Dificulty building ROOT on Ubuntu WSL


ROOT Version: root-6.20.04
Platform: Ubuntu 18.04.4 LTS
Compiler: GCC 7


Hi,
I am fairly new to ROOT and am trying to build it on Ubuntu WSL. I believe I have installed all the prerequisites linked at https://root.cern.ch/build-prerequisites#ubuntu.
I am getting the following error, and am hoping for some advice on how to fix it. I’m hoping to avoid using the binaries.

[ 62%] Building CXX object graf3d/g3d/CMakeFiles/Graf3d.dir/src/TXTRU.cxx.o
[ 62%] Building C object graf3d/g3d/CMakeFiles/Graf3d.dir/src/X3DBuffer.c.o
[ 62%] Linking CXX shared library ../../lib/libGraf3d.so
[ 62%] Built target Graf3d
[ 62%] Generating G__TreePlayer.cxx, ../../lib/TreePlayer.pcm
In file included from input_line_24:34:
/home/dmishins/ROOT/include/TMPWorkerTree.h:15:10: remark: building module 'MultiProc' as '/home/dmishins/ROOT/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] { ... }
tree/treeplayer/CMakeFiles/G__TreePlayer.dir/build.make:140: recipe for target 'tree/treeplayer/G__TreePlayer.cxx' failed
make[2]: *** [tree/treeplayer/G__TreePlayer.cxx] Error 1
CMakeFiles/Makefile2:23181: recipe for target 'tree/treeplayer/CMakeFiles/G__TreePlayer.dir/all' failed
make[1]: *** [tree/treeplayer/CMakeFiles/G__TreePlayer.dir/all] Error 2
Makefile:151: recipe for target 'all' failed
make: *** [all] Error 2

Thanks,
Daniel

I believe I’ve managed to solve that issue and get one step further. I had previously been running

sudo apt-get update
sudo apt-get upgrade

which apparently did not actually update all my packages for some reason.
Instead, running

sudo apt update && sudo apt dist-upgrade

caught that some of my packages were out of date. Running cmake again got me to the next error:

[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/TGLViewerBase.cxx.o
[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/TGLViewer.cxx.o
[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/TGLViewerEditor.cxx.o
[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/TGLVoxelPainter.cxx.o
[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/TGLWidget.cxx.o
[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/TH2GL.cxx.o
[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/TH3GL.cxx.o
[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/TKDEAdapter.cxx.o
[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/TKDEFGT.cxx.o
[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/TPointSet3DGL.cxx.o
[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/TX11GL.cxx.o
[ 64%] Building CXX object graf3d/gl/CMakeFiles/RGL.dir/src/gl2ps.cxx.o
[ 64%] Linking CXX shared library ../../lib/libRGL.so
[ 64%] Built target RGL
[ 64%] Generating G__EG.cxx, ../../lib/EG.pcm
In file included from input_line_24:9:
/home/dmishins/ROOT/include/TParticle.h:22:10: remark: building module 'Physics' as '/home/dmishins/ROOT/lib/Physics.pcm' [-Rmodule-build]
#include "TLorentzVector.h"
         ^
Error: Had to build non-system module Physics implicitly. You first need to
generate the dictionary for Physics or mark the C++ module as a system
module if you provided your own system modulemap file:
Physics [system] { ... }
montecarlo/eg/CMakeFiles/G__EG.dir/build.make:88: recipe for target 'montecarlo/eg/G__EG.cxx' failed
make[2]: *** [montecarlo/eg/G__EG.cxx] Error 1
CMakeFiles/Makefile2:28856: recipe for target 'montecarlo/eg/CMakeFiles/G__EG.dir/all' failed
make[1]: *** [montecarlo/eg/CMakeFiles/G__EG.dir/all] Error 2
Makefile:151: recipe for target 'all' failed
make: *** [all] Error 2

Hi @dmishins,

that’s surprising. I invite @oshadura to have a look, but in the mean time, could you post how you configured the build and also the log of the configure step?

@dmishins thank you so much for report! It is definitely looks like valid bug (missing dependencies for ROOT C++ modules). Can you tell me which CMake options you enabled please?

