--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/warn/Wplacement-new-size-6.C	Thu Oct 25 07:37:49 2018 +0900
@@ -0,0 +1,48 @@
+// { dg-do compile }
+// { dg-options "-Wno-pedantic -Wplacement-new=1" }
+
+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 Ax { char n, a []; };
+
+typedef __INT16_TYPE__ Int16;
+typedef __INT32_TYPE__ Int32;
+
+struct BAx { int i; Ax ax; };
+
+void fBx1 ()
+{
+  BAx bax1 = { 1, /* Ax = */ { 2, /* a[] = */ { 3 } } };	// { dg-error "initialization of flexible array member in a nested context" }
+
+  new (bax1.ax.a) char;     // { dg-warning "placement" }
+  new (bax1.ax.a) char[2];  // { dg-warning "placement" }
+  new (bax1.ax.a) Int16;    // { dg-warning "placement" }
+  new (bax1.ax.a) Int32;    // { dg-warning "placement" }
+}
+
+void fBx2 ()
+{
+  BAx bax2 = { 1, /* Ax = */ { 2, /* a[] = */ { 3, 4 } } };	// { dg-error "initialization of flexible array member in a nested context" }
+
+  new (bax2.ax.a) char;       // { dg-warning "placement" }
+  new (bax2.ax.a) char[2];    // { dg-warning "placement" }
+  new (bax2.ax.a) char[3];    // { dg-warning "placement" }
+  new (bax2.ax.a) Int16;      // { dg-warning "placement" }
+  new (bax2.ax.a) char[4];    // { dg-warning "placement" }
+  new (bax2.ax.a) Int32;      // { dg-warning "placement" }
+}
+
+void fBx3 ()
+{
+  BAx bax2 = { 1, /* Ax = */ { 3, /* a[] = */ { 4, 5, 6 } } };	// { dg-error "initialization of flexible array member in a nested context" }
+
+  new (bax2.ax.a) char;       // { dg-warning "placement" }
+  new (bax2.ax.a) char[2];    // { dg-warning "placement" }
+  new (bax2.ax.a) Int16;      // { dg-warning "placement" }
+  new (bax2.ax.a) char[3];    // { dg-warning "placement" }
+  new (bax2.ax.a) char[4];    // { dg-warning "placement" }
+  new (bax2.ax.a) Int32;      // { dg-warning "placement" }
+}