| blob | c4e482ee240b990d186387753e54890b2be59309 |
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, 2003 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. */
88 \f
89 /* Do `exp = require_complete_type (exp);' to make sure exp
90 does not have an incomplete type. (That includes void types.) */
92 tree
94 tree value;
95 {
101 /* First, detect a valid value with a complete type. */
107 }
109 /* Print an error message for invalid use of an incomplete type.
110 VALUE is the expression that was used (or 0 if that isn't known)
111 and TYPE is the type that was invalid. */
113 void
115 tree value;
116 tree type;
117 {
120 /* Avoid duplicate error message. */
128 else
129 {
130 retry:
131 /* We must print an error message. Be clever about what it says. */
134 {
153 {
155 {
158 }
161 }
167 }
172 else
173 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
176 }
177 }
179 /* Given a type, apply default promotions wrt unnamed function
180 arguments and return the new type. */
182 tree
184 tree type;
185 {
190 {
191 /* Preserve unsignedness if not really getting any wider. */
196 }
199 }
201 /* Return a variant of TYPE which has all the type qualifiers of LIKE
202 as well as those of TYPE. */
204 static tree
207 {
210 }
211 \f
212 /* Return the common type of two types.
213 We assume that comptypes has already been done and returned 1;
214 if that isn't so, this may crash. In particular, we assume that qualifiers
215 match.
217 This is the type for the result of most arithmetic operations
218 if the operands have the given two types. */
220 tree
223 {
226 tree attributes;
228 /* Save time if the two types are the same. */
232 /* If one type is nonsense, use the other. */
238 /* Merge the attributes. */
241 /* Treat an enum type as the unsigned integer type of the same width. */
251 /* If one type is complex, form the common type of the non-complex
252 components, then make that complex. Use T1 or T2 if it is the
253 required type. */
255 {
264 else
266 attributes);
267 }
270 {
273 /* If only one is real, use it as the result. */
281 /* Both real or both integers; use the one with greater precision. */
288 /* Same precision. Prefer longs to ints even when same size. */
293 attributes);
297 {
298 /* But preserve unsignedness from the other type,
299 since long cannot hold all the values of an unsigned int. */
302 else
305 }
307 /* Likewise, prefer long double to double even if same size. */
311 attributes);
313 /* Otherwise prefer the unsigned one. */
317 else
321 /* For two pointers, do this recursively on the target type,
322 and combine the qualifiers of the two types' targets. */
323 /* This code was turned off; I don't know why.
324 But ANSI C specifies doing this with the qualifiers.
325 So I turned it on again. */
326 {
336 }
337 #if 0
340 #endif
343 {
345 /* Save space: see if the result is identical to one of the args. */
350 /* Merge the element types, and have a size if either arg has one. */
353 }
356 /* Function types: prefer the one that specified arg types.
357 If both do, merge the arg types. Also merge the return types. */
358 {
366 /* Save space: see if the result is identical to one of the args. */
372 /* Simple way if one arg fails to specify argument types. */
374 {
377 }
379 {
382 }
384 /* If both args specify argument types, we must merge the two
385 lists, argument by argument. */
400 {
401 /* A null type means arg type is not specified.
402 Take whatever the other function type has. */
404 {
407 }
409 {
412 }
414 /* Given wait (union {union wait *u; int *i} *)
415 and wait (union wait *),
416 prefer union wait * as type of parm. */
419 {
420 tree memb;
424 {
429 }
430 }
433 {
434 tree memb;
438 {
443 }
444 }
446 parm_done: ;
447 }
452 /* ... falls through ... */
453 }
457 }
459 }
460 \f
461 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
462 or various other operations. Return 2 if they are compatible
463 but a warning may be needed if you use them together. */
465 int
468 {
473 /* Suppress errors caused by previously reported errors. */
479 /* If either type is the internal version of sizetype, return the
480 language version. */
489 /* Treat an enum type as the integer type of the same width and
490 signedness. */
500 /* Different classes of types can't be compatible. */
504 /* Qualifiers must match. */
509 /* Allow for two different type nodes which have essentially the same
510 definition. Note that we already checked for equality of the type
511 qualifiers (just above). */
516 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
520 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
524 {
535 {
542 /* Target types must match incl. qualifiers. */
547 /* Sizes must match unless one is missing or variable. */
554 d1_variable = (! d1_zero
557 d2_variable = (! d2_zero
571 }
579 /* The target might allow certain vector types to be compatible. */
586 }
588 }
590 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
591 ignoring their qualifiers. REFLEXIVE is only used by ObjC - set it
592 to 1 or 0 depending if the check of the pointer types is meant to
593 be reflexive or not (typically, assignments are not reflexive,
594 while comparisons are reflexive).
595 */
597 static int
601 {
604 /* Give objc_comptypes a crack at letting these types through. */
614 }
615 \f
616 /* Subroutines of `comptypes'. */
618 /* Return 1 if two function types F1 and F2 are compatible.
619 If either type specifies no argument types,
620 the other must specify a fixed number of self-promoting arg types.
621 Otherwise, if one type specifies only the number of arguments,
622 the other must specify that number of self-promoting arg types.
623 Otherwise, the argument types must match. */
625 static int
628 {
630 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
638 /* 'volatile' qualifiers on a function's return type mean the function
639 is noreturn. */
655 /* An unspecified parmlist matches any specified parmlist
656 whose argument types don't need default promotions. */
659 {
662 /* If one of these types comes from a non-prototype fn definition,
663 compare that with the other type's arglist.
664 If they don't match, ask for a warning (but no error). */
669 }
671 {
678 }
680 /* Both types have argument lists: compare them and propagate results. */
683 }
685 /* Check two lists of types for compatibility,
686 returning 0 for incompatible, 1 for compatible,
687 or 2 for compatible with warning. */
689 static int
692 {
693 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
698 {
701 /* If one list is shorter than the other,
702 they fail to match. */
705 /* A null pointer instead of a type
706 means there is supposed to be an argument
707 but nothing is specified about what type it has.
708 So match anything that self-promotes. */
710 {
713 }
715 {
718 }
721 {
722 /* Allow wait (union {union wait *u; int *i} *)
723 and wait (union wait *) to be compatible. */
730 {
731 tree memb;
738 }
745 {
746 tree memb;
753 }
754 else
756 }
758 /* comptypes said ok, but record if it said to warn. */
764 }
765 }
766 \f
767 /* Compute the size to increment a pointer by. */
769 tree
771 tree type;
772 {
779 {
782 }
784 /* Convert in case a char is more than one unit. */
788 }
789 \f
790 /* Return either DECL or its known constant value (if it has one). */
792 tree
794 tree decl;
795 {
797 in a place where a variable is invalid. */
803 /* This is invalid if initial value is not constant.
804 If it has either a function call, a memory reference,
805 or a variable, then re-evaluating it could give different results. */
807 /* Check for cases where this is sub-optimal, even though valid. */
811 }
813 /* Return either DECL or its known constant value (if it has one), but
814 return DECL if pedantic or DECL has mode BLKmode. This is for
815 bug-compatibility with the old behavior of decl_constant_value
816 (before GCC 3.0); every use of this function is a bug and it should
817 be removed before GCC 3.1. It is not appropriate to use pedantic
818 in a way that affects optimization, and BLKmode is probably not the
819 right test for avoiding misoptimizations either. */
821 static tree
823 tree decl;
824 {
827 else
829 }
832 /* Perform the default conversion of arrays and functions to pointers.
833 Return the result of converting EXP. For any other expression, just
834 return EXP. */
836 static tree
838 tree exp;
839 {
840 tree orig_exp;
845 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
846 an lvalue.
848 Do not use STRIP_NOPS here! It will remove conversions from pointer
849 to integer and cause infinite recursion. */
854 {
858 }
860 /* Preserve the original expression code. */
865 {
867 }
869 {
870 tree adr;
872 tree ptrtype;
878 {
881 }
884 restype
895 {
899 }
903 {
904 /* Before C99, non-lvalue arrays do not decay to pointers.
905 Normally, using such an array would be invalid; but it can
906 be used correctly inside sizeof or as a statement expression.
907 Thus, do not give an error here; an error will result later. */
909 }
914 {
915 /* ??? This is not really quite correct
916 in that the type of the operand of ADDR_EXPR
917 is not the target type of the type of the ADDR_EXPR itself.
918 Question is, can this lossage be avoided? */
925 }
926 /* This way is better for a COMPONENT_REF since it can
927 simplify the offset for a component. */
930 }
932 }
934 /* Perform default promotions for C data used in expressions.
935 Arrays and functions are converted to pointers;
936 enumeral types or short or char, to int.
937 In addition, manifest constants symbols are replaced by their values. */
939 tree
941 tree exp;
942 {
943 tree orig_exp;
950 /* Constants can be used directly unless they're not loadable. */
954 /* Replace a nonvolatile const static variable with its value unless
955 it is an array, in which case we must be sure that taking the
956 address of the array produces consistent results. */
958 {
961 }
963 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
964 an lvalue.
966 Do not use STRIP_NOPS here! It will remove conversions from pointer
967 to integer and cause infinite recursion. */
974 /* Preserve the original expression code. */
978 /* Normally convert enums to int,
979 but convert wide enums to something wider. */
981 {
989 }
993 /* If it's thinner than an int, promote it like a
994 c_promoting_integer_type_p, otherwise leave it alone. */
1000 {
1001 /* Preserve unsignedness if not really getting any wider. */
1007 }
1010 {
1013 }
1015 }
1016 \f
1017 /* Look up COMPONENT in a structure or union DECL.
