dcopy problem with very large arrays

I have run into a problem when using dcopy with very large arrays.  Specifically, I am using dcopy to initialize a very large array to zero before doing other operations, and the dcopy is not setting all of the array to zero.  I think it is having a problem when the input n (ie, the length of the array) is greater than 2^31.  Attached is a simple piece of c++ that demonstrates the issue when run.  When compiled and run on my system, it gives the following output:

testing use of dcopy on very large arrays
trying length = 2147483647
manually setting dbl_array to 1
using dcopy to set dbl_array to 0
trying length = 2147483649
manually setting dbl_array to 1
using dcopy to set dbl_array to 0
problem with dbl_array
dbl_array[0] = 1

A few notes / some more information:

1)  I have found the same problem with dscal and daxpy when n exceed 2^31.

2)  I am using/linking with the ILP64 version of MKL.  I switched to the ILP64 version of MKL so that I could work with matrices that have more than 2^31 entries.  My compile and link command looks like:

   icpc dcopy_test.cc -DMKL_ILP64 -mkl

3)  I am compiling/running this on a scientific linux 6.2 (ie, a redhat like) system.  The system is dual xeon e5-2667 with 128 GB memory, so it isn't running out of memory space.

4)  I am compiling with icpc, whose version is:

Intel(R) C++ Intel(R) 64 Compiler XE for applications running on Intel(R) 64, Version 12.1.4.319 Build 20120410

5)  I am using the MKL libraries from composer_xe_2011_sp1.10.319.  Specifially, an ldd on the simple executable gives:

    linux-vdso.so.1 =>  (0x00007fffdbfff000)
    libmkl_intel_lp64.so => /opt/intel/composer_xe_2011_sp1.10.319/mkl/lib/intel64/libmkl_intel_lp64.so (0x00007f65bcf3f000)
    libmkl_intel_thread.so => /opt/intel/composer_xe_2011_sp1.10.319/mkl/lib/intel64/libmkl_intel_thread.so (0x00007f65bbebf000)
    libmkl_core.so => /opt/intel/composer_xe_2011_sp1.10.319/mkl/lib/intel64/libmkl_core.so (0x00007f65bae49000)
    libiomp5.so => /opt/intel/composer_xe_2011_sp1.10.319/compiler/lib/intel64/libiomp5.so (0x00007f65bab57000)
    libm.so.6 => /lib64/libm.so.6 (0x0000003349800000)
    libstdc++.so.6 => /usr/lib64/libstdc++.so.6 (0x0000003354400000)
    libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x0000003354000000)
    libpthread.so.0 => /lib64/libpthread.so.0 (0x0000003349400000)
    libc.so.6 => /lib64/libc.so.6 (0x0000003348c00000)
    libdl.so.2 => /lib64/libdl.so.2 (0x0000003349000000)
    /lib64/ld-linux-x86-64.so.2 (0x0000003348800000)

Thanks in advance for any insight.

Mark Muller

markmuller@gmail.com