I just noticed that there are two packages for libmpfr: https://packages.debian.org/sid/libmpfr4
https://packages.debian.org/sid/libmpfr6 Funny thing is, this is what the versioning says on those pages: Package: libmpfr4 (3.1.6-1) Package: libmpfr6 (4.0.1-1) ...ok, that's strange. Even weirder, they are both built from the same sources: mpfr-4.0.1-1. I feel like I'm missing something. For example, what does the "3.1.6-1" mean in libmpfr4? I assumed it was the underlying version but it can't be if it's built from the 4.0.1 sources? And why libmpfr6 when it's actually version 4 (there's no version 6 of mpfr).