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Date:   Wed, 6 Dec 2023 22:25:50 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>, tanzirh@google.com,
        Kees Cook <keescook@chromium.org>,
        Andy Shevchenko <andy@kernel.org>,
        linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org,
        Nick DeSaulniers <nnn@google.com>, llvm@lists.linux.dev
Subject: Re: [PATCH] lib/string: shrink lib/string.i via IWYU
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On Tue, Dec 05, 2023 at 01:39:47PM -0800, Nick Desaulniers wrote:
> Hmm...how does one know that linux/bits.h is the higher-level include
> of asm/bitsperlong.h?

I think this the wrong way of thinking.  In general we should always
avoid including asm/ headers unless there is no other way.  No other
way is not formalized right now, but I think the answer is roughly if
no linux/ headers includes that asm header.  This will probably give
a few wrong results at the moment, but it's probably worth fixing
them up.