diff options
Diffstat (limited to 'compiler/GHC/Core/Unify.hs')
| -rw-r--r-- | compiler/GHC/Core/Unify.hs | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/compiler/GHC/Core/Unify.hs b/compiler/GHC/Core/Unify.hs index 3801126ba9..8eac3fbf63 100644 --- a/compiler/GHC/Core/Unify.hs +++ b/compiler/GHC/Core/Unify.hs @@ -658,9 +658,9 @@ niSubstTvSet :: TvSubstEnv -> TyCoVarSet -> TyCoVarSet -- remembering that the substitution isn't necessarily idempotent -- This is used in the occurs check, before extending the substitution niSubstTvSet tsubst tvs - = nonDetFoldUniqSet (unionVarSet . get) emptyVarSet tvs - -- It's OK to nonDetFoldUFM here because we immediately forget the - -- ordering by creating a set. + = nonDetStrictFoldUniqSet (unionVarSet . get) emptyVarSet tvs + -- It's OK to use a non-deterministic fold here because we immediately forget + -- the ordering by creating a set. where get tv | Just ty <- lookupVarEnv tsubst tv |