PR python/12533:

* python/py-value.c (valpy_dereference, valpy_get_address
	valpy_get_dynamic_type, valpy_lazy_string, valpy_do_cast)
	(valpy_getitem, valpy_call, valpy_binop, valpy_negative)
	(valpy_absolute, valpy_richcompare): Free intermediate values.

gdb/ChangeLog

@@ -1,3 +1,11 @@
+2012-01-03  Tom Tromey  <tromey@redhat.com>
+
+	PR python/12533:
+	* python/py-value.c (valpy_dereference, valpy_get_address
+	valpy_get_dynamic_type, valpy_lazy_string, valpy_do_cast)
+	(valpy_getitem, valpy_call, valpy_binop, valpy_negative)
+	(valpy_absolute, valpy_richcompare): Free intermediate values.
+
 2011-01-03  Joel Brobecker  <brobecker@adacore.com>
 
 	* ada-lang.c: Reformat the copyright notice.

gdb/python/py-value.c

@@ -1,6 +1,6 @@
 /* Python interface to values.
 
-   Copyright (C) 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
+   Copyright (C) 2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -174,23 +174,27 @@ preserve_python_values (struct objfile *objfile, htab_t copied_types)
 static PyObject *
 valpy_dereference (PyObject *self, PyObject *args)
 {
-  struct value *res_val = NULL;	  /* Initialize to appease gcc warning.  */
   volatile struct gdb_exception except;
+  PyObject *result = NULL;
 
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
+      struct value *res_val;
+      struct cleanup *cleanup = make_cleanup_value_free_to_mark (value_mark ());
+
       res_val = value_ind (((value_object *) self)->value);
+      result = value_to_value_object (res_val);
+      do_cleanups (cleanup);
     }
   GDB_PY_HANDLE_EXCEPTION (except);
 
-  return value_to_value_object (res_val);
+  return result;
 }
 
 /* Return "&value".  */
 static PyObject *
 valpy_get_address (PyObject *self, void *closure)
 {
-  struct value *res_val = NULL;	  /* Initialize to appease gcc warning.  */
   value_object *val_obj = (value_object *) self;
   volatile struct gdb_exception except;
 
@@ -198,15 +202,19 @@ valpy_get_address (PyObject *self, void *closure)
     {
       TRY_CATCH (except, RETURN_MASK_ALL)
 	{
+	  struct value *res_val;
+	  struct cleanup *cleanup
+	    = make_cleanup_value_free_to_mark (value_mark ());
+
 	  res_val = value_addr (val_obj->value);
+	  val_obj->address = value_to_value_object (res_val);
+	  do_cleanups (cleanup);
 	}
       if (except.reason < 0)
 	{
 	  val_obj->address = Py_None;
 	  Py_INCREF (Py_None);
 	}
-      else
-	val_obj->address = value_to_value_object (res_val);
     }
 
   Py_XINCREF (val_obj->address);
@@ -248,6 +256,7 @@ valpy_get_dynamic_type (PyObject *self, void *closure)
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
       struct value *val = obj->value;
+      struct cleanup *cleanup = make_cleanup_value_free_to_mark (value_mark ());
 
       type = value_type (val);
       CHECK_TYPEDEF (type);
@@ -277,6 +286,8 @@ valpy_get_dynamic_type (PyObject *self, void *closure)
 	  /* Re-use object's static type.  */
 	  type = NULL;
 	}
+
+      do_cleanups (cleanup);
     }
   GDB_PY_HANDLE_EXCEPTION (except);
 
@@ -311,7 +322,7 @@ valpy_lazy_string (PyObject *self, PyObject *args, PyObject *kw)
   struct value *value = ((value_object *) self)->value;
   const char *user_encoding = NULL;
   static char *keywords[] = { "encoding", "length", NULL };
-  PyObject *str_obj;
+  PyObject *str_obj = NULL;
   volatile struct gdb_exception except;
 
   if (!PyArg_ParseTupleAndKeywords (args, kw, "|s" GDB_PY_LL_ARG, keywords,
@@ -320,16 +331,20 @@ valpy_lazy_string (PyObject *self, PyObject *args, PyObject *kw)
 
