compiler: introduce custom "GhcPrelude" Prelude

This switches the compiler/ component to get compiled with
-XNoImplicitPrelude and a `import GhcPrelude` is inserted in all
modules.

This is motivated by the upcoming "Prelude" re-export of
`Semigroup((<>))` which would cause lots of name clashes in every
modulewhich imports also `Outputable`

Reviewers: austin, goldfire, bgamari, alanz, simonmar

Reviewed By: bgamari

Subscribers: goldfire, rwbarton, thomie, mpickering, bgamari

Differential Revision: https://phabricator.haskell.org/D3989

1 files changed, 2 insertions, 0 deletions

diff --git a/compiler/utils/UniqSet.hs b/compiler/utils/UniqSet.hs
index d09b337d12..be600a09b3 100644
--- a/compiler/utils/UniqSet.hs
+++ b/compiler/utils/UniqSet.hs
@@ -46,6 +46,8 @@ module UniqSet (
         nonDetFoldUniqSet_Directly
     ) where
 
+import GhcPrelude
+
 import UniqFM
 import Unique
 import Data.Coerce