| Message ID | 20181108144458.29012-24-maier@linux.ibm.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | zfcp updates for v4.21 | expand |
On 11/8/18 3:44 PM, Steffen Maier wrote: > This was introduced with v2.6.27 commit 287ac01acf22 ("[SCSI] zfcp: Cleanup > code in zfcp_erp.c") but would now suppress helpful -Wswitch compiler > warnings when building with W=1 such as the following forced example: > > drivers/s390/scsi/zfcp_erp.c: In function 'zfcp_erp_setup_act': > drivers/s390/scsi/zfcp_erp.c:220:2: warning: enumeration value 'ZFCP_ERP_ACTION_REOPEN_PORT' not handled in switch [-Wswitch] > switch (need) { > ^~~~~~ > > But then again, only with W=1 we would notice unhandled enum cases. > Without the default cases and a missed unhandled enum case, the code > might perform unforeseen things we might not want... > > As of today, we never run through the removed default case, > so removing it is no functional change. > In the future, we never should run through a default case but > introduce the necessary specific case(s) to handle new functionality. > > Signed-off-by: Steffen Maier <maier@linux.ibm.com> > Reviewed-by: Benjamin Block <bblock@linux.ibm.com> > --- > drivers/s390/scsi/zfcp_erp.c | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c > index 9345fed3bb37..744a64680d5b 100644 > --- a/drivers/s390/scsi/zfcp_erp.c > +++ b/drivers/s390/scsi/zfcp_erp.c > @@ -257,9 +257,6 @@ static struct zfcp_erp_action *zfcp_erp_setup_act(enum zfcp_erp_act_type need, > ZFCP_STATUS_COMMON_RUNNING)) > act_status |= ZFCP_STATUS_ERP_CLOSE_ONLY; > break; > - > - default: > - return NULL; > } > > WARN_ON_ONCE(erp_action->adapter != adapter); > Same here. If you don't expect the code to run into this case, please do add a WARN_ON() or something so that it can be tracked down. Cheers, Hannes
diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c index 9345fed3bb37..744a64680d5b 100644 --- a/drivers/s390/scsi/zfcp_erp.c +++ b/drivers/s390/scsi/zfcp_erp.c @@ -257,9 +257,6 @@ static struct zfcp_erp_action *zfcp_erp_setup_act(enum zfcp_erp_act_type need, ZFCP_STATUS_COMMON_RUNNING)) act_status |= ZFCP_STATUS_ERP_CLOSE_ONLY; break; - - default: - return NULL; } WARN_ON_ONCE(erp_action->adapter != adapter);
This was introduced with v2.6.27 commit 287ac01acf22 ("[SCSI] zfcp: Cleanup code in zfcp_erp.c") but would now suppress helpful -Wswitch compiler warnings when building with W=1 such as the following forced example: drivers/s390/scsi/zfcp_erp.c: In function 'zfcp_erp_setup_act': drivers/s390/scsi/zfcp_erp.c:220:2: warning: enumeration value 'ZFCP_ERP_ACTION_REOPEN_PORT' not handled in switch [-Wswitch] switch (need) { ^~~~~~ But then again, only with W=1 we would notice unhandled enum cases. Without the default cases and a missed unhandled enum case, the code might perform unforeseen things we might not want... As of today, we never run through the removed default case, so removing it is no functional change. In the future, we never should run through a default case but introduce the necessary specific case(s) to handle new functionality. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> --- drivers/s390/scsi/zfcp_erp.c | 3 --- 1 file changed, 3 deletions(-)