'find-tag-marker-ring' is an obsolete variable (as of 25.1)

[vonavi]

Hi guys!

Once Haskell mode was compiling, I got error

'find-tag-marker-ring' is an obsolete variable (as of 25.1); use 'xref-push-marker-stack' or 'xref-pop-marker-stack' instead.

So, I prepared the following patches to fix the issue:

--- haskell-commands.el 2015-02-06 21:26:36.000000000 +0300
+++ haskell-commands-patched.el 2015-02-06 21:56:57.000000000 +0300
@@ -18,6 +18,7 @@
 ;;; Code:

 (require 'cl-lib)
+(require 'xref)
 (require 'haskell-process)
 (require 'haskell-font-lock)
 (require 'haskell-interactive-mode)
@@ -355,9 +356,9 @@
 it will always be accurate, in contrast to tags, which always
 work but are not always accurate.

-If the definition or tag is found, the location from which you
-jumped will be pushed onto `find-tag-marker-ring', so you can
-return to that position with `pop-tag-mark'."
+If the definition or tag is found, the location from which you jumped
+will be pushed onto `xref--marker-ring', so you can return to that
+position with `xref-pop-marker-stack'."
   (interactive "P")
   (let ((initial-loc (point-marker))
         (loc (haskell-mode-find-def (haskell-ident-at-point))))
@@ -365,8 +366,11 @@
         (haskell-mode-handle-generic-loc loc)
       (call-interactively 'haskell-mode-tag-find))
     (unless (equal initial-loc (point-marker))
-      ;; Store position for return with `pop-tag-mark'
-      (ring-insert find-tag-marker-ring initial-loc))))
+      (save-excursion
+        (goto-char initial-loc)
+        (set-mark-command nil)
+        ;; Store position for return with `xref-pop-marker-stack'
+        (xref-push-marker-stack)))))

 ;;;###autoload
 (defun haskell-mode-goto-loc ()
@@ -380,7 +384,7 @@
 (defun haskell-mode-goto-span (span)
   "Jump to the span, whatever file and line and column it needs
 to to get there."
-  (ring-insert find-tag-marker-ring (point-marker))
+  (xref-push-marker-stack)
   (find-file (expand-file-name (plist-get span :path)
                                (haskell-session-cabal-dir (haskell-interactive-session))))
   (goto-char (point-min))

--- inf-haskell.el  2015-02-06 22:12:08.000000000 +0300
+++ inf-haskell-patched.el  2015-02-06 22:16:06.000000000 +0300
@@ -33,6 +33,7 @@
 (require 'comint)
 (require 'shell)             ; For directory tracking.
 (require 'compile)
+(require 'xref)
 (require 'haskell-mode)
 (require 'haskell-decl-scan)
 (require 'haskell-cabal)
@@ -568,7 +569,7 @@
             (setq file (expand-file-name file)))
           ;; Push current location marker on the ring used by `find-tag'
           (require 'etags)
-          (ring-insert find-tag-marker-ring (point-marker))
+          (xref-push-marker-stack)
           (pop-to-buffer (find-file-noselect file))
           (when line
             (goto-char (point-min))

These patches should work in principle. Maybe you will find a more suitable place for (require 'xref).

Cheers.