INSTALL.md

How to install Sail using opam

First, install opam (the OCaml package manager) if you haven't already. You can use your system's package manager e.g. sudo apt-get install opam (on Ubuntu 20.04) or follow the instructions from the opam website. The opam version must be >= 2.0; opam 1 versions are no longer supported. On older Ubuntu versions such as 18.04 you will not be able to use opam from the package manager, and will need to install it following the instructions on the opam website.

Use ocaml -version to check your OCaml version. If you have OCaml 4.08.1 or newer, that's fine, otherwise you can use opam switch to install a newer version:

opam switch create 5.1.0

and set up the environment for that OCaml version (note that older versions of opam suggest backticks instead of $(...), but it makes no difference):

eval $(opam config env)

Install system dependencies, on Ubuntu (if using WSL see the note below):

sudo apt-get install build-essential libgmp-dev z3 pkg-config

or MacOS homebrew:

xcode-select --install # if you haven't already
brew install gmp z3 pkg-config

Finally, install sail from the opam package https://opam.ocaml.org/packages/sail/ and its dependencies:

opam install sail

If all goes well then you'll have sail in your path:

which sail
sail --help

Some source files that sail uses are found at opam config var sail:share (e.g. for $include <foo.sail>) but sail should find those when it needs them.

Note for WSL (Windows subsystem for Linux) users

The version of z3 that ships in the ubuntu repositories can be quite old, and we've had reports that this can cause issues when using Sail on WSL. On WSL we recommend downloading a recent z3 release from https://github.com/Z3Prover/z3/releases rather than installing it via apt-get.

Installing development versions of Sail

Released Sail packages lag behind the latest development in the repository. If you find you need a recently added feature or bug fix you can use opam pin to install the latest version of Sail from the repository. Assuming you have previously followed the above instructions (required to install dependencies):

git clone https://github.com/rems-project/sail.git
opam pin add sail

will install from a local checkout of the Sail sources.

You can update with new changes as they are committed by pulling and reinstalling:

git pull
opam reinstall sail

To remove the pin and revert to the latest released opam package type:

opam pin remove sail

Building from source (without opam)

Note that if you are just interested in using development versions of Sail, rather than working the Sail source yourself, the above instructions using opam pin are likely better suited to your needs.

opam can be used to just install Sail's dependencies. From within the Sail root directory run:

opam install . --deps-only

Then Sail can be build manually using dune, via

dune build --release
dune install

or using the provided Makefile that calls the above commands:

make install

Some opam information

For full information see the opam documentation here. This section just describes the high level details of what you might need to know about opam when working with Sail coming from another language ecosystem.

For the most part opam works like a standard Linux package manager, such as apt-get (except for OCaml programs and libraries!). opam install <package> installs packages, opam update fetches up-to-date package information from the online opam repository, and opam upgrade upgrades any installed packages.

Where opam differs from some programming language package managers like npm or cargo is that packages are installed neither globally nor on a per-project basis, instead they are installed in switches. A switch has its own OCaml compiler version and set of libraries and executables. Earlier in this document we created a switch

opam switch create 5.1.0

but you can create your own switch

opam switch create <name> <compiler-version>

(if the compiler version is omitted the name is used as the compiler version).

When creating a new switch, or switching between them, use eval $(opam env) to update the current shell environment.

opam pin is a very flexible command that allows you to override an existing package to use a git repository directly, or force a specific version. It is best explained by the documentation here.