git

1

2
		Git installation
3

4
Normally you can just do "make" followed by "make install", and that
5
will install the git programs in your own ~/bin/ directory.  If you want
6
to do a global install, you can do
7

8
	$ make prefix=/usr all doc info ;# as yourself
9
	# make prefix=/usr install install-doc install-html install-info ;# as root
10

11
(or prefix=/usr/local, of course).  Just like any program suite
12
that uses $prefix, the built results have some paths encoded,
13
which are derived from $prefix, so "make all; make prefix=/usr
14
install" would not work.
15

16
The beginning of the Makefile documents many variables that affect the way
17
git is built.  You can override them either from the command line, or in a
18
config.mak file.
19

20
Alternatively you can use autoconf generated ./configure script to
21
set up install paths (via config.mak.autogen), so you can write instead
22

23
	$ make configure ;# as yourself
24
	$ ./configure --prefix=/usr ;# as yourself
25
	$ make all doc ;# as yourself
26
	# make install install-doc install-html;# as root
27

28
If you're willing to trade off (much) longer build time for a later
29
faster git you can also do a profile feedback build with
30

31
	$ make prefix=/usr profile
32
	# make prefix=/usr PROFILE=BUILD install
33

34
This will run the complete test suite as training workload and then
35
rebuild git with the generated profile feedback. This results in a git
36
which is a few percent faster on CPU intensive workloads.  This
37
may be a good tradeoff for distribution packagers.
38

39
Alternatively you can run profile feedback only with the git benchmark
40
suite. This runs significantly faster than the full test suite, but
41
has less coverage:
42

43
	$ make prefix=/usr profile-fast
44
	# make prefix=/usr PROFILE=BUILD install
45

46
Or if you just want to install a profile-optimized version of git into
47
your home directory, you could run:
48

49
	$ make profile-install
50

51
or
52
	$ make profile-fast-install
53

54
As a caveat: a profile-optimized build takes a *lot* longer since the
55
git tree must be built twice, and in order for the profiling
56
measurements to work properly, ccache must be disabled and the test
57
suite has to be run using only a single CPU.  In addition, the profile
58
feedback build stage currently generates a lot of additional compiler
59
warnings.
60

61
Issues of note:
62

63
 - Ancient versions of GNU Interactive Tools (pre-4.9.2) installed a
64
   program "git", whose name conflicts with this program.  But with
65
   version 4.9.2, after long hiatus without active maintenance (since
66
   around 1997), it changed its name to gnuit and the name conflict is no
67
   longer a problem.
68

69
   NOTE: When compiled with backward compatibility option, the GNU
70
   Interactive Tools package still can install "git", but you can build it
71
   with --disable-transition option to avoid this.
72

73
 - You can use git after building but without installing if you want
74
   to test drive it.  Simply run git found in bin-wrappers directory
75
   in the build directory, or prepend that directory to your $PATH.
76
   This however is less efficient than running an installed git, as
77
   you always need an extra fork+exec to run any git subcommand.
78

79
   It is still possible to use git without installing by setting a few
80
   environment variables, which was the way this was done
81
   traditionally.  But using git found in bin-wrappers directory in
82
   the build directory is far simpler.  As a historical reference, the
83
   old way went like this:
84

85
	GIT_EXEC_PATH=`pwd`
86
	PATH=`pwd`:$PATH
87
	GITPERLLIB=`pwd`/perl/build/lib
88
	export GIT_EXEC_PATH PATH GITPERLLIB
89

90
 - By default (unless NO_PERL is provided) Git will ship various perl
91
   scripts. However, for simplicity it doesn't use the
92
   ExtUtils::MakeMaker toolchain to decide where to place the perl
93
   libraries. Depending on the system this can result in the perl
94
   libraries not being where you'd like them if they're expected to be
95
   used by things other than Git itself.
96

97
   Manually supplying a perllibdir prefix should fix this, if this is
98
   a problem you care about, e.g.:
99

100
       prefix=/usr perllibdir=/usr/$(/usr/bin/perl -MConfig -wle 'print substr $Config{installsitelib}, 1 + length $Config{siteprefixexp}')
101

102
   Will result in e.g. perllibdir=/usr/share/perl/5.26.1 on Debian,
103
   perllibdir=/usr/share/perl5 (which we'd use by default) on CentOS.
104

105
 - Unless NO_PERL is provided Git will ship various perl libraries it
106
   needs. Distributors of Git will usually want to set
107
   NO_PERL_CPAN_FALLBACKS if NO_PERL is not provided to use their own
108
   copies of the CPAN modules Git needs.
109

110
 - Git is reasonably self-sufficient, but does depend on a few external
111
   programs and libraries.  Git can be used without most of them by adding
112
   the appropriate "NO_<LIBRARY>=YesPlease" to the make command line or
113
   config.mak file.
114

115
	- "zlib", the compression library. Git won't build without it.
116

117
	- "ssh" is used to push and pull over the net.
118

119
	- A POSIX-compliant shell is required to run some scripts needed
120
	  for everyday use (e.g. "bisect", "request-pull").
121

122
	- "Perl" version 5.8.1 or later is needed to use some of the
123
	  features (e.g. sending patches using "git send-email",
124
	  interacting with svn repositories with "git svn").  If you can
125
	  live without these, use NO_PERL.  Note that recent releases of
126
	  Redhat/Fedora are reported to ship Perl binary package with some
127
	  core modules stripped away (see https://lwn.net/Articles/477234/),
128
	  so you might need to install additional packages other than Perl
129
	  itself, e.g. Digest::MD5, File::Spec, File::Temp, Net::Domain,
130
	  Net::SMTP, and Time::HiRes.
131

132
	- git-imap-send needs the OpenSSL library to talk IMAP over SSL if
133
	  you are using libcurl older than 7.34.0.  Otherwise you can use
134
	  NO_OPENSSL without losing git-imap-send.
135

136
	- "libcurl" library is used for fetching and pushing
137
	  repositories over http:// or https://, as well as by
138
	  git-imap-send if the curl version is >= 7.34.0. If you do
139
	  not need that functionality, use NO_CURL to build without
140
	  it.
141

142
	  Git requires version "7.21.3" or later of "libcurl" to build
143
	  without NO_CURL. This version requirement may be bumped in
144
	  the future.
145

146
	- "expat" library; git-http-push uses it for remote lock
147
	  management over DAV.  Similar to "curl" above, this is optional
148
	  (with NO_EXPAT).
149

150
	- "wish", the Tcl/Tk windowing shell is used in gitk to show the
151
	  history graphically, and in git-gui.  If you don't want gitk or
152
	  git-gui, you can use NO_TCLTK.
153

154
	- A gettext library is used by default for localizing Git. The
155
	  primary target is GNU libintl, but the Solaris gettext
156
	  implementation also works.
157

158
	  We need a gettext.h on the system for C code, gettext.sh (or
159
	  Solaris gettext(1)) for shell scripts, and libintl-perl for Perl
160
	  programs.
161

162
	  Set NO_GETTEXT to disable localization support and make Git only
163
	  use English. Under autoconf the configure script will do this
164
	  automatically if it can't find libintl on the system.
165

166
	- Python version 2.7 or later is needed to use the git-p4 interface
167
	  to Perforce.
168

169
 - Some platform specific issues are dealt with Makefile rules,
170
   but depending on your specific installation, you may not
171
   have all the libraries/tools needed, or you may have
172
   necessary libraries at unusual locations.  Please look at the
173
   top of the Makefile to see what can be adjusted for your needs.
174
   You can place local settings in config.mak and the Makefile
175
   will include them.  Note that config.mak is not distributed;
176
   the name is reserved for local settings.
177

178
 - To build and install documentation suite, you need to have
179
   the asciidoc/xmlto toolchain.  Because not many people are
180
   inclined to install the tools, the default build target
181
   ("make all") does _not_ build them.
182

183
   "make doc" builds documentation in man and html formats; there are
184
   also "make man", "make html" and "make info". Note that "make html"
185
   requires asciidoc, but not xmlto. "make man" (and thus make doc)
186
   requires both.
187

188
   "make install-doc" installs documentation in man format only; there
189
   are also "make install-man", "make install-html" and "make
190
   install-info".
191

192
   Building and installing the info file additionally requires
193
   makeinfo and docbook2X.  Version 0.8.3 is known to work.
194

195
   Building and installing the pdf file additionally requires
196
   dblatex.  Version >= 0.2.7 is known to work.
197

198
   All formats require at least asciidoc 8.4.1. Alternatively, you can
199
   use Asciidoctor (requires Ruby) by passing USE_ASCIIDOCTOR=YesPlease
200
   to make. You need at least Asciidoctor version 1.5.
201

202
   There are also "make quick-install-doc", "make quick-install-man"
203
   and "make quick-install-html" which install preformatted man pages
204
   and html documentation. To use these build targets, you need to
205
   clone two separate git-htmldocs and git-manpages repositories next
206
   to the clone of git itself.
207

208
   The minimum supported version of docbook-xsl is 1.74.
209

210
   Users attempting to build the documentation on Cygwin may need to ensure
211
   that the /etc/xml/catalog file looks something like this:
212

213
   <?xml version="1.0"?>
214
   <!DOCTYPE catalog PUBLIC
215
      "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
216
      "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"
217
   >
218
   <catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
219
     <rewriteURI
220
       uriStartString = "http://docbook.sourceforge.net/release/xsl/current"
221
       rewritePrefix = "/usr/share/sgml/docbook/xsl-stylesheets"
222
     />
223
     <rewriteURI
224
       uriStartString="http://www.oasis-open.org/docbook/xml/4.5"
225
       rewritePrefix="/usr/share/sgml/docbook/xml-dtd-4.5"
226
     />
227
  </catalog>
228

229
  This can be achieved with the following two xmlcatalog commands:
230

231
  xmlcatalog --noout \
232
     --add rewriteURI \
233
        http://docbook.sourceforge.net/release/xsl/current \
234
        /usr/share/sgml/docbook/xsl-stylesheets \
235
     /etc/xml/catalog
236

237
  xmlcatalog --noout \
238
     --add rewriteURI \
239
         http://www.oasis-open.org/docbook/xml/4.5/xsl/current \
240
         /usr/share/sgml/docbook/xml-dtd-4.5 \
241
     /etc/xml/catalog
242