| blob | bb696e8cfefd9acce1400348bb12e7fd8663c7c2 |
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 /* Reference to undeclared variable, including reference to
1416 builtin outside of function-call context. */
1420 else
1421 {
1424 {
1429 {
1433 }
1434 }
1437 }
1439 }
1440 }
1441 else
1442 {
1443 /* Properly declared variable or function reference. */
1447 {
1451 }
1452 else
1454 }
1464 {
1467 }
1470 }
1472 /* Build a function call to function FUNCTION with parameters PARAMS.
1473 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1474 TREE_VALUE of each node is a parameter-expression.
1475 FUNCTION's data type may be a function type or a pointer-to-function. */
1477 tree
1480 {
1482 tree coerced_params;
1485 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1488 /* Convert anything with function type to a pointer-to-function. */
1490 {
1493 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1494 (because calling an inline function does not mean the function
1495 needs to be separately compiled). */
1501 }
1502 else
1512 {
1515 }
1520 /* fntype now gets the type of function pointed to. */
1523 /* Convert the parameters to the types declared in the
1524 function prototype, or apply default promotions. */
1526 coerced_params
1529 /* Check that the arguments to the function are valid. */
1533 /* Recognize certain built-in functions so we can make tree-codes
1534 other than CALL_EXPR. We do this when it enables fold-const.c
1535 to do something useful. */
1540 {
1545 }
1555 }
1556 \f
1557 /* Convert the argument expressions in the list VALUES
1558 to the types in the list TYPELIST. The result is a list of converted
1559 argument expressions.
1561 If TYPELIST is exhausted, or when an element has NULL as its type,
1562 perform the default conversions.
1564 PARMLIST is the chain of parm decls for the function being called.
1565 It may be 0, if that info is not available.
1566 It is used only for generating error messages.
1568 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1570 This is also where warnings about wrong number of args are generated.
1572 Both VALUES and the returned value are chains of TREE_LIST nodes
1573 with the elements of the list in the TREE_VALUE slots of those nodes. */
1575 static tree
1578 {
1583 /* Scan the given expressions and types, producing individual
1584 converted arguments and pushing them on RESULT in reverse order. */
1587 valtail;
1589 {
1594 {
1598 else
1601 }
1603 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1604 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1605 to convert automatically to a pointer. */
1614 {
1615 /* Formal parm type is specified by a function prototype. */
1616 tree parmval;
1619 {
1622 }
1623 else
1624 {
1625 /* Optionally warn about conversions that
1626 differ from the default conversions. */
1628 {
1633 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1636 warn_for_assignment ("%s as integer rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1639 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1642 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1645 warn_for_assignment ("%s as complex rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1648 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1649 /* ??? At some point, messages should be written about
1650 conversions between complex types, but that's too messy
1651 to do now. */
1654 {
1655 /* Warn if any argument is passed as `float',
1656 since without a prototype it would be `double'. */
1658 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1659 }
1660 /* Detect integer changing in width or signedness.
1661 These warnings are only activated with
1662 -Wconversion, not with -Wtraditional. */
1665 {
1672 /* No warning if function asks for enum
1673 and the actual arg is that enum type. */
1674 ;
1676 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1678 ;
1679 /* Don't complain if the formal parameter type
1680 is an enum, because we can't tell now whether
1681 the value was an enum--even the same enum. */
1683 ;
1686 /* Change in signedness doesn't matter
1687 if a constant value is unaffected. */
1688 ;
1689 /* Likewise for a constant in a NOP_EXPR. */
1693 ;
1698 /* Change in signedness doesn't matter
1699 if an enum value is unaffected. */
1700 ;
1701 #endif
1702 /* If the value is extended from a narrower
1703 unsigned type, it doesn't matter whether we
1704 pass it as signed or unsigned; the value
1705 certainly is the same either way. */
1708 ;
1711 else
1713 }
1714 }
1724 }
1726 }
1730 /* Convert `float' to `double'. */
1732 else
1733 /* Convert `short' and `char' to full-size `int'. */
1738 }
1741 {
1745 else
1747 }
1750 }
1751 \f
1752 /* This is the entry point used by the parser
1753 for binary operators in the input.
1754 In addition to constructing the expression,
1755 we check for operands that were written with other binary operators
1756 in a way that is likely to confuse the user. */
1758 tree
1762 {
1779 /* Check for cases such as x+y<<z which users are likely
1780 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1781 is cleared to prevent these warnings. */
1783 {
1785 {
1789 }
1792 {
1796 }
1799 {
1805 /* Check cases like x|y==z */
1808 }
1811 {
1817 /* Check cases like x^y==z */
1820 }
1823 {
1827 /* Check cases like x&y==z */
1830 }
1831 }
1833 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1844 /* Record the code that was specified in the source,
1845 for the sake of warnings about confusing nesting. */
1848 else
1849 {
1851 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1852 so that convert_for_assignment wouldn't strip it.
1853 That way, we got warnings for things like p = (1 - 1).
1854 But it turns out we should not get those warnings. */
1858 }
1861 }
1863 /* Build a binary-operation expression without default conversions.
1864 CODE is the kind of expression to build.
1865 This function differs from `build' in several ways:
1866 the data type of the result is computed and recorded in it,
1867 warnings are generated if arg data types are invalid,
1868 special handling for addition and subtraction of pointers is known,
1869 and some optimization is done (operations on narrow ints
1870 are done in the narrower type when that gives the same result).
1871 Constant folding is also done before the result is returned.
1873 Note that the operands will never have enumeral types, or function
1874 or array types, because either they will have the default conversions
1875 performed or they have both just been converted to some other type in which
1876 the arithmetic is to be done. */
1878 tree
1883 {
1888 /* Expression code to give to the expression when it is built.
1889 Normally this is CODE, which is what the caller asked for,
1890 but in some special cases we change it. */
1893 /* Data type in which the computation is to be performed.
1894 In the simplest cases this is the common type of the arguments. */
1897 /* Nonzero means operands have already been type-converted
1898 in whatever way is necessary.
1899 Zero means they need to be converted to RESULT_TYPE. */
1902 /* Nonzero means create the expression with this type, rather than
1903 RESULT_TYPE. */
1906 /* Nonzero means after finally constructing the expression
1907 convert it to this type. */
1910 /* Nonzero if this is an operation like MIN or MAX which can
1911 safely be computed in short if both args are promoted shorts.
1912 Also implies COMMON.
1913 -1 indicates a bitwise operation; this makes a difference
1914 in the exact conditions for when it is safe to do the operation
1915 in a narrower mode. */
1918 /* Nonzero if this is a comparison operation;
1919 if both args are promoted shorts, compare the original shorts.
1920 Also implies COMMON. */
1923 /* Nonzero if this is a right-shift operation, which can be computed on the
1924 original short and then promoted if the operand is a promoted short. */
1927 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1931 {
1934 }
1935 else
1936 {
1939 }
1944 /* The expression codes of the data types of the arguments tell us
1945 whether the arguments are integers, floating, pointers, etc. */
1949 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1953 /* If an error was already reported for one of the arguments,
1954 avoid reporting another error. */
1960 {
1962 /* Handle the pointer + int case. */
1967 else
1972 /* Subtraction of two similar pointers.
1973 We must subtract them as integers, then divide by object size. */
1977 /* Handle pointer minus int. Just like pointer plus int. */
1980 else
1993 /* Floating point division by zero is a legitimate way to obtain
1994 infinities and NaNs. */
2002 {
2005 else
2006 /* Although it would be tempting to shorten always here, that
2007 loses on some targets, since the modulo instruction is
2008 undefined if the quotient can't be represented in the
2009 computation mode. We shorten only if unsigned or if
2010 dividing by something we know != -1. */
2015 }
2034 {
2035 /* Although it would be tempting to shorten always here, that loses
2036 on some targets, since the modulo instruction is undefined if the
2037 quotient can't be represented in the computation mode. We shorten
2038 only if unsigned or if dividing by something we know != -1. */
2043 }
2055 {
2056 /* Result of these operations is always an int,
2057 but that does not mean the operands should be
2058 converted to ints! */
2063 }
2066 /* Shift operations: result has same type as first operand;
2067 always convert second operand to int.
2068 Also set SHORT_SHIFT if shifting rightward. */
2072 {
2074 {
2077 else
2078 {
2084 }
2085 }
2087 /* Use the type of the value to be shifted. */
2089 /* Convert the shift-count to an integer, regardless of size
2090 of value being shifted. */
2093 /* Avoid converting op1 to result_type later. */
2095 }
2100 {
2102 {
2108 }
2110 /* Use the type of the value to be shifted. */
2112 /* Convert the shift-count to an integer, regardless of size
2113 of value being shifted. */
2116 /* Avoid converting op1 to result_type later. */
2118 }
2124 {
2126 {
2131 }
2133 /* Use the type of the value to be shifted. */
2135 /* Convert the shift-count to an integer, regardless of size
2136 of value being shifted. */
2139 /* Avoid converting op1 to result_type later. */
2141 }
2148 /* Result of comparison is always int,
2149 but don't convert the args to int! */
2159 {
2162 /* Anything compares with void *. void * compares with anything.
2163 Otherwise, the targets must be compatible
2164 and both must be object or both incomplete. */
2168 {
2169 /* op0 != orig_op0 detects the case of something
2170 whose value is 0 but which isn't a valid null ptr const. */
2174 }
2176 {
2180 }
2181 else
2186 }
2194 {
2197 }
2199 {
2202 }
2211 {
2213 {
2218 }
2219 else
2220 {
2223 }
2224 }
2236 {
2238 {
2246 }
2247 else
2248 {
2251 }
2252 }
2255 {
2259 }
2262 {
2266 }
2268 {
2271 }
2273 {
2276 }
2288 {
2291 }
2297 }
2301 &&
2304 {
2310 /* For certain operations (which identify themselves by shorten != 0)
2311 if both args were extended from the same smaller type,
2312 do the arithmetic in that type and then extend.
2314 shorten !=0 and !=1 indicates a bitwise operation.
2315 For them, this optimization is safe only if
2316 both args are zero-extended or both are sign-extended.
2317 Otherwise, we might change the result.
2318 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2319 but calculated in (unsigned short) it would be (unsigned short)-1. */
2322 {
2326 /* UNS is 1 if the operation to be done is an unsigned one. */
2328 tree type;
2332 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2333 but it *requires* conversion to FINAL_TYPE. */
2344 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2346 /* For bitwise operations, signedness of nominal type
2347 does not matter. Consider only how operands were extended. */
2351 /* Note that in all three cases below we refrain from optimizing
2352 an unsigned operation on sign-extended args.
2353 That would not be valid. */
2355 /* Both args variable: if both extended in same way
2356 from same width, do it in that width.
2357 Do it unsigned if args were zero-extended. */
2364 result_type
2365 = c_common_signed_or_unsigned_type
2371 && (type
2380 && (type
2385 }
2387 /* Shifts can be shortened if shifting right. */
2390 {
2400 /* We can shorten only if the shift count is less than the
2401 number of bits in the smaller type size. */
2403 /* We cannot drop an unsigned shift after sign-extension. */
2405 {
2406 /* Do an unsigned shift if the operand was zero-extended. */
2407 result_type
2410 /* Convert value-to-be-shifted to that type. */
2414 }
2415 }
2417 /* Comparison operations are shortened too but differently.
2418 They identify themselves by setting short_compare = 1. */
2421 {
2422 /* Don't write &op0, etc., because that would prevent op0
2423 from being kept in a register.
2424 Instead, make copies of the our local variables and
2425 pass the copies by reference, then copy them back afterward. */
2428 tree val
2440 {
2452 /* Give warnings for comparisons between signed and unsigned
2453 quantities that may fail.
2455 Do the checking based on the original operand trees, so that
2456 casts will be considered, but default promotions won't be.
2458 Do not warn if the comparison is being done in a signed type,
2459 since the signed type will only be chosen if it can represent
2460 all the values of the unsigned type. */
2463 /* Do not warn if both operands are the same signedness. */
2466 else
2467 {
2472 else
2475 /* Do not warn if the signed quantity is an
2476 unsuffixed integer literal (or some static
2477 constant expression involving such literals or a
2478 conditional expression involving such literals)
2479 and it is non-negative. */
2482 /* Do not warn if the comparison is an equality operation,
2483 the unsigned quantity is an integral constant, and it
2484 would fit in the result if the result were signed. */
2487 && int_fits_type_p
2490 /* Do not warn if the unsigned quantity is an enumeration
2491 constant and its maximum value would fit in the result
2492 if the result were signed. */
2495 && int_fits_type_p
2499 else
2501 }
2503 /* Warn if two unsigned values are being compared in a size
2504 larger than their original size, and one (and only one) is the
2505 result of a `~' operator. This comparison will always fail.
2507 Also warn if one operand is a constant, and the constant
2508 does not have all bits set that are set in the ~ operand
2509 when it is extended. */
2513 {
2517 else
2522 {
2523 tree primop;
2528 {
2532 }
2533 else
2534 {
2538 }
2543 {
2547 }
2548 }
2555 }
2556 }
2557 }
2558 }
2560 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2561 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2562 Then the expression will be built.
2563 It will be given type FINAL_TYPE if that is nonzero;
2564 otherwise, it will be given type RESULT_TYPE. */
2567 {
2570 }
2573 {
2578 }
2583 {
2585 tree folded;
2593 }
2594 }
2595 \f
2597 /* Return true if `t' is known to be non-negative. */
2599 int
2601 tree t;
2602 {
2604 {
2607 /* Find the last statement in the chain, ignoring the final
2608 * scope statement */
2613 }
2615 }
2617 /* Return a tree for the difference of pointers OP0 and OP1.
2618 The resulting tree has type int. */
2620 static tree
2623 {
2632 {
2637 }
2639 /* If the conversion to ptrdiff_type does anything like widening or
2640 converting a partial to an integral mode, we get a convert_expression
2641 that is in the way to do any simplifications.
2642 (fold-const.c doesn't know that the extra bits won't be needed.
2643 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2644 different mode in place.)
2645 So first try to find a common term here 'by hand'; we want to cover
2646 at least the cases that occur in legal static initializers. */
2651 {
2654 }
2655 else
2659 {
2662 }
2663 else
2667 {
2670 }
2673 /* First do the subtraction as integers;
2674 then drop through to build the divide operator.
2675 Do not do default conversions on the minus operator
2676 in case restype is a short type. */
2680 /* This generates an error if op1 is pointer to incomplete type. */
2684 /* This generates an error if op0 is pointer to incomplete type. */
2687 /* Divide by the size, in easiest possible way. */
2695 }
2696 \f
2697 /* Construct and perhaps optimize a tree representation
2698 for a unary operation. CODE, a tree_code, specifies the operation
2699 and XARG is the operand.
2700 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2701 the default promotions (such as from short to int).
