#15388: GHC reports missing INLINABLE pragmas in vector and ghc-prim -------------------------------------+------------------------------------- Reporter: ChaiTRex | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.4.3 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- When compiling a program with GHC 8.4.3, vector 0.12.0.1 (with a dependency on primitive 0.6.4.0) and `-Weverything`, I get several warnings that `INLINABLE` pragmas should be added to the vector and ghc- prim packages. It would be nicer if these warnings didn't happen, even with `-Weverything`. Also, perhaps there are optimization opportunities that are lost. A somewhat reduced example (can be reduced further by removing the function definitions and unused imports that creates): {{{#!hs lineno=1 {-# OPTIONS_GHC -Wall-missed-specialisations #-} {-# LANGUAGE MultiParamTypeClasses, TypeFamilies #-} module Warnings2 where import GHC.Base (liftM) import qualified Data.Vector.Generic.Base as G (Vector, basicUnsafeFreeze, basicUnsafeThaw, basicLength, basicUnsafeSlice, basicUnsafeIndexM, basicUnsafeCopy, elemseq) import qualified Data.Vector.Generic.Mutable.Base as GM (MVector, basicLength, basicUnsafeSlice, basicOverlaps, basicUnsafeNew, basicInitialize, basicUnsafeReplicate, basicUnsafeRead, basicUnsafeWrite, basicClear, basicSet, basicUnsafeCopy, basicUnsafeMove, basicUnsafeGrow) import qualified Data.Vector.Unboxed as U (Unbox, Vector) import qualified Data.Vector.Unboxed.Mutable as U (MVector) newtype T = T () deriving (Show, Eq, Ord) newtype C = C (T, U.Vector T) deriving (Show, Eq, Ord) instance U.Unbox T newtype instance U.MVector s T = MV_T (U.MVector s ()) instance GM.MVector U.MVector T where basicLength (MV_T mv) = GM.basicLength mv basicUnsafeSlice i l (MV_T mv) = MV_T (GM.basicUnsafeSlice i l mv) basicOverlaps (MV_T mv1) (MV_T mv2) = GM.basicOverlaps mv1 mv2 basicUnsafeNew l = MV_T `liftM` GM.basicUnsafeNew l basicInitialize (MV_T mv) = GM.basicInitialize mv basicUnsafeReplicate l _ = MV_T `liftM` GM.basicUnsafeReplicate l () basicUnsafeRead (MV_T mv) i = const (T ()) `liftM` GM.basicUnsafeRead mv i basicUnsafeWrite (MV_T mv) i _ = GM.basicUnsafeWrite mv i () basicClear (MV_T mv) = GM.basicClear mv basicSet (MV_T mv) x = GM.basicSet mv () basicUnsafeCopy (MV_T mv1) (MV_T mv2) = GM.basicUnsafeCopy mv1 mv2 basicUnsafeMove (MV_T mv1) (MV_T mv2) = GM.basicUnsafeMove mv1 mv2 basicUnsafeGrow (MV_T mv) l = MV_T `liftM` GM.basicUnsafeGrow mv l newtype instance U.Vector T = V_T (U.Vector ()) instance G.Vector U.Vector T where basicUnsafeFreeze (MV_T mv) = V_T `liftM` G.basicUnsafeFreeze mv basicUnsafeThaw (V_T v) = MV_T `liftM` G.basicUnsafeThaw v basicLength (V_T v) = G.basicLength v basicUnsafeSlice i l (V_T v) = V_T (G.basicUnsafeSlice i l v) basicUnsafeIndexM (V_T v) i = const (T ()) `liftM` G.basicUnsafeIndexM v i basicUnsafeCopy (MV_T mv) (V_T v) = G.basicUnsafeCopy mv v elemseq (V_T v) _ = G.elemseq v () }}} The warnings: {{{#!default lineno=1 marks=16,31,46 src/Warnings2.hs: warning: Could not specialise imported function ‘Data.Vector.Unboxed.$w$cshowsPrec’ when specialising ‘Data.Vector.Unboxed.$fShowVector_$cshowsPrec’ when specialising ‘Data.Vector.Unboxed.$fShowVector’ Probable fix: add INLINABLE pragma on ‘Data.Vector.Unboxed.$w$cshowsPrec’ src/Warnings2.hs: warning: Could not specialise imported function ‘Data.Vector.Unboxed.$fShowVector_$cshow’ when specialising ‘Data.Vector.Unboxed.$fShowVector’ Probable fix: add INLINABLE pragma on ‘Data.Vector.Unboxed.$fShowVector_$cshow’ src/Warnings2.hs: warning: Could not specialise imported function ‘Data.Vector.Unboxed.$fShowVector_$cshowList’ when specialising ‘Data.Vector.Unboxed.$fShowVector’ Probable fix: add INLINABLE pragma on ‘Data.Vector.Unboxed.$fShowVector_$cshowList’ src/Warnings2.hs: warning: Could not specialise imported function ‘ghc- prim-0.5.2.0:GHC.Classes.$w$c==’ when specialising ‘ghc-prim-0.5.2.0:GHC.Classes.$fEq(,)_$c==’ Probable fix: add INLINABLE pragma on ‘ghc- prim-0.5.2.0:GHC.Classes.$w$c==’ src/Warnings2.hs: warning: Could not specialise imported function ‘Data.Vector.Unboxed.$fOrdVector_$cmax’ when specialising ‘Data.Vector.Unboxed.$fOrdVector’ Probable fix: add INLINABLE pragma on ‘Data.Vector.Unboxed.$fOrdVector_$cmax’ src/Warnings2.hs: warning: Could not specialise imported function ‘Data.Vector.Unboxed.$fOrdVector_$cmin’ when specialising ‘Data.Vector.Unboxed.$fOrdVector’ Probable fix: add INLINABLE pragma on ‘Data.Vector.Unboxed.$fOrdVector_$cmin’ src/Warnings2.hs: warning: Could not specialise imported function ‘ghc- prim-0.5.2.0:GHC.Classes.$w$c>=’ when specialising ‘ghc-prim-0.5.2.0:GHC.Classes.$fOrd(,)_$c>=’ Probable fix: add INLINABLE pragma on ‘ghc- prim-0.5.2.0:GHC.Classes.$w$c>=’ src/Warnings2.hs: warning: Could not specialise imported function ‘ghc- prim-0.5.2.0:GHC.Classes.$w$c<’ when specialising ‘ghc-prim-0.5.2.0:GHC.Classes.$fOrd(,)_$c<’ Probable fix: add INLINABLE pragma on ‘ghc- prim-0.5.2.0:GHC.Classes.$w$c<’ src/Warnings2.hs: warning: Could not specialise imported function ‘ghc- prim-0.5.2.0:GHC.Classes.$w$c<=’ when specialising ‘ghc-prim-0.5.2.0:GHC.Classes.$fOrd(,)_$c<=’ Probable fix: add INLINABLE pragma on ‘ghc- prim-0.5.2.0:GHC.Classes.$w$c<=’ src/Warnings2.hs: warning: Could not specialise imported function ‘ghc- prim-0.5.2.0:GHC.Classes.$w$ccompare’ when specialising ‘ghc-prim-0.5.2.0:GHC.Classes.$fOrd(,)_$ccompare’ Probable fix: add INLINABLE pragma on ‘ghc- prim-0.5.2.0:GHC.Classes.$w$ccompare’ }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15388 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler