Warn about self-initialization of references.

Initializing a reference with itself, e.g. "int &a = a;" seems like a
very bad idea.

llvm-svn: 162093
diff --git a/clang/test/SemaCXX/convert-to-bool.cpp b/clang/test/SemaCXX/convert-to-bool.cpp
index c9a3555..b52f11c 100644
--- a/clang/test/SemaCXX/convert-to-bool.cpp
+++ b/clang/test/SemaCXX/convert-to-bool.cpp
@@ -62,6 +62,5 @@
 
 void test_copy_init_conversions(C c) {
   A &a = c; // expected-error{{no viable conversion from 'C' to 'A'}}
-  B &b = b; // okay
+  B &b = c; // okay
 }
-