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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/50056] Binding a temporary object to a reference
Date: Fri, 12 Aug 2011 13:27:00 -0000	[thread overview]
Message-ID: <bug-50056-4-vJ6WtSHhfe@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-50056-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50056

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-08-12 12:46:42 UTC ---
Are you sure G++ isn't correct?
The cast creates a temporary reference, which binds to the temporary object,
then initalizes 's' with the temporary reference. That means the temporary
object's lifetime is extended to the same lifetime as the reference, but the
reference is temporary so is destroyed at the end of the full expression.

call S::S()
bind to temporary reference
initialize s from temporary reference
temporary reference goes out of scope
call S::~S()
call S::func()
s goes out of scope

if you do this:

const S& s = S();

then you get the behaviour I assume you are expecting:

call S::S()
initialize s temporary object
call S::func()
s goes out of scope
call S::~S()


  reply	other threads:[~2011-08-12 12:47 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-08-12 12:39 [Bug c++/50056] New: " wolfgang.roehrl@gi-de.com
2011-08-12 13:27 ` redi at gcc dot gnu.org [this message]
2011-08-12 15:07 ` [Bug c++/50056] " wolfgang.roehrl@gi-de.com
2011-08-16 23:55 ` jason at gcc dot gnu.org

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