Rename `syntax` to `rustc_ast` in source code

291 files changed, 650 insertions, 637 deletions

diff --git a/src/doc/unstable-book/src/language-features/plugin.md b/src/doc/unstable-book/src/language-features/plugin.md
index f6e3d701148..47ac986c224 100644
--- a/src/doc/unstable-book/src/language-features/plugin.md
+++ b/src/doc/unstable-book/src/language-features/plugin.md
@@ -42,7 +42,7 @@ that warns about any item named `lintme`.
 #![feature(plugin_registrar)]
 #![feature(box_syntax, rustc_private)]
 
-extern crate syntax;
+extern crate rustc_ast;
 
 // Load rustc as a plugin to get macros
 #[macro_use]
@@ -52,7 +52,7 @@ extern crate rustc_driver;
 use rustc::lint::{EarlyContext, LintContext, LintPass, EarlyLintPass,
                   EarlyLintPassObject, LintArray};
 use rustc_driver::plugin::Registry;
-use syntax::ast;
+use rustc_ast::ast;
 
 declare_lint!(TEST_LINT, Warn, "Warn about items named 'lintme'");
 
diff --git a/src/librustc/Cargo.toml b/src/librustc/Cargo.toml
index e625015128b..bac2540ab45 100644
--- a/src/librustc/Cargo.toml
+++ b/src/librustc/Cargo.toml
@@ -28,7 +28,7 @@ rustc_data_structures = { path = "../librustc_data_structures" }
 rustc_errors = { path = "../librustc_errors" }
 rustc_index = { path = "../librustc_index" }
 rustc_serialize = { path = "../libserialize", package = "serialize" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
 backtrace = "0.3.40"
 parking_lot = "0.9"
diff --git a/src/librustc/arena.rs b/src/librustc/arena.rs
index 16920947c80..0384a9f7815 100644
--- a/src/librustc/arena.rs
+++ b/src/librustc/arena.rs
@@ -131,7 +131,7 @@ macro_rules! arena_types {
             // HIR types
             [few] hir_krate: rustc_hir::Crate<$tcx>,
             [] arm: rustc_hir::Arm<$tcx>,
-            [] attribute: syntax::ast::Attribute,
+            [] attribute: rustc_ast::ast::Attribute,
             [] block: rustc_hir::Block<$tcx>,
             [] bare_fn_ty: rustc_hir::BareFnTy<$tcx>,
             [few] global_asm: rustc_hir::GlobalAsm,
diff --git a/src/librustc/dep_graph/safe.rs b/src/librustc/dep_graph/safe.rs
index 23aef0c4298..74e32867cde 100644
--- a/src/librustc/dep_graph/safe.rs
+++ b/src/librustc/dep_graph/safe.rs
@@ -2,9 +2,9 @@
 
 use crate::ty::TyCtxt;
 
+use rustc_ast::ast::NodeId;
 use rustc_hir::def_id::DefId;
 use rustc_hir::BodyId;
-use syntax::ast::NodeId;
 
 /// The `DepGraphSafe` trait is used to specify what kinds of values
 /// are safe to "leak" into a task. The idea is that this should be
diff --git a/src/librustc/hir/exports.rs b/src/librustc/hir/exports.rs
index db020e39e8e..4c144a54d63 100644
--- a/src/librustc/hir/exports.rs
+++ b/src/librustc/hir/exports.rs
@@ -1,10 +1,10 @@
 use crate::ty;
 
+use rustc_ast::ast;
 use rustc_hir::def::Res;
 use rustc_hir::def_id::DefIdMap;
 use rustc_macros::HashStable;
 use rustc_span::Span;
-use syntax::ast;
 
 use std::fmt::Debug;
 
diff --git a/src/librustc/hir/map/blocks.rs b/src/librustc/hir/map/blocks.rs
index 016fc939a7a..618f9a018d1 100644
--- a/src/librustc/hir/map/blocks.rs
+++ b/src/librustc/hir/map/blocks.rs
@@ -12,11 +12,11 @@
 //! for the `Code` associated with a particular NodeId.
 
 use crate::hir::map::Map;
+use rustc_ast::ast::{Attribute, Ident};
 use rustc_hir as hir;
 use rustc_hir::intravisit::FnKind;
 use rustc_hir::{Expr, FnDecl, Node};
 use rustc_span::Span;
-use syntax::ast::{Attribute, Ident};
 
 /// An FnLikeNode is a Node that is like a fn, in that it has a decl
 /// and a body (as well as a NodeId, a span, etc).
diff --git a/src/librustc/hir/map/collector.rs b/src/librustc/hir/map/collector.rs
index bf1fc09649a..ebd335ab355 100644
--- a/src/librustc/hir/map/collector.rs
+++ b/src/librustc/hir/map/collector.rs
@@ -3,6 +3,7 @@ use crate::hir::map::definitions::{self, DefPathHash};
 use crate::hir::map::{Entry, HirEntryMap, Map};
 use crate::ich::StableHashingContext;
 use crate::middle::cstore::CrateStore;
+use rustc_ast::ast::NodeId;
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
@@ -16,7 +17,6 @@ use rustc_index::vec::IndexVec;
 use rustc_session::{CrateDisambiguator, Session};
 use rustc_span::source_map::SourceMap;
 use rustc_span::{Span, Symbol, DUMMY_SP};
-use syntax::ast::NodeId;
 
 use std::iter::repeat;
 
diff --git a/src/librustc/hir/map/definitions.rs b/src/librustc/hir/map/definitions.rs
index 048c1f026be..047ce8b8445 100644
--- a/src/librustc/hir/map/definitions.rs
+++ b/src/librustc/hir/map/definitions.rs
@@ -4,6 +4,8 @@
 //! There are also some rather random cases (like const initializer
 //! expressions) that are mostly just leftovers.
 
+use rustc_ast::ast;
+use rustc_ast::node_id::NodeMap;
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::stable_hasher::StableHasher;
@@ -14,8 +16,6 @@ use rustc_session::CrateDisambiguator;
 use rustc_span::hygiene::ExpnId;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
-use syntax::ast;
-use syntax::node_id::NodeMap;
 
 use std::borrow::Borrow;
 use std::fmt::Write;
diff --git a/src/librustc/hir/map/mod.rs b/src/librustc/hir/map/mod.rs
index f7301280acd..b2088265605 100644
--- a/src/librustc/hir/map/mod.rs
+++ b/src/librustc/hir/map/mod.rs
@@ -6,6 +6,7 @@ pub use self::definitions::{
 use crate::dep_graph::{DepGraph, DepKind, DepNode, DepNodeIndex};
 use crate::middle::cstore::CrateStoreDyn;
 use crate::ty::query::Providers;
+use rustc_ast::ast::{self, Name, NodeId};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::svh::Svh;
 use rustc_hir::def::{DefKind, Res};
@@ -20,7 +21,6 @@ use rustc_span::source_map::Spanned;
 use rustc_span::symbol::kw;
 use rustc_span::Span;
 use rustc_target::spec::abi::Abi;
-use syntax::ast::{self, Name, NodeId};
 
 pub mod blocks;
 mod collector;
diff --git a/src/librustc/ich/hcx.rs b/src/librustc/ich/hcx.rs
index 2cb8388aca6..d421da6d752 100644
--- a/src/librustc/ich/hcx.rs
+++ b/src/librustc/ich/hcx.rs
@@ -5,6 +5,7 @@ use crate::middle::cstore::CrateStore;
 use crate::session::Session;
 use crate::ty::{fast_reject, TyCtxt};
 
+use rustc_ast::ast;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher, ToStableHashKey};
 use rustc_data_structures::sync::Lrc;
@@ -13,7 +14,6 @@ use rustc_hir::def_id::{DefId, DefIndex};
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::Symbol;
 use rustc_span::{BytePos, SourceFile};
-use syntax::ast;
 
 use smallvec::SmallVec;
 use std::cmp::Ord;
diff --git a/src/librustc/ich/impls_syntax.rs b/src/librustc/ich/impls_syntax.rs
index a601ec7608e..daff8a0f182 100644
--- a/src/librustc/ich/impls_syntax.rs
+++ b/src/librustc/ich/impls_syntax.rs
@@ -3,10 +3,10 @@
 
 use crate::ich::StableHashingContext;
 
+use rustc_ast::ast;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_INDEX};
 use rustc_span::SourceFile;
-use syntax::ast;
 
 use smallvec::SmallVec;
 
@@ -35,7 +35,7 @@ impl<'a> HashStable<StableHashingContext<'a>> for [ast::Attribute] {
     }
 }
 
-impl<'ctx> syntax::HashStableContext for StableHashingContext<'ctx> {
+impl<'ctx> rustc_ast::HashStableContext for StableHashingContext<'ctx> {
     fn hash_attr(&mut self, attr: &ast::Attribute, hasher: &mut StableHasher) {
         // Make sure that these have been filtered out.
         debug_assert!(!attr.ident().map_or(false, |ident| self.is_ignored_attr(ident.name)));
diff --git a/src/librustc/middle/cstore.rs b/src/librustc/middle/cstore.rs
index 0e7ff3a3393..624bd934098 100644
--- a/src/librustc/middle/cstore.rs
+++ b/src/librustc/middle/cstore.rs
@@ -8,6 +8,8 @@ use crate::session::search_paths::PathKind;
 use crate::session::CrateDisambiguator;
 use crate::ty::TyCtxt;
 
+use rustc_ast::ast;
+use rustc_ast::expand::allocator::AllocatorKind;
 use rustc_data_structures::svh::Svh;
 use rustc_data_structures::sync::{self, MetadataRef};
 use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
@@ -17,8 +19,6 @@ use rustc_span::Span;
 use rustc_target::spec::Target;
 use std::any::Any;
 use std::path::{Path, PathBuf};
-use syntax::ast;
-use syntax::expand::allocator::AllocatorKind;
 
 pub use self::NativeLibraryKind::*;
 pub use rustc_session::utils::NativeLibraryKind;
diff --git a/src/librustc/middle/recursion_limit.rs b/src/librustc/middle/recursion_limit.rs
index be530da5910..ae31a2cc63d 100644
--- a/src/librustc/middle/recursion_limit.rs
+++ b/src/librustc/middle/recursion_limit.rs
@@ -8,8 +8,8 @@
 use crate::session::Session;
 use core::num::IntErrorKind;
 use rustc::bug;
+use rustc_ast::ast;
 use rustc_span::symbol::{sym, Symbol};
-use syntax::ast;
 
 use rustc_data_structures::sync::Once;
 
diff --git a/src/librustc/middle/stability.rs b/src/librustc/middle/stability.rs
index 7b5faa2423a..9d3df9623bd 100644
--- a/src/librustc/middle/stability.rs
+++ b/src/librustc/middle/stability.rs
@@ -5,6 +5,7 @@ pub use self::StabilityLevel::*;
 
 use crate::session::{DiagnosticMessageId, Session};
 use crate::ty::{self, TyCtxt};
+use rustc_ast::ast::CRATE_NODE_ID;
 use rustc_attr::{self as attr, ConstStability, Deprecation, RustcDeprecation, Stability};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::{Applicability, DiagnosticBuilder};
@@ -18,7 +19,6 @@ use rustc_session::lint::{BuiltinLintDiagnostics, Lint, LintBuffer};
 use rustc_session::parse::feature_err_issue;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{MultiSpan, Span};
-use syntax::ast::CRATE_NODE_ID;
 
 use std::num::NonZeroU32;
 
diff --git a/src/librustc/mir/interpret/allocation.rs b/src/librustc/mir/interpret/allocation.rs
index 0d0aa8a232e..d3efe62e8c1 100644
--- a/src/librustc/mir/interpret/allocation.rs
+++ b/src/librustc/mir/interpret/allocation.rs
@@ -6,12 +6,12 @@ use super::{
 
 use crate::ty::layout::{Align, Size};
 
+use rustc_ast::ast::Mutability;
 use rustc_data_structures::sorted_map::SortedMap;
 use rustc_target::abi::HasDataLayout;
 use std::borrow::Cow;
 use std::iter;
 use std::ops::{Deref, DerefMut, Range};
-use syntax::ast::Mutability;
 
 // NOTE: When adding new fields, make sure to adjust the `Snapshot` impl in
 // `src/librustc_mir/interpret/snapshot.rs`.
diff --git a/src/librustc/mir/interpret/mod.rs b/src/librustc/mir/interpret/mod.rs
index c62f9a049a0..64c07b431db 100644
--- a/src/librustc/mir/interpret/mod.rs
+++ b/src/librustc/mir/interpret/mod.rs
@@ -107,6 +107,7 @@ use crate::ty::layout::{self, Size};
 use crate::ty::subst::GenericArgKind;
 use crate::ty::{self, Instance, Ty, TyCtxt};
 use byteorder::{BigEndian, LittleEndian, ReadBytesExt, WriteBytesExt};
+use rustc_ast::ast::LitKind;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::{HashMapExt, Lock};
 use rustc_data_structures::tiny_list::TinyList;
@@ -117,7 +118,6 @@ use std::fmt;
 use std::io;
 use std::num::NonZeroU32;
 use std::sync::atomic::{AtomicU32, Ordering};
-use syntax::ast::LitKind;
 
 /// Uniquely identifies one of the following:
 /// - A constant
diff --git a/src/librustc/mir/mod.rs b/src/librustc/mir/mod.rs
index a415c72d0ba..668240ab42b 100644
--- a/src/librustc/mir/mod.rs
+++ b/src/librustc/mir/mod.rs
@@ -18,6 +18,8 @@ use rustc_hir::def_id::DefId;
 use rustc_hir::{self, GeneratorKind};
 
 use polonius_engine::Atom;
+pub use rustc_ast::ast::Mutability;
+use rustc_ast::ast::Name;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::graph::dominators::Dominators;
 use rustc_data_structures::graph::{self, GraphSuccessors};
@@ -32,8 +34,6 @@ use std::fmt::{self, Debug, Display, Formatter, Write};
 use std::ops::Index;
 use std::slice;
 use std::{iter, mem, option, u32};
-pub use syntax::ast::Mutability;
-use syntax::ast::Name;
 
 pub use self::cache::{BodyAndCache, ReadOnlyBodyAndCache};
 pub use self::query::*;
diff --git a/src/librustc/traits/mod.rs b/src/librustc/traits/mod.rs
index 77c612cf34a..1a4ea66a5f1 100644
--- a/src/librustc/traits/mod.rs
+++ b/src/librustc/traits/mod.rs
@@ -13,11 +13,11 @@ use crate::ty::fold::{TypeFolder, TypeVisitor};
 use crate::ty::subst::SubstsRef;
 use crate::ty::{self, AdtKind, List, Ty, TyCtxt};
 
+use rustc_ast::ast;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_span::{Span, DUMMY_SP};
 use smallvec::SmallVec;
-use syntax::ast;
 
 use std::borrow::Cow;
 use std::fmt::Debug;
diff --git a/src/librustc/traits/specialization_graph.rs b/src/librustc/traits/specialization_graph.rs
index ee813bf606e..d481e578fc1 100644
--- a/src/librustc/traits/specialization_graph.rs
+++ b/src/librustc/traits/specialization_graph.rs
@@ -1,10 +1,10 @@
 use crate::ich::{self, StableHashingContext};
 use crate::ty::fast_reject::SimplifiedType;
 use crate::ty::{self, TyCtxt};
+use rustc_ast::ast::Ident;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_hir::def_id::{DefId, DefIdMap};
-use syntax::ast::Ident;
 
 /// A per-trait graph of impls in specialization order. At the moment, this
 /// graph forms a tree rooted with the trait itself, with all other nodes
diff --git a/src/librustc/ty/cast.rs b/src/librustc/ty/cast.rs
index 5ba3f80b822..31c106cb230 100644
--- a/src/librustc/ty/cast.rs
+++ b/src/librustc/ty/cast.rs
@@ -3,8 +3,8 @@
 
 use crate::ty::{self, Ty};
 
+use rustc_ast::ast;
 use rustc_macros::HashStable;
-use syntax::ast;
 
 /// Types that are represented as ints.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
diff --git a/src/librustc/ty/context.rs b/src/librustc/ty/context.rs
index cd229728f4b..d2108517a06 100644
--- a/src/librustc/ty/context.rs
+++ b/src/librustc/ty/context.rs
@@ -42,6 +42,9 @@ use crate::ty::{InferConst, ParamConst};
 use crate::ty::{List, TyKind, TyS};
 use crate::util::common::ErrorReported;
 use rustc::lint::LintDiagnosticBuilder;
+use rustc_ast::ast;
+use rustc_ast::expand::allocator::AllocatorKind;
+use rustc_ast::node_id::NodeMap;
 use rustc_attr as attr;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::profiling::SelfProfilerRef;
@@ -65,9 +68,6 @@ use rustc_span::source_map::MultiSpan;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
 use rustc_target::spec::abi;
-use syntax::ast;
-use syntax::expand::allocator::AllocatorKind;
-use syntax::node_id::NodeMap;
 
 use smallvec::SmallVec;
 use std::any::Any;
diff --git a/src/librustc/ty/error.rs b/src/librustc/ty/error.rs
index 2599ad8ba7b..d0bc0d5fabf 100644
--- a/src/librustc/ty/error.rs
+++ b/src/librustc/ty/error.rs
@@ -1,10 +1,10 @@
 use crate::ty::{self, BoundRegion, Region, Ty, TyCtxt};
+use rustc_ast::ast;
 use rustc_errors::{pluralize, Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_span::Span;
 use rustc_target::spec::abi;
-use syntax::ast;
 
 use std::borrow::Cow;
 use std::fmt;
diff --git a/src/librustc/ty/fast_reject.rs b/src/librustc/ty/fast_reject.rs
index 5aa8bd9df2a..2a937d6581d 100644
--- a/src/librustc/ty/fast_reject.rs
+++ b/src/librustc/ty/fast_reject.rs
@@ -1,11 +1,11 @@
 use crate::ich::StableHashingContext;
 use crate::ty::{self, Ty, TyCtxt};
+use rustc_ast::ast;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_hir::def_id::DefId;
 use std::fmt::Debug;
 use std::hash::Hash;
 use std::mem;
-use syntax::ast;
 
 use self::SimplifiedTypeGen::*;
 
diff --git a/src/librustc/ty/layout.rs b/src/librustc/ty/layout.rs
index cb98ff4c9e5..a8266f405cb 100644
--- a/src/librustc/ty/layout.rs
+++ b/src/librustc/ty/layout.rs
@@ -1,9 +1,9 @@
 use crate::session::{self, DataTypeKind};
 use crate::ty::{self, subst::SubstsRef, ReprOptions, Ty, TyCtxt, TypeFoldable};
 
+use rustc_ast::ast::{self, Ident, IntTy, UintTy};
 use rustc_attr as attr;
 use rustc_span::DUMMY_SP;
-use syntax::ast::{self, Ident, IntTy, UintTy};
 
 use std::cmp;
 use std::fmt;
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index 4c7046781c1..89ff0b2a0cc 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -26,6 +26,8 @@ use crate::ty::layout::VariantIdx;
 use crate::ty::subst::{InternalSubsts, Subst, SubstsRef};
 use crate::ty::util::{Discr, IntTypeExt};
 use crate::ty::walk::TypeWalker;
+use rustc_ast::ast::{self, Ident, Name};
+use rustc_ast::node_id::{NodeId, NodeMap, NodeSet};
 use rustc_attr as attr;
 use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::FxHashMap;
@@ -44,8 +46,6 @@ use rustc_span::hygiene::ExpnId;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
 use rustc_target::abi::Align;
-use syntax::ast::{self, Ident, Name};
-use syntax::node_id::{NodeId, NodeMap, NodeSet};
 
 use std::cell::RefCell;
 use std::cmp::{self, Ordering};
diff --git a/src/librustc/ty/print/pretty.rs b/src/librustc/ty/print/pretty.rs
index 3512b24ec48..3bf92552c86 100644
--- a/src/librustc/ty/print/pretty.rs
+++ b/src/librustc/ty/print/pretty.rs
@@ -11,10 +11,10 @@ use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_INDEX, LOCAL_CRATE};
 
 use rustc_apfloat::ieee::{Double, Single};
 use rustc_apfloat::Float;
+use rustc_ast::ast;
 use rustc_attr::{SignedInt, UnsignedInt};
 use rustc_span::symbol::{kw, Symbol};
 use rustc_target::spec::abi::Abi;
-use syntax::ast;
 
 use std::cell::Cell;
 use std::collections::BTreeMap;
diff --git a/src/librustc/ty/query/job.rs b/src/librustc/ty/query/job.rs
index 3394fed8402..4e88fc54637 100644
--- a/src/librustc/ty/query/job.rs
+++ b/src/librustc/ty/query/job.rs
@@ -535,11 +535,11 @@ pub unsafe fn handle_deadlock() {
     let rustc_span_globals =
         rustc_span::GLOBALS.with(|rustc_span_globals| rustc_span_globals as *const _);
     let rustc_span_globals = &*rustc_span_globals;
-    let syntax_globals = syntax::attr::GLOBALS.with(|syntax_globals| syntax_globals as *const _);
+    let syntax_globals = rustc_ast::attr::GLOBALS.with(|syntax_globals| syntax_globals as *const _);
     let syntax_globals = &*syntax_globals;
     thread::spawn(move || {
         tls::GCX_PTR.set(gcx_ptr, || {
-            syntax::attr::GLOBALS.set(syntax_globals, || {
+            rustc_ast::attr::GLOBALS.set(syntax_globals, || {
                 rustc_span::GLOBALS
                     .set(rustc_span_globals, || tls::with_global(|tcx| deadlock(tcx, &registry)))
             });
diff --git a/src/librustc/ty/query/mod.rs b/src/librustc/ty/query/mod.rs
index 381a7b1f03f..8614fd5cdca 100644
--- a/src/librustc/ty/query/mod.rs
+++ b/src/librustc/ty/query/mod.rs
@@ -49,6 +49,7 @@ use rustc_hir::{Crate, HirIdSet, ItemLocalId, TraitCandidate};
 use rustc_index::vec::IndexVec;
 use rustc_target::spec::PanicStrategy;
 
+use rustc_ast::ast;
 use rustc_attr as attr;
 use rustc_span::symbol::Symbol;
 use rustc_span::{Span, DUMMY_SP};
@@ -56,7 +57,6 @@ use std::borrow::Cow;
 use std::convert::TryFrom;
 use std::ops::Deref;
 use std::sync::Arc;
-use syntax::ast;
 
 #[macro_use]
 mod plumbing;
diff --git a/src/librustc/ty/query/on_disk_cache.rs b/src/librustc/ty/query/on_disk_cache.rs
index f96bf6c110c..109ac97fe62 100644
--- a/src/librustc/ty/query/on_disk_cache.rs
+++ b/src/librustc/ty/query/on_disk_cache.rs
@@ -7,6 +7,7 @@ use crate::session::{CrateDisambiguator, Session};
 use crate::ty::codec::{self as ty_codec, TyDecoder, TyEncoder};
 use crate::ty::context::TyCtxt;
 use crate::ty::{self, Ty};
+use rustc_ast::ast::Ident;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::{HashMapExt, Lock, Lrc, Once};
 use rustc_data_structures::thin_vec::ThinVec;
@@ -22,7 +23,6 @@ use rustc_span::hygiene::{ExpnId, SyntaxContext};
 use rustc_span::source_map::{SourceMap, StableSourceFileId};
 use rustc_span::{BytePos, SourceFile, Span, DUMMY_SP};
 use std::mem;
-use syntax::ast::Ident;
 
 const TAG_FILE_FOOTER: u128 = 0xC0FFEE_C0FFEE_C0FFEE_C0FFEE_C0FFEE;
 
diff --git a/src/librustc/ty/structural_impls.rs b/src/librustc/ty/structural_impls.rs
index 03ff1b8a317..e2fa0313911 100644
--- a/src/librustc/ty/structural_impls.rs
+++ b/src/librustc/ty/structural_impls.rs
@@ -260,8 +260,8 @@ CloneTypeFoldableAndLiftImpls! {
     u64,
     String,
     crate::middle::region::Scope,
-    ::syntax::ast::FloatTy,
-    ::syntax::ast::NodeId,
+    ::rustc_ast::ast::FloatTy,
+    ::rustc_ast::ast::NodeId,
     ::rustc_span::symbol::Symbol,
     ::rustc_hir::def::Res,
     ::rustc_hir::def_id::DefId,
diff --git a/src/librustc/ty/sty.rs b/src/librustc/ty/sty.rs
index 60ea44bfa9d..fcf23b9023b 100644
--- a/src/librustc/ty/sty.rs
+++ b/src/librustc/ty/sty.rs
@@ -17,6 +17,7 @@ use crate::ty::{
 };
 use crate::ty::{List, ParamEnv, ParamEnvAnd, TyS};
 use polonius_engine::Atom;
+use rustc_ast::ast::{self, Ident};
 use rustc_data_structures::captures::Captures;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
@@ -29,7 +30,6 @@ use std::borrow::Cow;
 use std::cmp::Ordering;
 use std::marker::PhantomData;
 use std::ops::Range;
-use syntax::ast::{self, Ident};
 
 #[derive(
     Clone,
diff --git a/src/librustc/ty/util.rs b/src/librustc/ty/util.rs
index eec6893d357..7b1f821877b 100644
--- a/src/librustc/ty/util.rs
+++ b/src/librustc/ty/util.rs
@@ -10,6 +10,7 @@ use crate::ty::TyKind::*;
 use crate::ty::{self, DefIdTree, GenericParamDefKind, Ty, TyCtxt, TypeFoldable};
 use crate::util::common::ErrorReported;
 use rustc_apfloat::Float as _;
+use rustc_ast::ast;
 use rustc_attr::{self as attr, SignedInt, UnsignedInt};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
@@ -21,7 +22,6 @@ use rustc_span::Span;
 use rustc_target::abi::TargetDataLayout;
 use smallvec::SmallVec;
 use std::{cmp, fmt};
-use syntax::ast;
 
 #[derive(Copy, Clone, Debug)]
 pub struct Discr<'tcx> {
diff --git a/src/librustc_ast_lowering/Cargo.toml b/src/librustc_ast_lowering/Cargo.toml
index 33b75b8136f..23dc80facae 100644
--- a/src/librustc_ast_lowering/Cargo.toml
+++ b/src/librustc_ast_lowering/Cargo.toml
@@ -20,5 +20,5 @@ rustc_index = { path = "../librustc_index" }
 rustc_span = { path = "../librustc_span" }
 rustc_errors = { path = "../librustc_errors" }
 rustc_session = { path = "../librustc_session" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
diff --git a/src/librustc_ast_lowering/expr.rs b/src/librustc_ast_lowering/expr.rs
index d781fbde59c..6708ffabaf9 100644
--- a/src/librustc_ast_lowering/expr.rs
+++ b/src/librustc_ast_lowering/expr.rs
@@ -1,15 +1,15 @@
 use super::{ImplTraitContext, LoweringContext, ParamMode, ParenthesizedGenericArgs};
 
 use rustc::bug;
+use rustc_ast::ast::*;
+use rustc_ast::attr;
+use rustc_ast::ptr::P as AstP;
 use rustc_data_structures::thin_vec::ThinVec;
 use rustc_errors::struct_span_err;
 use rustc_hir as hir;
 use rustc_hir::def::Res;
 use rustc_span::source_map::{respan, DesugaringKind, Span, Spanned};
 use rustc_span::symbol::{sym, Symbol};
-use syntax::ast::*;
-use syntax::attr;
-use syntax::ptr::P as AstP;
 
 impl<'hir> LoweringContext<'_, 'hir> {
     fn lower_exprs(&mut self, exprs: &[AstP<Expr>]) -> &'hir [hir::Expr<'hir>] {
@@ -783,7 +783,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         e2: Option<&Expr>,
         lims: RangeLimits,
     ) -> hir::ExprKind<'hir> {
-        use syntax::ast::RangeLimits::*;
+        use rustc_ast::ast::RangeLimits::*;
 
         let path = match (e1, e2, lims) {
             (None, None, HalfOpen) => sym::RangeFull,
diff --git a/src/librustc_ast_lowering/item.rs b/src/librustc_ast_lowering/item.rs
index b5e4fe90d0d..13148d97a67 100644
--- a/src/librustc_ast_lowering/item.rs
+++ b/src/librustc_ast_lowering/item.rs
@@ -3,6 +3,10 @@ use super::{ImplTraitContext, ImplTraitPosition, ImplTraitTypeIdVisitor};
 
 use rustc::arena::Arena;
 use rustc::bug;
+use rustc_ast::ast::*;
+use rustc_ast::attr;
+use rustc_ast::node_id::NodeMap;
+use rustc_ast::visit::{self, AssocCtxt, Visitor};
 use rustc_errors::struct_span_err;
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
@@ -11,10 +15,6 @@ use rustc_span::source_map::{respan, DesugaringKind};
 use rustc_span::symbol::{kw, sym};
 use rustc_span::Span;
 use rustc_target::spec::abi;
-use syntax::ast::*;
-use syntax::attr;
-use syntax::node_id::NodeMap;
-use syntax::visit::{self, AssocCtxt, Visitor};
 
 use log::debug;
 use smallvec::{smallvec, SmallVec};
diff --git a/src/librustc_ast_lowering/lib.rs b/src/librustc_ast_lowering/lib.rs
index 8bf9311bfc7..0f7ed9f72f8 100644
--- a/src/librustc_ast_lowering/lib.rs
+++ b/src/librustc_ast_lowering/lib.rs
@@ -39,6 +39,14 @@ use rustc::dep_graph::DepGraph;
 use rustc::hir::map::definitions::{DefKey, DefPathData, Definitions};
 use rustc::hir::map::Map;
 use rustc::{bug, span_bug};
+use rustc_ast::ast;
+use rustc_ast::ast::*;
+use rustc_ast::attr;
+use rustc_ast::node_id::NodeMap;
+use rustc_ast::token::{self, Nonterminal, Token};
+use rustc_ast::tokenstream::{TokenStream, TokenTree};
+use rustc_ast::visit::{self, AssocCtxt, Visitor};
+use rustc_ast::walk_list;
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::FxHashSet;
@@ -58,14 +66,6 @@ use rustc_span::hygiene::ExpnId;
 use rustc_span::source_map::{respan, DesugaringKind, ExpnData, ExpnKind};
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
-use syntax::ast;
-use syntax::ast::*;
-use syntax::attr;
-use syntax::node_id::NodeMap;
-use syntax::token::{self, Nonterminal, Token};
-use syntax::tokenstream::{TokenStream, TokenTree};
-use syntax::visit::{self, AssocCtxt, Visitor};
-use syntax::walk_list;
 
 use log::{debug, trace};
 use smallvec::{smallvec, SmallVec};
diff --git a/src/librustc_ast_lowering/pat.rs b/src/librustc_ast_lowering/pat.rs
index b42b12c4dd8..d6f4ba1529b 100644
--- a/src/librustc_ast_lowering/pat.rs
+++ b/src/librustc_ast_lowering/pat.rs
@@ -1,10 +1,10 @@
 use super::{ImplTraitContext, LoweringContext, ParamMode};
 
+use rustc_ast::ast::*;
+use rustc_ast::ptr::P;
 use rustc_hir as hir;
 use rustc_hir::def::Res;
 use rustc_span::{source_map::Spanned, Span};
-use syntax::ast::*;
-use syntax::ptr::P;
 
 impl<'a, 'hir> LoweringContext<'a, 'hir> {
     crate fn lower_pat(&mut self, p: &Pat) -> &'hir hir::Pat<'hir> {
diff --git a/src/librustc_ast_lowering/path.rs b/src/librustc_ast_lowering/path.rs
index 248874dbe46..80d7e3d0d46 100644
--- a/src/librustc_ast_lowering/path.rs
+++ b/src/librustc_ast_lowering/path.rs
@@ -3,6 +3,7 @@ use super::{GenericArgsCtor, ParenthesizedGenericArgs};
 
 use rustc::lint::builtin::ELIDED_LIFETIMES_IN_PATHS;
 use rustc::span_bug;
+use rustc_ast::ast::{self, *};
 use rustc_errors::{struct_span_err, Applicability};
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, PartialRes, Res};
@@ -10,7 +11,6 @@ use rustc_hir::def_id::DefId;
 use rustc_hir::GenericArg;
 use rustc_session::lint::BuiltinLintDiagnostics;
 use rustc_span::Span;
-use syntax::ast::{self, *};
 
 use log::debug;
 use smallvec::smallvec;
diff --git a/src/librustc_ast_passes/Cargo.toml b/src/librustc_ast_passes/Cargo.toml
index fe020ddba8e..5d096e4965d 100644
--- a/src/librustc_ast_passes/Cargo.toml
+++ b/src/librustc_ast_passes/Cargo.toml
@@ -18,4 +18,4 @@ rustc_feature = { path = "../librustc_feature" }
 rustc_parse = { path = "../librustc_parse" }
 rustc_session = { path = "../librustc_session" }
 rustc_span = { path = "../librustc_span" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
diff --git a/src/librustc_ast_passes/ast_validation.rs b/src/librustc_ast_passes/ast_validation.rs
index 0463ad7fb7b..9f04c01bfa8 100644
--- a/src/librustc_ast_passes/ast_validation.rs
+++ b/src/librustc_ast_passes/ast_validation.rs
@@ -6,6 +6,11 @@
 // This pass is supposed to perform only simple checks not requiring name resolution
 // or type checking or some other kind of complex analysis.
 
