1 files changed, 1 insertions, 1 deletions
diff --git a/maintenance/update.php b/maintenance/update.php
index 4a748ba55138..209fc691447b 100755
--- a/maintenance/update.php
+++ b/maintenance/update.php
@@ -261,7 +261,7 @@ class UpdateMediaWiki extends Maintenance {
 		parent::validateParamsAndArgs();
 	}
 
-	private function formatWarnings( array $warnings ) {
+	private function formatWarnings( array $warnings ): string {
 		$text = '';
 		foreach ( $warnings as $warning ) {
 			$warning = wordwrap( $warning, 75, "\n  " );