(forward-paragraph): If moving back we find nothing

but separator lines till buffer beg, just stay there.
Exit outer loop if at beg or end of buffer.

diff --git a/lisp/textmodes/paragraphs.el b/lisp/textmodes/paragraphs.el
index c688561701537b73e90ac7302333c5c03931b2d8..fd5edc09a7e2f388ed92a2562e6e7c03d2f549fb 100644 (file)
--- a/lisp/textmodes/paragraphs.el
+++ b/lisp/textmodes/paragraphs.el
@@ -75,35 +75,42 @@ to which the end of the previous line belongs, or the end of the buffer."
              (concat paragraph-separate "\\|^"
                      fill-prefix-regexp "[ \t]*$")
            paragraph-separate)))
-    (while (< arg 0)
+    (while (and (< arg 0) (not (bobp)))
       (if (and (not (looking-at paragraph-separate))
               (re-search-backward "^\n" (max (1- (point)) (point-min)) t))
          nil
+       ;; Move back over paragraph-separating lines.
        (forward-char -1) (beginning-of-line)
        (while (and (not (bobp)) (looking-at paragraph-separate))
          (forward-line -1))
-       (end-of-line)
-       ;; Search back for line that starts or separates paragraphs.
-       (if (if fill-prefix-regexp
-               ;; There is a fill prefix; it overrides paragraph-start.
-               (progn
-                (while (progn (beginning-of-line)
-                              (and (not (bobp))
-                                   (not (looking-at paragraph-separate))
-                                   (looking-at fill-prefix-regexp)))
-                  (forward-line -1))
-                (not (bobp)))
-             (re-search-backward paragraph-start nil t))
-           ;; Found one.
-           (progn
-             (while (and (not (eobp)) (looking-at paragraph-separate))
-               (forward-line 1))
-             (if (eq (char-after (- (point) 2)) ?\n)
-                 (forward-line -1)))
-         ;; No starter or separator line => use buffer beg.
-         (goto-char (point-min))))
+       (if (bobp)
+           nil
+         ;; Go to end of the previous (non-separating) line.
+         (end-of-line)
+         ;; Search back for line that starts or separates paragraphs.
+         (if (if fill-prefix-regexp
+                 ;; There is a fill prefix; it overrides paragraph-start.
+                 (progn
+                  (while (progn (beginning-of-line)
+                                (and (not (bobp))
+                                     (not (looking-at paragraph-separate))
+                                     (looking-at fill-prefix-regexp)))
+                    (forward-line -1))
+                  (not (bobp)))
+               (re-search-backward paragraph-start nil t))
+             ;; Found one.
+             (progn
+               ;; Move forward over paragraph separators.
+               ;; We know this cannot reach the place we started
+               ;; because we know we moved back over a non-separator.
+               (while (and (not (eobp)) (looking-at paragraph-separate))
+                 (forward-line 1))
+               (if (eq (char-after (- (point) 2)) ?\n)
+                   (forward-line -1)))
+           ;; No starter or separator line => use buffer beg.
+           (goto-char (point-min)))))
       (setq arg (1+ arg)))
-    (while (> arg 0)
+    (while (and (> arg 0) (not (eobp)))
       (beginning-of-line)
       (while (prog1 (and (not (eobp))
                         (looking-at paragraph-separate))