Re: [PATCH] firmware: arm_scmi: driver: Replace zero-length array with flexible-array member

From: Sudeep Holla
Date: Thu Feb 20 2020 - 12:18:44 EST


On Tue, Feb 11, 2020 at 05:10:45PM -0600, Gustavo A. R. Silva wrote:
> The current codebase makes use of the zero-length array language
> extension to the C90 standard, but the preferred mechanism to declare
> variable-length types such as these ones is a flexible array member[1][2],
> introduced in C99:
>
> struct foo {
> int stuff;
> struct boo array[];
> };
>
> By making use of the mechanism above, we will get a compiler warning
> in case the flexible array does not occur last in the structure, which
> will help us prevent some kind of undefined behavior bugs from being
> inadvertenly introduced[3] to the codebase from now on.
>
> This issue was found with the help of Coccinelle.
>
> [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
> [2] https://github.com/KSPP/linux/issues/21
> [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
>
> Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>

Applied these 3 patches [0][1][2] for v5.7

--
Regards,
Sudeep

[0]: https://lore.kernel.org/r/20200211231604.GA17274@embeddedor
[1]: https://lore.kernel.org/r/20200211231252.GA14830@embeddedor
[2]: https://lore.kernel.org/r/20200211231045.GA13956@embeddedor