bpo-18748: io.IOBase destructor now logs close() errors in dev mode (GH-12786)

In development mode (-X dev) and in debug build, the io.IOBase
destructor now logs close() exceptions. These exceptions are silent
by default in release mode.

1 files changed, 15 insertions, 3 deletions

diff --git a/Modules/_io/iobase.c b/Modules/_io/iobase.c
index 9b063cd..3a8f16a 100644
--- a/Modules/_io/iobase.c
+++ b/Modules/_io/iobase.c
@@ -286,10 +286,22 @@ iobase_finalize(PyObject *self)
         /* Silencing I/O errors is bad, but printing spurious tracebacks is
            equally as bad, and potentially more frequent (because of
            shutdown issues). */
-        if (res == NULL)
-            PyErr_Clear();
-        else
+        if (res == NULL) {
+#ifndef Py_DEBUG
+            const _PyCoreConfig *config = &_PyInterpreterState_GET_UNSAFE()->core_config;
+            if (config->dev_mode) {
+                PyErr_WriteUnraisable(self);
+            }
+            else {
+                PyErr_Clear();
+            }
+#else
+            PyErr_WriteUnraisable(self);
+#endif
+        }
+        else {
             Py_DECREF(res);
+        }
     }
 
     /* Restore the saved exception. */