diff --git a/common/luaclass.c b/common/luaclass.c
index 505c1956..6866a3d7 100644
--- a/common/luaclass.c
+++ b/common/luaclass.c
@@ -131,7 +131,7 @@ luaA_openlib(lua_State *L, const char *name,
     lua_pushvalue(L, -1);           /* dup metatable                      2 */
     lua_setfield(L, -2, "__index"); /* metatable.__index = metatable      1 */
 
-    luaA_registerlib(L, NULL, meta);                                   /* 1 */
+    luaA_setfuncs(L, meta);                                            /* 1 */
     luaA_registerlib(L, name, methods);                                /* 2 */
     lua_pushvalue(L, -1);           /* dup self as metatable              3 */
     lua_setmetatable(L, -2);        /* set self as metatable              2 */
@@ -267,7 +267,7 @@ luaA_class_setup(lua_State *L, lua_class_t *class,
 
     lua_setfield(L, -2, "__index"); /* metatable.__index = metatable      1 */
 
-    luaA_registerlib(L, NULL, meta);                                   /* 1 */
+    luaA_setfuncs(L, meta);                                            /* 1 */
     luaA_registerlib(L, name, methods);                                /* 2 */
     lua_pushvalue(L, -1);           /* dup self as metatable              3 */
     lua_setmetatable(L, -2);        /* set self as metatable              2 */
diff --git a/luaa.h b/luaa.h
index 6f6f34f1..e1592583 100644
--- a/luaa.h
+++ b/luaa.h
@@ -128,21 +128,27 @@ luaA_rawlen(lua_State *L, int idx)
 static inline void
 luaA_registerlib(lua_State *L, const char *libname, const luaL_Reg *l)
 {
+    assert(libname);
 #if LUA_VERSION_NUM >= 502
-    if (libname)
-    {
-        lua_newtable(L);
-        luaL_setfuncs(L, l, 0);
-        lua_pushvalue(L, -1);
-        lua_setglobal(L, libname);
-    }
-    else
-        luaL_setfuncs(L, l, 0);
+    lua_newtable(L);
+    luaL_setfuncs(L, l, 0);
+    lua_pushvalue(L, -1);
+    lua_setglobal(L, libname);
 #else
     luaL_register(L, libname, l);
 #endif
 }
 
+static inline void
+luaA_setfuncs(lua_State *L, const luaL_Reg *l)
+{
+#if LUA_VERSION_NUM >= 502
+    luaL_setfuncs(L, l, 0);
+#else
+    luaL_register(L, NULL, l);
+#endif
+}
+
 static inline bool
 luaA_checkboolean(lua_State *L, int n)
 {