re PR c++/67184 (Missed optimization with C++11 final specifier)

/cp
2019-05-21  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/67184
	PR c++/69445
	* call.c (build_over_call): Devirtualize when the final overrider
	comes from the base.

/testsuite
2019-05-21  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/67184
	PR c++/69445
	* g++.dg/other/final3.C: New.
	* g++.dg/other/final4.C: Likewise.
	* g++.dg/other/final5.C: Likewise.

From-SVN: r271491

gcc/testsuite/g++.dg/other/final5.C

+// PR c++/69445
+// { dg-do compile { target c++11 } }
+// { dg-options "-fdump-tree-original"  }
+
+struct Base {
+  virtual void foo() const = 0;
+  virtual void bar() const {}
+};
+
+struct C final : Base {
+  void foo() const { }
+};
+
+void func(const C & c) {
+  c.bar();
+  c.foo();
+}
+
+// { dg-final { scan-tree-dump-times "OBJ_TYPE_REF" 0 "original" } }