2702 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2703 allows non-lvalues; this is only used to handle conversion of non-lvalue
2704 arrays to pointers in C99. */
2706 tree
2709 tree xarg;
2711 {
2712 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2716 tree val;
2725 {
2727 /* This is used for unary plus, because a CONVERT_EXPR
2728 is enough to prevent anybody from looking inside for
2729 associativity, but won't generate any code. */
2732 {
2735 }
2745 {
2748 }
2755 {
2758 }
2760 {
2766 }
2767 else
2768 {
2771 }
2777 {
2780 }
2786 /* Conjugating a real value is a no-op, but allow it anyway. */
2789 {
2792 }
2801 /* These will convert to a pointer. */
2803 {
2806 }
2818 else
2826 else
2833 /* Handle complex lvalues (when permitted)
2834 by reduction to simpler cases. */
2840 /* Increment or decrement the real part of the value,
2841 and don't change the imaginary part. */
2843 {
2854 }
2856 /* Report invalid types. */
2860 {
2863 else
2867 }
2869 {
2870 tree inc;
2876 /* Compute the increment. */
2879 {
2880 /* If pointer target is an undefined struct,
2881 we just cannot know how to do the arithmetic. */
2883 {
2886 else
2888 }
2892 {
2895 else
2897 }
2900 }
2901 else
2906 /* Handle incrementing a cast-expression. */
2910 {
2919 /* If the real type has the same machine representation
2920 as the type it is cast to, we can make better output
2921 by adding directly to the inside of the cast. */
2927 else
2928 {
2932 else
2933 {
2937 else
2946 }
2949 }
2954 }
2955 give_up:
2957 /* Complain about anything else that is not a true lvalue. */
2964 /* Report a read-only lvalue. */
2973 else
2980 }
2983 /* Note that this operation never does default_conversion. */
2985 /* Let &* cancel out to simplify resulting code. */
2987 {
2988 /* Don't let this be an lvalue. */
2992 }
2994 /* For &x[y], return x+y */
2996 {
3001 }
3003 /* Handle complex lvalues (when permitted)
3004 by reduction to simpler cases. */
3010 float f; *&(int)f = 3.4 stores in int format
3011 whereas (int)f = 3.4 stores in float format. */
3012 /* Address of a cast is just a cast of the address
3013 of the operand of the cast. */
3015 {
3028 }
3029 #endif
3031 /* Anything not already handled and not a true memory reference
3032 or a non-lvalue array is an error. */
3037 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3040 /* If the lvalue is const or volatile, merge that into the type
3041 to which the address will point. Note that you can't get a
3042 restricted pointer by taking the address of something, so we
3043 only have to deal with `const' and `volatile' here. */
3055 {
3056 tree addr;
3059 {
3065 {
3069 }
3074 }
3075 else
3078 /* Address of a static or external variable or
3079 file-scope function counts as a constant. */
3085 }
3089 }
3094 }
3096 #if 0
3097 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3098 convert ARG with the same conversions in the same order
3099 and return the result. */
3101 static tree
3103 tree conversions;
3104 tree arg;
3105 {
3107 {
3117 arg));
3121 }
3122 }
3125 /* Return nonzero if REF is an lvalue valid for this language.
3126 Lvalues can be assigned, unless their type has TYPE_READONLY.
3127 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3129 int
3131 tree ref;
3132 {
3136 {
3161 }
3162 }
3164 /* Return nonzero if REF is an lvalue valid for this language;
3165 otherwise, print an error message and return zero. */
3167 int
3169 tree ref;
3171 {
3178 }
3180 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3181 for certain kinds of expressions which are not really lvalues
3182 but which we can accept as lvalues. If FLAG is nonzero, then
3183 non-lvalues are OK since we may be converting a non-lvalue array to
3184 a pointer in C99.
3186 If ARG is not a kind of expression we can handle, return zero. */
3188 static tree
3191 tree arg;
3193 {
3194 /* Handle (a, b) used as an "lvalue". */
3196 {
3199 /* If this returns a function type, it isn't really being used as
3200 an lvalue, so don't issue a warning about it. */
3206 }
3208 /* Handle (a ? b : c) used as an "lvalue". */
3210 {
3220 }
3223 }
3225 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3226 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3228 static void
3231 {
3234 {
3244 }
3245 }
3246 \f
3247 /* Warn about storing in something that is `const'. */
3249 void
3251 tree arg;
3253 {
3255 {
3258 else
3261 }
3265 else
3267 }
3268 \f
3269 /* Mark EXP saying that we need to be able to take the
3270 address of it; it should not be allocated in a register.
3271 Returns true if successful. */
3273 bool
3275 tree exp;
3276 {
3281 {
3284 {
3288 }
3290 /* ... fall through ... */
3310 {
3312 {
3316 }
3319 }
3321 {
3323 {
3327 }
3329 /* If we are making this addressable due to its having
3330 volatile components, give a different error message. Also
3331 handle the case of an unnamed parameter by not trying
3332 to give the name. */
3335 {
3338 }
3342 }
3345 /* drops in */
3351 #endif
3355 }
3356 }
3357 \f
3358 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3360 tree
3363 {
3364 tree type1;
3365 tree type2;
3374 /* Don't promote the operands separately if they promote
3375 the same way. Return the unpromoted type and let the combined
3376 value get promoted if necessary. */
3382 {
3387 }
3388 #endif
3390 /* Promote both alternatives. */
3407 /* Quickly detect the usual case where op1 and op2 have the same type
3408 after promotion. */
3410 {
3413 else
3415 }
3420 {
3423 /* If -Wsign-compare, warn here if type1 and type2 have
3424 different signedness. We'll promote the signed to unsigned
3425 and later code won't know it used to be different.
3426 Do this check on the original types, so that explicit casts
3427 will be considered, but default promotions won't. */
3430 {
3435 {
3436 /* Do not warn if the result type is signed, since the
3437 signed type will only be chosen if it can represent
3438 all the values of the unsigned type. */
3441 /* Do not warn if the signed quantity is an unsuffixed
3442 integer literal (or some static constant expression
3443 involving such literals) and it is non-negative. */
3447 else
3449 }
3450 }
3451 }
3453 {
3457 }
3459 {
3469 {
3474 }
3476 {
3481 }
3482 else
3483 {
3486 }
3487 }
3489 {
3492 else
3493 {
3495 }
3497 }
3499 {
3502 else
3503 {
3505 }
3507 }
3510 {
3513 else
3514 {
3517 }
3518 }
3520 /* Merge const and volatile flags of the incoming types. */
3521 result_type
3535 }
3536 \f
3537 /* Given a list of expressions, return a compound expression
3538 that performs them all and returns the value of the last of them. */
3540 tree
3542 tree list;
3543 {
3545 }
3547 static tree
3549 tree list;
3551 {
3552 tree rest;
3555 {
3556 /* Convert arrays and functions to pointers when there
3557 really is a comma operator. */
3563 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3565 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3568 #endif
3570 /* Don't let (0, 0) be null pointer constant. */
3574 }
3579 {
3580 /* The left-hand operand of a comma expression is like an expression
3581 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3582 any side-effects, unless it was explicitly cast to (void). */
3588 /* When pedantic, a compound expression can be neither an lvalue
3589 nor an integer constant expression. */
3592 }
3594 /* With -Wunused, we should also warn if the left-hand operand does have
3595 side-effects, but computes a value which is not used. For example, in
3596 `foo() + bar(), baz()' the result of the `+' operator is not used,
3597 so we should issue a warning. */
3602 }
3604 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3606 tree
3608 tree type;
3609 tree expr;
3610 {
3616 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3617 only in <protocol> qualifications. But when constructing cast expressions,
3618 the protocols do matter and must be kept around. */
3622 #if 0
3623 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3626 #endif
3629 {
3632 }
3635 {
3638 }
3641 {
3643 {
3647 }
3648 }
3650 {
3651 tree field;
3660 {
3661 tree t;
3669 }
3672 }
3673 else
3674 {
3677 /* If casting to void, avoid the error that would come
3678 from default_conversion in the case of a non-lvalue array. */
3682 /* Convert functions and arrays to pointers,
3683 but don't convert any other types. */
3687 /* Optionally warn about potentially worrisome casts. */
3692 {
3698 /* Check that the qualifiers on IN_TYPE are a superset of
3699 the qualifiers of IN_OTYPE. The outermost level of
3700 POINTER_TYPE nodes is uninteresting and we stop as soon
3701 as we hit a non-POINTER_TYPE node on either type. */
3702 do
3703 {
3707 /* GNU C allows cv-qualified function types. 'const'
3708 means the function is very pure, 'volatile' means it
3709 can't return. We need to warn when such qualifiers
3710 are added, not when they're taken away. */
3714 else
3716 }
3724 /* There are qualifiers present in IN_OTYPE that are not
3725 present in IN_TYPE. */
3727 }
3729 /* Warn about possible alignment problems. */
3735 /* Don't warn about opaque types, where the actual alignment
3736 restriction is unknown. */
3757 /* Don't warn about converting any constant. */
3767 {
3768 /* Casting the address of a decl to non void pointer. Warn
3769 if the cast breaks type based aliasing. */
3776 }
3779 /* Replace a nonvolatile const static variable with its value. */
3784 /* Ignore any integer overflow caused by the cast. */
3786 {
3789 }
3790 }
3792 /* Pedantically, don't let (void *) (FOO *) 0 be a null pointer constant. */
3798 /* If pedantic, don't let a cast be an lvalue. */
3803 }
3805 /* Interpret a cast of expression EXPR to type TYPE. */
3806 tree
3809 {
3812 /* This avoids warnings about unprototyped casts on
3813 integers. E.g. "#define SIG_DFL (void(*)())0". */
3820 }
3822 \f
3823 /* Build an assignment expression of lvalue LHS from value RHS.
3824 MODIFYCODE is the code for a binary operator that we use
3825 to combine the old value of LHS with RHS to get the new value.
3826 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3828 tree
3832 {
3833 tree result;
3834 tree newrhs;
3838 /* Types that aren't fully specified cannot be used in assignments. */
3841 /* Avoid duplicate error messages from operands that had errors. */
3845 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3846 /* Do not use STRIP_NOPS here. We do not want an enumerator
3847 whose value is 0 to count as a null pointer constant. */
3853 /* Handle control structure constructs used as "lvalues". */
3856 {
3857 /* Handle (a, b) used as an "lvalue". */
3866 /* Handle (a ? b : c) used as an "lvalue". */
3870 {
3871 /* Produce (a ? (b = rhs) : (c = rhs))
3872 except that the RHS goes through a save-expr
3873 so the code to compute it is only emitted once. */
3874 tree cond
3882 /* Make sure the code to compute the rhs comes out
3883 before the split. */
3885 /* But cast it to void to avoid an "unused" error. */
3887 }
3890 }
3892 /* If a binary op has been requested, combine the old LHS value with the RHS
3893 producing the value we should actually store into the LHS. */
3896 {
3899 }
3901 /* Handle a cast used as an "lvalue".
3902 We have already performed any binary operator using the value as cast.
3903 Now convert the result to the cast type of the lhs,
3904 and then true type of the lhs and store it there;
3905 then convert result back to the cast type to be the value
3906 of the assignment. */
3909 {
3918 {
3920 tree result;
3928 }
3932 }
3934 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3935 Reject anything strange now. */
3940 /* Warn about storing in something that is `const'. */
3948 /* If storing into a structure or union member,
3949 it has probably been given type `int'.
3950 Compute the type that would go with
3951 the actual amount of storage the member occupies. */
3960 /* If storing in a field that is in actuality a short or narrower than one,
3961 we must store in the field in its actual type. */
3964 {
3967 }
3969 /* Convert new value to destination type. */
3976 /* Scan operands */
3981 /* If we got the LHS in a different type for storing in,
3982 convert the result back to the nominal type of LHS
3983 so that the value we return always has the same type
3984 as the LHS argument. */
3990 }
3991 \f
3992 /* Convert value RHS to type TYPE as preparation for an assignment
3993 to an lvalue of type TYPE.
3994 The real work of conversion is done by `convert'.
3995 The purpose of this function is to generate error messages
3996 for assignments that are not allowed in C.
3997 ERRTYPE is a string to use in error messages:
3998 "assignment", "return", etc. If it is null, this is parameter passing
3999 for a function call (and different error messages are output).
4001 FUNNAME is the name of the function being called,
4002 as an IDENTIFIER_NODE, or null.
4003 PARMNUM is the number of the argument, for printing in error messages. */
4005 static tree
4011 {
4013 tree rhstype;
4016 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4017 /* Do not use STRIP_NOPS here. We do not want an enumerator
4018 whose value is 0 to count as a null pointer constant. */
4035 {
4037 /* Check for Objective-C protocols. This will automatically
4038 issue a warning if there are protocol violations. No need to
4039 use the return value. */
4043 }
4046 {
4049 }
4050 /* A type converts to a reference to it.
4051 This code doesn't fully support references, it's just for the
4052 special case of va_start and va_copy. */
4055 {
4057 {
4060 }
4065 /* We already know that these two types are compatible, but they
4066 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4067 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4068 likely to be va_list, a typedef to __builtin_va_list, which
4069 is different enough that it will cause problems later. */
4075 }
4076 /* Some types can interconvert without explicit casts. */
4081 /* Arithmetic types all interconvert, and enum is treated like int. */
4090 /* Conversion to a transparent union from its member types.
4091 This applies only to function arguments. */
4093 {
4094 tree memb_types;
4099 {
4110 {
4114 /* Any non-function converts to a [const][volatile] void *
4115 and vice versa; otherwise, targets must be the same.
4116 Meanwhile, the lhs target must have all the qualifiers of
4117 the rhs. */
4120 {
4121 /* If this type won't generate any warnings, use it. */
4131 /* Keep looking for a better type, but remember this one. */
4134 }
4135 }
4137 /* Can convert integer zero to any pointer type. */
4141 {
4144 }
4145 }
4148 {
4150 {
4151 /* We have only a marginally acceptable member type;
4152 it needs a warning. */
4156 /* Const and volatile mean something different for function
4157 types, so the usual warnings are not appropriate. */
4160 {
4161 /* Because const and volatile on functions are
4162 restrictions that say the function will not do
4163 certain things, it is okay to use a const or volatile
4164 function where an ordinary one is wanted, but not
4165 vice-versa. */
4169 }
4173 parmnum);
4174 }
4180 }
4181 }
4183 /* Conversions among pointers */
4186 {
4190 /* Any non-function converts to a [const][volatile] void *
4191 and vice versa; otherwise, targets must be the same.
4192 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4197 {
4200 ||
4202 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4203 which are not ANSI null ptr constants. */
4208 /* Const and volatile mean something different for function types,
4209 so the usual warnings are not appropriate. */
4212 {
4216 /* If this is not a case of ignoring a mismatch in signedness,
4217 no warning. */
4220 ;
4221 /* If there is a mismatch, do warn. */
4225 }
4228 {
4229 /* Because const and volatile on functions are restrictions
4230 that say the function will not do certain things,
4231 it is okay to use a const or volatile function
4232 where an ordinary one is wanted, but not vice-versa. */
4236 }
4237 }
4238 else
4242 }
4244 {
4245 /* An explicit constant 0 can convert to a pointer,
4246 or one that results from arithmetic, even including
4247 a cast to integer type. */
4249 &&
4254 {
4258 }
4260 }
4262 {
4266 }
4271 {
4273 {
4279 else
4282 }
4283 else
4285 parmnum);
4286 }
4287 else
4291 }
4293 /* Convert VALUE for assignment into inlined parameter PARM. */
4295 tree
4298 {
4301 /* If FN was prototyped, the value has been converted already
4302 in convert_arguments. */
4315 }
4317 /* Print a warning using MSGID.
