ref: d247a4947ccba430d36a7470b3da7fd9499fd08c dir: /tests/cc/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; }