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/* PR tree-optimization/101397 - spurious warning writing to the result
of stpcpy minus 1
{ dg-do compile }
{ dg-options "-O2 -Wall" } */
char* stpcpy (char*, const char*);
void sink (int, ...);
extern char ax[], a3[3], a5[5], *s;
volatile int x;
void test_stpcpy (int i)
{
{
char *p = stpcpy (ax, s);
x = p[-9]; // { dg-bogus "\\\[-Warray-bounds" }
x = p[-1]; // { dg-bogus "\\\[-Warray-bounds" }
x = p[ 0];
x = p[+9];
}
{
char *p = stpcpy (a3, s);
x = p[-2]; // { dg-bogus "\\\[-Warray-bounds" }
x = p[-1]; // { dg-bogus "\\\[-Warray-bounds" }
}
{
char *p = stpcpy (a3, s);
x = p[-3]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-2], p[-1], p[0], p[1], p[2]);
x = p[ 3]; // { dg-warning "\\\[-Warray-bounds" }
}
{
/* Stpcpy always returns a pointer to the copied nul (which must
exist) and never a past-the-end pointer. As a result, P below
is in [a5, a5 + 4]. */
char *p = stpcpy (a5, s);
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" }
}
{
char *p = stpcpy (a5 + 1, s);
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]);
x = p[ 4]; // { dg-warning "\\\[-Warray-bounds" }
}
{
char *p = stpcpy (a5 + 2, s);
x = p[-5]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-4], p[-3], p[-2], p[-1], p[0]);
sink (p[1], p[2]);
x = p[ 3]; // { dg-warning "\\\[-Warray-bounds" }
}
{
char *p = stpcpy (a5 + 3, s);
x = p[-5]; // { dg-warning "\\\[-Warray-bounds" }
sink (p[-4], p[-3], p[-2], p[-1], p[0]);
sink (p[1]);
x = p[ 2]; // { dg-warning "\\\[-Warray-bounds" }
}
{
/* Because strlen (a3) is at most 2, the stpcpy call must return
a pointer in the range [ax, ax + 2], and so -3 is necessarily
out of bounds. */
char *p = stpcpy (ax, a3);
p[-3] = 1; // { dg-warning "\\\[-Warray-bounds" }
}
{
if (i >= 0)
i = -1;
char *p = stpcpy (a3, s);
x = p[i]; // { dg-bogus "\\\[-Warray-bounds" }
}
{
if (i >= -3)
i = -3;
char *p = stpcpy (a3, s);
p[i] = 1; // { dg-warning "\\\[-Warray-bounds" }
}
}
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