Auto merge of #11841 - asajeffrey:constellation-logging, r=Manishearth

Send log messages to the constellation

<!-- Please describe your changes on the following line: -->

Send all warnings and errors to the constellation. Warnings are bufferred up, and included in any subsequent error reports. Errors are reported in the same way as panics.

Note that this can't merge yet, as it needs https://github.com/rust-lang-nursery/log/pull/86 to land.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #11776 (github issue number if applicable).
- [X] These changes do not require tests because we don't test crash reporting.

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

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11 files changed, 229 insertions, 18 deletions

diff --git a/components/constellation/Cargo.toml b/components/constellation/Cargo.toml
index bb6548d1e64..f2cf43340de 100644
--- a/components/constellation/Cargo.toml
+++ b/components/constellation/Cargo.toml
@@ -10,6 +10,7 @@ name = "constellation"
 path = "lib.rs"
 
 [dependencies]
+backtrace = "0.2.1"
 canvas = {path = "../canvas"}
 canvas_traits = {path = "../canvas_traits"}
 clipboard = {git = "https://github.com/aweinstock314/rust-clipboard"}
diff --git a/components/constellation/constellation.rs b/components/constellation/constellation.rs
index 699b77ba1f1..b262684d5d9 100644
--- a/components/constellation/constellation.rs
+++ b/components/constellation/constellation.rs
@@ -9,6 +9,7 @@
 //! navigation context, each `Pipeline` encompassing a `ScriptThread`,
 //! `LayoutThread`, and `PaintThread`.
 
+use backtrace::Backtrace;
 use canvas::canvas_paint_thread::CanvasPaintThread;
 use canvas::webgl_paint_thread::WebGLPaintThread;
 use canvas_traits::CanvasMsg;
@@ -24,6 +25,7 @@ use gfx_traits::Epoch;
 use ipc_channel::ipc::{self, IpcSender};
 use ipc_channel::router::ROUTER;
 use layout_traits::LayoutThreadFactory;
+use log::{Log, LogLevel, LogLevelFilter, LogMetadata, LogRecord};
 use msg::constellation_msg::{FrameId, FrameType, PipelineId};
 use msg::constellation_msg::{Key, KeyModifiers, KeyState, LoadData};
 use msg::constellation_msg::{PipelineNamespace, PipelineNamespaceId, NavigationDirection};
@@ -45,14 +47,16 @@ use script_traits::{ConstellationControlMsg, ConstellationMsg as FromCompositorM
 use script_traits::{DocumentState, LayoutControlMsg};
 use script_traits::{IFrameLoadInfo, IFrameSandboxState, TimerEventRequest};
 use script_traits::{LayoutMsg as FromLayoutMsg, ScriptMsg as FromScriptMsg, ScriptThreadFactory};
-use script_traits::{MozBrowserEvent, MozBrowserErrorType, WebDriverCommandMsg, WindowSizeData};
+use script_traits::{LogEntry, MozBrowserEvent, MozBrowserErrorType, WebDriverCommandMsg, WindowSizeData};
 use std::borrow::ToOwned;
-use std::collections::HashMap;
+use std::collections::{HashMap, VecDeque};
 use std::io::Error as IOError;
 use std::marker::PhantomData;
 use std::mem::replace;
 use std::process;
 use std::sync::mpsc::{Sender, channel, Receiver};
+use std::sync::{Arc, Mutex};
+use std::thread;
 use style_traits::PagePx;
 use style_traits::cursor::Cursor;
 use style_traits::viewport::ViewportConstraints;
@@ -182,6 +186,10 @@ pub struct Constellation<Message, LTF, STF> {
     /// Have we seen any panics? Hopefully always false!
     handled_panic: bool,
 
+    /// Have we seen any warnings? Hopefully always empty!
+    /// The buffer contains `(thread_name, reason)` entries.
+    handled_warnings: VecDeque<(Option<String>, String)>,
+
     /// The random number generator and probability for closing pipelines.
     /// This is for testing the hardening of the constellation.
     random_pipeline_closure: Option<(StdRng, f32)>,
@@ -304,6 +312,100 @@ enum ExitPipelineMode {
     Force,
 }
 
