Re: [boost] [random] failure of random_test on Red Hat Linux 2.6.9 ia64

From: Boris Gubenko (Boris.Gubenko_at_[hidden])
Date: 2008-01-10 15:17:11

Boris Gubenko wrote:
> The comment in explicit-failures-markup.xml for random_test for
> intel-linux-9.0 toolset says:
>
>   Reported to Intel as issue 409291, and confirmed as a problem. Probably
>   this relates to a specific Linux-Kernal or GLibC version."
>
> I'm wondering: is this problem specific to a Linux Red Hat 2.6.9 ia64
> Kernal or GLibC version on this platform?

It turns out to be a compiler issue: the test succeeds on this Red Hat
machine when compiled with gcc 4.2.1 instead of 3.4.6. It is consistent
with the fact that, as I mentioned in the previous mail, the test succeeds
on Sandia-gcc-64, a Red Hat system using gcc 4.2.1 and gcc 4.1.1.

I cannot switch to latest gcc on this machine yet, so, I'd like to mark
this test expected failure for "gcc-3.4.6_linux_ia64" toolset. Any
objections?

Thanks,
  Boris

----- Original Message ----- 
From: "Boris Gubenko" <Boris.Gubenko_at_[hidden]>
To: <boost_at_[hidden]>
Cc: "Boris Gubenko" <Boris.Gubenko_at_[hidden]>
Sent: Wednesday, January 09, 2008 3:24 PM
Subject: [boost] [random] failure of random_test on Red Hat Linux 2.6.9 ia64

>  Boost.Random library test random_test fails on linux_ia64_gcc: see
>  <http://tinyurl.com/32hqlu> . It fails with the similar errors on
>  Sandia-pathscale: see <http://tinyurl.com/2va9tz>.
>
>  Both platforms are Red Hat Linux 2.6.9 ia64:
>
>    . linux_ia64_gcc is Red Hat Linux 2.6.9-42.EL
>    . Sandia-pathscale is Red Hat Enterprise Linux 2.6.9-34.0.2.ELsmp
>
>  The test does NOT fail on Sandia-gcc-64 which is a Red Hat Enterprise
>  Linux 2.6.18-8.el5.
>
>  x.cpp below is a reduced reproducer. It passes on every platform I tried
>  it on, including Debian GNU/Linux ia64, except Red Hat Linux 2.6.9-42.EL.
>  On the latter, it fails for long double which is how the original test
>  random_test fails on linux_ia64_gcc.
>
>  On the platforms where it passes it outputs:
>
> *** testing float ***
> g = 1.353399e+00 g2 = 1.353399e+00
> *** passed ***
> *** testing double ***
> g = 1.353399e+00 g2 = 1.353399e+00
> *** passed ***
> *** testing long double ***
> g = 1.353399e+00 g2 = 1.353399e+00
> *** passed ***
>
>  On Red Hat Linux 2.6.9-42.EL it outputs:
>
> *** testing float ***
> g = 1.353399e+00 g2 = 1.353399e+00
> *** passed ***
> *** testing double ***
> g = 1.353399e+00 g2 = 1.353399e+00
> *** passed ***
> *** testing long double ***
> g = nan g2 = 1.000000e+00
> *** failed ***
>
>  The comment in explicit-failures-markup.xml for random_test for
>  intel-linux-9.0 toolset says:
>
>    Reported to Intel as issue 409291, and confirmed as a problem. Probably
>    this relates to a specific Linux-Kernal or GLibC version."
>
>  I'm wondering: is this problem specific to a Linux Red Hat 2.6.9 ia64
>  Kernal or GLibC version on this platform?
>
>  Thanks,
>    Boris
>
> x.cpp
> -----
> #include <cmath>
> #include <stdio.h>
> #include <boost/random.hpp>
>
> template<class URNG, class Dist>
> void instantiate_dist(URNG& urng, const Dist& dist)
> {
>  boost::variate_generator<URNG, Dist> gen(urng, dist);
>  boost::variate_generator<URNG&, Dist> genref(urng, dist);
>  long double g = gen();
>  long double g2 = genref();
>  printf("g = %Le g2 = %Le\n", g, g2);
>  if ( std::abs(g - g2) < 1e-6 ) puts("*** passed ***");
>  else puts("*** failed ***");
> }
>
> template<class T>
> void test()
> {
>  boost::rand48 urng;
>  urng.seed();
>  instantiate_dist(urng, boost::triangle_distribution<T>(1, 1.5, 7));
> }
>
> int main()
> {
>  puts("*** testing float ***");
>  test<float>();
>  puts("*** testing double ***");
>  test<double>();
>  puts("*** testing long double ***");
>  test<long double>();
> }
>
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