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 * Compiling GNU make now requires a conforming ISO C 1989 compiler and
15 standard runtime library.
17 * WARNING: Backward-incompatibility!
18 The '$?' variable now contains all prerequisites that caused the target to
19 be considered out of date, even if they do not exist (previously only
20 existing targets were provided in $?).
22 * WARNING: Backward-incompatibility!
23 As a result of parser enhancements, two backward-compatibility issues exist:
24 first, a prerequisite containing an "=" cannot be escaped with a backslash
25 any longer. You must create a variable containing an "=" and use that
26 variable in the prerequisite. Second, variable names can no longer contain
27 whitespace, unless you put the whitespace in a variable and use the
30 * WARNING: Backward-incompatibility!
31 The pattern-specific variables and pattern rules are now applied in the
32 shortest stem first order instead of the definition order (variables
33 and rules with the same stem length are still applied in the definition
34 order). This produces the usually-desired behavior where more specific
35 patterns are preferred. To detect this feature search for 'shortest-stem'
36 in the .FEATURES special variable.
38 * New command line option: --eval=STRING causes STRING to be evaluated as
39 makefile syntax (akin to using the $(eval ...) function). The evaluation is
40 performed after all default rules and variables are defined, but before any
43 * New special variable: .RECIPEPREFIX allows you to reset the recipe
44 introduction character from the default (TAB) to something else. The first
45 character of this variable value is the new recipe introduction character.
46 If the variable is set to the empty string, TAB is used again. It can be
47 set and reset at will; recipes will use the value active when they were
48 first parsed. To detect this feature check the value of $(.RECIPEPREFIX).
50 * New variable modifier 'private': prefixing a variable assignment with the
51 modifier 'private' suppresses inheritance of that variable by
52 prerequisites. This is most useful for target- and pattern-specific
55 * New make directive: 'undefine' allows you to undefine a variable so
56 that it appears as if it was never set. Both $(flavor) and $(origin)
57 functions will return 'undefined' for such a variable. To detect this
58 feature search for 'undefine in the .FEATURES special variable.
60 * The parser for variable assignments has been enhanced to allow multiple
61 modifiers ('export', 'override', 'private') on the same line as variables,
62 including define/endef variables, and in any order. Also, it is possible
63 to create variables and targets named as these modifiers.
68 * GNU make is ported to OS/2.
70 * GNU make is ported to MinGW. The MinGW build is only supported by
71 the build_w32.bat batch file; see the file README.W32 for more
74 * WARNING: Future backward-incompatibility!
75 Up to and including this release, the '$?' variable does not contain
76 any prerequisite that does not exist, even though that prerequisite
77 might have caused the target to rebuild. Starting with the _next_
78 release of GNU make, '$?' will contain all prerequisites that caused
79 the target to be considered out of date. See this Savannah bug:
80 http://savannah.gnu.org/bugs/index.php?func=detailitem&item_id=16051
82 * WARNING: Backward-incompatibility!
83 GNU make now implements a generic "second expansion" feature on the
84 prerequisites of both explicit and implicit (pattern) rules. In order
85 to enable this feature, the special target '.SECONDEXPANSION' must be
86 defined before the first target which takes advantage of it. If this
87 feature is enabled then after all rules have been parsed the
88 prerequisites are expanded again, this time with all the automatic
89 variables in scope. This means that in addition to using standard
90 SysV $$@ in prerequisites lists, you can also use complex functions
91 such as $$(notdir $$@) etc. This behavior applies to implicit rules,
92 as well, where the second expansion occurs when the rule is matched.
93 However, this means that when '.SECONDEXPANSION' is enabled you must
94 double-quote any "$" in your filenames; instead of "foo: boo$$bar" you
95 now must write "foo: foo$$$$bar". Note that the SysV $$@ etc. feature,
96 which used to be available by default, is now ONLY available when the
97 .SECONDEXPANSION target is defined. If your makefiles take advantage
98 of this SysV feature you will need to update them.
100 * WARNING: Backward-incompatibility!
102 In order to comply with POSIX, the way in which GNU make processes
103 backslash-newline sequences in recipes has changed. If your makefiles
104 use backslash-newline sequences inside of single-quoted strings in
105 recipes you will be impacted by this change. See the GNU make manual
106 subsection "Splitting Recipe Lines" (node "Splitting Lines"), in
107 section "Recipe Syntax", chapter "Writing Recipe in Rules", for
110 * WARNING: Backward-incompatibility!
111 Some previous versions of GNU make had a bug where "#" in a function
112 invocation such as $(shell ...) was treated as a make comment. A
113 workaround was to escape these with backslashes. This bug has been
114 fixed: if your makefile uses "\#" in a function invocation the
115 backslash is now preserved, so you'll need to remove it.
117 * New command line option: -L (--check-symlink-times). On systems that
118 support symbolic links, if this option is given then GNU make will
119 use the most recent modification time of any symbolic links that are
120 used to resolve target files. The default behavior remains as it
121 always has: use the modification time of the actual target file only.
