Building the micro-ROS Static Library

The pre-built libmicroros.a must be generated on a Linux machine with ROS 2 Humble installed.

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Prerequisites

Select your environment below to see the setup instructions:

Option A: Native Ubuntu 22.04 / WSL2 (Recommended)

IMPORTANT: Requires a native Ubuntu 22.04 install or WSL2 with ROS 2 Humble.

```bash mkdir -p ~/microros_build && cd ~/microros_build git clone https://github.com/micro-ROS/micro_ros_stm32cubemx_utils.git cd micro_ros_stm32cubemx_utils/microros_static_library source /opt/ros/humble/setup.bash sudo apt install -y python3-colcon-common-extensions gcc-arm-none-eabi g++-arm-none-eabi ```

Option B: Docker (Mac/Windows/Linux)

TIP: Use Docker to avoid installing ROS 2 and toolchains on your host.

```bash docker run -it --rm \ -v $(pwd):/project \ microros/micro-ros-agent:humble /bin/bash # Inside container: git clone https://github.com/micro-ROS/micro_ros_stm32cubemx_utils.git ```

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Step 1: Create toolchain.cmake

Define the cross-compiler and hardware-specific flags for the Cortex-M7.

set(CMAKE_SYSTEM_NAME Generic)
set(CMAKE_CROSSCOMPILING 1)
set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
set(CMAKE_C_COMPILER arm-none-eabi-gcc)
set(CMAKE_CXX_COMPILER arm-none-eabi-g++)
set(CMAKE_C_COMPILER_WORKS 1 CACHE INTERNAL "")
set(CMAKE_CXX_COMPILER_WORKS 1 CACHE INTERNAL "")
set(FLAGS "-O2 -ffunction-sections -fdata-sections -fno-exceptions \
  -mcpu=cortex-m7 -mthumb -mfpu=fpv5-d16 -mfloat-abi=softfp \
  -nostdlib --param max-inline-insns-single=500 \
  -DCLOCK_MONOTONIC=0 \
  -D'RCUTILS_LOG_MIN_SEVERITY=RCUTILS_LOG_MIN_SEVERITY_NONE'" CACHE STRING "" FORCE)
set(CMAKE_C_FLAGS_INIT   "-std=c11 ${FLAGS} -D'__attribute__(x)='" CACHE STRING "" FORCE)
set(CMAKE_CXX_FLAGS_INIT "-std=c++11 ${FLAGS} -fno-rtti -D'__attribute__(x)='" CACHE STRING "" FORCE)
set(__BIG_ENDIAN__ 0)

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Step 2: Create colcon.meta

Optimize the RMW layers for STM32 memory constraints.

{
  "names": {
    "rcl":              { "cmake-args": ["-DBUILD_TESTING=OFF", "-DRCL_COMMAND_LINE_ENABLED=OFF", "-DRCL_LOGGING_ENABLED=OFF"] },
    "rcutils":          { "cmake-args": ["-DENABLE_TESTING=OFF", "-DRCUTILS_NO_FILESYSTEM=ON", "-DRCUTILS_NO_THREAD_SUPPORT=ON", "-DRCUTILS_NO_64_ATOMIC=ON", "-DRCUTILS_AVOID_DYNAMIC_ALLOCATION=ON"] },
    "rosidl_typesupport":{ "cmake-args": ["-DROSIDL_TYPESUPPORT_SINGLE_TYPESUPPORT=ON"] },
    "tracetools":       { "cmake-args": ["-DTRACETOOLS_DISABLED=ON", "-DTRACETOOLS_STATUS_CHECKING_TOOL=OFF"] },
    "microxrcedds_client":{ "cmake-args": ["-DUCLIENT_PIC=OFF", "-DUCLIENT_PROFILE_UDP=ON", "-DUCLIENT_PROFILE_TCP=ON", "-DUCLIENT_PROFILE_DISCOVERY=OFF", "-DUCLIENT_PROFILE_SERIAL=OFF", "-DUCLIENT_PROFILE_STREAM_FRAMING=ON", "-DUCLIENT_PROFILE_CUSTOM_TRANSPORT=ON"] },
    "rmw_microxrcedds": { "cmake-args": ["-DRMW_UXRCE_MAX_NODES=1", "-DRMW_UXRCE_MAX_PUBLISHERS=5", "-DRMW_UXRCE_MAX_SUBSCRIPTIONS=5", "-DRMW_UXRCE_MAX_SERVICES=1", "-DRMW_UXRCE_MAX_CLIENTS=1", "-DRMW_UXRCE_MAX_HISTORY=4", "-DRMW_UXRCE_TRANSPORT=custom"] }
  }
}

---

Step 3: Execute Build

colcon build --merge-install \
  --cmake-toolchain-file toolchain.cmake \
  --cmake-args -DCMAKE_BUILD_TYPE=Release

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Step 4: Transfer to Project

Extract the library and include files and copy them to the micro_ros_stm32cubemx_utils directory in your workspace.

mkdir -p ~/microros_output/libmicroros
find install -name "*.a" -exec cp {} ~/microros_output/libmicroros/ \;
cp -r install/include ~/microros_output/libmicroros/microros_include
cd ~ && tar -czvf microros_library.tar.gz microros_output

[!TIP] Use scp to transfer the .tar.gz file to your development machine if building remotely.