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Date:   Fri, 4 Mar 2022 11:15:44 -0700
From:   Nathan Chancellor <nathan@kernel.org>
To:     Kees Cook <keescook@chromium.org>
Cc:     Masahiro Yamada <masahiroy@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Shuah Khan <shuah@kernel.org>, llvm@lists.linux.dev,
        linux-kbuild@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH v2] kbuild: Make $(LLVM) more flexible
Message-ID: <YiJXUL3zIik+4QDv@thelio-3990X>
References: <20220304170813.1689186-1-nathan@kernel.org>
 <202203041005.A3B985C@keescook>
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On Fri, Mar 04, 2022 at 10:09:03AM -0800, Kees Cook wrote:
> On Fri, Mar 04, 2022 at 10:08:14AM -0700, Nathan Chancellor wrote:
> > [...]
> > 
> > Update and reorder the documentation to reflect these new additions.
> > At the same time, notate that LLVM=0 is not the same as just omitting it
> > altogether, which has confused people in the past.
> 
> Is it worth making LLVM=0 actually act the way it's expected to?

I don't really see the point, omitting $(LLVM) altogether is simpler.
Why specify LLVM=0 if you want GNU tools, since it is the default?
However, I can look into changing that in a new revision or a follow up
if others disagree?

> > Link: https://lore.kernel.org/r/20200317215515.226917-1-ndesaulniers@google.com/
> > Link: https://lore.kernel.org/r/20220224151322.072632223@infradead.org/
> > Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
> > Suggested-by: Peter Zijlstra <peterz@infradead.org>
> > Signed-off-by: Nathan Chancellor <nathan@kernel.org>
> 
> Looks good; minor .rst nit below...
> 
> Reviewed-by: Kees Cook <keescook@chromium.org>
> 
> > [...]
> > -LLVM has substitutes for GNU binutils utilities. Kbuild supports ``LLVM=1``
> > -to enable them. ::
> > -
> > -	make LLVM=1
> > -
> > -They can be enabled individually. The full list of the parameters: ::
> > +LLVM has substitutes for GNU binutils utilities. They can be enabled individually.
> > +The full list of supported make variables: ::
> 
> ": ::" and "::" yield the same result. I think the latter is more
> readable in non-rendered form. *shrug*

Ack, I'll wait for other feedback before sending v3, unless there is
none and Masahiro does not mind fixing it up during application.

Thanks for the review!
Nathan