123 * The "else" conditional line can now be followed by any other valid
124 conditional on the same line: this does not increase the depth of the
125 conditional nesting, so only one "endif" is required to close the
128 * All pattern-specific variables that match a given target are now used
129 (previously only the first match was used).
131 * Target-specific variables can be marked as exportable using the
134 * In a recursive $(call ...) context, any extra arguments from the outer
135 call are now masked in the context of the inner call.
137 * Implemented a solution for the "thundering herd" problem with "-j -l".
138 This version of GNU make uses an algorithm suggested by Thomas Riedl
139 <thomas.riedl@siemens.com> to track the number of jobs started in the
140 last second and artificially adjust GNU make's view of the system's
141 load average accordingly.
143 * New special variables available in this release:
144 - .INCLUDE_DIRS: Expands to a list of directories that make searches
145 for included makefiles.
146 - .FEATURES: Contains a list of special features available in this
148 - .DEFAULT_GOAL: Set the name of the default goal make will
149 use if no goals are provided on the command line.
150 - MAKE_RESTARTS: If set, then this is the number of times this
151 instance of make has been restarted (see "How Makefiles Are Remade"
153 - New automatic variable: $| (added in 3.80, actually): contains all
154 the order-only prerequisites defined for the target.
156 * New functions available in this release:
157 - $(lastword ...) returns the last word in the list. This gives
158 identical results as $(word $(words ...) ...), but is much faster.
159 - $(abspath ...) returns the absolute path (all "." and ".."
160 directories resolved, and any duplicate "/" characters removed) for
162 - $(realpath ...) returns the canonical pathname for each path
163 provided. The canonical pathname is the absolute pathname, with
164 all symbolic links resolved as well.
165 - $(info ...) prints its arguments to stdout. No makefile name or
166 line number info, etc. is printed.
167 - $(flavor ...) returns the flavor of a variable.
168 - $(or ...) provides a short-circuiting OR conditional: each argument
169 is expanded. The first true (non-empty) argument is returned; no
170 further arguments are expanded. Expands to empty if there are no
172 - $(and ...) provides a short-circuiting AND conditional: each
173 argument is expanded. The first false (empty) argument is
174 returned; no further arguments are expanded. Expands to the last
175 argument if all arguments are true.
177 * Changes made for POSIX compatibility:
178 - Only touch targets (under -t) if they have a recipe.
179 - Setting the SHELL make variable does NOT change the value of the
180 SHELL environment variable given to programs invoked by make. As
181 an enhancement to POSIX, if you export the make variable SHELL then
182 it will be set in the environment, just as before.
184 * On MS Windows systems, explicitly setting SHELL to a pathname ending
185 in "cmd" or "cmd.exe" (case-insensitive) will force GNU make to use
186 the DOS command interpreter in batch mode even if a UNIX-like shell
187 could be found on the system.
189 * On VMS there is now support for case-sensitive filesystems such as ODS5.
190 See the readme.vms file for information.
192 * Parallel builds (-jN) no longer require a working Bourne shell on
193 Windows platforms. They work even with the stock Windows shells, such
194 as cmd.exe and command.com.
196 * Updated to autoconf 2.59, automake 1.9.5, and gettext 0.14.1. Users
197 should not be impacted.
199 * New translations for Swedish, Chinese (simplified), Ukrainian,
200 Belarusian, Finnish, Kinyarwandan, and Irish. Many updated
203 A complete list of bugs fixed in this version is available here:
205 http://savannah.gnu.org/bugs/index.php?group=make&report_id=111&fix_release_id=103
210 * A new feature exists: order-only prerequisites. These prerequisites
211 affect the order in which targets are built, but they do not impact
212 the rebuild/no-rebuild decision of their dependents. That is to say,
213 they allow you to require target B be built before target A, without
214 requiring that target A will always be rebuilt if target B is updated.
215 Patch for this feature provided by Greg McGary <greg@mcgary.org>.
217 * For compatibility with SysV make, GNU make now supports the peculiar
218 syntax $$@, $$(@D), and $$(@F) in the prerequisites list of a rule.
219 This syntax is only valid within explicit and static pattern rules: it
220 cannot be used in implicit (suffix or pattern) rules. Edouard G. Parmelan
221 <egp@free.fr> provided a patch implementing this feature; however, I
222 decided to implement it in a different way.
224 * The argument to the "ifdef" conditional is now expanded before it's
225 tested, so it can be a constructed variable name.
227 Similarly, the arguments to "export" (when not used in a variable
228 definition context) and "unexport" are also now expanded.
230 * A new function is defined: $(value ...). The argument to this
231 function is the _name_ of a variable. The result of the function is
232 the value of the variable, without having been expanded.
234 * A new function is defined: $(eval ...). The arguments to this
235 function should expand to makefile commands, which will then be
236 evaluated as if they had appeared in the makefile. In combination
237 with define/endef multiline variable definitions this is an extremely
238 powerful capability. The $(value ...) function is also sometimes
241 * A new built-in variable is defined, $(MAKEFILE_LIST). It contains a
242 list of each makefile GNU make has read, or started to read, in the
243 order in which they were encountered. So, the last filename in the
244 list when a makefile is just being read (before any includes) is the
245 name of the current makefile.
