| Message ID | 1359504662-23561-1-git-send-email-swarren@wwwdotorg.org (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Tue, 2013-01-29 at 17:11 -0700, Stephen Warren wrote: > From: Stephen Warren <swarren@nvidia.com> > > Silence the following: > net/wireless/nl80211.c: In function '__cfg80211_wdev_from_attrs.clone.119': > net/wireless/nl80211.c:57:6: warning: 'wdev_id' may be used uninitialized in this function > > ... by always initializing wdev_id to zero. I assume that wiphy_idx and > ifidx are set to -1 for similar reasons, so this change simply propagates > the same workaround. > > In practice, this warning is false, since wdev_id is both set and used > under the condition if (have_wdev_id). However, at least my compiler > can't be coerced into realizing this; almost any code between the if > blocks that set and use the variable causes this warning. I don't see this warning? What compiler are you using? johannes -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 01/30/2013 12:57 AM, Johannes Berg wrote: > On Tue, 2013-01-29 at 17:11 -0700, Stephen Warren wrote: >> From: Stephen Warren <swarren@nvidia.com> >> >> Silence the following: >> net/wireless/nl80211.c: In function '__cfg80211_wdev_from_attrs.clone.119': >> net/wireless/nl80211.c:57:6: warning: 'wdev_id' may be used uninitialized in this function >> >> ... by always initializing wdev_id to zero. I assume that wiphy_idx and >> ifidx are set to -1 for similar reasons, so this change simply propagates >> the same workaround. >> >> In practice, this warning is false, since wdev_id is both set and used >> under the condition if (have_wdev_id). However, at least my compiler >> can't be coerced into realizing this; almost any code between the if >> blocks that set and use the variable causes this warning. > > I don't see this warning? What compiler are you using? I'm using gcc-4.5.3 for ARM. I checked with gcc-4.6.3 and gcc-4.7.2 and indeed I don't see the warning there. -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, 2013-01-30 at 09:49 -0700, Stephen Warren wrote: > On 01/30/2013 12:57 AM, Johannes Berg wrote: > > On Tue, 2013-01-29 at 17:11 -0700, Stephen Warren wrote: > >> From: Stephen Warren <swarren@nvidia.com> > >> > >> Silence the following: > >> net/wireless/nl80211.c: In function '__cfg80211_wdev_from_attrs.clone.119': > >> net/wireless/nl80211.c:57:6: warning: 'wdev_id' may be used uninitialized in this function > >> > >> ... by always initializing wdev_id to zero. I assume that wiphy_idx and > >> ifidx are set to -1 for similar reasons, so this change simply propagates > >> the same workaround. > >> > >> In practice, this warning is false, since wdev_id is both set and used > >> under the condition if (have_wdev_id). However, at least my compiler > >> can't be coerced into realizing this; almost any code between the if > >> blocks that set and use the variable causes this warning. > > > > I don't see this warning? What compiler are you using? > > I'm using gcc-4.5.3 for ARM. I checked with gcc-4.6.3 and gcc-4.7.2 and > indeed I don't see the warning there. Interesting. So should I keep it or remove it? I guess in this particular instance it doesn't matter all that much. In other cases I'd be more against changing it I guess. johannes -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 01/31/2013 01:51 PM, Johannes Berg wrote: > On Wed, 2013-01-30 at 09:49 -0700, Stephen Warren wrote: >> On 01/30/2013 12:57 AM, Johannes Berg wrote: >>> On Tue, 2013-01-29 at 17:11 -0700, Stephen Warren wrote: >>>> From: Stephen Warren <swarren@nvidia.com> >>>> >>>> Silence the following: >>>> net/wireless/nl80211.c: In function '__cfg80211_wdev_from_attrs.clone.119': >>>> net/wireless/nl80211.c:57:6: warning: 'wdev_id' may be used uninitialized in this function >>>> >>>> ... by always initializing wdev_id to zero. I assume that wiphy_idx and >>>> ifidx are set to -1 for similar reasons, so this change simply propagates >>>> the same workaround. >>>> >>>> In practice, this warning is false, since wdev_id is both set and used >>>> under the condition if (have_wdev_id). However, at least my compiler >>>> can't be coerced into realizing this; almost any code between the if >>>> blocks that set and use the variable causes this warning. >>> >>> I don't see this warning? What compiler are you using? >> >> I'm using gcc-4.5.3 for ARM. I checked with gcc-4.6.3 and gcc-4.7.2 and >> indeed I don't see the warning there. > > Interesting. So should I keep it or remove it? I guess in this > particular instance it doesn't matter all that much. In other cases I'd > be more against changing it I guess. It's your call. I guess since it's fixed going forward in gcc, you may as well drop it though. -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 33de803..389e62a 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -54,7 +54,7 @@ __cfg80211_wdev_from_attrs(struct net *netns, struct nlattr **attrs) struct wireless_dev *result = NULL; bool have_ifidx = attrs[NL80211_ATTR_IFINDEX]; bool have_wdev_id = attrs[NL80211_ATTR_WDEV]; - u64 wdev_id; + u64 wdev_id = 0; int wiphy_idx = -1; int ifidx = -1;