[gpderetta]

You could argue that the setb and ret are not part of the leap year check itself. For example if the compiled inlined the call into a caller doing:

    if(is_leap_year_fast()) {...}

Then the ret would obviously go away and the setb wouldn't be necessary as it could generate directly a conditional jmp from the result of the cmp.

[npendleton]

Hah, great point!