4 files changed, 2 insertions, 32 deletions
diff --git a/libraries/base/GHC/Read.hs b/libraries/base/GHC/Read.hs
index 43e5ee5b32..7f698ec498 100644
--- a/libraries/base/GHC/Read.hs
+++ b/libraries/base/GHC/Read.hs
@@ -669,25 +669,7 @@ instance Read () where
   readList     = readListDefault
 
 -- | @since 4.15
-instance Read a => Read (Solo a) where
-  -- Since our `show` doesn't show record syntax, we want to accept non-record
-  -- syntax. Since Solo is actually a record, it only seems fair to accept
-  -- record syntax as well.
-  readPrec = parens $
-     (prec appPrec $
-        do expectP (L.Ident "Solo")
-           x <- step readPrec
-           return (Solo x))
-     +++
-      (prec appPrec1
-             (do expectP (L.Ident "Solo")
-                 expectP (L.Punc "{")
-                 x <- readField
-                              "getSolo" (reset readPrec)
-                 expectP (L.Punc "}")
-                 return (Solo x)))
-
-  readListPrec = readListPrecDefault
+deriving instance Read a => Read (Solo a)
 
 -- | @since 2.01
 instance (Read a, Read b) => Read (a,b) where
diff --git a/libraries/base/GHC/Show.hs b/libraries/base/GHC/Show.hs
index ecfb7dbe0f..04fbcb6112 100644
--- a/libraries/base/GHC/Show.hs
+++ b/libraries/base/GHC/Show.hs
@@ -169,9 +169,7 @@ appPrec1 = I# 11#       -- appPrec + 1
 deriving instance Show ()
 
 -- | @since 4.15
-instance Show a => Show (Solo a) where
-  showsPrec d (Solo x) = showParen (d > 10) $
-      showString "Solo " . showsPrec 11 x
+deriving instance Show a => Show (Solo a)
 
 -- | @since 2.01
 instance Show a => Show [a]  where
diff --git a/libraries/base/tests/all.T b/libraries/base/tests/all.T
index 371ed56327..ebbf81ec52 100644
--- a/libraries/base/tests/all.T
+++ b/libraries/base/tests/all.T
@@ -45,7 +45,6 @@ test('inits', normal, compile_and_run, [''])
 test('genericNegative001', extra_run_opts('-1'), compile_and_run, [''])
 test('ix001', normal, compile_and_run, [''])
 test('isValidNatural', normal, compile_and_run, [''])
-test('read-show-solo', normal, compile_and_run, [''])
 
 # need to add -K64m to the compiler opts, so that GHCi gets it too
 test('ioref001',
diff --git a/libraries/base/tests/read-show-solo.hs b/libraries/base/tests/read-show-solo.hs
deleted file mode 100644
index 553e837836..0000000000
--- a/libraries/base/tests/read-show-solo.hs
+++ /dev/null
@@ -1,9 +0,0 @@
-module Main (main) where
-import Data.Tuple (Solo (..))
-
-main = do
-  print $ Solo (3 :: Int)
-  print $ Solo (Just "")
-  print $ Just (Solo "")
-  print (read (show (Solo (3 :: Int))) :: Solo Int)
-  print (read "Just Solo { getSolo = 5 }" :: Maybe (Solo Int))