[PATCH] Fix DW_CFA_set_loc handling

[David Daney]

Eric Botcazou wrote:
> Jakub,
> 
> 
>>Recent http://gcc.gnu.org/PR22313 change (including gcc 4.1 branch) started
>>(unnecessarily) using DW_CFA_set_loc at the start of all FDEs, but
>>unfortunately linker .eh_frame optimizations didn't handle that well.
>>If FDE encoding is pc relative or linker is changing it from absptr
>>to pc relative, we need to adjust the DW_CFA_set_loc operand accordingly.
>>
>>Tested with make check on x86_64-linux, visual inspection of x86_64
>>readelf -wf libc.so.6 (this was seriously broken before) and visual
>>inspection of a hacked up test for absptr -> pcrel conversion.
> 
> 
> This sounds a bit frightening, not everyone can afford to use binutils 
> mainline with the 4.1.x compiler.  We already found a nasty fallout
>   http://gcc.gnu.org/ml/gcc-patches/2006-09/msg00285.html
> so the change seems to be really destabilizing at this point.
> 
> Would you be OK to jointly ask Roger to back it out on the 4.1 branch?
> 

This has already been 'fixed'.

See: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29132

David Daney.