[libcxx-commits] [libcxx] [libc++] LWG3223 Broken requirements for shared_ptr converting constructors (PR #93071)
via libcxx-commits
libcxx-commits at lists.llvm.org
Wed May 22 10:17:09 PDT 2024
https://github.com/huixie90 created https://github.com/llvm/llvm-project/pull/93071
None
>From eae0f4ccdc76dfb3a7d4999cc8945ee08ad36895 Mon Sep 17 00:00:00 2001
From: Hui <hui.xie0621 at gmail.com>
Date: Wed, 22 May 2024 18:16:48 +0100
Subject: [PATCH] [libc++] LWG3223 Broken requirements for shared_ptr
converting constructors
---
libcxx/docs/Status/Cxx20Issues.csv | 2 +-
libcxx/include/__memory/shared_ptr.h | 7 ++-
.../nullptr_t_deleter.pass.cpp | 20 ++++++++
.../nullptr_t_deleter_allocator.pass.cpp | 21 ++++++++
.../pointer_deleter.pass.cpp | 36 ++------------
.../pointer_deleter_allocator.pass.cpp | 35 ++------------
.../util.smartptr.shared.const/types.h | 48 +++++++++++++++++++
7 files changed, 102 insertions(+), 67 deletions(-)
create mode 100644 libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/types.h
diff --git a/libcxx/docs/Status/Cxx20Issues.csv b/libcxx/docs/Status/Cxx20Issues.csv
index db57b15256a62..fadbc5c6048f0 100644
--- a/libcxx/docs/Status/Cxx20Issues.csv
+++ b/libcxx/docs/Status/Cxx20Issues.csv
@@ -200,7 +200,7 @@
"`3200 <https://wg21.link/LWG3200>`__","``midpoint``\ should not constrain ``T``\ is complete","Prague","|Nothing To Do|",""
"`3201 <https://wg21.link/LWG3201>`__","``lerp``\ should be marked as ``noexcept``\ ","Prague","|Complete|",""
"`3226 <https://wg21.link/LWG3226>`__","``zoned_time``\ constructor from ``string_view``\ should accept ``zoned_time<Duration2, TimeZonePtr2>``\ ","Prague","","","|chrono|"
-"`3233 <https://wg21.link/LWG3233>`__","Broken requirements for ``shared_ptr``\ converting constructors","Prague","",""
+"`3233 <https://wg21.link/LWG3233>`__","Broken requirements for ``shared_ptr``\ converting constructors","Prague","|Complete|","19.0"
"`3237 <https://wg21.link/LWG3237>`__","LWG 3038 and 3190 have inconsistent PRs","Prague","|Complete|","16.0"
"`3238 <https://wg21.link/LWG3238>`__","Insufficiently-defined behavior of ``std::function``\ deduction guides","Prague","",""
"`3242 <https://wg21.link/LWG3242>`__","``std::format``\ : missing rules for ``arg-id``\ in ``width``\ and ``precision``\ ","Prague","|Complete|","14.0","|format|"
diff --git a/libcxx/include/__memory/shared_ptr.h b/libcxx/include/__memory/shared_ptr.h
index 992b1ba43f100..de5707c4a67b0 100644
--- a/libcxx/include/__memory/shared_ptr.h
+++ b/libcxx/include/__memory/shared_ptr.h
@@ -403,6 +403,9 @@ struct __shared_ptr_deleter_ctor_reqs {
__well_formed_deleter<_Dp, _Yp*>::value;
};
+template <class _Dp, class _Tp>
+using __shared_ptr_nullptr_deleter_ctor_reqs = _And<is_move_constructible<_Dp>, __well_formed_deleter<_Dp, nullptr_t> >;
+
#if defined(_LIBCPP_ABI_ENABLE_SHARED_PTR_TRIVIAL_ABI)
# define _LIBCPP_SHARED_PTR_TRIVIAL_ABI __attribute__((__trivial_abi__))
#else
@@ -498,7 +501,7 @@ class _LIBCPP_SHARED_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS shared_ptr {
#endif // _LIBCPP_HAS_NO_EXCEPTIONS
}
- template <class _Dp>
+ template <class _Dp, __enable_if_t<__shared_ptr_nullptr_deleter_ctor_reqs<_Dp, _Tp>::value, int> = 0 >
_LIBCPP_HIDE_FROM_ABI shared_ptr(nullptr_t __p, _Dp __d) : __ptr_(nullptr) {
#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
try {
@@ -518,7 +521,7 @@ class _LIBCPP_SHARED_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS shared_ptr {
#endif // _LIBCPP_HAS_NO_EXCEPTIONS
}
- template <class _Dp, class _Alloc>
+ template <class _Dp, class _Alloc, __enable_if_t<__shared_ptr_nullptr_deleter_ctor_reqs<_Dp, _Tp>::value, int> = 0 >
_LIBCPP_HIDE_FROM_ABI shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a) : __ptr_(nullptr) {
