Subject: bug#6378: all-completions Segfault

From: Thierry Volpiatto <[email-masked]>
Date: Wed, 09 Jun 2010 07:13:31 +0200

Stefan Monnier <[email-masked]> writes:

>> Although I don't understand why the code-path for the vector
>> version can't be simplified as in the following patch, which also
>> fixes the problem AFAICT:
>
>> diff --git a/src/minibuf.c b/src/minibuf.c
>> index ad81bfd..c6aae27 100644
>> --- a/src/minibuf.c
>> +++ b/src/minibuf.c
>> @@ -1610,22 +1610,14 @@ with a space are ignored unless STRING itself starts with a space.  */)
>>  	}
>>        else if (type == 2)
>>  	{
>> -	  if (!EQ (bucket, zero))
>> -	    {
>> -	      elt = bucket;
>> -	      eltstring = elt;
>> -	      if (XSYMBOL (bucket)->next)
>> -		XSETSYMBOL (bucket, XSYMBOL (bucket)->next);
>> -	      else
>> -		XSETFASTINT (bucket, 0);
>> -	    }
>> -	  else if (++index >= obsize)
>> -	    break;
>> -	  else
>> -	    {
>> -	      bucket = XVECTOR (collection)->contents[index];
>> -	      continue;
>> -	    }
>> +          if ( index < obsize )
>> +            {
>> +              elt = bucket;
>> +              eltstring = elt;
>> +              bucket = XVECTOR (collection)->contents[++index];
>> +            }
>> +          else
>> +            break;
>>  	}
>>        else /* if (type == 3) */
>>  	{
>
> IIUC this would only loop through all the buckets, without looping
> through each bucket's linked list.
> Compare (length obarray)
> and     (let ((i 0)) (mapatoms (lambda (_) (incf i)) obarray) i)

Don't know if that related but

(completing-read "test: " [1 2 3 23 24 34 26 40 28])

test: 2 ==> TAB

instead of failing crash emacs.

 -- 
Thierry Volpiatto
Gpg key: http://pgp.mit.edu/