+use rustc_ast::ast::*;
+use rustc_ast::attr;
+use rustc_ast::expand::is_proc_macro_attr;
+use rustc_ast::visit::{self, AssocCtxt, FnCtxt, FnKind, Visitor};
+use rustc_ast::walk_list;
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::{error_code, struct_span_err, Applicability};
@@ -16,11 +21,6 @@ use rustc_session::Session;
 use rustc_span::symbol::{kw, sym};
 use rustc_span::Span;
 use std::mem;
-use syntax::ast::*;
-use syntax::attr;
-use syntax::expand::is_proc_macro_attr;
-use syntax::visit::{self, AssocCtxt, FnCtxt, FnKind, Visitor};
-use syntax::walk_list;
 
 const MORE_EXTERN: &str =
     "for more information, visit https://doc.rust-lang.org/std/keyword.extern.html";
diff --git a/src/librustc_ast_passes/feature_gate.rs b/src/librustc_ast_passes/feature_gate.rs
index 33ff0bc451b..05e69d0cfd7 100644
--- a/src/librustc_ast_passes/feature_gate.rs
+++ b/src/librustc_ast_passes/feature_gate.rs
@@ -1,3 +1,7 @@
+use rustc_ast::ast::{self, AssocTyConstraint, AssocTyConstraintKind, NodeId};
+use rustc_ast::ast::{GenericParam, GenericParamKind, PatKind, RangeEnd, VariantData};
+use rustc_ast::attr;
+use rustc_ast::visit::{self, AssocCtxt, FnCtxt, FnKind, Visitor};
 use rustc_errors::{struct_span_err, Handler};
 use rustc_feature::{AttributeGate, BUILTIN_ATTRIBUTE_MAP};
 use rustc_feature::{Features, GateIssue, UnstableFeatures};
@@ -5,10 +9,6 @@ use rustc_session::parse::{feature_err, feature_err_issue, ParseSess};
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::ast::{self, AssocTyConstraint, AssocTyConstraintKind, NodeId};
-use syntax::ast::{GenericParam, GenericParamKind, PatKind, RangeEnd, VariantData};
-use syntax::attr;
-use syntax::visit::{self, AssocCtxt, FnCtxt, FnKind, Visitor};
 
 use log::debug;
 
diff --git a/src/librustc_ast_passes/node_count.rs b/src/librustc_ast_passes/node_count.rs
index ed1ccdf6a76..16bcec8360e 100644
--- a/src/librustc_ast_passes/node_count.rs
+++ b/src/librustc_ast_passes/node_count.rs
@@ -1,8 +1,8 @@
 // Simply gives a rought count of the number of nodes in an AST.
 
+use rustc_ast::ast::*;
+use rustc_ast::visit::*;
 use rustc_span::Span;
-use syntax::ast::*;
-use syntax::visit::*;
 
 pub struct NodeCounter {
     pub count: usize,
diff --git a/src/librustc_ast_passes/show_span.rs b/src/librustc_ast_passes/show_span.rs
index 4596e8ff53d..73a66ba566b 100644
--- a/src/librustc_ast_passes/show_span.rs
+++ b/src/librustc_ast_passes/show_span.rs
@@ -5,9 +5,9 @@
 
 use std::str::FromStr;
 
-use syntax::ast;
-use syntax::visit;
-use syntax::visit::Visitor;
+use rustc_ast::ast;
+use rustc_ast::visit;
+use rustc_ast::visit::Visitor;
 
 enum Mode {
     Expression,
diff --git a/src/librustc_ast_pretty/Cargo.toml b/src/librustc_ast_pretty/Cargo.toml
index 41b8fad588d..82be095db88 100644
--- a/src/librustc_ast_pretty/Cargo.toml
+++ b/src/librustc_ast_pretty/Cargo.toml
@@ -13,4 +13,4 @@ doctest = false
 log = "0.4"
 rustc_span = { path = "../librustc_span" }
 rustc_data_structures = { path = "../librustc_data_structures" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
diff --git a/src/librustc_ast_pretty/pprust.rs b/src/librustc_ast_pretty/pprust.rs
index 76e1e7c175b..ea8535eabef 100644
--- a/src/librustc_ast_pretty/pprust.rs
+++ b/src/librustc_ast_pretty/pprust.rs
@@ -1,19 +1,19 @@
 use crate::pp::Breaks::{Consistent, Inconsistent};
 use crate::pp::{self, Breaks};
 
+use rustc_ast::ast::{self, BlockCheckMode, PatKind, RangeEnd, RangeSyntax};
+use rustc_ast::ast::{Attribute, GenericArg, MacArgs};
+use rustc_ast::ast::{GenericBound, SelfKind, TraitBoundModifier};
+use rustc_ast::attr;
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, BinOpToken, DelimToken, Nonterminal, Token, TokenKind};
+use rustc_ast::tokenstream::{self, TokenStream, TokenTree};
+use rustc_ast::util::parser::{self, AssocOp, Fixity};
+use rustc_ast::util::{classify, comments};
 use rustc_span::edition::Edition;
 use rustc_span::source_map::{SourceMap, Spanned};
 use rustc_span::symbol::{kw, sym, IdentPrinter};
 use rustc_span::{BytePos, FileName, Span};
-use syntax::ast::{self, BlockCheckMode, PatKind, RangeEnd, RangeSyntax};
-use syntax::ast::{Attribute, GenericArg, MacArgs};
-use syntax::ast::{GenericBound, SelfKind, TraitBoundModifier};
-use syntax::attr;
-use syntax::ptr::P;
-use syntax::token::{self, BinOpToken, DelimToken, Nonterminal, Token, TokenKind};
-use syntax::tokenstream::{self, TokenStream, TokenTree};
-use syntax::util::parser::{self, AssocOp, Fixity};
-use syntax::util::{classify, comments};
 
 use std::borrow::Cow;
 
diff --git a/src/librustc_ast_pretty/pprust/tests.rs b/src/librustc_ast_pretty/pprust/tests.rs
index 4531c7392a9..455f2e3da36 100644
--- a/src/librustc_ast_pretty/pprust/tests.rs
+++ b/src/librustc_ast_pretty/pprust/tests.rs
@@ -1,9 +1,9 @@
 use super::*;
 
+use rustc_ast::ast;
+use rustc_ast::with_default_globals;
 use rustc_span;
 use rustc_span::source_map::respan;
-use syntax::ast;
-use syntax::with_default_globals;
 
 fn fun_to_string(
     decl: &ast::FnDecl,
diff --git a/src/librustc_attr/Cargo.toml b/src/librustc_attr/Cargo.toml
index 66fcad2b1f1..8aaba15d84a 100644
--- a/src/librustc_attr/Cargo.toml
+++ b/src/librustc_attr/Cargo.toml
@@ -19,4 +19,4 @@ rustc_feature = { path = "../librustc_feature" }
 rustc_macros = { path = "../librustc_macros" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
 rustc_session = { path = "../librustc_session" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
diff --git a/src/librustc_attr/builtin.rs b/src/librustc_attr/builtin.rs
index e8deee5b1f3..08eae24da9b 100644
--- a/src/librustc_attr/builtin.rs
+++ b/src/librustc_attr/builtin.rs
@@ -2,6 +2,7 @@
 
 use super::{find_by_name, mark_used};
 
+use rustc_ast::ast::{self, Attribute, MetaItem, MetaItemKind, NestedMetaItem};
 use rustc_ast_pretty::pprust;
 use rustc_errors::{struct_span_err, Applicability, Handler};
 use rustc_feature::{find_gated_cfg, is_builtin_attr_name, Features, GatedCfg};
@@ -10,7 +11,6 @@ use rustc_session::parse::{feature_err, ParseSess};
 use rustc_span::hygiene::Transparency;
 use rustc_span::{symbol::sym, symbol::Symbol, Span};
 use std::num::NonZeroU32;
-use syntax::ast::{self, Attribute, MetaItem, MetaItemKind, NestedMetaItem};
 
 pub fn is_builtin_attr(attr: &Attribute) -> bool {
     attr.is_doc_comment() || attr.ident().filter(|ident| is_builtin_attr_name(ident.name)).is_some()
diff --git a/src/librustc_attr/lib.rs b/src/librustc_attr/lib.rs
index d2ff167db88..9803501fb96 100644
--- a/src/librustc_attr/lib.rs
+++ b/src/librustc_attr/lib.rs
@@ -1,6 +1,6 @@
 //! Functions and types dealing with attributes and meta items.
 //!
-//! FIXME(Centril): For now being, much of the logic is still in `syntax::attr`.
+//! FIXME(Centril): For now being, much of the logic is still in `rustc_ast::attr`.
 //! The goal is to move the definition of `MetaItem` and things that don't need to be in `syntax`
 //! to this crate.
 
@@ -11,6 +11,6 @@ pub use IntType::*;
 pub use ReprAttr::*;
 pub use StabilityLevel::*;
 
-pub use syntax::attr::*;
+pub use rustc_ast::attr::*;
 
-pub(crate) use syntax::HashStableContext;
+pub(crate) use rustc_ast::HashStableContext;
diff --git a/src/librustc_builtin_macros/Cargo.toml b/src/librustc_builtin_macros/Cargo.toml
index 501564221ae..c15438bde44 100644
--- a/src/librustc_builtin_macros/Cargo.toml
+++ b/src/librustc_builtin_macros/Cargo.toml
@@ -21,6 +21,6 @@ rustc_parse = { path = "../librustc_parse" }
 rustc_target = { path = "../librustc_target" }
 rustc_session = { path = "../librustc_session" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_expand = { path = "../librustc_expand" }
 rustc_span = { path = "../librustc_span" }
diff --git a/src/librustc_builtin_macros/asm.rs b/src/librustc_builtin_macros/asm.rs
index 9f98cf253c9..d9d99019963 100644
--- a/src/librustc_builtin_macros/asm.rs
+++ b/src/librustc_builtin_macros/asm.rs
@@ -2,15 +2,15 @@
 //
 use State::*;
 
+use rustc_ast::ast::{self, AsmDialect};
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, Token};
+use rustc_ast::tokenstream::{self, TokenStream};
 use rustc_errors::{struct_span_err, DiagnosticBuilder, PResult};
 use rustc_expand::base::*;
 use rustc_parse::parser::Parser;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
-use syntax::ast::{self, AsmDialect};
-use syntax::ptr::P;
-use syntax::token::{self, Token};
-use syntax::tokenstream::{self, TokenStream};
 
 enum State {
     Asm,
diff --git a/src/librustc_builtin_macros/assert.rs b/src/librustc_builtin_macros/assert.rs
index 3fc86a5469c..c58f004b3f2 100644
--- a/src/librustc_builtin_macros/assert.rs
+++ b/src/librustc_builtin_macros/assert.rs
@@ -1,14 +1,14 @@
 use rustc_errors::{Applicability, DiagnosticBuilder};
 
+use rustc_ast::ast::{self, *};
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, TokenKind};
+use rustc_ast::tokenstream::{DelimSpan, TokenStream, TokenTree};
 use rustc_ast_pretty::pprust;
 use rustc_expand::base::*;
 use rustc_parse::parser::Parser;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{Span, DUMMY_SP};
-use syntax::ast::{self, *};
-use syntax::ptr::P;
-use syntax::token::{self, TokenKind};
-use syntax::tokenstream::{DelimSpan, TokenStream, TokenTree};
 
 pub fn expand_assert<'cx>(
     cx: &'cx mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/cfg.rs b/src/librustc_builtin_macros/cfg.rs
index c9a77ee0acd..3c09b26af42 100644
--- a/src/librustc_builtin_macros/cfg.rs
+++ b/src/librustc_builtin_macros/cfg.rs
@@ -2,13 +2,13 @@
 //! a literal `true` or `false` based on whether the given cfg matches the
 //! current compilation environment.
 
+use rustc_ast::ast;
+use rustc_ast::token;
+use rustc_ast::tokenstream::TokenStream;
 use rustc_attr as attr;
 use rustc_errors::DiagnosticBuilder;
 use rustc_expand::base::{self, *};
 use rustc_span::Span;
-use syntax::ast;
-use syntax::token;
-use syntax::tokenstream::TokenStream;
 
 pub fn expand_cfg(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/cmdline_attrs.rs b/src/librustc_builtin_macros/cmdline_attrs.rs
index aa373d31e06..7ddbf08306b 100644
--- a/src/librustc_builtin_macros/cmdline_attrs.rs
+++ b/src/librustc_builtin_macros/cmdline_attrs.rs
@@ -1,11 +1,11 @@
 //! Attributes injected into the crate root from command line using `-Z crate-attr`.
 
+use rustc_ast::ast::{self, AttrItem, AttrStyle};
+use rustc_ast::attr::mk_attr;
+use rustc_ast::token;
 use rustc_expand::panictry;
 use rustc_session::parse::ParseSess;
 use rustc_span::FileName;
-use syntax::ast::{self, AttrItem, AttrStyle};
-use syntax::attr::mk_attr;
-use syntax::token;
 
 pub fn inject(mut krate: ast::Crate, parse_sess: &ParseSess, attrs: &[String]) -> ast::Crate {
     for raw_attr in attrs {
diff --git a/src/librustc_builtin_macros/compile_error.rs b/src/librustc_builtin_macros/compile_error.rs
index 4d8d168a2a8..f5955604e5f 100644
--- a/src/librustc_builtin_macros/compile_error.rs
+++ b/src/librustc_builtin_macros/compile_error.rs
@@ -1,8 +1,8 @@
 // The compiler code necessary to support the compile_error! extension.
 
+use rustc_ast::tokenstream::TokenStream;
 use rustc_expand::base::{self, *};
 use rustc_span::Span;
-use syntax::tokenstream::TokenStream;
 
 pub fn expand_compile_error<'cx>(
     cx: &'cx mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/concat.rs b/src/librustc_builtin_macros/concat.rs
index 1f1c8b8d21e..e0ce37b95fc 100644
--- a/src/librustc_builtin_macros/concat.rs
+++ b/src/librustc_builtin_macros/concat.rs
@@ -1,7 +1,7 @@
+use rustc_ast::ast;
+use rustc_ast::tokenstream::TokenStream;
 use rustc_expand::base::{self, DummyResult};
 use rustc_span::symbol::Symbol;
-use syntax::ast;
-use syntax::tokenstream::TokenStream;
 
 use std::string::String;
 
diff --git a/src/librustc_builtin_macros/concat_idents.rs b/src/librustc_builtin_macros/concat_idents.rs
index 449cb2a0b18..b55e71b2518 100644
--- a/src/librustc_builtin_macros/concat_idents.rs
+++ b/src/librustc_builtin_macros/concat_idents.rs
@@ -1,10 +1,10 @@
+use rustc_ast::ast;
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, Token};
+use rustc_ast::tokenstream::{TokenStream, TokenTree};
 use rustc_expand::base::{self, *};
 use rustc_span::symbol::Symbol;
 use rustc_span::Span;
-use syntax::ast;
-use syntax::ptr::P;
-use syntax::token::{self, Token};
-use syntax::tokenstream::{TokenStream, TokenTree};
 
 pub fn expand_concat_idents<'cx>(
     cx: &'cx mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/deriving/bounds.rs b/src/librustc_builtin_macros/deriving/bounds.rs
index ceb9aab4848..a1c818caff3 100644
--- a/src/librustc_builtin_macros/deriving/bounds.rs
+++ b/src/librustc_builtin_macros/deriving/bounds.rs
@@ -2,9 +2,9 @@ use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::path_std;
 
+use rustc_ast::ast::MetaItem;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::Span;
-use syntax::ast::MetaItem;
 
 pub fn expand_deriving_copy(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/deriving/clone.rs b/src/librustc_builtin_macros/deriving/clone.rs
index 0df5ef3c9d8..97569ef8138 100644
--- a/src/librustc_builtin_macros/deriving/clone.rs
+++ b/src/librustc_builtin_macros/deriving/clone.rs
@@ -2,11 +2,11 @@ use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::path_std;
 
+use rustc_ast::ast::{self, Expr, GenericArg, Generics, ItemKind, MetaItem, VariantData};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
-use syntax::ast::{self, Expr, GenericArg, Generics, ItemKind, MetaItem, VariantData};
-use syntax::ptr::P;
 
 pub fn expand_deriving_clone(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/deriving/cmp/eq.rs b/src/librustc_builtin_macros/deriving/cmp/eq.rs
index cb8933c1475..b39f41513ee 100644
--- a/src/librustc_builtin_macros/deriving/cmp/eq.rs
+++ b/src/librustc_builtin_macros/deriving/cmp/eq.rs
@@ -2,11 +2,11 @@ use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::path_std;
 
+use rustc_ast::ast::{self, Expr, GenericArg, Ident, MetaItem};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
-use syntax::ast::{self, Expr, GenericArg, Ident, MetaItem};
-use syntax::ptr::P;
 
 pub fn expand_deriving_eq(
     cx: &mut ExtCtxt<'_>,
@@ -16,8 +16,8 @@ pub fn expand_deriving_eq(
     push: &mut dyn FnMut(Annotatable),
 ) {
     let inline = cx.meta_word(span, sym::inline);
-    let hidden = syntax::attr::mk_nested_word_item(Ident::new(sym::hidden, span));
-    let doc = syntax::attr::mk_list_item(Ident::new(sym::doc, span), vec![hidden]);
+    let hidden = rustc_ast::attr::mk_nested_word_item(Ident::new(sym::hidden, span));
+    let doc = rustc_ast::attr::mk_list_item(Ident::new(sym::doc, span), vec![hidden]);
     let attrs = vec![cx.attribute(inline), cx.attribute(doc)];
     let trait_def = TraitDef {
         span,
diff --git a/src/librustc_builtin_macros/deriving/cmp/ord.rs b/src/librustc_builtin_macros/deriving/cmp/ord.rs
index fa430983806..b23fbc6f62b 100644
--- a/src/librustc_builtin_macros/deriving/cmp/ord.rs
+++ b/src/librustc_builtin_macros/deriving/cmp/ord.rs
@@ -2,11 +2,11 @@ use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::path_std;
 
+use rustc_ast::ast::{self, Expr, MetaItem};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::ast::{self, Expr, MetaItem};
-use syntax::ptr::P;
 
 pub fn expand_deriving_ord(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/deriving/cmp/partial_eq.rs b/src/librustc_builtin_macros/deriving/cmp/partial_eq.rs
index dc2912895a8..d3f1a9c15f4 100644
--- a/src/librustc_builtin_macros/deriving/cmp/partial_eq.rs
+++ b/src/librustc_builtin_macros/deriving/cmp/partial_eq.rs
@@ -2,11 +2,11 @@ use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::{path_local, path_std};
 
+use rustc_ast::ast::{BinOpKind, Expr, MetaItem};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::ast::{BinOpKind, Expr, MetaItem};
-use syntax::ptr::P;
 
 pub fn expand_deriving_partial_eq(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/deriving/cmp/partial_ord.rs b/src/librustc_builtin_macros/deriving/cmp/partial_ord.rs
index a54d8c56f75..835ccd1b022 100644
--- a/src/librustc_builtin_macros/deriving/cmp/partial_ord.rs
+++ b/src/librustc_builtin_macros/deriving/cmp/partial_ord.rs
@@ -4,11 +4,11 @@ use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::{path_local, path_std, pathvec_std};
 
+use rustc_ast::ast::{self, BinOpKind, Expr, MetaItem};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
-use syntax::ast::{self, BinOpKind, Expr, MetaItem};
-use syntax::ptr::P;
 
 pub fn expand_deriving_partial_ord(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/deriving/debug.rs b/src/librustc_builtin_macros/deriving/debug.rs
index f68fddee71b..f47be3c3c19 100644
--- a/src/librustc_builtin_macros/deriving/debug.rs
+++ b/src/librustc_builtin_macros/deriving/debug.rs
@@ -2,12 +2,12 @@ use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::path_std;
 
+use rustc_ast::ast::{self, Ident};
+use rustc_ast::ast::{Expr, MetaItem};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::symbol::sym;
 use rustc_span::{Span, DUMMY_SP};
-use syntax::ast::{self, Ident};
-use syntax::ast::{Expr, MetaItem};
-use syntax::ptr::P;
 
 pub fn expand_deriving_debug(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/deriving/decodable.rs b/src/librustc_builtin_macros/deriving/decodable.rs
index 3b20ebbbab4..ac5d08ba62d 100644
--- a/src/librustc_builtin_macros/deriving/decodable.rs
+++ b/src/librustc_builtin_macros/deriving/decodable.rs
@@ -4,12 +4,12 @@ use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::pathvec_std;
 
+use rustc_ast::ast;
+use rustc_ast::ast::{Expr, MetaItem, Mutability};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::symbol::Symbol;
 use rustc_span::Span;
-use syntax::ast;
-use syntax::ast::{Expr, MetaItem, Mutability};
-use syntax::ptr::P;
 
 pub fn expand_deriving_rustc_decodable(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/deriving/default.rs b/src/librustc_builtin_macros/deriving/default.rs
index b4f059e94c1..cb85a0b1a10 100644
--- a/src/librustc_builtin_macros/deriving/default.rs
+++ b/src/librustc_builtin_macros/deriving/default.rs
@@ -2,12 +2,12 @@ use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::path_std;
 
+use rustc_ast::ast::{Expr, MetaItem};
+use rustc_ast::ptr::P;
 use rustc_errors::struct_span_err;
 use rustc_expand::base::{Annotatable, DummyResult, ExtCtxt};
 use rustc_span::symbol::{kw, sym};
 use rustc_span::Span;
-use syntax::ast::{Expr, MetaItem};
-use syntax::ptr::P;
 
 pub fn expand_deriving_default(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/deriving/encodable.rs b/src/librustc_builtin_macros/deriving/encodable.rs
index b330f00939f..9073085381a 100644
--- a/src/librustc_builtin_macros/deriving/encodable.rs
+++ b/src/librustc_builtin_macros/deriving/encodable.rs
@@ -89,11 +89,11 @@ use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::pathvec_std;
 
+use rustc_ast::ast::{Expr, ExprKind, MetaItem, Mutability};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::symbol::Symbol;
 use rustc_span::Span;
-use syntax::ast::{Expr, ExprKind, MetaItem, Mutability};
-use syntax::ptr::P;
 
 pub fn expand_deriving_rustc_encodable(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/deriving/generic/mod.rs b/src/librustc_builtin_macros/deriving/generic/mod.rs
index 7f7ee6e0fed..311298c0f40 100644
--- a/src/librustc_builtin_macros/deriving/generic/mod.rs
+++ b/src/librustc_builtin_macros/deriving/generic/mod.rs
@@ -181,16 +181,16 @@ use std::cell::RefCell;
 use std::iter;
 use std::vec;
 
+use rustc_ast::ast::{self, BinOpKind, EnumDef, Expr, Generics, Ident, PatKind};
+use rustc_ast::ast::{GenericArg, GenericParamKind, VariantData};
+use rustc_ast::ptr::P;
+use rustc_ast::util::map_in_place::MapInPlace;
 use rustc_attr as attr;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_session::parse::ParseSess;
 use rustc_span::source_map::respan;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
-use syntax::ast::{self, BinOpKind, EnumDef, Expr, Generics, Ident, PatKind};
-use syntax::ast::{GenericArg, GenericParamKind, VariantData};
-use syntax::ptr::P;
-use syntax::util::map_in_place::MapInPlace;
 
 use ty::{LifetimeBounds, Path, Ptr, PtrTy, Self_, Ty};
 
@@ -339,7 +339,7 @@ fn find_type_parameters(
     ty_param_names: &[ast::Name],
     cx: &ExtCtxt<'_>,
 ) -> Vec<P<ast::Ty>> {
-    use syntax::visit;
+    use rustc_ast::visit;
 
     struct Visitor<'a, 'b> {
         cx: &'a ExtCtxt<'b>,
@@ -689,11 +689,11 @@ impl<'a> TraitDef<'a> {
         attr::mark_used(&attr);
         let opt_trait_ref = Some(trait_ref);
         let unused_qual = {
-            let word = syntax::attr::mk_nested_word_item(Ident::new(
+            let word = rustc_ast::attr::mk_nested_word_item(Ident::new(
                 Symbol::intern("unused_qualifications"),
                 self.span,
             ));
-            let list = syntax::attr::mk_list_item(Ident::new(sym::allow, self.span), vec![word]);
+            let list = rustc_ast::attr::mk_list_item(Ident::new(sym::allow, self.span), vec![word]);
             cx.attribute(list)
         };
 
diff --git a/src/librustc_builtin_macros/deriving/generic/ty.rs b/src/librustc_builtin_macros/deriving/generic/ty.rs
index d2df64cac48..bd54a735311 100644
--- a/src/librustc_builtin_macros/deriving/generic/ty.rs
+++ b/src/librustc_builtin_macros/deriving/generic/ty.rs
@@ -4,12 +4,12 @@
 pub use PtrTy::*;
 pub use Ty::*;
 
+use rustc_ast::ast::{self, Expr, GenericArg, GenericParamKind, Generics, Ident, SelfKind};
+use rustc_ast::ptr::P;
 use rustc_expand::base::ExtCtxt;
 use rustc_span::source_map::{respan, DUMMY_SP};
 use rustc_span::symbol::kw;
 use rustc_span::Span;
-use syntax::ast::{self, Expr, GenericArg, GenericParamKind, Generics, Ident, SelfKind};
-use syntax::ptr::P;
 
 /// The types of pointers
 #[derive(Clone)]
diff --git a/src/librustc_builtin_macros/deriving/hash.rs b/src/librustc_builtin_macros/deriving/hash.rs
index e620711aa2b..8776e7ef507 100644
--- a/src/librustc_builtin_macros/deriving/hash.rs
+++ b/src/librustc_builtin_macros/deriving/hash.rs
@@ -2,11 +2,11 @@ use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::{self, path_std, pathvec_std};
 
+use rustc_ast::ast::{Expr, MetaItem, Mutability};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::ast::{Expr, MetaItem, Mutability};
-use syntax::ptr::P;
 
 pub fn expand_deriving_hash(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/deriving/mod.rs b/src/librustc_builtin_macros/deriving/mod.rs
index 63cd03527e1..5ba9d3800e1 100644
--- a/src/librustc_builtin_macros/deriving/mod.rs
+++ b/src/librustc_builtin_macros/deriving/mod.rs
@@ -1,10 +1,10 @@
 //! The compiler code necessary to implement the `#[derive]` extensions.
 
+use rustc_ast::ast::{self, ItemKind, MetaItem};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{Annotatable, ExtCtxt, MultiItemModifier};
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
-use syntax::ast::{self, ItemKind, MetaItem};
-use syntax::ptr::P;
 
 macro path_local($x:ident) {
     generic::ty::Path::new_local(stringify!($x))
diff --git a/src/librustc_builtin_macros/env.rs b/src/librustc_builtin_macros/env.rs
index 896bb8ca053..fba76f8b496 100644
--- a/src/librustc_builtin_macros/env.rs
+++ b/src/librustc_builtin_macros/env.rs
@@ -3,11 +3,11 @@
 // interface.
 //
 
+use rustc_ast::ast::{self, GenericArg, Ident};
+use rustc_ast::tokenstream::TokenStream;
 use rustc_expand::base::{self, *};
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
-use syntax::ast::{self, GenericArg, Ident};
-use syntax::tokenstream::TokenStream;
 
 use std::env;
 
diff --git a/src/librustc_builtin_macros/format.rs b/src/librustc_builtin_macros/format.rs
index 0684662b2bf..da81347f59f 100644
--- a/src/librustc_builtin_macros/format.rs
+++ b/src/librustc_builtin_macros/format.rs
@@ -3,15 +3,15 @@ use Position::*;
 
 use fmt_macros as parse;
 
+use rustc_ast::ast;
+use rustc_ast::ptr::P;
+use rustc_ast::token;
+use rustc_ast::tokenstream::TokenStream;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::{pluralize, Applicability, DiagnosticBuilder};
 use rustc_expand::base::{self, *};
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{MultiSpan, Span};
-use syntax::ast;
-use syntax::ptr::P;
-use syntax::token;
-use syntax::tokenstream::TokenStream;
 
 use std::borrow::Cow;
 use std::collections::hash_map::Entry;
diff --git a/src/librustc_builtin_macros/global_allocator.rs b/src/librustc_builtin_macros/global_allocator.rs
index 5a0b1a6b885..8de7455a09a 100644
--- a/src/librustc_builtin_macros/global_allocator.rs
+++ b/src/librustc_builtin_macros/global_allocator.rs
@@ -1,12 +1,14 @@
 use crate::util::check_builtin_macro_attribute;
 
+use rustc_ast::ast::{self, Attribute, Expr, FnHeader, FnSig, Generics, Ident, Param};
+use rustc_ast::ast::{ItemKind, Mutability, Stmt, Ty, TyKind, Unsafe};
+use rustc_ast::expand::allocator::{
+    AllocatorKind, AllocatorMethod, AllocatorTy, ALLOCATOR_METHODS,
+};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
-use syntax::ast::{self, Attribute, Expr, FnHeader, FnSig, Generics, Ident, Param};
-use syntax::ast::{ItemKind, Mutability, Stmt, Ty, TyKind, Unsafe};
-use syntax::expand::allocator::{AllocatorKind, AllocatorMethod, AllocatorTy, ALLOCATOR_METHODS};
-use syntax::ptr::P;
 
 pub fn expand(
     ecx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/global_asm.rs b/src/librustc_builtin_macros/global_asm.rs
index 052e62ee9ff..307e7fe7121 100644
--- a/src/librustc_builtin_macros/global_asm.rs
+++ b/src/librustc_builtin_macros/global_asm.rs
@@ -8,15 +8,15 @@
 //! LLVM's `module asm "some assembly here"`. All of LLVM's caveats
 //! therefore apply.
 
