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1 Building and Installing Emacs on Windows
2 (from 95 to 7 and beyond)
3
4 Copyright (C) 2001-2011 Free Software Foundation, Inc.
5 See the end of the file for license conditions.
6
7 * For the impatient
8
9 Here are the concise instructions for configuring and building the
10 native Windows binary of Emacs, for those who want to skip the
11 complex explanations and ``just do it'':
12
13 Do not use this recipe with Cygwin. For building on Cygwin,
14 use the normal installation instructions, ../INSTALL.
15
16 1. Change to the `nt' directory (the directory of this file):
17
18 cd nt
19
20 2. Run configure.bat. From the COMMAND.COM/CMD.EXE command prompt:
21
22 configure
23
24 from a Unixy shell prompt:
25
26 cmd /c configure.bat
27 or
28 command.com /c configure.bat
29
30 3. Run the Make utility suitable for your environment. If you build
31 with the Microsoft's Visual C compiler (but see notes about using
32 VC++ 8.0 and later below):
33
34 nmake
35
36 For the development environments based on GNU GCC (MinGW, MSYS,
37 Cygwin - but see notes about Cygwin make below), depending on how
38 Make is called, it could be:
39
40 make
41 or
42 mingw32-make
43 or
44 gnumake
45 or
46 gmake
47
48 (If you are building from Bazaar, say "make bootstrap" or "nmake
49 bootstrap" instead, and avoid using Cygwin make.)
50
51 With GNU Make, you can use the -j command-line option to have
52 Make execute several commands at once, like this:
53
54 gmake -j 2 XMFLAGS="-j 2"
55
56 The XMFLAGS variable overrides the default behavior of GNU Make
57 on Windows, whereby recursive Make invocations reset the maximum
58 number of simultaneous commands to 1. The above command allows
59 up to 4 simultaneous commands at once in the top-level Make, and
60 up to 3 in each one of the recursive Make's.
61
62 4. Generate the Info manuals (only if you are building out of Bazaar,
63 and if you have makeinfo.exe installed):
64
65 make info
66
67 (change "make" to "nmake" if you use MSVC).
68
69 5. Install the produced binaries:
70
71 make install
72
73 That's it!
74
75 If these short instructions somehow fail, read the rest of this
76 file.
77
78 * Preliminaries
79
80 If you want to build a Cygwin port of Emacs, use the instructions in
81 the INSTALL file in the main Emacs directory (the parent of this
82 directory). These instructions are for building a native Windows
83 binary of Emacs.
84
85 If you used WinZip to unpack the distribution, we suggest to
86 remove the files and unpack again with a different program!
87 WinZip is known to create some subtle and hard to debug problems,
88 such as converting files to DOS CR-LF format, not creating empty
89 directories, etc. We suggest to use djtarnt.exe from the GNU FTP
90 site.
91
92 In addition to this file, you should also read INSTALL.BZR in the
93 parent directory, and make sure that you have a version of
94 "touch.exe" in your path, and that it will create files that do not
95 yet exist.
96
97 * Supported development environments
98
99 To compile Emacs, you will need either Microsoft Visual C++ 2.0, or
100 later up to 7.0, and nmake, or a Windows port of GCC 2.95 or later
101 with MinGW and W32 API support and a port of GNU Make. You can use
102 the Cygwin ports of GCC, but Emacs requires the MinGW headers and
103 libraries to build (latest versions of the Cygwin toolkit, at least
104 since v1.3.3, include the MinGW headers and libraries as an integral
105 part).
106
107 Note that building Emacs with Visual Studio 2005 (VC++ 8.0) and
108 later is not supported at this time, due to changes introduced by
109 Microsoft into the libraries shipped with the compiler.
110
111 The rest of this file assumes you have a working development
112 environment. If you just installed such an environment, try
113 building a trivial C "Hello world" program, and see if it works. If
114 it doesn't work, resolve that problem first! If you use Microsoft
115 Visual Studio .NET 2003, don't forget to run the VCVARS32.BAT batch
116 file from the `Bin' subdirectory of the directory where you have
117 installed VS.NET.
118
119 If you use the MinGW port of GCC and GNU Make to build Emacs, there
120 are some compatibility issues wrt Make and the shell that is run by
121 Make, either the standard COMMAND.COM/CMD.EXE supplied with Windows
122 or sh.exe, a port of a Unixy shell. For reference, below is a list
123 of which builds of GNU Make are known to work or not, and whether
124 they work in the presence and/or absence of sh.exe, the Cygwin port
125 of Bash. Note that any version of Make that is compiled with Cygwin
126 will only work with Cygwin tools, due to the use of Cygwin style
127 paths. This means Cygwin Make is unsuitable for building parts of
128 Emacs that need to invoke Emacs itself (leim and "make bootstrap",
129 for example). Also see the Trouble-shooting section below if you
130 decide to go ahead and use Cygwin make.
131
132 In addition, using 4NT or TCC as your shell is known to fail the build
133 process, at least since 4NT version 3.01. Use CMD.EXE, the default
134 Windows shell, instead. MSYS sh.exe also appears to cause various
135 problems. If you have MSYS installed, try "make SHELL=cmd.exe" to
136 force the use of cmd.exe instead of sh.exe.
137
138 sh exists no sh
139
140 cygwin b20.1 make (3.75): fails[1, 5] fails[2, 5]
141 MSVC compiled gmake 3.77: okay okay
142 MSVC compiled gmake 3.78.1: okay okay
143 MSVC compiled gmake 3.79.1: okay okay
144 mingw32/gcc-2.92.2 make (3.77): okay okay[4]
145 cygwin compiled gmake 3.77: fails[1, 5] fails[2, 5]
146 cygwin compiled make 3.78.1: fails[5] fails[2, 5]
147 cygwin compiled make 3.79.1: fails[3, 5] fails[2?, 5]
148 cygwin compiled make 3.80: okay[6] fails?[7]
149 cygwin compiled make 3.81: fails fails?[7]
150 mingw32 compiled make 3.79.1: okay okay
151 mingw32 compiled make 3.80: okay okay[7]
152 mingw32 compiled make 3.81: okay okay[8]
153
154 Notes:
155
156 [1] doesn't cope with makefiles with DOS line endings, so must mount
157 emacs source with text!=binary.
158 [2] fails when needs to invoke shell commands; okay invoking gcc etc.
159 [3] requires LC_MESSAGES support to build; cannot build with early
160 versions of Cygwin.
161 [4] may fail on Windows 9X and Windows ME; if so, install Bash.
162 [5] fails when building leim due to the use of cygwin style paths.
163 May work if building emacs without leim.
164 [6] need to uncomment 3 lines in nt/gmake.defs that invoke `cygpath'
165 (look for "cygpath" near line 85 of gmake.defs).
166 [7] not recommended; please report if you try this combination.
167 [8] tested only on Windows XP.
168
169 Other compilers may work, but specific reports from people that have
170 tried suggest that the Intel C compiler (for example) may produce an
171 Emacs executable with strange filename completion behavior. Unless
172 you would like to assist by finding and fixing the cause of any bugs
173 like this, we recommend the use of the supported compilers mentioned
174 in the previous paragraph.
175
176 You will also need a copy of the POSIX cp, rm and mv programs. These
177 and other useful POSIX utilities can be obtained from one of several
178 projects:
179
180 * http://gnuwin32.sourceforge.net/ ( GnuWin32 )
181 * http://www.mingw.org/ ( MinGW )
182 * http://www.cygwin.com/ ( Cygwin )
183 * http://unxutils.sourceforge.net/ ( UnxUtils )
184
185 If you build Emacs on 16-bit versions of Windows (9X or ME), we
186 suggest to install the Cygwin port of Bash. That is because the
187 native Windows shell COMMAND.COM is too limited; the Emacs build
188 procedure tries very hard to support even such limited shells, but
189 as none of the Windows developers of Emacs work on Windows 9X, we
190 cannot guarantee that it works without a more powerful shell.
191
192 Additional instructions and help for building Emacs on Windows can be
193 found at the Emacs Wiki:
194
195 http://www.emacswiki.org/cgi-bin/wiki/WThirtyTwoInstallationKit
196
197 and on these URLs:
198
199 http://ourcomments.org/Emacs/w32-build-emacs.html
200 http://derekslager.com/blog/posts/2007/01/emacs-hack-3-compile-emacs-from-cvs-on-windows.ashx
201
202 Both of those pages were written before Emacs switched from CVS to
203 Bazaar, but the parts about building Emacs still apply in Bazaar.
204 The second URL has instructions for building with MSVC, as well as
205 with MinGW, while the first URL covers only MinGW, but has more
206 details about it.
