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SubjectRe: [PATCH][next] ath: Replace zero-length array with flexible-array member
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Date
"Gustavo A. R. Silva" <gustavo@embeddedor.com> 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
> inadvertently introduced[3] to the codebase from now on.
>
> Also, notice that, dynamic memory allocations won't be affected by
> this change:
>
> "Flexible array members have incomplete type, and so the sizeof operator
> may not be applied. As a quirk of the original implementation of
> zero-length arrays, sizeof evaluates to zero."[1]
>
> This issue was detected 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@embeddedor.com>

Fails to apply, please rebase on top of my ath.git master branch.

error: patch failed: drivers/net/wireless/ath/ath10k/core.h:1223
error: drivers/net/wireless/ath/ath10k/core.h: patch does not apply
error: patch failed: drivers/net/wireless/ath/ath11k/debug.h:65
error: drivers/net/wireless/ath/ath11k/debug.h: patch does not apply
error: patch failed: drivers/net/wireless/ath/ath11k/rx_desc.h:1206
error: drivers/net/wireless/ath/ath11k/rx_desc.h: patch does not apply
stg import: Diff does not apply cleanly

Patch set to Changes Requested.

--
https://patchwork.kernel.org/patch/11401227/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches

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