Win32 FFI fails for some time now.
For example, load latest versions of FFI from http://source.squeak.org/FFI
Then try this snippet:

FFIPluginTests new testGenericDoubleCall.

And you'll get a segmentation fault, crash.dmp.
The latest vmI found in bintray already has the problem.

This bug delayed the Win64 squeak.stack.spur delivery, because I thought I introduced a regression somewhere...

I did not have time to check other OSes, but it would be worth trying.
(Before declaring any VM+plugins as stable...)

If someone has a way to easily dissect without precompiled artifacts, let me know.