在 Objective-C++ 中使用 "new" 关键字 -> EXC_BAD_ACCESS 错误

Question

我在尝试使用 .mm 文件上的 .mm 关键字在运行时动态分配 c++ class 对象时遇到 EXC_BAD_ACCESS 错误设置为 objective-c++。对此的任何帮助或指导将不胜感激！当我在其原生 C++ 项目文件中运行这个游戏时，我遇到了零个问题。

#import "GameCode.h"
#include <cstdlib>
#include <chrono>
#include <cassert>
#include <fstream>
#include <iostream>
#import <GameKit/GameKit.h>
#import "GameKitHelper.h"
#import "CardView.h"
#import "MainFunctions.hpp"




@interface GameCode ()<GameKitHelperDelegate>
{
MainFunctions Main;
}
@property (weak, nonatomic) IBOutlet UIView *cardContainerView;

@end

@implementation GameCode

- (void)viewDidLoad
{
    // Do any additional setup after loading the view.
}

- (void)viewDidAppear:(BOOL)animated {

    [super viewDidLoad];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(playerAuthenticated)
                                                 name:LocalPlayerIsAuthenticated object:nil];
    [super viewDidAppear:animated];

Pack *pack = new Pack;// delete after game

//Pack *pack = Pack_Maker();
//Pack *pack = [Pack new];
//Pack *pack = [[Pack alloc] init];

默认 Pack 构造函数

Pack::Pack()
    : next(0)
{

 for (int i = 0; i < PACK_SIZE ; i++)
  {
    for(int j = 0; j < NUM_SUITS ; j++)
    {
        //K=7 TO k =0
        for(int k = 0; k < NUM_RANKS; k++)
        {
            cards[i] = Card(RANK_NAMES_BY_WEIGHT[k], SUIT_NAMES_BY_WEIGHT[j]);
            cards[i].get_value();
        i++;
        }
    }
  }
}

// Suits in order from lowest suit to highest suit.
constexpr const char* const SUIT_NAMES_BY_WEIGHT[] = {
  Card::SUIT_SPADES,
  Card::SUIT_HEARTS,
  Card::SUIT_CLUBS,
  Card::SUIT_DIAMONDS
};

使用卡片构造函数

Card::Card(const std::string &rank_in, const std::string &suit_in)
: rank(rank_in), suit(suit_in) {}

我什至尝试制作一个函数来为我动态分配它，但没有用。错误的访问错误似乎发生在默认的卡分配运算符 Card::operator= 中，所以我尝试创建一个自定义分配运算符，但问题仍然存在。

/*
Card & Card::operator=(const Card &that)
{
this->rank = that.get_rank();
this->suit = that.get_suit();
    return *this;
}
*/

下面是从 Card::operator= 到 char_traits<char>::assign:

中的致命错误的线程跟踪

`Card::operator=:
    0x1090682a0 <+0>:   pushq  %rbp
    0x1090682a1 <+1>:   movq   %rsp, %rbp
    0x1090682a4 <+4>:   subq   [=18=]x30, %rsp
    0x1090682a8 <+8>:   movq   %rdi, -0x8(%rbp)
    0x1090682ac <+12>:  movq   %rsi, -0x10(%rbp)
    0x1090682b0 <+16>:  movq   -0x8(%rbp), %rax
    0x1090682b4 <+20>:  movq   -0x10(%rbp), %rcx
    0x1090682b8 <+24>:  movl   (%rcx), %edx
    0x1090682ba <+26>:  movl   %edx, (%rax)
    0x1090682bc <+28>:  movq   %rax, %rcx
    0x1090682bf <+31>:  addq   [=18=]x8, %rcx
    0x1090682c6 <+38>:  movq   -0x10(%rbp), %rsi
    0x1090682ca <+42>:  addq   [=18=]x8, %rsi
    0x1090682d1 <+49>:  movq   %rcx, %rdi
    0x1090682d4 <+52>:  movq   %rax, -0x18(%rbp)
    0x1090682d8 <+56>:  callq  0x1090688f0               ; std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::operator= at string:2303
->  0x1090682dd <+61>:  movq   -0x18(%rbp), %rcx

`std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::operator=:
    0x1090688f0 <+0>:  pushq  %rbp
    0x1090688f1 <+1>:  movq   %rsp, %rbp
    0x1090688f4 <+4>:  subq   [=19=]x20, %rsp
    0x1090688f8 <+8>:  movq   %rdi, -0x8(%rbp)
    0x1090688fc <+12>: movq   %rsi, -0x10(%rbp)
    0x109068900 <+16>: movq   -0x8(%rbp), %rax
    0x109068904 <+20>: movq   -0x10(%rbp), %rsi
    0x109068908 <+24>: movq   %rax, %rdi
    0x10906890b <+27>: movq   %rax, -0x20(%rbp)
    0x10906890f <+31>: callq  0x109068920               ; std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::__move_assign at string:2291
->  0x109068914 <+36>: movq   -0x20(%rbp), %rax

`std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::__move_assign:
    0x109068920 <+0>:   pushq  %rbp
    0x109068921 <+1>:   movq   %rsp, %rbp
    0x109068924 <+4>:   subq   [=20=]x30, %rsp
    0x109068928 <+8>:   movq   %rdi, -0x10(%rbp)
    0x10906892c <+12>:  movq   %rsi, -0x18(%rbp)
    0x109068930 <+16>:  movq   -0x10(%rbp), %rax
    0x109068934 <+20>:  movq   %rax, %rdi
    0x109068937 <+23>:  movq   %rax, -0x20(%rbp)
    0x10906893b <+27>:  callq  0x109068990               ; std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::__clear_and_shrink at string:3819
->  0x109068940 <+32>:  movq   -0x18(%rbp), %rdi

