[GHC] #16219: Backpack - TH+indefinite module interface file error

[GHC]

#16219: Backpack - TH+indefinite module interface file error
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        Reporter:  lightandlight     |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.7
      Resolution:                    |             Keywords:  backpack
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D5475
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"d6d735c1114082b9e9cc1ba7da87c49f52891320/ghc"
 d6d735c1/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="d6d735c1114082b9e9cc1ba7da87c49f52891320"
 Fix #16219: TemplateHaskell causes indefinite package build error

 It should work to write an indefinite package using TemplateHaskell,
 so long as all of the actual TH code lives outside of the package.
 However, cleverness we had to build TH code even when building
 with -fno-code meant that we attempted to build object code for
 modules in an indefinite package, even when the signatures were
 not instantiated.  This patch disables said logic in the event
 that an indefinite package is being typechecked.

 Signed-off-by: Edward Z. Yang <ezyang at fb.com>

 Test Plan: validate

 Reviewers: simonpj, bgamari

 Reviewed By: bgamari

 Subscribers: rwbarton, carter

 GHC Trac Issues: #16219

 Differential Revision: https://phabricator.haskell.org/D5475
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16219#comment:13>
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