1 GNU make NEWS -*-indented-text-*-
2 History of user-visible changes.
5 See the end of this file for copyrights and conditions.
7 All changes mentioned here are more fully described in the GNU make
8 manual, which is contained in this distribution as the file doc/make.texi.
9 See the README file and the GNU make manual for instructions for
14 A complete list of bugs fixed in this version is available here:
16 http://sv.gnu.org/bugs/index.php?group=make&report_id=111&fix_release_id=104&set=custom
18 * Compiling GNU make now requires a conforming ISO C 1989 compiler and
19 standard runtime library.
21 * WARNING: Future backward-incompatibility!
22 Wildcards are not documented as returning sorted values, but up to and
23 including this release the results have been sorted and some makefiles are
24 apparently depending on that. In the next release of GNU make, for
25 performance reasons, we may remove that sorting. If your makefiles
26 require sorted results from wildcard expansions, use the $(sort ...)
27 function to request it explicitly.
29 * WARNING: Backward-incompatibility!
30 The POSIX standard for make was changed in the 2008 version in a
31 fundamentally incompatible way: make is required to invoke the shell as if
32 the '-e' flag were provided. Because this would break many makefiles that
33 have been written to conform to the original text of the standard, the
34 default behavior of GNU make remains to invoke the shell with simply '-c'.
35 However, any makefile specifying the .POSIX special target will follow the
36 new POSIX standard and pass '-e' to the shell. See also .SHELLFLAGS
39 * WARNING: Backward-incompatibility!
40 The '$?' variable now contains all prerequisites that caused the target to
41 be considered out of date, even if they do not exist (previously only
42 existing targets were provided in $?).
44 * WARNING: Backward-incompatibility!
45 As a result of parser enhancements, three backward-compatibility issues
46 exist: first, a prerequisite containing an "=" cannot be escaped with a
47 backslash any longer. You must create a variable containing an "=" and
48 use that variable in the prerequisite. Second, variable names can no
49 longer contain whitespace, unless you put the whitespace in a variable and
50 use the variable. Third, in previous versions of make it was sometimes
51 not flagged as an error for explicit and pattern targets to appear in the
52 same rule. Now this is always reported as an error.
54 * WARNING: Backward-incompatibility!
55 The pattern-specific variables and pattern rules are now applied in the
56 shortest stem first order instead of the definition order (variables
57 and rules with the same stem length are still applied in the definition
58 order). This produces the usually-desired behavior where more specific
59 patterns are preferred. To detect this feature search for 'shortest-stem'
60 in the .FEATURES special variable.
62 * WARNING: Backward-incompatibility!
63 The library search behavior has changed to be compatible with the standard
64 linker behavior. Prior to this version for prerequisites specified using
65 the -lfoo syntax make first searched for libfoo.so in the current
66 directory, vpath directories, and system directories. If that didn't yield
67 a match, make then searched for libfoo.a in these directories. Starting
68 with this version make searches first for libfoo.so and then for libfoo.a
69 in each of these directories in order.
71 * New command line option: --eval=STRING causes STRING to be evaluated as
72 makefile syntax (akin to using the $(eval ...) function). The evaluation
73 is performed after all default rules and variables are defined, but before
74 any makefiles are read.
76 * New special variable: .RECIPEPREFIX allows you to reset the recipe
77 introduction character from the default (TAB) to something else. The
78 first character of this variable value is the new recipe introduction
79 character. If the variable is set to the empty string, TAB is used again.
80 It can be set and reset at will; recipes will use the value active when
81 they were first parsed. To detect this feature check the value of
84 * New special variable: .SHELLFLAGS allows you to change the options passed
85 to the shell when it invokes recipes. By default the value will be "-c"
86 (or "-ec" if .POSIX is set).
88 * New special target: .ONESHELL instructs make to invoke a single instance
89 of the shell and provide it with the entire recipe, regardless of how many
90 lines it contains. As a special feature to allow more straightforward
91 conversion of makefiles to use .ONESHELL, any recipe line control
92 characters ('@', '+', or '-') will be removed from the second and
93 subsequent recipe lines. This happens _only_ if the SHELL value is deemed
94 to be a standard POSIX-style shell. If not, then no interior line control
95 characters are removed (as they may be part of the scripting language used
96 with the alternate SHELL).
98 * New variable modifier 'private': prefixing a variable assignment with the
99 modifier 'private' suppresses inheritance of that variable by
100 prerequisites. This is most useful for target- and pattern-specific
103 * New make directive: 'undefine' allows you to undefine a variable so that
104 it appears as if it was never set. Both $(flavor) and $(origin) functions
105 will return 'undefined' for such a variable. To detect this feature search
106 for 'undefine' in the .FEATURES special variable.
108 * The parser for variable assignments has been enhanced to allow multiple
109 modifiers ('export', 'override', 'private') on the same line as variables,
110 including define/endef variables, and in any order. Also, it is possible
111 to create variables and targets named as these modifiers.
113 * The 'define' make directive now allows a variable assignment operator
114 after the variable name, to allow for simple, conditional, or appending
115 multi-line variable assignment.
120 * GNU make is ported to OS/2.
122 * GNU make is ported to MinGW. The MinGW build is only supported by
123 the build_w32.bat batch file; see the file README.W32 for more
126 * WARNING: Future backward-incompatibility!
127 Up to and including this release, the '$?' variable does not contain
128 any prerequisite that does not exist, even though that prerequisite
129 might have caused the target to rebuild. Starting with the _next_
130 release of GNU make, '$?' will contain all prerequisites that caused
131 the target to be considered out of date. See this Savannah bug:
132 http://savannah.gnu.org/bugs/index.php?func=detailitem&item_id=16051
134 * WARNING: Backward-incompatibility!
135 GNU make now implements a generic "second expansion" feature on the
136 prerequisites of both explicit and implicit (pattern) rules. In order
137 to enable this feature, the special target '.SECONDEXPANSION' must be
138 defined before the first target which takes advantage of it. If this
139 feature is enabled then after all rules have been parsed the
140 prerequisites are expanded again, this time with all the automatic
141 variables in scope. This means that in addition to using standard
142 SysV $$@ in prerequisites lists, you can also use complex functions
143 such as $$(notdir $$@) etc. This behavior applies to implicit rules,
144 as well, where the second expansion occurs when the rule is matched.
145 However, this means that when '.SECONDEXPANSION' is enabled you must
146 double-quote any "$" in your filenames; instead of "foo: boo$$bar" you
147 now must write "foo: foo$$$$bar". Note that the SysV $$@ etc. feature,
148 which used to be available by default, is now ONLY available when the
149 .SECONDEXPANSION target is defined. If your makefiles take advantage
150 of this SysV feature you will need to update them.
152 * WARNING: Backward-incompatibility!
153 In order to comply with POSIX, the way in which GNU make processes
154 backslash-newline sequences in recipes has changed. If your makefiles
155 use backslash-newline sequences inside of single-quoted strings in
156 recipes you will be impacted by this change. See the GNU make manual
157 subsection "Splitting Recipe Lines" (node "Splitting Lines"), in
158 section "Recipe Syntax", chapter "Writing Recipe in Rules", for
161 * WARNING: Backward-incompatibility!
162 Some previous versions of GNU make had a bug where "#" in a function
163 invocation such as $(shell ...) was treated as a make comment. A
164 workaround was to escape these with backslashes. This bug has been
165 fixed: if your makefile uses "\#" in a function invocation the
166 backslash is now preserved, so you'll need to remove it.
168 * New command line option: -L (--check-symlink-times). On systems that
169 support symbolic links, if this option is given then GNU make will
170 use the most recent modification time of any symbolic links that are
171 used to resolve target files. The default behavior remains as it
172 always has: use the modification time of the actual target file only.
174 * The "else" conditional line can now be followed by any other valid
175 conditional on the same line: this does not increase the depth of the
176 conditional nesting, so only one "endif" is required to close the
179 * All pattern-specific variables that match a given target are now used
180 (previously only the first match was used).
182 * Target-specific variables can be marked as exportable using the
185 * In a recursive $(call ...) context, any extra arguments from the outer
186 call are now masked in the context of the inner call.
188 * Implemented a solution for the "thundering herd" problem with "-j -l".
189 This version of GNU make uses an algorithm suggested by Thomas Riedl
190 <thomas.riedl@siemens.com> to track the number of jobs started in the
191 last second and artificially adjust GNU make's view of the system's
192 load average accordingly.
194 * New special variables available in this release:
195 - .INCLUDE_DIRS: Expands to a list of directories that make searches
196 for included makefiles.
197 - .FEATURES: Contains a list of special features available in this
199 - .DEFAULT_GOAL: Set the name of the default goal make will
200 use if no goals are provided on the command line.
201 - MAKE_RESTARTS: If set, then this is the number of times this
202 instance of make has been restarted (see "How Makefiles Are Remade"
204 - New automatic variable: $| (added in 3.80, actually): contains all
205 the order-only prerequisites defined for the target.
207 * New functions available in this release:
208 - $(lastword ...) returns the last word in the list. This gives
209 identical results as $(word $(words ...) ...), but is much faster.
210 - $(abspath ...) returns the absolute path (all "." and ".."
211 directories resolved, and any duplicate "/" characters removed) for
213 - $(realpath ...) returns the canonical pathname for each path
214 provided. The canonical pathname is the absolute pathname, with
215 all symbolic links resolved as well.
216 - $(info ...) prints its arguments to stdout. No makefile name or
217 line number info, etc. is printed.
218 - $(flavor ...) returns the flavor of a variable.
219 - $(or ...) provides a short-circuiting OR conditional: each argument
220 is expanded. The first true (non-empty) argument is returned; no
221 further arguments are expanded. Expands to empty if there are no
223 - $(and ...) provides a short-circuiting AND conditional: each
224 argument is expanded. The first false (empty) argument is
225 returned; no further arguments are expanded. Expands to the last
226 argument if all arguments are true.
228 * Changes made for POSIX compatibility:
229 - Only touch targets (under -t) if they have a recipe.
230 - Setting the SHELL make variable does NOT change the value of the
231 SHELL environment variable given to programs invoked by make. As
232 an enhancement to POSIX, if you export the make variable SHELL then
233 it will be set in the environment, just as before.
235 * On MS Windows systems, explicitly setting SHELL to a pathname ending
236 in "cmd" or "cmd.exe" (case-insensitive) will force GNU make to use
237 the DOS command interpreter in batch mode even if a UNIX-like shell
238 could be found on the system.
240 * On VMS there is now support for case-sensitive filesystems such as ODS5.
241 See the readme.vms file for information.
243 * Parallel builds (-jN) no longer require a working Bourne shell on
244 Windows platforms. They work even with the stock Windows shells, such
245 as cmd.exe and command.com.
247 * Updated to autoconf 2.59, automake 1.9.5, and gettext 0.14.1. Users
248 should not be impacted.
250 * New translations for Swedish, Chinese (simplified), Ukrainian,
251 Belarusian, Finnish, Kinyarwandan, and Irish. Many updated
254 A complete list of bugs fixed in this version is available here:
256 http://savannah.gnu.org/bugs/index.php?group=make&report_id=111&fix_release_id=103
261 * A new feature exists: order-only prerequisites. These prerequisites
262 affect the order in which targets are built, but they do not impact
263 the rebuild/no-rebuild decision of their dependents. That is to say,
264 they allow you to require target B be built before target A, without
265 requiring that target A will always be rebuilt if target B is updated.
266 Patch for this feature provided by Greg McGary <greg@mcgary.org>.
268 * For compatibility with SysV make, GNU make now supports the peculiar
269 syntax $$@, $$(@D), and $$(@F) in the prerequisites list of a rule.
270 This syntax is only valid within explicit and static pattern rules: it
271 cannot be used in implicit (suffix or pattern) rules. Edouard G. Parmelan
272 <egp@free.fr> provided a patch implementing this feature; however, I
273 decided to implement it in a different way.
275 * The argument to the "ifdef" conditional is now expanded before it's
276 tested, so it can be a constructed variable name.
278 Similarly, the arguments to "export" (when not used in a variable
279 definition context) and "unexport" are also now expanded.
281 * A new function is defined: $(value ...). The argument to this
282 function is the _name_ of a variable. The result of the function is
283 the value of the variable, without having been expanded.
285 * A new function is defined: $(eval ...). The arguments to this
286 function should expand to makefile commands, which will then be
287 evaluated as if they had appeared in the makefile. In combination
288 with define/endef multiline variable definitions this is an extremely
289 powerful capability. The $(value ...) function is also sometimes
292 * A new built-in variable is defined, $(MAKEFILE_LIST). It contains a
293 list of each makefile GNU make has read, or started to read, in the
294 order in which they were encountered. So, the last filename in the
295 list when a makefile is just being read (before any includes) is the
296 name of the current makefile.
298 * A new built-in variable is defined: $(.VARIABLES). When it is
299 expanded it returns a complete list of variable names defined by all
300 makefiles at that moment.
302 * A new command line option is defined, -B or --always-make. If
303 specified GNU make will consider all targets out-of-date even if they
304 would otherwise not be.
306 * The arguments to $(call ...) functions were being stored in $1, $2,
307 etc. as recursive variables, even though they are fully expanded
308 before assignment. This means that escaped dollar signs ($$ etc.)
309 were not behaving properly. Now the arguments are stored as simple
310 variables. This may mean that if you added extra escaping to your
311 $(call ...) function arguments you will need to undo it now.
313 * The variable invoked by $(call ...) can now be recursive: unlike other
314 variables it can reference itself and this will not produce an error
315 when it is used as the first argument to $(call ...) (but only then).
317 * New pseudo-target .LOW_RESOLUTION_TIME, superseding the configure
318 option --disable-nsec-timestamps. You might need this if your build
319 process depends on tools like "cp -p" preserving time stamps, since
320 "cp -p" (right now) doesn't preserve the subsecond portion of a time
323 * Updated translations for French, Galician, German, Japanese, Korean,
324 and Russian. New translations for Croatian, Danish, Hebrew, and
327 * Updated internationalization support to Gettext 0.11.5.
328 GNU make now uses Gettext's "external" feature, and does not include
329 any internationalization code itself. Configure will search your
330 system for an existing implementation of GNU Gettext (only GNU Gettext
331 is acceptable) and use it if it exists. If not, NLS will be disabled.
332 See ABOUT-NLS for more information.
334 * Updated to autoconf 2.54 and automake 1.7. Users should not be impacted.
336 A complete list of bugs fixed in this version is available here:
338 http://savannah.gnu.org/bugs/index.php?group=make&report_id=111&fix_release_id=102
343 * .SECONDARY with no prerequisites now prevents any target from being
344 removed because make thinks it's an intermediate file, not just those
345 listed in the makefile.
347 * New configure option --disable-nsec-timestamps, but this was
348 superseded in later versions by the .LOW_RESOLUTION_TIME pseudo-target.
352 * GNU make optionally supports internationalization and locales via the
353 GNU gettext (or local gettext if suitable) package. See the ABOUT-NLS
354 file for more information on configuring GNU make for NLS.
356 * Previously, GNU make quoted variables such as MAKEFLAGS and
357 MAKEOVERRIDES for proper parsing by the shell. This allowed them to
358 be used within make build scripts. However, using them there is not
359 proper behavior: they are meant to be passed to subshells via the
360 environment. Unfortunately the values were not quoted properly to be
361 passed through the environment. This meant that make didn't properly
362 pass some types of command line values to submakes.
364 With this version we change that behavior: now these variables are
365 quoted properly for passing through the environment, which is the
366 correct way to do it. If you previously used these variables
367 explicitly within a make rule you may need to re-examine your use for
368 correctness given this change.
370 * A new pseudo-target .NOTPARALLEL is available. If defined, the
371 current makefile is run serially regardless of the value of -j.
