Error: Building module 'Net' implicitly

I am trying to install Root 6-24 from source on OSX 11.4 from source. It goes smoothly enough for the majority of the build, but I eventually get the following error message

/Applications/ file: ../../../../lib/libclingUtils.a(PlatformWin.cpp.o) has no symbols
/Applications/ file: ../../../../lib/libclingUtils.a(PlatformWin.cpp.o) has no symbols
<<< cling interactive line includer >>>: **remark:** **building module 'Net' as**
Error: Building module 'Net' implicitly. If 'Net' requires a
dictionary please specify build dependency: 'G__MultiProc.cxx' depends on 'Net'.
Otherwise, specify '-mByproduct Net' to disable this diagnostic.
Error: Error loading the default rootcling header files.
make[2]: *** [core/multiproc/G__MultiProc.cxx] Error 1
make[1]: *** [core/multiproc/CMakeFiles/G__MultiProc.dir/all] Error 2
make: *** [all] Error 2

I had previously configured with

cmake -DCMAKE_INSTALL_PREFIX=/Users/reimer/Documents/local/ -Dbuiltin_glew=ON ../

and did the actual build with the command

make --build . --  -j1

my compiler is

CSI358562:buildDir reimer$ c++ -v
Apple clang version 12.0.5 (clang-1205.0.22.9)
Target: x86_64-apple-darwin20.5.0
Thread model: posix
InstalledDir: /Applications/

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_ROOT Version: 6.24
_Platform: OSX 11.4
_Compiler: Apple clang version 12.0.5 (clang-1205.0.22.9)

Hi @preimer,

Are you building root from scratch or reusing that same build directory?

The error explains that there should be a missing dependency, but I see that dependency is resolved in code: root/CMakeLists.txt at master · root-project/root · GitHub
so it should be something else…


I’m building it from scratch in a new build directory. That is, after each failed try, I learn what I can, and then I

cd …
rm -r buildDir
mkdir buildDir
cd buildDir


Hi Paul,

I just updated my OS to 11.4 and tried to build ROOT v6-24-00-patches branch and I am sorry but I can’t reproduce issue…
cc: @vvassilev

Could you run make --build . -- -j1 VERBOSE=1 and paste the full invocation of the failing command?

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