Date: Sat, 17 May 2003 16:20:05 -0400
From: David Witbrodt <dawitbro AT alpha DOT delta DOT edu>
Subject: References to temporary objects in C++
To: DJGPP mailing list <djgpp AT delorie DOT com>
Message-id: <3EC69975.55BE1034@alpha.delta.edu>
Organization: Delta College
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Reply-To: djgpp AT delorie DOT com

Hi folks,

This is maybe a little bit frivolous...

A year or two ago, I was frustrated with GCC not being able to accept
a reference to a temporary object as a function argument, like this:


class UserType
{	// ...
	// UserType  operator+  (const UserType&);
	// ...
};

void  func  (const UserType&);

int main ()
{	UserType a, b;
	func (a+b);
	// ...
}


I had learned C++ first in the early 1990s using Turbo C++, and I
remember using examples from Stroustrup's book that did things like
this without any trouble on that compiler.  

When this issue arose for me (a year or two ago) I found that the
DJGPP compiler didn't like this sort of syntax, that it was a known
problem, and that the advice being given on this list was to create
one's own temporary (i.e., Usertype c=a+b;) as a workaround.

I was tinkering around today, and tried again.  I notice that it is OK
now, no warnings or errors.

Was this a DJGPP issue?  Or simply a GCC issue?  Does anyone know when
it changed?  (This is obviously an unimportant matter, but I am simply
curious.)


Dave W.