failed build with current mercurial sources

[Ben Abbott]

On Mar 11, 2008, at 1:25 PM, Ben Abbott wrote:

>
> On Mar 11, 2008, at 11:01 AM, John W. Eaton wrote:
>
>> On 11-Mar-2008, Ben Abbott wrote:
>>
>> | Program received signal EXC_BAD_ACCESS, Could not access memory.
>> | Reason: 13 at address: 0x00000000
>> | 0x8fe18b42 in __dyld_misaligned_stack_error ()
>> | (gdb) bt 6
>> | #0  0x8fe18b42 in __dyld_misaligned_stack_error ()
>> | #1  0x94a0b2b5 in atl_f77wrap_zdotc__ ()
>> | #2  0x0017e489 in zqrqhv_ (m=@0xbfffa70c, n=@0xbfffa708,
>> | k=@0xbfffa704, q=0x31f68f0, ldq=@0xbfffa70c, r=0x31f6800,
>> | ldr=@0xbfffa70c, u=0x31f5710, rr=@0xbfffa648) at zqrqhv.f:69
>>
>> The ZDOTC function is a Fortran function returning double complex.
>> There was a recent gfortran change in calling conventions for
>> functions (not subroutines) that return complex variables.  I suspect
>> you are mixing the two methods here, compiling zqrqhv with a compiler
>> that implements one of the methods, and using a version of ATLAS that
>> was compiled to use the other.
>>
>> jwe
>
> ok, I built ATLAS and modified the octave build to use my Altas rather
> than that used by Apple.
>
> Nice deduction, John. The test of qr now passes!
>
> However, now the pcg test produces a "Bus error"
>
> octave:1> test pcg
> panic: Bus error -- stopping myself...
>
> I narrowed down the problem using the short script below.
>
> more off
>
> for N = 10:100;
>   A = zeros (N, N);
>   for i=1 : N - 1 # form 1-D Laplacian matrix
>     A (i:i+1, i:i+1) = [2 -1; -1 2];
>   endfor
>   b = rand (N, 1);
>   disp(sprintf('N = %d; X = A \\ B;',N))
>   X = A \ b;
> endfor
>
> Which produces ...
>
> [...]
> N = 95; X = A \ B;
> N = 96; X = A \ B;
> N = 97; X = A \ B;
> panic: Bus error -- stopping myself...
> attempting to save variables to `octave-core'...
> save to `octave-core' complete
> Bus error
>
> So the problem doesn't seem to be with pcg, but with "\" :-(
>
> I'll spend some more time digging deeper using gdb, but thought I'd
> post in the event someone has a thought on what I might try to resolve
> this.
>
> ... I'm beginning to feel like Alice running down the rabbit hole :-(
>
> Ben

John, my problem above looks very similar to that which Michael  
Friedlander encountered (xGELSD)

http://www.nabble.com/Re%3A-Returning-handles-to-subfunctions-tc15974839.html

| I just compiled release-3-0-x and see that
|
|    for n=1:100; R=triu(randn(n));R(n,n)=0;b=randn(n,1);R\b; end
|
| causes a "panic: Bus error".  Perhaps the xGELSD

Unfortunately, for me pcg continues to fail for the same reason.

This is my first attempt to build Octave using ATLAS in a few months.  
As I haven't had any recent success building with ATLAS, I can't be  
sure what other problems might exist.

Any thoughts?

Ben