--- old/src/java.desktop/unix/native/common/java2d/x11/X11PMBlitLoops.c	2017-10-16 13:03:47.601452290 -0700
+++ new/src/java.desktop/unix/native/common/java2d/x11/X11PMBlitLoops.c	2017-10-16 13:03:47.445452751 -0700
@@ -60,7 +60,7 @@
         return;
     }
 
-    xgc = (GC)gc;
+    xgc = (GC)jlong_to_ptr(gc);
     if (xgc == NULL) {
         return;
     }
@@ -151,7 +151,7 @@
         return;
     }
 
-    dstGC = (GC)xgc;
+    dstGC = (GC)jlong_to_ptr(xgc);
     if (dstGC == NULL) {
         return;
     }