In 14w18a if you try to place an Item Frame in your world, the game will crash. If you load a world with an IF in it, the game will crash.
If you want the crash report, check the attachments.
Linked issues
duplicates 1
Attachments
Comments 2
Duplicate of MC-54008 - If you have not, please use the search function in the future, to see if your bug has already been submitted. If you could not find the original report, please comment with the keywords you searched for.
Duplicate of MC-54008