diff --git a/opcodes/s390-dis.c b/opcodes/s390-dis.c
index 9838365..0d32d05 100644
--- a/opcodes/s390-dis.c
+++ b/opcodes/s390-dis.c
@@ -312,7 +312,7 @@
 	  info->fprintf_styled_func (info->stream, dis_style_text,
 				     "%c", separator);
 	  info->fprintf_styled_func (info->stream, dis_style_register,
-				     "%%v%i", val.u);
+				     "%%v%u", val.u);
 	}
       else if (flags & S390_OPERAND_AR)
 	{