Auto merge of #21439 - alexcrichton:rollup, r=alexcrichton

Continuation of https://github.com/rust-lang/rust/pull/21428

1 files changed, 3 insertions, 3 deletions

diff --git a/src/libstd/os.rs b/src/libstd/os.rs
index fc0c838a3f1..78db6c158a8 100644
--- a/src/libstd/os.rs
+++ b/src/libstd/os.rs
@@ -37,7 +37,7 @@ use error::{FromError, Error};
 use fmt;
 use io::{IoResult, IoError};
 use iter::{Iterator, IteratorExt};
-use marker::Copy;
+use marker::{Copy, Send};
 use libc::{c_void, c_int, c_char};
 use libc;
 use boxed::Box;
@@ -937,8 +937,8 @@ impl Error for MapError {
     fn detail(&self) -> Option<String> { Some(format!("{:?}", self)) }
 }
 
-impl FromError<MapError> for Box<Error> {
-    fn from_error(err: MapError) -> Box<Error> {
+impl FromError<MapError> for Box<Error + Send> {
+    fn from_error(err: MapError) -> Box<Error + Send> {
         box err
     }
 }