* Backport pythongh-78214: marshal: Stabilize FLAG_REF usage. Closes: #1010368.

Author: doko42

debian/changelog

@@ -1,3 +1,10 @@
+python3.10 (3.10.4-4) unstable; urgency=medium
+
+  * Source-only upload.
+  * Backport gh-78214: marshal: Stabilize FLAG_REF usage. Closes: #1010368.
+
+ -- Matthias Klose <doko@debian.org>  Fri, 13 May 2022 14:08:11 +0200
+
 python3.10 (3.10.4-3) unstable; urgency=medium
 
   * Build a python3.10-nopie package, diverting the python3.10

debian/patches/gh-78214.diff

@@ -0,0 +1,24 @@
+``marshal.dumps()`` uses ``FLAG_REF`` for all interned strings.  This makes
+output more deterministic and helps reproducible build.
+
+diff --git a/Python/marshal.c b/Python/marshal.c
+index bbe67e3379fd9..90a4405091800 100644
+--- a/Python/marshal.c
++++ b/Python/marshal.c
+@@ -298,9 +298,14 @@ w_ref(PyObject *v, char *flag, WFILE *p)
+     if (p->version < 3 || p->hashtable == NULL)
+         return 0; /* not writing object references */
+ 
+-    /* if it has only one reference, it definitely isn't shared */
+-    if (Py_REFCNT(v) == 1)
++    /* If it has only one reference, it definitely isn't shared.
++     * But we use TYPE_REF always for interned string, to PYC file stable
++     * as possible.
++     */
++    if (Py_REFCNT(v) == 1 &&
++            !(PyUnicode_CheckExact(v) && PyUnicode_CHECK_INTERNED(v))) {
+         return 0;
++    }
+ 
+     entry = _Py_hashtable_get_entry(p->hashtable, v);
+     if (entry != NULL) {

debian/patches/series

@@ -39,3 +39,4 @@ destshared-location.diff
 fix-py_compile.diff
 reproducible-pyc.diff
 fix-ia64.diff
+gh-78214.diff