diff --git a/compiler/GHC/Tc/Errors/Types.hs b/compiler/GHC/Tc/Errors/Types.hs
index 6e58e6b03325514f9174c59db67fafd80063b375..a8d7c308462b51345d4f42cb72960a3fff370a99 100644
--- a/compiler/GHC/Tc/Errors/Types.hs
+++ b/compiler/GHC/Tc/Errors/Types.hs
@@ -3473,7 +3473,7 @@ data TcRnMessage where
-> ![LIdP GhcRn] -- ^ The LHS args
-> !PatSynInvalidRhsReason -- ^ The number of equation arguments
-> TcRnMessage
- {- TcRnCannotDefaultConcrete is an error occurring when a concrete
+ {-| TcRnCannotDefaultConcrete is an error occurring when a concrete
type variable cannot be defaulted.
Test cases:
diff --git a/compiler/GHC/Tc/Gen/Head.hs b/compiler/GHC/Tc/Gen/Head.hs
index d5721ff5e192a586b3893246323bc011250ea7f3..a5ad2f1733a807252277a6ef51b226ecaee610a4 100644
--- a/compiler/GHC/Tc/Gen/Head.hs
+++ b/compiler/GHC/Tc/Gen/Head.hs
@@ -883,7 +883,7 @@ tcExprWithSig expr hs_ty
loc = getLocA (dropWildCards hs_ty)
ctxt = ExprSigCtxt (lhsSigWcTypeContextSpan hs_ty)
-tcExprSig :: UserTypeCtxt -> LHsExpr GhcRn -> TcIdSigInfo -> TcM (LHsExpr GhcTc, TcType)
+tcExprSig :: UserTypeCtxt -> LHsExpr GhcRn -> TcIdSigInfo -> TcM (LHsExpr GhcTc, TcSigmaType)
tcExprSig ctxt expr (CompleteSig { sig_bndr = poly_id, sig_loc = loc })
= setSrcSpan loc $ -- Sets the location for the implication constraint
do { let poly_ty = idType poly_id
diff --git a/compiler/GHC/Tc/Solver/Monad.hs b/compiler/GHC/Tc/Solver/Monad.hs
index f3d0097f9349fefa33d4131be8f19bdc39f978f6..49699d865de9e605c7fa06fb49357eeed274cd7d 100644
--- a/compiler/GHC/Tc/Solver/Monad.hs
+++ b/compiler/GHC/Tc/Solver/Monad.hs
@@ -2119,14 +2119,17 @@ checkTouchableTyVarEq ev lhs_tv rhs
; if not (cterHasNoProblem reason) -- Failed to promote free vars
then failCheckWith reason
else
- do { let tv_info | isConcreteInfo lhs_tv_info = lhs_tv_info
- | otherwise = TauTv
- -- Make a concrete tyvar if lhs_tv is concrete
- -- e.g. alpha[2,conc] ~ Maybe (F beta[4])
- -- We want to flatten to
- -- alpha[2,conc] ~ Maybe gamma[2,conc]
- -- gamma[2,conc] ~ F beta[4]
- ; new_tv_ty <- TcM.newMetaTyVarTyWithInfo lhs_tv_lvl tv_info fam_app_kind
+ do { new_tv_ty <-
+ case lhs_tv_info of
+ ConcreteTv conc_info ->
+ -- Make a concrete tyvar if lhs_tv is concrete
+ -- e.g. alpha[2,conc] ~ Maybe (F beta[4])
+ -- We want to flatten to
+ -- alpha[2,conc] ~ Maybe gamma[2,conc]
+ -- gamma[2,conc] ~ F beta[4]
+ TcM.newConcreteTyVarTyAtLevel conc_info lhs_tv_lvl fam_app_kind
+ _ -> TcM.newMetaTyVarTyAtLevel lhs_tv_lvl fam_app_kind
+
; let pty = mkPrimEqPredRole Nominal fam_app new_tv_ty
; hole <- TcM.newCoercionHole pty
; let new_ev = CtWanted { ctev_pred = pty
diff --git a/compiler/GHC/Tc/Utils/Concrete.hs b/compiler/GHC/Tc/Utils/Concrete.hs
