type of the value to be shifted. */
2161 /* Convert the shift-count to an integer, regardless of size
2162 of value being shifted. */
2165 /* Avoid converting op1 to result_type later. */
2167 }
2173 {
2175 {
2180 }
2182 /* Use the type of the value to be shifted. */
2184 /* Convert the shift-count to an integer, regardless of size
2185 of value being shifted. */
2188 /* Avoid converting op1 to result_type later. */
2190 }
2197 /* Result of comparison is always int,
2198 but don't convert the args to int! */
2206 {
2209 /* Anything compares with void *. void * compares with anything.
2210 Otherwise, the targets must be compatible
2211 and both must be object or both incomplete. */
2215 {
2216 /* op0 != orig_op0 detects the case of something
2217 whose value is 0 but which isn't a valid null ptr const. */
2221 }
2223 {
2227 }
2228 else
2233 }
2241 {
2244 }
2246 {
2249 }
2258 {
2260 {
2265 }
2266 else
2267 {
2270 }
2271 }
2283 {
2285 {
2293 }
2294 else
2295 {
2298 }
2299 }
2302 {
2306 }
2309 {
2313 }
2315 {
2318 }
2320 {
2323 }
2335 {
2338 }
2344 }
2347 &&
2349 {
2355 /* For certain operations (which identify themselves by shorten != 0)
2356 if both args were extended from the same smaller type,
2357 do the arithmetic in that type and then extend.
2359 shorten !=0 and !=1 indicates a bitwise operation.
2360 For them, this optimization is safe only if
2361 both args are zero-extended or both are sign-extended.
2362 Otherwise, we might change the result.
2363 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2364 but calculated in (unsigned short) it would be (unsigned short)-1. */
2367 {
2371 /* UNS is 1 if the operation to be done is an unsigned one. */
2373 tree type;
2377 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2378 but it *requires* conversion to FINAL_TYPE. */
2389 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2391 /* For bitwise operations, signedness of nominal type
2392 does not matter. Consider only how operands were extended. */
2396 /* Note that in all three cases below we refrain from optimizing
2397 an unsigned operation on sign-extended args.
2398 That would not be valid. */
2400 /* Both args variable: if both extended in same way
2401 from same width, do it in that width.
2402 Do it unsigned if args were zero-extended. */
2409 result_type
2410 = c_common_signed_or_unsigned_type
2416 && (type
2425 && (type
2430 }
2432 /* Shifts can be shortened if shifting right. */
2435 {
2445 /* We can shorten only if the shift count is less than the
2446 number of bits in the smaller type size. */
2448 /* We cannot drop an unsigned shift after sign-extension. */
2450 {
2451 /* Do an unsigned shift if the operand was zero-extended. */
2452 result_type
2455 /* Convert value-to-be-shifted to that type. */
2459 }
2460 }
2462 /* Comparison operations are shortened too but differently.
2463 They identify themselves by setting short_compare = 1. */
2466 {
2467 /* Don't write &op0, etc., because that would prevent op0
2468 from being kept in a register.
2469 Instead, make copies of the our local variables and
2470 pass the copies by reference, then copy them back afterward. */
2473 tree val
2485 {
2497 /* Give warnings for comparisons between signed and unsigned
2498 quantities that may fail.
2500 Do the checking based on the original operand trees, so that
2501 casts will be considered, but default promotions won't be.
2503 Do not warn if the comparison is being done in a signed type,
2504 since the signed type will only be chosen if it can represent
2505 all the values of the unsigned type. */
2508 /* Do not warn if both operands are the same signedness. */
2511 else
2512 {
2517 else
2520 /* Do not warn if the signed quantity is an
2521 unsuffixed integer literal (or some static
2522 constant expression involving such literals or a
2523 conditional expression involving such literals)
2524 and it is non-negative. */
2527 /* Do not warn if the comparison is an equality operation,
2528 the unsigned quantity is an integral constant, and it
2529 would fit in the result if the result were signed. */
2532 && int_fits_type_p
2535 /* Do not warn if the unsigned quantity is an enumeration
2536 constant and its maximum value would fit in the result
2537 if the result were signed. */
2540 && int_fits_type_p
2544 else
2546 }
2548 /* Warn if two unsigned values are being compared in a size
2549 larger than their original size, and one (and only one) is the
2550 result of a `~' operator. This comparison will always fail.
2552 Also warn if one operand is a constant, and the constant
2553 does not have all bits set that are set in the ~ operand
2554 when it is extended. */
2558 {
2562 else
2567 {
2568 tree primop;
2573 {
2577 }
2578 else
2579 {
2583 }
2588 {
2592 }
2593 }
2600 }
2601 }
2602 }
2603 }
2605 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2606 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2607 Then the expression will be built.
2608 It will be given type FINAL_TYPE if that is nonzero;
2609 otherwise, it will be given type RESULT_TYPE. */
2612 {
2615 }
2618 {
2623 }
2628 {
2630 tree folded;
2638 }
2639 }
2640 \f
2641 /* Return a tree for the difference of pointers OP0 and OP1.
2642 The resulting tree has type int. */
2644 static tree
2647 {
2656 {
2661 }
2663 /* If the conversion to ptrdiff_type does anything like widening or
2664 converting a partial to an integral mode, we get a convert_expression
2665 that is in the way to do any simplifications.
2666 (fold-const.c doesn't know that the extra bits won't be needed.
2667 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2668 different mode in place.)
2669 So first try to find a common term here 'by hand'; we want to cover
2670 at least the cases that occur in legal static initializers. */
2675 {
2678 }
2679 else
2683 {
2686 }
2687 else
2691 {
2694 }
2697 /* First do the subtraction as integers;
2698 then drop through to build the divide operator.
2699 Do not do default conversions on the minus operator
2700 in case restype is a short type. */
2704 /* This generates an error if op1 is pointer to incomplete type. */
2708 /* This generates an error if op0 is pointer to incomplete type. */
2711 /* Divide by the size, in easiest possible way. */
2719 }
2720 \f
2721 /* Construct and perhaps optimize a tree representation
2722 for a unary operation. CODE, a tree_code, specifies the operation
2723 and XARG is the operand.
2724 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2725 the default promotions (such as from short to int).
