Signature type variables must not be instantiated with tycons

[ghc-hetmet.git] / compiler / typecheck / TcSimplify.lhs

diff --git a/compiler/typecheck/TcSimplify.lhs b/compiler/typecheck/TcSimplify.lhs
index 95250f8..a59a51d 100644 (file)
--- a/compiler/typecheck/TcSimplify.lhs
+++ b/compiler/typecheck/TcSimplify.lhs
@@ -2280,7 +2280,7 @@ disambiguate extended_defaulting insts
 
    defaultable_group :: [(Inst,Class,TcTyVar)] -> Bool
    defaultable_group ds@((_,_,tv):_)
-       =  not (isImmutableTyVar tv)    -- Note [Avoiding spurious errors]
+       =  isTyConableTyVar tv  -- Note [Avoiding spurious errors]
        && not (tv `elemVarSet` bad_tvs)
        && defaultable_classes [c | (_,c,_) <- ds]
    defaultable_group [] = panic "defaultable_group"