1 GNU M4 NEWS - User visible changes.
2 Copyright (C) 1992, 1993, 1994, 2004, 2005, 2006 Free Software
5 Version 1.4.8 - ?? ??? 2006, by ?? (CVS version 1.4.7a)
7 * The `divert' macro and `-H'/`--hashsize' command line option no longer
8 cause a core dump when handed extra large values.
9 * The `--help' and `--version' command line options now consistently
10 override all earlier options. For example, `m4 --debugfile=trace
11 --help' now no longer accidentally creates an empty file `trace'.
12 * The `-L'/`--nesting-limit' command line option can now be set to 0
13 to remove the default limit of 1024. However, it is still possible that
14 heavily nested input can cause abrupt program termination due to stack
16 * Problems encountered when writing to standard error, such as with the
17 `errprint' macro, now always cause a non-zero exit status.
18 * Warnings and errors issued during macro expansion are now consistently
19 reported at the line where the macro name was detected, rather than
20 where the close parenthesis resides. Text wrapped by `m4wrap' now
21 remembers the location that was in effect when m4wrap was invoked,
22 rather than changing to line 0 and the empty string for a file. The
23 macros `__line__' and `__file__' now work correctly even as the last
24 token in an included file.
25 * The `builtin' and `indir' macros now transparently handle builtin
26 tokens generated by `defn'.
27 * When diversions created by the `divert' macro collect enough text that
28 M4 must use temporary files, the environment variable $TMPDIR is now
29 consulted, and a better effort is made to clean up those files in the
30 event of a fatal signal.
31 * The `mkstemp' builtin is added with the same GNU semantics as `maketemp',
32 based on the recommendation of POSIX to deprecate the POSIX semantics of
33 `maketemp' as inherently insecure. In GNU mode (no -G supplied on the
34 command line), `maketemp' silently retains the secure GNU semantics, but
35 a future release of M4 will change this to emit a warning. In
36 traditional mode (m4 -G), `maketemp' now uses the POSIX-mandated insecure
37 semantics, and issues a warning that you should convert your script to
38 use `mkstemp' instead. Additionally, `mkstemp' and `maketemp' are now
39 well-defined even if the template argument does not end in six `X'
41 * The manual has been improved, including a new section on a composite
44 Version 1.4.7 - 25 September 2006, by Eric Blake (CVS version 1.4.6a)
46 * Fix regression from 1.4.5 in handling a file that ends in a macro
47 expansion without arguments instead of a newline.
48 * The define and pushdef macros now warn when the first argument is not
49 a string, rather than silently doing nothing.
50 * Standard input can now be read more than once, as in 'm4 - file -', and
51 is not closed until all wrapped text is handled. This makes a
52 difference when stdin is not a regular file, and also fixes bugs when
53 using the syscmd or esyscmd macros from wrapped text.
54 * When standard input is a seekable file, the m4exit, syscmd, and esyscmd
55 macros now restore the current position to the next unread byte rather
56 than discarding an arbitrary amount of buffered data.
57 * SysV command-line compatibility is no longer a goal of GNU M4; the
58 focus will be instead on POSIX compatibility. This release continues to
59 support previous usage, but adds warnings in areas which will allow a
60 future version of GNU M4 to use its own extensions without being tied to
61 the SysV command line interface.
62 * The no-op compatibility command line options -B, -N, -S, -T, and
63 --diversions may be withdrawn or assigned new meanings in future
64 releases, so they now issue a warning if used.
65 * A new command line option -i replaces the compatibility -e as the
66 short spelling of --interactive, for consistency with other GNU tools; a
67 warning is issued if the old spelling is used, and it may be assigned new
68 meaning in future releases.
69 * A new command line option --debugfile replaces the options -o and
70 --error-output as the preferred spelling. The old options were
71 misleading in their names and inconsistent with other GNU tools; they are
72 still silently accepted, but no longer documented in --help, and may be
73 assigned new meanings in future releases.
75 Version 1.4.6 - 25 August 2006, by Eric Blake (CVS version 1.4.5a)
77 * Fix buffer overruns in regexp and patsubst macros when handed a trailing
78 backslash in the replacement text, or when handling \n substitutions
79 beyond the number of \(\) groups.
80 * Fix memory leak in regexp, patsubst, and changeword macros.
81 * The format macro now understands %F, %g, and %G.
82 * When loading frozen files, m4 now exits with status 63 if version
84 * Fix bugs that occurred when invoked with stdout or stderr closed,
85 and detect write failures to stdout or to the target of the
86 debugfile macro. In particular, the syscmd and esyscmd macros can
87 no longer interfere with the debug stream or diversions.
88 * The m4exit macro now converts values outside the range 0-255 to 1.
89 * It is now an error if a command-line input file ends in the middle of a
90 comment, matching the behavior of mid-string and mid-argument
92 * The dnl macro now warns if end of file is encountered instead of a
94 * The error message when end of file is encountered now uses the file and
95 line where the dangling construct started, rather than `NONE:0:'.
96 * The debugmode and __file__ macros, and the -s/--synclines option, now
97 show what directory a file was found in when the -I/--include option or
98 M4PATH variable had an effect.
99 * The changequote and changecom macros now work with 8-bit characters, and
100 quotes and comments that begin with `(' are properly recognized
102 * The new macro __program__ is added, which allows the input file to issue
103 an error message that resembles messages from m4. Warning and error
104 messages have been reformatted to comply with GNU Coding Standards.
105 * The errprint, m4wrap, and shift macros are now recognized only with
107 * The index, substr, translit, regexp, and patsubst macros now produce
108 output when given only one argument, but still warn about a missing
110 * The patsubst macro now reliably finds zero-length matches at the end
113 Version 1.4.5 - 15 July 2006, by Eric Blake (CVS version 1.4.4c)
115 * Fix sysval on BeOS, OS/2, and other systems that store exit status
116 in the low-order byte. Additionally, on Unix platforms, if syscmd was
117 terminated by a signal, sysval now displays the signal number shifted
118 left by eight bits, to match traditional m4 implementations.
119 * The maketemp macro is no longer subject to platform limitations (such as
120 26 or 32 max files from a given template).
121 * Frozen files now require that the first directive be V (version), to
122 better diagnose version mismatch. Additionally, if the F directive
123 (builtin function) names an unknown builtin that existed in the m4 that
124 froze the file but not in the current m4 (for example, changeword), the
125 warning is deferred until an attempt is made to actually use the
126 builtin. This allows downgrading from beta m4-1.4o to stable m4-1.4.5
127 without breaking autoconf.
128 * The format and indir macros are now recognized only with arguments.
129 * The eval macro no longer crashes on x86 architectures when dividing the
130 minimum integer by -1.
131 * On systems with ecvt and fcvt, format no longer truncates trailing
132 zeroes on integers printed with %.0f. On systems without these
133 functions, format is no longer subject to a buffer overflow that
134 permitted arbitrary code execution.
135 * On native Windows builds, the macro __windows__ is provided instead of
136 __unix__. Likewise, on OS/2 builds, the macro __os2__ is provided. This
137 allows input files to determine when syscmd might behave differently.
138 * Fix bug in 1.4.3 patch to use \n line-endings that did not work for
140 * When given the empty string or 0, undivert is now documented as a no-op
141 rather than closing stdout, warning about a non-existent file, or trying
142 to read a directory as a file.
143 * Many documentation improvements. Also, the manual is now distributed
144 under FDL 1.2, rather than a stricter verbatim-only license.
145 * Raise the -L (--nesting-limit) command line option limit from 250 to
147 * The decr, incr, divert, m4exit, and substr macros treat an empty number
148 as 0, issue a warning, and expand as normal; rather than issuing an error
149 and expanding to the empty string.
150 * The eval macro now treats an empty radix argument as 10, handles radix 1,
151 and treats the width argument as number of digits excluding the sign,
152 for compatibility with other m4 implementations.
153 * The ifdef, divert, m4exit, substr, and translit macros now correctly
154 ignore extra arguments.
155 * The popdef and undefine macros now correctly accept multiple arguments.
156 * Although changeword is on its last leg, if enabled, it now reverts to the
157 default (faster) regexp when passed the empty string.
158 * The regexp and substr macros now warn and ignore a trailing backslash in
159 the replacement, and warn on \n for n larger than the number of
160 sub-expressions in the regexp.
