This is Debian packaging of the Hercules compiler provided by ETHZ.

Compiling the compiler manually
===============================

To compile the compiler, without creating the Debian package, run:

    apt install quilt cmake ninja-build python3

    git submodule update --init
    export QUILT_PATCHES=debian/patches
    export QUILT_REFRESH_ARGS="-p ab --no-timestamps --no-index"
    quilt push -a

    make
    make install

This will install the compiler and related stuff into
~/opt/hercules-compiler.

Creating Debian packages
========================

Simple method
-------------

A simple method to create a native Debian package is the following:

    apt install build-essential cmake ninja-build python3
    make create-orig-tgz
    dpkg-buildpackage -uc -us

Sbuild method - native
----------------------

You can also use the sbuild tool to create the native package. The
advantage is that the build happens in a clean environment, ensuring
that only distribution-provided packages are used for building.

Setup the sbuild chroot as documented at
https://wiki.debian.org/sbuild and then build the package with:

    make create-orig-tgz
    sbuild

Sbuild method - cross
---------------------

Cross-compilation for different architecture is more complex,
especially in case of Ubuntu Xenial. Se let's start with simpler
variant - Debian Stretch.

### Debian Stretch ###

For Debian Stretch, setup the chroot as above and install
qemu-user-static to both your host system and the build chroot:

    sudo apt-get install qemu-user-static
    sbuild-apt <chroot-name> apt-get install qemu-user-static

Then build the package with:

    make create-orig-tgz
    sbuild --host=arm64

### Ubuntu Xenial (TX2) ###

Setup the chroot as above. Ubuntu Xenial does not have
qemu-user-static package so copy the static binaries from your host:

    sudo apt-get install qemu-user-static
	cp /usr/bin/qemu-aarch64-static /path/to/your/chroot/xenaial/usr/bin

Then modify /etc/apt/sources.list to contain the URL of arm64 package
repository. This is the sources.list that I use:

    deb [arch=amd64] http://cz.archive.ubuntu.com/ubuntu xenial main universe
    deb-src http://cz.archive.ubuntu.com/ubuntu/ xenial main universe

    deb [arch=arm64] http://ports.ubuntu.com/ xenial main universe

Furthermore, Xenial has too old packages to cross build LLVM. For that
reason, we backport the following packages: `cmake_3.7.2-1` from
Debian Stretch and `ninja-build_1.8.2-1` from Debian unstable. Just
download the corresponding source packages (from e.g.
https://packages.debian.org/source/stretch/cmake) and run

    sbuild -d xenial cmake_3.7.2-1.dsc
	sbuild -d xenial ninja-build_1.8.2-1.dsc

Then install the created packages into the xenial chroot.

Then build the package by

    make create-orig-tgz
	sbuild --host=arm64 -d xenial --add-depends="libc6-dev, libstdc++-5-dev" --build-failed-commands='%s'

The `--build-failed-commands` switch ensures that a shell is run if
the build fails to allow investigating the problem.