=== If no file names and line numbers are shown below, one can run
            addr2line -Cpfie my_exefile my_line_address
    to convert `my_line_address` (e.g., 0x4a6b) into file name and line number.
    Or one can use amrex/Tools/Backtrace/parse_bt.py.

=== Please note that the line number reported by addr2line may not be accurate.
    One can use
            readelf -wl my_exefile | grep my_line_address'
    to find out the offset for that line.

 0: ./Castro2d.gnu.DEBUG.MPI.ex() [0x60a660]
    amrex::BLBackTrace::print_backtrace_info(_IO_FILE*)
/raid/testing/castro-gfortran/AMReX//Src/Base/AMReX_BLBackTrace.cpp:163:29

 1: ./Castro2d.gnu.DEBUG.MPI.ex() [0x60a35a]
    amrex::BLBackTrace::handler(int)
/raid/testing/castro-gfortran/AMReX//Src/Base/AMReX_BLBackTrace.cpp:71:8

 2: ./Castro2d.gnu.DEBUG.MPI.ex() [0x514c34]
    amrex::ParallelDescriptor::Abort(int, bool)
/raid/testing/castro-gfortran/AMReX//Src/Base/AMReX_ParallelDescriptor.cpp:224:22

 3: ./Castro2d.gnu.DEBUG.MPI.ex() [0x4d30c7]
    amrex::Abort(char const*)
/raid/testing/castro-gfortran/AMReX//Src/Base/AMReX.cpp:206:1

 4: ./Castro2d.gnu.DEBUG.MPI.ex() [0x700445]
    amrex::MLMG::solve(amrex::Vector<amrex::MultiFab*, std::allocator<amrex::MultiFab*> > const&, amrex::Vector<amrex::MultiFab const*, std::allocator<amrex::MultiFab const*> > const&, double, double, char const*)
/raid/testing/castro-gfortran/AMReX//Src/LinearSolvers/MLMG/AMReX_MLMG.cpp:171:41

 5: ./Castro2d.gnu.DEBUG.MPI.ex() [0x4ac222]
    Gravity::actual_solve_with_mlmg(int, int, amrex::Vector<amrex::MultiFab*, std::allocator<amrex::MultiFab*> > const&, amrex::Vector<amrex::MultiFab const*, std::allocator<amrex::MultiFab const*> > const&, amrex::Vector<std::array<amrex::MultiFab*, 2ul>, std::allocator<std::array<amrex::MultiFab*, 2ul> > > const&, amrex::Vector<amrex::MultiFab*, std::allocator<amrex::MultiFab*> > const&, amrex::MultiFab const*, double, double)
/raid/testing/castro-gfortran/Castro//Source/gravity/Gravity.cpp:2764:35

 6: ./Castro2d.gnu.DEBUG.MPI.ex() [0x4ab837]
    Gravity::solve_phi_with_mlmg(int, int, amrex::Vector<amrex::MultiFab*, std::allocator<amrex::MultiFab*> > const&, amrex::Vector<amrex::MultiFab*, std::allocator<amrex::MultiFab*> > const&, amrex::Vector<amrex::Vector<amrex::MultiFab*, std::allocator<amrex::MultiFab*> >, std::allocator<amrex::Vector<amrex::MultiFab*, std::allocator<amrex::MultiFab*> > > > const&, amrex::Vector<amrex::MultiFab*, std::allocator<amrex::MultiFab*> > const&, double)
/raid/testing/castro-gfortran/Castro//Source/gravity/Gravity.cpp:2669:34

 7: ./Castro2d.gnu.DEBUG.MPI.ex() [0x49ec49]
    Gravity::solve_for_phi(int, amrex::MultiFab&, amrex::Vector<amrex::MultiFab*, std::allocator<amrex::MultiFab*> > const&, int)
/raid/testing/castro-gfortran/Castro//Source/gravity/Gravity.cpp:441:58

 8: ./Castro2d.gnu.DEBUG.MPI.ex() [0x4c9a12]
    Castro::construct_new_gravity(int, int, double)
/raid/testing/castro-gfortran/Castro//Source/gravity/Castro_gravity.cpp:157:30

 9: ./Castro2d.gnu.DEBUG.MPI.ex() [0x438562]
    Castro::do_advance_ctu(double, double, int, int)
/raid/testing/castro-gfortran/Castro//Source/driver/Castro_advance_ctu.cpp:172:52

10: ./Castro2d.gnu.DEBUG.MPI.ex() [0x439a99]
    Castro::subcycle_advance_ctu(double, double, int, int)
/raid/testing/castro-gfortran/Castro//Source/driver/Castro_advance_ctu.cpp:482:56

11: ./Castro2d.gnu.DEBUG.MPI.ex() [0x432d4f]
    Castro::advance(double, double, int, int)
/raid/testing/castro-gfortran/Castro//Source/driver/Castro_advance.cpp:55:55

12: ./Castro2d.gnu.DEBUG.MPI.ex() [0x681635]
    amrex::Amr::timeStep(int, double, int, int, double)
/raid/testing/castro-gfortran/AMReX//Src/Amr/AMReX_Amr.cpp:2112:44

13: ./Castro2d.gnu.DEBUG.MPI.ex() [0x681dcd]
    amrex::Amr::coarseTimeStep(double)
/raid/testing/castro-gfortran/AMReX//Src/Amr/AMReX_Amr.cpp:2439:26

14: ./Castro2d.gnu.DEBUG.MPI.ex() [0x45b75b]
    main
/raid/testing/castro-gfortran/Castro//Source/driver/main.cpp:143:5

15: /lib64/libc.so.6(__libc_start_main+0xf3) [0x7ff00f183413]
    __libc_start_main
??:0

16: ./Castro2d.gnu.DEBUG.MPI.ex() [0x40b70e]
    _start
??:0