As seen in bug #55016 you risk leaving stale symlinks on the system if opengl-update is not run after unmerging one OpenGL implementation. Perhaps a friendly warning after unmerging is in order? I was thinking something along the lines of this in the nvidia-glx, ati-drivers, and mtxdrivers-pro ebuilds: pkg_postrm() { ewarn "Remember to run \"opengl-update\" to switch to a working OpenGL!" }
Personally, I think it should run opengl-update for you, just like nvidia drivers do now at install time. Anyone else have thoughts on this?
Yes, I though about that too. It would make sense if there was only one valid OpenGL implementation remaining. If there were more (like after an upgrade), it should only warn. Not that I think many people will have three or more implementations installed (since that seems invalid), but in that situation it might be dangerous to meddle. At any rate, something has to be done. Leaving stale links on the system is simply not an option.
I would suggest that it switch back to the default implementation (xorg, xfree) because anything is better than broken, and it would ignore any others around (ati, nvidia, mtx, etc). Since running opengl-update prints some info about the action, it also can serve as a warning.
Your comment does bring up some interesting points in combination with bug #55212, though.
Yes, bug #55212 is exactly the kind of situation I was worrying about initially. I still suggest a warning at unmerge time, and that may indeed be the only safe choice (without a whole lot of logic behind it). At least that way it'll be the user that breaks the system, not portage :-)
this is fixed in the latest ati and nvidia drivers. Thanks.
