Enable -fomit-frame-pointer on i386

[Jan Hubicka]

> Jan Hubicka writes:
>  > Perhaps we can simply replace use of backtrace() in libjava by
>  > the Jakub's unwind based implementation to break the dependency on
>  > targets where unwind info shall be available (ia-64/x86-64/i386/s390 at
>  > least)
> 
> That's a good idea.  Bryce is working on such a patch, I believe.
> 
> In the meantime, this is what we do with x86-64 
> 
> in configure.in:
> 
> BACKTRACESPEC=
> case "${host}" in
>  x86_64*-*-linux*)
>     BACKTRACESPEC=-fno-omit-frame-pointer
>     ;;
> esac
> 
> And configure.host:
> 
>   x86_64-*)
> 	CHECKREFSPEC="%{m32:-fcheck-references}"
> 	sysdeps_dir=x86-64
> 	libgcj_flags="${libgcj_flags} -ffloat-store -fno-omit-frame-pointer"

I this still important?  x86-64 glibc can do unwinding without frame
pointer for some time already.  But this looks like good trick for i386
for time being.

Honza
> 
> Andrew.