From: Vadim Petrochenkov <vadim.petrochenkov@gmail.com>
Date: Tue, 23 Jul 2019 15:50:47 +0000 (+0300)
Subject: cleanup: Remove `extern crate serialize as rustc_serialize`s
X-Git-Url: https://git.lizzy.rs/?a=commitdiff_plain;h=614037171bf0140390033cc60f5e99aac079a0e5;p=rust.git

cleanup: Remove `extern crate serialize as rustc_serialize`s
---

diff --git a/src/librustc/Cargo.toml b/src/librustc/Cargo.toml
index 1677ef4b607..0222a3dde7a 100644
--- a/src/librustc/Cargo.toml
+++ b/src/librustc/Cargo.toml
@@ -27,7 +27,7 @@ rustc_target = { path = "../librustc_target" }
 rustc_macros = { path = "../librustc_macros" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 errors = { path = "../librustc_errors", package = "rustc_errors" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
 backtrace = "0.3.3"
diff --git a/src/librustc/hir/def_id.rs b/src/librustc/hir/def_id.rs
index 057d878a0ab..f3edb5f8621 100644
--- a/src/librustc/hir/def_id.rs
+++ b/src/librustc/hir/def_id.rs
@@ -1,7 +1,6 @@
 use crate::ty::{self, TyCtxt};
 use crate::hir::map::definitions::FIRST_FREE_DEF_INDEX;
 use rustc_data_structures::indexed_vec::Idx;
-use serialize;
 use std::fmt;
 use std::u32;
 
@@ -93,8 +92,8 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
     }
 }
 
-impl serialize::UseSpecializedEncodable for CrateNum {}
-impl serialize::UseSpecializedDecodable for CrateNum {}
+impl rustc_serialize::UseSpecializedEncodable for CrateNum {}
+impl rustc_serialize::UseSpecializedDecodable for CrateNum {}
 
 newtype_index! {
     /// A DefIndex is an index into the hir-map for a crate, identifying a
@@ -134,8 +133,8 @@ pub fn to_proc_macro_index(self: DefIndex) -> usize {
     }
 }
 
-impl serialize::UseSpecializedEncodable for DefIndex {}
-impl serialize::UseSpecializedDecodable for DefIndex {}
+impl rustc_serialize::UseSpecializedEncodable for DefIndex {}
+impl rustc_serialize::UseSpecializedDecodable for DefIndex {}
 
 /// A `DefId` identifies a particular *definition*, by combining a crate
 /// index and a def index.
@@ -186,8 +185,8 @@ pub fn describe_as_module(&self, tcx: TyCtxt<'_>) -> String {
     }
 }
 
-impl serialize::UseSpecializedEncodable for DefId {}
-impl serialize::UseSpecializedDecodable for DefId {}
+impl rustc_serialize::UseSpecializedEncodable for DefId {}
+impl rustc_serialize::UseSpecializedDecodable for DefId {}
 
 /// A LocalDefId is equivalent to a DefId with `krate == LOCAL_CRATE`. Since
 /// we encode this information in the type, we can ensure at compile time that
@@ -220,5 +219,5 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
     }
 }
 
-impl serialize::UseSpecializedEncodable for LocalDefId {}
-impl serialize::UseSpecializedDecodable for LocalDefId {}
+impl rustc_serialize::UseSpecializedEncodable for LocalDefId {}
+impl rustc_serialize::UseSpecializedDecodable for LocalDefId {}
diff --git a/src/librustc/hir/mod.rs b/src/librustc/hir/mod.rs
index e7b37d40b4b..3708a905a4b 100644
--- a/src/librustc/hir/mod.rs
+++ b/src/librustc/hir/mod.rs
@@ -34,7 +34,7 @@
 use rustc_data_structures::thin_vec::ThinVec;
 use rustc_macros::HashStable;
 
-use serialize::{self, Encoder, Encodable, Decoder, Decodable};
+use rustc_serialize::{self, Encoder, Encodable, Decoder, Decodable};
 use std::collections::{BTreeSet, BTreeMap};
 use std::fmt;
 use smallvec::SmallVec;
@@ -92,7 +92,7 @@ pub fn owner_local_def_id(self) -> LocalDefId {
     }
 }
 
-impl serialize::UseSpecializedEncodable for HirId {
+impl rustc_serialize::UseSpecializedEncodable for HirId {
     fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
         let HirId {
             owner,
@@ -104,7 +104,7 @@ fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
     }
 }
 
-impl serialize::UseSpecializedDecodable for HirId {
+impl rustc_serialize::UseSpecializedDecodable for HirId {
     fn default_decode<D: Decoder>(d: &mut D) -> Result<HirId, D::Error> {
         let owner = DefIndex::decode(d)?;
         let local_id = ItemLocalId::decode(d)?;
diff --git a/src/librustc/hir/ptr.rs b/src/librustc/hir/ptr.rs
index 3a87b36a1b4..1976b4c9e54 100644
--- a/src/librustc/hir/ptr.rs
+++ b/src/librustc/hir/ptr.rs
@@ -7,7 +7,7 @@
 use std::ops::Deref;
 use std::{slice, vec};
 
