Plus the next sentence in the standard (which I just downloaded) is very relevant:
The behavior is undefined if the right operand is negative, or greater than or equal to the length in bits of the promoted left operand.
So, undefined behaviour. 
Plus the next sentence in the standard (which I just downloaded) is very relevant:
The behavior is undefined if the right operand is negative, or greater than or equal to the length in bits of the promoted left operand.
So, undefined behaviour.