372 However, submakes are still eligible for parallel execution.
374 * The --debug option has changed: it now allows optional flags
375 controlling the amount and type of debugging output. By default only
376 a minimal amount information is generated, displaying the names of
377 "normal" targets (not makefiles) that were deemed out of date and in
378 need of being rebuilt.
380 Note that the -d option behaves as before: it takes no arguments and
381 all debugging information is generated.
383 * The `-p' (print database) output now includes filename and linenumber
384 information for variable definitions, to aid debugging.
386 * The wordlist function no longer reverses its arguments if the "start"
387 value is greater than the "end" value. If that's true, nothing is
390 * Hartmut Becker provided many updates for the VMS port of GNU make.
391 See the readme.vms file for more details.
395 * Two new functions, $(error ...) and $(warning ...) are available. The
396 former will cause make to fail and exit immediately upon expansion of
397 the function, with the text provided as the error message. The latter
398 causes the text provided to be printed as a warning message, but make
401 * A new function $(call ...) is available. This allows users to create
402 their own parameterized macros and invoke them later. Original
403 implementation of this function was provided by Han-Wen Nienhuys
406 * A new function $(if ...) is available. It provides if-then-else
407 capabilities in a builtin function. Original implementation of this
408 function was provided by Han-Wen Nienhuys <hanwen@cs.uu.nl>.
410 * Make defines a new variable, .LIBPATTERNS. This variable controls how
411 library dependency expansion (dependencies like ``-lfoo'') is performed.
413 * Make accepts CRLF sequences as well as traditional LF, for
414 compatibility with makefiles created on other operating systems.
416 * Make accepts a new option: -R, or --no-builtin-variables. This option
417 disables the definition of the rule-specific builtin variables (CC,
418 LD, AR, etc.). Specifying this option forces -r (--no-builtin-rules)
421 * A "job server" feature, suggested by Howard Chu <hyc@highlandsun.com>.
423 On systems that support POSIX pipe(2) semantics, GNU make can now pass
424 -jN options to submakes rather than forcing them all to use -j1. The
425 top make and all its sub-make processes use a pipe to communicate with
426 each other to ensure that no more than N jobs are started across all
427 makes. To get the old behavior of -j back, you can configure make
428 with the --disable-job-server option.
430 * The confusing term "dependency" has been replaced by the more accurate
431 and standard term "prerequisite", both in the manual and in all GNU make
434 * GNU make supports the "big archive" library format introduced in AIX 4.3.
436 * GNU make supports large files on AIX, HP-UX, and IRIX. These changes
437 were provided by Paul Eggert <eggert@twinsun.com>. (Large file
438 support for Solaris and Linux was introduced in 3.77, but the
439 configuration had issues: these have also been resolved).
441 * The Windows 95/98/NT (W32) version of GNU make now has native support
442 for the Cygnus Cygwin release B20.1 shell (bash).
444 * The GNU make regression test suite, long available separately "under
445 the table", has been integrated into the release. You can invoke it
446 by running "make check" in the distribution. Note that it requires
447 Perl (either Perl 4 or Perl 5) to run.
451 * Implement BSD make's "?=" variable assignment operator. The variable
452 is assigned the specified value only if that variable is not already
455 * Make defines a new variable, "CURDIR", to contain the current working
456 directory (after the -C option, if any, has been processed).
457 Modifying this variable has no effect on the operation of make.
459 * Make defines a new default RCS rule, for new-style master file
460 storage: ``% :: RCS/%'' (note no ``,v'' suffix).
462 Make defines new default rules for DOS-style C++ file naming
463 conventions, with ``.cpp'' suffixes. All the same rules as for
464 ``.cc'' and ``.C'' suffixes are provided, along with LINK.cpp and
465 COMPILE.cpp macros (which default to the same value as LINK.cc and
466 COMPILE.cc). Note CPPFLAGS is still C preprocessor flags! You should
467 use CXXFLAGS to change C++ compiler flags.
469 * A new feature, "target-specific variable values", has been added.
470 This is a large change so please see the appropriate sections of the
471 manual for full details. Briefly, syntax like this:
473 TARGET: VARIABLE = VALUE
475 defines VARIABLE as VALUE within the context of TARGET. This is
476 similar to SunOS make's "TARGET := VARIABLE = VALUE" feature. Note
477 that the assignment may be of any type, not just recursive, and that
478 the override keyword is available.
480 COMPATIBILITY: This new syntax means that if you have any rules where
481 the first or second dependency has an equal sign (=) in its name,
482 you'll have to escape them with a backslash: "foo : bar\=baz".
483 Further, if you have any dependencies which already contain "\=",
484 you'll have to escape both of them: "foo : bar\\\=baz".
486 * A new appendix listing the most common error and warning messages
487 generated by GNU make, with some explanation, has been added to the
488 GNU make User's Manual.
490 * Updates to the GNU make Customs library support (see README.customs).
492 * Updates to the Windows 95/NT port from Rob Tulloh (see README.W32),
493 and to the DOS port from Eli Zaretski (see README.DOS).
497 * Small (but serious) bug fix. Quick rollout to get into the GNU source CD.
501 * GNU make now uses automake to control Makefile.in generation. This
502 should make it more consistent with the GNU standards.
504 * VPATH functionality has been changed to incorporate the VPATH+ patch,
505 previously maintained by Paul Smith <psmith@baynetworks.com>. See the
508 * Make defines a new variable, `MAKECMDGOALS', to contain the goals that
509 were specified on the command line, if any. Modifying this variable
510 has no effect on the operation of make.
512 * A new function, `$(wordlist S,E,TEXT)', is available: it returns a
513 list of words from number S to number E (inclusive) of TEXT.
515 * Instead of an error, detection of future modification times gives a
516 warning and continues. The warning is repeated just before GNU make
517 exits, so it is less likely to be lost.
519 * Fix the $(basename) and $(suffix) functions so they only operate on
520 the last filename, not the entire string:
522 Command Old Result New Result
523 ------- ---------- ----------
525 $(basename a.b/c) a a.b/c
527 $(suffix a.b/c) b/c <empty>
529 * The $(strip) function now removes newlines as well as TABs and spaces.
531 * The $(shell) function now changes CRLF (\r\n) pairs to a space as well
534 * Updates to the Windows 95/NT port from Rob Tulloh (see README.W32).
536 * Eli Zaretskii has updated the port to 32-bit protected mode on MSDOS
537 and MS-Windows, building with the DJGPP v2 port of GNU C/C++ compiler
538 and utilities. See README.DOS for details, and direct all questions
539 concerning this port to Eli Zaretskii <eliz@is.elta.co.il> or DJ
540 Delorie <dj@delorie.com>.
542 * John W. Eaton has updated the VMS port to support libraries and VPATH.
546 * The directory messages printed by `-w' and implicitly in sub-makes,
547 are now omitted if Make runs no commands and has no other messages to print.
549 * Make now detects files that for whatever reason have modification times
550 in the future and gives an error. Files with such impossible timestamps
551 can result from unsynchronized clocks, or archived distributions
552 containing bogus timestamps; they confuse Make's dependency engine
555 * The new directive `sinclude' is now recognized as another name for
556 `-include', for compatibility with some other Makes.
558 * Aaron Digulla has contributed a port to AmigaDOS. See README.Amiga for
559 details, and direct all Amiga-related questions to <digulla@fh-konstanz.de>.
561 * Rob Tulloh of Tivoli Systems has contributed a port to Windows NT or 95.
562 See README.W32 for details, and direct all Windows-related questions to
563 <rob_tulloh@tivoli.com>.
567 * Converted to use Autoconf version 2, so `configure' has some new options.
568 See INSTALL for details.
570 * You can now send a SIGUSR1 signal to Make to toggle printing of debugging
571 output enabled by -d, at any time during the run.
575 * DJ Delorie has ported Make to MS-DOS using the GO32 extender.
576 He is maintaining the DOS port, not the GNU Make maintainer;
577 please direct bugs and questions for DOS to <djgpp@sun.soe.clarkson.edu>.
578 MS-DOS binaries are available for FTP from ftp.simtel.net in
579 /pub/simtelnet/gnu/djgpp/.
581 * The `MAKEFLAGS' variable (in the environment or in a makefile) can now
582 contain variable definitions itself; these are treated just like
583 command line variable definitions. Make will automatically insert any
584 variable definitions from the environment value of `MAKEFLAGS' or from
585 the command line, into the `MAKEFLAGS' value exported to children. The
586 `MAKEOVERRIDES' variable previously included in the value of `$(MAKE)'
587 for sub-makes is now included in `MAKEFLAGS' instead. As before, you can
588 reset `MAKEOVERRIDES' in your makefile to avoid putting all the variables
589 in the environment when its size is limited.
591 * If `.DELETE_ON_ERROR' appears as a target, Make will delete the target of
592 a rule if it has changed when its recipe exits with a nonzero status,
593 just as when the recipe gets a signal.
595 * The automatic variable `$+' is new. It lists all the dependencies like
596 `$^', but preserves duplicates listed in the makefile. This is useful
597 for linking rules, where library files sometimes need to be listed twice
600 * You can now specify the `.IGNORE' and `.SILENT' special targets with
601 dependencies to limit their effects to those files. If a file appears as
602 a dependency of `.IGNORE', then errors will be ignored while running the
603 recipe to update that file. Likewise if a file appears as a dependency
604 of `.SILENT', then the recipe to update that file will not be printed
605 before it is run. (This change was made to conform to POSIX.2.)
609 * The automatic variables `$(@D)', `$(%D)', `$(*D)', `$(<D)', `$(?D)', and
610 `$(^D)' now omit the trailing slash from the directory name. (This change
611 was made to comply with POSIX.2.)
613 * The source distribution now includes the Info files for the Make manual.
614 There is no longer a separate distribution containing Info and DVI files.
616 * You can now set the variables `binprefix' and/or `manprefix' in
617 Makefile.in (or on the command line when installing) to install GNU make
618 under a name other than `make' (i.e., ``make binprefix=g install''
619 installs GNU make as `gmake').
621 * The built-in Texinfo rules use the new variables `TEXI2DVI_FLAGS' for
622 flags to the `texi2dvi' script, and `MAKEINFO_FLAGS' for flags to the
625 * The exit status of Make when it runs into errors is now 2 instead of 1.
626 The exit status is 1 only when using -q and some target is not up to date.
627 (This change was made to comply with POSIX.2.)
631 * It is no longer a fatal error to have a NUL character in a makefile.
