pure-lang-users

[pure-lang-users] Segfault using lambda

[Chris D. <chr...@do...>]

I get a segfault using current SVN (r10) with the following:

> let y=(\a b -> a+b);y 1 5;

This works:

> (\a b -> a+b) 1 5 ;

Am I misunderstanding how let works?

Chris.
-- 
http://www.bluishcoder.co.nz

Re: [pure-lang-users] Segfault using lambda

[Albert G. <Dr....@t-...>]

Chris Double wrote:
> I get a segfault using current SVN (r10) with the following:
> 
>> let y=(\a b -> a+b);y 1 5;
> 
> Am I misunderstanding how let works?

No, it's a bug. Apparently the closure gets garbage-collected while it's
still bound by the variable. I think I already know where that happens.

Thanks folks for all the great bug reports, keep them rolling. :)

Albert

-- 
Dr. Albert Gr"af
Dept. of Music-Informatics, University of Mainz, Germany
Email:  Dr....@t-..., ag...@mu...
WWW:    http://www.musikinformatik.uni-mainz.de/ag

Re: [pure-lang-users] Segfault using lambda

[Albert G. <Dr....@t-...>]

> Chris Double wrote:
>> I get a segfault using current SVN (r10) with the following:
>>
>>> let y=(\a b -> a+b);y 1 5;
>> Am I misunderstanding how let works?
> 
> No, it's a bug. Apparently the closure gets garbage-collected while it's
> still bound by the variable. I think I already know where that happens.

Ok, that one is now fixed, too. This was a bit trickier than expected,
since not the runtime representation of the closure was
garbage-collected too early, but the executable code associated with it,
causing wrong machine code to be executed.

Albert

-- 
Dr. Albert Gr"af
Dept. of Music-Informatics, University of Mainz, Germany
Email:  Dr....@t-..., ag...@mu...
WWW:    http://www.musikinformatik.uni-mainz.de/ag