From 6e6eaecc6ab7c461f13e7a76fa3ab85b721242e8 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Tue, 25 Feb 2014 13:54:48 -0500
Subject: [PATCH] re PR lto/53808 (Undefined symbol when building a library
 with lto)

	PR lto/53808
	* class.c (clone_function_decl): Call note_vague_linkage_fn for
	defaulted virtual dtor.

From-SVN: r208153
---
 gcc/cp/ChangeLog                   |  4 ++++
 gcc/cp/class.c                     |  4 ++++
 gcc/testsuite/g++.dg/opt/devirt4.C | 16 ++++++++++++++++
 3 files changed, 24 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/opt/devirt4.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 7f63b8ed1613..393b213d87c6 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,9 @@
 2014-02-25  Jason Merrill  <jason@redhat.com>
 
+	PR lto/53808
+	* class.c (clone_function_decl): Call note_vague_linkage_fn for
+	defaulted virtual dtor.
+
 	DR 1286
 	PR c++/60328
 	* pt.c (get_underlying_template): Fix equivalence calculation.
diff --git a/gcc/cp/class.c b/gcc/cp/class.c
index 97a1cc27855c..e861e4d21e14 100644
--- a/gcc/cp/class.c
+++ b/gcc/cp/class.c
@@ -4582,6 +4582,10 @@ clone_function_decl (tree fn, int update_method_vec_p)
 	 destructor.  */
       if (DECL_VIRTUAL_P (fn))
 	{
+	  if (DECL_DEFAULTED_FN (fn) && flag_devirtualize)
+	    /* Make sure the destructor gets synthesized so that it can be
+	       inlined after devirtualization.  */
+	    note_vague_linkage_fn (fn);
 	  clone = build_clone (fn, deleting_dtor_identifier);
 	  if (update_method_vec_p)
 	    add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
diff --git a/gcc/testsuite/g++.dg/opt/devirt4.C b/gcc/testsuite/g++.dg/opt/devirt4.C
new file mode 100644
index 000000000000..5a24eecbd0ab
--- /dev/null
+++ b/gcc/testsuite/g++.dg/opt/devirt4.C
@@ -0,0 +1,16 @@
+// PR lto/53808
+// Devirtualization + inlining should produce a non-virtual
+// call to ~foo.
+// { dg-options "-O -fdevirtualize" }
+// { dg-final { scan-assembler "_ZN3fooD2Ev" } }
+
+struct foo {
+ virtual ~foo();
+};
+struct bar : public foo {
+ virtual void zed();
+};
+void f() {
+ foo *x(new bar);
+ delete x;
+}