| blob | ce37eea09f74ebeb1cedef66be4ed4e1f51a81b5 |
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). */
48 /* Nonzero if we've already printed a "missing braces around initializer"
49 message within this initializer. */
52 /* 1 if we explained undeclared var errors. */
87 \f
88 /* Do `exp = require_complete_type (exp);' to make sure exp
89 does not have an incomplete type. (That includes void types.) */
91 tree
93 tree value;
94 {
100 /* First, detect a valid value with a complete type. */
106 }
108 /* Print an error message for invalid use of an incomplete type.
109 VALUE is the expression that was used (or 0 if that isn't known)
110 and TYPE is the type that was invalid. */
112 void
114 tree value;
115 tree type;
116 {
119 /* Avoid duplicate error message. */
127 else
128 {
129 retry:
130 /* We must print an error message. Be clever about what it says. */
133 {
152 {
154 {
157 }
160 }
166 }
171 else
172 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
175 }
176 }
178 /* Given a type, apply default promotions wrt unnamed function
179 arguments and return the new type. */
181 tree
183 tree type;
184 {
189 {
190 /* Preserve unsignedness if not really getting any wider. */
195 }
198 }
200 /* Return a variant of TYPE which has all the type qualifiers of LIKE
201 as well as those of TYPE. */
203 static tree
206 {
209 }
210 \f
211 /* Return the common type of two types.
212 We assume that comptypes has already been done and returned 1;
213 if that isn't so, this may crash. In particular, we assume that qualifiers
214 match.
216 This is the type for the result of most arithmetic operations
217 if the operands have the given two types. */
219 tree
222 {
225 tree attributes;
227 /* Save time if the two types are the same. */
231 /* If one type is nonsense, use the other. */
237 /* Merge the attributes. */
240 /* Treat an enum type as the unsigned integer type of the same width. */
250 /* If one type is complex, form the common type of the non-complex
251 components, then make that complex. Use T1 or T2 if it is the
252 required type. */
254 {
263 else
265 attributes);
266 }
269 {
272 /* If only one is real, use it as the result. */
280 /* Both real or both integers; use the one with greater precision. */
287 /* Same precision. Prefer longs to ints even when same size. */
292 attributes);
296 {
297 /* But preserve unsignedness from the other type,
298 since long cannot hold all the values of an unsigned int. */
301 else
304 }
306 /* Likewise, prefer long double to double even if same size. */
310 attributes);
312 /* Otherwise prefer the unsigned one. */
316 else
320 /* For two pointers, do this recursively on the target type,
321 and combine the qualifiers of the two types' targets. */
322 /* This code was turned off; I don't know why.
323 But ANSI C specifies doing this with the qualifiers.
324 So I turned it on again. */
325 {
335 }
336 #if 0
339 #endif
342 {
344 /* Save space: see if the result is identical to one of the args. */
349 /* Merge the element types, and have a size if either arg has one. */
352 }
355 /* Function types: prefer the one that specified arg types.
356 If both do, merge the arg types. Also merge the return types. */
357 {
365 /* Save space: see if the result is identical to one of the args. */
371 /* Simple way if one arg fails to specify argument types. */
373 {
376 }
378 {
381 }
383 /* If both args specify argument types, we must merge the two
384 lists, argument by argument. */
399 {
400 /* A null type means arg type is not specified.
401 Take whatever the other function type has. */
403 {
406 }
408 {
411 }
413 /* Given wait (union {union wait *u; int *i} *)
414 and wait (union wait *),
415 prefer union wait * as type of parm. */
418 {
419 tree memb;
423 {
428 }
429 }
432 {
433 tree memb;
437 {
442 }
443 }
445 parm_done: ;
446 }
451 /* ... falls through ... */
452 }
456 }
458 }
459 \f
460 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
461 or various other operations. Return 2 if they are compatible
462 but a warning may be needed if you use them together. */
464 int
467 {
472 /* Suppress errors caused by previously reported errors. */
478 /* If either type is the internal version of sizetype, return the
479 language version. */
488 /* Treat an enum type as the integer type of the same width and
489 signedness. */
499 /* Different classes of types can't be compatible. */
503 /* Qualifiers must match. */
508 /* Allow for two different type nodes which have essentially the same
509 definition. Note that we already checked for equality of the type
510 qualifiers (just above). */
515 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
519 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
523 {
534 {
541 /* Target types must match incl. qualifiers. */
546 /* Sizes must match unless one is missing or variable. */
553 d1_variable = (! d1_zero
556 d2_variable = (! d2_zero
570 }
578 /* The target might allow certain vector types to be compatible. */
585 }
587 }
589 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
590 ignoring their qualifiers. REFLEXIVE is only used by ObjC - set it
591 to 1 or 0 depending if the check of the pointer types is meant to
592 be reflexive or not (typically, assignments are not reflexive,
593 while comparisons are reflexive).
594 */
596 static int
600 {
603 /* Give objc_comptypes a crack at letting these types through. */
613 }
614 \f
615 /* Subroutines of `comptypes'. */
617 /* Return 1 if two function types F1 and F2 are compatible.
618 If either type specifies no argument types,
619 the other must specify a fixed number of self-promoting arg types.
620 Otherwise, if one type specifies only the number of arguments,
621 the other must specify that number of self-promoting arg types.
622 Otherwise, the argument types must match. */
624 static int
627 {
629 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
640 /* An unspecified parmlist matches any specified parmlist
641 whose argument types don't need default promotions. */
644 {
647 /* If one of these types comes from a non-prototype fn definition,
648 compare that with the other type's arglist.
649 If they don't match, ask for a warning (but no error). */
654 }
656 {
663 }
665 /* Both types have argument lists: compare them and propagate results. */
668 }
670 /* Check two lists of types for compatibility,
671 returning 0 for incompatible, 1 for compatible,
672 or 2 for compatible with warning. */
674 static int
677 {
678 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
683 {
686 /* If one list is shorter than the other,
687 they fail to match. */
690 /* A null pointer instead of a type
691 means there is supposed to be an argument
692 but nothing is specified about what type it has.
693 So match anything that self-promotes. */
695 {
698 }
700 {
703 }
706 {
707 /* Allow wait (union {union wait *u; int *i} *)
708 and wait (union wait *) to be compatible. */
715 {
716 tree memb;
723 }
730 {
731 tree memb;
738 }
739 else
741 }
743 /* comptypes said ok, but record if it said to warn. */
749 }
750 }
751 \f
752 /* Compute the size to increment a pointer by. */
754 tree
756 tree type;
757 {
764 {
767 }
769 /* Convert in case a char is more than one unit. */
773 }
774 \f
775 /* Return either DECL or its known constant value (if it has one). */
777 tree
779 tree decl;
780 {
782 in a place where a variable is invalid. */
788 /* This is invalid if initial value is not constant.
789 If it has either a function call, a memory reference,
790 or a variable, then re-evaluating it could give different results. */
792 /* Check for cases where this is sub-optimal, even though valid. */
796 }
798 /* Return either DECL or its known constant value (if it has one), but
799 return DECL if pedantic or DECL has mode BLKmode. This is for
800 bug-compatibility with the old behavior of decl_constant_value
801 (before GCC 3.0); every use of this function is a bug and it should
802 be removed before GCC 3.1. It is not appropriate to use pedantic
803 in a way that affects optimization, and BLKmode is probably not the
804 right test for avoiding misoptimizations either. */
806 static tree
808 tree decl;
809 {
812 else
814 }
817 /* Perform the default conversion of arrays and functions to pointers.
818 Return the result of converting EXP. For any other expression, just
819 return EXP. */
821 static tree
823 tree exp;
824 {
825 tree orig_exp;
830 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
831 an lvalue.
833 Do not use STRIP_NOPS here! It will remove conversions from pointer
834 to integer and cause infinite recursion. */
839 {
843 }
845 /* Preserve the original expression code. */
850 {
852 }
854 {
855 tree adr;
857 tree ptrtype;
863 {
866 }
869 restype
880 {
884 }
888 {
889 /* Before C99, non-lvalue arrays do not decay to pointers.
890 Normally, using such an array would be invalid; but it can
891 be used correctly inside sizeof or as a statement expression.
892 Thus, do not give an error here; an error will result later. */
894 }
899 {
900 /* ??? This is not really quite correct
901 in that the type of the operand of ADDR_EXPR
902 is not the target type of the type of the ADDR_EXPR itself.
903 Question is, can this lossage be avoided? */
910 }
911 /* This way is better for a COMPONENT_REF since it can
912 simplify the offset for a component. */
915 }
917 }
919 /* Perform default promotions for C data used in expressions.
920 Arrays and functions are converted to pointers;
921 enumeral types or short or char, to int.
922 In addition, manifest constants symbols are replaced by their values. */
924 tree
926 tree exp;
927 {
928 tree orig_exp;
935 /* Constants can be used directly unless they're not loadable. */
939 /* Replace a nonvolatile const static variable with its value unless
940 it is an array, in which case we must be sure that taking the
941 address of the array produces consistent results. */
943 {
946 }
948 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
949 an lvalue.
951 Do not use STRIP_NOPS here! It will remove conversions from pointer
952 to integer and cause infinite recursion. */
959 /* Preserve the original expression code. */
963 /* Normally convert enums to int,
964 but convert wide enums to something wider. */
966 {
974 }
978 /* If it's thinner than an int, promote it like a
979 c_promoting_integer_type_p, otherwise leave it alone. */
985 {
986 /* Preserve unsignedness if not really getting any wider. */
992 }
995 {
998 }
1000 }
1001 \f
1002 /* Look up COMPONENT in a structure or union DECL.
