diff --git a/src/librustc/lib.rs b/src/librustc/lib.rs
index dc26140ace5..63e0107a4d8 100644
--- a/src/librustc/lib.rs
+++ b/src/librustc/lib.rs
@@ -49,7 +49,6 @@
 #![feature(optin_builtin_traits)]
 #![feature(range_is_empty)]
 #![feature(rustc_diagnostic_macros)]
-#![feature(rustc_attrs)]
 #![feature(slice_patterns)]
 #![feature(specialization)]
 #![feature(unboxed_closures)]
@@ -57,7 +56,6 @@
 #![feature(trace_macros)]
 #![feature(trusted_len)]
 #![feature(vec_remove_item)]
-#![feature(step_trait)]
 #![feature(stmt_expr_attributes)]
 #![feature(integer_atomics)]
 #![feature(test)]
diff --git a/src/librustc_data_structures/indexed_vec.rs b/src/librustc_data_structures/indexed_vec.rs
index b3a810a622d..c3c76e81606 100644
--- a/src/librustc_data_structures/indexed_vec.rs
+++ b/src/librustc_data_structures/indexed_vec.rs
@@ -57,12 +57,13 @@ impl Idx for u32 {
 /// `u32::MAX`. You can also customize things like the `Debug` impl,
 /// what traits are derived, and so forth via the macro.
 #[macro_export]
+#[allow_internal_unstable(step_trait, rustc_attrs)]
 macro_rules! newtype_index {
     // ---- public rules ----
 
     // Use default constants
     ($(#[$attrs:meta])* $v:vis struct $name:ident { .. }) => (
-        newtype_index!(
+        $crate::newtype_index!(
             // Leave out derives marker so we can use its absence to ensure it comes first
             @attrs        [$(#[$attrs])*]
             @type         [$name]
@@ -74,7 +75,7 @@ macro_rules! newtype_index {
 
     // Define any constants
     ($(#[$attrs:meta])* $v:vis struct $name:ident { $($tokens:tt)+ }) => (
-        newtype_index!(
+        $crate::newtype_index!(
             // Leave out derives marker so we can use its absence to ensure it comes first
             @attrs        [$(#[$attrs])*]
             @type         [$name]
@@ -258,7 +259,7 @@ macro_rules! newtype_index {
             }
         }
 
-        newtype_index!(
+        $crate::newtype_index!(
             @handle_debug
             @derives      [$($derives,)*]
             @type         [$type]
@@ -294,7 +295,7 @@ macro_rules! newtype_index {
      @derives      [$_derive:ident, $($derives:ident,)*]
      @type         [$type:ident]
      @debug_format [$debug_format:tt]) => (
-        newtype_index!(
+        $crate::newtype_index!(
             @handle_debug
             @derives      [$($derives,)*]
             @type         [$type]
@@ -309,7 +310,7 @@ macro_rules! newtype_index {
      @debug_format [$debug_format:tt]
                    derive [$($derives:ident),*]
                    $($tokens:tt)*) => (
-        newtype_index!(
+        $crate::newtype_index!(
             @attrs        [$(#[$attrs])*]
             @type         [$type]
             @max          [$max]
@@ -329,7 +330,7 @@ macro_rules! newtype_index {
                    derive [$($derives:ident,)+]
                    ENCODABLE = custom
                    $($tokens:tt)*) => (
-        newtype_index!(
+        $crate::newtype_index!(
             @attrs        [$(#[$attrs])*]
             @derives      [$($derives,)+]
             @type         [$type]
@@ -348,7 +349,7 @@ macro_rules! newtype_index {
      @debug_format [$debug_format:tt]
                    derive [$($derives:ident,)+]
                    $($tokens:tt)*) => (
-        newtype_index!(
+        $crate::newtype_index!(
             @derives      [$($derives,)+ RustcEncodable,]
             @attrs        [$(#[$attrs])*]
             @type         [$type]
@@ -356,7 +357,7 @@ macro_rules! newtype_index {
             @vis          [$v]
             @debug_format [$debug_format]
                           $($tokens)*);
-        newtype_index!(@decodable $type);
+        $crate::newtype_index!(@decodable $type);
     );
 
     // The case where no derives are added, but encodable is overridden. Don't
@@ -368,7 +369,7 @@ macro_rules! newtype_index {
      @debug_format [$debug_format:tt]
                    ENCODABLE = custom
                    $($tokens:tt)*) => (
-        newtype_index!(
+        $crate::newtype_index!(
             @derives      []
             @attrs        [$(#[$attrs])*]
             @type         [$type]
@@ -385,7 +386,7 @@ macro_rules! newtype_index {
      @vis          [$v:vis]
      @debug_format [$debug_format:tt]
                    $($tokens:tt)*) => (
-        newtype_index!(
+        $crate::newtype_index!(
             @derives      [RustcEncodable,]
             @attrs        [$(#[$attrs])*]
             @type         [$type]
@@ -393,7 +394,7 @@ macro_rules! newtype_index {
             @vis          [$v]
             @debug_format [$debug_format]
                           $($tokens)*);
-        newtype_index!(@decodable $type);
+        $crate::newtype_index!(@decodable $type);
     );
 
