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/* Verify -Wuse-after-free=2 triggers for conditional as well as
unconditional uses but not for equality expressions. Same as
-Wuse-after-free-5.c but with optimization.
{ dg-do compile }
{ dg-options "-O2 -Wall -Wuse-after-free=2" } */
#if __cplusplus
# define EXTERN_C extern "C"
#else
# define EXTERN_C extern
#endif
EXTERN_C void free (void*);
void sink (void*);
void warn_double_free (void *p)
{
free (p);
free (p); // { dg-warning "pointer 'p' used" }
}
void warn_cond_double_free (void *p, int c)
{
free (p);
if (c)
free (p); // { dg-warning "pointer 'p' may be used" }
}
void warn_call_after_free (void *p)
{
free (p);
sink (p); // { dg-warning "pointer 'p' used" }
}
void warn_cond_call_after_free (void *p, int c)
{
free (p);
if (c)
sink (p); // { dg-warning "pointer 'p' may be used" }
}
void* warn_return_after_free (void *p)
{
free (p);
return p; // { dg-warning "pointer 'p' used" }
}
void* warn_cond_return_after_free (void *p, int c)
{
free (p);
// PHI handling not fully implemented.
if (c)
return p; // { dg-warning "pointer 'p' may be used" "pr??????" { xfail *-*-* } }
return 0;
}
void warn_relational_after_free (char *p, char *q[])
{
free (p);
int a[] =
{
p < q[0], // { dg-warning "pointer 'p' used" }
p <= q[1], // { dg-warning "pointer 'p' used" }
p > q[2], // { dg-warning "pointer 'p' used" }
p >= q[3], // { dg-warning "pointer 'p' used" }
p == q[4],
p != q[5]
};
sink (a);
}
void warn_cond_relational_after_free (char *p, char *q[], int c)
{
free (p);
int a[] =
{
c ? p < q[0] : q[0][0], // { dg-warning "pointer 'p' may be used" }
c ? p <= q[1] : q[1][1], // { dg-warning "pointer 'p' may be used" }
c ? p > q[2] : q[2][2], // { dg-warning "pointer 'p' may be used" }
c ? p >= q[3] : q[3][3], // { dg-warning "pointer 'p' may be used" }
c ? p == q[4] : q[4][4],
c ? p != q[5] : q[5][5],
};
sink (a);
}
// Verify warning for the example in the manual.
struct A { int refcount; void *data; };
void release (struct A *p)
{
int refcount = --p->refcount;
free (p);
if (refcount == 0)
free (p->data); // { dg-warning "pointer 'p' may be used" }
}
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