exprIsLambda_maybe: Unexpected lambda in case
Summary
When compiling certain files, GHC emits a "exprIsLambda_maybe: Unexpected lambda in case" message on stdout. This is not a error or warning, but (presumably) a pprTrace from https://gitlab.haskell.org/ghc/ghc/-/blob/master/compiler/GHC/Core/Opt/Arity.hs#L1797. It is unclear to me whether this is a benign message or represents an actual problem.
Steps to reproduce
Bug.hs (depends on optics-core=0.4. See below for a self-contained reproducer)
{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE OverloadedLabels #-}
{-# OPTIONS_GHC -Wall -dcore-lint #-}
module Bug (bar) where
import GHC.Generics (Generic)
import Optics.Setter
import Optics.Optic
import Optics.Label ()
data A = MkA ()
deriving Generic
data B = B {getB :: A}
deriving Generic
ba :: Setter' B A
ba = castOptic #getB
aunit :: Setter' A ()
aunit = castOptic #_MkA
bar :: Monad m => m [B]
bar = do
_ <- pure []
pure $ over (mapped %% ba) updateDefs []
where updateDefs = over aunit idCompile the above file with -O and ghc 9.2.2:
$ ghc -O -fforce-recomp Bug.hs
[1 of 1] Compiling Bug ( Bug.hs, Bug.o )
exprIsLambda_maybe: Unexpected lambda in case
\ (eta_B0 :: B) ->
$cto_a2rq
@Any
(((updateDefs_s3gG
`cast` ((N:FunArrow[0] <Curry NoIx Any>_P
; Sym (N:FunArrow[0] <Any>_P)) <A>_N <A>_N
; N:FunArrow[0] <Any>_P <A>_N <A>_N
:: FunArrow (Curry NoIx Any) A A ~R# (A -> A)))
(case eta_B0 of { B ds_d32G -> ds_d32G }))
`cast` (Sym (N:K1[0] <Type>_N <R>_P <A>_R <Any>_P)
; (Sym (N:M1[0]
<Type>_N
<S>_P
<'MetaSel
('Just "getB")
'NoSourceUnpackedness
'NoSourceStrictness
'DecidedLazy>_P
<Rec0 A>_R)
; Sym (N:M1[0]
<Type>_N
<C>_P
<'MetaCons "B" 'PrefixI 'True>_P
<M1
S
('MetaSel
('Just "getB")
'NoSourceUnpackedness
'NoSourceStrictness
'DecidedLazy)
(Rec0 A)>_R)
; Sym (N:M1[0]
<Type>_N
<D>_P
<'MetaData "B" "Bug" "main" 'False>_P
<M1
C
('MetaCons "B" 'PrefixI 'True)
(S1
('MetaSel
('Just "getB")
'NoSourceUnpackedness
'NoSourceStrictness
'DecidedLazy)
(Rec0 A))>_R)
; Sub (Sym (Rep_B[0]))) <Any>_N
:: A ~R# Rep B Any))
`ghc -v` output
$ ghc -v -O Bug.hs -fforce-recomp
Glasgow Haskell Compiler, Version 9.2.2, stage 2 booted by GHC version 8.10.7
*** initializing unit database:
Using binary package database: /nix/store/065vznbk990dd2qkdd7qyr5wfrvh52p7-ghc-9.2.2-with-packages/lib/ghc-9.2.2/package.conf.d/package.cache
package flags []
loading package database /nix/store/065vznbk990dd2qkdd7qyr5wfrvh52p7-ghc-9.2.2-with-packages/lib/ghc-9.2.2/package.conf.d
wired-in package ghc-prim mapped to ghc-prim-0.8.0
wired-in package ghc-bignum mapped to ghc-bignum-1.2
wired-in package base mapped to base-4.16.1.0
wired-in package rts mapped to rts
wired-in package template-haskell mapped to template-haskell-2.18.0.0
wired-in package ghc mapped to ghc-9.2.2
!!! initializing unit database: finished in 4.97 milliseconds, allocated 6.073 megabytes
*** initializing unit database:
package flags []
loading package database /nix/store/065vznbk990dd2qkdd7qyr5wfrvh52p7-ghc-9.2.2-with-packages/lib/ghc-9.2.2/package.conf.d
wired-in package ghc-prim mapped to ghc-prim-0.8.0
wired-in package ghc-bignum mapped to ghc-bignum-1.2
wired-in package base mapped to base-4.16.1.0
wired-in package rts mapped to rts
wired-in package template-haskell mapped to template-haskell-2.18.0.0
wired-in package ghc mapped to ghc-9.2.2
!!! initializing unit database: finished in 13.92 milliseconds, allocated 3.559 megabytes
*** Chasing dependencies:
Chasing modules from: Bug.hs
!!! Chasing dependencies: finished in 0.95 milliseconds, allocated 1.489 megabytes
Stable obj: {}
Stable BCO: {}
Ready for upsweep
[NONREC
ModSummary {
ms_hs_date = 2022-05-11 19:24:15.264209807 UTC
ms_mod = Bug,
ms_textual_imps = [(Nothing, Prelude), (Nothing, Optics.Label),
(Nothing, Optics.Optic), (Nothing, Optics.Setter),
(Nothing, GHC.Generics)]
ms_srcimps = []
} []]
*** Deleting temp files:
Deleting:
compile: input file Bug.hs
*** Checking old interface for Bug (use -ddump-hi-diffs for more details):
[1 of 1] Compiling Bug ( Bug.hs, Bug.o )