#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
try {
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter.pass.cpp
index 49497b6956b9f..13340ed5294c0 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter.pass.cpp
@@ -17,6 +17,7 @@
#include "test_macros.h"
#include "deleter_types.h"
+#include "types.h"
struct A
{
static int count;
@@ -28,6 +29,25 @@ struct A
int A::count = 0;
+// LWG 3233. Broken requirements for shared_ptr converting constructors
+// https://cplusplus.github.io/LWG/issue3233
+static_assert( std::is_constructible<std::shared_ptr<int>, std::nullptr_t, test_deleter<int> >::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int>, std::nullptr_t, bad_deleter>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int>, std::nullptr_t, no_nullptr_deleter>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int>, std::nullptr_t, no_move_deleter>::value, "");
+
+#if TEST_STD_VER >= 17
+static_assert( std::is_constructible<std::shared_ptr<int[]>, std::nullptr_t, test_deleter<int> >::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[]>, std::nullptr_t, bad_deleter>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[]>, std::nullptr_t, no_nullptr_deleter>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[]>, std::nullptr_t, no_move_deleter>::value, "");
+
+static_assert( std::is_constructible<std::shared_ptr<int[5]>, std::nullptr_t, test_deleter<int> >::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[5]>, std::nullptr_t, bad_deleter>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[5]>, std::nullptr_t, no_nullptr_deleter>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[5]>, std::nullptr_t, no_move_deleter>::value, "");
+#endif
+
int main(int, char**)
{
{
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator.pass.cpp
index 4e9fc227b99e8..6029f62c0219c 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator.pass.cpp
@@ -17,6 +17,8 @@
#include "test_allocator.h"
#include "min_allocator.h"
+#include "types.h"
+
struct A
{
static int count;
@@ -28,6 +30,25 @@ struct A
int A::count = 0;
+// LWG 3233. Broken requirements for shared_ptr converting constructors
+// https://cplusplus.github.io/LWG/issue3233
+static_assert( std::is_constructible<std::shared_ptr<int>, std::nullptr_t, test_deleter<int>, test_allocator<int> >::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int>, std::nullptr_t, bad_deleter, test_allocator<int>>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int>, std::nullptr_t, no_nullptr_deleter, test_allocator<int>>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int>, std::nullptr_t, no_move_deleter, test_allocator<int>>::value, "");
+
+#if TEST_STD_VER >= 17
+static_assert( std::is_constructible<std::shared_ptr<int[]>, std::nullptr_t, test_deleter<int>, test_allocator<int> >::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[]>, std::nullptr_t, bad_deleter, test_allocator<int>>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[]>, std::nullptr_t, no_nullptr_deleter, test_allocator<int>>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[]>, std::nullptr_t, no_move_deleter, test_allocator<int>>::value, "");
+
+static_assert( std::is_constructible<std::shared_ptr<int[5]>, std::nullptr_t, test_deleter<int>, test_allocator<int> >::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[5]>, std::nullptr_t, bad_deleter, test_allocator<int>>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[5]>, std::nullptr_t, no_nullptr_deleter, test_allocator<int>>::value, "");
+static_assert(!std::is_constructible<std::shared_ptr<int[5]>, std::nullptr_t, no_move_deleter, test_allocator<int>>::value, "");
+#endif
+
int main(int, char**)
{
test_allocator_statistics alloc_stats;
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter.pass.cpp
index 42225a4b0be7e..5720e6a3fe0bb 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter.pass.cpp
@@ -17,6 +17,8 @@
#include "test_macros.h"
#include "deleter_types.h"
+#include "types.h"
+
struct A
{
static int count;
@@ -28,38 +30,8 @@ struct A
int A::count = 0;
-struct bad_ty { };
-
-struct bad_deleter
-{
- void operator()(bad_ty) { }
-};
-
-struct no_move_deleter
-{
- no_move_deleter(no_move_deleter const&) = delete;
- no_move_deleter(no_move_deleter &&) = delete;
- void operator()(int*) { }
-};
-
-static_assert(!std::is_move_constructible<no_move_deleter>::value, "");
-
-struct Base { };
-struct Derived : Base { };
-
-template<class T>
-class MoveDeleter
-{
- MoveDeleter();
- MoveDeleter(MoveDeleter const&);
-public:
- MoveDeleter(MoveDeleter&&) {}
-
- explicit MoveDeleter(int) {}
-
- void operator()(T* ptr) { delete ptr; }
-};
-
+// LWG 3233. Broken requirements for shared_ptr converting constructors
+// https://cplusplus.github.io/LWG/issue3233
// https://llvm.org/PR60258
// Invalid constructor SFINAE for std::shared_ptr's array ctors
static_assert( std::is_constructible<std::shared_ptr<int>, int*, test_deleter<int> >::value, "");
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator.pass.cpp
index a110525b9b922..1c12c533d5be5 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator.pass.cpp
@@ -17,6 +17,7 @@
#include "test_allocator.h"
#include "min_allocator.h"
+#include "types.h"
struct A
{
static int count;
@@ -28,38 +29,8 @@ struct A
int A::count = 0;
-struct bad_ty { };
-
-struct bad_deleter
-{
- void operator()(bad_ty) { }
-};
-
-struct no_move_deleter
-{
- no_move_deleter(no_move_deleter const&) = delete;
- no_move_deleter(no_move_deleter &&) = delete;
- void operator()(int*) { }
-};
-
-static_assert(!std::is_move_constructible<no_move_deleter>::value, "");
-
-struct Base { };
-struct Derived : Base { };
-
-template<class T>
-class MoveDeleter
-{
- MoveDeleter();
- MoveDeleter(MoveDeleter const&);
-public:
- MoveDeleter(MoveDeleter&&) {}
-
- explicit MoveDeleter(int) {}
-
- void operator()(T* ptr) { delete ptr; }
-};
-
+// LWG 3233. Broken requirements for shared_ptr converting constructors
+// https://cplusplus.github.io/LWG/issue3233
// https://llvm.org/PR60258
// Invalid constructor SFINAE for std::shared_ptr's array ctors
static_assert( std::is_constructible<std::shared_ptr<int>, int*, test_deleter<int>, test_allocator<int> >::value, "");
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/types.h b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/types.h
new file mode 100644
index 0000000000000..e01167241cd84
--- /dev/null
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/types.h
@@ -0,0 +1,48 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#ifndef TEST_STD_UTILITIES_MEMORY_UTIL_SMARTPTR_SHARED_CONST_TYPES_H
+#define TEST_STD_UTILITIES_MEMORY_UTIL_SMARTPTR_SHARED_CONST_TYPES_H
+
+#include <type_traits>
+
+struct bad_ty {};
+
+struct bad_deleter {
+ void operator()(bad_ty) {}
+};
+
+struct no_move_deleter {
+ no_move_deleter(no_move_deleter const&) = delete;
+ no_move_deleter(no_move_deleter&&) = delete;
+ void operator()(int*) {}
+};
+
+static_assert(!std::is_move_constructible<no_move_deleter>::value, "");
+
+struct no_nullptr_deleter {
+ void operator()(int*) const {}
+ void operator()(std::nullptr_t) const = delete;
+};
+
+struct Base {};
+struct Derived : Base {};
+
+template <class T>
+class MoveDeleter {
+ MoveDeleter();
+ MoveDeleter(MoveDeleter const&);
+
+public:
+ MoveDeleter(MoveDeleter&&) {}
+
+ explicit MoveDeleter(int) {}
+
+ void operator()(T* ptr) { delete ptr; }
+};
+
+#endif // TEST_STD_UTILITIES_MEMORY_UTIL_SMARTPTR_SHARED_CONST_TYPES_H
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