Re: [PATCH 2/3] Makefile: use `find` to determine static header dependencies

From: Junio C Hamano <gitster@pobox.com>
Date: Aug 25, 2014, 19:30 UTC
Message-ID: <xmqqvbpgl638.fsf@gitster.dls.corp.google.com>
In-Reply-To: <20140822043303.GB18192@peff.net>

Jeff King <peff@peff.net> writes:

Show 11 quoted lines

> Since we do not use the value $(LIB_H) unless either
> COMPUTE_HEADER_DEPENDENCIES is turned on or the user is
> building "po/git.pot" (where it comes in via $(LOCALIZED_C),
> make is smart enough to not even run this "find" in most
> cases. However, we do need to stop using the "immediate"
> variable assignment ":=" for $(LOCALIZED_C). That's OK,
> because it was not otherwise useful here.
>
> Signed-off-by: Jeff King <peff@peff.net>
> ---
> I cannot see any reason for the ":=", but maybe I am missing something.

If the right-hand-side were something like $(shell find ...) that was heavy-weight then it might have made sense, but I do not think it is that. It has stayed to be := ever since it was introduced by cd5513a7 (i18n: Makefile: "pot" target to extract messages marked for translation, 2011-02-22).

And now you use LIB_H only once ;-).

Also interestingly, I notice that it is very clear that it is not "LIB_H" but "ANY_H" ;-)

Show 22 quoted lines

>
>  Makefile | 140 ++++-----------------------------------------------------------
>  1 file changed, 8 insertions(+), 132 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index cf0ccdf..f2b85c9 100644
> --- a/Makefile
> +++ b/Makefile
> ...
> @@ -2128,9 +2004,9 @@ XGETTEXT_FLAGS_C = $(XGETTEXT_FLAGS) --language=C \
>  XGETTEXT_FLAGS_SH = $(XGETTEXT_FLAGS) --language=Shell \
>  	--keyword=gettextln --keyword=eval_gettextln
>  XGETTEXT_FLAGS_PERL = $(XGETTEXT_FLAGS) --keyword=__ --language=Perl
> -LOCALIZED_C := $(C_OBJ:o=c) $(LIB_H) $(GENERATED_H)
> -LOCALIZED_SH := $(SCRIPT_SH)
> -LOCALIZED_PERL := $(SCRIPT_PERL)
> +LOCALIZED_C = $(C_OBJ:o=c) $(GENERATED_H)
> +LOCALIZED_SH = $(SCRIPT_SH)
> +LOCALIZED_PERL = $(SCRIPT_PERL)
>  
>  ifdef XGETTEXT_INCLUDE_TESTS
>  LOCALIZED_C += t/t0200/test.c