[Python-Dev] ctypes is in SVN now.

Tim Peters tim.peters at gmail.com
Thu Mar 9 21:43:38 CET 2006


[Thomas Heller]
> ...
> And I never had tried it before on a sparc machine - all the intel and ppc processors
> seem to have no problems with it.

Pentiums don't enforce "natural" alignment restrictions, but run much
slower on unaligned access (varying by specific chip model, and
generally more heavily penalized as time goes on).  In the good old
days, Pentium was one of dozens of competing architectures, and was
the oddball in catering to unaligned access.  Now it's eternal
"backward compatibility" with an early implementation accident.  Most
other architectures never catered to unaligned access, or did so only
at the cost of generating an interrupt so that kernel-mode software
could fake unaligned access.  Bottom line is that unaligned access
isn't portable and never was, and even on architectures where "it
works" it can be extremely expensive to use it.


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