11 This document provides *usage* information about the LLVM makefile system. While
12 loosely patterned after the BSD makefile system, LLVM has taken a departure from
13 BSD in order to implement additional features needed by LLVM. Although makefile
14 systems, such as ``automake``, were attempted at one point, it has become clear
15 that the features needed by LLVM and the ``Makefile`` norm are too great to use
16 a more limited tool. Consequently, LLVM requires simply GNU Make 3.79, a widely
17 portable makefile processor. LLVM unabashedly makes heavy use of the features of
18 GNU Make so the dependency on GNU Make is firm. If you're not familiar with
19 ``make``, it is recommended that you read the `GNU Makefile Manual
20 <http://www.gnu.org/software/make/manual/make.html>`_.
22 While this document is rightly part of the `LLVM Programmer's
23 Manual <ProgrammersManual.html>`_, it is treated separately here because of the
24 volume of content and because it is often an early source of bewilderment for
30 The LLVM Makefile System is the component of LLVM that is responsible for
31 building the software, testing it, generating distributions, checking those
32 distributions, installing and uninstalling, etc. It consists of a several files
33 throughout the source tree. These files and other general concepts are described
39 The LLVM Makefile System is quite generous. It not only builds its own software,
40 but it can build yours too. Built into the system is knowledge of the
41 ``llvm/projects`` directory. Any directory under ``projects`` that has both a
42 ``configure`` script and a ``Makefile`` is assumed to be a project that uses the
43 LLVM Makefile system. Building software that uses LLVM does not require the
44 LLVM Makefile System nor even placement in the ``llvm/projects``
45 directory. However, doing so will allow your project to get up and running
46 quickly by utilizing the built-in features that are used to compile LLVM. LLVM
47 compiles itself using the same features of the makefile system as used for
50 For complete details on setting up your projects configuration, simply mimic the
51 ``llvm/projects/sample`` project. Or for further details, consult the
52 `Projects <Projects.html>`_ page.
57 To use the makefile system, you simply create a file named ``Makefile`` in your
58 directory and declare values for certain variables. The variables and values
59 that you select determine what the makefile system will do. These variables
60 enable rules and processing in the makefile system that automatically Do The
66 Setting variables alone is not enough. You must include into your Makefile
67 additional files that provide the rules of the LLVM Makefile system. The various
68 files involved are described in the sections that follow.
73 Each directory to participate in the build needs to have a file named
74 ``Makefile``. This is the file first read by ``make``. It has three
77 #. Settable Variables --- Required that must be set first.
78 #. ``include $(LEVEL)/Makefile.common`` --- include the LLVM Makefile system.
79 #. Override Variables --- Override variables set by the LLVM Makefile system.
81 .. _$(LEVEL)/Makefile.common:
86 Every project must have a ``Makefile.common`` file at its top source
87 directory. This file serves three purposes:
89 #. It includes the project's configuration makefile to obtain values determined
90 by the ``configure`` script. This is done by including the
91 `$(LEVEL)/Makefile.config`_ file.
93 #. It specifies any other (static) values that are needed throughout the
94 project. Only values that are used in all or a large proportion of the
95 project's directories should be placed here.
97 #. It includes the standard rules for the LLVM Makefile system,
98 `$(LLVM_SRC_ROOT)/Makefile.rules`_. This file is the *guts* of the LLVM
101 .. _$(LEVEL)/Makefile.config:
106 Every project must have a ``Makefile.config`` at the top of its *build*
107 directory. This file is **generated** by the ``configure`` script from the
108 pattern provided by the ``Makefile.config.in`` file located at the top of the
109 project's *source* directory. The contents of this file depend largely on what
110 configuration items the project uses, however most projects can get what they
111 need by just relying on LLVM's configuration found in
112 ``$(LLVM_OBJ_ROOT)/Makefile.config``.
