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From: "manu at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/37591] suppress "signed and unsigned" warnings when signed value known to be positive
Date: Mon, 22 Sep 2008 13:29:00 -0000	[thread overview]
Message-ID: <20080922132820.1791.qmail@sourceware.org> (raw)
In-Reply-To: <bug-37591-37@http.gcc.gnu.org/bugzilla/>



------- Comment #4 from manu at gcc dot gnu dot org  2008-09-22 13:28 -------
I don't understand why this is not closed as wontfix. These warnings are coming
from the front-end. 

Unless we do one of the following:

a) some CCP and VRP in the FE, or
b) move the warnings to the middle-end,

this cannot be fixed. And the consensus seems to be that we do not want to do
either of them. And from the many problems we see with Wuninitialized, we
already know that moving the warnings to the middle-end causes a lot of
problems. Also, VRP is only enabled at -O2. And it does not work with sets,
only ranges, so the following will still not work:

adj = (flag) ? 0 : 2;
return MIN(adj, limit);

(I am sure that we have already, probably closed, a PR about this).


-- 

manu at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |manu at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37591


  parent reply	other threads:[~2008-09-22 13:29 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-09-19 18:13 [Bug c/37591] New: " zackw at panix dot com
2008-09-19 20:56 ` [Bug c/37591] " pinskia at gcc dot gnu dot org
2008-09-19 21:29 ` zackw at panix dot com
2008-09-20  9:11 ` rguenth at gcc dot gnu dot org
2008-09-22 13:29 ` manu at gcc dot gnu dot org [this message]
2008-09-22 15:47 ` zackw at panix dot com
2008-09-22 16:44 ` manu at gcc dot gnu dot org
     [not found] <bug-37591-4@http.gcc.gnu.org/bugzilla/>
2015-07-06  8:59 ` daniel.marjamaki at gmail dot com
2015-07-06 12:31 ` manu at gcc dot gnu.org

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