diff options
101 files changed, 1837 insertions, 801 deletions
diff --git a/RELEASES.md b/RELEASES.md index e0175db7ec8..1dd3fbea613 100644 --- a/RELEASES.md +++ b/RELEASES.md @@ -16,8 +16,7 @@ Version 1.84.1 (2025-01-30) Version 1.84.0 (2025-01-09) ========================== -<a id=" -Language"></a> +<a id="1.84.0-Language"></a> Language -------- diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs index ad942e9b494..b6f331d316c 100644 --- a/compiler/rustc_ast/src/ast.rs +++ b/compiler/rustc_ast/src/ast.rs @@ -1657,7 +1657,7 @@ impl GenBlockKind { } /// Whether we're unwrapping or wrapping an unsafe binder -#[derive(Copy, Clone, Debug, PartialEq, Eq)] +#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)] #[derive(Encodable, Decodable, HashStable_Generic)] pub enum UnsafeBinderCastKind { // e.g. `&i32` -> `unsafe<'a> &'a i32` diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs index 0118b72962d..f200f77203c 100644 --- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs @@ -3915,7 +3915,8 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { ProjectionElem::ConstantIndex { .. } | ProjectionElem::Subslice { .. } | ProjectionElem::Subtype(_) - | ProjectionElem::Index(_) => kind, + | ProjectionElem::Index(_) + | ProjectionElem::UnwrapUnsafeBinder(_) => kind, }, place_ty.projection_ty(tcx, elem), ) diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs index 5fe8eef3460..92c0536ea98 100644 --- a/compiler/rustc_borrowck/src/diagnostics/mod.rs +++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs @@ -370,6 +370,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { ProjectionElem::Downcast(..) => (), ProjectionElem::OpaqueCast(..) => (), ProjectionElem::Subtype(..) => (), + ProjectionElem::UnwrapUnsafeBinder(_) => (), ProjectionElem::Field(field, _ty) => { // FIXME(project-rfc_2229#36): print capture precisely here. if let Some(field) = self.is_upvar_field_projection(PlaceRef { @@ -450,9 +451,9 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { PlaceRef { local, projection: proj_base }.ty(self.body, self.infcx.tcx) } ProjectionElem::Downcast(..) => place.ty(self.body, self.infcx.tcx), - ProjectionElem::Subtype(ty) | ProjectionElem::OpaqueCast(ty) => { - PlaceTy::from_ty(*ty) - } + ProjectionElem::Subtype(ty) + | ProjectionElem::OpaqueCast(ty) + | ProjectionElem::UnwrapUnsafeBinder(ty) => PlaceTy::from_ty(*ty), ProjectionElem::Field(_, field_type) => PlaceTy::from_ty(*field_type), }, }; diff --git a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs index e841a5e4c94..706dd7135f7 100644 --- a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs @@ -167,7 +167,8 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { | ProjectionElem::ConstantIndex { .. } | ProjectionElem::OpaqueCast { .. } | ProjectionElem::Subslice { .. } - | ProjectionElem::Downcast(..), + | ProjectionElem::Downcast(..) + | ProjectionElem::UnwrapUnsafeBinder(_), ], } => bug!("Unexpected immutable place."), } diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs index decfab502bb..077d8f49df8 100644 --- a/compiler/rustc_borrowck/src/lib.rs +++ b/compiler/rustc_borrowck/src/lib.rs @@ -1398,6 +1398,10 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, '_, 'tcx> { self.consume_operand(location, (operand, span), state); } } + + Rvalue::WrapUnsafeBinder(op, _) => { + self.consume_operand(location, (op, span), state); + } } } @@ -1770,7 +1774,8 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, '_, 'tcx> { // So it's safe to skip these. ProjectionElem::OpaqueCast(_) | ProjectionElem::Subtype(_) - | ProjectionElem::Downcast(_, _) => (), + | ProjectionElem::Downcast(_, _) + | ProjectionElem::UnwrapUnsafeBinder(_) => (), } place_ty = place_ty.projection_ty(tcx, elem); @@ -2004,6 +2009,10 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, '_, 'tcx> { // FIXME: is this true even if P is an adt with a dtor? { } + ProjectionElem::UnwrapUnsafeBinder(_) => { + check_parent_of_field(self, location, place_base, span, state); + } + // assigning to (*P) requires P to be initialized ProjectionElem::Deref => { self.check_if_full_path_is_moved( @@ -2384,7 +2393,8 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, '_, 'tcx> { | ProjectionElem::Subslice { .. } | ProjectionElem::Subtype(..) | ProjectionElem::OpaqueCast { .. } - | ProjectionElem::Downcast(..) => { + | ProjectionElem::Downcast(..) + | ProjectionElem::UnwrapUnsafeBinder(_) => { let upvar_field_projection = self.is_upvar_field_projection(place); if let Some(field) = upvar_field_projection { let upvar = &self.upvars[field.index()]; diff --git a/compiler/rustc_borrowck/src/places_conflict.rs b/compiler/rustc_borrowck/src/places_conflict.rs index 679e111caa9..cf3e82426e8 100644 --- a/compiler/rustc_borrowck/src/places_conflict.rs +++ b/compiler/rustc_borrowck/src/places_conflict.rs @@ -250,7 +250,8 @@ fn place_components_conflict<'tcx>( | (ProjectionElem::Subslice { .. }, _, _) | (ProjectionElem::OpaqueCast { .. }, _, _) | (ProjectionElem::Subtype(_), _, _) - | (ProjectionElem::Downcast { .. }, _, _) => { + | (ProjectionElem::Downcast { .. }, _, _) + | (ProjectionElem::UnwrapUnsafeBinder(_), _, _) => { // Recursive case. This can still be disjoint on a // further iteration if this a shallow access and // there's a deref later on, e.g., a borrow @@ -519,5 +520,9 @@ fn place_projection_conflict<'tcx>( pi1_elem, pi2_elem ), + + (ProjectionElem::UnwrapUnsafeBinder(_), _) => { + todo!() + } } } diff --git a/compiler/rustc_borrowck/src/polonius/legacy/loan_invalidations.rs b/compiler/rustc_borrowck/src/polonius/legacy/loan_invalidations.rs index f79bcf5af55..0d1d8642bca 100644 --- a/compiler/rustc_borrowck/src/polonius/legacy/loan_invalidations.rs +++ b/compiler/rustc_borrowck/src/polonius/legacy/loan_invalidations.rs @@ -325,6 +325,10 @@ impl<'a, 'tcx> LoanInvalidationsGenerator<'a, 'tcx> { self.consume_operand(location, operand); } } + + Rvalue::WrapUnsafeBinder(op, _) => { + self.consume_operand(location, op); + } } } diff --git a/compiler/rustc_borrowck/src/prefixes.rs b/compiler/rustc_borrowck/src/prefixes.rs index fc7e6e58641..83cca38a5c0 100644 --- a/compiler/rustc_borrowck/src/prefixes.rs +++ b/compiler/rustc_borrowck/src/prefixes.rs @@ -66,6 +66,10 @@ impl<'tcx> Iterator for Prefixes<'tcx> { self.next = Some(cursor_base); return Some(cursor); } + ProjectionElem::UnwrapUnsafeBinder(_) => { + self.next = Some(cursor_base); + return Some(cursor); + } ProjectionElem::Downcast(..) | ProjectionElem::Subslice { .. } | ProjectionElem::OpaqueCast { .. } diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs index a2ef5588f48..92492bfdb8d 100644 --- a/compiler/rustc_borrowck/src/type_check/mod.rs +++ b/compiler/rustc_borrowck/src/type_check/mod.rs @@ -302,6 +302,25 @@ impl<'a, 'b, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'tcx> { ) .unwrap(); } + ProjectionElem::UnwrapUnsafeBinder(ty) => { + let ty::UnsafeBinder(binder_ty) = *base_ty.ty.kind() else { + unreachable!(); + }; + let found_ty = self.typeck.infcx.instantiate_binder_with_fresh_vars( + self.body().source_info(location).span, + BoundRegionConversionTime::HigherRankedType, + binder_ty.into(), + ); + self.typeck + .relate_types( + ty, + context.ambient_variance(), + found_ty, + location.to_locations(), + ConstraintCategory::Boring, + ) + .unwrap(); + } ProjectionElem::Subtype(_) => { bug!("ProjectionElem::Subtype shouldn't exist in borrowck") } @@ -2233,6 +2252,27 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> { self.check_operand(right, location); } + Rvalue::WrapUnsafeBinder(op, ty) => { + self.check_operand(op, location); + let operand_ty = op.ty(self.body, self.tcx()); + + let ty::UnsafeBinder(binder_ty) = *ty.kind() else { + unreachable!(); + }; + let expected_ty = self.infcx.instantiate_binder_with_fresh_vars( + self.body().source_info(location).span, + BoundRegionConversionTime::HigherRankedType, + binder_ty.into(), + ); + self.sub_types( + operand_ty, + expected_ty, + location.to_locations(), + ConstraintCategory::Boring, + ) + .unwrap(); + } + Rvalue::RawPtr(..) | Rvalue::ThreadLocalRef(..) | Rvalue::Len(..) @@ -2258,7 +2298,8 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> { | Rvalue::NullaryOp(..) | Rvalue::CopyForDeref(..) | Rvalue::UnaryOp(..) - | Rvalue::Discriminant(..) => None, + | Rvalue::Discriminant(..) + | Rvalue::WrapUnsafeBinder(..) => None, Rvalue::Aggregate(aggregate, _) => match **aggregate { AggregateKind::Adt(_, _, _, user_ty, _) => user_ty, @@ -2450,7 +2491,8 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> { | ProjectionElem::OpaqueCast(..) | ProjectionElem::Index(..) | ProjectionElem::ConstantIndex { .. } - | ProjectionElem::Subslice { .. } => { + | ProjectionElem::Subslice { .. } + | ProjectionElem::UnwrapUnsafeBinder(_) => { // other field access } ProjectionElem::Subtype(_) => { diff --git a/compiler/rustc_codegen_cranelift/src/base.rs b/compiler/rustc_codegen_cranelift/src/base.rs index c7c9c6236d1..7a40d236b92 100644 --- a/compiler/rustc_codegen_cranelift/src/base.rs +++ b/compiler/rustc_codegen_cranelift/src/base.rs @@ -925,6 +925,10 @@ fn codegen_stmt<'tcx>( } crate::discriminant::codegen_set_discriminant(fx, lval, variant_index); } + Rvalue::WrapUnsafeBinder(ref operand, _to_ty) => { + let operand = codegen_operand(fx, operand); + lval.write_cvalue_transmute(fx, operand); + } } } StatementKind::StorageLive(_) @@ -993,7 +997,9 @@ pub(crate) fn codegen_place<'tcx>( cplace = cplace.place_deref(fx); } PlaceElem::OpaqueCast(ty) => bug!("encountered OpaqueCast({ty}) in codegen"), - PlaceElem::Subtype(ty) => cplace = cplace.place_transmute_type(fx, fx.monomorphize(ty)), + PlaceElem::Subtype(ty) | PlaceElem::UnwrapUnsafeBinder(ty) => { + cplace = cplace.place_transmute_type(fx, fx.monomorphize(ty)); + } PlaceElem::Field(field, _ty) => { cplace = cplace.place_field(fx, field); } diff --git a/compiler/rustc_codegen_llvm/src/llvm/enzyme_ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/enzyme_ffi.rs index ae813fe5ebf..92b0ce8ffe1 100644 --- a/compiler/rustc_codegen_llvm/src/llvm/enzyme_ffi.rs +++ b/compiler/rustc_codegen_llvm/src/llvm/enzyme_ffi.rs @@ -4,6 +4,8 @@ use libc::{c_char, c_uint}; use super::ffi::{BasicBlock, Metadata, Module, Type, Value}; use crate::llvm::Bool; + +#[link(name = "llvm-wrapper", kind = "static")] extern "C" { // Enzyme pub fn LLVMRustHasMetadata(I: &Value, KindID: c_uint) -> bool; @@ -12,10 +14,13 @@ extern "C" { pub fn LLVMRustDIGetInstMetadata(I: &Value) -> Option<&Metadata>; pub fn LLVMRustEraseInstFromParent(V: &Value); pub fn LLVMRustGetTerminator<'a>(B: &BasicBlock) -> &'a Value; - pub fn LLVMDumpModule(M: &Module); - pub fn LLVMDumpValue(V: &Value); pub fn LLVMRustVerifyFunction(V: &Value, action: LLVMRustVerifierFailureAction) -> Bool; +} +extern "C" { + // Enzyme + pub fn LLVMDumpModule(M: &Module); + pub fn LLVMDumpValue(V: &Value); pub fn LLVMGetFunctionCallConv(F: &Value) -> c_uint; pub fn LLVMGetReturnType(T: &Type) -> &Type; pub fn LLVMGetParams(Fnc: &Value, parms: *mut &Value); diff --git a/compiler/rustc_codegen_ssa/src/mir/place.rs b/compiler/rustc_codegen_ssa/src/mir/place.rs index c634f864ffb..73a41676802 100644 --- a/compiler/rustc_codegen_ssa/src/mir/place.rs +++ b/compiler/rustc_codegen_ssa/src/mir/place.rs @@ -502,6 +502,9 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { bug!("encountered OpaqueCast({ty}) in codegen") } mir::ProjectionElem::Subtype(ty) => cg_base.project_type(bx, self.monomorphize(ty)), + mir::ProjectionElem::UnwrapUnsafeBinder(ty) => { + cg_base.project_type(bx, self.monomorphize(ty)) + } mir::ProjectionElem::Index(index) => { let index = &mir::Operand::Copy(mir::Place::from(index)); let index = self.codegen_operand(bx, index); diff --git a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs index d7fc5e8e673..85de3238b3e 100644 --- a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs +++ b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs @@ -823,6 +823,12 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { OperandRef { val: OperandValue::Immediate(val), layout: box_layout } } + mir::Rvalue::WrapUnsafeBinder(ref operand, binder_ty) => { + let operand = self.codegen_operand(bx, operand); + let binder_ty = self.monomorphize(binder_ty); + let layout = bx.cx().layout_of(binder_ty); + OperandRef { val: operand.val, layout } + } } } @@ -1123,7 +1129,8 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { mir::Rvalue::Discriminant(..) | mir::Rvalue::NullaryOp(..) | mir::Rvalue::ThreadLocalRef(_) | - mir::Rvalue::Use(..) => // (*) + mir::Rvalue::Use(..) | + mir::Rvalue::WrapUnsafeBinder(..) => // (*) true, // Arrays are always aggregates, so it's not worth checking anything here. // (If it's really `[(); N]` or `[T; 0]` and we use the place path, fine.) diff --git a/compiler/rustc_const_eval/src/check_consts/check.rs b/compiler/rustc_const_eval/src/check_consts/check.rs index 4834fd3d34c..e8052a3c83a 100644 --- a/compiler/rustc_const_eval/src/check_consts/check.rs +++ b/compiler/rustc_const_eval/src/check_consts/check.rs @@ -728,6 +728,10 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { ); } } + + Rvalue::WrapUnsafeBinder(..) => { + // Unsafe binders are always trivial to create. + } } } diff --git a/compiler/rustc_const_eval/src/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/check_consts/qualifs.rs index 5d368b600a0..9c99782d223 100644 --- a/compiler/rustc_const_eval/src/check_consts/qualifs.rs +++ b/compiler/rustc_const_eval/src/check_consts/qualifs.rs @@ -258,6 +258,8 @@ where in_place::<Q, _>(cx, in_local, place.as_ref()) } + Rvalue::WrapUnsafeBinder(op, _) => in_operand::<Q, _>(cx, in_local, op), + Rvalue::Aggregate(kind, operands) => { // Return early if we know that the struct or enum being constructed is always // qualified. @@ -297,7 +299,8 @@ where | ProjectionElem::ConstantIndex { .. } | ProjectionElem::Subslice { .. } | ProjectionElem::Downcast(_, _) - | ProjectionElem::Index(_) => {} + | ProjectionElem::Index(_) + | ProjectionElem::UnwrapUnsafeBinder(_) => {} } let base_ty = place_base.ty(cx.body, cx.tcx); diff --git a/compiler/rustc_const_eval/src/check_consts/resolver.rs b/compiler/rustc_const_eval/src/check_consts/resolver.rs index 79df63a9e84..8cee282311f 100644 --- a/compiler/rustc_const_eval/src/check_consts/resolver.rs +++ b/compiler/rustc_const_eval/src/check_consts/resolver.rs @@ -202,7 +202,8 @@ where | mir::Rvalue::NullaryOp(..) | mir::Rvalue::UnaryOp(..) | mir::Rvalue::Discriminant(..) - | mir::Rvalue::Aggregate(..) => {} + | mir::Rvalue::Aggregate(..) + | mir::Rvalue::WrapUnsafeBinder(..) => {} } } diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs index 0664a882c1d..9f5f2533e08 100644 --- a/compiler/rustc_const_eval/src/interpret/intrinsics.rs +++ b/compiler/rustc_const_eval/src/interpret/intrinsics.rs @@ -747,7 +747,13 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { { let a: F = self.read_scalar(&args[0])?.to_float()?; let b: F = self.read_scalar(&args[1])?.to_float()?; - let res = self.adjust_nan(a.min(b), &[a, b]); + let res = if a == b { + // They are definitely not NaN (those are never equal), but they could be `+0` and `-0`. + // Let the machine decide which one to return. + M::equal_float_min_max(self, a, b) + } else { + self.adjust_nan(a.min(b), &[a, b]) + }; self.write_scalar(res, dest)?; interp_ok(()) } @@ -762,7 +768,13 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { { let a: F = self.read_scalar(&args[0])?.to_float()?; let b: F = self.read_scalar(&args[1])?.to_float()?; - let res = self.adjust_nan(a.max(b), &[a, b]); + let res = if a == b { + // They are definitely not NaN (those are never equal), but they could be `+0` and `-0`. + // Let the machine decide which one to return. + M::equal_float_min_max(self, a, b) + } else { + self.adjust_nan(a.max(b), &[a, b]) + }; self.write_scalar(res, dest)?; interp_ok(()) } diff --git a/compiler/rustc_const_eval/src/interpret/machine.rs b/compiler/rustc_const_eval/src/interpret/machine.rs index 36e5a2ff750..8f6b15b8df0 100644 --- a/compiler/rustc_const_eval/src/interpret/machine.rs +++ b/compiler/rustc_const_eval/src/interpret/machine.rs @@ -278,6 +278,12 @@ pub trait Machine<'tcx>: Sized { F2::NAN } + /// Determines the result of `min`/`max` on floats when the arguments are equal. + fn equal_float_min_max<F: Float>(_ecx: &InterpCx<'tcx, Self>, a: F, _b: F) -> F { + // By default, we pick the left argument. + a + } + /// Called before a basic block terminator is executed. #[inline] fn before_terminator(_ecx: &mut InterpCx<'tcx, Self>) -> InterpResult<'tcx> { diff --git a/compiler/rustc_const_eval/src/interpret/projection.rs b/compiler/rustc_const_eval/src/interpret/projection.rs index 996142d7b03..8ecb3e13d5c 100644 --- a/compiler/rustc_const_eval/src/interpret/projection.rs +++ b/compiler/rustc_const_eval/src/interpret/projection.rs @@ -381,6 +381,7 @@ where OpaqueCast(ty) => { span_bug!(self.cur_span(), "OpaqueCast({ty}) encountered after borrowck") } + UnwrapUnsafeBinder(target) => base.transmute(self.layout_of(target)?, self)?, // We don't want anything happening here, this is here as a dummy. Subtype(_) => base.transmute(base.layout(), self)?, Field(field, _) => self.project_field(base, field.index())?, diff --git a/compiler/rustc_const_eval/src/interpret/step.rs b/compiler/rustc_const_eval/src/interpret/step.rs index d9c0ff5acd1..abe73c43d8a 100644 --- a/compiler/rustc_const_eval/src/interpret/step.rs +++ b/compiler/rustc_const_eval/src/interpret/step.rs @@ -277,6 +277,13 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { let discr = self.discriminant_for_variant(op.layout.ty, variant)?; self.write_immediate(*discr, &dest)?; } + + WrapUnsafeBinder(ref op, _ty) => { + // Constructing an unsafe binder acts like a transmute + // since the operand's layout does not change. + let op = self.eval_operand(op, None)?; + self.copy_op_allow_transmute(&op, &dest)?; + } } trace!("{:?}", self.dump_place(&dest)); diff --git a/compiler/rustc_hir_typeck/src/expr.rs b/compiler/rustc_hir_typeck/src/expr.rs index f79667e59ba..4abc6da4e65 100644 --- a/compiler/rustc_hir_typeck/src/expr.rs +++ b/compiler/rustc_hir_typeck/src/expr.rs @@ -1658,8 +1658,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { hir_ty: Option<&'tcx hir::Ty<'tcx>>, expected: Expectation<'tcx>, ) -> Ty<'tcx> { - self.dcx().span_err(inner_expr.span, "unsafe binder casts are not fully implemented"); - match kind { hir::UnsafeBinderCastKind::Wrap => { let ascribed_ty = diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs index e84ae65f903..9277d71234f 100644 --- a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs +++ b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs @@ -253,6 +253,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { return; } + let mut expr_ty = self.typeck_results.borrow().expr_ty_adjusted(expr); + for a in &adj { match a.kind { Adjust::NeverToAny => { @@ -266,7 +268,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { None, expr.span, overloaded_deref.method_call(self.tcx), - self.tcx.mk_args(&[a.target.into()]), + self.tcx.mk_args(&[expr_ty.into()]), ); } Adjust::Deref(None) => { @@ -283,6 +285,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // No effects to enforce here. } } + + expr_ty = a.target; } let autoborrow_mut = adj.iter().any(|adj| { diff --git a/compiler/rustc_middle/src/mir/pretty.rs b/compiler/rustc_middle/src/mir/pretty.rs index a318bacb866..09d7e60e199 100644 --- a/compiler/rustc_middle/src/mir/pretty.rs +++ b/compiler/rustc_middle/src/mir/pretty.rs @@ -1248,6 +1248,10 @@ impl<'tcx> Debug for Rvalue<'tcx> { ShallowInitBox(ref place, ref ty) => { with_no_trimmed_paths!(write!(fmt, "ShallowInitBox({place:?}, {ty})")) } + + WrapUnsafeBinder(ref op, ty) => { + with_no_trimmed_paths!(write!(fmt, "wrap_binder!({op:?}; {ty})")) + } } } } @@ -1308,6 +1312,9 @@ fn pre_fmt_projection(projection: &[PlaceElem<'_>], fmt: &mut Formatter<'_>) -> ProjectionElem::Index(_) | ProjectionElem::ConstantIndex { .. } | ProjectionElem::Subslice { .. } => {} + ProjectionElem::UnwrapUnsafeBinder(_) => { + write!