version 3.7.6

* NEWS: Record release date.
doc: don't mention YY_LOCATION_PRINT
2026-08-11 19:55:15 +00:00 · 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 · 2021-01-30 07:32:03 +01:00
247 changed files with 1967 additions and 1159 deletions
@@ -1 +1 @@
-3.7.2
+3.7.5
@@ -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 +1,72 @@
 GNU Bison NEWS
 * 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
@@ -229,7 +296,7 @@ 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.
@@ -3348,7 +3415,7 @@ 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,
@@ -4104,7 +4171,7 @@ 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.
@@ -4520,7 +4587,7 @@ 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/>
+- Autoconf <https://www.gnu.org/software/autoconf/>
- Automake <http://www.gnu.org/software/automake/>
+- Automake <https://www.gnu.org/software/automake/>
- Flex <http://www.gnu.org/software/flex/>
+- Flex <https://www.gnu.org/software/flex/>
- Gettext <http://www.gnu.org/software/gettext/>
+- Gettext <https://www.gnu.org/software/gettext/>
- Gperf <http://www.gnu.org/software/gperf/>
+- Gperf <https://www.gnu.org/software/gperf/>
- Graphviz <http://www.graphviz.org>
+- Graphviz <https://www.graphviz.org>
- Gzip <http://www.gnu.org/software/gzip/>
+- Gzip <https://www.gnu.org/software/gzip/>
- Help2man <http://www.gnu.org/software/help2man/>
+- Help2man <https://www.gnu.org/software/help2man/>
- Perl <http://www.cpan.org/>
+- Perl <https://www.cpan.org/>
- Rsync <http://samba.anu.edu.au/rsync/>
+- Rsync <https://rsync.samba.org/>
- Tar <http://www.gnu.org/software/tar/>
+- Tar <https://www.gnu.org/software/tar/>
- Texinfo <http://www.gnu.org/software/texinfo/>
+- Texinfo <https://www.gnu.org/software/texinfo/>
-Valgrind <http://valgrind.org/> is also highly recommended, if it supports
+Valgrind <https://www.valgrind.org/> is also highly recommended, if it
-your architecture.
+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/>.
@@ -728,7 +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
@@ -741,7 +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
@@ -877,7 +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.
@@ -156,6 +156,7 @@ 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]$$                  \
@@ -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.
+      /// Constructors for typed symbols.
-]b4_type_foreach([b4_basic_symbol_constructor_define])], [[
+]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.  */
+[[/* Identify Bison output, and Bison version.  */
-#define YYBISON 1
+#define YYBISON ]b4_version[
-/* Bison version.  */
+/* Bison version string.  */
-#define YYBISON_VERSION "]b4_version["
+#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
+[m4_ifvaln([$1], [  YY_USE ([$1]);])dnl
-b4_locations_if([m4_ifvaln([$2], [  YYUSE ([$2]);])])dnl
+b4_locations_if([m4_ifvaln([$2], [  YY_USE ([$2]);])])dnl
-b4_parse_param_for([Decl], [Formal], [  YYUSE (Formal);
+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                     \
+# elif ((!defined __cplusplus || defined __clang__) \
-        && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0)  \
+        && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
-            || 4 < __GNUC__ + (7 <= __GNUC_MINOR__) \
+            || (!defined __STRICT_ANSI__ \
-            || (defined __apple_build_version__ \
+                && (__4 < __GNUC__ + (7 <= __GNUC_MINOR__) \
-                ? 6000000 <= __apple_build_version__ \
+                    || (defined __apple_build_version__ \
-                : 3 < __clang_major__ + (5 <= __clang_minor__))))
+                        ? 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.  */
+[[/* Token kinds.  */
-m4_join([
+#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.  */
+[[/** Version number for the Bison executable that generated this parser.  */
-  public static immutable string yy_bison_version = "b4_version";
+  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);
+  YY_USE (yy0);
-  YYUSE (yy1);
+  YY_USE (yy1);
  switch (yyn)
    {
@@ -1795,8 +1804,8 @@ static YYRESULTTAG
 yyreportAmbiguity (yySemanticOption* yyx0,
                   yySemanticOption* yyx1]b4_pure_formals[)
 {
-  YYUSE (yyx0);
+  YY_USE (yyx0);
-  YYUSE (yyx1);
+  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);]])[
+    YY_USE (yylocationp);]])[
-    YYUSE (yyvaluep);
+    YY_USE (yyvaluep);
    std::ostream& yyo = debug_stream ();
    std::ostream& yyoutput = yyo;
-    YYUSE (yyoutput);
+    YY_USE (yyoutput);
    ]b4_symbol_actions([printer])[
  }
@@ -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.  */
+[[  /** Version number for the Bison executable that generated this parser.  */
-  public static final String bisonVersion = "b4_version";
+  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_; }
+      const symbol_type& lookahead () const YY_NOEXCEPT { return yyla_; }
-      symbol_kind_type token () const { return yyla_.kind (); }]b4_locations_if([[
+      symbol_kind_type token () const YY_NOEXCEPT { return yyla_.kind (); }]b4_locations_if([[
-      const location_type& location () const { return yyla_.location; }
+      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>]])[
+[b4_parse_assert_if([[#include <typeinfo>
-#ifndef YY_ASSERT
+#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))])[
-    {
+    {]b4_parse_assert_if([[
-      YY_ASSERT (sizeof (T) <= size);
+      ]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([
+    {]b4_parse_assert_if([[
-      YY_ASSERT (!yytypeid_);
+      ]b4_assert[ (!yytypeid_);
-      YY_ASSERT (sizeof (T) <= size);
+      ]b4_assert[ (sizeof (T) <= size);
-      yytypeid_ = & typeid (T);])[
+      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([
+    {]b4_parse_assert_if([[
-      YY_ASSERT (!yytypeid_);
+      ]b4_assert[ (!yytypeid_);
-      YY_ASSERT (sizeof (T) <= size);
+      ]b4_assert[ (sizeof (T) <= size);
-      yytypeid_ = & typeid (T);])[
+      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([
+    {]b4_parse_assert_if([[
-      YY_ASSERT (!yytypeid_);
+      ]b4_assert[ (!yytypeid_);
-      YY_ASSERT (sizeof (T) <= size);
+      ]b4_assert[ (sizeof (T) <= size);
-      yytypeid_ = & typeid (T);])[
+      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([
+    {]b4_parse_assert_if([[
-      YY_ASSERT (yytypeid_);
+      ]b4_assert[ (yytypeid_);
-      YY_ASSERT (*yytypeid_ == typeid (T));
+      ]b4_assert[ (*yytypeid_ == typeid (T));
-      YY_ASSERT (sizeof (T) <= size);])[
+      ]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([
+    {]b4_parse_assert_if([[
-      YY_ASSERT (yytypeid_);
+      ]b4_assert[ (yytypeid_);
-      YY_ASSERT (*yytypeid_ == typeid (T));
+      ]b4_assert[ (*yytypeid_ == typeid (T));
-      YY_ASSERT (sizeof (T) <= size);])[
+      ]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([
+    {]b4_parse_assert_if([[
-      YY_ASSERT (yytypeid_);
+      ]b4_assert[ (yytypeid_);
-      YY_ASSERT (*yytypeid_ == *that.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_token_kind(SYMBOL-NUM)
-[b4_symbol_if([$1], [is_token],
+# -------------------------
-              [b4_symbol_if([$1], [has_id],
+# Some tokens don't have an ID.
-                            [tok == token::b4_symbol([$1], [id])],
+m4_define([b4_token_kind],
-                            [tok == b4_symbol([$1], [code])])])])
+[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])
@@ -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:
+# the MathJax output. See the MathJax site
-# http://docs.mathjax.org/en/latest/output.html) for more details.
+# <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
+# https://www.graphviz.org/), a graph visualization toolkit from AT&T
-# Bell Labs. The other options in this section have no effect if this option is
+# and Lucent Bell Labs. The other options in this section have no
-# set to 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
+@node Rpcalc Exp
-@subsubsection Explanation of @code{expr}
+@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
@@ -7808,7 +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.
  @{
@@ -9945,10 +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
+One difficulty is that conflicts occur in the @emph{automaton}, and it can
-tricky to related them to issues in the @emph{grammar} itself.  With
+be tricky to relate them to issues in the @emph{grammar} itself.  With
-experience and patience, analysis the detailed description of the automaton
+experience and patience, analysis of the detailed description of the
-(@pxref{Understanding}) allows to find example strings that reach these conflicts.
+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
@@ -10101,7 +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
@@ -11868,8 +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}
+Bison, in @uref{https://www.graphviz.org/, Graphviz}
-@uref{http://www.graphviz.org/doc/info/lang.html, DOT} format.
+@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.
@@ -11987,7 +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.
@@ -12002,7 +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
@@ -13083,7 +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.
@@ -13098,7 +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
@@ -13179,7 +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.
@@ -13194,7 +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
@@ -13246,7 +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.
@@ -13261,7 +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
@@ -13458,7 +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.
@@ -13473,7 +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
@@ -13554,6 +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
@@ -13705,7 +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.
@@ -13720,7 +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
@@ -14562,7 +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}.
@@ -14666,6 +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
@@ -15080,7 +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
@@ -15433,6 +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
@@ -15905,35 +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]
@@ -15957,14 +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
@@ -16052,8 +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                                                    \
@@ -56,7 +56,7 @@ MAINTAINERCLEANFILES = $(CROSS_OPTIONS_TEXI)
 # Fix Info's @code in @deftype
-# https://lists.gnu.org/archive/html/help-texinfo/2019-11/msg00004.html
+# 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	\
@@ -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
@@ -1072,7 +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.
@@ -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%
@@ -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%
@@ -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
@@ -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
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Akim Demaille	b458b34f94	version 3.7.6 * NEWS: Record release date.	2021-03-08 06:15:53 +01:00
Akim Demaille	09a22da8c8	doc: don't mention YY_LOCATION_PRINT * doc/bison.texi (Syntax Error Reporting Function): Don't refer to YY_LOCATION_PRINT, it is a private internal detail.	2021-03-07 18:41:38 +01:00
Akim Demaille	cf899f7a7c	yacc: fix push parser When a pstate is used for multiple successive parses, some state may leak from one run into the following one. That was introduced in `330552ea49` "yacc.c: push: don't clear the parser state when accepting/rejecting". Reported by Ryan <[email protected]> https://lists.gnu.org/r/bug-bison/2021-03/msg00000.html * data/skeletons/yacc.c (yypush_parse): We reusing a pstate from a previous run, do behave as if it were the first run. * tests/push.at (Pstate reuse): Check this.	2021-03-07 18:41:38 +01:00
Akim Demaille	a774839ca8	tables: fix again the handling of useless tokens The right-shift added in `c22902e360` ("tables: fix handling for useless tokens") is incorrect. In particular, we need to reset the "new" bits. Reported by Balázs Scheidler. https://github.com/akimd/bison/issues/74 * src/tables.c (pos_set_set): Fix the right-shift.	2021-03-07 11:56:30 +01:00
Paul EggertandAkim Demaille	ef3adfa0fb	Update URLs to prefer https: to http: Also, fix a few http: URLs that were no longer working.	2021-01-30 07:32:03 +01:00
Akim Demaille	4083ee52b5	doc: fix typo Reported by Kaz Kylheku. https://lists.gnu.org/r/bison-patches/2020-11/msg00019.html * doc/bison.texi (Versioning): here.	2021-01-24 08:55:42 +01:00
Kaz KylhekuandAkim Demaille	3c47ed0fe6	doc: document best deployment practices. * doc/bison.texi (Versioning): New node about practices regarding dealing with multiple versions of Bison.	2021-01-24 08:55:30 +01:00
Akim Demaille	1ff6bcb2f1	maint: post-release administrivia * NEWS: Add header line for next release. * .prev-version: Record previous version. * cfg.mk (old_NEWS_hash): Auto-update.	2021-01-24 08:53:16 +01:00
Akim Demaille	2fac23b9dd	version 3.7.5 * NEWS: Record release date.	2021-01-24 08:30:41 +01:00
Akim Demaille	c22902e360	tables: fix handling for useless tokens In some rare conditions, the generated parser can be wrong when there are useless tokens. Reported by Balázs Scheidler. https://github.com/akimd/bison/issues/72 Balázs managed to prove that the bug was introduced in commit `af1c6f973a` Author: Theophile Ranquet <[email protected]> Date: Tue Nov 13 10:38:49 2012 +0000 tables: use bitsets for a performance boost Suggested by Yuri at <http://lists.gnu.org/archive/html/bison-patches/2012-01/msg00000.html>. The improvement is marginal for most grammars, but notable for large grammars (e.g., PosgreSQL's postgre.y), and very large for the sample.y grammar submitted by Yuri in http://lists.gnu.org/archive/html/bison-patches/2012-01/msg00012.html. Measured with --trace=time -fsyntax-only. parser action tables postgre.y sample.y Before 0,129 (44%) 37,095 (99%) After 0,117 (42%) 5,046 (93%) * src/tables.c (pos): Replace this set of integer coded as an unsorted array of integers with... (pos_set): this bitset. which was implemented long ago, but that I installed only recently (March 2019), first published in v3.3.90. That patch introduces a bitset to represent a set of integers. It managed negative integers by using a (fixed) base (the smallest integer to represent). It avoided negative accesses into the bitset by ignoring integers smaller than the base, under the asumption that these cases correspond to useless tokens that are ignored anyway. While it turns out to be true for all the test cases in the test suite (!), Balázs' use case demonstrates that it is not always the case. So we need to be able to accept negative integers that are smaller than the current base. "Amusingly" enough, the aforementioned patch was visibly unsure about itself: /* Store PLACE into POS_SET. PLACE might not belong to the set of possible values for instance with useless tokens. It would be more satisfying to eliminate the need for this 'if'. / This commit needs several improvements in the future: - support from bitset for bit assignment and shifts - amortized resizing of pos_set - test cases src/tables.c (pos_set_base, pos_set_dump, pos_set_set, pos_set_test): New. Use them instead of using bitset_set and bitset_test directly.	2021-01-24 08:28:45 +01:00
Vincent ImbimboandAkim Demaille	2c294c1325	cex: fix state-item pruning There were several bugs in pruning that would leave the state-item graph in an inconsistent state which could cause crashes later on: - Pruning now happens in one pass instead of two. - Disabled state-items no longer prune the state-items they transition to if that state-item has other states that transition to it. - State-items that transition to disabled state-items are always pruned even if they have productions. Reported by Michal Bartkowiak <[email protected]> https://lists.gnu.org/r/bug-bison/2021-01/msg00000.html and Zartaj Majeed https://github.com/akimd/bison/issues/71 * src/state-item.c (prune_forward, prune_backward): Fuse into... (prune_state_item): this. Adjust callers.	2021-01-24 08:24:56 +01:00
Akim Demaille	236b85dd28	package: pacify syntax-check * cfg.mk: Currently we cannot update gnulib because of portability issues with ancient versions of clang (https://lists.gnu.org/r/bug-gnulib/2021-01/msg00241.html). So skip the check about copyright date for gnulib.	2021-01-23 15:08:48 +01:00
Akim Demaille	4109d56aa9	news: update	2021-01-23 15:02:49 +01:00
Akim Demaille	003ca0498d	package: bump copyrights to 2021 Run 'make update-copyright'.	2021-01-23 15:02:49 +01:00
Akim Demaille	3abad26a2d	%merge: associate it to its first definition, not the latest Currently each time we meet %merge we record this location as the defining location (and symbol). Instead, record the first definition. In the generated code we go from yy0->A = merge (yy0, yy1); to yy0->S = merge (yy0, yy1); where S was indeed the first symbol, and in the diagnostics we go from glr-regr18.y:30.18-24: error: result type clash on merge function 'merge': <type2> != <type1> 30 \| sym2: sym3 %merge<merge> { $$ = $1; } ; \| ^~~~~~~ glr-regr18.y:29.18-24: note: previous declaration 29 \| sym1: sym2 %merge<merge> { $$ = $1; } ; \| ^~~~~~~ glr-regr18.y:31.13-19: error: result type clash on merge function 'merge': <type3> != <type2> 31 \| sym3: %merge<merge> { $$ = 0; } ; \| ^~~~~~~ glr-regr18.y:30.18-24: note: previous declaration 30 \| sym2: sym3 %merge<merge> { $$ = $1; } ; \| ^~~~~~~ to glr-regr18.y:30.18-24: error: result type clash on merge function 'merge': <type2> != <type1> 30 \| sym2: sym3 %merge<merge> { $$ = $1; } ; \| ^~~~~~~ glr-regr18.y:29.18-24: note: previous declaration 29 \| sym1: sym2 %merge<merge> { $$ = $1; } ; \| ^~~~~~~ glr-regr18.y:31.13-19: error: result type clash on merge function 'merge': <type3> != <type1> 31 \| sym3: %merge<merge> { $$ = 0; } ; \| ^~~~~~~ glr-regr18.y:29.18-24: note: previous declaration 29 \| sym1: sym2 %merge<merge> { $$ = $1; } ; \| ^~~~~~~ where both duplicates are reported against definition 1, rather than using definition 1 as a reference when diagnosing about definition 2, and then 2 as a reference for 3. * src/reader.c (record_merge_function_type): Keep the first definition. * tests/glr-regression.at: Adjust.	2021-01-23 15:02:49 +01:00
Akim Demaille	1bac4ecc44	%merge: fix compatibility with api.value.type=union Reported by Jot Dot. https://lists.gnu.org/r/help-bison/2020-12/msg00014.html * data/skeletons/glr.c, data/skeletons/glr2.cc (b4_call_merger): Use the symbol's slot, not its type. * examples/c/glr/c++-types.y: Use explicit per-symbol typing together with api.value.type=union. (yylex): Use yytoken_kind_t.	2021-01-23 15:02:49 +01:00
Akim Demaille	84b00b6bf0	%merge: delegate the generation of calls to mergers to m4 Don't generate C code from bison, leave that to the skeletons. * src/output.c (merger_output): Emit invocations to b4_call_merger. * data/skeletons/glr.c (b4_call_merger): New.	2021-01-23 15:02:49 +01:00
Akim Demaille	a26f7cf98f	%merge: let mergers record a typing-symbol, rather than a type Symbols are richer than types, and in M4 it is my simpler (and more common) to deal with symbols rather than types. So let's associate mergers to a symbol rather than a type name. * src/reader.h (merger_list): Replace the 'type' member by a symbol member. * src/reader.c (record_merge_function_type): Take a symbol as argument, rather than a type name. * src/output.c (merger_output): Adjust.	2021-01-23 10:43:25 +01:00
Akim Demaille	0317055bb0	%merge: clearer tests on diagnostics * tests/glr-regression.at: Use caret errors.	2021-01-23 10:43:25 +01:00
Akim Demaille	c73dcd6958	skeletons: introduce "slot"s for symbols Extracted from `d9cf99b6a5`, in the master branch. * data/skeletons/bison.m4 (b4_symbol_slot): New, with safer semantics than type and type_tag.	2021-01-23 10:43:25 +01:00
Akim Demaille	11f6839645	style: YYUSE is private, make it YY_USE This macro is not exposed to users, make start it with 'YY_'. * data/skeletons/bison.m4, data/skeletons/c.m4, data/skeletons/glr.c, * data/skeletons/glr.cc, data/skeletons/lalr1.cc, * src/parse-gram.c, tests/actions.at, tests/c++.at, tests/headers.at, * tests/local.at (YYUSE): Rename as... (YY_USE): this.	2021-01-23 10:43:25 +01:00
Akim Demaille	4910c02579	package: codespell * src/parse-gram.y: Fix spelling.	2021-01-23 10:43:25 +01:00
Akim Demaille	83bc889536	cex: fix traces: fix display of disabled items The display of disabled state items is incorrect. The item is stuttered, and lacks on end-of-line. From State 7: 1 exp: exp • "⊕" exp -> 1 exp: exp "⊕" • exp <- 1 exp: • exp "⊕" exp 2 exp: exp • "+" exp 2 exp: exp • "+" exp DISABLED 2 exp: exp "+" exp • <- 2 exp: exp "+" • exp 3 exp: exp • "+" exp 3 exp: exp • "+" exp DISABLED 3 exp: exp "+" exp • <- 3 exp: exp "+" • exp to State 7: 1 exp: exp • "⊕" exp -> 1 exp: exp "⊕" • exp <- 1 exp: • exp "⊕" exp 2 exp: exp • "+" exp DISABLED 2 exp: exp "+" exp • <- 2 exp: exp "+" • exp 3 exp: exp • "+" exp DISABLED 3 exp: exp "+" exp • <- 3 exp: exp "+" • exp * src/state-item.c (state_items_report): Don't issue disabled items twice, and issue two '\n' at their end. * tests/conflicts.at: Check it.	2021-01-23 10:43:04 +01:00
Akim Demaille	2f554e6260	cex: fix traces: add missing end-of-lines In `430ca0fc63`, I completely forgot that `puts` adds a `\n`. * src/lssi.c, src/state-item.c: Restore missing end-of-lines in the output.	2021-01-23 10:42:52 +01:00
Akim Demaille	7a31b6bb7f	cex: add support for $TIME_LIMIT * src/counterexample.c (TIME_LIMIT): Replace with... (time_limit): this. (counterexample_init): Check $TIME_LIMIT. * src/scan-gram.l: Reorder includes.	2021-01-23 09:40:32 +01:00
Akim Demaille	8320691a63	cex: send traces to stderr, not stdout When comparing traces from different machines, the mixture of stdout/stderr in the output are making things uselessly difficult. * src/lssi.c, src/state-item.c: Output debug traces on stderr.	2021-01-23 09:39:27 +01:00
Akim Demaille	3b03c62e49	c++: I'm tired of Flex's warnings * doc/bison.texi: Disable another warning I'm tired to see. New releases would be most welcome.	2021-01-23 09:39:15 +01:00
Akim Demaille	a700a13822	glr.cc: don't "leak" yyparse When using glr.cc, the C function yyparse is an internal detail that should not be exposed. Users might call it by accident (I did). * data/skeletons/glr.c (yyparse): When used for glr.cc, rename as yy_parse_impl. * data/skeletons/glr.cc: Adjust.	2021-01-23 09:37:05 +01:00
Akim Demaille	1d3df34671	tables: avoid warnings and save bits The yydefgoto table uses -1 as an invalid for an impossible case (we never use yydefgoto[0], since it corresponds to the reduction to $accept, which never happens). Since yydefgoto is a table of state numbers, this -1 forces a signed type uselessly, which (1) might trigger compiler warnings when storing a value from yydefgoto into a state number (nonnegative), and (2) wastes bits which might result in using a int16 where a uint8 suffices. Reported by Jot Dot <[email protected]>. https://lists.gnu.org/r/bug-bison/2020-11/msg00027.html * src/tables.c (default_goto): Use 0 rather than -1 as invalid value. * tests/regression.at: Adjust.	2021-01-23 09:36:24 +01:00
Akim Demaille	89d2b69c1b	c++: use noexcept where appropriate Reported by Don Macpherson. https://github.com/akimd/bison/issues/63 https://github.com/akimd/bison/issues/64 * data/skeletons/c++.m4, data/skeletons/lalr1.cc: here.	2021-01-23 09:28:01 +01:00
Martin RehakandAkim Demaille	1e0b087244	examples: avoid "unbound variable" errors When the shell option `nounset` is set, we may get "unbound variable" errors. https://lists.gnu.org/r/bug-bison/2020-11/msg00013.html * examples/test (diff_opts): Be sure to initialize it.	2021-01-23 09:27:30 +01:00
Akim Demaille	4744faf205	autoconf: update	2021-01-23 09:24:11 +01:00
Akim Demaille	1ac973aa56	c: adjust _Noreturn to pedantic clang Reported by Joe Nelson <[email protected]>. https://lists.gnu.org/r/help-bison/2021-01/msg00004.html Fixed by Paul Eggert in gnulib. https://lists.gnu.org/r/bug-gnulib/2021-01/msg00156.html * data/skeletons/c.m4 (b4_attribute_define): Adjust _Noreturn to pedantic clang.	2021-01-23 09:24:01 +01:00
Paul Eggert	8358090292	c: port to HP-UX 11.23 Problem reported by Albert Chin in: https://lists.gnu.org/r/bug-bison/2021-01/msg00029.html * data/skeletons/c.m4 (b4_c99_int_type_define): Work around HP-UX bug.	2021-01-21 11:45:34 -08:00
Akim Demaille	0364dbacbf	maint: post-release administrivia * NEWS: Add header line for next release. * .prev-version: Record previous version. * cfg.mk (old_NEWS_hash): Auto-update.	2020-11-14 12:26:42 +01:00
Akim Demaille	7a11a9308c	version 3.7.4 * NEWS: Record release date.	2020-11-14 12:04:26 +01:00
Akim Demaille	d8cc6b073e	c++: shorten the assertions that check whether tokens are correct Before: YY_ASSERT (tok == token::YYEOF \|\| tok == token::YYerror \|\| tok == token::YYUNDEF \|\| tok == 120 \|\| tok == 49 \|\| tok == 50 \|\| tok == 51 \|\| tok == 52 \|\| tok == 53 \|\| tok == 54 \|\| tok == 55 \|\| tok == 56 \|\| tok == 57 \|\| tok == 97 \|\| tok == 98); After: YY_ASSERT (tok == token::YYEOF \|\| (token::YYerror <= tok && tok <= token::YYUNDEF) \|\| tok == 120 \|\| (49 <= tok && tok <= 57) \|\| (97 <= tok && tok <= 98)); Clauses are now also wrapped on several lines. This is nicer to read and diff, but also avoids pushing Visual C++ to its arbitrary limits (640K and lines of 16380 bytes ought to be enough for anybody, otherwise make an C2026 error). The useless parens are there for the dummy warnings about precedence (in the future, will we also have to put parens in `1+23`?). data/skeletons/variant.hh (_b4_filter_tokens, b4_tok_in, b4_tok_in): New. (_b4_token_constructor_define): Use them.	2020-11-13 06:17:52 +01:00
Akim Demaille	0264b4bca0	c++: don't glue functions together * data/skeletons/bison.m4 (b4_type_foreach): Accept a separator. * data/skeletons/c++.m4: Use it. And fix an incorrect comment.	2020-11-13 06:17:52 +01:00
Akim Demaille	8b424b865e	lalr1.cc: YY_ASSERT should use api.prefix Working on the previous commit I realized that YY_ASSERT was used in the generated headers, so must follow api.prefix to avoid clashes when multiple C++ parser with variants are used. Actually many more macros should obey api.prefix (YY_CPLUSPLUS, YY_COPY, etc.). There was no complaint so far, so it's not urgent enough for 3.7.4, but it should be addressed in 3.8. * data/skeletons/variant.hh (b4_assert): New. Use it. * tests/local.at (AT_YYLEX_RETURN): Fix. * tests/headers.at: Make sure variant-based C++ parsers are checked too. This test did find that YY_ASSERT escaped renaming (before the fix in this commit).	2020-11-13 06:17:52 +01:00
Akim Demaille	f4431ea115	c++: don't use YY_ASSERT at all if parse.assert is disabled In some extreme situations (about 800 tokens), we generate a single-line assertion long enough for Visual C++ to discard the end of the line, thus falling into parse ends for the missing `);`. On a shorter example: YY_ASSERT (tok == token::TOK_YYEOF \|\| tok == token::TOK_YYerror \|\| tok == token::TOK_YYUNDEF \|\| tok == token::TOK_ASSIGN \|\| tok == token::TOK_MINUS \|\| tok == token::TOK_PLUS \|\| tok == token::TOK_STAR \|\| tok == token::TOK_SLASH \|\| tok == token::TOK_LPAREN \|\| tok == token::TOK_RPAREN); Whether NDEBUG is used or not is irrelevant, the parser dies anyway. Reported by Jot Dot <[email protected]>. https://lists.gnu.org/r/bug-bison/2020-11/msg00002.html We should avoid emitting lines so long. We probably should also use a range-based assertion (with extraneous parens to pacify fascist compilers): YY_ASSERT ((token::TOK_YYEOF <= tok && tok <= token::TOK_YYUNDEF) \|\| (token::TOK_ASSIGN <= tok && ...) But anyway, we should simply not emit this assertion at all when not asked for. * data/skeletons/variant.hh: Do not define, nor use, YY_ASSERT when it is not enabled.	2020-11-13 06:17:52 +01:00
Akim Demaille	fe8c36ddca	c++: style: follow the Bison m4 quoting pattern * data/skeletons/variant.hh: here.	2020-11-13 06:17:24 +01:00
Akim Demaille	21c147b6e5	yacc.c: provide the Bison version as an integral macro Suggested by Balazs Scheidler. https://github.com/akimd/bison/issues/55 * src/muscle-tab.c (muscle_init): Move/rename `b4_version` to/as... * src/output.c (prepare): `b4_version_string`. Also define `b4_version`. * data/skeletons/bison.m4, data/skeletons/c.m4, data/skeletons/d.m4, * data/skeletons/java.m4: Adjust. * doc/bison.texi: Document it.	2020-11-11 09:08:57 +01:00
Akim Demaille	d3c575a6c6	regen	2020-11-11 08:47:23 +01:00
Akim Demaille	d8b49e2b73	style: make conversion of version string to int public * src/parse-gram.y (str_to_version): Rename as/move to... * src/strversion.h, src/strversion.c (strversion_to_int): these new files.	2020-11-11 08:47:23 +01:00
Akim Demaille	14c65a35f0	%require: accept version numbers with three parts ("3.7.4") * src/parse-gram.y (str_to_version): Support three parts. * data/skeletons/location.cc, data/skeletons/stack.hh: Adjust.	2020-11-11 08:47:23 +01:00
Todd C. MillerandAkim Demaille	c47bb87f9f	yacc.c: fix #definition of YYEMPTY When generating a C parser, YYEMPTY is present in enum yytokentype but there is no corresponding #define like there is for the other values. There is a special case for YYEMPTY in b4_token_enums but no corresponding case in b4_token_defines. * data/skeletons/c.m4 (b4_token_defines): Do define YYEMPTY.	2020-11-11 08:47:21 +01:00
Akim Demaille	98c35e0025	gnulib: update	2020-11-10 07:56:13 +01:00
Akim Demaille	bd6b046ce7	doc: fix incorrect section title Reported by Gaurav Singh <[email protected]>. https://lists.gnu.org/r/bug-bison/2020-11/msg00000.html * doc/bison.texi (Rpcalc Expr): Rename as... (Rpcalc Exp): this, as the nterm is named 'exp'.	2020-11-01 09:12:27 +01:00
Nick GassonandAkim Demaille	7c6e7bd300	doc: minor grammar fixes in counterexamples section * doc/bison.texi: Minor fixes in counterexamples section.	2020-10-28 06:36:43 +01:00
Akim Demaille	3cba59dd7f	doc: fix typo * README: here.	2020-10-14 21:12:04 +02:00
Akim Demaille	a15879c623	maint: post-release administrivia * NEWS: Add header line for next release. * .prev-version: Record previous version. * cfg.mk (old_NEWS_hash): Auto-update.	2020-10-13 07:23:28 +02:00