[libcxx] Add new Sphinx documentation

[EricWF]

Summary

This patch adds Sphinx based documentation to libc++. The goal is to make it easier to write documentation for libc++ since writing new documentation in HTML is cumbersome. This patch rewrites the main page for libc++ along with the instructions for using, building and testing libc++.

The built documentation can be found and reviewed here: http://efcs.ca/libcxx-docs

In order to build the sphinx documentation you need to specify the cmake options -DLLVM_ENABLE_SPHINX=ON -DLIBCXX_INCLUDE_DOCS=ON. This will add the makefile rule docs-libcxx-html.

[silvas]

From a Sphinx perspective, this looks fine to me. You may want to consider using html_theme = 'haiku' for consistency with clang, but reusing LLVM's is fine. (the reason I had clang use 'haiku' is that it is a bit better put together since it ships with sphinx (llvm's theme also has a notorious problem distinguishing different header levels); 'haiku' also doesn't require any static theme-related assets to be checked in since sphinx has them already as part of its own installation)

[EricWF]

In D12129#227320, @silvas wrote:

From a Sphinx perspective, this looks fine to me. You may want to consider using html_theme = 'haiku' for consistency with clang, but reusing LLVM's is fine. (the reason I had clang use 'haiku' is that it is a bit better put together since it ships with sphinx (llvm's theme also has a notorious problem distinguishing different header levels); 'haiku' also doesn't require any static theme-related assets to be checked in since sphinx has them already as part of its own installation)

I'll take a look at using clang's theme and see what comes out. Ironically I think I chose LLVM's theme because I preferred the way it distinguished between headers levels (although I have noticed some issues distinguishing nested levels). It would be nice to remove some assets from the repository.

[EricWF]

I've uploaded a version of the docs built with the "haiku" theme to http://efcs.ca/libcxx-haiku-docs. I would like other's input on which style they prefer (Note: The LLVM themed docs are here http://efcs.ca/libcxx-docs).

[EricWF]

Gentle ping. There is going to be a couple of days lag time between committing this and it showing up at libcxx.llvm.org/docs.
Once it is available at libcxx.llvm.org/docs we still have time to review it before we link to it from the homepage.
For this reason, and because the sphinx bits already got a thumbs up I would like to commit this now.

Plus I think the documentation is better reviewed in its generated form and not it's as plaintext.

@mclow.lists Would you have an objection to this approach?

NOTE: This patch does not change libcxx.llvm.org page or any existing documentation.

[jroelofs]

Both styles look ok to me, with a slight preference toward matching clang's.

docs/BuildingLibcxx.rst

56

Is there a way to make this more prominent, perhaps by putting it in a red box? This is a very important detail that is very painful to recover from if you miss it.

243

s/Note the/Note that the/

docs/index.rst

87

Should we mention the unwinders used/supported here too?

[danalbert]

I think I prefer the haiku style, but I couldn't give you any concrete reasons for that.

[EricWF]

Address review comments.

docs/BuildingLibcxx.rst

56

I'll make it happen. I was also thinking about adding loud CMake warnings whenever CMake tries to install libc++ to /usr on OS X.

docs/index.rst

87

Sure but can we do that later? I have no clue what platforms support what and I would have to get some input on that.

[jroelofs]

docs/BuildingLibcxx.rst

58

I feel like a warning is not enough... perhaps a hard error, with a message that says something like: "If you're really really sure you know what you're doing, add -DLIBCXX_OVERRIDE_DARWIN_INSTALL=YES to silence this message"?

docs/index.rst

89

Yeah. This is good for now. I just wanted to mention it while I was thinking of it.

[silvas]

docs/BuildingLibcxx.rst

58

FYI, Sphinx has some directives designed for prominent warnings like this: http://docutils.sourceforge.net/docs/ref/rst/directives.html#danger

Should render similar to the "Warning" box on http://clang.llvm.org/docs/ReleaseNotes.html (see clang/docs/ReleaseNotes.rst)

[silvas]

docs/BuildingLibcxx.rst

58

The general names for these things are "admonitions" and there are e.g. 'note' 'danger' 'warning' etc. that are hopefully appropriately styled by the theme.

CMakeLists.txt

 option(LIBCXX_ENABLE_SHARED "Build libc++ as a shared library." ON)
 
 option(LIBCXX_INCLUDE_TESTS "Build the libc++ tests." ${LLVM_INCLUDE_TESTS})
+option(LIBCXX_INCLUDE_DOCS "Build the libc++ documentation." ${LLVM_INCLUDE_DOCS})
 set(LIBCXX_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}" CACHE STRING
     "Define suffix of library directory name (32/64)")
 option(LIBCXX_INSTALL_HEADERS "Install the libc++ headers." ON)

 include_directories(include)
 add_subdirectory(include)
 add_subdirectory(lib)
+
 if (LIBCXX_INCLUDE_TESTS)
   add_subdirectory(test)
 endif()
+if (LIBCXX_INCLUDE_DOCS)
+  add_subdirectory(docs)
+endif()

cmake/Modules/HandleOutOfTreeLLVM.cmake

   if (NOT DEFINED LLVM_INCLUDE_TESTS)
     set(LLVM_INCLUDE_TESTS ${LLVM_FOUND})
   endif()
+  if (NOT DEFINED LLVM_ENABLE_SPHINX)
+    set(LLVM_ENABLE_SPHINX OFF)
+  endif()
 
   # Required LIT Configuration ------------------------------------------------
   # Define the default arguments to use with 'lit', and an option for the user

     set(cmake_3_2_USES_TERMINAL USES_TERMINAL)
   endif()
 
+  # Required doc configuration
+  if (LLVM_ENABLE_SPHINX)
+    message(STATUS "Sphinx enabled.")
+    find_package(Sphinx REQUIRED)
+  else()
+    message(STATUS "Sphinx disabled.")
+  endif()
+
   # Add LLVM Functions --------------------------------------------------------
   include(AddLLVM OPTIONAL)
 endif()

cmake/config-ix.cmake

 check_library_exists(m ccos "" LIBCXX_HAS_M_LIB)
 check_library_exists(rt clock_gettime "" LIBCXX_HAS_RT_LIB)
 check_library_exists(gcc_s __gcc_personality_v0 "" LIBCXX_HAS_GCC_S_LIB)
-

docs/BuildingLibcxx.rst

+
+===============
+Building libc++
+===============
+
+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.  However, be warned that Mac OS
+10.7 will not boot without a valid copy of ``libc++.1.dylib`` in ``/usr/lib``.
+
+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/tools``
+   * ``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/libc++abi libc++abi``
+
+#. Configure and build libc++ with libc++abi:
+
+   `CMake <CMake.html>`_ 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. Note
+that it is safest to use this from its current location rather than
+replacing your system's libc++ (if it has one, if not, go right ahead).
+See :ref:`using an alternate libc++ installation <alternate libcxx>`
+
+Mac users, remember to be careful when replacing the system's libc++.
+**Your system will not be able to boot without a functioning 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++ <libsupcxx>` or libcxxrt.
+
+It is sometimes beneficial to build outside of the LLVM tree. To build
+libc++ TODO
+
+.. 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:: 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.
+
+.. _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 &lt;...&gt; 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 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++.
 No newline at end of file

docs/CMakeLists.txt

+
+if (LLVM_ENABLE_SPHINX)
+  if (SPHINX_FOUND)
+    include(AddSphinxTarget)
+    if (${SPHINX_OUTPUT_HTML})
+      add_sphinx_target(html libcxx)
+    endif()
+  endif()
+endif()
 No newline at end of file

docs/README.txt

+libc++ Documentation
+====================
+
+The libc++ documentation is written using the Sphinx documentation generator. It is
+currently tested with Sphinx 1.1.3.
+
+To build the documents into html configure libc++ with the following cmake options:
+
+  * -DLLVM_ENABLE_SPHINX=ON
+  * -DLIBCXX_INCLUDE_DOCS=ON
+
+After configuring libc++ with these options the make rule `docs-libcxx-html`
+should be available.

docs/TestingLibcxx.rst

+==============
+Testing libc++
+==============
+
+Getting Started
+===============
+
+libc++ uses LIT to configure and run its tests. The primary way to run the
+libc++ tests is by using make check-libcxx. However since libc++ can be used
+in any number of possible configurations it is important to customize the way
+LIT builds and runs the tests. This guide provides information on how to use
+LIT directly to test libc++.
+
+Please see the `Lit Command Guide`_ for more information about LIT.
+
+.. _LIT Command Guide: http://llvm.org/docs/CommandGuide/lit.html
+
+
+Setting up the Environment
+--------------------------
+
+After building libc++ you must setup your environment to test libc++ using
+LIT.
+
+#. Create a shortcut to the actual lit executable so that you can invoke it
+   easily from the command line.
+
+   .. code-block:: bash
+
+     $ alias lit='python path/to/llvm/utils/lit/lit.py'
+
+#. Tell LIT where to find your build configuration.
+
+   .. code-block:: bash
+
+     $ export LIBCXX_SITE_CONFIG=path/to/build-libcxx/test/lit.site.cfg
+
+
+LIT Options
+===========
+
+:program:`lit` [*options*...] [*filenames*...]
+
+Options
+-------
+
+To use these options you pass them on the LIT command line as --param NAME or
+--param NAME=VALUE. Some options have default values specified during CMake's
+configuration. Passing the option on the command line will override the default.
+
+.. program:: lit
+
+.. option:: libcxx_site_config=<path/to/lit.site.cfg>
+
+  Specify the site configuration to use when running the tests.  This option
+  overrides the enviroment variable LIBCXX_SITE_CONFIG.
+
+.. option:: libcxx_headers=<path/to/headers>
+
+  Specify the libc++ headers that are tested. By default the headers in the
+  source tree are used.
+
+.. option:: libcxx_library=<path/to/libc++.so>
+
+  Specify the libc++ library that is tested. By default the library in the
+  build directory is used. This option cannot be used when use_system_lib is
+  provided.
+
+.. option:: use_system_lib=<bool>
+
+  **Default**: False
+
+  Enable or disable testing against the installed version of libc++ library.
+  Note: This does not use the installed headers.
+
+.. option:: use_lit_shell=<bool>
+
+  Enable or disable the use of LIT's internal shell in ShTests. If the
+  environment variable LIT_USE_INTERNAL_SHELL is present then that is used as
+  the default value. Otherwise the default value is True on Windows and False
+  on every other platform.
+
+.. option:: no_default_flags=<bool>
+
+  **Default**: False
+
+  Disable all default compile and link flags from being added. When this
+  option is used only flags specified using the compile_flags and link_flags
+  will be used.
+
+.. option:: compile_flags="<list-of-args>"
+
+  Specify additional compile flags as a space delimited string.
+  Note: This options should not be used to change the standard version used.
+
+.. option:: link_flags="<list-of-args>"
+
+  Specify additional link flags as a space delimited string.
+
+.. option:: std=<standard version>
+
+  **Values**: c++98, c++03, c++11, c++14, c++1z
+
+  Change the standard version used when building the tests.
+
+.. option:: debug_level=<level>
+
+  **Values**: 0, 1
+
+  Enable the use of debug mode. Level 0 enables assertions and level 1 enables
+  assertions and debugging of iterator misuse.
+
+.. option:: use_sanitizer=<sanitizer name>
+
+  **Values**: Memory, MemoryWithOrigins, Address, Undefined
+
+  Run the tests using the given sanitizer. If LLVM_USE_SANITIZER was given when
+  building libc++ then that sanitizer will be used by default.
+
+.. option:: color_diagnostics
+
+  Enable the use of colorized compile diagnostics. If the color_diagnostics
+  option is specified or the environment variable LIBCXX_COLOR_DIAGNOSTICS is
+  present then color diagnostics will be enabled.
+
+
+Environment Variables
+---------------------
+
+.. envvar:: LIBCXX_SITE_CONFIG=<path/to/lit.site.cfg>
+
+  Specify the site configuration to use when running the tests.
+  Also see :option:`libcxx_site_config`.
+
+.. envvar:: LIBCXX_COLOR_DIAGNOSTICS
+
+  If ``LIBCXX_COLOR_DIAGNOSTICS`` is defined then the test suite will attempt
+  to use color diagnostic outputs from the compiler.
+  Also see :option:`color_diagnostics`.

