re PR c++/79129 (ICE with -fdebug-types-section starting with r240578)

	PR debug/79129
	* dwarf2out.c (generate_skeleton_bottom_up): For children with
	comdat_type_p set, just clone them, but keep the children in the
	original DIE.

	* g++.dg/debug/dwarf2/pr79129.C: New test.

From-SVN: r244955

gcc/ChangeLog

 2017-01-26  Jakub Jelinek  <jakub@redhat.com>
 
+	PR debug/79129
+	* dwarf2out.c (generate_skeleton_bottom_up): For children with
+	comdat_type_p set, just clone them, but keep the children in the
+	original DIE.
+
 	PR debug/78835
 	* dwarf2out.c (prune_unused_types): Mark all functions with DIEs
 	which have direct callers with -fvar-tracking-assignments enabled

gcc/dwarf2out.c

@@ -7918,6 +7918,19 @@ generate_skeleton_bottom_up (skeleton_chain_node *parent)
 	    add_child_die (parent->new_die, c);
 	    c = prev;
 	  }
+	else if (c->comdat_type_p)
+	  {
+	    /* This is the skeleton of earlier break_out_comdat_types
+	       type.  Clone the existing DIE, but keep the children
+	       under the original (which is in the main CU).  */
+	    dw_die_ref clone = clone_die (c);
+
+	    replace_child (c, clone, prev);
+	    generate_skeleton_ancestor_tree (parent);
+	    add_child_die (parent->new_die, c);
+	    c = clone;
+	    continue;
+	  }
 	else
 	  {
 	    /* Clone the existing DIE, move the original to the skeleton
@@ -7936,6 +7949,7 @@ generate_skeleton_bottom_up (skeleton_chain_node *parent)
 	    replace_child (c, clone, prev);
 	    generate_skeleton_ancestor_tree (parent);
 	    add_child_die (parent->new_die, c);
+	    node.old_die = clone;
 	    node.new_die = c;
 	    c = clone;
 	  }

gcc/testsuite/ChangeLog

 2017-01-26  Jakub Jelinek  <jakub@redhat.com>
 
+	PR debug/79129
+	* g++.dg/debug/dwarf2/pr79129.C: New test.
+
 	PR debug/78835
 	* g++.dg/debug/dwarf2/pr78835.C: New test.
 

gcc/testsuite/g++.dg/debug/dwarf2/pr79129.C

+/* PR debug/79129 */
+/* { dg-do compile } */
+/* { dg-options "-gdwarf-4 -O2 -fdebug-types-section" } */
+
+struct B
+{
+  struct A { void foo (int &); };
+  A *bar ();
+  ~B () { int a = 1; bar ()->foo (a); }
+};
+struct C { ~C (); B c; };
+C::~C () {}