+use rustc_ast::ast;
+use rustc_ast::ptr::P;
+use rustc_ast::token;
+use rustc_ast::tokenstream::TokenStream;
 use rustc_errors::DiagnosticBuilder;
 use rustc_expand::base::{self, *};
 use rustc_span::source_map::respan;
 use rustc_span::Span;
 use smallvec::smallvec;
-use syntax::ast;
-use syntax::ptr::P;
-use syntax::token;
-use syntax::tokenstream::TokenStream;
 
 pub fn expand_global_asm<'cx>(
     cx: &'cx mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/lib.rs b/src/librustc_builtin_macros/lib.rs
index c735ba0df3b..9a8b0a87cb7 100644
--- a/src/librustc_builtin_macros/lib.rs
+++ b/src/librustc_builtin_macros/lib.rs
@@ -13,11 +13,11 @@ extern crate proc_macro;
 
 use crate::deriving::*;
 
+use rustc_ast::ast::Ident;
 use rustc_expand::base::{MacroExpanderFn, Resolver, SyntaxExtension, SyntaxExtensionKind};
 use rustc_expand::proc_macro::BangProcMacro;
 use rustc_span::edition::Edition;
 use rustc_span::symbol::sym;
-use syntax::ast::Ident;
 
 mod asm;
 mod assert;
diff --git a/src/librustc_builtin_macros/log_syntax.rs b/src/librustc_builtin_macros/log_syntax.rs
index ac7ba49ba18..ae3a889428a 100644
--- a/src/librustc_builtin_macros/log_syntax.rs
+++ b/src/librustc_builtin_macros/log_syntax.rs
@@ -1,6 +1,6 @@
+use rustc_ast::tokenstream::TokenStream;
 use rustc_ast_pretty::pprust;
 use rustc_expand::base;
-use syntax::tokenstream::TokenStream;
 
 pub fn expand_log_syntax<'cx>(
     _cx: &'cx mut base::ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/proc_macro_harness.rs b/src/librustc_builtin_macros/proc_macro_harness.rs
index b925cad9fdc..0a9b59f0e9a 100644
--- a/src/librustc_builtin_macros/proc_macro_harness.rs
+++ b/src/librustc_builtin_macros/proc_macro_harness.rs
@@ -1,5 +1,10 @@
 use std::mem;
 
+use rustc_ast::ast::{self, Ident, NodeId};
+use rustc_ast::attr;
+use rustc_ast::expand::is_proc_macro_attr;
+use rustc_ast::ptr::P;
+use rustc_ast::visit::{self, Visitor};
 use rustc_ast_pretty::pprust;
 use rustc_expand::base::{ExtCtxt, Resolver};
 use rustc_expand::expand::{AstFragment, ExpansionConfig};
@@ -9,11 +14,6 @@ use rustc_span::symbol::{kw, sym};
 use rustc_span::{Span, DUMMY_SP};
 use smallvec::smallvec;
 use std::cell::RefCell;
-use syntax::ast::{self, Ident, NodeId};
-use syntax::attr;
-use syntax::expand::is_proc_macro_attr;
-use syntax::ptr::P;
-use syntax::visit::{self, Visitor};
 
 struct ProcMacroDerive {
     id: NodeId,
diff --git a/src/librustc_builtin_macros/source_util.rs b/src/librustc_builtin_macros/source_util.rs
index 264223bafbc..5ad72a7443d 100644
--- a/src/librustc_builtin_macros/source_util.rs
+++ b/src/librustc_builtin_macros/source_util.rs
@@ -1,3 +1,7 @@
+use rustc_ast::ast;
+use rustc_ast::ptr::P;
+use rustc_ast::token;
+use rustc_ast::tokenstream::TokenStream;
 use rustc_ast_pretty::pprust;
 use rustc_expand::base::{self, *};
 use rustc_expand::panictry;
@@ -5,10 +9,6 @@ use rustc_parse::{self, new_sub_parser_from_file, parser::Parser, DirectoryOwner
 use rustc_session::lint::builtin::INCOMPLETE_INCLUDE;
 use rustc_span::symbol::Symbol;
 use rustc_span::{self, Pos, Span};
-use syntax::ast;
-use syntax::ptr::P;
-use syntax::token;
-use syntax::tokenstream::TokenStream;
 
 use smallvec::SmallVec;
 
diff --git a/src/librustc_builtin_macros/standard_library_imports.rs b/src/librustc_builtin_macros/standard_library_imports.rs
index 6663eecbf5f..30403f6dc41 100644
--- a/src/librustc_builtin_macros/standard_library_imports.rs
+++ b/src/librustc_builtin_macros/standard_library_imports.rs
@@ -1,3 +1,5 @@
+use rustc_ast::ptr::P;
+use rustc_ast::{ast, attr};
 use rustc_expand::base::{ExtCtxt, Resolver};
 use rustc_expand::expand::ExpansionConfig;
 use rustc_session::parse::ParseSess;
@@ -5,8 +7,6 @@ use rustc_span::edition::Edition;
 use rustc_span::hygiene::AstPass;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::DUMMY_SP;
-use syntax::ptr::P;
-use syntax::{ast, attr};
 
 pub fn inject(
     mut krate: ast::Crate,
diff --git a/src/librustc_builtin_macros/test.rs b/src/librustc_builtin_macros/test.rs
index 8407352f577..7fe65f28532 100644
--- a/src/librustc_builtin_macros/test.rs
+++ b/src/librustc_builtin_macros/test.rs
@@ -2,13 +2,13 @@
 /// Ideally, this code would be in libtest but for efficiency and error messages it lives here.
 use crate::util::check_builtin_macro_attribute;
 
+use rustc_ast::ast;
+use rustc_ast::attr;
 use rustc_ast_pretty::pprust;
 use rustc_expand::base::*;
 use rustc_span::source_map::respan;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
-use syntax::ast;
-use syntax::attr;
 
 use std::iter;
 
diff --git a/src/librustc_builtin_macros/test_harness.rs b/src/librustc_builtin_macros/test_harness.rs
index 4bbab0d2574..51a21702805 100644
--- a/src/librustc_builtin_macros/test_harness.rs
+++ b/src/librustc_builtin_macros/test_harness.rs
@@ -1,6 +1,11 @@
 // Code that generates a test runner to run all the tests in a crate
 
 use log::debug;
+use rustc_ast::ast::{self, Ident};
+use rustc_ast::attr;
+use rustc_ast::entry::{self, EntryPointType};
+use rustc_ast::mut_visit::{ExpectOne, *};
+use rustc_ast::ptr::P;
 use rustc_expand::base::{ExtCtxt, Resolver};
 use rustc_expand::expand::{AstFragment, ExpansionConfig};
 use rustc_feature::Features;
@@ -11,11 +16,6 @@ use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{Span, DUMMY_SP};
 use rustc_target::spec::PanicStrategy;
 use smallvec::{smallvec, SmallVec};
-use syntax::ast::{self, Ident};
-use syntax::attr;
-use syntax::entry::{self, EntryPointType};
-use syntax::mut_visit::{ExpectOne, *};
-use syntax::ptr::P;
 
 use std::{iter, mem};
 
diff --git a/src/librustc_builtin_macros/trace_macros.rs b/src/librustc_builtin_macros/trace_macros.rs
index c0b373f1370..c17f2afe494 100644
--- a/src/librustc_builtin_macros/trace_macros.rs
+++ b/src/librustc_builtin_macros/trace_macros.rs
@@ -1,7 +1,7 @@
+use rustc_ast::tokenstream::{TokenStream, TokenTree};
 use rustc_expand::base::{self, ExtCtxt};
 use rustc_span::symbol::kw;
 use rustc_span::Span;
-use syntax::tokenstream::{TokenStream, TokenTree};
 
 pub fn expand_trace_macros(
     cx: &mut ExtCtxt<'_>,
diff --git a/src/librustc_builtin_macros/util.rs b/src/librustc_builtin_macros/util.rs
index b7d1a5d1d7c..8ef76a8657e 100644
--- a/src/librustc_builtin_macros/util.rs
+++ b/src/librustc_builtin_macros/util.rs
@@ -1,8 +1,8 @@
+use rustc_ast::ast::MetaItem;
 use rustc_expand::base::ExtCtxt;
 use rustc_feature::AttributeTemplate;
 use rustc_parse::validate_attr;
 use rustc_span::Symbol;
-use syntax::ast::MetaItem;
 
 pub fn check_builtin_macro_attribute(ecx: &ExtCtxt<'_>, meta_item: &MetaItem, name: Symbol) {
     // All the built-in macro attributes are "words" at the moment.
diff --git a/src/librustc_codegen_llvm/Cargo.toml b/src/librustc_codegen_llvm/Cargo.toml
index 09a25a0a2fb..0776cb19760 100644
--- a/src/librustc_codegen_llvm/Cargo.toml
+++ b/src/librustc_codegen_llvm/Cargo.toml
@@ -33,5 +33,5 @@ rustc_session = { path = "../librustc_session" }
 rustc_serialize = { path = "../libserialize", package = "serialize" }
 rustc_target = { path = "../librustc_target" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
diff --git a/src/librustc_codegen_llvm/allocator.rs b/src/librustc_codegen_llvm/allocator.rs
index 6dcf49f23fe..821377db0ee 100644
--- a/src/librustc_codegen_llvm/allocator.rs
+++ b/src/librustc_codegen_llvm/allocator.rs
@@ -4,7 +4,7 @@ use crate::attributes;
 use libc::c_uint;
 use rustc::bug;
 use rustc::ty::TyCtxt;
-use syntax::expand::allocator::{AllocatorKind, AllocatorTy, ALLOCATOR_METHODS};
+use rustc_ast::expand::allocator::{AllocatorKind, AllocatorTy, ALLOCATOR_METHODS};
 
 use crate::llvm::{self, False, True};
 use crate::ModuleLlvm;
diff --git a/src/librustc_codegen_llvm/asm.rs b/src/librustc_codegen_llvm/asm.rs
index e816bdeb1c9..8066136c2fe 100644
--- a/src/librustc_codegen_llvm/asm.rs
+++ b/src/librustc_codegen_llvm/asm.rs
@@ -134,7 +134,7 @@ fn inline_asm_call(
     output: &'ll llvm::Type,
     volatile: bool,
     alignstack: bool,
-    dia: ::syntax::ast::AsmDialect,
+    dia: ::rustc_ast::ast::AsmDialect,
 ) -> Option<&'ll Value> {
     let volatile = if volatile { llvm::True } else { llvm::False };
     let alignstack = if alignstack { llvm::True } else { llvm::False };
diff --git a/src/librustc_codegen_llvm/builder.rs b/src/librustc_codegen_llvm/builder.rs
index ab6c55becdb..32604d5601d 100644
--- a/src/librustc_codegen_llvm/builder.rs
+++ b/src/librustc_codegen_llvm/builder.rs
@@ -303,8 +303,8 @@ impl BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         rhs: Self::Value,
     ) -> (Self::Value, Self::Value) {
         use rustc::ty::{Int, Uint};
-        use syntax::ast::IntTy::*;
-        use syntax::ast::UintTy::*;
+        use rustc_ast::ast::IntTy::*;
+        use rustc_ast::ast::UintTy::*;
 
         let new_kind = match ty.kind {
             Int(t @ Isize) => Int(t.normalize(self.tcx.sess.target.ptr_width)),
diff --git a/src/librustc_codegen_llvm/common.rs b/src/librustc_codegen_llvm/common.rs
index 1d6bfb32159..df38eeec00f 100644
--- a/src/librustc_codegen_llvm/common.rs
+++ b/src/librustc_codegen_llvm/common.rs
@@ -18,8 +18,8 @@ use rustc_codegen_ssa::mir::place::PlaceRef;
 
 use libc::{c_char, c_uint};
 
+use rustc_ast::ast::Mutability;
 use rustc_span::symbol::Symbol;
-use syntax::ast::Mutability;
 
 pub use crate::context::CodegenCx;
 
diff --git a/src/librustc_codegen_llvm/debuginfo/gdb.rs b/src/librustc_codegen_llvm/debuginfo/gdb.rs
index eae461a575f..753a4e18faf 100644
--- a/src/librustc_codegen_llvm/debuginfo/gdb.rs
+++ b/src/librustc_codegen_llvm/debuginfo/gdb.rs
@@ -9,8 +9,8 @@ use rustc::bug;
 use rustc::session::config::DebugInfo;
 use rustc_codegen_ssa::traits::*;
 
+use rustc_ast::attr;
 use rustc_span::symbol::sym;
-use syntax::attr;
 
 /// Inserts a side-effect free instruction sequence that makes sure that the
 /// .debug_gdb_scripts global is referenced, so it isn't removed by the linker.
diff --git a/src/librustc_codegen_llvm/debuginfo/metadata.rs b/src/librustc_codegen_llvm/debuginfo/metadata.rs
index d1f70ad43bd..6ed3153963f 100644
--- a/src/librustc_codegen_llvm/debuginfo/metadata.rs
+++ b/src/librustc_codegen_llvm/debuginfo/metadata.rs
@@ -32,6 +32,7 @@ use rustc::ty::subst::{GenericArgKind, SubstsRef};
 use rustc::ty::Instance;
 use rustc::ty::{self, AdtKind, ParamEnv, Ty, TyCtxt};
 use rustc::{bug, span_bug};
+use rustc_ast::ast;
 use rustc_codegen_ssa::traits::*;
 use rustc_data_structures::const_cstr;
 use rustc_data_structures::fingerprint::Fingerprint;
@@ -45,7 +46,6 @@ use rustc_index::vec::{Idx, IndexVec};
 use rustc_span::symbol::{Interner, Symbol};
 use rustc_span::{self, FileName, Span};
 use rustc_target::abi::HasDataLayout;
-use syntax::ast;
 
 use libc::{c_longlong, c_uint};
 use std::collections::hash_map::Entry;
diff --git a/src/librustc_codegen_llvm/debuginfo/mod.rs b/src/librustc_codegen_llvm/debuginfo/mod.rs
index 22effb102fd..6515d5e3bec 100644
--- a/src/librustc_codegen_llvm/debuginfo/mod.rs
+++ b/src/librustc_codegen_llvm/debuginfo/mod.rs
@@ -35,11 +35,11 @@ use std::cell::RefCell;
 use std::ffi::CString;
 
 use rustc::ty::layout::{self, HasTyCtxt, LayoutOf, Size};
+use rustc_ast::ast;
 use rustc_codegen_ssa::traits::*;
 use rustc_span::symbol::Symbol;
 use rustc_span::{self, BytePos, Span};
 use smallvec::SmallVec;
-use syntax::ast;
 
 mod create_scope_map;
 pub mod gdb;
diff --git a/src/librustc_codegen_llvm/intrinsic.rs b/src/librustc_codegen_llvm/intrinsic.rs
index 3d1e72e1c73..1ae9d2a6841 100644
--- a/src/librustc_codegen_llvm/intrinsic.rs
+++ b/src/librustc_codegen_llvm/intrinsic.rs
@@ -10,6 +10,7 @@ use crate::value::Value;
 use rustc::ty::layout::{self, FnAbiExt, HasTyCtxt, LayoutOf, Primitive};
 use rustc::ty::{self, Ty};
 use rustc::{bug, span_bug};
+use rustc_ast::ast;
 use rustc_codegen_ssa::base::{compare_simd_types, to_immediate, wants_msvc_seh};
 use rustc_codegen_ssa::common::{IntPredicate, TypeKind};
 use rustc_codegen_ssa::glue;
@@ -18,7 +19,6 @@ use rustc_codegen_ssa::mir::place::PlaceRef;
 use rustc_codegen_ssa::MemFlags;
 use rustc_hir as hir;
 use rustc_target::abi::HasDataLayout;
-use syntax::ast;
 
 use rustc_codegen_ssa::common::span_invalid_monomorphization_error;
 use rustc_codegen_ssa::traits::*;
diff --git a/src/librustc_codegen_llvm/lib.rs b/src/librustc_codegen_llvm/lib.rs
index b1085ba1703..f3265754574 100644
--- a/src/librustc_codegen_llvm/lib.rs
+++ b/src/librustc_codegen_llvm/lib.rs
@@ -19,6 +19,7 @@ use rustc_span::symbol::Symbol;
 
 pub use llvm_util::target_features;
 use rustc::dep_graph::WorkProduct;
+use rustc_ast::expand::allocator::AllocatorKind;
 use rustc_codegen_ssa::back::lto::{LtoModuleCodegen, SerializedModule, ThinModule};
 use rustc_codegen_ssa::back::write::{CodegenContext, FatLTOInput, ModuleConfig};
 use rustc_codegen_ssa::traits::*;
@@ -28,7 +29,6 @@ use std::any::Any;
 use std::ffi::CStr;
 use std::fs;
 use std::sync::Arc;
-use syntax::expand::allocator::AllocatorKind;
 
 use rustc::dep_graph::DepGraph;
 use rustc::middle::cstore::{EncodedMetadata, MetadataLoaderDyn};
diff --git a/src/librustc_codegen_llvm/llvm/ffi.rs b/src/librustc_codegen_llvm/llvm/ffi.rs
index 808094eca91..f56647044e0 100644
--- a/src/librustc_codegen_llvm/llvm/ffi.rs
+++ b/src/librustc_codegen_llvm/llvm/ffi.rs
@@ -381,10 +381,10 @@ pub enum AsmDialect {
 }
 
 impl AsmDialect {
-    pub fn from_generic(asm: syntax::ast::AsmDialect) -> Self {
+    pub fn from_generic(asm: rustc_ast::ast::AsmDialect) -> Self {
         match asm {
-            syntax::ast::AsmDialect::Att => AsmDialect::Att,
-            syntax::ast::AsmDialect::Intel => AsmDialect::Intel,
+            rustc_ast::ast::AsmDialect::Att => AsmDialect::Att,
+            rustc_ast::ast::AsmDialect::Intel => AsmDialect::Intel,
         }
     }
 }
diff --git a/src/librustc_codegen_llvm/type_.rs b/src/librustc_codegen_llvm/type_.rs
index 628b6fe39e6..aacaf130f9a 100644
--- a/src/librustc_codegen_llvm/type_.rs
+++ b/src/librustc_codegen_llvm/type_.rs
@@ -12,10 +12,10 @@ use crate::common;
 use crate::type_of::LayoutLlvmExt;
 use rustc::ty::layout::{self, Align, Size, TyLayout};
 use rustc::ty::Ty;
+use rustc_ast::ast;
 use rustc_codegen_ssa::common::TypeKind;
 use rustc_data_structures::small_c_str::SmallCStr;
 use rustc_target::abi::call::{CastTarget, FnAbi, Reg};
-use syntax::ast;
 
 use std::fmt;
 use std::ptr;
diff --git a/src/librustc_codegen_ssa/Cargo.toml b/src/librustc_codegen_ssa/Cargo.toml
index f70e4d87397..3181d568b01 100644
--- a/src/librustc_codegen_ssa/Cargo.toml
+++ b/src/librustc_codegen_ssa/Cargo.toml
@@ -20,7 +20,7 @@ jobserver = "0.1.11"
 tempfile = "3.1"
 
 rustc_serialize = { path = "../libserialize", package = "serialize" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
 rustc = { path = "../librustc" }
 rustc_apfloat = { path = "../librustc_apfloat" }
diff --git a/src/librustc_codegen_ssa/back/symbol_export.rs b/src/librustc_codegen_ssa/back/symbol_export.rs
index a6cd0c09684..3fe256ce25b 100644
--- a/src/librustc_codegen_ssa/back/symbol_export.rs
+++ b/src/librustc_codegen_ssa/back/symbol_export.rs
@@ -8,6 +8,7 @@ use rustc::ty::query::Providers;
 use rustc::ty::subst::{GenericArgKind, SubstsRef};
 use rustc::ty::Instance;
 use rustc::ty::{SymbolName, TyCtxt};
+use rustc_ast::expand::allocator::ALLOCATOR_METHODS;
 use rustc_codegen_utils::symbol_names;
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::FxHashMap;
@@ -15,7 +16,6 @@ use rustc_hir as hir;
 use rustc_hir::def_id::{CrateNum, DefId, DefIdMap, CRATE_DEF_INDEX, LOCAL_CRATE};
 use rustc_hir::Node;
 use rustc_index::vec::IndexVec;
-use syntax::expand::allocator::ALLOCATOR_METHODS;
 
 pub fn threshold(tcx: TyCtxt<'_>) -> SymbolExportLevel {
     crates_export_threshold(&tcx.sess.crate_types.borrow())
diff --git a/src/librustc_codegen_ssa/back/write.rs b/src/librustc_codegen_ssa/back/write.rs
index 2cdbb204696..76728e98406 100644
--- a/src/librustc_codegen_ssa/back/write.rs
+++ b/src/librustc_codegen_ssa/back/write.rs
@@ -19,6 +19,7 @@ use rustc::session::config::{
 };
 use rustc::session::Session;
 use rustc::ty::TyCtxt;
+use rustc_ast::attr;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::profiling::SelfProfilerRef;
 use rustc_data_structures::profiling::TimingGuard;
@@ -37,7 +38,6 @@ use rustc_span::hygiene::ExpnId;
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_target::spec::MergeFunctions;
-use syntax::attr;
 
 use std::any::Any;
 use std::fs;
diff --git a/src/librustc_codegen_ssa/traits/backend.rs b/src/librustc_codegen_ssa/traits/backend.rs
index 7b22961cd46..5535841156a 100644
--- a/src/librustc_codegen_ssa/traits/backend.rs
+++ b/src/librustc_codegen_ssa/traits/backend.rs
@@ -7,9 +7,9 @@ use rustc::session::{config, Session};
 use rustc::ty::layout::{HasTyCtxt, LayoutOf, TyLayout};
 use rustc::ty::Ty;
 use rustc::ty::TyCtxt;
+use rustc_ast::expand::allocator::AllocatorKind;
 use rustc_codegen_utils::codegen_backend::CodegenBackend;
 use rustc_span::symbol::Symbol;
-use syntax::expand::allocator::AllocatorKind;
 
 use std::sync::Arc;
 
diff --git a/src/librustc_codegen_ssa/traits/debuginfo.rs b/src/librustc_codegen_ssa/traits/debuginfo.rs
index 3688ae51b39..14c5a1b8ee9 100644
--- a/src/librustc_codegen_ssa/traits/debuginfo.rs
+++ b/src/librustc_codegen_ssa/traits/debuginfo.rs
@@ -3,10 +3,10 @@ use crate::mir::debuginfo::{FunctionDebugContext, VariableKind};
 use rustc::mir;
 use rustc::ty::layout::Size;
 use rustc::ty::{Instance, Ty};
+use rustc_ast::ast::Name;
 use rustc_hir::def_id::CrateNum;
 use rustc_span::{SourceFile, Span};
 use rustc_target::abi::call::FnAbi;
-use syntax::ast::Name;
 
 pub trait DebugInfoMethods<'tcx>: BackendTypes {
     fn create_vtable_metadata(&self, ty: Ty<'tcx>, vtable: Self::Value);
diff --git a/src/librustc_codegen_utils/Cargo.toml b/src/librustc_codegen_utils/Cargo.toml
index 45aabd5f452..b5533a8307c 100644
--- a/src/librustc_codegen_utils/Cargo.toml
+++ b/src/librustc_codegen_utils/Cargo.toml
@@ -14,7 +14,7 @@ log = "0.4"
 punycode = "0.4.0"
 rustc-demangle = "0.1.16"
 
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
 rustc = { path = "../librustc" }
 rustc_hir = { path = "../librustc_hir" }
diff --git a/src/librustc_codegen_utils/link.rs b/src/librustc_codegen_utils/link.rs
index 92cbc42388d..524fb0a59c2 100644
--- a/src/librustc_codegen_utils/link.rs
+++ b/src/librustc_codegen_utils/link.rs
@@ -1,9 +1,9 @@
 use rustc::session::config::{self, Input, OutputFilenames, OutputType};
 use rustc::session::Session;
+use rustc_ast::{ast, attr};
 use rustc_span::symbol::sym;
 use rustc_span::Span;
 use std::path::{Path, PathBuf};
-use syntax::{ast, attr};
 
 pub fn out_filename(
     sess: &Session,
diff --git a/src/librustc_codegen_utils/symbol_names/v0.rs b/src/librustc_codegen_utils/symbol_names/v0.rs
index ff4e128e190..ce6d0d9dc5b 100644
--- a/src/librustc_codegen_utils/symbol_names/v0.rs
+++ b/src/librustc_codegen_utils/symbol_names/v0.rs
@@ -2,12 +2,12 @@ use rustc::hir::map::{DefPathData, DisambiguatedDefPathData};
 use rustc::ty::print::{Print, Printer};
 use rustc::ty::subst::{GenericArg, GenericArgKind, Subst};
 use rustc::ty::{self, Instance, Ty, TyCtxt, TypeFoldable};
+use rustc_ast::ast::{FloatTy, IntTy, UintTy};
 use rustc_data_structures::base_n;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 use rustc_hir::def_id::{CrateNum, DefId};
 use rustc_target::spec::abi::Abi;
-use syntax::ast::{FloatTy, IntTy, UintTy};
 
 use std::fmt::Write;
 use std::ops::Range;
diff --git a/src/librustc_driver/Cargo.toml b/src/librustc_driver/Cargo.toml
index 2e3b321a524..26f1741153c 100644
--- a/src/librustc_driver/Cargo.toml
+++ b/src/librustc_driver/Cargo.toml
@@ -31,7 +31,7 @@ rustc_codegen_utils = { path = "../librustc_codegen_utils" }
 rustc_error_codes = { path = "../librustc_error_codes" }
 rustc_interface = { path = "../librustc_interface" }
 rustc_serialize = { path = "../libserialize", package = "serialize" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
 
 [target.'cfg(windows)'.dependencies]
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index b00b1656bf7..9a94349e5fd 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -55,10 +55,10 @@ use std::process::{self, Command, Stdio};
 use std::str;
 use std::time::Instant;
 
+use rustc_ast::ast;
 use rustc_span::source_map::FileLoader;
 use rustc_span::symbol::sym;
 use rustc_span::FileName;
-use syntax::ast;
 
 mod args;
 pub mod pretty;
diff --git a/src/librustc_driver/pretty.rs b/src/librustc_driver/pretty.rs
index 236a7243998..ca129ac5984 100644
--- a/src/librustc_driver/pretty.rs
+++ b/src/librustc_driver/pretty.rs
@@ -5,13 +5,13 @@ use rustc::session::config::{Input, PpMode, PpSourceMode};
 use rustc::session::Session;
 use rustc::ty::{self, TyCtxt};
 use rustc::util::common::ErrorReported;
+use rustc_ast::ast;
 use rustc_ast_pretty::pprust;
 use rustc_hir as hir;
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_hir::print as pprust_hir;
 use rustc_mir::util::{write_mir_graphviz, write_mir_pretty};
 use rustc_span::FileName;
-use syntax::ast;
 
 use std::cell::Cell;
 use std::fs::File;
diff --git a/src/librustc_expand/Cargo.toml b/src/librustc_expand/Cargo.toml
index 4da90ba229d..3cb79030771 100644
--- a/src/librustc_expand/Cargo.toml
+++ b/src/librustc_expand/Cargo.toml
@@ -24,4 +24,4 @@ rustc_lexer = { path = "../librustc_lexer" }
 rustc_parse = { path = "../librustc_parse" }
 rustc_session = { path = "../librustc_session" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
diff --git a/src/librustc_expand/base.rs b/src/librustc_expand/base.rs
index a5614f900b6..9258b59f79b 100644
--- a/src/librustc_expand/base.rs
+++ b/src/librustc_expand/base.rs
@@ -1,5 +1,11 @@
 use crate::expand::{self, AstFragment, Invocation};
 
+use rustc_ast::ast::{self, Attribute, Name, NodeId, PatKind};
+use rustc_ast::mut_visit::{self, MutVisitor};
+use rustc_ast::ptr::P;
+use rustc_ast::token;
+use rustc_ast::tokenstream::{self, TokenStream};
+use rustc_ast::visit::{AssocCtxt, Visitor};
 use rustc_attr::{self as attr, Deprecation, HasAttrs, Stability};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::{self, Lrc};
@@ -12,12 +18,6 @@ use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{FileName, MultiSpan, Span, DUMMY_SP};
 use smallvec::{smallvec, SmallVec};
-use syntax::ast::{self, Attribute, Name, NodeId, PatKind};
-use syntax::mut_visit::{self, MutVisitor};
-use syntax::ptr::P;
-use syntax::token;
-use syntax::tokenstream::{self, TokenStream};
-use syntax::visit::{AssocCtxt, Visitor};
 
 use std::default::Default;
 use std::iter;
diff --git a/src/librustc_expand/build.rs b/src/librustc_expand/build.rs
index bd6823cd4e2..48ceaf5fccd 100644
--- a/src/librustc_expand/build.rs
+++ b/src/librustc_expand/build.rs
@@ -1,10 +1,10 @@
 use crate::base::ExtCtxt;
 
+use rustc_ast::ast::{self, AttrVec, BlockCheckMode, Expr, Ident, PatKind, UnOp};
+use rustc_ast::attr;
+use rustc_ast::ptr::P;
 use rustc_span::source_map::{respan, Spanned};
 use rustc_span::symbol::{kw, sym, Symbol};
-use syntax::ast::{self, AttrVec, BlockCheckMode, Expr, Ident, PatKind, UnOp};
-use syntax::attr;
-use syntax::ptr::P;
 
 use rustc_span::Span;
 
diff --git a/src/librustc_expand/expand.rs b/src/librustc_expand/expand.rs
index dff243a51b3..a2c512fda91 100644
--- a/src/librustc_expand/expand.rs
+++ b/src/librustc_expand/expand.rs
@@ -5,6 +5,14 @@ use crate::mbe::macro_rules::annotate_err_with_kind;
 use crate::placeholders::{placeholder, PlaceholderExpander};
 use crate::proc_macro::collect_derives;
 
+use rustc_ast::ast::{self, AttrItem, Block, Ident, LitKind, NodeId, PatKind, Path};
+use rustc_ast::ast::{ItemKind, MacArgs, MacStmtStyle, StmtKind};
+use rustc_ast::mut_visit::*;
+use rustc_ast::ptr::P;
+use rustc_ast::token;
+use rustc_ast::tokenstream::{TokenStream, TokenTree};
+use rustc_ast::util::map_in_place::MapInPlace;
+use rustc_ast::visit::{self, AssocCtxt, Visitor};
 use rustc_ast_pretty::pprust;
 use rustc_attr::{self as attr, is_builtin_attr, HasAttrs};
 use rustc_data_structures::sync::Lrc;
@@ -20,14 +28,6 @@ use rustc_session::parse::{feature_err, ParseSess};
 use rustc_span::source_map::respan;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{FileName, Span, DUMMY_SP};
-use syntax::ast::{self, AttrItem, Block, Ident, LitKind, NodeId, PatKind, Path};
-use syntax::ast::{ItemKind, MacArgs, MacStmtStyle, StmtKind};
-use syntax::mut_visit::*;
-use syntax::ptr::P;
-use syntax::token;
-use syntax::tokenstream::{TokenStream, TokenTree};
-use syntax::util::map_in_place::MapInPlace;
-use syntax::visit::{self, AssocCtxt, Visitor};
 
 use smallvec::{smallvec, SmallVec};
 use std::io::ErrorKind;
diff --git a/src/librustc_expand/mbe.rs b/src/librustc_expand/mbe.rs
index fe207a4c876..57957a1fa8b 100644
--- a/src/librustc_expand/mbe.rs
+++ b/src/librustc_expand/mbe.rs
@@ -9,9 +9,9 @@ crate mod macro_rules;
 crate mod quoted;
 crate mod transcribe;
 
-use syntax::ast;
-use syntax::token::{self, Token, TokenKind};
-use syntax::tokenstream::DelimSpan;
+use rustc_ast::ast;
+use rustc_ast::token::{self, Token, TokenKind};
+use rustc_ast::tokenstream::DelimSpan;
 
 use rustc_span::Span;
 
diff --git a/src/librustc_expand/mbe/macro_check.rs b/src/librustc_expand/mbe/macro_check.rs
index 10cdceefdf5..6eb834beac6 100644
--- a/src/librustc_expand/mbe/macro_check.rs
+++ b/src/librustc_expand/mbe/macro_check.rs
@@ -106,13 +106,13 @@
 //! bound.
 use crate::mbe::{KleeneToken, TokenTree};
 
+use rustc_ast::ast::NodeId;
+use rustc_ast::token::{DelimToken, Token, TokenKind};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_session::lint::builtin::META_VARIABLE_MISUSE;
 use rustc_session::parse::ParseSess;
 use rustc_span::symbol::kw;
 use rustc_span::{symbol::Ident, MultiSpan, Span};
-use syntax::ast::NodeId;
-use syntax::token::{DelimToken, Token, TokenKind};
 
 use smallvec::SmallVec;
 
diff --git a/src/librustc_expand/mbe/macro_parser.rs b/src/librustc_expand/mbe/macro_parser.rs
index 2a53d600c5b..d2a5c54aae4 100644
--- a/src/librustc_expand/mbe/macro_parser.rs
+++ b/src/librustc_expand/mbe/macro_parser.rs
@@ -76,13 +76,13 @@ use TokenTreeOrTokenTreeSlice::*;
 
 use crate::mbe::{self, TokenTree};
 
+use rustc_ast::ast::{Ident, Name};
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, DocComment, Nonterminal, Token};
 use rustc_ast_pretty::pprust;
 use rustc_parse::parser::{FollowedByType, Parser, PathStyle};
 use rustc_session::parse::ParseSess;
 use rustc_span::symbol::{kw, sym, Symbol};
-use syntax::ast::{Ident, Name};
-use syntax::ptr::P;
-use syntax::token::{self, DocComment, Nonterminal, Token};
 
 use rustc_errors::{FatalError, PResult};
 use rustc_span::Span;
diff --git a/src/librustc_expand/mbe/macro_rules.rs b/src/librustc_expand/mbe/macro_rules.rs
index 52e581e30f5..02f2a386b33 100644
--- a/src/librustc_expand/mbe/macro_rules.rs
+++ b/src/librustc_expand/mbe/macro_rules.rs
@@ -8,6 +8,9 @@ use crate::mbe::macro_parser::{Error, Failure, Success};
 use crate::mbe::macro_parser::{MatchedNonterminal, MatchedSeq};
 use crate::mbe::transcribe::transcribe;
 
+use rustc_ast::ast;
+use rustc_ast::token::{self, NtTT, Token, TokenKind::*};
+use rustc_ast::tokenstream::{DelimSpan, TokenStream};
 use rustc_ast_pretty::pprust;
 use rustc_attr::{self as attr, TransparencyError};
 use rustc_data_structures::fx::FxHashMap;
@@ -21,9 +24,6 @@ use rustc_span::edition::Edition;
 use rustc_span::hygiene::Transparency;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
-use syntax::ast;
-use syntax::token::{self, NtTT, Token, TokenKind::*};
-use syntax::tokenstream::{DelimSpan, TokenStream};
 
 use log::debug;
 use std::borrow::Cow;
diff --git a/src/librustc_expand/mbe/quoted.rs b/src/librustc_expand/mbe/quoted.rs
index 809bbe47a6e..b19fae65597 100644
--- a/src/librustc_expand/mbe/quoted.rs
+++ b/src/librustc_expand/mbe/quoted.rs
@@ -1,12 +1,12 @@
 use crate::mbe::macro_parser;
 use crate::mbe::{Delimited, KleeneOp, KleeneToken, SequenceRepetition, TokenTree};
 
+use rustc_ast::ast;
+use rustc_ast::token::{self, Token};
+use rustc_ast::tokenstream;
 use rustc_ast_pretty::pprust;
 use rustc_session::parse::ParseSess;
 use rustc_span::symbol::kw;
-use syntax::ast;
-use syntax::token::{self, Token};
-use syntax::tokenstream;
 
 use rustc_span::Span;
 
diff --git a/src/librustc_expand/mbe/transcribe.rs b/src/librustc_expand/mbe/transcribe.rs
index 9e6a2c4f8f5..80bf02b1366 100644
--- a/src/librustc_expand/mbe/transcribe.rs
+++ b/src/librustc_expand/mbe/transcribe.rs
@@ -2,15 +2,15 @@ use crate::base::ExtCtxt;
 use crate::mbe;
 use crate::mbe::macro_parser::{MatchedNonterminal, MatchedSeq, NamedMatch};
 
