2015-02-09  Martin Liska  <mliska@suse.cz>

	* ipa-icf.c (sem_item_optimizer::register_hooks): Register hooks
	just if not yet registered.
	(ipa_icf_generate_summary): Register callgraph hooks.

	* g++.dg/ipa/pr64858.C: New test.

--- gcc/ipa-icf.c	(revision 220530)
+++ gcc/ipa-icf.c	(revision 220531)
@@ -1562,11 +1562,13 @@ sem_item_optimizer::read_summary (void)
 void
 sem_item_optimizer::register_hooks (void)
 {
-  m_cgraph_node_hooks = symtab->add_cgraph_removal_hook
-			(&sem_item_optimizer::cgraph_removal_hook, this);
-
-  m_varpool_node_hooks = symtab->add_varpool_removal_hook
-			 (&sem_item_optimizer::varpool_removal_hook, this);
+  if (!m_cgraph_node_hooks)
+    m_cgraph_node_hooks = symtab->add_cgraph_removal_hook
+			  (&sem_item_optimizer::cgraph_removal_hook, this);
+
+  if (!m_varpool_node_hooks)
+    m_varpool_node_hooks = symtab->add_varpool_removal_hook
+			   (&sem_item_optimizer::varpool_removal_hook, this);
 }
 
 /* Unregister callgraph and varpool hooks.  */
@@ -2438,6 +2440,7 @@ ipa_icf_generate_summary (void)
   if (!optimizer)
     optimizer = new sem_item_optimizer ();
 
+  optimizer->register_hooks ();
   optimizer->parse_funcs_and_vars ();
 }
 
--- gcc/testsuite/g++.dg/ipa/pr64858.C	(revision 0)
+++ gcc/testsuite/g++.dg/ipa/pr64858.C	(revision 220531)
@@ -0,0 +1,93 @@
+// { dg-do compile }
+// { dg-options "-O2 -std=gnu++11" }
+
+template <class reference_type> class A
+{
+  reference_type *m_pBody;
+public:
+  A (const A &) { m_pBody->acquire (); }
+};
+class B;
+class C
+{
+protected:
+  B *_pInterface;
+};
+template <class interface_type> class I : C
+{
+public:
+  I (interface_type *);
+};
+class B
+{
+public:
+  virtual void acquire ();
+};
+class D
+{
+protected:
+  void acquire ();
+};
+template <class Ifc1> class J : D, public Ifc1
+{
+  void
+  acquire ()
+  {
+    D::acquire ();
+  }
+};
+class K : B
+{
+};
+class L;
+class F
+{
+  A<L> m_pDocument;
+  F (A<L> const &, int &&);
+};
+class XUnoTunnel;
+class XEventTarget;
+template <class, class> class WeakImplHelper3 : D, B
+{
+  void
+  acquire ()
+  {
+    D::acquire ();
+  }
+};
+template <class> class G
+{
+public:
+  void
+  acquire ()
+  {
+    WeakImplHelper3<XUnoTunnel, XEventTarget> ();
+  }
+};
+struct H
+{
+  H ()
+      : mxAttribList (new J<B>), mxCurrentHandler (0), mxDocHandler (0),
+        mxTokenHandler (0)
+  {
+  }
+  I<J<B> > mxAttribList;
+  I<int> mxCurrentHandler;
+  I<int> mxDocHandler;
+  I<int> mxTokenHandler;
+};
+class L : public G<int>
+{
+};
+class M : public J<K>
+{
+public:
+  M ();
+};
+template <class interface_type> I<interface_type>::I (interface_type *p1)
+{
+  B *a = static_cast<B *> (static_cast<void *> (p1));
+  _pInterface = a;
+  _pInterface->acquire ();
+}
+F::F (A<L> const &p1, int &&) : m_pDocument (p1) { I<K> (new M); }