llvm-gcc-4.2/gcc/testsuite/gcc.apple/block-assignweakgcivar.c

/* APPLE LOCAL file radar 5882266 */
/* { dg-do run } */
/* { dg-options "-mmacosx-version-min=10.5 -ObjC -fobjc-gc -framework Foundation" { target *-*-darwin* } } */

#import <Foundation/Foundation.h>
void * _NSConcreteStackBlock;

int GlobalInt = 0;
int GlobalInt2 = 0;

id objc_assign_weak(id value, id *location) {
    GlobalInt = 1;
    *location = value;
    return value;
}

id objc_read_weak(id *location) {
    GlobalInt2 = 1;
    return *location;
}

@interface Foo : NSObject {
@public
    void (^__weak ivar)(void);
}
@end
@implementation Foo
@end

//void (^GlobalVoidVoid)(void);

void (^__weak Henry)(void);

int main(char *argc, char *argv[]) {
    // an object should not be retained within a stack Block
    int i = 0;
    void (^local)(void);
    Foo *foo = [[Foo alloc] init];
    foo->ivar = ^ { | i | ++i; }; /* { dg-warning "has been deprecated in blocks" } */
    if (GlobalInt == 1) {
        printf("%s: success\n", argv[0]);
        exit(0);
    }
    else {
        printf("%s: problem with weak write-barrier assignment of ivar\n", argv[0]);
    }
    exit(1);
}