4318 It gets OPNAME as its one parameter.
4319 if OPNAME is null and ARGNUM is 0, it is replaced by "passing arg of `FUNCTION'".
4320 Otherwise if OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4321 FUNCTION and ARGNUM are handled specially if we are building an
4322 Objective-C selector. */
4324 static void
4328 tree function;
4330 {
4332 {
4337 {
4340 }
4342 {
4344 {
4345 /* Function name is known; supply it. */
4352 }
4353 else
4354 {
4355 /* Function name unknown (call through ptr). */
4359 }
4360 }
4362 {
4363 /* Function name is known; supply it. */
4370 }
4371 else
4372 {
4373 /* Function name unknown (call through ptr); just give arg number. */
4377 }
4379 }
4381 }
4382 \f
4383 /* If VALUE is a compound expr all of whose expressions are constant, then
4384 return its value. Otherwise, return error_mark_node.
4386 This is for handling COMPOUND_EXPRs as initializer elements
4387 which is allowed with a warning when -pedantic is specified. */
4389 static tree
4391 tree value;
4392 tree endtype;
4393 {
4395 {
4400 endtype);
4401 }
4405 else
4407 }
4408 \f
4409 /* Perform appropriate conversions on the initial value of a variable,
4410 store it in the declaration DECL,
4411 and print any error messages that are appropriate.
4412 If the init is invalid, store an ERROR_MARK. */
4414 void
4417 {
4420 /* If variable's type was invalidly declared, just ignore it. */
4426 /* Digest the specified initializer into an expression. */
4430 /* Store the expression if valid; else report error. */
4432 #if 0
4433 /* Note that this is the only place we can detect the error
4434 in a case such as struct foo bar = (struct foo) { x, y };
4435 where there is one initial value which is a constructor expression. */
4437 ;
4439 {
4442 }
4445 {
4448 }
4449 else
4450 {
4452 {
4457 }
4458 }
4459 #endif
4467 /* ANSI wants warnings about out-of-range constant initializers. */
4471 /* Check if we need to set array size from compound literal size. */
4475 {
4483 {
4487 {
4488 /* For int foo[] = (int [3]){1}; we need to set array size
4489 now since later on array initializer will be just the
4490 brace enclosed list of the compound literal. */
4494 }
4495 }
4496 }
4497 }
4498 \f
4499 /* Methods for storing and printing names for error messages. */
4501 /* Implement a spelling stack that allows components of a name to be pushed
4502 and popped. Each element on the stack is this structure. */
4504 struct spelling
4505 {
4507 union
4508 {
4512 };
4514 #define SPELLING_STRING 1
4515 #define SPELLING_MEMBER 2
4516 #define SPELLING_BOUNDS 3
4522 /* Macros to save and restore the spelling stack around push_... functions.
4523 Alternative to SAVE_SPELLING_STACK. */
4525 #define SPELLING_DEPTH() (spelling - spelling_base)
4526 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4528 /* Push an element on the spelling stack with type KIND and assign VALUE
4529 to MEMBER. */
4531 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4532 { \
4533 int depth = SPELLING_DEPTH (); \
4534 \
4535 if (depth >= spelling_size) \
4536 { \
4537 spelling_size += 10; \
4538 if (spelling_base == 0) \
4539 spelling_base \
4540 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4541 else \
4542 spelling_base \
4543 = (struct spelling *) xrealloc (spelling_base, \
4544 spelling_size * sizeof (struct spelling)); \
4545 RESTORE_SPELLING_DEPTH (depth); \
4546 } \
4547 \
4548 spelling->kind = (KIND); \
4549 spelling->MEMBER = (VALUE); \
4550 spelling++; \
4551 }
4553 /* Push STRING on the stack. Printed literally. */
4555 static void
4558 {
4560 }
4562 /* Push a member name on the stack. Printed as '.' STRING. */
4564 static void
4566 tree decl;
4568 {
4572 }
4574 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4576 static void
4579 {
4581 }
4583 /* Compute the maximum size in bytes of the printed spelling. */
4585 static int
4587 {
4592 {
4595 else
4597 }
4600 }
4602 /* Print the spelling to BUFFER and return it. */
4607 {
4613 {
4616 }
4617 else
4618 {
4623 ;
4624 }
4627 }
4629 /* Issue an error message for a bad initializer component.
4630 MSGID identifies the message.
4631 The component name is taken from the spelling stack. */
4633 void
4636 {
4643 }
4645 /* Issue a pedantic warning for a bad initializer component.
4646 MSGID identifies the message.
4647 The component name is taken from the spelling stack. */
4649 void
4652 {
4659 }
4661 /* Issue a warning for a bad initializer component.
4662 MSGID identifies the message.
4663 The component name is taken from the spelling stack. */
4665 static void
4668 {
4675 }
4676 \f
4677 /* Digest the parser output INIT as an initializer for type TYPE.
4678 Return a C expression of type TYPE to represent the initial value.
4680 REQUIRE_CONSTANT requests an error if non-constant initializers or
4681 elements are seen. */
4683 static tree
4687 {
4696 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4697 /* Do not use STRIP_NOPS here. We do not want an enumerator
4698 whose value is 0 to count as a null pointer constant. */
4704 /* Initialization of an array of chars from a string constant
4705 optionally enclosed in braces. */
4708 {
4716 {
4724 {
4727 }
4731 {
4734 }
4740 /* Subtract 1 (or sizeof (wchar_t))
4741 because it's ok to ignore the terminating null char
4742 that is counted in the length of the constant. */
4753 }
4754 }
4756 /* Any type can be initialized
4757 from an expression of the same type, optionally with braces. */
4771 {
4777 {
4778 /* As an extension, allow initializing objects with static storage
4779 duration with compound literals (which are then treated just as
4780 the brace enclosed list they contain). */
4783 }
4787 {
4790 }
4795 /* Compound expressions can only occur here if -pedantic or
4796 -pedantic-errors is specified. In the later case, we always want
4797 an error. In the former case, we simply want a warning. */
4800 {
4801 inside_init
4806 else
4810 }
4813 /* This test catches things like `7 / 0' which
4814 result in an expression for which TREE_CONSTANT
4815 is true, but which is not actually something
4816 that is a legal constant. We really should not
4817 be using this function, because it is a part of
4818 the back-end. Instead, the expression should
4819 already have been turned into ERROR_MARK_NODE. */
4822 {
4825 }
4828 }
4830 /* Handle scalar types, including conversions. */
4834 {
4835 /* Note that convert_for_assignment calls default_conversion
4836 for arrays and functions. We must not call it in the
4837 case where inside_init is a null pointer constant. */
4838 inside_init
4843 {
4846 }
4849 {
4852 }
4855 }
4857 /* Come here only for records and arrays. */
4860 {
4863 }
4867 }
4868 \f
4869 /* Handle initializers that use braces. */
4871 /* Type of object we are accumulating a constructor for.
