maint: post-release administrivia

* NEWS: Add header line for next release. * .prev-version: Record previous version. * cfg.mk (old_NEWS_hash): Auto-update.
version 3.7.6
2026-08-08 10:15:14 +00:00 · 2021-03-08 06:36:36 +01:00 · 2021-03-08 06:15:53 +01:00 · 2021-03-07 18:41:38 +01:00 · 2021-03-07 18:41:38 +01:00 · 2021-03-07 11:56:30 +01:00
250 changed files with 2287 additions and 1273 deletions
@@ -1 +1 @@
-3.7
+3.7.6
@@ -50,6 +50,7 @@ jobs:
        - make -j2 dist-xz
        # Can help understanding why we get "dirty" tarballs.
        - git status
+        - git diff
        - dist=$(echo bison*.xz)

        # Unfortunately we cannot deterministically know the name of the tarball without the full
@@ -129,7 +130,7 @@ jobs:
        - CC=icc
        - CXX=icpc
      install:
-        - source /opt/intel/inteloneapi/compiler/latest/env/vars.sh
+        - source /opt/intel/oneapi/compiler/latest/env/vars.sh
      addons:
        apt:
          sources:
@@ -24,7 +24,7 @@ and nasty bugs.

 -----

-Copyright (C) 1998-2015, 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 1998-2015, 2018-2021 Free Software Foundation, Inc.

 This file is part of Bison, the GNU Compiler Compiler.

@@ -39,4 +39,4 @@ 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 <http://www.gnu.org/licenses/>.
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
@@ -1,7 +1,7 @@
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

- Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

@@ -645,7 +645,7 @@ the "copyright" line and a pointer to where the full notice is found.
    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 <http://www.gnu.org/licenses/>.
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.

 Also add information on how to contact you by electronic and paper mail.

@@ -664,11 +664,11 @@ might be different; for a GUI interface, you would use an "about box".
  You should also get your employer (if you work as a programmer) or school,
 if any, to sign a "copyright disclaimer" for the program, if necessary.
 For more information on this, and how to apply and follow the GNU GPL, see
-<http://www.gnu.org/licenses/>.
+<https://www.gnu.org/licenses/>.

  The GNU General Public License does not permit incorporating your program
 into proprietary programs.  If your program is a subroutine library, you
 may consider it more useful to permit linking proprietary applications with
 the library.  If this is what you want to do, use the GNU Lesser General
 Public License instead of this License.  But first, please read
-<http://www.gnu.org/philosophy/why-not-lgpl.html>.
+<https://www.gnu.org/licenses/why-not-lgpl.html>.
@@ -1,6 +1,6 @@
 ## Process this file with automake to produce Makefile.in.

-# Copyright (C) 2001-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2001-2015, 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 AUTOMAKE_OPTIONS = subdir-objects
 ACLOCAL_AMFLAGS = -I m4
@@ -133,9 +133,10 @@ gen-ChangeLog:
 	$(CC) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -o $@ -E $<

 .PHONY: codespell
+CODESPELL = codespell
 codespell:
 	$(AM_V_GEN) cd $(srcdir) \
-	&& codespell \
+	&& $(CODESPELL) \
 	     --regex "[\\w\\-'’\`]+\+*" \
 	     --ignore-words-list "ba,circularly,cloneable,copyable,define'd,dout,froms,iff,ifset,od,ois" \
 	     $$(git ls-files data doc lib src tests)
@@ -1,5 +1,108 @@
 GNU Bison NEWS

+* Noteworthy changes in release ?.? (????-??-??) [?]
+
+
+* Noteworthy changes in release 3.7.6 (2021-03-08) [stable]
+
+** Bug fixes
+
+*** Reused Push Parsers
+
+  When a push-parser state structure is used for multiple parses, it was
+  possible for some state to leak from one run into the following one.
+
+*** Fix Table Generation
+
+  In some very rare conditions, when there are many useless tokens, it was
+  possible to generate incorrect parsers.
+
+
+* Noteworthy changes in release 3.7.5 (2021-01-24) [stable]
+
+** Bug fixes
+
+*** Counterexample Generation
+
+  In some cases counterexample generation could crash.  This is fixed.
+
+*** Fix Table Generation
+
+  In some very rare conditions, when there are many useless tokens, it was
+  possible to generate incorrect parsers.
+
+*** GLR parsers now support %merge together with api.value.type=union.
+
+*** C++ parsers use noexcept in more places.
+
+*** Generated parsers avoid some warnings about signedness issues.
+
+*** C-language parsers now avoid warnings from pedantic clang.
+
+*** C-language parsers now work around quirks of HP-UX 11.23 (2003).
+
+
+* Noteworthy changes in release 3.7.4 (2020-11-14) [stable]
+
+** Bug fixes
+
+*** Bug fixes in yacc.c
+
+  In Yacc mode, all the tokens are defined twice: once as an enum, and then
+  as a macro.  YYEMPTY was missing its macro.
+
+*** Bug fixes in lalr1.cc
+
+  The lalr1.cc skeleton used to emit internal assertions (using YY_ASSERT)
+  even when the `parse.assert` %define variable is not enabled.  It no
+  longer does.
+
+  The private internal macro YY_ASSERT now obeys the `api.prefix` %define
+  variable.
+
+  When there is a very large number of tokens, some assertions could be long
+  enough to hit arbitrary limits in Visual C++.  They have been rewritten to
+  work around this limitation.
+
+** Changes
+
+  The YYBISON macro in generated "regular C parsers" (from the "yacc.c"
+  skeleton) used to be defined to 1.  It is now defined to the version of
+  Bison as an integer (e.g., 30704 for version 3.7.4).
+
+* Noteworthy changes in release 3.7.3 (2020-10-13) [stable]
+
+** Bug fixes
+
+  Fix concurrent build issues.
+
+  The bison executable is no longer linked uselessly against libreadline.
+
+  Fix incorrect use of yytname in glr.cc.
+
+* Noteworthy changes in release 3.7.2 (2020-09-05) [stable]
+
+  This release of Bison fixes all known bugs reported for Bison in MITRE's
+  Common Vulnerabilities and Exposures (CVE) system.  These vulnerabilities
+  are only about bison-the-program itself, not the generated code.
+
+  Although these bugs are typically irrelevant to how Bison is used, they
+  are worth fixing if only to give users peace of mind.
+
+  There is no known vulnerability in the generated parsers.
+
+** Bug fixes
+
+  Fix concurrent build issues (introduced in Bison 3.5).
+
+  Push parsers always use YYMALLOC/YYFREE (no direct calls to malloc/free).
+
+  Fix portability issues of the test suite, and of bison itself.
+
+  Some unlikely crashes found by fuzzing have been fixed.  This is only
+  about bison itself, not the generated parsers.
+
+
 * Noteworthy changes in release 3.7.1 (2020-08-02) [stable]

 ** Bug fixes
@@ -196,7 +299,7 @@ GNU Bison NEWS
  parse errors, since `yynerrs` was also reset.  This can be especially
  troublesome when used in autocompletion, since a parser with error
  recovery would suggest (irrelevant) expected tokens even if there were
-  failure.
+  failures.

  Now the parser state can be examined when parsing is finished.  The parser
  state is reset when starting a new parse.
@@ -554,7 +657,8 @@ GNU Bison NEWS
  \005) with incorrect styling.  Fixes for similar issues with unexpectedly
  short lines (e.g., the file was changed between parsing and diagnosing).

-  Several unlikely crashes found by fuzzing have been fixed.
+  Some unlikely crashes found by fuzzing have been fixed.  This is only
+  about bison itself, not the generated parsers.


 * Noteworthy changes in release 3.5.2 (2020-02-13) [stable]
@@ -3314,7 +3418,7 @@ GNU Bison NEWS
  inherent flaws when %error-verbose or "#define YYERROR_VERBOSE" is
  used.  For a more detailed discussion, see:

-    http://lists.gnu.org/archive/html/bison-patches/2009-12/msg00024.html
+    https://lists.gnu.org/r/bison-patches/2009-12/msg00024.html

  The upcoming Bison 2.5 will remove YYFAIL from Java parsers, but
  deterministic parsers in C will continue to implement it.  However,
@@ -4070,7 +4174,7 @@ GNU Bison NEWS
  error token.  The new behavior has long been the documented behavior,
  and has long been required by POSIX.  For more details, please see
  Paul Eggert, "Reductions during Bison error handling" (2002-05-20)
-  <http://lists.gnu.org/archive/html/bug-bison/2002-05/msg00038.html>.
+  <https://lists.gnu.org/r/bug-bison/2002-05/msg00038.html>.

 ** Traces
  Popped tokens and nonterminals are now reported.
@@ -4486,7 +4590,7 @@ mode: outline
 fill-column: 76
 End:

-Copyright (C) 1995-2015, 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 1995-2015, 2018-2021 Free Software Foundation, Inc.

 This file is part of Bison, the GNU Parser Generator.

@@ -36,7 +36,7 @@ to the bison package.

 -----

-Copyright (C) 2002, 2005, 2009-2015, 2018-2020 Free Software Foundation,
+Copyright (C) 2002, 2005, 2009-2015, 2018-2021 Free Software Foundation,
 Inc.

 This file is part of Bison, the GNU Compiler Compiler.
@@ -52,4 +52,4 @@ 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 <http://www.gnu.org/licenses/>.
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
@@ -27,7 +27,7 @@ Bison from the git repo.  Roughly, run:
 then proceed with the usual `configure && make` steps.

 ## Build from tarball
-See the [INSTALL file](INSTALL] for generic compilation and installation
+See the [INSTALL file](INSTALL) for generic compilation and installation
 instructions.

 Bison requires GNU m4 1.4.6 or later.  See
@@ -87,7 +87,7 @@ for the user-side parser execution).  The requirements between both differ:
 bison needs ngettext, the generated parsers do not.  To simplify the build
 system, neither are installed if ngettext is not supported, even if
 generated parsers could have been localized.  See
-http://lists.gnu.org/archive/html/bug-bison/2009-08/msg00006.html for more
+https://lists.gnu.org/r/bug-bison/2009-08/msg00006.html for more
 details.

 # Questions
@@ -120,7 +120,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 1992, 1998-1999, 2003-2005, 2008-2015, 2018-2020 Free
+Copyright (C) 1992, 1998-1999, 2003-2005, 2008-2015, 2018-2021 Free
 Software Foundation, Inc.

 This file is part of GNU bison, the GNU Compiler Compiler.
@@ -12,7 +12,7 @@ the problems you encounter.

 -----

-Copyright (C) 2002, 2004, 2009-2015, 2018-2020 Free Software Foundation,
+Copyright (C) 2002, 2004, 2009-2015, 2018-2021 Free Software Foundation,
 Inc.

 This file is part of GNU Bison.
@@ -28,4 +28,4 @@ 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 <http://www.gnu.org/licenses/>.
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
@@ -2,7 +2,7 @@ This file attempts to describe the rules to use when hacking Bison.
 Don't put this file into the distribution.

 Everything related to the development of Bison is on Savannah:
-http://savannah.gnu.org/projects/bison/.
+https://savannah.gnu.org/projects/bison/.


 Working from the Repository
@@ -19,21 +19,21 @@ requirements on anyone wishing to build from the just-checked-out sources.
 For example, you have to use the latest stable versions of the maintainer
 tools we depend upon, including:

- Autoconf <http://www.gnu.org/software/autoconf/>
- Automake <http://www.gnu.org/software/automake/>
- Flex <http://www.gnu.org/software/flex/>
- Gettext <http://www.gnu.org/software/gettext/>
- Gperf <http://www.gnu.org/software/gperf/>
- Graphviz <http://www.graphviz.org>
- Gzip <http://www.gnu.org/software/gzip/>
- Help2man <http://www.gnu.org/software/help2man/>
- Perl <http://www.cpan.org/>
- Rsync <http://samba.anu.edu.au/rsync/>
- Tar <http://www.gnu.org/software/tar/>
- Texinfo <http://www.gnu.org/software/texinfo/>
+- Autoconf <https://www.gnu.org/software/autoconf/>
+- Automake <https://www.gnu.org/software/automake/>
+- Flex <https://www.gnu.org/software/flex/>
+- Gettext <https://www.gnu.org/software/gettext/>
+- Gperf <https://www.gnu.org/software/gperf/>
+- Graphviz <https://www.graphviz.org>
+- Gzip <https://www.gnu.org/software/gzip/>
+- Help2man <https://www.gnu.org/software/help2man/>
+- Perl <https://www.cpan.org/>
+- Rsync <https://rsync.samba.org/>
+- Tar <https://www.gnu.org/software/tar/>
+- Texinfo <https://www.gnu.org/software/texinfo/>

-Valgrind <http://valgrind.org/> is also highly recommended, if it supports
-your architecture.
+Valgrind <https://www.valgrind.org/> is also highly recommended, if it
+supports your architecture.

 If you're using a GNU/Linux distribution, the easiest way to install the
 above packages depends on your system.  The following shell command should
@@ -57,7 +57,7 @@ might be needed.

 Obviously, if you are reading these notes, you did manage to check out this
 package from the repository.  For the record, you will find all the relevant
-information on http://savannah.gnu.org/git/?group=bison.
+information on https://savannah.gnu.org/git/?group=bison.

 Bison uses Git submodules: subscriptions to other Git repositories.  In
 particular it uses gnulib, the GNU portability library.  To ask Git to
@@ -139,7 +139,7 @@ Register your changes.

 For a suggestion of what gnulib commit might be stable enough for a formal
 release, see the ChangeLog in the latest gnulib snapshot at
-http://erislabs.net/ianb/projects/gnulib/.
+https://erislabs.net/ianb/projects/gnulib/.

 The Autoconf files we use are currently:
 - m4/m4.m4
@@ -246,7 +246,7 @@ Prefer `res` as the name of the local variable that will be "return"ed by
 the function.

 In writing arithmetic comparisons, use "<" and "<=" rather than ">" and ">="
-(http://www.gelato.unsw.edu.au/archives/git/0505/4507.html).
+<https://public-inbox.org/git/7vfyw7yebj.fsf_-_@assigned-by-dhcp.cox.net/>.

 ### Bison
 Follow the GNU Coding Standards.
@@ -325,7 +325,7 @@ about the C standard introducing such a name.

 #### C++
 Follow the [C++ Core
-Guidelines](http://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines).
+Guidelines](https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines).
 The [Google ones](https://google.github.io/styleguide/cppguide.html) may be
 interesting too.

@@ -512,7 +512,7 @@ release:
 - Maybe build with -DGNULIB_POSIXCHECK, which suggests gnulib modules that
  can fix portability issues.  See if you really want to pay attention to
  its warnings; there's no need to obey blindly to it
-  (<http://lists.gnu.org/archive/html/bison-patches/2012-05/msg00057.html>).
+  (<https://lists.gnu.org/r/bison-patches/2012-05/msg00057.html>).

 - Check with `make syntax-check` if there are issues diagnosed by gnulib.

@@ -569,7 +569,7 @@ bootstrapped.

 <!--

-Copyright (C) 2002-2005, 2007-2015, 2018-2020 Free Software Foundation,
+Copyright (C) 2002-2005, 2007-2015, 2018-2021 Free Software Foundation,
 Inc.

 This file is part of GNU Bison.
@@ -585,7 +585,7 @@ 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 <http://www.gnu.org/licenses/>.
+along with this program.  If not, see <https://www.gnu.org/licenses/>.

 Local Variables:
 mode: markdown
@@ -237,7 +237,7 @@ End:

 -----

-Copyright (C) 2000-2015, 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 2000-2015, 2018-2021 Free Software Foundation, Inc.

 This file is part of Bison, the GNU Parser Generator.

@@ -252,4 +252,4 @@ 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 <http://www.gnu.org/licenses/>.
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
@@ -1,4 +1,12 @@
-* Bison 3.7
+* Soon
+** gnulib
+Bruno notes:
+
+> I haven't looked deeply, but it strikes me that gnulib/lib/bitset/array.c
+> does not make use of the 'ffsl' function, nor or the 'integer_length_l'
+> function. Maybe because in Bison, all bitsets are so dense that it does
+> not give a performance advantage?
+
 ** Cex
 *** Improve gnulib
 Don't do this (counterexample.c):
@@ -720,7 +728,7 @@ This is a popular demand.  We already made many changes in the parser that
 should make this reasonably easy to implement.

 Bruce Mardle <[email protected]>
-https://lists.gnu.org/archive/html/bison-patches/2015-09/msg00000.html
+https://lists.gnu.org/r/bison-patches/2015-09/msg00000.html

 However, there are many other things to do before having such a feature,
 because I don't want a % equivalent to #include (which we all learned to
@@ -733,7 +741,7 @@ There is demand for push parsers in Java and C++.  And GLR I guess.

 ** Generate code instead of tables
 This is certainly quite a lot of work.  See
-http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.50.4539.
+https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.50.4539.

 ** $-1
 We should find a means to provide an access to values deep in the
@@ -869,7 +877,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2001-2004, 2006, 2008-2015, 2018-2020 Free Software
+Copyright (C) 2001-2004, 2006, 2008-2015, 2018-2021 Free Software
 Foundation, Inc.

 This file is part of Bison, the GNU Compiler Compiler.
@@ -1,6 +1,6 @@
 # Bootstrap configuration.

-# Copyright (C) 2006-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2006-2015, 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 # gnulib modules used by this package.
 gnulib_modules='
@@ -1,4 +1,4 @@
-# Copyright (C) 2012-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2012-2015, 2018-2021 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
@@ -11,7 +11,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 # Valgrind suppression file for Bison.

@@ -1,4 +1,4 @@
-# Copyright (C) 2012-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2012-2015, 2018-2021 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
@@ -11,7 +11,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 # Valgrind suppression file for Bison.

@@ -2,7 +2,7 @@

 # Generate a release announcement message.

-# Copyright (C) 2007-2020 Free Software Foundation, Inc.
+# Copyright (C) 2007-2021 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
@@ -1,4 +1,4 @@
-## Copyright (C) 2000-2015, 2018-2020 Free Software Foundation, Inc.
+## Copyright (C) 2000-2015, 2018-2021 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
@@ -11,7 +11,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 EXTRA_DIST +=					\
  build-aux/Darwin.valgrind			\
@@ -3,7 +3,7 @@
 # Update b4_copyright invocations or b4_copyright_years definitions to
 # include the current year.

-# Copyright (C) 2009-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2009-2015, 2018-2021 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
@@ -16,7 +16,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 use strict;
 use warnings;
@@ -2,7 +2,7 @@

 # In configure.ac, update PACKAGE_COPYRIGHT_YEAR to the current year.

-# Copyright (C) 2010-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2010-2015, 2018-2021 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
@@ -15,7 +15,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 use strict;
 use warnings;
@@ -2,7 +2,7 @@

 # Update expectations in an Autotest test suite.

-# Copyright (C) 2019-2020 Free Software Foundation, Inc.
+# Copyright (C) 2019-2021 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
@@ -1,5 +1,5 @@
 ## Customize maint.mk                           -*- makefile -*-
-## Copyright (C) 2008-2015, 2018-2020 Free Software Foundation, Inc.
+## Copyright (C) 2008-2015, 2018-2021 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
@@ -12,7 +12,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 # Update version, then recompile so that tests/bison --version be
 # up-to-date, then compile our parser again with our up-to-date bison.
@@ -126,7 +126,7 @@ _sed_rm_comments_q = $(subst ','\'',$(_sed_remove_comments))

 _space_before_paren_exempt =? \\n\\$$
 _space_before_paren_exempt = \
-  (^ *\#|(LA)?LR\([01]\)|percent_(code|define)|b4_syncline|m4_(define|init)|symbol)
+  (^ *\#|(LA)?LR\([01]\)|percent_(code|define)|b4_syncline|m4_(define|init))
 # Ensure that there is a space before each open parenthesis in C code.
 sc_space_before_open_paren:
 	@if $(VC_LIST_EXCEPT) | grep -l '\.[ch]$$' > /dev/null; then	\
@@ -156,6 +156,8 @@ exclude = \
 $(call exclude,                                                                 \
  bindtextdomain=^lib/main.c$$                                                  \
  cast_of_argument_to_free=^src/muscle-tab.c$$                                  \
+  copyright_check=gnulib/lib/version-etc.c$$                                    \
+  error_message_uppercase=etc/bench.pl.in$$                                     \
  po_check=^tests|(^po/POTFILES.in|.md)$$                                       \
  preprocessor_indentation=^data/|^lib/|^src/parse-gram.[ch]$$                  \
  program_name=^lib/main.c$$                                                    \
@@ -1,6 +1,6 @@
 # Configure template for GNU Bison.                   -*-Autoconf-*-
 #
-# Copyright (C) 2001-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2001-2015, 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 # In order for some versions of Sun Studio to compile our C++ test cases
 # correctly, we need Autoconf 2.64 or better to handle the restrict
@@ -29,7 +29,7 @@ AC_INIT([GNU Bison],
        [[email protected]],
        [],
        [https://www.gnu.org/software/bison/])
-AC_SUBST([PACKAGE_COPYRIGHT_YEAR], [2020])
+AC_SUBST([PACKAGE_COPYRIGHT_YEAR], [2021])
 AC_DEFINE_UNQUOTED([PACKAGE_COPYRIGHT_YEAR], [$PACKAGE_COPYRIGHT_YEAR],
                   [The copyright year for this package])

@@ -142,11 +142,17 @@ The macro `b4_symbol(NUM, FIELD)` gives access to the following FIELDS:
  When api.value.type=union, the generated name for the union member.
  yytype_INT etc. for symbols that has_id, otherwise yytype_1 etc.

- `type`
+- `type`: string
  If it has a semantic value, its type tag, or, if variant are used,
  its type.
  In the case of api.value.type=union, type is the real type (e.g. int).

+- `slot`: string
+  If it has a semantic value, the name of the union member (i.e., bounces to
+  either `type_tag` or `type`).  It would be better to fix our mess and
+  always use `type` for the true type of the member, and `type_tag` for the
+  name of the union member.
+
 - `has_printer`: 0, 1
 - `printer`: string
 - `printer_file`: string
@@ -187,7 +193,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2002, 2008-2015, 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 2002, 2008-2015, 2018-2021 Free Software Foundation, Inc.

 This file is part of GNU Bison.

@@ -202,6 +208,6 @@ 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 <http://www.gnu.org/licenses/>.
+along with this program.  If not, see <https://www.gnu.org/licenses/>.

 -->
@@ -1,5 +1,5 @@
 /* Default styling rules for Bison when doing terminal output.
-   Copyright (C) 2019-2020 Free Software Foundation, Inc.
+   Copyright (C) 2019-2021 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
@@ -1,4 +1,4 @@
-## Copyright (C) 2002, 2005-2015, 2018-2020 Free Software Foundation,
+## Copyright (C) 2002, 2005-2015, 2018-2021 Free Software Foundation,
 ## Inc.

 ## This program is free software: you can redistribute it and/or modify
@@ -12,7 +12,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 dist_pkgdata_DATA =                             \
  data/README.md                                \
@@ -2,7 +2,7 @@

 # Language-independent M4 Macros for Bison.

-# Copyright (C) 2002, 2004-2015, 2018-2020 Free Software Foundation,
+# Copyright (C) 2002, 2004-2015, 2018-2021 Free Software Foundation,
 # Inc.

 # This program is free software: you can redistribute it and/or modify
@@ -16,7 +16,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.



@@ -49,7 +49,7 @@ m4_define([m4_shift4], [m4_shift(m4_shift(m4_shift(m4_shift($@))))])
 # b4_generated_by
 # ---------------
 m4_define([b4_generated_by],
-[b4_comment([A Bison parser, made by GNU Bison b4_version.])
+[b4_comment([A Bison parser, made by GNU Bison b4_version_string.])
 ])

 # b4_copyright(TITLE, [YEARS])
@@ -74,7 +74,7 @@ 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 <http://www.gnu.org/licenses/>.])
+along with this program.  If not, see <https://www.gnu.org/licenses/>.])

 b4_comment([As a special exception, you may create a larger work that contains
 part or all of the Bison parser skeleton and distribute that work
@@ -465,6 +465,19 @@ m4_case([$1],
 # but are S_YYEMPTY and symbol_kind::S_YYEMPTY in C++.
 m4_copy([b4_symbol_kind_base], [b4_symbol_kind])

+
+# b4_symbol_slot(NUM)
+# -------------------
+# The name of union member that contains the value of these symbols.
+# Currently, we are messy, this should actually be type_tag, but type_tag
+# has several meanings.
+m4_define([b4_symbol_slot],
+[m4_case(b4_percent_define_get([[api.value.type]]),
+         [union],   [b4_symbol([$1], [type_tag])],
+         [variant], [b4_symbol([$1], [type_tag])],
+         [b4_symbol([$1], [type])])])
+
+
 # b4_symbol(NUM, FIELD)
 # ---------------------
 # Fetch FIELD of symbol #NUM (or "orig NUM").  Fail if undefined.
@@ -475,6 +488,7 @@ m4_define([b4_symbol],
         [id],        [b4_symbol_token_kind([$1])],
         [kind_base], [b4_symbol_kind_base([$1])],
         [kind],      [b4_symbol_kind([$1])],
+         [slot],      [b4_symbol_slot([$1])],
         [_b4_symbol($@)])])


@@ -537,7 +551,7 @@ m4_defn([b4_actions_])[]dnl
        break;
    }dnl
 ],
-[YYUSE (m4_default([$2], [yykind]));])dnl
+[YY_USE (m4_default([$2], [yykind]));])dnl
 m4_popdef([b4_actions_])dnl
 ])

@@ -633,11 +647,11 @@ m4_define([_b4_type_action],

 ])])

-# b4_type_foreach(MACRO)
-# ----------------------
+# b4_type_foreach(MACRO, [SEP])
+# -----------------------------
 # Invoke MACRO(SYMBOL-NUMS) for each set of SYMBOL-NUMS for each type set.
 m4_define([b4_type_foreach],
-          [m4_map([$1], m4_defn([b4_type_names]))])
+          [m4_map_sep([$1], [$2], m4_defn([b4_type_names]))])



@@ -2,7 +2,7 @@

 # C++ skeleton dispatching for Bison.

-# Copyright (C) 2006-2007, 2009-2015, 2018-2020 Free Software
+# Copyright (C) 2006-2007, 2009-2015, 2018-2021 Free Software
 # Foundation, Inc.

 # This program is free software: you can redistribute it and/or modify
@@ -16,7 +16,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 b4_glr_if(             [m4_define([b4_used_skeleton], [b4_skeletonsdir/[glr.cc]])])
 b4_nondeterministic_if([m4_define([b4_used_skeleton], [b4_skeletonsdir/[glr.cc]])])
@@ -2,7 +2,7 @@

 # C++ skeleton for Bison

-# Copyright (C) 2002-2020 Free Software Foundation, Inc.
+# Copyright (C) 2002-2021 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
@@ -15,7 +15,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 # Sanity checks, before defaults installed by c.m4.
 b4_percent_define_ifdef([[api.value.union.name]],
@@ -321,8 +321,9 @@ m4_define([b4_symbol_type_define],
      /// Copy constructor.
      basic_symbol (const basic_symbol& that);]b4_variant_if([[

-      /// Constructor for valueless symbols, and symbols from each type.
-]b4_type_foreach([b4_basic_symbol_constructor_define])], [[
+      /// Constructors for typed symbols.
+]b4_type_foreach([b4_basic_symbol_constructor_define], [
+])], [[
      /// Constructor for valueless symbols.
      basic_symbol (typename Base::kind_type t]b4_locations_if([,
                    YY_MOVE_REF (location_type) l])[);
@@ -339,7 +340,7 @@ m4_define([b4_symbol_type_define],
      }

      /// Destroy contents, and record that is empty.
-      void clear ()
+      void clear () YY_NOEXCEPT
      {]b4_variant_if([[
        // User destructor.
        symbol_kind_type yykind = this->kind ();
@@ -423,7 +424,7 @@ m4_define([b4_symbol_type_define],
      by_kind (kind_type t);

      /// Record that this symbol is empty.
-      void clear ();
+      void clear () YY_NOEXCEPT;

      /// Steal the symbol kind from \a that.
      void move (by_kind& that);
@@ -543,7 +544,7 @@ m4_define([b4_public_types_define],
  {}

  ]b4_inline([$1])[void
-  ]b4_parser_class[::by_kind::clear ()
+  ]b4_parser_class[::by_kind::clear () YY_NOEXCEPT
  {
    kind_ = ]b4_symbol(-2, kind)[;
  }
@@ -2,7 +2,7 @@

 # Common code for C-like languages (C, C++, Java, etc.)

-# Copyright (C) 2012-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2012-2015, 2018-2021 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
@@ -15,7 +15,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.


 # _b4_comment(TEXT, OPEN, CONTINUE, END)
@@ -2,7 +2,7 @@

 # C skeleton dispatching for Bison.

-# Copyright (C) 2006-2007, 2009-2015, 2018-2020 Free Software
+# Copyright (C) 2006-2007, 2009-2015, 2018-2021 Free Software
 # Foundation, Inc.

 # This program is free software: you can redistribute it and/or modify
@@ -16,7 +16,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 b4_glr_if(             [m4_define([b4_used_skeleton], [b4_skeletonsdir/[glr.c]])])
 b4_nondeterministic_if([m4_define([b4_used_skeleton], [b4_skeletonsdir/[glr.c]])])
@@ -2,7 +2,7 @@

 # C M4 Macros for Bison.

-# Copyright (C) 2002, 2004-2015, 2018-2020 Free Software Foundation,
+# Copyright (C) 2002, 2004-2015, 2018-2021 Free Software Foundation,
 # Inc.

 # This program is free software: you can redistribute it and/or modify
@@ -16,7 +16,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 m4_include(b4_skeletonsdir/[c-like.m4])

@@ -58,11 +58,11 @@ m4_define([b4_cpp_guard_close],
 # b4_pull_flag if they use the values of the %define variables api.pure or
 # api.push-pull.
 m4_define([b4_identification],
-[[/* Identify Bison output.  */
-#define YYBISON 1
+[[/* Identify Bison output, and Bison version.  */
+#define YYBISON ]b4_version[

-/* Bison version.  */
-#define YYBISON_VERSION "]b4_version["
+/* Bison version string.  */
+#define YYBISON_VERSION "]b4_version_string["

 /* Skeleton name.  */
 #define YYSKELETON_NAME ]b4_skeleton[]m4_ifdef([b4_pure_flag], [[
@@ -160,11 +160,11 @@ m4_popdef([$1])dnl

 # b4_parse_param_use([VAL], [LOC])
 # --------------------------------
-# 'YYUSE' VAL, LOC if locations are enabled, and all the parse-params.
+# 'YY_USE' VAL, LOC if locations are enabled, and all the parse-params.
 m4_define([b4_parse_param_use],
-[m4_ifvaln([$1], [  YYUSE ([$1]);])dnl
-b4_locations_if([m4_ifvaln([$2], [  YYUSE ([$2]);])])dnl
-b4_parse_param_for([Decl], [Formal], [  YYUSE (Formal);
+[m4_ifvaln([$1], [  YY_USE ([$1]);])dnl
+b4_locations_if([m4_ifvaln([$2], [  YY_USE ([$2]);])])dnl
+b4_parse_param_for([Decl], [Formal], [  YY_USE (Formal);
 ])dnl
 ])

@@ -242,6 +242,18 @@ typedef int_least16_t yytype_int16;
 typedef short yytype_int16;
 #endif

+/* Work around bug in HP-UX 11.23, which defines these macros
+   incorrectly for preprocessor constants.  This workaround can likely
+   be removed in 2023, as HPE has promised support for HP-UX 11.23
+   (aka HP-UX 11i v2) only through the end of 2022; see Table 2 of
+   <https://h20195.www2.hpe.com/V2/getpdf.aspx/4AA4-7673ENW.pdf>.  */
+#ifdef __hpux
+# undef UINT_LEAST8_MAX
+# undef UINT_LEAST16_MAX
+# define UINT_LEAST8_MAX 255
+# define UINT_LEAST16_MAX 65535
+#endif
+
 #if defined __UINT_LEAST8_MAX__ && __UINT_LEAST8_MAX__ <= __INT_MAX__
 typedef __UINT_LEAST8_TYPE__ yytype_uint8;
 #elif (!defined __UINT_LEAST8_MAX__ && defined YY_STDINT_H \
@@ -366,14 +378,16 @@ dnl use C' _Noreturn in C++, to avoid -Wc11-extensions warnings.
      && ((201103 <= __cplusplus && !(__GNUC__ == 4 && __GNUC_MINOR__ == 7)) \
          || (defined _MSC_VER && 1900 <= _MSC_VER)))
 #  define _Noreturn [[noreturn]]
-# elif (!defined __cplusplus                     \
-        && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0)  \
-            || 4 < __GNUC__ + (7 <= __GNUC_MINOR__) \
-            || (defined __apple_build_version__ \
-                ? 6000000 <= __apple_build_version__ \
-                : 3 < __clang_major__ + (5 <= __clang_minor__))))
+# elif ((!defined __cplusplus || defined __clang__) \
+        && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
+            || (!defined __STRICT_ANSI__ \
+                && (__4 < __GNUC__ + (7 <= __GNUC_MINOR__) \
+                    || (defined __apple_build_version__ \
+                        ? 6000000 <= __apple_build_version__ \
+                        : 3 < __clang_major__ + (5 <= __clang_minor__))))))
   /* _Noreturn works as-is.  */
-# elif 2 < __GNUC__ + (8 <= __GNUC_MINOR__) || 0x5110 <= __SUNPRO_C
+# elif (2 < __GNUC__ + (8 <= __GNUC_MINOR__) || defined __clang__ \
+        || 0x5110 <= __SUNPRO_C)
 #  define _Noreturn __attribute__ ((__noreturn__))
 # elif 1200 <= (defined _MSC_VER ? _MSC_VER : 0)
 #  define _Noreturn __declspec (noreturn)
@@ -384,9 +398,9 @@ dnl use C' _Noreturn in C++, to avoid -Wc11-extensions warnings.

 ]])[/* Suppress unused-variable warnings by "using" E.  */
 #if ! defined lint || defined __GNUC__
-# define YYUSE(E) ((void) (E))
+# define YY_USE(E) ((void) (E))
 #else
-# define YYUSE(E) /* empty */
+# define YY_USE(E) /* empty */
 #endif

 #if defined __GNUC__ && ! defined __ICC && 407 <= __GNUC__ * 100 + __GNUC_MINOR__
@@ -509,10 +523,11 @@ m4_define([b4_token_define],
 # ----------------
 # Output the definition of the tokens.
 m4_define([b4_token_defines],
-[b4_any_token_visible_if([/* Token kinds.  */
-m4_join([
+[[/* Token kinds.  */
+#define ]b4_symbol([-2], [id])[ -2
+]m4_join([
 ], b4_symbol_map([b4_token_define]))
-])])
+])


 # b4_token_enum(TOKEN-NUM)
@@ -2,7 +2,7 @@

 # D skeleton dispatching for Bison.

-# Copyright (C) 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2018-2021 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
@@ -15,7 +15,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 b4_glr_if(             [b4_complain([%%glr-parser not supported for D])])
 b4_nondeterministic_if([b4_complain([%%nondeterministic-parser not supported for D])])
@@ -2,7 +2,7 @@

 # D language support for Bison

-# Copyright (C) 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2018-2021 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
@@ -15,7 +15,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.


 # _b4_comment(TEXT, OPEN, CONTINUE, END)
@@ -103,12 +103,12 @@ m4_define([b4_location_type_if],
 # b4_identification
 # -----------------
 m4_define([b4_identification],
-[/** Version number for the Bison executable that generated this parser.  */
-  public static immutable string yy_bison_version = "b4_version";
+[[/** Version number for the Bison executable that generated this parser.  */
+  public static immutable string yy_bison_version = "]b4_version_string[";

  /** Name of the skeleton that generated this parser.  */
-  public static immutable string yy_bison_skeleton = b4_skeleton;
-])
+  public static immutable string yy_bison_skeleton = ]b4_skeleton[;
+]])


 ## ------------ ##
@@ -1,8 +1,8 @@
-                                                                    -*- C -*-
+#                                                             -*- C -*-

 # GLR skeleton for Bison

-# Copyright (C) 2002-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2002-2015, 2018-2021 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
@@ -15,7 +15,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.


 # If we are loaded by glr.cc, do not override c++.m4 definitions by
@@ -145,6 +145,15 @@ m4_define([b4_rhs_location],
 [(b4_rhs_data([$1], [$2]).yyloc)])


+# b4_call_merger(MERGER-NUM, MERGER-NAME, SYMBOL-SUM)
+# ---------------------------------------------------
+m4_define([b4_call_merger],
+[b4_case([$1],
+         [    b4_symbol_if([$3], [has_type],
+                           [yy0->b4_symbol($3, slot) = $2 (*yy0, *yy1);],
+                           [*yy0 = $2 (*yy0, *yy1);])])])
+
+
 ## -------------- ##
 ## Declarations.  ##
 ## -------------- ##
@@ -188,7 +197,7 @@ b4_glr_cc_if([],
 [b4_defines_if(
 [b4_output_begin([b4_spec_header_file])
 b4_copyright([Skeleton interface for Bison GLR parsers in C],
-             [2002-2015, 2018-2020])[
+             [2002-2015, 2018-2021])[
 ]b4_cpp_guard_open([b4_spec_mapped_header_file])[
 ]b4_shared_declarations[
 ]b4_cpp_guard_close([b4_spec_mapped_header_file])[
@@ -202,7 +211,7 @@ b4_copyright([Skeleton interface for Bison GLR parsers in C],

 b4_output_begin([b4_parser_file_name])
 b4_copyright([Skeleton implementation for Bison GLR parsers in C],
-             [2002-2015, 2018-2020])[
+             [2002-2015, 2018-2021])[
 /* C GLR parser skeleton written by Paul Hilfinger.  */

 ]b4_disclaimer[
@@ -215,7 +224,7 @@ b4_copyright([Skeleton implementation for Bison GLR parsers in C],
 #define YYLTYPE ]b4_api_PREFIX[LTYPE]])])[
 ]m4_if(b4_prefix, [yy], [],
 [[/* Substitute the variable and function names.  */
-#define yyparse ]b4_prefix[parse
+#define ]b4_glr_cc_if([yy_parse_impl], [yyparse])[ ]b4_prefix[]b4_glr_cc_if([_parse_impl], [parse])[
 #define yylex   ]b4_prefix[lex
 #define yyerror ]b4_prefix[error
 #define yydebug ]b4_prefix[debug]]b4_pure_if([], [[
@@ -875,7 +884,7 @@ yyuserAction (yyRuleNum yyn, int yyrhslen, yyGLRStackItem* yyvsp,
  yybool yynormal YY_ATTRIBUTE_UNUSED = yystackp->yysplitPoint == YY_NULLPTR;
  int yylow;
 ]b4_parse_param_use([yyvalp], [yylocp])dnl
-[  YYUSE (yyrhslen);
+[  YY_USE (yyrhslen);
 # undef yyerrok
 # define yyerrok (yystackp->yyerrState = 0)
 # undef YYACCEPT
@@ -939,8 +948,8 @@ yyuserAction (yyRuleNum yyn, int yyrhslen, yyGLRStackItem* yyvsp,
 static void
 yyuserMerge (int yyn, YYSTYPE* yy0, YYSTYPE* yy1)
 {
-  YYUSE (yy0);
-  YYUSE (yy1);
+  YY_USE (yy0);
+  YY_USE (yy1);

  switch (yyn)
    {
@@ -1795,8 +1804,8 @@ static YYRESULTTAG
 yyreportAmbiguity (yySemanticOption* yyx0,
                   yySemanticOption* yyx1]b4_pure_formals[)
 {
-  YYUSE (yyx0);
-  YYUSE (yyx1);
+  YY_USE (yyx0);
+  YY_USE (yyx1);

 #if ]b4_api_PREFIX[DEBUG
  YY_FPRINTF ((stderr, "Ambiguity detected.\n"));
@@ -2140,7 +2149,7 @@ yypcontext_token (const yyGLRStack *yystackp) YY_ATTRIBUTE_UNUSED;
 static yysymbol_kind_t
 yypcontext_token (const yyGLRStack *yystackp)
 {
-  YYUSE (yystackp);
+  YY_USE (yystackp);
  yysymbol_kind_t yytoken = yychar == ]b4_symbol(-2, id)[ ? ]b4_symbol(-2, kind)[ : YYTRANSLATE (yychar);
  return yytoken;
 }
@@ -2152,7 +2161,7 @@ yypcontext_location (const yyGLRStack *yystackp) YY_ATTRIBUTE_UNUSED;
 static YYLTYPE *
 yypcontext_location (const yyGLRStack *yystackp)
 {
-  YYUSE (yystackp);
+  YY_USE (yystackp);
  return &yylloc;
 }]])],
         [detailed\|verbose],
@@ -2420,7 +2429,7 @@ yyrecoverSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
 `----------*/

 int
-yyparse (]m4_ifset([b4_parse_param], [b4_formals(b4_parse_param)], [void])[)
+]b4_glr_cc_if([yy_parse_impl], [yyparse])[ (]m4_ifset([b4_parse_param], [b4_formals(b4_parse_param)], [void])[)
 {
  int yyresult;
  yyGLRStack yystack;
@@ -1,6 +1,6 @@
 # C++ GLR skeleton for Bison

-# Copyright (C) 2002-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2002-2015, 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.


 # This skeleton produces a C++ class that encapsulates a C glr parser.
@@ -144,7 +144,7 @@ m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
  int
  ]b4_parser_class[::parse ()
  {
-    return ::yyparse (*this]b4_user_args[);
+    return ::yy_parse_impl (*this]b4_user_args[);
  }

 #if ]b4_api_PREFIX[DEBUG
@@ -157,11 +157,11 @@ m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
                           const semantic_type* yyvaluep]b4_locations_if([[,
                           const location_type* yylocationp]])[) const
  {]b4_locations_if([[
-    YYUSE (yylocationp);]])[
-    YYUSE (yyvaluep);
+    YY_USE (yylocationp);]])[
+    YY_USE (yyvaluep);
    std::ostream& yyo = debug_stream ();
    std::ostream& yyoutput = yyo;
-    YYUSE (yyoutput);
+    YY_USE (yyoutput);
    ]b4_symbol_actions([printer])[
  }

@@ -172,7 +172,7 @@ m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
                           const location_type* yylocationp]])[) const
  {
    *yycdebug_ << (yykind < YYNTOKENS ? "token" : "nterm")
-               << ' ' << yytname[yykind] << " ("]b4_locations_if([[
+               << ' ' << yysymbol_name (yykind) << " ("]b4_locations_if([[
               << *yylocationp << ": "]])[;
    yy_symbol_value_print_ (yykind, yyvaluep]b4_locations_if([[, yylocationp]])[);
    *yycdebug_ << ')';
@@ -381,7 +381,7 @@ b4_percent_code_get([[requires]])[
 ]b4_defines_if(
 [b4_output_begin([b4_spec_header_file])
 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
-             [2002-2015, 2018-2020])[
+             [2002-2015, 2018-2021])[
 // C++ GLR parser skeleton written by Akim Demaille.

 ]b4_disclaimer[
@@ -2,7 +2,7 @@

 # Java skeleton dispatching for Bison.

-# Copyright (C) 2007, 2009-2015, 2018-2020 Free Software Foundation,
+# Copyright (C) 2007, 2009-2015, 2018-2021 Free Software Foundation,
 # Inc.

 # This program is free software: you can redistribute it and/or modify
@@ -16,7 +16,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 b4_glr_if(             [b4_complain([%%glr-parser not supported for Java])])
 b4_nondeterministic_if([b4_complain([%%nondeterministic-parser not supported for Java])])
@@ -2,7 +2,7 @@

 # Java language support for Bison

-# Copyright (C) 2007-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2007-2015, 2018-2021 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
@@ -15,7 +15,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 m4_include(b4_skeletonsdir/[c-like.m4])

@@ -71,12 +71,12 @@ m4_define([b4_lexer_if],
 # b4_identification
 # -----------------
 m4_define([b4_identification],
-[  /** Version number for the Bison executable that generated this parser.  */
-  public static final String bisonVersion = "b4_version";
+[[  /** Version number for the Bison executable that generated this parser.  */
+  public static final String bisonVersion = "]b4_version_string[";

  /** Name of the skeleton that generated this parser.  */
-  public static final String bisonSkeleton = b4_skeleton;
-])
+  public static final String bisonSkeleton = ]b4_skeleton[;
+]])


 ## ------------ ##
@@ -1,6 +1,6 @@
 # C++ skeleton for Bison

-# Copyright (C) 2002-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2002-2015, 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 m4_include(b4_skeletonsdir/[c++.m4])

@@ -160,7 +160,7 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))])])


 m4_pushdef([b4_copyright_years],
-           [2002-2015, 2018-2020])
+           [2002-2015, 2018-2021])

 m4_define([b4_parser_class],
          [b4_percent_define_get([[api.parser.class]])])
@@ -271,9 +271,9 @@ m4_define([b4_shared_declarations],
    {
    public:
      context (const ]b4_parser_class[& yyparser, const symbol_type& yyla);
-      const symbol_type& lookahead () const { return yyla_; }
-      symbol_kind_type token () const { return yyla_.kind (); }]b4_locations_if([[
-      const location_type& location () const { return yyla_.location; }
+      const symbol_type& lookahead () const YY_NOEXCEPT { return yyla_; }
+      symbol_kind_type token () const YY_NOEXCEPT { return yyla_.kind (); }]b4_locations_if([[
+      const location_type& location () const YY_NOEXCEPT { return yyla_.location; }
 ]])[
      /// Put in YYARG at most YYARGN of the expected tokens, and return the
      /// number of tokens stored in YYARG.  If YYARG is null, return the
@@ -597,7 +597,7 @@ m4_if(b4_prefix, [yy], [],
 #else // !]b4_api_PREFIX[DEBUG

 # define YYCDEBUG if (false) std::cerr
-# define YY_SYMBOL_PRINT(Title, Symbol)  YYUSE (Symbol)
+# define YY_SYMBOL_PRINT(Title, Symbol)  YY_USE (Symbol)
 # define YY_REDUCE_PRINT(Rule)           static_cast<void> (0)
 # define YY_STACK_PRINT()                static_cast<void> (0)

@@ -736,7 +736,7 @@ m4_if(b4_prefix, [yy], [],
  ]b4_parser_class[::yy_print_ (std::ostream& yyo, const basic_symbol<Base>& yysym) const
  {
    std::ostream& yyoutput = yyo;
-    YYUSE (yyoutput);
+    YY_USE (yyoutput);
    if (yysym.empty ())
      yyo << "empty symbol";
    else
@@ -1,6 +1,6 @@
 # D skeleton for Bison -*- autoconf -*-

-# Copyright (C) 2007-2012, 2019-2020 Free Software Foundation, Inc.
+# Copyright (C) 2007-2012, 2019-2021 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
@@ -13,14 +13,14 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 m4_include(b4_skeletonsdir/[d.m4])


 b4_output_begin([b4_parser_file_name])
 b4_copyright([Skeleton implementation for Bison LALR(1) parsers in D],
-             [2007-2012, 2019-2020])[
+             [2007-2012, 2019-2021])[
 ]b4_disclaimer[
 ]b4_percent_define_ifdef([package], [module b4_percent_define_get([package]);
 ])[
@@ -1,6 +1,6 @@
 # Java skeleton for Bison                           -*- autoconf -*-

-# Copyright (C) 2007-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2007-2015, 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 m4_include(b4_skeletonsdir/[java.m4])

@@ -78,7 +78,7 @@ m4_define([b4_define_state],[[

 ]b4_output_begin([b4_parser_file_name])[
 ]b4_copyright([Skeleton implementation for Bison LALR(1) parsers in Java],
-              [2007-2015, 2018-2020])[
+              [2007-2015, 2018-2021])[
 ]b4_disclaimer[
 ]b4_percent_define_ifdef([api.package], [package b4_percent_define_get([api.package]);[
 ]])[
@@ -1,6 +1,6 @@
 # C++ skeleton for Bison

-# Copyright (C) 2002-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2002-2015, 2018-2021 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
@@ -13,16 +13,16 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 m4_pushdef([b4_copyright_years],
-           [2002-2015, 2018-2020])
+           [2002-2015, 2018-2021])


 # b4_position_file
 # ----------------
 # Name of the file containing the position class, if we want this file.
-b4_defines_if([b4_required_version_if([302], [],
+b4_defines_if([b4_required_version_if([30200], [],
                                      [m4_define([b4_position_file], [position.hh])])])])


@@ -1,6 +1,6 @@
 # C++ skeleton for Bison

-# Copyright (C) 2002-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2002-2015, 2018-2021 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
@@ -13,13 +13,13 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.


 # b4_stack_file
 # -------------
 # Name of the file containing the stack class, if we want this file.
-b4_defines_if([b4_required_version_if([302], [],
+b4_defines_if([b4_required_version_if([30200], [],
                                      [m4_define([b4_stack_file], [stack.hh])])])


@@ -1,6 +1,6 @@
 # C++ skeleton for Bison

-# Copyright (C) 2002-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2002-2015, 2018-2021 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
@@ -13,13 +13,20 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.


 ## --------- ##
 ## variant.  ##
 ## --------- ##

+# b4_assert
+# ---------
+# The name of YY_ASSERT.
+m4_define([b4_assert],
+          [b4_api_PREFIX[]_ASSERT])
+
+
 # b4_symbol_variant(YYTYPE, YYVAL, ACTION, [ARGS])
 # ------------------------------------------------
 # Run some ACTION ("build", or "destroy") on YYVAL of symbol type
@@ -71,12 +78,12 @@ m4_map([      b4_symbol_tag_comment], [$@])dnl
 # -------------------
 # The needed includes for variants support.
 m4_define([b4_variant_includes],
-[b4_parse_assert_if([[#include <typeinfo>]])[
-#ifndef YY_ASSERT
+[b4_parse_assert_if([[#include <typeinfo>
+#ifndef ]b4_assert[
 # include <cassert>
-# define YY_ASSERT assert
+# define ]b4_assert[ assert
 #endif
-]])
+]])])



@@ -110,8 +117,8 @@ m4_define([b4_value_type_declare],
    template <typename T>
    semantic_type (YY_RVREF (T) t)]b4_parse_assert_if([
      : yytypeid_ (&typeid (T))])[
-    {
-      YY_ASSERT (sizeof (T) <= size);
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (sizeof (T) <= size);]])[
      new (yyas_<T> ()) T (YY_MOVE (t));
    }

@@ -125,7 +132,7 @@ m4_define([b4_value_type_declare],
    /// Destruction, allowed only if empty.
    ~semantic_type () YY_NOEXCEPT
    {]b4_parse_assert_if([
-      YY_ASSERT (!yytypeid_);
+      ]b4_assert[ (!yytypeid_);
    ])[}

 # if 201103L <= YY_CPLUSPLUS
@@ -133,10 +140,10 @@ m4_define([b4_value_type_declare],
    template <typename T, typename... U>
    T&
    emplace (U&&... u)
-    {]b4_parse_assert_if([
-      YY_ASSERT (!yytypeid_);
-      YY_ASSERT (sizeof (T) <= size);
-      yytypeid_ = & typeid (T);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (!yytypeid_);
+      ]b4_assert[ (sizeof (T) <= size);
+      yytypeid_ = & typeid (T);]])[
      return *new (yyas_<T> ()) T (std::forward <U>(u)...);
    }
 # else
@@ -144,10 +151,10 @@ m4_define([b4_value_type_declare],
    template <typename T>
    T&
    emplace ()
-    {]b4_parse_assert_if([
-      YY_ASSERT (!yytypeid_);
-      YY_ASSERT (sizeof (T) <= size);
-      yytypeid_ = & typeid (T);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (!yytypeid_);
+      ]b4_assert[ (sizeof (T) <= size);
+      yytypeid_ = & typeid (T);]])[
      return *new (yyas_<T> ()) T ();
    }

@@ -155,10 +162,10 @@ m4_define([b4_value_type_declare],
    template <typename T>
    T&
    emplace (const T& t)
-    {]b4_parse_assert_if([
-      YY_ASSERT (!yytypeid_);
-      YY_ASSERT (sizeof (T) <= size);
-      yytypeid_ = & typeid (T);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (!yytypeid_);
+      ]b4_assert[ (sizeof (T) <= size);
+      yytypeid_ = & typeid (T);]])[
      return *new (yyas_<T> ()) T (t);
    }
 # endif
@@ -185,10 +192,10 @@ m4_define([b4_value_type_declare],
    template <typename T>
    T&
    as () YY_NOEXCEPT
-    {]b4_parse_assert_if([
-      YY_ASSERT (yytypeid_);
-      YY_ASSERT (*yytypeid_ == typeid (T));
-      YY_ASSERT (sizeof (T) <= size);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (yytypeid_);
+      ]b4_assert[ (*yytypeid_ == typeid (T));
+      ]b4_assert[ (sizeof (T) <= size);]])[
      return *yyas_<T> ();
    }

@@ -196,10 +203,10 @@ m4_define([b4_value_type_declare],
    template <typename T>
    const T&
    as () const YY_NOEXCEPT
-    {]b4_parse_assert_if([
-      YY_ASSERT (yytypeid_);
-      YY_ASSERT (*yytypeid_ == typeid (T));
-      YY_ASSERT (sizeof (T) <= size);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (yytypeid_);
+      ]b4_assert[ (*yytypeid_ == typeid (T));
+      ]b4_assert[ (sizeof (T) <= size);]])[
      return *yyas_<T> ();
    }

@@ -214,9 +221,9 @@ m4_define([b4_value_type_declare],
    template <typename T>
    void
    swap (self_type& that) YY_NOEXCEPT
-    {]b4_parse_assert_if([
-      YY_ASSERT (yytypeid_);
-      YY_ASSERT (*yytypeid_ == *that.yytypeid_);])[
+    {]b4_parse_assert_if([[
+      ]b4_assert[ (yytypeid_);
+      ]b4_assert[ (*yytypeid_ == *that.yytypeid_);]])[
      std::swap (as<T> (), that.as<T> ());
    }

@@ -388,11 +395,67 @@ m4_define([_b4_token_maker_define],
 ])])


-m4_define([_b4_type_clause],
-[b4_symbol_if([$1], [is_token],
-              [b4_symbol_if([$1], [has_id],
-                            [tok == token::b4_symbol([$1], [id])],
-                            [tok == b4_symbol([$1], [code])])])])
+# b4_token_kind(SYMBOL-NUM)
+# -------------------------
+# Some tokens don't have an ID.
+m4_define([b4_token_kind],
+[b4_symbol_if([$1], [has_id],
+              [token::b4_symbol([$1], [id])],
+              [b4_symbol([$1], [code])])])
+
+
+# _b4_tok_in(SYMBOL-NUM, ...)
+# ---------------------------
+# See b4_tok_in below.  The SYMBOL-NUMs... are tokens only.
+#
+# We iterate over the tokens to group them by "range" of token numbers (not
+# symbols numbers!).
+#
+# b4_fst is the start of that range.
+# b4_prev is the previous value.
+# b4_val is the current value.
+# If b4_val is the successor of b4_prev in token numbers, update the latter,
+#   otherwise emit the code for range b4_fst .. b4_prev.
+# $1 is also used as a terminator in the foreach, but it will not be printed.
+#
+m4_define([_b4_tok_in],
+[m4_pushdef([b4_prev], [$1])dnl
+m4_pushdef([b4_fst], [$1])dnl
+m4_pushdef([b4_sep], [])dnl
+m4_foreach([b4_val], m4_dquote(m4_shift($@, $1)),
+           [m4_if(b4_symbol(b4_val, [code]), m4_eval(b4_symbol(b4_prev, [code]) + 1), [],
+                  [b4_sep[]m4_if(b4_fst, b4_prev,
+                         [tok == b4_token_kind(b4_fst)],
+                         [(b4_token_kind(b4_fst) <= tok && tok <= b4_token_kind(b4_prev))])[]dnl
+m4_define([b4_fst], b4_val)dnl
+m4_define([b4_sep], [
+                   || ])])dnl
+m4_define([b4_prev], b4_val)])dnl
+m4_popdef([b4_sep])dnl
+m4_popdef([b4_fst])dnl
+m4_popdef([b4_prev])dnl
+])
+
+
+# _b4_filter_tokens(SYMBOL-NUM, ...)
+# ----------------------------------
+# Expand as the list of tokens amongst SYMBOL-NUM.
+m4_define([_b4_filter_tokens],
+[m4_pushdef([b4_sep])dnl
+m4_foreach([b4_val], [$@],
+           [b4_symbol_if(b4_val, [is_token], [b4_sep[]b4_val[]m4_define([b4_sep], [,])])])dnl
+m4_popdef([b4_sep])dnl
+])
+
+
+# b4_tok_in(SYMBOL-NUM, ...)
+# ---------------------------
+# A C++ conditional that checks that `tok` is a member of this list of symbol
+# numbers.
+m4_define([b4_tok_in],
+          [_$0(_b4_filter_tokens($@))])
+
+


 # _b4_token_constructor_define(SYMBOL-NUM...)
@@ -410,9 +473,6 @@ m4_define([_b4_token_constructor_define],
        : super_type(]b4_join([token_type (tok)],
                              b4_symbol_if([$1], [has_type], [std::move (v)]),
                              b4_locations_if([std::move (l)]))[)
-      {
-        YY_ASSERT (]m4_join([ || ], m4_map_sep([_b4_type_clause], [, ], [$@]))[);
-      }
 #else
      symbol_type (]b4_join(
          [int tok],
@@ -422,10 +482,10 @@ m4_define([_b4_token_constructor_define],
        : super_type(]b4_join([token_type (tok)],
                              b4_symbol_if([$1], [has_type], [v]),
                              b4_locations_if([l]))[)
-      {
-        YY_ASSERT (]m4_join([ || ], m4_map_sep([_b4_type_clause], [, ], [$@]))[);
-      }
 #endif
+      {]b4_parse_assert_if([[
+        ]b4_assert[ (]b4_tok_in($@)[);
+      ]])[}
 ]])])


@@ -1,11 +1,11 @@
 #                                                            -*- C -*-
 # Yacc compatible skeleton for Bison

-# Copyright (C) 1984, 1989-1990, 2000-2015, 2018-2020 Free Software
+# Copyright (C) 1984, 1989-1990, 2000-2015, 2018-2021 Free Software
 # Foundation, Inc.

 m4_pushdef([b4_copyright_years],
-           [1984, 1989-1990, 2000-2015, 2018-2020])
+           [1984, 1989-1990, 2000-2015, 2018-2021])

 # 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
@@ -18,7 +18,7 @@ m4_pushdef([b4_copyright_years],
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 m4_include(b4_skeletonsdir/[c.m4])

@@ -1486,7 +1486,7 @@ yypstate_new (void)
  yypstate *yyps;]b4_pure_if([], [[
  if (yypstate_allocated)
    return YY_NULLPTR;]])[
-  yyps = YY_CAST (yypstate *, malloc (sizeof *yyps));
+  yyps = YY_CAST (yypstate *, YYMALLOC (sizeof *yyps));
  if (!yyps)
    return YY_NULLPTR;]b4_pure_if([], [[
  yypstate_allocated = 1;]])[
@@ -1515,7 +1515,7 @@ yypstate_delete (yypstate *yyps)
 #endif]b4_lac_if([[
      if (yyes != yyesa)
        YYSTACK_FREE (yyes);]])[
-      free (yyps);]b4_pure_if([], [[
+      YYFREE (yyps);]b4_pure_if([], [[
      yypstate_allocated = 0;]])[
    }
 }
@@ -1573,14 +1573,16 @@ yyparse (]m4_ifset([b4_parse_param], [b4_formals(b4_parse_param)], [void])[)]])[

  switch (yyps->yynew)
    {
-    case 2:
-      yypstate_clear (yyps);
-      goto case_0;
-
-    case_0:
    case 0:
      yyn = yypact[yystate];
      goto yyread_pushed_token;
+
+    case 2:
+      yypstate_clear (yyps);
+      break;
+
+    default:
+      break;
    }]])[

  YYDPRINTF ((stderr, "Starting parse\n"));
@@ -3,7 +3,7 @@
 <!--
    bison.xsl - common templates for Bison XSLT.

-    Copyright (C) 2007-2015, 2018-2020 Free Software Foundation, Inc.
+    Copyright (C) 2007-2015, 2018-2021 Free Software Foundation, Inc.

    This file is part of Bison, the GNU Compiler Compiler.

@@ -18,12 +18,12 @@
    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 <http://www.gnu.org/licenses/>.
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
  -->

 <xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
-  xmlns:bison="http://www.gnu.org/software/bison/">
+  xmlns:bison="https://www.gnu.org/software/bison/">

 <xsl:key
  name="bison:symbolByName"
@@ -3,7 +3,7 @@
 <!--
    xml2dot.xsl - transform Bison XML Report into DOT.

-    Copyright (C) 2007-2015, 2018-2020 Free Software Foundation, Inc.
+    Copyright (C) 2007-2015, 2018-2021 Free Software Foundation, Inc.

    This file is part of Bison, the GNU Compiler Compiler.

@@ -18,14 +18,14 @@
    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 <http://www.gnu.org/licenses/>.
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.

    Written by Wojciech Polak <polak@gnu.org>.
  -->

 <xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
-  xmlns:bison="http://www.gnu.org/software/bison/">
+  xmlns:bison="https://www.gnu.org/software/bison/">

 <xsl:import href="bison.xsl"/>
 <xsl:output method="text" encoding="UTF-8" indent="no"/>
@@ -3,7 +3,7 @@
 <!--
    xml2text.xsl - transform Bison XML Report into plain text.

-    Copyright (C) 2007-2015, 2018-2020 Free Software Foundation, Inc.
+    Copyright (C) 2007-2015, 2018-2021 Free Software Foundation, Inc.

    This file is part of Bison, the GNU Compiler Compiler.

@@ -18,14 +18,14 @@
    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 <http://www.gnu.org/licenses/>.
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.

    Written by Wojciech Polak <polak@gnu.org>.
  -->

 <xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
-  xmlns:bison="http://www.gnu.org/software/bison/">
+  xmlns:bison="https://www.gnu.org/software/bison/">

 <xsl:import href="bison.xsl"/>
 <xsl:output method="text" encoding="UTF-8" indent="no"/>
@@ -3,7 +3,7 @@
 <!--
    xml2html.xsl - transform Bison XML Report into XHTML.

-    Copyright (C) 2007-2015, 2018-2020 Free Software Foundation, Inc.
+    Copyright (C) 2007-2015, 2018-2021 Free Software Foundation, Inc.

    This file is part of Bison, the GNU Compiler Compiler.

@@ -18,7 +18,7 @@
    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 <http://www.gnu.org/licenses/>.
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.

    Written by Wojciech Polak <polak@gnu.org>.
  -->
@@ -26,7 +26,7 @@
 <xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns="http://www.w3.org/1999/xhtml"
-  xmlns:bison="http://www.gnu.org/software/bison/">
+  xmlns:bison="https://www.gnu.org/software/bison/">

 <xsl:import href="bison.xsl"/>

@@ -88,7 +88,7 @@
      <xsl:apply-templates select="bison-xml-report"/>
      <xsl:text>&#10;&#10;</xsl:text>
      <div id="footer"><hr />This document was generated using
-      <a href="http://www.gnu.org/software/bison/" title="GNU Bison">
+      <a href="https://www.gnu.org/software/bison/" title="GNU Bison">
      GNU Bison <xsl:value-of select="/bison-xml-report/@version"/></a>
      XML Automaton Report.<br />
      <!-- default copying notice -->
@@ -1533,8 +1533,8 @@ FORMULA_MACROFILE      =
 USE_MATHJAX            = NO

 # When MathJax is enabled you can set the default output format to be used for
-# the MathJax output. See the MathJax site (see:
-# http://docs.mathjax.org/en/latest/output.html) for more details.
+# the MathJax output. See the MathJax site
+# <https://docs.mathjax.org/en/latest/> for more details.
 # Possible values are: HTML-CSS (which is slower, but has the best
 # compatibility), NativeMML (i.e. MathML) and SVG.
 # The default value is: HTML-CSS.
@@ -1564,7 +1564,7 @@ MATHJAX_EXTENSIONS     =

 # The MATHJAX_CODEFILE tag can be used to specify a file with javascript pieces
 # of code that will be used on startup of the MathJax code. See the MathJax site
-# (see: http://docs.mathjax.org/en/latest/output.html) for more details. For an
+# <https://docs.mathjax.org/en/latest/> for more details. For an
 # example see the documentation.
 # This tag requires that the tag USE_MATHJAX is set to YES.

@@ -2222,9 +2222,9 @@ HIDE_UNDOC_RELATIONS   = YES

 # If you set the HAVE_DOT tag to YES then doxygen will assume the dot tool is
 # available from the path. This tool is part of Graphviz (see:
-# http://www.graphviz.org/), a graph visualization toolkit from AT&T and Lucent
-# Bell Labs. The other options in this section have no effect if this option is
-# set to NO
+# https://www.graphviz.org/), a graph visualization toolkit from AT&T
+# and Lucent Bell Labs. The other options in this section have no
+# effect if this option is set to NO
 # The default value is: NO.

 HAVE_DOT               = YES
@@ -2377,7 +2377,7 @@ DIRECTORY_GRAPH        = YES
 # The DOT_IMAGE_FORMAT tag can be used to set the image format of the images
 # generated by dot. For an explanation of the image formats see the section
 # output formats in the documentation of the dot tool (Graphviz (see:
-# http://www.graphviz.org/)).
+# https://www.graphviz.org/)).
 # Note: If you choose svg you need to set HTML_FILE_EXTENSION to xhtml in order
 # to make the SVG files visible in IE 9+ (other browsers do not have this
 # requirement).
@@ -173,7 +173,7 @@
 This manual (@value{UPDATED}) is for GNU Bison (version @value{VERSION}),
 the GNU parser generator.

-Copyright @copyright{} 1988--1993, 1995, 1998--2015, 2018--2020 Free
+Copyright @copyright{} 1988--1993, 1995, 1998--2015, 2018--2021 Free
 Software Foundation, Inc.

@quotation
@@ -244,6 +244,7 @@ Reference sections:
 * Invocation::          How to run Bison (to produce the parser implementation).
 * Other Languages::     Creating C++ and Java parsers.
 * History::             How Bison came to be
+* Versioning::          Dealing with Bison versioning
 * FAQ::                 Frequently Asked Questions
 * Table of Symbols::    All the keywords of the Bison language are explained.
 * Glossary::            Basic concepts are explained.
@@ -303,7 +304,7 @@ Grammar Rules for @code{rpcalc}

 * Rpcalc Input::            Explanation of the @code{input} nonterminal
 * Rpcalc Line::             Explanation of the @code{line} nonterminal
-* Rpcalc Expr::             Explanation of the @code{expr} nonterminal
+* Rpcalc Exp::              Explanation of the @code{exp} nonterminal

 Location Tracking Calculator: @code{ltcalc}

@@ -540,6 +541,10 @@ A Brief History of the Greater Ungulates
 * Bison::                       This program
 * Other Ungulates::             Similar programs

+Bison Version Compatibility
+
+* Versioning::                  Dealing with Bison versioning
+
 Frequently Asked Questions

 * Memory Exhausted::            Breaking the Stack Limits
@@ -1663,7 +1668,7 @@ after @samp{//}.
@example
 /* Parser for rpcalc.   -*- C -*-

-   Copyright (C) 1988-1993, 1995, 1998-2015, 2018-2020 Free Software
+   Copyright (C) 1988-1993, 1995, 1998-2015, 2018-2021 Free Software
   Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.
@@ -1679,7 +1684,7 @@ after @samp{//}.
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
@end example
@end ignore

@@ -1788,7 +1793,7 @@ rule are referred to as @code{$1}, @code{$2}, and so on.
@menu
 * Rpcalc Input::            Explanation of the @code{input} nonterminal
 * Rpcalc Line::             Explanation of the @code{line} nonterminal
-* Rpcalc Expr::             Explanation of the @code{expr} nonterminal
+* Rpcalc Exp::              Explanation of the @code{exp} nonterminal
@end menu

@node Rpcalc Input
@@ -1853,8 +1858,8 @@ uninitialized (its value will be unpredictable).  This would be a bug if
 that value were ever used, but we don't use it: once rpcalc has printed the
 value of the user's input line, that value is no longer needed.

-@node Rpcalc Expr
-@subsubsection Explanation of @code{expr}
+@node Rpcalc Exp
+@subsubsection Explanation of @code{exp}

 The @code{exp} grouping has several rules, one for each kind of expression.
 The first rule handles the simplest expressions: those that are just
@@ -2549,7 +2554,7 @@ Here are the C and Bison declarations for the multi-function calculator.
@example
 /* Parser for mfcalc.   -*- C -*-

-   Copyright (C) 1988-1993, 1995, 1998-2015, 2018-2020 Free Software
+   Copyright (C) 1988-1993, 1995, 1998-2015, 2018-2021 Free Software
   Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.
@@ -2565,7 +2570,7 @@ Here are the C and Bison declarations for the multi-function calculator.
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
@end example
@end ignore

@@ -2678,7 +2683,7 @@ provides for either functions or variables to be placed in the table.
@example
 /* Functions for mfcalc.   -*- C -*-

-   Copyright (C) 1988-1993, 1995, 1998-2015, 2018-2020 Free Software
+   Copyright (C) 1988-1993, 1995, 1998-2015, 2018-2021 Free Software
   Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.
@@ -2694,7 +2699,7 @@ provides for either functions or variables to be placed in the table.
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
@end example
@end ignore

@@ -6296,7 +6301,10 @@ Introduced in Bison 3.3 to replace @code{parser_class_name}.

@item Default Value: @code{YY} for Java, @code{yy} otherwise.

-@item History: introduced in Bison 2.6
+@item History:
+introduced in Bison 2.6, with its argument in double quotes.  Uses braces
+since Bison 3.0 (double quotes are still supported for backward
+compatibility).
@end itemize
@end deffn

@@ -7805,7 +7813,7 @@ static int
 yyreport_syntax_error (const yypcontext_t *ctx)
@{
  int res = 0;
-  YY_LOCATION_PRINT (stderr, *yypcontext_location (ctx));
+  location_print (stderr, yypcontext_location (ctx));
  fprintf (stderr, ": syntax error");
  // Report the tokens expected at this point.
  @{
@@ -9942,10 +9950,11 @@ very documentation.  To solve a conflict, one must understand it: when does
 it occur?  Is it because of a flaw in the grammar?  Is it rather because
 LR(1) cannot cope with this grammar?

-On difficulty is that conflicts occur in the @emph{automaton}, and it can be
-tricky to related them to issues in the @emph{grammar} itself.  With
-experience and patience, analysis the detailed description of the automaton
-(@pxref{Understanding}) allows to find example strings that reach these conflicts.
+One difficulty is that conflicts occur in the @emph{automaton}, and it can
+be tricky to relate them to issues in the @emph{grammar} itself.  With
+experience and patience, analysis of the detailed description of the
+automaton (@pxref{Understanding}) allows one to find example strings that
+reach these conflicts.

 That task is made much easier thanks to the generation of counterexamples,
 initially developed by Chinawat Isradisaikul and Andrew Myers
@@ -10098,7 +10107,7 @@ sequence.y:8.3-45: @dwarning{warning}: rule useless in parser due to conflicts [

 Each of these three conflicts, again, prove that the grammar is ambiguous.
 For instance, the second conflict (the reduce/reduce one) shows that the
-grammar accept the empty input in two different ways.
+grammar accepts the empty input in two different ways.

@sp 1

@@ -11865,8 +11874,8 @@ described under the @option{-v} and @option{-d} options.
@item -g [@var{file}]
@itemx --graph[=@var{file}]
 Output a graphical representation of the parser's automaton computed by
-Bison, in @uref{http://www.graphviz.org/, Graphviz}
-@uref{http://www.graphviz.org/doc/info/lang.html, DOT} format.
+Bison, in @uref{https://www.graphviz.org/, Graphviz}
+@uref{https://www.graphviz.org/doc/info/lang.html, DOT} format.
@code{@var{file}} is optional.  If omitted and the grammar file is
@file{foo.y}, the output file will be @file{foo.gv} if the @code{%required}
 version is 3.4 or better, @file{foo.dot} otherwise.
@@ -11984,7 +11993,7 @@ generate C++.
@example
 /* Simple variant-based parser.   -*- C++ -*-

-   Copyright (C) 2018-2020 Free Software Foundation, Inc.
+   Copyright (C) 2018-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -11999,7 +12008,7 @@ generate C++.
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
@end example
@end ignore

@@ -13080,7 +13089,7 @@ library components, and the declaration of the parser class.
@example
 /* Driver for calc++.   -*- C++ -*-

-   Copyright (C) 2005--2015, 2018--2020 Free Software Foundation, Inc.
+   Copyright (C) 2005-2015, 2018-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -13095,7 +13104,7 @@ library components, and the declaration of the parser class.
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
@end example
@end ignore

@@ -13176,7 +13185,7 @@ The implementation of the driver (@file{driver.cc}) is straightforward.
@example
 /* Driver for calc++.   -*- C++ -*-

-   Copyright (C) 2005--2015, 2018--2020 Free Software Foundation, Inc.
+   Copyright (C) 2005-2015, 2018-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -13191,7 +13200,7 @@ The implementation of the driver (@file{driver.cc}) is straightforward.
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
@end example
@end ignore

@@ -13243,7 +13252,7 @@ designed the grammar for.
@example
 /* Parser for calc++.   -*- C++ -*-

-   Copyright (C) 2005--2015, 2018--2020 Free Software Foundation, Inc.
+   Copyright (C) 2005-2015, 2018-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -13258,7 +13267,7 @@ designed the grammar for.
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
@end example
@end ignore

@@ -13455,7 +13464,7 @@ then the parser's to get the set of defined tokens.
@example
 /* Scanner for calc++.   -*- C++ -*-

-   Copyright (C) 2005--2015, 2018--2020 Free Software Foundation, Inc.
+   Copyright (C) 2005-2015, 2018-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -13470,7 +13479,7 @@ then the parser's to get the set of defined tokens.
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
@end example
@end ignore

@@ -13551,6 +13560,14 @@ then the parser's to get the set of defined tokens.
 #  pragma GCC diagnostic ignored "-Wsign-conversion"
 # endif
 #endif
+
+// Flex 2.6.4, GCC 9
+// warning: useless cast to type 'int' [-Wuseless-cast]
+// 1361 |   YY_CURRENT_BUFFER_LVALUE->yy_buf_size = (int) (new_size - 2);
+//      |                                                 ^
+#if defined GCC_VERSION && 900 <= GCC_VERSION
+# pragma GCC diagnostic ignored "-Wuseless-cast"
+#endif
 %@}
@end example
@end ignore
@@ -13702,7 +13719,7 @@ The top level file, @file{calc++.cc}, poses no problem.
@example
 /* Main for calc++.   -*- C++ -*-

-   Copyright (C) 2005--2015, 2018--2020 Free Software Foundation, Inc.
+   Copyright (C) 2005-2015, 2018-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -13717,7 +13734,7 @@ The top level file, @file{calc++.cc}, poses no problem.
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
@end example
@end ignore

@@ -14559,7 +14576,7 @@ Portable C Compiler, pcc. The same person, Steven C. Johnson, wrote Yacc and
 the original pcc.

 According to the author
-@footnote{@url{https://lists.gnu.org/archive/html/bison-patches/2019-02/msg00061.html}},
+@footnote{@url{https://lists.gnu.org/r/bison-patches/2019-02/msg00061.html}},
 Yacc was first invented in 1971 and reached a form recognizably similar to
 the C version in 1973.  Johnson published @cite{A Portable Compiler: Theory
 and Practice} @pcite{Johnson 1978}.
@@ -14663,6 +14680,66 @@ still in use is David Beazley's ``PLY'' (Python Lex-Yacc) for
 Python. Another is goyacc, supporting the Go language. An ``ocamlyacc''
 is shipped as part of the Ocaml compiler suite.

+@c ================================================= Version Compatibility
+
+@node Versioning
+@chapter Bison Version Compatibility: Best Practices
+@cindex version
+@cindex compatibility
+
+Bison provides a Yacc compatibility mode in which it strives to conform with
+the POSIX standard.  Grammar files which are written to the POSIX standard, and
+do not take advantage of any of the special capabilities of Bison, should
+work with many versions of Bison without modification.
+
+All other features of Bison are particular to Bison, and are changing.  Bison
+is actively maintained and continuously evolving.  It should come as no
+surprise that an older version of Bison will not accept Bison source code which
+uses newer features that do no not exist at all in the older Bison.
+Regrettably, in spite of reasonable effort to maintain compatibility, the
+reverse situation may also occur: it may happen that code developed using an
+older version of Bison does not build with a newer version of Bison without
+modifications.
+
+Because Bison is a code generation tool, it is possible to retain its output
+and distribute that to the users of the program.  The users are then not
+required to have Bison installed at all, only an implementation of the
+programming language, such as C, which is required for processing the generated
+output.
+
+It is the output of Bison that is intended to be of the utmost portability.
+So, that is to say, whereas the Bison grammar source code may have a dependency
+on specific versions of Bison, the generated parser from any version of Bison
+should work with with a large number of implementations of C, or whatever
+language is applicable.
+
+The recommended best practice for using Bison (in the context of software that
+is distributed in source code form) is to ship the generated parser to the
+downstream users.  Only those downstream users who engage in active development
+of the program who need to make changes to the grammar file need to have Bison
+installed at all, and those users can install the specific version of Bison
+which is required.
+
+Following this recommended practice also makes it possible to use a more recent
+Bison than what is available to users through operating system distributions,
+thereby taking advantage of the latest techniques that Bison allows.
+
+Some features of Bison have been, or are being adopted into other Yacc-like
+programs.  Therefore it might seem that is a good idea to write grammar code
+which targets multiple implementations, similarly to the way C programs are
+often written to target multiple compilers and language versions.  Other than
+the Yacc subset described by POSIX, the Bison language is not rigorously
+standardized.  When a Bison feature is adopted by another parser generator, it
+may be initially compatible with that version of Bison on which it was based,
+but the compatibility may degrade going forward.  Developers who strive to make
+their Bison code simultaneously compatible with other parser generators are
+encouraged to nevertheless use specific versions of all generators, and still
+follow the recommended practice of shipping generated output.  For example,
+a project can internally maintain compatibility with multiple generators,
+and choose the output of a particular one to ship to the users.  Or else,
+the project could ship all of the outputs, arranging for a way for the user
+to specify which one is used to build the program.
+
@c ================================================= FAQ

@node FAQ
@@ -15077,7 +15154,7 @@ systems are especially welcome.
 How do I join the help-bison and bug-bison mailing lists?
@end quotation

-See @url{http://lists.gnu.org/}.
+See @url{https://lists.gnu.org/}.

@c ================================================= Table of Symbols

@@ -15430,6 +15507,12 @@ Macro to discard a value from the parser stack and fake a lookahead
 token.  @xref{Action Features}.
@end deffn

+@deffn {Macro} YYBISON
+The version of Bison as an integer, for instance 30704 for version 3.7.4.
+Defined in @file{yacc.c} only.  Before version 3.7.4, @code{YYBISON} was
+defined to 1.
+@end deffn
+
@deffn {Variable} yychar
 External integer variable that contains the integer value of the
 lookahead token.  (In a pure parser, it is a local variable within
@@ -15902,35 +15985,35 @@ Division, University of California, Berkeley, California
@c when
 (June 1985).
@c url
-@uref{http://xtf.lib.berkeley.edu/reports/TRWebData/accessPages/CSD-85-251.html}
+@uref{https://digicoll.lib.berkeley.edu/record/135875}

@anchor{Denny 2008}
@item [Denny 2008]
 Joel E. Denny and Brian A. Malloy, IELR(1): Practical LR(1) Parser Tables
 for Non-LR(1) Grammars with Conflict Resolution, in @cite{Proceedings of the
 2008 ACM Symposium on Applied Computing} (SAC'08), ACM, New York, NY, USA,
-pp.@: 240--245.  @uref{http://dx.doi.org/10.1145/1363686.1363747}
+pp.@: 240--245.  @uref{https://dx.doi.org/10.1145/1363686.1363747}

@anchor{Denny 2010 May}
@item [Denny 2010 May]
 Joel E. Denny, PSLR(1): Pseudo-Scannerless Minimal LR(1) for the
 Deterministic Parsing of Composite Languages, Ph.D. Dissertation, Clemson
 University, Clemson, SC, USA (May 2010).
-@uref{http://proquest.umi.com/pqdlink?did=2041473591&Fmt=7&clientId=79356&RQT=309&VName=PQD}
+@uref{https://tigerprints.clemson.edu/all_dissertations/519/}

@anchor{Denny 2010 November}
@item [Denny 2010 November]
 Joel E. Denny and Brian A. Malloy, The IELR(1) Algorithm for Generating
 Minimal LR(1) Parser Tables for Non-LR(1) Grammars with Conflict Resolution,
 in @cite{Science of Computer Programming}, Vol.@: 75, Issue 11 (November
-2010), pp.@: 943--979.  @uref{http://dx.doi.org/10.1016/j.scico.2009.08.001}
+2010), pp.@: 943--979.  @uref{https://dx.doi.org/10.1016/j.scico.2009.08.001}

@anchor{DeRemer 1982}
@item [DeRemer 1982]
 Frank DeRemer and Thomas Pennello, Efficient Computation of LALR(1)
 Look-Ahead Sets, in @cite{ACM Transactions on Programming Languages and
 Systems}, Vol.@: 4, No.@: 4 (October 1982), pp.@:
-615--649. @uref{http://dx.doi.org/10.1145/69622.357187}
+615--649. @uref{https://dx.doi.org/10.1145/69622.357187}

@anchor{Isradisaikul 2015}
@item [Isradisaikul 2015]
@@ -15954,14 +16037,14 @@ pp.@: 97--104.
@item [Knuth 1965]
 Donald E. Knuth, On the Translation of Languages from Left to Right, in
@cite{Information and Control}, Vol.@: 8, Issue 6 (December 1965), pp.@:
-607--639. @uref{http://dx.doi.org/10.1016/S0019-9958(65)90426-2}
+607--639. @uref{https://dx.doi.org/10.1016/S0019-9958(65)90426-2}

@anchor{Scott 2000}
@item [Scott 2000]
 Elizabeth Scott, Adrian Johnstone, and Shamsa Sadaf Hussain,
@cite{Tomita-Style Generalised LR Parsers}, Royal Holloway, University of
 London, Department of Computer Science, TR-00-12 (December 2000).
-@uref{http://www.cs.rhul.ac.uk/research/languages/publications/tomita_style_1.ps}
+@uref{https://www.cs.rhul.ac.uk/research/languages/publications/tomita_style_1.ps}
@end table

@node Index of Terms
@@ -16049,8 +16132,10 @@ London, Department of Computer Science, TR-00-12 (December 2000).
@c LocalWords: getLocation getExpectedTokens reportSyntaxError bistromathic
@c LocalWords: TokenKind Automake's rtti Wcounterexamples Chinawat PLDI
@c LocalWords: Isradisaikul tcite pcite rgbGreen colorGreen rgbYellow Wcex
-@c LocalWords: colorYellow rgbRed colorRed rgbBlue colorBlue rgbPurple
+@c LocalWords: colorYellow rgbRed colorRed rgbBlue colorBlue rgbPurple Ddoc
@c LocalWords: colorPurple ifhtml ifnothtml situ rcex MERCHANTABILITY Wnone
+@c LocalWords: diagError diagNotice diagWarning diagOff danglingElseCex
+@c LocalWords: YYLocation YYPosition nonunifying

@c Local Variables:
@c ispell-dictionary: "american"
@@ -1,6 +1,6 @@
 // Generated by GNU Bison 2.6.90.
 // Report bugs to <[email protected]>.
-// Home page: <http://www.gnu.org/software/bison/>.
+// Home page: <https://www.gnu.org/software/bison/>.

 digraph "example.y"
 {
@@ -1,4 +1,4 @@
-## Copyright (C) 2001-2003, 2005-2015, 2018-2020 Free Software
+## Copyright (C) 2001-2003, 2005-2015, 2018-2021 Free Software
 ## Foundation, Inc.

 ## This program is free software: you can redistribute it and/or modify
@@ -12,7 +12,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 AM_MAKEINFOFLAGS =                                              \
  --no-split                                                    \
@@ -56,8 +56,8 @@ MAINTAINERCLEANFILES = $(CROSS_OPTIONS_TEXI)


 # Fix Info's @code in @deftype
-# https://lists.gnu.org/archive/html/help-texinfo/2019-11/msg00004.html
-all: $(srcdir)/$(%C%_bison).info.bak
+# https://lists.gnu.org/r/help-texinfo/2019-11/msg00004.html
+all-local: $(srcdir)/$(%C%_bison).info.bak
 $(srcdir)/$(%C%_bison).info.bak: $(srcdir)/$(%C%_bison).info
 	$(AM_V_GEN) $(PERL) -pi.bak -0777	\
 	  -e 's{(^ --.*\n(?: {10}.*\n)*)}'	\
@@ -19,7 +19,7 @@
 \def\finalout{\overfullrule=0pt}
 %\finalout

-% Copyright (c) 1998, 2001, 2009--2015, 2018--2020 Free Software
+% Copyright (c) 1998, 2001, 2009--2015, 2018--2021 Free Software
 % Foundation, Inc.
 %
 % This file is part of Bison.
@@ -35,7 +35,7 @@
 % 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 <http://www.gnu.org/licenses/>.
+% along with this program.  If not, see <https://www.gnu.org/licenses/>.
 %
 % This file is intended to be processed by plain TeX (TeX82).
 %
@@ -22,7 +22,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2006, 2009-2015, 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 2006, 2009-2015, 2018-2021 Free Software Foundation, Inc.

 This file is part of Bison, the GNU Compiler Compiler.

@@ -1,6 +1,6 @@
 #! /usr/bin/perl -w

-# Copyright (C) 2006, 2008-2015, 2018-2020 Free Software Foundation,
+# Copyright (C) 2006, 2008-2015, 2018-2021 Free Software Foundation,
 # Inc.
 #
 # This file is part of Bison, the GNU Compiler Compiler.
@@ -16,7 +16,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 =head1 NAME

@@ -185,13 +185,13 @@ my $verbose = 1;

 =over 4

-=item C<verbose($level, $message)>
+=item C<verbose ($level, $message)>

 Report the C<$message> is C<$level> E<lt>= C<$verbose>.

 =cut

-sub verbose($$)
+sub verbose ($$)
 {
  my ($level, $message) = @_;
  print STDERR $message
@@ -201,13 +201,13 @@ sub verbose($$)

 ######################################################################

-=item C<directives($bench, @directive)>
+=item C<directives ($bench, @directive)>

 Format the list of directives for Bison for bench named C<$bench>.

 =cut

-sub directives($@)
+sub directives ($@)
 {
  my ($bench, @directive) = @_;
  my $res = "/* Directives for bench '$bench'. */\n";
@@ -218,6 +218,27 @@ sub directives($@)

 ######################################################################

+=item C<is_pure (@directive)>
+
+Whether api.pure is set.
+
+=cut
+
+sub is_pure (@)
+{
+  my (@directive) = @_;
+  for my $dir (@directive)
+    {
+      if ($dir =~ /\A%define api.pure/)
+        {
+          return 1;
+        }
+    }
+  return 0;
+}
+
+######################################################################
+
 =item C<generate_grammar_triangular ($base, $max, @directive)>

 Create a large triangular grammar which looks like :
@@ -389,18 +410,14 @@ sub generate_grammar_calc ($$@)
 %define api.value.type union
 $directives

-%{
+%code provides {
 static int power (int base, int exponent);
 /* yyerror receives the location if:
   - %location & %pure & %glr
   - %location & %pure & %yacc & %parse-param. */
 static void yyerror (const char *s);
-#if YYPURE
-static int yylex (YYSTYPE* yylvalp);
-#else
-static int yylex (void);
-#endif
-%}
+static int yylex (@{[is_pure (@directive) ? "YYSTYPE *yylvalp" : "void"]});
+}

 /* Bison Declarations */
 %token
@@ -467,12 +484,7 @@ yyerror (const char *s)
 }

 static int
-#if YYPURE
-# define yylval (*yylvalp)
-yylex (YYSTYPE* yylvalp)
-#else
-yylex (void)
-#endif
+yylex (@{[is_pure (@directive) ? "YYSTYPE *yylvalp" : "void"]})
 {
  int c;

@@ -498,7 +510,7 @@ yylex (void)
    case '5': case '6': case '7': case '8': case '9':
      {
        int nchars = 0;
-        int n = sscanf (input - 1, "%d%n", &yylval.NUM, &nchars);
+        int n = sscanf (input - 1, "%d%n", &@{[is_pure (@directive) ? "yylvalp->" : "yylval."]}NUM, &nchars);
        assert (n == 1);
        input += nchars - 1;
        return NUM;
@@ -506,7 +518,7 @@ yylex (void)

    default:
      yyerror ("error: invalid character");
-      return yylex ();
+      return yylex (@{[is_pure (@directive) ? "yylvalp" : ""]});
    }
 }
 EOF
@@ -592,10 +604,10 @@ $directives
  // Prototype of the yylex function providing subsequent tokens.
  static
 #if USE_TOKEN_CTOR
-  yy::parser::symbol_type yylex();
+  yy::parser::symbol_type yylex ();
 #else
-  yy::parser::token_type yylex(yy::parser::semantic_type* yylvalp,
-                               yy::parser::location_type* yyllocp);
+  yy::parser::token_type yylex (yy::parser::semantic_type *yylvalp,
+                                yy::parser::location_type *yyllocp);
 #endif

  // Conversion to string.
@@ -618,8 +630,8 @@ EOF
      print $out <<'EOF';
 %token <std::string> TEXT
 %token <int> NUMBER
-%printer { std::cerr << "Number: " << $$; } <int>
-%printer { std::cerr << "Text: " << $$; } <std::string>
+%printer { yyo << "Number: " << $$; } <int>
+%printer { yyo << "Text: " << $$; } <std::string>
 %type <std::string> text result

 %%
@@ -641,8 +653,8 @@ EOF
 %union {int ival; std::string* sval;}
 %token <sval> TEXT
 %token <ival> NUMBER
-%printer { std::cerr << "Number: " << $$; } <ival>
-%printer { std::cerr << "Text: " << *$$; } <sval>
+%printer { yyo << "Number: " << $$; } <ival>
+%printer { yyo << "Text: " << *$$; } <sval>
 %type <sval> text result

 %%
@@ -664,10 +676,10 @@ EOF

 static
 #if USE_TOKEN_CTOR
-yy::parser::symbol_type yylex()
+yy::parser::symbol_type yylex ()
 #else
-yy::parser::token_type yylex(yy::parser::semantic_type* yylvalp,
-                             yy::parser::location_type* yyllocp)
+yy::parser::token_type yylex (yy::parser::semantic_type *yylvalp,
+                              yy::parser::location_type *yyllocp)
 #endif
 {
  typedef yy::parser::location_type location_type;
@@ -1060,7 +1072,7 @@ sub help ($)
 {
  my ($verbose) = @_;
  use Pod::Usage;
-  # See <URL:http://perldoc.perl.org/pod2man.html#NOTES>.
+  # See <URL:https://perldoc.perl.org/pod2man.html#NOTES>.
  pod2usage( { -message => "Bench Bison parsers",
               -exitval => 0,
               -verbose => $verbose,
@@ -1,4 +1,4 @@
-## Copyright (C) 2006, 2008-2015, 2018-2020 Free Software Foundation,
+## Copyright (C) 2006, 2008-2015, 2018-2021 Free Software Foundation,
 ## Inc.

 ## This program is free software: you can redistribute it and/or modify
@@ -12,7 +12,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 dist_noinst_DATA = %D%/README.md
 nodist_noinst_SCRIPTS = %D%/bench.pl
@@ -17,7 +17,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 2018-2021 Free Software Foundation, Inc.

 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -46,7 +46,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 2018-2021 Free Software Foundation, Inc.

 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -36,7 +36,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 2018-2021 Free Software Foundation, Inc.

 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -1,6 +1,6 @@
 #! /bin/sh

-# Copyright (C) 2005-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2005-2015, 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 cat >input <<EOF
 toto := 1
@@ -1,4 +1,4 @@
-## Copyright (C) 2005-2006, 2008-2015, 2018-2020 Free Software
+## Copyright (C) 2005-2006, 2008-2015, 2018-2021 Free Software
 ## Foundation, Inc.
 ##
 ## This program is free software: you can redistribute it and/or modify
@@ -12,7 +12,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 ## ------------------- ##
 ## Parser generation.  ##
@@ -1,4 +1,4 @@
-## Copyright (C) 2018-2020 Free Software Foundation, Inc.
+## Copyright (C) 2018-2021 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
@@ -11,7 +11,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 cxxdir = $(docdir)/%D%
 include %D%/calc++/local.mk
@@ -1,6 +1,6 @@
 #! /bin/sh

-# Copyright (C) 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 : >input
 run 0 "{I have numbers for you., 1, 2, 3, And that's all!}" 4
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2008-2015, 2018-2020 Free Software Foundation, Inc.
+  Copyright (C) 2008-2015, 2018-2021 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
@@ -12,7 +12,7 @@
  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 <http://www.gnu.org/licenses/>.
+  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 %require "3.2"
@@ -1,6 +1,6 @@
 #! /bin/sh

-# Copyright (C) 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 : >input
 run 0 "{I have three numbers for you., 1, 2, 3, And that's all!}"
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2008-2015, 2018-2020 Free Software Foundation, Inc.
+  Copyright (C) 2008-2015, 2018-2021 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
@@ -12,7 +12,7 @@
  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 <http://www.gnu.org/licenses/>.
+  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

 %require "3.2"
@@ -81,7 +81,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 2018-2021 Free Software Foundation, Inc.

 This file is part of GNU bison, the GNU Compiler Compiler.

@@ -32,7 +32,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2020 Free Software Foundation, Inc.
+Copyright (C) 2020-2021 Free Software Foundation, Inc.

 This file is part of Bison, the GNU Compiler Compiler.

@@ -1,6 +1,6 @@
 #! /bin/sh

-# Copyright (C) 2020 Free Software Foundation, Inc.
+# Copyright (C) 2020-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 # Users may customize the behavior of readline, which might break our
 # expected results.
@@ -251,29 +251,29 @@ err: Next token is token ) (1.4: )
 err: Shifting token ) (1.4: )
 err: Entering state 20
 err: Stack now 0 2 10 20
-err: Reducing stack by rule 15 (line 151):
+err: Reducing stack by rule XX (line XXX):
 err:    $1 = token ( (1.1: )
 err:    $2 = token error (1.2-3: )
 err:    $3 = token ) (1.4: )
 err: -> $$ = nterm exp (1.1-4: 666)
-err: Entering state 7
-err: Stack now 0 7
+err: Entering state 8
+err: Stack now 0 8
 err: Return for a new token:
 err: Reading a token
 err: Now at end of input.
 err: LAC: initial context established for end of file
-err: LAC: checking lookahead end of file: R2 G8 S19
-err: Reducing stack by rule 2 (line 126):
+err: LAC: checking lookahead end of file: R2 G7 S14
+err: Reducing stack by rule XX (line XXX):
 err:    $1 = nterm exp (1.1-4: 666)
 err: -> $$ = nterm input (1.1-4: )
-err: Entering state 8
-err: Stack now 0 8
+err: Entering state 7
+err: Stack now 0 7
 err: Now at end of input.
 err: Shifting token end of file (1.5: )
 err: LAC: initial context discarded due to shift
-err: Entering state 19
-err: Stack now 0 8 19
-err: Stack now 0 8 19
+err: Entering state 14
+err: Stack now 0 7 14
+err: Stack now 0 7 14
 err: Cleanup: popping token end of file (1.5: )
 err: Cleanup: popping nterm input (1.1-4: )' -p

@@ -1,4 +1,4 @@
-## Copyright (C) 2020 Free Software Foundation, Inc.
+## Copyright (C) 2020-2021 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
@@ -11,7 +11,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 bistromathicdir = $(docdir)/%D%

@@ -1,6 +1,6 @@
 /* Parser and scanner for bistromathic.   -*- C -*-

-   Copyright (C) 2019-2020 Free Software Foundation, Inc.
+   Copyright (C) 2019-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -15,7 +15,7 @@
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

 %require "3.7"

@@ -9,7 +9,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2019-2020 Free Software Foundation, Inc.
+Copyright (C) 2019-2021 Free Software Foundation, Inc.

 This file is part of Bison, the GNU Compiler Compiler.

@@ -1,6 +1,6 @@
 #! /bin/sh

-# Copyright (C) 2019-2020 Free Software Foundation, Inc.
+# Copyright (C) 2019-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 cat >input <<EOF
 1+2*3
@@ -1,4 +1,4 @@
-## Copyright (C) 2019-2020 Free Software Foundation, Inc.
+## Copyright (C) 2019-2021 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
@@ -11,7 +11,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 calcdir = $(docdir)/%D%

@@ -11,7 +11,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 2018-2021 Free Software Foundation, Inc.

 This file is part of Bison, the GNU Compiler Compiler.

@@ -1,6 +1,6 @@
 #! /bin/sh

-# Copyright (C) 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 cat >input <<EOF
 1+2*3
@@ -1,4 +1,4 @@
-## Copyright (C) 2018-2020 Free Software Foundation, Inc.
+## Copyright (C) 2018-2021 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
@@ -11,7 +11,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 lexcalcdir = $(docdir)/%D%

@@ -31,6 +31,13 @@ endif FLEX_WORKS

 %D%/parse.c: $(dependencies)

+# Tell Make scan.o depends on parse.h, except that Make sees only
+# parse.c, not parse.h.  We can't use BUILT_SOURCES to this end, since
+# we use the built bison.
+%D%/lexcalc$(DASH)scan.o: %D%/parse.c
+# Likewise, but for Automake before 1.16.
+%D%/examples_c_lexcalc_lexcalc$(DASH)scan.o: %D%/parse.c
+
 EXTRA_DIST += %D%/lexcalc.test
 dist_lexcalc_DATA = %D%/parse.y %D%/scan.l %D%/Makefile %D%/README.md
 CLEANFILES += %D%/parse.[ch] %D%/scan.c %D%/parse.output
@@ -1,6 +1,6 @@
 /* Parser for lexcalc.   -*- C -*-

-   Copyright (C) 2018-2020 Free Software Foundation, Inc.
+   Copyright (C) 2018-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -15,7 +15,7 @@
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

 // Prologue (directives).
 %expect 0
@@ -1,6 +1,6 @@
 /* Scanner for lexcalc.   -*- C -*-

-   Copyright (C) 2018-2020 Free Software Foundation, Inc.
+   Copyright (C) 2018-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -15,7 +15,7 @@
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

 /* Prologue (directives). */

@@ -1,4 +1,4 @@
-## Copyright (C) 2018-2020 Free Software Foundation, Inc.
+## Copyright (C) 2018-2021 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
@@ -11,7 +11,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 cdir = $(docdir)/%D%
 dist_c_DATA = %D%/README.md
@@ -1,4 +1,4 @@
-## Copyright (C) 2005-2006, 2008-2015, 2018-2020 Free Software
+## Copyright (C) 2005-2006, 2008-2015, 2018-2021 Free Software
 ## Foundation, Inc.
 ##
 ## This program is free software: you can redistribute it and/or modify
@@ -12,7 +12,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 ## -------------------- ##
 ## Building & testing.  ##
@@ -1,6 +1,6 @@
 #! /bin/sh

-# Copyright (C) 2005-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2005-2015, 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 cat >input <<EOF
 1+2*3
@@ -20,7 +20,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2020 Free Software Foundation, Inc.
+Copyright (C) 2020-2021 Free Software Foundation, Inc.

 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -1,6 +1,6 @@
 #! /bin/sh

-# Copyright (C) 2020 Free Software Foundation, Inc.
+# Copyright (C) 2020-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 cat >input <<EOF
 1+2*3
@@ -1,6 +1,6 @@
 /* Parser and scanner for pushcalc.   -*- C -*-

-   Copyright (C) 2020 Free Software Foundation, Inc.
+   Copyright (C) 2020-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -15,7 +15,7 @@
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

 %code top {
  #include <ctype.h>  /* isdigit. */
@@ -1,4 +1,4 @@
-## Copyright (C) 2020 Free Software Foundation, Inc.
+## Copyright (C) 2020-2021 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
@@ -11,7 +11,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 pushcalcdir = $(docdir)/%D%

@@ -26,7 +26,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 2018-2021 Free Software Foundation, Inc.

 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -1,4 +1,4 @@
-## Copyright (C) 2019-2020 Free Software Foundation, Inc.
+## Copyright (C) 2019-2021 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
@@ -11,7 +11,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 reccalcdir = $(docdir)/%D%

@@ -1,6 +1,6 @@
 /* Parser for reccalc.   -*- C -*-

-   Copyright (C) 2019-2020 Free Software Foundation, Inc.
+   Copyright (C) 2019-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -15,7 +15,7 @@
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

 // Prologue (directives).
 %expect 0
@@ -1,6 +1,6 @@
 #! /bin/sh

-# Copyright (C) 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 (seq 0) >/dev/null 2>&1 || skip "gimme one seq"

@@ -1,6 +1,6 @@
 /* Scanner for reccalc.   -*- C -*-

-   Copyright (C) 2019-2020 Free Software Foundation, Inc.
+   Copyright (C) 2019-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -15,7 +15,7 @@
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

 /* Prologue (directives).   -*- C -*- */

@@ -1,4 +1,4 @@
-## Copyright (C) 2005-2006, 2008-2015, 2018-2020 Free Software
+## Copyright (C) 2005-2006, 2008-2015, 2018-2021 Free Software
 ## Foundation, Inc.
 ##
 ## This program is free software: you can redistribute it and/or modify
@@ -12,7 +12,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 ## -------------------- ##
 ## Building & testing.  ##
@@ -1,6 +1,6 @@
 #! /bin/sh

-# Copyright (C) 2005-2015, 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2005-2015, 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 cat >input <<EOF
 1 2 3 * +
@@ -15,7 +15,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 2018-2021 Free Software Foundation, Inc.

 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -1,6 +1,6 @@
 #! /bin/sh

-# Copyright (C) 2018-2020 Free Software Foundation, Inc.
+# Copyright (C) 2018-2021 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
@@ -13,7 +13,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 cat >input <<EOF
 1 + 2 * 3
@@ -1,6 +1,6 @@
 /* Parser and scanner for calc in D.   -*- D -*-

-   Copyright (C) 2018-2020 Free Software Foundation, Inc.
+   Copyright (C) 2018-2021 Free Software Foundation, Inc.

   This file is part of Bison, the GNU Compiler Compiler.

@@ -15,7 +15,7 @@
   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 <http://www.gnu.org/licenses/>.  */
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

 %language "D"

@@ -1,4 +1,4 @@
-## Copyright (C) 2018-2020 Free Software Foundation, Inc.
+## Copyright (C) 2018-2021 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
@@ -11,7 +11,7 @@
 ## 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 <http://www.gnu.org/licenses/>.
+## along with this program.  If not, see <https://www.gnu.org/licenses/>.

 ddir = $(docdir)/%D%

@@ -27,7 +27,7 @@ EXTRA_DIST += %D%/calc.test

 %D%/calc.d: %D%/calc.y $(dependencies)
 	$(AM_V_GEN)$(MKDIR_P) %D%
-	$(AM_V_at)$(BISON) $(srcdir)/%D%/calc.y -o $@
+	$(AM_V_at)$(BISON) -o $@ $(srcdir)/%D%/calc.y

 %D%/calc: %D%/calc.d
 	$(AM_V_GEN) $(DC) $(DCFLAGS) -of$@ %D%/calc.d
@@ -3,7 +3,7 @@

 # This file is part of GNU Bison

-# Copyright (C) 1992, 2000-2001, 2005-2006, 2009-2015, 2018-2020 Free
+# Copyright (C) 1992, 2000-2001, 2005-2006, 2009-2015, 2018-2021 Free
 # Software Foundation, Inc.
 #
 # This program is free software: you can redistribute it and/or modify
@@ -17,7 +17,7 @@
 # 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 <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.

 # Usage: extexi [OPTION...] input-file.texi ... -- [FILES to extract]

@@ -19,7 +19,7 @@ fill-column: 76
 ispell-dictionary: "american"
 End:

-Copyright (C) 2018-2020 Free Software Foundation, Inc.
+Copyright (C) 2018-2021 Free Software Foundation, Inc.

 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
--- a/Show More
+++ b/Show More
@@ -1 +1 @@
 .7
 .7.6