GNU make NEWS -*-indented-text-*- History of user-visible changes. 1 April 2006 See the end of this file for copyrights and conditions. All changes mentioned here are more fully described in the GNU make manual, which is contained in this distribution as the file doc/make.texi. See the README file and the GNU make manual for instructions for reporting bugs. Version 3.81 * GNU make is ported to OS/2. * GNU make is ported to MinGW. The MinGW build is only supported by the build_w32.bat batch file; see the file README.W32 for more details. * WARNING: Future backward-incompatibility! Up to and including this release, the '$?' variable does not contain any prerequisite that does not exist, even though that prerequisite might have caused the target to rebuild. Starting with the _next_ release of GNU make, '$?' will contain all prerequisites that caused the target to be considered out of date. See this Savannah bug: http://savannah.gnu.org/bugs/index.php?func=detailitem&item_id=16051 * WARNING: Backward-incompatibility! GNU make now implements a generic "second expansion" feature on the prerequisites of both explicit and implicit (pattern) rules. In order to enable this feature, the special target '.SECONDEXPANSION' must be defined before the first target which takes advantage of it. If this feature is enabled then after all rules have been parsed the prerequisites are expanded again, this time with all the automatic variables in scope. This means that in addition to using standard SysV $$@ in prerequisites lists, you can also use complex functions such as $$(notdir $$@) etc. This behavior applies to implicit rules, as well, where the second expansion occurs when the rule is matched. However, this means that when '.SECONDEXPANSION' is enabled you must double-quote any "$" in your filenames; instead of "foo: boo$$bar" you now must write "foo: foo$$$$bar". Note that the SysV $$@ etc. feature, which used to be available by default, is now ONLY available when the .SECONDEXPANSION target is defined. If your makefiles take advantage of this SysV feature you will need to update them. * WARNING: Backward-incompatibility! In order to comply with POSIX, the way in which GNU make processes backslash-newline sequences in command strings has changed. If your makefiles use backslash-newline sequences inside of single-quoted strings in command scripts you will be impacted by this change. See the GNU make manual subsection "Splitting Command Lines" (node "Splitting Lines"), in section "Command Syntax", chapter "Writing the Commands in Rules", for details. * WARNING: Backward-incompatibility! Some previous versions of GNU make had a bug where "#" in a function invocation such as $(shell ...) was treated as a make comment. A workaround was to escape these with backslashes. This bug has been fixed: if your makefile uses "\#" in a function invocation the backslash is now preserved, so you'll need to remove it. * New command-line option: -L (--check-symlink-times). On systems that support symbolic links, if this option is given then GNU make will use the most recent modification time of any symbolic links that are used to resolve target files. The default behavior remains as it always has: use the modification time of the actual target file only. * The "else" conditional line can now be followed by any other valid conditional on the same line: this does not increase the depth of the conditional nesting, so only one "endif" is required to close the conditional. * All pattern-specific variables that match a given target are now used (previously only the first match was used). * Target-specific variables can be marked as exportable using the "export" keyword. * In a recursive $(call ...) context, any extra arguments from the outer call are now masked in the context of the inner call. * Implemented a solution for the "thundering herd" problem with "-j -l". This version of GNU make uses an algorithm suggested by Thomas Riedl to track the number of jobs started in the last second and artificially adjust GNU make's view of the system's load average accordingly. * New special variables available in this release: - .INCLUDE_DIRS: Expands to a list of directories that make searches for included makefiles. - .FEATURES: Contains a list of special features available in this version of GNU make. - .DEFAULT_GOAL: Set the name of the default goal make will use if no goals are provided on the command line. - MAKE_RESTARTS: If set, then this is the number of times this instance of make has been restarted (see "How Makefiles Are Remade" in the manual). - New automatic variable: $| (added in 3.80, actually): contains all the order-only prerequisites defined for the target. * New functions available in this release: - $(lastword ...) returns the last word in the list. This gives identical results as $(word $(words ...) ...), but is much faster. - $(abspath ...) returns the absolute path (all "." and ".." directories resolved, and any duplicate "/" characters removed) for each path provided. - $(realpath ...) returns the canonical pathname for each path provided. The canonical pathname is the absolute pathname, with all symbolic links resolved as well. - $(info ...) prints its arguments to stdout. No makefile name or line number info, etc. is printed. - $(flavor ...) returns the flavor of a variable. - $(or ...) provides a short-circuiting OR conditional: each argument is expanded. The first true (non-empty) argument is returned; no further arguments are expanded. Expands to empty if there are no true arguments. - $(and ...) provides a short-circuiting AND conditional: each argument is expanded. The first false (empty) argument is returned; no further arguments are expanded. Expands to the last argument if all arguments are true. * Changes made for POSIX compatibility: - Only touch targets (under -t) if they have at least one command. - Setting the SHELL make variable does NOT change the value of the SHELL environment variable given to programs invoked by make. As an enhancement to POSIX, if you export the make variable SHELL then it will be set in the environment, just as before. * On MS Windows systems, explicitly setting SHELL to a pathname ending in "cmd" or "cmd.exe" (case-insensitive) will force GNU make to use the DOS command interpreter in batch mode even if a UNIX-like shell could be found on the system. * On VMS there is now support for case-sensitive filesystems such as ODS5. See the readme.vms file for information. * Parallel builds (-jN) no longer require a working Bourne shell on Windows platforms. They work even with the stock Windows shells, such as cmd.exe and command.com. * Updated to autoconf 2.59, automake 1.9.5, and gettext 0.14.1. Users should not be impacted. * New translations for Swedish, Chinese (simplified), Ukrainian, Belarusian, Finnish, Kinyarwandan, and Irish. Many updated translations. A complete list of bugs fixed in this version is available here: http://savannah.gnu.org/bugs/index.php?group=make&report_id=111&fix_release_id=103 ------------------------------------------------------------------------------- Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. This file is part of GNU Make. GNU Make is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Make is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Make; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.