Probably just a buggy implementation. The C and C++ standards are explicit that `main` return an int and only an int. Never void. This has always been the case.

Probably just a buggy implementation. The C and C++ standards are explicit that `main` return an int and only an int. Never void. This has always been the case. However, the `main` function is the only function where the return statement can be omitted. If it is omitted, it’s an implicit `return 0`.