{"id":566,"date":"2016-10-11T13:14:25","date_gmt":"2016-10-11T13:14:25","guid":{"rendered":"http:\/\/lg.yusemo.com\/?p=566"},"modified":"2016-10-11T13:15:51","modified_gmt":"2016-10-11T13:15:51","slug":"566","status":"publish","type":"post","link":"https:\/\/lg.yusemo.com\/?p=566","title":{"rendered":"\u6df1\u5165\u7406\u89e3Java\u5185\u5b58\u6a21\u578b\uff08\u4e8c\uff09\u2014\u2014\u91cd\u6392\u5e8f"},"content":{"rendered":"

\u6570\u636e\u4f9d\u8d56\u6027<\/h2>\n

\u5982\u679c\u4e24\u4e2a\u64cd\u4f5c\u8bbf\u95ee\u540c\u4e00\u4e2a\u53d8\u91cf\uff0c\u4e14\u8fd9\u4e24\u4e2a\u64cd\u4f5c\u4e2d\u6709\u4e00\u4e2a\u4e3a\u5199\u64cd\u4f5c\uff0c\u6b64\u65f6\u8fd9\u4e24\u4e2a\u64cd\u4f5c\u4e4b\u95f4\u5c31\u5b58\u5728\u6570\u636e\u4f9d\u8d56\u6027\u3002\u6570\u636e\u4f9d\u8d56\u5206\u4e0b\u5217\u4e09\u79cd\u7c7b\u578b\uff1a<\/p>\n\n\n\n\n\n\n
\u540d\u79f0<\/td>\n\u4ee3\u7801\u793a\u4f8b<\/td>\n\u8bf4\u660e<\/td>\n<\/tr>\n
\u5199\u540e\u8bfb<\/td>\na = 1;b = a;<\/td>\n\u5199\u4e00\u4e2a\u53d8\u91cf\u4e4b\u540e\uff0c\u518d\u8bfb\u8fd9\u4e2a\u4f4d\u7f6e\u3002<\/td>\n<\/tr>\n
\u5199\u540e\u5199<\/td>\na = 1;a = 2;<\/td>\n\u5199\u4e00\u4e2a\u53d8\u91cf\u4e4b\u540e\uff0c\u518d\u5199\u8fd9\u4e2a\u53d8\u91cf\u3002<\/td>\n<\/tr>\n
\u8bfb\u540e\u5199<\/td>\na = b;b = 1;<\/td>\n\u8bfb\u4e00\u4e2a\u53d8\u91cf\u4e4b\u540e\uff0c\u518d\u5199\u8fd9\u4e2a\u53d8\u91cf\u3002<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u4e0a\u9762\u4e09\u79cd\u60c5\u51b5\uff0c\u53ea\u8981\u91cd\u6392\u5e8f\u4e24\u4e2a\u64cd\u4f5c\u7684\u6267\u884c\u987a\u5e8f\uff0c\u7a0b\u5e8f\u7684\u6267\u884c\u7ed3\u679c\u5c06\u4f1a\u88ab\u6539\u53d8\u3002<\/p>\n

\u524d\u9762\u63d0\u5230\u8fc7\uff0c\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u53ef\u80fd\u4f1a\u5bf9\u64cd\u4f5c\u505a\u91cd\u6392\u5e8f\u3002\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u5728\u91cd\u6392\u5e8f\u65f6\uff0c\u4f1a\u9075\u5b88\u6570\u636e\u4f9d\u8d56\u6027\uff0c\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u4e0d\u4f1a\u6539\u53d8\u5b58\u5728\u6570\u636e\u4f9d\u8d56\u5173\u7cfb\u7684\u4e24\u4e2a\u64cd\u4f5c\u7684\u6267\u884c\u987a\u5e8f\u3002<\/p>\n

\u6ce8\u610f\uff0c\u8fd9\u91cc\u6240\u8bf4\u7684\u6570\u636e\u4f9d\u8d56\u6027\u4ec5\u9488\u5bf9\u5355\u4e2a\u5904\u7406\u5668\u4e2d\u6267\u884c\u7684\u6307\u4ee4\u5e8f\u5217\u548c\u5355\u4e2a\u7ebf\u7a0b\u4e2d\u6267\u884c\u7684\u64cd\u4f5c\uff0c\u4e0d\u540c\u5904\u7406\u5668\u4e4b\u95f4\u548c\u4e0d\u540c\u7ebf\u7a0b\u4e4b\u95f4\u7684\u6570\u636e\u4f9d\u8d56\u6027\u4e0d\u88ab\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u8003\u8651\u3002<\/p>\n

as-if-serial\u8bed\u4e49<\/h2>\n

as-if-serial\u8bed\u4e49\u7684\u610f\u601d\u6307\uff1a\u4e0d\u7ba1\u600e\u4e48\u91cd\u6392\u5e8f\uff08\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u4e3a\u4e86\u63d0\u9ad8\u5e76\u884c\u5ea6\uff09\uff0c\uff08\u5355\u7ebf\u7a0b\uff09\u7a0b\u5e8f\u7684\u6267\u884c\u7ed3\u679c\u4e0d\u80fd\u88ab\u6539\u53d8\u3002\u7f16\u8bd1\u5668\uff0cruntime \u548c\u5904\u7406\u5668\u90fd\u5fc5\u987b\u9075\u5b88as-if-serial\u8bed\u4e49\u3002<\/p>\n

\u4e3a\u4e86\u9075\u5b88as-if-serial\u8bed\u4e49\uff0c\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u4e0d\u4f1a\u5bf9\u5b58\u5728\u6570\u636e\u4f9d\u8d56\u5173\u7cfb\u7684\u64cd\u4f5c\u505a\u91cd\u6392\u5e8f\uff0c\u56e0\u4e3a\u8fd9\u79cd\u91cd\u6392\u5e8f\u4f1a\u6539\u53d8\u6267\u884c\u7ed3\u679c\u3002\u4f46\u662f\uff0c\u5982\u679c\u64cd\u4f5c\u4e4b\u95f4\u4e0d\u5b58\u5728\u6570\u636e\u4f9d\u8d56\u5173\u7cfb\uff0c\u8fd9\u4e9b\u64cd\u4f5c\u53ef\u80fd\u88ab\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u91cd\u6392\u5e8f\u3002\u4e3a\u4e86\u5177\u4f53\u8bf4\u660e\uff0c\u8bf7\u770b\u4e0b\u9762\u8ba1\u7b97\u5706\u9762\u79ef\u7684\u4ee3\u7801\u793a\u4f8b\uff1a<\/p>\n

<\/div>\n
double pi  = 3.14;    \/\/A\ndouble r   = 1.0;     \/\/B\ndouble area = pi * r * r; \/\/C\n\n<\/pre>\n
\u4e0a\u9762\u4e09\u4e2a\u64cd\u4f5c\u7684\u6570\u636e\u4f9d\u8d56\u5173\u7cfb\u5982\u4e0b\u56fe\u6240\u793a\uff1a<\/p>\n
\"19079010-9124-4c38-9cd5-ffdf2fbe2f5f\"<\/p>\n
\u5982\u4e0a\u56fe\u6240\u793a\uff0cA\u548cC\u4e4b\u95f4\u5b58\u5728\u6570\u636e\u4f9d\u8d56\u5173\u7cfb\uff0c\u540c\u65f6B\u548cC\u4e4b\u95f4\u4e5f\u5b58\u5728\u6570\u636e\u4f9d\u8d56\u5173\u7cfb\u3002\u56e0\u6b64\u5728\u6700\u7ec8\u6267\u884c\u7684\u6307\u4ee4\u5e8f\u5217\u4e2d\uff0cC\u4e0d\u80fd\u88ab\u91cd\u6392\u5e8f\u5230A\u548cB\u7684\u524d\u9762\uff08C\u6392\u5230A\u548cB\u7684\u524d\u9762\uff0c\u7a0b\u5e8f\u7684\u7ed3\u679c\u5c06\u4f1a\u88ab\u6539\u53d8\uff09\u3002\u4f46A\u548cB\u4e4b\u95f4\u6ca1\u6709\u6570\u636e\u4f9d\u8d56\u5173\u7cfb\uff0c\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u53ef\u4ee5\u91cd\u6392\u5e8fA\u548cB\u4e4b\u95f4\u7684\u6267\u884c\u987a\u5e8f\u3002\u4e0b\u56fe\u662f\u8be5\u7a0b\u5e8f\u7684\u4e24\u79cd\u6267\u884c\u987a\u5e8f\uff1a\"a6bd02c4-5a3c-4847-94a0-923b730fd7cd\"<\/p>\n
