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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/97976] Optimization relating to NULL pointer assumptions in gcc 9.1
Date: Thu, 26 Nov 2020 10:08:51 +0000	[thread overview]
Message-ID: <bug-97976-4-3t2yD8rAJ0@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-97976-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97976

--- Comment #11 from Jonathan Wakely <redi at gcc dot gnu.org> ---
The fact that objects cannot live at address zero is not just a GCC quirk. As I
said, it's required by the C and C++ standards. A null pointer cannot be
dereferenced, and cannot point to any object. I'm surprised that anybody finds
that surprising.

Embedded/kernel systems that violate that rule are the exception, not the norm.

  parent reply	other threads:[~2020-11-26 10:08 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-24 22:08 [Bug c++/97976] New: Optimization regression in 10.1 for lambda passed as template argument peter at int19h dot net
2020-11-24 22:14 ` [Bug c++/97976] " pinskia at gcc dot gnu.org
2020-11-24 22:24 ` peter at int19h dot net
2020-11-25  4:40 ` peter at int19h dot net
2020-11-25  8:25 ` [Bug c++/97976] Optimization relating to NULL pointer assumptions in gcc 9.1 rguenth at gcc dot gnu.org
2020-11-25 16:43 ` peter at int19h dot net
2020-11-25 18:18 ` redi at gcc dot gnu.org
2020-11-25 19:46 ` peter at int19h dot net
2020-11-25 23:55 ` redi at gcc dot gnu.org
2020-11-26  0:20 ` redi at gcc dot gnu.org
2020-11-26  1:37 ` peter at int19h dot net
2020-11-26 10:08 ` redi at gcc dot gnu.org [this message]
2020-11-26 10:09 ` redi at gcc dot gnu.org

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