diff --git a/include/llfio/v2.0/map_handle.hpp b/include/llfio/v2.0/map_handle.hpp
index 55cefa8f..3962be16 100644
--- a/include/llfio/v2.0/map_handle.hpp
+++ b/include/llfio/v2.0/map_handle.hpp
@@ -294,8 +294,8 @@ support this operation). You may find the `is_nvram()` observer of particular us
 */
 inline io_handle::const_buffer_type nvram_barrier(io_handle::const_buffer_type req, bool evict = false) noexcept
 {
-  auto *tp = (io_handle::const_buffer_type::pointer)(((uintptr_t) req.data()) & ~63);
-  io_handle::const_buffer_type ret{tp, (size_t)(req.data() + 63 + req.size() - tp) & ~63};
+  auto *tp = (io_handle::const_buffer_type::pointer) (((uintptr_t) req.data()) & ~63);
+  io_handle::const_buffer_type ret{tp, (size_t) (req.data() + 63 + req.size() - tp) & ~63};
   if(memory_flush_none == mem_flush_stores(ret.data(), ret.size(), evict ? memory_flush_evict : memory_flush_retain))
   {
     ret = {tp, 0};
@@ -954,7 +954,8 @@ namespace detail
   {
     try
     {
-      auto make_shared = [](map_handle h) {
+      auto make_shared = [](map_handle h) -> io_handle::registered_buffer_type
+      {
         struct registered_buffer_type_indirect : io_multiplexer::_registered_buffer_type
         {
           map_handle h;
@@ -964,8 +965,7 @@ namespace detail
           {
           }
         };
-        auto ptr = std::make_shared<registered_buffer_type_indirect>(std::move(h));
-        return ptr;
+        return io_handle::registered_buffer_type(std::make_shared<registered_buffer_type_indirect>(std::move(h)));
       };
       const auto &page_sizes = utils::page_sizes(true);
       size_t idx = 0;