DR client crashes when calling system or CreateProcess on Win10

Hi,

After a lot of try and error I found the reason about what I explain on [this](https://groups.google.com/forum/#!topic/dynamorio-users/zTM2fS4TmJI) forum post.

It only crashes in Windows 10 (32 and 64 bits version) but **does not** crash on Windows 7.

Here you can find a simple [PoC](https://github.com/illera88/DR_static_test/tree/master/src) which can be used to test it.

Logs attached with level 3.

Regards

[crackme_xor.exe.0.8576.html.txt](https://github.com/DynamoRIO/dynamorio/files/1946591/crackme_xor.exe.0.8576.html.txt)
[log.0.8576.html.txt](https://github.com/DynamoRIO/dynamorio/files/1946592/log.0.8576.html.txt)