Strange behavior of bit-shift [duplicate]

问题

This question already has answers here:

Arithmetic right shift gives bogus result? (2 answers)

Is right shift undefined behavior if the count is larger than the width of the type? (2 answers)

Closed 4 years ago.

Can't understand behavior of this bit shift:

int container = 1;

cout<<(container>>32)<<endl;

If it's logical shift the output should be 0, but it's 1 instead, as if it was cyclic shift. When looking at disassembly I see that command used is SAR. Please explain this behavior to me.

回答1:

You shifted a 32-bit number by 32, which results in undefined behavior, and the resulting 1 is a coincidence.

来源：https://stackoverflow.com/questions/31794709/strange-behavior-of-bit-shift