[PATCH] Fix libstdc++/6503

[Gabriel Dos Reis]

Paolo Carlini <pcarlini@unitus.it> writes:

| Gabriel Dos Reis wrote:
| 
| >Well, my remark was based on your description:
| >
| >   I have fixed this PR according to Scott Meyers' guideline about 
| >   comparison operators as non-member functions (Effective STL, 119): now 
| >   all the _Deque_iterator comparison operators are non-members
| >
| >and the removal of member comparaison operators.  So I wanted to know
| >whether that isn't an ABI change.
| >
| I see.
| 
| Therefore, just to be completely clear, now that I have added that 
| missing information (sorry) about the non-existence of instantiations of 
| deque in the libstdc++.so binary, do you agree that there is no risk of 
| ABI mismatches both ways?

I would say there is no risk, but I would like people much more
knowledgeable than I double check.  That is why I asked the question.

-- Gaby