*** Parser [Bug]:
!!! Parser [Bug]: finished in 0.48 milliseconds, allocated 0.821 megabytes
*** Renamer/typechecker [Bug]:
!!! Renamer/typechecker [Bug]: finished in 124.63 milliseconds, allocated 68.782 megabytes
*** Desugar [Bug]:
Result size of Desugar (before optimization)
= {terms: 422, types: 2,528, coercions: 1,408, joins: 0/25}
*** Core Linted result of Desugar (before optimization):
Result size of Desugar (after optimization)
= {terms: 264, types: 1,677, coercions: 1,487, joins: 0/2}
*** Core Linted result of Desugar (after optimization):
!!! Desugar [Bug]: finished in 28.23 milliseconds, allocated 33.476 megabytes
*** Simplifier [Bug]:
Result size of Simplifier iteration=1
= {terms: 424, types: 2,966, coercions: 5,323, joins: 0/27}
*** Core Linted result of Simplifier:
exprIsLambda_maybe: Unexpected lambda in case
\ (eta_B0 :: B) ->
$cto_a2rq
@Any
(((updateDefs_s3gG
`cast` ((N:FunArrow[0] <Curry NoIx Any>_P
; Sym (N:FunArrow[0] <Any>_P)) <A>_N <A>_N
; N:FunArrow[0] <Any>_P <A>_N <A>_N
:: FunArrow (Curry NoIx Any) A A ~R# (A -> A)))
(case eta_B0 of { B ds_d32G -> ds_d32G }))
`cast` (Sym (N:K1[0] <Type>_N <R>_P <A>_R <Any>_P)
; (Sym (N:M1[0]
<Type>_N
<S>_P
<'MetaSel
('Just "getB")
'NoSourceUnpackedness
'NoSourceStrictness
'DecidedLazy>_P
<Rec0 A>_R)
; Sym (N:M1[0]
<Type>_N
<C>_P
<'MetaCons "B" 'PrefixI 'True>_P
<M1
S
('MetaSel
('Just "getB")
'NoSourceUnpackedness
'NoSourceStrictness
'DecidedLazy)
(Rec0 A)>_R)
; Sym (N:M1[0]
<Type>_N
<D>_P
<'MetaData "B" "Bug" "main" 'False>_P
<M1
C
('MetaCons "B" 'PrefixI 'True)
(S1
('MetaSel
('Just "getB")
'NoSourceUnpackedness
'NoSourceStrictness
'DecidedLazy)
(Rec0 A))>_R)
; Sub (Sym (Rep_B[0]))) <Any>_N
:: A ~R# Rep B Any))
Result size of Simplifier iteration=2
= {terms: 194, types: 246, coercions: 1,958, joins: 0/7}
*** Core Linted result of Simplifier:
Result size of Simplifier
= {terms: 143, types: 110, coercions: 318, joins: 0/1}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 41.63 milliseconds, allocated 61.074 megabytes
*** Specialise [Bug]:
Result size of Specialise
= {terms: 143, types: 110, coercions: 318, joins: 0/1}
*** Core Linted result of Specialise:
!!! Specialise [Bug]: finished in 0.83 milliseconds, allocated 1.323 megabytes
*** Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = False}) [Bug]:
Result size of Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = False})
= {terms: 149, types: 121, coercions: 318, joins: 0/2}
*** Core Linted result of Float out(FOS {Lam = Just 0, Consts = True, OverSatApps = False}):
!!! Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = False}) [Bug]: finished in 1.57 milliseconds, allocated 1.597 megabytes
*** Simplifier [Bug]:
Result size of Simplifier iteration=1
= {terms: 147, types: 115, coercions: 318, joins: 0/2}
*** Core Linted result of Simplifier:
Result size of Simplifier
= {terms: 147, types: 115, coercions: 318, joins: 0/2}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 3.04 milliseconds, allocated 4.197 megabytes
*** Simplifier [Bug]:
Result size of Simplifier iteration=1
= {terms: 143, types: 111, coercions: 318, joins: 0/2}
*** Core Linted result of Simplifier:
Result size of Simplifier
= {terms: 141, types: 108, coercions: 318, joins: 0/2}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 2.86 milliseconds, allocated 4.160 megabytes
*** Simplifier [Bug]:
Result size of Simplifier
= {terms: 141, types: 108, coercions: 318, joins: 0/2}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 1.42 milliseconds, allocated 2.075 megabytes
*** Float inwards [Bug]:
Result size of Float inwards
= {terms: 141, types: 108, coercions: 318, joins: 0/2}
*** Core Linted result of Float inwards:
!!! Float inwards [Bug]: finished in 0.79 milliseconds, allocated 1.285 megabytes
*** Called arity analysis [Bug]:
Result size of Called arity analysis
= {terms: 141, types: 108, coercions: 318, joins: 0/2}
*** Core Linted result of Called arity analysis:
!!! Called arity analysis [Bug]: finished in 0.79 milliseconds, allocated 1.316 megabytes
