1 GNU make NEWS -*-indented-text-*-
2 History of user-visible changes.
5 Copyright (C) 2002,2003,2004 Free Software Foundation, Inc.
6 See the end for copying conditions.
8 All changes mentioned here are more fully described in the GNU make
9 manual, which is contained in this distribution as the file doc/make.texi.
11 Please send GNU make bug reports to <bug-make@gnu.org>.
12 See the README file and the GNU make manual for details on reporting bugs.
16 * GNU make is ported to OS/2.
17 Port provided by Andreas Buening <andreas.buening@nexgo.de>.
19 * All pattern-specific variables that match a given target are now used
20 (previously only the first match was used).
22 * Target-specific variables can be marked as exportable using the
25 * In a recursive $(call ...) context, any extra arguments from the outer
26 call are now masked in the context of the inner call.
28 * Implemented a solution for the "thundering herd" problem with "-j -l".
29 This version of GNU make uses an algorithm suggested by Thomas Riedl
30 <thomas.riedl@siemens.com> to track the number of jobs started in the
31 last second and adjust GNU make's view of the system's load average
34 * On DOS and MS Windows systems, explicitly setting SHELL to a pathname
35 ending in "cmd" or "cmd.exe" (case-insensitive) will force GNU make to
36 use the DOS command interpreter in batch mode even if a UNIX-like
37 shell could be found on the system.
39 * Enhancements for POSIX compatibility:
40 - Only touch targets (under -t) if they have at least one command.
42 * Updated to autoconf 2.59, automake 1.8.2, and gettext 0.14.1. Users
43 should not be impacted.
48 * A new feature exists: order-only prerequisites. These prerequisites
49 affect the order in which targets are built, but they do not impact
50 the rebuild/no-rebuild decision of their dependents. That is to say,
51 they allow you to require target B be built before target A, without
52 requiring that target A will always be rebuilt if target B is updated.
53 Patch for this feature provided by Greg McGary <greg@mcgary.org>.
55 * For compatibility with SysV make, GNU make now supports the peculiar
56 syntax $$@, $$(@D), and $$(@F) in the prerequisites list of a rule.
57 This syntax is only valid within explicit and static pattern rules: it
58 cannot be used in implicit (suffix or pattern) rules. Edouard G. Parmelan
59 <egp@free.fr> provided a patch implementing this feature; however, I
60 decided to implement it in a different way.
62 * The argument to the "ifdef" conditional is now expanded before it's
63 tested, so it can be a constructed variable name.
65 Similarly, the arguments to "export" (when not used in a variable
66 definition context) and "unexport" are also now expanded.
68 * A new function is defined: $(value ...). The argument to this
69 function is the _name_ of a variable. The result of the function is
70 the value of the variable, without having been expanded.
72 * A new function is defined: $(eval ...). The arguments to this
73 function should expand to makefile commands, which will then be
74 evaluated as if they had appeared in the makefile. In combination
75 with define/endef multiline variable definitions this is an extremely
76 powerful capability. The $(value ...) function is also sometimes
79 * A new built-in variable is defined, $(MAKEFILE_LIST). It contains a
80 list of each makefile GNU make has read, or started to read, in the
81 order in which they were encountered. So, the last filename in the
82 list when a makefile is just being read (before any includes) is the
83 name of the current makefile.
85 * A new built-in variable is defined: $(.VARIABLES). When it is
86 expanded it returns a complete list of variable names defined by all
87 makefiles at that moment.
89 * A new command-line option is defined, -B or --always-make. If
90 specified GNU make will consider all targets out-of-date even if they
91 would otherwise not be.
93 * The arguments to $(call ...) functions were being stored in $1, $2,
94 etc. as recursive variables, even though they are fully expanded
95 before assignment. This means that escaped dollar signs ($$ etc.)
96 were not behaving properly. Now the arguments are stored as simple
97 variables. This may mean that if you added extra escaping to your
98 $(call ...) function arguments you will need to undo it now.
100 * The variable invoked by $(call ...) can now be recursive: unlike other
101 variables it can reference itself and this will not produce an error
102 when it is used as the first argument to $(call ...) (but only then).
