rust/tests/codegen/unwind-abis/nounwind.rs

// compile-flags: -C opt-level=0 -Cpanic=abort
// ignore-wasm32-bare compiled with panic=abort by default

#![crate_type = "lib"]
#![feature(c_unwind)]

// We disable optimizations to prevent LLVM from inferring the attribute.

// CHECK: Function Attrs:{{.*}}nounwind
// CHECK-NEXT: @foo
#[no_mangle]
pub extern "C" fn foo() {}

// CHECK: Function Attrs:{{.*}}nounwind
// CHECK-NEXT: @bar
#[no_mangle]
pub fn bar() {}
rustc: Fill out remaining parts of C-unwind ABI This commit intends to fill out some of the remaining pieces of the C-unwind ABI. This has a number of other changes with it though to move this design space forward a bit. Notably contained within here is: * On `panic=unwind`, the `extern "C"` ABI is now considered as "may unwind". This fixes a longstanding soundness issue where if you `panic!()` in an `extern "C"` function defined in Rust that's actually UB because the LLVM representation for the function has the `nounwind` attribute, but then you unwind. * Whether or not a function unwinds now mainly considers the ABI of the function instead of first checking the panic strategy. This fixes a miscompile of `extern "C-unwind"` with `panic=abort` because that ABI can still unwind. * The aborting stub for non-unwinding ABIs with `panic=unwind` has been reimplemented. Previously this was done as a small tweak during MIR generation, but this has been moved to a separate and dedicated MIR pass. This new pass will, for appropriate functions and function calls, insert a `cleanup` landing pad for any function call that may unwind within a function that is itself not allowed to unwind. Note that this subtly changes some behavior from before where previously on an unwind which was caught-to-abort it would run active destructors in the function, and now it simply immediately aborts the process. * The `#[unwind]` attribute has been removed and all users in tests and such are now using `C-unwind` and `#![feature(c_unwind)]`. I think this is largely the last piece of the RFC to implement. Unfortunately I believe this is still not stabilizable as-is because activating the feature gate changes the behavior of the existing `extern "C"` ABI in a way that has no replacement. My thinking for how to enable this is that we add support for the `C-unwind` ABI on stable Rust first, and then after it hits stable we change the behavior of the `C` ABI. That way anyone straddling stable/beta/nightly can switch to `C-unwind` safely. 2021-06-08 13:23:58 -05:00			`// compile-flags: -C opt-level=0 -Cpanic=abort`
			`// ignore-wasm32-bare compiled with panic=abort by default`

			`#![crate_type = "lib"]`
			`#![feature(c_unwind)]`

Fix a bunch of typo This PR will fix some typos detected by [typos]. I only picked the ones I was sure were spelling errors to fix, mostly in the comments. [typos]: https://github.com/crate-ci/typos 2022-08-17 21:13:37 -05:00			`// We disable optimizations to prevent LLVM from inferring the attribute.`
rustc: Fill out remaining parts of C-unwind ABI This commit intends to fill out some of the remaining pieces of the C-unwind ABI. This has a number of other changes with it though to move this design space forward a bit. Notably contained within here is: * On `panic=unwind`, the `extern "C"` ABI is now considered as "may unwind". This fixes a longstanding soundness issue where if you `panic!()` in an `extern "C"` function defined in Rust that's actually UB because the LLVM representation for the function has the `nounwind` attribute, but then you unwind. * Whether or not a function unwinds now mainly considers the ABI of the function instead of first checking the panic strategy. This fixes a miscompile of `extern "C-unwind"` with `panic=abort` because that ABI can still unwind. * The aborting stub for non-unwinding ABIs with `panic=unwind` has been reimplemented. Previously this was done as a small tweak during MIR generation, but this has been moved to a separate and dedicated MIR pass. This new pass will, for appropriate functions and function calls, insert a `cleanup` landing pad for any function call that may unwind within a function that is itself not allowed to unwind. Note that this subtly changes some behavior from before where previously on an unwind which was caught-to-abort it would run active destructors in the function, and now it simply immediately aborts the process. * The `#[unwind]` attribute has been removed and all users in tests and such are now using `C-unwind` and `#![feature(c_unwind)]`. I think this is largely the last piece of the RFC to implement. Unfortunately I believe this is still not stabilizable as-is because activating the feature gate changes the behavior of the existing `extern "C"` ABI in a way that has no replacement. My thinking for how to enable this is that we add support for the `C-unwind` ABI on stable Rust first, and then after it hits stable we change the behavior of the `C` ABI. That way anyone straddling stable/beta/nightly can switch to `C-unwind` safely. 2021-06-08 13:23:58 -05:00
			`// CHECK: Function Attrs:{{.*}}nounwind`
			`// CHECK-NEXT: @foo`
			`#[no_mangle]`
			`pub extern "C" fn foo() {}`

			`// CHECK: Function Attrs:{{.*}}nounwind`
			`// CHECK-NEXT: @bar`
			`#[no_mangle]`
			`pub fn bar() {}`