Peter's Patch to Sean's Patched lil-gp Kernel

Peter Anderson noted the following bug in the ERC facility. I've not yet verified that this bug exists or that the patch works, so you're own your own. I include his message to me below:

Use of ERC terminal on the form "name:ERCindex" do not work.

The ECR terminal nodes are not constructed.
The first call to "mod_read_tree_recurse" 
eind with the ERC structure is NULL, and the call to
"get_function_by_name" core dump on a I:1 structure.

I have modified the function "mod_read_tree_recurse" in populate.c so
the user can use ERC integer constant. By supplying a function to
insert the constant in the DATATYPE structure. The chances are as followed.
in the files:

populate.c
ckpoint.c
 

a) "get_function_by_name" in ckpoint.c is made safe by changing:
  
        *ep = eind[j];
        (*ep)->f = fs->cset+i;

change to:

        if (eind != NULL) {
            *ep = eind[j];
            (*ep)->f = fs->cset+i;
        }

b) "mod_read_tree_recurs" catch the ERCindex before the call to 
"get_function_by_name"

  f = get_function_by_name ( tree, string, &ep, eind );

chance to:

  sl = strlen ( string );
  for ( si = 0; si < sl; ++si )
    {

      if ( string[si] == ':' )
        {
          /* names of the form "name:index" are chopped at the colon,
             and the value of the index saved. */
          string[si] = 0;
          ECRvalue = atoi ( string+si+1 );
          break;
        }
    }

  f = get_function_by_name ( tree, string, &ep, eind );

where sl,si are int.

c) create the ERC'c in "mod_read_tree_recurse"

  switch ( f->type )
    {
    case TERM_NORM:
    case TERM_ARG:
    case EVAL_TERM:
      break;
    case TERM_ERC:
      /* stt_record the ERC address as the next lnode in the array. */
      gensp_next(space)->d = ep; 
      break;

chance to:

  switch ( f->type )
    {
    case TERM_NORM:
    case TERM_ARG:
    case EVAL_TERM:
      break;
    case TERM_ERC:
      /* stt_record the ERC address as the next lnode in the array. */
      new_ECR = gensp_next(space);
      new_ECR->d = new_ephemeral_const ( f );
      set_ECR_value(&new_ECR->d->d , ECRvalue);
      /* gensp_next(space)->d = ep; */
      break;

The function "set_ECR_value(&new_ECR->d->d , ECRvalue);" is user defined
in my case it is:

void set_ECR_value(DATATYPE *d, int ECRvalue)
{
  d->input = ECRvalue;
}


d) before the first call to "mod_read_tree_recurse" is there a call to
"gensp_reset(0)" that is not needed.

  case LOAD_FILE:
    gensp_reset(0); 
    mod_read_tree_recurse( 0, NULL, dataum[j], j, buf, 1);
    /* need to do something here about limit checking */
    break;

chance to:

  case LOAD_FILE:
    /* gensp_reset(0); not needed there is a call before the switch */
    mod_read_tree_recurse( 0, NULL, dataum[j], j, buf, 1);
    /* need to do something here about limit checking */
    break;