1019 If the component name is not found, returns NULL_TREE. Otherwise,
1020 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1021 stepping down the chain to the component, which is in the last
1022 TREE_VALUE of the list. Normally the list is of length one, but if
1023 the component is embedded within (nested) anonymous structures or
1024 unions, the list steps down the chain to the component. */
1026 static tree
1029 {
1031 tree field;
1033 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1034 to the field elements. Use a binary search on this array to quickly
1035 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1036 will always be set for structures which have many elements. */
1039 {
1047 {
1052 {
1053 /* Step through all anon unions in linear fashion. */
1055 {
1059 {
1064 }
1065 }
1067 /* Entire record is only anon unions. */
1071 /* Restart the binary search, with new lower bound. */
1073 }
1079 else
1081 }
1087 }
1088 else
1089 {
1091 {
1095 {
1100 }
1104 }
1108 }
1111 }
1113 /* Make an expression to refer to the COMPONENT field of
1114 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1116 tree
1119 {
1123 tree ref;
1125 /* If DATUM is a COMPOUND_EXPR, move our reference inside it.
1126 If pedantic ensure that the arguments are not lvalues; otherwise,
1127 if the component is an array, it would wrongly decay to a pointer in
1128 C89 mode.
1129 We cannot do this with a COND_EXPR, because in a conditional expression
1130 the default promotions are applied to both sides, and this would yield
1131 the wrong type of the result; for example, if the components have
1132 type "char". */
1134 {
1136 {
1140 }
1143 }
1145 /* See if there is a field or component with name COMPONENT. */
1148 {
1150 {
1153 }
1158 {
1163 }
1165 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1166 This might be better solved in future the way the C++ front
1167 end does it - by giving the anonymous entities each a
1168 separate name and type, and then have build_component_ref
1169 recursively call itself. We can't do that here. */
1170 do
1171 {
1189 }
1193 }
1199 }
1200 \f
1201 /* Given an expression PTR for a pointer, return an expression
1202 for the value pointed to.
1203 ERRORSTRING is the name of the operator to appear in error messages. */
1205 tree
1207 tree ptr;
1209 {
1214 {
1219 else
1220 {
1225 {
1228 }
1232 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1233 so that we get the proper error message if the result is used
1234 to assign to. Also, &* is supposed to be a no-op.
1235 And ANSI C seems to specify that the type of the result
1236 should be the const type. */
1237 /* A de-reference of a pointer to const is not a const. It is valid
1238 to change it via some other pointer. */
1244 }
1245 }
1249 }
1251 /* This handles expressions of the form "a[i]", which denotes
1252 an array reference.
1254 This is logically equivalent in C to *(a+i), but we may do it differently.
1255 If A is a variable or a member, we generate a primitive ARRAY_REF.
1256 This avoids forcing the array out of registers, and can work on
1257 arrays that are not lvalues (for example, members of structures returned
1258 by functions). */
1260 tree
1263 {
1265 {
1268 }
1276 {
1279 /* Subscripting with type char is likely to lose
1280 on a machine where chars are signed.
1281 So warn on any machine, but optionally.
1282 Don't warn for unsigned char since that type is safe.
1283 Don't warn for signed char because anyone who uses that
1284 must have done so deliberately. */
1289 /* Apply default promotions *after* noticing character types. */
1292 /* Require integer *after* promotion, for sake of enums. */
1294 {
1297 }
1299 /* An array that is indexed by a non-constant
1300 cannot be stored in a register; we must be able to do
1301 address arithmetic on its address.
1302 Likewise an array of elements of variable size. */
1306 {
1309 }
1310 /* An array that is indexed by a constant value which is not within
1311 the array bounds cannot be stored in a register either; because we
1312 would get a crash in store_bit_field/extract_bit_field when trying
1313 to access a non-existent part of the register. */
1317 {
1320 }
1323 {
1331 }
1335 /* Array ref is const/volatile if the array elements are
1336 or if the array is. */
1345 /* This was added by rms on 16 Nov 91.
1346 It fixes vol struct foo *a; a->elts[1]
1347 in an inline function.
1348 Hope it doesn't break something else. */
1351 }
1353 {
1357 /* Do the same warning check as above, but only on the part that's
1358 syntactically the index and only if it is also semantically
1359 the index. */
1365 /* Put the integer in IND to simplify error checking. */
1367 {
1371 }
1378 {
1381 }
1383 {
1386 }
1390 }
1391 }
1392 \f
1393 /* Issue an error message for a reference to an undeclared variable ID,
1394 including a reference to a builtin outside of function-call context.
1395 Arrange to suppress further errors for the same identifier. */
1396 static void
1398 tree id;
1399 {
1401 {
1405 }
1406 else
1407 {
1412 {
1416 }
1418 /* Set IDENTIFIER_SYMBOL_VALUE (id) to error_mark_node
1419 at function scope. This suppresses further warnings
1420 about this undeclared identifier in this function. */
1422 }
1423 }
1425 /* Build an external reference to identifier ID. FUN indicates
1426 whether this will be used for a function call. */
1427 tree
1429 tree id;
1431 {
1432 tree ref;
1437 {
1438 /* Properly declared variable or function reference. */
1442 {
1446 }
1447 else
1449 }
1453 /* Implicit function declaration. */
1456 /* Don't complain about something that's already been
1457 complained about. */
1459 else
1460 {
1463 }
1476 {
1479 }
1485 {
1490 }
1493 }
1495 /* Build a function call to function FUNCTION with parameters PARAMS.
1496 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1497 TREE_VALUE of each node is a parameter-expression.
1498 FUNCTION's data type may be a function type or a pointer-to-function. */
1500 tree
1503 {
1505 tree coerced_params;
1508 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1511 /* Convert anything with function type to a pointer-to-function. */
1513 {
1516 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1517 (because calling an inline function does not mean the function
1518 needs to be separately compiled). */
1524 }
1525 else
1535 {
1538 }
1543 /* fntype now gets the type of function pointed to. */
1546 /* Convert the parameters to the types declared in the
1547 function prototype, or apply default promotions. */
1549 coerced_params
1552 /* Check that the arguments to the function are valid. */
1556 /* Recognize certain built-in functions so we can make tree-codes
1557 other than CALL_EXPR. We do this when it enables fold-const.c
1558 to do something useful. */
1563 {
1568 }
1578 }
1579 \f
1580 /* Convert the argument expressions in the list VALUES
1581 to the types in the list TYPELIST. The result is a list of converted
1582 argument expressions.
1584 If TYPELIST is exhausted, or when an element has NULL as its type,
1585 perform the default conversions.
1587 PARMLIST is the chain of parm decls for the function being called.
1588 It may be 0, if that info is not available.
1589 It is used only for generating error messages.
1591 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1593 This is also where warnings about wrong number of args are generated.
1595 Both VALUES and the returned value are chains of TREE_LIST nodes
1596 with the elements of the list in the TREE_VALUE slots of those nodes. */
1598 static tree
1601 {
1606 /* Scan the given expressions and types, producing individual
1607 converted arguments and pushing them on RESULT in reverse order. */
1610 valtail;
1612 {
1617 {
1621 else
1624 }
1626 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1627 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1628 to convert automatically to a pointer. */
1637 {
1638 /* Formal parm type is specified by a function prototype. */
1639 tree parmval;
1642 {
1645 }
1646 else
1647 {
1648 /* Optionally warn about conversions that
1649 differ from the default conversions. */
1651 {
1656 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1659 warn_for_assignment ("%s as integer rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1662 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1665 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1668 warn_for_assignment ("%s as complex rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1671 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1672 /* ??? At some point, messages should be written about
1673 conversions between complex types, but that's too messy
1674 to do now. */
1677 {
1678 /* Warn if any argument is passed as `float',
1679 since without a prototype it would be `double'. */
1681 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1682 }
1683 /* Detect integer changing in width or signedness.
1684 These warnings are only activated with
1685 -Wconversion, not with -Wtraditional. */
1688 {
1695 /* No warning if function asks for enum
1696 and the actual arg is that enum type. */
1697 ;
1699 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1701 ;
1702 /* Don't complain if the formal parameter type
1703 is an enum, because we can't tell now whether
1704 the value was an enum--even the same enum. */
1706 ;
1709 /* Change in signedness doesn't matter
1710 if a constant value is unaffected. */
1711 ;
1712 /* Likewise for a constant in a NOP_EXPR. */
1716 ;
1721 /* Change in signedness doesn't matter
1722 if an enum value is unaffected. */
1723 ;
1724 #endif
1725 /* If the value is extended from a narrower
1726 unsigned type, it doesn't matter whether we
1727 pass it as signed or unsigned; the value
1728 certainly is the same either way. */
1731 ;
1734 else
1736 }
1737 }
1747 }
1749 }
1753 /* Convert `float' to `double'. */
1755 else
1756 /* Convert `short' and `char' to full-size `int'. */
1761 }
1764 {
1768 else
1770 }
1773 }
1774 \f
1775 /* This is the entry point used by the parser
1776 for binary operators in the input.