+/// A logger directed at the constellation from content processes
+#[derive(Clone)]
+pub struct FromScriptLogger {
+    /// A channel to the constellation
+    pub constellation_chan: Arc<Mutex<IpcSender<FromScriptMsg>>>,
+}
+
+impl FromScriptLogger {
+    /// Create a new constellation logger.
+    pub fn new(constellation_chan: IpcSender<FromScriptMsg>) -> FromScriptLogger {
+        FromScriptLogger {
+            constellation_chan: Arc::new(Mutex::new(constellation_chan))
+        }
+    }
+
+    /// The maximum log level the constellation logger is interested in.
+    pub fn filter(&self) -> LogLevelFilter {
+        LogLevelFilter::Warn
+    }
+}
+
+impl Log for FromScriptLogger {
+    fn enabled(&self, metadata: &LogMetadata) -> bool {
+        metadata.level() <= LogLevel::Warn
+    }
+
+    fn log(&self, record: &LogRecord) {
+        if let Some(entry) = log_entry(record) {
+            // TODO: Store the pipeline id in TLS so we can recover it here
+            let thread_name = thread::current().name().map(ToOwned::to_owned);
+            let msg = FromScriptMsg::LogEntry(None, thread_name, entry);
+            if let Ok(chan) = self.constellation_chan.lock() {
+                let _ = chan.send(msg);
+            }
+        }
+    }
+}
+
+/// A logger directed at the constellation from the compositor
+#[derive(Clone)]
+pub struct FromCompositorLogger {
+    /// A channel to the constellation
+    pub constellation_chan: Arc<Mutex<Sender<FromCompositorMsg>>>,
+}
+
+impl FromCompositorLogger {
+    /// Create a new constellation logger.
+    pub fn new(constellation_chan: Sender<FromCompositorMsg>) -> FromCompositorLogger {
+        FromCompositorLogger {
+            constellation_chan: Arc::new(Mutex::new(constellation_chan))
+        }
+    }
+
+    /// The maximum log level the constellation logger is interested in.
+    pub fn filter(&self) -> LogLevelFilter {
+        LogLevelFilter::Warn
+    }
+}
+
+impl Log for FromCompositorLogger {
+    fn enabled(&self, metadata: &LogMetadata) -> bool {
+        metadata.level() <= LogLevel::Warn
+    }
+
+    fn log(&self, record: &LogRecord) {
+        if let Some(entry) = log_entry(record) {
+            // TODO: Store the pipeline id in TLS so we can recover it here
+            let thread_name = thread::current().name().map(ToOwned::to_owned);
+            let msg = FromCompositorMsg::LogEntry(None, thread_name, entry);
+            if let Ok(chan) = self.constellation_chan.lock() {
+                let _ = chan.send(msg);
+            }
+        }
+    }
+}
+
+fn log_entry(record: &LogRecord) -> Option<LogEntry> {
+    match record.level() {
+        LogLevel::Error if thread::panicking() => Some(LogEntry::Panic(
+            format!("{}", record.args()),
+            format!("{:?}", Backtrace::new())
+        )),
+        LogLevel::Error => Some(LogEntry::Error(
+            format!("{}", record.args())
+        )),
+        LogLevel::Warn => Some(LogEntry::Warn(
+            format!("{}", record.args())
+        )),
+        _ => None,
+    }
+}
+
+const WARNINGS_BUFFER_SIZE: usize = 32;
+
 impl<Message, LTF, STF> Constellation<Message, LTF, STF>
     where LTF: LayoutThreadFactory<Message=Message>,
           STF: ScriptThreadFactory<Message=Message>
@@ -367,6 +469,7 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
                 webrender_api_sender: state.webrender_api_sender,
                 shutting_down: false,
                 handled_panic: false,
+                handled_warnings: VecDeque::new(),
                 random_pipeline_closure: opts::get().random_pipeline_closure_probability.map(|prob| {
                     let seed = opts::get().random_pipeline_closure_seed.unwrap_or_else(random);
                     let rng = StdRng::from_seed(&[seed]);
@@ -621,6 +724,9 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
                 debug!("constellation got reload message");
                 self.handle_reload_msg();
             }
+            FromCompositorMsg::LogEntry(pipeline_id, thread_name, entry) => {
+                self.handle_log_entry(pipeline_id, thread_name, entry);
+            }
         }
     }
 
