diff --git a/src/plugins/clangtools/clangtoolssettings.cpp b/src/plugins/clangtools/clangtoolssettings.cpp
index f66f35ff6fb..0441e93d6c8 100644
--- a/src/plugins/clangtools/clangtoolssettings.cpp
+++ b/src/plugins/clangtools/clangtoolssettings.cpp
@@ -28,7 +28,6 @@ const char parallelJobsKey[] = "ParallelJobs";
 const char preferConfigFileKey[] = "PreferConfigFile";
 const char buildBeforeAnalysisKey[] = "BuildBeforeAnalysis";
 const char analyzeOpenFilesKey[] = "AnalyzeOpenFiles";
-const char oldDiagnosticConfigIdKey[] = "diagnosticConfigId";
 
 static Id defaultDiagnosticId()
 {