diff --git a/scripts/singleuse.pl b/scripts/singleuse.pl
index b4cbe3ff4a..3ce5dda442 100755
--- a/scripts/singleuse.pl
+++ b/scripts/singleuse.pl
@@ -36,7 +36,7 @@
 use strict;
 use warnings;
 
-my $unittests;
+my $unittests="";
 if(@ARGV && $ARGV[0] eq "--unit") {
     $unittests = "tests/unit ";
     shift @ARGV;