[coreboot] buildgcc on Debian Stretch (9)

[Jonathan Neuschäfer]

Hi,

for a while now I've had problems using buildgcc on my Debian system,
which runs Debian testing (aka. stretch or version 9) and GCC 6.2. When
it fails, there is the following error in util/crossgcc/build-*-elf-GCC/config.log:

/usr/bin/ld: /home/jn/dev/coreboot/util/crossgcc/xgcc/lib/libgmp.a(fat_entry.o): relocation R_X86_64_32S against symbol `__gmpn_cpuvec' can not be used when making a shared object; recompile with -fPIC

This error only happens when buildgcc uses gcc 6.2. When I select gcc
4.9, gcc 5.3, clang 3.8, or clang 3.9, like this, buildgcc succeeds[1]:

CC=gcc-5 CXX=g++-5 make CPUS=3 crossgcc

Regards,
Jonathan Neuschäfer

[1]: You a little patch for buildgcc to accept $CC:
     https://review.coreboot.org/#/c/17931/