diff options
Diffstat (limited to 'compiler/GHC/Tc/Validity.hs')
| -rw-r--r-- | compiler/GHC/Tc/Validity.hs | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/compiler/GHC/Tc/Validity.hs b/compiler/GHC/Tc/Validity.hs index 18474d41b1..1a5f2f6a41 100644 --- a/compiler/GHC/Tc/Validity.hs +++ b/compiler/GHC/Tc/Validity.hs @@ -1788,7 +1788,6 @@ checkInstTermination theta head_pred check foralld_tvs pred = case classifyPredType pred of EqPred {} -> return () -- See #4200. - SpecialPred {} -> return () IrredPred {} -> check2 foralld_tvs pred (sizeType pred) ClassPred cls tys | isTerminatingClass cls @@ -1807,6 +1806,10 @@ checkInstTermination theta head_pred -> check (foralld_tvs `extendVarSetList` tvs) head_pred' -- Termination of the quantified predicate itself is checked -- when the predicates are individually checked for validity + SpecialPred {} -> + pprPanic "checkInstTermination: unexpected special constraint" $ + vcat [ text "pred:" <+> ppr pred + , text "theta:" <+> ppr theta ] check2 foralld_tvs pred pred_size | not (null bad_tvs) = failWithTc $ TcRnUnknownMessage $ mkPlainError noHints $ |