Re: Questions regarding __register_frame_info

[Andrew Haley <aph at redhat dot com>]

jacob navia writes:
 > Hi
 > 
 > I have now everything in place for dynamically register the
 > debug frame information that my JIT (Just in time compiler)
 > generates.
 > 
 > I generate a CIE (Common information block), followed by
 > a series of FDE (Frame Description Entries) describing
 > each stack frame. The binary code is the same as gcc uses,
 > the contents of my stuff are identical to the contents of
 > the .eh_frame information.
 > 
 > There are several of those functions defined in unwind-dw2-fde.c:
 > 
 > __register_frame_info
 > __register_frame_info_bases
 > __register_frame_info_table_bases
 > 
 > If I use the
 > __register_frame_info
 > stuff, nothing happens and the program aborts.
 > Using __register_frame_jnfo_table_bases seems to
 > work better since it crashes a little bit further with a
 > hard crash.

What happens in gdb?  Does the lookup access your unwinder data?  What
is it doing when it crashes?

 >  From the code of register_frame_info (in file unwind-dw2-fde.c)
 > that function just inserts the new data into a linked list, but it
 > does not do anything more. That is why probably it will never
 > work.
 > 
 > Could someone here explain me or tell me what to do exactly to register
 > the frame information?
 > 
 > This will be useful for all people that write JITs, for instance the 
 > Java people,
 > and many others.
 > 
 > Thanks in advance for your help, and thanks for the help this group
 > has provided me already

Sure, we're all interested, but we don't have your code.  Have you
traced through the throwing of an exception?

Andrew.