diff --git a/core/compat/solaris.h b/core/compat/solaris.h
index 249a193e..355b0aea 100644
--- a/core/compat/solaris.h
+++ b/core/compat/solaris.h
@@ -59,7 +59,7 @@
 
 // No u_int64_t on Solaris.
 #ifndef u_int64_t
-#define u_int64_t unsigned long long int
+typedef unsigned long long int u_int64_t;
 #endif
 
 #endif