On 24/11/2010 21:31, Joern Rennecke wrote:
> Quoting Paul Koning <paul_kon...@dell.com>:
>
>> If BITS_PER_UNIT is all that's left, could you use some genxxx.c to
>> extract that from tm.h and drop it into a tm-bits.h in the build
>> directory? Then you could include that one instead of tm.h.
>
> Yes, that's what I said. Only there is little point in writing
> the generator program right now if all it ever does is spit out
> #define BITS_PER_UNIT 8
>
> We can add the generator program when we (re-) add a word addressed
> target, or add a bit addressed one.
I do think that this goal is not so far off that we should actually
encourage new code to break it. I built gcc 4.5.0 based on a 24-bit word size
recently, just in order to get the driver to work and the actual compiler
itself to successfully init itself and compile an empty file without crashing,
and that proved entirely practical, so we might not be so far off as one might
assume. That shows that the core is already substantially independent from
the target, I think, and that we could go further with that independence.
cheers,
DaveK
