9 files changed, 131 insertions, 31 deletions
diff --git a/src/libstd/sys_common/backtrace.rs b/src/libstd/sys_common/backtrace.rs
index 617218fe7a5..b5cf6d7d34f 100644
--- a/src/libstd/sys_common/backtrace.rs
+++ b/src/libstd/sys_common/backtrace.rs
@@ -8,15 +8,12 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![cfg_attr(target_os = "nacl", allow(dead_code))]
-
 /// Common code for printing the backtrace in the same way across the different
 /// supported platforms.
 
 use env;
 use io::prelude::*;
 use io;
-use libc;
 use str;
 use sync::atomic::{self, Ordering};
 use path::{self, Path};
@@ -41,9 +38,9 @@ pub const HEX_WIDTH: usize = 10;
 #[derive(Debug, Copy, Clone)]
 pub struct Frame {
     /// Exact address of the call that failed.
-    pub exact_position: *const libc::c_void,
+    pub exact_position: *const u8,
     /// Address of the enclosing function.
-    pub symbol_addr: *const libc::c_void,
+    pub symbol_addr: *const u8,
 }
 
 /// Max number of frames to print.
@@ -203,8 +200,10 @@ fn output(w: &mut Write, idx: usize, frame: Frame,
 ///
 /// See also `output`.
 #[allow(dead_code)]
-fn output_fileline(w: &mut Write, file: &[u8], line: libc::c_int,
-                       format: PrintFormat) -> io::Result<()> {
+fn output_fileline(w: &mut Write,
+                   file: &[u8],
+                   line: u32,
+                   format: PrintFormat) -> io::Result<()> {
     // prior line: "  ##: {:2$} - func"
     w.write_all(b"")?;
     match format {
@@ -253,8 +252,26 @@ fn output_fileline(w: &mut Write, file: &[u8], line: libc::c_int,
 // Note that this demangler isn't quite as fancy as it could be. We have lots
 // of other information in our symbols like hashes, version, type information,
 // etc. Additionally, this doesn't handle glue symbols at all.
-pub fn demangle(writer: &mut Write, s: &str, format: PrintFormat) -> io::Result<()> {
-    // First validate the symbol. If it doesn't look like anything we're
+pub fn demangle(writer: &mut Write, mut s: &str, format: PrintFormat) -> io::Result<()> {
+    // During ThinLTO LLVM may import and rename internal symbols, so strip out
+    // those endings first as they're one of the last manglings applied to
+    // symbol names.
+    let llvm = ".llvm.";
+    if let Some(i) = s.find(llvm) {
+        let candidate = &s[i + llvm.len()..];
+        let all_hex = candidate.chars().all(|c| {
+            match c {
+                'A' ... 'F' | '0' ... '9' => true,
+                _ => false,
+            }
+        });
+
+        if all_hex {
+            s = &s[..i];
+        }
+    }
+
+    // Validate the symbol. If it doesn't look like anything we're
     // expecting, we just print it literally. Note that we must handle non-rust
     // symbols because we could have any function in the backtrace.
     let mut valid = true;
diff --git a/src/libstd/sys_common/gnu/libbacktrace.rs b/src/libstd/sys_common/gnu/libbacktrace.rs
index 016c840d154..75c6bd5d2a2 100644
--- a/src/libstd/sys_common/gnu/libbacktrace.rs
+++ b/src/libstd/sys_common/gnu/libbacktrace.rs
@@ -20,13 +20,13 @@ use sys_common::backtrace::Frame;
 pub fn foreach_symbol_fileline<F>(frame: Frame,
                                   mut f: F,
                                   _: &BacktraceContext) -> io::Result<bool>
-where F: FnMut(&[u8], libc::c_int) -> io::Result<()>
+where F: FnMut(&[u8], u32) -> io::Result<()>
 {
     // pcinfo may return an arbitrary number of file:line pairs,
     // in the order of stack trace (i.e. inlined calls first).
     // in order to avoid allocation, we stack-allocate a fixed size of entries.
     const FILELINE_SIZE: usize = 32;
-    let mut fileline_buf = [(ptr::null(), -1); FILELINE_SIZE];
+    let mut fileline_buf = [(ptr::null(), !0); FILELINE_SIZE];
     let ret;
     let fileline_count = {
         let state = unsafe { init_state() };
@@ -136,7 +136,7 @@ extern {
 // helper callbacks
 ////////////////////////////////////////////////////////////////////////
 
-type FileLine = (*const libc::c_char, libc::c_int);
+type FileLine = (*const libc::c_char, u32);
 
 extern fn error_cb(_data: *mut libc::c_void, _msg: *const libc::c_char,
                    _errnum: libc::c_int) {
@@ -162,7 +162,7 @@ extern fn pcinfo_cb(data: *mut libc::c_void,
         // if the buffer is not full, add file:line to the buffer
         // and adjust the buffer for next possible calls to pcinfo_cb.
         if !buffer.is_empty() {
-            buffer[0] = (filename, lineno);
+            buffer[0] = (filename, lineno as u32);
             unsafe { ptr::write(slot, &mut buffer[1..]); }
         }
     }
diff --git a/src/libstd/sys_common/mod.rs b/src/libstd/sys_common/mod.rs
index d7654ce9300..14e5697b94e 100644
--- a/src/libstd/sys_common/mod.rs
+++ b/src/libstd/sys_common/mod.rs
@@ -44,11 +44,15 @@ pub mod thread_local;
 pub mod util;
 pub mod wtf8;
 