*** Simplifier [Bug]:
Result size of Simplifier
= {terms: 141, types: 108, coercions: 318, joins: 0/2}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 1.71 milliseconds, allocated 2.075 megabytes
*** Demand analysis [Bug]:
Result size of Demand analysis
= {terms: 141, types: 108, coercions: 318, joins: 0/2}
*** Core Linted result of Demand analysis:
!!! Demand analysis [Bug]: finished in 0.84 milliseconds, allocated 1.341 megabytes
*** Constructed Product Result analysis [Bug]:
Result size of Constructed Product Result analysis
= {terms: 141, types: 108, coercions: 318, joins: 0/2}
*** Core Linted result of Constructed Product Result analysis:
!!! Constructed Product Result analysis [Bug]: finished in 0.85 milliseconds, allocated 1.350 megabytes
*** Worker Wrapper binds [Bug]:
Result size of Worker Wrapper binds
= {terms: 166, types: 198, coercions: 318, joins: 0/6}
*** Core Linted result of Worker Wrapper binds:
!!! Worker Wrapper binds [Bug]: finished in 1.10 milliseconds, allocated 1.596 megabytes
*** Simplifier [Bug]:
Result size of Simplifier iteration=1
= {terms: 159, types: 189, coercions: 318, joins: 0/4}
*** Core Linted result of Simplifier:
Result size of Simplifier
= {terms: 147, types: 160, coercions: 318, joins: 0/1}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 3.56 milliseconds, allocated 4.717 megabytes
*** Exitification transformation [Bug]:
Result size of Exitification transformation
= {terms: 147, types: 160, coercions: 318, joins: 0/1}
*** Core Linted result of Exitification transformation:
!!! Exitification transformation [Bug]: finished in 0.93 milliseconds, allocated 1.384 megabytes
*** Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = True}) [Bug]:
Result size of Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = True})
= {terms: 147, types: 160, coercions: 318, joins: 0/1}
*** Core Linted result of Float out(FOS {Lam = Just 0, Consts = True, OverSatApps = True}):
!!! Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = True}) [Bug]: finished in 1.18 milliseconds, allocated 1.743 megabytes
*** Common sub-expression [Bug]:
Result size of Common sub-expression
= {terms: 147, types: 160, coercions: 318, joins: 0/1}
*** Core Linted result of Common sub-expression:
!!! Common sub-expression [Bug]: finished in 1.31 milliseconds, allocated 1.520 megabytes
*** Float inwards [Bug]:
Result size of Float inwards
= {terms: 147, types: 160, coercions: 318, joins: 0/1}
*** Core Linted result of Float inwards:
!!! Float inwards [Bug]: finished in 0.87 milliseconds, allocated 1.440 megabytes
*** Simplifier [Bug]:
Result size of Simplifier
= {terms: 147, types: 160, coercions: 318, joins: 0/1}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 1.62 milliseconds, allocated 2.308 megabytes
*** Demand analysis [Bug]:
Result size of Demand analysis
= {terms: 147, types: 160, coercions: 318, joins: 0/1}
*** Core Linted result of Demand analysis:
!!! Demand analysis [Bug]: finished in 0.97 milliseconds, allocated 1.506 megabytes
*** CoreTidy [Bug]:
Result size of Tidy Core
= {terms: 147, types: 160, coercions: 318, joins: 0/1}
*** Core Linted result of Tidy Core:
!!! CoreTidy [Bug]: finished in 1.24 milliseconds, allocated 1.757 megabytes
Created temporary directory: /tmp/nix-shell.l4CKl0/ghc3061224_0
*** CorePrep [Bug]:
Result size of CorePrep
= {terms: 159, types: 176, coercions: 318, joins: 0/3}
*** Core Linted result of CorePrep:
!!! CorePrep [Bug]: finished in 1.27 milliseconds, allocated 1.831 megabytes
*** CoreToStg [Bug]:
*** Stg2Stg:
!!! CoreToStg [Bug]: finished in 0.17 milliseconds, allocated 0.240 megabytes
*** CodeGen [Bug]:
!!! CodeGen [Bug]: finished in 6.67 milliseconds, allocated 7.047 megabytes
*** systool:as:
*** Assembler:
/nix/store/bg35nfwn6zd616facdywiysgpprfvsji-gcc-wrapper-11.3.0/bin/cc -iquote. -no-pie -fno-PIC -x assembler -c /tmp/nix-shell.l4CKl0/ghc3061224_0/ghc_2.s -o Bug.o.tmp
!!! systool:as: finished in 0.34 milliseconds, allocated 0.122 megabytes
Upsweep completely successful.
