[PATCH 07/10] Return gdbpy_ref<> from frame_info_to_frame_object

[Tom Tromey <tromey@adacore.com>]

This changes frame_info_to_frame_object to return a gdbpy_ref<>,
using the type system to convey that a new reference is always
returned.
---
 gdb/python/py-frame.c        | 28 +++++++++++-----------------
 gdb/python/py-framefilter.c  |  2 +-
 gdb/python/py-infevents.c    |  2 +-
 gdb/python/python-internal.h |  2 +-
 4 files changed, 14 insertions(+), 20 deletions(-)

diff --git a/gdb/python/py-frame.c b/gdb/python/py-frame.c
index 68c2628c297..c0defbdc7ef 100644
--- a/gdb/python/py-frame.c
+++ b/gdb/python/py-frame.c
@@ -360,7 +360,7 @@ frapy_function (PyObject *self, PyObject *args)
 /* Convert a frame_info struct to a Python Frame object.
    Sets a Python exception and returns NULL on error.  */
 
-PyObject *
+gdbpy_ref<>
 frame_info_to_frame_object (const frame_info_ptr &frame)
 {
   gdbpy_ref<frame_object> frame_obj (PyObject_New (frame_object,
@@ -393,7 +393,7 @@ frame_info_to_frame_object (const frame_info_ptr &frame)
       return gdbpy_handle_gdb_exception (nullptr, except);
     }
 
-  return (PyObject *) frame_obj.release ();
+  return gdbpy_ref<> (frame_obj.release ());
 }
 
 /* Implementation of gdb.Frame.older (self) -> gdb.Frame.
@@ -404,7 +404,6 @@ static PyObject *
 frapy_older (PyObject *self, PyObject *args)
 {
   frame_info_ptr frame, prev = NULL;
-  PyObject *prev_obj = NULL;   /* Initialize to appease gcc warning.  */
 
   try
     {
@@ -417,15 +416,13 @@ frapy_older (PyObject *self, PyObject *args)
       return gdbpy_handle_gdb_exception (nullptr, except);
     }
 
+  gdbpy_ref<> prev_obj;
   if (prev)
     prev_obj = frame_info_to_frame_object (prev);
   else
-    {
-      Py_INCREF (Py_None);
-      prev_obj = Py_None;
-    }
+    prev_obj = gdbpy_ref<>::new_reference (Py_None);
 
-  return prev_obj;
+  return prev_obj.release ();
 }
 
 /* Implementation of gdb.Frame.newer (self) -> gdb.Frame.
@@ -436,7 +433,6 @@ static PyObject *
 frapy_newer (PyObject *self, PyObject *args)
 {
   frame_info_ptr frame, next = NULL;
-  PyObject *next_obj = NULL;   /* Initialize to appease gcc warning.  */
 
   try
     {
@@ -449,15 +445,13 @@ frapy_newer (PyObject *self, PyObject *args)
       return gdbpy_handle_gdb_exception (nullptr, except);
     }
 
+  gdbpy_ref<> next_obj;
   if (next)
     next_obj = frame_info_to_frame_object (next);
   else
-    {
-      Py_INCREF (Py_None);
-      next_obj = Py_None;
-    }
+    next_obj = gdbpy_ref<>::new_reference (Py_None);
 
-  return next_obj;
+  return next_obj.release ();
 }
 
 /* Implementation of gdb.Frame.find_sal (self) -> gdb.Symtab_and_line.
@@ -660,7 +654,7 @@ frapy_static_link (PyObject *self, PyObject *args)
   if (link == nullptr)
     Py_RETURN_NONE;
 
-  return frame_info_to_frame_object (link);
+  return frame_info_to_frame_object (link).release ();
 }
 
 /* Implementation of gdb.newest_frame () -> gdb.Frame.
@@ -680,7 +674,7 @@ gdbpy_newest_frame (PyObject *self, PyObject *args)
       return gdbpy_handle_gdb_exception (nullptr, except);
     }
 
-  return frame_info_to_frame_object (frame);
+  return frame_info_to_frame_object (frame).release ();
 }
 
 /* Implementation of gdb.selected_frame () -> gdb.Frame.
@@ -700,7 +694,7 @@ gdbpy_selected_frame (PyObject *self, PyObject *args)
       return gdbpy_handle_gdb_exception (nullptr, except);
     }
 
-  return frame_info_to_frame_object (frame);
+  return frame_info_to_frame_object (frame).release ();
 }
 
 /* Implementation of gdb.stop_reason_string (Integer) -> String.
diff --git a/gdb/python/py-framefilter.c b/gdb/python/py-framefilter.c
index 7e54286abbc..26172d9f80e 100644
--- a/gdb/python/py-framefilter.c
+++ b/gdb/python/py-framefilter.c
@@ -1088,7 +1088,7 @@ static PyObject *
 bootstrap_python_frame_filters (const frame_info_ptr &frame,
 				int frame_low, int frame_high)
 {
-  gdbpy_ref<> frame_obj (frame_info_to_frame_object (frame));
+  gdbpy_ref<> frame_obj = frame_info_to_frame_object (frame);
   if (frame_obj == NULL)
     return NULL;
 
diff --git a/gdb/python/py-infevents.c b/gdb/python/py-infevents.c
index 58c29de130e..1b27987d039 100644
--- a/gdb/python/py-infevents.c
+++ b/gdb/python/py-infevents.c
@@ -68,7 +68,7 @@ create_register_changed_event_object (const frame_info_ptr &frame,
   if (event == NULL)
     return NULL;
 
-  gdbpy_ref<> frame_obj (frame_info_to_frame_object (frame));
+  gdbpy_ref<> frame_obj = frame_info_to_frame_object (frame);
   if (frame_obj == NULL)
     return NULL;
 
diff --git a/gdb/python/python-internal.h b/gdb/python/python-internal.h
index 6fa37cf85bd..0b816db196f 100644
--- a/gdb/python/python-internal.h
+++ b/gdb/python/python-internal.h
@@ -502,7 +502,7 @@ gdbpy_ref<> block_to_block_object (const struct block *block,
 				   struct objfile *objfile);
 gdbpy_ref<> value_to_value_object (struct value *v);
 gdbpy_ref<> type_to_type_object (struct type *);
-PyObject *frame_info_to_frame_object (const frame_info_ptr &frame);
+gdbpy_ref<> frame_info_to_frame_object (const frame_info_ptr &frame);
 PyObject *symtab_to_linetable_object (PyObject *symtab);
 gdbpy_ref<> pspace_to_pspace_object (struct program_space *);
 PyObject *pspy_get_printers (PyObject *, void *);

-- 
2.53.0