blob: 0ddd9ea3046ec078b1bd7c4c46e8b9cb964ca855 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
|
// RUN: %clang_cc1 -std=c++1z -verify %s
void use_from_own_init() {
auto [a] = a; // expected-error {{binding 'a' cannot appear in the initializer of its own decomposition declaration}}
}
// As a Clang extension, _Complex can be decomposed.
float decompose_complex(_Complex float cf) {
static _Complex float scf;
auto &[sre, sim] = scf;
// ok, this is references initialized by constant expressions all the way down
static_assert(&sre == &__real scf);
static_assert(&sim == &__imag scf);
auto [re, im] = cf;
return re*re + im*im;
}
// As a Clang extension, vector types can be decomposed.
typedef float vf3 __attribute__((ext_vector_type(3)));
float decompose_vector(vf3 v) {
auto [x, y, z] = v;
auto *p = &x; // expected-error {{address of vector element requested}}
return x + y + z;
}
struct S { int a, b; };
constexpr int f(S s) {
auto &[a, b] = s;
return a * 10 + b;
}
static_assert(f({1, 2}) == 12);
constexpr bool g(S &&s) {
auto &[a, b] = s;
return &a == &s.a && &b == &s.b && &a != &b;
}
static_assert(g({1, 2}));
// FIXME: by-value array copies
|