[PPL-devel] Bug affecting PPL 0.10 on big-endian architectures

[Roberto Bagnara]

Abramo Bagnara wrote:
> Michael Tautschnig ha scritto:
>> Hi all,
>>
>>> P.S. The bug proves that no one ever ran `make check' on PPL 0.10
>>>      on a PowerPC machine and reported back the results.  If you
>>>      have any idea how to make sure this does not happen again...
>>>
>> Finally ppl 0.10-2 has made its way through nearly all the build daemons (armel
>> is missing, but arm was ok), and only a single check fails, and it only fails on
>> alpha: generalizedaffineimage2 (from Octagonal_Shape) results in an uncaught
>> exception. See also
>> http://buildd.debian.org/build.php?&pkg=ppl&ver=0.10-2&arch=alpha&file=log
>>
>> Do you have access to an alpha machine or can you tell from the source what
>> could be going wrong there? Of course, it may also be an architecture-specific
>> compiler problem ... 
>>
>> If you need any help, just contact me.
> 
> We've tried hard, but we've been unable to reproduce this behavior using
> stock PPL 0.10 configured as found in your log file:
> 
> configure --build alpha-linux-gnu --host alpha-linux-gnu
> --enable-interfaces=c,cxx --disable-ppl_lpsol --disable-ppl_lcdd
> CFLAGS="-Wall -g -O2"
> 
> It would be very interesting to check with gdb where the untrapped
> exception has been generated.
> 
> Here below you find info about testing machine (which is the only alpha
> we have access to).
> 
> $ cat /proc/cpuinfo
> cpu			: Alpha
> cpu model		: EV56
> cpu variation		: 7
> cpu revision		: 0
> cpu serial number	:
> system type		: Rawhide
> system variation	: Tincup
> system revision		: 0
> system serial number	: AY74642662
> cycle frequency [Hz]	: 399638195 est.
> timer frequency [Hz]	: 1200.00
> page size [bytes]	: 8192
> phys. address bits	: 40
> max. addr. space #	: 127
> BogoMIPS		: 738.12
> kernel unaligned acc	: 0 (pc=0,va=0)
> user unaligned acc	: 17680637 (pc=20b13c08,va=783d2004)
> platform string		: AlphaServer 1200 5/400 4MB
> cpus detected		: 1
> cpus active		: 1
> cpu active mask		: 0000000000000001
> L1 Icache		: 8K, 1-way, 32b line
> L1 Dcache		: 8K, 1-way, 32b line
> L2 cache		: 96K, 3-way, 64b line
> L3 cache		: 4096K, 1-way, 64b line
> $ cat /proc/version
> Linux version 2.6.18-6-alpha-smp (Debian 2.6.18.dfsg.1-18etch6)
> (dannf at debian.org) (gcc version 4.1.2 20061115 (prerelease) (Debian
> 4.1.1-21)) #1 SMP Fri Jun 6 23:28:12 UTC 2008
> $ g++ -v
> Using built-in specs.
> Target: alphaev56-unknown-linux-gnu
> Configured with: ../gcc-4.3.2/configure
> --prefix=/opt/cfarm/release/4.3.2 --enable-languages=c,c++
> --enable-__cxa_atexit --disable-nls --enable-threads=posix
> --disable-multilib --with-mpfr=/opt/cfarm/mpfr-2.3.1
> Thread model: posix
> gcc version 4.3.2 (GCC)

Hi Michael,

would it be possible to access a machine where the problem
manifests itself?  Alternatively, can someone run that
test program under GDB and tell us which exception is
thrown?
All the best,

    Roberto

-- 
Prof. Roberto Bagnara
Computer Science Group
Department of Mathematics, University of Parma, Italy
http://www.cs.unipr.it/~bagnara/
mailto:bagnara at cs.unipr.it