@@ -116,6 +116,14 @@ def test_bytes(self):
         for s in [b"", b"Andr\xe8 Previn", b"abc", b" "*10000]:
             self.helper(s)
 
+    @support.cpython_only
+    def test_bytes_singleton(self):
+        for version in range(marshal.version + 1):
+            for sample in [b"", b"x"]:
+                new = marshal.loads(marshal.dumps(sample, version))
+                self.assertIs(new, sample)
+
+
 class ExceptionTestCase(unittest.TestCase):
     def test_exceptions(self):
         new = marshal.loads(marshal.dumps(StopIteration))
 
@@ -0,0 +1,2 @@
+:func:`marshal.load` and :func:`marshal.loads` can now get 1-byte string
+singletons. Patch by Victor Stinner.
@@ -1308,16 +1308,12 @@ r_object(RFILE *p)
                 }
                 break;
             }
-            v = PyBytes_FromStringAndSize((char *)NULL, n);
-            if (v == NULL)
-                break;
             ptr = r_string(n, p);
             if (ptr == NULL) {
-                Py_DECREF(v);
                 break;
             }
-            memcpy(PyBytes_AS_STRING(v), ptr, n);
-            retval = v;
+            // Get a singleton for 1-byte string
+            retval = PyBytes_FromStringAndSize(ptr, n);  // can be NULL
             R_REF(retval);
             break;
         }
Original file line number	Diff line number	Diff line change
@@ -0,0 +1,2 @@
	1	+ :func:`marshal.load` and :func:`marshal.loads` can now get 1-byte string
	2	+ singletons. Patch by Victor Stinner.
Original file line number	Diff line number	Diff line change
@@ -1308,16 +1308,12 @@ r_object(RFILE *p)
1308	1308	}
1309	1309	break;
1310	1310	}
1311		- v = PyBytes_FromStringAndSize((char *)NULL, n);
1312		- if (v == NULL)
1313		- break;
1314	1311	ptr = r_string(n, p);
1315	1312	if (ptr == NULL) {
1316		- Py_DECREF(v);
1317	1313	break;
1318	1314	}
1319		- memcpy(PyBytes_AS_STRING(v), ptr, n);
1320		- retval = v;
	1315	+ // Get a singleton for 1-byte string
	1316	+ retval = PyBytes_FromStringAndSize(ptr, n); // can be NULL
1321	1317	R_REF(retval);
1322	1318	break;
1323	1319	}