[PATCH] Teach CMake build system to run lit's own test suite

[Dan Liew via llvm-commits]

On 9 January 2016 at 21:51, JF Bastien <jfb at chromium.org> wrote:
>> Thanks. I'll try that configuration out and see if I can reproduce the
>> problem.
>>
>> Given that I won't be able to do this immediately and that there are
>> other tests failing under Windows too I've reverted this patch for now
>> in r257268.

I managed to reproduce your issue and I've fixed it in r257616. The
problem was that psutil with a version < 2 used a different API to
iterate over child processes which my implementation wasn't calling.

You can test that it now works locally by doing

```
$ cd utils/lit/
$ ./lit.py --timeout=1 tests/Inputs/shtest-timeout/infinite_loop.py
lit.py: lit.cfg:15: note: Using external shell
-- Testing: 1 tests, 1 threads --
TIMEOUT: per_test_timeout :: infinite_loop.py (1 of 1)
Testing Time: 1.03s
********************
Timed Out Tests (1):
    per_test_timeout :: infinite_loop.py

  Individual Timeouts: 1
```

Unfortunately I can't put my patch to run lit's tests as part of
LLVM's ``check-all`` back into trunk because I've not time to
investigate the failures under Windows yet.