2. Installation and Build Workflows

Build prerequisites

Minimum baseline:

CMake 3.20+
C++20 compiler

Optional dependencies by feature:

MPI implementation for multi-rank execution
CUDA/HIP/NCCL for GPU-accelerated paths
Python and pybind11 for Python bindings
Fortran compiler for Fortran module

Standard CMake configuration

From repo root:

cmake -S . -B build \
  -DDTL_ENABLE_MPI=OFF \
  -DDTL_BUILD_TESTS=ON
cmake --build build -j6

Common build profiles

Core C++ usage

cmake -S . -B build-core \
  -DDTL_ENABLE_MPI=OFF \
  -DDTL_BUILD_TESTS=ON
cmake --build build-core -j6

MPI-enabled profile

cmake -S . -B build-mpi \
  -DDTL_ENABLE_MPI=ON \
  -DDTL_BUILD_TESTS=ON
cmake --build build-mpi -j6

Full binding profile (C + Python + Fortran)

cmake -S . -B build-bindings \
  -DDTL_ENABLE_MPI=OFF \
  -DDTL_BUILD_C_BINDINGS=ON \
  -DDTL_BUILD_PYTHON=ON \
  -DDTL_BUILD_FORTRAN=ON \
  -DDTL_BUILD_TESTS=ON
cmake --build build-bindings -j6

Feature flags to know

DTL_ENABLE_MPI
DTL_ENABLE_CUDA
DTL_ENABLE_HIP
DTL_ENABLE_NCCL
DTL_BUILD_C_BINDINGS
DTL_BUILD_PYTHON
DTL_BUILD_FORTRAN
DTL_BUILD_DOCS

Installation and packaging notes

use CMake install/export if packaging into other projects
use spack repo add ./spack to expose the bundled Spack package
align runtime/backend flags with deployment environment
avoid enabling optional backends you cannot provision at runtime

Verification checklist

configure succeeds with expected backend summary
build succeeds with -j6
run at least smoke tests before adopting the build output

Next step

Proceed to Chapter 3 for runtime initialization and backend handling.