--- a/hotspot/src/share/vm/logging/logConfiguration.cpp	Wed Sep 07 09:20:10 2016 +0200
+++ b/hotspot/src/share/vm/logging/logConfiguration.cpp	Wed Sep 07 14:36:44 2016 +0200
@@ -385,6 +385,7 @@
                                            const char* decoratorstr,
                                            const char* output_options,
                                            outputStream* errstream) {
+  assert(errstream != NULL, "errstream can not be NULL");
   if (outputstr == NULL || strlen(outputstr) == 0) {
     outputstr = "stdout";
   }