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  10 <div class="doc_title">LLVM Makefile Guide</div>
  11
  12 <ol>
  13   <li><a href="#introduction">Introduction</a></li>
  14   <li><a href="#general">General Concepts</a>
  15     <ol>
  16       <li><a href="#projects">Projects</a></li>
  17       <li><a href="#varvals">Variable Values</a></li>
  18       <li><a href="#including">Including Makefiles</a>
  19         <ol>
  20           <li><a href="#Makefile">Makefile</a></li>
  21           <li><a href="#Makefile.common">Makefile.common</a></li>
  22           <li><a href="#Makefile.config">Makefile.config</a></li>
  23           <li><a href="#Makefile.rules">Makefile.rules</a></li>
  24         </ol>
  25       </li>
  26       <li><a href="#Comments">Comments</a></li>
  27     </ol>
  28   </li>
  29   <li><a href="#tutorial">Tutorial</a>
  30     <ol>
  31       <li><a href="#libraries">Libraries</a>
  32         <ol>
  33           <li><a href="#BCModules">Bytecode Modules</a></li>
  34           <li><a href="#LoadableModules">Loadable Modules</a></li>
  35         </ol>
  36       </li>
  37       <li><a href="#tools">Tools</a>
  38         <ol>
  39           <li><a href="#JIT">JIT Tools</a></li>
  40         </ol>
  41       </li>
  42       <li><a href="#projects">Projects</a></li>
  43     </ol>
  44   </li>
  45   <li><a href="#targets">Targets Supported</a>
  46     <ol>
  47       <li><a href="#all">all</a></li>
  48       <li><a href="#all-local">all-local</a></li>
  49       <li><a href="#check">check</a></li>
  50       <li><a href="#check-local">check-local</a></li>
  51       <li><a href="#clean">clean</a></li>
  52       <li><a href="#clean-local">clean-local</a></li>
  53       <li><a href="#dist">dist</a></li>
  54       <li><a href="#dist-check">dist-check</a></li>
  55       <li><a href="#dist-clean">dist-clean</a></li>
  56       <li><a href="#install">install</a></li>
  57       <li><a href="#preconditions">preconditions</a></li>
  58       <li><a href="#printvars">printvars</a></li>
  59       <li><a href="#reconfigure">reconfigure</a></li>
  60       <li><a href="#spotless">spotless</a></li>
  61       <li><a href="#tags">tags</a></li>
  62       <li><a href="#uninstall">uninstall</a></li>
  63     </ol>
  64   </li>
  65   <li><a href="#variables">Using Variables</a>
  66     <ol>
  67       <li><a href="#setvars">Control Variables</a></li>
  68       <li><a href="#overvars">Override Variables</a></li>
  69       <li><a href="#getvars">Readable Variables</a></li>
  70       <li><a href="#intvars">Internal Variables</a></li>
  71     </ol>
  72   </li>
  73 </ol>
  74
  75 <div class="doc_author">
  76   <p>Written by <a href="mailto:reid@x10sys.com">Reid Spencer</a></p>
  77 </div>
  78
  79 <!-- *********************************************************************** -->
  80 <div class="doc_section"><a name="introduction">Introduction </a></div>
  81 <!-- *********************************************************************** -->
  82
  83 <div class="doc_text">
  84   <p>This document provides <em>usage</em> information about the LLVM makefile
  85   system. While loosely patterned after the BSD makefile system, LLVM has taken
  86   a departure from BSD in order to implement additional features needed by LLVM.
  87   Although makefile systems such as automake were attempted at one point, it
  88   has become clear that the features needed by LLVM and the Makefile norm are
  89   too great to use a more limited tool. Consequently, LLVM requires simply GNU
  90   Make 3.79, a widely portable makefile processor. LLVM unabashedly makes heavy
  91   use of the features of GNU Make so the dependency on GNU Make is firm. If
  92   you're not familiar with <tt>make</tt>, it is recommended that you read the
  93   <a href="http://www.gnu.org/software/make/manual/make.html">GNU Makefile
  94   Manual</a>.</p>
  95   <p>While this document is rightly part of the
  96   <a href="ProgrammersManual.html">LLVM Programmer's Manual</a>, it is treated
  97   separately here because of the volume of content and because it is often an
  98   early source of bewilderment for new developers.</p>
  99 </div>
 100
 101 <!-- *********************************************************************** -->
 102 <div class="doc_section"><a name="general">General Concepts</a></div>
 103 <!-- *********************************************************************** -->
 104
 105 <div class="doc_text">
 106   <p>The LLVM Makefile System is the component of LLVM that is responsible for
 107   building the software, testing it,  generating distributions, checking those
 108   distributions, installing and uninstalling, etc. It consists of a several
 109   files throughout the source tree. These files and other general concepts are
 110   described in this section.</p>
 111 </div>
 112
 113 <!-- ======================================================================= -->
 114 <div class="doc_subsection"><a name="projects">Projects</a></div>
 115 <div class="doc_text">
 116   <p>The LLVM Makefile System is quite generous. It not only builds its own
 117   software, but it can build yours too. Built into the system is knowledge of
 118   the <tt>llvm/projects</tt> directory. Any directory under <tt>projects</tt>
 119   that has both a <tt>configure</tt> script and a <tt>Makefile</tt> is assumed
 120   to be a project that uses the LLVM Makefile system.  Building software that
 121   uses LLVM does not require the LLVM Makefile System nor even placement in the
 122   <tt>llvm/projects</tt> directory. However, doing so will allow your project
 123   to get up and running quickly by utilizing the built-in features that are used
 124   to compile LLVM. LLVM compiles itself using the same features of the makefile
 125   system as used for projects.</p>
 126   <p>For complete details on setting up your projects configuration, simply
 127   mimic the <tt>llvm/projects/sample</tt> project or for further details,
 128   consult the <a href="Projects.html">Projects.html</a> page.</p>
 129 </div>
 130
 131 <!-- ======================================================================= -->
 132 <div class="doc_subsection"><a name="varvalues">Variable Values</a></div>
 133 <div class="doc_text">
 134   <p>To use the makefile system, you simply create a file named
 135   <tt>Makefile</tt> in your directory and declare values for certain variables.
 136   The variables and values that you select determine what the makefile system
 137   will do. These variables enable rules and processing in the makefile system
 138   that automatically Do The Right Thing&trade;.
 139 </div>
 140
 141 <!-- ======================================================================= -->
 142 <div class="doc_subsection"><a name="including">Including Makefiles</a></div>
 143 <div class="doc_text">
 144   <p>Setting variables alone is not enough. You must include into your Makefile
 145   additional files that provide the rules of the LLVM Makefile system. The
 146   various files involved are described in the sections that follow.</p>
 147 </div>
 148
 149 <!-- ======================================================================= -->
 150 <div class="doc_subsubsection"><a name="Makefile">Makefile</a></div>
 151 <div class="doc_text">
 152   <p>Each directory to participate in the build needs to have a file named
 153   <tt>Makefile</tt>. This is the file first read by <tt>make</tt>. It has three
 154   sections:</p>
 155   <ol>
 156     <li><a href="#setvars">Settable Variables</a> - Required that must be set
 157     first.</li>
 158     <li><a href="#Makefile.common">include <tt>$(LEVEL)/Makefile.common</tt></a>
 159     - include the LLVM Makefile system.
