Rename `image-library-alist' to `dynamic-library-alist'.
[bpt/emacs.git] / nt / INSTALL
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1 Building and Installing Emacs on Windows
2 (from 95 to 7 and beyond)
a4a9692d 3
114f9c96 4 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
0939da72 5 Free Software Foundation, Inc.
7f6d64f8 6 See the end of the file for license conditions.
4b994b84 7
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8* For the impatient
9
10 Here are the concise instructions for configuring and building the
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11 native Windows binary of Emacs, for those who want to skip the
12 complex explanations and ``just do it'':
0939da72 13
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14 Do not use this recipe with Cygwin. For building on Cygwin,
15 use the normal installation instructions, ../INSTALL.
16
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17 1. Change to the `nt' directory (the directory of this file):
18
19 cd nt
20
21 2. Run configure.bat. From the COMMAND.COM/CMD.EXE command prompt:
22
23 configure
24
25 from a Unixy shell prompt:
26
27 cmd /c configure.bat
28 or
29 command.com /c configure.bat
30
31 3. Run the Make utility suitable for your environment. If you build
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32 with the Microsoft's Visual C compiler (but see notes about using
33 VC++ 8.0 and later below):
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34
35 nmake
36
37 For the development environments based on GNU GCC (MinGW, MSYS,
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38 Cygwin - but see notes about Cygwin make below), depending on how
39 Make is called, it could be:
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40
41 make
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42 or
43 mingw32-make
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44 or
45 gnumake
46 or
47 gmake
48
ee6f37f2 49 (If you are building from Bazaar, say "make bootstrap" or "nmake
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50 bootstrap" instead, and avoid using Cygwin make.)
51
52 With GNU Make, you can use the -j command-line option to have
53 Make execute several commands at once, like this:
54
ecfd8ceb 55 gmake -j 2 XMFLAGS="-j 2"
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56
57 The XMFLAGS variable overrides the default behavior of GNU Make
58 on Windows, whereby recursive Make invocations reset the maximum
59 number of simultaneous commands to 1. The above command allows
60 up to 4 simultaneous commands at once in the top-level Make, and
61 up to 3 in each one of the recursive Make's.
0939da72 62
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63 4. Generate the Info manuals (only if you are building out of Bazaar,
64 and if you have makeinfo.exe installed):
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65
66 make info
67
68 (change "make" to "nmake" if you use MSVC).
69
70 5. Install the produced binaries:
71
72 make install
73
74 That's it!
75
76 If these short instructions somehow fail, read the rest of this
77 file.
78
79* Preliminaries
80
195e32b7 81 If you want to build a Cygwin port of Emacs, use the instructions in
0d801288 82 the INSTALL file in the main Emacs directory (the parent of this
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83 directory). These instructions are for building a native Windows
84 binary of Emacs.
85
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86 If you used WinZip to unpack the distribution, we suggest to
87 remove the files and unpack again with a different program!
88 WinZip is known to create some subtle and hard to debug problems,
177c0ea7 89 such as converting files to DOS CR-LF format, not creating empty
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90 directories, etc. We suggest to use djtarnt.exe from the GNU FTP
91 site.
92
ee6f37f2 93 In addition to this file, you should also read INSTALL.BZR in the
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94 parent directory, and make sure that you have a version of
95 "touch.exe" in your path, and that it will create files that do not
96 yet exist.
589a591b 97
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98* Supported development environments
99
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100 To compile Emacs, you will need either Microsoft Visual C++ 2.0, or
101 later up to 7.0, and nmake, or a Windows port of GCC 2.95 or later
102 with MinGW and W32 API support and a port of GNU Make. You can use
103 the Cygwin ports of GCC, but Emacs requires the MinGW headers and
104 libraries to build (latest versions of the Cygwin toolkit, at least
105 since v1.3.3, include the MinGW headers and libraries as an integral
106 part).
