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|
#![warn(clippy::transmute_ptr_to_ptr)]
#![allow(clippy::borrow_as_ptr, clippy::missing_transmute_annotations)]
use std::mem::transmute;
// Make sure we can modify lifetimes, which is one of the recommended uses
// of transmute
// Make sure we can do static lifetime transmutes
unsafe fn transmute_lifetime_to_static<'a, T>(t: &'a T) -> &'static T {
unsafe { transmute::<&'a T, &'static T>(t) }
}
// Make sure we can do non-static lifetime transmutes
unsafe fn transmute_lifetime<'a, 'b, T>(t: &'a T, u: &'b T) -> &'b T {
unsafe { transmute::<&'a T, &'b T>(t) }
}
struct LifetimeParam<'a> {
s: &'a str,
}
struct GenericParam<T> {
t: T,
}
fn transmute_ptr_to_ptr() {
let ptr = &1u32 as *const u32;
let mut_ptr = &mut 1u32 as *mut u32;
unsafe {
// pointer-to-pointer transmutes; bad
let _: *const f32 = transmute(ptr);
//~^ transmute_ptr_to_ptr
let _: *mut f32 = transmute(mut_ptr);
//~^ transmute_ptr_to_ptr
// ref-ref transmutes; bad
let _: &f32 = transmute(&1u32);
//~^ transmute_ptr_to_ptr
let _: &f32 = transmute(&1f64);
//~^ transmute_ptr_to_ptr
//:^ this test is here because both f32 and f64 are the same TypeVariant, but they are not
// the same type
let _: &mut f32 = transmute(&mut 1u32);
//~^ transmute_ptr_to_ptr
let _: &GenericParam<f32> = transmute(&GenericParam { t: 1u32 });
//~^ transmute_ptr_to_ptr
let u64_ref: &u64 = &0u64;
let u8_ref: &u8 = transmute(u64_ref);
//~^ transmute_ptr_to_ptr
let _: *const u32 = transmute(mut_ptr);
//~^ transmute_ptr_to_ptr
let _: *mut u32 = transmute(ptr);
//~^ transmute_ptr_to_ptr
}
// transmute internal lifetimes, should not lint
let s = "hello world".to_owned();
let lp = LifetimeParam { s: &s };
let _: &LifetimeParam<'static> = unsafe { transmute(&lp) };
let _: &GenericParam<&LifetimeParam<'static>> = unsafe { transmute(&GenericParam { t: &lp }) };
}
fn lifetime_to_static(v: *mut &()) -> *const &'static () {
unsafe { transmute(v) }
//~^ transmute_ptr_to_ptr
}
// dereferencing raw pointers in const contexts, should not lint as it's unstable (issue 5959)
const _: &() = {
struct Zst;
let zst = &Zst;
unsafe { transmute::<&'static Zst, &'static ()>(zst) }
};
#[clippy::msrv = "1.37"]
fn msrv_1_37(ptr: *const u8) {
unsafe {
let _: *const i8 = transmute(ptr);
//~^ transmute_ptr_to_ptr
}
}
#[clippy::msrv = "1.38"]
fn msrv_1_38(ptr: *const u8) {
unsafe {
let _: *const i8 = transmute(ptr);
//~^ transmute_ptr_to_ptr
}
}
#[clippy::msrv = "1.64"]
fn msrv_1_64(ptr: *const u8, mut_ptr: *mut u8) {
unsafe {
let _: *mut u8 = transmute(ptr);
//~^ transmute_ptr_to_ptr
let _: *const u8 = transmute(mut_ptr);
//~^ transmute_ptr_to_ptr
}
}
#[clippy::msrv = "1.65"]
fn msrv_1_65(ptr: *const u8, mut_ptr: *mut u8) {
unsafe {
let _: *mut u8 = transmute(ptr);
//~^ transmute_ptr_to_ptr
let _: *const u8 = transmute(mut_ptr);
//~^ transmute_ptr_to_ptr
}
}
fn main() {}
|
