[GHC] #12513: Template Haskell boxes singleton unboxed tuples when splicing them

[GHC]

#12513: Template Haskell boxes singleton unboxed tuples when splicing them
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        Reporter:  RyanGlScott       |                Owner:
            Type:  bug               |               Status:  merge
        Priority:  normal            |            Milestone:  8.0.2
       Component:  Template Haskell  |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC accepts       |  Unknown/Multiple
  invalid program                    |            Test Case:  th/T12513
      Blocked By:                    |             Blocking:
 Related Tickets:  #5332             |  Differential Rev(s):  Phab:D2462
       Wiki Page:                    |
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Comment (by Ryan Scott <ryan.gl.scott@…>):

 In [changeset:"acdbd16ffca4f13cfae6eeed045a6fc5969adee2/ghc"
 acdbd16f/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="acdbd16ffca4f13cfae6eeed045a6fc5969adee2"
 Move #12403, #12513 users guide notes to 8.2.1 release notes

 The changes in #12403 and #12513 subtly changed the behavior of Template
 Haskell reification and splicing. While the old behavior was certainly
 buggy,
 it's possible that there's code in the wild that depended on the old
 behavior
 to work. To err on the side of caution, I'll postpone these changes to GHC
 8.2.1 instead of having them merged into GHC 8.0.2.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12513#comment:7>
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