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Date:   Tue, 1 Mar 2022 16:53:32 -0800
From:   Fangrui Song <maskray@google.com>
To:     Kees Cook <keescook@chromium.org>
Cc:     Nick Desaulniers <ndesaulniers@google.com>,
        Peter Zijlstra <peterz@infradead.org>, x86@kernel.org,
        joao@overdrivepizza.com, hjl.tools@gmail.com, jpoimboe@redhat.com,
        andrew.cooper3@citrix.com, linux-kernel@vger.kernel.org,
        samitolvanen@google.com, mark.rutland@arm.com,
        alyssa.milburn@intel.com, mbenes@suse.cz, rostedt@goodmis.org,
        mhiramat@kernel.org, alexei.starovoitov@gmail.com,
        Masahiro Yamada <masahiroy@kernel.org>,
        Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        llvm@lists.linux.dev, Nathan Chancellor <nathan@kernel.org>
Subject: Re: [PATCH v2 01/39] kbuild: Fix clang build
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On 2022-03-01, Kees Cook wrote:
>On Tue, Mar 01, 2022 at 01:16:04PM -0800, Nick Desaulniers wrote:
>> Also, Kees mentions this is an issue for testing multiple different
>> versions of gcc, too.  There perhaps is a way to simplify the builds
>> for BOTH toolchains; i.e. a yet-to-be-created shared variable denoting
>> the suffix for binaries?  The primary pain point seems to be Debian's
>> suffixing scheme; it will suffix GCC, clang, and lld, but not GNU
>> binutils IIUC.
>
>Right. Though I think auto-detection still makes sense.
>
>If I do:
>
>	make CC=clang-12 LLVM=1
>
>it'd be nice if it also used ld.lld-12.

This transformation may be a bit magical.

On Debian, /usr/bin/clang-13 is a symlink to /usr/lib/llvm-13/bin/clang .
Will it be fine for the user to provide correct feasible PATH?

>> [...]
>> Just curious, what prefixes have you observed in the wild?
>
>For me, where ever I built clang, and "/usr/bin"
>
>-- 
>Kees Cook
>