diff --git a/variables.cmake b/variables.cmake
index 7e683a7..22d410a 100644
--- a/variables.cmake
+++ b/variables.cmake
@@ -75,6 +75,8 @@ if (WIN32)
         set(build_win64 1)
         set(build_winstore 1)
         set(build_winstore64 1)
+    elseif (CMAKE_SIZEOF_VOID_P EQUAL 8)
+        set(build_win64 1)
     endif()
 elseif (APPLE)
     if (DESKTOP_APP_SPECIAL_TARGET STREQUAL "osx")