NULL undeclared identifier in C++/CLI

Question

In my C++/CLI library, I am getting the compiler error:

error C2065: 'NULL' : undeclared identifier

Why is this happening? Note: I am setting the value of an unmanaged pointer to NULL, not a managed clr object pointer.

I know that I could just define NULL as 0, but that doesn't answer why this is suddenly happening. I am using NULL in other places, and things work fine.

If I add Windows.h to my stdafx.h include file, then I get warnings about a mismatch in the stdlib versions being linked with other dlls.

Why am I suddenly having issues using NULL?

Also, is it true that I can use nullptr for unmanaged types as well as managed?

EDIT: It seems that the answer to whether nullptr can be used for unmanaged types is yes. So I think that the answer is to just start using nullptr.

https://msdn.microsoft.com/en-us/library/4ex65770.aspx

Answer 1

you have to include stdlin.h or stddef.h, I believe