Remove extern crate rustc_macros from numerous crates.

compiler/rustc_ast/src/ast.rs

@@ -32,7 +32,7 @@ use rustc_data_structures::packed::Pu128;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_data_structures::sync::Lrc;
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::source_map::{respan, Spanned};
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{ErrorGuaranteed, Span, DUMMY_SP};

compiler/rustc_ast/src/expand/allocator.rs

@@ -1,3 +1,4 @@
+use rustc_macros::HashStable_Generic;
 use rustc_span::symbol::{sym, Symbol};
 
 #[derive(Clone, Debug, Copy, Eq, PartialEq, HashStable_Generic)]

compiler/rustc_ast/src/expand/mod.rs

@@ -1,5 +1,6 @@
 //! Definitions shared by macros / syntax extensions and e.g. `rustc_middle`.
 
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::{def_id::DefId, symbol::Ident};
 
 use crate::MetaItem;

compiler/rustc_ast/src/format.rs

@@ -1,6 +1,7 @@
 use crate::ptr::P;
 use crate::Expr;
 use rustc_data_structures::fx::FxHashMap;
+use rustc_macros::{Decodable, Encodable};
 use rustc_span::symbol::{Ident, Symbol};
 use rustc_span::Span;
 

compiler/rustc_ast/src/lib.rs

@@ -20,9 +20,6 @@
 #![feature(negative_impls)]
 #![feature(stmt_expr_attributes)]
 
-#[macro_use]
-extern crate rustc_macros;
-
 #[macro_use]
 extern crate tracing;
 

compiler/rustc_ast/src/token.rs

@@ -9,7 +9,7 @@ use crate::util::case::Case;
 
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::sync::Lrc;
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::symbol::{kw, sym};
 #[allow(clippy::useless_attribute)] // FIXME: following use of `hidden_glob_reexports` incorrectly triggers `useless_attribute` lint.
 #[allow(hidden_glob_reexports)]

compiler/rustc_ast/src/tokenstream.rs

@@ -20,7 +20,7 @@ use crate::AttrVec;
 
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::sync::{self, Lrc};
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_serialize::{Decodable, Encodable};
 use rustc_span::{sym, Span, SpanDecoder, SpanEncoder, Symbol, DUMMY_SP};
 use smallvec::{smallvec, SmallVec};

compiler/rustc_ast_ir/src/lib.rs

@@ -3,8 +3,7 @@
 #![cfg_attr(feature = "nightly", allow(internal_features))]
 
 #[cfg(feature = "nightly")]
-#[macro_use]
-extern crate rustc_macros;
+use rustc_macros::{Decodable, Encodable, HashStable_NoContext};
 
 pub mod visit;
 

compiler/rustc_attr/src/builtin.rs

@@ -6,7 +6,7 @@ use rustc_ast::{Attribute, LitKind, MetaItem, MetaItemKind, MetaItemLit, NestedM
 use rustc_ast_pretty::pprust;
 use rustc_errors::ErrorGuaranteed;
 use rustc_feature::{find_gated_cfg, is_builtin_attr_name, Features, GatedCfg};
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_session::config::ExpectedValues;
 use rustc_session::lint::builtin::UNEXPECTED_CFGS;
 use rustc_session::lint::BuiltinLintDiag;

compiler/rustc_attr/src/lib.rs

@@ -9,9 +9,6 @@
 #![doc(rust_logo)]
 #![feature(let_chains)]
 
-#[macro_use]
-extern crate rustc_macros;
-
 mod builtin;
 mod session_diagnostics;
 

compiler/rustc_attr/src/session_diagnostics.rs

@@ -2,7 +2,7 @@ use std::num::IntErrorKind;
 
 use rustc_ast as ast;
 use rustc_errors::{codes::*, Applicability, Diag, DiagCtxt, Diagnostic, EmissionGuarantee, Level};
-use rustc_macros::Diagnostic;
+use rustc_macros::{Diagnostic, Subdiagnostic};
 use rustc_span::{Span, Symbol};
 
 use crate::fluent_generated as fluent;

compiler/rustc_codegen_llvm/src/debuginfo/metadata/type_map.rs

@@ -5,6 +5,7 @@ use rustc_data_structures::{
     fx::FxHashMap,
     stable_hasher::{HashStable, StableHasher},
 };
+use rustc_macros::HashStable;
 use rustc_middle::{
     bug,
     ty::{ParamEnv, PolyExistentialTraitRef, Ty, TyCtxt},
@@ -23,6 +24,8 @@ use crate::{
 use super::{unknown_file_metadata, SmallVec, UNKNOWN_LINE_NUMBER};
 
 mod private {
+    use rustc_macros::HashStable;
+
     // This type cannot be constructed outside of this module because
     // it has a private field. We make use of this in order to prevent
     // `UniqueTypeId` from being constructed directly, without asserting

compiler/rustc_codegen_llvm/src/lib.rs

@@ -15,8 +15,6 @@
 #![feature(let_chains)]
 #![feature(impl_trait_in_assoc_type)]
 
-#[macro_use]
-extern crate rustc_macros;
 #[macro_use]
 extern crate tracing;
 

compiler/rustc_codegen_ssa/src/lib.rs

@@ -16,8 +16,6 @@
 //! The backend-agnostic functions of this crate use functions defined in various traits that
 //! have to be implemented by each backend.
 
