diff --git a/src/win32/thread.cpp b/src/win32/thread.cpp
index cc7b85a2..972b7310 100644
--- a/src/win32/thread.cpp
+++ b/src/win32/thread.cpp
@@ -527,8 +527,9 @@ namespace boost
 
     unsigned thread::physical_concurrency() BOOST_NOEXCEPT
     {
+      // a bit too strict: Windows XP with SP3 would be sufficient
 #if BOOST_PLAT_WINDOWS_RUNTIME                                    \
-    || ( BOOST_USE_WINAPI_VERSION <= BOOST_WINAPI_VERSION_WINXP ) \  // a bit too strict: Windows XP with SP3 would be sufficient
+    || ( BOOST_USE_WINAPI_VERSION <= BOOST_WINAPI_VERSION_WINXP ) \
     || ( ( defined(__MINGW32__) && !defined(__MINGW64__) ) && _WIN32_WINNT < 0x0600)
         return 0;
 #else