Bug#814827:

[Timothy Pearson]

A similar crash also occurs when outputs are hotplugged.  Revised patch
attached.

Note that at least on my test machine with an HDMI display attached Xorg
starts but the display remains disabled.  It is currently unknown whether
this is a general bug in the radeon driver or something pcc64el specific.
--- xorg-server-1.18.0/randr/randr.c	2015-11-06 08:07:41.000000000 -0600
+++ xorg-server-1.18.0/randr/randr.c	2016-02-15 12:49:06.469645421 -0600
@@ -559,6 +559,9 @@
         mastersp = pScrPriv;
     }
 
+    if (!mastersp)
+        return;
+
     mastersp->changed = TRUE;
 }
 
--- xorg-server-1.18.0/randr/rroutput.c	2015-11-09 14:28:04.000000000 -0600
+++ xorg-server-1.18.0/randr/rroutput.c	2016-02-15 13:41:52.190584324 -0600
@@ -50,6 +50,10 @@
     }
 
     RRSetChanged(pScreen);
+
+    if (!mastersp)
+        return;
+
     if (configChanged)
         mastersp->configChanged = TRUE;
 }