Re: Is it a bug when use “<<”if the operator is out of the size "0~63"

[Jonathan Wakely]

This question is not appropriate for this mailing list, questions
about using GCC should be sent to the gcc-help@gcc.gnu.org list,
please take any follow up there, thanks.

On 24 February 2012 08:34, Yang Yueming wrote:
>
> The result of xyz should be "0"，but it is "2468acf123579bc" ,same as  xyz = abc << 1,Why?

The C standard says it's undefined behaviour:

"If the value of the right operand is negative or is greater than or
equal to the width of the promoted left operand, the behavior is
undefined."