[PATCH] Improve endian conversion in umac.c

[Thorsten Glaser]

On Tue, 8 Mar 2022, rapier wrote:

> +    UINT32 temp = *(UINT32 *)ptr;

Can you guarantee it’s aligned? Otherwise, SIGBUS. Maybe not on x86,
other platforms exist and enforce that though (x86’ll just slowdown).

> +    *(UINT32 *)ptr = (i >> 24) | ((i & 0x00FF0000) >> 8 )
> +                   | ((i & 0x0000FF00) << 8 ) | (i << 24);

Can you guarantee it’s aligned *and* not UB? Otherwise, a version of
GCC, possibly a future one, is guaranteed to miscompile that and
pinskia will tell you it’s a feature…

bye,
//mirabilos
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