Building Gazebo Ionic + ROS 2 Integration on macOS (Apple Silicon)

This repository contains a custom source-based build of Gazebo Ionic and related Ignition/GZ libraries as submodules, created to avoid issues caused by mismatched dependency versions in Homebrew—especially protobuf.

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⚠️ Why this repository exists

While building gz-fuel-tools10 (and therefore the Gazebo Ionic stack), the following error appears:

  error: "Protobuf C++ gencode is built with an incompatible version of"
  error: "Protobuf C++ headers/runtime. See"
  error: "https://protobuf.dev/support/cross-version-runtime-guarantee/#cpp"

This originates from gz-msgs11:

  #include "google/protobuf/runtime_version.h"
  #if PROTOBUF_VERSION != 6032001
  #error "Protobuf C++ gencode is built with an incompatible version of"
  #error "Protobuf C++ headers/runtime. See"
  #error "https://protobuf.dev/support/cross-version-runtime-guarantee/#cpp"
  #endif

Gazebo Ionic currently expects Protobuf 32.1 (runtime version 6032001), but Homebrew installs Protobuf 33.1, which is ABI-incompatible.

❗ Result

gz-msgs11, Gazebo Ionic, and ros_gz_bridge fail to build.

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✔️ Solution

Instead of using the Homebrew protobuf package, uninstall or unlink it:

  brew uninstall protobuf
  # or
  brew unlink protobuf

Then build the correct protobuf version (32.1) from source, which is included in this repository under:

  dependencies/protobuf

This ensures that:

• gz-msgs11
• Gazebo Ionic dependencies
• ros_gz_bridge

are all built using the same protobuf runtime version.

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📦 Repository Structure

This repo includes:

• Gazebo Ionic source submodules (gz-math, gz-msgs11, gz-fuel-tools10, etc.)
• Patches for macOS builds
• ROS 2 integration compatibility
• Ability to build the entire stack from source without relying on Homebrew

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🔧 Build Instructions

Clone the repository with all submodules:

  git clone --recurse-submodules <this-repo>
  cd <this-repo>

Build Protobuf First:

    colcon build \
    --packages-select protobuf \
    --merge-install \
    --executor parallel --parallel-workers $(sysctl -n hw.ncpu) \
    --cmake-args -DCMAKE_TOOLCHAIN_FILE=~/kilted-ros2/src/cmake/toolchain.cmake 

Build rest of gazebo-ionic packages:

      colcon build --merge-install \
        --packages-ignore protobuf \
        --executor parallel --parallel-workers $(sysctl -n hw.ncpu) \
        --cmake-args -DCMAKE_TOOLCHAIN_FILE=~/kilted-ros2/src/cmake/toolchain.cmake 

Notes

• make sure there no trace of protobuf from homwbrew
• --merge-install simplifies linking for Gazebo + ROS 2.
• Do NOT mix Homebrew protobuf with source-built protobuf.

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🟢 Verification

After building:

  source install/setup.zsh
  gz fuel --help
  gz topic --help
  ros2 run ros_gz_bridge parameter_bridge

If these run without protobuf runtime errors, the environment is correctly configured.

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Result