+use rustc_ast::ast::{Ident, Mac};
+use rustc_ast::mut_visit::{self, MutVisitor};
+use rustc_ast::token::{self, NtTT, Token};
+use rustc_ast::tokenstream::{DelimSpan, TokenStream, TokenTree, TreeAndJoint};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::pluralize;
 use rustc_span::hygiene::{ExpnId, Transparency};
 use rustc_span::Span;
-use syntax::ast::{Ident, Mac};
-use syntax::mut_visit::{self, MutVisitor};
-use syntax::token::{self, NtTT, Token};
-use syntax::tokenstream::{DelimSpan, TokenStream, TokenTree, TreeAndJoint};
 
 use smallvec::{smallvec, SmallVec};
 use std::mem;
diff --git a/src/librustc_expand/mut_visit/tests.rs b/src/librustc_expand/mut_visit/tests.rs
index 49b9a1b1025..4c947d8fa2b 100644
--- a/src/librustc_expand/mut_visit/tests.rs
+++ b/src/librustc_expand/mut_visit/tests.rs
@@ -1,9 +1,9 @@
 use crate::tests::{matches_codepattern, string_to_crate};
 
+use rustc_ast::ast::{self, Ident};
+use rustc_ast::mut_visit::{self, MutVisitor};
+use rustc_ast::with_default_globals;
 use rustc_ast_pretty::pprust;
-use syntax::ast::{self, Ident};
-use syntax::mut_visit::{self, MutVisitor};
-use syntax::with_default_globals;
 
 // This version doesn't care about getting comments or doc-strings in.
 fn fake_print_crate(s: &mut pprust::State<'_>, krate: &ast::Crate) {
diff --git a/src/librustc_expand/parse/lexer/tests.rs b/src/librustc_expand/parse/lexer/tests.rs
index c486839dad5..2cb6267e0f6 100644
--- a/src/librustc_expand/parse/lexer/tests.rs
+++ b/src/librustc_expand/parse/lexer/tests.rs
@@ -1,3 +1,6 @@
+use rustc_ast::token::{self, Token, TokenKind};
+use rustc_ast::util::comments::is_doc_comment;
+use rustc_ast::with_default_globals;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::{emitter::EmitterWriter, Handler};
 use rustc_parse::lexer::StringReader;
@@ -5,9 +8,6 @@ use rustc_session::parse::ParseSess;
 use rustc_span::source_map::{FilePathMapping, SourceMap};
 use rustc_span::symbol::Symbol;
 use rustc_span::{BytePos, Span};
-use syntax::token::{self, Token, TokenKind};
-use syntax::util::comments::is_doc_comment;
-use syntax::with_default_globals;
 
 use std::io;
 use std::path::PathBuf;
diff --git a/src/librustc_expand/parse/tests.rs b/src/librustc_expand/parse/tests.rs
index 4713c8dcd9a..55e815bd4a4 100644
--- a/src/librustc_expand/parse/tests.rs
+++ b/src/librustc_expand/parse/tests.rs
@@ -1,5 +1,11 @@
 use crate::tests::{matches_codepattern, string_to_stream, with_error_checking_parse};
 
+use rustc_ast::ast::{self, Name, PatKind};
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, Token};
+use rustc_ast::tokenstream::{DelimSpan, TokenStream, TokenTree};
+use rustc_ast::visit;
+use rustc_ast::with_default_globals;
 use rustc_ast_pretty::pprust::item_to_string;
 use rustc_errors::PResult;
 use rustc_parse::new_parser_from_source_str;
@@ -7,12 +13,6 @@ use rustc_session::parse::ParseSess;
 use rustc_span::source_map::FilePathMapping;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::{BytePos, FileName, Pos, Span};
-use syntax::ast::{self, Name, PatKind};
-use syntax::ptr::P;
-use syntax::token::{self, Token};
-use syntax::tokenstream::{DelimSpan, TokenStream, TokenTree};
-use syntax::visit;
-use syntax::with_default_globals;
 
 use std::path::PathBuf;
 
diff --git a/src/librustc_expand/placeholders.rs b/src/librustc_expand/placeholders.rs
index c323af4336a..cd4f0a61d42 100644
--- a/src/librustc_expand/placeholders.rs
+++ b/src/librustc_expand/placeholders.rs
@@ -1,10 +1,10 @@
 use crate::base::ExtCtxt;
 use crate::expand::{AstFragment, AstFragmentKind};
 
+use rustc_ast::ast;
+use rustc_ast::mut_visit::*;
+use rustc_ast::ptr::P;
 use rustc_span::source_map::{dummy_spanned, DUMMY_SP};
-use syntax::ast;
-use syntax::mut_visit::*;
-use syntax::ptr::P;
 
 use smallvec::{smallvec, SmallVec};
 
diff --git a/src/librustc_expand/proc_macro.rs b/src/librustc_expand/proc_macro.rs
index cb6249e9369..84a546345bb 100644
--- a/src/librustc_expand/proc_macro.rs
+++ b/src/librustc_expand/proc_macro.rs
@@ -1,13 +1,13 @@
 use crate::base::{self, *};
 use crate::proc_macro_server;
 
+use rustc_ast::ast::{self, ItemKind, MetaItemKind, NestedMetaItem};
+use rustc_ast::token;
+use rustc_ast::tokenstream::{self, TokenStream};
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::{Applicability, FatalError};
 use rustc_span::symbol::sym;
 use rustc_span::{Span, DUMMY_SP};
-use syntax::ast::{self, ItemKind, MetaItemKind, NestedMetaItem};
-use syntax::token;
-use syntax::tokenstream::{self, TokenStream};
 
 const EXEC_STRATEGY: pm::bridge::server::SameThread = pm::bridge::server::SameThread;
 
diff --git a/src/librustc_expand/proc_macro_server.rs b/src/librustc_expand/proc_macro_server.rs
index ce4e262068c..5f21ff503d5 100644
--- a/src/librustc_expand/proc_macro_server.rs
+++ b/src/librustc_expand/proc_macro_server.rs
@@ -1,5 +1,9 @@
 use crate::base::ExtCtxt;
 
+use rustc_ast::ast;
+use rustc_ast::token;
+use rustc_ast::tokenstream::{self, DelimSpan, IsJoint::*, TokenStream, TreeAndJoint};
+use rustc_ast::util::comments;
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::Diagnostic;
@@ -8,10 +12,6 @@ use rustc_parse::{nt_to_tokenstream, parse_stream_from_source_str};
 use rustc_session::parse::ParseSess;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::{BytePos, FileName, MultiSpan, Pos, SourceFile, Span};
-use syntax::ast;
-use syntax::token;
-use syntax::tokenstream::{self, DelimSpan, IsJoint::*, TokenStream, TreeAndJoint};
-use syntax::util::comments;
 
 use pm::bridge::{server, TokenTree};
 use pm::{Delimiter, Level, LineColumn, Spacing};
@@ -54,7 +54,7 @@ impl FromInternal<(TreeAndJoint, &'_ ParseSess, &'_ mut Vec<Self>)>
     fn from_internal(
         ((tree, is_joint), sess, stack): (TreeAndJoint, &ParseSess, &mut Vec<Self>),
     ) -> Self {
-        use syntax::token::*;
+        use rustc_ast::token::*;
 
         let joint = is_joint == Joint;
         let Token { kind, span } = match tree {
@@ -191,7 +191,7 @@ impl FromInternal<(TreeAndJoint, &'_ ParseSess, &'_ mut Vec<Self>)>
 
 impl ToInternal<TokenStream> for TokenTree<Group, Punct, Ident, Literal> {
     fn to_internal(self) -> TokenStream {
-        use syntax::token::*;
+        use rustc_ast::token::*;
 
         let (ch, joint, span) = match self {
             TokenTree::Punct(Punct { ch, joint, span }) => (ch, joint, span),
diff --git a/src/librustc_expand/tests.rs b/src/librustc_expand/tests.rs
index 4ed60465f24..fbc49ddd562 100644
--- a/src/librustc_expand/tests.rs
+++ b/src/librustc_expand/tests.rs
@@ -1,10 +1,10 @@
+use rustc_ast::ast;
+use rustc_ast::tokenstream::TokenStream;
+use rustc_ast::with_default_globals;
 use rustc_parse::{new_parser_from_source_str, parser::Parser, source_file_to_stream};
 use rustc_session::parse::ParseSess;
 use rustc_span::source_map::{FilePathMapping, SourceMap};
 use rustc_span::{BytePos, MultiSpan, Span};
-use syntax::ast;
-use syntax::tokenstream::TokenStream;
-use syntax::with_default_globals;
 
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::emitter::EmitterWriter;
diff --git a/src/librustc_expand/tokenstream/tests.rs b/src/librustc_expand/tokenstream/tests.rs
index 287c168f76a..db329f22d14 100644
--- a/src/librustc_expand/tokenstream/tests.rs
+++ b/src/librustc_expand/tokenstream/tests.rs
@@ -1,11 +1,11 @@
 use crate::tests::string_to_stream;
 
+use rustc_ast::ast::Name;
+use rustc_ast::token;
+use rustc_ast::tokenstream::{TokenStream, TokenStreamBuilder, TokenTree};
+use rustc_ast::with_default_globals;
 use rustc_span::{BytePos, Span};
 use smallvec::smallvec;
-use syntax::ast::Name;
-use syntax::token;
-use syntax::tokenstream::{TokenStream, TokenStreamBuilder, TokenTree};
-use syntax::with_default_globals;
 
 fn string_to_ts(string: &str) -> TokenStream {
     string_to_stream(string.to_owned())
diff --git a/src/librustc_hir/Cargo.toml b/src/librustc_hir/Cargo.toml
index e4c1beb5016..872d114fb18 100644
--- a/src/librustc_hir/Cargo.toml
+++ b/src/librustc_hir/Cargo.toml
@@ -18,6 +18,6 @@ rustc_index = { path = "../librustc_index" }
 rustc_span = { path = "../librustc_span" }
 rustc_errors = { path = "../librustc_errors" }
 rustc_serialize = { path = "../libserialize", package = "serialize" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 lazy_static = "1"
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
diff --git a/src/librustc_hir/def.rs b/src/librustc_hir/def.rs
index 83e30d85c5a..595543eaf53 100644
--- a/src/librustc_hir/def.rs
+++ b/src/librustc_hir/def.rs
@@ -1,10 +1,10 @@
 use crate::def_id::{DefId, CRATE_DEF_INDEX, LOCAL_CRATE};
 use crate::hir;
 
+use rustc_ast::ast;
+use rustc_ast::ast::NodeId;
 use rustc_macros::HashStable_Generic;
 use rustc_span::hygiene::MacroKind;
-use syntax::ast;
-use syntax::ast::NodeId;
 
 use std::fmt::Debug;
 
diff --git a/src/librustc_hir/hir.rs b/src/librustc_hir/hir.rs
index 6cbd8400783..1a74b50b57e 100644
--- a/src/librustc_hir/hir.rs
+++ b/src/librustc_hir/hir.rs
@@ -8,6 +8,13 @@ crate use BlockCheckMode::*;
 crate use FnRetTy::*;
 crate use UnsafeSource::*;
 
+use rustc_ast::ast::{self, AsmDialect, CrateSugar, Ident, Name};
+use rustc_ast::ast::{AttrVec, Attribute, FloatTy, IntTy, Label, LitKind, StrStyle, UintTy};
+pub use rustc_ast::ast::{BorrowKind, ImplPolarity, IsAuto};
+pub use rustc_ast::ast::{CaptureBy, Movability, Mutability};
+use rustc_ast::node_id::NodeMap;
+use rustc_ast::tokenstream::TokenStream;
+use rustc_ast::util::parser::ExprPrecedence;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::sync::{par_for_each_in, Send, Sync};
 use rustc_errors::FatalError;
@@ -16,13 +23,6 @@ use rustc_span::source_map::{SourceMap, Spanned};
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::{MultiSpan, Span, DUMMY_SP};
 use rustc_target::spec::abi::Abi;
-use syntax::ast::{self, AsmDialect, CrateSugar, Ident, Name};
-use syntax::ast::{AttrVec, Attribute, FloatTy, IntTy, Label, LitKind, StrStyle, UintTy};
-pub use syntax::ast::{BorrowKind, ImplPolarity, IsAuto};
-pub use syntax::ast::{CaptureBy, Movability, Mutability};
-use syntax::node_id::NodeMap;
-use syntax::tokenstream::TokenStream;
-use syntax::util::parser::ExprPrecedence;
 
 use smallvec::SmallVec;
 use std::collections::{BTreeMap, BTreeSet};
diff --git a/src/librustc_hir/intravisit.rs b/src/librustc_hir/intravisit.rs
index f574449c6b9..45257b04d79 100644
--- a/src/librustc_hir/intravisit.rs
+++ b/src/librustc_hir/intravisit.rs
@@ -34,9 +34,9 @@
 use crate::hir::*;
 use crate::hir_id::CRATE_HIR_ID;
 use crate::itemlikevisit::{ItemLikeVisitor, ParItemLikeVisitor};
+use rustc_ast::ast::{Attribute, Ident, Label, Name};
+use rustc_ast::walk_list;
 use rustc_span::Span;
-use syntax::ast::{Attribute, Ident, Label, Name};
-use syntax::walk_list;
 
 pub struct DeepVisitor<'v, V> {
     visitor: &'v mut V,
diff --git a/src/librustc_hir/lang_items.rs b/src/librustc_hir/lang_items.rs
index cb5ebba4633..fc91b68e3ea 100644
--- a/src/librustc_hir/lang_items.rs
+++ b/src/librustc_hir/lang_items.rs
@@ -12,12 +12,12 @@ pub use self::LangItem::*;
 use crate::def_id::DefId;
 use crate::Target;
 
+use rustc_ast::ast;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_macros::HashStable_Generic;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
-use syntax::ast;
 
 use lazy_static::lazy_static;
 
diff --git a/src/librustc_hir/pat_util.rs b/src/librustc_hir/pat_util.rs
index 6bca45b4f83..0b9ffdf21fe 100644
--- a/src/librustc_hir/pat_util.rs
+++ b/src/librustc_hir/pat_util.rs
@@ -1,8 +1,8 @@
 use crate::def::{CtorOf, DefKind, Res};
 use crate::def_id::DefId;
 use crate::hir::{self, HirId, PatKind};
+use rustc_ast::ast;
 use rustc_span::Span;
-use syntax::ast;
 
 use std::iter::{Enumerate, ExactSizeIterator};
 
diff --git a/src/librustc_hir/print.rs b/src/librustc_hir/print.rs
index 3fde04c294e..8cbbef959ce 100644
--- a/src/librustc_hir/print.rs
+++ b/src/librustc_hir/print.rs
@@ -1,3 +1,5 @@
+use rustc_ast::ast;
+use rustc_ast::util::parser::{self, AssocOp, Fixity};
 use rustc_ast_pretty::pp::Breaks::{Consistent, Inconsistent};
 use rustc_ast_pretty::pp::{self, Breaks};
 use rustc_ast_pretty::pprust::{Comments, PrintState};
@@ -5,8 +7,6 @@ use rustc_span::source_map::{SourceMap, Spanned};
 use rustc_span::symbol::{kw, IdentPrinter};
 use rustc_span::{self, BytePos, FileName};
 use rustc_target::spec::abi::Abi;
-use syntax::ast;
-use syntax::util::parser::{self, AssocOp, Fixity};
 
 use crate::hir;
 use crate::hir::{GenericArg, GenericParam, GenericParamKind, Node};
diff --git a/src/librustc_hir/stable_hash_impls.rs b/src/librustc_hir/stable_hash_impls.rs
index e8407b53701..3938a0369b9 100644
--- a/src/librustc_hir/stable_hash_impls.rs
+++ b/src/librustc_hir/stable_hash_impls.rs
@@ -6,7 +6,9 @@ use crate::hir_id::HirId;
 /// Requirements for a `StableHashingContext` to be used in this crate.
 /// This is a hack to allow using the `HashStable_Generic` derive macro
 /// instead of implementing everything in librustc.
-pub trait HashStableContext: syntax::HashStableContext + rustc_target::HashStableContext {
+pub trait HashStableContext:
+    rustc_ast::HashStableContext + rustc_target::HashStableContext
+{
     fn hash_hir_id(&mut self, _: HirId, hasher: &mut StableHasher);
     fn hash_body_id(&mut self, _: BodyId, hasher: &mut StableHasher);
     fn hash_reference_to_item(&mut self, _: HirId, hasher: &mut StableHasher);
diff --git a/src/librustc_hir/weak_lang_items.rs b/src/librustc_hir/weak_lang_items.rs
index 79182caae8c..405a31d5a69 100644
--- a/src/librustc_hir/weak_lang_items.rs
+++ b/src/librustc_hir/weak_lang_items.rs
@@ -3,9 +3,9 @@
 use crate::def_id::DefId;
 use crate::{lang_items, LangItem, LanguageItems};
 
+use rustc_ast::ast;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_span::symbol::{sym, Symbol};
-use syntax::ast;
 
 use lazy_static::lazy_static;
 
diff --git a/src/librustc_incremental/Cargo.toml b/src/librustc_incremental/Cargo.toml
index 71b2f0ee868..eddfb81ea8b 100644
--- a/src/librustc_incremental/Cargo.toml
+++ b/src/librustc_incremental/Cargo.toml
@@ -17,7 +17,7 @@ rustc = { path = "../librustc" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 rustc_hir = { path = "../librustc_hir" }
 rustc_serialize = { path = "../libserialize", package = "serialize" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
 rustc_fs_util = { path = "../librustc_fs_util" }
 rustc_session = { path = "../librustc_session" }
diff --git a/src/librustc_incremental/assert_dep_graph.rs b/src/librustc_incremental/assert_dep_graph.rs
index 51cc091b6c0..c82ed0c2c49 100644
--- a/src/librustc_incremental/assert_dep_graph.rs
+++ b/src/librustc_incremental/assert_dep_graph.rs
@@ -38,6 +38,7 @@ use rustc::dep_graph::debug::{DepNodeFilter, EdgeFilter};
 use rustc::dep_graph::{DepGraphQuery, DepKind, DepNode};
 use rustc::hir::map::Map;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::graph::implementation::{Direction, NodeIndex, INCOMING, OUTGOING};
 use rustc_hir as hir;
@@ -45,7 +46,6 @@ use rustc_hir::def_id::DefId;
 use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::ast;
 
 use std::env;
 use std::fs::{self, File};
diff --git a/src/librustc_incremental/assert_module_sources.rs b/src/librustc_incremental/assert_module_sources.rs
index 4dd08b517e1..261540abcad 100644
--- a/src/librustc_incremental/assert_module_sources.rs
+++ b/src/librustc_incremental/assert_module_sources.rs
@@ -23,11 +23,11 @@
 
 use rustc::mir::mono::CodegenUnitNameBuilder;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast;
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_session::cgu_reuse_tracker::*;
 use rustc_span::symbol::{sym, Symbol};
 use std::collections::BTreeSet;
-use syntax::ast;
 
 pub fn assert_module_sources(tcx: TyCtxt<'_>) {
     tcx.dep_graph.with_ignore(|| {
diff --git a/src/librustc_incremental/persist/dirty_clean.rs b/src/librustc_incremental/persist/dirty_clean.rs
index f6e2956e5b2..f304292d922 100644
--- a/src/librustc_incremental/persist/dirty_clean.rs
+++ b/src/librustc_incremental/persist/dirty_clean.rs
@@ -16,6 +16,7 @@
 use rustc::dep_graph::{label_strs, DepNode};
 use rustc::hir::map::Map;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast::{self, Attribute, NestedMetaItem};
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir as hir;
@@ -28,7 +29,6 @@ use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
 use std::iter::FromIterator;
 use std::vec::Vec;
-use syntax::ast::{self, Attribute, NestedMetaItem};
 
 const EXCEPT: Symbol = sym::except;
 const LABEL: Symbol = sym::label;
@@ -168,7 +168,7 @@ pub fn check_dirty_clean_annotations(tcx: TyCtxt<'_>) {
 
         // Note that we cannot use the existing "unused attribute"-infrastructure
         // here, since that is running before codegen. This is also the reason why
-        // all codegen-specific attributes are `Whitelisted` in syntax::feature_gate.
+        // all codegen-specific attributes are `Whitelisted` in rustc_ast::feature_gate.
         all_attrs.report_unchecked_attrs(&dirty_clean_visitor.checked_attrs);
     })
 }
diff --git a/src/librustc_infer/Cargo.toml b/src/librustc_infer/Cargo.toml
index a234a0024e8..de99214901d 100644
--- a/src/librustc_infer/Cargo.toml
+++ b/src/librustc_infer/Cargo.toml
@@ -25,4 +25,4 @@ rustc_session = { path = "../librustc_session" }
 rustc_span = { path = "../librustc_span" }
 rustc_target = { path = "../librustc_target" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
diff --git a/src/librustc_infer/infer/combine.rs b/src/librustc_infer/infer/combine.rs
index a10af56a0f0..9d06e26d9bb 100644
--- a/src/librustc_infer/infer/combine.rs
+++ b/src/librustc_infer/infer/combine.rs
@@ -39,9 +39,9 @@ use rustc::ty::relate::{self, Relate, RelateResult, TypeRelation};
 use rustc::ty::subst::SubstsRef;
 use rustc::ty::{self, InferConst, Ty, TyCtxt};
 use rustc::ty::{IntType, UintType};
+use rustc_ast::ast;
 use rustc_hir::def_id::DefId;
 use rustc_span::{Span, DUMMY_SP};
-use syntax::ast;
 
 #[derive(Clone)]
 pub struct CombineFields<'infcx, 'tcx> {
diff --git a/src/librustc_infer/infer/mod.rs b/src/librustc_infer/infer/mod.rs
index 26998f0a33c..11b08d468b1 100644
--- a/src/librustc_infer/infer/mod.rs
+++ b/src/librustc_infer/infer/mod.rs
@@ -25,6 +25,7 @@ use rustc::ty::subst::{GenericArg, InternalSubsts, SubstsRef};
 use rustc::ty::{self, GenericParamDefKind, InferConst, Ty, TyCtxt};
 use rustc::ty::{ConstVid, FloatVid, IntVid, TyVid};
 
+use rustc_ast::ast;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::unify as ut;
@@ -36,7 +37,6 @@ use rustc_span::Span;
 use std::cell::{Cell, Ref, RefCell};
 use std::collections::BTreeMap;
 use std::fmt;
-use syntax::ast;
 
 use self::combine::CombineFields;
 use self::lexical_region_resolve::LexicalRegionResolutions;
diff --git a/src/librustc_infer/traits/error_reporting/mod.rs b/src/librustc_infer/traits/error_reporting/mod.rs
index a2fe0236aec..471f388f0bb 100644
--- a/src/librustc_infer/traits/error_reporting/mod.rs
+++ b/src/librustc_infer/traits/error_reporting/mod.rs
@@ -21,6 +21,7 @@ use rustc::ty::SubtypePredicate;
 use rustc::ty::{
     self, AdtKind, ToPolyTraitRef, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness,
 };
+use rustc_ast::ast;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::{struct_span_err, Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
@@ -29,7 +30,6 @@ use rustc_hir::{QPath, TyKind, WhereBoundPredicate, WherePredicate};
 use rustc_span::source_map::SourceMap;
 use rustc_span::{ExpnKind, Span, DUMMY_SP};
 use std::fmt;
-use syntax::ast;
 
 impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
     pub fn report_fulfillment_errors(
diff --git a/src/librustc_infer/traits/on_unimplemented.rs b/src/librustc_infer/traits/on_unimplemented.rs
index 41201c1c7ae..04d7772de83 100644
--- a/src/librustc_infer/traits/on_unimplemented.rs
+++ b/src/librustc_infer/traits/on_unimplemented.rs
@@ -3,13 +3,13 @@ use fmt_macros::{Parser, Piece, Position};
 use rustc::ty::{self, GenericParamDefKind, TyCtxt};
 use rustc::util::common::ErrorReported;
 
+use rustc_ast::ast::{MetaItem, NestedMetaItem};
 use rustc_attr as attr;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::struct_span_err;
 use rustc_hir::def_id::DefId;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
-use syntax::ast::{MetaItem, NestedMetaItem};
 
 #[derive(Clone, Debug)]
 pub struct OnUnimplementedFormatString(Symbol);
diff --git a/src/librustc_infer/traits/project.rs b/src/librustc_infer/traits/project.rs
index 8d9e5d3fa20..cbe24320502 100644
--- a/src/librustc_infer/traits/project.rs
+++ b/src/librustc_infer/traits/project.rs
@@ -17,11 +17,11 @@ use crate::infer::{InferCtxt, InferOk, LateBoundRegionConversionTime};
 use rustc::ty::fold::{TypeFoldable, TypeFolder};
 use rustc::ty::subst::{InternalSubsts, Subst};
 use rustc::ty::{self, ToPolyTraitRef, ToPredicate, Ty, TyCtxt, WithConstness};
+use rustc_ast::ast::Ident;
 use rustc_data_structures::snapshot_map::{Snapshot, SnapshotMap};
 use rustc_hir::def_id::DefId;
 use rustc_span::symbol::sym;
 use rustc_span::DUMMY_SP;
-use syntax::ast::Ident;
 
 pub use rustc::traits::Reveal;
 
diff --git a/src/librustc_infer/traits/select.rs b/src/librustc_infer/traits/select.rs
index 925665763cb..d468e28ba4d 100644
--- a/src/librustc_infer/traits/select.rs
+++ b/src/librustc_infer/traits/select.rs
@@ -40,13 +40,13 @@ use rustc::ty::fast_reject;
 use rustc::ty::relate::TypeRelation;
 use rustc::ty::subst::{Subst, SubstsRef};
 use rustc::ty::{self, ToPolyTraitRef, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness};
+use rustc_ast::attr;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_index::bit_set::GrowableBitSet;
 use rustc_span::symbol::sym;
 use rustc_target::spec::abi::Abi;
-use syntax::attr;
 
 use std::cell::{Cell, RefCell};
 use std::cmp;
diff --git a/src/librustc_interface/Cargo.toml b/src/librustc_interface/Cargo.toml
index cc5d9da52cb..b29480a8810 100644
--- a/src/librustc_interface/Cargo.toml
+++ b/src/librustc_interface/Cargo.toml
@@ -13,7 +13,7 @@ doctest = false
 log = "0.4"
 rayon = { version = "0.3.0", package = "rustc-rayon" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_attr = { path = "../librustc_attr" }
 rustc_builtin_macros = { path = "../librustc_builtin_macros" }
 rustc_expand = { path = "../librustc_expand" }
diff --git a/src/librustc_interface/interface.rs b/src/librustc_interface/interface.rs
index e213a4d33a6..e15217dfa67 100644
--- a/src/librustc_interface/interface.rs
+++ b/src/librustc_interface/interface.rs
@@ -7,6 +7,8 @@ use rustc::session::early_error;
 use rustc::session::{DiagnosticOutput, Session};
 use rustc::ty;
 use rustc::util::common::ErrorReported;
+use rustc_ast::ast::{self, MetaItemKind};
+use rustc_ast::token;
 use rustc_codegen_utils::codegen_backend::CodegenBackend;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::sync::Lrc;
@@ -20,8 +22,6 @@ use rustc_span::source_map::{FileLoader, FileName, SourceMap};
 use std::path::PathBuf;
 use std::result;
 use std::sync::{Arc, Mutex};
-use syntax::ast::{self, MetaItemKind};
-use syntax::token;
 
 pub type Result<T> = result::Result<T, ErrorReported>;
 
@@ -78,7 +78,7 @@ impl Compiler {
 
 /// Converts strings provided as `--cfg [cfgspec]` into a `crate_cfg`.
 pub fn parse_cfgspecs(cfgspecs: Vec<String>) -> FxHashSet<(String, Option<String>)> {
-    syntax::with_default_globals(move || {
+    rustc_ast::with_default_globals(move || {
         let cfg = cfgspecs
             .into_iter()
             .map(|s| {
diff --git a/src/librustc_interface/passes.rs b/src/librustc_interface/passes.rs
index 96a2ac08f2c..1e9b76c3e14 100644
--- a/src/librustc_interface/passes.rs
+++ b/src/librustc_interface/passes.rs
@@ -16,6 +16,8 @@ use rustc::session::Session;
 use rustc::ty::steal::Steal;
 use rustc::ty::{self, GlobalCtxt, ResolverOutputs, TyCtxt};
 use rustc::util::common::ErrorReported;
+use rustc_ast::mut_visit::MutVisitor;
+use rustc_ast::{self, ast, visit};
 use rustc_codegen_ssa::back::link::emit_metadata;
 use rustc_codegen_utils::codegen_backend::CodegenBackend;
 use rustc_codegen_utils::link::filename_for_metadata;
@@ -36,8 +38,6 @@ use rustc_resolve::{Resolver, ResolverArenas};
 use rustc_span::symbol::Symbol;
 use rustc_span::FileName;
 use rustc_typeck as typeck;
-use syntax::mut_visit::MutVisitor;
-use syntax::{self, ast, visit};
 
 use rustc_serialize::json;
 use tempfile::Builder as TempFileBuilder;
diff --git a/src/librustc_interface/proc_macro_decls.rs b/src/librustc_interface/proc_macro_decls.rs
index 9238f88b2b5..076a8cef92c 100644
--- a/src/librustc_interface/proc_macro_decls.rs
+++ b/src/librustc_interface/proc_macro_decls.rs
@@ -1,10 +1,10 @@
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
+use rustc_ast::attr;
 use rustc_hir as hir;
 use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
 use rustc_hir::itemlikevisit::ItemLikeVisitor;
 use rustc_span::symbol::sym;
-use syntax::attr;
 
 pub fn find(tcx: TyCtxt<'_>) -> Option<DefId> {
     tcx.proc_macro_decls_static(LOCAL_CRATE)
diff --git a/src/librustc_interface/queries.rs b/src/librustc_interface/queries.rs
index 0c77ab57500..426d97cc09b 100644
--- a/src/librustc_interface/queries.rs
+++ b/src/librustc_interface/queries.rs
@@ -8,6 +8,7 @@ use rustc::session::Session;
 use rustc::ty::steal::Steal;
 use rustc::ty::{GlobalCtxt, ResolverOutputs};
 use rustc::util::common::ErrorReported;
+use rustc_ast::{self, ast};
 use rustc_codegen_utils::codegen_backend::CodegenBackend;
 use rustc_data_structures::sync::{Lrc, Once, WorkerLocal};
 use rustc_hir::def_id::LOCAL_CRATE;
@@ -18,7 +19,6 @@ use std::any::Any;
 use std::cell::{Ref, RefCell, RefMut};
 use std::mem;
 use std::rc::Rc;
-use syntax::{self, ast};
 
 /// Represent the result of a query.
 /// This result can be stolen with the `take` method and generated with the `compute` method.
diff --git a/src/librustc_interface/tests.rs b/src/librustc_interface/tests.rs
index ec75a1c6a39..1b80cf4e3db 100644
--- a/src/librustc_interface/tests.rs
+++ b/src/librustc_interface/tests.rs
@@ -18,7 +18,6 @@ use rustc_target::spec::{MergeFunctions, PanicStrategy, RelroLevel};
 use std::collections::{BTreeMap, BTreeSet};
 use std::iter::FromIterator;
 use std::path::PathBuf;
-use syntax;
 
 type CfgSpecs = FxHashSet<(String, Option<String>)>;
 
@@ -64,7 +63,7 @@ fn mk_map<K: Ord, V>(entries: Vec<(K, V)>) -> BTreeMap<K, V> {
 // When the user supplies --test we should implicitly supply --cfg test
 #[test]
 fn test_switch_implies_cfg_test() {
-    syntax::with_default_globals(|| {
+    rustc_ast::with_default_globals(|| {
         let matches = optgroups().parse(&["--test".to_string()]).unwrap();
         let (sess, cfg) = mk_session(matches);
         let cfg = build_configuration(&sess, to_crate_config(cfg));
@@ -75,7 +74,7 @@ fn test_switch_implies_cfg_test() {
 // When the user supplies --test and --cfg test, don't implicitly add another --cfg test
 #[test]
 fn test_switch_implies_cfg_test_unless_cfg_test() {
-    syntax::with_default_globals(|| {
+    rustc_ast::with_default_globals(|| {
         let matches = optgroups().parse(&["--test".to_string(), "--cfg=test".to_string()]).unwrap();
         let (sess, cfg) = mk_session(matches);
         let cfg = build_configuration(&sess, to_crate_config(cfg));
@@ -87,20 +86,20 @@ fn test_switch_implies_cfg_test_unless_cfg_test() {
 
 #[test]
 fn test_can_print_warnings() {
-    syntax::with_default_globals(|| {
+    rustc_ast::with_default_globals(|| {
         let matches = optgroups().parse(&["-Awarnings".to_string()]).unwrap();
         let (sess, _) = mk_session(matches);
         assert!(!sess.diagnostic().can_emit_warnings());
     });
 
-    syntax::with_default_globals(|| {
+    rustc_ast::with_default_globals(|| {
         let matches =
             optgroups().parse(&["-Awarnings".to_string(), "-Dwarnings".to_string()]).unwrap();
         let (sess, _) = mk_session(matches);
         assert!(sess.diagnostic().can_emit_warnings());
     });
 
