[python][patch] Incorporate recent libstdc++ changes, and also extrapolatenaming patch to unordered containers.

[Phil Muldoon <pmuldoon at redhat dot com>]

Hi,

As part of a continuing review and improvement of the Python 
pretty-printers over on the libstdc++ list,  Johnathan Wakely suggested 
the following changes referenced here:

http://gcc.gnu.org/ml/libstdc++/2009-03/msg00029.html

I think they are valuable, and would like to suggest we also incorporate 
them into our repository. I've incorporated his changes in this patch, 
and as per suggestion extrapolated the changes to unordered containers.

OK?

Regards

Phil

ChangeLog:

2009-03-16  Phil Muldoon  <pmuldoon@redhat.com>
                    Jonathan Wakely  <jwakely.gcc@gmail.com>

             * python/lib/gdb/libstdcxx/v6/printers.py
             (StdPointerPrinter.to_string): Account for reference 
counts of 0.
             (build_libstdcxx_dictionary): Return correct std::tr1 or std::
             name for shared_ptr, weak_ptr, unordered_map, unordered_set,
             unordered_multimap, unordered_multiset.

diff --git a/gdb/python/lib/gdb/libstdcxx/v6/printers.py b/gdb/python/lib/gdb/libstdcxx/v6/printers.py
index a719b34..bbd7bbc 100644
--- a/gdb/python/lib/gdb/libstdcxx/v6/printers.py
+++ b/gdb/python/lib/gdb/libstdcxx/v6/printers.py
@@ -27,6 +27,8 @@ class StdPointerPrinter:
         self.val = val
 
     def to_string (self):
+        if self.val['_M_refcount']['_M_pi'] == 0:
+            return '%s (empty) %s' % (self.typename, self.val['_M_ptr'])
         return '%s (count %d) %s' % (self.typename,
         self.val['_M_refcount']['_M_pi']['_M_use_count'],
         self.val['_M_ptr'])
@@ -617,14 +619,21 @@ def build_libstdcxx_dictionary ():
     pretty_printers_dict[re.compile('^std::vector<.*>$')] = StdVectorPrinter
     # vector<bool>
 
-    # These are the C++0x printers. They also exist in the standard namespace.
+    # These are the TR1 and C++0x printers.
     # For array - the default GDB pretty-printer seems reasonable.
-    pretty_printers_dict[re.compile('^std::(tr1::)?shared_ptr<.*>$')] = lambda val: StdPointerPrinter ('std::shared_ptr', val)
-    pretty_printers_dict[re.compile('^std::(tr1::)?weak_ptr<.*>$')] = lambda val: StdPointerPrinter ('std::weak_ptr', val)
-    pretty_printers_dict[re.compile('^std::(tr1::)?unordered_map<.*>$')] = lambda val: Tr1UnorderedMapPrinter ('std::tr1::unordered_map', val)
-    pretty_printers_dict[re.compile('^std::(tr1::)?unordered_set<.*>$')] = lambda val: Tr1UnorderedSetPrinter ('std::tr1::unordered_set', val)
-    pretty_printers_dict[re.compile('^std::(tr1::)?unordered_multimap<.*>$')] = lambda val: Tr1UnorderedMapPrinter ('std::tr1::unordered_multimap', val)
-    pretty_printers_dict[re.compile('^std::(tr1::)?unordered_multiset<.*>$')] = lambda val: Tr1UnorderedSetPrinter ('std::tr1::unordered_multiset', val)
+    pretty_printers_dict[re.compile('^std::shared_ptr<.*>$')] = lambda val: StdPointerPrinter ('std::shared_ptr', val)
+    pretty_printers_dict[re.compile('^std::weak_ptr<.*>$')] = lambda val: StdPointerPrinter ('std::weak_ptr', val)
+    pretty_printers_dict[re.compile('^std::unordered_map<.*>$')] = lambda val: Tr1UnorderedMapPrinter ('std::unordered_map', val)
+    pretty_printers_dict[re.compile('^std::unordered_set<.*>$')] = lambda val: Tr1UnorderedSetPrinter ('std::unordered_set', val)
+    pretty_printers_dict[re.compile('^std::unordered_multimap<.*>$')] = lambda val: Tr1UnorderedMapPrinter ('std::unordered_multimap', val)
+    pretty_printers_dict[re.compile('^std::unordered_multiset<.*>$')] = lambda val: Tr1UnorderedSetPrinter ('std::unordered_multiset', val)
+
+    pretty_printers_dict[re.compile('^std::tr1::shared_ptr<.*>$')] = lambda val: StdPointerPrinter ('std::tr1::shared_ptr', val)
+    pretty_printers_dict[re.compile('^std::tr1::weak_ptr<.*>$')] = lambda val: StdPointerPrinter ('std::tr1::weak_ptr', val)
+    pretty_printers_dict[re.compile('^std::tr1::unordered_map<.*>$')] = lambda val: Tr1UnorderedMapPrinter ('std::tr1::unordered_map', val)
+    pretty_printers_dict[re.compile('^std::tr1::unordered_set<.*>$')] = lambda val: Tr1UnorderedSetPrinter ('std::tr1::unordered_set', val)
+    pretty_printers_dict[re.compile('^std::tr1::unordered_multimap<.*>$')] = lambda val: Tr1UnorderedMapPrinter ('std::tr1::unordered_multimap', val)
+    pretty_printers_dict[re.compile('^std::tr1::unordered_multiset<.*>$')] = lambda val: Tr1UnorderedSetPrinter ('std::tr1::unordered_multiset', val)
 
 
     # Extensions.