diff --git a/build/ck.build.s390x b/build/ck.build.s390x
index 6f353ed..5abec30 100644
--- a/build/ck.build.s390x
+++ b/build/ck.build.s390x
@@ -1,2 +1 @@
-CFLAGS+=-m64 -O0 -g
-LDFLAGS+=-m64
+CFLAGS+=-O2
diff --git a/include/gcc/s390x/ck_pr.h b/include/gcc/s390x/ck_pr.h
index dc3ddfa..8ad22b2 100644
--- a/include/gcc/s390x/ck_pr.h
+++ b/include/gcc/s390x/ck_pr.h
@@ -1,5 +1,6 @@
 /*
  * Copyright 2009-2015 Samy Al Bahra.
+ * Copyright 2017 Neale Ferguson
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without