(fmt, "unwrap_binder!(")?; + } } } @@ -1356,6 +1363,9 @@ fn post_fmt_projection(projection: &[PlaceElem<'_>], fmt: &mut Formatter<'_>) -> ProjectionElem::Subslice { from, to, from_end: false } => { write!(fmt, "[{from:?}..{to:?}]")?; } + ProjectionElem::UnwrapUnsafeBinder(ty) => { + write!(fmt, "; {ty})")?; + } } } diff --git a/compiler/rustc_middle/src/mir/statement.rs b/compiler/rustc_middle/src/mir/statement.rs index 609d5647d04..d345c99f902 100644 --- a/compiler/rustc_middle/src/mir/statement.rs +++ b/compiler/rustc_middle/src/mir/statement.rs @@ -62,7 +62,8 @@ impl<V, T> ProjectionElem<V, T> { | Self::Subtype(_) | Self::ConstantIndex { .. } | Self::Subslice { .. } - | Self::Downcast(_, _) => false, + | Self::Downcast(_, _) + | Self::UnwrapUnsafeBinder(..) => false, } } @@ -76,7 +77,8 @@ impl<V, T> ProjectionElem<V, T> { | Self::Subtype(_) | Self::ConstantIndex { .. } | Self::Subslice { .. } - | Self::Downcast(_, _) => true, + | Self::Downcast(_, _) + | Self::UnwrapUnsafeBinder(..) => true, } } @@ -102,6 +104,9 @@ impl<V, T> ProjectionElem<V, T> { | Self::Subtype(_) | Self::OpaqueCast(_) | Self::Subslice { .. } => false, + + // FIXME(unsafe_binders): Figure this out. + Self::UnwrapUnsafeBinder(..) => false, } } } @@ -443,7 +448,8 @@ impl<'tcx> Rvalue<'tcx> { | Rvalue::UnaryOp(_, _) | Rvalue::Discriminant(_) | Rvalue::Aggregate(_, _) - | Rvalue::ShallowInitBox(_, _) => true, + | Rvalue::ShallowInitBox(_, _) + | Rvalue::WrapUnsafeBinder(_, _) => true, } } } diff --git a/compiler/rustc_middle/src/mir/syntax.rs b/compiler/rustc_middle/src/mir/syntax.rs index 90a2f175bc9..2da25f480c6 100644 --- a/compiler/rustc_middle/src/mir/syntax.rs +++ b/compiler/rustc_middle/src/mir/syntax.rs @@ -1276,6 +1276,10 @@ pub enum ProjectionElem<V, T> { /// requiring an intermediate variable. OpaqueCast(T), + /// A transmute from an unsafe binder to the type that it wraps. This is a projection + /// of a place, so it doesn't necessarily constitute a move out of the binder. + UnwrapUnsafeBinder(T), + /// A `Subtype(T)` projection is applied to any `StatementKind::Assign` where /// type of lvalue doesn't match the type of rvalue, the primary goal is making subtyping /// explicit during optimizations and codegen. @@ -1493,6 +1497,9 @@ pub enum Rvalue<'tcx> { /// optimizations and codegen backends that previously had to handle deref operations anywhere /// in a place. CopyForDeref(Place<'tcx>), + + /// Wraps a value in an unsafe binder. + WrapUnsafeBinder(Operand<'tcx>, Ty<'tcx>), } #[derive(Clone, Copy, Debug, PartialEq, Eq, TyEncodable, TyDecodable, Hash, HashStable)] diff --git a/compiler/rustc_middle/src/mir/tcx.rs b/compiler/rustc_middle/src/mir/tcx.rs index 4d11492e94d..49449426fa4 100644 --- a/compiler/rustc_middle/src/mir/tcx.rs +++ b/compiler/rustc_middle/src/mir/tcx.rs @@ -146,6 +146,11 @@ impl<'tcx> PlaceTy<'tcx> { ProjectionElem::Subtype(ty) => { PlaceTy::from_ty(handle_opaque_cast_and_subtype(&self, ty)) } + + // FIXME(unsafe_binders): Rename `handle_opaque_cast_and_subtype` to be more general. + ProjectionElem::UnwrapUnsafeBinder(ty) => { + PlaceTy::from_ty(handle_opaque_cast_and_subtype(&self, ty)) + } }; debug!("projection_ty self: {:?} elem: {:?} yields: {:?}", self, elem, answer); answer @@ -241,6 +246,7 @@ impl<'tcx> Rvalue<'tcx> { }, Rvalue::ShallowInitBox(_, ty) => Ty::new_box(tcx, ty), Rvalue::CopyForDeref(ref place) => place.ty(local_decls, tcx).ty, + Rvalue::WrapUnsafeBinder(_, ty) => ty, } } diff --git a/compiler/rustc_middle/src/mir/type_foldable.rs b/compiler/rustc_middle/src/mir/type_foldable.rs index b59b9e55fe8..9893dd0484c 100644 --- a/compiler/rustc_middle/src/mir/type_foldable.rs +++ b/compiler/rustc_middle/src/mir/type_foldable.rs @@ -1,6 +1,7 @@ //! `TypeFoldable` implementations for MIR types use rustc_ast::InlineAsmTemplatePiece; +use rustc_hir::UnsafeBinderCastKind; use rustc_hir::def_id::LocalDefId; use super::*; @@ -21,6 +22,7 @@ TrivialTypeTraversalImpls! { SwitchTargets, CoroutineKind, CoroutineSavedLocal, + UnsafeBinderCastKind, } TrivialTypeTraversalImpls! { diff --git a/compiler/rustc_middle/src/mir/visit.rs b/compiler/rustc_middle/src/mir/visit.rs index 6319a7e65b9..8d04bbb95bd 100644 --- a/compiler/rustc_middle/src/mir/visit.rs +++ b/compiler/rustc_middle/src/mir/visit.rs @@ -781,6 +781,11 @@ macro_rules! make_mir_visitor { self.visit_operand(operand, location); self.visit_ty($(& $mutability)? *ty, TyContext::Location(location)); } + + Rvalue::WrapUnsafeBinder(op, ty) => { + self.visit_operand(op, location); + self.visit_ty($(& $mutability)? *ty, TyContext::Location(location)); + } } } @@ -1151,6 +1156,11 @@ macro_rules! visit_place_fns { self.visit_ty(&mut new_ty, TyContext::Location(location)); if ty != new_ty { Some(PlaceElem::Subtype(new_ty)) } else { None } } + PlaceElem::UnwrapUnsafeBinder(ty) => { + let mut new_ty = ty; + self.visit_ty(&mut new_ty, TyContext::Location(location)); + if ty != new_ty { Some(PlaceElem::UnwrapUnsafeBinder(new_ty)) } else { None } + } PlaceElem::Deref | PlaceElem::ConstantIndex { .. } | PlaceElem::Subslice { .. } @@ -1219,7 +1229,8 @@ macro_rules! visit_place_fns { match elem { ProjectionElem::OpaqueCast(ty) | ProjectionElem::Subtype(ty) - | ProjectionElem::Field(_, ty) => { + | ProjectionElem::Field(_, ty) + | ProjectionElem::UnwrapUnsafeBinder(ty) => { self.visit_ty(ty, TyContext::Location(location)); } ProjectionElem::Index(local) => { diff --git a/compiler/rustc_middle/src/thir.rs b/compiler/rustc_middle/src/thir.rs index 86014c34b45..d56046136c7 100644 --- a/compiler/rustc_middle/src/thir.rs +++ b/compiler/rustc_middle/src/thir.rs @@ -489,6 +489,19 @@ pub enum ExprKind<'tcx> { user_ty: UserTy<'tcx>, user_ty_span: Span, }, + /// An unsafe binder cast on a place, e.g. `unwrap_binder!(*ptr)`. + PlaceUnwrapUnsafeBinder { + source: ExprId, + }, + /// An unsafe binder cast on a value, e.g. `unwrap_binder!(rvalue())`, + /// which makes a temporary. + ValueUnwrapUnsafeBinder { + source: ExprId, + }, + /// Construct an unsafe binder, e.g. `wrap_binder(&ref)`. + WrapUnsafeBinder { + source: ExprId, + }, /// A closure definition. Closure(Box<ClosureExpr<'tcx>>), /// A literal. diff --git a/compiler/rustc_middle/src/thir/visit.rs b/compiler/rustc_middle/src/thir/visit.rs index 64bac12b266..2aeb13942a3 100644 --- a/compiler/rustc_middle/src/thir/visit.rs +++ b/compiler/rustc_middle/src/thir/visit.rs @@ -136,6 +136,9 @@ pub fn walk_expr<'thir, 'tcx: 'thir, V: Visitor<'thir, 'tcx>>( | ValueTypeAscription { source, user_ty: _, user_ty_span: _ } => { visitor.visit_expr(&visitor.thir()[source]) } + PlaceUnwrapUnsafeBinder { source } + | ValueUnwrapUnsafeBinder { source } + | WrapUnsafeBinder { source } => visitor.visit_expr(&visitor.thir()[source]), Closure(box ClosureExpr { closure_id: _, args: _, diff --git a/compiler/rustc_mir_build/messages.ftl b/compiler/rustc_mir_build/messages.ftl index 053775b4937..2c9a961b913 100644 --- a/compiler/rustc_mir_build/messages.ftl +++ b/compiler/rustc_mir_build/messages.ftl @@ -361,6 +361,18 @@ mir_build_unreachable_pattern = unreachable pattern .unreachable_pattern_let_binding = there is a binding of the same name; if you meant to pattern match against the value of that binding, that is a feature of constants that is not available for `let` bindings .suggestion = remove the match arm +mir_build_unsafe_binder_cast_requires_unsafe = + unsafe binder cast is unsafe and requires unsafe block + .label = unsafe binder cast + .note = casting to or from an `unsafe<...>` binder type is unsafe since it erases lifetime + information that may be required to uphold safety guarantees of a type + +mir_build_unsafe_binder_cast_requires_unsafe_unsafe_op_in_unsafe_fn_allowed = + unsafe binder cast is unsafe and requires unsafe block or unsafe fn + .label = unsafe binder cast + .note = casting to or from an `unsafe<...>` binder type is unsafe since it erases lifetime + information that may be required to uphold safety guarantees of a type + mir_build_unsafe_field_requires_unsafe = use of unsafe field is unsafe and requires unsafe block .note = unsafe fields may carry library invariants diff --git a/compiler/rustc_mir_build/src/builder/expr/as_place.rs b/compiler/rustc_mir_build/src/builder/expr/as_place.rs index 0086775e9f4..482f1e3840b 100644 --- a/compiler/rustc_mir_build/src/builder/expr/as_place.rs +++ b/compiler/rustc_mir_build/src/builder/expr/as_place.rs @@ -105,7 +105,8 @@ fn convert_to_hir_projections_and_truncate_for_capture( ProjectionElem::OpaqueCast(_) | ProjectionElem::Subtype(..) => continue, ProjectionElem::Index(..) | ProjectionElem::ConstantIndex { .. } - | ProjectionElem::Subslice { .. } => { + | ProjectionElem::Subslice { .. } + | ProjectionElem::UnwrapUnsafeBinder(_) => { // We don't capture array-access projections. // We can stop here as arrays are captured completely. break; @@ -523,6 +524,20 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { block.and(PlaceBuilder::from(temp)) } + ExprKind::PlaceUnwrapUnsafeBinder { source } => { + let place_builder = unpack!( + block = this.expr_as_place(block, source, mutability, fake_borrow_temps,) + ); + block.and(place_builder.project(PlaceElem::UnwrapUnsafeBinder(expr.ty))) + } + ExprKind::ValueUnwrapUnsafeBinder { source } => { + let source_expr = &this.thir[source]; + let temp = unpack!( + block = this.as_temp(block, source_expr.temp_lifetime, source, mutability) + ); + block.and(PlaceBuilder::from(temp).project(PlaceElem::UnwrapUnsafeBinder(expr.ty))) + } + ExprKind::Array { .. } | ExprKind::Tuple { .. } | ExprKind::Adt { .. } @@ -560,7 +575,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { | ExprKind::OffsetOf { .. } | ExprKind::Yield { .. } | ExprKind::ThreadLocalRef(_) - | ExprKind::Call { .. } => { + | ExprKind::Call { .. } + | ExprKind::WrapUnsafeBinder { .. } => { // these are not places, so we need to make a temporary. debug_assert!(!matches!(Category::of(&expr.kind), Some(Category::Place))); let temp = @@ -776,7 +792,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { | ProjectionElem::OpaqueCast(..) | ProjectionElem::Subtype(..) | ProjectionElem::ConstantIndex { .. } - | ProjectionElem::Subslice { .. } => (), + | ProjectionElem::Subslice { .. } + | ProjectionElem::UnwrapUnsafeBinder(_) => (), } } } diff --git a/compiler/rustc_mir_build/src/builder/expr/as_rvalue.rs b/compiler/rustc_mir_build/src/builder/expr/as_rvalue.rs index 9961c2488ef..e7713f0a1d6 100644 --- a/compiler/rustc_mir_build/src/builder/expr/as_rvalue.rs +++ b/compiler/rustc_mir_build/src/builder/expr/as_rvalue.rs @@ -508,6 +508,19 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { block.and(Rvalue::Use(Operand::Constant(Box::new(constant)))) } + ExprKind::WrapUnsafeBinder { source } => { + let source = unpack!( + block = this.as_operand( + block, + scope, + source, + LocalInfo::Boring, + NeedsTemporary::Maybe + ) + ); + block.and(Rvalue::WrapUnsafeBinder(source, expr.ty)) + } + ExprKind::Yield { .. } | ExprKind::Block { .. } | ExprKind::Match { .. } @@ -532,7 +545,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { | ExprKind::Become { .. } | ExprKind::InlineAsm { .. } | ExprKind::PlaceTypeAscription { .. } - | ExprKind::ValueTypeAscription { .. } => { + | ExprKind::ValueTypeAscription { .. } + | ExprKind::PlaceUnwrapUnsafeBinder { .. } + | ExprKind::ValueUnwrapUnsafeBinder { .. } => { // these do not have corresponding `Rvalue` variants, // so make an operand and then return that debug_assert!(!matches!( diff --git a/compiler/rustc_mir_build/src/builder/expr/category.rs b/compiler/rustc_mir_build/src/builder/expr/category.rs index e0349e3e3f6..ca55d36bfc6 100644 --- a/compiler/rustc_mir_build/src/builder/expr/category.rs +++ b/compiler/rustc_mir_build/src/builder/expr/category.rs @@ -41,7 +41,9 @@ impl Category { | ExprKind::UpvarRef { .. } | ExprKind::VarRef { .. } | ExprKind::PlaceTypeAscription { .. } - | ExprKind::ValueTypeAscription { .. } => Some(Category::Place), + | ExprKind::ValueTypeAscription { .. } + | ExprKind::PlaceUnwrapUnsafeBinder { .. } + | ExprKind::ValueUnwrapUnsafeBinder { .. } => Some(Category::Place), ExprKind::LogicalOp { .. } | ExprKind::Match { .. } @@ -68,7 +70,8 @@ impl Category { | ExprKind::Assign { .. } | ExprKind::AssignOp { .. } | ExprKind::ThreadLocalRef(_) - | ExprKind::OffsetOf { .. } => Some(Category::Rvalue(RvalueFunc::AsRvalue)), + | ExprKind::OffsetOf { .. } + | ExprKind::WrapUnsafeBinder { .. } => Some(Category::Rvalue(RvalueFunc::AsRvalue)), ExprKind::ConstBlock { .. } | ExprKind::Literal { .. } diff --git a/compiler/rustc_mir_build/src/builder/expr/into.rs b/compiler/rustc_mir_build/src/builder/expr/into.rs index 928156572d5..b25cd0f4426 100644 --- a/compiler/rustc_mir_build/src/builder/expr/into.rs +++ b/compiler/rustc_mir_build/src/builder/expr/into.rs @@ -554,7 +554,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ExprKind::VarRef { .. } | ExprKind::UpvarRef { .. } | ExprKind::PlaceTypeAscription { .. } - | ExprKind::ValueTypeAscription { .. } => { + | ExprKind::ValueTypeAscription { .. } + | ExprKind::PlaceUnwrapUnsafeBinder { .. } + | ExprKind::ValueUnwrapUnsafeBinder { .. } => { debug_assert!(Category::of(&expr.kind) == Some(Category::Place)); let place = unpack!(block = this.as_place(block, expr_id)); @@ -613,7 +615,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { | ExprKind::ConstParam { .. } | ExprKind::ThreadLocalRef(_) | ExprKind::StaticRef { .. } - | ExprKind::OffsetOf { .. } => { + | ExprKind::OffsetOf { .. } + | ExprKind::WrapUnsafeBinder { .. } => { debug_assert!(match Category::of(&expr.kind).unwrap() { // should be handled above Category::Rvalue(RvalueFunc::Into) => false, diff --git a/compiler/rustc_mir_build/src/check_unsafety.rs b/compiler/rustc_mir_build/src/check_unsafety.rs index 995bc311b7c..ee7f28c974b 100644 --- a/compiler/rustc_mir_build/src/check_unsafety.rs +++ b/compiler/rustc_mir_build/src/check_unsafety.rs @@ -439,6 +439,9 @@ impl<'a, 'tcx> Visitor<'a, 'tcx> for UnsafetyVisitor<'a, 'tcx> { | ExprKind::NeverToAny { .. } | ExprKind::PlaceTypeAscription { .. } | ExprKind::ValueTypeAscription { .. } + | ExprKind::PlaceUnwrapUnsafeBinder { .. } + | ExprKind::ValueUnwrapUnsafeBinder { .. } + | ExprKind::WrapUnsafeBinder { .. } | ExprKind::PointerCoercion { .. } | ExprKind::Repeat { .. } | ExprKind::StaticRef { .. } @@ -680,6 +683,11 @@ impl<'a, 'tcx> Visitor<'a, 'tcx> for UnsafetyVisitor<'a, 'tcx> { } } } + ExprKind::PlaceUnwrapUnsafeBinder { .. } + | ExprKind::ValueUnwrapUnsafeBinder { .. } + | ExprKind::WrapUnsafeBinder { .. } => { + self.requires_unsafe(expr.span, UnsafeBinderCast); + } _ => {} } visit::walk_expr(self, expr); @@ -728,6 +736,7 @@ enum UnsafeOpKind { /// (e.g., with `-C target-feature`). build_enabled: Vec<Symbol>, }, + UnsafeBinderCast, } use UnsafeOpKind::*; @@ -891,6 +900,15 @@ impl UnsafeOpKind { unsafe_not_inherited_note, }, ), + UnsafeBinderCast => tcx.emit_node_span_lint( + UNSAFE_OP_IN_UNSAFE_FN, + hir_id, + span, + UnsafeOpInUnsafeFnUnsafeBinderCastRequiresUnsafe { + span, + unsafe_not_inherited_note, + }, + ), } } @@ -1099,6 +1117,15 @@ impl UnsafeOpKind { function: tcx.def_path_str(*function), }); } + UnsafeBinderCast if unsafe_op_in_unsafe_fn_allowed => { + dcx.emit_err(UnsafeBinderCastRequiresUnsafeUnsafeOpInUnsafeFnAllowed { + span, + unsafe_not_inherited_note, + }); + } + UnsafeBinderCast => { + dcx.emit_err(UnsafeBinderCastRequiresUnsafe { span, unsafe_not_inherited_note }); + } } } } diff --git a/compiler/rustc_mir_build/src/errors.rs b/compiler/rustc_mir_build/src/errors.rs index 1f87bf0dbbb..e6aa191238a 100644 --- a/compiler/rustc_mir_build/src/errors.rs +++ b/compiler/rustc_mir_build/src/errors.rs @@ -161,6 +161,18 @@ pub(crate) struct UnsafeOpInUnsafeFnBorrowOfLayoutConstrainedFieldRequiresUnsafe } #[derive(LintDiagnostic)] +#[diag( + mir_build_unsafe_binder_cast_requires_unsafe, + code = E0133, +)] +pub(crate) struct UnsafeOpInUnsafeFnUnsafeBinderCastRequiresUnsafe { + #[label] + pub(crate) span: Span, + #[subdiagnostic] + pub(crate) unsafe_not_inherited_note: Option<UnsafeNotInheritedLintNote>, +} + +#[derive(LintDiagnostic)] #[diag(mir_build_unsafe_op_in_unsafe_fn_call_to_fn_with_requires_unsafe, code = E0133)] #[help] pub(crate) struct UnsafeOpInUnsafeFnCallToFunctionWithRequiresUnsafe { @@ -494,6 +506,32 @@ pub(crate) struct CallToFunctionWithRequiresUnsafeUnsafeOpInUnsafeFnAllowed { pub(crate) unsafe_not_inherited_note: Option<UnsafeNotInheritedNote>, } +#[derive(Diagnostic)] +#[diag( + mir_build_unsafe_binder_cast_requires_unsafe, + code = E0133, +)] +pub(crate) struct UnsafeBinderCastRequiresUnsafe { + #[primary_span] + #[label] + pub(crate) span: Span, + #[subdiagnostic] + pub(crate) unsafe_not_inherited_note: Option<UnsafeNotInheritedNote>, +} + +#[derive(Diagnostic)] +#[diag( + mir_build_unsafe_binder_cast_requires_unsafe_unsafe_op_in_unsafe_fn_allowed, + code = E0133, +)] +pub(crate) struct UnsafeBinderCastRequiresUnsafeUnsafeOpInUnsafeFnAllowed { + #[primary_span] + #[label] + pub(crate) span: Span, + #[subdiagnostic] + pub(crate) unsafe_not_inherited_note: Option<UnsafeNotInheritedNote>, +} + #[derive(Subdiagnostic)] #[label(mir_build_unsafe_not_inherited)] pub(crate) struct UnsafeNotInheritedNote { diff --git a/compiler/rustc_mir_build/src/thir/cx/expr.rs b/compiler/rustc_mir_build/src/thir/cx/expr.rs index 9cdf08d749b..795ac6b4bea 100644 --- a/compiler/rustc_mir_build/src/thir/cx/expr.rs +++ b/compiler/rustc_mir_build/src/thir/cx/expr.rs @@ -1,5 +1,6 @@ use itertools::Itertools; use rustc_abi::{FIRST_VARIANT, FieldIdx}; +use rustc_ast::UnsafeBinderCastKind; use rustc_data_structures::stack::ensure_sufficient_stack; use rustc_hir as hir; use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res}; @@ -910,8 +911,19 @@ impl<'tcx> Cx<'tcx> { } } - hir::ExprKind::UnsafeBinderCast(_kind, _source, _ty) => { - unreachable!("unsafe binders are not yet implemented") + hir::ExprKind::UnsafeBinderCast(UnsafeBinderCastKind::Unwrap, source, _ty) => { + // FIXME(unsafe_binders): Take into account the ascribed type, too. + let mirrored = self.mirror_expr(source); + if source.is_syntactic_place_expr() { + ExprKind::PlaceUnwrapUnsafeBinder { source: mirrored } + } else { + ExprKind::ValueUnwrapUnsafeBinder { source: mirrored } + } + } + hir::ExprKind::UnsafeBinderCast(UnsafeBinderCastKind::Wrap, source, _ty) => { + // FIXME(unsafe_binders): Take into account the ascribed type, too. + let mirrored = self.mirror_expr(source); + ExprKind::WrapUnsafeBinder { source: mirrored } } hir::ExprKind::DropTemps(source) => ExprKind::Use { source: self.mirror_expr(source) }, diff --git a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs index e0a1117f905..021edd50571 100644 --- a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs +++ b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs @@ -326,9 +326,10 @@ impl<'p, 'tcx> MatchVisitor<'p, 'tcx> { | Use { source } | PointerCoercion { source, .. } | PlaceTypeAscription { source, .. } - | ValueTypeAscription { source, .. } => { - self.is_known_valid_scrutinee(&self.thir()[*source]) - } + | ValueTypeAscription { source, .. } + | PlaceUnwrapUnsafeBinder { source } + | ValueUnwrapUnsafeBinder { source } + | WrapUnsafeBinder { source } => self.is_known_valid_scrutinee(&self.thir()[*source]), // These diverge. Become { .. } | Break { .. } | Continue { .. } | Return { .. } => true, diff --git a/compiler/rustc_mir_build/src/thir/print.rs b/compiler/rustc_mir_build/src/thir/print.rs index 228a64c2c70..729c8f784ba 100644 --- a/compiler/rustc_mir_build/src/thir/print.rs +++ b/compiler/rustc_mir_build/src/thir/print.rs @@ -477,6 +477,24 @@ impl<'a, 'tcx> ThirPrinter<'a, 'tcx> { self.print_expr(*source, depth_lvl + 2); print_indented!(self, "}", depth_lvl); } + PlaceUnwrapUnsafeBinder { source } => { + print_indented!(self, "PlaceUnwrapUnsafeBinder {", depth_lvl); + print_indented!(self, "source:", depth_lvl + 1); + self.print_expr(*source, depth_lvl + 2); + print_indented!(self, "}", depth_lvl); + } + ValueUnwrapUnsafeBinder { source } => { + print_indented!(self, "ValueUnwrapUnsafeBinder {", depth_lvl); + print_indented!(self, "source:", depth_lvl + 1); + self.print_expr(*source, depth_lvl + 2); + print_indented!(self, "}", depth_lvl); + } + WrapUnsafeBinder { source } => { + print_indented!(self, "WrapUnsafeBinder {", depth_lvl); + print_indented!(self, "source:", depth_lvl + 1); + self.print_expr(*source, depth_lvl + 2); + print_indented!(self, "}", depth_lvl); + } Closure(closure_expr) => { print_indented!(self, "Closure {", depth_lvl); print_indented!(self, "closure_expr:", depth_lvl + 1); diff --git a/compiler/rustc_mir_dataflow/src/impls/borrowed_locals.rs b/compiler/rustc_mir_dataflow/src/impls/borrowed_locals.rs index df4b1a53417..9abb8343432 100644 --- a/compiler/rustc_mir_dataflow/src/impls/borrowed_locals.rs +++ b/compiler/rustc_mir_dataflow/src/impls/borrowed_locals.rs @@ -97,7 +97,8 @@ where | Rvalue::UnaryOp(..) | Rvalue::Discriminant(..) | Rvalue::Aggregate(..) - | Rvalue::CopyForDeref(..) => {} + | Rvalue::CopyForDeref(..) + | Rvalue::WrapUnsafeBinder(..) => {} } } diff --git a/compiler/rustc_mir_dataflow/src/move_paths/abs_domain.rs b/compiler/rustc_mir_dataflow/src/move_paths/abs_domain.rs index d79d2c316ee..d056ad3d4b4 100644 --- a/compiler/rustc_mir_dataflow/src/move_paths/abs_domain.rs +++ b/compiler/rustc_mir_dataflow/src/move_paths/abs_domain.rs @@ -32,6 +32,7 @@ impl<'tcx> Lift for PlaceElem<'tcx> { } ProjectionElem::Downcast(a, u) => ProjectionElem::Downcast(a, u), ProjectionElem::Subtype(_ty) => ProjectionElem::Subtype(()), + ProjectionElem::UnwrapUnsafeBinder(_ty) => ProjectionElem::UnwrapUnsafeBinder(()), } } } diff --git a/compiler/rustc_mir_dataflow/src/move_paths/builder.rs b/compiler/rustc_mir_dataflow/src/move_paths/builder.rs index d1b3a389e9e..6e00e427a46 100644 --- a/compiler/rustc_mir_dataflow/src/move_paths/builder.rs +++ b/compiler/rustc_mir_dataflow/src/move_paths/builder.rs @@ -208,7 +208,7 @@ impl<'a, 'tcx, F: Fn(Ty<'tcx>) -> bool> MoveDataBuilder<'a, 'tcx, F> { | ty::Infer(_) | ty::Error(_) | ty::Placeholder(_) => bug!( - "When Place contains ProjectionElem::Field it's type shouldn't be {place_ty:#?}" + "When Place contains ProjectionElem::Field its type shouldn't be {place_ty:#?}" ), }, ProjectionElem::ConstantIndex { .. } | ProjectionElem::Subslice { .. } => { @@ -226,6 +226,7 @@ impl<'a, 'tcx, F: Fn(Ty<'tcx>) -> bool> MoveDataBuilder<'a, 'tcx, F> { } _ => bug!("Unexpected type {place_ty:#?}"), }, + ProjectionElem::UnwrapUnsafeBinder(_) => {} // `OpaqueCast`:Only transmutes the type, so no moves there. // `Downcast` :Only changes information about a `Place` without moving. // `Subtype` :Only transmutes the type, so moves. @@ -399,7 +400,8 @@ impl<'a, 'tcx, F: Fn(Ty<'tcx>) -> bool> MoveDataBuilder<'a, 'tcx, F> { | Rvalue::Repeat(ref operand, _) | Rvalue::Cast(_, ref operand, _) | Rvalue::ShallowInitBox(ref operand, _) - | Rvalue::UnaryOp(_, ref operand) => self.gather_operand(operand), + | Rvalue::UnaryOp(_, ref operand) + | Rvalue::WrapUnsafeBinder(ref operand, _) => self.gather_operand(operand), Rvalue::BinaryOp(ref _binop, box (ref lhs, ref rhs)) => { self.gather_operand(lhs); self.gather_operand(rhs); diff --git a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs index 8879e029346..90173da17f0 100644 --- a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs +++ b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs @@ -504,7 +504,8 @@ impl<'a, 'tcx> ConstAnalysis<'a, 'tcx> { | Rvalue::Cast(..) | Rvalue::BinaryOp(..) | Rvalue::Aggregate(..) - | Rvalue::ShallowInitBox(..) => { + | Rvalue::ShallowInitBox(..) + | Rvalue::WrapUnsafeBinder(..) => { // No modification is possible through these r-values. return ValueOrPlace::TOP; } diff --git a/compiler/rustc_mir_transform/src/dest_prop.rs b/compiler/rustc_mir_transform/src/dest_prop.rs index 41de1b58b91..7395ad496db 100644 --- a/compiler/rustc_mir_transform/src/dest_prop.rs +++ b/compiler/rustc_mir_transform/src/dest_prop.rs @@ -575,6 +575,9 @@ impl WriteInfo { self.add_operand(op); } } + Rvalue::WrapUnsafeBinder(op, _) => { + self.add_operand(op); + } Rvalue::ThreadLocalRef(_) | Rvalue::NullaryOp(_, _) | Rvalue::Ref(_, _, _) diff --git a/compiler/rustc_mir_transform/src/gvn.rs b/compiler/rustc_mir_transform/src/gvn.rs index 16e15fa12e0..c261e25100d 100644 --- a/compiler/rustc_mir_transform/src/gvn.rs +++ b/compiler/rustc_mir_transform/src/gvn.rs @@ -476,6 +476,9 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { } ProjectionElem::OpaqueCast(ty) => ProjectionElem::OpaqueCast(ty), ProjectionElem::Subtype(ty) => ProjectionElem::Subtype(ty), + ProjectionElem::UnwrapUnsafeBinder(ty) => { + ProjectionElem::UnwrapUnsafeBinder(ty) + } // This should have been replaced by a `ConstantIndex` earlier. ProjectionElem::Index(_) => return None, }; @@ -713,6 +716,7 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { } ProjectionElem::OpaqueCast(ty) => ProjectionElem::OpaqueCast(ty), ProjectionElem::Subtype(ty) => ProjectionElem::Subtype(ty), + ProjectionElem::UnwrapUnsafeBinder(ty) => ProjectionElem::UnwrapUnsafeBinder(ty), }; Some(self.insert(Value::Projection(value, proj))) @@ -867,6 +871,9 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { self.simplify_place_projection(place, location); return self.new_pointer(*place, AddressKind::Address(mutbl)); } + Rvalue::WrapUnsafeBinder(ref mut op, _) => { + return self.simplify_operand(op, location); + } // Operations. Rvalue::Len(ref mut place) => return self.simplify_len(place, location), @@ -931,6 +938,7 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { ProjectionElem::Downcast(symbol, idx) => ProjectionElem::Downcast(symbol, idx), ProjectionElem::OpaqueCast(idx) => ProjectionElem::OpaqueCast(idx), ProjectionElem::Subtype(idx) => ProjectionElem::Subtype(idx), + ProjectionElem::UnwrapUnsafeBinder(ty) => ProjectionElem::UnwrapUnsafeBinder(ty), }) } diff --git a/compiler/rustc_mir_transform/src/known_panics_lint.rs b/compiler/rustc_mir_transform/src/known_panics_lint.rs index f4ac5c6aa80..2864cc0b9fe 100644 --- a/compiler/rustc_mir_transform/src/known_panics_lint.rs +++ b/compiler/rustc_mir_transform/src/known_panics_lint.rs @@ -444,7 +444,8 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> { | Rvalue::Cast(..) | Rvalue::ShallowInitBox(..) | Rvalue::Discriminant(..) - | Rvalue::NullaryOp(..) => {} + | Rvalue::NullaryOp(..) + | Rvalue::WrapUnsafeBinder(..) => {} } // FIXME we need to revisit this for #67176 @@ -546,7 +547,9 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> { let val: Value<'_> = match *rvalue { ThreadLocalRef(_) => return None, - Use(ref operand) => self.eval_operand(operand)?.into(), + Use(ref operand) | WrapUnsafeBinder(ref operand, _) => { + self.eval_operand(operand)?.into() + } CopyForDeref(place) => self.eval_place(place)?.into(), diff --git a/compiler/rustc_mir_transform/src/promote_consts.rs b/compiler/rustc_mir_transform/src/promote_consts.rs index 6aa3343bb6e..9101c9bfc9a 100644 --- a/compiler/rustc_mir_transform/src/promote_consts.rs +++ b/compiler/rustc_mir_transform/src/promote_consts.rs @@ -293,7 +293,8 @@ impl<'tcx> Validator<'_, 'tcx> { // Recurse directly. ProjectionElem::ConstantIndex { .. } | ProjectionElem::Subtype(_) - | ProjectionElem::Subslice { .. } => {} + | ProjectionElem::Subslice { .. } + | ProjectionElem::UnwrapUnsafeBinder(_) => {} // Never recurse. ProjectionElem::OpaqueCast(..) | ProjectionElem::Downcast(..) => { @@ -426,7 +427,9 @@ impl<'tcx> Validator<'_, 'tcx> { fn validate_rvalue(&mut self, rvalue: &Rvalue<'tcx>) -> Result<(), Unpromotable> { match rvalue { - Rvalue::Use(operand) | Rvalue::Repeat(operand, _) => { + Rvalue::Use(operand) + | Rvalue::Repeat(operand, _) + | Rvalue::WrapUnsafeBinder(operand, _) => { self.validate_operand(operand)?; } Rvalue::CopyForDeref(place) => { diff --git a/compiler/rustc_mir_transform/src/validate.rs b/compiler/rustc_mir_transform/src/validate.rs index 5881264cba5..e282eaf761c 100644 --- a/compiler/rustc_mir_transform/src/validate.rs +++ b/compiler/rustc_mir_transform/src/validate.rs @@ -807,6 +807,25 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> { ) } } + ProjectionElem::UnwrapUnsafeBinder(unwrapped_ty) => { + let binder_ty = place_ref.ty(&self.body.local_decls, self.tcx); + let ty::UnsafeBinder(binder_ty) = *binder_ty.ty.kind() else { + self.fail( + location, + format!("WrapUnsafeBinder does not produce a ty::UnsafeBinder"), + ); + return; + }; + let binder_inner_ty = self.tcx.instantiate_bound_regions_with_erased(*binder_ty); + if !self.mir_assign_valid_types(unwrapped_ty, binder_inner_ty) { + self.fail( + location, + format!( + "Cannot unwrap unsafe binder {binder_ty:?} into type {unwrapped_ty:?}" + ), + ); + } + } _ => {} } self.super_projection_elem(place_ref, elem, context, location); @@ -1362,6 +1381,24 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> { | Rvalue::RawPtr(_, _) | Rvalue::NullaryOp(NullOp::SizeOf | NullOp::AlignOf | NullOp::UbChecks, _) | Rvalue::Discriminant(_) => {} + + Rvalue::WrapUnsafeBinder(op, ty) => { + let unwrapped_ty = op.ty(self.body, self.tcx); + let ty::UnsafeBinder(binder_ty) = *ty.kind() else { + self.fail( + location, + format!("WrapUnsafeBinder does not produce a ty::UnsafeBinder"), + ); + return; + }; + let binder_inner_ty = self.tcx.instantiate_bound_regions_with_erased(*binder_ty); + if !self.mir_assign_valid_types(unwrapped_ty, binder_inner_ty) { + self.fail( + location, + format!("Cannot wrap {unwrapped_ty:?} into unsafe binder {binder_ty:?}"), + ); + } + } } self.super_rvalue(rvalue, location); } diff --git a/compiler/rustc_passes/src/liveness.rs b/compiler/rustc_passes/src/liveness.rs index 73da8855e10..60f7616a5fb 100644 --- a/compiler/rustc_passes/src/liveness.rs +++ b/compiler/rustc_passes/src/liveness.rs @@ -1522,6 +1522,14 @@ impl<'tcx> Liveness<'_, 'tcx> { } fn warn_about_unused_args(&self, body: &hir::Body<'_>, entry_ln: LiveNode) { + if let Some(intrinsic) = + self.ir.tcx.intrinsic(self.ir.tcx.hir().body_owner_def_id(body.id())) + { + if intrinsic.must_be_overridden { + return; + } + } + for p in body.params { self.check_unused_vars_in_pat( p.pat, diff --git a/compiler/rustc_smir/src/rustc_smir/convert/mir.rs b/compiler/rustc_smir/src/rustc_smir/convert/mir.rs index 150ec02b7db..4a0420cc603 100644 --- a/compiler/rustc_smir/src/rustc_smir/convert/mir.rs +++ b/compiler/rustc_smir/src/rustc_smir/convert/mir.rs @@ -217,6 +217,7 @@ impl<'tcx> Stable<'tcx> for mir::Rvalue<'tcx> { stable_mir::mir::Rvalue::ShallowInitBox(op.stable(tables), ty.stable(tables)) } CopyForDeref(place) => stable_mir::mir::Rvalue::CopyForDeref(place.stable(tables)), + WrapUnsafeBinder(..) => todo!("FIXME(unsafe_binders):"), } } } @@ -395,6 +396,7 @@ impl<'tcx> Stable<'tcx> for mir::PlaceElem<'tcx> { Downcast(_, idx) => stable_mir::mir::ProjectionElem::Downcast(idx.stable(tables)), OpaqueCast(ty) => stable_mir::mir::ProjectionElem::OpaqueCast(ty.stable(tables)), Subtype(ty) => stable_mir::mir::ProjectionElem::Subtype(ty.stable(tables)), + UnwrapUnsafeBinder(..) => todo!("FIXME(unsafe_binders):"), } } } diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index 7f7b460cf57..322da939011 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -2152,7 +2152,6 @@ symbols! { unwrap, unwrap_binder, unwrap_or, - unwrap_unsafe_binder, use_extern_macros, use_nested_groups, used, diff --git a/compiler/rustc_trait_selection/src/solve/delegate.rs b/compiler/rustc_trait_selection/src/solve/delegate.rs index acd00d9f74f..abb79493432 100644 --- a/compiler/rustc_trait_selection/src/solve/delegate.rs +++ b/compiler/rustc_trait_selection/src/solve/delegate.rs @@ -1,7 +1,7 @@ use std::ops::Deref; use rustc_data_structures::fx::FxHashSet; -use rustc_hir::def_id::DefId; +use rustc_hir::def_id::{CRATE_DEF_ID, DefId}; use rustc_infer::infer::canonical::query_response::make_query_region_constraints; use rustc_infer::infer::canonical::{ Canonical, CanonicalExt as _, CanonicalQueryInput, CanonicalVarInfo, CanonicalVarValues, @@ -98,9 +98,10 @@ impl<'tcx> rustc_next_trait_solver::delegate::SolverDelegate for SolverDelegate< param_env: ty::ParamEnv<'tcx>, arg: ty::GenericArg<'tcx>, ) -> Option<Vec<Goal<'tcx, ty::Predicate<'tcx>>>> { - crate::traits::wf::unnormalized_obligations(&self.0, param_env, arg).map(|obligations| { - obligations.into_iter().map(|obligation| obligation.into()).collect() - }) + crate::traits::wf::unnormalized_obligations(&self.0, param_env, arg, DUMMY_SP, CRATE_DEF_ID) + .map(|obligations| { + obligations.into_iter().map(|obligation| obligation.into()).collect() + }) } fn clone_opaque_types_for_query_response(&self) -> Vec<(ty::OpaqueTypeKey<'tcx>, Ty<'tcx>)> { diff --git a/compiler/rustc_trait_selection/src/solve/fulfill.rs b/compiler/rustc_trait_selection/src/solve/fulfill.rs index c8ae977b5ad..0db44eda847 100644 --- a/compiler/rustc_trait_selection/src/solve/fulfill.rs +++ b/compiler/rustc_trait_selection/src/solve/fulfill.rs @@ -1,25 +1,21 @@ use std::marker::PhantomData; use std::mem; -use std::ops::ControlFlow; use rustc_data_structures::thinvec::ExtractIf; use rustc_infer::infer::InferCtxt; use rustc_infer::traits::query::NoSolution; -use rustc_infer::traits::solve::{CandidateSource, GoalSource, MaybeCause}; use rustc_infer::traits::{ - self, FromSolverError, MismatchedProjectionTypes, Obligation, ObligationCause, - ObligationCauseCode, PredicateObligation, PredicateObligations, SelectionError, TraitEngine, + FromSolverError, PredicateObligation, PredicateObligations, TraitEngine, }; -use rustc_middle::ty::error::{ExpectedFound, TypeError}; -use rustc_middle::ty::{self, TyCtxt}; -use rustc_middle::{bug, span_bug}; use rustc_next_trait_solver::solve::{GenerateProofTree, HasChanged, SolverDelegateEvalExt as _}; -use tracing::{instrument, trace}; +use tracing::instrument; +use self::derive_errors::*; use super::Certainty; use super::delegate::SolverDelegate; -use super::inspect::{self, ProofTreeInferCtxtExt, ProofTreeVisitor}; -use crate::traits::{FulfillmentError, FulfillmentErrorCode, ScrubbedTraitError}; +use crate::traits::{FulfillmentError, ScrubbedTraitError}; + +mod derive_errors; /// A trait engine using the new trait solver. /// @@ -244,483 +240,3 @@ impl<'tcx> FromSolverError<'tcx, NextSolverError<'tcx>> for ScrubbedTraitError<' } } } - -fn fulfillment_error_for_no_solution<'tcx>( - infcx: &InferCtxt<'tcx>, - root_obligation: PredicateObligation<'tcx>, -) -> FulfillmentError<'tcx> { - let obligation = find_best_leaf_obligation(infcx, &root_obligation, false); - - let code = match obligation.predicate.kind().skip_binder() { - ty::PredicateKind::Clause(ty::ClauseKind::Projection(_)) => { - FulfillmentErrorCode::Project( - // FIXME: This could be a `Sorts` if the term is a type - MismatchedProjectionTypes { err: TypeError::Mismatch }, - ) - } - ty::PredicateKind::Clause(ty::ClauseKind::ConstArgHasType(ct, expected_ty)) => { - let ct_ty = match ct.kind() { - ty::ConstKind::Unevaluated(uv) => { - infcx.tcx.type_of(uv.def).instantiate(infcx.tcx, uv.args) - } - ty::ConstKind::Param(param_ct) => param_ct.find_ty_from_env(obligation.param_env), - ty::ConstKind::Value(cv) => cv.ty, - kind => span_bug!( - obligation.cause.span, - "ConstArgHasWrongType failed but we don't know how to compute type for {kind:?}" - ), - }; - FulfillmentErrorCode::Select(SelectionError::ConstArgHasWrongType { - ct, - ct_ty, - expected_ty, - }) - } - ty::PredicateKind::NormalizesTo(..) => { - FulfillmentErrorCode::Project(MismatchedProjectionTypes { err: TypeError::Mismatch }) - } - ty::PredicateKind::AliasRelate(_, _, _) => { - FulfillmentErrorCode::Project(MismatchedProjectionTypes { err: TypeError::Mismatch }) - } - ty::PredicateKind::Subtype(pred) => { - let (a, b) = infcx.enter_forall_and_leak_universe( - obligation.predicate.kind().rebind((pred.a, pred.b)), - ); - let expected_found = ExpectedFound::new(a, b); - FulfillmentErrorCode::Subtype(expected_found, TypeError::Sorts(expected_found)) - } - ty::PredicateKind::Coerce(pred) => { - let (a, b) = infcx.enter_forall_and_leak_universe( - obligation.predicate.kind().rebind((pred.a, pred.b)), - ); - let expected_found = ExpectedFound::new(b, a); - FulfillmentErrorCode::Subtype(expected_found, TypeError::Sorts(expected_found)) - } - ty::PredicateKind::Clause(_) - | ty::PredicateKind::DynCompatible(_) - | ty::PredicateKind::Ambiguous => { - FulfillmentErrorCode::Select(SelectionError::Unimplemented) - } - ty::PredicateKind::ConstEquate(..) => { - bug!("unexpected goal: {obligation:?}") - } - }; - - FulfillmentError { obligation, code, root_obligation } -} - -fn fulfillment_error_for_stalled<'tcx>( - infcx: &InferCtxt<'tcx>, - root_obligation: PredicateObligation<'tcx>, -) -> FulfillmentError<'tcx> { - let (code, refine_obligation) = infcx.probe(|_| { - match <&SolverDelegate<'tcx>>::from(infcx) - .evaluate_root_goal(root_obligation.clone().into(), GenerateProofTree::No) - .0 - { - Ok((_, Certainty::Maybe(MaybeCause::Ambiguity))) => { - (FulfillmentErrorCode::Ambiguity { overflow: None }, true) - } - Ok((_, Certainty::Maybe(MaybeCause::Overflow { suggest_increasing_limit }))) => ( - FulfillmentErrorCode::Ambiguity { overflow: Some(suggest_increasing_limit) }, - // Don't look into overflows because we treat overflows weirdly anyways. - // We discard the inference constraints from overflowing goals, so - // recomputing the goal again during `find_best_leaf_obligation` may apply - // inference guidance that makes other goals go from ambig -> pass, for example. - // - // FIXME: We should probably just look into overflows here. - false, - ), - Ok((_, Certainty::Yes)) => { - bug!("did not expect successful goal when collecting ambiguity errors") - } - Err(_) => { - bug!("did not expect selection error when collecting ambiguity errors") - } - } - }); - - FulfillmentError { - obligation: if refine_obligation { - find_best_leaf_obligation(infcx, &root_obligation, true) - } else { - root_obligation.clone() - }, - code, - root_obligation, - } -} - -fn fulfillment_error_for_overflow<'tcx>( - infcx: &InferCtxt<'tcx>, - root_obligation: PredicateObligation<'tcx>, -) -> FulfillmentError<'tcx> { - FulfillmentError { - obligation: find_best_leaf_obligation(infcx, &root_obligation, true), - code: FulfillmentErrorCode::Ambiguity { overflow: Some(true) }, - root_obligation, - } -} - -fn find_best_leaf_obligation<'tcx>( - infcx: &InferCtxt<'tcx>, - obligation: &PredicateObligation<'tcx>, - consider_ambiguities: bool, -) -> PredicateObligation<'tcx> { - let obligation = infcx.resolve_vars_if_possible(obligation.clone()); - // FIXME: we use a probe here as the `BestObligation` visitor does not - // check whether it uses candidates which get shadowed by where-bounds. - // - // We should probably fix the visitor to not do so instead, as this also - // means the leaf obligation may be incorrect. - infcx - .fudge_inference_if_ok(|| { - infcx - .visit_proof_tree(obligation.clone().into(), &mut BestObligation { - obligation: obligation.clone(), - consider_ambiguities, - }) - .break_value() - .ok_or(()) - }) - .unwrap_or(obligation) -} - -struct BestObligation<'tcx> { - obligation: PredicateObligation<'tcx>, - consider_ambiguities: bool, -} - -impl<'tcx> BestObligation<'tcx> { - fn with_derived_obligation( - &mut self, - derived_obligation: PredicateObligation<'tcx>, - and_then: impl FnOnce(&mut Self) -> <Self as ProofTreeVisitor<'tcx>>::Result, - ) -> <Self as ProofTreeVisitor<'tcx>>::Result { - let old_obligation = std::mem::replace(&mut self.obligation, derived_obligation); - let res = and_then(self); - self.obligation = old_obligation; - res - } - - /// Filter out the candidates that aren't interesting to visit for the - /// purposes of reporting errors. For ambiguities, we only consider - /// candidates that may hold. For errors, we only consider candidates that - /// *don't* hold and which have impl-where clauses that also don't hold. - fn non_trivial_candidates<'a>( - &self, - goal: &'a inspect::InspectGoal<'a, 'tcx>, - ) -> Vec<inspect::InspectCandidate<'a, 'tcx>> { - let mut candidates = goal.candidates(); - match self.consider_ambiguities { - true => { - // If we have an ambiguous obligation, we must consider *all* candidates - // that hold, or else we may guide inference causing other goals to go - // from ambig -> pass/fail. - candidates.retain(|candidate| candidate.result().is_ok()); - } - false => { - // If we have >1 candidate, one may still be due to "boring" reasons, like - // an alias-relate that failed to hold when deeply evaluated. We really - // don't care about reasons like this. - if candidates.len() > 1 { - candidates.retain(|candidate| { - goal.infcx().probe(|_| { - candidate.instantiate_nested_goals(self.span()).iter().any( - |nested_goal| { - matches!( - nested_goal.source(), - GoalSource::ImplWhereBound - | GoalSource::AliasBoundConstCondition - | GoalSource::InstantiateHigherRanked - | GoalSource::AliasWellFormed - ) && match self.consider_ambiguities { - true => { - matches!( - nested_goal.result(), - Ok(Certainty::Maybe(MaybeCause::Ambiguity)) - ) - } - false => matches!(nested_goal.result(), Err(_)), - } - }, - ) - }) - }); - } - - // Prefer a non-rigid candidate if there is one. - if candidates.len() > 1 { - candidates.retain(|candidate| { - !matches!(candidate.kind(), inspect::ProbeKind::RigidAlias { .. }) - }); - } - } - } - - candidates - } -} - -impl<'tcx> ProofTreeVisitor<'tcx> for BestObligation<'tcx> { - type Result = ControlFlow<PredicateObligation<'tcx>>; - - fn span(&self) -> rustc_span::Span { - self.obligation.cause.span - } - - #[instrument(level = "trace", skip(self, goal), fields(goal = ?goal.goal()))] - fn visit_goal(&mut self, goal: &inspect::InspectGoal<'_, 'tcx>) -> Self::Result { - let candidates = self.non_trivial_candidates(goal); - trace!(candidates = ?candidates.iter().map(|c| c.kind()).collect::<Vec<_>>()); - - let [candidate] = candidates.as_slice() else { - return ControlFlow::Break(self.obligation.clone()); - }; - - // Don't walk into impls that have `do_not_recommend`. - if let inspect::ProbeKind::TraitCandidate { - source: CandidateSource::Impl(impl_def_id), - result: _, - } = candidate.kind() - && goal.infcx().tcx.do_not_recommend_impl(impl_def_id) - { - return ControlFlow::Break(self.obligation.clone()); - } - - let tcx = goal.infcx().tcx; - // FIXME: Also, what about considering >1 layer up the stack? May be necessary - // for normalizes-to. - let pred_kind = goal.goal().predicate.kind(); - let child_mode = match pred_kind.skip_binder() { - ty::PredicateKind::Clause(ty::ClauseKind::Trait(pred)) => { - ChildMode::Trait(pred_kind.rebind(pred)) - } - ty::PredicateKind::Clause(ty::ClauseKind::HostEffect(pred)) => { - ChildMode::Host(pred_kind.rebind(pred)) - } - ty::PredicateKind::NormalizesTo(normalizes_to) - if matches!( - normalizes_to.alias.kind(tcx), - ty::AliasTermKind::ProjectionTy | ty::AliasTermKind::ProjectionConst - ) => - { - ChildMode::Trait(pred_kind.rebind(ty::TraitPredicate { - trait_ref: normalizes_to.alias.trait_ref(tcx), - polarity: ty::PredicatePolarity::Positive, - })) - } - _ => ChildMode::PassThrough, - }; - - let nested_goals = candidate.instantiate_nested_goals(self.span()); - - // If the candidate requires some `T: FnPtr` bound which does not hold should not be treated as - // an actual candidate, instead we should treat them as if the impl was never considered to - // have potentially applied. As if `impl<A, R> Trait for for<..> fn(..A) -> R` was written - // instead of `impl<T: FnPtr> Trait for T`. - // - // We do this as a separate loop so that we do not choose to tell the user about some nested - // goal before we encounter a `T: FnPtr` nested goal. - for nested_goal in &nested_goals { - if let Some(fn_ptr_trait) = tcx.lang_items().fn_ptr_trait() - && let Some(poly_trait_pred) = nested_goal.goal().predicate.as_trait_clause() - && poly_trait_pred.def_id() == fn_ptr_trait - && let Err(NoSolution) = nested_goal.result() - { - return ControlFlow::Break(self.obligation.clone()); - } - } - - let mut impl_where_bound_count = 0; - for nested_goal in nested_goals { - trace!(nested_goal = ?(nested_goal.goal(), nested_goal.source(), nested_goal.result())); - - let make_obligation = |cause| Obligation { - cause, - param_env: nested_goal.goal().param_env, - predicate: nested_goal.goal().predicate, - recursion_depth: self.obligation.recursion_depth + 1, - }; - - let obligation; - match (child_mode, nested_goal.source()) { - (ChildMode::Trait(_) | ChildMode::Host(_), GoalSource::Misc) => { - continue; - } - (ChildMode::Trait(parent_trait_pred), GoalSource::ImplWhereBound) => { - obligation = make_obligation(derive_cause( - tcx, - candidate.kind(), - self.obligation.cause.clone(), - impl_where_bound_count, - parent_trait_pred, - )); - impl_where_bound_count += 1; - } - ( - ChildMode::Host(parent_host_pred), - GoalSource::ImplWhereBound | GoalSource::AliasBoundConstCondition, - ) => { - obligation = make_obligation(derive_host_cause( - tcx, - candidate.kind(), - self.obligation.cause.clone(), - impl_where_bound_count, - parent_host_pred, - )); - impl_where_bound_count += 1; - } - // Skip over a higher-ranked predicate. - (_, GoalSource::InstantiateHigherRanked) => { - obligation = self.obligation.clone(); - } - (ChildMode::PassThrough, _) - | (_, GoalSource::AliasWellFormed | GoalSource::AliasBoundConstCondition) => { - obligation = make_obligation(self.obligation.cause.clone()); - } - } - - // Skip nested goals that aren't the *reason* for our goal's failure. - match self.consider_ambiguities { - true if matches!( - nested_goal.result(), - Ok(Certainty::Maybe(MaybeCause::Ambiguity)) - ) => {} - false if matches!(nested_goal.result(), Err(_)) => {} - _ => continue, - } - - self.with_derived_obligation(obligation, |this| nested_goal.visit_with(this))?; - } - - // alias-relate may fail because the lhs or rhs can't be normalized, - // and therefore is treated as rigid. - if let Some(ty::PredicateKind::AliasRelate(lhs, rhs, _)) = pred_kind.no_bound_vars() { - if let Some(obligation) = goal - .infcx() - .visit_proof_tree_at_depth( - goal.goal().with(goal.infcx().tcx, ty::ClauseKind::WellFormed(lhs.into())), - goal.depth() + 1, - self, - ) - .break_value() - { - return ControlFlow::Break(obligation); - } else if let Some(obligation) = goal - .infcx() - .visit_proof_tree_at_depth( - goal.goal().with(goal.infcx().tcx, ty::ClauseKind::WellFormed(rhs.into())), - goal.depth() + 1, - self, - ) - .break_value() - { - return ControlFlow::Break(obligation); - } - } - - ControlFlow::Break(self.obligation.clone()) - } -} - -#[derive(Debug, Copy, Clone)] -enum ChildMode<'tcx> { - // Try to derive an `ObligationCause::{ImplDerived,BuiltinDerived}`, - // and skip all `GoalSource::Misc`, which represent useless obligations - // such as alias-eq which may not hold. - Trait(ty::PolyTraitPredicate<'tcx>), - // Try to derive an `ObligationCause::{ImplDerived,BuiltinDerived}`, - // and skip all `GoalSource::Misc`, which represent useless obligations - // such as alias-eq which may not hold. - Host(ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>), - // Skip trying to derive an `ObligationCause` from this obligation, and - // report *all* sub-obligations as if they came directly from the parent - // obligation. - PassThrough, -} - -fn derive_cause<'tcx>( - tcx: TyCtxt<'tcx>, - candidate_kind: inspect::ProbeKind<TyCtxt<'tcx>>, - mut cause: ObligationCause<'tcx>, - idx: usize, - parent_trait_pred: ty::PolyTraitPredicate<'tcx>, -) -> ObligationCause<'tcx> { - match candidate_kind { - inspect::ProbeKind::TraitCandidate { - source: CandidateSource::Impl(impl_def_id), - result: _, - } => { - if let Some((_, span)) = - tcx.predicates_of(impl_def_id).instantiate_identity(tcx).iter().nth(idx) - { - cause = cause.derived_cause(parent_trait_pred, |derived| { - ObligationCauseCode::ImplDerived(Box::new(traits::ImplDerivedCause { - derived, - impl_or_alias_def_id: impl_def_id, - impl_def_predicate_index: Some(idx), - span, - })) - }) - } - } - inspect::ProbeKind::TraitCandidate { - source: CandidateSource::BuiltinImpl(..), - result: _, - } => { - cause = cause.derived_cause(parent_trait_pred, ObligationCauseCode::BuiltinDerived); - } - _ => {} - }; - cause -} - -fn derive_host_cause<'tcx>( - tcx: TyCtxt<'tcx>, - candidate_kind: inspect::ProbeKind<TyCtxt<'tcx>>, - mut cause: ObligationCause<'tcx>, - idx: usize, - parent_host_pred: ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>, -) -> ObligationCause<'tcx> { - match candidate_kind { - inspect::ProbeKind::TraitCandidate { - source: CandidateSource::Impl(impl_def_id), - result: _, - } => { - if let Some((_, span)) = tcx - .predicates_of(impl_def_id) - .instantiate_identity(tcx) - .into_iter() - .chain(tcx.const_conditions(impl_def_id).instantiate_identity(tcx).into_iter().map( - |(trait_ref, span)| { - ( - trait_ref.to_host_effect_clause( - tcx, - parent_host_pred.skip_binder().constness, - ), - span, - ) - }, - )) - .nth(idx) - { - cause = - cause.derived_host_cause(parent_host_pred, |derived| { - ObligationCauseCode::ImplDerivedHost(Box::new( - traits::ImplDerivedHostCause { derived, impl_def_id, span }, - )) - }) - } - } - inspect::ProbeKind::TraitCandidate { - source: CandidateSource::BuiltinImpl(..), - result: _, - } => { - cause = - cause.derived_host_cause(parent_host_pred, ObligationCauseCode::BuiltinDerivedHost); - } - _ => {} - }; - cause -} diff --git a/compiler/rustc_trait_selection/src/solve/fulfill/derive_errors.rs b/compiler/rustc_trait_selection/src/solve/fulfill/derive_errors.rs new file mode 100644 index 00000000000..c64bc19835b --- /dev/null +++ b/compiler/rustc_trait_selection/src/solve/fulfill/derive_errors.rs @@ -0,0 +1,527 @@ +use std::ops::ControlFlow; + +use rustc_infer::infer::InferCtxt; +use rustc_infer::traits::solve::{CandidateSource, GoalSource, MaybeCause}; +use rustc_infer::traits::{ + self, MismatchedProjectionTypes, Obligation, ObligationCause, ObligationCauseCode, + PredicateObligation, SelectionError, +}; +use rustc_middle::ty::error::{ExpectedFound, TypeError}; +use rustc_middle::ty::{self, TyCtxt}; +use rustc_middle::{bug, span_bug}; +use rustc_next_trait_solver::solve::{GenerateProofTree, SolverDelegateEvalExt as _}; +use rustc_type_ir::solve::{Goal, NoSolution}; +use tracing::{instrument, trace}; + +use crate::solve::Certainty; +use crate::solve::delegate::SolverDelegate; +use crate::solve::inspect::{self, ProofTreeInferCtxtExt, ProofTreeVisitor}; +use crate::traits::{FulfillmentError, FulfillmentErrorCode, wf}; + +pub(super) fn fulfillment_error_for_no_solution<'tcx>( + infcx: &InferCtxt<'tcx>, + root_obligation: PredicateObligation<'tcx>, +) -> FulfillmentError<'tcx> { + let obligation = find_best_leaf_obligation(infcx, &root_obligation, false); + + let code = match obligation.predicate.kind().skip_binder() { + ty::PredicateKind::Clause(ty::ClauseKind::Projection(_)) => { + FulfillmentErrorCode::Project( + // FIXME: This could be a `Sorts` if the term is a type + MismatchedProjectionTypes { err: TypeError::Mismatch }, + ) + } + ty::PredicateKind::Clause(ty::ClauseKind::ConstArgHasType(ct, expected_ty)) => { + let ct_ty = match ct.kind() { + ty::ConstKind::Unevaluated(uv) => { + infcx.tcx.type_of(uv.def).instantiate(infcx.tcx, uv.args) + } + ty::ConstKind::Param(param_ct) => param_ct.find_ty_from_env(obligation.param_env), + ty::ConstKind::Value(cv) => cv.ty, + kind => span_bug!( + obligation.cause.span, + "ConstArgHasWrongType failed but we don't know how to compute type for {kind:?}" + ), + }; + FulfillmentErrorCode::Select(SelectionError::ConstArgHasWrongType { + ct, + ct_ty, + expected_ty, + }) + } + ty::PredicateKind::NormalizesTo(..) => { + FulfillmentErrorCode::Project(MismatchedProjectionTypes { err: TypeError::Mismatch }) + } + ty::PredicateKind::AliasRelate(_, _, _) => { + FulfillmentErrorCode::Project(MismatchedProjectionTypes { err: TypeError::Mismatch }) + } + ty::PredicateKind::Subtype(pred) => { + let (a, b) = infcx.enter_forall_and_leak_universe( + obligation.predicate.kind().rebind((pred.a, pred.b)), + ); + let expected_found = ExpectedFound::new(a, b); + FulfillmentErrorCode::Subtype(expected_found, TypeError::Sorts(expected_found)) + } + ty::PredicateKind::Coerce(pred) => { + let (a, b) = infcx.enter_forall_and_leak_universe( + obligation.predicate.kind().rebind((pred.a, pred.b)), + ); + let expected_found = ExpectedFound::new(b, a); + FulfillmentErrorCode::Subtype(expected_found, TypeError::Sorts(expected_found)) + } + ty::PredicateKind::Clause(_) + | ty::PredicateKind::DynCompatible(_) + | ty::PredicateKind::Ambiguous => { + FulfillmentErrorCode::Select(SelectionError::Unimplemented) + } + ty::PredicateKind::ConstEquate(..) => { + bug!("unexpected goal: {obligation:?}") + } + }; + + FulfillmentError { obligation, code, root_obligation } +} + +pub(super) fn fulfillment_error_for_stalled<'tcx>( + infcx: &InferCtxt<'tcx>, + root_obligation: PredicateObligation<'tcx>, +) -> FulfillmentError<'tcx> { + let (code, refine_obligation) = infcx.probe(|_| { + match <&SolverDelegate<'tcx>>::from(infcx) + .evaluate_root_goal(root_obligation.clone().into(), GenerateProofTree::No) + .0 + { + Ok((_, Certainty::Maybe(MaybeCause::Ambiguity))) => { + (FulfillmentErrorCode::Ambiguity { overflow: None }, true) + } + Ok((_, Certainty::Maybe(MaybeCause::Overflow { suggest_increasing_limit }))) => ( + FulfillmentErrorCode::Ambiguity { overflow: Some(suggest_increasing_limit) }, + // Don't look into overflows because we treat overflows weirdly anyways. + // We discard the inference constraints from overflowing goals, so + // recomputing the goal again during `find_best_leaf_obligation` may apply + // inference guidance that makes other goals go from ambig -> pass, for example. + // + // FIXME: We should probably just look into overflows here. + false, + ), + Ok((_, Certainty::Yes)) => { + bug!("did not expect successful goal when collecting ambiguity errors") + } + Err(_) => { + bug!("did not expect selection error when collecting ambiguity errors") + } + } + }); + + FulfillmentError { + obligation: if refine_obligation { + find_best_leaf_obligation(infcx, &root_obligation, true) + } else { + root_obligation.clone() + }, + code, + root_obligation, + } +} + +pub(super) fn fulfillment_error_for_overflow<'tcx>( + infcx: &InferCtxt<'tcx>, + root_obligation: PredicateObligation<'tcx>, +) -> FulfillmentError<'tcx> { + FulfillmentError { + obligation: find_best_leaf_obligation(infcx, &root_obligation, true), + code: FulfillmentErrorCode::Ambiguity { overflow: Some(true) }, + root_obligation, + } +} + +fn find_best_leaf_obligation<'tcx>( + infcx: &InferCtxt<'tcx>, + obligation: &PredicateObligation<'tcx>, + consider_ambiguities: bool, +) -> PredicateObligation<'tcx> { + let obligation = infcx.resolve_vars_if_possible(obligation.clone()); + // FIXME: we use a probe here as the `BestObligation` visitor does not + // check whether it uses candidates which get shadowed by where-bounds. + // + // We should probably fix the visitor to not do so instead, as this also + // means the leaf obligation may be incorrect. + infcx + .fudge_inference_if_ok(|| { + infcx + .visit_proof_tree(obligation.clone().into(), &mut BestObligation { + obligation: obligation.clone(), + consider_ambiguities, + }) + .break_value() + .ok_or(()) + }) + .unwrap_or(obligation) +} + +struct BestObligation<'tcx> { + obligation: PredicateObligation<'tcx>, + consider_ambiguities: bool, +} + +impl<'tcx> BestObligation<'tcx> { + fn with_derived_obligation( + &mut self, + derived_obligation: PredicateObligation<'tcx>, + and_then: impl FnOnce(&mut Self) -> <Self as ProofTreeVisitor<'tcx>>::Result, + ) -> <Self as ProofTreeVisitor<'tcx>>::Result { + let old_obligation = std::mem::replace(&mut self.obligation, derived_obligation); + let res = and_then(self); + self.obligation = old_obligation; + res + } + + /// Filter out the candidates that aren't interesting to visit for the + /// purposes of reporting errors. For ambiguities, we only consider + /// candidates that may hold. For errors, we only consider candidates that + /// *don't* hold and which have impl-where clauses that also don't hold. + fn non_trivial_candidates<'a>( + &self, + goal: &'a inspect::InspectGoal<'a, 'tcx>, + ) -> Vec<inspect::InspectCandidate<'a, 'tcx>> { + let mut candidates = goal.candidates(); + match self.consider_ambiguities { + true => { + // If we have an ambiguous obligation, we must consider *all* candidates + // that hold, or else we may guide inference causing other goals to go + // from ambig -> pass/fail. + candidates.retain(|candidate| candidate.result().is_ok()); + } + false => { + // If we have >1 candidate, one may still be due to "boring" reasons, like + // an alias-relate that failed to hold when deeply evaluated. We really + // don't care about reasons like this. + if candidates.len() > 1 { + candidates.retain(|candidate| { + goal.infcx().probe(|_| { + candidate.instantiate_nested_goals(self.span()).iter().any( + |nested_goal| { + matches!( + nested_goal.source(), + GoalSource::ImplWhereBound + | GoalSource::AliasBoundConstCondition + | GoalSource::InstantiateHigherRanked + | GoalSource::AliasWellFormed + ) && match (self.consider_ambiguities, nested_goal.result()) { + (true, Ok(Certainty::Maybe(MaybeCause::Ambiguity))) + | (false, Err(_)) => true, + _ => false, + } + }, + ) + }) + }); + } + + // Prefer a non-rigid candidate if there is one. + if candidates.len() > 1 { + candidates.retain(|candidate| { + !matches!(candidate.kind(), inspect::ProbeKind::RigidAlias { .. }) + }); + } + } + } + + candidates + } + + /// HACK: We walk the nested obligations for a well-formed arg manually, + /// since there's nontrivial logic in `wf.rs` to set up an obligation cause. + /// Ideally we'd be able to track this better. + fn visit_well_formed_goal( + &mut self, + candidate: &inspect::InspectCandidate<'_, 'tcx>, + arg: ty::GenericArg<'tcx>, + ) -> ControlFlow<PredicateObligation<'tcx>> { + let infcx = candidate.goal().infcx(); + let param_env = candidate.goal().goal().param_env; + let body_id = self.obligation.cause.body_id; + + for obligation in wf::unnormalized_obligations(infcx, param_env, arg, self.span(), body_id) + .into_iter() + .flatten() + { + let nested_goal = candidate.instantiate_proof_tree_for_nested_goal( + GoalSource::Misc, + Goal::new(infcx.tcx, obligation.param_env, obligation.predicate), + self.span(), + ); + // Skip nested goals that aren't the *reason* for our goal's failure. + match (self.consider_ambiguities, nested_goal.result()) { + (true, Ok(Certainty::Maybe(MaybeCause::Ambiguity))) | (false, Err(_)) => {} + _ => continue, + } + + self.with_derived_obligation(obligation, |this| nested_goal.visit_with(this))?; + } + + ControlFlow::Break(self.obligation.clone()) + } +} + +impl<'tcx> ProofTreeVisitor<'tcx> for BestObligation<'tcx> { + type Result = ControlFlow<PredicateObligation<'tcx>>; + + fn span(&self) -> rustc_span::Span { + self.obligation.cause.span + } + + #[instrument(level = "trace", skip(self, goal), fields(goal = ?goal.goal()))] + fn visit_goal(&mut self, goal: &inspect::InspectGoal<'_, 'tcx>) -> Self::Result { + let candidates = self.non_trivial_candidates(goal); + trace!(candidates = ?candidates.iter().map(|c| c.kind()).collect::<Vec<_>>()); + + let [candidate] = candidates.as_slice() else { + return ControlFlow::Break(self.obligation.clone()); + }; + + // Don't walk into impls that have `do_not_recommend`. + if let inspect::ProbeKind::TraitCandidate { + source: CandidateSource::Impl(impl_def_id), + result: _, + } = candidate.kind() + && goal.infcx().tcx.do_not_recommend_impl(impl_def_id) + { + return ControlFlow::Break(self.obligation.clone()); + } + + let tcx = goal.infcx().tcx; + // FIXME: Also, what about considering >1 layer up the stack? May be necessary + // for normalizes-to. + let pred_kind = goal.goal().predicate.kind(); + let child_mode = match pred_kind.skip_binder() { + ty::PredicateKind::Clause(ty::ClauseKind::Trait(pred)) => { + ChildMode::Trait(pred_kind.rebind(pred)) + } + ty::PredicateKind::Clause(ty::ClauseKind::HostEffect(pred)) => { + ChildMode::Host(pred_kind.rebind(pred)) + } + ty::PredicateKind::NormalizesTo(normalizes_to) + if matches!( + normalizes_to.alias.kind(tcx), + ty::AliasTermKind::ProjectionTy | ty::AliasTermKind::ProjectionConst + ) => + { + ChildMode::Trait(pred_kind.rebind(ty::TraitPredicate { + trait_ref: normalizes_to.alias.trait_ref(tcx), + polarity: ty::PredicatePolarity::Positive, + })) + } + ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(arg)) => { + return self.visit_well_formed_goal(candidate, arg); + } + _ => ChildMode::PassThrough, + }; + + let nested_goals = candidate.instantiate_nested_goals(self.span()); + + // If the candidate requires some `T: FnPtr` bound which does not hold should not be treated as + // an actual candidate, instead we should treat them as if the impl was never considered to + // have potentially applied. As if `impl<A, R> Trait for for<..> fn(..A) -> R` was written + // instead of `impl<T: FnPtr> Trait for T`. + // + // We do this as a separate loop so that we do not choose to tell the user about some nested + // goal before we encounter a `T: FnPtr` nested goal. + for nested_goal in &nested_goals { + if let Some(fn_ptr_trait) = tcx.lang_items().fn_ptr_trait() + && let Some(poly_trait_pred) = nested_goal.goal().predicate.as_trait_clause() + && poly_trait_pred.def_id() == fn_ptr_trait + && let Err(NoSolution) = nested_goal.result() + { + return ControlFlow::Break(self.obligation.clone()); + } + } + + let mut impl_where_bound_count = 0; + for nested_goal in nested_goals { + trace!(nested_goal = ?(nested_goal.goal(), nested_goal.source(), nested_goal.result())); + + let make_obligation = |cause| Obligation { + cause, + param_env: nested_goal.goal().param_env, + predicate: nested_goal.goal().predicate, + recursion_depth: self.obligation.recursion_depth + 1, + }; + + let obligation; + match (child_mode, nested_goal.source()) { + (ChildMode::Trait(_) | ChildMode::Host(_), GoalSource::Misc) => { + continue; + } + (ChildMode::Trait(parent_trait_pred), GoalSource::ImplWhereBound) => { + obligation = make_obligation(derive_cause( + tcx, + candidate.kind(), + self.obligation.cause.clone(), + impl_where_bound_count, + parent_trait_pred, + )); + impl_where_bound_count += 1; + } + ( + ChildMode::Host(parent_host_pred), + GoalSource::ImplWhereBound | GoalSource::AliasBoundConstCondition, + ) => { + obligation = make_obligation(derive_host_cause( + tcx, + candidate.kind(), + self.obligation.cause.clone(), + impl_where_bound_count, + parent_host_pred, + )); + impl_where_bound_count += 1; + } + // Skip over a higher-ranked predicate. + (_, GoalSource::InstantiateHigherRanked) => { + obligation = self.obligation.clone(); + } + (ChildMode::PassThrough, _) + | (_, GoalSource::AliasWellFormed | GoalSource::AliasBoundConstCondition) => { + obligation = make_obligation(self.obligation.cause.clone()); + } + } + + // Skip nested goals that aren't the *reason* for our goal's failure. + match (self.consider_ambiguities, nested_goal.result()) { + (true, Ok(Certainty::Maybe(MaybeCause::Ambiguity))) | (false, Err(_)) => {} + _ => continue, + } + + self.with_derived_obligation(obligation, |this| nested_goal.visit_with(this))?; + } + + // alias-relate may fail because the lhs or rhs can't be normalized, + // and therefore is treated as rigid. + if let Some(ty::PredicateKind::AliasRelate(lhs, rhs, _)) = pred_kind.no_bound_vars() { + if let Some(obligation) = goal + .infcx() + .visit_proof_tree_at_depth( + goal.goal().with(goal.infcx().tcx, ty::ClauseKind::WellFormed(lhs.into())), + goal.depth() + 1, + self, + ) + .break_value() + { + return ControlFlow::Break(obligation); + } else if let Some(obligation) = goal + .infcx() + .visit_proof_tree_at_depth( + goal.goal().with(goal.infcx().tcx, ty::ClauseKind::WellFormed(rhs.into())), + goal.depth() + 1, + self, + ) + .break_value() + { + return ControlFlow::Break(obligation); + } + } + + ControlFlow::Break(self.obligation.clone()) + } +} + +#[derive(Debug, Copy, Clone)] +enum ChildMode<'tcx> { + // Try to derive an `ObligationCause::{ImplDerived,BuiltinDerived}`, + // and skip all `GoalSource::Misc`, which represent useless obligations + // such as alias-eq which may not hold. + Trait(ty::PolyTraitPredicate<'tcx>), + // Try to derive an `ObligationCause::{ImplDerived,BuiltinDerived}`, + // and skip all `GoalSource::Misc`, which represent useless obligations + // such as alias-eq which may not hold. + Host(ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>), + // Skip trying to derive an `ObligationCause` from this obligation, and + // report *all* sub-obligations as if they came directly from the parent + // obligation. + PassThrough, +} + +fn derive_cause<'tcx>( + tcx: TyCtxt<'tcx>, + candidate_kind: inspect::ProbeKind<TyCtxt<'tcx>>, + mut cause: ObligationCause<'tcx>, + idx: usize, + parent_trait_pred: ty::PolyTraitPredicate<'tcx>, +) -> ObligationCause<'tcx> { + match candidate_kind { + inspect::ProbeKind::TraitCandidate { + source: CandidateSource::Impl(impl_def_id), + result: _, + } => { + if let Some((_, span)) = + tcx.predicates_of(impl_def_id).instantiate_identity(tcx).iter().nth(idx) + { + cause = cause.derived_cause(parent_trait_pred, |derived| { + ObligationCauseCode::ImplDerived(Box::new(traits::ImplDerivedCause { + derived, + impl_or_alias_def_id: impl_def_id, + impl_def_predicate_index: Some(idx), + span, + })) + }) + } + } + inspect::ProbeKind::TraitCandidate { + source: CandidateSource::BuiltinImpl(..), + result: _, + } => { + cause = cause.derived_cause(parent_trait_pred, ObligationCauseCode::BuiltinDerived); + } + _ => {} + }; + cause +} + +fn derive_host_cause<'tcx>( + tcx: TyCtxt<'tcx>, + candidate_kind: inspect::ProbeKind<TyCtxt<'tcx>>, + mut cause: ObligationCause<'tcx>, + idx: usize, + parent_host_pred: ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>, +) -> ObligationCause<'tcx> { + match candidate_kind { + inspect::ProbeKind::TraitCandidate { + source: CandidateSource::Impl(impl_def_id), + result: _, + } => { + if let Some((_, span)) = tcx + .predicates_of(impl_def_id) + .instantiate_identity(tcx) + .into_iter() + .chain(tcx.const_conditions(impl_def_id).instantiate_identity(tcx).into_iter().map( + |(trait_ref, span)| { + ( + trait_ref.to_host_effect_clause( + tcx, + parent_host_pred.skip_binder().constness, + ), + span, + ) + }, + )) + .nth(idx) + { + cause = + cause.derived_host_cause(parent_host_pred, |derived| { + ObligationCauseCode::ImplDerivedHost(Box::new( + traits::ImplDerivedHostCause { derived, impl_def_id, span }, + )) + }) + } + } + inspect::ProbeKind::TraitCandidate { + source: CandidateSource::BuiltinImpl(..), + result: _, + } => { + cause = + cause.derived_host_cause(parent_host_pred, ObligationCauseCode::BuiltinDerivedHost); + } + _ => {} + }; + cause +} diff --git a/compiler/rustc_trait_selection/src/solve/inspect/analyse.rs b/compiler/rustc_trait_selection/src/solve/inspect/analyse.rs index e735020a63e..9ba48cd588f 100644 --- a/compiler/rustc_trait_selection/src/solve/inspect/analyse.rs +++ b/compiler/rustc_trait_selection/src/solve/inspect/analyse.rs @@ -194,47 +194,57 @@ impl<'a, 'tcx> InspectCandidate<'a, 'tcx> { let goals = instantiated_goals .into_iter() - .map(|(source, goal)| match goal.predicate.kind().no_bound_vars() { - Some(ty::PredicateKind::NormalizesTo(ty::NormalizesTo { alias, term })) => { - let unconstrained_term = match term.unpack() { - ty::TermKind::Ty(_) => infcx.next_ty_var(span).into(), - ty::TermKind::Const(_) => infcx.next_const_var(span).into(), - }; - let goal = - goal.with(infcx.tcx, ty::NormalizesTo { alias, term: unconstrained_term }); - // We have to use a `probe` here as evaluating a `NormalizesTo` can constrain the - // expected term. This means that candidates which only fail due to nested goals - // and which normalize to a different term then the final result could ICE: when - // building their proof tree, the expected term was unconstrained, but when - // instantiating the candidate it is already constrained to the result of another - // candidate. - let proof_tree = infcx - .probe(|_| infcx.evaluate_root_goal_raw(goal, GenerateProofTree::Yes).1); - InspectGoal::new( - infcx, - self.goal.depth + 1, - proof_tree.unwrap(), - Some(NormalizesToTermHack { term, unconstrained_term }), - source, - ) - } - _ => { - // We're using a probe here as evaluating a goal could constrain - // inference variables by choosing one candidate. If we then recurse - // into another candidate who ends up with different inference - // constraints, we get an ICE if we already applied the constraints - // from the chosen candidate. - let proof_tree = infcx - .probe(|_| infcx.evaluate_root_goal(goal, GenerateProofTree::Yes).1) - .unwrap(); - InspectGoal::new(infcx, self.goal.depth + 1, proof_tree, None, source) - } - }) + .map(|(source, goal)| self.instantiate_proof_tree_for_nested_goal(source, goal, span)) .collect(); (goals, opt_impl_args) } + pub fn instantiate_proof_tree_for_nested_goal( + &self, + source: GoalSource, + goal: Goal<'tcx, ty::Predicate<'tcx>>, + span: Span, + ) -> InspectGoal<'a, 'tcx> { + let infcx = self.goal.infcx; + match goal.predicate.kind().no_bound_vars() { + Some(ty::PredicateKind::NormalizesTo(ty::NormalizesTo { alias, term })) => { + let unconstrained_term = match term.unpack() { + ty::TermKind::Ty(_) => infcx.next_ty_var(span).into(), + ty::TermKind::Const(_) => infcx.next_const_var(span).into(), + }; + let goal = + goal.with(infcx.tcx, ty::NormalizesTo { alias, term: unconstrained_term }); + // We have to use a `probe` here as evaluating a `NormalizesTo` can constrain the + // expected term. This means that candidates which only fail due to nested goals + // and which normalize to a different term then the final result could ICE: when + // building their proof tree, the expected term was unconstrained, but when + // instantiating the candidate it is already constrained to the result of another + // candidate. + let proof_tree = + infcx.probe(|_| infcx.evaluate_root_goal_raw(goal, GenerateProofTree::Yes).1); + InspectGoal::new( + infcx, + self.goal.depth + 1, + proof_tree.unwrap(), + Some(NormalizesToTermHack { term, unconstrained_term }), + source, + ) + } + _ => { + // We're using a probe here as evaluating a goal could constrain + // inference variables by choosing one candidate. If we then recurse + // into another candidate who ends up with different inference + // constraints, we get an ICE if we already applied the constraints + // from the chosen candidate. + let proof_tree = infcx + .probe(|_| infcx.evaluate_root_goal(goal, GenerateProofTree::Yes).1) + .unwrap(); + InspectGoal::new(infcx, self.goal.depth + 1, proof_tree, None, source) + } + } + } + /// Visit all nested goals of this candidate, rolling back /// all inference constraints. pub fn visit_nested_in_probe<V: ProofTreeVisitor<'tcx>>(&self, visitor: &mut V) -> V::Result { diff --git a/compiler/rustc_trait_selection/src/traits/mod.rs b/compiler/rustc_trait_selection/src/traits/mod.rs index 6b5ebade6ae..d4a9664e282 100644 --- a/compiler/rustc_trait_selection/src/traits/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/mod.rs @@ -76,6 +76,7 @@ use crate::infer::{InferCtxt, TyCtxtInferExt}; use crate::regions::InferCtxtRegionExt; use crate::traits::query::evaluate_obligation::InferCtxtExt as _; +#[derive(Debug)] pub struct FulfillmentError<'tcx> { pub obligation: PredicateObligation<'tcx>, pub code: FulfillmentErrorCode<'tcx>, @@ -107,12 +108,6 @@ impl<'tcx> FulfillmentError<'tcx> { } } -impl<'tcx> Debug for FulfillmentError<'tcx> { - fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { - write!(f, "FulfillmentError({:?},{:?})", self.obligation, self.code) - } -} - #[derive(Clone)] pub enum FulfillmentErrorCode<'tcx> { /// Inherently impossible to fulfill; this trait is implemented if and only diff --git a/compiler/rustc_trait_selection/src/traits/query/type_op/implied_outlives_bounds.rs b/compiler/rustc_trait_selection/src/traits/query/type_op/implied_outlives_bounds.rs index 1339739ce7f..ec0b7903396 100644 --- a/compiler/rustc_trait_selection/src/traits/query/type_op/implied_outlives_bounds.rs +++ b/compiler/rustc_trait_selection/src/traits/query/type_op/implied_outlives_bounds.rs @@ -5,8 +5,8 @@ use rustc_infer::traits::query::type_op::ImpliedOutlivesBounds; use rustc_middle::infer::canonical::CanonicalQueryResponse; use rustc_middle::traits::ObligationCause; use rustc_middle::ty::{self, ParamEnvAnd, Ty, TyCtxt, TypeFolder, TypeVisitableExt}; -use rustc_span::Span; use rustc_span::def_id::CRATE_DEF_ID; +use rustc_span::{DUMMY_SP, Span}; use rustc_type_ir::outlives::{Component, push_outlives_components}; use smallvec::{SmallVec, smallvec}; use tracing::debug; @@ -92,7 +92,9 @@ pub fn compute_implied_outlives_bounds_inner<'tcx>( // From the full set of obligations, just filter down to the region relationships. for obligation in - wf::unnormalized_obligations(ocx.infcx, param_env, arg).into_iter().flatten() + wf::unnormalized_obligations(ocx.infcx, param_env, arg, DUMMY_SP, CRATE_DEF_ID) + .into_iter() + .flatten() { assert!(!obligation.has_escaping_bound_vars()); let Some(pred) = obligation.predicate.kind().no_bound_vars() else { diff --git a/compiler/rustc_trait_selection/src/traits/wf.rs b/compiler/rustc_trait_selection/src/traits/wf.rs index 20b675bcb76..96051ad0aa5 100644 --- a/compiler/rustc_trait_selection/src/traits/wf.rs +++ b/compiler/rustc_trait_selection/src/traits/wf.rs @@ -8,8 +8,8 @@ use rustc_middle::ty::{ self, GenericArg, GenericArgKind, GenericArgsRef, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor, }; -use rustc_span::def_id::{CRATE_DEF_ID, DefId, LocalDefId}; -use rustc_span::{DUMMY_SP, Span}; +use rustc_span::Span; +use rustc_span::def_id::{DefId, LocalDefId}; use tracing::{debug, instrument, trace}; use crate::infer::InferCtxt; @@ -89,6 +89,8 @@ pub fn unnormalized_obligations<'tcx>( infcx: &InferCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>, arg: GenericArg<'tcx>, + span: Span, + body_id: LocalDefId, ) -> Option<PredicateObligations<'tcx>> { debug_assert_eq!(arg, infcx.resolve_vars_if_possible(arg)); @@ -106,8 +108,8 @@ pub fn unnormalized_obligations<'tcx>( let mut wf = WfPredicates { infcx, param_env, - body_id: CRATE_DEF_ID, - span: DUMMY_SP, + body_id, + span, out: PredicateObligations::new(), recursion_depth: 0, item: None, @@ -828,8 +830,25 @@ impl<'a, 'tcx> TypeVisitor<TyCtxt<'tcx>> for WfPredicates<'a, 'tcx> { // Let the visitor iterate into the argument/return // types appearing in the fn signature. } - ty::UnsafeBinder(_) => { - // FIXME(unsafe_binders): We should also recurse into the binder here. + ty::UnsafeBinder(ty) => { + // FIXME(unsafe_binders): For now, we have no way to express + // that a type must be `ManuallyDrop` OR `Copy` (or a pointer). + if !ty.has_escaping_bound_vars() { + self.out.push(traits::Obligation::new( + self.tcx(), + self.cause(ObligationCauseCode::Misc), + self.param_env, + ty.map_bound(|ty| { + ty::TraitRef::new( + self.tcx(), + self.tcx().require_lang_item(LangItem::Copy, Some(self.span)), + [ty], + ) + }), + )); + } + + // We recurse into the binder below. } ty::Dynamic(data, r, _) => { diff --git a/compiler/rustc_ty_utils/src/consts.rs b/compiler/rustc_ty_utils/src/consts.rs index 931c36137ee..4038a1d68fa 100644 --- a/compiler/rustc_ty_utils/src/consts.rs +++ b/compiler/rustc_ty_utils/src/consts.rs @@ -116,6 +116,11 @@ fn recurse_build<'tcx>( | &ExprKind::ValueTypeAscription { source, .. } => { recurse_build(tcx, body, source, root_span)? } + &ExprKind::PlaceUnwrapUnsafeBinder { .. } + | &ExprKind::ValueUnwrapUnsafeBinder { .. } + | &ExprKind::WrapUnsafeBinder { .. } => { + todo!("FIXME(unsafe_binders)") + } &ExprKind::Literal { lit, neg } => { let sp = node.span; tcx.at(sp).lit_to_const(LitToConstInput { lit: &lit.node, ty: node.ty, neg }) @@ -347,6 +352,9 @@ impl<'a, 'tcx> IsThirPolymorphic<'a, 'tcx> { | thir::ExprKind::Adt(_) | thir::ExprKind::PlaceTypeAscription { .. } | thir::ExprKind::ValueTypeAscription { .. } + | thir::ExprKind::PlaceUnwrapUnsafeBinder { .. } + | thir::ExprKind::ValueUnwrapUnsafeBinder { .. } + | thir::ExprKind::WrapUnsafeBinder { .. } | thir::ExprKind::Closure(_) | thir::ExprKind::Literal { .. } | thir::ExprKind::NonHirLiteral { .. } diff --git a/library/core/src/cmp.rs b/library/core/src/cmp.rs index 97974d195fe..594236cf1d9 100644 --- a/library/core/src/cmp.rs +++ b/library/core/src/cmp.rs @@ -973,6 +973,24 @@ pub trait Ord: Eq + PartialOrd<Self> { /// assert_eq!(1.max(2), 2); /// assert_eq!(2.max(2), 2); /// ``` + /// ``` + /// use std::cmp::Ordering; + /// + /// #[derive(Eq)] + /// struct Equal(&'static str); + /// + /// impl PartialEq for Equal { + /// fn eq(&self, other: &Self) -> bool { true } + /// } + /// impl PartialOrd for Equal { + /// fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(Ordering::Equal) } + /// } + /// impl Ord for Equal { + /// fn cmp(&self, other: &Self) -> Ordering { Ordering::Equal } + /// } + /// + /// assert_eq!(Equal("self").max(Equal("other")).0, "other"); + /// ``` #[stable(feature = "ord_max_min", since = "1.21.0")] #[inline] #[must_use] @@ -981,7 +999,7 @@ pub trait Ord: Eq + PartialOrd<Self> { where Self: Sized, { - max_by(self, other, Ord::cmp) + if other < self { self } else { other } } /// Compares and returns the minimum of two values. @@ -994,6 +1012,24 @@ pub trait Ord: Eq + PartialOrd<Self> { /// assert_eq!(1.min(2), 1); /// assert_eq!(2.min(2), 2); /// ``` + /// ``` + /// use std::cmp::Ordering; + /// + /// #[derive(Eq)] + /// struct Equal(&'static str); + /// + /// impl PartialEq for Equal { + /// fn eq(&self, other: &Self) -> bool { true } + /// } + /// impl PartialOrd for Equal { + /// fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(Ordering::Equal) } + /// } + /// impl Ord for Equal { + /// fn cmp(&self, other: &Self) -> Ordering { Ordering::Equal } + /// } + /// + /// assert_eq!(Equal("self").min(Equal("other")).0, "self"); + /// ``` #[stable(feature = "ord_max_min", since = "1.21.0")] #[inline] #[must_use] @@ -1002,7 +1038,7 @@ pub trait Ord: Eq + PartialOrd<Self> { where Self: Sized, { - min_by(self, other, Ord::cmp) + if other < self { other } else { self } } /// Restrict a value to a certain interval. @@ -1414,6 +1450,24 @@ pub macro PartialOrd($item:item) { /// assert_eq!(cmp::min(1, 2), 1); /// assert_eq!(cmp::min(2, 2), 2); /// ``` +/// ``` +/// use std::cmp::{self, Ordering}; +/// +/// #[derive(Eq)] +/// struct Equal(&'static str); +/// +/// impl PartialEq for Equal { +/// fn eq(&self, other: &Self) -> bool { true } +/// } +/// impl PartialOrd for Equal { +/// fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(Ordering::Equal) } +/// } +/// impl Ord for Equal { +/// fn cmp(&self, other: &Self) -> Ordering { Ordering::Equal } +/// } +/// +/// assert_eq!(cmp::min(Equal("v1"), Equal("v2")).0, "v1"); +/// ``` #[inline] #[must_use] #[stable(feature = "rust1", since = "1.0.0")] @@ -1431,20 +1485,22 @@ pub fn min<T: Ord>(v1: T, v2: T) -> T { /// ``` /// use std::cmp; /// -/// let result = cmp::min_by(-2, 1, |x: &i32, y: &i32| x.abs().cmp(&y.abs())); -/// assert_eq!(result, 1); +/// let abs_cmp = |x: &i32, y: &i32| x.abs().cmp(&y.abs()); /// -/// let result = cmp::min_by(-2, 3, |x: &i32, y: &i32| x.abs().cmp(&y.abs())); -/// assert_eq!(result, -2); +/// let result = cmp::min_by(2, -1, abs_cmp); +/// assert_eq!(result, -1); +/// +/// let result = cmp::min_by(2, -3, abs_cmp); +/// assert_eq!(result, 2); +/// +/// let result = cmp::min_by(1, -1, abs_cmp); +/// assert_eq!(result, 1); /// ``` #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] pub fn min_by<T, F: FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T { - match compare(&v1, &v2) { - Ordering::Less | Ordering::Equal => v1, - Ordering::Greater => v2, - } + if compare(&v2, &v1).is_lt() { v2 } else { v1 } } /// Returns the element that gives the minimum value from the specified function. @@ -1456,17 +1512,20 @@ pub fn min_by<T, F: FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T { /// ``` /// use std::cmp; /// -/// let result = cmp::min_by_key(-2, 1, |x: &i32| x.abs()); -/// assert_eq!(result, 1); +/// let result = cmp::min_by_key(2, -1, |x: &i32| x.abs()); +/// assert_eq!(result, -1); /// -/// let result = cmp::min_by_key(-2, 2, |x: &i32| x.abs()); -/// assert_eq!(result, -2); +/// let result = cmp::min_by_key(2, -3, |x: &i32| x.abs()); +/// assert_eq!(result, 2); +/// +/// let result = cmp::min_by_key(1, -1, |x: &i32| x.abs()); +/// assert_eq!(result, 1); /// ``` #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] pub fn min_by_key<T, F: FnMut(&T) -> K, K: Ord>(v1: T, v2: T, mut f: F) -> T { - min_by(v1, v2, |v1, v2| f(v1).cmp(&f(v2))) + if f(&v2) < f(&v1) { v2 } else { v1 } } /// Compares and returns the maximum of two values. @@ -1483,6 +1542,24 @@ pub fn min_by_key<T, F: FnMut(&T) -> K, K: Ord>(v1: T, v2: T, mut f: F) -> T { /// assert_eq!(cmp::max(1, 2), 2); /// assert_eq!(cmp::max(2, 2), 2); /// ``` +/// ``` +/// use std::cmp::{self, Ordering}; +/// +/// #[derive(Eq)] +/// struct Equal(&'static str); +/// +/// impl PartialEq for Equal { +/// fn eq(&self, other: &Self) -> bool { true } +/// } +/// impl PartialOrd for Equal { +/// fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(Ordering::Equal) } +/// } +/// impl Ord for Equal { +/// fn cmp(&self, other: &Self) -> Ordering { Ordering::Equal } +/// } +/// +/// assert_eq!(cmp::max(Equal("v1"), Equal("v2")).0, "v2"); +/// ``` #[inline] #[must_use] #[stable(feature = "rust1", since = "1.0.0")] @@ -1500,20 +1577,22 @@ pub fn max<T: Ord>(v1: T, v2: T) -> T { /// ``` /// use std::cmp; /// -/// let result = cmp::max_by(-2, 1, |x: &i32, y: &i32| x.abs().cmp(&y.abs())); +/// let abs_cmp = |x: &i32, y: &i32| x.abs().cmp(&y.abs()); +/// +/// let result = cmp::max_by(3, -2, abs_cmp) ; +/// assert_eq!(result, 3); +/// +/// let result = cmp::max_by(1, -2, abs_cmp); /// assert_eq!(result, -2); /// -/// let result = cmp::max_by(-2, 2, |x: &i32, y: &i32| x.abs().cmp(&y.abs())) ; -/// assert_eq!(result, 2); +/// let result = cmp::max_by(1, -1, abs_cmp); +/// assert_eq!(result, -1); /// ``` #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] pub fn max_by<T, F: FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T { - match compare(&v1, &v2) { - Ordering::Less | Ordering::Equal => v2, - Ordering::Greater => v1, - } + if compare(&v2, &v1).is_lt() { v1 } else { v2 } } /// Returns the element that gives the maximum value from the specified function. @@ -1525,17 +1604,20 @@ pub fn max_by<T, F: FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T { /// ``` /// use std::cmp; /// -/// let result = cmp::max_by_key(-2, 1, |x: &i32| x.abs()); +/// let result = cmp::max_by_key(3, -2, |x: &i32| x.abs()); +/// assert_eq!(result, 3); +/// +/// let result = cmp::max_by_key(1, -2, |x: &i32| x.abs()); /// assert_eq!(result, -2); /// -/// let result = cmp::max_by_key(-2, 2, |x: &i32| x.abs()); -/// assert_eq!(result, 2); +/// let result = cmp::max_by_key(1, -1, |x: &i32| x.abs()); +/// assert_eq!(result, -1); /// ``` #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] pub fn max_by_key<T, F: FnMut(&T) -> K, K: Ord>(v1: T, v2: T, mut f: F) -> T { - max_by(v1, v2, |v1, v2| f(v1).cmp(&f(v2))) + if f(&v2) < f(&v1) { v1 } else { v2 } } /// Compares and sorts two values, returning minimum and maximum. @@ -1549,13 +1631,32 @@ pub fn max_by_key<T, F: FnMut(&T) -> K, K: Ord>(v1: T, v2: T, mut f: F) -> T { /// use std::cmp; /// /// assert_eq!(cmp::minmax(1, 2), [1, 2]); -/// assert_eq!(cmp::minmax(2, 2), [2, 2]); +/// assert_eq!(cmp::minmax(2, 1), [1, 2]); /// /// // You can destructure the result using array patterns /// let [min, max] = cmp::minmax(42, 17); /// assert_eq!(min, 17); /// assert_eq!(max, 42); /// ``` +/// ``` +/// #![feature(cmp_minmax)] +/// use std::cmp::{self, Ordering}; +/// +/// #[derive(Eq)] +/// struct Equal(&'static str); +/// +/// impl PartialEq for Equal { +/// fn eq(&self, other: &Self) -> bool { true } +/// } +/// impl PartialOrd for Equal { +/// fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(Ordering::Equal) } +/// } +/// impl Ord for Equal { +/// fn cmp(&self, other: &Self) -> Ordering { Ordering::Equal } +/// } +/// +/// assert_eq!(cmp::minmax(Equal("v1"), Equal("v2")).map(|v| v.0), ["v1", "v2"]); +/// ``` #[inline] #[must_use] #[unstable(feature = "cmp_minmax", issue = "115939")] @@ -1563,7 +1664,7 @@ pub fn minmax<T>(v1: T, v2: T) -> [T; 2] where T: Ord, { - if v1 <= v2 { [v1, v2] } else { [v2, v1] } + if v2 < v1 { [v2, v1] } else { [v1, v2] } } /// Returns minimum and maximum values with respect to the specified comparison function. @@ -1576,11 +1677,14 @@ where /// #![feature(cmp_minmax)] /// use std::cmp; /// -/// assert_eq!(cmp::minmax_by(-2, 1, |x: &i32, y: &i32| x.abs().cmp(&y.abs())), [1, -2]); -/// assert_eq!(cmp::minmax_by(-2, 2, |x: &i32, y: &i32| x.abs().cmp(&y.abs())), [-2, 2]); +/// let abs_cmp = |x: &i32, y: &i32| x.abs().cmp(&y.abs()); +/// +/// assert_eq!(cmp::minmax_by(-2, 1, abs_cmp), [1, -2]); +/// assert_eq!(cmp::minmax_by(-1, 2, abs_cmp), [-1, 2]); +/// assert_eq!(cmp::minmax_by(-2, 2, abs_cmp), [-2, 2]); /// /// // You can destructure the result using array patterns -/// let [min, max] = cmp::minmax_by(-42, 17, |x: &i32, y: &i32| x.abs().cmp(&y.abs())); +/// let [min, max] = cmp::minmax_by(-42, 17, abs_cmp); /// assert_eq!(min, 17); /// assert_eq!(max, -42); /// ``` @@ -1591,7 +1695,7 @@ pub fn minmax_by<T, F>(v1: T, v2: T, compare: F) -> [T; 2] where F: FnOnce(&T, &T) -> Ordering, { - if compare(&v1, &v2).is_le() { [v1, v2] } else { [v2, v1] } + if compare(&v2, &v1).is_lt() { [v2, v1] } else { [v1, v2] } } /// Returns minimum and maximum values with respect to the specified key function. @@ -1620,7 +1724,7 @@ where F: FnMut(&T) -> K, K: Ord, { - minmax_by(v1, v2, |v1, v2| f(v1).cmp(&f(v2))) + if f(&v2) < f(&v1) { [v2, v1] } else { [v1, v2] } } // Implementation of PartialEq, Eq, PartialOrd and Ord for primitive types diff --git a/library/core/src/marker.rs b/library/core/src/marker.rs index a793fc2aa2e..18ada14d101 100644 --- a/library/core/src/marker.rs +++ b/library/core/src/marker.rs @@ -1091,7 +1091,195 @@ pub trait FnPtr: Copy + Clone { fn addr(self) -> *const (); } -/// Derive macro generating impls of traits related to smart pointers. +/// Derive macro that makes a smart pointer usable with trait objects. +/// +/// # What this macro does +/// +/// This macro is intended to be used with user-defined pointer types, and makes it possible to +/// perform coercions on the pointee of the user-defined pointer. There are two aspects to this: +/// +/// ## Unsizing coercions of the pointee +/// +/// By using the macro, the following example will compile: +/// ``` +/// #![feature(derive_coerce_pointee)] +/// use std::marker::CoercePointee; +/// use std::ops::Deref; +/// +/// #[derive(CoercePointee)] +/// #[repr(transparent)] +/// struct MySmartPointer<T: ?Sized>(Box<T>); +/// +/// impl<T: ?Sized> Deref for MySmartPointer<T> { +/// type Target = T; +/// fn deref(&self) -> &T { +/// &self.0 +/// } +/// } +/// +/// trait MyTrait {} +/// +/// impl MyTrait for i32 {} +/// +/// fn main() { +/// let ptr: MySmartPointer<i32> = MySmartPointer(Box::new(4)); +/// +/// // This coercion would be an error without the derive. +/// let ptr: MySmartPointer<dyn MyTrait> = ptr; +/// } +/// ``` +/// Without the `#[derive(CoercePointee)]` macro, this example would fail with the following error: +/// ```text +/// error[E0308]: mismatched types +/// --> src/main.rs:11:44 +/// | +/// 11 | let ptr: MySmartPointer<dyn MyTrait> = ptr; +/// | --------------------------- ^^^ expected `MySmartPointer<dyn MyTrait>`, found `MySmartPointer<i32>` +/// | | +/// | expected due to this +/// | +/// = note: expected struct `MySmartPointer<dyn MyTrait>` +/// found struct `MySmartPointer<i32>` +/// = help: `i32` implements `MyTrait` so you could box the found value and coerce it to the trait object `Box<dyn MyTrait>`, you will have to change the expected type as well +/// ``` +/// +/// ## Dyn compatibility +/// +/// This macro allows you to dispatch on the user-defined pointer type. That is, traits using the +/// type as a receiver are dyn-compatible. For example, this compiles: +/// +/// ``` +/// #![feature(arbitrary_self_types, derive_coerce_pointee)] +/// use std::marker::CoercePointee; +/// use std::ops::Deref; +/// +/// #[derive(CoercePointee)] +/// #[repr(transparent)] +/// struct MySmartPointer<T: ?Sized>(Box<T>); +/// +/// impl<T: ?Sized> Deref for MySmartPointer<T> { +/// type Target = T; +/// fn deref(&self) -> &T { +/// &self.0 +/// } +/// } +/// +/// // You can always define this trait. (as long as you have #![feature(arbitrary_self_types)]) +/// trait MyTrait { +/// fn func(self: MySmartPointer<Self>); +/// } +/// +/// // But using `dyn MyTrait` requires #[derive(CoercePointee)]. +/// fn call_func(value: MySmartPointer<dyn MyTrait>) { +/// value.func(); +/// } +/// ``` +/// If you remove the `#[derive(CoercePointee)]` annotation from the struct, then the above example +/// will fail with this error message: +/// ```text +/// error[E0038]: the trait `MyTrait` is not dyn compatible +/// --> src/lib.rs:21:36 +/// | +/// 17 | fn func(self: MySmartPointer<Self>); +/// | -------------------- help: consider changing method `func`'s `self` parameter to be `&self`: `&Self` +/// ... +/// 21 | fn call_func(value: MySmartPointer<dyn MyTrait>) { +/// | ^^^^^^^^^^^ `MyTrait` is not dyn compatible +/// | +/// note: for a trait to be dyn compatible it needs to allow building a vtable +/// for more information, visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety> +/// --> src/lib.rs:17:19 +/// | +/// 16 | trait MyTrait { +/// | ------- this trait is not dyn compatible... +/// 17 | fn func(self: MySmartPointer<Self>); +/// | ^^^^^^^^^^^^^^^^^^^^ ...because method `func`'s `self` parameter cannot be dispatched on +/// ``` +/// +/// # Requirements for using the macro +/// +/// This macro can only be used if: +/// * The type is a `#[repr(transparent)]` struct. +/// * The type of its non-zero-sized field must either be a standard library pointer type +/// (reference, raw pointer, `NonNull`, `Box`, `Rc`, `Arc`, etc.) or another user-defined type +/// also using the `#[derive(CoercePointee)]` macro. +/// * Zero-sized fields must not mention any generic parameters unless the zero-sized field has +/// type [`PhantomData`]. +/// +/// ## Multiple type parameters +/// +/// If the type has multiple type parameters, then you must explicitly specify which one should be +/// used for dynamic dispatch. For example: +/// ``` +/// # #![feature(derive_coerce_pointee)] +/// # use std::marker::{CoercePointee, PhantomData}; +/// #[derive(CoercePointee)] +/// #[repr(transparent)] +/// struct MySmartPointer<#[pointee] T: ?Sized, U> { +/// ptr: Box<T>, +/// _phantom: PhantomData<U>, +/// } +/// ``` +/// Specifying `#[pointee]` when the struct has only one type parameter is allowed, but not required. +/// +/// # Examples +/// +/// A custom implementation of the `Rc` type: +/// ``` +/// #![feature(derive_coerce_pointee)] +/// use std::marker::CoercePointee; +/// use std::ops::Deref; +/// use std::ptr::NonNull; +/// +/// #[derive(CoercePointee)] +/// #[repr(transparent)] +/// pub struct Rc<T: ?Sized> { +/// inner: NonNull<RcInner<T>>, +/// } +/// +/// struct RcInner<T: ?Sized> { +/// refcount: usize, +/// value: T, +/// } +/// +/// impl<T: ?Sized> Deref for Rc<T> { +/// type Target = T; +/// fn deref(&self) -> &T { +/// let ptr = self.inner.as_ptr(); +/// unsafe { &(*ptr).value } +/// } +/// } +/// +/// impl<T> Rc<T> { +/// pub fn new(value: T) -> Self { +/// let inner = Box::new(RcInner { +/// refcount: 1, +/// value, +/// }); +/// Self { +/// inner: NonNull::from(Box::leak(inner)), +/// } +/// } +/// } +/// +/// impl<T: ?Sized> Clone for Rc<T> { +/// fn clone(&self) -> Self { +/// // A real implementation would handle overflow here. +/// unsafe { (*self.inner.as_ptr()).refcount += 1 }; +/// Self { inner: self.inner } +/// } +/// } +/// +/// impl<T: ?Sized> Drop for Rc<T> { +/// fn drop(&mut self) { +/// let ptr = self.inner.as_ptr(); +/// unsafe { (*ptr).refcount -= 1 }; +/// if unsafe { (*ptr).refcount } == 0 { +/// drop(unsafe { Box::from_raw(ptr) }); +/// } +/// } +/// } +/// ``` #[rustc_builtin_macro(CoercePointee, attributes(pointee))] #[allow_internal_unstable(dispatch_from_dyn, coerce_unsized, unsize)] #[unstable(feature = "derive_coerce_pointee", issue = "123430")] diff --git a/library/core/src/ptr/const_ptr.rs b/library/core/src/ptr/const_ptr.rs index ec569291853..0c6eaf60d04 100644 --- a/library/core/src/ptr/const_ptr.rs +++ b/library/core/src/ptr/const_ptr.rs @@ -1681,7 +1681,7 @@ impl<T, const N: usize> *const [T; N] { } } -// Equality for pointers +/// Pointer equality is by address, as produced by the [`<*const T>::addr`](pointer::addr) method. #[stable(feature = "rust1", since = "1.0.0")] impl<T: ?Sized> PartialEq for *const T { #[inline] @@ -1691,10 +1691,11 @@ impl<T: ?Sized> PartialEq for *const T { } } +/// Pointer equality is an equivalence relation. #[stable(feature = "rust1", since = "1.0.0")] impl<T: ?Sized> Eq for *const T {} -// Comparison for pointers +/// Pointer comparison is by address, as produced by the `[`<*const T>::addr`](pointer::addr)` method. #[stable(feature = "rust1", since = "1.0.0")] impl<T: ?Sized> Ord for *const T { #[inline] @@ -1710,6 +1711,7 @@ impl<T: ?Sized> Ord for *const T { } } +/// Pointer comparison is by address, as produced by the `[`<*const T>::addr`](pointer::addr)` method. #[stable(feature = "rust1", since = "1.0.0")] impl<T: ?Sized> PartialOrd for *const T { #[inline] diff --git a/library/core/src/ptr/mut_ptr.rs b/library/core/src/ptr/mut_ptr.rs index 5d9d337f101..d1b0104c0fa 100644 --- a/library/core/src/ptr/mut_ptr.rs +++ b/library/core/src/ptr/mut_ptr.rs @@ -2097,7 +2097,7 @@ impl<T, const N: usize> *mut [T; N] { } } -// Equality for pointers +/// Pointer equality is by address, as produced by the [`<*mut T>::addr`](pointer::addr) method. #[stable(feature = "rust1", since = "1.0.0")] impl<T: ?Sized> PartialEq for *mut T { #[inline(always)] @@ -2107,9 +2107,11 @@ impl<T: ?Sized> PartialEq for *mut T { } } +/// Pointer equality is an equivalence relation. #[stable(feature = "rust1", since = "1.0.0")] impl<T: ?Sized> Eq for *mut T {} +/// Pointer comparison is by address, as produced by the [`<*mut T>::addr`](pointer::addr) method. #[stable(feature = "rust1", since = "1.0.0")] impl<T: ?Sized> Ord for *mut T { #[inline] @@ -2125,6 +2127,7 @@ impl<T: ?Sized> Ord for *mut T { } } +/// Pointer comparison is by address, as produced by the [`<*mut T>::addr`](pointer::addr) method. #[stable(feature = "rust1", since = "1.0.0")] impl<T: ?Sized> PartialOrd for *mut T { #[inline(always)] diff --git a/library/core/src/slice/sort/stable/drift.rs b/library/core/src/slice/sort/stable/drift.rs index 644e75a4581..cf1df1e91a5 100644 --- a/library/core/src/slice/sort/stable/drift.rs +++ b/library/core/src/slice/sort/stable/drift.rs @@ -10,8 +10,8 @@ use crate::{cmp, intrinsics}; /// Sorts `v` based on comparison function `is_less`. If `eager_sort` is true, /// it will only do small-sorts and physical merges, ensuring O(N * log(N)) -/// worst-case complexity. `scratch.len()` must be at least `max(v.len() / 2, -/// MIN_SMALL_SORT_SCRATCH_LEN)` otherwise the implementation may abort. +/// worst-case complexity. `scratch.len()` must be at least +/// `max(v.len() - v.len() / 2, SMALL_SORT_GENERAL_SCRATCH_LEN)` otherwise the implementation may abort. /// Fully ascending and descending inputs will be sorted with exactly N - 1 /// comparisons. /// diff --git a/library/core/src/slice/sort/stable/mod.rs b/library/core/src/slice/sort/stable/mod.rs index 7adcc83b818..3ff2e71fd05 100644 --- a/library/core/src/slice/sort/stable/mod.rs +++ b/library/core/src/slice/sort/stable/mod.rs @@ -41,6 +41,8 @@ pub fn sort<T, F: FnMut(&T, &T) -> bool, BufT: BufGuard<T>>(v: &mut [T], is_less cfg_if! { if #[cfg(any(feature = "optimize_for_size", target_pointer_width = "16"))] { + // Unlike driftsort, mergesort only requires len / 2, + // not len - len / 2. let alloc_len = len / 2; cfg_if! { @@ -91,16 +93,26 @@ fn driftsort_main<T, F: FnMut(&T, &T) -> bool, BufT: BufGuard<T>>(v: &mut [T], i // By allocating n elements of memory we can ensure the entire input can // be sorted using stable quicksort, which allows better performance on // random and low-cardinality distributions. However, we still want to - // reduce our memory usage to n / 2 for large inputs. We do this by scaling - // our allocation as max(n / 2, min(n, 8MB)), ensuring we scale like n for - // small inputs and n / 2 for large inputs, without a sudden drop off. We - // also need to ensure our alloc >= MIN_SMALL_SORT_SCRATCH_LEN, as the + // reduce our memory usage to n - n / 2 for large inputs. We do this by scaling + // our allocation as max(n - n / 2, min(n, 8MB)), ensuring we scale like n for + // small inputs and n - n / 2 for large inputs, without a sudden drop off. We + // also need to ensure our alloc >= SMALL_SORT_GENERAL_SCRATCH_LEN, as the // small-sort always needs this much memory. + // + // driftsort will produce unsorted runs of up to min_good_run_len, which + // is at most len - len / 2. + // Unsorted runs need to be processed by quicksort, which requires as much + // scratch space as the run length, therefore the scratch space must be at + // least len - len / 2. + // If min_good_run_len is ever modified, this code must be updated to allocate + // the correct scratch size for it. const MAX_FULL_ALLOC_BYTES: usize = 8_000_000; // 8MB let max_full_alloc = MAX_FULL_ALLOC_BYTES / mem::size_of::<T>(); let len = v.len(); - let alloc_len = - cmp::max(cmp::max(len / 2, cmp::min(len, max_full_alloc)), SMALL_SORT_GENERAL_SCRATCH_LEN); + let alloc_len = cmp::max( + cmp::max(len - len / 2, cmp::min(len, max_full_alloc)), + SMALL_SORT_GENERAL_SCRATCH_LEN, + ); // For small inputs 4KiB of stack storage suffices, which allows us to avoid // calling the (de-)allocator. Benchmarks showed this was quite beneficial. diff --git a/library/core/src/slice/sort/stable/quicksort.rs b/library/core/src/slice/sort/stable/quicksort.rs index 0c8308bfce0..630c6ff9077 100644 --- a/library/core/src/slice/sort/stable/quicksort.rs +++ b/library/core/src/slice/sort/stable/quicksort.rs @@ -7,6 +7,8 @@ use crate::slice::sort::shared::smallsort::StableSmallSortTypeImpl; use crate::{intrinsics, ptr}; /// Sorts `v` recursively using quicksort. +/// `scratch.len()` must be at least `max(v.len() - v.len() / 2, SMALL_SORT_GENERAL_SCRATCH_LEN)` +/// otherwise the implementation may abort. /// /// `limit` when initialized with `c*log(v.len())` for some c ensures we do not /// overflow the stack or go quadratic. diff --git a/library/std/src/sync/once_lock.rs b/library/std/src/sync/once_lock.rs index 49f2dafd8fd..6fc0abbed9e 100644 --- a/library/std/src/sync/once_lock.rs +++ b/library/std/src/sync/once_lock.rs @@ -174,8 +174,6 @@ impl<T> OnceLock<T> { /// /// Waiting for a computation on another thread to finish: /// ```rust - /// #![feature(once_wait)] - /// /// use std::thread; /// use std::sync::OnceLock; /// @@ -189,7 +187,7 @@ impl<T> OnceLock<T> { /// }) /// ``` #[inline] - #[unstable(feature = "once_wait", issue = "127527")] + #[stable(feature = "once_wait", since = "CURRENT_RUSTC_VERSION")] pub fn wait(&self) -> &T { self.once.wait_force(); diff --git a/library/std/src/sync/poison/mutex.rs b/library/std/src/sync/poison/mutex.rs index 01ef71a187f..fb43ada6375 100644 --- a/library/std/src/sync/poison/mutex.rs +++ b/library/std/src/sync/poison/mutex.rs @@ -181,10 +181,29 @@ pub struct Mutex<T: ?Sized> { data: UnsafeCell<T>, } -// these are the only places