diff --git a/drivers/sac/driver/init.c b/drivers/sac/driver/init.c
index 974b67a80bc..d11e6948a3f 100644
--- a/drivers/sac/driver/init.c
+++ b/drivers/sac/driver/init.c
@@ -18,7 +18,7 @@ DriverEntry(IN PDRIVER_OBJECT DriverObject,
             IN PUNICODE_STRING RegistryPath)
 {
     HEADLESS_RSP_QUERY_INFO HeadlessInformation;
-    ULONG InfoSize = sizeof(HeadlessInformation);
+    SIZE_T InfoSize = sizeof(HeadlessInformation);
     NTSTATUS Status;
     UNICODE_STRING DriverName;
     PDEVICE_OBJECT DeviceObject;