Build log should always be verbose as per talk on dev-ML, please force it until some EAPI includes a fix for this. Other versions might be affected as well.
Created attachment 320354 [details] util-linux-2.20.1-r2:20120730-211904.log
Uses econf, correct place to fix this isn't in the ebuild.
I don't know why it was closed as INVALID, the bug is valid and --disable-silent-rules works as expected.
same reason as before. not interested.
When writing ebuilds, you should always check the build log, because the build system might ignore CC/CXX/LD/CFLAGS/LDFLAGS and such or add undesired flags by default. In order to analyze this and have complete information, in case someone reports a bug for your package, the build log must always be verbose. http://devmanual.gentoo.org/ebuild-writing/common-mistakes/index.html