Compiling and Linking Overview

If your build system does not require GPUs for the build process, compilation of GPU-accelerated codes is generally expected to work well on the Aurora login nodes. If your build system does require GPUs, then currently that must be done on the compute nodes either via an interactive or batch job submission. Doing this interactively in a single-node job may be the preferred route as it also provides opportunity to quickly test the executable.

Filesystem

It is helpful to realize that currently there is a single temporary filesystem gecko mounted on the Aurora login and compute nodes available to users, where both home and project spaces reside. It is important to realize that this filesystem is not backed up and users should take care to retain copies of important files (e.g. local resources or ALCF's grand and eagle filesystems).

OneAPI Programming Environment

The oneAPI programming environment is currently the single environment for building and running software to maximally use the available hardware resources. The oneAPI environment is loaded by default for users and is principally defined by the following set of modules and related variants.

oneapi
intel_compute_runtime
mpich

Additional modules loading GNU CPU compilers and parallel application launch support (e.g. libfabric and cray-pals) are also provided in the default environment. The oneAPI environment provides C, C++, and Fortran compilers and associated MPICH MPI wrappers for building applications targeting CPUs and GPUs based on the OpenMP, SYCL, and OpenCL programming models.

mpicc - C Compiler
mpicxx - C++ Compiler (a.k.a mpic++)
mpifort - Fortran Compiler (a.k.a mpif70 & mpif90)

Compilers provided by Cray Programming Environments

The PrgEnv-gnu and PrgEnv-cray Cray programming environments are currently available as modules for users that neede them. The compilers provided by these environments do not currently support Intel GPUs and should only be used, if at all, for CPU-only code.

Mixed C/C++ & Fortran Applications

For applications consisting of a mix of programming languages that use MPI, it is important to use the same Fortran compiler for building the application as was used to build MPI because of mpi.mod (and similar) incompatibilities.

Additional software and build tools

A suite of build tools and libraries are available in the default Aurora PE environment. Users can look at the list of available modules with module avail to find build tools such as cmake.

$ module load cmake
$ cmake --version
cmake version 3.27.7