INSTALL - git - Git at Google


 		Git installation

 Normally you can just do "make" followed by "make install", and that
 will install the git programs in your own ~/bin/ directory.  If you want
 to do a global install, you can do

 	$ make prefix=/usr all doc info ;# as yourself
 	# make prefix=/usr install install-doc install-html install-info ;# as root

 (or prefix=/usr/local, of course).  Just like any program suite
 that uses $prefix, the built results have some paths encoded,
 which are derived from $prefix, so "make all; make prefix=/usr
 install" would not work.

 The beginning of the Makefile documents many variables that affect the way
 git is built.  You can override them either from the command line, or in a
 config.mak file.

 Alternatively you can use autoconf generated ./configure script to
 set up install paths (via config.mak.autogen), so you can write instead

 	$ make configure ;# as yourself
 	$ ./configure --prefix=/usr ;# as yourself
 	$ make all doc ;# as yourself
 	# make install install-doc install-html;# as root

 If you're willing to trade off (much) longer build time for a later
 faster git you can also do a profile feedback build with

 	$ make prefix=/usr profile
 	# make prefix=/usr PROFILE=BUILD install

 This will run the complete test suite as training workload and then
 rebuild git with the generated profile feedback. This results in a git
 which is a few percent faster on CPU intensive workloads.  This
 may be a good tradeoff for distribution packagers.

 Alternatively you can run profile feedback only with the git benchmark
 suite. This runs significantly faster than the full test suite, but
 has less coverage:

 	$ make prefix=/usr profile-fast
 	# make prefix=/usr PROFILE=BUILD install

 Or if you just want to install a profile-optimized version of git into
 your home directory, you could run:

 	$ make profile-install

 or
 	$ make profile-fast-install

 As a caveat: a profile-optimized build takes a *lot* longer since the
 git tree must be built twice, and in order for the profiling
 measurements to work properly, ccache must be disabled and the test
 suite has to be run using only a single CPU.  In addition, the profile
 feedback build stage currently generates a lot of additional compiler
 warnings.

 Issues of note:

  - Ancient versions of GNU Interactive Tools (pre-4.9.2) installed a
    program "git", whose name conflicts with this program.  But with
    version 4.9.2, after long hiatus without active maintenance (since
    around 1997), it changed its name to gnuit and the name conflict is no
    longer a problem.

    NOTE: When compiled with backward compatibility option, the GNU
    Interactive Tools package still can install "git", but you can build it
    with --disable-transition option to avoid this.

  - You can use git after building but without installing if you want
    to test drive it.  Simply run git found in bin-wrappers directory
    in the build directory, or prepend that directory to your $PATH.
    This however is less efficient than running an installed git, as
    you always need an extra fork+exec to run any git subcommand.

    It is still possible to use git without installing by setting a few
    environment variables, which was the way this was done
    traditionally.  But using git found in bin-wrappers directory in
    the build directory is far simpler.  As a historical reference, the
    old way went like this:

 	GIT_EXEC_PATH=`pwd`
 	PATH=`pwd`:$PATH
 	GITPERLLIB=`pwd`/perl/build/lib
 	export GIT_EXEC_PATH PATH GITPERLLIB

  - By default (unless NO_PERL is provided) Git will ship various perl
    scripts. However, for simplicity it doesn't use the
    ExtUtils::MakeMaker toolchain to decide where to place the perl
    libraries. Depending on the system this can result in the perl
    libraries not being where you'd like them if they're expected to be
    used by things other than Git itself.

    Manually supplying a perllibdir prefix should fix this, if this is
    a problem you care about, e.g.:

        prefix=/usr perllibdir=/usr/$(/usr/bin/perl -MConfig -wle 'print substr $Config{installsitelib}, 1 + length $Config{siteprefixexp}')

    Will result in e.g. perllibdir=/usr/share/perl/5.26.1 on Debian,
    perllibdir=/usr/share/perl5 (which we'd use by default) on CentOS.

  - Unless NO_PERL is provided Git will ship various perl libraries it
    needs. Distributors of Git will usually want to set
    NO_PERL_CPAN_FALLBACKS if NO_PERL is not provided to use their own
    copies of the CPAN modules Git needs.

  - Git is reasonably self-sufficient, but does depend on a few external
    programs and libraries.  Git can be used without most of them by adding
    the approriate "NO_<LIBRARY>=YesPlease" to the make command line or
    config.mak file.

 	- "zlib", the compression library. Git won't build without it.

 	- "ssh" is used to push and pull over the net.

 	- A POSIX-compliant shell is required to run many scripts needed
 	  for everyday use (e.g. "bisect", "pull").

 	- "Perl" version 5.8 or later is needed to use some of the
 	  features (e.g. preparing a partial commit using "git add -i/-p",
 	  interacting with svn repositories with "git svn").  If you can
 	  live without these, use NO_PERL.  Note that recent releases of
 	  Redhat/Fedora are reported to ship Perl binary package with some
 	  core modules stripped away (see http://lwn.net/Articles/477234/),
 	  so you might need to install additional packages other than Perl
 	  itself, e.g. Digest::MD5, File::Spec, File::Temp, Net::Domain,
 	  Net::SMTP, and Time::HiRes.

 	- git-imap-send needs the OpenSSL library to talk IMAP over SSL if
 	  you are using libcurl older than 7.34.0.  Otherwise you can use
 	  NO_OPENSSL without losing git-imap-send.

 	  By default, git uses OpenSSL for SHA1 but it will use its own
 	  library (inspired by Mozilla's) with either NO_OPENSSL or
 	  BLK_SHA1.  Also included is a version optimized for PowerPC
 	  (PPC_SHA1).

 	- "libcurl" library is used by git-http-fetch, git-fetch, and, if
 	  the curl version >= 7.34.0, for git-imap-send.  You might also
 	  want the "curl" executable for debugging purposes. If you do not
 	  use http:// or https:// repositories, and do not want to put
 	  patches into an IMAP mailbox, you do not have to have them
 	  (use NO_CURL).

 	- "expat" library; git-http-push uses it for remote lock
 	  management over DAV.  Similar to "curl" above, this is optional
 	  (with NO_EXPAT).

 	- "wish", the Tcl/Tk windowing shell is used in gitk to show the
 	  history graphically, and in git-gui.  If you don't want gitk or
 	  git-gui, you can use NO_TCLTK.

 	- A gettext library is used by default for localizing Git. The
 	  primary target is GNU libintl, but the Solaris gettext
 	  implementation also works.

 	  We need a gettext.h on the system for C code, gettext.sh (or
 	  Solaris gettext(1)) for shell scripts, and libintl-perl for Perl
 	  programs.

 	  Set NO_GETTEXT to disable localization support and make Git only
 	  use English. Under autoconf the configure script will do this
 	  automatically if it can't find libintl on the system.

 	- Python version 2.4 or later (but not 3.x, which is not
 	  supported by Perforce) is needed to use the git-p4 interface
 	  to Perforce.

  - Some platform specific issues are dealt with Makefile rules,
    but depending on your specific installation, you may not
    have all the libraries/tools needed, or you may have
    necessary libraries at unusual locations.  Please look at the
    top of the Makefile to see what can be adjusted for your needs.
    You can place local settings in config.mak and the Makefile
    will include them.  Note that config.mak is not distributed;
    the name is reserved for local settings.

  - To build and install documentation suite, you need to have
    the asciidoc/xmlto toolchain.  Because not many people are
    inclined to install the tools, the default build target
    ("make all") does _not_ build them.

    "make doc" builds documentation in man and html formats; there are
    also "make man", "make html" and "make info". Note that "make html"
    requires asciidoc, but not xmlto. "make man" (and thus make doc)
    requires both.

    "make install-doc" installs documentation in man format only; there
    are also "make install-man", "make install-html" and "make
    install-info".

    Building and installing the info file additionally requires
    makeinfo and docbook2X.  Version 0.8.3 is known to work.

    Building and installing the pdf file additionally requires
    dblatex.  Version >= 0.2.7 is known to work.

    All formats require at least asciidoc 8.4.1.

    There are also "make quick-install-doc", "make quick-install-man"
    and "make quick-install-html" which install preformatted man pages
    and html documentation. To use these build targets, you need to
    clone two separate git-htmldocs and git-manpages repositories next
    to the clone of git itself.

    It has been reported that docbook-xsl version 1.72 and 1.73 are
    buggy; 1.72 misformats manual pages for callouts, and 1.73 needs
    the patch in contrib/patches/docbook-xsl-manpages-charmap.patch

    Users attempting to build the documentation on Cygwin may need to ensure
    that the /etc/xml/catalog file looks something like this:

    <?xml version="1.0"?>
    <!DOCTYPE catalog PUBLIC
       "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
       "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"
    >
    <catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
      <rewriteURI
        uriStartString = "http://docbook.sourceforge.net/release/xsl/current"
        rewritePrefix = "/usr/share/sgml/docbook/xsl-stylesheets"
      />
      <rewriteURI
        uriStartString="http://www.oasis-open.org/docbook/xml/4.5"
        rewritePrefix="/usr/share/sgml/docbook/xml-dtd-4.5"
      />
   </catalog>

   This can be achieved with the following two xmlcatalog commands:

   xmlcatalog --noout \
      --add rewriteURI \
         http://docbook.sourceforge.net/release/xsl/current \
         /usr/share/sgml/docbook/xsl-stylesheets \
      /etc/xml/catalog

   xmlcatalog --noout \
      --add rewriteURI \
          http://www.oasis-open.org/docbook/xml/4.5/xsl/current \
          /usr/share/sgml/docbook/xml-dtd-4.5 \
      /etc/xml/catalog

	Git installation

	Normally you can just do "make" followed by "make install", and that
	will install the git programs in your own ~/bin/ directory. If you want
	to do a global install, you can do

	$ make prefix=/usr all doc info ;# as yourself
	# make prefix=/usr install install-doc install-html install-info ;# as root

	(or prefix=/usr/local, of course). Just like any program suite
	that uses $prefix, the built results have some paths encoded,
	which are derived from $prefix, so "make all; make prefix=/usr
	install" would not work.

