It turns out that coreutils is already an implicit input in the build
environment so I removed it from the inputs.o

(ins)efraim@3900XT ~/workspace/guix$ grep '/bin/echo' /gnu/store/q0bvlalzwm1iwdqgmyksxxcm06fhr1l2-global-6.6.5/bin/globash
# Use /gnu/store/57xj5gcy1jbl9ai2lnrqnpr0dald9i65-coreutils-8.32/bin/echo, because in some systems, built-in echo of /bin/sh
ECHO='/gnu/store/57xj5gcy1jbl9ai2lnrqnpr0dald9i65-coreutils-8.32/bin/echo'

Thanks! Patch pushed.

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