diff --git a/src/mame/drivers/mgavegas.c b/src/mame/drivers/mgavegas.c
index 2b7bc741a05..cb7fea91f96 100644
--- a/src/mame/drivers/mgavegas.c
+++ b/src/mame/drivers/mgavegas.c
@@ -488,7 +488,7 @@ void mgavegas_state::machine_reset()
 {
 
 	m_int=1;
-	m_custom_data=0xffffffffffffffffLL;
+	m_custom_data=U64(0xffffffffffffffff);
 	
 	m_old_ckmod=1;
 	m_old_emod=0;