Re: [lwip-devel] [PATCH] ip_addr.h: Add cast in IP_SET_TYPE() macro in order to fix compiler warnings/errors

[address@hidden]

Am 01.01.2019 um 19:38 schrieb Jacob Kroon:
> Fix building unit tests (contrib/ports/unix/check) on Debian 9, gcc 6.3.0.
>
> Fixes:
> <snip>/ip_addr.h:105:58: error: the comparison will always evaluate as ‘true’ 
> for the address of ‘ip1’ will never be NULL [-Werror=address]
>   #define IP_SET_TYPE(ipaddr, iptype)     do { if((ipaddr) != NULL) { 
> IP_SET_TYPE_VAL(*(ipaddr),iptype); }}while(0)
>
> Signed-off-by: Jacob Kroon <address@hidden>

In contrast to other open source projects, we don't use this mailing 
list to send raw patches. We use the bugtracker at savannah instead.

> ---
>   src/include/lwip/ip_addr.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/src/include/lwip/ip_addr.h b/src/include/lwip/ip_addr.h
> index ee7a0c9d..aed7fbcf 100644
> --- a/src/include/lwip/ip_addr.h
> +++ b/src/include/lwip/ip_addr.h
> @@ -102,7 +102,7 @@ extern const ip_addr_t ip_addr_any_type;
>   #define IP_IS_V6(ipaddr)              (((ipaddr) != NULL) && 
> IP_IS_V6_VAL(*(ipaddr)))
>   
>   #define IP_SET_TYPE_VAL(ipaddr, iptype) do { (ipaddr).type = (iptype); }while(0)
> -#define IP_SET_TYPE(ipaddr, iptype)     do { if((ipaddr) != NULL) { 
> IP_SET_TYPE_VAL(*(ipaddr), iptype); }}while(0)
> +#define IP_SET_TYPE(ipaddr, iptype)     do { if((void*)(ipaddr) != NULL) { 
> IP_SET_TYPE_VAL(*(ipaddr), iptype); }}while(0)

This change silences all those warnings. Instead, we want to use 
IP_SET_TYPE_VAL() for the callers where this warning appears.

Regards,
Simon

>   #define IP_GET_TYPE(ipaddr)           ((ipaddr)->type)
>   
>   #define IP_ADDR_RAW_SIZE(ipaddr)      (IP_GET_TYPE(&ipaddr) == IPADDR_TYPE_V4 ? sizeof(ip4_addr_t) : sizeof(ip6_addr_t))