10077 usr/src/uts/ Makefile changes for smatch

@@ -20,10 +20,11 @@
 #
 #
 # Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 # Use is subject to license terms.
 #
+# Copyright (c) 2018, Joyent, Inc.
 
 #
 # This makefile drives the production of the rwd driver kernel module.
 #
 # i86pc architecture dependent

@@ -65,10 +66,13 @@
 LINTTAGS        += -erroff=E_BAD_PTR_CAST_ALIGN
 
 CERRWARN        += -_gcc=-Wno-uninitialized
 CERRWARN        += -_gcc=-Wno-unused-value
 
+# needs work
+SMOFF += return_cast
+
 #
 #       Default build targets.
 #
 .KEEP_STATE: