// RUN: %clang_cc1 -fcxx-exceptions -fexperimental-new-constant-interpreter -std=c++20 -verify=both,expected -fcxx-exceptions %s
// RUN: %clang_cc1 -fcxx-exceptions -std=c++20 -verify=both,ref -fcxx-exceptions %s
void test_alignas_operand() {
alignas(8) char dummy;
static_assert(__alignof(dummy) == 8);
}
constexpr int getMinus5() {
int a = 10;
a = -5;
int *p = &a;
return *p;
}
static_assert(getMinus5() == -5, "");
constexpr int assign() {
int m = 10;
int k = 12;
m = (k = 20);
return m;
}
static_assert(assign() == 20, "");
constexpr int pointerAssign() {
int m = 10;
int *p = &m;
*p = 12; // modifies m
return m;
}
static_assert(pointerAssign() == 12, "");
constexpr int pointerDeref() {
int m = 12;
int *p = &m;
return *p;
}
static_assert(pointerDeref() == 12, "");
constexpr int pointerAssign2() {
int m = 10;
int *p = &m;
int **pp = &p;
**pp = 12;
int v = **pp;
return v;
}
static_assert(pointerAssign2() == 12, "");
constexpr int unInitLocal() {
int a;
return a; // both-note {{read of uninitialized object}}
}
static_assert(unInitLocal() == 0, ""); // both-error {{not an integral constant expression}} \
// both-note {{in call to 'unInitLocal()'}}
constexpr int initializedLocal() {
int a;
a = 20;
return a;
}
static_assert(initializedLocal() == 20);
constexpr int initializedLocal2() {
int a[2];
return *a; // both-note {{read of uninitialized object is not allowed in a constant expression}}
}
static_assert(initializedLocal2() == 20); // both-error {{not an integral constant expression}} \
// both-note {{in call to}}
struct Int { int a; };
constexpr int initializedLocal3() {
Int i;
return i.a; // both-note {{read of uninitialized object is not allowed in a constant expression}}
}
static_assert(initializedLocal3() == 20); // both-error {{not an integral constant expression}} \
// both-note {{in call to}}
#if 0
// FIXME: This code should be rejected because we pass an uninitialized value
// as a function parameter.
constexpr int inc(int a) { return a + 1; }
constexpr int f() {
int i;
return inc(i);
}
static_assert(f());
#endif
/// Distinct literals have distinct addresses.
/// see https://github.com/llvm/llvm-project/issues/58754
constexpr auto foo(const char *p) { return p; }
constexpr auto p1 = "test1";
constexpr auto p2 = "test2";
constexpr bool b1 = foo(p1) == foo(p1);
static_assert(b1);
constexpr bool b2 = foo(p1) == foo(p2);
static_assert(!b2);
constexpr auto name1() { return "name1"; }
constexpr auto name2() { return "name2"; }
constexpr auto b3 = name1() == name1(); // ref-error {{must be initialized by a constant expression}} \
// ref-note {{comparison of addresses of literals}}
constexpr auto b4 = name1() == name2();
static_assert(!b4);
namespace UninitializedFields {
class A {
public:
int a; // both-note 4{{subobject declared here}}
constexpr A() {}
};
constexpr A a; // both-error {{must be initialized by a constant expression}} \
// both-note {{subobject 'a' is not initialized}}
constexpr A aarr[2]; // both-error {{must be initialized by a constant expression}} \
// both-note {{subobject 'a' is not initialized}}
class F {
public:
int f; // both-note 3{{subobject declared here}}
constexpr F() {}
constexpr F(bool b) {
if (b)
f = 42;
}
};
constexpr F foo[2] = {true}; // both-error {{must be initialized by a constant expression}} \
// both-note {{subobject 'f' is not initialized}}
constexpr F foo2[3] = {true, false, true}; // both-error {{must be initialized by a constant expression}} \
// both-note {{subobject 'f' is not initialized}}
constexpr F foo3[3] = {true, true, F()}; // both-error {{must be initialized by a constant expression}} \
// both-note {{subobject 'f' is not initialized}}
class Base {
public:
bool b;
int a; // both-note {{subobject declared here}}
constexpr Base() : b(true) {}
};
class Derived : public Base {
public:
constexpr Derived() : Base() {} };
constexpr Derived D; // both-error {{must be initialized by a constant expression}} \
