🚀 go-pugleaf

If I compile it with another C-compiler, it works.
It works also, if I call f in Int directly. Nobody could tell me, why.
So, if anyone had a Idea what is wrong with it, I would be very glad.
I work with a hp 700, gcc version 2.3.2 .
I compiled it with     gcc Int.c -lm .


Here's the program :

/* kleines C-Programm fuer Stephan, der C lernt */

#include <stdio.h>
#include <math.h>  /* falls exp, sin, ... erwuenscht */

double f(double x)
{ return x*x;      /* zum einfachen Testen */
}

double Int(double (*f)(double),double a, double b, int n)
{ double h, w, s = 0.0;
  int i;
  h = (b-a)/n;
  printf("h: %f\n",h);
  for(i=0;i<n;i++)
     { w = (*f)(a+i*h);
       s += w*h;
       printf("Schritt %d, w: %f, s: %f\n",i,w,s);
     };
  return s;
}

int main(void)
{ double a,b,Erg;
  int n;
  printf("Bitte a eingeben: ");
  scanf("%lf",&a);
  printf("Bitte b eingeben: ");
  scanf("%lf",&b);
  printf("Bitte die Anzahl der Schritte eingeben: ");
  scanf("%d",&n);
  printf("f(0): %f\n",f(0.0));
  Erg = Int(&f,a,b,n);
  printf("Ergebnis ist : Int(%f,%f) = %f\n",a,b,Erg);
  return 0;
}