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From: "muecker at gwdg dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/99797] accessing uninitialized automatic variables
Date: Tue, 30 Mar 2021 06:35:58 +0000	[thread overview]
Message-ID: <bug-99797-4-rpVp2zdql6@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-99797-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99797

--- Comment #6 from Martin Uecker <muecker at gwdg dot de> ---


Annex J is not normative. The normative text is the one I cited and that
mentions "address taken".  Reading an indeterminate values is not UB if it is
not a trap representation and then yield an unspecified value (at least
according to the normative text of the most recent ISO C standard). But the
standard is up to interpretation and may very well change. This is not my main
point.


My main point is that the behavior is dangerous because it breaks basic logical
assumptions about the code. So even if this were UB I think it is not ideal.

  parent reply	other threads:[~2021-03-30  6:35 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-27 13:47 [Bug c/99797] New: " muecker at gwdg dot de
2021-03-27 19:19 ` [Bug c/99797] " pinskia at gcc dot gnu.org
2021-03-27 19:19 ` pinskia at gcc dot gnu.org
2021-03-28  6:32 ` muecker at gwdg dot de
2021-03-28  7:08 ` pinskia at gcc dot gnu.org
2021-03-28  7:16 ` pinskia at gcc dot gnu.org
2021-03-30  6:35 ` muecker at gwdg dot de [this message]
2021-04-14 20:18 ` muecker at gwdg dot de
2021-04-18 18:09 ` [Bug middle-end/99797] " pinskia at gcc dot gnu.org
2021-04-19  5:43 ` muecker at gwdg dot de
2021-04-19 10:43 ` vanyacpp at gmail dot com
2021-04-19 18:57 ` muecker at gwdg dot de
2021-04-20 15:20 ` msebor at gcc dot gnu.org

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