libcufft-13-2 is part of the CUDA 13.2 release, and as such,
should NOT always roll to newer versions of the libcufft upstream.

The authoritative source for the version of the latest appropriate upstream
release for this package is a CUDA redistrib JSON file. These can be found at
https://developer.download.nvidia.com/compute/cuda/redist/redistrib_13.2.X.json
where the highest available X is the latest available release. The
"libcufft.version" key specifies the corresponding version of libcufft.

Because upstream "source" releases are actually in the form of pre-compiled
binaries, and are packaged in tarballs per-architecture, this package is a
multiple upstream tarball (MUT) package. A comprehensive set of upstream
tarballs consists of
 - a dummy empty tarball: libcufft-13-2_VERSION.orig.tar.xz
 - an amd64 tarball: libcufft-13-2_VERSION.orig-amd64.tar.xz
 - an arm64 tarball: libcufft-13-2_VERSION.orig-arm64.tar.xz

The amd64 and arm64 tarballs are downloaded from 
https://developer.download.nvidia.com/compute/cuda/redist/libcufft/linux-x86_64/
and
https://developer.download.nvidia.com/compute/cuda/redist/libcufft/linux-sbsa/
respectively, and renamed or symlinked to the appropriate form.

**IMPORTANT**: Do NOT download the arm64 tarball from
https://developer.download.nvidia.com/compute/cuda/redist/libcufft/linux-aarch64/
as these are legacy, Jetson specific binaries.

The dummy empty tarball can be generated locally, and should be 100% empty.

As these tarballs contain either nothing or primarily heavy, pre-compiled
binaries, their contents are not checked into the packaging VCS, per DEP14.

`debian/scripts/get-orig-source` (and the corresponding
`debian/rules get-orig-source`) is provided to automate downloading and
renaming upsteam tarballs, and generating the dummy tarball. It also updates
the debian/cuda-version file that tracks the version of CUDA this package
belongs to.
