lib/PublicInbox/Inbox.pm | 1 +

diff --git a/lib/PublicInbox/Inbox.pm b/lib/PublicInbox/Inbox.pm
index 7d5e048363f4c854cd17940d9af3aec0efc55e84..02186dac717fa329b6fb508d8eeab2c18919bca0 100644
--- a/lib/PublicInbox/Inbox.pm
+++ b/lib/PublicInbox/Inbox.pm
@@ -421,6 +421,7 @@ 	check_inodes($self);
 	my $subs = $self->{unlock_subs} or return;
 	for (values %$subs) {
 		eval { $_->on_inbox_unlock($self) };
+		warn "E: $@ ($self->{inboxdir})\n" if $@;
 	}
 }