{"id":577,"date":"2016-07-11T22:20:58","date_gmt":"2016-07-11T14:20:58","guid":{"rendered":"http:\/\/blog.sorayuki.net\/?p=577"},"modified":"2017-01-21T02:17:52","modified_gmt":"2017-01-20T18:17:52","slug":"c%e4%b8%ad%e5%a4%9a%e9%87%8d%e7%bb%a7%e6%89%bf%e7%9a%84%e6%8c%87%e9%92%88%e8%bd%ac%e6%8d%a2","status":"publish","type":"post","link":"https:\/\/blog.sorayuki.net\/?p=577","title":{"rendered":"VC++\u4e2d\u591a\u91cd\u7ee7\u627f\u7684\u6307\u9488\u8f6c\u6362"},"content":{"rendered":"

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<\/p>\n

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struct B1 { int a; };\r\nstruct B2 { int b; };\r\nstruct X : public B1, public B2 { int c; };\r\n\r\nint main()\r\n{\r\n    X* x = new X();\r\n    B2* b2 = x;\r\n    delete b2;\r\n}<\/pre>\n
\u8f6c\u5230\u53cd\u6c47\u7f16\u4e4b\u540e\uff0c\u53ef\u4ee5\u770b\u5230\u5b83\u5c31\u662f\u628ab2\u7684\u5730\u5740\u9001\u5230delete\u91cc\u9762\u53bb\u8c03\u7528\uff0c\u679c\u7136\u5d29\u6389\u4e86\u3002<\/p>\n
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struct B1 { virtual ~B1(){} int a; };\r\nstruct B2 { virtual ~B2(){} int b; };\r\nstruct X : public B1, public B2 { int c; };\r\n\r\nint main()\r\n{\r\n    X* x = new X();\r\n    B2* b2 = x;\r\n    delete b2;\r\n}<\/pre>\n
\u52a0\u4e86\u865a\u62df\u6790\u6784\u51fd\u6570\u4e4b\u540e\uff0c\u7a0b\u5e8f\u679c\u7136\u8fd0\u884c\u8d77\u6765\u5c31\u4e0d\u5d29\u4e86\u3002\u67e5\u770b\u53cd\u6c47\u7f16\uff0c\u4f1a\u53d1\u73b0\u5728delete b2\u7684\u65f6\u5019\uff0c\u5b83\u76f4\u63a5\u8c03\u7528\u865a\u51fd\u6570\u8868\u91cc\u7684B2\u6790\u6784\u51fd\u6570\u7684\u6307\u9488\uff08\u5728X\u5bf9\u8c61\u91cc\uff0cB2\u865a\u8868\u91cc\u7684\u6790\u6784\u51fd\u6570\u662fX\u5bf9\u8c61\u7684\uff09\uff0c\u800c\u8fd9\u4e2a\u51fd\u6570\u91cc\u9762\u7684\u5185\u5bb9\u662f\u628a\u6307\u9488\u4eceB2\u504f\u79fb\u56de\u6765\uff0c\u53d8\u6210X*\u7c7b\u578b\uff0c\u7136\u540e\u6267\u884cX\u7684\u6790\u6784\u51fd\u6570\uff0c\u6790\u6784\u51fd\u6570\u7684\u6700\u540e\u81ea\u5e26delete\u7684\u8c03\u7528\uff0c\u4e8e\u662f\u8fd9\u6837\u91ca\u653e\u8d77\u6765\u5c31\u6ca1\u6709\u95ee\u9898\u4e86\u3002<\/p>\n
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#include <stdio.h>\r\n\r\nstruct B1 {\r\n    virtual ~B1(){}\r\n    int a;\r\n};\r\n\r\nstruct B2 {\r\n    virtual ~B2(){} \r\n    virtual void F() { printf(\"%p\\n\", this); }\r\n    int b; \r\n};\r\n\r\nstruct X : public B1, public B2 {\r\n    void F() override { printf(\"%p\\n\", this); }\r\n    int c; \r\n};\r\n\r\nint main()\r\n{\r\n    X* x = new X();\r\n    B2* b2 = x;\r\n    x->F();\r\n    b2->F();\r\n    delete b2;\r\n}<\/pre>\n
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