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Re: debug algorithms


I didn't expect that in addition to guaranty binary compatibility of libstdc++ itself we also have to guaranty binary compatibility of different components built with different versions of libstdc++, especially in debug mode ! What I meant with 100% compatibility was that I do not expect abi or any other test to fail after this patch.

I also noticed that you added on the 31 of august a cached index in the hashtable implementation. This is going to introduce exactly the same kind of breaking change, isn't it ? IMO libraries already using this implementation and exposing it are much more common than libraries exposing debug mode structures.

I will start to consider forward_list.

François


On 09/06/2010 10:31 PM, Paolo Carlini wrote:
On 09/06/2010 09:44 PM, François Dumont wrote:
IMHO, even if this patch has a lot of impact on the code, it is 100%
compatible with existing user code
If you are changing _Safe_iterator, like this:

-  template<typename _Iterator, typename _Sequence>
+  template<typename _Sequence, bool _IsConst>
      class _Safe_iterator;

then certainly it is not: two different objects, one built with the old
headers and one with the new headers and passing around an iterator
cannot be linked together. I warn you these headers are tricky, we
really want to be 100% sure we are not breaking anything for 4.6.0, in
the various modes and without penalizing performance (eg, make sure the
fill and copy for deque::iterator are still used in normal mode, etc).

If you want my advice, let's first make sure we have a working debug
mode for forward_list in 4.6.0, and let's give the algorithms *more*
thought.

Paolo.




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