diff --git a/ext/phar/tests/gh17808.phpt b/ext/phar/tests/gh17808.phpt
index 28cb9a2e227..03e54ff264b 100644
--- a/ext/phar/tests/gh17808.phpt
+++ b/ext/phar/tests/gh17808.phpt
@@ -2,6 +2,7 @@
 GH-17808 (PharFileInfo refcount bug)
 --EXTENSIONS--
 phar
+zlib
 --FILE--
 <?php
 $fname = __DIR__.'/tar/files/Structures_Graph-1.0.3.tgz';