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From:   =?UTF-8?Q?Maciej_=C5=BBenczykowski?= <maze@google.com>
Date:   Tue, 16 Jun 2020 03:19:15 -0700
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Subject: Re: [PATCH v2] [RFC] security: allow using Clang's zero
 initialization for stack variables
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     Alexander Potapenko <glider@google.com>,
        yamada.masahiro@socionext.com, Kees Cook <keescook@chromium.org>,
        jmorris@namei.org, Nick Desaulniers <ndesaulniers@google.com>,
        linux-security-module@vger.kernel.org,
        Kernel hackers <linux-kernel@vger.kernel.org>
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> Nit, your From: line of your email does not match your signed-off-by:
> line :(

This is *probably* a matter of configuring git:
git config --global user.name "Alexander Potapenko"
git config --global user.email "glider@google.com"
git config --global sendemail.from "Alexander Potapenko <glider@google.com>"

> Gotta love the name...

I've just read through a long discussion thread on clang dev (got
there from this cl's llvm link)...
There's a lot of interesting info in there.  But ultimately it seems
to point out tons of projects already use this or want to use it.
And there's security and stability benefits for production builds,
while pattern mode can be used for debug builds.

> Anyway, if this is enabled, and clang changes the flag or drops it, does
> the build suddenly break?

(my understanding of the patch is that the option does compiler
testing before it becomes available...
in at least some of our build systems built around kbuild the option
going away would then cause a build error due to its lack in the final
.config)

> And does gcc have something like this as well, or does that have to come
> in a compiler plugin?