Unit test crash on exit

Note: Google Test filter = TranslationUnitUpdaterSlowTest.UpdatesParseTimePoint*
[==========] Running 1 test from 1 test suite.
[----------] Global test environment set-up.
[----------] 1 test from TranslationUnitUpdaterSlowTest
[ RUN ] TranslationUnitUpdaterSlowTest.UpdatesParseTimePoint
[ OK ] TranslationUnitUpdaterSlowTest.UpdatesParseTimePoint (40 ms)
[----------] 1 test from TranslationUnitUpdaterSlowTest (40 ms total)

[----------] Global test environment tear-down
[==========] 1 test from 1 test suite ran. (40 ms total)
[ PASSED ] 1 test.
unittest: /home/marco/dev/llvm/tools/clang/lib/Frontend/PrecompiledPreamble.cpp:124: void

::TemporaryFiles::removeFile(llvm::StringRef): Assertion `WasPresent && "File was not tracked"' failed.