1 GNU make NEWS -- history of user-visible changes. 9 May 1996
3 Copyright (C) 1992, 1993, 1994, 1995, 1996 Free Software Foundation, Inc.
4 See the end for copying conditions.
6 Please send GNU make bug reports to bug-gnu-utils@prep.ai.mit.edu.
10 * The directory messages printed by `-w' and implicitly in sub-makes,
11 are now omitted if Make runs no commands and has no other messages to print.
13 * Make now detects files that for whatever reason have modification times
14 in the future and gives an error. Files with such impossible timestamps
15 can result from unsynchronized clocks, or archived distributions
16 containing bogus timestamps; they confuse Make's dependency engine
19 * The new directive `sinclude' is now recognized as another name for
20 `-include', for compatibility with some other Makes.
24 * Converted to use Autoconf version 2, so `configure' has some new options.
25 See INSTALL for details.
27 * You can now send a SIGUSR1 signal to Make to toggle printing of debugging
28 output enabled by -d, at any time during the run.
32 * DJ Delorie has ported Make to MS-DOS using the GO32 extender.
33 He is maintaining the DOS port, not the GNU Make maintainer;
34 please direct bugs and questions for DOS to <djgpp@sun.soe.clarkson.edu>.
35 MS-DOS binaries are available for FTP from oak.oakland.edu:pub/msdos/djgpp.
37 * The `MAKEFLAGS' variable (in the environment or in a makefile) can now
38 contain variable definitions itself; these are treated just like
39 command-line variable definitions. Make will automatically insert any
40 variable definitions from the environment value of `MAKEFLAGS' or from
41 the command line, into the `MAKEFLAGS' value exported to children. The
42 `MAKEOVERRIDES' variable previously included in the value of `$(MAKE)'
43 for sub-makes is now included in `MAKEFLAGS' instead. As before, you can
44 reset `MAKEOVERRIDES' in your makefile to avoid putting all the variables
45 in the environment when its size is limited.
47 * If `.DELETE_ON_ERROR' appears as a target, Make will delete the target of
48 a rule if it has changed when its commands exit with a nonzero status,
49 just as when the commands get a signal.
51 * The automatic variable `$+' is new. It lists all the dependencies like
52 `$^', but preserves duplicates listed in the makefile. This is useful
53 for linking rules, where library files sometimes need to be listed twice
56 * You can now specify the `.IGNORE' and `.SILENT' special targets with
57 dependencies to limit their effects to those files. If a file appears as
58 a dependency of `.IGNORE', then errors will be ignored while running the
59 commands to update that file. Likewise if a file appears as a dependency
60 of `.SILENT', then the commands to update that file will not be printed
61 before they are run. (This change was made to conform to POSIX.2.)
65 * The automatic variables `$(@D)', `$(%D)', `$(*D)', `$(<D)', `$(?D)', and
66 `$(^D)' now omit the trailing slash from the directory name. (This change
67 was made to comply with POSIX.2.)
69 * The source distribution now includes the Info files for the Make manual.
70 There is no longer a separate distribution containing Info and DVI files.
72 * You can now set the variables `binprefix' and/or `manprefix' in
73 Makefile.in (or on the command line when installing) to install GNU make
74 under a name other than `make' (i.e., ``make binprefix=g install''
75 installs GNU make as `gmake').
77 * The built-in Texinfo rules use the new variables `TEXI2DVI_FLAGS' for
78 flags to the `texi2dvi' script, and `MAKEINFO_FLAGS' for flags to the
81 * The exit status of Make when it runs into errors is now 2 instead of 1.
82 The exit status is 1 only when using -q and some target is not up to date.
83 (This change was made to comply with POSIX.2.)
87 * It is no longer a fatal error to have a NUL character in a makefile.
88 You should never put a NUL in a makefile because it can have strange
89 results, but otherwise empty lines full of NULs (such as produced by
90 the `xmkmf' program) will always work fine.
