Created attachment 674170 [details]
segfault stack trace
downgrading mesa to 20.2.2 restores normal work of the darktable
segfault happens immediately after starting the app
The stack trace you have posted shows you use libOpenCL provided by Nvidia, which is no longer supported by Gentoo. Please make sure you use libOpenCL from either dev-libs/ocl-icd or dev-libs/opencl-icd-loader, then try again and let us know if the problem persists.
Thanks for pointing out.
I tried my best looking at https://wiki.gentoo.org/wiki/OpenCL to find a way to direct darktable to the /usr/lib64/libOpenCL.so that I have installed from the dev-libs/ocl-icd-2.2.12-r3 but I failed to grasp how I can control this behaviour.
Can you point me to the right direction? What changes should I do to my system to make it behave?
Just make sure your system is up to date, the current versions of virtual/opencl automatically pull in one of the two ICD loaders and said loaders now install their libOpenCL.so directly into /usr/$(get_libdir).
Oh, and if the problem persists disable USE=opencl on Mesa - it seems you have got it on and I vaguely recall having seen some mention of ongoing work on extending OpenCL support in that library to more modern Nvidia GPUs.
Closing due to lack of feedback for over a month.