[PATCH] byteorder: fix warning due to type mismatch in be32 array code

[PATCH] byteorder: fix warning due to type mismatch in be32 array code

[Ben Dooks (Codethink)]

The loop should use a "size_t" as the len parameter is a size_t which
should silence the following warning:

./include/linux/byteorder/generic.h:195:16: warning: comparison of integer expressions of different signedness: ‘int’ and ‘size_t’ {aka ‘unsigned int’} [-Wsign-compare]
./include/linux/byteorder/generic.h:203:16: warning: comparison of integer expressions of different signedness: ‘int’ and ‘size_t’ {aka ‘unsigned int’} [-Wsign-compare]

Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
---
Cc: linux-kernel@vger.kernel.org
---
 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]);
-- 
2.23.0

Re: [PATCH] byteorder: fix warning due to type mismatch in be32 array code

[Geert Uytterhoeven]

Hi Ben,

CC Arnd.

On Mon, Nov 4, 2019 at 7:25 PM Ben Dooks (Codethink)
<ben.dooks@codethink.co.uk> wrote:
> The loop should use a "size_t" as the len parameter is a size_t which
> should silence the following warning:
>
> ./include/linux/byteorder/generic.h:195:16: warning: comparison of integer expressions of different signedness: ‘int’ and ‘size_t’ {aka ‘unsigned int’} [-Wsign-compare]
> ./include/linux/byteorder/generic.h:203:16: warning: comparison of integer expressions of different signedness: ‘int’ and ‘size_t’ {aka ‘unsigned int’} [-Wsign-compare]
>
> Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>

Thanks for your patch!

> --- 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]);

Alternatively, you can follow the approach a few lines above:

        while (len--)
                *dst++ = cpu_to_be32(*src++);

Regardless:
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds