Auto merge of #110458 - matthiaskrgr:rollup-1xcxmgc, r=matthiaskrgr

Rollup of 9 pull requests

Successful merges:

 - #104055 (Migrate diagnostics in `rustc_borrowck`)
 - #110257 (fix false positives for `unused_parens` around unary and binary operations)
 - #110313 (allow `repr(align = x)` on inherent methods)
 - #110337 (Correct default value for default-linker-libraries)
 - #110386 (Clean up traversal macros)
 - #110394 (Various minor Idx-related tweaks)
 - #110425 (Encode def span for `ConstParam`)
 - #110434 (Check freeze with right param-env in `deduced_param_attrs`)
 - #110455 (tests: adapt for LLVM change 5b386b864c7619897c51a1da97d78f1cf6f3eff6)

Failed merges:

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

7 files changed, 30 insertions, 41 deletions

diff --git a/compiler/rustc_middle/src/infer/canonical.rs b/compiler/rustc_middle/src/infer/canonical.rs
index e63121475a1..c4e41e00520 100644
--- a/compiler/rustc_middle/src/infer/canonical.rs
+++ b/compiler/rustc_middle/src/infer/canonical.rs
@@ -392,10 +392,8 @@ pub type QueryOutlivesConstraint<'tcx> =
     (ty::OutlivesPredicate<GenericArg<'tcx>, Region<'tcx>>, ConstraintCategory<'tcx>);
 
 TrivialTypeTraversalAndLiftImpls! {
-    for <'tcx> {
-        crate::infer::canonical::Certainty,
-        crate::infer::canonical::CanonicalTyVarKind,
-    }
+    crate::infer::canonical::Certainty,
+    crate::infer::canonical::CanonicalTyVarKind,
 }
 
 impl<'tcx> CanonicalVarValues<'tcx> {
diff --git a/compiler/rustc_middle/src/macros.rs b/compiler/rustc_middle/src/macros.rs
index 89014f62d4d..cd1c6c330bc 100644
--- a/compiler/rustc_middle/src/macros.rs
+++ b/compiler/rustc_middle/src/macros.rs
@@ -43,34 +43,26 @@ macro_rules! span_bug {
 
 #[macro_export]
 macro_rules! CloneLiftImpls {
-    (for <$tcx:lifetime> { $($ty:ty,)+ }) => {
+    ($($ty:ty,)+) => {
         $(
-            impl<$tcx> $crate::ty::Lift<$tcx> for $ty {
+            impl<'tcx> $crate::ty::Lift<'tcx> for $ty {
                 type Lifted = Self;
-                fn lift_to_tcx(self, _: $crate::ty::TyCtxt<$tcx>) -> Option<Self> {
+                fn lift_to_tcx(self, _: $crate::ty::TyCtxt<'tcx>) -> Option<Self> {
                     Some(self)
                 }
             }
         )+
     };
-
-    ($($ty:ty,)+) => {
-        CloneLiftImpls! {
-            for <'tcx> {
-                $($ty,)+
-            }
-        }
-    };
 }
 
 /// Used for types that are `Copy` and which **do not care arena
 /// allocated data** (i.e., don't need to be folded).
 #[macro_export]
 macro_rules! TrivialTypeTraversalImpls {
-    (for <$tcx:lifetime> { $($ty:ty,)+ }) => {
+    ($($ty:ty,)+) => {
         $(
-            impl<$tcx> $crate::ty::fold::TypeFoldable<$crate::ty::TyCtxt<$tcx>> for $ty {
-                fn try_fold_with<F: $crate::ty::fold::FallibleTypeFolder<$crate::ty::TyCtxt<$tcx>>>(
+            impl<'tcx> $crate::ty::fold::TypeFoldable<$crate::ty::TyCtxt<'tcx>> for $ty {
+                fn try_fold_with<F: $crate::ty::fold::FallibleTypeFolder<$crate::ty::TyCtxt<'tcx>>>(
                     self,
                     _: &mut F,
                 ) -> ::std::result::Result<Self, F::Error> {
@@ -78,7 +70,7 @@ macro_rules! TrivialTypeTraversalImpls {
                 }
 
                 #[inline]
-                fn fold_with<F: $crate::ty::fold::TypeFolder<$crate::ty::TyCtxt<$tcx>>>(
+                fn fold_with<F: $crate::ty::fold::TypeFolder<$crate::ty::TyCtxt<'tcx>>>(
                     self,
                     _: &mut F,
                 ) -> Self {
@@ -86,9 +78,9 @@ macro_rules! TrivialTypeTraversalImpls {
                 }
             }
 
-            impl<$tcx> $crate::ty::visit::TypeVisitable<$crate::ty::TyCtxt<$tcx>> for $ty {
+            impl<'tcx> $crate::ty::visit::TypeVisitable<$crate::ty::TyCtxt<'tcx>> for $ty {
                 #[inline]
-                fn visit_with<F: $crate::ty::visit::TypeVisitor<$crate::ty::TyCtxt<$tcx>>>(
+                fn visit_with<F: $crate::ty::visit::TypeVisitor<$crate::ty::TyCtxt<'tcx>>>(
                     &self,
                     _: &mut F)
                     -> ::std::ops::ControlFlow<F::BreakTy>
@@ -98,14 +90,6 @@ macro_rules! TrivialTypeTraversalImpls {
             }
         )+
     };
-
-    ($($ty:ty,)+) => {
-        TrivialTypeTraversalImpls! {
-            for<'tcx> {
-                $($ty,)+
-            }
-        }
-    };
 }
 
 #[macro_export]
diff --git a/compiler/rustc_middle/src/mir/mod.rs b/compiler/rustc_middle/src/mir/mod.rs
index 2ea8602af12..f985aae9a22 100644
--- a/compiler/rustc_middle/src/mir/mod.rs
+++ b/compiler/rustc_middle/src/mir/mod.rs
@@ -714,9 +714,7 @@ pub enum BindingForm<'tcx> {
 }
 
 TrivialTypeTraversalAndLiftImpls! {
-    for<'tcx> {
-        BindingForm<'tcx>,
-    }
+    BindingForm<'tcx>,
 }
 
 mod binding_form_impl {
diff --git a/compiler/rustc_middle/src/mir/type_foldable.rs b/compiler/rustc_middle/src/mir/type_foldable.rs
index 9881583214e..ace856b9f95 100644
--- a/compiler/rustc_middle/src/mir/type_foldable.rs
+++ b/compiler/rustc_middle/src/mir/type_foldable.rs
@@ -25,9 +25,7 @@ TrivialTypeTraversalAndLiftImpls! {
 }
 
 TrivialTypeTraversalImpls! {
-    for <'tcx> {
-        ConstValue<'tcx>,
-    }
+    ConstValue<'tcx>,
 }
 
 impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for &'tcx [InlineAsmTemplatePiece] {
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index 63f7cc2ee73..e5356581e6e 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -1329,9 +1329,12 @@ nop_list_lift! {bound_variable_kinds; ty::BoundVariableKind => ty::BoundVariable
 // This is the impl for `&'a InternalSubsts<'a>`.
 nop_list_lift! {substs; GenericArg<'a> => GenericArg<'tcx>}
 
-CloneLiftImpls! { for<'tcx> {
-    Constness, traits::WellFormedLoc, ImplPolarity, crate::mir::ReturnConstraint,
-} }
+CloneLiftImpls! {
+    Constness,
+    traits::WellFormedLoc,
+    ImplPolarity,
+    crate::mir::ReturnConstraint,
+}
 
 macro_rules! sty_debug_print {
     ($fmt: expr, $ctxt: expr, $($variant: ident),*) => {{
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
index bc202b027bd..5501763d66f 100644
--- a/compiler/rustc_middle/src/ty/mod.rs
+++ b/compiler/rustc_middle/src/ty/mod.rs
@@ -1963,6 +1963,16 @@ impl VariantDef {
     pub fn ctor_def_id(&self) -> Option<DefId> {
         self.ctor.map(|(_, def_id)| def_id)
     }
+
+    /// Returns the one field in this variant.
+    ///
+    /// `panic!`s if there are no fields or multiple fields.
+    #[inline]
+    pub fn single_field(&self) -> &FieldDef {
+        assert!(self.fields.len() == 1);
+
+        &self.fields[FieldIdx::from_u32(0)]
+    }
 }
 
 impl PartialEq for VariantDef {
diff --git a/compiler/rustc_middle/src/ty/structural_impls.rs b/compiler/rustc_middle/src/ty/structural_impls.rs
index 619fcea8b7d..7706fdddeb8 100644
--- a/compiler/rustc_middle/src/ty/structural_impls.rs
+++ b/compiler/rustc_middle/src/ty/structural_impls.rs
@@ -276,9 +276,7 @@ TrivialTypeTraversalAndLiftImpls! {
 }
 
 TrivialTypeTraversalAndLiftImpls! {
-    for<'tcx> {
-        ty::ValTree<'tcx>,
-    }
+    ty::ValTree<'tcx>,
 }
 
 ///////////////////////////////////////////////////////////////////////////