[Bug libstdc++/39880] Specialisation is_error_code_enum<errc> should not exist

["chris_kohlhoff at internet-mail dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #3 from chris_kohlhoff at internet-mail dot org  2009-04-25 11:03 -------
It's the intended behaviour that the conversion constructor and assignment
operator be disabled. That is, the std::errc type should not be implicitly
convertible to error_code, only to error_condition.

If users want to create an error_code from a std::errc then they can use
make_error_code():

  error_code ec = make_error_code(errc::not_supported);

In a nutshell, ErrorConditionEnum concept means implicitly convertible to
error_condition but no implicit conversion to error_code. Likewise
ErrorCodeEnum means implicitly convertible to error_code but not to
error_condition.

(N.B. bugs 39881 and 39882 also have to be fixed to make this conversion work.)


-- 

chris_kohlhoff at internet-mail dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39880