114 .. _$(LLVM_SRC_ROOT)/Makefile.rules:
119 This file, located at ``$(LLVM_SRC_ROOT)/Makefile.rules`` is the heart of the
120 LLVM Makefile System. It provides all the logic, dependencies, and rules for
121 building the targets supported by the system. What it does largely depends on
122 the values of ``make`` `variables`_ that have been set *before*
123 ``Makefile.rules`` is included.
128 User ``Makefile``\s need not have comments in them unless the construction is
129 unusual or it does not strictly follow the rules and patterns of the LLVM
130 makefile system. Makefile comments are invoked with the pound (``#``) character.
131 The ``#`` character and any text following it, to the end of the line, are
137 This section provides some examples of the different kinds of modules you can
138 build with the LLVM makefile system. In general, each directory you provide will
139 build a single object although that object may be composed of additionally
145 Only a few variable definitions are needed to build a regular library.
146 Normally, the makefile system will build all the software into a single
147 ``libname.o`` (pre-linked) object. This means the library is not searchable and
148 that the distinction between compilation units has been dissolved. Optionally,
149 you can ask for a shared library (.so) or archive library (.a) built. Archive
150 libraries are the default. For example:
152 .. code-block:: makefile
158 says to build a library named ``mylib`` with both a shared library
159 (``mylib.so``) and an archive library (``mylib.a``) version. The contents of all
160 the libraries produced will be the same, they are just constructed differently.
161 Note that you normally do not need to specify the sources involved. The LLVM
162 Makefile system will infer the source files from the contents of the source
165 The ``LOADABLE_MODULE=1`` directive can be used in conjunction with
166 ``SHARED_LIBRARY=1`` to indicate that the resulting shared library should be
167 openable with the ``dlopen`` function and searchable with the ``dlsym`` function
168 (or your operating system's equivalents). While this isn't strictly necessary on
169 Linux and a few other platforms, it is required on systems like HP-UX and
170 Darwin. You should use ``LOADABLE_MODULE`` for any shared library that you
171 intend to be loaded into an tool via the ``-load`` option. `Pass documentation
172 <writing-an-llvm-pass-makefile>`_ has an example of why you might want to do
178 In some situations, you need to create a loadable module. Loadable modules can
179 be loaded into programs like ``opt`` or ``llc`` to specify additional passes to
180 run or targets to support. Loadable modules are also useful for debugging a
181 pass or providing a pass with another package if that pass can't be included in
184 LLVM provides complete support for building such a module. All you need to do is
185 use the ``LOADABLE_MODULE`` variable in your ``Makefile``. For example, to build
186 a loadable module named ``MyMod`` that uses the LLVM libraries ``LLVMSupport.a``
187 and ``LLVMSystem.a``, you would specify:
189 .. code-block:: makefile
193 LINK_COMPONENTS := support system
195 Use of the ``LOADABLE_MODULE`` facility implies several things:
197 #. There will be no "``lib``" prefix on the module. This differentiates it from
198 a standard shared library of the same name.
200 #. The `SHARED_LIBRARY`_ variable is turned on.
202 #. The `LINK_LIBS_IN_SHARED`_ variable is turned on.
204 A loadable module is loaded by LLVM via the facilities of libtool's libltdl
205 library which is part of ``lib/System`` implementation.
210 For building executable programs (tools), you must provide the name of the tool
211 and the names of the libraries you wish to link with the tool. For example:
213 .. code-block:: makefile
217 LINK_COMPONENTS = support system
219 says that we are to build a tool name ``mytool`` and that it requires three
220 libraries: ``mylib``, ``LLVMSupport.a`` and ``LLVMSystem.a``.
222 Note that two different variables are used to indicate which libraries are
223 linked: ``USEDLIBS`` and ``LLVMLIBS``. This distinction is necessary to support
224 projects. ``LLVMLIBS`` refers to the LLVM libraries found in the LLVM object
225 directory. ``USEDLIBS`` refers to the libraries built by your project. In the
226 case of building LLVM tools, ``USEDLIBS`` and ``LLVMLIBS`` can be used
227 interchangeably since the "project" is LLVM itself and ``USEDLIBS`` refers to
228 the same place as ``LLVMLIBS``.
