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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/59615] "asm goto" output or at least clobbered operands
Date: Sat, 28 Dec 2013 16:28:00 -0000	[thread overview]
Message-ID: <bug-59615-4-i04buuQRSd@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-59615-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59615

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
But it would warn about it with -Wsign-compare.  You want unsigned r =
(unsigned) a + b; or similar to avoid undefined behavior if there is a
possibility of signed integer overflow.  Anyway, you definitely don't want to
use inline asm in this case, if there is some code GCC doesn't optimize as good
as you'd like to, just report that.


  parent reply	other threads:[~2013-12-28 16:28 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-12-28  0:23 [Bug c/59615] New: " hpa at zytor dot com
2013-12-28  8:42 ` [Bug c/59615] " jakub at gcc dot gnu.org
2013-12-28 10:29 ` ubizjak at gmail dot com
2013-12-28 16:28 ` jakub at gcc dot gnu.org [this message]
2013-12-30  1:37 ` hpa at zytor dot com
2013-12-30 17:53 ` glisse at gcc dot gnu.org
2013-12-30 17:56 ` jakub at gcc dot gnu.org
2013-12-30 18:17 ` glisse at gcc dot gnu.org
2021-09-01  1:05 ` [Bug inline-asm/59615] " pinskia at gcc dot gnu.org

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