4872 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4875 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4876 left to fill. */
4879 /* For an ARRAY_TYPE, this is the specified index
4880 at which to store the next element we get. */
4883 /* For an ARRAY_TYPE, this is the maximum index. */
4886 /* For a RECORD_TYPE, this is the first field not yet written out. */
4889 /* For an ARRAY_TYPE, this is the index of the first element
4890 not yet written out. */
4893 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4894 This is so we can generate gaps between fields, when appropriate. */
4897 /* If we are saving up the elements rather than allocating them,
4898 this is the list of elements so far (in reverse order,
4899 most recent first). */
4902 /* 1 if constructor should be incrementally stored into a constructor chain,
4903 0 if all the elements should be kept in AVL tree. */
4906 /* 1 if so far this constructor's elements are all compile-time constants. */
4909 /* 1 if so far this constructor's elements are all valid address constants. */
4912 /* 1 if this constructor is erroneous so far. */
4915 /* 1 if have called defer_addressed_constants. */
4918 /* Structure for managing pending initializer elements, organized as an
4919 AVL tree. */
4921 struct init_node
4922 {
4926 tree purpose;
4927 tree value;
4928 };
4930 /* Tree of pending elements at this constructor level.
4931 These are elements encountered out of order
4932 which belong at places we haven't reached yet in actually
4933 writing the output.
4934 Will never hold tree nodes across GC runs. */
4937 /* The SPELLING_DEPTH of this constructor. */
4940 /* 0 if implicitly pushing constructor levels is allowed. */
4946 /* DECL node for which an initializer is being read.
4947 0 means we are reading a constructor expression
4948 such as (struct foo) {...}. */
4951 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4954 /* Nonzero if this is an initializer for a top-level decl. */
4957 /* Nonzero if there were any member designators in this initializer. */
4960 /* Nesting depth of designator list. */
4963 /* Nonzero if there were diagnosed errors in this designator list. */
4966 \f
4967 /* This stack has a level for each implicit or explicit level of
4968 structuring in the initializer, including the outermost one. It
4969 saves the values of most of the variables above. */
4973 struct constructor_stack
4974 {
4976 tree type;
4977 tree fields;
4978 tree index;
4979 tree max_index;
4980 tree unfilled_index;
4981 tree unfilled_fields;
4982 tree bit_index;
4983 tree elements;
4987 /* If nonzero, this value should replace the entire
4988 constructor at this level. */
4989 tree replacement_value;
4998 };
5002 /* This stack represents designators from some range designator up to
5003 the last designator in the list. */
5005 struct constructor_range_stack
5006 {
5009 tree range_start;
5010 tree index;
5011 tree range_end;
5012 tree fields;
5013 };
5017 /* This stack records separate initializers that are nested.
5018 Nested initializers can't happen in ANSI C, but GNU C allows them
5019 in cases like { ... (struct foo) { ... } ... }. */
5021 struct initializer_stack
5022 {
5024 tree decl;
5028 tree elements;
5036 };
5039 \f
5040 /* Prepare to parse and output the initializer for variable DECL. */
5042 void
5044 tree decl;
5045 tree asmspec_tree;
5047 {
5078 {
5080 require_constant_elements
5082 /* For a scalar, you can always use any value to initialize,
5083 even within braces. */
5089 }
5090 else
5091 {
5095 }
5108 }
5110 void
5112 {
5115 /* Output subconstants (string constants, usually)
5116 that were referenced within this initializer and saved up.
5117 Must do this if and only if we called defer_addressed_constants. */
5121 /* Free the whole constructor stack of this initializer. */
5123 {
5127 }
5132 /* Pop back to the data of the outer initializer (if any). */
5147 }
5148 \f
5149 /* Call here when we see the initializer is surrounded by braces.
5150 This is instead of a call to push_init_level;
5151 it is matched by a call to pop_init_level.
5153 TYPE is the type to initialize, for a constructor expression.
5154 For an initializer for a decl, TYPE is zero. */
5156 void
5158 tree type;
5159 {
5204 {
5206 /* Skip any nameless bit fields at the beginning. */
5213 }
5215 {
5217 {
5218 constructor_max_index
5221 /* Detect non-empty initializations of zero-length arrays. */
5226 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5227 to initialize VLAs will cause a proper error; avoid tree
5228 checking errors as well by setting a safe value. */
5233 constructor_index
5236 }
5237 else
5241 }
5243 {
5244 /* Vectors are like simple fixed-size arrays. */
5245 constructor_max_index =
5249 }
5250 else
5251 {
5252 /* Handle the case of int x = {5}; */
5255 }
5256 }
5257 \f
5258 /* Push down into a subobject, for initialization.
5259 If this is for an explicit set of braces, IMPLICIT is 0.
5260 If it is because the next element belongs at a lower level,
5261 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5263 void
5266 {
5270 /* If we've exhausted any levels that didn't have braces,
5271 pop them now. */
5273 {
5279 && constructor_max_index
5282 else
5284 }
5286 /* Unless this is an explicit brace, we need to preserve previous
5287 content if any. */
5289 {
5296 }
5329 {
5334 }
5336 /* Don't die if an entire brace-pair level is superfluous
5337 in the containing level. */
5339 ;
5342 {
5343 /* Don't die if there are extra init elts at the end. */
5346 else
5347 {
5350 constructor_depth++;
5351 }
5352 }
5354 {
5357 constructor_depth++;
5358 }
5361 {
5366 }
5369 {
5377 }
5380 {
5383 }
5387 {
5389 /* Skip any nameless bit fields at the beginning. */
5396 }
5398 {
5399 /* Vectors are like simple fixed-size arrays. */
5400 constructor_max_index =
5404 }
5406 {
5408 {
5409 constructor_max_index
5412 /* Detect non-empty initializations of zero-length arrays. */
5417 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5418 to initialize VLAs will cause a proper error; avoid tree
5419 checking errors as well by setting a safe value. */
5424 constructor_index
5427 }
5428 else
5433 {
5434 /* We need to split the char/wchar array into individual
5435 characters, so that we don't have to special case it
5436 everywhere. */
5438 }
5439 }
5440 else
5441 {
5445 }
5446 }
5448 /* At the end of an implicit or explicit brace level,
5449 finish up that level of constructor.
5450 If we were outputting the elements as they are read, return 0
5451 from inner levels (process_init_element ignores that),
5452 but return error_mark_node from the outermost level
5453 (that's what we want to put in DECL_INITIAL).
5454 Otherwise, return a CONSTRUCTOR expression. */
5456 tree
5459 {
5464 {
5465 /* When we come to an explicit close brace,
5466 pop any inner levels that didn't have explicit braces. */
5472 }
5476 /* Error for initializing a flexible array member, or a zero-length
5477 array member in an inappropriate context. */
5482 {
5483 /* Silently discard empty initializations. The parser will
5484 already have pedwarned for empty brackets. */
5488 {
5494 /* We have already issued an error message for the existence
5495 of a flexible array member not at the end of the structure.
5496 Discard the initializer so that we do not abort later. */
5499 }
5500 else
5501 /* Zero-length arrays are no longer special, so we should no longer
5502 get here. */
5504 }
5506 /* Warn when some struct elements are implicitly initialized to zero. */
5508 && constructor_type
5511 {
5512 /* Do not warn for flexible array members or zero-length arrays. */
5518 /* Do not warn if this level of the initializer uses member
5519 designators; it is likely to be deliberate. */
5521 {
5525 }
5526 }
5528 /* Now output all pending elements. */
5532 /* Pad out the end of the structure. */
5534 /* If this closes a superfluous brace pair,
5535 just pass out the element between them. */
5538 ;
5543 {
5544 /* A nonincremental scalar initializer--just return
5545 the element, after verifying there is just one. */
5547 {
5551 }
5553 {
5556 }
5557 else
5559 }
5560 else
5561 {
5564 else
5565 {
5572 }
5573 }
5598 {
5602 }
5604 }
5606 /* Common handling for both array range and field name designators.