-use serialize::{Encodable, Decodable, Encoder, Decoder};
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
 
 use rustc_data_structures::stable_hasher::{StableHasher, StableHasherResult,
                                            HashStable};
diff --git a/src/librustc/infer/canonical/mod.rs b/src/librustc/infer/canonical/mod.rs
index b508f91e01e..6840611d4be 100644
--- a/src/librustc/infer/canonical/mod.rs
+++ b/src/librustc/infer/canonical/mod.rs
@@ -27,7 +27,7 @@
 use crate::mir::interpret::ConstValue;
 use rustc_data_structures::indexed_vec::IndexVec;
 use rustc_macros::HashStable;
-use serialize::UseSpecializedDecodable;
+use rustc_serialize::UseSpecializedDecodable;
 use smallvec::SmallVec;
 use std::ops::Index;
 use syntax::source_map::Span;
diff --git a/src/librustc/lib.rs b/src/librustc/lib.rs
index 63e0107a4d8..c7d4fa3aec6 100644
--- a/src/librustc/lib.rs
+++ b/src/librustc/lib.rs
@@ -75,16 +75,8 @@
 extern crate libc;
 #[macro_use] extern crate rustc_macros;
 #[macro_use] extern crate rustc_data_structures;
-
 #[macro_use] extern crate log;
 #[macro_use] extern crate syntax;
-
-// FIXME: This import is used by deriving `RustcDecodable` and `RustcEncodable`. Removing this
-// results in a bunch of "failed to resolve" errors. Hopefully, the compiler moves to serde or
-// something, and we can get rid of this.
-#[allow(rust_2018_idioms)]
-extern crate serialize as rustc_serialize;
-
 #[macro_use] extern crate smallvec;
 
 // Use the test crate here so we depend on getopts through it. This allow tools to link to both
diff --git a/src/librustc/lint/context.rs b/src/librustc/lint/context.rs
index 2930f7690dd..859bc86d3a0 100644
--- a/src/librustc/lint/context.rs
+++ b/src/librustc/lint/context.rs
@@ -23,7 +23,7 @@
 use crate::lint::builtin::BuiltinLintDiagnostics;
 use crate::lint::levels::{LintLevelSets, LintLevelsBuilder};
 use crate::middle::privacy::AccessLevels;
-use crate::rustc_serialize::{Decoder, Decodable, Encoder, Encodable};
+use rustc_serialize::{Decoder, Decodable, Encoder, Encodable};
 use crate::session::{config, early_error, Session};
 use crate::ty::{self, print::Printer, subst::Kind, TyCtxt, Ty};
 use crate::ty::layout::{LayoutError, LayoutOf, TyLayout};
diff --git a/src/librustc/mir/cache.rs b/src/librustc/mir/cache.rs
index d2cabb7e10b..3d33e249536 100644
--- a/src/librustc/mir/cache.rs
+++ b/src/librustc/mir/cache.rs
@@ -1,27 +1,25 @@
 use rustc_data_structures::indexed_vec::IndexVec;
 use rustc_data_structures::sync::{RwLock, MappedReadGuard, ReadGuard};
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher,
-                                           StableHasherResult};
+use rustc_data_structures::stable_hasher::{HashStable, StableHasher, StableHasherResult};
+use rustc_serialize::{Encodable, Encoder, Decodable, Decoder};
 use crate::ich::StableHashingContext;
 use crate::mir::{Body, BasicBlock};
 
-use crate::rustc_serialize as serialize;
-
 #[derive(Clone, Debug)]
 pub struct Cache {
     predecessors: RwLock<Option<IndexVec<BasicBlock, Vec<BasicBlock>>>>
 }
 
 
-impl serialize::Encodable for Cache {
-    fn encode<S: serialize::Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
-        serialize::Encodable::encode(&(), s)
+impl rustc_serialize::Encodable for Cache {
+    fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+        Encodable::encode(&(), s)
     }
 }
 
-impl serialize::Decodable for Cache {
-    fn decode<D: serialize::Decoder>(d: &mut D) -> Result<Self, D::Error> {
-        serialize::Decodable::decode(d).map(|_v: ()| Self::new())
+impl rustc_serialize::Decodable for Cache {
+    fn decode<D: Decoder>(d: &mut D) -> Result<Self, D::Error> {
+        Decodable::decode(d).map(|_v: ()| Self::new())
     }
 }
 
diff --git a/src/librustc/mir/interpret/allocation.rs b/src/librustc/mir/interpret/allocation.rs
index c8bf250d02b..51b2d0272a5 100644
--- a/src/librustc/mir/interpret/allocation.rs
+++ b/src/librustc/mir/interpret/allocation.rs
@@ -113,7 +113,7 @@ pub fn undef(size: Size, align: Align) -> Self {
     }
 }
 
-impl<'tcx> ::serialize::UseSpecializedDecodable for &'tcx Allocation {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for &'tcx Allocation {}
 
 /// Byte accessors
 impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> {
diff --git a/src/librustc/mir/interpret/mod.rs b/src/librustc/mir/interpret/mod.rs
index 1b294250aa3..3e9933a2475 100644
--- a/src/librustc/mir/interpret/mod.rs
+++ b/src/librustc/mir/interpret/mod.rs
@@ -27,7 +27,7 @@ macro_rules! err {
 use crate::ty::{self, TyCtxt, Instance, subst::UnpackedKind};
 use crate::ty::layout::{self, Size};
 use std::io;
-use crate::rustc_serialize::{Encoder, Decodable, Encodable};
+use rustc_serialize::{Encoder, Decodable, Encodable};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::{Lock as Mutex, HashMapExt};
 use rustc_data_structures::tiny_list::TinyList;
@@ -51,8 +51,8 @@ pub struct GlobalId<'tcx> {
 #[derive(Copy, Clone, Eq, Hash, Ord, PartialEq, PartialOrd, Debug)]
 pub struct AllocId(pub u64);
 
-impl crate::rustc_serialize::UseSpecializedEncodable for AllocId {}
-impl crate::rustc_serialize::UseSpecializedDecodable for AllocId {}
+impl rustc_serialize::UseSpecializedEncodable for AllocId {}
+impl rustc_serialize::UseSpecializedDecodable for AllocId {}
 
