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// UNSUPPORTED: target={{.*}}-zos{{.*}}
// RUN: %clang_cc1 -std=c++20 -fsyntax-only -fcxx-exceptions -verify=ref,ref20,all,all20 %s
// RUN: %clang_cc1 -std=c++23 -fsyntax-only -fcxx-exceptions -verify=ref,ref23,all,all23 %s
// RUN: %clang_cc1 -std=c++20 -fsyntax-only -fcxx-exceptions -verify=expected20,all,all20 %s -fexperimental-new-constant-interpreter
// RUN: %clang_cc1 -std=c++23 -fsyntax-only -fcxx-exceptions -verify=expected23,all,all23 %s -fexperimental-new-constant-interpreter
constexpr int f(int n) { // all20-error {{constexpr function never produces a constant expression}}
static const int m = n; // all-note {{control flows through the definition of a static variable}} \
// all20-note {{control flows through the definition of a static variable}} \
// all20-warning {{is a C++23 extension}}
return m;
}
static_assert(f(0) == 0, ""); // all-error {{not an integral constant expression}} \
// all-note {{in call to}}
constexpr int g(int n) { // all20-error {{constexpr function never produces a constant expression}}
thread_local const int m = n; // all-note {{control flows through the definition of a thread_local variable}} \
// all20-note {{control flows through the definition of a thread_local variable}} \
// all20-warning {{is a C++23 extension}}
return m;
}
static_assert(g(0) == 0, ""); // all-error {{not an integral constant expression}} \
// all-note {{in call to}}
constexpr int c_thread_local(int n) { // all20-error {{constexpr function never produces a constant expression}}
static _Thread_local int m = 0; // all20-note 2{{control flows through the definition of a thread_local variable}} \
// all23-note {{control flows through the definition of a thread_local variable}} \
// all20-warning {{is a C++23 extension}}
return m;
}
static_assert(c_thread_local(0) == 0, ""); // all-error {{not an integral constant expression}} \
// all-note {{in call to}}
constexpr int gnu_thread_local(int n) { // all20-error {{constexpr function never produces a constant expression}}
static __thread int m = 0; // all20-note 2{{control flows through the definition of a thread_local variable}} \
// all23-note {{control flows through the definition of a thread_local variable}} \
// all20-warning {{is a C++23 extension}}
return m;
}
static_assert(gnu_thread_local(0) == 0, ""); // all-error {{not an integral constant expression}} \
// all-note {{in call to}}
constexpr int h(int n) { // all20-error {{constexpr function never produces a constant expression}}
static const int m = n; // all20-note {{control flows through the definition of a static variable}} \
// all20-warning {{is a C++23 extension}}
return &m - &m;
}
constexpr int i(int n) { // all20-error {{constexpr function never produces a constant expression}}
thread_local const int m = n; // all20-note {{control flows through the definition of a thread_local variable}} \
// all20-warning {{is a C++23 extension}}
return &m - &m;
}
constexpr int j(int n) {
if (!n)
return 0;
static const int m = n; // ref20-warning {{is a C++23 extension}} \
// expected20-warning {{is a C++23 extension}}
return m;
}
constexpr int j0 = j(0);
constexpr int k(int n) {
if (!n)
return 0;
thread_local const int m = n; // ref20-warning {{is a C++23 extension}} \
// expected20-warning {{is a C++23 extension}}
return m;
}
constexpr int k0 = k(0);
namespace StaticLambdas {
constexpr auto static_capture_constexpr() {
char n = 'n';
return [n] static { return n; }(); // expected23-error {{a static lambda cannot have any captures}} \
// expected20-error {{a static lambda cannot have any captures}} \
// expected20-warning {{are a C++23 extension}} \
// expected20-warning {{is a C++23 extension}} \
// ref23-error {{a static lambda cannot have any captures}} \
// ref20-error {{a static lambda cannot have any captures}} \
// ref20-warning {{are a C++23 extension}} \
// ref20-warning {{is a C++23 extension}}
}
static_assert(static_capture_constexpr()); // expected23-error {{static assertion expression is not an integral constant expression}} \
// expected20-error {{static assertion expression is not an integral constant expression}} \
// ref23-error {{static assertion expression is not an integral constant expression}} \
// ref20-error {{static assertion expression is not an integral constant expression}}
constexpr auto capture_constexpr() {
char n = 'n';
return [n] { return n; }();
}
static_assert(capture_constexpr());
}
namespace StaticOperators {
auto lstatic = []() static { return 3; }; // ref20-warning {{C++23 extension}} \
// expected20-warning {{C++23 extension}}
static_assert(lstatic() == 3, "");
constexpr int (*f2)(void) = lstatic;
static_assert(f2() == 3);
struct S1 {
constexpr S1() { // all20-error {{never produces a constant expression}}
throw; // all-note {{not valid in a constant expression}} \
// all20-note {{not valid in a constant expression}}
}
static constexpr int operator()() { return 3; } // ref20-warning {{C++23 extension}} \
// expected20-warning {{C++23 extension}}
};
static_assert(S1{}() == 3, ""); // all-error {{not an integral constant expression}} \
// all-note {{in call to}}
}
int test_in_lambdas() {
auto c = [](int n) constexpr {
if (n == 0)
return 0;
else
goto test; // all-note {{subexpression not valid in a constant expression}} \
// all20-warning {{use of this statement in a constexpr function is a C++23 extension}}
test:
return 1;
};
c(0);
constexpr auto A = c(1); // all-error {{must be initialized by a constant expression}} \
// all-note {{in call to}}
return 0;
}
/// PackIndexExpr.
template <auto... p>
struct check_ice {
enum e {
x = p...[0] // all-warning {{is a C++2c extension}}
};
};
static_assert(check_ice<42>::x == 42);
namespace VirtualBases {
namespace One {
struct U { int n; };
struct V : U { int n; };
struct A : virtual V { int n; };
struct Aa { int n; };
struct B : virtual A, Aa {};
struct C : virtual A, Aa {};
struct D : B, C {};
/// Calls the constructor of D.
D d;
}
}
namespace LabelGoto {
constexpr int foo() { // all20-error {{never produces a constant expression}}
a: // all20-warning {{use of this statement in a constexpr function is a C++23 extension}}
goto a; // all20-note 2{{subexpression not valid in a constant expression}} \
// ref23-note {{subexpression not valid in a constant expression}} \
// expected23-note {{subexpression not valid in a constant expression}}
return 1;
}
static_assert(foo() == 1, ""); // all-error {{not an integral constant expression}} \
// all-note {{in call to}}
}
namespace ExplicitLambdaThis {
constexpr auto f = [x = 3]<typename Self>(this Self self) { // all20-error {{explicit object parameters are incompatible with C++ standards before C++2b}}
return x;
};
static_assert(f());
}
namespace std {
struct strong_ordering {
int n;
constexpr operator int() const { return n; }
static const strong_ordering less, equal, greater;
};
constexpr strong_ordering strong_ordering::less = {-1};
constexpr strong_ordering strong_ordering::equal = {0};
constexpr strong_ordering strong_ordering::greater = {1};
}
namespace UndefinedThreeWay {
struct A {
friend constexpr std::strong_ordering operator<=>(const A&, const A&) = default; // all-note {{declared here}}
};
constexpr std::strong_ordering operator<=>(const A&, const A&) noexcept;
constexpr std::strong_ordering (*test_a_threeway)(const A&, const A&) = &operator<=>;
static_assert(!(*test_a_threeway)(A(), A())); // all-error {{static assertion expression is not an integral constant expression}} \
// all-note {{undefined function 'operator<=>' cannot be used in a constant expression}}
}
/// FIXME: The new interpreter is missing the "initializer of q is not a constant expression" diagnostics.a
/// That's because the cast from void* to int* is considered fine, but diagnosed. So we don't consider
/// q to be uninitialized.
namespace VoidCast {
constexpr void* p = nullptr;
constexpr int* q = static_cast<int*>(p); // all-error {{must be initialized by a constant expression}} \
// all-note {{cast from 'void *' is not allowed in a constant expression}} \
// ref-note {{declared here}}
static_assert(q == nullptr); // ref-error {{not an integral constant expression}} \
// ref-note {{initializer of 'q' is not a constant expression}}
}
namespace ExplicitLambdaInstancePointer {
struct C {
constexpr C(auto) { }
};
void foo() {
constexpr auto b = [](this C) { return 1; }; // all20-error {{explicit object parameters are incompatible with C++ standards before C++2b}}
constexpr int (*fp)(C) = b;
static_assert(fp(1) == 1, "");
}
}
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