Re: [PATCH 0/9] Add missing includes and forward declares

From: Junio C Hamano <gitster@pobox.com>
Date: Aug 13, 2018, 18:24 UTC
Message-ID: <xmqqr2j25dlm.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <20180811173406.GA9119@sigill.intra.peff.net>

Jeff King <peff@peff.net> writes:

> The rule in Git has always been that your very first include must
> always be "git-compat-util.h" or an equivalent header that includes it
> first (like "cache.h"). This is mentioned in CodingGuidelines.

Glad to see that you already have written the above so I don't have to ;-)

As things are slowly moving out of the so-far kitchen-sink "cache.h" into more specific subsystem headers (like object-store.h), we may actually want to tighten the "header that includes it first" part a bit in the future, so that 'git grep cache.h' would give us a more explicit and a better picture of what really depends on knowing what the lowest level plumbing API are built around.

> So I think the better test is a two-line .c file with:
>
>   #include "git-compat-util.h"
>   #include $header_to_check

But until that tightening happens, I do not actually mind the two-line .c file started with inclusion of cache.h instead of git-compat-util.h. That would limit the scope of this series further.

> I wonder if there's an easy way to check. I guess adding '-Dint=foo' to
> the command line, and then putting '#undef int' at the top of
> git-compat-util would catch just about any code the compiler sees that
> doesn't have git-compat-util included. :)

;-).