230 Also note that there are two different ways of specifying a library: with a
231 ``.a`` suffix and without. Without the suffix, the entry refers to the re-linked
232 (.o) file which will include *all* symbols of the library. This is
233 useful, for example, to include all passes from a library of passes. If the
234 ``.a`` suffix is used then the library is linked as a searchable library (with
235 the ``-l`` option). In this case, only the symbols that are unresolved *at
236 that point* will be resolved from the library, if they exist. Other
237 (unreferenced) symbols will not be included when the ``.a`` syntax is used. Note
238 that in order to use the ``.a`` suffix, the library in question must have been
239 built with the ``ARCHIVE_LIBRARY`` option set.
244 Many tools will want to use the JIT features of LLVM. To do this, you simply
245 specify that you want an execution 'engine', and the makefiles will
246 automatically link in the appropriate JIT for the host or an interpreter if none
249 .. code-block:: makefile
251 TOOLNAME = my_jit_tool
253 LINK_COMPONENTS = engine
255 Of course, any additional libraries may be listed as other components. To get a
256 full understanding of how this changes the linker command, it is recommended
261 % cd examples/Fibonacci
267 This section describes each of the targets that can be built using the LLVM
268 Makefile system. Any target can be invoked from any directory but not all are
269 applicable to a given directory (e.g. "check", "dist" and "install" will always
270 operate as if invoked from the top level directory).
272 ================= =============== ==================
273 Target Name Implied Targets Target Description
274 ================= =============== ==================
275 ``all`` \ Compile the software recursively. Default target.
276 ``all-local`` \ Compile the software in the local directory only.
277 ``check`` \ Change to the ``test`` directory in a project and run the test suite there.
278 ``check-local`` \ Run a local test suite. Generally this is only defined in the ``Makefile`` of the project's ``test`` directory.
279 ``clean`` \ Remove built objects recursively.
280 ``clean-local`` \ Remove built objects from the local directory only.
281 ``dist`` ``all`` Prepare a source distribution tarball.
282 ``dist-check`` ``all`` Prepare a source distribution tarball and check that it builds.
283 ``dist-clean`` ``clean`` Clean source distribution tarball temporary files.
284 ``install`` ``all`` Copy built objects to installation directory.
285 ``preconditions`` ``all`` Check to make sure configuration and makefiles are up to date.
286 ``printvars`` ``all`` Prints variables defined by the makefile system (for debugging).
287 ``tags`` \ Make C and C++ tags files for emacs and vi.
288 ``uninstall`` \ Remove built objects from installation directory.
289 ================= =============== ==================
296 When you invoke ``make`` with no arguments, you are implicitly instructing it to
297 seek the ``all`` target (goal). This target is used for building the software
298 recursively and will do different things in different directories. For example,
299 in a ``lib`` directory, the ``all`` target will compile source files and
300 generate libraries. But, in a ``tools`` directory, it will link libraries and
301 generate executables.
306 This target is the same as `all`_ but it operates only on the current directory
307 instead of recursively.
312 This target can be invoked from anywhere within a project's directories but
313 always invokes the `check-local`_ target in the project's ``test`` directory, if
314 it exists and has a ``Makefile``. A warning is produced otherwise. If
315 `TESTSUITE`_ is defined on the ``make`` command line, it will be passed down to
316 the invocation of ``make check-local`` in the ``test`` directory. The intended
317 usage for this is to assist in running specific suites of tests. If
318 ``TESTSUITE`` is not set, the implementation of ``check-local`` should run all
319 normal tests. It is up to the project to define what different values for
320 ``TESTSUTE`` will do. See the :doc:`Testing Guide <TestingGuide>` for further
326 This target should be implemented by the ``Makefile`` in the project's ``test``
327 directory. It is invoked by the ``check`` target elsewhere. Each project is
328 free to define the actions of ``check-local`` as appropriate for that
329 project. The LLVM project itself uses the :doc:`Lit <CommandGuide/lit>` testing
330 tool to run a suite of feature and regression tests. Other projects may choose
331 to use :program:`lit` or any other testing mechanism.
336 This target cleans the build directory, recursively removing all things that the
337 Makefile builds. The cleaning rules have been made guarded so they shouldn't go
338 awry (via ``rm -f $(UNSET_VARIABLE)/*`` which will attempt to erase the entire
339 directory structure).
344 This target does the same thing as ``clean`` but only for the current (local)
350 This target builds a distribution tarball. It first builds the entire project
351 using the ``all`` target and then tars up the necessary files and compresses
352 it. The generated tarball is sufficient for a casual source distribution, but
353 probably not for a release (see ``dist-check``).
358 This target does the same thing as the ``dist`` target but also checks the
359 distribution tarball. The check is made by unpacking the tarball to a new
360 directory, configuring it, building it, installing it, and then verifying that
361 the installation results are correct (by comparing to the original build). This
362 target can take a long time to run but should be done before a release goes out
363 to make sure that the distributed tarball can actually be built into a working
369 This is a special form of the ``clean`` clean target. It performs a normal
370 ``clean`` but also removes things pertaining to building the distribution.
375 This target finalizes shared objects and executables and copies all libraries,
376 headers, executables and documentation to the directory given with the
377 ``--prefix`` option to ``configure``. When completed, the prefix directory will
378 have everything needed to **use** LLVM.
380 The LLVM makefiles can generate complete **internal** documentation for all the
381 classes by using ``doxygen``. By default, this feature is **not** enabled
382 because it takes a long time and generates a massive amount of data (>100MB). If
383 you want this feature, you must configure LLVM with the --enable-doxygen switch
384 and ensure that a modern version of doxygen (1.3.7 or later) is available in
385 your ``PATH``. You can download doxygen from `here
386 <http://www.stack.nl/~dimitri/doxygen/download.html#latestsrc>`_.
391 This utility target checks to see if the ``Makefile`` in the object directory is
392 older than the ``Makefile`` in the source directory and copies it if so. It also
393 reruns the ``configure`` script if that needs to be done and rebuilds the
394 ``Makefile.config`` file similarly. Users may overload this target to ensure
395 that sanity checks are run *before* any building of targets as all the targets
396 depend on ``preconditions``.
401 This utility target just causes the LLVM makefiles to print out some of the
402 makefile variables so that you can double check how things are set.
407 This utility target will force a reconfigure of LLVM or your project. It simply
408 runs ``$(PROJ_OBJ_ROOT)/config.status --recheck`` to rerun the configuration
409 tests and rebuild the configured files. This isn't generally useful as the
410 makefiles will reconfigure themselves whenever its necessary.
419 This utility target, only available when ``$(PROJ_OBJ_ROOT)`` is not the same as
420 ``$(PROJ_SRC_ROOT)``, will completely clean the ``$(PROJ_OBJ_ROOT)`` directory
421 by removing its content entirely and reconfiguring the directory. This returns
422 the ``$(PROJ_OBJ_ROOT)`` directory to a completely fresh state. All content in
423 the directory except configured files and top-level makefiles will be lost.
428 This target will generate a ``TAGS`` file in the top-level source directory. It
429 is meant for use with emacs, XEmacs, or ViM. The TAGS file provides an index of
430 symbol definitions so that the editor can jump you to the definition
436 This target is the opposite of the ``install`` target. It removes the header,
437 library and executable files from the installation directories. Note that the
438 directories themselves are not removed because it is not guaranteed that LLVM is
439 the only thing installing there (e.g. ``--prefix=/usr``).
446 Variables are used to tell the LLVM Makefile System what to do and to obtain
447 information from it. Variables are also used internally by the LLVM Makefile
448 System. Variable names that contain only the upper case alphabetic letters and
449 underscore are intended for use by the end user. All other variables are
450 internal to the LLVM Makefile System and should not be relied upon nor
451 modified. The sections below describe how to use the LLVM Makefile
457 Variables listed in the table below should be set *before* the inclusion of
458 `$(LEVEL)/Makefile.common`_. These variables provide input to the LLVM make
459 system that tell it what to do for the current directory.
462 If set to any value, causes an archive (.a) library to be built.
465 Specifies a set of source files that are generated from other source
466 files. These sources will be built before any other target processing to
467 ensure they are present.
470 Specifies a set of configuration files to be installed.
473 If set to any value, causes the build to include debugging symbols even in
474 optimized objects, libraries and executables. This alters the flags
475 specified to the compilers and linkers. Debugging isn't fun in an optimized
476 build, but it is possible.
479 Specifies a set of directories, usually children of the current directory,
480 that should also be made using the same goal. These directories will be
483 ``DISABLE_AUTO_DEPENDENCIES``
484 If set to any value, causes the makefiles to **not** automatically generate
485 dependencies when running the compiler. Use of this feature is discouraged
486 and it may be removed at a later date.
489 If set to 1, causes the build to generate optimized objects, libraries and
490 executables. This alters the flags specified to the compilers and
491 linkers. Generally debugging won't be a fun experience with an optimized
495 If set to 1, causes the build to generate both optimized and profiled
496 objects, libraries and executables. This alters the flags specified to the
497 compilers and linkers to ensure that profile data can be collected from the
498 tools built. Use the ``gprof`` tool to analyze the output from the profiled
499 tools (``gmon.out``).
501 ``DISABLE_ASSERTIONS``
502 If set to 1, causes the build to disable assertions, even if building a
503 debug or profile build. This will exclude all assertion check code from the
504 build. LLVM will execute faster, but with little help when things go
507 ``EXPERIMENTAL_DIRS``
508 Specify a set of directories that should be built, but if they fail, it
509 should not cause the build to fail. Note that this should only be used
510 temporarily while code is being written.
512 ``EXPORTED_SYMBOL_FILE``
513 Specifies the name of a single file that contains a list of the symbols to
514 be exported by the linker. One symbol per line.
516 ``EXPORTED_SYMBOL_LIST``
517 Specifies a set of symbols to be exported by the linker.
520 Specifies additional files that should be distributed with LLVM. All source
521 files, all built sources, all Makefiles, and most documentation files will
522 be automatically distributed. Use this variable to distribute any files that
523 are not automatically distributed.
526 If set to any value, specifies that when linking executables the makefiles
527 should retain debug symbols in the executable. Normally, symbols are
528 stripped from the executable.
531 Specify the level of nesting from the top level. This variable must be set
532 in each makefile as it is used to find the top level and thus the other
536 Specify the name of the library to be built. (Required For Libraries)
539 When specified for building a tool, the value of this variable will be
540 passed to the ``llvm-config`` tool to generate a link line for the
541 tool. Unlike ``USEDLIBS`` and ``LLVMLIBS``, not all libraries need to be
542 specified. The ``llvm-config`` tool will figure out the library dependencies
543 and add any libraries that are needed. The ``USEDLIBS`` variable can still
544 be used in conjunction with ``LINK_COMPONENTS`` so that additional
545 project-specific libraries can be linked with the LLVM libraries specified
546 by ``LINK_COMPONENTS``.
548 .. _LINK_LIBS_IN_SHARED:
550 ``LINK_LIBS_IN_SHARED``
551 By default, shared library linking will ignore any libraries specified with
552 the `LLVMLIBS`_ or `USEDLIBS`_. This prevents shared libs from including
553 things that will be in the LLVM tool the shared library will be loaded
554 into. However, sometimes it is useful to link certain libraries into your
555 shared library and this option enables that feature.
