/* * Copyright (C) 2014 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ class A { public: virtual int getRandomNumber() { return 4; // chosen by fair dice roll. // guaranteed to be random. } virtual ~A() {} }; A a; // nested macros to make it easy to define a large amount of read-only data // which will require relocation. #define A_16 &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, #define A_128 A_16 A_16 A_16 A_16 A_16 A_16 A_16 A_16 #define A_1024 A_128 A_128 A_128 A_128 A_128 A_128 A_128 A_128 extern "C" A* const lots_of_relro[] = { A_1024 A_1024 A_1024 A_1024 A_1024 A_1024 A_1024 A_1024 }; extern "C" int getRandomNumber() { // access the relro section (twice, in fact, once for the pointer, and once // for the vtable of A) to check it's actually there. return lots_of_relro[0]->getRandomNumber(); }