https://bugs.freedesktop.org/show_bug.cgi?id=30402
--- Comment #1 from Andy Furniss lists@andyfurniss.entadsl.com 2010-09-27 10:05:43 PDT --- I am getting the same when building mesa with r600 gallium, with the autogen command -
--enable-debug --disable-egl --enable-gallium-r600 --enable-gallium-swrast --with-dri-drivers=r600,swrast
My radeon_drv.so gets overwritten so that the next startx fails with the error as reported.