1 GNU make NEWS -*-indented-text-*-
2 History of user-visible changes.
5 Copyright (C) 2002,2003,2004,2005 Free Software Foundation, Inc.
6 See the end for copying conditions.
8 All changes mentioned here are more fully described in the GNU make
9 manual, which is contained in this distribution as the file doc/make.texi.
10 See the README file and the GNU make manual for instructions for
15 * GNU make is ported to OS/2.
17 * GNU make is ported to MinGW.
19 * WARNING: Backward-incompatibility!
20 GNU make now implements a generic "second expansion" feature on the
21 prerequisites of both explicit and implicit (pattern) targets. After
22 the rule has been parsed, the prerequisites are expanded a second
23 time, this time with all the automatic variables in scope. This means
24 that in addition to using standard SysV $$@ in prerequisites lists,
25 you can also use complex functions such as $$(patsubst f%r,b%o,$$@) etc.
26 This behavior applies to implicit rules, as well, where the second
27 expansion occurs after the rule is matched.
28 However, this means that you need to double-quote any "$" in your
29 filenames; instead of "foo: boo$$bar" you must write "foo: foo$$$$bar"
31 * New command-line option: -L (--check-symlink-times). On systems that
32 support symbolic links, if this option is given then GNU make will
33 use the most recent modification time of any symbolic links that are
34 used to resolve target files. The default behavior remains as it
35 always has: use the modification time of the actual target file only.
37 * All pattern-specific variables that match a given target are now used
38 (previously only the first match was used).
40 * Target-specific variables can be marked as exportable using the
43 * In a recursive $(call ...) context, any extra arguments from the outer
44 call are now masked in the context of the inner call.
46 * Implemented a solution for the "thundering herd" problem with "-j -l".
47 This version of GNU make uses an algorithm suggested by Thomas Riedl
48 <thomas.riedl@siemens.com> to track the number of jobs started in the
49 last second and artificially adjust GNU make's view of the system's
50 load average accordingly.
52 * New special variables available in this release:
53 - .DEFAULT_TARGET: Contains the name of the default target make will
54 use if no targets are provided on the command line. It can be set
55 to change the default target.
56 - New automatic variable: $| (added in 3.80, actually): contains all
57 the order-only prerequisites defined for the target.
59 * New functions available in this release:
60 - $(lastword ...) returns the last word in the list. This gives
61 identical results as $(word $(words ...) ...), but is much faster.
62 - $(abspath ...) returns the absolute path (all "." and ".."
63 directories resolved, and any duplicate "/" characters removed) for
65 - $(realpath ...) returns the canonical pathname for each path
66 provided. The canonical pathname is the absolute pathname, with
67 all symbolic links resolved as well.
68 - $(info ...) prints informative messages to stdout. No makefile
69 name or line number info, etc. is printed, just the message.
71 * Changes made for POSIX compatibility:
72 - Only touch targets (under -t) if they have at least one command.
73 - Setting the SHELL make variable does NOT change the value of the
74 SHELL environment variable given to programs invoked by make. As
75 an enhancement to POSIX, if you export the make variable SHELL then
76 it will be set in the environment, just as before.
78 * On DOS and MS Windows systems, explicitly setting SHELL to a pathname
79 ending in "cmd" or "cmd.exe" (case-insensitive) will force GNU make to
80 use the DOS command interpreter in batch mode even if a UNIX-like
81 shell could be found on the system.
83 * Updated to autoconf 2.59, automake 1.8.2, and gettext 0.14.1. Users
84 should not be impacted.
86 * New translations for Swedish, Chinese (simplified), Ukrainian,
87 Belarusian, Finnish, and Irish. Many updated translations.
92 * A new feature exists: order-only prerequisites. These prerequisites
93 affect the order in which targets are built, but they do not impact
94 the rebuild/no-rebuild decision of their dependents. That is to say,
95 they allow you to require target B be built before target A, without
96 requiring that target A will always be rebuilt if target B is updated.
97 Patch for this feature provided by Greg McGary <greg@mcgary.org>.
99 * For compatibility with SysV make, GNU make now supports the peculiar
100 syntax $$@, $$(@D), and $$(@F) in the prerequisites list of a rule.
101 This syntax is only valid within explicit and static pattern rules: it
102 cannot be used in implicit (suffix or pattern) rules. Edouard G. Parmelan
103 <egp@free.fr> provided a patch implementing this feature; however, I
104 decided to implement it in a different way.
