LLVM libunwind is an implementation of the interface defined by the HP libunwind project. It was contributed Apple as a way to enable clang++ to port to platforms that do not have a system unwinder. It is intended to be a small and fast implementation of the ABI, leaving off some features of HP's libunwind that never materialized (e.g. remote unwinding).
acquired package info from repodata DB: repodata/1b484c8eb5b8229fba6b5a5b11fe895b7104760061a10c49a7af41194c2b52a2-primary.sqlite.bz2
Unversioned shared library for LLVM libunwind