[ANNOUNCEMENT] Updated: mingw64-{i686,x86_64}-gcc-9.2.0-2

[Steven Penny]

> The mingw-w64 cross compilers have been updated:
>
> * mingw64-i686-gcc-9.2.0-2
> * mingw64-x86_64-gcc-9.2.0-2

Regarding "g++.exe", using a file "a.cpp":

    #include <iostream>
    int main() {
       std::cout << "☺☺" << std::endl;
    }

With these items:

- Mingw compiler
- Provided by Cygwin
- cmd.exe

Produces this output:

    ���☺

Note that changing any one of those items fixes the issue. For example:

- Use Cygwin compiler instead of Mingw compiler
- Use https://github.com/mstorsjo/llvm-mingw instead of Cygwin
- Use Mintty instead of "cmd.exe"

I think something is up. If the LLVM project can produce expected results with
"cmd.exe", Cygwin should be able to as well.