Merge remote-tracking branch 'origin/master' into athena/unstable

15 files changed, 396 insertions, 126 deletions

diff --git a/doc/emacs/custom.texi b/doc/emacs/custom.texi
index 00c8ee4f98b..acd7fb13ae1 100644
--- a/doc/emacs/custom.texi
+++ b/doc/emacs/custom.texi
@@ -1630,6 +1630,10 @@ characters are actually defined by this map.
 @item
 @vindex mode-specific-map
 @code{mode-specific-map} is for characters that follow @kbd{C-c}.
+@item
+@vindex project-prefix-map
+@code{project-prefix-map} is for characters that follow @kbd{C-x p},
+used for project-related commands (@pxref{Projects}).
 @end itemize
 
 @node Local Keymaps
diff --git a/doc/emacs/emacs.texi b/doc/emacs/emacs.texi
index 6b82aeb8234..5b6b7b7e93e 100644
--- a/doc/emacs/emacs.texi
+++ b/doc/emacs/emacs.texi
@@ -857,6 +857,12 @@ Customizing VC
 * CVS Options::           Options for CVS.
 @end ifnottex
 
+Projects
+
+* Project File Commands::   Commands for handling project files.
+* Project Buffer Commands:: Commands for handling project buffers.
+* Switching Projects::      Switching between projects.
+
 Change Logs
 
 * Change Log Commands:: Commands for editing change log files.
diff --git a/doc/emacs/maintaining.texi b/doc/emacs/maintaining.texi
index cc7415e7ad5..43ec2d4e9f2 100644
--- a/doc/emacs/maintaining.texi
+++ b/doc/emacs/maintaining.texi
@@ -1657,12 +1657,43 @@ the project back-end.  For example, the VC back-end doesn't consider
 ``ignored'' files (@pxref{VC Ignore}) to be part of the project.
 
 @menu
-* Project File Commands:: Commands for handling project files.
-* Switching Projects::    Switching between projects.
+* Project File Commands::   Commands for handling project files.
+* Project Buffer Commands:: Commands for handling project buffers.
+* Switching Projects::      Switching between projects.
 @end menu
 
 @node Project File Commands
-@subsection Project File Commands
+@subsection Project Commands That Operate on Files
+
+@table @kbd
+@item C-x p f
+Visit a file that belongs to the current project
+(@code{project-find-file}).
+@item C-x p g
+Find matches for a regexp in all files that belong to the current
+project (@code{project-find-regexp}).
+@item M-x project-search
+Interactively search for regexp matches in all files that belong to
+the current project.
+@item C-x p r
+Perform query-replace for a regexp in all files that belong to the
+current project (@code{project-query-replace-regexp}).
+@item C-x p d
+Run Dired in the current project's root directory
+(@code{project-dired}).
+@item C-x p v
+Run @code{vc-dir} in the current project's root directory
+(@code{project-vc-dir}).
+@item C-x p s
+Start an inferior shell in the current project's root directory
+(@code{project-shell}).
+@item C-x p e
+Start Eshell in the current project's root directory
+(@code{project-eshell}).
+@item C-x p c
+Run compilation in the current project's root directory
+(@code{project-compile}).
+@end table
 
   Emacs provides commands for handling project files conveniently.
 This subsection describes these commands.
@@ -1676,25 +1707,26 @@ doesn't seem to belong to a recognizable project, these commands
 prompt you for the project directory.
 
 @findex project-find-file
-  The command @code{project-find-file} is a convenient way of visiting
-files (@pxref{Visiting}) that belong to the current project.  Unlike
-@kbd{C-x C-f}, this command doesn't require to type the full file name
-of the file to visit, you can type only the file's base name (i.e.,
-omit the leading directories).  In addition, the completion candidates
-considered by the command include only the files belonging to the
-current project, and nothing else.  If there's a file name at point,
-this command offers that file as the default to visit.
+  The command @kbd{C-x p f} (@code{project-find-file}) is a convenient
+way of visiting files (@pxref{Visiting}) that belong to the current
+project.  Unlike @kbd{C-x C-f}, this command doesn't require to type
+the full file name of the file to visit, you can type only the file's
+base name (i.e., omit the leading directories).  In addition, the
+completion candidates considered by the command include only the files
+belonging to the current project, and nothing else.  If there's a file
+name at point, this command offers that file as the default to visit.
 
 @findex project-find-regexp
-  The command @code{project-find-regexp} is similar to @code{rgrep}
-(@pxref{Grep Searching}), but it searches only the files that belong
-to the current project.  The command prompts for the regular
-expression to search, and pops up an Xref mode buffer with the search
-results, where you can select a match using the Xref mode commands
-(@pxref{Xref Commands}).  When invoked with a prefix argument, this
-command additionally prompts for the base directory from which to
-start the search; this allows, for example, to limit the search only
-to project files under a certain subdirectory of the project root.
+  The command @kbd{C-x p g} (@code{project-find-regexp}) is similar to
+@code{rgrep} (@pxref{Grep Searching}), but it searches only the files
+that belong to the current project.  The command prompts for the
+regular expression to search, and pops up an Xref mode buffer with the
+search results, where you can select a match using the Xref mode
+commands (@pxref{Xref Commands}).  When invoked with a prefix
+argument, this command additionally prompts for the base directory
+from which to start the search; this allows, for example, to limit the
+search only to project files under a certain subdirectory of the
+project root.
 
 @findex project-search
   @kbd{M-x project-search} is an interactive variant of
@@ -1706,7 +1738,7 @@ matched file.  To find the rest of the matches, type @w{@kbd{M-x
 fileloop-continue @key{RET}}}.
 
 @findex project-query-replace-regexp
-  @kbd{M-x project-query-replace-regexp} is similar to
+  @kbd{C-x p r} (@code{project-query-replace-regexp}) is similar to
 @code{project-search}, but it prompts you for whether to replace each
 match it finds, like @code{query-replace} does (@pxref{Query
 Replace}), and continues to the next match after you respond.  If your
@@ -1714,40 +1746,85 @@ response causes Emacs to exit the query-replace loop, you can later
 continue with @w{@kbd{M-x fileloop-continue @key{RET}}}.
 
 @findex project-dired
-  The command @code{project-dired} opens a Dired buffer
-(@pxref{Dired}) listing the files in the current project's root
+  The command @kbd{C-x p d} (@code{project-dired}) opens a Dired
+buffer (@pxref{Dired}) listing the files in the current project's root
 directory.
 
 @findex project-vc-dir
-  The command @code{project-vc-dir} opens a VC Directory buffer
-(@pxref{VC Directory Mode}) listing the version control statuses of
-the files in a directory tree under the current project's
-root directory.
+  The command @kbd{C-x p v} (@code{project-vc-dir}) opens a VC
+Directory buffer (@pxref{VC Directory Mode}) listing the version
+control statuses of the files in a directory tree under the current
+project's root directory.
 
 @findex project-shell
-  The command @code{project-shell} starts a shell session
-(@pxref{Shell}) in a new buffer with the current project's root as the
-working directory.
+  The command @kbd{C-x p s} (@code{project-shell}) starts a shell
+session (@pxref{Shell}) in a new buffer with the current project's
+root as the working directory.
 
 @findex project-eshell
-  The command @code{project-eshell} starts an Eshell session in a new
-buffer with the current project's root as the working directory.
-@xref{Top,Eshell,Eshell, eshell, Eshell: The Emacs Shell}.
+  The command @kbd{C-x p e} (@code{project-eshell}) starts an Eshell
+session in a new buffer with the current project's root as the working
+directory.  @xref{Top,Eshell,Eshell, eshell, Eshell: The Emacs Shell}.
+
+@findex project-compile
+  The command @kbd{C-x p c} (@code{project-compile}) runs compilation
+(@pxref{Compilation}) in the current project's root directory.
+
+@node Project Buffer Commands
+@subsection Project Commands That Operate on Buffers
+
+@table @kbd
+@item C-x p b
+Switch to another buffer belonging to the current project
+(@code{project-switch-to-buffer}).
+@item C-x p k
+Kill all live buffers that belong to the current project
+(@code{project-kill-buffers}).
+@end table
+
+@findex project-switch-to-buffer
+  Working on a project could potentially involve having many buffers
+visiting files that belong to the project, and also buffers that
+belong to the project, but don't visit any files (like the
+@file{*compilation*} buffer created by @code{project-compile}).  The
+command @kbd{C-x p b} (@code{project-switch-to-buffer}) helps you
+switch between buffers that belong to the current project by prompting
+for a buffer to switch and considering only the current project's
+buffers as candidates for completion.
+
+@findex project-kill-buffers
+@vindex project-kill-buffers-ignores
+  When you finish working on the project, you may wish to kill all the
+buffers that belong to the project, to keep your Emacs session
+smaller.  The command @kbd{C-x p k} (@code{project-kill-buffers})
+accomplishes that: it kills all the buffers that belong to the current
+project, except if @code{project-kill-buffers-ignores} tells
+otherwise.
 
 @node Switching Projects
 @subsection Switching Projects
 
+@table @kbd
+@item C-x p p
+Run an Emacs command for another project (@code{project-switch-project}).
+@end table
+
+@findex project-switch-project
+@vindex project-switch-commands
   Commands that operate on project files (@pxref{Project File
 Commands}) will conveniently prompt you for a project directory when
-no project is current.  When you are inside a project but you want to
-operate on a different project, the command
-@code{project-switch-project} can be used.
-
-  This command prompts you to choose a directory among known project
-roots, and then displays the menu of available commands to operate on
-the chosen project.  The variable @code{project-switch-commands}
-controls which commands are available in the menu, and by which keys
-they are invoked.
+no project is current.  When you are inside some project, but you want
+to operate on a different project, use the @kbd{C-x p p} command
+(@code{project-switch-project}).  This command prompts you to choose a
+directory among known project roots, and then displays the menu of
+available commands to operate on the project you choose.  The variable
+@code{project-switch-commands} controls which commands are available
+in the menu, and which key invokes each command.
+
+@vindex project-list-file
+  The variable @code{project-list-file} names the file in which Emacs
+records the list of known projects.  It defaults to the file
+@file{projects} in @code{user-emacs-directory} (@pxref{Find Init}).
 
