Re: [PATCH] improve out-of-bounds checking with GCC 10 attribute access [BZ #25219]

[Martin Sebor <msebor@gmail.com>]

On 5/1/20 4:02 PM, DJ Delorie wrote:
> Martin Sebor <msebor@gmail.com> writes:
>> Thanks for the careful review!
> 
> This new version LGTM.
> 
> Reviewed-by: DJ Delorie <dj@redhat.com>
> 
> (but IMHO a second set of eyes would be good for this one)
> 
>> Yes, that's wrong.  Good catch!  I completely missed stdio when
>> testing so I also didn't notice I forgot to add the attribute to
>> fgets() itself.  I've fixed that in the updated patch.
> 
> Ok.
> 
>>> IMHO comment should state that the first argument is index 1.
>>>
>>> IMHO should document what happens when size-index is missing.
>>
>> I've tweaked the comment a bit.  I hesitate to go into a lot of
>> detail here and would expect people needing it to read the manual.
> 
> Right, but there should be just enough info for someone adding a new use
> of it to know what to do, without requiring the gcc docs.  The new
> comment is fine.
> 
>>> __buf[???]
>>
>> When size-index is missing at least one byte of the array must be
>> accessible (or the pointer must be null).  There's no way to specify
>> a constant size with the current syntax.  In the future I'd like to
>> try to teach GCC to get it from the argument itself (for ordinary
>> arrays as well as for VLAs):
> 
> Makes sense, just didn't know.
> 
>>> NOTE: does not use the __attr_access macro
>>
>> Fixed, thanks.
> 
> Ok.
> 

Thanks.  I have committed the latest patch in
06febd8c6705c816b2f32ee7aa1f4c0184b05248.

Martin