diff --git a/Source/cmSystemTools.cxx b/Source/cmSystemTools.cxx
index b6cd957ef..a6872f168 100644
--- a/Source/cmSystemTools.cxx
+++ b/Source/cmSystemTools.cxx
@@ -304,22 +304,12 @@ bool cmSystemTools::IsOn(const char* val)
 
 bool cmSystemTools::IsNOTFOUND(const char* val)
 {
-  int len = strlen(val);
-  const char* notfound = "-NOTFOUND";
-  const int lenNotFound = 9;
-  if(len < lenNotFound)
-    {
-    return false;
-    }
-  if(strncmp((val + (len - lenNotFound)), notfound, lenNotFound) == 0)
+  cmsys::RegularExpression reg("-NOTFOUND$");
+  if(reg.find(val))
     {
     return true;
     }
-  if(strcmp(val, "NOTFOUND") == 0)
-    {
-    return true;
-    }
-  return false;
+  return std::string("NOTFOUND") == val;
 }