不含指针的结构体赋值实现，直接内存拷贝

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#include <stdio.h> #include <stdlib.h>   struct A {     int c;     char b[20];     char strs[10][10];     int k; };   int main() {     //  A a = {...}; // 帮我初始化     struct A a = {         1, // Initialize c with some integer         "Example String", // Initialize b with a string (fewer than 20 characters)         { // Initialize strs with strings (each fewer than 10 characters)             "String1", // First string             "String2", // Second string             "String3", // Third string             // You can initialize more or leave them empty which will default to zeros         },         42 // Initialize k with some integer     };     struct A b;     b = a;     printf("b.strs[0]=%s\n", b.strs[0]); }

　　

 

看下 b = a 的反汇编结果：

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struct A b;     b = a; 009C18E0  mov         ecx,20h  009C18E5  lea         esi,[a]  009C18EB  lea         edi,[b]  009C18F1  rep movs    dword ptr es:[edi],dword ptr [esi]      printf("b.strs[0]=%s\n", b.strs[0]);

　　

sizeof(A)  =  128 ==  20h*4（dword）