1004 If the component name is not found, returns NULL_TREE. Otherwise,
1005 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1006 stepping down the chain to the component, which is in the last
1007 TREE_VALUE of the list. Normally the list is of length one, but if
1008 the component is embedded within (nested) anonymous structures or
1009 unions, the list steps down the chain to the component. */
1011 static tree
1014 {
1016 tree field;
1018 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1019 to the field elements. Use a binary search on this array to quickly
1020 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1021 will always be set for structures which have many elements. */
1024 {
1032 {
1037 {
1038 /* Step through all anon unions in linear fashion. */
1040 {
1044 {
1049 }
1050 }
1052 /* Entire record is only anon unions. */
1056 /* Restart the binary search, with new lower bound. */
1058 }
1064 else
1066 }
1072 }
1073 else
1074 {
1076 {
1080 {
1085 }
1089 }
1093 }
1096 }
1098 /* Make an expression to refer to the COMPONENT field of
1099 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1101 tree
1104 {
1108 tree ref;
1110 /* If DATUM is a COMPOUND_EXPR, move our reference inside it.
1111 If pedantic ensure that the arguments are not lvalues; otherwise,
1112 if the component is an array, it would wrongly decay to a pointer in
1113 C89 mode.
1114 We cannot do this with a COND_EXPR, because in a conditional expression
1115 the default promotions are applied to both sides, and this would yield
1116 the wrong type of the result; for example, if the components have
1117 type "char". */
1119 {
1121 {
1125 }
1128 }
1130 /* See if there is a field or component with name COMPONENT. */
1133 {
1135 {
1138 }
1143 {
1148 }
1150 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1151 This might be better solved in future the way the C++ front
1152 end does it - by giving the anonymous entities each a
1153 separate name and type, and then have build_component_ref
1154 recursively call itself. We can't do that here. */
1155 do
1156 {
1174 }
1178 }
1184 }
1185 \f
1186 /* Given an expression PTR for a pointer, return an expression
1187 for the value pointed to.
1188 ERRORSTRING is the name of the operator to appear in error messages. */
1190 tree
1192 tree ptr;
1194 {
1199 {
1204 else
1205 {
1210 {
1213 }
1217 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1218 so that we get the proper error message if the result is used
1219 to assign to. Also, &* is supposed to be a no-op.
1220 And ANSI C seems to specify that the type of the result
1221 should be the const type. */
1222 /* A de-reference of a pointer to const is not a const. It is valid
1223 to change it via some other pointer. */
1229 }
1230 }
1234 }
1236 /* This handles expressions of the form "a[i]", which denotes
1237 an array reference.
1239 This is logically equivalent in C to *(a+i), but we may do it differently.
1240 If A is a variable or a member, we generate a primitive ARRAY_REF.
1241 This avoids forcing the array out of registers, and can work on
1242 arrays that are not lvalues (for example, members of structures returned
1243 by functions). */
1245 tree
1248 {
1250 {
1253 }
1261 {
1264 /* Subscripting with type char is likely to lose
1265 on a machine where chars are signed.
1266 So warn on any machine, but optionally.
1267 Don't warn for unsigned char since that type is safe.
1268 Don't warn for signed char because anyone who uses that
1269 must have done so deliberately. */
1274 /* Apply default promotions *after* noticing character types. */
1277 /* Require integer *after* promotion, for sake of enums. */
1279 {
1282 }
1284 /* An array that is indexed by a non-constant
1285 cannot be stored in a register; we must be able to do
1286 address arithmetic on its address.
1287 Likewise an array of elements of variable size. */
1291 {
1294 }
1295 /* An array that is indexed by a constant value which is not within
1296 the array bounds cannot be stored in a register either; because we
1297 would get a crash in store_bit_field/extract_bit_field when trying
1298 to access a non-existent part of the register. */
1302 {
1305 }
1308 {
1316 }
1320 /* Array ref is const/volatile if the array elements are
1321 or if the array is. */
1330 /* This was added by rms on 16 Nov 91.
1331 It fixes vol struct foo *a; a->elts[1]
1332 in an inline function.
1333 Hope it doesn't break something else. */
1336 }
1338 {
1342 /* Do the same warning check as above, but only on the part that's
1343 syntactically the index and only if it is also semantically
1344 the index. */
1350 /* Put the integer in IND to simplify error checking. */
1352 {
1356 }
1363 {
1366 }
1368 {
1371 }
1375 }
1376 }
1377 \f
1378 /* Build an external reference to identifier ID. FUN indicates
1379 whether this will be used for a function call. */
1380 tree
1382 tree id;
1384 {
1385 tree ref;
1393 {
1397 {
1399 /* Ordinary implicit function declaration. */
1401 else
1402 {
1403 /* Implicit declaration of built-in function. Don't
1404 change the built-in declaration, but don't let this
1405 go by silently, either. */
1408 /* only issue this warning once */
1411 }
1412 }
1413 else
1414 {
1415 /* Don't complain about something that's already been
1416 complained about. */
1420 /* Reference to undeclared variable, including reference to
1421 builtin outside of function-call context. */
1425 else
1426 {
1431 {
1435 }
1437 /* Set IDENTIFIER_LOCAL_VALUE (id) to error_mark_node and
1438 add a function-scope shadow entry which will undo that.
1439 This suppresses further warnings about this undeclared
1440 identifier in this function. */
1443 }
1445 }
1446 }
1447 else
1448 {
1449 /* Properly declared variable or function reference. */
1453 {
1457 }
1458 else
1460 }
1470 {
1473 }
1476 }
1478 /* Build a function call to function FUNCTION with parameters PARAMS.
1479 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1480 TREE_VALUE of each node is a parameter-expression.
1481 FUNCTION's data type may be a function type or a pointer-to-function. */
1483 tree
1486 {
1488 tree coerced_params;
1491 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1494 /* Convert anything with function type to a pointer-to-function. */
1496 {
1499 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1500 (because calling an inline function does not mean the function
1501 needs to be separately compiled). */
1507 }
1508 else
1518 {
1521 }
1526 /* fntype now gets the type of function pointed to. */
1529 /* Convert the parameters to the types declared in the
1530 function prototype, or apply default promotions. */
1532 coerced_params
1535 /* Check that the arguments to the function are valid. */
1539 /* Recognize certain built-in functions so we can make tree-codes
1540 other than CALL_EXPR. We do this when it enables fold-const.c
1541 to do something useful. */
1546 {
1551 }
1561 }
1562 \f
1563 /* Convert the argument expressions in the list VALUES
1564 to the types in the list TYPELIST. The result is a list of converted
1565 argument expressions.
1567 If TYPELIST is exhausted, or when an element has NULL as its type,
1568 perform the default conversions.
1570 PARMLIST is the chain of parm decls for the function being called.
1571 It may be 0, if that info is not available.
1572 It is used only for generating error messages.
1574 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1576 This is also where warnings about wrong number of args are generated.
1578 Both VALUES and the returned value are chains of TREE_LIST nodes
1579 with the elements of the list in the TREE_VALUE slots of those nodes. */
1581 static tree
1584 {
1589 /* Scan the given expressions and types, producing individual
1590 converted arguments and pushing them on RESULT in reverse order. */
1593 valtail;
1595 {
1600 {
1604 else
1607 }
1609 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1610 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1611 to convert automatically to a pointer. */
1620 {
1621 /* Formal parm type is specified by a function prototype. */
1622 tree parmval;
1625 {
1628 }
1629 else
1630 {
1631 /* Optionally warn about conversions that
1632 differ from the default conversions. */
1634 {
1639 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1642 warn_for_assignment ("%s as integer rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1645 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1648 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1651 warn_for_assignment ("%s as complex rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1654 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1655 /* ??? At some point, messages should be written about
1656 conversions between complex types, but that's too messy
1657 to do now. */
1660 {
1661 /* Warn if any argument is passed as `float',
1662 since without a prototype it would be `double'. */
1664 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1665 }
1666 /* Detect integer changing in width or signedness.
1667 These warnings are only activated with
1668 -Wconversion, not with -Wtraditional. */
1671 {
1678 /* No warning if function asks for enum
1679 and the actual arg is that enum type. */
1680 ;
1682 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1684 ;
1685 /* Don't complain if the formal parameter type
1686 is an enum, because we can't tell now whether
1687 the value was an enum--even the same enum. */
1689 ;
1692 /* Change in signedness doesn't matter
1693 if a constant value is unaffected. */
1694 ;
1695 /* Likewise for a constant in a NOP_EXPR. */
1699 ;
1704 /* Change in signedness doesn't matter
1705 if an enum value is unaffected. */
1706 ;
1707 #endif
1708 /* If the value is extended from a narrower
1709 unsigned type, it doesn't matter whether we
1710 pass it as signed or unsigned; the value
1711 certainly is the same either way. */
1714 ;
1717 else
1719 }
1720 }
1730 }
1732 }
1736 /* Convert `float' to `double'. */
1738 else
1739 /* Convert `short' and `char' to full-size `int'. */
1744 }
1747 {
1751 else
1753 }
1756 }
1757 \f
1758 /* This is the entry point used by the parser
1759 for binary operators in the input.
