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// PR c++/69261
// { dg-do run { target c++14 } }
typedef __SIZE_TYPE__ size_t;
template <size_t N>
struct S
{
constexpr S() = default;
template<size_t M>
constexpr S (char const (&d)[M]) : data { 0 }
{
static_assert (M <= N, "size!");
for (size_t i = 0; i != M; i++)
data[i] = d[i];
}
char data[N];
};
template <int N>
constexpr S<N>
s (char const (&d)[N])
{
S<N> c {};
for (size_t i = 0; i != N; i++)
c.data[i] = d[i];
return c;
}
template <size_t N, size_t M>
constexpr auto
concat (S<N> const& s1, S<M> const& s2)
{
S<N+M-1> s (s1.data);
for (size_t i = 0; i != M; i++)
s.data[N + i - 1] = s2.data[i];
return s;
}
template <size_t N, size_t M>
constexpr auto
concat (char const (&x)[N], char const (&y)[M])
{
S<N+M-1> tmp { x };
for (size_t i = 0; i != M; i++)
tmp.data[N+i-1] = y[i];
return tmp;
}
int
main ()
{
auto constexpr s1 = s ("bla");
auto constexpr s2 = s ("blub");
S<8> constexpr s1s2 = concat (s1, s2);
auto constexpr c = concat ("bla", "blub");
if (__builtin_strcmp (s1.data, "bla")
|| __builtin_strcmp (s2.data, "blub")
|| __builtin_strcmp (s1s2.data, "blablub")
|| __builtin_strcmp (c.data, "blablub"))
__builtin_abort ();
}
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