Strange (long double) results from simple program

From a simple program in the online C-book (example 2.2), I get the
strangest results. The long double type, generates huge numbers, but
no error messages anywhere (not during compile, not runtime).
This is the program
main(){
float f_var; double d_var; long double l_d_var;
int i;
i = 0;

 

The question is not clear

 

long double and double are same. both of them are supported in C as well as both of them are 64 bit variable.