Description

According to the documentation for opcache.jit, the value disable means "Completely disabled, cannot be enabled at runtime", and the value off means "Disabled, but can be enabled at runtime".

But if you put the following values in your php.ini:

zend_extension=opcache
opcache.jit=off
opcache.jit_buffer_size=64M

...then you try to enable at runtime inside a .php file:

<?php
ini_set('opcache.jit', 'tracing');

...then you will get this:

Warning: Cannot change opcache.jit setting at run-time (JIT is disabled)

This is the same result you get if you set opcache.jit=disable.

As far as I can tell, the problem is that the code is looking for the literal string off but since that value is handled specially by PHP's ini parser, the code will never actually see a value of off. (It will never see no or false either.)

PHP Version

PHP 8.3.7

Operating System

No response