[PATCH v2] include/linux/byteorder/generic.h: fix signed/unsigned warnings

[PATCH v2] include/linux/byteorder/generic.h: fix signed/unsigned warnings

[Anatol Belski]

From: Anatol Belski <anbelski@microsoft.com>

This fixes the warnings like below, thrown by GCC

warning: comparison of integer expressions of different signedness: \
‘int’ and ‘size_t’ {aka ‘long unsigned int’} [-Wsign-compare]
  195 |  for (i = 0; i < len; i++)
      |                ^

Signed-off-by: Anatol Belski <anbelski@microsoft.com>
---
 include/linux/byteorder/generic.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/byteorder/generic.h b/include/linux/byteorder/generic.h
index 4b13e0a3e15b..c9a4c96c9943 100644
--- a/include/linux/byteorder/generic.h
+++ b/include/linux/byteorder/generic.h
@@ -190,7 +190,7 @@ static inline void be64_add_cpu(__be64 *var, u64 val)
 
 static inline void cpu_to_be32_array(__be32 *dst, const u32 *src, size_t len)
 {
-	int i;
+	size_t i;
 
 	for (i = 0; i < len; i++)
 		dst[i] = cpu_to_be32(src[i]);
@@ -198,7 +198,7 @@ static inline void cpu_to_be32_array(__be32 *dst, const u32 *src, size_t len)
 
 static inline void be32_to_cpu_array(u32 *dst, const __be32 *src, size_t len)
 {
-	int i;
+	size_t i;
 
 	for (i = 0; i < len; i++)
 		dst[i] = be32_to_cpu(src[i]);
-- 
2.20.1

Re: [PATCH v2] include/linux/byteorder/generic.h: fix signed/unsigned warnings

[Andy Shevchenko]

On Mon, Oct 21, 2019 at 09:27:37AM +0000, Anatol Belski wrote:
> From: Anatol Belski <anbelski@microsoft.com>
> 
> This fixes the warnings like below, thrown by GCC
> 
> warning: comparison of integer expressions of different signedness: \
> ‘int’ and ‘size_t’ {aka ‘long unsigned int’} [-Wsign-compare]
>   195 |  for (i = 0; i < len; i++)
>       |                ^

We have explicitly disabled this warnings in the kernel Makefile.
How did you achieve this? (yes, I know the possible answer, perhaps
this has to be mentioned as well)

Now I see some inconsistency with this warning between GCC and Clang. Add
related people to the discussion.

> Signed-off-by: Anatol Belski <anbelski@microsoft.com>
> ---

Changelog is missing.
(No need to resend just for this, it's for your future contributions)

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2] include/linux/byteorder/generic.h: fix signed/unsigned warnings

[Anatol Belski]

On Mon, 2019-10-21 at 12:38 +0300, Andy Shevchenko wrote:
> We have explicitly disabled this warnings in the kernel Makefile.
> How did you achieve this? (yes, I know the possible answer, perhaps
> this has to be mentioned as well)
Added W=12 to the make command, used GCC 9.1.0. There are quite some
warnings of this art yet, so this is just a first shot.

Additional issue i'd see in this particular case also, that iterating
through an array should use some unsigned to ensure there's no signed
overflow. But otherwise, it's better to fix similar cases to reduce the
noise.

> > Signed-off-by: Anatol Belski <anbelski@microsoft.com>
> > ---
> 
> Changelog is missing.
> (No need to resend just for this, it's for your future contributions)
> 
Thanks for pointing to this. I also probably should have added a Cc:.
Will go through the submitting patches document more carefully.

Thanks!

anatol