 #[derive(RustcDecodable, RustcEncodable)]
 enum AllocDiscriminant {
diff --git a/src/librustc/mir/mod.rs b/src/librustc/mir/mod.rs
index d8b641fbe31..571fc56a54e 100644
--- a/src/librustc/mir/mod.rs
+++ b/src/librustc/mir/mod.rs
@@ -9,7 +9,6 @@
 use crate::hir::{self, InlineAsm as HirInlineAsm};
 use crate::mir::interpret::{ConstValue, InterpError, Scalar};
 use crate::mir::visit::MirVisitable;
-use crate::rustc_serialize as serialize;
 use crate::ty::adjustment::PointerCast;
 use crate::ty::fold::{TypeFoldable, TypeFolder, TypeVisitor};
 use crate::ty::layout::VariantIdx;
@@ -28,6 +27,7 @@
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::sync::MappedReadGuard;
 use rustc_macros::HashStable;
+use rustc_serialize::{Encodable, Decodable};
 use smallvec::SmallVec;
 use std::borrow::Cow;
 use std::fmt::{self, Debug, Display, Formatter, Write};
@@ -463,8 +463,8 @@ pub fn assert_crate_local(self) -> T {
     }
 }
 
-impl<T: serialize::Encodable> serialize::UseSpecializedEncodable for ClearCrossCrate<T> {}
-impl<T: serialize::Decodable> serialize::UseSpecializedDecodable for ClearCrossCrate<T> {}
+impl<T: Encodable> rustc_serialize::UseSpecializedEncodable for ClearCrossCrate<T> {}
+impl<T: Decodable> rustc_serialize::UseSpecializedDecodable for ClearCrossCrate<T> {}
 
 /// Grouped information about the source code origin of a MIR entity.
 /// Intended to be inspected by diagnostics and debuginfo.
diff --git a/src/librustc/ty/codec.rs b/src/librustc/ty/codec.rs
index 26e7cc9004d..e3c6eca02d5 100644
--- a/src/librustc/ty/codec.rs
+++ b/src/librustc/ty/codec.rs
@@ -10,7 +10,7 @@
 use crate::hir::def_id::{DefId, CrateNum};
 use crate::infer::canonical::{CanonicalVarInfo, CanonicalVarInfos};
 use rustc_data_structures::fx::FxHashMap;
-use crate::rustc_serialize::{Decodable, Decoder, Encoder, Encodable, opaque};
+use rustc_serialize::{Decodable, Decoder, Encoder, Encodable, opaque};
 use std::hash::Hash;
 use std::intrinsics;
 use crate::ty::{self, Ty, TyCtxt};
@@ -333,7 +333,7 @@ mod __ty_decoder_impl {
             use $crate::ty::codec::*;
             use $crate::ty::subst::SubstsRef;
             use $crate::hir::def_id::{CrateNum};
-            use crate::rustc_serialize::{Decoder, SpecializedDecoder};
+            use rustc_serialize::{Decoder, SpecializedDecoder};
             use std::borrow::Cow;
 
             impl<$($typaram ),*> Decoder for $DecoderName<$($typaram),*> {
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index 538afa6054f..44897c8e903 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -32,7 +32,7 @@
 use arena::SyncDroplessArena;
 use crate::session::DataTypeKind;
 
-use serialize::{self, Encodable, Encoder};
+use rustc_serialize::{self, Encodable, Encoder};
 use std::cell::RefCell;
 use std::cmp::{self, Ordering};
 use std::fmt;
@@ -588,8 +588,8 @@ fn hash_stable<W: StableHasherResult>(&self,
 
 pub type Ty<'tcx> = &'tcx TyS<'tcx>;
 
-impl<'tcx> serialize::UseSpecializedEncodable for Ty<'tcx> {}
-impl<'tcx> serialize::UseSpecializedDecodable for Ty<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedEncodable for Ty<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for Ty<'tcx> {}
 
 pub type CanonicalTy<'tcx> = Canonical<'tcx, Ty<'tcx>>;
 
@@ -708,7 +708,7 @@ fn into_iter(self) -> Self::IntoIter {
     }
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for &'tcx List<Ty<'tcx>> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for &'tcx List<Ty<'tcx>> {}
 
 impl<T> List<T> {
     #[inline(always)]
@@ -1009,8 +1009,8 @@ pub struct GenericPredicates<'tcx> {
     pub predicates: Vec<(Predicate<'tcx>, Span)>,
 }
 
-impl<'tcx> serialize::UseSpecializedEncodable for GenericPredicates<'tcx> {}
-impl<'tcx> serialize::UseSpecializedDecodable for GenericPredicates<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedEncodable for GenericPredicates<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for GenericPredicates<'tcx> {}
 
 impl<'tcx> GenericPredicates<'tcx> {
     pub fn instantiate(
@@ -1985,13 +1985,13 @@ fn hash<H: Hasher>(&self, s: &mut H) {
     }
 }
 
-impl<'tcx> serialize::UseSpecializedEncodable for &'tcx AdtDef {
+impl<'tcx> rustc_serialize::UseSpecializedEncodable for &'tcx AdtDef {
     fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
         self.did.encode(s)
     }
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for &'tcx AdtDef {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for &'tcx AdtDef {}
 
 
 impl<'a> HashStable<StableHashingContext<'a>> for AdtDef {
diff --git a/src/librustc/ty/query/on_disk_cache.rs b/src/librustc/ty/query/on_disk_cache.rs
index a25c1e34cf1..211a28fe931 100644
--- a/src/librustc/ty/query/on_disk_cache.rs
+++ b/src/librustc/ty/query/on_disk_cache.rs
@@ -5,7 +5,7 @@
 use crate::ich::{CachingSourceMapView, Fingerprint};
 use crate::mir::{self, interpret};
 use crate::mir::interpret::{AllocDecodingSession, AllocDecodingState};
-use crate::rustc_serialize::{Decodable, Decoder, Encodable, Encoder, opaque,
+use rustc_serialize::{Decodable, Decoder, Encodable, Encoder, opaque,
                       SpecializedDecoder, SpecializedEncoder,
                       UseSpecializedDecodable, UseSpecializedEncodable};
 use crate::session::{CrateDisambiguator, Session};
diff --git a/src/librustc/ty/sty.rs b/src/librustc/ty/sty.rs
index 5d17080a9b2..49a0fd827fb 100644
--- a/src/librustc/ty/sty.rs
+++ b/src/librustc/ty/sty.rs
@@ -26,7 +26,6 @@
 use syntax::ast::{self, Ident};
 use syntax::symbol::{kw, InternedString};
 
