[Spot-announce] Spot 2.9.7 released

We are happy to announce the release of Spot 2.9.7. This is a maintenance release that fixes a handful of minor issues. You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.9.7.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. Note that versions from the 2.9.x branch are the last releases using C++14. We have already switched to C++17 for the development of the next major release. This release is already compatible with C++17, so users using Spot as a library should consider switching to C++17 already. Please direct any feedback to &lt;spot(a)lrde.epita.fr&gt;fr>. New in spot 2.9.7 (2021-05-12) Bugs fixed: - Some formulas using ->, <->, or xor were not properly detected as purely universal or pure eventualities. - autfilt --keep-states=... could incorrectly mention --mask-acc when diagnosing errors. - Work around GraphViz issue 1931, causing spurious failures in the test suite. - Miscelaneous documentation fixes.