#### setup_xfail Procedure ¶

Declares that the test is expected to fail on a particular set of configurations. The config argument must be a list of full three-part configure target name; in particular, you may not use the shorter nicknames supported by configure (but you can use the common shell wildcard characters to specify a range of triplets). The bugid argument is optional, and used only in the logging file output; use it as a link to a bug-tracking system such as GNATS.

Once you use `setup_xfail`, the `fail` and `pass` procedures produce the messages XFAIL and XPASS respectively, allowing you to distinguish expected failures (and unexpected success!) from other test outcomes.

> Warning

> Warning you must clear the expected failure after using setup_xfail in a test case. Any call to `pass` or `fail` clears the expected failure implicitly; if the test has some other outcome, e.g. an error, you can call `clear_xfail` to clear the expected failure explicitly. Otherwise, the expected-failure declaration applies to whatever test runs next, leading to surprising results.

> `setup_xfail config bugid`

`config`

  The config triplet to trigger whether this is an unexpected or expect failure.

`bugid`

  The optional bugid, used to tie this test case to a bug tracking system.