(address . bug-guix@gnu.org)
Currently offloading can not make use of --fallback, if sources are gone
or otherwise marked as not available, the machine builds are offloaded
to does not fetch the sources.
Recent example is libxt: Running "guix build libxt" gave 410 gone. I
tried "guix build --fallback libxt", same behavior. Running "guix build
--fallback --no-build-hook libxt" succeeded.
Therefore I conclude that offloading has no possibility to deal with --fallback.
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