207
208 * Configuring
209
210 Configuration of Emacs is now handled by running configure.bat in the
211 `nt' subdirectory. It will detect which compiler you have available,
212 and generate makefiles accordingly. You can override the compiler
213 detection, and control optimization and debug settings, by specifying
214 options on the command line when invoking configure.
215
216 To configure Emacs to build with GCC or MSVC, whichever is available,
217 simply change to the `nt' subdirectory and run `configure.bat' with no
218 options. To see what options are available, run `configure --help'.
219 Do NOT use the --no-debug option to configure.bat unless you are
220 absolutely sure the produced binaries will never need to be run under
221 a debugger.
222
223 Because of limitations of the stock Windows command shell, certain
224 characters (quotes, backslashes and equal signs) can be problematic
225 and should not be used in arguments to configure. That means that
226 forward slashes must be used in paths passed to the compiler and
227 linker via the --cflags and --ldflags options, and that it is
228 currently not possible to pass a macro like -DFOO=BAR (though -DFOO
229 is perfectly valid).
230
231 N.B. It is normal to see a few error messages output while configure
232 is running, when gcc support is being tested. These cannot be
233 suppressed because of limitations in the Windows 9X command.com shell.
234
235 You are encouraged to look at the file config.log which shows details
236 for failed tests, after configure.bat finishes. Any unexplained failure
237 should be investigated and perhaps reported as a bug (see the section
238 about reporting bugs in the file README in this directory and in the
239 Emacs manual).
240
241 * Optional image library support
242
243 In addition to its "native" image formats (pbm and xbm), Emacs can
244 handle other image types: xpm, tiff, gif, png, jpeg and experimental
245 support for svg.
246
247 To build Emacs with support for them, the corresponding headers must
248 be in the include path when the configure script is run. This can
249 be setup using environment variables, or by specifying --cflags
250 -I... options on the command-line to configure.bat. The configure
251 script will report whether it was able to detect the headers. If
252 the results of this testing appear to be incorrect, please look for
253 details in the file config.log: it will show the failed test
254 programs and compiler error messages that should explain what is
255 wrong. (Usually, any such failures happen because some headers are
256 missing due to bad packaging of the image support libraries.)
257
258 Note that any file path passed to the compiler or linker must use
259 forward slashes; using backslashes will cause compiler warnings or
260 errors about unrecognized escape sequences.
261
262 To use the external image support, the DLLs implementing the
263 functionality must be found when Emacs first needs them, either on the
264 PATH, or in the same directory as emacs.exe. Failure to find a
265 library is not an error; the associated image format will simply be
266 unavailable. Note that once Emacs has determined that a library can
267 not be found, there's no way to force it to try again, other than
268 restarting. See the variable `dynamic-library-alist' to configure the
269 expected names of the libraries.
270
271 Some image libraries have dependencies on one another, or on zlib.
272 For example, tiff support depends on the jpeg library. If you did not
273 compile the libraries yourself, you must make sure that any dependency
274 is in the PATH or otherwise accessible and that the binaries are
275 compatible (for example, that they were built with the same compiler).
276
277 Binaries for the image libraries (among many others) can be found at
278 the GnuWin32 project. PNG, JPEG and TIFF libraries are also
279 included with GTK, which is installed along with other Free Software
280 that requires it. These are built with MinGW, but they can be used
281 with both GCC/MinGW and MSVC builds of Emacs. See the info on
282 http://ourcomments.org/Emacs/w32-build-emacs.html, under "How to Get
283 Images Support", for more details about installing image support
284 libraries. Note specifically that, due to some packaging snafus in
285 the GnuWin32-supplied image libraries, you will need to download
286 _source_ packages for some of the libraries in order to get the
287 header files necessary for building Emacs with image support.
288
289 If GTK 2.0 is installed, addpm will arrange for its image libraries
290 to be on the DLL search path for Emacs.
291
292 For PNG images, we recommend to use versions 1.4.x and later of
293 libpng, because previous versions had security issues. You can find
294 precompiled libraries and headers on the GTK download page for
295 Windows (http://www.gtk.org/download-windows.html).
296
297 Versions 1.4.0 and later of libpng are binary incompatible with
298 earlier versions, so Emacs will only look for libpng libraries which
299 are compatible with the version it was compiled against. That
300 version is given by the value of the Lisp variable `libpng-version';
301 e.g., 10403 means version 1.4.3. The variable `dynamic-library-alist'
302 is automatically set to name only those DLL names that are known to
303 be compatible with the version given by `libpng-version'. If PNG
304 support does not work for you even though you have the support DLL
305 installed, check the name of the installed DLL against
306 `dynamic-library-alist' and the value of `libpng-version', and
307 download compatible DLLs if needed.
