gcc 3.4.2 cpu32 patch

Ralf Corsepius ralf_corsepius at rtems.org
Thu Nov 18 07:53:23 UTC 2004


On Thu, 2004-11-18 at 17:49 +1100, Chris Johns wrote:
> Ralf Corsepius wrote:
> > 
> > Correct me if I am wrong, but AFAIS, it would be sufficient to extend
> > RTEMS m68k score to using __mcoldfire__ and __mcpu32__.
> > 
> 
> No as m68k.h in the score has a check for 68020 before the other 
> processor checks and so RTEMS tries to use 68020 instructions in various 
> asm statements and the compiler correctly rejects them.
> 
> Placing the check for the 68020 last avoids the problem but I would like 
> to know if this is expected behavior before making that change.

OK. I have to admit, the rationale behind this change also isn't obvious
to me.

AFAIU, GCC now seems to interpret the cpu32 as a sub-variant of the
m68020, while RTEMS expects the cpm32 to be treated as a cpu-variant
neighboring the 68020.

So, we would have to reflect this change into rtems:
#if __mc68020__
#if __cpu32__
..
#else
#endif
#endif

Ralf





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