Amirite?
Signed-off-by: Alexey Zaytsev <alexey.zaytsev@xxxxxxxxx>
---
On Thu, Dec 25, 2008 at 21:36, Alexey Zaytsev <alexey.zaytsev@xxxxxxxxx> wrote:
> Tommy Thorn wrote:
>> Christopher Li wrote:
>>> So here is what I got. A patch address both of our need. It gives warning
>>> of using sizeof(void) explicitly. void* + offset will continue to work without
>>> warnings. It will also make is_byte_type() continue to work as it was
>>> before.
>>>
>>> Here is my test script:
>>>
>>> void *p;
>>>
>>> int i = sizeof(void);
>>> int j = sizeof(*p);
>>>
>
>> I can't test it right now, but does it give a warning for both sizeof's
>> above? If just first results in a warning, then I think that quite
>> reasonable.
>
> Both trigger the warning. I'm not sure this is a problem, as there are
> no such usage cases in the kernel.
>
> I added (hopefully the right way) handling of (sizeof(function)) to the
> patch. function++ was already prohibited.
>
> Running the test on the kernel right now.
>
And it found something.
2158a2159
> fs/compat_ioctl.c:787:10: warning: expression using sizeof on a function
9524a9526,9543
> drivers/media/video/gspca/sonixb.c:494:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:494:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:494:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:495:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:495:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:495:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:496:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:498:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:498:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:498:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:500:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:500:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:502:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:502:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:502:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:504:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:504:1: warning: expression using sizeof(void)
> drivers/media/video/gspca/sonixb.c:504:1: warning: expression using sizeof(void)
15293a15313,15325
> net/netfilter/nf_conntrack_sip.c:282:21: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:282:21: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:287:23: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:287:23: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:288:29: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:586:23: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:586:23: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:587:25: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:588:29: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:589:25: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:590:29: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:591:22: warning: expression using sizeof(void)
> net/netfilter/nf_conntrack_sip.c:591:22: warning: expression using sizeof(void)
The first one is
if (copy_in_user(&sgio->status, sgio32->status,
(4 * sizeof(unsigned char)) +
(2 * sizeof(unsigned (short))) + <------- oops
(3 * sizeof(int))))
return -EFAULT;
a bug. So, if anyone ever missed his sgio.info, now we know why.
Patch sent.
drivers/media/video/gspca/sonixb.c looks like
SENS(initHv7131, NULL, hv7131_sensor_init, NULL, NULL, 0, NO_EXPO|NO_FREQ, 0),
#define SENS(bridge_1, bridge_3, sensor, sensor_1, \
sensor_3, _flags, _ctrl_dis, _sensor_addr) \
{ \
.bridge_init = { bridge_1, bridge_3 }, \
.bridge_init_size = { sizeof(bridge_1), sizeof(bridge_3) }, \
So, we are getting a sizeof(NULL), or a sizeof((void *)0). It triggers here
because we are getting a null_ctype, and it's base_type points to
void_ctype. I'm not sure if this patch is correct, but it seems to do
the trick, all void warnings are gone. Christopher?
symbol.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/symbol.c b/symbol.c
index 4da253b..df760d4 100644
--- a/symbol.c
+++ b/symbol.c
@@ -861,7 +861,7 @@ static const struct ctype_declare {
{ &string_ctype, SYM_PTR, 0, &bits_in_pointer, &pointer_alignment, &char_ctype },
{ &ptr_ctype, SYM_PTR, 0, &bits_in_pointer, &pointer_alignment, &void_ctype },
- { &null_ctype, SYM_PTR, 0, &bits_in_pointer, &pointer_alignment, &void_ctype },
+ { &null_ctype, SYM_PTR, 0, &bits_in_pointer, &pointer_alignment, &ptr_ctype },
{ &label_ctype, SYM_PTR, 0, &bits_in_pointer, &pointer_alignment, &void_ctype },
{ &lazy_ptr_ctype, SYM_PTR, 0, &bits_in_pointer, &pointer_alignment, &void_ctype },
{ NULL, }
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