index fe0f261005ea44c7896acd0cc16c123d53a2699d..a07401ec74a87f0acacfa1bf8dcc2c863c21a9c5 100644
--- a/compiler/GHC/Tc/Utils/Concrete.hs
+++ b/compiler/GHC/Tc/Utils/Concrete.hs
@@ -8,9 +8,6 @@ module GHC.Tc.Utils.Concrete
( -- * Ensuring that a type has a fixed runtime representation
hasFixedRuntimeRep
, hasFixedRuntimeRep_syntactic
-
- -- * Making a type concrete
- , makeTypeConcrete
)
where
diff --git a/compiler/GHC/Tc/Utils/TcMType.hs b/compiler/GHC/Tc/Utils/TcMType.hs
index b4971210fd9e4fe5f3387691f84f2d9c6ba9508a..873ff2979a0e7fe7b69ec8f17500c5d0026f43b1 100644
--- a/compiler/GHC/Tc/Utils/TcMType.hs
+++ b/compiler/GHC/Tc/Utils/TcMType.hs
@@ -1,4 +1,5 @@
{-# LANGUAGE MultiWayIf #-}
+{-# LANGUAGE RecursiveDo #-}
{-# LANGUAGE TupleSections #-}
{-# OPTIONS_GHC -Wno-incomplete-record-updates #-}
@@ -24,7 +25,7 @@ module GHC.Tc.Utils.TcMType (
newOpenFlexiTyVar, newOpenFlexiTyVarTy, newOpenTypeKind,
newOpenBoxedTypeKind,
newMetaKindVar, newMetaKindVars,
- newMetaTyVarTyAtLevel, newMetaTyVarTyWithInfo,
+ newMetaTyVarTyAtLevel, newConcreteTyVarTyAtLevel,
newAnonMetaTyVar, newConcreteTyVar,
cloneMetaTyVar, cloneMetaTyVarWithInfo,
newCycleBreakerTyVar,
@@ -482,7 +483,16 @@ newInferExpType :: TcM ExpType
newInferExpType = new_inferExpType Nothing
newInferExpTypeFRR :: FixedRuntimeRepContext -> TcM ExpTypeFRR
-newInferExpTypeFRR frr_orig = new_inferExpType (Just frr_orig)
+newInferExpTypeFRR frr_orig
+ = do { th_stage <- getStage
+ ; if
+ -- See [Wrinkle: Typed Template Haskell]
+ -- in Note [hasFixedRuntimeRep] in GHC.Tc.Utils.Concrete.
+ | Brack _ (TcPending {}) <- th_stage
+ -> new_inferExpType Nothing
+
+ | otherwise
+ -> new_inferExpType (Just frr_orig) }
new_inferExpType :: Maybe FixedRuntimeRepContext -> TcM ExpType
new_inferExpType mb_frr_orig
@@ -538,20 +548,28 @@ expTypeToType (Infer inf_res) = inferResultToType inf_res
inferResultToType :: InferResult -> TcM Type
inferResultToType (IR { ir_uniq = u, ir_lvl = tc_lvl
- , ir_ref = ref })
+ , ir_ref = ref
+ , ir_frr = mb_frr })
= do { mb_inferred_ty <- readTcRef ref
; tau <- case mb_inferred_ty of
Just ty -> do { ensureMonoType ty
-- See Note [inferResultToType]
; return ty }
- Nothing -> do { rr <- newMetaTyVarTyAtLevel tc_lvl runtimeRepTy
- ; tau <- newMetaTyVarTyAtLevel tc_lvl (mkTYPEapp rr)
- -- See Note [TcLevel of ExpType]
+ Nothing -> do { tau <- new_meta
; writeMutVar ref (Just tau)
; return tau }
; traceTc "Forcing ExpType to be monomorphic:"
(ppr u <+> text ":=" <+> ppr tau)
; return tau }
+ where
+ -- See Note [TcLevel of ExpType]
+ new_meta = case mb_frr of
+ Nothing -> do { rr <- newMetaTyVarTyAtLevel tc_lvl runtimeRepTy
+ ; newMetaTyVarTyAtLevel tc_lvl (mkTYPEapp rr) }
