diff --git a/Source/cmCommand.h b/Source/cmCommand.h
index a34ea71939..66892434cf 100644
--- a/Source/cmCommand.h
+++ b/Source/cmCommand.h
@@ -155,7 +155,7 @@ public:
    */
   const char* GetError()
     {
-      if(this->Error.length() == 0)
+      if(this->Error.empty())
         {
         this->Error = this->GetName();
         this->Error += " unknown error.";