as-if-serial\u8bed\u4e49\u628a\u5355\u7ebf\u7a0b\u7a0b\u5e8f\u4fdd\u62a4\u4e86\u8d77\u6765\uff0c\u9075\u5b88as-if-serial\u8bed\u4e49\u7684\u7f16\u8bd1\u5668\uff0cruntime \u548c\u5904\u7406\u5668\u5171\u540c\u4e3a\u7f16\u5199\u5355\u7ebf\u7a0b\u7a0b\u5e8f\u7684\u7a0b\u5e8f\u5458\u521b\u5efa\u4e86\u4e00\u4e2a\u5e7b\u89c9\uff1a\u5355\u7ebf\u7a0b\u7a0b\u5e8f\u662f\u6309\u7a0b\u5e8f\u7684\u987a\u5e8f\u6765\u6267\u884c\u7684\u3002as-if-serial\u8bed\u4e49\u4f7f\u5355\u7ebf\u7a0b\u7a0b\u5e8f\u5458\u65e0\u9700\u62c5\u5fc3\u91cd\u6392\u5e8f\u4f1a\u5e72\u6270\u4ed6\u4eec\uff0c\u4e5f\u65e0\u9700\u62c5\u5fc3\u5185\u5b58\u53ef\u89c1\u6027\u95ee\u9898\u3002<\/p>\n
\u7a0b\u5e8f\u987a\u5e8f\u89c4\u5219<\/h2>\n
\u6839\u636ehappens- before\u7684\u7a0b\u5e8f\u987a\u5e8f\u89c4\u5219\uff0c\u4e0a\u9762\u8ba1\u7b97\u5706\u7684\u9762\u79ef\u7684\u793a\u4f8b\u4ee3\u7801\u5b58\u5728\u4e09\u4e2ahappens- before\u5173\u7cfb\uff1a<\/p>\n
    \n
  1. A happens- before B\uff1b<\/li>\n
  2. B happens- before C\uff1b<\/li>\n
  3. A happens- before C\uff1b<\/li>\n<\/ol>\n
    \u8fd9\u91cc\u7684\u7b2c3\u4e2ahappens- before\u5173\u7cfb\uff0c\u662f\u6839\u636ehappens- before\u7684\u4f20\u9012\u6027\u63a8\u5bfc\u51fa\u6765\u7684\u3002<\/p>\n
    \u8fd9\u91ccA happens- before B\uff0c\u4f46\u5b9e\u9645\u6267\u884c\u65f6B\u5374\u53ef\u4ee5\u6392\u5728A\u4e4b\u524d\u6267\u884c\uff08\u770b\u4e0a\u9762\u7684\u91cd\u6392\u5e8f\u540e\u7684\u6267\u884c\u987a\u5e8f\uff09\u3002\u5728\u7b2c\u4e00\u7ae0\u63d0\u5230\u8fc7\uff0c\u5982\u679cA happens- before B\uff0cJMM\u5e76\u4e0d\u8981\u6c42A\u4e00\u5b9a\u8981\u5728B\u4e4b\u524d\u6267\u884c\u3002JMM\u4ec5\u4ec5\u8981\u6c42\u524d\u4e00\u4e2a\u64cd\u4f5c\uff08\u6267\u884c\u7684\u7ed3\u679c\uff09\u5bf9\u540e\u4e00\u4e2a\u64cd\u4f5c\u53ef\u89c1\uff0c\u4e14\u524d\u4e00\u4e2a\u64cd\u4f5c\u6309\u987a\u5e8f\u6392\u5728\u7b2c\u4e8c\u4e2a\u64cd\u4f5c\u4e4b\u524d\u3002\u8fd9\u91cc\u64cd\u4f5cA\u7684\u6267\u884c\u7ed3\u679c\u4e0d\u9700\u8981\u5bf9\u64cd\u4f5cB\u53ef\u89c1\uff1b\u800c\u4e14\u91cd\u6392\u5e8f\u64cd\u4f5cA\u548c\u64cd\u4f5cB\u540e\u7684\u6267\u884c\u7ed3\u679c\uff0c\u4e0e\u64cd\u4f5cA\u548c\u64cd\u4f5cB\u6309happens- before\u987a\u5e8f\u6267\u884c\u7684\u7ed3\u679c\u4e00\u81f4\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0cJMM\u4f1a\u8ba4\u4e3a\u8fd9\u79cd\u91cd\u6392\u5e8f\u5e76\u4e0d\u975e\u6cd5\uff08not illegal\uff09\uff0cJMM\u5141\u8bb8\u8fd9\u79cd\u91cd\u6392\u5e8f\u3002<\/p>\n
