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/* PR tree-optimization/101397 - spurious warning writing to the result
of stpcpy minus 1
Verify warnings for indexing into a pointer returned from stpncpy.
The call stpncpy(S1, S2, N) returns the address of the copy of
the first NUL is it exists or &S1[N] otherwise.
{ dg-do compile }
{ dg-options "-O2 -Wall -Wno-stringop-truncation" } */
typedef __SIZE_TYPE__ size_t;
__attribute__ ((alloc_size (1))) const void* alloc (size_t);
void* memchr (const void*, int, size_t);
void sink (int, ...);
extern char ax[], a3[3], a5[5], a7[7], a9[9];
volatile int x;
/* Verify warnings for indexing into the result of memchr. */
void test_memchr (int i, int n, int n3_5, int n3_9)
{
{
/* Because memchr never returns a past-the-end pointer the result
below is in [ax, ax + 4]. */
const char *p = memchr (ax, x, 5);
x = p[-5]; // { dg-warning "\\\[-Warray-bounds" }
x = p[-4];
x = p[-1];
x = p[ 0];
x = p[ 9];
}
{
// The returned pointer is in [ax, ax + n].
const char *p = memchr (ax, x, n);
sink (p[-99], p[-6], p[-5], p[-4], p[-3], p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[99]);
}
{
// The returned pointer is in [a5, a5 + 2].
const char *p = memchr (a5, x, 3);
x = p[-3]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4]);
x = p[ 5]; // { dg-warning "\\\[-Warray-bounds" }
}
{
// The returned pointer is a5 + 4.
const char *p = memchr (a5, x, 4);
x = p[-4]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-3], p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4]);
x = p[ 5]; // { dg-warning "\\\[-Warray-bounds" }
}
{
// The returned pointer is in [a5, a5 + 4].
const char *p = memchr (a5, x, n);
x = p[-5]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-4], p[-3], p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4]);
x = p[ 5]; // { dg-warning "\\\[-Warray-bounds" }
}
{
if (n3_5 < 3 || 5 < n3_5)
n3_5 = 3;
// The returned pointer is in [a7, a7 + 4].
const char *p = memchr (a7, x, n3_5);
x = p[-5]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-4], p[-3], p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4], p[5], p[6]);
x = p[7]; // { dg-warning "\\\[-Warray-bounds" }
}
{
if (n3_9 < 3 || 9 < n3_9)
n3_9 = 3;
// The returned pointer is in [a5, a5 + 4].
const char *p = memchr (a5, x, n3_9);
x = p[-5]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-4], p[-3], p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4]);
x = p[ 5]; // { dg-warning "\\\[-Warray-bounds" }
}
{
const char *p = memchr (a5, x, 4);
if (i > -1) i = -1;
x = p[i];
if (i > -2) i = -2;
x = p[i];
if (i > -3) i = -3;
x = p[i];
if (i > -4) i = -4;
x = p[i]; // { dg-warning "\\\[-Warray-bounds" }
}
}
void test_memchr_in_allocated (int i, int n, int n5_7, int n3_9)
{
if (n5_7 < 5 || 7 < n5_7)
n5_7 = 5;
{
const char *s = alloc (n5_7);
const char *p = memchr (s, x, n);
x = p[-7]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-6], p[-6], p[-5], p[-4], p[-3], p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4], p[5], p[6]);
x = p[7]; // { dg-warning "\\\[-Warray-bounds" }
}
{
const char *s = alloc (n5_7);
const char *p = memchr (s, x, n);
x = p[-7]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-6], p[-5], p[-4], p[-3], p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4], p[5], p[6]);
x = p[7]; // { dg-warning "\\\[-Warray-bounds" }
}
{
const char *s = alloc (n5_7);
const char *p = memchr (s, x, n);
x = p[-7]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-6], p[-5], p[-4], p[-3], p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4], p[5], p[6]);
x = p[7]; // { dg-warning "\\\[-Warray-bounds" }
}
{
const char *s = alloc (n5_7);
const char *p = memchr (s, x, n);
x = p[-7]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-6], p[-5], p[-3], p[-4], p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4], p[5], p[6]);
x = p[7]; // { dg-warning "\\\[-Warray-bounds" }
}
{
const char *s = alloc (n5_7);
const char *p = memchr (s, x, n3_9);
x = p[-7]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-6], p[-5], p[-4], p[-3], p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4], p[5], p[6]);
x = p[7]; // { dg-warning "\\\[-Warray-bounds" }
}
{
const char *s = alloc (n5_7);
const char *p = memchr (s, x, n3_9);
x = p[-7]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-6], p[-5], p[-4], p[-4], p[-2], p[-1], p[0]);
sink (p[1], p[2], p[3], p[4], p[5], p[6]);
x = p[7]; // { dg-warning "\\\[-Warray-bounds" }
}
}
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