Re: [PATCH] HID: simplify code in fetch_item()

From: Segher Boessenkool
Date: Tue Oct 15 2024 - 17:02:35 EST


On Tue, Oct 15, 2024 at 12:26:04PM -0700, Nathan Chancellor wrote:
> On Tue, Oct 15, 2024 at 11:28:26AM -0700, Dmitry Torokhov wrote:
> > Oh well, if our toolchain does not like "unreachable()" then we can
> > simply remove it - the switch does cover all possible values and the
> > "return" statement should be valid even if compiler somehow decides that
> > "switch" statement can be skipped.
> >
> > If you can send a patch that would be great.
>
> Done, thanks a lot for the input!
>
> https://lore.kernel.org/20241015-hid-fix-fetch_item-unreachable-v1-1-b131cd10dbd1@xxxxxxxxxx/

There also is -funreachable-traps, which the kernel might want to use
(with that option every builtin_unreachablei() is compiled to a trap
instruction, instead of that the compiler just thinks "Aha! This can
never happen!", and optimise based on that).


Segher