Description:
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The firebird PDO driver returns nothing, or null if it fails to connect - this is contradictory to what the PDO documentation says (should throw PDOException) and the behaviour of the other drivers.

Reproduce code:
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$conn = new PDO("firebird:dbname=localhost:test.fdb",
  'SYSDBA','wrong password');


Expected result:
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It should throw a PDOException, ideally with an explanation or error code.

Actual result:
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Returns NULL with no errors or warnings even with error_reporting(E_ALL)