Rollup of 6 pull requests

compiler/rustc_driver_impl/src/lib.rs

@@ -28,7 +28,7 @@ use rustc_errors::{
     markdown, ColorConfig, DiagCtxt, ErrCode, ErrorGuaranteed, FatalError, PResult,
 };
 use rustc_feature::find_gated_cfg;
-use rustc_interface::util::{self, collect_crate_types, get_codegen_backend};
+use rustc_interface::util::{self, get_codegen_backend};
 use rustc_interface::{interface, Queries};
 use rustc_lint::unerased_lint_store;
 use rustc_metadata::creader::MetadataLoader;
@@ -37,6 +37,7 @@ use rustc_session::config::{nightly_options, CG_OPTIONS, Z_OPTIONS};
 use rustc_session::config::{ErrorOutputType, Input, OutFileName, OutputType};
 use rustc_session::getopts::{self, Matches};
 use rustc_session::lint::{Lint, LintId};
+use rustc_session::output::collect_crate_types;
 use rustc_session::{config, filesearch, EarlyDiagCtxt, Session};
 use rustc_span::def_id::LOCAL_CRATE;
 use rustc_span::source_map::FileLoader;

compiler/rustc_incremental/src/persist/fs.rs

@@ -110,8 +110,9 @@ use rustc_data_structures::unord::{UnordMap, UnordSet};
 use rustc_data_structures::{base_n, flock};
 use rustc_errors::ErrorGuaranteed;
 use rustc_fs_util::{link_or_copy, try_canonicalize, LinkOrCopy};
+use rustc_session::config::CrateType;
+use rustc_session::output::{collect_crate_types, find_crate_name};
 use rustc_session::{Session, StableCrateId};
-use rustc_span::Symbol;
 
 use std::fs as std_fs;
 use std::io::{self, ErrorKind};
@@ -205,11 +206,7 @@ pub fn in_incr_comp_dir(incr_comp_session_dir: &Path, file_name: &str) -> PathBu
 /// The garbage collection will take care of it.
 ///
 /// [`rustc_interface::queries::dep_graph`]: ../../rustc_interface/struct.Queries.html#structfield.dep_graph
-pub(crate) fn prepare_session_directory(
-    sess: &Session,
-    crate_name: Symbol,
-    stable_crate_id: StableCrateId,
-) -> Result<(), ErrorGuaranteed> {
+pub(crate) fn prepare_session_directory(sess: &Session) -> Result<(), ErrorGuaranteed> {
     if sess.opts.incremental.is_none() {
         return Ok(());
     }
@@ -219,7 +216,7 @@ pub(crate) fn prepare_session_directory(
     debug!("prepare_session_directory");
 
     // {incr-comp-dir}/{crate-name-and-disambiguator}
-    let crate_dir = crate_path(sess, crate_name, stable_crate_id);
+    let crate_dir = crate_path(sess);
     debug!("crate-dir: {}", crate_dir.display());
     create_dir(sess, &crate_dir, "crate")?;
 
@@ -604,9 +601,18 @@ fn string_to_timestamp(s: &str) -> Result<SystemTime, &'static str> {
     Ok(UNIX_EPOCH + duration)
 }
 
-fn crate_path(sess: &Session, crate_name: Symbol, stable_crate_id: StableCrateId) -> PathBuf {
+fn crate_path(sess: &Session) -> PathBuf {
     let incr_dir = sess.opts.incremental.as_ref().unwrap().clone();
 
+    let crate_name = find_crate_name(sess, &[]);
+    let crate_types = collect_crate_types(sess, &[]);
+    let stable_crate_id = StableCrateId::new(
+        crate_name,
+        crate_types.contains(&CrateType::Executable),
+        sess.opts.cg.metadata.clone(),
+        sess.cfg_version,
+    );
+
     let stable_crate_id = base_n::encode(stable_crate_id.as_u64() as u128, INT_ENCODE_BASE);
 
     let crate_name = format!("{crate_name}-{stable_crate_id}");

compiler/rustc_incremental/src/persist/load.rs

@@ -8,8 +8,8 @@ use rustc_middle::query::on_disk_cache::OnDiskCache;
 use rustc_serialize::opaque::MemDecoder;
 use rustc_serialize::Decodable;
 use rustc_session::config::IncrementalStateAssertion;
-use rustc_session::{Session, StableCrateId};
-use rustc_span::{ErrorGuaranteed, Symbol};
+use rustc_session::Session;
+use rustc_span::ErrorGuaranteed;
 use std::path::{Path, PathBuf};
 
 use super::data::*;
@@ -190,13 +190,9 @@ pub fn load_query_result_cache(sess: &Session) -> Option<OnDiskCache<'_>> {
 
 /// Setups the dependency graph by loading an existing graph from disk and set up streaming of a
 /// new graph to an incremental session directory.
-pub fn setup_dep_graph(
-    sess: &Session,
-    crate_name: Symbol,
-    stable_crate_id: StableCrateId,
-) -> Result<DepGraph, ErrorGuaranteed> {
+pub fn setup_dep_graph(sess: &Session) -> Result<DepGraph, ErrorGuaranteed> {
     // `load_dep_graph` can only be called after `prepare_session_directory`.
-    prepare_session_directory(sess, crate_name, stable_crate_id)?;
+    prepare_session_directory(sess)?;
 
     let res = sess.opts.build_dep_graph().then(|| load_dep_graph(sess));
 

compiler/rustc_interface/messages.ftl

@@ -48,6 +48,3 @@ interface_rustc_error_unexpected_annotation =
 
 interface_temps_dir_error =
     failed to find or create the directory specified by `--temps-dir`
-
-interface_unsupported_crate_type_for_target =
-    dropping unsupported crate type `{$crate_type}` for target `{$target_triple}`

compiler/rustc_interface/src/errors.rs

@@ -1,7 +1,5 @@
 use rustc_macros::Diagnostic;
-use rustc_session::config::CrateType;
 use rustc_span::{Span, Symbol};
-use rustc_target::spec::TargetTriple;
 
 use std::io;
 use std::path::Path;
@@ -90,13 +88,6 @@ pub struct FailedWritingFile<'a> {
 #[diag(interface_proc_macro_crate_panic_abort)]
 pub struct ProcMacroCratePanicAbort;
 
-#[derive(Diagnostic)]
-#[diag(interface_unsupported_crate_type_for_target)]
-pub struct UnsupportedCrateTypeForTarget<'a> {
-    pub crate_type: CrateType,
-    pub target_triple: &'a TargetTriple,
-}
-
 #[derive(Diagnostic)]
 #[diag(interface_multiple_output_types_adaption)]
 pub struct MultipleOutputTypesAdaption;

compiler/rustc_interface/src/queries.rs

@@ -18,7 +18,7 @@ use rustc_middle::ty::{GlobalCtxt, TyCtxt};
 use rustc_serialize::opaque::FileEncodeResult;
 use rustc_session::config::{self, CrateType, OutputFilenames, OutputType};
 use rustc_session::cstore::Untracked;
-use rustc_session::output::find_crate_name;
+use rustc_session::output::{collect_crate_types, find_crate_name};
 use rustc_session::Session;
 use rustc_span::symbol::sym;
 use std::any::Any;
@@ -128,15 +128,15 @@ impl<'tcx> Queries<'tcx> {
 
             // parse `#[crate_name]` even if `--crate-name` was passed, to make sure it matches.
             let crate_name = find_crate_name(sess, &pre_configured_attrs);
-            let crate_types = util::collect_crate_types(sess, &pre_configured_attrs);
+            let crate_types = collect_crate_types(sess, &pre_configured_attrs);
             let stable_crate_id = StableCrateId::new(
                 crate_name,
                 crate_types.contains(&CrateType::Executable),
                 sess.opts.cg.metadata.clone(),
                 sess.cfg_version,
             );
             let outputs = util::build_output_filenames(&pre_configured_attrs, sess);
-            let dep_graph = setup_dep_graph(sess, crate_name, stable_crate_id)?;
+            let dep_graph = setup_dep_graph(sess)?;
 
             let cstore = FreezeLock::new(Box::new(CStore::new(
                 self.compiler.codegen_backend.metadata_loader(),

compiler/rustc_interface/src/util.rs

@@ -7,14 +7,15 @@ use rustc_data_structures::sync;
 use rustc_metadata::{load_symbol_from_dylib, DylibError};
 use rustc_parse::validate_attr;
 use rustc_session as session;
-use rustc_session::config::{self, Cfg, CrateType, OutFileName, OutputFilenames, OutputTypes};
+use rustc_session::config::{Cfg, OutFileName, OutputFilenames, OutputTypes};
 use rustc_session::filesearch::sysroot_candidates;
 use rustc_session::lint::{self, BuiltinLintDiag, LintBuffer};
-use rustc_session::{filesearch, output, Session};
+use rustc_session::{filesearch, Session};
 use rustc_span::edit_distance::find_best_match_for_name;
 use rustc_span::edition::Edition;
-use rustc_span::symbol::{sym, Symbol};
+use rustc_span::symbol::sym;
 use rustc_target::spec::Target;
+use session::output::{categorize_crate_type, CRATE_TYPES};
 use session::EarlyDiagCtxt;
 use std::env::consts::{DLL_PREFIX, DLL_SUFFIX};
 use std::path::{Path, PathBuf};
@@ -399,67 +400,6 @@ pub(crate) fn check_attr_crate_type(
     }
 }
 
-const CRATE_TYPES: &[(Symbol, CrateType)] = &[
-    (sym::rlib, CrateType::Rlib),
-    (sym::dylib, CrateType::Dylib),
-    (sym::cdylib, CrateType::Cdylib),
-    (sym::lib, config::default_lib_output()),
-    (sym::staticlib, CrateType::Staticlib),
-    (sym::proc_dash_macro, CrateType::ProcMacro),
-    (sym::bin, CrateType::Executable),
-];
-
-fn categorize_crate_type(s: Symbol) -> Option<CrateType> {
-    Some(CRATE_TYPES.iter().find(|(key, _)| *key == s)?.1)
-}
-
-pub fn collect_crate_types(session: &Session, attrs: &[ast::Attribute]) -> Vec<CrateType> {
-    // If we're generating a test executable, then ignore all other output
-    // styles at all other locations
-    if session.opts.test {
-        return vec![CrateType::Executable];
-    }
-
-    // Only check command line flags if present. If no types are specified by
-    // command line, then reuse the empty `base` Vec to hold the types that
-    // will be found in crate attributes.
-    // JUSTIFICATION: before wrapper fn is available
-    #[allow(rustc::bad_opt_access)]
-    let mut base = session.opts.crate_types.clone();
-    if base.is_empty() {
-        let attr_types = attrs.iter().filter_map(|a| {
-            if a.has_name(sym::crate_type)
-                && let Some(s) = a.value_str()
-            {
-                categorize_crate_type(s)
-            } else {
-                None
-            }
-        });
-        base.extend(attr_types);
-        if base.is_empty() {
-            base.push(output::default_output_for_target(session));
-        } else {
-            base.sort();
-            base.dedup();
-        }
-    }
-
-    base.retain(|crate_type| {
-        if output::invalid_output_for_target(session, *crate_type) {
-            session.dcx().emit_warn(errors::UnsupportedCrateTypeForTarget {
-                crate_type: *crate_type,
-                target_triple: &session.opts.target_triple,
-            });
-            false
-        } else {
-            true
-        }
-    });
-
-    base
-}
-
 fn multiple_output_types_to_stdout(
     output_types: &OutputTypes,
     single_output_file_is_stdout: bool,

compiler/rustc_lint_defs/src/builtin.rs

@@ -557,6 +557,7 @@ declare_lint! {
     /// fn main() {
     ///     use foo::bar;
     ///     foo::bar();
+    ///     bar();
     /// }
     /// ```
     ///

compiler/rustc_middle/src/ty/sty.rs

@@ -2436,8 +2436,9 @@ impl<'tcx> Ty<'tcx> {
             },
 
             // "Bound" types appear in canonical queries when the
-            // closure type is not yet known
-            Bound(..) | Param(_) | Infer(_) => None,
+            // closure type is not yet known, and `Placeholder` and `Param`
+            // may be encountered in generic `AsyncFnKindHelper` goals.
+            Bound(..) | Placeholder(_) | Param(_) | Infer(_) => None,
 
             Error(_) => Some(ty::ClosureKind::Fn),
 

compiler/rustc_mir_transform/src/dataflow_const_prop.rs

@@ -393,7 +393,9 @@ impl<'a, 'tcx> ConstAnalysis<'a, 'tcx> {
                 }
             }
             Operand::Constant(box constant) => {
-                if let Ok(constant) = self.ecx.eval_mir_constant(&constant.const_, None, None) {
+                if let Ok(constant) =
+                    self.ecx.eval_mir_constant(&constant.const_, Some(constant.span), None)
+                {
                     self.assign_constant(state, place, constant, &[]);
                 }
             }

compiler/rustc_mir_transform/src/jump_threading.rs

@@ -416,7 +416,8 @@ impl<'tcx, 'a> TOFinder<'tcx, 'a> {
         match rhs {
             // If we expect `lhs ?= A`, we have an opportunity if we assume `constant == A`.
             Operand::Constant(constant) => {
-                let constant = self.ecx.eval_mir_constant(&constant.const_, None, None).ok()?;
+                let constant =
+                    self.ecx.eval_mir_constant(&constant.const_, Some(constant.span), None).ok()?;
                 self.process_constant(bb, lhs, constant, state);
             }
             // Transfer the conditions on the copied rhs.

compiler/rustc_monomorphize/src/collector.rs

@@ -825,14 +825,17 @@ impl<'a, 'tcx> MirVisitor<'tcx> for MirUsedCollector<'a, 'tcx> {
     fn visit_constant(&mut self, constant: &mir::ConstOperand<'tcx>, location: Location) {
         let const_ = self.monomorphize(constant.const_);
         let param_env = ty::ParamEnv::reveal_all();
-        let val = match const_.eval(self.tcx, param_env, None) {
+        let val = match const_.eval(self.tcx, param_env, Some(constant.span)) {
             Ok(v) => v,
-            Err(ErrorHandled::Reported(..)) => return,
             Err(ErrorHandled::TooGeneric(..)) => span_bug!(
                 self.body.source_info(location).span,
                 "collection encountered polymorphic constant: {:?}",
                 const_
             ),
+            Err(err @ ErrorHandled::Reported(..)) => {
+                err.emit_note(self.tcx);
+                return;
+            }
         };
         collect_const_value(self.tcx, val, self.output);
         MirVisitor::visit_ty(self, const_.ty(), TyContext::Location(location));

compiler/rustc_resolve/src/check_unused.rs

@@ -23,18 +23,19 @@
 //  - `check_unused` finally emits the diagnostics based on the data generated
 //    in the last step
 
-use crate::imports::ImportKind;
+use crate::imports::{Import, ImportKind};
 use crate::module_to_string;
 use crate::Resolver;
 
-use crate::NameBindingKind;
+use crate::{LexicalScopeBinding, NameBindingKind};
 use rustc_ast as ast;
 use rustc_ast::visit::{self, Visitor};
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap, FxIndexSet};
 use rustc_data_structures::unord::UnordSet;
 use rustc_errors::{pluralize, MultiSpan};
 use rustc_hir::def::{DefKind, Res};
-use rustc_session::lint::builtin::{MACRO_USE_EXTERN_CRATE, UNUSED_EXTERN_CRATES, UNUSED_IMPORTS};
+use rustc_session::lint::builtin::{MACRO_USE_EXTERN_CRATE, UNUSED_EXTERN_CRATES};
+use rustc_session::lint::builtin::{UNUSED_IMPORTS, UNUSED_QUALIFICATIONS};
 use rustc_session::lint::BuiltinLintDiag;
 use rustc_span::symbol::{kw, Ident};
 use rustc_span::{Span, DUMMY_SP};
@@ -514,8 +515,59 @@ impl Resolver<'_, '_> {
             }
         }
 
+        let mut redundant_imports = UnordSet::default();
         for import in check_redundant_imports {
-            self.check_for_redundant_imports(import);
+            if self.check_for_redundant_imports(import)
+                && let Some(id) = import.id()
+            {
+                redundant_imports.insert(id);
+            }
+        }
+
+        // The lint fixes for unused_import and unnecessary_qualification may conflict.
+        // Deleting both unused imports and unnecessary segments of an item may result
+        // in the item not being found.
+        for unn_qua in &self.potentially_unnecessary_qualifications {
+            if let LexicalScopeBinding::Item(name_binding) = unn_qua.binding
+                && let NameBindingKind::Import { import, .. } = name_binding.kind
+                && (is_unused_import(import, &unused_imports)
+                    || is_redundant_import(import, &redundant_imports))
+            {
+                continue;
+            }
+
+            self.lint_buffer.buffer_lint_with_diagnostic(
+                UNUSED_QUALIFICATIONS,
+                unn_qua.node_id,
+                unn_qua.path_span,
+                "unnecessary qualification",
+                BuiltinLintDiag::UnusedQualifications { removal_span: unn_qua.removal_span },
+            );
+        }
+
+        fn is_redundant_import(
+            import: Import<'_>,
+            redundant_imports: &UnordSet<ast::NodeId>,
+        ) -> bool {
+            if let Some(id) = import.id()
+                && redundant_imports.contains(&id)
+            {
+                return true;
+            }
+            false
+        }
+
+        fn is_unused_import(
+            import: Import<'_>,
+            unused_imports: &FxIndexMap<ast::NodeId, UnusedImport>,
+        ) -> bool {
+            if let Some(unused_import) = unused_imports.get(&import.root_id)
+                && let Some(id) = import.id()
+                && unused_import.unused.contains(&id)
+            {
+                return true;
+            }
+            false
         }
     }
 }

compiler/rustc_resolve/src/imports.rs

@@ -1306,7 +1306,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         None
     }
 
-    pub(crate) fn check_for_redundant_imports(&mut self, import: Import<'a>) {
+    pub(crate) fn check_for_redundant_imports(&mut self, import: Import<'a>) -> bool {
         // This function is only called for single imports.
         let ImportKind::Single {
             source, target, ref source_bindings, ref target_bindings, id, ..
@@ -1317,12 +1317,12 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
 
         // Skip if the import is of the form `use source as target` and source != target.
         if source != target {
-            return;
+            return false;
         }
 
         // Skip if the import was produced by a macro.
         if import.parent_scope.expansion != LocalExpnId::ROOT {
-            return;
+            return false;
         }
 
         // Skip if we are inside a named module (in contrast to an anonymous
@@ -1332,7 +1332,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         if import.used.get() == Some(Used::Other)
             || self.effective_visibilities.is_exported(self.local_def_id(id))
         {
-            return;
+            return false;
         }
 
         let mut is_redundant = true;
@@ -1375,7 +1375,10 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                 format!("the item `{source}` is imported redundantly"),
                 BuiltinLintDiag::RedundantImport(redundant_spans, source),
             );
+            return true;
         }
+
+        false
     }
 
     fn resolve_glob_import(&mut self, import: Import<'a>) {

compiler/rustc_resolve/src/late.rs

@@ -580,6 +580,15 @@ impl MaybeExported<'_> {
     }
 }
 
+/// Used for recording UnnecessaryQualification.
+#[derive(Debug)]
+pub(crate) struct UnnecessaryQualification<'a> {
+    pub binding: LexicalScopeBinding<'a>,
+    pub node_id: NodeId,
+    pub path_span: Span,
+    pub removal_span: Span,
+}
+
 #[derive(Default)]
 struct DiagMetadata<'ast> {
     /// The current trait's associated items' ident, used for diagnostic suggestions.
@@ -4654,20 +4663,16 @@ impl<'a: 'ast, 'b, 'ast, 'tcx> LateResolutionVisitor<'a, 'b, 'ast, 'tcx> {
             let ns = if i + 1 == path.len() { ns } else { TypeNS };
             let res = self.r.partial_res_map.get(&seg.id?)?.full_res()?;
             let binding = self.resolve_ident_in_lexical_scope(seg.ident, ns, None, None)?;
-
-            (res == binding.res()).then_some(seg)
+            (res == binding.res()).then_some((seg, binding))
         });
 
