On 19/06/14 10:19, Jeff King wrote: > On Wed, Jun 18, 2014 at 11:30:50PM +0100, Ramsay Jones wrote: > >> So, the patch below is a slight variation on the original patch. >> I'm still slightly concerned about portability, but given that it >> has been at least a decade since I last used a (pre-ANSI) compiler >> which had a problem with this ... > > For a while some people were compiling git with pretty antique > compilers, but I do not know if that is the case any more (Junio noted > recently that we have had trailing commas on arrays and enums in > builtin/clean.c for the past year, and nobody has complained). > > Maybe those systems have all died off, or maybe those people only > upgrade every few years, and we are due for an onslaught of portability > fixes soon. :) :-P You never know ... >> [I have several versions of the C standard that I can use to check >> up on the legalise, but I'm not sure I can be bothered! ;-) ] > > It was actually pretty easy to find. I only have C99, but "empty macro > arguments" are listed as one of the changes since C89 in the foreward. Ah yes, having prompted me to look, it took all of 2 minutes to find it in the C11 .pdf file I have right here ... >> diff --git a/alloc.c b/alloc.c >> index eb22a45..5392d13 100644 >> --- a/alloc.c >> +++ b/alloc.c >> @@ -18,9 +18,12 @@ >> >> #define BLOCKING 1024 >> >> -#define DEFINE_ALLOCATOR(name, type) \ >> +#define PUBLIC >> +#define PRIVATE static >> + >> +#define DEFINE_ALLOCATOR(scope, name, type) \ > > I am not sure offhand whether this is more portable or not (it would > depend on order of macro expansion, and I am not brave enough to read > through the preprocessor section of the standard carefully). I suspect it is _slightly_ more portable, but I wouldn't bet any money on it! I may take a look at the standard (it wouldn't be the first time I've looked this up), but it would not help in this situation anyway. The fact that a given compiler does/does-not conform to the standard is useless knowledge if we need to support them. > Quick > reading online suggests that it's OK, but that an extra level of macro > expansion would not be. And of course the Internet is never wrong. :) ;-) > I'm inclined to go with it, and deal with it later if we get a > portability complaint (at which point we are no worse off than we are > right now). Hmm, well my initial reaction was to send the more conservative patch first. I wasn't so worried about inlining the code from the macro (I doubt it will change), but I understand (and would often agree with) your concern. I would be happy with either solution, so I'll let yourself and Junio decide! (sloping shoulders, or what. :) ). ATB, Ramsay Jones -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html