Your bug report

#52519: glibmm-2.64 propagates two different versions of libsigc++

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 52519@debbugs.gnu.org.

-- 
52519: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=52519
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