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Subject: Re: [PATCH] gpu: drm: use struct_size() in kmalloc()
Message-ID: <5a9089f3-501b-24a1-202b-5a2b2ae62de6@embeddedor.com>
Date:   Tue, 21 May 2019 07:57:36 -0500
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On 5/21/19 3:59 AM, Christian König wrote:

> BTW: Is there actually good documentation how to correctly do the variable length array at end of structure thing in the kernel?
> 
> I do know that I've seen a lot of different variants like array[] array[0] or array[1] and I have also seen a bunch of gcc versions failing to generate correct
> code for some of them.
> 
> So we should probably nail down how to do things correctly.
> 

A flexible array member is the preferred[1] mechanism:

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?h=next-20190520&id=76497732932f15e7323dc805e8ea8dc11bb587cf

Thanks
--
Gustavo

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html