将GNU科学库与Code :: Blocks一起使用时出错

Question

I am having an extraordinary problem with my current Code::Blocks (GNU GCC compiler) setup. The compiler seems to selectively run some GSL functions, but seems for some reason to have great problems when commanded to execute other GSL functions.

For example, I have lifted the following code from the following destination: https://www.gnu.org/software/gsl/manual/html_node/Example-programs-for-matrices.html

I assume that because the code is derived from the official GNU website, that the code is correct:

#include <math.h>
#include <stdio.h>
#include <gsl/gsl_matrix.h>
#include <gsl/gsl_blas.h>

int
main (void)
{
  size_t i,j;

  gsl_matrix *m = gsl_matrix_alloc (10, 10);

  for (i = 0; i < 10; i++)
    for (j = 0; j < 10; j++)
      gsl_matrix_set (m, i, j, sin (i) + cos (j));

  for (j = 0; j < 10; j++)
    {
      gsl_vector_view column = gsl_matrix_column (m, j);
      double d;

      d = gsl_blas_dnrm2 (&column.vector);

      printf ("matrix column %d, norm = %g\n", j, d);
    }

  gsl_matrix_free (m);

  return 0;
}

From debugging, I have learned that the source of the error is the following line:

d = gsl_blas_dnrm2 (&column.vector);

The compiler crashes at this point and prints the following error message:

Process returned -1073741819 <0xC0000005>

I have spent a lot of time trying to discover the source of the bug but have sadly not had much success. I am generally not sure why there is a crash at all. The debugger prints no warnings or error messages.

Answer 1

I'm going to suggest that perhaps you have mismatched headers and libraries. Perhaps there is more than one version of GSL installed. You have the headers from one version referenced in your source, and the linker is referencing the libs from other version.

I went looking up the typedef of the gsl_vector_view and ended up here, and you may be even able to discern that this version doesn't even support the vector member of that struct type.

You will get this 0xC0000005 error, typically when you use some unitialised pointer. Its not that your pointer is uninitialised here though .. I'd say what's happening is the 'vector' bit of &column.vector is being interpreted as something other than what is intended.

In summary, I think this is some kind of environmental issue, perhaps with your linker settings? There are some details on how to configure these here: http://www.learncpp.com/cpp-tutorial/a3-using-libraries-with-codeblocks/

Hope this helps.