Bug#711558: PR52306 (was Re: Bug#711558: gcc-4.8: [m68k] patch set 2)

[Matthias Klose <doko@debian.org>]

Am 23.08.2013 00:26, schrieb Thorsten Glaser:
> Matthias Klose dixit:
> 
>> yes, I do reject this.
> 
> I see. Would you please…
> 
>>> “for the time being”? If so, would you accept a patch
>>> that just disables -fauto-inc-dec on m68k *always*,
>>> even in the cases where it doesn’t ICE? (one-liner)
> 
> answer whether this would be considerable? (Untested,
> but should have the desired effect, right Mikael?)
> 
> --- a/src/gcc/common.opt
> +++ b/src/gcc/common.opt
> @@ -858,7 +858,7 @@ Common Report Var(flag_asynchronous_unwi
>  Generate unwind tables that are exact at each instruction boundary
>  
>  fauto-inc-dec
> -Common Report Var(flag_auto_inc_dec) Init(1)
> +Common Report Var(flag_auto_inc_dec) Init(0)
>  Generate auto-inc/dec instructions
>  
>  ; -fcheck-bounds causes gcc to generate array bounds checks.
> 
> Or maybe this one (although it’s got the malus that it can’t
> be re-enabled for testing):
> 
> --- a/src/gcc/config/m68k/m68k.c
> +++ b/src/gcc/config/m68k/m68k.c
> @@ -663,6 +663,8 @@ m68k_override_options_after_change (void
>        flag_schedule_insns_after_reload = 0;
>        flag_modulo_sched = 0;
>      }
> +  /* PR52306 */
> +  flag_auto_inc_dec = 0;
>  }
>  
>  /* Generate a macro of the form __mPREFIX_cpu_NAME, where PREFIX is the
> 
>> not many thanks for trying to sneak in this into the
>> Debian package.
> 
> I’m just forwarding what we use in production. This is
> really necessary right now to work around bugs with the
> GNU Chagrin Collection.
> 
> Apparently just always disabling optimisation is the
> way, not just when it is problematic…

I think, setting the flag for the option to 0 as the default, and applying this
for m68k only would be the second best option, provided that you cannot find out
how to implement Mikael's suggestion.

  Matthias