104 * New pseudo-target .LOW_RESOLUTION_TIME, superseding the configure
105 option --disable-nsec-timestamps. You might need this if your build
106 process depends on tools like "cp -p" preserving time stamps, since
107 "cp -p" (right now) doesn't preserve the subsecond portion of a time
110 * Updated translations for French, Galician, German, Japanese, Korean,
111 and Russian. New translations for Croatian, Danish, Hebrew, and
114 * Updated internationalization support to Gettext 0.11.5.
115 GNU make now uses Gettext's "external" feature, and does not include
116 any internationalization code itself. Configure will search your
117 system for an existing implementation of GNU Gettext (only GNU Gettext
118 is acceptable) and use it if it exists. If not, NLS will be disabled.
119 See ABOUT-NLS for more information.
121 * Updated to autoconf 2.54 and automake 1.7. Users should not be impacted.
125 * .SECONDARY with no prerequisites now prevents any target from being
126 removed because make thinks it's an intermediate file, not just those
127 listed in the makefile.
129 * New configure option --disable-nsec-timestamps, but this was
130 superseded in later versions by the .LOW_RESOLUTION_TIME pseudo-target.
134 * GNU make optionally supports internationalization and locales via the
135 GNU gettext (or local gettext if suitable) package. See the ABOUT-NLS
136 file for more information on configuring GNU make for NLS.
138 * Previously, GNU make quoted variables such as MAKEFLAGS and
139 MAKEOVERRIDES for proper parsing by the shell. This allowed them to
140 be used within make build scripts. However, using them there is not
141 proper behavior: they are meant to be passed to subshells via the
142 environment. Unfortunately the values were not quoted properly to be
143 passed through the environment. This meant that make didn't properly
144 pass some types of command line values to submakes.
146 With this version we change that behavior: now these variables are
147 quoted properly for passing through the environment, which is the
148 correct way to do it. If you previously used these variables
149 explicitly within a make rule you may need to re-examine your use for
150 correctness given this change.
152 * A new pseudo-target .NOTPARALLEL is available. If defined, the
153 current makefile is run serially regardless of the value of -j.
154 However, submakes are still eligible for parallel execution.
156 * The --debug option has changed: it now allows optional flags
157 controlling the amount and type of debugging output. By default only
158 a minimal amount information is generated, displaying the names of
159 "normal" targets (not makefiles) that were deemed out of date and in
160 need of being rebuilt.
162 Note that the -d option behaves as before: it takes no arguments and
163 all debugging information is generated.
165 * The `-p' (print database) output now includes filename and linenumber
166 information for variable definitions, to aid debugging.
168 * The wordlist function no longer reverses its arguments if the "start"
169 value is greater than the "end" value. If that's true, nothing is
172 * Hartmut Becker provided many updates for the VMS port of GNU make.
173 See the readme.vms file for more details.
177 * Two new functions, $(error ...) and $(warning ...) are available. The
178 former will cause make to fail and exit immediately upon expansion of
179 the function, with the text provided as the error message. The latter
180 causes the text provided to be printed as a warning message, but make
183 * A new function $(call ...) is available. This allows users to create
184 their own parameterized macros and invoke them later. Original
185 implementation of this function was provided by Han-Wen Nienhuys
188 * A new function $(if ...) is available. It provides if-then-else
189 capabilities in a builtin function. Original implementation of this
190 function was provided by Han-Wen Nienhuys <hanwen@cs.uu.nl>.
192 * Make defines a new variable, .LIBPATTERNS. This variable controls how
193 library dependency expansion (dependencies like ``-lfoo'') is performed.
195 * Make accepts CRLF sequences as well as traditional LF, for
196 compatibility with makefiles created on other operating systems.
198 * Make accepts a new option: -R, or --no-builtin-variables. This option
199 disables the definition of the rule-specific builtin variables (CC,
200 LD, AR, etc.). Specifying this option forces -r (--no-builtin-rules)
203 * A "job server" feature, suggested by Howard Chu <hyc@highlandsun.com>.
205 On systems that support POSIX pipe(2) semantics, GNU make can now pass
206 -jN options to submakes rather than forcing them all to use -j1. The
207 top make and all its sub-make processes use a pipe to communicate with
208 each other to ensure that no more than N jobs are started across all
209 makes. To get the old behavior of -j back, you can configure make
210 with the --disable-job-server option.
212 * The confusing term "dependency" has been replaced by the more accurate
213 and standard term "prerequisite", both in the manual and in all GNU make
216 * GNU make supports the "big archive" library format introduced in AIX 4.3.
218 * GNU make supports large files on AIX, HP-UX, and IRIX. These changes
219 were provided by Paul Eggert <eggert@twinsun.com>. (Large file
220 support for Solaris and Linux was introduced in 3.77, but the
221 configuration had issues: these have also been resolved).
223 * The Windows 95/98/NT (W32) version of GNU make now has native support
224 for the Cygnus Cygwin release B20.1 shell (bash).
226 * The GNU make regression test suite, long available separately "under
227 the table", has been integrated into the release. You can invoke it
228 by running "make check" in the distribution. Note that it requires
229 Perl (either Perl 4 or Perl 5) to run.
233 * Implement BSD make's "?=" variable assignment operator. The variable
234 is assigned the specified value only if that variable is not already
237 * Make defines a new variable, "CURDIR", to contain the current working
238 directory (after the -C option, if any, has been processed).
239 Modifying this variable has no effect on the operation of make.
241 * Make defines a new default RCS rule, for new-style master file
242 storage: ``% :: RCS/%'' (note no ``,v'' suffix).
244 Make defines new default rules for DOS-style C++ file naming
245 conventions, with ``.cpp'' suffixes. All the same rules as for
246 ``.cc'' and ``.C'' suffixes are provided, along with LINK.cpp and
247 COMPILE.cpp macros (which default to the same value as LINK.cc and
248 COMPILE.cc). Note CPPFLAGS is still C preprocessor flags! You should
249 use CXXFLAGS to change C++ compiler flags.
251 * A new feature, "target-specific variable values", has been added.
252 This is a large change so please see the appropriate sections of the
253 manual for full details. Briefly, syntax like this:
255 TARGET: VARIABLE = VALUE
257 defines VARIABLE as VALUE within the context of TARGET. This is
258 similar to SunOS make's "TARGET := VARIABLE = VALUE" feature. Note
259 that the assignment may be of any type, not just recursive, and that
260 the override keyword is available.
262 COMPATIBILITY: This new syntax means that if you have any rules where
263 the first or second dependency has an equal sign (=) in its name,
264 you'll have to escape them with a backslash: "foo : bar\=baz".
265 Further, if you have any dependencies which already contain "\=",
266 you'll have to escape both of them: "foo : bar\\\=baz".
268 * A new appendix listing the most common error and warning messages
269 generated by GNU make, with some explanation, has been added to the
270 GNU make User's Manual.
272 * Updates to the GNU make Customs library support (see README.customs).
274 * Updates to the Windows 95/NT port from Rob Tulloh (see README.W32),
275 and to the DOS port from Eli Zaretski (see README.DOS).
279 * Small (but serious) bug fix. Quick rollout to get into the GNU source CD.
283 * GNU make now uses automake to control Makefile.in generation. This
284 should make it more consistent with the GNU standards.
286 * VPATH functionality has been changed to incorporate the VPATH+ patch,
287 previously maintained by Paul Smith <psmith@baynetworks.com>. See the
290 * Make defines a new variable, `MAKECMDGOALS', to contain the goals that
291 were specified on the command line, if any. Modifying this variable
292 has no effect on the operation of make.
294 * A new function, `$(wordlist S,E,TEXT)', is available: it returns a
295 list of words from number S to number E (inclusive) of TEXT.
297 * Instead of an error, detection of future modification times gives a
298 warning and continues. The warning is repeated just before GNU make
299 exits, so it is less likely to be lost.
