LUAI_EXTRASPACE    27 lib/lua/lstate.c #define state_size(x)	(sizeof(x) + LUAI_EXTRASPACE)
LUAI_EXTRASPACE    28 lib/lua/lstate.c #define fromstate(l)	(cast(lu_byte *, (l)) - LUAI_EXTRASPACE)
LUAI_EXTRASPACE    29 lib/lua/lstate.c #define tostate(l)   (cast(lua_State *, cast(lu_byte *, l) + LUAI_EXTRASPACE))