nt/INSTALL

   1                     Building and Installing Emacs on MS-Windows
   2                           using the MSYS and MinGW tools
   3
   4   Copyright (C) 2013 Free Software Foundation, Inc.
   5   See the end of the file for license conditions.
   6
   7 The MSYS/MinGW build described here is supported on versions of
   8 Windows starting with Windows 2000 and newer.  Windows 9X are not
   9 supported (but the Emacs binary produced by this build will run on
  10 Windows 9X as well).
  11
  12 * For the brave (a.k.a. "impatient"):
  13
  14   For those who have a working MSYS/MinGW development environment and
  15   are comfortable with running Posix configure scripts, here are the
  16   concise instructions for configuring and building the native Windows
  17   binary of Emacs with these tools.
  18
  19   Do not use this recipe with Cygwin.  For building on Cygwin, use the
  20   normal installation instructions, ../INSTALL.
  21
  22   0. Start the MSYS Bash window.  Everything else below is done from
  23      that window's Bash prompt.
  24
  25   0a. If you are building from the development trunk (as opposed to a
  26       release tarball), produce the configure script, by typing from
  27       the top-level Emacs source directory:
  28
  29       ./autogen.sh
  30
  31   1. If you want to build Emacs outside of the source tree
  32      (recommended), create the build directory and chdir there.
  33
  34   2. Invoke the MSYS-specific configure script:
  35
  36       - If you are building outside the source tree:
  37
  38         /PATH/TO/EMACS/SOURCE/TREE/nt/msysconfig.sh --prefix=PREFIX ...
  39
  40       - If you are building in-place, i.e. inside the source tree:
  41
  42         ./nt/msysconfig.sh --prefix=PREFIX ...
  43
  44      It is always preferable to use --prefix to configure Emacs for
  45      some specific location of its installed tree; the default
  46      /usr/local is not suitable for Windows (see the detailed
  47      instructions for the reasons).
  48
  49      You can pass other options to the configure script.  Here's a
  50      typical example (for an in-place debug build):
  51
  52        CPPFLAGS='-DGLYPH_DEBUG=1' CFLAGS='-O0 -g3' ./nt/msysconfig.sh --prefix=/d/usr/emacs --enable-checking
  53
  54   3. After the configure script finishes, it should display the
  55      resulting configuration.  After that, type
  56
  57        make
  58
  59      Use "make -j N" if your MSYS Make supports parallel execution;
  60      the build will take significantly less time in that case.  Here N
  61      is the number of simultaneous parallel jobs; use the number of
  62      the cores on your system.
  63
  64   4. Install the produced binaries:
  65
  66        make install
  67
  68      If you want the installation tree to go to a place that is
  69      different from the one specified by --prefix, say
  70
  71        make install prefix=/where/ever/you/want
  72
  73   That's it!
  74
  75   If these short instructions somehow fail, read the rest of this
  76   file.
  77
  78 * Installing MinGW and MSYS
  79
  80   Make sure you carefully read the following two sections in their
  81   entirety and install/configure the various packages as instructed.
  82   A correct installation makes all the rest almost trivial; a botched
  83   installation will likely make you miserable for quite some time.
  84
  85   There are two alternative to installing MinGW + MSYS: using the GUI
  86   installer, called mingw-get, provided by the MinGW project, or
  87   manual installation.  The next two sections describe each one of
  88   these.
  89
  90 ** Installing MinGW and MSYS using mingw-get
  91
  92   A nice installer, called mingw-get, is available for those who don't
  93   like to mess with manual installations.  You can download it from
  94   here:
  95
  96     https://sourceforge.net/projects/mingw/files/Installer/mingw-get/
  97
  98   (This installer only supports packages downloaded from the MinGW
  99   site; for the rest you will still need the manual method.)
 100
 101   After installing mingw-get, invoke it to install the packages that
 102   are already selected by default on the "Select Components" screen of
 103   its wizard.
 104
 105   After that, use "mingw-get install PACKAGE" to install the following
 106   additional packages:
 107
 108    . msys-base
 109    . mingw-developer-toolkit
 110
 111   (We recommend that you refrain from installing the MSYS Texinfo
 112   package, which is part of msys-base, because it might produce mixed
 113   EOL format when installing Info files.  Instead, install the MinGW
 114   port of Texinfo, see the ezwinports URL below.  To uninstall the
 115   MSYS Texinfo, after installing it as part of msys-base, invoke the
 116   command "mingw-get remove msys-texinfo".)
 117
 118   At this point, you should be ready to configure and build Emacs in
 119   its basic configuration.  Skip to the "Generating the configure
 120   script" section for the build instructions.  If you want to build it
 121   with image support and other optional libraries, read about the
 122   optional libraries near the end of this document, before you start
 123   the build.  Also, consider installing additional MinGW packages that
 124   are required/recommended, especially if you are building from the
 125   Bazaar repository, as described in the next section.
 126
 127 ** Installing MinGW and MSYS manually
 128
 129 *** MinGW
 130
 131   You will need to install the MinGW port of GCC and Binutils, and the
 132   MinGW runtime and Windows API distributions, to compile Emacs.  You
 133   can find these on the MinGW download/Base page:
 134
 135     https://sourceforge.net/projects/mingw/files/MinGW/Base/
 136
 137   In general, install the latest stable versions of the following
 138   MinGW packages from that page: gcc, binutils, mingw-rt, w32api.  You
 139   only need the 'bin' and the 'dll' tarballs of each of the above.
 140
 141   MinGW packages are distributed as .tar.lzma compressed archives.  To
 142   install the packages manually, we recommend to use the Windows port
 143   of the 'bsdtar' program to unpack the tarballs.  'bsdtar' is
 144   available as part of the 'libarchive' package from here:
 145
 146     http://sourceforge.net/projects/ezwinports/files/
 147
 148   The recommended place to install these packages is a single tree
 149   starting from some directory on a drive other than the system drive
 150   C:.  A typical example would be D:\usr, with D:\usr\bin holding the
 151   binaries and DLLs (should be added to your Path environment
 152   variable), D:\usr\include holding the include files, D:\usr\lib
 153   holding the static and import libraries, D:\usr\share holding docs,
 154   message catalogs, and package-specific subdirectories, etc.
 155
 156   Having all the headers and libraries in a single place will greatly
 157   reduce the number of -I and -L flags you will have to pass to the
 158   configure script (see below), as these files will be right where the
 159   compiler expects them.
 160
 161   We specifically do NOT recommend installing packages below
 162   "C:\Program Files" or "C:\Program Files (x86)".  These directories
 163   are protected on versions of Windows from Vista and on, and you will
 164   have difficulties updating and maintaining your installation later,
 165   due to UAC elevation prompts, file virtualization, etc.  You *have*
 166   been warned!
 167
 168   Additional MinGW packages are required/recommended, especially if
 169   you are building from the Bazaar repository:
 170
 171    . Texinfo (needed to produce the Info manuals when building from
 172      bzr, and for "make install")
 173
 174      Available from http://sourceforge.net/projects/ezwinports/files/.
 175
 176    . gzip (needed to compress files during "make install")
 177
 178      Available from http://gnuwin32.sourceforge.net/packages/gzip.htm.
 179
 180    . pkg-config (needed for building with some optional libraries,
 181      such as GnuTLS and libxml2)
 182
 183      Available from http://www.gtk.org/download/win32.php
 184
 185   Each package might list other packages as prerequisites on its
 186   download page (under "Runtime requirements"); download those as
 187   well.  (Using the mingw-get installer will fetch those prerequisites
 188   automatically for you.)  A missing prerequisite will manifest itself
 189   by the program failing to run and presenting a pop-up dialog that
 190   states the missing or incompatible DLL; be sure to find and install
 191   these missing DLLs.
 192
 193   Once you think you have MinGW installed, test the installation by
 194   building a trivial "hello, world!" program, and make sure that it
 195   builds without any error messages and the binary works when run.
 196
 197 *** MSYS
 198
 199   You will need a reasonably full MSYS installation.  MSYS is an
 200   environment needed to run the Posix configure scripts and the
 201   resulting Makefile's, in order to produce native Windows binaries
 202   using the MinGW compiler and runtime libraries.  Here's the list of
 203   MSYS packages that are required:
 204
 205    . All the packages from the MSYS Base distribution, listed here:
 206
 207      https://sourceforge.net/projects/mingw/files/MSYS/Base/
 208
 209    . Additional packages listed below, from the MSYS Extension
 210      distribution here:
 211
 212      https://sourceforge.net/projects/mingw/files/MSYS/Extension/
 213
 214       - flex
 215       - bison
 216       - m4
 217       - perl
 218       - mktemp
 219
 220      These should only be needed if you intend to build development
 221      versions of Emacs from the Bazaar repository.
