Objc foundation

[Peter Wiehe]

Hello all gcc users,
I'm trying to use the Objective-C compiler of gcc on GNU/Linux (xubuntu if
that matters).
But the compiler doesn't find the import file Foundation/Foundation.h
I can't find information about this on the net.
Am I simply missing a compiler option telling gcc where to find the import
file?
Is the foundation a part of gcc?
Do I need GNUStep?

Kind regards
Peter Wiehe