Re: Bus error in GP:

["Justin C. Walker" <justin@mac.com>]

Hi, Dave,

On Jun 25, 2006, at 14:55 , David R. Morrison wrote:

> On Fri, 9 Jun 2006 17:57:26 -0400, Justin C. Walker  
> <justin@mac.com> wrote:
>
> I get a bus error with the following:
>
> ? K=nfinit(y^3-2);
> ? L=rnfinit(K,x^2+x+1);
>
>   *** rnfinit: bug in GP (Bus Error), please report
>
> I can confirm this, as I was getting the same error today, on pari- 
> gp-2.3.0 during 'make bench'.  My experimentation suggests that the  
> error is caused by a compiler bug in XCode 2.2.1 and earlier, and  
> is resolved by switching to XCode 2.3.
>
> Justin, can you confirm?  Was there a difference in compilers  
> between your two machines?

Here's the setup: I tried this in the context of SAGE, on Mac OS X  
10.4.6, on a PowerPC G4 (2x2.7GHz) and on a MacBook Pro Core Duo  
(2.16 GHz).  I get the same failure in both cases (using 'gp_console 
()' in SAGE to talk directly to 'gp').

If I build Pari/gp stand-alone, I do not see the problem.

In all cases, I am using the 2.3.0 release of Pari/gp.

My current guess is that the problem lies with GMP 4.2 (or the gcc  
compilers that build GMP): for my stand-alone use, I have GMP 4.1.4  
installed.  SAGE uses GMP 4.2.

I have not yet scraped together the cycles to verify this, so it's  
only a hunch at this point.

I have not tried rebuilding since upgrading to Xcode 2.3 and the  
corresponding gcc compilers.  I'll try that later today.

Cheers,

Justin

--
Justin C. Walker, Curmudgeon-At-Large
Director
Institute for the Enhancement of the Director's Income
--------
"Weaseling out of things is what separates us from the animals.
 Well, except the weasel."
      - Homer J Simpson
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