r176924 - Tighten up the rules for precise lifetime and document

[John McCall]

On Mar 13, 2013, at 7:28 AM, Dmitri Gribenko <gribozavr at gmail.com> wrote:
> On Wed, Mar 13, 2013 at 11:20 AM, Jean-Daniel Dupas
> <devlists at shadowlab.org> wrote:
>> 
>> Le 13 mars 2013 à 04:10, John McCall <rjmccall at apple.com> a écrit :
>> 
>>> Author: rjmccall
>>> Date: Tue Mar 12 22:10:54 2013
>>> New Revision: 176924
>>> 
>>> URL: http://llvm.org/viewvc/llvm-project?rev=176924&view=rev
>>> Log:
>>> Tighten up the rules for precise lifetime and document
>>> the requirements on the ARC optimizer.
>>> 
>>> rdar://13407451
>>> 
>> 
>> …
>> 
>>> +
>>> +  Specifically, ARC is sometimes permitted to optimize ``release``
>>> +  operations in ways which might cause an object to be deallocated
>>> +  before it would otherwise be.  Without this, it would be almost
>>> +  impossible to eliminate any ``retain``/``release`` pairs.  For
>>> +  example, consider the following code:
>>> +
>>> +  .. code-block:: objc
>>> +    id x = _ivar;
>>> +    [x foo];
>>> +
>> 
>> For some reason, this code block does not appears in the generated html at "http://clang.llvm.org/docs/AutomaticReferenceCounting.html"
>> I'm not familiar with the rst format though, so I can tell you what is wrong here.
> 
> Fixed in r176948.

Thanks!

John.