1 GNU make NEWS -- history of user-visible changes. 28 February 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
21 * Converted to use Autoconf version 2, so `configure' has some new options.
22 See INSTALL for details.
24 * You can now send a SIGUSR1 signal to Make to toggle printing of debugging
25 output enabled by -d, at any time during the run.
29 * DJ Delorie has ported Make to MS-DOS using the GO32 extender.
30 He is maintaining the DOS port, not the GNU Make maintainer;
31 please direct bugs and questions for DOS to <djgpp@sun.soe.clarkson.edu>.
32 MS-DOS binaries are available for FTP from oak.oakland.edu:pub/msdos/djgpp.
34 * The `MAKEFLAGS' variable (in the environment or in a makefile) can now
35 contain variable definitions itself; these are treated just like
36 command-line variable definitions. Make will automatically insert any
37 variable definitions from the environment value of `MAKEFLAGS' or from
38 the command line, into the `MAKEFLAGS' value exported to children. The
39 `MAKEOVERRIDES' variable previously included in the value of `$(MAKE)'
40 for sub-makes is now included in `MAKEFLAGS' instead. As before, you can
41 reset `MAKEOVERRIDES' in your makefile to avoid putting all the variables
42 in the environment when its size is limited.
44 * If `.DELETE_ON_ERROR' appears as a target, Make will delete the target of
45 a rule if it has changed when its commands exit with a nonzero status,
46 just as when the commands get a signal.
48 * The automatic variable `$+' is new. It lists all the dependencies like
49 `$^', but preserves duplicates listed in the makefile. This is useful
50 for linking rules, where library files sometimes need to be listed twice
53 * You can now specify the `.IGNORE' and `.SILENT' special targets with
54 dependencies to limit their effects to those files. If a file appears as
55 a dependency of `.IGNORE', then errors will be ignored while running the
56 commands to update that file. Likewise if a file appears as a dependency
57 of `.SILENT', then the commands to update that file will not be printed
58 before they are run. (This change was made to conform to POSIX.2.)
62 * The automatic variables `$(@D)', `$(%D)', `$(*D)', `$(<D)', `$(?D)', and
63 `$(^D)' now omit the trailing slash from the directory name. (This change
64 was made to comply with POSIX.2.)
66 * The source distribution now includes the Info files for the Make manual.
67 There is no longer a separate distribution containing Info and DVI files.
69 * You can now set the variables `binprefix' and/or `manprefix' in
70 Makefile.in (or on the command line when installing) to install GNU make
71 under a name other than `make' (i.e., ``make binprefix=g install''
72 installs GNU make as `gmake').
74 * The built-in Texinfo rules use the new variables `TEXI2DVI_FLAGS' for
75 flags to the `texi2dvi' script, and `MAKEINFO_FLAGS' for flags to the
78 * The exit status of Make when it runs into errors is now 2 instead of 1.
79 The exit status is 1 only when using -q and some target is not up to date.
80 (This change was made to comply with POSIX.2.)
84 * It is no longer a fatal error to have a NUL character in a makefile.
85 You should never put a NUL in a makefile because it can have strange
86 results, but otherwise empty lines full of NULs (such as produced by
87 the `xmkmf' program) will always work fine.
89 * The error messages for nonexistent included makefiles now refer to the
90 makefile name and line number where the `include' appeared, so Emacs's
91 C-x ` command takes you there (in case it's a typo you need to fix).
95 * Implicit rule search for archive member references is now done in the
96 opposite order from previous versions: the whole target name `LIB(MEM)'
97 first, and just the member name and parentheses `(MEM)' second.
99 * Make now gives an error for an unterminated variable or function reference.
100 For example, `$(foo' with no matching `)' or `${bar' with no matching `}'.
102 * The new default variable `MAKE_VERSION' gives the version number of
103 Make, and a string describing the remote job support compiled in (if any).
104 Thus the value (in this release) is something like `3.69' or `3.69-Customs'.
106 * Commands in an invocation of the `shell' function are no longer run with
107 a modified environment like target commands are. As in versions before
108 3.68, they now run with the environment that `make' started with. We
109 have reversed the change made in version 3.68 because it turned out to
110 cause a paradoxical situation in cases like:
112 export variable = $(shell echo value)
114 When Make attempted to put this variable in the environment for a target
115 command, it would try expand the value by running the shell command
116 `echo value'. In version 3.68, because it constructed an environment
117 for that shell command in the same way, Make would begin to go into an
118 infinite loop and then get a fatal error when it detected the loop.
120 * The commands given for `.DEFAULT' are now used for phony targets with no
125 * You can list several archive member names inside parenthesis:
126 `lib(mem1 mem2 mem3)' is equivalent to `lib(mem1) lib(mem2) lib(mem3)'.
