FAQ

• Help, I get this compilation error:

  catastrophic error: cannot open source file "chrono"
  #include <chrono>

  You need a C++11 capable compiler, and also a C++11 enabled standard library. For instance suppose you are using the Intel 15.0 C++ compiler with GCC 4.4 headers. The Intel 15.0 C++ compiler supports the C++11 standard, but the GCC 4.4 headers do not implement the C++11 standard library. You should install/load a newer GCC version (or just the headers). On cray machines, this can be done with module unload gcc; module load gcc/4.9.3 for instance.

• When running make test, many of the tests fail!

  The parallel execution in ctest is invoked by the MPIEXEC command as discovered by CMake. On many HPC clusters, this does not run unless it is executed from within a batch script. In this case all parallel tests will fail.

  Some MPI environments do not allow you to oversubscribe. For instance recent OpenMPI versions need the additional

  --oversubscribe 

  flag. Several tests use up to 19 mpi processes. If you have less than 19 cores in your system, and the mpi environment does not allow oversubscription, those tests will fail.