| 1 | Building and Installing Emacs |
| 2 | on Windows NT/2K/XP and Windows 95/98/ME |
| 3 | |
| 4 | Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 |
| 5 | Free Software Foundation, Inc. |
| 6 | See the end of the file for license conditions. |
| 7 | |
| 8 | * For the impatient |
| 9 | |
| 10 | Here are the concise instructions for configuring and building the |
| 11 | native Windows binary of Emacs, for those who want to skip the |
| 12 | complex explanations and ``just do it'': |
| 13 | |
| 14 | Do not use this recipe with Cygwin. For building on Cygwin, |
| 15 | use the normal installation instructions, ../INSTALL. |
| 16 | |
| 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 |
| 32 | with the Microsoft's Visual C compiler (but see notes about using |
| 33 | VC++ 8.0 and later below): |
| 34 | |
| 35 | nmake |
| 36 | |
| 37 | For the development environments based on GNU GCC (MinGW, MSYS, |
| 38 | Cygwin - but see notes about Cygwin make below), depending on how |
| 39 | Make is called, it could be: |
| 40 | |
| 41 | make |
| 42 | or |
| 43 | mingw32-make |
| 44 | or |
| 45 | gnumake |
| 46 | or |
| 47 | gmake |
| 48 | |
| 49 | (If you are building from CVS, say "make bootstrap" or "nmake |
| 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 | |
| 55 | gmake -j 2 XMFLAGS="-j 2" |
| 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. |
| 62 | |
| 63 | 4. Generate the Info manuals (only if you are building out of CVS, and |
| 64 | if you have makeinfo.exe installed): |
| 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 | |
| 81 | If you want to build a Cygwin port of Emacs, use the instructions in |
| 82 | the INSTALL file in the main Emacs directory (the parent of this |
| 83 | directory). These instructions are for building a native Windows |
| 84 | binary of Emacs. |
| 85 | |
| 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, |
| 89 | such as converting files to DOS CR-LF format, not creating empty |
| 90 | directories, etc. We suggest to use djtarnt.exe from the GNU FTP |
| 91 | site. |
| 92 | |
| 93 | If you are building out of CVS, then some files in this directory |
| 94 | (.bat files, nmake.defs and makefile.w32-in) may need the line-ends |
| 95 | fixing first. The easiest way to do this and avoid future conflicts |
| 96 | is to run the following command in this (emacs/nt) directory: |
| 97 | |
| 98 | cvs update -kb |
| 99 | |
| 100 | Alternatively, use programs that convert end-of-line format, such as |
| 101 | dos2unix and unix2dos available from GnuWin32 or dtou and utod from |
| 102 | the DJGPP project. |
| 103 | |
| 104 | Additionally, the files lisp/international/uni-*.el and |
| 105 | lisp/ldefs-boot.el need Unix line ends due to some embedded ^M |
| 106 | characters that are not at the end of the line. So in the |
| 107 | lisp/international directory you should run the following command, or |
| 108 | use dos2unix on those files. |
| 109 | |
| 110 | cvs update -kb uni-*.el |
| 111 | |
| 112 | and in the lisp directory, use the command: |
| 113 | |
| 114 | cvs update -kb lisp/ldefs-boot.el |
| 115 | |
| 116 | In addition to this file, you should also read INSTALL.CVS in the |
| 117 | parent directory, and make sure that you have a version of |
| 118 | "touch.exe" in your path, and that it will create files that do not |
| 119 | yet exist. |
| 120 | |
| 121 | * Supported development environments |
| 122 | |
| 123 | To compile Emacs, you will need either Microsoft Visual C++ 2.0, or |
| 124 | later up to 7.0, and nmake, or a Windows port of GCC 2.95 or later |
| 125 | with MinGW and W32 API support and a port of GNU Make. You can use |
| 126 | the Cygwin ports of GCC, but Emacs requires the MinGW headers and |
| 127 | libraries to build (latest versions of the Cygwin toolkit, at least |
| 128 | since v1.3.3, include the MinGW headers and libraries as an integral |
| 129 | part). |
| 130 | |
| 131 | Note that building Emacs with Visual Studio 2005 (VC++ 8.0) is not |
| 132 | supported at this time, due to changes introduced by Microsoft into |
| 133 | the libraries shipped with the compiler. |
| 134 | |
| 135 | The rest of this file assumes you have a working development |
| 136 | environment. If you just installed such an environment, try |
| 137 | building a trivial C "Hello world" program, and see if it works. If |
| 138 | it doesn't work, resolve that problem first! If you use Microsoft |
| 139 | Visual Studio .NET 2003, don't forget to run the VCVARS32.BAT batch |
| 140 | file from the `Bin' subdirectory of the directory where you have |
| 141 | installed VS.NET. |
| 142 | |
| 143 | If you use the MinGW port of GCC and GNU Make to build Emacs, there |
| 144 | are some compatibility issues wrt Make and the shell that is run by |
| 145 | Make, either the standard COMMAND.COM/CMD.EXE supplied with Windows |
| 146 | or sh.exe., a port of a Unixy shell. For reference, below is a list |
| 147 | of which builds of GNU Make are known to work or not, and whether |
| 148 | they work in the presence and/or absence of sh.exe, the Cygwin port |
| 149 | of Bash. Note that any version of Make that is compiled with Cygwin |
| 150 | will only work with Cygwin tools, due to the use of cygwin style |
| 151 | paths. This means Cygwin Make is unsuitable for building parts of |
| 152 | Emacs that need to invoke Emacs itself (leim and "make bootstrap", |
| 153 | for example). Also see the Trouble-shooting section below if you |
| 154 | decide to go ahead and use Cygwin make. |
| 155 | |
| 156 | In addition, using 4NT as your shell is known to fail the build process, |
| 157 | at least for 4NT version 3.01. Use CMD.EXE, the default Windows shell, |
| 158 | instead. MSYS sh.exe also appears to cause various problems. If you have |
| 159 | MSYS installed, try "make SHELL=cmd.exe" to force the use of cmd.exe |
| 160 | instead of sh.exe. |
| 161 | |
| 162 | sh exists no sh |
| 163 | |
| 164 | cygwin b20.1 make (3.75): fails[1, 5] fails[2, 5] |
| 165 | MSVC compiled gmake 3.77: okay okay |
| 166 | MSVC compiled gmake 3.78.1: okay okay |
| 167 | MSVC compiled gmake 3.79.1: okay okay |
| 168 | mingw32/gcc-2.92.2 make (3.77): okay okay[4] |
| 169 | cygwin compiled gmake 3.77: fails[1, 5] fails[2, 5] |
| 170 | cygwin compiled make 3.78.1: fails[5] fails[2, 5] |
| 171 | cygwin compiled make 3.79.1: fails[3, 5] fails[2?, 5] |
| 172 | cygwin compiled make 3.80: okay[6] fails?[7] |
| 173 | cygwin compiled make 3.81: fails fails?[7] |
| 174 | mingw32 compiled make 3.79.1: okay okay |
| 175 | mingw32 compiled make 3.80: okay okay[7] |
| 176 | mingw32 compiled make 3.81: okay okay[8] |
| 177 | |
| 178 | Notes: |
| 179 | |
| 180 | [1] doesn't cope with makefiles with DOS line endings, so must mount |
| 181 | emacs source with text!=binary. |
| 182 | [2] fails when needs to invoke shell commands; okay invoking gcc etc. |
| 183 | [3] requires LC_MESSAGES support to build; cannot build with early |
| 184 | versions of cygwin. |
| 185 | [4] may fail on Windows 9X and Windows ME; if so, install Bash. |
| 186 | [5] fails when building leim due to the use of cygwin style paths. |
| 187 | May work if building emacs without leim. |
| 188 | [6] need to uncomment 3 lines in nt/gmake.defs that invoke `cygpath' |
| 189 | (look for "cygpath" near line 85 of gmake.defs). |
| 190 | [7] not recommended; please report if you try this combination. |
| 191 | [8] tested only on Windows XP. |
| 192 | |
| 193 | Other compilers may work, but specific reports from people that have |
| 194 | tried suggest that the Intel C compiler (for example) may produce an |
| 195 | Emacs executable with strange filename completion behavior. Unless |
| 196 | you would like to assist by finding and fixing the cause of any bugs |
| 197 | like this, we recommend the use of the supported compilers mentioned |
| 198 | in the previous paragraph. |
| 199 | |
| 200 | You will also need a copy of the Posix cp, rm and mv programs. These |
| 201 | and other useful Posix utilities can be obtained from one of several |
| 202 | projects: |
| 203 | |
| 204 | * http://gnuwin32.sourceforge.net/ ( GnuWin32 ) |
| 205 | * http://www.mingw.org/ ( MinGW ) |
| 206 | * http://www.cygwin.com/ ( Cygwin ) |
| 207 | * http://unxutils.sourceforge.net/ ( UnxUtils ) |
| 208 | |
| 209 | If you build Emacs on Windows 9X or ME, not on Windows 2K/XP or |
| 210 | Windows NT, we suggest to install the Cygwin port of Bash. That is |
| 211 | because the native Windows shell COMMAND.COM is too limited; the |
| 212 | Emacs build procedure tries very hard to support even such limited |
| 213 | shells, but as none of the Windows developers of Emacs work on |
| 214 | Windows 9x, we cannot guarantee that it works without a more |
| 215 | powerful shell. |
| 216 | |
| 217 | Additional instructions and help for building Emacs on Windows can be |
| 218 | found at the Emacs Wiki: |
| 219 | |
| 220 | http://www.emacswiki.org/cgi-bin/wiki/WThirtyTwoInstallationKit |
| 221 | |
| 222 | and on these URLs: |
| 223 | |
| 224 | http://ourcomments.org/Emacs/w32-build-emacs.html |
| 225 | http://derekslager.com/blog/posts/2007/01/emacs-hack-3-compile-emacs-from-cvs-on-windows.ashx |
| 226 | |
| 227 | The second URL above includes instructions for building with MSVC, |
| 228 | as well as with MinGW, while the first URL covers only MinGW, but |
| 229 | has more details about it. |
| 230 | |
| 231 | * Configuring |
| 232 | |
| 233 | Configuration of Emacs is now handled by running configure.bat in the |
| 234 | `nt' subdirectory. It will detect which compiler you have available, |
| 235 | and generate makefiles accordingly. You can override the compiler |
| 236 | detection, and control optimization and debug settings, by specifying |
| 237 | options on the command line when invoking configure. |
| 238 | |
| 239 | To configure Emacs to build with GCC or MSVC, whichever is available, |
| 240 | simply change to the `nt' subdirectory and run `configure.bat' with no |
| 241 | options. To see what options are available, run `configure --help'. |
| 242 | Do NOT use the --no-debug option to configure.bat unless you are |
| 243 | absolutely sure the produced binaries will never need to be run under |
| 244 | a debugger. |
| 245 | |
| 246 | N.B. It is normal to see a few error messages output while configure |
| 247 | is running, when gcc support is being tested. These cannot be |
| 248 | suppressed because of limitations in the Windows 9x command.com shell. |
| 249 | |
| 250 | You are encouraged to look at the file config.log which shows details |
| 251 | for failed tests, after configure.bat finishes. Any unexplained failure |
| 252 | should be investigated and perhaps reported as a bug (see the section |
| 253 | about reporting bugs in the file README in this directory and in the |
| 254 | Emacs manual). |
| 255 | |
| 256 | * Optional image library support |
| 257 | |
| 258 | In addition to its "native" image formats (pbm and xbm), Emacs can |
| 259 | handle other image types: xpm, tiff, gif, png, jpeg and experimental |
| 260 | support for svg (postscript is currently unsupported on Windows). |
| 261 | To build Emacs with support for them, the corresponding headers must |
| 262 | be in the include path when the configure script is run. This can |
| 263 | be setup using environment variables, or by specifying --cflags |
| 264 | -I... options on the command-line to configure.bat. The configure |
| 265 | script will report whether it was able to detect the headers. If |
| 266 | the results of this testing appear to be incorrect, please look for |
| 267 | details in the file config.log: it will show the failed test |
| 268 | programs and compiler error messages that should explain what is |
| 269 | wrong. (Usually, any such failures happen because some headers are |
| 270 | missing due to bad packaging of the image support libraries.) |
| 271 | |
| 272 | To use the external image support, the DLLs implementing the |
| 273 | functionality must be found when Emacs first needs them, either on the |
| 274 | PATH, or in the same directory as emacs.exe. Failure to find a |
| 275 | library is not an error; the associated image format will simply be |
| 276 | unavailable. Note that once Emacs has determined that a library can |
| 277 | not be found, there's no way to force it to try again, other than |
| 278 | restarting. See the variable `image-library-alist' to configure the |
