lib/PublicInbox/Inbox.pm | 6 +++---

diff --git a/lib/PublicInbox/Inbox.pm b/lib/PublicInbox/Inbox.pm
index 3ba92c997f2c669911e4f6667f5576ff1cd4c613..1d5fc708ad28b2649cf5a2460bfcbba96c8f3eeb 100644
--- a/lib/PublicInbox/Inbox.pm
+++ b/lib/PublicInbox/Inbox.pm
@@ -216,11 +216,11 @@ }
 
 sub cloneurl {
 	my ($self) = @_;
-	($self->{cloneurl} //= do {
+	$self->{cloneurl} // do {
 		my $s = try_cat("$self->{inboxdir}/cloneurl");
 		my @urls = split(/\s+/s, $s);
-		scalar(@urls) ? \@urls : undef
-	}) // [];
+		scalar(@urls) ? ($self->{cloneurl} = \@urls) : undef;
+	} // [];
 }
 
 sub base_url {