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From:   Alexei Starovoitov <alexei.starovoitov@gmail.com>
Date:   Thu, 19 Nov 2020 09:04:57 -0800
Message-ID: <CAADnVQL8d5zKTE_TohUcGgKKp6K1Noo7M22t_hKYQjO_g0Mb0g@mail.gmail.com>
Subject: Re: violating function pointer signature
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Segher Boessenkool <segher@kernel.crashing.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Florian Weimer <fw@deneb.enyo.de>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Sami Tolvanen <samitolvanen@google.com>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Matt Mullins <mmullins@mmlx.us>,
        Ingo Molnar <mingo@redhat.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Dmitry Vyukov <dvyukov@google.com>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>, Yonghong Song <yhs@fb.com>,
        Andrii Nakryiko <andriin@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@chromium.org>,
        netdev <netdev@vger.kernel.org>, bpf <bpf@vger.kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        linux-toolchains@vger.kernel.org
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On Thu, Nov 19, 2020 at 6:59 AM Steven Rostedt <rostedt@goodmis.org> wrote:
> Linux obviously
> supports multiple architectures (more than any other OS), but it is pretty
> stuck to gcc as a compiler (with LLVM just starting to work too).
>
> We are fine with being stuck to a compiler if it gives us what we want.

I beg to disagree.
android, chrome and others changed their kernel builds to
"make LLVM=1" some time ago.
It's absolutely vital for the health of the kernel to be built with
both gcc and llvm.