10080 smatch Makefile changes for usr/src/cmd

@@ -19,18 +19,21 @@
 # CDDL HEADER END
 #
 # Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 # Use is subject to license terms.
 #
+# Copyright (c) 2018, Joyent, Inc.
 
 PROG=   strace strerr strclean
 
 include ../../Makefile.cmd
 
 CFLAGS += $(CCVERBOSE)
 CERRWARN += -_gcc=-Wno-unused-variable
 
+SMOFF += all_func_returns
+
 FILEMODE= 0555
 
 .KEEP_STATE:
 
 all: $(PROG)