diff --git a/luaconf.h b/luaconf.h
index b883910d..76ef88f5 100644
--- a/luaconf.h
+++ b/luaconf.h
@@ -1,5 +1,5 @@
 /*
-** $Id: luaconf.h,v 1.244 2015/02/05 16:53:34 roberto Exp roberto $
+** $Id: luaconf.h,v 1.245 2015/02/05 17:15:33 roberto Exp roberto $
 ** Configuration file for Lua
 ** See Copyright Notice in lua.h
 */
@@ -300,20 +300,15 @@
 */
 #define LUA_COMPAT_APIINTCASTS
 
-
-/*
-@@ LUA_COMPAT_FLOATSTRING makes Lua format integral floats without a
-@@ a float mark ('.0').
-** This macro is not on by default even in compatibility mode,
-** because this is not really an incompatibility.
-*/
-/* #define LUA_COMPAT_FLOATSTRING */
-
 #endif				/* } */
 
 
 #if defined(LUA_COMPAT_5_1)	/* { */
 
+/* Incompatibilities from 5.2 -> 5.3 */
+#define LUA_COMPAT_MATHLIB
+#define LUA_COMPAT_APIINTCASTS
+
 /*
 @@ LUA_COMPAT_UNPACK controls the presence of global 'unpack'.
 ** You can replace it with 'table.unpack'.
@@ -373,6 +368,15 @@
 
 #endif				/* } */
 
+
+/*
+@@ LUA_COMPAT_FLOATSTRING makes Lua format integral floats without a
+@@ a float mark ('.0').
+** This macro is not on by default even in compatibility mode,
+** because this is not really an incompatibility.
+*/
+/* #define LUA_COMPAT_FLOATSTRING */
+
 /* }================================================================== */