bitcoin/bitcoin — pull request #5038 by luke-jr (2014-10-03 19:01:17+00:00)
Title: Bugfix: Replace bashisms with standard sh to fix build on non-BASH systems

Note: I have not actually tested this on a non-BASH system yet.

Downstream Gentoo bug: https://bugs.gentoo.org/show_bug.cgi?id=524332