Fix compiler warning "discards qualifiers from pointer target type", by allowing explicit discard of const qualifier thru type casting. The const_cast() macro is taken from a patch from Kaveh R. Ghazi [PATCH]: Fix problematic -Wcast-qual cases using new CONST_CAST macro posted on http://old.nabble.com/-PATCH-:-Fix-problematic--Wcast-qual-cases-using-new-CONST_CAST--macro-td11824676.html The proposed __nowarn__ keyword has not yet been implemented, (see http://gcc.gnu.org/ml/gcc-patches/2009-11/msg01261.html). Signed-off-by: Laurent Chavey <chavey@xxxxxxxxxx> --- include/linux/kernel.h | 12 ++++++++++++ net/ipv4/netfilter/ipt_ULOG.c | 2 +- net/netfilter/xt_time.c | 2 +- 3 files changed, 14 insertions(+), 2 deletions(-) diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 3fa4c59..0246771 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -710,4 +710,16 @@ struct sysinfo { # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD #endif +/* Cast away const-ness to pass -Wcast-qual */ +#ifdef __GNUC__ +union gcc_constcast +{ + const void *cv; + void *v; +}; +#define const_cast(X) ((__extension__(union gcc_constcast)(const void *)(X)).v) +#else +#define const_cast(X) ((void *)(X)) +#endif + #endif diff --git a/net/ipv4/netfilter/ipt_ULOG.c b/net/ipv4/netfilter/ipt_ULOG.c index d32cc4b..c8f8b8b 100644 --- a/net/ipv4/netfilter/ipt_ULOG.c +++ b/net/ipv4/netfilter/ipt_ULOG.c @@ -210,7 +210,7 @@ static void ipt_ulog_packet(unsigned int hooknum, /* We might not have a timestamp, get one */ if (skb->tstamp.tv64 == 0) - __net_timestamp((struct sk_buff *)skb); + __net_timestamp((struct sk_buff *)const_cast(skb)); /* copy hook, prefix, timestamp, payload, etc. */ pm->data_len = copy_len; diff --git a/net/netfilter/xt_time.c b/net/netfilter/xt_time.c index 93acaa5..8f34a4a 100644 --- a/net/netfilter/xt_time.c +++ b/net/netfilter/xt_time.c @@ -170,7 +170,7 @@ time_mt(const struct sk_buff *skb, const struct xt_match_param *par) * it arrived at the right moment before 13:00. */ if (skb->tstamp.tv64 == 0) - __net_timestamp((struct sk_buff *)skb); + __net_timestamp((struct sk_buff *)const_cast(skb)); stamp = ktime_to_ns(skb->tstamp); stamp = div_s64(stamp, NSEC_PER_SEC); -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