-#[macro_use]
-extern crate rustc_macros;
 #[macro_use]
 extern crate tracing;
 #[macro_use]
@@ -29,6 +27,7 @@ use rustc_data_structures::fx::FxIndexMap;
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::unord::UnordMap;
 use rustc_hir::def_id::CrateNum;
+use rustc_macros::{Decodable, Encodable, HashStable};
 use rustc_middle::dep_graph::WorkProduct;
 use rustc_middle::middle::debugger_visualizer::DebuggerVisualizerFile;
 use rustc_middle::middle::dependency_format::Dependencies;

compiler/rustc_data_structures/src/lib.rs

@@ -41,8 +41,6 @@
 
 #[macro_use]
 extern crate tracing;
-#[macro_use]
-extern crate rustc_macros;
 
 use std::fmt;
 

compiler/rustc_data_structures/src/sorted_map.rs

@@ -1,4 +1,5 @@
 use crate::stable_hasher::{HashStable, StableHasher, StableOrd};
+use rustc_macros::{Decodable_Generic, Encodable_Generic};
 use std::borrow::Borrow;
 use std::fmt::Debug;
 use std::mem;

compiler/rustc_data_structures/src/svh.rs

@@ -6,9 +6,9 @@
 //! compiled from distinct sources.
 
 use crate::fingerprint::Fingerprint;
-use std::fmt;
-
 use crate::stable_hasher;
+use rustc_macros::{Decodable_Generic, Encodable_Generic};
+use std::fmt;
 
 #[derive(Copy, Clone, PartialEq, Eq, Debug, Encodable_Generic, Decodable_Generic, Hash)]
 pub struct Svh {

compiler/rustc_data_structures/src/unord.rs

@@ -3,6 +3,7 @@
 //! as required by the query system.
 
 use rustc_hash::{FxHashMap, FxHashSet};
+use rustc_macros::{Decodable_Generic, Encodable_Generic};
 use std::{
     borrow::{Borrow, BorrowMut},
     collections::hash_map::Entry,

compiler/rustc_errors/src/diagnostic.rs

@@ -7,6 +7,7 @@ use rustc_data_structures::fx::FxIndexMap;
 use rustc_error_messages::fluent_value_from_str_list_sep_by_and;
 use rustc_error_messages::FluentValue;
 use rustc_lint_defs::{Applicability, LintExpectationId};
+use rustc_macros::{Decodable, Encodable};
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::Symbol;
 use rustc_span::{Span, DUMMY_SP};

compiler/rustc_errors/src/diagnostic_impls.rs

@@ -7,6 +7,7 @@ use crate::{
 use rustc_ast as ast;
 use rustc_ast_pretty::pprust;
 use rustc_hir as hir;
+use rustc_macros::Subdiagnostic;
 use rustc_span::edition::Edition;
 use rustc_span::symbol::{Ident, MacroRulesNormalizedIdent, Symbol};
 use rustc_span::Span;

compiler/rustc_errors/src/lib.rs

@@ -25,9 +25,6 @@
 #![feature(yeet_expr)]
 // tidy-alphabetical-end
 
-#[macro_use]
-extern crate rustc_macros;
-
 #[macro_use]
 extern crate tracing;
 
@@ -64,6 +61,7 @@ use rustc_data_structures::stable_hasher::{Hash128, StableHasher};
 use rustc_data_structures::sync::{Lock, Lrc};
 use rustc_data_structures::AtomicRef;
 use rustc_lint_defs::LintExpectationId;
+use rustc_macros::{Decodable, Encodable};
 use rustc_span::source_map::SourceMap;
 use rustc_span::{Loc, Span, DUMMY_SP};
 use std::backtrace::{Backtrace, BacktraceStatus};

compiler/rustc_errors/src/snippet.rs

@@ -1,6 +1,7 @@
 // Code for annotating snippets.
 
 use crate::{Level, Loc};
+use rustc_macros::{Decodable, Encodable};
 
 #[derive(Clone, Debug, PartialOrd, Ord, PartialEq, Eq)]
 pub struct Line {

compiler/rustc_expand/src/errors.rs

@@ -1,6 +1,6 @@
 use rustc_ast::ast;
 use rustc_errors::codes::*;
-use rustc_macros::Diagnostic;
+use rustc_macros::{Diagnostic, Subdiagnostic};
 use rustc_session::Limit;
 use rustc_span::symbol::{Ident, MacroRulesNormalizedIdent};
 use rustc_span::{Span, Symbol};

compiler/rustc_expand/src/lib.rs

@@ -16,9 +16,6 @@
 #![allow(rustc::diagnostic_outside_of_impl)]
 #![allow(internal_features)]
 
