diff --git a/lprefix.h b/lprefix.h
index f401c9c..f209cea 100644
--- a/lprefix.h
+++ b/lprefix.h
@@ -242,13 +242,17 @@ static void createmeta (lua_State *L);
 #  undef LUA_FILEHANDLE
 #  define LUA_FILEHANDLE COMPAT53_LUA_PFILEHANDLE
 
+LUAMOD_API int luaopen_compat53_io (lua_State *L) {
+  luaL_Reg const funcs[] = {
+
 /* for PUC-Rio Lua 5.1 only */
 #  if defined(LUA_VERSION_NUM) && LUA_VERSION_NUM == 501 && !defined(LUA_JITLIBNAME)
 
-LUAMOD_API int luaopen_compat53_io (lua_State *L) {
-  luaL_Reg const funcs[] = {
     { "popen", io_popen },
     { "type", io_ptype },
+
+#  endif /* for PUC-Rio Lua 5.1 only */
+
     { NULL, NULL }
   };
   luaL_newlib(L, funcs);
@@ -256,7 +260,6 @@ LUAMOD_API int luaopen_compat53_io (lua_State *L) {
   return 1;
 }
 
-#  endif /* for PUC-Rio Lua 5.1 only */
 
 /* fake CLANG feature detection on other compilers */
 #  ifndef __has_attribute