Auto merge of #99047 - matthiaskrgr:rollup-01vn70s, r=matthiaskrgr

Rollup of 6 pull requests

Successful merges:

 - #95635 (sess: stabilize `--terminal-width` as `--diagnostic-width`)
 - #98718 (Stabilize `into_future`)
 - #98795 (A few cleanups)
 - #98798 (Fix caching bug in `download-rustc = true`)
 - #99019 (Add doc comments in `rustc_middle::mir`)
 - #99026 (Add test for and fix rust-lang/rust-clippy#9131)

Failed merges:

 - #98957 ( don't allow ZST in ScalarInt )

r? `@ghost`
`@rustbot` modify labels: rollup

compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -495,8 +495,7 @@ fn init_free_and_bound_regions(&mut self) {
                     }
                 }
 
-                NllRegionVariableOrigin::RootEmptyRegion
-                | NllRegionVariableOrigin::Existential { .. } => {
+                NllRegionVariableOrigin::Existential { .. } => {
                     // For existential, regions, nothing to do.
                 }
             }
@@ -1410,8 +1409,7 @@ fn check_universal_regions(
                     self.check_bound_universal_region(fr, placeholder, errors_buffer);
                 }
 
-                NllRegionVariableOrigin::RootEmptyRegion
-                | NllRegionVariableOrigin::Existential { .. } => {
+                NllRegionVariableOrigin::Existential { .. } => {
                     // nothing to check here
                 }
             }
@@ -1513,8 +1511,7 @@ fn check_polonius_subset_errors(
                     self.check_bound_universal_region(fr, placeholder, errors_buffer);
                 }
 
-                NllRegionVariableOrigin::RootEmptyRegion
-                | NllRegionVariableOrigin::Existential { .. } => {
+                NllRegionVariableOrigin::Existential { .. } => {
                     // nothing to check here
                 }
             }
@@ -1788,9 +1785,9 @@ pub(crate) fn cannot_name_placeholder(&self, r1: RegionVid, r2: RegionVid) -> bo
                 universe1.cannot_name(placeholder.universe)
             }
 
-            NllRegionVariableOrigin::RootEmptyRegion
-            | NllRegionVariableOrigin::FreeRegion
-            | NllRegionVariableOrigin::Existential { .. } => false,
+            NllRegionVariableOrigin::FreeRegion | NllRegionVariableOrigin::Existential { .. } => {
+                false
+            }
         }
     }
 
@@ -2152,8 +2149,7 @@ pub(crate) fn best_blame_constraint(
         let blame_source = match from_region_origin {
             NllRegionVariableOrigin::FreeRegion
             | NllRegionVariableOrigin::Existential { from_forall: false } => true,
-            NllRegionVariableOrigin::RootEmptyRegion
-            | NllRegionVariableOrigin::Placeholder(_)
+            NllRegionVariableOrigin::Placeholder(_)
             | NllRegionVariableOrigin::Existential { from_forall: true } => false,
         };
 

compiler/rustc_borrowck/src/universal_regions.rs

@@ -503,7 +503,7 @@ fn build(self) -> UniversalRegions<'tcx> {
 
         let root_empty = self
             .infcx
-            .next_nll_region_var(NllRegionVariableOrigin::RootEmptyRegion)
+            .next_nll_region_var(NllRegionVariableOrigin::Existential { from_forall: true })
             .to_region_vid();
 
         UniversalRegions {

compiler/rustc_errors/src/emitter.rs

@@ -63,7 +63,7 @@ pub fn new_emitter(
         bundle: Option<Lrc<FluentBundle>>,
         fallback_bundle: LazyFallbackBundle,
         teach: bool,
-        terminal_width: Option<usize>,
+        diagnostic_width: Option<usize>,
         macro_backtrace: bool,
     ) -> EmitterWriter {
         let (short, color_config) = self.unzip();
@@ -76,7 +76,7 @@ pub fn new_emitter(
             short,
             teach,
             color,
-            terminal_width,
+            diagnostic_width,
             macro_backtrace,
         )
     }
@@ -710,7 +710,7 @@ pub struct EmitterWriter {
     short_message: bool,
     teach: bool,
     ui_testing: bool,
-    terminal_width: Option<usize>,
+    diagnostic_width: Option<usize>,
 
     macro_backtrace: bool,
 }
@@ -730,7 +730,7 @@ pub fn stderr(
         fallback_bundle: LazyFallbackBundle,
         short_message: bool,
         teach: bool,
-        terminal_width: Option<usize>,
+        diagnostic_width: Option<usize>,
         macro_backtrace: bool,
     ) -> EmitterWriter {
         let dst = Destination::from_stderr(color_config);
@@ -742,7 +742,7 @@ pub fn stderr(
             short_message,
             teach,
             ui_testing: false,
-            terminal_width,
+            diagnostic_width,
             macro_backtrace,
         }
     }
@@ -755,7 +755,7 @@ pub fn new(
         short_message: bool,
         teach: bool,
         colored: bool,
-        terminal_width: Option<usize>,
+        diagnostic_width: Option<usize>,
         macro_backtrace: bool,
     ) -> EmitterWriter {
         EmitterWriter {
@@ -766,7 +766,7 @@ pub fn new(
             short_message,
             teach,
             ui_testing: false,
-            terminal_width,
+            diagnostic_width,
             macro_backtrace,
         }
     }
@@ -1615,7 +1615,7 @@ fn emit_message_default(
                     width_offset + annotated_file.multiline_depth + 1
                 };
 
-                let column_width = if let Some(width) = self.terminal_width {
+                let column_width = if let Some(width) = self.diagnostic_width {
                     width.saturating_sub(code_offset)
                 } else if self.ui_testing {
                     DEFAULT_COLUMN_WIDTH

compiler/rustc_errors/src/json.rs

@@ -42,7 +42,7 @@ pub struct JsonEmitter {
     pretty: bool,
     ui_testing: bool,
     json_rendered: HumanReadableErrorType,
-    terminal_width: Option<usize>,
+    diagnostic_width: Option<usize>,
     macro_backtrace: bool,
 }
 
@@ -54,7 +54,7 @@ pub fn stderr(
         fallback_bundle: LazyFallbackBundle,
         pretty: bool,
         json_rendered: HumanReadableErrorType,
-        terminal_width: Option<usize>,
+        diagnostic_width: Option<usize>,
         macro_backtrace: bool,
     ) -> JsonEmitter {
         JsonEmitter {
@@ -66,7 +66,7 @@ pub fn stderr(
             pretty,
             ui_testing: false,
             json_rendered,
-            terminal_width,
+            diagnostic_width,
             macro_backtrace,
         }
     }
@@ -76,7 +76,7 @@ pub fn basic(
         json_rendered: HumanReadableErrorType,
         fluent_bundle: Option<Lrc<FluentBundle>>,
         fallback_bundle: LazyFallbackBundle,
-        terminal_width: Option<usize>,
+        diagnostic_width: Option<usize>,
         macro_backtrace: bool,
     ) -> JsonEmitter {
         let file_path_mapping = FilePathMapping::empty();
@@ -87,7 +87,7 @@ pub fn basic(
             fallback_bundle,
             pretty,
             json_rendered,
-            terminal_width,
+            diagnostic_width,
             macro_backtrace,
         )
     }
@@ -100,7 +100,7 @@ pub fn new(
         fallback_bundle: LazyFallbackBundle,
         pretty: bool,
         json_rendered: HumanReadableErrorType,
-        terminal_width: Option<usize>,
+        diagnostic_width: Option<usize>,
         macro_backtrace: bool,
     ) -> JsonEmitter {
         JsonEmitter {
@@ -112,7 +112,7 @@ pub fn new(
             pretty,
             ui_testing: false,
             json_rendered,
-            terminal_width,
+            diagnostic_width,
             macro_backtrace,
         }
     }
@@ -345,7 +345,7 @@ fn flush(&mut self) -> io::Result<()> {
                 je.fluent_bundle.clone(),
                 je.fallback_bundle.clone(),
                 false,
-                je.terminal_width,
+                je.diagnostic_width,
                 je.macro_backtrace,
             )
             .ui_testing(je.ui_testing)

compiler/rustc_infer/src/infer/free_regions.rs

@@ -4,7 +4,7 @@
 //! and use that to decide when one free region outlives another, and so forth.
 
 use rustc_data_structures::transitive_relation::TransitiveRelation;
-use rustc_middle::ty::{self, Lift, Region, TyCtxt};
+use rustc_middle::ty::{Lift, Region, TyCtxt};
 
 /// Combines a `FreeRegionMap` and a `TyCtxt`.
 ///
@@ -49,7 +49,7 @@ pub fn is_empty(&self) -> bool {
     // (with the exception that `'static: 'x` is not notable)
     pub fn relate_regions(&mut self, sub: Region<'tcx>, sup: Region<'tcx>) {
         debug!("relate_regions(sub={:?}, sup={:?})", sub, sup);
-        if self.is_free_or_static(sub) && self.is_free(sup) {
+        if sub.is_free_or_static() && sup.is_free() {
             self.relation.add(sub, sup)
         }
     }
@@ -68,7 +68,7 @@ pub fn sub_free_regions(
         r_a: Region<'tcx>,
         r_b: Region<'tcx>,
     ) -> bool {
-        assert!(self.is_free_or_static(r_a) && self.is_free_or_static(r_b));
+        assert!(r_a.is_free_or_static() && r_b.is_free_or_static());
         let re_static = tcx.lifetimes.re_static;
         if self.check_relation(re_static, r_b) {
             // `'a <= 'static` is always true, and not stored in the
@@ -85,20 +85,6 @@ fn check_relation(&self, r_a: Region<'tcx>, r_b: Region<'tcx>) -> bool {
         r_a == r_b || self.relation.contains(r_a, r_b)
     }
 
-    /// True for free regions other than `'static`.
-    pub fn is_free(&self, r: Region<'_>) -> bool {
-        matches!(*r, ty::ReEarlyBound(_) | ty::ReFree(_))
-    }
-
-    /// True if `r` is a free region or static of the sort that this
-    /// free region map can be used with.
-    pub fn is_free_or_static(&self, r: Region<'_>) -> bool {
-        match *r {
-            ty::ReStatic => true,
-            _ => self.is_free(r),
-        }
-    }
-
     /// Computes the least-upper-bound of two free regions. In some
     /// cases, this is more conservative than necessary, in order to
     /// avoid making arbitrary choices. See
@@ -110,8 +96,8 @@ pub fn lub_free_regions(
         r_b: Region<'tcx>,
     ) -> Region<'tcx> {
         debug!("lub_free_regions(r_a={:?}, r_b={:?})", r_a, r_b);
-        assert!(self.is_free(r_a));
-        assert!(self.is_free(r_b));
+        assert!(r_a.is_free());
+        assert!(r_b.is_free());
         let result = if r_a == r_b {
             r_a
         } else {

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

@@ -47,7 +47,6 @@ pub(crate) fn resolve<'tcx>(
 #[derive(Clone)]
 pub struct LexicalRegionResolutions<'tcx> {
     pub(crate) values: IndexVec<RegionVid, VarValue<'tcx>>,
-    pub(crate) error_region: ty::Region<'tcx>,
 }
 
 #[derive(Copy, Clone, Debug)]
@@ -140,7 +139,6 @@ fn num_vars(&self) -> usize {
     /// empty region. The `expansion` phase will grow this larger.
     fn construct_var_data(&self, tcx: TyCtxt<'tcx>) -> LexicalRegionResolutions<'tcx> {
         LexicalRegionResolutions {
-            error_region: tcx.lifetimes.re_static,
             values: IndexVec::from_fn_n(
                 |vid| {
                     let vid_universe = self.var_infos[vid].universe;
@@ -310,7 +308,7 @@ fn sub_concrete_regions(&self, a: Region<'tcx>, b: Region<'tcx>) -> bool {
 
         // Check for the case where we know that `'b: 'static` -- in that case,
         // `a <= b` for all `a`.
-        let b_free_or_static = self.region_rels.free_regions.is_free_or_static(b);
+        let b_free_or_static = b.is_free_or_static();
         if b_free_or_static && sub_free_regions(tcx.lifetimes.re_static, b) {
             return true;
         }
@@ -320,7 +318,7 @@ fn sub_concrete_regions(&self, a: Region<'tcx>, b: Region<'tcx>) -> bool {
         // `lub` relationship defined below, since sometimes the "lub"
         // is actually the `postdom_upper_bound` (see
         // `TransitiveRelation` for more details).
-        let a_free_or_static = self.region_rels.free_regions.is_free_or_static(a);
+        let a_free_or_static = a.is_free_or_static();
         if a_free_or_static && b_free_or_static {
             return sub_free_regions(a, b);
         }
@@ -864,10 +862,7 @@ fn normalize<T>(&self, tcx: TyCtxt<'tcx>, value: T) -> T
     where
         T: TypeFoldable<'tcx>,
     {
-        tcx.fold_regions(value, |r, _db| match *r {
-            ty::ReVar(rid) => self.resolve_var(rid),
-            _ => r,
-        })
+        tcx.fold_regions(value, |r, _db| self.resolve_region(tcx, r))
     }
 
     fn value(&self, rid: RegionVid) -> &VarValue<'tcx> {
@@ -878,12 +873,19 @@ fn value_mut(&mut self, rid: RegionVid) -> &mut VarValue<'tcx> {
         &mut self.values[rid]
     }
 
-    pub fn resolve_var(&self, rid: RegionVid) -> ty::Region<'tcx> {
-        let result = match self.values[rid] {
-            VarValue::Value(r) => r,
-            VarValue::ErrorValue => self.error_region,
+    pub(crate) fn resolve_region(
+        &self,
+        tcx: TyCtxt<'tcx>,
+        r: ty::Region<'tcx>,
+    ) -> ty::Region<'tcx> {
+        let result = match *r {
+            ty::ReVar(rid) => match self.values[rid] {
+                VarValue::Value(r) => r,
+                VarValue::ErrorValue => tcx.lifetimes.re_static,
+            },
+            _ => r,
         };
-        debug!("resolve_var({:?}) = {:?}", rid, result);
+        debug!("resolve_region({:?}) = {:?}", r, result);
         result
     }
 }

compiler/rustc_infer/src/infer/mod.rs

@@ -466,9 +466,6 @@ pub enum NllRegionVariableOrigin {
     /// from a `for<'a> T` binder). Meant to represent "any region".
     Placeholder(ty::PlaceholderRegion),
 
-    /// The variable we create to represent `'empty(U0)`.
-    RootEmptyRegion,
-
     Existential {
         /// If this is true, then this variable was created to represent a lifetime
         /// bound in a `for` binder. For example, it might have been created to
@@ -1250,7 +1247,6 @@ pub fn skip_region_resolution(&self) {
         };
 
         let lexical_region_resolutions = LexicalRegionResolutions {
-            error_region: self.tcx.lifetimes.re_static,
             values: rustc_index::vec::IndexVec::from_elem_n(
                 crate::infer::lexical_region_resolve::VarValue::Value(self.tcx.lifetimes.re_erased),
                 var_infos.len(),

compiler/rustc_infer/src/infer/resolve.rs

@@ -206,13 +206,13 @@ fn try_fold_ty(&mut self, t: Ty<'tcx>) -> Result<Ty<'tcx>, Self::Error> {
 
     fn try_fold_region(&mut self, r: ty::Region<'tcx>) -> Result<ty::Region<'tcx>, Self::Error> {
         match *r {
-            ty::ReVar(rid) => Ok(self
+            ty::ReVar(_) => Ok(self
                 .infcx
                 .lexical_region_resolutions
                 .borrow()
                 .as_ref()
                 .expect("region resolution not performed")
-                .resolve_var(rid)),
+                .resolve_region(self.infcx.tcx, r)),
             _ => Ok(r),
         }
     }

compiler/rustc_interface/src/tests.rs

@@ -689,7 +689,6 @@ fn test_debugging_options_tracking_hash() {
     untracked!(span_debug, true);
     untracked!(span_free_formats, true);
     untracked!(temps_dir, Some(String::from("abc")));
-    untracked!(terminal_width, Some(80));
     untracked!(threads, 99);
     untracked!(time, true);
     untracked!(time_llvm_passes, true);

compiler/rustc_middle/src/mir/mod.rs

@@ -1048,6 +1048,8 @@ pub fn start_location(self) -> Location {
 ///////////////////////////////////////////////////////////////////////////
 // BasicBlockData
 
+/// Data for a basic block, including a list of its statements.
+///
 /// See [`BasicBlock`] for documentation on what basic blocks are at a high level.
 #[derive(Clone, Debug, TyEncodable, TyDecodable, HashStable, TypeFoldable, TypeVisitable)]
 pub struct BasicBlockData<'tcx> {
@@ -1079,7 +1081,7 @@ pub fn new(terminator: Option<Terminator<'tcx>>) -> BasicBlockData<'tcx> {
     /// Accessor for terminator.
     ///
     /// Terminator may not be None after construction of the basic block is complete. This accessor
-    /// provides a convenience way to reach the terminator.
+    /// provides a convenient way to reach the terminator.
     #[inline]
     pub fn terminator(&self) -> &Terminator<'tcx> {
         self.terminator.as_ref().expect("invalid terminator state")
@@ -1286,6 +1288,7 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 ///////////////////////////////////////////////////////////////////////////
 // Statements
 
+/// A statement in a basic block, including information about its source code.
 #[derive(Clone, TyEncodable, TyDecodable, HashStable, TypeFoldable, TypeVisitable)]
 pub struct Statement<'tcx> {
     pub source_info: SourceInfo,

compiler/rustc_middle/src/ty/sty.rs

@@ -1570,6 +1570,19 @@ pub fn free_region_binding_scope(self, tcx: TyCtxt<'_>) -> DefId {
             _ => bug!("free_region_binding_scope invoked on inappropriate region: {:?}", self),
         }
     }
+
+    /// True for free regions other than `'static`.
+    pub fn is_free(self) -> bool {
+        matches!(*self, ty::ReEarlyBound(_) | ty::ReFree(_))
+    }
+
+    /// True if `self` is a free region or static.
+    pub fn is_free_or_static(self) -> bool {
+        match *self {
+            ty::ReStatic => true,
+            _ => self.is_free(),
+        }
+    }
 }
 
 /// Type utilities

compiler/rustc_session/src/config.rs

@@ -726,6 +726,7 @@ fn default() -> Options {
             prints: Vec::new(),
             cg: Default::default(),
             error_format: ErrorOutputType::default(),
+            diagnostic_width: None,
             externs: Externs(BTreeMap::new()),
             crate_name: None,
             libs: Vec::new(),
@@ -1427,6 +1428,12 @@ pub fn rustc_optgroups() -> Vec<RustcOptGroup> {
                                  never  = never colorize output",
             "auto|always|never",
         ),
+        opt::opt_s(
+            "",
+            "diagnostic-width",
+            "Inform rustc of the width of the output so that diagnostics can be truncated to fit",
+            "WIDTH",
+        ),
         opt::multi_s(
             "",
             "remap-path-prefix",
@@ -2202,6 +2209,10 @@ pub fn build_session_options(matches: &getopts::Matches) -> Options {
 
     let error_format = parse_error_format(matches, color, json_rendered);
 
+    let diagnostic_width = matches.opt_get("diagnostic-width").unwrap_or_else(|_| {
+        early_error(error_format, "`--diagnostic-width` must be an positive integer");
+    });
+
     let unparsed_crate_types = matches.opt_strs("crate-type");
     let crate_types = parse_crate_types_from_list(unparsed_crate_types)
         .unwrap_or_else(|e| early_error(error_format, &e));
@@ -2474,6 +2485,7 @@ pub fn build_session_options(matches: &getopts::Matches) -> Options {
         prints,
         cg,
         error_format,
+        diagnostic_width,
         externs,
         unstable_features: UnstableFeatures::from_environment(crate_name.as_deref()),
         crate_name,

compiler/rustc_session/src/options.rs

@@ -170,6 +170,7 @@ pub struct Options {
 
         test: bool [TRACKED],
         error_format: ErrorOutputType [UNTRACKED],
+        diagnostic_width: Option<usize> [UNTRACKED],
 
         /// If `Some`, enable incremental compilation, using the given
         /// directory to store intermediate results.
@@ -1388,6 +1389,8 @@ pub(crate) fn parse_branch_protection(
         "panic strategy for out-of-memory handling"),
     osx_rpath_install_name: bool = (false, parse_bool, [TRACKED],
         "pass `-install_name @rpath/...` to the macOS linker (default: no)"),
+    diagnostic_width: Option<usize> = (None, parse_opt_number, [UNTRACKED],
+        "set the current output width for diagnostic truncation"),
     panic_abort_tests: bool = (false, parse_bool, [TRACKED],
         "support compiling tests with panic=abort (default: no)"),
     panic_in_drop: PanicStrategy = (PanicStrategy::Unwind, parse_panic_strategy, [TRACKED],
@@ -1514,8 +1517,6 @@ pub(crate) fn parse_branch_protection(
         "show extended diagnostic help (default: no)"),
     temps_dir: Option<String> = (None, parse_opt_string, [UNTRACKED],
         "the directory the intermediate files are written to"),
-    terminal_width: Option<usize> = (None, parse_opt_number, [UNTRACKED],
-        "set the current terminal width"),
     // Diagnostics are considered side-effects of a query (see `QuerySideEffects`) and are saved
     // alongside query results and changes to translation options can affect diagnostics - so
     // translation options should be tracked.

compiler/rustc_session/src/session.rs

@@ -1162,7 +1162,7 @@ fn default_emitter(
                         fallback_bundle,
                         short,
                         sopts.debugging_opts.teach,
-                        sopts.debugging_opts.terminal_width,
+                        sopts.diagnostic_width,
                         macro_backtrace,
                     ),
                     Some(dst) => EmitterWriter::new(
@@ -1173,7 +1173,7 @@ fn default_emitter(
                         short,
                         false, // no teach messages when writing to a buffer
                         false, // no colors when writing to a buffer
-                        None,  // no terminal width
+                        None,  // no diagnostic width
                         macro_backtrace,
                     ),
                 };
@@ -1188,7 +1188,7 @@ fn default_emitter(
                 fallback_bundle,
                 pretty,
                 json_rendered,
-                sopts.debugging_opts.terminal_width,
+                sopts.diagnostic_width,
                 macro_backtrace,
             )
             .ui_testing(sopts.debugging_opts.ui_testing),
@@ -1202,7 +1202,7 @@ fn default_emitter(
                 fallback_bundle,
                 pretty,
                 json_rendered,
-                sopts.debugging_opts.terminal_width,
+                sopts.diagnostic_width,
                 macro_backtrace,
             )
             .ui_testing(sopts.debugging_opts.ui_testing),

compiler/rustc_trait_selection/src/lib.rs

@@ -37,5 +37,4 @@
 
 pub mod autoderef;
 pub mod infer;
-pub mod opaque_types;
 pub mod traits;

compiler/rustc_trait_selection/src/traits/wf.rs

 use crate::infer::InferCtxt;
-use crate::opaque_types::required_region_bounds;
 use crate::traits;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
@@ -810,3 +809,63 @@ pub fn object_region_bounds<'tcx>(
 
     required_region_bounds(tcx, open_ty, predicates)
 }
+
+/// Given a set of predicates that apply to an object type, returns
+/// the region bounds that the (erased) `Self` type must
+/// outlive. Precisely *because* the `Self` type is erased, the
+/// parameter `erased_self_ty` must be supplied to indicate what type
+/// has been used to represent `Self` in the predicates
+/// themselves. This should really be a unique type; `FreshTy(0)` is a
+/// popular choice.
+///
+/// N.B., in some cases, particularly around higher-ranked bounds,
+/// this function returns a kind of conservative approximation.
+/// That is, all regions returned by this function are definitely
+/// required, but there may be other region bounds that are not
+/// returned, as well as requirements like `for<'a> T: 'a`.
+///
+/// Requires that trait definitions have been processed so that we can
+/// elaborate predicates and walk supertraits.
+#[instrument(skip(tcx, predicates), level = "debug")]
+pub(crate) fn required_region_bounds<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    erased_self_ty: Ty<'tcx>,
+    predicates: impl Iterator<Item = ty::Predicate<'tcx>>,
+) -> Vec<ty::Region<'tcx>> {
+    assert!(!erased_self_ty.has_escaping_bound_vars());
+
+    traits::elaborate_predicates(tcx, predicates)
+        .filter_map(|obligation| {
+            debug!(?obligation);
+            match obligation.predicate.kind().skip_binder() {
+                ty::PredicateKind::Projection(..)
+                | ty::PredicateKind::Trait(..)
+                | ty::PredicateKind::Subtype(..)
+                | ty::PredicateKind::Coerce(..)
+                | ty::PredicateKind::WellFormed(..)
+                | ty::PredicateKind::ObjectSafe(..)
+                | ty::PredicateKind::ClosureKind(..)
+                | ty::PredicateKind::RegionOutlives(..)
+                | ty::PredicateKind::ConstEvaluatable(..)
+                | ty::PredicateKind::ConstEquate(..)
+                | ty::PredicateKind::TypeWellFormedFromEnv(..) => None,
+                ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(ref t, ref r)) => {
+                    // Search for a bound of the form `erased_self_ty
+                    // : 'a`, but be wary of something like `for<'a>
+                    // erased_self_ty : 'a` (we interpret a
+                    // higher-ranked bound like that as 'static,
+                    // though at present the code in `fulfill.rs`
+                    // considers such bounds to be unsatisfiable, so
+                    // it's kind of a moot point since you could never
+                    // construct such an object, but this seems
+                    // correct even if that code changes).
+                    if t == &erased_self_ty && !r.has_escaping_bound_vars() {
+                        Some(*r)
+                    } else {
+                        None
+                    }
+                }
+            }
+        })
+        .collect()
+}

library/core/src/future/into_future.rs

@@ -13,8 +13,6 @@
 /// on all futures.
 ///
 /// ```no_run
-/// #![feature(into_future)]
-///
 /// use std::future::IntoFuture;
 ///
 /// # async fn foo() {
@@ -33,8 +31,6 @@
 /// multiple times before being `.await`ed.
 ///
 /// ```rust
-/// #![feature(into_future)]
-///
 /// use std::future::{ready, Ready, IntoFuture};
 ///
 /// /// Eventually multiply two numbers
@@ -91,8 +87,6 @@
 /// `IntoFuture::into_future` to obtain an instance of `Future`:
 ///
 /// ```rust
-/// #![feature(into_future)]
-///
 /// use std::future::IntoFuture;
 ///
 /// /// Convert the output of a future to a string.
@@ -104,14 +98,14 @@
 ///     format!("{:?}", fut.await)
 /// }
 /// ```
-#[unstable(feature = "into_future", issue = "67644")]
+#[stable(feature = "into_future", since = "1.64.0")]
 pub trait IntoFuture {
     /// The output that the future will produce on completion.
-    #[unstable(feature = "into_future", issue = "67644")]
+    #[stable(feature = "into_future", since = "1.64.0")]
     type Output;
 
     /// Which kind of future are we turning this into?
-    #[unstable(feature = "into_future", issue = "67644")]
+    #[stable(feature = "into_future", since = "1.64.0")]
     type IntoFuture: Future<Output = Self::Output>;
 
     /// Creates a future from a value.
@@ -121,8 +115,6 @@ pub trait IntoFuture {
     /// Basic usage:
     ///
     /// ```no_run
-    /// #![feature(into_future)]
-    ///
     /// use std::future::IntoFuture;
     ///
     /// # async fn foo() {
@@ -131,12 +123,12 @@ pub trait IntoFuture {
     /// assert_eq!("meow", fut.await);
     /// # }
     /// ```
-    #[unstable(feature = "into_future", issue = "67644")]
+    #[stable(feature = "into_future", since = "1.64.0")]
     #[lang = "into_future"]
     fn into_future(self) -> Self::IntoFuture;
 }
 
-#[unstable(feature = "into_future", issue = "67644")]
+#[stable(feature = "into_future", since = "1.64.0")]
 impl<F: Future> IntoFuture for F {
     type Output = F::Output;
     type IntoFuture = F;

library/core/src/future/mod.rs

@@ -29,7 +29,7 @@
 #[unstable(feature = "future_join", issue = "91642")]
 pub use self::join::join;
 
-#[unstable(feature = "into_future", issue = "67644")]
+#[stable(feature = "into_future", since = "1.64.0")]
 pub use into_future::IntoFuture;
 
 #[stable(feature = "future_readiness_fns", since = "1.48.0")]

src/bootstrap/builder.rs

@@ -949,6 +949,7 @@ pub(crate) fn fix_bin_or_dylib(&self, fname: &Path) {
     }
 
     pub(crate) fn download_component(&self, url: &str, dest_path: &Path, help_on_error: &str) {
+        self.verbose(&format!("download {url}"));
         // Use a temporary file in case we crash while downloading, to avoid a corrupt download in cache/.
         let tempfile = self.tempdir().join(dest_path.file_name().unwrap());
         // While bootstrap itself only supports http and https downloads, downstream forks might

src/bootstrap/config.rs

@@ -1558,7 +1558,7 @@ fn download_ci_rustc(builder: &Builder<'_>, commit: &str) {
         builder.fix_bin_or_dylib(&bin_root.join("bin").join("rustc"));
         builder.fix_bin_or_dylib(&bin_root.join("bin").join("rustdoc"));
         let lib_dir = bin_root.join("lib");
-        for lib in t!(fs::read_dir(lib_dir)) {
+        for lib in t!(fs::read_dir(&lib_dir), lib_dir.display().to_string()) {
             let lib = t!(lib);
             if lib.path().extension() == Some(OsStr::new("so")) {
                 builder.fix_bin_or_dylib(&lib.path());
@@ -1634,6 +1634,7 @@ fn download_component(
         }
         Some(sha256)
     } else if tarball.exists() {
+        builder.unpack(&tarball, &bin_root, prefix);
         return;
     } else {
         None

src/librustdoc/config.rs

@@ -73,6 +73,8 @@ pub(crate) struct Options {
     pub(crate) proc_macro_crate: bool,
     /// How to format errors and warnings.
     pub(crate) error_format: ErrorOutputType,
+    /// Width of output buffer to truncate errors appropriately.
+    pub(crate) diagnostic_width: Option<usize>,
     /// Library search paths to hand to the compiler.
     pub(crate) libs: Vec<SearchPath>,
     /// Library search paths strings to hand to the compiler.
@@ -331,11 +333,12 @@ pub(crate) fn from_matches(
         let config::JsonConfig { json_rendered, json_unused_externs, .. } =
             config::parse_json(matches);
         let error_format = config::parse_error_format(matches, color, json_rendered);
+        let diagnostic_width = matches.opt_get("diagnostic-width").unwrap_or_default();
 
         let codegen_options = CodegenOptions::build(matches, error_format);
         let debugging_opts = DebuggingOptions::build(matches, error_format);
 
-        let diag = new_handler(error_format, None, &debugging_opts);
+        let diag = new_handler(error_format, None, diagnostic_width, &debugging_opts);
 
         // check for deprecated options
         check_deprecated_options(matches, &diag);
@@ -699,6 +702,7 @@ fn println_condition(condition: Condition) {
             input,
             proc_macro_crate,
             error_format,
+            diagnostic_width,
             libs,
             lib_strs,
             externs,

src/librustdoc/core.rs

@@ -154,6 +154,7 @@ pub(crate) fn with_all_trait_impls(&mut self, f: impl FnOnce(&mut Self, &[DefId]
 pub(crate) fn new_handler(
     error_format: ErrorOutputType,
     source_map: Option<Lrc<source_map::SourceMap>>,
+    diagnostic_width: Option<usize>,
     debugging_opts: &DebuggingOptions,
 ) -> rustc_errors::Handler {
     let fallback_bundle =
@@ -169,7 +170,7 @@ pub(crate) fn new_handler(
                     fallback_bundle,
                     short,
                     debugging_opts.teach,
-                    debugging_opts.terminal_width,
+                    diagnostic_width,
                     false,
                 )
                 .ui_testing(debugging_opts.ui_testing),
@@ -187,7 +188,7 @@ pub(crate) fn new_handler(
                     fallback_bundle,
                     pretty,
                     json_rendered,
-                    debugging_opts.terminal_width,
+                    diagnostic_width,
                     false,
                 )
                 .ui_testing(debugging_opts.ui_testing),
@@ -208,6 +209,7 @@ pub(crate) fn create_config(
         crate_name,
         proc_macro_crate,
         error_format,
+        diagnostic_width,
         libs,
         externs,
         mut cfgs,
@@ -266,6 +268,7 @@ pub(crate) fn create_config(
         actually_rustdoc: true,
         debugging_opts,
         error_format,
+        diagnostic_width,
         edition,
         describe_lints,
         crate_name,

src/librustdoc/lib.rs

@@ -462,6 +462,14 @@ fn opts() -> Vec<RustcOptGroup> {
                 "human|json|short",
             )
         }),
+        unstable("diagnostic-width", |o| {
+            o.optopt(
+                "",
+                "diagnostic-width",
+                "Provide width of the output for truncated error messages",
+                "WIDTH",
+            )
+        }),
         stable("json", |o| {
             o.optopt("", "json", "Configure the structure of JSON diagnostics", "CONFIG")
         }),
@@ -733,7 +741,12 @@ fn run_renderer<'tcx, T: formats::FormatRenderer<'tcx>>(
 }
 
 fn main_options(options: config::Options) -> MainResult {
-    let diag = core::new_handler(options.error_format, None, &options.debugging_opts);
+    let diag = core::new_handler(
+        options.error_format,
+        None,
+        options.diagnostic_width,
+        &options.debugging_opts,
+    );
 
     match (options.should_test, options.markdown_input()) {
         (true, true) => return wrap_return(&diag, markdown::test(options)),

src/test/run-make/issue-88756-default-output/output-default.stdout

@@ -110,6 +110,9 @@ Options:
                         never = never colorize output
         --error-format human|json|short
                         How errors and other messages are produced
+        --diagnostic-width WIDTH
+                        Provide width of the output for truncated error
+                        messages
         --json CONFIG   Configure the structure of JSON diagnostics
         --disable-minification 
                         Disable minification applied on JS files

src/test/rustdoc-ui/diagnostic-width.rs

+// compile-flags: -Zunstable-options --diagnostic-width=10
+#![deny(rustdoc::bare_urls)]
+
+/// This is a long line that contains a http://link.com
+pub struct Foo; //~^ ERROR

src/test/rustdoc-ui/diagnostic-width.stderr

+error: this URL is not a hyperlink
+  --> $DIR/diagnostic-width.rs:4:41
+   |
+LL | ... a http://link.com
+   |       ^^^^^^^^^^^^^^^ help: use an automatic link instead: `<http://link.com>`
+   |
+note: the lint level is defined here
+  --> $DIR/diagnostic-width.rs:2:9
+   |
+LL | ...ny(rustdoc::bare_url...
+   |       ^^^^^^^^^^^^^^^^^^
+   = note: bare URLs are not automatically turned into clickable links
+
+error: aborting due to previous error
+

src/test/ui/async-await/await-into-future.rs

 // run-pass
 // aux-build: issue-72470-lib.rs
 // edition:2021
-#![feature(into_future)]
-
 extern crate issue_72470_lib;
 use std::{future::{Future, IntoFuture}, pin::Pin};
 

src/test/ui/terminal-width/flag-human.rs → src/test/ui/diagnostic-width/flag-human.rs

-// compile-flags: -Z terminal-width=20
+// compile-flags: --diagnostic-width=20
 
-// This test checks that `-Z terminal-width` effects the human error output by restricting it to an
+// This test checks that `-Z output-width` effects the human error output by restricting it to an
 // arbitrarily low value so that the effect is visible.
 
 fn main() {

src/test/ui/terminal-width/flag-json.rs → src/test/ui/diagnostic-width/flag-json.rs

-// compile-flags: -Z terminal-width=20 --error-format=json
+// compile-flags: --diagnostic-width=20 --error-format=json
 
-// This test checks that `-Z terminal-width` effects the JSON error output by restricting it to an
+// This test checks that `-Z output-width` effects the JSON error output by restricting it to an
 // arbitrarily low value so that the effect is visible.
 
 fn main() {

src/test/ui/terminal-width/flag-json.stderr → src/test/ui/diagnostic-width/flag-json.stderr

@@ -24,7 +24,7 @@ This error occurs when an expression was used in a place where the compiler
 expected an expression of a different type. It can occur in several cases, the
 most common being when calling a function and passing an argument which has a
 different type than the matching type in the function declaration.
-"},"level":"error","spans":[{"file_name":"$DIR/flag-json.rs","byte_start":244,"byte_end":246,"line_start":7,"line_end":7,"column_start":17,"column_end":19,"is_primary":true,"text":[{"text":"    let _: () = 42;","highlight_start":17,"highlight_end":19}],"label":"expected `()`, found integer","suggested_replacement":null,"suggestion_applicability":null,"expansion":null},{"file_name":"$DIR/flag-json.rs","byte_start":239,"byte_end":241,"line_start":7,"line_end":7,"column_start":12,"column_end":14,"is_primary":false,"text":[{"text":"    let _: () = 42;","highlight_start":12,"highlight_end":14}],"label":"expected due to this","suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[],"rendered":"error[E0308]: mismatched types
+"},"level":"error","spans":[{"file_name":"$DIR/flag-json.rs","byte_start":243,"byte_end":245,"line_start":7,"line_end":7,"column_start":17,"column_end":19,"is_primary":true,"text":[{"text":"    let _: () = 42;","highlight_start":17,"highlight_end":19}],"label":"expected `()`, found integer","suggested_replacement":null,"suggestion_applicability":null,"expansion":null},{"file_name":"$DIR/flag-json.rs","byte_start":238,"byte_end":240,"line_start":7,"line_end":7,"column_start":12,"column_end":14,"is_primary":false,"text":[{"text":"    let _: () = 42;","highlight_start":12,"highlight_end":14}],"label":"expected due to this","suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[],"rendered":"error[E0308]: mismatched types
   --> $DIR/flag-json.rs:7:17
    |
 LL | ..._: () = 42;

src/tools/clippy/clippy_lints/src/misc.rs

@@ -301,7 +301,7 @@ fn in_attributes_expansion(expr: &Expr<'_>) -> bool {
     use rustc_span::hygiene::MacroKind;
     if expr.span.from_expansion() {
         let data = expr.span.ctxt().outer_expn_data();
-        matches!(data.kind, ExpnKind::Macro(MacroKind::Attr, _))
+        matches!(data.kind, ExpnKind::Macro(MacroKind::Attr|MacroKind::Derive, _))
     } else {
         false
     }

src/tools/clippy/tests/ui/used_underscore_binding.rs

@@ -44,6 +44,12 @@ fn in_struct_field() {
     s._underscore_field += 1;
 }
 
+/// Tests that we do not lint if the struct field is used in code created with derive.
+#[derive(Clone, Debug)]
+pub struct UnderscoreInStruct {
+    _foo: u32,
+}
+
 /// Tests that we do not lint if the underscore is not a prefix
 fn non_prefix_underscore(some_foo: u32) -> u32 {
     some_foo + 1

src/tools/clippy/tests/ui/used_underscore_binding.stderr

@@ -31,7 +31,7 @@ LL |     s._underscore_field += 1;
    |     ^^^^^^^^^^^^^^^^^^^
 
 error: used binding `_i` which is prefixed with an underscore. A leading underscore signals that a binding will not be used
-  --> $DIR/used_underscore_binding.rs:99:16
+  --> $DIR/used_underscore_binding.rs:105:16
    |
 LL |         uses_i(_i);
    |                ^^