5607 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5609 static int
5612 {
5613 tree subtype;
5616 /* Don't die if an entire brace-pair level is superfluous
5617 in the containing level. */
5621 /* If there were errors in this designator list already, bail out silently. */
5626 {
5630 /* Designator list starts at the level of closest explicit
5631 braces. */
5636 }
5639 {
5642 }
5646 {
5650 }
5652 {
5654 }
5655 else
5660 {
5663 }
5665 {
5668 }
5673 }
5675 /* If there are range designators in designator list, push a new designator
5676 to constructor_range_stack. RANGE_END is end of such stack range or
5677 NULL_TREE if there is no range designator at this level. */
5679 static void
5681 tree range_end;
5682 {
5697 }
5699 /* Within an array initializer, specify the next index to be initialized.
5700 FIRST is that index. If LAST is nonzero, then initialize a range
5701 of indices, running from FIRST through LAST. */
5703 void
5706 {
5736 else
5737 {
5741 {
5745 {
5748 }
5749 else
5750 {
5754 {
5757 }
5758 }
5759 }
5761 designator_depth++;
5765 }
5766 }
5768 /* Within a struct initializer, specify the next field to be initialized. */
5770 void
5772 tree fieldname;
5773 {
5774 tree tail;
5783 {
5786 }
5790 {
5793 }
5798 else
5799 {
5801 designator_depth++;
5805 }
5806 }
5807 \f
5808 /* Add a new initializer to the tree of pending initializers. PURPOSE
5809 identifies the initializer, either array index or field in a structure.
5810 VALUE is the value of that index or field. */
5812 static void
5815 {
5822 {
5824 {
5830 else
5831 {
5836 }
5837 }
5838 }
5839 else
5840 {
5841 tree bitpos;
5845 {
5851 else
5852 {
5857 }
5858 }
5859 }
5872 {
5876 {
5880 {
5882 {
5883 /* L rotation. */
5896 {
5899 else
5901 }
5902 else
5904 }
5905 else
5906 {
5907 /* LR rotation. */
5929 {
5932 else
5934 }
5935 else
5937 }
5939 }
5940 else
5941 {
5942 /* p->balance == +1; growth of left side balances the node. */
5945 }
5946 }
5948 {
5950 /* Growth propagation from right side. */
5953 {
5955 {
5956 /* R rotation. */
5969 {
5972 else
5974 }
5975 else
5977 }
5979 {
5980 /* RL rotation */
6002 {
6005 else
6007 }
6008 else
6010 }
6012 }
6013 else
6014 {
6015 /* p->balance == -1; growth of right side balances the node. */
6018 }
6019 }
6023 }
6024 }
6026 /* Build AVL tree from a sorted chain. */
6028 static void
6030 {
6031 tree chain;
6041 {
6043 /* Skip any nameless bit fields at the beginning. */
6049 }
6051 {
6053 constructor_unfilled_index
6056 else
6058 }
6060 }
6062 /* Build AVL tree from a string constant. */
6064 static void
6066 tree str;
6067 {
6082 else
6093 {
6095 {
6098 }
6099 else
6100 {
6104 {
6107 else
6112 }
6113 }
6116 {
6119 {
6121 {
6124 }
6125 }
6127 {
6130 }
6135 }
6140 }
6143 }
6145 /* Return value of FIELD in pending initializer or zero if the field was
6146 not initialized yet. */
6148 static tree
6150 tree field;
6151 {
6155 {
6162 {
6167 else
6169 }
6170 }
6172 {
6176 && (!constructor_unfilled_fields
6183 {
6188 else
6190 }
6191 }
6193 {
6197 }
6199 }
6201 /* "Output" the next constructor element.
6202 At top level, really output it to assembler code now.
6203 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6204 TYPE is the data type that the containing data type wants here.
6205 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6207 PENDING if non-nil means output pending elements that belong
6208 right after this element. (PENDING is normally 1;
6209 it is 0 while outputting pending elements, to avoid recursion.) */
6211 static void
6215 {
6227 {
6228 /* As an extension, allow initializing objects with static storage
6229 duration with compound literals (which are then treated just as
6230 the brace enclosed list they contain). */
6233 }
6247 {
6250 }
6255 /* If this field is empty (and not at the end of structure),
6256 don't do anything other than checking the initializer. */
6267 {
6270 }
6272 /* If this element doesn't come next in sequence,
6273 put it on constructor_pending_elts. */
6275 && (!constructor_incremental
6277 {
6284 }
6286 && (!constructor_incremental
6288 {
6289 /* We do this for records but not for unions. In a union,
6290 no matter which field is specified, it can be initialized
6291 right away since it starts at the beginning of the union. */
6293 {
6296 else
6297 {
6305 }
6306 }
6310 }
6313 {
6317 /* We can have just one union field set. */
6319 }
6321 /* Otherwise, output this element either to
6322 constructor_elements or to the assembler file. */
6326 constructor_elements
6329 /* Advance the variable that indicates sequential elements output. */
6331 constructor_unfilled_index
6333 bitsize_one_node);
6335 {
6336 constructor_unfilled_fields
6339 /* Skip any nameless bit fields. */
6343 constructor_unfilled_fields =
6345 }
6349 /* Now output any pending elements which have become next. */
6352 }
6354 /* Output any pending elements which have become next.
6355 As we output elements, constructor_unfilled_{fields,index}
6356 advances, which may cause other elements to become next;
6357 if so, they too are output.
6359 If ALL is 0, we return when there are
6360 no more pending elements to output now.
6362 If ALL is 1, we output space as necessary so that
6363 we can output all the pending elements. */
6365 static void
6368 {
6370 tree next;
6372 retry:
6374 /* Look thru the whole pending tree.
6375 If we find an element that should be output now,
6376 output it. Otherwise, set NEXT to the element
6377 that comes first among those still pending. */
6381 {
6383 {
6385 constructor_unfilled_index))
6391 {
6392 /* Advance to the next smaller node. */
6395 else
6396 {
6397 /* We have reached the smallest node bigger than the
6398 current unfilled index. Fill the space first. */
6401 }
6402 }
6403 else
6404 {
6405 /* Advance to the next bigger node. */
6408 else
6409 {
6410 /* We have reached the biggest node in a subtree. Find
6411 the parent of it, which is the next bigger node. */
6417 {
6420 }
6421 }
6422 }
6423 }
6426 {
6429 /* If the current record is complete we are done. */
6435 /* We can't compare fields here because there might be empty
6436 fields in between. */
6438 {
6442 }
6444 {
6445 /* Advance to the next smaller node. */
6448 else
6449 {
6450 /* We have reached the smallest node bigger than the
6451 current unfilled field. Fill the space first. */
6454 }
6455 }
6456 else
6457 {
6458 /* Advance to the next bigger node. */
6461 else
6462 {
6463 /* We have reached the biggest node in a subtree. Find
6464 the parent of it, which is the next bigger node. */
6471 {
6474 }
6475 }
6476 }
6477 }
6478 }
6480 /* Ordinarily return, but not if we want to output all
6481 and there are elements left. */
6485 /* If it's not incremental, just skip over the gap, so that after
6486 jumping to retry we will output the next successive element. */
6493 /* ELT now points to the node in the pending tree with the next
6494 initializer to output. */
6496 }
6497 \f
6498 /* Add one non-braced element to the current constructor level.
6499 This adjusts the current position within the constructor's type.
6500 This may also start or terminate implicit levels
6501 to handle a partly-braced initializer.
