Problem report #113: base/src/emacs/src/coding.c (decode_coding_object); UNINIT

[Dan Nicolaescu]

CID: 113
Checker: UNINIT (help)
File: base/src/emacs/src/coding.c
Function: decode_coding_object
Description: Using uninitialized value "saved_pt_byte" in call to function 
"temp_set_point_both"

Event var_decl: Declared variable "saved_pt_byte" without initializer
Also see events: [uninit_use][uninit_use][uninit_use_in_call]

7141      int saved_pt = -1, saved_pt_byte;
7142      int need_marker_adjustment = 0;
7143      Lisp_Object old_deactivate_mark;
7144    
7145      old_deactivate_mark = Vdeactivate_mark;
7146    

At conditional (1): "dst_object == Qnil" taking true path

7147      if (NILP (dst_object))
7148        {
7149          destination = coding->destination;
7150          dst_bytes = coding->dst_bytes;
7151        }
7152    
7153      coding->src_object = src_object;
7154      coding->src_chars = chars;
7155      coding->src_bytes = bytes;

At conditional (2): "chars < bytes" taking true path

7156      coding->src_multibyte = chars < bytes;
7157    

At conditional (3): "src_object & 7 == 3" taking false path

7158      if (STRINGP (src_object))
7159        {
7160          coding->src_pos = from;
7161          coding->src_pos_byte = from_byte;
7162        }

At conditional (4): "src_object & 7 == 4" taking true path
At conditional (5): "((0), (src_object & -8))->size & 4611686018427518976 == 
4611686018427518976" taking true path

7163      else if (BUFFERP (src_object))
7164        {
7165          set_buffer_internal (XBUFFER (src_object));

At conditional (6): "from != ((current_buffer)->text)->gpt" taking true path

7166          if (from != GPT)
7167            move_gap_both (from, from_byte);

At conditional (7): "src_object == dst_object" taking false path

7168          if (EQ (src_object, dst_object))
7169            {
7170              struct Lisp_Marker *tail;
7171    
7172              for (tail = BUF_MARKERS (current_buffer); tail; tail = 
tail->next)
7173                {
7174                  tail->need_adjustment
7175                    = tail->charpos == (tail->insertion_type ? from : to);
7176                  need_marker_adjustment |= tail->need_adjustment;
7177                }
7178              saved_pt = PT, saved_pt_byte = PT_BYTE;
7179              TEMP_SET_PT_BOTH (from, from_byte);
7180              current_buffer->text->inhibit_shrinking = 1;
7181              del_range_both (from, from_byte, to, to_byte, 1);
7182              coding->src_pos = -chars;
7183              coding->src_pos_byte = -bytes;
7184            }
7185          else
7186            {
7187              coding->src_pos = from;
7188              coding->src_pos_byte = from_byte;
7189            }
7190        }
7191    

At conditional (8): "(coding)->common_flags & 4096 != 0" taking true path

7192      if (CODING_REQUIRE_DETECTION (coding))
7193        detect_coding (coding);
7194      attrs = CODING_ID_ATTRS (coding->id);
7195    

At conditional (9): "dst_object == Qt" taking true path

7196      if (EQ (dst_object, Qt)
7197          || (! NILP (CODING_ATTR_POST_READ (attrs))
7198              && NILP (dst_object)))
7199        {

At conditional (10): "(coding)->common_flags & 256 == 0" taking true path

7200          coding->dst_multibyte = !CODING_FOR_UNIBYTE (coding);
7201          coding->dst_object = code_conversion_save (1, 
coding->dst_multibyte);
7202          coding->dst_pos = BEG;
7203          coding->dst_pos_byte = BEG_BYTE;
7204        }
7205      else if (BUFFERP (dst_object))
7206        {
7207          code_conversion_save (0, 0);
7208          coding->dst_object = dst_object;
7209          coding->dst_pos = BUF_PT (XBUFFER (dst_object));
7210          coding->dst_pos_byte = BUF_PT_BYTE (XBUFFER (dst_object));
7211          coding->dst_multibyte
7212            = ! NILP (XBUFFER (dst_object)->enable_multibyte_characters);
7213        }
7214      else
7215        {
7216          code_conversion_save (0, 0);
7217          coding->dst_object = Qnil;
7218          /* Most callers presume this will return a multibyte result, and 
they
7219             won't use `binary' or `raw-text' anyway, so let's not worry 
about
7220             CODING_FOR_UNIBYTE.  */
7221          coding->dst_multibyte = 1;
7222        }
7223    
7224      decode_coding (coding);
7225    

