Use of typeof

[Philip Cheng]

I would like to use typeof to determine the type of a variable.  
However, I keep getting the error when I try to compile the program.

  test.c: In function `main':
  test.c:8: parse error before "typeof"

Anyone knows how can I solve the problem?  Thanks in advance for your help.

Philip


Here is my test program:

#include <stdio.h>

main()
{
        double  dftest;
        dftest = 1.0;

        if (__builtin_types_compatible_p (typeof (dftest), double)) 
            printf("It is double\n");
}