9 files changed, 13 insertions, 8 deletions
diff --git a/src/libstd/sync/barrier.rs b/src/libstd/sync/barrier.rs
index ac0f400379e..f46eab68484 100644
--- a/src/libstd/sync/barrier.rs
+++ b/src/libstd/sync/barrier.rs
@@ -118,6 +118,7 @@ mod tests {
     use thread;
 
     #[test]
+    #[cfg_attr(target_os = "emscripten", ignore)]
     fn test_barrier() {
         const N: usize = 10;
 
diff --git a/src/libstd/sync/condvar.rs b/src/libstd/sync/condvar.rs
index 3db8b05b954..a983ae716a4 100644
--- a/src/libstd/sync/condvar.rs
+++ b/src/libstd/sync/condvar.rs
@@ -270,6 +270,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg_attr(target_os = "emscripten", ignore)]
     fn notify_one() {
         let m = Arc::new(Mutex::new(()));
         let m2 = m.clone();
@@ -286,6 +287,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg_attr(target_os = "emscripten", ignore)]
     fn notify_all() {
         const N: usize = 10;
 
@@ -322,6 +324,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg_attr(target_os = "emscripten", ignore)]
     fn wait_timeout_ms() {
         let m = Arc::new(Mutex::new(()));
         let m2 = m.clone();
@@ -343,6 +346,7 @@ mod tests {
 
     #[test]
     #[should_panic]
+    #[cfg_attr(target_os = "emscripten", ignore)]
     fn two_mutexes() {
         let m = Arc::new(Mutex::new(()));
         let m2 = m.clone();
diff --git a/src/libstd/sync/mpsc/mod.rs b/src/libstd/sync/mpsc/mod.rs
index 3d9f81413dc..d9c14ef2f77 100644
--- a/src/libstd/sync/mpsc/mod.rs
+++ b/src/libstd/sync/mpsc/mod.rs
@@ -1268,7 +1268,7 @@ impl error::Error for TryRecvError {
     }
 }
 
-#[cfg(test)]
+#[cfg(all(test, not(target_os = "emscripten")))]
 mod tests {
     use env;
     use super::*;
@@ -1942,7 +1942,7 @@ mod tests {
     }
 }
 
-#[cfg(test)]
+#[cfg(all(test, not(target_os = "emscripten")))]
 mod sync_tests {
     use env;
     use thread;
diff --git a/src/libstd/sync/mpsc/mpsc_queue.rs b/src/libstd/sync/mpsc/mpsc_queue.rs
index d926043fbbc..8d80f942ff7 100644
--- a/src/libstd/sync/mpsc/mpsc_queue.rs
+++ b/src/libstd/sync/mpsc/mpsc_queue.rs
@@ -146,7 +146,7 @@ impl<T> Drop for Queue<T> {
     }
 }
 
-#[cfg(test)]
+#[cfg(all(test, not(target_os = "emscripten")))]
 mod tests {
     use sync::mpsc::channel;
     use super::{Queue, Data, Empty, Inconsistent};
diff --git a/src/libstd/sync/mpsc/select.rs b/src/libstd/sync/mpsc/select.rs
index 51b08bd75c4..91896e1ab85 100644
--- a/src/libstd/sync/mpsc/select.rs
+++ b/src/libstd/sync/mpsc/select.rs
@@ -366,7 +366,7 @@ impl<'rx, T:Send+'rx> fmt::Debug for Handle<'rx, T> {
     }
 }
 
-#[cfg(test)]
+#[cfg(all(test, not(target_os = "emscripten")))]
 #[allow(unused_imports)]
 mod tests {
     use thread;
diff --git a/src/libstd/sync/mpsc/spsc_queue.rs b/src/libstd/sync/mpsc/spsc_queue.rs
index 724d7b1be73..5858e4b6ddb 100644
--- a/src/libstd/sync/mpsc/spsc_queue.rs
+++ b/src/libstd/sync/mpsc/spsc_queue.rs
@@ -231,7 +231,7 @@ impl<T> Drop for Queue<T> {
     }
 }
 
-#[cfg(test)]
+#[cfg(all(test, not(target_os = "emscripten")))]
 mod tests {
     use sync::Arc;
     use super::Queue;
diff --git a/src/libstd/sync/mutex.rs b/src/libstd/sync/mutex.rs
index 098a3e44258..812724c7a16 100644
--- a/src/libstd/sync/mutex.rs
+++ b/src/libstd/sync/mutex.rs
@@ -352,7 +352,7 @@ pub fn guard_poison<'a, T: ?Sized>(guard: &MutexGuard<'a, T>) -> &'a poison::Fla
     &guard.__lock.poison
 }
 
-#[cfg(test)]
+#[cfg(all(test, not(target_os = "emscripten")))]
 mod tests {
     use sync::mpsc::channel;
     use sync::{Arc, Mutex, Condvar};
diff --git a/src/libstd/sync/once.rs b/src/libstd/sync/once.rs
index 86d2986959c..ad9d0b37544 100644
--- a/src/libstd/sync/once.rs
+++ b/src/libstd/sync/once.rs
@@ -367,7 +367,7 @@ impl OnceState {
     }
 }
 
-#[cfg(test)]
+#[cfg(all(test, not(target_os = "emscripten")))]
 mod tests {
     use panic;
     use sync::mpsc::channel;
diff --git a/src/libstd/sync/rwlock.rs b/src/libstd/sync/rwlock.rs
index 7f053c6704b..48ecae185f9 100644
--- a/src/libstd/sync/rwlock.rs
+++ b/src/libstd/sync/rwlock.rs
@@ -380,7 +380,7 @@ impl<'a, T: ?Sized> Drop for RwLockWriteGuard<'a, T> {
     }
 }
 
-#[cfg(test)]
+#[cfg(all(test, not(target_os = "emscripten")))]
 mod tests {
     #![allow(deprecated)] // rand