162 Version 1.4.4b - 17 June 2006, by Eric Blake (CVS version 1.4.4a)
164 * Fix a recursive push_string crashing bug, which affected changequote of
165 three or more characters on some compilers.
166 * Use automake to fix build portability issues.
167 * Fix a recursive m4wrap crashing bug.
168 * Fix a 1 in 2**32 hash crashing bug.
169 * Tracing a macro by name is now persistent, even if the macro is
170 subsequently undefined or redefined. The traceon and traceoff macros no
171 longer warn about undefined symbols. This solves a crash when using
172 indir on an undefined macro traced with the -t option, as well as an
173 incorrect result of ifdef. Furthermore, tracing is no longer transferred
174 with builtins, solving the bug of "m4 -tm4_eval" failing to give trace
175 output on the input "define(`m4_eval',defn(`eval'))m4_eval(1)".
176 * Fix a crash when a macro is undefined while collecting its arguments, by
177 always using the definition that was in effect before argument
178 collection. This behavior matches the C pre-processor, and means that
179 the sequence "define(`f',`1')f(define(`f',`2'))f" is now documented to
180 result in "12", rather than the previously undocumented "22".
181 * Update the regex engine to fix several bugs.
182 * Fix a potential crash on machines where char is signed.
184 Version 1.4.4 - October 2005, by Gary V. Vaughan
186 * ./configure --infodir=/usr/share/info now works correctly.
187 * When any file named on the command line is missing exit with status 1.
189 Version 1.4.3 - March 2005, by Gary V. Vaughan
191 * DESTDIR installs now work correctly.
192 * Don't segfault with uncompilable regexps to changeword().
193 * Always use \n line-endings for frozen files (fixes a Windows bug).
194 * Portability fix for systems lacking mkstemp(3).
195 * Approximately 20% speed up in the common case of usage with autoconf.
196 * Supported on QNX 6.3.
198 Version 1.4.2 - August 2004, by Paul Eggert
200 * No user visible changes; portability bug fixes only.
202 Version 1.4.1 - June 2004, by Paul Eggert
204 * maketemp now creates an empty file with the given name, instead of merely
205 returning the name of a nonexistent file. This closes a security hole.
207 Version 1.4 - October 1994, by Franc,ois Pinard
209 (No user visible changes)
211 Version 1.3 - September 1994, by Franc,ois Pinard
213 * Diversions are created as needed. Option `-N' is still accepted, but
214 otherwise ignored. Users should use only negative diversion numbers,
215 instead of high positive numbers, for diverting to nowhere.
217 * Diversions should also work faster. No temporary files will be needed
218 at all if all diversions taken altogether do not use more than 512K.
220 * Frozen state files may be produced with the `--freeze-state' (-F)
221 option and later brought back through the `--reload-state' (-R) option.
223 Version 1.2 - July 1994, by Franc,ois Pinard
225 * In patsubst(STRING, REGEXP, REPLACEMENT), \& in REPLACEMENT has been
226 changed to represent this part of STRING matched by the whole REGEXP,
227 instead of the whole STRING as before. \0 does the same, but emits a
228 diagnostic saying it will disappear in some subsequent release.
230 * eval(EXPR) emits a diagnostic if EXPR has suffixed crumb. The same for
231 other numeric conversions in incr(), decr(), divert(), etc.
233 * `--fatal-warnings' (-E) stops execution at first warning.
235 * `--nesting-limit=LEVEL' (-L LEVEL) sets a limit to macro nesting.
236 It is initially fixed at 250.
238 * `--word-regexp=REGEXP' (-W REGEXP) modifies macro name syntax, like
239 does the new `changeword(REGEXP)' macro. This feature is experimental,
240 tell me your opinions about it. You do need --enable-changeword at
241 configure time to get these things. Do *not* depend on them yet.
243 * Trace output format is scannable by GNU Emacs' next-error function.
245 * Stack overflow is detected and diagnosed on some capable systems.
247 * Various bugs have been corrected, m4 should be more portable. See the
248 ChangeLog for details.
250 Version 1.1 - November 1993, by Franc,ois Pinard
252 Changes which might affect existing GNU m4 scripts:
254 * Option `-V' has been removed, use `--version' instead. `--version'
255 writes on standard output instead of standard error, and inhibits any
258 * `--no-gnu-extensions' has been renamed `--traditional'.