247 * A new built-in variable is defined: $(.VARIABLES). When it is
248 expanded it returns a complete list of variable names defined by all
249 makefiles at that moment.
251 * A new command line option is defined, -B or --always-make. If
252 specified GNU make will consider all targets out-of-date even if they
253 would otherwise not be.
255 * The arguments to $(call ...) functions were being stored in $1, $2,
256 etc. as recursive variables, even though they are fully expanded
257 before assignment. This means that escaped dollar signs ($$ etc.)
258 were not behaving properly. Now the arguments are stored as simple
259 variables. This may mean that if you added extra escaping to your
260 $(call ...) function arguments you will need to undo it now.
262 * The variable invoked by $(call ...) can now be recursive: unlike other
263 variables it can reference itself and this will not produce an error
264 when it is used as the first argument to $(call ...) (but only then).
266 * New pseudo-target .LOW_RESOLUTION_TIME, superseding the configure
267 option --disable-nsec-timestamps. You might need this if your build
268 process depends on tools like "cp -p" preserving time stamps, since
269 "cp -p" (right now) doesn't preserve the subsecond portion of a time
272 * Updated translations for French, Galician, German, Japanese, Korean,
273 and Russian. New translations for Croatian, Danish, Hebrew, and
276 * Updated internationalization support to Gettext 0.11.5.
277 GNU make now uses Gettext's "external" feature, and does not include
278 any internationalization code itself. Configure will search your
279 system for an existing implementation of GNU Gettext (only GNU Gettext
280 is acceptable) and use it if it exists. If not, NLS will be disabled.
281 See ABOUT-NLS for more information.
283 * Updated to autoconf 2.54 and automake 1.7. Users should not be impacted.
285 A complete list of bugs fixed in this version is available here:
287 http://savannah.gnu.org/bugs/index.php?group=make&report_id=111&fix_release_id=102
292 * .SECONDARY with no prerequisites now prevents any target from being
293 removed because make thinks it's an intermediate file, not just those
294 listed in the makefile.
296 * New configure option --disable-nsec-timestamps, but this was
297 superseded in later versions by the .LOW_RESOLUTION_TIME pseudo-target.
301 * GNU make optionally supports internationalization and locales via the
302 GNU gettext (or local gettext if suitable) package. See the ABOUT-NLS
303 file for more information on configuring GNU make for NLS.
305 * Previously, GNU make quoted variables such as MAKEFLAGS and
306 MAKEOVERRIDES for proper parsing by the shell. This allowed them to
307 be used within make build scripts. However, using them there is not
308 proper behavior: they are meant to be passed to subshells via the
309 environment. Unfortunately the values were not quoted properly to be
310 passed through the environment. This meant that make didn't properly
311 pass some types of command line values to submakes.
313 With this version we change that behavior: now these variables are
314 quoted properly for passing through the environment, which is the
315 correct way to do it. If you previously used these variables
316 explicitly within a make rule you may need to re-examine your use for
317 correctness given this change.
319 * A new pseudo-target .NOTPARALLEL is available. If defined, the
320 current makefile is run serially regardless of the value of -j.
321 However, submakes are still eligible for parallel execution.
323 * The --debug option has changed: it now allows optional flags
324 controlling the amount and type of debugging output. By default only
325 a minimal amount information is generated, displaying the names of
326 "normal" targets (not makefiles) that were deemed out of date and in
327 need of being rebuilt.
329 Note that the -d option behaves as before: it takes no arguments and
330 all debugging information is generated.
332 * The `-p' (print database) output now includes filename and linenumber
333 information for variable definitions, to aid debugging.
335 * The wordlist function no longer reverses its arguments if the "start"
336 value is greater than the "end" value. If that's true, nothing is
339 * Hartmut Becker provided many updates for the VMS port of GNU make.
340 See the readme.vms file for more details.
344 * Two new functions, $(error ...) and $(warning ...) are available. The
345 former will cause make to fail and exit immediately upon expansion of
346 the function, with the text provided as the error message. The latter
347 causes the text provided to be printed as a warning message, but make
350 * A new function $(call ...) is available. This allows users to create
351 their own parameterized macros and invoke them later. Original
352 implementation of this function was provided by Han-Wen Nienhuys
355 * A new function $(if ...) is available. It provides if-then-else
356 capabilities in a builtin function. Original implementation of this
357 function was provided by Han-Wen Nienhuys <hanwen@cs.uu.nl>.
359 * Make defines a new variable, .LIBPATTERNS. This variable controls how
360 library dependency expansion (dependencies like ``-lfoo'') is performed.
362 * Make accepts CRLF sequences as well as traditional LF, for
363 compatibility with makefiles created on other operating systems.
365 * Make accepts a new option: -R, or --no-builtin-variables. This option
366 disables the definition of the rule-specific builtin variables (CC,
367 LD, AR, etc.). Specifying this option forces -r (--no-builtin-rules)
370 * A "job server" feature, suggested by Howard Chu <hyc@highlandsun.com>.
372 On systems that support POSIX pipe(2) semantics, GNU make can now pass
373 -jN options to submakes rather than forcing them all to use -j1. The
374 top make and all its sub-make processes use a pipe to communicate with
375 each other to ensure that no more than N jobs are started across all
376 makes. To get the old behavior of -j back, you can configure make
377 with the --disable-job-server option.
379 * The confusing term "dependency" has been replaced by the more accurate
380 and standard term "prerequisite", both in the manual and in all GNU make
383 * GNU make supports the "big archive" library format introduced in AIX 4.3.
385 * GNU make supports large files on AIX, HP-UX, and IRIX. These changes
386 were provided by Paul Eggert <eggert@twinsun.com>. (Large file
387 support for Solaris and Linux was introduced in 3.77, but the
388 configuration had issues: these have also been resolved).
390 * The Windows 95/98/NT (W32) version of GNU make now has native support
391 for the Cygnus Cygwin release B20.1 shell (bash).
393 * The GNU make regression test suite, long available separately "under
394 the table", has been integrated into the release. You can invoke it
395 by running "make check" in the distribution. Note that it requires
396 Perl (either Perl 4 or Perl 5) to run.
400 * Implement BSD make's "?=" variable assignment operator. The variable
401 is assigned the specified value only if that variable is not already
404 * Make defines a new variable, "CURDIR", to contain the current working
405 directory (after the -C option, if any, has been processed).
406 Modifying this variable has no effect on the operation of make.
408 * Make defines a new default RCS rule, for new-style master file
409 storage: ``% :: RCS/%'' (note no ``,v'' suffix).
411 Make defines new default rules for DOS-style C++ file naming
412 conventions, with ``.cpp'' suffixes. All the same rules as for
413 ``.cc'' and ``.C'' suffixes are provided, along with LINK.cpp and
414 COMPILE.cpp macros (which default to the same value as LINK.cc and
415 COMPILE.cc). Note CPPFLAGS is still C preprocessor flags! You should
416 use CXXFLAGS to change C++ compiler flags.
418 * A new feature, "target-specific variable values", has been added.
419 This is a large change so please see the appropriate sections of the
420 manual for full details. Briefly, syntax like this:
422 TARGET: VARIABLE = VALUE
424 defines VARIABLE as VALUE within the context of TARGET. This is
425 similar to SunOS make's "TARGET := VARIABLE = VALUE" feature. Note
426 that the assignment may be of any type, not just recursive, and that
427 the override keyword is available.
429 COMPATIBILITY: This new syntax means that if you have any rules where
430 the first or second dependency has an equal sign (=) in its name,
431 you'll have to escape them with a backslash: "foo : bar\=baz".
432 Further, if you have any dependencies which already contain "\=",
433 you'll have to escape both of them: "foo : bar\\\=baz".
435 * A new appendix listing the most common error and warning messages
436 generated by GNU make, with some explanation, has been added to the
437 GNU make User's Manual.
439 * Updates to the GNU make Customs library support (see README.customs).
441 * Updates to the Windows 95/NT port from Rob Tulloh (see README.W32),
442 and to the DOS port from Eli Zaretski (see README.DOS).
446 * Small (but serious) bug fix. Quick rollout to get into the GNU source CD.
450 * GNU make now uses automake to control Makefile.in generation. This
451 should make it more consistent with the GNU standards.
453 * VPATH functionality has been changed to incorporate the VPATH+ patch,
454 previously maintained by Paul Smith <psmith@baynetworks.com>. See the
457 * Make defines a new variable, `MAKECMDGOALS', to contain the goals that
458 were specified on the command line, if any. Modifying this variable
459 has no effect on the operation of make.
461 * A new function, `$(wordlist S,E,TEXT)', is available: it returns a
462 list of words from number S to number E (inclusive) of TEXT.
464 * Instead of an error, detection of future modification times gives a
465 warning and continues. The warning is repeated just before GNU make
466 exits, so it is less likely to be lost.
468 * Fix the $(basename) and $(suffix) functions so they only operate on
469 the last filename, not the entire string:
471 Command Old Result New Result
472 ------- ---------- ----------
474 $(basename a.b/c) a a.b/c
476 $(suffix a.b/c) b/c <empty>
478 * The $(strip) function now removes newlines as well as TABs and spaces.
480 * The $(shell) function now changes CRLF (\r\n) pairs to a space as well
483 * Updates to the Windows 95/NT port from Rob Tulloh (see README.W32).
485 * Eli Zaretskii has updated the port to 32-bit protected mode on MSDOS
486 and MS-Windows, building with the DJGPP v2 port of GNU C/C++ compiler
487 and utilities. See README.DOS for details, and direct all questions
488 concerning this port to Eli Zaretskii <eliz@is.elta.co.il> or DJ
489 Delorie <dj@delorie.com>.
491 * John W. Eaton has updated the VMS port to support libraries and VPATH.
