I don't know if this is a bug or desired behaviour. Having a custom /etc/site-config.jam "hides" /usr/share/boost-build/site-config.jam installed by boost-build and with it the variant gentoorelease defined there. Emerging dev-libs/boost-1.52.0-r5 (and probably also 1.49.0-r2) fails early in the process with notice: could not find main target gentoorelease and finally: don't know how to make gentoorelease Maybe the ebuild could issue a warning that a custom /etc/site-config.jam is not supported or that the contents of the version installed by boost-build has to be merged into it. Reproducible: Always
+ 28 Apr 2014; Sergey Popov <pinkbyte@gentoo.org> boost-1.52.0-r6.ebuild, + boost-1.53.0-r1.ebuild, boost-1.54.0-r1.ebuild, boost-1.55.0-r1.ebuild: + Add apropriate die message on unsupported overriden site-config.jam, wrt bug + #456792. Thanks to Raimar Sandner <gentoo-bugzilla AT 404not-found.de> for + reporting this issue