At conditional (11): "(coding)->dst_object & 7 == 4" taking true path
At conditional (12): "((0), ((coding)->dst_object & -8))->size & 
4611686018427518976 == 4611686018427518976" taking true path

7226      if (BUFFERP (coding->dst_object))
7227        set_buffer_internal (XBUFFER (coding->dst_object));
7228    

At conditional (13): "((0), (attrs & -8))->contents[9] != Qnil" taking true path

7229      if (! NILP (CODING_ATTR_POST_READ (attrs)))
7230        {
7231          struct gcpro gcpro1, gcpro2, gcpro3, gcpro4, gcpro5;
7232          EMACS_INT prev_Z = Z, prev_Z_BYTE = Z_BYTE;
7233          Lisp_Object val;
7234    
7235          TEMP_SET_PT_BOTH (coding->dst_pos, coding->dst_pos_byte);
7236          GCPRO5 (coding->src_object, coding->dst_object, src_object, 
dst_object,
7237                  old_deactivate_mark);
7238          val = safe_call1 (CODING_ATTR_POST_READ (attrs),
7239                            make_number (coding->produced_char));
7240          UNGCPRO;

At conditional (14): "val & 7 != 0" taking false path
At conditional (15): "val >> 3 < 0" taking false path
At conditional (16): "0" taking false path

7241          CHECK_NATNUM (val);
7242          coding->produced_char += Z - prev_Z;
7243          coding->produced += Z_BYTE - prev_Z_BYTE;
7244        }
7245    

At conditional (17): "dst_object == Qt" taking true path

7246      if (EQ (dst_object, Qt))
7247        {
7248          coding->dst_object = Fbuffer_string ();
7249        }
7250      else if (NILP (dst_object) && BUFFERP (coding->dst_object))
7251        {
7252          set_buffer_internal (XBUFFER (coding->dst_object));
7253          if (dst_bytes < coding->produced)
7254            {
7255              destination = xrealloc (destination, coding->produced);
7256              if (! destination)
7257                {
7258                  record_conversion_result (coding,
7259                                            CODING_RESULT_INSUFFICIENT_DST);
7260                  unbind_to (count, Qnil);
7261                  return;
7262                }
7263              if (BEGV < GPT && GPT < BEGV + coding->produced_char)
7264                move_gap_both (BEGV, BEGV_BYTE);
7265              bcopy (BEGV_ADDR, destination, coding->produced);
7266              coding->destination = destination;
7267            }
7268        }
7269    

At conditional (18): "saved_pt >= 0" taking true path

7270      if (saved_pt >= 0)
7271        {
7272          /* This is the case of:
7273             (BUFFERP (src_object) && EQ (src_object, dst_object))
7274             As we have moved PT while replacing the original buffer
7275             contents, we must recover it now.  */
7276          set_buffer_internal (XBUFFER (src_object));
7277          current_buffer->text->inhibit_shrinking = 0;

At conditional (19): "saved_pt < from" taking false path

7278          if (saved_pt < from)

Event uninit_use_in_call: Using uninitialized value "saved_pt_byte" in call to 
function "temp_set_point_both" [model]
Also see events: [var_decl][uninit_use][uninit_use]

7279            TEMP_SET_PT_BOTH (saved_pt, saved_pt_byte);

At conditional (20): "saved_pt < (from + chars)" taking false path

7280          else if (saved_pt < from + chars)
7281            TEMP_SET_PT_BOTH (from, from_byte);

At conditional (21): "(current_buffer)->enable_multibyte_characters != Qnil" 
taking true path

7282          else if (! NILP (current_buffer->enable_multibyte_characters))

Event uninit_use: Using uninitialized value "saved_pt_byte"
Also see events: [var_decl][uninit_use][uninit_use_in_call]

7283            TEMP_SET_PT_BOTH (saved_pt + (coding->produced_char - chars),
7284                              saved_pt_byte + (coding->produced - bytes));
7285          else

Event uninit_use: Using uninitialized value "saved_pt_byte"
Also see events: [var_decl][uninit_use][uninit_use_in_call]

7286            TEMP_SET_PT_BOTH (saved_pt + (coding->produced - bytes),
7287                              saved_pt_byte + (coding->produced - bytes));
7288    
7289          if (need_marker_adjustment)