1760 In addition to constructing the expression,
1761 we check for operands that were written with other binary operators
1762 in a way that is likely to confuse the user. */
1764 tree
1768 {
1785 /* Check for cases such as x+y<<z which users are likely
1786 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1787 is cleared to prevent these warnings. */
1789 {
1791 {
1795 }
1798 {
1802 }
1805 {
1811 /* Check cases like x|y==z */
1814 }
1817 {
1823 /* Check cases like x^y==z */
1826 }
1829 {
1833 /* Check cases like x&y==z */
1836 }
1837 }
1839 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1850 /* Record the code that was specified in the source,
1851 for the sake of warnings about confusing nesting. */
1854 else
1855 {
1857 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1858 so that convert_for_assignment wouldn't strip it.
1859 That way, we got warnings for things like p = (1 - 1).
1860 But it turns out we should not get those warnings. */
1864 }
1867 }
1869 /* Build a binary-operation expression without default conversions.
1870 CODE is the kind of expression to build.
1871 This function differs from `build' in several ways:
1872 the data type of the result is computed and recorded in it,
1873 warnings are generated if arg data types are invalid,
1874 special handling for addition and subtraction of pointers is known,
1875 and some optimization is done (operations on narrow ints
1876 are done in the narrower type when that gives the same result).
1877 Constant folding is also done before the result is returned.
1879 Note that the operands will never have enumeral types, or function
1880 or array types, because either they will have the default conversions
1881 performed or they have both just been converted to some other type in which
1882 the arithmetic is to be done. */
1884 tree
1889 {
1894 /* Expression code to give to the expression when it is built.
1895 Normally this is CODE, which is what the caller asked for,
1896 but in some special cases we change it. */
1899 /* Data type in which the computation is to be performed.
1900 In the simplest cases this is the common type of the arguments. */
1903 /* Nonzero means operands have already been type-converted
1904 in whatever way is necessary.
1905 Zero means they need to be converted to RESULT_TYPE. */
1908 /* Nonzero means create the expression with this type, rather than
1909 RESULT_TYPE. */
1912 /* Nonzero means after finally constructing the expression
1913 convert it to this type. */
1916 /* Nonzero if this is an operation like MIN or MAX which can
1917 safely be computed in short if both args are promoted shorts.
1918 Also implies COMMON.
1919 -1 indicates a bitwise operation; this makes a difference
1920 in the exact conditions for when it is safe to do the operation
1921 in a narrower mode. */
1924 /* Nonzero if this is a comparison operation;
1925 if both args are promoted shorts, compare the original shorts.
1926 Also implies COMMON. */
1929 /* Nonzero if this is a right-shift operation, which can be computed on the
1930 original short and then promoted if the operand is a promoted short. */
1933 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1937 {
1940 }
1941 else
1942 {
1945 }
1950 /* The expression codes of the data types of the arguments tell us
1951 whether the arguments are integers, floating, pointers, etc. */
1955 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1959 /* If an error was already reported for one of the arguments,
1960 avoid reporting another error. */
1966 {
1968 /* Handle the pointer + int case. */
1973 else
1978 /* Subtraction of two similar pointers.
1979 We must subtract them as integers, then divide by object size. */
1983 /* Handle pointer minus int. Just like pointer plus int. */
1986 else
1999 /* Floating point division by zero is a legitimate way to obtain
2000 infinities and NaNs. */
2008 {
2011 else
2012 /* Although it would be tempting to shorten always here, that
2013 loses on some targets, since the modulo instruction is
2014 undefined if the quotient can't be represented in the
2015 computation mode. We shorten only if unsigned or if
2016 dividing by something we know != -1. */
2021 }
2040 {
2041 /* Although it would be tempting to shorten always here, that loses
2042 on some targets, since the modulo instruction is undefined if the
2043 quotient can't be represented in the computation mode. We shorten
2044 only if unsigned or if dividing by something we know != -1. */
2049 }
2061 {
2062 /* Result of these operations is always an int,
2063 but that does not mean the operands should be
2064 converted to ints! */
2069 }
2072 /* Shift operations: result has same type as first operand;
2073 always convert second operand to int.
2074 Also set SHORT_SHIFT if shifting rightward. */
2078 {
2080 {
2083 else
2084 {
2090 }
2091 }
2093 /* Use the type of the value to be shifted. */
2095 /* Convert the shift-count to an integer, regardless of size
2096 of value being shifted. */
2099 /* Avoid converting op1 to result_type later. */
2101 }
2106 {
2108 {
2114 }
2116 /* Use the type of the value to be shifted. */
2118 /* Convert the shift-count to an integer, regardless of size
2119 of value being shifted. */
2122 /* Avoid converting op1 to result_type later. */
2124 }
2130 {
2132 {
2137 }
2139 /* Use the type of the value to be shifted. */
2141 /* Convert the shift-count to an integer, regardless of size
2142 of value being shifted. */
2145 /* Avoid converting op1 to result_type later. */
2147 }
2154 /* Result of comparison is always int,
2155 but don't convert the args to int! */
2165 {
2168 /* Anything compares with void *. void * compares with anything.
2169 Otherwise, the targets must be compatible
2170 and both must be object or both incomplete. */
2174 {
2175 /* op0 != orig_op0 detects the case of something
2176 whose value is 0 but which isn't a valid null ptr const. */
2180 }
2182 {
2186 }
2187 else
2192 }
2200 {
2203 }
2205 {
2208 }
2217 {
2219 {
2224 }
2225 else
2226 {
2229 }
2230 }
2242 {
2244 {
2252 }
2253 else
2254 {
2257 }
2258 }
2261 {
2265 }
2268 {
2272 }
2274 {
2277 }
2279 {
2282 }
2294 {
2297 }
2303 }
2307 &&
2310 {
2316 /* For certain operations (which identify themselves by shorten != 0)
2317 if both args were extended from the same smaller type,
2318 do the arithmetic in that type and then extend.
2320 shorten !=0 and !=1 indicates a bitwise operation.
2321 For them, this optimization is safe only if
2322 both args are zero-extended or both are sign-extended.
2323 Otherwise, we might change the result.
2324 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2325 but calculated in (unsigned short) it would be (unsigned short)-1. */
2328 {
2332 /* UNS is 1 if the operation to be done is an unsigned one. */
2334 tree type;
2338 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2339 but it *requires* conversion to FINAL_TYPE. */
2350 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2352 /* For bitwise operations, signedness of nominal type
2353 does not matter. Consider only how operands were extended. */
2357 /* Note that in all three cases below we refrain from optimizing
2358 an unsigned operation on sign-extended args.
2359 That would not be valid. */
2361 /* Both args variable: if both extended in same way
2362 from same width, do it in that width.
2363 Do it unsigned if args were zero-extended. */
2370 result_type
2371 = c_common_signed_or_unsigned_type
2377 && (type
2386 && (type
2391 }
2393 /* Shifts can be shortened if shifting right. */
2396 {
2406 /* We can shorten only if the shift count is less than the
2407 number of bits in the smaller type size. */
2409 /* We cannot drop an unsigned shift after sign-extension. */
2411 {
2412 /* Do an unsigned shift if the operand was zero-extended. */
2413 result_type
2416 /* Convert value-to-be-shifted to that type. */
2420 }
2421 }
2423 /* Comparison operations are shortened too but differently.
2424 They identify themselves by setting short_compare = 1. */
2427 {
2428 /* Don't write &op0, etc., because that would prevent op0
2429 from being kept in a register.
2430 Instead, make copies of the our local variables and
2431 pass the copies by reference, then copy them back afterward. */
2434 tree val
2446 {
2458 /* Give warnings for comparisons between signed and unsigned
2459 quantities that may fail.
2461 Do the checking based on the original operand trees, so that
2462 casts will be considered, but default promotions won't be.
2464 Do not warn if the comparison is being done in a signed type,
2465 since the signed type will only be chosen if it can represent
2466 all the values of the unsigned type. */
2469 /* Do not warn if both operands are the same signedness. */
2472 else
2473 {
2478 else
2481 /* Do not warn if the signed quantity is an
2482 unsuffixed integer literal (or some static
2483 constant expression involving such literals or a
2484 conditional expression involving such literals)
2485 and it is non-negative. */
2488 /* Do not warn if the comparison is an equality operation,
2489 the unsigned quantity is an integral constant, and it
2490 would fit in the result if the result were signed. */
2493 && int_fits_type_p
2496 /* Do not warn if the unsigned quantity is an enumeration
2497 constant and its maximum value would fit in the result
2498 if the result were signed. */
2501 && int_fits_type_p
2505 else
2507 }
2509 /* Warn if two unsigned values are being compared in a size
2510 larger than their original size, and one (and only one) is the
2511 result of a `~' operator. This comparison will always fail.
2513 Also warn if one operand is a constant, and the constant
2514 does not have all bits set that are set in the ~ operand
2515 when it is extended. */
2519 {
2523 else
2528 {
2529 tree primop;
2534 {
2538 }
2539 else
2540 {
2544 }
2549 {
2553 }
2554 }
2561 }
2562 }
2563 }
2564 }
2566 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2567 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2568 Then the expression will be built.
2569 It will be given type FINAL_TYPE if that is nonzero;
2570 otherwise, it will be given type RESULT_TYPE. */
2573 {
2576 }
2579 {
2584 }
2589 {
2591 tree folded;
2599 }
2600 }
2601 \f
2603 /* Return true if `t' is known to be non-negative. */
2605 int
2607 tree t;
2608 {
2610 {
2613 /* Find the last statement in the chain, ignoring the final
2614 * scope statement */
2619 }
2621 }
2623 /* Return a tree for the difference of pointers OP0 and OP1.
