Package: gfortran-mingw-w64-x86-64

"gfortran-mingw-w64-x86-64" package binaries on Debian:

/usr/bin/x86_64-w64-mingw32-gfortran-posix /usr/bin/x86_64-w64-mingw32-gfortran-win32

You may install this package on Debian with apt-get install gfortran-mingw-w64-x86-64