2726 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2727 allows non-lvalues; this is only used to handle conversion of non-lvalue
2728 arrays to pointers in C99. */
2730 tree
2733 tree xarg;
2735 {
2736 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2740 tree val;
2749 {
2751 /* This is used for unary plus, because a CONVERT_EXPR
2752 is enough to prevent anybody from looking inside for
2753 associativity, but won't generate any code. */
2756 {
2759 }
2768 {
2771 }
2778 {
2784 }
2786 {
2789 }
2797 {
2800 }
2806 /* Conjugating a real value is a no-op, but allow it anyway. */
2809 {
2812 }
2821 /* These will convert to a pointer. */
2823 {
2826 }
2838 else
2846 else
2853 /* Handle complex lvalues (when permitted)
2854 by reduction to simpler cases. */
2860 /* Increment or decrement the real part of the value,
2861 and don't change the imaginary part. */
2863 {
2874 }
2876 /* Report invalid types. */
2880 {
2883 else
2887 }
2889 {
2890 tree inc;
2896 /* Compute the increment. */
2899 {
2900 /* If pointer target is an undefined struct,
2901 we just cannot know how to do the arithmetic. */
2903 {
2906 else
2908 }
2912 {
2915 else
2917 }
2920 }
2921 else
2926 /* Handle incrementing a cast-expression. */
2930 {
2939 /* If the real type has the same machine representation
2940 as the type it is cast to, we can make better output
2941 by adding directly to the inside of the cast. */
2947 else
2948 {
2952 else
2953 {
2957 else
2966 }
2969 }
2974 }
2975 give_up:
2977 /* Complain about anything else that is not a true lvalue. */
2984 /* Report a read-only lvalue. */
2993 else
3000 }
3003 /* Note that this operation never does default_conversion. */
3005 /* Let &* cancel out to simplify resulting code. */
3007 {
3008 /* Don't let this be an lvalue. */
3012 }
3014 /* For &x[y], return x+y */
3016 {
3021 }
3023 /* Handle complex lvalues (when permitted)
3024 by reduction to simpler cases. */
3030 float f; *&(int)f = 3.4 stores in int format
3031 whereas (int)f = 3.4 stores in float format. */
3032 /* Address of a cast is just a cast of the address
3033 of the operand of the cast. */
3035 {
3048 }
3049 #endif
3051 /* Anything not already handled and not a true memory reference
3052 or a non-lvalue array is an error. */
3057 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3060 /* If the lvalue is const or volatile, merge that into the type
3061 to which the address will point. Note that you can't get a
3062 restricted pointer by taking the address of something, so we
3063 only have to deal with `const' and `volatile' here. */
3075 {
3076 tree addr;
3079 {
3085 {
3089 }
3094 }
3095 else
3098 /* Address of a static or external variable or
3099 file-scope function counts as a constant. */
3105 }
3109 }
3114 }
3116 #if 0
3117 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3118 convert ARG with the same conversions in the same order
3119 and return the result. */
3121 static tree
3123 tree conversions;
3124 tree arg;
3125 {
3127 {
3137 arg));
3141 }
3142 }
3145 /* Return nonzero if REF is an lvalue valid for this language.
3146 Lvalues can be assigned, unless their type has TYPE_READONLY.
3147 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3149 int
3151 tree ref;
3152 {
3156 {
3181 }
3182 }
3184 /* Return nonzero if REF is an lvalue valid for this language;
3185 otherwise, print an error message and return zero. */
3187 int
3189 tree ref;
3191 {
3198 }
3200 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3201 for certain kinds of expressions which are not really lvalues
3202 but which we can accept as lvalues. If FLAG is nonzero, then
3203 non-lvalues are OK since we may be converting a non-lvalue array to
3204 a pointer in C99.
3206 If ARG is not a kind of expression we can handle, return zero. */
3208 static tree
3211 tree arg;
3213 {
3214 /* Handle (a, b) used as an "lvalue". */
3216 {
3219 /* If this returns a function type, it isn't really being used as
3220 an lvalue, so don't issue a warning about it. */
3226 }
3228 /* Handle (a ? b : c) used as an "lvalue". */
3230 {
3240 }
3243 }
3245 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3246 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3248 static void
3251 {
3254 {
3264 }
3265 }
3266 \f
3267 /* Warn about storing in something that is `const'. */
3269 void
3271 tree arg;
3273 {
3275 {
3278 else
3281 }
3285 else
3287 }
3288 \f
3289 /* Mark EXP saying that we need to be able to take the
3290 address of it; it should not be allocated in a register.
3291 Returns true if successful. */
3293 bool
3295 tree exp;
3296 {
3301 {
3304 {
3308 }
3310 /* ... fall through ... */
3330 {
3332 {
3336 }
3339 }
3341 {
3343 {
3347 }
3349 /* If we are making this addressable due to its having
3350 volatile components, give a different error message. Also
3351 handle the case of an unnamed parameter by not trying
3352 to give the name. */
3355 {
3358 }
3362 }
3365 /* drops in */
3371 #endif
3375 }
3376 }
3377 \f
3378 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3380 tree
3383 {
3384 tree type1;
3385 tree type2;
3394 /* Don't promote the operands separately if they promote
3395 the same way. Return the unpromoted type and let the combined
3396 value get promoted if necessary. */
3402 {
3407 }
3408 #endif
3410 /* Promote both alternatives. */
3427 /* Quickly detect the usual case where op1 and op2 have the same type
3428 after promotion. */
3430 {
3433 else
3435 }
3440 {
3443 /* If -Wsign-compare, warn here if type1 and type2 have
3444 different signedness. We'll promote the signed to unsigned
3445 and later code won't know it used to be different.