docs/UsingLibcxx.rst

+============
+Using libc++
+============
+
+Getting Started
+===============
+
+If you already have libc++ installed you can use it with clang.
+
+.. code-block:: bash
+
+    $ clang++ -stdlib=libc++ test.cpp
+    $ clang++ -std=c++11 -stdlib=libc++ test.cpp
+
+On OS X and FreeBSD libc++ is the default standard library
+and the ``-stdlib=libc++`` is not required.
+
+.. _alternate libcxx:
+
+If you want to select an alternate installation of libc++ you
+can use the following options.
+
+.. code-block:: bash
+
+  $ clang++ -std=c++11 -stdlib=libc++ -nostdinc++ \
+            -I<libcxx-install-prefix>/include/c++/v1 \
+            -L<libcxx-install-prefix>/lib \
+            -Wl,-rpath,<libcxx-install-prefix>/lib \
+            test.cpp
+
+The option ``-Wl,-rpath,<libcxx-install-prefix>/lib`` adds a runtime library
+search path. Meaning that the systems dynamic linker will look for libc++ in
+``<libcxx-install-prefix>/lib`` whenever the program is run. Alternatively the
+environment variable ``LD_LIBRARY_PATH`` (``DYLD_LIBRARY_PATH`` on OS X) can
+be used to change the dynamic linkers search paths after a program is compiled.
+
+An example of using ``LD_LIBRARY_PATH``:
+
+.. code-block:: bash
+
+  $ clang++ -stdlib=libc++ -nostdinc++ \
+            -I<libcxx-install-prefix>/include/c++/v1
+            -L<libcxx-install-prefix>/lib \
+            test.cpp -o
+  $ ./a.out # Searches for libc++ in the systems library paths.
+  $ export LD_LIBRARY_PATH=<libcxx-install-prefix>/lib
+  $ ./a.out # Searches for libc++ along LD_LIBRARY_PATH
+
+
+
+Using libc++ on Linux
+=====================
+
+On Linux libc++ typically links to a shared version of libc++abi. Unfortunately
+you can't simply run clang with "-stdlib=libc++" as clang is not set up to
+link for this configuration. To get around this you'll have to manually
+link libc++abi yourself. For example:
+
+.. code-block:: bash
+
+  $ clang++ -stdlib=libc++ test.cpp -lc++ -lc++abi -lm -lc -lgcc_s -lgcc
+
+Alternately, you could just add libc++abi to your libraries list, which in
+most situations will give the same result:
+
+.. code-block:: bash
+
+  $ clang++ -stdlib=libc++ test.cpp -lc++abi
+
+
+Using libc++ with GCC
+---------------------
+
+GCC does not provide a way to switch from libstdc++ to libc++. You must manually
+configure the compile and link commands.
+
+In particular you must tell GCC to remove the libstdc++ include directories
+using ``-nostdinc++`` and to not link libstdc++.so using ``-nodefaultlibs``.
+
+Note that ``-nodefaultlibs`` removes all of the standard system libraries and
+not just libstdc++ so they must be manually linked. For example:
+
+.. code-block:: bash
+
+  $ g++ -nostdinc++ -I<libcxx-install-prefix>/include/c++/v1 \
+         test.cpp -nodefaultlibs -lc++ -lc++abi -lm -lc -lgcc_s -lgcc

docs/_static/llvm.css

+/*
+ * LLVM documentation style sheet
+ */
+
+/* Common styles */
+.body { color: black; background: white; margin: 0 0 0 0 }
+
+/* No borders on image links */
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+
+address img { float: right; width: 88px; height: 31px; }
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+
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+              text-align: center; vertical-align: middle; }
+/*
+ * Documentation
+ */
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+  padding-left: 8pt;
+  padding-top: 1px;
+  padding-bottom: 2px
+}
+
+h1, .doc_title, .title { text-align: left;   font-size: 25pt }
+
+h2, .doc_section   { text-align: center; font-size: 22pt;
+                     margin: 20pt 0pt 5pt 0pt; }
+
+h3, .doc_subsection { width: 75%;
+                      text-align: left;  font-size: 12pt;
+                      padding: 4pt 4pt 4pt 4pt;
+                      margin: 1.5em 0.5em 0.5em 0.5em }
+
+h4, .doc_subsubsection { margin: 2.0em 0.5em 0.5em 0.5em;
+                         font-weight: bold; font-style: oblique;
+                         border-bottom: 1px solid #999999; font-size: 12pt;
+                         width: 75%; }
+
+.doc_author     { text-align: left; font-weight: bold; padding-left: 20pt }
+.doc_text       { text-align: left; padding-left: 20pt; padding-right: 10pt }
+
+.doc_footer     { text-align: left; padding: 0 0 0 0 }
+
+.doc_hilite     { color: blue; font-weight: bold; }
+
+.doc_table      { text-align: center; width: 90%;
+                  padding: 1px 1px 1px 1px; border: 1px; }
+
+.doc_warning    { color: red; font-weight: bold }
+
+/* <div class="doc_code"> would use this class, and <div> adds more padding */
+.doc_code, .literal-block
+                { border: solid 1px gray; background: #eeeeee;
+                  margin: 0 1em 0 1em;
+                  padding: 0 1em 0 1em;
+                  display: table;
+                }
+
+blockquote pre {
+        padding: 1em 2em 1em 1em;
+        border: solid 1px gray;
+        background: #eeeeee;
+        margin: 0 1em 0 1em;
+        display: table;
+}
+
+h2+div, h2+p {text-align: left; padding-left: 20pt; padding-right: 10pt;}
+h3+div, h3+p {text-align: left; padding-left: 20pt; padding-right: 10pt;}
+h4+div, h4+p {text-align: left; padding-left: 20pt; padding-right: 10pt;}
+
+/* It is preferrable to use <pre class="doc_code"> everywhere instead of the
+ * <div class="doc_code"><pre>...</ptr></div> construct.
+ *
+ * Once all docs use <pre> for code regions, this style can  be merged with the
+ * one above, and we can drop the [pre] qualifier.
+ */
+pre.doc_code, .literal-block { padding: 1em 2em 1em 1em }
+
+.doc_notes      { background: #fafafa; border: 1px solid #cecece;
+                  display: table; padding: 0 1em 0 .1em }
+
+table.layout    { text-align: left; border: none; border-collapse: collapse;
+                  padding: 4px 4px 4px 4px; }
+tr.layout, td.layout, td.left, td.right
+                { border: none; padding: 4pt 4pt 2pt 2pt; vertical-align: top; }
+td.left         { text-align: left }
+td.right        { text-align: right }
+th.layout       { border: none; font-weight: bold; font-size: 105%;
+                  text-align: center; vertical-align: middle; }
+
+/* Left align table cell */
+.td_left        { border: 2px solid gray; text-align: left; }
+
+/* ReST-specific */
+.title { margin-top: 0 }
+.topic-title{ display: none }
+div.contents ul { list-style-type: decimal }
+.toc-backref    { color: black; text-decoration: none; }

docs/_templates/indexsidebar.html

+<h3>Bugs</h3>
+
+<p>libc++ bugs should be reported at the
+  LLVM <a href="http://llvm.org/bugs">Bugzilla</a>.</p>
+
+<h3>Buildbots</h3>
+
+<p>libc++ buildbots can be found here</p>
+<ul>
+  <li><a href="http://lab.llvm.org:8011/console">LLVM Labs Builders</a></li>
+  <li><a href="http://lab.llvm.org:8080/green/view/Libcxx/">Apple Builders</a></li>
+</ul>
 No newline at end of file

docs/_templates/layout.html

+{% extends "!layout.html" %}
+
+{% block extrahead %}
+<style type="text/css">
+  table.right { float: right; margin-left: 20px; }
+  table.right td { border: 1px solid #ccc; }
+</style>
+{% endblock %}
+
+{% block rootrellink %}
+  <li><a href="{{ pathto('index') }}">libc++ Home</a>&nbsp;|&nbsp;</li>
+{% endblock %}

