c++/8279: REGRESSION: failure to find a matching function in

[Wolfgang Bangerth]

> Even if gcc's behavior is correct, the diagnostic is puzzling:
>
> PREFIX/include/c++/3.2.1/bits/stream_iterator.h:141: no 
>    match for `std::basic_ostream<char, std::char_traits<char> >& << const 
>    std::pair<std::string, unsigned int>&' operator
>
> when there is what appears to be an exact match.  Strategies to come up
> with a better diagnostic (e.g. tell the user why the function s/he
> intended to use isn't accepted) would be wlcome.

Maybe a first simple step would be to change the message to say
      no match for `...' found during name lookup
Indicating that there _might_ even be such a name, but that it just was 
not found. This would at least give a clue as to what may be going wrong.

Regards
  Wolfgang

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Wolfgang Bangerth              email:           bangerth@ticam.utexas.edu
                               www: http://www.ticam.utexas.edu/~bangerth