6503 Once this has found the correct level for the new element,
6504 it calls output_init_element. */
6506 void
6508 tree value;
6509 {
6516 /* Handle superfluous braces around string cst as in
6517 char x[] = {"foo"}; */
6519 && constructor_type
6523 {
6528 }
6531 {
6534 }
6536 /* Ignore elements of a brace group if it is entirely superfluous
6537 and has already been diagnosed. */
6541 /* If we've exhausted any levels that didn't have braces,
6542 pop them now. */
6544 {
6552 constructor_index)))
6554 else
6556 }
6558 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6560 {
6561 /* If value is a compound literal and we'll be just using its
6562 content, don't put it into a SAVE_EXPR. */
6564 || !require_constant_value
6567 }
6570 {
6572 {
6573 tree fieldtype;
6577 {
6580 }
6587 /* Error for non-static initialization of a flexible array member. */
6589 && !require_constant_value
6592 {
6595 }
6597 /* Accept a string constant to initialize a subarray. */
6603 /* Otherwise, if we have come to a subaggregate,
6604 and we don't have an element of its type, push into it. */
6610 {
6613 }
6616 {
6620 }
6621 else
6622 /* Do the bookkeeping for an element that was
6623 directly output as a constructor. */
6624 {
6625 /* For a record, keep track of end position of last field. */
6627 constructor_bit_index
6632 /* If the current field was the first one not yet written out,
6633 it isn't now, so update. */
6635 {
6637 /* Skip any nameless bit fields. */
6641 constructor_unfilled_fields =
6643 }
6644 }
6647 /* Skip any nameless bit fields at the beginning. */
6652 }
6654 {
6655 tree fieldtype;
6659 {
6662 }
6669 /* Warn that traditional C rejects initialization of unions.
6670 We skip the warning if the value is zero. This is done
6671 under the assumption that the zero initializer in user
6672 code appears conditioned on e.g. __STDC__ to avoid
6673 "missing initializer" warnings and relies on default
6674 initialization to zero in the traditional C case.
6675 We also skip the warning if the initializer is designated,
6676 again on the assumption that this must be conditional on
6677 __STDC__ anyway (and we've already complained about the
6678 member-designator already). */
6683 /* Accept a string constant to initialize a subarray. */
6689 /* Otherwise, if we have come to a subaggregate,
6690 and we don't have an element of its type, push into it. */
6696 {
6699 }
6702 {
6706 }
6707 else
6708 /* Do the bookkeeping for an element that was
6709 directly output as a constructor. */
6710 {
6713 }
6716 }
6718 {
6722 /* Accept a string constant to initialize a subarray. */
6728 /* Otherwise, if we have come to a subaggregate,
6729 and we don't have an element of its type, push into it. */
6735 {
6738 }
6743 {
6746 }
6748 /* Now output the actual element. */
6750 {
6754 }
6756 constructor_index
6760 /* If we are doing the bookkeeping for an element that was
6761 directly output as a constructor, we must update
6762 constructor_unfilled_index. */
6764 }
6766 {
6769 /* Do a basic check of initializer size. Note that vectors
6770 always have a fixed size derived from their type. */
6772 {
6775 }
6777 /* Now output the actual element. */
6781 constructor_index
6785 /* If we are doing the bookkeeping for an element that was
6786 directly output as a constructor, we must update
6787 constructor_unfilled_index. */
6789 }
6791 /* Handle the sole element allowed in a braced initializer
6792 for a scalar variable. */
6794 {
6797 }
6798 else
6799 {
6803 }
6805 /* Handle range initializers either at this level or anywhere higher
6806 in the designator stack. */
6808 {
6815 {
6819 }
6823 {
6827 }
6834 {
6838 {
6841 }
6849 }
6854 }
6857 }
6860 }
6861 \f
6862 /* Build a simple asm-statement, from one string literal. */
6863 tree
6865 tree expr;
6866 {
6873 {
6874 tree stmt;
6876 /* Simple asm statements are treated as volatile. */
6881 }
6885 }
6887 /* Build an asm-statement, whose components are a CV_QUALIFIER, a
6888 STRING, some OUTPUTS, some INPUTS, and some CLOBBERS. */
6890 tree
6892 tree cv_qualifier;
6893 tree string;
6894 tree outputs;
6895 tree inputs;
6896 tree clobbers;
6897 {
6898 tree tail;
6901 {
6904 }
6908 {
6912 }
6914 /* We can remove output conversions that change the type,
6915 but not the mode. */
6917 {
6923 /* Allow conversions as LHS here. build_modify_expr as called below
6924 will do the right thing with them. */
6935 }
6937 /* Remove output conversions that change the type but not the mode. */
6939 {
6943 }
6945 /* Perform default conversions on array and function inputs.
6946 Don't do this for other types as it would screw up operands
6947 expected to be in memory. */
6953 }
6955 /* Expand an ASM statement with operands, handling output operands
6956 that are not variables or INDIRECT_REFS by transforming such
6957 cases into cases that expand_asm_operands can handle.
6959 Arguments are same as for expand_asm_operands. */
6961 void
6967 {
6970 /* o[I] is the place that output number I should be written. */
6972 tree tail;
6974 /* Record the contents of OUTPUTS before it is modified. */
6976 {
6980 }
6982 /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of
6983 OUTPUTS some trees for where the values were actually stored. */
6986 /* Copy all the intermediate outputs into the specified outputs. */
6988 {
6990 {
6995 /* Restore the original value so that it's correct the next
6996 time we expand this function. */
6998 }
6999 /* Detect modification of read-only values.
7000 (Otherwise done by build_modify_expr.) */
7001 else
7002 {
7010 }
7011 }
7013 /* Those MODIFY_EXPRs could do autoincrements. */
7015 }
7016 \f
7017 /* Expand a C `return' statement.
7018 RETVAL is the expression for what to return,
7019 or a null pointer for `return;' with no value. */
7021 tree
7023 tree retval;
7024 {
7031 {
7036 }
7038 {
7042 }
7043 else
7044 {
7048 tree inner;
7056 /* Strip any conversions, additions, and subtractions, and see if
7057 we are returning the address of a local variable. Warn if so. */
7059 {
7061 {
7068 /* If the second operand of the MINUS_EXPR has a pointer
7069 type (or is converted from it), this may be valid, so
7070 don't give a warning. */
7071 {
7085 }
7102 }
7105 }
7108 }
7111 }
7112 \f
7114 /* The SWITCH_STMT being built. */
7115 tree switch_stmt;
7116 /* A splay-tree mapping the low element of a case range to the high
7117 element, or NULL_TREE if there is no high element. Used to
7118 determine whether or not a new case label duplicates an old case
7119 label. We need a tree, rather than simply a hash table, because
7120 of the GNU case range extension. */
7121 splay_tree cases;
7122 /* The next node on the stack. */
7124 };
7126 /* A stack of the currently active switch statements. The innermost
7127 switch statement is on the top of the stack. There is no need to
7128 mark the stack for garbage collection because it is only active
7129 during the processing of the body of a function, and we never
7130 collect at that point. */
7134 /* Start a C switch statement, testing expression EXP. Return the new
7135 SWITCH_STMT. */
7137 tree
7139 tree exp;
7140 {
7146 {
7152 {
7155 }
7156 else
7157 {
7167 }
7168 }
7170 /* Add this new SWITCH_STMT to the stack. */
7178 }
7180 /* Process a case label. */
7182 tree
7184 tree low_value;
7185 tree high_value;
7186 {
7190 {
7199 {
7200 /* Attach the first case label to the SWITCH_BODY. */
7203 }
7204 }
7207 else
7211 }
7213 /* Finish the switch statement. */
7215 void
7217 {
7220 /* Rechain the next statements to the SWITCH_STMT. */
7223 /* Pop the stack. */
7227 }