| 279 | expected names of the libraries. |
| 280 | |
| 281 | Some image libraries have dependencies on one another, or on zlib. |
| 282 | For example, tiff support depends on the jpeg library. If you did not |
| 283 | compile the libraries yourself, you must make sure that any dependency |
| 284 | is in the PATH or otherwise accessible and that the binaries are |
| 285 | compatible (for example, that they were built with the same compiler). |
| 286 | |
| 287 | Binaries for the image libraries (among many others) can be found at |
| 288 | the GnuWin32 project. PNG, JPEG and TIFF libraries are also |
| 289 | included with GTK, which is installed along with other Free Software |
| 290 | that requires it. These are built with MinGW, but they can be used |
| 291 | with both GCC/MinGW and MSVC builds of Emacs. See the info on |
| 292 | http://ourcomments.org/Emacs/w32-build-emacs.html, under "How to Get |
| 293 | Images Support", for more details about installing image support |
| 294 | libraries. Note specifically that, due to some packaging snafus in |
| 295 | the GnuWin32-supplied image libraries, you will need to download |
| 296 | _source_ packages for some of the libraries in order to get the |
| 297 | header files necessary for building Emacs with image support. |
| 298 | |
| 299 | If GTK 2.0 is installed, addpm will arrange for its image libraries |
| 300 | to be on the DLL search path for Emacs. |
| 301 | |
| 302 | * Experimental SVG support |
| 303 | |
| 304 | SVG support is currently experimental, and not built by default. |
| 305 | Specify --with-svg and ensure you have all the dependencies in your |
| 306 | include path. Unless you have built a minimalist librsvg yourself |
| 307 | (untested), librsvg depends on a significant chunk of GTK+ to build, |
| 308 | plus a few Gnome libraries, libxml2, libbz2 and zlib at runtime. The |
| 309 | easiest way to obtain the dependencies required for building is to |
| 310 | download a pre-bundled GTK+ development environment for Windows. |
| 311 | GTK puts its header files all over the place, so you will need to |
| 312 | run pkgconfig to list the include path you will need (either passed |
| 313 | to configure.bat as --cflags options, or set in the environment). |
| 314 | |
| 315 | To use librsvg at runtime, ensure that librsvg and its dependencies |
| 316 | are on your PATH. If you didn't build librsvg yourself, you will |
| 317 | need to check with where you downloaded it from for the |
| 318 | dependencies, as there are different build options. If it is a |
| 319 | short list, then it most likely only lists the immediate |
| 320 | dependencies of librsvg, but the dependencies themselves have |
| 321 | dependencies - so don't download individual libraries from GTK+, |
| 322 | download and install the whole thing. If you think you've got all |
| 323 | the dependencies and SVG support is still not working, check your |
| 324 | PATH for other libraries that shadow the ones you downloaded. |
| 325 | Libraries of the same name from different sources may not be |
| 326 | compatible, this problem was encountered with libbzip2 from GnuWin32 |
| 327 | with libcroco from gnome.org. |
| 328 | |
| 329 | If you can see etc/images/splash.svg, then you have managed to get |
| 330 | SVG support working. Congratulations for making it through DLL hell |
| 331 | to this point. You'll probably find that some SVG images crash |
| 332 | Emacs. Problems have been observed in some images that contain |
| 333 | text, they seem to be a problem in the Windows port of Pango, or |
| 334 | maybe a problem with the way Cairo or librsvg is using it that |
| 335 | doesn't show up on other platforms. |
| 336 | |
| 337 | * Building |
| 338 | |
| 339 | After running configure, simply run the appropriate `make' program for |
| 340 | your compiler to build Emacs. For MSVC, this is nmake; for GCC, it is |
| 341 | GNU make. (If you are building out of CVS, say "make bootstrap" or |
| 342 | "nmake bootstrap" instead.) |
| 343 | |
| 344 | As the files are compiled, you will see some warning messages |
| 345 | declaring that some functions don't return a value, or that some data |
| 346 | conversions will be lossy, etc. You can safely ignore these messages. |
| 347 | The warnings may be fixed in the main FSF source at some point, but |
| 348 | until then we will just live with them. |
| 349 | |
| 350 | With GNU Make, you can use the -j command-line option to have Make |
| 351 | execute several commands at once, like this: |
| 352 | |
| 353 | gmake -j 4 XMFLAGS="-j 3" |
| 354 | |
| 355 | The XMFLAGS variable overrides the default behavior of GNU Make on |
| 356 | Windows, whereby recursive Make invocations reset the maximum number |
| 357 | of simultaneous commands to 1. The above command allows up to 4 |
| 358 | simultaneous commands at once in the top-level Make, and up to 3 in |
| 359 | each one of the recursive Make's; you can use other numbers of jobs, |
| 360 | if you wish. |
| 361 | |
| 362 | If you are building from CVS, the following commands will produce |
| 363 | the Info manuals (which are not part of the CVS repository): |
| 364 | |
| 365 | make info |
| 366 | or |
| 367 | nmake info |
| 368 | |
| 369 | Note that you will need makeinfo.exe (from the GNU Texinfo package) |
| 370 | in order for this command to succeed. |
| 371 | |
| 372 | * Installing |
| 373 | |
| 374 | To install Emacs after it has compiled, simply run `nmake install' |
| 375 | or `make install', depending on which version of the Make utility |
| 376 | do you have. |
| 377 | |
| 378 | By default, Emacs will be installed in the location where it was |
| 379 | built, but a different location can be specified either using the |
| 380 | --prefix option to configure, or by setting INSTALL_DIR when running |
| 381 | make, like so: |
| 382 | |
| 383 | make install INSTALL_DIR=D:/emacs |
| 384 | |
| 385 | (for `nmake', type "nmake install INSTALL_DIR=D:/emacs" instead). |
| 386 | |
| 387 | The install process will run addpm to setup the registry entries, and |
| 388 | to create a Start menu icon for Emacs. |
| 389 | |
| 390 | * Make targets |
| 391 | |
| 392 | The following make targets may be used by users building the source |
| 393 | distribution, or users who have checked out of CVS after |
| 394 | an initial bootstrapping. |
| 395 | |
| 396 | make |
| 397 | Builds Emacs from the available sources and pre-compiled lisp files. |
| 398 | |
| 399 | make install |
| 400 | Installs programs to the bin directory, and runs addpm to create |
| 401 | Start Menu icons. |
| 402 | |
| 403 | make clean |
| 404 | Removes object and executable files produced by the build process in |
| 405 | the current configuration. After make clean, you can rebuild with |
| 406 | the same configuration using make. |
| 407 | |
| 408 | make distclean |
| 409 | In addition to the files removed by make clean, this also removes |
| 410 | Makefiles and other generated files to get back to the state of a |
| 411 | freshly unpacked source distribution. Note that this will not remove |
| 412 | installed files, or the results of builds performed with different |
| 413 | compiler or optimization options than the current configuration. |
| 414 | After make distclean, it is necessary to run configure.bat followed |
| 415 | by make to rebuild. |
| 416 | |
| 417 | make cleanall |
| 418 | Removes object and executable files that may have been created by |
| 419 | previous builds with different configure options, in addition to |
| 420 | the files produced by the current configuration. |
| 421 | |
| 422 | make realclean |
| 423 | Removes the installed files in the bin subdirectory in addition to |
| 424 | the files removed by make cleanall. |
| 425 | |
| 426 | |
| 427 | The following targets are intended only for users who have checked out |
| 428 | of CVS. |
| 429 | |
| 430 | make bootstrap |
| 431 | Creates a temporary emacs binary with lisp source files and |
| 432 | uses it to compile the lisp files. Once the lisp files are built, |
| 433 | emacs is redumped with the compiled lisp. |
| 434 | |
| 435 | make recompile |
| 436 | Recompiles any changed lisp files after a cvs update. This saves |
| 437 | doing a full bootstrap after every update. If this or a subsequent |