-    syntax::with_default_globals(|| {
+    rustc_ast::with_default_globals(|| {
         let matches = optgroups().parse(&["-Adead_code".to_string()]).unwrap();
         let (sess, _) = mk_session(matches);
         assert!(sess.diagnostic().can_emit_warnings());
diff --git a/src/librustc_interface/util.rs b/src/librustc_interface/util.rs
index c52a3aefaba..10a8c0a63f1 100644
--- a/src/librustc_interface/util.rs
+++ b/src/librustc_interface/util.rs
@@ -1,6 +1,11 @@
 use log::info;
 use rustc::lint;
 use rustc::ty;
+use rustc_ast::ast::{AttrVec, BlockCheckMode};
+use rustc_ast::mut_visit::{visit_clobber, MutVisitor, *};
+use rustc_ast::ptr::P;
+use rustc_ast::util::lev_distance::find_best_match_for_name;
+use rustc_ast::{self, ast};
 use rustc_codegen_utils::codegen_backend::CodegenBackend;
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
@@ -29,11 +34,6 @@ use std::path::{Path, PathBuf};
 use std::sync::{Arc, Mutex, Once};
 #[cfg(not(parallel_compiler))]
 use std::{panic, thread};
-use syntax::ast::{AttrVec, BlockCheckMode};
-use syntax::mut_visit::{visit_clobber, MutVisitor, *};
-use syntax::ptr::P;
-use syntax::util::lev_distance::find_best_match_for_name;
-use syntax::{self, ast};
 
 /// Adds `target_feature = "..."` cfgs for a variety of platform
 /// specific features (SSE, NEON etc.).
@@ -147,7 +147,7 @@ pub fn spawn_thread_pool<F: FnOnce() -> R + Send, R: Send>(
     crate::callbacks::setup_callbacks();
 
     scoped_thread(cfg, || {
-        syntax::with_globals(edition, || {
+        rustc_ast::with_globals(edition, || {
             ty::tls::GCX_PTR.set(&Lock::new(0), || {
                 if let Some(stderr) = stderr {
                     io::set_panic(Some(box Sink(stderr.clone())));
@@ -183,15 +183,15 @@ pub fn spawn_thread_pool<F: FnOnce() -> R + Send, R: Send>(
 
     let with_pool = move |pool: &ThreadPool| pool.install(move || f());
 
-    syntax::with_globals(edition, || {
-        syntax::GLOBALS.with(|syntax_globals| {
+    rustc_ast::with_globals(edition, || {
+        rustc_ast::GLOBALS.with(|syntax_globals| {
             rustc_span::GLOBALS.with(|rustc_span_globals| {
                 // The main handler runs for each Rayon worker thread and sets up
                 // the thread local rustc uses. syntax_globals and rustc_span_globals are
                 // captured and set on the new threads. ty::tls::with_thread_locals sets up
                 // thread local callbacks from librustc_ast
                 let main_handler = move |thread: ThreadBuilder| {
-                    syntax::GLOBALS.set(syntax_globals, || {
+                    rustc_ast::GLOBALS.set(syntax_globals, || {
                         rustc_span::GLOBALS.set(rustc_span_globals, || {
                             if let Some(stderr) = stderr {
                                 io::set_panic(Some(box Sink(stderr.clone())));
diff --git a/src/librustc_lint/Cargo.toml b/src/librustc_lint/Cargo.toml
index d3b46557b69..6470d25fe0a 100644
--- a/src/librustc_lint/Cargo.toml
+++ b/src/librustc_lint/Cargo.toml
@@ -17,7 +17,7 @@ rustc_attr = { path = "../librustc_attr" }
 rustc_errors = { path = "../librustc_errors" }
 rustc_hir = { path = "../librustc_hir" }
 rustc_target = { path = "../librustc_target" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 rustc_feature = { path = "../librustc_feature" }
diff --git a/src/librustc_lint/builtin.rs b/src/librustc_lint/builtin.rs
index 4d03f4579fd..96526b3dad3 100644
--- a/src/librustc_lint/builtin.rs
+++ b/src/librustc_lint/builtin.rs
@@ -25,6 +25,10 @@ use crate::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext}
 use rustc::hir::map::Map;
 use rustc::lint::LintDiagnosticBuilder;
 use rustc::ty::{self, layout::VariantIdx, Ty, TyCtxt};
+use rustc_ast::ast::{self, Expr};
+use rustc_ast::attr::{self, HasAttrs};
+use rustc_ast::tokenstream::{TokenStream, TokenTree};
+use rustc_ast::visit::{FnCtxt, FnKind};
 use rustc_ast_pretty::pprust::{self, expr_to_string};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::{Applicability, DiagnosticBuilder};
@@ -41,10 +45,6 @@ use rustc_span::edition::Edition;
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::{BytePos, Span};
-use syntax::ast::{self, Expr};
-use syntax::attr::{self, HasAttrs};
-use syntax::tokenstream::{TokenStream, TokenTree};
-use syntax::visit::{FnCtxt, FnKind};
 
 use crate::nonstandard_style::{method_context, MethodLateContext};
 
@@ -1847,7 +1847,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for InvalidValue {
         /// Test if this constant is all-0.
         fn is_zero(expr: &hir::Expr<'_>) -> bool {
             use hir::ExprKind::*;
-            use syntax::ast::LitKind::*;
+            use rustc_ast::ast::LitKind::*;
             match &expr.kind {
                 Lit(lit) => {
                     if let Int(i, _) = lit.node {
diff --git a/src/librustc_lint/context.rs b/src/librustc_lint/context.rs
index adad1198b09..29a6b8c693f 100644
--- a/src/librustc_lint/context.rs
+++ b/src/librustc_lint/context.rs
@@ -25,6 +25,8 @@ use rustc::middle::privacy::AccessLevels;
 use rustc::middle::stability;
 use rustc::ty::layout::{LayoutError, LayoutOf, TyLayout};
 use rustc::ty::{self, print::Printer, subst::GenericArg, Ty, TyCtxt};
+use rustc_ast::ast;
+use rustc_ast::util::lev_distance::find_best_match_for_name;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync;
 use rustc_errors::{struct_span_err, Applicability};
@@ -34,8 +36,6 @@ use rustc_session::lint::BuiltinLintDiagnostics;
 use rustc_session::lint::{FutureIncompatibleInfo, Level, Lint, LintBuffer, LintId};
 use rustc_session::Session;
 use rustc_span::{symbol::Symbol, MultiSpan, Span, DUMMY_SP};
-use syntax::ast;
-use syntax::util::lev_distance::find_best_match_for_name;
 
 use std::slice;
 
diff --git a/src/librustc_lint/early.rs b/src/librustc_lint/early.rs
index 4d8ead34ea9..ff6e9e000b0 100644
--- a/src/librustc_lint/early.rs
+++ b/src/librustc_lint/early.rs
@@ -16,11 +16,11 @@
 
 use crate::context::{EarlyContext, LintContext, LintStore};
 use crate::passes::{EarlyLintPass, EarlyLintPassObject};
+use rustc_ast::ast;
+use rustc_ast::visit as ast_visit;
 use rustc_session::lint::{LintBuffer, LintPass};
 use rustc_session::Session;
 use rustc_span::Span;
-use syntax::ast;
-use syntax::visit as ast_visit;
 
 use log::debug;
 use std::slice;
diff --git a/src/librustc_lint/internal.rs b/src/librustc_lint/internal.rs
index 78752619112..db109aef6eb 100644
--- a/src/librustc_lint/internal.rs
+++ b/src/librustc_lint/internal.rs
@@ -2,13 +2,13 @@
 //! Clippy.
 
 use crate::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext};
+use rustc_ast::ast::{Ident, Item, ItemKind};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::Applicability;
 use rustc_hir::{GenericArg, HirId, MutTy, Mutability, Path, PathSegment, QPath, Ty, TyKind};
 use rustc_session::{declare_lint_pass, declare_tool_lint, impl_lint_pass};
 use rustc_span::hygiene::{ExpnKind, MacroKind};
 use rustc_span::symbol::{sym, Symbol};
-use syntax::ast::{Ident, Item, ItemKind};
 
 declare_tool_lint! {
     pub rustc::DEFAULT_HASH_TYPES,
diff --git a/src/librustc_lint/late.rs b/src/librustc_lint/late.rs
index b3d5cdf15c9..ee03232a0ce 100644
--- a/src/librustc_lint/late.rs
+++ b/src/librustc_lint/late.rs
@@ -17,6 +17,8 @@
 use crate::{passes::LateLintPassObject, LateContext, LateLintPass, LintStore};
 use rustc::hir::map::Map;
 use rustc::ty::{self, TyCtxt};
+use rustc_ast::ast;
+use rustc_ast::walk_list;
 use rustc_data_structures::sync::{join, par_iter, ParallelIterator};
 use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
@@ -24,8 +26,6 @@ use rustc_hir::intravisit as hir_visit;
 use rustc_hir::intravisit::Visitor;
 use rustc_session::lint::LintPass;
 use rustc_span::Span;
-use syntax::ast;
-use syntax::walk_list;
 
 use log::debug;
 use std::any::Any;
diff --git a/src/librustc_lint/levels.rs b/src/librustc_lint/levels.rs
index 8e1947e52ca..7da69f3ed26 100644
--- a/src/librustc_lint/levels.rs
+++ b/src/librustc_lint/levels.rs
@@ -5,6 +5,9 @@ use rustc::lint::LintDiagnosticBuilder;
 use rustc::lint::{struct_lint_level, LintLevelMap, LintLevelSets, LintSet, LintSource};
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast;
+use rustc_ast::attr;
+use rustc_ast::unwrap_or;
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::{struct_span_err, Applicability};
@@ -16,9 +19,6 @@ use rustc_session::parse::feature_err;
 use rustc_session::Session;
 use rustc_span::source_map::MultiSpan;
 use rustc_span::symbol::{sym, Symbol};
-use syntax::ast;
-use syntax::attr;
-use syntax::unwrap_or;
 
 use std::cmp;
 
diff --git a/src/librustc_lint/lib.rs b/src/librustc_lint/lib.rs
index 7b42cd0e4a2..895c42a84d8 100644
--- a/src/librustc_lint/lib.rs
+++ b/src/librustc_lint/lib.rs
@@ -55,6 +55,7 @@ mod unused;
 
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_session::lint::builtin::{
@@ -62,7 +63,6 @@ use rustc_session::lint::builtin::{
     INTRA_DOC_LINK_RESOLUTION_FAILURE, MISSING_DOC_CODE_EXAMPLES, PRIVATE_DOC_TESTS,
 };
 use rustc_span::Span;
-use syntax::ast;
 
 use array_into_iter::ArrayIntoIter;
 use builtin::*;
diff --git a/src/librustc_lint/non_ascii_idents.rs b/src/librustc_lint/non_ascii_idents.rs
index a0ca7ad1860..470fac2675b 100644
--- a/src/librustc_lint/non_ascii_idents.rs
+++ b/src/librustc_lint/non_ascii_idents.rs
@@ -1,5 +1,5 @@
 use crate::{EarlyContext, EarlyLintPass, LintContext};
-use syntax::ast;
+use rustc_ast::ast;
 
 declare_lint! {
     pub NON_ASCII_IDENTS,
diff --git a/src/librustc_lint/nonstandard_style.rs b/src/librustc_lint/nonstandard_style.rs
index 8c58f2ba4c0..b0560dc9fdf 100644
--- a/src/librustc_lint/nonstandard_style.rs
+++ b/src/librustc_lint/nonstandard_style.rs
@@ -1,5 +1,6 @@
 use crate::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext};
 use rustc::ty;
+use rustc_ast::ast;
 use rustc_attr as attr;
 use rustc_errors::Applicability;
 use rustc_hir as hir;
@@ -9,7 +10,6 @@ use rustc_hir::{GenericParamKind, PatKind};
 use rustc_span::symbol::sym;
 use rustc_span::{symbol::Ident, BytePos, Span};
 use rustc_target::spec::abi::Abi;
-use syntax::ast;
 
 #[derive(PartialEq)]
 pub enum MethodLateContext {
diff --git a/src/librustc_lint/passes.rs b/src/librustc_lint/passes.rs
index 36de625cafa..813be2a032f 100644
--- a/src/librustc_lint/passes.rs
+++ b/src/librustc_lint/passes.rs
@@ -1,11 +1,11 @@
 use crate::context::{EarlyContext, LateContext};
 
+use rustc_ast::ast;
 use rustc_data_structures::sync;
 use rustc_hir as hir;
 use rustc_session::lint::builtin::HardwiredLints;
 use rustc_session::lint::LintPass;
 use rustc_span::Span;
-use syntax::ast;
 
 #[macro_export]
 macro_rules! late_lint_methods {
@@ -179,9 +179,9 @@ macro_rules! early_lint_methods {
             fn check_where_predicate(a: &ast::WherePredicate);
             fn check_poly_trait_ref(a: &ast::PolyTraitRef,
                                     b: &ast::TraitBoundModifier);
-            fn check_fn(a: syntax::visit::FnKind<'_>, c: Span, d_: ast::NodeId);
+            fn check_fn(a: rustc_ast::visit::FnKind<'_>, c: Span, d_: ast::NodeId);
             fn check_fn_post(
-                a: syntax::visit::FnKind<'_>,
+                a: rustc_ast::visit::FnKind<'_>,
                 c: Span,
                 d: ast::NodeId
             );
diff --git a/src/librustc_lint/redundant_semicolon.rs b/src/librustc_lint/redundant_semicolon.rs
index 68cb0b54f56..0b66fd92430 100644
--- a/src/librustc_lint/redundant_semicolon.rs
+++ b/src/librustc_lint/redundant_semicolon.rs
@@ -1,6 +1,6 @@
 use crate::{EarlyContext, EarlyLintPass, LintContext};
+use rustc_ast::ast::{ExprKind, Stmt, StmtKind};
 use rustc_errors::Applicability;
-use syntax::ast::{ExprKind, Stmt, StmtKind};
 
 declare_lint! {
     pub REDUNDANT_SEMICOLON,
diff --git a/src/librustc_lint/types.rs b/src/librustc_lint/types.rs
index 6901a66b1ce..86d93612e99 100644
--- a/src/librustc_lint/types.rs
+++ b/src/librustc_lint/types.rs
@@ -5,6 +5,7 @@ use rustc::mir::interpret::{sign_extend, truncate};
 use rustc::ty::layout::{self, IntegerExt, LayoutOf, SizeSkeleton, VariantIdx};
 use rustc::ty::subst::SubstsRef;
 use rustc::ty::{self, AdtKind, ParamEnv, Ty, TyCtxt};
+use rustc_ast::ast;
 use rustc_attr as attr;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::Applicability;
@@ -16,7 +17,6 @@ use rustc_span::source_map;
 use rustc_span::symbol::sym;
 use rustc_span::Span;
 use rustc_target::spec::abi::Abi;
-use syntax::ast;
 
 use log::debug;
 use std::cmp;
@@ -194,8 +194,8 @@ fn report_bin_hex_error(
 //
 // No suggestion for: `isize`, `usize`.
 fn get_type_suggestion(t: Ty<'_>, val: u128, negative: bool) -> Option<&'static str> {
-    use syntax::ast::IntTy::*;
-    use syntax::ast::UintTy::*;
+    use rustc_ast::ast::IntTy::*;
+    use rustc_ast::ast::UintTy::*;
     macro_rules! find_fit {
         ($ty:expr, $val:expr, $negative:expr,
          $($type:ident => [$($utypes:expr),*] => [$($itypes:expr),*]),+) => {
diff --git a/src/librustc_lint/unused.rs b/src/librustc_lint/unused.rs
index 7870b9da4cb..7b6741954d9 100644
--- a/src/librustc_lint/unused.rs
+++ b/src/librustc_lint/unused.rs
@@ -1,6 +1,9 @@
 use crate::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext};
 use rustc::ty::adjustment;
 use rustc::ty::{self, Ty};
+use rustc_ast::ast;
+use rustc_ast::attr;
+use rustc_ast::util::parser;
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::{pluralize, Applicability};
@@ -12,9 +15,6 @@ use rustc_session::lint::builtin::UNUSED_ATTRIBUTES;
 use rustc_span::symbol::Symbol;
 use rustc_span::symbol::{kw, sym};
 use rustc_span::{BytePos, Span};
-use syntax::ast;
-use syntax::attr;
-use syntax::util::parser;
 
 use log::debug;
 
@@ -469,7 +469,7 @@ impl UnusedParens {
 
 impl EarlyLintPass for UnusedParens {
     fn check_expr(&mut self, cx: &EarlyContext<'_>, e: &ast::Expr) {
-        use syntax::ast::ExprKind::*;
+        use rustc_ast::ast::ExprKind::*;
         let (value, msg, followed_by_block, left_pos, right_pos) = match e.kind {
             Let(ref pat, ..) => {
                 self.check_unused_parens_pat(cx, pat, false, false);
diff --git a/src/librustc_metadata/Cargo.toml b/src/librustc_metadata/Cargo.toml
index b44822efc16..8abfb20965e 100644
--- a/src/librustc_metadata/Cargo.toml
+++ b/src/librustc_metadata/Cargo.toml
@@ -24,7 +24,7 @@ rustc_target = { path = "../librustc_target" }
 rustc_index = { path = "../librustc_index" }
 rustc_serialize = { path = "../libserialize", package = "serialize" }
 stable_deref_trait = "1.0.0"
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_expand = { path = "../librustc_expand" }
 rustc_parse = { path = "../librustc_parse" }
 rustc_span = { path = "../librustc_span" }
diff --git a/src/librustc_metadata/creader.rs b/src/librustc_metadata/creader.rs
index 647224bc8d6..293a353a092 100644
--- a/src/librustc_metadata/creader.rs
+++ b/src/librustc_metadata/creader.rs
@@ -10,6 +10,9 @@ use rustc::session::config;
 use rustc::session::search_paths::PathKind;
 use rustc::session::{CrateDisambiguator, Session};
 use rustc::ty::TyCtxt;
+use rustc_ast::ast;
+use rustc_ast::attr;
+use rustc_ast::expand::allocator::{global_allocator_spans, AllocatorKind};
 use rustc_data_structures::svh::Svh;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::struct_span_err;
@@ -20,9 +23,6 @@ use rustc_span::edition::Edition;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{Span, DUMMY_SP};
 use rustc_target::spec::{PanicStrategy, TargetTriple};
-use syntax::ast;
-use syntax::attr;
-use syntax::expand::allocator::{global_allocator_spans, AllocatorKind};
 
 use log::{debug, info, log_enabled};
 use proc_macro::bridge::client::ProcMacro;
diff --git a/src/librustc_metadata/rmeta/decoder.rs b/src/librustc_metadata/rmeta/decoder.rs
index 72e07c6c2b8..a72ee0cbe47 100644
--- a/src/librustc_metadata/rmeta/decoder.rs
+++ b/src/librustc_metadata/rmeta/decoder.rs
@@ -34,6 +34,7 @@ use std::u32;
 
 use log::debug;
 use proc_macro::bridge::client::ProcMacro;
+use rustc_ast::ast::{self, Ident};
 use rustc_attr as attr;
 use rustc_expand::base::{SyntaxExtension, SyntaxExtensionKind};
 use rustc_expand::proc_macro::{AttrProcMacro, BangProcMacro, ProcMacroDerive};
@@ -41,7 +42,6 @@ use rustc_serialize::{opaque, Decodable, Decoder, SpecializedDecoder};
 use rustc_span::source_map::{self, respan, Spanned};
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{self, hygiene::MacroKind, BytePos, Pos, Span, DUMMY_SP};
-use syntax::ast::{self, Ident};
 
 pub use cstore_impl::{provide, provide_extern};
 
diff --git a/src/librustc_metadata/rmeta/decoder/cstore_impl.rs b/src/librustc_metadata/rmeta/decoder/cstore_impl.rs
index e6270e90329..50ab3811f52 100644
--- a/src/librustc_metadata/rmeta/decoder/cstore_impl.rs
+++ b/src/librustc_metadata/rmeta/decoder/cstore_impl.rs
@@ -25,15 +25,15 @@ use smallvec::SmallVec;
 use std::any::Any;
 use std::sync::Arc;
 
+use rustc_ast::ast;
+use rustc_ast::attr;
+use rustc_ast::expand::allocator::AllocatorKind;
+use rustc_ast::ptr::P;
+use rustc_ast::tokenstream::DelimSpan;
 use rustc_span::source_map;
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::Symbol;
 use rustc_span::{FileName, Span};
-use syntax::ast;
-use syntax::attr;
-use syntax::expand::allocator::AllocatorKind;
-use syntax::ptr::P;
-use syntax::tokenstream::DelimSpan;
 
 macro_rules! provide {
     (<$lt:tt> $tcx:ident, $def_id:ident, $other:ident, $cdata:ident,
diff --git a/src/librustc_metadata/rmeta/encoder.rs b/src/librustc_metadata/rmeta/encoder.rs
index ee54f40ece5..418b97b74c8 100644
--- a/src/librustc_metadata/rmeta/encoder.rs
+++ b/src/librustc_metadata/rmeta/encoder.rs
@@ -25,6 +25,8 @@ use rustc_data_structures::sync::Lrc;
 use rustc_serialize::{opaque, Encodable, Encoder, SpecializedEncoder};
 
 use log::{debug, trace};
+use rustc_ast::ast;
+use rustc_ast::attr;
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{self, FileName, SourceFile, Span};
@@ -32,8 +34,6 @@ use std::hash::Hash;
 use std::num::NonZeroUsize;
 use std::path::Path;
 use std::u32;
-use syntax::ast;
-use syntax::attr;
 
 use rustc_hir as hir;
 use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
diff --git a/src/librustc_metadata/rmeta/mod.rs b/src/librustc_metadata/rmeta/mod.rs
index 01a3f6c560f..9b05fd4734c 100644
--- a/src/librustc_metadata/rmeta/mod.rs
+++ b/src/librustc_metadata/rmeta/mod.rs
@@ -10,6 +10,7 @@ use rustc::mir;
 use rustc::session::config::SymbolManglingVersion;
 use rustc::session::CrateDisambiguator;
 use rustc::ty::{self, ReprOptions, Ty};
+use rustc_ast::ast;
 use rustc_attr as attr;
 use rustc_data_structures::svh::Svh;
 use rustc_data_structures::sync::MetadataRef;
@@ -22,7 +23,6 @@ use rustc_span::edition::Edition;
 use rustc_span::symbol::Symbol;
 use rustc_span::{self, Span};
 use rustc_target::spec::{PanicStrategy, TargetTriple};
-use syntax::ast;
 
 use std::marker::PhantomData;
 use std::num::NonZeroUsize;
diff --git a/src/librustc_mir/Cargo.toml b/src/librustc_mir/Cargo.toml
index 9c94a5a5949..6e606230b63 100644
--- a/src/librustc_mir/Cargo.toml
+++ b/src/librustc_mir/Cargo.toml
@@ -28,7 +28,7 @@ rustc_lexer = { path = "../librustc_lexer" }
 rustc_macros = { path = "../librustc_macros" }
 rustc_serialize = { path = "../libserialize", package = "serialize" }
 rustc_target = { path = "../librustc_target" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
 rustc_apfloat = { path = "../librustc_apfloat" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
diff --git a/src/librustc_mir/borrow_check/mod.rs b/src/librustc_mir/borrow_check/mod.rs
index aa49ab1b722..28974dcd08b 100644
--- a/src/librustc_mir/borrow_check/mod.rs
+++ b/src/librustc_mir/borrow_check/mod.rs
@@ -28,8 +28,8 @@ use std::collections::BTreeMap;
 use std::mem;
 use std::rc::Rc;
 
+use rustc_ast::ast::Name;
 use rustc_span::{Span, DUMMY_SP};
-use syntax::ast::Name;
 
 use crate::dataflow;
 use crate::dataflow::generic::{Analysis, BorrowckFlowState as Flows, BorrowckResults};
diff --git a/src/librustc_mir/dataflow/generic/engine.rs b/src/librustc_mir/dataflow/generic/engine.rs
index 371bfa9a6fd..3373151f82c 100644
--- a/src/librustc_mir/dataflow/generic/engine.rs
+++ b/src/librustc_mir/dataflow/generic/engine.rs
@@ -6,12 +6,12 @@ use std::path::PathBuf;
 
 use rustc::mir::{self, traversal, BasicBlock, Location};
 use rustc::ty::{self, TyCtxt};
+use rustc_ast::ast;
 use rustc_data_structures::work_queue::WorkQueue;
 use rustc_hir::def_id::DefId;
 use rustc_index::bit_set::BitSet;
 use rustc_index::vec::IndexVec;
 use rustc_span::symbol::{sym, Symbol};
-use syntax::ast;
 
 use super::graphviz;
 use super::{Analysis, GenKillAnalysis, GenKillSet, Results};
diff --git a/src/librustc_mir/dataflow/mod.rs b/src/librustc_mir/dataflow/mod.rs
index a0d93d6d19a..4d86ed9cab2 100644
--- a/src/librustc_mir/dataflow/mod.rs
+++ b/src/librustc_mir/dataflow/mod.rs
@@ -1,6 +1,6 @@
+use rustc_ast::ast::{self, MetaItem};
 use rustc_ast_pretty::pprust;
 use rustc_span::symbol::{sym, Symbol};
-use syntax::ast::{self, MetaItem};
 
 use rustc_data_structures::work_queue::WorkQueue;
 use rustc_index::bit_set::{BitSet, HybridBitSet};
diff --git a/src/librustc_mir/interpret/cast.rs b/src/librustc_mir/interpret/cast.rs
index 9461a066902..1a0be582ce6 100644
--- a/src/librustc_mir/interpret/cast.rs
+++ b/src/librustc_mir/interpret/cast.rs
@@ -1,8 +1,8 @@
 use rustc::ty::adjustment::PointerCast;
 use rustc::ty::layout::{self, Size, TyLayout};
 use rustc::ty::{self, Ty, TypeAndMut, TypeFoldable};
+use rustc_ast::ast::FloatTy;
 use rustc_span::symbol::sym;
-use syntax::ast::FloatTy;
 
 use rustc::mir::interpret::{InterpResult, PointerArithmetic, Scalar};
 use rustc::mir::CastKind;
diff --git a/src/librustc_mir/interpret/intern.rs b/src/librustc_mir/interpret/intern.rs
index 9fea82d78c9..747b2dd4aa0 100644
--- a/src/librustc_mir/interpret/intern.rs
+++ b/src/librustc_mir/interpret/intern.rs
@@ -9,7 +9,7 @@ use rustc::ty::{self, Ty};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 
-use syntax::ast::Mutability;
+use rustc_ast::ast::Mutability;
 
 use super::{AllocId, Allocation, InterpCx, MPlaceTy, Machine, MemoryKind, Scalar, ValueVisitor};
 
diff --git a/src/librustc_mir/interpret/memory.rs b/src/librustc_mir/interpret/memory.rs
index 1df389d9c8b..032a4bd5850 100644
--- a/src/librustc_mir/interpret/memory.rs
+++ b/src/librustc_mir/interpret/memory.rs
@@ -14,7 +14,7 @@ use rustc::ty::layout::{Align, HasDataLayout, Size, TargetDataLayout};
 use rustc::ty::{self, query::TyCtxtAt, Instance, ParamEnv};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 
-use syntax::ast::Mutability;
+use rustc_ast::ast::Mutability;
 
 use super::{
     AllocId, AllocMap, Allocation, AllocationExtra, CheckInAllocMsg, ErrorHandled, GlobalAlloc,
diff --git a/src/librustc_mir/interpret/operand.rs b/src/librustc_mir/interpret/operand.rs
index 14b8a341e26..ed2d2243ab4 100644
--- a/src/librustc_mir/interpret/operand.rs
+++ b/src/librustc_mir/interpret/operand.rs
@@ -13,8 +13,8 @@ pub use rustc::mir::interpret::ScalarMaybeUndef;
 use rustc::mir::interpret::{
     sign_extend, truncate, AllocId, ConstValue, GlobalId, InterpResult, Pointer, Scalar,
 };
+use rustc_ast::ast;
 use rustc_macros::HashStable;
-use syntax::ast;
 
 /// An `Immediate` represents a single immediate self-contained Rust value.
 ///
diff --git a/src/librustc_mir/interpret/operator.rs b/src/librustc_mir/interpret/operator.rs
index 2e8c94903ca..cd7a419af95 100644
--- a/src/librustc_mir/interpret/operator.rs
+++ b/src/librustc_mir/interpret/operator.rs
@@ -6,7 +6,7 @@ use rustc::ty::{
     Ty,
 };
 use rustc_apfloat::Float;
-use syntax::ast::FloatTy;
+use rustc_ast::ast::FloatTy;
 
 use super::{ImmTy, Immediate, InterpCx, Machine, PlaceTy};
 
diff --git a/src/librustc_mir/interpret/snapshot.rs b/src/librustc_mir/interpret/snapshot.rs
index a8e67c8f208..2353b74016c 100644
--- a/src/librustc_mir/interpret/snapshot.rs
+++ b/src/librustc_mir/interpret/snapshot.rs
@@ -15,12 +15,12 @@ use rustc::mir::interpret::{
 
 use rustc::ty::layout::{Align, Size};
 use rustc::ty::{self, TyCtxt};
+use rustc_ast::ast::Mutability;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_index::vec::IndexVec;
 use rustc_macros::HashStable;
 use rustc_span::source_map::Span;
-use syntax::ast::Mutability;
 
 use super::eval_context::{LocalState, StackPopCleanup};
 use super::{
diff --git a/src/librustc_mir/transform/const_prop.rs b/src/librustc_mir/transform/const_prop.rs
index 9e05133132e..654130c6fab 100644
--- a/src/librustc_mir/transform/const_prop.rs
+++ b/src/librustc_mir/transform/const_prop.rs
@@ -20,6 +20,7 @@ use rustc::ty::layout::{
 };
 use rustc::ty::subst::{InternalSubsts, Subst};
 use rustc::ty::{self, ConstKind, Instance, ParamEnv, Ty, TyCtxt, TypeFoldable};
+use rustc_ast::ast::Mutability;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::DefId;
@@ -27,7 +28,6 @@ use rustc_hir::HirId;
 use rustc_index::vec::IndexVec;
 use rustc_infer::traits;
 use rustc_span::Span;
-use syntax::ast::Mutability;
 
 use crate::const_eval::error_to_const_error;
 use crate::interpret::{
diff --git a/src/librustc_mir/transform/mod.rs b/src/librustc_mir/transform/mod.rs
index c534c2f3bb8..57e002bf3f3 100644
--- a/src/librustc_mir/transform/mod.rs
+++ b/src/librustc_mir/transform/mod.rs
@@ -4,13 +4,13 @@ use rustc::mir::{BodyAndCache, ConstQualifs, MirPhase, Promoted};
 use rustc::ty::query::Providers;
 use rustc::ty::steal::Steal;
 use rustc::ty::{InstanceDef, TyCtxt, TypeFoldable};
+use rustc_ast::ast;
 use rustc_hir as hir;
 use rustc_hir::def_id::{CrateNum, DefId, DefIdSet, LOCAL_CRATE};
 use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
 use rustc_index::vec::IndexVec;
 use rustc_span::Span;
 use std::borrow::Cow;
-use syntax::ast;
 
 pub mod add_call_guards;
 pub mod add_moves_for_packed_drops;
diff --git a/src/librustc_mir/transform/promote_consts.rs b/src/librustc_mir/transform/promote_consts.rs
index a5d59860c3d..286740f99dd 100644
--- a/src/librustc_mir/transform/promote_consts.rs
+++ b/src/librustc_mir/transform/promote_consts.rs
@@ -18,10 +18,10 @@ use rustc::mir::*;
 use rustc::ty::cast::CastTy;
 use rustc::ty::subst::InternalSubsts;
 use rustc::ty::{self, List, TyCtxt, TypeFoldable};
+use rustc_ast::ast::LitKind;
 use rustc_hir::def_id::DefId;
 use rustc_span::symbol::sym;
 use rustc_span::{Span, DUMMY_SP};
-use syntax::ast::LitKind;
 
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_target::spec::abi::Abi;
diff --git a/src/librustc_mir/transform/rustc_peek.rs b/src/librustc_mir/transform/rustc_peek.rs
index 6176cf8bc0f..2ae7bd4d727 100644
--- a/src/librustc_mir/transform/rustc_peek.rs
+++ b/src/librustc_mir/transform/rustc_peek.rs
@@ -1,7 +1,7 @@
+use rustc_ast::ast;
 use rustc_span::symbol::sym;
 use rustc_span::Span;
 use rustc_target::spec::abi::Abi;
-use syntax::ast;
 
 use crate::transform::{MirPass, MirSource};
 use rustc::mir::{self, Body, BodyAndCache, Local, Location};
diff --git a/src/librustc_mir_build/Cargo.toml b/src/librustc_mir_build/Cargo.toml
index f32633ab4fd..d53188a39e5 100644
--- a/src/librustc_mir_build/Cargo.toml
+++ b/src/librustc_mir_build/Cargo.toml
@@ -25,5 +25,5 @@ rustc_serialize = { path = "../libserialize", package = "serialize" }
 rustc_session = { path = "../librustc_session" }
 rustc_span = { path = "../librustc_span" }
 rustc_target = { path = "../librustc_target" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
diff --git a/src/librustc_mir_build/build/matches/mod.rs b/src/librustc_mir_build/build/matches/mod.rs
index bb61e56a2c5..e7c7e2b47f2 100644
--- a/src/librustc_mir_build/build/matches/mod.rs
+++ b/src/librustc_mir_build/build/matches/mod.rs
@@ -19,7 +19,7 @@ use rustc_hir::HirId;
 use rustc_index::bit_set::BitSet;
 use rustc_span::Span;
 use smallvec::{smallvec, SmallVec};
-use syntax::ast::Name;
+use rustc_ast::ast::Name;
 
