Building gz-sim

gz-sim follows the Gazebo project's standard build process. Two equally valid front-ends exist; pick based on what the user already has set up.

1. Direct CMake (single repo)

Assumes every Gazebo dependency (gz-cmake, gz-common, gz-physics, …) is already installed system-wide.

sh
cmake -S . -B build -G Ninja \
  -DCMAKE_BUILD_TYPE=RelWithDebInfo \
  -DBUILD_TESTING=ON
cmake --build build -j"$(nproc)"

Useful flags:

| Flag | Effect | |------|--------| | -DCMAKE_BUILD_TYPE=Debug | Asserts on, no optimization, full symbols. | | -DENABLE_PROFILER=ON | Compiles in GZ_PROFILER hooks. | | -DBUILD_TESTING=OFF | Skip test targets (faster, smaller). | | -DCMAKE_INSTALL_PREFIX=/opt/gz | Override install location. | | -DBUILD_DOCS=ON | Build Doxygen + tutorials (needs doxygen). |

Install (optional, into prefix):

sh
cmake --install build

2. colcon workspace (Gazebo source build)

When the user is building the full Gazebo stack:

sh
# from <workspace>/src/ that contains gz-sim and friends
colcon build --merge-install --cmake-args -DBUILD_TESTING=ON
source install/setup.bash

Limit to gz-sim and its deps:

sh
colcon build --merge-install \
  --packages-up-to gz-sim \
  --cmake-args -DCMAKE_BUILD_TYPE=RelWithDebInfo

Bazel (alternative)

sh
bazel build //... --config=linux
bazel test  //... --config=linux

MODULE.bazel pins the dependencies; the matrix is exercised by .github/workflows/bazel.yml.

After building

• Run the smoke test: gz sim -v 4 shapes.sdf (needs source install/setup.bash

when built via colcon).

• For headless CI, prefix with xvfb-run -s '-screen 0 1280x800x24'.
• For sanitizers, configure with -DCMAKE_CXX_FLAGS="-fsanitize=address,undefined"

and -DCMAKE_EXE_LINKER_FLAGS="-fsanitize=address,undefined".

Common failures

• find_package(gz-cmake REQUIRED) failing → user hasn't installed gz-cmake.
• Linker errors about Qt6 → ensure qt6-base-dev + qt6-declarative-dev

+ qt6-5compat-dev are present.

• Missing sdformat → install the matching libsdformat<NN>-dev for the

current Gazebo distribution (Rotary → check package.xml).

• Out-of-date gz-msgs headers → rebuild gz-msgs before gz-sim.

Always cd into the repo root (/home/rdadmin/gz-sim) before running these.