92 * The error messages for nonexistent included makefiles now refer to the
93 makefile name and line number where the `include' appeared, so Emacs's
94 C-x ` command takes you there (in case it's a typo you need to fix).
98 * Implicit rule search for archive member references is now done in the
99 opposite order from previous versions: the whole target name `LIB(MEM)'
100 first, and just the member name and parentheses `(MEM)' second.
102 * Make now gives an error for an unterminated variable or function reference.
103 For example, `$(foo' with no matching `)' or `${bar' with no matching `}'.
105 * The new default variable `MAKE_VERSION' gives the version number of
106 Make, and a string describing the remote job support compiled in (if any).
107 Thus the value (in this release) is something like `3.69' or `3.69-Customs'.
109 * Commands in an invocation of the `shell' function are no longer run with
110 a modified environment like target commands are. As in versions before
111 3.68, they now run with the environment that `make' started with. We
112 have reversed the change made in version 3.68 because it turned out to
113 cause a paradoxical situation in cases like:
115 export variable = $(shell echo value)
117 When Make attempted to put this variable in the environment for a target
118 command, it would try expand the value by running the shell command
119 `echo value'. In version 3.68, because it constructed an environment
120 for that shell command in the same way, Make would begin to go into an
121 infinite loop and then get a fatal error when it detected the loop.
123 * The commands given for `.DEFAULT' are now used for phony targets with no
128 * You can list several archive member names inside parenthesis:
129 `lib(mem1 mem2 mem3)' is equivalent to `lib(mem1) lib(mem2) lib(mem3)'.
131 * You can use wildcards inside archive member references. For example,
132 `lib(*.o)' expands to all existing members of `lib' whose names end in
133 `.o' (e.g. `lib(a.o) lib(b.o)'); `*.a(*.o)' expands to all such members
134 of all existing files whose names end in `.a' (e.g. `foo.a(a.o)
135 foo.a(b.o) bar.a(c.o) bar.a(d.o)'.
137 * A suffix rule `.X.a' now produces two pattern rules:
138 (%.o): %.X # Previous versions produced only this.
139 %.a: %.X # Now produces this as well, just like other suffixes.
141 * The new flag `--warn-undefined-variables' says to issue a warning message
142 whenever Make expands a reference to an undefined variable.
144 * The new `-include' directive is just like `include' except that there is
145 no error (not even a warning) for a nonexistent makefile.
147 * Commands in an invocation of the `shell' function are now run with a
148 modified environment like target commands are, so you can use `export' et
149 al to set up variables for them. They used to run with the environment
150 that `make' started with.
154 * `make --version' (or `make -v') now exits immediately after printing
159 * Make now supports long-named members in `ar' archive files.
163 * Make now supports the `+=' syntax for a variable definition which appends
164 to the variable's previous value. See the section `Appending More Text
165 to Variables' in the manual for full details.
167 * The new option `--no-print-directory' inhibits the `-w' or
168 `--print-directory' feature. Make turns on `--print-directory'
169 automatically if you use `-C' or `--directory', and in sub-makes; some
170 users have found this behavior undesirable.
172 * The built-in implicit rules now support the alternative extension
173 `.txinfo' for Texinfo files, just like `.texinfo' and `.texi'.
177 * Make now uses a standard GNU `configure' script. See the new file
178 INSTALL for the new (and much simpler) installation procedure.
180 * There is now a shell script to build Make the first time, if you have no
181 other `make' program. `build.sh' is created by `configure'; see README.
183 * GNU Make now completely conforms to the POSIX.2 specification for `make'.
185 * Elements of the `$^' and `$?' automatic variables that are archive
186 member references now list only the member name, as in Unix and POSIX.2.
188 * You should no longer ever need to specify the `-w' switch, which prints
189 the current directory before and after Make runs. The `-C' switch to
190 change directory, and recursive use of Make, now set `-w' automatically.
192 * Multiple double-colon rules for the same target will no longer have their
193 commands run simultaneously under -j, as this could result in the two
194 commands trying to change the file at the same time and interfering with
197 * The `SHELL' variable is now never taken from the environment.
198 Each makefile that wants a shell other than the default (/bin/sh) must
199 set SHELL itself. SHELL is always exported to child processes.
200 This change was made for compatibility with POSIX.2.
202 * Make now accepts long options. There is now an informative usage message
203 that tells you what all the options are and what they do. Try `make --help'.
205 * There are two new directives: `export' and `unexport'. All variables are
206 no longer automatically put into the environments of the commands that
207 Make runs. Instead, only variables specified on the command line or in
208 the environment are exported by default. To export others, use:
210 or you can define variables with:
211 export VARIABLE = VALUE
213 export VARIABLE := VALUE
217 .EXPORT_ALL_VARIABLES:
218 to get the old behavior. See the node `Variables/Recursion' in the manual
219 for a full description.
221 * The commands from the `.DEFAULT' special target are only applied to
222 targets which have no rules at all, not all targets with no commands.
223 This change was made for compatibility with Unix make.
225 * All fatal error messages now contain `***', so they are easy to find in
228 * Dependency file names like `-lNAME' are now replaced with the actual file
229 name found, as with files found by normal directory search (VPATH).
230 The library file `libNAME.a' may now be found in the current directory,
231 which is checked before VPATH; the standard set of directories (/lib,
232 /usr/lib, /usr/local/lib) is now checked last.
233 See the node `Libraries/Search' in the manual for full details.
235 * A single `include' directive can now specify more than one makefile to
238 You can also use shell file name patterns in an `include' directive:
241 * The default directories to search for included makefiles, and for
242 libraries specified with `-lNAME', are now set by configuration.
244 * You can now use blanks as well as colons to separate the directories in a
245 search path for the `vpath' directive or the `VPATH' variable.
247 * You can now use variables and functions in the left hand side of a
248 variable assignment, as in "$(foo)bar = value".
250 * The `MAKE' variable is always defined as `$(MAKE_COMMAND) $(MAKEOVERRIDES)'.
251 The `MAKE_COMMAND' variable is now defined to the name with which make
254 * The built-in rules for C++ compilation now use the variables `$(CXX)' and
255 `$(CXXFLAGS)' instead of `$(C++)' and `$(C++FLAGS)'. The old names had
256 problems with shells that cannot have `+' in environment variable names.
258 * The value of a recursively expanded variable is now expanded when putting
259 it into the environment for child processes. This change was made for
260 compatibility with Unix make.
262 * A rule with no targets before the `:' is now accepted and ignored.
263 This change was made for compatibility with SunOS 4 make.
264 We do not recommend that you write your makefiles to take advantage of this.
266 * The `-I' switch can now be used in MAKEFLAGS, and are put there
267 automatically just like other switches.
271 * Built-in rules for C++ source files with the `.C' suffix.
272 We still recommend that you use `.cc' instead.
274 * If commands are given too many times for a single target,
275 the last set given is used, and a warning message is printed.
277 * Error messages about makefiles are in standard GNU error format,
278 so C-x ` in Emacs works on them.
280 * Dependencies of pattern rules which contain no % need not actually exist
281 if they can be created (just like dependencies which do have a %).
285 * A message is always printed when Make decides there is nothing to be done.
286 It used to be that no message was printed for top-level phony targets
287 (because "`phony' is up to date" isn't quite right). Now a different
288 message "Nothing to be done for `phony'" is printed in that case.
290 * Archives on AIX now supposedly work.
292 * When the commands specified for .DEFAULT are used to update a target,
293 the $< automatic variable is given the same value as $@ for that target.
294 This is how Unix make behaves, and this behavior is mandated by POSIX.2.
298 * The -n, -q, and -t options are not put in the `MAKEFLAGS' and `MFLAG'
299 variables while remaking makefiles, so recursive makes done while remaking
300 makefiles will behave properly.