 // helper functions, broken out by category:
 mod simplify;
diff --git a/src/librustc_mir_build/hair/constant.rs b/src/librustc_mir_build/hair/constant.rs
index e9dd7854275..d5e5398b9d4 100644
--- a/src/librustc_mir_build/hair/constant.rs
+++ b/src/librustc_mir_build/hair/constant.rs
@@ -2,8 +2,8 @@ use rustc::mir::interpret::{
     truncate, Allocation, ConstValue, LitToConstError, LitToConstInput, Scalar,
 };
 use rustc::ty::{self, layout::Size, ParamEnv, TyCtxt, TyS};
+use rustc_ast::ast;
 use rustc_span::symbol::Symbol;
-use syntax::ast;
 
 crate fn lit_to_const<'tcx>(
     tcx: TyCtxt<'tcx>,
diff --git a/src/librustc_mir_build/hair/cx/mod.rs b/src/librustc_mir_build/hair/cx/mod.rs
index f4860733db8..449e2e74946 100644
--- a/src/librustc_mir_build/hair/cx/mod.rs
+++ b/src/librustc_mir_build/hair/cx/mod.rs
@@ -11,14 +11,14 @@ use rustc::ty::layout::VariantIdx;
 use rustc::ty::subst::Subst;
 use rustc::ty::subst::{GenericArg, InternalSubsts};
 use rustc::ty::{self, Ty, TyCtxt};
+use rustc_ast::ast;
+use rustc_ast::attr;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_hir::Node;
 use rustc_index::vec::Idx;
 use rustc_infer::infer::InferCtxt;
 use rustc_span::symbol::{sym, Symbol};
-use syntax::ast;
-use syntax::attr;
 
 #[derive(Clone)]
 crate struct Cx<'a, 'tcx> {
diff --git a/src/librustc_mir_build/hair/pattern/check_match.rs b/src/librustc_mir_build/hair/pattern/check_match.rs
index 3dfe826ad2a..edd05ee0aa9 100644
--- a/src/librustc_mir_build/hair/pattern/check_match.rs
+++ b/src/librustc_mir_build/hair/pattern/check_match.rs
@@ -6,6 +6,7 @@ use super::{PatCtxt, PatKind, PatternError};
 
 use rustc::hir::map::Map;
 use rustc::ty::{self, Ty, TyCtxt};
+use rustc_ast::ast::Mutability;
 use rustc_errors::{error_code, struct_span_err, Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
 use rustc_hir::def::*;
@@ -17,7 +18,6 @@ use rustc_session::lint::builtin::{IRREFUTABLE_LET_PATTERNS, UNREACHABLE_PATTERN
 use rustc_session::parse::feature_err;
 use rustc_session::Session;
 use rustc_span::{sym, Span};
-use syntax::ast::Mutability;
 
 use std::slice;
 
diff --git a/src/librustc_mir_build/hair/pattern/mod.rs b/src/librustc_mir_build/hair/pattern/mod.rs
index 6979a98e687..f58216fbb4e 100644
--- a/src/librustc_mir_build/hair/pattern/mod.rs
+++ b/src/librustc_mir_build/hair/pattern/mod.rs
@@ -16,6 +16,7 @@ use rustc::ty::layout::VariantIdx;
 use rustc::ty::subst::{GenericArg, SubstsRef};
 use rustc::ty::{self, AdtDef, DefIdTree, Region, Ty, TyCtxt, UserType};
 use rustc::ty::{CanonicalUserType, CanonicalUserTypeAnnotation, CanonicalUserTypeAnnotations};
+use rustc_ast::ast;
 use rustc_errors::struct_span_err;
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res};
@@ -23,7 +24,6 @@ use rustc_hir::pat_util::EnumerateAndAdjustIterator;
 use rustc_hir::RangeEnd;
 use rustc_index::vec::Idx;
 use rustc_span::{Span, DUMMY_SP};
-use syntax::ast;
 
 use std::cmp::Ordering;
 use std::fmt;
diff --git a/src/librustc_parse/Cargo.toml b/src/librustc_parse/Cargo.toml
index d15066437a7..b02cabab0a8 100644
--- a/src/librustc_parse/Cargo.toml
+++ b/src/librustc_parse/Cargo.toml
@@ -21,5 +21,5 @@ rustc_errors = { path = "../librustc_errors" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
 rustc_session = { path = "../librustc_session" }
 rustc_span = { path = "../librustc_span" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 unicode-normalization = "0.1.11"
diff --git a/src/librustc_parse/config.rs b/src/librustc_parse/config.rs
index ec0d251a3f8..17b9e78e5df 100644
--- a/src/librustc_parse/config.rs
+++ b/src/librustc_parse/config.rs
@@ -9,6 +9,11 @@
 //! [#64197]: https://github.com/rust-lang/rust/issues/64197
 
 use crate::{parse_in, validate_attr};
+use rustc_ast::ast::{self, AttrItem, Attribute, MetaItem};
+use rustc_ast::attr::HasAttrs;
+use rustc_ast::mut_visit::*;
+use rustc_ast::ptr::P;
+use rustc_ast::util::map_in_place::MapInPlace;
 use rustc_attr as attr;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::{error_code, struct_span_err, Applicability, Handler};
@@ -20,11 +25,6 @@ use rustc_session::parse::{feature_err, ParseSess};
 use rustc_span::edition::{Edition, ALL_EDITIONS};
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{Span, DUMMY_SP};
-use syntax::ast::{self, AttrItem, Attribute, MetaItem};
-use syntax::attr::HasAttrs;
-use syntax::mut_visit::*;
-use syntax::ptr::P;
-use syntax::util::map_in_place::MapInPlace;
 
 use smallvec::SmallVec;
 
diff --git a/src/librustc_parse/lexer/mod.rs b/src/librustc_parse/lexer/mod.rs
index 2cd8b0b90c1..f7fb704fcbc 100644
--- a/src/librustc_parse/lexer/mod.rs
+++ b/src/librustc_parse/lexer/mod.rs
@@ -1,3 +1,5 @@
+use rustc_ast::token::{self, Token, TokenKind};
+use rustc_ast::util::comments;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::{error_code, DiagnosticBuilder, FatalError};
 use rustc_lexer::unescape;
@@ -5,8 +7,6 @@ use rustc_lexer::Base;
 use rustc_session::parse::ParseSess;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{BytePos, Pos, Span};
-use syntax::token::{self, Token, TokenKind};
-use syntax::util::comments;
 
 use log::debug;
 use std::char;
diff --git a/src/librustc_parse/lexer/tokentrees.rs b/src/librustc_parse/lexer/tokentrees.rs
index e87dde8863c..6c0acd0302f 100644
--- a/src/librustc_parse/lexer/tokentrees.rs
+++ b/src/librustc_parse/lexer/tokentrees.rs
@@ -1,15 +1,15 @@
 use super::{StringReader, UnmatchedBrace};
 
-use rustc_ast_pretty::pprust::token_to_string;
-use rustc_data_structures::fx::FxHashMap;
-use rustc_errors::PResult;
-use rustc_span::Span;
-use syntax::token::{self, Token};
-use syntax::tokenstream::{
+use rustc_ast::token::{self, Token};
+use rustc_ast::tokenstream::{
     DelimSpan,
     IsJoint::{self, *},
     TokenStream, TokenTree, TreeAndJoint,
 };
+use rustc_ast_pretty::pprust::token_to_string;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_errors::PResult;
+use rustc_span::Span;
 
 impl<'a> StringReader<'a> {
     crate fn into_token_trees(self) -> (PResult<'a, TokenStream>, Vec<UnmatchedBrace>) {
diff --git a/src/librustc_parse/lib.rs b/src/librustc_parse/lib.rs
index 077c171acca..25f9f8fd3ad 100644
--- a/src/librustc_parse/lib.rs
+++ b/src/librustc_parse/lib.rs
@@ -3,14 +3,14 @@
 #![feature(bool_to_option)]
 #![feature(crate_visibility_modifier)]
 
+use rustc_ast::ast;
+use rustc_ast::token::{self, Nonterminal, Token};
+use rustc_ast::tokenstream::{self, TokenStream, TokenTree};
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::{Diagnostic, FatalError, Level, PResult};
 use rustc_session::parse::ParseSess;
 use rustc_span::{FileName, SourceFile, Span};
-use syntax::ast;
-use syntax::token::{self, Nonterminal, Token};
-use syntax::tokenstream::{self, TokenStream, TokenTree};
 
 use std::path::{Path, PathBuf};
 use std::str;
diff --git a/src/librustc_parse/parser/attr.rs b/src/librustc_parse/parser/attr.rs
index 905f6bef58e..93de5a33fe3 100644
--- a/src/librustc_parse/parser/attr.rs
+++ b/src/librustc_parse/parser/attr.rs
@@ -1,11 +1,11 @@
 use super::{Parser, PathStyle, TokenType};
+use rustc_ast::ast;
+use rustc_ast::attr;
+use rustc_ast::token::{self, Nonterminal};
+use rustc_ast::util::comments;
 use rustc_ast_pretty::pprust;
 use rustc_errors::PResult;
 use rustc_span::{Span, Symbol};
-use syntax::ast;
-use syntax::attr;
-use syntax::token::{self, Nonterminal};
-use syntax::util::comments;
 
 use log::debug;
 
diff --git a/src/librustc_parse/parser/diagnostics.rs b/src/librustc_parse/parser/diagnostics.rs
index 00f5fb97052..c27b429563a 100644
--- a/src/librustc_parse/parser/diagnostics.rs
+++ b/src/librustc_parse/parser/diagnostics.rs
@@ -1,6 +1,13 @@
 use super::ty::AllowPlus;
 use super::{BlockMode, Parser, PathStyle, SemiColonMode, SeqSep, TokenExpectType, TokenType};
 
+use rustc_ast::ast::{
+    self, BinOpKind, BindingMode, BlockCheckMode, Expr, ExprKind, Ident, Item, Param,
+};
+use rustc_ast::ast::{AttrVec, ItemKind, Mutability, Pat, PatKind, PathSegment, QSelf, Ty, TyKind};
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, TokenKind};
+use rustc_ast::util::parser::AssocOp;
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::{pluralize, struct_span_err};
@@ -8,13 +15,6 @@ use rustc_errors::{Applicability, DiagnosticBuilder, Handler, PResult};
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::kw;
 use rustc_span::{MultiSpan, Span, SpanSnippetError, DUMMY_SP};
-use syntax::ast::{
-    self, BinOpKind, BindingMode, BlockCheckMode, Expr, ExprKind, Ident, Item, Param,
-};
-use syntax::ast::{AttrVec, ItemKind, Mutability, Pat, PatKind, PathSegment, QSelf, Ty, TyKind};
-use syntax::ptr::P;
-use syntax::token::{self, TokenKind};
-use syntax::util::parser::AssocOp;
 
 use log::{debug, trace};
 use std::mem;
diff --git a/src/librustc_parse/parser/expr.rs b/src/librustc_parse/parser/expr.rs
index 71ca8fba0b4..703fbbb6a6e 100644
--- a/src/librustc_parse/parser/expr.rs
+++ b/src/librustc_parse/parser/expr.rs
@@ -4,19 +4,19 @@ use super::{BlockMode, Parser, PathStyle, Restrictions, TokenType};
 use super::{SemiColonMode, SeqSep, TokenExpectType};
 use crate::maybe_recover_from_interpolated_ty_qpath;
 
+use rustc_ast::ast::{self, AttrStyle, AttrVec, CaptureBy, Field, Ident, Lit, DUMMY_NODE_ID};
+use rustc_ast::ast::{AnonConst, BinOp, BinOpKind, FnDecl, FnRetTy, Mac, Param, Ty, TyKind, UnOp};
+use rustc_ast::ast::{Arm, Async, BlockCheckMode, Expr, ExprKind, Label, Movability, RangeLimits};
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, Token, TokenKind};
+use rustc_ast::util::classify;
+use rustc_ast::util::literal::LitError;
+use rustc_ast::util::parser::{prec_let_scrutinee_needs_par, AssocOp, Fixity};
 use rustc_ast_pretty::pprust;
 use rustc_errors::{Applicability, PResult};
 use rustc_span::source_map::{self, Span, Spanned};
 use rustc_span::symbol::{kw, sym, Symbol};
 use std::mem;
-use syntax::ast::{self, AttrStyle, AttrVec, CaptureBy, Field, Ident, Lit, DUMMY_NODE_ID};
-use syntax::ast::{AnonConst, BinOp, BinOpKind, FnDecl, FnRetTy, Mac, Param, Ty, TyKind, UnOp};
-use syntax::ast::{Arm, Async, BlockCheckMode, Expr, ExprKind, Label, Movability, RangeLimits};
-use syntax::ptr::P;
-use syntax::token::{self, Token, TokenKind};
-use syntax::util::classify;
-use syntax::util::literal::LitError;
-use syntax::util::parser::{prec_let_scrutinee_needs_par, AssocOp, Fixity};
 
 /// Possibly accepts an `token::Interpolated` expression (a pre-parsed expression
 /// dropped into the token stream, which happens while parsing the result of
diff --git a/src/librustc_parse/parser/generics.rs b/src/librustc_parse/parser/generics.rs
index d5ad1e90d16..481dde0a35c 100644
--- a/src/librustc_parse/parser/generics.rs
+++ b/src/librustc_parse/parser/generics.rs
@@ -1,9 +1,9 @@
 use super::Parser;
 
+use rustc_ast::ast::{self, Attribute, GenericBounds, GenericParam, GenericParamKind, WhereClause};
+use rustc_ast::token;
 use rustc_errors::PResult;
 use rustc_span::symbol::{kw, sym};
-use syntax::ast::{self, Attribute, GenericBounds, GenericParam, GenericParamKind, WhereClause};
-use syntax::token;
 
 impl<'a> Parser<'a> {
     /// Parses bounds of a lifetime parameter `BOUND + BOUND + BOUND`, possibly with trailing `+`.
diff --git a/src/librustc_parse/parser/item.rs b/src/librustc_parse/parser/item.rs
index ef4246609da..692ea0cf5bf 100644
--- a/src/librustc_parse/parser/item.rs
+++ b/src/librustc_parse/parser/item.rs
@@ -4,19 +4,23 @@ use super::{FollowedByType, Parser, PathStyle};
 
 use crate::maybe_whole;
 
+use rustc_ast::ast::{self, AttrStyle, AttrVec, Attribute, Ident, DUMMY_NODE_ID};
+use rustc_ast::ast::{AssocItem, AssocItemKind, ForeignItemKind, Item, ItemKind};
+use rustc_ast::ast::{
+    Async, Const, Defaultness, IsAuto, PathSegment, Unsafe, UseTree, UseTreeKind,
+};
+use rustc_ast::ast::{
+    BindingMode, Block, FnDecl, FnSig, Mac, MacArgs, MacDelimiter, Param, SelfKind,
+};
+use rustc_ast::ast::{EnumDef, Generics, StructField, TraitRef, Ty, TyKind, Variant, VariantData};
+use rustc_ast::ast::{FnHeader, ForeignItem, Mutability, Visibility, VisibilityKind};
+use rustc_ast::ptr::P;
+use rustc_ast::token;
+use rustc_ast::tokenstream::{DelimSpan, TokenStream, TokenTree};
 use rustc_ast_pretty::pprust;
 use rustc_errors::{struct_span_err, Applicability, PResult, StashKey};
 use rustc_span::source_map::{self, Span};
 use rustc_span::symbol::{kw, sym, Symbol};
-use syntax::ast::{self, AttrStyle, AttrVec, Attribute, Ident, DUMMY_NODE_ID};
-use syntax::ast::{AssocItem, AssocItemKind, ForeignItemKind, Item, ItemKind};
-use syntax::ast::{Async, Const, Defaultness, IsAuto, PathSegment, Unsafe, UseTree, UseTreeKind};
-use syntax::ast::{BindingMode, Block, FnDecl, FnSig, Mac, MacArgs, MacDelimiter, Param, SelfKind};
-use syntax::ast::{EnumDef, Generics, StructField, TraitRef, Ty, TyKind, Variant, VariantData};
-use syntax::ast::{FnHeader, ForeignItem, Mutability, Visibility, VisibilityKind};
-use syntax::ptr::P;
-use syntax::token;
-use syntax::tokenstream::{DelimSpan, TokenStream, TokenTree};
 
 use log::debug;
 use std::mem;
diff --git a/src/librustc_parse/parser/mod.rs b/src/librustc_parse/parser/mod.rs
index 58a03ee2a74..63a19d5de54 100644
--- a/src/librustc_parse/parser/mod.rs
+++ b/src/librustc_parse/parser/mod.rs
@@ -16,19 +16,21 @@ use crate::lexer::UnmatchedBrace;
 use crate::{Directory, DirectoryOwnership};
 
 use log::debug;
+use rustc_ast::ast::DUMMY_NODE_ID;
+use rustc_ast::ast::{self, AttrStyle, AttrVec, Const, CrateSugar, Extern, Ident, Unsafe};
+use rustc_ast::ast::{
+    Async, MacArgs, MacDelimiter, Mutability, StrLit, Visibility, VisibilityKind,
+};
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, DelimToken, Token, TokenKind};
+use rustc_ast::tokenstream::{self, DelimSpan, TokenStream, TokenTree, TreeAndJoint};
+use rustc_ast::util::comments::{doc_comment_style, strip_doc_comment_decoration};
 use rustc_ast_pretty::pprust;
 use rustc_errors::{struct_span_err, Applicability, DiagnosticBuilder, FatalError, PResult};
 use rustc_session::parse::ParseSess;
 use rustc_span::source_map::respan;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::{FileName, Span, DUMMY_SP};
-use syntax::ast::DUMMY_NODE_ID;
-use syntax::ast::{self, AttrStyle, AttrVec, Const, CrateSugar, Extern, Ident, Unsafe};
-use syntax::ast::{Async, MacArgs, MacDelimiter, Mutability, StrLit, Visibility, VisibilityKind};
-use syntax::ptr::P;
-use syntax::token::{self, DelimToken, Token, TokenKind};
-use syntax::tokenstream::{self, DelimSpan, TokenStream, TokenTree, TreeAndJoint};
-use syntax::util::comments::{doc_comment_style, strip_doc_comment_decoration};
 
 use std::path::PathBuf;
 use std::{cmp, mem, slice};
diff --git a/src/librustc_parse/parser/module.rs b/src/librustc_parse/parser/module.rs
index 9dba813c9a7..4e9a9a5021b 100644
--- a/src/librustc_parse/parser/module.rs
+++ b/src/librustc_parse/parser/module.rs
@@ -4,12 +4,12 @@ use super::Parser;
 
 use crate::{new_sub_parser_from_file, DirectoryOwnership};
 
+use rustc_ast::ast::{self, Attribute, Crate, Ident, ItemKind, Mod};
+use rustc_ast::attr;
+use rustc_ast::token::{self, TokenKind};
 use rustc_errors::PResult;
 use rustc_span::source_map::{FileName, SourceMap, Span, DUMMY_SP};
 use rustc_span::symbol::sym;
-use syntax::ast::{self, Attribute, Crate, Ident, ItemKind, Mod};
-use syntax::attr;
-use syntax::token::{self, TokenKind};
 
 use std::path::{self, Path, PathBuf};
 
diff --git a/src/librustc_parse/parser/pat.rs b/src/librustc_parse/parser/pat.rs
index 4dc2f775173..f3794747397 100644
--- a/src/librustc_parse/parser/pat.rs
+++ b/src/librustc_parse/parser/pat.rs
@@ -1,14 +1,16 @@
 use super::{Parser, PathStyle};
 use crate::{maybe_recover_from_interpolated_ty_qpath, maybe_whole};
+use rustc_ast::ast::{
+    self, AttrVec, Attribute, FieldPat, Mac, Pat, PatKind, RangeEnd, RangeSyntax,
+};
+use rustc_ast::ast::{BindingMode, Expr, ExprKind, Ident, Mutability, Path, QSelf};
+use rustc_ast::mut_visit::{noop_visit_mac, noop_visit_pat, MutVisitor};
+use rustc_ast::ptr::P;
+use rustc_ast::token;
 use rustc_ast_pretty::pprust;
 use rustc_errors::{struct_span_err, Applicability, DiagnosticBuilder, PResult};
 use rustc_span::source_map::{respan, Span, Spanned};
 use rustc_span::symbol::{kw, sym};
-use syntax::ast::{self, AttrVec, Attribute, FieldPat, Mac, Pat, PatKind, RangeEnd, RangeSyntax};
-use syntax::ast::{BindingMode, Expr, ExprKind, Ident, Mutability, Path, QSelf};
-use syntax::mut_visit::{noop_visit_mac, noop_visit_pat, MutVisitor};
-use syntax::ptr::P;
-use syntax::token;
 
 type Expected = Option<&'static str>;
 
diff --git a/src/librustc_parse/parser/path.rs b/src/librustc_parse/parser/path.rs
index 1db920625e3..6a71ebe2183 100644
--- a/src/librustc_parse/parser/path.rs
+++ b/src/librustc_parse/parser/path.rs
@@ -1,14 +1,16 @@
 use super::ty::{AllowPlus, RecoverQPath};
 use super::{Parser, TokenType};
 use crate::maybe_whole;
+use rustc_ast::ast::{
+    self, AngleBracketedArgs, Ident, ParenthesizedArgs, Path, PathSegment, QSelf,
+};
+use rustc_ast::ast::{
+    AnonConst, AssocTyConstraint, AssocTyConstraintKind, BlockCheckMode, GenericArg,
+};
+use rustc_ast::token::{self, Token};
 use rustc_errors::{pluralize, Applicability, PResult};
 use rustc_span::source_map::{BytePos, Span};
 use rustc_span::symbol::{kw, sym};
-use syntax::ast::{self, AngleBracketedArgs, Ident, ParenthesizedArgs, Path, PathSegment, QSelf};
-use syntax::ast::{
-    AnonConst, AssocTyConstraint, AssocTyConstraintKind, BlockCheckMode, GenericArg,
-};
-use syntax::token::{self, Token};
 
 use log::debug;
 use std::mem;
diff --git a/src/librustc_parse/parser/stmt.rs b/src/librustc_parse/parser/stmt.rs
index 9073e131f70..e0d8699442f 100644
--- a/src/librustc_parse/parser/stmt.rs
+++ b/src/librustc_parse/parser/stmt.rs
@@ -6,15 +6,15 @@ use super::{BlockMode, Parser, Restrictions, SemiColonMode};
 use crate::maybe_whole;
 use crate::DirectoryOwnership;
 
+use rustc_ast::ast;
+use rustc_ast::ast::{AttrStyle, AttrVec, Attribute, Mac, MacStmtStyle};
+use rustc_ast::ast::{Block, BlockCheckMode, Expr, ExprKind, Local, Stmt, StmtKind, DUMMY_NODE_ID};
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, TokenKind};
+use rustc_ast::util::classify;
 use rustc_errors::{Applicability, PResult};
 use rustc_span::source_map::{BytePos, Span};
 use rustc_span::symbol::{kw, sym};
-use syntax::ast;
-use syntax::ast::{AttrStyle, AttrVec, Attribute, Mac, MacStmtStyle};
-use syntax::ast::{Block, BlockCheckMode, Expr, ExprKind, Local, Stmt, StmtKind, DUMMY_NODE_ID};
-use syntax::ptr::P;
-use syntax::token::{self, TokenKind};
-use syntax::util::classify;
 
 use std::mem;
 
diff --git a/src/librustc_parse/parser/ty.rs b/src/librustc_parse/parser/ty.rs
index 7b2fdebcfb9..8d100c344fa 100644
--- a/src/librustc_parse/parser/ty.rs
+++ b/src/librustc_parse/parser/ty.rs
@@ -2,16 +2,16 @@ use super::{Parser, PathStyle, TokenType};
 
 use crate::{maybe_recover_from_interpolated_ty_qpath, maybe_whole};
 
+use rustc_ast::ast::{self, BareFnTy, FnRetTy, GenericParam, Lifetime, MutTy, Ty, TyKind};
+use rustc_ast::ast::{
+    GenericBound, GenericBounds, PolyTraitRef, TraitBoundModifier, TraitObjectSyntax,
+};
+use rustc_ast::ast::{Mac, Mutability};
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, Token, TokenKind};
 use rustc_errors::{pluralize, struct_span_err, Applicability, PResult};
 use rustc_span::source_map::Span;
 use rustc_span::symbol::{kw, sym};
-use syntax::ast::{self, BareFnTy, FnRetTy, GenericParam, Lifetime, MutTy, Ty, TyKind};
-use syntax::ast::{
-    GenericBound, GenericBounds, PolyTraitRef, TraitBoundModifier, TraitObjectSyntax,
-};
-use syntax::ast::{Mac, Mutability};
-use syntax::ptr::P;
-use syntax::token::{self, Token, TokenKind};
 
 /// Any `?` or `?const` modifiers that appear at the start of a bound.
 struct BoundModifiers {
diff --git a/src/librustc_parse/validate_attr.rs b/src/librustc_parse/validate_attr.rs
index f5e47608d58..029aa5ed2ba 100644
--- a/src/librustc_parse/validate_attr.rs
+++ b/src/librustc_parse/validate_attr.rs
@@ -2,13 +2,13 @@
 
 use crate::parse_in;
 
+use rustc_ast::ast::{self, Attribute, MacArgs, MacDelimiter, MetaItem, MetaItemKind};
+use rustc_ast::tokenstream::DelimSpan;
 use rustc_errors::{Applicability, PResult};
 use rustc_feature::{AttributeTemplate, BUILTIN_ATTRIBUTE_MAP};
 use rustc_session::lint::builtin::ILL_FORMED_ATTRIBUTE_INPUT;
 use rustc_session::parse::ParseSess;
 use rustc_span::{sym, Symbol};
-use syntax::ast::{self, Attribute, MacArgs, MacDelimiter, MetaItem, MetaItemKind};
-use syntax::tokenstream::DelimSpan;
 
 pub fn check_meta(sess: &ParseSess, attr: &Attribute) {
     if attr.is_doc_comment() {
diff --git a/src/librustc_passes/Cargo.toml b/src/librustc_passes/Cargo.toml
index 62dee847e4c..af8e7a5b71e 100644
--- a/src/librustc_passes/Cargo.toml
+++ b/src/librustc_passes/Cargo.toml
@@ -20,5 +20,5 @@ rustc_index = { path = "../librustc_index" }
 rustc_infer = { path = "../librustc_infer" }
 rustc_session = { path = "../librustc_session" }
 rustc_target = { path = "../librustc_target" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
diff --git a/src/librustc_passes/check_attr.rs b/src/librustc_passes/check_attr.rs
index 5cabf3c0262..f1ed074d6ab 100644
--- a/src/librustc_passes/check_attr.rs
+++ b/src/librustc_passes/check_attr.rs
@@ -8,6 +8,8 @@ use rustc::hir::map::Map;
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
 
+use rustc_ast::ast::{Attribute, NestedMetaItem};
+use rustc_ast::attr;
 use rustc_errors::struct_span_err;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
@@ -19,8 +21,6 @@ use rustc_session::lint::builtin::{CONFLICTING_REPR_HINTS, UNUSED_ATTRIBUTES};
 use rustc_session::parse::feature_err;
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::ast::{Attribute, NestedMetaItem};
-use syntax::attr;
 
 fn target_from_impl_item<'tcx>(tcx: TyCtxt<'tcx>, impl_item: &hir::ImplItem<'_>) -> Target {
     match impl_item.kind {
diff --git a/src/librustc_passes/check_const.rs b/src/librustc_passes/check_const.rs
index d713a82fd88..53e8213ae48 100644
--- a/src/librustc_passes/check_const.rs
+++ b/src/librustc_passes/check_const.rs
@@ -13,12 +13,12 @@ use rustc::session::config::nightly_options;
 use rustc::session::parse::feature_err;
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast::Mutability;
 use rustc_errors::struct_span_err;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
 use rustc_span::{sym, Span, Symbol};
-use syntax::ast::Mutability;
 
 use std::fmt;
 
diff --git a/src/librustc_passes/dead.rs b/src/librustc_passes/dead.rs
index e2749c7bd7c..bcf9fd5a535 100644
--- a/src/librustc_passes/dead.rs
+++ b/src/librustc_passes/dead.rs
@@ -15,8 +15,8 @@ use rustc_hir::itemlikevisit::ItemLikeVisitor;
 use rustc_hir::{Node, PatKind, TyKind};
 use rustc_session::lint;
 
+use rustc_ast::{ast, attr};
 use rustc_span::symbol::sym;
-use syntax::{ast, attr};
 
 // Any local node that may call something in its body block should be
 // explored. For example, if it's a live Node::Item that is a
diff --git a/src/librustc_passes/diagnostic_items.rs b/src/librustc_passes/diagnostic_items.rs
index 5e831b558a3..ae23e9e35f9 100644
--- a/src/librustc_passes/diagnostic_items.rs
+++ b/src/librustc_passes/diagnostic_items.rs
@@ -11,12 +11,12 @@
 
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_hir::itemlikevisit::ItemLikeVisitor;
 use rustc_span::symbol::{sym, Symbol};
-use syntax::ast;
 
 struct DiagnosticItemCollector<'tcx> {
     // items from this crate
diff --git a/src/librustc_passes/entry.rs b/src/librustc_passes/entry.rs
index 28fa64b6cb7..f2239ad16ee 100644
--- a/src/librustc_passes/entry.rs
+++ b/src/librustc_passes/entry.rs
@@ -3,14 +3,14 @@ use rustc::session::config::EntryFnType;
 use rustc::session::{config, Session};
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
+use rustc_ast::attr;
+use rustc_ast::entry::EntryPointType;
 use rustc_errors::struct_span_err;
 use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_INDEX, LOCAL_CRATE};
 use rustc_hir::itemlikevisit::ItemLikeVisitor;
 use rustc_hir::{HirId, ImplItem, Item, ItemKind, TraitItem};
 use rustc_span::symbol::sym;
 use rustc_span::{Span, DUMMY_SP};
-use syntax::attr;
-use syntax::entry::EntryPointType;
 
 struct EntryContext<'a, 'tcx> {
     session: &'a Session,
diff --git a/src/librustc_passes/hir_stats.rs b/src/librustc_passes/hir_stats.rs
index c6c201fa38e..c819809041f 100644
--- a/src/librustc_passes/hir_stats.rs
+++ b/src/librustc_passes/hir_stats.rs
@@ -4,13 +4,13 @@
 
 use rustc::hir::map::Map;
 use rustc::util::common::to_readable_str;
+use rustc_ast::ast::{self, AttrId, NodeId};
+use rustc_ast::visit as ast_visit;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 use rustc_hir::intravisit as hir_visit;
 use rustc_hir::HirId;
 use rustc_span::Span;
-use syntax::ast::{self, AttrId, NodeId};
-use syntax::visit as ast_visit;
 
 #[derive(Copy, Clone, PartialEq, Eq, Hash)]
 enum Id {
diff --git a/src/librustc_passes/layout_test.rs b/src/librustc_passes/layout_test.rs
index be3e1f47382..9f6598a0ec1 100644
--- a/src/librustc_passes/layout_test.rs
+++ b/src/librustc_passes/layout_test.rs
@@ -7,12 +7,12 @@ use rustc::ty::layout::TyLayout;
 use rustc::ty::ParamEnv;
 use rustc::ty::Ty;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast::Attribute;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_hir::itemlikevisit::ItemLikeVisitor;
 use rustc_hir::ItemKind;
 use rustc_span::symbol::sym;
-use syntax::ast::Attribute;
 
 pub fn test_layout(tcx: TyCtxt<'_>) {
     if tcx.features().rustc_attrs {
diff --git a/src/librustc_passes/lib_features.rs b/src/librustc_passes/lib_features.rs
index 2e306a1b4f2..172d7e7628e 100644
--- a/src/librustc_passes/lib_features.rs
+++ b/src/librustc_passes/lib_features.rs
@@ -8,12 +8,12 @@ use rustc::hir::map::Map;
 use rustc::middle::lib_features::LibFeatures;
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast::{Attribute, MetaItem, MetaItemKind};
 use rustc_errors::struct_span_err;
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
 use rustc_span::symbol::Symbol;
 use rustc_span::{sym, Span};
-use syntax::ast::{Attribute, MetaItem, MetaItemKind};
 
 fn new_lib_features() -> LibFeatures {
     LibFeatures { stable: Default::default(), unstable: Default::default() }
diff --git a/src/librustc_passes/liveness.rs b/src/librustc_passes/liveness.rs
index f0bb3cd08ad..43b615dee98 100644
--- a/src/librustc_passes/liveness.rs
+++ b/src/librustc_passes/liveness.rs
@@ -100,6 +100,7 @@ use rustc::hir::map::Map;
 use rustc::lint;
 use rustc::ty::query::Providers;
 use rustc::ty::{self, TyCtxt};
+use rustc_ast::ast;
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_errors::Applicability;
 use rustc_hir as hir;
@@ -109,7 +110,6 @@ use rustc_hir::intravisit::{self, FnKind, NestedVisitorMap, Visitor};
 use rustc_hir::{Expr, HirId, HirIdMap, HirIdSet, Node};
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::ast;
 
 use std::collections::VecDeque;
 use std::io;
diff --git a/src/librustc_passes/region.rs b/src/librustc_passes/region.rs
index d0f49fdcc75..e636144794a 100644
--- a/src/librustc_passes/region.rs
+++ b/src/librustc_passes/region.rs
@@ -10,6 +10,7 @@ use rustc::hir::map::Map;
 use rustc::middle::region::*;
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
+use rustc_ast::walk_list;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
@@ -18,7 +19,6 @@ use rustc_hir::{Arm, Block, Expr, Local, Node, Pat, PatKind, Stmt};
 use rustc_index::vec::Idx;
 use rustc_span::source_map;
 use rustc_span::Span;
-use syntax::walk_list;
 
 use std::mem;
 
diff --git a/src/librustc_passes/stability.rs b/src/librustc_passes/stability.rs
index 99fbac4568e..5eae935f050 100644
--- a/src/librustc_passes/stability.rs
+++ b/src/librustc_passes/stability.rs
@@ -9,6 +9,7 @@ use rustc::session::parse::feature_err;
 use rustc::session::Session;
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast::Attribute;
 use rustc_attr::{self as attr, ConstStability, Stability};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::struct_span_err;
@@ -20,7 +21,6 @@ use rustc_hir::{Generics, HirId, Item, StructField, Variant};
 use rustc_infer::traits::misc::can_type_implement_copy;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
-use syntax::ast::Attribute;
 
 use std::cmp::Ordering;
 use std::mem::replace;
diff --git a/src/librustc_plugin_impl/Cargo.toml b/src/librustc_plugin_impl/Cargo.toml
index b1c09ee1953..89313072590 100644
--- a/src/librustc_plugin_impl/Cargo.toml
+++ b/src/librustc_plugin_impl/Cargo.toml
@@ -16,5 +16,5 @@ rustc_errors = { path = "../librustc_errors" }
 rustc_hir = { path = "../librustc_hir" }
 rustc_lint = { path = "../librustc_lint" }
 rustc_metadata = { path = "../librustc_metadata" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
diff --git a/src/librustc_plugin_impl/build.rs b/src/librustc_plugin_impl/build.rs
index c4b644031d3..03e58d758c5 100644
--- a/src/librustc_plugin_impl/build.rs
+++ b/src/librustc_plugin_impl/build.rs
@@ -2,12 +2,12 @@
 