560 Specifies the set of libraries from the LLVM ``$(ObjDir)`` that will be
561 linked into the tool or library.
564 If set to any value, causes the shared library being built to also be a
565 loadable module. Loadable modules can be opened with the dlopen() function
566 and searched with dlsym (or the operating system's equivalent). Note that
567 setting this variable without also setting ``SHARED_LIBRARY`` will have no
571 Specifies that the build products of the directory should not be installed
572 but should be built even if the ``install`` target is given. This is handy
573 for directories that build libraries or tools that are only used as part of
574 the build process, such as code generators (e.g. ``tblgen``).
577 Specify a set of directories that may be built, if they exist, but it is
578 not an error for them not to exist.
581 Specify a set of directories to build recursively and in parallel if the
582 ``-j`` option was used with ``make``.
587 If set to any value, causes a shared library (``.so``) to be built in
588 addition to any other kinds of libraries. Note that this option will cause
589 all source files to be built twice: once with options for position
590 independent code and once without. Use it only where you really need a
593 ``SOURCES`` (optional)
594 Specifies the list of source files in the current directory to be
595 built. Source files of any type may be specified (programs, documentation,
596 config files, etc.). If not specified, the makefile system will infer the
597 set of source files from the files present in the current directory.
600 Specifies a set of filename suffixes that occur in suffix match rules. Only
601 set this if your local ``Makefile`` specifies additional suffix match
605 Specifies the name of the LLVM code generation target that the current
606 directory builds. Setting this variable enables additional rules to build
607 ``.inc`` files from ``.td`` files.
612 Specifies the directory of tests to run in ``llvm/test``.
615 Specifies the name of the tool that the current directory should build.
618 Implies ``VERBOSE`` and also tells each tool invoked to be verbose. This is
619 handy when you're trying to see the sub-tools invoked by each tool invoked
620 by the makefile. For example, this will pass ``-v`` to the GCC compilers
621 which causes it to print out the command lines it uses to invoke sub-tools
622 (compiler, assembler, linker).
627 Specifies the list of project libraries that will be linked into the tool or
631 Tells the Makefile system to produce detailed output of what it is doing
632 instead of just summary comments. This will generate a LOT of output.
637 Override variables can be used to override the default values provided by the
638 LLVM makefile system. These variables can be set in several ways:
640 * In the environment (e.g. setenv, export) --- not recommended.
641 * On the ``make`` command line --- recommended.
642 * On the ``configure`` command line.
643 * In the Makefile (only *after* the inclusion of `$(LEVEL)/Makefile.common`_).
645 The override variables are given below:
648 Specifies the path to the ``ar`` tool.
651 The directory into which the products of build rules will be placed. This
652 might be the same as `PROJ_SRC_DIR`_ but typically is not.
657 The directory which contains the source files to be built.
660 If set to 1, build examples in ``examples`` and (if building Clang)
661 ``tools/clang/examples`` directories.
663 ``BZIP2`` (configured)
664 The path to the ``bzip2`` tool.
667 The path to the 'C' compiler.
670 Additional flags to be passed to the 'C' compiler.
673 Additional flags passed to the C/C++ preprocessor.
676 Specifies the path to the C++ compiler.
679 Additional flags to be passed to the C++ compiler.
681 ``DATE`` (configured)
682 Specifies the path to the ``date`` program or any program that can generate
683 the current date and time on its standard output.
686 Specifies the path to the ``dot`` tool or ``false`` if there isn't one.
688 ``ECHO`` (configured)
689 Specifies the path to the ``echo`` tool for printing output.
691 ``EXEEXT`` (configured)
692 Provides the extension to be used on executables built by the makefiles.
693 The value may be empty on platforms that do not use file extensions for
694 executables (e.g. Unix).
