1 files changed, 18 insertions, 19 deletions

diff --git a/lisp/help-mode.el b/lisp/help-mode.el
index 149eebb3d36..11656ec368c 100644
--- a/lisp/help-mode.el
+++ b/lisp/help-mode.el
@@ -147,14 +147,13 @@ The format is (FUNCTION ARGS...).")
   :supertype 'help-xref
   'help-function (lambda (fun file)
                    (require 'find-func)
+                   (when (eq file 'C-source)
+                     (setq file
+                           (help-C-file-name (indirect-function fun) 'fun)))
                    ;; Don't use find-function-noselect because it follows
                    ;; aliases (which fails for built-in functions).
                    (let ((location
-                          (cond
-                           ((bufferp file) (cons file fun))
-                           ((string-match "\\`src/\\(.*\\.c\\)" file)
-                            (help-find-C-source fun (match-string 1 file) 'fun))
-                           (t (find-function-search-for-symbol fun nil file)))))
+                          (find-function-search-for-symbol fun nil file)))
                      (pop-to-buffer (car location))
                      (goto-char (cdr location))))
   'help-echo (purecopy "mouse-2, RET: find function's definition"))
@@ -162,11 +161,9 @@ The format is (FUNCTION ARGS...).")
 (define-button-type 'help-variable-def
   :supertype 'help-xref
   'help-function (lambda (var &optional file)
-                   (let ((location
-                          (cond
-                           ((string-match "\\`src/\\(.*\\.c\\)" file)
-                            (help-find-C-source var (match-string 1 file) 'var))
-                           (t (find-variable-noselect var file)))))
+                   (when (eq file 'C-source)
+                     (setq file (help-C-file-name var 'var)))
+                   (let ((location (find-variable-noselect var file)))
                      (pop-to-buffer (car location))
                      (goto-char (cdr location))))
   'help-echo (purecopy"mouse-2, RET: find variable's definition"))
@@ -195,14 +192,17 @@ Commands:
 
 ;;;###autoload
 (defun help-mode-finish ()
+  (let ((entry (assq (selected-window) view-return-to-alist)))
+        (if entry (setcdr entry (cons (selected-window)
+                                      help-return-method))
+          (setq view-return-to-alist
+                (cons (cons (selected-window) help-return-method)
+                      view-return-to-alist))))
   (when (eq major-mode 'help-mode)
     ;; View mode's read-only status of existing *Help* buffer is lost
     ;; by with-output-to-temp-buffer.
     (toggle-read-only 1)
-    (help-make-xrefs (current-buffer)))
-  (setq view-return-to-alist
-        (list (cons (selected-window) help-return-method))))
-
+    (help-make-xrefs (current-buffer))))
 
 ;; Grokking cross-reference information in doc strings and
 ;; hyperlinking it.
@@ -577,12 +577,11 @@ help buffer."
         (goto-char position)))))
 
 (defun help-go-back ()
-  "Invoke the [back] button (if any) in the Help mode buffer."
+  "Go back to previous topic in this help buffer."
   (interactive)
-  (let ((back-button (button-at (1- (point-max)))))
-    (if back-button
-        (button-activate back-button)
-      (error "No [back] button"))))
+  (if help-xref-stack
+      (help-xref-go-back (current-buffer))
+    (error "No previous help buffer.")))
 
 (defun help-do-xref (pos function args)
   "Call the help cross-reference function FUNCTION with args ARGS.