@@ -798,6 +904,9 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
             FromScriptMsg::Exit => {
                 self.compositor_proxy.send(ToCompositorMsg::Exit);
             }
+            FromScriptMsg::LogEntry(pipeline_id, thread_name, entry) => {
+                self.handle_log_entry(pipeline_id, thread_name, entry);
+            }
 
             FromScriptMsg::SetTitle(pipeline_id, title) => {
                 self.compositor_proxy.send(ToCompositorMsg::ChangePageTitle(pipeline_id, title))
@@ -973,6 +1082,21 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
         self.handled_panic = true;
     }
 
+    // TODO: trigger a mozbrowsererror even if there's no pipeline id
+    fn handle_log_entry(&mut self, pipeline_id: Option<PipelineId>, thread_name: Option<String>, entry: LogEntry) {
+        match (pipeline_id, entry) {
+            (Some(pipeline_id), LogEntry::Panic(reason, backtrace)) =>
+                self.trigger_mozbrowsererror(pipeline_id, reason, backtrace),
+            (None, LogEntry::Panic(reason, _)) | (_, LogEntry::Error(reason)) | (_, LogEntry::Warn(reason)) => {
+                // VecDeque::truncate is unstable
+                if WARNINGS_BUFFER_SIZE <= self.handled_warnings.len() {
+                    self.handled_warnings.pop_front();
+                }
+                self.handled_warnings.push_back((thread_name, reason));
+            },
+        }
+    }
+
     fn handle_init_load(&mut self, url: Url) {
         let window_size = self.window_size.visible_viewport;
         let root_pipeline_id = PipelineId::new();
@@ -2050,7 +2174,7 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
                     } else {
                         // Note that we deliberately do not do any of the tidying up
                         // associated with closing a pipeline. The constellation should cope!
-                        info!("Randomly closing pipeline {}.", pipeline_id);
+                        warn!("Randomly closing pipeline {}.", pipeline_id);
                         pipeline.force_exit();
                     }
                 }
@@ -2156,7 +2280,8 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
 
     // https://developer.mozilla.org/en-US/docs/Web/Events/mozbrowsererror
     // Note that this does not require the pipeline to be an immediate child of the root
-    fn trigger_mozbrowsererror(&self, pipeline_id: PipelineId, reason: String, backtrace: String) {
+    // TODO: allow the pipeline id to be optional, triggering the error on the root if it's not provided.
+    fn trigger_mozbrowsererror(&mut self, pipeline_id: PipelineId, reason: String, backtrace: String) {
         if !PREFS.is_mozbrowser_enabled() { return; }
 
         let ancestor_info = self.get_mozbrowser_ancestor_info(pipeline_id);
@@ -2164,7 +2289,21 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
         if let Some(ancestor_info) = ancestor_info {
             match self.pipelines.get(&ancestor_info.0) {
                 Some(ancestor) => {
-                    let event = MozBrowserEvent::Error(MozBrowserErrorType::Fatal, Some(reason), Some(backtrace));
+                    let mut report = String::new();
+                    for (thread_name, warning) in self.handled_warnings.drain(..) {
+                        report.push_str("\nWARNING: ");
+                        if let Some(thread_name) = thread_name {
+                            report.push_str("<");
+                            report.push_str(&*thread_name);
+                            report.push_str(">: ");
+                        }
+                        report.push_str(&*warning);
+                    }
+                    report.push_str("\nERROR: ");
+                    report.push_str(&*reason);
+                    report.push_str("\n\n");
+                    report.push_str(&*backtrace);
+                    let event = MozBrowserEvent::Error(MozBrowserErrorType::Fatal, Some(reason), Some(report));
                     ancestor.trigger_mozbrowser_event(ancestor_info.1, event);
                 },
                 None => return warn!("Mozbrowsererror via closed pipeline {:?}.", ancestor_info.0),
diff --git a/components/constellation/lib.rs b/components/constellation/lib.rs
index 57a715abfa6..aeeeae8a1d2 100644
--- a/components/constellation/lib.rs
+++ b/components/constellation/lib.rs
@@ -12,6 +12,7 @@
 #![deny(unsafe_code)]
 #![plugin(serde_macros)]
 
+extern crate backtrace;
 extern crate canvas;
 extern crate canvas_traits;
 extern crate clipboard;
@@ -47,7 +48,7 @@ mod pipeline;
 mod sandboxing;
 mod timer_scheduler;
 
