| blob | b5bc210dab47207f61604b2213f9152bf88ad41a |
1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
23 /* This file is part of the C front end.
24 It contains routines to build C expressions given their operands,
25 including computing the types of the result, C-specific error checks,
26 and some optimization.
28 There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
29 and to process initializations in declarations (since they work
30 like a strange sort of assignment). */
46 /* Nonzero if we've already printed a "missing braces around initializer"
47 message within this initializer. */
50 /* 1 if we explained undeclared var errors. */
85 \f
86 /* Do `exp = require_complete_type (exp);' to make sure exp
87 does not have an incomplete type. (That includes void types.) */
89 tree
91 tree value;
92 {
98 /* First, detect a valid value with a complete type. */
104 }
106 /* Print an error message for invalid use of an incomplete type.
107 VALUE is the expression that was used (or 0 if that isn't known)
108 and TYPE is the type that was invalid. */
110 void
112 tree value;
113 tree type;
114 {
117 /* Avoid duplicate error message. */
125 else
126 {
127 retry:
128 /* We must print an error message. Be clever about what it says. */
131 {
150 {
152 {
155 }
158 }
164 }
169 else
170 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
173 }
174 }
176 /* Given a type, apply default promotions wrt unnamed function
177 arguments and return the new type. */
179 tree
181 tree type;
182 {
187 {
188 /* Preserve unsignedness if not really getting any wider. */
193 }
196 }
198 /* Return a variant of TYPE which has all the type qualifiers of LIKE
199 as well as those of TYPE. */
201 static tree
204 {
207 }
208 \f
209 /* Return the common type of two types.
210 We assume that comptypes has already been done and returned 1;
211 if that isn't so, this may crash. In particular, we assume that qualifiers
212 match.
214 This is the type for the result of most arithmetic operations
215 if the operands have the given two types. */
217 tree
220 {
223 tree attributes;
225 /* Save time if the two types are the same. */
229 /* If one type is nonsense, use the other. */
235 /* Merge the attributes. */
238 /* Treat an enum type as the unsigned integer type of the same width. */
248 /* If one type is complex, form the common type of the non-complex
249 components, then make that complex. Use T1 or T2 if it is the
250 required type. */
252 {
261 else
263 attributes);
264 }
267 {
270 /* If only one is real, use it as the result. */
278 /* Both real or both integers; use the one with greater precision. */
285 /* Same precision. Prefer longs to ints even when same size. */
290 attributes);
294 {
295 /* But preserve unsignedness from the other type,
296 since long cannot hold all the values of an unsigned int. */
299 else
302 }
304 /* Likewise, prefer long double to double even if same size. */
308 attributes);
310 /* Otherwise prefer the unsigned one. */
314 else
318 /* For two pointers, do this recursively on the target type,
319 and combine the qualifiers of the two types' targets. */
320 /* This code was turned off; I don't know why.
321 But ANSI C specifies doing this with the qualifiers.
322 So I turned it on again. */
323 {
333 }
334 #if 0
337 #endif
340 {
342 /* Save space: see if the result is identical to one of the args. */
347 /* Merge the element types, and have a size if either arg has one. */
350 }
353 /* Function types: prefer the one that specified arg types.
354 If both do, merge the arg types. Also merge the return types. */
355 {
363 /* Save space: see if the result is identical to one of the args. */
369 /* Simple way if one arg fails to specify argument types. */
371 {
374 }
376 {
379 }
381 /* If both args specify argument types, we must merge the two
382 lists, argument by argument. */
397 {
398 /* A null type means arg type is not specified.
399 Take whatever the other function type has. */
401 {
404 }
406 {
409 }
411 /* Given wait (union {union wait *u; int *i} *)
412 and wait (union wait *),
413 prefer union wait * as type of parm. */
416 {
417 tree memb;
421 {
426 }
427 }
430 {
431 tree memb;
435 {
440 }
441 }
443 parm_done: ;
444 }
449 /* ... falls through ... */
450 }
454 }
456 }
457 \f
458 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
459 or various other operations. Return 2 if they are compatible
460 but a warning may be needed if you use them together. */
462 int
465 {
470 /* Suppress errors caused by previously reported errors. */
476 /* If either type is the internal version of sizetype, return the
477 language version. */
486 /* Treat an enum type as the integer type of the same width and
487 signedness. */
497 /* Different classes of types can't be compatible. */
501 /* Qualifiers must match. */
506 /* Allow for two different type nodes which have essentially the same
507 definition. Note that we already checked for equality of the type
508 qualifiers (just above). */
513 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
517 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
521 {
532 {
539 /* Target types must match incl. qualifiers. */
544 /* Sizes must match unless one is missing or variable. */
551 d1_variable = (! d1_zero
554 d2_variable = (! d2_zero
568 }
577 }
579 }
581 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
582 ignoring their qualifiers. REFLEXIVE is only used by ObjC - set it
583 to 1 or 0 depending if the check of the pointer types is meant to
584 be reflexive or not (typically, assignments are not reflexive,
585 while comparisons are reflexive).
586 */
588 static int
592 {
595 /* Give objc_comptypes a crack at letting these types through. */
605 }
606 \f
607 /* Subroutines of `comptypes'. */
609 /* Return 1 if two function types F1 and F2 are compatible.
610 If either type specifies no argument types,
611 the other must specify a fixed number of self-promoting arg types.
612 Otherwise, if one type specifies only the number of arguments,
613 the other must specify that number of self-promoting arg types.
614 Otherwise, the argument types must match. */
616 static int
619 {
621 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
632 /* An unspecified parmlist matches any specified parmlist
633 whose argument types don't need default promotions. */
636 {
639 /* If one of these types comes from a non-prototype fn definition,
640 compare that with the other type's arglist.
641 If they don't match, ask for a warning (but no error). */
646 }
648 {
655 }
657 /* Both types have argument lists: compare them and propagate results. */
660 }
662 /* Check two lists of types for compatibility,
663 returning 0 for incompatible, 1 for compatible,
664 or 2 for compatible with warning. */
666 static int
669 {
670 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
675 {
678 /* If one list is shorter than the other,
679 they fail to match. */
682 /* A null pointer instead of a type
683 means there is supposed to be an argument
684 but nothing is specified about what type it has.
685 So match anything that self-promotes. */
687 {
690 }
692 {
695 }
698 {
699 /* Allow wait (union {union wait *u; int *i} *)
700 and wait (union wait *) to be compatible. */
707 {
708 tree memb;
715 }
722 {
723 tree memb;
730 }
731 else
733 }
735 /* comptypes said ok, but record if it said to warn. */
741 }
742 }
743 \f
744 /* Compute the size to increment a pointer by. */
746 tree
748 tree type;
749 {
756 {
759 }
761 /* Convert in case a char is more than one unit. */
765 }
766 \f
767 /* Return either DECL or its known constant value (if it has one). */
769 tree
771 tree decl;
772 {
774 in a place where a variable is invalid. */
780 /* This is invalid if initial value is not constant.
781 If it has either a function call, a memory reference,
782 or a variable, then re-evaluating it could give different results. */
784 /* Check for cases where this is sub-optimal, even though valid. */
788 }
790 /* Return either DECL or its known constant value (if it has one), but
791 return DECL if pedantic or DECL has mode BLKmode. This is for
792 bug-compatibility with the old behavior of decl_constant_value
793 (before GCC 3.0); every use of this function is a bug and it should
794 be removed before GCC 3.1. It is not appropriate to use pedantic
795 in a way that affects optimization, and BLKmode is probably not the
796 right test for avoiding misoptimizations either. */
798 static tree
800 tree decl;
801 {
804 else
806 }
809 /* Perform the default conversion of arrays and functions to pointers.
810 Return the result of converting EXP. For any other expression, just
811 return EXP. */
813 static tree
815 tree exp;
816 {
817 tree orig_exp;
822 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
823 an lvalue.
825 Do not use STRIP_NOPS here! It will remove conversions from pointer
826 to integer and cause infinite recursion. */
831 {
835 }
837 /* Preserve the original expression code. */
842 {
844 }
846 {
847 tree adr;
849 tree ptrtype;
855 {
858 }
861 restype
872 {
876 }
880 {
881 /* Before C99, non-lvalue arrays do not decay to pointers.
882 Normally, using such an array would be invalid; but it can
883 be used correctly inside sizeof or as a statement expression.
884 Thus, do not give an error here; an error will result later. */
886 }
891 {
892 /* ??? This is not really quite correct
893 in that the type of the operand of ADDR_EXPR
894 is not the target type of the type of the ADDR_EXPR itself.
895 Question is, can this lossage be avoided? */
902 }
903 /* This way is better for a COMPONENT_REF since it can
904 simplify the offset for a component. */
907 }
909 }
911 /* Perform default promotions for C data used in expressions.
912 Arrays and functions are converted to pointers;
913 enumeral types or short or char, to int.
914 In addition, manifest constants symbols are replaced by their values. */
916 tree
918 tree exp;
919 {
920 tree orig_exp;
927 /* Constants can be used directly unless they're not loadable. */
931 /* Replace a nonvolatile const static variable with its value unless
932 it is an array, in which case we must be sure that taking the
933 address of the array produces consistent results. */
935 {
938 }
940 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
941 an lvalue.