 160     <li><a href="#overvars">Override Variables</a> - Override variables set by
 161     the LLVM Makefile system.
 162   </ol>
 163 </div>
 164
 165 <!-- ======================================================================= -->
 166 <div class="doc_subsubsection"><a name="Makefile.common">Makefile.common</a>
 167 </div>
 168 <div class="doc_text">
 169   <p>Every project must have a <tt>Makefile.common</tt> file at its top source
 170   directory. This file serves three purposes:</p>
 171   <ol>
 172     <li>It includes the project's configuration makefile to obtain values
 173     determined by the <tt>configure</tt> script. This is done by including the
 174     <a href="#Makefile.config"><tt>$(LEVEL)/Makefile.config</tt></a> file.</li>
 175     <li>It specifies any other (static) values that are needed throughout the
 176     project. Only values that are used in all or a large proportion of the
 177     project's directories should be placed here.</li>
 178     <li>It includes the standard rules for the LLVM Makefile system,
 179     <a href="#Makefile.rules"><tt>$(LLVM_SRC_ROOT)/Makefile.rules</tt></a>.
 180     This file is the "guts" of the LLVM Makefile system.</li>
 181   </ol>
 182 </div>
 183
 184 <!-- ======================================================================= -->
 185 <div class="doc_subsubsection"><a name="Makefile.config">Makefile.config</a>
 186 </div>
 187 <div class="doc_text">
 188   <p>Every project must have a <tt>Makefile.config</tt> at the top of its
 189   <em>build</em> directory. This file is <b>generated</b> by the
 190   <tt>configure</tt> script from the pattern provided by the
 191   <tt>Makefile.config.in</tt> file located at the top of the project's
 192   <em>source</em> directory. The contents of this file depend largely on what
 193   configuration items the project uses, however most projects can get what they
 194   need by just relying on LLVM's configuration found in
 195   <tt>$(LLVM_OBJ_ROOT)/Makefile.config</tt>.
 196 </div>
 197
 198 <!-- ======================================================================= -->
 199 <div class="doc_subsubsection"><a name="Makefile.rules">Makefile.rules</a></div>
 200 <div class="doc_text">
 201   <p>This file, located at <tt>$(LLVM_SRC_ROOT)/Makefile.rules</tt> is the heart
 202   of the LLVM Makefile System. It provides all the logic, dependencies, and
 203   rules for building the targets supported by the system. What it does largely
 204   depends on the values of <tt>make</tt> <a href="#variables">variables</a> that
 205   have been set <em>before</em> <tt>Makefile.rules</tt> is included.
 206 </div>
 207
 208 <!-- ======================================================================= -->
 209 <div class="doc_subsection"><a name="Comments">Comments</a></div>
 210 <div class="doc_text">
 211   <p>User Makefiles need not have comments in them unless the construction is
 212   unusual or it does not strictly follow the rules and patterns of the LLVM
 213   makefile system. Makefile comments are invoked with the pound (#) character.
 214   The # character and any text following it, to the end of the line, are ignored
 215   by <tt>make</tt>.</p>
 216 </div>
 217
 218 <!-- *********************************************************************** -->
 219 <div class="doc_section"><a name="tutorial">Tutorial</a></div>
 220 <!-- *********************************************************************** -->
 221 <div class="doc_text">
 222   <p>This section provides some examples of the different kinds of modules you
 223   can build with the LLVM makefile system. In general, each directory you
 224   provide will build a single object although that object may be composed of
 225   additionally compiled components.</p>
 226 </div>
 227
 228 <!-- ======================================================================= -->
 229 <div class="doc_subsection"><a name="libraries">Libraries</a></div>
 230 <div class="doc_text">
 231   <p>Only a few variable definitions are needed to build a regular library.
 232   Normally, the makefile system will build all the software into a single
 233   <tt>libname.o</tt> (pre-linked) object. This means the library is not
 234   searchable and that the distinction between compilation units has been
 235   dissolved. Optionally, you can ask for a shared library (.so), archive library
 236   (.a) or to not have the default (relinked) library built. For example:</p>
 237   <pre><tt>
 238       LIBRARYNAME = mylib
 239       SHARED_LIBRARY = 1
 240       ARCHIVE_LIBRARY = 1
 241       DONT_BUILD_RELINKED = 1
 242   </tt></pre>
 243   <p>says to build a library named "mylib" with both a shared library
 244   (<tt>mylib.so</tt>) and an archive library (<tt>mylib.a</tt>) version but
 245   not to build the relinked object (<tt>mylib.o</tt>). The contents of all the
 246   libraries produced will be the same, they are just constructed differently.
 247   Note that you normally do not need to specify the sources involved. The LLVM
 248   Makefile system will infer the source files from the contents of the source
 249   directory.</p>
 250   <p>The <tt>LOADABLE_MODULE=1</tt> directive can be used in conjunction with
 251   <tt>SHARED_LIBRARY=1</tt> to indicate that the resulting shared library should
 252   be openable with the <tt>dlopen</tt> function and searchable with the
 253   <tt>dlsym</tt> function (or your operating system's equivalents). While this
 254   isn't strictly necessary on Linux and a few other platforms, it is required
 255   on systems like HP-UX and Darwin. You should use <tt>LOADABLE_MODULE</tt> for
 256   any shared library that you intend to be loaded into an tool via the
 257   <tt>-load</tt> option. See the
 258   <a href="WritingAnLLVMPass.html#makefile">WritingAnLLVMPass.html</a> document
 259   for an example of why you might want to do this.
 260 </div>
 261
 262 <!-- ======================================================================= -->
 263 <div class="doc_subsubsection"><a name="BCModules">Bytecode Modules</a></div>
 264 <div class="doc_text">
 265   <p>In some situations, it is desireable to build a single bytecode module from
 266   a variety of sources, instead of an archive, shared library, or bytecode
 267   library. Bytecode modules can be specified in addition to any of the other
 268   types of libraries by defining the <a href="#MODULE_NAME">MODULE_NAME</a>
 269   variable. For example:</p>
 270   <pre><tt>
 271       LIBRARYNAME = mylib
 272       BYTECODE_LIBRARY = 1
 273       MODULE_NAME = mymod
 274   </tt></pre>
 275   <p>will build a module named <tt>mymod.bc</tt> from the sources in the
 276   directory. This module will be an aggregation of all the bytecode modules
 277   derived from the sources. The example will also build a bytecode archive
 278   containing a bytecode module for each compiled source file. The difference is
 279   subtle, but important depending on how the module or library is to be linked.