-use serialize;
 use self::InferTy::*;
 use self::TyKind::*;
 
@@ -640,7 +639,7 @@ pub fn with_self_ty(&self, tcx: TyCtxt<'tcx>, self_ty: Ty<'tcx>) -> ty::Predicat
     }
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for &'tcx List<ExistentialPredicate<'tcx>> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for &'tcx List<ExistentialPredicate<'tcx>> {}
 
 impl<'tcx> List<ExistentialPredicate<'tcx>> {
     /// Returns the "principal def id" of this set of existential predicates.
@@ -1324,7 +1323,7 @@ pub enum RegionKind {
     ReClosureBound(RegionVid),
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for Region<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for Region<'tcx> {}
 
 #[derive(Copy, Clone, PartialEq, Eq, Hash, RustcEncodable, RustcDecodable, Debug, PartialOrd, Ord)]
 pub struct EarlyBoundRegion {
@@ -2333,7 +2332,7 @@ pub fn unwrap_usize(&self, tcx: TyCtxt<'tcx>) -> u64 {
     }
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for &'tcx Const<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for &'tcx Const<'tcx> {}
 
 /// An inference variable for a const, for use in const generics.
 #[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd,
diff --git a/src/librustc/ty/subst.rs b/src/librustc/ty/subst.rs
index 79dcd327f52..ea829da783e 100644
--- a/src/librustc/ty/subst.rs
+++ b/src/librustc/ty/subst.rs
@@ -6,7 +6,7 @@
 use crate::ty::fold::{TypeFoldable, TypeFolder, TypeVisitor};
 use crate::mir::interpret::ConstValue;
 
-use serialize::{self, Encodable, Encoder, Decodable, Decoder};
+use rustc_serialize::{self, Encodable, Encoder, Decodable, Decoder};
 use syntax_pos::{Span, DUMMY_SP};
 use smallvec::SmallVec;
 use rustc_macros::HashStable;
@@ -399,7 +399,7 @@ fn super_visit_with<V: TypeVisitor<'tcx>>(&self, visitor: &mut V) -> bool {
     }
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for SubstsRef<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for SubstsRef<'tcx> {}
 
 ///////////////////////////////////////////////////////////////////////////
 // Public trait `Subst`
diff --git a/src/librustc_codegen_ssa/Cargo.toml b/src/librustc_codegen_ssa/Cargo.toml
index e7ee06df7e1..90d7320987c 100644
--- a/src/librustc_codegen_ssa/Cargo.toml
+++ b/src/librustc_codegen_ssa/Cargo.toml
@@ -20,7 +20,7 @@ jobserver = "0.1.11"
 parking_lot = "0.7"
 tempfile = "3.0.5"
 
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
 rustc = { path = "../librustc" }
diff --git a/src/librustc_codegen_ssa/back/linker.rs b/src/librustc_codegen_ssa/back/linker.rs
index 32696d46cd5..882963f9174 100644
--- a/src/librustc_codegen_ssa/back/linker.rs
+++ b/src/librustc_codegen_ssa/back/linker.rs
@@ -16,7 +16,7 @@
                              LinkerPluginLto, Lto};
 use rustc::ty::TyCtxt;
 use rustc_target::spec::{LinkerFlavor, LldFlavor};
-use serialize::{json, Encoder};
+use rustc_serialize::{json, Encoder};
 
 /// For all the linkers we support, and information they might
 /// need out of the shared crate context before we get rid of it.
diff --git a/src/librustc_codegen_ssa/back/wasm.rs b/src/librustc_codegen_ssa/back/wasm.rs
index f90bb89fbe8..2a9e81a788e 100644
--- a/src/librustc_codegen_ssa/back/wasm.rs
+++ b/src/librustc_codegen_ssa/back/wasm.rs
@@ -2,7 +2,7 @@
 use std::path::Path;
 use std::str;
 
-use serialize::leb128;
+use rustc_serialize::leb128;
 
 // https://webassembly.github.io/spec/core/binary/modules.html#binary-importsec
 const WASM_CUSTOM_SECTION_ID: u8 = 0;
diff --git a/src/librustc_data_structures/Cargo.toml b/src/librustc_data_structures/Cargo.toml
index 79cbe26e73e..288676ce3ff 100644
--- a/src/librustc_data_structures/Cargo.toml
+++ b/src/librustc_data_structures/Cargo.toml
@@ -15,7 +15,7 @@ indexmap = "1"
 log = "0.4"
 jobserver_crate = { version = "0.1.13", package = "jobserver" }
 lazy_static = "1"
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 graphviz = { path = "../libgraphviz" }
 cfg-if = "0.1.2"
 crossbeam-utils = { version = "0.6.5", features = ["nightly"] }
diff --git a/src/librustc_data_structures/fingerprint.rs b/src/librustc_data_structures/fingerprint.rs
index 3bea965ef30..c8012bb9424 100644
--- a/src/librustc_data_structures/fingerprint.rs
+++ b/src/librustc_data_structures/fingerprint.rs
@@ -1,7 +1,6 @@
 use crate::stable_hasher;
 use std::mem;
-use serialize;
-use serialize::opaque::{EncodeResult, Encoder, Decoder};
+use rustc_serialize::opaque::{EncodeResult, Encoder, Decoder};
 
