--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/init/new47.C	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,19 @@
+// PR c++/70448
+// { dg-do compile }
+// { dg-options "-Wall" }
+
+typedef __typeof__ (sizeof 0) size_t;
+void *operator new (size_t, void *p) { return p; }
+void *operator new[] (size_t, void *p) { return p; }
+struct S { size_t s; };
+void bar (S *);
+
+void
+foo (unsigned int s)
+{
+  char t[sizeof (S) + s];
+  S *f = new (t) S;
+  bar (f);
+  f = new (t) S[1];
+  bar (f);
+}