diff --git a/lib/isc/include/isc/bit.h b/lib/isc/include/isc/bit.h
index d2cd6d9e71..a8b47e16bc 100644
--- a/lib/isc/include/isc/bit.h
+++ b/lib/isc/include/isc/bit.h
@@ -107,7 +107,7 @@ isc_rotate_right64(const uint64_t x, uint32_t n) {
 	return (x >> n) | (x << (64 - n));
 }
 
-#if __APPLE_CC__
+#if __APPLE_CC__ || (defined(__OpenBSD__) && defined(__clang__))
 
 /*
  * Apple compiler doesn't recognize size_t and uintXX_t types as same,