********> bugfix.90
Author:   Bill Ross
Date:     3/11/97

Programs: Carnal

Severity: Moderate

Problem:  Can crash in HBOND when specifying a DONOR group.

Affects:  Especially exactly defined hbond donor groups containing
          _only_ the donor (heavy) atoms.

Cause:    In sizing arrays it was not considered that heavy atoms can 
          donate more than one covalently bound H to hbonds. Thus if 
          the number of 'extra' H's on the donor atoms in the group
          exceeds the number of non-donor atoms, the program is likely
          to crash at some point during the calculation.


Fix:  Make the following change to hbond.c:
---------------------------------------------------------------------
*** OLD hbond.c
--- NEW hbond.c
***************
*** 403,412
  	grp = grptr->idunion.group.Atomlist;
  	grpend = (int *)( (int)grp + sizeof(int) * grptr->idunion.group.natoms);
  
! 	list1 = (int *) get(min(prm->Nbonh, grptr->idunion.group.natoms)
! 								 * sizeof(int));
! 	list2 = (int *) get(min(prm->Nbonh, grptr->idunion.group.natoms)
! 								 * sizeof(int));
  	hbptr->idunion.hb.donor1 = list1;
  	hbptr->idunion.hb.donor2 = list2;
  

--- 403,410 -----
  	grp = grptr->idunion.group.Atomlist;
  	grpend = (int *)( (int)grp + sizeof(int) * grptr->idunion.group.natoms);
  
! 	list1 = (int *) get(prm->Nbonh * sizeof(int));
! 	list2 = (int *) get(prm->Nbonh * sizeof(int));
  	hbptr->idunion.hb.donor1 = list1;
  	hbptr->idunion.hb.donor2 = list2;
  
---------------------------------------------------------------------

Temporary workarounds: include attached H's in donor group

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