C tail call optimization

Question

I often hear people say that C doesn\'t perform tail call elimination. Even though it\'s not guaranteed by the standard, isn\'t it performed in practice by any decent implement

Answer 1

For those who like proof by construction, here is godbolt doing a nice tail call optimisation and inline: https://godbolt.org/z/DMleUN

However, if you crank the optimization to -O3 (or no doubt if you wait a few years or use a different compiler), the optimisation totally removes the loop/recursion.

Here is an example that optimizes down to a single instruction even with -O2: https://godbolt.org/z/CNzWex