On 5/5/20 10:00, Arnd Bergmann wrote: > On Tue, May 5, 2020 at 4:35 PM Gustavo A. R. Silva > <gustavo@xxxxxxxxxxxxxx> wrote: >> On 5/5/20 09:30, Arnd Bergmann wrote: >>> gcc-10 warns about accesses into the f_handle[] zero-length array. >>> >>> fs/notify/fdinfo.c: In function 'show_mark_fhandle': >>> fs/notify/fdinfo.c:66:47: error: array subscript 'i' is outside the bounds of an interior zero-length array 'unsigned char[0]' [-Werror=zero-length-bounds] >>> 66 | seq_printf(m, "%02x", (int)f.handle.f_handle[i]); >>> | ~~~~~~~~~~~~~~~~~^~~ >>> In file included from fs/notify/fdinfo.c:3: >>> include/linux/fs.h:988:16: note: while referencing 'f_handle' >>> 988 | unsigned char f_handle[0]; >>> | ^~~~~~~~ >>> >>> This is solved by using a flexible array instead. >>> >>> Cc: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx> >>> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> >>> --- >>> Gustavo has done the same thing as part of a treewide change, but keeping >>> this separate lets us backport it to stable kernels more easily later. >> >> Arnd, >> >> I wonder why would we need to backport these changes to -stable... merely >> because of the use of a new version of GCC? > > Yes, we usually backport trivial warning fixes to stable kernels to allow > building those with any modern compiler version. > OK. So, if you anticipate that this is going to happen, I can split up my treewide patch into separate per-subsystem patches. I can replace the treewide patch in my tree today, so the changes are reflected in tomorrow's linux-next. -- Gustavo
