Errors generating while installing with ROOT dictionary

[Saumyenk]

Hi I was trying to install LCIO with ROOT dictionary on my local machine with Ubuntu-20.04, GCC-9.4.0, CMake-3.16.3, ROOT-6.24/06. I tried installing v02-15-02, v02-15-04 and v02-17 too. The same result I am getting. The commands I used are git checkout v02-17 mkdir build && cd build cmake -DBUILD_ROOTDICT=ON -D CMAKE_CXX_STANDARD=17 .. make -j 10 install I have attached the build-log and the install-log herewith. I would appreciate any help to sort these issues out.

With thanks and regards, Saumyen

build.log install.log

[andresailer]

[ 69%] generating: /home/photoniman/HEP_Packages/LCIO/build/lib/UTIL.cxx /home/photoniman/HEP_Packages/LCIO/build/lib/UTIL.h
In file included from /usr/local/include/TString.h:29,
                 from /usr/local/include/TNamed.h:26,
                 from /usr/local/include/TSystem.h:34,
                 from /home/photoniman/HEP_Packages/LCIO/src/cpp/src/EXAMPLE/lcio_io_benchmark.cc:13:
/usr/local/include/ROOT/RStringView.hxx:32:10: error: conflicting declaration of template ‘template<class _CharT, class _Traits> using basic_string_view = std::experimental::fundamentals_v1::basic_string_view<_CharT, _Traits>’
   32 |    using basic_string_view = ::std::experimental::basic_string_view<_CharT,_Traits>;
      |          ^~~~~~~~~~~~~~~~~

I think this means you are using different c++ standards to compile ROOT and LCIO. Was ROOT also compiled with c++17?

[Saumyenk]

Could you (if possible) tell me how I can check that? It was compiled long back and I didn't give much attention to that too.

Thanks a lot. Saumyen

[tmadlener]

You can do root-config --has-cxx17 to check whether it has been built with c++17.

[Saumyenk]

Thanks for the command. Yes, you are right. ROOT was installed with C++14. So now I tried installing LCIO with C++14 and it was successful. Thank you so much. Regards, Saumyen