[haskell-platform] #136: Windows error: "ghci: Unable to locate ghc.exe"

[haskell-platform]

#136: Windows error: "ghci: Unable to locate ghc.exe"
-------------------------------+--------------------------------------------
 Reporter:  mcandre            |        Owner:  refold    
     Type:  defect             |       Status:  reopened  
 Priority:  major              |    Milestone:  2010.2.0.0
Component:  Windows installer  |   Resolution:            
 Keywords:                     |  
-------------------------------+--------------------------------------------
Comment (by mcandre):

 I downloaded [http://darcs.haskell.org/ghc-6.12/ghc/driver/ghci/ghci.c
 ghci.c]. There are only two entry paths to print the {{{Unable to locate
 ghc.exe}}} error message: lines 81-90 and lines 92-98.

 {{{
   /* Locate the binary we want to start up */
   if ( !SearchPath(NULL,
                    BINARY_NAME,
                    NULL,
                    dwSize,
                    (char*)binPath,
                    &szEnd) ) {
     errmsg1("%s: Unable to locate ghc.exe", argv[0]);
     return 1;
   }

   dwSize = MAX_PATH;
   /* Turn the path into short form - LFN form causes problems
      when passed in argv[0]. */
   if ( !(GetShortPathName(binPath, binPathShort, dwSize)) ) {
     errmsg1("%s: Unable to locate ghc.exe", argv[0]);
     return 1;
   }
 }}}

 There appears to be an inconsistency in the code. {{{SearchPath}}} on line
 86 casts {{{binPath}}} to a character pointer. Strangely,
 {{{GetShortPathName}}} on line 95 does not.

 According to Microsoft documentation, both functions should use
 {{{LPCTSTR}}}s; in other words, {{{TCHAR}}}s. If I'm wrong, then both
 should use char pointers. Either way, both should be passing the same
 types. But they're not.

 If the wrong type is being passed to one of these functions, then the
 functions may return {{{NULL}}}, which would result in the error being
 printed.

 Is any particular compiler used to create ghci.exe? I'm not sure if I
 should use Cygwin, MinGW, Visual Studio, or some other compilation system.

-- 
Ticket URL: <http://trac.haskell.org/haskell-platform/ticket/136#comment:13>
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