diff --git a/libcxx/include/compare b/libcxx/include/compare
--- a/libcxx/include/compare
+++ b/libcxx/include/compare
@@ -121,6 +121,7 @@
 */
 
 #include <__config>
+#include <concepts>
 #include <type_traits>
 
 #ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
@@ -482,6 +483,32 @@
 template<class _Tp> constexpr weak_ordering weak_order(const _Tp& __lhs, const _Tp& __rhs);
 template<class _Tp> constexpr partial_ordering partial_order(const _Tp& __lhs, const _Tp& __rhs);
 
+template<class _Tp, class _Cat>
+concept __compares_as =                 // exposition only
+  same_as<common_comparison_category_t<_Tp, _Cat>, _Cat>;
+
+template<class _Tp, class _Cat = partial_ordering>
+concept three_way_comparable =
+  __weakly_equality_comparable_with<_Tp, _Tp> &&
+  __partially_ordered_with<_Tp, _Tp> &&
+  requires(__make_const_lvalue_ref<_Tp> __a, __make_const_lvalue_ref<_Tp> __b) {
+    { __a <=> __b } -> __compares_as<_Cat>;
+  };
+
+template<class _Tp, class _Up, class _Cat = partial_ordering>
+concept three_way_comparable_with =
+  three_way_comparable<_Tp, _Cat> &&
+  three_way_comparable<_Up, _Cat> &&
+  common_reference_with<__make_const_lvalue_ref<_Tp>, __make_const_lvalue_ref<_Up>> &&
+  three_way_comparable<
+    common_reference_t<__make_const_lvalue_ref<_Tp>, __make_const_lvalue_ref<_Up>>, _Cat> &&
+  __weakly_equality_comparable_with<_Tp, _Up> &&
+  __partially_ordered_with<_Tp, _Up> &&
+  requires(__make_const_lvalue_ref<_Tp> __t, __make_const_lvalue_ref<_Up> __u) {
+    { __t <=> __u } -> __compares_as<_Cat>;
+    { __u <=> __t } -> __compares_as<_Cat>;
+  };
+
 #endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_SPACESHIP_OPERATOR)
 
 _LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/utility b/libcxx/include/utility
--- a/libcxx/include/utility
+++ b/libcxx/include/utility
@@ -211,7 +211,9 @@
 #include <__debug>
 #include <__tuple>
 #include <__utility/to_underlying.h>
-#include <compare>
+// FIXME (rarutyun): return back <compare> include when
+//                   cyclic dependency for this header is resolved
+// #include <compare>
 #include <cstddef>
 #include <cstdint>
 #include <cstring>
diff --git a/libcxx/test/libcxx/inclusions/utility.inclusions.compile.pass.cpp b/libcxx/test/libcxx/inclusions/utility.inclusions.compile.pass.cpp
--- a/libcxx/test/libcxx/inclusions/utility.inclusions.compile.pass.cpp
+++ b/libcxx/test/libcxx/inclusions/utility.inclusions.compile.pass.cpp
@@ -22,7 +22,9 @@
  #   error "<utility> was expected to define _LIBCPP_UTILITY"
 #endif
 #if TEST_STD_VER > 17 && !defined(_LIBCPP_COMPARE)
- #   error "<utility> should include <compare> in C++20 and later"
+// FIXME (rarutyun): enable this test part when cyclic dependency for
+// <compare> header is resolved
+//  #   error "<utility> should include <compare> in C++20 and later"
 #endif
 #if TEST_STD_VER > 03 && !defined(_LIBCPP_INITIALIZER_LIST)
  #   error "<utility> should include <initializer_list> in C++11 and later"
diff --git a/libcxx/test/std/language.support/cmp/cmp.concept/three_way_comparable.compile.pass.cpp b/libcxx/test/std/language.support/cmp/cmp.concept/three_way_comparable.compile.pass.cpp
new file mode 100644
--- /dev/null
+++ b/libcxx/test/std/language.support/cmp/cmp.concept/three_way_comparable.compile.pass.cpp
@@ -0,0 +1,230 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17
+// UNSUPPORTED: libcpp-no-concepts
+
+// template<class T, class Cat = partial_ordering>
+// concept three_way_comparable = // see below
+
+#include <compare>
+
+#include "compare_types.h"
+
+namespace fundamentals {
+// with default ordering
+static_assert(std::three_way_comparable<int>);
+static_assert(std::three_way_comparable<double>);
+static_assert(std::three_way_comparable<void*>);
+static_assert(std::three_way_comparable<char*>);
+static_assert(std::three_way_comparable<char const*>);
+static_assert(std::three_way_comparable<char volatile*>);
+static_assert(std::three_way_comparable<char const volatile*>);
+static_assert(std::three_way_comparable<wchar_t&>);
+#ifndef _LIBCPP_HAS_NO_CHAR8_T
+static_assert(std::three_way_comparable<char8_t const&>);
+#endif
+#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
+static_assert(std::three_way_comparable<char16_t volatile&>);
+static_assert(std::three_way_comparable<char32_t const volatile&>);
+#endif
+#ifndef _LIBCPP_HAS_NO_INT128
+static_assert(std::three_way_comparable<__int128_t const&>);
+static_assert(std::three_way_comparable<__uint128_t const&>);
+#endif
+static_assert(std::three_way_comparable<unsigned char&&>);
+static_assert(std::three_way_comparable<unsigned short const&&>);
+static_assert(std::three_way_comparable<unsigned int volatile&&>);
+static_assert(std::three_way_comparable<unsigned long const volatile&&>);
+
+// with explicit ordering
+static_assert(std::three_way_comparable<int, std::strong_ordering>);
+static_assert(std::three_way_comparable<int, std::weak_ordering>);
+static_assert(std::three_way_comparable<double, std::partial_ordering>);
+static_assert(!std::three_way_comparable<double, std::weak_ordering>);
+static_assert(std::three_way_comparable<void*, std::strong_ordering>);
+static_assert(std::three_way_comparable<void*, std::weak_ordering>);
+static_assert(std::three_way_comparable<char*, std::strong_ordering>);
+static_assert(std::three_way_comparable<char*, std::weak_ordering>);
+static_assert(std::three_way_comparable<char const*, std::strong_ordering>);
+static_assert(std::three_way_comparable<char const*, std::weak_ordering>);
+static_assert(std::three_way_comparable<char volatile*, std::strong_ordering>);
+static_assert(std::three_way_comparable<char volatile*, std::weak_ordering>);
+static_assert(std::three_way_comparable<char const volatile*, std::strong_ordering>);
+static_assert(std::three_way_comparable<char const volatile*, std::weak_ordering>);
+static_assert(std::three_way_comparable<wchar_t&, std::strong_ordering>);
+static_assert(std::three_way_comparable<wchar_t&, std::weak_ordering>);
+static_assert(std::three_way_comparable<char8_t const&, std::strong_ordering>);
+static_assert(std::three_way_comparable<char8_t const&, std::weak_ordering>);
+static_assert(std::three_way_comparable<char16_t volatile&, std::strong_ordering>);
+static_assert(std::three_way_comparable<char16_t volatile&, std::weak_ordering>);
+static_assert(std::three_way_comparable<char32_t const volatile&, std::strong_ordering>);
+static_assert(std::three_way_comparable<char32_t const volatile&, std::weak_ordering>);
+static_assert(std::three_way_comparable<unsigned char&&, std::strong_ordering>);
+static_assert(std::three_way_comparable<unsigned char&&, std::weak_ordering>);
+static_assert(std::three_way_comparable<unsigned short const&&, std::strong_ordering>);
+static_assert(std::three_way_comparable<unsigned short const&&, std::weak_ordering>);
+static_assert(std::three_way_comparable<unsigned int volatile&&, std::strong_ordering>);
+static_assert(std::three_way_comparable<unsigned int volatile&&, std::weak_ordering>);
+static_assert(std::three_way_comparable<unsigned long const volatile&&, std::strong_ordering>);
+static_assert(std::three_way_comparable<unsigned long const volatile&&, std::weak_ordering>);
+
+static_assert(!std::three_way_comparable<int[5]>);
+static_assert(!std::three_way_comparable<int (*)(int)>);
+static_assert(!std::three_way_comparable<int (&)(int)>);
+static_assert(!std::three_way_comparable<int (*)(int) noexcept>);
+static_assert(!std::three_way_comparable<int (&)(int) noexcept>);
+static_assert(!std::three_way_comparable<std::nullptr_t>);
+
+struct S {};
+static_assert(!std::three_way_comparable<int S::*>);
+static_assert(!std::three_way_comparable<int (S::*)()>);
+static_assert(!std::three_way_comparable<int (S::*)() noexcept>);
+static_assert(!std::three_way_comparable<int (S::*)() &>);
+static_assert(!std::three_way_comparable<int (S::*)() & noexcept>);
+static_assert(!std::three_way_comparable<int (S::*)() &&>);
+static_assert(!std::three_way_comparable<int (S::*)() && noexcept>);
+static_assert(!std::three_way_comparable<int (S::*)() const>);
+static_assert(!std::three_way_comparable<int (S::*)() const noexcept>);
+static_assert(!std::three_way_comparable<int (S::*)() const&>);
+static_assert(!std::three_way_comparable<int (S::*)() const & noexcept>);
+static_assert(!std::three_way_comparable<int (S::*)() const&&>);
+static_assert(!std::three_way_comparable<int (S::*)() const && noexcept>);
+static_assert(!std::three_way_comparable<int (S::*)() volatile>);
+static_assert(!std::three_way_comparable<int (S::*)() volatile noexcept>);
+static_assert(!std::three_way_comparable<int (S::*)() volatile&>);
+static_assert(!std::three_way_comparable<int (S::*)() volatile & noexcept>);
+static_assert(!std::three_way_comparable<int (S::*)() volatile&&>);
+static_assert(!std::three_way_comparable<int (S::*)() volatile && noexcept>);
+static_assert(!std::three_way_comparable<int (S::*)() const volatile>);
+static_assert(!std::three_way_comparable<int (S::*)() const volatile noexcept>);
+static_assert(!std::three_way_comparable<int (S::*)() const volatile&>);
+static_assert(!std::three_way_comparable<int (S::*)() const volatile & noexcept>);
+static_assert(!std::three_way_comparable<int (S::*)() const volatile&&>);
+static_assert(
+    !std::three_way_comparable<int (S::*)() const volatile && noexcept>);
+
+static_assert(!std::three_way_comparable<void>);
+} // namespace fundamentals
+
+namespace user_defined {
+
+struct S {
+    auto operator<=>(const S&) const = default;
+};
+
+static_assert(std::three_way_comparable<S>);
+static_assert(std::three_way_comparable<S, std::strong_ordering>);
+static_assert(std::three_way_comparable<S, std::partial_ordering>);
+
+struct SpaceshipNotDeclared {
+};
+
+static_assert(!std::three_way_comparable<SpaceshipNotDeclared>);
+
+struct SpaceshipDeleted {
+    auto operator<=>(const SpaceshipDeleted&) const = delete;
+};
+
+static_assert(!std::three_way_comparable<SpaceshipDeleted>);
+
+struct SpaceshipWithoutEqualityOperator {
+    auto operator<=>(const SpaceshipWithoutEqualityOperator&) const;
+};
+
+static_assert(!std::three_way_comparable<SpaceshipWithoutEqualityOperator>);
+
+struct EqualityOperatorDeleted {
+    bool operator==(const EqualityOperatorDeleted&) const = delete;
+};
+
+static_assert(!std::three_way_comparable<EqualityOperatorDeleted>);
+
+struct EqualityOperatorOnly {
+    bool operator==(const EqualityOperatorOnly&) const = default;
+};
+
+static_assert(!std::three_way_comparable<EqualityOperatorOnly>);
+
+struct SpaceshipDeclaredEqualityOperatorDeleted {
+    bool operator==(const SpaceshipDeclaredEqualityOperatorDeleted&) const = delete;
+    auto operator<=>(const SpaceshipDeclaredEqualityOperatorDeleted&) const = default;
+};
+
