[SLOF] [PATCH] lib/libnet/ipv6: Silence compiler warning from Clang

[Alexey Kardashevskiy]

On 6/27/22 18:26, Thomas Huth wrote:
> When compiling the libnet code with Clang (e.g. for the s390-ccw bios),
> it complains with the following warning:
> 
>   ipv6.c:447:18: warning: variable length array folded to constant array
>    as an extension [-Wgnu-folding-constant]
>                  unsigned short raw[ip6size];
>                                 ^
> The warning is completely harmless, of course. Anyway let's rewrite the
> code a little bit to make the compiler silent again.
> 
> Signed-off-by: Thomas Huth <thuth at redhat.com>
> ---
>   lib/libnet/ipv6.c | 5 ++---
>   1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/lib/libnet/ipv6.c b/lib/libnet/ipv6.c
> index 6420004..259087b 100644
> --- a/lib/libnet/ipv6.c
> +++ b/lib/libnet/ipv6.c
> @@ -441,10 +441,9 @@ static unsigned short ip6_checksum(struct ip6hdr *ip6h, unsigned char *packet,
>   {
>   	int i;
>   	unsigned long checksum;
> -	const int ip6size = sizeof(struct ip6hdr)/sizeof(unsigned short);
>   	union {
>   		struct ip6hdr ip6h;
> -		unsigned short raw[ip6size];
> +		uint16_t raw[sizeof(struct ip6hdr) / sizeof(uint16_t)];
>   	} pseudo;
>   
>   	memcpy (&pseudo.ip6h, ip6h, sizeof(struct ip6hdr));
> @@ -455,7 +454,7 @@ static unsigned short ip6_checksum(struct ip6hdr *ip6h, unsigned char *packet,
>   	for (checksum = 0, i = 0; i < bytes; i += 2)
>   		checksum += (packet[i] << 8) | packet[i + 1];
>   
> -	for (i = 0; i < ip6size; i++)
> +	for (i = 0; i < (int)(sizeof(pseudo.raw) / sizeof(pseudo.raw[0])); i++)


ARRAY_SIZE()?


>   		checksum += pseudo.raw[i];
>   
>   	checksum = (checksum >> 16) + (checksum & 0xffff);

-- 
Alexey