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Date: Tue, 16 Aug 2011 17:27:19 +0100
From: "Richard W.M. Jones" <rich@annexia.org>
To: Dmitry Bely <dmitry.bely@gmail.com>
Cc: Caml List <caml-list@inria.fr>
Message-ID: <20110816162719.GD31932@annexia.org>
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User-Agent: Mutt/1.5.20 (2009-06-14)
Subject: Re: [Caml-list] Interfacing with C: bad practice

Grrr now _my_ program has a bug.

----------------------------------------------------------------------
#include <stdio.h>
#include <stdlib.h>

void f (int a, int b);
int g (void);
int *global = NULL;

int
main (void)
{
  int x = 1;
  global = &x;
  f (g (), x);

  exit (0);
}

void
f (int a, int b)
{
  printf ("a = %d, b = %d\n", a, b);
}

int
g (void)
{
  if (global) {
    (*global)++;
    return *global;
  }
  else
    return 42;
}
----------------------------------------------------------------------

This program doesn't show undefined behaviour.

Rich.

-- 
Richard Jones
Red Hat