re PR debug/39524 (Duplicate C++ DW_TAG_variable breaking its DW_AT_location resolution)

	PR debug/39524
	* dwarf2out.c (gen_variable_die): Avoid adding duplicate declaration
	nodes.

	* g++.dg/debug/dwarf2/imported-decl-1.C: New test.

Co-Authored-By: Jakub Jelinek <jakub@redhat.com>

From-SVN: r145018

gcc/ChangeLog

+2009-03-24  Dodji Seketeli  <dodji@redhat.com>
+	    Jakub Jelinek  <jakub@redhat.com>
+
+	PR debug/39524
+	* dwarf2out.c (gen_variable_die): Avoid adding duplicate declaration
+	nodes.
+
 2009-03-23  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c/39495

gcc/dwarf2out.c

@@ -13978,6 +13978,14 @@ gen_variable_die (tree decl, tree origin, dw_die_ref context_die)
       return;
     }
 
+  /* If the compiler emitted a definition for the DECL declaration
+     and if we already emitted a DIE for it, don't emit a second
+     DIE for it again.  */
+  if (old_die
+      && declaration
+      && old_die->die_parent == context_die)
+    return;
+
   var_die = new_die (DW_TAG_variable, context_die, decl);
 
   origin_die = NULL;

gcc/testsuite/ChangeLog

+2009-03-24  Dodji Seketeli  <dodji@redhat.com>
+	    Jakub Jelinek  <jakub@redhat.com>
+
+	PR debug/39524
+	* g++.dg/debug/dwarf2/imported-decl-1.C: New test.
+
 2009-03-23  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c/39495

gcc/testsuite/g++.dg/debug/dwarf2/imported-decl-1.C

+// PR debug/39524
+// { dg-do compile }
+// { dg-options "-gdwarf-2 -dA -O0 -fno-merge-debug-strings" }
+
+namespace A
+{
+  static int var2 = 2;
+}
+
+int
+func ()
+{
+  using A::var2;
+  return var2;
+}
+
+// { dg-final { scan-assembler-times "var2\[^\n\r\]*DW_AT_name" 1 } }