301 * Fix the $(basename) and $(suffix) functions so they only operate on
302 the last filename, not the entire string:
304 Command Old Result New Result
305 ------- ---------- ----------
307 $(basename a.b/c) a a.b/c
309 $(suffix a.b/c) b/c <empty>
311 * The $(strip) function now removes newlines as well as TABs and spaces.
313 * The $(shell) function now changes CRLF (\r\n) pairs to a space as well
316 * Updates to the Windows 95/NT port from Rob Tulloh (see README.W32).
318 * Eli Zaretskii has updated the port to 32-bit protected mode on MSDOS
319 and MS-Windows, building with the DJGPP v2 port of GNU C/C++ compiler
320 and utilities. See README.DOS for details, and direct all questions
321 concerning this port to Eli Zaretskii <eliz@is.elta.co.il> or DJ
322 Delorie <dj@delorie.com>.
324 * John W. Eaton has updated the VMS port to support libraries and VPATH.
328 * The directory messages printed by `-w' and implicitly in sub-makes,
329 are now omitted if Make runs no commands and has no other messages to print.
331 * Make now detects files that for whatever reason have modification times
332 in the future and gives an error. Files with such impossible timestamps
333 can result from unsynchronized clocks, or archived distributions
334 containing bogus timestamps; they confuse Make's dependency engine
337 * The new directive `sinclude' is now recognized as another name for
338 `-include', for compatibility with some other Makes.
340 * Aaron Digulla has contributed a port to AmigaDOS. See README.Amiga for
341 details, and direct all Amiga-related questions to <digulla@fh-konstanz.de>.
343 * Rob Tulloh of Tivoli Systems has contributed a port to Windows NT or 95.
344 See README.W32 for details, and direct all Windows-related questions to
345 <rob_tulloh@tivoli.com>.
349 * Converted to use Autoconf version 2, so `configure' has some new options.
350 See INSTALL for details.
352 * You can now send a SIGUSR1 signal to Make to toggle printing of debugging
353 output enabled by -d, at any time during the run.
357 * DJ Delorie has ported Make to MS-DOS using the GO32 extender.
358 He is maintaining the DOS port, not the GNU Make maintainer;
359 please direct bugs and questions for DOS to <djgpp@sun.soe.clarkson.edu>.
360 MS-DOS binaries are available for FTP from ftp.simtel.net in
361 /pub/simtelnet/gnu/djgpp/.
363 * The `MAKEFLAGS' variable (in the environment or in a makefile) can now
364 contain variable definitions itself; these are treated just like
365 command-line variable definitions. Make will automatically insert any
366 variable definitions from the environment value of `MAKEFLAGS' or from
367 the command line, into the `MAKEFLAGS' value exported to children. The
368 `MAKEOVERRIDES' variable previously included in the value of `$(MAKE)'
369 for sub-makes is now included in `MAKEFLAGS' instead. As before, you can
370 reset `MAKEOVERRIDES' in your makefile to avoid putting all the variables
371 in the environment when its size is limited.
373 * If `.DELETE_ON_ERROR' appears as a target, Make will delete the target of
374 a rule if it has changed when its commands exit with a nonzero status,
375 just as when the commands get a signal.
377 * The automatic variable `$+' is new. It lists all the dependencies like
378 `$^', but preserves duplicates listed in the makefile. This is useful
379 for linking rules, where library files sometimes need to be listed twice
382 * You can now specify the `.IGNORE' and `.SILENT' special targets with
383 dependencies to limit their effects to those files. If a file appears as
384 a dependency of `.IGNORE', then errors will be ignored while running the
385 commands to update that file. Likewise if a file appears as a dependency
386 of `.SILENT', then the commands to update that file will not be printed
387 before they are run. (This change was made to conform to POSIX.2.)
391 * The automatic variables `$(@D)', `$(%D)', `$(*D)', `$(<D)', `$(?D)', and
392 `$(^D)' now omit the trailing slash from the directory name. (This change
393 was made to comply with POSIX.2.)
395 * The source distribution now includes the Info files for the Make manual.
396 There is no longer a separate distribution containing Info and DVI files.
398 * You can now set the variables `binprefix' and/or `manprefix' in
399 Makefile.in (or on the command line when installing) to install GNU make
400 under a name other than `make' (i.e., ``make binprefix=g install''
401 installs GNU make as `gmake').
