// RUN: %clang_cc1 -fexperimental-new-constant-interpreter -verify=expected,both %s
// RUN: %clang_cc1 -std=c++20 -fexperimental-new-constant-interpreter -verify=expected,both %s
// RUN: %clang_cc1 -triple=i686-linux-gnu -std=c++20 -fexperimental-new-constant-interpreter -verify=expected,both %s
// RUN: %clang_cc1 -verify=ref,both %s
// RUN: %clang_cc1 -std=c++20 -verify=ref,both %s
// RUN: %clang_cc1 -triple=i686-linux-gnu -std=c++20 -verify=ref,both %s
#if __cplusplus >= 202002L
constexpr int *Global = new int(12); // both-error {{must be initialized by a constant expression}} \
// both-note {{pointer to heap-allocated object}} \
// both-note {{heap allocation performed here}}
static_assert(*(new int(12)) == 12); // both-error {{not an integral constant expression}} \
// both-note {{allocation performed here was not deallocated}}
constexpr int a() {
new int(12); // both-note {{allocation performed here was not deallocated}}
return 1;
}
static_assert(a() == 1, ""); // both-error {{not an integral constant expression}}
constexpr int b() {
int *i = new int(12);
int m = *i;
delete(i);
return m;
}
static_assert(b() == 12, "");
struct S {
int a;
int b;
static constexpr S *create(int a, int b) {
return new S(a, b);
}
};
constexpr int c() {
S *s = new S(12, 13);
int i = s->a;
delete s;
return i;
}
static_assert(c() == 12, "");
/// Dynamic allocation in function ::create(), freed in function d().
constexpr int d() {
S* s = S::create(12, 14);
int sum = s->a + s->b;
delete s;
return sum;
}
static_assert(d() == 26);
/// Test we emit the right diagnostic for several allocations done on
/// the same site.
constexpr int loop() {
for (int i = 0; i < 10; ++i) {
int *a = new int[10]; // both-note {{not deallocated (along with 9 other memory leaks)}}
}
return 1;
}
static_assert(loop() == 1, ""); // both-error {{not an integral constant expression}}
/// No initializer.
constexpr int noInit() {
int *i = new int;
delete i;
return 0;
}
static_assert(noInit() == 0, "");
/// Try to delete a pointer that hasn't been heap allocated.
constexpr int notHeapAllocated() { // both-error {{never produces a constant expression}}
int A = 0; // both-note 2{{declared here}}
delete &A; // ref-note 2{{delete of pointer '&A' that does not point to a heap-allocated object}} \
// expected-note 2{{delete of pointer '&A' that does not point to a heap-allocated object}}
return 1;
}
static_assert(notHeapAllocated() == 1, ""); // both-error {{not an integral constant expression}} \
// both-note {{in call to 'notHeapAllocated()'}}
consteval int deleteNull() {
int *A = nullptr;
delete A;
return 1;
}
static_assert(deleteNull() == 1, "");
consteval int doubleDelete() { // both-error {{never produces a constant expression}}
int *A = new int;
delete A;
delete A; // both-note 2{{delete of pointer that has already been deleted}}
return 1;
}
static_assert(doubleDelete() == 1); // both-error {{not an integral constant expression}} \
// both-note {{in call to 'doubleDelete()'}}
constexpr int AutoArray() {
auto array = new int[]{0, 1, 2, 3};
int ret = array[3];
delete [] array;
return ret;
}
static_assert(AutoArray() == 3);
#if 0
consteval int largeArray1(bool b) {
if (b) {
int *a = new int[1ull<<32]; // both-note {{cannot allocate array; evaluated array bound 4294967296 is too large}}
delete[] a;
}
return 1;
}
static_assert(largeArray1(false) == 1, "");
static_assert(largeArray1(true) == 1, ""); // both-error {{not an integral constant expression}} \
// both-note {{in call to 'largeArray1(true)'}}
consteval int largeArray2(bool b) {
if (b) {
S *a = new S[1ull<<32]; // both-note {{cannot allocate array; evaluated array bound 4294967296 is too large}}
delete[] a;
}
return 1;
}
static_assert(largeArray2(false) == 1, "");
static_assert(largeArray2(true) == 1, ""); // both-error {{not an integral constant expression}} \
// both-note {{in call to 'largeArray2(true)'}}
#endif
namespace Arrays {
constexpr int d() {
int *Arr = new int[12];
Arr[0] = 1;
Arr[1] = 5;
int sum = Arr[0] + Arr[1];
delete[] Arr;
return sum;
}
static_assert(d() == 6);
constexpr int mismatch1() { // both-error {{never produces a constant expression}}
int *i = new int(12); // both-note {{allocated with 'new' here}} \
// both-note 2{{heap allocation performed here}}
delete[] i; // both-warning {{'delete[]' applied to a pointer that was allocated with 'new'}} \
// both-note 2{{array delete used to delete pointer to non-array object of type 'int'}}
return 6;
}
static_assert(mismatch1() == 6); // both-error {{not an integral constant expression}} \
// both-note {{in call to 'mismatch1()'}}
constexpr int mismatch2() { // both-error {{never produces a constant expression}}
int *i = new int[12]; // both-note {{allocated with 'new[]' here}} \
// both-note 2{{heap allocation performed here}}
delete i; // both-warning {{'delete' applied to a pointer that was allocated with 'new[]'}} \
// both-note 2{{non-array delete used to delete pointer to array object of type 'int[12]'}}
return 6;
}
static_assert(mismatch2() == 6); // both-error {{not an integral constant expression}} \
// both-note {{in call to 'mismatch2()'}}
/// Array of composite elements.
constexpr int foo() {
S *ss = new S[12];
ss[0].a = 12;
int m = ss[0].a;
delete[] ss;
return m;
}
static_assert(foo() == 12);
constexpr int ArrayInit() {
auto array = new int[4]{0, 1, 2, 3};
int ret = array[0];
delete [] array;
return ret;
}
static_assert(ArrayInit() == 0, "");
struct S {
float F;
};
constexpr float ArrayInit2() {
auto array = new S[4]{};
float ret = array[0].F;
delete [] array;
return ret;
}
static_assert(ArrayInit2() == 0.0f, "");
}
namespace std {
struct type_info;
struct destroying_delete_t {
explicit destroying_delete_t() = default;
} inline constexpr destroying_delete{};
struct nothrow_t {
explicit nothrow_t() = default;
} inline constexpr nothrow{};
using size_t = decltype(sizeof(0));
enum class align_val_t : size_t {};
};
[[nodiscard]] void *operator new(std::size_t, const std::nothrow_t&) noexcept;
[[nodiscard]] void *operator new(std::size_t, std::align_val_t, const std::nothrow_t&) noexcept;
[[nodiscard]] void *operator new[](std::size_t, const std::nothrow_t&) noexcept;
[[nodiscard]] void *operator new[](std::size_t, std::align_val_t, const std::nothrow_t&) noexcept;
[[nodiscard]] void *operator new[](std::size_t, std::align_val_t);
void operator delete(void*, const std::nothrow_t&) noexcept;
void operator delete(void*, std::align_val_t, const std::nothrow_t&) noexcept;
void operator delete[](void*, const std::nothrow_t&) noexcept;
void operator delete[](void*, std::align_val_t, const std::nothrow_t&) noexcept;
struct placement_new_arg {};
void *operator new(std::size_t, placement_new_arg);
void operator delete(void*, placement_new_arg);
constexpr void *operator new(std::size_t, void *p) { return p; }
namespace std {
template<typename T> constexpr T *construct(T *p) { return new (p) T; }
template<typename T> constexpr void destroy(T *p) { p->~T(); }
}
namespace PlacementNew {
constexpr int foo() { // both-error {{never produces a constant expression}}
char c[sizeof(int)];
new (c) int{12}; // both-note {{this placement new expression is not supported in constant expressions before C++2c}}
return 0;
}
}
namespace NowThrowNew {
constexpr bool erroneous_array_bound_nothrow(long long n) {
int *p = new (std::nothrow) int[n];
bool result = p != nullptr;
delete[] p;
return result;
}
static_assert(erroneous_array_bound_nothrow(3));
static_assert(erroneous_array_bound_nothrow(0));
static_assert(erroneous_array_bound_nothrow(-1) == 0);
static_assert(!erroneous_array_bound_nothrow(1LL << 62));
struct S { int a; };
constexpr bool erroneous_array_bound_nothrow2(long long n) {
S *p = new (std::nothrow) S[n];
bool result = p != nullptr;
delete[] p;
return result;
}
/// This needs support for CXXConstrucExprs with non-constant array sizes.
static_assert(erroneous_array_bound_nothrow2(3)); // expected-error {{not an integral constant expression}}
static_assert(erroneous_array_bound_nothrow2(0));// expected-error {{not an integral constant expression}}
static_assert(erroneous_array_bound_nothrow2(-1) == 0);// expected-error {{not an integral constant expression}}
static_assert(!erroneous_array_bound_nothrow2(1LL << 62));// expected-error {{not an integral constant expression}}
constexpr bool evaluate_nothrow_arg() {
bool ok = false;
delete new ((ok = true, std::nothrow)) int;
return ok;
}
static_assert(evaluate_nothrow_arg());
}
namespace placement_new_delete {
struct ClassSpecificNew {
void *operator new(std::size_t);
};
struct ClassSpecificDelete {
void operator delete(void*);
};
struct DestroyingDelete {
void operator delete(DestroyingDelete*, std::destroying_delete_t);
};
struct alignas(64) Overaligned {};
constexpr bool ok() {
delete new Overaligned;
delete ::new ClassSpecificNew;
::delete new ClassSpecificDelete;
::delete new DestroyingDelete;
return true;
}
static_assert(ok());
constexpr bool bad(int which) {
switch (which) {
case 0:
delete new (placement_new_arg{}) int; // both-note {{this placement new expression is not supported in constant expressions}}
break;
case 1:
delete new ClassSpecificNew; // both-note {{call to class-specific 'operator new'}}
break;
case 2:
delete new ClassSpecificDelete; // both-note {{call to class-specific 'operator delete'}}
break;
case 3:
delete new DestroyingDelete; // both-note {{call to class-specific 'operator delete'}}
break;
case 4:
// FIXME: This technically follows the standard's rules, but it seems
// unreasonable to expect implementations to support this.
delete new (std::align_val_t{64}) Overaligned; // both-note {{this placement new expression is not supported in constant expressions}}
break;
}
return true;
}
static_assert(bad(0)); // both-error {{constant expression}} \
// both-note {{in call}}
static_assert(bad(1)); // both-error {{constant expression}} both-note {{in call}}
static_assert(bad(2)); // both-error {{constant expression}} both-note {{in call}}
static_assert(bad(3)); // both-error {{constant expression}} both-note {{in call}}
static_assert(bad(4)); // both-error {{constant expression}} \
// both-note {{in call}}
}
namespace delete_random_things {
static_assert((delete new int, true));
static_assert((delete (int*)0, true));
int n; // both-note {{declared here}}
static_assert((delete &n, true)); // both-error {{}} \
// both-note {{delete of pointer '&n' that does not point to a heap-allocated object}}
struct A { int n; };
static_assert((delete &(new A)->n, true)); // both-error {{}} \
// both-note {{delete of pointer to subobject }}
static_assert((delete (new int + 1), true)); // both-error {{}} \
// ref-note {{delete of pointer '&{*new int#0} + 1' that does not point to complete object}} \
// expected-note {{delete of pointer '&{*new int#1} + 1' that does not point to complete object}}
static_assert((delete[] (new int[3] + 1), true)); // both-error {{}} \
// both-note {{delete of pointer to subobject}}
static_assert((delete &(int&)(int&&)0, true)); // both-error {{}} \
// both-note {{delete of pointer '&0' that does not point to a heap-allocated object}} \
// both-note {{temporary created here}}
}
namespace value_dependent_delete {
template<typename T> void f(T *p) {
int arr[(delete p, 0)];
}
}
namespace memory_leaks {
static_assert(*new bool(true)); // both-error {{}} both-note {{allocation performed here was not deallocated}}
constexpr bool *f() { return new bool(true); } // both-note {{allocation performed here was not deallocated}}
static_assert(*f()); // both-error {{}}
struct UP {
bool *p;
constexpr ~UP() { delete p; }
constexpr bool &operator*() { return *p; }
};
constexpr UP g() { return {new bool(true)}; }
static_assert(*g()); // ok
constexpr bool h(UP p) { return *p; }
static_assert(h({new bool(true)})); // ok
}
/// From test/SemaCXX/cxx2a-consteval.cpp
namespace std {
template <typename T> struct remove_reference { using type = T; };
template <typename T> struct remove_reference<T &> { using type = T; };
template <typename T> struct remove_reference<T &&> { using type = T; };
template <typename T>
constexpr typename std::remove_reference<T>::type&& move(T &&t) noexcept {
return static_cast<typename std::remove_reference<T>::type &&>(t);
}
}
namespace cxx2a {
struct A {
int* p = new int(42); // both-note 3{{heap allocation performed here}}
consteval int ret_i() const { return p ? *p : 0; }
consteval A ret_a() const { return A{}; }
constexpr ~A() { delete p; }
};
consteval int by_value_a(A a) { return a.ret_i(); }
consteval int const_a_ref(const A &a) {
return a.ret_i();
}
consteval int rvalue_ref(const A &&a) {
return a.ret_i();
}
consteval const A &to_lvalue_ref(const A &&a) {
return a;
}
void test() {
constexpr A a{ nullptr };
{ int k = A().ret_i(); }
{ A k = A().ret_a(); } // both-error {{'cxx2a::A::ret_a' is not a constant expression}} \
// both-note {{heap-allocated object is not a constant expression}}
{ A k = to_lvalue_ref(A()); } // both-error {{'cxx2a::to_lvalue_ref' is not a constant expression}} \
// both-note {{reference to temporary is not a constant expression}} \
// both-note {{temporary created here}}
{ A k = to_lvalue_ref(A().ret_a()); } // both-error {{'cxx2a::to_lvalue_ref' is not a constant expression}} \
// both-note {{reference to temporary is not a constant expression}} \
// both-note {{temporary created here}}
{ int k = A().ret_a().ret_i(); } // both-error {{'cxx2a::A::ret_a' is not a constant expression}} \
// both-note {{heap-allocated object is not a constant expression}}
{ int k = by_value_a(A()); }
{ int k = const_a_ref(A()); }
{ int k = const_a_ref(a); }
{ int k = rvalue_ref(A()); }
{ int k = rvalue_ref(std::move(a)); }
{ int k = const_a_ref(A().ret_a()); }
{ int k = const_a_ref(to_lvalue_ref(A().ret_a())); }
{ int k = const_a_ref(to_lvalue_ref(std::move(a))); }
{ int k = by_value_a(A().ret_a()); }
{ int k = by_value_a(to_lvalue_ref(static_cast<const A&&>(a))); }
{ int k = (A().ret_a(), A().ret_i()); } // both-error {{'cxx2a::A::ret_a' is not a constant expression}} \
// both-note {{is not a constant expression}} \
// both-warning {{left operand of comma operator has no effect}}
{ int k = (const_a_ref(A().ret_a()), A().ret_i()); } // both-warning {{left operand of comma operator has no effect}}
}
}
constexpr int *const &p = new int; // both-error {{must be initialized by a constant expression}} \
// both-note {{pointer to heap-allocated object}} \
// both-note {{allocation performed here}}
constexpr const int *A[] = {nullptr, nullptr, new int{12}}; // both-error {{must be initialized by a constant expression}} \
// both-note {{pointer to heap-allocated object}} \
// both-note {{allocation performed here}}
struct Sp {
const int *p;
};
constexpr Sp ss[] = {Sp{new int{154}}}; // both-error {{must be initialized by a constant expression}} \
// both-note {{pointer to heap-allocated object}} \
// both-note {{allocation performed here}}
namespace DeleteRunsDtors {
struct InnerFoo {
int *mem;
constexpr ~InnerFoo() {
delete mem;
}
};
struct Foo {
int *a;
InnerFoo IF;
constexpr Foo() {
a = new int(13);
IF.mem = new int(100);
}
constexpr ~Foo() { delete a; }
};
constexpr int abc() {
Foo *F = new Foo();
int n = *F->a;
delete F;
return n;
}
static_assert(abc() == 13);
constexpr int abc2() {
Foo *f = new Foo[3];
delete[] f;
return 1;
}
static_assert(abc2() == 1);
}
/// FIXME: There is a slight difference in diagnostics here.
namespace FaultyDtorCalledByDelete {
struct InnerFoo {
int *mem;
constexpr ~InnerFoo() {
if (mem) {
(void)(1/0); // both-warning {{division by zero is undefined}} \
// both-note {{division by zero}}
}
delete mem;
}
};
struct Foo {
int *a;
InnerFoo IF;
constexpr Foo() {
a = new int(13);
IF.mem = new int(100);
}
constexpr ~Foo() { delete a; } // expected-note {{in call to}}
};
constexpr int abc() {
Foo *F = new Foo();
int n = *F->a;
delete F; // both-note {{in call to}} \
// ref-note {{in call to}}
return n;
}
static_assert(abc() == 13); // both-error {{not an integral constant expression}} \
// both-note {{in call to 'abc()'}}
}
namespace DeleteThis {
constexpr bool super_secret_double_delete() {
struct A {
constexpr ~A() { delete this; } // both-note {{destruction of object that is already being destroyed}} \
// ref-note {{in call to}}
};
delete new A; // both-note {{in call to}}
return true;
}
static_assert(super_secret_double_delete()); // both-error {{not an integral constant expression}} \
// both-note {{in call to 'super_secret_double_delete()'}}
}
/// FIXME: This is currently diagnosed, but should work.
/// If the destructor for S is _not_ virtual however, it should fail.
namespace CastedDelete {
struct S {
constexpr S(int *p) : p(p) {}
constexpr virtual ~S() { *p = 1; }
int *p;
};
struct T: S {
// implicit destructor defined eagerly because it is constexpr and virtual
using S::S;
};
constexpr int vdtor_1() {
int a;
delete (S*)new T(&a); // expected-note {{delete of pointer to subobject}}
return a;
}
static_assert(vdtor_1() == 1); // expected-error {{not an integral constant expression}} \
// expected-note {{in call to}}
}
constexpr void use_after_free_2() { // both-error {{never produces a constant expression}}
struct X { constexpr void f() {} };
X *p = new X;
delete p;
p->f(); // both-note {{member call on heap allocated object that has been deleted}}
}
/// std::allocator definition
namespace std {
using size_t = decltype(sizeof(0));
template<typename T> struct allocator {
constexpr T *allocate(size_t N) {
return (T*)__builtin_operator_new(sizeof(T) * N); // both-note 2{{allocation performed here}} \
// #alloc
}
constexpr void deallocate(void *p) {
__builtin_operator_delete(p); // both-note 2{{std::allocator<...>::deallocate' used to delete pointer to object allocated with 'new'}} \
// both-note {{used to delete a null pointer}}
}
};
template<typename T, typename ...Args>
constexpr void construct_at(void *p, Args &&...args) { // #construct
new (p) T((Args&&)args...);
}
}
/// Specialization for float, using operator new/delete.
namespace std {
using size_t = decltype(sizeof(0));
template<> struct allocator<float> {
constexpr float *allocate(size_t N) {
return (float*)operator new (sizeof(float) * N);
}
constexpr void deallocate(void *p) {
operator delete(p);
}
};
}
namespace OperatorNewDelete {
constexpr bool mismatched(int alloc_kind, int dealloc_kind) {
int *p;
switch (alloc_kind) {
case 0:
p = new int; // both-note {{heap allocation performed here}}
break;
case 1:
p = new int[1]; // both-note {{heap allocation performed here}}
break;
case 2:
p = std::allocator<int>().allocate(1);
break;
}
switch (dealloc_kind) {
case 0:
delete p; // both-note {{'delete' used to delete pointer to object allocated with 'std::allocator<...>::allocate'}}
break;
case 1:
delete[] p; // both-note {{'delete' used to delete pointer to object allocated with 'std::allocator<...>::allocate'}}
break;
case 2:
std::allocator<int>().deallocate(p); // both-note 2{{in call}}
break;
}
return true;
}
static_assert(mismatched(0, 2)); // both-error {{constant expression}} \
// both-note {{in call to}}
static_assert(mismatched(1, 2)); // both-error {{constant expression}} \
// both-note {{in call to}}
static_assert(mismatched(2, 0)); // both-error {{constant expression}} \
// both-note {{in call}}
static_assert(mismatched(2, 1)); // both-error {{constant expression}} \
// both-note {{in call}}
static_assert(mismatched(2, 2));
constexpr bool zeroAlloc() {
int *F = std::allocator<int>().allocate(0);
std::allocator<int>().deallocate(F);
return true;
}
static_assert(zeroAlloc());
/// FIXME: This is broken in the current interpreter.
constexpr int arrayAlloc() {
int *F = std::allocator<int>().allocate(2);
F[0] = 10; // ref-note {{assignment to object outside its lifetime is not allowed in a constant expression}}
F[1] = 13;
int Res = F[1] + F[0];
std::allocator<int>().deallocate(F);
return Res;
}
static_assert(arrayAlloc() == 23); // ref-error {{not an integral constant expression}} \
// ref-note {{in call to}}
struct S {
int i;
constexpr S(int i) : i(i) {}
constexpr ~S() { }
};
/// FIXME: This is broken in the current interpreter.
constexpr bool structAlloc() {
S *s = std::allocator<S>().allocate(1);
s->i = 12; // ref-note {{assignment to object outside its lifetime is not allowed in a constant expression}}
bool Res = (s->i == 12);
std::allocator<S>().deallocate(s);
return Res;
}
static_assert(structAlloc()); // ref-error {{not an integral constant expression}} \
// ref-note {{in call to}}
constexpr bool structAllocArray() {
S *s = std::allocator<S>().allocate(9);
s[2].i = 12; // ref-note {{assignment to object outside its lifetime is not allowed in a constant expression}}
bool Res = (s[2].i == 12);
std::allocator<S>().deallocate(s);
return Res;
}
static_assert(structAllocArray()); // ref-error {{not an integral constant expression}} \
// ref-note {{in call to}}
constexpr bool alloc_from_user_code() {
void *p = __builtin_operator_new(sizeof(int)); // both-note {{cannot allocate untyped memory in a constant expression; use 'std::allocator<T>::allocate'}}
__builtin_operator_delete(p);
return true;
}
static_assert(alloc_from_user_code()); // both-error {{constant expression}} \
// both-note {{in call to}}
constexpr int no_deallocate_nullptr = (std::allocator<int>().deallocate(nullptr), 1); // both-error {{constant expression}} \
// both-note {{in call}}
static_assert((std::allocator<float>().deallocate(std::allocator<float>().allocate(10)), 1) == 1);
}
namespace Limits {
template<typename T>
constexpr T dynarray(int elems, int i) {
T *p;
if constexpr (sizeof(T) == 1)
p = new T[elems]{"fox"};
else
p = new T[elems]{1, 2, 3};
T n = p[i];
delete [] p;
return n;
}
static_assert(dynarray<char>(5, 0) == 'f');
#if __LP64__
template <typename T>
struct S {
constexpr S(unsigned long long N)
: data(nullptr){
data = alloc.allocate(N); // both-note {{in call to 'this->alloc.allocate(18446744073709551615)}}
}
constexpr T operator[](std::size_t i) const {
return data[i];
}
constexpr ~S() {
alloc.deallocate(data);
}
std::allocator<T> alloc;
T* data;
};
constexpr std::size_t s = S<std::size_t>(~0UL)[42]; // both-error {{constexpr variable 's' must be initialized by a constant expression}} \
// both-note@#alloc {{cannot allocate array; evaluated array bound 2305843009213693951 is too large}} \
// both-note {{in call to}}
#endif
}
/// Just test that we reject placement-new expressions before C++2c.
/// Tests for successful expressions are in placement-new.cpp
namespace Placement {
consteval auto ok1() { // both-error {{never produces a constant expression}}
bool b;
new (&b) bool(true); // both-note 2{{this placement new expression is not supported in constant expressions before C++2c}}
return b;
}
static_assert(ok1()); // both-error {{not an integral constant expression}} \
// both-note {{in call to}}
/// placement-new should be supported before C++26 in std functions.
constexpr int ok2() {
int *I = new int;
std::construct_at<int>(I);
int r = *I;
delete I;
return r;
}
static_assert(ok2()== 0);
}
#else
/// Make sure we reject this prior to C++20
constexpr int a() { // both-error {{never produces a constant expression}}
delete new int(12); // both-note 2{{dynamic memory allocation is not permitted in constant expressions until C++20}}
return 1;
}
static_assert(a() == 1, ""); // both-error {{not an integral constant expression}} \
// both-note {{in call to 'a()'}}
static_assert(true ? *new int : 4, ""); // both-error {{expression is not an integral constant expression}} \
// both-note {{read of uninitialized object is not allowed in a constant expression}}
#endif
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