ref: ca543c97d5f35334bc9784a3b5c7c5a8fe7a8f8a 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; }