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? Thanks > } u; > -#endif > }; > > struct fw_ri_rdma_read_wr { > -- > 2.34.1 >
