Index: generic/fakesql.h
==================================================================
--- generic/fakesql.h
+++ generic/fakesql.h
@@ -67,11 +67,11 @@
 typedef SQLSMALLINT SQLRETURN;
 
 /* TODO - Check how the SQLLEN and SQLULEN types are handled on
  *        64-bit Unix. */
 
-#if defined(__WIN64)
+#if defined(_WIN64)
 typedef Tcl_WideInt SQLLEN;
 typedef Tcl_WideUInt SQLULEN;
 #else
 typedef SQLINTEGER SQLLEN;
 typedef SQLUINTEGER SQLULEN;