107
108 Note that building Emacs with Visual Studio 2005 (VC++ 8.0) is not
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109 supported at this time, due to changes introduced by Microsoft into
110 the libraries shipped with the compiler.
ecfd8ceb 111
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112 The rest of this file assumes you have a working development
113 environment. If you just installed such an environment, try
114 building a trivial C "Hello world" program, and see if it works. If
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115 it doesn't work, resolve that problem first! If you use Microsoft
116 Visual Studio .NET 2003, don't forget to run the VCVARS32.BAT batch
117 file from the `Bin' subdirectory of the directory where you have
118 installed VS.NET.
0939da72 119
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120 If you use the MinGW port of GCC and GNU Make to build Emacs, there
121 are some compatibility issues wrt Make and the shell that is run by
122 Make, either the standard COMMAND.COM/CMD.EXE supplied with Windows
6d96d18f 123 or sh.exe, a port of a Unixy shell. For reference, below is a list
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124 of which builds of GNU Make are known to work or not, and whether
125 they work in the presence and/or absence of sh.exe, the Cygwin port
1640b452 126 of Bash. Note that any version of Make that is compiled with Cygwin
6d96d18f 127 will only work with Cygwin tools, due to the use of Cygwin style
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128 paths. This means Cygwin Make is unsuitable for building parts of
129 Emacs that need to invoke Emacs itself (leim and "make bootstrap",
130 for example). Also see the Trouble-shooting section below if you
131 decide to go ahead and use Cygwin make.
b147d297 132
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133 In addition, using 4NT or TCC as your shell is known to fail the build
134 process, at least since 4NT version 3.01. Use CMD.EXE, the default
135 Windows shell, instead. MSYS sh.exe also appears to cause various
136 problems. If you have MSYS installed, try "make SHELL=cmd.exe" to
137 force the use of cmd.exe instead of sh.exe.
177c0ea7 138
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139 sh exists no sh
140
fc813ef6 141 cygwin b20.1 make (3.75): fails[1, 5] fails[2, 5]
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142 MSVC compiled gmake 3.77: okay okay
143 MSVC compiled gmake 3.78.1: okay okay
144 MSVC compiled gmake 3.79.1: okay okay
bf95665f 145 mingw32/gcc-2.92.2 make (3.77): okay okay[4]
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146 cygwin compiled gmake 3.77: fails[1, 5] fails[2, 5]
147 cygwin compiled make 3.78.1: fails[5] fails[2, 5]
148 cygwin compiled make 3.79.1: fails[3, 5] fails[2?, 5]
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149 cygwin compiled make 3.80: okay[6] fails?[7]
150 cygwin compiled make 3.81: fails fails?[7]
177c0ea7 151 mingw32 compiled make 3.79.1: okay okay
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152 mingw32 compiled make 3.80: okay okay[7]
153 mingw32 compiled make 3.81: okay okay[8]
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154
155 Notes:
156
157 [1] doesn't cope with makefiles with DOS line endings, so must mount
158 emacs source with text!=binary.
159 [2] fails when needs to invoke shell commands; okay invoking gcc etc.
fc813ef6 160 [3] requires LC_MESSAGES support to build; cannot build with early
a917e3f2 161 versions of Cygwin.
4bcec9a2 162 [4] may fail on Windows 9X and Windows ME; if so, install Bash.
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163 [5] fails when building leim due to the use of cygwin style paths.
164 May work if building emacs without leim.
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165 [6] need to uncomment 3 lines in nt/gmake.defs that invoke `cygpath'
166 (look for "cygpath" near line 85 of gmake.defs).
167 [7] not recommended; please report if you try this combination.
168 [8] tested only on Windows XP.
4bcec9a2 169
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170 Other compilers may work, but specific reports from people that have
171 tried suggest that the Intel C compiler (for example) may produce an
5739d6f8 172 Emacs executable with strange filename completion behavior. Unless
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173 you would like to assist by finding and fixing the cause of any bugs
174 like this, we recommend the use of the supported compilers mentioned
175 in the previous paragraph.
176
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177 You will also need a copy of the POSIX cp, rm and mv programs. These
178 and other useful POSIX utilities can be obtained from one of several
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179 projects:
180
0939da72 181 * http://gnuwin32.sourceforge.net/ ( GnuWin32 )
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182 * http://www.mingw.org/ ( MinGW )
183 * http://www.cygwin.com/ ( Cygwin )
184 * http://unxutils.sourceforge.net/ ( UnxUtils )
6c72c0c7 185
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186 If you build Emacs on 16-bit versions of Windows (9X or ME), we
187 suggest to install the Cygwin port of Bash. That is because the
188 native Windows shell COMMAND.COM is too limited; the Emacs build
189 procedure tries very hard to support even such limited shells, but
190 as none of the Windows developers of Emacs work on Windows 9X, we
191 cannot guarantee that it works without a more powerful shell.
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192
193 Additional instructions and help for building Emacs on Windows can be
194 found at the Emacs Wiki:
195
0939da72 196 http://www.emacswiki.org/cgi-bin/wiki/WThirtyTwoInstallationKit
6c72c0c7 197
309c91ff 198 and on these URLs:
6c72c0c7 199
0939da72 200 http://ourcomments.org/Emacs/w32-build-emacs.html
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201 http://derekslager.com/blog/posts/2007/01/emacs-hack-3-compile-emacs-from-cvs-on-windows.ashx
202
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203 Both of those pages were written before Emacs switched from CVS to
204 Bazaar, but the parts about building Emacs still apply in Bazaar.
205 The second URL has instructions for building with MSVC, as well as
206 with MinGW, while the first URL covers only MinGW, but has more
207 details about it.
6c72c0c7 208
6d76a603 209* Configuring
a4a9692d 210
da179dd0 211 Configuration of Emacs is now handled by running configure.bat in the
0939da72 212 `nt' subdirectory. It will detect which compiler you have available,
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213 and generate makefiles accordingly. You can override the compiler
214 detection, and control optimization and debug settings, by specifying
215 options on the command line when invoking configure.
a4a9692d 216
da179dd0 217 To configure Emacs to build with GCC or MSVC, whichever is available,
0939da72 218 simply change to the `nt' subdirectory and run `configure.bat' with no
da179dd0 219 options. To see what options are available, run `configure --help'.
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220 Do NOT use the --no-debug option to configure.bat unless you are
221 absolutely sure the produced binaries will never need to be run under
222 a debugger.
a4a9692d 223
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224 Because of limitations of the stock Windows command shell, certain
225 characters (quotes, backslashes and equal signs) can be problematic
226 and should not be used in arguments to configure. That means that
227 forward slashes must be used in paths passed to the compiler and
228 linker via the --cflags and --ldflags options, and that it is
229 currently not possible to pass a macro like -DFOO=BAR (though -DFOO
230 is perfectly valid).
231
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232 N.B. It is normal to see a few error messages output while configure
233 is running, when gcc support is being tested. These cannot be
a917e3f2 234 suppressed because of limitations in the Windows 9X command.com shell.
17d4e22c 235
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236 You are encouraged to look at the file config.log which shows details
237 for failed tests, after configure.bat finishes. Any unexplained failure
238 should be investigated and perhaps reported as a bug (see the section
239 about reporting bugs in the file README in this directory and in the
240 Emacs manual).
241
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242* Optional image library support
243
3dfbc6d8 244 In addition to its "native" image formats (pbm and xbm), Emacs can
8bc63b1a 245 handle other image types: xpm, tiff, gif, png, jpeg and experimental
707a78b2 246 support for svg.
6d96d18f 247
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248 To build Emacs with support for them, the corresponding headers must
249 be in the include path when the configure script is run. This can
250 be setup using environment variables, or by specifying --cflags
251 -I... options on the command-line to configure.bat. The configure
252 script will report whether it was able to detect the headers. If
253 the results of this testing appear to be incorrect, please look for
254 details in the file config.log: it will show the failed test
255 programs and compiler error messages that should explain what is
256 wrong. (Usually, any such failures happen because some headers are
257 missing due to bad packaging of the image support libraries.)
bfd889ed 258
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259 Note that any file path passed to the compiler or linker must use
260 forward slashes; using backslashes will cause compiler warnings or
261 errors about unrecognized escape sequences.
262
3dfbc6d8 263 To use the external image support, the DLLs implementing the
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264 functionality must be found when Emacs first needs them, either on the
265 PATH, or in the same directory as emacs.exe. Failure to find a
266 library is not an error; the associated image format will simply be
267 unavailable. Note that once Emacs has determined that a library can
268 not be found, there's no way to force it to try again, other than
2e288d54 269 restarting. See the variable `dynamic-library-alist' to configure the
bd7bdff8 270 expected names of the libraries.
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271
272 Some image libraries have dependencies on one another, or on zlib.
273 For example, tiff support depends on the jpeg library. If you did not
274 compile the libraries yourself, you must make sure that any dependency
5739d6f8 275 is in the PATH or otherwise accessible and that the binaries are
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276 compatible (for example, that they were built with the same compiler).
277
278 Binaries for the image libraries (among many others) can be found at
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279 the GnuWin32 project. PNG, JPEG and TIFF libraries are also
280 included with GTK, which is installed along with other Free Software
281 that requires it. These are built with MinGW, but they can be used
282 with both GCC/MinGW and MSVC builds of Emacs. See the info on
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283 http://ourcomments.org/Emacs/w32-build-emacs.html, under "How to Get
284 Images Support", for more details about installing image support
285 libraries. Note specifically that, due to some packaging snafus in
286 the GnuWin32-supplied image libraries, you will need to download
287 _source_ packages for some of the libraries in order to get the
288 header files necessary for building Emacs with image support.
bfd889ed 289
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290 If GTK 2.0 is installed, addpm will arrange for its image libraries
291 to be on the DLL search path for Emacs.
292
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293* Experimental SVG support
294
295 SVG support is currently experimental, and not built by default.
296 Specify --with-svg and ensure you have all the dependencies in your
1640b452 297 include path. Unless you have built a minimalist librsvg yourself
8bc63b1a 298 (untested), librsvg depends on a significant chunk of GTK+ to build,
1640b452 299 plus a few Gnome libraries, libxml2, libbz2 and zlib at runtime. The
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300 easiest way to obtain the dependencies required for building is to
301 download a pre-bundled GTK+ development environment for Windows.
302 GTK puts its header files all over the place, so you will need to
303 run pkgconfig to list the include path you will need (either passed
304 to configure.bat as --cflags options, or set in the environment).
305
306 To use librsvg at runtime, ensure that librsvg and its dependencies
307 are on your PATH. If you didn't build librsvg yourself, you will
308 need to check with where you downloaded it from for the
309 dependencies, as there are different build options. If it is a
310 short list, then it most likely only lists the immediate
311 dependencies of librsvg, but the dependencies themselves have
312 dependencies - so don't download individual libraries from GTK+,
1640b452 313 download and install the whole thing. If you think you've got all
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314 the dependencies and SVG support is still not working, check your
315 PATH for other libraries that shadow the ones you downloaded.
316 Libraries of the same name from different sources may not be
317 compatible, this problem was encountered with libbzip2 from GnuWin32
318 with libcroco from gnome.org.
319
320 If you can see etc/images/splash.svg, then you have managed to get
321 SVG support working. Congratulations for making it through DLL hell
1640b452 322 to this point. You'll probably find that some SVG images crash
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323 Emacs. Problems have been observed in some images that contain
324 text, they seem to be a problem in the Windows port of Pango, or
325 maybe a problem with the way Cairo or librsvg is using it that
326 doesn't show up on other platforms.
327
6d76a603 328* Building
a4a9692d 329
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330 After running configure, simply run the appropriate `make' program for
331 your compiler to build Emacs. For MSVC, this is nmake; for GCC, it is
ee6f37f2 332 GNU make. (If you are building out of Bazaar, say "make bootstrap" or
0939da72 333 "nmake bootstrap" instead.)
a4a9692d 334
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335 As the files are compiled, you will see some warning messages
336 declaring that some functions don't return a value, or that some data
337 conversions will be lossy, etc. You can safely ignore these messages.
338 The warnings may be fixed in the main FSF source at some point, but
339 until then we will just live with them.
a4a9692d 340
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341 With GNU Make, you can use the -j command-line option to have Make
342 execute several commands at once, like this:
343
344 gmake -j 4 XMFLAGS="-j 3"
345
346 The XMFLAGS variable overrides the default behavior of GNU Make on
347 Windows, whereby recursive Make invocations reset the maximum number
348 of simultaneous commands to 1. The above command allows up to 4
349 simultaneous commands at once in the top-level Make, and up to 3 in
350 each one of the recursive Make's; you can use other numbers of jobs,
351 if you wish.
352
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353 If you are building from Bazaar, the following commands will produce
354 the Info manuals (which are not part of the Bazaar sources):
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355
356 make info
357 or
358 nmake info
359
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360 Note that you will need makeinfo.exe (from the GNU Texinfo package)
361 in order for this command to succeed.
362
6d76a603 363* Installing
a4a9692d 364
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365 To install Emacs after it has compiled, simply run `nmake install'
366 or `make install', depending on which version of the Make utility
367 do you have.
a4a9692d 368
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369 By default, Emacs will be installed in the location where it was
370 built, but a different location can be specified either using the
371 --prefix option to configure, or by setting INSTALL_DIR when running
372 make, like so:
a4a9692d 373
da179dd0 374 make install INSTALL_DIR=D:/emacs
a4a9692d 375
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376 (for `nmake', type "nmake install INSTALL_DIR=D:/emacs" instead).
377
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378 The install process will run addpm to setup the registry entries, and
379 to create a Start menu icon for Emacs.
a4a9692d 380
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381* Make targets
382
383 The following make targets may be used by users building the source
ee6f37f2 384 distribution, or users who have checked out of Bazaar after
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385 an initial bootstrapping.
386
387 make
388 Builds Emacs from the available sources and pre-compiled lisp files.
389
390 make install
391 Installs programs to the bin directory, and runs addpm to create
392 Start Menu icons.
393
394 make clean
395 Removes object and executable files produced by the build process in
396 the current configuration. After make clean, you can rebuild with
397 the same configuration using make.
398
399 make distclean
400 In addition to the files removed by make clean, this also removes
401 Makefiles and other generated files to get back to the state of a
1640b452 402 freshly unpacked source distribution. Note that this will not remove
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403 installed files, or the results of builds performed with different
404 compiler or optimization options than the current configuration.
405 After make distclean, it is necessary to run configure.bat followed
406 by make to rebuild.
407
408 make cleanall
409 Removes object and executable files that may have been created by
410 previous builds with different configure options, in addition to
411 the files produced by the current configuration.
412
413 make realclean
414 Removes the installed files in the bin subdirectory in addition to
415 the files removed by make cleanall.
416
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417 make dist
418 Builds Emacs from the available sources and pre-compiled lisp files.
419 Packages Emacs binaries as full distribution and barebin distribution.
5739d6f8 420
ee6f37f2 421 The following targets are intended only for use with the Bazaar sources.
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422
423 make bootstrap
424 Creates a temporary emacs binary with lisp source files and
425 uses it to compile the lisp files. Once the lisp files are built,
426 emacs is redumped with the compiled lisp.
427
428 make recompile
ee6f37f2 429 Recompiles any changed lisp files after an update. This saves
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430 doing a full bootstrap after every update. If this or a subsequent
431 make fail, you probably need to perform a full bootstrap, though
432 running this target multiple times may eventually sort out the
433 interdependencies.
