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merged 3 commits into from
Sep 28, 2024
Merged

Allow instantiating object trait binder when upcasting #130866

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d4ee408
Check allow instantiating object trait binder when upcasting and in n…
compiler-errors Sep 25, 2024
4fb097a
Instantiate binders when checking supertrait upcasting
compiler-errors Sep 27, 2024
d753aba
Get rid of a_is_expected from ToTrace
compiler-errors Sep 27, 2024
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164 changes: 54 additions & 110 deletions compiler/rustc_infer/src/infer/at.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -92,12 +92,7 @@ impl<'tcx> InferCtxt<'tcx> {
}

pub trait ToTrace<'tcx>: Relate<TyCtxt<'tcx>> + Copy {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx>;
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx>;
}

impl<'a, 'tcx> At<'a, 'tcx> {
Expand All @@ -116,7 +111,7 @@ impl<'a, 'tcx> At<'a, 'tcx> {
{
let mut fields = CombineFields::new(
self.infcx,
ToTrace::to_trace(self.cause, true, expected, actual),
ToTrace::to_trace(self.cause, expected, actual),
self.param_env,
define_opaque_types,
);
Expand All @@ -136,7 +131,7 @@ impl<'a, 'tcx> At<'a, 'tcx> {
{
let mut fields = CombineFields::new(
self.infcx,
ToTrace::to_trace(self.cause, true, expected, actual),
ToTrace::to_trace(self.cause, expected, actual),
self.param_env,
define_opaque_types,
);
Expand All @@ -154,12 +149,26 @@ impl<'a, 'tcx> At<'a, 'tcx> {
where
T: ToTrace<'tcx>,
{
let mut fields = CombineFields::new(
self.infcx,
ToTrace::to_trace(self.cause, true, expected, actual),
self.param_env,
self.eq_trace(
define_opaque_types,
);
ToTrace::to_trace(self.cause, expected, actual),
expected,
actual,
)
}

/// Makes `expected == actual`.
pub fn eq_trace<T>(
self,
define_opaque_types: DefineOpaqueTypes,
trace: TypeTrace<'tcx>,
expected: T,
actual: T,
) -> InferResult<'tcx, ()>
where
T: Relate<TyCtxt<'tcx>>,
{
let mut fields = CombineFields::new(self.infcx, trace, self.param_env, define_opaque_types);
fields.equate(StructurallyRelateAliases::No).relate(expected, actual)?;
Ok(InferOk {
value: (),
Expand Down Expand Up @@ -192,7 +201,7 @@ impl<'a, 'tcx> At<'a, 'tcx> {
assert!(self.infcx.next_trait_solver());
let mut fields = CombineFields::new(
self.infcx,
ToTrace::to_trace(self.cause, true, expected, actual),
ToTrace::to_trace(self.cause, expected, actual),
self.param_env,
DefineOpaqueTypes::Yes,
);
Expand Down Expand Up @@ -284,7 +293,7 @@ impl<'a, 'tcx> At<'a, 'tcx> {
{
let mut fields = CombineFields::new(
self.infcx,
ToTrace::to_trace(self.cause, true, expected, actual),
ToTrace::to_trace(self.cause, expected, actual),
self.param_env,
define_opaque_types,
);
Expand All @@ -306,7 +315,7 @@ impl<'a, 'tcx> At<'a, 'tcx> {
{
let mut fields = CombineFields::new(
self.infcx,
ToTrace::to_trace(self.cause, true, expected, actual),
ToTrace::to_trace(self.cause, expected, actual),
self.param_env,
define_opaque_types,
);
Expand All @@ -316,18 +325,13 @@ impl<'a, 'tcx> At<'a, 'tcx> {
}

impl<'tcx> ToTrace<'tcx> for ImplSubject<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
match (a, b) {
(ImplSubject::Trait(trait_ref_a), ImplSubject::Trait(trait_ref_b)) => {
ToTrace::to_trace(cause, a_is_expected, trait_ref_a, trait_ref_b)
ToTrace::to_trace(cause, trait_ref_a, trait_ref_b)
}
(ImplSubject::Inherent(ty_a), ImplSubject::Inherent(ty_b)) => {
ToTrace::to_trace(cause, a_is_expected, ty_a, ty_b)
ToTrace::to_trace(cause, ty_a, ty_b)
}
(ImplSubject::Trait(_), ImplSubject::Inherent(_))
| (ImplSubject::Inherent(_), ImplSubject::Trait(_)) => {
Expand All @@ -338,65 +342,45 @@ impl<'tcx> ToTrace<'tcx> for ImplSubject<'tcx> {
}

impl<'tcx> ToTrace<'tcx> for Ty<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: ValuePairs::Terms(ExpectedFound::new(a_is_expected, a.into(), b.into())),
values: ValuePairs::Terms(ExpectedFound::new(true, a.into(), b.into())),
}
}
}

impl<'tcx> ToTrace<'tcx> for ty::Region<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: ValuePairs::Regions(ExpectedFound::new(a_is_expected, a, b)),
values: ValuePairs::Regions(ExpectedFound::new(true, a, b)),
}
}
}

impl<'tcx> ToTrace<'tcx> for Const<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: ValuePairs::Terms(ExpectedFound::new(a_is_expected, a.into(), b.into())),
values: ValuePairs::Terms(ExpectedFound::new(true, a.into(), b.into())),
}
}
}

