diff --git a/runtime/vm/service.cc b/runtime/vm/service.cc
index 7981794..d212875 100644
--- a/runtime/vm/service.cc
+++ b/runtime/vm/service.cc
@@ -4064,6 +4064,7 @@
 
 static const MethodParameter* request_heap_snapshot_params[] = {
     RUNNABLE_ISOLATE_PARAMETER,
+    NULL,
 };
 
 static bool RequestHeapSnapshot(Thread* thread, JSONStream* js) {