I'm trying to see if the rust bootstrap process works on core-updates
and I was unable to build for i686-linux on x86_64 linux. I failed to
build xz, due to some assembly optimizations. It turns out that instead
of using i686 binaries it was using x86_64 binaries and targeting i686,
while passing flags saying it was i686.

It seems there are some other things which need another look. From the
PATH variable:
(ins)efraim@3900XT ~/workspace/guix-core-updates$ file /gnu/store/yf4y60dyvb5qca8ram5pvxp7ba7x0z2a-xz-5.2.5/bin/xz
/gnu/store/yf4y60dyvb5qca8ram5pvxp7ba7x0z2a-xz-5.2.5/bin/xz: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /gnu/store/xd4jlar0rjsvc921b32kn40vn01638hc-glibc-2.33/lib/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, stripped
(ins)efraim@3900XT ~/workspace/guix-core-updates$ file /gnu/store/1g3vhzaw78fi04q630swrz4s9yn4wsj2-grep-3.6/bin:/gnu/store/vrdmi9lnd663np8y5hcpxvgkl35v5sby-coreutils-8.32
/gnu/store/1g3vhzaw78fi04q630swrz4s9yn4wsj2-grep-3.6/bin:/gnu/store/vrdmi9lnd663np8y5hcpxvgkl35v5sby-coreutils-8.32: cannot open `/gnu/store/1g3vhzaw78fi04q630swrz4s9yn4wsj2-grep-3.6/bin:/gnu/store/vrdmi9lnd663np8y5hcpxvgkl35v5sby-coreutils-8.32' (No such file or directory)

The ones listed in the environmental file at the base of the build
listed x86_64 binaries.

-- 
Efraim Flashner   <efraim@flashner.co.il>   אפרים פלשנר
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