3446 Do this check on the original types, so that explicit casts
3447 will be considered, but default promotions won't. */
3450 {
3455 {
3456 /* Do not warn if the result type is signed, since the
3457 signed type will only be chosen if it can represent
3458 all the values of the unsigned type. */
3461 /* Do not warn if the signed quantity is an unsuffixed
3462 integer literal (or some static constant expression
3463 involving such literals) and it is non-negative. */
3467 else
3469 }
3470 }
3471 }
3473 {
3477 }
3479 {
3489 {
3494 }
3496 {
3501 }
3502 else
3503 {
3506 }
3507 }
3509 {
3512 else
3513 {
3515 }
3517 }
3519 {
3522 else
3523 {
3525 }
3527 }
3530 {
3533 else
3534 {
3537 }
3538 }
3540 /* Merge const and volatile flags of the incoming types. */
3541 result_type
3555 }
3556 \f
3557 /* Given a list of expressions, return a compound expression
3558 that performs them all and returns the value of the last of them. */
3560 tree
3562 tree list;
3563 {
3565 }
3567 static tree
3569 tree list;
3571 {
3572 tree rest;
3575 {
3576 /* Convert arrays and functions to pointers when there
3577 really is a comma operator. */
3583 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3585 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3588 #endif
3590 /* Don't let (0, 0) be null pointer constant. */
3594 }
3599 {
3600 /* The left-hand operand of a comma expression is like an expression
3601 statement: with -W or -Wunused, we should warn if it doesn't have
3602 any side-effects, unless it was explicitly cast to (void). */
3608 /* When pedantic, a compound expression can be neither an lvalue
3609 nor an integer constant expression. */
3612 }
3614 /* With -Wunused, we should also warn if the left-hand operand does have
3615 side-effects, but computes a value which is not used. For example, in
3616 `foo() + bar(), baz()' the result of the `+' operator is not used,
3617 so we should issue a warning. */
3622 }
3624 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3626 tree
3628 tree type;
3629 tree expr;
3630 {
3637 #if 0
3638 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3641 #endif
3644 {
3647 }
3650 {
3653 }
3656 {
3658 {
3662 }
3663 }
3665 {
3666 tree field;
3675 {
3677 tree t;
3682 {
3685 else
3687 }
3688 else
3694 }
3697 }
3698 else
3699 {
3702 /* If casting to void, avoid the error that would come
3703 from default_conversion in the case of a non-lvalue array. */
3707 /* Convert functions and arrays to pointers,
3708 but don't convert any other types. */
3712 /* Optionally warn about potentially worrisome casts. */
3717 {
3723 /* Check that the qualifiers on IN_TYPE are a superset of
3724 the qualifiers of IN_OTYPE. The outermost level of
3725 POINTER_TYPE nodes is uninteresting and we stop as soon
3726 as we hit a non-POINTER_TYPE node on either type. */
3727 do
3728 {
3732 /* GNU C allows cv-qualified function types. 'const'
3733 means the function is very pure, 'volatile' means it
3734 can't return. We need to warn when such qualifiers
3735 are added, not when they're taken away. */
3739 else
3741 }
3749 /* There are qualifiers present in IN_OTYPE that are not
3750 present in IN_TYPE. */
3752 }
3754 /* Warn about possible alignment problems. */
3760 /* Don't warn about opaque types, where the actual alignment
3761 restriction is unknown. */
3782 /* Don't warn about converting any constant. */
3789 /* Ignore any integer overflow caused by the cast. */
3791 {
3794 }
3795 }
3797 /* Pedantically, don't let (void *) (FOO *) 0 be a null pointer constant. */
3803 /* If pedantic, don't let a cast be an lvalue. */
3808 }
3810 /* Interpret a cast of expression EXPR to type TYPE. */
3811 tree
3814 {
3817 /* This avoids warnings about unprototyped casts on
3818 integers. E.g. "#define SIG_DFL (void(*)())0". */
3825 }
3827 \f
3828 /* Build an assignment expression of lvalue LHS from value RHS.
3829 MODIFYCODE is the code for a binary operator that we use
3830 to combine the old value of LHS with RHS to get the new value.
3831 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3833 tree
3837 {
3838 tree result;
3839 tree newrhs;
3843 /* Types that aren't fully specified cannot be used in assignments. */
3846 /* Avoid duplicate error messages from operands that had errors. */
3850 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3851 /* Do not use STRIP_NOPS here. We do not want an enumerator
3852 whose value is 0 to count as a null pointer constant. */
3858 /* Handle control structure constructs used as "lvalues". */
3861 {
3862 /* Handle (a, b) used as an "lvalue". */
3871 /* Handle (a ? b : c) used as an "lvalue". */
3875 {
3876 /* Produce (a ? (b = rhs) : (c = rhs))
3877 except that the RHS goes through a save-expr
3878 so the code to compute it is only emitted once. */
3879 tree cond
3887 /* Make sure the code to compute the rhs comes out
3888 before the split. */
3890 /* But cast it to void to avoid an "unused" error. */
3892 }
3895 }
3897 /* If a binary op has been requested, combine the old LHS value with the RHS
3898 producing the value we should actually store into the LHS. */
3901 {
3904 }
3906 /* Handle a cast used as an "lvalue".
3907 We have already performed any binary operator using the value as cast.
3908 Now convert the result to the cast type of the lhs,
3909 and then true type of the lhs and store it there;
3910 then convert result back to the cast type to be the value
3911 of the assignment. */
3914 {
3923 {
3925 tree result;
3933 }
3937 }
3939 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3940 Reject anything strange now. */
3945 /* Warn about storing in something that is `const'. */
3953 /* If storing into a structure or union member,
3954 it has probably been given type `int'.
3955 Compute the type that would go with
3956 the actual amount of storage the member occupies. */
3965 /* If storing in a field that is in actuality a short or narrower than one,
3966 we must store in the field in its actual type. */
3969 {
3972 }
3974 /* Convert new value to destination type. */
3981 /* Scan operands */
3986 /* If we got the LHS in a different type for storing in,
3987 convert the result back to the nominal type of LHS
3988 so that the value we return always has the same type
3989 as the LHS argument. */
3995 }
3996 \f
3997 /* Convert value RHS to type TYPE as preparation for an assignment
3998 to an lvalue of type TYPE.
3999 The real work of conversion is done by `convert'.
4000 The purpose of this function is to generate error messages
4001 for assignments that are not allowed in C.
4002 ERRTYPE is a string to use in error messages:
4003 "assignment", "return", etc. If it is null, this is parameter passing
4004 for a function call (and different error messages are output).
4006 FUNNAME is the name of the function being called,
4007 as an IDENTIFIER_NODE, or null.
4008 PARMNUM is the number of the argument, for printing in error messages. */
4010 static tree
4016 {
4018 tree rhstype;
4021 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4022 /* Do not use STRIP_NOPS here. We do not want an enumerator
4023 whose value is 0 to count as a null pointer constant. */
4040 {
4042 /* Check for Objective-C protocols. This will issue a warning if
4043 there are protocol violations. No need to use the return value. */
4046 }
4049 {
4052 }
4053 /* A type converts to a reference to it.
4054 This code doesn't fully support references, it's just for the
4055 special case of va_start and va_copy. */
4058 {
4060 {
4063 }
4068 /* We already know that these two types are compatible, but they
4069 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4070 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4071 likely to be va_list, a typedef to __builtin_va_list, which
4072 is different enough that it will cause problems later. */
4078 }
4079 /* Arithmetic types all interconvert, and enum is treated like int. */
4088 /* Conversion to a transparent union from its member types.