943 Do not use STRIP_NOPS here! It will remove conversions from pointer
944 to integer and cause infinite recursion. */
951 /* Preserve the original expression code. */
955 /* Normally convert enums to int,
956 but convert wide enums to something wider. */
958 {
966 }
970 /* If it's thinner than an int, promote it like a
971 c_promoting_integer_type_p, otherwise leave it alone. */
977 {
978 /* Preserve unsignedness if not really getting any wider. */
984 }
987 {
990 }
992 }
993 \f
994 /* Look up COMPONENT in a structure or union DECL.
996 If the component name is not found, returns NULL_TREE. Otherwise,
997 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
998 stepping down the chain to the component, which is in the last
999 TREE_VALUE of the list. Normally the list is of length one, but if
1000 the component is embedded within (nested) anonymous structures or
1001 unions, the list steps down the chain to the component. */
1003 static tree
1006 {
1008 tree field;
1010 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1011 to the field elements. Use a binary search on this array to quickly
1012 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1013 will always be set for structures which have many elements. */
1016 {
1024 {
1029 {
1030 /* Step through all anon unions in linear fashion. */
1032 {
1036 {
1041 }
1042 }
1044 /* Entire record is only anon unions. */
1048 /* Restart the binary search, with new lower bound. */
1050 }
1056 else
1058 }
1064 }
1065 else
1066 {
1068 {
1072 {
1077 }
1081 }
1085 }
1088 }
1090 /* Make an expression to refer to the COMPONENT field of
1091 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1093 tree
1096 {
1100 tree ref;
1102 /* If DATUM is a COMPOUND_EXPR, move our reference inside it.
1103 If pedantic ensure that the arguments are not lvalues; otherwise,
1104 if the component is an array, it would wrongly decay to a pointer in
1105 C89 mode.
1106 We cannot do this with a COND_EXPR, because in a conditional expression
1107 the default promotions are applied to both sides, and this would yield
1108 the wrong type of the result; for example, if the components have
1109 type "char". */
1111 {
1113 {
1117 }
1120 }
1122 /* See if there is a field or component with name COMPONENT. */
1125 {
1127 {
1130 }
1135 {
1140 }
1142 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1143 This might be better solved in future the way the C++ front
1144 end does it - by giving the anonymous entities each a
1145 separate name and type, and then have build_component_ref
1146 recursively call itself. We can't do that here. */
1148 {
1164 }
1167 }
1173 }
1174 \f
1175 /* Given an expression PTR for a pointer, return an expression
1176 for the value pointed to.
1177 ERRORSTRING is the name of the operator to appear in error messages. */
1179 tree
1181 tree ptr;
1183 {
1188 {
1190 && !flag_volatile
1194 else
1195 {
1200 {
1203 }
1207 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1208 so that we get the proper error message if the result is used
1209 to assign to. Also, &* is supposed to be a no-op.
1210 And ANSI C seems to specify that the type of the result
1211 should be the const type. */
1212 /* A de-reference of a pointer to const is not a const. It is valid
1213 to change it via some other pointer. */
1219 }
1220 }
1224 }
1226 /* This handles expressions of the form "a[i]", which denotes
1227 an array reference.
1229 This is logically equivalent in C to *(a+i), but we may do it differently.
1230 If A is a variable or a member, we generate a primitive ARRAY_REF.
1231 This avoids forcing the array out of registers, and can work on
1232 arrays that are not lvalues (for example, members of structures returned
1233 by functions). */
1235 tree
1238 {
1240 {
1243 }
1251 {
1254 /* Subscripting with type char is likely to lose
1255 on a machine where chars are signed.
1256 So warn on any machine, but optionally.
1257 Don't warn for unsigned char since that type is safe.
1258 Don't warn for signed char because anyone who uses that
1259 must have done so deliberately. */
1264 /* Apply default promotions *after* noticing character types. */
1267 /* Require integer *after* promotion, for sake of enums. */
1269 {
1272 }
1274 /* An array that is indexed by a non-constant
1275 cannot be stored in a register; we must be able to do
1276 address arithmetic on its address.
1277 Likewise an array of elements of variable size. */
1281 {
1284 }
1285 /* An array that is indexed by a constant value which is not within
1286 the array bounds cannot be stored in a register either; because we
1287 would get a crash in store_bit_field/extract_bit_field when trying
1288 to access a non-existent part of the register. */
1292 {
1295 }
1298 {
1306 }
1310 /* Array ref is const/volatile if the array elements are
1311 or if the array is. */
1320 /* This was added by rms on 16 Nov 91.
1321 It fixes vol struct foo *a; a->elts[1]
1322 in an inline function.
1323 Hope it doesn't break something else. */
1326 }
1328 {
1332 /* Do the same warning check as above, but only on the part that's
1333 syntactically the index and only if it is also semantically
1334 the index. */
1340 /* Put the integer in IND to simplify error checking. */
1342 {
1346 }
1353 {
1356 }
1358 {
1361 }
1365 }
1366 }
1367 \f
1368 /* Build an external reference to identifier ID. FUN indicates
1369 whether this will be used for a function call. */
1370 tree
1372 tree id;
1374 {
1375 tree ref;
1383 {
1387 {
1389 /* Ordinary implicit function declaration. */
1391 else
1392 {
1393 /* Implicit declaration of built-in function. Don't
1394 change the built-in declaration, but don't let this
1395 go by silently, either. */
1398 /* only issue this warning once */
1401 }
1402 }
1403 else
1404 {
1405 /* Reference to undeclared variable, including reference to
1406 builtin outside of function-call context. */
1410 else
1411 {
1414 {
1419 {
1423 }
1424 }
1427 }
1429 }
1430 }
1431 else
1432 {
1433 /* Properly declared variable or function reference. */
1437 {
1441 }
1442 else
1444 }
1454 {
1457 }
1460 }
1462 /* Build a function call to function FUNCTION with parameters PARAMS.
1463 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1464 TREE_VALUE of each node is a parameter-expression.
1465 FUNCTION's data type may be a function type or a pointer-to-function. */
1467 tree
1470 {
1472 tree coerced_params;
1475 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1478 /* Convert anything with function type to a pointer-to-function. */
1480 {
1484 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1485 (because calling an inline function does not mean the function
1486 needs to be separately compiled). */
1492 }
1493 else
1503 {
1506 }
1511 /* fntype now gets the type of function pointed to. */
1514 /* Convert the parameters to the types declared in the
1515 function prototype, or apply default promotions. */
1517 coerced_params
1520 /* Check that the arguments to the function are valid. */
1524 /* Recognize certain built-in functions so we can make tree-codes
1525 other than CALL_EXPR. We do this when it enables fold-const.c
1526 to do something useful. */
1531 {
1536 }
1546 }
1547 \f
1548 /* Convert the argument expressions in the list VALUES
1549 to the types in the list TYPELIST. The result is a list of converted
1550 argument expressions.
1552 If TYPELIST is exhausted, or when an element has NULL as its type,
1553 perform the default conversions.
1555 PARMLIST is the chain of parm decls for the function being called.
1556 It may be 0, if that info is not available.
1557 It is used only for generating error messages.
1559 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1561 This is also where warnings about wrong number of args are generated.
1563 Both VALUES and the returned value are chains of TREE_LIST nodes
1564 with the elements of the list in the TREE_VALUE slots of those nodes. */
1566 static tree
1569 {
1574 /* Scan the given expressions and types, producing individual
1575 converted arguments and pushing them on RESULT in reverse order. */
1578 valtail;
1580 {
1585 {
1589 else
1592 }
1594 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1595 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1596 to convert automatically to a pointer. */
1605 {
1606 /* Formal parm type is specified by a function prototype. */
1607 tree parmval;
1610 {
1613 }
1614 else
1615 {
1616 /* Optionally warn about conversions that
1617 differ from the default conversions. */
1619 {
1624 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1627 warn_for_assignment ("%s as integer rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1630 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1633 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1636 warn_for_assignment ("%s as complex rather than integer due to prototype", (char *) 0, name, parmnum + 1);
1639 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1640 /* ??? At some point, messages should be written about
1641 conversions between complex types, but that's too messy
1642 to do now. */
1645 {
1646 /* Warn if any argument is passed as `float',
1647 since without a prototype it would be `double'. */
1649 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
1650 }
1651 /* Detect integer changing in width or signedness.
1652 These warnings are only activated with
1653 -Wconversion, not with -Wtraditional. */
1656 {
1663 /* No warning if function asks for enum
1664 and the actual arg is that enum type. */
1665 ;
1667 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
1669 ;
1670 /* Don't complain if the formal parameter type
1671 is an enum, because we can't tell now whether
1672 the value was an enum--even the same enum. */
1674 ;
1677 /* Change in signedness doesn't matter
1678 if a constant value is unaffected. */
1679 ;
1680 /* Likewise for a constant in a NOP_EXPR. */
1684 ;
1689 /* Change in signedness doesn't matter
1690 if an enum value is unaffected. */
1691 ;
1692 #endif
1693 /* If the value is extended from a narrower
1694 unsigned type, it doesn't matter whether we
1695 pass it as signed or unsigned; the value
1696 certainly is the same either way. */
1699 ;
1702 else
1704 }
1705 }
1715 }
1717 }
1721 /* Convert `float' to `double'. */
1723 else
1724 /* Convert `short' and `char' to full-size `int'. */
1729 }
1732 {
1736 else
1738 }
1741 }
1742 \f
1743 /* This is the entry point used by the parser
1744 for binary operators in the input.
