Index: objc/ChangeLog =================================================================== --- objc/ChangeLog (revision 170370) +++ objc/ChangeLog (working copy) @@ -1,10 +1,19 @@ 2011-02-20 Nicola Pero - * objc-gnu-runtime-abi-01.c (TARGET_64BIT): Removed. Removed - usage of padding fields. Do not include tm.h. - * objc-act.c (objc_write_global_declaration): Set input_location - to BUILTINS_LOCATION while generating runtime metadata. + PR objc/47832 + * objc-act.c (flexible_array_type_p): New. + (add_instance_variable): Produce an error if an instance variable + is of flexible array type. + (encode_array): Do not emit an error if encoding a flexible array + type while generating instance variables. +2011-02-20 Nicola Pero + + * objc-gnu-runtime-abi-01.c (TARGET_64BIT): Removed. Removed + usage of padding fields. Do not include tm.h. + * objc-act.c (objc_write_global_declaration): Set input_location + to BUILTINS_LOCATION while generating runtime metadata. + 2011-01-20 Nicola Pero PR objc/47784 Index: objc/objc-act.c =================================================================== --- objc/objc-act.c (revision 170370) +++ objc/objc-act.c (working copy) @@ -5925,6 +5925,49 @@ add_category (tree klass, tree category) } } +/* TODO: The check for flexible array members in instance variables is + implemented only for ObjC, and it is implemented by using this + flexible_array_type_p() function, which is basically lifted from + c-decl.c. Is this the best way of doing the check ? */ + +/* flexible_array_type_p() seems to crash the compiler when used in + ObjC++, so we disable the check in ObjC++. */ +#ifndef OBJCPLUS +/* Determine whether TYPE is a structure with a flexible array member, + or a union containing such a structure (possibly recursively). These + are invalid as instance variable. */ + +static bool +flexible_array_type_p (tree type) +{ + tree x; + switch (TREE_CODE (type)) + { + case RECORD_TYPE: + x = TYPE_FIELDS (type); + if (x == NULL_TREE) + return false; + while (DECL_CHAIN (x) != NULL_TREE) + x = DECL_CHAIN (x); + if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE + && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE + && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE + && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE) + return true; + return false; + case UNION_TYPE: + for (x = TYPE_FIELDS (type); x != NULL_TREE; x = DECL_CHAIN (x)) + { + if (flexible_array_type_p (TREE_TYPE (x))) + return true; + } + return false; + default: + return false; + } +} +#endif + /* Called after parsing each instance variable declaration. Necessary to preserve typedefs and implement public/private... @@ -5958,6 +6001,27 @@ add_instance_variable (tree klass, objc_ivar_visib return klass; } + /* Also, reject a struct with a flexible array member. Ie, + + struct A { int x; int[] y; }; + + @interface X + { + struct A instance_variable; + } + @end + + is not valid as 'struct A' doesn't have a known size. */ +#ifndef OBJCPLUS + /* TODO: Implemented this check for ObjC++ too. */ + if (flexible_array_type_p (field_type)) + { + error ("instance variable %qs has unknown size", ivar_name); + /* Return class as is without adding this ivar. */ + return klass; + } +#endif + #ifdef OBJCPLUS /* Check if the ivar being added has a non-POD C++ type. If so, we will need to either (1) warn the user about it or (2) generate suitable @@ -9926,27 +9990,23 @@ encode_array (tree type, int curtype, int format) if (an_int_cst == NULL) { /* We are trying to encode an incomplete array. An incomplete - array is forbidden as part of an instance variable. */ - if (generating_instance_variables) - { - /* TODO: Detect this error earlier. */ - error ("instance variable has unknown size"); - return; - } + array is forbidden as part of an instance variable; but it + may occur if the instance variable is a pointer to such an + array. */ - /* So the only case in which an incomplete array could occur is - if we are encoding the arguments or return value of a method. - In that case, an incomplete array argument or return value - (eg, -(void)display: (char[])string) is treated like a - pointer because that is how the compiler does the function - call. A special, more complicated case, is when the - incomplete array is the last member of a struct (eg, if we - are encoding "struct { unsigned long int a;double b[];}"), - which is again part of a method argument/return value. In - that case, we really need to communicate to the runtime that - there is an incomplete array (not a pointer!) there. So, we - detect that special case and encode it as a zero-length - array. + /* So the only case in which an incomplete array could occur + (without being pointed to) is if we are encoding the + arguments or return value of a method. In that case, an + incomplete array argument or return value (eg, + -(void)display: (char[])string) is treated like a pointer + because that is how the compiler does the function call. A + special, more complicated case, is when the incomplete array + is the last member of a struct (eg, if we are encoding + "struct { unsigned long int a;double b[];}"), which is again + part of a method argument/return value. In that case, we + really need to communicate to the runtime that there is an + incomplete array (not a pointer!) there. So, we detect that + special case and encode it as a zero-length array. Try to detect that we are part of a struct. We do this by searching for '=' in the type encoding for the current type. Index: testsuite/ChangeLog =================================================================== --- testsuite/ChangeLog (revision 170370) +++ testsuite/ChangeLog (working copy) @@ -1,3 +1,8 @@ +2011-02-21 Nicola Pero + + PR objc/47832 + * objc.dg/type-size-4.m: New test. + 2011-02-21 Jeff Law PR rtl-optimization/46178 Index: testsuite/objc.dg/type-size-3.m =================================================================== --- testsuite/objc.dg/type-size-3.m (revision 170370) +++ testsuite/objc.dg/type-size-3.m (working copy) @@ -10,11 +10,9 @@ typedef struct @interface Test { - test_type c; + test_type c; /* { dg-error "instance variable .c. has unknown size" } */ } @end @implementation Test @end - -/* { dg-error "instance variable has unknown size" "" { target *-*-* } 0 } */ Index: testsuite/objc.dg/type-size-4.m =================================================================== --- testsuite/objc.dg/type-size-4.m (revision 0) +++ testsuite/objc.dg/type-size-4.m (revision 0) @@ -0,0 +1,20 @@ +/* Allow ivars that are pointers to structs with an unknown size. */ +/* Contributed by Nicola Pero */ +/* PR objc/47832 */ +/* { dg-do compile } */ + +typedef struct +{ + unsigned long int a; + double b[]; +} test_type; + +@interface Test +{ + /* This is fine. */ + test_type *c; +} +@end + +@implementation Test +@end