(I sent this earlier to Paul but forgot to CC the list...) I believe the problem here is that "test dd = foo()" is using a temporary object (returned by foo). You cannot pass a non-const reference to that temporary object into test's copy constructor. Temporary objects are always "const". You can, of course, pass a const reference to a temporary object. Similarly, if foo() returns a reference, that reference must point to a valid (not temporary) object, so passing a reference to THAT object into test's copy constructor is just fine. So I think gcc's behavior is correct (though the error text is a bit unclear). I don't know what Microsoft's compiler is doing in that case, but it seems unusual and could probably lead to bad behavior. --- Tony Wetmore Raytheon Solipsys mailto:tony.wetmore@xxxxxxxxxxxx http://www.solipsys.com -----Original Message----- From: gcc-help-owner@xxxxxxxxxxx [mailto:gcc-help-owner@xxxxxxxxxxx] On Behalf Of Eljay Love-Jensen Sent: Wednesday, May 12, 2004 12:05 PM To: paul moore; gcc-help@xxxxxxxxxxx Subject: Re: Copy constructor with non const rhs arg Hi Paul, I believe a copy constructor requires a const parameter. But I may be mistaken. I've been mistaken before. You can make the auto_ptr member variable mutable. --Eljay
