bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

Rollup merge of #124936 - lcnr:cool-beans, r=compiler-errors

Browse source 
analyse visitor: build proof tree in probe

see inline comments

fixes #124791
fixes #124702

r? ```@compiler-errors```
This commit is contained in:
Matthias Krüger 2024-05-10 07:30:21 +02:00 • committed by GitHub
commit 43ddd1d963
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
8 changed files with 113 additions and 34 deletions
Download patch file Download diff file Expand all files Collapse all files

1
compiler/rustc_trait_selection/src/solve/eval_ctxt/canonical.rs
View file

@ -409,6 +409,7 @@ pub(in crate::solve) fn make_canonical_state<'tcx, T: TypeFoldable<TyCtxt<'tcx>>
/// This currently assumes that unifying the var values trivially succeeds.
/// Adding any inference constraints which weren't present when originally
/// computing the canonical query can result in bugs.
#[instrument(level = "debug", skip(infcx, span, param_env))]
pub(in crate::solve) fn instantiate_canonical_state<'tcx, T: TypeFoldable<TyCtxt<'tcx>>>(
infcx: &InferCtxt<'tcx>,
span: Span,

44
compiler/rustc_trait_selection/src/solve/inspect/analyse.rs
View file

@ -146,6 +146,11 @@ impl<'a, 'tcx> InspectCandidate<'a, 'tcx> {
/// inference constraints, and optionally the args of an impl if this candidate
/// came from a `CandidateSource::Impl`. This function modifies the state of the
/// `infcx`.
#[instrument(
level = "debug",
skip_all,
fields(goal = ?self.goal.goal, nested_goals = ?self.nested_goals)
)]
pub fn instantiate_nested_goals_and_opt_impl_args(
&self,
span: Span,
@ -213,10 +218,23 @@ impl<'a, 'tcx> InspectCandidate<'a, 'tcx> {
};
let goal =
goal.with(infcx.tcx, ty::NormalizesTo { alias, term: unconstrained_term });
let proof_tree = EvalCtxt::enter_root(infcx, GenerateProofTree::Yes, |ecx| {
ecx.evaluate_goal_raw(GoalEvaluationKind::Root, GoalSource::Misc, goal)
})
.1;
// 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(|_| {
EvalCtxt::enter_root(infcx, GenerateProofTree::Yes, |ecx| {
ecx.evaluate_goal_raw(
GoalEvaluationKind::Root,
GoalSource::Misc,
goal,
)
})
})
.1;
InspectGoal::new(
infcx,
self.goal.depth + 1,
@ -225,13 +243,17 @@ impl<'a, 'tcx> InspectCandidate<'a, 'tcx> {
source,
)
}
_ => InspectGoal::new(
infcx,
self.goal.depth + 1,
infcx.evaluate_root_goal(goal, GenerateProofTree::Yes).1.unwrap(),
None,
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)
}
})
.collect();