Build Instructions

Source releases may be obtained from the releases page.

You may also build the latest development version by cloning the git repository.

The following instructions assume that you have obtained a copy of the source, either by unpacking a release archive or cloning the git repository, and that your initial working directory contains the source code. (For release archives, this includes descending into the top level lcm-X.Y.Z subdirectory.)

Please note that these instructions refer to the latest release of LCM. As the build procedure may vary from release to release, if you are building an old release or the latest master, we recommend referring to the copy of this document (docs/content/build-instructions.md) found in your source distribution.

Installing the Python module on Unix-based systems

To build the Python module from source and install it, run:

pip3 install -v .

CMake and Meson overview for Unix-based systems

When building with CMake, CMake 3.12 or later is required. Sufficiently recent Linux distributions may provide a new enough CMake via their package managers but if they don’t it is often possible to use pip to get a more recent version.

These instructions assume that you will build in a directory named build as a direct subdirectory of the source directory, and that you will use the default generator. CMake and Meson support multiple generators and permit the build directory to be almost anywhere (although in-source builds are strongly discouraged for both and are prohibited in Meson). To users familiar with CMake, we recommend using Ninja.

A detailed description of how to use CMake or Meson is not specific to LCM and is beyond the scope of these instructions.

By default CMake and Meson are configured to produce a release build. To build with debug symbols instead, use:

cmake .. -DCMAKE_BUILD_TYPE=Debug

for CMake, and use:

meson setup build -Dbuildtype=debug

for Meson when configuring a build directory in the following sections.

Ubuntu and Debian

Required packages:

  • build-essential

  • cmake # note: if using CMake

  • meson # note: if using Meson

  • libglib2.0-dev

Optional packages (e.g., for language-specific support or building documentation):

  • default-jdk

  • libjchart2d-java # note: if not installed, jchart2d will be built from source in CMake

  • doxygen

  • liblua5.3-dev

  • lua5.3

  • python3-dev

Python packages needed for building documentation:

  • Sphinx

  • myst-parser

  • sphinx-rtd-theme

From a terminal, run the following commands for CMake:

mkdir build
cd build
cmake ..
make
sudo make install

or run the following commands for Meson:

meson setup build
cd build
meson compile
sudo meson install

OS X

There are several ways to build LCM on OS X, none of which are necessarily better than the others.

Homebrew

Install Homebrew packages (swap cmake for meson if building with Meson)

brew install glib pkg-config cmake

Install Java. Type javac in a terminal, then follow the instructions.

Download and build LCM.

For CMake, run:

mkdir build
cd build
cmake ..
make
make install

For Meson, run:

meson setup build
cd build
meson compile
meson install

Other Unix-based systems

On other POSIX.1-2001 systems (e.g., other GNU/Linux distributions, FreeBSD, Solaris, etc.) the only major requirement is to install the GLib 2.x development files and CMake. If possible, a Java development kit and Python should also be installed. Then follow the same instructions as for Ubuntu / Debian.

Post Install on Linux

In the following, replace $LCM_INSTALL_PREFIX with the prefix to which LCM was installed (by default, /usr/local), and replace $LCM_LIBRARY_DIR with the location of the LCM library, lcm.so (e.g. /usr/local/lib).

Some Linux distributions, such as Arch, do not contain the default install location (/usr/local/lib/) in the ld.so.conf search path. In this case, or if you installed LCM to a different, non-standard prefix, you may wish to create a ld.so.conf file for lcm:

echo $LCM_LIBRARY_DIR | sudo tee -a /etc/ld.so.conf.d/lcm.conf

Python users may need to add the lcm install location to Python’s site packages search path using a .pth file:

PYTHON_VERSION=$(python -c "import sys; print(\"%s.%s\" % sys.version_info[:2])")
PYTHON_USER_SITE=$(python -m site --user-site)
echo "$LCM_LIBRARY_DIR/python$PYTHON_VERSION/site-packages" > $PYTHON_USER_SITE/lcm.pth

Lua users may need to add to LUA_CPATH:

LUA_VERSION=$(lua -e "print(string.sub(_VERSION, 5))")
export LUA_CPATH=$LUA_CPATH:$LCM_LIBRARY_DIR/lua/$LUA_VERSION/?.so

If you install LCM to a non-standard location (i.e. other than the default /usr/local, other CMake projects using LCM may need help finding it. Although you can always point to the directory where lcmConfig.cmake is installed by manually setting lcm_DIR, it may be convenient to add the location to the default search paths:

export CMAKE_PREFIX_PATH=$CMAKE_PREFIX_PATH:$LCM_INSTALL_PREFIX

In addition, pkgconfig can be configured to find lcm.pc:

export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:$LCM_LIBRARY_DIR/pkgconfig

Bazel

LCM also supports Bazel for a subset of languages (C, C++, Java, Python). The Bazel build only provides libraries and command line tools; it doesn’t support building wheels or documentation.

