CMake Error, with ROOT v6.26/06

[QZ4869]

I first build the ROOT v6.26/06 on my ubuntu18.04
like this

git clone --branch latest-stable --depth=1 https://github.com/root-project/root.git root_src
cmake -DCMAKE_INSTALL_PREFIX=/data3/ROOT/root_install -Dall=ON /data3/ROOT/root_src/
cmake --build . --target install -j30

then, build the example with_cmake in this repository:

. /data3/ROOT/root_install/bin/thisroot.sh
git clone https://github.com/eguiraud/root_dictionaries_tutorial
mkdir root_dictionaries_tutorial/with_cmake/build
cd root_dictionaries_tutorial/with_cmake/build
cmake ../

then I get CMake Error:

-- Looking for ROOT
-- ROOT 6.26.06 found at /data3/ROOT/root_install/bin
-- Configuring done
CMake Error at /data3/ROOT/root_install/cmake/RootMacros.cmake:642 (add_custom_command):
  Error evaluating generator expression:

    $<REMOVE_DUPLICATES:$<TARGET_PROPERTY:readwrite_twoints,INTERFACE_SYSTEM_INCLUDE_DIRECTORIES>>

  Expression did not evaluate to a known generator expression
Call Stack (most recent call first):
  CMakeLists.txt:15 (ROOT_GENERATE_DICTIONARY)


CMake Error at /data3/ROOT/root_install/cmake/RootMacros.cmake:642 (add_custom_command):
  Error evaluating generator expression:

    $<REMOVE_DUPLICATES:$<TARGET_PROPERTY:readwrite_twoints,INCLUDE_DIRECTORIES>>

  Expression did not evaluate to a known generator expression
Call Stack (most recent call first):
  CMakeLists.txt:15 (ROOT_GENERATE_DICTIONARY)


CMake Error at /data3/ROOT/root_install/cmake/RootMacros.cmake:642 (add_custom_command):
  Error evaluating generator expression:

    $<REMOVE_DUPLICATES:$<TARGET_PROPERTY:readwrite_twoints,INTERFACE_SYSTEM_INCLUDE_DIRECTORIES>>

  Expression did not evaluate to a known generator expression
Call Stack (most recent call first):
  CMakeLists.txt:15 (ROOT_GENERATE_DICTIONARY)


CMake Error at /data3/ROOT/root_install/cmake/RootMacros.cmake:642 (add_custom_command):
  Error evaluating generator expression:

    $<REMOVE_DUPLICATES:$<TARGET_PROPERTY:readwrite_twoints,INCLUDE_DIRECTORIES>>

  Expression did not evaluate to a known generator expression
Call Stack (most recent call first):
  CMakeLists.txt:15 (ROOT_GENERATE_DICTIONARY)


CMake Error at /data3/ROOT/root_install/cmake/RootMacros.cmake:642 (add_custom_command):
  Error evaluating generator expression:

    $<REMOVE_DUPLICATES:$<TARGET_PROPERTY:readwrite_twoints,INTERFACE_SYSTEM_INCLUDE_DIRECTORIES>>

  Expression did not evaluate to a known generator expression
Call Stack (most recent call first):
  CMakeLists.txt:15 (ROOT_GENERATE_DICTIONARY)


CMake Error at /data3/ROOT/root_install/cmake/RootMacros.cmake:642 (add_custom_command):
  Error evaluating generator expression:

    $<REMOVE_DUPLICATES:$<TARGET_PROPERTY:readwrite_twoints,INCLUDE_DIRECTORIES>>

  Expression did not evaluate to a known generator expression
Call Stack (most recent call first):
  CMakeLists.txt:15 (ROOT_GENERATE_DICTIONARY)


-- Generating done
-- Build files have been written to: /data3/ROOT/About_Dict_Cmake/root_dictionaries_tutorial/with_cmake/build

I can continue to make and run this example, but this CMake Error makes me very comfused. I'm not familiar with CMake, so I need some help, any comment will be helpful, thanks!

By the way, it will no CMake Error if I use ROOT 6.22/06.

[eguiraud]

Hi,

it will no CMake Error if I use ROOT 6.22/06.

this suggests that ROOT v6.26/06 uses cmake features that are too new for the cmake version in Ubuntu 18.04.

You can use an older ROOT or a newer cmake/Ubuntu. I will inform the ROOT build system maintainer that we might have to increase the minimum required cmake version.

Cheers,
Enrico

[eguiraud]

By the way, what is your cmake version (cmake --version)?

[eguiraud]

Also note that Ubuntu 18.04 is end of life and it does not receive security updates anymore unless you have a paid ESM subscription: see https://ubuntu.com/about/release-cycle -- I would strongly suggest to update 😄

[QZ4869]

Hi Enrico, Thank you very much!
I changed the version of cmake from 3.10.2 to 3.24.0, it works! No more CMake Error.

By the way, I have another question want your help, if I want to generate the dynamic library for class twoints in this with_cmake example, to use it in ROOT prompt interactively, and only need one commend before use ROOT, like
export LD_LIBRARY_PATH=/data3/ROOT/root_dictionaries_tutorial/with_cmake/build/lib:$LD_LIBRARY_PATH.

If I want to do this, how can I change the CMakeLists.txt in with_cmake example.

Thanks again!

[eguiraud]

Hi @QZ4869 ,

For your latter question, please ask on https://root-forum.cern.ch -- that's the official support channel.

I'd also have a question: the first line in ROOT's main CMakeLists.txt, for the git tag v6-26-06, is cmake_minimum_required(VERSION 3.16 FATAL_ERROR). So I am surprised you could even start a build with cmake 3.10.2? Did you change that line, or what git commit were you using exactly?

[QZ4869]

I have two cmake in my ubuntu, the default is 3.10.2, I used the cmake 3.24.0 to make the root v6-26-06 before(because the cmake_minimum_required), and use the default version for this example, sorry for making you confused.

[eguiraud]

Ok, this is understood and fixed then 👍