gentoo-overlay/media-libs/raspberrypi-userland/files/raspberrypi-userland-9999-gentoo.patch

--- CMakeLists.txt.old	2015-02-20 19:37:32.754551301 +0100
+++ CMakeLists.txt	2015-02-20 19:38:45.643356903 +0100
@@ -38,6 +38,7 @@
 add_definitions(-DOMX_SKIP64BIT)
 add_definitions(-DEGL_SERVER_DISPMANX)
 add_definitions(-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64)
+add_definitions(-D_GNU_SOURCE)
 
 # do we actually need this?
 add_definitions(-D__VIDEOCORE4__)