 222
 223    . Additional packages (needed only if building from the Bazaar
 224      repository): Automake and Autoconf.  They are available from
 225      here:
 226
 227        http://sourceforge.net/projects/ezwinports/files/automake-1.11.6-msys-bin.zip/download
 228        http://sourceforge.net/projects/ezwinports/files/autoconf-2.65-msys-bin.zip/download
 229
 230   MSYS packages are distributed as .tar.lzma compressed archives.  To
 231   install the packages manually, we recommend to use the Windows port
 232   of the 'bsdtar' program, already mentioned above.
 233
 234   If/when you are confident in your MinGW/MSYS installation, and want
 235   to speed up the builds, we recommend installing a pre-release
 236   version of Make from here:
 237
 238      https://sourceforge.net/projects/mingwbuilds/files/external-binary-packages/
 239
 240   These are snapshot builds of many packages, but you only need
 241   make.exe from there.  The advantage of this make.exe is that it
 242   supports parallel builds, so you can use "make -j N" to considerably
 243   speed up your builds.
 244
 245   Several users reported that MSYS 1.0.18 causes Make to hang in
 246   parallel builds.  If you bump into this, we suggest to downgrade to
 247   MSYS 1.0.17, which doesn't have that problem.
 248
 249   For each of these packages, install the 'bin' and 'dll' tarballs of
 250   their latest stable releases.  If there's an 'ext' tarball (e.g.,
 251   msysCORE and Coreutils have it), download and install those as well.
 252
 253   Each package might list other packages as prerequisites on its
 254   download page (under "Runtime requirements"); download those as
 255   well.  (Using the mingw-get installer will fetch those prerequisites
 256   automatically for you.)  A missing prerequisite will manifest itself
 257   by the program failing to run and presenting a pop-up dialog that
 258   states the missing or incompatible DLL; be sure to find and install
 259   these missing DLLs.
 260
 261   MSYS packages should be installed in a separate tree from MinGW.
 262   For example, use D:\MSYS or D:\usr\MSYS as the top-level directory
 263   from which you unpack all of the MSYS packages.
 264
 265   Do NOT add the MSYS bin directory to your Windows Path!  Only the
 266   MinGW bin directory should be on Path.  When you install MSYS, it
 267   creates a shortcut on your desktop that invokes the MSYS Bash shell
 268   in a Command Prompt window; that shell is already set up so that the
 269   MSYS bin directory is on PATH ahead of any other directory.  Thus,
 270   Bash will find MSYS executables first, which is exactly what you
 271   need.
 272
 273   At this point, you are ready to build Emacs in its basic
 274   configuration.  If you want to build it with image support and other
 275   optional libraries, read about that near the end of this document.
 276
 277 * Generating the configure script
 278
 279   If you are building a release or pretest tarball, skip this section,
 280   because the configure script is already present in the tarball.
 281
 282   To build a development snapshot from the Emacs Bazaar repository,
 283   you will first need to generate the configure script and a few other
 284   auto-generated files.  (If this step, described below, somehow
 285   fails, you can use the files in the autogen/ directory instead, but
 286   they might be outdated, and, most importantly, you are well advised
 287   not to disregard any failures in your local build procedures, as
 288   these are likely to be symptoms of incorrect installation that will
 289   bite you down the road.)
 290
 291   To generate the configure script, type this at the MSYS Bash prompt
 292   from the top-level directory of the Emacs tree:
 293
 294      ./autogen.sh
 295
 296   If successful, this command should produce the following output:
 297
 298      $ ./autogen.sh
 299      Checking whether you have the necessary tools...
 300      (Read INSTALL.BZR for more details on building Emacs)
 301
 302      Checking for autoconf (need at least version 2.65)...
 303      ok
 304      Checking for automake (need at least version 1.11)...
 305      ok
 306      Your system has the required tools, running autoreconf...
 307      You can now run `./configure'.
 308
 309 * Configuring Emacs for MinGW:
 310
 311   Now it's time to run the configure script.  You can do that either
 312   from a separate build directory that is outside of the Emacs source
 313   tree (recommended), or from inside the source tree.  The former is
 314   recommended because it allows you to have several different builds,
 315   e.g., an optimized build and an unoptimized one, of the same
 316   revision of the source tree; the source tree will be left in its
 317   pristine state, without any build products.
 318
 319   You invoke the configure script like this:
 320
 321      /PATH/TO/EMACS/SOURCE/TREE/nt/msysconfig.sh --prefix=PREFIX ...
 322
 323   or, if you are building in-place, i.e. inside the source tree:
 324
 325      ./nt/msysconfig.sh --prefix=PREFIX ...
 326
 327   Here PREFIX is the place where you eventually want to install Emacs
 328   once built, e.g. /d/usr.  We recommend to always use --prefix when
 329   building Emacs on Windows, because the default '/usr/local' is not
 330   appropriate for Windows: it will be mapped by MSYS to something like
 331   C:\MSYS\local, and it will defeat the purpose of PREFIX, which is to
 332   install programs in a single coherent tree resembling Posix systems.
 333   Such a single-tree installation makes sure all the other programs
 334   and packages ported from GNU or Unix systems will work seamlessly
 335   together.  Where exactly is the root of that tree on your system is
 336   something only you, the user who builds Emacs, can know, and the
 337   Emacs build process cannot guess, because usually there's no
 338   '/usr/local' directory on any drive on Windows systems.
 339
 340   Do NOT use Windows-style x:/foo/bar file names on the configure
 341   script command line; use the MSYS-style /x/foo/bar instead.  Using
 342   Windows-style file names was reported to cause subtle and hard to
 343   figure out problems during the build.  This applies both to the
 344   command switches, such as --prefix=, and to the absolute file name
 345   of msysconfig.sh, if you are building outside of the source tree.
 346
 347   You can pass additional options to the configure script, for the
 348   full list type
 349
 350      ./nt/msysconfig.sh --help
 351
 352   As explained in the help text, you may need to tell the script what
 353   are the optional flags to invoke the compiler.  This is needed if
 354   some of your headers and libraries, e.g., those belonging to
 355   optional image libraries, are installed in places where the compiler
 356   normally doesn't look for them.  (Remember that advice above to
 357   avoid such situations? here's is where you will start paying for
 358   disregarding that recommendation.)  For example, if you have libpng
 359   headers in C:\emacs\libs\libpng-1.2.37-lib\include and jpeg library
 360   headers in C:\emacs\libs\jpeg-6b-4-lib\include, you will need to say
 361   something like this:
 362
 363     CPPFLAGS='-I/c/emacs/libs/libpng-1.2.37-lib/include -I/c/emacs/libs/jpeg-6b-4-lib/include' ./nt/msysconfig.sh --prefix=PREFIX
 364
 365   which is quite a mouth-full, especially if you have more directories
 366   to specify...  Perhaps you may wish to revisit your installation
 367   decisions now.
 368
 369   If you have a global site-lisp directory from previous Emacs
 370   installation, and you want Emacs to continue using it, specify it
 371   via the --enable-locallisppath switch to msysconfig.sh, like this:
 372
 373    ./nt/msysconfig.sh --prefix=PREFIX --enable-locallisppath="/d/usr/share/emacs/VERSION/site-lisp:/d/wherever/site-lisp"
 374
 375   Use the normal MSYS /d/foo/bar style to specify directories by their
 376   absolute file names.
 377
 378   A few frequently used options are needed when you want to produce an
 379   unoptimized binary with runtime checks enabled:
 380
 381      CPPFLAGS='-DGLYPH_DEBUG=1' CFLAGS='-O0 -g3' ./nt/msysconfig.sh --prefix=PREFIX --enable-checking
 382
 383   Once invoked, the configure script will run for some time, and, if
 384   successful, will eventually produce a summary of the configuration
 385   like this:
