Re: [PATCH] meson: Adjust check for __int128_t

[Paolo Bonzini]

On 5/24/23 12:30, Peter Maydell wrote:
> On Tue, 23 May 2023 at 23:39, Richard Henderson
> <richard.henderson@linaro.org> wrote:
> > Remove the signed * signed check, leaving the signed * unsigned check.
> > This link test runs foul of -fsanitize=undefined, where clang-11 has
> > an undefined reference to __muloti4 to check for signed overflow.
>
> If you can't do a signed * signed multiply then that sounds
> to me like "int128_t doesn't work on this compiler". We
> specifically added this check to catch "some clang with
> -fsanitize=undefined don't actually correctly compile
> int128_t * int128_t" in commit 464e3671f9.

Oops, missed this reply before queuing (and will leave the patch aside 
until the discussion is over).

As long as -fsanitize=undefined is properly covered by CI and we don't 
need int128_t * int128_t multiplication, removing the test is ok IMO, 
though perhaps it should have a comment about why it's avoided.

Paolo