I received a bug report from a machine running musl when building vtkloguru module[1].
After looking into this, I noticed, there’s some logic in KWSys which handles missing execinfo.h properly. The build log attached at the bug report also shows, that the file is not found. Shouldn’t loguru.cpp use this info and check for the file before trying to #include it?
Looks like upstream doesn’t handle musl. The code looks like the files in vtkloguru. I don’t know how Alpine handles patches, on Gentoo we don’t have the package available.
Upstream has an open issue for about 4 years on this[1] which isn’t yet resolved.