Use explicit language extensions & remove extension fields from base.cabal

Add explicit {-# LANGUAGE xxx #-} pragmas to each module, that say
what extensions that module uses.  This makes it clearer where
different extensions are used in the (large, variagated) base package.

Now base.cabal doesn't need any extensions field

Thanks to Bas van Dijk for doing all the work.

15 files changed, 45 insertions, 15 deletions

diff --git a/libraries/base/Foreign/C.hs b/libraries/base/Foreign/C.hs
index cb8dfef3b5..2c7fd2e24f 100644
--- a/libraries/base/Foreign/C.hs
+++ b/libraries/base/Foreign/C.hs
@@ -1,4 +1,5 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.C
diff --git a/libraries/base/Foreign/C/Error.hs b/libraries/base/Foreign/C/Error.hs
index 8d149c1dc6..89c736d065 100644
--- a/libraries/base/Foreign/C/Error.hs
+++ b/libraries/base/Foreign/C/Error.hs
@@ -1,4 +1,6 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude -#include "HsBase.h" #-}
+{-# LANGUAGE CPP, NoImplicitPrelude, ForeignFunctionInterface #-}
+{-# OPTIONS_GHC -#include "HsBase.h" #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.C.Error
diff --git a/libraries/base/Foreign/C/String.hs b/libraries/base/Foreign/C/String.hs
index 680c81a167..becfa4ea68 100644
--- a/libraries/base/Foreign/C/String.hs
+++ b/libraries/base/Foreign/C/String.hs
@@ -1,4 +1,5 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.C.String
diff --git a/libraries/base/Foreign/C/Types.hs b/libraries/base/Foreign/C/Types.hs
index e30a2baf21..22bae5c187 100644
--- a/libraries/base/Foreign/C/Types.hs
+++ b/libraries/base/Foreign/C/Types.hs
@@ -1,7 +1,12 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP
+           , NoImplicitPrelude
+           , MagicHash
+           , GeneralizedNewtypeDeriving
+  #-}
 {-# OPTIONS_GHC -fno-warn-unused-binds #-}
 -- XXX -fno-warn-unused-binds stops us warning about unused constructors,
 -- but really we should just remove them if we don't want them
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.C.Types
diff --git a/libraries/base/Foreign/Concurrent.hs b/libraries/base/Foreign/Concurrent.hs
index a914d9532f..e0f2faaa95 100644
--- a/libraries/base/Foreign/Concurrent.hs
+++ b/libraries/base/Foreign/Concurrent.hs
@@ -1,4 +1,5 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.Concurrent
diff --git a/libraries/base/Foreign/ForeignPtr.hs b/libraries/base/Foreign/ForeignPtr.hs
index a824914ee0..b91ffebf52 100644
--- a/libraries/base/Foreign/ForeignPtr.hs
+++ b/libraries/base/Foreign/ForeignPtr.hs
@@ -1,4 +1,5 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.ForeignPtr
diff --git a/libraries/base/Foreign/Marshal.hs b/libraries/base/Foreign/Marshal.hs
index 2c16c018fe..77a4ebf3cc 100644
--- a/libraries/base/Foreign/Marshal.hs
+++ b/libraries/base/Foreign/Marshal.hs
@@ -1,4 +1,5 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.Marshal
diff --git a/libraries/base/Foreign/Marshal/Alloc.hs b/libraries/base/Foreign/Marshal/Alloc.hs
index 5c86155d58..ddb4a90bae 100644
--- a/libraries/base/Foreign/Marshal/Alloc.hs
+++ b/libraries/base/Foreign/Marshal/Alloc.hs
@@ -1,4 +1,10 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP
+           , NoImplicitPrelude
+           , MagicHash
+           , UnboxedTuples
+           , ForeignFunctionInterface
+  #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.Marshal.Alloc
diff --git a/libraries/base/Foreign/Marshal/Array.hs b/libraries/base/Foreign/Marshal/Array.hs
index 9e8d08287d..1ca3e9e236 100644
--- a/libraries/base/Foreign/Marshal/Array.hs
+++ b/libraries/base/Foreign/Marshal/Array.hs
@@ -1,4 +1,5 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude, MagicHash #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.Marshal.Array
diff --git a/libraries/base/Foreign/Marshal/Error.hs b/libraries/base/Foreign/Marshal/Error.hs
index b018f2ab0c..ccf514d70d 100644
--- a/libraries/base/Foreign/Marshal/Error.hs
+++ b/libraries/base/Foreign/Marshal/Error.hs
@@ -1,4 +1,5 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.Marshal.Error
diff --git a/libraries/base/Foreign/Marshal/Pool.hs b/libraries/base/Foreign/Marshal/Pool.hs
index f15d048a95..ed94e464fb 100644
--- a/libraries/base/Foreign/Marshal/Pool.hs
+++ b/libraries/base/Foreign/Marshal/Pool.hs
@@ -1,4 +1,5 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude #-}
+
 --------------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.Marshal.Pool
diff --git a/libraries/base/Foreign/Marshal/Utils.hs b/libraries/base/Foreign/Marshal/Utils.hs
index 7fcacfa8c7..5ae677a19d 100644
--- a/libraries/base/Foreign/Marshal/Utils.hs
+++ b/libraries/base/Foreign/Marshal/Utils.hs
@@ -1,4 +1,5 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude, ForeignFunctionInterface #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.Marshal.Utils
diff --git a/libraries/base/Foreign/Ptr.hs b/libraries/base/Foreign/Ptr.hs
index 8dd220f769..b46acc1bea 100644
--- a/libraries/base/Foreign/Ptr.hs
+++ b/libraries/base/Foreign/Ptr.hs
@@ -1,4 +1,10 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP
+           , NoImplicitPrelude
+           , ForeignFunctionInterface
+           , MagicHash
+           , GeneralizedNewtypeDeriving
+  #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.Ptr
diff --git a/libraries/base/Foreign/StablePtr.hs b/libraries/base/Foreign/StablePtr.hs
index cfcd239134..522c6fc344 100644
--- a/libraries/base/Foreign/StablePtr.hs
+++ b/libraries/base/Foreign/StablePtr.hs
@@ -1,4 +1,5 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.StablePtr
diff --git a/libraries/base/Foreign/Storable.hs b/libraries/base/Foreign/Storable.hs
index 0b0ad0cda1..700a4ff5ee 100644
--- a/libraries/base/Foreign/Storable.hs
+++ b/libraries/base/Foreign/Storable.hs
@@ -1,4 +1,5 @@
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude, ScopedTypeVariables #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Foreign.Storable