1. Open the attached "ReproProject"
2. Click on "mesk200k1:defaukt1" GameObject in Hierarchy
3. Add a Cloth component to it in Hierarchy

Expected result: Cloth component gets added after a second or two
Actual result: Editor freezes after adding a Cloth component, is not responding for a few minutes

Regression introduced in - 2017.3.0a7
Reproducible with - 2017.3.0b4, 2017.3.0a7
Not reproducible with - 2017.3.0a6, 2017.2.0f3, 2017.1.2f1

Note: Happens with all of the models that have a bigger vertices/polygons count. Does not happen with a more simple models

Fixed in 2018.1.0a6