This patch adds support for the Algol 68 programming language to
Autoconf. It is based on the Algol 68 GCC front-end, which is
currently under development [1]. The front-end is temporarily hosted
in the sourceware forge until integration in GCC is completed [3].
Note that the GCC Algol 68 front-end is not yet integrated in the main
compiler, so it is developed and distributed off-tree. See
https://gcc.gnu.org/wiki/Algol68FrontEnd. Additional information
about the Algol 68 programming language, and how it is being evolved
by the GNU Algol 68 Working Group can be found at
https://algol68-lang.org.
Automake support for Algol 68 has been already pushed as of 2 February
2025.
[1] https://gcc.gnu.org/wiki/Algol68FrontEnd
[2] https://inbox.sourceware.org/gcc-patches/20250101020952.18404-1-jose.marchesi@oracle.com/T/#t
[3] https://forge.sourceforge.org/gcc/gcc-a68
Add support for the Algol68 programming language.
* lib/autoconf/a68.m4: New file.
* lib/autoconf/autoconf.m4: Include autoconf/a68.m4.
* lib/autoconf/Makefile.am (dist_autoconflib_DATA): Add a68.m4.
* lib/freeze.mk (autoconf_m4f_dependencies): Add
$(src_libdir)/autoconf/a68.m4.
* doc/autoconf.texi: Rebuild menus.
(Preset Output Variables): Mention Algol 68. Document A68FLAGS.
(Algol 68 Compiler): New subsection.
(Language Choice): Mention Algol 68.
(Generating Sources): Likewise.
(Running the Preprocessor): Likewise.
* tests/a68.at: New file.
* tests/suite.at: Include a68.at.
* tests/local.at (_AT_CHECK_ENV): Add A68 and A68FLAGS.
* NEWS: Update.
* doc/autoconf.texi (Generating Sources): Mark AC_LANG_PROGRAM
arguments as optional to match its definition and common usage.
Copyright-paperwork-exempt: yes
The current code fails with gcc r16-2729-g0d276cd378e and
-Werror=discarded-qualifiers -Werror=write-strings
(the -Werror=write-strings is useful to check compatibility of
user code with C++, and the -Werror=discarded-qualifiers is an
upgrade of a default warning to an error). Since this is a test
for C99, we may assume that const is supported by the compiler,
and adding const makes the code more robust in this context.
Copyright-paperwork-exempt: yes
Problem reported by Bruno Haible in:
https://lists.gnu.org/r/autoconf-patches/2025-06/msg00001.html
* doc/autoconf.texi (Limitations of Usual Tools):
Also mention escapes in replacement strings.
While we’re at it, update -e and -f concatenation doc.
* lib/autoconf/general.m4 (_AC_INIT_PREPARE): Emit functions ac_cache_dump,
ac_dump_debugging_info. In the trap command, invoke ac_dump_debugging_info.
(AC_CACHE_SAVE): Invoke ac_cache_dump instead of expanding _AC_CACHE_DUMP a
second time.
* lib/autoconf/general.m4 (_AC_UNDECLARED_BUILTIN):
Use shorter diagnostic, to be consistent with other changes.
(_AC_FUTURE_DARWIN): New macro.
(AC_CHECK_DECL): Require per-language _AC_FUTURE_DARWIN.
Use $ac_c_future_darwin_options alongside with
$ac_c_undeclared_builtin_options.
* NEWS: Mention the fix.
Co-authored-by: Paul Eggert <eggert@cs.ucla.edu>
* lib/autoconf/status.m4 (_AC_OUTPUT_FILES_PREPARE):
Use ‘sed -n '$='’ instead of ‘grep -c’, since these
are the only uses of grep in a minimal ‘configure’
and we are already using sed elsewhere.
Problem reported by Eric Blake in:
https://savannah.gnu.org/support/?111221
* lib/autoconf/general.m4 (_AC_DEFINE_UNQUOTED): Fix typo that
caused us to not use a here-document in some cases when we should.
* tests/torture.at (Substitute and define special characters):
Test for the bug.
Generating the tests wrapper template currently depends on the
dependencies needed for the frozen lib/m4sugar/m4sh.m4f. However,
it also requires that frozen sugar to actually be generated, or the
build will fail if it is not (or at least if it is in the process of
being generated).
Change the dependency to actually depend on the generated file, rather
than on its dependencies.
This kind of failure has been noticed on highly parallel builds on very
loaded machines.
Copyright-paperwork-exempt: yes
It is needed when building Octave targeting Windows. Without it, the
implementation of "casin" from the Windows runtime is used instead of
the replacement from MinGW-w64. That means that results for the
"casin" function are wrong without that change.
* lib/autoconf/fortran.m4: Do not remove "-lmingwex" or "-lmoldname"
from the linker flags when targeting MinGW. Removing "-lmingwex" causes
an incorrect linker resolution for functions like "casin" for projects
that consist of Fortran and C++ sources. Removing "-lmoldname" causes
issues for Fortran projects that try to use POSIX-like C functions
without a '_' symbol prefix when targeting MinGW.
Problem reported by Sean Denny in:
https://lists.gnu.org/r/bug-autoconf/2024-12/msg00001.html
* doc/autoconf.texi (Limitations of Builtins):
Document the macOS sh bug.
* tests/base.at (AC_CACHE_CHECK):
* tests/local.at: Use test -ot rather than ls -t, as POSIX
requires the former to work reliably, but does not require the
latter (POSIX does not require a stable sort for ls -t).
Somewhat ironically, this should work around the macOS bug
because the use of its buggy test -ot should increase the
timestamp resolution to 1 s.
The only platform that had this problem was native Windows,
and MSVC's malloc sets errno since 2015 at least.
* lib/autoconf/functions.m4 (AC_FUNC_MALLOC): Guess yes when
cross-compiling.
The manual was already using curved single quotes, so we
might as well use curved double quotes and en and em dashes too.
* doc/local.mk (AM_MAKEINFOFLAGS): Add ASCII_DASHES_AND_QUOTES=0,
CHECK_NORMAL_MENU_STRUCTURE=1.
* Makefile.am ($(srcdir)/INSTALL): Also use AM_MAKEINFOFLAGS.
This matches Gnulib INSTALL’s quoting practice.
* lib/autoconf/functions.m4 (_AC_FUNC_MALLOC_IF, _AC_FUNC_REALLOC_IF):
Add 3rd argument for cross-guessing; all callers changed.
Use ‘volatile’ so that compilers don’t second-guess.
Also guess yes on gnu*, midipix*, midnightbsd*.
In my Mon Oct 11 20:21:33 2004 +0000 commit when I standardized the
spelling of various acronyms in documentation and comments I spelled
it “Posix”. However, it seems that “POSIX” has won out in practice
(including my own practice!), so let’s change it back to “POSIX”.
