Gentoo's Bugzilla –
Attachment 371808 Details for
Bug 503534media-gfx/darktable-1.4.1-r1 - In file included from .../work/darktable-1.4.1/src/external/squish/clusterfit.cpp:27: /usr/lib/gcc/i686-pc-linux-gnu/4.7.3/include/xmmintrin.h:32:3: error: #error "SSE instruction set not enabled"