Re: [PATCH][next] iommufd/iommufd_private.h: Avoid -Wflex-array-member-not-at-end warning
From: Nicolin Chen
Date: Tue Nov 11 2025 - 13:58:51 EST
On Tue, Nov 11, 2025 at 05:49:20PM +0900, Gustavo A. R. Silva wrote:
> On 11/11/25 16:20, Gustavo A. R. Silva wrote:
> > On 11/11/25 03:02, Nicolin Chen wrote:
> > > On Mon, Nov 10, 2025 at 08:35:31PM +0900, Gustavo A. R. Silva wrote:
> > > > -Wflex-array-member-not-at-end was introduced in GCC-14, and we are
> > > > getting ready to enable it, globally.
> > > >
> > > > Move the conflicting declaration to the end of the corresponding
> > > > structure. Notice that struct iommufd_vevent is a flexible
> > > > structure, this is a structure that contains a flexible-array
> > > > member.
> > > >
> > > > Fix the following warning:
> > > >
> > > > drivers/iommu/iommufd/iommufd_private.h:621:31: warning:
> > > > structure containing a flexible array member is not at the end
> > > > of another structure [-Wflex-array- member-not-at-end]
> > >
> > > IIUIC, there might be data corruption due to this? If so, I think
>
> Okay, I didn't find evidence of data corruption. So, this patch can be applied to
> a -next tree.
Revisiting the design, the "lost_events_header" doesn't allocate
data but only uses its internal header to raise a flag. So there
should not be any data corruption.
Yea, I think we are fine with your for-next patch.
Thanks
Nicolin