Your bug report

#15941: 24.2; Shell-script mode's syntax highligting gets confused by shift (<<) operator like in '$((1 << 32))

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 15941@debbugs.gnu.org.

-- 
15941: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=15941
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