106 * The argument to the "ifdef" conditional is now expanded before it's
107 tested, so it can be a constructed variable name.
109 Similarly, the arguments to "export" (when not used in a variable
110 definition context) and "unexport" are also now expanded.
112 * A new function is defined: $(value ...). The argument to this
113 function is the _name_ of a variable. The result of the function is
114 the value of the variable, without having been expanded.
116 * A new function is defined: $(eval ...). The arguments to this
117 function should expand to makefile commands, which will then be
118 evaluated as if they had appeared in the makefile. In combination
119 with define/endef multiline variable definitions this is an extremely
120 powerful capability. The $(value ...) function is also sometimes
123 * A new built-in variable is defined, $(MAKEFILE_LIST). It contains a
124 list of each makefile GNU make has read, or started to read, in the
125 order in which they were encountered. So, the last filename in the
126 list when a makefile is just being read (before any includes) is the
127 name of the current makefile.
129 * A new built-in variable is defined: $(.VARIABLES). When it is
130 expanded it returns a complete list of variable names defined by all
131 makefiles at that moment.
133 * A new command-line option is defined, -B or --always-make. If
134 specified GNU make will consider all targets out-of-date even if they
135 would otherwise not be.
137 * The arguments to $(call ...) functions were being stored in $1, $2,
138 etc. as recursive variables, even though they are fully expanded
139 before assignment. This means that escaped dollar signs ($$ etc.)
140 were not behaving properly. Now the arguments are stored as simple
141 variables. This may mean that if you added extra escaping to your
142 $(call ...) function arguments you will need to undo it now.
144 * The variable invoked by $(call ...) can now be recursive: unlike other
145 variables it can reference itself and this will not produce an error
146 when it is used as the first argument to $(call ...) (but only then).
148 * New pseudo-target .LOW_RESOLUTION_TIME, superseding the configure
149 option --disable-nsec-timestamps. You might need this if your build
150 process depends on tools like "cp -p" preserving time stamps, since
151 "cp -p" (right now) doesn't preserve the subsecond portion of a time
154 * Updated translations for French, Galician, German, Japanese, Korean,
155 and Russian. New translations for Croatian, Danish, Hebrew, and
158 * Updated internationalization support to Gettext 0.11.5.
159 GNU make now uses Gettext's "external" feature, and does not include
160 any internationalization code itself. Configure will search your
161 system for an existing implementation of GNU Gettext (only GNU Gettext
162 is acceptable) and use it if it exists. If not, NLS will be disabled.
163 See ABOUT-NLS for more information.
165 * Updated to autoconf 2.54 and automake 1.7. Users should not be impacted.
169 * .SECONDARY with no prerequisites now prevents any target from being
170 removed because make thinks it's an intermediate file, not just those
171 listed in the makefile.
173 * New configure option --disable-nsec-timestamps, but this was
174 superseded in later versions by the .LOW_RESOLUTION_TIME pseudo-target.
178 * GNU make optionally supports internationalization and locales via the
179 GNU gettext (or local gettext if suitable) package. See the ABOUT-NLS
180 file for more information on configuring GNU make for NLS.
182 * Previously, GNU make quoted variables such as MAKEFLAGS and
183 MAKEOVERRIDES for proper parsing by the shell. This allowed them to
184 be used within make build scripts. However, using them there is not
185 proper behavior: they are meant to be passed to subshells via the
186 environment. Unfortunately the values were not quoted properly to be
187 passed through the environment. This meant that make didn't properly
188 pass some types of command line values to submakes.
190 With this version we change that behavior: now these variables are
191 quoted properly for passing through the environment, which is the
192 correct way to do it. If you previously used these variables
193 explicitly within a make rule you may need to re-examine your use for
194 correctness given this change.
196 * A new pseudo-target .NOTPARALLEL is available. If defined, the
197 current makefile is run serially regardless of the value of -j.
198 However, submakes are still eligible for parallel execution.
200 * The --debug option has changed: it now allows optional flags
201 controlling the amount and type of debugging output. By default only
202 a minimal amount information is generated, displaying the names of
203 "normal" targets (not makefiles) that were deemed out of date and in
204 need of being rebuilt.
206 Note that the -d option behaves as before: it takes no arguments and
207 all debugging information is generated.
