Tee didn't print all output apparently, but it looks like someone forgot to "#include <dlfcn.h>" and when attempting to link OSMesa, it fails to link. The files it complains about not having it are the s3tc compression and glapi_gentable.
How would a missing header inclusion would cause a link issue ?
Either way thanks for reporting Aaron, but someone beat you to it :P Fix (revert) should be out shortly.
*** This bug has been marked as a duplicate of bug 82546 ***
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