Checking out in code first failure root/tree/treeplayer/CMakeLists.txt at master · root-project/root · GitHub it is definitely make sense…

@bellenot @vvassilev we never tested ROOT with C++ modules on Ubuntu on Windows :smiley: https://ubuntu.com/wsl

For the second failure:

[ 64%] Generating G__EG.cxx, ../../lib/EG.pcm
In file included from input_line_24:9:
/home/dmishins/ROOT/include/TParticle.h:22:10: remark: building module 'Physics' as '/home/dmishins/ROOT/lib/Physics.pcm' [-Rmodule-build]
#include "TLorentzVector.h"
         ^

→ dependencies look correct, can you please try to make a clean build from scratch
removing files in your build directory. Thanks!

@oshadura nope, but it is supposed to be Ubuntu…

I just checked and release 6.18/04 builds fine.

I’ve just been running cmake with the default settings as described in the building root page. I believe that when I try building from scratch after deleting everything, I get back to the first error, so the second error may be a red herring.

I’m trying to rerun the build now to double check, but here are the commands I am running and the output:
EDIT: Actual output from the 6.20 build this time. Before I had pasted the wrong output.

(base) dmishins@phys-:~/NEWROOT/BUILD$ cmake ../root-6.20.04/
-- The C compiler identification is GNU 7.5.0
-- The CXX compiler identification is GNU 7.5.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Found Git: /usr/bin/git (found version "2.17.1")
-- Looking for python
-- Found PythonInterp: /home/dmishins/anaconda3/bin/python (found version "3.7.6")
-- Found PythonLibs: /home/dmishins/anaconda3/lib/libpython3.7m.so (found version "3.7.6")
-- Found NUMPY: /home/dmishins/anaconda3/lib/python3.7/site-packages/numpy/core/include (found version "1.18.1")
-- ROOT default compression algorithm: zlib
-- Found GCC. Major version 7, minor version 5
-- Looking for pthread.h
-- Looking for pthread.h - found
-- Looking for pthread_create
-- Looking for pthread_create - not found
-- Looking for pthread_create in pthreads
-- Looking for pthread_create in pthreads - not found
-- Looking for pthread_create in pthread
-- Looking for pthread_create in pthread - found
-- Found Threads: TRUE
-- Found a 64bit system
-- Found GNU compiler collection
-- Performing Test GLIBCXX_USE_CXX11_ABI
-- Performing Test GLIBCXX_USE_CXX11_ABI - Success
-- ROOT Platform: linux
-- ROOT Architecture: linuxx8664gcc
-- Build Type: Release (flags = '-O3 -DNDEBUG')
-- Compiler Flags: -O3 -DNDEBUG  -std=c++11 -Wno-implicit-fallthrough -Wno-noexcept-type -pipe  -Wshadow -Wall -W -Woverloaded-virtual -fsigned-char -pthread
-- Looking for ZLib
-- Found ZLIB: /usr/lib/x86_64-linux-gnu/libz.so (found version "1.2.11")
-- Looking for Freetype
-- Found Freetype: /usr/lib/x86_64-linux-gnu/libfreetype.so (found version "2.8.1")
-- Looking for PCRE
-- Found PCRE: /usr/include (found version "8.39")
-- Looking for LZMA
-- Could NOT find LibLZMA (missing: LIBLZMA_INCLUDE_DIR LIBLZMA_LIBRARY LIBLZMA_HAS_AUTO_DECODER LIBLZMA_HAS_EASY_ENCODER LIBLZMA_HAS_LZMA_PRESET)
-- LZMA not found. Switching on builtin_lzma option
-- Building LZMA version 5.2.4 included in ROOT itself
-- Looking for ZSTD
-- Could NOT find ZSTD (missing: ZSTD_LIBRARIES ZSTD_INCLUDE_DIR ZSTD_VERSION)
-- ZSTD not found. Switching on builtin_zstd option
-- Performing Test CXX_FLAG_STD_CPLUSPLUS11
-- Performing Test CXX_FLAG_STD_CPLUSPLUS11 - Success
-- Performing Test C_FLAG_STD_C99
-- Performing Test C_FLAG_STD_C99 - Success
-- Performing Test C_FLAG_WALL
-- Performing Test C_FLAG_WALL - Success
-- Performing Test CXX_FLAG_WALL
-- Performing Test CXX_FLAG_WALL - Success
-- Performing Test C_FLAG_WEXTRA
-- Performing Test C_FLAG_WEXTRA - Success
-- Performing Test CXX_FLAG_WEXTRA
-- Performing Test CXX_FLAG_WEXTRA - Success
-- Performing Test C_FLAG_WUNDEF
-- Performing Test C_FLAG_WUNDEF - Success
-- Performing Test CXX_FLAG_WUNDEF
-- Performing Test CXX_FLAG_WUNDEF - Success
-- Performing Test C_FLAG_WSHADOW
-- Performing Test C_FLAG_WSHADOW - Success
-- Performing Test CXX_FLAG_WSHADOW
-- Performing Test CXX_FLAG_WSHADOW - Success
-- Performing Test C_FLAG_WCAST_ALIGN
-- Performing Test C_FLAG_WCAST_ALIGN - Success
-- Performing Test CXX_FLAG_WCAST_ALIGN
-- Performing Test CXX_FLAG_WCAST_ALIGN - Success
-- Performing Test C_FLAG_WCAST_QUAL
-- Performing Test C_FLAG_WCAST_QUAL - Success
-- Performing Test CXX_FLAG_WCAST_QUAL
-- Performing Test CXX_FLAG_WCAST_QUAL - Success
-- Performing Test C_FLAG_WSTRICT_PROTOTYPES
-- Performing Test C_FLAG_WSTRICT_PROTOTYPES - Success
