rust/src/test/ui/unsafe/unsafe-around-compiler-generated-unsafe.rs

// edition:2018
// revisions: mir thir
// [thir]compile-flags: -Z thir-unsafeck

#![deny(unused_unsafe)]

fn main() {
    let _ = async {
        unsafe { async {}.await; } //~ ERROR unnecessary `unsafe`
    };
}
Fix unused_unsafe with compiler-generated unsafe 2021-04-29 20:54:22 -05:00			`// edition:2018`
Test `-Zthir-unsafeck` for unused unsafe blocks 2021-03-14 22:25:42 +01:00			`// revisions: mir thir`
			`// [thir]compile-flags: -Z thir-unsafeck`

Convert most code to new inner attribute syntax. Closes #2569 2014-03-21 18:05:05 -07:00			`#![deny(unused_unsafe)]`
rustc: avoid compiler generated `unsafe` blocks leaking. Previously an `unsafe` block created by the compiler (like those in the formatting macros) would be "ignored" if surrounded by `unsafe`, that is, the internal unsafety would be being legitimised by the external block: unsafe { println!("...") } =(expansion)=> unsafe { ... unsafe { ... } } And the code in the inner block would be using the outer block, making it considered used (and the inner one considered unused). This patch forces the compiler to create a new unsafe context for compiler generated blocks, so that their internal unsafety doesn't escape to external blocks. Fixes #12418. 2014-02-20 23:22:45 +11:00
			`fn main() {`
Fix unused_unsafe with compiler-generated unsafe 2021-04-29 20:54:22 -05:00			`let _ = async {`
			unsafe { async {}.await; } //~ ERROR unnecessary `unsafe`
			`};`
rustc: avoid compiler generated `unsafe` blocks leaking. Previously an `unsafe` block created by the compiler (like those in the formatting macros) would be "ignored" if surrounded by `unsafe`, that is, the internal unsafety would be being legitimised by the external block: unsafe { println!("...") } =(expansion)=> unsafe { ... unsafe { ... } } And the code in the inner block would be using the outer block, making it considered used (and the inner one considered unused). This patch forces the compiler to create a new unsafe context for compiler generated blocks, so that their internal unsafety doesn't escape to external blocks. Fixes #12418. 2014-02-20 23:22:45 +11:00			`}`