Convert opaque type when struct definition is seen.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@45287 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/OpaqueStruct.c b/test/CodeGen/OpaqueStruct.c
new file mode 100644
index 0000000..ecf81fa
--- /dev/null
+++ b/test/CodeGen/OpaqueStruct.c
@@ -0,0 +1,12 @@
+// RUN: clang %s -emit-llvm
+typedef struct a b;
+
+b* x;
+
+struct a {
+  b* p;
+};
+
+void f() {
+  b* z = x->p;
+}