 @node Change Log
 @section Change Logs
diff --git a/etc/NEWS b/etc/NEWS
index 7c6c9fe2620..650b95867fb 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -502,21 +502,31 @@ information, see the related entry about 'shr-browse-url' above.
 
 *** New user option 'project-vc-merge-submodules'.
 
-*** Previously used project directories are now suggested by
-all commands that prompt for a project directory.
+*** Project commands now have their own history.
+Previously used project directories are now suggested by all commands
+that prompt for a project directory.
+
++++
+*** New prefix keymap 'project-prefix-map'.
+Key sequences that invoke project-related commands start with the
+prefix 'C-x p'.  Type "C-x p C-h" to show the full list.
 
 +++
 *** New commands 'project-dired', 'project-vc-dir', 'project-shell',
 'project-eshell'.  These commands run Dired/VC-Dir and Shell/Eshell in
 a project's root directory, respectively.
 
-*** New command 'project-compile', which runs compilation.
++++
+*** New command 'project-compile'.
+This command runs compilation in the current project's root
+directory.
 
 +++
 *** New command 'project-switch-project'.
 This command lets you "switch" to another project and run a project
 command chosen from a dispatch menu.
 
++++
 *** New user option 'project-list-file'.
 
 ** json.el
@@ -566,8 +576,8 @@ appropriate values for those two variables.  There are three guessing
 mechanisms so far: based on version control information of the current
 buffer's file, based on newsgroup/mail-folder name and several news
 and mail message headers in Gnus buffers, and based on IRC channel and
-server in rcirc buffers.  All mechanisms are extensible with custom
-rules, see the variables 'bug-reference-setup-from-vc-alist',
+network in rcirc and ERC buffers.  All mechanisms are extensible with
+custom rules, see the variables 'bug-reference-setup-from-vc-alist',
 'bug-reference-setup-from-mail-alist', and
 'bug-reference-setup-from-irc-alist'.
 
diff --git a/lisp/emacs-lisp/byte-opt.el b/lisp/emacs-lisp/byte-opt.el
index 194ceee176f..6f801be5457 100644
--- a/lisp/emacs-lisp/byte-opt.el
+++ b/lisp/emacs-lisp/byte-opt.el
@@ -709,6 +709,9 @@
              (integer (if integer-is-first arg1 arg2))
              (other (if integer-is-first arg2 arg1)))
         (list (if (eq integer 1) '1+ '1-) other)))
+     ;; (+ x y z) -> (+ (+ x y) z)
+     ((= (length args) 3)
+      `(+ ,(byte-optimize-plus `(+ ,(car args) ,(cadr args))) ,@(cddr args)))
      ;; not further optimized
      ((equal args (cdr form)) form)
      (t (cons '+ args)))))
@@ -737,6 +740,9 @@
        ((and (null (cdr args))
              (numberp (car args)))
         (- (car args)))
+       ;; (- x y z) -> (- (- x y) z)
+       ((= (length args) 3)
+        `(- ,(byte-optimize-minus `(- ,(car args) ,(cadr args))) ,@(cddr args)))
        ;; not further optimized
        ((equal args (cdr form)) form)
        (t (cons '- args))))))
@@ -764,6 +770,10 @@
      ((null args) 1)
      ;; (* n) -> n, where n is a number
      ((and (null (cdr args)) (numberp (car args))) (car args))
+     ;; (* x y z) -> (* (* x y) z)
+     ((= (length args) 3)
+      `(* ,(byte-optimize-multiply `(* ,(car args) ,(cadr args)))
+          ,@(cddr args)))
      ;; not further optimized
      ((equal args (cdr form)) form)
      (t (cons '* args)))))
diff --git a/lisp/emacs-lisp/eldoc.el b/lisp/emacs-lisp/eldoc.el
index 6ed5bff9f44..fcb104e5477 100644
--- a/lisp/emacs-lisp/eldoc.el
+++ b/lisp/emacs-lisp/eldoc.el
@@ -5,7 +5,7 @@
 ;; Author: Noah Friedman <friedman@splode.com>
 ;; Keywords: extensions
 ;; Created: 1995-10-06
-;; Version: 1.5.0
+;; Version: 1.6.0
 ;; Package-Requires: ((emacs "26.3"))
 
 ;; This is a GNU ELPA :core package.  Avoid functionality that is not
@@ -340,16 +340,32 @@ Also store it in `eldoc-last-message' and return that value."
          ;; for us, but do note that the last-message will be gone.
          (setq eldoc-last-message nil))))
 