4089 This applies only to function arguments. */
4091 {
4092 tree memb_types;
4097 {
4108 {
4112 /* Any non-function converts to a [const][volatile] void *
4113 and vice versa; otherwise, targets must be the same.
4114 Meanwhile, the lhs target must have all the qualifiers of
4115 the rhs. */
4118 {
4119 /* If this type won't generate any warnings, use it. */
4129 /* Keep looking for a better type, but remember this one. */
4132 }
4133 }
4135 /* Can convert integer zero to any pointer type. */
4139 {
4142 }
4143 }
4146 {
4148 {
4149 /* We have only a marginally acceptable member type;
4150 it needs a warning. */
4154 /* Const and volatile mean something different for function
4155 types, so the usual warnings are not appropriate. */
4158 {
4159 /* Because const and volatile on functions are
4160 restrictions that say the function will not do
4161 certain things, it is okay to use a const or volatile
4162 function where an ordinary one is wanted, but not
4163 vice-versa. */
4167 }
4171 parmnum);
4172 }
4178 }
4179 }
4181 /* Conversions among pointers */
4184 {
4188 /* Any non-function converts to a [const][volatile] void *
4189 and vice versa; otherwise, targets must be the same.
4190 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4195 {
4198 ||
4200 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4201 which are not ANSI null ptr constants. */
4206 /* Const and volatile mean something different for function types,
4207 so the usual warnings are not appropriate. */
4210 {
4214 /* If this is not a case of ignoring a mismatch in signedness,
4215 no warning. */
4218 ;
4219 /* If there is a mismatch, do warn. */
4223 }
4226 {
4227 /* Because const and volatile on functions are restrictions
4228 that say the function will not do certain things,
4229 it is okay to use a const or volatile function
4230 where an ordinary one is wanted, but not vice-versa. */
4234 }
4235 }
4236 else
4240 }
4242 {
4243 /* An explicit constant 0 can convert to a pointer,
4244 or one that results from arithmetic, even including
4245 a cast to integer type. */
4247 &&
4252 {
4256 }
4258 }
4260 {
4264 }
4269 {
4271 {
4277 else
4280 }
4281 else
4283 parmnum);
4284 }
4285 else
4289 }
4291 /* Convert VALUE for assignment into inlined parameter PARM. */
4293 tree
4296 {
4299 /* If FN was prototyped, the value has been converted already
4300 in convert_arguments. */
4313 }
4315 /* Print a warning using MSGID.
4316 It gets OPNAME as its one parameter.
4317 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4318 FUNCTION and ARGNUM are handled specially if we are building an
4319 Objective-C selector. */
4321 static void
4325 tree function;
4327 {
4329 {
4334 {
4337 }
4339 {
4340 /* Function name is known; supply it. */
4347 }
4348 else
4349 {
4350 /* Function name unknown (call through ptr); just give arg number. */
4354 }
4356 }
4358 }
4359 \f
4360 /* If VALUE is a compound expr all of whose expressions are constant, then
4361 return its value. Otherwise, return error_mark_node.
4363 This is for handling COMPOUND_EXPRs as initializer elements
4364 which is allowed with a warning when -pedantic is specified. */
4366 static tree
4368 tree value;
4369 tree endtype;
4370 {
4372 {
4377 endtype);
4378 }
4382 else
4384 }
4385 \f
4386 /* Perform appropriate conversions on the initial value of a variable,
4387 store it in the declaration DECL,
4388 and print any error messages that are appropriate.
4389 If the init is invalid, store an ERROR_MARK. */
4391 void
4394 {
4397 /* If variable's type was invalidly declared, just ignore it. */
4403 /* Digest the specified initializer into an expression. */
4407 /* Store the expression if valid; else report error. */
4409 #if 0
4410 /* Note that this is the only place we can detect the error
4411 in a case such as struct foo bar = (struct foo) { x, y };
4412 where there is one initial value which is a constructor expression. */
4414 ;
4416 {
4419 }
4422 {
4425 }
4426 else
4427 {
4429 {
4434 }
4435 }
4436 #endif
4444 /* ANSI wants warnings about out-of-range constant initializers. */
4448 /* Check if we need to set array size from compound literal size. */
4452 {
4460 {
4464 {
4465 /* For int foo[] = (int [3]){1}; we need to set array size
4466 now since later on array initializer will be just the
4467 brace enclosed list of the compound literal. */
4471 }
4472 }
4473 }
4474 }
4475 \f
4476 /* Methods for storing and printing names for error messages. */
4478 /* Implement a spelling stack that allows components of a name to be pushed
4479 and popped. Each element on the stack is this structure. */
4481 struct spelling
4482 {
4484 union
4485 {
4489 };
4491 #define SPELLING_STRING 1
4492 #define SPELLING_MEMBER 2
4493 #define SPELLING_BOUNDS 3
4499 /* Macros to save and restore the spelling stack around push_... functions.
4500 Alternative to SAVE_SPELLING_STACK. */
4502 #define SPELLING_DEPTH() (spelling - spelling_base)
4503 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4505 /* Save and restore the spelling stack around arbitrary C code. */
4507 #define SAVE_SPELLING_DEPTH(code) \
4508 { \
4509 int __depth = SPELLING_DEPTH (); \
4510 code; \
4511 RESTORE_SPELLING_DEPTH (__depth); \
4512 }
4514 /* Push an element on the spelling stack with type KIND and assign VALUE
4515 to MEMBER. */
4517 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4518 { \
4519 int depth = SPELLING_DEPTH (); \
4520 \
4521 if (depth >= spelling_size) \
4522 { \
4523 spelling_size += 10; \
4524 if (spelling_base == 0) \
4525 spelling_base \
4526 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4527 else \
4528 spelling_base \
4529 = (struct spelling *) xrealloc (spelling_base, \
4530 spelling_size * sizeof (struct spelling)); \
4531 RESTORE_SPELLING_DEPTH (depth); \
4532 } \
4533 \
4534 spelling->kind = (KIND); \
4535 spelling->MEMBER = (VALUE); \
4536 spelling++; \
4537 }
4539 /* Push STRING on the stack. Printed literally. */
4541 static void
4544 {
4546 }
4548 /* Push a member name on the stack. Printed as '.' STRING. */
4550 static void
4552 tree decl;
4554 {
4558 }
4560 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4562 static void
4565 {
4567 }
4569 /* Compute the maximum size in bytes of the printed spelling. */
4571 static int
4573 {
4578 {
4581 else
4583 }
4586 }
4588 /* Print the spelling to BUFFER and return it. */
4593 {
4599 {
4602 }
4603 else
4604 {
4609 ;
4610 }
4613 }
4615 /* Issue an error message for a bad initializer component.
