From 619e8f46f3c77cb97464cf64e01872e6246f8875 Mon Sep 17 00:00:00 2001
From: Adrian Vogelsgesang <avogelsgesang@salesforce.com>
Date: Sat, 6 Aug 2022 15:09:50 +0200
Subject: [PATCH] [libc++] Remove `operator!=` from `type_info` in C++20

Implements part of:

* P1614R2 The Mothership has Landed

Reviewed By: #libc, Mordante

Differential Revision: https://reviews.llvm.org/D130853
---
 libcxx/docs/Status/SpaceshipProjects.csv | 1 +
 libcxx/include/typeinfo                  | 6 +++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/libcxx/docs/Status/SpaceshipProjects.csv b/libcxx/docs/Status/SpaceshipProjects.csv
index 87e0c60..ecf0431 100644
--- a/libcxx/docs/Status/SpaceshipProjects.csv
+++ b/libcxx/docs/Status/SpaceshipProjects.csv
@@ -12,6 +12,7 @@ Section,Description,Dependencies,Assignee,Complete
 | `weak_order_fallback <https://reviews.llvm.org/D111514>`_
 | `partial_order_fallback <https://reviews.llvm.org/D111514>`_",None,Arthur O'Dwyer,|Complete| [#note-strongorder]_
 | `[alg.three.way] <https://wg21.link/alg.three.way>`_,| `lexicographical_compare_three_way <https://reviews.llvm.org/D80902>`_,[comparisons.three.way],Christopher Di Bella,|In Progress|
+| `[type.info] <https://wg21.link/type.info>`_,| `typeinfo <https://reviews.llvm.org/D130853>`_,None,Adrian Vogelsgesang,|Complete|
 | `[coroutine.handle.compare] <https://wg21.link/coroutine.handle.compare>`_,| `coroutine_handle <https://reviews.llvm.org/D109433>`_,[comparisons.three.way],Chuanqi Xu,|Complete|
 | `[pairs.spec] <https://wg21.link/pairs.spec>`_,| `pair <https://reviews.llvm.org/D107721>`_,[expos.only.func],Kent Ross,|Complete|
 | `[syserr.errcat.nonvirtuals] <https://wg21.link/syserr.errcat.nonvirtuals>`_,| error_category,[comparisons.three.way],Unassigned,|Not Started|
diff --git a/libcxx/include/typeinfo b/libcxx/include/typeinfo
index 1f31608..d81a3099 100644
--- a/libcxx/include/typeinfo
+++ b/libcxx/include/typeinfo
@@ -22,7 +22,7 @@ public:
     virtual ~type_info();
 
     bool operator==(const type_info& rhs) const noexcept;
-    bool operator!=(const type_info& rhs) const noexcept;
+    bool operator!=(const type_info& rhs) const noexcept; // removed in C++20
 
     bool before(const type_info& rhs) const noexcept;
     size_t hash_code() const noexcept;
@@ -112,9 +112,11 @@ public:
       return __compare(__arg) == 0;
     }
 
+#if _LIBCPP_STD_VER <= 17
     _LIBCPP_INLINE_VISIBILITY
     bool operator!=(const type_info& __arg) const _NOEXCEPT
     { return !operator==(__arg); }
+#endif
 };
 
 #else // !defined(_LIBCPP_ABI_MICROSOFT)
@@ -337,9 +339,11 @@ public:
       return __impl::__eq(__type_name, __arg.__type_name);
     }
 
+#if _LIBCPP_STD_VER <= 17
     _LIBCPP_INLINE_VISIBILITY
     bool operator!=(const type_info& __arg) const _NOEXCEPT
     { return !operator==(__arg); }
+#endif
 };
 #endif // defined(_LIBCPP_ABI_MICROSOFT)
 
-- 
2.7.4