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//! This module contains type aliases for C's platform-specific types
//! and fixed-width integer types.
//!
//! The platform-specific types definitions were taken from rust-lang/rust in
//! library/core/src/ffi/primitives.rs
//!
//! The fixed-width integer aliases are deprecated: use the Rust types instead.
pub type c_schar = i8;
pub type c_uchar = u8;
pub type c_short = i16;
pub type c_ushort = u16;
pub type c_longlong = i64;
pub type c_ulonglong = u64;
pub type c_float = f32;
pub type c_double = f64;
cfg_if! {
if #[cfg(all(
not(windows),
// FIXME(ctest): just use `target_vendor` = "apple"` once `ctest` supports it
not(any(
target_os = "macos",
target_os = "ios",
target_os = "tvos",
target_os = "watchos",
target_os = "visionos",
)),
not(target_os = "vita"),
any(
target_arch = "aarch64",
target_arch = "arm",
target_arch = "csky",
target_arch = "hexagon",
target_arch = "msp430",
target_arch = "powerpc",
target_arch = "powerpc64",
target_arch = "riscv32",
target_arch = "riscv64",
target_arch = "s390x",
target_arch = "xtensa",
)
))] {
pub type c_char = u8;
} else {
// On every other target, c_char is signed.
pub type c_char = i8;
}
}
cfg_if! {
if #[cfg(any(target_arch = "avr", target_arch = "msp430"))] {
pub type c_int = i16;
pub type c_uint = u16;
} else {
pub type c_int = i32;
pub type c_uint = u32;
}
}
cfg_if! {
if #[cfg(all(target_pointer_width = "64", not(windows)))] {
pub type c_long = i64;
pub type c_ulong = u64;
} else {
// The minimal size of `long` in the C standard is 32 bits
pub type c_long = i32;
pub type c_ulong = u32;
}
}
#[deprecated(since = "0.2.55", note = "Use i8 instead.")]
pub type int8_t = i8;
#[deprecated(since = "0.2.55", note = "Use i16 instead.")]
pub type int16_t = i16;
#[deprecated(since = "0.2.55", note = "Use i32 instead.")]
pub type int32_t = i32;
#[deprecated(since = "0.2.55", note = "Use i64 instead.")]
pub type int64_t = i64;
#[deprecated(since = "0.2.55", note = "Use u8 instead.")]
pub type uint8_t = u8;
#[deprecated(since = "0.2.55", note = "Use u16 instead.")]
pub type uint16_t = u16;
#[deprecated(since = "0.2.55", note = "Use u32 instead.")]
pub type uint32_t = u32;
#[deprecated(since = "0.2.55", note = "Use u64 instead.")]
pub type uint64_t = u64;
cfg_if! {
if #[cfg(all(target_arch = "aarch64", not(target_os = "windows")))] {
// This introduces partial support for FFI with __int128 and
// equivalent types on platforms where Rust's definition is validated
// to match the standard C ABI of that platform.
//
// Rust does not guarantee u128/i128 are sound for FFI, and its
// definitions are in fact known to be incompatible. [0]
//
// However these problems aren't fundamental, and are just platform
// inconsistencies. Specifically at the time of this writing:
//
// * For x64 SysV ABIs (everything but Windows), the types are underaligned.
// * For all Windows ABIs, Microsoft doesn't actually officially define __int128,
// and as a result different implementations don't actually agree on its ABI.
//
// But on the other major aarch64 platforms (android, linux, ios, macos) we have
// validated that rustc has the right ABI for these types. This is important because
// aarch64 uses these types in some fundamental OS types like user_fpsimd_struct,
// which represents saved simd registers.
//
// Any API which uses these types will need to `#[ignore(improper_ctypes)]`
// until the upstream rust issue is resolved, but this at least lets us make
// progress on platforms where this type is important.
//
// The list of supported architectures and OSes is intentionally very restricted,
// as careful work needs to be done to verify that a particular platform
// has a conformant ABI.
//
/// C `__int128` (a GCC extension that's part of many ABIs)
pub type __int128 = i128;
/// C `unsigned __int128` (a GCC extension that's part of many ABIs)
pub type __uint128 = u128;
/// C __int128_t (alternate name for [__int128][])
pub type __int128_t = i128;
/// C __uint128_t (alternate name for [__uint128][])
pub type __uint128_t = u128;
// NOTE: if you add more platforms to here, you may need to cfg
// these consts. They should always match the platform's values
// for `sizeof(__int128)` and `_Alignof(__int128)`.
const _SIZE_128: usize = 16;
const _ALIGN_128: usize = 16;
// FIXME(ctest): ctest doesn't handle `_` as an identifier so these tests are temporarily
// disabled.
// macro_rules! static_assert_eq {
// ($a:expr, $b:expr) => {
// const _: [(); $a] = [(); $b];
// };
// }
//
// // Since Rust doesn't officially guarantee that these types
// // have compatible ABIs, we const assert that these values have the
// // known size/align of the target platform's libc. If rustc ever
// // tries to regress things, it will cause a compilation error.
// //
// // This isn't a bullet-proof solution because e.g. it doesn't
// // catch the fact that llvm and gcc disagree on how x64 __int128
// // is actually *passed* on the stack (clang underaligns it for
// // the same reason that rustc *never* properly aligns it).
// static_assert_eq!(core::mem::size_of::<__int128>(), _SIZE_128);
// static_assert_eq!(core::mem::align_of::<__int128>(), _ALIGN_128);
// static_assert_eq!(core::mem::size_of::<__uint128>(), _SIZE_128);
// static_assert_eq!(core::mem::align_of::<__uint128>(), _ALIGN_128);
// static_assert_eq!(core::mem::size_of::<__int128_t>(), _SIZE_128);
// static_assert_eq!(core::mem::align_of::<__int128_t>(), _ALIGN_128);
// static_assert_eq!(core::mem::size_of::<__uint128_t>(), _SIZE_128);
// static_assert_eq!(core::mem::align_of::<__uint128_t>(), _ALIGN_128);
}
}