diff --git a/libcxx/docs/BuildingLibcxx.rst b/libcxx/docs/BuildingLibcxx.rst --- a/libcxx/docs/BuildingLibcxx.rst +++ b/libcxx/docs/BuildingLibcxx.rst @@ -16,40 +16,44 @@ Xcode 4.2 or later. However if you want to install tip-of-trunk from here (getting the bleeding edge), read on. -The basic steps needed to build libc++ are: +The following instructions describe how to checkout, build, test and +(optionally) install libc++ and libc++abi. -#. Checkout and configure LLVM (including libc++ and libc++abi), according to the `LLVM - getting started `_ documentation. Make sure - to include ``libcxx`` and ``libcxxabi`` in the ``LLVM_ENABLE_PROJECTS`` option passed - to CMake. +If your system already provides a libc++ installation it is important to be +careful not to replace it. Remember Use the CMake option +``CMAKE_INSTALL_PREFIX`` to select a safe place to install libc++. - For more information about configuring libc++ see :ref:`CMake Options`. - - * ``make cxx`` --- will build libc++ and libc++abi. - * ``make check-cxx check-cxxabi`` --- will run the test suites. - - Shared libraries for libc++ and libc++ abi should now be present in llvm/build/lib. - See :ref:`using an alternate libc++ installation ` - -#. **Optional**: Install libc++ and libc++abi - - If your system already provides a libc++ installation it is important to be - careful not to replace it. Remember Use the CMake option ``CMAKE_INSTALL_PREFIX`` to - select a safe place to install libc++. - - * ``make install-cxx install-cxxabi`` --- Will install the libraries and the headers +.. warning:: + * Replacing your systems libc++ installation could render the system non-functional. + * macOS will not boot without a valid copy of ``libc++.1.dylib`` in ``/usr/lib``. - .. warning:: - * Replacing your systems libc++ installation could render the system non-functional. - * macOS will not boot without a valid copy of ``libc++.1.dylib`` in ``/usr/lib``. +.. code-block:: bash + $ git clone https://github.com/llvm/llvm-project.git + $ cd llvm-project + $ mkdir build && cd build + $ cmake -DCMAKE_C_COMPILER=clang \ + -DCMAKE_CXX_COMPILER=clang++ \ + -DLLVM_ENABLE_PROJECTS="libcxx;libcxxabi" \ + ../llvm + $ make # Build + $ make check-cxx # Test + $ make install-cxx install-cxxabi # Install + +For more information about configuring libc++ see :ref:`CMake Options`. You may +also want to read the `LLVM getting started +`_ documentation. + +Shared libraries for libc++ and libc++ abi should now be present in +``build/lib``. See :ref:`using an alternate libc++ installation ` for information on how to use this libc++. The instructions are for building libc++ on FreeBSD, Linux, or Mac using `libc++abi`_ as the C++ ABI library. On Linux, it is also possible to use :ref:`libsupc++ ` or libcxxrt. -It is sometimes beneficial to build separately from the full LLVM build. An -out-of-tree build would look like this: +It is possible to keep your LLVM and libc++ trees separate so you can avoid +rebuilding LLVM as often. An out-of-tree build would look like this: .. code-block:: bash