diff options
Diffstat (limited to 'include/linux/build_bug.h')
| -rw-r--r-- | include/linux/build_bug.h | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/include/linux/build_bug.h b/include/linux/build_bug.h index faeec7433aab..0fe5426f2bdc 100644 --- a/include/linux/build_bug.h +++ b/include/linux/build_bug.h @@ -58,4 +58,23 @@ */ #define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed") +/** + * static_assert - check integer constant expression at build time + * + * static_assert() is a wrapper for the C11 _Static_assert, with a + * little macro magic to make the message optional (defaulting to the + * stringification of the tested expression). + * + * Contrary to BUILD_BUG_ON(), static_assert() can be used at global + * scope, but requires the expression to be an integer constant + * expression (i.e., it is not enough that __builtin_constant_p() is + * true for expr). + * + * Also note that BUILD_BUG_ON() fails the build if the condition is + * true, while static_assert() fails the build if the expression is + * false. + */ +#define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr) +#define __static_assert(expr, msg, ...) _Static_assert(expr, msg) + #endif /* _LINUX_BUILD_BUG_H */ |