docs/_themes/llvm-theme/layout.html

+{#
+    sphinxdoc/layout.html
+    ~~~~~~~~~~~~~~~~~~~~~
+
+    Sphinx layout template for the sphinxdoc theme.
+
+    :copyright: Copyright 2007-2010 by the Sphinx team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+#}
+{% extends "basic/layout.html" %}
+
+{% block relbar1 %}
+<div class="logo">
+  <a href="{{ pathto('index') }}">
+    <img src="{{pathto("_static/logo.png", 1) }}"
+         alt="LLVM Logo" width="250" height="88"/></a>
+</div>
+{{ super() }}
+{% endblock %}
+
+{# put the sidebar before the body #}
+{% block sidebar1 %}{{ sidebar() }}{% endblock %}
+{% block sidebar2 %}{% endblock %}

docs/_themes/llvm-theme/static/llvm-theme.css

+/*
+ * sphinxdoc.css_t
+ * ~~~~~~~~~~~~~~~
+ *
+ * Sphinx stylesheet -- sphinxdoc theme.  Originally created by
+ * Armin Ronacher for Werkzeug.
+ *
+ * :copyright: Copyright 2007-2010 by the Sphinx team, see AUTHORS.
+ * :license: BSD, see LICENSE for details.
+ *
+ */
+
+@import url("basic.css");
+
+/* -- page layout ----------------------------------------------------------- */
+
+body {
+    font-family: 'Lucida Grande', 'Lucida Sans Unicode', 'Geneva',
+                 'Verdana', sans-serif;
+    font-size: 14px;
+    line-height: 150%;
+    text-align: center;
+    background-color: #BFD1D4;
+    color: black;
+    padding: 0;
+    border: 1px solid #aaa;
+
+    margin: 0px 80px 0px 80px;
+    min-width: 740px;
+}
+
+div.logo {
+    background-color: white;
+    text-align: left;
+    padding: 10px 10px 15px 15px;
+}
+
+div.document {
+    background-color: white;
+    text-align: left;
+    background-image: url(contents.png);
+    background-repeat: repeat-x;
+}
+
+div.bodywrapper {
+    margin: 0 240px 0 0;
+    border-right: 1px solid #ccc;
+}
+
+div.body {
+    margin: 0;
+    padding: 0.5em 20px 20px 20px;
+}
+
+div.related {
+    font-size: 1em;
+}
+
+div.related ul {
+    background-image: url(navigation.png);
+    height: 2em;
+    border-top: 1px solid #ddd;
+    border-bottom: 1px solid #ddd;
+}
+
+div.related ul li {
+    margin: 0;
+    padding: 0;
+    height: 2em;
+    float: left;
+}
+
+div.related ul li.right {
+    float: right;
+    margin-right: 5px;
+}
+
+div.related ul li a {
+    margin: 0;
+    padding: 0 5px 0 5px;
+    line-height: 1.75em;
+    color: #EE9816;
+}
+
+div.related ul li a:hover {
+    color: #3CA8E7;
+}
+
+div.sphinxsidebarwrapper {
+    padding: 0;
+}
+
+div.sphinxsidebar {
+    margin: 0;
+    padding: 0.5em 15px 15px 0;
+    width: 210px;
+    float: right;
+    font-size: 1em;
+    text-align: left;
+}
+
+div.sphinxsidebar h3, div.sphinxsidebar h4 {
+    margin: 1em 0 0.5em 0;
+    font-size: 1em;
+    padding: 0.1em 0 0.1em 0.5em;
+    color: white;
+    border: 1px solid #86989B;
+    background-color: #AFC1C4;
+}
+
+div.sphinxsidebar h3 a {
+    color: white;
+}
+
+div.sphinxsidebar ul {
+    padding-left: 1.5em;
+    margin-top: 7px;
+    padding: 0;
+    line-height: 130%;
+}
+
+div.sphinxsidebar ul ul {
+    margin-left: 20px;
+}
+
+div.footer {
+    background-color: #E3EFF1;
+    color: #86989B;
+    padding: 3px 8px 3px 0;
+    clear: both;
+    font-size: 0.8em;
+    text-align: right;
+}
+
+div.footer a {
+    color: #86989B;
+    text-decoration: underline;
+}
+
+/* -- body styles ----------------------------------------------------------- */
+
+p {
+    margin: 0.8em 0 0.5em 0;
+}
+
+a {
+    color: #CA7900;
+    text-decoration: none;
+}
+
+a:hover {
+    color: #2491CF;
+}
+
+div.body p a{
+    text-decoration: underline;
+}
+
+h1 {
+    margin: 0;
+    padding: 0.7em 0 0.3em 0;
+    font-size: 1.5em;
+    color: #11557C;
+}
+
+h2 {
+    margin: 1.3em 0 0.2em 0;
+    font-size: 1.35em;
+    padding: 0;
+}
+
+h3 {
+    margin: 1em 0 -0.3em 0;
+    font-size: 1.2em;
+}
+
+h3 a:hover {
+    text-decoration: underline;
+}
+
+div.body h1 a, div.body h2 a, div.body h3 a, div.body h4 a, div.body h5 a, div.body h6 a {
+    color: black!important;
+}
+
+div.body h1,
+div.body h2,
+div.body h3,
+div.body h4,
+div.body h5,
+div.body h6 {
+    background-color: #f2f2f2;
+    font-weight: normal;
+    color: #20435c;
+    border-bottom: 1px solid #ccc;
+    margin: 20px -20px 10px -20px;
+    padding: 3px 0 3px 10px;
+}
+
+div.body h1 { margin-top: 0; font-size: 200%; }
+div.body h2 { font-size: 160%; }
+div.body h3 { font-size: 140%; }
+div.body h4 { font-size: 120%; }
+div.body h5 { font-size: 110%; }
+div.body h6 { font-size: 100%; }
+
+h1 a.anchor, h2 a.anchor, h3 a.anchor, h4 a.anchor, h5 a.anchor, h6 a.anchor {
+    display: none;
+    margin: 0 0 0 0.3em;
+    padding: 0 0.2em 0 0.2em;
+    color: #aaa!important;
+}
+
+h1:hover a.anchor, h2:hover a.anchor, h3:hover a.anchor, h4:hover a.anchor,
+h5:hover a.anchor, h6:hover a.anchor {
+    display: inline;
+}
+
+h1 a.anchor:hover, h2 a.anchor:hover, h3 a.anchor:hover, h4 a.anchor:hover,
+h5 a.anchor:hover, h6 a.anchor:hover {
+    color: #777;
+    background-color: #eee;
+}
+
+a.headerlink {
+    color: #c60f0f!important;
+    font-size: 1em;
+    margin-left: 6px;
+    padding: 0 4px 0 4px;
+    text-decoration: none!important;
+}
+
+a.headerlink:hover {
+    background-color: #ccc;
+    color: white!important;
+}
+
+cite, code, tt {
+    font-family: 'Consolas', 'Deja Vu Sans Mono',
+                 'Bitstream Vera Sans Mono', monospace;
+    font-size: 0.95em;
+}
+
+:not(a.reference) > tt {
+    background-color: #f2f2f2;
+    border-bottom: 1px solid #ddd;
+    color: #333;
+}
+
+tt.descname, tt.descclassname, tt.xref {
+    border: 0;
+}
+
+hr {
+    border: 1px solid #abc;
+    margin: 2em;
+}
+
+p a tt {
+    border: 0;
+    color: #CA7900;
+}
+
+p a tt:hover {
+    color: #2491CF;
