Your bug report

#52311: Flex and Bison are not built from source

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 52311@debbugs.gnu.org.

-- 
52311: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=52311
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