495 * The directory messages printed by `-w' and implicitly in sub-makes,
496 are now omitted if Make runs no commands and has no other messages to print.
498 * Make now detects files that for whatever reason have modification times
499 in the future and gives an error. Files with such impossible timestamps
500 can result from unsynchronized clocks, or archived distributions
501 containing bogus timestamps; they confuse Make's dependency engine
504 * The new directive `sinclude' is now recognized as another name for
505 `-include', for compatibility with some other Makes.
507 * Aaron Digulla has contributed a port to AmigaDOS. See README.Amiga for
508 details, and direct all Amiga-related questions to <digulla@fh-konstanz.de>.
510 * Rob Tulloh of Tivoli Systems has contributed a port to Windows NT or 95.
511 See README.W32 for details, and direct all Windows-related questions to
512 <rob_tulloh@tivoli.com>.
516 * Converted to use Autoconf version 2, so `configure' has some new options.
517 See INSTALL for details.
519 * You can now send a SIGUSR1 signal to Make to toggle printing of debugging
520 output enabled by -d, at any time during the run.
524 * DJ Delorie has ported Make to MS-DOS using the GO32 extender.
525 He is maintaining the DOS port, not the GNU Make maintainer;
526 please direct bugs and questions for DOS to <djgpp@sun.soe.clarkson.edu>.
527 MS-DOS binaries are available for FTP from ftp.simtel.net in
528 /pub/simtelnet/gnu/djgpp/.
530 * The `MAKEFLAGS' variable (in the environment or in a makefile) can now
531 contain variable definitions itself; these are treated just like
532 command line variable definitions. Make will automatically insert any
533 variable definitions from the environment value of `MAKEFLAGS' or from
534 the command line, into the `MAKEFLAGS' value exported to children. The
535 `MAKEOVERRIDES' variable previously included in the value of `$(MAKE)'
536 for sub-makes is now included in `MAKEFLAGS' instead. As before, you can
537 reset `MAKEOVERRIDES' in your makefile to avoid putting all the variables
538 in the environment when its size is limited.
540 * If `.DELETE_ON_ERROR' appears as a target, Make will delete the target of
541 a rule if it has changed when its recipe exits with a nonzero status,
542 just as when the recipe gets a signal.
544 * The automatic variable `$+' is new. It lists all the dependencies like
545 `$^', but preserves duplicates listed in the makefile. This is useful
546 for linking rules, where library files sometimes need to be listed twice
549 * You can now specify the `.IGNORE' and `.SILENT' special targets with
550 dependencies to limit their effects to those files. If a file appears as
551 a dependency of `.IGNORE', then errors will be ignored while running the
552 recipe to update that file. Likewise if a file appears as a dependency
553 of `.SILENT', then the recipe to update that file will not be printed
554 before it is run. (This change was made to conform to POSIX.2.)
558 * The automatic variables `$(@D)', `$(%D)', `$(*D)', `$(<D)', `$(?D)', and
559 `$(^D)' now omit the trailing slash from the directory name. (This change
560 was made to comply with POSIX.2.)
562 * The source distribution now includes the Info files for the Make manual.
563 There is no longer a separate distribution containing Info and DVI files.
565 * You can now set the variables `binprefix' and/or `manprefix' in
566 Makefile.in (or on the command line when installing) to install GNU make
567 under a name other than `make' (i.e., ``make binprefix=g install''
568 installs GNU make as `gmake').
570 * The built-in Texinfo rules use the new variables `TEXI2DVI_FLAGS' for
571 flags to the `texi2dvi' script, and `MAKEINFO_FLAGS' for flags to the
574 * The exit status of Make when it runs into errors is now 2 instead of 1.
575 The exit status is 1 only when using -q and some target is not up to date.
576 (This change was made to comply with POSIX.2.)
580 * It is no longer a fatal error to have a NUL character in a makefile.
581 You should never put a NUL in a makefile because it can have strange
582 results, but otherwise empty lines full of NULs (such as produced by
583 the `xmkmf' program) will always work fine.
585 * The error messages for nonexistent included makefiles now refer to the
586 makefile name and line number where the `include' appeared, so Emacs's
587 C-x ` command takes you there (in case it's a typo you need to fix).
591 * Implicit rule search for archive member references is now done in the
592 opposite order from previous versions: the whole target name `LIB(MEM)'
593 first, and just the member name and parentheses `(MEM)' second.
595 * Make now gives an error for an unterminated variable or function reference.
596 For example, `$(foo' with no matching `)' or `${bar' with no matching `}'.
598 * The new default variable `MAKE_VERSION' gives the version number of
599 Make, and a string describing the remote job support compiled in (if any).
600 Thus the value (in this release) is something like `3.69' or `3.69-Customs'.
602 * Commands in an invocation of the `shell' function are no longer run
603 with a modified environment like recipes are. As in versions before
604 3.68, they now run with the environment that `make' started with. We
605 have reversed the change made in version 3.68 because it turned out to
606 cause a paradoxical situation in cases like:
608 export variable = $(shell echo value)
610 When Make attempted to put this variable in the environment for a
611 recipe, it would try expand the value by running the shell command
612 `echo value'. In version 3.68, because it constructed an environment
613 for that shell command in the same way, Make would begin to go into an
614 infinite loop and then get a fatal error when it detected the loop.
