some newbie questions

Eric Norum norume at
Sat Feb 14 22:22:11 UTC 2004

On Feb 14, 2004, at 4:00 PM, sebastian ssmoller wrote:
> thx now i understand how it works. that was the missing piece of the
> puzzle :) thank you for that hint
> so you "map" the c struct to the memory as described there, right ?
> but what about padding bits the compiler could insert/add for
> optimization ? do we know that the gcc doesnt do it ? what about a
> different compiler or a newer version of gcc e.g. 3.2 (i read about the
> recommandation in the docs ...) ?

I tried to be careful to add explicit padding where necessary.   As 
long as the compiler uses the same sizes for its types (char=1, 
short=2, int=4, xxx*=4) I wouldn't expect problems.   There are several 
other places in the m68k RTEMS support that rely on the same 
size/alignment restrictions so if things break for m68360.h they'll 
break in a lot of places for a lot of people!
Eric Norum <norume at>
Advanced Photon Source
Argonne National Laboratory
(630) 252-4793

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