Cannot compile the cpp examples, cmake generates "Unknown CMake command "open3d_show_and_abort_on_warning"

[Tetsujinfr]

IMPORTANT: Please use the following template to report the bug.

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Describe the bug I cannot compile the cpp examples, cmake generates an error "Unknown CMake command "open3d_show_and_abort_on_warning"

To Reproduce Steps to reproduce the behavior:

1. cd Open3D/examples/cpp/
2. mkdir build
3. cd build
4. cmake ..

Expected behavior Successful compilation of the examples, at least those which do not rely on third party dependencies like realsense stuff, if any.

Screenshots no need

Environment (please complete the following information):

• Operating system: (e.g. Ubuntu 18.04 Linux4Tegra)
• Python version: 3.6
• Open3D version: 0.12
• Is this remote workstation?: no
• How did you install Open3D?: build from source
• Compiler version (if built from source): gcc 7.5, clang 10.0

Additional context The library works successfully otherwise, e.g. I could run the gui and test all the python examples successfully.

thanks for your help.

[ssheorey]

• cd Open3D/examples/cpp/
• mkdir build
• cd build
• cmake ..

Hi @Tetsujinfr you have to configure the entire project at once and then build the specific examples that you want from the top level:

cd Open3D
mkdir build
cd build
cmake ..
make <list of examples to build>