Description:
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When PDO::FETCH_FUNC is used without passing the function name as additional argument, Apache crashes.

Reproduce code:
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<?
$pdo = new PDO("sqlite::memory:");
$pdo->query ("CREATE TABLE test (a integer primary key)");
$pdo->query ("select a from test")->fetchAll(PDO::FETCH_FUNC);


Expected result:
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no error

Actual result:
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Apache crashes.