4616 MSGID identifies the message.
4617 The component name is taken from the spelling stack. */
4619 void
4622 {
4629 }
4631 /* Issue a pedantic warning for a bad initializer component.
4632 MSGID identifies the message.
4633 The component name is taken from the spelling stack. */
4635 void
4638 {
4645 }
4647 /* Issue a warning for a bad initializer component.
4648 MSGID identifies the message.
4649 The component name is taken from the spelling stack. */
4651 static void
4654 {
4661 }
4662 \f
4663 /* Digest the parser output INIT as an initializer for type TYPE.
4664 Return a C expression of type TYPE to represent the initial value.
4666 REQUIRE_CONSTANT requests an error if non-constant initializers or
4667 elements are seen. */
4669 static tree
4673 {
4682 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4683 /* Do not use STRIP_NOPS here. We do not want an enumerator
4684 whose value is 0 to count as a null pointer constant. */
4690 /* Initialization of an array of chars from a string constant
4691 optionally enclosed in braces. */
4694 {
4702 {
4710 {
4713 }
4717 {
4720 }
4726 /* Subtract 1 (or sizeof (wchar_t))
4727 because it's ok to ignore the terminating null char
4728 that is counted in the length of the constant. */
4739 }
4740 }
4742 /* Any type can be initialized
4743 from an expression of the same type, optionally with braces. */
4757 {
4763 {
4764 /* As an extension, allow initializing objects with static storage
4765 duration with compound literals (which are then treated just as
4766 the brace enclosed list they contain). */
4769 }
4773 {
4776 }
4781 /* Compound expressions can only occur here if -pedantic or
4782 -pedantic-errors is specified. In the later case, we always want
4783 an error. In the former case, we simply want a warning. */
4786 {
4787 inside_init
4792 else
4796 }
4799 /* This test catches things like `7 / 0' which
4800 result in an expression for which TREE_CONSTANT
4801 is true, but which is not actually something
4802 that is a legal constant. We really should not
4803 be using this function, because it is a part of
4804 the back-end. Instead, the expression should
4805 already have been turned into ERROR_MARK_NODE. */
4808 {
4811 }
4814 }
4816 /* Handle scalar types, including conversions. */
4820 {
4821 /* Note that convert_for_assignment calls default_conversion
4822 for arrays and functions. We must not call it in the
4823 case where inside_init is a null pointer constant. */
4824 inside_init
4829 {
4832 }
4835 {
4838 }
4841 }
4843 /* Come here only for records and arrays. */
4846 {
4849 }
4853 }
4854 \f
4855 /* Handle initializers that use braces. */
4857 /* Type of object we are accumulating a constructor for.
4858 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4861 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4862 left to fill. */
4865 /* For an ARRAY_TYPE, this is the specified index
4866 at which to store the next element we get. */
4869 /* For an ARRAY_TYPE, this is the maximum index. */
4872 /* For a RECORD_TYPE, this is the first field not yet written out. */
4875 /* For an ARRAY_TYPE, this is the index of the first element
4876 not yet written out. */
4879 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4880 This is so we can generate gaps between fields, when appropriate. */
4883 /* If we are saving up the elements rather than allocating them,
4884 this is the list of elements so far (in reverse order,
4885 most recent first). */
4888 /* 1 if constructor should be incrementally stored into a constructor chain,
4889 0 if all the elements should be kept in AVL tree. */
4892 /* 1 if so far this constructor's elements are all compile-time constants. */
4895 /* 1 if so far this constructor's elements are all valid address constants. */
4898 /* 1 if this constructor is erroneous so far. */
4901 /* 1 if have called defer_addressed_constants. */
4904 /* Structure for managing pending initializer elements, organized as an
4905 AVL tree. */
4907 struct init_node
4908 {
4912 tree purpose;
4913 tree value;
4914 };
4916 /* Tree of pending elements at this constructor level.
4917 These are elements encountered out of order
4918 which belong at places we haven't reached yet in actually
4919 writing the output.
4920 Will never hold tree nodes across GC runs. */
4923 /* The SPELLING_DEPTH of this constructor. */
4926 /* 0 if implicitly pushing constructor levels is allowed. */
4932 /* DECL node for which an initializer is being read.
4933 0 means we are reading a constructor expression
4934 such as (struct foo) {...}. */
4937 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4940 /* Nonzero if this is an initializer for a top-level decl. */
4943 /* Nonzero if there were any member designators in this initializer. */
4946 /* Nesting depth of designator list. */
4949 /* Nonzero if there were diagnosed errors in this designator list. */
4952 \f
4953 /* This stack has a level for each implicit or explicit level of
4954 structuring in the initializer, including the outermost one. It
4955 saves the values of most of the variables above. */
4959 struct constructor_stack
4960 {
4962 tree type;
4963 tree fields;
4964 tree index;
4965 tree max_index;
4966 tree unfilled_index;
4967 tree unfilled_fields;
4968 tree bit_index;
4969 tree elements;
4973 /* If nonzero, this value should replace the entire
4974 constructor at this level. */
4975 tree replacement_value;
4984 };
4988 /* This stack represents designators from some range designator up to
4989 the last designator in the list. */
4991 struct constructor_range_stack
4992 {
4995 tree range_start;
4996 tree index;
4997 tree range_end;
4998 tree fields;
4999 };
5003 /* This stack records separate initializers that are nested.
5004 Nested initializers can't happen in ANSI C, but GNU C allows them
5005 in cases like { ... (struct foo) { ... } ... }. */
5007 struct initializer_stack
5008 {
5010 tree decl;
5014 tree elements;
5022 };
5025 \f
5026 /* Prepare to parse and output the initializer for variable DECL. */
5028 void
5030 tree decl;
5031 tree asmspec_tree;
5033 {
5064 {
5066 require_constant_elements
5068 /* For a scalar, you can always use any value to initialize,
5069 even within braces. */
5075 }
5076 else
5077 {
5081 }
5094 }
5096 void
5098 {
5101 /* Output subconstants (string constants, usually)
5102 that were referenced within this initializer and saved up.
5103 Must do this if and only if we called defer_addressed_constants. */
5107 /* Free the whole constructor stack of this initializer. */
5109 {
5113 }
5118 /* Pop back to the data of the outer initializer (if any). */
5133 }
5134 \f
5135 /* Call here when we see the initializer is surrounded by braces.