 #[derive(Eq, PartialEq, Ord, PartialOrd, Hash, Debug, Clone, Copy)]
 pub struct Fingerprint(u64, u64);
@@ -85,17 +84,17 @@ fn finish(hasher: stable_hasher::StableHasher<Self>) -> Self {
 
 impl_stable_hash_via_hash!(Fingerprint);
 
-impl serialize::UseSpecializedEncodable for Fingerprint { }
+impl rustc_serialize::UseSpecializedEncodable for Fingerprint { }
 
-impl serialize::UseSpecializedDecodable for Fingerprint { }
+impl rustc_serialize::UseSpecializedDecodable for Fingerprint { }
 
-impl serialize::SpecializedEncoder<Fingerprint> for serialize::opaque::Encoder {
+impl rustc_serialize::SpecializedEncoder<Fingerprint> for Encoder {
     fn specialized_encode(&mut self, f: &Fingerprint) -> Result<(), Self::Error> {
         f.encode_opaque(self)
     }
 }
 
-impl<'a> serialize::SpecializedDecoder<Fingerprint> for serialize::opaque::Decoder<'a> {
+impl<'a> rustc_serialize::SpecializedDecoder<Fingerprint> for Decoder<'a> {
     fn specialized_decode(&mut self) -> Result<Fingerprint, Self::Error> {
         Fingerprint::decode_opaque(self)
     }
diff --git a/src/librustc_data_structures/indexed_vec.rs b/src/librustc_data_structures/indexed_vec.rs
index c3c76e81606..6f40d059be2 100644
--- a/src/librustc_data_structures/indexed_vec.rs
+++ b/src/librustc_data_structures/indexed_vec.rs
@@ -1,3 +1,5 @@
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
+
 use std::fmt::Debug;
 use std::iter::{self, FromIterator};
 use std::slice;
@@ -8,8 +10,6 @@
 use std::vec;
 use std::u32;
 
-use rustc_serialize as serialize;
-
 /// Represents some newtyped `usize` wrapper.
 ///
 /// Purpose: avoid mixing indexes for different bitvector domains.
@@ -398,17 +398,9 @@ fn fmt(&self, fmt: &mut ::std::fmt::Formatter<'_>) -> ::std::fmt::Result {
     );
 
     (@decodable $type:ident) => (
-        impl $type {
-            fn __decodable__impl__hack() {
-                mod __more_hacks_because__self_doesnt_work_in_functions {
-                    extern crate serialize;
-                    use self::serialize::{Decodable, Decoder};
-                    impl Decodable for super::$type {
-                        fn decode<D: Decoder>(d: &mut D) -> Result<Self, D::Error> {
-                            d.read_u32().map(Self::from)
-                        }
-                    }
-                }
+        impl ::rustc_serialize::Decodable for $type {
+            fn decode<D: ::rustc_serialize::Decoder>(d: &mut D) -> Result<Self, D::Error> {
+                d.read_u32().map(Self::from)
             }
         }
     );
@@ -521,15 +513,15 @@ pub struct IndexVec<I: Idx, T> {
 // not the phantom data.
 unsafe impl<I: Idx, T> Send for IndexVec<I, T> where T: Send {}
 
-impl<I: Idx, T: serialize::Encodable> serialize::Encodable for IndexVec<I, T> {
-    fn encode<S: serialize::Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
-        serialize::Encodable::encode(&self.raw, s)
+impl<I: Idx, T: Encodable> Encodable for IndexVec<I, T> {
+    fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+        Encodable::encode(&self.raw, s)
     }
 }
 
-impl<I: Idx, T: serialize::Decodable> serialize::Decodable for IndexVec<I, T> {
-    fn decode<D: serialize::Decoder>(d: &mut D) -> Result<Self, D::Error> {
-        serialize::Decodable::decode(d).map(|v| {
+impl<I: Idx, T: Decodable> Decodable for IndexVec<I, T> {
+    fn decode<D: Decoder>(d: &mut D) -> Result<Self, D::Error> {
+        Decodable::decode(d).map(|v| {
             IndexVec { raw: v, _marker: PhantomData }
         })
     }
diff --git a/src/librustc_data_structures/lib.rs b/src/librustc_data_structures/lib.rs
index a2407681e6d..3047119029a 100644
--- a/src/librustc_data_structures/lib.rs
+++ b/src/librustc_data_structures/lib.rs
@@ -31,8 +31,6 @@
 
 #[macro_use]
 extern crate log;
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
 #[cfg(unix)]
 extern crate libc;
 #[macro_use]
diff --git a/src/librustc_data_structures/svh.rs b/src/librustc_data_structures/svh.rs
index df4f6176837..3123c182b0f 100644
--- a/src/librustc_data_structures/svh.rs
+++ b/src/librustc_data_structures/svh.rs
@@ -7,7 +7,7 @@
 
 use std::fmt;
 use std::hash::{Hash, Hasher};
-use serialize::{Encodable, Decodable, Encoder, Decoder};
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
 
 use crate::stable_hasher;
 
diff --git a/src/librustc_driver/Cargo.toml b/src/librustc_driver/Cargo.toml
index d4c30dc6c45..3162af5086d 100644
--- a/src/librustc_driver/Cargo.toml
+++ b/src/librustc_driver/Cargo.toml
@@ -34,7 +34,7 @@ rustc_traits = { path = "../librustc_traits" }
 rustc_codegen_utils = { path = "../librustc_codegen_utils" }
 rustc_typeck = { path = "../librustc_typeck" }
 rustc_interface = { path = "../librustc_interface" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax = { path = "../libsyntax" }
 smallvec = { version = "0.6.7", features = ["union", "may_dangle"] }
 syntax_ext = { path = "../libsyntax_ext" }
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index 2bc79e5080f..c139be07aa1 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -46,7 +46,7 @@
 use rustc_interface::util::get_codegen_sysroot;
 use rustc_data_structures::sync::SeqCst;
 
