Minecraft crashes when you put a Oak wood slab 4 blocks over you
see image

What I expected to happen was...:
I do not know what to write here

What actually happened was...:
I do not know what to write here

Steps to Reproduce:
1.First build a 4 block high tower from an arbitrary material
2.Next, set a selectable wood slab on the upper ledge of top 4th block
3.If you than set the next slab Minecraft crashes