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// PR c++/70507 - integer overflow builtins not constant expressions
// { dg-do compile { target c++11 } }
#define SCHAR_MAX __SCHAR_MAX__
#define SHRT_MAX __SHRT_MAX__
#define INT_MAX __INT_MAX__
#define LONG_MAX __LONG_MAX__
#define LLONG_MAX __LONG_LONG_MAX__
#define SCHAR_MIN (-__SCHAR_MAX__ - 1)
#define SHRT_MIN (-__SHRT_MAX__ - 1)
#define INT_MIN (-__INT_MAX__ - 1)
#define LONG_MIN (-__LONG_MAX__ - 1)
#define LLONG_MIN (-__LONG_LONG_MAX__ - 1)
#define UCHAR_MAX (SCHAR_MAX * 2U + 1)
#define USHRT_MAX (SHRT_MAX * 2U + 1)
#define UINT_MAX (INT_MAX * 2U + 1)
#define ULONG_MAX (LONG_MAX * 2LU + 1)
#define ULLONG_MAX (LLONG_MAX * 2LLU + 1)
#define USCHAR_MIN (-__USCHAR_MAX__ - 1)
#define USHRT_MIN (-__USHRT_MAX__ - 1)
#define UINT_MIN (-__UINT_MAX__ - 1)
#define ULONG_MIN (-__ULONG_MAX__ - 1)
#define ULLONG_MIN (-__ULONG_LONG_MAX__ - 1)
#define Assert(expr) static_assert ((expr), #expr)
template <class T>
constexpr T add (T x, T y, T z = T ())
{
return __builtin_add_overflow (x, y, &z) ? 0 : z;
}
template <class T>
constexpr T sub (T x, T y, T z = T ())
{
return __builtin_sub_overflow (x, y, &z) ? 0 : z;
}
template <class T>
constexpr T mul (T x, T y, T z = T ())
{
return __builtin_mul_overflow (x, y, &z) ? 0 : z;
}
#define TEST_ADD(T, x, y, z) Assert (z == add<T>(x, y))
#define TEST_SUB(T, x, y, z) Assert (z == sub<T>(x, y))
#define TEST_MUL(T, x, y, z) Assert (z == mul<T>(x, y))
TEST_ADD (signed char, 0, 0, 0);
TEST_ADD (signed char, 0, SCHAR_MAX, SCHAR_MAX);
TEST_ADD (signed char, 1, SCHAR_MAX, 0); // overflow
TEST_ADD (signed char, SCHAR_MAX, SCHAR_MAX, 0); // overflow
TEST_ADD (signed char, 0, SCHAR_MIN, SCHAR_MIN);
TEST_ADD (signed char, -1, SCHAR_MIN, 0); // overflow
TEST_ADD (short, 0, 0, 0);
TEST_ADD (short, 0, SHRT_MAX, SHRT_MAX);
TEST_ADD (short, 1, SHRT_MAX, 0); // overflow
TEST_ADD (short, SHRT_MAX, SHRT_MAX, 0); // overflow
TEST_ADD (short, 0, SHRT_MIN, SHRT_MIN);
TEST_ADD (short, -1, SHRT_MIN, 0); // overflow
TEST_ADD (short, SHRT_MIN, SHRT_MIN, 0); // overflow
TEST_ADD (int, 0, 0, 0);
TEST_ADD (int, 0, INT_MAX, INT_MAX);
TEST_ADD (int, 1, INT_MAX, 0); // overflow
TEST_ADD (int, INT_MAX, INT_MAX, 0); // overflow
TEST_ADD (int, 0, INT_MIN, INT_MIN);
TEST_ADD (int, -1, INT_MIN, 0); // overflow
TEST_ADD (int, INT_MIN, INT_MIN, 0); // overflow
TEST_ADD (long, 0, 0, 0);
TEST_ADD (long, 0, LONG_MAX, LONG_MAX);
TEST_ADD (long, 1, LONG_MAX, 0); // overflow
TEST_ADD (long, LONG_MAX, LONG_MAX, 0); // overflow
TEST_ADD (long, 0, LONG_MIN, LONG_MIN);
TEST_ADD (long, -1, LONG_MIN, 0); // overflow
TEST_ADD (long, LONG_MIN, LONG_MIN, 0); // overflow
TEST_ADD (long long, 0, 0, 0);
TEST_ADD (long long, 0, LLONG_MAX, LLONG_MAX);
TEST_ADD (long long, 1, LLONG_MAX, 0); // overflow
TEST_ADD (long long, LLONG_MAX, LLONG_MAX, 0); // overflow
TEST_ADD (long long, 0, LLONG_MIN, LLONG_MIN);
TEST_ADD (long long, -1, LLONG_MIN, 0); // overflow
TEST_ADD (long long, LLONG_MIN, LLONG_MIN, 0); // overflow
TEST_ADD (unsigned char, 0, 0, 0);