-#[macro_use]
-extern crate rustc_macros;
-
 #[macro_use]
 extern crate tracing;
 

compiler/rustc_expand/src/mbe.rs

@@ -14,6 +14,7 @@ pub(crate) mod transcribe;
 use metavar_expr::MetaVarExpr;
 use rustc_ast::token::{Delimiter, NonterminalKind, Token, TokenKind};
 use rustc_ast::tokenstream::{DelimSpacing, DelimSpan};
+use rustc_macros::{Decodable, Encodable};
 use rustc_span::symbol::Ident;
 use rustc_span::Span;
 

compiler/rustc_expand/src/mbe/diagnostics.rs

@@ -8,6 +8,7 @@ use rustc_ast::token::{self, Token, TokenKind};
 use rustc_ast::tokenstream::TokenStream;
 use rustc_ast_pretty::pprust;
 use rustc_errors::{Applicability, Diag, DiagCtxt, DiagMessage};
+use rustc_macros::Subdiagnostic;
 use rustc_parse::parser::{Parser, Recovery};
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::Ident;

compiler/rustc_expand/src/mbe/metavar_expr.rs

@@ -3,6 +3,7 @@ use rustc_ast::tokenstream::{RefTokenTreeCursor, TokenStream, TokenTree};
 use rustc_ast::{LitIntType, LitKind};
 use rustc_ast_pretty::pprust;
 use rustc_errors::{Applicability, PResult};
+use rustc_macros::{Decodable, Encodable};
 use rustc_session::parse::ParseSess;
 use rustc_span::symbol::Ident;
 use rustc_span::Span;

compiler/rustc_hir/src/def.rs

@@ -5,7 +5,7 @@ use rustc_ast as ast;
 use rustc_ast::NodeId;
 use rustc_data_structures::stable_hasher::ToStableHashKey;
 use rustc_data_structures::unord::UnordMap;
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::def_id::{DefId, LocalDefId};
 use rustc_span::hygiene::MacroKind;
 use rustc_span::symbol::kw;

compiler/rustc_hir/src/definitions.rs

@@ -11,6 +11,7 @@ use crate::def_path_hash_map::DefPathHashMap;
 use rustc_data_structures::stable_hasher::{Hash64, StableHasher};
 use rustc_data_structures::unord::UnordMap;
 use rustc_index::IndexVec;
+use rustc_macros::{Decodable, Encodable};
 use rustc_span::symbol::{kw, sym, Symbol};
 
 use std::fmt::{self, Write};

compiler/rustc_hir/src/hir.rs

@@ -13,7 +13,7 @@ use rustc_ast::{InlineAsmOptions, InlineAsmTemplatePiece};
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::sorted_map::SortedMap;
 use rustc_index::IndexVec;
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::hygiene::MacroKind;
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};

compiler/rustc_hir/src/hir_id.rs

@@ -1,5 +1,6 @@
 use crate::def_id::{DefId, DefIndex, LocalDefId, CRATE_DEF_ID};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher, StableOrd, ToStableHashKey};
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::{def_id::DefPathHash, HashStableContext};
 use std::fmt::{self, Debug};
 

compiler/rustc_hir/src/lang_items.rs

@@ -12,7 +12,7 @@ use crate::{MethodKind, Target};
 
 use rustc_ast as ast;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
 

compiler/rustc_hir/src/lib.rs

@@ -10,9 +10,6 @@
 #![feature(variant_count)]
 #![allow(internal_features)]
 
-#[macro_use]
-extern crate rustc_macros;
-
 #[macro_use]
 extern crate tracing;
 

compiler/rustc_infer/src/infer/canonical/instantiate.rs

@@ -7,6 +7,7 @@
 //! [c]: https://rust-lang.github.io/chalk/book/canonical_queries/canonicalization.html
 
 use crate::infer::canonical::{Canonical, CanonicalVarValues};
+use rustc_macros::extension;
 use rustc_middle::ty::fold::{FnMutDelegate, TypeFoldable};
 use rustc_middle::ty::GenericArgKind;
 use rustc_middle::ty::{self, TyCtxt};

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -68,6 +68,7 @@ use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::intravisit::Visitor;
 use rustc_hir::lang_items::LangItem;
+use rustc_macros::extension;
 use rustc_middle::dep_graph::DepContext;
 use rustc_middle::ty::print::{with_forced_trimmed_paths, PrintError};
 use rustc_middle::ty::relate::{self, RelateResult, TypeRelation};

compiler/rustc_infer/src/infer/mod.rs

@@ -4,6 +4,7 @@ pub use lexical_region_resolve::RegionResolutionError;
 pub use relate::combine::CombineFields;
 pub use relate::combine::ObligationEmittingRelation;
 pub use relate::StructurallyRelateAliases;
+pub use rustc_macros::{TypeFoldable, TypeVisitable};
 pub use rustc_middle::ty::IntVarValue;
 pub use BoundRegionConversionTime::*;
 pub use RegionVariableOrigin::*;
@@ -20,13 +21,13 @@ use opaque_types::OpaqueTypeStorage;
 use region_constraints::{GenericKind, VarInfos, VerifyBound};
 use region_constraints::{RegionConstraintCollector, RegionConstraintStorage};
 use rustc_data_structures::captures::Captures;
-use rustc_data_structures::fx::FxIndexMap;
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap};
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::undo_log::Rollback;
 use rustc_data_structures::unify as ut;
 use rustc_errors::{Diag, DiagCtxt, ErrorGuaranteed};
 use rustc_hir::def_id::{DefId, LocalDefId};
+use rustc_macros::extension;
 use rustc_middle::infer::canonical::{Canonical, CanonicalVarValues};
 use rustc_middle::infer::unify_key::ConstVariableValue;
 use rustc_middle::infer::unify_key::EffectVarValue;