+}
+
+a tt {
+    border: none;
+}
+
+pre {
+    font-family: 'Consolas', 'Deja Vu Sans Mono',
+                 'Bitstream Vera Sans Mono', monospace;
+    font-size: 0.95em;
+    line-height: 120%;
+    padding: 0.5em;
+    border: 1px solid #ccc;
+    background-color: #f8f8f8;
+}
+
+pre a {
+    color: inherit;
+    text-decoration: underline;
+}
+
+td.linenos pre {
+    padding: 0.5em 0;
+}
+
+div.quotebar {
+    background-color: #f8f8f8;
+    max-width: 250px;
+    float: right;
+    padding: 2px 7px;
+    border: 1px solid #ccc;
+}
+
+div.topic {
+    background-color: #f8f8f8;
+}
+
+table {
+    border-collapse: collapse;
+    margin: 0 -0.5em 0 -0.5em;
+}
+
+table td, table th {
+    padding: 0.2em 0.5em 0.2em 0.5em;
+}
+
+div.admonition, div.warning {
+    font-size: 0.9em;
+    margin: 1em 0 1em 0;
+    border: 1px solid #86989B;
+    background-color: #f7f7f7;
+    padding: 0;
+}
+
+div.admonition p, div.warning p {
+    margin: 0.5em 1em 0.5em 1em;
+    padding: 0;
+}
+
+div.admonition pre, div.warning pre {
+    margin: 0.4em 1em 0.4em 1em;
+}
+
+div.admonition p.admonition-title,
+div.warning p.admonition-title {
+    margin: 0;
+    padding: 0.1em 0 0.1em 0.5em;
+    color: white;
+    border-bottom: 1px solid #86989B;
+    font-weight: bold;
+    background-color: #AFC1C4;
+}
+
+div.warning {
+    border: 1px solid #940000;
+}
+
+div.warning p.admonition-title {
+    background-color: #CF0000;
+    border-bottom-color: #940000;
+}
+
+div.admonition ul, div.admonition ol,
+div.warning ul, div.warning ol {
+    margin: 0.1em 0.5em 0.5em 3em;
+    padding: 0;
+}
+
+div.versioninfo {
+    margin: 1em 0 0 0;
+    border: 1px solid #ccc;
+    background-color: #DDEAF0;
+    padding: 8px;
+    line-height: 1.3em;
+    font-size: 0.9em;
+}
+
+.viewcode-back {
+    font-family: 'Lucida Grande', 'Lucida Sans Unicode', 'Geneva',
+                 'Verdana', sans-serif;
+}
+
+div.viewcode-block:target {
+    background-color: #f4debf;
+    border-top: 1px solid #ac9;
+    border-bottom: 1px solid #ac9;
+}

docs/_themes/llvm-theme/theme.conf

+[theme]
+inherit = basic
+stylesheet = llvm-theme.css
+pygments_style = friendly

docs/conf.py

+# -*- coding: utf-8 -*-
+#
+# libc++ documentation build configuration file.
+#
+# This file is execfile()d with the current directory set to its containing dir.
+#
+# Note that not all possible configuration values are present in this
+# autogenerated file.
+#
+# All configuration values have a default; values that are commented out
+# serve to show the default.
+
+import sys, os
+
+# If extensions (or modules to document with autodoc) are in another directory,
+# add these directories to sys.path here. If the directory is relative to the
+# documentation root, use os.path.abspath to make it absolute, like shown here.
+#sys.path.insert(0, os.path.abspath('.'))
+
+# -- General configuration -----------------------------------------------------
+
+# If your documentation needs a minimal Sphinx version, state it here.
+#needs_sphinx = '1.0'
+
+# Add any Sphinx extension module names here, as strings. They can be extensions
+# coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
+extensions = ['sphinx.ext.intersphinx', 'sphinx.ext.todo']
+
+# Add any paths that contain templates here, relative to this directory.
+templates_path = ['_templates']
+
+# The suffix of source filenames.
+source_suffix = '.rst'
+
+# The encoding of source files.
+#source_encoding = 'utf-8-sig'
+
+# The master toctree document.
+master_doc = 'index'
+
+# General information about the project.
+project = u'libc++'
+copyright = u'2011-2015, LLVM Project'
+
+# The version info for the project you're documenting, acts as replacement for
+# |version| and |release|, also used in various other places throughout the
+# built documents.
+#
+# The short X.Y version.
+version = '3.7'
+# The full version, including alpha/beta/rc tags.
+release = '3.7'
+
+# The language for content autogenerated by Sphinx. Refer to documentation
+# for a list of supported languages.
+#language = None
+
+# There are two options for replacing |today|: either, you set today to some
+# non-false value, then it is used:
+#today = ''
+# Else, today_fmt is used as the format for a strftime call.
+today_fmt = '%Y-%m-%d'
+
+# List of patterns, relative to source directory, that match files and
+# directories to ignore when looking for source files.
+exclude_patterns = ['_build']
+
+# The reST default role (used for this markup: `text`) to use for all documents.
+#default_role = None
+
+# If true, '()' will be appended to :func: etc. cross-reference text.
+#add_function_parentheses = True
+
+# If true, the current module name will be prepended to all description
+# unit titles (such as .. function::).
+#add_module_names = True
+
+# If true, sectionauthor and moduleauthor directives will be shown in the
+# output. They are ignored by default.
+show_authors = True
+
+# The name of the Pygments (syntax highlighting) style to use.
+pygments_style = 'friendly'
+
+# A list of ignored prefixes for module index sorting.
+#modindex_common_prefix = []
+
+
+# -- Options for HTML output ---------------------------------------------------
+
+# The theme to use for HTML and HTML Help pages.  See the documentation for
+# a list of builtin themes.
+html_theme = 'llvm-theme'
+#html_theme = 'haiku'
+# Theme options are theme-specific and customize the look and feel of a theme
+# further.  For a list of options available for each theme, see the
+# documentation.
+html_theme_options = {}
+#html_theme_options = { "nosidebar": True }
+
+# Add any paths that contain custom themes here, relative to this directory.
+html_theme_path = ["_themes"]
+
+# The name for this set of Sphinx documents.  If None, it defaults to
+# "<project> v<release> documentation".
+#html_title = None
+
+# A shorter title for the navigation bar.  Default is the same as html_title.
+#html_short_title = None
+
+# The name of an image file (relative to this directory) to place at the top
+# of the sidebar.
+#html_logo = None
+
+# If given, this must be the name of an image file (path relative to the
+# configuration directory) that is the favicon of the docs. Modern browsers use
+# this as icon for tabs, windows and bookmarks. It should be a Windows-style
+# icon file (.ico), which is 16x16 or 32x32 pixels large. Default: None.  The
+# image file will be copied to the _static directory of the output HTML, but
+# only if the file does not already exist there.
+html_favicon = '_static/favicon.ico'
+
+# Add any paths that contain custom static files (such as style sheets) here,
+# relative to this directory. They are copied after the builtin static files,
+# so a file named "default.css" will overwrite the builtin "default.css".
+html_static_path = ['_static']
+
+# If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
+# using the given strftime format.
+html_last_updated_fmt = '%Y-%m-%d'
+
+# If true, SmartyPants will be used to convert quotes and dashes to
+# typographically correct entities.
+#html_use_smartypants = True
+
+# Custom sidebar templates, maps document names to template names.
+#html_sidebars = {'index': 'indexsidebar.html'}
+
+# Additional templates that should be rendered to pages, maps page names to
+# template names.
+# html_additional_pages = {'index': 'index.html'}
+
+# If false, no module index is generated.
+#html_domain_indices = True
+
+# If false, no index is generated.
+#html_use_index = True
+
+# If true, the index is split into individual pages for each letter.
+#html_split_index = False
+
+# If true, links to the reST sources are added to the pages.
+html_show_sourcelink = True
+
+# If true, "Created using Sphinx" is shown in the HTML footer. Default is True.
+#html_show_sphinx = True
+
+# If true, "(C) Copyright ..." is shown in the HTML footer. Default is True.
+#html_show_copyright = True
+
+# If true, an OpenSearch description file will be output, and all pages will
+# contain a <link> tag referring to it.  The value of this option must be the
+# base URL from which the finished HTML is served.
+#html_use_opensearch = ''
+
+# This is the file name suffix for HTML files (e.g. ".xhtml").
+#html_file_suffix = None
+
+# Output file base name for HTML help builder.
+htmlhelp_basename = 'libcxxdoc'
+
+
+# -- Options for LaTeX output --------------------------------------------------
+
+latex_elements = {
+# The paper size ('letterpaper' or 'a4paper').
+#'papersize': 'letterpaper',
+
+# The font size ('10pt', '11pt' or '12pt').
+#'pointsize': '10pt',
+
+# Additional stuff for the LaTeX preamble.
+#'preamble': '',
+}
+
+# Grouping the document tree into LaTeX files. List of tuples
+# (source start file, target name, title, author, documentclass [howto/manual]).
+latex_documents = [
+  ('contents', 'libcxx.tex', u'libcxx Documentation',
+   u'LLVM project', 'manual'),
+]
+
+# The name of an image file (relative to this directory) to place at the top of
+# the title page.
+#latex_logo = None
+
+# For "manual" documents, if this is true, then toplevel headings are parts,
+# not chapters.
+#latex_use_parts = False
+
+# If true, show page references after internal links.
+#latex_show_pagerefs = False
+
+# If true, show URL addresses after external links.
+#latex_show_urls = False
+
+# Documents to append as an appendix to all manuals.
+#latex_appendices = []
+
+# If false, no module index is generated.
+#latex_domain_indices = True
+
+
+# -- Options for manual page output --------------------------------------------
+
+# One entry per manual page. List of tuples
+# (source start file, name, description, authors, manual section).
+man_pages = [
+    ('contents', 'libc++', u'libc++ Documentation',
+     [u'LLVM project'], 1)
+]
+
+# If true, show URL addresses after external links.
+#man_show_urls = False
+
+
+# -- Options for Texinfo output ------------------------------------------------
+
+# Grouping the document tree into Texinfo files. List of tuples
+# (source start file, target name, title, author,
+#  dir menu entry, description, category)
+texinfo_documents = [
+  ('contents', 'libc++', u'libc++ Documentation',
+   u'LLVM project', 'libc++', 'One line description of project.',
+   'Miscellaneous'),
+]
+
+# Documents to append as an appendix to all manuals.
+#texinfo_appendices = []
+
+# If false, no module index is generated.
+#texinfo_domain_indices = True
+
+# How to display URL addresses: 'footnote', 'no', or 'inline'.
+#texinfo_show_urls = 'footnote'
+
+
+# FIXME: Define intersphinx configration.
+intersphinx_mapping = {}
+
+
+# -- Options for extensions ----------------------------------------------------
+
+# Enable this if you want TODOs to show up in the generated documentation.
+todo_include_todos = True

docs/index.rst

+.. _index:
+
+=============================
+"libc++" C++ Standard Library
+=============================
+
+Overview
+========
+
+libc++ is a new implementation of the C++ standard library, targeting C++11.
+
+* Features and Goals
+
+  * Correctness as defined by the C++11 standard.
+  * Fast execution.
+  * Minimal memory use.
+  * Fast compile times.
+  * ABI compatibility with gcc's libstdc++ for some low-level features
+    such as exception objects, rtti and memory allocation.
+  * Extensive unit tests.
+
+* Design and Implementation:
+
+  * Extensive unit tests
+  * Internal linker model can be dumped/read to textual format
+  * Additional linking features can be plugged in as "passes"
+  * OS specific and CPU specific code factored out
+
+
+Getting Started with libc++
+---------------------------
+
+.. toctree::
+   :maxdepth: 2
+
+   UsingLibcxx
+   BuildingLibcxx
+   TestingLibcxx
+
+Current Status
+--------------
+
+After its initial introduction, many people have asked "why start a new
+library instead of contributing to an existing library?" (like Apache's
+libstdcxx, GNU's libstdc++, STLport, etc).  There are many contributing
+reasons, but some of the major ones are:
+
+From years of experience (including having implemented the standard
+library before), we've learned many things about implementing
+the standard containers which require ABI breakage and fundamental changes
+to how they are implemented.  For example, it is generally accepted that
+building std::string using the "short string optimization" instead of
+using Copy On Write (COW) is a superior approach for multicore
+machines (particularly in C++11, which has rvalue references).  Breaking
+ABI compatibility with old versions of the library was
+determined to be critical to achieving the performance goals of
+libc++.
+
+Mainline libstdc++ has switched to GPL3, a license which the developers
+of libc++ cannot use.  libstdc++ 4.2 (the last GPL2 version) could be
+independently extended to support C++11, but this would be a fork of the
+codebase (which is often seen as worse for a project than starting a new
+independent one).  Another problem with libstdc++ is that it is tightly
+integrated with G++ development, tending to be tied fairly closely to the
+matching version of G++.
+
+STLport and the Apache libstdcxx library are two other popular
+candidates, but both lack C++11 support.  Our experience (and the
+experience of libstdc++ developers) is that adding support for C++11 (in
+particular rvalue references and move-only types) requires changes to
+almost every class and function, essentially amounting to a rewrite.
+Faced with a rewrite, we decided to start from scratch and evaluate every
+design decision from first principles based on experience.
+
+Further, both projects are apparently abandoned: STLport 5.2.1 was
+released in Oct'08, and STDCXX 4.2.1 in May'08.
+
+Platform and Compiler Support
+-----------------------------
+
+libc++ is known to work on the following platforms, using gcc-4.2 and
+clang  (lack of C++11 language support disables some functionality).
+Note that functionality provided by ``<atomic>`` is only functional with clang
+and GCC.
+
+============ ==================== ============ ========================
+OS           Arch                 Compilers    ABI Library
+============ ==================== ============ ========================
+Mac OS X     i386, x86_64         Clang, GCC   libc++abi
+FreeBSD 10+  i386, x86_64, ARM    Clang, GCC   libcxxrt, libc++abi
+Linux        i386, x86_64         Clang, GCC   libc++abi
+============ ==================== ============ ========================
+
+The following minimum compiler versions are strongly recommended.
+
+* Clang 3.5 and above
+* GCC 4.7 and above.
+
+Anything older *may* work.
+
+C++ Dialect Support
+---------------------
+
+* C++11 - Complete
+* `C++14 - Complete <cxx14 status_>`__
+* `C++1z - In Progress <cxx1z status_>`__
+* `Post C++14 Technical Specifications - In Progress <ts status_>`__
+
+.. _cxx14 status: http://libcxx.llvm.org/cxx1y_status.html
+.. _cxx1z status: http://libcxx.llvm.org/cxx1z_status.html
+.. _ts status: http://libcxx.llvm.org/ts1z_status.html
+
+
+Notes and Known Issues
+----------------------
+
+This list contains known issues with libc++
+
+* Building libc++ with ``-fno-rtti`` is not supported. However
+  linking against it with ``-fno-rtti`` is supported.
+* On OS X v10.8 and older the CMake option ``-DLIBCXX_LIBCPPABI_VERSION=""``
+  must be used during configuration.
+
+
+A full list of currently open libc++ bugs can be `found here <libcxx bug list_>`__.
+
+.. _libcxx bug list: https://llvm.org/bugs/buglist.cgi?component=All%20Bugs&product=libc%2B%2B&query_format=advanced&resolution=---&order=changeddate%20DESC%2Cassigned_to%20DESC%2Cbug_status%2Cpriority%2Cbug_id&list_id=74184
+
+Design Documents
+----------------
+
+* `<atomic> design <http://libcxx.llvm.org/atomic_design.html>`_
+* `<type_traits> design <http://libcxx.llvm.org/type_traits_design.html>`_
+* `Status of debug mode <http://libcxx.llvm.org/debug_mode.html>`_
+* `Notes by Marshall Clow <clow notes_>`__
+
+.. _clow notes: https://cplusplusmusings.wordpress.com/2012/07/05/clang-and-standard-libraries-on-mac-os-x/
+
+Getting Involved
+================
+
+First please review our `Developer's Policy <http://llvm.org/docs/DeveloperPolicy.html>`__.
+
+**Bug Reports**
+
+If you think you've found a bug in libc++, please report it using
+the _`LLVM Bugzilla`. If you're not sure, you
+can post a message to the `cfe-dev`_.  mailing list or on IRC.
+Please include "libc++" in your subject.
+
+**Patches**
+
+If you want to contribute a patch to libc++, the best place for that is
+`Phabricator <phab doc_>`__. Please include [libcxx] in the subject and
+add `cfe-commits` as a subscriber.
+
+**Discussion and Questions**
+
+Send discussions and questions to the `clang mailing list <cfe-dev_>`__.
+Please include [libcxx] in the subject.
+
+.. _phab doc: http://llvm.org/docs/Phabricator.html
+.. _cfe-dev: http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev
+
+Links
+=====
+
+* `Getting started with LLVM <http://llvm.org/docs/GettingStarted.html>`_
+* `libc++abi Homepage <libc++abi_>`__
+
+.. _`libc++abi`: http://libcxxabi.llvm.org/