`std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::__clear_and_shrink:
    0x109068990 <+0>:   pushq  %rbp
    0x109068991 <+1>:   movq   %rsp, %rbp
    0x109068994 <+4>:   subq   [=21=]x20, %rsp
    0x109068998 <+8>:   movq   %rdi, -0x8(%rbp)
    0x10906899c <+12>:  movq   -0x8(%rbp), %rax
    0x1090689a0 <+16>:  movq   %rax, %rdi
    0x1090689a3 <+19>:  movq   %rax, -0x10(%rbp)
    0x1090689a7 <+23>:  callq  0x109068ac0               ; std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::clear at string:3061
->  0x1090689ac <+28>:  movq   -0x10(%rbp), %rdi

`std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::clear:
    0x109068ac0 <+0>:   pushq  %rbp
    0x109068ac1 <+1>:   movq   %rsp, %rbp
    0x109068ac4 <+4>:   subq   [=22=]x20, %rsp
    0x109068ac8 <+8>:   movq   %rdi, -0x8(%rbp)
    0x109068acc <+12>:  movq   -0x8(%rbp), %rax
    0x109068ad0 <+16>:  movq   %rax, %rdi
    0x109068ad3 <+19>:  movq   %rax, -0x18(%rbp)
    0x109068ad7 <+23>:  callq  0x109068ce0               ; std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::__invalidate_all_iterators at string:1684
    0x109068adc <+28>:  jmp    0x109068ae1               ; <+33> at string
    0x109068ae1 <+33>:  movq   -0x18(%rbp), %rdi
    0x109068ae5 <+37>:  callq  0x109068b60               ; std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::__is_long at string:1420
    0x109068aea <+42>:  testb  [=22=]x1, %al
    0x109068aec <+44>:  jne    0x109068af7               ; <+55> at string
    0x109068af2 <+50>:  jmp    0x109068b22               ; <+98> at string
    0x109068af7 <+55>:  movq   -0x18(%rbp), %rdi
    0x109068afb <+59>:  callq  0x109068bf0               ; std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::__get_long_pointer at string:1499
    0x109068b00 <+64>:  movb   [=22=]x0, -0x9(%rbp)
    0x109068b04 <+68>:  movq   %rax, %rdi
    0x109068b07 <+71>:  leaq   -0x9(%rbp), %rsi
    0x109068b0b <+75>:  callq  0x109068cf0               ; std::__1::char_traits<char>::assign at __string:208
->  0x109068b10 <+80>:  xorl   %ecx, %ecx

`std::__1::char_traits<char>::assign:
    0x109068cf0 <+0>:  pushq  %rbp
    0x109068cf1 <+1>:  movq   %rsp, %rbp
    0x109068cf4 <+4>:  movq   %rdi, -0x8(%rbp)
    0x109068cf8 <+8>:  movq   %rsi, -0x10(%rbp)
    0x109068cfc <+12>: movq   -0x10(%rbp), %rax
    0x109068d00 <+16>: movb   (%rax), %cl
    0x109068d02 <+18>: movq   -0x8(%rbp), %rax
->  0x109068d06 <+22>: movb   %cl, (%rax)

Answer 1

您没有提供 cards 的声明和限制常量，但我觉得这个循环很可疑：

 for (int i = 0; i < PACK_SIZE ; i++)
  {
    for(int j = 0; j < NUM_SUITS ; j++)
    {
        //K=7 TO k =0
        for(int k = 0; k < NUM_RANKS; k++)
        {
            cards[i] = Card(RANK_NAMES_BY_WEIGHT[k], SUIT_NAMES_BY_WEIGHT[j]);
            cards[i].get_value();
        i++;
        }
    }
  }

我怀疑 i 超出了您的 cards 数组的范围。您在最外层循环的迭代表达式和最内层循环的主体中递增 i。

假设 NUM_SUITS 是 4 而 NUM_RANKS 是 13，就像在标准纸牌中一样，此代码将在第一次迭代时分配 cards[0] 到 cards[51]最外层循环，然后跳过 cards[52] 并将 cards[53] 分配给 cards[104]，跳过 cards[105]，依此类推。

我预计 cards 的维度可能是 NUM_SUITS * NUM_RANKS 的倍数，例如 156。在那个例子中，当内部循环试图分配给不存在 cards[156] 和 cards[157].

我建议也许将最外层循环更改为 while (i < PACK_SIZE) 并在您的代码中放置一些 assert 以确保数组维度和运行索引符合您的期望：

  int i = 0;
  while (i < PACK_SIZE)
  {
    assert(i + NUM_SUITS * NUM_RANKS <= cards.size());
    for(int j = 0; j < NUM_SUITS ; j++)
    {
        for(int k = 0; k < NUM_RANKS; k++)
        {
            cards[i] = Card(RANK_NAMES_BY_WEIGHT[k], SUIT_NAMES_BY_WEIGHT[j]);
            cards[i].get_value();
            i++;
        }
    }
  }
  assert(i <= cards.size());

不用说，如果这段代码是从纯 C++ 项目中逐字提取的，那么错误也存在。

在 Objective-C++ 中使用 "new" 关键字 -> EXC_BAD_ACCESS 错误

Using "new" keyword in Objective-C++ -> EXC_BAD_ACCESS Error

c++

ios

xcode

objective-c++