Unwind API was specifically designed to allow mixed language environments where exceptions from different runtimes interoperate. One particular example is C++/LuaJit combination. Due to the issues in libcxxrt, databases/tarantool crashes when linked against libcxxrt. Upstream accepted the patch: https://github.com/pathscale/libcxxrt/pull/32
Is this still relevant?
*** This bug has been marked as a duplicate of bug 204786 ***