[GHC] #14775: GHC 8.4.1-alpha3 regression: Build error when `build-type: Custom` and `license: OtherLicense` are in the .cabal file

[GHC]

#14775: GHC 8.4.1-alpha3 regression: Build error when `build-type: Custom` and
`license: OtherLicense` are in the .cabal file
-------------------------------------+-------------------------------------
           Reporter:  asr            |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.4.1-alpha3
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 I'm getting the following error when `build-type: Custom` and `license:
 OtherLicense` are in the .cabal file:

 `Foo.cabal`:
 {{{
 name:                Foo
 version:             0.1.0.0
 license:             OtherLicense
 build-type:          Custom
 cabal-version:       >=1.10

 library
   exposed-modules:     Foo
   build-depends:       base
   default-language:    Haskell2010
 }}}

 `Foo.hs`:
 {{{#!hs
 module Foo where

 foo :: Int -> Int
 foo n = n
 }}}

 `Setup.hs`:
 {{{#!hs
 import Distribution.Simple
 main = defaultMain
 }}}

 The error:
 {{{
 $ cabal install
 Failed to install Foo-0.1.0.0
 cabal: Error: some packages failed to install:
 Foo-0.1.0.0-33ReQaKfqaD7MoDL7J5kFM failed during the final install step.
 The
 exception was:
 dieVerbatim: user error (cabal: Couldn't parse the output of 'setup
 register
 --gen-pkg-config':NoParse
 "license" 5
 )
 }}}

 `cabal-install` version:
 {{{
 $ cabal --version
 cabal-install version 2.0.0.1
 compiled using version 2.0.1.0 of the Cabal library
 }}}

 If I change the `license` field ''or'' the `build` field, the error
 disappeared. I didn't get the above error using GHC 8.4.1-alpha2.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14775>
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