	The beginning of the Makefile documents many variables that affect the way
	git is built. You can override them either from the command line, or in a
	config.mak file.

	Alternatively you can use autoconf generated ./configure script to
	set up install paths (via config.mak.autogen), so you can write instead

	$ make configure ;# as yourself
	$ ./configure --prefix=/usr ;# as yourself
	$ make all doc ;# as yourself
	# make install install-doc install-html;# as root

	If you're willing to trade off (much) longer build time for a later
	faster git you can also do a profile feedback build with

	$ make prefix=/usr profile
	# make prefix=/usr PROFILE=BUILD install

	This will run the complete test suite as training workload and then
	rebuild git with the generated profile feedback. This results in a git
	which is a few percent faster on CPU intensive workloads. This
	may be a good tradeoff for distribution packagers.

	Alternatively you can run profile feedback only with the git benchmark
	suite. This runs significantly faster than the full test suite, but
	has less coverage:

	$ make prefix=/usr profile-fast
	# make prefix=/usr PROFILE=BUILD install

	Or if you just want to install a profile-optimized version of git into
	your home directory, you could run:

	$ make profile-install

	or
	$ make profile-fast-install

	As a caveat: a profile-optimized build takes a lot longer since the
	git tree must be built twice, and in order for the profiling
	measurements to work properly, ccache must be disabled and the test
	suite has to be run using only a single CPU. In addition, the profile
	feedback build stage currently generates a lot of additional compiler
	warnings.

	Issues of note:

	- Ancient versions of GNU Interactive Tools (pre-4.9.2) installed a
	program "git", whose name conflicts with this program. But with
	version 4.9.2, after long hiatus without active maintenance (since
	around 1997), it changed its name to gnuit and the name conflict is no
	longer a problem.

	NOTE: When compiled with backward compatibility option, the GNU
	Interactive Tools package still can install "git", but you can build it
	with --disable-transition option to avoid this.

	- You can use git after building but without installing if you want
	to test drive it. Simply run git found in bin-wrappers directory
	in the build directory, or prepend that directory to your $PATH.
	This however is less efficient than running an installed git, as
	you always need an extra fork+exec to run any git subcommand.

	It is still possible to use git without installing by setting a few
	environment variables, which was the way this was done
	traditionally. But using git found in bin-wrappers directory in
	the build directory is far simpler. As a historical reference, the
	old way went like this:

	GIT_EXEC_PATH=`pwd`
	PATH=`pwd`:$PATH
	GITPERLLIB=`pwd`/perl/build/lib
	export GIT_EXEC_PATH PATH GITPERLLIB

	- By default (unless NO_PERL is provided) Git will ship various perl
	scripts. However, for simplicity it doesn't use the
	ExtUtils::MakeMaker toolchain to decide where to place the perl
	libraries. Depending on the system this can result in the perl
	libraries not being where you'd like them if they're expected to be
	used by things other than Git itself.

	Manually supplying a perllibdir prefix should fix this, if this is
	a problem you care about, e.g.:

	prefix=/usr perllibdir=/usr/$(/usr/bin/perl -MConfig -wle 'print substr $Config{installsitelib}, 1 + length $Config{siteprefixexp}')

	Will result in e.g. perllibdir=/usr/share/perl/5.26.1 on Debian,
	perllibdir=/usr/share/perl5 (which we'd use by default) on CentOS.

	- Unless NO_PERL is provided Git will ship various perl libraries it
	needs. Distributors of Git will usually want to set
	NO_PERL_CPAN_FALLBACKS if NO_PERL is not provided to use their own
	copies of the CPAN modules Git needs.

	- Git is reasonably self-sufficient, but does depend on a few external
	programs and libraries. Git can be used without most of them by adding
	the approriate "NO_<LIBRARY>=YesPlease" to the make command line or
	config.mak file.

	- "zlib", the compression library. Git won't build without it.

	- "ssh" is used to push and pull over the net.

	- A POSIX-compliant shell is required to run many scripts needed
	for everyday use (e.g. "bisect", "pull").

