diff -wbBur Crypt-Blowfish-2.12.org/Blowfish.xs Crypt-Blowfish-2.12/Blowfish.xs
--- Crypt-Blowfish-2.12.org/Blowfish.xs	2000-11-30 09:25:21.000000000 +0300
+++ Crypt-Blowfish-2.12/Blowfish.xs	2013-05-20 15:31:52.481940353 +0400
@@ -63,8 +63,7 @@
 			output = sv_newmortal();
 		output_len = 8;
 
-		if (!SvUPGRADE(output, SVt_PV))
-			croak("cannot use output argument as lvalue");
+		SvUPGRADE(output, SVt_PV);
 
 		/* blowfish_crypt_8bytes(input, SvGROW(output, 8), ks, dir); */
 		/* HP-UX (HP cc) fix below, thanks Addi! */