diff --git a/src/plugins/projectexplorer/projectexplorer.cpp b/src/plugins/projectexplorer/projectexplorer.cpp
index c34c3d5476f..64cdb35e841 100644
--- a/src/plugins/projectexplorer/projectexplorer.cpp
+++ b/src/plugins/projectexplorer/projectexplorer.cpp
@@ -211,7 +211,6 @@ const char REMOVEFILE[]           = "ProjectExplorer.RemoveFile";
 const char DUPLICATEFILE[]        = "ProjectExplorer.DuplicateFile";
 const char DELETEFILE[]           = "ProjectExplorer.DeleteFile";
 const char RENAMEFILE[]           = "ProjectExplorer.RenameFile";
-const char DIFFFILE[]             = "ProjectExplorer.DiffFile";
 const char SETSTARTUP[]           = "ProjectExplorer.SetStartup";
 const char PROJECTTREE_COLLAPSE_ALL[] = "ProjectExplorer.CollapseAll";