From 2ef056c43e37b0a00047d4fc8ac57db789622392 Mon Sep 17 00:00:00 2001
From: Yong Gyu Lee <cosgenio@gmail.com>
Date: Mon, 26 Aug 2024 20:57:53 +0900
Subject: [PATCH] Fix dumb MSVC bug

---
 README.md                             | 1 +
 include/preview/__memory/to_address.h | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/README.md b/README.md
index f0e271a..4f7547c 100644
--- a/README.md
+++ b/README.md
@@ -820,6 +820,7 @@ Description
 * Notes
   * `to_address`
     * If `std::pointer_traits::to_address` is available, it is used before `preview::pointer_traits::to_address`.
+      * ⚠️ `std::pointer_traits::to_address` is not sfinae-friendly until MSVC 2022, so not used.
 
 #### `<memory_resource>`
   N/A
diff --git a/include/preview/__memory/to_address.h b/include/preview/__memory/to_address.h
index f1a31c1..23f09e6 100644
--- a/include/preview/__memory/to_address.h
+++ b/include/preview/__memory/to_address.h
@@ -24,8 +24,12 @@ struct has_to_address<T, Traits, void_t<decltype(Traits<T>::to_address(std::decl
 
 template<typename T>
 using to_address_tag = conditional_tag<
+#if defined(_MSC_VER) && _MSC_VER < 1930 // std::pointer_traits is not sfinae-friendly before VS 2022
+    has_to_address<T, pointer_traits>
+#else
     has_to_address<T, std::pointer_traits>,
     has_to_address<T, pointer_traits>
+#endif
 >;
 
 template<typename T>