From 2b6811eddb9f8bf3593013a242213f1963e96f1f Mon Sep 17 00:00:00 2001
From: Peter Johnson <johnson.peter@gmail.com>
Date: Fri, 1 Nov 2019 23:42:01 -0700
Subject: [PATCH] Fix null pointer dereference in C++ CommandScheduler (#2023)

Java has a null check that was missing in C++ when adding default commands.
---
 .../src/main/native/cpp/frc2/command/CommandScheduler.cpp       | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/wpilibNewCommands/src/main/native/cpp/frc2/command/CommandScheduler.cpp b/wpilibNewCommands/src/main/native/cpp/frc2/command/CommandScheduler.cpp
index 66885e17f8..7a12a86eb7 100644
--- a/wpilibNewCommands/src/main/native/cpp/frc2/command/CommandScheduler.cpp
+++ b/wpilibNewCommands/src/main/native/cpp/frc2/command/CommandScheduler.cpp
@@ -174,7 +174,7 @@ void CommandScheduler::Run() {
   // Add default commands for un-required registered subsystems.
   for (auto&& subsystem : m_subsystems) {
     auto s = m_requirements.find(subsystem.getFirst());
-    if (s == m_requirements.end()) {
+    if (s == m_requirements.end() && subsystem.getSecond()) {
       Schedule({subsystem.getSecond().get()});
     }
   }