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Date:   Wed, 19 Oct 2022 14:35:15 -0600
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Kees Cook <keescook@chromium.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Segher Boessenkool <segher@kernel.crashing.org>,
        linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org,
        linux-arch@vger.kernel.org, linux-toolchains@vger.kernel.org,
        Masahiro Yamada <masahiroy@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: Re: [PATCH] kbuild: treat char as always signed
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On Wed, Oct 19, 2022 at 12:30:59PM -0700, Linus Torvalds wrote:
> The crypto code uses 'unsigned char *' a lot - which makes a lot of
> sense, since the crypto code really does work basically with a "byte
> array", and 'unsigned char *' tends to really be a good way to do
> that.

I wish folks would use `u8 *` when they mean "byte array".

Maybe the attitude should just be -- use u8 for bytes, s8 for signed
bytes, and char for characters/strings. Declare any use of char for
something non-stringy forbidden, and call it a day. Yes, obviously u8
and s8 are just typedefs, but they're a lot more explicit of intent.

Jason