[plt-dev] MzScheme port on Windows x86_64: a report.

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Mon Jan 11 12:39:30 EST 2010

I'm impressed that you got it working, and I'd appreciate patches for
what you have so far.

To test, run


Yes, the JIT problem is surely LP64 vs. LLP64; the JIT generates 64-bit
operations for data structures that contain `long's. I think we'll
eventually have to change most `long's in the MzScheme code to some new
type that maps to `__int64' under Windows and `long' elsewhere.

The plan for MrEd is still to get rid of the current C++ code and
replace it with a new set of bindings that are implemented through the
FFI. The new bindings are implemented in a way that avoids the setjmp
problem. I hope to have that mostly working by March or so, but it's
difficult to predict.

At Mon, 11 Jan 2010 17:27:14 +0100, Gabriel Cuvillier wrote:
> Hi everyone!
> I managed to port MzScheme (CGC variant) to x86_64 on Win64 using Visual 
> Studio 2005.
> I have done this port because I want to embed a Scheme implementation 
> into a large C++ 32/64 bits app on windows, and MzScheme seems to be the 
> ONLY implementation which is both MSVC-compilable and SWIG-available! 
> (No, I don't want to use Python :)
> It is in "alpha" version, but it compiles and runs successfully on my 
> machine. The major restriction is that there is no JIT.. I wasn't able 
> to figure out why the JIT is crashing, but I suspect compatibility 
> problems with the LLP64 architecture of MSVC compilers (instead of LP64 
> used with GCC compilers).
> The main modifications are:
> -> sconfig.h: new target for WIN64 (MSC & _WIN64). Same as WIN32 but:
> 	Disable the JIT
> 	Disable the INT64_AS_LONG_LONG
> 	Disable USE_MZ_SETJMP (and remove contents in the mzsj86.c). 
> Apparently 
> it could cause problems with MrEd in the future, but seems to be ok for 
> MzScheme.
> -> Update libffi to the latest version. The main problem is with the 
> libffi version used which is not supporting win64. The latest one does, 
> and it seems to work for other projects (I think the JRuby team use it). 
> After a few headaches with the Microsoft Assembler, as well as obscure 
> defines, I finally managed to make it work.
> -> Plus a minor hacks around...
> With these actions, MzScheme compiles and runs. I still need to make a 
> lot more tests (is there any unit tests available?). There is more work 
> remaining to be done:
> -> Lots of warning because of conversion between "size_t" to "long" 
> (LLP64 vs LP64). Should not cause too much problems for now since sizes 
> are not easily above 2GB...
> -> Some warning because of conversion between "__int64" to "long" (LLP64 
> vs LP64 as always). They are more dangerous I think.
> -> Make the JIT working.
> After that, it should be possible to continue the port with MrEd (and 
> wxWidgets)...
> If someone have some hints about the JIT stuff, or general infos about 
> the best way to handle LLP64 vs LP64 (should I pass everything from 
> "long" to "long long"?), help is welcome...
> PS: apologies for my english spelling.

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