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, 9 insertions, 0 deletions

diff --git a/gdb/eval.c b/gdb/eval.c
index 9804a97..6bbd495 100644
--- a/gdb/eval.c
+++ b/gdb/eval.c
@@ -1742,6 +1742,15 @@ evaluate_subexp_standard (struct type *expect_type,
 	      return value_zero (builtin_type (exp->gdbarch)->builtin_int,
 				 not_lval);
 	    }
+	  else if (TYPE_CODE (ftype) == TYPE_CODE_XMETHOD)
+	    {
+	      struct type *return_type
+		= result_type_of_xmethod (argvec[0], nargs, argvec + 1);
+
+	      if (return_type == NULL)
+		error (_("Xmethod is missing return type."));
+	      return value_zero (return_type, not_lval);
+	    }
 	  else if (TYPE_GNU_IFUNC (ftype))
 	    return allocate_value (TYPE_TARGET_TYPE (TYPE_TARGET_TYPE (ftype)));
 	  else if (TYPE_TARGET_TYPE (ftype))