uniform half4 colorRed, colorGreen;

struct S { int c; };

bool inner_test() {
    S x = S(1);
    S y = S(1);
    return x == y;
}

bool test(bool S) {
    return inner_test();
}

half4 main(float2 S) {
    return test(true) ? colorGreen : colorRed;
}