From f6dd8af4f6d9c329bcfd47c6aeb3d0a8fe323990 Mon Sep 17 00:00:00 2001
From: Yong-Hao Zou <yonghaoz1994@gmail.com>
Date: Thu, 12 Aug 2021 12:06:33 +0800
Subject: [PATCH] Fix null pointer in amcl on_cleanup

---
 nav2_amcl/src/amcl_node.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/nav2_amcl/src/amcl_node.cpp b/nav2_amcl/src/amcl_node.cpp
index 0e4fc20911..f1c0a6e556 100644
--- a/nav2_amcl/src/amcl_node.cpp
+++ b/nav2_amcl/src/amcl_node.cpp
@@ -335,8 +335,10 @@ AmclNode::on_cleanup(const rclcpp_lifecycle::State & /*state*/)
   laser_scan_sub_.reset();
 
   // Map
-  map_free(map_);
-  map_ = nullptr;
+  if (map_ != NULL) {
+    map_free(map_);
+    map_ = nullptr;
+  }
   first_map_received_ = false;
   free_space_indices.resize(0);