[GHC] #10192: Template Haskell crashes when building yesod-core package

[GHC]

#10192: Template Haskell crashes when building yesod-core package
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        Reporter:  DanielDiaz        |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.8.4
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:
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Comment (by DanielDiaz):

 Replying to [comment:1 snoyberg]:
 > Seems like the bug is that it's forcing a new installation of template-
 haskell, which isn't working. I'd recommend adding a constraint requiring
 `template-haskell installed` and see if that fixes your problem. I would
 definitely advise against such an upgrade.

 That indeed worked. I added "constraint: template-haskell installed" to my
 {{{~/.cabal/config}}} file and I built yesod-core successfully. I must
 admit I didn't knew about the constraint on installed versions. If it's
 the case that template-haskell should not be upgraded... Shouldn't this
 constraint be there by default? Or somehow enforced by any other means?

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10192#comment:2>
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