I die when I use the command /time set xxxxxxx on a world with gamerule dodaylightcycle false.

When I use the command /time set xxxxx, I die.

What I expected to happen was
Me not to die, but only for the time to be set.

What actually happened was
I died, and it text on the chat bar said:'RedstoneMaster93 fell out of the world'.

Steps to Reproduce:
1.create a superflat world on version 16w21b, and put the gamerule /gamerule DoDaylightCycle false in the word, in a "alwys active" and "unconditional" command block.
2.do /time set xxxxx multiple times.