diff --git a/Source/cmMakefile.cxx b/Source/cmMakefile.cxx
index f288e8418..383e1e0b6 100644
--- a/Source/cmMakefile.cxx
+++ b/Source/cmMakefile.cxx
@@ -757,7 +757,11 @@ void cmMakefile::AddLinkLibraryForTarget(const char *target,
     }
   else
     {
-    cmSystemTools::Error("Attempt to add link libraries to non-existant target: ",  target, " for lib ", lib);
+    cmOStringStream e;
+    e << "Attempt to add link library \""
+      << lib << "\" to target \""
+      << target << "\" which is not built by this project.";
+    cmSystemTools::Error(e.str().c_str());
     }
 }