Reproduction steps:

1. Open "Maze generator.zip" project
2. Open "MazeTest" scene
3. Enter and Exit Play mode until the Editor crashes (Usually 1-3 times)

Expected Result: The Scene always starts and runs
Actual Result: The Editor crashes

Reproduced with: 2018.1.0b1, 2017.3.0p1, 2017.2.1p1
Did not reproduce on: 2017.1.3f1("Vector2Int" struct was only implemented as of 2017.2)

Note:
Tested on Mac OS 10.13 and 10.11
Windows 10 doesn't crash but loads the scene for a longer amount of time than one would expect