impl<'tcx> ToTrace<'tcx> for ty::GenericArg<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: match (a.unpack(), b.unpack()) {
(GenericArgKind::Lifetime(a), GenericArgKind::Lifetime(b)) => {
ValuePairs::Regions(ExpectedFound::new(a_is_expected, a, b))
ValuePairs::Regions(ExpectedFound::new(true, a, b))
}
(GenericArgKind::Type(a), GenericArgKind::Type(b)) => {
ValuePairs::Terms(ExpectedFound::new(a_is_expected, a.into(), b.into()))
ValuePairs::Terms(ExpectedFound::new(true, a.into(), b.into()))
}
(GenericArgKind::Const(a), GenericArgKind::Const(b)) => {
ValuePairs::Terms(ExpectedFound::new(a_is_expected, a.into(), b.into()))
ValuePairs::Terms(ExpectedFound::new(true, a.into(), b.into()))
}

(
Expand All @@ -419,72 +403,47 @@ impl<'tcx> ToTrace<'tcx> for ty::GenericArg<'tcx> {
}

impl<'tcx> ToTrace<'tcx> for ty::Term<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: ValuePairs::Terms(ExpectedFound::new(a_is_expected, a, b)),
values: ValuePairs::Terms(ExpectedFound::new(true, a, b)),
}
}
}

impl<'tcx> ToTrace<'tcx> for ty::TraitRef<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: ValuePairs::TraitRefs(ExpectedFound::new(a_is_expected, a, b)),
values: ValuePairs::TraitRefs(ExpectedFound::new(true, a, b)),
}
}
}

impl<'tcx> ToTrace<'tcx> for ty::AliasTy<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: ValuePairs::Aliases(ExpectedFound::new(a_is_expected, a.into(), b.into())),
values: ValuePairs::Aliases(ExpectedFound::new(true, a.into(), b.into())),
}
}
}

impl<'tcx> ToTrace<'tcx> for ty::AliasTerm<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: ValuePairs::Aliases(ExpectedFound::new(a_is_expected, a, b)),
values: ValuePairs::Aliases(ExpectedFound::new(true, a, b)),
}
}
}

impl<'tcx> ToTrace<'tcx> for ty::FnSig<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: ValuePairs::PolySigs(ExpectedFound::new(
a_is_expected,
true,
ty::Binder::dummy(a),
ty::Binder::dummy(b),
)),
Expand All @@ -493,43 +452,28 @@ impl<'tcx> ToTrace<'tcx> for ty::FnSig<'tcx> {
}

impl<'tcx> ToTrace<'tcx> for ty::PolyFnSig<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: ValuePairs::PolySigs(ExpectedFound::new(a_is_expected, a, b)),
values: ValuePairs::PolySigs(ExpectedFound::new(true, a, b)),
}
}
}

impl<'tcx> ToTrace<'tcx> for ty::PolyExistentialTraitRef<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: ValuePairs::ExistentialTraitRef(ExpectedFound::new(a_is_expected, a, b)),
values: ValuePairs::ExistentialTraitRef(ExpectedFound::new(true, a, b)),
}
}
}

impl<'tcx> ToTrace<'tcx> for ty::PolyExistentialProjection<'tcx> {
fn to_trace(
cause: &ObligationCause<'tcx>,
a_is_expected: bool,
a: Self,
b: Self,
) -> TypeTrace<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>, a: Self, b: Self) -> TypeTrace<'tcx> {
TypeTrace {
cause: cause.clone(),
values: ValuePairs::ExistentialProjection(ExpectedFound::new(a_is_expected, a, b)),
values: ValuePairs::ExistentialProjection(ExpectedFound::new(true, a, b)),
}
}
}
16 changes: 9 additions & 7 deletions compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -448,10 +448,10 @@ where
}
}
} else {
self.delegate.enter_forall(kind, |kind| {
let goal = goal.with(self.cx(), ty::Binder::dummy(kind));
self.add_goal(GoalSource::InstantiateHigherRanked, goal);
self.evaluate_added_goals_and_make_canonical_response(Certainty::Yes)
self.enter_forall(kind, |ecx, kind| {
let goal = goal.with(ecx.cx(), ty::Binder::dummy(kind));
ecx.add_goal(GoalSource::InstantiateHigherRanked, goal);
ecx.evaluate_added_goals_and_make_canonical_response(Certainty::Yes)
})
}
}
Expand Down Expand Up @@ -840,12 +840,14 @@ where
self.delegate.instantiate_binder_with_infer(value)
}

/// `enter_forall`, but takes `&mut self` and passes it back through the
/// callback since it can't be aliased during the call.
pub(super) fn enter_forall<T: TypeFoldable<I> + Copy, U>(
&self,
&mut self,
value: ty::Binder<I, T>,
f: impl FnOnce(T) -> U,
f: impl FnOnce(&mut Self, T) -> U,
) -> U {
self.delegate.enter_forall(value, f)
self.delegate.enter_forall(value, |value| f(self, value))
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given that enter_forall is only used once, maybe it's easier to always use enter_forall_mut by modifying the signature of neter_forall.

While you're at it, change fn compute_goal to use self.enter_forall from self.delegate.enter_forall 😁

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I remember there being a specific problem where we had an infectious &mut self that ended up changing quite a lot if we did this

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nvm, just needed to move an arg lol

}

pub(super) fn resolve_vars_if_possible<T>(&self, value: T) -> T
Expand Down
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