From 47b5d284dd6aa3281f79d973e3194ab9d6990a45 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Fri, 14 Mar 2014 21:39:03 -0400
Subject: [PATCH] re PR c++/60532 (r208573 causes Firefox build failure)

	PR c++/60532
	PR c++/58678
	* search.c (get_pure_virtuals): Handle abstract dtor here.
	(dfs_get_pure_virtuals): Not here.

From-SVN: r208586
---
 gcc/cp/ChangeLog                       |  5 ++++
 gcc/cp/search.c                        | 32 +++++++++++++-------------
 gcc/testsuite/g++.dg/other/abstract6.C | 10 ++++++++
 3 files changed, 31 insertions(+), 16 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/other/abstract6.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index b752ebe914f..ca2f8c1270d 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,10 @@
 2014-03-14  Jason Merrill  <jason@redhat.com>
 
+	PR c++/60532
+	PR c++/58678
+	* search.c (get_pure_virtuals): Handle abstract dtor here.
+	(dfs_get_pure_virtuals): Not here.
+
 	PR c++/58678
 	* search.c (dfs_get_pure_virtuals): Treat the destructor of an
 	abstract class as pure.
diff --git a/gcc/cp/search.c b/gcc/cp/search.c
index 66c6df5215e..d99e18215fa 100644
--- a/gcc/cp/search.c
+++ b/gcc/cp/search.c
@@ -2096,22 +2096,6 @@ dfs_get_pure_virtuals (tree binfo, void *data)
 	if (DECL_PURE_VIRTUAL_P (BV_FN (virtuals)))
 	  vec_safe_push (CLASSTYPE_PURE_VIRTUALS (type), BV_FN (virtuals));
     }
-  /* Treat a virtual destructor in an abstract class as pure even if it
-     isn't declared as pure; there is no way it would be called through the
-     vtable except during construction, which causes undefined behavior.  */
-  if (binfo == TYPE_BINFO (type)
-      && CLASSTYPE_PURE_VIRTUALS (type)
-      && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
-    {
-      tree dtor = CLASSTYPE_DESTRUCTORS (type);
-      if (DECL_VIRTUAL_P (dtor) && !DECL_PURE_VIRTUAL_P (dtor))
-	{
-	  tree clone;
-	  DECL_PURE_VIRTUAL_P (dtor) = true;
-	  FOR_EACH_CLONE (clone, dtor)
-	    DECL_PURE_VIRTUAL_P (clone) = true;
-	}
-    }
 
   return NULL_TREE;
 }
@@ -2131,6 +2115,22 @@ get_pure_virtuals (tree type)
      which it is a primary base will contain vtable entries for the
      pure virtuals in the base class.  */
   dfs_walk_once (TYPE_BINFO (type), NULL, dfs_get_pure_virtuals, type);
+
+  /* Treat a virtual destructor in an abstract class as pure even if it
+     isn't declared as pure; there is no way it would be called through the
+     vtable except during construction, which causes undefined behavior.  */
+  if (CLASSTYPE_PURE_VIRTUALS (type)
+      && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
+    {
+      tree dtor = CLASSTYPE_DESTRUCTORS (type);
+      if (dtor && DECL_VIRTUAL_P (dtor) && !DECL_PURE_VIRTUAL_P (dtor))
+	{
+	  tree clone;
+	  DECL_PURE_VIRTUAL_P (dtor) = true;
+	  FOR_EACH_CLONE (clone, dtor)
+	    DECL_PURE_VIRTUAL_P (clone) = true;
+	}
+    }
 }
 
 /* Debug info for C++ classes can get very large; try to avoid
diff --git a/gcc/testsuite/g++.dg/other/abstract6.C b/gcc/testsuite/g++.dg/other/abstract6.C
new file mode 100644
index 00000000000..ceba1a60b6d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/other/abstract6.C
@@ -0,0 +1,10 @@
+// PR c++/60532
+
+class A
+{
+  ~A ();
+};
+class B : A
+{
+  virtual void m () = 0;
+};