-- Looking for xxHash
-- Could NOT find xxHash (missing: xxHash_LIBRARY xxHash_INCLUDE_DIR)
-- xxHash not found. Switching on builtin_xxhash option
-- Looking for LZ4
-- Could NOT find LZ4 (missing: LZ4_LIBRARY LZ4_INCLUDE_DIR)
-- LZ4 not found. Switching on builtin_lz4 option
-- Looking for X11
-- Looking for XOpenDisplay in /usr/lib/x86_64-linux-gnu/libX11.so;/usr/lib/x86_64-linux-gnu/libXext.so
-- Looking for XOpenDisplay in /usr/lib/x86_64-linux-gnu/libX11.so;/usr/lib/x86_64-linux-gnu/libXext.so - found
-- Looking for gethostbyname
-- Looking for gethostbyname - found
-- Looking for connect
-- Looking for connect - found
-- Looking for remove
-- Looking for remove - found
-- Looking for shmat
-- Looking for shmat - found
-- Found X11: /usr/lib/x86_64-linux-gnu/libX11.so
-- X11_INCLUDE_DIR: /usr/include
-- X11_LIBRARIES: /usr/lib/x86_64-linux-gnu/libX11.so;/usr/lib/x86_64-linux-gnu/libXext.so
-- X11_Xpm_INCLUDE_PATH: /usr/include
-- X11_Xpm_LIB: /usr/lib/x86_64-linux-gnu/libXpm.so
-- X11_Xft_INCLUDE_PATH: /usr/include
-- X11_Xft_LIB: /usr/lib/x86_64-linux-gnu/libXft.so
-- X11_Xext_INCLUDE_PATH:
-- X11_Xext_LIB: /usr/lib/x86_64-linux-gnu/libXext.so
-- Could NOT find GIF (missing: GIF_LIBRARY GIF_INCLUDE_DIR)
-- Could NOT find TIFF (missing: TIFF_LIBRARY TIFF_INCLUDE_DIR)
-- Found PNG: /usr/lib/x86_64-linux-gnu/libpng.so (found version "1.6.34")
-- Could NOT find JPEG (missing: JPEG_LIBRARY JPEG_INCLUDE_DIR)
-- Looking for AfterImage
-- Could NOT find AfterImage (missing: AFTERIMAGE_INCLUDE_DIR AFTERIMAGE_LIBRARIES)
-- AfterImage not found. Switching on builtin_afterimage option
-- Building AfterImage library included in ROOT itself
-- Looking for GSL
-- Found PkgConfig: /usr/bin/pkg-config (found version "0.29.1")
-- Found GSL: /usr/include (found suitable version "2.4", minimum required is "1.10")
-- Looking for OpenGL
-- Found OpenGL: /usr/lib/x86_64-linux-gnu/libOpenGL.so
-- Looking for GLEW
-- Found GLEW: /usr/include
-- Looking for gl2ps
-- Could NOT find GL2PS (missing: GL2PS_LIBRARY GL2PS_INCLUDE_DIR)
-- gl2ps not found. Switching on builtin_gl2ps option
-- Looking for LibXml2
-- Found LibXml2: /usr/lib/x86_64-linux-gnu/libxml2.so (found version "2.9.4")
-- Found OpenSSL: /usr/lib/x86_64-linux-gnu/libcrypto.so (found version "1.1.1")
-- Looking for MySQL
-- Found MYSQL: /usr/include/mysql
-- Looking for Oracle
-- Oracle not found.
-- Oracle: You can specify includes: -DORACLE_PATH_INCLUDES=/usr/include/oracle/10.2.0.3/client
--    currently found includes:
-- Oracle: You can specify libs: -DORACLE_PATH_LIB=/usr/lib/oracle/10.2.0.3/client/lib
--    currently found libs: ORACLE_LIBRARY_OCCI-NOTFOUND;ORACLE_LIBRARY_CLNTSH-NOTFOUND;ORACLE_LIBRARY_LNNZ-NOTFOUND
-- Oracle not found. Switching off oracle option
-- Looking for PostgreSQL
-- Could NOT find PostgreSQL (missing: PostgreSQL_LIBRARY PostgreSQL_INCLUDE_DIR)
-- PostgreSQL not found. Switching off pgsql option
-- Looking for SQLite
-- Could NOT find Sqlite (missing: SQLITE_INCLUDE_DIR SQLITE_LIBRARIES)
-- SQLite not found. Switching off sqlite option
-- Looking for Pythia6
-- Pythia6 not found. Switching off pythia6 option
-- Looking for Pythia8
-- Could NOT find Pythia8 (missing: PYTHIA8_INCLUDE_DIR PYTHIA8_LIBRARY)
-- Pythia8 not found. Switching off pythia8 option
-- Looking for FFTW3
-- Found fftw3 includes at /usr/include
-- Found fftw3 library at /usr/lib/x86_64-linux-gnu/libfftw3.so
-- Looking for CFITSIO
-- Found CFITSIO: /usr/lib/x86_64-linux-gnu/libcfitsio.so (found version "3.43")
-- Looking for XROOTD
-- XROOTD not found. Set environment variable XRDSYS to point to your XROOTD installation
--                   Alternatively, you can also enable the option 'builtin_xrootd' to build XROOTD internally
--                   For the time being switching OFF 'xrootd' option
-- Could NOT find GFAL (missing: GFAL_INCLUDE_DIR SRM_IFCE_INCLUDE_DIR GFAL_LIBRARY)
-- GFAL library not found. Set variable GFAL_DIR to point to your gfal installation
                      and the variable SRM_IFCE_DIR to the srm_ifce installation
-- For the time being switching OFF 'gfal' option
-- Found FTGL: /usr/include
-- Checking for module 'davix>=0.6.4'
--   No package 'davix' found
-- Looking for uuid_generate_random in uuid
-- Looking for uuid_generate_random in uuid - not found
-- Could NOT find uuid (missing: UUID_INCLUDE_DIR)
-- Davix dependencies not found, switching OFF 'davix' option.
-- Looking for TBB
-- Could NOT find TBB: Found unsuitable version "2017.0", but required is at least "2018" (found /usr)
