Auto merge of rust-lang#137855 - matthiaskrgr:rollup-uh7f3fi, r=matth…

…iaskrgr

Rollup of 10 pull requests

Successful merges:

 - rust-lang#137804 (rename BackendRepr::Vector → SimdVector)
 - rust-lang#137807 (Fully qualify `Result` in generated doctest code)
 - rust-lang#137809 (Use correct error message casing for `io::const_error`s)
 - rust-lang#137818 (tests: adapt for LLVM 21 changes)
 - rust-lang#137822 (Update query normalizer docs to not position it as the greatest pioneer in the space of normalization)
 - rust-lang#137824 (Tweak invalid RTN errors)
 - rust-lang#137828 (Fix inaccurate `std::intrinsics::simd` documentation)
 - rust-lang#137830 (Fix link failure on AVR (incompatible ISA error))
 - rust-lang#137837 (Update `const_conditions` and `explicit_implied_const_bounds` docs)
 - rust-lang#137840 (triagebot: only ping me for constck)

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

compiler/rustc_abi/src/callconv.rs

@@ -74,7 +74,7 @@ impl<'a, Ty> TyAndLayout<'a, Ty> {
                 Ok(HomogeneousAggregate::Homogeneous(Reg { kind, size: self.size }))
             }
 
-            BackendRepr::Vector { .. } => {
+            BackendRepr::SimdVector { .. } => {
                 assert!(!self.is_zst());
                 Ok(HomogeneousAggregate::Homogeneous(Reg {
                     kind: RegKind::Vector,

compiler/rustc_abi/src/layout.rs

@@ -386,13 +386,15 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                     BackendRepr::Memory { sized: true }
                 }
                 // Vectors require at least element alignment, else disable the opt
-                BackendRepr::Vector { element, count: _ } if element.align(dl).abi > align.abi => {
+                BackendRepr::SimdVector { element, count: _ }
+                    if element.align(dl).abi > align.abi =>
+                {
                     BackendRepr::Memory { sized: true }
                 }
                 // the alignment tests passed and we can use this
                 BackendRepr::Scalar(..)
                 | BackendRepr::ScalarPair(..)
-                | BackendRepr::Vector { .. }
+                | BackendRepr::SimdVector { .. }
                 | BackendRepr::Memory { .. } => repr,
             },
         };
@@ -464,7 +466,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                     hide_niches(a);
                     hide_niches(b);
                 }
-                BackendRepr::Vector { element, count: _ } => hide_niches(element),
+                BackendRepr::SimdVector { element, count: _ } => hide_niches(element),
                 BackendRepr::Memory { sized: _ } => {}
             }
             st.largest_niche = None;
@@ -1314,7 +1316,9 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                         match field.backend_repr {
                             // For plain scalars, or vectors of them, we can't unpack
                             // newtypes for `#[repr(C)]`, as that affects C ABIs.
-                            BackendRepr::Scalar(_) | BackendRepr::Vector { .. } if optimize_abi => {
+                            BackendRepr::Scalar(_) | BackendRepr::SimdVector { .. }
+                                if optimize_abi =>
+                            {
                                 abi = field.backend_repr;
                             }
                             // But scalar pairs are Rust-specific and get

compiler/rustc_abi/src/layout/ty.rs

@@ -219,7 +219,7 @@ impl<'a, Ty> TyAndLayout<'a, Ty> {
         C: HasDataLayout,
     {
         match self.backend_repr {
-            BackendRepr::Vector { .. } => self.size == expected_size,
+            BackendRepr::SimdVector { .. } => self.size == expected_size,
             BackendRepr::Memory { .. } => {
                 if self.fields.count() == 1 && self.fields.offset(0).bytes() == 0 {
                     self.field(cx, 0).is_single_vector_element(cx, expected_size)

compiler/rustc_abi/src/lib.rs

@@ -1410,7 +1410,7 @@ impl AddressSpace {
 pub enum BackendRepr {
     Scalar(Scalar),
     ScalarPair(Scalar, Scalar),
-    Vector {
+    SimdVector {
         element: Scalar,
         count: u64,
     },
@@ -1426,9 +1426,9 @@ impl BackendRepr {
     #[inline]
     pub fn is_unsized(&self) -> bool {
         match *self {
-            BackendRepr::Scalar(_) | BackendRepr::ScalarPair(..) | BackendRepr::Vector { .. } => {
-                false
-            }
+            BackendRepr::Scalar(_)
+            | BackendRepr::ScalarPair(..)
+            | BackendRepr::SimdVector { .. } => false,
             BackendRepr::Memory { sized } => !sized,
         }
     }
@@ -1467,7 +1467,7 @@ impl BackendRepr {
             BackendRepr::Scalar(s) => Some(s.align(cx).abi),
             BackendRepr::ScalarPair(s1, s2) => Some(s1.align(cx).max(s2.align(cx)).abi),
             // The align of a Vector can vary in surprising ways
-            BackendRepr::Vector { .. } | BackendRepr::Memory { .. } => None,
+            BackendRepr::SimdVector { .. } | BackendRepr::Memory { .. } => None,
         }
     }
 
@@ -1489,7 +1489,7 @@ impl BackendRepr {
                 Some(size)
             }
             // The size of a Vector can vary in surprising ways
-            BackendRepr::Vector { .. } | BackendRepr::Memory { .. } => None,
+            BackendRepr::SimdVector { .. } | BackendRepr::Memory { .. } => None,
         }
     }
 
@@ -1500,8 +1500,8 @@ impl BackendRepr {
             BackendRepr::ScalarPair(s1, s2) => {
                 BackendRepr::ScalarPair(s1.to_union(), s2.to_union())
             }
-            BackendRepr::Vector { element, count } => {
-                BackendRepr::Vector { element: element.to_union(), count }
+            BackendRepr::SimdVector { element, count } => {
+                BackendRepr::SimdVector { element: element.to_union(), count }
             }
             BackendRepr::Memory { .. } => BackendRepr::Memory { sized: true },
         }
@@ -1513,8 +1513,8 @@ impl BackendRepr {
             // We do *not* ignore the sign since it matters for some ABIs (e.g. s390x).
             (BackendRepr::Scalar(l), BackendRepr::Scalar(r)) => l.primitive() == r.primitive(),
             (
-                BackendRepr::Vector { element: element_l, count: count_l },
-                BackendRepr::Vector { element: element_r, count: count_r },
+                BackendRepr::SimdVector { element: element_l, count: count_l },
+                BackendRepr::SimdVector { element: element_r, count: count_r },
             ) => element_l.primitive() == element_r.primitive() && count_l == count_r,
             (BackendRepr::ScalarPair(l1, l2), BackendRepr::ScalarPair(r1, r2)) => {
                 l1.primitive() == r1.primitive() && l2.primitive() == r2.primitive()
@@ -1735,7 +1735,7 @@ impl<FieldIdx: Idx, VariantIdx: Idx> LayoutData<FieldIdx, VariantIdx> {
     /// Returns `true` if this is an aggregate type (including a ScalarPair!)
     pub fn is_aggregate(&self) -> bool {
         match self.backend_repr {
-            BackendRepr::Scalar(_) | BackendRepr::Vector { .. } => false,
+            BackendRepr::Scalar(_) | BackendRepr::SimdVector { .. } => false,
             BackendRepr::ScalarPair(..) | BackendRepr::Memory { .. } => true,
         }
     }
@@ -1877,9 +1877,9 @@ impl<FieldIdx: Idx, VariantIdx: Idx> LayoutData<FieldIdx, VariantIdx> {
     /// non-trivial alignment constraints. You probably want to use `is_1zst` instead.
     pub fn is_zst(&self) -> bool {
         match self.backend_repr {
-            BackendRepr::Scalar(_) | BackendRepr::ScalarPair(..) | BackendRepr::Vector { .. } => {
-                false
-            }
+            BackendRepr::Scalar(_)
+            | BackendRepr::ScalarPair(..)
+            | BackendRepr::SimdVector { .. } => false,
             BackendRepr::Memory { sized } => sized && self.size.bytes() == 0,
         }
     }

compiler/rustc_ast_lowering/messages.ftl

@@ -37,11 +37,11 @@ ast_lowering_bad_return_type_notation_inputs =
     .suggestion = remove the input types
 
 ast_lowering_bad_return_type_notation_needs_dots = return type notation arguments must be elided with `..`
-    .suggestion = add `..`
+    .suggestion = use the correct syntax by adding `..` to the arguments
 
 ast_lowering_bad_return_type_notation_output =
     return type not allowed with return type notation
-    .suggestion = remove the return type
+ast_lowering_bad_return_type_notation_output_suggestion = use the right argument notation and remove the return type
 
 ast_lowering_bad_return_type_notation_position = return type notation not allowed in this position yet
 

compiler/rustc_ast_lowering/src/errors.rs

@@ -373,24 +373,39 @@ pub(crate) struct InclusiveRangeWithNoEnd {
     pub span: Span,
 }
 
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(
+    ast_lowering_bad_return_type_notation_output_suggestion,
+    applicability = "machine-applicable",
+    style = "verbose"
+)]
+/// Given `T: Tr<m() -> Ret>` or `T: Tr<m(Ty) -> Ret>`, suggest `T: Tr<m(..)>`.
+pub(crate) struct RTNSuggestion {
+    #[suggestion_part(code = "")]
+    pub output: Span,
+    #[suggestion_part(code = "(..)")]
+    pub input: Span,
+}
+
 #[derive(Diagnostic)]
 pub(crate) enum BadReturnTypeNotation {
     #[diag(ast_lowering_bad_return_type_notation_inputs)]
     Inputs {
         #[primary_span]
-        #[suggestion(code = "()", applicability = "maybe-incorrect")]
+        #[suggestion(code = "(..)", applicability = "machine-applicable", style = "verbose")]
         span: Span,
     },
     #[diag(ast_lowering_bad_return_type_notation_output)]
     Output {
         #[primary_span]
-        #[suggestion(code = "", applicability = "maybe-incorrect")]
         span: Span,
+        #[subdiagnostic]
+        suggestion: RTNSuggestion,
     },
     #[diag(ast_lowering_bad_return_type_notation_needs_dots)]
     NeedsDots {
         #[primary_span]
-        #[suggestion(code = "(..)", applicability = "maybe-incorrect")]
+        #[suggestion(code = "(..)", applicability = "machine-applicable", style = "verbose")]
         span: Span,
     },
     #[diag(ast_lowering_bad_return_type_notation_position)]

compiler/rustc_ast_lowering/src/lib.rs

@@ -926,19 +926,27 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                     if let Some(first_char) = constraint.ident.as_str().chars().next()
                         && first_char.is_ascii_lowercase()
                     {
-                        let mut err = if !data.inputs.is_empty() {
-                            self.dcx().create_err(errors::BadReturnTypeNotation::Inputs {
-                                span: data.inputs_span,
-                            })
-                        } else if let FnRetTy::Ty(ty) = &data.output {
-                            self.dcx().create_err(errors::BadReturnTypeNotation::Output {
-                                span: data.inputs_span.shrink_to_hi().to(ty.span),
-                            })
-                        } else {
-                            self.dcx().create_err(errors::BadReturnTypeNotation::NeedsDots {
-                                span: data.inputs_span,
-                            })
+                        tracing::info!(?data, ?data.inputs);
+                        let err = match (&data.inputs[..], &data.output) {
+                            ([_, ..], FnRetTy::Default(_)) => {
+                                errors::BadReturnTypeNotation::Inputs { span: data.inputs_span }
+                            }
+                            ([], FnRetTy::Default(_)) => {
+                                errors::BadReturnTypeNotation::NeedsDots { span: data.inputs_span }
+                            }
+                            // The case `T: Trait<method(..) -> Ret>` is handled in the parser.
+                            (_, FnRetTy::Ty(ty)) => {
+                                let span = data.inputs_span.shrink_to_hi().to(ty.span);
+                                errors::BadReturnTypeNotation::Output {
+                                    span,
+                                    suggestion: errors::RTNSuggestion {
+                                        output: span,
+                                        input: data.inputs_span,
+                                    },
+                                }
+                            }
                         };
+                        let mut err = self.dcx().create_err(err);
                         if !self.tcx.features().return_type_notation()
                             && self.tcx.sess.is_nightly_build()
                         {

compiler/rustc_ast_lowering/src/path.rs

@@ -13,7 +13,7 @@ use tracing::{debug, instrument};
 
 use super::errors::{
     AsyncBoundNotOnTrait, AsyncBoundOnlyForFnTraits, BadReturnTypeNotation,
-    GenericTypeWithParentheses, UseAngleBrackets,
+    GenericTypeWithParentheses, RTNSuggestion, UseAngleBrackets,
 };
 use super::{
     AllowReturnTypeNotation, GenericArgsCtor, GenericArgsMode, ImplTraitContext, ImplTraitPosition,
@@ -268,19 +268,27 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 }
                 GenericArgs::Parenthesized(data) => match generic_args_mode {
                     GenericArgsMode::ReturnTypeNotation => {
-                        let mut err = if !data.inputs.is_empty() {
-                            self.dcx().create_err(BadReturnTypeNotation::Inputs {
-                                span: data.inputs_span,
-                            })
-                        } else if let FnRetTy::Ty(ty) = &data.output {
-                            self.dcx().create_err(BadReturnTypeNotation::Output {
-                                span: data.inputs_span.shrink_to_hi().to(ty.span),
-                            })
-                        } else {
-                            self.dcx().create_err(BadReturnTypeNotation::NeedsDots {
-                                span: data.inputs_span,
-                            })
+                        tracing::info!(?data, ?data.inputs);
+                        let err = match (&data.inputs[..], &data.output) {
+                            ([_, ..], FnRetTy::Default(_)) => {
+                                BadReturnTypeNotation::Inputs { span: data.inputs_span }
+                            }
+                            ([], FnRetTy::Default(_)) => {
+                                BadReturnTypeNotation::NeedsDots { span: data.inputs_span }
+                            }
+                            // The case `T: Trait<method(..) -> Ret>` is handled in the parser.
+                            (_, FnRetTy::Ty(ty)) => {
+                                let span = data.inputs_span.shrink_to_hi().to(ty.span);
+                                BadReturnTypeNotation::Output {
+                                    span,
+                                    suggestion: RTNSuggestion {
+                                        output: span,
+                                        input: data.inputs_span,
+                                    },
+                                }
+                            }
                         };
+                        let mut err = self.dcx().create_err(err);
                         if !self.tcx.features().return_type_notation()
                             && self.tcx.sess.is_nightly_build()
                         {

compiler/rustc_codegen_cranelift/src/abi/pass_mode.rs

@@ -84,7 +84,7 @@ impl<'tcx> ArgAbiExt<'tcx> for ArgAbi<'tcx, Ty<'tcx>> {
                     AbiParam::new(scalar_to_clif_type(tcx, scalar)),
                     attrs
                 )],
-                BackendRepr::Vector { .. } => {
+                BackendRepr::SimdVector { .. } => {
                     let vector_ty = crate::intrinsics::clif_vector_type(tcx, self.layout);
                     smallvec![AbiParam::new(vector_ty)]
                 }
@@ -135,7 +135,7 @@ impl<'tcx> ArgAbiExt<'tcx> for ArgAbi<'tcx, Ty<'tcx>> {
                 BackendRepr::Scalar(scalar) => {
                     (None, vec![AbiParam::new(scalar_to_clif_type(tcx, scalar))])
                 }
-                BackendRepr::Vector { .. } => {
+                BackendRepr::SimdVector { .. } => {
                     let vector_ty = crate::intrinsics::clif_vector_type(tcx, self.layout);
                     (None, vec![AbiParam::new(vector_ty)])
                 }

compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs

@@ -53,7 +53,7 @@ fn report_atomic_type_validation_error<'tcx>(
 
 pub(crate) fn clif_vector_type<'tcx>(tcx: TyCtxt<'tcx>, layout: TyAndLayout<'tcx>) -> Type {
     let (element, count) = match layout.backend_repr {
-        BackendRepr::Vector { element, count } => (element, count),
+        BackendRepr::SimdVector { element, count } => (element, count),
         _ => unreachable!(),
     };
 

compiler/rustc_codegen_cranelift/src/value_and_place.rs

@@ -173,9 +173,11 @@ impl<'tcx> CValue<'tcx> {
             CValueInner::ByRef(ptr, None) => {
                 let clif_ty = match layout.backend_repr {
                     BackendRepr::Scalar(scalar) => scalar_to_clif_type(fx.tcx, scalar),
-                    BackendRepr::Vector { element, count } => scalar_to_clif_type(fx.tcx, element)
-                        .by(u32::try_from(count).unwrap())
-                        .unwrap(),
+                    BackendRepr::SimdVector { element, count } => {
+                        scalar_to_clif_type(fx.tcx, element)
+                            .by(u32::try_from(count).unwrap())
+                            .unwrap()
+                    }
                     _ => unreachable!("{:?}", layout.ty),
                 };
                 let mut flags = MemFlags::new();

compiler/rustc_codegen_gcc/src/intrinsic/mod.rs

@@ -312,7 +312,7 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
                 let layout = self.layout_of(tp_ty).layout;
                 let _use_integer_compare = match layout.backend_repr() {
                     Scalar(_) | ScalarPair(_, _) => true,
-                    Vector { .. } => false,
+                    SimdVector { .. } => false,
                     Memory { .. } => {
                         // For rusty ABIs, small aggregates are actually passed
                         // as `RegKind::Integer` (see `FnAbi::adjust_for_abi`),

compiler/rustc_codegen_gcc/src/type_of.rs

@@ -63,7 +63,7 @@ fn uncached_gcc_type<'gcc, 'tcx>(
 ) -> Type<'gcc> {
     match layout.backend_repr {
         BackendRepr::Scalar(_) => bug!("handled elsewhere"),
-        BackendRepr::Vector { ref element, count } => {
+        BackendRepr::SimdVector { ref element, count } => {
             let element = layout.scalar_gcc_type_at(cx, element, Size::ZERO);
             let element =
                 // NOTE: gcc doesn't allow pointer types in vectors.
@@ -178,17 +178,17 @@ pub trait LayoutGccExt<'tcx> {
 impl<'tcx> LayoutGccExt<'tcx> for TyAndLayout<'tcx> {
     fn is_gcc_immediate(&self) -> bool {
         match self.backend_repr {
-            BackendRepr::Scalar(_) | BackendRepr::Vector { .. } => true,
+            BackendRepr::Scalar(_) | BackendRepr::SimdVector { .. } => true,
             BackendRepr::ScalarPair(..) | BackendRepr::Memory { .. } => false,
         }
     }
 
     fn is_gcc_scalar_pair(&self) -> bool {
         match self.backend_repr {
             BackendRepr::ScalarPair(..) => true,
-            BackendRepr::Scalar(_) | BackendRepr::Vector { .. } | BackendRepr::Memory { .. } => {
-                false
-            }
+            BackendRepr::Scalar(_)
+            | BackendRepr::SimdVector { .. }
+            | BackendRepr::Memory { .. } => false,
         }
     }