Sorry for reviving an old thread, but was there any progress on this topic?
With packages as dbus that breaks with FEATURES/USE="test" hand in hand with packages like dev-libs/gmp[1] there would really be nice to know if you are supposed to be screwed or helped by FEATURES/USE="test"... [1](from http://gmplib.org/) IMPORTANT INFORMATION FOR ALL GMP USERS: GMP is very often miscompiled! Please never use your newly compiled libgmp.a or libgmp.so without first running make check. If it doesn't complete without errors, don't trust the library. Please try another compiler release, or change optimisation flags until it works. If you don't have the skill to isolate the problem, please report it to us as if it was a GMP bug; else to the compiler vendor. (The compilers that cause most problems are HP's unbundled compilers and gcc, in particular Apple's gcc releases.) N.B. gcc 4.3.2 miscompiles GMP 4.3.x on 64-bit machines.
