Issue #9277: Struct module: standard bool packing was incorrect if

char is unsigned.  Thanks Stefan Krah for the patch.

Modules/_struct.c

@@ -867,11 +867,11 @@ bp_double(char *p, PyObject *v, const formatdef *f)
 static int
 bp_bool(char *p, PyObject *v, const formatdef *f)
 {
-    char y;
+    int y;
     y = PyObject_IsTrue(v);
     if (y < 0)
         return -1;
-    memcpy(p, (char *)&y, sizeof y);
+    *p = (char)y;
     return 0;
 }