Description:
------------
On Linux, using PHP 5.3.2-1ubuntu4 with Suhosin-Patch (cli) and FreeTDS 0.82-6build1 (it's a vanilla lucid install, fully up to date):

When executing stored procedures using the "EXEC" SQL statement, both PDOStatement->execute as well as PDO::query seem to have a memory leak. We found this while executing a stored procedure within a loop: memory usage just kept increasing till the memory limit was reached. Unsetting/nullyfing variables does not help.

The leak is not present (memory usage stays perfectly constant) when using a "SELECT" SQL statement (which returns the exact same results as the stored procedure).

I have a feeling PDO is maybe only clearing the memory when it deals with a "SELECT" statement, and it misses the fact that data can also come back through "EXEC" statements?

This bug might be slightly related to bug 50755.


Test script:
---------------
// $polyItemArray is populated with a list of 300 IDs (integers).
// We loop through the array, and execute a stored procedure during each iteration:
foreach( $polyItemArray as $polyItemKey => $polyItem) {
	echo date('H:i:s') . ' | Processing: ' . $polyItem['sgp_id'];

	$dbh->query('EXEC proc_map_get_sgp_polygons ' . $polyItem['sgp_id'], PDO::FETCH_ASSOC);

/*
        // Alternate way of calling the procedure using PDOStatement; same leak is present:
	$stmt = $dbh->prepare($sql);
	$stmt->setFetchMode(PDO::FETCH_ASSOC);
	$stmt->execute( array($polyItem['sgp_id']) );
	$stmt->closeCursor();
	unset($stmt);
*/

	unset($polyItemKey);
	unset($polyItem);
	echo ' memory usage: ' . memory_get_usage(). ' bytes'. PHP_EOL;
}

// When running the script, memory usage just keeps increasing.

Expected result:
----------------
I would expect the memory usage of the script to stay constant.

Actual result:
--------------
Memory usage just keeps increasing.