1777 In addition to constructing the expression,
1778 we check for operands that were written with other binary operators
1779 in a way that is likely to confuse the user. */
1781 tree
1785 {
1802 /* Check for cases such as x+y<<z which users are likely
1803 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1804 is cleared to prevent these warnings. */
1806 {
1808 {
1812 }
1815 {
1819 }
1822 {
1828 /* Check cases like x|y==z */
1831 }
1834 {
1840 /* Check cases like x^y==z */
1843 }
1846 {
1850 /* Check cases like x&y==z */
1853 }
1854 }
1856 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1867 /* Record the code that was specified in the source,
1868 for the sake of warnings about confusing nesting. */
1871 else
1872 {
1874 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1875 so that convert_for_assignment wouldn't strip it.
1876 That way, we got warnings for things like p = (1 - 1).
1877 But it turns out we should not get those warnings. */
1881 }
1884 }
1886 /* Build a binary-operation expression without default conversions.
1887 CODE is the kind of expression to build.
1888 This function differs from `build' in several ways:
1889 the data type of the result is computed and recorded in it,
1890 warnings are generated if arg data types are invalid,
1891 special handling for addition and subtraction of pointers is known,
1892 and some optimization is done (operations on narrow ints
1893 are done in the narrower type when that gives the same result).
1894 Constant folding is also done before the result is returned.
1896 Note that the operands will never have enumeral types, or function
1897 or array types, because either they will have the default conversions
1898 performed or they have both just been converted to some other type in which
1899 the arithmetic is to be done. */
1901 tree
1906 {
1911 /* Expression code to give to the expression when it is built.
1912 Normally this is CODE, which is what the caller asked for,
1913 but in some special cases we change it. */
1916 /* Data type in which the computation is to be performed.
1917 In the simplest cases this is the common type of the arguments. */
1920 /* Nonzero means operands have already been type-converted
1921 in whatever way is necessary.
1922 Zero means they need to be converted to RESULT_TYPE. */
1925 /* Nonzero means create the expression with this type, rather than
1926 RESULT_TYPE. */
1929 /* Nonzero means after finally constructing the expression
1930 convert it to this type. */
1933 /* Nonzero if this is an operation like MIN or MAX which can
1934 safely be computed in short if both args are promoted shorts.
1935 Also implies COMMON.
1936 -1 indicates a bitwise operation; this makes a difference
1937 in the exact conditions for when it is safe to do the operation
1938 in a narrower mode. */
1941 /* Nonzero if this is a comparison operation;
1942 if both args are promoted shorts, compare the original shorts.
1943 Also implies COMMON. */
1946 /* Nonzero if this is a right-shift operation, which can be computed on the
1947 original short and then promoted if the operand is a promoted short. */
1950 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1954 {
1957 }
1958 else
1959 {
1962 }
1967 /* The expression codes of the data types of the arguments tell us
1968 whether the arguments are integers, floating, pointers, etc. */
1972 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1976 /* If an error was already reported for one of the arguments,
1977 avoid reporting another error. */
1983 {
1985 /* Handle the pointer + int case. */
1990 else
1995 /* Subtraction of two similar pointers.
1996 We must subtract them as integers, then divide by object size. */
2000 /* Handle pointer minus int. Just like pointer plus int. */
2003 else
2016 /* Floating point division by zero is a legitimate way to obtain
2017 infinities and NaNs. */
2025 {
2028 else
2029 /* Although it would be tempting to shorten always here, that
2030 loses on some targets, since the modulo instruction is
2031 undefined if the quotient can't be represented in the
2032 computation mode. We shorten only if unsigned or if
2033 dividing by something we know != -1. */
2038 }
2057 {
2058 /* Although it would be tempting to shorten always here, that loses
2059 on some targets, since the modulo instruction is undefined if the
2060 quotient can't be represented in the computation mode. We shorten
2061 only if unsigned or if dividing by something we know != -1. */
2066 }
2078 {
2079 /* Result of these operations is always an int,
2080 but that does not mean the operands should be
2081 converted to ints! */
2086 }
2089 /* Shift operations: result has same type as first operand;
2090 always convert second operand to int.
2091 Also set SHORT_SHIFT if shifting rightward. */
2095 {
2097 {
2100 else
2101 {
2107 }
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 }
2123 {
2125 {
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 }
2147 {
2149 {
2154 }
2156 /* Use the type of the value to be shifted. */
2158 /* Convert the shift-count to an integer, regardless of size
2159 of value being shifted. */
2162 /* Avoid converting op1 to result_type later. */
2164 }
2171 /* Result of comparison is always int,
2172 but don't convert the args to int! */
2182 {
2185 /* Anything compares with void *. void * compares with anything.
2186 Otherwise, the targets must be compatible
2187 and both must be object or both incomplete. */
2191 {
2192 /* op0 != orig_op0 detects the case of something
2193 whose value is 0 but which isn't a valid null ptr const. */
2197 }
2199 {
2203 }
2204 else
2209 }
2217 {
2220 }
2222 {
2225 }
2234 {
2236 {
2241 }
2242 else
2243 {
2246 }
2247 }
2259 {
2261 {
2269 }
2270 else
2271 {
2274 }
2275 }
2278 {
2282 }
2285 {
2289 }
2291 {
2294 }
2296 {
2299 }
2311 {
2314 }
2320 }
2324 &&
2327 {
2333 /* For certain operations (which identify themselves by shorten != 0)
2334 if both args were extended from the same smaller type,
2335 do the arithmetic in that type and then extend.
2337 shorten !=0 and !=1 indicates a bitwise operation.
2338 For them, this optimization is safe only if
2339 both args are zero-extended or both are sign-extended.
2340 Otherwise, we might change the result.
2341 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2342 but calculated in (unsigned short) it would be (unsigned short)-1. */
2345 {
2349 /* UNS is 1 if the operation to be done is an unsigned one. */
2351 tree type;
2355 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2356 but it *requires* conversion to FINAL_TYPE. */
2367 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2369 /* For bitwise operations, signedness of nominal type
2370 does not matter. Consider only how operands were extended. */
2374 /* Note that in all three cases below we refrain from optimizing
2375 an unsigned operation on sign-extended args.
2376 That would not be valid. */
2378 /* Both args variable: if both extended in same way
2379 from same width, do it in that width.
2380 Do it unsigned if args were zero-extended. */
2387 result_type
2388 = c_common_signed_or_unsigned_type
2394 && (type
2403 && (type
2408 }
2410 /* Shifts can be shortened if shifting right. */
2413 {
2423 /* We can shorten only if the shift count is less than the
2424 number of bits in the smaller type size. */
2426 /* We cannot drop an unsigned shift after sign-extension. */
2428 {
2429 /* Do an unsigned shift if the operand was zero-extended. */
2430 result_type
2433 /* Convert value-to-be-shifted to that type. */
2437 }
2438 }
2440 /* Comparison operations are shortened too but differently.
2441 They identify themselves by setting short_compare = 1. */
2444 {
2445 /* Don't write &op0, etc., because that would prevent op0
2446 from being kept in a register.
2447 Instead, make copies of the our local variables and
2448 pass the copies by reference, then copy them back afterward. */
2451 tree val
2462 {
2474 /* Give warnings for comparisons between signed and unsigned
2475 quantities that may fail.
2477 Do the checking based on the original operand trees, so that
2478 casts will be considered, but default promotions won't be.
2480 Do not warn if the comparison is being done in a signed type,
2481 since the signed type will only be chosen if it can represent
2482 all the values of the unsigned type. */
2485 /* Do not warn if both operands are the same signedness. */
2488 else
2489 {
2494 else
2497 /* Do not warn if the signed quantity is an
2498 unsuffixed integer literal (or some static
2499 constant expression involving such literals or a
2500 conditional expression involving such literals)
2501 and it is non-negative. */
2504 /* Do not warn if the comparison is an equality operation,
2505 the unsigned quantity is an integral constant, and it
2506 would fit in the result if the result were signed. */
2509 && int_fits_type_p
2512 /* Do not warn if the unsigned quantity is an enumeration
2513 constant and its maximum value would fit in the result
2514 if the result were signed. */
2517 && int_fits_type_p
2521 else
2523 }
2525 /* Warn if two unsigned values are being compared in a size
2526 larger than their original size, and one (and only one) is the
2527 result of a `~' operator. This comparison will always fail.
2529 Also warn if one operand is a constant, and the constant
2530 does not have all bits set that are set in the ~ operand
2531 when it is extended. */
2535 {
2539 else
2544 {
2545 tree primop;
2550 {
2554 }
2555 else
2556 {
2560 }
2565 {
2569 }
2570 }
2577 }
2578 }
2579 }
2580 }
2582 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2583 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2584 Then the expression will be built.
2585 It will be given type FINAL_TYPE if that is nonzero;
2586 otherwise, it will be given type RESULT_TYPE. */
2589 {
2592 }
2595 {
2600 }
2605 {
2607 tree folded;
2615 }
2616 }
2617 \f
2619 /* Return true if `t' is known to be non-negative. */
2621 int
2623 tree t;
2624 {
2626 {
2629 /* Find the last statement in the chain, ignoring the final
2630 * scope statement */
2635 }
2637 }
2639 /* Return a tree for the difference of pointers OP0 and OP1.
2640 The resulting tree has type int. */
2642 static tree
2645 {
2654 {
2659 }
2661 /* If the conversion to ptrdiff_type does anything like widening or
2662 converting a partial to an integral mode, we get a convert_expression
2663 that is in the way to do any simplifications.
