1 files changed, 1 insertions, 0 deletions
diff --git a/git-debrebase b/git-debrebase
index 8385ae4..3449ec3 100755
--- a/git-debrebase
+++ b/git-debrebase
@@ -1173,6 +1173,7 @@ sub cmd_new_upstream () {
     # parse args - low commitment
     my $spec_version = shift @ARGV;
     my $new_version = (new Dpkg::Version $spec_version, check => 1);
+    fail "bad version number \`$spec_version'" unless defined $new_version;
     if ($new_version->is_native()) {
 	$new_version = (new Dpkg::Version "$spec_version-1", check => 1);
     }