-use serialize::json::ToJson;
+use rustc_serialize::json::ToJson;
 
 use std::borrow::Cow;
 use std::cmp::max;
diff --git a/src/librustc_errors/Cargo.toml b/src/librustc_errors/Cargo.toml
index 4df9632cce2..5a192e472aa 100644
--- a/src/librustc_errors/Cargo.toml
+++ b/src/librustc_errors/Cargo.toml
@@ -11,7 +11,7 @@ doctest = false
 
 [dependencies]
 log = "0.4"
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax_pos = { path = "../libsyntax_pos" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 unicode-width = "0.1.4"
diff --git a/src/librustc_errors/lib.rs b/src/librustc_errors/lib.rs
index 3269b85d0dd..0a6c02c0ca6 100644
--- a/src/librustc_errors/lib.rs
+++ b/src/librustc_errors/lib.rs
@@ -12,9 +12,6 @@
 #![deny(rust_2018_idioms)]
 #![deny(unused_lifetimes)]
 
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
-
 pub use emitter::ColorConfig;
 
 use Level::*;
diff --git a/src/librustc_incremental/Cargo.toml b/src/librustc_incremental/Cargo.toml
index 9678cb4f655..a931ad3b66e 100644
--- a/src/librustc_incremental/Cargo.toml
+++ b/src/librustc_incremental/Cargo.toml
@@ -15,7 +15,7 @@ log = "0.4"
 rand = "0.6"
 rustc = { path = "../librustc" }
 rustc_data_structures = { path = "../librustc_data_structures" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
 rustc_fs_util = { path = "../librustc_fs_util" }
diff --git a/src/librustc_incremental/lib.rs b/src/librustc_incremental/lib.rs
index 569aa78c9d4..55aba7caa9d 100644
--- a/src/librustc_incremental/lib.rs
+++ b/src/librustc_incremental/lib.rs
@@ -12,9 +12,6 @@
 #![deny(unused_lifetimes)]
 
 #[macro_use] extern crate rustc;
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
-
 #[macro_use] extern crate log;
 
 mod assert_dep_graph;
diff --git a/src/librustc_interface/Cargo.toml b/src/librustc_interface/Cargo.toml
index a0efec5ee7a..a90254e7e18 100644
--- a/src/librustc_interface/Cargo.toml
+++ b/src/librustc_interface/Cargo.toml
@@ -16,7 +16,7 @@ smallvec = { version = "0.6.7", features = ["union", "may_dangle"] }
 syntax = { path = "../libsyntax" }
 syntax_ext = { path = "../libsyntax_ext" }
 syntax_pos = { path = "../libsyntax_pos" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 rustc = { path = "../librustc" }
 rustc_allocator = { path = "../librustc_allocator" }
 rustc_ast_borrowck = { path = "../librustc_ast_borrowck" }
diff --git a/src/librustc_interface/passes.rs b/src/librustc_interface/passes.rs
index 6bf56bf8515..5298f99d548 100644
--- a/src/librustc_interface/passes.rs
+++ b/src/librustc_interface/passes.rs
@@ -51,7 +51,7 @@
 use syntax_pos::{FileName, edition::Edition, hygiene};
 use syntax_ext;
 
-use serialize::json;
+use rustc_serialize::json;
 use tempfile::Builder as TempFileBuilder;
 
 use std::any::Any;
diff --git a/src/librustc_interface/queries.rs b/src/librustc_interface/queries.rs
index 570509ffb2b..9b79dc6350c 100644
--- a/src/librustc_interface/queries.rs
+++ b/src/librustc_interface/queries.rs
@@ -15,7 +15,7 @@
 use rustc::dep_graph::DepGraph;
 use rustc_passes::hir_stats;
 use rustc_plugin::registry::Registry;
-use serialize::json;
+use rustc_serialize::json;
 use std::cell::{Ref, RefMut, RefCell};
 use std::ops::Deref;
 use std::rc::Rc;
diff --git a/src/librustc_metadata/Cargo.toml b/src/librustc_metadata/Cargo.toml
index e5c9f1bf205..a9f054d5e8b 100644
--- a/src/librustc_metadata/Cargo.toml
+++ b/src/librustc_metadata/Cargo.toml
@@ -18,7 +18,7 @@ rustc = { path = "../librustc" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 errors = { path = "../librustc_errors", package = "rustc_errors" }
 rustc_target = { path = "../librustc_target" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 stable_deref_trait = "1.0.0"
 syntax = { path = "../libsyntax" }
 syntax_ext = { path = "../libsyntax_ext" }
diff --git a/src/librustc_metadata/lib.rs b/src/librustc_metadata/lib.rs
index 826349362db..b0fe06039f4 100644
--- a/src/librustc_metadata/lib.rs
+++ b/src/librustc_metadata/lib.rs
@@ -18,8 +18,6 @@
 #![deny(unused_lifetimes)]
 
 extern crate libc;
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
 extern crate proc_macro;
 
 #[macro_use]
diff --git a/src/librustc_metadata/schema.rs b/src/librustc_metadata/schema.rs
index 8d1de4fd6c3..b7dd1d03e44 100644
--- a/src/librustc_metadata/schema.rs
+++ b/src/librustc_metadata/schema.rs
@@ -13,7 +13,6 @@
 use rustc_target::spec::{PanicStrategy, TargetTriple};
 use rustc_data_structures::svh::Svh;
 
-use rustc_serialize as serialize;
 use syntax::{ast, attr};
 use syntax::edition::Edition;
 use syntax::symbol::Symbol;
@@ -85,8 +84,8 @@ fn clone(&self) -> Self {
     }
 }
 
-impl<T> serialize::UseSpecializedEncodable for Lazy<T> {}
-impl<T> serialize::UseSpecializedDecodable for Lazy<T> {}
+impl<T> rustc_serialize::UseSpecializedEncodable for Lazy<T> {}
+impl<T> rustc_serialize::UseSpecializedDecodable for Lazy<T> {}
 
 /// A sequence of type T referred to by its absolute position
 /// in the metadata and length, and which can be decoded lazily.
@@ -133,8 +132,8 @@ fn clone(&self) -> Self {
     }
 }
 
-impl<T> serialize::UseSpecializedEncodable for LazySeq<T> {}
-impl<T> serialize::UseSpecializedDecodable for LazySeq<T> {}
+impl<T> rustc_serialize::UseSpecializedEncodable for LazySeq<T> {}
+impl<T> rustc_serialize::UseSpecializedDecodable for LazySeq<T> {}
 
 /// Encoding / decoding state for `Lazy` and `LazySeq`.
 #[derive(Copy, Clone, PartialEq, Eq, Debug)]
diff --git a/src/librustc_mir/Cargo.toml b/src/librustc_mir/Cargo.toml
index 2adbd03b24f..21008c73728 100644
--- a/src/librustc_mir/Cargo.toml
+++ b/src/librustc_mir/Cargo.toml
@@ -20,7 +20,7 @@ rustc = { path = "../librustc" }
 rustc_target = { path = "../librustc_target" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 rustc_errors = { path = "../librustc_errors" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
 byteorder = { version = "1.1", features = ["i128"] }
diff --git a/src/librustc_mir/lib.rs b/src/librustc_mir/lib.rs
index f5e4661afa6..964f04d79b9 100644
--- a/src/librustc_mir/lib.rs
+++ b/src/librustc_mir/lib.rs
@@ -30,13 +30,9 @@
 #![deny(unused_lifetimes)]
 
 #[macro_use] extern crate log;
-#[macro_use]
-extern crate rustc;
+#[macro_use] extern crate rustc;
 #[macro_use] extern crate rustc_data_structures;
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
-#[macro_use]
-extern crate syntax;
+#[macro_use] extern crate syntax;
 
 mod error_codes;
 
diff --git a/src/librustc_target/Cargo.toml b/src/librustc_target/Cargo.toml
index f1b21365e4b..cab1e0e0137 100644
--- a/src/librustc_target/Cargo.toml
+++ b/src/librustc_target/Cargo.toml
@@ -12,5 +12,5 @@ path = "lib.rs"
 bitflags = "1.0"
 log = "0.4"
 rustc_data_structures = { path = "../librustc_data_structures" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax_pos = { path = "../libsyntax_pos" }
diff --git a/src/librustc_target/lib.rs b/src/librustc_target/lib.rs
index dcd1eb5acdc..a14bc66cc38 100644
--- a/src/librustc_target/lib.rs
+++ b/src/librustc_target/lib.rs
@@ -18,8 +18,5 @@
 
 #[macro_use] extern crate log;
 
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
-
 pub mod abi;
 pub mod spec;
diff --git a/src/librustc_target/spec/mod.rs b/src/librustc_target/spec/mod.rs
index 1fdc9b015ba..cda0dbef843 100644
--- a/src/librustc_target/spec/mod.rs
+++ b/src/librustc_target/spec/mod.rs
@@ -34,7 +34,7 @@
 //! the target's settings, though `target-feature` and `link-args` will *add*
 //! to the list specified by the target, rather than replace.
 
-use serialize::json::{Json, ToJson};
+use rustc_serialize::json::{Json, ToJson};
 use std::collections::BTreeMap;
 use std::default::Default;
 use std::{fmt, io};
@@ -306,7 +306,7 @@ pub fn get_targets() -> impl Iterator<Item = String> {
 
         #[cfg(test)]
         mod test_json_encode_decode {
-            use serialize::json::ToJson;
+            use rustc_serialize::json::ToJson;
             use super::Target;
             $(use super::$module;)+
 
@@ -1198,7 +1198,7 @@ macro_rules! key {
     pub fn search(target_triple: &TargetTriple) -> Result<Target, String> {
         use std::env;
         use std::fs;
-        use serialize::json;
+        use rustc_serialize::json;
 
         fn load_file(path: &Path) -> Result<Target, String> {
             let contents = fs::read(path).map_err(|e| e.to_string())?;
diff --git a/src/libserialize/tests/json.rs b/src/libserialize/tests/json.rs
index 0fe3d4cfd62..3fb6bda679b 100644
--- a/src/libserialize/tests/json.rs
+++ b/src/libserialize/tests/json.rs
@@ -1,4 +1,3 @@
-#[allow(unused_extern_crates)]
 extern crate serialize as rustc_serialize;
 
 use rustc_serialize::{Encodable, Decodable};
diff --git a/src/libserialize/tests/opaque.rs b/src/libserialize/tests/opaque.rs
index 62a8f251244..fff6fc69e78 100644
--- a/src/libserialize/tests/opaque.rs
+++ b/src/libserialize/tests/opaque.rs
@@ -1,4 +1,3 @@
-#[allow(unused_extern_crates)]
 extern crate serialize as rustc_serialize;
 
 use rustc_serialize::{Encodable, Decodable};
diff --git a/src/libsyntax/Cargo.toml b/src/libsyntax/Cargo.toml
index 15c685b3b7b..d4a9acc1569 100644
--- a/src/libsyntax/Cargo.toml
+++ b/src/libsyntax/Cargo.toml
@@ -11,7 +11,7 @@ doctest = false
 
 [dependencies]
 bitflags = "1.0"
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 log = "0.4"
 scoped-tls = "1.0"
 lazy_static = "1.0.0"
diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index b9b43c89346..dbfad3ef7f4 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -22,7 +22,7 @@
 
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::sync::Lrc;
-use serialize::{self, Decoder, Encoder};
+use rustc_serialize::{self, Decoder, Encoder};
 use std::fmt;
 
 pub use rustc_target::abi::FloatTy;
@@ -266,13 +266,13 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
     }
 }
 
-impl serialize::UseSpecializedEncodable for NodeId {
+impl rustc_serialize::UseSpecializedEncodable for NodeId {
     fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
         s.emit_u32(self.as_u32())
     }
 }
 
-impl serialize::UseSpecializedDecodable for NodeId {
+impl rustc_serialize::UseSpecializedDecodable for NodeId {
     fn default_decode<D: Decoder>(d: &mut D) -> Result<NodeId, D::Error> {
         d.read_u32().map(NodeId::from_u32)
     }
@@ -2414,12 +2414,11 @@ pub fn descriptive_variant(&self) -> &str {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use serialize;
 
     // Are ASTs encodable?
     #[test]
     fn check_asts_encodable() {
-        fn assert_encodable<T: serialize::Encodable>() {}
+        fn assert_encodable<T: rustc_serialize::Encodable>() {}
         assert_encodable::<Crate>();
     }
 }
diff --git a/src/libsyntax/lib.rs b/src/libsyntax/lib.rs
index 3dea1977c4d..0507a322a5f 100644
--- a/src/libsyntax/lib.rs
+++ b/src/libsyntax/lib.rs
@@ -24,9 +24,6 @@
 
 #![recursion_limit="256"]
 
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
-
 pub use errors;
 use rustc_data_structures::sync::Lock;
 use rustc_data_structures::bit_set::GrowableBitSet;
diff --git a/src/libsyntax/ptr.rs b/src/libsyntax/ptr.rs
index be580dc2e6a..b5eb8ca94c0 100644
--- a/src/libsyntax/ptr.rs
+++ b/src/libsyntax/ptr.rs
@@ -31,7 +31,7 @@
 use std::ops::{Deref, DerefMut};
 use std::{slice, vec};
 
-use serialize::{Encodable, Decodable, Encoder, Decoder};
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
 
 use rustc_data_structures::stable_hasher::{StableHasher, StableHasherResult,
                                            HashStable};
diff --git a/src/libsyntax/tokenstream.rs b/src/libsyntax/tokenstream.rs
index 88142344d79..34e68944926 100644
--- a/src/libsyntax/tokenstream.rs
+++ b/src/libsyntax/tokenstream.rs
@@ -23,7 +23,7 @@
 #[cfg(target_arch = "x86_64")]
 use rustc_data_structures::static_assert_size;
 use rustc_data_structures::sync::Lrc;
-use serialize::{Decoder, Decodable, Encoder, Encodable};
+use rustc_serialize::{Decoder, Decodable, Encoder, Encodable};
 use smallvec::{SmallVec, smallvec};
 
 use std::borrow::Cow;
diff --git a/src/libsyntax_pos/Cargo.toml b/src/libsyntax_pos/Cargo.toml
index eebd25d1faf..bc13d2a1611 100644
--- a/src/libsyntax_pos/Cargo.toml
+++ b/src/libsyntax_pos/Cargo.toml
@@ -10,7 +10,7 @@ path = "lib.rs"
 doctest = false
 
 [dependencies]
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 rustc_macros = { path = "../librustc_macros" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 arena = { path = "../libarena" }
diff --git a/src/libsyntax_pos/hygiene.rs b/src/libsyntax_pos/hygiene.rs
index 944b1da36d0..a96e5ef2323 100644
--- a/src/libsyntax_pos/hygiene.rs
+++ b/src/libsyntax_pos/hygiene.rs
@@ -30,7 +30,7 @@
 use crate::edition::Edition;
 use crate::symbol::{kw, Symbol};
 
-use serialize::{Encodable, Decodable, Encoder, Decoder};
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::Lrc;
 use std::fmt;
diff --git a/src/libsyntax_pos/lib.rs b/src/libsyntax_pos/lib.rs
index b9a062c0765..e5f0892b37b 100644
--- a/src/libsyntax_pos/lib.rs
+++ b/src/libsyntax_pos/lib.rs
@@ -19,10 +19,7 @@
 #![feature(specialization)]
 #![feature(step_trait)]
 
-use serialize::{Encodable, Decodable, Encoder, Decoder};
-
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
 
 pub mod edition;
 use edition::Edition;
@@ -594,7 +591,7 @@ fn default() -> Self {
     }
 }
 
-impl serialize::UseSpecializedEncodable for Span {
+impl rustc_serialize::UseSpecializedEncodable for Span {
     fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
         let span = self.data();
         s.emit_struct("Span", 2, |s| {
@@ -609,7 +606,7 @@ fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
     }
 }
 
-impl serialize::UseSpecializedDecodable for Span {
+impl rustc_serialize::UseSpecializedDecodable for Span {
     fn default_decode<D: Decoder>(d: &mut D) -> Result<Span, D::Error> {
         d.read_struct("Span", 2, |d| {
             let lo = d.read_struct_field("lo", 0, Decodable::decode)?;
diff --git a/src/libsyntax_pos/symbol.rs b/src/libsyntax_pos/symbol.rs
index f23ed7371c6..308f7d5d4e3 100644
--- a/src/libsyntax_pos/symbol.rs
+++ b/src/libsyntax_pos/symbol.rs
@@ -7,7 +7,7 @@
 use rustc_data_structures::indexed_vec::Idx;
 use rustc_data_structures::newtype_index;
 use rustc_macros::symbols;
-use serialize::{Decodable, Decoder, Encodable, Encoder};
+use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
 
 use std::cmp::{PartialEq, Ordering, PartialOrd, Ord};
 use std::fmt;