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[net-next,v2] ptp: ocp: Avoid operator precedence warning in ptp_ocp_summary_show()

Message ID 20210917045204.1385801-1-nathan@kernel.org (mailing list archive)
State Accepted
Delegated to: Netdev Maintainers
Headers show
Series [net-next,v2] ptp: ocp: Avoid operator precedence warning in ptp_ocp_summary_show() | expand

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Commit Message

Nathan Chancellor Sept. 17, 2021, 4:52 a.m. UTC 
Clang warns twice:

drivers/ptp/ptp_ocp.c:2065:16: error: operator '?:' has lower precedence
than '&'; '&' will be evaluated first
[-Werror,-Wbitwise-conditional-parentheses]
                           on & map ? " ON" : "OFF", src);
                           ~~~~~~~~ ^
drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '&'
expression to silence this warning
                           on & map ? " ON" : "OFF", src);
                                    ^
                           (       )
drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '?:'
expression to evaluate it first
                           on & map ? " ON" : "OFF", src);
                                    ^

on and map are both booleans so this should be a logical AND, which
clears up the operator precedence issue.

Fixes: a62a56d04e63 ("ptp: ocp: Enable 4th timestamper / PPS generator")
Link: https://github.com/ClangBuiltLinux/linux/issues/1457
Suggested-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
---

v1 -> v2: https://lore.kernel.org/r/20210916194351.3860836-1-nathan@kernel.org/

* Change fix from adding parentheses to moving from bitwise to logical
  AND. Thanks to Jonathan for catching that both operands were boolean,
  which I unfortunately missed.

 drivers/ptp/ptp_ocp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)


base-commit: 8dc84dcd7f74b50f81de3dbf6f6b5b146e3a8eea

Comments

Jonathan Lemon Sept. 17, 2021, 5:41 a.m. UTC | #1 
On Thu, Sep 16, 2021 at 09:52:05PM -0700, Nathan Chancellor wrote:
> Clang warns twice:
> 
> drivers/ptp/ptp_ocp.c:2065:16: error: operator '?:' has lower precedence
> than '&'; '&' will be evaluated first
> [-Werror,-Wbitwise-conditional-parentheses]
>                            on & map ? " ON" : "OFF", src);
>                            ~~~~~~~~ ^
> drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '&'
> expression to silence this warning
>                            on & map ? " ON" : "OFF", src);
>                                     ^
>                            (       )
> drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '?:'
> expression to evaluate it first
>                            on & map ? " ON" : "OFF", src);
>                                     ^
> 
> on and map are both booleans so this should be a logical AND, which
> clears up the operator precedence issue.
> 
> Fixes: a62a56d04e63 ("ptp: ocp: Enable 4th timestamper / PPS generator")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1457
> Suggested-by: Jonathan Lemon <jonathan.lemon@gmail.com>
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>

Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Jakub Kicinski Sept. 17, 2021, 5:32 p.m. UTC | #2 
On Thu, 16 Sep 2021 22:41:14 -0700 Jonathan Lemon wrote:
> On Thu, Sep 16, 2021 at 09:52:05PM -0700, Nathan Chancellor wrote:
> > Clang warns twice:
> > 
> > drivers/ptp/ptp_ocp.c:2065:16: error: operator '?:' has lower precedence
> > than '&'; '&' will be evaluated first
> > [-Werror,-Wbitwise-conditional-parentheses]
> >                            on & map ? " ON" : "OFF", src);
> >                            ~~~~~~~~ ^
> > drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '&'
> > expression to silence this warning
> >                            on & map ? " ON" : "OFF", src);
> >                                     ^
> >                            (       )
> > drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '?:'
> > expression to evaluate it first
> >                            on & map ? " ON" : "OFF", src);
> >                                     ^
> > 
> > on and map are both booleans so this should be a logical AND, which
> > clears up the operator precedence issue.
> > 
> > Fixes: a62a56d04e63 ("ptp: ocp: Enable 4th timestamper / PPS generator")
> > Link: https://github.com/ClangBuiltLinux/linux/issues/1457
> > Suggested-by: Jonathan Lemon <jonathan.lemon@gmail.com>
> > Signed-off-by: Nathan Chancellor <nathan@kernel.org>  
> 
> Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>

Applied, thanks!
diff mbox series

Patch

diff --git a/drivers/ptp/ptp_ocp.c b/drivers/ptp/ptp_ocp.c
index 844b1401cc5d..c26708f486cf 100644
--- a/drivers/ptp/ptp_ocp.c
+++ b/drivers/ptp/ptp_ocp.c
@@ -2062,11 +2062,11 @@  ptp_ocp_summary_show(struct seq_file *s, void *data)
 		on = ioread32(&ts_reg->enable);
 		map = !!(bp->pps_req_map & OCP_REQ_TIMESTAMP);
 		seq_printf(s, "%7s: %s, src: %s\n", "TS3",
-			   on & map ? " ON" : "OFF", src);
+			   on && map ? " ON" : "OFF", src);
 
 		map = !!(bp->pps_req_map & OCP_REQ_PPS);
 		seq_printf(s, "%7s: %s, src: %s\n", "PPS",
-			   on & map ? " ON" : "OFF", src);
+			   on && map ? " ON" : "OFF", src);
 	}
 
 	if (bp->irig_out) {