diff --git a/src/coparun/runmem.c b/src/coparun/runmem.c
index 3522358..df809bc 100644
--- a/src/coparun/runmem.c
+++ b/src/coparun/runmem.c
@@ -39,7 +39,7 @@ int update_data_offs() {
         perror("Error: code and data memory to far apart");
         return 0;
     }
-    data_offs = data_memory - executable_memory;
+    data_offs = (int)(data_memory - executable_memory);
     return 1;
 }