Subj : Re: Garbage Collection Woes
To   : netscape.public.mozilla.jseng
From : "Stephen Jones" <Stephen@Jones-net.com>
Date : Mon Apr 28 2003 10:35 am

One more piece of information . . . this only seems to happen to objects
created in contexts other than the global context  . . . am I doing
something wrong when executing GC? This is the code I am using . . .

 while( ( theCurrentContext = JS_ContextIterator( m_JSRunTimePtr,
&theContextIterator ) ) != NULL )
 {
    JS_GC( theCurrentContext );
 }

Is the "live-thing" graph different for different contexts?

Thanks,
- S


"Stephen Jones" <Stephen@Jones-net.com> wrote in message
news:b8bugv$aen1@ripley.netscape.com...
> I thought I had Garbage Collection in SpiderMonkey figured out, but it
turns
> out I was wrong and I can't figure it out to save my life. I've read all
the
> old posts to this newsgroup regarding Garbage Collection, all the GC tips
on
> the web I can find and it seems to make sense, but it doesn't work and I
> can't figure out what I'm doing wrong.
>
> I was just using JS_AddNamedRoot for everything, but it turns out that
> doesn't work for (probably) obvious reasons. If you have multiple objects
> that are using the same object and one goes out of scope and removes the
> root, then that object is unprotected.
>
> From what I understand, basically, you are supposed to protect object
froms
> GC by setting them as properties on other protected objects. Please
correct
> me if I'm wrong.
>
> So, I have a root object that I "attach" to the global object using
> JS_DefineProperty (I assume that this protects this object, I can't tell
> because I have AddRoots everywhere . . . I'm trying to understand this so
I
> can clean it up). This root object has various properties (defined using
> tiny ids on the prototype of the root object) that are JSObjects as well.
> After an object is instantiated from the prototype (JS_NewObject), to
> protect these objects from GC, I call JS_SetProperty passing in the
> JSObject. This does not work, especially for read-only properties. If I
run
> GC at this point, these objects are destroyed. Note: if I first retrieve
the
> property, then run GC, it is not garbage collected (maybe this is because
it
> is stored in a local root for the return value of the getter?)
>
> Anyway, can someone please set me straight? How should this work? What am
I
> missing?
>
> Thanks,
> - S
>
>

.