Re: Trying to understand trace limit

[Aleix Conchillo Flaqué]

It seems like a bug in 2.2.7 (or even 2.x). I can only suggest reporting it
to bug-guile@gnu.org and guile-devel@gnu.org and update to Guile 3.x.

Aleix

On Sat, Oct 3, 2020 at 1:39 PM Dave Musicant <dmusicant@carleton.edu> wrote:

> I'm using Guile 2.2.7, under Ubuntu 20.04.
>
>
> --
> Dave
>
> On 10/3/20 2:15 AM, Aleix Conchillo Flaqué wrote:
>
>
> Hi Dave,
>
> On Mon, Sep 28, 2020 at 10:06 AM Dave Musicant <dmusicant@carleton.edu>
> wrote:
>
>> Hi all,
>>
>> I'm seeing some strange behavior with tracing code, which I'd love some
>> help understanding. I've boiled it down to the following simplified
>> example:
>>
>> (define count
>>    (lambda (n)
>>      (if (equal? n 1) 1
>>          (+ 1 (count (- n 1))))))
>>
>> ,tr (count 92)
>>
>>
>> When I run the above code (in a fresh Guile instance, via redirecting
>> from a file), the trace runs to completion.
>>
>> However, when I run this version of the code from a file, which runs the
>> function twice...
>>
>> (define count
>>    (lambda (n)
>>      (if (equal? n 1) 1
>>          (+ 1 (count (- n 1))))))
>>
>> ,tr (count 10)   ; runs to completion
>> ,tr (count 92)   ; dies mid-trace
>>
>>
>> ... then the trace dies when it runs the second time, in something that
>> must be some sort of stack overflow, though the error is fairly cryptic:
>>
>> While executing meta-command:
>> In procedure +: Wrong type argument in position 1: #<unspecified>
>>
>> What's happening from a memory perspective where tracing the code the
>> first time affects how much memory is available for the second time? It
>> seems that the first run shouldn't affect the stack limit of the second,
>> but something is going on.
>>
>> Thanks for the help.
>> Dave
>>
>
> I've tried it with Guile 3.0.4 (in macOS) and I didn't get this error.
> What version of Guile and OS are you using?
>
> Aleix
>
>
>
>
>