From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Artem Khodush" <artem@duma.gov.ru>
To: nobody@gcc.gnu.org
Cc: gcc-prs@gcc.gnu.org
Subject: Re: c++/3171: Copy constructor does not accept parameter by value
Date: Wed, 13 Jun 2001 09:36:00 -0000
Message-id: <20010613163603.16533.qmail@sourceware.cygnus.com>
X-SW-Source: 2001-06/msg00567.html
List-Id: <gcc-prs.sourceware.org>

The following reply was made to PR c++/3171; it has been noted by GNATS.

From: "Artem Khodush" <artem@duma.gov.ru>
To: <gcc-gnats@gcc.gnu.org>
Cc:  
Subject: Re: c++/3171: Copy constructor does not accept parameter by value
Date: Wed, 13 Jun 2001 20:18:45 +0400

 Arun Saini , Gurgaon wrote: 
 > I am reproducing a portion of code and the error reported by the compiler
 > when I try to compile it.
 > 
 > 
 > Test someFunc(void)
 > {
 >   Test tempTest;
 >   tempTest.testVar = 10;
 > 
 >   return tempTest;
 > }
 > 
 > 
 > int main()
 > {
 >   Test t1;
 >   t1 = someFunc();
 >   return 0;
 > }
 > 
 
 This is not a bug. Here what's going on:
 the compiler created a temporary variable to store 
 the result of someFunc(), and you are trying to pass 
 that temporary to a copy constructor taking Test& 
 (without a const), which is not allowed in c++. 
 You have two options: either make Test::Test 
 copy constructor to take const Test& parameter, 
 or use the technique invented for std::auto_ptr
 to overcome this very problem (which is better 
 discussed elsewhere).