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Subject: Re: [hwloc-users] Problems on SMP with 48 cores
From: Hartmut Kaiser (hartmut.kaiser_at_[hidden])
Date: 2012-03-13 12:04:44


> > But the problems I was seeing were not MSVC specific. It's a
> > proliferation of arcane (non-POSIX) function use (like strcasecmp,
> > etc.) missing use of HAVE_UNISTD_H, HAVE_STRINGS_H to wrap
> > non-standard headers, unsafe mixing of
> > int32<->int64 data types, reliance on int (and other types) having a
> > certain bit-size, totally unsafe shift operations, wide use of
> > (non-C-standard) gcc extensions, etc. Should I go on?

More investigation shows that the code currently assumes group (and
processor) masks to be 32 bit, which is not true on 64 bit systems. For
instance this (topology-windows.c: line 643):

    hwloc_bitmap_from_ith_ulong(obj->cpuset, GroupMask[i].Group,
GroupMask[i].Mask);

fails as GroupMask[i].Mask is a 64 bit value.

There are probably other places where the same assumption leads to problems.

Regards Hartmut
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