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
+use rustc_ast::attr;
 use rustc_hir as hir;
 use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
 use rustc_hir::itemlikevisit::ItemLikeVisitor;
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::attr;
 
 struct RegistrarFinder {
     registrars: Vec<(hir::HirId, Span)>,
diff --git a/src/librustc_plugin_impl/load.rs b/src/librustc_plugin_impl/load.rs
index 84549c0dd45..9bd9bcb25ba 100644
--- a/src/librustc_plugin_impl/load.rs
+++ b/src/librustc_plugin_impl/load.rs
@@ -3,11 +3,11 @@
 use crate::Registry;
 use rustc::middle::cstore::MetadataLoader;
 use rustc::session::Session;
+use rustc_ast::ast::{Crate, Ident};
 use rustc_errors::struct_span_err;
 use rustc_metadata::locator;
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::ast::{Crate, Ident};
 
 use std::borrow::ToOwned;
 use std::env;
diff --git a/src/librustc_privacy/Cargo.toml b/src/librustc_privacy/Cargo.toml
index c55ae44a241..6d1272c117b 100644
--- a/src/librustc_privacy/Cargo.toml
+++ b/src/librustc_privacy/Cargo.toml
@@ -14,7 +14,7 @@ rustc_attr = { path = "../librustc_attr" }
 rustc_errors = { path = "../librustc_errors" }
 rustc_hir = { path = "../librustc_hir" }
 rustc_typeck = { path = "../librustc_typeck" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 log = "0.4"
diff --git a/src/librustc_privacy/lib.rs b/src/librustc_privacy/lib.rs
index ef1e99c5a64..8edadc44875 100644
--- a/src/librustc_privacy/lib.rs
+++ b/src/librustc_privacy/lib.rs
@@ -11,6 +11,7 @@ use rustc::ty::fold::TypeVisitor;
 use rustc::ty::query::Providers;
 use rustc::ty::subst::InternalSubsts;
 use rustc::ty::{self, GenericParamDefKind, TraitRef, Ty, TyCtxt, TypeFoldable};
+use rustc_ast::ast::Ident;
 use rustc_attr as attr;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::struct_span_err;
@@ -22,7 +23,6 @@ use rustc_hir::{AssocItemKind, HirIdSet, Node, PatKind};
 use rustc_span::hygiene::Transparency;
 use rustc_span::symbol::{kw, sym};
 use rustc_span::Span;
-use syntax::ast::Ident;
 
 use std::marker::PhantomData;
 use std::{cmp, fmt, mem};
diff --git a/src/librustc_resolve/Cargo.toml b/src/librustc_resolve/Cargo.toml
index 145a998fef1..11a3cedcc74 100644
--- a/src/librustc_resolve/Cargo.toml
+++ b/src/librustc_resolve/Cargo.toml
@@ -13,7 +13,7 @@ doctest = false
 [dependencies]
 bitflags = "1.2.1"
 log = "0.4"
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 arena = { path = "../libarena" }
 rustc = { path = "../librustc" }
 rustc_ast_lowering = { path = "../librustc_ast_lowering" }
diff --git a/src/librustc_resolve/build_reduced_graph.rs b/src/librustc_resolve/build_reduced_graph.rs
index 2a9e335e924..86816fd9f3a 100644
--- a/src/librustc_resolve/build_reduced_graph.rs
+++ b/src/librustc_resolve/build_reduced_graph.rs
@@ -20,6 +20,11 @@ use rustc::bug;
 use rustc::hir::exports::Export;
 use rustc::middle::cstore::CrateStore;
 use rustc::ty;
+use rustc_ast::ast::{self, Block, ForeignItem, ForeignItemKind, Item, ItemKind, NodeId};
+use rustc_ast::ast::{AssocItem, AssocItemKind, MetaItemKind, StmtKind};
+use rustc_ast::ast::{Ident, Name};
+use rustc_ast::token::{self, Token};
+use rustc_ast::visit::{self, AssocCtxt, Visitor};
 use rustc_attr as attr;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::{struct_span_err, Applicability};
@@ -32,11 +37,6 @@ use rustc_span::hygiene::{ExpnId, MacroKind};
 use rustc_span::source_map::{respan, Spanned};
 use rustc_span::symbol::{kw, sym};
 use rustc_span::{Span, DUMMY_SP};
-use syntax::ast::{self, Block, ForeignItem, ForeignItemKind, Item, ItemKind, NodeId};
-use syntax::ast::{AssocItem, AssocItemKind, MetaItemKind, StmtKind};
-use syntax::ast::{Ident, Name};
-use syntax::token::{self, Token};
-use syntax::visit::{self, AssocCtxt, Visitor};
 
 use log::debug;
 use std::cell::Cell;
diff --git a/src/librustc_resolve/check_unused.rs b/src/librustc_resolve/check_unused.rs
index 74154cb3df4..659a54b169b 100644
--- a/src/librustc_resolve/check_unused.rs
+++ b/src/librustc_resolve/check_unused.rs
@@ -27,13 +27,13 @@ use crate::imports::ImportDirectiveSubclass;
 use crate::Resolver;
 
 use rustc::{lint, ty};
+use rustc_ast::ast;
+use rustc_ast::node_id::NodeMap;
+use rustc_ast::visit::{self, Visitor};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::pluralize;
 use rustc_session::lint::BuiltinLintDiagnostics;
 use rustc_span::{MultiSpan, Span, DUMMY_SP};
-use syntax::ast;
-use syntax::node_id::NodeMap;
-use syntax::visit::{self, Visitor};
 
 struct UnusedImport<'a> {
     use_tree: &'a ast::UseTree,
diff --git a/src/librustc_resolve/def_collector.rs b/src/librustc_resolve/def_collector.rs
index 30089633689..2e687c88941 100644
--- a/src/librustc_resolve/def_collector.rs
+++ b/src/librustc_resolve/def_collector.rs
@@ -1,13 +1,13 @@
 use log::debug;
 use rustc::hir::map::definitions::*;
+use rustc_ast::ast::*;
+use rustc_ast::token::{self, Token};
+use rustc_ast::visit;
 use rustc_expand::expand::AstFragment;
 use rustc_hir::def_id::DefIndex;
 use rustc_span::hygiene::ExpnId;
 use rustc_span::symbol::{kw, sym};
 use rustc_span::Span;
-use syntax::ast::*;
-use syntax::token::{self, Token};
-use syntax::visit;
 
 crate fn collect_definitions(
     definitions: &mut Definitions,
diff --git a/src/librustc_resolve/diagnostics.rs b/src/librustc_resolve/diagnostics.rs
index d08ae3040bd..6d9c78cddf2 100644
--- a/src/librustc_resolve/diagnostics.rs
+++ b/src/librustc_resolve/diagnostics.rs
@@ -4,6 +4,8 @@ use log::debug;
 use rustc::bug;
 use rustc::session::Session;
 use rustc::ty::{self, DefIdTree};
+use rustc_ast::ast::{self, Ident, Path};
+use rustc_ast::util::lev_distance::find_best_match_for_name;
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::{struct_span_err, Applicability, DiagnosticBuilder};
@@ -15,8 +17,6 @@ use rustc_span::hygiene::MacroKind;
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::{kw, Symbol};
 use rustc_span::{BytePos, MultiSpan, Span};
-use syntax::ast::{self, Ident, Path};
-use syntax::util::lev_distance::find_best_match_for_name;
 
 use crate::imports::{ImportDirective, ImportDirectiveSubclass, ImportResolver};
 use crate::path_names_to_string;
diff --git a/src/librustc_resolve/imports.rs b/src/librustc_resolve/imports.rs
index 3926849e7ca..9198c74d89a 100644
--- a/src/librustc_resolve/imports.rs
+++ b/src/librustc_resolve/imports.rs
@@ -15,6 +15,9 @@ use rustc::hir::exports::Export;
 use rustc::lint::builtin::{PUB_USE_OF_PRIVATE_EXTERN_CRATE, UNUSED_IMPORTS};
 use rustc::ty;
 use rustc::{bug, span_bug};
+use rustc_ast::ast::{Ident, Name, NodeId};
+use rustc_ast::unwrap_or;
+use rustc_ast::util::lev_distance::find_best_match_for_name;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::ptr_key::PtrKey;
 use rustc_errors::{pluralize, struct_span_err, Applicability};
@@ -25,9 +28,6 @@ use rustc_session::DiagnosticMessageId;
 use rustc_span::hygiene::ExpnId;
 use rustc_span::symbol::kw;
 use rustc_span::{MultiSpan, Span};
-use syntax::ast::{Ident, Name, NodeId};
-use syntax::unwrap_or;
-use syntax::util::lev_distance::find_best_match_for_name;
 
 use log::*;
 
diff --git a/src/librustc_resolve/late.rs b/src/librustc_resolve/late.rs
index c062b7dbe64..e5aa9c7d896 100644
--- a/src/librustc_resolve/late.rs
+++ b/src/librustc_resolve/late.rs
@@ -12,6 +12,11 @@ use crate::{Module, ModuleOrUniformRoot, NameBindingKind, ParentScope, PathResul
 use crate::{ResolutionError, Resolver, Segment, UseError};
 
 use rustc::{bug, lint, span_bug};
+use rustc_ast::ast::*;
+use rustc_ast::ptr::P;
+use rustc_ast::util::lev_distance::find_best_match_for_name;
+use rustc_ast::visit::{self, AssocCtxt, FnCtxt, FnKind, Visitor};
+use rustc_ast::{unwrap_or, walk_list};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::DiagnosticId;
 use rustc_hir::def::Namespace::{self, *};
@@ -21,11 +26,6 @@ use rustc_hir::TraitCandidate;
 use rustc_span::symbol::{kw, sym};
 use rustc_span::Span;
 use smallvec::{smallvec, SmallVec};
-use syntax::ast::*;
-use syntax::ptr::P;
-use syntax::util::lev_distance::find_best_match_for_name;
-use syntax::visit::{self, AssocCtxt, FnCtxt, FnKind, Visitor};
-use syntax::{unwrap_or, walk_list};
 
 use log::debug;
 use std::collections::BTreeSet;
diff --git a/src/librustc_resolve/late/diagnostics.rs b/src/librustc_resolve/late/diagnostics.rs
index b7ac8fbe4eb..817a276ff3e 100644
--- a/src/librustc_resolve/late/diagnostics.rs
+++ b/src/librustc_resolve/late/diagnostics.rs
@@ -6,6 +6,8 @@ use crate::{CrateLint, Module, ModuleKind, ModuleOrUniformRoot};
 use crate::{PathResult, PathSource, Segment};
 
 use rustc::session::config::nightly_options;
+use rustc_ast::ast::{self, Expr, ExprKind, Ident, Item, ItemKind, NodeId, Path, Ty, TyKind};
+use rustc_ast::util::lev_distance::find_best_match_for_name;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
@@ -16,8 +18,6 @@ use rustc_hir::PrimTy;
 use rustc_span::hygiene::MacroKind;
 use rustc_span::symbol::{kw, sym};
 use rustc_span::Span;
-use syntax::ast::{self, Expr, ExprKind, Ident, Item, ItemKind, NodeId, Path, Ty, TyKind};
-use syntax::util::lev_distance::find_best_match_for_name;
 
 use log::debug;
 
diff --git a/src/librustc_resolve/late/lifetimes.rs b/src/librustc_resolve/late/lifetimes.rs
index 478757f0db7..463452e45ce 100644
--- a/src/librustc_resolve/late/lifetimes.rs
+++ b/src/librustc_resolve/late/lifetimes.rs
@@ -11,6 +11,9 @@ use rustc::lint;
 use rustc::middle::resolve_lifetime::*;
 use rustc::ty::{self, DefIdTree, GenericParamDefKind, TyCtxt};
 use rustc::{bug, span_bug};
+use rustc_ast::ast;
+use rustc_ast::attr;
+use rustc_ast::walk_list;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::{struct_span_err, Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
@@ -24,9 +27,6 @@ use rustc_span::Span;
 use std::borrow::Cow;
 use std::cell::Cell;
 use std::mem::{replace, take};
-use syntax::ast;
-use syntax::attr;
-use syntax::walk_list;
 
 use log::debug;
 
@@ -2719,7 +2719,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
             span_bug!(
                 lifetime_ref.span,
                 "lifetime reference not renumbered, \
-                 probably a bug in syntax::fold"
+                 probably a bug in rustc_ast::fold"
             );
         }
 
diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index 540877d22c2..44eba0d533d 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -23,6 +23,13 @@ use rustc::middle::cstore::{CrateStore, MetadataLoaderDyn};
 use rustc::span_bug;
 use rustc::ty::query::Providers;
 use rustc::ty::{self, DefIdTree, ResolverOutputs};
+use rustc_ast::ast::{self, FloatTy, Ident, IntTy, Name, NodeId, UintTy};
+use rustc_ast::ast::{Crate, CRATE_NODE_ID};
+use rustc_ast::ast::{ItemKind, Path};
+use rustc_ast::attr;
+use rustc_ast::node_id::{NodeMap, NodeSet};
+use rustc_ast::unwrap_or;
+use rustc_ast::visit::{self, Visitor};
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap};
 use rustc_data_structures::ptr_key::PtrKey;
@@ -41,13 +48,6 @@ use rustc_span::hygiene::{ExpnId, ExpnKind, MacroKind, SyntaxContext, Transparen
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{kw, sym};
 use rustc_span::{Span, DUMMY_SP};
-use syntax::ast::{self, FloatTy, Ident, IntTy, Name, NodeId, UintTy};
-use syntax::ast::{Crate, CRATE_NODE_ID};
-use syntax::ast::{ItemKind, Path};
-use syntax::attr;
-use syntax::node_id::{NodeMap, NodeSet};
-use syntax::unwrap_or;
-use syntax::visit::{self, Visitor};
 
 use log::debug;
 use std::cell::{Cell, RefCell};
diff --git a/src/librustc_resolve/macros.rs b/src/librustc_resolve/macros.rs
index 11139a3dc94..e11aec90669 100644
--- a/src/librustc_resolve/macros.rs
+++ b/src/librustc_resolve/macros.rs
@@ -10,6 +10,7 @@ use rustc::middle::stability;
 use rustc::session::parse::feature_err;
 use rustc::session::Session;
 use rustc::{lint, span_bug, ty};
+use rustc_ast::ast::{self, Ident, NodeId};
 use rustc_ast_pretty::pprust;
 use rustc_attr::{self as attr, StabilityLevel};
 use rustc_data_structures::fx::FxHashSet;
@@ -24,7 +25,6 @@ use rustc_span::edition::Edition;
 use rustc_span::hygiene::{self, ExpnData, ExpnId, ExpnKind};
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::{Span, DUMMY_SP};
-use syntax::ast::{self, Ident, NodeId};
 
 use rustc_data_structures::sync::Lrc;
 use rustc_span::hygiene::{AstPass, MacroKind};
diff --git a/src/librustc_save_analysis/Cargo.toml b/src/librustc_save_analysis/Cargo.toml
index bd433a71825..0f4cc4192b6 100644
--- a/src/librustc_save_analysis/Cargo.toml
+++ b/src/librustc_save_analysis/Cargo.toml
@@ -17,7 +17,7 @@ rustc_codegen_utils = { path = "../librustc_codegen_utils" }
 rustc_hir = { path = "../librustc_hir" }
 rustc_parse = { path = "../librustc_parse" }
 serde_json = "1"
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
 rls-data = "0.19"
 rls-span = "0.5"
diff --git a/src/librustc_save_analysis/dump_visitor.rs b/src/librustc_save_analysis/dump_visitor.rs
index b3a8657d80b..e8cd5ea832d 100644
--- a/src/librustc_save_analysis/dump_visitor.rs
+++ b/src/librustc_save_analysis/dump_visitor.rs
@@ -16,17 +16,17 @@
 use rustc::session::config::Input;
 use rustc::span_bug;
 use rustc::ty::{self, DefIdTree, TyCtxt};
+use rustc_ast::ast::{self, Attribute, NodeId, PatKind};
+use rustc_ast::ptr::P;
+use rustc_ast::token;
+use rustc_ast::visit::{self, Visitor};
+use rustc_ast::walk_list;
 use rustc_ast_pretty::pprust::{bounds_to_string, generic_params_to_string, ty_to_string};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir::def::{DefKind as HirDefKind, Res};
 use rustc_hir::def_id::DefId;
 use rustc_span::source_map::{respan, DUMMY_SP};
 use rustc_span::*;
-use syntax::ast::{self, Attribute, NodeId, PatKind};
-use syntax::ptr::P;
-use syntax::token;
-use syntax::visit::{self, Visitor};
-use syntax::walk_list;
 
 use std::env;
 use std::path::Path;
@@ -1260,7 +1260,7 @@ impl<'l, 'tcx> Visitor<'l> for DumpVisitor<'l, 'tcx> {
     }
 
     fn visit_item(&mut self, item: &'l ast::Item) {
-        use syntax::ast::ItemKind::*;
+        use rustc_ast::ast::ItemKind::*;
         self.process_macro_use(item.span);
         match item.kind {
             Use(ref use_tree) => {
diff --git a/src/librustc_save_analysis/lib.rs b/src/librustc_save_analysis/lib.rs
index b253559dd5c..dddee1c9926 100644
--- a/src/librustc_save_analysis/lib.rs
+++ b/src/librustc_save_analysis/lib.rs
@@ -13,6 +13,9 @@ use rustc::middle::privacy::AccessLevels;
 use rustc::session::config::{CrateType, Input, OutputType};
 use rustc::ty::{self, DefIdTree, TyCtxt};
 use rustc::{bug, span_bug};
+use rustc_ast::ast::{self, Attribute, NodeId, PatKind, DUMMY_NODE_ID};
+use rustc_ast::util::comments::strip_doc_comment_decoration;
+use rustc_ast::visit::{self, Visitor};
 use rustc_ast_pretty::pprust::{self, param_to_string, ty_to_string};
 use rustc_codegen_utils::link::{filename_for_metadata, out_filename};
 use rustc_hir as hir;
@@ -21,9 +24,6 @@ use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_hir::Node;
 use rustc_span::source_map::Spanned;
 use rustc_span::*;
-use syntax::ast::{self, Attribute, NodeId, PatKind, DUMMY_NODE_ID};
-use syntax::util::comments::strip_doc_comment_decoration;
-use syntax::visit::{self, Visitor};
 
 use std::cell::Cell;
 use std::default::Default;
diff --git a/src/librustc_save_analysis/sig.rs b/src/librustc_save_analysis/sig.rs
index 9670fb1e2c4..4e5ff9aa197 100644
--- a/src/librustc_save_analysis/sig.rs
+++ b/src/librustc_save_analysis/sig.rs
@@ -29,9 +29,9 @@ use crate::{id_from_def_id, id_from_node_id, SaveContext};
 
 use rls_data::{SigElement, Signature};
 
+use rustc_ast::ast::{self, Extern, NodeId};
 use rustc_ast_pretty::pprust;
 use rustc_hir::def::{DefKind, Res};
-use syntax::ast::{self, Extern, NodeId};
 
 pub fn item_signature(item: &ast::Item, scx: &SaveContext<'_, '_>) -> Option<Signature> {
     if !scx.config.signatures {
diff --git a/src/librustc_save_analysis/span_utils.rs b/src/librustc_save_analysis/span_utils.rs
index f904a0bb9f8..152435206fe 100644
--- a/src/librustc_save_analysis/span_utils.rs
+++ b/src/librustc_save_analysis/span_utils.rs
@@ -1,8 +1,8 @@
 use crate::generated_code;
 use rustc::session::Session;
+use rustc_ast::token::{self, TokenKind};
 use rustc_parse::lexer::{self, StringReader};
 use rustc_span::*;
-use syntax::token::{self, TokenKind};
 
 #[derive(Clone)]
 pub struct SpanUtils<'a> {
diff --git a/src/librustc_session/Cargo.toml b/src/librustc_session/Cargo.toml
index 30d1fd41984..3895d0f8061 100644
--- a/src/librustc_session/Cargo.toml
+++ b/src/librustc_session/Cargo.toml
@@ -19,4 +19,4 @@ rustc_span = { path = "../librustc_span" }
 rustc_index = { path = "../librustc_index" }
 rustc_fs_util = { path = "../librustc_fs_util" }
 num_cpus = "1.0"
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
diff --git a/src/librustc_session/lint.rs b/src/librustc_session/lint.rs
index 6d4f1ff5b48..3b79972ccbf 100644
--- a/src/librustc_session/lint.rs
+++ b/src/librustc_session/lint.rs
@@ -1,8 +1,8 @@
 pub use self::Level::*;
+use rustc_ast::node_id::{NodeId, NodeMap};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher, ToStableHashKey};
 use rustc_span::edition::Edition;
 use rustc_span::{sym, symbol::Ident, MultiSpan, Span, Symbol};
-use syntax::node_id::{NodeId, NodeMap};
 
 pub mod builtin;
 
diff --git a/src/librustc_session/parse.rs b/src/librustc_session/parse.rs
index 6d4f4be03ec..387d35422c4 100644
--- a/src/librustc_session/parse.rs
+++ b/src/librustc_session/parse.rs
@@ -2,6 +2,7 @@
 //! It also serves as an input to the parser itself.
 
 use crate::lint::{BufferedEarlyLint, BuiltinLintDiagnostics, Lint, LintId};
+use rustc_ast::node_id::NodeId;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::sync::{Lock, Lrc, Once};
 use rustc_errors::{emitter::SilentEmitter, ColorConfig, Handler};
@@ -11,7 +12,6 @@ use rustc_span::edition::Edition;
 use rustc_span::hygiene::ExpnId;
 use rustc_span::source_map::{FilePathMapping, SourceMap};
 use rustc_span::{MultiSpan, Span, Symbol};
-use syntax::node_id::NodeId;
 
 use std::path::PathBuf;
 use std::str;
diff --git a/src/librustc_traits/Cargo.toml b/src/librustc_traits/Cargo.toml
index a633d55bd8f..3fdbb4e6805 100644
--- a/src/librustc_traits/Cargo.toml
+++ b/src/librustc_traits/Cargo.toml
@@ -15,7 +15,7 @@ rustc_data_structures = { path = "../librustc_data_structures" }
 rustc_hir = { path = "../librustc_hir" }
 rustc_macros = { path = "../librustc_macros" }
 rustc_target = { path = "../librustc_target" }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
 chalk-engine = { version = "0.9.0", default-features=false }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
diff --git a/src/librustc_traits/lowering/mod.rs b/src/librustc_traits/lowering/mod.rs
index b77c603da9a..12325ad706f 100644
--- a/src/librustc_traits/lowering/mod.rs
+++ b/src/librustc_traits/lowering/mod.rs
@@ -9,12 +9,12 @@ use rustc::traits::{
 use rustc::ty::query::Providers;
 use rustc::ty::subst::{InternalSubsts, Subst};
 use rustc::ty::{self, List, TyCtxt};
+use rustc_ast::ast;
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::DefId;
 use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
 use rustc_span::symbol::sym;
-use syntax::ast;
 
 use std::iter;
 
diff --git a/src/librustc_typeck/Cargo.toml b/src/librustc_typeck/Cargo.toml
index 67ef91ab367..51a9b259c8f 100644
--- a/src/librustc_typeck/Cargo.toml
+++ b/src/librustc_typeck/Cargo.toml
@@ -20,7 +20,7 @@ rustc_errors = { path = "../librustc_errors" }
 rustc_hir = { path = "../librustc_hir" }
 rustc_target = { path = "../librustc_target" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
-syntax = { path = "../librustc_ast", package = "rustc_ast" }
+rustc_ast = { path = "../librustc_ast" }
 rustc_span = { path = "../librustc_span" }
 rustc_index = { path = "../librustc_index" }
 rustc_infer = { path = "../librustc_infer" }
diff --git a/src/librustc_typeck/astconv.rs b/src/librustc_typeck/astconv.rs
index a4213173d36..bef14d3f4a3 100644
--- a/src/librustc_typeck/astconv.rs
+++ b/src/librustc_typeck/astconv.rs
@@ -16,6 +16,8 @@ use rustc::session::{parse::feature_err, Session};
 use rustc::ty::subst::{self, InternalSubsts, Subst, SubstsRef};
 use rustc::ty::{self, Const, DefIdTree, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness};
 use rustc::ty::{GenericParamDef, GenericParamDefKind};
+use rustc_ast::ast;
+use rustc_ast::util::lev_distance::find_best_match_for_name;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticId};
 use rustc_hir as hir;
@@ -32,8 +34,6 @@ use rustc_span::symbol::sym;
 use rustc_span::{MultiSpan, Span, DUMMY_SP};
 use rustc_target::spec::abi;
 use smallvec::SmallVec;
-use syntax::ast;
-use syntax::util::lev_distance::find_best_match_for_name;
 
 use std::collections::BTreeSet;
 use std::iter;
diff --git a/src/librustc_typeck/check/autoderef.rs b/src/librustc_typeck/check/autoderef.rs
index 00e91decf78..67bfb090253 100644
--- a/src/librustc_typeck/check/autoderef.rs
+++ b/src/librustc_typeck/check/autoderef.rs
@@ -10,8 +10,8 @@ use rustc_hir as hir;
 use rustc_infer::infer::{InferCtxt, InferOk};
 use rustc_infer::traits::{self, TraitEngine};
 
+use rustc_ast::ast::Ident;
 use rustc_span::Span;
-use syntax::ast::Ident;
 
 use std::iter;
 
diff --git a/src/librustc_typeck/check/callee.rs b/src/librustc_typeck/check/callee.rs
index d0d07334fa5..3f8019e64b2 100644
--- a/src/librustc_typeck/check/callee.rs
+++ b/src/librustc_typeck/check/callee.rs
@@ -6,6 +6,7 @@ use crate::type_error_struct;
 use rustc::ty::adjustment::{Adjust, Adjustment, AllowTwoPhase, AutoBorrow, AutoBorrowMutability};
 use rustc::ty::subst::SubstsRef;
 use rustc::ty::{self, Ty, TyCtxt, TypeFoldable};
+use rustc_ast::ast::Ident;
 use rustc_errors::{struct_span_err, Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
 use rustc_hir::def::Res;
@@ -14,7 +15,6 @@ use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKi
 use rustc_infer::{infer, traits};
 use rustc_span::Span;
 use rustc_target::spec::abi;
-use syntax::ast::Ident;
 
 /// Checks that it is legal to call methods of the trait corresponding
 /// to `trait_id` (this only cares about the trait, not the specific
diff --git a/src/librustc_typeck/check/cast.rs b/src/librustc_typeck/check/cast.rs
index a67ceb856ce..ff100c261f1 100644
--- a/src/librustc_typeck/check/cast.rs
+++ b/src/librustc_typeck/check/cast.rs
@@ -41,12 +41,12 @@ use rustc::ty::cast::{CastKind, CastTy};
 use rustc::ty::error::TypeError;
 use rustc::ty::subst::SubstsRef;
 use rustc::ty::{self, Ty, TypeAndMut, TypeFoldable};
+use rustc_ast::ast;
 use rustc_errors::{struct_span_err, Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
 use rustc_infer::traits;
 use rustc_infer::traits::error_reporting::report_object_safety_error;
 use rustc_span::Span;
-use syntax::ast;
 
 /// Reifies a cast check to be checked once we have full type information for
 /// a function context.
diff --git a/src/librustc_typeck/check/demand.rs b/src/librustc_typeck/check/demand.rs
index 761e2fa8eac..0c5f3d3e99d 100644
--- a/src/librustc_typeck/check/demand.rs
+++ b/src/librustc_typeck/check/demand.rs
@@ -4,12 +4,12 @@ use rustc_infer::traits::{self, ObligationCause};
 
 use rustc::ty::adjustment::AllowTwoPhase;
 use rustc::ty::{self, AssocItem, Ty};
+use rustc_ast::util::parser::PREC_POSTFIX;
 use rustc_errors::{Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
 use rustc_hir::{is_range_literal, print, Node};
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::util::parser::PREC_POSTFIX;
 
 use super::method::probe;
 
diff --git a/src/librustc_typeck/check/expr.rs b/src/librustc_typeck/check/expr.rs
index 38d73256469..124d0f4b731 100644
--- a/src/librustc_typeck/check/expr.rs
+++ b/src/librustc_typeck/check/expr.rs
@@ -23,6 +23,8 @@ use rustc::ty::adjustment::{Adjust, Adjustment, AllowTwoPhase, AutoBorrow, AutoB
 use rustc::ty::Ty;
 use rustc::ty::TypeFoldable;
 use rustc::ty::{AdtKind, Visibility};
+use rustc_ast::ast;
+use rustc_ast::util::lev_distance::find_best_match_for_name;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticBuilder, DiagnosticId};
 use rustc_hir as hir;
@@ -35,8 +37,6 @@ use rustc_infer::traits::{self, ObligationCauseCode};
 use rustc_span::hygiene::DesugaringKind;
 use rustc_span::source_map::Span;
 use rustc_span::symbol::{kw, sym, Symbol};
-use syntax::ast;
-use syntax::util::lev_distance::find_best_match_for_name;
 
 use std::fmt::Display;
 
diff --git a/src/librustc_typeck/check/method/mod.rs b/src/librustc_typeck/check/method/mod.rs
index b09522bbd33..9b8d88e94b6 100644
--- a/src/librustc_typeck/check/method/mod.rs
+++ b/src/librustc_typeck/check/method/mod.rs
@@ -15,6 +15,7 @@ use rustc::ty::subst::Subst;
 use rustc::ty::subst::{InternalSubsts, SubstsRef};
 use rustc::ty::GenericParamDefKind;
 use rustc::ty::{self, ToPolyTraitRef, ToPredicate, Ty, TypeFoldable, WithConstness};
+use rustc_ast::ast;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::{Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
@@ -23,7 +24,6 @@ use rustc_hir::def_id::DefId;
 use rustc_infer::infer::{self, InferOk};
 use rustc_infer::traits;
 use rustc_span::Span;
-use syntax::ast;
 
 use self::probe::{IsSuggestion, ProbeScope};
 
diff --git a/src/librustc_typeck/check/method/probe.rs b/src/librustc_typeck/check/method/probe.rs
index 3e2826907b8..a52cabd8894 100644
--- a/src/librustc_typeck/check/method/probe.rs
+++ b/src/librustc_typeck/check/method/probe.rs
@@ -16,6 +16,8 @@ use rustc::ty::GenericParamDefKind;
 use rustc::ty::{
     self, ParamEnvAnd, ToPolyTraitRef, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness,
 };
+use rustc_ast::ast;
+use rustc_ast::util::lev_distance::{find_best_match_for_name, lev_distance};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::struct_span_err;
@@ -35,8 +37,6 @@ use std::cmp::max;
 use std::iter;
 use std::mem;
 use std::ops::Deref;
-use syntax::ast;
-use syntax::util::lev_distance::{find_best_match_for_name, lev_distance};
 
 use smallvec::{smallvec, SmallVec};
 
diff --git a/src/librustc_typeck/check/method/suggest.rs b/src/librustc_typeck/check/method/suggest.rs
index 44f87319ebf..33fecb81b60 100644
--- a/src/librustc_typeck/check/method/suggest.rs
+++ b/src/librustc_typeck/check/method/suggest.rs
@@ -7,6 +7,8 @@ use rustc::hir::map as hir_map;
 use rustc::hir::map::Map;
 use rustc::ty::print::with_crate_prefix;
 use rustc::ty::{self, ToPolyTraitRef, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness};
+use rustc_ast::ast;
+use rustc_ast::util::lev_distance;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
@@ -18,8 +20,6 @@ use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKi
 use rustc_infer::traits::Obligation;
 use rustc_span::symbol::kw;
 use rustc_span::{source_map, FileName, Span};
-use syntax::ast;
-use syntax::util::lev_distance;
 
 use std::cmp::Ordering;
 
