From c8e857a0aff354ff6404e5f5e237796d98457fb2 Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Thu, 11 Dec 2008 11:19:01 +0000 Subject: [PATCH] Fix BUILD_BUG_ON() As was noticed on the Linux side, using an array here isn't appropriate if the condition is not a compile time constant - gcc allows such arrays, and hence the intended effect of producing a compiler error is not achieved in that case. Bit field widths do not know similar language extensions, and hence always produce a compiler error. Signed-off-by: Jan Beulich --- xen/include/xen/lib.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/xen/include/xen/lib.h b/xen/include/xen/lib.h index d6aa891eb9..cbadd0de15 100644 --- a/xen/include/xen/lib.h +++ b/xen/include/xen/lib.h @@ -16,7 +16,7 @@ void __warn(char *file, int line); #define WARN_ON(p) do { if (p) WARN(); } while (0) /* Force a compilation error if condition is true */ -#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2 * !!(condition)])) +#define BUILD_BUG_ON(condition) ((void)sizeof(struct { int:-!!(condition); })) #ifndef assert_failed #define assert_failed(p) \ -- 2.30.2