I'm doing a MagLev mod for Space Engineers, and all the rail pieces are just linked to the same 1x1 rail piece with array and curve modifiers.
I'd accidentally kept a curve piece linked to the original, so I tried to make a single copy. Doing so reproducibly crashes Blender.
This happens on Windows 7, 64-bit, 2.77, 2.78 and November 1 Nightly. I used an addon for Space Engineers modding, but the issue happens when it's disabled as well.
Steps to reproduce:
- Open attached (minimal) Blender file .
- On the tool panel on the right, click  to make a single-user copy. Blender crashes with Error: EXCEPTION_ACCESS_VIOLATION.
Interestingly, the crash does not happen if you delete the collision geometry on layer 2 first.