diff --git a/libcxx/include/iterator b/libcxx/include/iterator
--- a/libcxx/include/iterator
+++ b/libcxx/include/iterator
@@ -454,25 +454,23 @@
 */
 
 #include <__config>
-#include <iosfwd> // for forward declarations of vector and string.
+#include <__debug>
 #include <__functional_base>
-#include <type_traits>
-#include <compare>
-#include <concepts> // Mandated by the Standard.
-#include <cstddef>
-#include <initializer_list>
 #include <__iterator/concepts.h>
 #include <__iterator/incrementable_traits.h>
 #include <__iterator/iter_move.h>
 #include <__iterator/iterator_traits.h>
 #include <__iterator/readable_traits.h>
-#include <__iterator/concepts.h>
 #include <__memory/addressof.h>
 #include <__memory/pointer_traits.h>
+#include <compare>
+#include <concepts> // Mandated by the Standard.
+#include <cstddef>
+#include <initializer_list>
+#include <iosfwd> // for forward declarations of vector and string
+#include <type_traits>
 #include <version>
 
-#include <__debug>
-
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
@@ -1455,11 +1453,6 @@
     _LIBCPP_CONSTEXPR_IF_NODEBUG friend
     __wrap_iter<_Iter1>
     operator+(typename __wrap_iter<_Iter1>::difference_type, __wrap_iter<_Iter1>) _NOEXCEPT;
-
-    template <class _Ip, class _Op> friend _LIBCPP_CONSTEXPR_AFTER_CXX17 _Op copy(_Ip, _Ip, _Op);
-    template <class _B1, class _B2> friend _LIBCPP_CONSTEXPR_AFTER_CXX17 _B2 copy_backward(_B1, _B1, _B2);
-    template <class _Ip, class _Op> friend _LIBCPP_CONSTEXPR_AFTER_CXX17 _Op move(_Ip, _Ip, _Op);
-    template <class _B1, class _B2> friend _LIBCPP_CONSTEXPR_AFTER_CXX17 _B2 move_backward(_B1, _B1, _B2);
 };
 
 #if _LIBCPP_STD_VER <= 17
diff --git a/libcxx/utils/ci/buildkite-pipeline.yml b/libcxx/utils/ci/buildkite-pipeline.yml
--- a/libcxx/utils/ci/buildkite-pipeline.yml
+++ b/libcxx/utils/ci/buildkite-pipeline.yml
@@ -27,7 +27,7 @@
     artifact_paths:
       - "**/clang-format.patch"
     agents:
-      queue: "libcxx-builders"
+      queue: "service"
     retry:
       automatic:
         - exit_status: -1  # Agent was lost
@@ -40,7 +40,7 @@
     artifact_paths:
       - "**/generated_output.patch"
     agents:
-      queue: "libcxx-builders"
+      queue: "service"
     retry:
       automatic:
         - exit_status: -1  # Agent was lost
diff --git a/libcxx/utils/ci/run-buildbot b/libcxx/utils/ci/run-buildbot
--- a/libcxx/utils/ci/run-buildbot
+++ b/libcxx/utils/ci/run-buildbot
@@ -9,6 +9,7 @@
 
 set -ex
 set -o pipefail
+export LANG=C  # for grep
 
 PROGNAME="$(basename "${0}")"
 
@@ -144,8 +145,15 @@
     python3 libcxx/utils/generate_header_tests.py
     git diff | tee ${BUILD_DIR}/generated_output.patch
     # Check if the diffs are empty, fail otherwise.
+    echo "hello world" > foo.txt
+    echo "héllo world" >> foo.txt
+    echo "GOODBYE" >> foo.txt
+    grep -rn '[^ -~]' foo.txt
+    LANG=C grep -rn '[^ -~]' foo.txt
+    LANG=C.UTF-8 grep -rn '[^ -~]' foo.txt
     ! grep -q '^--- a' ${BUILD_DIR}/generated_output.patch || false
     # Reject patches that introduce non-ASCII characters or hard tabs.
+    # Depends on LANG=C set at the top of this script.
     ! grep -rn '[^ -~]' libcxx/include/ || false
     # Check that no dependency cycles have been introduced.
     python3 libcxx/utils/graph_header_deps.py >/dev/null