 280   </p>
 281 </div>
 282
 283 <!-- ======================================================================= -->
 284 <div class="doc_subsubsection">
 285   <a name="LoadableModules">Loadable Modules</a>
 286 </div>
 287 <div class="doc_text">
 288   <p>In some situations, you need to create a loadable module. Loadable modules
 289   can be loaded into programs like <tt>opt</tt> or <tt>llc</tt> to specify
 290   additional passes to run or targets to support.  Loadable modules are also
 291   useful for debugging a pass or providing a pass with another package if that
 292   pass can't be included in LLVM.</p>
 293   <p>LLVM provides complete support for building such a module. All you need to
 294   do is use the LOADABLE_MODULE variable in your Makefile. For example, to
 295   build a loadable module named <tt>MyMod</tt> that uses the LLVM libraries
 296   <tt>LLVMSupport.a</tt> and <tt>LLVMSystem.a</tt>, you would specify:</p>
 297   <pre><tt>
 298      LIBRARYNAME := MyMod
 299      LOADABLE_MODULE := 1
 300      LINK_COMPONENTS := support system
 301   </tt></pre>
 302   <p>Use of the <tt>LOADABLE_MODULE</tt> facility implies several things:</p>
 303   <ol>
 304     <li>There will be no "lib" prefix on the module. This differentiates it from
 305     a standard shared library of the same name.</li>
 306     <li>The <a href="#SHARED_LIBRARY">SHARED_LIBRARY</a> variable is turned
 307     on.</li>
 308     <li>The <a href="#LINK_LIBS_IN_SHARED">LINK_LIBS_IN_SHARED</a> variable
 309     is turned on.</li>
 310     <li>The <a href="#DONT_BUILD_RELINKED">DONT_BUILD_RELINKED</a> variable
 311     is turned on.</li>
 312   </ol>
 313   <p>A loadable module is loaded by LLVM via the facilities of libtool's libltdl
 314   library which is part of <tt>lib/System</tt> implementation.</p>
 315 </div>
 316
 317 <!-- ======================================================================= -->
 318 <div class="doc_subsection"><a name="tools">Tools</a></div>
 319 <div class="doc_text">
 320   <p>For building executable programs (tools), you must provide the name of the
 321   tool and the names of the libraries you wish to link with the tool. For
 322   example:</p>
 323   <pre><tt>
 324       TOOLNAME = mytool
 325       USEDLIBS = mylib
 326       LINK_COMPONENTS = support system
 327   </tt></pre>
 328   <p>says that we are to build a tool name <tt>mytool</tt> and that it requires
 329   three libraries: <tt>mylib</tt>, <tt>LLVMSupport.a</tt> and
 330   <tt>LLVMSystem.a</tt>.</p>
 331   <p>Note that two different variables are use to indicate which libraries are
 332   linked: <tt>USEDLIBS</tt> and <tt>LLVMLIBS</tt>. This distinction is necessary
 333   to support projects. <tt>LLVMLIBS</tt> refers to the LLVM libraries found in
 334   the LLVM object directory. <tt>USEDLIBS</tt> refers to the libraries built by
 335   your project. In the case of building LLVM tools, <tt>USEDLIBS</tt> and
 336   <tt>LLVMLIBS</tt> can be used interchangeably since the "project" is LLVM
 337   itself and <tt>USEDLIBS</tt> refers to the same place as <tt>LLVMLIBS</tt>.
 338   </p>
 339   <p>Also note that there are two different ways of specifying a library: with a
 340   <tt>.a</tt> suffix and without. Without the suffix, the entry refers to the
 341   re-linked (.o) file which will include <em>all</em> symbols of the library.
 342   This is useful, for example, to include all passes from a library of passes.
 343   If the <tt>.a</tt> suffix is used then the library is linked as a searchable
 344   library (with the <tt>-l</tt> option). In this case, only the symbols that are
 345   unresolved <em>at that point</em> will be resolved from the library, if they
 346   exist. Other (unreferenced) symbols will not be included when the <tt>.a</tt>
 347   syntax is used. Note that in order to use the <tt>.a</tt> suffix, the library
 348   in question must have been built with the <tt>ARCHIVE_LIBRARY</tt> option set.
 349   </p>
 350 </div>
 351
 352 <!-- ======================================================================= -->
 353 <div class="doc_subsubsection"><a name="JIT">JIT Tools</a></div>
 354 <div class="doc_text">
 355   <p>Many tools will want to use the JIT features of LLVM.  To do this, you
 356      simply specify that you want an execution 'engine', and the makefiles will
 357      automatically link in the appropriate JIT for the host or an interpreter
 358      if none is available:</p>
 359   <pre><tt>
 360       TOOLNAME = my_jit_tool
 361       USEDLIBS = mylib
 362       LINK_COMPONENTS = engine
 363   </tt></pre>
 364   <p>Of course, any additional libraries may be listed as other components.  To
 365   get a full understanding of how this changes the linker command, it is
 366   recommended that you:</p>
 367   <pre><tt>
 368       cd examples/Fibonacci
 369       make VERBOSE=1
 370   </tt></pre>
 371 </div>
 372
 373 <!-- *********************************************************************** -->
 374 <div class="doc_section"><a name="targets">Targets Supported</a></div>
 375 <!-- *********************************************************************** -->
 376
 377 <div class="doc_text">
 378   <p>This section describes each of the targets that can be built using the LLVM
 379   Makefile system. Any target can be invoked from any directory but not all are
 380   applicable to a given directory (e.g. "check", "dist" and "install" will
 381   always operate as if invoked from the top level directory).</p>
 382
 383   <table style="text-align:left">
 384     <tr>
 385       <th>Target Name</th><th>Implied Targets</th><th>Target Description</th>
 386     </tr>
 387     <tr><td><a href="#all"><tt>all</tt></a></td><td></td>
 388       <td>Compile the software recursively. Default target.
 389     </td></tr>
 390     <tr><td><a href="#all-local"><tt>all-local</tt></a></td><td></td>
 391       <td>Compile the software in the local directory only.
 392     </td></tr>
 393     <tr><td><a href="#check"><tt>check</tt></a></td><td></td>
 394       <td>Change to the <tt>test</tt> directory in a project and run the
 395       test suite there.
 396     </td></tr>
 397     <tr><td><a href="#check-local"><tt>check-local</tt></a></td><td></td>
 398       <td>Run a local test suite. Generally this is only defined in the
 399         <tt>Makefile</tt> of the project's <tt>test</tt> directory.
 400     </td></tr>
 401     <tr><td><a href="#clean"><tt>clean</tt></a></td><td></td>
 402       <td>Remove built objects recursively.
 403     </td></tr>
 404     <tr><td><a href="#clean-local"><tt>clean-local</tt></a></td><td></td>
 405       <td>Remove built objects from the local directory only.
 406     </td></tr>
 407     <tr><td><a href="#dist"><tt>dist</tt></a></td><td>all</td>
 408       <td>Prepare a source distribution tarball.
 409     </td></tr>
 410     <tr><td><a href="#dist-check"><tt>dist-check</tt></a></td><td>all</td>
 411       <td>Prepare a source distribution tarball and check that it builds.
 412     </td></tr>
 413     <tr><td><a href="#dist-clean"><tt>dist-clean</tt></a></td><td>clean</td>
 414       <td>Clean source distribution tarball temporary files.
 415     </td></tr>
 416     <tr><td><a href="#install"><tt>install</tt></a></td><td>all</td>
 417       <td>Copy built objects to installation directory.
 418     </td></tr>
 419     <tr><td><a href="#preconditions"><tt>preconditions</tt></a></td><td>all</td>
 420       <td>Check to make sure configuration and makefiles are up to date.
 421     </td></tr>
 422     <tr><td><a href="#printvars"><tt>printvars</tt></a></td><td>all</td>
 423       <td>Prints variables defined by the makefile system (for debugging).
 424     </td></tr>
 425     <tr><td><a href="#tags"><tt>tags</tt></a></td><td></td>
 426       <td>Make C and C++ tags files for emacs and vi.
 427     </td></tr>
 428     <tr><td><a href="#uninstall"><tt>uninstall</tt></a></td><td></td>
 429       <td>Remove built objects from installation directory.
 430     </td></tr>
 431   </table>
 432 </div>
 433
 434 <!-- ======================================================================= -->
 435 <div class="doc_subsection"><a name="all">all (default)</a></div>
 436 <div class="doc_text">
 437   <p>When you invoke <tt>make</tt> with no arguments, you are implicitly
 438   instructing it to seek the "all" target (goal). This target is used for
 439   building the software recursively and will do different things in different
 440   directories.  For example, in a <tt>lib</tt> directory, the "all" target will
 441   compile source files and generate libraries. But, in a <tt>tools</tt>
 442   directory, it will link libraries and generate executables.</p>
 443 </div>
 444
 445 <!-- ======================================================================= -->
 446 <div class="doc_subsection"><a name="all-local">all-local</a></div>
 447 <div class="doc_text">
 448   <p>This target is the same as <a href="#all">all</a> but it operates only on
 449   the current directory instead of recursively.</p>
 450 </div>
 451
 452 <!-- ======================================================================= -->
 453 <div class="doc_subsection"><a name="check">check</a></div>
 454 <div class="doc_text">
 455   <p>This target can be invoked from anywhere within a project's directories
 456   but always invokes the <a href="#check-local"><tt>check-local</tt></a> target
 457   in the project's <tt>test</tt> directory, if it exists and has a
 458   <tt>Makefile</tt>. A warning is produced otherwise.  If
 459   <a href="#TESTSUITE"><tt>TESTSUITE</tt></a> is defined on the <tt>make</tt>
 460   command line, it will be passed down to the invocation of
 461   <tt>make check-local</tt> in the <tt>test</tt> directory. The intended usage
 462   for this is to assist in running specific suites of tests. If
 463   <tt>TESTSUITE</tt> is not set, the implementation of <tt>check-local</tt>
 464   should run all normal tests.  It is up to the project to define what
 465   different values for <tt>TESTSUTE</tt> will do. See the
 466   <a href="TestingGuide.html">TestingGuide</a> for further details.</p>
 467 </div>
 468
 469 <!-- ======================================================================= -->
 470 <div class="doc_subsection"><a name="check-local">check-local</a></div>
 471 <div class="doc_text">
 472   <p>This target should be implemented by the <tt>Makefile</tt> in the project's
 473   <tt>test</tt> directory. It is invoked by the <tt>check</tt> target elsewhere.
 474   Each project is free to define the actions of <tt>check-local</tt> as
 475   appropriate for that project. The LLVM project itself uses dejagnu to run a
 476   suite of feature and regresson tests. Other projects may choose to use
 477   dejagnu or any other testing mechanism.</p>
 478 </div>
 479
 480 <!-- ======================================================================= -->
 481 <div class="doc_subsection"><a name="clean">clean</a></div>
 482 <div class="doc_text">
 483   <p>This target cleans the build directory, recursively removing all things
 484   that the Makefile builds. The cleaning rules have been made guarded so they
 485   shouldn't go awry (via <tt>rm -f $(UNSET_VARIABLE)/*</tt> which will attempt
 486   to erase the entire directory structure.</p>
 487 </div>
 488
 489 <!-- ======================================================================= -->
 490 <div class="doc_subsection"><a name="clean-local">clean-local</a></div>
 491 <div class="doc_text">
 492   <p>This target does the same thing as <tt>clean</tt> but only for the current
 493   (local) directory.</p>
 494 </div>
 495
 496 <!-- ======================================================================= -->
 497 <div class="doc_subsection"><a name="dist">dist</a></div>
 498 <div class="doc_text">
 499   <p>This target builds a distribution tarball. It first builds the entire
 500   project using the <tt>all</tt> target and then tars up the necessary files and
 501   compresses it. The generated tarball is sufficient for a casual source
 502   distribution, but probably not for a release (see <tt>dist-check</tt>).</p>
 503 </div>
 504
 505 <!-- ======================================================================= -->
 506 <div class="doc_subsection"><a name="dist-check">dist-check</a></div>
 507 <div class="doc_text">
 508   <p>This target does the same thing as the <tt>dist</tt> target but also checks
 509   the distribution tarball. The check is made by unpacking the tarball to a new
 510   directory, configuring it, building it, installing it, and then verifying that
 511   the installation results are correct (by comparing to the original build).
 512   This target can take a long time to run but should be done before a release
 513   goes out to make sure that the distributed tarball can actually be built into
 514   a working release.</p>
 515 </div>
 516
 517 <!-- ======================================================================= -->
 518 <div class="doc_subsection"><a name="dist-clean">dist-clean</a></div>
 519 <div class="doc_text">
 520   <p>This is a special form of the <tt>clean</tt> clean target. It performs a
 521   normal <tt>clean</tt> but also removes things pertaining to building the
 522   distribution.</p>
 523 </div>
 524
 525 <!-- ======================================================================= -->
 526 <div class="doc_subsection"><a name="install">install</a></div>
 527 <div class="doc_text">
 528   <p>This target finalizes shared objects and executables and copies all
 529   libraries, headers, executables and documentation to the directory given
 530   with the <tt>--prefix</tt> option to <tt>configure</tt>.  When completed,
 531   the prefix directory will have everything needed to <b>use</b> LLVM. </p>
 532   <p>The LLVM makefiles can generate complete <b>internal</b> documentation
 533   for all the classes by using <tt>doxygen</tt>. By default, this feature is
 534   <b>not</b> enabled because it takes a long time and generates a massive
 535   amount of data (>100MB). If you want this feature, you must configure LLVM
 536   with the --enable-doxygen switch and ensure that a modern version of doxygen
 537   (1.3.7 or later) is available in your <tt>PATH</tt>. You can download
 538   doxygen from
 539   <a href="http://www.stack.nl/~dimitri/doxygen/download.html#latestsrc">
 540   here</a>.
 541 </div>
 542
 543 <!-- ======================================================================= -->
 544 <div class="doc_subsection"><a name="preconditions">preconditions</a></div>
 545 <div class="doc_text">
 546   <p>This utility target checks to see if the <tt>Makefile</tt> in the object
 547   directory is older than the <tt>Makefile</tt> in the source directory and
 548   copies it if so. It also reruns the <tt>configure</tt> script if that needs to
 549   be done and rebuilds the <tt>Makefile.config</tt> file similarly. Users may
 550   overload this target to ensure that sanity checks are run <em>before</em> any
 551   building of targets as all the targets depend on <tt>preconditions</tt>.</p>
 552 </div>
 553
 554 <!-- ======================================================================= -->
 555 <div class="doc_subsection"><a name="printvars">printvars</a></div>
 556 <div class="doc_text">
 557   <p>This utility target just causes the LLVM makefiles to print out some of
 558   the makefile variables so that you can double check how things are set. </p>
 559 </div>
 560
 561 <!-- ======================================================================= -->
 562 <div class="doc_subsection"><a name="reconfigure">reconfigure</a></div>
 563 <div class="doc_text">
 564   <p>This utility target will force a reconfigure of LLVM or your project. It
 565   simply runs <tt>$(PROJ_OBJ_ROOT)/config.status --recheck</tt> to rerun the
 566   configuration tests and rebuild the configured files. This isn't generally
 567   useful as the makefiles will reconfigure themselves whenever its necessary.
 568   </p>
 569 </div>
 570
 571 <!-- ======================================================================= -->
 572 <div class="doc_subsection"><a name="spotless">spotless</a></div>
 573 <div class="doc_text">
 574   <p>This utility target, only available when <tt>$(PROJ_OBJ_ROOT)</tt> is not
 575   the same as <tt>$(PROJ_SRC_ROOT)</tt>, will completely clean the
 576   <tt>$(PROJ_OBJ_ROOT)</tt> directory by removing its content entirely and
 577   reconfiguring the directory. This returns the <tt>$(PROJ_OBJ_ROOT)</tt>
 578   directory to a completely fresh state. All content in the directory except
 579   configured files and top-level makefiles will be lost.</p>
 580   <div class="doc_warning"><p>Use with caution.</p></div>
 581 </div>
 582
 583 <!-- ======================================================================= -->
 584 <div class="doc_subsection"><a name="tags">tags</a></div>
 585 <div class="doc_text">
 586   <p>This target will generate a <tt>TAGS</tt> file in the top-level source
 587   directory. It is meant for use with emacs, XEmacs, or ViM. The TAGS file
 588   provides an index of symbol definitions so that the editor can jump you to the
 589   definition quickly. </p>
 590 </div>
 591
 592 <!-- ======================================================================= -->
 593 <div class="doc_subsection"><a name="uninstall">uninstall</a></div>
 594 <div class="doc_text">
 595   <p>This target is the opposite of the <tt>install</tt> target. It removes the
 596   header, library and executable files from the installation directories. Note
 597   that the directories themselves are not removed because it is not guaranteed
 598   that LLVM is the only thing installing there (e.g. --prefix=/usr).</p>
 599 </div>
 600
 601 <!-- *********************************************************************** -->
 602 <div class="doc_section"><a name="variables">Variables</a></div>
 603 <!-- *********************************************************************** -->
 604 <div class="doc_text">
 605   <p>Variables are used to tell the LLVM Makefile System what to do and to
 606   obtain information from it. Variables are also used internally by the LLVM
 607   Makefile System. Variable names that contain only the upper case alphabetic
 608   letters and underscore are intended for use by the end user. All other
 609   variables are internal to the LLVM Makefile System and should not be relied
 610   upon nor modified. The sections below describe how to use the LLVM Makefile
 611   variables.</p>
 612 </div>
 613
 614 <!-- ======================================================================= -->
 615 <div class="doc_subsection"><a name="setvars">Control Variables</a></div>
 616 <div class="doc_text">
 617   <p>Variables listed in the table below should be set <em>before</em> the
 618   inclusion of <a href="#Makefile.common"><tt>$(LEVEL)/Makefile.common</tt></a>.
 619   These variables provide input to the LLVM make system that tell it what to do
 620   for the current directory.</p>
 621   <dl>
 622     <dt><a name="BUILD_ARCHIVE"><tt>BUILD_ARCHIVE</tt></a></dt>
 623     <dd>If set to any value, causes an archive (.a) library to be built.</dd>
 624     <dt><a name="BUILT_SOURCES"><tt>BUILT_SOURCES</tt></a></dt>
 625     <dd>Specifies a set of source files that are generated from other source
 626     files. These sources will be built before any other target processing to
 627     ensure they are present.</dd>
 628     <dt><a name="BYTECODE_LIBRARY"><tt>BYTECODE_LIBRARY</tt></a></dt>
 629     <dd>If set to any value, causes a bytecode library (.bc) to be built.</dd>
 630     <dt><a name="CONFIG_FILES"><tt>CONFIG_FILES</tt></a></dt>
 631     <dd>Specifies a set of configuration files to be installed.</dd>
 632     <dt><a name="DIRS"><tt>DIRS</tt></a></dt>
 633     <dd>Specifies a set of directories, usually children of the current
 634     directory, that should also be made using the same goal. These directories
 635     will be built serially.</dd>
 636     <dt><a name="DISABLE_AUTO_DEPENDENCIES"><tt>DISABLE_AUTO_DEPENDENCIES</tt></a></dt>
 637     <dd>If set to any value, causes the makefiles to <b>not</b> automatically
 638     generate dependencies when running the compiler. Use of this feature is
 639     discouraged and it may be removed at a later date.</dd>
 640     <dt><a name="DONT_BUILD_RELINKED"><tt>DONT_BUILD_RELINKED</tt></a></dt>
 641     <dd>If set to any value, causes a relinked library (.o) not to be built. By
 642     default, libraries are built as re-linked since most LLVM libraries are
 643     needed in their entirety and re-linked libraries will be linked more quickly
 644     than equivalent archive libraries.</dd>
 645     <dt><a name="ENABLE_OPTIMIZED"><tt>ENABLE_OPTIMIZED</tt></a></dt>
 646     <dd>If set to any value, causes the build to generate optimized objects,
 647     libraries and executables. This alters the flags specified to the compilers
 648     and linkers. Generally debugging won't be a fun experience with an optimized
 649     build.</dd>
 650     <dt><a name="ENABLE_PROFILING"><tt>ENABLE_PROFILING</tt></a></dt>
 651     <dd>If set to any value, causes the build to generate both optimized and
 652     profiled objects, libraries and executables. This alters the flags specified
 653     to the compilers and linkers to ensure that profile data can be collected
 654     from the tools built. Use the <tt>gprof</tt> tool to analyze the output from
 655     the profiled tools (<tt>gmon.out</tt>).</dd>
 656     <dt><a name="DISABLE_ASSERTIONS"><tt>DISABLE_ASSERTIONS</tt></a></dt>
 657     <dd>If set to any value, causes the build to disable assertions, even if
 658     building a release or profile build.  This will exclude all assertion check
 659     code from the build. LLVM will execute faster, but with little help when
 660     things go wrong.</dd>
 661     <dt><a name="EXPERIMENTAL_DIRS"><tt>EXPERIMENTAL_DIRS</tt></a></dt>
 662     <dd>Specify a set of directories that should be built, but if they fail, it
 663     should not cause the build to fail. Note that this should only be used
 664     temporarily while code is being written.</dd>
 665     <dt><a name="EXPORTED_SYMBOL_FILE"><tt>EXPORTED_SYMBOL_FILE</tt></a></dt>
 666     <dd>Specifies the name of a single file that contains a list of the
 667     symbols to be exported by the linker. One symbol per line.</dd>
 668     <dt><a name="EXPORTED_SYMBOL_LIST"><tt>EXPORTED_SYMBOL_LIST</tt></a></dt>
 669     <dd>Specifies a set of symbols to be exported by the linker.</dd>
 670     <dt><a name="EXTRA_DIST"><tt>EXTRA_DIST</tt></a></dt>
 671     <dd>Specifies additional files that should be distributed with LLVM. All
 672     source files, all built sources, all Makefiles, and most documentation files
 673     will be automatically distributed. Use this variable to distribute any
 674     files that are not automatically distributed.</dd>
 675     <dt><a name="KEEP_SYMBOLS"><tt>KEEP_SYMBOLS</tt></a></dt>
 676     <dd>If set to any value, specifies that when linking executables the
 677     makefiles should retain debug symbols in the executable. Normally, symbols
 678     are stripped from the executable.</dd>
 679     <dt><a name="LEVEL"><tt>LEVEL</tt></a><small>(required)</small></dt>
 680     <dd>Specify the level of nesting from the top level. This variable must be
 681     set in each makefile as it is used to find the top level and thus the other
 682     makefiles.</dd>
 683     <dt><a name="LIBRARYNAME"><tt>LIBRARYNAME</tt></a></dt>
 684     <dd>Specify the name of the library to be built. (Required For
 685     Libraries)</dd>
 686     <dt><a name="LINK_COMPONENTS"><tt>LINK_COMPONENTS</tt></a></dt>
 687     <dd>When specified for building a tool, the value of this variable will be
 688     passed to the <tt>llvm-config</tt> tool to generate a link line for the
 689     tool. Unlike <tt>USEDLIBS</tt> and <tt>LLVMLIBS</tt>, not all libraries need
 690     to be specified. The <tt>llvm-config</tt> tool will figure out the library
 691     dependencies and add any libraries that are needed. The <tt>USEDLIBS</tt>
 692     variable can still be used in conjunction with <tt>LINK_COMPONENTS</tt> so
 693     that additional project-specific libraries can be linked with the LLVM
 694     libraries specified by <tt>LINK_COMPONENTS</tt></dd>
 695     <dt><a name="LINK_LIBS_IN_SHARED"><tt>LINK_LIBS_IN_SHARED</tt></a></dt>
 696     <dd>By default, shared library linking will ignore any libraries specified
 697     with the <a href="LLVMLIBS">LLVMLIBS</a> or <a href="USEDLIBS">USEDLIBS</a>.
