bug#6378: all-completions Segfault

[Thierry Volpiatto <thierry.volpiatto@gmail.com>]

Thierry Volpiatto <thierry.volpiatto@gmail.com> writes:

> Stefan Monnier <monnier@IRO.UMontreal.CA> 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.

Program received signal SIGSEGV, Segmentation fault.
0x08151015 in Fall_completions ()

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