[plt-dev] MzCOM triggers error in salloc.c

I forgot to update MzCOM for a new requirement (to support futures) on
embedding MzScheme into a Windows executable.


I'll try this myself, but if you get to it first, try adding

  static __declspec(thread) void *tls_space;

to the MzCOM executable, and then put

  scheme_register_tls_space(&tls_space, 0);

before the call to scheme_main_setup() in evalLoop().


At Sun, 23 May 2010 12:12:26 +1000, Paul Steckler wrote:
> Erich Neuwirth had written to me that MzCOM from the latest PLT
> release crashed for him, so I went off to investigate.  I hadn't run
> MzCOM (or MysterX) in yonks (as they say here).
> 
> I compiled MzCOM from sources using Visual Studio 2008, no issues
> there.  I couldn't get MysterX (libmysterx)
> to compile, though.  The thought was to load MzCOM into MysterX, but
> it looked like a tough slog to fix the
> compilation errors.  So instead, I decided to write a little C++
> driver to load MzCOM.
> 
> The driver compiled fine, but the Eval method in MzCOM just hung.  I
> haven't yet looked into that.
> 
> Next, I tried call the About method.  Indeed, I saw the About box --
> but then MzCOM crashed.
> 
> The crash is due to a write-to-NULL error around line 368 of salloc.c,
> in this block:
> 
>   # elif defined(IMPLEMENT_THREAD_LOCAL_VIA_WIN_TLS)
>     *scheme_get_thread_local_variables_ptr() = vars;
> 
> Here's the driver program:
> 
> #include "stdafx.h"
> #include "mzcom.h"
> 
> int _tmain(int argc, _TCHAR* argv[])
> {
> 	CLSID clsid;
> 	IMzObj *pIMzObj;
> 
> 	CoInitialize(NULL);
> 
> 	CLSIDFromProgID(L"MzCOM.MzObj.4.2.5.0",&clsid);
> 	CoCreateInstance(clsid,NULL,CLSCTX_SERVER,IID_IMzObj, (void 
> **)&pIMzObj);
> 
> 	pIMzObj->About();
> 
> 	return 0;
> }
> 
> It's a VS2008 project, and you need to add mzcom.h and mzcom_i.c from
> the mzcom directory in
> src/worksp.
> 
> Any ideas?
> 
> -- Paul
> _________________________________________________
>   For list-related administrative tasks:
>   http://list.cs.brown.edu/mailman/listinfo/plt-dev