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=101&set=custom
18 * WARNING: Backward-incompatibility!
19 This version of make adheres to the POSIX backslash/newline handling,
20 introducing the following differences:
21 * Each backslash/newline in a variable value is replaced with a space;
22 multiple consecutive backslash/newlines do not condense into one space.
23 * In recipes, a recipe prefix following a backslash-newlines is removed.
25 * New command line option: --trace enables tracing of targets. When enabled
26 the recipe to be invoked is printed even if it would otherwise be suppressed
27 by .SILENT or a "@" prefix character. Also before each recipe is run the
28 makefile name and linenumber where it was defined are shown as well as the
29 prerequisites that caused the target to be considered out of date.
31 * On failure, the makefile name and linenumber of the recipe that failed are
34 * A .RECIPEPREFIX setting is remembered per-recipe and variables expanded
35 in that recipe also use that recipe prefix setting.
37 * In -p output, .RECIPEPREFIX settings are shown and all target-specific
38 variables are output as if in a makefile, instead of as comments.
43 A complete list of bugs fixed in this version is available here:
45 http://sv.gnu.org/bugs/index.php?group=make&report_id=111&fix_release_id=104&set=custom
47 * Compiling GNU make now requires a conforming ISO C 1989 compiler and
48 standard runtime library.
50 * WARNING: Backward-incompatibility!
51 The POSIX standard for make was changed in the 2008 version in a
52 fundamentally incompatible way: make is required to invoke the shell as if
53 the '-e' flag were provided. Because this would break many makefiles that
54 have been written to conform to the original text of the standard, the
55 default behavior of GNU make remains to invoke the shell with simply '-c'.
56 However, any makefile specifying the .POSIX special target will follow the
57 new POSIX standard and pass '-e' to the shell. See also .SHELLFLAGS
60 * WARNING: Backward-incompatibility!
61 The '$?' variable now contains all prerequisites that caused the target to
62 be considered out of date, even if they do not exist (previously only
63 existing targets were provided in $?).
65 * WARNING: Backward-incompatibility!
66 Wildcards were not documented as returning sorted values, but the results
67 have been sorted up until this release.. If your makefiles require sorted
68 results from wildcard expansions, use the $(sort ...) function to request
71 * WARNING: Backward-incompatibility!
72 In previous versions of make it was acceptable to list one or more explicit
73 targets followed by one or more pattern targets in the same rule and it
74 worked "as expected". However, this was not documented as acceptable and if
75 you listed any explicit targets AFTER the pattern targets, the entire rule
76 would be mis-parsed. This release removes this ability completely: make
77 will generate an error message if you mix explicit and pattern targets in
80 * WARNING: Backward-incompatibility!
81 As a result of parser enhancements, three backward-compatibility issues
82 exist: first, a prerequisite containing an "=" cannot be escaped with a
83 backslash any longer. You must create a variable containing an "=" and
84 use that variable in the prerequisite. Second, variable names can no
85 longer contain whitespace, unless you put the whitespace in a variable and
86 use the variable. Third, in previous versions of make it was sometimes
87 not flagged as an error for explicit and pattern targets to appear in the
88 same rule. Now this is always reported as an error.
90 * WARNING: Backward-incompatibility!
91 The pattern-specific variables and pattern rules are now applied in the
92 shortest stem first order instead of the definition order (variables
93 and rules with the same stem length are still applied in the definition
94 order). This produces the usually-desired behavior where more specific
95 patterns are preferred. To detect this feature search for 'shortest-stem'
96 in the .FEATURES special variable.
98 * WARNING: Backward-incompatibility!
99 The library search behavior has changed to be compatible with the standard
100 linker behavior. Prior to this version for prerequisites specified using
101 the -lfoo syntax make first searched for libfoo.so in the current
102 directory, vpath directories, and system directories. If that didn't yield
103 a match, make then searched for libfoo.a in these directories. Starting
104 with this version make searches first for libfoo.so and then for libfoo.a
105 in each of these directories in order.
107 * New command line option: --eval=STRING causes STRING to be evaluated as
108 makefile syntax (akin to using the $(eval ...) function). The evaluation
109 is performed after all default rules and variables are defined, but before
110 any makefiles are read.
112 * New special variable: .RECIPEPREFIX allows you to reset the recipe
113 introduction character from the default (TAB) to something else. The
114 first character of this variable value is the new recipe introduction
115 character. If the variable is set to the empty string, TAB is used again.
116 It can be set and reset at will; recipes will use the value active when
117 they were first parsed. To detect this feature check the value of
120 * New special variable: .SHELLFLAGS allows you to change the options passed
121 to the shell when it invokes recipes. By default the value will be "-c"
122 (or "-ec" if .POSIX is set).
124 * New special target: .ONESHELL instructs make to invoke a single instance
125 of the shell and provide it with the entire recipe, regardless of how many
126 lines it contains. As a special feature to allow more straightforward
127 conversion of makefiles to use .ONESHELL, any recipe line control
128 characters ('@', '+', or '-') will be removed from the second and
129 subsequent recipe lines. This happens _only_ if the SHELL value is deemed
130 to be a standard POSIX-style shell. If not, then no interior line control
131 characters are removed (as they may be part of the scripting language used
132 with the alternate SHELL).
134 * New variable modifier 'private': prefixing a variable assignment with the
135 modifier 'private' suppresses inheritance of that variable by
136 prerequisites. This is most useful for target- and pattern-specific
139 * New make directive: 'undefine' allows you to undefine a variable so that
140 it appears as if it was never set. Both $(flavor) and $(origin) functions
141 will return 'undefined' for such a variable. To detect this feature search
142 for 'undefine' in the .FEATURES special variable.
