[libc++][ranges] Fix `iota_view`'s constructor's incorrect constraint

One of the overload of the constructors should check Bound is not unreachable_sentinel_t, instead of the Start

Differential Revision: https://reviews.llvm.org/D150206

2 files changed, 7 insertions, 1 deletions

diff --git a/libcxx/include/__ranges/iota_view.h b/libcxx/include/__ranges/iota_view.h
index 52e8e822f566..ebfa0220070a 100644
--- a/libcxx/include/__ranges/iota_view.h
+++ b/libcxx/include/__ranges/iota_view.h
@@ -336,7 +336,7 @@ namespace ranges {
 
     _LIBCPP_HIDE_FROM_ABI
     constexpr _LIBCPP_EXPLICIT_SINCE_CXX23 iota_view(__iterator __first, __sentinel __last)
-      requires(!same_as<_Start, _BoundSentinel> && !same_as<_Start, unreachable_sentinel_t>)
+      requires(!same_as<_Start, _BoundSentinel> && !same_as<_BoundSentinel, unreachable_sentinel_t>)
     : iota_view(std::move(__first.__value_), std::move(__last.__bound_sentinel_)) {}
 
     _LIBCPP_HIDE_FROM_ABI
diff --git a/libcxx/test/std/ranges/range.factories/range.iota.view/ctor.first.last.pass.cpp b/libcxx/test/std/ranges/range.factories/range.iota.view/ctor.first.last.pass.cpp
index ee0e7fceffa6..67b7dc428a14 100644
--- a/libcxx/test/std/ranges/range.factories/range.iota.view/ctor.first.last.pass.cpp
+++ b/libcxx/test/std/ranges/range.factories/range.iota.view/ctor.first.last.pass.cpp
@@ -76,6 +76,12 @@ constexpr bool test() {
     assert(std::ranges::next(io.begin(), 10) == io.end());
   }
 
+  {
+    std::ranges::iota_view<int, std::unreachable_sentinel_t> iv1;
+    // There should be only one overload available and {} resolves to unreachable_sentinel_t
+    [[maybe_unused]] std::ranges::iota_view<int, std::unreachable_sentinel_t> iv2(iv1.begin(), {});
+  }
+
   return true;
 }