add refcounting annotation that make test_long pass

from_cpython/Lib/test/test_long.py

-# expected: reffail
 import unittest
 import sys
 

src/runtime/classobj.cpp

@@ -1575,7 +1575,6 @@ Box* instanceInt(Box* _inst) {
     }
 
     Box* truncated = instanceTrunc(inst);
-    AUTO_DECREF(truncated);
     /* __trunc__ is specified to return an Integral type, but
        int() needs to return an int. */
     Box* res = _PyNumber_ConvertIntegralToInt(truncated, "__trunc__ returned non-Integral (type %.200s)");

src/runtime/long.cpp

@@ -712,11 +712,11 @@ template <ExceptionStyle S> Box* _longNew(Box* val, Box* _base) noexcept(S == CA
             Box* srepr = PyObject_Repr(val);
             if (S == CAPI) {
                 PyErr_Format(PyExc_ValueError, "invalid literal for long() with base %d: '%s'", base,
-                             PyString_AS_STRING(srepr));
+                             PyString_AS_STRING(autoDecref(srepr)));
                 return NULL;
             } else {
                 raiseExcHelper(ValueError, "invalid literal for long() with base %d: '%s'", base,
-                               PyString_AS_STRING(srepr));
+                               PyString_AS_STRING(autoDecref(srepr)));
             }
         }
         Box* r = PyLong_FromString(s->data(), NULL, base);