 386
 387      Configured for `i686-pc-mingw32'.
 388
 389        Where should the build process find the source code?    /path/to/emacs/sources
 390        What compiler should emacs be built with?               gcc  -std=gnu99 -O0 -g3
 391        Should Emacs use the GNU version of malloc?             yes
 392        Should Emacs use a relocating allocator for buffers?    yes
 393        Should Emacs use mmap(2) for buffer allocation?         no
 394        What window system should Emacs use?                    w32
 395        What toolkit should Emacs use?                          none
 396        Where do we find X Windows header files?                NONE
 397        Where do we find X Windows libraries?                   NONE
 398        Does Emacs use -lXaw3d?                                 no
 399        Does Emacs use -lXpm?                                   yes
 400        Does Emacs use -ljpeg?                                  yes
 401        Does Emacs use -ltiff?                                  yes
 402        Does Emacs use a gif library?                           yes
 403        Does Emacs use -lpng?                                   yes
 404        Does Emacs use -lrsvg-2?                                no
 405        Does Emacs use imagemagick?                             no
 406        Does Emacs use -lgpm?                                   no
 407        Does Emacs use -ldbus?                                  no
 408        Does Emacs use -lgconf?                                 no
 409        Does Emacs use GSettings?                               no
 410        Does Emacs use -lselinux?                               no
 411        Does Emacs use -lgnutls?                                yes
 412        Does Emacs use -lxml2?                                  yes
 413        Does Emacs use -lfreetype?                              no
 414        Does Emacs use -lm17n-flt?                              no
 415        Does Emacs use -lotf?                                   no
 416        Does Emacs use -lxft?                                   no
 417        Does Emacs use toolkit scroll bars?                     yes
 418
 419   You are almost there, hang on.
 420
 421   If the output is significantly different, or if configure finishes
 422   prematurely and displays some error message, you should examine the
 423   configuration log in config.log and find the reason for the failure.
 424
 425   Once you succeeded in configuring Emacs, and just want to rebuild it
 426   after updating your local repository from the main repository, you
 427   don't need to re-run the configure script manually, unless you want
 428   to change the configure-time options.  Just typing "make" will
 429   re-run configure if necessary with the exact same options you
 430   specified originally, and then go on to invoking Make, described
 431   below.
 432
 433 * Running Make.
 434
 435   This is simple: just type "make" and sit back, watching the fun.
 436
 437   If you  installed a snapshot build  of Make, the build  will be much
 438   faster if  you type "make  -j N" instead, where  N is the  number of
 439   independent processing  units on your  machine.  E.g., on a  core i7
 440   system try using  N of 6 or  even 8.  (If this hangs,  see the notes
 441   above about downgrading to MSYS 1.0.17.)
 442
 443   When Make finishes, you can install the produced binaries:
 444
 445     make install
 446
 447   or, if you want the installed tree to go in a place different from
 448   the configured one, type
 449
 450     make install prefix=WHEREVER
 451
 452   Congrats!  You have built and installed your own Emacs!
 453
 454 * Make targets
 455
 456   The following make targets may be used by users building the source
 457   distribution, or users who have checked out of Bazaar after
 458   an initial bootstrapping.
 459
 460   make
 461   Builds Emacs from the available sources and pre-compiled lisp files.
 462
 463   make install
 464   Installs the built programs and the auxiliary files.
 465
 466   make clean
 467   Removes object and executable files produced by the build process in
 468   the current configuration.  After "make clean", you can rebuild with
 469   the same configuration using make.  useful when you want to be sure
 470   that all of the products are built from coherent sources.
 471
 472   make distclean
 473   In addition to the files removed by make clean, this also removes
 474   Makefiles and other generated files to get back to the state of a
 475   freshly unpacked source distribution.  After make distclean, it is
 476   necessary to run the configure script followed by "make", in order
 477   to rebuild.
 478
 479   The following targets are intended only for use with the Bazaar sources.
 480
 481   make bootstrap
 482   Removes all the auto-generated files and all the *.elc byte-compiled
 483   files, and builds Emacs from scratch.  Useful when some change in
 484   basic Emacs functionality makes byte compilation of updated files
 485   fail.
 486
 487   make maintainer-clean
 488   Removes everything that can be recreated, including compiled Lisp
 489   files, to get back to the state of a fresh Bazaar tree.  After make
 490   maintainer-clean, it is necessary to run configure and "make" or
 491   "make bootstrap" to rebuild.  Occasionally it may be necessary to
 492   run this target after an update.
 493
 494 * Optional image library support
 495
 496   In addition to its "native" image formats (pbm and xbm), Emacs can
 497   handle other image types: xpm, tiff, gif, png, jpeg and experimental
 498   support for svg.
