On Mon, Oct 4, 2021 at 2:49 AM Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: > > On 04/10/21 11:30, torvic9@xxxxxxxxxxx wrote: > > > >> Paolo Bonzini <pbonzini@xxxxxxxxxx> hat am 04.10.2021 11:26 geschrieben: > >> > >> > >> On 04/10/21 11:08, torvic9@xxxxxxxxxxx wrote: > >>> I encounter the following issue when compiling 5.15-rc4 with clang-14: > >>> > >>> In file included from arch/x86/kvm/mmu/mmu.c:27: > >>> arch/x86/kvm/mmu/spte.h:318:9: error: use of bitwise '|' with boolean operands [-Werror,-Wbitwise-instead-of-logical] > >>> return __is_bad_mt_xwr(rsvd_check, spte) | > >>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > >>> || > >>> arch/x86/kvm/mmu/spte.h:318:9: note: cast one or both operands to int to silence this warning > >> > >> The warning is wrong, as mentioned in the line right above: > > > > So it's an issue with clang-14 then? > > (I add Nick and Nathan) > > My clang here doesn't have the option, so I'm going to ask---are you > using W=1? I can see why clang is warning for KVM's code, but in my > opinion such a check should only be in -Wextra. This is a newly added warning in top of tree clang. > > Paolo > > >> > >> /* > >> * Use a bitwise-OR instead of a logical-OR to aggregate the reserved > >> * bits and EPT's invalid memtype/XWR checks to avoid an extra Jcc > >> * (this is extremely unlikely to be short-circuited as true). > >> */ > >> > >> Paolo > > > -- Thanks, ~Nick Desaulniers
