Bug#767803: Bug #767803: gdm3: After update Gdm3 displays "Oh No! Something has gone wrong"

[Rebecca N. Palmer]

Did the problem start when nvidia-libopencl1 and nvidia-opencl-icd were 
upgraded (check /var/log/apt/history.log)?  If so, this is probably the 
same bug as #769191 (see there for discussion of possible fixes): 
nvidia-opencl-icd just gained a dependency on libcuda1, which pulls in 
several other nvidia packages, including libgl1-nvidia-glx and 
glx-alternative-nvidia.