new file mode 100644
@@ -0,0 +1,38 @@
+// { dg-do run { target c++11 } }
+// { dg-additional-options "-O2" }
+
+#include <cassert>
+
+void *
+operator new (decltype (sizeof (0)), void *p)
+{
+ return p;
+}
+
+namespace std
+{
+ template <typename T>
+ T *
+ launder (T *p)
+ {
+ return __builtin_launder (p);
+ }
+}
+
+struct A
+{
+ const int x;
+};
+
+struct B
+{
+ A a;
+};
+
+int
+main ()
+{
+ B b{{42}};
+ new (&b.a) A{666};
+ assert(std::launder(&b.a)->x == 666);
+}
new file mode 100644
@@ -0,0 +1,40 @@
+// { dg-do run { target c++11 } }
+// { dg-additional-options "-O2" }
+
+#include <cassert>
+
+void *
+operator new (decltype (sizeof (0)), void *p)
+{
+ return p;
+}
+
+namespace std
+{
+ template <typename T>
+ T *
+ launder (T *p)
+ {
+ return __builtin_launder (p);
+ }
+}
+
+struct A
+{
+ int& x;
+};
+
+struct B
+{
+ A a;
+};
+
+int
+main ()
+{
+ int x = 42;
+ B b{{x}};
+ int y = 666;
+ new (&b.a) A{y};
+ assert(std::launder(&b.a)->x == 666);
+}