+ Just frr -> mdo { rr <- newConcreteTyVarTyAtLevel conc_orig tc_lvl runtimeRepTy
+ ; tau <- newMetaTyVarTyAtLevel tc_lvl (mkTYPEapp rr)
+ ; let conc_orig = ConcreteFRR $ FixedRuntimeRepOrigin tau frr
+ ; return tau }
{- Note [inferResultToType]
~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -874,6 +892,13 @@ newTauTvDetailsAtLevel tclvl
, mtv_ref = ref
, mtv_tclvl = tclvl }) }
+newConcreteTvDetailsAtLevel :: ConcreteTvOrigin -> TcLevel -> TcM TcTyVarDetails
+newConcreteTvDetailsAtLevel conc_orig tclvl
+ = do { ref <- newMutVar Flexi
+ ; return (MetaTv { mtv_info = ConcreteTv conc_orig
+ , mtv_ref = ref
+ , mtv_tclvl = tclvl }) }
+
cloneMetaTyVar :: TcTyVar -> TcM TcTyVar
cloneMetaTyVar tv
= assert (isTcTyVar tv) $
@@ -931,7 +956,7 @@ isUnfilledMetaTyVar tv
--------------------
-- Works with both type and kind variables
-writeMetaTyVar :: TcTyVar -> TcType -> TcM ()
+writeMetaTyVar :: HasDebugCallStack => TcTyVar -> TcType -> TcM ()
-- Write into a currently-empty MetaTyVar
writeMetaTyVar tyvar ty
@@ -949,7 +974,7 @@ writeMetaTyVar tyvar ty
= massertPpr False (text "Writing to non-meta tyvar" <+> ppr tyvar)
--------------------
-writeMetaTyVarRef :: TcTyVar -> TcRef MetaDetails -> TcType -> TcM ()
+writeMetaTyVarRef :: HasDebugCallStack => TcTyVar -> TcRef MetaDetails -> TcType -> TcM ()
-- Here the tyvar is for error checking only;
-- the ref cell must be for the same tyvar
writeMetaTyVarRef tyvar ref ty
@@ -1114,13 +1139,10 @@ newMetaTyVarTyAtLevel tc_lvl kind
; name <- newMetaTyVarName (fsLit "p")
; return (mkTyVarTy (mkTcTyVar name kind details)) }
-newMetaTyVarTyWithInfo :: TcLevel -> MetaInfo -> TcKind -> TcM TcType
-newMetaTyVarTyWithInfo tc_lvl info kind
- = do { ref <- newMutVar Flexi
- ; let details = MetaTv { mtv_info = info
- , mtv_ref = ref
- , mtv_tclvl = tc_lvl }
- ; name <- newMetaTyVarName (fsLit "p")
+newConcreteTyVarTyAtLevel :: ConcreteTvOrigin -> TcLevel -> TcKind -> TcM TcType
+newConcreteTyVarTyAtLevel conc_orig tc_lvl kind
+ = do { details <- newConcreteTvDetailsAtLevel conc_orig tc_lvl
+ ; name <- newMetaTyVarName (fsLit "c")
; return (mkTyVarTy (mkTcTyVar name kind details)) }
{- *********************************************************************
@@ -2258,7 +2280,7 @@ a \/\a in the final result but all the occurrences of a will be zonked to ()
* *
********************************************************************* -}
-promoteMetaTyVarTo :: TcLevel -> TcTyVar -> TcM Bool
+promoteMetaTyVarTo :: HasDebugCallStack => TcLevel -> TcTyVar -> TcM Bool
-- When we float a constraint out of an implication we must restore
-- invariant (WantedInv) in Note [TcLevel invariants] in GHC.Tc.Utils.TcType
-- Return True <=> we did some promotion
@@ -2276,7 +2298,7 @@ promoteMetaTyVarTo tclvl tv
