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typedef struct
{
/*@only@*/ char *name;
int val;
} *stx;
/*@only@*/ char *stx_name (stx x)
{
return (x->name); /* 1. Function returns reference to parameter x: (x->name)
** [2]. Return value exposes rep of stx: (x->name)
** 3. Released storage x->name reachable from parameter
*/
}
/*@observer@*/ char *stx_observeName (stx x)
{
return (x->name);
}
/*@exposed@*/ char *stx_exposeName (stx x)
{
return (x->name); /* okay */
}
char *f (stx x)
{
char *s;
s = stx_name (x);
free (s); /* okay */
s = stx_observeName (x);
*s = 'x'; /* 4. Modification of observer */
free (s); /* 5. Pass observer as only */
s = stx_exposeName (x);
*s = 'x'; /* okay */
free (s); /* 6. Pass exposed as only */
s = stx_observeName (x);
return s; /* 7. Observer storage s returned without qualification: s
** 8. Dependent storage s returned as unqualified: s
*/
}
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