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From: Chong Yidong <cyd@stupidchicken.com>
Newsgroups: gmane.emacs.devel
Subject: Re: Copying one Lisp_Object to another in C code?
Date: Thu, 01 Jul 2010 21:42:54 -0400
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To: James Cloos <cloos@jhcloos.com>
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James Cloos <cloos@jhcloos.com> writes:

> Given:
>
>     static void (foo)
>         Lisp_Object foo;
>     {
>         Lisp_Object bar;
>     /* etc */
>
> is it OK to do:
>
>         bar = foo;

Yes.

> I presume GCPRO1 (foo) is in order either way?

Only if the code ends up calling eval, and for the benefit of the
platforms that don't use stack marking.