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#include <stdio.h>
struct st
{
char *str;
int i;
};
int test_1 (struct st *p)
{
fprintf (stderr, "str: %s\n", p->str); /* { dg-message "pointer 'p' is dereferenced here" } */
if (!p) /* { dg-warning "check of 'p' for NULL after already dereferencing it" } */
return -1;
return p->i;
}
int test_2 (int flag_a, int flag_b, struct st *p)
{
if (flag_a)
{
int j = p->i; /* { dg-message "pointer 'p' is dereferenced here" } */
if (flag_b && p) /* { dg-warning "check of 'p' for NULL after already dereferencing it" } */
return 1;
return j;
}
return 2;
}
int test_3 (struct st *a, struct st *b)
{
if (!a)
return b->i;
if (!b)
return a->i;
return 0;
}
int test_4 (struct st *p)
{
int *q = &p->i;
if (!p)
return -1;
return *q;
}
void test_check_after_strlen (const char *str)
{
size_t len_a = __builtin_strlen (str); /* { dg-message "pointer 'str' is dereferenced here" } */
size_t len_b = str ? __builtin_strlen (str) : 0; /* { dg-warning "check of 'str' for NULL after already dereferencing it" } */
}
void test_6 (struct st *a, struct st *b)
{
int diff = a->i - b->i; /* { dg-message "pointer 'b' is dereferenced here" } */
/* ... */
if (b) /* { dg-warning "check of 'b' for NULL after already dereferencing it" } */
fprintf (stderr, "str: %s\n", b->str);
}
void test_check_after_strcmp (const char *s1, const char *s2)
{
if (!__builtin_strcmp (s1, s2)) /* { dg-message "pointer 's1' is dereferenced here" } */
return;
/* ... */
if (s1) /* { dg-warning "check of 's1' for NULL after already dereferencing it" } */
return;
}
void test_more_than_one_deref (struct st *p)
{
char *str = p->str; /* { dg-message "pointer 'p' is dereferenced here" } */
int i = p->i;
/* ... */
if (p) /* { dg-warning "check of 'p' for NULL after already dereferencing it" } */
return;
/* ... */
}
void test_deref_under_another_name (struct st *p)
{
struct st *q = p;
int i = q->i; /* { dg-message "pointer 'p' is dereferenced here" } */
/* ... */
if (p) /* { dg-warning "check of 'p' for NULL after already dereferencing it" } */
return;
/* ... */
}
void test_check_after_memcpy_src (struct st *dst, struct st *src)
{
__builtin_memcpy (dst, src, sizeof (struct st)); /* { dg-message "pointer 'src' is dereferenced here" } */
/* ... */
if (!src) /* { dg-warning "check of 'src' for NULL after already dereferencing it" } */
return;
/* ... */
}
void test_check_after_memcpy_dst (struct st *dst, struct st *src)
{
__builtin_memcpy (dst, src, sizeof (struct st)); /* { dg-message "pointer 'dst' is dereferenced here" } */
/* ... */
if (!dst) /* { dg-warning "check of 'dst' for NULL after already dereferencing it" } */
return;
/* ... */
}
void test_merger (int *p, int flag)
{
int x = *p;
if (flag)
__builtin_free (p);
if (!flag)
__builtin_free (p); /* { dg-bogus "double-'free'" } */
}
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