144 * The parser for variable assignments has been enhanced to allow multiple
145 modifiers ('export', 'override', 'private') on the same line as variables,
146 including define/endef variables, and in any order. Also, it is possible
147 to create variables and targets named as these modifiers.
149 * The 'define' make directive now allows a variable assignment operator
150 after the variable name, to allow for simple, conditional, or appending
151 multi-line variable assignment.
156 * GNU make is ported to OS/2.
158 * GNU make is ported to MinGW. The MinGW build is only supported by
159 the build_w32.bat batch file; see the file README.W32 for more
162 * WARNING: Future backward-incompatibility!
163 Up to and including this release, the '$?' variable does not contain
164 any prerequisite that does not exist, even though that prerequisite
165 might have caused the target to rebuild. Starting with the _next_
166 release of GNU make, '$?' will contain all prerequisites that caused
167 the target to be considered out of date. See this Savannah bug:
168 http://savannah.gnu.org/bugs/index.php?func=detailitem&item_id=16051
170 * WARNING: Backward-incompatibility!
171 GNU make now implements a generic "second expansion" feature on the
172 prerequisites of both explicit and implicit (pattern) rules. In order
173 to enable this feature, the special target '.SECONDEXPANSION' must be
174 defined before the first target which takes advantage of it. If this
175 feature is enabled then after all rules have been parsed the
176 prerequisites are expanded again, this time with all the automatic
177 variables in scope. This means that in addition to using standard
178 SysV $$@ in prerequisites lists, you can also use complex functions
179 such as $$(notdir $$@) etc. This behavior applies to implicit rules,
180 as well, where the second expansion occurs when the rule is matched.
181 However, this means that when '.SECONDEXPANSION' is enabled you must
182 double-quote any "$" in your filenames; instead of "foo: boo$$bar" you
183 now must write "foo: foo$$$$bar". Note that the SysV $$@ etc. feature,
184 which used to be available by default, is now ONLY available when the
185 .SECONDEXPANSION target is defined. If your makefiles take advantage
186 of this SysV feature you will need to update them.
188 * WARNING: Backward-incompatibility!
189 In order to comply with POSIX, the way in which GNU make processes
190 backslash-newline sequences in recipes has changed. If your makefiles
191 use backslash-newline sequences inside of single-quoted strings in
192 recipes you will be impacted by this change. See the GNU make manual
193 subsection "Splitting Recipe Lines" (node "Splitting Lines"), in
194 section "Recipe Syntax", chapter "Writing Recipe in Rules", for
197 * WARNING: Backward-incompatibility!
198 Some previous versions of GNU make had a bug where "#" in a function
199 invocation such as $(shell ...) was treated as a make comment. A
200 workaround was to escape these with backslashes. This bug has been
201 fixed: if your makefile uses "\#" in a function invocation the
202 backslash is now preserved, so you'll need to remove it.
204 * New command line option: -L (--check-symlink-times). On systems that
205 support symbolic links, if this option is given then GNU make will
206 use the most recent modification time of any symbolic links that are
207 used to resolve target files. The default behavior remains as it
208 always has: use the modification time of the actual target file only.
210 * The "else" conditional line can now be followed by any other valid
211 conditional on the same line: this does not increase the depth of the
212 conditional nesting, so only one "endif" is required to close the
215 * All pattern-specific variables that match a given target are now used
216 (previously only the first match was used).
218 * Target-specific variables can be marked as exportable using the
221 * In a recursive $(call ...) context, any extra arguments from the outer
222 call are now masked in the context of the inner call.
224 * Implemented a solution for the "thundering herd" problem with "-j -l".
225 This version of GNU make uses an algorithm suggested by Thomas Riedl
226 <thomas.riedl@siemens.com> to track the number of jobs started in the
227 last second and artificially adjust GNU make's view of the system's
228 load average accordingly.
230 * New special variables available in this release:
231 - .INCLUDE_DIRS: Expands to a list of directories that make searches
232 for included makefiles.
233 - .FEATURES: Contains a list of special features available in this
235 - .DEFAULT_GOAL: Set the name of the default goal make will
236 use if no goals are provided on the command line.
237 - MAKE_RESTARTS: If set, then this is the number of times this
238 instance of make has been restarted (see "How Makefiles Are Remade"
240 - New automatic variable: $| (added in 3.80, actually): contains all
241 the order-only prerequisites defined for the target.
243 * New functions available in this release:
244 - $(lastword ...) returns the last word in the list. This gives
245 identical results as $(word $(words ...) ...), but is much faster.
246 - $(abspath ...) returns the absolute path (all "." and ".."
247 directories resolved, and any duplicate "/" characters removed) for
249 - $(realpath ...) returns the canonical pathname for each path
250 provided. The canonical pathname is the absolute pathname, with
251 all symbolic links resolved as well.
252 - $(info ...) prints its arguments to stdout. No makefile name or
253 line number info, etc. is printed.
254 - $(flavor ...) returns the flavor of a variable.
255 - $(or ...) provides a short-circuiting OR conditional: each argument
256 is expanded. The first true (non-empty) argument is returned; no
257 further arguments are expanded. Expands to empty if there are no
259 - $(and ...) provides a short-circuiting AND conditional: each
260 argument is expanded. The first false (empty) argument is
261 returned; no further arguments are expanded. Expands to the last
262 argument if all arguments are true.
264 * Changes made for POSIX compatibility:
265 - Only touch targets (under -t) if they have a recipe.
266 - Setting the SHELL make variable does NOT change the value of the
267 SHELL environment variable given to programs invoked by make. As
268 an enhancement to POSIX, if you export the make variable SHELL then
269 it will be set in the environment, just as before.
271 * On MS Windows systems, explicitly setting SHELL to a pathname ending
272 in "cmd" or "cmd.exe" (case-insensitive) will force GNU make to use
273 the DOS command interpreter in batch mode even if a UNIX-like shell
274 could be found on the system.
276 * On VMS there is now support for case-sensitive filesystems such as ODS5.
277 See the readme.vms file for information.
279 * Parallel builds (-jN) no longer require a working Bourne shell on
280 Windows platforms. They work even with the stock Windows shells, such
281 as cmd.exe and command.com.
283 * Updated to autoconf 2.59, automake 1.9.5, and gettext 0.14.1. Users
284 should not be impacted.
286 * New translations for Swedish, Chinese (simplified), Ukrainian,
287 Belarusian, Finnish, Kinyarwandan, and Irish. Many updated
290 A complete list of bugs fixed in this version is available here:
292 http://savannah.gnu.org/bugs/index.php?group=make&report_id=111&fix_release_id=103
297 * A new feature exists: order-only prerequisites. These prerequisites
298 affect the order in which targets are built, but they do not impact
299 the rebuild/no-rebuild decision of their dependents. That is to say,
300 they allow you to require target B be built before target A, without
301 requiring that target A will always be rebuilt if target B is updated.
302 Patch for this feature provided by Greg McGary <greg@mcgary.org>.
304 * For compatibility with SysV make, GNU make now supports the peculiar
305 syntax $$@, $$(@D), and $$(@F) in the prerequisites list of a rule.
306 This syntax is only valid within explicit and static pattern rules: it
307 cannot be used in implicit (suffix or pattern) rules. Edouard G. Parmelan
308 <egp@free.fr> provided a patch implementing this feature; however, I
309 decided to implement it in a different way.
311 * The argument to the "ifdef" conditional is now expanded before it's
312 tested, so it can be a constructed variable name.
314 Similarly, the arguments to "export" (when not used in a variable
315 definition context) and "unexport" are also now expanded.
317 * A new function is defined: $(value ...). The argument to this
318 function is the _name_ of a variable. The result of the function is
319 the value of the variable, without having been expanded.
321 * A new function is defined: $(eval ...). The arguments to this
322 function should expand to makefile commands, which will then be
323 evaluated as if they had appeared in the makefile. In combination
324 with define/endef multiline variable definitions this is an extremely
325 powerful capability. The $(value ...) function is also sometimes
328 * A new built-in variable is defined, $(MAKEFILE_LIST). It contains a
329 list of each makefile GNU make has read, or started to read, in the
330 order in which they were encountered. So, the last filename in the
331 list when a makefile is just being read (before any includes) is the
332 name of the current makefile.
334 * A new built-in variable is defined: $(.VARIABLES). When it is
335 expanded it returns a complete list of variable names defined by all
336 makefiles at that moment.
338 * A new command line option is defined, -B or --always-make. If
339 specified GNU make will consider all targets out-of-date even if they
340 would otherwise not be.
342 * The arguments to $(call ...) functions were being stored in $1, $2,
343 etc. as recursive variables, even though they are fully expanded
344 before assignment. This means that escaped dollar signs ($$ etc.)
345 were not behaving properly. Now the arguments are stored as simple
346 variables. This may mean that if you added extra escaping to your
347 $(call ...) function arguments you will need to undo it now.
349 * The variable invoked by $(call ...) can now be recursive: unlike other
350 variables it can reference itself and this will not produce an error
351 when it is used as the first argument to $(call ...) (but only then).
353 * New pseudo-target .LOW_RESOLUTION_TIME, superseding the configure
354 option --disable-nsec-timestamps. You might need this if your build
355 process depends on tools like "cp -p" preserving time stamps, since
356 "cp -p" (right now) doesn't preserve the subsecond portion of a time
359 * Updated translations for French, Galician, German, Japanese, Korean,
360 and Russian. New translations for Croatian, Danish, Hebrew, and
363 * Updated internationalization support to Gettext 0.11.5.
364 GNU make now uses Gettext's "external" feature, and does not include
365 any internationalization code itself. Configure will search your
366 system for an existing implementation of GNU Gettext (only GNU Gettext
367 is acceptable) and use it if it exists. If not, NLS will be disabled.
368 See ABOUT-NLS for more information.
370 * Updated to autoconf 2.54 and automake 1.7. Users should not be impacted.
372 A complete list of bugs fixed in this version is available here:
374 http://savannah.gnu.org/bugs/index.php?group=make&report_id=111&fix_release_id=102
379 * .SECONDARY with no prerequisites now prevents any target from being
380 removed because make thinks it's an intermediate file, not just those
381 listed in the makefile.
383 * New configure option --disable-nsec-timestamps, but this was
384 superseded in later versions by the .LOW_RESOLUTION_TIME pseudo-target.
388 * GNU make optionally supports internationalization and locales via the
389 GNU gettext (or local gettext if suitable) package. See the ABOUT-NLS
390 file for more information on configuring GNU make for NLS.
