Description:
------------
When compiled with --enable-maintainer-zts, having nested try-catch blocks may cause segfaults in some cases.

In the following code fragment, commenting out the outer try-catch block solves the segfault.

This DOES NOT HAPPEN when compiled with debug symbols.

This may be related to bug #32252 (for instance, if the index to $list is positive, crash does not occur).

Reproduce code:
---------------
class a implements ArrayAccess {
    function offsetExists ($offset) { return false; }
    function offsetGet ($offset) { return null; }
    function offsetSet ($offset, $value) { throw new Exception ("Oops"); }
    function offsetUnset ($offset) { }
}
function test () {
    try {
        $list = new a();
        $caught = 0;
        try {
            $list[-1] = 123;
        } catch (Exception $e) {
            $caught = 1;
        }
        if (!$caught)
            return false;
        return true;
    }
    catch (Exception $e) {
        return false;
    }
}
print test();

Expected result:
----------------
The output should be "1"

Actual result:
--------------
Segmentation fault.

PHP was compiled without debug symbols. The stack trace provided by gdb was:

#0  0x08184ecd in zend_hash_destroy (ht=0x8c579c08)
    at /root/php-5.0.3/Zend/zend_hash.c:524