Build and Installing ldmx-sw

There are many intricasies that come with building such a large software project. This chapter is focused on providing guides on how to accomplish this build and more detailes related to it.

This chapter assumes you already finished with everything under "Getting started"

Clone the Software Repository

In a terminal, go to the directory where you will keep all of your LDMX software and run the following command.

git clone --recursive git@github.com:LDMX-Software/ldmx-sw.git

Comments

The --recursive flag is very important because there are several necessary parts of ldmx-sw stored in separate git repositories.
The above clone uses an SSH connection which requires you to create a GitHub account and connect to it with SSH.

Changing the link after cloning

If you find yourself with an already cloned copy of ldmx-sw that was cloned with the HTTPS link and you wish to create a new branch and push, you can switch the link of the remote to the SSH version on your machine without having to re-clone.

git remote set-url origin git@github.com:LDMX-Software/ldmx-sw.git

This is especially helpful if you've already made some changes you do not want to lose.

Test

You can see the ldmx-sw software directory in your terminal.

ls
# 'ldmx-sw' is one of the entries printed
cd ldmx-sw
just
# our justfile's default recipe is to printout all the possible commands

Setup the Environment

One of the recipes within our justfile handles initializing a default environment.

just init

Comments

This command downloads the latest development image, so it may take some time (a few minutes) on the first run.
This command only needs to be done once per clone of ldmx-sw. Look at the other commands available from just for changing the environment.
On shared computing clusters, the specific filesystem configuration may not be well suited to downloading the image with the default configuration. For apptainer, be aware that you can move the directory in-which images are stored using the APPTAINER_CACHEDIR environment variable and move the directory in-which the build takes place using the TMPDIR environment variable. This is specifically an issue for SLAC's SDF and S3DF which have very small /tmp directories (what apptainer uses if TMPDIR is not defined).
- The justfile updates the default definition of APPTAINER_CACHEDIR to be the parent directory of ldmx-sw, but this may still not be the best location.

Test

You can view the environment configuration from denv.

denv config print
# detail of how the environment is configured

If you see something like "no workspace found", then something went wrong during the environment setup.

Development Cycle

The justfile contains many recipes that are helpful so inspect the output printed when just is run with no arguments to view some of them. The default build can be created with

just compile

You can pass CMake variables to the configure command (sanitizer is just an example) and then build the updated configuration.

just configure -DENABLE_SANITIZER_ADDRESS=ON 
just build

For the CLANG compiler with LTO please run

just configure-clang-lto
just build

Often you will want to recompile and run a config script.

just recompFire my-config.py [config args ...]

Running the test suite is done with

just test