403 * The built-in Texinfo rules use the new variables `TEXI2DVI_FLAGS' for
404 flags to the `texi2dvi' script, and `MAKEINFO_FLAGS' for flags to the
407 * The exit status of Make when it runs into errors is now 2 instead of 1.
408 The exit status is 1 only when using -q and some target is not up to date.
409 (This change was made to comply with POSIX.2.)
413 * It is no longer a fatal error to have a NUL character in a makefile.
414 You should never put a NUL in a makefile because it can have strange
415 results, but otherwise empty lines full of NULs (such as produced by
416 the `xmkmf' program) will always work fine.
418 * The error messages for nonexistent included makefiles now refer to the
419 makefile name and line number where the `include' appeared, so Emacs's
420 C-x ` command takes you there (in case it's a typo you need to fix).
424 * Implicit rule search for archive member references is now done in the
425 opposite order from previous versions: the whole target name `LIB(MEM)'
426 first, and just the member name and parentheses `(MEM)' second.
428 * Make now gives an error for an unterminated variable or function reference.
429 For example, `$(foo' with no matching `)' or `${bar' with no matching `}'.
431 * The new default variable `MAKE_VERSION' gives the version number of
432 Make, and a string describing the remote job support compiled in (if any).
433 Thus the value (in this release) is something like `3.69' or `3.69-Customs'.
435 * Commands in an invocation of the `shell' function are no longer run with
436 a modified environment like target commands are. As in versions before
437 3.68, they now run with the environment that `make' started with. We
438 have reversed the change made in version 3.68 because it turned out to
439 cause a paradoxical situation in cases like:
441 export variable = $(shell echo value)
443 When Make attempted to put this variable in the environment for a target
444 command, it would try expand the value by running the shell command
445 `echo value'. In version 3.68, because it constructed an environment
446 for that shell command in the same way, Make would begin to go into an
447 infinite loop and then get a fatal error when it detected the loop.
449 * The commands given for `.DEFAULT' are now used for phony targets with no
454 * You can list several archive member names inside parenthesis:
455 `lib(mem1 mem2 mem3)' is equivalent to `lib(mem1) lib(mem2) lib(mem3)'.
457 * You can use wildcards inside archive member references. For example,
458 `lib(*.o)' expands to all existing members of `lib' whose names end in
459 `.o' (e.g. `lib(a.o) lib(b.o)'); `*.a(*.o)' expands to all such members
460 of all existing files whose names end in `.a' (e.g. `foo.a(a.o)
461 foo.a(b.o) bar.a(c.o) bar.a(d.o)'.
463 * A suffix rule `.X.a' now produces two pattern rules:
464 (%.o): %.X # Previous versions produced only this.
465 %.a: %.X # Now produces this as well, just like other suffixes.
467 * The new flag `--warn-undefined-variables' says to issue a warning message
468 whenever Make expands a reference to an undefined variable.
470 * The new `-include' directive is just like `include' except that there is
471 no error (not even a warning) for a nonexistent makefile.
473 * Commands in an invocation of the `shell' function are now run with a
474 modified environment like target commands are, so you can use `export' et
475 al to set up variables for them. They used to run with the environment
476 that `make' started with.
480 * `make --version' (or `make -v') now exits immediately after printing
485 * Make now supports long-named members in `ar' archive files.
489 * Make now supports the `+=' syntax for a variable definition which appends
490 to the variable's previous value. See the section `Appending More Text
491 to Variables' in the manual for full details.
493 * The new option `--no-print-directory' inhibits the `-w' or
494 `--print-directory' feature. Make turns on `--print-directory'
495 automatically if you use `-C' or `--directory', and in sub-makes; some
496 users have found this behavior undesirable.
498 * The built-in implicit rules now support the alternative extension
499 `.txinfo' for Texinfo files, just like `.texinfo' and `.texi'.
503 * Make now uses a standard GNU `configure' script. See the new file
504 INSTALL for the new (and much simpler) installation procedure.
506 * There is now a shell script to build Make the first time, if you have no
507 other `make' program. `build.sh' is created by `configure'; see README.