 698     This prevents shared libs from including things that will be in the LLVM
 699     tool the shared library will be loaded into. However, sometimes it is useful
 700     to link certain libraries into your shared library and this option enables
 701     that feature.</dd>
 702     <dt><a name="LLVMLIBS"><tt>LLVMLIBS</tt></a></dt>
 703     <dd>Specifies the set of libraries from the LLVM $(ObjDir) that will be
 704     linked into the tool or library.</dd>
 705     <dt><a name="LOADABLE_MODULE"><tt>LOADABLE_MODULE</tt></a></dt>
 706     <dd>If set to any value, causes the shared library being built to also be
 707     a loadable module. Loadable modules can be opened with the dlopen() function
 708     and searched with dlsym (or the operating system's equivalent). Note that
 709     setting this variable without also setting <tt>SHARED_LIBRARY</tt> will have
 710     no effect.</dd>
 711     <dt><a name="MODULE_NAME"><tt>MODULE_NAME</tt></a></dt>
 712     <dd>Specifies the name of a bytecode module to be created. A bytecode
 713     module can be specified in conjunction with other kinds of library builds
 714     or by itself. It constructs from the sources a single linked bytecode
 715     file.</dd>
 716     <dt><a name="NO_INSTALL"><tt>NO_INSTALL</tt></a></dt>
 717     <dd>Specifies that the build products of the directory should not be
 718     installed but should be built even if the <tt>install</tt> target is given.
 719     This is handy for directories that build libraries or tools that are only
 720     used as part of the build process, such as code generators (e.g.
 721     <tt>tblgen</tt>).</dd>
 722     <dt><a name="OPTIONAL_DIRS"><tt>OPTIONAL_DIRS</tt></a></dt>
 723     <dd>Specify a set of directories that may be built, if they exist, but its
 724     not an error for them not to exist.</dd>
 725     <dt><a name="PARALLEL_DIRS"><tt>PARALLEL_DIRS</tt></a></dt>
 726     <dd>Specify a set of directories to build recursively and in parallel if
 727     the -j option was used with <tt>make</tt>.</dd>
 728     <dt><a name="SHARED_LIBRARY"><tt>SHARED_LIBRARY</tt></a></dt>
 729     <dd>If set to any value, causes a shared library (.so) to be built in
 730     addition to any other kinds of libraries. Note that this option will cause
 731     all source files to be built twice: once with options for position
 732     independent code and once without. Use it only where you really need a
 733     shared library.</dd>
 734     <dt><a name="SOURCES"><tt>SOURCES</tt><small>(optional)</small></a></dt>
 735     <dd>Specifies the list of source files in the current directory to be
 736     built. Source files of any type may be specified (programs, documentation,
 737     config files, etc.). If not specified, the makefile system will infer the
 738     set of source files from the files present in the current directory.</dd>
 739     <dt><a name="SUFFIXES"><tt>SUFFIXES</tt></a></dt>
 740     <dd>Specifies a set of filename suffixes that occur in suffix match rules.
 741     Only set this if your local <tt>Makefile</tt> specifies additional suffix
 742     match rules.</dd>
 743     <dt><a name="TARGET"><tt>TARGET</tt></a></dt>
 744     <dd>Specifies the name of the LLVM code generation target that the
 745     current directory builds. Setting this variable enables additional rules to
 746     build <tt>.inc</tt> files from <tt>.td</tt> files. </dd>
 747     <dt><a name="TESTSUITE"><tt>TESTSUITE</tt></a></dt>
 748     <dd>Specifies the directory of tests to run in <tt>llvm/test</tt>.</dd>
 749     <dt><a name="TOOLNAME"><tt>TOOLNAME</tt></a></dt>
 750     <dd>Specifies the name of the tool that the current directory should
 751     build.</dd>
 752     <dt><a name="TOOL_VERBOSE"><tt>TOOL_VERBOSE</tt></a></dt>
 753     <dd>Implies VERBOSE and also tells each tool invoked to be verbose. This is
 754     handy when you're trying to see the sub-tools invoked by each tool invoked
 755     by the makefile. For example, this will pass <tt>-v</tt> to the GCC
 756     compilers which causes it to print out the command lines it uses to invoke
 757     sub-tools (compiler, assembler, linker).</dd>
 758     <dt><a name="USEDLIBS"><tt>USEDLIBS</tt></a></dt>
 759     <dd>Specifies the list of project libraries that will be linked into the
 760     tool or library.</dd>
 761     <dt><a name="VERBOSE"><tt>VERBOSE</tt></a></dt>
 762     <dd>Tells the Makefile system to produce detailed output of what it is doing
 763     instead of just summary comments. This will generate a LOT of output.</dd>
 764   </dl>
 765 </div>
 766
 767 <!-- ======================================================================= -->
 768 <div class="doc_subsection"><a name="overvars">Override Variables</a></div>
 769 <div class="doc_text">
 770   <p>Override variables can be used to override the default
 771   values provided by the LLVM makefile system. These variables can be set in
 772   several ways:</p>
 773   <ul>
 774     <li>In the environment (e.g. setenv, export) -- not recommended.</li>
 775     <li>On the <tt>make</tt> command line -- recommended.</li>
 776     <li>On the <tt>configure</tt> command line</li>
 777     <li>In the Makefile (only <em>after</em> the inclusion of <a
 778     href="#Makefile.common"><tt>$(LEVEL)/Makefile.common</tt></a>).</li>
 779   </ul>
 780   <p>The override variables are given below:</p>
 781   <dl>
 782     <dt><a name="AR"><tt>AR</tt></a> <small>(defaulted)</small></dt>
 783     <dd>Specifies the path to the <tt>ar</tt> tool.</dd>
 784     <dt><a name="BISON"><tt>BISON</tt></a><small>(configured)</small></dt>
 785     <dd>Specifies the path to the <tt>bison</tt> tool.</dd>
 786     <dt><a name="PROJ_OBJ_DIR"><tt>PROJ_OBJ_DIR</tt></a></dt>
 787     <dd>The directory into which the products of build rules will be placed.
