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

The language standard defines how the language behaves, not how compilers are required to be implemented. Optimization isn't mandated because it isn't always wanted. Compilers provide options so that the user can enable optimizations if they so desire them, and can likewise turn them off. Compiler optimization can affect the ability to debug code (it becomes harder to match C to assembly in a line-by-line fashion), so it makes sense to only perform optimization at the user's request.