632 You should never put a NUL in a makefile because it can have strange
633 results, but otherwise empty lines full of NULs (such as produced by
634 the `xmkmf' program) will always work fine.
636 * The error messages for nonexistent included makefiles now refer to the
637 makefile name and line number where the `include' appeared, so Emacs's
638 C-x ` command takes you there (in case it's a typo you need to fix).
642 * Implicit rule search for archive member references is now done in the
643 opposite order from previous versions: the whole target name `LIB(MEM)'
644 first, and just the member name and parentheses `(MEM)' second.
646 * Make now gives an error for an unterminated variable or function reference.
647 For example, `$(foo' with no matching `)' or `${bar' with no matching `}'.
649 * The new default variable `MAKE_VERSION' gives the version number of
650 Make, and a string describing the remote job support compiled in (if any).
651 Thus the value (in this release) is something like `3.69' or `3.69-Customs'.
653 * Commands in an invocation of the `shell' function are no longer run
654 with a modified environment like recipes are. As in versions before
655 3.68, they now run with the environment that `make' started with. We
656 have reversed the change made in version 3.68 because it turned out to
657 cause a paradoxical situation in cases like:
659 export variable = $(shell echo value)
661 When Make attempted to put this variable in the environment for a
662 recipe, it would try expand the value by running the shell command
663 `echo value'. In version 3.68, because it constructed an environment
664 for that shell command in the same way, Make would begin to go into an
665 infinite loop and then get a fatal error when it detected the loop.
667 * The recipe given for `.DEFAULT' is now used for phony targets with no
672 * You can list several archive member names inside parenthesis:
673 `lib(mem1 mem2 mem3)' is equivalent to `lib(mem1) lib(mem2) lib(mem3)'.
675 * You can use wildcards inside archive member references. For example,
676 `lib(*.o)' expands to all existing members of `lib' whose names end in
677 `.o' (e.g. `lib(a.o) lib(b.o)'); `*.a(*.o)' expands to all such members
678 of all existing files whose names end in `.a' (e.g. `foo.a(a.o)
679 foo.a(b.o) bar.a(c.o) bar.a(d.o)'.
681 * A suffix rule `.X.a' now produces two pattern rules:
682 (%.o): %.X # Previous versions produced only this.
683 %.a: %.X # Now produces this as well, just like other suffixes.
685 * The new flag `--warn-undefined-variables' says to issue a warning message
686 whenever Make expands a reference to an undefined variable.
688 * The new `-include' directive is just like `include' except that there is
689 no error (not even a warning) for a nonexistent makefile.
691 * Commands in an invocation of the `shell' function are now run with a
692 modified environment like recipes are, so you can use `export' et al
693 to set up variables for them. They used to run with the environment
694 that `make' started with.
698 * `make --version' (or `make -v') now exits immediately after printing
703 * Make now supports long-named members in `ar' archive files.
707 * Make now supports the `+=' syntax for a variable definition which appends
708 to the variable's previous value. See the section `Appending More Text
709 to Variables' in the manual for full details.
711 * The new option `--no-print-directory' inhibits the `-w' or
712 `--print-directory' feature. Make turns on `--print-directory'
713 automatically if you use `-C' or `--directory', and in sub-makes; some
714 users have found this behavior undesirable.
716 * The built-in implicit rules now support the alternative extension
717 `.txinfo' for Texinfo files, just like `.texinfo' and `.texi'.
721 * Make now uses a standard GNU `configure' script. See the new file
722 INSTALL for the new (and much simpler) installation procedure.
724 * There is now a shell script to build Make the first time, if you have no
725 other `make' program. `build.sh' is created by `configure'; see README.
727 * GNU Make now completely conforms to the POSIX.2 specification for `make'.
729 * Elements of the `$^' and `$?' automatic variables that are archive
730 member references now list only the member name, as in Unix and POSIX.2.
732 * You should no longer ever need to specify the `-w' switch, which prints
733 the current directory before and after Make runs. The `-C' switch to
734 change directory, and recursive use of Make, now set `-w' automatically.
736 * Multiple double-colon rules for the same target will no longer have their
737 recipes run simultaneously under -j, as this could result in the two
738 recipes trying to change the file at the same time and interfering with
741 * The `SHELL' variable is now never taken from the environment.
742 Each makefile that wants a shell other than the default (/bin/sh) must
743 set SHELL itself. SHELL is always exported to child processes.
744 This change was made for compatibility with POSIX.2.
746 * Make now accepts long options. There is now an informative usage message
747 that tells you what all the options are and what they do. Try `make --help'.
749 * There are two new directives: `export' and `unexport'. All variables are
750 no longer automatically put into the environments of the recipe lines that
751 Make runs. Instead, only variables specified on the command line or in
752 the environment are exported by default. To export others, use:
754 or you can define variables with:
755 export VARIABLE = VALUE
757 export VARIABLE := VALUE
761 .EXPORT_ALL_VARIABLES:
762 to get the old behavior. See the node `Variables/Recursion' in the manual
763 for a full description.
765 * The recipe from the `.DEFAULT' special target is only applied to
766 targets which have no rules at all, not all targets with no recipe.
767 This change was made for compatibility with Unix make.
769 * All fatal error messages now contain `***', so they are easy to find in
772 * Dependency file names like `-lNAME' are now replaced with the actual file
773 name found, as with files found by normal directory search (VPATH).
