[0.15.1] Connecting the ends of a train together causes hang

[GinjaNinja32]

Fairly self-explanatory; placing a train in such a way that you connect the back to the front (e.g. by placing the wagon in the indicated location on the below screenshot) causes the game to hang.

What did you do?
I extended a train around a circular track and connected the two ends together.
What happened?
The game hung and I had to kill the process with SIGKILL (SIGTERM didn't work).
What did you expect to happen instead?
Either to not be allowed to place the last wagon, or for the game to handle a circular train properly.

The first screenshot shows the rear of the final wagon clipping into the front of the train, but in my initial discovery of the bug (second screenshot), the two ends lined up perfectly; the issue seems to be with circular trains in general, with the exact positioning of the final wagon being irrelevant.

[kovarex]

The logical implication of the 0.15 bugfix that allowed to connect both sides of the vehicle when building it

[steinio]

You get literally a loop.

[quyxkh]

I think we have the first bug report for the new "Well, Don't Do That Then" category.

[HanziQ]

Fixed for 0.15.2