remove redundant imports

detects redundant imports that can be eliminated.

for #117772 :

In order to facilitate review and modification, split the checking code and
removing redundant imports code into two PR.

283 files changed, 140 insertions, 510 deletions

diff --git a/compiler/rustc_ast/src/mut_visit.rs b/compiler/rustc_ast/src/mut_visit.rs
index 41c4e024447..01defcff9ef 100644
--- a/compiler/rustc_ast/src/mut_visit.rs
+++ b/compiler/rustc_ast/src/mut_visit.rs
@@ -7,10 +7,10 @@
 //! a `MutVisitor` renaming item names in a module will miss all of those
 //! that are created by the expansion of a macro.
 
+use crate::ast::*;
 use crate::ptr::P;
 use crate::token::{self, Token};
 use crate::tokenstream::*;
-use crate::{ast::*, StaticItem};
 
 use rustc_data_structures::flat_map_in_place::FlatMapInPlace;
 use rustc_data_structures::stack::ensure_sufficient_stack;
diff --git a/compiler/rustc_ast/src/token.rs b/compiler/rustc_ast/src/token.rs
index a7c6f8c5d8c..b0cd2ec9815 100644
--- a/compiler/rustc_ast/src/token.rs
+++ b/compiler/rustc_ast/src/token.rs
@@ -13,7 +13,7 @@ use rustc_macros::HashStable_Generic;
 use rustc_span::symbol::{kw, sym};
 #[allow(hidden_glob_reexports)]
 use rustc_span::symbol::{Ident, Symbol};
-use rustc_span::{self, edition::Edition, Span, DUMMY_SP};
+use rustc_span::{edition::Edition, Span, DUMMY_SP};
 use std::borrow::Cow;
 use std::fmt;
 
diff --git a/compiler/rustc_ast/src/visit.rs b/compiler/rustc_ast/src/visit.rs
index ce5214efaca..27f1b84f372 100644
--- a/compiler/rustc_ast/src/visit.rs
+++ b/compiler/rustc_ast/src/visit.rs
@@ -13,7 +13,7 @@
 //! instance, a walker looking for item names in a module will miss all of
 //! those that are created by the expansion of a macro.
 
-use crate::{ast::*, StaticItem};
+use crate::ast::*;
 
 use rustc_span::symbol::Ident;
 use rustc_span::Span;
diff --git a/compiler/rustc_ast_lowering/src/expr.rs b/compiler/rustc_ast_lowering/src/expr.rs
index 99691f43f91..e9f88d50937 100644
--- a/compiler/rustc_ast_lowering/src/expr.rs
+++ b/compiler/rustc_ast_lowering/src/expr.rs
@@ -8,7 +8,6 @@ use super::errors::{
 use super::ResolverAstLoweringExt;
 use super::{ImplTraitContext, LoweringContext, ParamMode, ParenthesizedGenericArgs};
 use crate::{FnDeclKind, ImplTraitPosition};
-use rustc_ast::attr;
 use rustc_ast::ptr::P as AstP;
 use rustc_ast::*;
 use rustc_data_structures::stack::ensure_sufficient_stack;
diff --git a/compiler/rustc_ast_lowering/src/format.rs b/compiler/rustc_ast_lowering/src/format.rs
index 8fa2cae43bf..6a82005c448 100644
--- a/compiler/rustc_ast_lowering/src/format.rs
+++ b/compiler/rustc_ast_lowering/src/format.rs
@@ -1,6 +1,6 @@
 use super::LoweringContext;
 use rustc_ast as ast;
-use rustc_ast::visit::{self, Visitor};
+use rustc_ast::visit::Visitor;
 use rustc_ast::*;
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_hir as hir;
diff --git a/compiler/rustc_ast_lowering/src/index.rs b/compiler/rustc_ast_lowering/src/index.rs
index 1741611fb11..f042f46e59c 100644
--- a/compiler/rustc_ast_lowering/src/index.rs
+++ b/compiler/rustc_ast_lowering/src/index.rs
@@ -2,7 +2,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sorted_map::SortedMap;
 use rustc_hir as hir;
 use rustc_hir::def_id::LocalDefId;
-use rustc_hir::intravisit::{self, Visitor};
+use rustc_hir::intravisit::Visitor;
 use rustc_hir::*;
 use rustc_index::{Idx, IndexVec};
 use rustc_middle::span_bug;
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs
index b4c211eec69..a005a6e44ce 100644
--- a/compiler/rustc_ast_lowering/src/lib.rs
+++ b/compiler/rustc_ast_lowering/src/lib.rs
@@ -45,7 +45,6 @@ extern crate tracing;
 use crate::errors::{AssocTyParentheses, AssocTyParenthesesSub, MisplacedImplTrait};
 
 use rustc_ast::ptr::P;
-use rustc_ast::visit;
 use rustc_ast::{self as ast, *};
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::captures::Captures;
diff --git a/compiler/rustc_ast_passes/src/ast_validation.rs b/compiler/rustc_ast_passes/src/ast_validation.rs
index 1f9bc09f5f7..59cf18c2459 100644
--- a/compiler/rustc_ast_passes/src/ast_validation.rs
+++ b/compiler/rustc_ast_passes/src/ast_validation.rs
@@ -8,9 +8,9 @@
 
 use itertools::{Either, Itertools};
 use rustc_ast::ptr::P;
-use rustc_ast::visit::{self, AssocCtxt, BoundKind, FnCtxt, FnKind, Visitor};
+use rustc_ast::visit::{AssocCtxt, BoundKind, FnCtxt, FnKind, Visitor};
+use rustc_ast::walk_list;
 use rustc_ast::*;
-use rustc_ast::{walk_list, StaticItem};
 use rustc_ast_pretty::pprust::{self, State};
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_feature::Features;
diff --git a/compiler/rustc_borrowck/src/dataflow.rs b/compiler/rustc_borrowck/src/dataflow.rs
index 1b544b53012..1bd891bdd68 100644
--- a/compiler/rustc_borrowck/src/dataflow.rs
+++ b/compiler/rustc_borrowck/src/dataflow.rs
@@ -10,7 +10,7 @@ use rustc_middle::ty::RegionVid;
 use rustc_middle::ty::TyCtxt;
 use rustc_mir_dataflow::impls::{EverInitializedPlaces, MaybeUninitializedPlaces};
 use rustc_mir_dataflow::ResultsVisitable;
-use rustc_mir_dataflow::{self, fmt::DebugWithContext, GenKill};
+use rustc_mir_dataflow::{fmt::DebugWithContext, GenKill};
 use rustc_mir_dataflow::{Analysis, AnalysisDomain, Results};
 use std::fmt;
 
diff --git a/compiler/rustc_borrowck/src/region_infer/graphviz.rs b/compiler/rustc_borrowck/src/region_infer/graphviz.rs
index a0cf22e935a..408c8390e76 100644
--- a/compiler/rustc_borrowck/src/region_infer/graphviz.rs
+++ b/compiler/rustc_borrowck/src/region_infer/graphviz.rs
@@ -8,7 +8,6 @@ use std::borrow::Cow;
 use std::io::{self, Write};
 
 use super::*;
-use crate::constraints::OutlivesConstraint;
 use rustc_graphviz as dot;
 
 impl<'tcx> RegionInferenceContext<'tcx> {
diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs
index ecc9905e33e..e782221a4c2 100644
--- a/compiler/rustc_borrowck/src/type_check/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/mod.rs
@@ -24,7 +24,6 @@ use rustc_infer::infer::{
 };
 use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::visit::{NonMutatingUseContext, PlaceContext, Visitor};
-use rustc_middle::mir::AssertKind;
 use rustc_middle::mir::*;
 use rustc_middle::traits::query::NoSolution;
 use rustc_middle::traits::ObligationCause;
diff --git a/compiler/rustc_builtin_macros/src/source_util.rs b/compiler/rustc_builtin_macros/src/source_util.rs
index 7ae4b1b59dc..37808854a56 100644
--- a/compiler/rustc_builtin_macros/src/source_util.rs
+++ b/compiler/rustc_builtin_macros/src/source_util.rs
@@ -5,11 +5,11 @@ use rustc_ast::tokenstream::TokenStream;
 use rustc_ast_pretty::pprust;
 use rustc_expand::base::{self, *};
 use rustc_expand::module::DirOwnership;
+use rustc_parse::new_parser_from_file;
 use rustc_parse::parser::{ForceCollect, Parser};
-use rustc_parse::{self, new_parser_from_file};
 use rustc_session::lint::builtin::INCOMPLETE_INCLUDE;
 use rustc_span::symbol::Symbol;
-use rustc_span::{self, Pos, Span};
+use rustc_span::{Pos, Span};
 
 use smallvec::SmallVec;
 use std::rc::Rc;
diff --git a/compiler/rustc_builtin_macros/src/test_harness.rs b/compiler/rustc_builtin_macros/src/test_harness.rs
index 380556c3ca5..c5daf17abb9 100644
--- a/compiler/rustc_builtin_macros/src/test_harness.rs
+++ b/compiler/rustc_builtin_macros/src/test_harness.rs
@@ -2,7 +2,7 @@
 
 use rustc_ast as ast;
 use rustc_ast::entry::EntryPointType;
-use rustc_ast::mut_visit::{ExpectOne, *};
+use rustc_ast::mut_visit::*;
 use rustc_ast::ptr::P;
 use rustc_ast::visit::{walk_item, Visitor};
 use rustc_ast::{attr, ModKind};
diff --git a/compiler/rustc_codegen_cranelift/src/abi/comments.rs b/compiler/rustc_codegen_cranelift/src/abi/comments.rs
index ade6968de2b..a318cae1722 100644
--- a/compiler/rustc_codegen_cranelift/src/abi/comments.rs
+++ b/compiler/rustc_codegen_cranelift/src/abi/comments.rs
@@ -3,7 +3,6 @@
 
 use std::borrow::Cow;
 
-use rustc_middle::mir;
 use rustc_target::abi::call::PassMode;
 
 use crate::prelude::*;
diff --git a/compiler/rustc_codegen_cranelift/src/abi/mod.rs b/compiler/rustc_codegen_cranelift/src/abi/mod.rs
index 0ff1473da43..2c194f6d6d3 100644
--- a/compiler/rustc_codegen_cranelift/src/abi/mod.rs
+++ b/compiler/rustc_codegen_cranelift/src/abi/mod.rs
@@ -6,7 +6,7 @@ mod returning;
 
 use std::borrow::Cow;
 
-use cranelift_codegen::ir::{AbiParam, SigRef};
+use cranelift_codegen::ir::SigRef;
 use cranelift_module::ModuleError;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::ty::layout::FnAbiOf;
diff --git a/compiler/rustc_codegen_cranelift/src/analyze.rs b/compiler/rustc_codegen_cranelift/src/analyze.rs
index 321612238ea..c5762638a6b 100644
--- a/compiler/rustc_codegen_cranelift/src/analyze.rs
+++ b/compiler/rustc_codegen_cranelift/src/analyze.rs
@@ -2,7 +2,6 @@
 
 use rustc_index::IndexVec;
 use rustc_middle::mir::StatementKind::*;
-use rustc_middle::ty::Ty;
 
 use crate::prelude::*;
 
diff --git a/compiler/rustc_codegen_cranelift/src/constant.rs b/compiler/rustc_codegen_cranelift/src/constant.rs
index 65f7ee6999a..9ffa006e59b 100644
--- a/compiler/rustc_codegen_cranelift/src/constant.rs
+++ b/compiler/rustc_codegen_cranelift/src/constant.rs
@@ -3,10 +3,9 @@
 use std::cmp::Ordering;
 
 use cranelift_module::*;
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::fx::FxHashSet;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::mir::interpret::{read_target_uint, AllocId, GlobalAlloc, Scalar};
-use rustc_middle::mir::ConstValue;
 use rustc_middle::ty::ScalarInt;
 
 use crate::prelude::*;
diff --git a/compiler/rustc_codegen_cranelift/src/inline_asm.rs b/compiler/rustc_codegen_cranelift/src/inline_asm.rs
index 25d14319f57..73f4bc7c151 100644
--- a/compiler/rustc_codegen_cranelift/src/inline_asm.rs
+++ b/compiler/rustc_codegen_cranelift/src/inline_asm.rs
@@ -3,7 +3,6 @@
 use std::fmt::Write;
 
 use rustc_ast::ast::{InlineAsmOptions, InlineAsmTemplatePiece};
-use rustc_middle::mir::InlineAsmOperand;
 use rustc_span::sym;
 use rustc_target::asm::*;
 use target_lexicon::BinaryFormat;
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm.rs
index 659e6c133ef..dbd5db87511 100644
--- a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm.rs
+++ b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm.rs
@@ -1,7 +1,5 @@
 //! Emulate LLVM intrinsics
 
-use rustc_middle::ty::GenericArgsRef;
-
 use crate::intrinsics::*;
 use crate::prelude::*;
 
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_aarch64.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_aarch64.rs
index ee098be1fce..e1e514dca44 100644
--- a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_aarch64.rs
+++ b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_aarch64.rs
@@ -1,7 +1,5 @@
 //! Emulate AArch64 LLVM intrinsics
 
-use rustc_middle::ty::GenericArgsRef;
-
 use crate::intrinsics::*;
 use crate::prelude::*;
 
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_x86.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_x86.rs
index 07b95b7933d..99bb5c4eae2 100644
--- a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_x86.rs
+++ b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_x86.rs
@@ -1,7 +1,6 @@
 //! Emulate x86 LLVM intrinsics
 
 use rustc_ast::ast::{InlineAsmOptions, InlineAsmTemplatePiece};
-use rustc_middle::ty::GenericArgsRef;
 use rustc_target::asm::*;
 
 use crate::inline_asm::{codegen_inline_asm_inner, CInlineAsmOperand};
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/simd.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/simd.rs
index 5997e6026b4..fe4f073f799 100644
--- a/compiler/rustc_codegen_cranelift/src/intrinsics/simd.rs
+++ b/compiler/rustc_codegen_cranelift/src/intrinsics/simd.rs
@@ -1,8 +1,6 @@
 //! Codegen `extern "platform-intrinsic"` intrinsics.
 
 use cranelift_codegen::ir::immediates::Offset32;
-use rustc_middle::ty::GenericArgsRef;
-use rustc_span::Symbol;
 use rustc_target::abi::Endian;
 
 use super::*;
diff --git a/compiler/rustc_codegen_llvm/src/abi.rs b/compiler/rustc_codegen_llvm/src/abi.rs
index b5f53f51838..97dc401251c 100644
--- a/compiler/rustc_codegen_llvm/src/abi.rs
+++ b/compiler/rustc_codegen_llvm/src/abi.rs
@@ -15,7 +15,6 @@ use rustc_middle::ty::layout::LayoutOf;
 pub use rustc_middle::ty::layout::{FAT_PTR_ADDR, FAT_PTR_EXTRA};
 use rustc_middle::ty::Ty;
 use rustc_session::config;
-use rustc_target::abi::call::ArgAbi;
 pub use rustc_target::abi::call::*;
 use rustc_target::abi::{self, HasDataLayout, Int};
 pub use rustc_target::spec::abi::Abi;
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
index cf78fc56b49..98563673c30 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
@@ -35,7 +35,7 @@ use rustc_middle::ty::{
 use rustc_session::config::{self, DebugInfo, Lto};
 use rustc_span::symbol::Symbol;
 use rustc_span::FileName;
-use rustc_span::{self, FileNameDisplayPreference, SourceFile};
+use rustc_span::{FileNameDisplayPreference, SourceFile};
 use rustc_symbol_mangling::typeid_for_trait_ref;
 use rustc_target::abi::{Align, Size};
 use smallvec::smallvec;
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
index 4832b147a54..a0ae1e9bf5d 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
@@ -32,7 +32,7 @@ use rustc_middle::ty::{self, Instance, ParamEnv, Ty, TypeVisitableExt};
 use rustc_session::config::{self, DebugInfo};
 use rustc_session::Session;
 use rustc_span::symbol::Symbol;
-use rustc_span::{self, BytePos, Pos, SourceFile, SourceFileAndLine, SourceFileHash, Span};
+use rustc_span::{BytePos, Pos, SourceFile, SourceFileAndLine, SourceFileHash, Span};
 use rustc_target::abi::Size;
 
 use libc::c_uint;
diff --git a/compiler/rustc_codegen_ssa/src/mir/statement.rs b/compiler/rustc_codegen_ssa/src/mir/statement.rs
index 899e41265bb..a158fc6e260 100644
--- a/compiler/rustc_codegen_ssa/src/mir/statement.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/statement.rs
@@ -3,7 +3,6 @@ use rustc_middle::mir::NonDivergingIntrinsic;
 
 use super::FunctionCx;
 use super::LocalRef;
-use crate::traits::BuilderMethods;
 use crate::traits::*;
 
 impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
diff --git a/compiler/rustc_const_eval/src/transform/check_consts/check.rs b/compiler/rustc_const_eval/src/transform/check_consts/check.rs
index e604f4c1aec..5380d3071d6 100644
--- a/compiler/rustc_const_eval/src/transform/check_consts/check.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/check.rs
@@ -12,7 +12,7 @@ use rustc_middle::traits::BuiltinImplSource;
 use rustc_middle::ty::GenericArgs;
 use rustc_middle::ty::{self, adjustment::PointerCoercion, Instance, InstanceDef, Ty, TyCtxt};
 use rustc_middle::ty::{TraitRef, TypeVisitableExt};
-use rustc_mir_dataflow::{self, Analysis};
+use rustc_mir_dataflow::Analysis;
 use rustc_span::{sym, Span, Symbol};
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
 use rustc_trait_selection::traits::{self, ObligationCauseCode, ObligationCtxt, SelectionContext};
diff --git a/compiler/rustc_data_structures/src/fingerprint/tests.rs b/compiler/rustc_data_structures/src/fingerprint/tests.rs
index 09ec2622a65..e04af19abf2 100644
--- a/compiler/rustc_data_structures/src/fingerprint/tests.rs
+++ b/compiler/rustc_data_structures/src/fingerprint/tests.rs
@@ -1,5 +1,4 @@
 use super::*;
-use crate::stable_hasher::Hash64;
 
 // Check that `combine_commutative` is order independent.
 #[test]
diff --git a/compiler/rustc_data_structures/src/graph/implementation/tests.rs b/compiler/rustc_data_structures/src/graph/implementation/tests.rs
index dc1ce1747bf..3ae5f5868f0 100644
--- a/compiler/rustc_data_structures/src/graph/implementation/tests.rs
+++ b/compiler/rustc_data_structures/src/graph/implementation/tests.rs
@@ -1,5 +1,4 @@
 use crate::graph::implementation::*;
-use std::fmt::Debug;
 
 type TestGraph = Graph<&'static str, &'static str>;
 
diff --git a/compiler/rustc_data_structures/src/intern/tests.rs b/compiler/rustc_data_structures/src/intern/tests.rs
index 09810a0850e..a85cd480a09 100644
--- a/compiler/rustc_data_structures/src/intern/tests.rs
+++ b/compiler/rustc_data_structures/src/intern/tests.rs
@@ -1,5 +1,4 @@
 use super::*;
-use std::cmp::Ordering;
 
 #[derive(Debug)]
 struct S(u32);
diff --git a/compiler/rustc_data_structures/src/obligation_forest/tests.rs b/compiler/rustc_data_structures/src/obligation_forest/tests.rs
index bc252f772a1..d09c8e54436 100644
--- a/compiler/rustc_data_structures/src/obligation_forest/tests.rs
+++ b/compiler/rustc_data_structures/src/obligation_forest/tests.rs
@@ -1,7 +1,6 @@
 use super::*;
 
 use std::fmt;
-use std::marker::PhantomData;
 
 impl<'a> super::ForestObligation for &'a str {
     type CacheKey = &'a str;
diff --git a/compiler/rustc_data_structures/src/sip128/tests.rs b/compiler/rustc_data_structures/src/sip128/tests.rs
index cc6d3b0f471..e9dd0f1176b 100644
--- a/compiler/rustc_data_structures/src/sip128/tests.rs
+++ b/compiler/rustc_data_structures/src/sip128/tests.rs
@@ -1,6 +1,6 @@
 use super::*;
 
-use std::hash::{Hash, Hasher};
+use std::hash::Hash;
 
 // Hash just the bytes of the slice, without length prefix
 struct Bytes<'a>(&'a [u8]);
diff --git a/compiler/rustc_errors/src/json/tests.rs b/compiler/rustc_errors/src/json/tests.rs
index 1f9a2981e02..5f9e821a48c 100644
--- a/compiler/rustc_errors/src/json/tests.rs
+++ b/compiler/rustc_errors/src/json/tests.rs
@@ -1,11 +1,8 @@
 use super::*;
 
-use crate::json::JsonEmitter;
-use rustc_span::source_map::{FilePathMapping, SourceMap};
-
-use crate::emitter::{ColorConfig, HumanReadableErrorType};
-use crate::{Handler, TerminalUrl};
-use rustc_span::{BytePos, Span};
+use crate::emitter::ColorConfig;
+use crate::Handler;
+use rustc_span::BytePos;
 
 use std::str;
 
diff --git a/compiler/rustc_errors/src/markdown/tests/term.rs b/compiler/rustc_errors/src/markdown/tests/term.rs
index 6f68fb25a58..a0d956bf0cd 100644
--- a/compiler/rustc_errors/src/markdown/tests/term.rs
+++ b/compiler/rustc_errors/src/markdown/tests/term.rs
@@ -3,7 +3,6 @@ use std::path::PathBuf;
 use termcolor::{BufferWriter, ColorChoice};
 
 use super::*;
-use crate::markdown::MdStream;
 
 const INPUT: &str = include_str!("input.md");
 const OUTPUT_PATH: &[&str] = &[env!("CARGO_MANIFEST_DIR"), "src","markdown","tests","output.stdout"];
diff --git a/compiler/rustc_expand/src/base.rs b/compiler/rustc_expand/src/base.rs
index 74f46efb365..11db4bb4017 100644
--- a/compiler/rustc_expand/src/base.rs
+++ b/compiler/rustc_expand/src/base.rs
@@ -21,7 +21,7 @@ use rustc_errors::{
 use rustc_feature::Features;
 use rustc_lint_defs::builtin::PROC_MACRO_BACK_COMPAT;
 use rustc_lint_defs::{BufferedEarlyLint, BuiltinLintDiagnostics, RegisteredTools};
-use rustc_parse::{self, parser, MACRO_ARGUMENTS};
+use rustc_parse::{parser, MACRO_ARGUMENTS};
 use rustc_session::errors::report_lit_error;
 use rustc_session::{parse::ParseSess, Limit, Session};
 use rustc_span::def_id::{CrateNum, DefId, LocalDefId};
diff --git a/compiler/rustc_hir_analysis/src/check/check.rs b/compiler/rustc_hir_analysis/src/check/check.rs
index 56e272b14bd..ec589e2dbbc 100644
--- a/compiler/rustc_hir_analysis/src/check/check.rs
+++ b/compiler/rustc_hir_analysis/src/check/check.rs
@@ -1,5 +1,5 @@
 use crate::check::intrinsicck::InlineAsmCtxt;
-use crate::errors::{self, LinkageType};
+use crate::errors::LinkageType;
 
 use super::compare_impl_item::check_type_bounds;
 use super::compare_impl_item::{compare_impl_method, compare_impl_ty};
@@ -8,9 +8,8 @@ use rustc_attr as attr;
 use rustc_errors::{ErrorGuaranteed, MultiSpan};
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind};
-use rustc_hir::def_id::{DefId, LocalDefId, LocalModDefId};
+use rustc_hir::def_id::LocalModDefId;
 use rustc_hir::Node;
-use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{RegionVariableOrigin, TyCtxtInferExt};
 use rustc_infer::traits::{Obligation, TraitEngineExt as _};
 use rustc_lint_defs::builtin::REPR_TRANSPARENT_EXTERNAL_PRIVATE_FIELDS;
@@ -21,18 +20,15 @@ use rustc_middle::ty::layout::{LayoutError, MAX_SIMD_LANES};
 use rustc_middle::ty::util::{Discr, IntTypeExt};
 use rustc_middle::ty::GenericArgKind;
 use rustc_middle::ty::{
-    self, AdtDef, ParamEnv, RegionKind, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable,
-    TypeVisitableExt,
+    AdtDef, ParamEnv, RegionKind, TypeSuperVisitable, TypeVisitable, TypeVisitableExt,
 };
 use rustc_session::lint::builtin::{UNINHABITED_STATIC, UNSUPPORTED_CALLING_CONVENTIONS};
 use rustc_span::symbol::sym;
-use rustc_span::{self, Span};
 use rustc_target::abi::FieldIdx;
-use rustc_target::spec::abi::Abi;
 use rustc_trait_selection::traits::error_reporting::on_unimplemented::OnUnimplementedDirective;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
 use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _;
-use rustc_trait_selection::traits::{self, ObligationCtxt, TraitEngine, TraitEngineExt as _};
+use rustc_trait_selection::traits::{self, TraitEngine, TraitEngineExt as _};
 use rustc_type_ir::fold::TypeFoldable;
 
 use std::ops::ControlFlow;
diff --git a/compiler/rustc_hir_pretty/src/lib.rs b/compiler/rustc_hir_pretty/src/lib.rs
index 1c4534287eb..8701626058d 100644
--- a/compiler/rustc_hir_pretty/src/lib.rs
+++ b/compiler/rustc_hir_pretty/src/lib.rs
@@ -16,7 +16,7 @@ use rustc_hir::{BindingAnnotation, ByRef, GenericArg, GenericParam, GenericParam
 use rustc_hir::{GenericBound, PatKind, RangeEnd, TraitBoundModifier};
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::{kw, Ident, Symbol};
-use rustc_span::{self, FileName};
+use rustc_span::FileName;
 use rustc_target::spec::abi::Abi;
 
 use std::cell::Cell;
diff --git a/compiler/rustc_hir_typeck/src/coercion.rs b/compiler/rustc_hir_typeck/src/coercion.rs
index 7f56b3850dd..0d3bb0f7e0c 100644
--- a/compiler/rustc_hir_typeck/src/coercion.rs
+++ b/compiler/rustc_hir_typeck/src/coercion.rs
@@ -58,7 +58,7 @@ use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt, TypeAndMut};
 use rustc_session::parse::feature_err;
 use rustc_span::symbol::sym;
-use rustc_span::{self, DesugaringKind};
+use rustc_span::DesugaringKind;
 use rustc_target::spec::abi::Abi;
 use rustc_trait_selection::infer::InferCtxtExt as _;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
diff --git a/compiler/rustc_hir_typeck/src/diverges.rs b/compiler/rustc_hir_typeck/src/diverges.rs
index 29fcc61cbb5..0b559a0858e 100644
--- a/compiler/rustc_hir_typeck/src/diverges.rs
+++ b/compiler/rustc_hir_typeck/src/diverges.rs
@@ -1,4 +1,4 @@
-use rustc_span::{self, Span, DUMMY_SP};
+use rustc_span::{Span, DUMMY_SP};
 use std::{cmp, ops};
 
 /// Tracks whether executing a node may exit normally (versus
diff --git a/compiler/rustc_hir_typeck/src/expectation.rs b/compiler/rustc_hir_typeck/src/expectation.rs
index 35e5fb769a5..ff84e753d70 100644
--- a/compiler/rustc_hir_typeck/src/expectation.rs
+++ b/compiler/rustc_hir_typeck/src/expectation.rs
@@ -1,6 +1,6 @@
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use rustc_middle::ty::{self, Ty};
-use rustc_span::{self, Span};
+use rustc_span::Span;
 
 use super::Expectation::*;
 use super::FnCtxt;
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/adjust_fulfillment_errors.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/adjust_fulfillment_errors.rs
index e3aca11fd03..9b5459529ff 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/adjust_fulfillment_errors.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/adjust_fulfillment_errors.rs
@@ -4,7 +4,7 @@ use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::DefId;
 use rustc_infer::{infer::type_variable::TypeVariableOriginKind, traits::ObligationCauseCode};
 use rustc_middle::ty::{self, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitor};
-use rustc_span::{self, symbol::kw, Span};
+use rustc_span::{symbol::kw, Span};
 use rustc_trait_selection::traits;
 
 use std::ops::ControlFlow;
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
index 509596c1e90..bb9b849f03b 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
@@ -33,7 +33,7 @@ use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{self, IsSuggestable, Ty, TyCtxt};
 use rustc_session::Session;
 use rustc_span::symbol::{kw, Ident};
-use rustc_span::{self, sym, BytePos, Span};
+use rustc_span::{sym, BytePos, Span};
 use rustc_trait_selection::traits::{self, ObligationCauseCode, SelectionContext};
 
 use std::iter;
diff --git a/compiler/rustc_hir_typeck/src/inherited.rs b/compiler/rustc_hir_typeck/src/inherited.rs
index 281074a8519..7a6a2b2a010 100644
--- a/compiler/rustc_hir_typeck/src/inherited.rs
+++ b/compiler/rustc_hir_typeck/src/inherited.rs
@@ -9,7 +9,7 @@ use rustc_middle::traits::DefiningAnchor;
 use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_span::def_id::LocalDefIdMap;
-use rustc_span::{self, Span};
+use rustc_span::Span;
 use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt;
 use rustc_trait_selection::traits::{self, PredicateObligation, TraitEngine, TraitEngineExt as _};
 
diff --git a/compiler/rustc_hir_typeck/src/op.rs b/compiler/rustc_hir_typeck/src/op.rs
index 1e9387ef041..59b4b0032f8 100644
--- a/compiler/rustc_hir_typeck/src/op.rs
+++ b/compiler/rustc_hir_typeck/src/op.rs
@@ -4,7 +4,7 @@ use super::method::MethodCallee;
 use super::{has_expected_num_generic_args, FnCtxt};
 use crate::Expectation;
 use rustc_ast as ast;
-use rustc_errors::{self, struct_span_err, Applicability, Diagnostic, DiagnosticBuilder};
+use rustc_errors::{struct_span_err, Applicability, Diagnostic, DiagnosticBuilder};
 use rustc_hir as hir;
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use rustc_infer::traits::ObligationCauseCode;
diff --git a/compiler/rustc_incremental/src/persist/dirty_clean.rs b/compiler/rustc_incremental/src/persist/dirty_clean.rs
index eaf83b7ee5f..0f2194139df 100644
--- a/compiler/rustc_incremental/src/persist/dirty_clean.rs
+++ b/compiler/rustc_incremental/src/persist/dirty_clean.rs
@@ -32,7 +32,6 @@ use rustc_middle::hir::nested_filter;
 use rustc_middle::ty::TyCtxt;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
-use std::iter::FromIterator;
 use thin_vec::ThinVec;
 
 const LOADED_FROM_DISK: Symbol = sym::loaded_from_disk;
diff --git a/compiler/rustc_infer/src/errors/note_and_explain.rs b/compiler/rustc_infer/src/errors/note_and_explain.rs
index 3ee4710bdef..68bf36a1615 100644
--- a/compiler/rustc_infer/src/errors/note_and_explain.rs
+++ b/compiler/rustc_infer/src/errors/note_and_explain.rs
@@ -1,6 +1,6 @@
 use crate::fluent_generated as fluent;
 use crate::infer::error_reporting::nice_region_error::find_anon_type;
-use rustc_errors::{self, AddToDiagnostic, Diagnostic, IntoDiagnosticArg, SubdiagnosticMessage};
+use rustc_errors::{AddToDiagnostic, Diagnostic, IntoDiagnosticArg, SubdiagnosticMessage};
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_span::{symbol::kw, Span};
 
diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs
index 09d92c2dfc0..9b59ead0463 100644
--- a/compiler/rustc_interface/src/passes.rs
+++ b/compiler/rustc_interface/src/passes.rs
@@ -22,7 +22,7 @@ use rustc_middle::ty::{self, GlobalCtxt, RegisteredTools, TyCtxt};
 use rustc_middle::util::Providers;
 use rustc_mir_build as mir_build;
 use rustc_parse::{parse_crate_from_file, parse_crate_from_source_str, validate_attr};
-use rustc_passes::{self, abi_test, hir_stats, layout_test};
+use rustc_passes::{abi_test, hir_stats, layout_test};
 use rustc_resolve::Resolver;
 use rustc_session::code_stats::VTableSizeInfo;
 use rustc_session::config::{CrateType, Input, OutFileName, OutputFilenames, OutputType};
diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs
index 64de5e92abf..930e29f2389 100644
--- a/compiler/rustc_lint/src/builtin.rs
+++ b/compiler/rustc_lint/src/builtin.rs
@@ -40,7 +40,6 @@ use crate::{
     },
     EarlyContext, EarlyLintPass, LateContext, LateLintPass, Level, LintContext,
 };
-use rustc_ast::attr;
 use rustc_ast::tokenstream::{TokenStream, TokenTree};
 use rustc_ast::visit::{FnCtxt, FnKind};
 use rustc_ast::{self as ast, *};
diff --git a/compiler/rustc_lint/src/lib.rs b/compiler/rustc_lint/src/lib.rs
index 8e95a71e11f..83414ee702f 100644
--- a/compiler/rustc_lint/src/lib.rs
+++ b/compiler/rustc_lint/src/lib.rs
@@ -94,9 +94,6 @@ pub use array_into_iter::ARRAY_INTO_ITER;
 use rustc_hir::def_id::LocalModDefId;
 use rustc_middle::query::Providers;
 use rustc_middle::ty::TyCtxt;
-use rustc_session::lint::builtin::{
-    BARE_TRAIT_OBJECTS, ELIDED_LIFETIMES_IN_PATHS, EXPLICIT_OUTLIVES_REQUIREMENTS,
-};
 
 use array_into_iter::ArrayIntoIter;
 use async_fn_in_trait::AsyncFnInTrait;
diff --git a/compiler/rustc_macros/src/hash_stable.rs b/compiler/rustc_macros/src/hash_stable.rs
index 2893937fc4a..a6396ba687d 100644
--- a/compiler/rustc_macros/src/hash_stable.rs
+++ b/compiler/rustc_macros/src/hash_stable.rs
@@ -1,6 +1,6 @@
-use proc_macro2::{self, Ident};
+use proc_macro2::Ident;
 use quote::quote;
-use syn::{self, parse_quote};
+use syn::parse_quote;
 
 struct Attributes {
     ignore: bool,
diff --git a/compiler/rustc_macros/src/lift.rs b/compiler/rustc_macros/src/lift.rs
index ad7ac740417..3dedd88fb19 100644
--- a/compiler/rustc_macros/src/lift.rs
+++ b/compiler/rustc_macros/src/lift.rs
@@ -1,5 +1,5 @@
 use quote::quote;
-use syn::{self, parse_quote};
+use syn::parse_quote;
 
 pub fn lift_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream {
     s.add_bounds(synstructure::AddBounds::Generics);
diff --git a/compiler/rustc_metadata/src/rmeta/decoder.rs b/compiler/rustc_metadata/src/rmeta/decoder.rs
index 5725a759fef..89d10fea729 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder.rs
@@ -1,44 +1,34 @@
 // Decoding metadata from a single crate's metadata
 
-use crate::creader::{CStore, CrateMetadataRef};
+use crate::creader::CStore;
 use crate::rmeta::table::IsDefault;
 use crate::rmeta::*;
 
 use rustc_ast as ast;
 use rustc_data_structures::captures::Captures;
-use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::owned_slice::OwnedSlice;
-use rustc_data_structures::svh::Svh;
 use rustc_data_structures::sync::{AppendOnlyVec, AtomicBool, Lock, Lrc, OnceLock};
 use rustc_data_structures::unhash::UnhashMap;
 use rustc_expand::base::{SyntaxExtension, SyntaxExtensionKind};
 use rustc_expand::proc_macro::{AttrProcMacro, BangProcMacro, DeriveProcMacro};
-use rustc_hir::def::{CtorKind, DefKind, DocLinkResMap, Res};
-use rustc_hir::def_id::{CrateNum, DefId, DefIndex, CRATE_DEF_INDEX, LOCAL_CRATE};
-use rustc_hir::definitions::{DefKey, DefPath, DefPathData, DefPathHash};
+use rustc_hir::def::Res;
+use rustc_hir::def_id::{CRATE_DEF_INDEX, LOCAL_CRATE};
+use rustc_hir::definitions::{DefPath, DefPathData};
 use rustc_hir::diagnostic_items::DiagnosticItems;
-use rustc_index::{Idx, IndexVec};
-use rustc_middle::metadata::ModChild;
-use rustc_middle::middle::debugger_visualizer::DebuggerVisualizerFile;
-use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportInfo};
+use rustc_index::Idx;
 use rustc_middle::middle::lib_features::LibFeatures;
 use rustc_middle::mir::interpret::{AllocDecodingSession, AllocDecodingState};
 use rustc_middle::ty::codec::TyDecoder;
-use rustc_middle::ty::fast_reject::SimplifiedType;
-use rustc_middle::ty::{self, ParameterizedOverTcx, Ty, TyCtxt, Visibility};
+use rustc_middle::ty::Visibility;
 use rustc_serialize::opaque::MemDecoder;
 use rustc_serialize::{Decodable, Decoder};
-use rustc_session::cstore::{
-    CrateSource, ExternCrate, ForeignModule, LinkagePreference, NativeLib,
-};
+use rustc_session::cstore::{CrateSource, ExternCrate};
 use rustc_session::Session;
-use rustc_span::hygiene::ExpnIndex;
-use rustc_span::symbol::{kw, Ident, Symbol};
-use rustc_span::{self, BytePos, ExpnId, Pos, Span, SpanData, SyntaxContext, DUMMY_SP};
+use rustc_span::symbol::kw;
+use rustc_span::{BytePos, Pos, SpanData, SyntaxContext, DUMMY_SP};
 
 use proc_macro::bridge::client::ProcMacro;
 use std::iter::TrustedLen;
-use std::num::NonZeroUsize;
 use std::path::Path;
 use std::sync::atomic::Ordering;
 use std::{io, iter, mem};
diff --git a/compiler/rustc_metadata/src/rmeta/encoder.rs b/compiler/rustc_metadata/src/rmeta/encoder.rs
index ffb2375a734..ab18b6412b8 100644
--- a/compiler/rustc_metadata/src/rmeta/encoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/encoder.rs
@@ -1,51 +1,37 @@
 use crate::errors::{FailCreateFileEncoder, FailWriteFile};
-use crate::rmeta::def_path_hash_map::DefPathHashMapRef;
-use crate::rmeta::table::TableBuilder;
 use crate::rmeta::*;
 
-use rustc_ast::expand::StrippedCfgItem;
 use rustc_ast::Attribute;
 use rustc_data_structures::fingerprint::Fingerprint;
-use rustc_data_structures::fx::{FxHashMap, FxIndexSet};
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_data_structures::memmap::{Mmap, MmapMut};
 use rustc_data_structures::stable_hasher::{Hash128, HashStable, StableHasher};
 use rustc_data_structures::sync::{join, par_for_each_in, Lrc};
 use rustc_data_structures::temp_dir::MaybeTempDir;
 use rustc_hir as hir;
-use rustc_hir::def::DefKind;
-use rustc_hir::def_id::{
-    CrateNum, DefId, DefIndex, LocalDefId, LocalDefIdSet, CRATE_DEF_ID, CRATE_DEF_INDEX,
-    LOCAL_CRATE,
-};
+use rustc_hir::def_id::{LocalDefId, LocalDefIdSet, CRATE_DEF_ID, CRATE_DEF_INDEX, LOCAL_CRATE};
 use rustc_hir::definitions::DefPathData;
-use rustc_hir::lang_items::LangItem;
 use rustc_hir_pretty::id_to_string;
-use rustc_middle::middle::debugger_visualizer::DebuggerVisualizerFile;
 use rustc_middle::middle::dependency_format::Linkage;
-use rustc_middle::middle::exported_symbols::{
-    metadata_symbol_name, ExportedSymbol, SymbolExportInfo,
-};
-use rustc_middle::middle::lib_features::FeatureStability;
+use rustc_middle::middle::exported_symbols::metadata_symbol_name;
 use rustc_middle::mir::interpret;
 use rustc_middle::query::LocalCrate;
 use rustc_middle::query::Providers;
 use rustc_middle::traits::specialization_graph;
 use rustc_middle::ty::codec::TyEncoder;
-use rustc_middle::ty::fast_reject::{self, SimplifiedType, TreatParams};
-use rustc_middle::ty::{self, AssocItemContainer, SymbolName, Ty, TyCtxt};
+use rustc_middle::ty::fast_reject::{self, TreatParams};
+use rustc_middle::ty::{AssocItemContainer, SymbolName};
 use rustc_middle::util::common::to_readable_str;
 use rustc_serialize::{opaque, Decodable, Decoder, Encodable, Encoder};
 use rustc_session::config::{CrateType, OptLevel};
-use rustc_session::cstore::{ForeignModule, LinkagePreference, NativeLib};
-use rustc_span::hygiene::{ExpnIndex, HygieneEncodeContext, MacroKind};
-use rustc_span::symbol::{sym, Symbol};
-use rustc_span::{self, ExternalSource, FileName, SourceFile, Span, SpanData, SyntaxContext};
+use rustc_span::hygiene::HygieneEncodeContext;
+use rustc_span::symbol::sym;
+use rustc_span::{ExternalSource, FileName, SourceFile, SpanData, SyntaxContext};
 use std::borrow::Borrow;
 use std::collections::hash_map::Entry;
 use std::fs::File;
 use std::hash::Hash;
 use std::io::{Read, Seek, Write};
-use std::num::NonZeroUsize;
 use std::path::{Path, PathBuf};
 
 pub(super) struct EncodeContext<'a, 'tcx> {
diff --git a/compiler/rustc_metadata/src/rmeta/table.rs b/compiler/rustc_metadata/src/rmeta/table.rs
index 7cdbcd9193c..3fc6d9db331 100644
--- a/compiler/rustc_metadata/src/rmeta/table.rs
+++ b/compiler/rustc_metadata/src/rmeta/table.rs
@@ -1,13 +1,8 @@
 use crate::rmeta::*;
 
 use rustc_data_structures::fingerprint::Fingerprint;
-use rustc_hir::def::{CtorKind, CtorOf};
+use rustc_hir::def::CtorOf;
 use rustc_index::Idx;
-use rustc_middle::ty::{ParameterizedOverTcx, UnusedGenericParams};
-use rustc_serialize::opaque::FileEncoder;
-use rustc_span::hygiene::MacroKind;
-use std::marker::PhantomData;
-use std::num::NonZeroUsize;
 
 pub(super) trait IsDefault: Default {
     fn is_default(&self) -> bool;
diff --git a/compiler/rustc_middle/src/hir/map/mod.rs b/compiler/rustc_middle/src/hir/map/mod.rs
index f407d30ac82..d376036d832 100644
--- a/compiler/rustc_middle/src/hir/map/mod.rs
+++ b/compiler/rustc_middle/src/hir/map/mod.rs
@@ -10,7 +10,7 @@ use rustc_data_structures::sync::{par_for_each_in, try_par_for_each_in, DynSend,
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::{DefId, LocalDefId, LocalModDefId, LOCAL_CRATE};
 use rustc_hir::definitions::{DefKey, DefPath, DefPathHash};
-use rustc_hir::intravisit::{self, Visitor};
+use rustc_hir::intravisit::Visitor;
 use rustc_hir::*;
 use rustc_index::Idx;
 use rustc_middle::hir::nested_filter;
diff --git a/compiler/rustc_middle/src/middle/limits.rs b/compiler/rustc_middle/src/middle/limits.rs
index d4f023958d6..b29be92ae26 100644
--- a/compiler/rustc_middle/src/middle/limits.rs
+++ b/compiler/rustc_middle/src/middle/limits.rs
@@ -8,7 +8,6 @@
 //! this via an attribute on the crate like `#![recursion_limit="22"]`. This pass
 //! just peeks and looks for that attribute.
 
