Used cmake to build this, since it was possible to override the results of tests that required running executables. The cmake arguments are as in https://aur.archlinux.org/packages/mi/mingw-w64-hdf5/PKGBUILD with one addition to enable zlib support. For 2 additional build-time configuration files that hdf5 usually generates by running a compiled executable, I had to pre-generate the results with a local x86_64-w64-mingw32 build and include those generated sources. An alternative (used in the above-linked Arch package) would be to use wine at build time, but that would not work for 32 bit workers compiling a mingw64 package.

I'm leaving off the C++, Fortran, and MPI parts of the package for now. Neither openmpi nor mvapich2 are available as mingw packages yet.