Improve support for irgen of references.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@72133 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGenCXX/references.cpp b/test/CodeGenCXX/references.cpp
new file mode 100644
index 0000000..26d7157
--- /dev/null
+++ b/test/CodeGenCXX/references.cpp
@@ -0,0 +1,16 @@
+// RUN: clang-cc -verify -emit-llvm -o %t %s
+
+void t1() {
+  extern int& a;
+  int b = a; 
+}
+
+void t2(int& a) {
+  int b = a;
+}
+
+int g;
+int& gr = g;
+void t3() {
+  int b = gr;
+}