diff --git a/Trigger/TrigAnalysis/TriggerMatchingTool/Root/MatchingTool.cxx b/Trigger/TrigAnalysis/TriggerMatchingTool/Root/MatchingTool.cxx
index 48e8caea582f2eb68cead64e04d84661633e9f76..d4f14209fa90962f993f8e9f1b89e11ecf06450b 100644
--- a/Trigger/TrigAnalysis/TriggerMatchingTool/Root/MatchingTool.cxx
+++ b/Trigger/TrigAnalysis/TriggerMatchingTool/Root/MatchingTool.cxx
@@ -37,7 +37,7 @@ namespace Trig {
   }
 
 #ifndef XAOD_STANDALONE
-  void MatchingTool::updateOutputLevel(Property& p) {
+  void MatchingTool::updateOutputLevel(Property& /*p*/) {
     impl()->msg().setLevel(msgLevel()); //pass on our message level to the matchingimplementation
   }
 #endif