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 appropriate "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 some scripts needed

for everyday use (e.g. "bisect", "request-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.

- "libcurl" library is used for fetching and pushing

repositories over http:// or https://, as well as by

git-imap-send if the curl version is >= 7.34.0. If you do

not need that functionality, use NO_CURL to build without

it.

Git requires version "7.19.4" or later of "libcurl" to build

without NO_CURL. This version requirement may be bumped in

the future.

- "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 2.7 or later 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. Alternatively, you can

use Asciidoctor (requires Ruby) by passing USE_ASCIIDOCTOR=YesPlease

to make. You need at least Asciidoctor version 1.5.

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.

The minimum supported version of docbook-xsl is 1.74.

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