Error: Implicit conversion from void*

I get this error when I try to compile the follow line of code:

ANSI C++ forbids implicit conversion from `void *' in argument passing

referring to:

UnregisterClass( "Window", wc.hInstance );//wc is a WNDCLASSEX

AHH...why won't it just work! And why does it say 'void *'; I don't even see that anywhere in the source or headers for the class.

void * = (roughtly) char * = byte *

Unless you are using a pointer to your winclass wc , then use wc->hInstance, I get no problem with MSVC 5 / 97 but I use C no ++.

It's because hInstance member of WNDCLASSEX is of type HANDLE which is internally defined as (void *). UnregisterClass () awaits HINSTANCE type as the second argument. This type is probably something else. ANSI C++ forces programmer to cast (void *) pointers to proper types before passing them as arguments. This line solves your problem:

UnregisterClass ( "Window", (HINSTANCE) wc.hInstance );

In MSVC 5 / 97

WNDCLASSEX hInstance is recorded as a HANDLE in the help but is declared as a HINSTANCE in its header.

Not that this helps anyone...

While it is true in VC++ 4 to 6, casting hInstance to HINSTANCE is
unneeded. Guest didn't state what version of compiler he has. There's no problem if it is Visual 5.

Thanks everybody! I got it working right now.