128 * You can use wildcards inside archive member references. For example,
129 `lib(*.o)' expands to all existing members of `lib' whose names end in
130 `.o' (e.g. `lib(a.o) lib(b.o)'); `*.a(*.o)' expands to all such members
131 of all existing files whose names end in `.a' (e.g. `foo.a(a.o)
132 foo.a(b.o) bar.a(c.o) bar.a(d.o)'.
134 * A suffix rule `.X.a' now produces two pattern rules:
135 (%.o): %.X # Previous versions produced only this.
136 %.a: %.X # Now produces this as well, just like other suffixes.
138 * The new flag `--warn-undefined-variables' says to issue a warning message
139 whenever Make expands a reference to an undefined variable.
141 * The new `-include' directive is just like `include' except that there is
142 no error (not even a warning) for a nonexistent makefile.
144 * Commands in an invocation of the `shell' function are now run with a
145 modified environment like target commands are, so you can use `export' et
146 al to set up variables for them. They used to run with the environment
147 that `make' started with.
151 * `make --version' (or `make -v') now exits immediately after printing
156 * Make now supports long-named members in `ar' archive files.
160 * Make now supports the `+=' syntax for a variable definition which appends
161 to the variable's previous value. See the section `Appending More Text
162 to Variables' in the manual for full details.
164 * The new option `--no-print-directory' inhibits the `-w' or
165 `--print-directory' feature. Make turns on `--print-directory'
166 automatically if you use `-C' or `--directory', and in sub-makes; some
167 users have found this behavior undesirable.
169 * The built-in implicit rules now support the alternative extension
170 `.txinfo' for Texinfo files, just like `.texinfo' and `.texi'.
174 * Make now uses a standard GNU `configure' script. See the new file
175 INSTALL for the new (and much simpler) installation procedure.
177 * There is now a shell script to build Make the first time, if you have no
178 other `make' program. `build.sh' is created by `configure'; see README.
180 * GNU Make now completely conforms to the POSIX.2 specification for `make'.
182 * Elements of the `$^' and `$?' automatic variables that are archive
183 member references now list only the member name, as in Unix and POSIX.2.
185 * You should no longer ever need to specify the `-w' switch, which prints
186 the current directory before and after Make runs. The `-C' switch to
187 change directory, and recursive use of Make, now set `-w' automatically.
189 * Multiple double-colon rules for the same target will no longer have their
190 commands run simultaneously under -j, as this could result in the two
191 commands trying to change the file at the same time and interfering with
194 * The `SHELL' variable is now never taken from the environment.
195 Each makefile that wants a shell other than the default (/bin/sh) must
196 set SHELL itself. SHELL is always exported to child processes.
197 This change was made for compatibility with POSIX.2.
199 * Make now accepts long options. There is now an informative usage message
200 that tells you what all the options are and what they do. Try `make --help'.
202 * There are two new directives: `export' and `unexport'. All variables are
203 no longer automatically put into the environments of the commands that
204 Make runs. Instead, only variables specified on the command line or in
205 the environment are exported by default. To export others, use:
207 or you can define variables with:
208 export VARIABLE = VALUE
210 export VARIABLE := VALUE
214 .EXPORT_ALL_VARIABLES:
215 to get the old behavior. See the node `Variables/Recursion' in the manual
216 for a full description.
218 * The commands from the `.DEFAULT' special target are only applied to
219 targets which have no rules at all, not all targets with no commands.
220 This change was made for compatibility with Unix make.
222 * All fatal error messages now contain `***', so they are easy to find in
225 * Dependency file names like `-lNAME' are now replaced with the actual file
226 name found, as with files found by normal directory search (VPATH).
227 The library file `libNAME.a' may now be found in the current directory,
228 which is checked before VPATH; the standard set of directories (/lib,
229 /usr/lib, /usr/local/lib) is now checked last.
230 See the node `Libraries/Search' in the manual for full details.
232 * A single `include' directive can now specify more than one makefile to
235 You can also use shell file name patterns in an `include' directive:
238 * The default directories to search for included makefiles, and for
239 libraries specified with `-lNAME', are now set by configuration.
241 * You can now use blanks as well as colons to separate the directories in a
242 search path for the `vpath' directive or the `VPATH' variable.
244 * You can now use variables and functions in the left hand side of a
245 variable assignment, as in "$(foo)bar = value".
247 * The `MAKE' variable is always defined as `$(MAKE_COMMAND) $(MAKEOVERRIDES)'.
248 The `MAKE_COMMAND' variable is now defined to the name with which make
251 * The built-in rules for C++ compilation now use the variables `$(CXX)' and
252 `$(CXXFLAGS)' instead of `$(C++)' and `$(C++FLAGS)'. The old names had
253 problems with shells that cannot have `+' in environment variable names.
