Bug#103980: g++-3.0: copies constructors

[Jaakko Niemi <liiwi@lonesom.pp.fi>]

Package: g++-3.0
Version: N/A
Severity: normal

 SFS fails to compile with gcc 3.0, and it was tracked down to this 
example code that reproduces the error:

-------------
class aios {
  friend class aiosout;

public:
  aios ();
  ~aios ();
};

class aiosout {
  aiosout (const aiosout &o);
  aiosout &operator= (const aiosout &);
public:
  aiosout (aios &a) {}
  ~aiosout () {}
};

template<class T> inline const aiosout&
operator<< (const aiosout &o, const T &a)
{
  return o;
}

void fault(void)
{
  aios a;

  // normally a C++ compiler should resolve the following like this:
  //  tmp = aiosout(a)
  //  operator<< (tmp, 10);
  // apparently, g++ 3.0 tries to do something like this:
  //  tmp1 = aiosout(a)
  //  tmp2 = aiosout(tmp1)   <== copy constructor (unusable!)
  //  operator<< (tmp2, 10);
  // which is wasteful even when it works... maybe now we know why
  // g++ is known to take so much longer to compile stuff...

  a << 10;
}
-------------

 If you try to reproduce this with SFS sources, please use the cvs
version, as it has other gcc 3 related fixes already in. You can find
the cvs instructions from http://www.fs.net.

 If there is any other information that I can provide, please let me know.

	Thanks.

-- System Information
Debian Release: testing/unstable
Kernel Version: Linux jumper 2.4.6 #1 Wed Jul 4 15:33:15 EEST 2001 i686 unknown