Re: Runaway cron task on 2.5.63/4 bk?

Linus Torvalds
2003-03-11T23:38:06Z

On Tue, 11 Mar 2003, Andrew Morton wrote:
>
> 2.95.3 and 3.2.1 seem to do it right?

Well, they do, but your test case is wrong:

> long a;
> long b;
> long long c;
>
> void foo(void)
> {
> c = a * b;

This is just a 32*32->32 multiply, with a final sign extension to 64 bits.

You need to do

c = (long long) a * b;

to get a 32*32->64 multiply. And yes, gcc gets that case right.

Linus