If you are already a Bazel user this is a good option, but if not you will perhaps be happier sticking with the CMake or Meson build, explained above.

The Bazel build uses very few system packages, so most of the text above about required packages does not apply. The only required tool is a C/C++ compiler, e.g., apt install build-essential on Ubuntu and Debian. If Java will be used, a local JDK is also recommended, e.g., apt install default-jdk. See the example for details.

The Bazel build is not currently tested on Windows and is probably incomplete. We welcome contributions of build fixes (for Windows or any other problems).

To try out the Bazel build, first install bazelisk to provide bazel on your PATH and then run, e.g., bazel run //lcm-java:lcm-spy. See also the sample projct at examples/bazel for how to use LCM as a Bazel dependency.

Windows

We currently support building on windows using an MSYS2 environment as well as MSVC. Please see the appropriate section below for more information on each approach.

Using MSVC with vcpkg

Prerequisites

Warning: If the path to the LCM directory contains spaces, you may experience issues with vcpkg. It is highly recommended to work out of a directory whose path does not contain spaces.

Before starting, ensure you have installed Microsoft’s Build Tools for Visual Studio. When going through the setup, ensure you install a Desktop development with C++. All commands in this section are intended to be run from a shell set up for using MSVC (e.g. Developer PowerShell for VS 2022).

Begin by installing vcpkg. Follow the linked instructions until after you have set the environment variable VCPKG_ROOT and added vcpkg to PATH.

Warning: Ensure you are in a shell that has the above modified environment variables before proceeding!

In many cases, it is necessary to configure a newly-installed vcpkg with:

vcpkg x-update-baseline --add-initial-baseline

before proceeding.

Building

Use the Cmake preset for vcpkg to configure a build directory:

cmake --preset=vcpkg-vs

Then, it is possible to build using

cmake --build build --config Release

Last, you can run the tests via

ctest --output-on-failure --test-dir build -C Release

Building and installing the Python module

It is also possible to install the Python module using

pip install -v . --config-settings=cmake.args=--preset=vcpkg-vs

MSVC with vcpkg Errata

In some cases it can be helpful to configure a build directory using a direct cmake call, then have pip run using that build directory. If you run into any errors with the above pip install command, you could try:

Remove-Item -Path build/ -Recurse -Force
cmake --preset=vcpkg-vs
pip install -v . --config-settings=cmake.args=--preset=vcpkg-vs -Cbuild-dir=build

Another thing to watch out for is if you have installed vcpkg on your own but Visual Studio also installed an instance of vcpkg. In this case, if you’re using Developer Powershell for VS 2022 then it will overwrite certain changes you made to your environment variables (like VCPKG_ROOT or adding your instance of vcpkg to PATH). If you want to use the version of vcpkg you installed you’ll need to set those environment variables again to refer to the instance you want.

Using MSYS2

We currently support and test on an MSYS2 MINGW64 environment. To install the necessary dependencies, you can run:

pacman -S pactoys git make
pacboy -S make toolchain cmake glib2 gtest python-pip

MSYS2 Errata

There are a few things to watch out for:

  1. When installing LCM, CMake defaults to the usual Windows directories rather than the MSYS2 environment. You can use CMake’s --prefix option when installing to override this.

  2. If there is an installation of Python on the system in addition to the MSYS2 version, cmake may pick it up instead. If that is the case, it may be necessary to set -DPython_FIND_REGISTRY=NEVER or one of the other hints when configuring a build directory.

Java on Windows

The above does not result in an environment with Java. If you need the Java-dependent components of LCM (like lcm-spy or lcm-logplayer-gui), please install a JDK, delete any build directories, and run the above commands again.

Alternatively, if you just want to use Java-dependent components of LCM provided by a pre-built binary (like you get from pip install lcm, for example) then a JDK is not required but you will still need at least a JRE.