We need the following tools before compiling MUMPS on macOS.
Apple's Xcode Command Line Tools (CLT) include make, ar, ranlib, and Apple's implementation of BLAS and LAPACK, vecLib, within its Accelerate framework. We need those.
In the next step, we will install Homebrew, which will install CLT (if not already installed). So, nothing needs to be done here.
Xcode and CLT do not include a Fortran compiler. Here, we use Homebrew to install one; Homebrew can also be used for the optional installation of openblas and cmake below. If you already have Homebrew installed, run brew update to update it. If you don't have Homebrew installed, copy the following line and paste it in terminal.
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
Follow instructions from the script to install Homebrew and then to add it to your PATH.
If CLT was not installed prior, Homebrew will install it as part of the script above.
As described in the Homebrew installation page, this installs Homebrew to /opt/homebrew for an Apple Silicon Mac, /usr/local for an Intel Mac.
After installation, enter
brew doctor
to make sure there's no outstanding issues.
After installing Homebrew, enter
brew install gcc
in terminal. This will install the GNU compiler collection (GCC), which includes the Fortran compiler gfortran. If you already installed GCC through Homebrew before, this will update GCC to the most current stable version.
MUMPS requires the ScaLAPACK, MPI and OpenMP libraries, which can be installed via Homebrew
brew install scalapack open-mpi llvm
The clang compiler from Apple does not support OpenMP and we need to use the clang compiler from LLVM instead. After installing LLVM, enter
export PATH=/opt/homebrew/opt/llvm/bin:$PATH
to override the clang compiler from Apple.
This error occurs if you compile with the default clang compiler from Apple. Make sure you are using the clang compiler from LLVM by running the following command in terminal:
which clang
The output should be /path/to/llvm/bin/clang. If this is not the case, you need to override the clang compiler from Apple by running the following command in terminal:
export PATH=/opt/homebrew/opt/llvm/bin:$PATH
The tests in MESTI.jl/test and MESTI.jl/examples should complete in a few seconds. If the test keeps running without outputting any errors, ensure that MPI.jl is configured properly by following those steps.
Issue 3: "shmem: mmap: an error occurred while determining whether or not /var/folders/.../sm_segment.xxx could be created."
If you are using OpenMPI v5.0.3 or later, you may encounter this error while using MESTI.jl. The code can still complete but segmentation fault or deadlock may occur in some cases. If those issues occur, you can downgrade OpenMPI to v5.0.2