392 * Previously, GNU make quoted variables such as MAKEFLAGS and
393 MAKEOVERRIDES for proper parsing by the shell. This allowed them to
394 be used within make build scripts. However, using them there is not
395 proper behavior: they are meant to be passed to subshells via the
396 environment. Unfortunately the values were not quoted properly to be
397 passed through the environment. This meant that make didn't properly
398 pass some types of command line values to submakes.
400 With this version we change that behavior: now these variables are
401 quoted properly for passing through the environment, which is the
402 correct way to do it. If you previously used these variables
403 explicitly within a make rule you may need to re-examine your use for
404 correctness given this change.
406 * A new pseudo-target .NOTPARALLEL is available. If defined, the
407 current makefile is run serially regardless of the value of -j.
408 However, submakes are still eligible for parallel execution.
410 * The --debug option has changed: it now allows optional flags
411 controlling the amount and type of debugging output. By default only
412 a minimal amount information is generated, displaying the names of
413 "normal" targets (not makefiles) that were deemed out of date and in
414 need of being rebuilt.
416 Note that the -d option behaves as before: it takes no arguments and
417 all debugging information is generated.
419 * The `-p' (print database) output now includes filename and linenumber
420 information for variable definitions, to aid debugging.
422 * The wordlist function no longer reverses its arguments if the "start"
423 value is greater than the "end" value. If that's true, nothing is
426 * Hartmut Becker provided many updates for the VMS port of GNU make.
427 See the readme.vms file for more details.
431 * Two new functions, $(error ...) and $(warning ...) are available. The
432 former will cause make to fail and exit immediately upon expansion of
433 the function, with the text provided as the error message. The latter
434 causes the text provided to be printed as a warning message, but make
437 * A new function $(call ...) is available. This allows users to create
438 their own parameterized macros and invoke them later. Original
439 implementation of this function was provided by Han-Wen Nienhuys
442 * A new function $(if ...) is available. It provides if-then-else
443 capabilities in a builtin function. Original implementation of this
444 function was provided by Han-Wen Nienhuys <hanwen@cs.uu.nl>.
446 * Make defines a new variable, .LIBPATTERNS. This variable controls how
447 library dependency expansion (dependencies like ``-lfoo'') is performed.
449 * Make accepts CRLF sequences as well as traditional LF, for
450 compatibility with makefiles created on other operating systems.
452 * Make accepts a new option: -R, or --no-builtin-variables. This option
453 disables the definition of the rule-specific builtin variables (CC,
454 LD, AR, etc.). Specifying this option forces -r (--no-builtin-rules)
457 * A "job server" feature, suggested by Howard Chu <hyc@highlandsun.com>.
459 On systems that support POSIX pipe(2) semantics, GNU make can now pass
460 -jN options to submakes rather than forcing them all to use -j1. The
461 top make and all its sub-make processes use a pipe to communicate with
462 each other to ensure that no more than N jobs are started across all
463 makes. To get the old behavior of -j back, you can configure make
464 with the --disable-job-server option.
466 * The confusing term "dependency" has been replaced by the more accurate
467 and standard term "prerequisite", both in the manual and in all GNU make
470 * GNU make supports the "big archive" library format introduced in AIX 4.3.
472 * GNU make supports large files on AIX, HP-UX, and IRIX. These changes
473 were provided by Paul Eggert <eggert@twinsun.com>. (Large file
474 support for Solaris and Linux was introduced in 3.77, but the
475 configuration had issues: these have also been resolved).
477 * The Windows 95/98/NT (W32) version of GNU make now has native support
478 for the Cygnus Cygwin release B20.1 shell (bash).
480 * The GNU make regression test suite, long available separately "under
481 the table", has been integrated into the release. You can invoke it
482 by running "make check" in the distribution. Note that it requires
483 Perl (either Perl 4 or Perl 5) to run.
487 * Implement BSD make's "?=" variable assignment operator. The variable
488 is assigned the specified value only if that variable is not already
491 * Make defines a new variable, "CURDIR", to contain the current working
492 directory (after the -C option, if any, has been processed).
493 Modifying this variable has no effect on the operation of make.
495 * Make defines a new default RCS rule, for new-style master file
496 storage: ``% :: RCS/%'' (note no ``,v'' suffix).
498 Make defines new default rules for DOS-style C++ file naming
499 conventions, with ``.cpp'' suffixes. All the same rules as for
500 ``.cc'' and ``.C'' suffixes are provided, along with LINK.cpp and
501 COMPILE.cpp macros (which default to the same value as LINK.cc and
502 COMPILE.cc). Note CPPFLAGS is still C preprocessor flags! You should
503 use CXXFLAGS to change C++ compiler flags.
505 * A new feature, "target-specific variable values", has been added.
506 This is a large change so please see the appropriate sections of the
507 manual for full details. Briefly, syntax like this:
509 TARGET: VARIABLE = VALUE
511 defines VARIABLE as VALUE within the context of TARGET. This is
512 similar to SunOS make's "TARGET := VARIABLE = VALUE" feature. Note
513 that the assignment may be of any type, not just recursive, and that
514 the override keyword is available.
516 COMPATIBILITY: This new syntax means that if you have any rules where
517 the first or second dependency has an equal sign (=) in its name,
518 you'll have to escape them with a backslash: "foo : bar\=baz".
519 Further, if you have any dependencies which already contain "\=",
520 you'll have to escape both of them: "foo : bar\\\=baz".
522 * A new appendix listing the most common error and warning messages
523 generated by GNU make, with some explanation, has been added to the
524 GNU make User's Manual.
526 * Updates to the GNU make Customs library support (see README.customs).
