[PATCH] drm/xe: Fix build error for XE_IOCTL_DBG macro

[gyeyoung]

Thank you for your review, I missed how && work.
I will revise a patch that print only when cond is true.

sincerely,
Gyeyoung baek

On Tue, Oct 29, 2024 at 4:47 AM Lucas De Marchi
<lucas.demarchi at intel.com> wrote:
>
> On Sun, Oct 27, 2024 at 01:57:52PM +0900, Gyeyoung Baek wrote:
> >In the previous code, there is build error.
> >if CONFIG_DRM_USE_DYNAMIC_DEBUG is set,
> >'drm_dbg' function is replaced with '__dynamic_func_call_cls',
> >which is replaced with a do while statement.
> >
> >The problem is that,
> >XE_IOCTL_DBG uses this function for conditional expression.
> >
> >so I fix the expression to be compatible with the do while statement,
> >by referring to "https://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html".
> >
> >Signed-off-by: Gyeyoung Baek <gye976 at gmail.com>
> >---
> > drivers/gpu/drm/xe/xe_macros.h | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> >diff --git a/drivers/gpu/drm/xe/xe_macros.h b/drivers/gpu/drm/xe/xe_macros.h
> >index daf56c846d03..58a9d1e33502 100644
> >--- a/drivers/gpu/drm/xe/xe_macros.h
> >+++ b/drivers/gpu/drm/xe/xe_macros.h
> >@@ -11,8 +11,8 @@
> > #define XE_WARN_ON WARN_ON
> >
> > #define XE_IOCTL_DBG(xe, cond) \
> >-      ((cond) && (drm_dbg(&(xe)->drm, \
> >-                          "Ioctl argument check failed at %s:%d: %s", \
> >-                          __FILE__, __LINE__, #cond), 1))
> >+      ({drm_dbg(&(xe)->drm, \
> >+              "Ioctl argument check failed at %s:%d: %s", \
> >+              __FILE__, __LINE__, #cond); (cond); })
>
> but this would print the debug message regardless of the cond being
> true. Previously this would enter the condition if cond && 1 (due to the
> comma operator use), but printing the message was shortcut when cond was
> false.
>
> It looks like keeping cond outside and the statement expr to cover only
> the call to drm_dbg would work.
>
> Lucas De Marchi
>
> > #endif
> >--
> >2.34.1
> >