- Libraries @@ -77,10 +77,10 @@ - +
- The LINK_LIBS_IN_SHARED variable is turned on. -
- The DONT_BUILD_RELINKED variable - is turned on.
- BYTECODE_LIBRARY -
- If set to any value, causes a bytecode library (.bc) to be built. +
- If set to any value, causes a bitcode library (.bc) to be built.
- CONFIG_FILES
- Specifies a set of configuration files to be installed. +
- DEBUG_SYMBOLS +
- If set to any value, causes the build to include debugging + symbols even in optimized objects, libraries and executables. This + alters the flags specified to the compilers and linkers. Debugging + isn't fun in an optimized build, but it is possible.
- DIRS
- Specifies a set of directories, usually children of the current
directory, that should also be made using the same goal. These directories
@@ -637,25 +642,20 @@
- If set to any value, causes the makefiles to not automatically generate dependencies when running the compiler. Use of this feature is discouraged and it may be removed at a later date.
- - DONT_BUILD_RELINKED -
- If set to any value, causes a relinked library (.o) not to be built. By - default, libraries are built as re-linked since most LLVM libraries are - needed in their entirety and re-linked libraries will be linked more quickly - than equivalent archive libraries.
- ENABLE_OPTIMIZED -
- If set to any value, causes the build to generate optimized objects,
+
- If set to 1, causes the build to generate optimized objects, libraries and executables. This alters the flags specified to the compilers and linkers. Generally debugging won't be a fun experience with an optimized build.
- ENABLE_PROFILING -
- If set to any value, causes the build to generate both optimized and
+
- If set to 1, causes the build to generate both optimized and profiled objects, libraries and executables. This alters the flags specified to the compilers and linkers to ensure that profile data can be collected from the tools built. Use the gprof tool to analyze the output from the profiled tools (gmon.out).
- DISABLE_ASSERTIONS -
- If set to any value, causes the build to disable assertions, even if
- building a release or profile build. This will exclude all assertion check
+
- If set to 1, causes the build to disable assertions, even if + building a debug or profile build. This will exclude all assertion check code from the build. LLVM will execute faster, but with little help when things go wrong.
- EXPERIMENTAL_DIRS @@ -683,6 +683,15 @@
- LIBRARYNAME
- Specify the name of the library to be built. (Required For Libraries) +
- LINK_COMPONENTS +
- When specified for building a tool, the value of this variable will be + passed to the llvm-config tool to generate a link line for the + tool. Unlike USEDLIBS and LLVMLIBS, not all libraries need + to be specified. The llvm-config tool will figure out the library + dependencies and add any libraries that are needed. The USEDLIBS + variable can still be used in conjunction with LINK_COMPONENTS so + that additional project-specific libraries can be linked with the LLVM + libraries specified by LINK_COMPONENTS
- LINK_LIBS_IN_SHARED
- By default, shared library linking will ignore any libraries specified with the LLVMLIBS or USEDLIBS. @@ -700,10 +709,16 @@ setting this variable without also setting SHARED_LIBRARY will have no effect.
- MODULE_NAME -
- Specifies the name of a bytecode module to be created. A bytecode
+
- Specifies the name of a bitcode module to be created. A bitcode module can be specified in conjunction with other kinds of library builds - or by itself. It constructs from the sources a single linked bytecode + or by itself. It constructs from the sources a single linked bitcode file.
+ - NO_INSTALL +
- Specifies that the build products of the directory should not be + installed but should be built even if the install target is given. + This is handy for directories that build libraries or tools that are only + used as part of the build process, such as code generators (e.g. + tblgen).
- OPTIONAL_DIRS
- Specify a set of directories that may be built, if they exist, but its not an error for them not to exist. @@ -750,8 +765,8 @@
- AR (defaulted)
- Specifies the path to the ar tool. -
- BISON(configured) -
- Specifies the path to the bison tool.
- PROJ_OBJ_DIR
- The directory into which the products of build rules will be placed. This might be the same as @@ -775,6 +788,9 @@ not.
- PROJ_SRC_DIR
- The directory which contains the source files to be built. +
- BUILD_EXAMPLES +
- If set to 1, build examples in examples and (if building + Clang) tools/clang/examples directories.
