From 9e224c2bf18ebf8f871efb2e1aba43ed7970ebb7 Mon Sep 17 00:00:00 2001 From: Alex Crichton Date: Fri, 19 Dec 2014 11:29:39 -0800 Subject: std: Re-enable at_exit() The new semantics of this function are that the callbacks are run when the *main thread* exits, not when all threads have exited. This implies that other threads may still be running when the `at_exit` callbacks are invoked and users need to be prepared for this situation. Users in the standard library have been audited in accordance to these new rules as well. Closes #20012 --- src/libstd/rt/unwind.rs | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) (limited to 'src/libstd/rt/unwind.rs') diff --git a/src/libstd/rt/unwind.rs b/src/libstd/rt/unwind.rs index 9b57dcc9e18..32fa126ded4 100644 --- a/src/libstd/rt/unwind.rs +++ b/src/libstd/rt/unwind.rs @@ -68,7 +68,7 @@ use intrinsics; use libc::c_void; use mem; use sync::atomic; -use sync::{Once, ONCE_INIT}; +use sys_common::mutex::{Mutex, MUTEX_INIT}; use rt::libunwind as uw; @@ -587,11 +587,20 @@ pub fn begin_unwind(msg: M, file_line: &(&'static str, uint)) -> /// Doing this split took the LLVM IR line counts of `fn main() { panic!() /// }` from ~1900/3700 (-O/no opts) to 180/590. #[inline(never)] #[cold] // this is the slow path, please never inline this -fn begin_unwind_inner(msg: Box, file_line: &(&'static str, uint)) -> ! { +fn begin_unwind_inner(msg: Box, + file_line: &(&'static str, uint)) -> ! { // Make sure the default failure handler is registered before we look at the // callbacks. - static INIT: Once = ONCE_INIT; - INIT.doit(|| unsafe { register(failure::on_fail); }); + unsafe { + static LOCK: Mutex = MUTEX_INIT; + static mut INIT: bool = false; + LOCK.lock(); + if !INIT { + register(failure::on_fail); + INIT = true; + } + LOCK.unlock(); + } // First, invoke call the user-defined callbacks triggered on thread panic. // -- cgit 1.4.1-3-g733a5