On 21 Oct 1998, Chris G. Demetriou wrote:

> Todd Vierling <tv@pobox.com> writes:
> > If this is possible, it should be turned on unconditionally.  SPARC has
> > alignment faults, and if the "rolling" is how ARM actually does unaligned
> > access, it should have alignment faults too.
> 
> Probably not desirable.

[snip]

Indeed - you can do all kinds of grotty optimisation with it.

It's quite possible that there's some intelesque code somewhere that
could cause this - we've recently found some code in a dhcpd that
gratuitously casts a char * to a long long *. The Alpha gibbers
slightly at this, since it wasn't aligned; there could well be a
non-aligned load that happens to work in x86 that's causing the same
kind of thing with ARM. Arguably gcc should be keeping half an eye out
for this kind of thing (although obviously it can't check every case).

-- 
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