-use crate::bug;
 use crate::error::LimitInvalid;
 use crate::query::Providers;
 use rustc_ast::Attribute;
diff --git a/compiler/rustc_middle/src/mir/consts.rs b/compiler/rustc_middle/src/mir/consts.rs
index 26138157b74..2c38f998c95 100644
--- a/compiler/rustc_middle/src/mir/consts.rs
+++ b/compiler/rustc_middle/src/mir/consts.rs
@@ -1,6 +1,5 @@
 use std::fmt::{self, Debug, Display, Formatter};
 
-use rustc_hir;
 use rustc_hir::def_id::DefId;
 use rustc_session::RemapFileNameExt;
 use rustc_span::Span;
diff --git a/compiler/rustc_middle/src/mir/generic_graph.rs b/compiler/rustc_middle/src/mir/generic_graph.rs
index d1753427e74..51e26ab7984 100644
--- a/compiler/rustc_middle/src/mir/generic_graph.rs
+++ b/compiler/rustc_middle/src/mir/generic_graph.rs
@@ -1,7 +1,5 @@
 use gsgdt::{Edge, Graph, Node, NodeStyle};
-use rustc_hir::def_id::DefId;
 use rustc_middle::mir::*;
-use rustc_middle::ty::TyCtxt;
 
 /// Convert an MIR function into a gsgdt Graph
 pub fn mir_fn_to_generic_graph<'tcx>(tcx: TyCtxt<'tcx>, body: &Body<'_>) -> Graph {
diff --git a/compiler/rustc_middle/src/mir/graphviz.rs b/compiler/rustc_middle/src/mir/graphviz.rs
index 5c7de864430..96bef40dac5 100644
--- a/compiler/rustc_middle/src/mir/graphviz.rs
+++ b/compiler/rustc_middle/src/mir/graphviz.rs
@@ -1,9 +1,6 @@
 use gsgdt::GraphvizSettings;
 use rustc_graphviz as dot;
-use rustc_hir::def_id::DefId;
 use rustc_middle::mir::*;
-use rustc_middle::ty::{self, TyCtxt};
-use std::fmt::Debug;
 use std::io::{self, Write};
 
 use super::generic_graph::mir_fn_to_generic_graph;
diff --git a/compiler/rustc_middle/src/mir/patch.rs b/compiler/rustc_middle/src/mir/patch.rs
index eb4aa9eb95c..b81e9fa1aab 100644
--- a/compiler/rustc_middle/src/mir/patch.rs
+++ b/compiler/rustc_middle/src/mir/patch.rs
@@ -1,7 +1,4 @@
-use rustc_index::{Idx, IndexVec};
 use rustc_middle::mir::*;
-use rustc_middle::ty::Ty;
-use rustc_span::Span;
 
 /// This struct represents a patch to MIR, which can add
 /// new statements and basic blocks and patch over block
diff --git a/compiler/rustc_middle/src/mir/pretty.rs b/compiler/rustc_middle/src/mir/pretty.rs
index bfaa0d88fc0..071c6a75583 100644
--- a/compiler/rustc_middle/src/mir/pretty.rs
+++ b/compiler/rustc_middle/src/mir/pretty.rs
@@ -1,23 +1,18 @@
 use std::collections::BTreeSet;
-use std::fmt::{self, Debug, Display, Write as _};
+use std::fmt::{Display, Write as _};
 use std::fs;
 use std::io::{self, Write as _};
 use std::path::{Path, PathBuf};
 
 use super::graphviz::write_mir_fn_graphviz;
 use super::spanview::write_mir_fn_spanview;
-use either::Either;
 use rustc_ast::InlineAsmTemplatePiece;
-use rustc_data_structures::fx::FxHashMap;
-use rustc_hir::def_id::DefId;
-use rustc_index::Idx;
 use rustc_middle::mir::interpret::{
-    alloc_range, read_target_uint, AllocBytes, AllocId, Allocation, ConstAllocation, GlobalAlloc,
-    Pointer, Provenance,
+    alloc_range, read_target_uint, AllocBytes, AllocId, Allocation, GlobalAlloc, Pointer,
+    Provenance,
 };
 use rustc_middle::mir::visit::Visitor;
 use rustc_middle::mir::{self, *};
-use rustc_middle::ty::{self, TyCtxt};
 use rustc_target::abi::Size;
 
 const INDENT: &str = "    ";
diff --git a/compiler/rustc_middle/src/mir/spanview.rs b/compiler/rustc_middle/src/mir/spanview.rs
index 46e5c74c73c..cb9fc0d37f2 100644
--- a/compiler/rustc_middle/src/mir/spanview.rs
+++ b/compiler/rustc_middle/src/mir/spanview.rs
@@ -1,9 +1,7 @@
-use rustc_hir::def_id::DefId;
 use rustc_middle::hir;
 use rustc_middle::mir::*;
-use rustc_middle::ty::TyCtxt;
 use rustc_session::config::MirSpanview;
-use rustc_span::{BytePos, Pos, Span};
+use rustc_span::{BytePos, Pos};
 
 use std::cmp;
 use std::io::{self, Write};
diff --git a/compiler/rustc_middle/src/mir/tcx.rs b/compiler/rustc_middle/src/mir/tcx.rs
index 0fc12586948..f9b2a6ee8aa 100644
--- a/compiler/rustc_middle/src/mir/tcx.rs
+++ b/compiler/rustc_middle/src/mir/tcx.rs
@@ -4,9 +4,7 @@
  */
 
 use crate::mir::*;
-use crate::ty::{self, Ty, TyCtxt};
 use rustc_hir as hir;
-use rustc_target::abi::{FieldIdx, VariantIdx};
 
 #[derive(Copy, Clone, Debug, TypeFoldable, TypeVisitable)]
 pub struct PlaceTy<'tcx> {
diff --git a/compiler/rustc_middle/src/mir/terminator.rs b/compiler/rustc_middle/src/mir/terminator.rs
index aa4cb36c5ce..98e3a1f604e 100644
--- a/compiler/rustc_middle/src/mir/terminator.rs
+++ b/compiler/rustc_middle/src/mir/terminator.rs
@@ -2,9 +2,8 @@
 use rustc_hir::LangItem;
 use smallvec::SmallVec;
 
-use super::{BasicBlock, InlineAsmOperand, Operand, SourceInfo, TerminatorKind, UnwindAction};
+use super::TerminatorKind;
 use rustc_macros::HashStable;
-use std::iter;
 use std::slice;
 
 use super::*;
diff --git a/compiler/rustc_middle/src/mir/type_foldable.rs b/compiler/rustc_middle/src/mir/type_foldable.rs
index d5c81b6cd79..ea6b44d62b0 100644
--- a/compiler/rustc_middle/src/mir/type_foldable.rs
+++ b/compiler/rustc_middle/src/mir/type_foldable.rs
@@ -3,7 +3,6 @@
 use rustc_ast::InlineAsmTemplatePiece;
 
 use super::*;
-use crate::ty;
 
 TrivialTypeTraversalImpls! {
     BlockTailInfo,
diff --git a/compiler/rustc_middle/src/mir/visit.rs b/compiler/rustc_middle/src/mir/visit.rs
index d47cfd5712f..9059936f495 100644
--- a/compiler/rustc_middle/src/mir/visit.rs
+++ b/compiler/rustc_middle/src/mir/visit.rs
@@ -63,9 +63,7 @@
 //! `is_cleanup` above.
 
 use crate::mir::*;
-use crate::ty::GenericArgsRef;
-use crate::ty::{self, CanonicalUserTypeAnnotation, Ty};
-use rustc_span::Span;
+use crate::ty::CanonicalUserTypeAnnotation;
 
 macro_rules! make_mir_visitor {
     ($visitor_trait_name:ident, $($mutability:ident)?) => {
diff --git a/compiler/rustc_middle/src/ty/generic_args.rs b/compiler/rustc_middle/src/ty/generic_args.rs
index fa68923b2c1..63f4bab7914 100644
--- a/compiler/rustc_middle/src/ty/generic_args.rs
+++ b/compiler/rustc_middle/src/ty/generic_args.rs
@@ -10,7 +10,7 @@ use rustc_data_structures::intern::Interned;
 use rustc_errors::{DiagnosticArgValue, IntoDiagnosticArg};
 use rustc_hir::def_id::DefId;
 use rustc_macros::HashStable;
-use rustc_serialize::{self, Decodable, Encodable};
+use rustc_serialize::{Decodable, Encodable};
 use rustc_type_ir::WithCachedTypeInfo;
 use smallvec::SmallVec;
 
diff --git a/compiler/rustc_middle/src/ty/layout.rs b/compiler/rustc_middle/src/ty/layout.rs
index e1d1f361091..5fcdd5d4d2e 100644
--- a/compiler/rustc_middle/src/ty/layout.rs
+++ b/compiler/rustc_middle/src/ty/layout.rs
@@ -2,7 +2,7 @@ use crate::error::UnsupportedFnAbi;
 use crate::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use crate::query::TyCtxtAt;
 use crate::ty::normalize_erasing_regions::NormalizationError;
-use crate::ty::{self, ConstKind, ReprOptions, Ty, TyCtxt, TypeVisitableExt};
+use crate::ty::{self, ConstKind, Ty, TyCtxt, TypeVisitableExt};
 use rustc_error_messages::DiagnosticMessage;
 use rustc_errors::{
     DiagnosticArgValue, DiagnosticBuilder, Handler, IntoDiagnostic, IntoDiagnosticArg,
diff --git a/compiler/rustc_middle/src/ty/print/pretty.rs b/compiler/rustc_middle/src/ty/print/pretty.rs
index bd9f0fd3ea9..68d92e9e303 100644
--- a/compiler/rustc_middle/src/ty/print/pretty.rs
+++ b/compiler/rustc_middle/src/ty/print/pretty.rs
@@ -2,19 +2,18 @@ use crate::mir::interpret::{AllocRange, GlobalAlloc, Pointer, Provenance, Scalar
 use crate::query::IntoQueryParam;
 use crate::query::Providers;
 use crate::traits::util::supertraits_for_pretty_printing;
+use crate::ty::GenericArgKind;
 use crate::ty::{
-    self, ConstInt, ParamConst, ScalarInt, Term, TermKind, Ty, TyCtxt, TypeFoldable,
-    TypeSuperFoldable, TypeSuperVisitable, TypeVisitable, TypeVisitableExt,
+    ConstInt, ParamConst, ScalarInt, Term, TermKind, TypeFoldable, TypeSuperFoldable,
+    TypeSuperVisitable, TypeVisitable, TypeVisitableExt,
 };
-use crate::ty::{GenericArg, GenericArgKind};
 use rustc_apfloat::ieee::{Double, Single};
 use rustc_apfloat::Float;
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
-use rustc_data_structures::sso::SsoHashSet;
 use rustc_hir as hir;
 use rustc_hir::def::{self, CtorKind, DefKind, Namespace};
-use rustc_hir::def_id::{DefId, DefIdSet, ModDefId, CRATE_DEF_ID, LOCAL_CRATE};
-use rustc_hir::definitions::{DefKey, DefPathData, DefPathDataName, DisambiguatedDefPathData};
+use rustc_hir::def_id::{DefIdSet, ModDefId, CRATE_DEF_ID, LOCAL_CRATE};
+use rustc_hir::definitions::{DefKey, DefPathDataName};
 use rustc_hir::LangItem;
 use rustc_session::config::TrimmedDefPaths;
 use rustc_session::cstore::{ExternCrate, ExternCrateSource};
diff --git a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs
index 2130dbdc033..a5f6bb12ee4 100644
--- a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs
+++ b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs
@@ -10,8 +10,6 @@ use crate::build::{BlockAnd, BlockAndExtension, Builder, NeedsTemporary};
 use rustc_hir::lang_items::LangItem;
 use rustc_middle::middle::region;
 use rustc_middle::mir::interpret::Scalar;
-use rustc_middle::mir::AssertKind;
-use rustc_middle::mir::Place;
 use rustc_middle::mir::*;
 use rustc_middle::thir::*;
 use rustc_middle::ty::cast::{mir_cast_kind, CastTy};
diff --git a/compiler/rustc_mir_build/src/check_unsafety.rs b/compiler/rustc_mir_build/src/check_unsafety.rs
index 1f7c6d7875b..62190848dd5 100644
--- a/compiler/rustc_mir_build/src/check_unsafety.rs
+++ b/compiler/rustc_mir_build/src/check_unsafety.rs
@@ -2,7 +2,7 @@ use std::borrow::Cow;
 
 use crate::build::ExprCategory;
 use crate::errors::*;
-use rustc_middle::thir::visit::{self, Visitor};
+use rustc_middle::thir::visit::Visitor;
 
 use rustc_errors::DiagnosticArgValue;
 use rustc_hir as hir;
diff --git a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
index 41510d31530..fcd548821f2 100644
--- a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
+++ b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
@@ -14,7 +14,7 @@ use rustc_hir as hir;
 use rustc_hir::def::*;
 use rustc_hir::def_id::LocalDefId;
 use rustc_hir::HirId;
-use rustc_middle::thir::visit::{self, Visitor};
+use rustc_middle::thir::visit::Visitor;
 use rustc_middle::thir::*;
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{self, AdtDef, Ty, TyCtxt};
diff --git a/compiler/rustc_mir_dataflow/src/framework/tests.rs b/compiler/rustc_mir_dataflow/src/framework/tests.rs
index 1da5057ff40..6b338efd569 100644
--- a/compiler/rustc_mir_dataflow/src/framework/tests.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/tests.rs
@@ -2,9 +2,7 @@
 
 use std::marker::PhantomData;
 
-use rustc_index::bit_set::BitSet;
 use rustc_index::IndexVec;
-use rustc_middle::mir::{self, BasicBlock, Location};
 use rustc_middle::ty;
 use rustc_span::DUMMY_SP;
 
diff --git a/compiler/rustc_mir_transform/src/abort_unwinding_calls.rs b/compiler/rustc_mir_transform/src/abort_unwinding_calls.rs
index 2b3d423ea61..dfc7a9891f9 100644
--- a/compiler/rustc_mir_transform/src/abort_unwinding_calls.rs
+++ b/compiler/rustc_mir_transform/src/abort_unwinding_calls.rs
@@ -1,4 +1,3 @@
-use crate::MirPass;
 use rustc_ast::InlineAsmOptions;
 use rustc_middle::mir::*;
 use rustc_middle::ty::layout;
diff --git a/compiler/rustc_mir_transform/src/add_call_guards.rs b/compiler/rustc_mir_transform/src/add_call_guards.rs
index b814fbf32b1..a47c8d94bba 100644
--- a/compiler/rustc_mir_transform/src/add_call_guards.rs
+++ b/compiler/rustc_mir_transform/src/add_call_guards.rs
@@ -1,4 +1,3 @@
-use crate::MirPass;
 use rustc_index::{Idx, IndexVec};
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
diff --git a/compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs b/compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs
index ef2a0c790e9..de6d20ae3e8 100644
--- a/compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs
+++ b/compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs
@@ -2,7 +2,6 @@ use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 
 use crate::util;
-use crate::MirPass;
 use rustc_middle::mir::patch::MirPatch;
 
 /// This pass moves values being dropped that are within a packed
diff --git a/compiler/rustc_mir_transform/src/add_retag.rs b/compiler/rustc_mir_transform/src/add_retag.rs
index 75473ca53fb..94077c63057 100644
--- a/compiler/rustc_mir_transform/src/add_retag.rs
+++ b/compiler/rustc_mir_transform/src/add_retag.rs
@@ -4,7 +4,6 @@
 //! of MIR building, and only after this pass we think of the program has having the
 //! normal MIR semantics.
 
-use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 
diff --git a/compiler/rustc_mir_transform/src/add_subtyping_projections.rs b/compiler/rustc_mir_transform/src/add_subtyping_projections.rs
index e5be7c0ca76..04204c68f7b 100644
--- a/compiler/rustc_mir_transform/src/add_subtyping_projections.rs
+++ b/compiler/rustc_mir_transform/src/add_subtyping_projections.rs
@@ -1,4 +1,3 @@
-use crate::MirPass;
 use rustc_index::IndexVec;
 use rustc_middle::mir::patch::MirPatch;
 use rustc_middle::mir::visit::MutVisitor;
diff --git a/compiler/rustc_mir_transform/src/check_alignment.rs b/compiler/rustc_mir_transform/src/check_alignment.rs
index 42b2f18869c..9eec724ef21 100644
--- a/compiler/rustc_mir_transform/src/check_alignment.rs
+++ b/compiler/rustc_mir_transform/src/check_alignment.rs
@@ -1,4 +1,3 @@
-use crate::MirPass;
 use rustc_hir::lang_items::LangItem;
 use rustc_index::IndexVec;
 use rustc_middle::mir::*;
diff --git a/compiler/rustc_mir_transform/src/const_goto.rs b/compiler/rustc_mir_transform/src/const_goto.rs
index fd2d37dbea5..3884346076e 100644
--- a/compiler/rustc_mir_transform/src/const_goto.rs
+++ b/compiler/rustc_mir_transform/src/const_goto.rs
@@ -17,7 +17,6 @@
 //! }
 //! ```
 
-use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 use rustc_middle::{mir::visit::Visitor, ty::ParamEnv};
diff --git a/compiler/rustc_mir_transform/src/const_prop.rs b/compiler/rustc_mir_transform/src/const_prop.rs
index d88b33cc973..e66d5e0a9f9 100644
--- a/compiler/rustc_mir_transform/src/const_prop.rs
+++ b/compiler/rustc_mir_transform/src/const_prop.rs
@@ -19,7 +19,6 @@ use rustc_target::abi::{self, HasDataLayout, Size, TargetDataLayout};
 use rustc_target::spec::abi::Abi as CallAbi;
 
 use crate::dataflow_const_prop::Patch;
-use crate::MirPass;
 use rustc_const_eval::interpret::{
     self, compile_time_machine, AllocId, ConstAllocation, FnArg, Frame, ImmTy, Immediate, InterpCx,
     InterpResult, MemoryKind, OpTy, PlaceTy, Pointer, Scalar, StackPopCleanup,
diff --git a/compiler/rustc_mir_transform/src/copy_prop.rs b/compiler/rustc_mir_transform/src/copy_prop.rs
index 74009496e75..0119b95cced 100644
--- a/compiler/rustc_mir_transform/src/copy_prop.rs
+++ b/compiler/rustc_mir_transform/src/copy_prop.rs
@@ -6,7 +6,6 @@ use rustc_middle::ty::TyCtxt;
 use rustc_mir_dataflow::impls::borrowed_locals;
 
 use crate::ssa::SsaLocals;
-use crate::MirPass;
 
 /// Unify locals that copy each other.
 ///
diff --git a/compiler/rustc_mir_transform/src/coroutine.rs b/compiler/rustc_mir_transform/src/coroutine.rs
index 737fb6bf612..ed8b4ef3ba4 100644
--- a/compiler/rustc_mir_transform/src/coroutine.rs
+++ b/compiler/rustc_mir_transform/src/coroutine.rs
@@ -55,7 +55,6 @@ use crate::deref_separator::deref_finder;
 use crate::errors;
 use crate::pass_manager as pm;
 use crate::simplify;
-use crate::MirPass;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::pluralize;
 use rustc_hir as hir;
@@ -63,7 +62,6 @@ use rustc_hir::lang_items::LangItem;
 use rustc_hir::CoroutineKind;
 use rustc_index::bit_set::{BitMatrix, BitSet, GrowableBitSet};
 use rustc_index::{Idx, IndexVec};
-use rustc_middle::mir::dump_mir;
 use rustc_middle::mir::visit::{MutVisitor, PlaceContext, Visitor};
 use rustc_middle::mir::*;
 use rustc_middle::ty::CoroutineArgs;
@@ -73,7 +71,7 @@ use rustc_mir_dataflow::impls::{
     MaybeBorrowedLocals, MaybeLiveLocals, MaybeRequiresStorage, MaybeStorageLive,
 };
 use rustc_mir_dataflow::storage::always_storage_live_locals;
-use rustc_mir_dataflow::{self, Analysis};
+use rustc_mir_dataflow::Analysis;
 use rustc_span::def_id::{DefId, LocalDefId};
 use rustc_span::symbol::sym;
 use rustc_span::Span;
diff --git a/compiler/rustc_mir_transform/src/coverage/query.rs b/compiler/rustc_mir_transform/src/coverage/query.rs
index 809407f897d..dfc7c3a713b 100644
--- a/compiler/rustc_mir_transform/src/coverage/query.rs
+++ b/compiler/rustc_mir_transform/src/coverage/query.rs
@@ -2,9 +2,9 @@ use super::*;
 
 use rustc_data_structures::captures::Captures;
 use rustc_middle::mir::coverage::*;
-use rustc_middle::mir::{Body, Coverage, CoverageIdsInfo};
+use rustc_middle::mir::{Body, CoverageIdsInfo};
 use rustc_middle::query::Providers;
-use rustc_middle::ty::{self, TyCtxt};
+use rustc_middle::ty::{self};
 
 /// A `query` provider for retrieving coverage information injected into MIR.
 pub(crate) fn provide(providers: &mut Providers) {
diff --git a/compiler/rustc_mir_transform/src/coverage/tests.rs b/compiler/rustc_mir_transform/src/coverage/tests.rs
index 302cbf05d78..931bc8e58ff 100644
--- a/compiler/rustc_mir_transform/src/coverage/tests.rs
+++ b/compiler/rustc_mir_transform/src/coverage/tests.rs
@@ -33,7 +33,7 @@ use rustc_data_structures::graph::WithSuccessors;
 use rustc_index::{Idx, IndexVec};
 use rustc_middle::mir::*;
 use rustc_middle::ty;
-use rustc_span::{self, BytePos, Pos, Span, DUMMY_SP};
+use rustc_span::{BytePos, Pos, Span, DUMMY_SP};
 
 fn bcb(index: u32) -> BasicCoverageBlock {
     BasicCoverageBlock::from_u32(index)
diff --git a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs
index e9949ebbc87..146cc33e8c6 100644
--- a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs
+++ b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs
@@ -20,7 +20,6 @@ use rustc_span::DUMMY_SP;
 use rustc_target::abi::{Abi, FieldIdx, Size, VariantIdx, FIRST_VARIANT};
 
 use crate::const_prop::throw_machine_stop_str;
-use crate::MirPass;
 
 // These constants are somewhat random guesses and have not been optimized.
 // If `tcx.sess.mir_opt_level() >= 4`, we ignore the limits (this can become very expensive).
diff --git a/compiler/rustc_mir_transform/src/deduplicate_blocks.rs b/compiler/rustc_mir_transform/src/deduplicate_blocks.rs
index 666293cbc30..b40b2ec8bfd 100644
--- a/compiler/rustc_mir_transform/src/deduplicate_blocks.rs
+++ b/compiler/rustc_mir_transform/src/deduplicate_blocks.rs
@@ -3,8 +3,6 @@
 
 use std::{collections::hash_map::Entry, hash::Hash, hash::Hasher, iter};
 
-use crate::MirPass;
-
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::mir::visit::MutVisitor;
 use rustc_middle::mir::*;
diff --git a/compiler/rustc_mir_transform/src/deref_separator.rs b/compiler/rustc_mir_transform/src/deref_separator.rs
index 42be7457018..0e2fccc85da 100644
--- a/compiler/rustc_mir_transform/src/deref_separator.rs
+++ b/compiler/rustc_mir_transform/src/deref_separator.rs
@@ -1,4 +1,3 @@
-use crate::MirPass;
 use rustc_index::IndexVec;
 use rustc_middle::mir::patch::MirPatch;
 use rustc_middle::mir::visit::NonUseContext::VarDebugInfo;
diff --git a/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs b/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs
index 1c917a85c03..96943435bab 100644
--- a/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs
+++ b/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs
@@ -2,7 +2,6 @@
 //!
 //! Box is not actually a pointer so it is incorrect to dereference it directly.
 