209 * The `-p' (print database) output now includes filename and linenumber
210 information for variable definitions, to aid debugging.
212 * The wordlist function no longer reverses its arguments if the "start"
213 value is greater than the "end" value. If that's true, nothing is
216 * Hartmut Becker provided many updates for the VMS port of GNU make.
217 See the readme.vms file for more details.
221 * Two new functions, $(error ...) and $(warning ...) are available. The
222 former will cause make to fail and exit immediately upon expansion of
223 the function, with the text provided as the error message. The latter
224 causes the text provided to be printed as a warning message, but make
227 * A new function $(call ...) is available. This allows users to create
228 their own parameterized macros and invoke them later. Original
229 implementation of this function was provided by Han-Wen Nienhuys
232 * A new function $(if ...) is available. It provides if-then-else
233 capabilities in a builtin function. Original implementation of this
234 function was provided by Han-Wen Nienhuys <hanwen@cs.uu.nl>.
236 * Make defines a new variable, .LIBPATTERNS. This variable controls how
237 library dependency expansion (dependencies like ``-lfoo'') is performed.
239 * Make accepts CRLF sequences as well as traditional LF, for
240 compatibility with makefiles created on other operating systems.
242 * Make accepts a new option: -R, or --no-builtin-variables. This option
243 disables the definition of the rule-specific builtin variables (CC,
244 LD, AR, etc.). Specifying this option forces -r (--no-builtin-rules)
247 * A "job server" feature, suggested by Howard Chu <hyc@highlandsun.com>.
249 On systems that support POSIX pipe(2) semantics, GNU make can now pass
250 -jN options to submakes rather than forcing them all to use -j1. The
251 top make and all its sub-make processes use a pipe to communicate with
252 each other to ensure that no more than N jobs are started across all
253 makes. To get the old behavior of -j back, you can configure make
254 with the --disable-job-server option.
256 * The confusing term "dependency" has been replaced by the more accurate
257 and standard term "prerequisite", both in the manual and in all GNU make
260 * GNU make supports the "big archive" library format introduced in AIX 4.3.
262 * GNU make supports large files on AIX, HP-UX, and IRIX. These changes
263 were provided by Paul Eggert <eggert@twinsun.com>. (Large file
264 support for Solaris and Linux was introduced in 3.77, but the
265 configuration had issues: these have also been resolved).
267 * The Windows 95/98/NT (W32) version of GNU make now has native support
268 for the Cygnus Cygwin release B20.1 shell (bash).
270 * The GNU make regression test suite, long available separately "under
271 the table", has been integrated into the release. You can invoke it
272 by running "make check" in the distribution. Note that it requires
273 Perl (either Perl 4 or Perl 5) to run.
277 * Implement BSD make's "?=" variable assignment operator. The variable
278 is assigned the specified value only if that variable is not already
281 * Make defines a new variable, "CURDIR", to contain the current working
282 directory (after the -C option, if any, has been processed).
283 Modifying this variable has no effect on the operation of make.
285 * Make defines a new default RCS rule, for new-style master file
286 storage: ``% :: RCS/%'' (note no ``,v'' suffix).
288 Make defines new default rules for DOS-style C++ file naming
289 conventions, with ``.cpp'' suffixes. All the same rules as for
290 ``.cc'' and ``.C'' suffixes are provided, along with LINK.cpp and
291 COMPILE.cpp macros (which default to the same value as LINK.cc and
292 COMPILE.cc). Note CPPFLAGS is still C preprocessor flags! You should
293 use CXXFLAGS to change C++ compiler flags.
295 * A new feature, "target-specific variable values", has been added.
296 This is a large change so please see the appropriate sections of the
297 manual for full details. Briefly, syntax like this:
299 TARGET: VARIABLE = VALUE
301 defines VARIABLE as VALUE within the context of TARGET. This is
302 similar to SunOS make's "TARGET := VARIABLE = VALUE" feature. Note
303 that the assignment may be of any type, not just recursive, and that
304 the override keyword is available.
306 COMPATIBILITY: This new syntax means that if you have any rules where
307 the first or second dependency has an equal sign (=) in its name,
308 you'll have to escape them with a backslash: "foo : bar\=baz".
309 Further, if you have any dependencies which already contain "\=",
310 you'll have to escape both of them: "foo : bar\\\=baz".