2624 The resulting tree has type int. */
2626 static tree
2629 {
2638 {
2643 }
2645 /* If the conversion to ptrdiff_type does anything like widening or
2646 converting a partial to an integral mode, we get a convert_expression
2647 that is in the way to do any simplifications.
2648 (fold-const.c doesn't know that the extra bits won't be needed.
2649 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2650 different mode in place.)
2651 So first try to find a common term here 'by hand'; we want to cover
2652 at least the cases that occur in legal static initializers. */
2657 {
2660 }
2661 else
2665 {
2668 }
2669 else
2673 {
2676 }
2679 /* First do the subtraction as integers;
2680 then drop through to build the divide operator.
2681 Do not do default conversions on the minus operator
2682 in case restype is a short type. */
2686 /* This generates an error if op1 is pointer to incomplete type. */
2690 /* This generates an error if op0 is pointer to incomplete type. */
2693 /* Divide by the size, in easiest possible way. */
2701 }
2702 \f
2703 /* Construct and perhaps optimize a tree representation
2704 for a unary operation. CODE, a tree_code, specifies the operation
2705 and XARG is the operand.
2706 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2707 the default promotions (such as from short to int).
2708 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2709 allows non-lvalues; this is only used to handle conversion of non-lvalue
2710 arrays to pointers in C99. */
2712 tree
2715 tree xarg;
2717 {
2718 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2722 tree val;
2731 {
2733 /* This is used for unary plus, because a CONVERT_EXPR
2734 is enough to prevent anybody from looking inside for
2735 associativity, but won't generate any code. */
2738 {
2741 }
2751 {
2754 }
2761 {
2764 }
2766 {
2772 }
2773 else
2774 {
2777 }
2783 {
2786 }
2792 /* Conjugating a real value is a no-op, but allow it anyway. */
2795 {
2798 }
2807 /* These will convert to a pointer. */
2809 {
2812 }
2824 else
2832 else
2839 /* Handle complex lvalues (when permitted)
2840 by reduction to simpler cases. */
2846 /* Increment or decrement the real part of the value,
2847 and don't change the imaginary part. */
2849 {
2860 }
2862 /* Report invalid types. */
2866 {
2869 else
2873 }
2875 {
2876 tree inc;
2882 /* Compute the increment. */
2885 {
2886 /* If pointer target is an undefined struct,
2887 we just cannot know how to do the arithmetic. */
2889 {
2892 else
2894 }
2898 {
2901 else
2903 }
2906 }
2907 else
2912 /* Handle incrementing a cast-expression. */
2916 {
2925 /* If the real type has the same machine representation
2926 as the type it is cast to, we can make better output
2927 by adding directly to the inside of the cast. */
2933 else
2934 {
2938 else
2939 {
2943 else
2952 }
2955 }
2960 }
2961 give_up:
2963 /* Complain about anything else that is not a true lvalue. */
2970 /* Report a read-only lvalue. */
2979 else
2986 }
2989 /* Note that this operation never does default_conversion. */
2991 /* Let &* cancel out to simplify resulting code. */
2993 {
2994 /* Don't let this be an lvalue. */
2998 }
3000 /* For &x[y], return x+y */
3002 {
3007 }
3009 /* Handle complex lvalues (when permitted)
3010 by reduction to simpler cases. */
3016 float f; *&(int)f = 3.4 stores in int format
3017 whereas (int)f = 3.4 stores in float format. */
3018 /* Address of a cast is just a cast of the address
3019 of the operand of the cast. */
3021 {
3034 }
3035 #endif
3037 /* Anything not already handled and not a true memory reference
3038 or a non-lvalue array is an error. */
3043 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3046 /* If the lvalue is const or volatile, merge that into the type
3047 to which the address will point. Note that you can't get a
3048 restricted pointer by taking the address of something, so we
3049 only have to deal with `const' and `volatile' here. */
3061 {
3062 tree addr;
3065 {
3071 {
3075 }
3080 }
3081 else
3084 /* Address of a static or external variable or
3085 file-scope function counts as a constant. */
3091 }
3095 }
3100 }
3102 #if 0
3103 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3104 convert ARG with the same conversions in the same order
3105 and return the result. */
3107 static tree
3109 tree conversions;
3110 tree arg;
3111 {
3113 {
3123 arg));
3127 }
3128 }
3131 /* Return nonzero if REF is an lvalue valid for this language.
3132 Lvalues can be assigned, unless their type has TYPE_READONLY.
3133 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3135 int
3137 tree ref;
3138 {
3142 {
3167 }
3168 }
3170 /* Return nonzero if REF is an lvalue valid for this language;
3171 otherwise, print an error message and return zero. */
3173 int
3175 tree ref;
3177 {
3184 }
3186 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3187 for certain kinds of expressions which are not really lvalues
3188 but which we can accept as lvalues. If FLAG is nonzero, then
3189 non-lvalues are OK since we may be converting a non-lvalue array to
3190 a pointer in C99.
3192 If ARG is not a kind of expression we can handle, return zero. */
3194 static tree
3197 tree arg;
3199 {
3200 /* Handle (a, b) used as an "lvalue". */
3202 {
3205 /* If this returns a function type, it isn't really being used as
3206 an lvalue, so don't issue a warning about it. */
3212 }
3214 /* Handle (a ? b : c) used as an "lvalue". */
3216 {
3226 }
3229 }
3231 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3232 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3234 static void
3237 {
3240 {
3250 }
3251 }
3252 \f
3253 /* Warn about storing in something that is `const'. */
3255 void
3257 tree arg;
3259 {
3261 {
3264 else
3267 }
3271 else
3273 }
3274 \f
3275 /* Mark EXP saying that we need to be able to take the
3276 address of it; it should not be allocated in a register.
3277 Returns true if successful. */
3279 bool
3281 tree exp;
3282 {
3287 {
3290 {
3294 }
3296 /* ... fall through ... */
3316 {
3318 {
3322 }
3325 }
3327 {
3329 {
3333 }
3335 /* If we are making this addressable due to its having
3336 volatile components, give a different error message. Also
3337 handle the case of an unnamed parameter by not trying
3338 to give the name. */
3341 {
3344 }
3348 }
3351 /* drops in */
3357 #endif
3361 }
3362 }
3363 \f
3364 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3366 tree
3369 {
3370 tree type1;
3371 tree type2;
3380 /* Don't promote the operands separately if they promote
3381 the same way. Return the unpromoted type and let the combined
3382 value get promoted if necessary. */
3388 {
3393 }
3394 #endif
3396 /* Promote both alternatives. */
3413 /* Quickly detect the usual case where op1 and op2 have the same type
3414 after promotion. */
3416 {
3419 else
3421 }
3426 {
3429 /* If -Wsign-compare, warn here if type1 and type2 have
3430 different signedness. We'll promote the signed to unsigned
3431 and later code won't know it used to be different.
3432 Do this check on the original types, so that explicit casts
3433 will be considered, but default promotions won't. */
3436 {
3441 {
3442 /* Do not warn if the result type is signed, since the
3443 signed type will only be chosen if it can represent
3444 all the values of the unsigned type. */
3447 /* Do not warn if the signed quantity is an unsuffixed
3448 integer literal (or some static constant expression
3449 involving such literals) and it is non-negative. */
3453 else
3455 }
3456 }
3457 }
3459 {
3463 }
3465 {
3475 {
3480 }
3482 {
3487 }
3488 else
3489 {
3492 }
3493 }
3495 {
3498 else
3499 {
3501 }
3503 }
3505 {
3508 else
3509 {
3511 }
3513 }
3516 {
3519 else
3520 {
3523 }
3524 }
3526 /* Merge const and volatile flags of the incoming types. */
3527 result_type
3541 }
3542 \f
3543 /* Given a list of expressions, return a compound expression
3544 that performs them all and returns the value of the last of them. */
3546 tree
3548 tree list;
3549 {
3551 }
3553 static tree
3555 tree list;
3557 {
3558 tree rest;
3561 {
3562 /* Convert arrays and functions to pointers when there
3563 really is a comma operator. */
3569 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3571 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3574 #endif
3576 /* Don't let (0, 0) be null pointer constant. */
3580 }
3585 {
3586 /* The left-hand operand of a comma expression is like an expression
3587 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3588 any side-effects, unless it was explicitly cast to (void). */
3594 /* When pedantic, a compound expression can be neither an lvalue
3595 nor an integer constant expression. */
3598 }
3600 /* With -Wunused, we should also warn if the left-hand operand does have
3601 side-effects, but computes a value which is not used. For example, in
3602 `foo() + bar(), baz()' the result of the `+' operator is not used,
3603 so we should issue a warning. */
3608 }
3610 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3612 tree
3614 tree type;
3615 tree expr;
3616 {
3622 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3623 only in <protocol> qualifications. But when constructing cast expressions,
3624 the protocols do matter and must be kept around. */
3628 #if 0
3629 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3632 #endif
3635 {
3638 }
3641 {
3644 }
3647 {
3649 {
3653 }
3654 }
3656 {
3657 tree field;
3666 {
3667 tree t;
3675 }
3678 }
3679 else
3680 {
3683 /* If casting to void, avoid the error that would come
3684 from default_conversion in the case of a non-lvalue array. */
3688 /* Convert functions and arrays to pointers,
3689 but don't convert any other types. */
3693 /* Optionally warn about potentially worrisome casts. */
3698 {
3704 /* Check that the qualifiers on IN_TYPE are a superset of
3705 the qualifiers of IN_OTYPE. The outermost level of
3706 POINTER_TYPE nodes is uninteresting and we stop as soon
3707 as we hit a non-POINTER_TYPE node on either type. */
3708 do
3709 {
3713 /* GNU C allows cv-qualified function types. 'const'
3714 means the function is very pure, 'volatile' means it
3715 can't return. We need to warn when such qualifiers
3716 are added, not when they're taken away. */
3720 else
3722 }
3730 /* There are qualifiers present in IN_OTYPE that are not
3731 present in IN_TYPE. */
3733 }
3735 /* Warn about possible alignment problems. */
3741 /* Don't warn about opaque types, where the actual alignment
3742 restriction is unknown. */
3763 /* Don't warn about converting any constant. */
3773 {
3774 /* Casting the address of a decl to non void pointer. Warn
3775 if the cast breaks type based aliasing. */
3782 }
3785 /* Replace a nonvolatile const static variable with its value. */
3790 /* Ignore any integer overflow caused by the cast. */
3792 {
3795 }
3796 }
3798 /* Pedantically, don't let (void *) (FOO *) 0 be a null pointer constant. */
3804 /* If pedantic, don't let a cast be an lvalue. */
3809 }
3811 /* Interpret a cast of expression EXPR to type TYPE. */
3812 tree
3815 {
3818 /* This avoids warnings about unprototyped casts on
3819 integers. E.g. "#define SIG_DFL (void(*)())0". */
3826 }
3828 \f
3829 /* Build an assignment expression of lvalue LHS from value RHS.
