diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py
index 73f136fc1d..eec5f1f4c5 100644
--- a/scripts/qapi-visit.py
+++ b/scripts/qapi-visit.py
@@ -115,6 +115,10 @@ out:
 
 
 def generate_visit_struct_body(name):
+    # FIXME: if *obj is NULL on entry, and visit_start_struct() assigns to
+    # *obj, but then visit_type_FOO_fields() fails, we should clean up *obj
+    # rather than leaving it non-NULL. As currently written, the caller must
+    # call qapi_free_FOO() to avoid a memory leak of the partial FOO.
     ret = mcgen('''
     Error *err = NULL;
 
diff --git a/tests/test-qmp-input-visitor.c b/tests/test-qmp-input-visitor.c
index b7a87ee351..a5cfefae8b 100644
--- a/tests/test-qmp-input-visitor.c
+++ b/tests/test-qmp-input-visitor.c
@@ -636,6 +636,8 @@ static void test_visitor_in_errors(TestInputVisitorData *data,
 
     visit_type_TestStruct(v, &p, NULL, &err);
     g_assert(err);
+    /* FIXME - a failed parse should not leave a partially-allocated p
+     * for us to clean up; this could cause callers to leak memory. */
     g_assert(p->string == NULL);
 
     error_free(err);