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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/47980] Inefficient code for local const char arrays
Date: Thu, 03 Mar 2011 22:00:00 -0000	[thread overview]
Message-ID: <bug-47980-4-pFHsxVRTUf@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-47980-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47980

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|REOPENED                    |RESOLVED
          Component|c                           |middle-end
         Resolution|                            |INVALID

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> 2011-03-03 22:00:36 UTC ---
Actually the copying is correct.
Take:
void f(const char *p);

void g(int t) {
  const char foo[] = "aoeuaoeuaeouaeouaoeuaoeaoxbxod";
  f(foo, t);
  if (!t)
    g(1);
}

const char *a;

void f(const char *p, int t)
{
  if (!t)
    a = p;
  else if (a == p)
    abort ();
}

void main(void)
{
  g(0);
}

This program should not abort with your "optimization", it will.


  parent reply	other threads:[~2011-03-03 22:00 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-03-03 21:40 [Bug c/47980] New: " rafael.espindola at gmail dot com
2011-03-03 21:47 ` [Bug c/47980] " ktietz at gcc dot gnu.org
2011-03-03 21:50 ` rafael.espindola at gmail dot com
2011-03-03 21:52 ` ktietz at gcc dot gnu.org
2011-03-03 22:00 ` pinskia at gcc dot gnu.org [this message]
2011-03-03 22:00 ` jakub at gcc dot gnu.org
2011-03-04 16:26   ` Jan Hubicka
2011-03-03 23:07 ` [Bug middle-end/47980] " pinskia at gcc dot gnu.org
2011-03-04 16:26 ` hubicka at ucw dot cz

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