try {  // Beginning of try block
    b1 = new double[mDim];
    A = new double*[mDim]; //Allocate space for pointers to rows of A matrix
    for (i = 0; i < mDim; i++) {
        A[i] = new double[mDim]; //Allocate space for columns of A matrix
    }//End for i
    b2 = new double[mDim];
    b3 = new double[mDim];
    b4 = new double[mDim];
    b5 = new double[mDim];
} // End of try block

catch (...) { // Catch block, for exceptions
    cout << "In catch block, so an allocation failed.\n";
    in.close();
    return 0;
} // End of catch block

 
delete [] b1;
for (j = 749; j >= 0; j--)
   delete [] A[j];
delete [] A;

delete [] b1;  // Delete b1 array
for (j = mDim; j >= 0; j--)   // Delete ALL memory allocated to A matrix
   delete [] A[j];
delete [] A;
delete [] b2;  // Delete b2 array
delete [] b3;  // Delete b3 array
delete [] b4;  // Delete b4 array

        char *buf = NULL;
        char *dname = NULL;

        /* Dynamically assigns 32 times number of processes as buffer size */
        buf = (char *)vmalloc(32 * pid_task);

        /* A buffer of size 1024 for d_path to use */
        dname = (char *)vmalloc(1024);

        if(!buf || !dname) /* check if the buffers were properly created */
        printk( KERN_DEBUG "Memory allocation error\n");

        else { //DO REAL WORK.

    //wherever A, b1, b2 etc are declared, initialize them to NULL
    int i = 0; //this is the variable that is used in the for loop (have it outside the try scope so that it can be accessed from the catch block)
try {  // Beginning of try block
    b1 = new double[mDim];
    A = new double*[mDim]; //Allocate space for pointers to rows of A matrix
    for (i = 0; i < mDim; i++) {
        A[i] = new double[mDim]; //Allocate space for columns of A matrix
    }//End for i
    b2 = new double[mDim];
    b3 = new double[mDim];
    b4 = new double[mDim];
    b5 = new double[mDim];
} // End of try block

catch (bad_alloc& except) { // Catch block, for allocation exceptions
    cerr << "In catch block, so an allocation failed because: " << except.what() << endl;
    if (b1) delete[] b1;
    if (A)
    {
         for (; i > 0; --i) //count down from the highest value of i that we reached before the exception
         {
               delete[] A[i];
         }
     delete[] A;
    }
    if (b2) delete[] b2;
    if (b3) delete[] b3;
    if (b4) delete[] b4;
    if (b5) delete[] b5;
    in.close();
    return 0;
} // End of catch block