- BZIP2(configured)
- The path to the bzip2 tool.
- CC(configured) @@ -793,19 +809,10 @@ isn't one.
- ECHO(configured)
- Specifies the path to the echo tool for printing output. -
- ETAGS(configured) -
- Specifies the path to the etags tool. -
- ETAGSFLAGS(configured) - -
- Provides flags to be passed to the etags tool.
- EXEEXT(configured)
- Provides the extension to be used on executables built by the makefiles. The value may be empty on platforms that do not use file extensions for executables (e.g. Unix). -
- FLEX(configured) -
- Specifies the path to the flex tool. -
- GCCLD(defaulted) -
- Specifies the path to the gccld tool.
- INSTALL(configured)
- Specifies the path to the install tool.
- LDFLAGS(configured) @@ -817,10 +824,16 @@ mklib by the configure script and always located in the
- LLVMAS(defaulted)
- Specifies the path to the llvm-as tool. +
- LLVMCC +
- Specifies the path to the LLVM capable compiler. +
- LLVMCXX +
- Specifies the path to the LLVM C++ capable compiler.
- LLVMGCC(defaulted)
- Specifies the path to the LLVM version of the GCC 'C' Compiler
- LLVMGXX(defaulted)
- Specifies the path to the LLVM version of the GCC C++ Compiler +
- LLVMLD(defaulted) +
- Specifies the path to the LLVM bitcode linker tool
- LLVM_OBJ_ROOT(configured)
- Specifies the top directory into which the output of the build is @@ -835,6 +848,8 @@
- MKDIR(defaulted)
- Specifies the path to the mkdir tool that creates directories. +
- ONLY_TOOLS +
- If set, specifies the list of tools to build.
- PLATFORMSTRIPOPTS
- The options to provide to the linker to specify that a stripped (no symbols) executable should be built. @@ -856,8 +871,8 @@
- BuildMode
- The name of the type of build being performed: Debug, Release, or Profile -
- bytecode_libdir -
- The directory into which bytecode libraries will ultimately be +
- bytecode_libdir +
- The directory into which bitcode libraries will ultimately be installed. This value is derived from the --prefix option given to configure.
- ConfigureScriptFLAGS @@ -927,8 +942,8 @@
Introduction
-This document provides usage information about the LLVM makefile system. While loosely patterned after the BSD makefile system, LLVM has taken a departure from BSD in order to implement additional features needed by LLVM. @@ -99,20 +99,19 @@
General Concepts
-The LLVM Makefile System is the component of LLVM that is responsible for building the software, testing it, generating distributions, checking those distributions, installing and uninstalling, etc. It consists of a several files throughout the source tree. These files and other general concepts are described in this section.
-Projects
+The LLVM Makefile System is quite generous. It not only builds its own software, but it can build yours too. Built into the system is knowledge of the llvm/projects directory. Any directory under projects @@ -129,8 +128,8 @@
Variable Values
+To use the makefile system, you simply create a file named Makefile in your directory and declare values for certain variables. The variables and values that you select determine what the makefile system @@ -139,16 +138,15 @@
Including Makefiles
+Setting variables alone is not enough. You must include into your Makefile additional files that provide the rules of the LLVM Makefile system. The various files involved are described in the sections that follow.
-Makefile
+Each directory to participate in the build needs to have a file named Makefile. This is the file first read by make. It has three sections:
@@ -163,9 +161,8 @@Makefile.common
+Every project must have a Makefile.common file at its top source directory. This file serves three purposes:
-
@@ -182,9 +179,8 @@
Makefile.config
+Every project must have a Makefile.config at the top of its build directory. This file is generated by the configure script from the pattern provided by the @@ -196,8 +192,8 @@
Makefile.rules
+This file, located at $(LLVM_SRC_ROOT)/Makefile.rules is the heart of the LLVM Makefile System. It provides all the logic, dependencies, and rules for building the targets supported by the system. What it does largely @@ -205,9 +201,11 @@ have been set before Makefile.rules is included.