*** Deleting temp files:
Deleting: /tmp/nix-shell.l4CKl0/ghc3061224_0/ghc_1.s /tmp/nix-shell.l4CKl0/ghc3061224_0/ghc_2.s /tmp/nix-shell.l4CKl0/ghc3061224_0/ghc_3.c
Warning: deleting non-existent /tmp/nix-shell.l4CKl0/ghc3061224_0/ghc_1.s
Warning: deleting non-existent /tmp/nix-shell.l4CKl0/ghc3061224_0/ghc_3.c
link(batch): upsweep (partially) failed OR
Main.main not exported; not linking.
*** Deleting temp files:
Deleting:
*** Deleting temp dirs:
Deleting: /tmp/nix-shell.l4CKl0/ghc3061224_0To get a standalone example, I have inlined code from optics and attempted to minimise, resulting in
{-# LANGUAGE AllowAmbiguousTypes #-}
{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeApplications #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE TypeInType #-}
{-# OPTIONS_GHC -Wall -dcore-lint #-}
module Bug (bar) where
import GHC.Generics
import GHC.Exts (Constraint)
import Data.Coerce (coerce)
import Data.Kind (Type)
data A = MkA ()
deriving Generic
data B = B A
ba :: Optic A_Setter B B A A
ba = Optic $ dimap (\(B e) -> (e, B e)) (B . fst) . first' -- NB: removing fst and first' hides the message
-- NB: aunit = undefined shows error in 8.10.7 and 9.0.1 but not 9.2.1
aunit :: Optic A_Setter A A () ()
aunit = case foo (Market id Right) of
Market construct match -> Optic $ dimap match (either id construct) . undefined
where
foo :: Profunctor p => p NoIx () () -> p NoIx A A
foo = dimap from to . dimap coerce coerce
bar :: Monad m => m [B]
bar = do
_ <- pure []
pure $ over (mapped %% ba) inner []
where
-- NB: inlining inner hides the bug
inner = over aunit id
-----
-- Some minimised code originating from optics-core follows
over
:: forall k s t a b. Is k A_Setter -- NB: setting k ~ A_Setter avoids the message
=> Optic k s t a b
-> (a -> b) -> s -> t
over o f = runFunArrow $ getOptic (castOptic' o) (FunArrow f)
where
castOptic' :: Optic k s t a b -> Optic A_Setter s t a b
castOptic' = castOptic @A_Setter
mapped :: Functor f => Optic A_Setter (f a) (f b) a b
mapped = Optic (roam fmap)
newtype Optic (k :: OpticKind) s t a b
= Optic (forall p i. Profunctor p => Optic_ k p i (Curry i) s t a b)
getOptic
:: Profunctor p
=> Optic k s t a b
-> Optic_ k p i i s t a b
getOptic (Optic o) = o
type Optic_ k p i j s t a b = Constraints k p => Optic__ p i j s t a b
type Optic__ p i j s t a b = p i a b -> p j s t
castOptic
:: forall destKind srcKind s t a b
. Is srcKind destKind
=> Optic srcKind s t a b
-> Optic destKind s t a b
castOptic (Optic o) = Optic (cast o)
where
cast
:: forall p i
. Optic_ srcKind p i i s t a b
-> Optic_ destKind p i i s t a b
cast x = implies @srcKind @destKind @p x
infixl 9 %%
(%%) :: forall s t u v a b.
Optic A_Setter s t u v
-> Optic A_Setter u v a b
-> Optic A_Setter s t a b
Optic o %% Optic o' = Optic (o . o')
class Is k l where
implies :: (Constraints k p => r) -> (Constraints l p => r)
instance Is k k where
implies r = r
type OpticKind = Type
data A_Setter :: OpticKind
-- Changing this into a synonym hides the bug
type family Constraints (k :: OpticKind) (p :: Type -> Type -> Type -> Type) :: Constraint where
Constraints A_Setter p = Mapping p
-- Changing this into a synonym hides the bug
type family Curry (y :: Type) :: Type where
Curry y = y
type IxList = [Type]
type NoIx = ('[] :: IxList)
class Profunctor p where
dimap :: (a -> b) -> (c -> d) -> p i b c -> p i a d
class Profunctor p => Strong p where
first' :: p i a b -> p i (a, c) (b, c)
class Strong p => Mapping p where
roam
:: ((a -> b) -> s -> t)
-> p i a b
-> p i s t
data Market a b i s t = Market (b -> t) (s -> Either t a)
instance Profunctor (Market a b) where
dimap f g (Market bt seta) = Market (g . bt) (either (Left . g) Right . seta . f)
-- NB: changing this to data hides the bug
newtype FunArrow i a b = FunArrow { runFunArrow :: a -> b }
instance Profunctor FunArrow where
dimap f g (FunArrow k) = FunArrow (g . k . f)
instance Strong FunArrow where
first' (FunArrow k) = FunArrow $ \ ~(a, b) -> (k a, b)
instance Mapping FunArrow where
roam f (FunArrow k) = FunArrow $ f kThis gives similar messages for ghc 9.2.2, 9.2.1, 9.0.2, 9.0.1, 8.10.7, 8.8.4
For ghc 9.2.2 with `-v`, this gives
$ ghc -v -O Bug.hs -fforce-recomp
Glasgow Haskell Compiler, Version 9.2.2, stage 2 booted by GHC version 8.10.7
*** initializing unit database:
Using binary package database: /nix/store/kmlcs0v3z7hffnkjd51ipfsl6n7x67al-ghc-9.2.2/lib/ghc-9.2.2/package.conf.d/package.cache
package flags []
loading package database /nix/store/kmlcs0v3z7hffnkjd51ipfsl6n7x67al-ghc-9.2.2/lib/ghc-9.2.2/package.conf.d
wired-in package ghc-prim mapped to ghc-prim-0.8.0
wired-in package ghc-bignum mapped to ghc-bignum-1.2
wired-in package base mapped to base-4.16.1.0
wired-in package rts mapped to rts
wired-in package template-haskell mapped to template-haskell-2.18.0.0
wired-in package ghc mapped to ghc-9.2.2
!!! initializing unit database: finished in 5.48 milliseconds, allocated 5.776 megabytes
*** initializing unit database:
package flags []
loading package database /nix/store/kmlcs0v3z7hffnkjd51ipfsl6n7x67al-ghc-9.2.2/lib/ghc-9.2.2/package.conf.d
wired-in package ghc-prim mapped to ghc-prim-0.8.0
wired-in package ghc-bignum mapped to ghc-bignum-1.2
wired-in package base mapped to base-4.16.1.0
wired-in package rts mapped to rts
wired-in package template-haskell mapped to template-haskell-2.18.0.0
wired-in package ghc mapped to ghc-9.2.2
!!! initializing unit database: finished in 14.45 milliseconds, allocated 3.381 megabytes
*** Chasing dependencies:
Chasing modules from: Bug.hs
!!! Chasing dependencies: finished in 2.93 milliseconds, allocated 2.896 megabytes
Stable obj: {}
Stable BCO: {}
Ready for upsweep
[NONREC
ModSummary {
ms_hs_date = 2022-05-11 19:21:07.193278949 UTC
ms_mod = Bug,
ms_textual_imps = [(Nothing, Prelude), (Nothing, Data.Kind),
(Nothing, Data.Coerce), (Nothing, GHC.Exts),
(Nothing, GHC.Generics)]
ms_srcimps = []
} []]
*** Deleting temp files:
Deleting:
compile: input file Bug.hs
*** Checking old interface for Bug (use -ddump-hi-diffs for more details):
[1 of 1] Compiling Bug ( Bug.hs, Bug.o )
*** Parser [Bug]:
!!! Parser [Bug]: finished in 13.91 milliseconds, allocated 4.816 megabytes
*** Renamer/typechecker [Bug]:
!!! Renamer/typechecker [Bug]: finished in 131.17 milliseconds, allocated 96.275 megabytes
*** Desugar [Bug]:
Result size of Desugar (before optimization)
= {terms: 918, types: 2,252, coercions: 434, joins: 0/76}
*** Core Linted result of Desugar (before optimization):
Result size of Desugar (after optimization)
