[libc++] Remove unused defaulted template arg from __rewrap_range.

[AMP999]

Template argument _Unwrapped is always deduced from the type of _Unwrapped __iter.

[llvmbot]

@llvm/pr-subscribers-libcxx

Changes

Template argument _Unwrapped is always deduced from the type of _Unwrapped __iter.

---

Full diff: https://github.com/llvm/llvm-project/pull/67733.diff

1 Files Affected:

• (modified) libcxx/include/__algorithm/unwrap_range.h (+2-2)

diff --git a/libcxx/include/__algorithm/unwrap_range.h b/libcxx/include/__algorithm/unwrap_range.h
index 2c75c8f49de938e..a1e0989570bdb2d 100644
--- a/libcxx/include/__algorithm/unwrap_range.h
+++ b/libcxx/include/__algorithm/unwrap_range.h
@@ -76,7 +76,7 @@ _LIBCPP_HIDE_FROM_ABI constexpr auto __unwrap_range(_Iter __first, _Sent __last)
 template <
     class _Sent,
     class _Iter,
-    class _Unwrapped = decltype(std::__unwrap_range(std::declval<_Iter>(), std::declval<_Sent>()))>
+    class _Unwrapped>
 _LIBCPP_HIDE_FROM_ABI constexpr _Iter __rewrap_range(_Iter __orig_iter, _Unwrapped __iter) {
   return __unwrap_range_impl<_Iter, _Sent>::__rewrap(std::move(__orig_iter), std::move(__iter));
 }
@@ -86,7 +86,7 @@ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR pair<_Unwrapped, _Unwrapped> __unwrap_ra
   return std::make_pair(std::__unwrap_iter(std::move(__first)), std::__unwrap_iter(std::move(__last)));
 }
 
-template <class _Iter, class _Unwrapped = decltype(std::__unwrap_iter(std::declval<_Iter>()))>
+template <class _Iter, class _Unwrapped>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Iter __rewrap_range(_Iter __orig_iter, _Unwrapped __iter) {
   return std::__rewrap_iter(std::move(__orig_iter), std::move(__iter));
 }

[AMP999]

The CI is failing in https://buildkite.com/llvm-project/libcxx-ci/builds/30092#018add7f-bf00-44ec-9959-2a1ac111d99c because the benchmarks already committed to main are trying to use ranges::ends_with in C++20 mode. What should I do about that?
@var-const

[ldionne]

The CI is failing in https://buildkite.com/llvm-project/libcxx-ci/builds/30092#018add7f-bf00-44ec-9959-2a1ac111d99c because the benchmarks already committed to main are trying to use ranges::ends_with in C++20 mode. What should I do about that? @var-const

This should be fixed on main now.

[ldionne]

This makes sense to me, but I'd like @philnik777 to have a quick look as well to make sure this was a copy-paste error (what it looks like).

@philnik777 Did you write it that way to make it possible to deduce from something like {} passed as an argument?

@AMP999 Please wait for @philnik777 to validate before merging.

[philnik777]

I think my initial intent was to ensure that we only take the unwrapped iterator. Basically, the argument should have been type_identity_t<_Unwrapped>. Given that this is already enforced by __unwrap_iter_impl, i don't think there is anything wrong with just removing the default (especially given that it's broken already).

LGTM with a clang-format run. (The file is formatted % the changed lines and a whitespace change above)

[AMP999]

@philnik777 The CI is green with respect to clang-format. Can you help me land this? Amirreza Ashouri <ar.ashouri999@gmail.com>

[philnik777]

You have to remove libcxx/include/__algorithm/unwrap_range.h from libcxx/utils/data/ignore_format.txt to check formatting.

[AMP999]

You have to remove libcxx/include/__algorithm/unwrap_range.h from libcxx/utils/data/ignore_format.txt to check formatting.

Thank you! I've fixed that.