commit f320be77ffb73e3b9e7fc98c37b8df3975d84b40
author Serhiy Storchaka <storchaka@gmail.com> Thu Jan 25 10:49:40 2018 +0200
committer INADA Naoki <methane@users.noreply.github.com> Thu Jan 25 17:49:40 2018 +0900
tree 552338f0200938249233fa4aa7b00add61965337
parent 2b822a0bb1de2612c85d8f75e3ce89eda2ac9f68

 bpo-32571: Avoid raising unneeded AttributeError and silencing it in C code (GH-5222)

Add two new private APIs: _PyObject_LookupAttr() and _PyObject_LookupAttrId()

Modules/_io/fileio.c

diff --git a/Modules/_io/fileio.c b/Modules/_io/fileio.c
index 269142c..0d5bf3b 100644
--- a/Modules/_io/fileio.c
+++ b/Modules/_io/fileio.c
@@ -1073,12 +1073,10 @@
     if (self->fd < 0)
         return PyUnicode_FromFormat("<_io.FileIO [closed]>");
 
-    nameobj = _PyObject_GetAttrId((PyObject *) self, &PyId_name);
+    if (_PyObject_LookupAttrId((PyObject *) self, &PyId_name, &nameobj) < 0) {
+        return NULL;
+    }
     if (nameobj == NULL) {
-        if (PyErr_ExceptionMatches(PyExc_AttributeError))
-            PyErr_Clear();
-        else
-            return NULL;
         res = PyUnicode_FromFormat(
             "<_io.FileIO fd=%d mode='%s' closefd=%s>",
             self->fd, mode_string(self), self->closefd ? "True" : "False");