	- "Perl" version 5.8 or later is needed to use some of the
	features (e.g. preparing a partial commit using "git add -i/-p",
	interacting with svn repositories with "git svn"). If you can
	live without these, use NO_PERL. Note that recent releases of
	Redhat/Fedora are reported to ship Perl binary package with some
	core modules stripped away (see http://lwn.net/Articles/477234/),
	so you might need to install additional packages other than Perl
	itself, e.g. Digest::MD5, File::Spec, File::Temp, Net::Domain,
	Net::SMTP, and Time::HiRes.

	- git-imap-send needs the OpenSSL library to talk IMAP over SSL if
	you are using libcurl older than 7.34.0. Otherwise you can use
	NO_OPENSSL without losing git-imap-send.

	By default, git uses OpenSSL for SHA1 but it will use its own
	library (inspired by Mozilla's) with either NO_OPENSSL or
	BLK_SHA1. Also included is a version optimized for PowerPC
	(PPC_SHA1).

	- "libcurl" library is used by git-http-fetch, git-fetch, and, if
	the curl version >= 7.34.0, for git-imap-send. You might also
	want the "curl" executable for debugging purposes. If you do not
	use http:// or https:// repositories, and do not want to put
	patches into an IMAP mailbox, you do not have to have them
	(use NO_CURL).

	- "expat" library; git-http-push uses it for remote lock
	management over DAV. Similar to "curl" above, this is optional
	(with NO_EXPAT).

	- "wish", the Tcl/Tk windowing shell is used in gitk to show the
	history graphically, and in git-gui. If you don't want gitk or
	git-gui, you can use NO_TCLTK.

	- A gettext library is used by default for localizing Git. The
	primary target is GNU libintl, but the Solaris gettext
	implementation also works.

	We need a gettext.h on the system for C code, gettext.sh (or
	Solaris gettext(1)) for shell scripts, and libintl-perl for Perl
	programs.

	Set NO_GETTEXT to disable localization support and make Git only
	use English. Under autoconf the configure script will do this
	automatically if it can't find libintl on the system.

	- Python version 2.4 or later (but not 3.x, which is not
	supported by Perforce) is needed to use the git-p4 interface
	to Perforce.

	- Some platform specific issues are dealt with Makefile rules,
	but depending on your specific installation, you may not
	have all the libraries/tools needed, or you may have
	necessary libraries at unusual locations. Please look at the
	top of the Makefile to see what can be adjusted for your needs.
	You can place local settings in config.mak and the Makefile
	will include them. Note that config.mak is not distributed;
	the name is reserved for local settings.

	- To build and install documentation suite, you need to have
	the asciidoc/xmlto toolchain. Because not many people are
	inclined to install the tools, the default build target
	("make all") does _not_ build them.

	"make doc" builds documentation in man and html formats; there are
	also "make man", "make html" and "make info". Note that "make html"
	requires asciidoc, but not xmlto. "make man" (and thus make doc)
	requires both.

	"make install-doc" installs documentation in man format only; there
	are also "make install-man", "make install-html" and "make
	install-info".

	Building and installing the info file additionally requires
	makeinfo and docbook2X. Version 0.8.3 is known to work.

	Building and installing the pdf file additionally requires
	dblatex. Version >= 0.2.7 is known to work.

	All formats require at least asciidoc 8.4.1.

	There are also "make quick-install-doc", "make quick-install-man"
	and "make quick-install-html" which install preformatted man pages
	and html documentation. To use these build targets, you need to
	clone two separate git-htmldocs and git-manpages repositories next
	to the clone of git itself.

	It has been reported that docbook-xsl version 1.72 and 1.73 are
	buggy; 1.72 misformats manual pages for callouts, and 1.73 needs
	the patch in contrib/patches/docbook-xsl-manpages-charmap.patch

	Users attempting to build the documentation on Cygwin may need to ensure
	that the /etc/xml/catalog file looks something like this:

	<?xml version="1.0"?>
	<!DOCTYPE catalog PUBLIC
	"-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
	"http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"
	>
	<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
	<rewriteURI
	uriStartString = "http://docbook.sourceforge.net/release/xsl/current"
	rewritePrefix = "/usr/share/sgml/docbook/xsl-stylesheets"
	/>
	<rewriteURI
	uriStartString="http://www.oasis-open.org/docbook/xml/4.5"
	rewritePrefix="/usr/share/sgml/docbook/xml-dtd-4.5"
	/>
	</catalog>

	This can be achieved with the following two xmlcatalog commands:

	xmlcatalog --noout \
	--add rewriteURI \
	http://docbook.sourceforge.net/release/xsl/current \
	/usr/share/sgml/docbook/xsl-stylesheets \
	/etc/xml/catalog

	xmlcatalog --noout \
	--add rewriteURI \
	http://www.oasis-open.org/docbook/xml/4.5/xsl/current \
	/usr/share/sgml/docbook/xml-dtd-4.5 \
	/etc/xml/catalog