-pub use constellation::{Constellation, InitialConstellationState};
+pub use constellation::{Constellation, FromCompositorLogger, FromScriptLogger, InitialConstellationState};
 pub use pipeline::UnprivilegedPipelineContent;
 #[cfg(not(target_os = "windows"))]
 pub use sandboxing::content_process_sandbox_profile;
diff --git a/components/constellation/pipeline.rs b/components/constellation/pipeline.rs
index bd9988364a2..c07891984ed 100644
--- a/components/constellation/pipeline.rs
+++ b/components/constellation/pipeline.rs
@@ -535,6 +535,10 @@ impl UnprivilegedPipelineContent {
         process::exit(1);
     }
 
+    pub fn constellation_chan(&self) -> IpcSender<ScriptMsg> {
+        self.constellation_chan.clone()
+    }
+
     pub fn opts(&self) -> Opts {
         self.opts.clone()
     }
diff --git a/components/script_traits/lib.rs b/components/script_traits/lib.rs
index ab1a7d7ee52..967303e63b8 100644
--- a/components/script_traits/lib.rs
+++ b/components/script_traits/lib.rs
@@ -66,7 +66,7 @@ use url::Url;
 use util::ipc::OptionalOpaqueIpcSender;
 use webdriver_msg::{LoadStatus, WebDriverScriptCommand};
 
-pub use script_msg::{LayoutMsg, ScriptMsg, EventResult};
+pub use script_msg::{LayoutMsg, ScriptMsg, EventResult, LogEntry};
 
 /// The address of a node. Layout sends these back. They must be validated via
 /// `from_untrusted_node_address` before they can be used, because we do not trust layout.
@@ -436,6 +436,7 @@ pub enum MozBrowserEvent {
     /// handling `<menuitem>` element available within the browser `<iframe>`'s content.
     ContextMenu,
     /// Sent when an error occurred while trying to load content within a browser `<iframe>`.
+    /// Includes an optional human-readable description, and an optional machine-readable report.
     Error(MozBrowserErrorType, Option<String>, Option<String>),
     /// Sent when the favicon of a browser `<iframe>` changes.
     IconChange(String, String, String),
@@ -599,4 +600,6 @@ pub enum ConstellationMsg {
     WebDriverCommand(WebDriverCommandMsg),
     /// Reload the current page.
     Reload,
+    /// A log entry, with the pipeline id and thread name
+    LogEntry(Option<PipelineId>, Option<String>, LogEntry),
 }
diff --git a/components/script_traits/script_msg.rs b/components/script_traits/script_msg.rs
index 0ac5aeae4b4..e510a74a9c1 100644
--- a/components/script_traits/script_msg.rs
+++ b/components/script_traits/script_msg.rs
@@ -40,6 +40,19 @@ pub enum EventResult {
     DefaultPrevented,
 }
 
+/// A log entry reported to the constellation
+/// We don't report all log entries, just serious ones.
+/// We need a separate type for this because LogLevel isn't serializable.
+#[derive(Clone, Debug, Deserialize, Serialize)]
+pub enum LogEntry {
+    /// Panic, with a reason and backtrace
+    Panic(String, String),
+    /// Error, with a reason
+    Error(String),
+    /// warning, with a reason
+    Warn(String)
+}
+
 /// Messages from the script to the constellation.
 #[derive(Deserialize, Serialize)]
 pub enum ScriptMsg {
@@ -114,6 +127,8 @@ pub enum ScriptMsg {
     TouchEventProcessed(EventResult),
     /// Get Scroll Offset
     GetScrollOffset(PipelineId, LayerId, IpcSender<Point2D<f32>>),
+    /// A log entry, with the pipeline id and thread name
+    LogEntry(Option<PipelineId>, Option<String>, LogEntry),
     /// Notifies the constellation that this pipeline has exited.
     PipelineExited(PipelineId),
     /// Requests that the compositor shut down.
diff --git a/components/servo/Cargo.lock b/components/servo/Cargo.lock
index fffb80f04ea..da1d71b5544 100644
--- a/components/servo/Cargo.lock
+++ b/components/servo/Cargo.lock
@@ -12,7 +12,7 @@ dependencies = [
  "constellation 0.0.1",
  "devtools 0.0.1",
  "devtools_traits 0.0.1",
- "env_logger 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "env_logger 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gaol 0.0.1 (git+https://github.com/servo/gaol)",
  "gfx 0.0.1",
@@ -357,6 +357,7 @@ dependencies = [
 name = "constellation"
 version = "0.0.1"
 dependencies = [
+ "backtrace 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "canvas 0.0.1",
  "canvas_traits 0.0.1",
  "clipboard 0.1.2 (git+https://github.com/aweinstock314/rust-clipboard)",
@@ -670,7 +671,7 @@ dependencies = [
 
