将 char[][] 转换为 char** 会导致段错误吗？

好吧，我的 C 有点生疏了，但我想我应该用 C 来做我的下一个（小）项目，这样我就可以对其进行抛光，并且我已经有不到 20 行的段错误了。

这是我的完整代码：

#define ROWS 4
#define COLS 4

char main_map[ROWS][COLS+1]={
  "a.bb",
  "a.c.",
  "adc.",
  ".dc."};

 void print_map(char** map){
  int i;
  for(i=0;i<ROWS;i++){
    puts(map[i]); //segfault here
  }
 }



int main(){
  print_map(main_map); //if I comment out this line it will work.
  puts(main_map[3]);
  return 0;
}

我完全不明白这是如何导致段错误的。投射时发生了什么[][] to **！？这是我收到的唯一警告。

rushhour.c:23:3: warning: passing argument 1 of ‘print_map’ from incompatible pointer type
rushhour.c:13:7: note: expected ‘char **’ but argument is of type ‘char (*)[5]’
  

Are [][] and **真的不兼容指针类型吗？对我来说它们似乎只是语法。

A char[ROWS][COLS+1]不能被投射到char**。输入参数print_map应该

void print_map(char map[][COLS+1])

or

void print_map(char (*map)[COLS+1])

区别在于char**意味着指向可以取消引用的东西，如下所示：

   (char**)map
       |
       v
  +--------+--------+------+--------+-- ...
  | 0x1200 | 0x1238 | NULL | 0x1200 |
  +----|---+----|---+--|---+----|---+-- ...
       v        |      =        |
    +-------+   |               |
    | "foo" | <-----------------'
    +-------+   |
                v
             +---------------+
             | "hello world" |
             +---------------+

While a char(*)[n]a 指向这样的连续内存区域

   (char(*)[5])map
       |
       v
  +-----------+---------+---------+-------------+-- ...
  | "foo\0\0" | "hello" | " worl" | "d\0\0\0\0" |
  +-----------+---------+---------+-------------+-- ...

如果您治疗一个(char(*)[5]) as a (char**)你得到垃圾：

   (char**)map
       |
       v
  +-----------+---------+---------+-------------+-- ...
  | "foo\0\0" | "hello" | " worl" | "d\0\0\0\0" |
  +-----------+---------+---------+-------------+-- ...
      force cast (char[5]) into (char*):
  +----------+------------+------------+------------+-- ...
  | 0x6f6f66 | 0x6c686500 | 0x77206f6c | 0x646c726f |
  +----|-----+---------|--+------|-----+------|-----+-- ...
       v               |         |            |
    +---------------+  |         |            v
    | "hsd®yœâñ~22" |  |         |       launch a missile
    +---------------+  |         |
                       v         v
               none of your process memory
                        SEGFAULT