Mac OS X comes with sed from FreeBSD, some scripting in Makefile is incompatible with that version of sed so we recommend you to install GNU sed. The easiest way is via [Homebrew](http://brew.sh/) like in:
Mac OS X comes with sed from FreeBSD, some scripting in Makefile is
incompatible with that version of sed so we recommend you to install
GNU sed. The easiest way is via [Homebrew](http://brew.sh/) like in: