From b2fcb192a83a11e8fb87de220c34463b7c82e490 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9=20Santos?=
 <git-afsantos@users.noreply.github.com>
Date: Tue, 24 Apr 2018 15:41:33 +0100
Subject: [PATCH] Replaced DCL pattern with static variable. Fixes #1364
 (#1365)

---
 clients/roscpp/src/libros/connection_manager.cpp | 14 ++------------
 clients/roscpp/src/libros/poll_manager.cpp       | 14 ++------------
 clients/roscpp/src/libros/xmlrpc_manager.cpp     | 14 ++------------
 3 files changed, 6 insertions(+), 36 deletions(-)

diff --git a/clients/roscpp/src/libros/connection_manager.cpp b/clients/roscpp/src/libros/connection_manager.cpp
index 98789b66ae..19fdb90cce 100644
--- a/clients/roscpp/src/libros/connection_manager.cpp
+++ b/clients/roscpp/src/libros/connection_manager.cpp
@@ -40,20 +40,10 @@
 namespace ros
 {
 
-ConnectionManagerPtr g_connection_manager;
-boost::mutex g_connection_manager_mutex;
 const ConnectionManagerPtr& ConnectionManager::instance()
 {
-  if (!g_connection_manager)
-  {
-    boost::mutex::scoped_lock lock(g_connection_manager_mutex);
-    if (!g_connection_manager)
-    {
-      g_connection_manager = boost::make_shared<ConnectionManager>();
-    }
-  }
-
-  return g_connection_manager;
+  static ConnectionManagerPtr connection_manager = boost::make_shared<ConnectionManager>();
+  return connection_manager;
 }
 
 ConnectionManager::ConnectionManager()
diff --git a/clients/roscpp/src/libros/poll_manager.cpp b/clients/roscpp/src/libros/poll_manager.cpp
index 569b9c53c7..4910d24c50 100644
--- a/clients/roscpp/src/libros/poll_manager.cpp
+++ b/clients/roscpp/src/libros/poll_manager.cpp
@@ -33,20 +33,10 @@
 namespace ros
 {
 
-PollManagerPtr g_poll_manager;
-boost::mutex g_poll_manager_mutex;
 const PollManagerPtr& PollManager::instance()
 {
-  if (!g_poll_manager)
-  {
-    boost::mutex::scoped_lock lock(g_poll_manager_mutex);
-    if (!g_poll_manager)
-    {
-      g_poll_manager.reset(new PollManager);
-    }
-  }
-
-  return g_poll_manager;
+  static PollManagerPtr poll_manager = boost::make_shared<PollManager>();
+  return poll_manager;
 }
 
 PollManager::PollManager()
diff --git a/clients/roscpp/src/libros/xmlrpc_manager.cpp b/clients/roscpp/src/libros/xmlrpc_manager.cpp
index 1aee46b1a5..15175ff5e7 100644
--- a/clients/roscpp/src/libros/xmlrpc_manager.cpp
+++ b/clients/roscpp/src/libros/xmlrpc_manager.cpp
@@ -95,20 +95,10 @@ void getPid(const XmlRpcValue& params, XmlRpcValue& result)
 
 const ros::WallDuration CachedXmlRpcClient::s_zombie_time_(30.0); // reap after 30 seconds
 
-XMLRPCManagerPtr g_xmlrpc_manager;
-boost::mutex g_xmlrpc_manager_mutex;
 const XMLRPCManagerPtr& XMLRPCManager::instance()
 {
-  if (!g_xmlrpc_manager)
-  {
-    boost::mutex::scoped_lock lock(g_xmlrpc_manager_mutex);
-    if (!g_xmlrpc_manager)
-    {
-      g_xmlrpc_manager.reset(new XMLRPCManager);
-    }
-  }
-
-  return g_xmlrpc_manager;
+  static XMLRPCManagerPtr xmlrpc_manager = boost::make_shared<XMLRPCManager>();
+  return xmlrpc_manager;
 }
 
 XMLRPCManager::XMLRPCManager()