Your bug report

#21279: 24.4; (match-end 0) doesn't always return nil when previous string-match fails 

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

The explanation is attached below, along with your original report.
If you require more details, please reply to 21279@debbugs.gnu.org.

-- 
21279: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=21279
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