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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Petr Mladek' <pmladek@suse.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>
CC:     Marco Elver <elver@google.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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        Steven Rostedt <rostedt@goodmis.org>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        Alexander Potapenko <glider@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: RE: [PATCH v2 2/3] lib/vsprintf: Split out sprintf() and friends
Thread-Topic: [PATCH v2 2/3] lib/vsprintf: Split out sprintf() and friends
Thread-Index: AQHZycNoqz0YrpkIvk2kVFpZOdRD+K/hpuug
Date:   Wed, 9 Aug 2023 08:48:54 +0000
Message-ID: <900a99a7c90241698c8a2622ca20fa96@AcuMS.aculab.com>
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...
> If you split headers into so many small pieces then all
> source files will start with 3 screens of includes. I do not see
> how this helps with maintainability.

You also slow down compilations.

A few extra definitions in a 'leaf' header (one without any
#includes) don't really matter.
If a header includes other 'leaf' headers that doesn't matter
much.

But the deep include chains caused by a low level header
including a main header are what causes pretty much every
header to get included in every compilation.

Breaking the deep chains is probably more useful than
adding leaf headers for things that are in a header pretty
much everything in going to include anyway.

The is probably scope for counting the depth of header
includes by looking at what each header includes.

	David

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