| 438 | make fail, you probably need to perform a full bootstrap, though |
| 439 | running this target multiple times may eventually sort out the |
| 440 | interdependencies. |
| 441 | |
| 442 | make maintainer-clean |
| 443 | Removes everything that can be recreated, including compiled lisp |
| 444 | files, to get back to the state of a fresh CVS checkout. After make |
| 445 | maintainer-clean, it is necessary to run configure.bat and make |
| 446 | bootstrap to rebuild. Occasionally it may be necessary to run this |
| 447 | target after a cvs update. |
| 448 | |
| 449 | |
| 450 | * Trouble-shooting |
| 451 | |
| 452 | The main problems that are likely to be encountered when building |
| 453 | Emacs stem from using an old version of GCC, or old MinGW or W32 API |
| 454 | headers. Additionally, cygwin ports of GNU make may require the Emacs |
| 455 | source tree to be mounted with text!=binary, because the makefiles |
| 456 | generated by configure.bat necessarily use DOS line endings. Also, |
| 457 | cygwin ports of make must run in UNIX mode, either by specifying |
| 458 | --unix on the command line, or MAKE_MODE=UNIX in the environment. |
| 459 | |
| 460 | When configure runs, it attempts to detect when GCC itself, or the |
| 461 | headers it is using, are not suitable for building Emacs. GCC version |
| 462 | 2.95 or later is needed, because that is when the Windows port gained |
| 463 | sufficient support for anonymous structs and unions to cope with some |
| 464 | definitions from winnt.h that are used by addsection.c. |
| 465 | Older versions of the W32 API headers that come with Cygwin and MinGW |
| 466 | may be missing some definitions required by Emacs, or broken in other |
| 467 | ways. In particular, uniscribe APIs were added to MinGW CVS only on |
| 468 | 2006-03-26, so releases from before then cannot be used. |
| 469 | |
| 470 | When in doubt about correctness of what configure did, look at the file |
| 471 | config.log, which shows all the failed test programs and compiler |
| 472 | messages associated with the failures. If that doesn't give a clue, |
| 473 | please report the problems, together with the relevant fragments from |
| 474 | config.log, as bugs. |
| 475 | |
| 476 | If configure succeeds, but make fails, install the Cygwin port of |
| 477 | Bash, even if the table above indicates that Emacs should be able to |
| 478 | build without sh.exe. (Some versions of Windows shells are too dumb |
| 479 | for Makefile's used by Emacs.) |
| 480 | |
| 481 | If you are using certain Cygwin builds of GCC, such as Cygwin version |
| 482 | 1.1.8, you may need to specify some extra compiler flags like so: |
| 483 | |
| 484 | configure --with-gcc --cflags -mwin32 --cflags -D__MSVCRT__ |
| 485 | --ldflags -mwin32 |
| 486 | |
| 487 | However, the latest Cygwin versions, such as 1.3.3, don't need those |
| 488 | switches; you can simply use "configure --with-gcc". |
| 489 | |
| 490 | We will attempt to auto-detect the need for these flags in a future |
| 491 | release. |
| 492 | |
| 493 | * Debugging |
| 494 | |
| 495 | You should be able to debug Emacs using the debugger that is |
| 496 | appropriate for the compiler you used, namely DevStudio or Windbg if |
| 497 | compiled with MSVC, or GDB if compiled with GCC. (GDB for Windows |
| 498 | is available from the MinGW site, http://www.mingw.org/download.shtml.) |
| 499 | |
| 500 | When Emacs aborts due to a fatal internal error, Emacs on Windows |
| 501 | pops up an Emacs Abort Dialog asking you whether you want to debug |
| 502 | Emacs or terminate it. If Emacs was built with MSVC, click YES |
| 503 | twice, and Windbg or the DevStudio debugger will start up |
| 504 | automatically. If Emacs was built with GCC, first start GDB and |
| 505 | attach it to the Emacs process with the "gdb -p EMACS-PID" command, |
| 506 | where EMACS-PID is the Emacs process ID (which you can see in the |
| 507 | Windows Task Manager), type the "continue" command inside GDB, and |
| 508 | only then click YES on the abort dialog. This will pass control to |
| 509 | the debugger, and you will be able to debug the cause of the fatal |
| 510 | error. |
| 511 | |
| 512 | Emacs functions implemented in C use a naming convention that reflects |
| 513 | their names in lisp. The names of the C routines are the lisp names |
| 514 | prefixed with 'F', and with dashes converted to underscores. For |
| 515 | example, the function call-process is implemented in C by |
| 516 | Fcall_process. Similarly, lisp variables are prefixed with 'V', again |
| 517 | with dashes converted to underscores. These conventions enable you to |
| 518 | easily set breakpoints or examine familiar lisp variables by name. |
| 519 | |
| 520 | Since Emacs data is often in the form of a lisp object, and the |
| 521 | Lisp_Object type is difficult to examine manually in a debugger, |
| 522 | Emacs provides a helper routine called debug_print that prints out a |
| 523 | readable representation of a Lisp_Object. If you are using GDB, |
| 524 | there is a .gdbinit file in the src directory which provides |
| 525 | definitions that are useful for examining lisp objects. Therefore, |
| 526 | the following tips are mainly of interest when using MSVC. |
| 527 | |
| 528 | The output from debug_print is sent to stderr, and to the debugger |
| 529 | via the OutputDebugString routine. The output sent to stderr should |
| 530 | be displayed in the console window that was opened when the |
| 531 | emacs.exe executable was started. The output sent to the debugger |
| 532 | should be displayed in its "Debug" output window. |
| 533 | |
| 534 | When you are in the process of debugging Emacs and you would like to |
| 535 | examine the contents of a Lisp_Object variable, pop up the QuickWatch |
| 536 | window (QuickWatch has an eyeglass symbol on its button in the |
| 537 | toolbar). In the text field at the top of the window, enter |
| 538 | debug_print(<variable>) and hit return. For example, start and run |
| 539 | Emacs in the debugger until it is waiting for user input. Then click |
| 540 | on the Break button in the debugger to halt execution. Emacs should |
| 541 | halt in ZwUserGetMessage waiting for an input event. Use the Call |
| 542 | Stack window to select the procedure w32_msp_pump up the call stack |
| 543 | (see below for why you have to do this). Open the QuickWatch window |
| 544 | and enter debug_print(Vexec_path). Evaluating this expression will |
| 545 | then print out the contents of the lisp variable exec-path. |
| 546 | |
| 547 | If QuickWatch reports that the symbol is unknown, then check the call |
| 548 | stack in the Call Stack window. If the selected frame in the call |
| 549 | stack is not an Emacs procedure, then the debugger won't recognize |
| 550 | Emacs symbols. Instead, select a frame that is inside an Emacs |
| 551 | procedure and try using debug_print again. |
| 552 | |
| 553 | If QuickWatch invokes debug_print but nothing happens, then check the |
| 554 | thread that is selected in the debugger. If the selected thread is |
| 555 | not the last thread to run (the "current" thread), then it cannot be |
| 556 | used to execute debug_print. Use the Debug menu to select the current |
| 557 | thread and try using debug_print again. Note that the debugger halts |
| 558 | execution (e.g., due to a breakpoint) in the context of the current |
| 559 | thread, so this should only be a problem if you've explicitly switched |
| 560 | threads. |
| 561 | |
| 562 | \f |
| 563 | This file is part of GNU Emacs. |
| 564 | |
| 565 | GNU Emacs is free software: you can redistribute it and/or modify |
| 566 | it under the terms of the GNU General Public License as published by |
| 567 | the Free Software Foundation, either version 3 of the License, or |
| 568 | (at your option) any later version. |
| 569 | |
| 570 | GNU Emacs is distributed in the hope that it will be useful, |
| 571 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 572 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 573 | GNU General Public License for more details. |
| 574 | |
| 575 | You should have received a copy of the GNU General Public License |
| 576 | along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. |