[Libunwind-devel] use_prev_instr breaking unwind - how to stop it?

[Doug Moore]

When unw_init_local uses common_init to set use_prev_instr, and then 
fetch_proc_info decrements ip, based on use_prev_instr, unw_step fails for me.

I’m putting a temp break point at the start of _dl_runtime_resolve, and when 
gdb gets there, I’m sending a signal to trigger a signal handler that invokes 
unw_step.  What happens, sadly, is that the instruction pointer is decremented, 
so the eh_frames search doesn’t find the right frame, so the step fails.

If only I could clear that use_prev_instr field.  So far, I don’t have any 
better choices than to hack the libunwind source and maintain my own local 
branch.  Are there any better ideas?

Doug