528 * Updates to the Windows 95/NT port from Rob Tulloh (see README.W32),
529 and to the DOS port from Eli Zaretski (see README.DOS).
533 * Small (but serious) bug fix. Quick rollout to get into the GNU source CD.
537 * GNU make now uses automake to control Makefile.in generation. This
538 should make it more consistent with the GNU standards.
540 * VPATH functionality has been changed to incorporate the VPATH+ patch,
541 previously maintained by Paul Smith <psmith@baynetworks.com>. See the
544 * Make defines a new variable, `MAKECMDGOALS', to contain the goals that
545 were specified on the command line, if any. Modifying this variable
546 has no effect on the operation of make.
548 * A new function, `$(wordlist S,E,TEXT)', is available: it returns a
549 list of words from number S to number E (inclusive) of TEXT.
551 * Instead of an error, detection of future modification times gives a
552 warning and continues. The warning is repeated just before GNU make
553 exits, so it is less likely to be lost.
555 * Fix the $(basename) and $(suffix) functions so they only operate on
556 the last filename, not the entire string:
558 Command Old Result New Result
559 ------- ---------- ----------
561 $(basename a.b/c) a a.b/c
563 $(suffix a.b/c) b/c <empty>
565 * The $(strip) function now removes newlines as well as TABs and spaces.
567 * The $(shell) function now changes CRLF (\r\n) pairs to a space as well
570 * Updates to the Windows 95/NT port from Rob Tulloh (see README.W32).
572 * Eli Zaretskii has updated the port to 32-bit protected mode on MSDOS
573 and MS-Windows, building with the DJGPP v2 port of GNU C/C++ compiler
574 and utilities. See README.DOS for details, and direct all questions
575 concerning this port to Eli Zaretskii <eliz@is.elta.co.il> or DJ
576 Delorie <dj@delorie.com>.
578 * John W. Eaton has updated the VMS port to support libraries and VPATH.
582 * The directory messages printed by `-w' and implicitly in sub-makes,
583 are now omitted if Make runs no commands and has no other messages to print.
585 * Make now detects files that for whatever reason have modification times
586 in the future and gives an error. Files with such impossible timestamps
587 can result from unsynchronized clocks, or archived distributions
588 containing bogus timestamps; they confuse Make's dependency engine
591 * The new directive `sinclude' is now recognized as another name for
592 `-include', for compatibility with some other Makes.
594 * Aaron Digulla has contributed a port to AmigaDOS. See README.Amiga for
595 details, and direct all Amiga-related questions to <digulla@fh-konstanz.de>.
597 * Rob Tulloh of Tivoli Systems has contributed a port to Windows NT or 95.
598 See README.W32 for details, and direct all Windows-related questions to
599 <rob_tulloh@tivoli.com>.
603 * Converted to use Autoconf version 2, so `configure' has some new options.
604 See INSTALL for details.
606 * You can now send a SIGUSR1 signal to Make to toggle printing of debugging
607 output enabled by -d, at any time during the run.
611 * DJ Delorie has ported Make to MS-DOS using the GO32 extender.
612 He is maintaining the DOS port, not the GNU Make maintainer;
613 please direct bugs and questions for DOS to <djgpp@sun.soe.clarkson.edu>.
614 MS-DOS binaries are available for FTP from ftp.simtel.net in
615 /pub/simtelnet/gnu/djgpp/.
617 * The `MAKEFLAGS' variable (in the environment or in a makefile) can now
618 contain variable definitions itself; these are treated just like
619 command line variable definitions. Make will automatically insert any
620 variable definitions from the environment value of `MAKEFLAGS' or from
621 the command line, into the `MAKEFLAGS' value exported to children. The
622 `MAKEOVERRIDES' variable previously included in the value of `$(MAKE)'
623 for sub-makes is now included in `MAKEFLAGS' instead. As before, you can
624 reset `MAKEOVERRIDES' in your makefile to avoid putting all the variables
625 in the environment when its size is limited.
627 * If `.DELETE_ON_ERROR' appears as a target, Make will delete the target of
628 a rule if it has changed when its recipe exits with a nonzero status,
629 just as when the recipe gets a signal.
631 * The automatic variable `$+' is new. It lists all the dependencies like
632 `$^', but preserves duplicates listed in the makefile. This is useful
633 for linking rules, where library files sometimes need to be listed twice
636 * You can now specify the `.IGNORE' and `.SILENT' special targets with
637 dependencies to limit their effects to those files. If a file appears as
638 a dependency of `.IGNORE', then errors will be ignored while running the
639 recipe to update that file. Likewise if a file appears as a dependency
640 of `.SILENT', then the recipe to update that file will not be printed
641 before it is run. (This change was made to conform to POSIX.2.)
645 * The automatic variables `$(@D)', `$(%D)', `$(*D)', `$(<D)', `$(?D)', and
646 `$(^D)' now omit the trailing slash from the directory name. (This change
647 was made to comply with POSIX.2.)
649 * The source distribution now includes the Info files for the Make manual.
650 There is no longer a separate distribution containing Info and DVI files.
652 * You can now set the variables `binprefix' and/or `manprefix' in
653 Makefile.in (or on the command line when installing) to install GNU make
654 under a name other than `make' (i.e., ``make binprefix=g install''
655 installs GNU make as `gmake').
657 * The built-in Texinfo rules use the new variables `TEXI2DVI_FLAGS' for
658 flags to the `texi2dvi' script, and `MAKEINFO_FLAGS' for flags to the
661 * The exit status of Make when it runs into errors is now 2 instead of 1.
