From 8624d1e32b6766ca64694360bdcfc5b136d35286 Mon Sep 17 00:00:00 2001
From: "A. Jiang" <de34@live.cn>
Date: Mon, 9 Dec 2024 11:49:41 +0800
Subject: [PATCH 1/2] Fix regression with `ranges::to` for ADL-only
 `begin`/`end`

---
 stl/inc/__msvc_ranges_to.hpp                  |  6 ++++-
 .../std/tests/P1206R7_ranges_to_misc/test.cpp | 27 +++++++++++++++++++
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/stl/inc/__msvc_ranges_to.hpp b/stl/inc/__msvc_ranges_to.hpp
index ef3bac4ed67..4eb1e22dc6b 100644
--- a/stl/inc/__msvc_ranges_to.hpp
+++ b/stl/inc/__msvc_ranges_to.hpp
@@ -1121,7 +1121,11 @@ namespace ranges {
                 if constexpr (_Sized_and_reservable<_Rng, _Container>) {
                     _Cont.reserve(static_cast<range_size_t<_Container>>(_RANGES size(_Range)));
                 }
-                for (auto&& _Elem : _Range) {
+
+                auto _Iter = _RANGES begin(_Range);
+                auto _Sent = _RANGES end(_Range);
+                for (; _Iter != _Sent; ++_Iter) {
+                    auto&& _Elem  = *_Iter;
                     using _ElemTy = decltype(_Elem);
                     if constexpr (_Can_emplace_back<_Container, _ElemTy>) {
                         _Cont.emplace_back(_STD forward<_ElemTy>(_Elem));
diff --git a/tests/std/tests/P1206R7_ranges_to_misc/test.cpp b/tests/std/tests/P1206R7_ranges_to_misc/test.cpp
index c788206ffbe..065b8a5dd82 100644
--- a/tests/std/tests/P1206R7_ranges_to_misc/test.cpp
+++ b/tests/std/tests/P1206R7_ranges_to_misc/test.cpp
@@ -336,6 +336,30 @@ constexpr bool test_lwg4016() {
     return true;
 }
 
+struct adl_only_range {
+    static constexpr int numbers[2]{42, 1729};
+
+    void begin() const = delete;
+    void end() const   = delete;
+
+    friend constexpr const int* begin(const adl_only_range&) {
+        return ranges::begin(numbers);
+    }
+    friend constexpr const int* end(const adl_only_range&) {
+        return ranges::end(numbers);
+    }
+};
+
+constexpr bool test_lwg4016_regression() {
+    using vec = restricted_vector<restriction_kind::push_back, int>;
+
+    ranges::contiguous_range auto r = adl_only_range{};
+    auto v                          = r | ranges::to<vec>();
+    assert(ranges::equal(v, adl_only_range::numbers));
+
+    return true;
+}
+
 int main() {
     test_reservable();
     static_assert(test_reservable());
@@ -356,4 +380,7 @@ int main() {
 
     test_lwg4016();
     static_assert(test_lwg4016());
+
+    test_lwg4016_regression();
+    static_assert(test_lwg4016_regression());
 }

From 0363996d424eadc014fe8544df79102e07390826 Mon Sep 17 00:00:00 2001
From: "A. Jiang" <de34@live.cn>
Date: Tue, 10 Dec 2024 19:22:34 +0800
Subject: [PATCH 2/2] Make `_Sent` `const`

Co-authored-by: Hewill Kang <67143766+hewillk@users.noreply.github.com>
---
 stl/inc/__msvc_ranges_to.hpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/stl/inc/__msvc_ranges_to.hpp b/stl/inc/__msvc_ranges_to.hpp
index 4eb1e22dc6b..f13f2026a05 100644
--- a/stl/inc/__msvc_ranges_to.hpp
+++ b/stl/inc/__msvc_ranges_to.hpp
@@ -1122,8 +1122,8 @@ namespace ranges {
                     _Cont.reserve(static_cast<range_size_t<_Container>>(_RANGES size(_Range)));
                 }
 
-                auto _Iter = _RANGES begin(_Range);
-                auto _Sent = _RANGES end(_Range);
+                auto _Iter       = _RANGES begin(_Range);
+                const auto _Sent = _RANGES end(_Range);
                 for (; _Iter != _Sent; ++_Iter) {
                     auto&& _Elem  = *_Iter;
                     using _ElemTy = decltype(_Elem);