     (@decodable $type:ident) => (
@@ -420,7 +421,7 @@ macro_rules! newtype_index {
      @vis          [$v:vis]
      @debug_format [$debug_format:tt]
                    $name:ident = $constant:expr) => (
-        newtype_index!(
+        $crate::newtype_index!(
             @derives      [$($derives,)*]
             @attrs        [$(#[$attrs])*]
             @type         [$type]
@@ -439,7 +440,7 @@ macro_rules! newtype_index {
      @debug_format [$debug_format:tt]
                    $(#[doc = $doc:expr])*
                    const $name:ident = $constant:expr) => (
-        newtype_index!(
+        $crate::newtype_index!(
             @derives      [$($derives,)*]
             @attrs        [$(#[$attrs])*]
             @type         [$type]
@@ -458,7 +459,7 @@ macro_rules! newtype_index {
      @debug_format [$debug_format:tt]
                    MAX = $max:expr,
                    $($tokens:tt)*) => (
-        newtype_index!(
+        $crate::newtype_index!(
             @derives      [$($derives,)*]
             @attrs        [$(#[$attrs])*]
             @type         [$type]
@@ -477,7 +478,7 @@ macro_rules! newtype_index {
      @debug_format [$_debug_format:tt]
                    DEBUG_FORMAT = $debug_format:tt,
                    $($tokens:tt)*) => (
-        newtype_index!(
+        $crate::newtype_index!(
             @derives      [$($derives,)*]
             @attrs        [$(#[$attrs])*]
             @type         [$type]
@@ -499,7 +500,7 @@ macro_rules! newtype_index {
                    $($tokens:tt)*) => (
         $(#[doc = $doc])*
         pub const $name: $type = $type::from_u32_const($constant);
-        newtype_index!(
+        $crate::newtype_index!(
             @derives      [$($derives,)*]
             @attrs        [$(#[$attrs])*]
             @type         [$type]
diff --git a/src/librustc_mir/lib.rs b/src/librustc_mir/lib.rs
index 4a80534503a..f5e4661afa6 100644
--- a/src/librustc_mir/lib.rs
+++ b/src/librustc_mir/lib.rs
@@ -15,12 +15,10 @@ Rust MIR: a lowered representation of Rust. Also: an experiment!
 #![feature(decl_macro)]
 #![feature(exhaustive_patterns)]
 #![feature(rustc_diagnostic_macros)]
-#![feature(rustc_attrs)]
 #![feature(never_type)]
 #![feature(specialization)]
 #![feature(try_trait)]
 #![feature(unicode_internals)]
-#![feature(step_trait)]
 #![feature(slice_concat_ext)]
 #![feature(trusted_len)]
 #![feature(try_blocks)]
diff --git a/src/librustc_target/abi/mod.rs b/src/librustc_target/abi/mod.rs
index 55cb1791443..01586e92aeb 100644
--- a/src/librustc_target/abi/mod.rs
+++ b/src/librustc_target/abi/mod.rs
@@ -6,6 +6,7 @@ use crate::spec::Target;
 use std::fmt;
 use std::ops::{Add, Deref, Sub, Mul, AddAssign, Range, RangeInclusive};
 
+use rustc_data_structures::newtype_index;
 use rustc_data_structures::indexed_vec::{Idx, IndexVec};
 use syntax_pos::symbol::{sym, Symbol};
 
diff --git a/src/librustc_target/lib.rs b/src/librustc_target/lib.rs
index c1ec4e59ef2..dcd1eb5acdc 100644
--- a/src/librustc_target/lib.rs
+++ b/src/librustc_target/lib.rs
@@ -11,9 +11,7 @@
 
 #![feature(box_syntax)]
 #![feature(nll)]
-#![feature(rustc_attrs)]
 #![feature(slice_patterns)]
-#![feature(step_trait)]
 
 #![deny(rust_2018_idioms)]
 #![deny(unused_lifetimes)]
@@ -23,8 +21,5 @@
 #[allow(unused_extern_crates)]
 extern crate serialize as rustc_serialize; // used by deriving
 
-#[macro_use]
-extern crate rustc_data_structures;
-
 pub mod abi;
 pub mod spec;
diff --git a/src/libsyntax/lib.rs b/src/libsyntax/lib.rs
index ee7fb97ffd7..591f2fb599b 100644
--- a/src/libsyntax/lib.rs
+++ b/src/libsyntax/lib.rs
@@ -18,9 +18,7 @@
 #![feature(label_break_value)]
 #![feature(mem_take)]
 #![feature(nll)]
-#![feature(rustc_attrs)]
 #![feature(rustc_diagnostic_macros)]
-#![feature(step_trait)]
 #![feature(try_trait)]
 #![feature(unicode_internals)]
 
diff --git a/src/test/run-pass-fulldeps/newtype_index.rs b/src/test/run-pass-fulldeps/newtype_index.rs
index 18b845eeecb..1192a44a6ee 100644
--- a/src/test/run-pass-fulldeps/newtype_index.rs
+++ b/src/test/run-pass-fulldeps/newtype_index.rs
@@ -1,9 +1,9 @@
-#![feature(rustc_attrs, rustc_private, step_trait)]
+#![feature(rustc_private)]
 
-#[macro_use] extern crate rustc_data_structures;
+extern crate rustc_data_structures;
 extern crate serialize as rustc_serialize;
 
-use rustc_data_structures::indexed_vec::Idx;
+use rustc_data_structures::{newtype_index, indexed_vec::Idx};
 
 newtype_index!(struct MyIdx { MAX = 0xFFFF_FFFA });