[LIBCXX] std::ostream::sentry should be exported

for testing by CI.
std::istream::sentry is left original to ensure test detects this defect.

Author: kikairoya

libcxx/include/__ostream/basic_ostream.h

@@ -665,8 +665,12 @@ basic_ostream<char, _Traits>& operator<<(basic_ostream<char, _Traits>&, const ch
 
 #  endif // _LIBCPP_STD_VER >= 20
 
+extern template _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostream<char>::sentry::sentry(basic_ostream<char>& __os);
+extern template _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostream<char>::sentry::~sentry();
 extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostream<char>;
 #  if _LIBCPP_HAS_WIDE_CHARACTERS
+extern template _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostream<wchar_t>::sentry::sentry(basic_ostream<wchar_t>& __os);
+extern template _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostream<wchar_t>::sentry::~sentry();
 extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostream<wchar_t>;
 #  endif
 

libcxx/src/ios.instantiations.cpp

@@ -20,13 +20,21 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 template class _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS basic_ios<char>;
 template class _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS basic_streambuf<char>;
 template class _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS basic_istream<char>;
+#ifdef _MSC_VER
+template _LIBCPP_EXPORTED_FROM_ABI basic_ostream<char>::sentry::sentry(basic_ostream<char>& __os);
+template _LIBCPP_EXPORTED_FROM_ABI basic_ostream<char>::sentry::~sentry();
+#endif
 template class _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS basic_ostream<char>;
 template class _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS basic_iostream<char>;
 
 #if _LIBCPP_HAS_WIDE_CHARACTERS
 template class _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS basic_ios<wchar_t>;
 template class _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS basic_streambuf<wchar_t>;
 template class _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS basic_istream<wchar_t>;
+#ifdef _MSC_VER
+template _LIBCPP_EXPORTED_FROM_ABI basic_ostream<wchar_t>::sentry::sentry(basic_ostream<wchar_t>& __os);
+template _LIBCPP_EXPORTED_FROM_ABI basic_ostream<wchar_t>::sentry::~sentry();
+#endif
 template class _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS basic_ostream<wchar_t>;
 #endif