diff --git a/src/librustc/infer/error_reporting/mod.rs b/src/librustc/infer/error_reporting/mod.rs index 5883be6e2688..684e799b4031 100644 --- a/src/librustc/infer/error_reporting/mod.rs +++ b/src/librustc/infer/error_reporting/mod.rs @@ -55,7 +55,7 @@ use crate::hir::def_id::DefId; use crate::hir::Node; use crate::infer::opaque_types; use crate::middle::region; -use crate::traits::{ObligationCause, ObligationCauseCode}; +use crate::traits::{MatchExpressionArmCause, ObligationCause, ObligationCauseCode}; use crate::ty::error::TypeError; use crate::ty::{self, subst::{Subst, SubstsRef}, Region, Ty, TyCtxt, TypeFoldable}; use errors::{Applicability, DiagnosticBuilder, DiagnosticStyledString}; @@ -624,13 +624,13 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { } } } - ObligationCauseCode::MatchExpressionArm { + ObligationCauseCode::MatchExpressionArm(box MatchExpressionArmCause { source, ref prior_arms, last_ty, discrim_hir_id, .. - } => match source { + }) => match source { hir::MatchSource::IfLetDesugar { .. } => { let msg = "`if let` arms have incompatible types"; err.span_label(cause.span, msg); @@ -1622,13 +1622,15 @@ impl<'tcx> ObligationCause<'tcx> { use crate::traits::ObligationCauseCode::*; match self.code { CompareImplMethodObligation { .. } => Error0308("method not compatible with trait"), - MatchExpressionArm { source, .. } => Error0308(match source { - hir::MatchSource::IfLetDesugar { .. } => "`if let` arms have incompatible types", - hir::MatchSource::TryDesugar => { - "try expression alternatives have incompatible types" - } - _ => "match arms have incompatible types", - }), + MatchExpressionArm(box MatchExpressionArmCause { source, .. }) => + Error0308(match source { + hir::MatchSource::IfLetDesugar { .. } => + "`if let` arms have incompatible types", + hir::MatchSource::TryDesugar => { + "try expression alternatives have incompatible types" + } + _ => "match arms have incompatible types", + }), IfExpression { .. } => Error0308("if and else have incompatible types"), IfExpressionWithNoElse => Error0317("if may be missing an else clause"), MainFunctionType => Error0580("main function has wrong type"), @@ -1656,7 +1658,7 @@ impl<'tcx> ObligationCause<'tcx> { match self.code { CompareImplMethodObligation { .. } => "method type is compatible with trait", ExprAssignable => "expression is assignable", - MatchExpressionArm { source, .. } => match source { + MatchExpressionArm(box MatchExpressionArmCause { source, .. }) => match source { hir::MatchSource::IfLetDesugar { .. } => "`if let` arms have compatible types", _ => "match arms have compatible types", }, diff --git a/src/librustc/traits/fulfill.rs b/src/librustc/traits/fulfill.rs index a59ea1989636..0b8de1f13d38 100644 --- a/src/librustc/traits/fulfill.rs +++ b/src/librustc/traits/fulfill.rs @@ -70,7 +70,7 @@ pub struct PendingPredicateObligation<'tcx> { // `PendingPredicateObligation` is used a lot. Make sure it doesn't unintentionally get bigger. #[cfg(target_arch = "x86_64")] -static_assert_size!(PendingPredicateObligation<'_>, 160); +static_assert_size!(PendingPredicateObligation<'_>, 144); impl<'a, 'tcx> FulfillmentContext<'tcx> { /// Creates a new fulfillment context. diff --git a/src/librustc/traits/mod.rs b/src/librustc/traits/mod.rs index f43fbbfee3e9..548fb55098af 100644 --- a/src/librustc/traits/mod.rs +++ b/src/librustc/traits/mod.rs @@ -125,7 +125,7 @@ pub type TraitObligation<'tcx> = Obligation<'tcx, ty::PolyTraitPredicate<'tcx>>; // `PredicateObligation` is used a lot. Make sure it doesn't unintentionally get bigger. #[cfg(target_arch = "x86_64")] -static_assert_size!(PredicateObligation<'_>, 136); +static_assert_size!