Torches on top of Stairs

I was able to place a torch on top of a stair if there was a block next to the location I was place a torch. When the torch received a block update it would break.

What I expected to happen was...:
Describe what you thought should happen here

What actually happened was...:
Describe what happened here

Steps to Reproduce:
1. Place any stair
2. place a block next to it and a block above that
3. place a torch on top of the stair
4. give the torch a block update