On Fri, Jan 13, 2023 at 05:03:48PM -0800, Kees Cook wrote: > On Sun, Jan 08, 2023 at 02:08:52PM +0200, Leon Romanovsky wrote: > > On Thu, Jan 05, 2023 at 02:32:32PM -0800, Kees Cook wrote: > > > Zero-length arrays are deprecated[1]. Replace all remaining > > > 0-length arrays with flexible arrays. Detected with GCC 13, using > > > -fstrict-flex-arrays=3: > > > > > > In function 'build_rdma_write', > > > inlined from 'c4iw_post_send' at ../drivers/infiniband/hw/cxgb4/qp.c:1173:10: > > > ../drivers/infiniband/hw/cxgb4/qp.c:597:38: warning: array subscript 0 is outside array bounds of 'struct fw_ri_immd[0]' [-Warray-bounds=] > > > 597 | wqe->write.u.immd_src[0].r2 = 0; > > > | ~~~~~~~~~~~~~~~~~~~~~^~~ > > > ../drivers/infiniband/hw/cxgb4/t4fw_ri_api.h: In function 'c4iw_post_send': > > > ../drivers/infiniband/hw/cxgb4/t4fw_ri_api.h:567:35: note: while referencing 'immd_src' > > > 567 | struct fw_ri_immd immd_src[0]; > > > | ^~~~~~~~ > > > > > > Additionally drop the unused C99_NOT_SUPPORTED ifndef lines. > > > > > > [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays > > > > > > Cc: Potnuri Bharat Teja <bharat@xxxxxxxxxxx> > > > Cc: Jason Gunthorpe <jgg@xxxxxxxx> > > > Cc: Leon Romanovsky <leon@xxxxxxxxxx> > > > Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx> > > > Cc: linux-rdma@xxxxxxxxxxxxxxx > > > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> > > > --- > > > drivers/infiniband/hw/cxgb4/t4fw_ri_api.h | 26 ++++++----------------- > > > 1 file changed, 6 insertions(+), 20 deletions(-) > > > > <...> > > > > > #define FW_RI_SEND_WR_SENDOP_S 0 > > > @@ -618,12 +606,10 @@ struct fw_ri_rdma_write_cmpl_wr { > > > struct fw_ri_isgl isgl_src; > > > } u_cmpl; > > > __be64 r3; > > > -#ifndef C99_NOT_SUPPORTED > > > union fw_ri_write { > > > - struct fw_ri_immd immd_src[0]; > > > - struct fw_ri_isgl isgl_src[0]; > > > + DECLARE_FLEX_ARRAY(struct fw_ri_immd, immd_src); > > > + DECLARE_FLEX_ARRAY(struct fw_ri_isgl, isgl_src); > > > > smatch built from commit 40351132df3b ("strlen: add __builtin and > > __fortify functions") produces the following warning: > > drivers/infiniband/hw/cxgb4/t4fw_ri_api.h:575:17: warning: array of flexible structures > > > > Is it expected? What will prevent from getting this warning from 0-day > > build bots? > > Err, I'm not sure I understand? Does smatch define "C99_NOT_SUPPORTED"? Why should it define? You removed C99_NOT_SUPPORTED. Just download smatch, build from scratch and run over this patch. It generates new warning. ➜ kernel git:(wip/leon-for-next) mkt ci --no-sparse --no-extra-warnings ccdbefcf661e (HEAD -> build) RDMA/cxgb4: Replace 0-length arrays with flexible arrays WARNING: Possible unwrapped commit description (prefer a maximum 75 chars per line) #11: inlined from 'c4iw_post_send' at ../drivers/infiniband/hw/cxgb4/qp.c:1173:10: drivers/infiniband/hw/cxgb4/t4fw_ri_api.h:558:17: warning: array of flexible structures .... > > -- > Kees Cook
