MinGW?
There are numerous changes for MSVC when the _MSC_VER macro is set, including a change to stop using asprintf in Instance.hpp.
When using MinGW instead, these macros don't get activated. Is it possible to check for the __MINGW32__ when required?
It wouldn't be everywhere _MSC_VER is used, as MinGW does provide some GCC-only features, like the ssize_t type.