diff --git a/include/mio/detail/basic_mmap.hpp b/include/mio/detail/basic_mmap.hpp
index 512d537..c4be177 100644
--- a/include/mio/detail/basic_mmap.hpp
+++ b/include/mio/detail/basic_mmap.hpp
@@ -73,6 +73,12 @@ private:
     // Points to the first requested byte, and not to the actual start of the mapping.
     pointer data_ = nullptr;
 
+    // Length, in bytes, requested by user, which may not be the length of the full
+    // mapping, and the entire length of the full mapping.
+    size_type length_ = 0;
+    size_type mapped_length_ = 0;
+
+    // Letting user map a file using both an existing file handle and a path introcudes
     // On POSIX, we only need a file handle to create a mapping, while on Windows
     // systems the file handle is necessary to retrieve a file mapping handle, but any
     // subsequent operations on the mapped region must be done through the latter.
@@ -81,12 +87,6 @@ private:
     handle_type file_mapping_handle_ = INVALID_HANDLE_VALUE;
 #endif
 
-    // Length, in bytes, requested by user, which may not be the length of the full
-    // mapping, and the entire length of the full mapping.
-    size_type length_ = 0;
-    size_type mapped_length_ = 0;
-
-    // Letting user map a file using both an existing file handle and a path introcudes
     // some complexity in that we must not close the file handle if user provided it,
     // but we must close it if we obtained it using the provided path. For this reason,
     // this flag is used to determine when to close file_handle_.