diff options
Diffstat (limited to 'compiler/typecheck/TcValidity.hs')
| -rw-r--r-- | compiler/typecheck/TcValidity.hs | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/compiler/typecheck/TcValidity.hs b/compiler/typecheck/TcValidity.hs index eaec2dbd2f..307ec6d0c5 100644 --- a/compiler/typecheck/TcValidity.hs +++ b/compiler/typecheck/TcValidity.hs @@ -232,6 +232,7 @@ wantAmbiguityCheck ctxt GhciCtxt {} -> False TySynCtxt {} -> False TypeAppCtxt -> False + StandaloneKindSigCtxt{} -> False _ -> True checkUserTypeError :: Type -> TcM () @@ -280,6 +281,10 @@ In a few places we do not want to check a user-specified type for ambiguity f @ty No need to check ty for ambiguity +* StandaloneKindSigCtxt: type T :: ksig + Kinds need a different ambiguity check than types, and the currently + implemented check is only good for types. See #14419, in particular + https://gitlab.haskell.org/ghc/ghc/issues/14419#note_160844 ************************************************************************ * * @@ -343,6 +348,7 @@ checkValidType ctxt ty ExprSigCtxt -> rank1 KindSigCtxt -> rank1 + StandaloneKindSigCtxt{} -> rank1 TypeAppCtxt | impred_flag -> ArbitraryRank | otherwise -> tyConArgMonoType -- Normally, ImpredicativeTypes is handled in check_arg_type, @@ -463,6 +469,7 @@ allConstraintsAllowed (TyVarBndrKindCtxt {}) = False allConstraintsAllowed (DataKindCtxt {}) = False allConstraintsAllowed (TySynKindCtxt {}) = False allConstraintsAllowed (TyFamResKindCtxt {}) = False +allConstraintsAllowed (StandaloneKindSigCtxt {}) = False allConstraintsAllowed _ = True -- | Returns 'True' if the supplied 'UserTypeCtxt' is unambiguously not the @@ -482,6 +489,7 @@ allConstraintsAllowed _ = True vdqAllowed :: UserTypeCtxt -> Bool -- Currently allowed in the kinds of types... vdqAllowed (KindSigCtxt {}) = True +vdqAllowed (StandaloneKindSigCtxt {}) = True vdqAllowed (TySynCtxt {}) = True vdqAllowed (ThBrackCtxt {}) = True vdqAllowed (GhciCtxt {}) = True @@ -1329,6 +1337,7 @@ okIPCtxt (TySynCtxt {}) = True -- e.g. type Blah = ?x::Int -- #11466 okIPCtxt (KindSigCtxt {}) = False +okIPCtxt (StandaloneKindSigCtxt {}) = False okIPCtxt (ClassSCCtxt {}) = False okIPCtxt (InstDeclCtxt {}) = False okIPCtxt (SpecInstCtxt {}) = False @@ -2149,7 +2158,7 @@ checkFamPatBinders fam_tc qtvs pats rhs -- data T = MkT (forall (a::k). blah) -- data family D Int = MkD (forall (a::k). blah) -- In both cases, 'k' is not bound on the LHS, but is used on the RHS - -- We catch the former in kcLHsQTyVars, and the latter right here + -- We catch the former in kcDeclHeader, and the latter right here -- See Note [Check type-family instance binders] ; check_tvs bad_rhs_tvs (text "mentioned in the RHS") (text "bound on the LHS of") |