255 * The value of a recursively expanded variable is now expanded when putting
256 it into the environment for child processes. This change was made for
257 compatibility with Unix make.
259 * A rule with no targets before the `:' is now accepted and ignored.
260 This change was made for compatibility with SunOS 4 make.
261 We do not recommend that you write your makefiles to take advantage of this.
263 * The `-I' switch can now be used in MAKEFLAGS, and are put there
264 automatically just like other switches.
268 * Built-in rules for C++ source files with the `.C' suffix.
269 We still recommend that you use `.cc' instead.
271 * If commands are given too many times for a single target,
272 the last set given is used, and a warning message is printed.
274 * Error messages about makefiles are in standard GNU error format,
275 so C-x ` in Emacs works on them.
277 * Dependencies of pattern rules which contain no % need not actually exist
278 if they can be created (just like dependencies which do have a %).
282 * A message is always printed when Make decides there is nothing to be done.
283 It used to be that no message was printed for top-level phony targets
284 (because "`phony' is up to date" isn't quite right). Now a different
285 message "Nothing to be done for `phony'" is printed in that case.
287 * Archives on AIX now supposedly work.
289 * When the commands specified for .DEFAULT are used to update a target,
290 the $< automatic variable is given the same value as $@ for that target.
291 This is how Unix make behaves, and this behavior is mandated by POSIX.2.
295 * The -n, -q, and -t options are not put in the `MAKEFLAGS' and `MFLAG'
296 variables while remaking makefiles, so recursive makes done while remaking
297 makefiles will behave properly.
299 * If the special target `.NOEXPORT' is specified in a makefile,
300 only variables that came from the environment and variables
301 defined on the command line are exported.
305 * Suffix rules may have dependencies (which are ignored).
309 * Dependencies of the form `-lLIB' are searched for as /usr/local/lib/libLIB.a
310 as well as libLIB.a in /usr/lib, /lib, the current directory, and VPATH.
314 * There is now a Unix man page for GNU Make. It is certainly not a replacement
315 for the Texinfo manual, but it documents the basic functionality and the
316 switches. For full documentation, you should still read the Texinfo manual.
317 Thanks to Dennis Morse of Stanford University for contributing the initial
320 * Variables which are defined by default (e.g., `CC') will no longer be put
321 into the environment for child processes. (If these variables are reset by the
322 environment, makefiles, or the command line, they will still go into the
325 * Makefiles which have commands but no dependencies (and thus are always
326 considered out of date and in need of remaking), will not be remade (if they
327 were being remade only because they were makefiles). This means that GNU
328 Make will no longer go into an infinite loop when fed the makefiles that
329 `imake' (necessary to build X Windows) produces.
331 * There is no longer a warning for using the `vpath' directive with an explicit
332 pathname (instead of a `%' pattern).
336 * When removing intermediate files, only one `rm' command line is printed,
337 listing all file names.
339 * There are now automatic variables `$(^D)', `$(^F)', `$(?D)', and `$(?F)'.
340 These are the directory-only and file-only versions of `$^' and `$?'.
342 * Library dependencies given as `-lNAME' will use "libNAME.a" in the current
343 directory if it exists.
345 * The automatic variable `$($/)' is no longer defined.
347 * Leading `+' characters on a command line make that line be executed even
348 under -n, -t, or -q (as if the line contained `$(MAKE)').
350 * For command lines containing `$(MAKE)', `${MAKE}', or leading `+' characters,
351 only those lines are executed, not their entire rules.
352 (This is how Unix make behaves for lines containing `$(MAKE)' or `${MAKE}'.)
356 * Filenames in rules will now have ~ and ~USER expanded.
358 * The `-p' output has been changed so it can be used as a makefile.
359 (All information that isn't specified by makefiles is prefaced with comment
364 * The % character can be quoted with backslash in implicit pattern rules,
365 static pattern rules, `vpath' directives, and `patsubst', `filter', and
366 `filter-out' functions. A warning is issued if a `vpath' directive's
367 pattern contains no %.
369 * The `wildcard' variable expansion function now expands ~ and ~USER.
371 * Messages indicating failed commands now contain the target name:
372 make: *** [target] Error 1
374 * The `-p' output format has been changed somewhat to look more like
375 makefile rules and to give all information that Make has about files.
381 * The `-l' switch with no argument removes any previous load-average limit.
383 * When the `-w' switch is in effect, and Make has updated makefiles,
384 it will write a `Leaving directory' messagfe before re-executing itself.
385 This makes the `directory change tracking' changes to Emacs's compilation
386 commands work properly.
390 * The automatic variable `$*' is now defined for explicit rules,
391 as it is in Unix make.
