When I turn on smooth lighting, things start to get ugly.

This glitch hasn't started now, it been around for a LONG time, I just decided to report it now. Smooth lighting makes certain things look horribly ugly. cI have included a few screenshots that display the problem.

Screenshot 1 shows the lighting glitch with stairs and beds

Screenshot 2 shows the lighting bug with upside down stairs

Screenshot 3 shows the lighting bug where light shows through slabs on the top half of blocks

Screenshot 4 shows the lighting bug with upside down stairs from the back

Screenshot 4 shows the lighting bug where sides of buildings get dark even though they should be light