From: Roland McGrath <roland@redhat.com>
Date: Fri, 25 Sep 2009 21:52:21 +0000 (-0700)
Subject: Fix range_list/location_attr iterators to actually start at the right offset.
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=a1d2a7175846fdf951e5bc75fb346343641c7c0f;p=thirdparty%2Felfutils.git

Fix range_list/location_attr iterators to actually start at the right offset.
---

diff --git a/libdw/ChangeLog b/libdw/ChangeLog
index fea9ebd7c..c6a576c7a 100644
--- a/libdw/ChangeLog
+++ b/libdw/ChangeLog
@@ -1,3 +1,11 @@
+2009-09-25  Roland McGrath  <roland@redhat.com>
+
+	* c++/values.cc (dwarf::range_list::const_iterator::const_iterator):
+	For begin case, actually get the offset from the attribute!
+	(dwarf::location_attr::begin): Likewise.
+	* c++/dwarf (dwarf::range_list, dwarf::location_attr): Fix iterator
+	initializers accordingly.
+
 2009-09-21  Roland McGrath  <roland@redhat.com>
 
 	* c++/dwarf-knowledge.cc (expected_value_space): DW_AT_const_value can
diff --git a/libdw/c++/dwarf b/libdw/c++/dwarf
index 0760942d5..05c4af4e1 100644
--- a/libdw/c++/dwarf
+++ b/libdw/c++/dwarf
@@ -1323,7 +1323,7 @@ namespace elfutils
 	::Dwarf_CU *_m_cu;
 	ptrdiff_t _m_offset;
 
-	const_iterator (Dwarf_Attribute *, ptrdiff_t);
+	const_iterator (Dwarf_Attribute *, ptrdiff_t offset);
 
       public:
 	// Default constructor: only valid for operator=.
@@ -1496,8 +1496,9 @@ namespace elfutils
 
 	void advance ();
 
-	inline const_iterator (Dwarf_Attribute *attr, ptrdiff_t offset)
-	  : range_list::const_iterator (attr, offset), _m_block ()
+	// For end iterator.
+	inline explicit const_iterator (Dwarf_Attribute *attr)
+	  : dwarf::range_list::const_iterator (attr, 1), _m_block ()
 	{}
 
       public:
@@ -1548,7 +1549,7 @@ namespace elfutils
       const_iterator begin () const;
       inline const_iterator end () const
       {
-	return const_iterator (_m_attr.thisattr (), 1);
+	return const_iterator (_m_attr.thisattr ());
       }
 
       inline bool empty () const
diff --git a/libdw/c++/values.cc b/libdw/c++/values.cc
index 66fffc128..1c84ad4c1 100644
--- a/libdw/c++/values.cc
+++ b/libdw/c++/values.cc
@@ -379,6 +379,12 @@ dwarf::range_list::const_iterator::const_iterator (Dwarf_Attribute *attr,
 						   ptrdiff_t offset)
   : _m_base (-1), _m_begin (0), _m_end (0), _m_cu (attr->cu), _m_offset (offset)
 {
+  if (_m_offset == 0)
+    {
+      Dwarf_Word ofs;
+      xif (attr, dwarf_formudata (attr, &ofs) < 0); // XXX __libdw_formptr
+      _m_offset = ofs;
+    }
 }
 
 static bool
@@ -574,12 +580,24 @@ dwarf::location_attr::const_iterator::advance ()
 dwarf::location_attr::const_iterator
 dwarf::location_attr::begin () const
 {
-  const_iterator i (_m_attr.thisattr (), 0);
+  const_iterator i (_m_attr.thisattr ());
   if (is_list ())
-    i.advance ();
+    {
+      // XXX __libdw_formptr
+      Dwarf_Word offset;
+      xif (_m_attr.thisattr (),
+	   dwarf_formudata (_m_attr.thisattr (), &offset) < 0);
+      i._m_offset = offset;
+      i.advance ();
+    }
   else
-    xif (_m_attr.thisattr (),
-	 dwarf_formblock (_m_attr.thisattr (), &i._m_block) < 0);
+    {
+      xif (_m_attr.thisattr (),
+	   dwarf_formblock (_m_attr.thisattr (), &i._m_block) < 0);
+      i._m_base = 0;
+      i._m_end = -1;
+      i._m_offset = 0;
+    }
 
   return i;
 }
@@ -591,8 +609,12 @@ dwarf::location_attr::const_iterator::operator++ ()
     throw std::runtime_error ("incrementing end iterator");
 
   if (_m_offset == 0)
-    // Singleton, now at end.
-    _m_offset = 1;
+    {
+      // Singleton, now at end.
+      _m_offset = 1;
+      _m_block.data = NULL;
+      _m_block.length = 0;
+    }
   else
     // Advance to next list entry.
     advance ();