where `T: Send` matters; all other -// functionality works fine on a single thread. +/// `T` must be `Send` for a [`Mutex`] to be `Send` because it is possible to acquire +/// the owned `T` from the `Mutex` via [`into_inner`]. +/// +/// [`into_inner`]: Mutex::into_inner #[stable(feature = "rust1", since = "1.0.0")] unsafe impl<T: ?Sized + Send> Send for Mutex<T> {} + +/// `T` must be `Send` for [`Mutex`] to be `Sync`. +/// This ensures that the protected data can be accessed safely from multiple threads +/// without causing data races or other unsafe behavior. +/// +/// [`Mutex<T>`] provides mutable access to `T` to one thread at a time. However, it's essential +/// for `T` to be `Send` because it's not safe for non-`Send` structures to be accessed in +/// this manner. For instance, consider [`Rc`], a non-atomic reference counted smart pointer, +/// which is not `Send`. With `Rc`, we can have multiple copies pointing to the same heap +/// allocation with a non-atomic reference count. If we were to use `Mutex<Rc<_>>`, it would +/// only protect one instance of `Rc` from shared access, leaving other copies vulnerable +/// to potential data races. +/// +/// Also note that it is not necessary for `T` to be `Sync` as `&T` is only made available +/// to one thread at a time if `T` is not `Sync`. +/// +/// [`Rc`]: crate::rc::Rc #[stable(feature = "rust1", since = "1.0.0")] unsafe impl<T: ?Sized + Send> Sync for Mutex<T> {} @@ -211,8 +230,17 @@ pub struct MutexGuard<'a, T: ?Sized + 'a> { poison: poison::Guard, } +/// A [`MutexGuard`] is not `Send` to maximize platform portablity. +/// +/// On platforms that use POSIX threads (commonly referred to as pthreads) there is a requirement to +/// release mutex locks on the same thread they were acquired. +/// For this reason, [`MutexGuard`] must not implement `Send` to prevent it being dropped from +/// another thread. #[stable(feature = "rust1", since = "1.0.0")] impl<T: ?Sized> !Send for MutexGuard<'_, T> {} + +/// `T` must be `Sync` for a [`MutexGuard<T>`] to be `Sync` +/// because it is possible to get a `&T` from `&MutexGuard` (via `Deref`). #[stable(feature = "mutexguard", since = "1.19.0")] unsafe impl<T: ?Sized + Sync> Sync for MutexGuard<'_, T> {} diff --git a/library/std/src/sync/poison/once.rs b/library/std/src/sync/poison/once.rs index 27db4b634fb..528b11ca0c1 100644 --- a/library/std/src/sync/poison/once.rs +++ b/library/std/src/sync/poison/once.rs @@ -269,8 +269,6 @@ impl Once { /// # Example /// /// ```rust - /// #![feature(once_wait)] - /// /// use std::sync::Once; /// use std::thread; /// @@ -289,7 +287,7 @@ impl Once { /// If this [`Once`] has been poisoned because an initialization closure has /// panicked, this method will also panic. Use [`wait_force`](Self::wait_force) /// if this behavior is not desired. - #[unstable(feature = "once_wait", issue = "127527")] + #[stable(feature = "once_wait", since = "CURRENT_RUSTC_VERSION")] pub fn wait(&self) { if !self.inner.is_completed() { self.inner.wait(false); @@ -298,7 +296,7 @@ impl Once { /// Blocks the current thread until initialization has completed, ignoring /// poisoning. - #[unstable(feature = "once_wait", issue = "127527")] + #[stable(feature = "once_wait", since = "CURRENT_RUSTC_VERSION")] pub fn wait_force(&self) { if !self.inner.is_completed() { self.inner.wait(true); diff --git a/src/ci/github-actions/jobs.yml b/src/ci/github-actions/jobs.yml index 9af88709625..37299a5a76b 100644 --- a/src/ci/github-actions/jobs.yml +++ b/src/ci/github-actions/jobs.yml @@ -5,7 +5,7 @@ runners: env: { } - &job-linux-4c - os: ubuntu-22.04 + os: ubuntu-24.04 # Free some disk space to avoid running out of space during the build. free_disk: true <<: *base-job @@ -50,7 +50,7 @@ runners: - &job-aarch64-linux # Free some disk space to avoid running out of space during the build. free_disk: true - os: ubuntu-22.04-arm + os: ubuntu-24.04-arm - &job-aarch64-linux-8c os: ubuntu-22.04-arm64-8core-32gb diff --git a/src/ci/scripts/free-disk-space.sh b/src/ci/scripts/free-disk-space.sh index 4a7dad0090b..8850e168145 100755 --- a/src/ci/scripts/free-disk-space.sh +++ b/src/ci/scripts/free-disk-space.sh @@ -1,8 +1,19 @@ #!/bin/bash +set -euo pipefail # Free disk space on Linux GitHub action runners # Script inspired by https://github.com/jlumbroso/free-disk-space +isX86() { + local arch + arch=$(uname -m) + if [ "$arch" = "x86_64" ]; then + return 0 + else + return 1 + fi +} + # print a line of the specified character printSeparationLine() { for ((i = 0; i < 80; i++)); do @@ -14,11 +25,15 @@ printSeparationLine() { # compute available space # REF: https://unix.stackexchange.com/a/42049/60849 # REF: https://stackoverflow.com/a/450821/408734 -getAvailableSpace() { echo $(df -a | awk 'NR > 1 {avail+=$4} END {print avail}'); } +getAvailableSpace() { + df -a | awk 'NR > 1 {avail+=$4} END {print avail}' +} # make Kb human readable (assume the input is Kb) # REF: https://unix.stackexchange.com/a/44087/60849 -formatByteCount() { echo $(numfmt --to=iec-i --suffix=B --padding=7 $1'000'); } +formatByteCount() { + numfmt --to=iec-i --suffix=B --padding=7 "$1"'000' +} # macro to output saved space printSavedSpace() { @@ -58,11 +73,27 @@ removeDir() { dir=${1} local before - before=$(getAvailableSpace) + if [ ! -d "$dir" ]; then + echo "::warning::Directory $dir does not exist, skipping." + else + before=$(getAvailableSpace) + sudo rm -rf "$dir" + printSavedSpace "$before" "Removed $dir" + fi +} + +removeUnusedDirectories() { + local dirs_to_remove=( + "/usr/local/lib/android" + "/usr/share/dotnet" - sudo rm -rf "$dir" || true + # Haskell runtime + "/usr/local/.ghcup" + ) - printSavedSpace "$before" "$dir" + for dir in "${dirs_to_remove[@]}"; do + removeDir "$dir" + done } execAndMeasureSpaceChange() { @@ -79,21 +110,29 @@ execAndMeasureSpaceChange() { # Remove large packages # REF: https://github.com/apache/flink/blob/master/tools/azure-pipelines/free_disk_space.sh cleanPackages() { - sudo apt-get -qq remove -y --fix-missing \ - '^aspnetcore-.*' \ - '^dotnet-.*' \ - '^llvm-.*' \ - 'php.*' \ - '^mongodb-.*' \ - '^mysql-.*' \ - 'azure-cli' \ - 'google-chrome-stable' \ - 'firefox' \ - 'powershell' \ - 'mono-devel' \ - 'libgl1-mesa-dri' \ - 'google-cloud-sdk' \ - 'google-cloud-cli' + local packages=( + '^aspnetcore-.*' + '^dotnet-.*' + '^llvm-.*' + '^mongodb-.*' + '^mysql-.*' + 'azure-cli' + 'firefox' + 'libgl1-mesa-dri' + 'mono-devel' + 'php.*' + ) + + if isX86; then + packages+=( + 'google-chrome-stable' + 'google-cloud-cli' + 'google-cloud-sdk' + 'powershell' + ) + fi + + sudo apt-get -qq remove -y --fix-missing "${packages[@]}" sudo apt-get autoremove -y || echo "::warning::The command [sudo apt-get autoremove -y] failed" sudo apt-get clean || echo "::warning::The command [sudo apt-get clean] failed failed" @@ -101,9 +140,9 @@ cleanPackages() { # Remove Docker images cleanDocker() { - echo "Removing the following docker images:" + echo "=> Removing the following docker images:" sudo docker image ls - echo "Removing docker images..." + echo "=> Removing docker images..." sudo docker image prune --all --force || true } @@ -121,17 +160,12 @@ AVAILABLE_INITIAL=$(getAvailableSpace) printDF "BEFORE CLEAN-UP:" echo "" -removeDir /usr/local/lib/android -removeDir /usr/share/dotnet - -# Haskell runtime -removeDir /opt/ghc -removeDir /usr/local/.ghcup - -execAndMeasureSpaceChange cleanPackages "Large misc. packages" +execAndMeasureSpaceChange cleanPackages "Unused packages" execAndMeasureSpaceChange cleanDocker "Docker images" execAndMeasureSpaceChange cleanSwap "Swap storage" +removeUnusedDirectories + # Output saved space statistic echo "" printDF "AFTER CLEAN-UP:" diff --git a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs index 287bdc9a6fd..0aaef91e48a 100644 --- a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs +++ b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs @@ -116,6 +116,7 @@ fn check_rvalue<'tcx>( Rvalue::CopyForDeref(place) => check_place(tcx, *place, span, body, msrv), Rvalue::Repeat(operand, _) | Rvalue::Use(operand) + | Rvalue::WrapUnsafeBinder(operand, _) | Rvalue::Cast( CastKind::PointerWithExposedProvenance | CastKind::IntToInt @@ -289,7 +290,8 @@ fn check_place<'tcx>(tcx: TyCtxt<'tcx>, place: Place<'tcx>, span: Span, body: &B | ProjectionElem::Downcast(..) | ProjectionElem::Subslice { .. } | ProjectionElem::Subtype(_) - | ProjectionElem::Index(_) => {}, + | ProjectionElem::Index(_) + | ProjectionElem::UnwrapUnsafeBinder(_) => {}, } } diff --git a/src/tools/miri/src/machine.rs b/src/tools/miri/src/machine.rs index ff4b0ac3827..4735db48e81 100644 --- a/src/tools/miri/src/machine.rs +++ b/src/tools/miri/src/machine.rs @@ -11,6 +11,7 @@ use std::{fmt, process}; use rand::rngs::StdRng; use rand::{Rng, SeedableRng}; use rustc_abi::{Align, ExternAbi, Size}; +use rustc_apfloat::{Float, FloatConvert}; use rustc_attr_parsing::InlineAttr; use rustc_data_structures::fx::{FxHashMap, FxHashSet}; #[allow(unused)] @@ -1132,20 +1133,24 @@ impl<'tcx> Machine<'tcx> for MiriMachine<'tcx> { } #[inline(always)] - fn generate_nan< - F1: rustc_apfloat::Float + rustc_apfloat::FloatConvert<F2>, - F2: rustc_apfloat::Float, - >( + fn generate_nan<F1: Float + FloatConvert<F2>, F2: Float>( ecx: &InterpCx<'tcx, Self>, inputs: &[F1], ) -> F2 { ecx.generate_nan(inputs) } + #[inline(always)] + fn equal_float_min_max<F: Float>(ecx: &MiriInterpCx<'tcx>, a: F, b: F) -> F { + ecx.equal_float_min_max(a, b) + } + + #[inline(always)] fn ub_checks(ecx: &InterpCx<'tcx, Self>) -> InterpResult<'tcx, bool> { interp_ok(ecx.tcx.sess.ub_checks()) } + #[inline(always)] fn thread_local_static_pointer( ecx: &mut MiriInterpCx<'tcx>, def_id: DefId, diff --git a/src/tools/miri/src/operator.rs b/src/tools/miri/src/operator.rs index 124b2a765a9..a3c063d0f37 100644 --- a/src/tools/miri/src/operator.rs +++ b/src/tools/miri/src/operator.rs @@ -115,4 +115,11 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> { nan } } + + fn equal_float_min_max<F: Float>(&self, a: F, b: F) -> F { + let this = self.eval_context_ref(); + // Return one side non-deterministically. + let mut rand = this.machine.rng.borrow_mut(); + if rand.gen() { a } else { b } + } } diff --git a/src/tools/miri/tests/pass/float.rs b/src/tools/miri/tests/pass/float.rs index 4de315e3589..2f4f64b1aa8 100644 --- a/src/tools/miri/tests/pass/float.rs +++ b/src/tools/miri/tests/pass/float.rs @@ -31,6 +31,7 @@ fn main() { test_fast(); test_algebraic(); test_fmuladd(); + test_min_max_nondet(); } trait Float: Copy + PartialEq + Debug { @@ -1211,3 +1212,30 @@ fn test_fmuladd() { test_operations_f32(0.1, 0.2, 0.3); test_operations_f64(1.1, 1.2, 1.3); } + +/// `min` and `max` on equal arguments are non-deterministic. +fn test_min_max_nondet() { + /// Ensure that if we call the closure often enough, we see both `true` and `false.` + #[track_caller] + fn ensure_both(f: impl Fn() -> bool) { + let rounds = 16; + let first = f(); + for _ in 1..rounds { + if f() != first { + // We saw two different values! + return; + } + } + // We saw the same thing N times. + panic!("expected non-determinism, got {rounds} times the same result: {first:?}"); + } + + ensure_both(|| f16::min(0.0, -0.0).is_sign_positive()); + ensure_both(|| f16::max(0.0, -0.0).is_sign_positive()); + ensure_both(|| f32::min(0.0, -0.0).is_sign_positive()); + ensure_both(|| f32::max(0.0, -0.0).is_sign_positive()); + ensure_both(|| f64::min(0.0, -0.0).is_sign_positive()); + ensure_both(|| f64::max(0.0, -0.0).is_sign_positive()); + ensure_both(|| f128::min(0.0, -0.0).is_sign_positive()); + ensure_both(|| f128::max(0.0, -0.0).is_sign_positive()); +} diff --git a/tests/crashes/135210.rs b/tests/crashes/135210.rs deleted file mode 100644 index acb61e21090..00000000000 --- a/tests/crashes/135210.rs +++ /dev/null @@ -1,8 +0,0 @@ -//@ known-bug: #135210 - -#![feature(const_trait_impl)] -const _: fn(&String) = |s| { - &*s as &str; -}; - -fn main() {} diff --git a/tests/ui/array-slice-vec/driftsort-off-by-one-issue-136103.rs b/tests/ui/array-slice-vec/driftsort-off-by-one-issue-136103.rs new file mode 100644 index 00000000000..42197ff102d --- /dev/null +++ b/tests/ui/array-slice-vec/driftsort-off-by-one-issue-136103.rs @@ -0,0 +1,10 @@ +//@ run-pass +// Ensures that driftsort doesn't crash under specific slice +// length and memory size. +// Based on the example given in https://github.com/rust-lang/rust/issues/136103. +fn main() { + let n = 127; + let mut objs: Vec<_> = + (0..n).map(|i| [(i % 2) as u8; 125001]).collect(); + objs.sort(); +} diff --git a/tests/ui/associated-inherent-types/bugs/wf-check-skipped.next.stderr b/tests/ui/associated-inherent-types/bugs/wf-check-skipped.next.stderr index bf53089675d..81ace4ebb6d 100644 --- a/tests/ui/associated-inherent-types/bugs/wf-check-skipped.next.stderr +++ b/tests/ui/associated-inherent-types/bugs/wf-check-skipped.next.stderr @@ -5,6 +5,8 @@ LL | fn main() -> Foo::Bar::<Vec<[u32]>> {} | ^^^^^^^^^^ doesn't have a size known at compile-time | = help: the trait `Sized` is not implemented for `[u32]` +note: required by an implicit `Sized` bound in `Vec` + --> $SRC_DIR/alloc/src/vec/mod.rs:LL:COL error: aborting due to 1 previous error diff --git a/tests/ui/const-generics/issues/issue-88119.stderr b/tests/ui/const-generics/issues/issue-88119.stderr index f219c90849a..c497f1b6d0b 100644 --- a/tests/ui/const-generics/issues/issue-88119.stderr +++ b/tests/ui/const-generics/issues/issue-88119.stderr @@ -6,35 +6,29 @@ LL | #![feature(const_trait_impl, generic_const_exprs)] | = help: remove one of these features -error[E0284]: type annotations needed: cannot normalize `<&T as ConstName>::{constant#0}` - --> $DIR/issue-88119.rs:19:49 +error[E0284]: type annotations needed: cannot satisfy `the constant `name_len::<T>()` can be evaluated` + --> $DIR/issue-88119.rs:21:5 | -LL | impl<T: ?Sized + ConstName> const ConstName for &T - | ^^ cannot normalize `<&T as ConstName>::{constant#0}` +LL | [(); name_len::<T>()]:, + | ^^^^^^^^^^^^^^^^^^^^^ cannot satisfy `the constant `name_len::<T>()` can be evaluated` | -note: required for `&T` to implement `~const ConstName` - --> $DIR/issue-88119.rs:19:35 +note: required by a bound in `<&T as ConstName>` + --> $DIR/issue-88119.rs:21:10 | -LL | impl<T: ?Sized + ConstName> const ConstName for &T - | ^^^^^^^^^ ^^ -LL | where LL | [(); name_len::<T>()]:, - | --------------------- unsatisfied trait bound introduced here + | ^^^^^^^^^^^^^^^ required by this bound in `<&T as ConstName>` -error[E0284]: type annotations needed: cannot normalize `<&mut T as ConstName>::{constant#0}` - --> $DIR/issue-88119.rs:26:49 +error[E0284]: type annotations needed: cannot satisfy `the constant `name_len::<T>()` can be evaluated` + --> $DIR/issue-88119.rs:28:5 | -LL | impl<T: ?Sized + ConstName> const ConstName for &mut T - | ^^^^^^ cannot normalize `<&mut T as ConstName>::{constant#0}` +LL | [(); name_len::<T>()]:, + | ^^^^^^^^^^^^^^^^^^^^^ cannot satisfy `the constant `name_len::<T>()` can be evaluated` | -note: required for `&mut T` to implement `~const ConstName` - --> $DIR/issue-88119.rs:26:35 +note: required by a bound in `<&mut T as ConstName>` + --> $DIR/issue-88119.rs:28:10 | -LL | impl<T: ?Sized + ConstName> const ConstName for &mut T - | ^^^^^^^^^ ^^^^^^ -LL | where LL | [(); name_len::<T>()]:, - | --------------------- unsatisfied trait bound introduced here + | ^^^^^^^^^^^^^^^ required by this bound in `<&mut T as ConstName>` error: aborting due to 3 previous errors diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.next.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.next.stderr index 1b76669ccb0..4f685c508c7 100644 --- a/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.next.stderr +++ b/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.next.stderr @@ -16,23 +16,13 @@ LL | where LL | T: AsExpression<Self::SqlType>, | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Foo::check` -error[E0277]: the trait bound `&str: AsExpression<Integer>` is not satisfied - --> $DIR/as_expression.rs:55:15 - | -LL | SelectInt.check("bar"); - | ^^^^^ the trait `AsExpression<Integer>` is not implemented for `&str` - | - = help: the trait `AsExpression<Integer>` is not implemented for `&str` - but trait `AsExpression<Text>` is implemented for it - = help: for that trait implementation, expected `Text`, found `Integer` - error[E0271]: type mismatch resolving `<SelectInt as Expression>::SqlType == Text` --> $DIR/as_expression.rs:55:5 | LL | SelectInt.check("bar"); | ^^^^^^^^^^^^^^^^^^^^^^ expected `Text`, found `Integer` -error: aborting due to 3 previous errors +error: aborting due to 2 previous errors Some errors have detailed explanations: E0271, E0277. For more information about an error, try `rustc --explain E0271`. diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.rs b/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.rs index 583b3c4675a..48c1ed2b02d 100644 --- a/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.rs +++ b/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.rs @@ -53,7 +53,7 @@ impl<T> Foo for T where T: Expression {} fn main() { SelectInt.check("bar"); - //~^ ERROR the trait bound `&str: AsExpression<Integer>` is not satisfied - //[next]~| the trait bound `&str: AsExpression<<SelectInt as Expression>::SqlType>` is not satisfied + //[current]~^ ERROR the trait bound `&str: AsExpression<Integer>` is not satisfied + //[next]~^^ the trait bound `&str: AsExpression<<SelectInt as Expression>::SqlType>` is not satisfied //[next]~| type mismatch } diff --git a/tests/ui/impl-trait/in-trait/alias-bounds-when-not-wf.stderr b/tests/ui/impl-trait/in-trait/alias-bounds-when-not-wf.stderr index 1cfc2a6d944..a95670ced86 100644 --- a/tests/ui/impl-trait/in-trait/alias-bounds-when-not-wf.stderr +++ b/tests/ui/impl-trait/in-trait/alias-bounds-when-not-wf.stderr @@ -18,6 +18,11 @@ help: this trait has no implementations, consider adding one | LL | trait Foo {} | ^^^^^^^^^ +note: required by a bound in `A` + --> $DIR/alias-bounds-when-not-wf.rs:8:11 + | +LL | type A<T: Foo> = T; + | ^^^ required by this bound in `A` error[E0277]: the trait bound `usize: Foo` is not satisfied --> $DIR/alias-bounds-when-not-wf.rs:16:10 diff --git a/tests/ui/liveness/liveness-unused.rs b/tests/ui/liveness/liveness-unused.rs index ba635e6638c..49e7044aeda 100644 --- a/tests/ui/liveness/liveness-unused.rs +++ b/tests/ui/liveness/liveness-unused.rs @@ -2,6 +2,7 @@ #![deny(unused_variables)] #![deny(unused_assignments)] #![allow(dead_code, non_camel_case_types, trivial_numeric_casts, dropping_copy_types)] +#![feature(intrinsics)] use std::ops::AddAssign; @@ -137,5 +138,10 @@ fn f7() { drop(a); } +// unused params warnings are not needed for intrinsic functions without bodies +#[rustc_intrinsic] +unsafe fn simd_shuffle<T, I, U>(a: T, b: T, i: I) -> U; + + fn main() { } diff --git a/tests/ui/liveness/liveness-unused.stderr b/tests/ui/liveness/liveness-unused.stderr index f6c478ddbc7..a69fc10dff2 100644 --- a/tests/ui/liveness/liveness-unused.stderr +++ b/tests/ui/liveness/liveness-unused.stderr @@ -1,5 +1,5 @@ warning: unreachable statement - --> $DIR/liveness-unused.rs:92:9 + --> $DIR/liveness-unused.rs:93:9 | LL | continue; | -------- any code following this expression is unreachable @@ -14,7 +14,7 @@ LL | #![warn(unused)] = note: `#[warn(unreachable_code)]` implied by `#[warn(unused)]` error: unused variable: `x` - --> $DIR/liveness-unused.rs:8:7 + --> $DIR/liveness-unused.rs:9:7 | LL | fn f1(x: isize) { | ^ help: if this is intentional, prefix it with an underscore: `_x` @@ -26,25 +26,25 @@ LL | #![deny(unused_variables)] | ^^^^^^^^^^^^^^^^ error: unused variable: `x` - --> $DIR/liveness-unused.rs:12:8 + --> $DIR/liveness-unused.rs:13:8 | LL | fn f1b(x: &mut isize) { | ^ help: if this is intentional, prefix it with an underscore: `_x` error: unused variable: `x` - --> $DIR/liveness-unused.rs:20:9 + --> $DIR/liveness-unused.rs:21:9 | LL | let x: isize; | ^ help: if this is intentional, prefix it with an underscore: `_x` error: unused variable: `x` - --> $DIR/liveness-unused.rs:25:9 + --> $DIR/liveness-unused.rs:26:9 | LL | let x = 3; | ^ help: if this is intentional, prefix it with an underscore: `_x` error: variable `x` is assigned to, but never used - --> $DIR/liveness-unused.rs:30:13 + --> $DIR/liveness-unused.rs:31:13 | LL | let mut x = 3; | ^ @@ -52,7 +52,7 @@ LL | let mut x = 3; = note: consider using `_x` instead error: value assigned to `x` is never read - --> $DIR/liveness-unused.rs:32:5 + --> $DIR/liveness-unused.rs:33:5 | LL | x += 4; | ^ @@ -65,7 +65,7 @@ LL | #![deny(unused_assignments)] | ^^^^^^^^^^^^^^^^^^ error: variable `z` is assigned to, but never used - --> $DIR/liveness-unused.rs:37:13 + --> $DIR/liveness-unused.rs:38:13 | LL | let mut z = 3; | ^ @@ -73,31 +73,31 @@ LL | let mut z = 3; = note: consider using `_z` instead error: unused variable: `i` - --> $DIR/liveness-unused.rs:59:12 + --> $DIR/liveness-unused.rs:60:12 | LL | Some(i) => { | ^ help: if this is intentional, prefix it with an underscore: `_i` error: unused variable: `x` - --> $DIR/liveness-unused.rs:79:9 + --> $DIR/liveness-unused.rs:80:9 | LL | for x in 1..10 { } | ^ help: if this is intentional, prefix it with an underscore: `_x` error: unused variable: `x` - --> $DIR/liveness-unused.rs:84:10 + --> $DIR/liveness-unused.rs:85:10 | LL | for (x, _) in [1, 2, 3].iter().enumerate() { } | ^ help: if this is intentional, prefix it with an underscore: `_x` error: unused variable: `x` - --> $DIR/liveness-unused.rs:89:13 + --> $DIR/liveness-unused.rs:90:13 | LL | for (_, x) in [1, 2, 3].iter().enumerate() { | ^ help: if this is intentional, prefix it with an underscore: `_x` error: variable `x` is assigned to, but never used - --> $DIR/liveness-unused.rs:112:9 + --> $DIR/liveness-unused.rs:113:9 | LL | let x; | ^ @@ -105,7 +105,7 @@ LL | let x; = note: consider using `_x` instead error: value assigned to `x` is never read - --> $DIR/liveness-unused.rs:116:9 + --> $DIR/liveness-unused.rs:117:9 | LL | x = 0; | ^ diff --git a/tests/ui/traits/const-traits/enforce-deref-on-adjust.rs b/tests/ui/traits/const-traits/enforce-deref-on-adjust.rs new file mode 100644 index 00000000000..d5240b7e18d --- /dev/null +++ b/tests/ui/traits/const-traits/enforce-deref-on-adjust.rs @@ -0,0 +1,28 @@ +//@ check-pass + +#![feature(const_deref)] +#![feature(const_trait_impl)] + +use std::ops::Deref; + +struct Wrap<T>(T); +struct Foo; + +impl Foo { + const fn call(&self) {} +} + +impl<T> const Deref for Wrap<T> { + type Target = T; + + fn deref(&self) -> &Self::Target { + &self.0 + } +} + +const fn foo() { + let x = Wrap(Foo); + x.call(); +} + +fn main() {} diff --git a/tests/ui/traits/next-solver/canonical/const-region-infer-to-static-in-binder.stderr b/tests/ui/traits/next-solver/canonical/const-region-infer-to-static-in-binder.stderr index 377dfc8b529..425f2d59222 100644 --- a/tests/ui/traits/next-solver/canonical/const-region-infer-to-static-in-binder.stderr +++ b/tests/ui/traits/next-solver/canonical/const-region-infer-to-static-in-binder.stderr @@ -1,8 +1,8 @@ -error[E0284]: type annotations needed: cannot normalize `X::{constant#0}` +error[E0284]: type annotations needed: cannot satisfy `the constant `{ || {} }` can be evaluated` --> $DIR/const-region-infer-to-static-in-binder.rs:4:10 | LL | struct X<const FN: fn() = { || {} }>; - | ^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot normalize `X::{constant#0}` + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot satisfy `the constant `{ || {} }` can be evaluated` error: using function pointers as const generic parameters is forbidden --> $DIR/const-region-infer-to-static-in-binder.rs:4:20 diff --git a/tests/ui/traits/next-solver/specialization-transmute.stderr b/tests/ui/traits/next-solver/specialization-transmute.stderr index b96bfab927d..2d0c503bc95 100644 --- a/tests/ui/traits/next-solver/specialization-transmute.stderr +++ b/tests/ui/traits/next-solver/specialization-transmute.stderr @@ -10,11 +10,11 @@ LL | #![feature(specialization)] error: cannot normalize `<T as Default>::Id: '_` -error[E0284]: type annotations needed: cannot normalize `<T as Default>::Id` +error[E0282]: type annotations needed --> $DIR/specialization-transmute.rs:15:23 | LL | fn intu(&self) -> &Self::Id { - | ^^^^^^^^^ cannot normalize `<T as Default>::Id` + | ^^^^^^^^^ cannot infer type for reference `&<T as Default>::Id` error[E0284]: type annotations needed: cannot satisfy `<T as Default>::Id normalizes-to T` --> $DIR/specialization-transmute.rs:17:9 @@ -36,4 +36,5 @@ LL | fn transmute<T: Default<Id = U>, U: Copy>(t: T) -> U { error: aborting due to 4 previous errors; 1 warning emitted -For more information about this error, try `rustc --explain E0284`. +Some errors have detailed explanations: E0282, E0284. +For more information about an error, try `rustc --explain E0282`. diff --git a/tests/ui/typeck/issue-114918/const-in-impl-fn-return-type.next.stderr b/tests/ui/typeck/issue-114918/const-in-impl-fn-return-type.next.stderr index 1bcc0dbaf67..92ad83c3300 100644 --- a/tests/ui/typeck/issue-114918/const-in-impl-fn-return-type.next.stderr +++ b/tests/ui/typeck/issue-114918/const-in-impl-fn-return-type.next.stderr @@ -9,6 +9,8 @@ error: the constant `N` is not of type `usize` | LL | fn func<const N: u32>() -> [(); N]; | ^^^^^^^ expected `usize`, found `u32` + | + = note: the length of array `[(); N]` must be type `usize` error: aborting due to 2 previous errors diff --git a/tests/ui/union/union-derive-eq.next.stderr b/tests/ui/union/union-derive-eq.next.stderr index 3952b1f1284..151ceebe1ba 100644 --- a/tests/ui/union/union-derive-eq.next.stderr +++ b/tests/ui/union/union-derive-eq.next.stderr @@ -7,6 +7,8 @@ LL | union U2 { LL | a: PartialEqNotEq, | ^^^^^^^^^^^^^^^^^ the trait `Eq` is not implemented for `PartialEqNotEq` | +note: required by a bound in `AssertParamIsEq` + --> $SRC_DIR/core/src/cmp.rs:LL:COL = note: this error originates in the derive macro `Eq` (in Nightly builds, run with -Z macro-backtrace for more info) help: consider annotating `PartialEqNotEq` with `#[derive(Eq)]` | diff --git a/tests/ui/unsafe-binders/expr.rs b/tests/ui/unsafe-binders/expr.rs index 0fe68751f0a..d437d8f8ac0 100644 --- a/tests/ui/unsafe-binders/expr.rs +++ b/tests/ui/unsafe-binders/expr.rs @@ -1,3 +1,5 @@ +//@ check-pass + #![feature(unsafe_binders)] //~^ WARN the feature `unsafe_binders` is incomplete @@ -7,8 +9,6 @@ fn main() { unsafe { let x = 1; let binder: unsafe<'a> &'a i32 = wrap_binder!(&x); - //~^ ERROR unsafe binder casts are not fully implemented let rx = *unwrap_binder!(binder); - //~^ ERROR unsafe binder casts are not fully implemented } } diff --git a/tests/ui/unsafe-binders/expr.stderr b/tests/ui/unsafe-binders/expr.stderr index 78a288e10a3..07026e18e12 100644 --- a/tests/ui/unsafe-binders/expr.stderr +++ b/tests/ui/unsafe-binders/expr.stderr @@ -1,5 +1,5 @@ warning: the feature `unsafe_binders` is incomplete and may not be safe to use and/or cause compiler crashes - --> $DIR/expr.rs:1:12 + --> $DIR/expr.rs:3:12 | LL | #![feature(unsafe_binders)] | ^^^^^^^^^^^^^^ @@ -7,17 +7,5 @@ LL | #![feature(unsafe_binders)] = note: see issue #130516 <https://github.com/rust-lang/rust/issues/130516> for more information = note: `#[warn(incomplete_features)]` on by default -error: unsafe binder casts are not fully implemented - --> $DIR/expr.rs:9:55 - | -LL | let binder: unsafe<'a> &'a i32 = wrap_binder!(&x); - | ^^ - -error: unsafe binder casts are not fully implemented - --> $DIR/expr.rs:11:34 - | -LL | let rx = *unwrap_binder!(binder); - | ^^^^^^ - -error: aborting due to 2 previous errors; 1 warning emitted +warning: 1 warning emitted diff --git a/tests/ui/unsafe-binders/mismatch.rs b/tests/ui/unsafe-binders/mismatch.rs index 731fe2d1ce9..840d938cbe9 100644 --- a/tests/ui/unsafe-binders/mismatch.rs +++ b/tests/ui/unsafe-binders/mismatch.rs @@ -5,38 +5,31 @@ use std::unsafe_binder::{wrap_binder, unwrap_binder}; fn a() { let _: unsafe<'a> &'a i32 = wrap_binder!(&()); - //~^ ERROR unsafe binder casts are not fully implemented - //~| ERROR mismatched types + //~^ ERROR mismatched types } fn b() { let _: i32 = wrap_binder!(&()); - //~^ ERROR unsafe binder casts are not fully implemented - //~| ERROR `wrap_binder!()` can only wrap into unsafe binder + //~^ ERROR `wrap_binder!()` can only wrap into unsafe binder } fn c() { let y = 1; unwrap_binder!(y); - //~^ ERROR unsafe binder casts are not fully implemented - //~| ERROR expected unsafe binder, found integer as input + //~^ ERROR expected unsafe binder, found integer as input } fn d() { let unknown = Default::default(); + //~^ ERROR type annotations needed unwrap_binder!(unknown); - //~^ ERROR unsafe binder casts are not fully implemented - // FIXME(unsafe_binders): This should report ambiguity once we've removed - // the error above which taints the infcx. } fn e() { let x = wrap_binder!(&42); - //~^ ERROR unsafe binder casts are not fully implemented + //~^ ERROR type annotations needed // Currently, type inference doesn't flow backwards for unsafe binders. // It could, perhaps, but that may cause even more surprising corners. - // FIXME(unsafe_binders): This should report ambiguity once we've removed - // the error above which taints the infcx. let _: unsafe<'a> &'a i32 = x; } diff --git a/tests/ui/unsafe-binders/mismatch.stderr b/tests/ui/unsafe-binders/mismatch.stderr index a720e5dbdc1..f64db92eb65 100644 --- a/tests/ui/unsafe-binders/mismatch.stderr +++ b/tests/ui/unsafe-binders/mismatch.stderr @@ -7,12 +7,6 @@ LL | #![feature(unsafe_binders)] = note: see issue #130516 <https://github.com/rust-lang/rust/issues/130516> for more information = note: `#[warn(incomplete_features)]` on by default -error: unsafe binder casts are not fully implemented - --> $DIR/mismatch.rs:7:46 - | -LL | let _: unsafe<'a> &'a i32 = wrap_binder!(&()); - | ^^^ - error[E0308]: mismatched types --> $DIR/mismatch.rs:7:46 | @@ -22,14 +16,8 @@ LL | let _: unsafe<'a> &'a i32 = wrap_binder!(&()); = note: expected reference `&i32` found reference `&()` -error: unsafe binder casts are not fully implemented - --> $DIR/mismatch.rs:13:31 - | -LL | let _: i32 = wrap_binder!(&()); - | ^^^ - error: `wrap_binder!()` can only wrap into unsafe binder, not `i32` - --> $DIR/mismatch.rs:13:18 + --> $DIR/mismatch.rs:12:18 | LL | let _: i32 = wrap_binder!(&()); | ^^^^^^^^^^^^^^^^^ @@ -37,32 +25,35 @@ LL | let _: i32 = wrap_binder!(&()); = note: unsafe binders are the only valid output of wrap = note: this error originates in the macro `wrap_binder` (in Nightly builds, run with -Z macro-backtrace for more info) -error: unsafe binder casts are not fully implemented - --> $DIR/mismatch.rs:20:20 - | -LL | unwrap_binder!(y); - | ^ - error: expected unsafe binder, found integer as input of `unwrap_binder!()` - --> $DIR/mismatch.rs:20:20 + --> $DIR/mismatch.rs:18:20 | LL | unwrap_binder!(y); | ^ | = note: only an unsafe binder type can be unwrapped -error: unsafe binder casts are not fully implemented - --> $DIR/mismatch.rs:27:20 +error[E0282]: type annotations needed + --> $DIR/mismatch.rs:23:9 | +LL | let unknown = Default::default(); + | ^^^^^^^ +LL | LL | unwrap_binder!(unknown); - | ^^^^^^^ + | ------- type must be known at this point + | +help: consider giving `unknown` an explicit type + | +LL | let unknown: /* Type */ = Default::default(); + | ++++++++++++ -error: unsafe binder casts are not fully implemented - --> $DIR/mismatch.rs:34:26 +error[E0282]: type annotations needed + --> $DIR/mismatch.rs:29:26 | LL | let x = wrap_binder!(&42); - | ^^^ + | ^^^ cannot infer type -error: aborting due to 8 previous errors; 1 warning emitted +error: aborting due to 5 previous errors; 1 warning emitted -For more information about this error, try `rustc --explain E0308`. +Some errors have detailed explanations: E0282, E0308. +For more information about an error, try `rustc --explain E0282`. diff --git a/tests/ui/unsafe-binders/moves.rs b/tests/ui/unsafe-binders/moves.rs new file mode 100644 index 00000000000..5bfcee62402 --- /dev/null +++ b/tests/ui/unsafe-binders/moves.rs @@ -0,0 +1,41 @@ +//@ known-bug: unknown + +#![feature(unsafe_binders)] +// FIXME(unsafe_binders) ~^ WARN the feature `unsafe_binders` is incomplete + +use std::unsafe_binder::{wrap_binder, unwrap_binder}; +use std::mem::{drop, ManuallyDrop}; + +struct NotCopyInner; +type NotCopy = ManuallyDrop<NotCopyInner>; + +fn use_after_wrap() { + unsafe { + let base = NotCopy; + let binder: unsafe<> NotCopy = wrap_binder!(base); + drop(base); + // FIXME(unsafe_binders) ~^ ERROR use of moved value: `base` + } +} + +fn move_out_of_wrap() { + unsafe { + let binder: unsafe<> NotCopy = wrap_binder!(NotCopy); + drop(unwrap_binder!(binder)); + drop(unwrap_binder!(binder)); + // FIXME(unsafe_binders) ~^ ERROR use of moved value: `binder` + } +} + +fn not_conflicting() { + unsafe { + let binder: unsafe<> (NotCopy, NotCopy) = wrap_binder!((NotCopy, NotCopy)); + drop(unwrap_binder!(binder).0); + drop(unwrap_binder!(binder).1); + // ^ NOT a problem. + drop(unwrap_binder!(binder).0); + // FIXME(unsafe_binders) ~^ ERROR use of moved value: `binder.0` + } +} + +fn main() {} diff --git a/tests/ui/unsafe-binders/moves.stderr b/tests/ui/unsafe-binders/moves.stderr new file mode 100644 index 00000000000..ca507964008 --- /dev/null +++ b/tests/ui/unsafe-binders/moves.stderr @@ -0,0 +1,85 @@ +error[E0423]: expected value, found type alias `NotCopy` + --> $DIR/moves.rs:14:20 + | +LL | let base = NotCopy; + | ^^^^^^^ + | + = note: can't use a type alias as a constructor + +error[E0423]: expected value, found type alias `NotCopy` + --> $DIR/moves.rs:23:53 + | +LL | let binder: unsafe<> NotCopy = wrap_binder!(NotCopy); + | ^^^^^^^ + | + = note: can't use a type alias as a constructor + +error[E0423]: expected value, found type alias `NotCopy` + --> $DIR/moves.rs:32:65 + | +LL | let binder: unsafe<> (NotCopy, NotCopy) = wrap_binder!((NotCopy, NotCopy)); + | ^^^^^^^ + | + = note: can't use a type alias as a constructor + +error[E0423]: expected value, found type alias `NotCopy` + --> $DIR/moves.rs:32:74 + | +LL | let binder: unsafe<> (NotCopy, NotCopy) = wrap_binder!((NotCopy, NotCopy)); + | ^^^^^^^ + | + = note: can't use a type alias as a constructor + +warning: the feature `unsafe_binders` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/moves.rs:3:12 + | +LL | #![feature(unsafe_binders)] + | ^^^^^^^^^^^^^^ + | + = note: see issue #130516 <https://github.com/rust-lang/rust/issues/130516> for more information + = note: `#[warn(incomplete_features)]` on by default + +error[E0277]: the trait bound `NotCopyInner: Copy` is not satisfied + --> $DIR/moves.rs:15:21 + | +LL | let binder: unsafe<> NotCopy = wrap_binder!(base); + | ^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `NotCopyInner` + | + = note: required for `ManuallyDrop<NotCopyInner>` to implement `Copy` +help: consider annotating `NotCopyInner` with `#[derive(Copy)]` + | +LL + #[derive(Copy)] +LL | struct NotCopyInner; + | + +error[E0277]: the trait bound `NotCopyInner: Copy` is not satisfied + --> $DIR/moves.rs:23:21 + | +LL | let binder: unsafe<> NotCopy = wrap_binder!(NotCopy); + | ^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `NotCopyInner` + | + = note: required for `ManuallyDrop<NotCopyInner>` to implement `Copy` +help: consider annotating `NotCopyInner` with `#[derive(Copy)]` + | +LL + #[derive(Copy)] +LL | struct NotCopyInner; + | + +error[E0277]: the trait bound `NotCopyInner: Copy` is not satisfied + --> $DIR/moves.rs:32:21 + | +LL | let binder: unsafe<> (NotCopy, NotCopy) = wrap_binder!((NotCopy, NotCopy)); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `NotCopyInner` + | + = note: required for `ManuallyDrop<NotCopyInner>` to implement `Copy` + = note: required because it appears within the type `(ManuallyDrop<NotCopyInner>, ManuallyDrop<NotCopyInner>)` +help: consider annotating `NotCopyInner` with `#[derive(Copy)]` + | +LL + #[derive(Copy)] +LL | struct NotCopyInner; + | + +error: aborting due to 7 previous errors; 1 warning emitted + +Some errors have detailed explanations: E0277, E0423. +For more information about an error, try `rustc --explain E0277`. diff --git a/tests/ui/wf/wf-normalization-sized.next.stderr b/tests/ui/wf/wf-normalization-sized.next.stderr index 1e898fb7b78..83b56bb6b19 100644 --- a/tests/ui/wf/wf-normalization-sized.next.stderr +++ b/tests/ui/wf/wf-normalization-sized.next.stderr @@ -5,6 +5,7 @@ LL | const _: <[[[[[[u8]]]]]] as WellUnformed>::RequestNormalize = (); | ^^^^^^^^^^^^^^ doesn't have a size known at compile-time | = help: the trait `Sized` is not implemented for `[[[[[u8]]]]]` + = note: slice and array elements must have `Sized` type error[E0277]: the size for values of type `[[[[[u8]]]]]` cannot be known at compilation time --> $DIR/wf-normalization-sized.rs:19:11 @@ -13,6 +14,7 @@ LL | const _: <[[[[[[u8]]]]]] as WellUnformed>::RequestNormalize = (); | ^^^^^^^^^^^^^^ doesn't have a size known at compile-time | = help: the trait `Sized` is not implemented for `[[[[[u8]]]]]` + = note: slice and array elements must have `Sized` type = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` error[E0277]: the size for values of type `str` cannot be known at compilation time @@ -22,6 +24,8 @@ LL | const _: <Vec<str> as WellUnformed>::RequestNormalize = (); | ^^^^^^^^ doesn't have a size known at compile-time | = help: the trait `Sized` is not implemented for `str` +note: required by an implicit `Sized` bound in `Vec` + --> $SRC_DIR/alloc/src/vec/mod.rs:LL:COL error[E0277]: the size for values of type `str` cannot be known at compilation time --> $DIR/wf-normalization-sized.rs:22:11 @@ -30,6 +34,8 @@ LL | const _: <Vec<str> as WellUnformed>::RequestNormalize = (); | ^^^^^^^^ doesn't have a size known at compile-time | = help: the trait `Sized` is not implemented for `str` +note: required by an implicit `Sized` bound in `Vec` + --> $SRC_DIR/alloc/src/vec/mod.rs:LL:COL = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` error: aborting due to 4 previous errors diff --git a/tests/ui/wf/wf-trait-fn-arg.next.stderr b/tests/ui/wf/wf-trait-fn-arg.next.stderr index c55dc5c8a12..d5dd36fad6d 100644 --- a/tests/ui/wf/wf-trait-fn-arg.next.stderr +++ b/tests/ui/wf/wf-trait-fn-arg.next.stderr @@ -4,6 +4,11 @@ error[E0277]: the trait bound `Self: Eq` is not satisfied LL | fn bar(&self, x: &Bar<Self>); | ^^^^^^^^^ the trait `Eq` is not implemented for `Self` | +note: required by a bound in `Bar` + --> $DIR/wf-trait-fn-arg.rs:11:15 + | +LL | struct Bar<T: Eq + ?Sized> { + | ^^ required by this bound in `Bar` help: consider further restricting `Self` | LL | fn bar(&self, x: &Bar<Self>) where Self: Eq; diff --git a/tests/ui/wf/wf-trait-fn-ret.next.stderr b/tests/ui/wf/wf-trait-fn-ret.next.stderr index b3dca17672d..0ad786c2fd5 100644 --- a/tests/ui/wf/wf-trait-fn-ret.next.stderr +++ b/tests/ui/wf/wf-trait-fn-ret.next.stderr @@ -4,6 +4,11 @@ error[E0277]: the trait bound `Self: Eq` is not satisfied LL | fn bar(&self) -> &Bar<Self>; | ^^^^^^^^^ the trait `Eq` is not implemented for `Self` | +note: required by a bound in `Bar` + --> $DIR/wf-trait-fn-ret.rs:10:15 + | +LL | struct Bar<T: Eq + ?Sized> { + | ^^ required by this bound in `Bar` help: consider further restricting `Self` | LL | fn bar(&self) -> &Bar<Self> where Self: Eq; diff --git a/tests/ui/wf/wf-trait-fn-where-clause.next.stderr b/tests/ui/wf/wf-trait-fn-where-clause.next.stderr index 8c8a5fa3e70..db5454d0f3c 100644 --- a/tests/ui/wf/wf-trait-fn-where-clause.next.stderr +++ b/tests/ui/wf/wf-trait-fn-where-clause.next.stderr @@ -4,6 +4,11 @@ error[E0277]: the trait bound `Self: Eq` is not satisfied LL | Bar<Self>: Copy; | ^^^^ the trait `Eq` is not implemented for `Self` | +note: required by a bound in `Bar` + --> $DIR/wf-trait-fn-where-clause.rs:10:15 + | +LL | struct Bar<T: Eq + ?Sized> { + | ^^ required by this bound in `Bar` help: consider further restricting `Self` | LL | Bar<Self>: Copy, Self: Eq; |