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    SubjectRe: [BUG] [5.15] Compilation error in arch/x86/kvm/mmu/spte.h with clang-14
    On Mon, Oct 4, 2021 at 2:49 AM Paolo Bonzini <pbonzini@redhat.com> wrote:
    >
    > On 04/10/21 11:30, torvic9@mailbox.org wrote:
    > >
    > >> Paolo Bonzini <pbonzini@redhat.com> hat am 04.10.2021 11:26 geschrieben:
    > >>
    > >>
    > >> On 04/10/21 11:08, torvic9@mailbox.org 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

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