diff --git a/test/SemaCXX/__null.cpp b/test/SemaCXX/__null.cpp
new file mode 100644
index 0000000..cc04ebc
--- /dev/null
+++ b/test/SemaCXX/__null.cpp
@@ -0,0 +1,10 @@
+// RUN: clang %s -fsyntax-only -verify
+
+void f() {
+  int* i = __null;
+  i = __null;
+  int i2 = __null;
+
+  // Verify statically that __null is the right size
+  int a[sizeof(typeof(__null)) == sizeof(void*)? 1 : -1];
+}