-#[cfg(any(target_os = "redox", target_os = "l4re"))]
-pub use sys::net;
-
-#[cfg(not(any(target_os = "redox", target_os = "l4re")))]
-pub mod net;
+cfg_if! {
+    if #[cfg(any(target_os = "redox", target_os = "l4re"))] {
+        pub use sys::net;
+    } else if #[cfg(all(target_arch = "wasm32", not(target_os = "emscripten")))] {
+        pub use sys::net;
+    } else {
+        pub mod net;
+    }
+}
 
 #[cfg(feature = "backtrace")]
 #[cfg(any(all(unix, not(target_os = "emscripten")),
diff --git a/src/libstd/sys_common/net.rs b/src/libstd/sys_common/net.rs
index 19dc841b9b5..c76b0bcf1c9 100644
--- a/src/libstd/sys_common/net.rs
+++ b/src/libstd/sys_common/net.rs
@@ -175,10 +175,15 @@ pub fn lookup_host(host: &str) -> io::Result<LookupHost> {
             },
             #[cfg(unix)]
             Err(e) => {
-                // The lookup failure could be caused by using a stale /etc/resolv.conf.
-                // See https://github.com/rust-lang/rust/issues/41570.
-                // We therefore force a reload of the nameserver information.
-                c::res_init();
+                // If we're running glibc prior to version 2.26, the lookup
+                // failure could be caused by caching a stale /etc/resolv.conf.
+                // We need to call libc::res_init() to clear the cache. But we
+                // shouldn't call it in on any other platform, because other
+                // res_init implementations aren't thread-safe. See
+                // https://github.com/rust-lang/rust/issues/41570 and
+                // https://github.com/rust-lang/rust/issues/43592.
+                use sys::net::res_init_if_glibc_before_2_26;
+                let _ = res_init_if_glibc_before_2_26();
                 Err(e)
             },
             // the cfg is needed here to avoid an "unreachable pattern" warning
diff --git a/src/libstd/sys_common/poison.rs b/src/libstd/sys_common/poison.rs
index 3c61593acc5..934ac3edbf1 100644
--- a/src/libstd/sys_common/poison.rs
+++ b/src/libstd/sys_common/poison.rs
@@ -65,6 +65,31 @@ pub struct Guard {
 /// each lock, but once a lock is poisoned then all future acquisitions will
 /// return this error.
 ///
+/// # Examples
+///
+/// ```
+/// use std::sync::{Arc, Mutex};
+/// use std::thread;
+///
+/// let mutex = Arc::new(Mutex::new(1));
+///
+/// // poison the mutex
+/// let c_mutex = mutex.clone();
+/// let _ = thread::spawn(move || {
+///     let mut data = c_mutex.lock().unwrap();
+///     *data = 2;
+///     panic!();
+/// }).join();
+///
+/// match mutex.lock() {
+///     Ok(_) => unreachable!(),
+///     Err(p_err) => {
+///         let data = p_err.get_ref();
+///         println!("recovered: {}", data);
+///     }
+/// };
+/// ```
+///
 /// [`Mutex`]: ../../std/sync/struct.Mutex.html
 /// [`RwLock`]: ../../std/sync/struct.RwLock.html
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -72,10 +97,16 @@ pub struct PoisonError<T> {
     guard: T,
 }
 
-/// An enumeration of possible errors which can occur while calling the
-/// [`try_lock`] method.
+/// An enumeration of possible errors associated with a [`TryLockResult`] which
+/// can occur while trying to aquire a lock, from the [`try_lock`] method on a
+/// [`Mutex`] or the [`try_read`] and [`try_write`] methods on an [`RwLock`].
 ///
+/// [`Mutex`]: struct.Mutex.html
+/// [`RwLock`]: struct.RwLock.html
+/// [`TryLockResult`]: type.TryLockResult.html
 /// [`try_lock`]: struct.Mutex.html#method.try_lock
+/// [`try_read`]: struct.RwLock.html#method.try_read
+/// [`try_write`]: struct.RwLock.html#method.try_write
 #[stable(feature = "rust1", since = "1.0.0")]
 pub enum TryLockError<T> {
     /// The lock could not be acquired because another thread failed while holding
@@ -148,6 +179,28 @@ impl<T> PoisonError<T> {
 
     /// Consumes this error indicating that a lock is poisoned, returning the
     /// underlying guard to allow access regardless.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::collections::HashSet;
+    /// use std::sync::{Arc, Mutex};
+    /// use std::thread;
+    ///
+    /// let mutex = Arc::new(Mutex::new(HashSet::new()));
+    ///
+    /// // poison the mutex
+    /// let c_mutex = mutex.clone();
+    /// let _ = thread::spawn(move || {
+    ///     let mut data = c_mutex.lock().unwrap();
+    ///     data.insert(10);
+    ///     panic!();
+    /// }).join();
+    ///
+    /// let p_err = mutex.lock().unwrap_err();
+    /// let data = p_err.into_inner();
+    /// println!("recovered {} items", data.len());
+    /// ```
     #[stable(feature = "sync_poison", since = "1.2.0")]
     pub fn into_inner(self) -> T { self.guard }
 
diff --git a/src/libstd/sys_common/remutex.rs b/src/libstd/sys_common/remutex.rs
index 4d0407ccf6c..ce43ec6d9ab 100644
--- a/src/libstd/sys_common/remutex.rs
+++ b/src/libstd/sys_common/remutex.rs
@@ -116,11 +116,18 @@ impl<T> Drop for ReentrantMutex<T> {
 impl<T: fmt::Debug + 'static> fmt::Debug for ReentrantMutex<T> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match self.try_lock() {
-            Ok(guard) => write!(f, "ReentrantMutex {{ data: {:?} }}", &*guard),
+            Ok(guard) => f.debug_struct("ReentrantMutex").field("data", &*guard).finish(),
             Err(TryLockError::Poisoned(err)) => {
-                write!(f, "ReentrantMutex {{ data: Poisoned({:?}) }}", &**err.get_ref())
+                f.debug_struct("ReentrantMutex").field("data", &**err.get_ref()).finish()
             },
-            Err(TryLockError::WouldBlock) => write!(f, "ReentrantMutex {{ <locked> }}")
+            Err(TryLockError::WouldBlock) => {
+                struct LockedPlaceholder;
+                impl fmt::Debug for LockedPlaceholder {
+                    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { f.write_str("<locked>") }
+                }
+
+                f.debug_struct("ReentrantMutex").field("data", &LockedPlaceholder).finish()
+            }
         }
     }
 }
diff --git a/src/libstd/sys_common/thread.rs b/src/libstd/sys_common/thread.rs
index 87fb34a9dec..f1379b6ec63 100644
--- a/src/libstd/sys_common/thread.rs
+++ b/src/libstd/sys_common/thread.rs
@@ -8,14 +8,14 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use env;
 use alloc::boxed::FnBox;
-use libc;
+use env;
 use sync::atomic::{self, Ordering};
 use sys::stack_overflow;
 use sys::thread as imp;
 
-pub unsafe fn start_thread(main: *mut libc::c_void) {
+#[allow(dead_code)]
+pub unsafe fn start_thread(main: *mut u8) {
     // Next, set up our stack overflow handler which may get triggered if we run
     // out of stack.
     let _handler = stack_overflow::Handler::new();
diff --git a/src/libstd/sys_common/thread_local.rs b/src/libstd/sys_common/thread_local.rs
index 87ffd304e1a..a4aa3d96d25 100644
--- a/src/libstd/sys_common/thread_local.rs
+++ b/src/libstd/sys_common/thread_local.rs
@@ -262,7 +262,7 @@ pub unsafe fn register_dtor_fallback(t: *mut u8,
     unsafe extern fn run_dtors(mut ptr: *mut u8) {
         while !ptr.is_null() {
             let list: Box<List> = Box::from_raw(ptr as *mut List);
-            for &(ptr, dtor) in list.iter() {
+            for (ptr, dtor) in list.into_iter() {
                 dtor(ptr);
             }
             ptr = DTORS.get();
diff --git a/src/libstd/sys_common/wtf8.rs b/src/libstd/sys_common/wtf8.rs
index b89a73cd28a..e212b5006f2 100644
--- a/src/libstd/sys_common/wtf8.rs
+++ b/src/libstd/sys_common/wtf8.rs
@@ -35,8 +35,10 @@ use hash::{Hash, Hasher};
 use iter::FromIterator;
 use mem;
 use ops;
+use rc::Rc;
 use slice;
 use str;
+use sync::Arc;
 use sys_common::AsInner;
 
 const UTF8_REPLACEMENT_CHARACTER: &'static str = "\u{FFFD}";
@@ -641,6 +643,18 @@ impl Wtf8 {
         let boxed: Box<[u8]> = Default::default();
         unsafe { mem::transmute(boxed) }
     }
+
+    #[inline]
+    pub fn into_arc(&self) -> Arc<Wtf8> {
+        let arc: Arc<[u8]> = Arc::from(&self.bytes);
+        unsafe { Arc::from_raw(Arc::into_raw(arc) as *const Wtf8) }
+    }
+
+    #[inline]
+    pub fn into_rc(&self) -> Rc<Wtf8> {
+        let rc: Rc<[u8]> = Rc::from(&self.bytes);
+        unsafe { Rc::from_raw(Rc::into_raw(rc) as *const Wtf8) }
+    }
 }