+** Updating
+
+The use of submodules make things somewhat different because git does
+not support recursive operations: submodules must be taken care of
+explicitly by the user.
+
+*** Updating Bison
+
+If you pull a newer version of a branch, say via "git pull", you might
+import requests for updated submodules. A simple "git diff" will
+reveal if the current version of the submodule (i.e., the actual
+contents of the gnulib directory) and the current request from the
+subscriber (i.e., the reference of the version of gnulib that the
+Bison repository requests) differ. To upgrade the submodules (i.e.,
+to check out the version that is actually requested by the subscriber,
+run "git submodule update".
+
+ $ git pull
+ $ git submodule update
+
+*** Updating a submodule
+To update a submodule, say gnulib, do as follows:
+
+Get the most recent version of the master branch from git.
+
+ $ cd gnulib
+ $ git fetch
+ $ git checkout -b master --track origin/master
+
+Make sure Bison can live with that version of gnulib.
+
+ $ cd ..
+ $ ./bootstrap
+ $ make distcheck
+
+Register your changes.
+
+ $ git checkin ...
+
+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/
+
+The Autoconf files we use are currently:
+
+ m4/m4.m4
+ lib/m4sugar/m4sugar.m4
+ lib/m4sugar/foreach.m4
+
+These files don't change very often in Autoconf, so it should be
+relatively straight-forward to examine the differences in order to
+decide whether to update.
+
+* Test suite
+
+** make check
+Use liberally.
+
+** Typical errors
+If the test suite shows failures such as the following one
+
+ .../bison/lib/getopt.h:196:8: error: redefinition of 'struct option'
+ /usr/include/getopt.h:54:8: error: previous definition of 'struct option'
+
+it probably means that some file was compiled without
+AT_DATA_SOURCE_PROLOGUE. This error is due to the fact that our -I options
+pick up gnulib's replacement headers, such as getopt.h, and this will go
+wrong if config.h was not included first.
+
+See tests/local.at for details.
+
+** make maintainer-check-valgrind
+This target uses valgrind both to check bison, and the generated parsers.
+
+This is not mature on Mac OS X. First, Valgrind does support the way bison
+calls m4, so Valgrind cannot be used to check bison on Mac OS X.
+
+Second, there are many errors that come from the platform itself, not from
+bison. build-aux/darwin11.4.0.valgrind addresses some of them.
+
+Third, valgrind issues warnings such as:
+
+ --99312:0:syswrap- WARNING: Ignoring sigreturn( ..., UC_RESET_ALT_STACK );
+
+which cause the test to fail uselessly. It is hard to ignore these errors
+with a major overhaul of the way instrumentation is performed in the test
+suite. So currently, do not try to run valgrind on Mac OS X.
+
+** Release checks
+Try to run the test suite with more severe conditions before a
+release:
+
+- Configure the package with --enable-gcc-warnings, so that one checks
+ that 1. Bison compiles cleanly, 2. the parsers it produces compile
+ cleanly too.
+
+- 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>).
+
+- Check with "make syntax-check" if there are issues diagnosed by
+ gnulib.
+
+- run "make maintainer-check" which:
+ - runs "valgrind -q bison" to run Bison under Valgrind.
+ - runs the parsers under Valgrind.
+ - runs the test suite with G++ as C compiler...
+
+- run "make maintainer-push-check", which runs "make maintainer-check"
+ while activating the push implementation and its pull interface wrappers
+ in many test cases that were originally written to exercise only the
+ pull implementation. This makes certain the push implementation can
+ perform every task the pull implementation can.
+
+- run "make maintainer-xml-check", which runs "make maintainer-check"
+ while checking Bison's XML automaton report for every working grammar
+ passed to Bison in the test suite. The check just diffs the output of
+ Bison's included XSLT style sheets with the output of --report=all and
+ --graph.
+
+- running "make maintainer-release-check" takes care of running
+ maintainer-check, maintainer-push-check and maintainer-xml-check.
+
+- Change tests/atlocal/CFLAGS to add your preferred options. For
+ instance, "-traditional" to check that the parsers are K&R. Note
+ that it does not make sense for glr.c, which should be ANSI, but
+ currently is actually GNU C, nor for lalr1.cc.
+
+- Test with a very recent version of GCC for both C and C++. Testing
+ with older versions that are still in use is nice too.
+
+
+* Release Procedure
+This section needs to be updated to take into account features from
+gnulib. In particular, be sure to read README-release.
+
+** Update the submodules. See above.
+
+** Update maintainer tools, such as Autoconf. See above.
+
+** Try to get the *.pot files to the Translation Project at least one
+week before a stable release, to give them time to translate them.
+Before generating the *.pot files, make sure that po/POTFILES.in and
+runtime-po/POTFILES.in list all files with translatable strings.
+This helps: grep -l '\<_(' *
+
+** Tests
+See above.
+
+** Update the foreign files
+Running "./bootstrap" in the top level should update them all for you.
+This covers PO files too. Sometimes a PO file contains problems that
+causes it to be rejected by recent Gettext releases; please report
+these to the Translation Project.
+
+** Update README
+Make sure the information in README is current. Most notably, make sure
+it recommends a version of GNU M4 that is compatible with the latest
+Bison sources.
+
+** Check copyright years.
+We update years in copyright statements throughout Bison once at the
+start of every year by running "make update-copyright". However, before
+a release, it's good to verify that it's actually been run. Besides the
+copyright statement for each Bison file, check the copyright statements
+that the skeletons insert into generated parsers, and check all
+occurrences of PACKAGE_COPYRIGHT_YEAR in configure.ac.
+
+** Update NEWS, commit and tag.
+See do-release-commit-and-tag in README-release. For a while, we used
+beta names such as "2.6_rc1". Now that we use gnulib in the release
+procedure, we must use "2.5.90", which has the additional benefit of
+being properly sorted in "git tag -l".
+
+** make alpha, beta, or stable
+See README-release.
+
+** Upload
+There are two ways to upload the tarballs to the GNU servers: using
+gnupload (from gnulib), or by hand. Obviously prefer the former. But
+in either case, be sure to read the following paragraph.
+
+*** Setup
+You need "gnupg".
+
+Make sure your public key has been uploaded at least to
+keys.gnupg.net. You can upload it with:
+
+ gpg --keyserver keys.gnupg.net --send-keys F125BDF3
+
+where F125BDF3 should be replaced with your key ID.
+
+*** Using gnupload
+You need "ncftp".
+
+At the end "make stable" (or alpha/beta) will display the procedure to
+run. Just copy and paste it in your shell.
+
+*** By hand
+
+The generic GNU upload procedure is at:
+
+ http://www.gnu.org/prep/maintain/maintain.html#Automated-FTP-Uploads
+
+Follow the instructions there to register your information so you're permitted
+to upload.
+
+Here's a brief reminder of how to roll the tarballs and upload them:
+
+*** make distcheck
+*** gpg -b bison-2.3b.tar.gz
+*** In a file named "bison-2.3b.tar.gz.directive", type:
+
+ version: 1.1
+ directory: bison
+ filename: bison-2.3b.tar.gz
+
+*** gpg --clearsign bison-2.3b.tar.gz.directive
+*** ftp ftp-upload.gnu.org # Log in as anonymous.
+*** cd /incoming/alpha # cd /incoming/ftp for full release.
+*** put bison-2.3b.tar.gz # This can take a while.
+*** put bison-2.3b.tar.gz.sig
+*** put bison-2.3b.tar.gz.directive.asc
+*** Repeat all these steps for bison-2.3b.tar.xz.
+
+** Update Bison manual on www.gnu.org.
+
+*** You need a non-anonymous checkout of the web pages directory.
+
+ $ cvs -d YOUR_USERID@cvs.savannah.gnu.org:/web/bison checkout bison
+
+*** Get familiar with the instructions for web page maintainers.
+http://www.gnu.org/server/standards/readme_index.html
+http://www.gnu.org/server/standards/README.software.html
+especially the note about symlinks.
+
+*** Build the web pages.
+Assuming BISON_CHECKOUT refers to a checkout of the Bison dir, and
+BISON_WWW_CHECKOUT refers to the web directory created above, do:
+
+ $ cd $BISON_CHECKOUT/doc
+ $ make stamp-vti
+ $ ../build-aux/gendocs.sh -o "$BISON_WWW_CHECKOUT/manual" \
+ bison "Bison - GNU parser generator"
+ $ cd $BISON_WWW_CHECKOUT
+
+Verify that the result looks sane.
+
+*** Commit the modified and the new files.
+
+*** Remove old files.
+Find the files which have not been overwritten (because they belonged to
+sections that have been removed or renamed):
+
+ $ cd manual/html_node
+ $ ls -lt
+
+Remove these files and commit their removal to CVS. For each of these
+files, add a line to the file .symlinks. This will ensure that
+hyperlinks to the removed files will redirect to the entire manual; this
+is better than a 404 error.
+
+There is a problem with 'index.html' being written twice (once for POSIX
+function 'index', once for the table of contents); you can ignore this
+issue.
+
+** Announce
+The "make stable" (or alpha/beta) command just created a template,
+$HOME/announce-bison-X.Y. Otherwise, to generate it, run:
+
+ make RELEASE_TYPE=alpha gpg_key_ID=F125BDF3 announcement
+
+where alpha can be replaced by beta or stable and F125BDF3 should be
+replaced with your key ID.
+
+Complete/fix the announcement file. The generated list of recipients
+(info-gnu@gnu.org, bug-bison@gnu.org, help-bison@gnu.org,
+bison-patches@gnu.org, and coordinator@translationproject.org) is
+appropriate for a stable release or a "serious beta". For any other
+release, drop at least info-gnu@gnu.org. For an example of how to
+fill out the rest of the template, search the mailing list archives
+for the most recent release announcement.
+
+For a stable release, send the same announcement on the comp.compilers
+newsgroup by sending email to compilers@iecc.com. Do not make any Cc as
+the moderator will throw away anything cross-posted or Cc'ed. It really
+needs to be a separate message.
+
+** Prepare NEWS
+So that developers don't accidentally add new items to the old NEWS
+entry, create a new empty entry in line 3 (without the two leading
+spaces):
+
+ * Noteworthy changes in release ?.? (????-??-??) [?]
+
+Push these changes.
+