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/* PR tree-optimization/79376 - wrong lower bound with %s and non-constant
strings in -Wformat-overflow
{ dg-do compile }
{ dg-options "-O2 -fdump-tree-optimized" } */
#define CAT(s, n) s ## n
#define FAIL(line) CAT (failure_on_line_, line)
/* Emit a call to a function named failure_on_line_NNN when EXPR is false. */
#define ASSERT(expr) \
do { \
extern void FAIL (__LINE__)(void); \
if (!(expr)) FAIL (__LINE__)(); \
} while (0)
#define KEEP(line) CAT (keep_call_on_line_, line)
/* Emit a call to a function named keep_call_on_line_NNN when EXPR is true.
Used to verify that the expression need not be the only one that holds. */
#define ASSERT_MAYBE(expr) \
do { \
extern void KEEP (__LINE__)(void); \
if (expr) KEEP (__LINE__)(); \
} while (0)
struct Arrays
{
char a1[1];
char a2[2];
char a3[3];
char a4[4];
char a5[5];
char ax[];
};
void test_arrays (int i, struct Arrays *a)
{
{
const char *s = i < 0 ? a->a3 : a->a1;
int n = __builtin_snprintf (0, 0, "%-s", s);
/* Since it's undefined to pass an unterminated array to a %s
directive it would be valid to assume that S above is not
longer than sizeof (A->A3) but the optimization isn't done
because the GIMPLE representation of the %s argument isn't
suffficiently reliable not to confuse it for some other
array. The argument length is therefore assumed to be in
the range [0, PTRDIFF_MAX - 2] and the sprintf result to be
as big as INT_MAX and possibly even negative if the function
were to fail due to a single directive resulting in more than
the 4,095 byte maximum required to be supported.
ASSERT (0 <= n && n < 3);
*/
ASSERT_MAYBE (0 == n);
ASSERT_MAYBE (1 == n);
ASSERT_MAYBE (2 == n);
}
{
const char *s = i < 0 ? a->a3 : a->a5;
int n = __builtin_snprintf (0, 0, "%-s", s);
/* ASSERT (0 <= n && n < 5); */
ASSERT_MAYBE (0 == n);
ASSERT_MAYBE (1 == n);
ASSERT_MAYBE (2 == n);
ASSERT_MAYBE (3 == n);
ASSERT_MAYBE (4 == n);
}
}
void test_string_and_array (int i, struct Arrays *a)
{
{
const char *s = i < 0 ? a->a3 : "1";
int n = __builtin_snprintf (0, 0, "%-s", s);
/* ASSERT (0 <= n && n < 3); */
ASSERT_MAYBE (0 == n);
ASSERT_MAYBE (1 == n);
ASSERT_MAYBE (2 == n);
}
{
const char *s = i < 0 ? "12" : a->a5;
int n = __builtin_snprintf (0, 0, "%-s", s);
/* ASSERT (0 <= n && n < 5); */
ASSERT_MAYBE (0 == n);
ASSERT_MAYBE (1 == n);
ASSERT_MAYBE (2 == n);
ASSERT_MAYBE (3 == n);
ASSERT_MAYBE (4 == n);
}
{
const char *s = i < 0 ? a->a4 : 0 < i ? "12" : a->a5;
int n = __builtin_snprintf (0, 0, "%-s", s);
/* ASSERT (0 <= n && n < 5); */
ASSERT_MAYBE (0 == n);
ASSERT_MAYBE (1 == n);
ASSERT_MAYBE (2 == n);
ASSERT_MAYBE (3 == n);
ASSERT_MAYBE (4 == n);
}
}
/* { dg-final { scan-tree-dump-not "failure_on_line" "optimized"} }
{ dg-final { scan-tree-dump-times "keep_call_on_line" 21 "optimized"} } */
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