Re: [PATCH 2/2] Replace literal STRLEN_ #defines in refs.h with compiler evaluated expressions

From: Junio C Hamano <gitster@pobox.com>
Date: Sep 29, 2007, 16:58 UTC
Message-ID: <7vd4w1l872.fsf@gitster.siamese.dyndns.org>
In-Reply-To: <200709291400.13880.andyparkins@gmail.com>

Andy Parkins <andyparkins@gmail.com> writes:

Show 12 quoted lines

> Bill Lear pointed out that the following:
>
>  #define PATH_REMOTES             "remotes/"
>  #define STRLEN_PATH_REMOTES      8
>
> Could be replaced by the less error-prone
>
>  #define PATH_REMOTES "remotes/"
>  #define LIT_STRLEN(S) ((sizeof(S) / sizeof(S[0])) -1)
>  #define STRLEN_PATH_REMOTES LIT_STRLEN(PATH_REMOTES)
>
> which is what this patch does.

I do not think the above is wrong per se, but doesn't a good compiler optimize

	#define PATH_REMOTES	"remotes/"
	#define STRLEN_PATH_REMOTES strlen(PATH_REMOTES)

	... and much later in some *.c file that includes the
	... above and <string.h>

        foo = strlen(PATH_REMOTES)

anyway?