Fix build on Windows in C++26 mode

Author: Zingam

libcxx/include/fstream

@@ -218,7 +218,7 @@ _LIBCPP_PUSH_MACROS
 _LIBCPP_BEGIN_NAMESPACE_STD
 
 #  if _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_WIN32API)
-_LIBCPP_EXPORTED_FROM_ABI void* __filebuf_windows_native_handle(FILE* __file);
+_LIBCPP_EXPORTED_FROM_ABI void* __filebuf_windows_native_handle(FILE* __file) noexcept;
 #  endif
 
 template <class _CharT, class _Traits>

libcxx/test/std/input.output/file.streams/fstreams/filebuf.members/native_handle.assert.pass.cpp

@@ -20,7 +20,7 @@
 
 #include <fstream>
 
-#include "../native_handle_test_helpers.h"
+#include "../native_handle_assert_test_helpers.h"
 
 int main(int, char**) {
   test_native_handle_assertion<std::basic_filebuf<char>>();

libcxx/test/std/input.output/file.streams/fstreams/fstream.members/native_handle.assert.pass.cpp

@@ -20,7 +20,7 @@
 
 #include <fstream>
 
-#include "../native_handle_test_helpers.h"
+#include "../native_handle_assert_test_helpers.h"
 
 int main(int, char**) {
   test_native_handle_assertion<std::basic_fstream<char>>();

libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/native_handle.assert.pass.cpp

@@ -20,7 +20,7 @@
 
 #include <fstream>
 
-#include "../native_handle_test_helpers.h"
+#include "../native_handle_assert_test_helpers.h"
 
 int main(int, char**) {
   test_native_handle_assertion<std::basic_ifstream<char>>();

libcxx/test/std/input.output/file.streams/fstreams/native_handle_assert_test_helpers.h

@@ -0,0 +1,28 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef TEST_STD_INPUT_OUTPUT_FILE_STREAMS_FSTREAMS_ASSERT_TEST_HELPERS_H
+#define TEST_STD_INPUT_OUTPUT_FILE_STREAMS_FSTREAMS_ASSERT_TEST_HELPERS_H
+
+#if !__has_include(<unistd.h>) || !__has_include(<sys/wait.h>)
+#  error "Requires UNIX headers"
+#endif
+
+#include "check_assertion.h"
+
+template <typename StreamT>
+inline void test_native_handle_assertion() {
+  StreamT f;
+
+  // non-const
+  TEST_LIBCPP_ASSERT_FAILURE(f.native_handle(), "File must be opened");
+  // const
+  TEST_LIBCPP_ASSERT_FAILURE(std::as_const(f).native_handle(), "File must be opened");
+}
+
+#endif // TEST_STD_INPUT_OUTPUT_FILE_STREAMS_FSTREAMS_ASSERT_TEST_HELPERS_H

libcxx/test/std/input.output/file.streams/fstreams/native_handle_test_helpers.h

@@ -25,17 +25,14 @@
 #endif
 
 #include "platform_support.h"
-#include "test_macros.h"
 #include "types.h"
 
 #if TEST_STD_VER >= 26
 
-#  include "check_assertion.h"
-
 inline bool is_handle_valid(NativeHandleT handle) {
 #  if defined(_WIN32)
   BY_HANDLE_FILE_INFORMATION fileInformation;
-  return GetFileInformationByHandle(handle, &fileInformation));
+  return GetFileInformationByHandle(handle, &fileInformation);
 #  elif __has_include(<unistd.h>) // POSIX
   return fcntl(handle, F_GETFL) != -1 || errno != EBADF;
 #  else
@@ -75,16 +72,6 @@ inline void test_native_handle() {
   }
 }
 
-template <typename StreamT>
-inline void test_native_handle_assertion() {
-  StreamT f;
-
-  // non-const
-  TEST_LIBCPP_ASSERT_FAILURE(f.native_handle(), "File must be opened");
-  // const
-  TEST_LIBCPP_ASSERT_FAILURE(std::as_const(f).native_handle(), "File must be opened");
-}
-
 template <typename StreamT>
 inline void test_native_handle_type() {
   static_assert(std::is_trivially_copyable_v<typename StreamT::native_handle_type>);

libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/native_handle.assert.pass.cpp

@@ -20,7 +20,7 @@
 
 #include <fstream>
 
-#include "../native_handle_test_helpers.h"
+#include "../native_handle_assert_test_helpers.h"
 
 int main(int, char**) {
   test_native_handle_assertion<std::basic_ofstream<char>>();