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
+      struct cleanup *cleanup = make_cleanup_value_free_to_mark (value_mark ());
+
       if (TYPE_CODE (value_type (value)) == TYPE_CODE_PTR)
 	value = value_ind (value);
-    }
-  GDB_PY_HANDLE_EXCEPTION (except);
 
       str_obj = gdbpy_create_lazy_string_object (value_address (value), length,
 						 user_encoding,
 						 value_type (value));
 
-  return (PyObject *) str_obj;
+      do_cleanups (cleanup);
+    }
+  GDB_PY_HANDLE_EXCEPTION (except);
+
+  return str_obj;
 }
 
 /* Implementation of gdb.Value.string ([encoding] [, errors]
@@ -376,9 +391,8 @@ valpy_string (PyObject *self, PyObject *args, PyObject *kw)
 static PyObject *
 valpy_do_cast (PyObject *self, PyObject *args, enum exp_opcode op)
 {
-  PyObject *type_obj;
+  PyObject *type_obj, *result = NULL;
   struct type *type;
-  struct value *res_val = NULL;	  /* Initialize to appease gcc warning.  */
   volatile struct gdb_exception except;
 
   if (! PyArg_ParseTuple (args, "O", &type_obj))
@@ -395,6 +409,8 @@ valpy_do_cast (PyObject *self, PyObject *args, enum exp_opcode op)
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
       struct value *val = ((value_object *) self)->value;
+      struct value *res_val;
+      struct cleanup *cleanup = make_cleanup_value_free_to_mark (value_mark ());
 
       if (op == UNOP_DYNAMIC_CAST)
 	res_val = value_dynamic_cast (type, val);
@@ -405,10 +421,13 @@ valpy_do_cast (PyObject *self, PyObject *args, enum exp_opcode op)
 	  gdb_assert (op == UNOP_CAST);
 	  res_val = value_cast (type, val);
 	}
+
+      result = value_to_value_object (res_val);
+      do_cleanups (cleanup);
     }
   GDB_PY_HANDLE_EXCEPTION (except);
 
-  return value_to_value_object (res_val);
+  return result;
 }
 
 /* Implementation of the "cast" method.  */
@@ -451,8 +470,8 @@ valpy_getitem (PyObject *self, PyObject *key)
 {
   value_object *self_value = (value_object *) self;
   char *field = NULL;
-  struct value *res_val = NULL;
   volatile struct gdb_exception except;
+  PyObject *result = NULL;
 
   if (gdbpy_is_string (key))
     {  
@@ -464,6 +483,8 @@ valpy_getitem (PyObject *self, PyObject *key)
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
       struct value *tmp = self_value->value;
+      struct cleanup *cleanup = make_cleanup_value_free_to_mark (value_mark ());
+      struct value *res_val = NULL;
 
       if (field)
 	res_val = value_struct_elt (&tmp, NULL, field, 0, NULL);
@@ -489,12 +510,16 @@ valpy_getitem (PyObject *self, PyObject *key)
 		res_val = value_subscript (tmp, value_as_long (idx));
 	    }
 	}
+
+      if (res_val)
+	result = value_to_value_object (res_val);
+      do_cleanups (cleanup);
     }
 
   xfree (field);
   GDB_PY_HANDLE_EXCEPTION (except);
 
-  return res_val ? value_to_value_object (res_val) : NULL;
+  return result;
 }
 
 static int
@@ -510,12 +535,13 @@ valpy_setitem (PyObject *self, PyObject *key, PyObject *value)
 static PyObject *
 valpy_call (PyObject *self, PyObject *args, PyObject *keywords)
 {
-  struct value *return_value = NULL;
   Py_ssize_t args_count;
   volatile struct gdb_exception except;
   struct value *function = ((value_object *) self)->value;
   struct value **vargs = NULL;
   struct type *ftype = NULL;
+  struct value *mark = value_mark ();
+  PyObject *result = NULL;
 
