Re: Problem report #16

[Dan Nicolaescu <dann@ics.uci.edu>]

Dan Nicolaescu <dann@ics.uci.edu> writes:

  > CID: 16
  > Checker: FORWARD_NULL (help)
  > File: emacs/src/fontset.c
  > Function: fs_load_font
  > Description: Variable "face" tracked as NULL was dereferenced.
  > 
  > Event var_compare_op: Added "face" due to comparison "face != 0"
  > Also see events: [var_deref_op]
  > At conditional (1): "face != 0" taking false path
  > 
  > 667  	  if (face)
  > 668  	    id = face->fontset;
  > 
  > At conditional (2): "id < 0" taking true path
  > 
  > 669  	  if (id < 0)
  > 670  	    fontset = Qnil;
  > 671  	  else
  > 672  	    fontset = FONTSET_FROM_ID (id);
  > 673  	
  > 
  > At conditional (3): "fontset != Qnil" taking true path
  > At conditional (4): "(fontset & -8)->parent != Qnil" taking true path
  > 
  > 674  	  if (!NILP (fontset)
  > 675  	      && !BASE_FONTSET_P (fontset))
  > 676  	    {
  > 677  	      elt = FONTSET_REF_VIA_BASE (fontset, c);
  > 
  > At conditional (5): "elt != Qnil" taking true path
  > 
  > 678  	      if (!NILP (elt))
  > 679  		{
  > 680  		  /* A suitable face for C is already recorded, which means
  > 681  		     that a proper font is already loaded.  */
  > 682  		  int face_id = XINT (elt);
  > 683  	
  > 684  		  xassert (face_id == face->id);
  > 
  > At conditional (6): "face_id < ((f)->face_cache)->used" taking false path
  > 
  > 685  		  face = FACE_FROM_ID (f, face_id);
  > 
  > Event var_deref_op: Variable "face" tracked as NULL was dereferenced.
  > Also see events: [var_compare_op]
  > 
  > 686  		  return (*get_font_info_func) (f, face->font_info_id);
  > 687  		}


This problem could happen if fs_load_font was called with face=NULL
and id>0. Can that happen?