= return False
-- Returns whether or not *any* tyvar is defaulted
-promoteTyVarSet :: TcTyVarSet -> TcM Bool
+promoteTyVarSet :: HasDebugCallStack => TcTyVarSet -> TcM Bool
promoteTyVarSet tvs
= do { tclvl <- getTcLevel
; bools <- mapM (promoteMetaTyVarTo tclvl) $
diff --git a/compiler/GHC/Tc/Utils/Zonk.hs b/compiler/GHC/Tc/Utils/Zonk.hs
index 7a2c0de793f6ada90a0a762c770a6f55c38f0092..aa2ffa8baeb5ccb073af5ca74f14e0752876ed07 100644
--- a/compiler/GHC/Tc/Utils/Zonk.hs
+++ b/compiler/GHC/Tc/Utils/Zonk.hs
@@ -1738,7 +1738,7 @@ change. But in some cases it makes a HUGE difference: see test
T9198 and #19668. So yes, it seems worth it.
-}
-zonkTyVarOcc :: ZonkEnv -> TcTyVar -> TcM Type
+zonkTyVarOcc :: HasDebugCallStack => ZonkEnv -> TcTyVar -> TcM Type
zonkTyVarOcc env@(ZonkEnv { ze_flexi = flexi
, ze_tv_env = tv_env
, ze_meta_tv_env = mtv_env_ref }) tv
diff --git a/testsuite/tests/rep-poly/RepPolyInferPatBind.stderr b/testsuite/tests/rep-poly/RepPolyInferPatBind.stderr
index a9643f4b73d7aeb9e39b82537909fbf6379900ba..b85e0be15ee4ea18b884286871f24208e01bfe5f 100644
--- a/testsuite/tests/rep-poly/RepPolyInferPatBind.stderr
+++ b/testsuite/tests/rep-poly/RepPolyInferPatBind.stderr
@@ -8,7 +8,7 @@ RepPolyInferPatBind.hs:21:2: error: [GHC-55287]
• The pattern binding does not have a fixed runtime representation.
Its type is:
T :: TYPE R
- Cannot unify ‘R’ with the type variable ‘p0’
+ Cannot unify ‘R’ with the type variable ‘c0’
because it is not a concrete ‘RuntimeRep’.
• When checking that the pattern signature: T
fits the type of its context: T
diff --git a/testsuite/tests/rep-poly/RepPolyInferPatSyn.stderr b/testsuite/tests/rep-poly/RepPolyInferPatSyn.stderr
index 4515832b216754f562c8e6eb58d1686348770403..a0eb6a6916e550c55a90f00378337ffca25d0144 100644
--- a/testsuite/tests/rep-poly/RepPolyInferPatSyn.stderr
+++ b/testsuite/tests/rep-poly/RepPolyInferPatSyn.stderr
@@ -4,7 +4,7 @@ RepPolyInferPatSyn.hs:22:16: error: [GHC-55287]
does not have a fixed runtime representation.
Its type is:
T :: TYPE R
- Cannot unify ‘R’ with the type variable ‘p0’
+ Cannot unify ‘R’ with the type variable ‘c0’
because it is not a concrete ‘RuntimeRep’.
• When checking that the pattern signature: T
fits the type of its context: T
diff --git a/testsuite/tests/rep-poly/RepPolyPatBind.stderr b/testsuite/tests/rep-poly/RepPolyPatBind.stderr
index 40637215feea0fe943cad74e36953d54dcef4f96..fca59b97773d6297ba989f5fbb316c6dac87f927 100644
--- a/testsuite/tests/rep-poly/RepPolyPatBind.stderr
+++ b/testsuite/tests/rep-poly/RepPolyPatBind.stderr
@@ -1,4 +1,20 @@
+RepPolyPatBind.hs:18:5: error: [GHC-55287]
+ • The pattern binding does not have a fixed runtime representation.
