zfeast_hrci initialization shows strange behaviour

[Christian_M_3]

Hi all,

i am working my way through the example zexample_sparse_rci_c.c. I have it working now for my matrix, BUT found a strange behaviour for the input arrays Aq and Sq:

when declaring them like this:

MKL_Complex16  Aq[M0SQUARE]; (where MOSquare is an integer) everything works fine.

When declaring them like

MKL_Complex16 *Sq = new MKL_Complex16[M0SQUARE];

the first call to zfeast_hrci  fails with:

Thread #1 [feastTrial] 5489 [core: 2] (Suspended : Signal : SIGSEGV:Segmentation fault)    
    mkl_feast_zfeast_hrci() at 0x7ffff617fedf    
    zfeast_hrci_() at 0x7ffff7959141    
    testAddition() at feastTrial.cpp:251 0x4047da    
    0x0    

. Strangely enough: when declaring workc and work with new .... no problems occur. 

What am I missing here?

I want to have all memory on the heap in order to cope with LARGE matrices.

[Ying_H_Intel]

Hi Christian, 

how do you declare the M0SQUARE?  Could you please provide us one test case? 

I use the zexample_sparse_rci_c.c -> covert to CPP file.  with MKL_Complex16 *Sq = new MKL_Complex16[M0SQUARE]; 

It seems work fine.  I attached the cpp code for your reference. 

Best Regards,

Ying 

[Christian_M_3]

Hello Ying,

MKL_INT       M0;

    if (dimension < 500)
    {
        M0=dimension*0.5;
    }
    else
    {
        M0=dimension*0.1;
    }
    int workSize = M0*dimension;
    MKL_INT M0StartValue = M0;
    MKL_INT M0SQUARE = M0*M0;

The values in my testcase are dimension=495, M0= 247 and so on.

One more thing I forgot to mention:

I use the gcc compiler, (4.8.4) on ubuntu linux.

Thanks for your help.

Christian

[Christian_M_3]

OK. It seems to me that cannot mix the declaration/allocation types with my version of gcc

(i.e. having

MKL_Complex16  Aq[M0SQUARE]; (where MOSquare is an integer) everything works fine.

and

MKL_Complex16 *Sq = new MKL_Complex16[M0SQUARE];

in the program

)

replacing all declarations with new [] helped.

 BUT now comes the next problem:

When trying to delete those arrays, the program crashes when trying to delete [] Sq; claiming the pointer would be invalid.

Any ideas why this happens? All other pointers can be deleted properly.

[Ying_H_Intel]

Hi Christian, 

is there any special compiler option in your CPP code?   or is there any special code (for example, delete [] Sq in while loop)  in your CPP code? 

I add

 printf( "Max of (conjugate transposed of X)*X-I %.15e \n", smax);

    delete [] Sq;

    
    return 0;
}

 tried the command; 

 $source /opt/intel/compilers_and_libraries_2016.2.181/linux/mkl/bin/mklvars.sh intel64

 $g++ zexample_sparse_rci_c.cpp  -lmkl_intel_lp64 -lmkl_sequential -lmkl_core -lm

hu5@ivb01-ub:~/Merry$ ./a.out

    FEAST ZFEAST_HRCI EXAMPLE PROGRAM
Sparse matrix size  10
 Search interval [ 2.000000000000000e+00, 1.200000000000000e+01 ]
Intel MKL Extended Eigensolvers: complex double precision driver
Intel MKL Extended Eigensolvers: List of input parameters fpm(1:64)-- if different from default
Intel MKL Extended Eigensolvers: fpm(1)=1
Intel MKL Extended Eigensolvers: fpm(6)=1

..

It run fines.  

yhu5@ivb01-ub:~/Merry$ g++ --version
g++ (Ubuntu/Linaro 4.8.1-10ubuntu9) 4.8.1. 

Could you provide us a test main cpp file, so we can debug at our sides?

Regards,

Ying