Question

尝试初始化此typedef结构时，我做错了什么。

我在linux中做了同样的声明，我可以创造完美。

这是定义：

typedef struct {                                                               
 char mask;    /* char data will be bitwise AND with this */                   
 char lead;    /* start bytes of current char in utf-8 encoded character */    
 uint32_t beg; /* beginning of codepoint range */                              
 uint32_t end; /* end of codepoint range */                                    
 int bits_stored; /* the number of bits from the codepoint that fits in char */
}utf_t;                                                                        
utf_t * utf[];                                                                 
/*                 mask        lead        beg      end       bits  */         
 utf_t * utf[] = {                                                           
    [0] = &(utf_t){0b00111111, 0b10000000, 0,       0,        6    },          
    [1] = &(utf_t){0b01111111, 0b00000000, 0000,    0177,     7    },          
    [2] = &(utf_t){0b00011111, 0b11000000, 0200,    03777,    5    },          
    [3] = &(utf_t){0b00001111, 0b11100000, 04000,   0177777,  4    },          
    [4] = &(utf_t){0b00000111, 0b11110000, 0200000, 04177777, 3    },          
          &(utf_t){0},                                                         
   };

当我尝试编译时，我不创建假脱机文件，但是在作业日志中显示以下消息：

Message ID . . . . . . :   MCH3601       Severity . . . . . . . :   40       
Message type . . . . . :   Escape                                            
Date sent  . . . . . . :   18/11/19      Time sent  . . . . . . :   10:02:49 

Message . . . . :   Pointer not set for location referenced.                 
Cause . . . . . :   A pointer was used, either directly or as a basing       
  pointer, that has not been set to an address.

有人可以告诉我我做错了什么吗？谢谢。

关于

Answer 1

根据文档here，IBM i C / C ++编译器不识别二进制整数文字。实际上，如果我尝试编译您的代码段，则二进制文字上的代码段将失败。但是，如果我将二进制文字转换为十六进制文字，它将起作用：

#include <stdint.h>

typedef struct {
 char mask;    /* char data will be bitwise AND with this */
 char lead;    /* start bytes of current char in utf-8 encoded character */
 uint32_t beg; /* beginning of codepoint range */
 uint32_t end; /* end of codepoint range */
 int bits_stored; /* the number of bits from the codepoint that fits in char */
}utf_t;
utf_t * utf[];
/*                 mask  lead  beg      end       bits  */
 utf_t * utf[] = {
    [0] = &(utf_t){0x3f, 0x80, 0,       0,        6    },
    [1] = &(utf_t){0x7f, 0x00, 0000,    0177,     7    },
    [2] = &(utf_t){0x1f, 0xc0, 0200,    03777,    5    },
    [3] = &(utf_t){0x0f, 0xe0, 04000,   0177777,  4    },
    [4] = &(utf_t){0x07, 0xf0, 0200000, 04177777, 3    },
          &(utf_t){0},
   };

Answer 2

您在此处使用复合文字：

两种初始化方式：

utf_t *utf[6];  
utf_t *utf1[] = {                                                           
    &(utf_t){0b00111111, 0b10000000, 0,       0,        6    },          
    &(utf_t){0b01111111, 0b00000000, 0000,    0177,     7    },          
    &(utf_t){0b00011111, 0b11000000, 0200,    03777,    5    },          
    &(utf_t){0b00001111, 0b11100000, 04000,   0177777,  4    },          
    &(utf_t){0b00000111, 0b11110000, 0200000, 04177777, 3    },          
    &(utf_t){0},                                                         
   };                                                               

void foo(void)
{

memcpy(utf, (utf_t *[]){                                                           
    &(utf_t){0b00111111, 0b10000000, 0,       0,        6    },          
    &(utf_t){0b01111111, 0b00000000, 0000,    0177,     7    },          
    &(utf_t){0b00011111, 0b11000000, 0200,    03777,    5    },          
    &(utf_t){0b00001111, 0b11100000, 04000,   0177777,  4    },          
    &(utf_t){0b00000111, 0b11110000, 0200000, 04177777, 3    },          
    &(utf_t){0},                                                         
   }, sizeof(utf));
}

int main()
{
    int arr[1000];
    foo();
    memset(arr,0, sizeof(arr));
    printf("%hhu %hhu %u\n", utf[2] -> mask, utf[2] -> lead, utf[2] -> beg);
    printf("%hhu %hhu %u", utf1[2] -> mask, utf1[2] -> lead, utf1[2] -> beg);
}

https://godbolt.org/z/CegYGb

在C（Iseries / AS400）中初始化typedef结构时出现问题

2 个答案: