http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53683
--- Comment #2 from Rui Maciel <rui.maciel at gmail dot com> 2012-06-15 13:08:01 UTC --- (In reply to comment #1) > (In reply to comment #0) > > If, in the test program, std::u16string is replaced with std::u32string, the > > program is successfully compiled. > > That's surprising - it shouldn't work (and doesn't with G++ 4.7) > > > It would be nice if std::cout also supported std::u16string objects. > > std::cout is for char > > You could use std::wstring_convert to convert a std::u16string to std::string > for output (but GCC doesn't have wsring_convert yet, I plan to work on it next > week.) You are absolutely right. I assumed that the definition of std::ostream also included definitions for operator<< that supported definitions of basic_string<charT> with a charT other than char, but it appears my assumptions were completely baseless. In that case, is it possible to tweak gcc to return a friendlier error message? The current one is a bit long and frightening. For example, is it possible define an operator<< that throws a compiler error with any message similar to "basic_ostream<charT,traits> doesn't provide an operator<< for basic_string<some_other_T>"? This sort of error message would be a whole lot easier to digest.