1745 In addition to constructing the expression,
1746 we check for operands that were written with other binary operators
1747 in a way that is likely to confuse the user. */
1749 tree
1753 {
1770 /* Check for cases such as x+y<<z which users are likely
1771 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
1772 is cleared to prevent these warnings. */
1774 {
1776 {
1780 }
1783 {
1787 }
1790 {
1796 /* Check cases like x|y==z */
1799 }
1802 {
1808 /* Check cases like x^y==z */
1811 }
1814 {
1818 /* Check cases like x&y==z */
1821 }
1822 }
1824 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
1835 /* Record the code that was specified in the source,
1836 for the sake of warnings about confusing nesting. */
1839 else
1840 {
1842 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
1843 so that convert_for_assignment wouldn't strip it.
1844 That way, we got warnings for things like p = (1 - 1).
1845 But it turns out we should not get those warnings. */
1849 }
1852 }
1854 /* Build a binary-operation expression without default conversions.
1855 CODE is the kind of expression to build.
1856 This function differs from `build' in several ways:
1857 the data type of the result is computed and recorded in it,
1858 warnings are generated if arg data types are invalid,
1859 special handling for addition and subtraction of pointers is known,
1860 and some optimization is done (operations on narrow ints
1861 are done in the narrower type when that gives the same result).
1862 Constant folding is also done before the result is returned.
1864 Note that the operands will never have enumeral types, or function
1865 or array types, because either they will have the default conversions
1866 performed or they have both just been converted to some other type in which
1867 the arithmetic is to be done. */
1869 tree
1874 {
1879 /* Expression code to give to the expression when it is built.
1880 Normally this is CODE, which is what the caller asked for,
1881 but in some special cases we change it. */
1884 /* Data type in which the computation is to be performed.
1885 In the simplest cases this is the common type of the arguments. */
1888 /* Nonzero means operands have already been type-converted
1889 in whatever way is necessary.
1890 Zero means they need to be converted to RESULT_TYPE. */
1893 /* Nonzero means create the expression with this type, rather than
1894 RESULT_TYPE. */
1897 /* Nonzero means after finally constructing the expression
1898 convert it to this type. */
1901 /* Nonzero if this is an operation like MIN or MAX which can
1902 safely be computed in short if both args are promoted shorts.
1903 Also implies COMMON.
1904 -1 indicates a bitwise operation; this makes a difference
1905 in the exact conditions for when it is safe to do the operation
1906 in a narrower mode. */
1909 /* Nonzero if this is a comparison operation;
1910 if both args are promoted shorts, compare the original shorts.
1911 Also implies COMMON. */
1914 /* Nonzero if this is a right-shift operation, which can be computed on the
1915 original short and then promoted if the operand is a promoted short. */
1918 /* Nonzero means set RESULT_TYPE to the common type of the args. */
1922 {
1925 }
1926 else
1927 {
1930 }
1935 /* The expression codes of the data types of the arguments tell us
1936 whether the arguments are integers, floating, pointers, etc. */
1940 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1944 /* If an error was already reported for one of the arguments,
1945 avoid reporting another error. */
1951 {
1953 /* Handle the pointer + int case. */
1958 else
1963 /* Subtraction of two similar pointers.
1964 We must subtract them as integers, then divide by object size. */
1968 /* Handle pointer minus int. Just like pointer plus int. */
1971 else
1984 /* Floating point division by zero is a legitimate way to obtain
1985 infinities and NaNs. */
1993 {
1996 else
1997 /* Although it would be tempting to shorten always here, that
1998 loses on some targets, since the modulo instruction is
1999 undefined if the quotient can't be represented in the
2000 computation mode. We shorten only if unsigned or if
2001 dividing by something we know != -1. */
2006 }
2025 {
2026 /* Although it would be tempting to shorten always here, that loses
2027 on some targets, since the modulo instruction is undefined if the
2028 quotient can't be represented in the computation mode. We shorten
2029 only if unsigned or if dividing by something we know != -1. */
2034 }
2046 {
2047 /* Result of these operations is always an int,
2048 but that does not mean the operands should be
2049 converted to ints! */
2054 }
2057 /* Shift operations: result has same type as first operand;
2058 always convert second operand to int.
2059 Also set SHORT_SHIFT if shifting rightward. */
2063 {
2065 {
2068 else
2069 {
2075 }
2076 }
2078 /* Use the type of the value to be shifted. */
2080 /* Convert the shift-count to an integer, regardless of size
2081 of value being shifted. */
2084 /* Avoid converting op1 to result_type later. */
2086 }
2091 {
2093 {
2099 }
2101 /* Use the type of the value to be shifted. */
2103 /* Convert the shift-count to an integer, regardless of size
2104 of value being shifted. */
2107 /* Avoid converting op1 to result_type later. */
2109 }
2115 {
2117 {
2122 }
2124 /* Use the type of the value to be shifted. */
2126 /* Convert the shift-count to an integer, regardless of size
2127 of value being shifted. */
2130 /* Avoid converting op1 to result_type later. */
2132 }
2139 /* Result of comparison is always int,
2140 but don't convert the args to int! */
2150 {
2153 /* Anything compares with void *. void * compares with anything.
2154 Otherwise, the targets must be compatible
2155 and both must be object or both incomplete. */
2159 {
2160 /* op0 != orig_op0 detects the case of something
2161 whose value is 0 but which isn't a valid null ptr const. */
2165 }
2167 {
2171 }
2172 else
2177 }
2185 {
2188 }
2190 {
2193 }
2202 {
2204 {
2209 }
2210 else
2211 {
2214 }
2215 }
2227 {
2229 {
2237 }
2238 else
2239 {
2242 }
2243 }
2246 {
2250 }
2253 {
2257 }
2259 {
2262 }
2264 {
2267 }
2279 {
2282 }
2288 }
2292 &&
2295 {
2301 /* For certain operations (which identify themselves by shorten != 0)
2302 if both args were extended from the same smaller type,
2303 do the arithmetic in that type and then extend.
2305 shorten !=0 and !=1 indicates a bitwise operation.
2306 For them, this optimization is safe only if
2307 both args are zero-extended or both are sign-extended.
2308 Otherwise, we might change the result.
2309 Eg, (short)-1 | (unsigned short)-1 is (int)-1
2310 but calculated in (unsigned short) it would be (unsigned short)-1. */
2313 {
2317 /* UNS is 1 if the operation to be done is an unsigned one. */
2319 tree type;
2323 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
2324 but it *requires* conversion to FINAL_TYPE. */
2335 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
2337 /* For bitwise operations, signedness of nominal type
2338 does not matter. Consider only how operands were extended. */
2342 /* Note that in all three cases below we refrain from optimizing
2343 an unsigned operation on sign-extended args.
2344 That would not be valid. */
2346 /* Both args variable: if both extended in same way
2347 from same width, do it in that width.
2348 Do it unsigned if args were zero-extended. */
2355 result_type
2356 = c_common_signed_or_unsigned_type
2362 && (type
2371 && (type
2376 }
2378 /* Shifts can be shortened if shifting right. */
2381 {
2391 /* We can shorten only if the shift count is less than the
2392 number of bits in the smaller type size. */
2394 /* We cannot drop an unsigned shift after sign-extension. */
2396 {
2397 /* Do an unsigned shift if the operand was zero-extended. */
2398 result_type
2401 /* Convert value-to-be-shifted to that type. */
2405 }
2406 }
2408 /* Comparison operations are shortened too but differently.
2409 They identify themselves by setting short_compare = 1. */
2412 {
2413 /* Don't write &op0, etc., because that would prevent op0
2414 from being kept in a register.
2415 Instead, make copies of the our local variables and
2416 pass the copies by reference, then copy them back afterward. */
2419 tree val
2431 {
2443 /* Give warnings for comparisons between signed and unsigned
2444 quantities that may fail.
2446 Do the checking based on the original operand trees, so that
2447 casts will be considered, but default promotions won't be.
2449 Do not warn if the comparison is being done in a signed type,
2450 since the signed type will only be chosen if it can represent
2451 all the values of the unsigned type. */
2454 /* Do not warn if both operands are the same signedness. */
2457 else
2458 {
2463 else
2466 /* Do not warn if the signed quantity is an
2467 unsuffixed integer literal (or some static
2468 constant expression involving such literals or a
2469 conditional expression involving such literals)
2470 and it is non-negative. */
2473 /* Do not warn if the comparison is an equality operation,
2474 the unsigned quantity is an integral constant, and it
2475 would fit in the result if the result were signed. */
2478 && int_fits_type_p
2481 /* Do not warn if the unsigned quantity is an enumeration
2482 constant and its maximum value would fit in the result
2483 if the result were signed. */
2486 && int_fits_type_p
2490 else
2492 }
2494 /* Warn if two unsigned values are being compared in a size
2495 larger than their original size, and one (and only one) is the
2496 result of a `~' operator. This comparison will always fail.
2498 Also warn if one operand is a constant, and the constant
2499 does not have all bits set that are set in the ~ operand
2500 when it is extended. */
2504 {
2508 else
2513 {
2514 tree primop;
2519 {
2523 }
2524 else
2525 {
2529 }
2534 {
2538 }
2539 }
2546 }
2547 }
2548 }
2549 }
2551 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
2552 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
2553 Then the expression will be built.
2554 It will be given type FINAL_TYPE if that is nonzero;
2555 otherwise, it will be given type RESULT_TYPE. */
2558 {
2561 }
2564 {
2569 }
2574 {
2576 tree folded;
2584 }
2585 }
2586 \f
2588 /* Return true if `t' is known to be non-negative. */
2590 int
2592 tree t;
2593 {
2595 {
2598 /* Find the last statement in the chain, ignoring the final
2599 * scope statement */
2604 }
2606 }
2608 /* Return a tree for the difference of pointers OP0 and OP1.