5136 This is instead of a call to push_init_level;
5137 it is matched by a call to pop_init_level.
5139 TYPE is the type to initialize, for a constructor expression.
5140 For an initializer for a decl, TYPE is zero. */
5142 void
5144 tree type;
5145 {
5187 {
5189 /* Skip any nameless bit fields at the beginning. */
5196 }
5198 {
5200 {
5201 constructor_max_index
5204 /* Detect non-empty initializations of zero-length arrays. */
5209 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5210 to initialize VLAs will cause an proper error; avoid tree
5211 checking errors as well by setting a safe value. */
5216 constructor_index
5219 }
5220 else
5224 }
5226 {
5227 /* Vectors are like simple fixed-size arrays. */
5228 constructor_max_index =
5232 }
5233 else
5234 {
5235 /* Handle the case of int x = {5}; */
5238 }
5239 }
5240 \f
5241 /* Push down into a subobject, for initialization.
5242 If this is for an explicit set of braces, IMPLICIT is 0.
5243 If it is because the next element belongs at a lower level,
5244 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5246 void
5249 {
5253 /* If we've exhausted any levels that didn't have braces,
5254 pop them now. */
5256 {
5264 else
5266 }
5268 /* Unless this is an explicit brace, we need to preserve previous
5269 content if any. */
5271 {
5278 }
5311 {
5316 }
5318 /* Don't die if an entire brace-pair level is superfluous
5319 in the containing level. */
5321 ;
5324 {
5325 /* Don't die if there are extra init elts at the end. */
5328 else
5329 {
5332 constructor_depth++;
5333 }
5334 }
5336 {
5339 constructor_depth++;
5340 }
5343 {
5348 }
5351 {
5359 }
5362 {
5365 }
5369 {
5371 /* Skip any nameless bit fields at the beginning. */
5378 }
5380 {
5381 /* Vectors are like simple fixed-size arrays. */
5382 constructor_max_index =
5386 }
5388 {
5390 {
5391 constructor_max_index
5394 /* Detect non-empty initializations of zero-length arrays. */
5399 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5400 to initialize VLAs will cause an proper error; avoid tree
5401 checking errors as well by setting a safe value. */
5406 constructor_index
5409 }
5410 else
5415 {
5416 /* We need to split the char/wchar array into individual
5417 characters, so that we don't have to special case it
5418 everywhere. */
5420 }
5421 }
5422 else
5423 {
5427 }
5428 }
5430 /* At the end of an implicit or explicit brace level,
5431 finish up that level of constructor.
5432 If we were outputting the elements as they are read, return 0
5433 from inner levels (process_init_element ignores that),
5434 but return error_mark_node from the outermost level
5435 (that's what we want to put in DECL_INITIAL).
5436 Otherwise, return a CONSTRUCTOR expression. */
5438 tree
5441 {
5446 {
5447 /* When we come to an explicit close brace,
5448 pop any inner levels that didn't have explicit braces. */
5454 }
5458 /* Error for initializing a flexible array member, or a zero-length
5459 array member in an inappropriate context. */
5464 {
5465 /* Silently discard empty initializations. The parser will
5466 already have pedwarned for empty brackets. */
5470 {
5476 /* We have already issued an error message for the existence
5477 of a flexible array member not at the end of the structure.
5478 Discard the initializer so that we do not abort later. */
5481 }
5482 else
5483 /* Zero-length arrays are no longer special, so we should no longer
5484 get here. */
5486 }
5488 /* Warn when some struct elements are implicitly initialized to zero. */
5490 && constructor_type
5493 {
5494 /* Do not warn for flexible array members or zero-length arrays. */
5500 /* Do not warn if this level of the initializer uses member
5501 designators; it is likely to be deliberate. */
5503 {
5507 }
5508 }
5510 /* Now output all pending elements. */
5514 /* Pad out the end of the structure. */
5516 /* If this closes a superfluous brace pair,
5517 just pass out the element between them. */
5520 ;
5525 {
5526 /* A nonincremental scalar initializer--just return
5527 the element, after verifying there is just one. */
5529 {
5533 }
5535 {
5538 }
5539 else
5541 }
5542 else
5543 {
5546 else
5547 {
5554 }
5555 }
5580 {
5584 }
5586 }
5588 /* Common handling for both array range and field name designators.
5589 ARRAY argument is non-zero for array ranges. Returns zero for success. */
5591 static int
5594 {
5595 tree subtype;
5598 /* Don't die if an entire brace-pair level is superfluous
5599 in the containing level. */
5603 /* If there were errors in this designator list already, bail out silently. */
5608 {
5612 /* Designator list starts at the level of closest explicit
5613 braces. */
5618 }
5621 {
5624 }
5628 {
5632 }
5634 {
5636 }
5637 else
5642 {
5645 }
5647 {
5650 }
5655 }
5657 /* If there are range designators in designator list, push a new designator
5658 to constructor_range_stack. RANGE_END is end of such stack range or
5659 NULL_TREE if there is no range designator at this level. */
5661 static void
5663 tree range_end;
5664 {
5679 }
5681 /* Within an array initializer, specify the next index to be initialized.
5682 FIRST is that index. If LAST is nonzero, then initialize a range
5683 of indices, running from FIRST through LAST. */
5685 void
5688 {
5718 else
5719 {
5723 {
5727 {
5730 }
5731 else
5732 {
5736 {
5739 }
5740 }
5741 }
5743 designator_depth++;
5747 }
5748 }
5750 /* Within a struct initializer, specify the next field to be initialized. */
5752 void
5754 tree fieldname;
5755 {
5756 tree tail;
5765 {
5768 }
5772 {
5775 }
5780 else
5781 {
5783 designator_depth++;
5787 }
5788 }
5789 \f
5790 /* Add a new initializer to the tree of pending initializers. PURPOSE
5791 identifies the initializer, either array index or field in a structure.