compiler/rustc_infer/src/infer/region_constraints/mod.rs

@@ -11,6 +11,7 @@ use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::undo_log::UndoLogs;
 use rustc_data_structures::unify as ut;
 use rustc_index::IndexVec;
+use rustc_macros::{TypeFoldable, TypeVisitable};
 use rustc_middle::infer::unify_key::{RegionVariableValue, RegionVidKey};
 use rustc_middle::ty::ReStatic;
 use rustc_middle::ty::{self, Ty, TyCtxt};

compiler/rustc_infer/src/lib.rs

@@ -30,8 +30,6 @@
 #![feature(yeet_expr)]
 #![recursion_limit = "512"] // For rustdoc
 
-#[macro_use]
-extern crate rustc_macros;
 #[cfg(target_pointer_width = "64")]
 #[macro_use]
 extern crate rustc_data_structures;

compiler/rustc_infer/src/traits/engine.rs

@@ -1,6 +1,7 @@
 use crate::infer::InferCtxt;
 use crate::traits::Obligation;
 use rustc_hir::def_id::DefId;
+use rustc_macros::extension;
 use rustc_middle::ty::{self, ToPredicate, Ty};
 
 use super::FulfillmentError;

compiler/rustc_lint_defs/src/lib.rs

@@ -1,6 +1,3 @@
-#[macro_use]
-extern crate rustc_macros;
-
 pub use self::Level::*;
 use rustc_ast::node_id::NodeId;
 use rustc_ast::{AttrId, Attribute};
@@ -11,6 +8,7 @@ use rustc_data_structures::stable_hasher::{
 use rustc_error_messages::{DiagMessage, MultiSpan};
 use rustc_hir::HashStableContext;
 use rustc_hir::HirId;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::edition::Edition;
 use rustc_span::{sym, symbol::Ident, Span, Symbol};
 use rustc_target::spec::abi::Abi;

compiler/rustc_metadata/src/errors.rs

@@ -4,7 +4,7 @@ use std::{
 };
 
 use rustc_errors::{codes::*, Diag, DiagCtxt, Diagnostic, EmissionGuarantee, Level};
-use rustc_macros::Diagnostic;
+use rustc_macros::{Diagnostic, Subdiagnostic};
 use rustc_session::config;
 use rustc_span::{sym, Span, Symbol};
 use rustc_target::spec::{PanicStrategy, TargetTriple};

compiler/rustc_metadata/src/lib.rs

@@ -19,8 +19,6 @@
 
 extern crate proc_macro;
 
-#[macro_use]
-extern crate rustc_macros;
 #[macro_use]
 extern crate rustc_middle;
 

compiler/rustc_metadata/src/rmeta/mod.rs

@@ -2,6 +2,7 @@ use crate::creader::CrateMetadataRef;
 use decoder::Metadata;
 use def_path_hash_map::DefPathHashMapRef;
 use rustc_data_structures::fx::FxHashMap;
+use rustc_macros::{Decodable, Encodable, TyDecodable, TyEncodable};
 use rustc_middle::middle::debugger_visualizer::DebuggerVisualizerFile;
 use rustc_middle::middle::lib_features::FeatureStability;
 use table::TableBuilder;
@@ -17,6 +18,7 @@ use rustc_hir::definitions::DefKey;
 use rustc_hir::lang_items::LangItem;
 use rustc_index::bit_set::BitSet;
 use rustc_index::IndexVec;
+use rustc_macros::{MetadataDecodable, MetadataEncodable};
 use rustc_middle::metadata::ModChild;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
 use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportInfo};

compiler/rustc_query_system/src/dep_graph/dep_node.rs

@@ -49,6 +49,7 @@ use rustc_data_structures::fingerprint::{Fingerprint, PackedFingerprint};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher, StableOrd, ToStableHashKey};
 use rustc_data_structures::AtomicRef;
 use rustc_hir::definitions::DefPathHash;
+use rustc_macros::{Decodable, Encodable};
 use std::fmt;
 use std::hash::Hash;
 
@@ -285,8 +286,7 @@ pub struct DepKindStruct<Tcx: DepContext> {
 /// some independent path or string that persists between runs without
 /// the need to be mapped or unmapped. (This ensures we can serialize
 /// them even in the absence of a tcx.)
-#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
-#[derive(Encodable, Decodable)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Encodable, Decodable)]
 pub struct WorkProductId {
     hash: Fingerprint,
 }

compiler/rustc_query_system/src/dep_graph/graph.rs

@@ -6,6 +6,7 @@ use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::sync::{AtomicU32, AtomicU64, Lock, Lrc};
 use rustc_data_structures::unord::UnordMap;
 use rustc_index::IndexVec;
+use rustc_macros::{Decodable, Encodable};
 use rustc_serialize::opaque::{FileEncodeResult, FileEncoder};
 use std::assert_matches::assert_matches;
 use std::collections::hash_map::Entry;