2664 (fold-const.c doesn't know that the extra bits won't be needed.
2665 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2666 different mode in place.)
2667 So first try to find a common term here 'by hand'; we want to cover
2668 at least the cases that occur in legal static initializers. */
2673 {
2676 }
2677 else
2681 {
2684 }
2685 else
2689 {
2692 }
2695 /* First do the subtraction as integers;
2696 then drop through to build the divide operator.
2697 Do not do default conversions on the minus operator
2698 in case restype is a short type. */
2702 /* This generates an error if op1 is pointer to incomplete type. */
2706 /* This generates an error if op0 is pointer to incomplete type. */
2709 /* Divide by the size, in easiest possible way. */
2717 }
2718 \f
2719 /* Construct and perhaps optimize a tree representation
2720 for a unary operation. CODE, a tree_code, specifies the operation
2721 and XARG is the operand.
2722 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2723 the default promotions (such as from short to int).
2724 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2725 allows non-lvalues; this is only used to handle conversion of non-lvalue
2726 arrays to pointers in C99. */
2728 tree
2731 tree xarg;
2733 {
2734 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2738 tree val;
2747 {
2749 /* This is used for unary plus, because a CONVERT_EXPR
2750 is enough to prevent anybody from looking inside for
2751 associativity, but won't generate any code. */
2754 {
2757 }
2767 {
2770 }
2777 {
2780 }
2782 {
2788 }
2789 else
2790 {
2793 }
2799 {
2802 }
2808 /* Conjugating a real value is a no-op, but allow it anyway. */
2811 {
2814 }
2823 /* These will convert to a pointer. */
2825 {
2828 }
2840 else
2848 else
2855 /* Handle complex lvalues (when permitted)
2856 by reduction to simpler cases. */
2862 /* Increment or decrement the real part of the value,
2863 and don't change the imaginary part. */
2865 {
2876 }
2878 /* Report invalid types. */
2882 {
2885 else
2889 }
2891 {
2892 tree inc;
2898 /* Compute the increment. */
2901 {
2902 /* If pointer target is an undefined struct,
2903 we just cannot know how to do the arithmetic. */
2905 {
2908 else
2910 }
2914 {
2917 else
2919 }
2922 }
2923 else
2928 /* Handle incrementing a cast-expression. */
2932 {
2941 /* If the real type has the same machine representation
2942 as the type it is cast to, we can make better output
2943 by adding directly to the inside of the cast. */
2949 else
2950 {
2954 else
2955 {
2959 else
2968 }
2971 }
2976 }
2977 give_up:
2979 /* Complain about anything else that is not a true lvalue. */
2986 /* Report a read-only lvalue. */
2995 else
3002 }
3005 /* Note that this operation never does default_conversion. */
3007 /* Let &* cancel out to simplify resulting code. */
3009 {
3010 /* Don't let this be an lvalue. */
3014 }
3016 /* For &x[y], return x+y */
3018 {
3023 }
3025 /* Handle complex lvalues (when permitted)
3026 by reduction to simpler cases. */
3032 float f; *&(int)f = 3.4 stores in int format
3033 whereas (int)f = 3.4 stores in float format. */
3034 /* Address of a cast is just a cast of the address
3035 of the operand of the cast. */
3037 {
3050 }
3051 #endif
3053 /* Anything not already handled and not a true memory reference
3054 or a non-lvalue array is an error. */
3059 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3062 /* If the lvalue is const or volatile, merge that into the type
3063 to which the address will point. Note that you can't get a
3064 restricted pointer by taking the address of something, so we
3065 only have to deal with `const' and `volatile' here. */
3077 {
3078 tree addr;
3081 {
3087 {
3091 }
3096 }
3097 else
3100 /* Address of a static or external variable or
3101 file-scope function counts as a constant. */
3107 }
3111 }
3116 }
3118 #if 0
3119 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3120 convert ARG with the same conversions in the same order
3121 and return the result. */
3123 static tree
3125 tree conversions;
3126 tree arg;
3127 {
3129 {
3139 arg));
3143 }
3144 }
3147 /* Return nonzero if REF is an lvalue valid for this language.
3148 Lvalues can be assigned, unless their type has TYPE_READONLY.
3149 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3151 int
3153 tree ref;
3154 {
3158 {
3183 }
3184 }
3186 /* Return nonzero if REF is an lvalue valid for this language;
3187 otherwise, print an error message and return zero. */
3189 int
3191 tree ref;
3193 {
3200 }
3202 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3203 for certain kinds of expressions which are not really lvalues
3204 but which we can accept as lvalues. If FLAG is nonzero, then
3205 non-lvalues are OK since we may be converting a non-lvalue array to
3206 a pointer in C99.
3208 If ARG is not a kind of expression we can handle, return zero. */
3210 static tree
3213 tree arg;
3215 {
3216 /* Handle (a, b) used as an "lvalue". */
3218 {
3221 /* If this returns a function type, it isn't really being used as
3222 an lvalue, so don't issue a warning about it. */
3228 }
3230 /* Handle (a ? b : c) used as an "lvalue". */
3232 {
3242 }
3245 }
3247 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3248 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3250 static void
3253 {
3256 {
3266 }
3267 }
3268 \f
3269 /* Warn about storing in something that is `const'. */
3271 void
3273 tree arg;
3275 {
3277 {
3280 else
3283 }
3287 else
3289 }
3290 \f
3291 /* Mark EXP saying that we need to be able to take the
3292 address of it; it should not be allocated in a register.
3293 Returns true if successful. */
3295 bool
3297 tree exp;
3298 {
3303 {
3306 {
3310 }
3312 /* ... fall through ... */
3332 {
3334 {
3338 }
3341 }
3343 {
3345 {
3349 }
3351 /* If we are making this addressable due to its having
3352 volatile components, give a different error message. Also
3353 handle the case of an unnamed parameter by not trying
3354 to give the name. */
3357 {
3360 }
3364 }
3367 /* drops in */
3373 #endif
3377 }
3378 }
3379 \f
3380 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3382 tree
3385 {
3386 tree type1;
3387 tree type2;
3396 /* Don't promote the operands separately if they promote
3397 the same way. Return the unpromoted type and let the combined
3398 value get promoted if necessary. */
3404 {
3409 }
3410 #endif
3412 /* Promote both alternatives. */
3429 /* Quickly detect the usual case where op1 and op2 have the same type
3430 after promotion. */
3432 {
3435 else
3437 }
3442 {
3445 /* If -Wsign-compare, warn here if type1 and type2 have
3446 different signedness. We'll promote the signed to unsigned
3447 and later code won't know it used to be different.
3448 Do this check on the original types, so that explicit casts
3449 will be considered, but default promotions won't. */
3451 {
3456 {
3457 /* Do not warn if the result type is signed, since the
3458 signed type will only be chosen if it can represent
3459 all the values of the unsigned type. */
3462 /* Do not warn if the signed quantity is an unsuffixed
3463 integer literal (or some static constant expression
3464 involving such literals) and it is non-negative. */
3468 else
3470 }
3471 }
3472 }
3474 {
3478 }
3480 {
3490 {
3495 }
3497 {
3502 }
3503 else
3504 {
3507 }
3508 }
3510 {
3513 else
3514 {
3516 }
3518 }
3520 {
3523 else
3524 {
3526 }
3528 }
3531 {
3534 else
3535 {
3538 }
3539 }
3541 /* Merge const and volatile flags of the incoming types. */
3542 result_type
3556 }
3557 \f
3558 /* Given a list of expressions, return a compound expression
3559 that performs them all and returns the value of the last of them. */
3561 tree
3563 tree list;
3564 {
3566 }
3568 static tree
3570 tree list;
3572 {
3573 tree rest;
3576 {
3577 /* Convert arrays and functions to pointers when there
3578 really is a comma operator. */
3584 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3586 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3589 #endif
3591 /* Don't let (0, 0) be null pointer constant. */
3595 }
3600 {
3601 /* The left-hand operand of a comma expression is like an expression
3602 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3603 any side-effects, unless it was explicitly cast to (void). */
3609 /* When pedantic, a compound expression can be neither an lvalue
3610 nor an integer constant expression. */
3613 }
3615 /* With -Wunused, we should also warn if the left-hand operand does have
3616 side-effects, but computes a value which is not used. For example, in
3617 `foo() + bar(), baz()' the result of the `+' operator is not used,
3618 so we should issue a warning. */
3623 }
3625 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3627 tree
3629 tree type;
3630 tree expr;
3631 {
3637 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3638 only in <protocol> qualifications. But when constructing cast expressions,
3639 the protocols do matter and must be kept around. */
3643 #if 0
3644 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3647 #endif
3650 {
3653 }
3656 {
3659 }
3662 {
3664 {
3668 }
3669 }
3671 {
3672 tree field;
3681 {
3682 tree t;
3692 }
3695 }
3696 else
3697 {
3700 /* If casting to void, avoid the error that would come
3701 from default_conversion in the case of a non-lvalue array. */
3705 /* Convert functions and arrays to pointers,
3706 but don't convert any other types. */
3710 /* Optionally warn about potentially worrisome casts. */
3715 {
3721 /* Check that the qualifiers on IN_TYPE are a superset of
3722 the qualifiers of IN_OTYPE. The outermost level of
3723 POINTER_TYPE nodes is uninteresting and we stop as soon
3724 as we hit a non-POINTER_TYPE node on either type. */
3725 do
3726 {
3730 /* GNU C allows cv-qualified function types. 'const'
3731 means the function is very pure, 'volatile' means it
3732 can't return. We need to warn when such qualifiers
3733 are added, not when they're taken away. */
3737 else
3739 }
3747 /* There are qualifiers present in IN_OTYPE that are not
3748 present in IN_TYPE. */
3750 }
3752 /* Warn about possible alignment problems. */
3758 /* Don't warn about opaque types, where the actual alignment
3759 restriction is unknown. */
3780 /* Don't warn about converting any constant. */
3790 {
3791 /* Casting the address of a decl to non void pointer. Warn
3792 if the cast breaks type based aliasing. */
3799 }
3802 /* Replace a nonvolatile const static variable with its value. */
3807 /* Ignore any integer overflow caused by the cast. */
3809 {
3812 }
3813 }
3815 /* Pedantically, don't let (void *) (FOO *) 0 be a null pointer constant. */
3821 /* If pedantic, don't let a cast be an lvalue. */
3826 }
3828 /* Interpret a cast of expression EXPR to type TYPE. */
3829 tree
3832 {
3835 /* This avoids warnings about unprototyped casts on
3836 integers. E.g. "#define SIG_DFL (void(*)())0". */
3843 }
3845 \f
3846 /* Build an assignment expression of lvalue LHS from value RHS.
