Problem building root 6.22.06 from source

Using CMAKE and the root source distribution to build the code. The build fails as per the below.

[ 54%] Building CXX object tree/tree/CMakeFiles/Tree.dir/src/TTreeRow.cxx.o

[ 54%] Building CXX object tree/tree/CMakeFiles/Tree.dir/src/TTreeSQL.cxx.o

[ 54%] Building CXX object tree/tree/CMakeFiles/Tree.dir/src/TVirtualIndex.cxx.o

[ 54%] Building CXX object tree/tree/CMakeFiles/Tree.dir/src/TVirtualTreePlayer.cxx.o

[ 54%] Linking CXX shared library …/…/lib/

[ 54%] Built target Tree

[ 54%] Generating G__TreePlayer.cxx, …/…/lib/TreePlayer.pcm

In file included from input_line_16:34:

/Users/claudeapruneau/Documents/GitHub/root/build-root-6.22.06/include/TMPWorkerTree.h:15:10: remark: building module ‘MultiProc’ as ‘/Users/claudeapruneau/Documents/GitHub/root/build-root-6.22.06/lib/MultiProc.pcm’ [-Rmodule-build]

#include “TMPWorker.h”


Error: Had to build non-system module MultiProc implicitly. You first need to

generate the dictionary for MultiProc or mark the C++ module as a system

module if you provided your own system modulemap file:

MultiProc [system] { … }

make[2]: *** [tree/treeplayer/G__TreePlayer.cxx] Error 1

make[1]: *** [tree/treeplayer/CMakeFiles/G__TreePlayer.dir/all] Error 2

make: *** [all] Error 2

Please read tips for efficient and successful posting and posting code

_ROOT Version: 6.22.06
_Platform: MacOs 11.1

Hi @cpruneau ,
I am not sure what might cause this error (@Axel @vvassilev ?) but unless you really have to, I would suggest to not build ROOT from source but instead install it through a package manager such as conda, macports or homebrew, see also .

It might also be useful if you could attach the full cmake output (configuration + build) and the full cmake commands you used.


Looks like we are missing a dependency. Could you add MultiProc to root/CMakeLists.txt at master · root-project/root · GitHub and see if that fixes it?

Hi Enrico
Thanks… I do not really have to… So I also tried to download using HomeBrew and that appears to work. The reason I got to this point is that I was trying to call MathMore Bessel function in version 6.18 and my calls were all returning zeros… Fingers crossed now…

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.