434
435 make maintainer-clean
436 Removes everything that can be recreated, including compiled lisp
ee6f37f2 437 files, to get back to the state of a fresh Bazaar tree. After make
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438 maintainer-clean, it is necessary to run configure.bat and make
439 bootstrap to rebuild. Occasionally it may be necessary to run this
ee6f37f2 440 target after an update.
5739d6f8 441
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442* Creating binary distributions
443
444 Binary distributions (full and barebin distributions) can be
445 automatically built and packaged from source tarballs or a bzr
446 checkout.
447
448 When building Emacs binary distributions, the --distfiles argument
449 to configure.bat specifies files to be included in the bin directory
450 of the binary distributions. This is intended for libraries that are
451 not built as part of Emacs, e.g. image libraries.
452
453 For example, specifying
454
455 --distfiles D:\distfiles\libXpm.dll
456
457 results in libXpm.dll being copied from D:\distfiles to the
458 bin directory before packaging starts.
459
460 Multiple files can be specified using multiple --distfiles arguments:
461
462 --distfiles D:\distfiles\libXpm.dll --distfiles C:\jpeglib\jpeg.dll
463
464 For packaging the binary distributions, the 'dist' make target uses
465 7-Zip (http://www.7-zip.org), which must be installed and available
466 on the Windows Path.
467
5739d6f8 468
6d76a603 469* Trouble-shooting
a4a9692d 470
da179dd0 471 The main problems that are likely to be encountered when building
bd7bdff8 472 Emacs stem from using an old version of GCC, or old MinGW or W32 API
a917e3f2 473 headers. Additionally, Cygwin ports of GNU make may require the Emacs
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474 source tree to be mounted with text!=binary, because the makefiles
475 generated by configure.bat necessarily use DOS line endings. Also,
a917e3f2 476 Cygwin ports of make must run in UNIX mode, either by specifying
da179dd0 477 --unix on the command line, or MAKE_MODE=UNIX in the environment.
a4a9692d 478
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479 When configure runs, it attempts to detect when GCC itself, or the
480 headers it is using, are not suitable for building Emacs. GCC version
481 2.95 or later is needed, because that is when the Windows port gained
482 sufficient support for anonymous structs and unions to cope with some
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483 definitions from winnt.h that are used by addsection.c.
484 Older versions of the W32 API headers that come with Cygwin and MinGW
485 may be missing some definitions required by Emacs, or broken in other
4a00b4b3 486 ways. In particular, uniscribe APIs were added to MinGW CVS only on
a25fe288 487 2006-03-26, so releases from before then cannot be used.
a4a9692d 488
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489 When in doubt about correctness of what configure did, look at the file
490 config.log, which shows all the failed test programs and compiler
491 messages associated with the failures. If that doesn't give a clue,
492 please report the problems, together with the relevant fragments from
493 config.log, as bugs.
494
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495 If configure succeeds, but make fails, install the Cygwin port of
496 Bash, even if the table above indicates that Emacs should be able to
497 build without sh.exe. (Some versions of Windows shells are too dumb
498 for Makefile's used by Emacs.)
499
8481e41e 500 If you are using certain Cygwin builds of GCC, such as Cygwin version
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501 1.1.8, you may need to specify some extra compiler flags like so:
502
503 configure --with-gcc --cflags -mwin32 --cflags -D__MSVCRT__
315746cc 504 --ldflags -mwin32
6d76a603 505
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506 However, the latest Cygwin versions, such as 1.3.3, don't need those
507 switches; you can simply use "configure --with-gcc".
508
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509 We will attempt to auto-detect the need for these flags in a future
510 release.
511
512* Debugging
a4a9692d 513
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514 You should be able to debug Emacs using the debugger that is
515 appropriate for the compiler you used, namely DevStudio or Windbg if
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516 compiled with MSVC, or GDB if compiled with GCC. (GDB for Windows
517 is available from the MinGW site, http://www.mingw.org/download.shtml.)
