* [PATCH] iwlwifi: work around clang -Wuninitialized warning
@ 2019-03-22 14:13 Arnd Bergmann
2019-03-23 6:11 ` Luca Coelho
0 siblings, 1 reply; 3+ messages in thread
From: Arnd Bergmann @ 2019-03-22 14:13 UTC (permalink / raw)
To: Johannes Berg
Cc: clang-built-linux, Nick Desaulniers, Nathan Chancellor,
Arnd Bergmann, Emmanuel Grumbach, Luca Coelho,
Intel Linux Wireless, Kalle Valo, David S. Miller, Sara Sharon,
Avraham Stern, linux-wireless, netdev, linux-kernel
Clang incorrectly warns about an uninitialized variable:
drivers/net/wireless/intel/iwlwifi/mvm/sta.c:2114:12: error: variable 'queue' is used uninitialized whenever 'if'
condition is false [-Werror,-Wsometimes-uninitialized]
else if (WARN(1, "Missing required TXQ for adding bcast STA\n"))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/asm-generic/bug.h:130:36: note: expanded from macro 'WARN'
#define WARN(condition, format...) ({ \
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/wireless/intel/iwlwifi/mvm/sta.c:2119:33: note: uninitialized use occurs here
iwl_mvm_enable_txq(mvm, NULL, queue, 0, &cfg, wdg_timeout);
^~~~~
drivers/net/wireless/intel/iwlwifi/mvm/sta.c:2114:8: note: remove the 'if' if its condition is always true
else if (WARN(1, "Missing required TXQ for adding bcast STA\n"))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/wireless/intel/iwlwifi/mvm/sta.c:2094:11: note: initialize the variable 'queue' to silence this warning
int queue;
^
= 0
1 error generated.
This cannot happen because the if/else if/else if block always
has one code path that is entered. However, we can simply
rearrange the code to let clang see this as well.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/net/wireless/intel/iwlwifi/mvm/sta.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index 498c315291cf..91ce56d2ebb8 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -2107,12 +2107,14 @@ int iwl_mvm_send_add_bcast_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif)
if (!iwl_mvm_has_new_tx_api(mvm)) {
if (vif->type == NL80211_IFTYPE_AP ||
- vif->type == NL80211_IFTYPE_ADHOC)
+ vif->type == NL80211_IFTYPE_ADHOC) {
queue = mvm->probe_queue;
- else if (vif->type == NL80211_IFTYPE_P2P_DEVICE)
+ } else if (vif->type == NL80211_IFTYPE_P2P_DEVICE) {
queue = mvm->p2p_dev_queue;
- else if (WARN(1, "Missing required TXQ for adding bcast STA\n"))
+ } else {
+ WARN(1, "Missing required TXQ for adding bcast STA\n");
return -EINVAL;
+ }
bsta->tfd_queue_msk |= BIT(queue);
--
2.20.0
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] iwlwifi: work around clang -Wuninitialized warning
2019-03-22 14:13 [PATCH] iwlwifi: work around clang -Wuninitialized warning Arnd Bergmann
@ 2019-03-23 6:11 ` Luca Coelho
2019-03-23 11:28 ` Arnd Bergmann
0 siblings, 1 reply; 3+ messages in thread
From: Luca Coelho @ 2019-03-23 6:11 UTC (permalink / raw)
To: Arnd Bergmann, Johannes Berg
Cc: clang-built-linux, Nick Desaulniers, Nathan Chancellor,
Emmanuel Grumbach, Intel Linux Wireless, Kalle Valo,
David S. Miller, Sara Sharon, Avraham Stern, linux-wireless,
netdev, linux-kernel
On Fri, 2019-03-22 at 15:13 +0100, Arnd Bergmann wrote:
> Clang incorrectly warns about an uninitialized variable:
>
> drivers/net/wireless/intel/iwlwifi/mvm/sta.c:2114:12: error: variable
> 'queue' is used uninitialized whenever 'if'
> condition is false [-Werror,-Wsometimes-uninitialized]
> else if (WARN(1, "Missing required TXQ for adding
> bcast STA\n"))
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ~~~~~~~~~~
> include/asm-generic/bug.h:130:36: note: expanded from macro 'WARN'
> #define WARN(condition, format...)
> ({ \
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ~~~~
> drivers/net/wireless/intel/iwlwifi/mvm/sta.c:2119:33: note:
> uninitialized use occurs here
> iwl_mvm_enable_txq(mvm, NULL, queue, 0, &cfg,
> wdg_timeout);
> ^~~~~
> drivers/net/wireless/intel/iwlwifi/mvm/sta.c:2114:8: note: remove the
> 'if' if its condition is always true
> else if (WARN(1, "Missing required TXQ for adding
> bcast STA\n"))
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ~~~~~~~~~~~
> drivers/net/wireless/intel/iwlwifi/mvm/sta.c:2094:11: note:
> initialize the variable 'queue' to silence this warning
> int queue;
> ^
> = 0
> 1 error generated.
>
> This cannot happen because the if/else if/else if block always
> has one code path that is entered. However, we can simply
> rearrange the code to let clang see this as well.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
Thanks for the patch, Arnd! But I have already queued up an equivalent
patch for v5.2 (should probably reach linux-next by the end of next
week or so):
https://patchwork.kernel.org/patch/10844025/
--
Cheers,
Luca.
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] iwlwifi: work around clang -Wuninitialized warning
2019-03-23 6:11 ` Luca Coelho
@ 2019-03-23 11:28 ` Arnd Bergmann
0 siblings, 0 replies; 3+ messages in thread
From: Arnd Bergmann @ 2019-03-23 11:28 UTC (permalink / raw)
To: Luca Coelho
Cc: Johannes Berg, clang-built-linux, Nick Desaulniers,
Nathan Chancellor, Emmanuel Grumbach, Intel Linux Wireless,
Kalle Valo, David S. Miller, Sara Sharon, Avraham Stern,
linux-wireless, Networking, Linux Kernel Mailing List
On Sat, Mar 23, 2019 at 7:11 AM Luca Coelho <luca@coelho.fi> wrote:
>
> On Fri, 2019-03-22 at 15:13 +0100, Arnd Bergmann wrote:
> > Clang incorrectly warns about an uninitialized variable:
> >
> >
> > This cannot happen because the if/else if/else if block always
> > has one code path that is entered. However, we can simply
> > rearrange the code to let clang see this as well.
> >
> > Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> > ---
>
> Thanks for the patch, Arnd! But I have already queued up an equivalent
> patch for v5.2 (should probably reach linux-next by the end of next
> week or so):
>
> https://patchwork.kernel.org/patch/10844025/
Thanks, and sorry for the duplicate. I forgot to check for the
patches that Nathan had already done when I started sending
out my own series on the same issues.
Arnd
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2019-03-23 11:28 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-03-22 14:13 [PATCH] iwlwifi: work around clang -Wuninitialized warning Arnd Bergmann
2019-03-23 6:11 ` Luca Coelho
2019-03-23 11:28 ` Arnd Bergmann
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).