diff --git a/tools/yaml2obj/yaml2obj.cpp b/tools/yaml2obj/yaml2obj.cpp
index e64e3dc1d17..ead4b7a86b2 100644
--- a/tools/yaml2obj/yaml2obj.cpp
+++ b/tools/yaml2obj/yaml2obj.cpp
@@ -95,5 +95,6 @@ int main(int argc, char **argv) {
   if (Res == 0)
     Out->keep();
 
+  Out->os().flush();
   return Res;
 }