diff --git a/Lib/test/regrtest.py b/Lib/test/regrtest.py
index 9c832215e4d..45880366ad3 100755
--- a/Lib/test/regrtest.py
+++ b/Lib/test/regrtest.py
@@ -230,7 +230,7 @@ def runtest(test, generate, verbose, quiet, testdir = None):
     outputfile = os.path.join(outputdir, test)
     try:
         if generate:
-            cfp = open(outputfile, "w")
+            cfp = StringIO.StringIO()
         elif verbose:
             cfp = sys.stdout
         else:
@@ -273,6 +273,24 @@ def runtest(test, generate, verbose, quiet, testdir = None):
             traceback.print_exc(file=sys.stdout)
         return 0
     else:
+        if generate:
+            output = cfp.getvalue()
+            if output == test + "\n":
+                if os.path.exists(outputfile):
+                    # Write it since it already exists (and the contents
+                    # may have changed), but let the user know it isn't
+                    # needed:
+                    fp = open(outputfile, "w")
+                    fp.write(output)
+                    fp.close()
+                    print "output file", outputfile, \
+                          "is no longer needed; consider removing it"
+                # else:
+                #     We don't need it, so don't create it.
+            else:
+                fp = open(outputfile, "w")
+                fp.write(output)
+                fp.close()
         return 1
 
 def findtestdir():