Re: PATCH] remove duplicate #include directives

["René Scharfe" <l.s.r@web.de>]

Am 06.10.19 um 01:41 schrieb Junio C Hamano:
> René Scharfe <l.s.r@web.de> writes:
>> This one here requires one more piece of information, though, namely our
>> convention of wrapping header files in guard defines to make repeated
>> includes of them no-ops.  We do that for those removed by the patch, but
>> we have a few exceptions to that rule in our repo (at least
>> command-list.h, kwset.h, sha1dc_git.h, tar.h, unicode-width.h).  So in
>> that sense it's not such a good example of a self-sufficient patch. :)
>
> Not really.  "We use header guards" is an argument that demotes this
> cleanup from "must have" to "nice to have".  If a project did not
> use header guards or including the same header twice were an error,
> the patch in question would have been more necessary, but that
> wouldn't have changed the correctness of the patch, I think.

You start with "No", but make my point -- a reader would need more
information than the content of the patch itself to classify it as a
trivial cleanup, namely knowledge of our use of include guards.

Here is an example of a non-idempotent header:

   #define NDEBUG
   ...
   #include <assert.h>
   ...
   #undef NDEBUG
   ...
   #include <assert.h>

(That's the only one we use that I'm aware of.)

René