From: Jeff King Date: Tue, 09 Jul 2013 06:38:40 GMT Subject: Re: [PATCH] remote-http: use argv-array Message-ID: <20130709063840.GA8015@sigill.intra.peff.net> In-Reply-To: On Tue, Jul 09, 2013 at 08:05:19AM +0200, Bert Wesarg wrote: > > + argv_array_pushl(&args, "send-pack", "--stateless-rpc", "--helper-status"); > > missing NULL sentinel. GCC has the 'sentinel' [1] attribute to catch > such errors. Or use macro magic: > > void argv_array_pushl_(struct argv_array *array, ...); > #define argv_array_pushl(array, ...) argv_array_pushl_(array, __VA_ARGS__, NULL) Nice catch. We cannot use variadic macros, because we support pre-C99 compilers that do not have them. But the sentinel attribute is a good idea. Here's a patch. -- >8 -- Subject: [PATCH] argv-array: add sentinel attribute to argv_array_pushl This attribute can help gcc notice when callers forget to add a NULL sentinel to the end of the function. We shouldn't need to #ifdef for other compilers, as __attribute__ is already a no-op on non-gcc-compatible compilers. Suggested-by: Bert Wesarg Signed-off-by: Jeff King --- This is our first use of an __attribute__ that is not "noreturn" or "format". I assume this one should be supported on other gcc-compatible compilers like clang. argv-array.h | 1 + 1 file changed, 1 insertion(+) diff --git a/argv-array.h b/argv-array.h index 40248d4..e805748 100644 --- a/argv-array.h +++ b/argv-array.h @@ -15,6 +15,7 @@ void argv_array_pushf(struct argv_array *, const char *fmt, ...); void argv_array_push(struct argv_array *, const char *); __attribute__((format (printf,2,3))) void argv_array_pushf(struct argv_array *, const char *fmt, ...); +__attribute__((sentinel)) void argv_array_pushl(struct argv_array *, ...); void argv_array_pop(struct argv_array *); void argv_array_clear(struct argv_array *); -- 1.8.3.rc3.24.gec82cb9