1 GNU M4 NEWS - User visible changes.
2 Copyright (C) 1992, 1993, 1994, 2004, 2005, 2006, 2007 Free Software
5 Version 1.4.11 - ?? ??? 2007, by ???? (git version 1.4.10a-*)
7 * Fix core dump in 'm4 -F file -t undefined', present since -F was
9 * Fix regression introduced in 1.4.9b in the `divert' builtin when more
10 than 512 kibibytes are saved in diversions on platforms like NetBSD
11 where fopen(name,"a+") seeks to the end of the file.
12 * Enhance the `defn' builtin to support concatenation of multiple text
13 arguments, as required by POSIX. However, at this time, it is not
14 possible to concatenate a builtin macro with anything else.
15 * Several improvements in `index', `regexp', and `patsubst' builtins to
16 speed up typical Autoconf usage.
17 * A number of portability improvements inherited from gnulib.
19 Version 1.4.10 - 09 Jul 2007, by Eric Blake (CVS version 1.4.9c)
21 * Upgrade from GPL version 2 to GPL version 3 or later.
22 * A number of portability improvements inherited from gnulib.
23 * Avoid undefined behavior introduced in 1.4.9b in the `format' builtin
24 when handling %c. However, this area of code has never been documented,
25 and currently does not match the POSIX behavior of printf(1), so it may
26 have further changes in the next version.
28 Version 1.4.9b - 29 May 2007, by Eric Blake (CVS version 1.4.9a)
30 * Fix regression introduced in 1.4.9 in the `eval' builtin when performing
32 * Fix regression introduced in 1.4.8 in the `-F' option that made it
33 impossible to freeze more than 512 kibibytes of diverted text.
34 * The synclines option `-s' no longer generates sync lines in the middle of
35 multiline comments or quoted strings.
36 * Work around a number of corner-case POSIX compliance bugs in various
37 broken stdio libraries. In particular, the `syscmd' builtin behaves
38 more predictably when stdin is seekable.
39 * The `format' builtin now understands formats such as %a, %A, and %'hhd,
40 and works around a number of platform printf bugs. Furthermore, the
41 sequence format(%*.*d,-1,-1,1) no longer outputs random data. However,
42 some non-compliant platforms such as mingw still have known bugs in
43 strtod that may cause testsuite failures.
44 * The testsuite is improved to also run gnulib portability tests for the
45 features that M4 imports from gnulib.
47 Version 1.4.9 - 23 Mar 2007, by Eric Blake (CVS version 1.4.8c)
49 * Minor documentation and portability cleanups.
51 Version 1.4.8b - 24 Feb 2007, by Eric Blake (CVS version 1.4.8a)
53 * Fix a regression introduced in 1.4.8 that made m4 unable to process
54 files larger than 2GiB on some platforms.
55 * Fix a regression introduced in 1.4.8 that made m4 dump core when
56 invoked as 'm4 -- file'.
57 * The `eval' builtin now follows C precedence rules. Additionally, the
58 short-circuit operators correctly short-circuit division by zero. The
59 previously undocumented alias of '=' meaning '==' in eval now triggers a
60 deprecation warning, so that a future version of M4 can implement a form
61 of variable assignment as an extension.
62 * The `include' builtin now affects exit status on failure, as required by
63 POSIX. Use `sinclude' if you need a successful exit status.
64 * The `-E'/`--fatal-warnings' command-line option now has two levels. When
65 specified only once, warnings affect exit status, but execution
66 continues, so that you can see all warnings instead of fixing them one
67 at a time. To acheive 1.4.8 behavior, where the first warning
68 immediately exits, specify -E twice on the command line.
69 * A new `--warn-macro-sequence' command-line option allows detection of
70 sequences in `define' and `pushdef' definitions that match an optional
71 regular expression. The default regular expression is
72 `\$\({[^}]*}\|[0-9][0-9]+\)', corresponding to the sequences that might
73 not behave correctly when upgrading to the eventual M4 2.0. By default,
74 M4 2.0 will follow the POSIX requirement that a macro definition
75 containing `$11' must expand to the first argument concatenated with 1,
76 rather than the eleventh argument; and will take advantage of the POSIX
77 wording that allows implementations to treat `${11}' as the eleventh
78 argument instead of literal text. Be aware that Autoconf 2.61 will not
79 work with this option enabled with the default regular expression; but
80 Autoconf 2.62 will be compatible with this option.
81 * Improved portability to platforms such as BSD/OS and AIX.
