Your bug report

#12770: 24.2.1; sh-mode parsing - bitwise leftshift misinterpreted as here-document inside arithmetic expansion $(( ))

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 12770@debbugs.gnu.org.

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12770: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=12770
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