Re: [GIT PULL] Add two-byte cmpxchg emulation function for v7.4

[Bradley Morgan]

On 3 November 2026 18:19:23 GMT, "Paul E. McKenney" <paulmck@xxxxxxxxxx>
wrote:
>On Tue, Nov 03, 2026 at 03:03:47AM +0100, Jan Engelhardt wrote:
>> 
>> On Monday 2026-11-02 17:34, David Laight wrote:
>> >> 
>> >> I can get gcc-17.0.0-20261102 with no further command line options
>> >> to turn `atomic_compare_exchange_strong`+uint16 into some object code
>> >> that does not contain a call to libatomic, for sh2, sh3, sh4. Haven't
>> >> tried xtensa or the others.
>> >> Thus, is the patch really needed?
>> >
>> >Won't that need a big jump in the minimum supported compiler version?
>> 
>> 12.0.0-20210420 behaves the same. I just chose 17 because that was
>> convenient to try first.
>
>Are you also advocating ditching the single-byte cmpxchg() emulation?
>If the compiler really can handle this emulation for all sizes on all
>supported compilers on all affected architectures, that is actually not
>at all an unattractive approach.

Well that would be "not long lasting effort" 2024-2026... Hmm..

>
>							Thanx, Paul

--- Thanks!
https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@xxxxxxxxx/