    \u5728\u8ba1\u7b97\u673a\u4e2d\uff0c\u8f6f\u4ef6\u6280\u672f\u548c\u786c\u4ef6\u6280\u672f\u6709\u4e00\u4e2a\u5171\u540c\u7684\u76ee\u6807\uff1a\u5728\u4e0d\u6539\u53d8\u7a0b\u5e8f\u6267\u884c\u7ed3\u679c\u7684\u524d\u63d0\u4e0b\uff0c\u5c3d\u53ef\u80fd\u7684\u5f00\u53d1\u5e76\u884c\u5ea6\u3002\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u9075\u4ece\u8fd9\u4e00\u76ee\u6807\uff0c\u4ecehappens- before\u7684\u5b9a\u4e49\u6211\u4eec\u53ef\u4ee5\u770b\u51fa\uff0cJMM\u540c\u6837\u9075\u4ece\u8fd9\u4e00\u76ee\u6807\u3002<\/p>\n
    \u91cd\u6392\u5e8f\u5bf9\u591a\u7ebf\u7a0b\u7684\u5f71\u54cd<\/h2>\n
    \u73b0\u5728\u8ba9\u6211\u4eec\u6765\u770b\u770b\uff0c\u91cd\u6392\u5e8f\u662f\u5426\u4f1a\u6539\u53d8\u591a\u7ebf\u7a0b\u7a0b\u5e8f\u7684\u6267\u884c\u7ed3\u679c\u3002\u8bf7\u770b\u4e0b\u9762\u7684\u793a\u4f8b\u4ee3\u7801\uff1a<\/p>\n
    class ReorderExample {\nint a = 0;\nboolean flag = false;\n\npublic void writer() {\n    a = 1;                   \/\/1\n    flag = true;             \/\/2\n}\n\nPublic void reader() {\n    if (flag) {                \/\/3\n        int i =  a * a;        \/\/4\n        \u2026\u2026\n    }\n}\n}\n\n<\/pre>\n
    flag\u53d8\u91cf\u662f\u4e2a\u6807\u8bb0\uff0c\u7528\u6765\u6807\u8bc6\u53d8\u91cfa\u662f\u5426\u5df2\u88ab\u5199\u5165\u3002\u8fd9\u91cc\u5047\u8bbe\u6709\u4e24\u4e2a\u7ebf\u7a0bA\u548cB\uff0cA\u9996\u5148\u6267\u884cwriter()\u65b9\u6cd5\uff0c\u968f\u540eB\u7ebf\u7a0b\u63a5\u7740\u6267\u884creader()\u65b9\u6cd5\u3002\u7ebf\u7a0bB\u5728\u6267\u884c\u64cd\u4f5c4\u65f6\uff0c\u80fd\u5426\u770b\u5230\u7ebf\u7a0bA\u5728\u64cd\u4f5c1\u5bf9\u5171\u4eab\u53d8\u91cfa\u7684\u5199\u5165\uff1f<\/p>\n
    \u7b54\u6848\u662f\uff1a\u4e0d\u4e00\u5b9a\u80fd\u770b\u5230\u3002<\/p>\n
    \u7531\u4e8e\u64cd\u4f5c1\u548c\u64cd\u4f5c2\u6ca1\u6709\u6570\u636e\u4f9d\u8d56\u5173\u7cfb\uff0c\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u53ef\u4ee5\u5bf9\u8fd9\u4e24\u4e2a\u64cd\u4f5c\u91cd\u6392\u5e8f\uff1b\u540c\u6837\uff0c\u64cd\u4f5c3\u548c\u64cd\u4f5c4\u6ca1\u6709\u6570\u636e\u4f9d\u8d56\u5173\u7cfb\uff0c\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u4e5f\u53ef\u4ee5\u5bf9\u8fd9\u4e24\u4e2a\u64cd\u4f5c\u91cd\u6392\u5e8f\u3002\u8ba9\u6211\u4eec\u5148\u6765\u770b\u770b\uff0c\u5f53\u64cd\u4f5c1\u548c\u64cd\u4f5c2\u91cd\u6392\u5e8f\u65f6\uff0c\u53ef\u80fd\u4f1a\u4ea7\u751f\u4ec0\u4e48\u6548\u679c\uff1f\u8bf7\u770b\u4e0b\u9762\u7684\u7a0b\u5e8f\u6267\u884c\u65f6\u5e8f\u56fe\uff1a<\/p>\n
    \"f0c71f3d-d343-4433-96b5-7a588859c08c\"<\/p>\n
    \u5982\u4e0a\u56fe\u6240\u793a\uff0c\u64cd\u4f5c1\u548c\u64cd\u4f5c2\u505a\u4e86\u91cd\u6392\u5e8f\u3002\u7a0b\u5e8f\u6267\u884c\u65f6\uff0c\u7ebf\u7a0bA\u9996\u5148\u5199\u6807\u8bb0\u53d8\u91cfflag\uff0c\u968f\u540e\u7ebf\u7a0bB\u8bfb\u8fd9\u4e2a\u53d8\u91cf\u3002\u7531\u4e8e\u6761\u4ef6\u5224\u65ad\u4e3a\u771f\uff0c\u7ebf\u7a0bB\u5c06\u8bfb\u53d6\u53d8\u91cfa\u3002\u6b64\u65f6\uff0c\u53d8\u91cfa\u8fd8\u6839\u672c\u6ca1\u6709\u88ab\u7ebf\u7a0bA\u5199\u5165\uff0c\u5728\u8fd9\u91cc\u591a\u7ebf\u7a0b\u7a0b\u5e8f\u7684\u8bed\u4e49\u88ab\u91cd\u6392\u5e8f\u7834\u574f\u4e86\uff01<\/p>\n
    \u203b\u6ce8\uff1a\u672c\u6587\u7edf\u4e00\u7528\u7ea2\u8272\u7684\u865a\u7bad\u7ebf\u8868\u793a\u9519\u8bef\u7684\u8bfb\u64cd\u4f5c\uff0c\u7528\u7eff\u8272\u7684\u865a\u7bad\u7ebf\u8868\u793a\u6b63\u786e\u7684\u8bfb\u64cd\u4f5c\u3002<\/p>\n
    \u4e0b\u9762\u518d\u8ba9\u6211\u4eec\u770b\u770b\uff0c\u5f53\u64cd\u4f5c3\u548c\u64cd\u4f5c4\u91cd\u6392\u5e8f\u65f6\u4f1a\u4ea7\u751f\u4ec0\u4e48\u6548\u679c\uff08\u501f\u52a9\u8fd9\u4e2a\u91cd\u6392\u5e8f\uff0c\u53ef\u4ee5\u987a\u4fbf\u8bf4\u660e\u63a7\u5236\u4f9d\u8d56\u6027\uff09\u3002\u4e0b\u9762\u662f\u64cd\u4f5c3\u548c\u64cd\u4f5c4\u91cd\u6392\u5e8f\u540e\uff0c\u7a0b\u5e8f\u7684\u6267\u884c\u65f6\u5e8f\u56fe\uff1a<\/p>\n
    \"597b35ec-a36b-4eb9-9e73-e7041f5c0579\"<\/p>\n
    \u5728\u7a0b\u5e8f\u4e2d\uff0c\u64cd\u4f5c3\u548c\u64cd\u4f5c4\u5b58\u5728\u63a7\u5236\u4f9d\u8d56\u5173\u7cfb\u3002\u5f53\u4ee3\u7801\u4e2d\u5b58\u5728\u63a7\u5236\u4f9d\u8d56\u6027\u65f6\uff0c\u4f1a\u5f71\u54cd\u6307\u4ee4\u5e8f\u5217\u6267\u884c\u7684\u5e76\u884c\u5ea6\u3002\u4e3a\u6b64\uff0c\u7f16\u8bd1\u5668\u548c\u5904\u7406\u5668\u4f1a\u91c7\u7528\u731c\u6d4b\uff08Speculation\uff09\u6267\u884c\u6765\u514b\u670d\u63a7\u5236\u76f8\u5173\u6027\u5bf9\u5e76\u884c\u5ea6\u7684\u5f71\u54cd\u3002\u4ee5\u5904\u7406\u5668\u7684\u731c\u6d4b\u6267\u884c\u4e3a\u4f8b\uff0c\u6267\u884c\u7ebf\u7a0bB\u7684\u5904\u7406\u5668\u53ef\u4ee5\u63d0\u524d\u8bfb\u53d6\u5e76\u8ba1\u7b97a*a\uff0c\u7136\u540e\u628a\u8ba1\u7b97\u7ed3\u679c\u4e34\u65f6\u4fdd\u5b58\u5230\u4e00\u4e2a\u540d\u4e3a\u91cd\u6392\u5e8f\u7f13\u51b2\uff08reorder buffer ROB\uff09\u7684\u786c\u4ef6\u7f13\u5b58\u4e2d\u3002\u5f53\u63a5\u4e0b\u6765\u64cd\u4f5c3\u7684\u6761\u4ef6\u5224\u65ad\u4e3a\u771f\u65f6\uff0c\u5c31\u628a\u8be5\u8ba1\u7b97\u7ed3\u679c\u5199\u5165\u53d8\u91cfi\u4e2d\u3002<\/p>\n
    \u4ece\u56fe\u4e2d\u6211\u4eec\u53ef\u4ee5\u770b\u51fa\uff0c\u731c\u6d4b\u6267\u884c\u5b9e\u8d28\u4e0a\u5bf9\u64cd\u4f5c3\u548c4\u505a\u4e86\u91cd\u6392\u5e8f\u3002\u91cd\u6392\u5e8f\u5728\u8fd9\u91cc\u7834\u574f\u4e86\u591a\u7ebf\u7a0b\u7a0b\u5e8f\u7684\u8bed\u4e49\uff01<\/p>\n
