Never set opaque region without an alpha channel

* src/xfns.c (x_set_alpha_background): Don't modify opaque
region if the visual has no alpha channel.

diff --git a/src/xfns.c b/src/xfns.c
index 849fa72f39fbb5a831dae0b88193dd4e1f721d46..6226f4063ac24d9099fbc319b771c59372776779 100644 (file)
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -746,6 +746,9 @@ x_set_alpha_background (struct frame *f, Lisp_Object arg, Lisp_Object oldval)
                                  f->alpha_background != 1.0);
 #endif
 
+  if (!FRAME_DISPLAY_INFO (f)->alpha_bits)
+    return;
+
   if (f->alpha_background != 1.0)
     {
       XChangeProperty (FRAME_X_DISPLAY (f),