TEST_ADD (unsigned char, 0, UCHAR_MAX, UCHAR_MAX);
TEST_ADD (unsigned char, 1, UCHAR_MAX, 0); // overflow
TEST_ADD (unsigned char, UCHAR_MAX, UCHAR_MAX, 0); // overflow
TEST_ADD (unsigned short, 0, 0, 0);
TEST_ADD (unsigned short, 0, USHRT_MAX, USHRT_MAX);
TEST_ADD (unsigned short, 1, USHRT_MAX, 0); // overflow
TEST_ADD (unsigned short, USHRT_MAX, USHRT_MAX, 0); // overflow
TEST_ADD (unsigned, 0, 0, 0);
TEST_ADD (unsigned, 0, UINT_MAX, UINT_MAX);
TEST_ADD (unsigned, 1, UINT_MAX, 0); // overflow
TEST_ADD (unsigned, UINT_MAX, UINT_MAX, 0); // overflow
TEST_ADD (unsigned long, 0, 0, 0);
TEST_ADD (unsigned long, 0, ULONG_MAX, ULONG_MAX);
TEST_ADD (unsigned long, 1, ULONG_MAX, 0); // overflow
TEST_ADD (unsigned long, ULONG_MAX, ULONG_MAX, 0); // overflow
TEST_ADD (unsigned long long, 0, 0, 0);
TEST_ADD (unsigned long long, 0, ULLONG_MAX, ULLONG_MAX);
TEST_ADD (unsigned long long, 1, ULLONG_MAX, 0); // overflow
TEST_ADD (unsigned long long, ULLONG_MAX, ULLONG_MAX, 0); // overflow
// Make sure the built-ins are accepted in the following contexts
// where constant expressions are required and that they return
// the expected overflow value.
namespace Enum {
enum Add {
a0 = __builtin_add_overflow_p ( 1, 1, 0),
a1 = __builtin_add_overflow_p (INT_MAX, 1, 0)
};
Assert (a0 == 0);
Assert (a1 == 1);
enum Sub {
s0 = __builtin_sub_overflow_p ( 1, 1, 0),
s1 = __builtin_sub_overflow_p (INT_MIN, 1, 0)
};
Assert (s0 == 0);
Assert (s1 == 1);
enum Mul {
m0 = __builtin_add_overflow_p ( 1, 1, 0),
m1 = __builtin_add_overflow_p (INT_MAX, INT_MAX, 0)
};
Assert (m0 == 0);
Assert (m1 == 1);
} // namespace Enum
namespace TemplateArg {
template <class T, class U, class V,
T x, U y, bool v, bool z = __builtin_add_overflow_p (x, y, V ())>
struct Add {
Assert (z == v);
};
template <class T, class U, class V,
T x, U y, bool v, bool z = __builtin_sub_overflow_p (x, y, V ())>
struct Sub {
Assert (z == v);
};
template <class T, class U, class V,
T x, U y, bool v, bool z = __builtin_mul_overflow_p (x, y, V ())>
struct Mul {
Assert (z == v);
};
template struct Add<int, int, int, 1, 1, false>;
template struct Add<int, int, int, 1, INT_MAX, true>;
template struct Sub<int, int, int, 1, 1, false>;
template struct Sub<int, int, int, -2, INT_MAX, true>;
template struct Mul<int, int, int, 1, 1, false>;
template struct Mul<int, int, int, 2, INT_MAX / 2 + 1, true>;
} // namespace TemplateArg
#if __cplusplus >= 201402L
namespace Initializer {
struct Result {
int res;
bool vflow;
};
constexpr Result
add_vflow (int a, int b)
{
#if 1
Result res = { a + b, __builtin_add_overflow_p (a, b, int ()) };
#else
// The following fails to compile because of c++/71391 - error
// on aggregate initialization with side-effects in a constexpr
// function
int c = 0;
Result res = { 0, __builtin_add_overflow (a, b, &c) };
res.c = c;
#endif
return res;
}
constexpr Result sum = add_vflow (123, 456);
Assert (sum.res == 123 + 456);
Assert (!sum.vflow);
} // namespace Initializer
#endif // __cplusplus >= 201402L
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