--- a/DES.xs	2005-12-08 15:52:50.000000000 +0000
+++ b/DES.xs	2013-03-13 15:02:29.000000000 +0000
@@ -64,8 +64,7 @@
 			output = sv_newmortal();
 		output_len = 8;
 
-		if (!SvUPGRADE(output, SVt_PV))
-			croak("cannot use output argument as lvalue");
+		(void) SvUPGRADE(output, SVt_PV);
 
 		perl_des_crypt(input, SvGROW(output, output_len), (i32 *)ks, enc_flag);