616 * The recipe given for `.DEFAULT' is now used for phony targets with no
621 * You can list several archive member names inside parenthesis:
622 `lib(mem1 mem2 mem3)' is equivalent to `lib(mem1) lib(mem2) lib(mem3)'.
624 * You can use wildcards inside archive member references. For example,
625 `lib(*.o)' expands to all existing members of `lib' whose names end in
626 `.o' (e.g. `lib(a.o) lib(b.o)'); `*.a(*.o)' expands to all such members
627 of all existing files whose names end in `.a' (e.g. `foo.a(a.o)
628 foo.a(b.o) bar.a(c.o) bar.a(d.o)'.
630 * A suffix rule `.X.a' now produces two pattern rules:
631 (%.o): %.X # Previous versions produced only this.
632 %.a: %.X # Now produces this as well, just like other suffixes.
634 * The new flag `--warn-undefined-variables' says to issue a warning message
635 whenever Make expands a reference to an undefined variable.
637 * The new `-include' directive is just like `include' except that there is
638 no error (not even a warning) for a nonexistent makefile.
640 * Commands in an invocation of the `shell' function are now run with a
641 modified environment like recipes are, so you can use `export' et al
642 to set up variables for them. They used to run with the environment
643 that `make' started with.
647 * `make --version' (or `make -v') now exits immediately after printing
652 * Make now supports long-named members in `ar' archive files.
656 * Make now supports the `+=' syntax for a variable definition which appends
657 to the variable's previous value. See the section `Appending More Text
658 to Variables' in the manual for full details.
660 * The new option `--no-print-directory' inhibits the `-w' or
661 `--print-directory' feature. Make turns on `--print-directory'
662 automatically if you use `-C' or `--directory', and in sub-makes; some
663 users have found this behavior undesirable.
665 * The built-in implicit rules now support the alternative extension
666 `.txinfo' for Texinfo files, just like `.texinfo' and `.texi'.
670 * Make now uses a standard GNU `configure' script. See the new file
671 INSTALL for the new (and much simpler) installation procedure.
673 * There is now a shell script to build Make the first time, if you have no
674 other `make' program. `build.sh' is created by `configure'; see README.
676 * GNU Make now completely conforms to the POSIX.2 specification for `make'.
678 * Elements of the `$^' and `$?' automatic variables that are archive
679 member references now list only the member name, as in Unix and POSIX.2.
681 * You should no longer ever need to specify the `-w' switch, which prints
682 the current directory before and after Make runs. The `-C' switch to
683 change directory, and recursive use of Make, now set `-w' automatically.
685 * Multiple double-colon rules for the same target will no longer have their
686 recipes run simultaneously under -j, as this could result in the two
687 recipes trying to change the file at the same time and interfering with
690 * The `SHELL' variable is now never taken from the environment.
691 Each makefile that wants a shell other than the default (/bin/sh) must
692 set SHELL itself. SHELL is always exported to child processes.
693 This change was made for compatibility with POSIX.2.
695 * Make now accepts long options. There is now an informative usage message
696 that tells you what all the options are and what they do. Try `make --help'.
698 * There are two new directives: `export' and `unexport'. All variables are
699 no longer automatically put into the environments of the recipe lines that
700 Make runs. Instead, only variables specified on the command line or in
701 the environment are exported by default. To export others, use:
703 or you can define variables with:
704 export VARIABLE = VALUE
706 export VARIABLE := VALUE
710 .EXPORT_ALL_VARIABLES:
711 to get the old behavior. See the node `Variables/Recursion' in the manual
712 for a full description.
714 * The recipe from the `.DEFAULT' special target is only applied to
715 targets which have no rules at all, not all targets with no recipe.
716 This change was made for compatibility with Unix make.
718 * All fatal error messages now contain `***', so they are easy to find in
721 * Dependency file names like `-lNAME' are now replaced with the actual file
722 name found, as with files found by normal directory search (VPATH).
723 The library file `libNAME.a' may now be found in the current directory,
724 which is checked before VPATH; the standard set of directories (/lib,
725 /usr/lib, /usr/local/lib) is now checked last.
726 See the node `Libraries/Search' in the manual for full details.
728 * A single `include' directive can now specify more than one makefile to
731 You can also use shell file name patterns in an `include' directive:
734 * The default directories to search for included makefiles, and for
735 libraries specified with `-lNAME', are now set by configuration.
737 * You can now use blanks as well as colons to separate the directories in a
738 search path for the `vpath' directive or the `VPATH' variable.
740 * You can now use variables and functions in the left hand side of a
741 variable assignment, as in "$(foo)bar = value".
