diff --git a/src/test/run-pass/issue-13304.rs b/src/test/run-pass/issue-13304.rs
index 1676281aa2fb5..36036ae241e21 100644
--- a/src/test/run-pass/issue-13304.rs
+++ b/src/test/run-pass/issue-13304.rs
@@ -11,8 +11,6 @@
 // ignore-cloudabi no processes
 // ignore-emscripten no processes
 
-#![feature(io)]
-
 use std::env;
 use std::io::prelude::*;
 use std::io;
diff --git a/src/test/run-pass/issue-14456.rs b/src/test/run-pass/issue-14456.rs
index bfedc52919c09..601fafbf02eb9 100644
--- a/src/test/run-pass/issue-14456.rs
+++ b/src/test/run-pass/issue-14456.rs
@@ -11,8 +11,6 @@
 // ignore-cloudabi no processes
 // ignore-emscripten no processes
 
-#![feature(io)]
-
 use std::env;
 use std::io::prelude::*;
 use std::io;
diff --git a/src/test/run-pass/issue-17322.rs b/src/test/run-pass/issue-17322.rs
index 47dfe878c26dc..c94345f794d17 100644
--- a/src/test/run-pass/issue-17322.rs
+++ b/src/test/run-pass/issue-17322.rs
@@ -10,7 +10,7 @@
 
 // pretty-expanded FIXME #23616
 
-#![feature(box_syntax, io)]
+#![feature(box_syntax)]
 
 use std::io::{self, Write};
 
diff --git a/src/test/run-pass/issue-4333.rs b/src/test/run-pass/issue-4333.rs
index 48753e15a705d..a84d7f3fe8287 100644
--- a/src/test/run-pass/issue-4333.rs
+++ b/src/test/run-pass/issue-4333.rs
@@ -10,8 +10,6 @@
 
 // pretty-expanded FIXME #23616
 
-#![feature(io)]
-
 use std::io;
 
 pub fn main() {