Re: [RFA] MIPS/GDB: Fix the handling of MIPS16 thunks

["Maciej W. Rozycki" <macro@codesourcery.com>]

On Wed, 11 Apr 2012, Richard Sandiford wrote:

> > [Richard, I've cc-ed you as the MIPS port maintainer of GCC and binutils, 
> > the producers of MIPS16 and some other thunks covered here, in case you 
> > had anything to add, and just so that you know this issue is being 
> > addressed now.]
> 
> Sounds like great work, thanks.  Hope it goes in.

 Well, there's only this small issue of gdbarch_in_solib_return_trampoline 
-- it shouldn't be too hard to overcome. :)

> I don't really have anything constructive to say, but just out of
> curiosity: we "fixed" call/return stubs to have unwind information for
> GCC 4.7.  Do you happen to know whether the test passes with that change?

 I am not completely sure as I haven't tried it/got to 4.7 yet (you may 
remember I had troubles building the head of the tree; I saw you fixed 
that at some point, thanks), but it looks to me the generic trampoline 
stuff I rely on here is tangential to any particular frame unwinders (as 
long as they get their details right, of course, which may not necessarily 
be true in all cases, as it is with the heuristic unwinders), so it should 
keep working.  I'll see if I can get to verifying this soon.

 Did you actually add this unwind information for both the mips16.S pieces 
and the compiler generated bits (how about the PIC stubs produced by LD?)?  
Does that happen to address the problem I reported here:

http://gcc.gnu.org/ml/gcc-patches/2011-12/msg01067.html

?  Note that it's not a coincidence the function name there is the same as 
one of those I used in the test case posted here -- this GDB test case 
will fail without a fix for that GCC problem just like the test case I 
posted there did.

  Maciej