Thread: Memory allocation error (Nicely formatted this time)

Once again I would like to appologize for posting that previous mess; hopefully this will be a lot easier to read and understand. The problem that I'm having is that I'm getting the following message during runtime "error for object 0x3fd6a7ef: pointer being reallocated was not allocated." I'm trying to dynamically allocate memory using realloc, but the strange thing is that I get even more bizarre results when I allocate memory statically (e.g. ACCEPTORS acceptor[100]). earlier in the program I defined ACCEPTORS as:

Code:

typedef struct
{
  int index;
  double da_r;
  double theta;
}
ACCEPTORS;

Here is the rest of my function (btw, the user-defined functions work perfectly fine):

Code:

double checkforhbonds(MOLECULE molecule1,int i,MOLECULE molecule2)
{
  double dhb;
  double ijlength,minlength,alength,dhlength,E_hb,jlength,ialength;
  int j,minj,donor,atj,num_acc,a;
  ACCEPTORS *acceptors;

  minlength=100000; //fix this
  num_acc=0;

  dhb = dveclength(molecule1.atom[i].cart); //magnitude of h atom vector

  for(j=0;j<molecule1.numatoms;j++)
    {
      if(j!=i)
	{
	  jlength=dveclength(molecule1.atom[j].cart); //magnitude of test donor
	  ijlength=fabs(dhb-jlength); //distance between h-atom and test donor
	  if(ijlength<minlength)
	    {
	      minlength=ijlength;
	      donor=j;
	    }
	}
    }
  dhlength=dhb-minlength;//length betwen h atom and donor
  for(atj=0,num_acc=0;atj<molecule2.numatoms;atj++)
    {
      alength=dveclength(molecule2.atom[atj].cart);//magnitude of test acceptor vector
      ialength=fabs(dveclength(molecule1.atom[donor].cart)-alength); //distance between donor and prospective acceptor 
	if((ialength)<HBONDTHRESHOLD)
	  {
	    acceptors=realloc(acceptors,(num_acc+1)*sizeof(ACCEPTORS));
	    dhlength=dhb-minlength;
	    acceptors[num_acc].index=atj;//index number in molecule of acceptor
	    acceptors[num_acc].da_r=ialength; //Rda               difference between acceptor and h                           difference between donor and h
	    acceptors[num_acc].theta=dvecangle(dvecsubtr(molecule2.atom[atj].cart,molecule1.atom[i].cart),dvecsubtr(molecule1.atom[donor].cart,molecule1.atom[i].cart)); //theta
	    num_acc++;
	  }
    }
  if(num_acc>0)
    {
     for(a=0;a<=num_acc;a++)
       {
	 E_hb=E_hb+Ehbonds(acceptors[a].da_r,acceptors[a].theta);
       }
    }
    free(acceptors);
  return(E_hb);
}

any help would be very appreciated.