Eric Fiselier | b9f425a | 2015-08-22 19:40:49 +0000 | [diff] [blame] | 1 | |
| 2 | =============== |
| 3 | Building libc++ |
| 4 | =============== |
| 5 | |
| 6 | .. contents:: |
| 7 | :local: |
| 8 | |
Eric Fiselier | 7039fa1 | 2016-05-03 22:32:08 +0000 | [diff] [blame] | 9 | .. _build instructions: |
| 10 | |
Eric Fiselier | b9f425a | 2015-08-22 19:40:49 +0000 | [diff] [blame] | 11 | Getting Started |
| 12 | =============== |
| 13 | |
| 14 | On Mac OS 10.7 (Lion) and later, the easiest way to get this library is to install |
| 15 | Xcode 4.2 or later. However if you want to install tip-of-trunk from here |
| 16 | (getting the bleeding edge), read on. |
| 17 | |
| 18 | The basic steps needed to build libc++ are: |
| 19 | |
| 20 | #. Checkout LLVM: |
| 21 | |
| 22 | * ``cd where-you-want-llvm-to-live`` |
| 23 | * ``svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm`` |
| 24 | |
| 25 | #. Checkout libc++: |
| 26 | |
| 27 | * ``cd where-you-want-llvm-to-live`` |
Eric Fiselier | 8459d20 | 2015-12-14 22:26:28 +0000 | [diff] [blame] | 28 | * ``cd llvm/projects`` |
Eric Fiselier | b9f425a | 2015-08-22 19:40:49 +0000 | [diff] [blame] | 29 | * ``svn co http://llvm.org/svn/llvm-project/libcxx/trunk libcxx`` |
| 30 | |
| 31 | #. Checkout libc++abi: |
| 32 | |
| 33 | * ``cd where-you-want-llvm-to-live`` |
| 34 | * ``cd llvm/projects`` |
Eric Fiselier | 8459d20 | 2015-12-14 22:26:28 +0000 | [diff] [blame] | 35 | * ``svn co http://llvm.org/svn/llvm-project/libcxxabi/trunk libcxxabi`` |
Eric Fiselier | b9f425a | 2015-08-22 19:40:49 +0000 | [diff] [blame] | 36 | |
| 37 | #. Configure and build libc++ with libc++abi: |
| 38 | |
Alexey Samsonov | d118e32 | 2016-01-30 01:11:42 +0000 | [diff] [blame] | 39 | CMake is the only supported configuration system. |
Eric Fiselier | b9f425a | 2015-08-22 19:40:49 +0000 | [diff] [blame] | 40 | |
| 41 | Clang is the preferred compiler when building and using libc++. |
| 42 | |
| 43 | * ``cd where you want to build llvm`` |
| 44 | * ``mkdir build`` |
| 45 | * ``cd build`` |
| 46 | * ``cmake -G <generator> [options] <path to llvm sources>`` |
| 47 | |
| 48 | For more information about configuring libc++ see :ref:`CMake Options`. |
| 49 | |
| 50 | * ``make cxx`` --- will build libc++ and libc++abi. |
| 51 | * ``make check-libcxx check-libcxxabi`` --- will run the test suites. |
| 52 | |
| 53 | Shared libraries for libc++ and libc++ abi should now be present in llvm/build/lib. |
| 54 | See :ref:`using an alternate libc++ installation <alternate libcxx>` |
| 55 | |
| 56 | #. **Optional**: Install libc++ and libc++abi |
| 57 | |
| 58 | If your system already provides a libc++ installation it is important to be |
| 59 | careful not to replace it. Remember Use the CMake option ``CMAKE_INSTALL_PREFIX`` to |
| 60 | select a safe place to install libc++. |
| 61 | |
| 62 | * ``make install-libcxx install-libcxxabi`` --- Will install the libraries and the headers |
| 63 | |
| 64 | .. warning:: |
| 65 | * Replacing your systems libc++ installation could render the system non-functional. |
| 66 | * Mac OS X will not boot without a valid copy of ``libc++.1.dylib`` in ``/usr/lib``. |
| 67 | |
| 68 | |
| 69 | The instructions are for building libc++ on |
| 70 | FreeBSD, Linux, or Mac using `libc++abi`_ as the C++ ABI library. |
| 71 | On Linux, it is also possible to use :ref:`libsupc++ <libsupcxx>` or libcxxrt. |
| 72 | |
