fixed (hopefully) error in compiled form of org-babel-map-src-blocks

* lisp/ob.el (org-babel-map-src-blocks): Ensure that the file argument
  is only evaluated once.

lisp/ob.el

@@ -780,34 +780,36 @@ body ------------- string holding the body of the code block
 beg-body --------- point at the beginning of the body
 end-body --------- point at the end of the body"
   (declare (indent 1))
-  `(let ((visited-p (or (null ,file)
-			(get-file-buffer (expand-file-name ,file))))
-	 (point (point)) to-be-removed)
-     (save-window-excursion
-       (when ,file (find-file ,file))
-       (setq to-be-removed (current-buffer))
-       (goto-char (point-min))
-       (while (re-search-forward org-babel-src-block-regexp nil t)
-         (goto-char (match-beginning 0))
-	 (let ((full-block (match-string 0))
-	       (beg-block (match-beginning 0))
-	       (end-block (match-end 0))
-	       (lang (match-string 2))
-	       (beg-lang (match-beginning 2))
-	       (end-lang (match-end 2))
-	       (switches (match-string 3))
-	       (beg-switches (match-beginning 3))
-	       (end-switches (match-end 3))
-	       (header-args (match-string 4))
-	       (beg-header-args (match-beginning 4))
-	       (end-header-args (match-end 4))
-	       (body (match-string 5))
-	       (beg-body (match-beginning 5))
-	       (end-body (match-end 5)))
-	   ,@body
-	   (goto-char end-block))))
-     (unless visited-p (kill-buffer to-be-removed))
-     (goto-char point)))
+  (let ((tempvar (make-symbol "file")))
+    `(let* ((,tempvar ,file)
+	    (visited-p (or (null ,tempvar)
+			   (get-file-buffer (expand-file-name ,tempvar))))
+	    (point (point)) to-be-removed)
+       (save-window-excursion
+	 (when ,tempvar (find-file ,tempvar))
+	 (setq to-be-removed (current-buffer))
+	 (goto-char (point-min))
+	 (while (re-search-forward org-babel-src-block-regexp nil t)
+	   (goto-char (match-beginning 0))
+	   (let ((full-block (match-string 0))
+		 (beg-block (match-beginning 0))
+		 (end-block (match-end 0))
+		 (lang (match-string 2))
+		 (beg-lang (match-beginning 2))
+		 (end-lang (match-end 2))
+		 (switches (match-string 3))
+		 (beg-switches (match-beginning 3))
+		 (end-switches (match-end 3))
+		 (header-args (match-string 4))
+		 (beg-header-args (match-beginning 4))
+		 (end-header-args (match-end 4))
+		 (body (match-string 5))
+		 (beg-body (match-beginning 5))
+		 (end-body (match-end 5)))
+	     ,@body
+	     (goto-char end-block))))
+       (unless visited-p (kill-buffer to-be-removed))
+       (goto-char point))))
 
 (defvar org-file-properties)
 (defun org-babel-params-from-properties (&optional lang)