PHP date function is not respecting date_default_timezone_set

Question

I'm trying to figure out why the date function is not respecting the default php timezone. This is my test script:

<?php

echo( "date_default_timezone_get: " . date_default_timezone_get(). "\n" );
echo( "date: " . date(DATE_RFC2822) . "\n" . "gmdate: " . gmdate(DATE_RFC2822) . "\n" );
echo( "date_default_timezone_set( 'UTC' ): " . date_default_timezone_set( 'UTC' ) . "\n" );
echo( "date: " . date(DATE_RFC2822) . "\n" . "gmdate: " . gmdate(DATE_RFC2822) . "\n" );
echo( "date_default_timezone_get: " . date_default_timezone_get() );
exit;

it's output is:

date_default_timezone_get: Europe/Rome
date: Thu, 08 Jul 2021 14:30:40 +0200
gmdate: Thu, 08 Jul 2021 12:30:40 +0000
date_default_timezone_set( 'UTC' ): 1
date: Thu, 08 Jul 2021 14:30:40 +0200
gmdate: Thu, 08 Jul 2021 12:30:40 +0000
date_default_timezone_get: UTC

As you can see, when I set the default timezone to UTC the date function won't change it's output

I'm using php fpm 7.4 on a debian 10 machine

> php -v
PHP 7.4.20 (cli) (built: Jun  4 2021 23:17:27) ( NTS )
Copyright (c) The PHP Group
Zend Engine v3.4.0, Copyright (c) Zend Technologies
    with Zend OPcache v7.4.20, Copyright (c), by Zend Technologies

Answer 1

Solved by updating to the minor version of PHP