Use isImmortalPythonObject

Author: fangerer

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/cext/capi/transitions/CApiTransitions.java

@@ -1866,7 +1866,7 @@ static long doPythonObject(Node inliningTarget, PythonObject pythonObject, boole
             if (!pythonObject.isNative()) {
                 assert !CApiContext.isSpecialSingleton(pythonObject);
                 PythonContext context = PythonContext.get(inliningTarget);
-                boolean immortal = isImmortal(context, pythonObject);
+                boolean immortal = isImmortalPythonObject(context, pythonObject);
                 pointer = firstToNativeNode.execute(inliningTarget, pythonObject, FirstToNativeNode.getInitialRefcnt(needsTransfer, immortal));
                 pythonObject.setNativePointer(pointer);
             } else {
@@ -1992,6 +1992,7 @@ public static boolean isImmortal(PythonContext context, Object object) {
          * immortal.
          */
         private static boolean isImmortalPythonObject(PythonContext context, PythonObject pythonObject) {
+            assert !CApiContext.isSpecialSingleton(pythonObject);
             return pythonObject instanceof PythonBuiltinClass || context.getTrue() == pythonObject || context.getFalse() == pythonObject || pythonObject instanceof PMemoryView;
         }