395 * The `-j' switch is now put in the MAKEFLAGS and MFLAGS variables when
396 specified without an argument (indicating infinite jobs).
397 The `-l' switch is not always put in the MAKEFLAGS and MFLAGS variables.
399 * Make no longer checks hashed directories after running commands.
400 The behavior implemented in 3.41 caused too much slowdown.
404 * A dependency is NOT considered newer than its dependent if
405 they have the same modification time. The behavior implemented
406 in 3.43 conflicts with RCS.
410 * Dependency loops are no longer fatal errors.
412 * A dependency is considered newer than its dependent if
413 they have the same modification time.
417 * The variables F77 and F77FLAGS are now set by default to $(FC) and
418 $(FFLAGS). Makefiles designed for System V make may use these variables in
419 explicit rules and expect them to be set. Unfortunately, there is no way to
420 make setting these affect the Fortran implicit rules unless FC and FFLAGS
421 are not used (and these are used by BSD make).
425 * Make now checks to see if its hashed directories are changed by commands.
426 Other makes that hash directories (Sun, 4.3 BSD) don't do this.
430 * The `shell' function no longer captures standard error output.
434 * A file beginning with a dot can be the default target if it also contains
435 a slash (e.g., `../bin/foo'). (Unix make allows this as well.)
439 * Archive member names are truncated to 15 characters.
441 * Yet more USG stuff.
443 * Minimal support for Microport System V (a 16-bit machine and a
444 brain-damaged compiler). This has even lower priority than other USG
445 support, so if it gets beyond trivial, I will take it out completely.
447 * Revamped default implicit rules (not much visible change).
449 * The -d and -p options can come from the environment.
453 * Improved support for USG and HPUX (hopefully).
455 * A variable reference like `$(foo:a=b)', if `a' contains a `%', is
456 equivalent to `$(patsubst a,b,$(foo))'.
458 * Defining .DEFAULT with no deps or commands clears its commands.
460 * New default implicit rules for .S (cpp, then as), and .sh (copy and make
461 executable). All default implicit rules that use cpp (even indirectly), use
466 * Giving the -j option with no arguments gives you infinite jobs.
470 * New option: "-l LOAD" says not to start any new jobs while others are
471 running if the load average is not below LOAD (a floating-point number).
473 * There is support in place for implementations of remote command execution
474 in Make. See the file remote.c.
478 * No more than 10 directories will be kept open at once.
479 (This number can be changed by redefining MAX_OPEN_DIRECTORIES in dir.c.)
483 * Archive files will have their modification times recorded before doing
484 anything that might change their modification times by updating an archive
489 * The `MAKELEVEL' variable is defined for use by makefiles.
493 * The recursion level indications in error messages are much shorter than
494 they were in version 3.14.
498 * Leading spaces before directives are ignored (as documented).
500 * Included makefiles can determine the default goal target.
501 (System V Make does it this way, so we are being compatible).
505 * Variables that are defaults built into Make will not be put in the
506 environment for children. This just saves some environment space and,
507 except under -e, will be transparent to sub-makes.
509 * Error messages from sub-makes will indicate the level of recursion.
511 * Hopefully some speed-up for large directories due to a change in the
512 directory hashing scheme.
514 * One child will always get a standard input that is usable.
516 * Default makefiles that don't exist will be remade and read in.
520 * Count parentheses inside expansion function calls so you can
521 have nested calls: `$(sort $(foreach x,a b,$(x)))'.
525 * Several bug fixes, including USG and Sun386i support.
527 * `shell' function to expand shell commands a la `
529 * If the `-d' flag is given, version information will be printed.
531 * The `-c' option has been renamed to `-C' for compatibility with tar.
533 * The `-p' option no longer inhibits other normal operation.
535 * Makefiles will be updated and re-read if necessary.
537 * Can now run several commands at once (parallelism), -j option.
539 * Error messages will contain the level of Make recursion, if any.
541 * The `MAKEFLAGS' and `MFLAGS' variables will be scanned for options after
544 * A double-colon rule with no dependencies will always have its commands run.
545 (This is how both the BSD and System V versions of Make do it.)
549 (Changes from versions 1 through 3.05 were never recorded. Sorry.)
551 ----------------------------------------------------------------------
552 Copyright information:
554 Copyright (C) 1992, 1993, 1994, 1995, 1996 Free Software Foundation, Inc.
556 Permission is granted to anyone to make or distribute verbatim copies
557 of this document as received, in any medium, provided that the
558 copyright notice and this permission notice are preserved,
559 thus giving the recipient permission to redistribute in turn.
561 Permission is granted to distribute modified versions
562 of this document, or of portions of it,
563 under the above conditions, provided also that they
564 carry prominent notices stating who last changed them.
567 version-control: never