302 * If the special target `.NOEXPORT' is specified in a makefile,
303 only variables that came from the environment and variables
304 defined on the command line are exported.
308 * Suffix rules may have dependencies (which are ignored).
312 * Dependencies of the form `-lLIB' are searched for as /usr/local/lib/libLIB.a
313 as well as libLIB.a in /usr/lib, /lib, the current directory, and VPATH.
317 * There is now a Unix man page for GNU Make. It is certainly not a replacement
318 for the Texinfo manual, but it documents the basic functionality and the
319 switches. For full documentation, you should still read the Texinfo manual.
320 Thanks to Dennis Morse of Stanford University for contributing the initial
323 * Variables which are defined by default (e.g., `CC') will no longer be put
324 into the environment for child processes. (If these variables are reset by the
325 environment, makefiles, or the command line, they will still go into the
328 * Makefiles which have commands but no dependencies (and thus are always
329 considered out of date and in need of remaking), will not be remade (if they
330 were being remade only because they were makefiles). This means that GNU
331 Make will no longer go into an infinite loop when fed the makefiles that
332 `imake' (necessary to build X Windows) produces.
334 * There is no longer a warning for using the `vpath' directive with an explicit
335 pathname (instead of a `%' pattern).
339 * When removing intermediate files, only one `rm' command line is printed,
340 listing all file names.
342 * There are now automatic variables `$(^D)', `$(^F)', `$(?D)', and `$(?F)'.
343 These are the directory-only and file-only versions of `$^' and `$?'.
345 * Library dependencies given as `-lNAME' will use "libNAME.a" in the current
346 directory if it exists.
348 * The automatic variable `$($/)' is no longer defined.
350 * Leading `+' characters on a command line make that line be executed even
351 under -n, -t, or -q (as if the line contained `$(MAKE)').
353 * For command lines containing `$(MAKE)', `${MAKE}', or leading `+' characters,
354 only those lines are executed, not their entire rules.
355 (This is how Unix make behaves for lines containing `$(MAKE)' or `${MAKE}'.)
359 * Filenames in rules will now have ~ and ~USER expanded.
361 * The `-p' output has been changed so it can be used as a makefile.
362 (All information that isn't specified by makefiles is prefaced with comment
367 * The % character can be quoted with backslash in implicit pattern rules,
368 static pattern rules, `vpath' directives, and `patsubst', `filter', and
369 `filter-out' functions. A warning is issued if a `vpath' directive's
370 pattern contains no %.
372 * The `wildcard' variable expansion function now expands ~ and ~USER.
374 * Messages indicating failed commands now contain the target name:
375 make: *** [target] Error 1
377 * The `-p' output format has been changed somewhat to look more like
378 makefile rules and to give all information that Make has about files.
384 * The `-l' switch with no argument removes any previous load-average limit.
386 * When the `-w' switch is in effect, and Make has updated makefiles,
387 it will write a `Leaving directory' messagfe before re-executing itself.
388 This makes the `directory change tracking' changes to Emacs's compilation
389 commands work properly.
393 * The automatic variable `$*' is now defined for explicit rules,
394 as it is in Unix make.
398 * The `-j' switch is now put in the MAKEFLAGS and MFLAGS variables when
399 specified without an argument (indicating infinite jobs).
400 The `-l' switch is not always put in the MAKEFLAGS and MFLAGS variables.
402 * Make no longer checks hashed directories after running commands.
403 The behavior implemented in 3.41 caused too much slowdown.
407 * A dependency is NOT considered newer than its dependent if
408 they have the same modification time. The behavior implemented
409 in 3.43 conflicts with RCS.
413 * Dependency loops are no longer fatal errors.
415 * A dependency is considered newer than its dependent if
416 they have the same modification time.
420 * The variables F77 and F77FLAGS are now set by default to $(FC) and
421 $(FFLAGS). Makefiles designed for System V make may use these variables in
422 explicit rules and expect them to be set. Unfortunately, there is no way to
423 make setting these affect the Fortran implicit rules unless FC and FFLAGS
424 are not used (and these are used by BSD make).
428 * Make now checks to see if its hashed directories are changed by commands.
429 Other makes that hash directories (Sun, 4.3 BSD) don't do this.
433 * The `shell' function no longer captures standard error output.
437 * A file beginning with a dot can be the default target if it also contains
438 a slash (e.g., `../bin/foo'). (Unix make allows this as well.)
442 * Archive member names are truncated to 15 characters.
444 * Yet more USG stuff.
446 * Minimal support for Microport System V (a 16-bit machine and a
447 brain-damaged compiler). This has even lower priority than other USG
448 support, so if it gets beyond trivial, I will take it out completely.
450 * Revamped default implicit rules (not much visible change).
452 * The -d and -p options can come from the environment.
456 * Improved support for USG and HPUX (hopefully).
458 * A variable reference like `$(foo:a=b)', if `a' contains a `%', is
459 equivalent to `$(patsubst a,b,$(foo))'.
461 * Defining .DEFAULT with no deps or commands clears its commands.
463 * New default implicit rules for .S (cpp, then as), and .sh (copy and make
464 executable). All default implicit rules that use cpp (even indirectly), use
469 * Giving the -j option with no arguments gives you infinite jobs.
473 * New option: "-l LOAD" says not to start any new jobs while others are
474 running if the load average is not below LOAD (a floating-point number).
476 * There is support in place for implementations of remote command execution
477 in Make. See the file remote.c.
481 * No more than 10 directories will be kept open at once.
482 (This number can be changed by redefining MAX_OPEN_DIRECTORIES in dir.c.)
486 * Archive files will have their modification times recorded before doing
487 anything that might change their modification times by updating an archive
492 * The `MAKELEVEL' variable is defined for use by makefiles.
496 * The recursion level indications in error messages are much shorter than
497 they were in version 3.14.
501 * Leading spaces before directives are ignored (as documented).
503 * Included makefiles can determine the default goal target.
504 (System V Make does it this way, so we are being compatible).
508 * Variables that are defaults built into Make will not be put in the
509 environment for children. This just saves some environment space and,
510 except under -e, will be transparent to sub-makes.
512 * Error messages from sub-makes will indicate the level of recursion.
514 * Hopefully some speed-up for large directories due to a change in the
515 directory hashing scheme.
517 * One child will always get a standard input that is usable.
519 * Default makefiles that don't exist will be remade and read in.
523 * Count parentheses inside expansion function calls so you can
524 have nested calls: `$(sort $(foreach x,a b,$(x)))'.
528 * Several bug fixes, including USG and Sun386i support.
530 * `shell' function to expand shell commands a la `
532 * If the `-d' flag is given, version information will be printed.
534 * The `-c' option has been renamed to `-C' for compatibility with tar.
536 * The `-p' option no longer inhibits other normal operation.
538 * Makefiles will be updated and re-read if necessary.
540 * Can now run several commands at once (parallelism), -j option.
542 * Error messages will contain the level of Make recursion, if any.
544 * The `MAKEFLAGS' and `MFLAGS' variables will be scanned for options after
547 * A double-colon rule with no dependencies will always have its commands run.
548 (This is how both the BSD and System V versions of Make do it.)
552 (Changes from versions 1 through 3.05 were never recorded. Sorry.)
554 ----------------------------------------------------------------------
555 Copyright information:
557 Copyright (C) 1992, 1993, 1994, 1995, 1996 Free Software Foundation, Inc.
559 Permission is granted to anyone to make or distribute verbatim copies
560 of this document as received, in any medium, provided that the
561 copyright notice and this permission notice are preserved,
562 thus giving the recipient permission to redistribute in turn.
564 Permission is granted to distribute modified versions
565 of this document, or of portions of it,
566 under the above conditions, provided also that they
567 carry prominent notices stating who last changed them.
570 version-control: never