662 The exit status is 1 only when using -q and some target is not up to date.
663 (This change was made to comply with POSIX.2.)
667 * It is no longer a fatal error to have a NUL character in a makefile.
668 You should never put a NUL in a makefile because it can have strange
669 results, but otherwise empty lines full of NULs (such as produced by
670 the `xmkmf' program) will always work fine.
672 * The error messages for nonexistent included makefiles now refer to the
673 makefile name and line number where the `include' appeared, so Emacs's
674 C-x ` command takes you there (in case it's a typo you need to fix).
678 * Implicit rule search for archive member references is now done in the
679 opposite order from previous versions: the whole target name `LIB(MEM)'
680 first, and just the member name and parentheses `(MEM)' second.
682 * Make now gives an error for an unterminated variable or function reference.
683 For example, `$(foo' with no matching `)' or `${bar' with no matching `}'.
685 * The new default variable `MAKE_VERSION' gives the version number of
686 Make, and a string describing the remote job support compiled in (if any).
687 Thus the value (in this release) is something like `3.69' or `3.69-Customs'.
689 * Commands in an invocation of the `shell' function are no longer run
690 with a modified environment like recipes are. As in versions before
691 3.68, they now run with the environment that `make' started with. We
692 have reversed the change made in version 3.68 because it turned out to
693 cause a paradoxical situation in cases like:
695 export variable = $(shell echo value)
697 When Make attempted to put this variable in the environment for a
698 recipe, it would try expand the value by running the shell command
699 `echo value'. In version 3.68, because it constructed an environment
700 for that shell command in the same way, Make would begin to go into an
701 infinite loop and then get a fatal error when it detected the loop.
703 * The recipe given for `.DEFAULT' is now used for phony targets with no
708 * You can list several archive member names inside parenthesis:
709 `lib(mem1 mem2 mem3)' is equivalent to `lib(mem1) lib(mem2) lib(mem3)'.
711 * You can use wildcards inside archive member references. For example,
712 `lib(*.o)' expands to all existing members of `lib' whose names end in
713 `.o' (e.g. `lib(a.o) lib(b.o)'); `*.a(*.o)' expands to all such members
714 of all existing files whose names end in `.a' (e.g. `foo.a(a.o)
715 foo.a(b.o) bar.a(c.o) bar.a(d.o)'.
717 * A suffix rule `.X.a' now produces two pattern rules:
718 (%.o): %.X # Previous versions produced only this.
719 %.a: %.X # Now produces this as well, just like other suffixes.
721 * The new flag `--warn-undefined-variables' says to issue a warning message
722 whenever Make expands a reference to an undefined variable.
724 * The new `-include' directive is just like `include' except that there is
725 no error (not even a warning) for a nonexistent makefile.
727 * Commands in an invocation of the `shell' function are now run with a
728 modified environment like recipes are, so you can use `export' et al
729 to set up variables for them. They used to run with the environment
730 that `make' started with.
734 * `make --version' (or `make -v') now exits immediately after printing
739 * Make now supports long-named members in `ar' archive files.
743 * Make now supports the `+=' syntax for a variable definition which appends
744 to the variable's previous value. See the section `Appending More Text
745 to Variables' in the manual for full details.
747 * The new option `--no-print-directory' inhibits the `-w' or
748 `--print-directory' feature. Make turns on `--print-directory'
749 automatically if you use `-C' or `--directory', and in sub-makes; some
750 users have found this behavior undesirable.
752 * The built-in implicit rules now support the alternative extension
753 `.txinfo' for Texinfo files, just like `.texinfo' and `.texi'.
757 * Make now uses a standard GNU `configure' script. See the new file
758 INSTALL for the new (and much simpler) installation procedure.
760 * There is now a shell script to build Make the first time, if you have no
761 other `make' program. `build.sh' is created by `configure'; see README.
763 * GNU Make now completely conforms to the POSIX.2 specification for `make'.
765 * Elements of the `$^' and `$?' automatic variables that are archive
766 member references now list only the member name, as in Unix and POSIX.2.
768 * You should no longer ever need to specify the `-w' switch, which prints
769 the current directory before and after Make runs. The `-C' switch to
770 change directory, and recursive use of Make, now set `-w' automatically.
772 * Multiple double-colon rules for the same target will no longer have their
773 recipes run simultaneously under -j, as this could result in the two
774 recipes trying to change the file at the same time and interfering with
777 * The `SHELL' variable is now never taken from the environment.
778 Each makefile that wants a shell other than the default (/bin/sh) must
779 set SHELL itself. SHELL is always exported to child processes.
780 This change was made for compatibility with POSIX.2.
782 * Make now accepts long options. There is now an informative usage message
783 that tells you what all the options are and what they do. Try `make --help'.
785 * There are two new directives: `export' and `unexport'. All variables are
786 no longer automatically put into the environments of the recipe lines that
787 Make runs. Instead, only variables specified on the command line or in
788 the environment are exported by default. To export others, use:
790 or you can define variables with:
791 export VARIABLE = VALUE
793 export VARIABLE := VALUE
797 .EXPORT_ALL_VARIABLES:
798 to get the old behavior. See the node `Variables/Recursion' in the manual
799 for a full description.
801 * The recipe from the `.DEFAULT' special target is only applied to
802 targets which have no rules at all, not all targets with no recipe.
