re PR libstdc++/45403 (python pretty printer for std::string requires GDB 7.1)

	PR libstdc++/45403
	* python/libstdcxx/v6/printers.py: Check for lazy_string support.

From-SVN: r165163

libstdc++-v3/ChangeLog

+2010-10-08  Jonathan Wakely  <jwakely.gcc@gmail.com>
+
+	PR libstdc++/45403
+	* python/libstdcxx/v6/printers.py: Check for lazy_string support.
+
 2010-10-08  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	* include/std/future (uses_allocator<packaged_task<>,>): Add;

libstdc++-v3/python/libstdcxx/v6/printers.py

@@ -580,7 +580,9 @@ class StdStringPrinter:
         reptype = gdb.lookup_type (str (realtype) + '::_Rep').pointer ()
         header = ptr.cast(reptype) - 1
         len = header.dereference ()['_M_length']
-        return self.val['_M_dataplus']['_M_p'].lazy_string (length = len)
+        if hasattr(ptr, "lazy_string"):
+            return ptr.lazy_string (length = len)
+        return ptr.string (length = len)
 
     def display_hint (self):
         return 'string'