diff options
| author | Sylvain Henry <sylvain@haskus.fr> | 2021-03-12 14:09:37 +0100 |
|---|---|---|
| committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2021-03-17 19:08:27 -0400 |
| commit | 6b10163e0da90dfc0eeb52549598faa2c0527e37 (patch) | |
| tree | bd4e165881b813db87c23dbca71ca45b41093b71 | |
| parent | fe6cad22353ee027358251cbf91a3811c6e925ff (diff) | |
| download | haskell-6b10163e0da90dfc0eeb52549598faa2c0527e37.tar.gz | |
Disable bogus assertion (#19489)
| -rw-r--r-- | compiler/GHC/CoreToStg/Prep.hs | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/compiler/GHC/CoreToStg/Prep.hs b/compiler/GHC/CoreToStg/Prep.hs index 3eb714405c..5395a737d6 100644 --- a/compiler/GHC/CoreToStg/Prep.hs +++ b/compiler/GHC/CoreToStg/Prep.hs @@ -1407,8 +1407,21 @@ mkFloat dmd is_unlifted bndr rhs -- Don't make a case for a HNF binding, even if it's strict -- Otherwise we get case (\x -> e) of ...! - | is_unlifted = ASSERT2( ok_for_spec, ppr rhs ) - FloatCase rhs bndr DEFAULT [] True + | is_unlifted = FloatCase rhs bndr DEFAULT [] True + -- we used to ASSERT2(ok_for_spec, ppr rhs) here, but it is now disabled + -- because exprOkForSpeculation isn't stable under ANF-ing. See for + -- example #19489 where the following unlifted expression: + -- + -- GHC.Prim.(#|_#) @LiftedRep @LiftedRep @[a_ax0] @[a_ax0] + -- (GHC.Types.: @a_ax0 a2_agq a3_agl) + -- + -- is ok-for-spec but is ANF-ised into: + -- + -- let sat = GHC.Types.: @a_ax0 a2_agq a3_agl + -- in GHC.Prim.(#|_#) @LiftedRep @LiftedRep @[a_ax0] @[a_ax0] sat + -- + -- which isn't ok-for-spec because of the let-expression. + | is_hnf = FloatLet (NonRec bndr rhs) | otherwise = FloatLet (NonRec (setIdDemandInfo bndr dmd) rhs) -- See Note [Pin demand info on floats] |