Can not access install/index.php?mode=update

( ! ) Fatal error: Call to a member function get() on a non-object in E:\phpBB-development\htdocs\phpBB-git\3.1\phpBB\includes\auth\auth.php on line 39

Call Stack

#	Time	Memory	Function	Location

1	0.0015	631424	{main}( )	..\index.php:0

2	0.4806	11207832	module->load( )	..\index.php:227

3	0.4806	11209208	install_update->main( )	..\index.php:350

4	0.5120	11812952	phpbb_auth->acl( )	..\install_update.php:114