Weird linker error in GCC + NULL

[K.I.L.E.R]

Is there something I should know?

I'm doing this:

#define NULL (void*)0x0

because NULL can be defined by 0's regardless of the type of zero and because a void type usually means that it's pointing to a type that really has no known type and stuff.

Normally I never have to do this, this is my first time under 1 file in my project, the rest of my files have a NULL type already defined, prehaps it has something to do with the 50 different libraries I use.

Anyway I thought MinGW has a definition of this crap by default?
Also do I have to manually add all the MinGW environment "\include" into my project or is it default?

Anyway I fixed an issue with the weird linker error and guess what?
I didn't change the code.
I just went around deleting things and played aorund and the error is fixed.
Why cannot GCC/MinGW/CodeBlocks be stable enough to use?

Now I cannot get my bloody thing to run. It refuses to run.
Bloody hell. No errors either.

See;

-------------- Build: default in KrunoLCD ---------------
Linking executable: KrunoLCD.exe
mingw32-g++.exe: -E or -x required when input is from standard input
Process terminated with status 1 (0 minutes, 0 seconds)
0 errors, 0 warnings

EDIT:
Fixed new build error.
When building I noticed it returned error code '1' I then remembered I hadn't finished my command line editing with compiler commands.
Sorry.