3830 MODIFYCODE is the code for a binary operator that we use
3831 to combine the old value of LHS with RHS to get the new value.
3832 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3834 tree
3838 {
3839 tree result;
3840 tree newrhs;
3844 /* Types that aren't fully specified cannot be used in assignments. */
3847 /* Avoid duplicate error messages from operands that had errors. */
3851 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3852 /* Do not use STRIP_NOPS here. We do not want an enumerator
3853 whose value is 0 to count as a null pointer constant. */
3859 /* Handle control structure constructs used as "lvalues". */
3862 {
3863 /* Handle (a, b) used as an "lvalue". */
3872 /* Handle (a ? b : c) used as an "lvalue". */
3876 {
3877 /* Produce (a ? (b = rhs) : (c = rhs))
3878 except that the RHS goes through a save-expr
3879 so the code to compute it is only emitted once. */
3880 tree cond
3888 /* Make sure the code to compute the rhs comes out
3889 before the split. */
3891 /* But cast it to void to avoid an "unused" error. */
3893 }
3896 }
3898 /* If a binary op has been requested, combine the old LHS value with the RHS
3899 producing the value we should actually store into the LHS. */
3902 {
3905 }
3907 /* Handle a cast used as an "lvalue".
3908 We have already performed any binary operator using the value as cast.
3909 Now convert the result to the cast type of the lhs,
3910 and then true type of the lhs and store it there;
3911 then convert result back to the cast type to be the value
3912 of the assignment. */
3915 {
3924 {
3926 tree result;
3934 }
3938 }
3940 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3941 Reject anything strange now. */
3946 /* Warn about storing in something that is `const'. */
3954 /* If storing into a structure or union member,
3955 it has probably been given type `int'.
3956 Compute the type that would go with
3957 the actual amount of storage the member occupies. */
3966 /* If storing in a field that is in actuality a short or narrower than one,
3967 we must store in the field in its actual type. */
3970 {
3973 }
3975 /* Convert new value to destination type. */
3982 /* Scan operands */
3987 /* If we got the LHS in a different type for storing in,
3988 convert the result back to the nominal type of LHS
3989 so that the value we return always has the same type
3990 as the LHS argument. */
3996 }
3997 \f
3998 /* Convert value RHS to type TYPE as preparation for an assignment
3999 to an lvalue of type TYPE.
4000 The real work of conversion is done by `convert'.
4001 The purpose of this function is to generate error messages
4002 for assignments that are not allowed in C.
4003 ERRTYPE is a string to use in error messages:
4004 "assignment", "return", etc. If it is null, this is parameter passing
4005 for a function call (and different error messages are output).
4007 FUNNAME is the name of the function being called,
4008 as an IDENTIFIER_NODE, or null.
4009 PARMNUM is the number of the argument, for printing in error messages. */
4011 static tree
4017 {
4019 tree rhstype;
4022 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4023 /* Do not use STRIP_NOPS here. We do not want an enumerator
4024 whose value is 0 to count as a null pointer constant. */
4041 {
4043 /* Check for Objective-C protocols. This will automatically
4044 issue a warning if there are protocol violations. No need to
4045 use the return value. */
4049 }
4052 {
4055 }
4056 /* A type converts to a reference to it.
4057 This code doesn't fully support references, it's just for the
4058 special case of va_start and va_copy. */
4061 {
4063 {
4066 }
4071 /* We already know that these two types are compatible, but they
4072 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4073 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4074 likely to be va_list, a typedef to __builtin_va_list, which
4075 is different enough that it will cause problems later. */
4081 }
4082 /* Some types can interconvert without explicit casts. */
4087 /* Arithmetic types all interconvert, and enum is treated like int. */
4096 /* Conversion to a transparent union from its member types.
4097 This applies only to function arguments. */
4099 {
4100 tree memb_types;
4105 {
4116 {
4120 /* Any non-function converts to a [const][volatile] void *
4121 and vice versa; otherwise, targets must be the same.
4122 Meanwhile, the lhs target must have all the qualifiers of
4123 the rhs. */
4126 {
4127 /* If this type won't generate any warnings, use it. */
4137 /* Keep looking for a better type, but remember this one. */
4140 }
4141 }
4143 /* Can convert integer zero to any pointer type. */
4147 {
4150 }
4151 }
4154 {
4156 {
4157 /* We have only a marginally acceptable member type;
4158 it needs a warning. */
4162 /* Const and volatile mean something different for function
4163 types, so the usual warnings are not appropriate. */
4166 {
4167 /* Because const and volatile on functions are
4168 restrictions that say the function will not do
4169 certain things, it is okay to use a const or volatile
4170 function where an ordinary one is wanted, but not
4171 vice-versa. */
4175 }
4179 parmnum);
4180 }
4186 }
4187 }
4189 /* Conversions among pointers */
4192 {
4196 /* Any non-function converts to a [const][volatile] void *
4197 and vice versa; otherwise, targets must be the same.
4198 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4203 {
4206 ||
4208 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4209 which are not ANSI null ptr constants. */
4214 /* Const and volatile mean something different for function types,
4215 so the usual warnings are not appropriate. */
4218 {
4222 /* If this is not a case of ignoring a mismatch in signedness,
4223 no warning. */
4226 ;
4227 /* If there is a mismatch, do warn. */
4231 }
4234 {
4235 /* Because const and volatile on functions are restrictions
4236 that say the function will not do certain things,
4237 it is okay to use a const or volatile function
4238 where an ordinary one is wanted, but not vice-versa. */
4242 }
4243 }
4244 else
4248 }
4250 {
4251 /* An explicit constant 0 can convert to a pointer,
4252 or one that results from arithmetic, even including
4253 a cast to integer type. */
4255 &&
4260 {
4264 }
4266 }
4268 {
4272 }
4277 {
4279 {
4285 else
4288 }
4289 else
4291 parmnum);
4292 }
4293 else
4297 }
4299 /* Convert VALUE for assignment into inlined parameter PARM. */
4301 tree
4304 {
4307 /* If FN was prototyped, the value has been converted already
4308 in convert_arguments. */
4321 }
4323 /* Print a warning using MSGID.
4324 It gets OPNAME as its one parameter.
4325 if OPNAME is null and ARGNUM is 0, it is replaced by "passing arg of `FUNCTION'".
4326 Otherwise if OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4327 FUNCTION and ARGNUM are handled specially if we are building an
4328 Objective-C selector. */
4330 static void
4334 tree function;
4336 {
4338 {
4343 {
4346 }
4348 {
4350 {
4351 /* Function name is known; supply it. */
4358 }
4359 else
4360 {
4361 /* Function name unknown (call through ptr). */
4365 }
4366 }
4368 {
4369 /* Function name is known; supply it. */
4376 }
4377 else
4378 {
4379 /* Function name unknown (call through ptr); just give arg number. */
4383 }
4385 }
4387 }
4388 \f
4389 /* If VALUE is a compound expr all of whose expressions are constant, then
4390 return its value. Otherwise, return error_mark_node.
4392 This is for handling COMPOUND_EXPRs as initializer elements
4393 which is allowed with a warning when -pedantic is specified. */
4395 static tree
4397 tree value;
4398 tree endtype;
4399 {
4401 {
4406 endtype);
4407 }
4411 else
4413 }
4414 \f
4415 /* Perform appropriate conversions on the initial value of a variable,
4416 store it in the declaration DECL,
4417 and print any error messages that are appropriate.