-use crate::MirPass;
 use rustc_hir::def_id::DefId;
 use rustc_index::Idx;
 use rustc_middle::mir::patch::MirPatch;
diff --git a/compiler/rustc_mir_transform/src/elaborate_drops.rs b/compiler/rustc_mir_transform/src/elaborate_drops.rs
index f7188ea83fc..c45badbc559 100644
--- a/compiler/rustc_mir_transform/src/elaborate_drops.rs
+++ b/compiler/rustc_mir_transform/src/elaborate_drops.rs
@@ -1,5 +1,4 @@
 use crate::deref_separator::deref_finder;
-use crate::MirPass;
 use rustc_index::bit_set::BitSet;
 use rustc_index::IndexVec;
 use rustc_middle::mir::patch::MirPatch;
diff --git a/compiler/rustc_mir_transform/src/gvn.rs b/compiler/rustc_mir_transform/src/gvn.rs
index 1a5979ef714..b21988e179d 100644
--- a/compiler/rustc_mir_transform/src/gvn.rs
+++ b/compiler/rustc_mir_transform/src/gvn.rs
@@ -103,7 +103,6 @@ use std::borrow::Cow;
 
 use crate::dataflow_const_prop::DummyMachine;
 use crate::ssa::{AssignedValue, SsaLocals};
-use crate::MirPass;
 use either::Either;
 
 pub struct GVN;
diff --git a/compiler/rustc_mir_transform/src/inline.rs b/compiler/rustc_mir_transform/src/inline.rs
index 8fa26713184..8ad804bf3e7 100644
--- a/compiler/rustc_mir_transform/src/inline.rs
+++ b/compiler/rustc_mir_transform/src/inline.rs
@@ -17,7 +17,6 @@ use rustc_target::spec::abi::Abi;
 use crate::cost_checker::CostChecker;
 use crate::simplify::{remove_dead_blocks, CfgSimplifier};
 use crate::util;
-use crate::MirPass;
 use std::iter;
 use std::ops::{Range, RangeFrom};
 
diff --git a/compiler/rustc_mir_transform/src/instsimplify.rs b/compiler/rustc_mir_transform/src/instsimplify.rs
index 7a844b01707..4f0f63d22a4 100644
--- a/compiler/rustc_mir_transform/src/instsimplify.rs
+++ b/compiler/rustc_mir_transform/src/instsimplify.rs
@@ -1,8 +1,6 @@
 //! Performs various peephole optimizations.
 
 use crate::simplify::simplify_duplicate_switch_targets;
-use crate::MirPass;
-use rustc_hir::Mutability;
 use rustc_middle::mir::*;
 use rustc_middle::ty::layout::ValidityRequirement;
 use rustc_middle::ty::{self, GenericArgsRef, ParamEnv, Ty, TyCtxt};
diff --git a/compiler/rustc_mir_transform/src/jump_threading.rs b/compiler/rustc_mir_transform/src/jump_threading.rs
index 5754dd08164..36a15f47276 100644
--- a/compiler/rustc_mir_transform/src/jump_threading.rs
+++ b/compiler/rustc_mir_transform/src/jump_threading.rs
@@ -45,7 +45,6 @@ use rustc_middle::ty::{self, ScalarInt, Ty, TyCtxt};
 use rustc_mir_dataflow::value_analysis::{Map, PlaceIndex, State, TrackElem};
 
 use crate::cost_checker::CostChecker;
-use crate::MirPass;
 
 pub struct JumpThreading;
 
diff --git a/compiler/rustc_mir_transform/src/large_enums.rs b/compiler/rustc_mir_transform/src/large_enums.rs
index 0a8b13d6677..1d788a55ff8 100644
--- a/compiler/rustc_mir_transform/src/large_enums.rs
+++ b/compiler/rustc_mir_transform/src/large_enums.rs
@@ -1,5 +1,4 @@
 use crate::rustc_middle::ty::util::IntTypeExt;
-use crate::MirPass;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::mir::interpret::AllocId;
 use rustc_middle::mir::*;
diff --git a/compiler/rustc_mir_transform/src/lower_intrinsics.rs b/compiler/rustc_mir_transform/src/lower_intrinsics.rs
index 249e0fc633e..18f588dccf6 100644
--- a/compiler/rustc_mir_transform/src/lower_intrinsics.rs
+++ b/compiler/rustc_mir_transform/src/lower_intrinsics.rs
@@ -1,6 +1,5 @@
 //! Lowers intrinsic calls
 
-use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_span::symbol::sym;
diff --git a/compiler/rustc_mir_transform/src/lower_slice_len.rs b/compiler/rustc_mir_transform/src/lower_slice_len.rs
index ae487841179..daeb56666f4 100644
--- a/compiler/rustc_mir_transform/src/lower_slice_len.rs
+++ b/compiler/rustc_mir_transform/src/lower_slice_len.rs
@@ -1,7 +1,6 @@
 //! This pass lowers calls to core::slice::len to just Len op.
 //! It should run before inlining!
 
-use crate::MirPass;
 use rustc_hir::def_id::DefId;
 use rustc_index::IndexSlice;
 use rustc_middle::mir::*;
diff --git a/compiler/rustc_mir_transform/src/match_branches.rs b/compiler/rustc_mir_transform/src/match_branches.rs
index 3dc627b6146..1c4aa37d57f 100644
--- a/compiler/rustc_mir_transform/src/match_branches.rs
+++ b/compiler/rustc_mir_transform/src/match_branches.rs
@@ -1,4 +1,3 @@
-use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 use std::iter;
diff --git a/compiler/rustc_mir_transform/src/multiple_return_terminators.rs b/compiler/rustc_mir_transform/src/multiple_return_terminators.rs
index c9b42e75cb2..64749a4b5b6 100644
--- a/compiler/rustc_mir_transform/src/multiple_return_terminators.rs
+++ b/compiler/rustc_mir_transform/src/multiple_return_terminators.rs
@@ -1,7 +1,7 @@
 //! This pass removes jumps to basic blocks containing only a return, and replaces them with a
 //! return instead.
 
-use crate::{simplify, MirPass};
+use crate::simplify;
 use rustc_index::bit_set::BitSet;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
diff --git a/compiler/rustc_mir_transform/src/normalize_array_len.rs b/compiler/rustc_mir_transform/src/normalize_array_len.rs
index 206cdf9fe28..128634bd7f2 100644
--- a/compiler/rustc_mir_transform/src/normalize_array_len.rs
+++ b/compiler/rustc_mir_transform/src/normalize_array_len.rs
@@ -2,7 +2,6 @@
 //! is taken using `.len()` method. Handy to preserve information in MIR for const prop
 
 use crate::ssa::SsaLocals;
-use crate::MirPass;
 use rustc_index::IndexVec;
 use rustc_middle::mir::visit::*;
 use rustc_middle::mir::*;
diff --git a/compiler/rustc_mir_transform/src/prettify.rs b/compiler/rustc_mir_transform/src/prettify.rs
index 745fa30841c..7b77d032353 100644
--- a/compiler/rustc_mir_transform/src/prettify.rs
+++ b/compiler/rustc_mir_transform/src/prettify.rs
@@ -4,7 +4,6 @@
 //! (`-Zmir-enable-passes=+ReorderBasicBlocks,+ReorderLocals`)
 //! to make the MIR easier to read for humans.
 
-use crate::MirPass;
 use rustc_index::{bit_set::BitSet, IndexSlice, IndexVec};
 use rustc_middle::mir::visit::{MutVisitor, PlaceContext, Visitor};
 use rustc_middle::mir::*;
diff --git a/compiler/rustc_mir_transform/src/ref_prop.rs b/compiler/rustc_mir_transform/src/ref_prop.rs
index df39c819ba9..f13ab5b0f1f 100644
--- a/compiler/rustc_mir_transform/src/ref_prop.rs
+++ b/compiler/rustc_mir_transform/src/ref_prop.rs
@@ -9,7 +9,6 @@ use rustc_mir_dataflow::storage::always_storage_live_locals;
 use rustc_mir_dataflow::Analysis;
 
 use crate::ssa::{SsaLocals, StorageLiveLocals};
-use crate::MirPass;
 
 /// Propagate references using SSA analysis.
 ///
diff --git a/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs b/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs
index 54892442c87..095119e2e3f 100644
--- a/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs
+++ b/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs
@@ -1,4 +1,3 @@
-use crate::MirPass;
 use rustc_index::bit_set::BitSet;
 use rustc_middle::mir::patch::MirPatch;
 use rustc_middle::mir::*;
diff --git a/compiler/rustc_mir_transform/src/remove_place_mention.rs b/compiler/rustc_mir_transform/src/remove_place_mention.rs
index 8be1c37572d..78335b3b5e0 100644
--- a/compiler/rustc_mir_transform/src/remove_place_mention.rs
+++ b/compiler/rustc_mir_transform/src/remove_place_mention.rs
@@ -1,6 +1,5 @@
 //! This pass removes `PlaceMention` statement, which has no effect at codegen.
 
-use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 
diff --git a/compiler/rustc_mir_transform/src/remove_storage_markers.rs b/compiler/rustc_mir_transform/src/remove_storage_markers.rs
index dbe082e9093..795f5232ee3 100644
--- a/compiler/rustc_mir_transform/src/remove_storage_markers.rs
+++ b/compiler/rustc_mir_transform/src/remove_storage_markers.rs
@@ -1,6 +1,5 @@
 //! This pass removes storage markers if they won't be emitted during codegen.
 
-use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 
diff --git a/compiler/rustc_mir_transform/src/remove_uninit_drops.rs b/compiler/rustc_mir_transform/src/remove_uninit_drops.rs
index 548879e2e39..7d12bcf2fa1 100644
--- a/compiler/rustc_mir_transform/src/remove_uninit_drops.rs
+++ b/compiler/rustc_mir_transform/src/remove_uninit_drops.rs
@@ -4,9 +4,7 @@ use rustc_middle::ty::GenericArgsRef;
 use rustc_middle::ty::{self, ParamEnv, Ty, TyCtxt, VariantDef};
 use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
 use rustc_mir_dataflow::move_paths::{LookupResult, MoveData, MovePathIndex};
-use rustc_mir_dataflow::{
-    self, move_path_children_matching, Analysis, MaybeReachable, MoveDataParamEnv,
-};
+use rustc_mir_dataflow::{move_path_children_matching, Analysis, MaybeReachable, MoveDataParamEnv};
 use rustc_target::abi::FieldIdx;
 
 use crate::MirPass;
diff --git a/compiler/rustc_mir_transform/src/remove_unneeded_drops.rs b/compiler/rustc_mir_transform/src/remove_unneeded_drops.rs
index 08b2a6537e9..5d528bed356 100644
--- a/compiler/rustc_mir_transform/src/remove_unneeded_drops.rs
+++ b/compiler/rustc_mir_transform/src/remove_unneeded_drops.rs
@@ -4,7 +4,6 @@
 //! useful because (unlike MIR building) it runs after type checking, so it can make use of
 //! `Reveal::All` to provide more precise type information.
 
-use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 
diff --git a/compiler/rustc_mir_transform/src/remove_zsts.rs b/compiler/rustc_mir_transform/src/remove_zsts.rs
index 9f59f9d1245..34d57a45301 100644
--- a/compiler/rustc_mir_transform/src/remove_zsts.rs
+++ b/compiler/rustc_mir_transform/src/remove_zsts.rs
@@ -1,6 +1,5 @@
 //! Removes operations on ZST places, and convert ZST operands to constants.
 
-use crate::MirPass;
 use rustc_middle::mir::visit::*;
 use rustc_middle::mir::*;
 use rustc_middle::ty::{self, Ty, TyCtxt};
diff --git a/compiler/rustc_mir_transform/src/reveal_all.rs b/compiler/rustc_mir_transform/src/reveal_all.rs
index 1626cf3c035..4d2eca57840 100644
--- a/compiler/rustc_mir_transform/src/reveal_all.rs
+++ b/compiler/rustc_mir_transform/src/reveal_all.rs
@@ -1,6 +1,5 @@
 //! Normalizes MIR in RevealAll mode.
 
-use crate::MirPass;
 use rustc_middle::mir::visit::*;
 use rustc_middle::mir::*;
 use rustc_middle::ty::{self, Ty, TyCtxt};
diff --git a/compiler/rustc_mir_transform/src/separate_const_switch.rs b/compiler/rustc_mir_transform/src/separate_const_switch.rs
index 907cfe7581a..6e22690d8da 100644
--- a/compiler/rustc_mir_transform/src/separate_const_switch.rs
+++ b/compiler/rustc_mir_transform/src/separate_const_switch.rs
@@ -37,7 +37,6 @@
 //! simplicity rather than completeness (it notably
 //! sometimes duplicates abusively).
 
-use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 use smallvec::SmallVec;
diff --git a/compiler/rustc_mir_transform/src/simplify.rs b/compiler/rustc_mir_transform/src/simplify.rs
index 97d398fe5c9..856a0f22771 100644
--- a/compiler/rustc_mir_transform/src/simplify.rs
+++ b/compiler/rustc_mir_transform/src/simplify.rs
@@ -27,7 +27,6 @@
 //! naively generate still contains the `_a = ()` write in the unreachable block "after" the
 //! return.
 
-use crate::MirPass;
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_index::{Idx, IndexSlice, IndexVec};
 use rustc_middle::mir::visit::{MutVisitor, MutatingUseContext, PlaceContext, Visitor};
diff --git a/compiler/rustc_mir_transform/src/simplify_branches.rs b/compiler/rustc_mir_transform/src/simplify_branches.rs
index 1f0e605c3b8..35a052166bd 100644
--- a/compiler/rustc_mir_transform/src/simplify_branches.rs
+++ b/compiler/rustc_mir_transform/src/simplify_branches.rs
@@ -1,4 +1,3 @@
-use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 
diff --git a/compiler/rustc_mir_transform/src/sroa.rs b/compiler/rustc_mir_transform/src/sroa.rs
index a4ca2b91e82..06d5e17fdd6 100644
--- a/compiler/rustc_mir_transform/src/sroa.rs
+++ b/compiler/rustc_mir_transform/src/sroa.rs
@@ -1,4 +1,3 @@
-use crate::MirPass;
 use rustc_data_structures::flat_map_in_place::FlatMapInPlace;
 use rustc_index::bit_set::{BitSet, GrowableBitSet};
 use rustc_index::IndexVec;
diff --git a/compiler/rustc_mir_transform/src/unreachable_prop.rs b/compiler/rustc_mir_transform/src/unreachable_prop.rs
index 919e8d6a234..f12a6aa2429 100644
--- a/compiler/rustc_mir_transform/src/unreachable_prop.rs
+++ b/compiler/rustc_mir_transform/src/unreachable_prop.rs
@@ -2,7 +2,6 @@
 //! when all of their successors are unreachable. This is achieved through a
 //! post-order traversal of the blocks.
 
-use crate::MirPass;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_middle::mir::interpret::Scalar;
 use rustc_middle::mir::patch::MirPatch;
diff --git a/compiler/rustc_parse/src/parser/attr.rs b/compiler/rustc_parse/src/parser/attr.rs
index 422bb79308d..c9ce896b868 100644
--- a/compiler/rustc_parse/src/parser/attr.rs
+++ b/compiler/rustc_parse/src/parser/attr.rs
@@ -7,7 +7,6 @@ use rustc_ast::attr;
 use rustc_ast::token::{self, Delimiter, Nonterminal};
 use rustc_errors::{error_code, Diagnostic, IntoDiagnostic, PResult};
 use rustc_span::{sym, BytePos, Span};
-use std::convert::TryInto;
 use thin_vec::ThinVec;
 use tracing::debug;
 
diff --git a/compiler/rustc_parse/src/parser/item.rs b/compiler/rustc_parse/src/parser/item.rs
index d22cc04d182..89919247e82 100644
--- a/compiler/rustc_parse/src/parser/item.rs
+++ b/compiler/rustc_parse/src/parser/item.rs
@@ -3,18 +3,12 @@ use super::ty::{AllowPlus, RecoverQPath, RecoverReturnSign};
 use super::{AttrWrapper, FollowedByType, ForceCollect, Parser, PathStyle, TrailingToken};
 use crate::errors::{self, MacroExpandsToAdtField};
 use crate::fluent_generated as fluent;
-use ast::StaticItem;
 use rustc_ast::ast::*;
 use rustc_ast::ptr::P;
 use rustc_ast::token::{self, Delimiter, TokenKind};
 use rustc_ast::tokenstream::{DelimSpan, TokenStream, TokenTree};
 use rustc_ast::util::case::Case;
-use rustc_ast::MacCall;
-use rustc_ast::{self as ast, AttrVec, Attribute, DUMMY_NODE_ID};
-use rustc_ast::{BindingAnnotation, Block, FnDecl, FnSig, Param, SelfKind};
-use rustc_ast::{Const, Defaultness, IsAuto, Mutability, Unsafe, UseTree, UseTreeKind};
-use rustc_ast::{EnumDef, FieldDef, Generics, TraitRef, Ty, TyKind, Variant, VariantData};
-use rustc_ast::{FnHeader, ForeignItem, Path, PathSegment, Visibility, VisibilityKind};
+use rustc_ast::{self as ast};
 use rustc_ast_pretty::pprust;
 use rustc_errors::{
     struct_span_err, Applicability, DiagnosticBuilder, ErrorGuaranteed, IntoDiagnostic, PResult,
diff --git a/compiler/rustc_query_system/src/dep_graph/edges.rs b/compiler/rustc_query_system/src/dep_graph/edges.rs
index 400f128d583..63d46f47f5c 100644
--- a/compiler/rustc_query_system/src/dep_graph/edges.rs
+++ b/compiler/rustc_query_system/src/dep_graph/edges.rs
@@ -1,7 +1,6 @@
 use crate::dep_graph::DepNodeIndex;
 use smallvec::SmallVec;
 use std::hash::{Hash, Hasher};
-use std::iter::Extend;
 use std::ops::Deref;
 
 #[derive(Default, Debug)]
diff --git a/compiler/rustc_query_system/src/query/job.rs b/compiler/rustc_query_system/src/query/job.rs
index d933f897833..c431e966e44 100644
--- a/compiler/rustc_query_system/src/query/job.rs
+++ b/compiler/rustc_query_system/src/query/job.rs
@@ -18,7 +18,6 @@ use std::num::NonZeroU64;
 #[cfg(parallel_compiler)]
 use {
     parking_lot::{Condvar, Mutex},
-    rayon_core,
     rustc_data_structures::fx::FxHashSet,
     rustc_data_structures::{defer, jobserver},
     rustc_span::DUMMY_SP,
diff --git a/compiler/rustc_smir/src/rustc_smir/context.rs b/compiler/rustc_smir/src/rustc_smir/context.rs
index 341c69e9327..22e9f66ba96 100644
--- a/compiler/rustc_smir/src/rustc_smir/context.rs
+++ b/compiler/rustc_smir/src/rustc_smir/context.rs
@@ -16,7 +16,7 @@ use stable_mir::ty::{
     AdtDef, AdtKind, Allocation, ClosureDef, ClosureKind, Const, FieldDef, FnDef, GenericArgs,
     LineInfo, PolyFnSig, RigidTy, Span, Ty, TyKind, VariantDef,
 };
-use stable_mir::{self, Crate, CrateItem, DefId, Error, Filename, ItemKind, Symbol};
+use stable_mir::{Crate, CrateItem, DefId, Error, Filename, ItemKind, Symbol};
 use std::cell::RefCell;
 
 use crate::rustc_internal::{internal, RustcInternal};
diff --git a/compiler/rustc_smir/src/rustc_smir/mod.rs b/compiler/rustc_smir/src/rustc_smir/mod.rs
index 4cb48a12c96..ae6cf3fe3e8 100644
--- a/compiler/rustc_smir/src/rustc_smir/mod.rs
+++ b/compiler/rustc_smir/src/rustc_smir/mod.rs
@@ -14,7 +14,7 @@ use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
 use rustc_span::def_id::{CrateNum, DefId, LOCAL_CRATE};
 use stable_mir::mir::mono::InstanceDef;
 use stable_mir::ty::{ConstId, Span};
-use stable_mir::{self, ItemKind};
+use stable_mir::ItemKind;
 use tracing::debug;
 
 use crate::rustc_internal::IndexMap;
diff --git a/compiler/rustc_span/src/source_map.rs b/compiler/rustc_span/src/source_map.rs
index dcf346acb33..cb10e6bf2ba 100644
--- a/compiler/rustc_span/src/source_map.rs
+++ b/compiler/rustc_span/src/source_map.rs
@@ -11,13 +11,11 @@
 
 use crate::*;
 use rustc_data_structures::fx::FxHashMap;
-use rustc_data_structures::stable_hasher::{Hash128, Hash64, StableHasher};
-use rustc_data_structures::sync::{IntoDynSyncSend, Lrc, MappedReadGuard, ReadGuard, RwLock};
-use std::cmp;
+use rustc_data_structures::sync::{IntoDynSyncSend, MappedReadGuard, ReadGuard, RwLock};
 use std::fs;
 use std::hash::Hash;
 use std::io::{self, BorrowedBuf, Read};
-use std::path::{self, Path, PathBuf};
+use std::path::{self};
 
 #[cfg(test)]
 mod tests;
diff --git a/compiler/rustc_span/src/source_map/tests.rs b/compiler/rustc_span/src/source_map/tests.rs
index 5697969ddb8..113ca493d36 100644
--- a/compiler/rustc_span/src/source_map/tests.rs
+++ b/compiler/rustc_span/src/source_map/tests.rs
@@ -1,7 +1,5 @@
 use super::*;
 
-use rustc_data_structures::sync::{FreezeLock, Lrc};
-
 fn init_source_map() -> SourceMap {
     let sm = SourceMap::new(FilePathMapping::empty());
     sm.new_source_file(PathBuf::from("blork.rs").into(), "first line.\nsecond line".to_string());
diff --git a/compiler/rustc_trait_selection/src/traits/auto_trait.rs b/compiler/rustc_trait_selection/src/traits/auto_trait.rs
index 0b8e6e2ef8b..13a09917c03 100644
--- a/compiler/rustc_trait_selection/src/traits/auto_trait.rs
+++ b/compiler/rustc_trait_selection/src/traits/auto_trait.rs
@@ -5,11 +5,9 @@ use super::*;
 
 use crate::errors::UnableToConstructConstantValue;
 use crate::infer::region_constraints::{Constraint, RegionConstraintData};
-use crate::infer::InferCtxt;
 use crate::traits::project::ProjectAndUnifyResult;
 use rustc_infer::infer::DefineOpaqueTypes;
 use rustc_middle::mir::interpret::ErrorHandled;
-use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{ImplPolarity, Region, RegionVid};
 
 use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexSet};
diff --git a/compiler/rustc_ty_utils/src/layout.rs b/compiler/rustc_ty_utils/src/layout.rs
index 7599aa9fa41..f30c40de698 100644
--- a/compiler/rustc_ty_utils/src/layout.rs
+++ b/compiler/rustc_ty_utils/src/layout.rs
@@ -8,9 +8,7 @@ use rustc_middle::ty::layout::{
     IntegerExt, LayoutCx, LayoutError, LayoutOf, TyAndLayout, MAX_SIMD_LANES,
 };
 use rustc_middle::ty::print::with_no_trimmed_paths;
-use rustc_middle::ty::{
-    self, AdtDef, EarlyBinder, GenericArgsRef, ReprOptions, Ty, TyCtxt, TypeVisitableExt,
-};
+use rustc_middle::ty::{self, AdtDef, EarlyBinder, GenericArgsRef, Ty, TyCtxt, TypeVisitableExt};
 use rustc_session::{DataTypeKind, FieldInfo, FieldKind, SizeKind, VariantInfo};
 use rustc_span::symbol::Symbol;
 use rustc_span::DUMMY_SP;
diff --git a/compiler/stable_mir/src/error.rs b/compiler/stable_mir/src/error.rs
index c6da3ae41d3..7085fa937c9 100644
--- a/compiler/stable_mir/src/error.rs
+++ b/compiler/stable_mir/src/error.rs
@@ -4,7 +4,6 @@
 //! - [CompilerError]: This represents errors that can be raised when invoking the compiler.
 //! - [Error]: Generic error that represents the reason why a request that could not be fulfilled.
 
-use std::convert::From;
 use std::fmt::{Debug, Display, Formatter};
 use std::{error, fmt, io};
 
diff --git a/library/alloc/benches/btree/map.rs b/library/alloc/benches/btree/map.rs
index 7d236647750..4fe07eb0213 100644
--- a/library/alloc/benches/btree/map.rs
+++ b/library/alloc/benches/btree/map.rs
@@ -1,6 +1,5 @@
 use std::collections::BTreeMap;
 use std::ops::RangeBounds;
-use std::vec::Vec;
 
 use rand::{seq::SliceRandom, Rng};
 use test::{black_box, Bencher};
diff --git a/library/alloc/benches/str.rs b/library/alloc/benches/str.rs
index 54af389dedc..c148ab6b220 100644
--- a/library/alloc/benches/str.rs
+++ b/library/alloc/benches/str.rs
@@ -1,4 +1,3 @@
-use core::iter::Iterator;
 use test::{black_box, Bencher};
 
 #[bench]
diff --git a/library/alloc/benches/vec_deque.rs b/library/alloc/benches/vec_deque.rs
index 313a97ed1ff..35939f489b4 100644
--- a/library/alloc/benches/vec_deque.rs
+++ b/library/alloc/benches/vec_deque.rs
@@ -1,4 +1,3 @@
-use core::iter::Iterator;
 use std::{
     collections::{vec_deque, VecDeque},
     mem,
diff --git a/library/alloc/src/collections/binary_heap/tests.rs b/library/alloc/src/collections/binary_heap/tests.rs
index 565a7b7975f..d4bc6226a14 100644
--- a/library/alloc/src/collections/binary_heap/tests.rs
+++ b/library/alloc/src/collections/binary_heap/tests.rs
@@ -1,8 +1,6 @@
 use super::*;
 use crate::boxed::Box;
 use crate::testing::crash_test::{CrashTestDummy, Panic};
-use core::mem;
-use std::iter::TrustedLen;
 use std::panic::{catch_unwind, AssertUnwindSafe};
 
 #[test]
diff --git a/library/alloc/src/collections/btree/map/tests.rs b/library/alloc/src/collections/btree/map/tests.rs
index 8681cfcd617..a1b7cfe6b17 100644
--- a/library/alloc/src/collections/btree/map/tests.rs
+++ b/library/alloc/src/collections/btree/map/tests.rs
@@ -1,4 +1,3 @@
-use super::Entry::{Occupied, Vacant};
 use super::*;
 use crate::boxed::Box;
 use crate::fmt::Debug;
@@ -7,13 +6,9 @@ use crate::string::{String, ToString};
 use crate::testing::crash_test::{CrashTestDummy, Panic};
 use crate::testing::ord_chaos::{Cyclic3, Governed, Governor};
 use crate::testing::rng::DeterministicRng;
-use crate::vec::Vec;
 use core::assert_matches::assert_matches;
-use std::cmp::Ordering;
 use std::iter;
-use std::mem;
-use std::ops::Bound::{self, Excluded, Included, Unbounded};
-use std::ops::RangeBounds;
+use std::ops::Bound::{Excluded, Included, Unbounded};
 use std::panic::{catch_unwind, AssertUnwindSafe};
 use std::sync::atomic::{AtomicUsize, Ordering::SeqCst};
 
diff --git a/library/alloc/src/collections/btree/set/tests.rs b/library/alloc/src/collections/btree/set/tests.rs
index e05bf0e2003..8726c5bfead 100644
--- a/library/alloc/src/collections/btree/set/tests.rs
+++ b/library/alloc/src/collections/btree/set/tests.rs
@@ -1,9 +1,6 @@
 use super::*;
 use crate::testing::crash_test::{CrashTestDummy, Panic};
 use crate::testing::rng::DeterministicRng;
-use crate::vec::Vec;
-use std::cmp::Ordering;
-use std::hash::{Hash, Hasher};
 use std::ops::Bound::{Excluded, Included};
 use std::panic::{catch_unwind, AssertUnwindSafe};
 
diff --git a/library/alloc/src/ffi/c_str/tests.rs b/library/alloc/src/ffi/c_str/tests.rs
index 0b7476d5cc7..9f51e17a427 100644
--- a/library/alloc/src/ffi/c_str/tests.rs
+++ b/library/alloc/src/ffi/c_str/tests.rs
@@ -1,6 +1,4 @@
 use super::*;
-use crate::rc::Rc;
-use crate::sync::Arc;
 use core::assert_matches::assert_matches;
 use core::ffi::FromBytesUntilNulError;
 use core::hash::{Hash, Hasher};
diff --git a/library/alloc/src/rc/tests.rs b/library/alloc/src/rc/tests.rs
index 1f221b86f12..c8a40603d9d 100644
--- a/library/alloc/src/rc/tests.rs
+++ b/library/alloc/src/rc/tests.rs
@@ -1,12 +1,7 @@
 use super::*;
 
-use std::boxed::Box;
 use std::cell::RefCell;
 use std::clone::Clone;
-use std::convert::{From, TryInto};
-use std::mem::drop;
-use std::option::Option::{self, None, Some};
-use std::result::Result::{Err, Ok};
 
 #[test]
 fn test_clone() {
diff --git a/library/alloc/src/sync/tests.rs b/library/alloc/src/sync/tests.rs
index 863d58bdf4d..d37e45569cf 100644
--- a/library/alloc/src/sync/tests.rs
+++ b/library/alloc/src/sync/tests.rs
@@ -1,21 +1,12 @@
 use super::*;
 
-use std::boxed::Box;
 use std::clone::Clone;
-use std::convert::{From, TryInto};
-use std::mem::drop;
-use std::ops::Drop;
-use std::option::Option::{self, None, Some};
-use std::sync::atomic::{
-    self,
-    Ordering::{Acquire, SeqCst},
-};
+use std::option::Option::None;
+use std::sync::atomic::Ordering::SeqCst;
 use std::sync::mpsc::channel;
 use std::sync::Mutex;
 use std::thread;
 
-use crate::vec::Vec;
-
 struct Canary(*mut atomic::AtomicUsize);
 
 impl Drop for Canary {
diff --git a/library/alloc/src/tests.rs b/library/alloc/src/tests.rs
index b1d3a9fa8ac..ab256ceaec3 100644
--- a/library/alloc/src/tests.rs
+++ b/library/alloc/src/tests.rs
@@ -1,8 +1,6 @@
 //! Test for `boxed` mod.
 
 use core::any::Any;
-use core::clone::Clone;
-use core::convert::TryInto;
 use core::ops::Deref;
 
 use std::boxed::Box;
diff --git a/library/alloc/tests/arc.rs b/library/alloc/tests/arc.rs
index ce40b5c9b0a..d564a30b103 100644
--- a/library/alloc/tests/arc.rs
+++ b/library/alloc/tests/arc.rs
@@ -1,6 +1,5 @@
 use std::any::Any;
 use std::cell::RefCell;
-use std::cmp::PartialEq;
 use std::iter::TrustedLen;
 use std::mem;
 use std::sync::{Arc, Weak};
diff --git a/library/alloc/tests/borrow.rs b/library/alloc/tests/borrow.rs
index 57976aa6cdf..af7efb7d782 100644
--- a/library/alloc/tests/borrow.rs
+++ b/library/alloc/tests/borrow.rs
@@ -1,4 +1,4 @@
-use std::borrow::{Cow, ToOwned};
+use std::borrow::Cow;
 use std::ffi::{CStr, OsStr};
 use std::path::Path;
 use std::rc::Rc;
diff --git a/library/alloc/tests/rc.rs b/library/alloc/tests/rc.rs
index efb39a60966..499740e738a 100644
--- a/library/alloc/tests/rc.rs
+++ b/library/alloc/tests/rc.rs
@@ -1,6 +1,5 @@
 use std::any::Any;
 use std::cell::RefCell;
-use std::cmp::PartialEq;
 use std::iter::TrustedLen;
 use std::mem;
 use std::rc::{Rc, Weak};
diff --git a/library/alloc/tests/vec.rs b/library/alloc/tests/vec.rs
index 3d3175ba3a9..9e5910bf126 100644
--- a/library/alloc/tests/vec.rs
+++ b/library/alloc/tests/vec.rs
@@ -1,7 +1,5 @@
-use alloc::vec::Vec;
 use core::alloc::{Allocator, Layout};
 use core::{assert_eq, assert_ne};
-use core::iter::{IntoIterator, Iterator};
 use core::num::NonZeroUsize;
 use core::ptr::NonNull;
 use std::alloc::System;
diff --git a/library/core/benches/num/flt2dec/mod.rs b/library/core/benches/num/flt2dec/mod.rs
index 1a330ef5fe5..b1a9fc56bae 100644
--- a/library/core/benches/num/flt2dec/mod.rs
+++ b/library/core/benches/num/flt2dec/mod.rs
@@ -6,7 +6,6 @@ mod strategy {
 use core::num::flt2dec::MAX_SIG_DIGITS;
 use core::num::flt2dec::{decode, DecodableFloat, Decoded, FullDecoded};
 use std::io::Write;
-use std::vec::Vec;
 use test::{black_box, Bencher};
 
 pub fn decode_finite<T: DecodableFloat>(v: T) -> Decoded {
diff --git a/library/core/benches/num/flt2dec/strategy/dragon.rs b/library/core/benches/num/flt2dec/strategy/dragon.rs
index 377c99effd0..babedc6c0ec 100644
--- a/library/core/benches/num/flt2dec/strategy/dragon.rs
+++ b/library/core/benches/num/flt2dec/strategy/dragon.rs
@@ -1,7 +1,6 @@
 use super::super::*;
 use core::num::flt2dec::strategy::dragon::*;
 use std::mem::MaybeUninit;
-use test::{black_box, Bencher};
 
 #[bench]
 fn bench_small_shortest(b: &mut Bencher) {
diff --git a/library/core/benches/num/flt2dec/strategy/grisu.rs b/library/core/benches/num/flt2dec/strategy/grisu.rs
index 17d6b474ad2..b5bddb2c7c7 100644
--- a/library/core/benches/num/flt2dec/strategy/grisu.rs
+++ b/library/core/benches/num/flt2dec/strategy/grisu.rs
@@ -1,7 +1,6 @@
 use super::super::*;
 use core::num::flt2dec::strategy::grisu::*;
 use std::mem::MaybeUninit;
-use test::{black_box, Bencher};
 
 pub fn decode_finite<T: DecodableFloat>(v: T) -> Decoded {
     match decode(v).1 {
diff --git a/library/core/src/array/iter.rs b/library/core/src/array/iter.rs
index 321357a15bf..2b22488b8ff 100644
--- a/library/core/src/array/iter.rs
+++ b/library/core/src/array/iter.rs
@@ -4,7 +4,7 @@ use crate::num::NonZeroUsize;
 use crate::{
     fmt,
     intrinsics::transmute_unchecked,
-    iter::{self, ExactSizeIterator, FusedIterator, TrustedLen, TrustedRandomAccessNoCoerce},
+    iter::{self, FusedIterator, TrustedLen, TrustedRandomAccessNoCoerce},
     mem::MaybeUninit,
     ops::{IndexRange, Range},
     ptr,
diff --git a/library/core/src/char/methods.rs b/library/core/src/char/methods.rs
index 7ce33bdd411..a93b94867ce 100644
--- a/library/core/src/char/methods.rs
+++ b/library/core/src/char/methods.rs
@@ -1,6 +1,5 @@
 //! impl char {}
 
-use crate::ascii;
 use crate::slice;
 use crate::str::from_utf8_unchecked_mut;
 use crate::unicode::printable::is_printable;
diff --git a/library/core/src/clone.rs b/library/core/src/clone.rs
index d7ca9c22dad..ba86334f950 100644
--- a/library/core/src/clone.rs
+++ b/library/core/src/clone.rs
@@ -210,8 +210,6 @@ pub struct AssertParamIsCopy<T: Copy + ?Sized> {
 /// are implemented in `traits::SelectionContext::copy_clone_conditions()`
 /// in `rustc_trait_selection`.
 mod impls {
-    use super::Clone;
-
     macro_rules! impl_clone {
         ($($t:ty)*) => {
             $(
diff --git a/library/core/src/convert/num.rs b/library/core/src/convert/num.rs
index b048b513592..08dc8f48dfe 100644
--- a/library/core/src/convert/num.rs
+++ b/library/core/src/convert/num.rs
@@ -1,4 +1,4 @@
-use super::{From, TryFrom};
+use super::TryFrom;
 use crate::num::TryFromIntError;
 
 mod private {
diff --git a/library/core/src/future/future.rs b/library/core/src/future/future.rs
index 8c7111cb3ff..71b9464efd2 100644
--- a/library/core/src/future/future.rs
+++ b/library/core/src/future/future.rs
@@ -1,6 +1,5 @@
 #![stable(feature = "futures_api", since = "1.36.0")]
 
-use crate::marker::Unpin;
 use crate::ops;
 use crate::pin::Pin;
 use crate::task::{Context, Poll};
diff --git a/library/core/src/iter/adapters/array_chunks.rs b/library/core/src/iter/adapters/array_chunks.rs
index 319af4408d7..946d0051cce 100644
--- a/library/core/src/iter/adapters/array_chunks.rs
+++ b/library/core/src/iter/adapters/array_chunks.rs
@@ -1,7 +1,7 @@
 use crate::array;
 use crate::iter::adapters::SourceIter;
 use crate::iter::{
-    ByRefSized, FusedIterator, InPlaceIterable, Iterator, TrustedFused, TrustedRandomAccessNoCoerce,
+    ByRefSized, FusedIterator, InPlaceIterable, TrustedFused, TrustedRandomAccessNoCoerce,
 };
 use crate::num::NonZeroUsize;
 use crate::ops::{ControlFlow, NeverShortCircuit, Try};
diff --git a/library/core/src/iter/adapters/chain.rs b/library/core/src/iter/adapters/chain.rs
index 26aa959e6da..c748336cd7f 100644
--- a/library/core/src/iter/adapters/chain.rs
+++ b/library/core/src/iter/adapters/chain.rs
@@ -1,4 +1,4 @@
-use crate::iter::{DoubleEndedIterator, FusedIterator, Iterator, TrustedLen};
+use crate::iter::{FusedIterator, TrustedLen};
 use crate::num::NonZeroUsize;
 use crate::ops::Try;
 
diff --git a/library/core/src/iter/adapters/flatten.rs b/library/core/src/iter/adapters/flatten.rs
index 09428350fd9..6122332da0d 100644
--- a/library/core/src/iter/adapters/flatten.rs
+++ b/library/core/src/iter/adapters/flatten.rs
@@ -1,7 +1,7 @@
 use crate::iter::adapters::SourceIter;
 use crate::iter::{
-    Cloned, Copied, DoubleEndedIterator, Filter, FilterMap, Fuse, FusedIterator, InPlaceIterable,
-    Iterator, Map, TrustedFused, TrustedLen,
+    Cloned, Copied, Filter, FilterMap, Fuse, FusedIterator, InPlaceIterable, Map, TrustedFused,
+    TrustedLen,
 };
 use crate::iter::{Once, OnceWith};
 use crate::num::NonZeroUsize;
diff --git a/library/core/src/iter/adapters/fuse.rs b/library/core/src/iter/adapters/fuse.rs
index 3234cade50d..462a7e87733 100644
--- a/library/core/src/iter/adapters/fuse.rs
+++ b/library/core/src/iter/adapters/fuse.rs
@@ -2,8 +2,7 @@ use crate::intrinsics;
 use crate::iter::adapters::zip::try_get_unchecked;
 use crate::iter::adapters::SourceIter;
 use crate::iter::{
-    DoubleEndedIterator, ExactSizeIterator, FusedIterator, TrustedFused, TrustedLen,
-    TrustedRandomAccess, TrustedRandomAccessNoCoerce,
+    FusedIterator, TrustedFused, TrustedLen, TrustedRandomAccess, TrustedRandomAccessNoCoerce,
 };
 use crate::ops::Try;
 
diff --git a/library/core/src/iter/adapters/map_windows.rs b/library/core/src/iter/adapters/map_windows.rs
index 3c0e80b2559..5f39b245834 100644
--- a/library/core/src/iter/adapters/map_windows.rs
+++ b/library/core/src/iter/adapters/map_windows.rs
@@ -1,6 +1,6 @@
 use crate::{
     fmt,
-    iter::{ExactSizeIterator, FusedIterator},
+    iter::FusedIterator,
     mem::{self, MaybeUninit},
     ptr,
 };
diff --git a/library/core/src/iter/adapters/mod.rs b/library/core/src/iter/adapters/mod.rs
index a691039c789..4037e2e2839 100644
--- a/library/core/src/iter/adapters/mod.rs
+++ b/library/core/src/iter/adapters/mod.rs
@@ -1,4 +1,4 @@
-use crate::iter::{InPlaceIterable, Iterator};
+use crate::iter::InPlaceIterable;
 use crate::num::NonZeroUsize;
 use crate::ops::{ChangeOutputType, ControlFlow, FromResidual, Residual, Try};
 
diff --git a/library/core/src/iter/adapters/zip.rs b/library/core/src/iter/adapters/zip.rs
index e3041519be7..b33400fab47 100644
--- a/library/core/src/iter/adapters/zip.rs
+++ b/library/core/src/iter/adapters/zip.rs
@@ -1,6 +1,6 @@
 use crate::cmp;
 use crate::fmt::{self, Debug};
-use crate::iter::{DoubleEndedIterator, ExactSizeIterator, FusedIterator, Iterator, TrustedFused};
+use crate::iter::{FusedIterator, TrustedFused};
 use crate::iter::{InPlaceIterable, SourceIter, TrustedLen, UncheckedIterator};
 use crate::num::NonZeroUsize;
 
diff --git a/library/core/src/mem/mod.rs b/library/core/src/mem/mod.rs
index bf10ada0176..c1687abb7cb 100644
--- a/library/core/src/mem/mod.rs
+++ b/library/core/src/mem/mod.rs
@@ -10,7 +10,7 @@ use crate::cmp;
 use crate::fmt;
 use crate::hash;
 use crate::intrinsics;
-use crate::marker::{Copy, DiscriminantKind, Sized};
+use crate::marker::DiscriminantKind;
 use crate::ptr;
 
 mod manually_drop;
diff --git a/library/core/src/ops/coroutine.rs b/library/core/src/ops/coroutine.rs
index 80e2903992e..e58c9068af8 100644
--- a/library/core/src/ops/coroutine.rs
+++ b/library/core/src/ops/coroutine.rs
@@ -1,4 +1,3 @@
-use crate::marker::Unpin;
 use crate::pin::Pin;
 
 /// The result of a coroutine resumption.
diff --git a/library/core/src/pin.rs b/library/core/src/pin.rs
index c3e774e1dab..7d8c881eab8 100644
--- a/library/core/src/pin.rs
+++ b/library/core/src/pin.rs
@@ -381,10 +381,9 @@
 
 #![stable(feature = "pin", since = "1.33.0")]
 
-use crate::cmp::{self, PartialEq, PartialOrd};
+use crate::cmp;
 use crate::fmt;
 use crate::hash::{Hash, Hasher};
-use crate::marker::{Sized, Unpin};
 use crate::ops::{CoerceUnsized, Deref, DerefMut, DispatchFromDyn, Receiver};
 
 /// A pinned pointer.
diff --git a/library/core/src/ptr/const_ptr.rs b/library/core/src/ptr/const_ptr.rs
index 2f47ca29ec5..bdf4ceeba4f 100644
--- a/library/core/src/ptr/const_ptr.rs
+++ b/library/core/src/ptr/const_ptr.rs
@@ -1,7 +1,7 @@
 use super::*;
-use crate::cmp::Ordering::{self, Equal, Greater, Less};
-use crate::intrinsics::{self, const_eval_select};
-use crate::mem::{self, SizedTypeProperties};
+use crate::cmp::Ordering::{Equal, Greater, Less};
+use crate::intrinsics::const_eval_select;
+use crate::mem::SizedTypeProperties;
 use crate::slice::{self, SliceIndex};
 
 impl<T: ?Sized> *const T {
diff --git a/library/core/src/ptr/mut_ptr.rs b/library/core/src/ptr/mut_ptr.rs
index 3aaae679a6f..b07403bd53f 100644
--- a/library/core/src/ptr/mut_ptr.rs
+++ b/library/core/src/ptr/mut_ptr.rs
@@ -1,6 +1,6 @@
 use super::*;
-use crate::cmp::Ordering::{self, Equal, Greater, Less};
-use crate::intrinsics::{self, const_eval_select};
+use crate::cmp::Ordering::{Equal, Greater, Less};
+use crate::intrinsics::const_eval_select;
 use crate::mem::SizedTypeProperties;
 use crate::slice::{self, SliceIndex};
 
diff --git a/library/core/src/ptr/non_null.rs b/library/core/src/ptr/non_null.rs
index c99fe36de6d..97fd7593ee1 100644
--- a/library/core/src/ptr/non_null.rs
+++ b/library/core/src/ptr/non_null.rs
@@ -1,5 +1,4 @@
 use crate::cmp::Ordering;
-use crate::convert::From;
 use crate::fmt;
 use crate::hash;
 use crate::intrinsics;
diff --git a/library/core/src/ptr/unique.rs b/library/core/src/ptr/unique.rs
index bf8b86677d5..067f1541e31 100644
--- a/library/core/src/ptr/unique.rs
+++ b/library/core/src/ptr/unique.rs
@@ -1,4 +1,3 @@
-use crate::convert::From;
 use crate::fmt;
 use crate::marker::{PhantomData, Unsize};
 use crate::ops::{CoerceUnsized, DispatchFromDyn};
diff --git a/library/core/src/slice/iter.rs b/library/core/src/slice/iter.rs
index 5e229bf5244..fc54ea23770 100644
--- a/library/core/src/slice/iter.rs
+++ b/library/core/src/slice/iter.rs
@@ -10,7 +10,7 @@ use crate::intrinsics::assume;
 use crate::iter::{
     FusedIterator, TrustedLen, TrustedRandomAccess, TrustedRandomAccessNoCoerce, UncheckedIterator,
 };
-use crate::marker::{PhantomData, Send, Sized, Sync};
+use crate::marker::PhantomData;
 use crate::mem::{self, SizedTypeProperties};
 use crate::num::NonZeroUsize;
 use crate::ptr::{self, invalid, invalid_mut, NonNull};
diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs
index dec9f194863..b14d9712794 100644
--- a/library/core/src/slice/mod.rs
+++ b/library/core/src/slice/mod.rs
@@ -9,16 +9,11 @@
 use crate::cmp::Ordering::{self, Equal, Greater, Less};
 use crate::fmt;
 use crate::intrinsics::exact_div;
-use crate::marker::Copy;
 use crate::mem::{self, SizedTypeProperties};
 use crate::num::NonZeroUsize;
-use crate::ops::{Bound, FnMut, OneSidedRange, Range, RangeBounds};
-use crate::option::Option;
-use crate::option::Option::{None, Some};
+use crate::ops::{Bound, OneSidedRange, Range, RangeBounds};
 use crate::panic::debug_assert_nounwind;
 use crate::ptr;
-use crate::result::Result;
-use crate::result::Result::{Err, Ok};
 use crate::simd::{self, Simd};
 use crate::slice;
 
diff --git a/library/core/src/task/poll.rs b/library/core/src/task/poll.rs
index 0a0f702f6fb..bfa1cf096e2 100644
--- a/library/core/src/task/poll.rs
+++ b/library/core/src/task/poll.rs
@@ -2,7 +2,6 @@
 
 use crate::convert;
 use crate::ops::{self, ControlFlow};
-use crate::result::Result;
 
 /// Indicates whether a value is available or if the current task has been
 /// scheduled to receive a wakeup instead.
diff --git a/library/core/src/task/wake.rs b/library/core/src/task/wake.rs
index 817e39942c0..1a11291e86b 100644
--- a/library/core/src/task/wake.rs
+++ b/library/core/src/task/wake.rs
@@ -1,7 +1,7 @@
 #![stable(feature = "futures_api", since = "1.36.0")]
 
 use crate::fmt;
-use crate::marker::{PhantomData, Unpin};
+use crate::marker::PhantomData;
 use crate::ptr;
 