= {terms: 633, types: 1,357, coercions: 559, joins: 0/6}
*** Core Linted result of Desugar (after optimization):
!!! Desugar [Bug]: finished in 13.59 milliseconds, allocated 15.928 megabytes
*** Simplifier [Bug]:
Result size of Simplifier iteration=1
= {terms: 710, types: 1,204, coercions: 996, joins: 0/23}
*** Core Linted result of Simplifier:
exprIsLambda_maybe: Unexpected lambda in case
\ (eta_B0 :: B) ->
B ((inner_s2Sp
`cast` ((N:FunArrow[0]
<Type>_N Univ(phantom phantom <Type>_N :: Curry Any, Any)
; Sym (N:FunArrow[0] <Type>_N <Any>_P)) <A>_N <A>_N
; N:FunArrow[0] <Type>_N <Any>_P <A>_N <A>_N
:: FunArrow (Curry Any) A A ~R# (A -> A)))
(case case eta_B0 of { B e_a14H -> (e_a14H, B e_a14H) } of
{ (a_a142, _ [Occ=Dead]) ->
a_a142
}))
Result size of Simplifier iteration=2
= {terms: 649, types: 858, coercions: 705, joins: 0/11}
*** Core Linted result of Simplifier:
Result size of Simplifier
= {terms: 531, types: 497, coercions: 352, joins: 0/1}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 25.10 milliseconds, allocated 34.110 megabytes
*** Specialise [Bug]:
Result size of Specialise
= {terms: 531, types: 497, coercions: 352, joins: 0/1}
*** Core Linted result of Specialise:
!!! Specialise [Bug]: finished in 1.88 milliseconds, allocated 3.084 megabytes
*** Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = False}) [Bug]:
Result size of Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = False})
= {terms: 537, types: 508, coercions: 352, joins: 0/2}
*** Core Linted result of Float out(FOS {Lam = Just 0, Consts = True, OverSatApps = False}):
!!! Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = False}) [Bug]: finished in 2.57 milliseconds, allocated 3.978 megabytes
*** Simplifier [Bug]:
Result size of Simplifier iteration=1
= {terms: 535, types: 502, coercions: 352, joins: 0/2}
*** Core Linted result of Simplifier:
Result size of Simplifier
= {terms: 535, types: 502, coercions: 352, joins: 0/2}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 6.53 milliseconds, allocated 9.401 megabytes
*** Simplifier [Bug]:
Result size of Simplifier iteration=1
= {terms: 531, types: 498, coercions: 352, joins: 0/2}
*** Core Linted result of Simplifier:
Result size of Simplifier
= {terms: 529, types: 495, coercions: 352, joins: 0/2}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 6.38 milliseconds, allocated 9.361 megabytes
*** Simplifier [Bug]:
Result size of Simplifier
= {terms: 529, types: 495, coercions: 352, joins: 0/2}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 2.91 milliseconds, allocated 4.675 megabytes
*** Float inwards [Bug]:
Result size of Float inwards
= {terms: 529, types: 495, coercions: 352, joins: 0/2}
*** Core Linted result of Float inwards:
!!! Float inwards [Bug]: finished in 1.71 milliseconds, allocated 2.924 megabytes
*** Called arity analysis [Bug]:
Result size of Called arity analysis
= {terms: 529, types: 495, coercions: 352, joins: 0/2}
*** Core Linted result of Called arity analysis:
!!! Called arity analysis [Bug]: finished in 1.89 milliseconds, allocated 3.126 megabytes
*** Simplifier [Bug]:
Result size of Simplifier iteration=1
= {terms: 529, types: 495, coercions: 352, joins: 0/2}
*** Core Linted result of Simplifier:
Result size of Simplifier
= {terms: 505, types: 487, coercions: 352, joins: 0/2}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 6.56 milliseconds, allocated 9.260 megabytes
*** Demand analysis [Bug]:
Result size of Demand analysis
= {terms: 505, types: 487, coercions: 352, joins: 0/2}
*** Core Linted result of Demand analysis:
!!! Demand analysis [Bug]: finished in 1.86 milliseconds, allocated 3.053 megabytes
*** Constructed Product Result analysis [Bug]:
Result size of Constructed Product Result analysis
= {terms: 505, types: 487, coercions: 352, joins: 0/2}
*** Core Linted result of Constructed Product Result analysis:
!!! Constructed Product Result analysis [Bug]: finished in 1.79 milliseconds, allocated 2.812 megabytes
