https://bugs.freedesktop.org/show_bug.cgi?id=110614
--- Comment #7 from raffarti@zoho.com --- While trying to use the coredump, I've noticed /usr/lib64/dri/radeonsi_dri.so was used, so I've tried checking Xorg process with lsof in the good build... turns out both /usr/lib64/dri/radeonsi_dri.so and /opt/mesa/lib64/dri/radeonsi_dri.so were listed. With bad builds, renaming /usr/lib64/dri results in kde working but glxgears and glxinfo failing, while symlinking it to opt makes everything fine. So, looks like there's something wrong with my setup rather than mesa itself. I'll keep investigating why this happens but I guess this is invalid anyway. Sorry for the trouble.