 /// A `RawWaker` allows the implementor of a task executor to create a [`Waker`]
diff --git a/library/core/tests/array.rs b/library/core/tests/array.rs
index 81da75d32a1..3656eecca50 100644
--- a/library/core/tests/array.rs
+++ b/library/core/tests/array.rs
@@ -1,5 +1,4 @@
 use core::{array, assert_eq};
-use core::convert::TryFrom;
 use core::num::NonZeroUsize;
 use core::sync::atomic::{AtomicUsize, Ordering};
 
diff --git a/library/core/tests/cell.rs b/library/core/tests/cell.rs
index e084f867943..71b8eb29600 100644
--- a/library/core/tests/cell.rs
+++ b/library/core/tests/cell.rs
@@ -1,6 +1,4 @@
 use core::cell::*;
-use core::default::Default;
-use std::mem::drop;
 
 #[test]
 fn smoketest_unsafe_cell() {
diff --git a/library/core/tests/char.rs b/library/core/tests/char.rs
index 85ba51c9228..6422387e956 100644
--- a/library/core/tests/char.rs
+++ b/library/core/tests/char.rs
@@ -1,4 +1,3 @@
-use std::convert::TryFrom;
 use std::str::FromStr;
 use std::{char, str};
 
diff --git a/library/core/tests/hash/mod.rs b/library/core/tests/hash/mod.rs
index 5268f32c031..addc255de4a 100644
--- a/library/core/tests/hash/mod.rs
+++ b/library/core/tests/hash/mod.rs
@@ -1,6 +1,5 @@
 mod sip;
 
-use std::default::Default;
 use std::hash::{BuildHasher, Hash, Hasher};
 use std::ptr;
 use std::rc::Rc;
diff --git a/library/core/tests/iter/adapters/array_chunks.rs b/library/core/tests/iter/adapters/array_chunks.rs
index ef4a7e53bdd..fb19a519f63 100644
--- a/library/core/tests/iter/adapters/array_chunks.rs
+++ b/library/core/tests/iter/adapters/array_chunks.rs
@@ -1,5 +1,4 @@
-use core::cell::Cell;
-use core::iter::{self, Iterator};
+use core::iter::{self};
 
 use super::*;
 
diff --git a/library/core/tests/iter/mod.rs b/library/core/tests/iter/mod.rs
index 770b6f7601f..5b2769d0469 100644
--- a/library/core/tests/iter/mod.rs
+++ b/library/core/tests/iter/mod.rs
@@ -21,7 +21,6 @@ mod sources;
 mod traits;
 
 use core::cell::Cell;
-use core::convert::TryFrom;
 use core::iter::*;
 
 pub fn is_trusted_len<I: TrustedLen>(_: I) {}
diff --git a/library/core/tests/nonzero.rs b/library/core/tests/nonzero.rs
index 007f8442533..8873d26880c 100644
--- a/library/core/tests/nonzero.rs
+++ b/library/core/tests/nonzero.rs
@@ -1,9 +1,8 @@
-use core::convert::TryFrom;
 use core::num::{
     IntErrorKind, NonZeroI128, NonZeroI16, NonZeroI32, NonZeroI64, NonZeroI8, NonZeroIsize,
     NonZeroU128, NonZeroU16, NonZeroU32, NonZeroU64, NonZeroU8, NonZeroUsize,
 };
-use core::option::Option::{self, None, Some};
+use core::option::Option::None;
 use std::mem::size_of;
 
 #[test]
diff --git a/library/core/tests/num/mod.rs b/library/core/tests/num/mod.rs
index 3f3659ba837..863da9b18a2 100644
--- a/library/core/tests/num/mod.rs
+++ b/library/core/tests/num/mod.rs
@@ -1,11 +1,6 @@
-use core::cmp::PartialEq;
-use core::convert::{TryFrom, TryInto};
 use core::fmt::Debug;
-use core::marker::Copy;
 use core::num::{can_not_overflow, IntErrorKind, ParseIntError, TryFromIntError};
 use core::ops::{Add, Div, Mul, Rem, Sub};
-use core::option::Option;
-use core::option::Option::None;
 use core::str::FromStr;
 
 #[macro_use]
diff --git a/library/core/tests/option.rs b/library/core/tests/option.rs
index 5dc012bab4a..00a308b29d2 100644
--- a/library/core/tests/option.rs
+++ b/library/core/tests/option.rs
@@ -1,5 +1,4 @@
 use core::cell::Cell;
-use core::clone::Clone;
 use core::mem;
 use core::ops::DerefMut;
 use core::option::*;
diff --git a/library/core/tests/slice.rs b/library/core/tests/slice.rs
index 666452ead3f..33a30339856 100644
--- a/library/core/tests/slice.rs
+++ b/library/core/tests/slice.rs
@@ -2,7 +2,6 @@ use core::cell::Cell;
 use core::cmp::Ordering;
 use core::mem::MaybeUninit;
 use core::num::NonZeroUsize;
-use core::result::Result::{Err, Ok};
 use core::slice;
 
 #[test]
diff --git a/library/std/src/backtrace.rs b/library/std/src/backtrace.rs
index 7fcf2ee358c..9638f491987 100644
--- a/library/std/src/backtrace.rs
+++ b/library/std/src/backtrace.rs
@@ -96,7 +96,6 @@ use crate::panic::UnwindSafe;
 use crate::sync::atomic::{AtomicUsize, Ordering::Relaxed};
 use crate::sync::LazyLock;
 use crate::sys_common::backtrace::{lock, output_filename, set_image_base};
-use crate::vec::Vec;
 
 /// A captured OS thread stack backtrace.
 ///
diff --git a/library/std/src/backtrace/tests.rs b/library/std/src/backtrace/tests.rs
index 73543a3af54..174d62813bd 100644
--- a/library/std/src/backtrace/tests.rs
+++ b/library/std/src/backtrace/tests.rs
@@ -1,5 +1,5 @@
 use super::*;
-use crate::panic::{RefUnwindSafe, UnwindSafe};
+use crate::panic::RefUnwindSafe;
 
 fn generate_fake_frames() -> Vec<BacktraceFrame> {
     vec![
diff --git a/library/std/src/env/tests.rs b/library/std/src/env/tests.rs
index 55869229581..fc7aee29733 100644
--- a/library/std/src/env/tests.rs
+++ b/library/std/src/env/tests.rs
@@ -1,7 +1,5 @@
 use super::*;
 
-use crate::path::Path;
-
 #[test]
 #[cfg_attr(any(target_os = "emscripten", target_env = "sgx"), ignore)]
 fn test_self_exe_path() {
diff --git a/library/std/src/ffi/os_str/tests.rs b/library/std/src/ffi/os_str/tests.rs
index 2765398d3e6..60cde376d32 100644
--- a/library/std/src/ffi/os_str/tests.rs
+++ b/library/std/src/ffi/os_str/tests.rs
@@ -1,8 +1,4 @@
 use super::*;
-use crate::sys_common::{AsInner, IntoInner};
-
-use crate::rc::Rc;
-use crate::sync::Arc;
 
 #[test]
 fn test_os_string_with_capacity() {
diff --git a/library/std/src/io/error/repr_bitpacked.rs b/library/std/src/io/error/repr_bitpacked.rs
index 6e7366b3635..db175659770 100644
--- a/library/std/src/io/error/repr_bitpacked.rs
+++ b/library/std/src/io/error/repr_bitpacked.rs
@@ -103,7 +103,6 @@
 //! the time.
 
 use super::{Custom, ErrorData, ErrorKind, RawOsError, SimpleMessage};
-use alloc::boxed::Box;
 use core::marker::PhantomData;
 use core::mem::{align_of, size_of};
 use core::ptr::{self, NonNull};
diff --git a/library/std/src/io/error/repr_unpacked.rs b/library/std/src/io/error/repr_unpacked.rs
index 093fde33757..dc8a95577c9 100644
--- a/library/std/src/io/error/repr_unpacked.rs
+++ b/library/std/src/io/error/repr_unpacked.rs
@@ -3,7 +3,6 @@
 //! would have no benefit.
 
 use super::{Custom, ErrorData, ErrorKind, RawOsError, SimpleMessage};
-use alloc::boxed::Box;
 
 type Inner = ErrorData<Box<Custom>>;
 
diff --git a/library/std/src/net/tcp/tests.rs b/library/std/src/net/tcp/tests.rs
index db367cfa0f7..b24b851a645 100644
--- a/library/std/src/net/tcp/tests.rs
+++ b/library/std/src/net/tcp/tests.rs
@@ -1,6 +1,6 @@
 use crate::fmt;
 use crate::io::prelude::*;
-use crate::io::{BorrowedBuf, ErrorKind, IoSlice, IoSliceMut};
+use crate::io::{BorrowedBuf, IoSlice, IoSliceMut};
 use crate::mem::MaybeUninit;
 use crate::net::test::{next_test_ip4, next_test_ip6};
 use crate::net::*;
diff --git a/library/std/src/net/udp/tests.rs b/library/std/src/net/udp/tests.rs
index 892fe2ba8ba..0cf99366452 100644
--- a/library/std/src/net/udp/tests.rs
+++ b/library/std/src/net/udp/tests.rs
@@ -1,4 +1,3 @@
-use crate::io::ErrorKind;
 use crate::net::test::{next_test_ip4, next_test_ip6};
 use crate::net::*;
 use crate::sync::mpsc::channel;
diff --git a/library/std/src/path/tests.rs b/library/std/src/path/tests.rs
index dbc0f7d9df3..fde6ed4f0c0 100644
--- a/library/std/src/path/tests.rs
+++ b/library/std/src/path/tests.rs
@@ -1,9 +1,7 @@
 use super::*;
 
 use crate::collections::{BTreeSet, HashSet};
-use crate::hash::{DefaultHasher, Hasher};
-use crate::rc::Rc;
-use crate::sync::Arc;
+use crate::hash::DefaultHasher;
 use core::hint::black_box;
 
 #[allow(unknown_lints, unused_macro_rules)]
diff --git a/library/std/src/sync/mpsc/sync_tests.rs b/library/std/src/sync/mpsc/sync_tests.rs
index 632709fd98d..945de280f40 100644
--- a/library/std/src/sync/mpsc/sync_tests.rs
+++ b/library/std/src/sync/mpsc/sync_tests.rs
@@ -3,7 +3,6 @@ use crate::env;
 use crate::rc::Rc;
 use crate::sync::mpmc::SendTimeoutError;
 use crate::thread;
-use crate::time::Duration;
 
 pub fn stress_factor() -> usize {
     match env::var("RUST_TEST_STRESS") {
diff --git a/library/std/src/sync/mpsc/tests.rs b/library/std/src/sync/mpsc/tests.rs
index 1e52a4a705c..ac1a804cf9c 100644
--- a/library/std/src/sync/mpsc/tests.rs
+++ b/library/std/src/sync/mpsc/tests.rs
@@ -1,7 +1,6 @@
 use super::*;
 use crate::env;
 use crate::thread;
-use crate::time::{Duration, Instant};
 
 pub fn stress_factor() -> usize {
     match env::var("RUST_TEST_STRESS") {
diff --git a/library/std/src/sys_common/wtf8/tests.rs b/library/std/src/sys_common/wtf8/tests.rs
index a07bbe6d7e4..28a426648e5 100644
--- a/library/std/src/sys_common/wtf8/tests.rs
+++ b/library/std/src/sys_common/wtf8/tests.rs
@@ -1,5 +1,4 @@
 use super::*;
-use crate::borrow::Cow;
 
 #[test]
 fn code_point_from_u32() {
diff --git a/library/test/src/term/terminfo/parm/tests.rs b/library/test/src/term/terminfo/parm/tests.rs
index c738f3ba04f..e785d84f3fd 100644
--- a/library/test/src/term/terminfo/parm/tests.rs
+++ b/library/test/src/term/terminfo/parm/tests.rs
@@ -1,7 +1,5 @@
 use super::*;
 
-use std::result::Result::Ok;
-
 #[test]
 fn test_basic_setabf() {
     let s = b"\\E[48;5;%p1%dm";
diff --git a/library/test/src/tests.rs b/library/test/src/tests.rs
index 4ef18b14f4c..43a906ad298 100644
--- a/library/test/src/tests.rs
+++ b/library/test/src/tests.rs
@@ -1,34 +1,17 @@
 use super::*;
 
 use crate::{
-    bench::Bencher,
     console::OutputLocation,
     formatters::PrettyFormatter,
-    options::OutputFormat,
     test::{
-        filter_tests,
         parse_opts,
-        run_test,
-        DynTestFn,
-        DynTestName,
         MetricMap,
-        RunIgnored,
-        RunStrategy,
-        ShouldPanic,
-        StaticTestName,
-        TestDesc,
-        TestDescAndFn,
-        TestOpts,
-        TrIgnored,
-        TrOk,
         // FIXME (introduced by #65251)
         // ShouldPanic, StaticTestName, TestDesc, TestDescAndFn, TestOpts, TestTimeOptions,
         // TestType, TrFailedMsg, TrIgnored, TrOk,
     },
     time::{TestTimeOptions, TimeThreshold},
 };
-use std::sync::mpsc::channel;
-use std::time::Duration;
 
 impl TestOpts {
     fn new() -> TestOpts {
diff --git a/src/librustdoc/clean/auto_trait.rs b/src/librustdoc/clean/auto_trait.rs
index 007c5e113b7..e692f4ef72e 100644
--- a/src/librustdoc/clean/auto_trait.rs
+++ b/src/librustdoc/clean/auto_trait.rs
@@ -1,9 +1,7 @@
-use rustc_data_structures::fx::FxHashSet;
 use rustc_hir as hir;
 use rustc_hir::lang_items::LangItem;
-use rustc_middle::ty::{self, Region, RegionVid, TypeFoldable};
+use rustc_middle::ty::{Region, RegionVid, TypeFoldable};
 use rustc_trait_selection::traits::auto_trait::{self, AutoTraitResult};
-use thin_vec::ThinVec;
 
 use std::fmt::Debug;
 
diff --git a/src/librustdoc/clean/cfg/tests.rs b/src/librustdoc/clean/cfg/tests.rs
index bb62660e194..20bcf1abf41 100644
--- a/src/librustdoc/clean/cfg/tests.rs
+++ b/src/librustdoc/clean/cfg/tests.rs
@@ -1,8 +1,8 @@
 use super::*;
 
-use rustc_ast::{LitKind, MetaItemLit, Path, StrStyle};
+use rustc_ast::{MetaItemLit, Path, StrStyle};
 use rustc_span::create_default_session_globals_then;
-use rustc_span::symbol::{kw, Ident, Symbol};
+use rustc_span::symbol::{kw, Ident};
 use rustc_span::DUMMY_SP;
 use thin_vec::thin_vec;
 
diff --git a/src/librustdoc/clean/types.rs b/src/librustdoc/clean/types.rs
index 7a5cf803137..0a14404d689 100644
--- a/src/librustdoc/clean/types.rs
+++ b/src/librustdoc/clean/types.rs
@@ -31,7 +31,7 @@ use rustc_resolve::rustdoc::{
 use rustc_session::Session;
 use rustc_span::hygiene::MacroKind;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
-use rustc_span::{self, FileName, Loc, DUMMY_SP};
+use rustc_span::{FileName, Loc, DUMMY_SP};
 use rustc_target::abi::VariantIdx;
 use rustc_target::spec::abi::Abi;
 
diff --git a/src/librustdoc/clean/types/tests.rs b/src/librustdoc/clean/types/tests.rs
index ee7c0068eb4..4befce07170 100644
--- a/src/librustdoc/clean/types/tests.rs
+++ b/src/librustdoc/clean/types/tests.rs
@@ -1,8 +1,7 @@
 use super::*;
 
-use rustc_resolve::rustdoc::{unindent_doc_fragments, DocFragment, DocFragmentKind};
-use rustc_span::symbol::Symbol;
-use rustc_span::{create_default_session_globals_then, DUMMY_SP};
+use rustc_resolve::rustdoc::{unindent_doc_fragments, DocFragmentKind};
+use rustc_span::create_default_session_globals_then;
 
 fn create_doc_fragment(s: &str) -> Vec<DocFragment> {
     vec![DocFragment {
diff --git a/src/librustdoc/docfs.rs b/src/librustdoc/docfs.rs
index 82c1a503924..1f7abdfc315 100644
--- a/src/librustdoc/docfs.rs
+++ b/src/librustdoc/docfs.rs
@@ -12,7 +12,6 @@ use std::cmp::max;
 use std::fs;
 use std::io;
 use std::path::{Path, PathBuf};
-use std::string::ToString;
 use std::sync::mpsc::Sender;
 use std::thread::available_parallelism;
 use threadpool::ThreadPool;
diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index 58599de76ea..34350c2ed3a 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -45,7 +45,6 @@ use std::iter::Peekable;
 use std::path::PathBuf;
 use std::rc::Rc;
 use std::str;
-use std::string::ToString;
 
 use askama::Template;
 use rustc_attr::{ConstStability, DeprecatedSince, Deprecation, StabilityLevel, StableSince};
diff --git a/src/tools/clippy/clippy_lints/src/escape.rs b/src/tools/clippy/clippy_lints/src/escape.rs
index ae1e69a4f23..3452f98c5aa 100644
--- a/src/tools/clippy/clippy_lints/src/escape.rs
+++ b/src/tools/clippy/clippy_lints/src/escape.rs
@@ -1,5 +1,5 @@
 use clippy_utils::diagnostics::span_lint_hir;
-use rustc_hir::{self, intravisit, AssocItemKind, Body, FnDecl, HirId, HirIdSet, Impl, ItemKind, Node, Pat, PatKind};
+use rustc_hir::{intravisit, AssocItemKind, Body, FnDecl, HirId, HirIdSet, Impl, ItemKind, Node, Pat, PatKind};
 use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, PlaceBase, PlaceWithHirId};
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
diff --git a/src/tools/clippy/clippy_lints/src/loops/manual_memcpy.rs b/src/tools/clippy/clippy_lints/src/loops/manual_memcpy.rs
index 40d56240b9d..fda6c9749d4 100644
--- a/src/tools/clippy/clippy_lints/src/loops/manual_memcpy.rs
+++ b/src/tools/clippy/clippy_lints/src/loops/manual_memcpy.rs
@@ -12,7 +12,6 @@ use rustc_lint::LateContext;
 use rustc_middle::ty::{self, Ty};
 use rustc_span::symbol::sym;
 use std::fmt::Display;
-use std::iter::Iterator;
 
 /// Checks for `for` loops that sequentially copy items from one slice-like
 /// object to another.
diff --git a/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs b/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs
index e2be861a708..28abecd0429 100644
--- a/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs
+++ b/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs
@@ -13,7 +13,7 @@ use rustc_lint::LateContext;
 use rustc_middle::middle::region;
 use rustc_middle::ty::{self, Ty};
 use rustc_span::symbol::{sym, Symbol};
-use std::iter::{self, Iterator};
+use std::iter::{self};
 use std::mem;
 
 /// Checks for looping over a range and then indexing a sequence with it.
diff --git a/src/tools/clippy/clippy_lints/src/loops/never_loop.rs b/src/tools/clippy/clippy_lints/src/loops/never_loop.rs
index cc054cb4669..62bc663191f 100644
--- a/src/tools/clippy/clippy_lints/src/loops/never_loop.rs
+++ b/src/tools/clippy/clippy_lints/src/loops/never_loop.rs
@@ -8,7 +8,7 @@ use rustc_errors::Applicability;
 use rustc_hir::{Block, Destination, Expr, ExprKind, HirId, InlineAsmOperand, Pat, Stmt, StmtKind};
 use rustc_lint::LateContext;
 use rustc_span::{sym, Span};
-use std::iter::{once, Iterator};
+use std::iter::once;
 
 pub(super) fn check<'tcx>(
     cx: &LateContext<'tcx>,
diff --git a/src/tools/clippy/clippy_lints/src/loops/same_item_push.rs b/src/tools/clippy/clippy_lints/src/loops/same_item_push.rs
index 15e11fd386c..f4eaf649f77 100644
--- a/src/tools/clippy/clippy_lints/src/loops/same_item_push.rs
+++ b/src/tools/clippy/clippy_lints/src/loops/same_item_push.rs
@@ -11,7 +11,6 @@ use rustc_hir::{BindingAnnotation, Block, Expr, ExprKind, HirId, Mutability, Nod
 use rustc_lint::LateContext;
 use rustc_span::symbol::sym;
 use rustc_span::SyntaxContext;
-use std::iter::Iterator;
 
 /// Detects for loop pushing the same item into a Vec
 pub(super) fn check<'tcx>(
diff --git a/src/tools/clippy/clippy_lints/src/loops/utils.rs b/src/tools/clippy/clippy_lints/src/loops/utils.rs
index 38fdca573c6..e685274adb8 100644
--- a/src/tools/clippy/clippy_lints/src/loops/utils.rs
+++ b/src/tools/clippy/clippy_lints/src/loops/utils.rs
@@ -9,7 +9,6 @@ use rustc_middle::hir::nested_filter;
 use rustc_middle::ty::{self, Ty};
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{sym, Symbol};
-use std::iter::Iterator;
 
 #[derive(Debug, PartialEq, Eq)]
 enum IncrementVisitorVarState {
diff --git a/src/tools/clippy/clippy_lints/src/methods/option_map_unwrap_or.rs b/src/tools/clippy/clippy_lints/src/methods/option_map_unwrap_or.rs
index 575c2d8f157..826c3de1db5 100644
--- a/src/tools/clippy/clippy_lints/src/methods/option_map_unwrap_or.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/option_map_unwrap_or.rs
@@ -6,7 +6,7 @@ use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::Applicability;
 use rustc_hir::def::Res;
 use rustc_hir::intravisit::{walk_path, Visitor};
-use rustc_hir::{self, ExprKind, HirId, Node, PatKind, Path, QPath};
+use rustc_hir::{ExprKind, HirId, Node, PatKind, Path, QPath};
 use rustc_lint::LateContext;
 use rustc_middle::hir::nested_filter;
 use rustc_span::{sym, Span};
diff --git a/src/tools/clippy/clippy_lints/src/missing_inline.rs b/src/tools/clippy/clippy_lints/src/missing_inline.rs
index 07bcbfc4ff4..7393b39c8f6 100644
--- a/src/tools/clippy/clippy_lints/src/missing_inline.rs
+++ b/src/tools/clippy/clippy_lints/src/missing_inline.rs
@@ -1,7 +1,7 @@
 use clippy_utils::diagnostics::span_lint;
 use rustc_ast::ast;
 use rustc_hir as hir;
-use rustc_lint::{self, LateContext, LateLintPass, LintContext};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_session::declare_lint_pass;
 use rustc_span::{sym, Span};
 
diff --git a/src/tools/miri/src/borrow_tracker/stacked_borrows/diagnostics.rs b/src/tools/miri/src/borrow_tracker/stacked_borrows/diagnostics.rs
index 1a11879fa90..b31f51e5a5c 100644
--- a/src/tools/miri/src/borrow_tracker/stacked_borrows/diagnostics.rs
+++ b/src/tools/miri/src/borrow_tracker/stacked_borrows/diagnostics.rs
@@ -2,12 +2,11 @@ use smallvec::SmallVec;
 use std::fmt;
 
 use rustc_data_structures::fx::FxHashSet;
-use rustc_middle::mir::interpret::{alloc_range, AllocId, AllocRange, InterpError};
 use rustc_span::{Span, SpanData};
 use rustc_target::abi::Size;
 
 use crate::borrow_tracker::{
-    stacked_borrows::Permission, AccessKind, GlobalStateInner, ProtectorKind,
+    AccessKind, GlobalStateInner, ProtectorKind,
 };
 use crate::*;
 
diff --git a/src/tools/miri/src/borrow_tracker/stacked_borrows/mod.rs b/src/tools/miri/src/borrow_tracker/stacked_borrows/mod.rs
index 1df2b1b8391..345c71f75b3 100644
--- a/src/tools/miri/src/borrow_tracker/stacked_borrows/mod.rs
+++ b/src/tools/miri/src/borrow_tracker/stacked_borrows/mod.rs
@@ -18,8 +18,7 @@ use rustc_target::abi::{Abi, Size};
 
 use crate::borrow_tracker::{
     stacked_borrows::diagnostics::{AllocHistory, DiagnosticCx, DiagnosticCxBuilder},
-    AccessKind, GlobalStateInner, ProtectorKind, RetagFields,
-};
+    AccessKind, GlobalStateInner, ProtectorKind,};
 use crate::*;
 
 use diagnostics::{RetagCause, RetagInfo};
diff --git a/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs b/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs
index e902939290a..84e4e0f2222 100644
--- a/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs
+++ b/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs
@@ -3,7 +3,7 @@ use log::trace;
 use rustc_target::abi::{Abi, Size};
 
 use crate::borrow_tracker::{
-    AccessKind, GlobalState, GlobalStateInner, ProtectorKind, RetagFields,
+    AccessKind, GlobalState, GlobalStateInner, ProtectorKind,
 };
 use rustc_middle::{
     mir::{Mutability, RetagKind},
diff --git a/src/tools/miri/src/borrow_tracker/tree_borrows/tree.rs b/src/tools/miri/src/borrow_tracker/tree_borrows/tree.rs
index 6801397b2ce..778a544544b 100644
--- a/src/tools/miri/src/borrow_tracker/tree_borrows/tree.rs
+++ b/src/tools/miri/src/borrow_tracker/tree_borrows/tree.rs
@@ -14,7 +14,6 @@ use std::fmt;
 
 use smallvec::SmallVec;
 
-use rustc_const_eval::interpret::InterpResult;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_span::Span;
 use rustc_target::abi::Size;
diff --git a/src/tools/miri/src/concurrency/weak_memory.rs b/src/tools/miri/src/concurrency/weak_memory.rs
index 39e89ce7faa..9ebb64afd35 100644
--- a/src/tools/miri/src/concurrency/weak_memory.rs
+++ b/src/tools/miri/src/concurrency/weak_memory.rs
@@ -82,7 +82,6 @@ use std::{
     collections::VecDeque,
 };
 
-use rustc_const_eval::interpret::{alloc_range, AllocRange, InterpResult, MPlaceTy, Scalar};
 use rustc_data_structures::fx::FxHashMap;
 
 use crate::*;
diff --git a/src/tools/miri/src/eval.rs b/src/tools/miri/src/eval.rs
index 875a78974fa..6013c0bd341 100644
--- a/src/tools/miri/src/eval.rs
+++ b/src/tools/miri/src/eval.rs
@@ -10,7 +10,6 @@ use std::thread;
 use log::info;
 use rustc_middle::ty::Ty;
 
-use crate::borrow_tracker::RetagFields;
 use crate::concurrency::thread::TlsAllocAction;
 use crate::diagnostics::report_leaks;
 use rustc_data_structures::fx::FxHashSet;
diff --git a/src/tools/miri/src/shims/env.rs b/src/tools/miri/src/shims/env.rs
index 9e19f720211..9e8239cdbac 100644
--- a/src/tools/miri/src/shims/env.rs
+++ b/src/tools/miri/src/shims/env.rs
@@ -3,7 +3,6 @@ use std::ffi::{OsStr, OsString};
 use std::io::ErrorKind;
 use std::mem;
 
-use rustc_const_eval::interpret::Pointer;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::ty::layout::LayoutOf;
 use rustc_middle::ty::Ty;
diff --git a/src/tools/miri/src/shims/unix/fs.rs b/src/tools/miri/src/shims/unix/fs.rs
index be30627cf0c..1402f07dd38 100644
--- a/src/tools/miri/src/shims/unix/fs.rs
+++ b/src/tools/miri/src/shims/unix/fs.rs
@@ -1,7 +1,6 @@
 use std::any::Any;
 use std::borrow::Cow;
 use std::collections::BTreeMap;
-use std::convert::TryInto;
 use std::fs::{
     read_dir, remove_dir, remove_file, rename, DirBuilder, File, FileType, OpenOptions, ReadDir,
 };
diff --git a/src/tools/miri/src/shims/unix/linux/sync.rs b/src/tools/miri/src/shims/unix/linux/sync.rs
index 10e06226b3f..66105391c47 100644
--- a/src/tools/miri/src/shims/unix/linux/sync.rs
+++ b/src/tools/miri/src/shims/unix/linux/sync.rs
@@ -1,6 +1,6 @@
 use std::time::SystemTime;
 
-use crate::concurrency::thread::{MachineCallback, Time};
+use crate::concurrency::thread::MachineCallback;
 use crate::*;
 
 /// Implementation of the SYS_futex syscall.
diff --git a/src/tools/miri/src/shims/unix/sync.rs b/src/tools/miri/src/shims/unix/sync.rs
index 45b47450b7b..054e9719b34 100644
--- a/src/tools/miri/src/shims/unix/sync.rs
+++ b/src/tools/miri/src/shims/unix/sync.rs
@@ -1,7 +1,7 @@
 use std::time::SystemTime;
 
 use crate::concurrency::sync::CondvarLock;
-use crate::concurrency::thread::{MachineCallback, Time};
+use crate::concurrency::thread::MachineCallback;
 use crate::*;
 
 // pthread_mutexattr_t is either 4 or 8 bytes, depending on the platform.
diff --git a/src/tools/miri/tests/pass-dep/shims/libc-fs.rs b/src/tools/miri/tests/pass-dep/shims/libc-fs.rs
index 697970a0885..fafeb9e0558 100644
--- a/src/tools/miri/tests/pass-dep/shims/libc-fs.rs
+++ b/src/tools/miri/tests/pass-dep/shims/libc-fs.rs
@@ -4,7 +4,6 @@
 #![feature(io_error_more)]
 #![feature(io_error_uncategorized)]
 
-use std::convert::TryInto;
 use std::ffi::CString;
 use std::fs::{canonicalize, remove_dir_all, remove_file, File};
 use std::io::{Error, ErrorKind, Write};
diff --git a/src/tools/miri/tests/pass/arrays.rs b/src/tools/miri/tests/pass/arrays.rs
index 9589ffa1724..61b44453e9b 100644
--- a/src/tools/miri/tests/pass/arrays.rs
+++ b/src/tools/miri/tests/pass/arrays.rs
@@ -1,5 +1,3 @@
-use std::convert::TryFrom;
-
 fn empty_array() -> [u16; 0] {
     []
 }
diff --git a/src/tools/miri/tests/pass/binary-heap.rs b/src/tools/miri/tests/pass/binary-heap.rs
index 278038d8ad3..e85e56e1b79 100644
--- a/src/tools/miri/tests/pass/binary-heap.rs
+++ b/src/tools/miri/tests/pass/binary-heap.rs
@@ -1,5 +1,4 @@
 use std::collections::BinaryHeap;
-use std::iter::Iterator;
 
 fn zero_sized_push() {
     const N: usize = 8;
diff --git a/src/tools/miri/tests/pass/enum-nullable-const-null-with-fields.rs b/src/tools/miri/tests/pass/enum-nullable-const-null-with-fields.rs
index 8385cc5d880..c42cd87f9a1 100644
--- a/src/tools/miri/tests/pass/enum-nullable-const-null-with-fields.rs
+++ b/src/tools/miri/tests/pass/enum-nullable-const-null-with-fields.rs
@@ -1,5 +1,3 @@
-use std::result::Result;
-use std::result::Result::Ok;
 
 static C: Result<(), Box<isize>> = Ok(());
 
diff --git a/src/tools/rust-analyzer/crates/stdx/src/anymap.rs b/src/tools/rust-analyzer/crates/stdx/src/anymap.rs
index fd44e6c6d0f..7dba002c6ec 100644
--- a/src/tools/rust-analyzer/crates/stdx/src/anymap.rs
+++ b/src/tools/rust-analyzer/crates/stdx/src/anymap.rs
@@ -17,7 +17,6 @@
 
 #![warn(missing_docs, unused_results)]
 
-use core::convert::TryInto;
 use core::hash::Hasher;
 
 /// A hasher designed to eke a little more speed out, given `TypeId`’s known characteristics.
diff --git a/src/tools/rustfmt/src/comment.rs b/src/tools/rustfmt/src/comment.rs
index 7da0f79bd09..f7cd7cefb3d 100644
--- a/src/tools/rustfmt/src/comment.rs
+++ b/src/tools/rustfmt/src/comment.rs
@@ -1,6 +1,6 @@
 // Formatting and tools for comments.
 
-use std::{self, borrow::Cow, iter};
+use std::{borrow::Cow, iter};
 
 use itertools::{multipeek, MultiPeek};
 use lazy_static::lazy_static;
@@ -1847,7 +1847,6 @@ fn remove_comment_header(comment: &str) -> &str {
 #[cfg(test)]
 mod test {
     use super::*;
-    use crate::shape::{Indent, Shape};
 
     #[test]
     fn char_classes() {
diff --git a/src/tools/rustfmt/src/config/file_lines.rs b/src/tools/rustfmt/src/config/file_lines.rs
index e33fe9bb283..224864393d3 100644
--- a/src/tools/rustfmt/src/config/file_lines.rs
+++ b/src/tools/rustfmt/src/config/file_lines.rs
@@ -6,7 +6,7 @@ use std::path::PathBuf;
 use std::{cmp, fmt, iter, str};
 
 use rustc_data_structures::sync::Lrc;
-use rustc_span::{self, SourceFile};
+use rustc_span::SourceFile;
 use serde::{ser, Deserialize, Deserializer, Serialize, Serializer};
 use serde_json as json;
 use thiserror::Error;
diff --git a/src/tools/rustfmt/src/config/mod.rs b/src/tools/rustfmt/src/config/mod.rs
index 7538b26522d..9d454137b2c 100644
--- a/src/tools/rustfmt/src/config/mod.rs
+++ b/src/tools/rustfmt/src/config/mod.rs
@@ -1,5 +1,4 @@
 use std::cell::Cell;
-use std::default::Default;
 use std::fs::File;
 use std::io::{Error, ErrorKind, Read};
 use std::path::{Path, PathBuf};
@@ -1017,7 +1016,6 @@ make_backup = false
     #[cfg(test)]
     mod partially_unstable_option {
         use super::mock::{Config, PartiallyUnstableOption};
-        use super::*;
 
         /// From the command line, we can override with a stable variant.
         #[test]
diff --git a/src/tools/rustfmt/src/emitter/checkstyle.rs b/src/tools/rustfmt/src/emitter/checkstyle.rs
index 56d6a0ed681..2a4a9dfce8e 100644
--- a/src/tools/rustfmt/src/emitter/checkstyle.rs
+++ b/src/tools/rustfmt/src/emitter/checkstyle.rs
@@ -1,7 +1,6 @@
 use self::xml::XmlEscaped;
 use super::*;
 use crate::rustfmt_diff::{make_diff, DiffLine, Mismatch};
-use std::io::{self, Write};
 
 mod xml;
 
diff --git a/src/tools/rustfmt/src/emitter/diff.rs b/src/tools/rustfmt/src/emitter/diff.rs
index 764cd136e01..0af19a7d0b2 100644
--- a/src/tools/rustfmt/src/emitter/diff.rs
+++ b/src/tools/rustfmt/src/emitter/diff.rs
@@ -51,8 +51,6 @@ impl Emitter for DiffEmitter {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::config::Config;
-    use crate::FileName;
     use std::path::PathBuf;
 
     #[test]
diff --git a/src/tools/rustfmt/src/emitter/json.rs b/src/tools/rustfmt/src/emitter/json.rs
index 5594196bed9..f47c3260a02 100644
--- a/src/tools/rustfmt/src/emitter/json.rs
+++ b/src/tools/rustfmt/src/emitter/json.rs
@@ -2,7 +2,6 @@ use super::*;
 use crate::rustfmt_diff::{make_diff, DiffLine, Mismatch};
 use serde::Serialize;
 use serde_json::to_string as to_json_string;
-use std::io::{self, Write};
 
 #[derive(Debug, Default)]
 pub(crate) struct JsonEmitter {
@@ -106,7 +105,6 @@ impl JsonEmitter {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::FileName;
     use std::path::PathBuf;
 
     #[test]
diff --git a/src/tools/rustfmt/src/emitter/modified_lines.rs b/src/tools/rustfmt/src/emitter/modified_lines.rs
index 94ff570a8a9..81f0a31b974 100644
--- a/src/tools/rustfmt/src/emitter/modified_lines.rs
+++ b/src/tools/rustfmt/src/emitter/modified_lines.rs
@@ -1,6 +1,5 @@
 use super::*;
 use crate::rustfmt_diff::{make_diff, ModifiedLines};
-use std::io::Write;
 
 #[derive(Debug, Default)]
 pub(crate) struct ModifiedLinesEmitter;
diff --git a/src/tools/rustfmt/src/emitter/stdout.rs b/src/tools/rustfmt/src/emitter/stdout.rs
index 0bbc7332dfe..0b635a28bf2 100644
--- a/src/tools/rustfmt/src/emitter/stdout.rs
+++ b/src/tools/rustfmt/src/emitter/stdout.rs
@@ -1,6 +1,5 @@
 use super::*;
 use crate::config::Verbosity;
-use std::io::Write;
 
 #[derive(Debug)]
 pub(crate) struct StdoutEmitter {
diff --git a/src/tools/rustfmt/src/ignore_path.rs b/src/tools/rustfmt/src/ignore_path.rs
index d955949496a..7b5697bec3e 100644
--- a/src/tools/rustfmt/src/ignore_path.rs
+++ b/src/tools/rustfmt/src/ignore_path.rs
@@ -1,4 +1,4 @@
-use ignore::{self, gitignore};
+use ignore::gitignore;
 
 use crate::config::{FileName, IgnoreList};
 
diff --git a/src/tools/rustfmt/src/imports.rs b/src/tools/rustfmt/src/imports.rs
index f8e7fa62890..09f6e752338 100644
--- a/src/tools/rustfmt/src/imports.rs
+++ b/src/tools/rustfmt/src/imports.rs
@@ -1102,7 +1102,6 @@ enum SharedPrefix {
 #[cfg(test)]
 mod test {
     use super::*;
-    use rustc_span::DUMMY_SP;
 
     // Parse the path part of an import. This parser is not robust and is only
     // suitable for use in a test harness.
diff --git a/src/tools/rustfmt/src/reorder.rs b/src/tools/rustfmt/src/reorder.rs
index 3bddf4c1b6a..3e14f9f1272 100644
--- a/src/tools/rustfmt/src/reorder.rs
+++ b/src/tools/rustfmt/src/reorder.rs
@@ -6,7 +6,7 @@
 
 // FIXME(#2455): Reorder trait items.
 
-use std::cmp::{Ord, Ordering};
+use std::cmp::Ordering;
 
 use rustc_ast::{ast, attr};
 use rustc_span::{symbol::sym, Span};
diff --git a/src/tools/rustfmt/src/types.rs b/src/tools/rustfmt/src/types.rs
index 8ca27150371..a5a4244903c 100644
--- a/src/tools/rustfmt/src/types.rs
+++ b/src/tools/rustfmt/src/types.rs
@@ -1,4 +1,3 @@
-use std::iter::ExactSizeIterator;
 use std::ops::Deref;
 
 use rustc_ast::ast::{self, FnRetTy, Mutability, Term};
diff --git a/tests/ui-fulldeps/pprust-expr-roundtrip.rs b/tests/ui-fulldeps/pprust-expr-roundtrip.rs
index fe5333643ed..24c4543c20c 100644
--- a/tests/ui-fulldeps/pprust-expr-roundtrip.rs
+++ b/tests/ui-fulldeps/pprust-expr-roundtrip.rs
@@ -32,7 +32,7 @@ extern crate thin_vec;
 #[allow(unused_extern_crates)]
 extern crate rustc_driver;
 
-use rustc_ast::mut_visit::{self, visit_clobber, MutVisitor};
+use rustc_ast::mut_visit::{visit_clobber, MutVisitor};
 use rustc_ast::ptr::P;
 use rustc_ast::*;
 use rustc_ast_pretty::pprust;
diff --git a/tests/ui/bare-fn-implements-fn-mut.rs b/tests/ui/bare-fn-implements-fn-mut.rs
index dfead48893e..d6ecd6b654b 100644
--- a/tests/ui/bare-fn-implements-fn-mut.rs
+++ b/tests/ui/bare-fn-implements-fn-mut.rs
@@ -1,7 +1,5 @@
 // run-pass
 
-use std::ops::FnMut;
-
 fn call_f<F:FnMut()>(mut f: F) {
     f();
 }
diff --git a/tests/ui/box/alloc-unstable.rs b/tests/ui/box/alloc-unstable.rs
index 66388d0d512..640cadcc8e3 100644
--- a/tests/ui/box/alloc-unstable.rs
+++ b/tests/ui/box/alloc-unstable.rs
@@ -1,8 +1,5 @@
 // run-pass
 #![feature(allocator_api)]
-
-use std::boxed::Box;
-
 fn main() {
     let _boxed: Box<u32, _> = Box::new(10);
 }
diff --git a/tests/ui/box/into-boxed-slice.rs b/tests/ui/box/into-boxed-slice.rs
index 61b3d915253..86866ac2f7e 100644
--- a/tests/ui/box/into-boxed-slice.rs
+++ b/tests/ui/box/into-boxed-slice.rs
@@ -1,7 +1,5 @@
 // run-pass
 #![feature(box_into_boxed_slice)]
-
-use std::boxed::Box;
 fn main() {
     assert_eq!(Box::into_boxed_slice(Box::new(5u8)), Box::new([5u8]) as Box<[u8]>);
     assert_eq!(Box::into_boxed_slice(Box::new([25u8])), Box::new([[25u8]]) as Box<[[u8; 1]]>);
diff --git a/tests/ui/box/new-box-syntax.rs b/tests/ui/box/new-box-syntax.rs
index c56e1dd4625..e3b1550d60b 100644
--- a/tests/ui/box/new-box-syntax.rs
+++ b/tests/ui/box/new-box-syntax.rs
@@ -8,8 +8,6 @@
 
 // Tests that the new `box` syntax works with unique pointers.
 
-use std::boxed::Box;
-
 struct Structure {
     x: isize,
     y: isize,
diff --git a/tests/ui/box/unit/unique-kinds.rs b/tests/ui/box/unit/unique-kinds.rs
index f02d0b50764..1ef09d7195a 100644
--- a/tests/ui/box/unit/unique-kinds.rs
+++ b/tests/ui/box/unit/unique-kinds.rs
@@ -1,6 +1,5 @@
 // run-pass
 
-use std::cmp::PartialEq;
 use std::fmt::Debug;
 
 fn sendable() {
diff --git a/tests/ui/cleanup-rvalue-for-scope.rs b/tests/ui/cleanup-rvalue-for-scope.rs
index b6582c01fba..38a41f3b8d7 100644
--- a/tests/ui/cleanup-rvalue-for-scope.rs
+++ b/tests/ui/cleanup-rvalue-for-scope.rs
@@ -5,9 +5,6 @@
 #![allow(unused_variables)]
 // Test that the lifetime of rvalues in for loops is extended
 // to the for loop itself.
-
-use std::ops::Drop;
-
 static mut FLAGS: u64 = 0;
 
 struct Box<T> { f: T }
diff --git a/tests/ui/cleanup-rvalue-scopes.rs b/tests/ui/cleanup-rvalue-scopes.rs
index b80f95b79f9..56340e515b9 100644
--- a/tests/ui/cleanup-rvalue-scopes.rs
+++ b/tests/ui/cleanup-rvalue-scopes.rs
@@ -8,8 +8,6 @@
 
 #![feature(box_patterns)]
 
-use std::ops::Drop;
-
 static mut FLAGS: u64 = 0;
 
 struct Box<T> { f: T }
diff --git a/tests/ui/coherence/coherence-negative-impls-safe-rpass.rs b/tests/ui/coherence/coherence-negative-impls-safe-rpass.rs
index b87e162aca0..d5306d59ed5 100644
--- a/tests/ui/coherence/coherence-negative-impls-safe-rpass.rs
+++ b/tests/ui/coherence/coherence-negative-impls-safe-rpass.rs
@@ -4,8 +4,6 @@
 
 #![feature(negative_impls)]
 
-use std::marker::Send;
-
 struct TestType;
 
 impl !Send for TestType {}
diff --git a/tests/ui/coherence/coherence-where-clause.rs b/tests/ui/coherence/coherence-where-clause.rs
index 5c40def86bb..cd9a423f4ec 100644
--- a/tests/ui/coherence/coherence-where-clause.rs
+++ b/tests/ui/coherence/coherence-where-clause.rs
@@ -1,8 +1,6 @@
 // run-pass
 
 use std::fmt::Debug;
-use std::default::Default;
-
 trait MyTrait {
     fn get(&self) -> Self;
 }
diff --git a/tests/ui/consts/const-block.rs b/tests/ui/consts/const-block.rs
index ec99c70f6e0..40c7a7a1da9 100644
--- a/tests/ui/consts/const-block.rs
+++ b/tests/ui/consts/const-block.rs
@@ -3,8 +3,6 @@
 #![allow(dead_code)]
 #![allow(unused_unsafe)]
 
-use std::marker::Sync;
-
 struct Foo {
     a: usize,
     b: *const ()
diff --git a/tests/ui/coroutine/control-flow.rs b/tests/ui/coroutine/control-flow.rs
index 709b135b2ee..0cb37524a6c 100644
--- a/tests/ui/coroutine/control-flow.rs
+++ b/tests/ui/coroutine/control-flow.rs
@@ -5,7 +5,6 @@
 
 #![feature(coroutines, coroutine_trait)]
 
-use std::marker::Unpin;
 use std::ops::{CoroutineState, Coroutine};
 use std::pin::Pin;
 
diff --git a/tests/ui/coroutine/discriminant.rs b/tests/ui/coroutine/discriminant.rs
index 73bdd9c8671..0cdeb6dd678 100644
--- a/tests/ui/coroutine/discriminant.rs
+++ b/tests/ui/coroutine/discriminant.rs
@@ -6,7 +6,7 @@
 #![feature(coroutines, coroutine_trait, core_intrinsics, discriminant_kind)]
 
 use std::intrinsics::discriminant_value;
-use std::marker::{DiscriminantKind, Unpin};
+use std::marker::DiscriminantKind;
 use std::mem::size_of_val;
 use std::{cmp, ops::*};
 
diff --git a/tests/ui/coroutine/iterator-count.rs b/tests/ui/coroutine/iterator-count.rs
index 322e56f8a8b..b7628c44ddc 100644
--- a/tests/ui/coroutine/iterator-count.rs
+++ b/tests/ui/coroutine/iterator-count.rs
@@ -2,7 +2,6 @@
 
