diff --git a/contributors.txt b/contributors.txt
index 6348bfd02..55f5cb6e5 100644
--- a/contributors.txt
+++ b/contributors.txt
@@ -178,6 +178,7 @@ YYYY/MM/DD, github id, Full name, email
 2017/12/01, DavidMoraisFerreira, David Morais Ferreira, david.moraisferreira@gmail.com
 2017/12/01, SebastianLng, Sebastian Lang, sebastian.lang@outlook.com
 2017/12/03, oranoran, Oran Epelbaum, oran / epelbaum me
+2017/12/12, janlinde, Jan Lindemann, jan@janware.com
 2017/12/13, enessoylu, Enes Soylu, enessoylutr@gmail.com
 2017/12/20, kbsletten, Kyle Sletten, kbsletten@gmail.com
 2017/12/27, jkmar, Jakub Marciniszyn, marciniszyn.jk@gmail.com
diff --git a/runtime/Cpp/runtime/src/Parser.h b/runtime/Cpp/runtime/src/Parser.h
index 14a41ba9c..515f83548 100755
--- a/runtime/Cpp/runtime/src/Parser.h
+++ b/runtime/Cpp/runtime/src/Parser.h
@@ -272,7 +272,7 @@ namespace antlr4 {
     /// <seealso cref="#_ctx"/> get the current context.
     virtual void enterRule(ParserRuleContext *localctx, size_t state, size_t ruleIndex);
 
-    virtual void exitRule();
+    void exitRule();
 
     virtual void enterOuterAlt(ParserRuleContext *localctx, size_t altNum);
 
diff --git a/runtime/Cpp/runtime/src/atn/TokensStartState.h b/runtime/Cpp/runtime/src/atn/TokensStartState.h
index 7657ffb75..e534d04ee 100755
--- a/runtime/Cpp/runtime/src/atn/TokensStartState.h
+++ b/runtime/Cpp/runtime/src/atn/TokensStartState.h
@@ -14,7 +14,7 @@ namespace atn {
   class ANTLR4CPP_PUBLIC TokensStartState final : public DecisionState {
 
   public:
-    virtual size_t getStateType();
+    virtual size_t getStateType() override;
   };
 
 } // namespace atn
diff --git a/runtime/Cpp/runtime/src/tree/pattern/TagChunk.h b/runtime/Cpp/runtime/src/tree/pattern/TagChunk.h
index a39e34f23..3d0c9f8d8 100755
--- a/runtime/Cpp/runtime/src/tree/pattern/TagChunk.h
+++ b/runtime/Cpp/runtime/src/tree/pattern/TagChunk.h
@@ -70,7 +70,7 @@ namespace pattern {
     /// are returned in the form {@code label:tag}, and unlabeled tags are
     /// returned as just the tag name.
     /// </summary>
-    virtual std::string toString();
+    virtual std::string toString() override;
 
   private:
     /// This is the backing field for <seealso cref="#getTag"/>.
diff --git a/runtime/Cpp/runtime/src/tree/pattern/TextChunk.h b/runtime/Cpp/runtime/src/tree/pattern/TextChunk.h
index 3b828a84d..1cbc0ddb2 100755
--- a/runtime/Cpp/runtime/src/tree/pattern/TextChunk.h
+++ b/runtime/Cpp/runtime/src/tree/pattern/TextChunk.h
@@ -43,7 +43,7 @@ namespace pattern {
     /// The implementation for <seealso cref="TextChunk"/> returns the result of
     /// <seealso cref="#getText()"/> in single quotes.
     /// </summary>
-    virtual std::string toString();
+    virtual std::string toString() override;
   };
 
 } // namespace pattern