Generate sources for mozart fails on windows

[sjmackenzie]

Managed to scavenge a different windows box.

Steps to recreate:

• install deps
• fresh clone
• build

Problem:
Build fails to generate sources. Throws this error

C:\.<path>\mozart\builds\mozart2-release>make
[  2%] Built target generator
[  2%] Generate sources for mozart
make[2]: *** [vm/vm/main/mozart.gen] Error -1073741819
make[1]: *** [vm/vm/main/CMakeFiles/gensources.dir/all] Error 2
make: *** [all] Error 2

If I manually execute the generator.exe I get this:

terminate called after throwing an instance of `std::logic_error'
   what():    basic_string::_S_construct null not valid
This application has requested  the Runtime to terminate in an unusual way.
Please contact the application's support team for more information