Your bug report

#17083: ‘union-build’ does not handle collisions between a leaf and a sub-tree

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 17083@debbugs.gnu.org.

-- 
17083: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=17083
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