5792 VALUE is the value of that index or field. */
5794 static void
5797 {
5804 {
5806 {
5812 else
5813 {
5818 }
5819 }
5820 }
5821 else
5822 {
5823 tree bitpos;
5827 {
5833 else
5834 {
5839 }
5840 }
5841 }
5854 {
5858 {
5862 {
5864 {
5865 /* L rotation. */
5878 {
5881 else
5883 }
5884 else
5886 }
5887 else
5888 {
5889 /* LR rotation. */
5911 {
5914 else
5916 }
5917 else
5919 }
5921 }
5922 else
5923 {
5924 /* p->balance == +1; growth of left side balances the node. */
5927 }
5928 }
5930 {
5932 /* Growth propagation from right side. */
5935 {
5937 {
5938 /* R rotation. */
5951 {
5954 else
5956 }
5957 else
5959 }
5961 {
5962 /* RL rotation */
5984 {
5987 else
5989 }
5990 else
5992 }
5994 }
5995 else
5996 {
5997 /* p->balance == -1; growth of right side balances the node. */
6000 }
6001 }
6005 }
6006 }
6008 /* Build AVL tree from a sorted chain. */
6010 static void
6012 {
6013 tree chain;
6023 {
6025 /* Skip any nameless bit fields at the beginning. */
6031 }
6033 {
6035 constructor_unfilled_index
6038 else
6040 }
6042 }
6044 /* Build AVL tree from a string constant. */
6046 static void
6048 tree str;
6049 {
6064 else
6075 {
6077 {
6080 }
6081 else
6082 {
6086 {
6089 else
6094 }
6095 }
6098 {
6101 {
6103 {
6106 }
6107 }
6109 {
6112 }
6117 }
6122 }
6125 }
6127 /* Return value of FIELD in pending initializer or zero if the field was
6128 not initialized yet. */
6130 static tree
6132 tree field;
6133 {
6137 {
6144 {
6149 else
6151 }
6152 }
6154 {
6158 && (!constructor_unfilled_fields
6165 {
6170 else
6172 }
6173 }
6175 {
6179 }
6181 }
6183 /* "Output" the next constructor element.
6184 At top level, really output it to assembler code now.
6185 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6186 TYPE is the data type that the containing data type wants here.
6187 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6189 PENDING if non-nil means output pending elements that belong
6190 right after this element. (PENDING is normally 1;
6191 it is 0 while outputting pending elements, to avoid recursion.) */
6193 static void
6197 {
6209 {
6210 /* As an extension, allow initializing objects with static storage
6211 duration with compound literals (which are then treated just as
6212 the brace enclosed list they contain). */
6215 }
6229 {
6232 }
6237 /* If this field is empty (and not at the end of structure),
6238 don't do anything other than checking the initializer. */
6249 {
6252 }
6254 /* If this element doesn't come next in sequence,
6255 put it on constructor_pending_elts. */
6257 && (!constructor_incremental
6259 {
6266 }
6268 && (!constructor_incremental
6270 {
6271 /* We do this for records but not for unions. In a union,
6272 no matter which field is specified, it can be initialized
6273 right away since it starts at the beginning of the union. */
6275 {
6278 else
6279 {
6287 }
6288 }
6292 }
6295 {
6299 /* We can have just one union field set. */
6301 }
6303 /* Otherwise, output this element either to
6304 constructor_elements or to the assembler file. */
6308 constructor_elements
6311 /* Advance the variable that indicates sequential elements output. */
6313 constructor_unfilled_index
6315 bitsize_one_node);
6317 {
6318 constructor_unfilled_fields
6321 /* Skip any nameless bit fields. */
6325 constructor_unfilled_fields =
6327 }
6331 /* Now output any pending elements which have become next. */
6334 }
6336 /* Output any pending elements which have become next.
6337 As we output elements, constructor_unfilled_{fields,index}
6338 advances, which may cause other elements to become next;
6339 if so, they too are output.
6341 If ALL is 0, we return when there are
6342 no more pending elements to output now.
6344 If ALL is 1, we output space as necessary so that
6345 we can output all the pending elements. */
6347 static void
6350 {
6352 tree next;
6354 retry:
6356 /* Look thru the whole pending tree.
6357 If we find an element that should be output now,
6358 output it. Otherwise, set NEXT to the element
6359 that comes first among those still pending. */
6363 {
6365 {
6367 constructor_unfilled_index))
6373 {
6374 /* Advance to the next smaller node. */
6377 else
6378 {
6379 /* We have reached the smallest node bigger than the
6380 current unfilled index. Fill the space first. */
6383 }
6384 }
6385 else
6386 {
6387 /* Advance to the next bigger node. */
6390 else
6391 {
6392 /* We have reached the biggest node in a subtree. Find
6393 the parent of it, which is the next bigger node. */
6399 {
6402 }
6403 }
6404 }
6405 }
6408 {
6411 /* If the current record is complete we are done. */
6417 /* We can't compare fields here because there might be empty
6418 fields in between. */
6420 {
6424 }
6426 {
6427 /* Advance to the next smaller node. */
6430 else
6431 {
6432 /* We have reached the smallest node bigger than the
6433 current unfilled field. Fill the space first. */
6436 }
6437 }
6438 else
6439 {
6440 /* Advance to the next bigger node. */
6443 else
6444 {
6445 /* We have reached the biggest node in a subtree. Find
6446 the parent of it, which is the next bigger node. */
6453 {
6456 }
6457 }
6458 }
6459 }
6460 }
6462 /* Ordinarily return, but not if we want to output all
6463 and there are elements left. */
6467 /* If it's not incremental, just skip over the gap, so that after
6468 jumping to retry we will output the next successive element. */
6475 /* ELT now points to the node in the pending tree with the next
6476 initializer to output. */
6478 }
6479 \f
6480 /* Add one non-braced element to the current constructor level.
6481 This adjusts the current position within the constructor's type.
6482 This may also start or terminate implicit levels
6483 to handle a partly-braced initializer.
6485 Once this has found the correct level for the new element,
6486 it calls output_init_element. */
6488 void
6490 tree value;
6491 {
6498 /* Handle superfluous braces around string cst as in
6499 char x[] = {"foo"}; */
6501 && constructor_type
6505 {
6510 }
6513 {
6516 }
6518 /* Ignore elements of a brace group if it is entirely superfluous
6519 and has already been diagnosed. */
6523 /* If we've exhausted any levels that didn't have braces,
6524 pop them now. */
6526 {
6534 constructor_index)))
6536 else
6538 }
6540 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6542 {
6543 /* If value is a compound literal and we'll be just using its
6544 content, don't put it into a SAVE_EXPR. */
6546 || !require_constant_value
6549 }
6552 {
6554 {
6555 tree fieldtype;
6559 {
6562 }
6569 /* Error for non-static initialization of a flexible array member. */
6571 && !require_constant_value
6574 {
6577 }
6579 /* Accept a string constant to initialize a subarray. */
6585 /* Otherwise, if we have come to a subaggregate,
6586 and we don't have an element of its type, push into it. */
6592 {
6595 }
6598 {
6602 }
6603 else
6604 /* Do the bookkeeping for an element that was
6605 directly output as a constructor. */
6606 {
6607 /* For a record, keep track of end position of last field. */
6609 constructor_bit_index
6615 /* Skip any nameless bit fields. */
6619 constructor_unfilled_fields =
6621 }
6624 /* Skip any nameless bit fields at the beginning. */
6629 }
6631 {
6632 tree fieldtype;
6636 {
6639 }
6646 /* Warn that traditional C rejects initialization of unions.
