"Gustavo A. R. Silva" <gustavo@xxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxx> 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