3847 MODIFYCODE is the code for a binary operator that we use
3848 to combine the old value of LHS with RHS to get the new value.
3849 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3851 tree
3855 {
3856 tree result;
3857 tree newrhs;
3861 /* Types that aren't fully specified cannot be used in assignments. */
3864 /* Avoid duplicate error messages from operands that had errors. */
3868 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3869 /* Do not use STRIP_NOPS here. We do not want an enumerator
3870 whose value is 0 to count as a null pointer constant. */
3876 /* Handle control structure constructs used as "lvalues". */
3879 {
3880 /* Handle (a, b) used as an "lvalue". */
3889 /* Handle (a ? b : c) used as an "lvalue". */
3893 {
3894 /* Produce (a ? (b = rhs) : (c = rhs))
3895 except that the RHS goes through a save-expr
3896 so the code to compute it is only emitted once. */
3897 tree cond
3905 /* Make sure the code to compute the rhs comes out
3906 before the split. */
3908 /* But cast it to void to avoid an "unused" error. */
3910 }
3913 }
3915 /* If a binary op has been requested, combine the old LHS value with the RHS
3916 producing the value we should actually store into the LHS. */
3919 {
3922 }
3924 /* Handle a cast used as an "lvalue".
3925 We have already performed any binary operator using the value as cast.
3926 Now convert the result to the cast type of the lhs,
3927 and then true type of the lhs and store it there;
3928 then convert result back to the cast type to be the value
3929 of the assignment. */
3932 {
3941 {
3943 tree result;
3951 }
3955 }
3957 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3958 Reject anything strange now. */
3963 /* Warn about storing in something that is `const'. */
3971 /* If storing into a structure or union member,
3972 it has probably been given type `int'.
3973 Compute the type that would go with
3974 the actual amount of storage the member occupies. */
3983 /* If storing in a field that is in actuality a short or narrower than one,
3984 we must store in the field in its actual type. */
3987 {
3990 }
3992 /* Convert new value to destination type. */
3999 /* Scan operands */
4004 /* If we got the LHS in a different type for storing in,
4005 convert the result back to the nominal type of LHS
4006 so that the value we return always has the same type
4007 as the LHS argument. */
4013 }
4014 \f
4015 /* Convert value RHS to type TYPE as preparation for an assignment
4016 to an lvalue of type TYPE.
4017 The real work of conversion is done by `convert'.
4018 The purpose of this function is to generate error messages
4019 for assignments that are not allowed in C.
4020 ERRTYPE is a string to use in error messages:
4021 "assignment", "return", etc. If it is null, this is parameter passing
4022 for a function call (and different error messages are output).
4024 FUNNAME is the name of the function being called,
4025 as an IDENTIFIER_NODE, or null.
4026 PARMNUM is the number of the argument, for printing in error messages. */
4028 static tree
4034 {
4036 tree rhstype;
4039 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4040 /* Do not use STRIP_NOPS here. We do not want an enumerator
4041 whose value is 0 to count as a null pointer constant. */
4058 {
4060 /* Check for Objective-C protocols. This will automatically
4061 issue a warning if there are protocol violations. No need to
4062 use the return value. */
4066 }
4069 {
4072 }
4073 /* A type converts to a reference to it.
4074 This code doesn't fully support references, it's just for the
4075 special case of va_start and va_copy. */
4078 {
4080 {
4083 }
4088 /* We already know that these two types are compatible, but they
4089 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4090 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4091 likely to be va_list, a typedef to __builtin_va_list, which
4092 is different enough that it will cause problems later. */
4098 }
4099 /* Some types can interconvert without explicit casts. */
4104 /* Arithmetic types all interconvert, and enum is treated like int. */
4113 /* Conversion to a transparent union from its member types.
4114 This applies only to function arguments. */
4116 {
4117 tree memb_types;
4122 {
4133 {
4137 /* Any non-function converts to a [const][volatile] void *
4138 and vice versa; otherwise, targets must be the same.
4139 Meanwhile, the lhs target must have all the qualifiers of
4140 the rhs. */
4143 {
4144 /* If this type won't generate any warnings, use it. */
4154 /* Keep looking for a better type, but remember this one. */
4157 }
4158 }
4160 /* Can convert integer zero to any pointer type. */
4164 {
4167 }
4168 }
4171 {
4173 {
4174 /* We have only a marginally acceptable member type;
4175 it needs a warning. */
4179 /* Const and volatile mean something different for function
4180 types, so the usual warnings are not appropriate. */
4183 {
4184 /* Because const and volatile on functions are
4185 restrictions that say the function will not do
4186 certain things, it is okay to use a const or volatile
4187 function where an ordinary one is wanted, but not
4188 vice-versa. */
4192 }
4196 parmnum);
4197 }
4203 }
4204 }
4206 /* Conversions among pointers */
4209 {
4214 /* Opaque pointers are treated like void pointers. */
4220 /* Any non-function converts to a [const][volatile] void *
4221 and vice versa; otherwise, targets must be the same.
4222 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4225 || is_opaque_pointer
4228 {
4231 ||
4233 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4234 which are not ANSI null ptr constants. */
4239 /* Const and volatile mean something different for function types,
4240 so the usual warnings are not appropriate. */
4243 {
4247 /* If this is not a case of ignoring a mismatch in signedness,
4248 no warning. */
4251 ;
4252 /* If there is a mismatch, do warn. */
4256 }
4259 {
4260 /* Because const and volatile on functions are restrictions
4261 that say the function will not do certain things,
4262 it is okay to use a const or volatile function
4263 where an ordinary one is wanted, but not vice-versa. */
4267 }
4268 }
4269 else
4273 }
4275 {
4276 /* An explicit constant 0 can convert to a pointer,
4277 or one that results from arithmetic, even including
4278 a cast to integer type. */
4280 &&
4285 {
4289 }
4291 }
4293 {
4297 }
4302 {
4304 {
4310 else
4313 }
4314 else
4316 parmnum);
4317 }
4318 else
4322 }
4324 /* Convert VALUE for assignment into inlined parameter PARM. */
4326 tree
4329 {
4332 /* If FN was prototyped, the value has been converted already
4333 in convert_arguments. */
4346 }
4348 /* Print a warning using MSGID.
4349 It gets OPNAME as its one parameter.
4350 if OPNAME is null and ARGNUM is 0, it is replaced by "passing arg of `FUNCTION'".
4351 Otherwise if OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4352 FUNCTION and ARGNUM are handled specially if we are building an
4353 Objective-C selector. */
4355 static void
4359 tree function;
4361 {
4363 {
4368 {
4371 }
4373 {
4375 {
4376 /* Function name is known; supply it. */
4383 }
4384 else
4385 {
4386 /* Function name unknown (call through ptr). */
4390 }
4391 }
4393 {
4394 /* Function name is known; supply it. */
4401 }
4402 else
4403 {
4404 /* Function name unknown (call through ptr); just give arg number. */
4408 }
4410 }
4412 }
4413 \f
4414 /* If VALUE is a compound expr all of whose expressions are constant, then
4415 return its value. Otherwise, return error_mark_node.
4417 This is for handling COMPOUND_EXPRs as initializer elements
4418 which is allowed with a warning when -pedantic is specified. */
4420 static tree
4422 tree value;
4423 tree endtype;
4424 {
4426 {
4431 endtype);
4432 }
4436 else
4438 }
4439 \f
4440 /* Perform appropriate conversions on the initial value of a variable,
4441 store it in the declaration DECL,
4442 and print any error messages that are appropriate.