803 This change was made for compatibility with Unix make.
805 * All fatal error messages now contain `***', so they are easy to find in
808 * Dependency file names like `-lNAME' are now replaced with the actual file
809 name found, as with files found by normal directory search (VPATH).
810 The library file `libNAME.a' may now be found in the current directory,
811 which is checked before VPATH; the standard set of directories (/lib,
812 /usr/lib, /usr/local/lib) is now checked last.
813 See the node `Libraries/Search' in the manual for full details.
815 * A single `include' directive can now specify more than one makefile to
818 You can also use shell file name patterns in an `include' directive:
821 * The default directories to search for included makefiles, and for
822 libraries specified with `-lNAME', are now set by configuration.
824 * You can now use blanks as well as colons to separate the directories in a
825 search path for the `vpath' directive or the `VPATH' variable.
827 * You can now use variables and functions in the left hand side of a
828 variable assignment, as in "$(foo)bar = value".
830 * The `MAKE' variable is always defined as `$(MAKE_COMMAND) $(MAKEOVERRIDES)'.
831 The `MAKE_COMMAND' variable is now defined to the name with which make
834 * The built-in rules for C++ compilation now use the variables `$(CXX)' and
835 `$(CXXFLAGS)' instead of `$(C++)' and `$(C++FLAGS)'. The old names had
836 problems with shells that cannot have `+' in environment variable names.
838 * The value of a recursively expanded variable is now expanded when putting
839 it into the environment for child processes. This change was made for
840 compatibility with Unix make.
842 * A rule with no targets before the `:' is now accepted and ignored.
843 This change was made for compatibility with SunOS 4 make.
844 We do not recommend that you write your makefiles to take advantage of this.
846 * The `-I' switch can now be used in MAKEFLAGS, and are put there
847 automatically just like other switches.
851 * Built-in rules for C++ source files with the `.C' suffix.
852 We still recommend that you use `.cc' instead.
854 * If a recipe is given too many times for a single target, the last one
855 given is used, and a warning message is printed.
857 * Error messages about makefiles are in standard GNU error format,
858 so C-x ` in Emacs works on them.
860 * Dependencies of pattern rules which contain no % need not actually exist
861 if they can be created (just like dependencies which do have a %).
865 * A message is always printed when Make decides there is nothing to be done.
866 It used to be that no message was printed for top-level phony targets
867 (because "`phony' is up to date" isn't quite right). Now a different
868 message "Nothing to be done for `phony'" is printed in that case.
870 * Archives on AIX now supposedly work.
872 * When the recipes specified for .DEFAULT are used to update a target,
873 the $< automatic variable is given the same value as $@ for that target.
874 This is how Unix make behaves, and this behavior is mandated by POSIX.2.
878 * The -n, -q, and -t options are not put in the `MAKEFLAGS' and `MFLAG'
879 variables while remaking makefiles, so recursive makes done while remaking
880 makefiles will behave properly.
882 * If the special target `.NOEXPORT' is specified in a makefile,
883 only variables that came from the environment and variables
884 defined on the command line are exported.
888 * Suffix rules may have dependencies (which are ignored).
892 * Dependencies of the form `-lLIB' are searched for as /usr/local/lib/libLIB.a
893 as well as libLIB.a in /usr/lib, /lib, the current directory, and VPATH.
897 * There is now a Unix man page for GNU Make. It is certainly not a
898 replacement for the Texinfo manual, but it documents the basic
899 functionality and the switches. For full documentation, you should
900 still read the Texinfo manual. Thanks to Dennis Morse of Stanford
901 University for contributing the initial version of this.
903 * Variables which are defined by default (e.g., `CC') will no longer be
904 put into the environment for child processes. (If these variables are
905 reset by the environment, makefiles, or the command line, they will
906 still go into the environment.)
908 * Makefiles which have recipes but no dependencies (and thus are always
909 considered out of date and in need of remaking), will not be remade (if they
910 were being remade only because they were makefiles). This means that GNU
911 Make will no longer go into an infinite loop when fed the makefiles that
912 `imake' (necessary to build X Windows) produces.
914 * There is no longer a warning for using the `vpath' directive with an explicit
915 pathname (instead of a `%' pattern).
919 * When removing intermediate files, only one `rm' command line is printed,
920 listing all file names.
922 * There are now automatic variables `$(^D)', `$(^F)', `$(?D)', and `$(?F)'.
923 These are the directory-only and file-only versions of `$^' and `$?'.
925 * Library dependencies given as `-lNAME' will use "libNAME.a" in the current
926 directory if it exists.
928 * The automatic variable `$($/)' is no longer defined.
930 * Leading `+' characters on a recipe line make that line be executed even
931 under -n, -t, or -q (as if the line contained `$(MAKE)').
933 * For recipe lines containing `$(MAKE)', `${MAKE}', or leading `+' characters,
934 only those lines are executed, not the entire recipe.
935 (This is how Unix make behaves for lines containing `$(MAKE)' or `${MAKE}'.)
939 * Filenames in rules will now have ~ and ~USER expanded.
941 * The `-p' output has been changed so it can be used as a makefile.
942 (All information that isn't specified by makefiles is prefaced with comment
947 * The % character can be quoted with backslash in implicit pattern rules,
948 static pattern rules, `vpath' directives, and `patsubst', `filter', and
949 `filter-out' functions. A warning is issued if a `vpath' directive's
950 pattern contains no %.
952 * The `wildcard' variable expansion function now expands ~ and ~USER.
954 * Messages indicating failed recipe lines now contain the target name:
955 make: *** [target] Error 1
957 * The `-p' output format has been changed somewhat to look more like
958 makefile rules and to give all information that Make has about files.
