GHDL cross build scripts

This is a collection of Makefiles to build a cross compiling GHDL, currently at a basic stage and for experienced developers. The result is a GHDL binary which produces an executable for instance in a native Linux system that runs on another target, like

• Windows 32 bit (EXE)
• ARM64 architecture (under construction)

Tested platforms

• Host: x86_64 target: i686-mingw-w64-mingw32
• Host: aarch64 target: i686-mingw-w64-mingw32
• [dropped] Host: x86_64 target: i586-mingw32 Dropped due to lacking API support, use i686-mingw-w64-mingw32 instead

Preparing the Docker container

1. Generate the distribution self extractable: make -C recipes dist
2. Build the container: docker build -t ghdlcross .
3. Start it: docker run -it -w /home/build ghdlcross
4. Copy ghdlbuild_sfx.sh to /home/build/scripts in the docker container or copy & paste into the docker shell: wget section5.ch/downloads/ghdlbuild_sfx.sh && sh ghdlbuild_sfx.sh

New: You can also pull the docker container from Docker hub:

  docker pull hackfin/ghdl-cross-mingw32

Creating the configuration

The guess-config.mk script is used to guess the right configuration from /etc/issue and the machine id. If your setup is not supported, you will have to create a config.mk and specify the TESTING=1 flag with make.

When using the provided docker container, the local directory configuration will be taken from docker_config.mk, provided that the standard build user name is 'build'.

Preparing the build

New behaviour: Since local installations make life very difficult for proper reproduction, a Dockerfile is supplied for a reference building environment.

The GCC_VERSION variable is generated from the locally installed GCC.

You can of course modify this variable for testing.

Tested versions:

GCC version	Docker reference	Result
6.3.0	(Dockerfile, default)	PASS
7.2.0	(Dockerfile.gcc-7.2.0)	PASS
8.3.0	(Dockerfile, debian_buster)	PASS
7.3.0	(Docker container: reznik/gnat:gpl.2018.slim)	FAIL

It is no longer necessary to download the sources manually.

All the following make calls take place in the recipes/ directory

Source download

Covered by downloads.mk:

$ make download-all

Configuring GCC and GHDL

This can be done through the included Makefile prepare.mk:

$ make prepare

Building

Depending on whether BUILD_FROM_SANDBOX is set, a somewhat sandboxed cross compiler is used to build the GHDL target files. If a cross compiler with Ada support and the gnat tools (gnatmake, ...) including all target libraries (like mingw32 runtime) is already installed locally, leave this variable undefined.

Note: The installed compiler must have the same version as GCC_VERSION defined in config.mk. Since GNAT does not check for the proper compiler version to compile itself, compiling may fail. By default, the version installed on your system (or Docker container used) is selected.

Sandboxed cross compiler

The build rule to build and install the sandboxed compiler: This step is required on a 'bare' container created from the Dockerfile.

$ make install-sandbox

On some systems, the build process might complain about uninstalled GNAT, even though you have the gnat package installed. Try specifying the CC on the command line in this case and run the commands one by one:

$ make install-gcc CC=gcc-7
$ make install-target
...

Another classic is also, when g++ is not installed. Then you might get the /lib/cpp sanity check complaint.

Building Cross-ghdl:

$ make all-ghdl_cross

Building ghdl for native host:

Of course you can also simply build for the native host architecture.

$ make install

or build a debian package:

$ make deb

Cleaning up

This part is not very complete yet. If something goes wrong, you may want to repeat a process in particular by removing the corresponding 'stamp', e.g.:

$ rm build-gcc

Starting almost entirely from scratch:

$ make mrproper

If you change GCC_VERSION somewhere in between, behaviour is completely undefined, and the build will likely fail.