bpo-39770, array module: Remove unnecessary descriptor counting (GH-18675)

Modules/arraymodule.c

@@ -2991,7 +2991,6 @@ array_modexec(PyObject *m)
 {
     char buffer[Py_ARRAY_LENGTH(descriptors)], *p;
     PyObject *typecodes;
-    Py_ssize_t size = 0;
     const struct arraydescr *descr;
 
     if (PyType_Ready(&Arraytype) < 0)
@@ -3009,10 +3008,6 @@ array_modexec(PyObject *m)
         return -1;
     }
 
-    for (descr=descriptors; descr->typecode != '\0'; descr++) {
-        size++;
-    }
-
     p = buffer;
     for (descr = descriptors; descr->typecode != '\0'; descr++) {
         *p++ = (char)descr->typecode;