743 * The `MAKE' variable is always defined as `$(MAKE_COMMAND) $(MAKEOVERRIDES)'.
744 The `MAKE_COMMAND' variable is now defined to the name with which make
747 * The built-in rules for C++ compilation now use the variables `$(CXX)' and
748 `$(CXXFLAGS)' instead of `$(C++)' and `$(C++FLAGS)'. The old names had
749 problems with shells that cannot have `+' in environment variable names.
751 * The value of a recursively expanded variable is now expanded when putting
752 it into the environment for child processes. This change was made for
753 compatibility with Unix make.
755 * A rule with no targets before the `:' is now accepted and ignored.
756 This change was made for compatibility with SunOS 4 make.
757 We do not recommend that you write your makefiles to take advantage of this.
759 * The `-I' switch can now be used in MAKEFLAGS, and are put there
760 automatically just like other switches.
764 * Built-in rules for C++ source files with the `.C' suffix.
765 We still recommend that you use `.cc' instead.
767 * If a recipe is given too many times for a single target, the last one
768 given is used, and a warning message is printed.
770 * Error messages about makefiles are in standard GNU error format,
771 so C-x ` in Emacs works on them.
773 * Dependencies of pattern rules which contain no % need not actually exist
774 if they can be created (just like dependencies which do have a %).
778 * A message is always printed when Make decides there is nothing to be done.
779 It used to be that no message was printed for top-level phony targets
780 (because "`phony' is up to date" isn't quite right). Now a different
781 message "Nothing to be done for `phony'" is printed in that case.
783 * Archives on AIX now supposedly work.
785 * When the recipes specified for .DEFAULT are used to update a target,
786 the $< automatic variable is given the same value as $@ for that target.
787 This is how Unix make behaves, and this behavior is mandated by POSIX.2.
791 * The -n, -q, and -t options are not put in the `MAKEFLAGS' and `MFLAG'
792 variables while remaking makefiles, so recursive makes done while remaking
793 makefiles will behave properly.
795 * If the special target `.NOEXPORT' is specified in a makefile,
796 only variables that came from the environment and variables
797 defined on the command line are exported.
801 * Suffix rules may have dependencies (which are ignored).
805 * Dependencies of the form `-lLIB' are searched for as /usr/local/lib/libLIB.a
806 as well as libLIB.a in /usr/lib, /lib, the current directory, and VPATH.
810 * There is now a Unix man page for GNU Make. It is certainly not a
811 replacement for the Texinfo manual, but it documents the basic
812 functionality and the switches. For full documentation, you should
813 still read the Texinfo manual. Thanks to Dennis Morse of Stanford
814 University for contributing the initial version of this.
816 * Variables which are defined by default (e.g., `CC') will no longer be
817 put into the environment for child processes. (If these variables are
818 reset by the environment, makefiles, or the command line, they will
819 still go into the environment.)
821 * Makefiles which have recipes but no dependencies (and thus are always
822 considered out of date and in need of remaking), will not be remade (if they
823 were being remade only because they were makefiles). This means that GNU
824 Make will no longer go into an infinite loop when fed the makefiles that
825 `imake' (necessary to build X Windows) produces.
827 * There is no longer a warning for using the `vpath' directive with an explicit
828 pathname (instead of a `%' pattern).
832 * When removing intermediate files, only one `rm' command line is printed,
833 listing all file names.
835 * There are now automatic variables `$(^D)', `$(^F)', `$(?D)', and `$(?F)'.
836 These are the directory-only and file-only versions of `$^' and `$?'.
838 * Library dependencies given as `-lNAME' will use "libNAME.a" in the current
839 directory if it exists.
841 * The automatic variable `$($/)' is no longer defined.
843 * Leading `+' characters on a recipe line make that line be executed even
844 under -n, -t, or -q (as if the line contained `$(MAKE)').
846 * For recipe lines containing `$(MAKE)', `${MAKE}', or leading `+' characters,
847 only those lines are executed, not the entire recipe.
848 (This is how Unix make behaves for lines containing `$(MAKE)' or `${MAKE}'.)
852 * Filenames in rules will now have ~ and ~USER expanded.
854 * The `-p' output has been changed so it can be used as a makefile.
855 (All information that isn't specified by makefiles is prefaced with comment
860 * The % character can be quoted with backslash in implicit pattern rules,
861 static pattern rules, `vpath' directives, and `patsubst', `filter', and
862 `filter-out' functions. A warning is issued if a `vpath' directive's
863 pattern contains no %.
865 * The `wildcard' variable expansion function now expands ~ and ~USER.
867 * Messages indicating failed recipe lines now contain the target name:
868 make: *** [target] Error 1
870 * The `-p' output format has been changed somewhat to look more like
871 makefile rules and to give all information that Make has about files.
877 * The `-l' switch with no argument removes any previous load-average limit.
879 * When the `-w' switch is in effect, and Make has updated makefiles,
880 it will write a `Leaving directory' message before re-executing itself.
881 This makes the `directory change tracking' changes to Emacs's compilation
882 commands work properly.
