Merge branch 'master' into wip/binary-readerTwip/binary-readerT

2 files changed, 13 insertions, 12 deletions

diff --git a/libraries/ghci/GHCi/CreateBCO.hs b/libraries/ghci/GHCi/CreateBCO.hs
index 96fc4418ff..7098c27fb8 100644
--- a/libraries/ghci/GHCi/CreateBCO.hs
+++ b/libraries/ghci/GHCi/CreateBCO.hs
@@ -23,6 +23,7 @@ import System.IO (fixIO)
 import Control.Monad
 import Data.Array.Base
 import Foreign hiding (newArray)
+import Unsafe.Coerce (unsafeCoerce)
 import GHC.Arr          ( Array(..) )
 import GHC.Exts
 import GHC.IO
@@ -44,7 +45,9 @@ createBCO _   ResolvedBCO{..} | resolvedBCOIsLE /= isLittleEndian
                 , "mixed endianness setup is not supported!"
                 ])
 createBCO arr bco
-   = do BCO bco# <- linkBCO' arr bco
+   = do linked_bco <- linkBCO' arr bco
+        -- Note [Updatable CAF BCOs]
+        -- ~~~~~~~~~~~~~~~~~~~~~~~~~
         -- Why do we need mkApUpd0 here?  Otherwise top-level
         -- interpreted CAFs don't get updated after evaluation.  A
         -- top-level BCO will evaluate itself and return its value
@@ -57,9 +60,10 @@ createBCO arr bco
         --   (c) An AP is always fully saturated, so we *can't* wrap
         --       non-zero arity BCOs in an AP thunk.
         --
+        -- See #17424.
         if (resolvedBCOArity bco > 0)
-           then return (HValue (unsafeCoerce# bco#))
-           else case mkApUpd0# bco# of { (# final_bco #) ->
+           then return (HValue (unsafeCoerce linked_bco))
+           else case mkApUpd0# linked_bco of { (# final_bco #) ->
                   return (HValue final_bco) }
 
 
@@ -102,8 +106,8 @@ mkPtrsArray arr n_ptrs ptrs = do
     fill (ResolvedBCOStaticPtr r) i = do
       writePtrsArrayPtr i (fromRemotePtr r)  marr
     fill (ResolvedBCOPtrBCO bco) i = do
-      BCO bco# <- linkBCO' arr bco
-      writePtrsArrayBCO i bco# marr
+      bco <- linkBCO' arr bco
+      writePtrsArrayBCO i bco marr
     fill (ResolvedBCOPtrBreakArray r) i = do
       BA mba <- localRef r
       writePtrsArrayMBA i mba marr
@@ -130,23 +134,20 @@ writePtrsArrayPtr (I# i) (Ptr a#) (PtrsArr arr) = IO $ \s ->
 writeArrayAddr# :: MutableArray# s a -> Int# -> Addr# -> State# s -> State# s
 writeArrayAddr# marr i addr s = unsafeCoerce# writeArray# marr i addr s
 
-writePtrsArrayBCO :: Int -> BCO# -> PtrsArr -> IO ()
+writePtrsArrayBCO :: Int -> BCO -> PtrsArr -> IO ()
 writePtrsArrayBCO (I# i) bco (PtrsArr arr) = IO $ \s ->
   case (unsafeCoerce# writeArray#) arr i bco s of s' -> (# s', () #)
 
-data BCO = BCO BCO#
-
 writePtrsArrayMBA :: Int -> MutableByteArray# s -> PtrsArr -> IO ()
 writePtrsArrayMBA (I# i) mba (PtrsArr arr) = IO $ \s ->
   case (unsafeCoerce# writeArray#) arr i mba s of s' -> (# s', () #)
 
 newBCO :: ByteArray# -> ByteArray# -> Array# a -> Int# -> ByteArray# -> IO BCO
 newBCO instrs lits ptrs arity bitmap = IO $ \s ->
-  case newBCO# instrs lits ptrs arity bitmap s of
-    (# s1, bco #) -> (# s1, BCO bco #)
+  newBCO# instrs lits ptrs arity bitmap s
 
 {- Note [BCO empty array]
-
+   ~~~~~~~~~~~~~~~~~~~~~~
 Lots of BCOs have empty ptrs or nptrs, but empty arrays are not free:
 they are 2-word heap objects.  So let's make a single empty array and
 share it between all BCOs.
diff --git a/libraries/ghci/GHCi/RemoteTypes.hs b/libraries/ghci/GHCi/RemoteTypes.hs
index c024ae9fff..6a552f37da 100644
--- a/libraries/ghci/GHCi/RemoteTypes.hs
+++ b/libraries/ghci/GHCi/RemoteTypes.hs
@@ -33,7 +33,7 @@ import GHC.ForeignPtr
 -- Static pointers only; don't use this for heap-resident pointers.
 -- Instead use HValueRef. We will fix the remote pointer to be 64 bits. This
 -- should cover 64 and 32bit systems, and permits the exchange of remote ptrs
--- between machines of different word size. For exmaple, when connecting to
+-- between machines of different word size. For example, when connecting to
 -- an iserv instance on a different architecture with different word size via
 -- -fexternal-interpreter.
 newtype RemotePtr a = RemotePtr Word64