(normal-backup-enable-predicate): Return nil for files

in /tmp, regardless of temporary-file-directory.

diff --git a/lisp/files.el b/lisp/files.el
index 841332b957a26a36b8187e36476fa4841fc6fcee..045958bf9c576737cc7749a3d5d66029a8d21f2b 100644 (file)
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -2844,13 +2844,18 @@ ignored."
 
 (defun normal-backup-enable-predicate (name)
   "Default `backup-enable-predicate' function.
-Checks for files in `temporary-file-directory' or
-`small-temporary-file-directory'."
+Checks for files in `temporary-file-directory',
+`small-temporary-file-directory', and /tmp."
   (not (or (let ((comp (compare-strings temporary-file-directory 0 nil
                                        name 0 nil)))
             ;; Directory is under temporary-file-directory.
             (and (not (eq comp t))
                  (< comp (- (length temporary-file-directory)))))
+          (let ((comp (compare-strings "/tmp" 0 nil
+                                       name 0 nil)))
+            ;; Directory is under /tmp.
+            (and (not (eq comp t))
+                 (< comp (- (length "/tmp")))))
           (if small-temporary-file-directory
               (let ((comp (compare-strings small-temporary-file-directory
                                            0 nil