696 ``INSTALL`` (configured)
697 Specifies the path to the ``install`` tool.
699 ``LDFLAGS`` (configured)
700 Allows users to specify additional flags to pass to the linker.
702 ``LIBS`` (configured)
703 The list of libraries that should be linked with each tool.
705 ``LIBTOOL`` (configured)
706 Specifies the path to the ``libtool`` tool. This tool is renamed ``mklib``
707 by the ``configure`` script.
709 ``LLVMAS`` (defaulted)
710 Specifies the path to the ``llvm-as`` tool.
712 ``LLVMGCC`` (defaulted)
713 Specifies the path to the LLVM version of the GCC 'C' Compiler.
715 ``LLVMGXX`` (defaulted)
716 Specifies the path to the LLVM version of the GCC C++ Compiler.
718 ``LLVMLD`` (defaulted)
719 Specifies the path to the LLVM bitcode linker tool
721 ``LLVM_OBJ_ROOT`` (configured)
722 Specifies the top directory into which the output of the build is placed.
724 ``LLVM_SRC_ROOT`` (configured)
725 Specifies the top directory in which the sources are found.
727 ``LLVM_TARBALL_NAME`` (configured)
728 Specifies the name of the distribution tarball to create. This is configured
729 from the name of the project and its version number.
731 ``MKDIR`` (defaulted)
732 Specifies the path to the ``mkdir`` tool that creates directories.
735 If set, specifies the list of tools to build.
737 ``PLATFORMSTRIPOPTS``
738 The options to provide to the linker to specify that a stripped (no symbols)
739 executable should be built.
741 ``RANLIB`` (defaulted)
742 Specifies the path to the ``ranlib`` tool.
745 Specifies the path to the ``rm`` tool.
748 Specifies the path to the ``sed`` tool.
750 ``SHLIBEXT`` (configured)
751 Provides the filename extension to use for shared libraries.
753 ``TBLGEN`` (defaulted)
754 Specifies the path to the ``tblgen`` tool.
757 Specifies the path to the ``tar`` tool.
760 Specifies the path to the ``zip`` tool.
765 Variables listed in the table below can be used by the user's Makefile but
766 should not be changed. Changing the value will generally cause the build to go
767 wrong, so don't do it.
770 The directory into which executables will ultimately be installed. This
771 value is derived from the ``--prefix`` option given to ``configure``.
774 The name of the type of build being performed: Debug, Release, or
778 The directory into which bitcode libraries will ultimately be installed.
779 This value is derived from the ``--prefix`` option given to ``configure``.
781 ``ConfigureScriptFLAGS``
782 Additional flags given to the ``configure`` script when reconfiguring.
785 The *current* directory for which a distribution copy is being made.
790 The LLVM Makefile System output command. This provides the ``llvm[n]``
791 prefix and starts with ``@`` so the command itself is not printed by
795 Same as `Echo`_ but without the leading ``@``.
798 The directory into which include files will ultimately be installed. This
799 value is derived from the ``--prefix`` option given to ``configure``.
802 The directory into which native libraries will ultimately be installed.
803 This value is derived from the ``--prefix`` option given to
807 The configuration specific directory into which libraries are placed before
811 Full path of the ``Makefile.config`` file.
814 Full path of the ``Makefile.config.in`` file.
817 The configuration and directory specific directory where build objects
818 (compilation results) are placed.
821 The complete list of sub-directories of the current directory as
822 specified by other variables.
825 The complete list of source files.
828 The directory into which configuration files will ultimately be
829 installed. This value is derived from the ``--prefix`` option given to
833 The configuration specific directory into which executables are placed
834 before they are installed.
837 The top most directory into which the distribution files are copied.
840 Use this as the first thing on your build script lines to enable or disable
841 verbose mode. It expands to either an ``@`` (quiet mode) or nothing (verbose
847 Variables listed below are used by the LLVM Makefile System and considered
848 internal. You should not use these variables under any circumstances.
850 .. code-block:: makefile