Re: gcc-4.3 considers unaligned accesses on X86 as undefined

[Andi Kleen]

TÃrÃk Edwin <edwintorok@xxxxxxxxx> writes:

> At -O3 it generates vectorized code that  _relies_  on the fact that
> pointers are always aligned (unless you use packed attributes, etc.),
> and the resulting code crashes if the pointer is unaligned.  (-O3 -msse
> on 32-bit, and simply -O3 on 64-bit since -msse is default)

The 2.6 kernel disables SSE and MMX code generation explicitely.
2.4 should be also safe unless someone misguided recompiles it with -O3.

-Andi
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