From c8279a1d897e7fb801676c266f0dd7a473159194 Mon Sep 17 00:00:00 2001
From: Denis Blank <denis.blank@outlook.com>
Date: Thu, 24 Nov 2016 17:03:53 +0100
Subject: [PATCH] Fix a dangerous c-cast in the cpp codegen

---
 contributors.txt                                              | 1 +
 .../resources/org/antlr/v4/tool/templates/codegen/Cpp/Cpp.stg | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/contributors.txt b/contributors.txt
index c3b6eebe4..70ea141df 100644
--- a/contributors.txt
+++ b/contributors.txt
@@ -123,3 +123,4 @@ YYYY/MM/DD, github id, Full name, email
 2016/11/25, MrSampson, Oliver Sampson, olsam@quickaudio.com
 2016/11/29, millergarym, Gary Miller, miller.garym@gmail.com
 2016/11/29, wxio, Gary Miller, gm@wx.io
+2016/11/29, Naios, Denis Blank, naios@users.noreply.github.com
diff --git a/tool/resources/org/antlr/v4/tool/templates/codegen/Cpp/Cpp.stg b/tool/resources/org/antlr/v4/tool/templates/codegen/Cpp/Cpp.stg
index 07a90b91b..c5099c2fe 100644
--- a/tool/resources/org/antlr/v4/tool/templates/codegen/Cpp/Cpp.stg
+++ b/tool/resources/org/antlr/v4/tool/templates/codegen/Cpp/Cpp.stg
@@ -1048,8 +1048,8 @@ virtual antlrcpp::Any accept(tree::ParseTreeVisitor *visitor) override;
 VisitorDispatchMethod(method) ::=  <<
 
 antlrcpp::Any <parser.name>::<struct.name>::accept(tree::ParseTreeVisitor *visitor) {
-  if (dynamic_cast\<<parser.grammarName>Visitor*>(visitor) != nullptr)
-    return ((<parser.grammarName>Visitor *)visitor)->visit<struct.derivedFromName; format="cap">(this);
+  if (auto parserVisitor = dynamic_cast\<<parser.grammarName>Visitor*>(visitor))
+    return parserVisitor->visit<struct.derivedFromName; format="cap">(this);
   else
     return visitor->visitChildren(this);
 }