[cfe-dev] [libunwind] relation between llvm libunwind and nongnu libunwind

[Lei Zhang via cfe-dev]

Hi,

I'm currently maintaining the llvm-libunwind package in Gentoo Linux.
I noticed there're two libunwind's out there, one from llvm and the
other from nongnu.

I couldn't find much documentation on this topic. At a glimpse, these
two libs seem very similar yet not 100% same. Is llvm's libunwind
intended to be ABI compatible with nongnu's? or just to be
functionally equivalent to it?

To add to my confusion, I found libunwind's header unwind.h is also
internally defined by gcc/clang. I did some testing; it seems
gcc/clang's internal unwind.h just work with libunwind's library. So
what's the relation among those variants of unwind.h? Is it a good
idea to mix-use them?


Thanks,
Lei