[patch] PR libstdc++/9561, take 2

[Benjamin Kosnik]

>
>2003-03-08  Jerry Quinn  <jlquinn@optonline.net>
>
>	PR libstdc++/9561
>	* include/bits/basic_ios.h (_M_setstate): New.
>	* include/bits/ostream.tcc (operator<<): Use it.
>	* include/bits/istream.tcc (operator>>): Use it.
>	* include/std/std_ostream.h (operator<<): Make friends.
>	* include/std/std_istream.h (operator>>): Make friends.
>	* testsuite/27_io/ostream_exception.cc,
>	testsuite/27_io/istream_exception.cc: New tests.

Jerry, this looks great, thanks. Please check it in. 

FYI I appended Mark Mitchell's answer to the template question below.

best,
benjamin


> in the patch below, are the things within the #if 1 / #endif really
> necessary? I would think that the friend declaration above it would also
> include the specialization right below it, within the #if/#endif block

Yes, they are.

Remember that there is no such thing as a partial specialization of a 
function template; there is only overloading.

Here is a small example.  There are two overloaded templates named f; the 
friend declaration refers to the first, but not the second, which causes 
the instatiation at the end to fail.

template <typename T>
void f (T);

template <typename T>
void f (T*);

class C {
  template <typename T>
  friend void f (T);

  int i;
};

template <typename T>
void f (T*) {
  C c;
  c.i = 3;
}

template void f (int*);