Subject: bug#29066: 26.0.90; crash in gc involving buffer local symbols

From: Andreas Schwab <[email-masked]>
Date: Tue, 31 Oct 2017 23:00:10 +0100

On Okt 31 2017, Eli Zaretskii <[email-masked]> wrote:

>> From: Andreas Schwab <[email-masked]>
>> Cc: [email-masked],  [email-masked],  [email-masked]
>> Date: Tue, 31 Oct 2017 22:03:26 +0100
>> 
>> >> A symbol on the symbol_free_list is a freed symbol, not available for
>> >> use.
>> >
>> > I guess you are saying that sweep_symbols has a bug?  Because it hits
>> > this "freed" symbol every GC, AFAICT.
>> 
>> Since GC is special, it needs to do special things.
>
> But the crash due to double-free did happen as part of GC doing those
> "special things".

That's why it helps to clear the pointer to the freed memory, instead of
leaving it dangling.

Andreas.

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Andreas Schwab, [email-masked]
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