On Fri, Nov 03, 2006 at 06:09:39PM +0100, Mikulas Patocka wrote:
> >In gmane.linux.kernel, you wrote:
> >[]
> >>From: Andrew Morton <[email protected]>
> >>
> >>As Mikulas points out, (1 << anything) won't be evaluating to zero.
> >
> >How about integer overflow ?
>
> C standard defines that shifts by more bits than size of a type are
> undefined (in fact 1<<32 produces 1 on i386, because processor uses only 5
> bits of a count).
,--
|#include <stdio.h>
|int main(void) {
| unsigned int b = 1;
|
| printf("%u\n", (1 << 33));
| printf("%u\n", (b << 33));
| return 0;
|}
|$ gcc bit.c && ./a.out
`--
There *is* difference, isn't it?
> Mikulas
____
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
