From 9f8b2124694ac1637198d9a336e2c97e79fd8c23 Mon Sep 17 00:00:00 2001 From: Michal Schmidt Date: Mon, 14 Sep 2015 20:32:17 +0200 Subject: [PATCH] basic: make sure argument of ELEMENTSOF is an array Using ELEMENTSOF on a pointer will result in a compilation error. --- src/basic/macro.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/src/basic/macro.h b/src/basic/macro.h index b9a24f639..e93d7f155 100644 --- a/src/basic/macro.h +++ b/src/basic/macro.h @@ -124,8 +124,11 @@ static inline unsigned long ALIGN_POWER2(unsigned long u) { return 1UL << (sizeof(u) * 8 - __builtin_clzl(u - 1UL)); } -#define ELEMENTSOF(x) (sizeof(x)/sizeof((x)[0])) - +#define ELEMENTSOF(x) \ + __extension__ (__builtin_choose_expr( \ + !__builtin_types_compatible_p(typeof(x), typeof(&*(x))), \ + sizeof(x)/sizeof((x)[0]), \ + (void)0)) /* * container_of - cast a member of a structure out to the containing structure * @ptr: the pointer to the member. -- 2.30.2