4418 If the init is invalid, store an ERROR_MARK. */
4420 void
4423 {
4426 /* If variable's type was invalidly declared, just ignore it. */
4432 /* Digest the specified initializer into an expression. */
4436 /* Store the expression if valid; else report error. */
4438 #if 0
4439 /* Note that this is the only place we can detect the error
4440 in a case such as struct foo bar = (struct foo) { x, y };
4441 where there is one initial value which is a constructor expression. */
4443 ;
4445 {
4448 }
4451 {
4454 }
4455 else
4456 {
4458 {
4463 }
4464 }
4465 #endif
4473 /* ANSI wants warnings about out-of-range constant initializers. */
4477 /* Check if we need to set array size from compound literal size. */
4481 {
4489 {
4493 {
4494 /* For int foo[] = (int [3]){1}; we need to set array size
4495 now since later on array initializer will be just the
4496 brace enclosed list of the compound literal. */
4500 }
4501 }
4502 }
4503 }
4504 \f
4505 /* Methods for storing and printing names for error messages. */
4507 /* Implement a spelling stack that allows components of a name to be pushed
4508 and popped. Each element on the stack is this structure. */
4510 struct spelling
4511 {
4513 union
4514 {
4518 };
4520 #define SPELLING_STRING 1
4521 #define SPELLING_MEMBER 2
4522 #define SPELLING_BOUNDS 3
4528 /* Macros to save and restore the spelling stack around push_... functions.
4529 Alternative to SAVE_SPELLING_STACK. */
4531 #define SPELLING_DEPTH() (spelling - spelling_base)
4532 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4534 /* Push an element on the spelling stack with type KIND and assign VALUE
4535 to MEMBER. */
4537 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4538 { \
4539 int depth = SPELLING_DEPTH (); \
4540 \
4541 if (depth >= spelling_size) \
4542 { \
4543 spelling_size += 10; \
4544 if (spelling_base == 0) \
4545 spelling_base \
4546 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4547 else \
4548 spelling_base \
4549 = (struct spelling *) xrealloc (spelling_base, \
4550 spelling_size * sizeof (struct spelling)); \
4551 RESTORE_SPELLING_DEPTH (depth); \
4552 } \
4553 \
4554 spelling->kind = (KIND); \
4555 spelling->MEMBER = (VALUE); \
4556 spelling++; \
4557 }
4559 /* Push STRING on the stack. Printed literally. */
4561 static void
4564 {
4566 }
4568 /* Push a member name on the stack. Printed as '.' STRING. */
4570 static void
4572 tree decl;
4574 {
4578 }
4580 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4582 static void
4585 {
4587 }
4589 /* Compute the maximum size in bytes of the printed spelling. */
4591 static int
4593 {
4598 {
4601 else
4603 }
4606 }
4608 /* Print the spelling to BUFFER and return it. */
4613 {
4619 {
4622 }
4623 else
4624 {
4629 ;
4630 }
4633 }
4635 /* Issue an error message for a bad initializer component.
4636 MSGID identifies the message.
4637 The component name is taken from the spelling stack. */
4639 void
4642 {
4649 }
4651 /* Issue a pedantic warning for a bad initializer component.
4652 MSGID identifies the message.
4653 The component name is taken from the spelling stack. */
4655 void
4658 {
4665 }
4667 /* Issue a warning for a bad initializer component.
4668 MSGID identifies the message.
4669 The component name is taken from the spelling stack. */
4671 static void
4674 {
4681 }
4682 \f
4683 /* Digest the parser output INIT as an initializer for type TYPE.
4684 Return a C expression of type TYPE to represent the initial value.
4686 REQUIRE_CONSTANT requests an error if non-constant initializers or
4687 elements are seen. */
4689 static tree
4693 {
4702 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4703 /* Do not use STRIP_NOPS here. We do not want an enumerator
4704 whose value is 0 to count as a null pointer constant. */
4710 /* Initialization of an array of chars from a string constant
4711 optionally enclosed in braces. */
4714 {
4722 {
4730 {
4733 }
4737 {
4740 }
4746 /* Subtract 1 (or sizeof (wchar_t))
4747 because it's ok to ignore the terminating null char
4748 that is counted in the length of the constant. */
4759 }
4760 }
4762 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4763 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4764 below and handle as a constructor. */
4770 /* Any type can be initialized
4771 from an expression of the same type, optionally with braces. */
4785 {
4791 {
4792 /* As an extension, allow initializing objects with static storage
4793 duration with compound literals (which are then treated just as
4794 the brace enclosed list they contain). */
4797 }
4801 {
4804 }
4809 /* Compound expressions can only occur here if -pedantic or
4810 -pedantic-errors is specified. In the later case, we always want
4811 an error. In the former case, we simply want a warning. */
4814 {
4815 inside_init
4820 else
4824 }
4827 /* This test catches things like `7 / 0' which
4828 result in an expression for which TREE_CONSTANT
4829 is true, but which is not actually something
4830 that is a legal constant. We really should not
4831 be using this function, because it is a part of
4832 the back-end. Instead, the expression should
4833 already have been turned into ERROR_MARK_NODE. */
4836 {
4839 }
4842 }
4844 /* Handle scalar types, including conversions. */
4848 {
4849 /* Note that convert_for_assignment calls default_conversion
4850 for arrays and functions. We must not call it in the
4851 case where inside_init is a null pointer constant. */
4852 inside_init
4857 {
4860 }
4863 {
4866 }
4869 }
4871 /* Come here only for records and arrays. */
4874 {
4877 }
4881 }
4882 \f
4883 /* Handle initializers that use braces. */
4885 /* Type of object we are accumulating a constructor for.
4886 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4889 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4890 left to fill. */
4893 /* For an ARRAY_TYPE, this is the specified index
4894 at which to store the next element we get. */
4897 /* For an ARRAY_TYPE, this is the maximum index. */
4900 /* For a RECORD_TYPE, this is the first field not yet written out. */
4903 /* For an ARRAY_TYPE, this is the index of the first element
4904 not yet written out. */
4907 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4908 This is so we can generate gaps between fields, when appropriate. */
4911 /* If we are saving up the elements rather than allocating them,
4912 this is the list of elements so far (in reverse order,
4913 most recent first). */
4916 /* 1 if constructor should be incrementally stored into a constructor chain,
4917 0 if all the elements should be kept in AVL tree. */
4920 /* 1 if so far this constructor's elements are all compile-time constants. */
4923 /* 1 if so far this constructor's elements are all valid address constants. */
4926 /* 1 if this constructor is erroneous so far. */
4929 /* 1 if have called defer_addressed_constants. */
4932 /* Structure for managing pending initializer elements, organized as an
4933 AVL tree. */
4935 struct init_node
4936 {
4940 tree purpose;
4941 tree value;
4942 };
4944 /* Tree of pending elements at this constructor level.
4945 These are elements encountered out of order
4946 which belong at places we haven't reached yet in actually
4947 writing the output.
4948 Will never hold tree nodes across GC runs. */
4951 /* The SPELLING_DEPTH of this constructor. */
4954 /* 0 if implicitly pushing constructor levels is allowed. */
4960 /* DECL node for which an initializer is being read.
4961 0 means we are reading a constructor expression
4962 such as (struct foo) {...}. */
4965 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4968 /* Nonzero if this is an initializer for a top-level decl. */
4971 /* Nonzero if there were any member designators in this initializer. */
4974 /* Nesting depth of designator list. */
4977 /* Nonzero if there were diagnosed errors in this designator list. */
4980 \f
4981 /* This stack has a level for each implicit or explicit level of
4982 structuring in the initializer, including the outermost one. It
4983 saves the values of most of the variables above. */
4987 struct constructor_stack
4988 {
4990 tree type;
4991 tree fields;
4992 tree index;
4993 tree max_index;
4994 tree unfilled_index;
4995 tree unfilled_fields;
4996 tree bit_index;
4997 tree elements;
5001 /* If nonzero, this value should replace the entire
5002 constructor at this level. */
5003 tree replacement_value;
5012 };
5016 /* This stack represents designators from some range designator up to
5017 the last designator in the list. */
5019 struct constructor_range_stack
5020 {
5023 tree range_start;
5024 tree index;
5025 tree range_end;
5026 tree fields;
5027 };
5031 /* This stack records separate initializers that are nested.
5032 Nested initializers can't happen in ANSI C, but GNU C allows them
5033 in cases like { ... (struct foo) { ... } ... }. */
5035 struct initializer_stack
5036 {
5038 tree decl;
5042 tree elements;
5050 };
5053 \f
5054 /* Prepare to parse and output the initializer for variable DECL. */
5056 void
5058 tree decl;
5059 tree asmspec_tree;
5061 {
5092 {
5094 require_constant_elements
5096 /* For a scalar, you can always use any value to initialize,
5097 even within braces. */
5103 }
5104 else
5105 {
5109 }
5122 }
5124 void
5126 {
5129 /* Output subconstants (string constants, usually)
5130 that were referenced within this initializer and saved up.
5131 Must do this if and only if we called defer_addressed_constants. */
5135 /* Free the whole constructor stack of this initializer. */
5137 {
5141 }
5146 /* Pop back to the data of the outer initializer (if any). */
5161 }
5162 \f
5163 /* Call here when we see the initializer is surrounded by braces.
5164 This is instead of a call to push_init_level;
5165 it is matched by a call to pop_init_level.
5167 TYPE is the type to initialize, for a constructor expression.
5168 For an initializer for a decl, TYPE is zero. */
5170 void
5172 tree type;
5173 {
5218 {
5220 /* Skip any nameless bit fields at the beginning. */
5227 }
5229 {
5231 {
5232 constructor_max_index
5235 /* Detect non-empty initializations of zero-length arrays. */
5240 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5241 to initialize VLAs will cause a proper error; avoid tree
5242 checking errors as well by setting a safe value. */
5247 constructor_index
5250 }
5251 else
5255 }
5257 {
5258 /* Vectors are like simple fixed-size arrays. */
5259 constructor_max_index =
5263 }
5264 else
5265 {
5266 /* Handle the case of int x = {5}; */
5269 }
5270 }
5271 \f
5272 /* Push down into a subobject, for initialization.