 [[package]]
 name = "env_logger"
-version = "0.3.3"
+version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/components/servo/lib.rs b/components/servo/lib.rs
index 8ef09eb066e..20aee632c1d 100644
--- a/components/servo/lib.rs
+++ b/components/servo/lib.rs
@@ -17,10 +17,12 @@
 //! The `Browser` is fed events from a generic type that implements the
 //! `WindowMethods` trait.
 
+extern crate env_logger;
 #[cfg(not(target_os = "windows"))]
 extern crate gaol;
 #[macro_use]
 extern crate gleam;
+extern crate log;
 
 pub extern crate canvas;
 pub extern crate canvas_traits;
@@ -65,10 +67,13 @@ use compositing::{CompositorProxy, IOCompositor};
 #[cfg(not(target_os = "windows"))]
 use constellation::content_process_sandbox_profile;
 use constellation::{Constellation, InitialConstellationState, UnprivilegedPipelineContent};
+use constellation::{FromScriptLogger, FromCompositorLogger};
+use env_logger::Logger as EnvLogger;
 #[cfg(not(target_os = "windows"))]
 use gaol::sandbox::{ChildSandbox, ChildSandboxMethods};
 use gfx::font_cache_thread::FontCacheThread;
 use ipc_channel::ipc::{self, IpcSender};
+use log::{Log, LogMetadata, LogRecord};
 use net::bluetooth_thread::BluetoothThreadFactory;
 use net::image_cache_thread::new_image_cache_thread;
 use net::resource_thread::new_resource_threads;
@@ -78,7 +83,8 @@ use profile::mem as profile_mem;
 use profile::time as profile_time;
 use profile_traits::mem;
 use profile_traits::time;
-use script_traits::ConstellationMsg;
+use script_traits::{ConstellationMsg, ScriptMsg};
+use std::cmp::max;
 use std::rc::Rc;
 use std::sync::mpsc::Sender;
 use util::opts;
@@ -100,6 +106,7 @@ pub use gleam::gl;
 /// various browser components.
 pub struct Browser<Window: WindowMethods + 'static> {
     compositor: IOCompositor<Window>,
+    constellation_chan: Sender<ConstellationMsg>,
 }
 
 impl<Window> Browser<Window> where Window: WindowMethods + 'static {
@@ -172,7 +179,7 @@ impl<Window> Browser<Window> where Window: WindowMethods + 'static {
         let compositor = IOCompositor::create(window, InitialCompositorState {
             sender: compositor_proxy,
             receiver: compositor_receiver,
-            constellation_chan: constellation_chan,
+            constellation_chan: constellation_chan.clone(),
             time_profiler_chan: time_profiler_chan,
             mem_profiler_chan: mem_profiler_chan,
             webrender: webrender,
@@ -181,6 +188,7 @@ impl<Window> Browser<Window> where Window: WindowMethods + 'static {
 
         Browser {
             compositor: compositor,
+            constellation_chan: constellation_chan,
         }
     }
 
@@ -199,6 +207,18 @@ impl<Window> Browser<Window> where Window: WindowMethods + 'static {
     pub fn request_title_for_main_frame(&self) {
         self.compositor.title_for_main_frame()
     }
+
+    pub fn setup_logging(&self) {
+        let constellation_chan = self.constellation_chan.clone();
+        log::set_logger(|max_log_level| {
+            let env_logger = EnvLogger::new();
+            let con_logger = FromCompositorLogger::new(constellation_chan);
+            let filter = max(env_logger.filter(), con_logger.filter());
+            let logger = BothLogger(env_logger, con_logger);
+            max_log_level.set(filter);
+            Box::new(logger)
+        }).expect("Failed to set logger.")
+    }
 }
 
 fn create_constellation(opts: opts::Opts,
@@ -244,6 +264,32 @@ fn create_constellation(opts: opts::Opts,
     constellation_chan
 }
 
