Firstly i would like to say thanks for everyone's response.
i was using a bad (older) version of gmp from back when i thought i was having compatibility issues, updating gmp to the second to latest version (5.1 series) works perfectly. I then had problems with the MPFR and MPC config.sub files which i found on gregorr musl-cross website.
Now im having problems during the MPC build. I pulled the patch from the github/smaeul/starch/master/pkgbuilds site for mpfr and that did not resolve the issue. The issue being that I am building code in /root/code/build/ and it looks in that directory for gmp but resorts to the source directory for mpfr in /root/code/gcc/mpfr/ Why is it doing this? A config/patch issue i missed?
Attached is the mpc config.log. you can see the issue i am referring to right at the top in the command line invocation which im pasting below. Is there a file i can edit to correct the invocation?
Invocation command line was
$ /root/code/gcc/mpc/configure --cache-file=./config.cache --disable-nls --disable-shared --enable-static --without-headers --with-newlib --disable-decimal-float --disable-libgomp --disable-libmudflap --disable-libssp --disable-libatomic --disable-libquadmath --disable-multilib --disable-bootstrap --disable-threads --prefix=/root/cross/tools/ --with-sysroot=/root/cross/ --enable-languages=c,lto --program-transform-name=s,y,y, --disable-option-checking --build=i686-pc-linux-gnu --host=i686-linux-musl --target=i686-linux-musl --srcdir=../../gcc/mpc --disable-shared --with-gmp-include=/root/code/build/./gmp --with-gmp-lib=/root/code/build/./gmp/.libs --with-mpfr-include=/root/code/gcc/mpfr --with-mpfr-lib=/root/code/build/./mpfr/.libs
Thanks,
Stephen