Description:
------------
The code below segfaults on PHP 5.X. I have a patch for that which I'll submit once there is also one for PHP 7.

For PHP 7 the first zend_call_function to the function that throws the exception does not return FAILURE, which makes detecting whether the function succeeded or not be a bit tricky.

The code that has the issue is here:
http://lxr.php.net/xref/PHP_5_6/ext/sqlite3/sqlite3.c#900

Adding a debug line of:
    printf("ret is %x, failure is %x, success is %x\n", ret, FAILURE, SUCCESS);

after the zend_call_function produces the output:
    ret is 0, failure is ffffffff, success is 0


It looks like someone had similar trouble in libxml:
http://lxr.php.net/xref/PHP_TRUNK/ext/libxml/libxml.c#607

Where they are testing "if (status != SUCCESS || Z_ISUNDEF(retval)) {" to see if the zend_call_function succeeded or not.

It should be able to test if the function call succeeded by the return value from zend_call_function right?


Test script:
---------------
<?php

function oopsFunction($a, $b) {
	echo "This is inside the callback.\n";
    throw new \Exception("oops $a $b");
}

$db = new SQLite3(":memory:");
$db->exec("CREATE TABLE test (col1 string)");
$db->exec("INSERT INTO test VALUES ('a1')");
$db->exec("INSERT INTO test VALUES ('a10')");
$db->exec("INSERT INTO test VALUES ('a2')");

try {
    $db->createCollation('NATURAL_CMP', 'oopsFunction');
    $naturalSort = $db->query("SELECT col1 FROM test ORDER BY col1 COLLATE NATURAL_CMP");
    while ($row = $naturalSort->fetchArray()) {
        echo $row['col1'], "\n";
    }
    $db->close();
}
catch(\Exception $e) {
    echo "Exception: ".$e->getMessage();
}

Expected result:
----------------
zend_call_function on line 863 should return FAILURE as the function threw an exception.

Actual result:
--------------
zend_call_function returns SUCCESS even though the function threw an exception.