83 Version 1.4.8 - 20 November 2006, by Eric Blake (CVS version 1.4.7a)
85 * The `divert' macro and `-H'/`--hashsize' command line option no longer
86 cause a core dump when handed extra large values. Also, `divert' now
87 uses memory proportional to the number of diversions in use, rather than
88 to the maximum diversion number encountered, so that large diversion
89 numbers are less likely to exhaust system memory; and is no longer
90 limited by the maximum number of file descriptors.
91 * The `--help' and `--version' command line options now consistently
92 override all earlier options. For example, `m4 --debugfile=trace
93 --help' now no longer accidentally creates an empty file `trace'.
94 * The `-L'/`--nesting-limit' command line option can now be set to 0
95 to remove the default limit of 1024. However, it is still possible that
96 heavily nested input can cause abrupt program termination due to stack
98 * Problems encountered when writing to standard error, such as with the
99 `errprint' macro, now always cause a non-zero exit status.
100 * Warnings and errors issued during macro expansion are now consistently
101 reported at the line where the macro name was detected, rather than
102 where the close parenthesis resides. Text wrapped by `m4wrap' now
103 remembers the location that was in effect when m4wrap was invoked,
104 rather than changing to line 0 and the empty string for a file. The
105 macros `__line__' and `__file__' now work correctly even as the last
106 token in an included file.
107 * The `builtin' and `indir' macros now transparently handle builtin
108 tokens generated by `defn'.
109 * When diversions created by the `divert' macro collect enough text that
110 M4 must use temporary files, the environment variable $TMPDIR is now
111 consulted, and a better effort is made to clean up those files in the
112 event of a fatal signal.
113 * The `mkstemp' builtin is added with the same GNU semantics as `maketemp',
114 based on the recommendation of POSIX to deprecate the POSIX semantics of
115 `maketemp' as inherently insecure. In GNU mode (no -G supplied on the
116 command line), `maketemp' silently retains the secure GNU semantics, but
117 a future release of M4 will change this to emit a warning. In
118 traditional mode (m4 -G), `maketemp' now uses the POSIX-mandated insecure
119 semantics, and issues a warning that you should convert your script to
120 use `mkstemp' instead. Additionally, `mkstemp' and `maketemp' are now
121 well-defined even if the template argument does not end in six `X'
123 * The manual has been improved, including a new section on a composite
125 * The `changecom' and `changequote' macros now treat an empty second
126 argument the same as if it were missing, rather than using the empty
127 string and making it impossible to end a comment or quote.
128 * The `translit' macro now operates in linear instead of quadratic time,
129 and is now eight-bit clean.
130 * The `-D', `-U', `-s', and `-t' command line options now take effect
131 after any files encountered earlier on the command line, rather than up
132 front, as is done in traditional implementations and required by POSIX.
134 Version 1.4.7 - 25 September 2006, by Eric Blake (CVS version 1.4.6a)
136 * Fix regression from 1.4.5 in handling a file that ends in a macro
137 expansion without arguments instead of a newline.
138 * The define and pushdef macros now warn when the first argument is not
139 a string, rather than silently doing nothing.
140 * Standard input can now be read more than once, as in 'm4 - file -', and
141 is not closed until all wrapped text is handled. This makes a
142 difference when stdin is not a regular file, and also fixes bugs when
143 using the syscmd or esyscmd macros from wrapped text.
144 * When standard input is a seekable file, the m4exit, syscmd, and esyscmd
145 macros now restore the current position to the next unread byte rather
146 than discarding an arbitrary amount of buffered data.
147 * SysV command-line compatibility is no longer a goal of GNU M4; the
148 focus will be instead on POSIX compatibility. This release continues to
149 support previous usage, but adds warnings in areas which will allow a
150 future version of GNU M4 to use its own extensions without being tied to
151 the SysV command line interface.
152 * The no-op compatibility command line options -B, -N, -S, -T, and
153 --diversions may be withdrawn or assigned new meanings in future
154 releases, so they now issue a warning if used.
155 * A new command line option -i replaces the compatibility -e as the
156 short spelling of --interactive, for consistency with other GNU tools; a
157 warning is issued if the old spelling is used, and it may be assigned new
158 meaning in future releases.
159 * A new command line option --debugfile replaces the options -o and
160 --error-output as the preferred spelling. The old options were
161 misleading in their names and inconsistent with other GNU tools; they are
162 still silently accepted, but no longer documented in --help, and may be
163 assigned new meanings in future releases.
