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Date:   Fri, 3 Jul 2020 15:25:23 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Paul E. McKenney" <paulmck@kernel.org>
Cc:     Marco Elver <elver@google.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Sami Tolvanen <samitolvanen@google.com>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Will Deacon <will@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Kees Cook <keescook@chromium.org>,
        clang-built-linux <clang-built-linux@googlegroups.com>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        linux-arch <linux-arch@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, linux-pci@vger.kernel.org,
        "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@kernel.org>
Subject: Re: [PATCH 00/22] add support for Clang LTO
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On Fri, Jul 03, 2020 at 03:13:30PM +0200, Peter Zijlstra wrote:
> > The prototype for GCC is here: https://github.com/AKG001/gcc/
> 
> Thanks! Those test cases are somewhat over qualified though:
> 
>        static volatile _Atomic (TYPE) * _Dependent_ptr a;     		\

One question though; since its a qualifier, and we've recently spend a
whole lot of effort to strip qualifiers in say READ_ONCE(), how does,
and how do we want, this qualifier to behave.

C++ has very convenient means of manipulating qualifiers, so it's not
much of a problem there, but for C it is, as we've found, really quite
cumbersome. Even with _Generic() we can't manipulate individual
qualifiers afaict.