[GHC] #14808: GHC HEAD regression: GADT constructors no longer quantify tyvars in topological order

[GHC]

#14808: GHC HEAD regression: GADT constructors no longer quantify tyvars in
topological order
-------------------------------------+-------------------------------------
        Reporter:  RyanGlScott       |                Owner:  goldfire
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.6.1
       Component:  Compiler (Type    |              Version:  8.5
  checker)                           |
      Resolution:                    |             Keywords:  GADTs
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #14529, #14796    |  Differential Rev(s):  Phab:D4413
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"e7653bc3c4f57d2282e982b9eb83bd1fcbae6e30/ghc" e7653bc/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="e7653bc3c4f57d2282e982b9eb83bd1fcbae6e30"
 Wombling around in Trac #14808

 Comment:4 in Trac #14808 explains why I'm unhappy with the current
 state of affairs -- at least the lack of documentation.

 This smallpatch does nothing major:

 * adds comments
 * uses existing type synonyms more (notably FreeKiTyVarsWithDups)
 * adds another test case to T14808
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14808#comment:6>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler