On Thu, Mar 28, 2024 at 03:30:45PM +0100, Arnd Bergmann wrote: > From: Arnd Bergmann <arnd@xxxxxxxx> > > clang warns for comparisons that are always true, which is the case > for these two page size checks on architectures with 64KB pages: > > drivers/infiniband/core/uverbs_ioctl.c:90:39: error: result of comparison of constant 65536 with expression of type 'u16' (aka 'unsigned short') is always false [-Werror,-Wtautological-constant-out-of-range-compare] > WARN_ON_ONCE(method_elm->bundle_size > PAGE_SIZE); > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~ > include/asm-generic/bug.h:104:25: note: expanded from macro 'WARN_ON_ONCE' > int __ret_warn_on = !!(condition); \ > ^~~~~~~~~ > drivers/infiniband/core/uverbs_ioctl.c:621:17: error: result of comparison of constant 65536 with expression of type '__u16' (aka 'unsigned short') is always false [-Werror,-Wtautological-constant-out-of-range-compare] > if (hdr.length > PAGE_SIZE || > ~~~~~~~~~~ ^ ~~~~~~~~~ > > Add a cast to u32 in both cases, so it never warns about this. But doesn't that hurt the codegen? Jason
