Building a standalone copy of the OpenCilk runtime

These instructions assume that you are building the OpenCilk runtime system using the OpenCilk compiler.

Using Makefiles

1. If necessary, update the COMPILER_BASE variable in config.mk to point to the directory containing the OpenCilk compiler binaries, e.g., /path/to/opencilk-project/build/bin/. When it executes clang and other OpenCilk compiler binaries, the Makefile prepends this path to those binaries.
2. Run make.

To clean the build, run make clean.

Using CMake

1. Make a build directory at the top level and enter it:

$ mkdir build
$ cd build

2. Configure CMake. In particular, make sure to specify CMAKE_C_COMPILER and LLVM_CONFIG_PATH to point to the corresponding OpenCilk compiler binaries. For example:

$ cmake -DCMAKE_C_COMPILER=/path/to/opencilk-project/build/bin/clang -DLLVM_CONFIG_PATH=/path/to/opencilk-project/build/bin/llvm-config ../

3. Build the runtime:

$ cmake --build . -- -j<number of build threads>

Note: During step 2, you can specify other CMake flags at this step as well, such as CMAKE_BUILD_TYPE or CMAKE_C_FLAGS.

To clean the build, run cmake --build . --target clean from the build directory.

Linking against a standalone build of the OpenCilk runtime

The OpenCilk compiler accepts the flag --opencilk-resource-dir=/path/to/cheetah to specify where to find all relevant OpenCilk runtime files, including the runtime library, the bitcode ABI file, and associated header files. This resource directory should have include/ and lib/<target triple> as subdirectories. For example, if you built the standalone OpenCilk runtime using CMake, then pass the flag --opencilk-resource-dir=/path/to/cheetah/build to the OpenCilk compiler to link against that standalone build, e.g.,

/path/to/opencilk-project/build/bin/clang -o fib fib.c -fopencilk -O3 --opencilk-resource-dir=/path/to/cheetah/build