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From: "joseph at codesourcery dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug sanitizer/55309] gcc's address-sanitizer 66% slower than clang's Date: Fri, 22 Feb 2013 16:11:00 -0000 [thread overview] Message-ID: <bug-55309-4-9ed0cEFhFv@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-55309-4@http.gcc.gnu.org/bugzilla/> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55309 --- Comment #55 from joseph at codesourcery dot com <joseph at codesourcery dot com> 2013-02-22 16:10:49 UTC --- I believe the arguments to memcmp must point to objects with at least the given number of bytes. (For strcmp, they must point to NUL-terminated strings. For strncmp, they must point to objects that either have at least the given number of bytes or have bytes present up to a NUL within that number of bytes - there's no guarantee that comparison stops early when characters differ except for not reading after a NUL. By comparison, the array passed to memchr may be shorter than the given length if a matching character is found early - see the wording added in C11 for memchr for alignment with POSIX. But memcmp has no such special rule.)
next prev parent reply other threads:[~2013-02-22 16:11 UTC|newest] Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top 2012-11-13 10:01 [Bug other/55309] New: " markus at trippelsdorf dot de 2012-11-13 21:10 ` [Bug other/55309] " konstantin.s.serebryany at gmail dot com 2012-11-13 21:31 ` markus at trippelsdorf dot de 2012-11-14 7:52 ` jakub at gcc dot gnu.org 2012-11-14 16:38 ` jakub at gcc dot gnu.org 2012-11-14 17:03 ` markus at trippelsdorf dot de 2013-02-05 9:22 ` [Bug sanitizer/55309] " kcc at gcc dot gnu.org 2013-02-05 9:43 ` kcc at gcc dot gnu.org 2013-02-05 9:56 ` jakub at gcc dot gnu.org 2013-02-05 10:31 ` kcc at gcc dot gnu.org 2013-02-05 10:42 ` kcc at gcc dot gnu.org 2013-02-05 10:55 ` jakub at gcc dot gnu.org 2013-02-05 11:18 ` markus at trippelsdorf dot de 2013-02-05 11:24 ` jakub at gcc dot gnu.org 2013-02-05 11:26 ` jakub at gcc dot gnu.org 2013-02-05 12:23 ` kcc at gcc dot gnu.org 2013-02-06 10:56 ` dodji at gcc dot gnu.org 2013-02-06 11:19 ` kcc at gcc dot gnu.org 2013-02-06 12:25 ` kcc at gcc dot gnu.org 2013-02-06 12:39 ` rguenth at gcc dot gnu.org 2013-02-06 12:43 ` kcc at gcc dot gnu.org 2013-02-06 12:49 ` jakub at gcc dot gnu.org 2013-02-06 15:03 ` dodji at gcc dot gnu.org 2013-02-07 5:02 ` kcc at gcc dot gnu.org 2013-02-07 17:01 ` jakub at gcc dot gnu.org 2013-02-07 17:18 ` dvyukov at google dot com 2013-02-08 6:31 ` kcc at gcc dot gnu.org 2013-02-08 9:02 ` jakub at gcc dot gnu.org 2013-02-08 9:13 ` kcc at gcc dot gnu.org 2013-02-08 9:25 ` jakub at gcc dot gnu.org 2013-02-11 14:43 ` kcc at gcc dot gnu.org 2013-02-11 15:03 ` jakub at gcc dot gnu.org 2013-02-12 6:48 ` kcc at gcc dot gnu.org 2013-02-12 7:03 ` kcc at gcc dot gnu.org 2013-02-12 8:40 ` jakub at gcc dot gnu.org 2013-02-12 8:47 ` dvyukov at google dot com 2013-02-12 8:59 ` kcc at gcc dot gnu.org 2013-02-12 11:18 ` kcc at gcc dot gnu.org 2013-02-12 11:31 ` kcc at gcc dot gnu.org 2013-02-12 11:42 ` jakub at gcc dot gnu.org 2013-02-12 14:00 ` howarth at nitro dot med.uc.edu 2013-02-12 14:12 ` jakub at gcc dot gnu.org 2013-02-12 14:42 ` howarth at nitro dot med.uc.edu 2013-02-22 7:11 ` kcc at gcc dot gnu.org 2013-02-22 8:31 ` Joost.VandeVondele at mat dot ethz.ch 2013-02-22 8:36 ` kcc at gcc dot gnu.org 2013-02-22 13:09 ` jakub at gcc dot gnu.org 2013-02-22 13:52 ` kcc at gcc dot gnu.org 2013-02-22 13:55 ` Joost.VandeVondele at mat dot ethz.ch 2013-02-22 14:30 ` kcc at gcc dot gnu.org 2013-02-22 14:54 ` kcc at gcc dot gnu.org 2013-02-22 15:01 ` jakub at gcc dot gnu.org 2013-02-22 15:04 ` jakub at gcc dot gnu.org 2013-02-22 15:06 ` kcc at gcc dot gnu.org 2013-02-22 15:14 ` jakub at gcc dot gnu.org 2013-02-22 16:11 ` joseph at codesourcery dot com [this message] 2013-02-26 7:43 ` kcc at gcc dot gnu.org 2013-02-28 11:32 ` kcc at gcc dot gnu.org 2014-01-27 8:22 ` trippels at gcc dot gnu.org
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