Eric Fiselier | b22481a | 2015-09-06 23:31:16 +0000 | [diff] [blame] | 73 | It is sometimes beneficial to build outside of the LLVM tree. An out-of-tree |
| 74 | build would look like this: |
Eric Fiselier | b9f425a | 2015-08-22 19:40:49 +0000 | [diff] [blame] | 75 | |
| 76 | .. code-block:: bash |
| 77 | |
| 78 | $ cd where-you-want-libcxx-to-live |
| 79 | $ # Check out llvm, libc++ and libc++abi. |
| 80 | $ ``svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm`` |
| 81 | $ ``svn co http://llvm.org/svn/llvm-project/libcxx/trunk libcxx`` |
| 82 | $ ``svn co http://llvm.org/svn/llvm-project/libcxxabi/trunk libcxxabi`` |
| 83 | $ cd where-you-want-to-build |
| 84 | $ mkdir build && cd build |
| 85 | $ export CC=clang CXX=clang++ |
| 86 | $ cmake -DLLVM_PATH=path/to/llvm \ |
| 87 | -DLIBCXX_CXX_ABI=libcxxabi \ |
| 88 | -DLIBCXX_CXX_ABI_INCLUDE_PATHS=path/to/libcxxabi/include \ |
| 89 | path/to/libcxx |
| 90 | $ make |
| 91 | $ make check-libcxx # optional |
| 92 | |
| 93 | |
| 94 | .. _`libc++abi`: http://libcxxabi.llvm.org/ |
| 95 | |
| 96 | |
| 97 | .. _CMake Options: |
| 98 | |
| 99 | CMake Options |
| 100 | ============= |
| 101 | |
| 102 | Here are some of the CMake variables that are used often, along with a |
| 103 | brief explanation and LLVM-specific notes. For full documentation, check the |
| 104 | CMake docs or execute ``cmake --help-variable VARIABLE_NAME``. |
| 105 | |
| 106 | **CMAKE_BUILD_TYPE**:STRING |
| 107 | Sets the build type for ``make`` based generators. Possible values are |
| 108 | Release, Debug, RelWithDebInfo and MinSizeRel. On systems like Visual Studio |
| 109 | the user sets the build type with the IDE settings. |
| 110 | |
| 111 | **CMAKE_INSTALL_PREFIX**:PATH |
| 112 | Path where LLVM will be installed if "make install" is invoked or the |
| 113 | "INSTALL" target is built. |
| 114 | |
| 115 | **CMAKE_CXX_COMPILER**:STRING |
| 116 | The C++ compiler to use when building and testing libc++. |
| 117 | |
| 118 | |
| 119 | .. _libcxx-specific options: |
| 120 | |
| 121 | libc++ specific options |
| 122 | ----------------------- |
| 123 | |
Eric Fiselier | 7039fa1 | 2016-05-03 22:32:08 +0000 | [diff] [blame] | 124 | .. option:: LIBCXX_INSTALL_LIBRARY:BOOL |
| 125 | |
| 126 | **Default**: ``ON`` |
| 127 | |
| 128 | Toggle the installation of the library portion of libc++. |
| 129 | |
| 130 | .. option:: LIBCXX_INSTALL_HEADERS:BOOL |
| 131 | |
| 132 | **Default**: ``ON`` |
| 133 | |
| 134 | Toggle the installation of the libc++ headers. |
| 135 | |
Eric Fiselier | b9f425a | 2015-08-22 19:40:49 +0000 | [diff] [blame] | 136 | .. option:: LIBCXX_ENABLE_ASSERTIONS:BOOL |
| 137 | |
| 138 | **Default**: ``ON`` |
| 139 | |
| 140 | Build libc++ with assertions enabled. |
| 141 | |
| 142 | .. option:: LIBCXX_BUILD_32_BITS:BOOL |
| 143 | |
| 144 | **Default**: ``OFF`` |
| 145 | |
| 146 | Build libc++ as a 32 bit library. Also see :option:`LLVM_BUILD_32_BITS`. |
| 147 | |
| 148 | .. option:: LIBCXX_ENABLE_SHARED:BOOL |
| 149 | |
| 150 | **Default**: ``ON`` |
| 151 | |
| 152 | Build libc++ as a shared library. If ``OFF`` is specified then libc++ is |
| 153 | built as a static library. |
| 154 | |
| 155 | .. option:: LIBCXX_LIBDIR_SUFFIX:STRING |
| 156 | |
| 157 | Extra suffix to append to the directory where libraries are to be installed. |
| 158 | This option overrides :option:`LLVM_LIBDIR_SUFFIX`. |
| 159 | |