509 * GNU Make now completely conforms to the POSIX.2 specification for `make'.
511 * Elements of the `$^' and `$?' automatic variables that are archive
512 member references now list only the member name, as in Unix and POSIX.2.
514 * You should no longer ever need to specify the `-w' switch, which prints
515 the current directory before and after Make runs. The `-C' switch to
516 change directory, and recursive use of Make, now set `-w' automatically.
518 * Multiple double-colon rules for the same target will no longer have their
519 commands run simultaneously under -j, as this could result in the two
520 commands trying to change the file at the same time and interfering with
523 * The `SHELL' variable is now never taken from the environment.
524 Each makefile that wants a shell other than the default (/bin/sh) must
525 set SHELL itself. SHELL is always exported to child processes.
526 This change was made for compatibility with POSIX.2.
528 * Make now accepts long options. There is now an informative usage message
529 that tells you what all the options are and what they do. Try `make --help'.
531 * There are two new directives: `export' and `unexport'. All variables are
532 no longer automatically put into the environments of the commands that
533 Make runs. Instead, only variables specified on the command line or in
534 the environment are exported by default. To export others, use:
536 or you can define variables with:
537 export VARIABLE = VALUE
539 export VARIABLE := VALUE
543 .EXPORT_ALL_VARIABLES:
544 to get the old behavior. See the node `Variables/Recursion' in the manual
545 for a full description.
547 * The commands from the `.DEFAULT' special target are only applied to
548 targets which have no rules at all, not all targets with no commands.
549 This change was made for compatibility with Unix make.
551 * All fatal error messages now contain `***', so they are easy to find in
554 * Dependency file names like `-lNAME' are now replaced with the actual file
555 name found, as with files found by normal directory search (VPATH).
556 The library file `libNAME.a' may now be found in the current directory,
557 which is checked before VPATH; the standard set of directories (/lib,
558 /usr/lib, /usr/local/lib) is now checked last.
559 See the node `Libraries/Search' in the manual for full details.
561 * A single `include' directive can now specify more than one makefile to
564 You can also use shell file name patterns in an `include' directive:
567 * The default directories to search for included makefiles, and for
568 libraries specified with `-lNAME', are now set by configuration.
570 * You can now use blanks as well as colons to separate the directories in a
571 search path for the `vpath' directive or the `VPATH' variable.
573 * You can now use variables and functions in the left hand side of a
574 variable assignment, as in "$(foo)bar = value".
576 * The `MAKE' variable is always defined as `$(MAKE_COMMAND) $(MAKEOVERRIDES)'.
577 The `MAKE_COMMAND' variable is now defined to the name with which make
580 * The built-in rules for C++ compilation now use the variables `$(CXX)' and
581 `$(CXXFLAGS)' instead of `$(C++)' and `$(C++FLAGS)'. The old names had
582 problems with shells that cannot have `+' in environment variable names.
584 * The value of a recursively expanded variable is now expanded when putting
585 it into the environment for child processes. This change was made for
586 compatibility with Unix make.
588 * A rule with no targets before the `:' is now accepted and ignored.
589 This change was made for compatibility with SunOS 4 make.
590 We do not recommend that you write your makefiles to take advantage of this.
592 * The `-I' switch can now be used in MAKEFLAGS, and are put there
593 automatically just like other switches.
597 * Built-in rules for C++ source files with the `.C' suffix.
598 We still recommend that you use `.cc' instead.
600 * If commands are given too many times for a single target,
601 the last set given is used, and a warning message is printed.
603 * Error messages about makefiles are in standard GNU error format,
604 so C-x ` in Emacs works on them.
606 * Dependencies of pattern rules which contain no % need not actually exist
607 if they can be created (just like dependencies which do have a %).
611 * A message is always printed when Make decides there is nothing to be done.
612 It used to be that no message was printed for top-level phony targets
613 (because "`phony' is up to date" isn't quite right). Now a different
614 message "Nothing to be done for `phony'" is printed in that case.
616 * Archives on AIX now supposedly work.
618 * When the commands specified for .DEFAULT are used to update a target,
619 the $< automatic variable is given the same value as $@ for that target.
620 This is how Unix make behaves, and this behavior is mandated by POSIX.2.
624 * The -n, -q, and -t options are not put in the `MAKEFLAGS' and `MFLAG'
625 variables while remaking makefiles, so recursive makes done while remaking
626 makefiles will behave properly.
628 * If the special target `.NOEXPORT' is specified in a makefile,
629 only variables that came from the environment and variables
630 defined on the command line are exported.
634 * Suffix rules may have dependencies (which are ignored).
638 * Dependencies of the form `-lLIB' are searched for as /usr/local/lib/libLIB.a
639 as well as libLIB.a in /usr/lib, /lib, the current directory, and VPATH.
643 * There is now a Unix man page for GNU Make. It is certainly not a replacement
644 for the Texinfo manual, but it documents the basic functionality and the
645 switches. For full documentation, you should still read the Texinfo manual.
646 Thanks to Dennis Morse of Stanford University for contributing the initial
649 * Variables which are defined by default (e.g., `CC') will no longer be put
650 into the environment for child processes. (If these variables are reset by the
651 environment, makefiles, or the command line, they will still go into the
654 * Makefiles which have commands but no dependencies (and thus are always
655 considered out of date and in need of remaking), will not be remade (if they
656 were being remade only because they were makefiles). This means that GNU
657 Make will no longer go into an infinite loop when fed the makefiles that
658 `imake' (necessary to build X Windows) produces.
660 * There is no longer a warning for using the `vpath' directive with an explicit
661 pathname (instead of a `%' pattern).
665 * When removing intermediate files, only one `rm' command line is printed,
666 listing all file names.
668 * There are now automatic variables `$(^D)', `$(^F)', `$(?D)', and `$(?F)'.
669 These are the directory-only and file-only versions of `$^' and `$?'.
671 * Library dependencies given as `-lNAME' will use "libNAME.a" in the current
672 directory if it exists.
674 * The automatic variable `$($/)' is no longer defined.
676 * Leading `+' characters on a command line make that line be executed even
677 under -n, -t, or -q (as if the line contained `$(MAKE)').
679 * For command lines containing `$(MAKE)', `${MAKE}', or leading `+' characters,
680 only those lines are executed, not their entire rules.
681 (This is how Unix make behaves for lines containing `$(MAKE)' or `${MAKE}'.)
685 * Filenames in rules will now have ~ and ~USER expanded.
687 * The `-p' output has been changed so it can be used as a makefile.
688 (All information that isn't specified by makefiles is prefaced with comment
693 * The % character can be quoted with backslash in implicit pattern rules,
694 static pattern rules, `vpath' directives, and `patsubst', `filter', and
695 `filter-out' functions. A warning is issued if a `vpath' directive's
696 pattern contains no %.
698 * The `wildcard' variable expansion function now expands ~ and ~USER.
700 * Messages indicating failed commands now contain the target name:
701 make: *** [target] Error 1
703 * The `-p' output format has been changed somewhat to look more like
704 makefile rules and to give all information that Make has about files.
710 * The `-l' switch with no argument removes any previous load-average limit.
712 * When the `-w' switch is in effect, and Make has updated makefiles,
713 it will write a `Leaving directory' messagfe before re-executing itself.
714 This makes the `directory change tracking' changes to Emacs's compilation
715 commands work properly.
719 * The automatic variable `$*' is now defined for explicit rules,
720 as it is in Unix make.
724 * The `-j' switch is now put in the MAKEFLAGS and MFLAGS variables when
725 specified without an argument (indicating infinite jobs).
726 The `-l' switch is not always put in the MAKEFLAGS and MFLAGS variables.
728 * Make no longer checks hashed directories after running commands.
729 The behavior implemented in 3.41 caused too much slowdown.
733 * A dependency is NOT considered newer than its dependent if
734 they have the same modification time. The behavior implemented
735 in 3.43 conflicts with RCS.
739 * Dependency loops are no longer fatal errors.
741 * A dependency is considered newer than its dependent if
742 they have the same modification time.
746 * The variables F77 and F77FLAGS are now set by default to $(FC) and
747 $(FFLAGS). Makefiles designed for System V make may use these variables in
748 explicit rules and expect them to be set. Unfortunately, there is no way to
749 make setting these affect the Fortran implicit rules unless FC and FFLAGS
750 are not used (and these are used by BSD make).
754 * Make now checks to see if its hashed directories are changed by commands.
755 Other makes that hash directories (Sun, 4.3 BSD) don't do this.
759 * The `shell' function no longer captures standard error output.
763 * A file beginning with a dot can be the default target if it also contains
764 a slash (e.g., `../bin/foo'). (Unix make allows this as well.)
768 * Archive member names are truncated to 15 characters.
770 * Yet more USG stuff.
772 * Minimal support for Microport System V (a 16-bit machine and a
773 brain-damaged compiler). This has even lower priority than other USG
774 support, so if it gets beyond trivial, I will take it out completely.
776 * Revamped default implicit rules (not much visible change).
778 * The -d and -p options can come from the environment.
782 * Improved support for USG and HPUX (hopefully).
784 * A variable reference like `$(foo:a=b)', if `a' contains a `%', is
785 equivalent to `$(patsubst a,b,$(foo))'.
787 * Defining .DEFAULT with no deps or commands clears its commands.
789 * New default implicit rules for .S (cpp, then as), and .sh (copy and make
790 executable). All default implicit rules that use cpp (even indirectly), use
795 * Giving the -j option with no arguments gives you infinite jobs.
799 * New option: "-l LOAD" says not to start any new jobs while others are
800 running if the load average is not below LOAD (a floating-point number).
802 * There is support in place for implementations of remote command execution
803 in Make. See the file remote.c.
807 * No more than 10 directories will be kept open at once.
808 (This number can be changed by redefining MAX_OPEN_DIRECTORIES in dir.c.)
812 * Archive files will have their modification times recorded before doing
813 anything that might change their modification times by updating an archive
818 * The `MAKELEVEL' variable is defined for use by makefiles.
822 * The recursion level indications in error messages are much shorter than
823 they were in version 3.14.
827 * Leading spaces before directives are ignored (as documented).
829 * Included makefiles can determine the default goal target.
830 (System V Make does it this way, so we are being compatible).
834 * Variables that are defaults built into Make will not be put in the
835 environment for children. This just saves some environment space and,
836 except under -e, will be transparent to sub-makes.
838 * Error messages from sub-makes will indicate the level of recursion.
840 * Hopefully some speed-up for large directories due to a change in the
841 directory hashing scheme.
843 * One child will always get a standard input that is usable.
845 * Default makefiles that don't exist will be remade and read in.
849 * Count parentheses inside expansion function calls so you can
850 have nested calls: `$(sort $(foreach x,a b,$(x)))'.
854 * Several bug fixes, including USG and Sun386i support.
856 * `shell' function to expand shell commands a la `
858 * If the `-d' flag is given, version information will be printed.
860 * The `-c' option has been renamed to `-C' for compatibility with tar.
862 * The `-p' option no longer inhibits other normal operation.
864 * Makefiles will be updated and re-read if necessary.
866 * Can now run several commands at once (parallelism), -j option.
868 * Error messages will contain the level of Make recursion, if any.
870 * The `MAKEFLAGS' and `MFLAGS' variables will be scanned for options after
873 * A double-colon rule with no dependencies will always have its commands run.
874 (This is how both the BSD and System V versions of Make do it.)
878 (Changes from versions 1 through 3.05 were never recorded. Sorry.)
880 ----------------------------------------------------------------------
881 Copyright information:
883 Permission is granted to anyone to make or distribute verbatim copies
884 of this document as received, in any medium, provided that the
885 copyright notice and this permission notice are preserved, thus
886 giving the recipient permission to redistribute in turn.
888 Permission is granted to distribute modified versions of this
889 document, or of portions of it, under the above conditions, provided
890 also that they carry prominent notices stating who last changed them.