From 0ec321f7b541fcbfbf20286beb497e6d9d3352b2 Mon Sep 17 00:00:00 2001 From: Alex Crichton Date: Fri, 8 Apr 2016 16:18:40 -0700 Subject: rustc: Implement custom panic runtimes This commit is an implementation of [RFC 1513] which allows applications to alter the behavior of panics at compile time. A new compiler flag, `-C panic`, is added and accepts the values `unwind` or `panic`, with the default being `unwind`. This model affects how code is generated for the local crate, skipping generation of landing pads with `-C panic=abort`. [RFC 1513]: https://github.com/rust-lang/rfcs/blob/master/text/1513-less-unwinding.md Panic implementations are then provided by crates tagged with `#![panic_runtime]` and lazily required by crates with `#![needs_panic_runtime]`. The panic strategy (`-C panic` value) of the panic runtime must match the final product, and if the panic strategy is not `abort` then the entire DAG must have the same panic strategy. With the `-C panic=abort` strategy, users can expect a stable method to disable generation of landing pads, improving optimization in niche scenarios, decreasing compile time, and decreasing output binary size. With the `-C panic=unwind` strategy users can expect the existing ability to isolate failure in Rust code from the outside world. Organizationally, this commit dismantles the `sys_common::unwind` module in favor of some bits moving part of it to `libpanic_unwind` and the rest into the `panicking` module in libstd. The custom panic runtime support is pretty similar to the custom allocator support with the only major difference being how the panic runtime is injected (takes the `-C panic` flag into account). --- src/libstd/panic.rs | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) (limited to 'src/libstd/panic.rs') diff --git a/src/libstd/panic.rs b/src/libstd/panic.rs index bbd89af01a7..9a195d93afd 100644 --- a/src/libstd/panic.rs +++ b/src/libstd/panic.rs @@ -16,10 +16,10 @@ use any::Any; use boxed::Box; use cell::UnsafeCell; use ops::{Deref, DerefMut}; +use panicking; use ptr::{Unique, Shared}; use rc::Rc; use sync::{Arc, Mutex, RwLock}; -use sys_common::unwind; use thread::Result; #[unstable(feature = "panic_handler", issue = "30449")] @@ -383,12 +383,9 @@ impl R> FnOnce<()> for AssertRecoverSafe { /// ``` #[stable(feature = "catch_unwind", since = "1.9.0")] pub fn catch_unwind R + UnwindSafe, R>(f: F) -> Result { - let mut result = None; unsafe { - let result = &mut result; - unwind::try(move || *result = Some(f()))? + panicking::try(f) } - Ok(result.unwrap()) } /// Deprecated, renamed to `catch_unwind` @@ -425,7 +422,7 @@ pub fn recover R + UnwindSafe, R>(f: F) -> Result { /// ``` #[stable(feature = "resume_unwind", since = "1.9.0")] pub fn resume_unwind(payload: Box) -> ! { - unwind::rust_panic(payload) + panicking::rust_panic(payload) } /// Deprecated, use resume_unwind instead -- cgit 1.4.1-3-g733a5