*** Worker Wrapper binds [Bug]:
Result size of Worker Wrapper binds
= {terms: 579, types: 737, coercions: 352, joins: 0/10}
*** Core Linted result of Worker Wrapper binds:
!!! Worker Wrapper binds [Bug]: finished in 2.68 milliseconds, allocated 3.937 megabytes
*** Simplifier [Bug]:
Result size of Simplifier iteration=1
= {terms: 556, types: 650, coercions: 352, joins: 0/6}
*** Core Linted result of Simplifier:
Result size of Simplifier iteration=2
= {terms: 511, types: 539, coercions: 352, joins: 0/1}
*** Core Linted result of Simplifier:
Result size of Simplifier
= {terms: 511, types: 539, coercions: 352, joins: 0/1}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 11.98 milliseconds, allocated 16.524 megabytes
*** Exitification transformation [Bug]:
Result size of Exitification transformation
= {terms: 511, types: 539, coercions: 352, joins: 0/1}
*** Core Linted result of Exitification transformation:
!!! Exitification transformation [Bug]: finished in 1.89 milliseconds, allocated 3.182 megabytes
*** Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = True}) [Bug]:
Result size of Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = True})
= {terms: 511, types: 539, coercions: 352, joins: 0/1}
*** Core Linted result of Float out(FOS {Lam = Just 0, Consts = True, OverSatApps = True}):
!!! Float out(FOS {Lam = Just 0,
Consts = True,
OverSatApps = True}) [Bug]: finished in 2.79 milliseconds, allocated 4.431 megabytes
*** Common sub-expression [Bug]:
Result size of Common sub-expression
= {terms: 509, types: 539, coercions: 352, joins: 0/1}
*** Core Linted result of Common sub-expression:
!!! Common sub-expression [Bug]: finished in 2.41 milliseconds, allocated 3.707 megabytes
*** Float inwards [Bug]:
Result size of Float inwards
= {terms: 509, types: 539, coercions: 352, joins: 0/1}
*** Core Linted result of Float inwards:
!!! Float inwards [Bug]: finished in 2.06 milliseconds, allocated 3.367 megabytes
*** Simplifier [Bug]:
Result size of Simplifier
= {terms: 505, types: 537, coercions: 352, joins: 0/1}
*** Core Linted result of Simplifier:
!!! Simplifier [Bug]: finished in 4.38 milliseconds, allocated 5.316 megabytes
*** Demand analysis [Bug]:
Result size of Demand analysis
= {terms: 505, types: 537, coercions: 352, joins: 0/1}
*** Core Linted result of Demand analysis:
!!! Demand analysis [Bug]: finished in 2.79 milliseconds, allocated 3.559 megabytes
*** CoreTidy [Bug]:
Result size of Tidy Core
= {terms: 547, types: 802, coercions: 358, joins: 0/1}
*** Core Linted result of Tidy Core:
!!! CoreTidy [Bug]: finished in 3.54 milliseconds, allocated 4.984 megabytes
Created temporary directory: /tmp/nix-shell.EmVGaD/ghc3059898_0
*** CorePrep [Bug]:
Result size of CorePrep
= {terms: 648, types: 1,073, coercions: 358, joins: 0/12}
*** Core Linted result of CorePrep:
!!! CorePrep [Bug]: finished in 4.41 milliseconds, allocated 4.674 megabytes
*** CoreToStg [Bug]:
*** Stg2Stg:
!!! CoreToStg [Bug]: finished in 0.40 milliseconds, allocated 0.848 megabytes
*** CodeGen [Bug]:
!!! CodeGen [Bug]: finished in 16.99 milliseconds, allocated 20.930 megabytes
*** systool:as:
*** Assembler:
/nix/store/bg35nfwn6zd616facdywiysgpprfvsji-gcc-wrapper-11.3.0/bin/cc -iquote. -no-pie -fno-PIC -x assembler -c /tmp/nix-shell.EmVGaD/ghc3059898_0/ghc_2.s -o Bug.o.tmp
!!! systool:as: finished in 0.36 milliseconds, allocated 0.122 megabytes
Upsweep completely successful.
*** Deleting temp files:
Deleting: /tmp/nix-shell.EmVGaD/ghc3059898_0/ghc_1.s /tmp/nix-shell.EmVGaD/ghc3059898_0/ghc_2.s /tmp/nix-shell.EmVGaD/ghc3059898_0/ghc_3.c
Warning: deleting non-existent /tmp/nix-shell.EmVGaD/ghc3059898_0/ghc_1.s
Warning: deleting non-existent /tmp/nix-shell.EmVGaD/ghc3059898_0/ghc_3.c
link(batch): upsweep (partially) failed OR
Main.main not exported; not linking.
