media-libs/imlib2 fails with USE="-*" and -Wl,--as-needed -Wl,--no-undefined due to missing -lm for a plugin.
Created attachment 196425 [details, diff] as-needed.patch
Created attachment 196427 [details, diff] imlib2-1.4.2-r1.ebuild.diff
as a dev, you really should be aware of proper patch management. that means creating a patch named "as-needed.patch" is certainly not acceptable. going beyond that, you should review this document: http://dev.gentoo.org/~vapier/clean-patches and to address the original issue, such a trivial change really shouldnt be done to the autotool source files, especially considering it alone needs to run a full autoreconf. a simple sed can accomplish the same exact thing without forcing significantly more build time overhead. http://sources.gentoo.org/media-libs/imlib2/imlib2-1.4.2-r1.ebuild?r1=1.6&r2=1.7