964 * The `-l' switch with no argument removes any previous load-average limit.
966 * When the `-w' switch is in effect, and Make has updated makefiles,
967 it will write a `Leaving directory' message before re-executing itself.
968 This makes the `directory change tracking' changes to Emacs's compilation
969 commands work properly.
973 * The automatic variable `$*' is now defined for explicit rules,
974 as it is in Unix make.
978 * The `-j' switch is now put in the MAKEFLAGS and MFLAGS variables when
979 specified without an argument (indicating infinite jobs).
980 The `-l' switch is not always put in the MAKEFLAGS and MFLAGS variables.
982 * Make no longer checks hashed directories after running recipes.
983 The behavior implemented in 3.41 caused too much slowdown.
987 * A dependency is NOT considered newer than its dependent if
988 they have the same modification time. The behavior implemented
989 in 3.43 conflicts with RCS.
993 * Dependency loops are no longer fatal errors.
995 * A dependency is considered newer than its dependent if
996 they have the same modification time.
1000 * The variables F77 and F77FLAGS are now set by default to $(FC) and
1001 $(FFLAGS). Makefiles designed for System V make may use these variables in
1002 explicit rules and expect them to be set. Unfortunately, there is no way to
1003 make setting these affect the Fortran implicit rules unless FC and FFLAGS
1004 are not used (and these are used by BSD make).
1008 * Make now checks to see if its hashed directories are changed by recipes.
1009 Other makes that hash directories (Sun, 4.3 BSD) don't do this.
1013 * The `shell' function no longer captures standard error output.
1017 * A file beginning with a dot can be the default target if it also contains
1018 a slash (e.g., `../bin/foo'). (Unix make allows this as well.)
1022 * Archive member names are truncated to 15 characters.
1024 * Yet more USG stuff.
1026 * Minimal support for Microport System V (a 16-bit machine and a
1027 brain-damaged compiler). This has even lower priority than other USG
1028 support, so if it gets beyond trivial, I will take it out completely.
1030 * Revamped default implicit rules (not much visible change).
1032 * The -d and -p options can come from the environment.
1036 * Improved support for USG and HPUX (hopefully).
1038 * A variable reference like `$(foo:a=b)', if `a' contains a `%', is
1039 equivalent to `$(patsubst a,b,$(foo))'.
1041 * Defining .DEFAULT with no deps or recipe clears its recipe.
1043 * New default implicit rules for .S (cpp, then as), and .sh (copy and
1044 make executable). All default implicit rules that use cpp (even
1045 indirectly), use $(CPPFLAGS).
1049 * Giving the -j option with no arguments gives you infinite jobs.
1053 * New option: "-l LOAD" says not to start any new jobs while others are
1054 running if the load average is not below LOAD (a floating-point number).
1056 * There is support in place for implementations of remote command execution
1057 in Make. See the file remote.c.
1061 * No more than 10 directories will be kept open at once.
1062 (This number can be changed by redefining MAX_OPEN_DIRECTORIES in dir.c.)
1066 * Archive files will have their modification times recorded before doing
1067 anything that might change their modification times by updating an archive
1072 * The `MAKELEVEL' variable is defined for use by makefiles.
1076 * The recursion level indications in error messages are much shorter than
1077 they were in version 3.14.
1081 * Leading spaces before directives are ignored (as documented).
1083 * Included makefiles can determine the default goal target.
1084 (System V Make does it this way, so we are being compatible).
1088 * Variables that are defaults built into Make will not be put in the
1089 environment for children. This just saves some environment space and,
1090 except under -e, will be transparent to sub-makes.
1092 * Error messages from sub-makes will indicate the level of recursion.
1094 * Hopefully some speed-up for large directories due to a change in the
1095 directory hashing scheme.
1097 * One child will always get a standard input that is usable.
1099 * Default makefiles that don't exist will be remade and read in.
1103 * Count parentheses inside expansion function calls so you can
1104 have nested calls: `$(sort $(foreach x,a b,$(x)))'.
1108 * Several bug fixes, including USG and Sun386i support.
1110 * `shell' function to expand shell commands a la `
1112 * If the `-d' flag is given, version information will be printed.
1114 * The `-c' option has been renamed to `-C' for compatibility with tar.
1116 * The `-p' option no longer inhibits other normal operation.
1118 * Makefiles will be updated and re-read if necessary.
1120 * Can now run several recipes at once (parallelism), -j option.
1122 * Error messages will contain the level of Make recursion, if any.
1124 * The `MAKEFLAGS' and `MFLAGS' variables will be scanned for options after
1127 * A double-colon rule with no dependencies will always have its recipe run.
1128 (This is how both the BSD and System V versions of Make do it.)
1132 (Changes from versions 1 through 3.05 were never recorded. Sorry.)
1134 -------------------------------------------------------------------------------
1135 Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
1136 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
1137 2010 Free Software Foundation, Inc. This file is part of GNU Make.
1139 GNU Make is free software; you can redistribute it and/or modify it under the
1140 terms of the GNU General Public License as published by the Free Software
1141 Foundation; either version 3 of the License, or (at your option) any later
1144 GNU Make is distributed in the hope that it will be useful, but WITHOUT ANY
1145 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
1146 A PARTICULAR PURPOSE. See the GNU General Public License for more details.
1148 You should have received a copy of the GNU General Public License along with
1149 this program. If not, see <http://www.gnu.org/licenses/>.