260 * In `eval', `^' used to indicate exponentiation, use `**' instead.
262 * The automatic undiversion which takes place at end of all input is
263 forced into the main output stream.
265 Changes which are unlikely to affect existing scripts:
267 * `--help' prints an usage summary on standard output. Script execution
270 * `--prefix-builtins' (-P) prefixes all builtin macros by `m4_'.
272 * Most builtin macros for which arguments are mandatory, called without
273 any arguments, are no more recognized as builtin macros: they are
274 consequently copied verbatim to the output stream.
276 * `define' and `pushdef' are usable with only one argument, they give
277 this argument an empty definition.
279 * `eval' new operators for binary representation handling: `^' for
280 exclusive-or, `~' for the bitwise negation, `<<' and `>>' for shifts.
282 * `eval' recognizes the notation 0bDIGITS for binary numbers and the
283 notation 0rRADIX:DIGITS for numbers in any radix from 1 to 36.
285 Version 1.0.3 - December 1992, by Franc,ois Pinard
287 Changes for the user:
289 * `dnl' outputs a diagnostic if immediately followed by `('. Usually,
290 `dnl' is followed by newline or whitespace.
292 * `ifelse' accepts without complaining the common idiom of having only
293 one argument. This is useful for introducing long comments.
295 * `eval' always expresses values as signed, whatever the radix.
297 * M4OPTS environment variable is no longer obeyed.
299 * `--no-warnings' option is renamed `--silent'.
301 * Debug lines use a new format more compatible with GNU standards.
303 * Various bugs have been corrected. See the ChangeLog for details.
305 Changes for the installer:
307 * GNU m4 now uses an Autoconf-generated configure script, and should be
308 more easily portable in many ways. (Cray is not supported yet).
310 * `make check' has been made more portable, expect no errors.
312 Changes for the programmer:
314 * Sources have been fully reindented to comply with GNU standards, and
315 cleaned up in many ways.
317 * Sources have been protoized. Non-ANSI compilers are automatically
318 detected, then sources are unprotoized on the fly before compilation.
320 * GNU m4 uses newer versions of obstack, regex, getopt, etc.
322 Version 1.0 - October 1991, by Rene' Seindal
324 * Uses GNU configure, taken from the gdb distribution.
326 * Uses GNU getopt(), with long option names.
328 * The -Q/+quiet option is added, which suppresses warnings about missing
329 or superflous arguments to built-in macros.
331 * Added default options via the M4OPTS environment variable.
333 * Several minor bugs have been fixed.
335 Version 0.99 - July 1991, by Rene' Seindal
337 * The builtins `incr' and `decr' are now implemented without use of
340 * The builtin `indir' is added, to allow for indirect macro calls
341 (allows use of "illegal" macro names).
343 * The debugging and tracing facilities has been enhanced considerably.
344 See the manual for details.
346 * The -tMACRO option is added, marks MACRO for tracing as soon as it
349 * Builtins are traced after renaming iff they were before.
351 * Named files can now be undiverted.
353 * The -Nnum option can be used to increase the number of divertions
356 * Calling changecom without arguments now disables all comment handling.
358 * A bug in `dnl' is fixed.
360 * A bug in the multi-character quoting code is fixed.
362 * Several typos in the manual has been corrected. More probably persist.
364 Version 0.75 - November 1990, by Rene' Seindal
366 * Implemented search path for include files (-I option and M4PATH
367 environment variable).
369 * Implemented builtin `format' for printf-like formatting.
371 * Implemented builtin `regexp' for searching for regular expressions.
373 * Implemented builtin `patsubst' for substitution with regular
376 * Implemented builtin `esyscmd', which expands to a shell commands output.
378 * Implemented `__file__' and `__line__' for use in error messages.
380 * Implemented character ranges in `translit'.
382 * Implemented control over debugging output.
384 * Implemented multi-character quotes.
386 * Implemented multi-character comment delimiters.
388 * Changed predefined macro `gnu' to `__gnu__'.
390 * Changed predefined macro `unix' to `__unix__', when the -G option is
391 not used. With -G, `unix' is still defined.
393 * Added program name to error messages.
395 * Fixed two missing null bytes bugs.
397 Version 0.50 - January 1990, by Rene' Seindal
399 * Initial beta release.