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Date: Mon, 03 Mar 2014 16:22:00 -0000
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Subject: Re: [PATCH] record_latest_value: Call release_value_or_incref instead of release_value
From: Doug Evans <xdje42@gmail.com>
To: =?ISO-8859-1?Q?Ludovic_Court=E8s?= <ludo@gnu.org>
Cc: "gdb-patches@sourceware.org" <gdb-patches@sourceware.org>
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On Mon, Mar 3, 2014 at 1:17 AM, Ludovic Court=E8s <ludo@gnu.org> wrote:
> Doug Evans <xdje42@gmail.com> skribis:
>
>> I think this is because its reference counting is wrong.
>> Upon return from record_latest_value, its reference count is still one.
>> However it was one upon entry.  It should be two, right?
>> One for the Scheme wrapper and one for the history entry.
>>
>> (gdb) guile (define histnum (history-append! (make-value 42)))
>
> Indeed, good catch.  Here's how I reproduced it:
>
> --8<---------------cut here---------------start------------->8---
> (gdb) guile (use-modules (gdb))
> (gdb) guile (history-append! (make-value 42))
> 1
> (gdb) p $1
> $2 =3D 42
> (gdb) guile (gc)
> (gdb) p $1
> Segmentation fault
> --8<---------------cut here---------------end--------------->8---
>
> What about adding this to the patch as a test case?

Shall do.  Thanks.