| Message ID | 20180926045435.9213-1-natechancellor@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | scsi: bfa: Avoid implicit enum conversion in bfad_im_post_vendor_event | expand |
On Tue, Sep 25, 2018 at 9:58 PM Nathan Chancellor <natechancellor@gmail.com> wrote: > > Clang warns when one enumerated type is implicitly converted to another. > > drivers/scsi/bfa/bfa_fcs_lport.c:379:26: warning: implicit conversion > from enumeration type 'enum bfa_lport_aen_event' to different > enumeration type 'enum bfa_ioc_aen_event' [-Wenum-conversion] > BFA_AEN_CAT_LPORT, event); > ^~~~~ > > The root cause of these warnings is the bfad_im_post_vendor_event > function, which expects a value from enum bfa_ioc_aen_event but there > are multiple instances of values from enums bfa_port_aen_event, > bfa_audit_aen_event, and bfa_lport_aen_event being used in this > function. Indeed, it seems that bfad_im_post_vendor_event() assigns this parameter to 161 entry->aen_type = evt; which is defined as: 1456 u32 aen_type; so already we know that aen_type is meant to be a grab bag of enum values. bfad_im_post_vendor_event() is already passed many different types of enums, as you mention. Does changing aen_type to an `int` produce further warnings, because it would be nice to have that change in this one, too. AFAICT, it's only ever saved away in a containing struct. > > Given that this doesn't appear to be a problem since cat helps with > differentiating the events, just change evt's type to int so that no > conversion needs to happen and Clang won't warn. > > Link: https://github.com/ClangBuiltLinux/linux/issues/147 > Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> > --- > > The alternate way of fixing these warnings is to explicitly cast the > conversion when calling the function but since there are about 8-10 of > these warnings, it seems logical to just change the function definiton > which is cleaner in my opinion. > > See commits 3eb95feac113 ("mm/zsmalloc.c: change stat type parameter to > int") and 04fecbf51b3c ("mm: memcontrol: use int for event/state > parameter in several functions") for similar fixes. > > drivers/scsi/bfa/bfad_im.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/scsi/bfa/bfad_im.h b/drivers/scsi/bfa/bfad_im.h > index e61ed8dad0b4..bd4ac187fd8e 100644 > --- a/drivers/scsi/bfa/bfad_im.h > +++ b/drivers/scsi/bfa/bfad_im.h > @@ -143,7 +143,7 @@ struct bfad_im_s { > static inline void bfad_im_post_vendor_event(struct bfa_aen_entry_s *entry, > struct bfad_s *drv, int cnt, > enum bfa_aen_category cat, > - enum bfa_ioc_aen_event evt) > + int evt) > { > struct timespec64 ts; > > -- > 2.19.0 >
On Thu, Sep 27, 2018 at 04:35:37PM -0700, Nick Desaulniers wrote: > On Tue, Sep 25, 2018 at 9:58 PM Nathan Chancellor > <natechancellor@gmail.com> wrote: > > > > Clang warns when one enumerated type is implicitly converted to another. > > > > drivers/scsi/bfa/bfa_fcs_lport.c:379:26: warning: implicit conversion > > from enumeration type 'enum bfa_lport_aen_event' to different > > enumeration type 'enum bfa_ioc_aen_event' [-Wenum-conversion] > > BFA_AEN_CAT_LPORT, event); > > ^~~~~ > > > > The root cause of these warnings is the bfad_im_post_vendor_event > > function, which expects a value from enum bfa_ioc_aen_event but there > > are multiple instances of values from enums bfa_port_aen_event, > > bfa_audit_aen_event, and bfa_lport_aen_event being used in this > > function. > > Indeed, it seems that bfad_im_post_vendor_event() assigns this parameter to > 161 entry->aen_type = evt; > > which is defined as: > > 1456 u32 aen_type; > > so already we know that aen_type is meant to be a grab bag of enum > values. bfad_im_post_vendor_event() is already passed many different > types of enums, as you mention. Does changing aen_type to an `int` > produce further warnings, because it would be nice to have that change > in this one, too. AFAICT, it's only ever saved away in a containing > struct. > No, it doesn't introduce any new warnings. I can send that as a v2 here shortly. Nathan > > > > Given that this doesn't appear to be a problem since cat helps with > > differentiating the events, just change evt's type to int so that no > > conversion needs to happen and Clang won't warn. > > > > Link: https://github.com/ClangBuiltLinux/linux/issues/147 > > Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> > > --- > > > > The alternate way of fixing these warnings is to explicitly cast the > > conversion when calling the function but since there are about 8-10 of > > these warnings, it seems logical to just change the function definiton > > which is cleaner in my opinion. > > > > See commits 3eb95feac113 ("mm/zsmalloc.c: change stat type parameter to > > int") and 04fecbf51b3c ("mm: memcontrol: use int for event/state > > parameter in several functions") for similar fixes. > > > > drivers/scsi/bfa/bfad_im.h | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/scsi/bfa/bfad_im.h b/drivers/scsi/bfa/bfad_im.h > > index e61ed8dad0b4..bd4ac187fd8e 100644 > > --- a/drivers/scsi/bfa/bfad_im.h > > +++ b/drivers/scsi/bfa/bfad_im.h > > @@ -143,7 +143,7 @@ struct bfad_im_s { > > static inline void bfad_im_post_vendor_event(struct bfa_aen_entry_s *entry, > > struct bfad_s *drv, int cnt, > > enum bfa_aen_category cat, > > - enum bfa_ioc_aen_event evt) > > + int evt) > > { > > struct timespec64 ts; > > > > -- > > 2.19.0 > > > > > -- > Thanks, > ~Nick Desaulniers
diff --git a/drivers/scsi/bfa/bfad_im.h b/drivers/scsi/bfa/bfad_im.h index e61ed8dad0b4..bd4ac187fd8e 100644 --- a/drivers/scsi/bfa/bfad_im.h +++ b/drivers/scsi/bfa/bfad_im.h @@ -143,7 +143,7 @@ struct bfad_im_s { static inline void bfad_im_post_vendor_event(struct bfa_aen_entry_s *entry, struct bfad_s *drv, int cnt, enum bfa_aen_category cat, - enum bfa_ioc_aen_event evt) + int evt) { struct timespec64 ts;
Clang warns when one enumerated type is implicitly converted to another. drivers/scsi/bfa/bfa_fcs_lport.c:379:26: warning: implicit conversion from enumeration type 'enum bfa_lport_aen_event' to different enumeration type 'enum bfa_ioc_aen_event' [-Wenum-conversion] BFA_AEN_CAT_LPORT, event); ^~~~~ The root cause of these warnings is the bfad_im_post_vendor_event function, which expects a value from enum bfa_ioc_aen_event but there are multiple instances of values from enums bfa_port_aen_event, bfa_audit_aen_event, and bfa_lport_aen_event being used in this function. Given that this doesn't appear to be a problem since cat helps with differentiating the events, just change evt's type to int so that no conversion needs to happen and Clang won't warn. Link: https://github.com/ClangBuiltLinux/linux/issues/147 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> --- The alternate way of fixing these warnings is to explicitly cast the conversion when calling the function but since there are about 8-10 of these warnings, it seems logical to just change the function definiton which is cleaner in my opinion. See commits 3eb95feac113 ("mm/zsmalloc.c: change stat type parameter to int") and 04fecbf51b3c ("mm: memcontrol: use int for event/state parameter in several functions") for similar fixes. drivers/scsi/bfa/bfad_im.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)