Re: [RFC PATCH] Makefile: create externcheck target

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

Hi Denton,

On Thu, 8 Oct 2020, Denton Liu wrote:

> In b199d7147a (*.[ch]: remove extern from function declarations using
> sed, 2019-04-29), we used sed to remove extern from function
> definitions. In order to help find and remove future instances of this,
> teach Makefile the `externcheck` target which runs the sed script
> included in that commit on all applicable source files.
>
> Signed-off-by: Denton Liu <liu.denton@gmail.com>
> ---
>
> Notes:
>     I run this target periodically to ensure that no new instances of extern
>     function definitions are introduced. Is this something that we want to
>     consider adding for real?

Sure, and then hook it up in `ci/run-static-analysis.sh`.

But maybe add it _after_ coccicheck-pending, and add it to the `.PHONY`
line that's just outside of this patch's context lines?

Ciao,
Dscho

P.S.: I am not really certain that the `\s` is portable, I do not see any
mention of it in
https://pubs.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap09.html#tag_09_03
and would therefore expect BSD sed not to handle this correctly. In any
case, the `-i` is _not_ portable, as BSD sed takes a mandatory argument
(see
https://stackoverflow.com/questions/5694228/sed-in-place-flag-that-works-both-on-mac-bsd-and-linux
for more details).

>
>  Makefile | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/Makefile b/Makefile
> index 5311b1d2c4..791faa24cf 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -2885,6 +2885,9 @@ COCCI_SOURCES = $(filter-out $(THIRD_PARTY_SOURCES),$(FOUND_C_SOURCES))
>  	fi
>  coccicheck: $(addsuffix .patch,$(filter-out %.pending.cocci,$(wildcard contrib/coccinelle/*.cocci)))
>
> +externcheck: $(filter-out $(THIRD_PARTY_SOURCES),$(filter %.c %.h,$(shell $(FIND_SOURCE_FILES))))
> +	sed -i 's/^\(\s*\)extern \([^(]*([^*]\)/\1\2/' $^
> +
>  # See contrib/coccinelle/README
>  coccicheck-pending: $(addsuffix .patch,$(wildcard contrib/coccinelle/*.pending.cocci))
>
> --
> 2.29.0.rc0.261.g7178c9af9c
>
>