diff --git a/src/afs/DARWIN/osi_machdep.h b/src/afs/DARWIN/osi_machdep.h
index 5a615cbc4c..ae6e02eb9b 100644
--- a/src/afs/DARWIN/osi_machdep.h
+++ b/src/afs/DARWIN/osi_machdep.h
@@ -33,6 +33,7 @@ typedef unsigned short etap_event_t;
 #include <sys/lock.h>
 #include <sys/user.h>
 #include <sys/vnode.h>
+#include <sys/kauth.h>
 #endif
 #include <kern/thread.h>
 
@@ -104,7 +105,7 @@ enum vcexcl { EXCL, NONEXCL };
 #define crref kauth_cred_get_with_ref
 #define crhold kauth_cred_ref
 #ifdef AFS_DARWIN100_ENV
-#define crfree(X) kauth_cred_unref(&X)
+static inline void crfree(kauth_cred_t X) { kauth_cred_unref(&X); }
 #else
 #define crfree kauth_cred_rele
 #endif