Revert the --with-install-srcdir patch

Also, update description of debuginfo and sources to match
Debian and Red Hat more accurately, and move this sad tale
from INSTALL to etc/PROBLEMS which is a better home for it.
* Makefile.in (emacs_srcdir, install-c-src):
* configure.ac (emacs_srcdir, --with-install-srcdir):
* src/epaths.in (PATH_EMACS_SOURCE):
* src/lread.c (emacs-source-directory):
Remove.  All uses removed.
* lisp/emacs-lisp/find-func.el (find-function-C-source):
Do not worry about compressed C sources.
* src/lread.c: Do not include <dosname.h>.

Fix Bug#39253

* lisp/net/tramp.el (tramp-handle-shell-command): Set `default-directory'.

Fix problems in Tramp's async-shell-command

* lisp/net/tramp-adb.el (tramp-adb-handle-make-process):
* lisp/net/tramp-cache.el (top):
* lisp/net/tramp-sh.el (tramp-sh-handle-make-process):
Use `insert-file-contents-literally'.

* lisp/net/tramp.el (tramp-parse-file):
Use `insert-file-contents-literally'.
(tramp-handle-shell-command): Reorganize error-buffer handling.
(tramp-handle-start-file-process): Use `consp' instead of `listp'.

* test/lisp/net/tramp-tests.el (tramp-test31-interrupt-process):
Bind `delete-exited-processes'.
(tramp--test-async-shell-command): Bind `delete-exited-processes'.
Add additional `accept-process-output'.  Move cleanup of output
buffer ...
(tramp-test32-shell-command): ... here.  Test error buffer also
for `async-shell-command'.

* lisp/emacs-lisp/debug.el (debug): Merge the non-interactive cases

bug#38927

* src/mini-gmp.c: Fix comment typos.

Update mini-gmp

* src/mini-gmp.c, src/mini-gmp.h: Copy from GMP 6.2.0.
This incorporates:
2019-12-05 remove some sizeof(mp_limb_t)
2019-12-04 (mpn_invert_3by2): Remove special code for limb sizes
2019-12-04 (mpn_invert_3by2): Limit size of an intermediate
2019-11-20 (mpn_invert_3by2): Use xor instead of negation
2019-11-19 (mpn_invert_3by2): Move an assert earlier
2019-11-19 (mpn_invert_3by2): Add a new shortcut
2019-11-17 Prepend "unsigned" to MINI_GMP_LIMB_TYPE
2019-11-17 Enable testing with different limb sizes (types)
2019-11-20 Use already defined constants
2019-11-09 Avoid undefined behaviour with small limb sizes

Improve doc for emacs-source-directory (Bug#36527).

Propagate NSLocale into Emacs better

* src/emacs.c (main): Call ns_init_locale before using the
environment variable that ns_init_locale sets up (Bug#39248).

Add more tests for bookmark-bmenu-list

* test/lisp/bookmark-tests.el (cl-lib): Require.
(bookmark-test-bmenu-toggle-filenames)
(bookmark-test-bmenu-toggle-filenames/show)
(bookmark-test-bmenu-show-filenames)
(bookmark-test-bmenu-hide-filenames)
(bookmark-test-bmenu-bookmark, bookmark-test-bmenu-mark)
(bookmark-test-bmenu-any-marks, bookmark-test-bmenu-unmark)
(bookmark-test-bmenu-delete, bookmark-test-bmenu-locate): New
tests.

(bookmark-test-bmenu-edit-annotation/show-annotation): Rename from
'bookmark-bmenu-edit-annotation/show-annotation'.
(bookmark-test-bmenu-send-edited-annotation): Rename from
'bookmark-bmenu-send-edited-annotation'.
(bookmark-test-bmenu-send-edited-annotation/restore-focus): Rename
from 'bookmark-bmenu-send-edited-annotation/restore-focus'.

Fix Bug#39279

* lisp/net/tramp.el (tramp-completion-file-name-handler):
Fix thinko.  (Bug#39279)

Fix MS-Windows build broken by "Install C source code"

* nt/epaths.nt (PATH_EMACS_SOURCE): Add definition.

Install C source code for C-h f etc.

Without this change, on typical GNU/Linux distributions
like Debian, the first button of ‘C-h f car RET’ does not work
because the source code for ‘car’ is not installed (Bug#37527).
Fix this by installing the (compressed) C source code alongside
the (compressed) Lisp source code that is already installed.
This adds about 3 MB (about 2%) to the size of the installed files
on my platform.
* Makefile.in (emacs_srcdir): New macro.
(epaths-force): Substitute PATH_EMACS_SOURCE.
(install-c-src): New rule, that installs a copy of the C source
code if emacs_srcdir says to.
(install-arch-indep): Depend on it.
* configure.ac (emacs_srcdir): New var.
Add support for --disable-install-srcdir.
* lisp/emacs-lisp/find-func.el (find-function-C-source-directory):
Look in emacs-source-directory first.
(find-function-C-source): Also look for gzipped source files.
* lisp/startup.el (normal-top-level):
Also recode emacs-source-directory.
* src/epaths.in (PATH_EMACS_SOURCE): New macro.
* src/lread.c: Include dosname.h, for IS_ABSOLUTE_FILE_NAME.
(syms_of_lread): New var emacs-source-directory.

Remove (or double) redundant backslashes in string literals

See discussion at
https://lists.gnu.org/archive/html/emacs-devel/2020-01/msg00749.html .

* lisp/obsolete/iswitchb.el (iswitchb-summaries-to-end):
* test/src/regex-emacs-tests.el (regex-tests-BOOST-frob-escapes):
* test/lisp/help-fns-tests.el (help-fns-test-lisp-macro)
(help-fns-test-lisp-defun, help-fns-test-lisp-defsubst)
(help-fns-test-alias-to-defun, help-fns-test-bug23887):
Double backslashes for desired effect.
* lisp/org/ol.el (org-link-escape):
* lisp/net/nsm.el (nsm-protocol-check--rsa-kx)
(nsm-protocol-check--anon-kx, nsm-protocol-check--sha1-sig):
* lisp/obsolete/old-whitespace.el (whitespace-buffer):
* lisp/obsolete/rcompile.el (remote-compile-run-before):
* lisp/obsolete/vi.el (vi-end-of-blank-delimited-word):
* lisp/obsolete/vip.el (vip-current-major-mode)
(vip-paren-match, vip-switch-to-buffer)
(vip-switch-to-buffer-other-window, vip-kill-buffer)
(vip-get-ex-token, ex-edit):
* lisp/org/org-element.el (org-element--cache-sync-requests):
* lisp/org/org.el (org-sparse-tree):
* lisp/textmodes/reftex.el (reftex-report-bug):
* test/lisp/ibuffer-tests.el (ibuffer-save-filters):
* test/lisp/international/ucs-normalize-tests.el
(ucs-normalize-tests--insert-failing-lines):
* test/lisp/simple-tests.el (undo-test-kill-c-a-then-undo):
* test/lisp/textmodes/conf-mode-tests.el (conf-test-toml-mode):
* test/src/regex-emacs-tests.el (regex-tests-compare):
Remove redundant backslashes.

Fix iso8601-parse so unknown DST is -1, not nil

The convention in a decoded time’s dst flag is that t means DST,
nil means standard time, and -1 means unknown.  This differs from
the convention for other components of a decoded time, where nil
means unknown.  Fix some places where iso8601-parse mistakenly
treated nil as meaning that the dst flag was unknown.
* doc/lispref/os.texi (Time Parsing):
Adjust to match parse-time-string’s doc string.
* lisp/calendar/iso8601.el (iso8601-parse):
Set dst flag to nil if a numeric time zone or "Z" is given.
(iso8601--decoded-time): Default dst flag to -1 if no dst
flag or zone is given.
* lisp/calendar/time-date.el (decoded-time-set-defaults):
When we don’t have a time zone, set the dst flag consistently
with DEFAULT-ZONE.
* test/lisp/calendar/iso8601-tests.el (test-iso8601-date-years)
(test-iso8601-date-dates, test-iso8601-date-obsolete)
(test-iso8601-date-weeks, test-iso8601-date-ordinals)
(test-iso8601-time, test-iso8601-combined)
(test-iso8601-duration, test-iso8601-intervals)
(standard-test-dates, standard-test-time-of-day-local-time)
(standard-test-time-of-day-fractions)
(nonstandard-test-time-of-day-decimals)
(standard-test-time-of-day-beginning-of-day)
(standard-test-date-and-time-of-day, standard-test-interval):
Adjust tests to match fixed behavior.

Fix parse-time-string bug with ISO 8601 defaults

* lisp/calendar/parse-time.el (parse-time-string):
Do not use decoded-time-set-defaults; just let iso8601-parse
do its thing.

Add tests for version comparison predicates

* test/lisp/subr-tests.el (subr-test-version-list-<)
(subr-test-version-list-=, subr-test-version-list-<=): New tests.

Merge from origin/emacs-27

0bed550e21 (origin/emacs-27) Remove EmacsOpenPanel and EmacsSavePanel...
a0336029db * doc/emacs/files.texi (Auto Save Files): Improve indexing...
57fb8b10c1 Fix inaccurate wording in the Emacs manual
1c487747ab Update ERC module URLs
7d1e9c943f Minor doc string clarification in use-hard-newlines

; Merge from origin/emacs-27

The following commits were skipped:

e1deafd39d Backport: Fix bug 39218
d15f2d4cbc Prefer saying "Info manual" to "info page" in docs

Merge from origin/emacs-27

92f080dda8 Tab-bar related finishing touches.
224e8d1464 Make call_process call signal_after_change.  This fixes bu...
d02f2a793e * lisp/simple.el: Minor fixes to commentary.
196c42b8bf Fix a few typos
4f2b967795 Fix doc strings for image-dired rotation commands

# Conflicts:
# etc/NEWS

Make links in shr use separate mouse highlight regions

* lisp/net/shr.el (shr-urlify): Make adjacent links have separate
mouse hightlights (bug#39115).

