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// RUN: %clang_cc1 -std=c++2a -verify %s
constexpr int non_class = 42;
constexpr int arr_non_class[5] = {1, 2, 3};
struct A {
int member = 1;
constexpr ~A() { member = member + 1; }
};
constexpr A class_ = {};
constexpr A arr_class[5] = {{}, {}};
struct Mutable {
mutable int member = 1; // expected-note {{declared here}}
constexpr ~Mutable() { member = member + 1; } // expected-note {{read of mutable member}}
};
constexpr Mutable mut_member; // expected-error {{must have constant destruction}} expected-note {{in call}}
struct MutableStore {
mutable int member = 1; // expected-note {{declared here}}
constexpr ~MutableStore() { member = 2; } // expected-note {{assignment to mutable member}}
};
constexpr MutableStore mut_store; // expected-error {{must have constant destruction}} expected-note {{in call}}
// Note: the constant destruction rules disallow this example even though hcm.n is a const object.
struct MutableConst {
struct HasConstMember {
const int n = 4;
};
mutable HasConstMember hcm; // expected-note {{here}}
constexpr ~MutableConst() {
int q = hcm.n; // expected-note {{read of mutable}}
}
};
constexpr MutableConst mc; // expected-error {{must have constant destruction}} expected-note {{in call}}
struct Temporary {
int &&temp;
constexpr ~Temporary() {
int n = temp; // expected-note {{outside the expression that created the temporary}}
}
};
constexpr Temporary t = {3}; // expected-error {{must have constant destruction}} expected-note {{created here}} expected-note {{in call}}
namespace P1073R3 {
consteval int f() { return 42; } // expected-note 2 {{declared here}}
consteval auto g() { return f; }
consteval int h(int (*p)() = g()) { return p(); }
constexpr int r = h();
constexpr auto e = g(); // expected-error {{call to consteval function 'P1073R3::g' is not a constant expression}} \
expected-error {{constexpr variable 'e' must be initialized by a constant expression}} \
expected-note 2 {{pointer to a consteval declaration is not a constant expression}}
static_assert(r == 42);
} // namespace P1073R3
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