308
309 * Experimental SVG support
310
311 SVG support is currently experimental, and not built by default.
312 Specify --with-svg and ensure you have all the dependencies in your
313 include path. Unless you have built a minimalist librsvg yourself
314 (untested), librsvg depends on a significant chunk of GTK+ to build,
315 plus a few Gnome libraries, libxml2, libbz2 and zlib at runtime. The
316 easiest way to obtain the dependencies required for building is to
317 download a pre-bundled GTK+ development environment for Windows.
318 GTK puts its header files all over the place, so you will need to
319 run pkgconfig to list the include path you will need (either passed
320 to configure.bat as --cflags options, or set in the environment).
321
322 To use librsvg at runtime, ensure that librsvg and its dependencies
323 are on your PATH. If you didn't build librsvg yourself, you will
324 need to check with where you downloaded it from for the
325 dependencies, as there are different build options. If it is a
326 short list, then it most likely only lists the immediate
327 dependencies of librsvg, but the dependencies themselves have
328 dependencies - so don't download individual libraries from GTK+,
329 download and install the whole thing. If you think you've got all
330 the dependencies and SVG support is still not working, check your
331 PATH for other libraries that shadow the ones you downloaded.
332 Libraries of the same name from different sources may not be
333 compatible, this problem was encountered with libbzip2 from GnuWin32
334 with libcroco from gnome.org.
335
336 If you can see etc/images/splash.svg, then you have managed to get
337 SVG support working. Congratulations for making it through DLL hell
338 to this point. You'll probably find that some SVG images crash
339 Emacs. Problems have been observed in some images that contain
340 text, they seem to be a problem in the Windows port of Pango, or
341 maybe a problem with the way Cairo or librsvg is using it that
342 doesn't show up on other platforms.
343
344 * Building
345
346 After running configure, simply run the appropriate `make' program for
347 your compiler to build Emacs. For MSVC, this is nmake; for GCC, it is
348 GNU make. (If you are building out of Bazaar, say "make bootstrap" or
349 "nmake bootstrap" instead.)
350
351 As the files are compiled, you will see some warning messages
352 declaring that some functions don't return a value, or that some data
353 conversions will be lossy, etc. You can safely ignore these messages.
354 The warnings may be fixed in the main FSF source at some point, but
355 until then we will just live with them.
356
357 With GNU Make, you can use the -j command-line option to have Make
358 execute several commands at once, like this:
359
360 gmake -j 4 XMFLAGS="-j 3"
361
362 The XMFLAGS variable overrides the default behavior of GNU Make on
363 Windows, whereby recursive Make invocations reset the maximum number
364 of simultaneous commands to 1. The above command allows up to 4
365 simultaneous commands at once in the top-level Make, and up to 3 in
366 each one of the recursive Make's; you can use other numbers of jobs,
367 if you wish.
368
369 If you are building from Bazaar, the following commands will produce
370 the Info manuals (which are not part of the Bazaar sources):
371
372 make info
373 or
374 nmake info
375
376 Note that you will need makeinfo.exe (from the GNU Texinfo package)
377 in order for this command to succeed.
378
379 * Installing
380
381 To install Emacs after it has compiled, simply run `nmake install'
382 or `make install', depending on which version of the Make utility
383 do you have.
384
385 By default, Emacs will be installed in the location where it was
386 built, but a different location can be specified either using the
387 --prefix option to configure, or by setting INSTALL_DIR when running
388 make, like so:
389
390 make install INSTALL_DIR=D:/emacs
391
392 (for `nmake', type "nmake install INSTALL_DIR=D:/emacs" instead).
393
394 The install process will run addpm to setup the registry entries, and
395 to create a Start menu icon for Emacs.
396
397 * Make targets
398
399 The following make targets may be used by users building the source
400 distribution, or users who have checked out of Bazaar after
401 an initial bootstrapping.
402
403 make
404 Builds Emacs from the available sources and pre-compiled lisp files.
405
406 make install
407 Installs programs to the bin directory, and runs addpm to create
408 Start Menu icons.
409
410 make clean
411 Removes object and executable files produced by the build process in
412 the current configuration. After make clean, you can rebuild with
413 the same configuration using make.
