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    SubjectRe: [PATCH] genksyms: Ignore module scoped _Static_assert()
    On Tue, Dec 01, 2020 at 04:14PM +0000, Christoph Hellwig wrote:
    > Why not use the kernels own BUILD_BUG_ON instead of this idiom?

    BUILD_BUG_ON() was conceived before there was builtin compiler-support
    in the form of _Static_assert() (static_assert()), which has several
    advantages (compile-time performance, optional message) but most
    importantly, that it can be used at module/global scope (which
    BUILD_BUG_ON() cannot).

    From include/linux/build_bug:

    /**
    * static_assert - check integer constant expression at build time
    *
    [...]
    *
    * Contrary to BUILD_BUG_ON(), static_assert() can be used at global
    * scope, but requires the expression to be an integer constant
    * expression (i.e., it is not enough that __builtin_constant_p() is
    * true for expr).
    [...]

    .. and there are plenty of global/module scoped users of it already.

    Thanks,
    -- Marco

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