// both-note {{subobject 'a' is not initialized}}
class C2 {
public:
A a;
constexpr C2() {} };
constexpr C2 c2; // both-error {{must be initialized by a constant expression}} \
// both-note {{subobject 'a' is not initialized}}
class C3 {
public:
A a[2];
constexpr C3() {}
};
constexpr C3 c3; // both-error {{must be initialized by a constant expression}} \
// both-note {{subobject 'a' is not initialized}}
class C4 {
public:
bool B[2][3]; // both-note {{subobject declared here}}
constexpr C4(){}
};
constexpr C4 c4; // both-error {{must be initialized by a constant expression}} \
// both-note {{subobject 'B' is not initialized}}
};
namespace ConstThis {
class Foo {
const int T = 12; // both-note {{declared const here}}
int a;
public:
constexpr Foo() {
this->a = 10;
T = 13; // both-error {{cannot assign to non-static data member 'T' with const-qualified type}}
}
};
constexpr Foo F; // both-error {{must be initialized by a constant expression}}
class FooDtor {
int a;
public:
constexpr FooDtor() {
this->a = 10;
}
constexpr ~FooDtor() {
this->a = 12;
}
};
constexpr int foo() {
const FooDtor f;
return 0;
}
static_assert(foo() == 0);
template <bool Good>
struct ctor_test {
int a = 0;
constexpr ctor_test() {
if (Good)
a = 10;
int local = 100 / a; // both-note {{division by zero}}
}
};
template <bool Good>
struct dtor_test {
int a = 0;
constexpr dtor_test() = default;
constexpr ~dtor_test() {
if (Good)
a = 10;
int local = 100 / a; // both-note {{division by zero}}
}
};
constexpr ctor_test<true> good_ctor;
constexpr dtor_test<true> good_dtor;
constexpr ctor_test<false> bad_ctor; // both-error {{must be initialized by a constant expression}} \
// both-note {{in call to}}
constexpr dtor_test<false> bad_dtor; // both-error {{must have constant destruction}} \
// both-note {{in call to}}
};
namespace BaseInit {
struct Base {
int a;
};
struct Intermediate : Base {
int b;
};
struct Final : Intermediate {
int c;
constexpr Final(int a, int b, int c) : c(c) {}
};
static_assert(Final{1, 2, 3}.c == 3, ""); // OK
static_assert(Final{1, 2, 3}.a == 0, ""); // both-error {{not an integral constant expression}} \
// both-note {{read of uninitialized object}}
struct Mixin {
int b;
constexpr Mixin() = default;
constexpr Mixin(int b) : b(b) {}
};
struct Final2 : Base, Mixin {
int c;
constexpr Final2(int a, int b, int c) : Mixin(b), c(c) {}
constexpr Final2(int a, int b, int c, bool) : c(c) {}
};
static_assert(Final2{1, 2, 3}.c == 3, ""); // OK
static_assert(Final2{1, 2, 3}.b == 2, ""); // OK
static_assert(Final2{1, 2, 3}.a == 0, ""); // both-error {{not an integral constant expression}} \
// both-note {{read of uninitialized object}}
struct Mixin3 {
int b;
};
struct Final3 : Base, Mixin3 {
int c;
constexpr Final3(int a, int b, int c) : c(c) { this->b = b; }
constexpr Final3(int a, int b, int c, bool) : c(c) {}
};
static_assert(Final3{1, 2, 3}.c == 3, ""); // OK
static_assert(Final3{1, 2, 3}.b == 2, ""); // OK
static_assert(Final3{1, 2, 3}.a == 0, ""); // both-error {{not an integral constant expression}} \
// both-note {{read of uninitialized object}}
};
namespace Destructors {
class Inc final {
public:
int &I;
constexpr Inc(int &I) : I(I) {}
constexpr ~Inc() {
I++;
}
};
class Dec final {
public:
int &I;
constexpr Dec(int &I) : I(I) {}
constexpr ~Dec() {
I--;
}
};
constexpr int m() {
int i = 0;
{
Inc f1(i);
Inc f2(i);
Inc f3(i);
}
return i;
}
static_assert(m() == 3, "");
constexpr int C() {
int i = 0;
while (i < 10) {
Inc inc(i);
continue;
Dec dec(i);
}
return i;
}
static_assert(C() == 10, "");
constexpr int D() {
int i = 0;
{
Inc i1(i);
{
Inc i2(i);
return i;
}
}
return i;
}
static_assert(D() == 0, "");
constexpr int E() {
int i = 0;
for(;;) {
Inc i1(i);
break;
}
return i;
}
static_assert(E() == 1, "");
/// FIXME: This should be rejected, since we call the destructor
/// twice. However, GCC doesn't care either.
