--- /dev/null
+--TEST--
+crash when query string has nested array keys
+--SKIPIF--
+<?php
+include "skipif.inc";
+php_version_compare(PHP_VERSION, "7.0.0-dev") or die("skip php<7");
+?>
+--FILE--
+<?php
+
+echo "Test\n";
+
+$q = new http\QueryString("a[0][0]=x&a[1][0]=x");
+printf("%s\n", $q);
+
+?>
+===DONE===
+--EXPECT--
+Test
+a%5B0%5D%5B0%5D=x&a%5B1%5D%5B0%5D=x
+===DONE===