4443 If the init is invalid, store an ERROR_MARK. */
4445 void
4448 {
4451 /* If variable's type was invalidly declared, just ignore it. */
4457 /* Digest the specified initializer into an expression. */
4461 /* Store the expression if valid; else report error. */
4463 #if 0
4464 /* Note that this is the only place we can detect the error
4465 in a case such as struct foo bar = (struct foo) { x, y };
4466 where there is one initial value which is a constructor expression. */
4468 ;
4470 {
4473 }
4476 {
4479 }
4480 else
4481 {
4483 {
4488 }
4489 }
4490 #endif
4498 /* ANSI wants warnings about out-of-range constant initializers. */
4502 /* Check if we need to set array size from compound literal size. */
4506 {
4514 {
4518 {
4519 /* For int foo[] = (int [3]){1}; we need to set array size
4520 now since later on array initializer will be just the
4521 brace enclosed list of the compound literal. */
4525 }
4526 }
4527 }
4528 }
4529 \f
4530 /* Methods for storing and printing names for error messages. */
4532 /* Implement a spelling stack that allows components of a name to be pushed
4533 and popped. Each element on the stack is this structure. */
4535 struct spelling
4536 {
4538 union
4539 {
4543 };
4545 #define SPELLING_STRING 1
4546 #define SPELLING_MEMBER 2
4547 #define SPELLING_BOUNDS 3
4553 /* Macros to save and restore the spelling stack around push_... functions.
4554 Alternative to SAVE_SPELLING_STACK. */
4556 #define SPELLING_DEPTH() (spelling - spelling_base)
4557 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4559 /* Push an element on the spelling stack with type KIND and assign VALUE
4560 to MEMBER. */
4562 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4563 { \
4564 int depth = SPELLING_DEPTH (); \
4565 \
4566 if (depth >= spelling_size) \
4567 { \
4568 spelling_size += 10; \
4569 if (spelling_base == 0) \
4570 spelling_base \
4571 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4572 else \
4573 spelling_base \
4574 = (struct spelling *) xrealloc (spelling_base, \
4575 spelling_size * sizeof (struct spelling)); \
4576 RESTORE_SPELLING_DEPTH (depth); \
4577 } \
4578 \
4579 spelling->kind = (KIND); \
4580 spelling->MEMBER = (VALUE); \
4581 spelling++; \
4582 }
4584 /* Push STRING on the stack. Printed literally. */
4586 static void
4589 {
4591 }
4593 /* Push a member name on the stack. Printed as '.' STRING. */
4595 static void
4597 tree decl;
4599 {
4603 }
4605 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4607 static void
4610 {
4612 }
4614 /* Compute the maximum size in bytes of the printed spelling. */
4616 static int
4618 {
4623 {
4626 else
4628 }
4631 }
4633 /* Print the spelling to BUFFER and return it. */
4638 {
4644 {
4647 }
4648 else
4649 {
4654 ;
4655 }
4658 }
4660 /* Issue an error message for a bad initializer component.
4661 MSGID identifies the message.
4662 The component name is taken from the spelling stack. */
4664 void
4667 {
4674 }
4676 /* Issue a pedantic warning for a bad initializer component.
4677 MSGID identifies the message.
4678 The component name is taken from the spelling stack. */
4680 void
4683 {
4690 }
4692 /* Issue a warning for a bad initializer component.
4693 MSGID identifies the message.
4694 The component name is taken from the spelling stack. */
4696 static void
4699 {
4706 }
4707 \f
4708 /* Digest the parser output INIT as an initializer for type TYPE.
4709 Return a C expression of type TYPE to represent the initial value.
4711 REQUIRE_CONSTANT requests an error if non-constant initializers or
4712 elements are seen. */
4714 static tree
4718 {
4727 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4728 /* Do not use STRIP_NOPS here. We do not want an enumerator
4729 whose value is 0 to count as a null pointer constant. */
4735 /* Initialization of an array of chars from a string constant
4736 optionally enclosed in braces. */
4739 {
4747 {
4755 {
4758 }
4762 {
4765 }
4771 /* Subtract 1 (or sizeof (wchar_t))
4772 because it's ok to ignore the terminating null char
4773 that is counted in the length of the constant. */
4784 }
4785 }
4787 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4788 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4789 below and handle as a constructor. */
4793 {
4798 else
4800 }
4802 /* Any type can be initialized
4803 from an expression of the same type, optionally with braces. */
4817 {
4823 {
4824 /* As an extension, allow initializing objects with static storage
4825 duration with compound literals (which are then treated just as
4826 the brace enclosed list they contain). */
4829 }
4833 {
4836 }
4841 /* Compound expressions can only occur here if -pedantic or
4842 -pedantic-errors is specified. In the later case, we always want
4843 an error. In the former case, we simply want a warning. */
4846 {
4847 inside_init
4852 else
4856 }
4859 /* This test catches things like `7 / 0' which
4860 result in an expression for which TREE_CONSTANT
4861 is true, but which is not actually something
4862 that is a legal constant. We really should not
4863 be using this function, because it is a part of
4864 the back-end. Instead, the expression should
4865 already have been turned into ERROR_MARK_NODE. */
4868 {
4871 }
4874 }
4876 /* Handle scalar types, including conversions. */
4880 {
4881 /* Note that convert_for_assignment calls default_conversion
4882 for arrays and functions. We must not call it in the
4883 case where inside_init is a null pointer constant. */
4884 inside_init
4889 {
4892 }
4895 {
4898 }
4901 }
4903 /* Come here only for records and arrays. */
4906 {
4909 }
4913 }
4914 \f
4915 /* Handle initializers that use braces. */
4917 /* Type of object we are accumulating a constructor for.
4918 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4921 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4922 left to fill. */
4925 /* For an ARRAY_TYPE, this is the specified index
4926 at which to store the next element we get. */
4929 /* For an ARRAY_TYPE, this is the maximum index. */
4932 /* For a RECORD_TYPE, this is the first field not yet written out. */
4935 /* For an ARRAY_TYPE, this is the index of the first element
4936 not yet written out. */
4939 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4940 This is so we can generate gaps between fields, when appropriate. */
4943 /* If we are saving up the elements rather than allocating them,
4944 this is the list of elements so far (in reverse order,
4945 most recent first). */
4948 /* 1 if constructor should be incrementally stored into a constructor chain,
4949 0 if all the elements should be kept in AVL tree. */
4952 /* 1 if so far this constructor's elements are all compile-time constants. */
4955 /* 1 if so far this constructor's elements are all valid address constants. */
4958 /* 1 if this constructor is erroneous so far. */
4961 /* Structure for managing pending initializer elements, organized as an
4962 AVL tree. */
4964 struct init_node
4965 {
4969 tree purpose;
4970 tree value;
4971 };
4973 /* Tree of pending elements at this constructor level.
4974 These are elements encountered out of order
4975 which belong at places we haven't reached yet in actually
4976 writing the output.
4977 Will never hold tree nodes across GC runs. */
4980 /* The SPELLING_DEPTH of this constructor. */
4983 /* 0 if implicitly pushing constructor levels is allowed. */
4989 /* DECL node for which an initializer is being read.
4990 0 means we are reading a constructor expression
4991 such as (struct foo) {...}. */
4994 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4997 /* Nonzero if this is an initializer for a top-level decl. */
5000 /* Nonzero if there were any member designators in this initializer. */
5003 /* Nesting depth of designator list. */
5006 /* Nonzero if there were diagnosed errors in this designator list. */
5009 \f
5010 /* This stack has a level for each implicit or explicit level of
5011 structuring in the initializer, including the outermost one. It
5012 saves the values of most of the variables above. */
5016 struct constructor_stack
5017 {
5019 tree type;
5020 tree fields;
5021 tree index;
5022 tree max_index;
5023 tree unfilled_index;
5024 tree unfilled_fields;
5025 tree bit_index;
5026 tree elements;
5030 /* If nonzero, this value should replace the entire
5031 constructor at this level. */
5032 tree replacement_value;
5041 };
5045 /* This stack represents designators from some range designator up to
5046 the last designator in the list. */
5048 struct constructor_range_stack
5049 {
5052 tree range_start;
5053 tree index;
5054 tree range_end;
5055 tree fields;
5056 };
5060 /* This stack records separate initializers that are nested.
5061 Nested initializers can't happen in ANSI C, but GNU C allows them
5062 in cases like { ... (struct foo) { ... } ... }. */
5064 struct initializer_stack
5065 {
5067 tree decl;
5071 tree elements;
5078 };
5081 \f
5082 /* Prepare to parse and output the initializer for variable DECL. */
5084 void
5086 tree decl;
5087 tree asmspec_tree;
5089 {
5118 {
5120 require_constant_elements
5122 /* For a scalar, you can always use any value to initialize,
5123 even within braces. */
5129 }
5130 else
5131 {
5135 }
5148 }
5150 void
5152 {
5155 /* Free the whole constructor stack of this initializer. */
5157 {
5161 }
5166 /* Pop back to the data of the outer initializer (if any). */
5180 }
5181 \f
5182 /* Call here when we see the initializer is surrounded by braces.
5183 This is instead of a call to push_init_level;
5184 it is matched by a call to pop_init_level.
5186 TYPE is the type to initialize, for a constructor expression.
5187 For an initializer for a decl, TYPE is zero. */
5189 void
5191 tree type;
5192 {
5237 {
5239 /* Skip any nameless bit fields at the beginning. */
5246 }
5248 {
5250 {
5251 constructor_max_index
5254 /* Detect non-empty initializations of zero-length arrays. */
5259 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5260 to initialize VLAs will cause a proper error; avoid tree
5261 checking errors as well by setting a safe value. */
5266 constructor_index
5269 }
5270 else
5274 }
5276 {
5277 /* Vectors are like simple fixed-size arrays. */
5278 constructor_max_index =
5282 }
5283 else
5284 {
5285 /* Handle the case of int x = {5}; */
5288 }
5289 }
5290 \f
5291 /* Push down into a subobject, for initialization.
