cxx1z-decomposition.cpp
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// No PCH:
// RUN: %clang_cc1 -pedantic -std=c++1z -include %s -verify %s
//
// With PCH:
// RUN: %clang_cc1 -pedantic -std=c++1z -emit-pch -fallow-pch-with-compiler-errors %s -o %t
// RUN: %clang_cc1 -pedantic -std=c++1z -include-pch %t -fallow-pch-with-compiler-errors -verify %s
// RUN: %clang_cc1 -pedantic -std=c++1z -emit-pch -fallow-pch-with-compiler-errors -fpch-instantiate-templates %s -o %t
// RUN: %clang_cc1 -pedantic -std=c++1z -include-pch %t -fallow-pch-with-compiler-errors -verify %s
#ifndef HEADER
#define HEADER
template<typename T> auto decomp(const T &t) {
auto &[a, b] = t;
return a + b;
}
struct Q { int a, b; };
constexpr int foo(Q &&q) {
auto &[a, b] = q;
return a * 10 + b;
}
auto [noinit]; // expected-error{{decomposition declaration '[noinit]' requires an initializer}}
#else
int arr[2];
int k = decomp(arr);
static_assert(foo({1, 2}) == 12);
// expected-error@15 {{cannot decompose non-class, non-array type 'const int'}}
int z = decomp(10); // expected-note {{instantiation of}}
#endif