--- a/src/video/x11/SDL_x11modes.c	Sat May 14 23:29:49 2016 -0400
+++ b/src/video/x11/SDL_x11modes.c	Fri May 20 22:14:40 2016 +0200
@@ -1070,7 +1070,7 @@
         *vdpi = data->vdpi;
     }
 
-    return data->ddpi != 0.0f ? 0 : -1;
+    return data->ddpi != 0.0f ? 0 : SDL_SetError("Couldn't get DPI");
 }
 
 int