PostTcType replaced with TypeAnnot

Summary:
This is a first step toward allowing generic traversals of the AST without 'landmines', by removing the `panic`s located throughout `placeHolderType`, `placeHolderKind` & co.

See more on the discussion at https://www.mail-archive.com/ghc-devs@haskell.org/msg05564.html

(This also makes a corresponding update to the `haddock` submodule.)

Test Plan: `sh validate` and new tests pass.

Reviewers: austin, simonpj, goldfire

Reviewed By: austin, simonpj, goldfire

Subscribers: edsko, Fuuzetsu, thomasw, holzensp, goldfire, simonmar, relrod, ezyang, carter

Projects: #ghc

Differential Revision: https://phabricator.haskell.org/D157

1 files changed, 26 insertions, 0 deletions

diff --git a/testsuite/tests/ghc-api/landmines/MineKind.hs b/testsuite/tests/ghc-api/landmines/MineKind.hs
new file mode 100644
index 0000000000..c97a996c66
--- /dev/null
+++ b/testsuite/tests/ghc-api/landmines/MineKind.hs
@@ -0,0 +1,26 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE GADTs #-}
+{-# LANGUAGE KindSignatures #-}
+{-# LANGUAGE TypeOperators #-}
+{-
+
+Exercising avoidance of known landmines.
+
+We need one each of
+
+  PostTc id Kind
+  PostTc id Type
+
+  PostRn id Fixity
+  PostRn id NameSet
+
+
+-}
+module MineKind where
+
+data HList :: [*] -> * where
+  HNil  :: HList '[]
+  HCons :: a -> HList t -> HList (a ': t)
+
+data Tuple :: (*,*) -> * where
+  Tuple :: a -> b -> Tuple '(a,b)