Your bug report

#19630: error message when referencing non-existing output not helpful

which was filed against the guix package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 19630@debbugs.gnu.org.

-- 
19630: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=19630
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