[Libunwind-devel] libunwind-ptrace and UNW_REMOTE_ONLY

[Ken Werner]

Hi,

I noticed that for unwinding via DWARF debug frames libunwind-ptrace 
relies on the local_addr_space [1] which is not initialized in case of 
UNW_REMOTE_ONLY [2]. This leads to a segfault in case CONFIG_DEBUG_FRAME 
is defined. So, I'm wondering if there is a nice way to fix this. As a 
workaround I defined the local_addr_space even if UNW_REMOTE_ONLY is 
defined and set the find_proc_info, resume, and put_unwind_info 
accessors to NULL. Any suggestions are appreciated.

Thanks,
Ken

[1] src/ptrace/_UPT_find_proc_info.c:_UPTi_find_unwind_table calls 
dwarf_find_debug_frame that uses the local_address_space to read some 
DWARF values out of the locally mapped ELF image.
[2] see: src/*/Ginit.c