Named haddock sections, using single-line comments, no longer parsed/found in GHC HEAD (8.0)

[christiaanb]

Using doctest on GHC HEAD I discovered that named sections using single-line comment style are no longer parsed/found.

So the following works in GHC 710, but does not work in HEAD:

-- $setup
-- >>> bla bla
-- >>> har har

Named sections using multi-line comments are however parsed/found correctly. So the following works in GHC 710 and HEAD:

{- $setup
>>> bla bla
>>> har har
-}

I have no idea if this is a GHC bug or not, but I figured someone here might know.