774 The library file `libNAME.a' may now be found in the current directory,
775 which is checked before VPATH; the standard set of directories (/lib,
776 /usr/lib, /usr/local/lib) is now checked last.
777 See the node `Libraries/Search' in the manual for full details.
779 * A single `include' directive can now specify more than one makefile to
782 You can also use shell file name patterns in an `include' directive:
785 * The default directories to search for included makefiles, and for
786 libraries specified with `-lNAME', are now set by configuration.
788 * You can now use blanks as well as colons to separate the directories in a
789 search path for the `vpath' directive or the `VPATH' variable.
791 * You can now use variables and functions in the left hand side of a
792 variable assignment, as in "$(foo)bar = value".
794 * The `MAKE' variable is always defined as `$(MAKE_COMMAND) $(MAKEOVERRIDES)'.
795 The `MAKE_COMMAND' variable is now defined to the name with which make
798 * The built-in rules for C++ compilation now use the variables `$(CXX)' and
799 `$(CXXFLAGS)' instead of `$(C++)' and `$(C++FLAGS)'. The old names had
800 problems with shells that cannot have `+' in environment variable names.
802 * The value of a recursively expanded variable is now expanded when putting
803 it into the environment for child processes. This change was made for
804 compatibility with Unix make.
806 * A rule with no targets before the `:' is now accepted and ignored.
807 This change was made for compatibility with SunOS 4 make.
808 We do not recommend that you write your makefiles to take advantage of this.
810 * The `-I' switch can now be used in MAKEFLAGS, and are put there
811 automatically just like other switches.
815 * Built-in rules for C++ source files with the `.C' suffix.
816 We still recommend that you use `.cc' instead.
818 * If a recipe is given too many times for a single target, the last one
819 given is used, and a warning message is printed.
821 * Error messages about makefiles are in standard GNU error format,
822 so C-x ` in Emacs works on them.
824 * Dependencies of pattern rules which contain no % need not actually exist
825 if they can be created (just like dependencies which do have a %).
829 * A message is always printed when Make decides there is nothing to be done.
830 It used to be that no message was printed for top-level phony targets
831 (because "`phony' is up to date" isn't quite right). Now a different
832 message "Nothing to be done for `phony'" is printed in that case.
834 * Archives on AIX now supposedly work.
836 * When the recipes specified for .DEFAULT are used to update a target,
837 the $< automatic variable is given the same value as $@ for that target.
838 This is how Unix make behaves, and this behavior is mandated by POSIX.2.
842 * The -n, -q, and -t options are not put in the `MAKEFLAGS' and `MFLAG'
843 variables while remaking makefiles, so recursive makes done while remaking
844 makefiles will behave properly.
846 * If the special target `.NOEXPORT' is specified in a makefile,
847 only variables that came from the environment and variables
848 defined on the command line are exported.
852 * Suffix rules may have dependencies (which are ignored).
856 * Dependencies of the form `-lLIB' are searched for as /usr/local/lib/libLIB.a
857 as well as libLIB.a in /usr/lib, /lib, the current directory, and VPATH.
861 * There is now a Unix man page for GNU Make. It is certainly not a
862 replacement for the Texinfo manual, but it documents the basic
863 functionality and the switches. For full documentation, you should
864 still read the Texinfo manual. Thanks to Dennis Morse of Stanford
865 University for contributing the initial version of this.
867 * Variables which are defined by default (e.g., `CC') will no longer be
868 put into the environment for child processes. (If these variables are
869 reset by the environment, makefiles, or the command line, they will
870 still go into the environment.)
872 * Makefiles which have recipes but no dependencies (and thus are always
873 considered out of date and in need of remaking), will not be remade (if they
874 were being remade only because they were makefiles). This means that GNU
875 Make will no longer go into an infinite loop when fed the makefiles that
876 `imake' (necessary to build X Windows) produces.
878 * There is no longer a warning for using the `vpath' directive with an explicit
879 pathname (instead of a `%' pattern).
883 * When removing intermediate files, only one `rm' command line is printed,
884 listing all file names.
886 * There are now automatic variables `$(^D)', `$(^F)', `$(?D)', and `$(?F)'.
887 These are the directory-only and file-only versions of `$^' and `$?'.
889 * Library dependencies given as `-lNAME' will use "libNAME.a" in the current
890 directory if it exists.
892 * The automatic variable `$($/)' is no longer defined.
894 * Leading `+' characters on a recipe line make that line be executed even
895 under -n, -t, or -q (as if the line contained `$(MAKE)').
897 * For recipe lines containing `$(MAKE)', `${MAKE}', or leading `+' characters,
898 only those lines are executed, not the entire recipe.
899 (This is how Unix make behaves for lines containing `$(MAKE)' or `${MAKE}'.)
903 * Filenames in rules will now have ~ and ~USER expanded.
905 * The `-p' output has been changed so it can be used as a makefile.
906 (All information that isn't specified by makefiles is prefaced with comment
911 * The % character can be quoted with backslash in implicit pattern rules,
912 static pattern rules, `vpath' directives, and `patsubst', `filter', and
913 `filter-out' functions. A warning is issued if a `vpath' directive's
914 pattern contains no %.
916 * The `wildcard' variable expansion function now expands ~ and ~USER.
918 * Messages indicating failed recipe lines now contain the target name:
919 make: *** [target] Error 1
921 * The `-p' output format has been changed somewhat to look more like
922 makefile rules and to give all information that Make has about files.
