From b0f6455feac97e41045ee394e11c24d92c370f6e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= <f4bug@amsat.org>
Date: Fri, 14 Feb 2020 01:13:01 +0100
Subject: [PATCH] hw/display/artist: Avoid drawing line when nothing to display
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Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200214001303.12873-5-f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 hw/display/artist.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/hw/display/artist.c b/hw/display/artist.c
index 97c811b35e..5492079116 100644
--- a/hw/display/artist.c
+++ b/hw/display/artist.c
@@ -579,6 +579,9 @@ static void draw_line(ARTISTState *s, int x1, int y1, int x2, int y2,
     } else {
         dy = y1 - y2;
     }
+    if (!dx || !dy) {
+        return;
+    }
 
     c1 = false;
     if (dy > dx) {