-- TBB not found, enabling 'builtin_tbb' option
-- Performing Test CXX_HAS_mno_rtm
-- Performing Test CXX_HAS_mno_rtm - Success
-- Looking for VDT
-- Could NOT find Vdt (missing: VDT_INCLUDE_DIR VDT_LIBRARY) (Required is at least version "0.4")
-- VDT not found. Ensure that the installation of VDT is in the CMAKE_PREFIX_PATH
--                Switching ON 'builtin_vdt' option
-- Cannot select cudnn without selecting cuda or tmva-gpu. Option is ignored
-- Looking for BLAS for optional parts of TMVA
-- A library with BLAS API not found. Please specify library location.
-- Using GSL CBLAS for optional parts of TMVA
-- Performing Test ROOT_HAVE_CXX_ATOMICS_WITHOUT_LIB
-- Performing Test ROOT_HAVE_CXX_ATOMICS_WITHOUT_LIB - Success
-- Building LLVM in 'Release' mode.
-- The ASM compiler identification is GNU
-- Found assembler: /usr/bin/cc
-- Looking for backtrace
-- Looking for backtrace - found
-- backtrace facility detected in default set of libraries
-- Found Backtrace: /usr/include
-- Native target architecture is X86
-- Threads disabled.
-- Doxygen disabled.
-- Go bindings disabled.
-- LLVM host triple: x86_64-unknown-linux-gnu
-- LLVM default target triple: x86_64-unknown-linux-gnu
-- Building with -fPIC
-- Constructing LLVMBuild project information
-- Linker detection: GNU ld
-- SysLibs: rt;dl;-lpthread;/usr/lib/x86_64-linux-gnu/libz.so
-- Targeting X86
-- Targeting NVPTX
-- Clang version: 5.0.0
-- Cling version (from VERSION file): ROOT_0.7~dev
-- Cling will look for C++ headers in '/usr/include/c++/7:/usr/include/x86_64-linux-gnu/c++/7:/usr/include/c++/7/backward' at runtime.
-- And then fallback to: 'x86_64-linux-gnu-g++-7'
-- Performing Test CXX_HAS_Wno_maybe_uninitialized
-- Performing Test CXX_HAS_Wno_maybe_uninitialized - Success
-- Performing Test __result
-- Performing Test __result - Success
-- Performing Test CXX_HAS_fno_rtti
-- Performing Test CXX_HAS_fno_rtti - Success
-- Performing Test C_HAS_Wno_strict_overflow
-- Performing Test C_HAS_Wno_strict_overflow - Success
-- Performing Test C_HAS_Wno_maybe_uninitialized
-- Performing Test C_HAS_Wno_maybe_uninitialized - Success
-- Performing Test C_HAS_Wno_parentheses_equality
-- Performing Test C_HAS_Wno_parentheses_equality - Success
-- Looking for m
-- Looking for m - not found
-- Performing Test CXX_HAS_fno_strict_aliasing
-- Performing Test CXX_HAS_fno_strict_aliasing - Success
-- Performing Test CXX_HAS_Wno_parentheses_equality
-- Performing Test CXX_HAS_Wno_parentheses_equality - Success
-- Performing Test CXX_HAS_Wno_cast_function_type
-- Performing Test CXX_HAS_Wno_cast_function_type - Success
-- Performing Test CXX_HAS_Wno_deprecated_register
-- Performing Test CXX_HAS_Wno_deprecated_register - Success
-- Performing Test CXX_HAS_Wno_register
-- Performing Test CXX_HAS_Wno_register - Success
-- Performing Test found_setresuid
-- Performing Test found_setresuid - Success
-- Performing Test found_stdstringview
-- Performing Test found_stdstringview - Failed
-- Performing Test found_stdexpstringview
-- Performing Test found_stdexpstringview - Failed
-- Performing Test found_stdapply
-- Performing Test found_stdapply - Failed
-- Performing Test found_stdinvoke
-- Performing Test found_stdinvoke - Failed
-- Performing Test found_stdindexsequence
-- Performing Test found_stdindexsequence - Failed
-- Performing Test found_attribute_always_inline
-- Performing Test found_attribute_always_inline - Success
-- Performing Test has_found_attribute_noinline
-- Performing Test has_found_attribute_noinline - Success
Running /home/dmishins/NEWROOT/root-6.20.04/build/unix/compiledata.sh
Making /home/dmishins/NEWROOT/BUILD/include/compiledata.h
-- Enabled support for:  asimage builtin_afterimage builtin_clang builtin_gl2ps builtin_llvm builtin_lz4 builtin_lzma builtin_tbb builtin_vdt builtin_xxhash builtin_zstd clad dataframe exceptions fftw3 fitsio gdml http imt mathmore mlp mysql opengl pyroot roofit runtime_cxxmodules shared ssl tmva tmva-cpu tmva-pymva spectrum vdt x11 xml
-- Configuring done
-- Generating done
-- Build files have been written to: /home/dmishins/NEWROOT/BUILD
(base) dmishins@phys-:~/NEWROOT/BUILD$ cmake --build .
Scanning dependencies of target AFTERIMAGE
[  0%] Creating directories for 'AFTERIMAGE'
[  0%] Performing download step for 'AFTERIMAGE'
-- AFTERIMAGE download command succeeded.  See also /home/dmishins/NEWROOT/BUILD/AFTERIMAGE-prefix/src/AFTERIMAGE-stamp/AFTERIMAGE-download-*.log
[  0%] No patch step for 'AFTERIMAGE'
[  0%] No update step for 'AFTERIMAGE'
[  0%] Performing configure step for 'AFTERIMAGE'