 788     This might be the same as
 789     <a href="#PROJ_SRC_DIR"><tt>PROJ_SRC_DIR</tt></a> but typically is
 790     not.</dd>
 791     <dt><a name="PROJ_SRC_DIR"><tt>PROJ_SRC_DIR</tt></a></dt>
 792     <dd>The directory which contains the source files to be built.</dd>
 793     <dt><a name="BZIP2"><tt>BZIP2</tt></a><small>(configured)</small></dt>
 794     <dd>The path to the <tt>bzip2</tt> tool.</dd>
 795     <dt><a name="CC"><tt>CC</tt></a><small>(configured)</small></dt>
 796     <dd>The path to the 'C' compiler.</dd>
 797     <dt><a name="CFLAGS"><tt>CFLAGS</tt></a></dt>
 798     <dd>Additional flags to be passed to the 'C' compiler.</dd>
 799     <dt><a name="CXX"><tt>CXX</tt></a></dt>
 800     <dd>Specifies the path to the C++ compiler.</dd>
 801     <dt><a name="CXXFLAGS"><tt>CXXFLAGS</tt></a></dt>
 802     <dd>Additional flags to be passed to the C++ compiler.</dd>
 803     <dt><a name="DATE"><tt>DATE<small>(configured)</small></tt></a></dt>
 804     <dd>Specifies the path to the <tt>date</tt> program or any program that can
 805     generate the current date and time on its standard output</dd>
 806     <dt><a name="DOT"><tt>DOT</tt></a><small>(configured)</small></dt>
 807     <dd>Specifies the path to the <tt>dot</tt> tool or <tt>false</tt> if there
 808     isn't one.</dd>
 809     <dt><a name="ECHO"><tt>ECHO</tt></a><small>(configured)</small></dt>
 810     <dd>Specifies the path to the <tt>echo</tt> tool for printing output.</dd>
 811     <dt><a name="ETAGS"><tt>ETAGS</tt></a><small>(configured)</small></dt>
 812     <dd>Specifies the path to the <tt>etags</tt> tool.</dd>
 813     <dt><a name="ETAGSFLAGS"><tt>ETAGSFLAGS</tt></a><small>(configured)</small>
 814     </dt>
 815     <dd>Provides flags to be passed to the <tt>etags</tt> tool.</dd>
 816     <dt><a name="EXEEXT"><tt>EXEEXT</tt></a><small>(configured)</small></dt>
 817     <dd>Provides the extension to be used on executables built by the makefiles.
 818     The value may be empty on platforms that do not use file extensions for
 819     executables (e.g. Unix).</dd>
 820     <dt><a name="FLEX"><tt>FLEX</tt></a><small>(configured)</small></dt>
 821     <dd>Specifies the path to the <tt>flex</tt> tool.</dd>
 822     <dt><a name="INSTALL"><tt>INSTALL</tt></a><small>(configured)</small></dt>
 823     <dd>Specifies the path to the <tt>install</tt> tool.</dd>
 824     <dt><a name="LDFLAGS"><tt>LDFLAGS</tt></a><small>(configured)</small></dt>
 825     <dd>Allows users to specify additional flags to pass to the linker.</dd>
 826     <dt><a name="LIBS"><tt>LIBS</tt></a><small>(configured)</small></dt>
 827     <dd>The list of libraries that should be linked with each tool.</dd>
 828     <dt><a name="LIBTOOL"><tt>LIBTOOL</tt></a><small>(configured)</small></dt>
 829     <dd>Specifies the path to the <tt>libtool</tt> tool. This tool is renamed
 830     <tt>mklib</tt> by the <tt>configure</tt> script and always located in the
 831     <dt><a name="LLVMAS"><tt>LLVMAS</tt></a><small>(defaulted)</small></dt>
 832     <dd>Specifies the path to the <tt>llvm-as</tt> tool.</dd>
 833     <dt><a name="LLVMGCC"><tt>LLVMGCC</tt></a><small>(defaulted)</small></dt>
 834     <dd>Specifies the path to the LLVM version of the GCC 'C' Compiler</dd>
 835     <dt><a name="LLVMGXX"><tt>LLVMGXX</tt></a><small>(defaulted)</small></dt>
 836     <dd>Specifies the path to the LLVM version of the GCC C++ Compiler</dd>
 837     <dt><a name="LLVMLD"><tt>LLVMLD</tt></a><small>(defaulted)</small></dt>
 838     <dd>Specifies the path to the LLVM bytecode linker tool</dd>
 839     <dt><a name="LLVM_OBJ_ROOT"><tt>LLVM_OBJ_ROOT</tt></a><small>(configured)
 840     </small></dt>
 841     <dd>Specifies the top directory into which the output of the build is
 842     placed.</dd>
 843     <dt><a name="LLVM_SRC_ROOT"><tt>LLVM_SRC_ROOT</tt></a><small>(configured)
 844     </small></dt>
 845     <dd>Specifies the top directory in which the sources are found.</dd>
 846     <dt><a name="LLVM_TARBALL_NAME"><tt>LLVM_TARBALL_NAME</tt></a>
 847     <small>(configured)</small></dt>
 848     <dd>Specifies the name of the distribution tarball to create. This is
 849     configured from the name of the project and its version number.</dd>
 850     <dt><a name="MKDIR"><tt>MKDIR</tt></a><small>(defaulted)</small></dt>
 851     <dd>Specifies the path to the <tt>mkdir</tt> tool that creates
 852     directories.</dd>
 853     <dt><a name="PLATFORMSTRIPOPTS"><tt>PLATFORMSTRIPOPTS</tt></a></dt>
 854     <dd>The options to provide to the linker to specify that a stripped (no
 855     symbols) executable should be built.</dd>
 856     <dt><a name="RANLIB"><tt>RANLIB</tt></a><small>(defaulted)</small></dt>
 857     <dd>Specifies the path to the <tt>ranlib</tt> tool.</dd>
 858     <dt><a name="RM"><tt>RM</tt></a><small>(defaulted)</small></dt>
 859     <dd>Specifies the path to the <tt>rm</tt> tool.</dd>
 860     <dt><a name="SED"><tt>SED</tt></a><small>(defaulted)</small></dt>
 861     <dd>Specifies the path to the <tt>sed</tt> tool.</dd>
 862     <dt><a name="SHLIBEXT"><tt>SHLIBEXT</tt></a><small>(configured)</small></dt>
 863     <dd>Provides the filename extension to use for shared libraries.</dd>
 864     <dt><a name="TBLGEN"><tt>TBLGEN</tt></a><small>(defaulted)</small></dt>
 865     <dd>Specifies the path to the <tt>tblgen</tt> tool.</dd>
 866     <dt><a name="TAR"><tt>TAR</tt></a><small>(defaulted)</small></dt>
 867     <dd>Specifies the path to the <tt>tar</tt> tool.</dd>
 868     <dt><a name="ZIP"><tt>ZIP</tt></a><small>(defaulted)</small></dt>
 869     <dd>Specifies the path to the <tt>zip</tt> tool.</dd>
 870   </dl>
 871 </div>
 872
 873 <!-- ======================================================================= -->
 874 <div class="doc_subsection"><a name="getvars">Readable Variables</a></div>
 875 <div class="doc_text">
 876   <p>Variables listed in the table below can be used by the user's Makefile but
 877   should not be changed. Changing the value will generally cause the build to go
 878   wrong, so don't do it.</p>
 879   <dl>
 880     <dt><a name="bindir"><tt>bindir</tt></a></dt>
 881     <dd>The directory into which executables will ultimately be installed. This
 882     value is derived from the <tt>--prefix</tt> option given to
 883     <tt>configure</tt>.</dd>
 884     <dt><a name="BuildMode"><tt>BuildMode</tt></a></dt>
 885     <dd>The name of the type of build being performed: Debug, Release, or
 886     Profile</dd>
 887     <dt><a name="bytecode_libdir"><tt>bytecode_libdir</tt></a></dt>
 888     <dd>The directory into which bytecode libraries will ultimately be
 889     installed.  This value is derived from the <tt>--prefix</tt> option given to
 890     <tt>configure</tt>.</dd>
 891     <dt><a name="ConfigureScriptFLAGS"><tt>ConfigureScriptFLAGS</tt></a></dt>
 892     <dd>Additional flags given to the <tt>configure</tt> script when
 893     reconfiguring.</dd>
 894     <dt><a name="DistDir"><tt>DistDir</tt></a></dt>
 895     <dd>The <em>current</em> directory for which a distribution copy is being
 896     made.</dd>
 897     <dt><a name="Echo"><tt>Echo</tt></a></dt>
 898     <dd>The LLVM Makefile System output command. This provides the
 899     <tt>llvm[n]</tt> prefix and starts with @ so the command itself is not
 900     printed by <tt>make</tt>.</dd>
 901     <dt><a name="EchoCmd"><tt>EchoCmd</tt></a></dt>
 902     <dd> Same as <a href="#Echo"><tt>Echo</tt></a> but without the leading @.