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
@@ -558,11 +584,16 @@ valpy_call (PyObject *self, PyObject *args, PyObject *keywords)
 
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
+      struct cleanup *cleanup = make_cleanup_value_free_to_mark (mark);
+      struct value *return_value;
+
       return_value = call_function_by_hand (function, args_count, vargs);
+      result = value_to_value_object (return_value);
+      do_cleanups (cleanup);
     }
   GDB_PY_HANDLE_EXCEPTION (except);
 
-  return value_to_value_object (return_value);
+  return result;
 }
 
 /* Called by the Python interpreter to obtain string representation
@@ -687,12 +718,14 @@ enum valpy_opcode
 static PyObject *
 valpy_binop (enum valpy_opcode opcode, PyObject *self, PyObject *other)
 {
-  struct value *res_val = NULL;	  /* Initialize to appease gcc warning.  */
   volatile struct gdb_exception except;
+  PyObject *result = NULL;
 
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
       struct value *arg1, *arg2;
+      struct cleanup *cleanup = make_cleanup_value_free_to_mark (value_mark ());
+      struct value *res_val;
 
       /* If the gdb.Value object is the second operand, then it will be passed
 	 to us as the OTHER argument, and SELF will be an entirely different
@@ -778,10 +811,15 @@ valpy_binop (enum valpy_opcode opcode, PyObject *self, PyObject *other)
 	  res_val = value_binop (arg1, arg2, BINOP_BITWISE_XOR);
 	  break;
 	}
+
+      if (res_val)
+	result = value_to_value_object (res_val);
+
+      do_cleanups (cleanup);
     }
   GDB_PY_HANDLE_EXCEPTION (except);
 
-  return res_val ? value_to_value_object (res_val) : NULL;
+  return result;
 }
 
 static PyObject *
@@ -833,16 +871,22 @@ valpy_power (PyObject *self, PyObject *other, PyObject *unused)
 static PyObject *
 valpy_negative (PyObject *self)
 {
-  struct value *val = NULL;
   volatile struct gdb_exception except;
+  PyObject *result = NULL;
 
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
+      /* Perhaps overkill, but consistency has some virtue.  */
+      struct cleanup *cleanup = make_cleanup_value_free_to_mark (value_mark ());
+      struct value *val;
+
       val = value_neg (((value_object *) self)->value);
+      result = value_to_value_object (val);
+      do_cleanups (cleanup);
     }
   GDB_PY_HANDLE_EXCEPTION (except);
 
-  return value_to_value_object (val);
+  return result;
 }
 
 static PyObject *
@@ -860,8 +904,12 @@ valpy_absolute (PyObject *self)
 
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
+      struct cleanup *cleanup = make_cleanup_value_free_to_mark (value_mark ());
+
       if (value_less (value, value_zero (value_type (value), not_lval)))
 	isabs = 0;
+
+      do_cleanups (cleanup);
     }
   GDB_PY_HANDLE_EXCEPTION (except);
 
@@ -961,7 +1009,6 @@ static PyObject *
 valpy_richcompare (PyObject *self, PyObject *other, int op)
 {
   int result = 0;
-  struct value *value_other;
   volatile struct gdb_exception except;
 
   if (other == Py_None)
@@ -985,6 +1032,9 @@ valpy_richcompare (PyObject *self, PyObject *other, int op)
 
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
+      struct value *value_other, *mark = value_mark ();
+      struct cleanup *cleanup;
+
       value_other = convert_value_from_python (other);
       if (value_other == NULL)
 	{
@@ -992,6 +1042,8 @@ valpy_richcompare (PyObject *self, PyObject *other, int op)
 	  break;
 	}
 
+      cleanup = make_cleanup_value_free_to_mark (mark);
+
       switch (op) {
         case Py_LT:
 	  result = value_less (((value_object *) self)->value, value_other);
@@ -1020,6 +1072,8 @@ valpy_richcompare (PyObject *self, PyObject *other, int op)
 	  result = -1;
 	  break;
       }
+
+      do_cleanups (cleanup);
     }
   GDB_PY_HANDLE_EXCEPTION (except);