cpp sanity test failure on Athlon64 build

[randall]

Is this a bug, or do I have some compiler flag not set right?
I am attempting to build gmp-4.2.2 on an Athlon64 3200+ processor

so why is cpp failing the sanity test?

------------------------------------------------------------
randall at athlon:~/gmp-4.2.2> gcc --version
gcc (GCC) 4.2.1 (SUSE Linux)
Copyright (C) 2007 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

randall at athlon:~/gmp-4.2.2> cat /proc/version
Linux version 2.6.22.17-0.1-default (geeko at buildhost) (gcc version 4.2.1 (SUSE 
Linux)) #1 SMP 2008/02/10 20:01:04 UTC

This is a 64 bit Athlon processor
Athlon 64 3200+ processor x86_64 architecture

randall at athlon:~> uname -a
Linux athlon 2.6.22.17-0.1-default #1 SMP 2008/02/10 20:01:04 UTC x86_64 
x86_64 x86_64 GNU/Linux

randall at athlon:~/gmp-4.2.2> ./config.guess
athlon64-unknown-linux-gnu

------------ attempting to run configure ------------------

randall at athlon:~/gmp-4.2.2> ./configure

checking build system type... athlon64-unknown-linux-gnu
checking host system type... athlon64-unknown-linux-gnu
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether to enable maintainer-specific portions of Makefiles... no
checking ABI=64
checking compiler gcc -O2 -m64 ... yes
checking compiler gcc -O2 -m64  -mtune=k8... yes
checking for gcc... gcc
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables...
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ANSI C... none needed
checking how to run the C preprocessor... /lib/cpp
configure: error: C preprocessor "/lib/cpp" fails sanity check
See `config.log' for more details.