On Fri, 19 May 2023 22:54:46 +0200,
Gustavo A. R. Silva wrote:
>
> One-element arrays are deprecated, and we are replacing them with flexible
> array members instead. However, in this case it seems those one-element
> arrays have never actually been used as fake flexible arrays.
>
> See this code that dates from Linux-2.6.12-rc2 initial git repository build
> (commit 1da177e4c3f4 ("Linux-2.6.12-rc2")):
>
> sound/pci/mixart/mixart_core.h:
> 215 struct mixart_stream_state_req
> 216 {
> 217 u32 delayed;
> 218 u64 scheduler;
> 219 u32 reserved4np[3];
> 220 u32 stream_count; /* set to 1 for instance */
> 221 struct mixart_flow_info stream_info; /* could be an array[stream_count] */
> 222 } __attribute__((packed));
>
> sound/pci/mixart/mixart.c:
> 388
> 389 memset(&stream_state_req, 0, sizeof(stream_state_req));
> 390 stream_state_req.stream_count = 1;
> 391 stream_state_req.stream_info.stream_desc.uid_pipe = stream->pipe->group_uid;
> 392 stream_state_req.stream_info.stream_desc.stream_idx = stream->substream->number;
> 393
>
> So, taking the code above as example, replace multiple one-element
> arrays with simple object declarations, and refactor the rest of the
> code, accordingly.
>
> This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
> routines on memcpy() and help us make progress towards globally
> enabling -fstrict-flex-arrays=3 [1].
>
> This results in no differences in binary output.
>
> Link: https://github.com/KSPP/linux/issues/79
> Link: https://github.com/KSPP/linux/issues/296
> Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
> Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
Thanks, applied.
Takashi
