diff options
Diffstat (limited to 'compiler/GHC/Tc/Validity.hs')
| -rw-r--r-- | compiler/GHC/Tc/Validity.hs | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/compiler/GHC/Tc/Validity.hs b/compiler/GHC/Tc/Validity.hs index 1a5f2f6a41..598b07b8c7 100644 --- a/compiler/GHC/Tc/Validity.hs +++ b/compiler/GHC/Tc/Validity.hs @@ -1137,7 +1137,9 @@ check_class_pred env dflags ctxt pred cls tys -- but here we want to treat them as equalities = -- Equational constraints are valid in all contexts, and -- we do not need to check e.g. for FlexibleContexts here, so just do nothing - return () + -- We used to require TypeFamilies/GADTs for equality constraints, + -- but not anymore (GHC Proposal #371) + return () | isIPClass cls = do { check_arity |