gcc cannot prove that the value of sdata->vif.type does not change between the switch() statement and the second comparison to NL80211_IFTYPE_AP, causing a harmless warning. Slightly reordering the code makes the warning go away with no functional change. Without this patch, building ARM at91sam9g45_defconfig with gcc-4.6 results in: net/mac80211/tx.c: In function 'ieee80211_subif_start_xmit': net/mac80211/tx.c:1797:22: warning: 'chanctx_conf' may be used uninitialized in this function [-Wuninitialized] Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx> Cc: "John W. Linville" <linville@xxxxxxxxxxxxx> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: linux-wireless@xxxxxxxxxxxxxxx Cc: netdev@xxxxxxxxxxxxxxx --- net/mac80211/tx.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index e9eadc4..df589bf 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1784,16 +1784,16 @@ netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb, break; /* fall through */ case NL80211_IFTYPE_AP: + if (sdata->vif.type == NL80211_IFTYPE_AP) + chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); + if (!chanctx_conf) + goto fail_rcu; fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS); /* DA BSSID SA */ memcpy(hdr.addr1, skb->data, ETH_ALEN); memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN); memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN); hdrlen = 24; - if (sdata->vif.type == NL80211_IFTYPE_AP) - chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); - if (!chanctx_conf) - goto fail_rcu; band = chanctx_conf->def.chan->band; break; case NL80211_IFTYPE_WDS: -- 1.8.0 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html