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index ce2af9b96e5..317574ed963 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -106,6 +106,8 @@ use rustc::ty::{
     self, AdtKind, CanonicalUserType, Const, GenericParamDefKind, RegionKind, ToPolyTraitRef,
     ToPredicate, Ty, TyCtxt, UserType, WithConstness,
 };
+use rustc_ast::ast;
+use rustc_ast::util::parser::ExprPrecedence;
 use rustc_attr as attr;
 use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
@@ -130,8 +132,6 @@ use rustc_span::source_map::{original_sp, DUMMY_SP};
 use rustc_span::symbol::{kw, sym, Ident};
 use rustc_span::{self, BytePos, MultiSpan, Span};
 use rustc_target::spec::abi::Abi;
-use syntax::ast;
-use syntax::util::parser::ExprPrecedence;
 
 use std::cell::{Cell, Ref, RefCell, RefMut};
 use std::cmp;
diff --git a/src/librustc_typeck/check/op.rs b/src/librustc_typeck/check/op.rs
index b2db02d53c4..bf3511a2614 100644
--- a/src/librustc_typeck/check/op.rs
+++ b/src/librustc_typeck/check/op.rs
@@ -5,11 +5,11 @@ use super::{FnCtxt, Needs};
 use rustc::ty::adjustment::{Adjust, Adjustment, AllowTwoPhase, AutoBorrow, AutoBorrowMutability};
 use rustc::ty::TyKind::{Adt, Array, Char, FnDef, Never, Ref, Str, Tuple, Uint};
 use rustc::ty::{self, Ty, TypeFoldable};
+use rustc_ast::ast::Ident;
 use rustc_errors::{self, struct_span_err, Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use rustc_span::Span;
-use syntax::ast::Ident;
 
 impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     /// Checks a `a <op>= b`
diff --git a/src/librustc_typeck/check/pat.rs b/src/librustc_typeck/check/pat.rs
index d5cc19f986f..b7aac707a98 100644
--- a/src/librustc_typeck/check/pat.rs
+++ b/src/librustc_typeck/check/pat.rs
@@ -1,6 +1,8 @@
 use crate::check::FnCtxt;
 use rustc::ty::subst::GenericArg;
 use rustc::ty::{self, BindingMode, Ty, TypeFoldable};
+use rustc_ast::ast;
+use rustc_ast::util::lev_distance::find_best_match_for_name;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
@@ -12,8 +14,6 @@ use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKi
 use rustc_infer::traits::{ObligationCause, Pattern};
 use rustc_span::hygiene::DesugaringKind;
 use rustc_span::source_map::{Span, Spanned};
-use syntax::ast;
-use syntax::util::lev_distance::find_best_match_for_name;
 
 use std::cmp;
 use std::collections::hash_map::Entry::{Occupied, Vacant};
diff --git a/src/librustc_typeck/check/upvar.rs b/src/librustc_typeck/check/upvar.rs
index f42611c6340..b5ed6335dc0 100644
--- a/src/librustc_typeck/check/upvar.rs
+++ b/src/librustc_typeck/check/upvar.rs
@@ -37,6 +37,7 @@ use crate::mem_categorization as mc;
 use crate::mem_categorization::PlaceBase;
 use rustc::hir::map::Map;
 use rustc::ty::{self, Ty, TyCtxt, UpvarSubsts};
+use rustc_ast::ast;
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
@@ -44,7 +45,6 @@ use rustc_hir::def_id::LocalDefId;
 use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
 use rustc_infer::infer::UpvarRegion;
 use rustc_span::Span;
-use syntax::ast;
 
 impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub fn closure_analyze(&self, body: &'tcx hir::Body<'tcx>) {
diff --git a/src/librustc_typeck/check/wfcheck.rs b/src/librustc_typeck/check/wfcheck.rs
index c13e1e5b668..e8e34a4e8f0 100644
--- a/src/librustc_typeck/check/wfcheck.rs
+++ b/src/librustc_typeck/check/wfcheck.rs
@@ -7,6 +7,7 @@ use rustc::ty::subst::{InternalSubsts, Subst};
 use rustc::ty::{
     self, AdtKind, GenericParamDefKind, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness,
 };
+use rustc_ast::ast;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::{struct_span_err, Applicability, DiagnosticBuilder};
 use rustc_hir::def_id::DefId;
@@ -15,7 +16,6 @@ use rustc_infer::infer::opaque_types::may_define_opaque_type;
 use rustc_infer::traits::{self, ObligationCause, ObligationCauseCode};
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::ast;
 
 use rustc_hir as hir;
 use rustc_hir::itemlikevisit::ParItemLikeVisitor;
diff --git a/src/librustc_typeck/check_unused.rs b/src/librustc_typeck/check_unused.rs
index dd833d9751c..3517e09133c 100644
--- a/src/librustc_typeck/check_unused.rs
+++ b/src/librustc_typeck/check_unused.rs
@@ -1,5 +1,6 @@
 use crate::lint;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::Applicability;
 use rustc_hir as hir;
@@ -7,7 +8,6 @@ use rustc_hir::def_id::{DefId, DefIdSet, LOCAL_CRATE};
 use rustc_hir::itemlikevisit::ItemLikeVisitor;
 use rustc_hir::print::visibility_qualified;
 use rustc_span::Span;
-use syntax::ast;
 
 pub fn check_crate(tcx: TyCtxt<'_>) {
     let mut used_trait_imports = DefIdSet::default();
diff --git a/src/librustc_typeck/coherence/inherent_impls.rs b/src/librustc_typeck/coherence/inherent_impls.rs
index 49fa45836e1..60e5df68b58 100644
--- a/src/librustc_typeck/coherence/inherent_impls.rs
+++ b/src/librustc_typeck/coherence/inherent_impls.rs
@@ -13,8 +13,8 @@ use rustc_hir as hir;
 use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
 use rustc_hir::itemlikevisit::ItemLikeVisitor;
 
+use rustc_ast::ast;
 use rustc_span::Span;
-use syntax::ast;
 
 /// On-demand query: yields a map containing all types mapped to their inherent impls.
 pub fn crate_inherent_impls(tcx: TyCtxt<'_>, crate_num: CrateNum) -> &CrateInherentImpls {
diff --git a/src/librustc_typeck/collect.rs b/src/librustc_typeck/collect.rs
index 252abaee747..74111f8864e 100644
--- a/src/librustc_typeck/collect.rs
+++ b/src/librustc_typeck/collect.rs
@@ -31,6 +31,8 @@ use rustc::ty::util::Discr;
 use rustc::ty::util::IntTypeExt;
 use rustc::ty::{self, AdtKind, Const, ToPolyTraitRef, Ty, TyCtxt};
 use rustc::ty::{ReprOptions, ToPredicate, WithConstness};
+use rustc_ast::ast;
+use rustc_ast::ast::{Ident, MetaItemKind};
 use rustc_attr::{list_contains_name, mark_used, InlineAttr, OptimizeAttr};
 use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
@@ -43,8 +45,6 @@ use rustc_hir::{GenericParamKind, Node, Unsafety};
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::{Span, DUMMY_SP};
 use rustc_target::spec::abi;
-use syntax::ast;
-use syntax::ast::{Ident, MetaItemKind};
 
 mod type_of;
 
@@ -2554,7 +2554,7 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, id: DefId) -> CodegenFnAttrs {
 }
 
 fn check_link_ordinal(tcx: TyCtxt<'_>, attr: &ast::Attribute) -> Option<usize> {
-    use syntax::ast::{Lit, LitIntType, LitKind};
+    use rustc_ast::ast::{Lit, LitIntType, LitKind};
     let meta_item_list = attr.meta_item_list();
     let meta_item_list: Option<&[ast::NestedMetaItem]> = meta_item_list.as_ref().map(Vec::as_ref);
     let sole_meta_list = match meta_item_list {
diff --git a/src/librustdoc/clean/cfg.rs b/src/librustdoc/clean/cfg.rs
index da3a277dc2a..775d600fc3d 100644
--- a/src/librustdoc/clean/cfg.rs
+++ b/src/librustdoc/clean/cfg.rs
@@ -7,10 +7,10 @@ use std::fmt::{self, Write};
 use std::mem;
 use std::ops;
 
+use rustc_ast::ast::{LitKind, MetaItem, MetaItemKind, NestedMetaItem};
 use rustc_feature::Features;
 use rustc_session::parse::ParseSess;
 use rustc_span::symbol::{sym, Symbol};
-use syntax::ast::{LitKind, MetaItem, MetaItemKind, NestedMetaItem};
 
 use rustc_span::Span;
 
diff --git a/src/librustdoc/clean/cfg/tests.rs b/src/librustdoc/clean/cfg/tests.rs
index d090bf32503..3b26742e716 100644
--- a/src/librustdoc/clean/cfg/tests.rs
+++ b/src/librustdoc/clean/cfg/tests.rs
@@ -1,10 +1,10 @@
 use super::*;
 
+use rustc_ast::ast::*;
+use rustc_ast::attr;
+use rustc_ast::with_default_globals;
 use rustc_span::symbol::Symbol;
 use rustc_span::DUMMY_SP;
-use syntax::ast::*;
-use syntax::attr;
-use syntax::with_default_globals;
 
 fn word_cfg(s: &str) -> Cfg {
     Cfg::Cfg(Symbol::intern(s), None)
diff --git a/src/librustdoc/clean/inline.rs b/src/librustdoc/clean/inline.rs
index 78222d21b93..618dfa0d33a 100644
--- a/src/librustdoc/clean/inline.rs
+++ b/src/librustdoc/clean/inline.rs
@@ -3,6 +3,7 @@
 use std::iter::once;
 
 use rustc::ty;
+use rustc_ast::ast;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind, Res};
@@ -13,7 +14,6 @@ use rustc_mir::const_eval::is_min_const_fn;
 use rustc_span::hygiene::MacroKind;
 use rustc_span::symbol::sym;
 use rustc_span::Span;
-use syntax::ast;
 
 use crate::clean::{self, GetDefId, ToSource, TypeKind};
 use crate::core::DocContext;
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index 8be6bf8f0d3..0b26a17e2d5 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -15,6 +15,7 @@ use rustc::middle::stability;
 use rustc::ty::fold::TypeFolder;
 use rustc::ty::subst::InternalSubsts;
 use rustc::ty::{self, AdtKind, Lift, Ty, TyCtxt};
+use rustc_ast::ast::{self, Ident};
 use rustc_attr as attr;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
@@ -27,7 +28,6 @@ use rustc_span::hygiene::MacroKind;
 use rustc_span::symbol::{kw, sym};
 use rustc_span::{self, Pos};
 use rustc_typeck::hir_ty_to_ty;
-use syntax::ast::{self, Ident};
 
 use std::collections::hash_map::Entry;
 use std::default::Default;
diff --git a/src/librustdoc/clean/types.rs b/src/librustdoc/clean/types.rs
index ee685c90a62..9c3bedfe37c 100644
--- a/src/librustdoc/clean/types.rs
+++ b/src/librustdoc/clean/types.rs
@@ -11,6 +11,9 @@ use std::{slice, vec};
 use rustc::middle::lang_items;
 use rustc::middle::stability;
 use rustc::ty::layout::VariantIdx;
+use rustc_ast::ast::{self, AttrStyle, Ident};
+use rustc_ast::attr;
+use rustc_ast::util::comments::strip_doc_comment_decoration;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 use rustc_hir::def::Res;
@@ -22,9 +25,6 @@ use rustc_span::source_map::DUMMY_SP;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{self, FileName};
 use rustc_target::spec::abi::Abi;
-use syntax::ast::{self, AttrStyle, Ident};
-use syntax::attr;
-use syntax::util::comments::strip_doc_comment_decoration;
 
 use crate::clean::cfg::Cfg;
 use crate::clean::external_path;
@@ -421,7 +421,7 @@ pub struct Attributes {
 impl Attributes {
     /// Extracts the content from an attribute `#[doc(cfg(content))]`.
     pub fn extract_cfg(mi: &ast::MetaItem) -> Option<&ast::MetaItem> {
-        use syntax::ast::NestedMetaItem::MetaItem;
+        use rustc_ast::ast::NestedMetaItem::MetaItem;
 
         if let ast::MetaItemKind::List(ref nmis) = mi.kind {
             if nmis.len() == 1 {
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index 43d3ad21829..8bc34e949f1 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -14,13 +14,13 @@ use rustc_interface::interface;
 use rustc_resolve as resolve;
 use rustc_session::lint;
 
+use rustc_ast::ast::CRATE_NODE_ID;
 use rustc_attr as attr;
 use rustc_errors::emitter::{Emitter, EmitterWriter};
 use rustc_errors::json::JsonEmitter;
 use rustc_span::source_map;
 use rustc_span::symbol::sym;
 use rustc_span::DUMMY_SP;
-use syntax::ast::CRATE_NODE_ID;
 
 use rustc_data_structures::sync::{self, Lrc};
 use std::cell::RefCell;
diff --git a/src/librustdoc/doctree.rs b/src/librustdoc/doctree.rs
index 744201a0050..becdeaba50f 100644
--- a/src/librustdoc/doctree.rs
+++ b/src/librustdoc/doctree.rs
@@ -2,10 +2,10 @@
 //! manner (and with prettier names) before cleaning.
 pub use self::StructType::*;
 
+use rustc_ast::ast;
+use rustc_ast::ast::Name;
 use rustc_span::hygiene::MacroKind;
 use rustc_span::{self, Span};
-use syntax::ast;
-use syntax::ast::Name;
 
 use rustc_hir as hir;
 use rustc_hir::def_id::CrateNum;
diff --git a/src/librustdoc/html/highlight.rs b/src/librustdoc/html/highlight.rs
index 9ab94e47c83..0b4bb304fe9 100644
--- a/src/librustdoc/html/highlight.rs
+++ b/src/librustdoc/html/highlight.rs
@@ -11,12 +11,12 @@ use std::fmt::Display;
 use std::io;
 use std::io::prelude::*;
 
+use rustc_ast::token::{self, Token};
 use rustc_parse::lexer;
 use rustc_session::parse::ParseSess;
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::{kw, sym};
 use rustc_span::{FileName, Span};
-use syntax::token::{self, Token};
 
 /// Highlights `src`, returning the HTML output.
 pub fn render_with_highlighting(
diff --git a/src/librustdoc/html/render.rs b/src/librustdoc/html/render.rs
index 54d5a2efc8a..4aa3fa39fb4 100644
--- a/src/librustdoc/html/render.rs
+++ b/src/librustdoc/html/render.rs
@@ -44,6 +44,7 @@ use std::sync::Arc;
 
 use rustc::middle::privacy::AccessLevels;
 use rustc::middle::stability;
+use rustc_ast::ast;
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::flock;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
@@ -57,7 +58,6 @@ use rustc_span::source_map::FileName;
 use rustc_span::symbol::{sym, Symbol};
 use serde::ser::SerializeSeq;
 use serde::{Serialize, Serializer};
-use syntax::ast;
 
 use crate::clean::{self, AttributesExt, Deprecation, GetDefId, SelfTy};
 use crate::config::RenderOptions;
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index 8af77fdf75e..4ea14ab9077 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -17,7 +17,7 @@
 extern crate env_logger;
 extern crate getopts;
 extern crate rustc;
-extern crate rustc_ast as syntax;
+extern crate rustc_ast;
 extern crate rustc_ast_pretty;
 extern crate rustc_attr;
 extern crate rustc_data_structures;
diff --git a/src/librustdoc/passes/calculate_doc_coverage.rs b/src/librustdoc/passes/calculate_doc_coverage.rs
index 7ed531c9206..d4a7f3313a4 100644
--- a/src/librustdoc/passes/calculate_doc_coverage.rs
+++ b/src/librustdoc/passes/calculate_doc_coverage.rs
@@ -3,9 +3,9 @@ use crate::core::DocContext;
 use crate::fold::{self, DocFolder};
 use crate::passes::Pass;
 
+use rustc_ast::attr;
 use rustc_span::symbol::sym;
 use rustc_span::FileName;
-use syntax::attr;
 
 use std::collections::BTreeMap;
 use std::ops;
diff --git a/src/librustdoc/passes/check_code_block_syntax.rs b/src/librustdoc/passes/check_code_block_syntax.rs
index a6dad3c3920..3e0ff0b3d9a 100644
--- a/src/librustdoc/passes/check_code_block_syntax.rs
+++ b/src/librustdoc/passes/check_code_block_syntax.rs
@@ -1,10 +1,10 @@
+use rustc_ast::token;
 use rustc_data_structures::sync::{Lock, Lrc};
 use rustc_errors::{emitter::Emitter, Applicability, Diagnostic, Handler};
 use rustc_parse::lexer::StringReader as Lexer;
 use rustc_session::parse::ParseSess;
 use rustc_span::source_map::{FilePathMapping, SourceMap};
 use rustc_span::{FileName, InnerSpan};
-use syntax::token;
 
 use crate::clean;
 use crate::core::DocContext;
diff --git a/src/librustdoc/passes/collect_intra_doc_links.rs b/src/librustdoc/passes/collect_intra_doc_links.rs
index 0b27e5cf806..ad121a667da 100644
--- a/src/librustdoc/passes/collect_intra_doc_links.rs
+++ b/src/librustdoc/passes/collect_intra_doc_links.rs
@@ -1,5 +1,6 @@
 use rustc::lint;
 use rustc::ty;
+use rustc_ast::ast::{self, Ident};
 use rustc_errors::Applicability;
 use rustc_expand::base::SyntaxExtensionKind;
 use rustc_feature::UnstableFeatures;
@@ -13,7 +14,6 @@ use rustc_hir::def_id::DefId;
 use rustc_resolve::ParentScope;
 use rustc_span::symbol::Symbol;
 use rustc_span::DUMMY_SP;
-use syntax::ast::{self, Ident};
 
 use std::ops::Range;
 
@@ -60,7 +60,7 @@ impl<'a, 'tcx> LinkCollector<'a, 'tcx> {
         &self,
         path_str: &str,
         current_item: &Option<String>,
-        module_id: syntax::ast::NodeId,
+        module_id: rustc_ast::ast::NodeId,
     ) -> Result<(Res, Option<String>), ErrorKind> {
         let cx = self.cx;
 
@@ -896,20 +896,20 @@ fn handle_variant(
 }
 
 const PRIMITIVES: &[(&str, Res)] = &[
-    ("u8", Res::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::U8))),
-    ("u16", Res::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::U16))),
-    ("u32", Res::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::U32))),
-    ("u64", Res::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::U64))),
-    ("u128", Res::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::U128))),
-    ("usize", Res::PrimTy(hir::PrimTy::Uint(syntax::ast::UintTy::Usize))),
-    ("i8", Res::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::I8))),
-    ("i16", Res::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::I16))),
-    ("i32", Res::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::I32))),
-    ("i64", Res::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::I64))),
-    ("i128", Res::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::I128))),
-    ("isize", Res::PrimTy(hir::PrimTy::Int(syntax::ast::IntTy::Isize))),
-    ("f32", Res::PrimTy(hir::PrimTy::Float(syntax::ast::FloatTy::F32))),
-    ("f64", Res::PrimTy(hir::PrimTy::Float(syntax::ast::FloatTy::F64))),
+    ("u8", Res::PrimTy(hir::PrimTy::Uint(rustc_ast::ast::UintTy::U8))),
+    ("u16", Res::PrimTy(hir::PrimTy::Uint(rustc_ast::ast::UintTy::U16))),
+    ("u32", Res::PrimTy(hir::PrimTy::Uint(rustc_ast::ast::UintTy::U32))),
+    ("u64", Res::PrimTy(hir::PrimTy::Uint(rustc_ast::ast::UintTy::U64))),
+    ("u128", Res::PrimTy(hir::PrimTy::Uint(rustc_ast::ast::UintTy::U128))),
+    ("usize", Res::PrimTy(hir::PrimTy::Uint(rustc_ast::ast::UintTy::Usize))),
+    ("i8", Res::PrimTy(hir::PrimTy::Int(rustc_ast::ast::IntTy::I8))),
+    ("i16", Res::PrimTy(hir::PrimTy::Int(rustc_ast::ast::IntTy::I16))),
+    ("i32", Res::PrimTy(hir::PrimTy::Int(rustc_ast::ast::IntTy::I32))),
+    ("i64", Res::PrimTy(hir::PrimTy::Int(rustc_ast::ast::IntTy::I64))),
+    ("i128", Res::PrimTy(hir::PrimTy::Int(rustc_ast::ast::IntTy::I128))),
+    ("isize", Res::PrimTy(hir::PrimTy::Int(rustc_ast::ast::IntTy::Isize))),
+    ("f32", Res::PrimTy(hir::PrimTy::Float(rustc_ast::ast::FloatTy::F32))),
+    ("f64", Res::PrimTy(hir::PrimTy::Float(rustc_ast::ast::FloatTy::F64))),
     ("str", Res::PrimTy(hir::PrimTy::Str)),
     ("bool", Res::PrimTy(hir::PrimTy::Bool)),
     ("char", Res::PrimTy(hir::PrimTy::Char)),
diff --git a/src/librustdoc/test.rs b/src/librustdoc/test.rs
index f8e318efae4..b63dbbf80d8 100644
--- a/src/librustdoc/test.rs
+++ b/src/librustdoc/test.rs
@@ -1,6 +1,8 @@
 use rustc::hir::map::Map;
 use rustc::session::{self, config, DiagnosticOutput};
 use rustc::util::common::ErrorReported;
+use rustc_ast::ast;
+use rustc_ast::with_globals;
 use rustc_data_structures::sync::Lrc;
 use rustc_feature::UnstableFeatures;
 use rustc_hir as hir;
@@ -17,8 +19,6 @@ use std::panic;
 use std::path::PathBuf;
 use std::process::{self, Command, Stdio};
 use std::str;
-use syntax::ast;
-use syntax::with_globals;
 use tempfile::Builder as TempFileBuilder;
 
 use crate::clean::Attributes;
diff --git a/src/librustdoc/visit_ast.rs b/src/librustdoc/visit_ast.rs
index d3d45ccccad..8f2f88d08bf 100644
--- a/src/librustdoc/visit_ast.rs
+++ b/src/librustdoc/visit_ast.rs
@@ -3,6 +3,7 @@
 
 use rustc::middle::privacy::AccessLevel;
 use rustc::ty::TyCtxt;
+use rustc_ast::ast;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
@@ -12,7 +13,6 @@ use rustc_span::hygiene::MacroKind;
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{kw, sym};
 use rustc_span::{self, Span};
-use syntax::ast;
 
 use std::mem;
 
diff --git a/src/test/ui-fulldeps/auxiliary/issue-40001-plugin.rs b/src/test/ui-fulldeps/auxiliary/issue-40001-plugin.rs
index 91b3372e8f4..1b6a38acb1c 100644
--- a/src/test/ui-fulldeps/auxiliary/issue-40001-plugin.rs
+++ b/src/test/ui-fulldeps/auxiliary/issue-40001-plugin.rs
@@ -9,7 +9,7 @@ extern crate rustc_lint;
 #[macro_use]
 extern crate rustc_session;
 extern crate rustc_span;
-extern crate syntax;
+extern crate rustc_ast;
 
 use rustc_ast_pretty::pprust;
 use rustc_driver::plugin::Registry;
diff --git a/src/test/ui-fulldeps/auxiliary/lint-for-crate-rpass.rs b/src/test/ui-fulldeps/auxiliary/lint-for-crate-rpass.rs
index eb251a0a3ad..4936bdb1ece 100644
--- a/src/test/ui-fulldeps/auxiliary/lint-for-crate-rpass.rs
+++ b/src/test/ui-fulldeps/auxiliary/lint-for-crate-rpass.rs
@@ -9,12 +9,12 @@ extern crate rustc_span;
 extern crate rustc_lint;
 #[macro_use]
 extern crate rustc_session;
-extern crate syntax;
+extern crate rustc_ast;
 
 use rustc_driver::plugin::Registry;
 use rustc_lint::{LateContext, LateLintPass, LintContext, LintPass};
 use rustc_span::symbol::Symbol;
-use syntax::attr;
+use rustc_ast::attr;
 
 macro_rules! fake_lint_pass {
     ($struct:ident, $($attr:expr),*) => {
diff --git a/src/test/ui-fulldeps/auxiliary/lint-for-crate.rs b/src/test/ui-fulldeps/auxiliary/lint-for-crate.rs
index e5f4bf88d57..32b7ed9dfe2 100644
--- a/src/test/ui-fulldeps/auxiliary/lint-for-crate.rs
+++ b/src/test/ui-fulldeps/auxiliary/lint-for-crate.rs
@@ -10,12 +10,12 @@ extern crate rustc_lint;
 #[macro_use]
 extern crate rustc_session;
 extern crate rustc_span;
-extern crate syntax;
+extern crate rustc_ast;
 
 use rustc_driver::plugin::Registry;
 use rustc_lint::{LateContext, LateLintPass, LintArray, LintContext, LintPass};
 use rustc_span::symbol::Symbol;
-use syntax::attr;
+use rustc_ast::attr;
 
 declare_lint! {
     CRATE_NOT_OKAY,
diff --git a/src/test/ui-fulldeps/auxiliary/lint-plugin-test.rs b/src/test/ui-fulldeps/auxiliary/lint-plugin-test.rs
index ad5f882c434..bb2a4d03734 100644
--- a/src/test/ui-fulldeps/auxiliary/lint-plugin-test.rs
+++ b/src/test/ui-fulldeps/auxiliary/lint-plugin-test.rs
@@ -3,7 +3,7 @@
 #![feature(plugin_registrar)]
 #![feature(box_syntax, rustc_private)]
 
-extern crate syntax;
+extern crate rustc_ast;
 
 // Load rustc as a plugin to get macros
 extern crate rustc_driver;
@@ -14,7 +14,7 @@ extern crate rustc_session;
 
 use rustc_driver::plugin::Registry;
 use rustc_lint::{EarlyContext, EarlyLintPass, LintArray, LintContext, LintPass};
-use syntax::ast;
+use rustc_ast::ast;
 declare_lint!(TEST_LINT, Warn, "Warn about items named 'lintme'");
 
 declare_lint_pass!(Pass => [TEST_LINT]);
diff --git a/src/test/ui-fulldeps/auxiliary/lint-tool-test.rs b/src/test/ui-fulldeps/auxiliary/lint-tool-test.rs
index b14dbdf8f93..8c517e2bb5d 100644
--- a/src/test/ui-fulldeps/auxiliary/lint-tool-test.rs
+++ b/src/test/ui-fulldeps/auxiliary/lint-tool-test.rs
@@ -1,7 +1,7 @@
 #![feature(plugin_registrar)]
 #![feature(box_syntax, rustc_private)]
 
-extern crate syntax;
+extern crate rustc_ast;
 
 // Load rustc as a plugin to get macros
 extern crate rustc_driver;
@@ -12,7 +12,7 @@ extern crate rustc_session;
 
 use rustc_driver::plugin::Registry;
 use rustc_lint::{EarlyContext, EarlyLintPass, LintArray, LintContext, LintId, LintPass};
-use syntax::ast;
+use rustc_ast::ast;
 declare_tool_lint!(pub clippy::TEST_LINT, Warn, "Warn about stuff");
 declare_tool_lint!(
     /// Some docs
diff --git a/src/test/ui-fulldeps/auxiliary/macro-crate-test.rs b/src/test/ui-fulldeps/auxiliary/macro-crate-test.rs
index fa136fd54c2..56a560acbb4 100644
--- a/src/test/ui-fulldeps/auxiliary/macro-crate-test.rs
+++ b/src/test/ui-fulldeps/auxiliary/macro-crate-test.rs
@@ -4,7 +4,7 @@
 #![crate_type = "proc-macro"]
 #![feature(rustc_private)]
 
-extern crate syntax;
+extern crate rustc_ast;
 extern crate rustc;
 extern crate rustc_driver;
 extern crate proc_macro;
diff --git a/src/test/ui-fulldeps/mod_dir_path_canonicalized.rs b/src/test/ui-fulldeps/mod_dir_path_canonicalized.rs
index 4a0e7135c7c..1046355a343 100644
--- a/src/test/ui-fulldeps/mod_dir_path_canonicalized.rs
+++ b/src/test/ui-fulldeps/mod_dir_path_canonicalized.rs
@@ -4,7 +4,7 @@
 
 #![feature(rustc_private)]
 
-extern crate syntax;
+extern crate rustc_ast;
 extern crate rustc_parse;
 extern crate rustc_session;
 extern crate rustc_span;
@@ -18,7 +18,7 @@ use std::path::Path;
 mod gravy;
 
 pub fn main() {
-    syntax::with_default_globals(|| parse());
+    rustc_ast::with_default_globals(|| parse());
 
     assert_eq!(gravy::foo(), 10);
 }
diff --git a/src/test/ui-fulldeps/pprust-expr-roundtrip.rs b/src/test/ui-fulldeps/pprust-expr-roundtrip.rs
index 38576ef39d1..365ae301c0f 100644
--- a/src/test/ui-fulldeps/pprust-expr-roundtrip.rs
+++ b/src/test/ui-fulldeps/pprust-expr-roundtrip.rs
@@ -21,7 +21,7 @@
 
 extern crate rustc_ast_pretty;
 extern crate rustc_data_structures;
-extern crate syntax;
+extern crate rustc_ast;
 extern crate rustc_parse;
 extern crate rustc_session;
 extern crate rustc_span;
@@ -32,9 +32,9 @@ use rustc_parse::new_parser_from_source_str;
 use rustc_session::parse::ParseSess;
 use rustc_span::source_map::{Spanned, DUMMY_SP, FileName};
 use rustc_span::source_map::FilePathMapping;
-use syntax::ast::*;
-use syntax::mut_visit::{self, MutVisitor, visit_clobber};
-use syntax::ptr::P;
+use rustc_ast::ast::*;
+use rustc_ast::mut_visit::{self, MutVisitor, visit_clobber};
+use rustc_ast::ptr::P;
 
 fn parse_expr(ps: &ParseSess, src: &str) -> Option<P<Expr>> {
     let src_as_string = src.to_string();
@@ -205,7 +205,7 @@ impl MutVisitor for AddParens {
 }
 
 fn main() {
-    syntax::with_default_globals(|| run());
+    rustc_ast::with_default_globals(|| run());
 }
 
 fn run() {
diff --git a/src/test/ui/regions/regions-trait-object-1.rs b/src/test/ui/regions/regions-trait-object-1.rs
index b8a3ad4548f..e2520d97890 100644
--- a/src/test/ui/regions/regions-trait-object-1.rs
+++ b/src/test/ui/regions/regions-trait-object-1.rs
@@ -1,7 +1,7 @@
 // run-pass
 // This is a regression test for something that only came up while
 // attempting to bootstrap librustc_ast; it is adapted from
-// `syntax::ext::tt::generic_extension`.
+// `rustc_ast::ext::tt::generic_extension`.
 
 
 pub struct E<'a> {
diff --git a/src/test/ui/unboxed-closures/unboxed-closures-unique-type-id.rs b/src/test/ui/unboxed-closures/unboxed-closures-unique-type-id.rs
index 5d1e00d2d35..9c6be50c5c7 100644
--- a/src/test/ui/unboxed-closures/unboxed-closures-unique-type-id.rs
+++ b/src/test/ui/unboxed-closures/unboxed-closures-unique-type-id.rs
@@ -4,7 +4,7 @@
 //
 //    error: internal compiler error: get_unique_type_id_of_type() -
 //    unexpected type: closure,
-//    Closure(syntax::ast::DefId{krate: 0, node: 66},
+//    Closure(rustc_ast::ast::DefId{krate: 0, node: 66},
 //    ReScope(63))
 //
 // This is a regression test for issue #17021.
diff --git a/src/tools/error_index_generator/main.rs b/src/tools/error_index_generator/main.rs
index 313a303edb2..3335816f09f 100644
--- a/src/tools/error_index_generator/main.rs
+++ b/src/tools/error_index_generator/main.rs
@@ -2,8 +2,8 @@
 #![deny(warnings)]
 
 extern crate env_logger;
+extern crate rustc_ast;
 extern crate rustc_span;
-extern crate syntax;
 
 use std::cell::RefCell;
 use std::collections::BTreeMap;
@@ -285,7 +285,7 @@ fn parse_args() -> (OutputFormat, PathBuf) {
 fn main() {
     env_logger::init();
     let (format, dst) = parse_args();
-    let result = syntax::with_default_globals(move || main_with_result(format, &dst));
+    let result = rustc_ast::with_default_globals(move || main_with_result(format, &dst));
     if let Err(e) = result {
         panic!("{}", e.to_string());
     }