On Thu, Nov 17, 2022 at 06:50:55PM +0530, Deepak R Varma wrote: > On Thu, Nov 17, 2022 at 01:54:49PM +0100, Greg Kroah-Hartman wrote: > > On Thu, Nov 17, 2022 at 03:48:45PM +0530, Deepak R Varma wrote: > > > The code currently uses C90 standard extension based zero length arrays. > > > The zero length array member also happens to be the only member of the > > > structs. Such zero length array declarations are deprecated and the > > > new C99 standard extension of flexible array declarations are to be > > > used instead. > > > > > > The DECLARE_FLEX_ARRAY() helper allows for a flexible array member as > > > the only member in a structure. Refer to these links [1], [2] for > > > details. > > > > > > [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html > > > [2] https://lkml.kernel.org/r/YxKY6O2hmdwNh8r8@work > > > > > > Issue identified using Coccinelle. > > > > > > Signed-off-by: Deepak R Varma <drv@xxxxxxxxx> > > > --- > > > > > > Notes: > > > 1. Proposed change is compile tested only. > > > 2. Solution feedback from gustavoars@xxxxxxxxxx > > > > > > > > > drivers/staging/wlan-ng/hfa384x.h | 6 +++--- > > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/staging/wlan-ng/hfa384x.h b/drivers/staging/wlan-ng/hfa384x.h > > > index 0611e37df6ac..3a1edcb43e07 100644 > > > --- a/drivers/staging/wlan-ng/hfa384x.h > > > +++ b/drivers/staging/wlan-ng/hfa384x.h > > > @@ -960,15 +960,15 @@ struct hfa384x_pdr_nicid { > > > } __packed; > > > > > > struct hfa384x_pdr_refdac_measurements { > > > - u16 value[0]; > > > + DECLARE_FLEX_ARRAY(u16, value); > > > } __packed; > > > > Why? This structure is never used anywhere, right? So why is this > > needed to be changed and not just removed entirely? Same for the other > > structures in this patch. > > Hello Greg, > I am unable to confirm that these structures are truly not needed in the absence > if a real device based testing. I could only validate that using the compile > build and driver loading. Think this through, if no one is actually using this structure, and it is of 0 size, then do you think it is being used? > This change that I am proposing in the interim would enable the compiler to > protect the structure from addition of a new member below the zero length array. Why would you want to add a new member below this? That's not what is happening here at all. Please think this through a bit more. good luck! greg k-h