+// A logger that logs to two downstream loggers.
+// This should probably be in the log crate.
+struct BothLogger<Log1, Log2>(Log1, Log2);
+
+impl<Log1, Log2> Log for BothLogger<Log1, Log2> where Log1: Log, Log2: Log {
+    fn enabled(&self, metadata: &LogMetadata) -> bool {
+        self.0.enabled(metadata) || self.1.enabled(metadata)
+    }
+
+    fn log(&self, record: &LogRecord) {
+        self.0.log(record);
+        self.1.log(record);
+    }
+}
+
+pub fn set_logger(constellation_chan: IpcSender<ScriptMsg>) {
+    log::set_logger(|max_log_level| {
+        let env_logger = EnvLogger::new();
+        let con_logger = FromScriptLogger::new(constellation_chan);
+        let filter = max(env_logger.filter(), con_logger.filter());
+        let logger = BothLogger(env_logger, con_logger);
+        max_log_level.set(filter);
+        Box::new(logger)
+    }).expect("Failed to set logger.")
+}
+
 /// Content process entry point.
 pub fn run_content_process(token: String) {
     let (unprivileged_content_sender, unprivileged_content_receiver) =
@@ -255,6 +301,7 @@ pub fn run_content_process(token: String) {
     let unprivileged_content = unprivileged_content_receiver.recv().unwrap();
     opts::set_defaults(unprivileged_content.opts());
     PREFS.extend(unprivileged_content.prefs());
+    set_logger(unprivileged_content.constellation_chan());
 
     // Enter the sandbox if necessary.
     if opts::get().sandbox {
diff --git a/components/servo/main.rs b/components/servo/main.rs
index 66f5a149158..954c3f0e848 100644
--- a/components/servo/main.rs
+++ b/components/servo/main.rs
@@ -22,7 +22,6 @@
 extern crate android_glue;
 #[cfg(not(target_os = "android"))]
 extern crate backtrace;
-extern crate env_logger;
 // The window backed by glutin
 extern crate glutin_app as app;
 #[cfg(target_os = "android")]
@@ -96,8 +95,6 @@ fn main() {
     };
 
     initiate_panic_hook();
-    env_logger::init().unwrap();
-
     setup_logging();
 
     if let Some(token) = content_process_token {
@@ -117,6 +114,8 @@ fn main() {
         browser: Browser::new(window.clone()),
     };
 
+    browser.browser.setup_logging();
+
     register_glutin_resize_handler(&window, &mut browser);
 
     browser.browser.handle_events(vec![WindowEvent::InitializeCompositing]);
diff --git a/ports/cef/Cargo.lock b/ports/cef/Cargo.lock
index 3aeab203fa8..dc270a4081f 100644
--- a/ports/cef/Cargo.lock
+++ b/ports/cef/Cargo.lock
@@ -316,6 +316,7 @@ dependencies = [
 name = "constellation"
 version = "0.0.1"
 dependencies = [
+ "backtrace 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "canvas 0.0.1",
  "canvas_traits 0.0.1",
  "clipboard 0.1.2 (git+https://github.com/aweinstock314/rust-clipboard)",
@@ -588,7 +589,7 @@ dependencies = [
 
 [[package]]
 name = "env_logger"
-version = "0.3.3"
+version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1939,7 +1940,7 @@ dependencies = [
  "constellation 0.0.1",
  "devtools 0.0.1",
  "devtools_traits 0.0.1",
- "env_logger 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "env_logger 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gaol 0.0.1 (git+https://github.com/servo/gaol)",
  "gfx 0.0.1",
diff --git a/ports/geckolib/Cargo.lock b/ports/geckolib/Cargo.lock
index 9f1b54a59eb..58c8f5d50d5 100644
--- a/ports/geckolib/Cargo.lock
+++ b/ports/geckolib/Cargo.lock
@@ -4,7 +4,7 @@ version = "0.0.1"
 dependencies = [
  "app_units 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "cssparser 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "env_logger 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "env_logger 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gecko_bindings 0.0.1",
  "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -124,7 +124,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "env_logger"
-version = "0.3.3"
+version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",