Comments
+User Makefiles need not have comments in them unless the construction is unusual or it does not strictly follow the rules and patterns of the LLVM makefile system. Makefile comments are invoked with the pound (#) character. @@ -215,34 +213,34 @@ by make.
Tutorial
-This section provides some examples of the different kinds of modules you can build with the LLVM makefile system. In general, each directory you provide will build a single object although that object may be composed of additionally compiled components.
-Libraries
+Only a few variable definitions are needed to build a regular library. Normally, the makefile system will build all the software into a single libname.o (pre-linked) object. This means the library is not searchable and that the distinction between compilation units has been - dissolved. Optionally, you can ask for a shared library (.so), archive library - (.a) or to not have the default (relinked) library built. For example:
+ dissolved. Optionally, you can ask for a shared library (.so) or archive + library (.a) built. Archive libraries are the default. For example:
LIBRARYNAME = mylib
SHARED_LIBRARY = 1
ARCHIVE_LIBRARY = 1
- DONT_BUILD_RELINKED = 1
says to build a library named "mylib" with both a shared library - (mylib.so) and an archive library (mylib.a) version but - not to build the relinked object (mylib.o). The contents of all the + (mylib.so) and an archive library (mylib.a) version. The + contents of all the libraries produced will be the same, they are just constructed differently. Note that you normally do not need to specify the sources involved. The LLVM Makefile system will infer the source files from the contents of the source @@ -257,14 +255,13 @@ -load option. See the WritingAnLLVMPass.html document for an example of why you might want to do this. -
In some situations, it is desireable to build a single bytecode module from - a variety of sources, instead of an archive, shared library, or bytecode - library. Bytecode modules can be specified in addition to any of the other +
Bitcode Modules
+In some situations, it is desirable to build a single bitcode module from + a variety of sources, instead of an archive, shared library, or bitcode + library. Bitcode modules can be specified in addition to any of the other types of libraries by defining the MODULE_NAME variable. For example:
@@ -273,18 +270,18 @@
MODULE_NAME = mymod
will build a module named mymod.bc from the sources in the - directory. This module will be an aggregation of all the bytecode modules - derived from the sources. The example will also build a bytecode archive - containing a bytecode module for each compiled source file. The difference is + directory. This module will be an aggregation of all the bitcode modules + derived from the sources. The example will also build a bitcode archive + containing a bitcode module for each compiled source file. The difference is subtle, but important depending on how the module or library is to be linked.
Loadable Modules -
In some situations, you need to create a loadable module. Loadable modules can be loaded into programs like opt or llc to specify additional passes to run or targets to support. Loadable modules are also @@ -307,16 +304,16 @@ on.
A loadable module is loaded by LLVM via the facilities of libtool's libltdl library which is part of lib/System implementation.
Tools
+For building executable programs (tools), you must provide the name of the tool and the names of the libraries you wish to link with the tool. For example:
@@ -347,11 +344,10 @@ syntax is used. Note that in order to use the .a suffix, the library in question must have been built with the ARCHIVE_LIBRARY option set. -JIT Tools
+Many tools will want to use the JIT features of LLVM. To do this, you simply specify that you want an execution 'engine', and the makefiles will automatically link in the appropriate JIT for the host or an interpreter @@ -370,11 +366,15 @@
Targets Supported
-This section describes each of the targets that can be built using the LLVM Makefile system. Any target can be invoked from any directory but not all are applicable to a given directory (e.g. "check", "dist" and "install" will @@ -429,11 +429,10 @@
all (default)
+When you invoke make with no arguments, you are implicitly instructing it to seek the "all" target (goal). This target is used for building the software recursively and will do different things in different @@ -443,15 +442,15 @@
all-local
+This target is the same as all but it operates only on the current directory instead of recursively.
check
+This target can be invoked from anywhere within a project's directories but always invokes the check-local target in the project's test directory, if it exists and has a @@ -467,8 +466,8 @@
check-local
+This target should be implemented by the Makefile in the project's test directory. It is invoked by the check target elsewhere. Each project is free to define the actions of check-local as @@ -478,8 +477,8 @@
clean
+This target cleans the build directory, recursively removing all things that the Makefile builds. The cleaning rules have been made guarded so they shouldn't go awry (via rm -f $(UNSET_VARIABLE)/* which will attempt @@ -487,15 +486,15 @@
clean-local
+This target does the same thing as clean but only for the current (local) directory.
dist
+This target builds a distribution tarball. It first builds the entire project using the all target and then tars up the necessary files and compresses it. The generated tarball is sufficient for a casual source @@ -503,8 +502,8 @@
dist-check
+This target does the same thing as the dist target but also checks the distribution tarball. The check is made by unpacking the tarball to a new directory, configuring it, building it, installing it, and then verifying that @@ -515,16 +514,16 @@
dist-clean
+This is a special form of the clean clean target. It performs a normal clean but also removes things pertaining to building the distribution.
install
+This target finalizes shared objects and executables and copies all libraries, headers, executables and documentation to the directory given with the --prefix option to configure. When completed, @@ -541,8 +540,8 @@
preconditions
+This utility target checks to see if the Makefile in the object directory is older than the Makefile in the source directory and copies it if so. It also reruns the configure script if that needs to @@ -552,15 +551,15 @@
printvars
+This utility target just causes the LLVM makefiles to print out some of the makefile variables so that you can double check how things are set.
reconfigure
+This utility target will force a reconfigure of LLVM or your project. It simply runs $(PROJ_OBJ_ROOT)/config.status --recheck to rerun the configuration tests and rebuild the configured files. This isn't generally @@ -569,8 +568,8 @@
spotless
+This utility target, only available when $(PROJ_OBJ_ROOT) is not the same as $(PROJ_SRC_ROOT), will completely clean the $(PROJ_OBJ_ROOT) directory by removing its content entirely and @@ -581,8 +580,8 @@
tags
+This target will generate a TAGS file in the top-level source directory. It is meant for use with emacs, XEmacs, or ViM. The TAGS file provides an index of symbol definitions so that the editor can jump you to the @@ -590,18 +589,20 @@
uninstall
+This target is the opposite of the install target. It removes the header, library and executable files from the installation directories. Note that the directories themselves are not removed because it is not guaranteed that LLVM is the only thing installing there (e.g. --prefix=/usr).
Variables
-Variables are used to tell the LLVM Makefile System what to do and to obtain information from it. Variables are also used internally by the LLVM Makefile System. Variable names that contain only the upper case alphabetic @@ -609,11 +610,10 @@ variables are internal to the LLVM Makefile System and should not be relied upon nor modified. The sections below describe how to use the LLVM Makefile variables.
-Control Variables
+Variables listed in the table below should be set before the inclusion of $(LEVEL)/Makefile.common. These variables provide input to the LLVM make system that tell it what to do @@ -626,9 +626,14 @@ files. These sources will be built before any other target processing to ensure they are present.
Override Variables
+Override variables can be used to override the default values provided by the LLVM makefile system. These variables can be set in several ways:
@@ -766,8 +781,6 @@Readable Variables
+Variables listed in the table below can be used by the user's Makefile but should not be changed. Changing the value will generally cause the build to go wrong, so don't do it.
@@ -869,8 +884,8 @@Internal Variables
+Variables listed below are used by the LLVM Makefile System and considered internal. You should not use these variables under any circumstances.
@@ -950,9 +965,8 @@ CXX.Flags DependFiles DestArchiveLib - DestBytecodeLib + DestBitcodeLib DestModule - DestRelinkedLib DestSharedLib DestTool DistAlways @@ -971,8 +985,6 @@ INCFiles InternalTargets LD.Flags - LexFiles - LexOutput LibName.A LibName.BC LibName.LA @@ -986,9 +998,6 @@ LLVMToolDir LLVMUsedLibs LocalTargets - LTCompile.C - LTCompile.CXX - LTInstall Module ObjectsBC ObjectsLO @@ -1001,7 +1010,6 @@ ProjUsedLibs Ranlib RecursiveTargets - Relink SrcMakefiles Strip StripWarnMsg @@ -1010,21 +1018,21 @@ ToolBuildPath TopLevelTargets UserTargets - YaccFiles - YaccOutput
+ src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS">
- The LLVM Compiler Infrastructure
+ The LLVM Compiler Infrastructure
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