Re: [PATCH] rebase-interactive.c: silence format-zero-length warnings

From: Junio C Hamano <gitster@pobox.com>
Date: Mar 3, 2020, 14:20 UTC
Message-ID: <xmqqh7z5a5an.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <87196142-8473-7d19-4edd-7452eaefda1c@gmail.com>

Alban Gruin <alban.gruin@gmail.com> writes:

Show 8 quoted lines

>> Fixes the following warnings:
>> 
>> rebase-interactive.c: In function ‘edit_todo_list’:
>> rebase-interactive.c:137:38: warning: zero-length gnu_printf format string [-Wformat-zero-length]
>>     write_file(rebase_path_dropped(), "");
>> rebase-interactive.c:144:37: warning: zero-length gnu_printf format string [-Wformat-zero-length]
> ...
> On a tangent: what's wrong with empty format strings?

Those functions that are truly printf-like, such a call would be no-op and an indication of possible typo ("did you forget a %s or something?"), I presume.

But many of our functions that take printf-like format strings will do useful things even when an empty string is given, so the warning is unwanted.