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From: "gonzalo.gadeschi at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/112789] Missing clang __builtin_ctzs for short
Date: Sat, 02 Dec 2023 23:32:31 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D112789

--- Comment #6 from gnzlbg <gonzalo.gadeschi at gmail dot com> ---
Thanks for all the quick feedback!

> Also clang does not even document __builtin_ctzs anywhere ...

This builtin is documented in the list of clang bultins. You can find it by
using CTRL+F for the builtin, in that list,
https://clang.llvm.org/docs/LanguageExtensions.html, which is the first link
that Google reveals when searching for this exact builtin. Hope that helps.

> ok, and?

There is an HPC QCD app that was developed mostly using clang, and for whic=
h we
can't apply source code modifications, that we'd like to compile which GCC =
as
is, but currently doesn't due to this issue.=20

Does that make sense?


> You could just do:

Thanks for the workaround! We were already using something similar as a
temporary stopgap, but can't use that forever. Hope that makes sense!

Thanks!=