/* An indirect way to compute zero, for an external analysis to find out. */ #include int sum(const int x, const int y) { return x + y; } int add4(const int z) { return sum(z, 1) + 3; } int main() { int x = add4(1) - 5; /* should be zero */ if (x) { printf("Dead code."); } int y = getchar() < 0; /* can happen */ if (y) { printf("Not dead code."); } return 0; }