--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/warn/pr81275-2.C	Thu Oct 25 07:37:49 2018 +0900
@@ -0,0 +1,165 @@
+// PR sanitizer/81875
+// { dg-do compile }
+// { dg-options "-Wreturn-type" }
+
+struct C { C (); ~C (); };
+
+int
+f1 (int a, int b)
+{
+  C f;
+  switch (a)
+    {
+    case 0:
+      switch (b)
+        {
+	case 13:
+	  return 7;
+	case 24:
+	  return 19;
+	case 25:
+	  return 0;
+	}
+      break;
+    default:
+      return 0;
+    case 9:
+      return 17;
+    }
+}	// { dg-warning "control reaches end of non-void function" }
+
+int
+f2 (int a, int b, int c, int d)
+{
+  C f;
+  switch (a)
+    {
+    case 0:
+      switch (b)
+        {
+	case 13:
+	  while (c >= 10)
+	    {
+	      if (c == d)
+		break;
+	      c--;
+	    }
+	  return 7;
+	case 29:
+	  switch (d)
+	    {
+	    case 35:
+	      break;
+	    default:
+	      return 9;
+	    }
+	  return 8;
+	case 24:
+	  do
+	    {
+	      if (c == d)
+		break;
+	      c--;
+	    }
+	  while (c >= 10);
+	  return 19;
+	case 25:
+	  for (int e = 0; e < c; ++e)
+	    if (e == d)
+	      break;
+	  return 0;
+	}
+      break;
+    default:
+      return 0;
+    case 9:
+      return 17;
+    }
+}	// { dg-warning "control reaches end of non-void function" }
+
+template <int N>
+int
+f3 (int a, int b)
+{
+  C f;
+  switch (a)
+    {
+    case 0:
+      switch (b)
+        {
+	case 13:
+	  return 7;
+	case 24:
+	  return 19;
+	case 25:
+	  return 0;
+	}
+      break;
+    default:
+      return 0;
+    case 9:
+      return 17;
+    }
+}	// { dg-warning "control reaches end of non-void function" }
+
+template <int N>
+int
+f4 (int a, int b, int c, int d)
+{
+  C f;
+  switch (a)
+    {
+    case 0:
+      switch (b)
+        {
+	case 13:
+	  while (c >= 10)
+	    {
+	      if (c == d)
+		break;
+	      c--;
+	    }
+	  return 7;
+	case 29:
+	  switch (d)
+	    {
+	    case 35:
+	      break;
+	    default:
+	      return 9;
+	    }
+	  return 8;
+	case 24:
+	  do
+	    {
+	      if (c == d)
+		break;
+	      c--;
+	    }
+	  while (c >= 10);
+	  return 19;
+	case 25:
+	  for (int e = 0; e < c; ++e)
+	    if (e == d)
+	      break;
+	  return 0;
+	}
+      break;
+    default:
+      return 0;
+    case 9:
+      return 17;
+    }
+}	// { dg-warning "control reaches end of non-void function" }
+
+int
+f5 (int a, int b)
+{
+  return f3 <0> (a, b);
+}
+
+int
+f6 (int a, int b, int c, int d)
+{
+  return f4 <2> (a, b, c, d);
+}