312 * A new appendix listing the most common error and warning messages
313 generated by GNU make, with some explanation, has been added to the
314 GNU make User's Manual.
316 * Updates to the GNU make Customs library support (see README.customs).
318 * Updates to the Windows 95/NT port from Rob Tulloh (see README.W32),
319 and to the DOS port from Eli Zaretski (see README.DOS).
323 * Small (but serious) bug fix. Quick rollout to get into the GNU source CD.
327 * GNU make now uses automake to control Makefile.in generation. This
328 should make it more consistent with the GNU standards.
330 * VPATH functionality has been changed to incorporate the VPATH+ patch,
331 previously maintained by Paul Smith <psmith@baynetworks.com>. See the
334 * Make defines a new variable, `MAKECMDGOALS', to contain the goals that
335 were specified on the command line, if any. Modifying this variable
336 has no effect on the operation of make.
338 * A new function, `$(wordlist S,E,TEXT)', is available: it returns a
339 list of words from number S to number E (inclusive) of TEXT.
341 * Instead of an error, detection of future modification times gives a
342 warning and continues. The warning is repeated just before GNU make
343 exits, so it is less likely to be lost.
345 * Fix the $(basename) and $(suffix) functions so they only operate on
346 the last filename, not the entire string:
348 Command Old Result New Result
349 ------- ---------- ----------
351 $(basename a.b/c) a a.b/c
353 $(suffix a.b/c) b/c <empty>
355 * The $(strip) function now removes newlines as well as TABs and spaces.
357 * The $(shell) function now changes CRLF (\r\n) pairs to a space as well
360 * Updates to the Windows 95/NT port from Rob Tulloh (see README.W32).
362 * Eli Zaretskii has updated the port to 32-bit protected mode on MSDOS
363 and MS-Windows, building with the DJGPP v2 port of GNU C/C++ compiler
364 and utilities. See README.DOS for details, and direct all questions
365 concerning this port to Eli Zaretskii <eliz@is.elta.co.il> or DJ
366 Delorie <dj@delorie.com>.
368 * John W. Eaton has updated the VMS port to support libraries and VPATH.
372 * The directory messages printed by `-w' and implicitly in sub-makes,
373 are now omitted if Make runs no commands and has no other messages to print.
375 * Make now detects files that for whatever reason have modification times
376 in the future and gives an error. Files with such impossible timestamps
377 can result from unsynchronized clocks, or archived distributions
378 containing bogus timestamps; they confuse Make's dependency engine
381 * The new directive `sinclude' is now recognized as another name for
382 `-include', for compatibility with some other Makes.
384 * Aaron Digulla has contributed a port to AmigaDOS. See README.Amiga for
385 details, and direct all Amiga-related questions to <digulla@fh-konstanz.de>.
387 * Rob Tulloh of Tivoli Systems has contributed a port to Windows NT or 95.
388 See README.W32 for details, and direct all Windows-related questions to
389 <rob_tulloh@tivoli.com>.
393 * Converted to use Autoconf version 2, so `configure' has some new options.
394 See INSTALL for details.
396 * You can now send a SIGUSR1 signal to Make to toggle printing of debugging
397 output enabled by -d, at any time during the run.
401 * DJ Delorie has ported Make to MS-DOS using the GO32 extender.
402 He is maintaining the DOS port, not the GNU Make maintainer;
403 please direct bugs and questions for DOS to <djgpp@sun.soe.clarkson.edu>.
404 MS-DOS binaries are available for FTP from ftp.simtel.net in
405 /pub/simtelnet/gnu/djgpp/.
407 * The `MAKEFLAGS' variable (in the environment or in a makefile) can now
408 contain variable definitions itself; these are treated just like
409 command-line variable definitions. Make will automatically insert any
410 variable definitions from the environment value of `MAKEFLAGS' or from
411 the command line, into the `MAKEFLAGS' value exported to children. The
412 `MAKEOVERRIDES' variable previously included in the value of `$(MAKE)'
413 for sub-makes is now included in `MAKEFLAGS' instead. As before, you can
414 reset `MAKEOVERRIDES' in your makefile to avoid putting all the variables
415 in the environment when its size is limited.
417 * If `.DELETE_ON_ERROR' appears as a target, Make will delete the target of
418 a rule if it has changed when its commands exit with a nonzero status,
419 just as when the commands get a signal.
421 * The automatic variable `$+' is new. It lists all the dependencies like
422 `$^', but preserves duplicates listed in the makefile. This is useful
423 for linking rules, where library files sometimes need to be listed twice
426 * You can now specify the `.IGNORE' and `.SILENT' special targets with
427 dependencies to limit their effects to those files. If a file appears as
428 a dependency of `.IGNORE', then errors will be ignored while running the
429 commands to update that file. Likewise if a file appears as a dependency
430 of `.SILENT', then the commands to update that file will not be printed
431 before they are run. (This change was made to conform to POSIX.2.)
435 * The automatic variables `$(@D)', `$(%D)', `$(*D)', `$(<D)', `$(?D)', and
436 `$(^D)' now omit the trailing slash from the directory name. (This change
437 was made to comply with POSIX.2.)
439 * The source distribution now includes the Info files for the Make manual.
440 There is no longer a separate distribution containing Info and DVI files.
442 * You can now set the variables `binprefix' and/or `manprefix' in
443 Makefile.in (or on the command line when installing) to install GNU make
444 under a name other than `make' (i.e., ``make binprefix=g install''
445 installs GNU make as `gmake').
447 * The built-in Texinfo rules use the new variables `TEXI2DVI_FLAGS' for
448 flags to the `texi2dvi' script, and `MAKEINFO_FLAGS' for flags to the
451 * The exit status of Make when it runs into errors is now 2 instead of 1.
452 The exit status is 1 only when using -q and some target is not up to date.
453 (This change was made to comply with POSIX.2.)
457 * It is no longer a fatal error to have a NUL character in a makefile.
458 You should never put a NUL in a makefile because it can have strange
459 results, but otherwise empty lines full of NULs (such as produced by
460 the `xmkmf' program) will always work fine.
462 * The error messages for nonexistent included makefiles now refer to the
463 makefile name and line number where the `include' appeared, so Emacs's
464 C-x ` command takes you there (in case it's a typo you need to fix).
468 * Implicit rule search for archive member references is now done in the
469 opposite order from previous versions: the whole target name `LIB(MEM)'
470 first, and just the member name and parentheses `(MEM)' second.
472 * Make now gives an error for an unterminated variable or function reference.
473 For example, `$(foo' with no matching `)' or `${bar' with no matching `}'.
475 * The new default variable `MAKE_VERSION' gives the version number of
476 Make, and a string describing the remote job support compiled in (if any).
477 Thus the value (in this release) is something like `3.69' or `3.69-Customs'.
479 * Commands in an invocation of the `shell' function are no longer run with
480 a modified environment like target commands are. As in versions before
481 3.68, they now run with the environment that `make' started with. We
482 have reversed the change made in version 3.68 because it turned out to
483 cause a paradoxical situation in cases like:
485 export variable = $(shell echo value)
487 When Make attempted to put this variable in the environment for a target
488 command, it would try expand the value by running the shell command
489 `echo value'. In version 3.68, because it constructed an environment
490 for that shell command in the same way, Make would begin to go into an
491 infinite loop and then get a fatal error when it detected the loop.
493 * The commands given for `.DEFAULT' are now used for phony targets with no
498 * You can list several archive member names inside parenthesis:
499 `lib(mem1 mem2 mem3)' is equivalent to `lib(mem1) lib(mem2) lib(mem3)'.
501 * You can use wildcards inside archive member references. For example,
502 `lib(*.o)' expands to all existing members of `lib' whose names end in
503 `.o' (e.g. `lib(a.o) lib(b.o)'); `*.a(*.o)' expands to all such members
504 of all existing files whose names end in `.a' (e.g. `foo.a(a.o)
505 foo.a(b.o) bar.a(c.o) bar.a(d.o)'.
507 * A suffix rule `.X.a' now produces two pattern rules:
508 (%.o): %.X # Previous versions produced only this.
509 %.a: %.X # Now produces this as well, just like other suffixes.
511 * The new flag `--warn-undefined-variables' says to issue a warning message
512 whenever Make expands a reference to an undefined variable.
514 * The new `-include' directive is just like `include' except that there is
515 no error (not even a warning) for a nonexistent makefile.
517 * Commands in an invocation of the `shell' function are now run with a
518 modified environment like target commands are, so you can use `export' et
519 al to set up variables for them. They used to run with the environment
520 that `make' started with.
