>Submitter-Id:  net
>Originator:    Jaakko Niemi <[EMAIL PROTECTED]>
>Organization:  The Debian project
>Confidential:  no
>Synopsis:      g++-3.0 copies constructors
>Severity:       serious
>Priority:       medium
>Category:      c++
>Class:         sw-bug
>Release:       3.0 (Debian GNU/Linux)
>Environment:
System: Debian GNU/Linux (testing/unstable)
Architecture: i686
        
host: i386-linux
build: i386-linux
target: i386-linux
configured with: ../src/configure -v 
--enable-languages=c,c++,java,f77,proto,objc --prefix=/usr 
--infodir=/share/info --mandir=/share/man --enable-shared --with-gnu-as 
--with-gnu-ld --with-system-zlib --enable-long-long --enable-nls 
--without-included-gettext --disable-checking --enable-threads=posix 
--enable-java-gc=boehm --with-cpp-install-dir=bin --enable-objc-gc i386-linux
>Description:
[ Reported to the Debian BTS as report #103980.
  Please CC [EMAIL PROTECTED] on replies.
  Log of report can be found at http://bugs.debian.org/103980
  sfs report: http://www.mit.edu:8008/snafu.fooworld.org/sfs/116
]
        

SFS (secure file system) 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

  a << 10;
}
-----


>How-To-Repeat:
        
>Fix:
        


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