printf. Число цифр после E/e.

#include <float.h>

int main()
{
    double foo;
    double mantis;
    int exponent;
    mantis = frexp( foo, &exponent);
    printf( "Foo is %8.2fE%s%4d", 
            mantis,
            (exp < 0) ? "-" : "+",
            exponent );
    
    return 0;
}

use of ‘ll’ length modifier with ‘e’ type character [-Werror=format]