When a function has
a parameter type extended-floating-point-type,
the implementation provides overloads
for all cv-unqualified extended floating-point types ([basic.fundamental]).
The class template
basic_ostream
defines a number of member function
signatures that assist in formatting and writing output to output sequences
controlled by a stream buffer.
They may use other public members of
basic_ostream
except that they shall not invoke any virtual members of
rdbuf()
except
overflow(),
xsputn(),
and
sync().
If one of these called functions throws an exception, then unless explicitly noted otherwise
the output function sets
badbit
in the error state.
If
badbit
is set in
exceptions(),
the output function
rethrows the exception without completing its actions, otherwise
it does not throw anything and proceeds as if the called function had returned
a failure indication.