    \u5728\u5355\u7ebf\u7a0b\u7a0b\u5e8f\u4e2d\uff0c\u5bf9\u5b58\u5728\u63a7\u5236\u4f9d\u8d56\u7684\u64cd\u4f5c\u91cd\u6392\u5e8f\uff0c\u4e0d\u4f1a\u6539\u53d8\u6267\u884c\u7ed3\u679c\uff08\u8fd9\u4e5f\u662fas-if-serial\u8bed\u4e49\u5141\u8bb8\u5bf9\u5b58\u5728\u63a7\u5236\u4f9d\u8d56\u7684\u64cd\u4f5c\u505a\u91cd\u6392\u5e8f\u7684\u539f\u56e0\uff09\uff1b\u4f46\u5728\u591a\u7ebf\u7a0b\u7a0b\u5e8f\u4e2d\uff0c\u5bf9\u5b58\u5728\u63a7\u5236\u4f9d\u8d56\u7684\u64cd\u4f5c\u91cd\u6392\u5e8f\uff0c\u53ef\u80fd\u4f1a\u6539\u53d8\u7a0b\u5e8f\u7684\u6267\u884c\u7ed3\u679c<\/p>\n","protected":false},"excerpt":{"rendered":"
    \u6570\u636e\u4f9d\u8d56\u6027 \u5982\u679c\u4e24\u4e2a\u64cd\u4f5c\u8bbf\u95ee\u540c\u4e00\u4e2a\u53d8\u91cf\uff0c\u4e14\u8fd9\u4e24\u4e2a\u64cd\u4f5c\u4e2d\u6709\u4e00\u4e2a\u4e3a\u5199\u64cd\u4f5c\uff0c\u6b64\u65f6\u8fd9\u4e24\u4e2a\u64cd\u4f5c\u4e4b\u95f4\u5c31\u5b58\u5728\u6570\u636e\u4f9d\u8d56\u6027\u3002\u6570\u636e\u4f9d\u8d56\u5206\u4e0b\u5217\u4e09\u79cd\u7c7b\u578b\uff1a \u540d\u79f0 \u4ee3\u7801\u793a\u4f8b \u8bf4\u660e \u5199\u540e\u8bfb a = 1;b = a; \u5199\u4e00\u4e2a\u53d8\u91cf\u4e4b\u540e\uff0c\u518d\u8bfb\u8fd9\u4e2a\u4f4d\u7f6e\u3002 \u5199\u540e\u5199 a = 1;a = 2; \u5199\u4e00\u4e2a\u53d8\u91cf\u4e4b\u540e\uff0c\u518d\u5199\u8fd9\u4e2a\u53d8\u91cf\u3002 \u8bfb\u540e\u5199 a =…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[22],"tags":[3,30,22],"_links":{"self":[{"href":"https:\/\/lg.yusemo.com\/index.php?rest_route=\/wp\/v2\/posts\/566"}],"collection":[{"href":"https:\/\/lg.yusemo.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lg.yusemo.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lg.yusemo.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/lg.yusemo.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=566"}],"version-history":[{"count":3,"href":"https:\/\/lg.yusemo.com\/index.php?rest_route=\/wp\/v2\/posts\/566\/revisions"}],"predecessor-version":[{"id":573,"href":"https:\/\/lg.yusemo.com\/index.php?rest_route=\/wp\/v2\/posts\/566\/revisions\/573"}],"wp:attachment":[{"href":"https:\/\/lg.yusemo.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=566"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lg.yusemo.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=566"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lg.yusemo.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=566"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}