Rerunning the build got the first error again:

[ 62%] Building CXX object graf3d/g3d/CMakeFiles/Graf3d.dir/src/TShape.cxx.o
[ 62%] Building CXX object graf3d/g3d/CMakeFiles/Graf3d.dir/src/TSPHE.cxx.o
[ 62%] Building CXX object graf3d/g3d/CMakeFiles/Graf3d.dir/src/TTRAP.cxx.o
[ 62%] Building CXX object graf3d/g3d/CMakeFiles/Graf3d.dir/src/TTRD1.cxx.o
[ 62%] Building CXX object graf3d/g3d/CMakeFiles/Graf3d.dir/src/TTRD2.cxx.o
[ 62%] Building CXX object graf3d/g3d/CMakeFiles/Graf3d.dir/src/TTUBE.cxx.o
[ 62%] Building CXX object graf3d/g3d/CMakeFiles/Graf3d.dir/src/TTUBS.cxx.o
[ 62%] Building CXX object graf3d/g3d/CMakeFiles/Graf3d.dir/src/TView3D.cxx.o
[ 62%] Building CXX object graf3d/g3d/CMakeFiles/Graf3d.dir/src/TXTRU.cxx.o
[ 62%] Building C object graf3d/g3d/CMakeFiles/Graf3d.dir/src/X3DBuffer.c.o
[ 62%] Linking CXX shared library ../../lib/libGraf3d.so
[ 62%] Built target Graf3d
[ 62%] Generating G__TreePlayer.cxx, ../../lib/TreePlayer.pcm
In file included from input_line_24:34:
/home/dmishins/NEWROOT/BUILD/include/TMPWorkerTree.h:15:10: remark: building module 'MultiProc' as '/home/dmishins/NEWROOT/BUILD/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] { ... }
tree/treeplayer/CMakeFiles/G__TreePlayer.dir/build.make:140: recipe for target 'tree/treeplayer/G__TreePlayer.cxx' failed
make[2]: *** [tree/treeplayer/G__TreePlayer.cxx] Error 1
CMakeFiles/Makefile2:23181: recipe for target 'tree/treeplayer/CMakeFiles/G__TreePlayer.dir/all' failed
make[1]: *** [tree/treeplayer/CMakeFiles/G__TreePlayer.dir/all] Error 2
Makefile:151: recipe for target 'all' failed
make: *** [all] Error 2

