netlink: replace __NLA_ENSURE implementation

We already have BUILD_BUG_ON_ZERO() which I just hadn't found
before, so we should use it here instead of open-coding another
implementation thereof.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/netlink.h b/include/net/netlink.h
index f1db8e5..4c1e993 100644 (file)
--- a/include/net/netlink.h
+++ b/include/net/netlink.h
@@ -311,7 +311,7 @@ struct nla_policy {
 #define NLA_POLICY_NESTED_ARRAY(maxattr, policy) \
        { .type = NLA_NESTED_ARRAY, .validation_data = policy, .len = maxattr }
 
-#define __NLA_ENSURE(condition) (sizeof(char[1 - 2*!(condition)]) - 1)
+#define __NLA_ENSURE(condition) BUILD_BUG_ON_ZERO(!(condition))
 #define NLA_ENSURE_INT_TYPE(tp)                                \
        (__NLA_ENSURE(tp == NLA_S8 || tp == NLA_U8 ||   \
                      tp == NLA_S16 || tp == NLA_U16 || \