524 * `make --version' (or `make -v') now exits immediately after printing
529 * Make now supports long-named members in `ar' archive files.
533 * Make now supports the `+=' syntax for a variable definition which appends
534 to the variable's previous value. See the section `Appending More Text
535 to Variables' in the manual for full details.
537 * The new option `--no-print-directory' inhibits the `-w' or
538 `--print-directory' feature. Make turns on `--print-directory'
539 automatically if you use `-C' or `--directory', and in sub-makes; some
540 users have found this behavior undesirable.
542 * The built-in implicit rules now support the alternative extension
543 `.txinfo' for Texinfo files, just like `.texinfo' and `.texi'.
547 * Make now uses a standard GNU `configure' script. See the new file
548 INSTALL for the new (and much simpler) installation procedure.
550 * There is now a shell script to build Make the first time, if you have no
551 other `make' program. `build.sh' is created by `configure'; see README.
553 * GNU Make now completely conforms to the POSIX.2 specification for `make'.
555 * Elements of the `$^' and `$?' automatic variables that are archive
556 member references now list only the member name, as in Unix and POSIX.2.
558 * You should no longer ever need to specify the `-w' switch, which prints
559 the current directory before and after Make runs. The `-C' switch to
560 change directory, and recursive use of Make, now set `-w' automatically.
562 * Multiple double-colon rules for the same target will no longer have their
563 commands run simultaneously under -j, as this could result in the two
564 commands trying to change the file at the same time and interfering with
567 * The `SHELL' variable is now never taken from the environment.
568 Each makefile that wants a shell other than the default (/bin/sh) must
569 set SHELL itself. SHELL is always exported to child processes.
570 This change was made for compatibility with POSIX.2.
572 * Make now accepts long options. There is now an informative usage message
573 that tells you what all the options are and what they do. Try `make --help'.
575 * There are two new directives: `export' and `unexport'. All variables are
576 no longer automatically put into the environments of the commands that
577 Make runs. Instead, only variables specified on the command line or in
578 the environment are exported by default. To export others, use:
580 or you can define variables with:
581 export VARIABLE = VALUE
583 export VARIABLE := VALUE
587 .EXPORT_ALL_VARIABLES:
588 to get the old behavior. See the node `Variables/Recursion' in the manual
589 for a full description.
591 * The commands from the `.DEFAULT' special target are only applied to
592 targets which have no rules at all, not all targets with no commands.
593 This change was made for compatibility with Unix make.
595 * All fatal error messages now contain `***', so they are easy to find in
598 * Dependency file names like `-lNAME' are now replaced with the actual file
599 name found, as with files found by normal directory search (VPATH).
600 The library file `libNAME.a' may now be found in the current directory,
601 which is checked before VPATH; the standard set of directories (/lib,
602 /usr/lib, /usr/local/lib) is now checked last.
603 See the node `Libraries/Search' in the manual for full details.
605 * A single `include' directive can now specify more than one makefile to
608 You can also use shell file name patterns in an `include' directive:
611 * The default directories to search for included makefiles, and for
612 libraries specified with `-lNAME', are now set by configuration.
614 * You can now use blanks as well as colons to separate the directories in a
615 search path for the `vpath' directive or the `VPATH' variable.
617 * You can now use variables and functions in the left hand side of a
618 variable assignment, as in "$(foo)bar = value".
620 * The `MAKE' variable is always defined as `$(MAKE_COMMAND) $(MAKEOVERRIDES)'.
621 The `MAKE_COMMAND' variable is now defined to the name with which make
624 * The built-in rules for C++ compilation now use the variables `$(CXX)' and
625 `$(CXXFLAGS)' instead of `$(C++)' and `$(C++FLAGS)'. The old names had
626 problems with shells that cannot have `+' in environment variable names.
628 * The value of a recursively expanded variable is now expanded when putting
629 it into the environment for child processes. This change was made for
630 compatibility with Unix make.
632 * A rule with no targets before the `:' is now accepted and ignored.
633 This change was made for compatibility with SunOS 4 make.
634 We do not recommend that you write your makefiles to take advantage of this.
636 * The `-I' switch can now be used in MAKEFLAGS, and are put there
637 automatically just like other switches.
641 * Built-in rules for C++ source files with the `.C' suffix.
642 We still recommend that you use `.cc' instead.
644 * If commands are given too many times for a single target,
645 the last set given is used, and a warning message is printed.
647 * Error messages about makefiles are in standard GNU error format,
648 so C-x ` in Emacs works on them.
650 * Dependencies of pattern rules which contain no % need not actually exist
651 if they can be created (just like dependencies which do have a %).
655 * A message is always printed when Make decides there is nothing to be done.
656 It used to be that no message was printed for top-level phony targets
657 (because "`phony' is up to date" isn't quite right). Now a different
658 message "Nothing to be done for `phony'" is printed in that case.
660 * Archives on AIX now supposedly work.
662 * When the commands specified for .DEFAULT are used to update a target,
663 the $< automatic variable is given the same value as $@ for that target.
664 This is how Unix make behaves, and this behavior is mandated by POSIX.2.
668 * The -n, -q, and -t options are not put in the `MAKEFLAGS' and `MFLAG'
669 variables while remaking makefiles, so recursive makes done while remaking
670 makefiles will behave properly.
672 * If the special target `.NOEXPORT' is specified in a makefile,
673 only variables that came from the environment and variables
674 defined on the command line are exported.
678 * Suffix rules may have dependencies (which are ignored).
682 * Dependencies of the form `-lLIB' are searched for as /usr/local/lib/libLIB.a
683 as well as libLIB.a in /usr/lib, /lib, the current directory, and VPATH.
687 * There is now a Unix man page for GNU Make. It is certainly not a replacement
688 for the Texinfo manual, but it documents the basic functionality and the
689 switches. For full documentation, you should still read the Texinfo manual.
690 Thanks to Dennis Morse of Stanford University for contributing the initial
693 * Variables which are defined by default (e.g., `CC') will no longer be put
694 into the environment for child processes. (If these variables are reset by the
695 environment, makefiles, or the command line, they will still go into the
698 * Makefiles which have commands but no dependencies (and thus are always
699 considered out of date and in need of remaking), will not be remade (if they
700 were being remade only because they were makefiles). This means that GNU
701 Make will no longer go into an infinite loop when fed the makefiles that
702 `imake' (necessary to build X Windows) produces.
704 * There is no longer a warning for using the `vpath' directive with an explicit
705 pathname (instead of a `%' pattern).
709 * When removing intermediate files, only one `rm' command line is printed,
710 listing all file names.
712 * There are now automatic variables `$(^D)', `$(^F)', `$(?D)', and `$(?F)'.
713 These are the directory-only and file-only versions of `$^' and `$?'.
715 * Library dependencies given as `-lNAME' will use "libNAME.a" in the current
716 directory if it exists.
718 * The automatic variable `$($/)' is no longer defined.
720 * Leading `+' characters on a command line make that line be executed even
721 under -n, -t, or -q (as if the line contained `$(MAKE)').
723 * For command lines containing `$(MAKE)', `${MAKE}', or leading `+' characters,
724 only those lines are executed, not their entire rules.
725 (This is how Unix make behaves for lines containing `$(MAKE)' or `${MAKE}'.)
729 * Filenames in rules will now have ~ and ~USER expanded.
731 * The `-p' output has been changed so it can be used as a makefile.
732 (All information that isn't specified by makefiles is prefaced with comment
737 * The % character can be quoted with backslash in implicit pattern rules,
738 static pattern rules, `vpath' directives, and `patsubst', `filter', and
739 `filter-out' functions. A warning is issued if a `vpath' directive's
740 pattern contains no %.
742 * The `wildcard' variable expansion function now expands ~ and ~USER.
744 * Messages indicating failed commands now contain the target name:
745 make: *** [target] Error 1
747 * The `-p' output format has been changed somewhat to look more like
748 makefile rules and to give all information that Make has about files.
754 * The `-l' switch with no argument removes any previous load-average limit.
756 * When the `-w' switch is in effect, and Make has updated makefiles,
757 it will write a `Leaving directory' messagfe before re-executing itself.
758 This makes the `directory change tracking' changes to Emacs's compilation
759 commands work properly.
763 * The automatic variable `$*' is now defined for explicit rules,
764 as it is in Unix make.
768 * The `-j' switch is now put in the MAKEFLAGS and MFLAGS variables when
769 specified without an argument (indicating infinite jobs).
770 The `-l' switch is not always put in the MAKEFLAGS and MFLAGS variables.
772 * Make no longer checks hashed directories after running commands.
