As the file comments say, this was a backport of an autoconf-2.60 fix,
and shouldn't matter for >autoconf-2.59 versions. Drop it since we use
and require autoconf-2.69 now.
Currently this is only enabled in the top-level as that's the only
place where it seemed to be used. But the libc/sys/phoenix/ dir
also uses this functionality, but fails to explicitly enable it.
Automake workedaround it, but generated warnings. Move the option
to NEWLIB_CONFIGURE so all dirs get it automatically iff they end
up using the option. If they don't use the option, there's no
difference to the generated code.
Since AM_INIT_AUTOMAKE calls AC_PROG_AWK, and some configure.ac
scripts call it too, we end up testing for awk multiple times. If
we change NEWLIB_CONFIGURE to require the macro instead, then it
makes sure it's always expanded, but only once.
While we're here, do the same thing with AC_PROG_INSTALL since it
is also called by AM_INIT_AUTOMAKE, although it doesn't currently
result in duplicate configure checks.
The AC_LIBTOOL_WIN32_DLL macro has been deprecated for a while and code
should call LT_INIT with win32-dll instead. Update the calls to match.
The generated code is noisy not because of substantial differences, but
because the order of some macros change (i.e. instead of calling AS and
then CC, CC is called first and then AS).
Since automake already sets per-library CCASFLAGS to $(AM_CCASFLAGS)
by default, there's no need to explicitly set it here.
Many of these dirs don't have .S files in the first place, so the rule
doesn't even do anything. That can easily be seen when Makefile.in has
no changes as a result.
For the dirs with .S files, the custom rules are the same as the pattern
.S.o rules, so this is a nice cleanup.
The only dir that was adding extra flags (newlib/libc/machine/mn10300/)
to the per-library setting can have it moved to the global AM_CCASFLAGS
since the subdir only has one target. Although the setting just adds
extra debugging flags, so maybe it should be deleted in general.
There are a few dirs that we leave the redundant setting in place. This
is to workaround an automake limitation in subdirs that support building
with & w/out libtool:
https://www.gnu.org/software/automake/manual/html_node/Objects-created-both-with-libtool-and-without.html
When trying to create a directory called `xyz` in the presence of a
directory `xyz.lnk`, the Cygwin runtime errors out with an `ENOENT`.
The root cause is actually a bit deeper: the `symlink_info::check()`
method tries to figure out whether the given path refers to a symbolic
link as emulated via `.lnk` files, but since it is a directory, that is
not the case, and that hypothesis is rejected.
However, the `fileattr` field is not cleared, so that a later
`.exists()` call on the instance mistakenly thinks that the symlink
actually exists. Let's clear that field.
This fixes https://github.com/msys2/msys2-runtime/issues/81
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
AAAA records returned from Windows resolver were flagged as "No
structure" in debug output because of being processed (although
correctly) in the default catch-all case. This patch makes the AAAA
records properly recognized.
Use standard AC_MSG_WARN macro in the top-level configure, and delete
the message from all the subdirs. There's no need to issue this more
than once per libgloss build.
Top level:
Merge from GCC:
PR bootstrap/82856
* multilib.am: New file. From automake.
config:
Merge from GCC:
PR bootstrap/82856
* math.m4, tls.m4: Use AC_LANG_SOURCE.
zlib:
Merge from GCC.
PR bootstrap/82856
* Makefile.am: Include multilib.am.
* Makefile.in: Regenerate.
This matches what the other GNU toolchain projects have done already.
The generated diff in practice isn't terribly large. This will allow
more use of subdir local.mk includes due to fixes & improvements that
came after the 1.11 release series.
The newlib & libgloss dirs are already generated using autoconf-2.69.
To avoid merging new code and/or accidental regeneration using diff
versions, leverage config/override.m4 to pin to 2.69 exactly. This
matches what gcc/binutils/gdb are already doing.
The README file already says to use autoconf-2.69.
To accomplish this, it's just as simple as adding -I flags to the
top-level config/ dir when running aclocal. This is because the
override.m4 file overrides AC_INIT to first require the specific
autoconf version before calling the real AC_INIT.
- If the from_master is closed before cleaning up other pipes, such
as from_slave_nat, the same pty may be allocated and pty master may
try to open the pipe which is not closed yet, and it will fail.
