diff --git a/src/host/genversion.lua b/src/host/genversion.lua
index 42b5e6fe..5ead4c2b 100644
--- a/src/host/genversion.lua
+++ b/src/host/genversion.lua
@@ -5,9 +5,9 @@
 -- Released under the MIT license. See Copyright Notice in luajit.h
 ----------------------------------------------------------------------------
 
-local FILE_ROLLING_H = "luajit_rolling.h"
-local FILE_RELVER_TXT = "luajit_relver.txt"
-local FILE_LUAJIT_H = "luajit.h"
+local FILE_ROLLING_H = arg[1] or "luajit_rolling.h"
+local FILE_RELVER_TXT = arg[2] or "luajit_relver.txt"
+local FILE_LUAJIT_H = arg[3] or "luajit.h"
 
 local function file_read(file)
   local fp = assert(io.open(file, "rb"), "run from the wrong directory")