public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "pinskia at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/36296] wrong warning about potential uninitialized variable
Date: Wed, 28 May 2008 07:31:00 -0000	[thread overview]
Message-ID: <20080528073104.14554.qmail@sourceware.org> (raw)
In-Reply-To: <bug-36296-16207@http.gcc.gnu.org/bugzilla/>



------- Comment #6 from pinskia at gcc dot gnu dot org  2008-05-28 07:31 -------
(In reply to comment #5)
> BTW, the i = i trick

it only works in the initializer and not as a statement after the fact.

That is: 
#include <assert.h>
int foo (int x)
{
  int y = y;
  assert (x == 0 || x == 1);
  if (x == 0)
    y = 1;
  else if (x == 1)
    y = 2;
  return y;
}

Will work, also with the jump threading, GCC should be able to figure out that
y is always inlined (except when -DNDEBUG is used).

-- Pinski


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36296


  parent reply	other threads:[~2008-05-28  7:31 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-05-22  7:28 [Bug c/36296] New: " zimmerma+gcc at loria dot fr
2008-05-22  8:22 ` [Bug middle-end/36296] " pinskia at gcc dot gnu dot org
2008-05-22  8:34 ` vincent at vinc17 dot org
2008-05-22 10:21 ` rguenth at gcc dot gnu dot org
2008-05-22 11:02 ` vincent at vinc17 dot org
2008-05-22 11:23 ` vincent at vinc17 dot org
2008-05-28  7:31 ` pinskia at gcc dot gnu dot org [this message]
2008-05-28  8:19 ` vincent at vinc17 dot org
2008-08-18 17:25 ` manu at gcc dot gnu dot org
2008-08-18 22:59 ` vincent at vinc17 dot org
2008-08-18 23:39 ` [Bug middle-end/36296] bogus uninitialized warning (loop representation) manu at gcc dot gnu dot org
2008-08-19  1:33 ` vincent at vinc17 dot org
2008-08-19  2:34 ` [Bug middle-end/36296] bogus uninitialized warning (loop representation, VRP missed-optimization) manu at gcc dot gnu dot org
2008-12-25  3:03 ` pinskia at gcc dot gnu dot org
2009-02-02 23:44 ` av1474 at comtv dot ru
2009-02-03  0:28 ` manu at gcc dot gnu dot org

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20080528073104.14554.qmail@sourceware.org \
    --to=gcc-bugzilla@gcc.gnu.org \
    --cc=gcc-bugs@gcc.gnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).