constexpr int ManualDtor() {
int i = 0;
{
Inc I(i); // ref-note {{destroying object 'I' whose lifetime has already ended}}
I.~Inc();
}
return i;
}
static_assert(ManualDtor() == 1, ""); // expected-error {{static assertion failed}} \
// expected-note {{evaluates to '2 == 1'}} \
// ref-error {{not an integral constant expression}} \
// ref-note {{in call to 'ManualDtor()'}}
constexpr void doInc(int &i) {
Inc I(i);
return;
}
constexpr int testInc() {
int i = 0;
doInc(i);
return i;
}
static_assert(testInc() == 1, "");
constexpr void doInc2(int &i) {
Inc I(i);
// No return statement.
}
constexpr int testInc2() {
int i = 0;
doInc2(i);
return i;
}
static_assert(testInc2() == 1, "");
namespace DtorOrder {
class A {
public:
int &I;
constexpr A(int &I) : I(I) {}
constexpr ~A() {
I = 1337;
}
};
class B : public A {
public:
constexpr B(int &I) : A(I) {}
constexpr ~B() {
I = 42;
}
};
constexpr int foo() {
int i = 0;
{
B b(i);
}
return i;
}
static_assert(foo() == 1337);
}
class FieldDtor1 {
public:
Inc I1;
Inc I2;
constexpr FieldDtor1(int &I) : I1(I), I2(I){}
};
constexpr int foo2() {
int i = 0;
{
FieldDtor1 FD1(i);
}
return i;
}
static_assert(foo2() == 2);
class FieldDtor2 {
public:
Inc Incs[3];
constexpr FieldDtor2(int &I) : Incs{Inc(I), Inc(I), Inc(I)} {}
};
constexpr int foo3() {
int i = 0;
{
FieldDtor2 FD2(i);
}
return i;
}
static_assert(foo3() == 3);
struct ArrD {
int index;
int *arr;
int &p;
constexpr ~ArrD() {
arr[p] = index;
++p;
}
};
constexpr bool ArrayOrder() {
int order[3] = {0, 0, 0};
int p = 0;
{
ArrD ds[3] = {
{1, order, p},
{2, order, p},
{3, order, p},
};
// ds will be destroyed.
}
return order[0] == 3 && order[1] == 2 && order[2] == 1;
}
static_assert(ArrayOrder());
// Static members aren't destroyed.
class Dec2 {
public:
int A = 0;
constexpr ~Dec2() {
A++;
}
};
class Foo {
public:
static constexpr Dec2 a;
static Dec2 b;
};
static_assert(Foo::a.A == 0);
constexpr bool f() {
Foo f;
return true;
}
static_assert(Foo::a.A == 0);
static_assert(f());
static_assert(Foo::a.A == 0);
struct NotConstexpr {
NotConstexpr() {}
~NotConstexpr() {}
};
struct Outer {
constexpr Outer() = default;
constexpr ~Outer();
constexpr int foo() {
return 12;
}
constexpr int bar()const {
return Outer{}.foo();
}
static NotConstexpr Val;
};
constexpr Outer::~Outer() {}
constexpr Outer O;
static_assert(O.bar() == 12);
}
namespace BaseAndFieldInit {
struct A {
int a;
};
struct B : A {
int b;
};
struct C : B {
int c;
};
constexpr C c = {1,2,3};
static_assert(c.a == 1 && c.b == 2 && c.c == 3);
}
namespace ImplicitFunction {
struct A {
int a; // ref-note {{subobject declared here}}
};
constexpr int callMe() {
A a;
A b{12};
/// The operator= call here will fail and the diagnostics should be fine.
b = a; // ref-note {{subobject 'a' is not initialized}} \
// expected-note {{read of uninitialized object}} \
// both-note {{in call to}}
return 1;
}
static_assert(callMe() == 1, ""); // both-error {{not an integral constant expression}} \
// both-note {{in call to 'callMe()'}}
}
namespace std {
class strong_ordering {
public:
int n;
static const strong_ordering less, equal, greater;
constexpr bool operator==(int n) const noexcept { return this->n == n;}
constexpr bool operator!=(int n) const noexcept { return this->n != n;}
};
constexpr strong_ordering strong_ordering::less = {-1};
constexpr strong_ordering strong_ordering::equal = {0};
constexpr strong_ordering strong_ordering::greater = {1};
class partial_ordering {
public:
long n;
static const partial_ordering less, equal, greater, equivalent, unordered;
constexpr bool operator==(long n) const noexcept { return this->n == n;}
constexpr bool operator!=(long n) const noexcept { return this->n != n;}
};
constexpr partial_ordering partial_ordering::less = {-1};
constexpr partial_ordering partial_ordering::equal = {0};
constexpr partial_ordering partial_ordering::greater = {1};
constexpr partial_ordering partial_ordering::equivalent = {0};
constexpr partial_ordering partial_ordering::unordered = {-127};
} // namespace std
namespace ThreeWayCmp {
static_assert(1 <=> 2 == -1, "");
static_assert(1 <=> 1 == 0, "");
static_assert(2 <=> 1 == 1, "");
static_assert(1.0 <=> 2.f == -1, "");
static_assert(1.0 <=> 1.0 == 0, "");
static_assert(2.0 <=> 1.0 == 1, "");
constexpr int k = (1 <=> 1, 0); // both-warning {{comparison result unused}}
static_assert(k== 0, "");
/// Pointers.
constexpr int a[] = {1,2,3};
constexpr int b[] = {1,2,3};
constexpr const int *pa1 = &a[1];
constexpr const int *pa2 = &a[2];
constexpr const int *pb1 = &b[1];
static_assert(pa1 <=> pb1 != 0, ""); // both-error {{not an integral constant expression}} \
// both-note {{has unspecified value}}
static_assert(pa1 <=> pa1 == 0, "");
static_assert(pa1 <=> pa2 == -1, "");
static_assert(pa2 <=> pa1 == 1, "");
}
namespace ConstexprArrayInitLoopExprDestructors
{
struct Highlander {
int *p = 0;
constexpr Highlander() {}
constexpr void set(int *p) { this->p = p; ++*p; if (*p != 1) throw "there can be only one"; }
constexpr ~Highlander() { --*p; }
};
struct X {
int *p;
constexpr X(int *p) : p(p) {}
constexpr X(const X &x, Highlander &&h = Highlander()) : p(x.p) {
h.set(p);
}
};
constexpr int f() {
int n = 0;
X x[3] = {&n, &n, &n};
auto [a, b, c] = x;
return n;
}
static_assert(f() == 0);
}
namespace NonPrimitiveOpaqueValue
{
struct X {
int x;
constexpr operator bool() const { return x != 0; }
};
constexpr int ternary() { return X(0) ?: X(0); }
static_assert(!ternary(), "");
}
namespace TryCatch {
constexpr int foo() {
int a = 10;
try {
++a;
} catch(int m) {
--a;
}
return a;
}
static_assert(foo() == 11);
}
namespace IgnoredConstantExpr {
consteval int immediate() { return 0;}
struct ReferenceToNestedMembers {
int m;
int a = ((void)immediate(), m);
int b = ((void)immediate(), this->m);
};
struct ReferenceToNestedMembersTest {
void* m = nullptr;
ReferenceToNestedMembers j{0};
} test_reference_to_nested_members;
}
namespace RewrittenBinaryOperators {
template <class T, T Val>
struct Conv {
constexpr operator T() const { return Val; }
operator T() { return Val; }
};
struct X {
constexpr const Conv<int, -1> operator<=>(X) { return {}; }
};
static_assert(X() < X(), "");
}
namespace GH61417 {
struct A {
unsigned x : 1;
unsigned : 0;
unsigned y : 1;
constexpr A() : x(0), y(0) {}
bool operator==(const A& rhs) const noexcept = default;
};
void f1() {
constexpr A a, b;
constexpr bool c = (a == b); // no diagnostic, we should not be comparing the
// unnamed bit-field which is indeterminate
}
void f2() {
A a, b;
bool c = (a == b); // no diagnostic nor crash during codegen attempting to
// access info for unnamed bit-field
}
}
namespace FailingDestructor {
struct D {
int n;
bool can_destroy;
constexpr ~D() {
if (!can_destroy)
throw "oh no";
}
};
template<D d>
void f() {} // both-note {{invalid explicitly-specified argument}}
void g() {
f<D{0, false}>(); // both-error {{no matching function}}
}
}
void overflowInSwitchCase(int n) {
switch (n) {
case (int)(float)1e300: // both-error {{constant expression}} \
// both-note {{value +Inf is outside the range of representable values of type 'int'}}
break;
}
}
namespace APValues {
int g;
struct A { union { int n, m; }; int *p; int A::*q; char buffer[32]; };
template<A a> constexpr const A &get = a;
constexpr const A &v = get<A{}>;
constexpr const A &w = get<A{1, &g, &A::n, "hello"}>;
}
namespace self_referencing {
struct S {
S* ptr = nullptr;
constexpr S(int i) : ptr(this) {
if (this == ptr && i)
ptr = nullptr;
}
constexpr ~S() {}
};
void test() {
S s(1);
}
}
namespace GH64949 {
struct f {
int g; // both-note {{subobject declared here}}
constexpr ~f() {}
};
class h {
public:
consteval h(char *) {}
f i;
};
void test() { h{nullptr}; } // both-error {{call to consteval function 'GH64949::h::h' is not a constant expression}} \
// both-note {{subobject 'g' is not initialized}} \
// both-warning {{expression result unused}}
}
/// This used to cause an assertion failure inside EvaluationResult::checkFullyInitialized.
namespace CheckingNullPtrForInitialization {
struct X {
consteval operator const char *() const {
return nullptr;
}
};
const char *f() {
constexpr X x;
return x;
}
}
namespace VariadicCallOperator {
class F {
public:
constexpr void operator()(int a, int b, ...) {}
};
constexpr int foo() {
F f;
f(1,2, 3);
return 1;
}
constexpr int A = foo();
}
namespace DefinitionLoc {
struct NonConstexprCopy {
constexpr NonConstexprCopy() = default;
NonConstexprCopy(const NonConstexprCopy &);
constexpr NonConstexprCopy(NonConstexprCopy &&) = default;
int n = 42;
};
NonConstexprCopy::NonConstexprCopy(const NonConstexprCopy &) = default; // both-note {{here}}
constexpr NonConstexprCopy ncc1 = NonConstexprCopy(NonConstexprCopy());
constexpr NonConstexprCopy ncc2 = ncc1; // both-error {{constant expression}} \
// both-note {{non-constexpr constructor}}
}
namespace VirtDtor {
class B {
public:
constexpr B(char *p) : p(p) {}
virtual constexpr ~B() {
*p = 'B';
++p;
}
char *p;
};
class C : public B {
public:
constexpr C(char *p) : B(p) {}
virtual constexpr ~C() override {
*p = 'C';
++p;
}
};
union U {
constexpr U(char *p) : c(p) {}
constexpr ~U() {}
C c;
};
constexpr int test(char a, char b) {
char buff[2] = {};
U u(buff);
/// U is a union, so it won't call the destructor of its fields.
/// We do this manually here. Explicitly calling ~C() here should
/// also call the destructor of the base classes however.
u.c.~C();
return buff[0] == a && buff[1] == b;
}
static_assert(test('C', 'B'));
}
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