gdb_rust_pretty_printing: adapt to the changes in the layout of btree::LeafNode

Author: japaric

src/etc/gdb_rust_pretty_printing.py

@@ -322,8 +322,10 @@ def to_string(self):
     def children(self):
         (length, data_ptr) = \
             rustpp.extract_length_and_ptr_from_std_btreeset(self.__val)
-        val = GdbValue(data_ptr.get_wrapped_value().dereference()).get_child_at_index(3)
-        gdb_ptr = val.get_wrapped_value()
+        maybe_uninit_keys = GdbValue(data_ptr.get_wrapped_value().dereference()).get_child_at_index(3)
+        manually_drop_keys = maybe_uninit_keys.get_child_at_index(1)
+        keys = manually_drop_keys.get_child_at_index(0)
+        gdb_ptr = keys.get_wrapped_value()
         for index in xrange(length):
             yield (str(index), gdb_ptr[index])
 
@@ -345,9 +347,13 @@ def to_string(self):
     def children(self):
         (length, data_ptr) = \
             rustpp.extract_length_and_ptr_from_std_btreemap(self.__val)
-        keys = GdbValue(data_ptr.get_wrapped_value().dereference()).get_child_at_index(3)
+        maybe_uninit_keys = GdbValue(data_ptr.get_wrapped_value().dereference()).get_child_at_index(3)
+        manually_drop_keys = maybe_uninit_keys.get_child_at_index(1)
+        keys = manually_drop_keys.get_child_at_index(0)
         keys_ptr = keys.get_wrapped_value()
-        vals = GdbValue(data_ptr.get_wrapped_value().dereference()).get_child_at_index(4)
+        maybe_uninit_vals = GdbValue(data_ptr.get_wrapped_value().dereference()).get_child_at_index(4)
+        manually_drop_vals = maybe_uninit_vals.get_child_at_index(1)
+        vals = manually_drop_vals.get_child_at_index(0)
         vals_ptr = vals.get_wrapped_value()
         for index in xrange(length):
             yield (str(index), keys_ptr[index])