165 Version 1.4.6 - 25 August 2006, by Eric Blake (CVS version 1.4.5a)
167 * Fix buffer overruns in regexp and patsubst macros when handed a trailing
168 backslash in the replacement text, or when handling \n substitutions
169 beyond the number of \(\) groups.
170 * Fix memory leak in regexp, patsubst, and changeword macros.
171 * The format macro now understands %F, %g, and %G.
172 * When loading frozen files, m4 now exits with status 63 if version
173 mismatch is detected.
174 * Fix bugs that occurred when invoked with stdout or stderr closed,
175 and detect write failures to stdout or to the target of the
176 debugfile macro. In particular, the syscmd and esyscmd macros can
177 no longer interfere with the debug stream or diversions.
178 * The m4exit macro now converts values outside the range 0-255 to 1.
179 * It is now an error if a command-line input file ends in the middle of a
180 comment, matching the behavior of mid-string and mid-argument
182 * The dnl macro now warns if end of file is encountered instead of a
184 * The error message when end of file is encountered now uses the file and
185 line where the dangling construct started, rather than `NONE:0:'.
186 * The debugmode and __file__ macros, and the -s/--synclines option, now
187 show what directory a file was found in when the -I/--include option or
188 M4PATH variable had an effect.
189 * The changequote and changecom macros now work with 8-bit characters, and
190 quotes and comments that begin with `(' are properly recognized
192 * The new macro __program__ is added, which allows the input file to issue
193 an error message that resembles messages from m4. Warning and error
194 messages have been reformatted to comply with GNU Coding Standards.
195 * The errprint, m4wrap, and shift macros are now recognized only with
197 * The index, substr, translit, regexp, and patsubst macros now produce
198 output when given only one argument, but still warn about a missing
200 * The patsubst macro now reliably finds zero-length matches at the end
203 Version 1.4.5 - 15 July 2006, by Eric Blake (CVS version 1.4.4c)
205 * Fix sysval on BeOS, OS/2, and other systems that store exit status
206 in the low-order byte. Additionally, on Unix platforms, if syscmd was
207 terminated by a signal, sysval now displays the signal number shifted
208 left by eight bits, to match traditional m4 implementations.
209 * The maketemp macro is no longer subject to platform limitations (such as
210 26 or 32 max files from a given template).
211 * Frozen files now require that the first directive be V (version), to
212 better diagnose version mismatch. Additionally, if the F directive
213 (builtin function) names an unknown builtin that existed in the m4 that
214 froze the file but not in the current m4 (for example, changeword), the
215 warning is deferred until an attempt is made to actually use the
216 builtin. This allows downgrading from beta m4-1.4o to stable m4-1.4.5
217 without breaking autoconf.
218 * The format and indir macros are now recognized only with arguments.
219 * The eval macro no longer crashes on x86 architectures when dividing the
220 minimum integer by -1.
221 * On systems with ecvt and fcvt, format no longer truncates trailing
222 zeroes on integers printed with %.0f. On systems without these
223 functions, format is no longer subject to a buffer overflow that
224 permitted arbitrary code execution.
225 * On native Windows builds, the macro __windows__ is provided instead of
226 __unix__. Likewise, on OS/2 builds, the macro __os2__ is provided. This
227 allows input files to determine when syscmd might behave differently.
228 * Fix bug in 1.4.3 patch to use \n line-endings that did not work for
230 * When given the empty string or 0, undivert is now documented as a no-op
231 rather than closing stdout, warning about a non-existent file, or trying
232 to read a directory as a file.
233 * Many documentation improvements. Also, the manual is now distributed
234 under FDL 1.2, rather than a stricter verbatim-only license.
235 * Raise the -L (--nesting-limit) command line option limit from 250 to
237 * The decr, incr, divert, m4exit, and substr macros treat an empty number
238 as 0, issue a warning, and expand as normal; rather than issuing an error
239 and expanding to the empty string.
240 * The eval macro now treats an empty radix argument as 10, handles radix 1,
241 and treats the width argument as number of digits excluding the sign,
242 for compatibility with other m4 implementations.
243 * The ifdef, divert, m4exit, substr, and translit macros now correctly
244 ignore extra arguments.
245 * The popdef and undefine macros now correctly accept multiple arguments.
