GCC can even eliminate non-tail recursion, such as with this piece of black magic: int factorial(int x) { if (x > 1) return x * factorial(x-1);

GCC can even eliminate non-tail recursion, such as with this piece of black magic: int factorial(int x) { if (x > 1) return x * factorial(x-1); else return 1; } will be optimized by GCC to int factorial(int x) { int result = 1; while (x > 1) result *= x--; return result; } (http://ridiculousfish.com/blog/posts/will-it-optimize.html http://ridiculousfish.com/blog/posts/will-it-optimize.html)