[GHC] #13915: GHC 8.2 regression: "Can't find interface-file declaration" for promoted data family instance

[GHC]

#13915: GHC 8.2 regression: "Can't find interface-file declaration" for promoted
data family instance
-------------------------------------+-------------------------------------
        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  high              |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  8.2.1-rc2
      Resolution:                    |             Keywords:  TypeInType,
                                     |  TypeFamilies, Typeable
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D3759
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by Ben Gamari <ben@…>):

 In [changeset:"cc839c57ff9c80b50d39e8e2e66a18674bab3486/ghc" cc839c5/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="cc839c57ff9c80b50d39e8e2e66a18674bab3486"
 Typeable: Ensure that promoted data family instance tycons get bindings

 This fixes #13915, where the promoted tycons belonging to data family
 instances wouldn't get Typeable bindings, resulting in missing
 declarations.

 Test Plan: Validate with included testcases

 Reviewers: austin, simonpj

 Reviewed By: simonpj

 Subscribers: simonpj, RyanGlScott, rwbarton, thomie

 GHC Trac Issues: #13915

 Differential Revision: https://phabricator.haskell.org/D3759
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13915#comment:5>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler