Merge from origin/emacs-25

ca50981 Improve time zone documentation
c23c965 Prevent bootstrap autoload backup files
9344612 Disable multicolor fonts on OS X since they are not supported...
c41ce1c Capitalize “Universal Time” in documentation
10597c9 Don't use 'find-program'

6 files changed, 44 insertions, 31 deletions

diff --git a/lisp/calendar/solar.el b/lisp/calendar/solar.el
index bf8bedd599e..6fec8055319 100644
--- a/lisp/calendar/solar.el
+++ b/lisp/calendar/solar.el
@@ -173,7 +173,7 @@ delta.  At present, delta = 0.01 degrees, so the value of the variable
 ;;; End of user options.
 
 (defvar solar-sidereal-time-greenwich-midnight nil
-  "Sidereal time at Greenwich at midnight (universal time).")
+  "Sidereal time at Greenwich at midnight (Universal Time).")
 
 (defvar solar-northern-spring-or-summer-season nil
   "Non-nil if northern spring or summer and nil otherwise.
@@ -413,8 +413,8 @@ Result is in days.  For the years 1800-1987, the maximum error is
 (defun solar-ephemeris-time (time)
   "Ephemeris Time at moment TIME.
 TIME is a pair with the first component being the number of Julian centuries
-elapsed at 0 Universal Time, and the second component being the universal
-time.  For instance, the pair corresponding to November 28, 1995 at 16 UT is
+elapsed at 0 Universal Time, and the second component counting Universal Time
+hours.  For instance, the pair corresponding to November 28, 1995 at 16 UT is
 \(-0.040945 16), -0.040945 being the number of Julian centuries elapsed between
 Jan 1, 2000 at 12 UT and November 28, 1995 at 0 UT.
 
@@ -430,7 +430,7 @@ Result is in Julian centuries of ephemeris time."
   "Right ascension (in hours) and declination (in degrees) of the sun at TIME.
 TIME is a pair with the first component being the number of
 Julian centuries elapsed at 0 Universal Time, and the second
-component being the universal time.  For instance, the pair
+component counting Universal Time hours.  For instance, the pair
 corresponding to November 28, 1995 at 16 UT is (-0.040945 16),
 -0.040945 being the number of Julian centuries elapsed between
 Jan 1, 2000 at 12 UT and November 28, 1995 at 0 UT.  SUNRISE-FLAG is passed
@@ -444,7 +444,7 @@ to `solar-ecliptic-coordinates'."
   "Azimuth and height of the sun at TIME, LATITUDE, and LONGITUDE.
 TIME is a pair with the first component being the number of
 Julian centuries elapsed at 0 Universal Time, and the second
-component being the universal time.  For instance, the pair
+component counting Universal Time hours.  For instance, the pair
 corresponding to November 28, 1995 at 16 UT is (-0.040945 16),
 -0.040945 being the number of Julian centuries elapsed between
 Jan 1, 2000 at 12 UT and November 28, 1995 at 0 UT.  SUNRISE-FLAG
@@ -476,8 +476,8 @@ Sunrise if DIRECTION =-1 or sunset if =1 at LATITUDE, LONGITUDE, with midday
 being TIME.
 
 TIME is a pair with the first component being the number of Julian centuries
-elapsed at 0 Universal Time, and the second component being the universal
-time.  For instance, the pair corresponding to November 28, 1995 at 16 UT is
+elapsed at 0 Universal Time, and the second component counting Universal Time
+hours.  For instance, the pair corresponding to November 28, 1995 at 16 UT is
 \(-0.040945 16), -0.040945 being the number of Julian centuries elapsed between
 Jan 1, 2000 at 12 UT and November 28, 1995 at 0 UT.
 
@@ -522,8 +522,8 @@ Uses binary search."
 Parameters are the midday TIME and the LATITUDE, LONGITUDE of the location.
 
 TIME is a pair with the first component being the number of Julian centuries
-elapsed at 0 Universal Time, and the second component being the universal
-time.  For instance, the pair corresponding to November 28, 1995 at 16 UT is
+elapsed at 0 Universal Time, and the second component counting Universal Time
+hours.  For instance, the pair corresponding to November 28, 1995 at 16 UT is
 \(-0.040945 16), -0.040945 being the number of Julian centuries elapsed between
 Jan 1, 2000 at 12 UT and November 28, 1995 at 0 UT.
 
diff --git a/lisp/emacs-lisp/autoload.el b/lisp/emacs-lisp/autoload.el
index 1b06fb6a51d..14e584df672 100644
--- a/lisp/emacs-lisp/autoload.el
+++ b/lisp/emacs-lisp/autoload.el
@@ -251,9 +251,22 @@ If a buffer is visiting the desired autoload file, return it."
         (enable-local-eval nil))
     ;; We used to use `raw-text' to read this file, but this causes
     ;; problems when the file contains non-ASCII characters.
-    (let ((delay-mode-hooks t))
-      (find-file-noselect
-       (autoload-ensure-default-file (autoload-generated-file))))))
+    (let* ((delay-mode-hooks t)
+           (file (autoload-generated-file))
+           (file-missing (not (file-exists-p file))))
+      (when file-missing
+        (autoload-ensure-default-file file))
+      (with-current-buffer
+          (find-file-noselect
+           (autoload-ensure-file-writeable
+            file))
+        ;; block backups when the file has just been created, since
+        ;; the backups will just be the auto-generated headers.
+        ;; bug#23203
+        (when file-missing
+          (setq buffer-backed-up t)
+          (save-buffer))
+        (current-buffer)))))
 
 (defun autoload-generated-file ()
   (expand-file-name generated-autoload-file
@@ -374,21 +387,22 @@ not be relied upon."
 ;;;###autoload
 (put 'autoload-ensure-writable 'risky-local-variable t)
 
+(defun autoload-ensure-file-writeable (file)
+  ;; Probably pointless, but replaces the old AUTOGEN_VCS in lisp/Makefile,
+  ;; which was designed to handle CVSREAD=1 and equivalent.
+  (and autoload-ensure-writable
+       (let ((modes (file-modes file)))
+         (if (zerop (logand modes #o0200))
+             ;; Ignore any errors here, and let subsequent attempts
+             ;; to write the file raise any real error.
+             (ignore-errors (set-file-modes file (logior modes #o0200))))))
+  file)
+
 (defun autoload-ensure-default-file (file)
   "Make sure that the autoload file FILE exists, creating it if needed.
 If the file already exists and `autoload-ensure-writable' is non-nil,
 make it writable."
-  (if (file-exists-p file)
-      ;; Probably pointless, but replaces the old AUTOGEN_VCS in lisp/Makefile,
-      ;; which was designed to handle CVSREAD=1 and equivalent.
-      (and autoload-ensure-writable
-           (let ((modes (file-modes file)))
-             (if (zerop (logand modes #o0200))
-                 ;; Ignore any errors here, and let subsequent attempts
-                 ;; to write the file raise any real error.
-                 (ignore-errors (set-file-modes file (logior modes #o0200))))))
-    (write-region (autoload-rubric file) nil file))
-  file)
+  (write-region (autoload-rubric file) nil file))
 
 (defun autoload-insert-section-header (outbuf autoloads load-name file time)
   "Insert the section-header line,
diff --git a/lisp/gnus/gnus-art.el b/lisp/gnus/gnus-art.el
index ca475828642..94ebbdd60c7 100644
--- a/lisp/gnus/gnus-art.el
+++ b/lisp/gnus/gnus-art.el
@@ -1009,7 +1009,7 @@ on parts -- for instance, adding Vcard info to a database."
 
 (defcustom gnus-article-date-headers '(combined-lapsed)
   "A list of Date header formats to display.
-Valid formats are `ut' (universal time), `local' (local time
+Valid formats are `ut' (Universal Time), `local' (local time
 zone), `english' (readable English), `lapsed' (elapsed time),
 `combined-lapsed' (both the original date and the elapsed time),
 `original' (the original date header), `iso8601' (ISO8601
diff --git a/lisp/org/org.el b/lisp/org/org.el
index d2b48a64e45..231daa9a6a7 100644
--- a/lisp/org/org.el
+++ b/lisp/org/org.el
@@ -22674,7 +22674,7 @@ time-range, if possible.
 
 The optional ZONE is omitted or nil for Emacs local time, t for
 Universal Time, `wall' for system wall clock time, or a string as in
-`set-time-zone-rule' for a time zone rule."
+the TZ environment variable."
   (format-time-string
    format
    (apply 'encode-time
diff --git a/lisp/progmodes/project.el b/lisp/progmodes/project.el
index 9c8a88c80fc..82059c91363 100644
--- a/lisp/progmodes/project.el
+++ b/lisp/progmodes/project.el
@@ -162,7 +162,7 @@ end it with `/'.  DIR must be one of `project-roots' or
 DIRS is a list of absolute directories; it should be some
 subset of the project roots and external roots.
 
-The default implementation uses `find-program'.  PROJECT is used
+The default implementation uses `grep-find-program'.  PROJECT is used
 to find the list of ignores for each directory."
   ;; FIXME: Uniquely abbreviate the roots?
   (require 'xref)
@@ -171,7 +171,7 @@ to find the list of ignores for each directory."
           (lambda (dir)
             (let ((command
                    (format "%s %s %s -type f -print0"
-                           find-program
+                           grep-find-program
                            dir
                            (xref--find-ignores-arguments
                             (project-ignores project dir)
diff --git a/lisp/vc/add-log.el b/lisp/vc/add-log.el
index d6c1fc203db..58a4e77a602 100644
--- a/lisp/vc/add-log.el
+++ b/lisp/vc/add-log.el
@@ -583,10 +583,9 @@ Compatibility function for \\[next-error] invocations."
 ;; called add-log-time-zone-rule since it's only used from add-log-* code.
 (defvaralias 'change-log-time-zone-rule 'add-log-time-zone-rule)
 (defvar add-log-time-zone-rule nil
-  "Time zone used for calculating change log time stamps.
-It takes the same format as the TZ argument of `set-time-zone-rule'.
-If nil, use local time.
-If t, use universal time.")
+  "Time zone rule used for calculating change log time stamps.
+If nil, use local time.  If t, use Universal Time.
+If a string, interpret as the ZONE argument of `format-time-string'.")
 (put 'add-log-time-zone-rule 'safe-local-variable
      (lambda (x) (or (booleanp x) (stringp x))))