diff --git a/qapi/qapi-dealloc-visitor.c b/qapi/qapi-dealloc-visitor.c
index a07b171..75214e7 100644
--- a/qapi/qapi-dealloc-visitor.c
+++ b/qapi/qapi-dealloc-visitor.c
@@ -132,7 +132,7 @@
 {
 }
 
-static void qapi_dealloc_type_size(Visitor *v, size_t *obj, const char *name,
+static void qapi_dealloc_type_size(Visitor *v, uint64_t *obj, const char *name,
                                    Error **errp)
 {
 }