773 The behavior implemented in 3.41 caused too much slowdown.
777 * A dependency is NOT considered newer than its dependent if
778 they have the same modification time. The behavior implemented
779 in 3.43 conflicts with RCS.
783 * Dependency loops are no longer fatal errors.
785 * A dependency is considered newer than its dependent if
786 they have the same modification time.
790 * The variables F77 and F77FLAGS are now set by default to $(FC) and
791 $(FFLAGS). Makefiles designed for System V make may use these variables in
792 explicit rules and expect them to be set. Unfortunately, there is no way to
793 make setting these affect the Fortran implicit rules unless FC and FFLAGS
794 are not used (and these are used by BSD make).
798 * Make now checks to see if its hashed directories are changed by commands.
799 Other makes that hash directories (Sun, 4.3 BSD) don't do this.
803 * The `shell' function no longer captures standard error output.
807 * A file beginning with a dot can be the default target if it also contains
808 a slash (e.g., `../bin/foo'). (Unix make allows this as well.)
812 * Archive member names are truncated to 15 characters.
814 * Yet more USG stuff.
816 * Minimal support for Microport System V (a 16-bit machine and a
817 brain-damaged compiler). This has even lower priority than other USG
818 support, so if it gets beyond trivial, I will take it out completely.
820 * Revamped default implicit rules (not much visible change).
822 * The -d and -p options can come from the environment.
826 * Improved support for USG and HPUX (hopefully).
828 * A variable reference like `$(foo:a=b)', if `a' contains a `%', is
829 equivalent to `$(patsubst a,b,$(foo))'.
831 * Defining .DEFAULT with no deps or commands clears its commands.
833 * New default implicit rules for .S (cpp, then as), and .sh (copy and make
834 executable). All default implicit rules that use cpp (even indirectly), use
839 * Giving the -j option with no arguments gives you infinite jobs.
843 * New option: "-l LOAD" says not to start any new jobs while others are
844 running if the load average is not below LOAD (a floating-point number).
846 * There is support in place for implementations of remote command execution
847 in Make. See the file remote.c.
851 * No more than 10 directories will be kept open at once.
852 (This number can be changed by redefining MAX_OPEN_DIRECTORIES in dir.c.)
856 * Archive files will have their modification times recorded before doing
857 anything that might change their modification times by updating an archive
862 * The `MAKELEVEL' variable is defined for use by makefiles.
866 * The recursion level indications in error messages are much shorter than
867 they were in version 3.14.
871 * Leading spaces before directives are ignored (as documented).
873 * Included makefiles can determine the default goal target.
874 (System V Make does it this way, so we are being compatible).
878 * Variables that are defaults built into Make will not be put in the
879 environment for children. This just saves some environment space and,
880 except under -e, will be transparent to sub-makes.
882 * Error messages from sub-makes will indicate the level of recursion.
884 * Hopefully some speed-up for large directories due to a change in the
885 directory hashing scheme.
887 * One child will always get a standard input that is usable.
889 * Default makefiles that don't exist will be remade and read in.
893 * Count parentheses inside expansion function calls so you can
894 have nested calls: `$(sort $(foreach x,a b,$(x)))'.
898 * Several bug fixes, including USG and Sun386i support.
900 * `shell' function to expand shell commands a la `
902 * If the `-d' flag is given, version information will be printed.
904 * The `-c' option has been renamed to `-C' for compatibility with tar.
906 * The `-p' option no longer inhibits other normal operation.
908 * Makefiles will be updated and re-read if necessary.
910 * Can now run several commands at once (parallelism), -j option.
912 * Error messages will contain the level of Make recursion, if any.
914 * The `MAKEFLAGS' and `MFLAGS' variables will be scanned for options after
917 * A double-colon rule with no dependencies will always have its commands run.
918 (This is how both the BSD and System V versions of Make do it.)
922 (Changes from versions 1 through 3.05 were never recorded. Sorry.)
924 ----------------------------------------------------------------------
925 Copyright information:
927 Permission is granted to anyone to make or distribute verbatim copies
928 of this document as received, in any medium, provided that the
929 copyright notice and this permission notice are preserved, thus
930 giving the recipient permission to redistribute in turn.
932 Permission is granted to distribute modified versions of this
933 document, or of portions of it, under the above conditions, provided
934 also that they carry prominent notices stating who last changed them.