obligations: FxIndexSet<PredicateObligation<'tcx>>,
relationships: FxHashMap<ty::TyVid, ty::FoundRelationships>,
+
+ usable_in_snapshot: bool,
}
impl FulfillmentContext<'_> {
FulfillmentContext {
obligations: FxIndexSet::default(),
relationships: FxHashMap::default(),
+ usable_in_snapshot: false,
}
}
+
+ pub(crate) fn new_in_snapshot() -> Self {
+ FulfillmentContext { usable_in_snapshot: true, ..Self::new() }
+ }
}
impl<'tcx> TraitEngine<'tcx> for FulfillmentContext<'tcx> {
infcx: &InferCtxt<'tcx>,
obligation: PredicateObligation<'tcx>,
) {
- assert!(!infcx.is_in_snapshot());
+ if !self.usable_in_snapshot {
+ assert!(!infcx.is_in_snapshot());
+ }
let obligation = infcx.resolve_vars_if_possible(obligation);
super::relationships::update(self, infcx, &obligation);
}
fn select_where_possible(&mut self, infcx: &InferCtxt<'tcx>) -> Vec<FulfillmentError<'tcx>> {
- assert!(!infcx.is_in_snapshot());
+ if !self.usable_in_snapshot {
+ assert!(!infcx.is_in_snapshot());
+ }
let mut errors = Vec::new();
let mut next_round = FxIndexSet::default();