diff --git a/include/boost/asio/detail/impl/win_tss_ptr.ipp b/include/boost/asio/detail/impl/win_tss_ptr.ipp
index bd4dc237..abedb473 100644
--- a/include/boost/asio/detail/impl/win_tss_ptr.ipp
+++ b/include/boost/asio/detail/impl/win_tss_ptr.ipp
@@ -31,14 +31,12 @@ namespace detail {
 
 DWORD win_tss_ptr_create()
 {
+  DWORD tss_key = ::TlsAlloc();
 #if defined(UNDER_CE)
-  enum { out_of_indexes = 0xFFFFFFFF };
+  if (tss_key == 0xFFFFFFFF)
 #else
-  enum { out_of_indexes = TLS_OUT_OF_INDEXES };
+  if (tss_key == TLS_OUT_OF_INDEXES)
 #endif
-
-  DWORD tss_key = ::TlsAlloc();
-  if (tss_key == out_of_indexes)
   {
     DWORD last_error = ::GetLastError();
     boost::system::error_code ec(last_error,