 #![feature(coroutines, coroutine_trait)]
 
-use std::marker::Unpin;
 use std::ops::{Coroutine, CoroutineState};
 use std::pin::Pin;
 
diff --git a/tests/ui/coroutine/non-static-is-unpin.rs b/tests/ui/coroutine/non-static-is-unpin.rs
index d6ded53ae5a..d77fe659f08 100644
--- a/tests/ui/coroutine/non-static-is-unpin.rs
+++ b/tests/ui/coroutine/non-static-is-unpin.rs
@@ -5,7 +5,7 @@
 #![feature(coroutines, coroutine_trait)]
 #![allow(dropping_copy_types)]
 
-use std::marker::{PhantomPinned, Unpin};
+use std::marker::PhantomPinned;
 
 fn assert_unpin<G: Unpin>(_: G) {
 }
diff --git a/tests/ui/coroutine/smoke-resume-args.rs b/tests/ui/coroutine/smoke-resume-args.rs
index a801989859e..752b21ba087 100644
--- a/tests/ui/coroutine/smoke-resume-args.rs
+++ b/tests/ui/coroutine/smoke-resume-args.rs
@@ -6,7 +6,6 @@
 #![feature(coroutines, coroutine_trait)]
 
 use std::fmt::Debug;
-use std::marker::Unpin;
 use std::ops::{
     Coroutine,
     CoroutineState::{self, *},
diff --git a/tests/ui/extern/issue-13655.rs b/tests/ui/extern/issue-13655.rs
index 6dd1847995f..a47b5183f2b 100644
--- a/tests/ui/extern/issue-13655.rs
+++ b/tests/ui/extern/issue-13655.rs
@@ -1,7 +1,5 @@
 // run-pass
 #![feature(fn_traits, unboxed_closures)]
-use std::ops::Fn;
-
 struct Foo<T>(T);
 
 impl<T: Copy> Fn<()> for Foo<T> {
diff --git a/tests/ui/for-loop-while/while-prelude-drop.rs b/tests/ui/for-loop-while/while-prelude-drop.rs
index 196b9daf6ec..947a70e1dd2 100644
--- a/tests/ui/for-loop-while/while-prelude-drop.rs
+++ b/tests/ui/for-loop-while/while-prelude-drop.rs
@@ -1,8 +1,5 @@
 // run-pass
 #![allow(non_camel_case_types)]
-
-use std::string::String;
-
 #[derive(PartialEq)]
 enum t { a, b(String), }
 
diff --git a/tests/ui/issues/issue-20847.rs b/tests/ui/issues/issue-20847.rs
index 0cd7edf89db..03e632263e6 100644
--- a/tests/ui/issues/issue-20847.rs
+++ b/tests/ui/issues/issue-20847.rs
@@ -1,8 +1,6 @@
 // run-pass
 #![feature(fn_traits)]
 
-use std::ops::Fn;
-
 fn say(x: u32, y: u32) {
     println!("{} {}", x, y);
 }
diff --git a/tests/ui/issues/issue-5554.rs b/tests/ui/issues/issue-5554.rs
index 7737536f43d..afe333ed709 100644
--- a/tests/ui/issues/issue-5554.rs
+++ b/tests/ui/issues/issue-5554.rs
@@ -2,7 +2,6 @@
 #![allow(dead_code)]
 // pretty-expanded FIXME #23616
 
-use std::default::Default;
 
 pub struct X<T> {
     a: T,
diff --git a/tests/ui/issues/issue-8783.rs b/tests/ui/issues/issue-8783.rs
index 4eb49c82161..cfffd9eb018 100644
--- a/tests/ui/issues/issue-8783.rs
+++ b/tests/ui/issues/issue-8783.rs
@@ -2,8 +2,6 @@
 #![allow(unused_variables)]
 // pretty-expanded FIXME #23616
 
-use std::default::Default;
-
 struct X { pub x: usize }
 impl Default for X {
     fn default() -> X {
diff --git a/tests/ui/moves/move-out-of-field.rs b/tests/ui/moves/move-out-of-field.rs
index 9f697db4f79..4166d8dc8e9 100644
--- a/tests/ui/moves/move-out-of-field.rs
+++ b/tests/ui/moves/move-out-of-field.rs
@@ -1,7 +1,5 @@
 // run-pass
 
-use std::string::String;
-
 struct StringBuffer {
     s: String,
 }
diff --git a/tests/ui/overloaded/overloaded-calls-param-vtables.rs b/tests/ui/overloaded/overloaded-calls-param-vtables.rs
index fde1ad20f7d..74ee1c17614 100644
--- a/tests/ui/overloaded/overloaded-calls-param-vtables.rs
+++ b/tests/ui/overloaded/overloaded-calls-param-vtables.rs
@@ -6,7 +6,6 @@
 #![feature(unboxed_closures, fn_traits)]
 
 use std::marker::PhantomData;
-use std::ops::Fn;
 use std::ops::Add;
 
 struct G<A>(PhantomData<A>);
diff --git a/tests/ui/overloaded/overloaded-calls-simple.rs b/tests/ui/overloaded/overloaded-calls-simple.rs
index 41318360799..8fed18b8e29 100644
--- a/tests/ui/overloaded/overloaded-calls-simple.rs
+++ b/tests/ui/overloaded/overloaded-calls-simple.rs
@@ -2,8 +2,6 @@
 
 #![feature(lang_items, unboxed_closures, fn_traits)]
 
-use std::ops::{Fn, FnMut, FnOnce};
-
 struct S1 {
     x: i32,
     y: i32,
diff --git a/tests/ui/overloaded/overloaded-calls-zero-args.rs b/tests/ui/overloaded/overloaded-calls-zero-args.rs
index 69ca88619b8..b1237306790 100644
--- a/tests/ui/overloaded/overloaded-calls-zero-args.rs
+++ b/tests/ui/overloaded/overloaded-calls-zero-args.rs
@@ -2,8 +2,6 @@
 
 #![feature(unboxed_closures, fn_traits)]
 
-use std::ops::FnMut;
-
 struct S {
     x: i32,
     y: i32,
diff --git a/tests/ui/overloaded/overloaded-deref-count.rs b/tests/ui/overloaded/overloaded-deref-count.rs
index e2f1e10b5c8..d2482b12500 100644
--- a/tests/ui/overloaded/overloaded-deref-count.rs
+++ b/tests/ui/overloaded/overloaded-deref-count.rs
@@ -2,7 +2,6 @@
 
 use std::cell::Cell;
 use std::ops::{Deref, DerefMut};
-use std::vec::Vec;
 
 struct DerefCounter<T> {
     count_imm: Cell<usize>,
diff --git a/tests/ui/overloaded/overloaded-deref.rs b/tests/ui/overloaded/overloaded-deref.rs
index 73d8232a322..b08d8f3f767 100644
--- a/tests/ui/overloaded/overloaded-deref.rs
+++ b/tests/ui/overloaded/overloaded-deref.rs
@@ -1,7 +1,6 @@
 // run-pass
 use std::cell::RefCell;
 use std::rc::Rc;
-use std::string::String;
 
 #[derive(PartialEq, Debug)]
 struct Point {
diff --git a/tests/ui/regions/regions-lifetime-static-items-enclosing-scopes.rs b/tests/ui/regions/regions-lifetime-static-items-enclosing-scopes.rs
index b6a89e29ecc..2c455fc3563 100644
--- a/tests/ui/regions/regions-lifetime-static-items-enclosing-scopes.rs
+++ b/tests/ui/regions/regions-lifetime-static-items-enclosing-scopes.rs
@@ -3,9 +3,6 @@
 // This test verifies that temporary lifetime is correctly computed
 // for static objects in enclosing scopes.
 
-
-use std::cmp::PartialEq;
-
 fn f<T:PartialEq+std::fmt::Debug>(o: &mut Option<T>) {
     assert_eq!(*o, None);
 }
diff --git a/tests/ui/specialization/specialization-translate-projections.rs b/tests/ui/specialization/specialization-translate-projections.rs
index 92ea9e2b85d..a9753376135 100644
--- a/tests/ui/specialization/specialization-translate-projections.rs
+++ b/tests/ui/specialization/specialization-translate-projections.rs
@@ -5,7 +5,6 @@
 
 #![feature(specialization)] //~ WARN the feature `specialization` is incomplete
 
-use std::convert::Into;
 
 trait Trait {
     fn to_u8(&self) -> u8;
diff --git a/tests/ui/stdlib-unit-tests/istr.rs b/tests/ui/stdlib-unit-tests/istr.rs
index dca6d40d59a..219b47789b8 100644
--- a/tests/ui/stdlib-unit-tests/istr.rs
+++ b/tests/ui/stdlib-unit-tests/istr.rs
@@ -1,7 +1,5 @@
 // run-pass
 
-use std::string::String;
-
 fn test_stack_assign() {
     let s: String = "a".to_string();
     println!("{}", s.clone());
diff --git a/tests/ui/stdlib-unit-tests/minmax-stability-issue-23687.rs b/tests/ui/stdlib-unit-tests/minmax-stability-issue-23687.rs
index 9100bfbde95..7fbffb8fa98 100644
--- a/tests/ui/stdlib-unit-tests/minmax-stability-issue-23687.rs
+++ b/tests/ui/stdlib-unit-tests/minmax-stability-issue-23687.rs
@@ -1,7 +1,7 @@
 // run-pass
 
 use std::fmt::Debug;
-use std::cmp::{self, PartialOrd, Ordering};
+use std::cmp::{self, Ordering};
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 struct Foo {
diff --git a/tests/ui/structs-enums/class-cast-to-trait-cross-crate-2.rs b/tests/ui/structs-enums/class-cast-to-trait-cross-crate-2.rs
index f870096fdd4..989f0a275f7 100644
--- a/tests/ui/structs-enums/class-cast-to-trait-cross-crate-2.rs
+++ b/tests/ui/structs-enums/class-cast-to-trait-cross-crate-2.rs
@@ -3,7 +3,6 @@
 
 extern crate cci_class_cast;
 
-use std::string::ToString;
 use cci_class_cast::kitty::cat;
 
 fn print_out(thing: Box<dyn ToString>, expected: String) {
diff --git a/tests/ui/structs-enums/enum-nullable-const-null-with-fields.rs b/tests/ui/structs-enums/enum-nullable-const-null-with-fields.rs
index ae267e7988e..1d52d44d169 100644
--- a/tests/ui/structs-enums/enum-nullable-const-null-with-fields.rs
+++ b/tests/ui/structs-enums/enum-nullable-const-null-with-fields.rs
@@ -1,8 +1,5 @@
 // run-pass
 
-use std::result::Result;
-use std::result::Result::Ok;
-
 static C: Result<(), Box<isize>> = Ok(());
 
 // This is because of yet another bad assertion (ICE) about the null side of a nullable enum.
diff --git a/tests/ui/suggestions/derive-clone-for-eq.fixed b/tests/ui/suggestions/derive-clone-for-eq.fixed
index f07784d53b3..a74487019ad 100644
--- a/tests/ui/suggestions/derive-clone-for-eq.fixed
+++ b/tests/ui/suggestions/derive-clone-for-eq.fixed
@@ -1,8 +1,6 @@
 // run-rustfix
 // https://github.com/rust-lang/rust/issues/79076
 
-use std::cmp::PartialEq;
-
 #[derive(Clone, Eq)] //~ ERROR [E0277]
 pub struct Struct<T: std::clone::Clone>(T);
 
diff --git a/tests/ui/suggestions/derive-clone-for-eq.rs b/tests/ui/suggestions/derive-clone-for-eq.rs
index 15c0d4659fb..99956ed9879 100644
--- a/tests/ui/suggestions/derive-clone-for-eq.rs
+++ b/tests/ui/suggestions/derive-clone-for-eq.rs
@@ -1,8 +1,6 @@
 // run-rustfix
 // https://github.com/rust-lang/rust/issues/79076
 
-use std::cmp::PartialEq;
-
 #[derive(Clone, Eq)] //~ ERROR [E0277]
 pub struct Struct<T>(T);
 
diff --git a/tests/ui/suggestions/derive-clone-for-eq.stderr b/tests/ui/suggestions/derive-clone-for-eq.stderr
index eb95f729d1e..680890e880c 100644
--- a/tests/ui/suggestions/derive-clone-for-eq.stderr
+++ b/tests/ui/suggestions/derive-clone-for-eq.stderr
@@ -1,11 +1,11 @@
 error[E0277]: the trait bound `T: Clone` is not satisfied
-  --> $DIR/derive-clone-for-eq.rs:6:17
+  --> $DIR/derive-clone-for-eq.rs:4:17
    |
 LL | #[derive(Clone, Eq)]
    |                 ^^ the trait `Clone` is not implemented for `T`
    |
 note: required for `Struct<T>` to implement `PartialEq`
-  --> $DIR/derive-clone-for-eq.rs:9:19
+  --> $DIR/derive-clone-for-eq.rs:7:19
    |
 LL | impl<T: Clone, U> PartialEq<U> for Struct<T>
    |         -----     ^^^^^^^^^^^^     ^^^^^^^^^
diff --git a/tests/ui/traits/inheritance/num0.rs b/tests/ui/traits/inheritance/num0.rs
index cee52542d38..c9c73ee00e6 100644
--- a/tests/ui/traits/inheritance/num0.rs
+++ b/tests/ui/traits/inheritance/num0.rs
@@ -4,8 +4,6 @@
 
 // pretty-expanded FIXME #23616
 
-use std::cmp::PartialOrd;
-
 pub trait NumCast: Sized {
     fn from(i: i32) -> Option<Self>;
 }
diff --git a/tests/ui/traits/inheritance/overloading-simple.rs b/tests/ui/traits/inheritance/overloading-simple.rs
index c306aa2cda0..800d7bc6b1f 100644
--- a/tests/ui/traits/inheritance/overloading-simple.rs
+++ b/tests/ui/traits/inheritance/overloading-simple.rs
@@ -1,6 +1,5 @@
 // run-pass
 #![allow(dead_code)]
-use std::cmp::PartialEq;
 
 trait MyNum : PartialEq { }
 
diff --git a/tests/ui/traits/inheritance/overloading.rs b/tests/ui/traits/inheritance/overloading.rs
index 083643e821f..f126847da09 100644
--- a/tests/ui/traits/inheritance/overloading.rs
+++ b/tests/ui/traits/inheritance/overloading.rs
@@ -1,5 +1,4 @@
 // run-pass
-use std::cmp::PartialEq;
 use std::ops::{Add, Sub, Mul};
 
 trait MyNum : Add<Output=Self> + Sub<Output=Self> + Mul<Output=Self> + PartialEq + Clone { }
diff --git a/tests/ui/traits/issue-22019.rs b/tests/ui/traits/issue-22019.rs
index 1a887f0f39f..605fee510b1 100644
--- a/tests/ui/traits/issue-22019.rs
+++ b/tests/ui/traits/issue-22019.rs
@@ -8,8 +8,6 @@
 #![allow(missing_copy_implementations)]
 #![allow(unused_variables)]
 
-use std::borrow::ToOwned;
-
 pub struct CFGNode;
 
 pub type Node<'a> = &'a CFGNode;
diff --git a/tests/ui/traits/multidispatch2.rs b/tests/ui/traits/multidispatch2.rs
index 20608aabb3b..21aa13fd487 100644
--- a/tests/ui/traits/multidispatch2.rs
+++ b/tests/ui/traits/multidispatch2.rs
@@ -1,7 +1,6 @@
 // run-pass
 
 use std::fmt::Debug;
-use std::default::Default;
 
 trait MyTrait<T> {
     fn get(&self) -> T;
diff --git a/tests/ui/traits/negative-impls/negated-auto-traits-rpass.rs b/tests/ui/traits/negative-impls/negated-auto-traits-rpass.rs
index a1042f8310a..0bc611c26ca 100644
--- a/tests/ui/traits/negative-impls/negated-auto-traits-rpass.rs
+++ b/tests/ui/traits/negative-impls/negated-auto-traits-rpass.rs
@@ -2,8 +2,6 @@
 #![allow(unused_variables)]
 #![feature(negative_impls)]
 
-use std::marker::Send;
-
 pub struct WaitToken;
 impl !Send for WaitToken {}
 
diff --git a/tests/ui/traits/wf-object/reverse-order.rs b/tests/ui/traits/wf-object/reverse-order.rs
index 4f676cbe338..74b2ef48533 100644
--- a/tests/ui/traits/wf-object/reverse-order.rs
+++ b/tests/ui/traits/wf-object/reverse-order.rs
@@ -2,8 +2,6 @@
 
 // Ensure that `dyn $($AutoTrait)+ ObjSafe` is well-formed.
 
-use std::marker::Unpin;
-
 // Some arbitrary object-safe trait:
 trait Obj {}
 
diff --git a/tests/ui/ufcs/ufcs-polymorphic-paths.rs b/tests/ui/ufcs/ufcs-polymorphic-paths.rs
index a14ebd6a41f..71b9de8184c 100644
--- a/tests/ui/ufcs/ufcs-polymorphic-paths.rs
+++ b/tests/ui/ufcs/ufcs-polymorphic-paths.rs
@@ -1,7 +1,6 @@
 // run-pass
 
-use std::borrow::{Cow, ToOwned};
-use std::default::Default;
+use std::borrow::Cow;
 use std::iter::FromIterator;
 use std::ops::Add;
 use std::option::IntoIter as OptionIter;
diff --git a/tests/ui/unboxed-closures/unboxed-closures-boxed.rs b/tests/ui/unboxed-closures/unboxed-closures-boxed.rs
index 3f550fd0425..53f0523da70 100644
--- a/tests/ui/unboxed-closures/unboxed-closures-boxed.rs
+++ b/tests/ui/unboxed-closures/unboxed-closures-boxed.rs
@@ -1,6 +1,5 @@
 // run-pass
 
-use std::ops::FnMut;
 
  fn make_adder(x: i32) -> Box<dyn FnMut(i32)->i32+'static> {
     Box::new(move |y: i32| -> i32 { x + y }) as
diff --git a/tests/ui/unboxed-closures/unboxed-closures-call-sugar-autoderef.rs b/tests/ui/unboxed-closures/unboxed-closures-call-sugar-autoderef.rs
index 9b8a3f4098c..8a40c1d4785 100644
--- a/tests/ui/unboxed-closures/unboxed-closures-call-sugar-autoderef.rs
+++ b/tests/ui/unboxed-closures/unboxed-closures-call-sugar-autoderef.rs
@@ -1,8 +1,6 @@
 // run-pass
 // Test that the call operator autoderefs when calling a bounded type parameter.
 
-use std::ops::FnMut;
-
 fn call_with_2<F>(x: &mut F) -> isize
     where F : FnMut(isize) -> isize
 {
diff --git a/tests/ui/unboxed-closures/unboxed-closures-call-sugar-object-autoderef.rs b/tests/ui/unboxed-closures/unboxed-closures-call-sugar-object-autoderef.rs
index d47ceea0f4f..2433f0757aa 100644
--- a/tests/ui/unboxed-closures/unboxed-closures-call-sugar-object-autoderef.rs
+++ b/tests/ui/unboxed-closures/unboxed-closures-call-sugar-object-autoderef.rs
@@ -1,8 +1,6 @@
 // run-pass
 // Test that the call operator autoderefs when calling to an object type.
 
-use std::ops::FnMut;
-
 fn make_adder(x: isize) -> Box<dyn FnMut(isize)->isize + 'static> {
     Box::new(move |y| { x + y })
 }
diff --git a/tests/ui/unboxed-closures/unboxed-closures-call-sugar-object.rs b/tests/ui/unboxed-closures/unboxed-closures-call-sugar-object.rs
index f77733d106d..b27d6104959 100644
--- a/tests/ui/unboxed-closures/unboxed-closures-call-sugar-object.rs
+++ b/tests/ui/unboxed-closures/unboxed-closures-call-sugar-object.rs
@@ -1,6 +1,4 @@
 // run-pass
-use std::ops::FnMut;
-
 fn make_adder(x: isize) -> Box<dyn FnMut(isize)->isize + 'static> {
     Box::new(move |y| { x + y })
 }
diff --git a/tests/ui/unboxed-closures/unboxed-closures-extern-fn.rs b/tests/ui/unboxed-closures/unboxed-closures-extern-fn.rs
index 677cd259a4e..d07e871b10d 100644
--- a/tests/ui/unboxed-closures/unboxed-closures-extern-fn.rs
+++ b/tests/ui/unboxed-closures/unboxed-closures-extern-fn.rs
@@ -1,7 +1,6 @@
 // run-pass
 // Checks that extern fn pointers implement the full range of Fn traits.
 
-use std::ops::{Fn,FnMut,FnOnce};
 
 fn square(x: isize) -> isize { x * x }
 
diff --git a/tests/ui/unboxed-closures/unboxed-closures-fn-as-fnmut-and-fnonce.rs b/tests/ui/unboxed-closures/unboxed-closures-fn-as-fnmut-and-fnonce.rs
index 851f3d2fe9b..db1bea0e115 100644
--- a/tests/ui/unboxed-closures/unboxed-closures-fn-as-fnmut-and-fnonce.rs
+++ b/tests/ui/unboxed-closures/unboxed-closures-fn-as-fnmut-and-fnonce.rs
@@ -4,8 +4,6 @@
 
 #![feature(unboxed_closures, fn_traits)]
 
-use std::ops::{Fn,FnMut,FnOnce};
-
 struct S;
 
 impl Fn<(i32,)> for S {
diff --git a/tests/ui/unboxed-closures/unboxed-closures-generic.rs b/tests/ui/unboxed-closures/unboxed-closures-generic.rs
index 740b8b2a72f..524e756e69b 100644
--- a/tests/ui/unboxed-closures/unboxed-closures-generic.rs
+++ b/tests/ui/unboxed-closures/unboxed-closures-generic.rs
@@ -1,6 +1,4 @@
 // run-pass
-use std::ops::FnMut;
-
 fn call_it<F:FnMut(i32,i32)->i32>(y: i32, mut f: F) -> i32 {
     f(2, y)
 }
diff --git a/tests/ui/zero-sized/zero-sized-binary-heap-push.rs b/tests/ui/zero-sized/zero-sized-binary-heap-push.rs
index 6553c5adbe7..14cf6c2036b 100644
--- a/tests/ui/zero-sized/zero-sized-binary-heap-push.rs
+++ b/tests/ui/zero-sized/zero-sized-binary-heap-push.rs
@@ -1,7 +1,6 @@
 // run-pass
 #![allow(unused_variables)]
 use std::collections::BinaryHeap;
-use std::iter::Iterator;
 
 fn main() {
     const N: usize = 8;
diff --git a/tests/ui/zero-sized/zero-sized-linkedlist-push.rs b/tests/ui/zero-sized/zero-sized-linkedlist-push.rs
index 03724085f5f..301f03110b7 100644
--- a/tests/ui/zero-sized/zero-sized-linkedlist-push.rs
+++ b/tests/ui/zero-sized/zero-sized-linkedlist-push.rs
@@ -1,6 +1,5 @@
 // run-pass
 use std::collections::LinkedList;
-use std::iter::Iterator;
 
 fn main() {
     const N: usize = 8;