I have installed mingw32 on 64 bit Windows 7 using

mingw-get-inst-20110530.exe

I have been referred to http://sourceforge.net/projects/gmpmingw/
for a mingw32 binary version of GMP.

I have the following in my etc/profile file:

export PATH="/home/User/nano":$PATH;
export PATH="/home/User/":$PATH;
export PATH="/home/User/gmp-5.0.2":$PATH;

I need to get the following working:

GMP
MPFR
MPC

I am finding now that 

"C preprocessor /lib/cpp  is failing a sanity check." when I attempt to compile MPFR, with the aforementioned binary GMP.

Are there any mingw32 people who know what I need to do to my /lib/cpp to get it behaving better?

The advice I have so far doesn't help, and I have also installed the default C++ which comes with the exe installer I have.

I'm about to try the cpp from source, but apart from that, is there anyone out there with advice to solve the problem?