Mono compiler very rarely crashes trying to compile AStarPath.Update() method. The crash can occur while pressing starting to play the scene or stopping it or switching between Visual Studio and Unity.

How to reproduce:
1. Open Unity
2. Load user submitted project
3. Work in big scenes(Pardam, Pardam_olli) doing playtesting, changing scripts, tabbing in and out of Unity
4. Investigate crash

Expected result: No crash ever happens
Actual result: Mono compiler crashes while compiling AStarPath.Update() method

It can take multiple hours to reproduce a single crash.
Crash doesn't seem to be affected by CPU load or amount of free memory.
Because of rare chance to trigger the crash, we were unable to track down the regressed version.