In either C or C++, should I check pointer parameters against NULL/nullptr?

Question

This question was inspired by this answer.

I\'ve always been of the philosophy that the callee is never responsible when the caller does something stupid, like passi

Answer 1

The answer is going to be different for C and C++.

C++ has references. The only difference between passing a pointer and passing a reference is that the pointer can be null. So, if the writer of the called function expects a pointer argument and forgets to do something sane when it's null, he's silly, crazy or writing C-with-classes.

Either way, this is not a matter of who wears the responsibility hat. In order to write good software, the two programmers must co-operate, and it is the responsibility of all programmers to 1° avoid special cases that would require this kind of decision and 2° when that fails, write code that blows up in a non-ambiguous and documented way in order to help with debugging.

So, sure, you can point and laugh at the caller because he messed up and "everything not defined is undefined" and had to spend one hour debugging a simple null pointer bug, but your team wasted some precious time on that.