5292 If this is for an explicit set of braces, IMPLICIT is 0.
5293 If it is because the next element belongs at a lower level,
5294 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5296 void
5299 {
5303 /* If we've exhausted any levels that didn't have braces,
5304 pop them now. */
5306 {
5312 && constructor_max_index
5315 else
5317 }
5319 /* Unless this is an explicit brace, we need to preserve previous
5320 content if any. */
5322 {
5329 }
5362 {
5367 }
5369 /* Don't die if an entire brace-pair level is superfluous
5370 in the containing level. */
5372 ;
5375 {
5376 /* Don't die if there are extra init elts at the end. */
5379 else
5380 {
5383 constructor_depth++;
5384 }
5385 }
5387 {
5390 constructor_depth++;
5391 }
5394 {
5399 }
5402 {
5410 }
5413 {
5416 }
5420 {
5422 /* Skip any nameless bit fields at the beginning. */
5429 }
5431 {
5432 /* Vectors are like simple fixed-size arrays. */
5433 constructor_max_index =
5437 }
5439 {
5441 {
5442 constructor_max_index
5445 /* Detect non-empty initializations of zero-length arrays. */
5450 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5451 to initialize VLAs will cause a proper error; avoid tree
5452 checking errors as well by setting a safe value. */
5457 constructor_index
5460 }
5461 else
5466 {
5467 /* We need to split the char/wchar array into individual
5468 characters, so that we don't have to special case it
5469 everywhere. */
5471 }
5472 }
5473 else
5474 {
5478 }
5479 }
5481 /* At the end of an implicit or explicit brace level,
5482 finish up that level of constructor.
5483 If we were outputting the elements as they are read, return 0
5484 from inner levels (process_init_element ignores that),
5485 but return error_mark_node from the outermost level
5486 (that's what we want to put in DECL_INITIAL).
5487 Otherwise, return a CONSTRUCTOR expression. */
5489 tree
5492 {
5497 {
5498 /* When we come to an explicit close brace,
5499 pop any inner levels that didn't have explicit braces. */
5505 }
5509 /* Error for initializing a flexible array member, or a zero-length
5510 array member in an inappropriate context. */
5515 {
5516 /* Silently discard empty initializations. The parser will
5517 already have pedwarned for empty brackets. */
5521 {
5527 /* We have already issued an error message for the existence
5528 of a flexible array member not at the end of the structure.
5529 Discard the initializer so that we do not abort later. */
5532 }
5533 else
5534 /* Zero-length arrays are no longer special, so we should no longer
5535 get here. */
5537 }
5539 /* Warn when some struct elements are implicitly initialized to zero. */
5541 && constructor_type
5544 {
5545 /* Do not warn for flexible array members or zero-length arrays. */
5551 /* Do not warn if this level of the initializer uses member
5552 designators; it is likely to be deliberate. */
5554 {
5558 }
5559 }
5561 /* Now output all pending elements. */
5565 /* Pad out the end of the structure. */
5567 /* If this closes a superfluous brace pair,
5568 just pass out the element between them. */
5571 ;
5576 {
5577 /* A nonincremental scalar initializer--just return
5578 the element, after verifying there is just one. */
5580 {
5584 }
5586 {
5589 }
5590 else
5592 }
5593 else
5594 {
5597 else
5598 {
5605 }
5606 }
5631 {
5635 }
5637 }
5639 /* Common handling for both array range and field name designators.
5640 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5642 static int
5645 {
5646 tree subtype;
5649 /* Don't die if an entire brace-pair level is superfluous
5650 in the containing level. */
5654 /* If there were errors in this designator list already, bail out silently. */
5659 {
5663 /* Designator list starts at the level of closest explicit
5664 braces. */
5669 }
5672 {
5675 }
5679 {
5683 }
5685 {
5687 }
5688 else
5693 {
5696 }
5698 {
5701 }
5706 }
5708 /* If there are range designators in designator list, push a new designator
5709 to constructor_range_stack. RANGE_END is end of such stack range or
5710 NULL_TREE if there is no range designator at this level. */
5712 static void
5714 tree range_end;
5715 {
5730 }
5732 /* Within an array initializer, specify the next index to be initialized.
5733 FIRST is that index. If LAST is nonzero, then initialize a range
5734 of indices, running from FIRST through LAST. */
5736 void
5739 {
5769 else
5770 {
5774 {
5778 {
5781 }
5782 else
5783 {
5787 {
5790 }
5791 }
5792 }
5794 designator_depth++;
5798 }
5799 }
5801 /* Within a struct initializer, specify the next field to be initialized. */
5803 void
5805 tree fieldname;
5806 {
5807 tree tail;
5816 {
5819 }
5823 {
5826 }
5831 else
5832 {
5834 designator_depth++;
5838 }
5839 }
5840 \f
5841 /* Add a new initializer to the tree of pending initializers. PURPOSE
5842 identifies the initializer, either array index or field in a structure.
5843 VALUE is the value of that index or field. */
5845 static void
5848 {
5855 {
5857 {
5863 else
5864 {
5869 }
5870 }
5871 }
5872 else
5873 {
5874 tree bitpos;
5878 {
5884 else
5885 {
5890 }
5891 }
5892 }
5905 {
5909 {
5913 {
5915 {
5916 /* L rotation. */
5929 {
5932 else
5934 }
5935 else
5937 }
5938 else
5939 {
5940 /* LR rotation. */
5962 {
5965 else
5967 }
5968 else
5970 }
5972 }
5973 else
5974 {
5975 /* p->balance == +1; growth of left side balances the node. */
5978 }
5979 }
5981 {
5983 /* Growth propagation from right side. */
5986 {
5988 {
5989 /* R rotation. */
6002 {
6005 else
6007 }
6008 else
6010 }
6012 {
6013 /* RL rotation */
6035 {
6038 else
6040 }
6041 else
6043 }
6045 }
6046 else
6047 {
6048 /* p->balance == -1; growth of right side balances the node. */
6051 }
6052 }
6056 }
6057 }
6059 /* Build AVL tree from a sorted chain. */
6061 static void
6063 {
6064 tree chain;
6074 {
6076 /* Skip any nameless bit fields at the beginning. */
6082 }
6084 {
6086 constructor_unfilled_index
6089 else
6091 }
6093 }
6095 /* Build AVL tree from a string constant. */
6097 static void
6099 tree str;
6100 {
6115 else
6126 {
6128 {
6131 }
6132 else
6133 {
6137 {
6140 else
6145 }
6146 }
6149 {
6152 {
6154 {
6157 }
6158 }
6160 {
6163 }
6168 }
6173 }
6176 }
6178 /* Return value of FIELD in pending initializer or zero if the field was
6179 not initialized yet. */
6181 static tree
6183 tree field;
6184 {
6188 {
6195 {
6200 else
6202 }
6203 }
6205 {
6209 && (!constructor_unfilled_fields
6216 {
6221 else
6223 }
6224 }
6226 {
6230 }
6232 }
6234 /* "Output" the next constructor element.
6235 At top level, really output it to assembler code now.
6236 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6237 TYPE is the data type that the containing data type wants here.
6238 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6240 PENDING if non-nil means output pending elements that belong
6241 right after this element. (PENDING is normally 1;
6242 it is 0 while outputting pending elements, to avoid recursion.) */
6244 static void
6248 {
6250 {
6253 }
6265 {
6266 /* As an extension, allow initializing objects with static storage
6267 duration with compound literals (which are then treated just as
6268 the brace enclosed list they contain). */
6271 }
6285 {
6288 }
6293 /* If this field is empty (and not at the end of structure),
6294 don't do anything other than checking the initializer. */
6305 {
6308 }
6310 /* If this element doesn't come next in sequence,
6311 put it on constructor_pending_elts. */
6313 && (!constructor_incremental
6315 {
6322 }
6324 && (!constructor_incremental
6326 {
6327 /* We do this for records but not for unions. In a union,
6328 no matter which field is specified, it can be initialized
6329 right away since it starts at the beginning of the union. */
6331 {
6334 else
6335 {
6343 }
6344 }
6348 }
6351 {
6355 /* We can have just one union field set. */
6357 }
6359 /* Otherwise, output this element either to
6360 constructor_elements or to the assembler file. */
6364 constructor_elements
6367 /* Advance the variable that indicates sequential elements output. */
6369 constructor_unfilled_index
6371 bitsize_one_node);
6373 {
6374 constructor_unfilled_fields
6377 /* Skip any nameless bit fields. */
6381 constructor_unfilled_fields =
6383 }
6387 /* Now output any pending elements which have become next. */
6390 }
6392 /* Output any pending elements which have become next.
6393 As we output elements, constructor_unfilled_{fields,index}
6394 advances, which may cause other elements to become next;
6395 if so, they too are output.
6397 If ALL is 0, we return when there are
6398 no more pending elements to output now.
6400 If ALL is 1, we output space as necessary so that
6401 we can output all the pending elements. */
6403 static void
6406 {
6408 tree next;
6410 retry:
6412 /* Look thru the whole pending tree.
6413 If we find an element that should be output now,
6414 output it. Otherwise, set NEXT to the element
6415 that comes first among those still pending. */
6419 {
6421 {
6423 constructor_unfilled_index))
6429 {
6430 /* Advance to the next smaller node. */
6433 else
6434 {
6435 /* We have reached the smallest node bigger than the
6436 current unfilled index. Fill the space first. */
6439 }
6440 }
6441 else
6442 {
6443 /* Advance to the next bigger node. */
6446 else
6447 {
6448 /* We have reached the biggest node in a subtree. Find
6449 the parent of it, which is the next bigger node. */
6455 {
6458 }
6459 }
6460 }
6461 }
6464 {
6467 /* If the current record is complete we are done. */
6473 /* We can't compare fields here because there might be empty
6474 fields in between. */
6476 {
6480 }
6482 {
6483 /* Advance to the next smaller node. */
6486 else
6487 {
6488 /* We have reached the smallest node bigger than the
6489 current unfilled field. Fill the space first. */
6492 }
6493 }
6494 else
6495 {
6496 /* Advance to the next bigger node. */
6499 else
6500 {
6501 /* We have reached the biggest node in a subtree. Find
6502 the parent of it, which is the next bigger node. */
6509 {
6512 }
6513 }
6514 }
6515 }
6516 }
6518 /* Ordinarily return, but not if we want to output all
6519 and there are elements left. */
6523 /* If it's not incremental, just skip over the gap, so that after
6524 jumping to retry we will output the next successive element. */
6531 /* ELT now points to the node in the pending tree with the next
6532 initializer to output. */
6534 }
6535 \f
6536 /* Add one non-braced element to the current constructor level.
6537 This adjusts the current position within the constructor's type.
6538 This may also start or terminate implicit levels
6539 to handle a partly-braced initializer.
6541 Once this has found the correct level for the new element,
6542 it calls output_init_element. */
6544 void
6546 tree value;
6547 {
6554 /* Handle superfluous braces around string cst as in
6555 char x[] = {"foo"}; */
6557 && constructor_type
6561 {
6566 }
6569 {
6572 }
6574 /* Ignore elements of a brace group if it is entirely superfluous
6575 and has already been diagnosed. */
6579 /* If we've exhausted any levels that didn't have braces,
6580 pop them now. */
6582 {
6590 constructor_index)))
6592 else
6594 }
6596 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6598 {
6599 /* If value is a compound literal and we'll be just using its
6600 content, don't put it into a SAVE_EXPR. */
6602 || !require_constant_value
6605 }
6608 {
6610 {
6611 tree fieldtype;
6615 {
6618 }
6625 /* Error for non-static initialization of a flexible array member. */
6627 && !require_constant_value
6630 {
6633 }
6635 /* Accept a string constant to initialize a subarray. */
6641 /* Otherwise, if we have come to a subaggregate,
6642 and we don't have an element of its type, push into it. */
6648 {
6651 }
6654 {
6658 }
6659 else
6660 /* Do the bookkeeping for an element that was
6661 directly output as a constructor. */
6662 {
6663 /* For a record, keep track of end position of last field. */
6665 constructor_bit_index
6670 /* If the current field was the first one not yet written out,
6671 it isn't now, so update. */
6673 {
6675 /* Skip any nameless bit fields. */
6679 constructor_unfilled_fields =
6681 }
6682 }
6685 /* Skip any nameless bit fields at the beginning. */
6690 }
6692 {
6693 tree fieldtype;
6697 {
6700 }
6707 /* Warn that traditional C rejects initialization of unions.
6708 We skip the warning if the value is zero. This is done
6709 under the assumption that the zero initializer in user
6710 code appears conditioned on e.g. __STDC__ to avoid
6711 "missing initializer" warnings and relies on default
6712 initialization to zero in the traditional C case.
6713 We also skip the warning if the initializer is designated,
6714 again on the assumption that this must be conditional on
6715 __STDC__ anyway (and we've already complained about the
6716 member-designator already). */
6721 /* Accept a string constant to initialize a subarray. */
6727 /* Otherwise, if we have come to a subaggregate,
6728 and we don't have an element of its type, push into it. */
6734 {
6737 }
6740 {
6744 }
6745 else
6746 /* Do the bookkeeping for an element that was
6747 directly output as a constructor. */
6748 {
6751 }
6754 }
6756 {
6760 /* Accept a string constant to initialize a subarray. */
6766 /* Otherwise, if we have come to a subaggregate,
6767 and we don't have an element of its type, push into it. */
6773 {
6776 }
6781 {
6784 }
6786 /* Now output the actual element. */
6788 {
6792 }
6794 constructor_index
6798 /* If we are doing the bookkeeping for an element that was
6799 directly output as a constructor, we must update
6800 constructor_unfilled_index. */
6802 }
6804 {
6807 /* Do a basic check of initializer size. Note that vectors
6808 always have a fixed size derived from their type. */
6810 {
6813 }
6815 /* Now output the actual element. */
6819 constructor_index
6823 /* If we are doing the bookkeeping for an element that was
6824 directly output as a constructor, we must update
6825 constructor_unfilled_index. */
6827 }
6829 /* Handle the sole element allowed in a braced initializer
6830 for a scalar variable. */
6832 {
6835 }
6836 else
6837 {
6841 }
6843 /* Handle range initializers either at this level or anywhere higher
6844 in the designator stack. */
6846 {
6853 {
6857 }
6861 {
6865 }
6872 {
6876 {
6879 }
6887 }
6892 }
6895 }
6898 }
6899 \f
6900 /* Build a simple asm-statement, from one string literal. */
6901 tree
6903 tree expr;
6904 {
6911 {
6912 tree stmt;
6914 /* Simple asm statements are treated as volatile. */
6919 }
6923 }
6925 /* Build an asm-statement, whose components are a CV_QUALIFIER, a
6926 STRING, some OUTPUTS, some INPUTS, and some CLOBBERS. */
6928 tree
6930 tree cv_qualifier;
6931 tree string;
6932 tree outputs;
6933 tree inputs;
6934 tree clobbers;
6935 {
6936 tree tail;
6939 {
6942 }
6946 {
6950 }
6952 /* We can remove output conversions that change the type,
6953 but not the mode. */
6955 {
6961 /* Allow conversions as LHS here. build_modify_expr as called below
6962 will do the right thing with them. */
6973 }
6975 /* Remove output conversions that change the type but not the mode. */
6977 {
6981 }
6983 /* Perform default conversions on array and function inputs.
6984 Don't do this for other types as it would screw up operands
6985 expected to be in memory. */
6991 }
6993 /* Expand an ASM statement with operands, handling output operands
6994 that are not variables or INDIRECT_REFS by transforming such
6995 cases into cases that expand_asm_operands can handle.
6997 Arguments are same as for expand_asm_operands. */
6999 void
7005 {
7008 /* o[I] is the place that output number I should be written. */
7010 tree tail;
7012 /* Record the contents of OUTPUTS before it is modified. */
7014 {
7018 }
7020 /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of
7021 OUTPUTS some trees for where the values were actually stored. */
7024 /* Copy all the intermediate outputs into the specified outputs. */
7026 {
7028 {
7033 /* Restore the original value so that it's correct the next
7034 time we expand this function. */
7036 }
7037 /* Detect modification of read-only values.
7038 (Otherwise done by build_modify_expr.) */
7039 else
7040 {
7048 }
7049 }
7051 /* Those MODIFY_EXPRs could do autoincrements. */
7053 }
7054 \f
7055 /* Expand a C `return' statement.
7056 RETVAL is the expression for what to return,
7057 or a null pointer for `return;' with no value. */
7059 tree
7061 tree retval;
7062 {
7069 {
7074 }
7076 {
7080 }
7081 else
7082 {
7086 tree inner;
7094 /* Strip any conversions, additions, and subtractions, and see if
7095 we are returning the address of a local variable. Warn if so. */
7097 {
7099 {
7106 /* If the second operand of the MINUS_EXPR has a pointer
7107 type (or is converted from it), this may be valid, so
7108 don't give a warning. */
7109 {
7123 }
7140 }
7143 }
7146 }
7149 }
7150 \f
7152 /* The SWITCH_STMT being built. */
7153 tree switch_stmt;
7154 /* A splay-tree mapping the low element of a case range to the high
7155 element, or NULL_TREE if there is no high element. Used to
7156 determine whether or not a new case label duplicates an old case
7157 label. We need a tree, rather than simply a hash table, because
7158 of the GNU case range extension. */
7159 splay_tree cases;
7160 /* The next node on the stack. */
7162 };
7164 /* A stack of the currently active switch statements. The innermost
7165 switch statement is on the top of the stack. There is no need to
7166 mark the stack for garbage collection because it is only active
7167 during the processing of the body of a function, and we never
7168 collect at that point. */
7172 /* Start a C switch statement, testing expression EXP. Return the new
7173 SWITCH_STMT. */
7175 tree
7177 tree exp;
7178 {
7184 {
7190 {
7193 }
7194 else
7195 {
7205 }
7206 }
7208 /* Add this new SWITCH_STMT to the stack. */
7216 }
7218 /* Process a case label. */
7220 tree
7222 tree low_value;
7223 tree high_value;
7224 {
7228 {
7237 {
7238 /* Attach the first case label to the SWITCH_BODY. */
7241 }
7242 }
7245 else
7249 }
7251 /* Finish the switch statement. */
7253 void
7255 {
7258 /* Rechain the next statements to the SWITCH_STMT. */
7261 /* Pop the stack. */
7265 }