1 // Copyright 2016 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! Implementation of panics via stack unwinding
13 //! This crate is an implementation of panics in Rust using "most native" stack
14 //! unwinding mechanism of the platform this is being compiled for. This
15 //! essentially gets categorized into three buckets currently:
17 //! 1. MSVC targets use SEH in the `seh.rs` file.
18 //! 2. The 64-bit MinGW target half-uses SEH and half-use gcc-like information
19 //! in the `seh64_gnu.rs` module.
20 //! 3. All other targets use libunwind/libgcc in the `gcc/mod.rs` module.
22 //! More documentation about each implementation can be found in the respective
26 #![unstable(feature = "panic_unwind", issue = "32837")]
27 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
28 html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
29 html_root_url = "https://doc.rust-lang.org/nightly/",
30 issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/")]
32 #![feature(allocator_api)]
34 #![feature(core_intrinsics)]
35 #![feature(lang_items)]
37 #![feature(panic_unwind)]
39 #![feature(staged_api)]
40 #![feature(std_internals)]
41 #![feature(unwind_attributes)]
42 #![cfg_attr(target_env = "msvc", feature(raw))]
45 #![feature(panic_runtime)]
49 #[cfg(not(any(target_env = "msvc", all(windows, target_arch = "x86_64", target_env = "gnu"))))]
52 use alloc::boxed::Box;
56 use core::panic::BoxMeUp;
58 // Rust runtime's startup objects depend on these symbols, so make them public.
59 #[cfg(all(target_os="windows", target_arch = "x86", target_env="gnu"))]
60 pub use imp::eh_frame_registry::*;
63 #[cfg(target_env = "msvc")]
67 // x86_64-pc-windows-gnu
68 #[cfg(all(windows, target_arch = "x86_64", target_env = "gnu"))]
69 #[path = "seh64_gnu.rs"]
72 // i686-pc-windows-gnu and all others
73 #[cfg(any(all(unix, not(target_os = "emscripten")),
74 target_os = "cloudabi",
76 all(windows, target_arch = "x86", target_env = "gnu")))]
81 #[cfg(target_os = "emscripten")]
85 #[cfg(all(target_arch = "wasm32", not(target_os = "emscripten")))]
92 // Entry point for catching an exception, implemented using the `try` intrinsic
95 // The interaction between the `payload` function and the compiler is pretty
96 // hairy and tightly coupled, for more information see the compiler's
97 // implementation of this.
99 pub unsafe extern "C" fn __rust_maybe_catch_panic(f: fn(*mut u8),
101 data_ptr: *mut usize,
102 vtable_ptr: *mut usize)
104 let mut payload = imp::payload();
105 if intrinsics::try(f, data, &mut payload as *mut _ as *mut _) == 0 {
108 let obj = mem::transmute::<_, raw::TraitObject>(imp::cleanup(payload));
109 *data_ptr = obj.data as usize;
110 *vtable_ptr = obj.vtable as usize;
115 // Entry point for raising an exception, just delegates to the platform-specific
119 pub unsafe extern "C" fn __rust_start_panic(payload: usize) -> u32 {
120 let payload = payload as *mut &mut dyn BoxMeUp;
121 imp::panic(Box::from_raw((*payload).box_me_up()))