1*87634653SAndreas Hindborg // SPDX-License-Identifier: GPL-2.0 2*87634653SAndreas Hindborg 3*87634653SAndreas Hindborg #include <linux/build_bug.h> 4*87634653SAndreas Hindborg 5*87634653SAndreas Hindborg /* 6*87634653SAndreas Hindborg * `bindgen` binds the C `size_t` type as the Rust `usize` type, so we can 7*87634653SAndreas Hindborg * use it in contexts where Rust expects a `usize` like slice (array) indices. 8*87634653SAndreas Hindborg * `usize` is defined to be the same as C's `uintptr_t` type (can hold any 9*87634653SAndreas Hindborg * pointer) but not necessarily the same as `size_t` (can hold the size of any 10*87634653SAndreas Hindborg * single object). Most modern platforms use the same concrete integer type for 11*87634653SAndreas Hindborg * both of them, but in case we find ourselves on a platform where 12*87634653SAndreas Hindborg * that's not true, fail early instead of risking ABI or 13*87634653SAndreas Hindborg * integer-overflow issues. 14*87634653SAndreas Hindborg * 15*87634653SAndreas Hindborg * If your platform fails this assertion, it means that you are in 16*87634653SAndreas Hindborg * danger of integer-overflow bugs (even if you attempt to add 17*87634653SAndreas Hindborg * `--no-size_t-is-usize`). It may be easiest to change the kernel ABI on 18*87634653SAndreas Hindborg * your platform such that `size_t` matches `uintptr_t` (i.e., to increase 19*87634653SAndreas Hindborg * `size_t`, because `uintptr_t` has to be at least as big as `size_t`). 20*87634653SAndreas Hindborg */ 21*87634653SAndreas Hindborg static_assert( 22*87634653SAndreas Hindborg sizeof(size_t) == sizeof(uintptr_t) && 23*87634653SAndreas Hindborg __alignof__(size_t) == __alignof__(uintptr_t), 24*87634653SAndreas Hindborg "Rust code expects C `size_t` to match Rust `usize`" 25*87634653SAndreas Hindborg ); 26