928 * The `-l' switch with no argument removes any previous load-average limit.
930 * When the `-w' switch is in effect, and Make has updated makefiles,
931 it will write a `Leaving directory' message before re-executing itself.
932 This makes the `directory change tracking' changes to Emacs's compilation
933 commands work properly.
937 * The automatic variable `$*' is now defined for explicit rules,
938 as it is in Unix make.
942 * The `-j' switch is now put in the MAKEFLAGS and MFLAGS variables when
943 specified without an argument (indicating infinite jobs).
944 The `-l' switch is not always put in the MAKEFLAGS and MFLAGS variables.
946 * Make no longer checks hashed directories after running recipes.
947 The behavior implemented in 3.41 caused too much slowdown.
951 * A dependency is NOT considered newer than its dependent if
952 they have the same modification time. The behavior implemented
953 in 3.43 conflicts with RCS.
957 * Dependency loops are no longer fatal errors.
959 * A dependency is considered newer than its dependent if
960 they have the same modification time.
964 * The variables F77 and F77FLAGS are now set by default to $(FC) and
965 $(FFLAGS). Makefiles designed for System V make may use these variables in
966 explicit rules and expect them to be set. Unfortunately, there is no way to
967 make setting these affect the Fortran implicit rules unless FC and FFLAGS
968 are not used (and these are used by BSD make).
972 * Make now checks to see if its hashed directories are changed by recipes.
973 Other makes that hash directories (Sun, 4.3 BSD) don't do this.
977 * The `shell' function no longer captures standard error output.
981 * A file beginning with a dot can be the default target if it also contains
982 a slash (e.g., `../bin/foo'). (Unix make allows this as well.)
986 * Archive member names are truncated to 15 characters.
988 * Yet more USG stuff.
990 * Minimal support for Microport System V (a 16-bit machine and a
991 brain-damaged compiler). This has even lower priority than other USG
992 support, so if it gets beyond trivial, I will take it out completely.
994 * Revamped default implicit rules (not much visible change).
996 * The -d and -p options can come from the environment.
1000 * Improved support for USG and HPUX (hopefully).
1002 * A variable reference like `$(foo:a=b)', if `a' contains a `%', is
1003 equivalent to `$(patsubst a,b,$(foo))'.
1005 * Defining .DEFAULT with no deps or recipe clears its recipe.
1007 * New default implicit rules for .S (cpp, then as), and .sh (copy and
1008 make executable). All default implicit rules that use cpp (even
1009 indirectly), use $(CPPFLAGS).
1013 * Giving the -j option with no arguments gives you infinite jobs.
1017 * New option: "-l LOAD" says not to start any new jobs while others are
1018 running if the load average is not below LOAD (a floating-point number).
1020 * There is support in place for implementations of remote command execution
1021 in Make. See the file remote.c.
1025 * No more than 10 directories will be kept open at once.
1026 (This number can be changed by redefining MAX_OPEN_DIRECTORIES in dir.c.)
1030 * Archive files will have their modification times recorded before doing
1031 anything that might change their modification times by updating an archive
1036 * The `MAKELEVEL' variable is defined for use by makefiles.
1040 * The recursion level indications in error messages are much shorter than
1041 they were in version 3.14.
1045 * Leading spaces before directives are ignored (as documented).
1047 * Included makefiles can determine the default goal target.
1048 (System V Make does it this way, so we are being compatible).
1052 * Variables that are defaults built into Make will not be put in the
1053 environment for children. This just saves some environment space and,
1054 except under -e, will be transparent to sub-makes.
1056 * Error messages from sub-makes will indicate the level of recursion.
1058 * Hopefully some speed-up for large directories due to a change in the
1059 directory hashing scheme.
1061 * One child will always get a standard input that is usable.
1063 * Default makefiles that don't exist will be remade and read in.
1067 * Count parentheses inside expansion function calls so you can
1068 have nested calls: `$(sort $(foreach x,a b,$(x)))'.
1072 * Several bug fixes, including USG and Sun386i support.
1074 * `shell' function to expand shell commands a la `
1076 * If the `-d' flag is given, version information will be printed.
1078 * The `-c' option has been renamed to `-C' for compatibility with tar.
1080 * The `-p' option no longer inhibits other normal operation.
1082 * Makefiles will be updated and re-read if necessary.
1084 * Can now run several recipes at once (parallelism), -j option.
1086 * Error messages will contain the level of Make recursion, if any.
1088 * The `MAKEFLAGS' and `MFLAGS' variables will be scanned for options after
1091 * A double-colon rule with no dependencies will always have its recipe run.
1092 (This is how both the BSD and System V versions of Make do it.)
1096 (Changes from versions 1 through 3.05 were never recorded. Sorry.)
1098 -------------------------------------------------------------------------------
1099 Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
1100 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
1101 2010 Free Software Foundation, Inc. This file is part of GNU Make.
1103 GNU Make is free software; you can redistribute it and/or modify it under the
1104 terms of the GNU General Public License as published by the Free Software
1105 Foundation; either version 3 of the License, or (at your option) any later
1108 GNU Make is distributed in the hope that it will be useful, but WITHOUT ANY
1109 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
1110 A PARTICULAR PURPOSE. See the GNU General Public License for more details.
1112 You should have received a copy of the GNU General Public License along with
1113 this program. If not, see <http://www.gnu.org/licenses/>.