[GHC] #7735: -fext-core doesn't generate .hcr when .o and .hi files are present

[GHC]

#7735: -fext-core doesn't generate .hcr when .o and .hi files are present
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Reporter:  kmels                    |          Owner:                
    Type:  bug                      |         Status:  new           
Priority:  normal                   |      Component:  External Core 
 Version:  7.6.2                    |       Keywords:                
      Os:  Linux                    |   Architecture:  x86_64 (amd64)
 Failure:  GHC doesn't work at all  |      Blockedby:                
Blocking:                           |        Related:                
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 Create a file inside a directory and compile it using -fext-core:

 {{{
 cd /tmp/
 mkdir dir
 echo "module Main where main = return ()" > dir/Main.hs
 ghc --make -fext-core dir/Main.hs
 [1 of 1] Compiling Main             ( dir/Main.hs, dir/Main.o )
 Linking dir/Main ...
 kmels at kmels-workstelle /tmp $ ls dir/
 Main  Main.hcr  Main.hi  Main.hs  Main.o
 }}}

 If the .hcr file is deleted and our program is compiled again with -fext-
 core, no .hcr file will be generated:

 {{{
 rm dir/Main.hcr
 ghc --make -fext-core dir/Main.hs
 ls dir/
 Main  Main.hi  Main.hs  Main.o
 }}}

 The file is generated if you 1. cd to dir/ and 2. ghc --make -fext-core
 Main.hs

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7735>
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