-        if let Some(unqualified) = unqualified {
-            self.r.lint_buffer.buffer_lint_with_diagnostic(
-                lint::builtin::UNUSED_QUALIFICATIONS,
-                finalize.node_id,
-                finalize.path_span,
-                "unnecessary qualification",
-                lint::BuiltinLintDiag::UnusedQualifications {
-                    removal_span: path[0].ident.span.until(unqualified.ident.span),
-                },
-            );
+        if let Some((seg, binding)) = unqualified {
+            self.r.potentially_unnecessary_qualifications.push(UnnecessaryQualification {
+                binding,
+                node_id: finalize.node_id,
+                path_span: finalize.path_span,
+                removal_span: path[0].ident.span.until(seg.ident.span),
+            });
         }
     }
 }

compiler/rustc_resolve/src/lib.rs

@@ -68,7 +68,7 @@ use std::fmt;
 
 use diagnostics::{ImportSuggestion, LabelSuggestion, Suggestion};
 use imports::{Import, ImportData, ImportKind, NameResolution};
-use late::{HasGenericParams, PathSource, PatternSource};
+use late::{HasGenericParams, PathSource, PatternSource, UnnecessaryQualification};
 use macros::{MacroRulesBinding, MacroRulesScope, MacroRulesScopeRef};
 
 use crate::effective_visibilities::EffectiveVisibilitiesVisitor;
@@ -372,7 +372,7 @@ impl<'a> From<&'a ast::PathSegment> for Segment {
 /// This refers to the thing referred by a name. The difference between `Res` and `Item` is that
 /// items are visible in their whole block, while `Res`es only from the place they are defined
 /// forward.
-#[derive(Debug)]
+#[derive(Debug, Copy, Clone)]
 enum LexicalScopeBinding<'a> {
     Item(NameBinding<'a>),
     Res(Res),
@@ -1105,6 +1105,8 @@ pub struct Resolver<'a, 'tcx> {
 
     potentially_unused_imports: Vec<Import<'a>>,
 
+    potentially_unnecessary_qualifications: Vec<UnnecessaryQualification<'a>>,
+
     /// Table for mapping struct IDs into struct constructor IDs,
     /// it's not used during normal resolution, only for better error reporting.
     /// Also includes of list of each fields visibility
@@ -1464,6 +1466,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             local_macro_def_scopes: FxHashMap::default(),
             name_already_seen: FxHashMap::default(),
             potentially_unused_imports: Vec::new(),
+            potentially_unnecessary_qualifications: Default::default(),
             struct_constructors: Default::default(),
             unused_macros: Default::default(),
             unused_macro_rules: Default::default(),

compiler/rustc_session/messages.ftl

@@ -111,4 +111,7 @@ session_unleashed_feature_help_unnamed = skipping check that does not even have
 
 session_unstable_virtual_function_elimination = `-Zvirtual-function-elimination` requires `-Clto`
 
+session_unsupported_crate_type_for_target =
+    dropping unsupported crate type `{$crate_type}` for target `{$target_triple}`
+
 session_unsupported_dwarf_version = requested DWARF version {$dwarf_version} is greater than 5

compiler/rustc_session/src/errors.rs

@@ -10,7 +10,7 @@ use rustc_macros::Diagnostic;
 use rustc_span::{Span, Symbol};
 use rustc_target::spec::{SplitDebuginfo, StackProtector, TargetTriple};
 
-use crate::parse::ParseSess;
+use crate::{config::CrateType, parse::ParseSess};
 
 pub struct FeatureGateError {
     pub span: MultiSpan,
@@ -345,6 +345,13 @@ pub(crate) struct BinaryFloatLiteralNotSupported {
     pub span: Span,
 }
 
+#[derive(Diagnostic)]
+#[diag(session_unsupported_crate_type_for_target)]
+pub struct UnsupportedCrateTypeForTarget<'a> {
+    pub crate_type: CrateType,
+    pub target_triple: &'a TargetTriple,
+}
+
 pub fn report_lit_error(
     psess: &ParseSess,
     err: LitError,

compiler/rustc_session/src/output.rs

@@ -1,7 +1,7 @@
 //! Related to out filenames of compilation (e.g. binaries).
-use crate::config::{CrateType, Input, OutFileName, OutputFilenames, OutputType};
+use crate::config::{self, CrateType, Input, OutFileName, OutputFilenames, OutputType};
 use crate::errors::{
-    CrateNameDoesNotMatch, CrateNameEmpty, CrateNameInvalid, FileIsNotWriteable,
+    self, CrateNameDoesNotMatch, CrateNameEmpty, CrateNameInvalid, FileIsNotWriteable,
     InvalidCharacterInCrateName, InvalidCrateNameHelp,
 };
 use crate::Session;
@@ -200,3 +200,64 @@ pub fn invalid_output_for_target(sess: &Session, crate_type: CrateType) -> bool
 
     false
 }
+
+pub const CRATE_TYPES: &[(Symbol, CrateType)] = &[
+    (sym::rlib, CrateType::Rlib),
+    (sym::dylib, CrateType::Dylib),
+    (sym::cdylib, CrateType::Cdylib),
+    (sym::lib, config::default_lib_output()),
+    (sym::staticlib, CrateType::Staticlib),
+    (sym::proc_dash_macro, CrateType::ProcMacro),
+    (sym::bin, CrateType::Executable),
+];
+
+pub fn categorize_crate_type(s: Symbol) -> Option<CrateType> {
+    Some(CRATE_TYPES.iter().find(|(key, _)| *key == s)?.1)
+}
+
+pub fn collect_crate_types(session: &Session, attrs: &[ast::Attribute]) -> Vec<CrateType> {
+    // If we're generating a test executable, then ignore all other output
+    // styles at all other locations
+    if session.opts.test {
+        return vec![CrateType::Executable];
+    }
+
+    // Only check command line flags if present. If no types are specified by
+    // command line, then reuse the empty `base` Vec to hold the types that
+    // will be found in crate attributes.
+    // JUSTIFICATION: before wrapper fn is available
+    #[allow(rustc::bad_opt_access)]
+    let mut base = session.opts.crate_types.clone();
+    if base.is_empty() {
+        let attr_types = attrs.iter().filter_map(|a| {
+            if a.has_name(sym::crate_type)
+                && let Some(s) = a.value_str()
+            {
+                categorize_crate_type(s)
+            } else {
+                None
+            }
+        });
+        base.extend(attr_types);
+        if base.is_empty() {
+            base.push(default_output_for_target(session));
+        } else {
+            base.sort();
+            base.dedup();
+        }
+    }
+
+    base.retain(|crate_type| {
+        if invalid_output_for_target(session, *crate_type) {
+            session.dcx().emit_warn(errors::UnsupportedCrateTypeForTarget {
+                crate_type: *crate_type,
+                target_triple: &session.opts.target_triple,
+            });
+            false
+        } else {
+            true
+        }
+    });
+
+    base
+}

compiler/rustc_smir/src/rustc_smir/builder.rs

@@ -56,7 +56,7 @@ impl<'tcx> MutVisitor<'tcx> for BodyBuilder<'tcx> {
 
     fn visit_constant(&mut self, constant: &mut mir::ConstOperand<'tcx>, location: mir::Location) {
         let const_ = self.monomorphize(constant.const_);
-        let val = match const_.eval(self.tcx, ty::ParamEnv::reveal_all(), None) {
+        let val = match const_.eval(self.tcx, ty::ParamEnv::reveal_all(), Some(constant.span)) {
             Ok(v) => v,
             Err(mir::interpret::ErrorHandled::Reported(..)) => return,
             Err(mir::interpret::ErrorHandled::TooGeneric(..)) => {