5273 If this is for an explicit set of braces, IMPLICIT is 0.
5274 If it is because the next element belongs at a lower level,
5275 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5277 void
5280 {
5284 /* If we've exhausted any levels that didn't have braces,
5285 pop them now. */
5287 {
5293 && constructor_max_index
5296 else
5298 }
5300 /* Unless this is an explicit brace, we need to preserve previous
5301 content if any. */
5303 {
5310 }
5343 {
5348 }
5350 /* Don't die if an entire brace-pair level is superfluous
5351 in the containing level. */
5353 ;
5356 {
5357 /* Don't die if there are extra init elts at the end. */
5360 else
5361 {
5364 constructor_depth++;
5365 }
5366 }
5368 {
5371 constructor_depth++;
5372 }
5375 {
5380 }
5383 {
5391 }
5394 {
5397 }
5401 {
5403 /* Skip any nameless bit fields at the beginning. */
5410 }
5412 {
5413 /* Vectors are like simple fixed-size arrays. */
5414 constructor_max_index =
5418 }
5420 {
5422 {
5423 constructor_max_index
5426 /* Detect non-empty initializations of zero-length arrays. */
5431 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5432 to initialize VLAs will cause a proper error; avoid tree
5433 checking errors as well by setting a safe value. */
5438 constructor_index
5441 }
5442 else
5447 {
5448 /* We need to split the char/wchar array into individual
5449 characters, so that we don't have to special case it
5450 everywhere. */
5452 }
5453 }
5454 else
5455 {
5459 }
5460 }
5462 /* At the end of an implicit or explicit brace level,
5463 finish up that level of constructor.
5464 If we were outputting the elements as they are read, return 0
5465 from inner levels (process_init_element ignores that),
5466 but return error_mark_node from the outermost level
5467 (that's what we want to put in DECL_INITIAL).
5468 Otherwise, return a CONSTRUCTOR expression. */
5470 tree
5473 {
5478 {
5479 /* When we come to an explicit close brace,
5480 pop any inner levels that didn't have explicit braces. */
5486 }
5490 /* Error for initializing a flexible array member, or a zero-length
5491 array member in an inappropriate context. */
5496 {
5497 /* Silently discard empty initializations. The parser will
5498 already have pedwarned for empty brackets. */
5502 {
5508 /* We have already issued an error message for the existence
5509 of a flexible array member not at the end of the structure.
5510 Discard the initializer so that we do not abort later. */
5513 }
5514 else
5515 /* Zero-length arrays are no longer special, so we should no longer
5516 get here. */
5518 }
5520 /* Warn when some struct elements are implicitly initialized to zero. */
5522 && constructor_type
5525 {
5526 /* Do not warn for flexible array members or zero-length arrays. */
5532 /* Do not warn if this level of the initializer uses member
5533 designators; it is likely to be deliberate. */
5535 {
5539 }
5540 }
5542 /* Now output all pending elements. */
5546 /* Pad out the end of the structure. */
5548 /* If this closes a superfluous brace pair,
5549 just pass out the element between them. */
5552 ;
5557 {
5558 /* A nonincremental scalar initializer--just return
5559 the element, after verifying there is just one. */
5561 {
5565 }
5567 {
5570 }
5571 else
5573 }
5574 else
5575 {
5578 else
5579 {
5586 }
5587 }
5612 {
5616 }
5618 }
5620 /* Common handling for both array range and field name designators.
5621 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5623 static int
5626 {
5627 tree subtype;
5630 /* Don't die if an entire brace-pair level is superfluous
5631 in the containing level. */
5635 /* If there were errors in this designator list already, bail out silently. */
5640 {
5644 /* Designator list starts at the level of closest explicit
5645 braces. */
5650 }
5653 {
5656 }
5660 {
5664 }
5666 {
5668 }
5669 else
5674 {
5677 }
5679 {
5682 }
5687 }
5689 /* If there are range designators in designator list, push a new designator
5690 to constructor_range_stack. RANGE_END is end of such stack range or
5691 NULL_TREE if there is no range designator at this level. */
5693 static void
5695 tree range_end;
5696 {
5711 }
5713 /* Within an array initializer, specify the next index to be initialized.
5714 FIRST is that index. If LAST is nonzero, then initialize a range
5715 of indices, running from FIRST through LAST. */
5717 void
5720 {
5750 else
5751 {
5755 {
5759 {
5762 }
5763 else
5764 {
5768 {
5771 }
5772 }
5773 }
5775 designator_depth++;
5779 }
5780 }
5782 /* Within a struct initializer, specify the next field to be initialized. */
5784 void
5786 tree fieldname;
5787 {
5788 tree tail;
5797 {
5800 }
5804 {
5807 }
5812 else
5813 {
5815 designator_depth++;
5819 }
5820 }
5821 \f
5822 /* Add a new initializer to the tree of pending initializers. PURPOSE
5823 identifies the initializer, either array index or field in a structure.
5824 VALUE is the value of that index or field. */
5826 static void
5829 {
5836 {
5838 {
5844 else
5845 {
5850 }
5851 }
5852 }
5853 else
5854 {
5855 tree bitpos;
5859 {
5865 else
5866 {
5871 }
5872 }
5873 }
5886 {
5890 {
5894 {
5896 {
5897 /* L rotation. */
5910 {
5913 else
5915 }
5916 else
5918 }
5919 else
5920 {
5921 /* LR rotation. */
5943 {
5946 else
5948 }
5949 else
5951 }
5953 }
5954 else
5955 {
5956 /* p->balance == +1; growth of left side balances the node. */
5959 }
5960 }
5962 {
5964 /* Growth propagation from right side. */
5967 {
5969 {
5970 /* R rotation. */
5983 {
5986 else
5988 }
5989 else
5991 }
5993 {
5994 /* RL rotation */
6016 {
6019 else
6021 }
6022 else
6024 }
6026 }
6027 else
6028 {
6029 /* p->balance == -1; growth of right side balances the node. */
6032 }
6033 }
6037 }
6038 }
6040 /* Build AVL tree from a sorted chain. */
6042 static void
6044 {
6045 tree chain;
6055 {
6057 /* Skip any nameless bit fields at the beginning. */
6063 }
6065 {
6067 constructor_unfilled_index
6070 else
6072 }
6074 }
6076 /* Build AVL tree from a string constant. */
6078 static void
6080 tree str;
6081 {
6096 else
6107 {
6109 {
6112 }
6113 else
6114 {
6118 {
6121 else
6126 }
6127 }
6130 {
6133 {
6135 {
6138 }
6139 }
6141 {
6144 }
6149 }
6154 }
6157 }
6159 /* Return value of FIELD in pending initializer or zero if the field was
6160 not initialized yet. */
6162 static tree
6164 tree field;
6165 {
6169 {
6176 {
6181 else
6183 }
6184 }
6186 {
6190 && (!constructor_unfilled_fields
6197 {
6202 else
6204 }
6205 }
6207 {
6211 }
6213 }
6215 /* "Output" the next constructor element.
6216 At top level, really output it to assembler code now.
6217 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6218 TYPE is the data type that the containing data type wants here.
6219 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6221 PENDING if non-nil means output pending elements that belong
6222 right after this element. (PENDING is normally 1;
6223 it is 0 while outputting pending elements, to avoid recursion.) */
6225 static void
6229 {
6241 {
6242 /* As an extension, allow initializing objects with static storage
6243 duration with compound literals (which are then treated just as
6244 the brace enclosed list they contain). */
6247 }
6261 {
6264 }
6269 /* If this field is empty (and not at the end of structure),
6270 don't do anything other than checking the initializer. */
6281 {
6284 }
6286 /* If this element doesn't come next in sequence,
6287 put it on constructor_pending_elts. */
6289 && (!constructor_incremental
6291 {
6298 }
6300 && (!constructor_incremental
6302 {
6303 /* We do this for records but not for unions. In a union,
6304 no matter which field is specified, it can be initialized
6305 right away since it starts at the beginning of the union. */
6307 {
6310 else
6311 {
6319 }
6320 }
6324 }
6327 {
6331 /* We can have just one union field set. */
6333 }
6335 /* Otherwise, output this element either to
6336 constructor_elements or to the assembler file. */
6340 constructor_elements
6343 /* Advance the variable that indicates sequential elements output. */
6345 constructor_unfilled_index
6347 bitsize_one_node);
6349 {
6350 constructor_unfilled_fields
6353 /* Skip any nameless bit fields. */
6357 constructor_unfilled_fields =
6359 }
6363 /* Now output any pending elements which have become next. */
6366 }
6368 /* Output any pending elements which have become next.
6369 As we output elements, constructor_unfilled_{fields,index}
6370 advances, which may cause other elements to become next;
6371 if so, they too are output.
6373 If ALL is 0, we return when there are
6374 no more pending elements to output now.
6376 If ALL is 1, we output space as necessary so that
6377 we can output all the pending elements. */
6379 static void
6382 {
6384 tree next;
6386 retry:
6388 /* Look thru the whole pending tree.