 903     </dd>
 904     <dt><a name="includedir"><tt>includedir</tt></a></dt>
 905     <dd>The directory into which include files will ultimately be installed.
 906     This value is derived from the <tt>--prefix</tt> option given to
 907     <tt>configure</tt>.</dd>
 908     <dt><a name="libdir"><tt>libdir</tt></a></dt><dd></dd>
 909     <dd>The directory into which native libraries will ultimately be installed.
 910     This value is derived from the <tt>--prefix</tt> option given to
 911     <tt>configure</tt>.</dd>
 912     <dt><a name="LibDir"><tt>LibDir</tt></a></dt>
 913     <dd>The configuration specific directory into which libraries are placed
 914     before installation.</dd>
 915     <dt><a name="MakefileConfig"><tt>MakefileConfig</tt></a></dt>
 916     <dd>Full path of the <tt>Makefile.config</tt> file.</dd>
 917     <dt><a name="MakefileConfigIn"><tt>MakefileConfigIn</tt></a></dt>
 918     <dd>Full path of the <tt>Makefile.config.in</tt> file.</dd>
 919     <dt><a name="ObjDir"><tt>ObjDir</tt></a></dt>
 920     <dd>The configuration and directory specific directory where build objects
 921     (compilation results) are placed.</dd>
 922     <dt><a name="SubDirs"><tt>SubDirs</tt></a></dt>
 923     <dd>The complete list of sub-directories of the current directory as
 924     specified by other variables.</dd>
 925     <dt><a name="Sources"><tt>Sources</tt></a></dt>
 926     <dd>The complete list of source files.</dd>
 927     <dt><a name="sysconfdir"><tt>sysconfdir</tt></a></dt>
 928     <dd>The directory into which configuration files will ultimately be
 929     installed. This value is derived from the <tt>--prefix</tt> option given to
 930     <tt>configure</tt>.</dd>
 931     <dt><a name="ToolDir"><tt>ToolDir</tt></a></dt>
 932     <dd>The configuration specific directory into which executables are placed
 933     before they are installed.</dd>
 934     <dt><a name="TopDistDir"><tt>TopDistDir</tt></a></dt>
 935     <dd>The top most directory into which the distribution files are copied.
 936     </dd>
 937     <dt><a name="Verb"><tt>Verb</tt></a></dt>
 938     <dd>Use this as the first thing on your build script lines to enable or
 939     disable verbose mode. It expands to either an @ (quiet mode) or nothing
 940     (verbose mode). </dd>
 941   </dl>
 942 </div>
 943
 944 <!-- ======================================================================= -->
 945 <div class="doc_subsection"><a name="intvars">Internal Variables</a></div>
 946 <div class="doc_text">
 947   <p>Variables listed below are used by the LLVM Makefile System
 948   and considered internal. You should not use these variables under any
 949   circumstances.</p>
 950   <p><tt>
 951     Archive
 952     AR.Flags
 953     BaseNameSources
 954     BCCompile.C
 955     BCCompile.CXX
 956     BCLinkLib
 957     C.Flags
 958     Compile.C
 959     CompileCommonOpts
 960     Compile.CXX
 961     ConfigStatusScript
 962     ConfigureScript
 963     CPP.Flags
 964     CPP.Flags
 965     CXX.Flags
 966     DependFiles
 967     DestArchiveLib
 968     DestBytecodeLib
 969     DestModule
 970     DestRelinkedLib
 971     DestSharedLib
 972     DestTool
 973     DistAlways
 974     DistCheckDir
 975     DistCheckTop
 976     DistFiles
 977     DistName
 978     DistOther
 979     DistSources
 980     DistSubDirs
 981     DistTarBZ2
 982     DistTarGZip
 983     DistZip
 984     ExtraLibs
 985     FakeSources
 986     INCFiles
 987     InternalTargets
 988     LD.Flags
 989     LexFiles
 990     LexOutput
 991     LibName.A
 992     LibName.BC
 993     LibName.LA
 994     LibName.O
 995     LibTool.Flags
 996     Link
 997     LinkModule
 998     LLVMLibDir
 999     LLVMLibsOptions
1000     LLVMLibsPaths
1001     LLVMToolDir
1002     LLVMUsedLibs
1003     LocalTargets
1004     LTCompile.C
1005     LTCompile.CXX
1006     LTInstall
1007     Module
1008     ObjectsBC
1009     ObjectsLO
1010     ObjectsO
1011     ObjMakefiles
1012     ParallelTargets
1013     PreConditions
1014     ProjLibsOptions
1015     ProjLibsPaths
1016     ProjUsedLibs
1017     Ranlib
1018     RecursiveTargets
1019     Relink
1020     SrcMakefiles
1021     Strip
1022     StripWarnMsg
1023     TableGen
1024     TDFiles
1025     ToolBuildPath
1026     TopLevelTargets
1027     UserTargets
1028     YaccFiles
1029     YaccOutput
1030   </tt></p>
1031 </div>
1032
1033 <!-- *********************************************************************** -->
1034 <hr>
1035 <address>
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1040
1041   <a href="mailto:rspencer@x10sys.com">Reid Spencer</a><br>
1042   <a href="http://llvm.org">The LLVM Compiler Infrastructure</a><br>
1043   Last modified: $Date$
1044 </address>
1045 </body>
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