Adapt tramp-test32-shell-command

* test/lisp/net/tramp-tests.el (tramp-test32-shell-command):
Test error buffer for synchronous `shell-command' only.

Minor code cleanup in Tramp

Support (un)mount of Tramp media devices

* lisp/net/tramp-gvfs.el (tramp-gvfs-gio-mapping): Add "gvfs-rename".
(tramp-gvfs-do-copy-or-rename-file): Use it.
(tramp-gvfs-activation-uri): Handle "media" method.
(tramp-gvfs-url-host): New defun.
(tramp-gvfs-handler-mounted-unmounted)
(tramp-gvfs-connection-mounted-p)
(tramp-gvfs-handler-volumeadded-volumeremoved)
(tramp-get-media-devices): Use it.

Expand Cairo and HarfBuzz descriptions

* etc/NEWS:
* configure.ac: Expand description of Cairo and Harfbuzz

Remove EmacsOpenPanel and EmacsSavePanel (bug#38031)

Warn about XFT and about Cairo without HarfBuzz

* configure.ac: Warn about libXFT usage.  Warn about using Cairo
without HarfBuzz.

* etc/NEWS: Announce XFT and HarfBuzz warnings.

* doc/emacs/files.texi (Auto Save Files): Improve indexing (bug#39259).

Fix inaccurate wording in the Emacs manual

* doc/emacs/custom.texi (Modifier Keys):
* doc/emacs/basic.texi (Inserting Text): Fix minor inaccuracies in
describing the 'Alt' modifier.  (Bug#39254)

Simplify locale setup

Stop exporting Vprevious_system_time_locale and
Vprevious_system_messages_locale to Elisp.  I did that export by
mistake in 1999, and the Elisp variables have never been used.
Simplifying this cruft should make it easier to fix Bug#39248.
* etc/NEWS: Mention this.
* src/emacs.c (main): Simplify locale initialization.
(synchronize_locale): Simplify.
(Vprevious_system_time_locale, Vprevious_system_messages_locale):
Now static variables not visible to Lisp, and defined only if
HAVE_SETLOCALE.
(Vprevious_system_messages_locale): Define only if LC_MESSAGES.

Update ERC module URLs

* lisp/erc/erc-autoaway.el, lisp/erc/erc-button.el,
lisp/erc/erc-compat.el, lisp/erc/erc-fill.el, lisp/erc/erc-imenu.el,
lisp/erc/erc-join.el, lisp/erc/erc-lang.el, lisp/erc/erc-match.el,
lisp/erc/erc-pcomplete.el, lisp/erc/erc-ring.el,
lisp/erc/erc-spelling.el, lisp/erc/erc-stamp.el,
lisp/erc/erc-track.el: Update URL to friendlier form, over https.
* lisp/erc/erc-ibuffer.el: Remove URL to nonexistent page.
* lisp/erc/erc-list.el, lisp/erc/erc-log.el, lisp/erc/erc-notify.el,
lisp/erc/erc-replace.el, lisp/erc/erc-services.el,
lisp/erc/erc-sound.el, lisp/erc/erc-speedbar.el,
lisp/erc/erc-truncate.el: Add URL to corresponding EmacsWiki page.

Make so-long test pass following lisp-mnt change

* lisp/so-long.el (so-long-commentary): Update for lisp-mnt change.

Globally sanitize single-file package long descriptions (Bug#37548)

Consistent with multi-file package descriptions which don’t have
commentary sections nor double semicolon prefixes.
* lisp/emacs-lisp/lisp-mnt.el (lm-commentary): Remove commentary
header, double semicolon prefixes of each line, trailing new-lines and
trailing white-space from commentary.
* lisp/emacs-lisp/package.el (package--get-description)
(describe-package-1):
* lisp/finder.el (finder-commentary):
* lisp/info.el (Info-finder-find-node): Remove ad-hoc sanitation.

Unbreak byte compilation

* lisp/emacs-lisp/bytecomp.el (byte-compile-fix-header):
Update for recent header changes.
(byte-compile-insert-header): Add more padding.

Remove irrelevant info from .elc headers

* lisp/emacs-lisp/bytecomp.el (byte-compile-insert-header): Don't
insert information on ancient Emacs in bytecode headers.  (Bug#39233)

Prefer saying "Info manual" to "info page" in docs

Pointed out by Eli Zaretskii in:
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=39215#14
* doc/emacs/Makefile.in:
* doc/lispintro/Makefile.in:
* doc/lispref/Makefile.in:
* doc/misc/Makefile.in:
* lisp/dired-x.el (top-level):
* lisp/gnus/gnus-sum.el (gnus-summary-mode):
* lisp/progmodes/cperl-mode.el (cperl-info-page): Doc fix; prefer
saying "Info manual" over "info page".

Implement "/media::" default host name in Tramp

* doc/misc/tramp.texi (GVFS-based methods): Describe default
/media:: file name.

* lisp/net/tramp-cache.el (tramp-get-file-property)
(tramp-set-file-property): Check, whether
`tramp-cache-{g,s}et-count-*' objects are numbers.

* lisp/net/tramp-gvfs.el (top): Don't set global default for
"media" in `tramp-default-host-alist'.
(tramp-gvfs-handler-volumeadded-volumeremoved): New defun.
(top): Register "org.gtk.Private.RemoteVolumeMonitor.VolumeAdded"
and "org.gtk.Private.RemoteVolumeMonitor.VolumeRemoved" signals.
(tramp-get-media-devices): Set defaults for "media" in
`tramp-default-host-alist'.

Minor doc string clarification in use-hard-newlines

* lisp/textmodes/paragraphs.el (use-hard-newlines): Clarify that
this minor mode isn't global (bug#20461).

Fix bug 39218

* lisp/simple.el (shell-command):
Ensure a shell command ending with `&' is run asynchronously.

Backport: Fix bug 39218

* lisp/simple.el (shell-command):
Ensure a shell command ending with `&' is run asynchronously.

Fix crash when sending Gnus message (Bug#39207)

* src/alloc.c (resize_string_data): The string must be multibyte.
When not bothering to reallocate, do bother to change the byte count.
* test/src/alloc-tests.el (aset-nbytes-change) New test.

Prefer saying "Info manual" to "info page" in docs

Pointed out by Eli Zaretskii in:
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=39215#14
* doc/emacs/Makefile.in:
* doc/lispintro/Makefile.in:
* doc/lispref/Makefile.in:
* doc/misc/Makefile.in:
* lisp/dired-x.el (top-level):
* lisp/gnus/gnus-sum.el (gnus-summary-mode):
* lisp/progmodes/cperl-mode.el (cperl-info-page): Doc fix; prefer
saying "Info manual" over "info page".

Tab-bar related finishing touches.

* lisp/tab-bar.el (tab-bar-tab-name-ellipsis): Use shorter name
instead of tab-bar-tab-name-truncated-ellipsis.
(tab-bar-new-tab-to) <defcustom>: Add 'function' option.
(tab-bar-new-tab-to) <function>: Use it.

* lisp/tab-line.el (tab-line-close-tab): Add missing arg 'tab' to
tab-line-close-tab-function funcall.

Make call_process call signal_after_change.  This fixes bug #38691.

Now, functions such as call-proess-region invoke after-change-functions
correctly.

* src/callproc.c (call_process): Call prepare_to_modify_buffer in a single
place, no longer delegating the task to insert_1_both, etc.  Call
signal_after_change in each of two code branches, such that
before-change-functions and after-change-functions are always called in
balanced pairs.

* lisp/simple.el: Minor fixes to commentary.

Fix a few typos

* etc/NEWS: Fix a typo.

* src/xdisp.c (try_window_reusing_current_matrix, try_window_id):
* src/dispnew.c (scrolling_window): Fix typos in comments.

Fix doc strings for image-dired rotation commands

* lisp/image-dired.el (image-dired-rotate-thumbnail-left)
(image-dired-rotate-thumbnail-right)
(image-dired-rotate-original-left)
(image-dired-rotate-original-right): Move the text in the doc
strings about rotating the originals to the correct commands
(bug#38928).

Merge from origin/emacs-27

3b0938c042 (origin/emacs-27) Render Ido suggestions using an overlay
d5d90dc412 * doc/misc/tramp.texi (Bug Reports): Encourage use of "ema...
ac09e8e121 * lisp/vc/smerge-mode.el (smerge-match-conflict): Fix bug#...
7e37e61f4b Correct statement about ftcr and recommend HarfBuzz
4aec94da37 Avoid leaving artifacts when the system caret is used on w32
5abd8d73b0 Improve display of temporary echo messages

; Merge from origin/emacs-27

The following commit was skipped:

f2f9f2f98e * lisp/menu-bar.el: Remove desktop-save-mode from release ...

Merge from origin/emacs-27

3ba0db41e3 Allow optional truncation of tab names in tab-bar and tab-...
7dd065fc7b Small fixes in documentation.
06166aa719 Improve explanation of available font backends under X
2eb834ead4 Clear output data pointer on NS

Add new Tramp method "media"

* doc/misc/tramp.texi (Quick Start Guide, GVFS-based methods):
Add media devices.

* etc/NEWS: Mention new Tramp method "media".

* lisp/net/tramp-gvfs.el (tramp-gvfs-methods): Add "media" method.
(tramp-goa-methods): Add tramp-autoload cookie.
(tramp-media-methods): New defvar.
(tramp-gvfs-service-volumemonitor): New defsubst.
(top): Remove media methods if not supported.  Add defaults for
`tramp-default-host-alist'.
(tramp-goa-account): Rename from `tramp-goa-name'.  Adapt all callees.
(tramp-gvfs-service-afc-volumemonitor)
(tramp-gvfs-service-goa-volumemonitor)
(tramp-gvfs-service-gphoto2-volumemonitor)
(tramp-gvfs-service-mtp-volumemonitor)
(tramp-gvfs-path-remotevolumemonitor)
(tramp-gvfs-interface-remotevolumemonitor): New defconsts.
(tramp-media-device): New defstruct.
(tramp-gvfs-activation-uri): New defun.
(tramp-gvfs-url-file-name): Use it.
(tramp-gvfs-handler-mounted-unmounted)
(tramp-gvfs-connection-mounted-p, tramp-gvfs-mount-spec):
Handle "media" method.
(tramp-get-goa-account): Rename from `tramp-make-goa-name'.  Adapt
all callees.
(tramp-get-goa-accounts): Adapt docstring.  Cache with nil key.
(tramp-parse-goa-accounts, tramp-get-media-device)
(tramp-get-media-devices)
(tramp-parse-media-names): New defuns.
(top): Rework completion function registration.

* lisp/net/tramp.el (tramp-dns-sd-service-regexp): New defconst.
(tramp-set-completion-function): Use it.

Add \sqrt[4] as Latex input method, too

* lisp/leim/quail/latin-ltx.el: Add \sqrt[4] as input method
(bug#25594).

Add \sqrt and \sqrt[3] as Latex input methods

* lisp/leim/quail/latin-ltx.el: Add \sqrt and \sqrt[3] as input
methods (bug#25594).

Support solar and lunar eclipses in Calendar

* lisp/calendar/lunar.el (eclipse-check): New function to display
solar and lunar eclipses (bug#20414).
(lunar-phase): Use it.
(calendar-lunar-phases): Ditto.

Default lisp-mode to use Common Lisp indentation

* lisp/emacs-lisp/lisp-mode.el (lisp-mode): Use
common-lisp-indent-function instead of lisp-indent-function as
Common Lisp is the most common non-Emacs Lisp today (bug#10097).

Make find-file-at-point respect port numbers in Tramp file name

* lisp/ffap.el (ffap-string-at-point-mode-alist): Respect port
numbers in files names like /ssh:root@127.0.0.1#2222:/root/ (bug#20412).

Render Ido suggestions using an overlay

* lisp/ido.el (ido--overlay): New variable.
(ido-exhibit): Render with 'after-string' on an overlay
(bug#38457).

Minor cleanup in {autorevert,filenotify,shadowfile}-tests.el

* test/lisp/autorevert-tests.el (tramp-message-show-message):
* test/lisp/shadowfile-tests.el (tramp-message-show-message):
* test/lisp/filenotify-tests.el (tramp-message-show-message)
Do Not set.
(file-notify-test04-autorevert): Inhibit messages.

* doc/misc/tramp.texi (Bug Reports): Encourage use of "emacs -Q".

* test/lisp/auth-source-pass-tests.el: Test for multiple ports.

* lisp/vc/smerge-mode.el (smerge-match-conflict): Fix bug#38456

This situation is not an internal error, but a perfectly normal occurrence,
so a `cl-assert` is not right

Correct statement about ftcr and recommend HarfBuzz

* doc/lispref/frames.texi (Font and Color Parameters): Correct
statement about availability of ftcr in the presence of HarfBuzz.
Recommend HarfBuzz.

Recommend use of HarfBuzz

* etc/NEWS: Add recommendation to use HarfBuzz.

Avoid leaving artifacts when the system caret is used on w32

* src/xdisp.c (try_window_reusing_current_matrix, try_window_id):
* src/dispnew.c (scrolling_window) [HAVE_NTGUI]: If
w32-use-visible-system-caret is non-nil, disallow scrolling the
display are in scroll_run_hook.  This avoids copying traces of the
caret, about which Emacs knows nothing, and thus considers those
pixels show the default background.  (Bug#39188)
(gui_update_window_end): Block input only around part of the code,
as we did before this code was extracted from backend-specific
implementations.

* src/w32term.c (w32_update_window_begin, w32_update_window_end):
Only hide/show the caret when redisplaying the window where the
caret is shown.

Improve display of temporary echo messages

* lisp/minibuffer.el (set-minibuffer-message): Fix cursor position
for the temporary display of an echo-area message when minibuffer
is active.  Ensure the message is visible even if the end of the
completion candidates presented by the likes of Icomplete mode is
not visible due to its length, under resize-mini-windows = nil.
(Bug#38457)

* lisp/progmodes/grep.el (grep-read-files-function): New var.

Also remove redundant :groups while we're here.

(grep-read-files): Use it instead of a major-mode symbol property.
(grep-read-files--default): New function.

* lisp/dired.el (dired-mode): Use `grep-read-files-function`.

; fix typo in previous commit

Add Cairo font backend info

* etc/NEWS: Add info about which font backends are available under Cairo.

* lisp/menu-bar.el: Remove desktop-save-mode from release branch (bug#37594)

; Not to be merged to master

Allow optional truncation of tab names in tab-bar and tab-line (bug#38693)

* lisp/tab-line.el (tab-line-tab-name-truncated-max): New defcustom.
(tab-line-tab-name-truncated-buffer): Use tab-line-tab-name-truncated-max
consistently with similar options in tab-bar.el.
(tab-line-tabs-limit): Remove variable.
(tab-line-tabs-window-buffers): Remove use of tab-line-tabs-limit
that was an experimental feature before horizontal scrolling was implemented.
(tab-line-close-tab-function): Rename from tab-line-close-tab-action
and allow a customizaed function as option.
(tab-line-close-tab): Call function if tab-line-close-tab-function
is customized to a function.

* lisp/tab-bar.el (tab-bar-tab-name-function): Add option
tab-bar-tab-name-truncated.
(tab-bar-tab-name-truncated-max): New defcustom.
(tab-bar-tab-name-truncated-ellipsis): New variable.
(tab-bar-tab-name-truncated): New function.

Small fixes in documentation.

* doc/emacs/dired.texi (Operating on Files): Fix name of dired-vc-rename-file.

* doc/emacs/fixit.texi (Undo): Update new values of undo limits
doubled in bug#31104.

Improve explanation of available font backends under X

* frames.texi (Font and Color Parameters): Clarify that you can't
have HarfBuzz and non-HarfBuzz at the same time for xft and cairo
font backends.

* lisp/international/mule-cmds.el (mule-cmds--prefixed-command-pch): Fix typo

Clear output data pointer on NS

* src/nsterm.m (ns_free_frame_resources): Clear the output data
pointer to prevent attempting to reuse freed resources (Bug#38748).

Merge branch 'master' of git.savannah.gnu.org:/srv/git/emacs

Unbreak the MS-Windows build

* src/w32.c (openat): New function.
* src/w32.h (openat): Add prototype.

Document cairo-related fallout to font-backend settings

* etc/NEWS: Document some of the possible adjustments required to
font settings when using Cairo.

Merge from origin/emacs-27

154cd116be (origin/emacs-27) * admin/release-process: Adapt bug numbe...
fd19282134 Fix shell-tests failures
891f7de8ed * test/lisp/simple-tests.el: Full path to Emacs binary (bu...
92f30d62c0 * lisp/tab-line.el (tab-line-auto-hscroll): Fix for long t...
dde313151d * lisp/menu-bar.el (menu-bar-options-menu): Add desktop-sa...
3543b9fad9 ; Fix a test (Bug#39067)
83f9fe44fa ; * etc/NEWS: Fix typo.
2eb0b7835d Fix shell-command-dont-erase-buffer feature
c134978a76 Remove reference to Emacs 19 from FAQ
fabf0065c5 Doc fixes in package.el

# Conflicts:
# etc/NEWS

; Merge from origin/emacs-27

The following commit was skipped:

5118394e5b Ensure that gnus-summary-attach-article finds the right ar...

Merge from origin/emacs-27

f3d30b5303 Remove some doc references to old Emacs versions
4217bc229b Fix infloop in shell.el
74b151195d Fix erc-notifications-notify for non-PRIVMSGs, broken in l...
db4436eaf9 Fix the notification action for PRIVMSG in erc-notificatio...
36a4068105 ERC: New maintainer.
2391d3f45d ; spelling fixes
e898442be3 Honor tags-case-fold-search during xref identifer completion

# Conflicts:
# etc/NEWS

* admin/release-process: Adapt bug numbers for release critical bugs.

Mention debbugs-gnu-emacs-release-blocking-reports.

Fix shell-tests failures

* test/lisp/shell-tests.el (shell-tests-completion-before-semi):
Go back to actually testing completion before semicolon.
(shell-tests-completion-after-semi): Test completion after semicolon,
correctly (bug#39075).

* lisp/progmodes/cc-cmds.el: Don't use local vars as symbols

(c--call-post-self-insert-hook-more-safely-1): Avoid `add-hook` and
`run-hooks` on local vars.  Avoid O(n^2) while we're at it.

* test/lisp/simple-tests.el: Full path to Emacs binary (bug#39067).

Work better if stat etc. are interrupted

Quit or retry if fstat, lstat, stat or openat fail with EINTR.
This should fix some bugs on platforms where accessing files via
NFS can fail that way (Bug#9256).
* src/dired.c (file_attributes):
* src/fileio.c (file_directory_p) [O_PATH]:
Use emacs_openat instead of openat.
* src/dired.c (file_attributes): Use emacs_fstatat instead of fstatat.
* src/fileio.c (barf_or_query_if_file_exists, Frename_file):
* src/filelock.c (rename_lock_file):
Use emacs_fstatat instead of lstat.
* src/fileio.c (file_directory_p, Ffile_regular_p, Ffile_modes)
(Ffile_newer_than_file_p, Fverify_visited_file_modtime)
(Fset_visited_file_modtime, auto_save_1):
* src/lread.c (Fload):
* src/sysdep.c (get_current_dir_name_or_unreachable):
Use emacs_fstatat instead of stat.
* src/sysdep.c (emacs_fstatat, emacs_openat): New functions.
(emacs_open): Redo in terms of emacs_open.

Fix drag and drop from some Qt versions

* lisp/x-dnd.el (x-dnd-handle-xdnd): Fix XdndDrop time stamp bug.
Problem and tiny change reported by Urs Fleisch (Bug#20804).
Copyright-paperwork-exempt: yes

* lisp/tab-line.el (tab-line-auto-hscroll): Fix for long tab names.

Check for nil value returned by previous-single-property-change that
happens when tab name is longer than window width.

* lisp/menu-bar.el (menu-bar-options-menu): Add desktop-save-mode (bug#37594)

* lisp/international/mule-cmds.el (universal-coding-system-argument): Rewrite

Use the new `prefix-command-*` hooks and functions so it interacts
better with other prefix commands (and with itself), and so the
pre/post-command-hook and other command-loop operations are performed
"normally".

(mule-cmds--prefixed-command-next-coding-system)
(mule-cmds--prefixed-command-last-coding-system): New vars.
(mule-cmds--prefixed-command-pch, mule-cmds--prefixed-command-echo)
(mule-cmds--prefixed-command-preserve): New functions.

; Fix a test (Bug#39067)

* test/lisp/simple-tests.el (with-shell-command-dont-erase-buffer):
Use flag -Q to prevent from loading site-lisp files.

Improve error handling in dired-change-marks

* lisp/dired.el (dired-change-marks): Signal user-error if mark
character is invalid.  Catch more invalid characters.  (Bug#29842)

Make arguments to dired-chage-marks non-optional

* lisp/dired.el (dired-change-marks): Make arguments
non-optional.  (Bug#29842)

; * etc/NEWS: Fix typo.

; * etc/NEWS: Fix typos.

Sync with Tramp 2.5.0-pre

* doc/misc/tramp.texi:  Protext Tramp x.y and Emacs x.y by @w{}.
(GVFS-based methods): Move "GNOME Online Accounts" index.
(Customizing Methods, Android shell setup, File name completion)
(Frequently Asked Questions): Fix typos.

* doc/misc/trampver.texi: Change version to "2.5.0-pre".

* lisp/net/trampver.el: Change version to "2.5.0-pre".
(inhibit-message): Don't declare.

* lisp/net/tramp.el: Bump version to 2.5.0-pre.  Require Emacs 25.1.
(tramp-debug-message): Simplify.
(tramp-message): Don't use `tramp-message-show-message'.
(tramp-with-demoted-errors, with-parsed-tramp-file-name)
(with-tramp-file-property, with-tramp-connection-property):
Adapt `declare' form.
(with-tramp-progress-reporter): Suppress progress reporter when
noninteractive.
(tramp-completion-mode, tramp-completion-mode-p): Remove.

* lisp/net/tramp-compat.el (tramp-compat-process-running-p)
(format-message): Remove compatibility code.
(tramp-compat-directory-name-p)
(tramp-compat-tramp-file-name-slots): Remove.

* lisp/net/tramp.el (tramp-debug-message, tramp-message)
(tramp-backtrace, tramp-error, tramp-error-with-buffer)
(tramp-user-error, tramp-with-demoted-errors)
(tramp-signal-hook-function):
* lisp/net/tramp-compat.el (tramp-compat-funcall)
* lisp/net/tramp-gvfs.el (tramp-dbus-function):
Add `tramp-suppress-trace' property.

* lisp/net/tramp.el (tramp-get-method-parameter)
(tramp-dissect-file-name, tramp-error, tramp-error-with-buffer)
(tramp-user-error, with-parsed-tramp-file-name)
(with-tramp-progress-reporter, tramp-file-name-handler)
(tramp-completion-file-name-handler, tramp-autoload-file-name-handler)
(tramp-register-file-name-handlers, tramp-connectable-p)
(tramp-handle-file-modes, tramp-handle-file-regular-p)
(tramp-handle-file-truename, tramp-handle-insert-directory)
(tramp-handle-load, tramp-set-file-uid-gid):
* lisp/net/tramp-adb.el (tramp-adb-file-name-handler)
(tramp-adb-handle-file-truename, tramp-adb-handle-copy-file)
(tramp-adb-handle-rename-file):
* lisp/net/tramp-archive.el (with-parsed-tramp-archive-file-name):
* lisp/net/tramp-cache.el (tramp-get-file-property, tramp-cache-print):
* lisp/net/tramp-compat.el (tramp-compat-process-running-p)
(tramp-compat-exec-path):
* lisp/net/tramp-gvfs.el (tramp-gvfs-file-name-handler)
(tramp-gvfs-dbus-byte-array-to-string)
(tramp-gvfs-do-copy-or-rename-file):
* lisp/net/tramp-rclone.el (tramp-rclone-file-name-handler)
(tramp-rclone-do-copy-or-rename-file):
* lisp/net/tramp-sh.el (tramp-sh-handle-file-truename)
(tramp-sh-handle-copy-directory, tramp-do-copy-or-rename-file)
(tramp-sh-handle-insert-directory, tramp-sh-file-name-handler)
(tramp-maybe-open-connection):
* lisp/net/tramp-smb.el (tramp-smb-file-name-handler)
(tramp-smb-handle-copy-file, tramp-smb-handle-copy-directory)
(tramp-smb-handle-copy-file, tramp-smb-handle-insert-directory)
(tramp-smb-handle-rename-file, tramp-smb-maybe-open-connection):
* lisp/net/tramp-sudoedit.el (tramp-sudoedit-file-name-handler)
(tramp-sudoedit-do-copy-or-rename-file)
(tramp-sudoedit-handle-file-truename):
Use `if-let', `when-let', `directory-name-p', `inhibit-message',
`non-essential and `cl-struct-slot-info'.  Don't use `seconds-to-time'.

* test/lisp/net/tramp-archive-tests.el (tramp-message-show-message):
Don't set.

* test/lisp/net/tramp-tests.el (inhibit-message): Don't declare.
(tramp-message-show-message): Don't set.
(tramp-test06-directory-file-name): Use `non-essential'.
(tramp-test10-write-region): Use `inhibit-message'.
(tramp-test36-vc-registered): No special handling for old Emacsen.
(tramp--test-emacs25-p): Remove.
(tramp-test45-unload): Special case of `tramp-completion-mode'.

Fix shell-command-dont-erase-buffer feature

* lisp/simple.el (shell-command-dont-erase-buffer):
The default, nil, is backward compatible, i.e. it erases the buffer
only if the output buffer is not the current one; the new value 'erase
always erases the output buffer.
Update docstring.

(shell-command-save-pos-or-erase):
Add optional arg output-to-current-buffer.
Rename it so that it's not internal.  All callers updated.

(shell-command-set-point-after-cmd): Rename it so that it's not internal.
All callers updated.
Adjust it to cover a side case.

(shell-command): Adjust logic to match the specification (Bug#39067).
Enable the feature when the output buffer is the current one.

(shell-command-on-region): Little tweak to follow
`shell-command-dont-erase-buffer' specification.

* test/lisp/simple-tests.el (with-shell-command-dont-erase-buffer):
Add helper macro.
(simple-tests-shell-command-39067)
(simple-tests-shell-command-dont-erase-buffer): Add tests.

* doc/emacs/misc.texi (Single Shell): Update manual.

* etc/NEWS (Single shell commands): Announce the change.

Remove Gnulib putenv code

It’s not needed, since Emacs always uses the system putenv and all
platforms have putenv.  This improves on the fix for Bug#19874.
Suggested by Bruno Haible.
* admin/merge-gnulib (GNULIB_MODULES): Remove putenv.
* configure.ac: Remove workarounds for Gnulib putenv module.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.
* lib/putenv.c, m4/putenv.m4: Remove.

Update from Gnulib

This incorporates:
2020-01-18 Rename ~~gnulib.m4 to zzgnulib.m4
2020-01-18 Fix "m4_require: circular dependency of AC_LANG_COMPILER(C)"
2020-01-18 Ensure Automake does not drop ~~gnulib.m4
2020-01-18 Fix major regression from 2020-01-10
* m4/00gnulib.m4, m4/gnulib-common.m4: Copy from Gnulib.
* m4/gnulib-comp.m4: Regenerate.
* m4/zzgnulib.m4: New file, from Gnulib.

Add space before messsage in byte compiler warnings

According to the GNU coding standards (info "(standards) Errors"):
> If you want to mention the column number, use one of these formats:
>      SOURCE-FILE-NAME:LINENO:COLUMN: MESSAGE
>      SOURCE-FILE-NAME:LINENO.COLUMN: MESSAGE

* lisp/emacs-lisp/bytecomp.el (byte-compile-warning-prefix): Add space
before message in byte compiler warnings to comply with the GNU coding
standards.  (Bug#18969)

Remove reference to Emacs 19 from FAQ

* doc/misc/efaq.texi (Emacs ignores X resources): Remove reference to
Emacs 19.

Doc fixes in package.el

* lisp/emacs-lisp/package.el (package-process-define-package)
(package-generate-description-file): Doc fixes.
(package-generate-autoloads, package--write-file-no-coding)
(package--archive-file-exists-p, package-desc-status): Add doc
strings.