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// RUN: %clang_cc1 -std=c++1z -verify %s -fcxx-exceptions -triple=x86_64-linux-gnu
namespace BaseClassAggregateInit {
struct A {
int a, b, c;
constexpr A(int n) : a(n), b(3 * n), c(b - 1) {} // expected-note {{outside the range of representable}}
constexpr A() : A(10) {};
};
struct B : A {};
struct C { int q; };
struct D : B, C { int k; };
constexpr D d1 = { 1, 2, 3 };
static_assert(d1.a == 1 && d1.b == 3 && d1.c == 2 && d1.q == 2 && d1.k == 3);
constexpr D d2 = { 14 };
static_assert(d2.a == 14 && d2.b == 42 && d2.c == 41 && d2.q == 0 && d2.k == 0);
constexpr D d3 = { A(5), C{2}, 1 };
static_assert(d3.a == 5 && d3.b == 15 && d3.c == 14 && d3.q == 2 && d3.k == 1);
constexpr D d4 = {};
static_assert(d4.a == 10 && d4.b == 30 && d4.c == 29 && d4.q == 0 && d4.k == 0);
constexpr D d5 = { __INT_MAX__ }; // expected-error {{must be initialized by a constant expression}}
// expected-note-re@-1 {{in call to 'A({{.*}})'}}
}
namespace NoexceptFunctionTypes {
template<typename T> constexpr bool f() noexcept(true) { return true; }
constexpr bool (*fp)() = f<int>;
static_assert(f<int>());
static_assert(fp());
template<typename T> struct A {
constexpr bool f() noexcept(true) { return true; }
constexpr bool g() { return f(); }
constexpr bool operator()() const noexcept(true) { return true; }
};
static_assert(A<int>().f());
static_assert(A<int>().g());
static_assert(A<int>()());
}
namespace Cxx17CD_NB_GB19 {
const int &r = 0;
constexpr int n = r;
}
namespace PR37585 {
template <class T> struct S { static constexpr bool value = true; };
template <class T> constexpr bool f() { return true; }
template <class T> constexpr bool v = true;
void test() {
if constexpr (true) {}
else if constexpr (f<int>()) {}
else if constexpr (S<int>::value) {}
else if constexpr (v<int>) {}
}
}
// Check that assignment operators evaluate their operands right-to-left.
namespace EvalOrder {
template<typename T> struct lvalue {
T t;
constexpr T &get() { return t; }
};
struct UserDefined {
int n = 0;
constexpr UserDefined &operator=(const UserDefined&) { return *this; }
constexpr UserDefined &operator+=(const UserDefined&) { return *this; }
constexpr void operator<<(const UserDefined&) const {}
constexpr void operator>>(const UserDefined&) const {}
constexpr void operator+(const UserDefined&) const {}
constexpr void operator[](int) const {}
};
constexpr UserDefined ud;
struct NonMember {};
constexpr void operator+=(NonMember, NonMember) {}
constexpr void operator<<(NonMember, NonMember) {}
constexpr void operator>>(NonMember, NonMember) {}
constexpr void operator+(NonMember, NonMember) {}
constexpr NonMember nm;
constexpr void f(...) {}
// Helper to ensure that 'a' is evaluated before 'b'.
struct seq_checker {
bool done_a = false;
bool done_b = false;
template <typename T> constexpr T &&a(T &&v) {
done_a = true;
return (T &&)v;
}
template <typename T> constexpr T &&b(T &&v) {
if (!done_a)
throw "wrong";
done_b = true;
return (T &&)v;
}
constexpr bool ok() { return done_a && done_b; }
};
// SEQ(expr), where part of the expression is tagged A(...) and part is
// tagged B(...), checks that A is evaluated before B.
#define A sc.a
#define B sc.b
#define SEQ(...) static_assert([](seq_checker sc) { void(__VA_ARGS__); return sc.ok(); }({}))
// Longstanding sequencing rules.
SEQ((A(1), B(2)));
SEQ((A(true) ? B(2) : throw "huh?"));
SEQ((A(false) ? throw "huh?" : B(2)));
SEQ(A(true) && B(true));
SEQ(A(false) || B(true));
// From P0145R3:
// Rules 1 and 2 have no effect ('b' is not an expression).
// Rule 3: a->*b
SEQ(A(ud).*B(&UserDefined::n));
SEQ(A(&ud)->*B(&UserDefined::n));
// Rule 4: a(b1, b2, b3)
SEQ(A(f)(B(1), B(2), B(3)));
// Rule 5: b = a, b @= a
SEQ(B(lvalue<int>().get()) = A(0));
SEQ(B(lvalue<UserDefined>().get()) = A(ud));
SEQ(B(lvalue<int>().get()) += A(0));
SEQ(B(lvalue<UserDefined>().get()) += A(ud));
SEQ(B(lvalue<NonMember>().get()) += A(nm));
// Rule 6: a[b]
constexpr int arr[3] = {};
SEQ(A(arr)[B(0)]);
SEQ(A(+arr)[B(0)]);
SEQ(A(0)[B(arr)]);
SEQ(A(0)[B(+arr)]);
SEQ(A(ud)[B(0)]);
// Rule 7: a << b
SEQ(A(1) << B(2));
SEQ(A(ud) << B(ud));
SEQ(A(nm) << B(nm));
// Rule 8: a >> b
SEQ(A(1) >> B(2));
SEQ(A(ud) >> B(ud));
SEQ(A(nm) >> B(nm));
// No particular order of evaluation is specified in other cases, but we in
// practice evaluate left-to-right.
// FIXME: Technically we're expected to check for undefined behavior due to
// unsequenced read and modification and treat it as non-constant due to UB.
SEQ(A(1) + B(2));
SEQ(A(ud) + B(ud));
SEQ(A(nm) + B(nm));
SEQ(f(A(1), B(2)));
#undef SEQ
#undef A
#undef B
}
namespace LambdaCallOp {
constexpr void get_lambda(void (*&p)()) { p = []{}; }
constexpr void call_lambda() {
void (*p)() = nullptr;
get_lambda(p);
p();
}
}
// This used to crash due to an assertion failure,
// see gh#67690
namespace {
struct C {
int x;
};
template <const C *p> void f() {
const auto &[c] = *p;
&c; // expected-warning {{expression result unused}}
}
}
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