[GHC] #1678: runIO does not catch userErrors, just causes code generation to fail silently

[GHC]

#1678: runIO does not catch userErrors, just causes code generation to fail
silently
---------------------------------+------------------------------------------
    Reporter:  greenrd           |        Owner:         
        Type:  bug               |       Status:  new    
    Priority:  normal            |    Milestone:         
   Component:  Template Haskell  |      Version:  6.7    
    Severity:  normal            |   Resolution:         
    Keywords:                    |   Difficulty:  Unknown
          Os:  Linux             |     Testcase:         
Architecture:  x86_64 (amd64)    |  
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Comment (by greenrd):

 Well, in this simple case, I get a panic from fail. (With my actual code I
 get a silent failure when compiling.)

 I expect to get an error message which mentions the error message passed
 to fail.

 {{{
 Prelude Language.Haskell.TH> $(runIO $ fail "hi")
 Loading package array-0.1 ... linking ... done.
 Loading package packedstring-0.1 ... linking ... done.
 Loading package pretty-1.0 ... linking ... done.
 Loading package containers-0.1 ... linking ... done.
 Loading package template-haskell ... linking ... done.
 ghc-6.7.20070909: panic! (the 'impossible' happened)
   (GHC version 6.7.20070909 for x86_64-unknown-linux):
         nameModule it{v aHU}

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

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1678>
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