[php-src] Issue #21058: undefined behavior in basic_functions.c

Issue: https://github.com/php/php-src/issues/21058
Author: chongwick

### Description

The following code:

```php
<?php
$v_6790 = getcwd();
$v_6796 = 'Hello World!';
$v_6807 = var_dump($v_6796,);
$v_6794 = 3;
$v_6812 = error_log($v_6807,$v_6794,$v_6807,);
```

Resulted in this output:
```
string(12) "Hello World!"

Deprecated: error_log(): Passing null to parameter #1 ($message) of type string is deprecated in /home/w023dtc/treebugs/0eebb710140f44c53dfd.php.er on line 6
/home/w023dtc/nightly_php/php-src/ext/standard/basic_functions.c:1372:13: runtime error: member access within null pointer of type 'const zend_string' (aka 'const struct _zend_string')
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior /home/w023dtc/nightly_php/php-src/ext/standard/basic_functions.c:1372:13
```



### PHP Version

```plain
nightly
```

### Operating System

ubuntu 22.04