(x_set_frame_alpha): Do nothing if alpha is negative.

1 files changed, 3 insertions, 1 deletions

diff --git a/src/xterm.c b/src/xterm.c
index eef22a51443..2a0f783580e 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -487,7 +487,9 @@ x_set_frame_alpha (f)
   else if (INTEGERP (Vframe_alpha_lower_limit))
     alpha_min = (XINT (Vframe_alpha_lower_limit)) / 100.0;
 
-  if (alpha < 0.0 || 1.0 < alpha)
+  if (alpha < 0.0)
+    return;
+  else if (alpha > 1.0)
     alpha = 1.0;
   else if (0.0 <= alpha && alpha < alpha_min && alpha_min <= 1.0)
     alpha = alpha_min;