From 1a1c52b967de67cce8c9c5eefab40b8ca7c106a4 Mon Sep 17 00:00:00 2001
From: Arnaud Giersch <arnaud.giersch@univ-fcomte.fr>
Date: Thu, 4 Apr 2019 14:48:23 +0200
Subject: [PATCH] Check validity for extension (Framagit issue #10).

---
 src/msg/msg_process.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/msg/msg_process.cpp b/src/msg/msg_process.cpp
index a3fcc834a0..b50cdb583f 100644
--- a/src/msg/msg_process.cpp
+++ b/src/msg/msg_process.cpp
@@ -30,7 +30,8 @@ void MSG_process_userdata_init()
 
   simgrid::s4u::Actor::on_destruction.connect([](simgrid::s4u::Actor const& actor) {
     // free the data if a function was provided
-    void* userdata = actor.extension<simgrid::msg::ActorUserData>()->get_user_data();
+    auto extension = actor.extension<simgrid::msg::ActorUserData>();
+    void* userdata = extension ? extension->get_user_data() : nullptr;
     if (userdata && msg_global->process_data_cleanup) {
       msg_global->process_data_cleanup(userdata);
     }
-- 
2.20.1