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1// SPDX-License-Identifier: GPL-2.02 3#include <linux/build_bug.h>4 5/*6 * `bindgen` binds the C `size_t` type as the Rust `usize` type, so we can7 * use it in contexts where Rust expects a `usize` like slice (array) indices.8 * `usize` is defined to be the same as C's `uintptr_t` type (can hold any9 * pointer) but not necessarily the same as `size_t` (can hold the size of any10 * single object). Most modern platforms use the same concrete integer type for11 * both of them, but in case we find ourselves on a platform where12 * that's not true, fail early instead of risking ABI or13 * integer-overflow issues.14 *15 * If your platform fails this assertion, it means that you are in16 * danger of integer-overflow bugs (even if you attempt to add17 * `--no-size_t-is-usize`). It may be easiest to change the kernel ABI on18 * your platform such that `size_t` matches `uintptr_t` (i.e., to increase19 * `size_t`, because `uintptr_t` has to be at least as big as `size_t`).20 */21static_assert(22 sizeof(size_t) == sizeof(uintptr_t) &&23 __alignof__(size_t) == __alignof__(uintptr_t),24 "Rust code expects C `size_t` to match Rust `usize`"25);26