library/core/src/iter/range.rs

@@ -22,7 +22,7 @@ unsafe_impl_trusted_step![AsciiChar char i8 i16 i32 i64 i128 isize u8 u16 u32 u6
 ///
 /// The *successor* operation moves towards values that compare greater.
 /// The *predecessor* operation moves towards values that compare lesser.
-#[unstable(feature = "step_trait", reason = "recently redesigned", issue = "42168")]
+#[unstable(feature = "step_trait", issue = "42168")]
 pub trait Step: Clone + PartialOrd + Sized {
     /// Returns the number of *successor* steps required to get from `start` to `end`.
     ///
@@ -52,15 +52,12 @@ pub trait Step: Clone + PartialOrd + Sized {
     /// For any `a`, `n`, and `m`:
     ///
     /// * `Step::forward_checked(a, n).and_then(|x| Step::forward_checked(x, m)) == Step::forward_checked(a, m).and_then(|x| Step::forward_checked(x, n))`
-    ///
-    /// For any `a`, `n`, and `m` where `n + m` does not overflow:
-    ///
-    /// * `Step::forward_checked(a, n).and_then(|x| Step::forward_checked(x, m)) == Step::forward_checked(a, n + m)`
+    /// * `Step::forward_checked(a, n).and_then(|x| Step::forward_checked(x, m)) == try { Step::forward_checked(a, n.checked_add(m)) }`
     ///
     /// For any `a` and `n`:
     ///
     /// * `Step::forward_checked(a, n) == (0..n).try_fold(a, |x, _| Step::forward_checked(&x, 1))`
-    ///   * Corollary: `Step::forward_checked(&a, 0) == Some(a)`
+    ///   * Corollary: `Step::forward_checked(a, 0) == Some(a)`
     fn forward_checked(start: Self, count: usize) -> Option<Self>;
 
     /// Returns the value that would be obtained by taking the *successor*
@@ -106,6 +103,7 @@ pub trait Step: Clone + PartialOrd + Sized {
     /// * if there exists `b` such that `b > a`, it is safe to call `Step::forward_unchecked(a, 1)`
     /// * if there exists `b`, `n` such that `steps_between(&a, &b) == Some(n)`,
     ///   it is safe to call `Step::forward_unchecked(a, m)` for any `m <= n`.
+    ///   * Corollary: `Step::forward_unchecked(a, 0)` is always safe.
     ///
     /// For any `a` and `n`, where no overflow occurs:
     ///
@@ -128,8 +126,8 @@ pub trait Step: Clone + PartialOrd + Sized {
     ///
     /// For any `a` and `n`:
     ///
-    /// * `Step::backward_checked(a, n) == (0..n).try_fold(a, |x, _| Step::backward_checked(&x, 1))`
-    ///   * Corollary: `Step::backward_checked(&a, 0) == Some(a)`
+    /// * `Step::backward_checked(a, n) == (0..n).try_fold(a, |x, _| Step::backward_checked(x, 1))`
+    ///   * Corollary: `Step::backward_checked(a, 0) == Some(a)`
     fn backward_checked(start: Self, count: usize) -> Option<Self>;
 
     /// Returns the value that would be obtained by taking the *predecessor*
@@ -175,6 +173,7 @@ pub trait Step: Clone + PartialOrd + Sized {
     /// * if there exists `b` such that `b < a`, it is safe to call `Step::backward_unchecked(a, 1)`
     /// * if there exists `b`, `n` such that `steps_between(&b, &a) == Some(n)`,
     ///   it is safe to call `Step::backward_unchecked(a, m)` for any `m <= n`.
+    ///   * Corollary: `Step::backward_unchecked(a, 0)` is always safe.
     ///
     /// For any `a` and `n`, where no overflow occurs:
     ///

library/std/src/os/windows/io/handle.rs

@@ -7,7 +7,7 @@ use crate::fmt;
 use crate::fs;
 use crate::io;
 use crate::marker::PhantomData;
-use crate::mem::forget;
+use crate::mem::{forget, ManuallyDrop};
 use crate::ptr;
 use crate::sys;
 use crate::sys::cvt;
@@ -91,7 +91,7 @@ pub struct OwnedHandle {
 #[repr(transparent)]
 #[stable(feature = "io_safety", since = "1.63.0")]
 #[derive(Debug)]
-pub struct HandleOrNull(OwnedHandle);
+pub struct HandleOrNull(RawHandle);
 
 /// FFI type for handles in return values or out parameters, where `INVALID_HANDLE_VALUE` is used
 /// as a sentry value to indicate errors, such as in the return value of `CreateFileW`. This uses
@@ -110,7 +110,7 @@ pub struct HandleOrNull(OwnedHandle);
 #[repr(transparent)]
 #[stable(feature = "io_safety", since = "1.63.0")]
 #[derive(Debug)]
-pub struct HandleOrInvalid(OwnedHandle);
+pub struct HandleOrInvalid(RawHandle);
 
 // The Windows [`HANDLE`] type may be transferred across and shared between
 // thread boundaries (despite containing a `*mut void`, which in general isn't
@@ -163,15 +163,24 @@ impl TryFrom<HandleOrNull> for OwnedHandle {
 
     #[inline]
     fn try_from(handle_or_null: HandleOrNull) -> Result<Self, NullHandleError> {
-        let owned_handle = handle_or_null.0;
-        if owned_handle.handle.is_null() {
-            // Don't call `CloseHandle`; it'd be harmless, except that it could
-            // overwrite the `GetLastError` error.
-            forget(owned_handle);
-
-            Err(NullHandleError(()))
+        let handle_or_null = ManuallyDrop::new(handle_or_null);
+        if handle_or_null.is_valid() {
+            // SAFETY: The handle is not null.
+            Ok(unsafe { OwnedHandle::from_raw_handle(handle_or_null.0) })
         } else {
-            Ok(owned_handle)
+            Err(NullHandleError(()))
+        }
+    }
+}
+
+#[stable(feature = "io_safety", since = "1.63.0")]
+impl Drop for HandleOrNull {
+    #[inline]
+    fn drop(&mut self) {
+        if self.is_valid() {
+            unsafe {
+                let _ = sys::c::CloseHandle(self.0);
+            }
         }
     }
 }
@@ -232,15 +241,24 @@ impl TryFrom<HandleOrInvalid> for OwnedHandle {
 
