(x_scroll_bar_clear): Do nothing if frame now has no scroll bars.

diff --git a/src/xterm.c b/src/xterm.c
index 1155ba4416984ef2f8bd845ed487d10fef0a60c6..094240651ab084b41beabd98ab2e7d2d93743ffc 100644 (file)
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -3053,10 +3053,14 @@ x_scroll_bar_clear (f)
 {
   Lisp_Object bar;
 
-  for (bar = FRAME_SCROLL_BARS (f); VECTORP (bar);
-       bar = XSCROLL_BAR (bar)->next)
-    XClearArea (FRAME_X_DISPLAY (f), SCROLL_BAR_X_WINDOW (XSCROLL_BAR (bar)),
-               0, 0, 0, 0, True);
+  /* We can have scroll bars even if this is 0,
+     if we just turned off scroll bar mode.
+     But in that case we should not clear them.  */
+  if (FRAME_HAS_VERTICAL_SCROLL_BARS (f))
+    for (bar = FRAME_SCROLL_BARS (f); VECTORP (bar);
+        bar = XSCROLL_BAR (bar)->next)
+      XClearArea (FRAME_X_DISPLAY (f), SCROLL_BAR_X_WINDOW (XSCROLL_BAR (bar)),
+                 0, 0, 0, 0, True);
 }
 
 /* This processes Expose events from the menubar specific X event