lib/PublicInbox/LeiToMail.pm | 3 ++-

diff --git a/lib/PublicInbox/LeiToMail.pm b/lib/PublicInbox/LeiToMail.pm
index f0adc44f23e6088b13e40d43b01fec9fa1705c7d..8a2d9471f032f45f3d2efba36678c46d13f7f2a9 100644
--- a/lib/PublicInbox/LeiToMail.pm
+++ b/lib/PublicInbox/LeiToMail.pm
@@ -302,8 +302,9 @@ 		$dst .= 'cur/';
 		$rand = '';
 		do {
 			$final = $dst.$rand.$common.':2,'.$sfx;
-		} while (!link($tmp, $final) && $! == EEXIST &&
+		} while (!($ok = link($tmp, $final)) && $! == EEXIST &&
 			($rand = _rand.','));
+		die "link($tmp, $final): $!" unless $ok;
 		unlink($tmp) or warn "W: failed to unlink $tmp: $!\n";
 	} else {
 		my $err = "Error writing $smsg->{blob} to $dst: $!\n";