Re: userdata and the gc

[David Given <dg@...>]

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Adrian Sietsma wrote:
[...]
> consider - if a userdata can move due to garbage collection, it would
> have _major_ implications for c routines. There would need to be clear
> rules on the lifetime of pointers returned from lua_newuserdata() and
> lua_touserdata(), and which operations may invalidate them. Or, some
> contract with the gc to say "leave this block alone".

I'd just assumed that the same rules as for strings applied --- i.e.,
that the pointer was valid only while it was on the Lua stack. As soon
as you remove it from the stack, the pointer becomes invalid.

- --
+- David Given --McQ-+
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