Any thoughts on this? Should I submit a bug report?

You are trying to use python3 provided by “anaconda3”. This is known to break ROOT. You need to use system provided packages only.

Try to build your ROOT using: cmake --build . -- -j1

Would that make it impossible to import and use PYroot within anaconda python?
Thank you!

You can use the python3 provided by your Ubuntu.

@Axel I just installed ROOT v6.20.04 from the binary for Ubuntu 18.04 in WSL and cannot import ROOT. My impression is that python 2.7 is needed and maybe PyPy/cppyy is missing. Do I just need to build from source against py3 and all will be good?

Don’t laugh, but I’m new to ROOT because I’m finally switching from PAW. Okay, stop laughing. I’d be happy to go back to scratch and install in Windows 10 rather than WSL, but the info I found pointed to WSL. Redirect me, please if that would be a better route, i.e., via Visual Studio. I’d be happy for a pointer to the right docs and could try to go from there. Thanks!

Hi Ed,

Not laughing - welcome to ROOT! WSL isn’t the easiest of all avenues to get started with ROOT. Windows isn’t, in general.

My suspicion is that your Python isn’t coming from the WSL “universe” or is it? What does which python say on a WSL terminal prompt?

Cheers, Axel

And @bellenot might be able to help us here.

Well, I never use WSL, but AFAIK, it should be a regular Ubuntu flavor…

Python is built into my version of Ubuntu, but it is in the path only as python3, not as python. The error that occurs during “import ROOT as rt” includes a failure to find libpython2.7.so.1.0 , which is why I was wondering if this is a mismatch between the pre-built binary and my Ubuntu. I’m also not sure if I need PyPy/cppyy as a separate dependency.

I thought this was going to require building ROOT under Ubuntu / WSL, which is why I joined this thread, but I’ve got it fixed in the binary distribution, so I’ll duck out now.