PR python/18285

gdb/ChangeLog:

	PR python/18285
	* NEWS: Document new gdb.XMethodWorker.get_result_type method.
	* eval.c (evaluate_subexp_standard) <OP_FUNCALL>: Handle
	EVAL_AVOID_SIDE_EFFECTS for xmethods.
	* extension-priv.h (struct extension_language_ops)
	<get_xmethod_result_type>: New member.
	* extension.c (get_xmethod_result_type): New function.
	* extension.h (get_xmethod_result_type): Declare.
	* python/py-xmethods.c (get_result_type_method_name): New static
	global.
	(py_get_result_type_method_name): Ditto.
	(gdbpy_get_xmethod_result_type): New function.
	(gdbpy_initialize_xmethods): Initialize py_get_result_type_method_name.
	* python/python-internal.h (gdbpy_get_xmethod_result_type): Declare.
	* python/python.c (python_extension_ops): Add
	gdbpy_get_xmethod_result_type.
	* python/lib/gdb/xmethod.py (XMethodWorker): Add get_result_type.
	* valarith.c (value_x_binop): Handle EVAL_AVOID_SIDE_EFFECTS for
	xmethods.
	(value_x_unop): Ditto.
	* value.c (result_type_of_xmethod): New function.
	* value.h (result_type_of_xmethod): Declare.

gdb/testsuite/ChangeLog:

	* gdb.python/py-xmethods.exp: Add ptype tests.
	* gdb.python/py-xmethods.py (E_method_char_worker): Add
	get_result_type method.

gdb/doc/ChangeLog:

	* python.texi (Xmethod API) <gdb.XMethodWorker.get_result_type>:
	Document.
	(Writing an Xmethod): Add get_result_type to example.

1 files changed, 25 insertions, 0 deletions

diff --git a/gdb/extension.c b/gdb/extension.c
index 77b62e0..dac203b 100644
--- a/gdb/extension.c
+++ b/gdb/extension.c
@@ -964,6 +964,31 @@ get_xmethod_arg_types (struct xmethod_worker *worker, int *nargs)
   return type_array;
 }
 
+/* Return the type of the result of the xmethod encapsulated in WORKER.
+   OBJECT, ARGS, NARGS are the same as for invoke_xmethod.  */
+
+struct type *
+get_xmethod_result_type (struct xmethod_worker *worker,
+			 struct value *object, struct value **args, int nargs)
+{
+  enum ext_lang_rc rc;
+  struct type *result_type;
+  const struct extension_language_defn *extlang = worker->extlang;
+
+  gdb_assert (extlang->ops->get_xmethod_arg_types != NULL);
+
+  rc = extlang->ops->get_xmethod_result_type (extlang, worker,
+					      object, args, nargs,
+					      &result_type);
+  if (rc == EXT_LANG_RC_ERROR)
+    {
+      error (_("Error while fetching result type of an xmethod worker "
+	       "defined in %s."), extlang->capitalized_name);
+    }
+
+  return result_type;
+}
+
 /* Invokes the xmethod encapsulated in WORKER and returns the result.
    The method is invoked on OBJ with arguments in the ARGS array.  NARGS is
    the length of the this array.  */