414
415 make distclean
416 In addition to the files removed by make clean, this also removes
417 Makefiles and other generated files to get back to the state of a
418 freshly unpacked source distribution. Note that this will not remove
419 installed files, or the results of builds performed with different
420 compiler or optimization options than the current configuration.
421 After make distclean, it is necessary to run configure.bat followed
422 by make to rebuild.
423
424 make cleanall
425 Removes object and executable files that may have been created by
426 previous builds with different configure options, in addition to
427 the files produced by the current configuration.
428
429 make realclean
430 Removes the installed files in the bin subdirectory in addition to
431 the files removed by make cleanall.
432
433 make dist
434 Builds Emacs from the available sources and pre-compiled lisp files.
435 Packages Emacs binaries as full distribution and barebin distribution.
436
437 The following targets are intended only for use with the Bazaar sources.
438
439 make bootstrap
440 Creates a temporary emacs binary with lisp source files and
441 uses it to compile the lisp files. Once the lisp files are built,
442 emacs is redumped with the compiled lisp.
443
444 make recompile
445 Recompiles any changed lisp files after an update. This saves
446 doing a full bootstrap after every update. If this or a subsequent
447 make fail, you probably need to perform a full bootstrap, though
448 running this target multiple times may eventually sort out the
449 interdependencies.
450
451 make maintainer-clean
452 Removes everything that can be recreated, including compiled lisp
453 files, to get back to the state of a fresh Bazaar tree. After make
454 maintainer-clean, it is necessary to run configure.bat and make
455 bootstrap to rebuild. Occasionally it may be necessary to run this
456 target after an update.
457
458 * Creating binary distributions
459
460 Binary distributions (full and barebin distributions) can be
461 automatically built and packaged from source tarballs or a bzr
462 checkout.
463
464 When building Emacs binary distributions, the --distfiles argument
465 to configure.bat specifies files to be included in the bin directory
466 of the binary distributions. This is intended for libraries that are
467 not built as part of Emacs, e.g. image libraries.
468
469 For example, specifying
470
471 --distfiles D:\distfiles\libXpm.dll
472
473 results in libXpm.dll being copied from D:\distfiles to the
474 bin directory before packaging starts.
475
476 Multiple files can be specified using multiple --distfiles arguments:
477
478 --distfiles D:\distfiles\libXpm.dll --distfiles C:\jpeglib\jpeg.dll
479
480 For packaging the binary distributions, the 'dist' make target uses
481 7-Zip (http://www.7-zip.org), which must be installed and available
482 on the Windows Path.
483
484
485 * Trouble-shooting
486
487 The main problems that are likely to be encountered when building
488 Emacs stem from using an old version of GCC, or old MinGW or W32 API
489 headers. Additionally, Cygwin ports of GNU make may require the Emacs
490 source tree to be mounted with text!=binary, because the makefiles
491 generated by configure.bat necessarily use DOS line endings. Also,
492 Cygwin ports of make must run in UNIX mode, either by specifying
493 --unix on the command line, or MAKE_MODE=UNIX in the environment.
494
495 When configure runs, it attempts to detect when GCC itself, or the
496 headers it is using, are not suitable for building Emacs. GCC version
497 2.95 or later is needed, because that is when the Windows port gained
498 sufficient support for anonymous structs and unions to cope with some
499 definitions from winnt.h that are used by addsection.c.
500 Older versions of the W32 API headers that come with Cygwin and MinGW
501 may be missing some definitions required by Emacs, or broken in other
502 ways. In particular, uniscribe APIs were added to MinGW CVS only on
503 2006-03-26, so releases from before then cannot be used.
504
505 When in doubt about correctness of what configure did, look at the file
506 config.log, which shows all the failed test programs and compiler
507 messages associated with the failures. If that doesn't give a clue,
508 please report the problems, together with the relevant fragments from
509 config.log, as bugs.
510
511 If configure succeeds, but make fails, install the Cygwin port of
512 Bash, even if the table above indicates that Emacs should be able to
513 build without sh.exe. (Some versions of Windows shells are too dumb
514 for Makefile's used by Emacs.)
515
516 If you are using certain Cygwin builds of GCC, such as Cygwin version
517 1.1.8, you may need to specify some extra compiler flags like so:
518
519 configure --with-gcc --cflags -mwin32 --cflags -D__MSVCRT__
520 --ldflags -mwin32
521
522 However, the latest Cygwin versions, such as 1.3.3, don't need those
523 switches; you can simply use "configure --with-gcc".
524
525 We will attempt to auto-detect the need for these flags in a future
526 release.
527
528 * Debugging
529
530 You should be able to debug Emacs using the debugger that is
531 appropriate for the compiler you used, namely DevStudio or Windbg if
532 compiled with MSVC, or GDB if compiled with GCC. (GDB for Windows
533 is available from the MinGW site, http://www.mingw.org/download.shtml.)
534
535 When Emacs aborts due to a fatal internal error, Emacs on Windows
536 pops up an Emacs Abort Dialog asking you whether you want to debug
537 Emacs or terminate it. If Emacs was built with MSVC, click YES
538 twice, and Windbg or the DevStudio debugger will start up
539 automatically. If Emacs was built with GCC, first start GDB and
540 attach it to the Emacs process with the "gdb -p EMACS-PID" command,
541 where EMACS-PID is the Emacs process ID (which you can see in the
542 Windows Task Manager), type the "continue" command inside GDB, and
543 only then click YES on the abort dialog. This will pass control to
544 the debugger, and you will be able to debug the cause of the fatal
545 error.
546
547 Emacs functions implemented in C use a naming convention that reflects
548 their names in lisp. The names of the C routines are the lisp names
549 prefixed with 'F', and with dashes converted to underscores. For
550 example, the function call-process is implemented in C by
551 Fcall_process. Similarly, lisp variables are prefixed with 'V', again
552 with dashes converted to underscores. These conventions enable you to
553 easily set breakpoints or examine familiar lisp variables by name.
554
555 Since Emacs data is often in the form of a lisp object, and the
556 Lisp_Object type is difficult to examine manually in a debugger,
557 Emacs provides a helper routine called debug_print that prints out a
558 readable representation of a Lisp_Object. If you are using GDB,
559 there is a .gdbinit file in the src directory which provides
560 definitions that are useful for examining lisp objects. Therefore,
561 the following tips are mainly of interest when using MSVC.
562
563 The output from debug_print is sent to stderr, and to the debugger
564 via the OutputDebugString routine. The output sent to stderr should
565 be displayed in the console window that was opened when the
566 emacs.exe executable was started. The output sent to the debugger
567 should be displayed in its "Debug" output window.
568
569 When you are in the process of debugging Emacs and you would like to
570 examine the contents of a Lisp_Object variable, pop up the QuickWatch
571 window (QuickWatch has an eyeglass symbol on its button in the
572 toolbar). In the text field at the top of the window, enter
573 debug_print(<variable>) and hit return. For example, start and run
574 Emacs in the debugger until it is waiting for user input. Then click
575 on the Break button in the debugger to halt execution. Emacs should
576 halt in ZwUserGetMessage waiting for an input event. Use the Call
577 Stack window to select the procedure w32_msp_pump up the call stack
578 (see below for why you have to do this). Open the QuickWatch window
579 and enter debug_print(Vexec_path). Evaluating this expression will
580 then print out the contents of the lisp variable exec-path.
581
582 If QuickWatch reports that the symbol is unknown, then check the call
583 stack in the Call Stack window. If the selected frame in the call
584 stack is not an Emacs procedure, then the debugger won't recognize
585 Emacs symbols. Instead, select a frame that is inside an Emacs
586 procedure and try using debug_print again.
587
588 If QuickWatch invokes debug_print but nothing happens, then check the
589 thread that is selected in the debugger. If the selected thread is
590 not the last thread to run (the "current" thread), then it cannot be
591 used to execute debug_print. Use the Debug menu to select the current
592 thread and try using debug_print again. Note that the debugger halts
593 execution (e.g., due to a breakpoint) in the context of the current
594 thread, so this should only be a problem if you've explicitly switched
595 threads.
596
597 \f
598 This file is part of GNU Emacs.
599
600 GNU Emacs is free software: you can redistribute it and/or modify
601 it under the terms of the GNU General Public License as published by
602 the Free Software Foundation, either version 3 of the License, or
603 (at your option) any later version.
604
605 GNU Emacs is distributed in the hope that it will be useful,
606 but WITHOUT ANY WARRANTY; without even the implied warranty of
607 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
608 GNU General Public License for more details.
609
610 You should have received a copy of the GNU General Public License
611 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.