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| // RUN: %clang_cc1 -std=c++98 -triple x86_64-unknown-unknown %s -verify -fexceptions -fcxx-exceptions -pedantic-errors \
// RUN: -Wno-variadic-macros -Wno-c11-extensions
// RUN: %clang_cc1 -std=c++11 -triple x86_64-unknown-unknown %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
// RUN: %clang_cc1 -std=c++14 -triple x86_64-unknown-unknown %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
// RUN: %clang_cc1 -std=c++1z -triple x86_64-unknown-unknown %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
#if __cplusplus < 201103L
#define static_assert(...) _Static_assert(__VA_ARGS__)
#endif
namespace dr2083 { // dr2083: partial
#if __cplusplus >= 201103L
void non_const_mem_ptr() {
struct A {
int x;
int y;
};
constexpr A a = {1, 2};
struct B {
int A::*p;
constexpr int g() const {
// OK, not an odr-use of 'a'.
return a.*p;
};
};
static_assert(B{&A::x}.g() == 1, "");
static_assert(B{&A::y}.g() == 2, "");
}
#endif
const int a = 1;
int b;
// Note, references only get special odr-use / constant initializxer
// treatment in C++11 onwards. We continue to apply that even after DR2083.
void ref_to_non_const() {
int c;
const int &ra = a; // expected-note 0-1{{here}}
int &rb = b; // expected-note 0-1{{here}}
int &rc = c; // expected-note {{here}}
struct A {
int f() {
int a = ra;
int b = rb;
#if __cplusplus < 201103L
// expected-error@-3 {{in enclosing function}}
// expected-error@-3 {{in enclosing function}}
#endif
int c = rc; // expected-error {{in enclosing function}}
return a + b + c;
}
};
}
#if __cplusplus >= 201103L
struct NoMut1 { int a, b; };
struct NoMut2 { NoMut1 m; };
struct NoMut3 : NoMut1 {
constexpr NoMut3(int a, int b) : NoMut1{a, b} {}
};
struct Mut1 {
int a;
mutable int b;
};
struct Mut2 { Mut1 m; };
struct Mut3 : Mut1 {
constexpr Mut3(int a, int b) : Mut1{a, b} {}
};
void mutable_subobjects() {
constexpr NoMut1 nm1 = {1, 2};
constexpr NoMut2 nm2 = {1, 2};
constexpr NoMut3 nm3 = {1, 2};
constexpr Mut1 m1 = {1, 2}; // expected-note {{declared here}}
constexpr Mut2 m2 = {1, 2}; // expected-note {{declared here}}
constexpr Mut3 m3 = {1, 2}; // expected-note {{declared here}}
struct A {
void f() {
static_assert(nm1.a == 1, "");
static_assert(nm2.m.a == 1, "");
static_assert(nm3.a == 1, "");
// Can't even access a non-mutable member of a variable containing mutable fields.
static_assert(m1.a == 1, ""); // expected-error {{enclosing function}}
static_assert(m2.m.a == 1, ""); // expected-error {{enclosing function}}
static_assert(m3.a == 1, ""); // expected-error {{enclosing function}}
}
};
}
#endif
void ellipsis() {
void ellipsis(...);
struct A {};
const int n = 0;
#if __cplusplus >= 201103L
constexpr
#endif
A a = {}; // expected-note {{here}}
struct B {
void f() {
ellipsis(n);
// Even though this is technically modelled as an lvalue-to-rvalue
// conversion, it calls a constructor and binds 'a' to a reference, so
// it results in an odr-use.
ellipsis(a); // expected-error {{enclosing function}}
}
};
}
#if __cplusplus >= 201103L
void volatile_lval() {
struct A { int n; };
constexpr A a = {0}; // expected-note {{here}}
struct B {
void f() {
// An lvalue-to-rvalue conversion of a volatile lvalue always results
// in odr-use.
int A::*p = &A::n;
int x = a.*p;
volatile int A::*q = p;
int y = a.*q; // expected-error {{enclosing function}}
}
};
}
#endif
void discarded_lval() {
struct A { int x; mutable int y; volatile int z; };
A a; // expected-note 1+{{here}}
int &r = a.x; // expected-note {{here}}
struct B {
void f() {
a.x; // expected-warning {{unused}}
a.*&A::x; // expected-warning {{unused}}
true ? a.x : a.y; // expected-warning {{unused}}
(void)a.x;
a.x, discarded_lval(); // expected-warning {{unused}}
#if 1 // FIXME: These errors are all incorrect; the above code is valid.
// expected-error@-6 {{enclosing function}}
// expected-error@-6 {{enclosing function}}
// expected-error@-6 2{{enclosing function}}
// expected-error@-6 {{enclosing function}}
// expected-error@-6 {{enclosing function}}
#endif
// 'volatile' qualifier triggers an lvalue-to-rvalue conversion.
a.z; // expected-error {{enclosing function}}
#if __cplusplus < 201103L
// expected-warning@-2 {{assign into a variable}}
#endif
// References always get "loaded" to determine what they reference,
// even if the result is discarded.
r; // expected-error {{enclosing function}} expected-warning {{unused}}
}
};
}
namespace dr_example_1 {
extern int globx;
int main() {
const int &x = globx;
struct A {
#if __cplusplus < 201103L
// expected-error@+2 {{enclosing function}} expected-note@-3 {{here}}
#endif
const int *foo() { return &x; }
} a;
return *a.foo();
}
}
#if __cplusplus >= 201103L
namespace dr_example_2 {
struct A {
int q;
constexpr A(int q) : q(q) {}
constexpr A(const A &a) : q(a.q * 2) {} // (note, not called)
};
int main(void) {
constexpr A a(42);
constexpr int aq = a.q;
struct Q {
int foo() { return a.q; }
} q;
return q.foo();
}
// Checking odr-use does not invent an lvalue-to-rvalue conversion (and
// hence copy construction) on the potential result variable.
struct B {
int b = 42;
constexpr B() {}
constexpr B(const B&) = delete;
};
void f() {
constexpr B b;
struct Q {
constexpr int foo() const { return b.b; }
};
static_assert(Q().foo() == 42, "");
}
}
#endif
}
namespace dr2094 { // dr2094: 5
struct A { int n; };
struct B { volatile int n; };
static_assert(__is_trivially_copyable(volatile int), "");
static_assert(__is_trivially_copyable(const volatile int), "");
static_assert(__is_trivially_copyable(const volatile int[]), "");
static_assert(__is_trivially_copyable(A), "");
static_assert(__is_trivially_copyable(volatile A), "");
static_assert(__is_trivially_copyable(const volatile A), "");
static_assert(__is_trivially_copyable(const volatile A[]), "");
static_assert(__is_trivially_copyable(B), "");
static_assert(__is_trivially_constructible(A, A const&), "");
static_assert(__is_trivially_constructible(B, B const&), "");
static_assert(__is_trivially_assignable(A, const A&), "");
static_assert(__is_trivially_assignable(B, const B&), "");
}
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