Eric Fiselier | 7039fa1 | 2016-05-03 22:32:08 +0000 | [diff] [blame] | 160 | |
| 161 | .. _libc++experimental options: |
| 162 | |
| 163 | libc++experimental Specific Options |
| 164 | ------------------------------------ |
| 165 | |
| 166 | .. option:: LIBCXX_ENABLE_EXPERIMENTAL_LIBRARY:BOOL |
| 167 | |
| 168 | **Default**: ``ON`` |
| 169 | |
| 170 | Build and test libc++experimental.a. |
| 171 | |
| 172 | .. option:: LIBCXX_INSTALL_EXPERIMENTAL_LIBRARY:BOOL |
| 173 | |
| 174 | **Default**: ``OFF`` |
| 175 | |
| 176 | Install libc++experimental.a alongside libc++. |
| 177 | |
| 178 | |
Eric Fiselier | b9f425a | 2015-08-22 19:40:49 +0000 | [diff] [blame] | 179 | .. _ABI Library Specific Options: |
| 180 | |
| 181 | ABI Library Specific Options |
| 182 | ---------------------------- |
| 183 | |
| 184 | .. option:: LIBCXX_CXX_ABI:STRING |
| 185 | |
| 186 | **Values**: ``none``, ``libcxxabi``, ``libcxxrt``, ``libstdc++``, ``libsupc++``. |
| 187 | |
| 188 | Select the ABI library to build libc++ against. |
| 189 | |
| 190 | .. option:: LIBCXX_CXX_ABI_INCLUDE_PATHS:PATHS |
| 191 | |
| 192 | Provide additional search paths for the ABI library headers. |
| 193 | |
| 194 | .. option:: LIBCXX_CXX_ABI_LIBRARY_PATH:PATH |
| 195 | |
| 196 | Provide the path to the ABI library that libc++ should link against. |
| 197 | |
| 198 | .. option:: LIBCXX_ENABLE_STATIC_ABI_LIBRARY:BOOL |
| 199 | |
| 200 | **Default**: ``OFF`` |
| 201 | |
| 202 | If this option is enabled, libc++ will try and link the selected ABI library |
| 203 | statically. |
| 204 | |
Eric Fiselier | bb856cc | 2015-10-15 22:41:51 +0000 | [diff] [blame] | 205 | .. option:: LIBCXX_ENABLE_ABI_LINKER_SCRIPT:BOOL |
| 206 | |
| 207 | **Default**: ``ON`` by default on UNIX platforms other than Apple unless |
| 208 | 'LIBCXX_ENABLE_STATIC_ABI_LIBRARY' is ON. Otherwise the default value is ``OFF``. |
| 209 | |
| 210 | This option generate and installs a linker script as ``libc++.so`` which |
| 211 | links the correct ABI library. |
| 212 | |
Eric Fiselier | b9f425a | 2015-08-22 19:40:49 +0000 | [diff] [blame] | 213 | .. option:: LIBCXXABI_USE_LLVM_UNWINDER:BOOL |
| 214 | |
| 215 | **Default**: ``OFF`` |
| 216 | |
| 217 | Build and use the LLVM unwinder. Note: This option can only be used when |
| 218 | libc++abi is the C++ ABI library used. |
| 219 | |
| 220 | |
| 221 | libc++ Feature options |
| 222 | ---------------------- |
| 223 | |
| 224 | .. option:: LIBCXX_ENABLE_EXCEPTIONS:BOOL |
| 225 | |
| 226 | **Default**: ``ON`` |
| 227 | |
| 228 | Build libc++ with exception support. |
| 229 | |
| 230 | .. option:: LIBCXX_ENABLE_RTTI:BOOL |
| 231 | |
| 232 | **Default**: ``ON`` |
| 233 | |
| 234 | Build libc++ with run time type information. |
| 235 | |
Evgeniy Stepanov | 4f01aa8 | 2015-10-13 23:48:28 +0000 | [diff] [blame] | 236 | |
| 237 | libc++ Feature options |
| 238 | ---------------------- |
| 239 | |
| 240 | The following options allow building libc++ for a different ABI version. |
| 241 | |
| 242 | .. option:: LIBCXX_ABI_VERSION:STRING |
| 243 | |
| 244 | **Default**: ``1`` |
| 245 | |
| 246 | Defines the target ABI version of libc++. |
| 247 | |
| 248 | .. option:: LIBCXX_ABI_UNSTABLE:BOOL |
| 249 | |
| 250 | **Default**: ``OFF`` |
| 251 | |
| 252 | Build the "unstable" ABI version of libc++. Includes all ABI changing features |
| 253 | on top of the current stable version. |
| 254 | |
Eric Fiselier | b9f425a | 2015-08-22 19:40:49 +0000 | [diff] [blame] | 255 | .. _LLVM-specific variables: |
| 256 | |
| 257 | LLVM-specific options |
| 258 | --------------------- |
| 259 | |
| 260 | .. option:: LLVM_LIBDIR_SUFFIX:STRING |
| 261 | |
| 262 | Extra suffix to append to the directory where libraries are to be |
| 263 | installed. On a 64-bit architecture, one could use ``-DLLVM_LIBDIR_SUFFIX=64`` |
| 264 | to install libraries to ``/usr/lib64``. |
| 265 | |
| 266 | .. option:: LLVM_BUILD_32_BITS:BOOL |
| 267 | |
| 268 | Build 32-bits executables and libraries on 64-bits systems. This option is |
| 269 | available only on some 64-bits unix systems. Defaults to OFF. |
| 270 | |
| 271 | .. option:: LLVM_LIT_ARGS:STRING |
| 272 | |
| 273 | Arguments given to lit. ``make check`` and ``make clang-test`` are affected. |
| 274 | By default, ``'-sv --no-progress-bar'`` on Visual C++ and Xcode, ``'-sv'`` on |
| 275 | others. |
| 276 | |
| 277 | |
| 278 | Using Alternate ABI libraries |
| 279 | ============================= |
| 280 | |
| 281 | |
| 282 | .. _libsupcxx: |
| 283 | |
| 284 | Using libsupc++ on Linux |
| 285 | ------------------------ |
| 286 | |
| 287 | You will need libstdc++ in order to provide libsupc++. |
| 288 | |
| 289 | Figure out where the libsupc++ headers are on your system. On Ubuntu this |
| 290 | is ``/usr/include/c++/<version>`` and ``/usr/include/c++/<version>/<target-triple>`` |
| 291 | |
| 292 | You can also figure this out by running |
| 293 | |
| 294 | .. code-block:: bash |
| 295 | |
| 296 | $ echo | g++ -Wp,-v -x c++ - -fsyntax-only |
| 297 | ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu" |
| 298 | ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/4.7/../../../../x86_64-linux-gnu/include" |
| 299 | #include "..." search starts here: |
| 300 | #include <...> search starts here: |
| 301 | /usr/include/c++/4.7 |
| 302 | /usr/include/c++/4.7/x86_64-linux-gnu |
| 303 | /usr/include/c++/4.7/backward |
| 304 | /usr/lib/gcc/x86_64-linux-gnu/4.7/include |
| 305 | /usr/local/include |
| 306 | /usr/lib/gcc/x86_64-linux-gnu/4.7/include-fixed |
| 307 | /usr/include/x86_64-linux-gnu |
| 308 | /usr/include |
| 309 | End of search list. |
| 310 | |
| 311 | Note that the first two entries happen to be what we are looking for. This |
| 312 | may not be correct on other platforms. |
| 313 | |
| 314 | We can now run CMake: |
| 315 | |
| 316 | .. code-block:: bash |
| 317 | |
| 318 | $ CC=clang CXX=clang++ cmake -G "Unix Makefiles" \ |
| 319 | -DLIBCXX_CXX_ABI=libstdc++ \ |
| 320 | -DLIBCXX_CXX_ABI_INCLUDE_PATHS="/usr/include/c++/4.7/;/usr/include/c++/4.7/x86_64-linux-gnu/" \ |
| 321 | -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr \ |
| 322 | <libc++-source-dir> |
| 323 | |
| 324 | |
| 325 | You can also substitute ``-DLIBCXX_CXX_ABI=libsupc++`` |
| 326 | above, which will cause the library to be linked to libsupc++ instead |
| 327 | of libstdc++, but this is only recommended if you know that you will |
| 328 | never need to link against libstdc++ in the same executable as libc++. |
| 329 | GCC ships libsupc++ separately but only as a static library. If a |
| 330 | program also needs to link against libstdc++, it will provide its |
| 331 | own copy of libsupc++ and this can lead to subtle problems. |
| 332 | |
| 333 | .. code-block:: bash |
| 334 | |
| 335 | $ make cxx |
| 336 | $ make install |
| 337 | |
| 338 | You can now run clang with -stdlib=libc++. |