--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/builtin-object-size-7.c	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,71 @@
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+typedef __SIZE_TYPE__ size_t;
+extern void *malloc (size_t);
+extern void abort (void);
+
+struct A
+{
+  int i, j, k;
+  char buf[255];
+  int l, m, n, o;
+};
+
+int
+main (void)
+{
+  const size_t s = sizeof (struct A);
+  const size_t o = __builtin_offsetof (struct A, buf);
+  struct A *a = malloc (s);
+  struct A *b = malloc (o + 212);
+  if (__builtin_object_size (a->buf, 0) != s - o)
+    abort ();
+  if (__builtin_object_size (a->buf, 1) != sizeof (a->buf))
+    abort ();
+  if (__builtin_object_size (a->buf, 2) != s - o)
+    abort ();
+  if (__builtin_object_size (a->buf, 3) != sizeof (a->buf))
+    abort ();
+  if (__builtin_object_size (&a->buf[0], 0) != s - o)
+    abort ();
+  if (__builtin_object_size (&a->buf[0], 1) != sizeof (a->buf))
+    abort ();
+  if (__builtin_object_size (&a->buf[0], 2) != s - o)
+    abort ();
+  if (__builtin_object_size (&a->buf[0], 3) != sizeof (a->buf))
+    abort ();
+  if (__builtin_object_size (&a->buf[6], 0) != s - o - 6)
+    abort ();
+  if (__builtin_object_size (&a->buf[6], 1) != sizeof (a->buf) - 6)
+    abort ();
+  if (__builtin_object_size (&a->buf[6], 2) != s - o - 6)
+    abort ();
+  if (__builtin_object_size (&a->buf[6], 3) != sizeof (a->buf) - 6)
+    abort ();
+  if (__builtin_object_size (b->buf, 0) != 212)
+    abort ();
+  if (__builtin_object_size (b->buf, 1) != 212)
+    abort ();
+  if (__builtin_object_size (b->buf, 2) != 212)
+    abort ();
+  if (__builtin_object_size (b->buf, 3) != 212)
+    abort ();
+  if (__builtin_object_size (&b->buf[0], 0) != 212)
+    abort ();
+  if (__builtin_object_size (&b->buf[0], 1) != 212)
+    abort ();
+  if (__builtin_object_size (&b->buf[0], 2) != 212)
+    abort ();
+  if (__builtin_object_size (&b->buf[0], 3) != 212)
+    abort ();
+  if (__builtin_object_size (&b->buf[28], 0) != 212 - 28)
+    abort ();
+  if (__builtin_object_size (&b->buf[28], 1) != 212 - 28)
+    abort ();
+  if (__builtin_object_size (&b->buf[28], 2) != 212 - 28)
+    abort ();
+  if (__builtin_object_size (&b->buf[28], 3) != 212 - 28)
+    abort ();
+  return 0;
+}