This patch fixes the issue.
- Closing attach_mutex and recreating it causes the race issue
between pty and console codes. With this patch, attach_mutex
is created only once in a process which opens pty, and never
closed in order to avoid this issue.
Addresses:
https://cygwin.com/pipermail/cygwin-developers/2021-December/012548.html
- If master_fwd_thread is terminated by cygthread::terminate_thread(),
the opportunity to release tmp_pathbuf is missed, resulting in a
memory leak. This patch fixes the issue.
- GDB inferior may be suspended while the inferior grabs mutex.
This causes deadlock in terminal I/O. With this patch, timeout
for waiting mutex is set to 0 for the debugger process when the
process calls CreateProcess() with DEBUG_PROCESS flag to avoid
deadlock. This may cause the race issue in GDB, however, there
is no other way than that.
Addresses:
https://cygwin.com/pipermail/cygwin-developers/2021-December/012542.html
Drop mention of 32-bit installer, since it's offically discouraged, and
planned to be dropped soon.
Adjust various references to be something more generic, like 'the Cygwin
Setup program' to accommodate this.
Libtool needs to get BSD-format (or MS-format) output out of the system
nm, so that it can scan generated object files for symbol names for
-export-symbols-regex support. Some nms need specific flags to turn on
BSD-formatted output, so libtool checks for this in its AC_PATH_NM.
Unfortunately the code to do this has a pair of interlocking flaws:
- it runs the test by doing an nm of /dev/null. Some platforms
reasonably refuse to do an nm on a device file, but before now this
has only been worked around by assuming that the error message has a
specific textual form emitted by Tru64 nm, and that getting this
error means this is Tru64 nm and that nm -B would work to produce
BSD-format output, even though the test never actually got anything
but an error message out of nm -B. This is fixable by nm'ing *nm
itself* (since we necessarily have a path to it).
- the test is entirely skipped if NM is set in the environment, on the
grounds that the user has overridden the test: but the user cannot
reasonably be expected to know that libtool wants not only nm but
also flags forcing BSD-format output. Worse yet, one such "user" is
the top-level Cygnus configure script, which neither tests for
nor specifies any BSD-format flags. So platforms needing BSD-format
flags always fail to set them when run in a Cygnus tree, breaking
-export-symbols-regex on such platforms. Libtool also needs to
augment $LD on some platforms, but this is done unconditionally,
augmenting whatever the user specified: the nm check should do the
same.
One wrinkle: if the user has overridden $NM, a path might have been
provided: so we use the user-specified path if there was one, and
otherwise do the path search as usual. (If the nm specified doesn't
work, this might lead to a few extra pointless path searches -- but
the test is going to fail anyway, so that's not a problem.)
(Tested with NM unset, and set to nm, /usr/bin/nm, my-nm where my-nm is a
symlink to /usr/bin/nm on the PATH, and /not-on-the-path/my-nm where
*that* is a symlink to /usr/bin/nm.)
ChangeLog
2021-09-27 Nick Alcock <nick.alcock@oracle.com>
PR libctf/27967
* libtool.m4 (LT_PATH_NM): Try BSDization flags with a user-provided
NM, if there is one. Run nm on itself, not on /dev/null, to avoid
errors from nms that refuse to work on non-regular files. Remove
other workarounds for this problem. Strip out blank lines from the
nm output.
This reports common symbols like GNU nm, via a type code of 'C'.
ChangeLog
2021-09-27 Nick Alcock <nick.alcock@oracle.com>
PR libctf/27967
* libtool.m4 (lt_cv_sys_global_symbol_pipe): Augment symcode for
Solaris 11.
AR from older binutils doesn't work with --plugin and rc:
[hjl@gnu-cfl-2 bin]$ touch foo.c
[hjl@gnu-cfl-2 bin]$ ar --plugin /usr/libexec/gcc/x86_64-redhat-linux/10/liblto_plugin.so rc libfoo.a foo.c
[hjl@gnu-cfl-2 bin]$ ./ar --plugin /usr/libexec/gcc/x86_64-redhat-linux/10/liblto_plugin.so rc libfoo.a foo.c
./ar: no operation specified
[hjl@gnu-cfl-2 bin]$ ./ar --version
GNU ar (Linux/GNU Binutils) 2.29.51.0.1.20180112
Copyright (C) 2018 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or (at your option) any later version.
This program has absolutely no warranty.
[hjl@gnu-cfl-2 bin]$
Check if AR works with --plugin and rc before passing --plugin to AR and
RANLIB.
PR ld/27173
* configure: Regenerated.
* libtool.m4 (_LT_CMD_OLD_ARCHIVE): Check if AR works with
--plugin and rc before enabling --plugin.
config/
PR ld/27173
* gcc-plugin.m4 (GCC_PLUGIN_OPTION): Check if AR works with
--plugin and rc before enabling --plugin.
libiberty/
PR ld/27173
* configure: Regenerated.
zlib/
PR ld/27173
* configure: Regenerated.
When trying to run the update-gnulib.sh script in gdb, I get this:
Error: Wrong automake version (Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/\${ <-- HERE ([^ =:+{}]+)}/ at /opt/automake/1.11.1/bin/automake line 4113.), we need 1.11.1.
Aborting.
Apparently, it's an issue with a regex in automake that triggers a
warning starting with Perl 5.22. It has been fixed in automake 1.15.1.
So I think it's a good excuse to bump the versions of autoconf and
automake used in the gnulib import. And to avoid requiring multiple
builds of autoconf/automake, it was suggested that we bump the required
version of those tools for all binutils-gdb.
For autoconf, the 2.69 version is universally available, so it's an easy
choice. For automake, different distros and distro versions have
different automake versions. But 1.15.1 seems to be the most readily
available as a package. In any case, it's easy to build it from source.
I removed the version checks from AUTOMAKE_OPTIONS and AC_PREREQ,
because I don't think they are useful in our case. They only specify a
lower bound for the acceptable version of automake/autoconf. That's
useful if you let the user choose the version of the tool they want to
use, but want to set a minimum version (because you use a feature that
was introduced in that version). In our case, we force people to use a
specific version anyway. For the autoconf version, we have the check in
config/override.m4 that enforces the version we want. It will be one
less thing to update next time we change autotools version.
I hit a few categories of problems that required some changes. They are
described below along with the chosen solutions.
Problem 1:
configure.ac:17: warning: AM_INIT_AUTOMAKE: two- and three-arguments forms are deprecated. For more info, see:
configure.ac:17: http://www.gnu.org/software/automake/manual/automake.html#Modernize-AM_005fINIT_005fAUTOMAKE-invocation
Solution 1:
Adjust the code based on the example at that URL.
Problem 2 (in zlib/):
Makefile.am: error: required file './INSTALL' not found
Makefile.am: 'automake --add-missing' can install 'INSTALL'
Makefile.am: error: required file './NEWS' not found
Makefile.am: error: required file './AUTHORS' not found
Makefile.am: error: required file './COPYING' not found
Makefile.am: 'automake --add-missing' can install 'COPYING'
Solution 2:
Add the foreign option to AUTOMAKE_OPTIONS.
Problem 3:
doc/Makefile.am:20: error: support for Cygnus-style trees has been removed
Solution 3:
Remove the cygnus options.
Problem 4:
Makefile.am:656: warning: 'INCLUDES' is the old name for 'AM_CPPFLAGS' (or '*_CPPFLAGS')
Solution 4:
Rename "INCLUDES = " to "AM_CPPFLAGS += " (because AM_CPPFLAGS is
already defined earlier).
Problem 5:
doc/Makefile.am:71: warning: suffix '.texinfo' for Texinfo files is discouraged; use '.texi' instead
doc/Makefile.am: warning: Oops!
doc/Makefile.am: It appears this file (or files included by it) are triggering
doc/Makefile.am: an undocumented, soon-to-be-removed automake hack.
doc/Makefile.am: Future automake versions will no longer place in the builddir
doc/Makefile.am: (rather than in the srcdir) the generated '.info' files that
doc/Makefile.am: appear to be cleaned, by e.g. being listed in CLEANFILES or
doc/Makefile.am: DISTCLEANFILES.
doc/Makefile.am: If you want your '.info' files to be placed in the builddir
doc/Makefile.am: rather than in the srcdir, you have to use the shiny new
doc/Makefile.am: 'info-in-builddir' automake option.
Solution 5:
Rename .texinfo files to .texi.
Problem 6:
doc/Makefile.am: warning: Oops!
doc/Makefile.am: It appears this file (or files included by it) are triggering
doc/Makefile.am: an undocumented, soon-to-be-removed automake hack.
doc/Makefile.am: Future automake versions will no longer place in the builddir
doc/Makefile.am: (rather than in the srcdir) the generated '.info' files that
doc/Makefile.am: appear to be cleaned, by e.g. being listed in CLEANFILES or
doc/Makefile.am: DISTCLEANFILES.
doc/Makefile.am: If you want your '.info' files to be placed in the builddir
doc/Makefile.am: rather than in the srcdir, you have to use the shiny new
doc/Makefile.am: 'info-in-builddir' automake option.
Solution 6:
Remove the hack at the bottom of doc/Makefile.am and use
the info-in-builddir automake option.
Problem 7:
doc/Makefile.am:35: error: required file '../texinfo.tex' not found
doc/Makefile.am:35: 'automake --add-missing' can install 'texinfo.tex'
Solution 7:
Use the no-texinfo.tex automake option. We also have one in
texinfo/texinfo.tex, not sure if we should point to that, or move it
(or a newer version of it added with automake --add-missing) to
top-level.
Problem 8:
Makefile.am:131: warning: source file 'config/tc-aarch64.c' is in a subdirectory,
Makefile.am:131: but option 'subdir-objects' is disabled
automake: warning: possible forward-incompatibility.
automake: At least a source file is in a subdirectory, but the 'subdir-objects'
automake: automake option hasn't been enabled. For now, the corresponding output
automake: object file(s) will be placed in the top-level directory. However,
automake: this behaviour will change in future Automake versions: they will
automake: unconditionally cause object files to be placed in the same subdirectory
automake: of the corresponding sources.
automake: You are advised to start using 'subdir-objects' option throughout your
automake: project, to avoid future incompatibilities.
Solution 8:
Use subdir-objects, that means adjusting references to some .o that will now
be in config/.
Problem 9:
configure.ac:375: warning: AC_LANG_CONFTEST: no AC_LANG_SOURCE call detected in body
../../lib/autoconf/lang.m4:193: AC_LANG_CONFTEST is expanded from...
../../lib/autoconf/general.m4:2601: _AC_COMPILE_IFELSE is expanded from...
../../lib/autoconf/general.m4:2617: AC_COMPILE_IFELSE is expanded from...
../../lib/m4sugar/m4sh.m4:639: AS_IF is expanded from...
../../lib/autoconf/general.m4:2042: AC_CACHE_VAL is expanded from...
../../lib/autoconf/general.m4:2063: AC_CACHE_CHECK is expanded from...
configure.ac:375: the top level
Solution 9:
Use AC_LANG_SOURCE, or use proper quoting.
Problem 10 (in intl/):
configure.ac:7: warning: AC_COMPILE_IFELSE was called before AC_USE_SYSTEM_EXTENSIONS
/usr/share/aclocal/threadlib.m4:36: gl_THREADLIB_EARLY_BODY is expanded from...
/usr/share/aclocal/threadlib.m4:29: gl_THREADLIB_EARLY is expanded from...
/usr/share/aclocal/threadlib.m4:318: gl_THREADLIB is expanded from...
/usr/share/aclocal/lock.m4:9: gl_LOCK is expanded from...
/usr/share/aclocal/intl.m4:211: gt_INTL_SUBDIR_CORE is expanded from...
/usr/share/aclocal/intl.m4:25: AM_INTL_SUBDIR is expanded from...
/usr/share/aclocal/gettext.m4:57: AM_GNU_GETTEXT is expanded from...
configure.ac:7: the top level
Solution 10:
Add AC_USE_SYSTEM_EXTENSIONS in configure.ac.
ChangeLog:
* libtool.m4: Use AC_LANG_SOURCE.
* configure.ac: Remove AC_PREREQ, use AC_LANG_SOURCE.
* README-maintainer-mode: Update version requirements.
* ar-lib: New file.
* test-driver: New file.
* configure: Re-generate.
bfd/ChangeLog:
* Makefile.am (AUTOMAKE_OPTIONS): Remove 1.11.
(INCLUDES): Rename to ...
(AM_CPPFLAGS): ... this.
* configure.ac: Remove AC_PREREQ.
* doc/Makefile.am (AUTOMAKE_OPTIONS): Remove 1.9, cygnus, add
info-in-builddir no-texinfo.tex.
(info_TEXINFOS): Rename bfd.texinfo to bfd.texi.
* doc/bfd.texinfo: Rename to ...
* doc/bfd.texi: ... this.
* Makefile.in: Re-generate.
* aclocal.m4: Re-generate.
* config.in: Re-generate.
* configure: Re-generate.
* doc/Makefile.in: Re-generate.
binutils/ChangeLog:
* configure.ac: Remove AC_PREREQ.
* doc/Makefile.am (AUTOMAKE_OPTIONS): Remove cygnus, add
info-in-builddir no-texinfo.tex.
* Makefile.in: Re-generate.
* aclocal.m4: Re-generate.
* config.in: Re-generate.
* configure: Re-generate.
* doc/Makefile.in: Re-generate.
config/ChangeLog:
* override.m4 (_GCC_AUTOCONF_VERSION): Bump from 2.64 to 2.69.
etc/ChangeLog:
* configure.in: Remove AC_PREREQ.
* configure: Re-generate.
gas/ChangeLog:
* Makefile.am (AUTOMAKE_OPTIONS): Remove 1.11, add subdir-objects.
(TARG_CPU_O, OBJ_FORMAT_O, ATOF_TARG_O): Add config/ prefix.
* configure.ac (TARG_CPU_O, OBJ_FORMAT_O, ATOF_TARG_O, emfiles,
extra_objects): Add config/ prefix.
* doc/as.texinfo: Rename to...
* doc/as.texi: ... this.
* doc/Makefile.am: Rename as.texinfo to as.texi throughout.
Remove DISTCLEANFILES hack.
(AUTOMAKE_OPTIONS): Remove 1.8, cygnus, add no-texinfo.tex and
info-in-builddir.
* Makefile.in: Re-generate.
* aclocal.m4: Re-generate.
* config.in: Re-generate.
* configure: Re-generate.
* doc/Makefile.in: Re-generate.
gdb/ChangeLog:
* common/common-defs.h (PACKAGE_NAME, PACKAGE_VERSION,
PACKAGE_STRING, PACKAGE_TARNAME): Undefine.
* configure.ac: Remove AC_PREREQ, add missing quoting.
* gnulib/configure.ac: Modernize usage of
AC_INIT/AM_INIT_AUTOMAKE. Remove AC_PREREQ.
* gnulib/update-gnulib.sh (AUTOCONF_VERSION): Bump to 2.69.
(AUTOMAKE_VERSION): Bump to 1.15.1.
* configure: Re-generate.
* config.in: Re-generate.
* aclocal.m4: Re-generate.
* gnulib/aclocal.m4: Re-generate.
* gnulib/config.in: Re-generate.
* gnulib/configure: Re-generate.
* gnulib/import/Makefile.in: Re-generate.
gdb/gdbserver/ChangeLog:
* configure.ac: Remove AC_PREREQ, add missing quoting.
* configure: Re-generate.
* config.in: Re-generate.
* aclocal.m4: Re-generate.
gdb/testsuite/ChangeLog:
* configure.ac: Remove AC_PREREQ.
* configure: Re-generate.
gold/ChangeLog:
* configure.ac: Remove AC_PREREQ, add missing quoting and usage
of AC_LANG_SOURCE.
* Makefile.in: Re-generate.
* aclocal.m4: Re-generate.
* configure: Re-generate.
* testsuite/Makefile.in: Re-generate.
gprof/ChangeLog:
* configure.ac: Remove AC_PREREQ.
* Makefile.am: Remove DISTCLEANFILES hack.
(AUTOMAKE_OPTIONS): Remove 1.11, add info-in-builddir.
* Makefile.in: Re-generate.
* aclocal.m4: Re-generate.
* configure: Re-generate.
* gconfig.in: Re-generate.
intl/ChangeLog:
* configure.ac: Add AC_USE_SYSTEM_EXTENSIONS, remove AC_PREREQ.
* configure: Re-generate.
* config.h.in: Re-generate.
* aclocal.m4: Re-generate.
ld/ChangeLog:
* configure.ac: Remove AC_PREREQ.
* Makefile.am: Remove DISTCLEANFILES hack, rename ld.texinfo to
ld.texi, ldint.texinfo to ldint.texi throughout.
(AUTOMAKE_OPTIONS): Add info-in-builddir.
* README: Rename ld.texinfo to ld.texi, ldint.texinfo to
ldint.texi throughout.
* gen-doc.texi: Likewise.
* h8-doc.texi: Likewise.
* ld.texinfo: Rename to ...
* ld.texi: ... this.
* ldint.texinfo: Rename to ...
* ldint.texi: ... this.
* Makefile.in: Re-generate.
* aclocal.m4: Re-generate.
* config.in: Re-generate.
* configure: Re-generate.
libdecnumber/ChangeLog:
* configure.ac: Remove AC_PREREQ.
* configure: Re-generate.
* aclocal.m4.
libiberty/ChangeLog:
* configure.ac: Remove AC_PREREQ.
* configure: Re-generate.
* config.in: Re-generate.
opcodes/ChangeLog:
* Makefile.am (AUTOMAKE_OPTIONS): Remove 1.11.
* configure.ac: Remove AC_PREREQ.
* Makefile.in: Re-generate.
* aclocal.m4: Re-generate.
* configure: Re-generate.
readline/ChangeLog.gdb:
* configure: Re-generate.
* examples/rlfe/configure: Re-generate.
sim/ChangeLog:
* All configure.ac: Remove AC_PREREQ.
* All configure: Re-generate.
zlib/ChangeLog.bin-gdb:
* configure.ac: Modernize AC_INIT call, remove AC_PREREQ.
* Makefile.am (AUTOMAKE_OPTIONS): Remove 1.8, cygnus, add
foreign.
* Makefile.in: Re-generate.
* aclocal.m4: Re-generate.
* configure: Re-generate.
The configure scripts were regenerated with 2.69 for the newlib-4.2.0
release in 484d2ebf8d, but the aclocal
files were not. Do that now to avoid confusion between the two as to
which version of autoconf was used.
32 bit Cygwin still exports function calls to support old applications.
E. g., when switching from 16 to 32 bit uid/gid values, new function
like getuid32 have been added and the old getuid function still only
provides 16 bit values. Newly built applications using getuid are
actually calling getuid32.
However, this link magic isn't performed inside Cygwin itself, so if
newlib functions call getuid, they actually call the old getuid, not
the new getuid32. This leads to truncated uid/gid values.
https://cygwin.com/pipermail/cygwin/2022-January/250453.html reports
how this leads to problems in posix_spawn.
Fix this temporarily. i686 support will go away soon in Cygwin and the
fix can be dropped.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
We need deps to newlib's libc.a and libm.a, otherwise changes
in newlib code don't trigger a rebuild of the Cygwin DLL.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
get_posix_access() creates DEF_*_OBJ aclent_t entries from Windows ACEs
with INHERIT flags set, independent of the file type. These flags only
make sense on directory objects, but certain Windows functions don't
check the file type and allow INHERIT ACE flags even on non-directories.
As a fix, make sure to ignore the INHERIT flags on non-directory ACLs
and don't propagate the matching DEF_*_OBJ aclent_t entries to callers.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
For some RTEMS multilibs, the FPU and Altivec units are disabled during
interrupt handling. Do not save and restore the corresponding registers in
this case.
In order to transition to automake, we have to use hardcoded paths in
the AC_CONFIG_AUX_DIR macro call (since automake evaluates the path
itself, and doesn't expand vars), so simplify all the calls here.
Since automake deprecated the INCLUDES name in favor of AM_CPPFLAGS,
change all existing users over. The generated code is the same since
the two variables have been used in the same exact places by design.
There are other cleanups to be done, but lets focus on just renaming
here so we can upgrade to a newer automake version w/out triggering
new warnings.
This is simply reflecting reality: all the subdirs in here are already
using automake-1.11.6, so making it a requirement will allow us to stop
suggesting we might support automake-1.9 or 1.10 (which I'm fairly sure
do not work today).
This is why only acinclude.m4 changes in this patch: the generated files
are exactly the same as the directives here are automake constraints,
not generated code logic.