This file (NEWS-2.0) lists several incompatibilities planned for a future Automake 2.0 release. However, the (few) current Automake maintainers have insufficient interest and energy to pursue the 2.0 release. We have not even reviewed all existing bugs. New maintainers are needed! For more information about helping with Automake development: https://lists.gnu.org/archive/html/automake/2021-03/msg00018.html Therefore, there is no ETA for Automake 2.0, but it is not likely to be any time soon. So moving these future issues to a separate file seemed warranted. For more info, see the ./PLANS/ directory. * WARNING: Future backward-incompatibilities! - Makefile recipes generated by Automake 2.0 will expect to use an 'rm' program that doesn't complain when called without any non-option argument if the '-f' option is given (so that commands like "rm -f" and "rm -rf" will act as a no-op, instead of raising usage errors). This behavior of 'rm' is very widespread in the wild, and it will be required in the next POSIX version: Accordingly, AM_INIT_AUTOMAKE now expands some shell code that checks that the default 'rm' program in PATH satisfies this requirement, aborting the configure process if this is not the case. For the moment, it's still possible to force the configuration process to succeed even with a broken 'rm', but that will no longer be the case for Automake 2.0. - Automake 2.0 will require Autoconf 2.71 or later. Exact dependencies are unknowable at ths time. - Automake 2.0 will drop support for the long-deprecated 'configure.in' name for the Autoconf input file. You are advised to start using the recommended name 'configure.ac' instead, ASAP. - The ACLOCAL_AMFLAGS special make variable will be fully deprecated in Automake 2.0: it will raise warnings in the "obsolete" category (but still no hard error of course, for compatibilities with the many, many packages that still relies on that variable). You are advised to start relying on the new Automake support for AC_CONFIG_MACRO_DIRS instead (which was introduced in Automake 1.13). - Automake 2.0 will remove support for automatic dependency tracking with the SGI C/C++ compilers on IRIX. The SGI depmode has been reported broken "in the wild" already, and we don't think investing time in debugging and fixing is worthwhile, especially considering that SGI has last updated those compilers in 2006, and retired support for them in December 2013: - Automake 2.0 will remove support for MS-DOS and Windows 95/98/ME (support for them was offered by relying on the DJGPP project). Note however that both Cygwin and MSYS/MinGW on modern Windows versions will continue to be fully supported. - Automake-provided scripts and makefile recipes might (finally!) start assuming a POSIX shell in Automake 2.0. There still is no certainty about this though: we'd first like to wait and see whether future Autoconf versions will be enhanced to guarantee that such a shell is always found and provided by the checks in ./configure. In 2020, config.guess was changed by its then-maintainer to require $(...); the ensuing bug reports and maintenance hassle (unfortunately the changes have not been reverted) are a convincing argument that we should not require a POSIX shell until Solaris 10, at least, is completely gone from the world. - Starting from Automake 2.0, third-party m4 files located in the system-wide aclocal directory, as well as in any directory listed in the ACLOCAL_PATH environment variable, will take precedence over "built-in" Automake macros. For example (assuming Automake is installed in the /usr/local hierarchy), a definition of the AM_PROG_VALAC macro found in '/usr/local/share/aclocal/my-vala.m4' should take precedence over the same-named automake-provided macro (defined in '/usr/local/share/aclocal-2.0/vala.m4'). ----- Copyright (C) 1995-2021 Free Software Foundation, Inc. This program 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. This program 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 this program. If not, see .