Re: GNU Prolog crash

[Paulo Moura]

On 2010/11/21, at 16:14, Idelmar Mader wrote:

> Linux jabberwocky 2.6.32-25-generic #45-Ubuntu SMP Sat Oct 16 19:48:22 UTC 
> 2010 i686 GNU/Linux
> 
> Prolog top-Level (GNU Prolog) 1.3.0
> 
> 
> Crash when:
> 
> A = 1.
> A = A + 1.
> 
> -------------------------------------------------------------------------------------------------------------------------------------------------------
> 
> | ?- A = 1.
> 
> A = 1
> 
> yes
> | ?- A = A + 1.
> Falha de segmentação

I.e. Segmentation fault. The goal above creates a rational/infinite term, which 
is not supported (I believe) in GNU Prolog (which is not alone in this regard). 
You can prevent accidental attempts to create a rational term using the 
standard predicate unify_with_occurs_check/2:

| ?- unify_with_occurs_check(A, A+1).

no

Cheers,

Paulo


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