[Haskell-cafe] Why doesn't text-icu work on 64 bit Windows?

[Yitzchak Gale]

The text-icu library works fine with a 32 bit build of GHC on
Windows. But with a 64 bit build of GHC, any use of a function
from this library causes a segfault. See the issue on github for
simple instructions for how to reproduce the problem:

https://github.com/bos/text-icu/issues/12

As far as we know now, this could be caused by any of the following:

1. Some difference in the way ICU builds their DLLs for 64 bit Windows.

2. Some difference in the FFI bindings that is needed specifically
for 64 bit Windows.

3. A problem with GHC's linking on 64 bit Windows.

4. A problem with Cabal, e.g., some option or flag that needs to be
passed by default on 64 bit Windows.

This is an important (and extremely high quality, thanks to
Bryan O'Sullivan) library for the community, and very important for us,
so I'm posting about the issue here to raise visibility.
Any ideas about possible approaches to investigate or eliminate any
of the above possibilities would be highly appreciated.

Thanks,
Yitz