Your bug report

#51669: some patterns which should match 0x0 don’t do so

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

The explanation is attached below, along with your original report.
If you require more details, please reply to 51669@debbugs.gnu.org.

-- 
51669: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=51669
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