     #[inline]
     fn try_from(handle_or_invalid: HandleOrInvalid) -> Result<Self, InvalidHandleError> {
-        let owned_handle = handle_or_invalid.0;
-        if owned_handle.handle == sys::c::INVALID_HANDLE_VALUE {
-            // Don't call `CloseHandle`; it'd be harmless, except that it could
-            // overwrite the `GetLastError` error.
-            forget(owned_handle);
-
-            Err(InvalidHandleError(()))
+        let handle_or_invalid = ManuallyDrop::new(handle_or_invalid);
+        if handle_or_invalid.is_valid() {
+            // SAFETY: The handle is not invalid.
+            Ok(unsafe { OwnedHandle::from_raw_handle(handle_or_invalid.0) })
         } else {
-            Ok(owned_handle)
+            Err(InvalidHandleError(()))
+        }
+    }
+}
+
+#[stable(feature = "io_safety", since = "1.63.0")]
+impl Drop for HandleOrInvalid {
+    #[inline]
+    fn drop(&mut self) {
+        if self.is_valid() {
+            unsafe {
+                let _ = sys::c::CloseHandle(self.0);
+            }
         }
     }
 }
@@ -333,7 +351,11 @@ impl HandleOrNull {
     #[stable(feature = "io_safety", since = "1.63.0")]
     #[inline]
     pub unsafe fn from_raw_handle(handle: RawHandle) -> Self {
-        Self(OwnedHandle::from_raw_handle(handle))
+        Self(handle)
+    }
+
+    fn is_valid(&self) -> bool {
+        !self.0.is_null()
     }
 }
 
@@ -356,7 +378,11 @@ impl HandleOrInvalid {
     #[stable(feature = "io_safety", since = "1.63.0")]
     #[inline]
     pub unsafe fn from_raw_handle(handle: RawHandle) -> Self {
-        Self(OwnedHandle::from_raw_handle(handle))
+        Self(handle)
+    }
+
+    fn is_valid(&self) -> bool {
+        self.0 != sys::c::INVALID_HANDLE_VALUE
     }
 }
 

tests/ui/consts/assoc_const_generic_impl.stderr

@@ -4,6 +4,12 @@ error[E0080]: evaluation of `<u32 as ZeroSized>::I_AM_ZERO_SIZED` failed
 LL |     const I_AM_ZERO_SIZED: ()  = [()][std::mem::size_of::<Self>()];
    |                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ index out of bounds: the length is 1 but the index is 4
 
+note: erroneous constant encountered
+  --> $DIR/assoc_const_generic_impl.rs:11:9
+   |
+LL |         Self::I_AM_ZERO_SIZED;
+   |         ^^^^^^^^^^^^^^^^^^^^^
+
 note: the above error was encountered while instantiating `fn <u32 as ZeroSized>::requires_zero_size`
   --> $DIR/assoc_const_generic_impl.rs:18:5
    |

tests/ui/consts/const-eval/index-out-of-bounds-never-type.stderr

@@ -4,6 +4,12 @@ error[E0080]: evaluation of `PrintName::<()>::VOID` failed
 LL |     const VOID: ! = { let x = 0 * std::mem::size_of::<T>(); [][x] };
    |                                                             ^^^^^ index out of bounds: the length is 0 but the index is 0
 
+note: erroneous constant encountered
+  --> $DIR/index-out-of-bounds-never-type.rs:16:13
+   |
+LL |     let _ = PrintName::<T>::VOID;
+   |             ^^^^^^^^^^^^^^^^^^^^
+
 note: the above error was encountered while instantiating `fn f::<()>`
   --> $DIR/index-out-of-bounds-never-type.rs:20:5
    |

tests/ui/consts/const-eval/issue-50814-2.mir-opt.stderr

@@ -10,6 +10,52 @@ note: erroneous constant encountered
 LL |     &<A<T> as Foo<T>>::BAR
    |      ^^^^^^^^^^^^^^^^^^^^^
 
+note: erroneous constant encountered
+  --> $DIR/issue-50814-2.rs:20:5
+   |
+LL |     &<A<T> as Foo<T>>::BAR
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+
+note: erroneous constant encountered
+  --> $DIR/issue-50814-2.rs:20:5
+   |
+LL |     &<A<T> as Foo<T>>::BAR
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+note: erroneous constant encountered
+  --> $DIR/issue-50814-2.rs:20:5
+   |
+LL |     &<A<T> as Foo<T>>::BAR
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+note: erroneous constant encountered
+  --> $DIR/issue-50814-2.rs:20:5
+   |
+LL |     &<A<T> as Foo<T>>::BAR
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+note: erroneous constant encountered
+  --> $DIR/issue-50814-2.rs:20:6
+   |
+LL |     &<A<T> as Foo<T>>::BAR
+   |      ^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+note: erroneous constant encountered
+  --> $DIR/issue-50814-2.rs:20:6
+   |
+LL |     &<A<T> as Foo<T>>::BAR
+   |      ^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
 error: aborting due to 1 previous error
 
 For more information about this error, try `rustc --explain E0080`.

tests/ui/consts/const-eval/issue-50814-2.normal.stderr

@@ -10,6 +10,20 @@ note: erroneous constant encountered
 LL |     &<A<T> as Foo<T>>::BAR
    |      ^^^^^^^^^^^^^^^^^^^^^
 
+note: erroneous constant encountered
+  --> $DIR/issue-50814-2.rs:20:5
+   |
+LL |     &<A<T> as Foo<T>>::BAR
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+
+note: erroneous constant encountered
+  --> $DIR/issue-50814-2.rs:20:6
+   |
+LL |     &<A<T> as Foo<T>>::BAR
+   |      ^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
 note: the above error was encountered while instantiating `fn foo::<()>`
   --> $DIR/issue-50814-2.rs:32:22
    |

tests/ui/consts/const-eval/issue-50814.stderr

@@ -26,6 +26,20 @@ LL |     &Sum::<U8, U8>::MAX
    |
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
+note: erroneous constant encountered
+  --> $DIR/issue-50814.rs:21:5
+   |
+LL |     &Sum::<U8, U8>::MAX
+   |     ^^^^^^^^^^^^^^^^^^^
+
+note: erroneous constant encountered
+  --> $DIR/issue-50814.rs:21:6
+   |
+LL |     &Sum::<U8, U8>::MAX
+   |      ^^^^^^^^^^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
 note: the above error was encountered while instantiating `fn foo::<i32>`
   --> $DIR/issue-50814.rs:26:5
    |

tests/ui/consts/const-eval/issue-85155.stderr

@@ -4,6 +4,14 @@ error[E0080]: evaluation of `post_monomorphization_error::ValidateConstImm::<2,
 LL |         let _ = 1 / ((IMM >= MIN && IMM <= MAX) as usize);
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ attempt to divide `1_usize` by zero
 
+note: erroneous constant encountered
+  --> $DIR/auxiliary/post_monomorphization_error.rs:19:5
+   |
+LL |     static_assert_imm1!(IMM1);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: this note originates in the macro `static_assert_imm1` (in Nightly builds, run with -Z macro-backtrace for more info)
+
 note: the above error was encountered while instantiating `fn post_monomorphization_error::stdarch_intrinsic::<2>`
   --> $DIR/issue-85155.rs:19:5
    |

tests/ui/consts/const-eval/unused-broken-const-late.stderr

@@ -6,6 +6,12 @@ LL |     const VOID: () = panic!();
    |
    = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)
 
+note: erroneous constant encountered
+  --> $DIR/unused-broken-const-late.rs:15:17
+   |
+LL |         let _ = PrintName::<T>::VOID;
+   |                 ^^^^^^^^^^^^^^^^^^^^
+
 error: aborting due to 1 previous error
 
 For more information about this error, try `rustc --explain E0080`.

tests/ui/inline-const/const-expr-generic-err.stderr

@@ -6,6 +6,12 @@ LL |     const { assert!(std::mem::size_of::<T>() == 0); }
    |
    = note: this error originates in the macro `assert` (in Nightly builds, run with -Z macro-backtrace for more info)
 
+note: erroneous constant encountered
+  --> $DIR/const-expr-generic-err.rs:5:5
+   |
+LL |     const { assert!(std::mem::size_of::<T>() == 0); }
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
 note: the above error was encountered while instantiating `fn foo::<i32>`
   --> $DIR/const-expr-generic-err.rs:13:5
    |
@@ -18,6 +24,20 @@ error[E0080]: evaluation of `bar::<0>::{constant#0}` failed
 LL |     const { N - 1 }
    |             ^^^^^ attempt to compute `0_usize - 1_usize`, which would overflow
 
+note: erroneous constant encountered
+  --> $DIR/const-expr-generic-err.rs:9:5
+   |
+LL |     const { N - 1 }
+   |     ^^^^^^^^^^^^^^^
+
+note: erroneous constant encountered
+  --> $DIR/const-expr-generic-err.rs:9:5
+   |
+LL |     const { N - 1 }
+   |     ^^^^^^^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
 note: the above error was encountered while instantiating `fn bar::<0>`
   --> $DIR/const-expr-generic-err.rs:14:5
    |

tests/ui/inline-const/required-const.stderr

@@ -6,6 +6,12 @@ LL |         const { panic!() }
    |
    = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)
 
+note: erroneous constant encountered
+  --> $DIR/required-const.rs:7:9
+   |
+LL |         const { panic!() }
+   |         ^^^^^^^^^^^^^^^^^^
+
 error: aborting due to 1 previous error
 
 For more information about this error, try `rustc --explain E0080`.

tests/ui/lint/lint-qualification.fixed

@@ -1,5 +1,6 @@
 //@ run-rustfix
 #![deny(unused_qualifications)]
+#![deny(unused_imports)]
 #![allow(deprecated, dead_code)]
 
 mod foo {
@@ -21,8 +22,10 @@ fn main() {
     //~^ ERROR: unnecessary qualification
     //~| ERROR: unnecessary qualification
 
-    use std::fmt;
-    let _: fmt::Result = Ok(()); //~ ERROR: unnecessary qualification
+
+    //~^ ERROR: unused import: `std::fmt`
+    let _: std::fmt::Result = Ok(());
+    // don't report unnecessary qualification because fix(#122373) for issue #121331
 
     let _ = <bool as Default>::default(); // issue #121999
     //~^ ERROR: unnecessary qualification

tests/ui/lint/lint-qualification.rs

@@ -1,5 +1,6 @@
 //@ run-rustfix
 #![deny(unused_qualifications)]
+#![deny(unused_imports)]
 #![allow(deprecated, dead_code)]
 
 mod foo {
@@ -22,7 +23,9 @@ fn main() {
     //~| ERROR: unnecessary qualification
 
     use std::fmt;
-    let _: std::fmt::Result = Ok(()); //~ ERROR: unnecessary qualification
+    //~^ ERROR: unused import: `std::fmt`
+    let _: std::fmt::Result = Ok(());
+    // don't report unnecessary qualification because fix(#122373) for issue #121331
 
     let _ = <bool as ::std::default::Default>::default(); // issue #121999
     //~^ ERROR: unnecessary qualification

tests/ui/lint/lint-qualification.stderr

@@ -1,5 +1,5 @@
 error: unnecessary qualification
-  --> $DIR/lint-qualification.rs:11:5
+  --> $DIR/lint-qualification.rs:12:5
    |
 LL |     foo::bar();
    |     ^^^^^^^^
@@ -16,7 +16,7 @@ LL +     bar();
    |
 
 error: unnecessary qualification
-  --> $DIR/lint-qualification.rs:12:5
+  --> $DIR/lint-qualification.rs:13:5
    |
 LL |     crate::foo::bar();
    |     ^^^^^^^^^^^^^^^
@@ -28,7 +28,7 @@ LL +     bar();
    |
 
 error: unnecessary qualification
-  --> $DIR/lint-qualification.rs:17:13
+  --> $DIR/lint-qualification.rs:18:13
    |
 LL |     let _ = std::string::String::new();
    |             ^^^^^^^^^^^^^^^^^^^^^^^^
@@ -40,7 +40,7 @@ LL +     let _ = String::new();
    |
 
 error: unnecessary qualification
-  --> $DIR/lint-qualification.rs:18:13
+  --> $DIR/lint-qualification.rs:19:13
    |
 LL |     let _ = ::std::env::current_dir();
    |             ^^^^^^^^^^^^^^^^^^^^^^^
@@ -52,7 +52,7 @@ LL +     let _ = std::env::current_dir();
    |
 
 error: unnecessary qualification
-  --> $DIR/lint-qualification.rs:20:12
+  --> $DIR/lint-qualification.rs:21:12
    |
 LL |     let _: std::vec::Vec<String> = std::vec::Vec::<String>::new();
    |            ^^^^^^^^^^^^^^^^^^^^^
@@ -64,7 +64,7 @@ LL +     let _: Vec<String> = std::vec::Vec::<String>::new();
    |
 
 error: unnecessary qualification
-  --> $DIR/lint-qualification.rs:20:36
+  --> $DIR/lint-qualification.rs:21:36
    |
 LL |     let _: std::vec::Vec<String> = std::vec::Vec::<String>::new();
    |                                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -75,20 +75,20 @@ LL -     let _: std::vec::Vec<String> = std::vec::Vec::<String>::new();
 LL +     let _: std::vec::Vec<String> = Vec::<String>::new();
    |
 
-error: unnecessary qualification
-  --> $DIR/lint-qualification.rs:25:12
-   |
-LL |     let _: std::fmt::Result = Ok(());
-   |            ^^^^^^^^^^^^^^^^
+error: unused import: `std::fmt`
+  --> $DIR/lint-qualification.rs:25:9
    |
-help: remove the unnecessary path segments
+LL |     use std::fmt;
+   |         ^^^^^^^^
    |
-LL -     let _: std::fmt::Result = Ok(());
-LL +     let _: fmt::Result = Ok(());
+note: the lint level is defined here
+  --> $DIR/lint-qualification.rs:3:9
    |
+LL | #![deny(unused_imports)]
+   |         ^^^^^^^^^^^^^^
 
 error: unnecessary qualification
-  --> $DIR/lint-qualification.rs:27:13
+  --> $DIR/lint-qualification.rs:30:13
    |
 LL |     let _ = <bool as ::std::default::Default>::default(); // issue #121999
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

tests/ui/lint/unnecessary-qualification/lint-unnecessary-qualification-issue-121331.fixed

@@ -0,0 +1,50 @@
+//@ run-rustfix
+//@ edition:2021
+#![deny(unused_qualifications)]
+#![deny(unused_imports)]
+#![feature(coroutines, coroutine_trait)]
+
+use std::ops::{
+    Coroutine,
+    CoroutineState::{self},
+    //~^ ERROR unused import: `*`
+};
+use std::pin::Pin;
+
+#[allow(dead_code)]
+fn finish<T>(mut amt: usize, mut t: T) -> T::Return
+    where T: Coroutine<(), Yield = ()> + Unpin,
+{
+    loop {
+        match Pin::new(&mut t).resume(()) {
+            CoroutineState::Yielded(()) => amt = amt.checked_sub(1).unwrap(),
+            CoroutineState::Complete(ret) => {
+                assert_eq!(amt, 0);
+                return ret
+            }
+        }
+    }
+}
+
+
+mod foo {
+    pub fn bar() {}
+}
+
+pub fn main() {
+
+    use foo::bar;
+    bar();
+    //~^ ERROR unnecessary qualification
+    bar();
+
+    // The item `use std::string::String` is imported redundantly.
+    // Suppress `unused_imports` reporting, otherwise the fixed file will report an error
+    #[allow(unused_imports)]
+    use std::string::String;
+    let s = String::new();
+    let y = std::string::String::new();
+    // unnecessary qualification
+    println!("{} {}", s, y);
+
+}

tests/ui/lint/unnecessary-qualification/lint-unnecessary-qualification-issue-121331.rs

@@ -0,0 +1,50 @@
+//@ run-rustfix
+//@ edition:2021
+#![deny(unused_qualifications)]
+#![deny(unused_imports)]
+#![feature(coroutines, coroutine_trait)]
+
+use std::ops::{
+    Coroutine,
+    CoroutineState::{self, *},
+    //~^ ERROR unused import: `*`
+};
+use std::pin::Pin;
+
+#[allow(dead_code)]
+fn finish<T>(mut amt: usize, mut t: T) -> T::Return
+    where T: Coroutine<(), Yield = ()> + Unpin,
+{
+    loop {
+        match Pin::new(&mut t).resume(()) {
+            CoroutineState::Yielded(()) => amt = amt.checked_sub(1).unwrap(),
+            CoroutineState::Complete(ret) => {
+                assert_eq!(amt, 0);
+                return ret
+            }
+        }
+    }
+}
+
+
+mod foo {
+    pub fn bar() {}
+}
+
+pub fn main() {
+
+    use foo::bar;
+    foo::bar();
+    //~^ ERROR unnecessary qualification
+    bar();
+
+    // The item `use std::string::String` is imported redundantly.
+    // Suppress `unused_imports` reporting, otherwise the fixed file will report an error
+    #[allow(unused_imports)]
+    use std::string::String;
+    let s = String::new();
+    let y = std::string::String::new();
+    // unnecessary qualification
+    println!("{} {}", s, y);
+
+}

tests/ui/lint/unnecessary-qualification/lint-unnecessary-qualification-issue-121331.stderr

@@ -0,0 +1,31 @@
+error: unused import: `*`
+  --> $DIR/lint-unnecessary-qualification-issue-121331.rs:9:28
+   |
+LL |     CoroutineState::{self, *},
+   |                            ^
+   |
+note: the lint level is defined here
+  --> $DIR/lint-unnecessary-qualification-issue-121331.rs:4:9
+   |
+LL | #![deny(unused_imports)]
+   |         ^^^^^^^^^^^^^^
+
+error: unnecessary qualification
+  --> $DIR/lint-unnecessary-qualification-issue-121331.rs:37:5
+   |
+LL |     foo::bar();
+   |     ^^^^^^^^
+   |
+note: the lint level is defined here
+  --> $DIR/lint-unnecessary-qualification-issue-121331.rs:3:9
+   |
+LL | #![deny(unused_qualifications)]
+   |         ^^^^^^^^^^^^^^^^^^^^^
+help: remove the unnecessary path segments
+   |
+LL -     foo::bar();
+LL +     bar();
+   |
+
+error: aborting due to 2 previous errors
+

tests/ui/resolve/issue-113808-invalid-unused-qualifications-suggestion.fixed

@@ -18,6 +18,16 @@ impl Index<str> for A {
     }
 }
 
+// This is used to make `use std::ops::Index;` not unused_import.
+// details in fix(#122373) for issue #121331
+pub struct C;
+impl Index<str> for C {
+    type Output = ();
+    fn index(&self, _: str) -> &Self::Output {
+        &()
+    }
+}
+
 mod inner {
     pub trait Trait<T> {}
 }
@@ -29,4 +39,5 @@ use inner::Trait;
 impl Trait<u8> for () {}
 //~^ ERROR unnecessary qualification
 
+impl Trait<A> for A {}
 fn main() {}

tests/ui/resolve/issue-113808-invalid-unused-qualifications-suggestion.rs

@@ -18,6 +18,16 @@ impl ops::Index<str> for A {
     }
 }
 
+// This is used to make `use std::ops::Index;` not unused_import.
+// details in fix(#122373) for issue #121331
+pub struct C;
+impl Index<str> for C {
+    type Output = ();
+    fn index(&self, _: str) -> &Self::Output {
+        &()
+    }
+}
+
 mod inner {
     pub trait Trait<T> {}
 }
@@ -29,4 +39,5 @@ use inner::Trait;
 impl inner::Trait<u8> for () {}
 //~^ ERROR unnecessary qualification
 
+impl Trait<A> for A {}
 fn main() {}

tests/ui/resolve/issue-113808-invalid-unused-qualifications-suggestion.stderr

@@ -16,7 +16,7 @@ LL + impl Index<str> for A {
    |
 
 error: unnecessary qualification
-  --> $DIR/issue-113808-invalid-unused-qualifications-suggestion.rs:29:6
+  --> $DIR/issue-113808-invalid-unused-qualifications-suggestion.rs:39:6
    |
 LL | impl inner::Trait<u8> for () {}
    |      ^^^^^^^^^^^^^^^^

tests/ui/resolve/unused-qualifications-suggestion.fixed

@@ -16,8 +16,10 @@ fn main() {
     use foo::bar;
     bar();
     //~^ ERROR unnecessary qualification
+    bar();
 
     use baz::qux::quux;
     quux();
     //~^ ERROR unnecessary qualification
+    quux();
 }

tests/ui/resolve/unused-qualifications-suggestion.rs

@@ -16,8 +16,10 @@ fn main() {
     use foo::bar;
     foo::bar();
     //~^ ERROR unnecessary qualification
+    bar();
 
     use baz::qux::quux;
     baz::qux::quux();
     //~^ ERROR unnecessary qualification
+    quux();
 }

tests/ui/resolve/unused-qualifications-suggestion.stderr

@@ -16,7 +16,7 @@ LL +     bar();
    |
 
 error: unnecessary qualification
-  --> $DIR/unused-qualifications-suggestion.rs:21:5
+  --> $DIR/unused-qualifications-suggestion.rs:22:5
    |
 LL |     baz::qux::quux();
    |     ^^^^^^^^^^^^^^