+ Its type is:
+ p0 :: TYPE c0
+ Cannot unify ‘TupleRep [rep, rep]’ with the type variable ‘c0’
+ because it is not a concrete ‘RuntimeRep’.
+ • In the pattern: (# x, y #)
+ In a pattern binding: (# x, y #) = undefined
+ In the expression:
+ let
+ x, y :: a
+ (# x, y #) = undefined
+ in x
+ • Relevant bindings include
+ foo :: () -> a (bound at RepPolyPatBind.hs:15:1)
+
RepPolyPatBind.hs:18:5: error: [GHC-55287]
• • The binder ‘y’ does not have a fixed runtime representation.
Its type is:
diff --git a/testsuite/tests/rep-poly/T23154.hs b/testsuite/tests/rep-poly/T23154.hs
new file mode 100644
index 0000000000000000000000000000000000000000..b0048e441f51770299f3aa5edfa0f8e0c6b12fa8
--- /dev/null
+++ b/testsuite/tests/rep-poly/T23154.hs
@@ -0,0 +1,7 @@
+{-# LANGUAGE PartialTypeSignatures #-}
+
+module T23154 where
+
+import GHC.Exts
+
+f x = x :: (_ :: (TYPE (_ _)))
diff --git a/testsuite/tests/rep-poly/T23154.stderr b/testsuite/tests/rep-poly/T23154.stderr
new file mode 100644
index 0000000000000000000000000000000000000000..46d416a0d0b5a3813ce9fd8b2e5862f7e686c764
--- /dev/null
+++ b/testsuite/tests/rep-poly/T23154.stderr
@@ -0,0 +1,10 @@
+
+T23154.hs:7:1: error: [GHC-52083]
+ The first pattern in the equation for ‘f’
+ cannot be assigned a fixed runtime representation, not even by defaulting.
+ Suggested fix: Add a type signature.
+
+T23154.hs:7:1: error: [GHC-52083]
+ The first pattern in the equation for ‘f’
+ cannot be assigned a fixed runtime representation, not even by defaulting.
+ Suggested fix: Add a type signature.
diff --git a/testsuite/tests/rep-poly/all.T b/testsuite/tests/rep-poly/all.T
index a05a6bb7e5d94babf2c302ffd31a1db8bc065557..0be5b954af0b4ba64f08b4b0a7e29b49ef779a92 100644
--- a/testsuite/tests/rep-poly/all.T
+++ b/testsuite/tests/rep-poly/all.T
@@ -117,3 +117,4 @@ test('T21650_b', normal, compile_fail, ['-Wno-deprecated-flags']) ##
test('T23051', normal, compile_fail, [''])
test('T23153', normal, compile_fail, [''])
+test('T23154', normal, compile_fail, [''])
diff --git a/testsuite/tests/typecheck/should_fail/VtaFail.stderr b/testsuite/tests/typecheck/should_fail/VtaFail.stderr
index 4d01d8b8bbcf17142739547ec5117d0c87255a16..925189c0fcbd5b9805fe6f67df8c5636800c94b7 100644
--- a/testsuite/tests/typecheck/should_fail/VtaFail.stderr
+++ b/testsuite/tests/typecheck/should_fail/VtaFail.stderr
@@ -7,7 +7,7 @@ VtaFail.hs:7:16: error: [GHC-95781]
answer_nosig = pairup_nosig @Int @Bool 5 True
VtaFail.hs:14:17: error: [GHC-95781]
- • Cannot apply expression of type ‘p1 -> p1’
+ • Cannot apply expression of type ‘p0 -> p0’
to a visible type argument ‘Int’
• In the expression: (\ x -> x) @Int 12
In an equation for ‘answer_lambda’: