Yes, there is a setting in php.ini called 'short_open_tag' that should be set to on
if you are using PHP prior to version 5.4.0
From the manual:
Note: This directive also affected the shorthand
<?=
before PHP 5.4.0, which is identical to<?
echo. Use of this shortcut required short_open_tag to be on. Since PHP 5.4.0,<?=
is always available.