Indeed this is a problem, when attempting to build GCC in a Guix profile
with 'gcc-toolchain' installed. What you may do is create wrapper
binaries so that the Guix GCC's 'etc/profile' is only active if using the
Guix GCC (that is, when building your cross-GCC's compilers), but isn't
active (and therefore 'C_INCLUDE_PATH', 'CPLUS_INCLUDE_PATH',
'LIBRARY_PATH' etc. not defined) when your cross-GCC builds its target
libraries. This means, you have to invoke the Guix GCC from outside of
the Guix profile. Something like this:
$ guix install -p "$GUIX_GCC" gcc-toolchain
..., and then script something like:
rm -rf "$GUIX_GCC"_bin
mkdir "$GUIX_GCC"_bin
for f in "$GUIX_GCC"/bin/* "$GUIX_GCC"/sbin/*; do
f_=$(basename "$f")
case "$f" in
*/c++ \
| */g++ \
| */gcc \
| */*-c++ \
| */*-g++ \
| */*-gcc )
cat > "$GUIX_GCC"_bin/"$f_" <<EOF
#!/bin/sh
set -e
d=\$(dirname "\$0")
. "\$d"/../$GUIX_GCC/etc/profile
"\$d"/../$f "\$@"
EOF
chmod +x "$GUIX_GCC"_bin/"$f_"
;;
*)
ln -s ../"$f" "$GUIX_GCC"_bin/"$f_"
;;
esac
done
..., and instead of '"$GUIX_GCC"/bin/gcc' etc. then use
'"$GUIX_GCC"_bin/gcc' etc.
In my opinion, the Guix-profile-wide setting of these environment
variables (via Guix GCC's 'etc/profile') doesn't feel quite right -- but
I'm still new to Guix, so...
