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From: "virkony at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/59813] tail-call elimintation didn't fired with left-shift of char to cout
Date: Wed, 15 Jan 2014 07:18:00 -0000	[thread overview]
Message-ID: <bug-59813-4-CO7DiXWKXe@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-59813-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59813

--- Comment #4 from Nikolay Orliuk <virkony at gmail dot com> ---
Andrew Pinski, as long as address of variable isn't taken out of scope of
function that is being tail-call optimized there is no need to worry about it
and it is safe to optimize. Am I wrong?

If stdc++ lib contains code like:

ostream &operator<<(ostream &os, char x)
{ os.__escape = &x; }

That's probably wrong and should be fixed.

Tried to override with:

ostream &operator<<(ostream &os, char x)
{ cout.put(x); return os; } // works on all 4.5.4, 4.7.3 and 4.8.2

ostream &operator<<(ostream &os, char x)
{ cout.write(&x, 1); return os; } // fails even without "bar" for 4.7.3 and
4.8.2

Note that strange behaviour of 4.7.3. Is that means that adding "bar" fires
inlining?..


  parent reply	other threads:[~2014-01-15  7:18 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-01-14 21:35 [Bug c++/59813] New: " virkony at gmail dot com
2014-01-14 22:05 ` [Bug c++/59813] " virkony at gmail dot com
2014-01-15  0:13 ` pinskia at gcc dot gnu.org
2014-01-15  7:18 ` virkony at gmail dot com [this message]
2014-01-15  7:23 ` jakub at gcc dot gnu.org

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