compiler/rustc_query_system/src/lib.rs

@@ -9,8 +9,6 @@
 extern crate tracing;
 #[macro_use]
 extern crate rustc_data_structures;
-#[macro_use]
-extern crate rustc_macros;
 
 pub mod cache;
 pub mod dep_graph;

compiler/rustc_query_system/src/query/mod.rs

@@ -20,6 +20,7 @@ use rustc_data_structures::stable_hasher::Hash64;
 use rustc_data_structures::sync::Lock;
 use rustc_errors::DiagInner;
 use rustc_hir::def::DefKind;
+use rustc_macros::{Decodable, Encodable};
 use rustc_span::def_id::DefId;
 use rustc_span::Span;
 use thin_vec::ThinVec;

compiler/rustc_session/src/config.rs

@@ -15,6 +15,7 @@ use rustc_data_structures::stable_hasher::{StableOrd, ToStableHashKey};
 use rustc_errors::emitter::HumanReadableErrorType;
 use rustc_errors::{ColorConfig, DiagArgValue, DiagCtxtFlags, IntoDiagArg};
 use rustc_feature::UnstableFeatures;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::edition::{Edition, DEFAULT_EDITION, EDITION_NAME_LIST, LATEST_STABLE_EDITION};
 use rustc_span::source_map::FilePathMapping;
 use rustc_span::{FileName, FileNameDisplayPreference, RealFileName, SourceFileHashAlgorithm};

compiler/rustc_session/src/cstore.rs

@@ -10,6 +10,7 @@ use rustc_hir::def_id::{
     CrateNum, DefId, LocalDefId, StableCrateId, StableCrateIdMap, LOCAL_CRATE,
 };
 use rustc_hir::definitions::{DefKey, DefPath, DefPathHash, Definitions};
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::symbol::Symbol;
 use rustc_span::Span;
 use rustc_target::spec::abi::Abi;

compiler/rustc_session/src/errors.rs

@@ -6,7 +6,7 @@ use rustc_errors::{
     codes::*, Diag, DiagCtxt, DiagMessage, Diagnostic, EmissionGuarantee, ErrorGuaranteed, Level,
     MultiSpan,
 };
-use rustc_macros::Diagnostic;
+use rustc_macros::{Diagnostic, Subdiagnostic};
 use rustc_span::{Span, Symbol};
 use rustc_target::spec::{SplitDebuginfo, StackProtector, TargetTriple};
 

compiler/rustc_session/src/lib.rs

@@ -6,8 +6,6 @@
 #![feature(iter_intersperse)]
 #![allow(internal_features)]
 
-#[macro_use]
-extern crate rustc_macros;
 pub mod errors;
 
 #[macro_use]

compiler/rustc_session/src/search_paths.rs

@@ -1,5 +1,6 @@
 use crate::filesearch::make_target_lib_path;
 use crate::EarlyDiagCtxt;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_target::spec::TargetTriple;
 use std::path::{Path, PathBuf};
 

compiler/rustc_session/src/utils.rs

@@ -1,6 +1,7 @@
 use crate::session::Session;
 use rustc_data_structures::profiling::VerboseTimingGuard;
 use rustc_fs_util::try_canonicalize;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use std::{
     path::{Path, PathBuf},
     sync::OnceLock,

compiler/rustc_session/src/version.rs

@@ -1,3 +1,4 @@
+use rustc_macros::{current_rustc_version, Decodable, Encodable, HashStable_Generic};
 use std::fmt::{self, Display};
 
 #[derive(Encodable, Decodable, Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]

compiler/rustc_span/src/def_id.rs

@@ -6,7 +6,7 @@ use rustc_data_structures::stable_hasher::{
 use rustc_data_structures::unhash::Unhasher;
 use rustc_data_structures::AtomicRef;
 use rustc_index::Idx;
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_serialize::{Decodable, Encodable};
 use std::fmt;
 use std::hash::{BuildHasherDefault, Hash, Hasher};

compiler/rustc_span/src/edition.rs

@@ -1,7 +1,7 @@
 use std::fmt;
 use std::str::FromStr;
 
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 
 /// The edition of the compiler. (See [RFC 2052](https://github.com/rust-lang/rfcs/blob/master/text/2052-epochs.md).)
 #[derive(Clone, Copy, Hash, PartialEq, PartialOrd, Debug, Encodable, Decodable, Eq)]

compiler/rustc_span/src/hygiene.rs

@@ -34,7 +34,7 @@ use rustc_data_structures::stable_hasher::{Hash64, HashStable, HashingControls,
 use rustc_data_structures::sync::{Lock, Lrc, WorkerLocal};
 use rustc_data_structures::unhash::UnhashMap;
 use rustc_index::IndexVec;
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
 use std::cell::RefCell;
 use std::collections::hash_map::Entry;

compiler/rustc_span/src/lib.rs

@@ -35,14 +35,11 @@
 
 extern crate self as rustc_span;
 
-#[macro_use]
-extern crate rustc_macros;
-
 #[macro_use]
 extern crate tracing;
 
 use rustc_data_structures::{outline, AtomicRef};
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_serialize::opaque::{FileEncoder, MemDecoder};
 use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
 

compiler/rustc_span/src/source_map.rs

@@ -12,6 +12,7 @@
 use crate::*;
 use rustc_data_structures::sync::{IntoDynSyncSend, MappedReadGuard, ReadGuard, RwLock};
 use rustc_data_structures::unhash::UnhashMap;
+use rustc_macros::{Decodable, Encodable};
 use std::fs;
 use std::io::{self, BorrowedBuf, Read};
 use std::path;

compiler/rustc_span/src/symbol.rs

@@ -8,7 +8,7 @@ use rustc_data_structures::stable_hasher::{
     HashStable, StableCompare, StableHasher, ToStableHashKey,
 };
 use rustc_data_structures::sync::Lock;
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{symbols, Decodable, Encodable, HashStable_Generic};
 
 use std::fmt;
 use std::hash::{Hash, Hasher};

compiler/rustc_target/src/abi/call/mod.rs

@@ -1,6 +1,7 @@
 use crate::abi::{self, Abi, Align, FieldsShape, Size};
 use crate::abi::{HasDataLayout, TyAbiInterface, TyAndLayout};
 use crate::spec::{self, HasTargetSpec, HasWasmCAbiOpt};
+use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 use std::str::FromStr;
@@ -100,6 +101,8 @@ pub use attr_impl::ArgAttribute;
 #[allow(non_upper_case_globals)]
 #[allow(unused)]
 mod attr_impl {
+    use rustc_macros::HashStable_Generic;
+
     // The subset of llvm::Attribute needed for arguments, packed into a bitfield.
     #[derive(Clone, Copy, Default, Hash, PartialEq, Eq, HashStable_Generic)]
     pub struct ArgAttribute(u8);

compiler/rustc_target/src/asm/aarch64.rs

@@ -1,7 +1,6 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
 use crate::spec::{RelocModel, Target};
 use rustc_data_structures::fx::FxIndexSet;
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/asm/arm.rs

@@ -1,7 +1,6 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
 use crate::spec::{RelocModel, Target};
 use rustc_data_structures::fx::FxIndexSet;
-use rustc_macros::HashStable_Generic;
 use rustc_span::{sym, Symbol};
 use std::fmt;
 

compiler/rustc_target/src/asm/avr.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/asm/bpf.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/asm/csky.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/asm/hexagon.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/asm/loongarch.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/asm/m68k.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/asm/mips.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/asm/mod.rs

@@ -1,7 +1,7 @@
 use crate::spec::Target;
 use crate::{abi::Size, spec::RelocModel};
 use rustc_data_structures::fx::{FxHashMap, FxIndexSet};
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::Symbol;
 use std::fmt;
 use std::str::FromStr;
@@ -24,7 +24,7 @@ macro_rules! def_reg_class {
             $class:ident,
         )*
     }) => {
-        #[derive(Copy, Clone, Encodable, Decodable, Debug, Eq, PartialEq, PartialOrd, Hash, HashStable_Generic)]
+        #[derive(Copy, Clone, rustc_macros::Encodable, rustc_macros::Decodable, Debug, Eq, PartialEq, PartialOrd, Hash, rustc_macros::HashStable_Generic)]
         #[allow(non_camel_case_types)]
         pub enum $arch_regclass {
             $($class,)*
@@ -73,7 +73,7 @@ macro_rules! def_regs {
         )*
     }) => {
         #[allow(unreachable_code)]
-        #[derive(Copy, Clone, Encodable, Decodable, Debug, Eq, PartialEq, PartialOrd, Hash, HashStable_Generic)]
+        #[derive(Copy, Clone, rustc_macros::Encodable, rustc_macros::Decodable, Debug, Eq, PartialEq, PartialOrd, Hash, rustc_macros::HashStable_Generic)]
         #[allow(non_camel_case_types)]
         pub enum $arch_reg {
             $($reg,)*

compiler/rustc_target/src/asm/msp430.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/asm/nvptx.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 
 def_reg_class! {

compiler/rustc_target/src/asm/powerpc.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/asm/riscv.rs

@@ -1,7 +1,6 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
 use crate::spec::{RelocModel, Target};
 use rustc_data_structures::fx::FxIndexSet;
-use rustc_macros::HashStable_Generic;
 use rustc_span::{sym, Symbol};
 use std::fmt;
 

compiler/rustc_target/src/asm/s390x.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/asm/spirv.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 
 def_reg_class! {

compiler/rustc_target/src/asm/wasm.rs

@@ -1,5 +1,4 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 
 def_reg_class! {

compiler/rustc_target/src/asm/x86.rs

@@ -1,7 +1,6 @@
 use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
 use crate::spec::{RelocModel, Target};
 use rustc_data_structures::fx::FxIndexSet;
-use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
 

compiler/rustc_target/src/lib.rs

@@ -20,9 +20,6 @@
 
 use std::path::{Path, PathBuf};
 
-#[macro_use]
-extern crate rustc_macros;
-
 #[macro_use]
 extern crate tracing;
 

compiler/rustc_target/src/spec/abi/mod.rs

@@ -1,6 +1,6 @@
 use std::fmt;
 
