I am making some mines, in 1.9, and I was testing it, I went into survival, and it all worked, and I died. I went back into creative and tried to interact with the command blocks, but I couldn't, it wouldn't open, etc, when I re-logged, I could open the command blocks, and they acted like normal again.

To reproduce:
Place a command block, and execute /kill
go back to the command block, and try to interact with it. It won't work

I would add a video, but the video I prepared was laggy.