When I tried to build www-client/firefox-44.0 with [system-libevent] USE flag, I got error included such message: /var/tmp/portage/www-client/firefox-44.0/work/firefox-44.0/ipc/chromium/src/base/message_pump_libevent.cc:29:15: error: '_EVENT_SIZEOF_PTHREAD_T' was not declared in this scope CHECK_EVENT_SIZEOF(PTHREAD_T, pthread_t); ^ Then I rebuilt dev-libs/libevent with "threads" use flag and Firefox was build successfully.
Apologies for missing this until now. I'll confirm, and ensure the dependency on dev-libs/libevent requires USE="threads" on the next version bump.
Problem is still present with firefox-51.0.1. mozconfig-v6.51.eclass needs to be fixed.
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