Problems with _Unwind_Backtrace() vs signal handlers

[Geoffrey Keating]

Bryce McKinlay <mckinlay@redhat.com> writes:

> For a normal call, the IP returned by _Unwind_GetIP() is the return
> address for the frame above it - that is, the instruction following
> the "call" instruction. When unwinding through a signal handler,
> however, _Unwind_GetIP() returns a pointer to the faulting
> instruction.

Sounds like a bug in MD_FALLBACK_FRAME_STATE_FOR on your platform.
I'd suggest looking at the powerpc-darwin implementation for
an indication of how to get this right.