Re: [PATCH] difftool.c: mark a file-local symbol with static

[Junio C Hamano <gitster@pobox.com>]

Jeff King <peff@peff.net> writes:

> I don't have a preference on which direction we go, but yes, right now
> we are in an awkward middle ground. We should do one of:
>
>   1. Drop -Wno-format-zero-length from DEVELOPER_CFLAGS and make sure
>      future patches to do not violate it.
>
>   2. Declare warning("") as OK.
>
> I still think the warning is silly, but (1) has value in that it
> produces the least surprise and annoyance to various people building
> Git.

What is most awkward is that "make", with no customization out of
box, suggests to use -Wall in CFLAGS and triggers the misguided
warning, and DEVELOPER_CFLAGS, partly because it adds -Werror to
turn warnings (including this misguided one) into errors, disables
it with -Wno-format-zero-length.  As a result:

 - Casual builders that follow our suggestion get warnings.

 - Developers do not notice their new code may make the "casual
   builder" experience worse.

That is totally backwards.  That is probably what you meant by "the
least surprise and annoyance"?

I also still think that any_printf_like_function("%s", "") looks
silly.  I know that we've already started moving in that direction
and we stopped at a place we do not want to be in, but perhaps it
was a mistake to move in that direction in the first place.  I am
tempted to say we should do something like the attached, but that
may not fly well, as I suspect that -Wno-format-zero-length may be a
lot more exotic than the -Wall compiler option.  An obvious second
best option would be to drop -Wall from the "everybody" CFLAGS and
move it to DEVELOPER_CFLAGS instead.

diff --git a/Makefile b/Makefile
index a379738db2..137c10e257 100644
--- a/Makefile
+++ b/Makefile
@@ -391,10 +391,9 @@ GIT-VERSION-FILE: FORCE
 
 # CFLAGS and LDFLAGS are for the users to override from the command line.
 
-CFLAGS = -g -O2 -Wall
+CFLAGS = -g -O2 -Wall -Wno-format-zero-length
 DEVELOPER_CFLAGS = -Werror \
 	-Wdeclaration-after-statement \
-	-Wno-format-zero-length \
 	-Wold-style-definition \
 	-Woverflow \
 	-Wpointer-arith \