Re: Why GCTM stop gc step before calling userdata's finalizer?

[书呆彭, Peng Yi <nerditation@...>]

在 2016/1/9 20:35, 张伟智 写道:
> Lua version is 5.2.4.
> In lgc.c line 820, function GCTM,
> g->gcrunning is set to 0 to avoid GC steps,
> I think if g->gcrunning remains unchanged,
> line 824 luaD_pcall will trigger luaC_step->luaC_forcestep->GCTM during executing __gc finalizer.
> But what is the problem if recursive enter GCTM ?

In my understanding, the Lua VM is reentrant, but the finalizers are meant to be called
in sequence. according to Lua's semantic, the finalizers are called in the reverse order
that the objects were marked for for finalization. so the finalizer for the next object
must be called _after_ the current object's finished its execution.

--
the nerdy Peng / 书呆彭 / Sent from Thunderbird