Silence NNI_ASSERT warnings when building with NDEBUG
if (!(x)) \
nni_panic("%s: %d: assert err: %s", __FILE__, __LINE__, #x)
#else
-#define NNI_ASSERT(x) (0)
+#define NNI_ASSERT(x) ((void)(0))
#endif
// Returns the size of an array in elements. (Convenience.)