*** Deleting temp files:
Deleting:
*** Deleting temp dirs:
Deleting: /tmp/nix-shell.EmVGaD/ghc3059898_0
Expected behavior
Successfully and quietly compile, like any other module would.
Environment
- GHC version used: 9.2.2, 9.2.1, 9.0.2, 9.0.1, 8.10.7, 8.8.4 from nixpkgs-21.11 and nixpkgs-unstable
A nix flake for reproducability:
(run nix run .#run-922 etc in a directory with the standalone Bug.hs). (For use with the one depending on optics-core, add p.optics-core to the ghcWithPackages list, but this only works on nixos-unstable due to needing optics-core 0.4)
For nixpkgs-unstable:
{
description = "A very basic flake";
inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
outputs = { self, nixpkgs }:
let pkgs = import nixpkgs { system = "x86_64-linux"; };
defaultGhcVersion = "ghc922";
haskellPkgs = ghcVersion: pkgs.haskell.packages.${ghcVersion};
deps = ghcVersion: [ ((haskellPkgs ghcVersion).ghcWithPackages (p: [ ]))];
testScript = ghcVersion: pkgs.writeShellApplication {
name = "test-${ghcVersion}";
runtimeInputs = deps ghcVersion;
text = "ghc -O Bug.hs -fforce-recomp"; };
in {
devShell.x86_64-linux = pkgs.mkShell { packages = deps defaultGhcVersion ;};
apps.x86_64-linux.run-default = testScript defaultGhcVersion;
apps.x86_64-linux.run-884 = testScript "ghc884";
apps.x86_64-linux.run-8107 = testScript "ghc8107";
apps.x86_64-linux.run-902 = testScript "ghc902";
apps.x86_64-linux.run-922 = testScript "ghc922";
};
}{
"nodes": {
"nixpkgs": {
"locked": {
"lastModified": 1652172129,
"narHash": "sha256-8e2JMrswaKe02P8rYfvIMoc59pNuw6h/GYu8DBE1c+0=",
"owner": "NixOS",
"repo": "nixpkgs",
"rev": "f419dc5763c2b3c5580e396dea065b6d8b58ee27",
"type": "github"
},
"original": {
"owner": "NixOS",
"ref": "nixos-unstable",
"repo": "nixpkgs",
"type": "github"
}
},
"root": {
"inputs": {
"nixpkgs": "nixpkgs"
}
}
},
"root": "root",
"version": 7
}For nixos-21.11
{
description = "A very basic flake";
inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-21.11";
outputs = { self, nixpkgs }:
let pkgs = import nixpkgs { system = "x86_64-linux"; };
defaultGhcVersion = "ghc921";
haskellPkgs = ghcVersion: pkgs.haskell.packages.${ghcVersion};
deps = ghcVersion: [ ((haskellPkgs ghcVersion).ghcWithPackages (p: [ ]))];
testScript = ghcVersion: pkgs.writeShellApplication {
name = "test-${ghcVersion}";
runtimeInputs = deps ghcVersion;
text = "ghc -O App.hs -fforce-recomp"; };
in {
devShell.x86_64-linux = pkgs.mkShell { packages = deps defaultGhcVersion ;};
apps.x86_64-linux.run-default = testScript defaultGhcVersion;
apps.x86_64-linux.run-884 = testScript "ghc884";
apps.x86_64-linux.run-8107 = testScript "ghc8107";
apps.x86_64-linux.run-901 = testScript "ghc901";
apps.x86_64-linux.run-921 = testScript "ghc921";
};
}{
"nodes": {
"nixpkgs": {
"locked": {
"lastModified": 1651310835,
"narHash": "sha256-MLk/zsLlbPhwFucxL64Fr+oIrvQC2/76Ap2F7ekbPNI=",
"owner": "NixOS",
"repo": "nixpkgs",
"rev": "fd3e33d696b81e76b30160dfad2efb7ac1f19879",
"type": "github"
},
"original": {
"owner": "NixOS",
"ref": "nixos-21.11",
"repo": "nixpkgs",
"type": "github"
}
},
"root": {
"inputs": {
"nixpkgs": "nixpkgs"
}
}
},
"root": "root",
"version": 7
}Optional:
- Operating System: NixOS
- System Architecture: x86_64
However, a similar symptom has been noticed on an Apple Silicon mac in CI
Edited by Ben Price