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Date:   Tue, 15 Sep 2020 23:14:02 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Josh Poimboeuf <jpoimboe@redhat.com>
Cc:     Nick Desaulniers <ndesaulniers@google.com>,
        Rong Chen <rong.a.chen@intel.com>,
        kernel test robot <lkp@intel.com>,
        "Li, Philip" <philip.li@intel.com>, x86-ml <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        clang-built-linux <clang-built-linux@googlegroups.com>,
        Marco Elver <elver@google.com>
Subject: Re: [tip:x86/seves] BUILD SUCCESS WITH WARNING
 e6eb15c9ba3165698488ae5c34920eea20eaa38e
Message-ID: <20200915211402.GB14436@zn.tnic>
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On Tue, Sep 15, 2020 at 04:02:31PM -0500, Josh Poimboeuf wrote:
> panic() is noreturn, so the compiler is enforcing the fact that it
> doesn't return, by trapping if it does return.
> 
> I seem to remember that's caused by CONFIG_UBSAN_TRAP.

From IRC: yah, CONFIG_UBSAN_TRAP=y in that config. But why doesn't my
clang12 generate this ud2?

gcc doesn't do that either.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette