diff --git a/include/boost/detail/lightweight_test.hpp b/include/boost/detail/lightweight_test.hpp
index 33f5234..8fd04a5 100644
--- a/include/boost/detail/lightweight_test.hpp
+++ b/include/boost/detail/lightweight_test.hpp
@@ -1,6 +1,8 @@
 #ifndef BOOST_DETAIL_LIGHTWEIGHT_TEST_HPP_INCLUDED
 #define BOOST_DETAIL_LIGHTWEIGHT_TEST_HPP_INCLUDED
 
+// MS compatible compilers support #pragma once
+
 #if defined(_MSC_VER) && (_MSC_VER >= 1020)
 # pragma once
 #endif
diff --git a/include/boost/detail/quick_allocator.hpp b/include/boost/detail/quick_allocator.hpp
index 83987d5..e2b3f57 100644
--- a/include/boost/detail/quick_allocator.hpp
+++ b/include/boost/detail/quick_allocator.hpp
@@ -1,6 +1,8 @@
 #ifndef BOOST_DETAIL_QUICK_ALLOCATOR_HPP_INCLUDED
 #define BOOST_DETAIL_QUICK_ALLOCATOR_HPP_INCLUDED
 
+// MS compatible compilers support #pragma once
+
 #if defined(_MSC_VER) && (_MSC_VER >= 1020)
 # pragma once
 #endif