2609 The resulting tree has type int. */
2611 static tree
2614 {
2623 {
2628 }
2630 /* If the conversion to ptrdiff_type does anything like widening or
2631 converting a partial to an integral mode, we get a convert_expression
2632 that is in the way to do any simplifications.
2633 (fold-const.c doesn't know that the extra bits won't be needed.
2634 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2635 different mode in place.)
2636 So first try to find a common term here 'by hand'; we want to cover
2637 at least the cases that occur in legal static initializers. */
2642 {
2645 }
2646 else
2650 {
2653 }
2654 else
2658 {
2661 }
2664 /* First do the subtraction as integers;
2665 then drop through to build the divide operator.
2666 Do not do default conversions on the minus operator
2667 in case restype is a short type. */
2671 /* This generates an error if op1 is pointer to incomplete type. */
2675 /* This generates an error if op0 is pointer to incomplete type. */
2678 /* Divide by the size, in easiest possible way. */
2686 }
2687 \f
2688 /* Construct and perhaps optimize a tree representation
2689 for a unary operation. CODE, a tree_code, specifies the operation
2690 and XARG is the operand.
2691 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2692 the default promotions (such as from short to int).
2693 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2694 allows non-lvalues; this is only used to handle conversion of non-lvalue
2695 arrays to pointers in C99. */
2697 tree
2700 tree xarg;
2702 {
2703 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2707 tree val;
2716 {
2718 /* This is used for unary plus, because a CONVERT_EXPR
2719 is enough to prevent anybody from looking inside for
2720 associativity, but won't generate any code. */
2723 {
2726 }
2736 {
2739 }
2746 {
2749 }
2751 {
2757 }
2758 else
2759 {
2762 }
2768 {
2771 }
2777 /* Conjugating a real value is a no-op, but allow it anyway. */
2780 {
2783 }
2792 /* These will convert to a pointer. */
2794 {
2797 }
2809 else
2817 else
2824 /* Handle complex lvalues (when permitted)
2825 by reduction to simpler cases. */
2831 /* Increment or decrement the real part of the value,
2832 and don't change the imaginary part. */
2834 {
2845 }
2847 /* Report invalid types. */
2851 {
2854 else
2858 }
2860 {
2861 tree inc;
2867 /* Compute the increment. */
2870 {
2871 /* If pointer target is an undefined struct,
2872 we just cannot know how to do the arithmetic. */
2874 {
2877 else
2879 }
2883 {
2886 else
2888 }
2891 }
2892 else
2897 /* Handle incrementing a cast-expression. */
2901 {
2910 /* If the real type has the same machine representation
2911 as the type it is cast to, we can make better output
2912 by adding directly to the inside of the cast. */
2918 else
2919 {
2923 else
2924 {
2928 else
2937 }
2940 }
2945 }
2946 give_up:
2948 /* Complain about anything else that is not a true lvalue. */
2955 /* Report a read-only lvalue. */
2964 else
2971 }
2974 /* Note that this operation never does default_conversion. */
2976 /* Let &* cancel out to simplify resulting code. */
2978 {
2979 /* Don't let this be an lvalue. */
2983 }
2985 /* For &x[y], return x+y */
2987 {
2992 }
2994 /* Handle complex lvalues (when permitted)
2995 by reduction to simpler cases. */
3001 float f; *&(int)f = 3.4 stores in int format
3002 whereas (int)f = 3.4 stores in float format. */
3003 /* Address of a cast is just a cast of the address
3004 of the operand of the cast. */
3006 {
3019 }
3020 #endif
3022 /* Anything not already handled and not a true memory reference
3023 or a non-lvalue array is an error. */
3028 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3031 /* If the lvalue is const or volatile, merge that into the type
3032 to which the address will point. Note that you can't get a
3033 restricted pointer by taking the address of something, so we
3034 only have to deal with `const' and `volatile' here. */
3046 {
3047 tree addr;
3050 {
3056 {
3060 }
3065 }
3066 else
3069 /* Address of a static or external variable or
3070 file-scope function counts as a constant. */
3076 }
3080 }
3085 }
3087 #if 0
3088 /* If CONVERSIONS is a conversion expression or a nested sequence of such,
3089 convert ARG with the same conversions in the same order
3090 and return the result. */
3092 static tree
3094 tree conversions;
3095 tree arg;
3096 {
3098 {
3108 arg));
3112 }
3113 }
3116 /* Return nonzero if REF is an lvalue valid for this language.
3117 Lvalues can be assigned, unless their type has TYPE_READONLY.
3118 Lvalues can have their address taken, unless they have DECL_REGISTER. */
3120 int
3122 tree ref;
3123 {
3127 {
3152 }
3153 }
3155 /* Return nonzero if REF is an lvalue valid for this language;
3156 otherwise, print an error message and return zero. */
3158 int
3160 tree ref;
3162 {
3169 }
3171 /* Apply unary lvalue-demanding operator CODE to the expression ARG
3172 for certain kinds of expressions which are not really lvalues
3173 but which we can accept as lvalues. If FLAG is nonzero, then
3174 non-lvalues are OK since we may be converting a non-lvalue array to
3175 a pointer in C99.
3177 If ARG is not a kind of expression we can handle, return zero. */
3179 static tree
3182 tree arg;
3184 {
3185 /* Handle (a, b) used as an "lvalue". */
3187 {
3190 /* If this returns a function type, it isn't really being used as
3191 an lvalue, so don't issue a warning about it. */
3197 }
3199 /* Handle (a ? b : c) used as an "lvalue". */
3201 {
3211 }
3214 }
3216 /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR
3217 COMPOUND_EXPR, or CONVERT_EXPR (for casts). */
3219 static void
3222 {
3225 {
3235 }
3236 }
3237 \f
3238 /* Warn about storing in something that is `const'. */
3240 void
3242 tree arg;
3244 {
3246 {
3249 else
3252 }
3256 else
3258 }
3259 \f
3260 /* Mark EXP saying that we need to be able to take the
3261 address of it; it should not be allocated in a register.
3262 Returns true if successful. */
3264 bool
3266 tree exp;
3267 {
3272 {
3275 {
3279 }
3281 /* ... fall through ... */
3301 {
3303 {
3307 }
3310 }
3312 {
3314 {
3318 }
3320 /* If we are making this addressable due to its having
3321 volatile components, give a different error message. Also
3322 handle the case of an unnamed parameter by not trying
3323 to give the name. */
3326 {
3329 }
3333 }
3336 /* drops in */
3342 #endif
3346 }
3347 }
3348 \f
3349 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3351 tree
3354 {
3355 tree type1;
3356 tree type2;
3365 /* Don't promote the operands separately if they promote
3366 the same way. Return the unpromoted type and let the combined
3367 value get promoted if necessary. */
3373 {
3378 }
3379 #endif
3381 /* Promote both alternatives. */
3398 /* Quickly detect the usual case where op1 and op2 have the same type
3399 after promotion. */
3401 {
3404 else
3406 }
3411 {
3414 /* If -Wsign-compare, warn here if type1 and type2 have
3415 different signedness. We'll promote the signed to unsigned
3416 and later code won't know it used to be different.
3417 Do this check on the original types, so that explicit casts
3418 will be considered, but default promotions won't. */
3421 {
3426 {
3427 /* Do not warn if the result type is signed, since the
3428 signed type will only be chosen if it can represent
3429 all the values of the unsigned type. */
3432 /* Do not warn if the signed quantity is an unsuffixed
3433 integer literal (or some static constant expression
3434 involving such literals) and it is non-negative. */
3438 else
3440 }
3441 }
3442 }
3444 {
3448 }
3450 {
3460 {
3465 }
3467 {
3472 }
3473 else
3474 {
3477 }
3478 }
3480 {
3483 else
3484 {
3486 }
3488 }
3490 {
3493 else
3494 {
3496 }
3498 }
3501 {
3504 else
3505 {
3508 }
3509 }
3511 /* Merge const and volatile flags of the incoming types. */
3512 result_type
3526 }
3527 \f
3528 /* Given a list of expressions, return a compound expression
3529 that performs them all and returns the value of the last of them. */
3531 tree
3533 tree list;
3534 {
3536 }
3538 static tree
3540 tree list;
3542 {
3543 tree rest;
3546 {
3547 /* Convert arrays and functions to pointers when there
3548 really is a comma operator. */
3554 /* Consider (x, y+0), which is not an lvalue since y+0 is not. */
3556 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3559 #endif
3561 /* Don't let (0, 0) be null pointer constant. */
3565 }
3570 {
3571 /* The left-hand operand of a comma expression is like an expression
3572 statement: with -W or -Wunused, we should warn if it doesn't have
3573 any side-effects, unless it was explicitly cast to (void). */
3579 /* When pedantic, a compound expression can be neither an lvalue
3580 nor an integer constant expression. */
3583 }
3585 /* With -Wunused, we should also warn if the left-hand operand does have
3586 side-effects, but computes a value which is not used. For example, in
3587 `foo() + bar(), baz()' the result of the `+' operator is not used,
3588 so we should issue a warning. */
3593 }
3595 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3597 tree
3599 tree type;
3600 tree expr;
3601 {
3607 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3608 only in <protocol> qualifications. But when constructing cast expressions,
3609 the protocols do matter and must be kept around. */
3613 #if 0
3614 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3617 #endif
3620 {
3623 }
3626 {
3629 }
3632 {
3634 {
3638 }
3639 }
3641 {
3642 tree field;
3651 {
3653 tree t;
3658 {
3661 else
3663 }
3664 else
3670 }
3673 }
3674 else
3675 {
3678 /* If casting to void, avoid the error that would come
3679 from default_conversion in the case of a non-lvalue array. */
3683 /* Convert functions and arrays to pointers,
3684 but don't convert any other types. */
3688 /* Optionally warn about potentially worrisome casts. */
3693 {
3699 /* Check that the qualifiers on IN_TYPE are a superset of
3700 the qualifiers of IN_OTYPE. The outermost level of
3701 POINTER_TYPE nodes is uninteresting and we stop as soon
3702 as we hit a non-POINTER_TYPE node on either type. */
3703 do
3704 {
3708 /* GNU C allows cv-qualified function types. 'const'
3709 means the function is very pure, 'volatile' means it
3710 can't return. We need to warn when such qualifiers
3711 are added, not when they're taken away. */
3715 else
3717 }
3725 /* There are qualifiers present in IN_OTYPE that are not
3726 present in IN_TYPE. */
3728 }
3730 /* Warn about possible alignment problems. */
3736 /* Don't warn about opaque types, where the actual alignment
3737 restriction is unknown. */
3758 /* Don't warn about converting any constant. */
3768 {
3769 /* Casting the address of a decl to non void pointer. Warn
3770 if the cast breaks type based aliasing. */
3777 }
3782 /* Ignore any integer overflow caused by the cast. */
3784 {
3787 }
3788 }
3790 /* Pedantically, don't let (void *) (FOO *) 0 be a null pointer constant. */
3796 /* If pedantic, don't let a cast be an lvalue. */
3801 }
3803 /* Interpret a cast of expression EXPR to type TYPE. */
3804 tree
3807 {
3810 /* This avoids warnings about unprototyped casts on
3811 integers. E.g. "#define SIG_DFL (void(*)())0". */
3818 }
3820 \f
3821 /* Build an assignment expression of lvalue LHS from value RHS.
3822 MODIFYCODE is the code for a binary operator that we use
3823 to combine the old value of LHS with RHS to get the new value.
3824 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3826 tree
3830 {
3831 tree result;
3832 tree newrhs;
3836 /* Types that aren't fully specified cannot be used in assignments. */
3839 /* Avoid duplicate error messages from operands that had errors. */
3843 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3844 /* Do not use STRIP_NOPS here. We do not want an enumerator
3845 whose value is 0 to count as a null pointer constant. */
3851 /* Handle control structure constructs used as "lvalues". */
3854 {
3855 /* Handle (a, b) used as an "lvalue". */
3864 /* Handle (a ? b : c) used as an "lvalue". */
3868 {
3869 /* Produce (a ? (b = rhs) : (c = rhs))
3870 except that the RHS goes through a save-expr
3871 so the code to compute it is only emitted once. */
3872 tree cond
3880 /* Make sure the code to compute the rhs comes out
3881 before the split. */
3883 /* But cast it to void to avoid an "unused" error. */
3885 }
3888 }
3890 /* If a binary op has been requested, combine the old LHS value with the RHS
3891 producing the value we should actually store into the LHS. */
3894 {
3897 }
3899 /* Handle a cast used as an "lvalue".
3900 We have already performed any binary operator using the value as cast.
3901 Now convert the result to the cast type of the lhs,
3902 and then true type of the lhs and store it there;
3903 then convert result back to the cast type to be the value
3904 of the assignment. */
3907 {
3916 {
3918 tree result;
3926 }
3930 }
3932 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
3933 Reject anything strange now. */
3938 /* Warn about storing in something that is `const'. */
3946 /* If storing into a structure or union member,
3947 it has probably been given type `int'.
3948 Compute the type that would go with
3949 the actual amount of storage the member occupies. */
3958 /* If storing in a field that is in actuality a short or narrower than one,
3959 we must store in the field in its actual type. */
3962 {
3965 }
3967 /* Convert new value to destination type. */
3974 /* Scan operands */
3979 /* If we got the LHS in a different type for storing in,
3980 convert the result back to the nominal type of LHS
3981 so that the value we return always has the same type
3982 as the LHS argument. */
3988 }
3989 \f
3990 /* Convert value RHS to type TYPE as preparation for an assignment
3991 to an lvalue of type TYPE.
3992 The real work of conversion is done by `convert'.
3993 The purpose of this function is to generate error messages
3994 for assignments that are not allowed in C.
3995 ERRTYPE is a string to use in error messages:
3996 "assignment", "return", etc. If it is null, this is parameter passing
3997 for a function call (and different error messages are output).
3999 FUNNAME is the name of the function being called,
4000 as an IDENTIFIER_NODE, or null.
4001 PARMNUM is the number of the argument, for printing in error messages. */
4003 static tree
4009 {
4011 tree rhstype;
4014 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4015 /* Do not use STRIP_NOPS here. We do not want an enumerator
4016 whose value is 0 to count as a null pointer constant. */
4033 {
4035 /* Check for Objective-C protocols. This will automatically
4036 issue a warning if there are protocol violations. No need to
4037 use the return value. */
4041 }
4044 {
4047 }
4048 /* A type converts to a reference to it.
4049 This code doesn't fully support references, it's just for the
4050 special case of va_start and va_copy. */
4053 {
4055 {
4058 }
4063 /* We already know that these two types are compatible, but they
4064 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4065 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4066 likely to be va_list, a typedef to __builtin_va_list, which
4067 is different enough that it will cause problems later. */
4073 }
4074 /* Arithmetic types all interconvert, and enum is treated like int. */
4083 /* Conversion to a transparent union from its member types.
4084 This applies only to function arguments. */
4086 {
4087 tree memb_types;
4092 {
4103 {
4107 /* Any non-function converts to a [const][volatile] void *
4108 and vice versa; otherwise, targets must be the same.
4109 Meanwhile, the lhs target must have all the qualifiers of
4110 the rhs. */
4113 {
4114 /* If this type won't generate any warnings, use it. */
4124 /* Keep looking for a better type, but remember this one. */
4127 }
4128 }
4130 /* Can convert integer zero to any pointer type. */
4134 {
4137 }
4138 }
4141 {
4143 {
4144 /* We have only a marginally acceptable member type;
4145 it needs a warning. */
4149 /* Const and volatile mean something different for function
4150 types, so the usual warnings are not appropriate. */
4153 {
4154 /* Because const and volatile on functions are
4155 restrictions that say the function will not do
4156 certain things, it is okay to use a const or volatile
4157 function where an ordinary one is wanted, but not
4158 vice-versa. */
4162 }
4166 parmnum);
4167 }
4173 }
4174 }
4176 /* Conversions among pointers */
4179 {
4183 /* Any non-function converts to a [const][volatile] void *
4184 and vice versa; otherwise, targets must be the same.
4185 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4190 {
4193 ||
4195 /* Check TREE_CODE to catch cases like (void *) (char *) 0
4196 which are not ANSI null ptr constants. */
4201 /* Const and volatile mean something different for function types,
4202 so the usual warnings are not appropriate. */
4205 {
4209 /* If this is not a case of ignoring a mismatch in signedness,
4210 no warning. */
4213 ;
4214 /* If there is a mismatch, do warn. */
4218 }
4221 {
4222 /* Because const and volatile on functions are restrictions
4223 that say the function will not do certain things,
4224 it is okay to use a const or volatile function
4225 where an ordinary one is wanted, but not vice-versa. */
4229 }
4230 }
4231 else
4235 }
4237 {
4238 /* An explicit constant 0 can convert to a pointer,
4239 or one that results from arithmetic, even including
4240 a cast to integer type. */
4242 &&
4247 {
4251 }
4253 }
4255 {
4259 }
4264 {
4266 {
4272 else
4275 }
4276 else
4278 parmnum);
4279 }
4280 else
4284 }
4286 /* Convert VALUE for assignment into inlined parameter PARM. */
4288 tree
4291 {
4294 /* If FN was prototyped, the value has been converted already
4295 in convert_arguments. */
4308 }
4310 /* Print a warning using MSGID.
4311 It gets OPNAME as its one parameter.
4312 If OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
4313 FUNCTION and ARGNUM are handled specially if we are building an
4314 Objective-C selector. */
4316 static void
4320 tree function;
4322 {
4324 {
4329 {
4332 }
4334 {
4335 /* Function name is known; supply it. */
4342 }
4343 else
4344 {
4345 /* Function name unknown (call through ptr); just give arg number. */
4349 }
4351 }
4353 }
4354 \f
4355 /* If VALUE is a compound expr all of whose expressions are constant, then
4356 return its value. Otherwise, return error_mark_node.
4358 This is for handling COMPOUND_EXPRs as initializer elements
4359 which is allowed with a warning when -pedantic is specified. */
4361 static tree
4363 tree value;
4364 tree endtype;
4365 {
4367 {
4372 endtype);
4373 }
4377 else
4379 }
4380 \f
4381 /* Perform appropriate conversions on the initial value of a variable,
4382 store it in the declaration DECL,
4383 and print any error messages that are appropriate.
4384 If the init is invalid, store an ERROR_MARK. */
4386 void
4389 {
4392 /* If variable's type was invalidly declared, just ignore it. */
4398 /* Digest the specified initializer into an expression. */
4402 /* Store the expression if valid; else report error. */
4404 #if 0
4405 /* Note that this is the only place we can detect the error
4406 in a case such as struct foo bar = (struct foo) { x, y };
4407 where there is one initial value which is a constructor expression. */
4409 ;
4411 {
4414 }
4417 {
4420 }
4421 else
4422 {
4424 {
4429 }
4430 }
4431 #endif
4439 /* ANSI wants warnings about out-of-range constant initializers. */
4443 /* Check if we need to set array size from compound literal size. */
4447 {
4455 {
4459 {
4460 /* For int foo[] = (int [3]){1}; we need to set array size
4461 now since later on array initializer will be just the
4462 brace enclosed list of the compound literal. */
4466 }
4467 }
4468 }
4469 }
4470 \f
4471 /* Methods for storing and printing names for error messages. */
4473 /* Implement a spelling stack that allows components of a name to be pushed
4474 and popped. Each element on the stack is this structure. */
4476 struct spelling
4477 {
4479 union
4480 {
4484 };
4486 #define SPELLING_STRING 1
4487 #define SPELLING_MEMBER 2
4488 #define SPELLING_BOUNDS 3
4494 /* Macros to save and restore the spelling stack around push_... functions.
4495 Alternative to SAVE_SPELLING_STACK. */
4497 #define SPELLING_DEPTH() (spelling - spelling_base)
4498 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4500 /* Push an element on the spelling stack with type KIND and assign VALUE
4501 to MEMBER. */
4503 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4504 { \
4505 int depth = SPELLING_DEPTH (); \
4506 \
4507 if (depth >= spelling_size) \
4508 { \
4509 spelling_size += 10; \
4510 if (spelling_base == 0) \
4511 spelling_base \
4512 = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \
4513 else \
4514 spelling_base \
4515 = (struct spelling *) xrealloc (spelling_base, \
4516 spelling_size * sizeof (struct spelling)); \
4517 RESTORE_SPELLING_DEPTH (depth); \
4518 } \
4519 \
4520 spelling->kind = (KIND); \
4521 spelling->MEMBER = (VALUE); \
4522 spelling++; \
4523 }
4525 /* Push STRING on the stack. Printed literally. */
4527 static void
4530 {
4532 }
4534 /* Push a member name on the stack. Printed as '.' STRING. */
4536 static void
4538 tree decl;
4540 {
4544 }
4546 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4548 static void
4551 {
4553 }
4555 /* Compute the maximum size in bytes of the printed spelling. */
4557 static int
4559 {
4564 {
4567 else
4569 }
4572 }
4574 /* Print the spelling to BUFFER and return it. */
4579 {
4585 {
4588 }
4589 else
4590 {
4595 ;
4596 }
4599 }
4601 /* Issue an error message for a bad initializer component.
4602 MSGID identifies the message.
4603 The component name is taken from the spelling stack. */
4605 void
4608 {
4615 }
4617 /* Issue a pedantic warning for a bad initializer component.
4618 MSGID identifies the message.
4619 The component name is taken from the spelling stack. */
4621 void
4624 {
4631 }
4633 /* Issue a warning for a bad initializer component.
4634 MSGID identifies the message.
4635 The component name is taken from the spelling stack. */
4637 static void
4640 {
4647 }
4648 \f
4649 /* Digest the parser output INIT as an initializer for type TYPE.
4650 Return a C expression of type TYPE to represent the initial value.
4652 REQUIRE_CONSTANT requests an error if non-constant initializers or
4653 elements are seen. */
4655 static tree
4659 {
4668 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4669 /* Do not use STRIP_NOPS here. We do not want an enumerator
4670 whose value is 0 to count as a null pointer constant. */
4676 /* Initialization of an array of chars from a string constant
4677 optionally enclosed in braces. */
4680 {
4688 {
4696 {
4699 }
4703 {
4706 }
4712 /* Subtract 1 (or sizeof (wchar_t))
4713 because it's ok to ignore the terminating null char
4714 that is counted in the length of the constant. */
4725 }
4726 }
4728 /* Any type can be initialized
4729 from an expression of the same type, optionally with braces. */
4743 {
4749 {
4750 /* As an extension, allow initializing objects with static storage
4751 duration with compound literals (which are then treated just as
4752 the brace enclosed list they contain). */
4755 }
4759 {
4762 }
4767 /* Compound expressions can only occur here if -pedantic or
4768 -pedantic-errors is specified. In the later case, we always want
4769 an error. In the former case, we simply want a warning. */
4772 {
4773 inside_init
4778 else
4782 }
4785 /* This test catches things like `7 / 0' which
4786 result in an expression for which TREE_CONSTANT
4787 is true, but which is not actually something
4788 that is a legal constant. We really should not
4789 be using this function, because it is a part of
4790 the back-end. Instead, the expression should
4791 already have been turned into ERROR_MARK_NODE. */
4794 {
4797 }
4800 }
4802 /* Handle scalar types, including conversions. */
4806 {
4807 /* Note that convert_for_assignment calls default_conversion
4808 for arrays and functions. We must not call it in the
4809 case where inside_init is a null pointer constant. */
4810 inside_init
4815 {
4818 }
4821 {
4824 }
4827 }
4829 /* Come here only for records and arrays. */
4832 {
4835 }
4839 }
4840 \f
4841 /* Handle initializers that use braces. */
4843 /* Type of object we are accumulating a constructor for.
4844 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4847 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4848 left to fill. */
4851 /* For an ARRAY_TYPE, this is the specified index
4852 at which to store the next element we get. */
4855 /* For an ARRAY_TYPE, this is the maximum index. */
4858 /* For a RECORD_TYPE, this is the first field not yet written out. */
4861 /* For an ARRAY_TYPE, this is the index of the first element
4862 not yet written out. */
4865 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4866 This is so we can generate gaps between fields, when appropriate. */
4869 /* If we are saving up the elements rather than allocating them,
4870 this is the list of elements so far (in reverse order,
4871 most recent first). */
4874 /* 1 if constructor should be incrementally stored into a constructor chain,
4875 0 if all the elements should be kept in AVL tree. */
4878 /* 1 if so far this constructor's elements are all compile-time constants. */
4881 /* 1 if so far this constructor's elements are all valid address constants. */
4884 /* 1 if this constructor is erroneous so far. */
4887 /* 1 if have called defer_addressed_constants. */
4890 /* Structure for managing pending initializer elements, organized as an
4891 AVL tree. */
4893 struct init_node
4894 {
4898 tree purpose;
4899 tree value;
4900 };
4902 /* Tree of pending elements at this constructor level.
4903 These are elements encountered out of order
4904 which belong at places we haven't reached yet in actually
4905 writing the output.
4906 Will never hold tree nodes across GC runs. */
4909 /* The SPELLING_DEPTH of this constructor. */
4912 /* 0 if implicitly pushing constructor levels is allowed. */
4918 /* DECL node for which an initializer is being read.
4919 0 means we are reading a constructor expression
4920 such as (struct foo) {...}. */
4923 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4926 /* Nonzero if this is an initializer for a top-level decl. */
4929 /* Nonzero if there were any member designators in this initializer. */
4932 /* Nesting depth of designator list. */
4935 /* Nonzero if there were diagnosed errors in this designator list. */
4938 \f
4939 /* This stack has a level for each implicit or explicit level of
4940 structuring in the initializer, including the outermost one. It
4941 saves the values of most of the variables above. */
4945 struct constructor_stack
4946 {
4948 tree type;
4949 tree fields;
4950 tree index;
4951 tree max_index;
4952 tree unfilled_index;
4953 tree unfilled_fields;
4954 tree bit_index;
4955 tree elements;
4959 /* If nonzero, this value should replace the entire
4960 constructor at this level. */
4961 tree replacement_value;
4970 };
4974 /* This stack represents designators from some range designator up to
4975 the last designator in the list. */
4977 struct constructor_range_stack
4978 {
4981 tree range_start;
4982 tree index;
4983 tree range_end;
4984 tree fields;
4985 };
4989 /* This stack records separate initializers that are nested.
4990 Nested initializers can't happen in ANSI C, but GNU C allows them
4991 in cases like { ... (struct foo) { ... } ... }. */
4993 struct initializer_stack
4994 {
4996 tree decl;
5000 tree elements;
5008 };
5011 \f
5012 /* Prepare to parse and output the initializer for variable DECL. */
5014 void
5016 tree decl;
5017 tree asmspec_tree;
5019 {
5050 {
5052 require_constant_elements
5054 /* For a scalar, you can always use any value to initialize,
5055 even within braces. */
5061 }
5062 else
5063 {
5067 }
5080 }
5082 void
5084 {
5087 /* Output subconstants (string constants, usually)
5088 that were referenced within this initializer and saved up.
5089 Must do this if and only if we called defer_addressed_constants. */
5093 /* Free the whole constructor stack of this initializer. */
5095 {
5099 }
5104 /* Pop back to the data of the outer initializer (if any). */
5119 }
5120 \f
5121 /* Call here when we see the initializer is surrounded by braces.
5122 This is instead of a call to push_init_level;
5123 it is matched by a call to pop_init_level.