-use rustc_macros::HashStable_Generic;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::symbol::sym;
 use rustc_span::{Span, Symbol};
 

compiler/rustc_target/src/spec/mod.rs

@@ -40,6 +40,7 @@ use crate::json::{Json, ToJson};
 use crate::spec::abi::Abi;
 use crate::spec::crt_objects::CrtObjects;
 use rustc_fs_util::try_canonicalize;
+use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
 use rustc_span::symbol::{kw, sym, Symbol};
 use serde_json::Value;
@@ -51,8 +52,6 @@ use std::path::{Path, PathBuf};
 use std::str::FromStr;
 use std::{fmt, io};
 
-use rustc_macros::HashStable_Generic;
-
 pub mod abi;
 pub mod crt_objects;
 

compiler/rustc_trait_selection/src/errors.rs

@@ -3,7 +3,7 @@ use rustc_errors::{
     codes::*, Applicability, Diag, DiagCtxt, Diagnostic, EmissionGuarantee, Level,
     SubdiagMessageOp, Subdiagnostic,
 };
-use rustc_macros::Diagnostic;
+use rustc_macros::{Diagnostic, Subdiagnostic};
 use rustc_middle::ty::{self, ClosureKind, PolyTraitRef, Ty};
 use rustc_span::{Span, Symbol};
 

compiler/rustc_trait_selection/src/infer.rs

@@ -1,10 +1,9 @@
 use crate::traits::query::evaluate_obligation::InferCtxtExt as _;
-use crate::traits::{self, ObligationCtxt, SelectionContext};
-
-use crate::traits::TraitEngineExt as _;
+use crate::traits::{self, ObligationCtxt, SelectionContext, TraitEngineExt as _};
 use rustc_hir::def_id::DefId;
 use rustc_hir::lang_items::LangItem;
 use rustc_infer::traits::{Obligation, TraitEngine, TraitEngineExt as _};
+use rustc_macros::extension;
 use rustc_middle::arena::ArenaAllocatable;
 use rustc_middle::infer::canonical::{Canonical, CanonicalQueryResponse, QueryResponse};
 use rustc_middle::traits::query::NoSolution;

compiler/rustc_trait_selection/src/lib.rs

@@ -29,8 +29,6 @@
 #![feature(type_alias_impl_trait)]
 #![recursion_limit = "512"] // For rustdoc
 
-#[macro_use]
-extern crate rustc_macros;
 #[cfg(target_pointer_width = "64")]
 #[macro_use]
 extern crate rustc_data_structures;

compiler/rustc_trait_selection/src/regions.rs

@@ -1,5 +1,6 @@
 use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{InferCtxt, RegionResolutionError};
+use rustc_macros::extension;
 use rustc_middle::traits::query::NoSolution;
 use rustc_middle::traits::ObligationCause;
 

compiler/rustc_trait_selection/src/solve/assembly/structural_traits.rs

@@ -4,6 +4,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_hir::LangItem;
 use rustc_hir::{def_id::DefId, Movability, Mutability};
 use rustc_infer::traits::query::NoSolution;
+use rustc_macros::{TypeFoldable, TypeVisitable};
 use rustc_middle::traits::solve::Goal;
 use rustc_middle::ty::{
     self, ToPredicate, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable,

compiler/rustc_trait_selection/src/solve/eval_ctxt/mod.rs

@@ -9,6 +9,7 @@ use rustc_infer::infer::{
 use rustc_infer::traits::query::NoSolution;
 use rustc_infer::traits::solve::{MaybeCause, NestedNormalizationGoals};
 use rustc_infer::traits::ObligationCause;
+use rustc_macros::{extension, HashStable};
 use rustc_middle::infer::canonical::CanonicalVarInfos;
 use rustc_middle::infer::unify_key::ConstVariableOrigin;
 use rustc_middle::traits::solve::inspect;

compiler/rustc_trait_selection/src/solve/eval_ctxt/select.rs

@@ -4,6 +4,7 @@ use rustc_infer::infer::{DefineOpaqueTypes, InferCtxt};
 use rustc_infer::traits::{
     Obligation, PolyTraitObligation, PredicateObligation, Selection, SelectionResult, TraitEngine,
 };
+use rustc_macros::extension;
 use rustc_middle::traits::solve::{CandidateSource, CanonicalInput, Certainty, Goal};
 use rustc_middle::traits::{
     BuiltinImplSource, ImplSource, ImplSourceUserDefinedData, ObligationCause, SelectionError,

compiler/rustc_trait_selection/src/solve/inspect/analyse.rs

@@ -14,6 +14,7 @@ use rustc_ast_ir::visit::VisitorResult;
 use rustc_infer::infer::resolve::EagerResolver;
 use rustc_infer::infer::type_variable::TypeVariableOrigin;
 use rustc_infer::infer::{DefineOpaqueTypes, InferCtxt, InferOk};
+use rustc_macros::extension;
 use rustc_middle::infer::unify_key::ConstVariableOrigin;
 use rustc_middle::traits::query::NoSolution;
 use rustc_middle::traits::solve::{inspect, QueryResult};

