re PR debug/27017 (Debug information for static local class members are not emitted)

	PR c++/27017
	* dwarf2out.c (prune_unused_types_walk_local_classes): New function.
	(prune_unused_types_walk): Call it for non-perennial local classes.
	Set die_mark to 2 if recursing on children.  If die_mark is 1 on
	entry, just set it to 2 and recurse on children, don't walk attributes
	again.

	* g++.dg/debug/dwarf2/localclass1.C: New test.
	* g++.dg/debug/dwarf2/localclass2.C: New test.

From-SVN: r141829

1 files changed, 63 insertions, 8 deletions

diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 614871e..337c22e 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -16248,6 +16248,37 @@ prune_unused_types_mark (dw_die_ref die, int dokids)
     }
 }
 
+/* For local classes, look if any static member functions were emitted
+   and if so, mark them.  */
+
+static void
+prune_unused_types_walk_local_classes (dw_die_ref die)
+{
+  dw_die_ref c;
+
+  if (die->die_mark == 2)
+    return;
+
+  switch (die->die_tag)
+    {
+    case DW_TAG_structure_type:
+    case DW_TAG_union_type:
+    case DW_TAG_class_type:
+      break;
+
+    case DW_TAG_subprogram:
+      if (!get_AT_flag (die, DW_AT_declaration)
+	  || die->die_definition != NULL)
+	prune_unused_types_mark (die, 1);
+      return;
+
+    default:
+      return;
+    }
+
+  /* Mark children.  */
+  FOR_EACH_CHILD (die, c, prune_unused_types_walk_local_classes (c));
+}
 
 /* Walk the tree DIE and mark types that we actually use.  */
 
@@ -16256,12 +16287,34 @@ prune_unused_types_walk (dw_die_ref die)
 {
   dw_die_ref c;
 
-  /* Don't do anything if this node is already marked.  */
-  if (die->die_mark)
+  /* Don't do anything if this node is already marked and
+     children have been marked as well.  */
+  if (die->die_mark == 2)
     return;
 
   switch (die->die_tag)
     {
+    case DW_TAG_structure_type:
+    case DW_TAG_union_type:
+    case DW_TAG_class_type:
+      if (die->die_perennial_p)
+	break;
+
+      for (c = die->die_parent; c; c = c->die_parent)
+	if (c->die_tag == DW_TAG_subprogram)
+	  break;
+
+      /* Finding used static member functions inside of classes
+	 is needed just for local classes, because for other classes
+	 static member function DIEs with DW_AT_specification
+	 are emitted outside of the DW_TAG_*_type.  If we ever change
+	 it, we'd need to call this even for non-local classes.  */
+      if (c)
+	prune_unused_types_walk_local_classes (die);
+
+      /* It's a type node --- don't mark it.  */
+      return;
+
     case DW_TAG_const_type:
     case DW_TAG_packed_type:
     case DW_TAG_pointer_type:
@@ -16269,9 +16322,6 @@ prune_unused_types_walk (dw_die_ref die)
     case DW_TAG_volatile_type:
     case DW_TAG_typedef:
     case DW_TAG_array_type:
-    case DW_TAG_structure_type:
-    case DW_TAG_union_type:
-    case DW_TAG_class_type:
     case DW_TAG_interface_type:
     case DW_TAG_friend:
     case DW_TAG_variant_part:
@@ -16293,10 +16343,15 @@ prune_unused_types_walk (dw_die_ref die)
       break;
   }
 
-  die->die_mark = 1;
+  if (die->die_mark == 0)
+    {
+      die->die_mark = 1;
+
+      /* Now, mark any dies referenced from here.  */
+      prune_unused_types_walk_attribs (die);
+    }
 
-  /* Now, mark any dies referenced from here.  */
-  prune_unused_types_walk_attribs (die);
+  die->die_mark = 2;
 
   /* Mark children.  */
   FOR_EACH_CHILD (die, c, prune_unused_types_walk (c));