On Fri, Dec 13, 2024 at 4:35 AM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > > On Sun, 8 Dec 2024 21:45:15 +0100 Uros Bizjak <ubizjak@xxxxxxxxx> wrote: > > > Enable strict percpu address space checks via x86 named address space > > qualifiers. Percpu variables are declared in __seg_gs/__seg_fs named > > AS and kept named AS qualified until they are dereferenced via percpu > > accessor. This approach enables various compiler checks for > > cross-namespace variable assignments. > > > > Please note that current version of sparse doesn't know anything about > > __typeof_unqual__() operator. Avoid the usage of __typeof_unqual__() > > when sparse checking is active to prevent sparse errors with unknowing > > keyword. The proposed patch by Dan Carpenter to implement > > __typeof_unqual__() handling in sparse is located at: > > google("what the hell is typeof_unequal") failed me. It is not "typeof_unequal", but "typeof_unqual", as in "unqualified". Apparently, google does not like expletives, googling for "What is typeof_unqual?" returns some very informative hits, e.g.: https://en.cppreference.com/w/c/keyword/typeof_unqual https://learn.microsoft.com/en-us/cpp/c-language/typeof-unqual-c?view=msvc-170 https://gcc.gnu.org/onlinedocs/gcc/Typeof.html https://dev.to/pauljlucas/typeof-in-c23-55p2 > I think it would be nice to include within the changelog (and code > comments!) an explanation-for-others of what this thing is and why > anyone would want to use it. Rather than assuming that all kernel > developers are typeof() experts! The comment above definition of TYPEOF_UNQUAL in [PATCH 2/6] summarises the above as: + * Define TYPEOF_UNQUAL() to use __typeof_unqual__() as typeof + * operator when available, to return unqualified type of the exp. which is basically what the standard says in its reference document. Thanks, Uros.