loop.c

extern int glob1, glob2;
 
extern int f (void) 
  /*@globals glob1@*/ 
  /*@modifies nothing@*/ ;
 
extern void g (void) 
  /*@modifies glob2@*/ ;
 
extern void h (void) ; 
 
void upto (int x) 
{
  while (x > f()) g();
  while (f() < 3) h();
}