scanner/ parser bug on dot selections

The following program:

int main ()
{
    d = [1,2,3,4][.];

    return 0;
}

after -b1 yields:

int[] main()
/*
 *  main ::  ---
 */
{
  d = sel( ., [ 1, 2, 3, 4 ]) ;
  return( 0);
}

which leads to a segfault at a later stage. Instead it should behave as this one:

int main ()
{
    d = [1,2,3,4][[.]];

    return 0;
}

which yields:

int[] main()
/*
 *  main ::  ---
 */
{
  d = sel( [ . ], [ 1, 2, 3, 4 ]) ;
  return( 0);
}