ref: b7c1a1272d3b24c5fdc3246ed10c0dc9c6f8bd31 dir: /tests/execute/0036-notneg.c/
int main() { int x; x = 4; if(!x != 0) return 1; if(!!x != 1) return 1; if(-x != 0 - 4) return 1; return 0; }