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518
519 When Emacs aborts due to a fatal internal error, Emacs on Windows
520 pops up an Emacs Abort Dialog asking you whether you want to debug
521 Emacs or terminate it. If Emacs was built with MSVC, click YES
522 twice, and Windbg or the DevStudio debugger will start up
523 automatically. If Emacs was built with GCC, first start GDB and
524 attach it to the Emacs process with the "gdb -p EMACS-PID" command,
525 where EMACS-PID is the Emacs process ID (which you can see in the
526 Windows Task Manager), type the "continue" command inside GDB, and
527 only then click YES on the abort dialog. This will pass control to
528 the debugger, and you will be able to debug the cause of the fatal
529 error.
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530
531 Emacs functions implemented in C use a naming convention that reflects
532 their names in lisp. The names of the C routines are the lisp names
533 prefixed with 'F', and with dashes converted to underscores. For
534 example, the function call-process is implemented in C by
535 Fcall_process. Similarly, lisp variables are prefixed with 'V', again
536 with dashes converted to underscores. These conventions enable you to
537 easily set breakpoints or examine familiar lisp variables by name.
538
539 Since Emacs data is often in the form of a lisp object, and the
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540 Lisp_Object type is difficult to examine manually in a debugger,
541 Emacs provides a helper routine called debug_print that prints out a
542 readable representation of a Lisp_Object. If you are using GDB,
543 there is a .gdbinit file in the src directory which provides
544 definitions that are useful for examining lisp objects. Therefore,
545 the following tips are mainly of interest when using MSVC.
546
547 The output from debug_print is sent to stderr, and to the debugger
548 via the OutputDebugString routine. The output sent to stderr should
549 be displayed in the console window that was opened when the
550 emacs.exe executable was started. The output sent to the debugger
551 should be displayed in its "Debug" output window.
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552
553 When you are in the process of debugging Emacs and you would like to
5739d6f8 554 examine the contents of a Lisp_Object variable, pop up the QuickWatch
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555 window (QuickWatch has an eyeglass symbol on its button in the
556 toolbar). In the text field at the top of the window, enter
557 debug_print(<variable>) and hit return. For example, start and run
558 Emacs in the debugger until it is waiting for user input. Then click
559 on the Break button in the debugger to halt execution. Emacs should
560 halt in ZwUserGetMessage waiting for an input event. Use the Call
561 Stack window to select the procedure w32_msp_pump up the call stack
562 (see below for why you have to do this). Open the QuickWatch window
563 and enter debug_print(Vexec_path). Evaluating this expression will
564 then print out the contents of the lisp variable exec-path.
565
566 If QuickWatch reports that the symbol is unknown, then check the call
567 stack in the Call Stack window. If the selected frame in the call
568 stack is not an Emacs procedure, then the debugger won't recognize
569 Emacs symbols. Instead, select a frame that is inside an Emacs
570 procedure and try using debug_print again.
571
572 If QuickWatch invokes debug_print but nothing happens, then check the
573 thread that is selected in the debugger. If the selected thread is
574 not the last thread to run (the "current" thread), then it cannot be
575 used to execute debug_print. Use the Debug menu to select the current
576 thread and try using debug_print again. Note that the debugger halts
577 execution (e.g., due to a breakpoint) in the context of the current
578 thread, so this should only be a problem if you've explicitly switched
579 threads.
4b994b84 580
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581\f
582This file is part of GNU Emacs.
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eef0be9e 584GNU Emacs is free software: you can redistribute it and/or modify
7f6d64f8 585it under the terms of the GNU General Public License as published by
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586the Free Software Foundation, either version 3 of the License, or
587(at your option) any later version.
4b994b84 588
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589GNU Emacs is distributed in the hope that it will be useful,
590but WITHOUT ANY WARRANTY; without even the implied warranty of
591MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
592GNU General Public License for more details.
593
594You should have received a copy of the GNU General Public License
eef0be9e 595along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.