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Subject: Seg fault when using active_symbol_table called from userspace function.
From: markskilbeck@gmail.com (Mark Skilbeck)

Can you explain to me why the following causes a segfault:

[code]
PHP_FUNCTION(sample_var_a_exists)
{
	if (!zend_hash_exists(EG(active_symbol_table), "a", sizeof("a"))) {
		RETURN_BOOL(0);
	}
	RETURN_BOOL(1);
}
[/code]

Note: the segfault only occurs when the sample_var_a_exists function is 
called from within a userspace function:

[code]
$a = '';
var_dump(sample_var_a_exists()); // bool(true)

function x() {
     var_dump(sample_var_a_exists()); // segmentation fault
}

x();
[/code]

Thanks.