[GHC] #13880: panic initTc: unsolved constraints

[GHC]

#13880: panic initTc: unsolved constraints
-------------------------------------+-------------------------------------
        Reporter:  vanto             |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  8.0.2
      Resolution:  duplicate         |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13106            |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by bgamari):

 * status:  new => closed
 * resolution:   => duplicate
 * related:   => #13106
 * milestone:   => 8.2.1


@@ -4,1 +4,1 @@
- {{{
+ {{{#!hs

New description:

 I'm trying to play with some piece of code in GHCi. Sorry if it's a
 duplicate bug.\\

 {{{#!hs
 {-# LANGUAGE TemplateHaskell #-}

 module Testbar where

 printf :: String -> String
 printf s = gen (parse s)

 $(printf "Error: %s at line %d")

 }}}

 {{{
 Prelude> :l testbar
 [1 of 1] Compiling Testbar          ( testbar.hs, interpreted )
 ghc.exe: panic! (the 'impossible' happened)
   (GHC version 8.0.2 for i386-unknown-mingw32):
         initTc: unsolved constraints
   WC {wc_insol =
         [W] gen_a10Q :: t_a10P[tau:1] (CHoleCan: gen)
         [W] parse_a10Z :: t_a10Y[tau:1] (CHoleCan: parse)}

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
 }}}

--

Comment:

 I believe this is a duplicate of #13106. I get a reasonable error with
 8.2.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13880#comment:1>
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