On Wed, Apr 26, 2023 at 10:36 AM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote: > > On Wed, Apr 26, 2023 at 10:34 AM Nick Desaulniers > <ndesaulniers@xxxxxxxxxx> wrote: > > > > On Wed, Apr 26, 2023 at 10:03 AM Linus Torvalds > > <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > > > > > > On Mon, Apr 24, 2023 at 9:18 PM Theodore Ts'o <tytso@xxxxxxx> wrote: > > > > > > > > Please note that after merging the mm and ext4 trees you will need to > > > > apply the patch found here[1]. > > > > > > > > [1] https://lore.kernel.org/r/20230419120923.3152939-1-willy@xxxxxxxxxxxxx > > > > > > > > This is due to a patch in the mm tree, "mm: return an ERR_PTR from > > > > __filemap_get_folio" changing that function to returning an ERR_PTR > > > > instead of returning NULL on an error. > > > > > > Side note, itr would be wonderful if we could mark the places that > > > return an error pointer as returning "nonnull", and catch things like > > > this automatically at build time where people compare an error pointer > > > to NULL. > > > > That's what clang's _Nonnull attribute does (with -Wnullability-extension). > > https://godbolt.org/z/6jo1zbMd9 > > Ah sorry, I _thought_ that's how _Nonnull worked on return types. Let > me dig some more and see how that's supposed to work... I guess this is how I'd have expected _Nonnull to work on return types. https://godbolt.org/z/Yb7PdWv8q I'll check with the team to see if there's interest in expanding this check. Would be nice to have a GNU C __attribute__ syntax for this as well, for eventual portability. -- Thanks, ~Nick Desaulniers