886 * The automatic variable `$*' is now defined for explicit rules,
887 as it is in Unix make.
891 * The `-j' switch is now put in the MAKEFLAGS and MFLAGS variables when
892 specified without an argument (indicating infinite jobs).
893 The `-l' switch is not always put in the MAKEFLAGS and MFLAGS variables.
895 * Make no longer checks hashed directories after running recipes.
896 The behavior implemented in 3.41 caused too much slowdown.
900 * A dependency is NOT considered newer than its dependent if
901 they have the same modification time. The behavior implemented
902 in 3.43 conflicts with RCS.
906 * Dependency loops are no longer fatal errors.
908 * A dependency is considered newer than its dependent if
909 they have the same modification time.
913 * The variables F77 and F77FLAGS are now set by default to $(FC) and
914 $(FFLAGS). Makefiles designed for System V make may use these variables in
915 explicit rules and expect them to be set. Unfortunately, there is no way to
916 make setting these affect the Fortran implicit rules unless FC and FFLAGS
917 are not used (and these are used by BSD make).
921 * Make now checks to see if its hashed directories are changed by recipes.
922 Other makes that hash directories (Sun, 4.3 BSD) don't do this.
926 * The `shell' function no longer captures standard error output.
930 * A file beginning with a dot can be the default target if it also contains
931 a slash (e.g., `../bin/foo'). (Unix make allows this as well.)
935 * Archive member names are truncated to 15 characters.
937 * Yet more USG stuff.
939 * Minimal support for Microport System V (a 16-bit machine and a
940 brain-damaged compiler). This has even lower priority than other USG
941 support, so if it gets beyond trivial, I will take it out completely.
943 * Revamped default implicit rules (not much visible change).
945 * The -d and -p options can come from the environment.
949 * Improved support for USG and HPUX (hopefully).
951 * A variable reference like `$(foo:a=b)', if `a' contains a `%', is
952 equivalent to `$(patsubst a,b,$(foo))'.
954 * Defining .DEFAULT with no deps or recipe clears its recipe.
956 * New default implicit rules for .S (cpp, then as), and .sh (copy and
957 make executable). All default implicit rules that use cpp (even
958 indirectly), use $(CPPFLAGS).
962 * Giving the -j option with no arguments gives you infinite jobs.
966 * New option: "-l LOAD" says not to start any new jobs while others are
967 running if the load average is not below LOAD (a floating-point number).
969 * There is support in place for implementations of remote command execution
970 in Make. See the file remote.c.
974 * No more than 10 directories will be kept open at once.
975 (This number can be changed by redefining MAX_OPEN_DIRECTORIES in dir.c.)
979 * Archive files will have their modification times recorded before doing
980 anything that might change their modification times by updating an archive
985 * The `MAKELEVEL' variable is defined for use by makefiles.
989 * The recursion level indications in error messages are much shorter than
990 they were in version 3.14.
994 * Leading spaces before directives are ignored (as documented).
996 * Included makefiles can determine the default goal target.
997 (System V Make does it this way, so we are being compatible).
1001 * Variables that are defaults built into Make will not be put in the
1002 environment for children. This just saves some environment space and,
1003 except under -e, will be transparent to sub-makes.
1005 * Error messages from sub-makes will indicate the level of recursion.
1007 * Hopefully some speed-up for large directories due to a change in the
1008 directory hashing scheme.
1010 * One child will always get a standard input that is usable.
1012 * Default makefiles that don't exist will be remade and read in.
1016 * Count parentheses inside expansion function calls so you can
1017 have nested calls: `$(sort $(foreach x,a b,$(x)))'.
1021 * Several bug fixes, including USG and Sun386i support.
1023 * `shell' function to expand shell commands a la `
1025 * If the `-d' flag is given, version information will be printed.
1027 * The `-c' option has been renamed to `-C' for compatibility with tar.
1029 * The `-p' option no longer inhibits other normal operation.
1031 * Makefiles will be updated and re-read if necessary.
1033 * Can now run several recipes at once (parallelism), -j option.
1035 * Error messages will contain the level of Make recursion, if any.
1037 * The `MAKEFLAGS' and `MFLAGS' variables will be scanned for options after
1040 * A double-colon rule with no dependencies will always have its recipe run.
1041 (This is how both the BSD and System V versions of Make do it.)
1045 (Changes from versions 1 through 3.05 were never recorded. Sorry.)
1047 -------------------------------------------------------------------------------
1048 Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
1049 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free
1050 Software Foundation, Inc. This file is part of GNU Make.
1052 GNU Make is free software; you can redistribute it and/or modify it under the
1053 terms of the GNU General Public License as published by the Free Software
1054 Foundation; either version 3 of the License, or (at your option) any later
1057 GNU Make is distributed in the hope that it will be useful, but WITHOUT ANY
1058 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
1059 A PARTICULAR PURPOSE. See the GNU General Public License for more details.
1061 You should have received a copy of the GNU General Public License along with
1062 this program. If not, see <http://www.gnu.org/licenses/>.