From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ryszard Kabatek <rysio@rumcajs.chemie.uni-halle.de>
To: egcs@egcs.cygnus.com
Subject: Strange warnings
Date: Mon, 31 May 1999 21:36:00 -0000
Message-ID: <Pine.LNX.3.96.990505100034.8687A-100000@rumcajs.chemie.uni-halle.de>
X-SW-Source: 1999-05n/msg00103.html
Message-ID: <19990531213600.OwqieMK3SOPAVzjLltqia7JJR2cP6F8g83sY6vBMPBg@z>

In the sample below the class X should have a standard constructor
generated by the compiler. But I get the following warnings:

# eg++ x.cc
x.cc:6: warning: `class X' only defines private constructors and has no
friends
x.cc: In function `static class X * X::create()':
x.cc:5: no matching function for call to `X::X ()'
x.cc:3: candidates are: X::X(const X &)


The first warning I get too if I define a private standard constructor.
But there is a static function, that creates new instances of X,
class X does not need friend functions or classes.


# cat x.cc

class X {
    X(const X&);
  public:
    static X* create() {return new X();}
};

int main(int argc, char* argv)
{
  X* p = X::create();
  delete p;
}


Ryszard Kabatek
Martin-Luther University Halle-Wittenberg, Department of Physical Chemistry
Geusaer Str. 88, 06217 Merseburg, Germany
Tel. +49 3461 46 2487 Fax. +49 3461 46 2129