[GHC] #14627: qAddTopDecls: can't convert top-level declarations

2 Jan 2018


      #14627: qAddTopDecls: can't convert top-level declarations
-------------------------------------+-------------------------------------
           Reporter:  tianxiaogu     |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.2.2
           Keywords:                 |  Operating System:  Linux
       Architecture:  x86_64         |   Type of failure:  Compile-time
  (amd64)                            |  crash or panic
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 The following program crashes 8.2.2 and HEAD (8.5.20171228).
 {{{#!hs
 {-# LANGUAGE TemplateHaskell #-}
 import           Language.Haskell.TH.Syntax         (addTopDecls)
 $(do
     ds <- [d| f = Bool
             |]
     addTopDecls ds
     [d| g = cab
       |])
 }}}
 Output:
 {{{
     Exception when trying to run compile-time code:
       ghc: panic! (the 'impossible' happened)
   (GHC version 8.5.20171228 for x86_64-unknown-linux):
         qAddTopDecls: can't convert top-level declarations

 Illegal variable name: ‘Bool’
 When splicing a TH declaration: f_0 = Bool
 Call stack:
     CallStack (from HasCallStack):
       callStackDoc, called at compiler/utils/Outputable.hs:1150:37 in
 ghc:Outputable
       pprPanic, called at compiler/typecheck/TcSplice.hs:886:27 in
 ghc:TcSplice

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

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14627
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