Description of problem:
ghc-8.2.2.ppc64 failed to build ghc-8.6.2 (for ghc:8.6 module) on ppc64
for Fedora 28 Modular.

Upstream bug reported: https://ghc.haskell.org/trac/ghc/ticket/15914

https://koji.fedoraproject.org/koji/taskinfo?taskID=30919315

Version-Release number of selected component (if applicable):
ghc-8.6.2-73.module_2477+224f985b

How reproducible:
100%

Steps to Reproduce:
1. build ghc:8.6 module for F28

Actual results:
:
utils/haddock/haddock-library/src/Documentation/Haddock/Types.hs:99:25: error:
    • GHC internal error: ‘TableRow’ is not in scope during type checking, but it passed the renamer
      tcl_env of environment: [aIy :-> Type variable ‘id’ = id :: k,
                               rHO :-> ATcTyCon Table :: k -> *,
                               rHP :-> APromotionErr RecDataConPE]
    • In the type ‘[TableRow id]’
      In the definition of data constructor ‘Table’
      In the data declaration for ‘Table’
   |
99 |   { tableHeaderRows :: [TableRow id]
   |                         ^^^^^^^^
utils/haddock/dist/build/haddock/autogen/Paths_haddock.hs:41:22: error:
    • Couldn't match type ‘a’ with ‘String’
      Expected type: IO a
        Actual type: IO String
    • In the first argument of ‘catchIO’, namely
        ‘(getEnv "haddock_libdir")’
      In the expression:
        catchIO (getEnv "haddock_libdir") (\ _ -> return libdir)
      In an equation for ‘getLibDir’:
          getLibDir
            = catchIO (getEnv "haddock_libdir") (\ _ -> return libdir)
   |
41 | getLibDir = catchIO (getEnv "haddock_libdir") (\_ -> return libdir)
   |                      ^^^^^^^^^^^^^^^^^^^^^^^
make[1]: *** [utils/haddock/ghc.mk:20: utils/haddock/dist/build/Documentation/Haddock/Types.dyn_o] Error 1

Expected results:
No error

Additional info:
This only happens on ppc64 (not ppc64le etc).