compiler/rustc_trait_selection/src/solve/mod.rs

@@ -16,6 +16,7 @@
 use rustc_hir::def_id::DefId;
 use rustc_infer::infer::canonical::{Canonical, CanonicalVarValues};
 use rustc_infer::traits::query::NoSolution;
+use rustc_macros::extension;
 use rustc_middle::infer::canonical::CanonicalVarInfos;
 use rustc_middle::traits::solve::{
     CanonicalResponse, Certainty, ExternalConstraintsData, Goal, GoalSource, QueryResult, Response,

compiler/rustc_trait_selection/src/traits/engine.rs

@@ -19,6 +19,7 @@ use rustc_infer::infer::{DefineOpaqueTypes, InferCtxt, InferOk};
 use rustc_infer::traits::{
     FulfillmentError, Obligation, ObligationCause, PredicateObligation, TraitEngineExt as _,
 };
+use rustc_macros::extension;
 use rustc_middle::arena::ArenaAllocatable;
 use rustc_middle::traits::query::NoSolution;
 use rustc_middle::ty::error::TypeError;

compiler/rustc_trait_selection/src/traits/error_reporting/infer_ctxt_ext.rs

@@ -4,6 +4,7 @@ use crate::traits::{Obligation, ObligationCause, ObligationCtxt};
 use rustc_errors::{codes::*, pluralize, struct_span_code_err, Applicability, Diag};
 use rustc_hir as hir;
 use rustc_hir::Node;
+use rustc_macros::extension;
 use rustc_middle::ty::{self, Ty};
 use rustc_span::{Span, DUMMY_SP};
 

compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs

@@ -9,6 +9,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::{codes::*, struct_span_code_err, ErrorGuaranteed};
 use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LocalDefId};
+use rustc_macros::{extension, LintDiagnostic};
 use rustc_middle::ty::GenericArgsRef;
 use rustc_middle::ty::{self, GenericParamDefKind, TyCtxt};
 use rustc_parse_format::{ParseMode, Parser, Piece, Position};

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -26,6 +26,7 @@ use rustc_hir::{CoroutineDesugaring, CoroutineKind, CoroutineSource, Expr, HirId
 use rustc_infer::infer::error_reporting::TypeErrCtxt;
 use rustc_infer::infer::type_variable::TypeVariableOrigin;
 use rustc_infer::infer::{BoundRegionConversionTime, DefineOpaqueTypes, InferOk};
+use rustc_macros::extension;
 use rustc_middle::hir::map;
 use rustc_middle::traits::IsConstable;
 use rustc_middle::ty::error::TypeError::{self, Sorts};

compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs

@@ -32,6 +32,7 @@ use rustc_hir::intravisit::Visitor;
 use rustc_hir::{GenericParam, Item, Node};
 use rustc_infer::infer::error_reporting::TypeErrCtxt;
 use rustc_infer::infer::{InferOk, TypeTrace};
+use rustc_macros::extension;
 use rustc_middle::traits::select::OverflowError;
 use rustc_middle::traits::SignatureMismatchData;
 use rustc_middle::ty::abstract_const::NotConstEvaluatable;

compiler/rustc_trait_selection/src/traits/normalize.rs

@@ -8,6 +8,7 @@ use rustc_infer::infer::at::At;
 use rustc_infer::infer::InferOk;
 use rustc_infer::traits::PredicateObligation;
 use rustc_infer::traits::{FulfillmentError, Normalized, Obligation, TraitEngine};
+use rustc_macros::extension;
 use rustc_middle::traits::{ObligationCause, ObligationCauseCode, Reveal};
 use rustc_middle::ty::{self, Ty, TyCtxt, TypeFolder};
 use rustc_middle::ty::{TypeFoldable, TypeSuperFoldable, TypeVisitable, TypeVisitableExt};

compiler/rustc_trait_selection/src/traits/outlives_bounds.rs

@@ -3,6 +3,7 @@ use crate::traits::{ObligationCause, ObligationCtxt};
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_infer::infer::resolve::OpportunisticRegionResolver;
 use rustc_infer::infer::InferOk;
+use rustc_macros::extension;
 use rustc_middle::infer::canonical::{OriginalQueryValues, QueryRegionConstraints};
 use rustc_middle::ty::{self, ParamEnv, Ty, TypeFolder, TypeVisitableExt};
 use rustc_span::def_id::LocalDefId;

compiler/rustc_trait_selection/src/traits/query/evaluate_obligation.rs

@@ -1,4 +1,5 @@
 use rustc_infer::traits::{TraitEngine, TraitEngineExt};
+use rustc_macros::extension;
 
 use crate::infer::canonical::OriginalQueryValues;
 use crate::infer::InferCtxt;

compiler/rustc_trait_selection/src/traits/query/normalize.rs

@@ -13,6 +13,7 @@ use crate::traits::{ObligationCause, PredicateObligation, Reveal};
 use rustc_data_structures::sso::SsoHashMap;
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_infer::traits::Normalized;
+use rustc_macros::extension;
 use rustc_middle::ty::fold::{FallibleTypeFolder, TypeFoldable, TypeSuperFoldable};
 use rustc_middle::ty::visit::{TypeSuperVisitable, TypeVisitable, TypeVisitableExt};
 use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitor};