Rollup of 8 pull requests

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -676,17 +676,18 @@ fn link_dwarf_object<'a>(
             thorin::MissingReferencedObjectBehaviour::Skip,
         )?;
 
-        let output = package.finish()?.write()?;
-        let mut output_stream = BufWriter::new(
+        let output_stream = BufWriter::new(
             OpenOptions::new()
                 .read(true)
                 .write(true)
                 .create(true)
                 .truncate(true)
                 .open(dwp_out_filename)?,
         );
-        output_stream.write_all(&output)?;
-        output_stream.flush()?;
+        let mut output_stream = object::write::StreamingBuffer::new(output_stream);
+        package.finish()?.emit(&mut output_stream)?;
+        output_stream.result()?;
+        output_stream.into_inner().flush()?;
 
         Ok(())
     }) {

compiler/rustc_expand/src/base.rs

@@ -676,8 +676,13 @@ pub enum SyntaxExtensionKind {
 
     /// A token-based derive macro.
     Derive(
-        /// An expander with signature TokenStream -> TokenStream (not yet).
+        /// An expander with signature TokenStream -> TokenStream.
         /// The produced TokenSteam is appended to the input TokenSteam.
+        ///
+        /// FIXME: The text above describes how this should work. Currently it
+        /// is handled identically to `LegacyDerive`. It should be migrated to
+        /// a token-based representation like `Bang` and `Attr`, instead of
+        /// using `MultiItemModifier`.
         Box<dyn MultiItemModifier + sync::Sync + sync::Send>,
     ),
 

compiler/rustc_hir_typeck/src/method/probe.rs

@@ -31,6 +31,7 @@ use rustc_span::lev_distance::{
 use rustc_span::symbol::sym;
 use rustc_span::{symbol::Ident, Span, Symbol, DUMMY_SP};
 use rustc_trait_selection::autoderef::{self, Autoderef};
+use rustc_trait_selection::infer::InferCtxtExt as _;
 use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt;
 use rustc_trait_selection::traits::query::method_autoderef::MethodAutoderefBadTy;
 use rustc_trait_selection::traits::query::method_autoderef::{
@@ -716,9 +717,10 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
             // maybe shouldn't include `Param`s, but rather fresh variables or be canonicalized,
             // see issue #89650
             let cause = traits::ObligationCause::misc(self.span, self.body_id);
-            let selcx = &mut traits::SelectionContext::new(self.fcx);
-            let traits::Normalized { value: xform_self_ty, obligations } =
-                traits::normalize(selcx, self.param_env, cause, xform_self_ty);
+            let InferOk { value: xform_self_ty, obligations } = self
+                .fcx
+                .partially_normalize_associated_types_in(cause, self.param_env, xform_self_ty);
+
             debug!(
                 "assemble_inherent_impl_probe after normalization: xform_self_ty = {:?}/{:?}",
                 xform_self_ty, xform_ret_ty
@@ -1490,7 +1492,6 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
             let mut xform_ret_ty = probe.xform_ret_ty;
             debug!(?xform_ret_ty);
 
-            let selcx = &mut traits::SelectionContext::new(self);
             let cause = traits::ObligationCause::misc(self.span, self.body_id);
 
             let mut parent_pred = None;
@@ -1504,19 +1505,28 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
                     // `xform_ret_ty` hasn't been normalized yet, only `xform_self_ty`,
                     // see the reasons mentioned in the comments in `assemble_inherent_impl_probe`
                     // for why this is necessary
-                    let traits::Normalized {
+                    let InferOk {
                         value: normalized_xform_ret_ty,
                         obligations: normalization_obligations,
-                    } = traits::normalize(selcx, self.param_env, cause.clone(), probe.xform_ret_ty);
+                    } = self.fcx.partially_normalize_associated_types_in(
+                        cause.clone(),
+                        self.param_env,
+                        probe.xform_ret_ty,
+                    );
                     xform_ret_ty = normalized_xform_ret_ty;
                     debug!("xform_ret_ty after normalization: {:?}", xform_ret_ty);
 
                     // Check whether the impl imposes obligations we have to worry about.
                     let impl_def_id = probe.item.container_id(self.tcx);
                     let impl_bounds = self.tcx.predicates_of(impl_def_id);
                     let impl_bounds = impl_bounds.instantiate(self.tcx, substs);
-                    let traits::Normalized { value: impl_bounds, obligations: norm_obligations } =
-                        traits::normalize(selcx, self.param_env, cause.clone(), impl_bounds);
+
+                    let InferOk { value: impl_bounds, obligations: norm_obligations } =
+                        self.fcx.partially_normalize_associated_types_in(
+                            cause.clone(),
+                            self.param_env,
+                            impl_bounds,
+                        );
 
                     // Convert the bounds into obligations.
                     let impl_obligations = traits::predicates_for_generics(

compiler/rustc_middle/src/traits/mod.rs

@@ -651,12 +651,6 @@ pub enum ImplSource<'tcx, N> {
     /// Same as above, but for a function pointer type with the given signature.
     FnPointer(ImplSourceFnPointerData<'tcx, N>),
 
-    /// ImplSource for a builtin `DeterminantKind` trait implementation.
-    DiscriminantKind(ImplSourceDiscriminantKindData),
-
-    /// ImplSource for a builtin `Pointee` trait implementation.
-    Pointee(ImplSourcePointeeData),
-
     /// ImplSource automatically generated for a generator.
     Generator(ImplSourceGeneratorData<'tcx, N>),
 
@@ -682,8 +676,6 @@ impl<'tcx, N> ImplSource<'tcx, N> {
             ImplSource::Future(c) => c.nested,
             ImplSource::Object(d) => d.nested,
             ImplSource::FnPointer(d) => d.nested,
-            ImplSource::DiscriminantKind(ImplSourceDiscriminantKindData)
-            | ImplSource::Pointee(ImplSourcePointeeData) => vec![],
             ImplSource::TraitAlias(d) => d.nested,
             ImplSource::TraitUpcasting(d) => d.nested,
             ImplSource::ConstDestruct(i) => i.nested,
@@ -701,8 +693,6 @@ impl<'tcx, N> ImplSource<'tcx, N> {
             ImplSource::Future(c) => &c.nested,
             ImplSource::Object(d) => &d.nested,
             ImplSource::FnPointer(d) => &d.nested,
-            ImplSource::DiscriminantKind(ImplSourceDiscriminantKindData)
-            | ImplSource::Pointee(ImplSourcePointeeData) => &[],
             ImplSource::TraitAlias(d) => &d.nested,
             ImplSource::TraitUpcasting(d) => &d.nested,
             ImplSource::ConstDestruct(i) => &i.nested,
@@ -751,12 +741,6 @@ impl<'tcx, N> ImplSource<'tcx, N> {
                 fn_ty: p.fn_ty,
                 nested: p.nested.into_iter().map(f).collect(),
             }),
-            ImplSource::DiscriminantKind(ImplSourceDiscriminantKindData) => {
-                ImplSource::DiscriminantKind(ImplSourceDiscriminantKindData)
-            }
-            ImplSource::Pointee(ImplSourcePointeeData) => {
-                ImplSource::Pointee(ImplSourcePointeeData)
-            }
             ImplSource::TraitAlias(d) => ImplSource::TraitAlias(ImplSourceTraitAliasData {
                 alias_def_id: d.alias_def_id,
                 substs: d.substs,
@@ -876,13 +860,6 @@ pub struct ImplSourceFnPointerData<'tcx, N> {
     pub nested: Vec<N>,
 }
 
-// FIXME(@lcnr): This should be  refactored and merged with other builtin vtables.
-#[derive(Clone, Debug, PartialEq, Eq, TyEncodable, TyDecodable, HashStable)]
-pub struct ImplSourceDiscriminantKindData;
-
-#[derive(Clone, Debug, PartialEq, Eq, TyEncodable, TyDecodable, HashStable)]
-pub struct ImplSourcePointeeData;
-
 #[derive(Clone, PartialEq, Eq, TyEncodable, TyDecodable, HashStable, Lift)]
 #[derive(TypeFoldable, TypeVisitable)]
 pub struct ImplSourceConstDestructData<N> {

compiler/rustc_middle/src/traits/select.rs

@@ -105,6 +105,12 @@ pub type EvaluationCache<'tcx> = Cache<
 /// parameter environment.
 #[derive(PartialEq, Eq, Debug, Clone, TypeFoldable, TypeVisitable)]
 pub enum SelectionCandidate<'tcx> {
+    /// A builtin implementation for some specific traits, used in cases
+    /// where we cannot rely an ordinary library implementations.
+    ///
+    /// The most notable examples are `sized`, `Copy` and `Clone`. This is also
+    /// used for the `DiscriminantKind` and `Pointee` trait, both of which have
+    /// an associated type.
     BuiltinCandidate {
         /// `false` if there are no *further* obligations.
         has_nested: bool,
@@ -141,12 +147,6 @@ pub enum SelectionCandidate<'tcx> {
         is_const: bool,
     },
 
-    /// Builtin implementation of `DiscriminantKind`.
-    DiscriminantKindCandidate,
-
-    /// Builtin implementation of `Pointee`.
-    PointeeCandidate,
-
     TraitAliasCandidate,
 
     /// Matching `dyn Trait` with a supertrait of `Trait`. The index is the

compiler/rustc_middle/src/traits/structural_impls.rs

@@ -19,10 +19,6 @@ impl<'tcx, N: fmt::Debug> fmt::Debug for traits::ImplSource<'tcx, N> {
 
             super::ImplSource::FnPointer(ref d) => write!(f, "({:?})", d),
 
-            super::ImplSource::DiscriminantKind(ref d) => write!(f, "{:?}", d),
-
-            super::ImplSource::Pointee(ref d) => write!(f, "{:?}", d),
-
             super::ImplSource::Object(ref d) => write!(f, "{:?}", d),
 
             super::ImplSource::Param(ref n, ct) => {
@@ -137,11 +133,3 @@ impl<N: fmt::Debug> fmt::Debug for traits::ImplSourceConstDestructData<N> {
         write!(f, "ImplSourceConstDestructData(nested={:?})", self.nested)
     }
 }
-
-///////////////////////////////////////////////////////////////////////////
-// Lift implementations
-
-TrivialTypeTraversalAndLiftImpls! {
-    super::ImplSourceDiscriminantKindData,
-    super::ImplSourcePointeeData,
-}

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

@@ -9,6 +9,7 @@ use super::{
 };
 use crate::infer::error_reporting::{TyCategory, TypeAnnotationNeeded as ErrorCode};
 use crate::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
+use crate::infer::InferCtxtExt as _;
 use crate::infer::{self, InferCtxt, TyCtxtInferExt};
 use crate::traits::query::evaluate_obligation::InferCtxtExt as _;
 use crate::traits::query::normalize::AtExt as _;
@@ -28,7 +29,7 @@ use rustc_hir::GenericParam;
 use rustc_hir::Item;
 use rustc_hir::Node;
 use rustc_infer::infer::error_reporting::TypeErrCtxt;
-use rustc_infer::infer::TypeTrace;
+use rustc_infer::infer::{InferOk, TypeTrace};
 use rustc_middle::traits::select::OverflowError;
 use rustc_middle::ty::abstract_const::NotConstEvaluatable;
 use rustc_middle::ty::error::ExpectedFound;
@@ -2525,18 +2526,15 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
         }
 
         self.probe(|_| {
-            let mut selcx = SelectionContext::new(self);
-
             let cleaned_pred =
                 pred.fold_with(&mut ParamToVarFolder { infcx: self, var_map: Default::default() });
 
-            let cleaned_pred = super::project::normalize(
-                &mut selcx,
-                param_env,
-                ObligationCause::dummy(),
-                cleaned_pred,
-            )
-            .value;
+            let InferOk { value: cleaned_pred, .. } =
+                self.infcx.partially_normalize_associated_types_in(
+                    ObligationCause::dummy(),
+                    param_env,
+                    cleaned_pred,
+                );
 
             let obligation =
                 Obligation::new(self.tcx, ObligationCause::dummy(), param_env, cleaned_pred);

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

@@ -1,11 +1,7 @@
-use super::{
-    DefIdOrName, Obligation, ObligationCause, ObligationCauseCode, PredicateObligation,
-    SelectionContext,
-};
+use super::{DefIdOrName, Obligation, ObligationCause, ObligationCauseCode, PredicateObligation};
 
 use crate::autoderef::Autoderef;
 use crate::infer::InferCtxt;
-use crate::traits::normalize_to;
 
 use hir::def::CtorOf;
 use hir::HirId;
@@ -23,7 +19,7 @@ use rustc_hir::lang_items::LangItem;
 use rustc_hir::{AsyncGeneratorKind, GeneratorKind, Node};
 use rustc_infer::infer::error_reporting::TypeErrCtxt;
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
-use rustc_infer::infer::LateBoundRegionConversionTime;
+use rustc_infer::infer::{InferOk, LateBoundRegionConversionTime};
 use rustc_middle::hir::map;
 use rustc_middle::ty::{
     self, suggest_arbitrary_trait_bound, suggest_constraining_type_param, AdtKind, DefIdTree,
@@ -2979,13 +2975,12 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                         self.tcx.mk_substs_trait(trait_pred.self_ty(), []),
                     )
                 });
-                let projection_ty = normalize_to(
-                    &mut SelectionContext::new(self),
-                    obligation.param_env,
-                    obligation.cause.clone(),
-                    projection_ty,
-                    &mut vec![],
-                );
+                let InferOk { value: projection_ty, .. } = self
+                    .partially_normalize_associated_types_in(
+                        obligation.cause.clone(),
+                        obligation.param_env,
+                        projection_ty,
+                    );
 
                 debug!(
                     normalized_projection_type = ?self.resolve_vars_if_possible(projection_ty)