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/**************************************************************************/
/* */
/* The Why platform for program certification */
/* Copyright (C) 2002-2008 */
/* Romain BARDOU */
/* Jean-Franois COUCHOT */
/* Mehdi DOGGUY */
/* Jean-Christophe FILLITRE */
/* Thierry HUBERT */
/* Claude MARCH */
/* Yannick MOY */
/* Christine PAULIN */
/* Yann RGIS-GIANAS */
/* Nicolas ROUSSET */
/* Xavier URBAIN */
/* */
/* This software is free software; you can redistribute it and/or */
/* modify it under the terms of the GNU General Public */
/* License version 2, as published by the Free Software Foundation. */
/* */
/* This software is distributed in the hope that it will be useful, */
/* but WITHOUT ANY WARRANTY; without even the implied warranty of */
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. */
/* */
/* See the GNU General Public License version 2 for more details */
/* (enclosed in the file GPL). */
/* */
/**************************************************************************/
class Trace {
/* Example 0
* We want the message:
* "assertion `x < 9' cannot be established"
* localized on `x < 9'
*/
/*@ ensures this.f == 0;
@*/
Trace() {
f = 0;
}
/* Example 1
* We want the message:
* "assertion `x < 9' cannot be established"
* localized on `x < 9'
*/
/*@ requires x > 0;
@*/
int m1(int x) {
//@ assert x >= 0 && x < 9;
return x+1;
}
/* Example 2
* We want the message:
* "post-condition `\result > 10' of function m2 cannot be established"
* localized on `return x+1'
* Bonus: all lines involved in the execution path should be ~underlined
*/
/*@ requires x > 0 && x < 100;
@ ensures \result != 0 && \result > 10;
@*/
int m2(int x) {
int y;
if (x<50)
return x+1;
else
y = x-1;
return y;
}
/* Example 3
* We want the message:
* "pre-condition `x > 0' for call to function m3 cannot be established"
* localized on `m2(x)'
*/
/*@ requires x >= 0 && x < 50;
@*/
int m3(int x) {
return m2(x);
}
/* Example 4
* Explanation expected:
* "validity of loop invariant `0 <= y' at loop entrance"
* localized on `while ...'
*/
void m4(int x) {
int y = x;
/*@ loop_invariant 0 <= y && y <= x;
@ decreases y;
@*/
while (y > 0)
{
y = y - 1;
}
}
/* Example 5
* Explanation expected:
* "preservation of loop invariant `y = x'"
* localized on the '}' closing the loop body
*/
void m5(int x) {
int y = x;
/*@ loop_invariant y == x;
@ decreases y;
@*/
while (y > 0) {
y = y - 1;
}
}
/* Example 6
* Explanation expected:
* "arithmetic overflow"
* localized on first "x", on "(byte)(x+1)" and on "(byte)(x+2)"
*/
byte m6(byte x) {
x += x+1;
x = (byte)(x+1);
return (byte)(x+2);
}
/* Example 7
* Explanation expected:
* "pointer dereferencing"
* localized on "p.f"
*/
int f;
int m7(Trace p)
{
return p.f;
}
/* Example 8
* Explanation expected:
* "pointer dereferencing"
* localized on "p.f"
*/
/*@ assigns p.f;
@ ensures p.f == 0;
@*/
void m8(Trace p)
{
p.f = 0;
}
}
/*
Local Variables:
mode: java
compile-command: "make Trace"
End:
*/
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