Build Issue

Protobuf (protoc) Version Conflict

Problem

When installing dependencies like ROS or OpenCV on a system (e.g., UPC), or if an older version of protoc is pre-installed, the following error might occur during pip install or cmake:

Error Message:

#error This file was generated by an older version of protoc which is

This happens because a lower-priority protoc version is being used instead of the required version.

Solution:

1. Download the Correct protoc Version

• Visit the Protobuf Releases page and download the appropriate protoc version based on your architecture:
  • For ARM (e.g., UPC): protoc-21.12-linux-aarch_64.zip
  • For x86: protoc-21.12-linux-x86_64.zip

2. Extract the Archive

• Extract the downloaded .zip file:

unzip protoc-21.12-linux-YOUR_ARCHITECTURE.zip -d protoc-21.12

3. Update PATH

• Set the extracted protoc binary directory at the beginning of your PATH environment variable:
• Replace /path/to/extracted with the actual path where the archive was extracted.
• By placing the required protoc version at the start of the PATH environment variable, the system prioritizes it over older versions already installed.

export PATH="/path/to/extracted/protoc-21.12/bin:$PATH"

• Verification
  • Run the following command to confirm the correct version of protoc is being used:

  nvidia@tegra-ubuntu:~$ protoc --version
  libprotoc 3.21.12

4. Retry Build or Installation After updating the PATH, retry the cmake or pip command. The issue should now be resolved.

CMake Preset Error

Problem:

An error occurs when running CMake with the --preset option: "The source directory does not exist."

Error Message:

user@hostname:~/project-directory$ cmake --preset conan-release
CMake Error: The source directory "/home/user/project-directory/conan-release" does not exist.
Specify --help for usage, or press the help button on the CMake GUI.

Solution:

Check CMake Version:

• This error is often caused by using an older CMake version. Ensure that your CMake version is 3.23 or higher.

cmake --version

• If the version is outdated, refer to the installation process in the CMake installation section to upgrade to the latest version.

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In most cases, the issue can be resolved by following the above steps. If the problem persists, review the following items.

Additional Checks:

• Preset Path: Make sure you are running the CMake command from the project's root directory.
• Preset Name: Verify that the preset name defined in the CMakePresets.json file is correct.
• Git Submodule: Ensure that the submodules are properly initialized when cloning the project.

git submodule update --init --recursive

References:

• For more detailed information, refer to the Building Projects Using CMake Presets documentation.