5125 TYPE is the type to initialize, for a constructor expression.
5126 For an initializer for a decl, TYPE is zero. */
5128 void
5130 tree type;
5131 {
5173 {
5175 /* Skip any nameless bit fields at the beginning. */
5182 }
5184 {
5186 {
5187 constructor_max_index
5190 /* Detect non-empty initializations of zero-length arrays. */
5195 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5196 to initialize VLAs will cause an proper error; avoid tree
5197 checking errors as well by setting a safe value. */
5202 constructor_index
5205 }
5206 else
5210 }
5212 {
5213 /* Vectors are like simple fixed-size arrays. */
5214 constructor_max_index =
5218 }
5219 else
5220 {
5221 /* Handle the case of int x = {5}; */
5224 }
5225 }
5226 \f
5227 /* Push down into a subobject, for initialization.
5228 If this is for an explicit set of braces, IMPLICIT is 0.
5229 If it is because the next element belongs at a lower level,
5230 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5232 void
5235 {
5239 /* If we've exhausted any levels that didn't have braces,
5240 pop them now. */
5242 {
5250 else
5252 }
5254 /* Unless this is an explicit brace, we need to preserve previous
5255 content if any. */
5257 {
5264 }
5297 {
5302 }
5304 /* Don't die if an entire brace-pair level is superfluous
5305 in the containing level. */
5307 ;
5310 {
5311 /* Don't die if there are extra init elts at the end. */
5314 else
5315 {
5318 constructor_depth++;
5319 }
5320 }
5322 {
5325 constructor_depth++;
5326 }
5329 {
5334 }
5337 {
5345 }
5348 {
5351 }
5355 {
5357 /* Skip any nameless bit fields at the beginning. */
5364 }
5366 {
5367 /* Vectors are like simple fixed-size arrays. */
5368 constructor_max_index =
5372 }
5374 {
5376 {
5377 constructor_max_index
5380 /* Detect non-empty initializations of zero-length arrays. */
5385 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5386 to initialize VLAs will cause an proper error; avoid tree
5387 checking errors as well by setting a safe value. */
5392 constructor_index
5395 }
5396 else
5401 {
5402 /* We need to split the char/wchar array into individual
5403 characters, so that we don't have to special case it
5404 everywhere. */
5406 }
5407 }
5408 else
5409 {
5413 }
5414 }
5416 /* At the end of an implicit or explicit brace level,
5417 finish up that level of constructor.
5418 If we were outputting the elements as they are read, return 0
5419 from inner levels (process_init_element ignores that),
5420 but return error_mark_node from the outermost level
5421 (that's what we want to put in DECL_INITIAL).
5422 Otherwise, return a CONSTRUCTOR expression. */
5424 tree
5427 {
5432 {
5433 /* When we come to an explicit close brace,
5434 pop any inner levels that didn't have explicit braces. */
5440 }
5444 /* Error for initializing a flexible array member, or a zero-length
5445 array member in an inappropriate context. */
5450 {
5451 /* Silently discard empty initializations. The parser will
5452 already have pedwarned for empty brackets. */
5456 {
5462 /* We have already issued an error message for the existence
5463 of a flexible array member not at the end of the structure.
5464 Discard the initializer so that we do not abort later. */
5467 }
5468 else
5469 /* Zero-length arrays are no longer special, so we should no longer
5470 get here. */
5472 }
5474 /* Warn when some struct elements are implicitly initialized to zero. */
5476 && constructor_type
5479 {
5480 /* Do not warn for flexible array members or zero-length arrays. */
5486 /* Do not warn if this level of the initializer uses member
5487 designators; it is likely to be deliberate. */
5489 {
5493 }
5494 }
5496 /* Now output all pending elements. */
5500 /* Pad out the end of the structure. */
5502 /* If this closes a superfluous brace pair,
5503 just pass out the element between them. */
5506 ;
5511 {
5512 /* A nonincremental scalar initializer--just return
5513 the element, after verifying there is just one. */
5515 {
5519 }
5521 {
5524 }
5525 else
5527 }
5528 else
5529 {
5532 else
5533 {
5540 }
5541 }
5566 {
5570 }
5572 }
5574 /* Common handling for both array range and field name designators.
5575 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5577 static int
5580 {
5581 tree subtype;
5584 /* Don't die if an entire brace-pair level is superfluous
5585 in the containing level. */
5589 /* If there were errors in this designator list already, bail out silently. */
5594 {
5598 /* Designator list starts at the level of closest explicit
5599 braces. */
5604 }
5607 {
5610 }
5614 {
5618 }
5620 {
5622 }
5623 else
5628 {
5631 }
5633 {
5636 }
5641 }
5643 /* If there are range designators in designator list, push a new designator
5644 to constructor_range_stack. RANGE_END is end of such stack range or
5645 NULL_TREE if there is no range designator at this level. */
5647 static void
5649 tree range_end;
5650 {
5665 }
5667 /* Within an array initializer, specify the next index to be initialized.
5668 FIRST is that index. If LAST is nonzero, then initialize a range
5669 of indices, running from FIRST through LAST. */
5671 void
5674 {
5704 else
5705 {
5709 {
5713 {
5716 }
5717 else
5718 {
5722 {
5725 }
5726 }
5727 }
5729 designator_depth++;
5733 }
5734 }
5736 /* Within a struct initializer, specify the next field to be initialized. */
5738 void
5740 tree fieldname;
5741 {
5742 tree tail;
5751 {
5754 }
5758 {
5761 }
5766 else
5767 {
5769 designator_depth++;
5773 }
5774 }
5775 \f
5776 /* Add a new initializer to the tree of pending initializers. PURPOSE
5777 identifies the initializer, either array index or field in a structure.
5778 VALUE is the value of that index or field. */
5780 static void
5783 {
5790 {
5792 {
5798 else
5799 {
5804 }
5805 }
5806 }
5807 else
5808 {
5809 tree bitpos;
5813 {
5819 else
5820 {
5825 }
5826 }
5827 }
5840 {
5844 {
5848 {
5850 {
5851 /* L rotation. */
5864 {
5867 else
5869 }
5870 else
5872 }
5873 else
5874 {
5875 /* LR rotation. */
5897 {
5900 else
5902 }
5903 else
5905 }
5907 }
5908 else
5909 {
5910 /* p->balance == +1; growth of left side balances the node. */
5913 }
5914 }
5916 {
5918 /* Growth propagation from right side. */
5921 {
5923 {
5924 /* R rotation. */
5937 {
5940 else
5942 }
5943 else
5945 }
5947 {
5948 /* RL rotation */
5970 {
5973 else
5975 }
5976 else
5978 }
5980 }
5981 else
5982 {
5983 /* p->balance == -1; growth of right side balances the node. */
5986 }
5987 }
5991 }
5992 }
5994 /* Build AVL tree from a sorted chain. */
5996 static void
5998 {
5999 tree chain;
6009 {
6011 /* Skip any nameless bit fields at the beginning. */
6017 }
6019 {
6021 constructor_unfilled_index
6024 else
6026 }
6028 }
6030 /* Build AVL tree from a string constant. */
6032 static void
6034 tree str;
6035 {
6050 else
6061 {
6063 {
6066 }
6067 else
6068 {
6072 {
6075 else
6080 }
6081 }
6084 {
6087 {
6089 {
6092 }
6093 }
6095 {
6098 }
6103 }
6108 }
6111 }
6113 /* Return value of FIELD in pending initializer or zero if the field was
6114 not initialized yet. */
6116 static tree
6118 tree field;
6119 {
6123 {
6130 {
6135 else
6137 }
6138 }
6140 {
6144 && (!constructor_unfilled_fields
6151 {
6156 else
6158 }
6159 }
6161 {
6165 }
6167 }
6169 /* "Output" the next constructor element.
6170 At top level, really output it to assembler code now.
6171 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6172 TYPE is the data type that the containing data type wants here.
6173 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6175 PENDING if non-nil means output pending elements that belong
6176 right after this element. (PENDING is normally 1;
6177 it is 0 while outputting pending elements, to avoid recursion.) */
6179 static void
6183 {
6195 {
6196 /* As an extension, allow initializing objects with static storage
6197 duration with compound literals (which are then treated just as
6198 the brace enclosed list they contain). */
6201 }
6215 {
6218 }
6223 /* If this field is empty (and not at the end of structure),
6224 don't do anything other than checking the initializer. */
6235 {
6238 }
6240 /* If this element doesn't come next in sequence,
6241 put it on constructor_pending_elts. */
6243 && (!constructor_incremental
6245 {
6252 }
6254 && (!constructor_incremental
6256 {
6257 /* We do this for records but not for unions. In a union,
6258 no matter which field is specified, it can be initialized
6259 right away since it starts at the beginning of the union. */
6261 {
6264 else
6265 {
6273 }
6274 }
6278 }
6281 {
6285 /* We can have just one union field set. */
6287 }
6289 /* Otherwise, output this element either to
6290 constructor_elements or to the assembler file. */
6294 constructor_elements
6297 /* Advance the variable that indicates sequential elements output. */
6299 constructor_unfilled_index
6301 bitsize_one_node);
6303 {
6304 constructor_unfilled_fields
6307 /* Skip any nameless bit fields. */
6311 constructor_unfilled_fields =
6313 }
6317 /* Now output any pending elements which have become next. */
6320 }
6322 /* Output any pending elements which have become next.
6323 As we output elements, constructor_unfilled_{fields,index}
6324 advances, which may cause other elements to become next;
6325 if so, they too are output.
6327 If ALL is 0, we return when there are
6328 no more pending elements to output now.
