New comment by Sturmflut on void-packages repository

https://github.com/void-linux/void-packages/issues/21105#issuecomment-1229178884

Comment:
`BUILD_SSE2_CODEPATHS=OFF` should be set automatically by CMake. `USE_OPENMP=OFF` is undesirable if you have more than one CPU core.

As a Proof-of-Concept, I converted all the `#ifdef _OPENMP` to `#if defined(_OPENMP) && !defined(__aarch64__)` if they wrapped around a `#pragma omp simd`. The attached patch does this for the current darktable master. It builds with OpenMP on a Raspberry Pi 3 and runs in parallel on all four cores.

Obviously this has to be fixed first and foremost in GCC. If the OpenMP standard supports mixed types for OpenMP SIMD and GCC supports mixed types on other platforms, it definitely also should do so on AArch64.