Question

I’m getting a size discepancy while using long int in C. The following code:

#include <stdio.h>

void main()
{
    printf("%d\n", sizeof(long int));
}

gives 8 as output, so 64 bits are used to represent long int, right? But:

#include <stdio.h>

void main()
{
    long int a;
    a = 1;
    a = a << 32;
    printf("%d\n", a);
}

gives 0 (shifting by 31 gives -2147483648, which is -2**31). So, it seems that only 4 bytes are being used. What does this mean? I’m using gcc 4.4.5 with no flags

Answer 1

You’re printing it as a normal integer: printf("%d"). Try printing it as a long integer: printf("%ld ...").