6389 If we find an element that should be output now,
6390 output it. Otherwise, set NEXT to the element
6391 that comes first among those still pending. */
6395 {
6397 {
6399 constructor_unfilled_index))
6405 {
6406 /* Advance to the next smaller node. */
6409 else
6410 {
6411 /* We have reached the smallest node bigger than the
6412 current unfilled index. Fill the space first. */
6415 }
6416 }
6417 else
6418 {
6419 /* Advance to the next bigger node. */
6422 else
6423 {
6424 /* We have reached the biggest node in a subtree. Find
6425 the parent of it, which is the next bigger node. */
6431 {
6434 }
6435 }
6436 }
6437 }
6440 {
6443 /* If the current record is complete we are done. */
6449 /* We can't compare fields here because there might be empty
6450 fields in between. */
6452 {
6456 }
6458 {
6459 /* Advance to the next smaller node. */
6462 else
6463 {
6464 /* We have reached the smallest node bigger than the
6465 current unfilled field. Fill the space first. */
6468 }
6469 }
6470 else
6471 {
6472 /* Advance to the next bigger node. */
6475 else
6476 {
6477 /* We have reached the biggest node in a subtree. Find
6478 the parent of it, which is the next bigger node. */
6485 {
6488 }
6489 }
6490 }
6491 }
6492 }
6494 /* Ordinarily return, but not if we want to output all
6495 and there are elements left. */
6499 /* If it's not incremental, just skip over the gap, so that after
6500 jumping to retry we will output the next successive element. */
6507 /* ELT now points to the node in the pending tree with the next
6508 initializer to output. */
6510 }
6511 \f
6512 /* Add one non-braced element to the current constructor level.
6513 This adjusts the current position within the constructor's type.
6514 This may also start or terminate implicit levels
6515 to handle a partly-braced initializer.
6517 Once this has found the correct level for the new element,
6518 it calls output_init_element. */
6520 void
6522 tree value;
6523 {
6530 /* Handle superfluous braces around string cst as in
6531 char x[] = {"foo"}; */
6533 && constructor_type
6537 {
6542 }
6545 {
6548 }
6550 /* Ignore elements of a brace group if it is entirely superfluous
6551 and has already been diagnosed. */
6555 /* If we've exhausted any levels that didn't have braces,
6556 pop them now. */
6558 {
6566 constructor_index)))
6568 else
6570 }
6572 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6574 {
6575 /* If value is a compound literal and we'll be just using its
6576 content, don't put it into a SAVE_EXPR. */
6578 || !require_constant_value
6581 }
6584 {
6586 {
6587 tree fieldtype;
6591 {
6594 }
6601 /* Error for non-static initialization of a flexible array member. */
6603 && !require_constant_value
6606 {
6609 }
6611 /* Accept a string constant to initialize a subarray. */
6617 /* Otherwise, if we have come to a subaggregate,
6618 and we don't have an element of its type, push into it. */
6624 {
6627 }
6630 {
6634 }
6635 else
6636 /* Do the bookkeeping for an element that was
6637 directly output as a constructor. */
6638 {
6639 /* For a record, keep track of end position of last field. */
6641 constructor_bit_index
6646 /* If the current field was the first one not yet written out,
6647 it isn't now, so update. */
6649 {
6651 /* Skip any nameless bit fields. */
6655 constructor_unfilled_fields =
6657 }
6658 }
6661 /* Skip any nameless bit fields at the beginning. */
6666 }
6668 {
6669 tree fieldtype;
6673 {
6676 }
6683 /* Warn that traditional C rejects initialization of unions.
6684 We skip the warning if the value is zero. This is done
6685 under the assumption that the zero initializer in user
6686 code appears conditioned on e.g. __STDC__ to avoid
6687 "missing initializer" warnings and relies on default
6688 initialization to zero in the traditional C case.
6689 We also skip the warning if the initializer is designated,
6690 again on the assumption that this must be conditional on
6691 __STDC__ anyway (and we've already complained about the
6692 member-designator already). */
6697 /* Accept a string constant to initialize a subarray. */
6703 /* Otherwise, if we have come to a subaggregate,
6704 and we don't have an element of its type, push into it. */
6710 {
6713 }
6716 {
6720 }
6721 else
6722 /* Do the bookkeeping for an element that was
6723 directly output as a constructor. */
6724 {
6727 }
6730 }
6732 {
6736 /* Accept a string constant to initialize a subarray. */
6742 /* Otherwise, if we have come to a subaggregate,
6743 and we don't have an element of its type, push into it. */
6749 {
6752 }
6757 {
6760 }
6762 /* Now output the actual element. */
6764 {
6768 }
6770 constructor_index
6774 /* If we are doing the bookkeeping for an element that was
6775 directly output as a constructor, we must update
6776 constructor_unfilled_index. */
6778 }
6780 {
6783 /* Do a basic check of initializer size. Note that vectors
6784 always have a fixed size derived from their type. */
6786 {
6789 }
6791 /* Now output the actual element. */
6795 constructor_index
6799 /* If we are doing the bookkeeping for an element that was
6800 directly output as a constructor, we must update
6801 constructor_unfilled_index. */
6803 }
6805 /* Handle the sole element allowed in a braced initializer
6806 for a scalar variable. */
6808 {
6811 }
6812 else
6813 {
6817 }
6819 /* Handle range initializers either at this level or anywhere higher
6820 in the designator stack. */
6822 {
6829 {
6833 }
6837 {
6841 }
6848 {
6852 {
6855 }
6863 }
6868 }
6871 }
6874 }
6875 \f
6876 /* Build a simple asm-statement, from one string literal. */
6877 tree
6879 tree expr;
6880 {
6887 {
6888 tree stmt;
6890 /* Simple asm statements are treated as volatile. */
6895 }
6899 }
6901 /* Build an asm-statement, whose components are a CV_QUALIFIER, a
6902 STRING, some OUTPUTS, some INPUTS, and some CLOBBERS. */
6904 tree
6906 tree cv_qualifier;
6907 tree string;
6908 tree outputs;
6909 tree inputs;
6910 tree clobbers;
6911 {
6912 tree tail;
6915 {
6918 }
6922 {
6926 }
6928 /* We can remove output conversions that change the type,
6929 but not the mode. */
6931 {
6937 /* Allow conversions as LHS here. build_modify_expr as called below
6938 will do the right thing with them. */
6949 }
6951 /* Remove output conversions that change the type but not the mode. */
6953 {
6957 }
6959 /* Perform default conversions on array and function inputs.
6960 Don't do this for other types as it would screw up operands
6961 expected to be in memory. */
6967 }
6969 /* Expand an ASM statement with operands, handling output operands
6970 that are not variables or INDIRECT_REFS by transforming such
6971 cases into cases that expand_asm_operands can handle.
6973 Arguments are same as for expand_asm_operands. */
6975 void
6981 {
6984 /* o[I] is the place that output number I should be written. */
6986 tree tail;
6988 /* Record the contents of OUTPUTS before it is modified. */
6990 {
6994 }
6996 /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of
6997 OUTPUTS some trees for where the values were actually stored. */
7000 /* Copy all the intermediate outputs into the specified outputs. */
7002 {
7004 {
7009 /* Restore the original value so that it's correct the next
7010 time we expand this function. */
7012 }
7013 /* Detect modification of read-only values.
7014 (Otherwise done by build_modify_expr.) */
7015 else
7016 {
7024 }
7025 }
7027 /* Those MODIFY_EXPRs could do autoincrements. */
7029 }
7030 \f
7031 /* Expand a C `return' statement.
7032 RETVAL is the expression for what to return,
7033 or a null pointer for `return;' with no value. */
7035 tree
7037 tree retval;
7038 {
7045 {
7050 }
7052 {
7056 }
7057 else
7058 {
7062 tree inner;
7070 /* Strip any conversions, additions, and subtractions, and see if
7071 we are returning the address of a local variable. Warn if so. */
7073 {
7075 {
7082 /* If the second operand of the MINUS_EXPR has a pointer
7083 type (or is converted from it), this may be valid, so
7084 don't give a warning. */
7085 {
7099 }
7116 }
7119 }
7122 }
7125 }
7126 \f
7128 /* The SWITCH_STMT being built. */
7129 tree switch_stmt;
7130 /* A splay-tree mapping the low element of a case range to the high
7131 element, or NULL_TREE if there is no high element. Used to
7132 determine whether or not a new case label duplicates an old case
7133 label. We need a tree, rather than simply a hash table, because
7134 of the GNU case range extension. */
7135 splay_tree cases;
7136 /* The next node on the stack. */
7138 };
7140 /* A stack of the currently active switch statements. The innermost
7141 switch statement is on the top of the stack. There is no need to
7142 mark the stack for garbage collection because it is only active
7143 during the processing of the body of a function, and we never
7144 collect at that point. */
7148 /* Start a C switch statement, testing expression EXP. Return the new
7149 SWITCH_STMT. */
7151 tree
7153 tree exp;
7154 {
7160 {
7166 {
7169 }
7170 else
7171 {
7181 }
7182 }
7184 /* Add this new SWITCH_STMT to the stack. */
7192 }
7194 /* Process a case label. */
7196 tree
7198 tree low_value;
7199 tree high_value;
7200 {
7204 {
7213 {
7214 /* Attach the first case label to the SWITCH_BODY. */
7217 }
7218 }
7221 else
7225 }
7227 /* Finish the switch statement. */
7229 void
7231 {
7234 /* Rechain the next statements to the SWITCH_STMT. */
7237 /* Pop the stack. */
7241 }