[libc++] LWG4012: common_view::begin/end are missing the simple-view check

[changkhothuychung]

close #105320

[llvmbot]

@llvm/pr-subscribers-libcxx

Author: Nhat Nguyen (changkhothuychung)

Changes

close #105320

---

Full diff: https://github.com/llvm/llvm-project/pull/153674.diff

1 Files Affected:

• (modified) libcxx/include/__ranges/common_view.h (+2-2)

diff --git a/libcxx/include/__ranges/common_view.h b/libcxx/include/__ranges/common_view.h
index 133236dd1d78a..ff26a78c00052 100644
--- a/libcxx/include/__ranges/common_view.h
+++ b/libcxx/include/__ranges/common_view.h
@@ -58,7 +58,7 @@ class common_view : public view_interface<common_view<_View>> {
 
   _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
 
-  _LIBCPP_HIDE_FROM_ABI constexpr auto begin() {
+  _LIBCPP_HIDE_FROM_ABI constexpr auto begin() requires (!__simple_view<_View>) {
     if constexpr (random_access_range<_View> && sized_range<_View>)
       return ranges::begin(__base_);
     else
@@ -74,7 +74,7 @@ class common_view : public view_interface<common_view<_View>> {
       return common_iterator<iterator_t<const _View>, sentinel_t<const _View>>(ranges::begin(__base_));
   }
 
-  _LIBCPP_HIDE_FROM_ABI constexpr auto end() {
+  _LIBCPP_HIDE_FROM_ABI constexpr auto end() requires (!__simple_view<_View>) {
     if constexpr (random_access_range<_View> && sized_range<_View>)
       return ranges::begin(__base_) + ranges::size(__base_);
     else

[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.

[Zingam]

Please add a SFINAE test.

[changkhothuychung]

@H-G-Hristov reminder ping, looks like the CI fails are unrelated.

[H-G-Hristov]

@H-G-Hristov reminder ping, looks like the CI fails are unrelated.

Please wait for a libc++ maintainer to approve before merging.

[changkhothuychung]

@frederick-vs-ja Hi! is there any chance you can review this ?

[frederick-vs-ja]

I think this is fine. Let's update the branch (merge or rebase) and wait for CI passing.

[frederick-vs-ja]

Oops, I overlooked a missing piece.

We should also change this line in the documentation.

llvm-project/libcxx/docs/Status/Cxx2cIssues.csv

Line 49 in 4120496

"`LWG4012 <https://wg21.link/LWG4012>`__","``common_view::begin/end`` are missing the ``simple-view`` check","2024-03 (Tokyo)","","","`#105320 <https://github.com/llvm/llvm-project/issues/105320>`__",""

-"`LWG4012 <https://wg21.link/LWG4012>`__","``common_view::begin/end`` are missing the ``simple-view`` check","2024-03 (Tokyo)","","","`#105320 <https://github.com/llvm/llvm-project/issues/105320>`__",""
+"`LWG4012 <https://wg21.link/LWG4012>`__","``common_view::begin/end`` are missing the ``simple-view`` check","2024-03 (Tokyo)","|Complete|","22","`#105320 <https://github.com/llvm/llvm-project/issues/105320>`__",""