C语言——数据类型 【32位/64位】下的字节大小

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#include 
#include 
typedef unsigned char byte;

int main(int argc,char *agv[])
{

        printf("1.char = %ldn",sizeof(char));
        printf("2.short = %ldn",sizeof(short));
        printf("3.int = %ldn",sizeof(int));
        printf("4.long = %ldn",sizeof(long));
        printf("5.float = %ldn",sizeof(float));
        printf("6.double = %ldn",sizeof(double));
        printf("7.bool = %ldn",sizeof(bool));
        printf("8.byte = %ldn",sizeof(byte));
        return 0;
}

  gcc datatype.c -g -O0 -o datatype-m64
  ./datatype

1.char = 1
2.short = 2
3.int = 4
4.long = 8
5.float = 4
6.double = 8
7.bool = 1
8.byte = 1

#include 
#include 
typedef unsigned char byte;

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

        printf("1.char = %dn",sizeof(char));
        printf("2.short = %dn",sizeof(short));
        printf("3.int = %dn",sizeof(int));
        printf("4.long = %dn",sizeof(long));
        printf("5.float = %dn",sizeof(float));
        printf("6.double = %dn",sizeof(double));
        printf("7.bool = %dn",sizeof(bool));
        printf("8.byte = %dn",sizeof(byte));
        return 0;
}

  gcc datatype.c -g -O0 -o datatype-m64
  ./datatype

1.char = 1
2.short = 2
3.int = 4
4.long = 4
5.float = 4
6.double = 8
7.bool = 1
8.byte = 1

#include 
int main(int argc,char *argv[])
{
        typedef union
        {
                int a;
                long b; 
                char c; 
                int d[5];
        }UNIOn;
        int e[5];
        typedef struct
        {
                short i;
                int j;
                double k;
        }STRUCT;

        printf("%dn",sizeof(e));
        printf("%dn",sizeof(UNIOn));
        printf("%dn",sizeof(STRUCT));
        return 0;
}

64位：
  gcc datatype.c -g -O0 -o datatype-m64
  ./datatype

20
24
16

32位：
  gcc datatype.c -g -O0 -o datatype-m32
  ./datatype

20
20
16

#include 
#include 


void test_1(char str_1[100])
{
        printf("str_1:%ldn",sizeof(str_1));
}

void test_2()
{
        void *p = malloc(100);
        printf("p:%ldn",sizeof(p));

}

void test_3()
{
        char str_2[10];
        printf("str_2:%ldn",sizeof(str_2));
}

int main(int argc,char *argv[])
{
        char str[100];
        test_1(str);
        test_2();
        test_3();
        return 0;
}
#输出：（64位系统下）
str_1:8
p:8
str_2:10