+static_assert(!std::three_way_comparable<SpaceshipDeclaredEqualityOperatorDeleted>);
+
+struct AllInequalityOperators {
+    bool operator<(const AllInequalityOperators&) const;
+    bool operator<=(const AllInequalityOperators&) const;
+    bool operator>(const AllInequalityOperators&) const;
+    bool operator>=(const AllInequalityOperators&) const;
+    bool operator!=(const AllInequalityOperators&) const;
+};
+
+static_assert(!std::three_way_comparable<AllInequalityOperators>);
+
+struct AllComparisonOperators {
+    bool operator<(const AllComparisonOperators&) const;
+    bool operator<=(const AllComparisonOperators&) const;
+    bool operator>(const AllComparisonOperators&) const;
+    bool operator>=(const AllComparisonOperators&) const;
+    bool operator!=(const AllComparisonOperators&) const;
+    bool operator==(const AllComparisonOperators&) const;
+};
+
+static_assert(!std::three_way_comparable<AllComparisonOperators>);
+
+struct AllButOneInequalityOperators {
+    bool operator<(const AllButOneInequalityOperators&) const;
+    bool operator<=(const AllButOneInequalityOperators&) const;
+    bool operator>(const AllButOneInequalityOperators&) const;
+    bool operator!=(const AllButOneInequalityOperators&) const;
+};
+
+static_assert(!std::three_way_comparable<AllButOneInequalityOperators>);
+
+struct AllInequalityOperatorsOneDeleted {
+    bool operator<(const AllInequalityOperatorsOneDeleted&) const;
+    bool operator<=(const AllInequalityOperatorsOneDeleted&) const;
+    bool operator>(const AllInequalityOperatorsOneDeleted&) const;
+    bool operator>=(const AllInequalityOperatorsOneDeleted&) const = delete;
+    bool operator!=(const AllInequalityOperatorsOneDeleted&) const;
+};
+
+static_assert(!std::three_way_comparable<AllInequalityOperatorsOneDeleted>);
+
+struct EqualityOperatorWrongReturnType {
+    int operator==(const EqualityOperatorWrongReturnType&);
+    auto operator<=>(const EqualityOperatorWrongReturnType&) const = default;
+};
+
+static_assert(!std::three_way_comparable<EqualityOperatorWrongReturnType>);
+
+struct SpaceshipWrongReturnType {
+    bool operator==(const SpaceshipWrongReturnType&) const = default;
+    int operator<=>(const SpaceshipWrongReturnType&);
+};
+
+static_assert(!std::three_way_comparable<SpaceshipWrongReturnType>);
+
+struct EqualityOperatorNonConstArgument {
+    bool operator==(EqualityOperatorNonConstArgument&);
+    auto operator<=>(const EqualityOperatorNonConstArgument&) const = default;
+};
+
+static_assert(!std::three_way_comparable<EqualityOperatorNonConstArgument>);
+
+struct SpaceshipNonConstArgument {
+    bool operator==(const SpaceshipNonConstArgument&) const = default;
+    auto operator<=>(SpaceshipNonConstArgument&);
+};
+
+static_assert(!std::three_way_comparable<SpaceshipNonConstArgument>);
+}
+
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/cmp/cmp.concept/three_way_comparable_with.compile.pass.cpp b/libcxx/test/std/language.support/cmp/cmp.concept/three_way_comparable_with.compile.pass.cpp
new file mode 100644
--- /dev/null
+++ b/libcxx/test/std/language.support/cmp/cmp.concept/three_way_comparable_with.compile.pass.cpp
@@ -0,0 +1,242 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17
+// UNSUPPORTED: libcpp-no-concepts
+
+// template<class T, class U, class Cat = partial_ordering>
+// concept three_way_comparable_with = // see below
+
+#include <compare>
+
+#include "compare_types.h"
+
+template <class T, class U = T, typename Cat = std::partial_ordering>
+constexpr bool check_three_way_comparable_with() {
+  constexpr bool result = std::three_way_comparable_with<T, U, Cat>;
+  static_assert(std::three_way_comparable_with<U, T, Cat> == result);
+  static_assert(std::three_way_comparable_with<T, U const, Cat> == result);
+  static_assert(std::three_way_comparable_with<T const, U const, Cat> == result);
+  static_assert(std::three_way_comparable_with<T, U const&, Cat> == result);
+  static_assert(std::three_way_comparable_with<T const, U const&, Cat> == result);
+  static_assert(std::three_way_comparable_with<T, U const&&, Cat> == result);
+  static_assert(std::three_way_comparable_with<T const, U const&&, Cat> == result);
+  if constexpr (!std::is_void_v<T>) {
+    static_assert(std::three_way_comparable_with<T&, U const, Cat> == result);
+    static_assert(std::three_way_comparable_with<T const&, U const, Cat> == result);
+    static_assert(std::three_way_comparable_with<T&, U const&, Cat> == result);
+    static_assert(std::three_way_comparable_with<T const&, U const&, Cat> == result);
+    static_assert(std::three_way_comparable_with<T&, U const&&, Cat> == result);
+    static_assert(std::three_way_comparable_with<T const&, U const&&, Cat> == result);
+    static_assert(std::three_way_comparable_with<T&&, U const, Cat> == result);
+    static_assert(std::three_way_comparable_with<T const&&, U const, Cat> == result);
+    static_assert(std::three_way_comparable_with<T&&, U const&, Cat> == result);
+    static_assert(std::three_way_comparable_with<T const&&, U const&, Cat> == result);
+    static_assert(std::three_way_comparable_with<T&&, U const&&, Cat> == result);
+    static_assert(std::three_way_comparable_with<T const&&, U const&&, Cat> == result);
+  }
+  return result;
+}
+
+namespace fundamentals {
+static_assert(check_three_way_comparable_with<int, int>());
+static_assert(check_three_way_comparable_with<int, char>());
+static_assert(check_three_way_comparable_with<int, wchar_t>());
+static_assert(check_three_way_comparable_with<int, double>());
+static_assert(check_three_way_comparable_with<int*, int*>());
+
+static_assert(check_three_way_comparable_with<int, int, std::strong_ordering>());
+static_assert(check_three_way_comparable_with<int, char, std::strong_ordering>());
+static_assert(check_three_way_comparable_with<int, wchar_t, std::strong_ordering>());
+
+static_assert(check_three_way_comparable_with<int, int, std::weak_ordering>());
+static_assert(check_three_way_comparable_with<int, char, std::weak_ordering>());
+static_assert(check_three_way_comparable_with<int, wchar_t, std::weak_ordering>());
+
+static_assert(!check_three_way_comparable_with<int, bool>());
+static_assert(!check_three_way_comparable_with<int, int*>());
+static_assert(!check_three_way_comparable_with<int, int[5]>());
+static_assert(!check_three_way_comparable_with<int, int (*)()>());
+static_assert(!check_three_way_comparable_with<int, int (&)()>());
+struct S {};
+static_assert(!check_three_way_comparable_with<int, int S::*>());
+static_assert(!check_three_way_comparable_with<int, int (S::*)()>());
+static_assert(!check_three_way_comparable_with<int, int (S::*)() noexcept>());
+static_assert(!check_three_way_comparable_with<int, int (S::*)() const>());
+static_assert(
+    !check_three_way_comparable_with<int, int (S::*)() const noexcept>());
+static_assert(!check_three_way_comparable_with<int, int (S::*)() volatile>());
+static_assert(
+    !check_three_way_comparable_with<int, int (S::*)() volatile noexcept>());
+static_assert(
+    !check_three_way_comparable_with<int, int (S::*)() const volatile>());
+static_assert(!check_three_way_comparable_with<
+              int, int (S::*)() const volatile noexcept>());
+static_assert(!check_three_way_comparable_with<int, int (S::*)() &>());
+static_assert(!check_three_way_comparable_with<int, int (S::*)() & noexcept>());
+static_assert(!check_three_way_comparable_with<int, int (S::*)() const&>());
+static_assert(
+    !check_three_way_comparable_with<int, int (S::*)() const & noexcept>());
+static_assert(!check_three_way_comparable_with<int, int (S::*)() volatile&>());
+static_assert(
+    !check_three_way_comparable_with<int, int (S::*)() volatile & noexcept>());
+static_assert(
+    !check_three_way_comparable_with<int, int (S::*)() const volatile&>());
+static_assert(!check_three_way_comparable_with<int, int (S::*)() const volatile &
+                                                       noexcept>());
+static_assert(!check_three_way_comparable_with<int, int (S::*)() &&>());
+static_assert(!check_three_way_comparable_with < int,
+              int (S::*)() && noexcept > ());
+static_assert(!check_three_way_comparable_with<int, int (S::*)() const&&>());
+static_assert(!check_three_way_comparable_with < int,
+              int (S::*)() const&& noexcept > ());
+static_assert(!check_three_way_comparable_with<int, int (S::*)() volatile&&>());
+static_assert(!check_three_way_comparable_with < int,
+              int (S::*)() volatile&& noexcept > ());
+static_assert(
+    !check_three_way_comparable_with<int, int (S::*)() const volatile&&>());
+static_assert(!check_three_way_comparable_with < int,
+              int (S::*)() const volatile&& noexcept > ());
+static_assert(!check_three_way_comparable_with<int*, int[5]>());
+static_assert(!check_three_way_comparable_with<int[5], int[5]>());
+static_assert(!check_three_way_comparable_with<std::nullptr_t, int>());
+static_assert(!check_three_way_comparable_with<std::nullptr_t, int*>());
+static_assert(!check_three_way_comparable_with<std::nullptr_t, int[5]>());
+static_assert(!check_three_way_comparable_with<std::nullptr_t, int (*)()>());
+static_assert(!check_three_way_comparable_with<std::nullptr_t, int (&)()>());
+static_assert(!check_three_way_comparable_with<std::nullptr_t, int (S::*)()>());
+static_assert(!check_three_way_comparable_with<void, int>());
+static_assert(!check_three_way_comparable_with<void, int*>());
+static_assert(!check_three_way_comparable_with<void, std::nullptr_t>());
+static_assert(!check_three_way_comparable_with<void, int[5]>());
+static_assert(!check_three_way_comparable_with<void, int (*)()>());
+static_assert(!check_three_way_comparable_with<void, int (&)()>());
+static_assert(!check_three_way_comparable_with<void, int S::*>());
+static_assert(!check_three_way_comparable_with<void, int (S::*)()>());
+}
+
+namespace user_defined {
+struct S {
+    bool operator==(int) const;
+    std::strong_ordering operator<=>(int) const;
+    operator int() const;
+
+    bool operator==(const S&) const = default;
+    auto operator<=>(const S&) const = default;
+};
+
+static_assert(check_three_way_comparable_with<S, int>());
+static_assert(check_three_way_comparable_with<S, int, std::strong_ordering>());
+static_assert(check_three_way_comparable_with<S, int, std::weak_ordering>());
+
+struct SpaceshipNotDeclared {
+};
+
+static_assert(!check_three_way_comparable_with<SpaceshipNotDeclared>());
+
+struct SpaceshipDeleted {
+    auto operator<=>(const SpaceshipDeleted&) const = delete;
+};
+
+static_assert(!check_three_way_comparable_with<SpaceshipDeleted>());
+
+struct SpaceshipWithoutEqualityOperator {
+    auto operator<=>(const SpaceshipWithoutEqualityOperator&) const;
+};
+
+static_assert(!check_three_way_comparable_with<SpaceshipWithoutEqualityOperator>());
+
+struct EqualityOperatorDeleted {
+    bool operator==(const EqualityOperatorDeleted&) const = delete;
+};
+
+static_assert(!check_three_way_comparable_with<EqualityOperatorDeleted>());
+
+struct EqualityOperatorOnly {
+    bool operator==(const EqualityOperatorOnly&) const = default;
+};
+
+static_assert(!check_three_way_comparable_with<EqualityOperatorOnly>());
+
+struct SpaceshipDeclaredEqualityOperatorDeleted {
+    bool operator==(const SpaceshipDeclaredEqualityOperatorDeleted&) const = delete;
+    auto operator<=>(const SpaceshipDeclaredEqualityOperatorDeleted&) const = default;
+};
+
+static_assert(!check_three_way_comparable_with<SpaceshipDeclaredEqualityOperatorDeleted>());
+
+struct AllInequalityOperators {
+    bool operator<(const AllInequalityOperators&) const;
+    bool operator<=(const AllInequalityOperators&) const;
+    bool operator>(const AllInequalityOperators&) const;
+    bool operator>=(const AllInequalityOperators&) const;
+    bool operator!=(const AllInequalityOperators&) const;
+};
+
+static_assert(!check_three_way_comparable_with<AllInequalityOperators>());
+
+struct AllComparisonOperators {
+    bool operator<(const AllComparisonOperators&) const;
+    bool operator<=(const AllComparisonOperators&) const;
+    bool operator>(const AllComparisonOperators&) const;
+    bool operator>=(const AllComparisonOperators&) const;
+    bool operator!=(const AllComparisonOperators&) const;
+    bool operator==(const AllComparisonOperators&) const;
+};
+
+static_assert(!check_three_way_comparable_with<AllComparisonOperators>());
+
+struct AllButOneInequalityOperators {
+    bool operator<(const AllButOneInequalityOperators&) const;
+    bool operator<=(const AllButOneInequalityOperators&) const;
+    bool operator>(const AllButOneInequalityOperators&) const;
+    bool operator!=(const AllButOneInequalityOperators&) const;
+};
+
+static_assert(!check_three_way_comparable_with<AllButOneInequalityOperators>());
+
+struct AllInequalityOperatorsOneDeleted {
+    bool operator<(const AllInequalityOperatorsOneDeleted&) const;
+    bool operator<=(const AllInequalityOperatorsOneDeleted&) const;
+    bool operator>(const AllInequalityOperatorsOneDeleted&) const;
+    bool operator>=(const AllInequalityOperatorsOneDeleted&) const = delete;
+    bool operator!=(const AllInequalityOperatorsOneDeleted&) const;
+};
+
+static_assert(!check_three_way_comparable_with<AllInequalityOperatorsOneDeleted>());
+
+struct EqualityOperatorWrongReturnType {
+    int operator==(const EqualityOperatorWrongReturnType&);
+    auto operator<=>(const EqualityOperatorWrongReturnType&) const = default;
+};
+
+static_assert(!check_three_way_comparable_with<EqualityOperatorWrongReturnType>());
+
+struct SpaceshipWrongReturnType {
+    bool operator==(const SpaceshipWrongReturnType&) const = default;
+    int operator<=>(const SpaceshipWrongReturnType&);
+};
+
+static_assert(!check_three_way_comparable_with<SpaceshipWrongReturnType>());
+
+struct EqualityOperatorNonConstArgument {
+    bool operator==(EqualityOperatorNonConstArgument&);
+    auto operator<=>(const EqualityOperatorNonConstArgument&) const = default;
+};
+
+static_assert(!check_three_way_comparable_with<EqualityOperatorNonConstArgument>());
+
+struct SpaceshipNonConstArgument {
+    bool operator==(const SpaceshipNonConstArgument&) const = default;
+    auto operator<=>(SpaceshipNonConstArgument&);
+};
+
+static_assert(!check_three_way_comparable_with<SpaceshipNonConstArgument>());
+}
+
+int main(int, char**) { return 0; }