6647 We skip the warning if the value is zero. This is done
6648 under the assumption that the zero initializer in user
6649 code appears conditioned on e.g. __STDC__ to avoid
6650 "missing initializer" warnings and relies on default
6651 initialization to zero in the traditional C case.
6652 We also skip the warning if the initializer is designated,
6653 again on the assumption that this must be conditional on
6654 __STDC__ anyway (and we've already complained about the
6655 member-designator already). */
6660 /* Accept a string constant to initialize a subarray. */
6666 /* Otherwise, if we have come to a subaggregate,
6667 and we don't have an element of its type, push into it. */
6673 {
6676 }
6679 {
6683 }
6684 else
6685 /* Do the bookkeeping for an element that was
6686 directly output as a constructor. */
6687 {
6690 }
6693 }
6695 {
6699 /* Accept a string constant to initialize a subarray. */
6705 /* Otherwise, if we have come to a subaggregate,
6706 and we don't have an element of its type, push into it. */
6712 {
6715 }
6720 {
6723 }
6725 /* Now output the actual element. */
6727 {
6731 }
6733 constructor_index
6737 /* If we are doing the bookkeeping for an element that was
6738 directly output as a constructor, we must update
6739 constructor_unfilled_index. */
6741 }
6743 {
6746 /* Do a basic check of initializer size. Note that vectors
6747 always have a fixed size derived from their type. */
6749 {
6752 }
6754 /* Now output the actual element. */
6758 constructor_index
6762 /* If we are doing the bookkeeping for an element that was
6763 directly output as a constructor, we must update
6764 constructor_unfilled_index. */
6766 }
6768 /* Handle the sole element allowed in a braced initializer
6769 for a scalar variable. */
6771 {
6774 }
6775 else
6776 {
6780 }
6782 /* Handle range initializers either at this level or anywhere higher
6783 in the designator stack. */
6785 {
6792 {
6796 }
6800 {
6804 }
6811 {
6815 {
6818 }
6826 }
6831 }
6834 }
6837 }
6838 \f
6839 /* Build a simple asm-statement, from one string literal. */
6840 tree
6842 tree expr;
6843 {
6850 {
6851 tree stmt;
6855 NULL_TREE));
6858 }
6862 }
6864 /* Build an asm-statement, whose components are a CV_QUALIFIER, a
6865 STRING, some OUTPUTS, some INPUTS, and some CLOBBERS. */
6867 tree
6869 tree cv_qualifier;
6870 tree string;
6871 tree outputs;
6872 tree inputs;
6873 tree clobbers;
6874 {
6875 tree tail;
6878 {
6881 }
6885 {
6889 }
6891 /* We can remove output conversions that change the type,
6892 but not the mode. */
6894 {
6900 /* Allow conversions as LHS here. build_modify_expr as called below
6901 will do the right thing with them. */
6912 }
6914 /* Remove output conversions that change the type but not the mode. */
6916 {
6920 }
6922 /* Perform default conversions on array and function inputs.
6923 Don't do this for other types as it would screw up operands
6924 expected to be in memory. */
6930 }
6932 /* Expand an ASM statement with operands, handling output operands
6933 that are not variables or INDIRECT_REFS by transforming such
6934 cases into cases that expand_asm_operands can handle.
6936 Arguments are same as for expand_asm_operands. */
6938 void
6944 {
6947 /* o[I] is the place that output number I should be written. */
6949 tree tail;
6951 /* Record the contents of OUTPUTS before it is modified. */
6955 /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of
6956 OUTPUTS some trees for where the values were actually stored. */
6959 /* Copy all the intermediate outputs into the specified outputs. */
6961 {
6963 {
6968 /* Restore the original value so that it's correct the next
6969 time we expand this function. */
6971 }
6972 /* Detect modification of read-only values.
6973 (Otherwise done by build_modify_expr.) */
6974 else
6975 {
6983 }
6984 }
6986 /* Those MODIFY_EXPRs could do autoincrements. */
6988 }
6989 \f
6990 /* Expand a C `return' statement.
6991 RETVAL is the expression for what to return,
6992 or a null pointer for `return;' with no value. */
6994 tree
6996 tree retval;
6997 {
7004 {
7009 }
7011 {
7015 }
7016 else
7017 {
7021 tree inner;
7029 /* Strip any conversions, additions, and subtractions, and see if
7030 we are returning the address of a local variable. Warn if so. */
7032 {
7034 {
7041 /* If the second operand of the MINUS_EXPR has a pointer
7042 type (or is converted from it), this may be valid, so
7043 don't give a warning. */
7044 {
7058 }
7075 }
7078 }
7081 }
7084 }
7085 \f
7087 /* The SWITCH_STMT being built. */
7088 tree switch_stmt;
7089 /* A splay-tree mapping the low element of a case range to the high
7090 element, or NULL_TREE if there is no high element. Used to
7091 determine whether or not a new case label duplicates an old case
7092 label. We need a tree, rather than simply a hash table, because
7093 of the GNU case range extension. */
7094 splay_tree cases;
7095 /* The next node on the stack. */
7097 };
7099 /* A stack of the currently active switch statements. The innermost
7100 switch statement is on the top of the stack. There is no need to
7101 mark the stack for garbage collection because it is only active
7102 during the processing of the body of a function, and we never
7103 collect at that point. */
7107 /* Start a C switch statement, testing expression EXP. Return the new
7108 SWITCH_STMT. */
7110 tree
7112 tree exp;
7113 {
7119 {
7125 {
7128 }
7129 else
7130 {
7140 }
7141 }
7143 /* Add this new SWITCH_STMT to the stack. */
7151 }
7153 /* Process a case label. */
7155 tree
7157 tree low_value;
7158 tree high_value;
7159 {
7163 {
7169 }
7172 else
7176 }
7178 /* Finish the switch statement. */
7180 void
7182 {
7187 /* Pop the stack. */
7191 }