Support ROOT IO for celer-g4 SD output

[pcanal]

No description provided.

[stognini]

Just tried to build this locally (on macOS, not Linux), and besides a couple basic errors that I address in #950, I also hit this one:

[496/497] Linking CXX shared library lib/libceler-g4-io.dylib
FAILED: lib/libceler-g4-io.dylib 
: && /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/c++ -Wall -Wextra -pedantic -fcolor-diagnostics -g -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX13.1.sdk -mmacosx-version-min=12.6 -dynamiclib -Wl,-headerpad_max_install_names -L/usr/local/opt/qt@5/lib   -L/Users/Shared/ornldev/code/spack/opt/spack/darwin-monterey-skylake/apple-clang-14.0.0/hwloc-2.9.1-vbhj7boo2gdj3h73a34dvvx7axzenhy6/lib -L/Users/Shared/ornldev/code/spack/opt/spack/darwin-monterey-skylake/apple-clang-14.0.0/libevent-2.1.12-tzkcxwonksly7i2r2q5hn72wxvq2345c/lib -L/Users/Shared/ornldev/code/spack/opt/spack/darwin-monterey-skylake/apple-clang-14.0.0/pmix-4.2.3-766a46zvts22uulmbkawo4jx4rzvd3bi/lib -o lib/libceler-g4-io.dylib -install_name @rpath/libceler-g4-io.dylib app/celer-g4/CMakeFiles/celer-g4-io.dir/HitClassesRootInterfaces.cxx.o app/celer-g4/CMakeFiles/celer-g4-io.dir/HitRootIO.cc.o -F/usr/local/opt/qt@5/lib -Wl,-rpath,/Users/4s2/celeritas-project/celeritas/build/lib -Wl,-rpath,/Users/4s2/programs/root/install/lib -Wl,-rpath,/Users/Shared/ornldev/code/spack/opt/spack/darwin-monterey-skylake/apple-clang-14.0.0/vecgeom-1.2.3-orw3mfmhdxminf2kla3dp4ndsz23bnry/lib -Wl,-rpath,/Users/4s2/programs/geant4/install-v1103/lib  lib/libaccel.dylib  /Users/4s2/programs/root/install/lib/libTree.so  lib/libceleritas.dylib  /Users/Shared/ornldev/code/spack/opt/spack/darwin-monterey-skylake/apple-clang-14.0.0/vecgeom-1.2.3-orw3mfmhdxminf2kla3dp4ndsz23bnry/lib/libvecgeom.dylib  lib/libcorecel.dylib  /Users/Shared/ornldev/code/spack/opt/spack/darwin-monterey-skylake/apple-clang-14.0.0/openmpi-4.1.5-lbbmodybuodqy2ot6iwaxmr3qtap3f5j/lib/libmpi.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4Tree.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4FR.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4GMocren.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4visHepRep.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4RayTracer.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4VRML.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4vis_management.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4modeling.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4interfaces.dylib  /usr/local/opt/qt@5/lib/QtWidgets.framework/QtWidgets  /usr/local/opt/qt@5/lib/QtGui.framework/QtGui  /usr/local/opt/qt@5/lib/QtCore.framework/QtCore  /Users/4s2/programs/geant4/install-v1103/lib/libG4persistency.dylib  /usr/local/lib/libxerces-c.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4error_propagation.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4readout.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4physicslists.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4tasking.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4run.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4event.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4tracking.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4parmodels.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4processes.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4analysis.dylib  /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX13.1.sdk/usr/lib/libexpat.tbd  /Users/4s2/programs/geant4/install-v1103/lib/libG4digits_hits.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4track.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4particles.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4geometry.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4materials.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4graphics_reps.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4intercoms.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4global.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4tools.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4clhep.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4zlib.dylib  /Users/4s2/programs/geant4/install-v1103/lib/libG4ptl.0.0.2.dylib  /Users/4s2/programs/root/install/lib/libMathCore.so  /Users/4s2/programs/root/install/lib/libImt.so  /Users/4s2/programs/root/install/lib/libMultiProc.so  /Users/4s2/programs/root/install/lib/libNet.so  /Users/4s2/programs/root/install/lib/libRIO.so  /Users/4s2/programs/root/install/lib/libThread.so  /Users/4s2/programs/root/install/lib/libCore.so && :
Undefined symbols for architecture x86_64:
  "celeritas::app::GlobalSetup::Instance()", referenced from:
      celeritas::app::HitRootIO::HitRootIO() in HitRootIO.cc.o
      celeritas::app::HitRootIO::WriteObject(celeritas::app::HitRootEvent*) in HitRootIO.cc.o
  "celeritas::app::SensitiveHit::allocator()", referenced from:
      celeritas::app::SensitiveHit::operator new(unsigned long) in HitClassesRootInterfaces.cxx.o
      celeritas::app::SensitiveHit::operator delete(void*) in HitClassesRootInterfaces.cxx.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
ninja: build stopped: subcommand failed.

[mrguilima]

On my MacOS, I also see the same thing as Stefano, but with two more lines:

ld: Undefined symbols:
  celeritas::app::GlobalSetup::Instance(), referenced from:
      celeritas::app::HitRootIO::HitRootIO() in HitRootIO.cc.o
      celeritas::app::HitRootIO::WriteHits(G4Event const*) in HitRootIO.cc.o
      celeritas::app::HitRootIO::WriteObject(celeritas::app::HitRootEvent*) in HitRootIO.cc.o
  celeritas::app::SensitiveHit::allocator(), referenced from:
      ROOT::new_celeritascLcLappcLcLSensitiveHit(void*) in HitClassesRootInterfaces.cxx.o.     <----
      ROOT::delete_celeritascLcLappcLcLSensitiveHit(void*) in HitClassesRootInterfaces.cxx.o. <----
      celeritas::app::SensitiveHit::operator delete(void*) in HitClassesRootInterfaces.cxx.o
      celeritas::app::SensitiveHit::~SensitiveHit() in HitClassesRootInterfaces.cxx.o
clang: error: linker command failed with exit code 1 (use -v to see invocation)

[sethrj]

@pcanal @stognini Would it be reasonable for us to have a standard "SD hit output" object that we keep in celeritas/io and use in our celer-g4 app? That could make it easier for us to, say, export hits directly from CPU through celer-sim and compare performance, in addition to making it easier to use the output from celer-g4.

[sethrj]

@pcanal @stognini This will be replaced by Stefano's work to put in a "hit output" in celeritas/io right? This was just a temporary hack to get out CMS verifiction data in time for the geant4 presentation, wasn't it?

[stognini]

I made a similar update on my branch to get a dictionary for testing my decoupling of classes/data. So we will need a dictionary anyway. I guess the question is: are we fine with the dictionary being generated this way, or is there something else planned? The main difference between here and my branch is that my HitClassesLinkDef, and therefore the final dictionary, is much simpler, with just structs with basic types.

[sethrj]

Let's stick with @stognini 's branch; simpler structs are better too. Also, didn't we discuss putting the dictionary code in celeritas/io? The way ROOT works, we kind of need the dictionaries to sit alongside the libraries, right?

[pcanal]

we kind of need the dictionaries to sit alongside the libraries, right?

Not completely necessary but much easier.