[Bug target/53621] [SH] Frame pointers not generated with -fno-omit-frame-pointer on GCC 4.7.0

[lsebald1 at umbc dot edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53621

--- Comment #3 from Lawrence Sebald <lsebald1 at umbc dot edu> 2012-06-10 22:25:30 UTC ---
(In reply to comment #2)
> This line is related to PR 29996 and was introduced in this patch
> http://gcc.gnu.org/ml/gcc-patches/2010-01/msg01147.html
> 
> I'm not sure whether removing it won't introduce some other side effects.
> Maybe it should have been something like this instead?
> 
> flag_omit_frame_pointer = flag_omit_frame_pointer
>                           && (PREFERRED_DEBUGGING_TYPE == DWARF2_DEBUG);

That would probably make a bit more sense than just removing it entirely.
Although, it would probably be a good idea to put out a warning if the flag is
forcibly changed, just so people don't end up not knowing that the flag got
changed on them.

It does still seem odd to me that its switched on the preferred debugging
symbol format, since that may not actually represent the debugging symbol
format actually in use in the compiled code. I'm not all that familiar with GCC
internally, but I'd imagine there's some way to find out what debugging symbol
format is actually in-use to determine whether to change that flag or not.