right now dragonegg's gcc plugin is installed under /usr/lib so there can be only one instance of it even if one has multiple gcc versions installed, forcing an emerge when switching between gcc versions. i think it should be installed into `gcc -print-file-name=plugin` (e.g., /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.2/plugin) instead which would make its use also easier (-fplugin=dragonegg) in addition to being able to have it for more than gcc version at a time.
Last rites for sys-devel/dragonegg in progress, bug #543644
