[PATCH v3] Revert __HAVE_64B_ATOMICS configure check

[Adhemerval Zanella Netto]

On 14/11/25 10:44, Wilco Dijkstra wrote:
> Hi Adhemerval,
> 
>> - Enable USE_64B_ATOMICS for x32.
> 
> That's incorrect. There is no guarantee that unaligned accesses are
> atomic even on x86.

I tend to agree, but this was it was historical done and I prefer to
*not* change now (and H.J already raised this as well).

I think it would be better to disable a 64-bit atomic on x32 on a
subsequent patch with a explanation on where it fails (since now
x32 glibc deployments are using it anyway).