Re: Problem report #53

[Dan Nicolaescu]

Anybody familiar with this code? 

Is it right to assume that XINT (pos) is always >= BUF_BEGV (XBUFFER (buffer)) ?
If yes, then this problem report is FALSE.

  > CID: 53
  > Checker: UNINIT (help)
  > File: emacs/src/textprop.c
  > Function: text_property_stickiness
  > Description: Using uninitialized value "prev_pos" in call to function 
"Fget_text_property"
>
>
  > Event var_decl: Declared variable "prev_pos" without initializer
  > Also see events: [uninit_use_in_call]
>
  > 1730          Lisp_Object prev_pos, front_sticky;
  > 1731          int is_rear_sticky = 1, is_front_sticky = 0; /* defaults */
  > 1732        
>
  > At conditional (1): "buffer == Qnil" taking true path
>
  > 1733          if (NILP (buffer))
  > 1734            XSETBUFFER (buffer, current_buffer);
  > 1735        
>
  > At conditional (2): "pos >> 3 > ((0), (buffer & -8))->begv" taking false 
path
>
  > 1736          if (XINT (pos) > BUF_BEGV (XBUFFER (buffer)))
  > 1737            /* Consider previous character.  */
  > 1738            {
  > 1739              Lisp_Object rear_non_sticky;
  > 1740        
  > 1741              prev_pos = make_number (XINT (pos) - 1);
  > 1742              rear_non_sticky = Fget_text_property (prev_pos, 
Qrear_nonsticky, buffer);
  > 1743        
  > 1744              if (!NILP (CONSP (rear_non_sticky)
  > 1745                         ? Fmemq (prop, rear_non_sticky)
  > 1746                         : rear_non_sticky))
  > 1747                /* PROP is rear-non-sticky.  */
  > 1748                is_rear_sticky = 0;
  > 1749            }
  > 1750        
  > 1751          /* Consider following character.  */
  > 1752          front_sticky = Fget_text_property (pos, Qfront_sticky, 
buffer);
  > 1753        
>
  > At conditional (3): "front_sticky == Qt" taking true path
>
  > 1754          if (EQ (front_sticky, Qt)
  > 1755              || (CONSP (front_sticky)
  > 1756                  && !NILP (Fmemq (prop, front_sticky))))
  > 1757            /* PROP is inherited from after.  */
  > 1758            is_front_sticky = 1;
  > 1759        
  > 1760          /* Simple cases, where the properties are consistent.  */
>
  > At conditional (4): "is_rear_sticky != 0" taking true path
  > At conditional (5): "is_front_sticky == 0" taking false path
>
  > 1761          if (is_rear_sticky && !is_front_sticky)
  > 1762            return -1;
>
  > At conditional (6): "is_rear_sticky == 0" taking false path
>
  > 1763          else if (!is_rear_sticky && is_front_sticky)
  > 1764            return 1;
>
  > At conditional (7): "is_rear_sticky == 0" taking false path
>
  > 1765          else if (!is_rear_sticky && !is_front_sticky)
  > 1766            return 0;
  > 1767        
  > 1768          /* The stickiness properties are inconsistent, so we have to
  > 1769             disambiguate.  Basically, rear-sticky wins, _except_ if the
  > 1770             property that would be inherited has a value of nil, in 
which case
  > 1771             front-sticky wins.  */
>
  > Event uninit_use_in_call: Using uninitialized value "prev_pos" in call to 
function "Fget_text_property" [model]
  > Also see events: [var_decl]
  > At conditional (8): "pos >> 3 == ((0), (buffer & -8))->begv" taking false 
path
>
  > 1772          if (XINT (pos) == BUF_BEGV (XBUFFER (buffer))
  > 1773              || NILP (Fget_text_property (prev_pos, prop, buffer)))
  > 1774            return 1;
  > 1775          else
  > 1776            return -1;