C 语言入门级问题，指针问题

[qw7692336]

#include <stdio.h>

void main(){
    int a = 5;
    int* b = &a;
    int* c = &b;
    printf("%d\n",&a==b);
    printf("%d\n",&b==c);
    printf("%d\n",a==*b);
    printf("%d\n",b==*c);
}

输出是
1
1
1
0

为何最后一个是0?

[wlee1991]

我就不信弄不粗来

` ` `
#include <stdio.h>

int main (int argc, const char * argv[]) {

int a = 5; //a is int
int * b = &a; //b is a pointer to int
int * * c = &b; //c is a pointer to int *
int * * * d = &c; //d is a pointer to int * *

printf ("a = %d, &a = %p\n", a, &a );
printf ("b = %p, &b = %p\n", b, &b );
printf ("c = %p, &c = %p\n", c, &c );
printf ("d = %p, &d = %p\n", d, &d );

printf ("*b = %d\n", *b );
printf ("**c = %d\n", **c );
printf ("***d = %d\n", ***d );

printf ("%d\n", &a == b );
printf ("%d\n", &b == c );
printf ("%d\n", &c == d );

printf ("%d\n", a == *b );
printf ("%d\n", b == *c );
printf ("%d\n", c == *d );

return 0;
}
` ` `

[testlc]

手动 markdown 好毅力 哈哈

[qw7692336]

@nozama
@weyou
改为
long* c = &b;
会输出 1 ；
果然是 64 位截断问题

[Banio]

In function 'main':
[Warning] initialization from incompatible pointer type [enabled by default]
[Warning] comparison of distinct pointer types lacks a cast [enabled by default]
[Warning] comparison between pointer and integer [enabled by default]

1
1
1
1
用的 dev cpp 5.1

[oska874]

32bit linux,64 bit cygwin,用 gcc 4.8+编译，都是编译有 warning ，但是结果都是 4 个 1 。

别用 vc 6 了，我们搞工控的都是 vs 2013 了。