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diff --git a/chromium/buildtools/third_party/libc++/trunk/docs/BuildingLibcxx.rst b/chromium/buildtools/third_party/libc++/trunk/docs/BuildingLibcxx.rst new file mode 100644 index 00000000000..f00ce4f9cff --- /dev/null +++ b/chromium/buildtools/third_party/libc++/trunk/docs/BuildingLibcxx.rst @@ -0,0 +1,306 @@ + +=============== +Building libc++ +=============== + +.. contents:: + :local: + +Getting Started +=============== + +On Mac OS 10.7 (Lion) and later, the easiest way to get this library is to install +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: + +#. Checkout LLVM: + + * ``cd where-you-want-llvm-to-live`` + * ``svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm`` + +#. Checkout libc++: + + * ``cd where-you-want-llvm-to-live`` + * ``cd llvm/projects`` + * ``svn co http://llvm.org/svn/llvm-project/libcxx/trunk libcxx`` + +#. Checkout libc++abi: + + * ``cd where-you-want-llvm-to-live`` + * ``cd llvm/projects`` + * ``svn co http://llvm.org/svn/llvm-project/libcxxabi/trunk libcxxabi`` + +#. Configure and build libc++ with libc++abi: + + CMake is the only supported configuration system. Unlike other LLVM + projects autotools is not supported for either libc++ or libc++abi. + + Clang is the preferred compiler when building and using libc++. + + * ``cd where you want to build llvm`` + * ``mkdir build`` + * ``cd build`` + * ``cmake -G <generator> [options] <path to llvm sources>`` + + For more information about configuring libc++ see :ref:`CMake Options`. + + * ``make cxx`` --- will build libc++ and libc++abi. + * ``make check-libcxx check-libcxxabi`` --- 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 <alternate libcxx>` + +#. **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-libcxx install-libcxxabi`` --- Will install the libraries and the headers + + .. warning:: + * Replacing your systems libc++ installation could render the system non-functional. + * Mac OS X will not boot without a valid copy of ``libc++.1.dylib`` in ``/usr/lib``. + + +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++ <libsupcxx>` or libcxxrt. + +It is sometimes beneficial to build outside of the LLVM tree. An out-of-tree +build would look like this: + +.. code-block:: bash + + $ cd where-you-want-libcxx-to-live + $ # Check out llvm, libc++ and libc++abi. + $ ``svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm`` + $ ``svn co http://llvm.org/svn/llvm-project/libcxx/trunk libcxx`` + $ ``svn co http://llvm.org/svn/llvm-project/libcxxabi/trunk libcxxabi`` + $ cd where-you-want-to-build + $ mkdir build && cd build + $ export CC=clang CXX=clang++ + $ cmake -DLLVM_PATH=path/to/llvm \ + -DLIBCXX_CXX_ABI=libcxxabi \ + -DLIBCXX_CXX_ABI_INCLUDE_PATHS=path/to/libcxxabi/include \ + path/to/libcxx + $ make + $ make check-libcxx # optional + + +.. _`libc++abi`: http://libcxxabi.llvm.org/ + + +.. _CMake Options: + +CMake Options +============= + +Here are some of the CMake variables that are used often, along with a +brief explanation and LLVM-specific notes. For full documentation, check the +CMake docs or execute ``cmake --help-variable VARIABLE_NAME``. + +**CMAKE_BUILD_TYPE**:STRING + Sets the build type for ``make`` based generators. Possible values are + Release, Debug, RelWithDebInfo and MinSizeRel. On systems like Visual Studio + the user sets the build type with the IDE settings. + +**CMAKE_INSTALL_PREFIX**:PATH + Path where LLVM will be installed if "make install" is invoked or the + "INSTALL" target is built. + +**CMAKE_CXX_COMPILER**:STRING + The C++ compiler to use when building and testing libc++. + + +.. _libcxx-specific options: + +libc++ specific options +----------------------- + +.. option:: LIBCXX_ENABLE_ASSERTIONS:BOOL + + **Default**: ``ON`` + + Build libc++ with assertions enabled. + +.. option:: LIBCXX_BUILD_32_BITS:BOOL + + **Default**: ``OFF`` + + Build libc++ as a 32 bit library. Also see :option:`LLVM_BUILD_32_BITS`. + +.. option:: LIBCXX_ENABLE_SHARED:BOOL + + **Default**: ``ON`` + + Build libc++ as a shared library. If ``OFF`` is specified then libc++ is + built as a static library. + +.. option:: LIBCXX_LIBDIR_SUFFIX:STRING + + Extra suffix to append to the directory where libraries are to be installed. + This option overrides :option:`LLVM_LIBDIR_SUFFIX`. + +.. _ABI Library Specific Options: + +ABI Library Specific Options +---------------------------- + +.. option:: LIBCXX_CXX_ABI:STRING + + **Values**: ``none``, ``libcxxabi``, ``libcxxrt``, ``libstdc++``, ``libsupc++``. + + Select the ABI library to build libc++ against. + +.. option:: LIBCXX_CXX_ABI_INCLUDE_PATHS:PATHS + + Provide additional search paths for the ABI library headers. + +.. option:: LIBCXX_CXX_ABI_LIBRARY_PATH:PATH + + Provide the path to the ABI library that libc++ should link against. + +.. option:: LIBCXX_ENABLE_STATIC_ABI_LIBRARY:BOOL + + **Default**: ``OFF`` + + If this option is enabled, libc++ will try and link the selected ABI library + statically. + +.. option:: LIBCXX_ENABLE_ABI_LINKER_SCRIPT:BOOL + + **Default**: ``ON`` by default on UNIX platforms other than Apple unless + 'LIBCXX_ENABLE_STATIC_ABI_LIBRARY' is ON. Otherwise the default value is ``OFF``. + + This option generate and installs a linker script as ``libc++.so`` which + links the correct ABI library. + +.. option:: LIBCXXABI_USE_LLVM_UNWINDER:BOOL + + **Default**: ``OFF`` + + Build and use the LLVM unwinder. Note: This option can only be used when + libc++abi is the C++ ABI library used. + + +libc++ Feature options +---------------------- + +.. option:: LIBCXX_ENABLE_EXCEPTIONS:BOOL + + **Default**: ``ON`` + + Build libc++ with exception support. + +.. option:: LIBCXX_ENABLE_RTTI:BOOL + + **Default**: ``ON`` + + Build libc++ with run time type information. + + +libc++ Feature options +---------------------- + +The following options allow building libc++ for a different ABI version. + +.. option:: LIBCXX_ABI_VERSION:STRING + + **Default**: ``1`` + + Defines the target ABI version of libc++. + +.. option:: LIBCXX_ABI_UNSTABLE:BOOL + + **Default**: ``OFF`` + + Build the "unstable" ABI version of libc++. Includes all ABI changing features + on top of the current stable version. + +.. _LLVM-specific variables: + +LLVM-specific options +--------------------- + +.. option:: LLVM_LIBDIR_SUFFIX:STRING + + Extra suffix to append to the directory where libraries are to be + installed. On a 64-bit architecture, one could use ``-DLLVM_LIBDIR_SUFFIX=64`` + to install libraries to ``/usr/lib64``. + +.. option:: LLVM_BUILD_32_BITS:BOOL + + Build 32-bits executables and libraries on 64-bits systems. This option is + available only on some 64-bits unix systems. Defaults to OFF. + +.. option:: LLVM_LIT_ARGS:STRING + + Arguments given to lit. ``make check`` and ``make clang-test`` are affected. + By default, ``'-sv --no-progress-bar'`` on Visual C++ and Xcode, ``'-sv'`` on + others. + + +Using Alternate ABI libraries +============================= + + +.. _libsupcxx: + +Using libsupc++ on Linux +------------------------ + +You will need libstdc++ in order to provide libsupc++. + +Figure out where the libsupc++ headers are on your system. On Ubuntu this +is ``/usr/include/c++/<version>`` and ``/usr/include/c++/<version>/<target-triple>`` + +You can also figure this out by running + +.. code-block:: bash + + $ echo | g++ -Wp,-v -x c++ - -fsyntax-only + ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu" + ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/4.7/../../../../x86_64-linux-gnu/include" + #include "..." search starts here: + #include <...> search starts here: + /usr/include/c++/4.7 + /usr/include/c++/4.7/x86_64-linux-gnu + /usr/include/c++/4.7/backward + /usr/lib/gcc/x86_64-linux-gnu/4.7/include + /usr/local/include + /usr/lib/gcc/x86_64-linux-gnu/4.7/include-fixed + /usr/include/x86_64-linux-gnu + /usr/include + End of search list. + +Note that the first two entries happen to be what we are looking for. This +may not be correct on other platforms. + +We can now run CMake: + +.. code-block:: bash + + $ CC=clang CXX=clang++ cmake -G "Unix Makefiles" \ + -DLIBCXX_CXX_ABI=libstdc++ \ + -DLIBCXX_CXX_ABI_INCLUDE_PATHS="/usr/include/c++/4.7/;/usr/include/c++/4.7/x86_64-linux-gnu/" \ + -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr \ + <libc++-source-dir> + + +You can also substitute ``-DLIBCXX_CXX_ABI=libsupc++`` +above, which will cause the library to be linked to libsupc++ instead +of libstdc++, but this is only recommended if you know that you will +never need to link against libstdc++ in the same executable as libc++. +GCC ships libsupc++ separately but only as a static library. If a +program also needs to link against libstdc++, it will provide its +own copy of libsupc++ and this can lead to subtle problems. + +.. code-block:: bash + + $ make cxx + $ make install + +You can now run clang with -stdlib=libc++. |