(command-line): Revert to previous handling of tooltip-mode.

Explain in comment why the complexity is needed.

1 files changed, 12 insertions, 1 deletions

diff --git a/lisp/startup.el b/lisp/startup.el
index cb3dae8123a..51dea85c487 100644
--- a/lisp/startup.el
+++ b/lisp/startup.el
@@ -752,7 +752,18 @@ or `CVS', and any subdirectory that contains a file named `.nosearch'."
   ;; are not set.
   (custom-reevaluate-setting 'blink-cursor-mode)
   (custom-reevaluate-setting 'normal-erase-is-backspace)
-  (custom-reevaluate-setting 'tooltip-mode)
+
+  ;; If you change the code below, you need to also change the
+  ;; corresponding code in the tooltip-mode defcustom.  The two need
+  ;; to be equivalent under all conditions, or Custom will get confused.
+  ;; We can not use `custom-reevaluate-setting' here, because it would
+  ;; load the tooltip library on systems for which that does not make sense.
+
+   (unless (or noninteractive
+               emacs-basic-display
+               (not (display-graphic-p))
+               (not (fboundp 'x-show-tip)))
+     (tooltip-mode 1))
 
   ;; Register default TTY colors for the case the terminal hasn't a
   ;; terminal init file.