-;; Decide whether now is a good time to display a message.
-(defun eldoc-display-message-p ()
-  "Return non-nil when it is appropriate to display an ElDoc message."
-  (and (eldoc-display-message-no-interference-p)
-       ;; If this-command is non-nil while running via an idle
-       ;; timer, we're still in the middle of executing a command,
-       ;; e.g. a query-replace where it would be annoying to
-       ;; overwrite the echo area.
-       (not this-command)
-       (eldoc--message-command-p last-command)))
+(defvar-local eldoc--last-request-state nil
+  "Tuple containing information about last ElDoc request.")
+(defun eldoc--request-state ()
+  "Compute information to store in `eldoc--last-request-state'."
+  (list (current-buffer) (buffer-modified-tick) (point)))
+
+(defun eldoc--request-docs-p (request-state)
+  "Return non-nil when it is appropriate to request docs.
+REQUEST-STATE is a candidate for `eldoc--last-request-state'"
+  (and
+   ;; FIXME: The original idea behind this function is to protect the
+   ;; Echo area from ElDoc interference, but since that is only one of
+   ;; the possible outlets of ElDoc, this must soon be reworked.
+   (eldoc-display-message-no-interference-p)
+   (not (and eldoc--doc-buffer
+             (get-buffer-window eldoc--doc-buffer)
+             (equal request-state
+                    (with-current-buffer
+                        eldoc--doc-buffer
+                      eldoc--last-request-state))))
+   ;; If this-command is non-nil while running via an idle
+   ;; timer, we're still in the middle of executing a command,
+   ;; e.g. a query-replace where it would be annoying to
+   ;; overwrite the echo area.
+   (not this-command)
+   (eldoc--message-command-p last-command)))
 
 
 ;; Check various conditions about the current environment that might make
@@ -400,7 +416,8 @@ so that the global value (i.e. the default value of the hook) is
 taken into account if the major mode specific function does not
 return any documentation.")
 
-(defvar eldoc--doc-buffer nil "Buffer holding latest eldoc-produced docs.")
+(defvar eldoc--doc-buffer nil "Buffer displaying latest ElDoc-produced docs.")
+
 (defun eldoc-doc-buffer (&optional interactive)
   "Get latest *eldoc* help buffer.  Interactively, display it."
   (interactive (list t))
@@ -410,6 +427,7 @@ return any documentation.")
           (setq eldoc--doc-buffer (get-buffer-create "*eldoc*")))
     (when interactive (display-buffer eldoc--doc-buffer))))
 
+
 (defun eldoc--handle-docs (docs)
   "Display multiple DOCS in echo area.
 DOCS is a list of (STRING PLIST...).  It is already sorted.
@@ -429,9 +447,12 @@ Honor most of `eldoc-echo-area-use-multiline-p'."
                       (integer val)
                       (t 1)))
          (things-reported-on)
+         (request eldoc--last-request-state)
          single-doc single-doc-sym)
       ;; Then, compose the contents of the `*eldoc*' buffer.
       (with-current-buffer (eldoc-doc-buffer)
+        ;; Set doc-buffer's `eldoc--last-request-state', too
+        (setq eldoc--last-request-state request)
         (let ((inhibit-read-only t))
           (erase-buffer) (setq buffer-read-only t)
           (local-set-key "q" 'quit-window)
@@ -741,14 +762,16 @@ should endeavour to display the docstrings eventually produced."
 (defun eldoc-print-current-symbol-info (&optional interactive)
   "Document thing at point."
   (interactive '(t))
-  (cond (interactive
-         (eldoc--invoke-strategy))
-        (t
-         (if (not (eldoc-display-message-p))
-             ;; Erase the last message if we won't display a new one.
-             (when eldoc-last-message
-               (eldoc--message nil))
+  (let ((token (eldoc--request-state)))
+    (cond (interactive
+           (eldoc--invoke-strategy))
+          ((not (eldoc--request-docs-p token))
+           ;; Erase the last message if we won't display a new one.
+           (when eldoc-last-message
+             (eldoc--message nil)))
+          (t
            (let ((non-essential t))
+             (setq eldoc--last-request-state token)
              ;; Only keep looking for the info as long as the user hasn't
              ;; requested our attention.  This also locally disables
              ;; inhibit-quit.
diff --git a/lisp/gnus/mm-decode.el b/lisp/gnus/mm-decode.el
index 96695aabfde..587c4e01b92 100644
--- a/lisp/gnus/mm-decode.el
+++ b/lisp/gnus/mm-decode.el
@@ -1680,8 +1680,14 @@ If RECURSIVE, search recursively."
 		    (t (y-or-n-p
 			(format "Decrypt (S/MIME) part? "))))
 		   (mm-view-pkcs7 parts from))
-	  (goto-char (point-min))
-	  (insert "Content-type: text/plain\n\n")
+	  ;; Normally there will be a Content-type header here, but
+	  ;; some mailers don't add that to the encrypted part, which
+	  ;; makes the subsequent re-dissection fail here.
+	  (save-restriction
+	    (mail-narrow-to-head)
+	    (unless (mail-fetch-field "content-type")
+	      (goto-char (point-max))
+	      (insert "Content-type: text/plain\n\n")))
 	  (setq parts (mm-dissect-buffer t)))))
      ((equal subtype "signed")
       (unless (and (setq protocol
diff --git a/lisp/ielm.el b/lisp/ielm.el
index 47c5158ce41..b3654b91d37 100644
--- a/lisp/ielm.el
+++ b/lisp/ielm.el
@@ -537,7 +537,9 @@ Customized bindings may be defined in `ielm-map', which currently contains:
        '(comint-replace-by-expanded-history
          ielm-complete-filename elisp-completion-at-point))
   (add-hook 'eldoc-documentation-functions
-            #'elisp-eldoc-documentation-function nil t)
+            #'elisp-eldoc-var-docstring nil t)
+  (add-hook 'eldoc-documentation-functions
+            #'elisp-eldoc-funcall nil t)
   (set (make-local-variable 'ielm-prompt-internal) ielm-prompt)
   (set (make-local-variable 'comint-prompt-read-only) ielm-prompt-read-only)
   (setq comint-get-old-input 'ielm-get-old-input)
diff --git a/lisp/man.el b/lisp/man.el
index 8a36f3ac25d..3121334c6f9 100644
--- a/lisp/man.el
+++ b/lisp/man.el
@@ -1396,7 +1396,7 @@ synchronously, PROCESS is the name of the buffer where the manpage
 command is run.  Second argument STRING is the entire string of output."
   (save-excursion
     (let ((Man-buffer (process-buffer process)))
-      (if (null (buffer-name Man-buffer)) ;; deleted buffer
+      (if (not (buffer-live-p Man-buffer)) ;; deleted buffer
 	  (set-process-buffer process nil)
 
 	(with-current-buffer Man-buffer
@@ -1430,7 +1430,7 @@ manpage command."
 	(delete-buff nil)
 	message)
 
-    (if (null (buffer-name Man-buffer)) ;; deleted buffer
+    (if (not (buffer-live-p Man-buffer)) ;; deleted buffer
 	(or (stringp process)
 	    (set-process-buffer process nil))
 
diff --git a/lisp/progmodes/bug-reference.el b/lisp/progmodes/bug-reference.el
index b88ea0af82c..c52331f84fa 100644
--- a/lisp/progmodes/bug-reference.el
+++ b/lisp/progmodes/bug-reference.el
@@ -353,38 +353,45 @@ and set it if applicable."
 
 This takes action if `bug-reference-mode' is enabled in IRC
 channels using one of Emacs' IRC clients (rcirc and ERC).
-Currently, only rcirc is supported.
+Currently, rcirc and ERC are supported.
 
 Each element has the form
 
-  (CHANNEL-REGEXP SERVER-REGEXP BUG-REGEXP URL-FORMAT)
+  (CHANNEL-REGEXP NETWORK-REGEXP BUG-REGEXP URL-FORMAT)
 
-CHANNEL-REGEXP is a regexp matched against the current mail IRC
-channel name.  SERVER-REGEXP is matched against the IRC server
-name.  If any of those matches, BUG-REGEXP is set as
+CHANNEL-REGEXP is a regexp matched against the current IRC
+channel name (e.g. #emacs).  NETWORK-REGEXP is matched against
+the IRC network name (e.g. freenode).  Both entries are optional.
+If all given entries match, BUG-REGEXP is set as
 `bug-reference-bug-regexp' and URL-FORMAT is set as
 `bug-reference-url-format'.")
 
-(defun bug-reference--maybe-setup-from-irc (channel server)
-  "Set up according to IRC CHANNEL or SERVER.
-CHANNEL is an IRC channel name and SERVER is that channel's
-server name.
+(defun bug-reference--maybe-setup-from-irc (channel network)
+  "Set up according to IRC CHANNEL or NETWORK.
+CHANNEL is an IRC channel name (or generally a target, i.e., it
+could also be a user name) and NETWORK is that channel's network
+name.
 
-If any CHANNEL-REGEXP or SERVER-REGEXP of
-`bug-reference-setup-from-irc-alist' matches CHANNEL or SERVER,
-the corresponding BUG-REGEXP and URL-FORMAT are set."
+If any `bug-reference-setup-from-irc-alist' entry's
+CHANNEL-REGEXP and NETWORK-REGEXP match CHANNEL and NETWORK, the
+corresponding BUG-REGEXP and URL-FORMAT are set."
   (catch 'setup-done
     (dolist (config bug-reference-setup-from-irc-alist)
-      (when (or
-             (and channel
-                  (car config)
-                  (string-match-p (car config) channel))
-             (and server
-                  (nth 1 config)
-                  (string-match-p (car config) server)))
-        (setq-local bug-reference-bug-regexp (nth 2 config))
-        (setq-local bug-reference-url-format (nth 3 config))
-        (throw 'setup-done t)))))
+      (let ((channel-rx (car config))
+            (network-rx (nth 1 config)))
+        (when (and
+               ;; One of both has to be given.
+               (or channel-rx network-rx)
+               ;; The args have to be set.
+               channel network)
+          (when (and
+                 (or (null channel-rx)
+                     (string-match-p channel-rx channel))
+                 (or (null network-rx)
+                     (string-match-p network-rx network)))
+            (setq-local bug-reference-bug-regexp (nth 2 config))
+            (setq-local bug-reference-url-format (nth 3 config))
+            (throw 'setup-done t)))))))
 
 (defvar rcirc-target)
 (defvar rcirc-server-buffer)
@@ -402,6 +409,18 @@ and set it if applicable."
           (with-current-buffer rcirc-server-buffer
             rcirc-server)))))
 
+(declare-function erc-format-target "erc")
+(declare-function erc-network-name "erc-networks")
+
+(defun bug-reference-try-setup-from-erc ()
+  "Try setting up `bug-reference-mode' based on ERC channel and server.
+Test each configuration in `bug-reference-setup-from-irc-alist'
+and set it if applicable."
+  (when (derived-mode-p 'erc-mode)
+    (bug-reference--maybe-setup-from-irc
+     (erc-format-target)
+     (erc-network-name))))
+
 (defun bug-reference--run-auto-setup ()
   (when (or bug-reference-mode
             bug-reference-prog-mode)
@@ -414,7 +433,8 @@ and set it if applicable."
         (catch 'setup
           (dolist (f (list #'bug-reference-try-setup-from-vc
                            #'bug-reference-try-setup-from-gnus
-                           #'bug-reference-try-setup-from-rcirc))
+                           #'bug-reference-try-setup-from-rcirc
+                           #'bug-reference-try-setup-from-erc))
             (when (funcall f)
               (throw 'setup t))))))))
 
diff --git a/lisp/progmodes/project.el b/lisp/progmodes/project.el
index a0930553bd7..5cfc6a20986 100644
--- a/lisp/progmodes/project.el
+++ b/lisp/progmodes/project.el
@@ -197,7 +197,7 @@ of the project instance object."
             pr (project--find-in-directory directory))))
     (when maybe-prompt
       (if pr
-          (project--add-to-project-list-front pr)
+          (project-remember-project pr)
         (project--remove-from-project-list directory)
         (setq pr (cons 'transient directory))))
     pr))
@@ -987,7 +987,8 @@ With some possible metadata (to be decided).")
       (pp project--list (current-buffer))
       (write-region nil nil filename nil 'silent))))
 
-(defun project--add-to-project-list-front (pr)
+;;;###autoload
+(defun project-remember-project (pr)
   "Add project PR to the front of the project list.
 Save the result in `project-list-file' if the list of projects has changed."
   (project--ensure-read-project-list)
diff --git a/lisp/vc/vc-git.el b/lisp/vc/vc-git.el
index b5cb842aeee..7f6e1db1ed7 100644
--- a/lisp/vc/vc-git.el
+++ b/lisp/vc/vc-git.el
@@ -1237,7 +1237,7 @@ log entries."
   (set (make-local-variable 'log-view-message-re)
        (if (not (memq vc-log-view-type '(long log-search with-diff)))
 	   (cadr vc-git-root-log-format)
-	 "^commit *\\([0-9a-z]+\\)"))
+	 "^commit +\\([0-9a-z]+\\)"))
   ;; Allow expanding short log entries.
   (when (memq vc-log-view-type '(short log-outgoing log-incoming mergebase))
     (setq truncate-lines t)
diff --git a/src/emacs-module.c b/src/emacs-module.c
index 3d1827c7dad..e4e7da088d7 100644
--- a/src/emacs-module.c
+++ b/src/emacs-module.c
@@ -78,6 +78,7 @@ To add a new module function, proceed as follows:
 #include "emacs-module.h"
 
 #include <stdarg.h>
+#include <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdlib.h>
@@ -154,11 +155,11 @@ struct emacs_value_frame
 /* A structure that holds an initial frame (so that the first local
    values require no dynamic allocation) and keeps track of the
    current frame.  */
-static struct emacs_value_storage
+struct emacs_value_storage
 {
   struct emacs_value_frame initial;
   struct emacs_value_frame *current;
-} global_storage;
+};
 
 
 /* Private runtime and environment members.  */
@@ -371,10 +372,57 @@ module_get_environment (struct emacs_runtime *runtime)
 }
 
 /* To make global refs (GC-protected global values) keep a hash that
-   maps global Lisp objects to reference counts.  */
+   maps global Lisp objects to 'struct module_global_reference'
+   objects.  We store the 'emacs_value' in the hash table so that it
+   is automatically garbage-collected (Bug#42482).  */
 
 static Lisp_Object Vmodule_refs_hash;
 
+/* Pseudovector type for global references.  The pseudovector tag is
+   PVEC_OTHER since these values are never printed and don't need to
+   be special-cased for garbage collection.  */
+
+struct module_global_reference {
+  /* Pseudovector header, must come first. */
+  union vectorlike_header header;
+
+  /* Holds the emacs_value for the object.  The Lisp_Object stored
+     therein must be the same as the hash key.  */
+  struct emacs_value_tag value;
+
+  /* Reference count, always positive.  */
+  ptrdiff_t refcount;
+};
+
+static struct module_global_reference *
+XMODULE_GLOBAL_REFERENCE (Lisp_Object o)
+{
+  eassert (PSEUDOVECTORP (o, PVEC_OTHER));
+  return XUNTAG (o, Lisp_Vectorlike, struct module_global_reference);
+}
+
+/* Returns whether V is a global reference.  Only used to check module
+   assertions.  If V is not a global reference, increment *N by the
+   number of global references (for debugging output).  */
+
+static bool
+module_global_reference_p (emacs_value v, ptrdiff_t *n)
+{
+  struct Lisp_Hash_Table *h = XHASH_TABLE (Vmodule_refs_hash);
+  /* Note that we can't use `hash_lookup' because V might be a local
+     reference that's identical to some global reference.  */
+  for (ptrdiff_t i = 0; i < HASH_TABLE_SIZE (h); ++i)
+    {
+      if (!EQ (HASH_KEY (h, i), Qunbound)
+          && &XMODULE_GLOBAL_REFERENCE (HASH_VALUE (h, i))->value == v)
+        return true;
+    }
+  /* Only used for debugging, so we don't care about overflow, just
+     make sure the operation is defined.  */
+  INT_ADD_WRAPV (*n, h->count, n);
+  return false;
+}
+
 static emacs_value
 module_make_global_ref (emacs_env *env, emacs_value value)
 {
@@ -383,21 +431,30 @@ module_make_global_ref (emacs_env *env, emacs_value value)
   Lisp_Object new_obj = value_to_lisp (value), hashcode;
   ptrdiff_t i = hash_lookup (h, new_obj, &hashcode);
 
+  /* Note: This approach requires the garbage collector to never move
+     objects.  */
+
   if (i >= 0)
     {
       Lisp_Object value = HASH_VALUE (h, i);
-      EMACS_INT refcount = XFIXNAT (value) + 1;
-      if (MOST_POSITIVE_FIXNUM < refcount)
+      struct module_global_reference *ref = XMODULE_GLOBAL_REFERENCE (value);
+      bool overflow = INT_ADD_WRAPV (ref->refcount, 1, &ref->refcount);
+      if (overflow)
 	overflow_error ();
-      value = make_fixed_natnum (refcount);
-      set_hash_value_slot (h, i, value);
+      return &ref->value;
     }
   else
     {
-      hash_put (h, new_obj, make_fixed_natnum (1), hashcode);
+      struct module_global_reference *ref
+        = ALLOCATE_PLAIN_PSEUDOVECTOR (struct module_global_reference,
+                                       PVEC_OTHER);
+      ref->value.v = new_obj;
+      ref->refcount = 1;
+      Lisp_Object value;
+      XSETPSEUDOVECTOR (value, ref, PVEC_OTHER);
+      hash_put (h, new_obj, value, hashcode);
+      return &ref->value;
     }
-
-  return allocate_emacs_value (env, &global_storage, new_obj);
 }
 
 static void
@@ -411,25 +468,21 @@ module_free_global_ref (emacs_env *env, emacs_value global_value)
   Lisp_Object obj = value_to_lisp (global_value);
   ptrdiff_t i = hash_lookup (h, obj, NULL);
 
-  if (i >= 0)
+  if (module_assertions)
     {
-      EMACS_INT refcount = XFIXNAT (HASH_VALUE (h, i)) - 1;
-      if (refcount > 0)
-        set_hash_value_slot (h, i, make_fixed_natnum (refcount));
-      else
-        {
-          eassert (refcount == 0);
-          hash_remove_from_table (h, obj);
-        }
+      ptrdiff_t n = 0;
+      if (! module_global_reference_p (global_value, &n))
+        module_abort ("Global value was not found in list of %"pD"d globals",
+                      n);
     }
 
-  if (module_assertions)
+  if (i >= 0)
     {
-      ptrdiff_t count = 0;
-      if (value_storage_contains_p (&global_storage, global_value, &count))
-        return;
-      module_abort ("Global value was not found in list of %"pD"d globals",
-                    count);
+      Lisp_Object value = HASH_VALUE (h, i);
+      struct module_global_reference *ref = XMODULE_GLOBAL_REFERENCE (value);
+      eassert (0 < ref->refcount);
+      if (--ref->refcount == 0)
+        hash_remove_from_table (h, obj);
     }
 }
 
@@ -1250,7 +1303,7 @@ value_to_lisp (emacs_value v)
           ++num_environments;
         }
       /* Also check global values.  */
-      if (value_storage_contains_p (&global_storage, v, &num_values))
+      if (module_global_reference_p (v, &num_values))
         goto ok;
       module_abort (("Emacs value not found in %"pD"d values "
 		     "of %"pD"d environments"),
@@ -1467,10 +1520,7 @@ module_handle_nonlocal_exit (emacs_env *env, enum nonlocal_exit type,
 void
 init_module_assertions (bool enable)
 {
-  /* If enabling module assertions, use a hidden environment for
-     storing the globals.  This environment is never freed.  */
   module_assertions = enable;
-  initialize_storage (&global_storage);
 }
 
 /* Return whether STORAGE contains VALUE.  Used to check module
diff --git a/test/data/emacs-module/mod-test.c b/test/data/emacs-module/mod-test.c
index 1e64bcd65f1..ed289d7a863 100644
--- a/test/data/emacs-module/mod-test.c
+++ b/test/data/emacs-module/mod-test.c
@@ -201,7 +201,19 @@ Fmod_test_globref_free (emacs_env *env, ptrdiff_t nargs, emacs_value args[],
   return env->intern (env, "ok");
 }
 
+/* Treat a local reference as global and free it.  Module assertions
+   should detect this case even if a global reference representing the
+   same object also exists.  */
 
+static emacs_value
+Fmod_test_globref_invalid_free (emacs_env *env, ptrdiff_t nargs,
+                                emacs_value *args, void *data)
+{
+  emacs_value local = env->make_integer (env, 9876);
+  env->make_global_ref (env, local);
+  env->free_global_ref (env, local);  /* Not allowed. */
+  return env->intern (env, "nil");
+}
 
 /* Return a copy of the argument string where every 'a' is replaced
    with 'b'.  */
@@ -306,6 +318,22 @@ Fmod_test_invalid_load (emacs_env *env, ptrdiff_t nargs, emacs_value *args,
   return invalid_stored_value;
 }
 
+/* The next function works in conjunction with the two previous ones.
+   It stows away a copy of the object created by
+   `Fmod_test_invalid_store' in a global reference.  Module assertions
+   should still detect the invalid load of the local reference.  */
+
+static emacs_value global_copy_of_invalid_stored_value;
+
+static emacs_value
+Fmod_test_invalid_store_copy (emacs_env *env, ptrdiff_t nargs,
+                              emacs_value *args, void *data)
+{
+  emacs_value local = Fmod_test_invalid_store (env, 0, NULL, NULL);
+  return global_copy_of_invalid_stored_value
+         = env->make_global_ref (env, local);
+}
+
 /* An invalid finalizer: Finalizers are run during garbage collection,
    where Lisp code can't be executed.  -module-assertions tests for
    this case.  */
@@ -678,12 +706,16 @@ emacs_module_init (struct emacs_runtime *ert)
 	 1, 1, NULL, NULL);
   DEFUN ("mod-test-globref-make", Fmod_test_globref_make, 0, 0, NULL, NULL);
   DEFUN ("mod-test-globref-free", Fmod_test_globref_free, 4, 4, NULL, NULL);
+  DEFUN ("mod-test-globref-invalid-free", Fmod_test_globref_invalid_free, 0, 0,
+         NULL, NULL);
   DEFUN ("mod-test-string-a-to-b", Fmod_test_string_a_to_b, 1, 1, NULL, NULL);
   DEFUN ("mod-test-userptr-make", Fmod_test_userptr_make, 1, 1, NULL, NULL);
   DEFUN ("mod-test-userptr-get", Fmod_test_userptr_get, 1, 1, NULL, NULL);
   DEFUN ("mod-test-vector-fill", Fmod_test_vector_fill, 2, 2, NULL, NULL);
   DEFUN ("mod-test-vector-eq", Fmod_test_vector_eq, 2, 2, NULL, NULL);
   DEFUN ("mod-test-invalid-store", Fmod_test_invalid_store, 0, 0, NULL, NULL);
+  DEFUN ("mod-test-invalid-store-copy", Fmod_test_invalid_store_copy, 0, 0,
+         NULL, NULL);
   DEFUN ("mod-test-invalid-load", Fmod_test_invalid_load, 0, 0, NULL, NULL);
   DEFUN ("mod-test-invalid-finalizer", Fmod_test_invalid_finalizer, 0, 0,
          NULL, NULL);
diff --git a/test/src/emacs-module-tests.el b/test/src/emacs-module-tests.el
index 411b4505da0..8465fd02e1e 100644
--- a/test/src/emacs-module-tests.el
+++ b/test/src/emacs-module-tests.el
@@ -272,6 +272,24 @@ must evaluate to a regular expression string."
     (mod-test-invalid-store)
     (mod-test-invalid-load)))
 
+(ert-deftest module--test-assertions--load-non-live-object-with-global-copy ()
+  "Check that -module-assertions verify that non-live objects aren't accessed.
+This differs from `module--test-assertions-load-non-live-object'
+in that it stows away a global reference.  The module assertions
+should nevertheless detect the invalid load."
+  (skip-unless (or (file-executable-p mod-test-emacs)
+                   (and (eq system-type 'windows-nt)
+                        (file-executable-p (concat mod-test-emacs ".exe")))))
+  ;; This doesn't yet cause undefined behavior.
+  (should (eq (mod-test-invalid-store-copy) 123))
+  (module--test-assertion (rx "Emacs value not found in "
+                              (+ digit) " values of "
+                              (+ digit) " environments\n")
+    ;; Storing and reloading a local value causes undefined behavior,
+    ;; which should be detected by the module assertions.
+    (mod-test-invalid-store-copy)
+    (mod-test-invalid-load)))
+
 (ert-deftest module--test-assertions--call-emacs-from-gc ()
   "Check that -module-assertions prevents calling Emacs functions
 during garbage collection."
@@ -283,6 +301,17 @@ during garbage collection."
     (mod-test-invalid-finalizer)
     (garbage-collect)))
 
+(ert-deftest module--test-assertions--globref-invalid-free ()
+  "Check that -module-assertions detects invalid freeing of a
+local reference."
+    (skip-unless (or (file-executable-p mod-test-emacs)
+                   (and (eq system-type 'windows-nt)
+                        (file-executable-p (concat mod-test-emacs ".exe")))))
+  (module--test-assertion
+      (rx "Global value was not found in list of " (+ digit) " globals")
+    (mod-test-globref-invalid-free)
+    (garbage-collect)))
+
 (ert-deftest module/describe-function-1 ()
   "Check that Bug#30163 is fixed."
   (with-temp-buffer