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// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 %s
// New exciting ambiguities in C++11
// final 'context sensitive' mess.
namespace final {
struct S { int n; };
struct T { int n; };
namespace N {
int n;
// These declare variables named final..
extern struct S final;
extern struct S final [[]];
extern struct S final, foo;
struct S final = S();
// This defines a class, not a variable, even though it would successfully
// parse as a variable but not as a class. DR1318's wording suggests that
// this disambiguation is only performed on an ambiguity, but that was not
// the intent.
struct S final { // expected-note {{here}}
int(n) // expected-error {{expected ';'}}
};
// This too.
struct T final : S {}; // expected-error {{base 'S' is marked 'final'}}
}
}
// enum versus bitfield mess.
namespace bitfield {
enum E {};
struct T {
constexpr T() {}
constexpr T(int) {}
constexpr T(T, T, T, T) {}
constexpr T operator=(T) { return *this; }
constexpr operator int() { return 4; }
};
constexpr T a, b, c, d;
struct S1 {
enum E : T ( a = 1, b = 2, c = 3, 4 ); // ok, declares a bitfield
};
// This could be a bit-field.
struct S2 {
enum E : T { a = 1, b = 2, c = 3, 4 }; // expected-error {{non-integral type}} expected-error {{expected '}'}} expected-note {{to match}}
};
struct S3 {
enum E : int { a = 1, b = 2, c = 3, d }; // ok, defines an enum
};
// Ambiguous.
struct S4 {
enum E : int { a = 1 }; // ok, defines an enum
};
// This could be a bit-field, but would be ill-formed due to the anonymous
// member being initialized.
struct S5 {
enum E : int { a = 1 } { b = 2 }; // expected-error {{expected member name}}
};
// This could be a bit-field.
struct S6 {
enum E : int { 1 }; // expected-error {{expected '}'}} expected-note {{to match}}
};
struct U {
constexpr operator T() { return T(); } // expected-note 2{{candidate}}
};
// This could be a bit-field.
struct S7 {
enum E : int { a = U() }; // expected-error {{no viable conversion}}
};
// This could be a bit-field, and does not conform to the grammar of an
// enum definition, because 'id(U())' is not a constant-expression.
constexpr const U &id(const U &u) { return u; }
struct S8 {
enum E : int { a = id(U()) }; // expected-error {{no viable conversion}}
};
}
namespace trailing_return {
typedef int n;
int a;
struct S {
S(int);
S *operator()() const;
int n;
};
namespace N {
void f() {
// This parses as a function declaration, but DR1223 makes the presence of
// 'auto' be used for disambiguation.
S(a)()->n; // ok, expression; expected-warning{{expression result unused}}
auto(a)()->n; // ok, function declaration
using T = decltype(a);
using T = auto() -> n;
}
}
}
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