llvm-project/clang/test/SemaCXX/blocks-1.cpp

// RUN: %clang_cc1 -fsyntax-only -verify %s -fblocks

extern "C" int exit(int);

typedef struct {
    unsigned long ps[30];
    int qs[30];
} BobTheStruct;

int main (int argc, const char * argv[]) {
    BobTheStruct inny;
    BobTheStruct outty;
    BobTheStruct (^copyStruct)(BobTheStruct);
    int i;
    
    for(i=0; i<30; i++) {
        inny.ps[i] = i * i * i;
        inny.qs[i] = -i * i * i;
    }
    
    copyStruct = ^(BobTheStruct aBigStruct){ return aBigStruct; };  // pass-by-value intrinsically copies the argument
    
    outty = copyStruct(inny);

    if ( &inny == &outty ) {
        exit(1);
    }
    for(i=0; i<30; i++) {
        if ( (inny.ps[i] != outty.ps[i]) || (inny.qs[i] != outty.qs[i]) ) {
            exit(1);
        }
    }
    
    return 0;
}