6330 If ALL is 1, we output space as necessary so that
6331 we can output all the pending elements. */
6333 static void
6336 {
6338 tree next;
6340 retry:
6342 /* Look thru the whole pending tree.
6343 If we find an element that should be output now,
6344 output it. Otherwise, set NEXT to the element
6345 that comes first among those still pending. */
6349 {
6351 {
6353 constructor_unfilled_index))
6359 {
6360 /* Advance to the next smaller node. */
6363 else
6364 {
6365 /* We have reached the smallest node bigger than the
6366 current unfilled index. Fill the space first. */
6369 }
6370 }
6371 else
6372 {
6373 /* Advance to the next bigger node. */
6376 else
6377 {
6378 /* We have reached the biggest node in a subtree. Find
6379 the parent of it, which is the next bigger node. */
6385 {
6388 }
6389 }
6390 }
6391 }
6394 {
6397 /* If the current record is complete we are done. */
6403 /* We can't compare fields here because there might be empty
6404 fields in between. */
6406 {
6410 }
6412 {
6413 /* Advance to the next smaller node. */
6416 else
6417 {
6418 /* We have reached the smallest node bigger than the
6419 current unfilled field. Fill the space first. */
6422 }
6423 }
6424 else
6425 {
6426 /* Advance to the next bigger node. */
6429 else
6430 {
6431 /* We have reached the biggest node in a subtree. Find
6432 the parent of it, which is the next bigger node. */
6439 {
6442 }
6443 }
6444 }
6445 }
6446 }
6448 /* Ordinarily return, but not if we want to output all
6449 and there are elements left. */
6453 /* If it's not incremental, just skip over the gap, so that after
6454 jumping to retry we will output the next successive element. */
6461 /* ELT now points to the node in the pending tree with the next
6462 initializer to output. */
6464 }
6465 \f
6466 /* Add one non-braced element to the current constructor level.
6467 This adjusts the current position within the constructor's type.
6468 This may also start or terminate implicit levels
6469 to handle a partly-braced initializer.
6471 Once this has found the correct level for the new element,
6472 it calls output_init_element. */
6474 void
6476 tree value;
6477 {
6484 /* Handle superfluous braces around string cst as in
6485 char x[] = {"foo"}; */
6487 && constructor_type
6491 {
6496 }
6499 {
6502 }
6504 /* Ignore elements of a brace group if it is entirely superfluous
6505 and has already been diagnosed. */
6509 /* If we've exhausted any levels that didn't have braces,
6510 pop them now. */
6512 {
6520 constructor_index)))
6522 else
6524 }
6526 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6528 {
6529 /* If value is a compound literal and we'll be just using its
6530 content, don't put it into a SAVE_EXPR. */
6532 || !require_constant_value
6535 }
6538 {
6540 {
6541 tree fieldtype;
6545 {
6548 }
6555 /* Error for non-static initialization of a flexible array member. */
6557 && !require_constant_value
6560 {
6563 }
6565 /* Accept a string constant to initialize a subarray. */
6571 /* Otherwise, if we have come to a subaggregate,
6572 and we don't have an element of its type, push into it. */
6578 {
6581 }
6584 {
6588 }
6589 else
6590 /* Do the bookkeeping for an element that was
6591 directly output as a constructor. */
6592 {
6593 /* For a record, keep track of end position of last field. */
6595 constructor_bit_index
6601 /* Skip any nameless bit fields. */
6605 constructor_unfilled_fields =
6607 }
6610 /* Skip any nameless bit fields at the beginning. */
6615 }
6617 {
6618 tree fieldtype;
6622 {
6625 }
6632 /* Warn that traditional C rejects initialization of unions.
6633 We skip the warning if the value is zero. This is done
6634 under the assumption that the zero initializer in user
6635 code appears conditioned on e.g. __STDC__ to avoid
6636 "missing initializer" warnings and relies on default
6637 initialization to zero in the traditional C case.
6638 We also skip the warning if the initializer is designated,
6639 again on the assumption that this must be conditional on
6640 __STDC__ anyway (and we've already complained about the
6641 member-designator already). */
6646 /* Accept a string constant to initialize a subarray. */
6652 /* Otherwise, if we have come to a subaggregate,
6653 and we don't have an element of its type, push into it. */
6659 {
6662 }
6665 {
6669 }
6670 else
6671 /* Do the bookkeeping for an element that was
6672 directly output as a constructor. */
6673 {
6676 }
6679 }
6681 {
6685 /* Accept a string constant to initialize a subarray. */
6691 /* Otherwise, if we have come to a subaggregate,
6692 and we don't have an element of its type, push into it. */
6698 {
6701 }
6706 {
6709 }
6711 /* Now output the actual element. */
6713 {
6717 }
6719 constructor_index
6723 /* If we are doing the bookkeeping for an element that was
6724 directly output as a constructor, we must update
6725 constructor_unfilled_index. */
6727 }
6729 {
6732 /* Do a basic check of initializer size. Note that vectors
6733 always have a fixed size derived from their type. */
6735 {
6738 }
6740 /* Now output the actual element. */
6744 constructor_index
6748 /* If we are doing the bookkeeping for an element that was
6749 directly output as a constructor, we must update
6750 constructor_unfilled_index. */
6752 }
6754 /* Handle the sole element allowed in a braced initializer
6755 for a scalar variable. */
6757 {
6760 }
6761 else
6762 {
6766 }
6768 /* Handle range initializers either at this level or anywhere higher
6769 in the designator stack. */
6771 {
6778 {
6782 }
6786 {
6790 }
6797 {
6801 {
6804 }
6812 }
6817 }
6820 }
6823 }
6824 \f
6825 /* Build a simple asm-statement, from one string literal. */
6826 tree
6828 tree expr;
6829 {
6836 {
6837 tree stmt;
6841 NULL_TREE));
6844 }
6848 }
6850 /* Build an asm-statement, whose components are a CV_QUALIFIER, a
6851 STRING, some OUTPUTS, some INPUTS, and some CLOBBERS. */
6853 tree
6855 tree cv_qualifier;
6856 tree string;
6857 tree outputs;
6858 tree inputs;
6859 tree clobbers;
6860 {
6861 tree tail;
6864 {
6867 }
6871 {
6875 }
6877 /* We can remove output conversions that change the type,
6878 but not the mode. */
6880 {
6886 /* Allow conversions as LHS here. build_modify_expr as called below
6887 will do the right thing with them. */
6898 }
6900 /* Remove output conversions that change the type but not the mode. */
6902 {
6906 }
6908 /* Perform default conversions on array and function inputs.
6909 Don't do this for other types as it would screw up operands
6910 expected to be in memory. */
6916 }
6918 /* Expand an ASM statement with operands, handling output operands
6919 that are not variables or INDIRECT_REFS by transforming such
6920 cases into cases that expand_asm_operands can handle.
6922 Arguments are same as for expand_asm_operands. */
6924 void
6930 {
6933 /* o[I] is the place that output number I should be written. */
6935 tree tail;
6937 /* Record the contents of OUTPUTS before it is modified. */
6941 /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of
6942 OUTPUTS some trees for where the values were actually stored. */
6945 /* Copy all the intermediate outputs into the specified outputs. */
6947 {
6949 {
6954 /* Restore the original value so that it's correct the next
6955 time we expand this function. */
6957 }
6958 /* Detect modification of read-only values.
6959 (Otherwise done by build_modify_expr.) */
6960 else
6961 {
6969 }
6970 }
6972 /* Those MODIFY_EXPRs could do autoincrements. */
6974 }
6975 \f
6976 /* Expand a C `return' statement.
6977 RETVAL is the expression for what to return,
6978 or a null pointer for `return;' with no value. */
6980 tree
6982 tree retval;
6983 {
6990 {
6995 }
6997 {
7001 }
7002 else
7003 {
7007 tree inner;
7015 /* Strip any conversions, additions, and subtractions, and see if
7016 we are returning the address of a local variable. Warn if so. */
7018 {
7020 {
7027 /* If the second operand of the MINUS_EXPR has a pointer
7028 type (or is converted from it), this may be valid, so
7029 don't give a warning. */
7030 {
7044 }
7061 }
7064 }
7067 }
7070 }
7071 \f
7073 /* The SWITCH_STMT being built. */
7074 tree switch_stmt;
7075 /* A splay-tree mapping the low element of a case range to the high
7076 element, or NULL_TREE if there is no high element. Used to
7077 determine whether or not a new case label duplicates an old case
7078 label. We need a tree, rather than simply a hash table, because
7079 of the GNU case range extension. */
7080 splay_tree cases;
7081 /* The next node on the stack. */
7083 };
7085 /* A stack of the currently active switch statements. The innermost
7086 switch statement is on the top of the stack. There is no need to
7087 mark the stack for garbage collection because it is only active
7088 during the processing of the body of a function, and we never
7089 collect at that point. */
7093 /* Start a C switch statement, testing expression EXP. Return the new
7094 SWITCH_STMT. */
7096 tree
7098 tree exp;
7099 {
7105 {
7111 {
7114 }
7115 else
7116 {
7126 }
7127 }
7129 /* Add this new SWITCH_STMT to the stack. */
7137 }
7139 /* Process a case label. */
7141 tree
7143 tree low_value;
7144 tree high_value;
7145 {
7149 {
7155 }
7158 else
7162 }
7164 /* Finish the switch statement. */
7166 void
7168 {
7173 /* Pop the stack. */
7177 }