 499
 500   To build Emacs with support for them, the corresponding headers must
 501   be in the include path and libraries should be where the linker
 502   looks for them, when the configure script is run.  If needed, this
 503   can be set up using the CPPFLAGS and CFLAGS variable specified on
 504   the configure command line.  The configure script will report
 505   whether it was able to detect the headers and libraries.  If the
 506   results of this testing appear to be incorrect, please look for
 507   details in the file config.log: it will show the failed test
 508   programs and compiler error messages that should explain what is
 509   wrong.  (Usually, any such failures happen because some headers are
 510   missing due to bad packaging of the image support libraries.)
 511
 512   Note that any file path passed to the compiler or linker must use
 513   forward slashes, or double each backslash, as that is how Bash
 514   works.
 515
 516   If the configure script finds the necessary headers and libraries,
 517   but they are for some reason incompatible, or if you want to omit
 518   support for some image library that is installed on your system for
 519   some other reason, use the --without-PACKAGE option to configure,
 520   such as --without-gif to omit GIF, --without-tiff to omit TIFF, etc.
 521   Passing the --help option to the configure script displays all of
 522   the supported --without-PACKAGE options.
 523
 524   To use the external image support, the DLLs implementing the
 525   functionality must be found when Emacs first needs them, either on the
 526   PATH, or in the same directory as emacs.exe.  Failure to find a
 527   library is not an error; the associated image format will simply be
 528   unavailable.  Note that once Emacs has determined that a library can
 529   not be found, there's no way to force it to try again, other than
 530   restarting.  See the variable `dynamic-library-alist' to configure the
 531   expected names of the libraries.
 532
 533   Some image libraries have dependencies on one another, or on zlib.
 534   For example, tiff support depends on the jpeg library.  If you did not
 535   compile the libraries yourself, you must make sure that any dependency
 536   is in the PATH or otherwise accessible and that the binaries are
 537   compatible (for example, that they were built with the same compiler).
 538
 539   For PNG images, we recommend to use versions 1.4.x and later of
 540   libpng, because previous versions had security issues.  You can find
 541   precompiled libraries and headers on the GTK download page for
 542   Windows (http://www.gtk.org/download/win32.php).
 543
 544   Versions 1.4.0 and later of libpng are binary incompatible with
 545   earlier versions, so Emacs will only look for libpng libraries which
 546   are compatible with the version it was compiled against.  That
 547   version is given by the value of the Lisp variable `libpng-version';
 548   e.g., 10403 means version 1.4.3.  The variable `dynamic-library-alist'
 549   is automatically set to name only those DLL names that are known to
 550   be compatible with the version given by `libpng-version'.  If PNG
 551   support does not work for you even though you have the support DLL
 552   installed, check the name of the installed DLL against
 553   `dynamic-library-alist' and the value of `libpng-version', and
 554   download compatible DLLs if needed.
 555
 556   For GIF images, we recommend to use versions 5.0.0 or later of
 557   giflib, as it is much enhanced wrt previous versions.  You can find
 558   precompiled binaries and headers for giflib on the ezwinports site,
 559   http://sourceforge.net/projects/ezwinports/files/.
 560
 561   Version 5.0.0 and later of giflib are binary incompatible with
 562   previous versions (the signatures of several functions have
 563   changed), so Emacs will only look for giflib libraries that are
 564   compatible with the version it was compiled against.  Similar to
 565   libpng, that version is given by the value of the Lisp variable
 566   `libgif-version'; e.g., 50005 means version 5.0.5.  The variable
 567   `dynamic-library-alist' is automatically set to name only those DLL
 568   libraries that are known to be compatible with the version given by
 569   `libgif-version'.
 570
 571   Binaries for the other image libraries can be found at the GnuWin32
 572   project.  Note specifically that, due to some packaging snafus in
 573   the GnuWin32-supplied image libraries, you will need to download
 574   _source_ packages for some of the libraries in order to get the
 575   header files necessary for building Emacs with image support.
 576
 577 * Optional GnuTLS support
 578
 579   To compile with GnuTLS, you will need pkg-config to be installed, as
 580   the configure script invokes pkg-config to find out which compiler
 581   switches to use for GnuTLS.  See above for the URL where you can
 582   find pkg-config for Windows.
 583
 584   You will also need to install the p11-kit package, which is a
 585   dependency of GnuTLS, and its header files are needed for
 586   compilation of programs that use GnuTLS.  You can find p11-kit on
 587   the same site as GnuTLS, see the URL below.
 588
 589   If the configure script finds the GnuTLS header files and libraries
 590   on your system, Emacs is built with GnuTLS support by default; to
 591   avoid that you can pass the argument --without-gnutls.
 592
 593   In order to support GnuTLS at runtime, a GnuTLS-enabled Emacs must
 594   be able to find the relevant DLLs during startup; failure to do so
 595   is not an error, but GnuTLS won't be available to the running
 596   session.
 597
 598   You can get pre-built binaries (including any required DLL and the
 599   header files) at http://sourceforge.net/projects/ezwinports/files/.
 600
 601 * Optional libxml2 support
 602
 603   To compile with libxml2, you will need pkg-config to be installed,
 604   as the configure script invokes pkg-config to find out which
 605   compiler switches to use for libxml2.  See above for the URL where
 606   you can find pkg-config for Windows.
 607
 608   If the configure script finds the libxml2 header files and libraries
 609   on your system, Emacs is built with libxml2 support by default; to
 610   avoid that you can pass the argument --without-libxml2.
 611
 612   In order to support libxml2 at runtime, a libxml2-enabled Emacs must
 613   be able to find the relevant DLLs during startup; failure to do so
 614   is not an error, but libxml2 features won't be available to the
 615   running session.
 616
 617   One place where you can get pre-built Windows binaries of libxml2
 618   (including any required DLL and the header files) is here:
 619
 620      http://sourceforge.net/projects/ezwinports/files/
 621
 622   For runtime support of libxml2, you will also need to install the
 623   libiconv "development" tarball, because the libiconv headers need to
 624   be available to the compiler when you compile with libxml2 support.
 625   A MinGW port of libiconv can be found on the MinGW site:
 626
 627    http://sourceforge.net/projects/mingw/files/MinGW/Base/libiconv/
 628
 629   You need the libiconv-X.Y.Z-N-mingw32-dev.tar.lzma tarball from that
 630   site.
 631
 632 * Experimental SVG support
 633
 634   To compile with SVG, you will need pkg-config to be installed, as
 635   the configure script invokes pkg-config to find out which compiler
 636   switches to use for SVG.  See above for the URL where you can find
 637   pkg-config for Windows.
 638
 639   SVG support is currently experimental, and not built by default.
 640   Specify --with-rsvg and ensure you have all the dependencies in your
 641   include path.  Unless you have built a minimalist librsvg yourself
 642   (untested), librsvg depends on a significant chunk of GTK+ to build,
 643   plus a few Gnome libraries, libxml2, libbz2 and zlib at runtime.  The
 644   easiest way to obtain the dependencies required for building is to
 645   download a pre-bundled GTK+ development environment for Windows.
 646
 647   To use librsvg at runtime, ensure that librsvg and its dependencies
 648   are on your PATH.  If you didn't build librsvg yourself, you will
 649   need to check with where you downloaded it from for the
 650   dependencies, as there are different build options.  If it is a
 651   short list, then it most likely only lists the immediate
 652   dependencies of librsvg, but the dependencies themselves have
 653   dependencies - so don't download individual libraries from GTK+,
 654   download and install the whole thing.  If you think you've got all
 655   the dependencies and SVG support is still not working, check your
 656   PATH for other libraries that shadow the ones you downloaded.
 657   Libraries of the same name from different sources may not be
 658   compatible, this problem was encountered with libbzip2 from GnuWin32
 659   with libcroco from gnome.org.
 660
 661   If you can see etc/images/splash.svg, then you have managed to get
 662   SVG support working.  Congratulations for making it through DLL hell
 663   to this point.  You'll probably find that some SVG images crash
 664   Emacs.  Problems have been observed in some images that contain
 665   text, they seem to be a problem in the Windows port of Pango, or
 666   maybe a problem with the way Cairo or librsvg is using it that
 667   doesn't show up on other platforms.
 668
 669 \f
 670 This file is part of GNU Emacs.
 671
 672 GNU Emacs is free software: you can redistribute it and/or modify
 673 it under the terms of the GNU General Public License as published by
 674 the Free Software Foundation, either version 3 of the License, or
 675 (at your option) any later version.
 676
 677 GNU Emacs is distributed in the hope that it will be useful,
 678 but WITHOUT ANY WARRANTY; without even the implied warranty of
 679 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 680 GNU General Public License for more details.
 681
 682 You should have received a copy of the GNU General Public License
 683 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.