From cbfa61282fc34204b9b66554e06189c2d0b4d085 Mon Sep 17 00:00:00 2001 From: Andrea Canciani Date: Tue, 22 Sep 2015 08:40:15 +0200 Subject: [PATCH] Simplify on_panic callback handling The registration of `panicking::on_panic` as a general-purpose callback is overcomplicated and can fail. Instead, invoking it explicitly removes the need for locking and paves the way for further improvements. --- src/libstd/sys/common/unwind/mod.rs | 21 +++++---------------- 1 file changed, 5 insertions(+), 16 deletions(-) diff --git a/src/libstd/sys/common/unwind/mod.rs b/src/libstd/sys/common/unwind/mod.rs index 738681c3cfed7..47f6bd9315d99 100644 --- a/src/libstd/sys/common/unwind/mod.rs +++ b/src/libstd/sys/common/unwind/mod.rs @@ -244,22 +244,12 @@ pub fn begin_unwind(msg: M, file_line: &(&'static str, u32)) -> ! #[inline(never)] #[cold] // this is the slow path, please never inline this fn begin_unwind_inner(msg: Box, file_line: &(&'static str, u32)) -> ! { - // Make sure the default failure handler is registered before we look at the - // callbacks. We also use a raw sys-based mutex here instead of a - // `std::sync` one as accessing TLS can cause weird recursive problems (and - // we don't need poison checking). - unsafe { - static LOCK: Mutex = Mutex::new(); - static mut INIT: bool = false; - LOCK.lock(); - if !INIT { - register(panicking::on_panic); - INIT = true; - } - LOCK.unlock(); - } + let (file, line) = *file_line; + + // First, invoke the default panic handler. + panicking::on_panic(&*msg, file, line); - // First, invoke call the user-defined callbacks triggered on thread panic. + // Then, invoke call the user-defined callbacks triggered on thread panic. // // By the time that we see a callback has been registered (by reading // MAX_CALLBACKS), the actual callback itself may have not been stored yet, @@ -275,7 +265,6 @@ fn begin_unwind_inner(msg: Box, 0 => {} n => { let f: Callback = unsafe { mem::transmute(n) }; - let (file, line) = *file_line; f(&*msg, file, line); } }