Just because something generates native code does not mean it "runs as fast as C". Semantics of a particular language can force it to do more job without any ch

Just because something generates native code does not mean it "runs as fast as C". Semantics of a particular language can force it to do more job without any chance to optimize that away. For example, if you modify C compiler to make integer operations clamp at min/max rather than overflowing, it will always be times slower than original at number crunching, and there would be no way to overcome that.