246 * Although changeword is on its last leg, if enabled, it now reverts to the
247 default (faster) regexp when passed the empty string.
248 * The regexp and substr macros now warn and ignore a trailing backslash in
249 the replacement, and warn on \n for n larger than the number of
250 sub-expressions in the regexp.
252 Version 1.4.4b - 17 June 2006, by Eric Blake (CVS version 1.4.4a)
254 * Fix a recursive push_string crashing bug, which affected changequote of
255 three or more characters on some compilers.
256 * Use automake to fix build portability issues.
257 * Fix a recursive m4wrap crashing bug.
258 * Fix a 1 in 2**32 hash crashing bug.
259 * Tracing a macro by name is now persistent, even if the macro is
260 subsequently undefined or redefined. The traceon and traceoff macros no
261 longer warn about undefined symbols. This solves a crash when using
262 indir on an undefined macro traced with the -t option, as well as an
263 incorrect result of ifdef. Furthermore, tracing is no longer transferred
264 with builtins, solving the bug of "m4 -tm4_eval" failing to give trace
265 output on the input "define(`m4_eval',defn(`eval'))m4_eval(1)".
266 * Fix a crash when a macro is undefined while collecting its arguments, by
267 always using the definition that was in effect before argument
268 collection. This behavior matches the C pre-processor, and means that
269 the sequence "define(`f',`1')f(define(`f',`2'))f" is now documented to
270 result in "12", rather than the previously undocumented "22".
271 * Update the regex engine to fix several bugs.
272 * Fix a potential crash on machines where char is signed.
274 Version 1.4.4 - October 2005, by Gary V. Vaughan
276 * ./configure --infodir=/usr/share/info now works correctly.
277 * When any file named on the command line is missing exit with status 1.
279 Version 1.4.3 - March 2005, by Gary V. Vaughan
281 * DESTDIR installs now work correctly.
282 * Don't segfault with uncompilable regexps to changeword().
283 * Always use \n line-endings for frozen files (fixes a Windows bug).
284 * Portability fix for systems lacking mkstemp(3).
285 * Approximately 20% speed up in the common case of usage with autoconf.
286 * Supported on QNX 6.3.
288 Version 1.4.2 - August 2004, by Paul Eggert
290 * No user visible changes; portability bug fixes only.
292 Version 1.4.1 - June 2004, by Paul Eggert
294 * maketemp now creates an empty file with the given name, instead of merely
295 returning the name of a nonexistent file. This closes a security hole.
297 Version 1.4 - October 1994, by Franc,ois Pinard
299 (No user visible changes)
301 Version 1.3 - September 1994, by Franc,ois Pinard
303 * Diversions are created as needed. Option `-N' is still accepted, but
304 otherwise ignored. Users should use only negative diversion numbers,
305 instead of high positive numbers, for diverting to nowhere.
307 * Diversions should also work faster. No temporary files will be needed
308 at all if all diversions taken altogether do not use more than 512K.
310 * Frozen state files may be produced with the `--freeze-state' (-F)
311 option and later brought back through the `--reload-state' (-R) option.
313 Version 1.2 - July 1994, by Franc,ois Pinard
315 * In patsubst(STRING, REGEXP, REPLACEMENT), \& in REPLACEMENT has been
316 changed to represent this part of STRING matched by the whole REGEXP,
317 instead of the whole STRING as before. \0 does the same, but emits a
318 diagnostic saying it will disappear in some subsequent release.
320 * eval(EXPR) emits a diagnostic if EXPR has suffixed crumb. The same for
321 other numeric conversions in incr(), decr(), divert(), etc.
323 * `--fatal-warnings' (-E) stops execution at first warning.
325 * `--nesting-limit=LEVEL' (-L LEVEL) sets a limit to macro nesting.
326 It is initially fixed at 250.
328 * `--word-regexp=REGEXP' (-W REGEXP) modifies macro name syntax, like
329 does the new `changeword(REGEXP)' macro. This feature is experimental,
330 tell me your opinions about it. You do need --enable-changeword at
331 configure time to get these things. Do *not* depend on them yet.
333 * Trace output format is scannable by GNU Emacs' next-error function.
335 * Stack overflow is detected and diagnosed on some capable systems.
337 * Various bugs have been corrected, m4 should be more portable. See the
338 ChangeLog for details.
340 Version 1.1 - November 1993, by Franc,ois Pinard
342 Changes which might affect existing GNU m4 scripts:
344 * Option `-V' has been removed, use `--version' instead. `--version'
345 writes on standard output instead of standard error, and inhibits any
348 * `--no-gnu-extensions' has been renamed `--traditional'.
350 * In `eval', `^' used to indicate exponentiation, use `**' instead.
352 * The automatic undiversion which takes place at end of all input is
353 forced into the main output stream.
355 Changes which are unlikely to affect existing scripts:
357 * `--help' prints an usage summary on standard output. Script execution
360 * `--prefix-builtins' (-P) prefixes all builtin macros by `m4_'.
362 * Most builtin macros for which arguments are mandatory, called without
363 any arguments, are no more recognized as builtin macros: they are
364 consequently copied verbatim to the output stream.
366 * `define' and `pushdef' are usable with only one argument, they give
367 this argument an empty definition.
369 * `eval' new operators for binary representation handling: `^' for
370 exclusive-or, `~' for the bitwise negation, `<<' and `>>' for shifts.
372 * `eval' recognizes the notation 0bDIGITS for binary numbers and the
373 notation 0rRADIX:DIGITS for numbers in any radix from 1 to 36.
375 Version 1.0.3 - December 1992, by Franc,ois Pinard
377 Changes for the user:
379 * `dnl' outputs a diagnostic if immediately followed by `('. Usually,
380 `dnl' is followed by newline or whitespace.
382 * `ifelse' accepts without complaining the common idiom of having only
383 one argument. This is useful for introducing long comments.
385 * `eval' always expresses values as signed, whatever the radix.
387 * M4OPTS environment variable is no longer obeyed.
389 * `--no-warnings' option is renamed `--silent'.
391 * Debug lines use a new format more compatible with GNU standards.
393 * Various bugs have been corrected. See the ChangeLog for details.
395 Changes for the installer:
397 * GNU m4 now uses an Autoconf-generated configure script, and should be
398 more easily portable in many ways. (Cray is not supported yet).
400 * `make check' has been made more portable, expect no errors.
402 Changes for the programmer:
404 * Sources have been fully reindented to comply with GNU standards, and
405 cleaned up in many ways.
407 * Sources have been protoized. Non-ANSI compilers are automatically
408 detected, then sources are unprotoized on the fly before compilation.
410 * GNU m4 uses newer versions of obstack, regex, getopt, etc.
412 Version 1.0 - October 1991, by Rene' Seindal
414 * Uses GNU configure, taken from the gdb distribution.
416 * Uses GNU getopt(), with long option names.
418 * The -Q/+quiet option is added, which suppresses warnings about missing
419 or superflous arguments to built-in macros.
421 * Added default options via the M4OPTS environment variable.
423 * Several minor bugs have been fixed.
425 Version 0.99 - July 1991, by Rene' Seindal
427 * The builtins `incr' and `decr' are now implemented without use of
430 * The builtin `indir' is added, to allow for indirect macro calls
431 (allows use of "illegal" macro names).
433 * The debugging and tracing facilities has been enhanced considerably.
434 See the manual for details.
436 * The -tMACRO option is added, marks MACRO for tracing as soon as it
439 * Builtins are traced after renaming iff they were before.
441 * Named files can now be undiverted.
443 * The -Nnum option can be used to increase the number of divertions
446 * Calling changecom without arguments now disables all comment handling.
448 * A bug in `dnl' is fixed.
450 * A bug in the multi-character quoting code is fixed.
452 * Several typos in the manual has been corrected. More probably persist.
454 Version 0.75 - November 1990, by Rene' Seindal
456 * Implemented search path for include files (-I option and M4PATH
457 environment variable).
459 * Implemented builtin `format' for printf-like formatting.
461 * Implemented builtin `regexp' for searching for regular expressions.
463 * Implemented builtin `patsubst' for substitution with regular
466 * Implemented builtin `esyscmd', which expands to a shell commands output.
468 * Implemented `__file__' and `__line__' for use in error messages.
470 * Implemented character ranges in `translit'.
472 * Implemented control over debugging output.
474 * Implemented multi-character quotes.
476 * Implemented multi-character comment delimiters.
478 * Changed predefined macro `gnu' to `__gnu__'.
480 * Changed predefined macro `unix' to `__unix__', when the -G option is
481 not used. With -G, `unix' is still defined.
483 * Added program name to error messages.
485 * Fixed two missing null bytes bugs.
487 Version 0.50 - January 1990, by Rene' Seindal
489 * Initial beta release.