(PredicateObligation<'_>, 120); /// The reason why we incurred this obligation; used for error reporting. #[derive(Clone, Debug, PartialEq, Eq, Hash)] @@ -151,7 +151,8 @@ impl<'tcx> ObligationCause<'tcx> { ObligationCauseCode::StartFunctionType => { tcx.sess.source_map().def_span(self.span) } - ObligationCauseCode::MatchExpressionArm { arm_span, .. } => arm_span, + ObligationCauseCode::MatchExpressionArm( + box MatchExpressionArmCause { arm_span, .. }) => arm_span, _ => self.span, } } @@ -227,13 +228,7 @@ pub enum ObligationCauseCode<'tcx> { ExprAssignable, /// Computing common supertype in the arms of a match expression - MatchExpressionArm { - arm_span: Span, - source: hir::MatchSource, - prior_arms: Vec, - last_ty: Ty<'tcx>, - discrim_hir_id: hir::HirId, - }, + MatchExpressionArm(Box>), /// Computing common supertype in the pattern guard for the arms of a match expression MatchExpressionArmPattern { span: Span, ty: Ty<'tcx> }, @@ -275,7 +270,16 @@ pub enum ObligationCauseCode<'tcx> { // `ObligationCauseCode` is used a lot. Make sure it doesn't unintentionally get bigger. #[cfg(target_arch = "x86_64")] -static_assert_size!(ObligationCauseCode<'_>, 56); +static_assert_size!(ObligationCauseCode<'_>, 40); + +#[derive(Clone, Debug, PartialEq, Eq, Hash)] +pub struct MatchExpressionArmCause<'tcx> { + pub arm_span: Span, + pub source: hir::MatchSource, + pub prior_arms: Vec, + pub last_ty: Ty<'tcx>, + pub discrim_hir_id: hir::HirId, +} #[derive(Clone, Debug, PartialEq, Eq, Hash)] pub struct DerivedObligationCause<'tcx> { diff --git a/src/librustc/traits/structural_impls.rs b/src/librustc/traits/structural_impls.rs index 05b698eb4c4e..56324baffa03 100644 --- a/src/librustc/traits/structural_impls.rs +++ b/src/librustc/traits/structural_impls.rs @@ -508,21 +508,21 @@ impl<'a, 'tcx> Lift<'tcx> for traits::ObligationCauseCode<'a> { trait_item_def_id, }), super::ExprAssignable => Some(super::ExprAssignable), - super::MatchExpressionArm { + super::MatchExpressionArm(box super::MatchExpressionArmCause { arm_span, source, ref prior_arms, last_ty, discrim_hir_id, - } => { + }) => { tcx.lift(&last_ty).map(|last_ty| { - super::MatchExpressionArm { + super::MatchExpressionArm(box super::MatchExpressionArmCause { arm_span, source, prior_arms: prior_arms.clone(), last_ty, discrim_hir_id, - } + }) }) } super::MatchExpressionArmPattern { span, ty } => { diff --git a/src/librustc_typeck/check/_match.rs b/src/librustc_typeck/check/_match.rs index 7427ae9ce8de..8ce08f523a1b 100644 --- a/src/librustc_typeck/check/_match.rs +++ b/src/librustc_typeck/check/_match.rs @@ -2,7 +2,7 @@ use crate::check::{FnCtxt, Expectation, Diverges, Needs}; use crate::check::coercion::CoerceMany; use rustc::hir::{self, ExprKind}; use rustc::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind}; -use rustc::traits::{ObligationCause, ObligationCauseCode}; +use rustc::traits::{MatchExpressionArmCause, ObligationCause, ObligationCauseCode}; use rustc::ty::Ty; use syntax_pos::Span; @@ -146,13 +146,15 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // The reason for the first arm to fail is not that the match arms diverge, // but rather that there's a prior obligation that doesn't hold. 0 => (arm_span, ObligationCauseCode::BlockTailExpression(arm.body.hir_id)), - _ => (expr.span, ObligationCauseCode::MatchExpressionArm { - arm_span, - source: match_src, - prior_arms: other_arms.clone(), - last_ty: prior_arm_ty.unwrap(), - discrim_hir_id: discrim.hir_id, - }), + _ => (expr.span, + ObligationCauseCode::MatchExpressionArm(box MatchExpressionArmCause { + arm_span, + source: match_src, + prior_arms: other_arms.clone(), + last_ty: prior_arm_ty.unwrap(), + discrim_hir_id: discrim.hir_id, + }) + ), }; let cause = self.cause(span, code); coercion.coerce(self, &cause, &arm.body, arm_ty);